An international research team has a hypothesis regarding the mystery of why the Mediterranean Sea dried up around 5.6 million years ago. The event, known as the Messinian Salinity Crisis (MSC), saw the Mediterranean become a 1.5 kilometer deep basin for around 270,000 years, and left a kilometers-deep layer of salt due to seawater evaporation.

The cause of the MSC has been the subject of speculation and debate, but now an international team of researchers

Right now, in any American hospital, about half of the patients have a prescription for an acid-reducing drug called proton-pump inhibitors (PPIs) to reduce heartburn or prevent bleeding in their stomach and gut. 

But that well-intentioned drug may actually boost their risk of dying during their hospital stay, a new study finds, by opening them up to infections that pose more risk than bleeding would. 

Researchers have identified factors that spark the formation of pluripotent cells. Their findings, published in Developmental Cell, shed light on human embryonic development and help research into cell reprogramming and assisted conception.

By Kate Gammon, Inside Science --Without risky ideas in science, the world wouldn't have new cancer treatments, an understanding of dark matter – or even the World Wide Web. But as scientific disciplines mature, scientists in them choose to go for small, incremental advances rather than risky leaps – and those choices lead to a system that's slower and more expensive than it needs to be, according to the study authors.

The problem?

Genetic sequencing of a single tumor reveals far greater genetic diversity among cancer cells than anticipated. Researchers from the University of Chicago and the Beijing Institute of Genomics estimate that the tumor, about 3.5 centimeters in diameter, contained more than 100 million distinct mutations within the coding regions of its genes--thousands of times more than expected. 

“Here’s my bet: the kids are going to win and when they do, it’s going to matter,” prophesized environmentalist Bill McKibben about fossil fuel divestment in 2013.

If so, they are going to be led by Quakers, who were among the first to officially say no to fossil fuel stocks. Though Quakers were considered anarchists in the Old World, in America they banned slave ownership way before government did and created Pennsylvania as a commonwealth without social elites, established churches, tithes, high taxes or compulsory military service. Are they thought leaders once again?

Cultural pressures to avoid anything controversial and the need to show a positive result to get the next grant have led scientists to avoid risk-taking and choose inefficient research strategies, two new University of Chicago papers conclude.

The heart of darkness is a metaphor but it is quite literal when it comes to space. Not only is matter as we know it just a fraction of what is out there, it is only a few percent. That means the rest of the universe is truly unknown. Physicists have given what we don't know terms like Dark Matter and Dark Energy and the race is on to find signatures in "near space" (within a few thousand light years of Earth by measuring electrons and gamma rays.

The CALorimetric Electron Telescope (CALET) investigation will track the trajectory of cosmic ray particles and measure their charge and energy and hopefully help to identify dark matter and fit it into standard models of the universe.

Researchers have learned more about what happened to the climate on Mars since it was a warm and watery planet billions of years ago.

The researchers announced on Thursday that NASA's MAVEN (Mars Atmosphere and Volatile Evolution) mission has determined the rate at which the Martian atmosphere currently is losing gas to space via stripping by the solar wind. Loss of gas to space appears to have been an important part of why the Martian climate went from an early, warm, wet one that might have been able to support life at the surface to the cold, dry, desert planet we see today.

The opioid addiction for more than half of female methadone clinic patients began with painkillers prescribed by doctors, according to a paper in Biology of Sex Differences.

More than half (52%) of women and a third (38%) of men reported doctor-prescribed painkillers as their first contact with opioid drugs, a family of drugs which include prescription medicines such OxyContin and codeine, as well as illicit drugs such as heroin.