Sperm that don't swim well rank high among the main causes of infertility but these cells may get a boost from motorized "spermbots" that can deliver poor swimmers -- that are otherwise healthy -- to an egg.  

The study indicates that under the frigid weight of Barents Sea Ice sheet, which covered northern Eurasia some 22 000 years ago, significant amounts of methane may have been stored as hydrates in the ground. As the ice sheet retreated, the methane rich hydrates melted, releasing the climate gas into the ocean and atmosphere for millennia.

This finding was published last week in Nature Communications in the paper "Ice-sheet-driven methane storage and release in the Arctic".

As decision makers from around the world congregated in Paris to prepare a global climate agreement at the 21st Conference of the Parties (COP21), many discussions focused on how to reduce greenhouse gases, including ozone.

While efforts to limit ozone precursor emissions tend to focus on industrial activities and fossil fuel combustion in the United States and China, a new study suggests that future regulations may need to address the burning of forests and vegetation. The study, which was published online January 13, 2016 in the journal Nature Communications, indicates that these types of "biomass burning" may play a larger role in climate change than previously realized.

High levels of vitamin D are linked to improved fertility and reproductive success, a study of wild sheep has found.

The study, carried out on a remote Hebridean island, adds to growing evidence that vitamin D - known as the sunshine vitamin - is associated with reproductive health.

Experts hope that further studies will help to determine the relevance of the results for other mammals, including people.

CINCINNATI - Researchers have identified a molecular target and experimental treatment strategy for DNA repair defects behind Fanconi anemia - a complex genetic disorder responsible for birth anomalies, organ damage, anemia and cancer.

The findings, published Jan. 12, 2016, in Stem Cell Reports, also create a bit of molecular intrigue. It involves how cells used in the study -- which still had the Fanconi anemia (FA) DNA repair defect -- were able to recover and grow normally after targeted treatment.

January 12, 2016 -- Young children in deep poverty, whose family income is below 50 percent of the federal poverty line, fare even worse on health and development indicators than children in poverty, according to a study released by the National Center for Children in Poverty (NCCP) at Columbia University's Mailman School of Public Health. The study compared the well-being of children in deep poverty to children who are poor, but not in deep poverty, and to non-poor children.

A new study found that when temperatures get warmer, woodrats suffer a reduced ability to live on their normal diet of toxic creosote, suggesting that global warming may hurt plant-eating animals.

Ants don't get distracted by social information when on the move, only fully responding to it when at rest, a new study from the University of Bristol, UK indicates. Such sporadic monitoring of the social environment may reduce information overload and enhance the robustness of complex societies, the researchers suggest.

Edmund Hunt, a PhD student in Bristol's School of Biological Sciences, and colleagues tracked the movement patterns of lone rock ants (Temnothorax albipennis) exploring a large arena outside the nest, both when the arena was clean and when it contained chemical information (pheromones or other cues) left by previous nest-mates.

PISCATAWAY, NJ - Young people's exposure to alcohol advertisements on television could be greatly reduced if alcohol companies improved their use of so-called no-buy lists, according to a study in the January issue of the Journal of Studies on Alcohol and Drugs.

Alcohol manufacturers are self-regulated when it comes to advertising: In 2003, the industry set guidelines that limit advertising to media that have a primarily adult audience -- with at least 71.6 percent of the audience being age 21 or older.

This news release is available in French.

A gene involved in the regulation of emotions and behaviour could influence the long-term impact of violence experienced in childhood on antisocial behaviour. This is the finding of a longitudinal study carried out by a team of researchers at the Institut universitaire en santé mentale de Montréal (CIUSSS de l'Est-de-l'Île-de-Montréal) and Université de Montréal on 327 young men who live in Quebec (Quebec Longitudinal Study of Kindergarten Children), some of whom were exposed to violence as children.