YSM Issue 86.3

Yale Scientific

Established in 1894

THE NATION’S OLDEST COLLEGE SCIENCE PUBLICATION

April 2013 Vol. 86 No. 3

AILMENTS OF A GRAYING POPULATION

How public health is shifting to accomodate the elderly

PAGES 14-17

NEUROSCIENCE

Decoding

Depression

Acetylcholine receptors

unlock clues to the

biochemical basis of

depression

GENOMICS

African Sleeping

Sickness

“Serendipitous”

discovery leads to

replication of viral

infection process

NANOTECHNOLOGY

Hybrid Energy

Harvesters

Nanoscale hybrid

cells harness energy

from surrounding

light and motion

PAGE 8 PAGES 12-13

PAGES 32-33

everyday Q&A

Q&A

If a 300 million year trend continues, the Y chromosome may find itself on the path to extinction.

The male sex chromosome and

its X counterpart were initially

identical, but over the course of

millennia, the Y has lost hundreds

of genes. Some suggest that if this

pattern persists, the Y chromosome

may completely disappear

from the genomic map in five to

ten million years.

Recent research, however, has

suggested otherwise. A study

by Dr. Jennifer Hughes at the

Whitehead Institute compared

the Y chromosome sequence of

the chimpanzee, which differs

from humans by six million years

of evolution, to that of the rhesus monkey, which differs by 25

million years. Surprisingly, the Y chromosome has undergone no

changes over the past six million years, and it has lost only one

gene in 25 million years. In other words, it looks like gene loss has

Q&A

Does the Y Chromosome “Rot”?

BY CARRIE CAO

Originally one of a pair of identical autosomes, the Y

chromosome has since lost a large chunk of its genes.

IMAGE COURTESY OF SCRIPPS COLLEGE

What Causes Iridescence?

reached an asymptote.

Gene sequencing has also provided

an additional insight: While

the Y chromosome’s genetic content

has not changed in the past 25

million years, it has lost large sections

of repeated DNA sequences.

Proponents of the Y chromosome

decay theory suggest that the

remaining sequences will eventually

be erased as well, but others believe

natural selection has preserved the

genes for a reason, and that decay

represents a kind of “purifying”

force that will weed out all but the

most essential genes.

Whether or not the Y will eventually disappear remains a controversial

question, but scientists do agree on one thing: We do not

know enough about the function of its genes to make a definite

prediction yet. For now, it seems like Y chromosome is here to stay.

Iridescence is seen throughout nature in feathers, scales, and other objects, but how does it work?

BY RENUSHA INDRALINGAM

If you have ever caught a glimpse of a shimmering peacock

feather, a butterfly wing, or even a soap bubble, you may have

noticed that the object seems to change color as you shift your

perspective — in fact, iridescence has played an inventive optical

trick on you. What exactly creates this mesmerizing effect?

Light travels in predictable patterns of waves, with rising crests

and falling troughs. Many colors found in nature are produced

by pigmentation, which characterizes the absorption of certain

wavelengths of light and the reflection of others. Iridescence,

however, occurs when an object’s physical structure causes light

waves to combine with one another, a phenomenon known as

interference. In constructive interference, light waves combine

so that the crests and troughs line up to reinforce each other,

increasing the vibrancy of the reflected color. Destructive interference

occurs when the crests and troughs cancel each other out

to dim the color. Thus, as the observer’s viewing angle shifts, the

colors of the iridescent object change depending on the varying

degrees of constructive and destructive interference.

A variety of structural features interact with light to create

iridescence. Some iridescent objects have multiple layers, such as

a butterfly wing composed of layers of identically shaped scales.

Light reflected from the top layer collides with light reflected

from the bottom layers to cause interference.

While alluring, iridescence is more than just an optical curiosity.

IMAGE COURTESY OF SANTOSH SHANMUGA

As viewers change their point of view in relation to the

scarlet macaw’s iridescent feathers, the colors of the

feathers appear to change as well.

In nature, it is used to recognize organisms of the same species,

choose mates, and confuse and evade predators, proving it to be

an extremely useful adaptation in the animal kingdom.

2 Yale Scientific Magazine | April 2013 www.yalescientific.org

NEWS

5 Letter from the Editor

6 Novel Nano Biosensors Developed

contents

November 2013 / Vol. 86 / Issue No. 4

ON THE COVER

6

7

Joan Steitz Receives the Grande Médaille

Q&A with Physics Professor Reina

Maruyama

7

8

9

10

11

Q&A with Physics Professor Michel

Devoret

Uncovering the Process of Starbirth

New Neural Imaging Methods Developed

Small Molecule Designed to Fight Heart

Ischemia

54-Year-Old Mathematics Conjecture

Finally Proven

FEATURES

27

28

30

32

33

34

35

36

37

38

Current Events

The Impact of Sequestration on Research

Oceanography

An Undiscovered World of Ocean

Viruses

Geology

Mega-Canyon Uncovered in Greenland

Environment

Mythbusters: The Great Pacific Garbage

Patch

Neuroscience

Debunking Science: Near-Death

Experiences

Undergraduate Profile

Jan Kolmas, TC '14

Alumni Profile

Yen-Yen Chang, SY '94, F&ES '01

Ecology

Urbanization Boosts Animal Brain Size

Trivia

Five Things You Didn't Know about

Black Holes

Book Reviews

-Brilliant Blunders

-The Eternal Darkness

-Packing for Mars

8

12

The Future of

Space Exploration

The great unknown

beckons as modern

technology and the

space industry’s rise to

prominence offer a new

paradigm in exploration.

From asteroid mining to

X PRIZE, rockets are just

the beginning.

15

18

Astronomers Examine the Process of Starbirth

Yale Professor Héctor Arce and an international collaboration of

astronomers have used the Atacama Large Millimeter/submillimeter

Array (ALMA) to obtain striking images of a protostar, providing a new

glimpse into the dynamics of star formation.

HIV & TB:

Understanding

the Epidemic

Why is the TB/HIV dual

epidemic so pervasive in

Sub-Saharan Africa? Dr.

Richard Bucala's research

at the Yale School of

Medicine suggests that

genetics holds the answer.

Targeting

Diabetes at

its Source

A clinical trial led by Yale

professor Kevan Herold

may lead to an effective

new treatment for type 1

diabetes.

20

Glia

25

IMAGE COURTESY OF ALMA/ESO

IMAGE COURTESY OF COLON-RAMOS

& Growth: Synapses in the

Developing Brain

IMAGES COURTESY Of BARAN SARAC

Optimizing Microstructures to

Enhance Durability

More articles available online at www.yalescientific.org

www.yalescientific.org

November 2013 | Yale Scientific Magazine 3

86.3

the human population

EXPLOSION

“

”

You cannot control

your own population

by force, but it

can be distracted

by consumption.

Noam Chomsky

How is age becoming a

burden on the population?

Along with population expansion, the world has seen

a rise in life expectancy, bringing with it a whole

host of age-related struggles.

Read more: p. 14

How has population growth

engendered disease?

As cities become more crowded, control of the

spread of diseases like HIV/AIDS has become a

pressing issue.

Read more: p. 26

Recent research on African Sleeping Sickness

has yielded clues to halting its deadly spread in

Sub-Saharan Africa.

Read more: p. 12

What is the history of

the human race?

The population has surpassed seven billion.

This explosive growth has had an enormous

impact on the planet and its inhabitants.

Read more: p. 23

How can we preserve

biodiversity?

As the population expands, so does its borders.

New methods are being developed to

combat these ecological consequences.

Read more: p. 20


NEUROSCIENCE

Acetylcholine receptors

unlock clues to the

biochemical basis of

depression

THE NATION’S OLDEST COLLEGE SCIENCE PUBLICATION

April 2013 Vol. 86 No. 3

GENOMICS

“Serendipitous”

discovery leads to

replication of viral

infection process

NANOTECHNOLOGY

Nanoscale hybrid

cells harness energy

from surrounding

light and motion

PAGE 8 PAGES 12-13

PAGES 32-33

April 2013 Volume 86 No. 3

Editor-in-Chief

Publishers

Managing Editors

Articles Editors

News Editor

Features Editor

Copy Editors

Online Editors

Production Manager

Layout Editors

Arts Editor

Webmaster

Multimedia Editor

Advertising Manager

Distribution Manager

Subscriptions Manager

Outreach Chair

Special Events Coordinator

Staff

William Zhang

Qiaonan Zhong

Elizabeth Himwich

William Gearty

Spencer Katz

Contributing Writers

Sophie Janaskie

Cristal Suarez

Andrew Deveau

Smita Shukla

Mahbuba Tusty

Yale Scientific

M A G A Z I N E

Established 1894

Jessica Hahne

Karthikeyan Ardhanareeswaran

Stella Cao

Li Boynton

Renee Wu

Terin Patel-Wilson

John Urwin

Alyssa Picard

Rebecca Su

Grace Cao

Dennis Wang

Walter Hsiang

Jason Young

Jessica Schmerler

Carrie Cao

Christina de Fontnouvelle

Chanthia Ma

Jeremy Liu

Seung Yeon Rhee

Aurora Xu

Alex Co

Deeksha Deep

Naaman Mehta

Savina Kim

Kevin Boehm

Jiahe Gu

Tierney Larson

Blake Smith

Margaretta Midura

Jared Milfred

Yigit Yorulmaz

Zoe Kitchel

Brendan Shi

Renusha Indralingam

Advisory Board

Sean Barrett, Chair

Physics

Priyamvada Natarajan

Astronomy

Kurt Zilm

Chemistry

Fred Volkmar

Child Study Center

Stanley Eisenstat

Computer Science

James Duncan

Diagnostic Radiology

Melinda Smith

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Electrical Engineering

Werner Wolf

Emeritus

John Wettlaufer

Geology & Geophysics

William Summers History of Science & History of Medicine

Jeremiah Quinlan

Undergraduate Admissions

Carl Seefried Yale Science & Engineering Association

The Yale Scientific Magazine (YSM) is published four times a year by

Yale Scientific Publications, Inc. Third class postage paid in New

Haven, CT 06520. Non-profit postage permit number 01106 paid

for May 19, 1927 under the act of August 1912. ISN:0091-287.

We reserve the right to edit any submissions, solicited or unsolicited,

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students, and Yale University is not responsible for its contents.

Perspectives expressed by authors do not necessarily reflect the

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Please send questions and comments to ysm@yale.edu.

F R O M T H E E D I T O R

The Human Population Explosion

Population is measured by statistics, marked by numbers. Demographics can be plotted

on number-based pyramids; births and deaths can be charted on line graphs. The U.S.

Census Bureau website provides an up-to-date estimate of the number of people in the

world at the click of a button. We have no trouble regulating records of populations, but

do we have any means of controlling population growth itself?

Since the Industrial Revolution began in the West during the late 1700s, advancements

in technology, sanitation, and public health have continually lowered death rates around

the world, causing population growth rates to skyrocket. This sudden, exponential

growth of the world population is often described as an “explosion” — a term that,

at first glance, connotes anything but control. In many cases, explosions are associated

with violence, feelings of danger, the atrocities caused by nuclear bombs and terrorism.

However, in other contexts, we have learned to regulate explosions, directing when they

should happen and when they should stop: chemistry lab experiments, fourth-of-July

fireworks, cartoon characters who comically mishandle dynamite and spring back to life.

The occasions and implications of explosions, as well as our level of control concerning

them, vary greatly. But all explosions have in common the same general process: starting

suddenly, spreading quickly, permeating their surroundings, and effecting change.

Welcome to Issue 86.3 of the Yale Scientific. This issue will explore “The Human

Population Explosion,” from a wide range of perspectives, highlighting advancements

in technology and medical care, various human population phenomena, and the larger

picture of how human population dynamics fit into ecosystems and compare to other

species. Our goal for this issue is to provide an accurately complex picture of population.

The problem is that population does not stop to pose for pictures; it is constantly

moving and growing and changing. By the time this issue is released, there will be new

data available on populations around the world. There will be newer, more up-to-date

statistics, pyramids, and line graphs. The button on the U.S. Census Bureau website will

refresh to a webpage that estimates a new, much higher number than it did when the

pages of this issue left the press. But there is a thought that comforts the staff of the Yale

Scientific as we attempt to capture such an elusive subject in print. It is the same thought

that comforts the human population as we grapple with our own dynamic growth. As a

publication and as a species, we have commissioned the same photographer to capture

population and provide us with snapshots of what is happening and how we should

respond. It is a photographer that is constantly moving and growing and changing at a

rate equally exponential to the human population: science.

Yale Scientific

Established in 1894

AILMENTS OF A GRAYING POPULATION

How public health is shifting to accomodate the elderly

Decoding

Depression

African Sleeping

Sickness

PAGES 14-17

Hybrid Energy

Harvesters

Jessica Hahne

Editor-in-Chief

About the Art

The cover, designed by Arts Editor Chanthia Ma, depicts

the progression of age using a photo montage. The collage

portraiture begins with the top of a toddler’s head and ends

with the chin of an elderly woman (images adapted from the

photography of Danny Santos II, River Bend Lodge, The

Children At Risk Foundation-Brazil, and Mamy Factory). The

white facial frame creates cohesion among the photographs,

suggesting that the well-being of graying populations is in

direct contact with that of younger generations. Contributing

artists for this issue were Katiya Jindachomthong (page

12), Spencer Katz (page 14), Jessica Schmerler (page 18),

Rachel Lawrence (center spread), Renusha Indralingam (page

23), Casey McLaughlin (page 26), Jason Liu (page 29), and

Qiaonan Zhong (page 32).

PSYCHOLOGY

Psychology Professors Wagner and Nolen-Hoeksema

Honored with Lifetime Achievement Awards

BY CRISTAL SUAREZ

The Association for Psychological Science (APS)

recently named Allan Wagner, the James Rowland

Angel Professor Emeritus of Psychology, and Susan

Nolen-Hoeksema, the former chair of the department,

recipients of lifetime achievement awards.

Wagner received the William James Fellow Award,

which celebrates “significant intellectual contributions

to the basic science of psychology.” Wagner’s research

focused on associative learning, which he described

as the “process whereby one event reminds one of

another.” Exploring the mechanisms behind associative

learning, he contributed to the development of

Pavlovian conditioning models such as the Rescorla-

Wagner model (co-authored with

Robert Rescorla of the University of

Pennsylvania).

Later models worked to clarify

characteristics of learning that previous

studies had not fully described.

For example, they addressed how

subsequent appearances of a stimulus

IMMUNOLOGY

IMAGE COURTESY OF THE APS

APS celebrates its 25th

anniversary this year.

School of Medicine Professors Flavell and

Medzhitov Awarded Vilcek Prize

Awarded annually by the Vilcek Foundation to an

immigrant researcher who has made lasting impacts

on American society, the Vilcek Prize in Biomedical

Science will be shared this year by two Yale scientists.

Sterling Professor of Immunobiology Richard

A. Flavell joined Yale to found the Department

of Immunobiology, of which he is currently chair.

Among other accomplishments, Professor Flavell

helped develop a Lyme disease vaccine, showed that

DNA possesses noncoding intron regions, and generated

a more accurate mouse model for studying the

immune system. At Yale, his work has served to elucidate

many intricate workings of the innate immune

system, the body’s first defense against pathogens.

Ruslan M. Medzhitov, David W. Wallace Professor

of Immunobiology, became interested in the innate

immune system early in his career when he read Dr.

Charles A. Janeway, Jr.’s paper proposing its existence.

After joining Janeway’s laboratory at Yale in 1994,

Medzhitov made several groundbreaking findings,

including his discovery of Toll-like receptors that

recognize foreign molecules and activate the innate

immune system. This breakthrough helped launch the

BY JIAHE GU

are not processed and responded to as effectively

when that stimulus is already in active memory.

“Today’s problems are suggested by yesterday’s

solutions,” Wagner said. His work on the fundamentals

of associative learning has influenced areas of

study as varied as the development of causal judgments

in humans and the neurobiology of eyeblink

conditioning in rabbits.

Nolen-Hoeksema, who died on January 2 of this

year, received the James McKeen Cattell Fellow

Award. The award acknowledges “outstanding contributions

to the area of applied psychological research,”

and is awarded to members whose “research addresses

a critical problem in society.”

Nolen-Hoeksema’s research focused

on mental health and included work

on mood regulation. She facilitated the

understanding of gender differences in

depression and worked to direct her SUBJEC

findings into active efforts to intervene

in the development of mental illness.

IMAGE COURTESY OF GAMIL DESIGN

Vilcek Prize trophies are individually designed

by Stefan Sagmeister.

study of the innate immune system, until then largely

unrecognized, into prominence.

Academic honors are often viewed as crowning

achievements, but we can be sure that these two giants

will continue making great discoveries for decades to

come. “It’s a very wonderful thing to be recognized,

and I certainly do appreciate it, but we have to step

back and remember what we’re doing, which is trying

to understand how the world works,” said Flavell.


BY ANDREW DEVEAU

ENERGY

Economics Professor Discusses

Overstimation of Energy “Rebound Effect”

ECT

In a piece published in Nature in January, Kenneth

Gillingham, Assistant Professor of Economics at the

Yale School of Forestry & Environmental Studies,

argues that the size of the “rebound effect” — the

bounce in consumption following

a decrease due to improved efficiency

— is often overestimated.

To visualize the rebound effect

at work, suppose American automobile

manufacturers develop

more fuel-efficient cars. Because

each gallon of gas provides more

mileage, gas is relatively cheaper

and people are inclined to drive

more. Second, some of the money

saved on gas will be spent on other energy-consuming

goods. Additionally, improved efficiency might spur

economic growth, which consumes energy. And finally,

if American demand for oil decreases, oil will become

cheaper globally, increasing consumption abroad.

Some argue that these effects are so significant that

any increase in efficiency is sure to backfire, increasing

rather than decreasing energy consumption. This

would mean that “energy efficiency policies would not

cut our energy use at all,” said Professor Gillingham.

However, by examining macroeconomic

data and conducting

studies on consumer responsiveness

to changes in efficiency and

prices, Professor Gillingham has

shown the size of the rebound

effect to be exaggerated. In the

IMAGE COURTESY OF SCRIPPS COLLEGE

Professor Gillingham’s work

combines economics and

environmental science.

developed world, the rebound

effect results in only between a 20

percent and 60 percent reduction

in savings. Gillingham emphasizes,

therefore, that setting efficiency standards could

remain an effective way to confront the problem of

energy consumption. The debate over energy policy

rages on: there has already been a counterargument

to Gillingham’s piece published in the February issue

of Nature.

