Bile acid derivatives can turn on the vitamin D receptor (VDR) without causing excess calcium buildup, researchers report, a finding that could lead to vitamin D therapies for conditions beyond just bone and skin disorders.

While calcium balance may be the most well-known role of vitamin D, this molecule –through VDR binding– regulates many functions including immunity and cell growth and thus has diverse therapeutic potential. However, while vitamin D-based drugs are effective against some cancers and microbial infections, the risk of excess blood calcium has limited their clinical use.

Recently, mathematician Daniel J. Madden and retired physicist Lee W. Jacobi found solutions to a puzzle that has been around for centuries - an infinite number of solutions for a puzzle known as 'Euler’s Equation of degree four.'

The equation is part of a branch of mathematics called number theory. Number theory deals with the properties of numbers and the way they relate to each other. It is filled with problems that can be likened to numerical puzzles.

“It’s like a puzzle: can you find four fourth powers that add up to another fourth power" Trying to answer that question is difficult because it is highly unlikely that someone would sit down and accidentally stumble upon something like that,” said Madden, an associate professor of mathematics at The University of Arizona in Tucson.

There are a number of interconnected factors that lead to the success or failure of any business so it is usually considered an impossible task to predict whether a company will sink or swim numerically but researchers in Taiwan using the principles of evolutionary biology say they have devised an approach to spotting when a company is likely to fail.

Ping-Chen Lin of the National Kaohsiung University of Applied Sciences in Kaohsiung and Jiah-Shing Chen of the National Central University, Jhongli, in Taiwan, also explain how their metric of the financial status of any company can be of interest not only to its owners and employees but to a range of creditors, stockholders, banks, and individual investors.

Writing in the Journal of the American Medical Association, a medical team from the University of Leicester say they have established a predictor for pregnant women who may have miscarriages and those who won’t.

The researchers measured the levels of a naturally occurring ‘cannabis’ (an endocannabinoid) known as anandamide in women who presented with a threatened miscarriage (bleeding in early pregnancy with a viable baby) and found that those who at the time of the test had significantly higher levels of anandamide subsequently miscarried.

A new mathematical object was revealed yesterday during a lecture at the American Institute of Mathematics (AIM). Two researchers from the University of Bristol exhibited the first example of a third degree transcendental L-function. These L-functions encode deep underlying connections between many different areas of mathematics.

The news caused excitement at the AIM workshop attended by 25 of the world's leading analytic number theorists. The work is a joint project between Ce Bian and his adviser, Andrew Booker. Booker commented that, "This work was made possible by a combination of theoretical advances and the power of modern computers."

Fifty years have passed since the United States Department of Agriculture and the U.S. Army invented DEET to protect soldiers from disease-transmitting insects and in the process made civilian life outdoors nicer as well.

Despite its effectiveness, and decades of research, scientists never knew precisely how it worked.

By pinpointing DEET's molecular target in insects, researchers at Rockefeller University have shown that DEET acts like a 'chemical cloak', masking human odors that blood-feeding insects find attractive. This research makes it possible to improve the repellent properties of DEET and also make it a safer chemical.