It is easy to observe that many networks naturally divide into communities or modules, where links within modules are stronger and denser than those across modules – like the way people from the same age group tend to interact more with each other than with people from different age groups. It is widely believed that networks within cells are modular in much the same way. Drs Zhi Wang and Jianzhi Zhang, from the University of Michigan, now investigate these modular properties and conclude that they may be only a random byproduct of evolution, and not functional at all.

NASA and Columbia University Earth Institute research finds that human-made greenhouse gases have brought the Earth’s climate close to critical tipping points, with potentially dangerous consequences for the planet.

From a combination of climate models, satellite data, and paleoclimate records the scientists conclude that the West Antarctic ice sheet, Arctic ice cover, and regions providing fresh water sources and species habitat are under threat from continued global warming.

Three new drugs are predicted to help transform the long-term prognosis for people with the AIDS virus, says an editorial in BMJ, which points towards highly promising results from trials of three new drugs.

HIV patients in “deep salvage” – meaning those people who have developed multidrug resistant HIV that does not respond to drug combination therapy – could benefit the most.

Researchers exploring the notion that certain nutrients might protect against pancreatic cancer found that lean individuals who got most of these nutrients from food were protected against developing cancer. The study also suggests this protective effect does not hold true if the nutrients come from vitamin supplements.

Investigators combined data from four large studies and found that people who were at or below normal body weight decreased their risk for developing pancreatic cancer if they took in high levels of vitamin B6, vitamin B12, and folate from food. The study determined that their risk was 81 percent, 73 percent, and 59 percent lower, vitamin B6, vitamin B12, and folate respectively, compared with participants who did not eat as much of these nutrients or who weighed more.

The majority of doctors in North Carolina do not probe for signs of postpartum depression in new mothers, according to a survey conducted by researchers at the University of North Carolina at Chapel Hill.

Of the 228 physicians responding to the survey who said they had seen women for postpartum visits in the previous three months, 79 percent said they were unlikely to formally screen the patients for depression. An estimated 13 percent of new mothers are affected by postpartum depression.

Small changes in agricultural and sanitation practices may eliminate the spread of a disease that affects some 200 million people living in developing nations around the world.

Researchers working in remote farming villages in western China report that providing medicine to infected people and animals, along with modifying irrigation and waste treatment practices could reduce, or even eliminate, the long-term transmission of schistosomiasis.

Schistosomiasis is a disease that can affect the liver, the gastrointestinal tract or the bladder.