Professor Handelsman Named One of Nature’s

“Top Ten People who Mattered” in 2012

IMAGE COURTESY OF HOWARD HUGHES MEDICAL INSTITUTE

Professor Handelsman works with a student

investigating bacteriology and plant pathology.

BY ELIZABETH ZHANG

SOCIOLOGY

Jo Handelsman, Frederick Phineas Rose Professor

of Molecular, Cellular, and Developmental Biology,

was recently featured by Nature as one of the “Ten

People Who Mattered” in 2012. The article, “366 Days:

Nature’s 10,” demonstrated the acute international

response to Handelsman’s research in gender bias.

In August 2012, Handelsman and Dr. Corinne

Moss-Racusin, a postdoctoral fellow in psychology,

published in the journal Proceedings of the National

Academy of Sciences their results on gender bias in the

scientific community. Handelsman explains their motivations:

“Scientists would typically say, ‘[gender bias]

doesn’t apply to us, even though it applies to every

other group in society. It doesn’t apply to scientists

because we’re trained to be objective.’ And it made

Corinne and I say, ‘okay, let’s answer the question

with the data.’” In their study, 100 scientists were

given applications from fictitious male and female

undergraduates seeking jobs as laboratory managers.

The results were unequivocal and shocking: Employers,

male and female alike, consistently considered

female applicants less competent, offered them lower

salaries, and were more likely to withhold from them

career-building advice. “I was not surprised by our

findings per se, but by how robust the findings were,”

said Moss-Racusin.

The study has since then gained international recognition,

“even without the help of the Nature feature,”

Handelsman said. The study continues to motivate

her to eliminate bias by holding educational training

sessions for employers. She believes that even modest

efforts in the classroom, such as students bringing up

the study with their professors, can help alleviate the

worst effects of bias.

www.yalescientific.org April 2013 | Yale Scientific Magazine 7

NEUROSCIENCE

Uncovering The Biochemical Basis For Depression

BY SMITA SHUKLA

A staggering 40 percent of individuals afflicted with depression do not

react to popular antidepressants, which are usually selective serotonin

reuptake inhibitors (SSRIs). Although depressive episodes have often

been attributed to serotonin deficiencies, researchers at the Yale School

of Medicine recently discovered that other systems are likely at work.

“The acetylcholine system could also play a role in depression,” said

Marina Picciotto, the Charles B. G. Murphy Professor of Psychiatry and

Professor of Neurobiology and of Pharmacology, and senior author

of a new study, published in the Proceedings of the National Academy of

Sciences in February. First author Yann Mineur is an Associate Research

Scientist in Psychiatry at the Yale School of Medicine.

The Picciotto Laboratory had examined the acetylcholine system

before, particularly in connection with smoking. Their work focused

on the nicotinic acetylcholine receptors, which are the primary sensors

for the neurotransmitter acetylcholine. These receptors can be found

at the neuromuscular junction, where they mediate communication

between nerves and muscles. However, in the brain, the acetylcholine

system is much broader and more complex — for instance, acetylcholine

may either activate or inhibit cognitive processes based on its location

within the brain.

Nicotinic acetylcholine receptors activate during smoking, and there

is a known connection between smoking and depression. Picciotto

explained, “human smokers who have had a previous episode of depression

find it much harder to quit smoking, while those with no previous

history of depression may encounter their first episode after quitting.”

Withdrawal from smoking can account for a change in mood, since

changes in the activation of nicotinic receptors can generate a brain

imbalance that can contribute to depressive episodes.

In order to further understand how nicotinic acetylcholine receptors

affect mood in humans, the researchers developed a model for depression

with genetically altered mice. They found that regardless of nicotine

exposure, mice were less depressed when a blocker for acetylcholine was

present. Researchers thus inferred that the presence of this neurotransmitter

may play an integral role for depression in mice.

Research in the 1970s showed an analogous result in human subjects,

uncovering a relationship between acetylcholine and depression.

This existing knowledge about tobacco, acetylcholine, and depression

provided the motivation for the researchers to directly investigate the

connection between acetylcholine and depression.

To explore this theory, the researchers used a test for antidepressent

effects, where mice with varying levels of acetylcholine were placed in

a pool of water from which they could not escape. Normally, in similar

situations, mice have a positive reaction to stress and continuously search

for an exit. However, with higher levels of acetylcholine and greater

depression-like symptoms, mice displayed just enough motivation to

keep their noses out of the water.

As a follow-up experiment, researchers then used a top-down

approach by observing the effect of common SSRI antidepressants on

mice with depressive symptoms. These mice were less stress-sensitive

and reacted more normally — that is, they actively sought to escape the

stressful environment.

Additionally, the researchers determined that the major region of

IMAGE COURTESY OF THE MAYO FOUNDATION

These scans depict significant reduction in neurotransmitter

activity in brains of patients with depression.

the brain undergoing acetycholine changes resulting in symptoms of

depression was the hippocampus, which is associated with motivation

and emotions in both mice and humans. By increasing the amount of

acetylcholine in just the hippocampus, scientists could observe effects

throughout the body. This finding in particular gives researchers a

potential area of the brain in which to manipulate the genes involved

in depression.

Mineur and Picciotto also collaborated with colleagues in the Yale

Department of Psychiatry on a study where human subjects with varying

degrees of depression were given a tracer that competed with acetylcholine

for the nicotinic acetylcholine receptors. As expected, people with

chronic depression showed fewer sites for the tracer to bind, meaning

that either there was more competition for the receptors due to higher

concentrations of acetylcholine, or that these individuals had a decreased

number of acetylcholine receptors to begin with. The researchers

disproved the latter notion by examining post-mortem cortical tissue

from the Canadian brain bank. Brains from depressed individuals had

the same numbers of receptors compared to brains from people with

no history of depression, implying that the decreased tracer binding in

the imaging study was due to competition with acetylcholine for binding,

and that depressed individuals tend to have higher concentrations

of acetylcholine.

The implications of this research are vast, though the pathways

involved in motivation and mood regulation are just starting to become

understood. But by pinpointing the exact biochemical system involved

during the development of depression, researchers might eventually

be able to provide more effective cures than the currently used SSRIs.

“We’re interested in how stress regulates activity of neurons and whether

we can understand that using genetic techniques or other manipulations

in the mouse,” Picciotto said. In the near future, researchers hope to test

new antidepressants targeting acetylcholine receptors in the human brain.


BY ELIZABETH HIMWICH

ASTRONOMY

Researchers Find a New Planet in the “Habitable Zone”

In January, researchers with Planet Hunters confirmed with 99.9

percent confidence the discovery of a Jupiter-sized planet called

PH2b orbiting within the “habitable zone” of its star, the range where

Earth-like planets could have liquid water and possibly sustain life.

The researchers also announced 42 new planet candidates, including

20 located in the habitable zone of their respective stars.

Planet Hunters is a collaborative project designed by Yale University

and Zooniverse, an online collection of citizen science projects, that

allows citizen scientists to search for exoplanets — planets orbiting

other stars — using data from the National Aeronautics and Space

Administration Kepler space telescope public archives. Its “streamlined

interface allows volunteers to look at a light curve in 5-10 seconds,”

said Dr. Debra Fischer, Professor of Astronomy and co-founder of

the project. Users examine the “light curves,” or star brightness levels,

for possible planet transits, which are indicated by a dip in light curve

brightness when a planet passes in front of the star.

“Many other events can also produce these signals,” said Dr. Ji Wang,

a postdoctoral associate and lead author of the paper about the discoveries.

“Once we rule out false positives, planets can be confirmed.”

“The planet PH2b itself cannot sustain life because it is a gas planet,”

said Wang, “but this kind of gas giant usually has many satellites — take

Jupiter and Saturn as examples. If the distance of the planet from its

star is right, its satellite could be habitable. Finding a habitable planet

is the first step; finding a habitable ‘exomoon’ is the next step.” However,

detecting a so-called exomoon is extremely difficult because an

exoplanet already has a very shallow transit signal, and an exomoon

would have a signal at least an order of magnitude smaller.

The increased frequency of exoplanet discovery and confirmation

means that “we are now at the beginning of a new age,” said Dr. Meg

Schwamb, a National Science Foundation postdoctoral fellow at Yale

working on Planet Hunters. Now, “we can move on to figuring out our

solar system’s place in the galaxy,” by comparing other solar systems,

such as that of PH2b, with our own.

PH2b, a gas giant, is roughly the same distance from its star as the

earth, a small, rocky planet, is from the sun. “This comparison gives

IMAGE COURTESY OF JI WANG

Light curve data. Black points are from odd-numbered transits,

red points from even-numbered transits. The dips in the light

curve from a star indicate the transit of a planet in front of it.

IMAGE COURTESY OF NASA AND TIM PYLE

An artist’s rendition of exoplanets passing in front of a star.

us an idea of different pathways of planet formation and frequency of

life,” explained Schwamb. “We are getting to the point of comparative

climatology and solar systems.”

These latest findings represent a success for both professional and

citizen scientists working on Planet Hunters. “We present data in a way

that’s accessible to everyone, and we try hard to show the public what

we’re doing, and how we’re doing it,” said Schwamb. “We bridge the

gap between scientists and non-scientists by bringing them in on the

ground level. These discoveries highlight the power of eyeballs — we

have 200,000 friends who can look through the data.”

The Kepler public archive releases data that scientists have already

scrutinized, but Planet Hunters, using the same data, has almost doubled

the number of gas giants found in the habitable zone. Fischer explained

that Kepler, which identifies exoplanets using the transit technique of

monitoring for the drop light due to a planet moving in front of its

parent star, is biased toward finding exoplanets that move faster, produce

large light-curve signals, and transit more frequently These planets

are closer to their stars and thus less likely to be in the habitable zone.

Citizen scientists working on Planet Hunters, on the other hand, can

consider transits on a case-by-case basis, and can visually detect planets

which produce fewer dips in the light-curve; these are the planets with

a wider orbit and a longer orbital period that Kepler algorithms often

overlook. Nine of the recent planet candidates have orbital periods over

400 days, and most have periods longer than 100 days.

“I didn’t expect that volunteers would be able to find a significant

number of planets that the Kepler computers couldn’t. Everything

found by volunteers causes Kepler to improve their algorithms,”

Fischer added.

“We are entering this era of ‘big data’,” said Schwamb. “We need to

find a way to go from gigabytes to terabytes. Machine learning will be

much better with input from citizen science. It can ‘train’ an algorithm

— this is where citizen science is going.”

“This is a fun, exciting question, and the public response has been

incredible,” Schwamb added. “Seeing graphs on a screen doesn’t emotionally

hit you the same way as images of galaxies do, yet people still

come to Planet Hunters — this says something about how excited we

are to find our place in the universe.”


MEDICINE

Nearly one-fifth of Medicare patients discharged from a

hospital (2.6 million seniors in total) develop other medical

problems within the subsequent 30 days that necessitate

additional hospitalizations — many of which are unrelated

to the initial diagnoses.

Professor Harlan Krumholz, a cardiologist and the

Harold H. Hines, Jr. Professor of Medicine and Epidemiology

and Public Health at the Yale University School

of Medicine, and his colleagues examined this staggering

statistic in an article published in the Journal of the American

Medical Association.

While interested in a wide range of medical issues,

Krumholz was drawn to cardiovascular disease because of

its far-reaching effect on the population. Krumholz explains

that as a cardiologist, “you can help patients navigate

through difficult periods of their life when there is a crisis.

You have the opportunity to work with people who have

chronic cardiovascular disease […] and help them manage

it in the long term. You also have a chance to play a role

in preventing cardiovascular disease to the point that the

whole risk of the population decreases.”

Krumholz and his group initially developed the hospital readmission

measures that are used for for public reporting and national incentive

programs. But after looking at the causes and timing of readmissions,

they began to see something unexpected. The observed phenomenon

became what Krumholz dubbed the “post-hospital syndrome.”

The post hospital syndrome is a 30-day period of vulnerability following

a patient’s release from the hospital. During this period, patients

are not only still recovering from their illness, but are also experiencing

a period of generalized risk for a number of adverse medical events.

This period of risk may be the result of cumulative stressors on

patients during hospitalization that can increase their susceptibility

to adverse health events. Numerous stress factors in addition to the

illness include sleep deprivation, malnutrition, pain, cognitive and

psychological pressures, and financial burdens. Abnormal sleep cycles

and the disruption of normal circadian rhythms can negatively affect

the patient’s metabolic function, cognitive performance, physical

condition, and immune defenses. The combination of behavioral and

physiological stresses can increase occurrences of dysphoric mood,

lower physical function, and impair cognitive function.

Nutrition is also a concern: One-fifth of hospitalized patients 65

years of age or older intake less than 50 percent of the nutrients recommended

to maintain their energy requirements. Malnutrition can

lead to an array of medical issues including impairment of wound

healing, increased risk of infections, and reduced system function.

Furthermore, patients suffering from pain can experience sleep

deprivation, abnormal moods, impaired cognitive performance, and

lower immune functions. Pain medications can further affect cognitive

function.

Cognitive stresses like information overload and the erratic,

unpredictable schedules of hospitalscan also affect patients. Many

patients go home with cognitive impairment that can improve over

The Revolving Door of Hospital Readmissions

BY QIAONAN ZHONG

IMAGE COURTESY OF HARLAN KRUMHOLZ

This graph shows the proportions of rehospitalizations for causes other

than the condition at initial discharge.

time — but may be profound at discharge. It is no surprise then,

Krumholz remarked, that “when we try to teach [patients] about their

medication, habits, and behaviors […] they don’t seem to understand

or listen to us.”

Instead of trying to load patients with an abundance of information,

Krumholz suggests that hospitals and doctors change their approach.

“In the midst of trying to treat patients for a life-threatening illness,

sometimes we lose sight of the smaller disruptions that can, as an

aggregate, produce a lot of stress on the patient and have important

consequences,” he said. Hospital administrators and doctors must

work together to address this problem and to recognize all of the

challenges and risks patients face after being released, and not just

the initial diagnosis.

Krumholz recommends teaching patients about post-hospital

syndrome and taking the time to warn them about the implications

of the associated mental and physical impairment. Patients should be

encouraged to find someone else to help them with post-discharge

instructions, to resume daily activities, and to be safe by recognizing

their risk for falls and accidents. At the same time, further research

is needed to characterize this period of generalized high risk. As the

medical community becomes more aware of this syndrome, potential

strategies are being discussed to create test programs that will improve

the patient experience in hospitals as well as smooth their path to

recovery when they go home.

In reflecting on his choice of cardiology, Krumholz said, “[My area

of study has] allowed me to work with healthy people to keep them

healthy and with people who are acutely ill and facing life-threatening

illness. It has allowed me to become involved in a field with both great

public implications and great clinical implications.”

As the response to the post-hospital syndrome grows, the medical

community hopes to minimize the number of avoidable readmissions.


BY MAHBUBA TUSTY

VIROLOGY

Can Viruses Adapt to Erratic Temperatures?

Yale researchers led by Professor Paul Turner of the Ecology and

Evolutionary Biology Department have shown that viruses have

significant difficulty adapting to rapidly changing temperatures.

Although viruses are known for their adaptability under different

environmental conditions, Turner found that they suffer when

temperatures change too unexpectedly. His findings are especially

relevant in the face of the rapid temperature changes predicted by

various climate models. If viruses like the ones which cause the

common cold fail to adapt to temperature changes despite their

simple structure, what does this research imply for other, more

complex animals such as polar bears or even humans?

For this particular project and many others, Turner used the

vesicular stomatitis virus, a popular subject for studies in viral evolution.

It contains only five genes that evolve very quickly, making

the virus ideal for laboratory use. Within a day, Turner produced

four generations of the virus. and eventually created 100 generations

in total for the study.

Turner and his team then divided these viruses into four groups

and assessed their ability to adapt to different set temperatures.

The first group was tested at 37 degrees Celsius, approximately the

temperature of the human body and a standard temperature for

research. Next, the researchers tested another group of viruses at

29 degrees Celsius, the “low temperature” for the experiment. The

third group of viruses was exposed to both the low and high temperatures

on alternating days. Finally, the fourth group in the study

was subjected to erratic temperature changes, where temperatures

ranged anywhere from 29–37 degrees Celsius on any given day. The

goal of the experiment was to assess the phenotypic and molecular

changes of the viruses under the different temperature conditions.

If the viruses underwent significant mutations at their respective

temperatures and produced significant phenotypic change, they

increased their fitness. If they failed to do so, their adaptability and

therefore their fitness

left them susceptible to

destruction.

The results showed

that viruses had the highest

fitness gains in the

alternating, yet predictable

temperature pattern

(group three). Viruses

in the two treatment

groups (groups one and

two) which employed

constant temperatures

IMAGE COURTESY OF UNIVERSITY OF

WISCONSIN-MADISON

Glycoproteins on the surface of the

virus enable invasion into host cells

and may be the most affected by

temperature changes.

had the next highest fitness

gains. The viruses

in the final group, which

encountered the random

temperature changes,

had the lowest fitness

gains. This means that

IMAGE COURTESY OF THE CENTERS FOR DISEASE CONTROL AND PREVENTION

Arthropod-borne viruses, such as the vesicular stomatitis

viruses shown in thie electron micrograph, are used by the

Turner Lab as experimental models.

the viruses exposed to erratic temperatures were the least successful

in adapting and improving their likelihood of survival.

The viral gene that produces glycoprotein, which is responsible

for virus entry into the host cells where it reproduces, seems to

be the gene most affected by the temperature changes. Across all

the temperatures tested, the majority of genome substitutions

occurred there. This suggests that glycoprotein plays a key role

in supporting the viruses’ vitality as temperatures change, though

what that role could be is not yet fully understood. As a result, the

functional role of the glycoprotein in temperature adaptation is

the next area of interest to Turner’s group.

These results would seem to beg the question: Are the kinds of

rapid changes in temperature Turner used in his study prevalent

in the real world? “If you don’t like the weather in New England,

wait a night,” Turner answered. “In many parts of the United

States and around the world, the weather already changes by eight

degrees from day to day.” He added, “if we shift our frame of

reference to the world, the change might not be as astounding just

yet.” However, climate models currently in use or in development

show that these kinds of temperature jumps are certainly plausible.

If viruses, the most adaptable life form known, are unable to

adapt to such changes in temperature, how can other species expect

to do so? If efficient reproductive machines such as viruses cannot

adapt to fluctuations in an eight degree window of temperature

change, then what can the koalas or polar bears of the world do

in the face of climate change? Finally, what does climate change

coupled with Turner’s findings imply about the survival capability

of the human species? Of course, much research is needed to

address these questions, and it is for this reason that Turner urges

the government to allocate more money for basic research at Yale

and throughout the nation. “I worry about the future of scientific

research,” he concluded. “I worry about the world my children will

live in without the discoveries made possible by basic research.”


