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SCIENCE & TECH COVERAGE
Mercury Influx into Eco-system
may have caused Extinction 250mn
Years Ago
In a new study, scientists have discovered a new culprit
that is likely to have been involved in the Earth’s greatest
extinction event that took place 250 million years ago
when rapid climate change wiped out nearly all marine
species and a majority of those on land.
According to the researchers, an influx of mercury into
the eco-system may have been responsible for the mass
extinction.
About 250 million years ago, a time long before dinosaurs
ruled and when all land formed one big continent, the
majority of life in the ocean and on land was wiped out.
The generally accepted idea is that volcanic eruptions
burned though coal beds, releasing CO2 and other
deadly toxins. Direct proof of this theory was outlined
in a paper that was published by these same authors
last January in Nature Geoscience.
The mercury deposition rates could have been
significantly higher in the late Permian when compared
with today’s human-caused emissions. In some cases,
levels of mercury in the late Permian ocean was similar
to what is found near highly contaminated ponds near
smelters, where the aquatic system is severely damaged,
say researchers.
‘Thin Graphene’s Completely
‘Invisible’ to Water
Graphene, which is the thinnest material known to
science, is not only transparent to eye but also to water,
a new study including Indian origin researcher has
revealed.
Engineering researchers at Rensselaer Polytechnic
Institute and Rice University coated pieces of gold,
copper, and silicon with a single layer of graphene, and
then placed a drop of water on the coated surfaces.
Surprisingly, the layer of graphene proved to have
virtually no impact on the manner in which water spreads
on the surfaces.
The findings could help inform a new generation of
grapheme-based flexible electronic devices.
Additionally, the research suggests a new type of heat
pipe that uses graphene-coated copper to cool computer
chips.
As the researchers increased the number of layers of
graphene, however, it became less transparent to the
water and the contact angles jumped significantly. After
adding six layers of graphene, the water no longer saw
the gold, copper, or silicon and instead behaved as if it
was sitting on graphite.
The study has been published in the journal Nature
Materials.
Mexico Rolls out Super Computer
Mexican scientists inaugurated Latin America’s No. 2
supercomputer by size and speed, with the ability to
process 24.9 trillion operations per second. The
computer, along with others at two major Mexican
universities, is part of the new high-performance network
Lancad.
The Lancad project will generate physical infrastructure
that will improve Mexico’s competitive position in the
world. Besides benefiting the academic sector, the
computer also will benefit the government and
businessmen. The government can accommodate critical
applications that require a high level of storage and
security, or push for education and distance-learning,
while the private sector can develop modeling
applications and simulation of processes or the
development of tools and teams.
Scientists for the First Time
Produced Mixed Embryo Monkeys
Scientists for the first time produced monkeys composed
of cells taken from separate embryos. They combined
cells from different embryos and implanted them into
female monkeys. The cells never fuse, but they stay
together and work together to form tissues and organs.
The animals, which contain genetically distinct groups
of cells from more than one organism, are termed as
chimeras. The three rhesus monkeys born are named
Chimero, Roku and Hex. These monkeys have tissues
made up of a mixture of cells, which represent as many
as six separate embryos.
Although Chimeras are essential for studying embryonic
development, research has largely been restricted to
mice. Initial efforts by the scientists to produce living
monkey chimeras by introducing cultured embryonic
stem cells into monkey embryos failed.
Scientists Produced Artificial
Human Semen to help Infertile Men
Scientists claimed to find a way to produce artificial
human semen that could help infertile men father their
own children. The scientists for the first time grew mouse
sperm in a laboratory. For this, they used few germ cells
in a laboratory dish. These cells produce semen in
testicles.
In fact, the scientists grew the sperm by enveloping the
germ cells in a special compound called agar jelly to
create a similar environment to that found in testicles.
The sperm produced thus were healthy and not
genetically damaged. The findings of the scientists are
published in the latest edition of the Asian Journal of
Andrology.
Scientists found Cells that can help
prevent Spread of Cancer
A team of scientists in the second week of January 2012
identified a group of cancer cells that play a main role in
preventing the development of the disease. This
scientific finding could lead to re-evaluation of common
cancer treatment for patients.
It pointed out that anti-angiogenic therapies that target
those tumour cells- called pericytes- inadvertently make
tumours more aggressive. The study was published in
the journal Cancer Cell. It underscores the need of more
research on tumour-cell composition to bring out more
effective therapies.
For the study, the team of scientists created genetically
modified mice to support drug-induced depletion of
pericytes in growing tumours. They then deleted
pericytes in their cancer tumours, decreasing pericyte
numbers by 60 percent.
Scientists claimed that Alcohol can
be used to treat Tremors
Scientists at the US National Institutes of Health claimed
that alcohol could be used to treat tremors, a brain
disorder that triggers exaggerated shaking and occurs
during movement. The octanol (a form of alcohol and a
colourless ingredient in perfume) can help treat tremor.
