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One of the hottest new materials is a class of porous solids known as metal-organic frameworks, or MOFs. These man-made materials were introduced in the 1990s, and researchers around the world are working on ways to use them as molecular sponges for applications such as hydrogen storage, carbon sequestration, or photovoltaics.

Now, a surprising discovery by scientists in Canada and Russia reveals that MOFs also exist in nature -- albeit in the form of rare minerals found so far only in Siberian coal mines.

The finding, published in the journal Science Advances, "completely changes the normal view of these highly popular materials as solely artificial, 'designer' solids," says senior author Tomislav FrišÄić, an associate professor of chemistry at McGill University in Montreal. "This raises the possibility that there might be other, more abundant, MOF minerals out there."

The end of last month brought big news in the battle to rein in climate change. The U.S. Environmental Protection Agency announced that greenhouse gas (GHG) emissions from airplanes pose a threat to human health and the environment and therefore are subject to regulation under the Clean Air Act.

The Act was originally passed in 1970 to combat air pollution in the form of airborne lead and mercury, sulfur and nitrogen oxides, carbon monoxide, particulates, and ground-level ozone — to name a few. It was updated in 1990 to include emissions that threaten the ozone layer, and again in 2009 to deal with emissions known to contribute to climate change.

This announcement now clears the way for the EPA to develop rules to regulate aircraft emissions, much as the agency has done for emissions from cars and trucks. Aircraft are responsible for roughly 12 percent of all U.S. transportation-related greenhouse gas emissions, or a little over 3 percent of all U.S. GHG emissions.

While the human race will always leave its carbon footprint on the Earth, it must continue to find ways to lessen the impact of its fossil fuel consumption.

"Carbon capture" technologies - chemically trapping carbon dioxide before it is released into the atmosphere - is one approach. In a recent study, Cornell University researchers disclose a novel method for capturing the greenhouse gas and converting it to a useful product - while producing electrical energy.

Lynden Archer, the James A. Friend Family Distinguished Professor of Engineering, and doctoral student Wajdi Al Sadat have developed an oxygen-assisted aluminum/carbon dioxide power cell that uses electrochemical reactions to both sequester the carbon dioxide and produce electricity.

Cientos de millones de aves mueren en colisiones con ventanas cada año sólo en los EE.UU., y aunque los edificios altos tienden a ser los mayores culpables individuales, la gran cantidad de viviendas suburbanas en todo el continente significan que, incluso pocas muertes por casa, dan una gran pérdida de aves. Un nuevo estudio publicado en The Condor: Aplicaciones Ornitológicas, examina los factores que afectan las tasas de colisión de las ventanas en las casas y muestra que los jardines que son más atractivos para las aves son también los sitios con más colisiones.

Trabajando con los propietarios de casas de Alberta, quienes contribuyeron colectivamente con datos de colisión de más de 34.000 días, Justine Kummer de la Universidad de Alberta y sus colegas encontraron que la presencia de un alimentador de aves, ya sea una casa que estaba en una zona urbana o rural y la altura de la vegetación en el patio fueron los predictores más importantes de colisiones. De 421 especies de aves de Alberta, 53 estaban incluidas en los datos, la mayoría de especies urbanas comunes.

Researchers in Abu Dhabi are testing a pilot device that can store solar energy in sand to improve the efficiency of power plants and provide energy at night.

The technology, developed at the Masdar Institute of Science and Technology, uses gravity to drain sand from a higher basin into a lower one, heating up the sand grains with solar power during the transition. In the lower basin, the energy can be stored and withdrawn at low cost to provide extra energy if needed, for example during peak hours and at night-time.

"Two pilot models of the system have been tested in an effort to prove its efficiency and applicability on a large scale in big projects,” says Nicolas Calvet, an assistant professor at the Masdar institute’s department of mechanical engineering.