University of Utah biologists genetically manipulated nematode worms so the animals were attracted to worms of the same sex – part of a study that shows sexual orientation is wired in the creatures’ brains.

“They look like girls, but act and think like boys,” says Jamie White, a postdoctoral researcher and first author of the new study. “The [same-sex attraction] behavior is part of the nervous system.”

The study was published Thursday, Oct.

Nearly a third of the world’s 6,000 amphibian species are threatened with extinction and more than 120 species have already vanished from the planet.

Across the globe, conservation organisations and professionals are mobilising efforts to help save as many of these species as possible.

A brightly coloured tropical frog under threat of extinction is the focus of a new research project hoping to better understand how environment and diet influence its development and behavior.

Credit: University of Manchester

The shortage of islet cells limits the development of islet transplantation. One new approach was reported in the October 21 issue of the World Journal of Gastroenterology because of its great significance in enhancing the output of islet cells.

The article describes the differentiation of rat pancreatic ductal epithelial cells into insulin-producing cells by the transfection of PDX-1. In recent years, though great efforts have been made to differentiate embryonic stem cells, pancreatic ductal epithelial multipotent progenitor cells and bone marrow stem cells into islet cells, the process of cell differentiation and growth is long. Moreover, the amount of islet cells of differentiation, and the insulin released by islets, is not enough to meet the clinical needs.

The greatest mass extinction in Earth’s history also may have been one of the slowest, according to a study that casts further doubt on the extinction-by-meteor theory.

Creeping environmental stress fueled by volcanic eruptions and global warming was the likely cause of the Great Dying 250 million years ago, said USC doctoral student Catherine Powers.

Writing in the November issue of the journal Geology, Powers and her adviser David Bottjer, professor of earth sciences at USC, describe a slow decline in the diversity of some common marine organisms.

...and quite frankly I am pretty pissed off that his lectures have been cancelled. James Watson, Nobel Prize winner and cofounder of the structure of DNA told the Times of London that "there is no firm reason to anticipate that the intellectual capacities of peoples geographically separated in their evolution should prove to have evolved identically." So guess what? Most venues hosting Watson have decided to cancel his forthcoming public engagement talks.

More than 250 million women worldwide smoke tobacco. Compared to men, women have a greater risk of smoking-related diseases, and also have more difficulty quitting. A new study, the first of its kind, has found that cigarette smoking and having a family history of alcoholism have different effects on sweet-taste perception and food cravings.

“Tobacco is one of the most heavily used addictive drugs,” said M. Yanina Pepino, a researcher at the Monell Chemical Senses Center in Philadelphia and corresponding author for the study, “leading to an increased risk of lung and heart diseases and a variety of cancers.” In fact, lung cancer has surpassed breast cancer as the leading cause of death among US women, she added.

Severely restricting calories leads to a longer life, according to research in the October issue of Journals of Gerontology Series A: Biological Sciences and Medical Sciences.

The study says such a diet can also maintain physical fitness into advanced age, slowing the seemingly inevitable progression to physical disability and loss of independence.

Using a rat model of life-time caloric restriction, they showed that the diet reduces the amount of visceral fat, which expresses inflammatory factors that in humans cause chronic disease and a decline in physical performance and vitality across the lifespan.

Before political science existed as a discipline it was assumed all countries wanted the same thing; land and security. The Industrial Revolution brought a new focus on strategic resources.

In the late 1800s America was already producing more strategic resources than anyone and in World War 2 the USA asserted its industrial might geopolitically. In the post-World War Two era the American focus as a superpower was on ideology and trade.

Since that time, the recurring question has been 'who's next?' Rome fell from power, as did Mongolia and Great Britain. America would fall too, it was said. Some country would replace it.

Thousands of high school students are currently deliberating over which university to attend next year. But which are the best? A study published in the open access journal BMC Medicine warns against using international rankings of universities to answer this question. They are misleading and should be abandoned, the study concludes.

The study focuses on the published 2006 rankings of the Times Higher Education Supplement "World University Rankings" and the Shanghai Jiao Tong University "Academic Ranking of World Universities".

A topic often left out of discussions about the promise of personalized medicine that science and society offers for the future is whether or not ordinary people want that extra responsibility. Does everyone want to know if they are susceptible to certain diseases?

A two-day showcase called Genomics and Society: Today’s Answers, Tomorrow’s Questions – is taking place in London on Thursday 25 and Friday 26 October 2007. This gathering brings together policymakers, researchers and natural scientists with what is becoming the world’s largest concentration of social scientific research in this field - the ESRC Genomics Network (EGN).