The tremor can affect people of all ages.
For their experiment, the scientists gave patients a single
dose of one milligramme of octanol for each kilogramme
of their weight, and found it significantly decreased
tremor for up to 90 minutes. In their second experiment,
people who had octanol had fewer symptoms of tremor
after five hours than those were given a placebo.
Doomed Mars Probe Lands in
Pacific Ocean
Russia’s Defence Ministry said a failed probe designed
to travel to a moon of Mars has crashed, showering
debris over the southern Pacific.
The Ministry said the fragments fell 1,250 kilometres
west of Wellington Island.
The Phobos-Grunt was one of the heaviest and most
toxic space junk ever to crash to Earth, but the risks
posed by its crash were minimal as the probe’s toxic
rocket fuel and most of the craft’s structure were to burn
up in the atmosphere anyway.
The $170-million Phobos-Grunt was Russia’s most
expensive and the most ambitious space mission since
Soviet times. The spacecraft was intended to land on
Phobos, one of Mars’ two moons, collect soil samples
and fly them back to Earth.
Genetically Modified Silkworms
can Spin Stronger Silk than Spiders
Scientists in America claimed to have genetically
modified silkworms to spin the much stronger silk that
spiders produce. Their work could lead to new material
for medicine and engineering. Their eventual aim is to
produce silk from worms that has the toughness of
spider silk. In weight-for-weight terms, spider silk is
stronger than steel. The scientists have been trying to
reproduce such silk for decades.
Australia detected Deadly Disease
Murray Valley Encephalitis
Health authorities in Australia are bracing against a
possible outbreak of a potentially deadly disease, Murray
Valley Encephalitis. The virus is transmitted by
mosquitoes and was recently found in chicken in
Australia’s most populous state, New South Wales.
Encephalitis is an inflammation of the brain, usually
caused by a viral infection. Although rare, it is potentially
life-threatening, and may lead to permanent brain damage
or death. Symptoms may include a high fever and
headache, accompanied by a stiff neck, vomiting, light
sensitivity, and convulsions. It can also infect humans.
China Launched Asia’s Largest
Helicopter
China’s largest-ever civil helicopter got certification from
the civil aviation administration, the country’s civil
aviation authority said. The move marks the official
approval for the 13-tonne AC313, Asia’s largest
helicopter, to enter the market, said the Aviation Industry
Corp of China (AVIC), which developed and
manufactured the helicopter.
The aircraft focuses on designs of maintainability, life
reliability, indemnification and life cycle efficiency, and
meets international safety standards, underlining China’s
abilities in the research and development (R&D) of large
helicopters.
AC313 is also world’s first civil helicopter to receive an
A-category airworthiness certificate at an altitude of
4,500 meters. The aircraft can be deployed for emergency
rescue operations, forest fire prevention, transport,
offshore operations, medical aid, sightseeing and
business trips.
NASA Uncovers Moon’s Darker Side
New maps produced by the Lyman Alpha Mapping
Project (LAMP) aboard NASA’s Lunar Reconnaissance
Orbiter have revealed features of the Moon’s northern
and southern poles in regions that lie in perpetual
darkness. LAMP, developed by the Southwest Research
Institute (SwRI), uses a novel method to peer into these
so-called permanently shadowed regions (PSRs), making
visible the invisible.
Symptoms of Tremor
Tremor occurs during movement, but not at rest. It affects
The computer, dubbed Xiuhcoatl (“serpent of fire”), will not only the arms and hands but also the head, face and
allow the processing of information to solve problem in feet. In at least half of cases there is a family history as The LAMP maps show that many PSRs are darker at
health care, climate change and security, among many well. Other causes of similar tremor symptoms include far-ultraviolet wavelengths and redder than nearby
others. Using the computer a pharmaceutical firm can an over-active thyroid, anti-epileptic medication and surface areas that receive sunlight. They show many
undertake simulations of new medications, aerospace drugs used to treat psychiatric disorders. In fact, tremor permanently shadowed regions (PSRs), are darker at
simulations can be carried out and scientists can work is caused by spontaneous activity in nerve cells in the far-ultraviolet wavelengths (top) and redder than
with new proteins.
areas of the brain that control movement. One theory is nearby surface areas that receive sunlight (bottom).
that alcohol may help dampen this activity. It is known The darker PSR regions are consistent with having
The supercomputer, the largest in the region after a that alcohol has some effect on this kind of movement large surface porosities, indicating “fluffy” soils,
machine in Brazil, required an investment of some 18 because as well as reducing tremor. It can also cause it if while the reddening is consistent with the presence
million pesos ($1.3 million).
drunk excessively.
of water frost on the surface.
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