Human pluripotent stem cells, which can develop into any cell type in the body, rely heavily on glycolysis, or sugar fermentation, to drive their metabolic activities.
In contrast, mature cells in children and adults depend more on cell mitochondria to convert sugar and oxygen into carbon dioxide and water during a high energy–producing process called oxidative phosphorylation. (more…)
University of Hawai‘i at Mānoa geologist Kenneth Rubin is among the first scientists to witness exploding rock and molten lava from a deep sea volcano, seen during a 2009 expedition. He is co-author of a paper reporting that the eruption was near a tear in the Earth’s crust that is mimicking the birth of a subduction zone.
Scientists on the expedition collected boninite, a rare, chemically distinct lava that accompanies the formation of Earth’s subduction zones. (more…)
*Significant amount of carbon in land is leaking into streams and rivers, then to the atmosphere*
Rivers and streams in the United States are releasing substantially more carbon dioxide into the atmosphere than previously thought.
This according to researchers publishing their results in the current issue of the journal Nature Geoscience. (more…)
Washington, D.C. — It is difficult to measure accurately each nation’s contribution of carbon dioxide to the Earth’s atmosphere. Carbon is extracted out of the ground as coal, gas, and oil, and these fuels are often exported to other countries where they are burned to generate the energy that is used to make products. In turn, these products may be traded to still other countries where they are consumed. A team led by Carnegie’s Steven Davis, and including Ken Caldeira, tracked and quantified this supply chain of global carbon dioxide emissions. Their work will be published online by Proceedings of the National Academy of Sciences during the week of October 17. (more…)
ANN ARBOR, Mich.— North American forests appear to have a greater capacity to soak up heat-trapping carbon dioxide gas than researchers had previously anticipated.
As a result, they could help slow the pace of human-caused climate warming more than most scientists had thought, a U-M ecologist and his colleagues have concluded. (more…)
Woods Hole Oceanographic Institution (WHOI) scientists have discovered that bacterial communication could have a significant impact on the planet’s climate.
In the ocean, bacteria coalesce on tiny particles of carbon-rich detritus sinking through the depths. WHOI marine biogeochemists Laura Hmelo, Benjamin Van Mooy, and Tracy Mincer found that these bacteria send out chemical signals to discern if other bacteria are in the neighborhood. If enough of their cohorts are nearby, then bacteria en masse commence secreting enzymes that break up the carbon-containing molecules within the particles into more digestible bits. It has been suggested that coordinated expression of enzymes is very advantageous for bacteria on sinking particles, and Hmelo and her colleagues have uncovered the first proof of this in the ocean. (more…)
ANN ARBOR, Mich.— After the last ice age peaked about 18,000 years ago, levels of atmospheric carbon dioxide rose about 30 percent. Scientists believe that the additional carbon dioxide—a heat-trapping greenhouse gas—played a key role in warming the planet and melting the continental ice sheets. They have long hypothesized that the source of the gas was the deep ocean.
But a new study by a University of Michigan paleoclimatologist and two colleagues suggests that the deep ocean was not an important source of carbon during glacial times. The finding will force researchers to reassess their ideas about the fundamental mechanisms that regulate atmospheric carbon dioxide over long time scales. (more…)
Despite efforts to encourage the recycling of plastic water bottles, milk jugs and similar containers, a majority of the plastic packaging produced each year in the United States ends up in landfills, where it can take thousands of years to degrade. To address that problem with traditional polyethylene, polypropylene, Styrofoam and PET products, researchers at the Georgia Institute of Technology are working with the Plastics Environmental Council (PEC) to expand the use of chemical additives that cause such items to biodegrade in landfills.
Added during production of the plastic packaging, the compounds encourage anaerobic landfill bacteria and fungi to break down the plastic materials and convert them to biogas methane, carbon dioxide and biogenic carbon – also known as humus. These additives – simple organic substances that build on the known structures of materials that induce polymer biodegradation – don’t affect the performance of the plastics, introduce heavy metals or other toxic chemicals, or prevent the plastics from being recycled in current channels. (more…)
