LIFE ON EARTH - Reconstructing the emergence and evolution of life on our planet is tightly linked to the questions as to when and to what extent Earth's atmosphere became oxygenated. New geological studies based on data from Western Greenland indicate that small levels of atmospheric oxygen developed already 3.8 billion years ago, some 0.7-0.8 billion years earlier than previously thought.

People diagnosed with depression are about twice as likely to smoke as the general population. A survey of 6811 participants from Australia, Canada, the United Kingdom, and the USA, published today in the scientific journal Addiction, found that although depressed smokers tried to quit smoking more often than other smokers, they were more likely to return to smoking within a month. This tendency seemed to be stronger for women than men.

Washington, DC - February 17, 2016 - Researchers from Maryland and New York have identified a novel herpes virus in cells taken from a bat. The work, published this week in mSphere, the American Society for Microbiology's new open access journal, could lead to better understanding of the biology of these viruses and why bats serve as hosts for a number of viruses that can potentially transfer to humans.

Eight new whip spider species have been found in the Brazilian Amazon, almost doubling the number of known charinid whip spider species in Brazil, according to a study published Feb. 17, 2016 in the open-access journal PLOS ONE by Alessandro Ponce de Leão Giupponi and Gustavo Silva de Miranda from Fundação Oswaldo Cruz, Brazil and the Center of Macroecology, Evolution and Climate at the University of Copenhagen (Denmark), respectively.

An analysis of scientific reports and comments on the health effects of a salty diet reveals a polarization between those supportive of the once-popular belief that population-wide reduction of salt intake is associated with better health and those that content it has been more hype than science. They used a citation analysis method of reviews, a little different from a traditional method, which basically just averages out other studies and attempts to control for differences.

In all, 54 percent were supportive of the hypothesis; 33 percent, not supportive; and 13 percent inconclusive, finds the article in the International Journal of Epidemiology.

The longest time anyone has spent in space is just over fourteen months. So far, astronauts have recovered surprisingly quickly, even after the longest duration spaceflights. Within a few weeks they are almost back to normal health. There are some longer term effects, on load bearing bones, which may take a couple of years to clear up, and very rarely, permanent effects on the eyes.

But what about longer periods in space than that? Their condition continually deteriorates for as long as they are in space and so far nobody has spent as long as two years in space; the record is fourteen months. So the question is still wide open for longer duration flights.

First let's look at what we know already.

LOS ALAMOS, N.M., February 16, 2015--A paper in the latest issue of the journal Nature suggests a common ancestor of apes and humans, Chororapithecus abyssinicus, evolved in Africa, not Eurasia, two million years earlier than previously thought.

"Our new research supports early divergence: 10 million years ago for the human-gorilla split and 8 million years ago for our split from chimpanzees," said Los Alamos National Laboratory geologist and senior team member Giday WoldeGabriel. "That's at least 2 million years earlier than previous estimates, which were based on genetic science that lacked fossil evidence."

Ask a biofuel researcher to name the single greatest technical barrier to cost-effective ethanol, and you're likely to receive a one-word response: lignin.

Cellulosic ethanol--fuel derived from woody plants and waste biomass--has the potential to become an affordable, renewable transportation fuel that rivals gasoline, but lignin, one of the most ubiquitous components of the plant cell wall, gets in the way.

Experts estimate that illegal cartels of businesses harm consumers to the tune of many billions of dollars annually as they secretly collude to set prices, allocate territory, and distort market competition for their own financial benefit. In a new Significance article, Carsten Crede, of the Centre for Competition Policy and the School of Economics at the University of East Anglia, outlines the pros and cons of cartel screens, which are statistical tools to help spot bad business behavior.

Crede notes that cartel screens do not definitively prove bad behavior, but they flag where authorities should take a closer look.

WASHINGTON (Feb. 16, 2016) -- Viewing graphic anti-smoking images on cigarette packs triggers activity in brain areas involved in emotion, decision-making and memory as observed via brain scans. Researchers from Georgetown University Medical Center and Truth Initiative reported their findings online this week in Addictive Behaviors Reports.

The brain scanning study, the first to be conducted in young adult smokers, suggest these images could effectively warn smokers about cigarettes' health consequences, says the study's co-lead author, Darren Mays, PhD, MPH, an assistant professor of oncology at Georgetown Lombardi Comprehensive Cancer Center in Washington, DC.