A new study published in the Spanish Journal of Psychology indicates that in the West women experience much more guilt than men, and the primary reason is not that women feel too much guilt, but rather that many males feel too little. The authors say more needs to be done to "reduce the trend towards anxious-aggressive guilt among women and to strengthen interpersonal sensitivity among men."

Scientists from Oregon State University and the Oregon Department of Geology and Mineral Industries say a major increase in maximum ocean wave heights off the Pacific Northwest in recent decades has forced scientists to re-evaluate how high a "100-year event" might be, and raises special concerns about flooding, coastal erosion and structural damage.

The new assessment, published in the journal Coastal Engineering, concludes that the highest waves may be as much as 46 feet, up from estimates of only 33 feet that were made as recently as 1996, and a 40 percent increase. December and January are the months such waves are most likely to occur, although summer waves are also significantly higher.

Contrary to the claims of most paleontologists, researchers from University of Kansas and Northeastern University in China say that bird flight evolved up in the trees, and  flight tests of a model of the four-winged gliding raptor called microraptor lend credence to their theory.

"The controversy was that these animals couldn't spread their hind-wings to glide," said Burnham. "But we've been able to articulate the bones in their hip socket to show that they could fly." The new flight model created by Martin and Burnham comes directly from a skeleton composed of casts of the original bones of a microraptor and the preserved impressions of feathers from specimens in Chinese museums.

A comparison of two popular weight loss methods demonstrates that both are equally effective at helping people lose significant amounts of weight. But the low-carbohydrate diet proved better at lowering blood pressure than the weight-loss drug orlistat, according to a new study in the Archives of Internal Medicine.

Studies had already indicated that a low-carbohydrate diet and prescription-strength orlistat combined with a low-fat diet are effective weight loss therapies. But the two common strategies had not been compared to each other, an important omission now that orlistat is available over-the-counter. In addition, few studies provide data on these treatments for overweight patients with chronic health issues.

A new study conducted by University of Virginia psychologists suggests that well-adapted youth with positive friendships will use social networking sites like facebook and myspace to enhance the positive relationships they already have. The study also indicates, however, that teens who have behavioral problems and difficulty making friends, or who are depressed, may be more inclined to use social media in negative and sometimes aggressive ways, or not to use such sites at all.

The study appears in the January issue of Developmental Psychology.

 The authors of a new study in Energy&Fuels say they have developed an advanced "closed-loop control" approach for preventing diesel engines from emitting greater amounts of smog-causing nitrogen oxides when running on biodiesel fuels.

The new technique uses advanced models to self-adjust engine settings based on feedback from sensors. Software algorithms use data from the sensors to determine the fuel blend being combusted. If the fuel is changed, the system identifies the new fuel and makes critical adjustments to fuel-injection timing, the air-to-fuel ratio and how much exhaust is rerouted into the cylinders.