the scientific american book club

Ngày tải lên: 12/05/2014, 16:40

Ngày tải lên: 31/05/2014, 01:31

... these nieces which made them nearly explode with laughter when their mothers read them aloud. All the funny sights in Venice were described, and the stories about the children in India made the ... an umbrella. They called themselves "Knights of the Umbrella and Bundle." The Thoreaus were rather a prominent family in Concord. There were six of them, all told. The father, Mr. John ... needed money and decided to make the colonists pay a tax on tea and a few other things. Then the American colonists were as angry as they could be. They tipped the whole cargo of tea into Boston Harbor,...

Ngày tải lên: 18/02/2014, 08:20

... knowledge of the location and altitude at which the device is explod - ed, and the local meteorology—particu - larly a three-dimensional characteriza - tion of the wind field in the vicinity of the ... when the fireball from the explosion cools sufficiently to lose buoyancy. HOOD was the largest atmospheric test conducted at the Nevada Test Site (and in the continental U.S.). Fortunately, the ... California, at the same time, the corresponding values would have been 0.003, 0.01, and 0.0004 Gy. (A link to these data is available in the bibliography.) Following the publication of the NCI findings...

Ngày tải lên: 15/03/2014, 01:20

... the book you’re reading. So where’s the confusion? The book was about a writer in his fifties working on a book. In the future the book has yet to be written, even if it was written in the ... what they did they were a part of history: they belonged to the United States government. But now they were sitting on the throne of God, the only being higher than the president of the United ... something that was the beginning of the end of the world. Throughout my life I often felt like I was living in a shell of the better past. The sixties, the Beat Generation, the Lost Generation,...

Ngày tải lên: 15/03/2014, 06:20

... presence of their dog in the judging ring. There is no rule of this Club or the American Kennel Club that requires a judge to wait for an owner or handler to bring his dog into the ring. 3. ... During the hours of judging exhibitors are to be on call and have their dogs ready to bring into the judging ring promptly. 2. The owner of the dog or the handler is responsible for the presence ... multiple dogs of the same breed benched together in the breed benching areas must have completed the benching form provided in the premium list and either forwarded with the entries or as...

Ngày tải lên: 23/03/2014, 04:20

... ones. Determining the relative ages of the halo and disk reveals much about the sequence of the formation of the gal- axy. On the other hand, it leaves open the question of how old the entire gal- axy ... tissue, the antibody blocked the attachment of the lymphocytes to high endothelial venules SCIENTIFIC AMERICAN January 1993 87 cells. The L-selectins, or homing receptors, on lymphocytes determine the ... has attached to the endothelium, it can migrate out of the blood vessel. Copyright 1992 Scientific American, Inc. 66 SCIENTIFIC AMERICAN January 1993 The corals lose algae, leaving their tis- sues so...

Ngày tải lên: 12/05/2014, 14:48

... determine the tension in the spring. The tension, in turn, equals the sum of the two forces acting on the weight: the gravitational force and the centrifugal force. To measure either one of these ... gravitational ịeld of the black hole (that is, the rays were straight), the lamp would disappear behind the left part of the tube, and Alice would conclude that the tube was bent to the left. If the light ... change the orientation of their spaceships as they orbit the black hole; both pilots must rotate their spacecraft so that the stretched spring always points toward a mark on the hull. The direction...

Ngày tải lên: 12/05/2014, 14:49

... microkelvins. In the process the coldest atoms mi- grate to the center of the trap, whereas the hotter atoms oscillate from one side to the other. The hot atoms at the sides of the trap can be ... ). They drop their colors and sneak into another maleÕs nest, inseminating the eggs present there. a b c d Copyright 1993 Scientific American, Inc. the metal. The strong electric ịeld at the ... survival, they may suÝer longer from the nonfatal but highly disabling illnesses associated with old age. SCIENTIFIC AMERICAN April 1993 51 Copyright 1993 Scientific American, Inc. 82 SCIENTIFIC AMERICAN...

Ngày tải lên: 12/05/2014, 14:49

... demon- strated in the laboratory. The EPR phenomenon is the linchpin of quantum teleportation. Alice takes one of the EPR photons and gives the other to Bob. Bob then moves to an- other location with the photon. ... Furthermore, if the hot end of the rod is then plunged into ice, a wave of cooling will follow the wave of heat down the length of the metal. In the same way, temperature òuctua- tions at the ... throughout the length of the cilium. In addition, an extra pair of mi- crotubules not found in the centriole develops along the axis. The structure of the axoneme mirrors the ninefold symmetry of the...

