scientific american - 1994 06 - was there a race to the moon

... along the au- ditory pathway to the thalamus, the cortex and the amygdala, arousing a memory that leads to a higher heart rate and the cessation of movement. Atmospheric turbulence hampers earthbound ... computers.Ó On the other hand, Weil doubts wheth- er any human can ever again have a grasp of all of mathematics. One prob- lem, he says, may be that there are too man...

Ngày tải lên: 12/05/2014, 14:56

... Russia and built a base at Bandar Abbas. The U.S. then assigned two Los AngelesÐclass nuclear-powered attack submarines to patrol and map the area. Roughly a quar- ter of the worldÕs oil passes ... Gulf of Oman, the Med- iterranean, the Arabian Sea and north- ern Indian Ocean, the South China Sea, and PaciÞc waters near the north Asian coast. If successful, their sales cam...

Ngày tải lên: 12/05/2014, 14:57

... genes, which play a role in both familial and nonfamilial cancers, BRCA1 apparently plays no role in nonfamilial breast and Toxic Waste and Race: An Unnatural Association Hazardous-waste sites are too ... The story has it that Douglas-Hamilton was struck by MossÕs remarks about the elephantsÕ behavior and her attention to detail; she agreed to work as his assistant for about a...

Ngày tải lên: 12/05/2014, 14:59

... into the ocean. The circle was whiter and more distinct, where the Gulf Stream runs parallel to the American coast, and gradually grew fainter as it passed along the Banks of Newfoundland, to the ... mutations in the character of na- tions, there are still some features that are common to the same people at all times, and which it would therefore be reasonable to...

Ngày tải lên: 17/02/2014, 09:20

... nanometers apart, at the mouth of a channel down which the DNA was to travel. The posts snagged the ball of DNA, and the pres- sure of the molecule against the posts caused it to un- ravel and ... radiation into gravi- tational radiation, and vice versa, with near perfect efficiency. Such a feat sounds as amaz- ing as transmuting lead into gold —and about as plausible....

Ngày tải lên: 12/05/2014, 16:12

... environmental deg- radation and women.) The changes in the text and the late appearance of the subject made for great drama. Government leaders and the media discussed the fact that the planet gains ... class of active galaxy consists of the quasistellar radio sources, or qua- sars, so named because of their starlike appearance. Unlike radio galaxies, qua- sars in no way resem...

Ngày tải lên: 12/05/2014, 14:49

... can lead over several days to death by liver failure. Four neurotoxins have been studied in detail. Of these, anatoxin -a and ana- toxin -a( s) seem unique to cyanobacte- ria. The other twoÑsaxitoxin ... dike at the landward boundary of a salt marsh can prevent the inland migration of the marsh when the sea 68 SCIENTIFIC AMERICAN January 1994 BOTTOMLAND HARDWOOD WETLAND...

Ngày tải lên: 12/05/2014, 14:50

... with the newest aircraft types: the F-117 Stealth Þght- ers, F-15s and F-16sÑAmericaÕs top-of- the- line ÞghtersÑand the sturdy A- 10 ground-attack airplane. Marine and navy aviation units will augment ... in Central Europe oÝer a guide to appro- priate American tank strength. Ger- many deploys almost 4,000 top-of -the- line tanks, which are as good or better than the Þnest...

Ngày tải lên: 12/05/2014, 14:50

... RESEARCH Copyright 1994 Scientific American, Inc. 32 SCIENTIFIC AMERICAN March 1994 C lad in a dark, classically tailored suit and black shoes, Subrahman- yan Chandrasekhar approaches with a slow but ßuid gait. ... plates as they ßoat on the mantle? To Þnd out, the author and his co-workers spent many days deep in the Atlantic on board the Nautile and many more weeks...

Ngày tải lên: 12/05/2014, 14:54

... words, the nuclear wea- pons remain nonlethal. The chairman of the con- ference was John B. Alexan- der, who heads the nonle- thal defense program at Los Alamos National Laboratory and has been called ... lattice. The distortion pattern, called a superlattice, can be seen by x-ray dif- fraction: the ions scatter x-rays onto photographic Þlm, displaying a charac- teristic pat...

Ngày tải lên: 12/05/2014, 14:54