Waking Up to the

Mechanism of

African

Sleeping

Sickness

“It was entirely serendipitous,”

chuckled Professor Christian Tschudi of the Yale School of Public Health, as he described

a discovery that may prevent African sleeping sickness from plaguing Sub-Saharan

Africa. This disease, also known as trypanosomiasis, kills more than 50,000 people

every year and haunts victims with insomnia and mood changes.

BY STEPHANY SEUNG

YEON RHEE

Tschudi’s group, for the first time in history,

replicated the infectious process

of the disease in a laboratory setting.

Their “serendipitous” discovery that overexpression

of a single RNA-binding protein can

lead to infection has been met with applause by

researchers from all over the world. With the

groundbreaking advance, they hope to devise

new interventions in the near future.

The fatal sleeping sickness is caused by the

parasite Trypanosoma brucei, which oscillates

between the insect vector — in this situation,

the tsetse fly — and the mammalian victim,

which can be human or animal. As a tsetse fly

feeds on the blood of an infected mammal,

T. brucei is transferred from the mammal to the

bloodstream of the insect. Inside the vector,

the parasite undergoes complex cycles of differentiation

and multiplication, until it finally

spreads to the salivary glands of the tsetse fly. T.

brucei then regains infectivity, and is injected into

the bloodstreams of mammals that the fly bites.

Treatment of African sleeping sickness in

its early stages is extremely rare due to the difficulty

of diagnosis. A person who has been

infected may not have any visible symptoms.

Even when a person starts displaying symptoms,

they can be very general. For example,

fever, headache, and joint pain can indicate

sleeping sickness but are also known to be

associated with other maladies such as malaria.

By the time major symptoms such as swollen

cervical glands emerge, the infection has

already advanced to the central nervous system.

Once the infection has reached these advanced

stages, the patient exhibits confusion, changes

in behavior, and disturbances in sleep cycle;

hence the name “sleeping sickness.”

Yet even if infections were to be diagnosed

early enough for treatment, the drugs that exist

are few and far between. Moreover, most of

those drugs are highly toxic, and sometimes

deadly. One such example of a treatment for

sleeping sickness is melarsoprol, a derivative

of arsenic, which kills up to 10 percent of the

patients treated with it.

IMAGE COURTESY OF DOCTORS WITHOUT BORDERS

Sleeping sickness kills over 50,000 people

in Sub-Saharan African every year.

A Remarkable Result

Effective treatment of African sleeping

sickness still poses a great challenge. Most of

the drugs used today were discovered before

the 1950s, but hope remains for the discovery

of a better treatment. However, intervention

may now be possible, thanks to Professor

Tschudi and his lab. All previous studies of

the infectious process have been conducted on

the insect vector itself by dissecting the body

of the tsetse fly and thereby directly examining

the organs for T. brucei. Carried out for

nearly a hundred years, such studies allowed

scientists to study what changes occur during

the infectious process, but not necessarily how

they occur. In particular, the challenge remains

in obtaining quantities of T. brucei from each of

the various developmental stages in the insect

vector’s life. This difficulty hinders researchers

from performing mechanistic studies on the

sequence of events that leads to infectivity.

The replication of the infectious process in

laboratory settings is the first step in answering

that million-dollar question of how the infection

occurs.

Tschudi and his research group have made

headway on this front, by successfully replicating

the infectious process of the T. brucei

in laboratory settings. He began at the same

step as all other researchers, by examining the

12 Yale Scientific Magazine | April 2013


INFECTIOUS DISEASES

body of the infected tsetse fly.

One of Tschudi’s colleagues,

Serap Aksoy, possesses one of

the two tsetse fly colonies in the

United States, and the research

group infected and dissected a

sample of these flies to determine

the biological progression

of the infection. Upon realizing

that RBP6, an RNA-binding

protein, increased by a factor of

13 during the middle stage of the

infectious process, Tschudi and

his colleagues decided to replicate

this observation in vitro. Their initial goal

was hardly to replicate the infectious process,

but simply to study the binding protein. They

induced overexpression of RBP6 to determine

which type of RNA is bound by the protein.

Ten days later, they came upon unexpected

results: the cultured, non-infectious cells had

become infectious cells.

“When I told my colleague George Cross at

Rockefeller University, he was speechless. Then

he finally said, ‘This is the biggest thing that

has happened in the last 20 years,’” Tschudi

recalled. He went on to explain that the fact

“that one single protein can trigger these events

is close to unheard of, not just in the trypanosome

field, but just science in general.” Considering

that the trypanosome genome encodes

around 10,000 proteins, the importance of the

single protein RBP6 is truly striking.

Stopping the Next Domino

IMAGE COURTESY OF GEOFFREY ATTARDO

The tsetse fly can kill people and livestock

in Africa by infecting them with

sleeping sickness.

The replication of the infection process

through the overexpression of RBP6 shed a bit

of light on the stage of the parasite’s life cycle

that has been called the “heart of darkness.” He

explained that this stage transpires as a domino

effect with many potential points of intervention.

In the ten days between the overexpression

and the infection, T. brucei undergoes a

IMAGES COURTESY OF CHRISTIAN TSCHUDI

T. bruce in its infectious state (left) and its non-infectious state (right).

variety of complicated transformations including

a change in physical shape and a silencing of

previously active mitochondria. To understand

the how of the infectious process — how these

transformations are related, and how they ultimately

lead to infection — each domino in the

chain must be studied individually.

Tschudi’s group is in search for a more effective

target point of intervention than the overexpression

of RBP6. He believes that although

the overexpression triggers a sequence of

events that certainly lead to infection, the

RBP6 protein is not directly involved in the

infection. Looking forward, Tschudi hopes

to discover what the overexpression of RBP6

subsequently triggers. “What happens after 24

hours? What changes in the cell? We try to look

at everything globally, analyzing around 5,000

of the 10,000 proteins that technology allows

for,” he explained.

With only two tsetse fly colonies possessed

by U.S. laboratories and the relatively low attention

the disease receives in the medical world,

collaboration is necessary in the trypanosome

field. Tschudi, who came to Yale over thirty

years ago, said that African sleeping sickness

is a neglected tropical disease, as it does not

receive the same level of attention as other

deadly tropical diseases such as malaria. “We

welcome others and have already started collaborations

with people. The more we work on

it, the faster the field moves forward.”

Hopefully, Tschudi’s discovery will help alleviate

some of the negative impacts that sleeping

sickness has wrought. The deaths of human

beings, at around 50,000 per year, is only a part

of the problem caused by African sleeping sickness.

Nagana, the deadly livestock version of

the sleeping sickness, actually has an enormous

economic impact on Sub-Saharan countries.

Tschudi hopes that one day, reduced cases of

nagana will help the economic development of

the impoverished Sub-Saharan African region.

Finding the right domino to remove from the

chain of infection would signify a victory not

only for individuals infected with the disease,

but also against the poverty it perpetuates in

affected regions.

About the Author

Stephany Seung Yeon Rhee is a freshman in Saybrook College and an Electrical

Engineering and Computer Science major. She is the Multimedia Editor for the

Yale Scientific.

Acknowledgements

The author would like to thank Professor Christian Tschudi for his time and enthusiasm

about his discovery.

Further Reading

• Kolev, Nikolay G., K. Ramey-Butler, G. A. M. Cross, E. Ulllu, C. Tschudi. 2012.

“Developmental Progression to Infectivity in Trypanosoma brucei Triggered by an

RNA-Binding Protein.” Science, December 7.


THE FUTURE OF

SPACE EXPLORATION

delving into the final frontier

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by ariel ekblaw

“

easy

because they are , because that goal will serve organize and measure the of our

WE CHOOSE TO GO TO THE MOON.

We choose to go to the moon in this decade and do the other things, not because they are

hard

BEST

In the 51 years since John F. Kennedy’s

Rice Stadium Moon Address, space

exploration has captured the imagination

of several generations in the U.S. and abroad.

His vision articulated goals much grander than

the moon landing, especially

his intention that as the

“exploration of space will

go ahead […] we mean to

lead it.” Have we fulfilled his

mandate?

We now face a changing

landscape for space

exploration, as industry and

commercialization, rather

than government efforts,

claim a growing share of

aerospace development in

the U.S. Pressure from the

burgeoning Chinese space development

program and our recent reliance on the

Russian Soyuz spacecraft to reach the

International Space Station (ISS) have forced

us to acknowledge a globalizing trend in space

exploration. With exquisite advances in robotics

and remote data sensing,

the glorious manned space

missions of the Apollo era

now share the limelight

with distant probes and

unmanned rovers. Through

several rounds of tough

budget cycles and trying

tragedies, we have at times

postponed the challenge

posed to us by President

Kennedy, though the allure

of space exploration reliably

recaptures our attention,

sparking further discovery and innovation.

”

John F. Kennedy

September 12, 1962

NASA’s Evolving Role

Our modern conception of space exploration

was born during the Cold War. The successful

Soviet launch of Sputnik, the world’s first

artificial satellite, on October 4, 1957 spurred

the U.S. government to create NASA (National

Aeronautics and Space Administration) and

place space exploration high on the national

security priority for over three decades of

fervent technological competition.

Now, NASA shares the opportunity for

exploration with circles beyond their core of

career experts. Through their Microgravity

University, the space exploration behemoth

pulls in young talent, giving teams of budding

aeronautical engineers, astronauts, and space

scientists the opportunity to solve NASA’s

current design challenges. Frank Prochaska,

Manager of the Reduced Gravity Education

energies and skills, because that challenge is one that we are willing to accept, one we are

unwilling to postpone, and one which we intend to

IMAGE COURTESY OF THE NASA HISTORY OFFICE

John F. Kennedy delivers his

address to send an American

to the moon by the end of the

decade.

win.

12 Yale Scientific Magazine | November 2013 www.yalescientific.org

, but

AERONAUTICS

Flight Program (RGEFP), creates these

opportunities for the students to “use their

creativity to solve technical problems currently

facing NASA engineers and scientists.”

After months of technological development

in collaboration with a stringent NASA

oversight committee, the students fly their

experiments in a modified Boeing 727 “Zero-

G” aircraft over 30 demanding parabolas of

microgravity, normal gravity, and hypergravity.

Prochaska heralds these youth-centered efforts

as the future of space exploration. As NASA

updates its mission for the 21st century, we can

expect new creativity in their programs, such

as the RGEFP, and a revitalized reverence for

man’s desire to explore.


IMAGE COURTESY OF NASA

Top: Zero-G Parabolic Flight. Bottom:

Members of the Yale Drop Team

study the Raleigh Taylor Instability

in Changing Gravities as part of the

RGEFP.

Throughout NASA’s projects, collaborations

between government technology and academic

research labs stand poised to produce key

discoveries in space science. Yale Professor

of Astronomy Priya Natarajan looks forward

to a promising future for space exploration,

most recently exemplified in the breathtaking

achievement of NASA’s 1977 Voyager probe

as it exited the Solar System. Natarajan hopes

that the probe, after years of loyal service to

the scientific community, will offer captivating

new insights for astrophysics. Reminding us

of the scale of this achievement, and more

to come, she noted that not since the intrepid

explorers of the 1500s has a product of

the human race crossed such a momentous

frontier. For her research on the fundamental

nature of gravity and dark matter, Natarajan

anticipates fruitful future projects with the next

generation of space probes such as LISA, the

Laser Interferometer Space Antenna. Though

NASA has had to step away from LISA due

to funding challenges, the European Space

Agency will take on the mantle of advanced

gravity research in their plans for the New

Gravitational-wave Observatory.

These symbiotic relationships between

NASA technologies and academic research

promise an exciting future — but is this

promise enough? Can the government

muster the economic capital and efficiency

to get man back to the moon? Enter a new

figure in this longstanding relationship: the

space exploration industry. Though private

industry contractors have long played a part

in the development of space technology

(notably Boeing’s long history in aerospace

engineering), the last ten years have witnessed

an explosion of new private space ventures

and companies. From cutting-edge rocket

development to commercial luxury space

flight, each corporation has found its niche

in the market. Now attracting top talent,

these profit-centered industries are taking a

competitive, time-pressured and dramatically

efficient approach to space exploration.

The Rise of the Space Industry

In less than a decade of existence, Space

Exploration Technologies (SpaceX) delivered

a cargo payload to the International Space

Station via their Dragon Spacecraft. As

the first commercial spacecraft ever to

dock with the ISS, the Dragon represents a

successful collaboration with NASA through

the Commercial Crew and Cargo Program.

Through further innovation, the young

company’s recent advances in reusable

rocketry with the Falcon 9 rig will shape a

new paradigm for future launches. In 2012,

NASA announced agreements with three

American space industry companies “to

design and develop the next generation of

U.S. human spaceflight capabilities, enabling a

launch of astronauts from U.S. soil in the next

five years.” Working under the Commercial

Crew Integrated Capability initiative, Sierra

Nevada Corporation, SpaceX and Boeing

were collectively awarded over $1 billion to

develop this new technology. These companies

are revolutionizing space exploration at a

blistering pace and inspiring a new generation

of aerospace engineers, scientists, and space

enthusiasts among the public.

Fundamental to the recent birth of the space

industry, incentivized competitions run by the

X PRIZE Foundation have mobilized public

interest and profoundly advanced the state of

our society’s space exploration ventures. As

stated in their mission, X PRIZE competitions

“bring about radical breakthroughs for the

benefits of humanity, thereby inspiring

the formation of new industries and the

revitalization of markets.” Most influential for

space exploration, the $10 million Ansari Prize

was awarded to Burt Rutan’s SpaceShipOne

team in 2004, after they succeeded in achieving

private suborbital flight two times within two

IMAGE COURTESY OF SPACEX

The reusable “Grasshopper” rocket

system flew to a 250m height with 100m

lateral maneuver and then regained its

initial position on the launch pad.

weeks. The Ansari X Prize is often hailed as an

impetus for innovation in space exploration.

A more recent exploration competition

began in 2007, the Google Lunar XPRIZE

headed by Alexandra Hall. In order to win

the $20 million prize, by December 31, 2015

a private company “must land safely on

the surface of the Moon, travel 500 meters

above, below, or on the Lunar surface, and

send back two ‘Mooncasts’ to Earth.” One of

the companies engaged in the competition,

Astrobotic Technology, has already secured

a contract with SpaceX for a launch on the

IMAGE COURTESY OF THE XPRIZE FOUNDATION

Google Lunar XPRIZE teams compete

to land their craft on the moon, travel 500

meters in some capacity, and transmit

information back to Earth.

Falcon 9 in October 2015.

Director Alexandra Hall predicted that “the

future of space exploration will be one marked

by partnerships of all kinds and involving

disciplines that have not necessarily been

involved with space until now.” Compelling

economic arguments can be made for

November 2013 | Yale Scientific Magazine 13

AERONAUTICS

space exploration through the years

a TIMELINE of MAJOR

ACHIEVEMENTS

1972: apollo 16 moon landing

1984: space shuttle discovery’s maiden launch

2000: international space station first occupied

investment in space technology, as the success

of commercial entities “will lead to businesses,

job growth, and wealth in sectors from biology,

to materials science, to mining and resource

utilization.” Google’s Lunar XPRIZE aims

to breach the frontier beyond Earth’s orbit

repeatedly and at low cost. To achieve this, Hall

prioritizes further developments in lunar orbit

communications and navigation networks,

the establishment of refueling depots at

strategic points in space, and the expansion

of communications networks on earth that

receive signals from space. Commenting on

the impact of the rise of space exploration

industry, Hall noted that “moving the R&D

from just being governments, to including the

commercial sector means that everything from

the amount of risk that we’re willing to take,

to the legal and regulatory infrastructures will

be challenged. All for the good.”

Creativity in the Pursuit of Space

Inventive approaches to space exploration

hardly end with the X PRIZE Foundation.

Planetary Resources, a company dedicated to

asteroid mining, has stated that “harnessing

valuable minerals from a practically infinite

source will provide stability on Earth, increase

humanity’s prosperity, and help establish and

maintain human presence in space.” With

influential industry backers (Google’s Larry

Page, Virgin Galactic’s Richard Branson, X

PRIZE’s Peter Diamandis, and James Cameron

among others) and an expert team of technical

talent, Planetary Resources is surprisingly

well-placed to tackle what would have been an

outlandish sci-fi mission just a few years earlier.

Building up to their asteroid ambitions, they

recently completed their successful ARKYD

Kickstarter campaign, raising over $1.5 million

in the first crowdsourced funding venture

to offer public access to an advanced space

telescope. Space exploration crowdsourcing

is taking off in its own right as the CubeSat

Project, “an international collaboration of

over 40 universities, high schools, and private

firms developing picosatellites containing

scientific, private, and government payloads”

gives everyday individuals the chance to send

small-scale modular projects into space. With

a crowdsourced funding model, the cost is

shared among all the participating members

of a particular cube’s launch.

The Pressure and Promise of Globalization

Complicating this dynamic network of

governmental, academic, industrial, and

now crowdsourced interests within the U.S.,

several other nations have taken steps to

pursue space exploration. China’s proposals

for a new International Space Station by

2020 and a Chinese moon colony soon

thereafter force us to grapple with the political

implications of space technology. Hall stated,

“as space exploration matures, I believe we

will increasingly see the role of governments

and consortia of nations in building out

infrastructure at each new frontier.” Prochaska

concurred, noting that space exploration is a

“phenomenally complicated puzzle and we’re

working internationally with other Government

space agencies” to put the pieces together.

These multinational efforts stand to

incentivize competition, galvanize space

exploration, and advance humanity’s prospects

for the future. As we look to the final frontier,

a diverse fellowship between corporate and

government interests, small-scale and largescale

projects, and research will take us there.

The future of space exploration is bright, and

2009: butterfly nebula from hubble space telescope

About the Author

Ariel Ekblaw is a senior Physics and Math-Philosophy double major in Pierson

College. Currently working with Yale Professor Eric Dufresne on a biophysics soft

matter project, she flew in zero gravity with the Yale Drop Team in 2012. She hopes

to pursue a career in bioengineering for space or astrobiology.

Acknowledgements

The author would like to thank Frank Prochaska, Priya Natarajan, and Alexandra Hall

for their time and thoughtful contributions to the article.

Further Reading

• Yale Astronomy labs web site. www.astro.yale.edu

2012: curiosity rover lands on mars

14 Yale Scientific Magazine | November 2013 www.yalescientific.org

Ailments of a Graying

Population

By William Zhang

Carol Orlando was 65 when her family

members noticed the first changes.

