scientific american - 2003 07 - smart antennas

... Galactic COPYRIGHT 2003 SCIENTIFIC AMERICAN, INC. Odd Couple They are the most efficient engines of de- struction known to humanity. Their in- tense gravity is a one-way ticket to obliv- ion for anything ... interspersed with liquid-crystal “droplets” whose optical response can be controlled by ap- plying a voltage. The fabrication be- gins with a soup of mon- omer molecules and liq- uid-...

Ngày tải lên: 12/05/2014, 16:18

... Baltimore, is co-sponsoring a meeting on the resolution this Novem- ber. Kurt L. Schmoke, the mayor of Bal- timore, who has supported harm-reduc- tion policies, has pledged to sign the res- olution ... been the signiÞcance of the information con- cept to molecular evolution and its tech- nological applications. Copyright 1993 Scientific American, Inc. SCIENTIFIC AMERICAN July 1993 43 V...

Ngày tải lên: 12/05/2014, 14:49

... that the worldÕs biggest environ- mental release occurred over decades at a site called Tomsk-7 in central Sibe- ria. Tomsk-7, whose existence was clas- 20 SCIENTIFIC AMERICAN July 1994 Managed Care, ... of the Þeldwork be- cause many of the men have off-site jobs. SCIENTIFIC AMERICAN July 1994 35 Copyright 1994 Scientific American, Inc. years ago. A judicious choice of fast- matur...

Ngày tải lên: 12/05/2014, 14:57

... necessary to compare products. What it often fails to do, how- ever, is to translate data-on-a-screen into the understanding-in-a-head need- ed to make a decision. Ultimately the economics of understanding ... be- fore it could be cost-eÝective for large- scale production, comments John Van- der Sande, a researcher at the Massa- chusetts Institute of Technology and co-founder of American Su...

Ngày tải lên: 12/05/2014, 15:01

... (212) 98 0-8 175 or call (800) 77 7-0 444. Scientific American- branded products avail- able. For free catalogue, write Scientific Ameri- can Selections, P.O. Box 11314, Des Moines, IA 5034 0-1 314, or ... trapped in amber yield 25-million-year-old DNA Copyright 1996 Scientific American, Inc. L ast October a jury in Reno, Nev., ordered Dow Chemical Com- pany to pay Charlotte and Mar...

Ngày tải lên: 12/05/2014, 15:07

... 77 7-0 444. Scientific American- branded products avail- able. For free catalogue, write Scientific American Selections, P.O. Box 11314, Des Moines, IA 5034 0-1 314, or call (800) 77 7- 0444. E-mail: info@sciam.com Photocopying ... point out, com- puters are not the only medium com- peting to grab American eyeballs. Peo- ple are also subscribing to more pay-TV on cable stations, tun...

Ngày tải lên: 12/05/2014, 15:10

... 77 7-0 444. Scientific American- branded products available. For free catalogue, write Scientific American Selec- tions, P.O. Box 11314, Des Moines, IA 5034 0-1 314, or call (800) 77 7-0 444. E-mail: info@sciam.com Photocopying ... GRACE Copyright 1997 Scientific American, Inc. A surge of 164 billion cubic me- ters of water bursts through the 100-meter-high walls of a dam, emptyin...

Ngày tải lên: 12/05/2014, 15:28

... ulcer- causing bacterium Heli- cobacter pylori (left) in 62 percent of the peo- ple they tested with heart disease. In com- parison, H. pylori affect- ed only 40 percent of matched control sub- jects. ... science in- struments: the Imager for Mars Path- finder, the Alpha Proton X-Ray Spec- trometer and the Atmospheric Struc- ture Instrument/Meteorology Package. The rover itself also acted as a...

Ngày tải lên: 12/05/2014, 15:38

... into women-belong-back-in-the-kitchen ar- guments. And popular how-to books such as Men Are from Mars, Women Are from Venus, with their tenuous ties to evolutionary biology and their over- simplifications ... down- loading music from the Internet in the May issue. News and Analysis Scientific American July 1999 41 CYBER VIEW On-Line U. DAVID SUTER Copyright 1999 Scientific American, Inc...

Ngày tải lên: 12/05/2014, 15:58

... captured by the FBI in 1995 af- ter a two-year chase that yielded front-page headlines and a six-fig- ure advance for the journalists who made him an icon of mod- ern techno-legend. But for now, he ... act as molecular glue, attach- ing themselves to the amino groups in tissue proteins and cross-link- ing them into hard yel- low-brown compounds known as advanced glyca- tion end products, or A...

Ngày tải lên: 12/05/2014, 16:03