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August 1997
The Machinery of Thought
Tim Beardsley, staff writer
Using new brain-scanning technologies, researchers have identified the prefrontal cortex as the seat of "working memory"--the place that holds mental representations of the people, things and places on which thoughts are focused.Lightning Between Earth and Space
Stephen B. Mende, Davis D. Sentman and Eugene M. Wescott
Once dismissed as figments of pilots' imaginations, strange flashes appearing above thunderstorms have been confirmed as entirely new forms of lightning. Known as sprites, elves, blue jets and gamma-ray events, these high-altitude phenomena arise through a physics all their own.July 1997
Gamma-Ray Bursts
Gerald J. Fishman and Dieter H. Hartmann
Several times a day, from random points in the sky, intense bursts of gamma rays bombard the earth. Within mere minutes or hours, the sources of this radiation may be releasing more energy than our sun ever will. Breakthrough observations made over the past months are finally helping to explain the astronomical catastrophes behind this phenomenon.Taking Computers to Task
W. Wayt Gibbs, staff writer
Will new 3-D interfaces, speech recognition and other highly touted computer technologies do anything to make workers more productive? A no-nonsense look at the value of new computer features, from the overhyped to the overlooked.June 1997
Configurable Computing
John Villasenor and William H. Mangione-Smith
Seeking the best balance between versatility, speed and cost, computer designers have come up with microchips that can modify their own hardwired circuits as they run. In effect, these new machines rewire themselves on the fly to recognize patterns, search databases or decrypt messages quickly.Panoramas of the Seafloor
Lincoln F. Pratson and William F. Haxby
Seven tenths of the earth's surface is covered with water--what's down there? A new breed of computer-equipped cartographers is finding out. With measurements from the newest generation of sonar-equipped ships outfitted with multibeam sonar, scientists are mapping the depths of the U.S. continental margins in exquisite detail.
May 1997
The Coming Climate
Ian Thomas R. Karl, Neville Nicholls and Jonathan Gregory
Climatologists have concluded that because of the greenhouse effect and other influences, the world will grow a few degrees warmer in the next century. Yet simplistic predictions that scorching summers, more cyclones and heavier rainfall will therefore follow can be far off the mark. These experts offer a more realistic view.New Chemical Tools to Create Plastics
John A. Ewen
For manufacturing or inventing novel plastics, industrial chemists have been at the mercy of the available chemical tools. Now a new category of catalysts, called metallocenes, has come to their rescue. These molecular machines allow more effective control over the growth of polymer chains.
April 1997
Extremophiles
Michael T. Madigan and Barry L. Marrs
Biologists have uncovered a zoo's worth of microorganisms that thrive in places that are hellishly hot, cold, acidic, basic or salty. These "extremophiles" are armed with enzymes that protect them from damage--and that are proving useful in a variety of industrial settings.Jules Verne, Misunderstood Visionary
Arthur B. Evans and Ron Miller
With his tales of submarines, spacecraft, airships and other technological wonders, Jules Verne inspired generations of scientists and enthralled the masses with a bright view of the future. Yet he also harbored a deep pessimism about the potentially oppressive effects of science on society.
March 1997
Special Report: The Internet: Bringing Order from Chaos
Bruno Oudet, Mark Stefik , Clifford Lynch , Paul Resnick, T. V. Raman, Michael Lesk , Marti A. Hearst , Brewster Kahle
For the Internet to reach its maximum potential as a tool for communication and commerce, it must become better suited for useful work. That means making digital databases more encyclopedic but also more orderly. Information providers may also need to transcend the page metaphor that dominates today's interfaces. In this special report, experts describe how a variety of technological and procedural solutions could finally make on-line information easier to locate, more comprehensive, more secure and universally accessible.