Her social graces began giving way to

a detached brusqueness; her eclectic interests,

to grinding repetition. Gradually, she lost

the ability to care for herself, and her family

assumed roles as her caregivers: washing and

feeding her, and ultimately assisting with all

aspects of her life. Frontotemporal dementia,

an ailment of aging, was taking its toll.

As she descended deeper and deeper into

this malaise, her speech devolved: “your dad

taking dog for walk,” her daughter Wendy

DeLucca recalled her mother casually stating,

entirely unaware of the missing words. Then,

seemingly overnight, Carol — known to be a

caring mother with endless love to spread and

an endless love for conversation — suddenly

stopped talking.

Of course, not everyone progresses like

Carol. She is just one example, the tip of the

iceberg. Aging occurs on a broad spectrum

and can unfold with a variety of symptoms

and other age-related complications, such

as cancer or cardiovascular disease. Diseases

such as cancer, dementia, and cardiovascular

condititions are not developed exclusively as

symptoms of aging, but they do, in many cases,

have far higher rates of occurence among the

elderly. Even without these diseases, aging in

itself can be a taxing process. The vigor of

youth fades away to be replaced by a slower

pace of life, sore joints, deteriorating vision,

and the accompanying loss of touch with the

prevailing culture.

And while these natural changes may be

pressing enough, the mental inertia of dementia

— or the wear and tear of other age-associated

diseases — exponentially compounds

these challenges and exacerbates the difficulty

of the journey for the elderly. Insidiously, these

complications envelop individuals in a state of

spiraling impairment, as DeLucca can testify

to, gradually snuffing out their very essence.

So what can we do? For decades, researchers

have vigorously pursued avenues for the treatment

and prevention of age-related diseases,

yet solutions are still elusive. Recent investigations

run the gamut, from studies of neuronal

function and genome sequencing of centenarians

to examining the relationship between

diet and aging. “If we could find cures [for

Alzheimer’s and other aging-related diseases],

it would solve all of these problems,” Maria

Tomasetti, South Central Regional Director

of the Alzheimer’s Association, Connecticut

Chapter, explains, “so everyone is searching

for them feverishly.”

Though medical answers may be far in the

future, public health research on aging is concurrently

progressing. This work is carving out

solutions to address arguably more immediate

and equally important concerns of improving

quality of life for the elderly, especially while

the biological mechanisms of disease are still

being unveiled. Recent research in this field

points to gaps in our treatment of the elderly

and of age-related illnesses and challenges the

very underpinnings of how we perceive aging.

Seeing the Forest Among the Trees

It is clear that aging and its associated diseases

impact the elderly, and thus public health

has naturally focused on treating patient conditions.

But Joan Monin, Assistant Professor

of Epidemiology at the Yale School of Public

Health, argues that there is a missing factor in

the equation. Behind every elderly individual

facing health complications is at least one other

person taking them to their appointments,

assisting with household chores, aiding them

through the difficulties: the caregivers.

Informal caregivers — those who are unpaid

and are often spouses or children — deliver

80 - 90 percent of personal and medical care

to the elderly with chronic illnesses. Approxi-


PUBLIC HEALTH

mately 22.4 million Americans, or one in four,

are informal caregivers, and the numbers will

only rise as the baby boomers age. The signs of

greater demand are already evident: Tomasetti

notes that the number of calls to the 24/7

caregiver helpline offered by the Alzheimer’s

Association has increased in past years.

The growing demand for caregivers also

places significant strain on the economy and

on our health care system. Recent Gallup statistics

estimate that caregiving results in $25.2

billion in lost productivity, and a wealth of

studies demonstrate that caregiving leads to

negative outcomes in both health and mortality.

In social psychology, such a phenomenon

can be explained by the notion of emotional

contagion: people identify with the negative

emotions around them, which leads to a state

of shared suffering or, as Monin describes,

“

“literal vicarious feelings.”

As her disease progressed, Carol began to

wake up in the middle of the night and rummage

around her home, unable to be calmed.

Situations such as these, along with routine

care and distress, accumulated to a point at

which it became difficult for the caregivers to

take care of themselves. Her husband Richard,

who once generally embodied a “stoic Sicilian”

persona, became quicker to vent his stress

and frustration. And times were no easier for

DeLucca, who felt like she was wearing a veil

every day. Although sometimes it was “thin

and gossamer,” it could instantly become

“thick and suffocating.”

But Monin believes that the hardships of

caregiving can be greatly reduced. “Everyone

suffers though certainly not to the same

extent,” she said. So what is the key to regulating

the extent of suffering? It all boils down

to perspective, Monin proposed — specifically

aspects, such as resilience and cognitive

appraisal, that can be shaped by healthcare

interventions.

In one of her recent studies with arthritis

patients and their caregivers, Monin investigated

caregiver responses to spousal suffering

and quantitatively found perceived suffering

to increase caregiver stress. By bringing both

parties into the lab and recording the patient

walking and carrying a 10-pound bag for three

minutes, she demonstrated that cardiovascular

arousal of caregivers significantly increased

when watching their spouses performing the

task, compared to watching another unknown

elderly person performing the task. With this

“watered-down version of a caregiver’s everyday

life,” as Monin characterized her experiment,

she concluded that caregivers’ perceptions

of their spouses suffering directly affects

their physiological arousal, which in turn

predicts greater depression and poorer physical

health for caregivers. Furthermore, caregivers

tended to overestimate their spouse’s suffering,

exacerbating their stress.

But what does this mean for the aging

patient? Professor Monin explains that caregiver

health and behavior have serious health

We will all grapple with these

natural processes in some form or

another: aging is everyone’s business.

”

implications for the elderly with chronic

disease. In another one of her studies involving

both Alzheimer’s disease patients and

their caregivers, Monin and her team found

that lower levels of trust in the relationship,

measured by attachment style, exacerbates the

symptoms of Alzheimer’s disease. “It is really

important to help caregivers regulate their

IMAGE COURTESY OF JOAN MONIN

Leading caregiver health expert Richard

Schilz models the set-up of Professor

Monin’s experiment. Caregivers manifest

stress with cardiovascular reactivity,

which can explain one of the pathways

through which caregiving leads to impaired

health.

emotions in the face of suffering,” she said.

“Evaluating the state of the relationship, which

involves both the patient and the caregiver,

can help prescribe personalized treatments.”

Caregiver health has been studied extensively

in the past, but what is truly innovative

about Professor Monin’s work is her focus on

the caregiver-patient relationship, evaluating

both parties in her studies and considering

the relationship dynamics in solutions and

treatments for age-related diseases. “Interventions

to date have not been successful maybe

because they tend not to involve both people

IMAGE COURTESY OF NATURE

Throughout history, most human populations have formed a sort of pyramid structure:

a wide base of children and economically productive adults supporting relatively

few and more socially dependent elders. As the world develops, people have

fewer children and live longer. The traditional pyramid is morphing into a rectangle.


April 2013 | Yale Scientific Magazine 15

PUBLIC HEALTH

IMAGE COURTESY OF BECCA LEVY/ORIGINAL FIGURE FROM LEVY ET AL., PSYCHOLOGICAL SCIENCE 20, 296-298 (2009)

Professor Becca Levy has investigated the predicative power of aging sterotypes and

cardiovascular events, including congestive heart failures, heart attacks and strokes.

Association of negative (blue) versus positive (red) age stereotypes held in younger

adulthood to risk of cardiovascular events over 38 years is diagrammed above.

or other family members who may be able

to help,” Monin, who has a background in

relationship studies, suggested. “Interventions

need to be relational.”

Both Tomasetti and DeLucca agree. Tomasetti

stresses that caregivers wrestle with the

process alone because they are not aware of

available resources. To better disseminate

information, the Alzheimer’s Association is

increasing its focus on physicians’ outreach

so that caregivers will be aware of resources

for information and support. “The reality

is that caregiving is bigger than any one

person,” Tomasetti, who is also an informal

caregiver for her father, said. And DeLucca

shares these sentiments. “There needs to be a

better pipeline of information for caregivers:

through the primary care physician, through

a care manager,” she suggested.

Professor Monin not only has clear support

for her studies, but her work as a pioneer in this

emerging field also speaks to a deeper issue:

the tendency to single out aging rather than

recognizing it within its context. She emphasized

the “need to see the forest among the

trees,” or in other words, the need to recognize

that aging is not only about those directly suffering

from medical conditions. Caregivers

are essential parts of this greater context and

serve important roles in the illness ecosystem.

Shaping Beliefs

Becca Levy, Associate Professor of Epidemiology

and Psychology and Director of the

Social and Behavioral Sciences Division at

the Yale School of Public Health, is another

voice in the call for a shift in thinking toward

aging. Specifically, Levy studies the impact of

elderly stereotypes on health outcomes. As a

graduate student, she received a grant to study

in Japan and was struck by the stark cultural

contrast of elderly treatment there compared

to in the United States. It is well-known that

the Japanese boast the longest average lifespans,

and Levy could not help but wonder if

there was a connection between the Japanese

value of honoring the elderly and longevity.

Since this cultural exchange, she has made

many cutting-edge discoveries about the detrimental

impact of negative aging stereotypes,

including adverse outcomes in cardiovascular

health events, memory tasks, and recovery

from disability.

While aging does consist of a combination

of biological factors, Levy explains that the

common understanding of aging is partly a

social construct and that we have created a

“subjective onset of old age.” Stereotypes

about age permeate throughout society and

can be seen in a variety of places, from health

care settings to the entertainment industry.

Levy has found that the internalization of

aging stereotypes starts at youth when people

are not threatened by and thus most vulnerable

to accepting and propagating them. Alarmingly,

these beliefs are subliminally acquired,

as Levy has demonstrated in studies involving

unconscious word priming and its effect on

task performance. Whether we are young or

old, and whether we believe it or not, we are

contributing to the aging process.

DeLucca, who despite her hardships

expresses compassion towards aging and illness,

has witnessed manifestations of negative

stereotypes in acquaintances and relatives.

Some children are embarrassed by their graying

parents and end up “belittling and degrading

them.” Though she sympathizes with the idea

According to the Centers for

Disease Control and Prevention

(CDC), approximately 80

percent of older adults have at

least one chronic condition and

50 percent have two or more.

With the population on the rise

and a rapidly growing elderly

demographic, the situation is

especially dire: Estimates from

Flash Forward

IMAGE COURTESY OF THE TRUTH SEEKER

the CDC project that the U.S.

elderly population will double to

7.1 million by 2030, accounting

for one out of every five Americans.

Ironically, the increased

life expectancy that has resulted

from improvements in public

health now poses a looming

challenge: providing care for a

graying population.


PUBLIC HEALTH

that children may one day have to care for

their parents, she acknowledges that some

others do not feel this way. In fact, DeLucca

admits that many, perhaps unwittingly,

approach aging with little understanding and

patience.

Recent policy debates can also help to

explain the extensive nature of these stereotypes.

In the midst of the economic crisis,

funding debates have fueled what Levy calls

“intergenerational tension,” pitting areas such

as youth education and elderly care against

one another in what she believes is a “false

dichotomy.” Inevitably, financial troubles will

lead to hard decisions being made, but framing

them in this manner may be evidence of

the elusive stereotypes at play. In addition,

Levy’s studies have demonstrated relationships

between TV and social media exposure,

to negative aging stereotypes and health

outcomes as these media outlets readily disparage

aging and rarely highlight empowered

elderly figures. Images portraying the elderly

fumbling around, for example, may proffer a

good laugh today but become damaging to

our health once we inevitably age. In a way, we

are promoting self-fulfilling prophecies as the

negative stereotypes evolve in self-perception.

The steps to adjust stereotypes may seem

ambiguous, but Levy’s findings are already

paving the way for practical solutions on an

international scale. For example, the United

Nations is currently working to strengthen

human rights for the elderly, which will impact

policy on a global level to reduce negative

applications. Several European countries

are also beginning to consider aging in government-level

initiatives. And domestically,

the U.S. government is currently reviewing

“ageism” policies, especially concerning

images in the media and marketing.

Graying with Glory

At an arguably opportune time, these

studies may be pointing to the beginning of

reconsiderations in how we think about aging.

Robert Butler, the founder of the National

Institutes on Aging, echoes these ideas in his

book, The Longevity Revolution. Rather than

thinking of the growing graying population

as a burden, he suggests that we look at them

as an opportunity and take advantage of

what they can offer. In a similar vein, Nortin

Handler begins his recent book, aptly titled

Rethinking Aging by saying that “aging, dying,

and death are not diseases.”

These scholars assert that we need to look

at aging as not necessarily negative. Centuries

of erosion carved out the Grand Canyon,

and the aging of fermented grapes produces

the most treasured wines. Riches of similar

value lie within the world’s graying population

— we just need to be open to finding

this silver lining.

Ultimately, how we act and think now can

have a very direct impact on how we live in

the future. Aging and its associated diseases

are far from solely being problems of the

elderly. We will all grapple with these natural

processes in some form or another: aging is

everyone’s business.

After four years of being mute and living

in a nursing home, Carol passed away on

October 24, 2012. It was undeniably a trying

time for her family, but DeLucca chooses to

remember her mother for everything she was,

to honor her, to share her story. In the spirit

of redefining aging, DeLucca started a blog

documenting her journey with her mother’s

illness and writes in her most recent post not

of the disease, but of her mother as a “selfless

and caring” woman, “an avid bowler,” and

an aficionado of dance and music. She was a

chemist, a teacher, “a survivor.”

About the Author

IMAGE COURTESY OF WENDY DELUCCA

Mother Carol Orlando (left) and daughter Wendy DeLucca (right) pose for a photo

at DeLucca’s wedding in 2004.

William Zhang is a senior Molecular, Cellular, and Developmental Biology major

in Ezra Stiles College. He is interested in aging and neurodegenerative disease.

Acknowledgements

The author would like to thank Professors Joan Monin and Becca Levy, Maria Tomasetti,

and Wendy DeLucca for sharing their stories, expertise, and insights on aging.

Further Reading

• Levy, B. R., Slade, M. D., Murphy, T. E., & Gill, T. M. (2012). Association between

Positive Age Stereotypes and Recovery from Disability in Older Persons. JAMA,

308, 1972-1973.

• Monin, J. K., Schulz, R., Martire, L. M., Jennings, J. R., Lingler, J. H., & Greenberg,

M. S. (2010). Spouses’ cardiovascular reactivity to their partners’ suffering. Journals

of Gerontology: Psychological Sciences, 65B, 2, 195-201.



A Child’s Focus

Breakthroughs in Early

Autism Detection in Infants

By Naaman Mehta

About 10 in every 1,000 children in

the United States are diagnosed

with Autism Spectrum Disorders

(ASD). Research has revealed that many of

the behaviors typical to the disorder manifest

themselves early in development. So the

question becomes, as Professor Katarzyna

Chawarska of the Yale School of Medicine

stated, “Why weren’t we studying signs of

autism in toddlers?”

Chawarska and her colleagues noticed a lack

of specialized clinics for children under three

years of age and decided to open such a clinic

for very young but already symptomatic children.

Recently, her lab discovered a method

of detecting prodromal symptoms of ASD

in infants as young as six months.

A

Autism and Its Roots

most likely a genetic disorder that results from

a plethora of genetic mutations, or epigenetic

factors that leave the DNA unchanged, but

still influence gene expression.

Researchers suggest two likely biological

explanations, though

A

neither have been

proven. First, white matter tracts in the brain

have been linked to ASD patients. The structure

of neuronal networks can be compared

to an interconnected railroad track system,

where white matter tracts are the physical

railroad tracks separating each city’s train station,

or each area of the brain. In individuals

with autism, these railroad tracks have an

atypical width and length: white matter tracts

which lead to uncoordinated brain activity.

This lack of synchronization between brain

B

activity in the frontal and posterior areas

inhibits communication and coordination

between the two brain areas. Recent research

has also shown a physical overgrowth of the

head in many autistic patients, characterized

by speedy growth of the head during early

development immediately after conception

and subsequent slower growth during later

months of development. Despite discoveries

of these symptoms, the biological roots of

4 BIOL PSYCHIATRY ]]]];]:]]]–]]] K. Ch

F(3,245) ¼ 111.08, p .001, and no interaction (p ¼

with ASD spent a lesser proportion of time than the t

All infants spent the least proportion of time looking

in the moving toys condition (Figure 3B). The eff

effect sizes based on marginal means for planned

condition: F(3,245) ¼ 192. 44, p .0001, but no in

Neither the VR (p ¼ .386) nor the RL (p ¼ .4

groups looking at the person (Figure 2B) across

(p ¼ .007), but not RL (p ¼ .321), was significant.

between the ASD and the other groups were d ¼ .33

.34 (HR-TYP), and d ¼ .29 (LR-TYP).

the disorder are still unknown Toys. A group to researchers.

condition analysis on %Toys

effect of group (p ¼ .373) (Figure 2C), a signifi

Autism Detection

.903). As expected, all infants spent the highest

time looking at the toys in the moving toys conditio

contributed significantly to the model.

