Human embryonic stem cells (hESCs) hold great promise for benefiting degenerative diseases, and do so by invoking multiple mechanisms. Such cells can be grown in a manner compatible with clinical use (i.e., without animal feeder layers) and even without the need for immunosuppression. These were a few of a number of conclusions arrived at by an international collaboration led by Evan Y. Snyder, M.D., Ph.D., and spearheaded by a member of his lab, Jean-Pyo Lee, Ph.D., of the Burnham Institute for Medical Research ("Burnham"). The study, to be published in Nature Medicine, will be made available by advanced publication at the journal's website on March 11, 2007.

The "raging hormones" of puberty are known to produce mood swings and stress for most teenagers, making it difficult to cope with this period of life. Until now, the specific causes of pubertal anxiety have not been identified, making it harder to understand and treat adolescent angst.

In the current edition of the journal Nature Neuroscience, researchers led by Sheryl S. Smith, PhD, professor of physiology and pharmacology at SUNY Downstate Medical Center, report findings demonstrating that a hormone normally released in response to stress, THP, actually reverses its effect at puberty, when it increases anxiety.

This hormone normally acts like a tranquilizer, acting at sites in the brain that "calm" brain activity.

Each year, malaria results in more than a million deaths. Controlling this disease involves understanding its transmission, and understanding its transmission means understanding its basic reproductive number, R0. For all infectious disease, R0 describes the most important aspects of transmission as it is the expected number of hosts that can trace their infection directly back to a single host after one disease generation. For vector-borne diseases, such as malaria, R0 is given by a classic formula. In a new study published in PLoS Biology, David Smith and colleagues demonstrate that estimates of R0 range from around one to over 3,000, providing much higher estimates than previously thought, with serious implications for the control of the disease.

Understanding the origin and behavior of the magnetic fields of planets and stars is the goal of research being carried out by many teams from all over the world. The VKS1 collaboration (CEA2, CNRS3,4, Ecole normale supérieure in Lyon3, Ecole normale supérieure in Paris4) has succeeded in creating in the laboratory a magnetic field in a highly turbulent flow of liquid sodium. Although the extreme conditions specific to astrophysical and geophysical environments cannot all be reproduced in the laboratory, the magnetic field observed shows remarkable similarities with magnetic fields observed in the cosmos. The findings represent a significant advance in the understanding of the mechanisms at work in the formation of natural magnetic fields.

A decade-long mystery has been solved using data from ESA's X-ray observatory XMM-Newton. The brightest member of the so-called 'magnificent seven' has been found to pulsate with a period of seven seconds.

The discovery casts some doubt on the recent interpretation that this object is a highly exotic celestial object known as a quark star.

Severe climate changes during the last ice-age could have been caused by random chaotic variations on Earth and not governed by external periodic influences from the Sun. This has been shown in new calculations by a researcher at the Niels Bohr Institute, Copenhagen University.