Astronomers have discovered a star that may have been among the second generation of stars to form after the Big Bang.

Located in the dwarf galaxy Sculptor some 290,000 light-years away, S1020549 has a remarkably similar chemical make-up to the Milky Way's oldest stars. Its presence supports the theory that our galaxy underwent a "cannibal" phase, growing to its current size by swallowing dwarf galaxies and other galactic building blocks. The discovery of the new star is detailed in Nature.

Dwarf galaxies are small galaxies with just a few billion stars, compared to hundreds of billions in the Milky Way. In the "bottom-up model" of galaxy formation, large galaxies attained their size over billions of years by absorbing their smaller neighbors.

It may seem safe to assume that happy people are trusting people, but a new study in the Journal of Personality and Social Psychology suggests that, in some instances, people may actually be less trusting of others when they are in a pleasant mood. According to the research, people in a pleasant mood only tend to be trusting if they have a good reason to be.

If you are predisposed to trust a stranger because he belongs to the same club as you, for example, a happy mood makes you even more likely to trust him. But if you are predisposed to not trust him, a positive mood will make you even less trusting than normal.

New policies that eliminate sugary beverages and junk foods from schools may help slow childhood obesity, but the effects of such policies are unclear, according to a study in Health Affairs that compared BMI trends in California in the years preceding the enactment of such legislation with the years following enactment.

Between 2003 and 2005, California Governor Arnold Schwarzenegger signed SB 677, SB 965 and SB 12 into law, a set of statewide policies to eliminate sodas and other highly sweetened beverages and restrict the sale of junk foods in all of California's public schools. Although many other states subsequently enacted similar standards, potential effects on childhood obesity were uncertain.

Frequent secondhand smoke exposure among 13-year-olds is associated with an increased risk of future blood vessel hardening and greater risks of other heart disease factors, according to new research published in Circulation: Cardiovascular Quality and Outcomes. The authors of the study say the findings indicate that children must be provided a completely smoke-free environment.  

The study of 494 children showed that those with higher levels of exposure to secondhand smoke from ages 8 to 13 had, by age 13, significantly increased blood vessel wall thickness and functioning problems, both of which are precursors to arterial structural changes and hardening.

Researchers have successfully reconstructed 3-D hand motions from brain signals recorded in a non-invasive way, according to a study in The Journal of Neuroscience. The findings could help improve existing EEG-based systems designed to allow movement-impaired people to control a computer cursor with just their thoughts.

Previously researchers have used non-portable and invasive methods that place sensors inside the brain to reconstruct hand motions. In this study, neuroscientists placed an array of sensors on the scalps of five participants to record their brains' electrical activity, using a process called electroencephalography, or EEG.

Physical fitness is associated with improved academic performance in young people, according to a study of fifth grade students presented at the American Heart Association's 2010 Conference on Nutrition, Physical Activity and Metabolism. Many people have suggested that such a relationship exists between academic performance and physical fitness, but until now researchers say there was not enough evidence to define the nature of the relationship.