When Earth Tipped, Life Went Wild
A sudden tilting of the planet during the Cambrian period may have spawned an explosion in the diversity of animal life.
Kirschvink, J.L., R.L. Ripperdan, and D.A. Evans. 1997. Evidence for a large-scale reorganization of early Cambrian continental masses by inertial interchange true polar wander. Science 277(July 25):541.
Images and an animated video are available at the following Caltech website: http://www.gps.caltech.edu/~devans/science.html.
Monastersky, R. 1994. Fossils widen range of biological burst. Science News 145(June 6):372.
______. 1993. Siberian rocks clock biological Big Bang. Science News 144(Sept. 4):148.
______. 1993. Mysteries of the Orient. Discover (April):39.
Internet congestion stirs up data storms
Frequent spikes of high activity occurring at random times and typically lasting a fraction of a second punctuate Internet traffic.
Huberman, B.A., and R.M. Lukose. 1997. Social dilemmas and Internet congestion. Science 277(July 25):535.
Cowen, R. 1997. Postcards from the Red Planet. Science News 152(July 12):20.
Peterson, I. 1996. Circumventing traffic jams on the Internet. Science News 149(March 23):181.
Internet Weather Reports (IWR) and other data on Internet use are available at http://www.mids.org/.
Information about the National Science Foundation's connections program is available at http://vvv.nsf.gov/nsf/press/pr968.htm.
HIV protein prepares virus' next victims
The HIV protein Tat triggers changes within immune cells that allow the AIDS virus to reproduce there.
Li, C.J., et al. 1997. Tat protein induces self-perpetuating permissivity for production of HIV-1 infection. Proceedings of the National Academy of Sciences 94(July 22):8116.
Weak flames ignite hope for clean engines
Studies of flames aboard the space shuttle allow researchers to improve their models of combustion and soot formation.
Smaglik, P. 1997. A new direction for microgravity fires. Science News 151(Feb. 22):119.
Wordy tots ignore some speech sounds
As 14-month-old infants begin to learn word meanings, they ignore certain speech sounds that 8-month-old babies perceive with ease.
Stager, C., and J. Werker. 1997. Infants listen for more phonetic detail in speech perception than in word-learning tasks. Nature 388(July 24):381.
Bower, B. 1997. Everybody's talkin'. Science News 151(May 3):276.
Jellies and their twinkling protein
Individual molecules of a green fluorescent protein, which makes jellyfish glow, blink repeatedly when excited by laser light.
Dickson, R.M., et al. 1997. On/off blinking and switching behaviour of single molecules of green fluorescent protein. Nature 388(July 24):355.
Manning, E. 1997. Glow fish. BioScience 47(March):135.
Pennisi, E. 1994. Jellyfish's glow reveals head's beginnings. Science News 145(June 4):358.
Wu, C. 1997. Bacteria give new meaning to 'computer bug.' Science News 151(March 8):140.
______. 1996. The shape of more colors to come. Science News 150(Oct. 5):210.
Secrets underlie lethal heart condition
Five genetic mutations are now known to cause long QT syndrome, a potentially fatal heart condition.
Vincent, G. 1997. Long QT syndrome: Sudden death in the young. American Heart Association's 24th Health and Science Journalists' Forum. Portland, Ore.
1996. New gene for heart rhythm abnormality. Science News 149(Jan. 13):31.
Roden, D., et al. 1996. Multiple mechanisms in the long QT syndrome: Current knowledge, gaps, and future directions. Circulation 94:1996.
Schwartz, P., M. Periti, and A. Malliani. 1975. The long QT syndrome. American Heart Journal 89:378.
Vincent, G., et al. 1992. The spectrum of symptoms and QT intervals in carriers of the gene for the long QT syndrome. New England Journal of Medicine 327:846.
Plants with a bug home advantage
Small tufts of hair on a plant can provide shelter to insects that benefit the plant.
Agrawal, A.A., and R. Karban. 1997. Domatia mediate plant-arthropod mutualism. Nature 387(June 5):562.
Cassava pest biologically suppressed
A predatory mite from Brazil is turning out to control a destructive cassava pest in Africa.
