A group of University of Utah scientists say they developed a "molecular condom" that could help protect women against AIDS in Africa and other impoverished areas.

It's a vaginal gel that turns semisolid in the presence of semen, trapping AIDS virus particles in a microscopic mesh so they can't infect vaginal cells.

A study testing the behavior of the new gel and showing how it traps AIDS-causing HIV particles will be published online later this week in the journal Advanced Functional Materials.

The sex hormone estrogen tempers the killing activity of immune cells called cytotoxic T cells (CTLs), which are known to attack tumor cells and cells infected by viruses.

Estrogen plays a critical role in the regulation of growth and the development of cells and is also crucial for cell-type-specific gene expression in various tissues. Deregulation of this system results in breast and ovarian cancer.  The key player in this process is a cytotoxic T cell molecule known as EBAG9.

Breast and ovarian tumors are treated with drugs such as tamoxifen. Researchers suggest that this drug inhibits tumor growth by blocking the estrogen receptors of the tumor cells. However, up to now it has been unclear what effect this inhibition has on the immune system. 

Methane was discovered on Mars in 2004, meaning volcanic activity continues to generate heat below the martian surface or, if you are exceptionally kooky, that life there is generating it.

When Mars Express arrived in orbit around the red planet, Vittorio Formisano, Istituto di Fisica dello Spazio Interplanetario CNR, Rome, and the rest of the instrument team using planetary Fourier Spectrometer (PFS) began taking data and saw a puzzling signal; along with atmospheric gases such as carbon monoxide and water vapor, they saw methane.  
 

When did executions go from being functional example-setting to being more humane in method?

Annulla Linders, a University of Cincinnati sociologist, examined newspaper accounts of 19th and 20th century Ohio executions to put more 'scientific' executions in context.  

Linders used two late 19th century executions to illustrate the transition from hanging to electrocution and determined that central to the switch was the audience of executions - including journalists and physicians. 

Scientists at the University of California, Berkeley, and Lawrence Berkeley National Laboratory in the US, have performed sophisticated laser measurements to detect the subtle effects of one of nature's most elusive forces - the "weak interaction", and in the process also found the largest effect of the weak interaction ever observed in an atom.

Higher education has helped women narrow the wage gap but there is one college-related factor that has becoming increasingly important in perpetuating that gap, according to new research.

And that factor is their college major.   Women dominate the social sciences, for example, so by not moving more into hard sciences, the numbers are not normalizing across all fields.   Women at the higher levels of research and in disciplines like engineering show no modern wage gap.