February 1997
Animal Research Is Wasteful and Misleading
Neal D. Barnard and Stephen R. Kaufman
Animal Research Is Vital to Medicine
Jack H. Botting and Adrian R. Morrison
Trends in Animal Research
Madhusree Mukerjee
The ways in which scientists experiment on animals - and the question of whether they should do so at all - have been hotly controversial for decades, inside and outside the laboratory. An animal-loving public despises inhumane abuses of creatures, yet it also values the biomedical progress that results. Researchers defend animal experimentation as a necessary evil but can also be personally troubled by the suffering they cause, These articles crystallize some of the arguments voiced on both sides and look at the forces driving change in animal experimentation.Satellite Radar Interferometry
Didier Massonnet
Sometimes the first hint of an impending earthquake or volcanic eruption is a minute shift of the earth's crust. Surveying wide areas for such tiny changes is nearly impossible. But with advanced radar, geolgists can now measure ground motions from space.The Lesser Known Edison
Neil Baldwin
Thomas Edison--born 150 years ago this month--is best remembered for the electric lightbulb, the phonograph and the movie camera. Yet most of his creative energy went into 1,000 other intriguing inventions, including the electric pen, magnetic mining equipment and the poured-concrete house.
January 1997
Tackling Turbulence with Supercomputers
Parviz Moin and John Kim
Predicting the swirling motions of air, water and other ·uids just may be the most staggeringly difficult problem in classical physics. Wind tunnels used to be an engineer's best tool for simulating turbulence. Now supercomputers fill the bill: in many cases, such as estimating the stresses on future hypersonic aircraft designs, computers can do what wind tunnels never could. Yet the complexities of slow still dwarf even the most powerful machines.Cosmic Rays at the Energy Frontier
James W. Cronin, Thomas K. Gaisser and Simon P. Swordy
Imagine a screamingly fast-moving atom fragment that packs all the concentrated wallop of a hard-thrown rock. Astrophysicists can still only speculate about the cataclysms that create such cosmic rays, but they have solid clues.
December 1996
Primordial Deuterium and the Big Bang
Craig J. Hogan
All atoms of deuterium, a heavy isotope of hydrogen, are cosmic leftovers from the first minutes of creation. Knowing how much of this material existed originally can guide astrophysicists in their quest for understanding of early conditions in the universe, which influenced galaxy formation and other later events. Recently they have found a way to peek back billions of years by examining the spectral lines in light from quasars that has passed through ancient interstellar clouds.The Specter of Biological Weapons
Leonard A. Cole
Because of their low cost and horrifying potential for harm, biological weapons could become the arms of choice for many nations and terrorists. The author of a new book on this menace describes what steps can and should be taken to discourage their proliferation.
November 1996
Global Climatic Change on Mars
Jeffrey S. Kargel and Robert G. Strom
Cold, dry and laced with carbon dioxide snow, Mars today is a desiccated world. Yet many times throughout its history, warm spells, volcanoes or meteorite impacts have abruptly thawed water frozen below ground. Catastrophic floods of carbonated water then carved valleys, triggered mud slides and perhaps even formed an ocean. These astrogeologist authors describe how climate on the red planet has changed and what the upcoming missions to Mars will try to learn.The Case for Electric Vehicles
Daniel Sperling
Cars that rely on electricity, not burning fuel, for motive power may offer the only workable solution to the joint predicaments of a global greenhouse effect and severe air pollution in cities. Much of the technology needed for building effective electric vehicles exists now or is under development.
October 1996
Microbes Deep inside the Earth
James K. Fredrickson and Tullis C. Onstott
Biologists once viewed our planet as an ecosystem wrapped around an essentially sterile globe. But drilling has now proved that microorganisms can live thousands of meters beneath the surface. Their existence offers clues about where life might also lurk on Mars and other worlds.Controlling Computers with Neural Signals
Hugh S. Lusted and R. Benjamin Knapp
Neural links have not yet replaced the computer keyboard, but engineers have devised ways to send commands with muscle impulses, eye movements and brain waves. These new methods could benefit everyone, especially the physically impaired.
September 1996
What Causes Cancer?
Dimitrios Trichopoulos, Frederick P. Li and David J. Hunter
Should Women in Their 40s Have Mammograms?
Gina Maranto
Does Screening for Prostate Cancer Make Sense?
