California's coastal fog is decreasing significantly and may endanger redwood trees along the coast dependent on cool, humid summers, according to a new study to be published in PNAS. It is unclear whether this is part of a natural cycle of the result of human activity, but the change could affect the entire redwood ecosystem.

The results came from analysis of new records recently made available by the National Climate Data Center. The U.S. Surface Airways data come from airports around the country, which have recorded for more than 60 years hourly information such as cloud cover (cloud ceiling height), visibility, wind and temperature.

Human cells contain 46 strands of DNA that code for all our genes. Certain chemicals and UV light can break these strands into pieces, a process that typically leads to cell death or diseases such as cancer if the damage is not repaired quickly. But new research, published in PNAS, shows for the first time that stem cells will intentionally cut and then repair their own DNA as a mechanism of activating genes that promote the development of new tissues.

The discovery could help researchers develop better ways to activate stem cells, so that they can produce new tissues for therapeutic purposes. It also suggests that DNA mutations, which can contribute to a variety of diseases, may initially occur as a result of a normal cellular process.

Researchers from the University of Illinois say they know how to exploit an unusual chemical reaction mechanism that allows malaria parasites and many disease-causing bacteria to survive. The findings, detailed in PNAS, could eventually lead to new anti-malarial and antibacterial drugs.

The new study focused on an essential chemical pathway that occurs in malaria parasites and in most bacteria but not in humans or other animals, making it an ideal drug target. Several teams of researchers have spent nearly a decade trying to understand an important player in this cascade of chemical reactions, an enzyme known as IspH. This enzyme promotes the synthesis of a class of compounds, called isoprenoids, which are essential to life.

Infants averaging six months of age who exhibited positional plagiocephaly (flat head syndrome) had lower scores than typical infants in observational tests used to evaluate cognitive and motor development, according to a new study in Pediatrics. Positional or deformational plagiocephaly may occur when external forces shape an infant's skull while it is still soft and malleable, such as extended time spent lying on a hard surface or in one position. Researchers say the findings suggest that babies with plagiocephaly should be screened early in life for possible motor and cognitive delays.

 A new study of  most of the world's tropical land area indicates that urbanization and globalized agricultural trade have become the primary drivers of tropical deforestation, in stark contrast to the assumptions of some scientists that fast-growing urbanization and the efficiencies of global trade might eventually slow or reverse tropical deforestation. The new study appeared recently in Nature Geoscience.

Deforestation has been a rising concern in recent decades, especially with the recognition that it may exacerbate climate change. Studies in the late 20th century generally matched it with growing rural populations, as new roads were built into forests and land was cleared for subsistence agriculture.

It seems that everything except the causes of childhood obesity receive blame for childhood obesity. While common sense and plenty of research indicate that parents and social setting are the primary influences on children's eating habits, the effort to pin the problem on food manufactures never ends. Recently, the authors of a study in Pediatrics continued the charade by suggesting that product placement in movies may bear some of the responsibility for the expanding waistlines of America's Children.