Bacterial Toxin Surprises Scientists
...ria to kill competing bacteria. From their previous work, the scientists knew that a portion of colicin Ia changes from a harmless cluster of about 175 amino acids into a lethal structure that harpoons the inner membrane of its bacterial victim. The resulting hole, or c......und instead of studying the fossils themselves, as previous investigators had done. According to Ku, there is evidence that radioisotopes can migrate in and out of bone during the fossilization process, affecting the accuracy of dating. To double-check his data, Ku compared his mass spectrographic age determi...Component In Soy Products May Be Substitute For Estrogen Treatment
...n tolerate this better than other estrogens." Two previous studies by Potter that showed soy protein lowered bad cholesterollevels in men who used a similar diet were cited in the Aug. 3, 1995, issueof the New England Journal of Medicine as evidence of soy protein's healthbenefits. The new study is the first...North America Hit Hard By Asteroid Strike In Yucatan 65 Million Years Ago
...act, something scientists have rarelyconsidered in previous studies of this 65-million-year-old event," D'Hondtsaid.......ne, said the findings provide new insight into why previous epidemiologic studies may have failed to show a consistent association between cigarette smoking and breast cancer, when the association is clear in many other organs. "These findings on breast cancer require substantial replication, but the po...Duke's Russian Laser Making Ultraviolet Light And Gamma Rays
...ecise instant that ultraviolet lightcreated by the previous pulse was bouncing between the mirrors. Ultravioletlight and electrons thus interacted, resulting in a tremendous boost inenergy which converted ultraviolet light into gamma rays. Gamma rays are nature's most energetic kind of light, even more power...Researchers Corral Millions Of Microscopic Membranes
... can move freely about on a membrane's surface. In previous work, the researchers have demonstrated that they can use electric fields to concentrate such proteins against two-dimensional membrane boundaries. They suggest that it should be possible to both concentrate and crystallize such proteins by applying ...Ten Years of Progress For Superfund Basic Research Program
...l two-stepreactor will be much more effective than previous designs whichrequired two separate reactors. It alternates between anaerobic(no oxygen) and aerobic (with oxygen) degradation to chew up thedyes more completely. Bishop's group has also designed tiny probes which can measurethe concentration of oxyge...High Levels of Vitamin C Prove Toxic to HIV
...fected and healthy immune cells, after finding in previous studies that cancer cells also take in more glucose and vitamin C than normal cells. In addition, Dr. Golde and his colleagues were the first to prove, in 1993, that the same molecule that allows glucose into cells also serves as a route for vitami...President's Budget Proposal Cuts R&D By 14 Percent By 2002
...on since July 1995 has shown some improvement over previous projections in terms of future support for R&D programs," said Al Teich, director of the AAAS Science and Policy Programs . "Improved economic forecasts and concerted efforts to protect R&D have helped diminish some of the massive cuts previously ...Teens Shop "Healthy", But Trust Label Claims Too Much
...e journal, Adolescence, the researchers write, "A previous marketing survey conducted by Food and Beverage Marketing and Forecast Magazine in 1988 did not show that health-related factors played a significant role." Achterberg says the fact that the Penn State researcher's study showed that teenagers w......explicably, the numbers rose by 3 percent from the previous year. The trick for penguin survival is getting beyond the first fledgling year, says Boersma. "Once they get to be adults, about 90 percent survive from year to year." Fishing fleets are not the penguins' only harbinger of death. Oil tankers also ar...Duke researchers find existing drugs can stop fungus that attacks AIDS patients
...e believe we have found one such target." In previous research, Heitman showed cyclosporin and FK506, two leadinganti-organ rejection drugs, both jam the mechanism that activates immunesystem cells by blocking a single target inside cells, a protein calledcalcineurin. Since the drugs only work at ...Low Iron Levels Cause Weakness In Women Who Are Not Anemic
... iron depletion without anemia. They do know from previous studies, however, that iron-deficient but non-anemic rats have impaired endurance capacity when compared with normal rats. Haas and Zhu set out to determine whether mild iron deficiencies affect work. Since studying women working in fields would be ...New Evidence For Corn's Ancestry Could Lead To Insect And Drought Resistant Crops
...y other teosinte varieties had failed. Similarly, previous attempts by breeders to cross Tripsacum withcorn always resulted in sterile plants. But Eubanks found she could alsosuccessfully breed corn with some of her Tripsacum and Zea diploperennis crosses. Since fertile offspring implies genetic simila...Summer Science: Firefly Babies Advertise Their Bitter Taste, UD Researchers Say
...out whether mice think firefly larvaetaste bad. In previous laboratory studies, vertebrate predators have consistently turned uptheir noses at lucibufagins, compounds present in adult fireflies. But, Tallamynotes, "only anecdotal evidence suggested that larvae are also distasteful." So,mice were offered a cho...Resistance To Leptin Contributes To Obesity
...ction in the number of calories eaten." In previous studies, Friedman and his colleagues discovered leptinand documented weight loss in genetically obese and normal mice given dailyinjections of the protein for two weeks. These early studies required highdose injections of leptin. In the current stu...UW Smogmobile Offers Cleaner, Safer Alternative To Gas Or Electric Cars
...ys, the cold temperature is precisely what stalled previous efforts to develop a liquid nitrogen vehicle. Researchers have known for decades that pressure built up when super-cooled liquid nitrogen is converted to a gas could power a car. But the UW group was the first to develop a heat exchanger system that ...Oaks' Defenses Help Gypsy Moth Caterpillar Fend Off Virus
...aterpillars eat the dormant virusleft on leaves by previous victims. When the caterpillar eats the virus,together with the oak leaf and its tannin, the virus becomes activated. "We thought the tannin acted by itself, that it did something to theviral proteins," Appel told attendees at the Ecological ......nce from only a single parent -- and disproved the previous theory that it was recessive and had to be inherited from both parents. One of the most immediate applications of this discovery will be theavailability of a simple, inexpensive blood test to confirm whether childrenwith dystonia symptoms have this ...