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Bumble bees have discriminating palettes when it comes to their pollen meals, according to researchers at Penn State. The researchers found that bumble bees can detect the nutritional quality of pollen, and that this ability helps them selectively forage among plant species to optimize their diets.

"Populations of many bee species are in decline across the world, and poor nutrition is thought to be a major factor causing these declines," said Christina Grozinger, director of the Center for Pollinator Research, Penn State. "Our studies can help identify plant species and stocks that provide high-quality nutrition for bumble bees and potentially other bee species, which will help in the development of pollinator-friendly gardens and planting strips."

Imagine a material lighter than steel, longer-lasting than lumber and strong enough to support 120-ton locomotives.

Now imagine that material is made from milk containers, coffee cups and other plastics that we recycle.

It’s called structural plastic lumber, and the ingenious, nontoxic material was invented by Thomas Nosker, an assistant research professor in the Department of Materials Science and Engineering and principal investigator in the Center for Advanced Materials via Immiscible Composite Materials at Rutgers University. The late Richard W. Renfree, Nosker’s graduate student who later became a Rutgers professor, helped invent the revolutionary material.

Beijing and surrounding areas of China often suffer from choking smog. The Chinese government has made commitments to improving air quality and has achieved notable results in reducing emissions from the power and transportation sectors. However, new research indicates that the government could achieve dramatic air quality improvements with more attention on an overlooked source of outdoor pollution -- residential cooking and heating.

"Coal and other dirty solid fuels are frequently used in homes for cooking and heating," said Denise Mauzerall, a professor of civil and environmental engineering and public and international affairs at Princeton University. "Because these emissions are essentially uncontrolled they emit a disproportionately large amount of air pollutants which contribute substantially to smog in Beijing and surrounding regions."

La física tiene sus propias piedras de Rosetta. Son sistemas de cifrado, que se utilizan para traducir los regímenes aparentemente dispares del universo. Relacionan la matemática pura a cualquier rama de la física que usted pueda desear.

Está en la electricidad. Está en el magnetismo. Está en la mecánica de fluidos

Antarctic sea ice is constantly on the move as powerful winds blow it away from the coast and out toward the open ocean. A new study shows how that ice migration may be more important for the global ocean circulation than anyone realized.

A team of scientists used a computer model to synthesize millions of ocean and ice observations collected over six years near Antarctica, and estimated, for the first time, the influence of sea ice, glacier ice, precipitation and heating on ocean overturning circulation. Overturning circulation brings deep water and nutrients up to the surface, carries surface water down, and distributes heat and helps store carbon dioxide as it flows through the world's oceans, making it an important force in the global climate system. The scientists found that freshwater played the most powerful role in changing water density, which drives circulation, and that melting of wind-blown sea ice contributed 10 times more freshwater than melting of land-based glaciers did.