Many parents take notice of abnormal

4 BIOL PSYCHIATRY ]]]];]:]]]–]]]

social behavior within Attention the first to Facial 18 Features months

K. Chawarska et al. A group condition analysis on %Face indic

of raising their infants, ficantand effect80 of group: percent F(3,245) of ¼ 3.92, p ¼ .009, a

F(3,245) ¼ 111.08, p .001, and no interaction (p ¼ .339). Infants F(3,245) ¼ 88.00, p .001), but no interaction (p ¼

autism cases are detected

with ASD spent a lesser proportion of time than the three remaining with ASD spent a significantly lower proportion of t

groups looking at the person (Figure 2B) across all conditions. by the 2 face years than of the three age. remaining For groups, though

All infants spent the least proportion of time looking at the person between ASD and LR-TYP became marginally signific

in the moving toys condition (Figure 3B). The effect of the VR example, after correcting infants for multiple who later comparisons (Figure 2

(p ¼ .007), but not RL (p ¼ .321), was significant. The Cohen’s d spent more time looking at the actress’ face in the

Autism is a neurological

disorder that is

between the ASD and the other groups were d ¼ .33 (HR-ATYP), d ¼a lack and moving of childish toys conditions bab-

(Figure 3D). E

develop ASD often exhibit

effect sizes based on marginal means for planned comparisons and dyadic bid conditions as compared with

.34 (HR-TYP), and d ¼ .29 (LR-TYP).

and RL covariates were both significant (p ¼ .

defined by impaired

Toys. A group condition analysis on %Toys indicated no bling, .028, crying, respectively). and The gestur-

Cohen’s d effect sizes base

When a baby or child is

effect of group (p ¼ .373) (Figure 2C), a significant effect of means for planned comparisons between the ASD

social interaction. Its

condition: F(3,245) ¼ 192. 44, p .0001, but no interaction (p ¼ing.

groups were d ¼ .32 (HR-ATYP), d ¼ .47 (HR-TYP)

causes are rooted in

.903). As expected, all infants spent the highest proportion of brought (LR-TYP). into a specialized

time looking at the toys in the moving toys condition (Figure 3C). Subsequently, we examined the proportion o

early development, and

Neither the VR (p ¼ .386) nor the RL (p ¼ .427) covariate clinic, looking doctors at the eyes may and analyze mouth. A group cond

contributed significantly to the model.

as the brain is shaped

specific

on %Eyes

face

showed

and gaze

no effect

processing

(Figure 3E), abnormalities and interactionin

effect (p ¼ .412).

of group (p ¼ .065

a significant effect of condition, F(3,245) ¼ 27

immensely by experience,

environmental

ficant effect of group: F(3,245) ¼ 3.92, p ¼ .009, and condition: addition

Attention to Facial Features

A group condition analysis on %Face indicated a signi-

(p ¼ .785) and RL (p ¼ .997) were not significant. Al

more time

to

looking

testing

at the

for

eyesthe

in the two conditions

F(3,245) ¼ 88.00, p .001), but no interaction (p ¼ .595). Infants

factors are also thought B

Figure 1. (A) Frame

with ASD spent

IMAGE from

a significantly

COURTESY video stimulus OF

lower

KATARZYNA with (B) regions

proportion

CHAWARSKA

of interest used

of time looking at psychopathology a social bid (joint attention characteristic

indicated of only ASD. a significant In recent effect of condition, F(3

and dyadic bid) as comp

in analysis. The regions of interest: scene (face [eyes + mouth] person sandwich and moving toys. An analogous analysi

to contribute to the The scene shown on the monitor serves toys as the a background), face stimulus than the person three for (face remaining infants body), groups, toys, in a eyes, given though and mouth. the trial contrast

between ASD and LR-TYP became marginally significant (p ¼ .064)

p .001 (Figure 3F), but no effect of group (p ¼ .08

intensity of the disorder.

At its roots, ASD is the screen, with regions of interest used p in ¼ .002, but no group condition interaction (p ¼ .830). Post hoc

(Image A). The general outline of the main afterfeatures correcting forobserved multiple comparisons by the (Figure infant 2D). All on infants years, the youngest age

and no interaction (p ¼ .785). The effect of the RL

spent more time looking at the actress’ face in the joint attention

andthe dyadic analysis bid conditions process as compared (Image withB).

the sandwich at which significant ASD (p ¼ .026), has but been the effect of the VR cov

comparisons for group effects indicated that infants with ASD (p ¼ .072).

and moving toys conditions (Figure 3D). Effects of VR

spent less time looking at the scene than the three comparison

18 Yale Scientific Magazine | April 2013 and RL covariates were both significant (p ¼ .045 and p ¼

groups (Figure 2A). All infants spent more time looking at the scene www.yalescientific.org

.028, respectively). The Cohen’s d effect sizes based on marginal

in the

means

condition

for planned

involving

comparisons

moving toys

between

(Figure

the

3A).

ASD

The

and

effect

the other

of Discussion

visual

groups

reception

were

(VR)

d ¼

(p

.32

¼

(HR-ATYP),

.007), but

d

not

¼ .47

receptive

(HR-TYP),

language

and d ¼

(RL)

.33

(p ¼

(LR-TYP).

.339), was significant. The Cohen’s d effect sizes based on The study examined spontaneous social mo

PSYCHOLOGY

detectable with certainty was between 12-24

months, but with the work in Chawarska’s lab,

autism detection has reached new frontiers.

Recent research has encountered abnormalities

in the development of white matter

in infants as young as six months old.

Similarly, researchers noted the presence of

larger heads in patients of the same age that

would later show signs of ASD. This helped

Chawarska realize that something concerning

ASD development occurs around six months.

Chawarska began with a simple preliminary

test in toddlers, noting that toddlers of

about 12 months tend to orient themselves

toward human speech and faces. Toddlers

with autism showed a more limited response

to human contact. Chawarska’s lab then

emulated this phenomenon in the laboratory:

They decided to use child-directed speech

and direct eye contact as stimuli and measure

the child’s response to them. The process

was slightly more complicated than this high

level description, for it involved monitoring

the response of six-month-old infants to

dynamic social scenes. 67 “high-risk” infants

and 55 “low-risk” infants, those who had

siblings with ASD and those who did not,

respectively, participated in the trials. During

a given trial, the infants watched a threeminute

video of an actress sitting in front of

four toys and a table of sandwich ingredients.

In the video, the woman would occasionally

look at the child, making use of the “childdirected

cues,” such as a warm smile at the

child or speaking with a “baby voice.” The

gaze trajectories of the infants were recorded,

and the infants were subsequently followed

through the next year of life. At age three, it

was then noted whether the child ultimately

developed autism.

The results of the trials showed that the

babies who would go on to develop autism

rarely focused on the monitor, and if they did,

they focused more on the background of the

screen with the toys rather than the face and

mouth of the actress.

“Decompose the Scene”

Chawarska emphasized that their work

is not nearly complete; researchers must

first “decompose the scene in a controlled

manner and try to understand what is actually

preventing the kids from having a normal

response time; what is throwing these kids

off?” Perhaps there is something in the

speech of the actress the infants who later

develop ASD are insensitive

to, or perhaps they are so overwhelmed

by what is happening

in the screen that they find it

much simpler to stare at the

background. Regardless, these

results are virtually identical to

those obtained in infants aged

14-24 months and already showing

clear symptoms of ASD.

The underlying mechanism

of ASD is still unknown; yet,

scientists have solid hypotheses.

Infants with ASD may have deficits

in the ability to detect and

prioritize which social stimuli are

the most important to process.

Another hypothesis attributes

the lack of attention to the

limited ability of the stimuli to

arouse enough positive emotion

in the infant to enhance

and encourage the infant to pay

attention. A final hypothesis is a

more simplified deficit: Perhaps

the stimuli are changing so rapidly

that the infant is unable to distinguish

between the social and nonsocial aspects, and

thus simply refuses to pay attention. This mixture

of causes, although intricately connected,

results in confounding factors that make the

treatment for ASD even more difficult.

Chawarska explained that the next steps

involve collaboration between the social and

physiological fields of neuropsychology to

eventually develop a treatment and cure for

K. Chawarska et al. BIOL PSYCHIATRY ]]]];]:]]]–]]] 5

Figure 2. Looking time ratios for the four groups (marginal means, 1 standard error) for the scene, person, toys, face, eyes, and mouth regions of

interest across all conditions. p values for planned contrasts are reported with Tukey-Kramer correction for multiple comparisons. y p .065; *p .05;

**p .01; ***p .001. ASD, autism spectrum disorder; ATYP, infants IMAGE with clinically COURTESY significant symptoms OF KATARZYNA (e.g., language or other CHAWARSKA

developmental delay or

abnormal social-communication or repetitive behaviors) evident in the second or third year of life but who did not meet criteria for ASD; HR, high-risk; LR,

low-risk; TYP, infants with no evidence of clinically significant symptoms in the second or third year.

Each graph depicts the subject’s primary areas of

focus within the stimulus.

deficits were present not only in comparison with infants who are

typically developing (both high-risk and low-risk infants) but also

in comparison with high-risk infants who exhibited some ASDrelated

difficulties, suggesting an association of the noted

ASD. The brain is shaped by experience,

and as the brains of infants have yet to be

altered by the world, scientists must work to

understand the genetic basis of ASD in order

to address primary symptoms as early as possible.

In the future, this could mean targeting

the genes responsible for autism. But until

those genes are discovered, scientists must

continue to seek more effective strategies for

early detection and treatment.

About the Author

attentional deficits with the full-blown syndrome rather than

with intermediate phenotypes.

The positive findings regarding limited spontaneous attention

to social scenes in infants later diagnosed with ASD reported in

Naaman Mehta is a sophomore Molecular, Cellular, and Development Biology

and Spanish double major in Morse College. She is currently the Outreach Chair

for the Yale Scientific, and has worked in the McCormick Lab in the Neurobiology

Department studying the mapping of the auditory cortex.

Acknowledgements

The author would like to thank Professor Charwarska for her time and dynamic

explanations of her research. Dr. Chawarska would also like to emphasize the role

of parents who have made this research possible.

www.sobp.org/journal

Further Reading

• Steiner, Amanda, Gengoux, Grace, Klin, Ami, and Chawarska, Katarzyna. 2012.

“Pivotal Response Treatment for Infants At-Risk for Autism Spectrum Disorders:

A Pilot Study.” Journal of Autism Development Disorders. Doi: 10.1007/

s10803-012-1542-8


By William Gearty



Where does the red panda (Ailurus

fulgens) live in the wild? How widespread

is the eastern grey squirrel

(Sciurus carolinensis) outside of New Haven? A

new Wikipedia-style project, termed “Map of

Life,” aims to show exactly that — and much

more. The demo version of the project, developed

in part by Dr. Walter Jetz of Yale’s Ecology

and Evolutionary Biology Department,

will soon combine over 500 million digitized

spatial records on species from numerous different

data sources, making it one of the most

comprehensive spatial biodiversity resources

yet. As Jetz described it, “the ultimate aim is a

public, online, quality-vetted ‘Map of Life’ that

for every species integrates and visualizes available

distributional knowledge, while also facilitating

user feedback and dynamic biodiversity

analyses.” The implications and uses of such a

resource are innumerable, and it is thought that

such an interactive map could eventually aid in

understanding the effects of human-caused

global change on plants and animals.

A New Method for Mapping Biodiversity

Jetz defines Map of Life as “a global, collaborative

infrastructure for mobilizing, integrating

and analyzing spatial biodiversity data.” It

strategically incorporates information from

a number of sources, including the Global

Biodiversity Information Facility (GBIF),

the World Wildlife Foundation (WWF), and

the International Union for Conservation

of Nature (IUCN). These various databases

complement, critique, and inform one another,

producing dynamic layers of biodiversity distributions

overlaid on interactive Google Maps.

“Map of Life is more than a sum of its parts;

what’s transformational is that these different

data types cross-inform each other and help

us piece together the most transparent, robust

representations of species distribution yet

achieved,” Jetz told Nature. The extent of the

records is constantly increasing, and the soonto-be-expanded

current demo version supports

about 46,000 species, including all described

birds, mammals, and amphibians.

The public demo website (www.mappinglife.

org) currently allows users to perform two

different operations: mapping species dis-


ECOLOGY

tributions and getting species lists. The first

operation allows anyone to visualize the distributions

of different species based on the range

maps, point occurrences, local inventories, and

regional checklists of that species. A series of

filters lets you search for species and narrow

results by data type and data source. These

different layers have varying visual styles to

complement and blend with one another. The

second function, species lists, allows users to

select geographic areas ranging from 50 to

1,000 kilometers and receive a list of all supported

species in that range. The results can be

filtered by radius and type of animal. Although

these functions may seem somewhat rudimentary

at the moment, the project is constantly

expanding in extent and functions. With hard

work over the next few years, this new resource

may come out far ahead of any other similar

modern tools.

Making the Map a Reality

When asked by the New York Times what

the inspiration was for the Map of Life, Jetz

cited his days as a Ph.D. student: “As I was

running around forests in Africa, I came to

the realization that I couldn’t really understand

the patterns of species distribution I was

seeing without going to broader and broader

scales — all of Africa, all of the world.” Jetz

stressed the temporal and spatial knowledge,

quality, and availability gaps between different

types of global-scale data sets on climate,

topography, land cover, and species distribution.

He and project partner Rob Guralnick

proposed the new Map of Life in an attempt

to bridge these gaps by incorporating multiple

types of data into one simple and cutting-edge

public resource. “There is an amazing potential

for such a resource to help understand the

remaining knowledge gaps and to support

the monitoring and analysis of biodiversity

change,” Jetz said. His writing outlined the

cyber-infrastructure that would support such

a resource. Unfortunately, there are no typical

federal or agency funding sources for a project

of global scope. Nonetheless, this new tool

has become a reality with the involvement

of Google, NASA, the Encyclopedia of Life

Project, and several international research institutions,

including the University of Colorado

Boulder and the Naturmuseum Senckenberg.

Now that the Map is public, scientists and

governments around the world can use the

information about the geographic distribution

of species to inform conservation efforts and

policymaking regarding climate change and

even the transmission of zoonotic diseases.

In addition to serving these roles, it also helps

to expose holes in existing distribution data

sets so that future biodiversity research can

focus on particular species or specific regions,

further developing the Map. However, for the

Map to continue to grow it must gain traction

in biodiversity circles. As Jetz told Nature, “the

whole idea only works if scientists are keen to

engage and contribute to the effort.” He feels

there is a good chance the project will prosper

because it integrates knowledge in a dynamic

format that is accessible to those making decisions

about conservation.

The Future of the Map of Life

While some are cynical about the creation

of one more type of biodiversity database,

Georgina Mace, a population biologist now at

University College London is optimistic about

the Wikipedia-style approach. The Map of Life

developers hope to integrate tools to allow

for authorized community input and for the

improvement of the data. Such implementations

will provide credible researchers and nonscientists

the ability to edit existing data and

to add new data to the project. Therefore, the

distribution maps will be constantly up-to-date

and accurate. “Having that dynamic upgrading

of the database is really important; otherwise

it will stagnate and nobody will believe it any

more,” Mace told Nature. Jetz says that more

data is on its way. Since its conception in 2012,

the database has already increased from 25,000

to about 46,000 species. Further additions lie

in the future, including select invertebrates and

plants. “If the project continues to grow,” Jetz

About the Author

IMAGE COURTESY OF MAP OF LIFE

An example of the “species distributions”

feature on the Map of Life.

Various ranges of the Bald Eagle are

overlain on a map of North America.

Yellow represents breeding areas, blue

represents non-breeding areas, and

green represents resident areas.

told the New York Times, “it could be an invaluable

resource five or ten years down the road.”

Finally, Jetz wishes the project could be

used for assessing the response of biodiversity

to human impacts like land use and climate

change, but there is a dearth of data from the

past 10 or 20 years, making it very difficult to

analyze these effects. As Jetz stated, “to date,

even much of what we as a society do know

remains unmobilized, non-integrated, unquantified

and underused.” Strong efforts from

the public and from scientific communities in

broadening the extent and applicability of the

Map of Life may be the next step to understanding

and appreciating biodiversity. With

these future contributions, perhaps we will

finally come to understand how the interactions

between humans and other animals impact the

biosphere and the earth we all call home.

William Gearty is a junior Geology and Geophysics major in Branford College,

with a concentration in Paleontology and Geobiology. He works in Elisabeth Vrba’s

lab and in Jacques Gauthier’s lab.

Acknowledgements

The author would like to thank Dr. Walter Jetz for his correspondence, insight, and

enthusiasm regarding the Map of Life project.

Further Reading

• Jetz, Walter, Jana M. McPherson, and Robert P. Guralnick. “Integrating biodiversity

distribution knowledge: toward a global map of life.” Trends in ecology & evolution

(2012).


Population

Dynamics

By Sophie Janaskie

Will Birth Rates Hit The Breaking Point?

In 1 AD, the human population on Earth

was steady at 200 million. In 1804, in

the midst of the Industrial Revolution,

this count passed one billion. In 2011, just

over 200 years later, the population soared

to seven billion.

The air in cities like Beijing and Shenzhen

is thick with pollutants sputtered from millions

of automobile exhaust pipes. The

aquifers under cities in India are drying up as

thousands of wells pump up groundwater to

satiate their citizens’ thirst. In response to a

growing global demand for food, industrialized

farms are replacing small-scale agriculture,

thus increasing the volume of pesticides

and fertilizers released into the environment.

Our exploding population is placing

strenuous and unsustainable demands on our

planet. What does the future look like in such

a world with an expanding population? Are

these processes reversible, and how do we

go about fixing the environmental damages

that have already been done? These are precisely

the kinds of questions that researchers

around the globe, including several at Yale,

are trying to tackle.

Population Dynamics from Malthus to the Modern

Thomas Malthus, a late 18 th -century

demographer, noted astutely that populations

increase rapidly: not in an arithmetic fashion,

but in a geometric one. This realization

greatly concerned him, and he questioned

the sustainability of continuing the existing

population trend. With a current world population

of seven billion growing at 1.4 percent

annually, some quick math will demonstrate

the importance of Malthus’ observation and

the validity of his concern.

Despite current fertility levels being at

an unprecedented low, they still remain

above replacement level at an average of 2.5

children per couple. This trend, along with

decreasing death rates due to advances in

modern medicine and sanitation, has contributed

to the high rate of population growth.

If fertility remains constant at current levels,

population projections from the UN show

that by 2100 the population will reach 27 billion;

but if fertility continues to drop, other

models project population counts anywhere

between six billion to 16 billion by 2100.

Looking towards the future, it is uncertain

which path our population will follow.

Robert Wyman, Yale Professor of Molecular,

Cellular, and Developmental Biology, stated

that “the range [of possibilities] is enormous

[…] but we just don’t know […] and it is

very scary.” In his opinion, the projection

featuring constant fertility is the most likely

to occur, as the other models assume quite

a significant drop in fertility that will prove

difficult to achieve.

The Anthropocene Era: Impacts of an Expanding

Human Population

Both the explosion in the human population

and the increasing prevalence of

technology have led to the start of what has

been dubbed the Anthropocene era, a term

stemming from the Greek roots anthropo-

(human) and -cene (new), that examines the

extent to which human activity has impacted

ecosystems across the planet.

Climate change and loss of biodiversity

have proven to be two of the strongest examples

of many human-induced phenomena. At


DEMOGRAPHY

the start of the Holocene, the pre-industrial

era, 280 parts per million (ppm) of CO 2

existed in the atmosphere. As of 2012, this

number has spiked to 395 ppm of CO 2

. This

massive increase is primarily due to the combustion

of fossil fuels such as coal, oil, and

gas, which are used to power automobiles,

electrical plants, and other utilities. Recent

trends in land use have also contributed to

global climate change, as half of the world’s

original forests have been cleared, thereby

eliminating one of the largest carbon sinks

on the planet.

Professor Wyman, however, is most concerned

about an even more fundamental

resource. “The first thing to give out will be

the aquifers,” he states while expressing his

great concern regarding freshwater scarcity.

As rivers become increasingly polluted, and as

more groundwater is drawn up from aquifers

to meet the demands of an expanding population,

water reserves are bound to eventually

“

run dry. Chennai, a city in the south of India,

has already experienced a number of “water

outages” in the summer months, during

which the local government was forced to

bring in water from surrounding Indian states

to provide for their citizens.

