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The Health bulletin [serial] - University of North Carolina at Chapel Hill

The Health bulletin [serial] - University of North Carolina at Chapel Hill

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16 <strong>The</strong> <strong>Health</strong> Bulletin March 1951<strong>of</strong> diphenhydramine hydrochloride (usedin tre<strong>at</strong>ment <strong>of</strong> allergies) were l<strong>at</strong>erfound to be missing. Tre<strong>at</strong>ment was begtmabout five hours after the supposedingestion. <strong>The</strong> description <strong>of</strong> her conditioncontinued:"<strong>The</strong>re were recvu-rent generalizedconvulsions for about eight hours; theface was flushed, and the pupils weredil<strong>at</strong>ed and nearly fixed. Between seizuresthe child cried out and talked in arambling manner and showed hyperextension<strong>of</strong> the trunk (bowed stiffening<strong>of</strong> the back) and involuntary movements<strong>of</strong> the extremities. <strong>The</strong> next day sheappeared normal."<strong>The</strong> same issue <strong>of</strong> the Journal containsan editorial commenting on newcontrolled studies <strong>of</strong> the use <strong>of</strong> antihistaminesin the tre<strong>at</strong>ment <strong>of</strong> colds.<strong>The</strong>se included Navy male recruits duringtwo influenza episodes.Two antihistaminic drugs used intherapeutic dose "did not prevent thecommon cold or modify the course inthose who developed colds," and showedno superiority over placebos (harmlesspills containing no medic<strong>at</strong>ion), theJournal points out.* * );: ;:=EXPERTS TELL AT WHAT DISTANCEONE SHOULD VIEW TELEVISIONFor eye comfort, how far should aperson be from the screen to view television?Dr. William Blake, <strong>of</strong> Astoria, LongIsland, N. Y., put this question to theJournal <strong>of</strong> the American Medical Associ<strong>at</strong>ion.Because <strong>of</strong> its controversialn<strong>at</strong>ure, the Journal submitted the questionto three "competent medical authorities,"and they all came up withvirtually the same answerAs a general recommend<strong>at</strong>ion forsmall or moder<strong>at</strong>e-sized screens, a distance<strong>of</strong> roughly 10 times the diameter<strong>of</strong> the screen is found most comfortablefor clear viewing and avoidance <strong>of</strong> eyef<strong>at</strong>igue.This, substantially, is the same opinionas th<strong>at</strong> expressed by the American Societyfor the Prevention <strong>of</strong> Blindness.One authority whose answer is printedin the A.M.A. Journal, says "the optimaldistance from which one should w<strong>at</strong>chtelevision varies from one person to another,depending <strong>at</strong> least partly on hisst<strong>at</strong>e <strong>of</strong> refraction and on the size <strong>of</strong>the screen. Placement <strong>of</strong> furniture androom size also influence one's preference.In general, a distance <strong>of</strong> 10 feetor more would be preferable, since thenthere is necessary only a moder<strong>at</strong>eamount <strong>of</strong> convergence and accommod<strong>at</strong>ion.One should avoid sitting closerthan five feet."<strong>The</strong> authority said further th<strong>at</strong> ifeye f<strong>at</strong>igue occurs <strong>at</strong> a distance roughly10 times the diameter <strong>of</strong> the screen ina person with no visual abnormalities,"the distance may be changed.""In fact," he continued, "changing occasionallyfrom one chair to anothershould help in avoidance <strong>of</strong> f<strong>at</strong>igue notonly <strong>of</strong> the sense <strong>of</strong> vision but <strong>of</strong> theneck muscles. Regardless <strong>of</strong> the distance<strong>of</strong> viewing, there seems to be no evidenceth<strong>at</strong> eye f<strong>at</strong>igue in the 'normal'eye will cause p<strong>at</strong>hological changes. <strong>The</strong>chief problem is th<strong>at</strong> <strong>of</strong> comfort."One <strong>of</strong> the other authorities, whoseanswers also were published in theA.M.A. Journal, said th<strong>at</strong> the more defectsthere are in the television picture,"the gre<strong>at</strong>er is the tendency for visualf<strong>at</strong>igue.""This," he said, "includes such defectsas out-<strong>of</strong>-focus pictures, those th<strong>at</strong> aretoo dim, too fl<strong>at</strong> and with too much contrast,and those th<strong>at</strong> weave and jump.<strong>The</strong> viewing distance should thereforenot be near enough for these defects,especially the graininess, to be overlyapparent.. This is more important thansize <strong>of</strong> the picture, although the graininessand size may go together. Furthermore,the appearance <strong>of</strong> graininess willincrease with the increase in brightness<strong>of</strong> the screen. Television should be observedin a lighted room, so th<strong>at</strong> thereis not too gre<strong>at</strong> a contrast between thescreen and the background."<strong>The</strong> third authority said th<strong>at</strong> "whentelevision is viewed from a distanceless than 10 times the diameter <strong>of</strong> thetelevision tube, no harm wh<strong>at</strong>ever isdone to the eyes but the picture losesin quality as the scanning lines thenbecome visible.."

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