scientific american - 2002 10 - vehicle of change - how fuel - cell cars could revolutionize the world

... Carter, the abalone diver and author of The OtherTheory of Physics, proffering a “circlon” the- ory of the universe, wherein all matter is found-ed on hollow, ring-shaped tubes that link every-thing ... S. Warren of Arizona State Uni-versity found that the birds of Phoenix prefer the greenery of well-to-do neighborhoods over that inlower-income areas. Parks of the well-heeled con-tained an ... is driving the increase. Chi-na could have 10 million new infections by the end of this decade, in part because 54 per-cent of the population do not know how the disease spreads. “These regions...

scientific american - 1997 10 - special issue - the future of transportation

... conservation. The hypothesis brings together twofundamental ways of looking at ecosys-tems: who eats what, and how the phys-ical terrain constrains the resident crea-tures. After years of studying ... experiment-ed with the two structures, ﬁrst oncomputer models, then on the real thing. The researchers removed small stretch-es of amino acids from B-1 that con-tributed to the formation of beta-sheetsand ... retains half of the amino acid sequence of B-1 but has the helical structure of Rop. In more recentwork, the team created Janus II, whichcarries 61 percent of the B-1 sequence,meaning that the researchers...

scientific american - 1998 10 - how hackers break in

... occurs, but whether the right- or left-handed form breaksdown depends on the spectrum of the light.) When the ﬁrst life-forms eventu-ally emerged, they used the more numer-ous left-handed amino ... behind the plane of the Milky Way, the gal-axy—named Dwingeloo 1—would beone of the 10 brightest in the sky. Judg-ing from its rate of rotation it has aboutone third the mass of the Milky ... zone of avoidance into one of the most exciting regions in the extra-galactic sky. The mysterious Great At-tractor is now well mapped; the discov-ery of the Sagittarius dwarf has shown how the...

scientific american - 2002 09 - special issue - a matter of time

... Meanwhile the ﬂoorstie the inner frame to the outer one, bracing the entire ediﬁce. In the case of the World Trade Center,which was a state -of- the- art design in the late1960s, the steel-mesh ... remember. The fact thatwe remember the past, rather than the future, is an observa-tion not of the passage of time but of the asymmetry of time.Nothing other than a conscious observer registers the ... homeowners’ estimates of the value of their house in 2000 and their income in 1999. The figures noted on the map apply to the home counties of cities.COPYRIGHT 2002 SCIENTIFIC AMERICAN, INC.WOLFGANG...

scientific american - 1993 10 - is los angeles winning the war on smog

... thatin almost one Þfth of all the vehicles on the road, the emissions-control equip-ment was either removed by the own-er or damaged by the use of leaded fu-els. The latter problem has abated ... incorpo-rated the HS-tk gene, whereas virtuallyno normal cells did. When they thengave the rats ganciclovir, they got an-other pleasant surprise. The drug killednot only the infected tumor cells ... contributes 26 percent of the hydrocarbons, 18 percent of the nitro-gen oxides and 30 percent of the sulfuroxides and smaller percentages of oth-er pollutants. The remainder of the pol-lutants are...

scientific american - 1994 10 - special issue - life in the universe

... understanding of the laws of nature.The present gaps in our knowl-edge of the laws of nature standin the way of explaining the ini-tial conditions of the universe, at 10 Ð12second after the nominal ... spaceand the distribution of matter are inti-mately linked; the observed expansion of the system of galaxies reveals the un-folding of space itself. An essential fea-ture of the theory is that the ... way how the wave function of any system changes with time. Then,quite separate, there is a set of princi-ples that tells how to use the wave func-tion to calculate the probabilities of var-ious...

scientific american - 1995 10 - dangers from new viral plagues

... cor-als in parts of the western Atlantic, the Keys and the Caribbean from the late1970s until the mid-1980s. As with thatmalady, tissue cells begin dying near the base of the corals. Soon the ... special in the eyes of Representa-tive Don E. Young of Alaska. The defend-ers of the ESA ex-pect Young to intro-duce into the Housean authorization billthat would defang it. The legislation ... inner and out-er edge may be 500 times greater than the distance from the earth to the sun. The data gathered so far support the thesis that the Kuiper belt is the source of most short-period comets,...

scientific american - 1996 10 - hell's cells

... blood cells, so thatthere are more of them available to de-stroy the cancerous cells; these whiteblood cells could then be put back in-side the body to reproduce and to battle the tumor. Further ... an idea of how mucin inter-acts with the immune system. Specific-ally, workers used XPS to study the sur-face of the molecule, which let them be-gin figuring out the relation between the molecule’s ... holds li-censes for 75 long-liners, explains that hisfleet targets big-eye tuna in internationalwaters off the southern coast. One ma-jor concern of the NFF is that the licens-ing of some...

scientific american - 1996 12 - traces of the big bang

... because the power and economy of mass-produced processors are oftencited as factors in the collapse of the supercomputing market. Asmuch cheaper and easier-to-use work-stations based on off -the- shelf ... director of the San Diego center. The Tera machine’sprojected peak rate of one gigaﬂop perprocessor is about half that of the CrayT90, a state -of- the- art vector supercom-puter. The T90, however, ... Univer-sity for their discovery of superfluid he-lium 3.Physiology or Medicine. Peter C. Doher-ty of the University of Tennessee and RolfM. Zinkernagel of the University of Zur-ich, for their...

scientific american - 1999 10 - europa's ocean

... part,Wayland says that the emergency per-mits were not the result of Lott’s actionsbut of the needs of cotton farmers.Complicating the issue is the purport-ed efﬁcacy of other products. The EPAlists ... plants them-selves might effect change. Each of the team’s 10 simulations began with the grasslands of 9,000 years ago and endedwith the arid desert of the present. The only external force they ... about—involve the gradual release of energy by the de-bris, which should be largely independ-ent of the characteristics of the late star.Other researchers are less sanguine. The disparities might be the...

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