Ngày tải lên: 12/05/2014, 14:49

... response to the an- tigen; soon their clones make up most of the population in the centers. While they are proliferating, the B cells also diÝerentiate and mutate. They modify the DNA in their gene ... SSC. Like other colleagues at the laboratory, Bill entered the ịeld to unravel the great mysteries of physics, among them the question of why all the fundamental particles have the masses they do. ... the House voted to halt the SSC, the Senate rescued the laboratory. The fate of the collider now rests on the ability of the Senate to pull oÝ the same feat this year. The SenateÕs chief SSC advo- cate,...

Ngày tải lên: 12/05/2014, 14:50

... between these two particles de- pends on the way they approach each other. If the ịrst moves up directly be- neath the second, then the positively charged top of the ịrst is closest to the negatively ... to the forces at- tracting or repelling them. At the same time, no matter in which direction the particles are headed, their poles point either up or down toward the elec- trodes. Together these ... closer to forcing the particles side by side. If the chains tilt too far, the particles slip out of the zone in which they mutually attract, the chains break and the material òows. The amount of stress...

Ngày tải lên: 12/05/2014, 14:50

... ÒDonahue.Ó Then, recalling the way he comforted the pregnant graduate student, I think, Why not? ÑJohn Horgan 38 SCIENTIFIC AMERICAN November 1993 Copyright 1993 Scientific American, Inc. SCIENTIFIC AMERICAN ... and 60B SCIENTIFIC AMERICAN November 1993 Copyright 1993 Scientific American, Inc. there is another explanation as well. In 1982 my colleague Thierry Heid- mann and I further proposed that the ability ... better oÝ having their own symphony orchestras and other cultural oÝerings, they should also keep their vital industries local. Copyright 1993 Scientific American, Inc. 74 SCIENTIFIC AMERICAN November...

Ngày tải lên: 12/05/2014, 14:50

... im- Copyright 1994 Scientific American, Inc.Copyright 1994 Scientific American, Inc.Copyright 1994 Scientific American, Inc.Copyright 1994 Scientific American, Inc. 32 SCIENTIFIC AMERICAN March ... occurs, the unchanged seg- ments of the cloned gene, together with the neo r gene sandwiched between them, replace the target sequence in the chromosome. But the tk gene, lying outside the zone ... measure of the perfor- mance of a bipolar transistor is the manner in which the gain of the tran- sistor (the ratio of the current switched by the transistor to the current needed to turn the transistor...

Ngày tải lên: 12/05/2014, 14:54

... oÛce. The scrawny little specimens scurrying across the surface of the spongelike nest are the workers; the soldiers lurk within. Wilson pulls a plug from the top of the nest and blows into the ... lauded The Diversity of Life as Òa 38 SCIENTIFIC AMERICAN April 1994 Copyright 1994 Scientific American, Inc.Copyright 1994 Scientific American, Inc. more lethal diseases do, even though they ... from the uterine lin- ing proliferates in other areas of the body, such as the bladder, intestine or, in rare cases, the lung. How these cells reach the distant organs remains un- known. One theory...

Ngày tải lên: 12/05/2014, 14:54

... that Òdepending upon their view of the Apollo timetable, the Soviets may feel that there is some prospect of their getting to the moon ịrst, and they may press their program in the hopes of be- ing ... by then they knew that the U.S. intended to send humans into orbit around the moon later that month. This launch presented the Sovi- ets with perhaps their ịnal opportuni- ty to beat the Americans ... American presence on the moon, the U.S. lunar program also soon wound down. The sixth and last Apollo landing mission left the moon in December 1972. By then the lunar eÝort had clearly met the...

Ngày tải lên: 12/05/2014, 14:56

... accretion of the earth culminated in the diÝerentia- tion of the planet: the creation of the core the source of the earthếs magnet- ic ịeldẹand the beginning of the at- mosphere. In 1953 the classic ... hypoth- eses meet the test of observation and experiment. SCIENTIFIC AMERICAN October 1994 57 FURTHER READING LONELY HEARTS OF THE COSMOS: THE SCIENTIFIC QUEST FOR THE SECRET OF THE UNIVERSE. Dennis ... re- turned the elements to the space be- tween the stars. There gravitation mold- ed them into new stars and planets, and electromagnetism cast them into the chemicals of life. The ink on this page, the...

Ngày tải lên: 12/05/2014, 14:58

Ngày tải lên: 12/05/2014, 14:59

Ngày tải lên: 12/05/2014, 15:01

Ngày tải lên: 12/05/2014, 15:01