Hope for Ecological Recovery

It is clear that our detrimental behaviors

need to be stopped, but the greater question

is: can we reverse the damage already done?

A meta-analysis by Professor Oswald

Schmitz of the Yale School of Forestry &

Environmental Studies looked at the ability

of ecological systems to recover from human

disturbances and suggested some hope. Contrary

to long-standing perceptions, Professor

Schmitz found that ecosystems “can recover

fairly quickly, in terms of half of a full human

generation.”

According to Schmitz, it ultimately boils

down to human will. A prime example is the

2010 BP oil spill in the Gulf of Mexico. The

incredible amount of publicity surrounding

this event pushed it to the forefront of the

It is clear that our detrimental behaviors

need to be stopped, but the greater question

is: can we reverse the damage already done?

IMAGE COURTESY OF ROBERT WYMAN

When a decline in birth rate lags behind a decline in death

rate, the population experiences a sudden burst in growth.

The rate of this growth is determined by the gap between the

birth rate and the death rate.

”

public’s attention. The general public ended

up contributing a great deal of funds to the

clean-up. “In 20-30 years, things can recover

pretty quickly,” he stated. “The reason

things don’t recover is

that people abandon

them. If we actively

put our mind to it, we

can fix the damages.”

This finding provides

some hope

for the reversal of

ecological damage

that has already

been inflicted. Further

investigation is

required to ascertain

whether this ecological

principle can be

applied to issues such

as water scarcity and

air pollution, which

may not be as selfcorrecting.

Schmitz

does, however, point

out that for the first

Shenzhen, a city in China’s Guangdong

province, has a population of over 10

million. Air pollution often negatively

impacts visibility, causing buildings in

the distance to appear hazy.

time in history, humans are shifting their

populations from rural areas to cities. In

some countries such as the United States

and China, the urban population exceeds the

rural population. As more people aggregate

into cities, there is a large amount of ongoing

research to determine how to effectively

carry out sustainable city development and

growth. By taking advantage of the clustering

of people in concentrated areas, resource use

may be reduced. The building of sustainable

cities may thus be able to reduce our negative

impacts on the environment moving forward.

Consumption and Population Growth

PHOTO BY SOPHIE JANASKIE

There is more to the story here than sheer

population growth. As the global economy

continues to develop, people are coming to

expect higher standards of living that are

often more resource-intensive. Thus economic,

cultural, and consumption-related

factors must also be considered in order to

properly contextualize these environmental

concerns.

As societies across the world become

increasingly globalized and economies continue

to develop, it is anticipated that everyone’s

ability to consume is going to increase.

One argument is that it is not the number of

people, but rather their level of consumption



DEMOGRAPHY

PHOTO BY SOPHIE JANASKIE

As more drains empty wastewater into

this river in Guangzhou, pollutants accumulate

and affect the clarity, flow, and

usability of the river.

that is the issue. Americans make up only 4

percent of the world population, and yet are

responsible for 25 percent of the resources

used globally. “What we have to do is think

about needs and wants and consumption,”

said Professor Schmitz. “We have to have a

conversation about when enough technology

is enough. [This problem is] not a population

issue directly, but rather a consequence of

people wanting a high standard of living.” In

his opinion, we as consumers must begin to

think more consciously about the resources

we waste, and companies must innovate ways

to recycle within the already existent material

stream.

Professor Wyman, however, asserted

that consumption is only an issue because

our numbers are so large. If there were still

200 million people on the planet, we would

be much less concerned with our levels of

consumption. He stresses the aggregate

global consumption rather than individual

consumption. In his mind, the only true

solution is reduction of the world population.

Future Actions: Moving Forward

Reducing energy, water, and resource

consumption through conservation, efficiency,

and green technologies are important

steps in minimizing the effects of a growing

human population. However, Norman

Borlaugh, who won the

Nobel Peace Prize for his

work in developing new

plant strains that became

the basis of the Green

Revolution, stated in his

acceptance speech that

“there can be no permanent

progress in the battle

against hunger until the

agencies that fight for

increased food production

and those that fight

for population control

unite in a common effort

[…] United they can win a

decisive and lasting victory

to provide food and other

amenities of a progressive civilization for the

benefit of all mankind.” There are a number

of ideas regarding how to achieve this control

of the population.

“In order for the world population to

stabilize, fertility has to come down,” said

Professor Wyman. To do this, the birth rate

must be lowered by “elevating the autonomy

of women to make life-changing decisions for

themselves” through personal empowerment,

education, and access to contraception. More

than two-fifths of pregnancies worldwide

are unintended, and data show that if these

pregnancies were avoided that the average

global childbearing numbers would immedi-

About the Author

IMAGE COURTESY OF ROBERT WYMAN

This graph of world population (billions) versus year

demonstrates different world population projections according

to different variants. In the constant-fertility variant,

the population would reach 27 billion by 2100.

ately fall below those of replacement fertility.

“The difference is quite significant […] about

a child and half,” said Wyman. “You don’t

have to change hearts and minds […] Family

planning is the low-hanging fruit.”

There is an urgent need for change. Our

rapid population growth — to the tune of

one billion people every twelve years — has

had substantial effects on the environment,

modifying and shaping it in unprecedented

and large-scale ways. If the human population

continues to increase this rapidly and no

action is taken to mitigate its effects, the environment

will continue to bend and strain until

the earth finally reaches its breaking point.

Sophie Janaskie is a sophomore Environmental Engineering major in Ezra Stiles

College. She is on the board of the Yale Public Health Coalition and works as a college

coordinator at the Office of Sustainability.

Acknowledgements

The author would like to thank Professor Wyman and Professor Schmitz for their

time and enthusiasm about their research.

Further Reading

• Harrison, Paul, Fred Pearce, and American Association for the Advancement of

Science. Aaas Atlas of Population & Environment. Berkeley, CA: University of

California Press, 2000.

• Jones, H. P., and O. J. Schmitz. “Rapid Recovery of Damaged Ecosystems.” [In

eng]. PLoS One 4, no. 5 (2009): e5653.

• Pearce, Fred. The Coming Population Crash and Our Planet’s Surprising Future.

Boston: Beacon Press, 2010.



Inhibiting

Infection

Rates

Inhibiting

Infection

Rates

BY CHRISTINA DE FONTNOUVELLE

Imagine that HIV rates in crowded cities

could be reduced with a single public

health program. Imagine that this program

could make both its users and police

safer. Imagine that this program is incredibly

simple and cheap.

Now realize this: such programs exist, yet

they are so controversial that few American

cities reap their benefits and the government

refuses to fund them. Upon hearing

their names without knowing the facts

behind them, it isn’t hard to imagine why.

They are syringe exchange programs, which

provide clean needles to drug users at no

cost.

HIV/AIDS and Injection Drugs

In cities, contaminated drug syringe use

is one of the most common mechanisms

of HIV transmission, causing 30 percent

of HIV infections outside Sub-Saharan

Africa. Whenever an addict injects heroin or

cocaine, the syringe retains trace amounts

of blood. While these droplets are miniscule,

they contain millions of HIV particles,

easily enough to infect anyone else who

uses the syringe again. When faced with

withdrawal and a shortage of syringes, drug

addicts often feel trapped and are forced to

use dirty syringes.


This problem has become the focus of

research for many public health professionals,

including Yale Professor of Epidemiology

Kaveh Khoshnood. Khoshnood became

interested in syringe-transmitted HIV

as a graduate student in New Haven. For

his Master’s thesis, he conducted a smallscale

study on New Haven drug users with a

focus on identifying barriers to methadone

treatment program. For his Ph.D. dissertation

research, Khoshnood conducted a

study evaluating the utilization and efficacy

of New Haven’s syringe exchange program.

Khoshnood wanted to continue this

research and demonstrate that syringe exchange

programs are powerful tools in slowing

the spread of HIV. In a five-year study,

he and his colleagues recruited close to

1,000 drug users in New Haven; Hartford;

and Springfield, Massachusetts. While New

Haven and Hartford have syringe exchange

programs and pharmacies that sell syringes

over the counter, Springfield does not.

“We wanted to learn the ‘natural history’

of syringes in these cities, so to speak,”

said Khoshnood, including “where they

come from, how they are used and discarded,

what are the various influences on

this natural history, where disease risks are

introduced.” By tracing syringes and surveying

drug users, the researchers found that

in Springfield, syringes were used over and

over again by many different people much

more often than in New Haven or Hartford.

Springfield also had a higher rate of HIV in

drug users than the two other cities did. The

syringe exchange programs and access to

syringes through pharmacies were working.

Recruiting and obtaining meaningful

survey responses from all 1,000 drug users

was not an easy task. “Drug users have been

shunned and stigmatized by society and are

distrustful of any authorities that try to approach

them,” said Professor Khoshnood.

“It took a long time to establish trust with

drug users, but they learned that our intentions

were not to harm them. My prior

experience with research on drug users as a

graduate student was useful in this respect.”

Drug users are wary of authorities for

good reason. Many are known to police,

which makes them prone to pat-downs

when walking the streets. The fear of being

arrested reduces clean syringe use, even

when syringe exchange programs are available

— being caught with syringes, even

clean ones, can serve as evidence of illegal

drug use. Many addicts thus choose to avoid

carrying clean syringes and take risks with

used syringes later when they cannot quickly

obtain clean ones. Thus, criminal issues carry

over into public health, and Khoshnood


EPIDEMIOLOGY

found that to address the health issues, he

had to consider the criminal ones as well.

The Law versus Public Health

During his work on syringe exchange

programs, Khoshnood heard a lot more

about the police than he expected to. “We

realized that we needed to talk to the police,

and somehow coordinate what we are trying

to do with what they are trying to do,” said

Khoshnood. “The police have a duty to enforce

the law, and we are trying to improve

public health, but these two approaches are

not necessarily harmonized.”

Khoshnood and his colleagues talked

to various police departments about the

reduced efficacy of syringe exchange programs

due to drug users’ fear of being arrested

if they carried syringes on them. The

Volunteers run a syringe exchange program

in Chicago.

researchers had varying levels of success,

depending on the police chief. For instance,

in Springfield the police officers were “completely

uninterested and had no flexibility at

all. They even threatened to arrest our staff.”

In New Haven, however, police officers

gave the researchers flexibility and allowed

them to conduct their studies and distribute

clean syringes with “their blessings.”

Khoshnood and his colleagues were even

invited to train with the New Haven police.

“They are sympathetic to our cause to some

extent, but there’s a limit to their flexibility,”

said Khoshnood. “If they catch a drug user,

it is their duty to arrest them. Nevertheless,

trainings and dialogues are very important.”

Training sessions with police served

to show police the benefits of syringe

exchange programs to themselves. For instance,

one of a police officer’s greatest fears

is being stuck by a contaminated syringe

while patting someone down. Because these

programs reduce the risk that those syringes

are contaminated, officers were sympathetic

to the idea.


IMAGE COURTESY OF STEVE LISS/GETTY IMAGES

From Papers to Policy

The ultimate goal of any epidemiologist,

according to Khoshnood, is having his or her

research translated into policy. Unfortunately,

this rarely happens, and when it does, it takes

a long time to have an effect. “We’ve had

success from time to time,” said Khoshnood.

“For the past 20 years, there was a ban

on allowing government funds to be used

for syringe exchange programs, which the

Obama administration finally repealed in

2009. Research from our group and others

was used to provide overwhelming evidence

that these programs reduce HIV rates but do

not increase drug use.”

However, Khoshnood emphasizes that this

change was “by no means a happy ending.”

It took 20 years for this ban to be lifted, and

now that it’s finally gone, syringe exchange

programs still do not receive government

funding because Congress has not allowed

funds to be allocated.

Administration and government also

slow down public health research itself.

Khoshnood said the most difficult part of

research is the bureaucracy involved. “From

developing, to conducting, to implementing,

there is a lot of administrative red tape

to slow down public health research,” said

Khoshnood. “Often it is quite difficult to

do highly innovative research. Most senior

colleagues say you have to keep it simple in

a research proposal — you can’t get too creative,

or else you won’t get funded.”

Yet Khoshnood makes clear that creative

thought still definitely has a place in the field

of public health. Sources of funding other

than government grants, such as the Bill and

Melinda Gates Foundation, are often willing

to support research that is less mainstream.

Yale students, including needle-clad

Rhodes Scholar Helen Jack ’12, protest

the ban on syringe exchange programs.

And one of the most common sources of

new creative ideas, in Khoshnood’s experience,

is students.

“I love having students involved, having

fresh ideas and asking a lot of questions,”

he stated. “Every once in a while new ideas

come up that we wouldn’t think to bring up

among our peers, and these questions can

bring new insights to the field.”

Looking Forward

As the results of studies such as

Khoshnood’s become increasingly wellknown

and publicized, he hopes that as many

people as possible will realize that syringe

exchange programs drastically decrease HIV

incidence rates without increasing drug use.

If Congress finally does allow federal funds

to be allocated, syringe exchange programs

have the potential to become widespread

in America, curbing HIV transmission and

shrinking the 30 percent of HIV infections

due to contaminated syringes. As the world

becomes increasingly crowded, simple solutions

to persistent problems such as syringe

exchange programs will be key to maintaining

healthy populations.

About the Author

IMAGE COURTESY OF PHR STUDENT BLOG

Christina de Fontnouvelle is a freshman in Berkeley College and a Layout

Editor for the Yale Scientific. She works in Dr. Yongli Zhang’s lab characterizing the

dynamics of proteins using optical tweezers.

Acknowledgements

The author would like to thank Professor Khoshnood for his time and enthusiasm

in sharing his research.

Further Reading

• Khoshnood, K. The Regulation of Research by Funding Bodies: A Wake-up Call.

International Journal of Drug Policy 17: 246-247, 2006.


FEATURE

MODERN SCIENCE

Power In Numbers

The Growing Citizen Science Movement

BY TIERNEY LARSON

Working together certainly has its merits; two heads are almost

always better than one. But what about 250,000 heads?

Modern research is much more than simply admiring stars through

a telescope or brewing concoctions in a lab. Data analysis, categorization,

and pattern recognition are all integral parts of the scientific

process. However, sometimes the manpower, or even computer

power, of a single lab is just not enough to tackle an entire project,

let alone complete it in an efficient manner.

As the value of including as many people as possible in various

fields of scientific research has become increasingly recognized,

crowdsourcing has come into play. Crowdsourcing utilizes the Internet

as a platform for collaboration. Scientists can put their projects

on the web, and anyone who wants to get involved can volunteer to

perform simple tasks. Formally known as the citizen science movement,

organizations have emerged around the globe within the last

six years, creating websites that serve as headquarters for researchers

to post their projects. Anyone can log on, choose a project of interest,

and play an active role in the scientific process. The best part?

There are no deadlines and absolutely no prerequisites.

Before becoming popularized via the Internet, the citizen science

movement began with projects like the annual Audubon Christmas

Bird Count, which took place in December 2012 for the 113 th time.

Volunteers are asked to go into their backyards, count the birds they

see over the course of 15 minutes, and send their results to the Audubon

Society where conservation biologists analyze population trends.

Since then, citizen science has evolved into programs spanning all

disciplines of science. OldWeather, for instance, is a project where

volunteers transcribe old weather records from nineteenth century

ships in order for

scientists to investigate

climate trends. There

are numerous astronomy

projects such as

PlanetHunters, where

volunteers have successfully

identified new

exoplanets. Opportunities

such as SnowTweets

(mapping snow

accumulation across the

country), Project: Play

with Your Dog (analyzing

human-dog interaction

through a cognitive

science perspective), and

even Bat Detective (listening

to and classifying

bat call recordings) can

all be instantly accessed

online.

Citizen science allows

people to catch a glimpse

of the realm of scientific research. The public is given a chance to

discover what research entails and to share in the excitement of a

world that does not usually receive much exposure — the “behind

the scenes” part of science. Most citizen science projects have the

appeal of a video game with the added value of making a meaningful

contribution, letting users participate in scientific discovery while

sitting on the couch in their pajamas.

The Citizen Science Alliance, a group of scientists, software developers,

and educators who collectively operate these Internet-based

projects, stresses the importance of the movement from a scientific

perspective as well. There are overwhelming advantages to embracing

the power of the Internet to include the public in research efforts.

With the expansion of modern technology, data sets have multiplied

in size, allowing researchers to work with more information than ever

before. Computer programs have become exceptionally sophisticated

to handle the data influx, but inherently human abilities, primarily

pattern recognition and the uncanny ability to pinpoint irregularities,

have yet to be perfected by any computer. Therefore, the human

brain is an invaluable tool in the scientific process.

“It’s really a win-win situation,” commented Dr. Meg Urry, Yale

professor and newly elected president of the American Astronomical

Society. Urry is part of the team that operates GalaxyZoo, the

first project launched on the Zooniverse, which is the homepage of

the largest, most popular citizen science projects on the web today.

Established by the Citizen Science Alliance, the Zooniverse attracts

hundreds of thousands of people each day to log in, participate in

projects, and even blog with the scientists about their experiences.

The pioneer program, GalaxyZoo, garnered more attention than

expected and skyrocketed

the citizen science

idea to success. Urry

explained that the basic

idea of the program is

quite straightforward,

appealing to those who

have been “turned off

by the tedium of rote

learning before having

the chance to do real

research.” Users go on

the site, take a short

tutorial, and are asked to

classify images of galaxies

based on their shape.

In its first six months

Galaxy Zoo provided

the same number of

IMAGE COURTESY OF GALAXYZOO

When citizen scientists log onto GalaxyZoo, they can flip through images of

galaxies and describe what they see while classifying shapes and noting irregularities

along the way.

classifications as would

a graduate student working

around the clock for

three and a half years.

“With computers you


MODERN SCIENCE

FEATURE

IMAGE COURTESY OF OLDWEATHER

A popular citizen science program called OldWeather provides volunteers with written weather records recovered from ships

that kept logs in the nineteenth century. The human ability to translate written reports is a skill almost impossible to replicate

with a computer program.

can enforce consistency…but GalaxyZoo compensates by having

thousands of people participate,” said Urry. With thousands of

people classifying one galaxy, scientists can compare answers to draw

more accurate conclusions based on the majority consensus. Also, the

individual performance of each user can be tracked. Site managers

are able to analyze click speed and ratio of correct classifications,

so any user found randomly clicking around will have their answers

unweighted, again allowing for more accurate classifications.

Urry added that with GalaxyZoo, “consistency and bias could

have been a big flaw, but this proves to be why it’s so valuable.”

