To make decisions, we need to estimate the value of sensory stimuli and motor actions, their "goodness" and "badness." We can imagine that good and bad are two ends of a single continuum, or dimension, of value. This would be analogous to the single dimension of light intensity, which ranges from dark on one end to bright light on the other, with many shades of gray in between. Past models of behavior and learning have been based on a single continuum of value, and it has been proposed that a particular group of neurons (brain cells) that use dopamine as a neurotransmitter ...

Washington, DC—Researchers reviewed the likelihood of continued changes to the terrestrial climate, including an analysis of a collection of 27 climate models. If emissions of heat-trapping gases continue along the recent trajectory, 21st century mean annual global warming could exceed 3.6 °F ( 2 °C) over most terrestrial regions during 2046 to 2065 and 7.2 °F (4 °C) during 2081-2100. If warming occurs at this pace, it will probably be the most rapid large climate change in the last 65 million years. The review, published in the August 2 issue of Science, was conducted ...

Two women have the same genetic mutation – an abnormal BRCA1 gene that puts them both at much higher-than-average risk for breast cancer – but only one woman develops the disease. Why? Michigan State University genetic scientists have begun to understand the mechanisms behind the phenomena. "It's been known for a while that genetic mutations can modify each other," explained Ian Dworkin, MSU associate professor of zoology. "And we also know that the subtle differences in an individual's genome – what scientists call wild type genetic background -- also affects how mutations ...

BERKELEY — Shifts in climate are strongly linked to human violence around the world, with even relatively minor departures from normal temperature or rainfall substantially increasing the risk of conflict in ancient times or today, according to a new study by researchers at the University of California, Berkeley, and Princeton University. The results, which cover all major regions of the world and show similar patterns whether looking at data from Brazil, China, Germany, Somalia or the United States, were published today (Thursday, Aug. 1) in the journal Science. By ...

STANFORD, Calif. — Mitochondrial Eve and Y-chromosomal Adam — two individuals who passed down a portion of their genomes to the vast expanse of humanity — are known as our most recent common ancestors, or MRCAs. But many aspects of their existence, including when they lived, are shrouded in mystery. Now, a study led by the Stanford University School of Medicine indicates the two roughly overlapped during evolutionary time: from between 120,000 to 156,000 years ago for the man, and between 99,000 and 148,000 years ago for the woman. "Previous research has indicated that ...

Monash University researchers have brought next generation energy storage closer with an engineering first - a graphene-based device that is compact, yet lasts as long as a conventional battery. Published today in Science, a research team led by Professor Dan Li of the Department of Materials Engineering has developed a completely new strategy to engineer graphene-based supercapacitors (SC), making them viable for widespread use in renewable energy storage, portable electronics and electric vehicles. SCs are generally made of highly porous carbon impregnated with a ...

LA JOLLA, CA – August 1, 2013 – Scientists at The Scripps Research Institute (TSRI) have achieved the first efficient chemical synthesis of ingenol, a highly complex, plant-derived compound that has long been of interest to drug developers for its anticancer potential. The achievement will enable scientists to synthesize a wide variety of ingenol derivatives and investigate their therapeutic properties. The achievement also sets the stage for the efficient commercial production of ingenol mebutate, a treatment for actinic keratosis (a common precursor to non-melanoma skin ...

Scientists have identified a molecule that enables starfish to carry out one of the most remarkable forms of feeding in the natural world. A starfish feeds by first extending its stomach out of its mouth and over the digestible parts of its prey, such as mussels and clams. The prey tissue is partially digested externally before the soup-like "chowder" produced is drawn back into its 10 digestive glands. The researchers at Queen Mary, University of London and the University of Warwick have discovered a neuropeptide -- a molecule which carries signals between neurons -- ...

A Clostridium difficile (C. diff) infection is one that can affect the digestive system and most commonly affects people staying in hospital. It is not generally a problem for healthy people but may infect those on antibiotics with an imbalance of 'good bacteria' in the gut. A research paper published today, 2nd August 2013, in BMC Infectious Diseases has for the first time identified a unique four-point test using easily measurable clinical variables which can be used to accurately predict the death risk to patients from C. diff. Accurate prediction means that those ...

Temperature-driven changes alter outbreak patterns of tea tortrix -- an insect pest -- and may shed light on how temperature influences whether insects emerge as cohesive cohorts or continuously, according to an international team of researchers. These findings have implications for both pest control and how climate change may alter infestations. "While the influence of temperature on individual-level life-history traits is well understood, the impact on population-level dynamics, such as population cycles or outbreak frequency is less clear," the researchers report in ...

Athens, Ga. – Climate change is affecting the spread of infectious diseases worldwide, according to an international team of leading disease ecologists, with serious impacts to human health and biodiversity conservation. Writing in the journal Science, they propose that modeling the way disease systems respond to climate variables could help public health officials and environmental managers predict and mitigate the spread of lethal diseases. The issue of climate change and disease has provoked intense debate over the past decade, particularly in the case of diseases ...

A University of Colorado Boulder team has developed a radically new technique that uses the power of sunlight to efficiently split water into its components of hydrogen and oxygen, paving the way for the broad use of hydrogen as a clean, green fuel. The CU-Boulder team has devised a solar-thermal system in which sunlight could be concentrated by a vast array of mirrors onto a single point atop a central tower up to several hundred feet tall. The tower would gather heat generated by the mirror system to roughly 2,500 degrees Fahrenheit (1,350 Celsius), then deliver it ...

Washington, DC (August 1, 2013) — Even early stages of kidney disease come with steep medical costs, according to a study appearing in an upcoming issue of the Journal of the American Society of Nephrology (JASN). The study found that expenses related to moderate chronic kidney disease (CKD) cost Medicare tens of billions of dollars each year. Approximately 60 million people globally have CKD. Most of the costs of CKD are thought to arise when the disease progresses to kidney failure, also known as stage 5 CKD. The Centers for Disease Control and Prevention funded investigators ...

