BBC NEWS | Science & Environment | Spider sex violent but effective

BBC NEWS | Science & Environment | Spider sex violent but effective: "A violent but evolutionarily effective mating strategy has been spotted in spiders from Israel.

Males of the aptly-named Harpactea sadistica species pierce the abdomen of females, fertilising their eggs directly in the ovaries.

The so-called traumatic insemination gives the first male to inseminate a reproductive advantage by bypassing structures in the females' genitalia."

Brown Fat Identified as Heat-Yielding Cells in Humans - NYTimes.com

Brown Fat Identified as Heat-Yielding Cells in Humans - NYTimes.com: "For more than 30 years, scientists have been intrigued by brown fat, a cell that acts like a furnace, consuming calories and generating heat. Rodents, unable to shiver effectively to keep warm, use brown fat instead. So do human infants, who do not shiver very well. But it was generally believed that humans lose brown fat after infancy, no longer needing it once the shivering response kicks in.

That belief, three groups of researchers report, is wrong.

Their papers, appearing Thursday in The New England Journal of Medicine, indicate that nearly every adult has little blobs of brown fat that can burn huge numbers of calories when activated by the cold, as when sitting in a chilly room that is between 61 and 66 degrees."

Science News Examiner: New discovery may end transplant rejection

Science News Examiner: New discovery may end transplant rejection: "Professor Jonathan Sprent and Dr Kylie Webster from Sydney's Garvan Institute of Medical Research focused on a different type of T cells – known as regulatory T cells (Treg) – in this study. Tregs are capable of quieting the immune system, stopping the killer T cells from seeking out and attacking foreign objects. Usually, these cells live in basic equilibrium, allowing the killer T cells to destroy what needs to be destroyed, but stopping them once the infection is over. The idea was to boost the number of Tregs in the system, quieting the killer T cells for a period of time sufficient for the body to accept the new tissue. After that point, the immune system would return to normal activity.

Using a complex that contained a molecule known as interleukin-2, a molecule that promotes T cell proliferation, the researchers radically increased the number of Tregs in healthy mice before performing the transplants, effectively quieting the killer T cells. Webster explained what followed after the transplant: 'The numbers of T regulatory cells dropped over time, and the immune systems returned to normal in about two weeks. By that time 80% of the mice had accepted the grafts of insulin producing cells as their own. This acceptance rate is very high for transplantation, with mice normally rejecting grafts within 2-3 weeks. A graft is considered accepted if it's tolerated after 100 days. We took some mice out to 200-300 days, and not one of them rejected.' [EurekAlert]"

PLoS Biology - A Computational Framework for Ultrastructural Mapping of Neural Circuitry

PLoS Biology - A Computational Framework for Ultrastructural Mapping of Neural Circuitry: "Building an accurate neural network diagram of the vertebrate nervous system is a major challenge in neuroscience. Diverse groups of neurons that function together form complex patterns of connections often spanning large regions of brain tissue, with uncertain borders. Although serial-section transmission electron microscopy remains the optimal tool for fine anatomical analyses, the time and cost of the undertaking has been prohibitive. We have assembled a complete framework for ultrastructural mapping using conventional transmission electron microscopy that tremendously accelerates image analysis."

Op-Ed Columnist - The End of Philosophy - NYTimes.com

Op-Ed Columnist - The End of Philosophy - NYTimes.com: "The first nice thing about this evolutionary approach to morality is that it emphasizes the social nature of moral intuition. People are not discrete units coolly formulating moral arguments. They link themselves together into communities and networks of mutual influence.

The second nice thing is that it entails a warmer view of human nature. Evolution is always about competition, but for humans, as Darwin speculated, competition among groups has turned us into pretty cooperative, empathetic and altruistic creatures — at least within our families, groups and sometimes nations.

The third nice thing is that it explains the haphazard way most of us lead our lives without destroying dignity and choice. Moral intuitions have primacy, Haidt argues, but they are not dictators. There are times, often the most important moments in our lives, when in fact we do use reason to override moral intuitions, and often those reasons — along with new intuitions — come from our friends."