A new sensor can detect ambient levels of mercury in the atmosphere. This new highly sensitive, laser-based instrument provides scientists with a method to more accurately measure global human exposure to mercury. The measurement approach is called sequential two-photon laser induced fluorescence (2P-LIF) and uses two different laser beams to excite mercury atoms and monitor blue shifted atomic fluorescence. University of Miami Rosenstiel School Professor of Atmospheric Sciences Anthony Hynes and colleagues tested the new mobile instrument, alongside the standard instrumentation that is currently used to monitor atmospheric mercury concentrations, during the three-week Reno Atmospheric Mercury Intercomparison Experiment (RAMIX) performed in 2011 in Reno, Nevada.

An upcoming presentation at the Society for Maternal-Fetal Medicine's annual meeting argues that more midwives and a general change to the American child delivery process can reduce cesarean delivery rates - the very thing doctors were sued for not doing enough of in the 1990s.

 Primary and repeat cesarean delivery rates are now high in the U.S., with nearly one-third of women delivering by cesarean compared to 21 percent in 1995. Cesarean delivery has also associated with a higher risk of maternal complications, longer length of stay and longer postpartum recovery, but there are non-medical reasons why it is difficult to lower the rates.

In the new GSA BULLETIN, Matteo Maggi and colleagues from Italy and Brazil present a new model of the development of fractures showing a stairway trajectory, commonly occurring in finely laminated rock, such microbialites and travertines.

These fractures strongly enhance permeability by connecting several highly porous zones enveloped in tight impermeable levels. Understanding and predicting this fracture pattern geometry, distribution, and interconnection is valuable not only for locating water supplies, but also for oil, gas, and geothermal exploration.

Seafloor sediment cores reveal abrupt, extensive loss of oxygen in the ocean when ice sheets melted roughly 10,000-17,000 years ago, according to a study from the University of California, Davis. The findings provide insight into similar changes observed in the ocean today.

In the study, published in the journal PLOS ONE, researchers analyzed marine sediment cores from different world regions to document the extent to which low oxygen zones in the ocean have expanded in the past, due to climate change.

From the subarctic Pacific to the Chilean margins, they found evidence of extreme oxygen loss stretching from the upper ocean to about 3,000 meters deep. In some oceanic regions, such loss took place over a time period of 100 years or less.

Some babies seem to have a genetic predisposition to a higher risk of being born too soon, according to a paper being presented Thursday at the Society for Maternal-Fetal Medicine's annual meeting in San Diego.

The study Birth found that variants in the fetus's DNA - not the mother's - may be what triggers some early births. 

Red galaxies may be 'dying' young because they have prematurely ejected the gas they need to make new stars.  There are two main types of galaxies; 'blue' galaxies that are still actively making new stars and 'red' galaxies that have stopped growing. Most galaxies transition slowly as they run out of raw materials needed for growth over billions of years but a pilot study looking at galaxies that die young has found some might shoot out this gas early on, causing them to redden and kick the bucket prematurely.

Swedish studies show that mice that receive a supplement of the "appetite hormone" ghrelin increase their sexual activity. Whether the hormone has the same impact on humans is unknown - but if it does, the researchers may have found the key to future treatments for sex abuse.

Ghrelin is a gastrointestinal hormone that is released from the stomach, and is involved in the stimulation of our appetite by activating the brain's reward system.

Since the brain's reward system also motivates us to seek a partner and to have sex, a group of researchers at the Sahlgrenska Academy decided to investigate whether ghrelin may also affect sexual behaviors.

Confirmed effect

The answer is: yes, at least in mice.

Globe Conservation Horizon Scanning, which involves collaboration of the worldwide conservation community, focuses on identifying potential environmental problems across the planet that have not yet been noticed by society as a whole. This scanning of the environmental horizons has been conducted every year since 2010.

Although scientific findings and reports are issued - in English - based on these global scans, the limited proportion of the worldwide populace that has advanced English reading skills limits the readership of these materials. Less than one fifth of the world population speaks English; even less can read English.

For most of us, switching to a vegetarian diet might be a matter of a New Year's resolution and a fair amount of willpower, but for an entire species, it's a much more involved process -- one that evolutionary biologists have struggled to understand for a long time.

Researchers at the University of Arizona have taken a peek behind the curtain of evolution to find out what happens when an insect species dramatically changes its way of life. The processes they discovered involve never-seen-before remodeling of genes, behaviors and diet. The results, published in the Proceedings of the National Academy of Science, or PNAS, are likely to make you ponder evolutionary questions next time you find a fruit fly floating in your glass of wine.

One of nature's fascinating questions is how zebras got their stripes.

A team of life scientists led by UCLA's Brenda Larison has found at least part of the answer: The amount and intensity of striping can be best predicted by the temperature of the environment in which zebras live.

In the January cover story of the Royal Society's online journal, Open Science, the researchers make the case that the association between striping and temperature likely points to multiple benefits -- including controlling zebras' body temperature and protecting them from diseases carried by biting flies.