Although human bias and lack of experience with the material at

hand may seem like pitfalls, there is a major upside to incorporating

public opinion. People are able to call attention to irregularities that

might go undetected in a computer program designed to strictly

follow certain guidelines. In 2009 GalaxyZoo participants made a

breakthrough discovery of a brand new class of galaxies by noting

that it was not characteristic of the pre-set types — something a

computer would never have been able to do. Using the findings,

computer programs can later be improved to pick up on irregularities,

improving technology in the long run.

Some critics argue that citizen science is not actually real science

at all but rather a way for researchers to have other people perform

tedious or unpleasant work. While it is true that all projects are based

on forms of pattern recognition or data collection, the fundamental

principle of citizen science is that the projects are a volunteer effort.

Amateurs are an important part of science because they bring a fresh

view and enthusiasm to the field. Furthermore, although participants

are not certified scientists, their contributions remain an integral part

of the scientific process; these seemingly menial tasks are crucial

to each project and add to the overall understanding of the topic

at hand. By providing a chance for people to experience scientific

investigation, citizen science opens doors for those who might have

never received the chance to be involved with science.

The growing movement is truly an instance of science adapting to

modern society. Crowdsourcing brings accessibility and interactivity,

transforming the face of science for both the public and the professionals

who reap the benefits. Moreover, citizen science continues

to gain momentum as there seems to be an endless supply of new

scientific research along with plenty of people eager to make their

own contributions. Two heads may be better than one, but 250,000

heads? Now that’s a game changer.

ART BY JASON LIU



FEATURE

NEUROSCIENCE

Is Google Ruining Your Memory?

The Science of Memory in the Digital Age

BY JARED MILFRED

Is France larger or smaller than Transalpine Gaul? What is the

source of the Danube River? Where, geographically, is Mount Blanc?

These questions, straight from an 1869 Ivy League entrance exam,

are strikingly different from those of the SAT. Today, no collegereadiness

test would ask this kind of question. It seems frivolous to

ask students to think back to geography class and try to remember

whether their teachers ever mentioned the answers. If a 21 st -century

student ever needed to know, his or her reaction would be automatic

— just Google it.

Science can explain why we have grown increasingly reliant on

Internet search engines like Google. Groundbreaking psychology

research is giving us insight into how modern technology affects our

memories. It seems that pervasive

access to information has not only

changed what we remember; it has

changed how we remember. At

least that’s what Dr. Betsy Sparrow,

Assistant Professor of Psychology

at Columbia University, believes.

In a recent study published in

Science, Sparrow and her colleagues

performed four experiments that

demonstrate how our brains have

adapted to technology. In one

experiment, researchers tested how

well subjects remember information

that they expect to have later

access to, as people might with

information they know they could

easily look up online. Subjects were

given 40 pieces of interesting trivia:

Some were completely new facts like, “An ostrich’s eye is bigger than

its brain,” and others were facts that subjects may have known generally,

but not in detail — for example, “The space shuttle Columbia

disintegrated during re-entry over Texas in Feb. 2003.” Each subject

then typed the facts into a computer. Half the participants were told

that the computer would save what was typed. The other half believed

the entries would be erased.

After the reading and typing phases, all participants were asked to

write down as many of the statements as they could remember. Subjects

were substantially more likely to remember information if they

believed they would not be able to find it later. The implications are

far-reaching. For example, if a professor posts lecture slides on the

Internet, students may be less apt to remember information because

they know that they can look up the information later if the need arises.

Next, the researchers attempted to determine whether the Internet

has become, in some sense, an external memory system for those who

use it. This phenomenon is called transactive memory and has been

known to happen in long-term relationships, group work environments,

and other situations where people rely on others to remember

information for them. While we like to imagine the human memory as

having unlimited storage capacity, in truth, we have evolved to offload

By providing ubiquitous access to information, Google is changing

not only what we remember — it is changing how we remember.

information onto other people, like family and coworkers, as well as

other mediums, like handwritten notes and books. Sparrow wanted to

know whether we employ the Internet in the same way.

“If asked the question whether there are any countries with only

one color in their flag,” Sparrow wrote, “do we think about flags — or

immediately think to go online to find out?”

The results were surprising: researchers found that subjects paid

more attention to computer and Internet-related words when faced

with difficult trivia, suggesting that our brains are primed to think

about computers when we encounter questions that we do not know

the answer to.

Sparrow’s two other experiments yielded interesting results as well.

In one, Sparrow found that when

we learn facts under the impression

that we will not be able to

easily look them up in the future,

we become better at spotting

differences between those facts

and similar ones we are shown at

a later time. In the other, when

the researchers asked subjects to

remember a trivia fact and which

of five computer folders it was

saved in, Sparrow was astonished

to find that people were significantly

better at recalling the folder

than the fact itself. “That kind

IMAGE COURTESY OF MINDTECH SWEDEN

of blew my mind,” she said in an

interview with the New York Times.

These results suggest that our

memory patterns have indeed

changed, but the Internet itself is not the sole culprit. Smartphones

and tablets, too, have tremendously increased the ease and speed

with which we can access information. And wearable computing is

just around the corner—Google has invested millions of dollars in

developing glasses with an integrated transparent digital display that

augments reality by providing continuous information overlain onto

what the user sees. If devices like these ever become as ubiquitous as

smartphones, our society could be profoundly altered. College examinations

today commonly test for knowledge comprehension. Perhaps

one day, such tests will be as outdated to our future counterparts as

geography on an Ivy League admissions test is to us.

Sparrow’s work raises broader questions, too. Pervasive access to

information is clearly making society better in some ways. Many argue

that it leads to a more educated populace, more capable scientists, and

better informed political decisions. But at some point, society should

question itself. In adopting the mentality of constant information at

our fingertips, are we leaving something important behind? When we

reduce how much information we hold in our brains, do we diminish

the potential for subconscious reasoning and human insight? Answers

to these important questions remain elusive, but more work like Sparrow’s

will hopefully lead us in the right direction.


BIOENGINEERING

FEATURE

A New Weapon in the Fight Against Disease

When Dr. Rick Haselton, Professor of Biomedical Engineering at

Vanderbilt University, visited a hospital in India, he was shocked at the

inefficiency of health care. Since rural areas did not possess the necessary

tools, a patient would have to trek hundreds of miles and spend

days waiting in a crowded public hospital — all for a simple blood test.

This problem occurs in other countries, too, as the medical resources

of developing countries often remain meager at best. However, thanks

to research by Haselton and other scientists, new cheap yet ingenious

devices have begun to mitigate those shortcomings. In 2011, Haselton

and his colleagues at Vanderbilt developed the “Extractionator,” a

novel and relatively simple apparatus for diagnosing malaria.

A mosquito-borne disease that kills more than half a million people

per year, malaria traditionally is diagnosed by examining blood samples

under microscopes

in hospital labs.

This makes diagnoses

particularly

tricky in places like

Africa, where access

to well-equipped

hospitals is limited.

Though increased

global investment

in malaria prevention

has helped fund

networks of health

workers and provide

products like insecticide-treated

nets,

a method of quickly

detecting malaria

has remained out of

reach until recently.

Diagnosing Malaria With Magnets

BY BRENDAN SHI

IMAGE COURTESY OF VANDERBILT UNIVERSITY

Ray Mernaugh, Rick Haselton, and David Wright have developed a simple and costeffective

way of using magnets to diagnose diseases like malaria.

Enter the Extractionator,

which was

funded by a $1 million

grant from the Bill & Melinda Gates Foundation for the development

of a “low tech, high science” blood testing device. Haselton’s

initial design was remarkably simple. First, the patient’s blood sample

was stored in a thin tube that contained tiny magnetic beads, each

coated with nickel. The nickel could then bind to a specific protein

that is produced by malaria, called histidine-rich protein 2. This way,

a large magnet sliding along the length of the tube could remove the

beads and any bound malarial proteins from the rest of the blood.

As an individual bead with bound malarial proteins moved through

the tube, chemicals in the successive chambers would remove any

contaminating molecules from the bead-protein combination. Further

down, the protein is separated from the bead in a chamber that binds

a salt to the nickel. The final product, the purified protein, is placed on

a diagnostic chip that could detect the protein. In this way, the Extractionator

could determine whether a blood sample contains malaria.

The fully automated, new, and improved Extractionator that Haselton

and his researchers market today is even easier to use: The only

human-operated step is insertion of the blood sample. Not only is it

convenient, but the Extractionator is also very accurate in its diagnosis.

As David Wright, one of the professors working on the project,

explained to the Vanderbilt press office, “[Current] tests are not very

effective because they lack sensitivity… the Extractionator could

ensure that only the people who have malaria are treated.”

While Haselton’s device currently identifies malaria only, this is still

a major achievement. Now, instead of traveling for days to reach the

nearest hospital, people can use the Extractionator to test their blood

for malaria. Furthermore, the technology behind the device can be used

to detect other pathogens as well by coating the magnetic beads with

different substances. Tuberculosis DNA, for example, binds to silicon.

By coating the beads

with silica instead of

nickel, the Extractionator

could be used to

determine whether

someone has been

infected by tuberculosis.

“In the future

we want to develop a

coating that will target

20 different targets in

a single sample,” said

Dr. Ray Mernaugh, the

third principal investigator

on the project,

in an interview with

Vanderbilt.

Haselton’s device

is one of several lowcost,

blood-based tests

that can be used in

developing countries.

Dr. Wei Shen,

a chemical engineer at Monash University in Melbourne, Australia,

designed a low-cost, easy to use blood type test which, like the Extractionator,

can be interpreted by non-professionals. He indented a piece

of paper with the letters A, B, and O and filled the letters with the

corresponding antibodies. Because a specific blood type carries an

antigen that reacts and bonds with the corresponding antibody, the

blood clumps up if the antigen and antibody are a match. Hence, if

type A blood is introduced, it binds to the antibody contained in the

letter A, reporting the blood type.

Haselton and Shen’s devices place the power of diagnosing disease

in the hands of the patients themselves, saving them time, effort, and

money. As their availability grows more widespread, people in many

developing countries will no longer have to travel far and wait in long

lines to receive simple blood tests for crippling diseases like malaria.

Hopefully, as scientists start to do research in this field, devices like

these will proliferate, helping to solve the world’s health problems.



FEATURE

NANOTECHNOLOGY

Capturing Electricity from Thin Air

BY KEVIN BOEHM

Energy exists all around us — in the motion of a heartbeat, the

fluorescent light in an office building, and even the flow of blood cells

through the body. These individual units of energy are relatively small,

but they are numerous. Dr. Zhong Lin Wang, Professor of Materials

Science and Engineering at the Georgia Institute of Technology, has

developed a way to harness this ambient energy. After months of

work, Wang and his team have developed the very first hybrid cell,

which is capable of harnessing both motion and sunlight. By tapping

into multiple sources of readily available energy, the tiny cells have

the potential to revolutionize the way we power our devices.

All of our electronic devices, from medical sensors to calculators,

require a constant supply of energy. Currently, the most common

methods are a plug and power supply or batteries, both of which

are large and thus limit miniaturization. Since Wang’s cell is small

enough to work on the nanoscale, it can readily be incorporated into

biomedical sensors, cellphones, and other small electronics. The cell’s

hybrid design is an advantage as well. Solar energy alone produces

high voltages but is unsuitable for devices used in the dark, while

energy from ambient motion is more consistent but is only available

on a smaller scale. By combining these sources, Wang’s device can

provide a highly reliable supply of electricity.

Wang developed the motion-harnessing component of the hybrid

cell in 2006. Devices called nanogenerators can collect energy at the

micro- and nano-scales of motion by relying on piezoelectricity, the

production of a current from compression or strain. To construct a

nanogenerator, Wang grew a vertical array of microscopic zinc oxide

(ZnO) wires on a flat base. On top of this, he placed an electrode

with multiple pointed peaks that give it a “zig-zag” appearance. When

the ZnO nanowires are bent out of their ordered formation, they

generate small electric charges due to piezoelectricity. They then touch

the zig-zag edge of the electrode, which collects all of the electricity

to produce a current. Due to its sensitivity, a nanogenerator can

capture even vibrations of very small magnitudes, which can then

be harnessed to power an object such as a pacemaker. In fact, nearly

IMAGE COURTESY OF NANO NEWS NET

Wang’s device relies on incredibly thin zinc oxide nanowires,

which are arranged in a vertical array to harvest light and

ambient motion.

ART BY QIAONAN ZHONG

a milliwatt of mechanical energy exists in each cubic centimeter of

the ambient environment.

Many devices, however, cannot be sustainably powered by nanogenerators

alone. Solar cells generate a larger voltage more practical

for use in bright environments. To miniaturize solar power capture,

Wang made use of an existing technology called a dye-sensitized solar

cell (DSSC). These cells are made by combining an anode with an

electrolyte solution to form a semiconductor. First, a dye is applied

to the anode to make it sensitive to light. When light strikes the dye,

it releases electrons that flow through the anode toward the electrolyte

solution, generating a current. Wang’s method employs the same

principle on a miniaturized scale. Dye-coated ZnO nanowires serve

as the anode, surrounded by the cell with a chamber of electrolytic

fluid, forming a DSSC small enough to integrate with a nanogenerator.

After refining both technologies in collaboration with Dr. Xudong

Wang of the University of Wisconsin-Madison, Wang has discovered

a way to incorporate both nanogenerators and DSSCs into a device

he terms a “hybrid cell.” The upper layer of the cell harvests light

energy, and the nanogenerator below collects ambient motion. A

single layer of silicon is sandwiched between the two and functions

as an electrode for both devices, combining their energy into a single

output. The two sources can be connected in parallel for higher currents

and in series for higher voltages.

Even in the absence of light or motion, the circuit can still be

completed. This is highly desirable because it generates electricity

based on what is available. The hybrid cell captures what it can from

the environment, but is not limited by the absence of one source.

Furthermore, although the nanogenerator alone produces a low voltage,

combining it with the solar cell boosts the overall voltage of the

device. These complementary sources allow the device to efficiently

use energy resources in a variety of environments and situations.


NANOTECHNOLOGY

FEATURE

Hybrid energy harvesters are well suited to power implantable

medical devices and other small electronics. In particular, Wang has

proposed the installation of hybrid cells on sensing devices that gather

information about the environment. This would replace traditional

macroscopic sensing and provide more points of data for analysis.

Using this richer data source could revolutionize fields such as environmental

temperature studies, military reconnaissance,

medical endoscopies, and underwater exploration.

However, there are many factors that must be

addressed before this technology can be deemed

dependable enough to power life-saving medical

devices and other valuable electronics. One major

problem is consistency, since solar energy cannot be

harvested within an organism due to the lack of light.

Additional complications arise from the ZnO wires in

the nanogenerator. They are not all of the same length,

resulting in some wires that are too short to touch the

zig-zag electrode and others that are too long to flex

and produce a current.

Wang and his team are working to address these

challenges. To improve the nanogenerator component,

Wang anticipates increasing the wire density to result

in greater power output: If there are more wires per

unit area of the substrate, there will be more electricity

generated. Researchers are also investigating devices

that can harness other sources of energy, such as

thermal and chemical, and be incorporated into the

cell. Biochemical energy — using enzymes to catalyze

energy-yielding reactions — is particularly attractive

due to its prevalence inside an organism where light

energy is low.

The integration of two energy-harnessing methods is

the true genius of Wang’s work. As the movement for

IMAGE COURTESY OF ZHONG LIN WANG

A hybrid cell in series conformation showing how the nanogenerator and solar cell are combined. The layer of silicon in

between the two portions functions as a shared electrode.

self-powered electronics gains momentum, future combinations may

harness thermal, biochemical, and other energy sources depending

on the device’s location. Each energy source has its own limitations,

but integrating multiple collectors into one device leads to efficiency,

reliability, and sustainability. It may not be so long before our iPods

are powered by the steps we take during our morning jogs.

IMAGE COURTESY OF GARY MEEK

Here, Dr. Wang holds fibers containing nanogenerators. Woven into clothing,

these fibers could power devices using energy from our daily movements.



FEATURE

MYTHBUSTERS

Debunking Science: Cryopreservation

BY YIGIT YORULMAZ

From Star Wars to Futurama, science fiction just would not be complete

without cryopreserving a couple of heroes. In the real world, the

concept of freezing humans is similar to that of food refrigeration: low

temperatures limit the rate of chemical reactions that damage tissue,

which theoretically can extend a tissue’s lifespan. Although we have yet

to freeze entire humans and revive them centuries later this idea has

promising applications in the preservation and storage of human organs.

IMAGE COURTESY OF WIKIMEDIA COMMONS

Cryopreservation would enable hospitals to store organs for

extended periods of time, making transplants more accessible.

Organs are a high-demand, low-supply resource. In the United States,

only 28,000 organs were transplanted in 2012, but over 100,000 patients

are still on an organ transplant waiting list. Given their incredible value

in improving and saving human lives, efforts to better preserve organs

are paramount. Currently, organs must be transplanted within hours

even when they are kept in cold storage. However, if scientists could

develop a method to freeze them, their deterioration could be delayed

for months, and hospitals could start banking organs for future use.

There are a number of barriers to cryopreservation. Despite a few

notable exceptions, complex tissues cannot be preserved for extended

periods of time. One major problem is the detrimental effect of freezing

on cellular fluid flow. At below-freezing temperatures, the water between

cells freezes first, and the extracellular fluid becomes more concentrated

with metabolites and proteins as the volume of liquid water decreases.

To counterbalance this change, water rushes out of the cell, creating a

buildup of extreme pressure. When more than two-thirds of the water

has left the cell, its structure irreversibly collapses. Scientists are thus

investigating the role of natural cryoprotectants, such as glucose and

glycerol, which prevent cell collapse by reducing the concentration

gradient between the exterior and interior of the cell.

Another issue is the tissue damage caused by thawing. Slow thawing

leads to the formation of ice shards which can puncture cells. Furthermore,

when ice crystals melt, they create small pools of water in the

extracellular spaces of tissues which disturb the cell’s osmotic balance

and ultimately lead to cell swelling.

Belgica antarctica, an Antarctic fly which is the world’s southernmost

insect, may hold the solution to osmotic balance problems. The fly’s

larva lives for two years in Antarctica while mostly frozen and spends

the remainder of its life cycle on the continent as well. Although it does

have elevated levels of cryoprotectants, including glycerol and glucose,

what seems to ensure its survival are membrane proteins called aquaporins

that regulate the flow of water in and out of cells. These proteins

remove most of the water from the fly’s body. Thus, by simply decreasing

the amount of water in its body, the midge effectively minimizes the

damage caused by freezing and thawing. However, this solution is much

less practical for humans because of the strain that dehydration places

on cells. In addition, while midge larvae can survive with more than 70

percent water loss, humans cannot survive after losing more than 15

percent of their body water; thus, it remains prohibitively difficult to

dehydrate organs, let alone entire humans.

