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.