The planet is undergoing one of the largest changes in climate since the dinosaurs went extinct. But what might be even more troubling for humans, plants and animals is the speed of the change. Stanford climate scientists warn that the likely rate of change over the next century will be at least 10 times quicker than any climate shift in the past 65 million years. If the trend continues at its current rapid pace, it will place significant stress on terrestrial ecosystems around the world, and many species will need to make behavioral, evolutionary or geographic adaptations ...

ANN ARBOR, Mich. — More than 7 billion people live on this planet – members of a single species that originated in one place and migrated all over the Earth over tens of thousands of years. But even though we all trace our family lineage to a few common ancestors, scientists still don't know exactly when and how those few ancestors started to give rise to the incredible diversity of today's population. A brand-new finding, made using advanced analysis of DNA from all over the world, sheds new light on this mystery. By studying the DNA sequence of Y chromosomes of ...

Should climate change trigger the upsurge in heat and rainfall that scientists predict, people may face a threat just as perilous and volatile as extreme weather — each other. Researchers from Princeton University and the University of California-Berkeley report in the journal Science that even slight spikes in temperature and precipitation have greatly increased the risk of personal violence and social upheaval throughout human history. Projected onto an Earth that is expected to warm by 2 degrees Celsius by 2050, the authors suggest that more human conflict is a likely ...

SAN FRANCISCO, August 1, 2013 -- Why do shopping addicts keep spending even in the face of harmful financial, emotional and social consequences? A new study suggests poor credit management and a belief that new purchases will create a happier life fuel compulsive buying. Approximately 10 percent of adults in Western countries are believed to have a compulsive spending disorder that leads them to lose control over their buying behavior, and the trend is on the rise. These shopaholics are addicted to buying things, regardless of whether they want or need them. In a new ...

NEW YORK (Aug. 1, 2013) -- The enormous promise of regenerative medicine is matched by equally enormous challenges. But a new finding by a team of researchers led by Weill Cornell Medical College has the potential to improve both the safety and performance of reprogrammed cells. The researchers' study, published in today's issue of the journal Nature, found that an enzyme, activation-induced cytidine deaminase (AID), helps in the process that changes an adult human cell into an induced pluripotent stem cell (iPS cell). These iPS cells can then be developed into any kind ...

Irvine, Calif., Aug. 1, 2013 — Scientists from UC Irvine and the National Center for Atmospheric Research have developed a new computer model to measure global warming's effect on soil worldwide that accounts for how bacteria and fungi in soil control carbon. They found that soil outcomes based on their microbial model were more reliable than those forecast by traditional models. Study results appear online in Nature Climate Change. While standard models project modest carbon losses with global warming, the microbial models generate two novel scenarios: One is that ...

LA JOLLA, CA – August 1, 2013 – Scientists at The Scripps Research Institute (TSRI) have discovered a new type of chemical modification that affects numerous proteins within mammalian cells. The modification appears to work as a regulator of important cellular processes including the metabolism of glucose. Further study of this modification could provide insights into the causes of diabetes, cancer and other disorders. "It appears to be an intrinsic feedback mechanism in glucose metabolism, but I suspect that its other functions throughout the cell will prove at least ...

(Boston) – In an article published in this month's issue of Pediatrics In Review, researchers from Boston University School of Medicine (BUSM) stress the importance of physicians recognizing that many mothers use herbal supplements while breastfeeding in order to make accurate health assessments for both mother and child. In the US, no existing regulatory guidelines set a standardized risk assessment of herbal supplement use during breastfeeding. Because of the highly limited number of studies on herb use during lactation, numerous resources have mixed reports and safety ...

COLLEGE PARK, Md - A discovery by a University of Maryland-led research team offers hope for treating "lazy eye" and other serious visual problems that are usually permanent unless they are corrected in early childhood. Amblyopia afflicts about three percent of the population, and is a widespread cause of vision loss in children. It occurs when both eyes are structurally normal, but mismatched – either misaligned, or differently focused, or unequally receptive to visual stimuli because of an obstruction such as a cataract in one eye. During the so-called "critical ...

ENERGY – Green battery . . . By substituting lignin for highly engineered, expensive graphite to make battery electrodes, researchers have developed a process that requires fewer steps and offers better performance. Renewable Electrodes from Wood Products, or ReNEW-PRO, is a low-cost lithium-ion battery anode made inexpensively from lignin, a renewable resource and byproduct of the pulp and paper industry. ReNEW-PRO was developed in collaboration with GrafTech International Holdings. The ORNL team was led by Orlando Rios of the Materials Science and Technology Division. ...

Researchers from the University of Illinois at Chicago College of Medicine have identified a characteristic unique to cancer cells in an animal model of cancer -- and they believe it could be exploited as a target to develop new treatment strategies. An enzyme that metabolizes the glucose needed for tumor growth is found in high concentrations in cancer cells, but in very few normal adult tissues. Deleting the gene for the enzyme stopped the growth of cancer in laboratory mice, with no associated adverse effects, reports Nissim Hay, UIC professor of biochemistry and molecular ...

Las Cumbres Observatory Global Telescope (LCOGT), with first lights at nine new 1-meter telescopes since April of 2012, achieved another critical milestone by capturing the first on-sky image with a production Sinistro camera. In development for over six years, the camera is arguably more important than the telescopes that will use them. "A telescope is really nothing more than a large camera lens," explained Joe Tufts, instrumentation scientist on the Sinistro project. "A large, precise, stable, and very expensive camera lens." Sinistro is the primary science camera ...