Other examples in nature make scientists hopeful. For instance,

Stanford University graduate student Art DeVries found a protein

in Antarctic fish that enabled them to swim in water as cold as -1.9

degrees Celsius without freezing solid. Due to its repeating structure,

the antifreeze protein (AFP) can bind to ice crystals and inhibit their

growth into larger crystals, effectively lowering the freezing temperature

of some organisms to -2.5 degrees Celsius. AFPs have also been identified

in other organisms, including snow fleas, beetles, and caterpillars.

Although applying AFPs to mammals is more challenging because

they maintain distinctively high body temperatures, there is at least

one case in which scientists have successfully utilized this technique

to improve heart preservation time. In 2005, a group led by Dr. Boris

Rubinsky of the University of California, Berkeley and Dr. Jacob Lavee

of the Sheba Medical Center in Israel preserved rat hearts in a fish

IMAGE COURTESY OF KONRAD MEISTER

A species of Antarctic fish contains a specific antifreeze protein

that prevents the buildup of large ice crystals within its body.

AFP solution. Cooling the hearts to -1.3 degrees Celsius extended their

preservation time from four hours to 21 hours.

Nature can be a valuable mentor: although cryopreservation presents

a number of microfluidic challenges, many creatures have evolved techniques

to tackle them. With further research, current studies that focus

on smaller tissues in animal models may eventually be applied to human

organs. Finally perfecting the technique of human cryopreservation may

take decades, but the allure of preserving life keeps scientists motivated.


GENE THERAPY

FEATURE

For the three million Americans who experience heartbeat irregularities,

expensive and bulky pacemakers may soon become a thing of

the past. In a December 2012 study led by Dr. Nidhi Kapoor at the

Cedars-Sinai Heart Institute, researchers found a way to use geneticallymodified

viruses to turn normal heart cells into specialized pacemaker

cells. With further development, this breakthrough could one day serve

as a simple, effective alternative to the implanted electronic devices that

patients rely on today.

This newly-developed technology is based on the heart’s natural

pacemaker, a specialized region called the sinoatrial node (SAN). The

SAN sends an electrical signal throughout the cardiac muscle to

stimulate contractions — or, heartbeats. While an

adult heart contains over ten billion cells, only

ten thousand of them are in the SAN.

If this small but critical population

of cells stops functioning properly,

the entire heart can fail

to beat.

Currently, patients with

irregular heartbeats are

treated using electronic

pacemakers, which

are implanted in the

upper chest and are

connected to the

heart using electrode

sensors. By detecting

the electrical

activity in the heart

and sending out electric

signals when necessary,

these devices mimic

the activity of natural

pacemaker cells. However,

the risks of infection and

tissue damage from the surgical

implantation, as well as the high cost

of the device, make a biological alternative

to the pacemaker very attractive.

Using a Virus to Jumpstart the Heart

Thanks to viral gene therapy, such an alternative

may now be feasible. Viral gene therapy involves

harnessing a virus’s natural ability to infect cells with

its own DNA; with some modification, the virus can

be used to “infect” cells with therapeutic genes instead. In Kapoor’s

study on pacemaker cells, scientists took advantage of this technology

to create new pacemaker cells by using a virus to deliver a critical gene,

Tbx18. According to Dr. Omar Samad, a Yale neuroscientist who studies

applications of viral gene therapy for neuropathic pain, the method was

particularly effective because “viral gene therapy works for well-defined

conditions that could be corrected by a specific gene, in this case Tbx18.”

In addition, the approach “would have fewer side effects because it

is specific to a particular gene, can be delivered to specific areas, and

perhaps most importantly, is long-lasting,” Samad said.

The protein that Tbx18 encodes is known to play a role in the differentiation

of SAN pacemaker cells by binding to DNA at certain sites

and promoting the production of other critical proteins that regulate

SAN development. Thus, it is essential for the proper growth and differentiation

of SAN cells. By using a virus to express Tbx18 in normal

heart cells, called myocytes, the researchers hoped to trigger the production

of proteins which would turn the myocytes into pacemaker cells.

The results of initial experiments testing this hypothesis were highly

promising. When the genetically-modified virus was added to a culture

of myocytes, the team found that about ten percent of the cells started

sending electrical signals just like those of actual SAN cells. Additionally,

the cells began to closely resemble pacemaker cells, taking on

their long, spindle-shaped form. The transformed

myocytes even developed new modifications

in their DNA that affected the expression

of SAN cell-related genes.

After successfully transforming

normal myocytes into

pacemaker cells, researchers

began tackling a larger

question: would the same

technique be effective

in living organisms?

To this end, the

researchers injected

the virus directly into

the hearts of live

guinea pigs. Then,

after two to four

days, they suppressed

the natural heartbeat

and found that the new,

transformed pacemaker

cells were able to compensate

and keep the heart

beating. This discovery shows

that the viral gene therapy method

was able to induce SAN cells in vivo,

representing a major step towards a new

treatment for use in humans.

For Kapoor and his colleagues, the prospect

of using the technology in human

patients is a hopeful one. In addition to

testing the long-term viability of the induced

pacemaker cells, the group plans to experiment with large-animal models

before eventually moving to human clinical trials. During this process the

safety of the virus vector will remain a central issue. “Any therapy that

interferes with the genome could have permanent effects,” says Samad.

“We need more studies to know that in the long run gene therapy does

not cause unwanted genetic alterations leading to cancer.”

Nonetheless, Samad considers the development very promising,

noting that clinical trials involving other viral gene therapies have already

been conducted. If further concerns about safety and long-term viability

are addressed, the viral therapy could become a highly effective treatment

for patients who need pacemakers.

IMAGE COURTESY OF THE UNIVERISTY OF COLORADO DENVER

Electronic pacemakers are currently the

main treatment for irregular heartbeats.

BY GRACE CAO



FEATURE

Sam Spaulding, JE ’13

BY MARGARETTA MIDURA

Not many people can say that they have communicated with robots,

worked for Disney, and graced the stages of both Jeopardy! and Who

Wants to be a Millionaire?. But for Samuel Spaulding, a senior Computer

Science major in Jonathan Edwards, this is simply the beginning of

a promising future in social robotics.

As a member of his high school math and Quiz Bowl teams,

Spaulding’s interest in science started early. His interest in artificial

intelligence, specifically, was sparked during his senior year after

reading the book Gödel,

Escher, Bach: An Eternal

Golden Braid. However, it

was only when he came

to Yale that he became

interested in computer

science.

“When I first got here,

I’d never taken a computer

science course,”

Spaulding recalled. “But

freshman year I took

this Intro Programming

class, really loved it, and

thought ‘Okay, computer

science is something that

I can really get into.’”

Drawing inspiration from

his interest in cognitive

science, Spaulding eventually

found a field that

combined both of his

interests — applying

artificial intelligence to

robotics.

At the Yale Social

Robotics lab, Spaulding’s

UNDERGRADUATE PROFILE

Spaulding spoke about the nature of intelligence at the 2013 TedxYale

Conference.

research involves finding

ways for humans and

robots to interact comfortably

with one another through spoken language. “The idea first

came when I was thinking, ‘How can you make interactions between

humans and robots more natural?’” Spaulding said. “Language is

the most natural way that humans communicate. It’s what we use

to communicate with each other. Speech technology like voice recognition

and synthesized speech weren’t good enough in the past

to justify working with, but they have been improving so rapidly

that it’s feasible to think now about this type of interaction.” Thus,

one of Spaulding’s goals is to teach robots about the environment

around them using speech.

In a project that culminated in his senior thesis, Spaulding created a

robotic system that adjusts its behavior depending on the verbal input

it gets from the user. After hearing the user describe an object, the

robot can identify the object and establish a sentiment score based

on what the user says about it. Something that the user describes in

a positive way would therefore be assigned a higher sentiment score

than something described negatively. Afterwards, the user will ask the

robot about the object at hand. For example, the robot may be asked,

“How do you feel about carrots?” The robot then selects behaviors

to execute that are socially appropriate, given the sentiment score

it has learned for carrots from the user’s description. By teaching

robots how to react to objects that they encounter, this undertaking

provides a step towards improving human-robot communication.

In addition to working in the Social Robotics Lab, Spaulding has

been putting his computer

science skills to use in various

ways. In the summer of

2011, he worked at Amazon

to develop a website that

assessed team performance.

The experience gave him

valuable programming experience

and showed him

how a standard software

engineering company functions

on a grand scale. Furthermore,

he worked on a

team to create an Android

app called SmileIKnow,

which became a finalist at

the Amazon Mobile Security

Hackathon. The following

summer, Spaulding worked

as a research assistant for

Walt Disney Imagineering.

“I was doing artificial intelligence

research for tools

that might eventually see use

in the parks,” he said.

When Spaulding is not

IMAGE COURTESY OF SAM SPAULDING

working on robots, he may

be found reading, playing

video games, or enjoying

the outdoors. As a trivia

enthusiast, he is also on Yale’s Quiz Bowl Team. “I like to keep my

skills sharp with bar trivia, go out and play on a team there,” said

Spaulding. “It’s a lot of fun.” And it pays off: he placed second in

the Jeopardy! College Championship.

Given his wide range of experiences, Spaulding had a lot to talk

about when selected to speak at the TedxYale conference this year.

Drawing upon his extensive background with artificial intelligence,

he steered away from the purely technical aspects of his research and

instead explored the unique nature of human intelligence.

Next year, Spaulding plans to continue his education at Massachusetts

Institute of Technology (MIT). Indeed, with all that he

has achieved in the past four years, Spaulding will certainly have a

busy and rewarding post-Yale career ahead of him. “I’ll be going to

graduate school at MIT for robotics, so hopefully I’ll have a lot of

opportunities there,” he said. “I’ve got some ideas for things that

I’d like to work on.”


TRIVIA

FEATURE

1

City Folk Are Hotter than Country Dwellers

Go to Google Earth. Now find a city. Notice that the landscape

appears gray, not green. Lacking vegetation and coated

in asphalt and concrete, a typical city is strikingly different from the

surrounding country. This seemingly innocuous observation has some

pretty intriguing ramifications. In fact, it causes a phenomenon known to

climatologists as the urban island heat effect, whereby dense cities have

been empirically found to be up to twenty degrees Fahrenheit warmer

than their surrounding hinterlands.

According to climatologists at NASA’s Goddard Space Flight Center

who have used satellite thermometry to measure the temperature gradients

emanating from cities, this heat effect is caused primarily by two

factors. First, cities lack plants that absorb solar energy without heating

up via photosynthetic and evaporative processes. Consdiering that cities

are also filled with dark asphalt roads that readily absorb light and heat up,

it is little wonder that cities are hotter than the surrounding countryside.

2

Cities Can (And Do) Get Drug Tested

Remember when your high school biology teacher told you to

think of the excretory system as a city’s sewers? The metaphor

was not too far off. Very much like our own urine, wastewater from the

sewers can tell scientists a lot about the city that produces it, including

which drugs are popular.

In a recent study, epidemiologist

Kevin Thomas

tested the wastewater of

Oslo’s underground sewers

once every other week,

searching for chemicals

indicative of drug use.

These chemicals, known as

biomarkers, are the digestive

products of common

recreational drugs such as cocaine and ecstasy. Their concentration can

be measured to determine the consumption profiles for cities, using

methods analogous to individual drug-tests. For instance, Thomas measured

the concentration of benzoylecgonine, a biomarker of cocaine

digestion, and plotted its concentration over time. Not only did he

discover that Norwegians party exceptionally hard around New Year’s,

but he also found that the official police numbers underestimated the

prevalence of these drugs on the streets of Oslo. Similar tests in Oregon

have also proven successful, providing law enforcement agencies with

one more tool in the fight against illegal drugs.

3

Cities Can Be Modeled as Large Animals

Think of the largest living thing that you know exists. An

elephant or blue whale, perhaps? Try New York City. According


Five Things You Didn’t Know

About Cities

By John Urwin

Although the world is rapidly becoming increasingly urbanized, many facts about

cities still surprise us. Here are five fascinating insights into the nature of the

modern city.

IMAGE COURTESY OF EAWAT

Researchers perform drug tests on

cities by analyzing the microscopic

contents of sewer water.

to British physicist Geoffrey West, cities are just as alive as any human

being, and because of this, they must abide by the same rules that govern

all living things — most prominently, scaling laws. First proposed in his

controversial 2004 paper, these laws quantitatively describe the relationship

between an organism’s size and various other physical properties.

For instance, he noted that size was sub-linearly related to metabolic

need. In other words, an elephant, which weighs 10,000 times more

than a mouse, does not require 10,000 times a mouse’s energy; it actually

only needs 1,000 times as much. In cities, this economy of scale is

also apparent when indicators of urban “metabolism,” such as miles

of road or number of gas stations, are plotted against total population.

By extending this logic, he has deduced numerous formulas that relate

everything from traffic volume to crime rates and average income. Most

surprising of all, his equations work — fairly well, at least.

4

Cities Sink

Atlantis mythology aside, this is actually a growing problem.

While lackluster engineering has slowly (very, very slowly)

doomed particularly heavy historical monuments like the Colosseum,

which sinks seven inches every millennium, the more serious problem

deals with rising water levels. According to recent satellite data, the

global sea level is rising about 3.3 millimeters per year. While this may

seem small, given enough time, certain cities will become submerged

under water. We have already seen it happen (haven’t heard much from

Lohachara anymore, have you?), and with rising tides, small city-states

are beginning to worry. In fact, the situation is getting so dire that the

government of Kiribati, a small island nation in the South Pacific, has

considered relocating.

5

Subways Resemble Slime Molds

In a recent study, Japanese scientists plated bacterial slime

molds on gels that had food sources proportional to the population

of major cities.

They discovered that

the mold, equipped

with neither a brain

nor organs of any

kind, created a network

that resembled

the painstakingly

calculated Japanese

rail-system layout.

Biologically, this phenomenon

is a beautiful

demonstration of

IMAGE COURTESY OF POPULAR SCIENCE

The patterns formed by bacterial slime

mold mirrored subway system structures.

the efficiency of life. From an engineering standpoint, these molds may

help future civil engineers help you avoid rush hour.

BACKGROUND IMAGES COURTESY OF URBAN TIMES AND WIRED


FEATURE

BOOK REVIEWS

Eaarth: Making a Life on a Tough New Planet

BY ALEX CO

At first glance, the misspelling of our planet’s name may cause a double take, but that was author

Bill McKibben’s intention. McKibben emphasizes that the world has become a completely different

place, changing in ways that humans have never seen. In fact, it is so unlike the old Earth that McKibben

believes it deserves a new name, familiar but fundamentally different: “Eaarth.”

Despite the prolonged presence of humans on the planet, McKibben argues that Eaarth has come

to fruition only within the last 50 years of intense development. In this time, carbon dioxide emissions

have increased exponentially. As this trend continues, Eaarth is on a destructive path to serious

environmental damage: atmospheric emission levels have already reached 392 parts per million (ppm),

well above the 350 ppm threshold that experts deem unsafe. The emissions trend will only persist as

modern society continues to develop.

McKibben’s use of statistics and vivid imagery of intense ecological disasters makes his argument

both credible and alarming. To solve our problem, McKibben proposes a grassroots approach. In place

of large-scale development which adds to existing dangers, we must scale back and repair our planet

while adapting to the new planet “Eaarth.” “Maturity is not the opposite of hope,” he writes. “It’s what

makes hope possible.”

Although this type of change is necessary for the planet, McKibben’s plan is slightly unrealistic. Most

likely, few will adopt the “graceful” change that McKibben prescribes. It remains to be seen whether

the people of Eaarth will mature, accept responsibility, and take action.

Rating: &&&&&

BACKGROUND IMAGE COURTESY OF RONEPPINGER.COM

Full Planet, Empty Plates

The Coming Population Crash

BY DEEKSHA DEEP

Rating: &&&&& BY AURORA XU Rating: &&&&&

In his 2012 book Full Planet, Empty Plates, Lester Brown asserts that

our world has reached a tipping point. Already-crowded regions such

as Sub-Saharan Africa, India, and China face projected population

booms, edible crops are being wasted on a dubious biofuel industry,

and global warming is taking its toll on crop yields. All this, according

to Brown, has created the perfect storm: with growing population

pressures and ever-diminishing resources, humanity is now in the

midst of a geopolitical crisis.

One of Brown’s central arguments

is that our global resources are intertwined

— most prominently, food,

fuel, and water. When 70 percent of

our water is reserved for irrigation

and 32 percent of crops are used

for fuel, a shortage of any major

resource lowers the availability and

affordability of all goods in the

global market. Furthermore, every

one degree Celsius increase in global

temperature causes a corresponding

10 percent decrease in crop yields.

Since our resources are so closely

linked, we are even more vulnerable

to environmental damage: we have put all of our eggs in one basket,

and that basket is in a precarious position.

As he cites dire statistics to develop his argument, Brown’s heavy

reliance on numerical elements in prose format can often distract

from the book’s key takeaway. But even in the absence of charts and

graphs, these statistics still have an impact on the invested reader.

Depicting a threat of global proportions, Lester’s message ultimately

prevails because it appeals to the most primitive of instincts: survival.

Although the experts have warned us about a population explosion,

when will the global population actually peak? According to author

and journalist Fred Pearce, it already has — and it is now leveling off

for the first time in several hundred years. In his 2010 book The Coming

Population Crash, Pearce explores the social and economic repercussions

of this surprising global demographic shift.

Pearce sets the stage with a historical narrative of the past two hundred

years, taking the reader from initial fears of unsustainable population

growth to government-enforced

sterilization and abortion programs.

Pearce explains that our generation’s

drop in fertility rates has created lasting

impacts that could extend far into the

future. Within the next few decades,

for example, migration will increase as

a result of rising demand for foreign

hands in Europe and East Asia.

In discussing the history of population

control and the consequences of

the impending population crash, the

book tackles a variety of controversial

subjects that range from government

policy to gender roles. Pearce backs up

each claim with compelling statistics, seamlessly integrating information

from interviews and press reports. In highlighting specific historical

events, he offers an interesting interpretation of human culture.

The Coming Population Crash presents not only a comprehensive overview

of historical efforts to control population growth but also provides

an interesting forecast for the future: as the population ages, society will

succumb to a calmer and wiser influence. The earth may have a more

optimistic outlook than doomsday-forecasters care to admit.


CARTOON

FEATURE

Face-to-Face

BY SPENCER KATZ

About the Artist: Spencer Katz has been a staff cartoonist for the Yale Scientific since he published his first cartoon, “CSI:

Body Unit,” in Fall 2011. Spencer will be graduating from Yale College this May.



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