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. 

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.

One experimental result doesn't mean much in science. To truly know whether a result is valid, it needs to be reproduced in the same way over and over again. Yet research that may not be reproduced often finds its way into well-regarded journals, due to limited resources, human error or, rarely, outright fraud.

Unreplicable research is especially problematic for drug trials and other clinical research. A recent estimate put the costs associated with irreproducible preclinical research at $28 billion a year in the United States. Short of spending money to run the published experiment again, no mechanisms exist to quickly identify findings that are unlikely to be replicated.