Strobel, G. 1993. Fighting bugs with bugs to save cassava. Science News 144(October 30):277.
Gene tells left from right
Mutations in a gene called lefty result in mice whose internal organs end up on the wrong sides of their bodies.
Hamada, H. 1997. Establishing left-right asymmetries in mammals. International Congress of Developmental Biology. Snowbird, Utah.
Worms and flies share a sexy gene
A gene involved in determining the sex of worms resembles one that performs similar duties in insects.
Raymond, C., et al. 1997. The nematode sexual regulator gene mab-3 resembles the fly sexual regulator doublesex. International Congress of Developmental Biology. Snowbird, Utah.
Blood screens may need a finer mesh
Current screening methods for blood donated in the United States may miss some viral fragments.
Zucker-Franklin, D., et al. 1997. Reexamination of human T cell lymphotropic virus (HTLV-I-II) prevalence. Proceedings of the National Academy of Sciences 94(June 10):6403.
Centers for Disease Control. 1988. Morbidity and Mortality Weekly Report 37:736, 745.
Gallo, R., and F. Wong-Staal. 1990. Retrovirus Biology and Human Disease. New York: Dekker.
Inhaled steroids linked to cataracts
Older people who used corticosteroid inhalers have a heightened risk of developing cataracts.
Chylack, L. 1997. Cataracts and inhaled corticosteroids. New England Journal of Medicine 337(July 3):46.
Cumming, R., et al. 1997. Use of inhaled corticosteroids and the risk of cataracts. New England Journal of Medicine 337(July 3):8.
Black, R., et al. 1960. Posterior subcapsular cataracts induced by corticosteroids in patients with rheumatoid arthritis. Journal of the American Medical Association 174:166.
Hodge, W., J. Whitcher, and W. Satariano. 1995. Risk factors for age related cataracts. Epidemiology Review 17:336.
Toogood, J., et al. 1993. Association of ocular cataracts with inhaled and oral steroid therapy during long term treatment of asthma. Journal of Allergy and Clinical Immunology 91:571.
The San Andreas' secret helpers
Scientists resolve a long-standing problem about how the Pacific tectonic plate manages to slide past North America.
Dickinson, W.R., and B.P. Wernicke. 1997. Reconciliation of San Andreas slip discrepancy by a combination of interior Basin and Range extension and transrotation near the coast. Geology 25(July):663.
Volcano dumps ash on Mexico City
The recent eruption of Popocatepetl was the biggest in more than 50 years.
Information on Popocatepetl is available on the World Wide Web at http://vulcan.wr.usgs.gov/Volcanoes/Popocatepetl/framework.html.
A Soil Story
Life inside a nematode: Creative chemistry and novel pest control
Bacteria generate light and produce red pigments that behave like antibiotics and crystals that may become useful insecticides.
Forst, S., and K. Nealson. 1996. Molecular biology of the symbiotic-pathogenic bacteria Xenorhabdus spp. and Photorhabdus spp. Microbiological Reviews 60(March):21.
1988. First gene-engineered pesticide tested. Science News 134(July 9):27.
Pennisi, E. 1992. Lab insect thwarts potent natural toxins. Science News 142(Sept. 12):166.
Travis, J. 1996. An illuminating partnership for squid. Science News 150(Sept. 14):167.
Wilson, E.O. 1992. The Diversity of Life. New York: W.W. Norton & Company.
From Microdevice to Smart Dust
Learning to build, program, and control multitudes of interacting micromachines
Microelectromechanical systems offer novel ways of maneuvering aircraft, moving around paper or microscopic parts, and performing aerial surveillance.
Berlin, A.A., and K.J. Gabriel. 1997. Distributed MEMS: New challenges for computation. IEEE Computational Science & Engineering 4(January-March):12.
Bohringer, Karl F., et al. 1997. Computational methods for design and control of MEMS micromanipulator arrays. IEEE Computational Science & Engineering 4(January-March):17.
Information on DARPA's MEMS program is available at http://eto.sysplan.com/ETO/MEMS/index.html.
The MEMS Clearinghouse is at http://mems.isi.edu.