日期:2014-04-25 The smallest, most abundant marine microbe, Prochlorococcus, is a photosynthetic bacteria species essential to the marine ecosystem. An estimated billion billion billion of the single-cell creatures live in the oceans, forming the base of the marine... 阅读全文>>

日期:2014-04-25 Despite a well-documented history of dramatic genetic decay, the human Y chromosome has over the course of millions of years of evolution managed to preserve a small set of genes that has ensured not only its own survival but also the survival of me... 阅读全文>>

日期:2014-04-23 Stem cells -- the body's master cells -- demonstrate a bizarre property never before seen at a cellular level, according to a study published today from scientists at the University of Cambridge. The property -- known as auxeticity(拉胀性) -- is o... 阅读全文>>

日期:2014-04-23 Muscle weakness is a common symptom of both long-time alcoholics and patients with mitochondrial(线粒体的) disease. Now researchers have found a common link: mitochondria that are unable to self-repair. The results will be published online April 2... 阅读全文>>

日期:2014-04-23 With gene expression analysis growing in importance for both basic researchers and medical practitioners, researchers at Carnegie Mellon University and the University of Maryland have developed a new computational method that dramatically speeds up... 阅读全文>>

日期:2014-04-23 On Earth Week--and in fact, every week now--trees in mountains across the western United States are dying, thanks to an infestation of bark beetles that reproduce in the trees' inner bark. Some species of the beetles, such as the mountain pine beetl... 阅读全文>>

日期:2014-04-23 In parallel with modern man (Homo sapiens), there were other, extinct types of humans with whom we lived side by side, such as Neanderthals and the recently discovered Denisovans of Siberia. Yet only Homo sapiens survived. What was it in our genetic... 阅读全文>>

日期:2014-04-23 Using fish bred at Washington State University, an international team of researchers has mapped the genetic profile of the rainbow trout, a versatile salmonid whose relatively recent genetic history opens a window into how vertebrates evolve. The 30... 阅读全文>>

日期:2014-04-19 A possible break in the mystery of the missing Malaysia Airlines Flight 370 plane came when ships detected pings consistent with the aircraft's black box. But how does a black box actually work? 据报道,搜寻船只探测到疑似客机黑匣子的脉冲信号,这是失... 阅读全文>>

日期:2014-04-19 An international research team led by Cesar A. Arias, M.D., Ph.D., at The University of Texas Health Science Center at Houston (UTHealth) has identified a new superbug that caused a bloodstream infection in a Brazilian patient. The report appeared i... 阅读全文>>

日期:2014-04-19 Ancient Earth might have had an extraterrestrial supply of vitamin B3 delivered by carbon-rich meteorites, according to a new analysis by NASA-funded researchers. The result supports a theory that the origin of life may have been assisted by a suppl... 阅读全文>>

日期:2014-04-19 Chimpanzees may select a certain type of wood, Ugandan Ironwood, over other options for its firm, stable, and resilient properties to make their bed, according to a study published April 16, 2014 in the open-access journal PLOS ONE by David Samson f... 阅读全文>>

日期:2014-04-19 Several parasites and pathogens that devastate honeybees in Europe, Asia and the United States are spreading across East Africa, but do not appear to be impacting native honeybee populations at this time, according to an international team of resear... 阅读全文>>

日期:2014-04-19 In the most densely forested and most densely populated quadrant(象限) of the United States, forests reflect two centuries of human needs, values and practices. Disturbances associated with those needs, such as logging and clearing forests for agr... 阅读全文>>

日期:2014-04-19 The cause of neuronal death in Parkinson's disease is still unknown, but a new study proposes that neurons may be mistaken for foreign invaders and killed by the person's own immune system, similar to the way autoimmune diseases like type I diabetes... 阅读全文>>

日期:2014-04-18 Fruit flies are pretty predictable when it comes to scheduling their days, with peaks of activity at dawn and dusk and rest times in between. Now, researchers reporting in the Cell Press journal Cell Reports on April 17th have found that the cluster... 阅读全文>>

日期:2014-04-18 In a time of global climate change and rapidly disappearing habitat critical to the survival of countless endangered species, there is a heightened sense of urgency to confirm the return of animals thought to be extinct, or to confirm the presence o... 阅读全文>>

日期:2014-04-18 Wildfires across the western United States have been getting bigger and more frequent over the last 30 years -- a trend that could continue as climate change causes temperatures to rise and drought to become more severe in the coming decades, accord... 阅读全文>>

日期:2014-04-17 An international team of scientists has discovered new relationships between deep-sea temperature and ice-volume changes to provide crucial new information about how the ice ages came about. Researchers from the University of Southampton, the Nation... 阅读全文>>

日期:2014-04-17 From far away, the top of a leaf looks like one seamless surface; however, up close, that smooth exterior is actually made up of a patchwork(拼缀物) of cells in a variety of shapes and sizes. Interested in how these cells individually take on thei... 阅读全文>>

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