Gerald E. Hanks and Peter T. Scardino
Twelve Major Cancers
Scientific Americanstaff
August 1996
Smart Cards
Carol H. Fancher
Unlike ordinary magnetic-stripe cards, these disposable, credit-card-size computers can act as "electronic wallets" for making purchases, holding medical records or even routing telephone calls. After proving themselves in Europe, they may finally be poised to win wider acceptance.Ring Bubbles of Dolphins
Ken Marten, Karim Shariff, Suchi Psarakos and Don J. White
For the benefit of humans, dolphins will play with a tossed ball. But left to their own devices, they instead make novel toys out of air. Through their mastery of fluid dynamics, dolphins can blow bubbles shaped like rings and corkscrews.Trends in Medicine: Gaining on Fat
W. Wayt Gibbs
Obesity plagues the industrial world. Don't blame sloth or gluttony--as researchers have discovered, weight problems are often rooted in genetics and physiology. Dieting does not usually work, but new treatments and prevention might.
July 1996
Who Owns Digital Works?
Ann Okerson
In the age of the Internet, readers and librarians want liberal access to information on-line; authors and publishers want control over how their intellectual property is distributed. New laws have been proposed to strike a compromise, but some would-be solutions make matters worse.The Nature of Space and Time
Stephen W. Hawking and Roger Penrose
In this annotated excerpt from their new book, two of the best known and most brilliant theoretical physicists debate some of the more provocative mysteries confronting science. When things disappear down a black hole, is all trace of them truly lost forever? How did the universe begin, and how will it end? Do the two central theories of modern physics--general relativity and quantum mechanics--conflict, and if so, how can they be reconciled?
June 1996
Trends in Space Science: Science in the Sky
Tim Beardsley
The $27-billion International Space Station will not do many of the jobs once conceived for it. Industrial interest in it has ebbed. Uncertainties about Russia's commitment jeopardize its mission. Next year NASA will start building it anyway.Training the Olympic Athlete
Jay T. Kearney
In competitions that push the limits of human performance, victory can hinge on scant centimeters or hundredths of a second. To get the edge they need, modern Olympians and their coaches turn to science and technology. A sports scientist for the U.S. Olympic Committee describes how training programs drawing on physiology, psychology, aerodynamics and other disciplines are boosting the performance of athletes in four events: bicycling, weight lifting, rowing and shooting.
May 1996
The Kuiper Belt
Jane X. Luu and David C. Jewitt
Four years ago the authors spotted an icy, ruddy object a few hundred kilometers wide beyond the orbit of Neptune and enlarged the known disk of our solar system. A belt of similar objects, left over from the formation of the planets, is probably where short-period comets originate.Software for Reliable Networks
Kenneth P. Birman and Robbert van Renesse
The failure of a single program on a single computer can sometimes crash a network of intercommunicating machines, causing havoc for stock exchanges, telephone systems, air-traffic control and other operations. Two software designers explain what can be done to make networks more robust.
April 1996
Confronting the Nuclear Legacy; Ten Years of the Chornobyl Era
Yuri M. Shcherbak
A decade ago reactor number 4 at the Chornobyl nuclear power plant exploded, showering much of eastern Europe with radioactive debris. The Ukrainian ambassador to the U.S., who was a medical researcher in Kiev and one of the first physicians to treat the wounded, looks at the medical aftermath of the accident. He also contemplates what additional technological and political measures need to be taken to contain the lasting danger. First in a series.Smart Rooms
Alex P. Pentland
The computer on your desk may soon become part of the walls of your office, the furniture in your home and the clothes on your back. Systems that can track people, recognize their faces, and interpret speech, expressions and gestures have become a reality. Using this technology, researchers are building "smart rooms" in which, free from wires and keyboards, people can browse multimedia displays, play with virtual animals or control programs by sign language.
January 1996
The Real Threat of Nuclear Smuggling
Phil Williams and Paul N. Woessner
The amount of plutonium needed to build a nuclear weapon could fit inside two soft drink cans. Much less is needed for other deadly acts of terrorism. Those facts, coupled with the huge, poorly supervised nuclear stockpiles in Russia and elsewhere, make the danger of a black market in radioactive materials all too real. Yet disturbingly little is being done to contain this menace.