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Scientific American January 2004(97s).pdf

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Date Nov 14, 2004

Established 1845
E D I T O R IN CHIEF: John Rennie EXECUTIVE EDITOR: Mariette DiChristina MANAGING EDITOR: Ricki L. Rusting NEWS EDITOR: Philip M. Yam SPECIAL PROJECTS EDITOR: Gary Stix SENIOR E D I T O R : Michelle Press SENIOR WRITER: W. Wayt Gibbs EDITORS: Mark Alpert, Steven Ashley,...

ble when aeroplane ﬂight, at least on a full-sized scale, had never gone beyond the theoretical stage.”...

privacy of health data” laid out in the Health Insurance Portability and Accountability Act of 1996, Patterson says. Although the NIH does not have to comply with the act, it has “for decades protected the privacy of patient data because of other federal regulations,” she adds, noting that many of the participating institutions must comply with the act. In ﬁve years, a broad prototype effort is supposed to be up and running; in another ﬁve, the NIH expects to have in place “the fabric of a national network of networks,” Patterson states. NECTAR is a monumental undertaking, and she does not expect it to be easy. For that reason, she explains, the NIH will involve the institutions that will be part of the network as the plan is developed. That part seems to have gotten off rather slowly; two months after the road map was announced, Masys said he and others in the research and informatics communities were still largely in the dark. But he applauds the NIH for its vision, which he calls “exactly the right thing to do on a national scale.” Patterson promises that NECTAR will soon pick up steam with the issuance of solicitations for pilot projects. Judging from the feedback received already, she believes a “rational and highly communicative” strategy can lead to the forging of the necessary partnerships. “There’s a real hunger out there to have some uniformity and some collaboration among research centers,” she observes. Satisfying that hunger, the NIH hopes, will more quickly transform research ﬁndings into drugs and therapy that people can use. Daniel G. Dupont edits the online news service InsideDefense.com....

learned to optimize their choices, tending to select cards from decks that made them money. But participants with a pain history tended to select cards randomly: they seemed to lack a master plan, which resulted in 40 percent fewer good choices compared with those...

analysis of materials, ﬂuorescence microscopy of single molecules, and telecommunications. They have even been used to look for faults in integrated circuits by observing the infrared light emitted by transistors when they switch. Before the JPL-Caltech device can join the ranks of other single-photon detectors, however, certain problems still remain to be worked out. In particular, noise levels are higher than expected. The detector’s sensitivity “is good enough for some ground-based...

Snoop Tube
Existing detectors for pollutants and chemical and biological agents sense only relatively high particle densities. Although vibrating devices can concentrate aerosols into low-pressure nodes, current designs are hard to align and consume lots of power. Now a pipe made of piezoelectric crystal has shown it can concentrate particles up to 40 times using a mere 0.1 watt, making it suitable for battery-powered, handheld detectors, according to Los Alamos V I B R A T I O N S trap National Laboratory aerosols along three nodes (white dots). scientists. They vibrated tubes several inches wide and long in and out (oscillating the tube’s diameter) to produce an internal standing pressure wave in which particulates could be trapped. The tube generated three narrow streams aligned with the axis, at airflows of up to 250 liters of air per minute, as reported at a November meeting of the Acousti— JR Minkel cal Society of America....

plex sugar molecules—was published in the August 29, 2003, Science. More still needs to be done before GlycoFi can offer a complete industrial platform that will compete with Chinese hamster ovary cells. The yeast must be engineered further to add the sugar sialic acid to a protein. But the possibility of making human proteins in yeast cells looms as a formidable technology. Gerngross notes that fermentation times in yeast may take three days, compared with two to three weeks in hamster cells. And both the amount of protein produced and the uniformity of the product show the promise of the technology. Lowered production costs from these improvements in manufacturing could potentially bring down the cost of biotechnology drugs. “We hope to be able to produce longer-lasting and...

No one talks bunkum with a better vocabulary than those who lace their hokum with scientistic jargon....

Overview/ High-Velocity Clouds
Since the early 1960s astronomers have thought that the Milky Way and other galaxies were born early in cosmic history and then evolved slowly. Today, however, evidence indicates that galaxies are continuing to grow. They cannibalize their smaller brethren and gulp down fresh gas from intergalactic space. ■ In our Milky Way we have a close-up view of the ongoing construction work. The incoming gas takes the form of high-velocity clouds discovered decades ago. Only recently were some of these clouds proved to be fresh material; observationally, they get entangled with circulating gas. ■ These clouds come in several guises: clumps of neutral hydrogen reminiscent of intergalactic gas; a stream of gas torn out of nearby small galaxies; and highly ionized hot gas that may be dispersed throughout the intergalactic vicinity.
■...

Going Out with the Tide
N E I T H E R O O R T ’ S H Y P O T H E S I S nor the fountain model, however, could explain all characteristics of all HVCs. The problem was further complicated by the discovery in the early 1970s of the Magellanic Stream, a ﬁlament of gas that arcs around the galaxy. The stream follows the orbits of the Large and Small Magellanic Clouds, two small companion galaxies that revolve around the Milky Way like moons around a plan-...

ern sky in 2000 [see illustration above]. A third survey, by Dap Hartmann and Butler Burton of Leiden Observatory, became available in 1997 and mapped all of the Milky Way’s neutral hydrogen, including both HVCs and IVCs. A further contribution came from observations in visible light, made by instruments such as the Wisconsin HydrogenAlpha Mapper [see “The Gas between the Stars,” by Ronald J. Reynolds; Scientiﬁc American, January 2002]. Although neutral hydrogen does not shine at visible wavelengths, ionized gas does, and the outer parts of HVCs are ionized by far-ultraviolet light from the Milky Way and other objects. The radiation also heats the clouds’ exteriors to 8,000 kelvins. The amount of visible light is a measure of the intensity of the radiation ﬁeld surrounding the HVC, which in turn depends on its distance from the galactic disk. Thus, these observations offer a rough way to estimate the location of HVCs. The most important progress has come from observations of spectral absorption lines in HVCs. Instead of looking for light given off by the gas, this work analyzes light blocked by the gas—speciﬁc atoms ﬁlter out speciﬁc wavelengths of light. Three observatories have made the largest contributions: the
SCIENTIFIC AMERICAN...