In a find that sheds light on how Earth-like planets may form, astronomers this week reported finding the first evidence of small, sandy particles orbiting a newborn solar system at about the same distance as the Earth orbits the sun.

"Precisely how and when planets form is an open question," said study co-author Christopher Johns-Krull, assistant professor of physics and astronomy at Rice University. "We believe the disk-shaped clouds of dust around newly formed stars condense, forming microscopic grains of sand that eventually go on to become pebbles, boulders and whole planets."

In previous studies, astronomers have used infrared heat signals to identify microscopic dust particles around distant stars, but the method isn't precise enough to tell astronomers just how big they become, and whether the particles orbit near the star, like the Earth does the sun, or much further away at a distance more akin to Jupiter or Saturn.

Individual genes do not cause depression, but they are thought to increase the probability of an individual having a depression in the face of other accumulating risk factors, such as other genes and environmental stressors.

One gene that has been shown to increase the risk for depression in the context of multiple stressful life events is the gene for the serotonin transporter protein. This gene is responsible for making the protein that is targeted by all current drug treatments for depression.

Researchers have identified 25 genes regulating lifespan in two organisms separated by about 1.5 billion years in evolutionary change. At least 15 of those genes have very similar versions in humans, suggesting that scientists may be able to target those genes to help slow down the aging process and treat age-related conditions.

The two organisms used in this study, the single-celled budding yeast and the roundworm C. elegans, are commonly used models for aging research. Finding genes that are conserved between the two organisms is significant, researchers say, because the two species are so far apart on the evolutionary scale -- even farther apart than the tiny worms and humans. That, combined with the presence of similar human genes, is an indication that these genes could regulate human longevity as well.

Grammar is a complex human ability yet by the age of three most children can make grammatically correct sentences. Kids with a specific language impairment(SLI), however, continue to make grammatical errors, sometimes even into adulthood. As teenagers they might make errors that other children rarely make after age five; for example, when asking a question they might say “Who Joe see someone?” rather than “Who did Joe see?”.

SLI affects about seven percent of children and is a major cause of children not reaching their educational potential but it's never been clear if these children struggle to process language or just grammar.

Researchers at University College London may have some answers. They have discovered that a system in the brain for processing grammar is impaired in some children with SLI but that these children compensate with a different brain area.

There are ten key questions we have to answer this century, says a new report by the National Research Council. The questions represent where earth science stands, how it arrived at this point, and where it may be headed.

"With all the advancements over the last 20 years, we can now get a better picture of Earth by looking at it from micro- to macro-perspectives, such as discerning individual atoms in minerals or watching continents drift and mountains grow," said Donald J. DePaolo, professor of geochemistry at the University of California at Berkeley and chair of the committee that wrote the report. "To keep the field moving forward, we have to look to the past and ask deeper fundamental questions, about the origins of the Earth and life, the structure and dynamics of planets, and the connections between life and climate, for example."

Obesity is associated with clear changes in gene-networks and the dysfunction of mitochondria, say researchers at the University of Helsinki and the National Public Health Institute - worse, the impacts of these cellular changes may aggravate and work to maintain the obese state in humans

Surprisingly, the genes most drastically affected by obesity were ones involved in the breakdown of a class of amino acids known as branched-chain amino acids. These changes in the obese twins were clearly associated with pre-diabetic changes in sugar metabolism and the action of the hormone insulin.

The researchers say that, while healthy eating habits and exercise are important, genes play some role in the development of obesity, so they studied rare cases of young (25 year old) identical twins with large differences in bodyweight and saw clear changes in the function of the cellular mitochondria.