Global biodiversity surveys over the past few years have provided increasing evidence that our planet is in the midst of its sixth mass extinction. Plants, animals, and microorganisms are disappearing thousands of times more rapidly than they have for more than 65 million years, and for the first time in Earth's history, human activity is the predominant force behind this mass extinction. As governments and conservation organizations around the world attempt to stem this tide of disappearing species, they face a number of formidable challenges, but perhaps the greatest ...

An infrequently used blood test can effectively identify individuals at increased risk of developing complications associated with chronic kidney disease (CKD), according to a study appearing in an upcoming issue of the Journal of the American Society Nephrology (JASN). Use of this simple test might help physicians identify persons with CKD who are at high risk for complications, and identify persons with impaired kidney function at earlier stages of disease. To assess kidney function, doctors most often measure an individual's level of creatinine in the blood. Creatinine ...

Researchers at the University of Iowa have pinpointed the part of the brain that causes people to experience fear – a discovery that could improve treatment of post-traumatic stress disorder (PTSD) and other anxiety conditions. Published today in the journal Current Biology, the study investigates how the emotion of fear depends on an almond-shaped brain region called the amygdala. The patient in the case study has a rare condition that destroyed her amygdala. UI researchers observed the patient's response to frightening stimuli such as a haunted house, snakes, spiders, ...

The finding offers a powerful take on the connection between the brain and behavior, specifically in the context of situations that would normally evoke fear, the researchers say. "The nature of fear is survival and the amygdala helps us stay alive by avoiding situations, people, or objects that put our life in danger," said Justin Feinstein of the University of Iowa. "Because SM is missing her amygdala, she is also missing the ability to detect and avoid danger in the world. It is quite remarkable that she is still alive." Feinstein says that the average person may ...

Naturally occurring high hemoglobin levels are safe for kidney disease patients on dialysis, according to a study appearing in an upcoming issue of the Journal of the American Society Nephrology (JASN). The results suggest that there is no need to lower these levels to protect patients' health. The vast majority of individuals who develop advanced chronic kidney disease (CKD) also develop progressive anemia, or red blood cell deficiency, that must be treated with medication. Prior to the approval of such erythropoiesis-stimulating agents in 1989, many dialysis patients ...

Cystatin C, a blood marker of kidney function, proved significantly more accurate than the standard blood marker, creatinine, in predicting serious complications of kidney disease, in a study by researchers at the San Francisco VA Medical Center and the University of California, San Francisco. Among adults who were identified as having chronic kidney disease by high creatinine levels, the researchers found that only patients who also had abnormally high levels of cystatin C were at high risk for death, cardiovascular disease, heart failure, or kidney failure. People with ...

A new study provides fascinating insight into the underlying pathology associated with the autoimmune disease, systemic lupus erythematosus (SLE). The research, published by Cell Press in the December issue of the journal Immunity, reveals an unexpected role for a key type of immune cell and provides a potential new therapeutic strategy for SLE and, potentially, other autoimmune diseases. SLE is a chronic systemic disease that can affect many regions of the body and, as a result, presents with diverse clinical symptoms. As is characteristic of other autoimmune disease, ...

Until this year, all human-made objects have moved according to the laws of classical mechanics. Back in March, however, a group of researchers designed a gadget that moves in ways that can only be described by quantum mechanics—the set of rules that governs the behavior of tiny things like molecules, atoms, and subatomic particles. In recognition of the conceptual ground their experiment breaks, the ingenuity behind it and its many potential applications, Science has called this discovery the most significant scientific advance of 2010. Physicists Andrew Cleland and ...

SALT LAKE CITY, Dec. 16, 2010 – University of Utah physicists stored information for 112 seconds in what may become the world's tiniest computer memory: magnetic "spins" in the centers or nuclei of atoms. Then the physicists retrieved and read the data electronically – a big step toward using the new kind of memory for both faster conventional and superfast "quantum" computers. "The length of spin memory we observed is more than adequate to create memories for computers," says Christoph Boehme (pronounced Boo-meh), an associate professor ...

The greater susceptibility of humans to certain infectious diseases when compared to other primates could be explained by species-specific changes in immune signaling pathways, a University of Chicago study finds. The first genome-wide, functional comparison of genes regulated by the innate immune system in three primate species discovers potential mediators of differences in disease susceptibility among primates. These findings are published on December 16 in the open-access journal PLoS Genetics. Humans are more sensitive than chimpanzees to the severe effects of certain ...

December 16, 2010 - Scientists have discovered that a class of materials known to convert heat to electricity and vice versa behaves quite unexpectedly at the nanoscale in response to changes in temperature. The discovery - described in the December 17, 2010, issue of Science - is a new "opposite-direction" phase transition that helps explain the strong thermoelectric response of these materials. It may also help scientists identify other useful thermoelectrics, and could further their application in capturing energy lost as heat, for example, in automotive and factory ...

CAMBRIDGE, Mass. -- Researchers have created a powerful new approach to scholarship, using approximately 4 percent of all books ever published as a digital "fossil record" of human culture. By tracking the frequency with which words appear in books over time, scholars can now precisely quantify a wide variety of cultural and historical trends. The four-year effort, led by Harvard University's Jean-Baptiste Michel and Erez Lieberman Aiden, is described this week in the journal Science. The team, comprising researchers from Harvard, Google, Encyclopaedia Britannica, ...

New genes that have evolved in species as little as one million years ago – a virtual blink in evolutionary history – can be just as essential for life as ancient genes, startling new research has discovered. Evolutionary biologists have long proposed that the genes most important to life are ancient and conserved, handed down from species to species as the "bread and butter" of biology. New genes that arise as species split off from their ancestors were thought to serve less critical roles – the "vinegar" that adds flavor to the core genes. But when nearly 200 new ...

