http://www.scienceweek.cz Aktuální články ze světa vědy, techniky a výzkumu 60 http://www.scienceweek.cz/strain-gating-piezotronics-new-class-of-piezoelectric-logic-devices-created-using-zinc-oxide-nanowires-iid-229747 Researchers have developed a new class of electronic logic device in which current is switched by an electric field generated by the application of mechanical strain to zinc oxide nanowires. 2010-09-03 04:22:51 http://www.scienceweek.cz/water-in-earths-mantle-key-to-survival-of-oldest-continents-iid-229746 Earth today is one of the most active planets in the Solar System, and was probably even more so during the early stages of its life. Thanks to the plate tectonics that continue to shape our planet's surface, remnants of crust from Earth's formative years are rare, but not impossible to find. A new paper examines how some ancient rocks have resisted being recycled into Earth's convecting interior. 2010-09-03 04:22:51 http://www.scienceweek.cz/drugs-used-to-treat-osteoporosis-not-linked-with-higher-risk-of-esophageal-cancer-iid-229745 Although some reports have suggested a link between the use of oral bisphosphonates (drugs that prevent the loss of bone mass) and esophageal cancer, analysis of medical data from more than 80,000 patients in the United Kingdom found that use of these drugs was not significantly associated with new cases of esophageal or gastric cancer, according to a new study. 2010-09-03 04:22:48 http://www.scienceweek.cz/cuckoo-chicks-in-zebra-finches-eggs-from-other-females-can-be-found-in-every-fifth-nest-iid-229744 Some female zebra finches foist a part of their eggs on their neighbors. Scientists in Germany have discovered that in every fifth nest there is one egg that is not produced by its social parents. The female birds act in a very well-targeted way: eggs are being placed in “foster-care” shortly before the hosts commence their own egg laying. 2010-09-03 04:22:47 http://www.scienceweek.cz/long-term-use-of-oral-bisphosphonates-may-double-risk-of-esophageal-cancer-study-finds-iid-229743 People who take oral bisphosphonates for bone disease over five years may be doubling their risk of developing esophageal cancer (cancer of the gullet), according to a new study. 2010-09-03 04:22:45 http://www.scienceweek.cz/value-of-oxygen-therapy-in-end-of-life-care-challenged-in-new-study-iid-229742 Millions of patients with advanced disease in palliative care settings receive oxygen therapy to help them breathe more easily. But a new study says roughly half of them don't benefit from the intervention, and among those who do benefit, it doesn't make a bit of difference whether they get pure oxygen or just plain old room air -- both offer equal benefit. 2010-09-03 04:22:44 http://www.scienceweek.cz/new-warning-signs-may-predict-kidney-transplant-failure-iid-229741 Kidney transplants that show a combination of fibrosis (scarring) and inflammation after one year are at higher risk of long-term transplant failure, according to a new study. 2010-09-03 04:22:43 http://www.scienceweek.cz/cigarette-smoke-may-contribute-to-lung-inflammation-through-a-new-chemical-pathway-iid-229740 Cigarette smoke shuts off a key enzyme in airways that regulates the body's response to inflammation, according to new findings. Researchers say smoke inhibits the enzyme, called Leukotriene A4 Hydrolase (LTA4H), causing it to fail in its job of shutting down white blood cells following a successful response to inflammation. 2010-09-03 04:22:41 http://www.scienceweek.cz/serendipity-contributes-to-mrsa-susceptibility-findings-iid-229739 Researchers have found two genes in mice which might help identify why some people are more susceptible than others to potentially deadly staph infections. 2010-09-03 04:22:41 http://www.scienceweek.cz/social-networks-influence-health-behaviors-iid-229738 Individuals are more likely to acquire new health practices while living in networks with dense clusters of connections -- that is, when in close contact with people they already know well. 2010-09-03 04:22:40 http://www.scienceweek.cz/laser-based-missile-defense-for-helicopters-being-developed-iid-229737 Protecting helicopters in combat from heat-seeking missiles is the goal of new laser technology. 2010-09-03 04:22:40 http://www.scienceweek.cz/experiment-records-ultrafast-chemical-reaction-with-vibrational-echoes-iid-229736 To watch a magician transform a vase of flowers into a rabbit, it's best to have a front-row seat. Likewise, for chemical transformations in solution, the best view belongs to the molecular spectators closest to the action. Those special molecules comprise the "first solvation shell," and although it has been known for decades that they can sense and dictate the fate of nearly every chemical reaction, it has been virtually impossible to watch them respond -- until now. 2010-09-03 04:22:39 http://www.scienceweek.cz/children-who-eat-vended-snack-foods-face-chronic-health-problems-poor-diet-study-finds-iid-229735 School children who consume foods purchased in vending machines are more likely to develop poor diet quality -- and that may be associated with being overweight, obese or at risk for chronic health problems such as diabetes and coronary artery disease, according to new research. 2010-09-03 04:22:39 http://www.scienceweek.cz/sciences-policy-clout-diminished-but-oil-risk-looms-large-study-finds-iid-229734 More people are likely to believe scientific studies claiming that oil drilling is riskier, not safer, than was previously thought, according to a new study of attitudes in California. What's more the findings show that scientists' efforts to influence public opinion have a limited effect. 2010-09-03 04:22:38 http://www.scienceweek.cz/computer-technique-could-help-partially-sighted-see-better-iid-229733 Thousands of people who are partially sighted following stroke or brain injury could gain greater independence from a simple, cheap and accessible training course which could eventually be delivered from their mobile phones or hand-held games consoles, according to a new study. 2010-09-03 04:22:37 http://www.scienceweek.cz/cancer-causing-gene-crucial-in-stem-cell-development-study-finds-iid-229732 A research team has shown for the first time that a gene called Myc, which is traditionally thought of as a cancer-causing gene, may be far more important in the development and persistence of stem cells than was known before. 2010-09-03 04:22:36 http://www.scienceweek.cz/technique-to-trace-persistent-cfcs-iid-229748 Ultrafine measurements of atmospheric gases could help scientists track down the last sources of CFCs thought to be slowing the recovery of the ozone hole. 2010-09-03 02:49:58 http://www.scienceweek.cz/openness-urged-on-uks-emissions-iid-229749 The government's chief environment scientist calls for more openness in admitting the UK's cuts in greenhouse gas emissions are an illusion. 2010-09-03 02:49:34 http://www.scienceweek.cz/occurrence-of-increased-kidney-transplant-listings-in-patients-with-prior-non-kidney-transplants-iid-229721 Individuals who received a non-kidney organ transplant in the past may be more likely to be listed for a kidney transplant prior to initiation of dialysis (pre-emptive listing) than other candidates, according to a study appearing in an upcoming issue of the Clinical Journal of the American Society Nephrology (CJASN). The results indicate that the growth in the numbers of this group of kidney transplant candidates adds to the list of organ allocation challenges. 2010-09-03 02:23:17 http://www.scienceweek.cz/bp-removes-cap-from-plugged-well-in-gulf-of-mexico-iid-229720 BP on Thursday removed a massive cap which had stemmed the flow of oil from its ruptured well deep in the Gulf of Mexico in a key step toward killing the well once and for all, officials said. 2010-09-03 02:23:17