Gamma-ray bursts (GRBs), fleeting events that last from less than a second to several minutes, are detected by orbiting observatories that can pick up their high energy radiation. Thirteen years ago, however, astronomers discovered a longer-lasting stream of less energetic radiation coming from these violent outbursts, which can last for weeks or even years after the initial explosion. Astronomers call this the burst's afterglow. While all gamma-ray bursts [1] have afterglows that give off X-rays, only about half of them were found to give off visible light, with the ...

Nearly two-thirds of Medicare beneficiaries discharged from hospitals after ischemic stroke die or are readmitted within one year, researchers report in Stroke: Journal of the American Heart Association. Stroke is the second leading cause of hospital admissions among older adults in the United States, according to American Heart Association/American Stroke Association statistics. Ischemic stroke, which occurs as a result of an obstruction within a blood vessel supplying blood to the brain, accounts for 87 percent of all strokes. Only a few contemporary studies have ...

A UCLA-led has study found that after leaving the hospital, nearly two-thirds of Medicare beneficiaries hospitalized for acute ischemic stroke either died or were rehospitalized within a year. The findings point to an opportunity for more quality-of-care initiatives to improve stroke care, especially in transitioning to home, stroke rehabilitation and outpatient care. The study, which appears online Dec. 16 in Stroke, a journal of the American Heart Association, also found that hospital mortality and readmission rates varied widely nationwide, indicating there ...

Researchers from Mount Sinai School of Medicine have found that when one copy of the SHANK3 gene in mice is missing, nerve cells do not effectively communicate and do not show cellular properties associated with normal learning. This discovery may explain how mutations affecting SHANK3 may lead to autism spectrum disorders (ASDs). The research is currently published in Molecular Autism. "We know that SHANK3 mutation plays a central, causative role in some forms of autism spectrum disorders, but wanted to learn more about how it does this," said Joseph Buxbaum, PhD, Director ...

CHAPEL HILL, N.C. – The function of histones -- the proteins that enable yards of DNA to be crammed into a single cell -- depends on a number of chemical tags adorning their exterior. This sophisticated chemical syntax for packaging DNA into tight little coils or unraveling it again -- called the "histone code" -- is the latest frontier for researchers bent on understanding how genetics encodes life. But recent research from the University of North Carolina at Chapel Hill has found a number of issues with histone antibodies, the main tools used to decipher this code, ...

A research team from the Institut Català de Nanotecnologia (ICN), in Barcelona, has demonstrated a device that induces electron spin motion without net electric currents, a key step in developing the spin computers of the future. The results are published in the Dec 17 issue of the journal Science. The authors are Marius V. Costache and Sergio O. Valenzuela, an ICREA Professor who is leader of the Physics and Engineering of Nanodevices Group at ICN. Spintronics is a branch of electronics that aims to use the electron spin rather than its charge to transport and store ...

The research project 'Older People's Use of Unfamiliar Space' (OPUS) examined the strategies used by older people to find their way in unfamiliar spaces as pedestrians and users of public transport. As part of the research, older people were shown town scenes and pedestrian routes and gave feedback on signposting, ease of navigation and general impressions. Their heart rates were measured to monitor stress levels. Participants were also taken to a town centre to walk through the same routes in person. Initial findings show: Signs are of limited use even in unfamiliar ...

Scientists at the Johns Hopkins Kimmel Cancer Center have deciphered the genetic code for medulloblastoma, the most common pediatric brain cancer and a leading killer of children with cancer. The genetic "map" is believed to be the first reported of a pediatric cancer genome and is published online in the December 16 issue of Science Express. Notably, the findings show that children with medulloblastoma have five- to tenfold fewer cancer-linked alterations in their genomes compared with their adult counterparts, the scientists say. "These analyses clearly show that ...

Pediatric cancer researchers at The Children's Hospital of Philadelphia contributed important expertise to a new landmark study of medulloblastoma, a type of brain tumor typically found in children. The large multicenter study defines the genetic landscape of this cancer, and holds intriguing clues to gene changes on signaling pathways that may become fruitful targets for future therapies. The most common cancerous brain tumor in children, medulloblastoma is, fortunately, rare. However, it causes significant mortality, and survivors may suffer serious long-term side effects ...

AMES, Iowa – Advancements in fabrication technologies may lead to superlenses and other designer optical materials, according to an Iowa State University and Ames Laboratory physicist. In an article titled "Improving Metamaterials" published in the Perspectives section of the Dec. 17 issue of the journal Science, Costas Soukoulis and Martin Wegener write about the man-made materials designed to deliver certain properties not found in nature. Soukoulis is an Iowa State University Distinguished Professor and Frances M. Craig Professor of Physics and Astronomy and a senior ...

Researchers from Italy determined that radiofrequency ablation (RFA) is a safe and effective therapy for managing hepatocellular carcinoma (HCC) in cirrhotic patients. The high repeatability of RFA is advantageous in controlling recurrences of cancerous tumors in the liver. Results of this 10-year retrospective study are available in the January 2011 issue of Hepatology, a journal published by Wiley-Blackwell on behalf of the American Association for the Study of Liver Diseases (AASLD). HCC is the third leading cause of death from cancer worldwide and according to the ...

In the war on cancer, perhaps there is nothing more powerful in a physician's arsenal than early detection. Despite recent advances in early detection and treatment, breast cancer remains a common and significant health problem in the United States and worldwide. Approximately one in ten women will get breast cancer in their lifetime and more than half of women with late stage cancer (II and III) have no cure or effective therapeutic available. Using a new, powerful method for rapidly screening molecules associated with disease, proteomics expert Joshua LaBaer and colleagues ...