Tag Archives: nitrogen

The Helix Nebula: Bigger in Death than Life

A dying star is refusing to go quietly into the night, as seen in this combined infrared and ultraviolet view from NASA’s Spitzer Space Telescope and the Galaxy Evolution Explorer (GALEX), which NASA has lent to the California Institute of Technology in Pasadena. In death, the star’s dusty outer layers are unraveling into space, glowing from the intense ultraviolet radiation being pumped out by the hot stellar core.

This object, called the Helix nebula, lies 650 light-years away in the constellation of Aquarius. Also known by the catalog number NGC 7293, it is a typical example of a class of objects called planetary nebulae. Discovered in the 18th century, these cosmic works of art were erroneously named for their resemblance to gas-giant planets. (more…)

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Water in a Changing World

Experimental watershed provides new insights, rich educational experience

Six years and about 4,000 water samples later, an outdoor experimental watershed laboratory established by University of Delaware faculty members Shreeram Inamdar and Delphis Levia at Fair Hill, Md., is now producing valuable data and novel insights into how water and chemicals move through the forest canopy, soils and watersheds, and how future climate change may impact or alter such responses.

Inamdar, associate professor in the Department of Plant and Soil Sciences, has investigated the role of soils, streams, and watersheds in leaching water and nutrients, while Levia, professor in the Department of Geography, has studied the interactions of atmosphere and the forest canopy in leaching water and nutrients. Together, they have provided a complete picture of watershed hydrology and biogeochemistry. (more…)

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New Projection Shows Global Food Demand Doubling by 2050

*Increasing yield in poorer countries could decrease adverse environmental effects*

Global food demand could double by 2050, according to a new projection reported this week in the journal Proceedings of the National Academy of Sciences (PNAS).

The analysis also shows that the world faces major environmental challenges unless agricultural practices change.

Scientists David Tilman and Jason Hill of the University of Minnesota (UMN) and colleagues found that producing the amount of food needed could significantly increase levels of carbon dioxide and nitrogen in the environment, and may cause the extinction of numerous species. (more…)

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A Tailored Pair of Genes

*For ancient plants, two genes were definitely better than one*

In the wake of the disaster that killed the dinosaurs, the ancestors of today’s crop plants reinvented themselves.

They doubled their genomes, and in that single act set the stage for feeding the world 60 million years later.

In a study published in the Nov. 16 issue of the journal Nature, researchers from the University of Minnesota and other institutions recount how sequencing the genome of a model, alfalfa-like legume revealed the monumental benefits that flowed when the ancestor of legumes acquired an extra copy of every gene. (more…)

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NSF Announces Major Awards for Biodiversity Research, WHOI Scientists Selected

The 1977 discovery of deep-sea hydrothermal vent ecosystems that obtain energy through chemosynthesis rather than photosynthesis greatly expanded the perception of life on Earth. However, an understanding of their underlying microbiology and biogeochemistry still remains elusive.

A newly funded project, one of several major awards announced by the National Science Foundation’s (NSF) Dimensions in Biodiversity research program, stands to change that through a multi-disciplinary, international collaborative research effort led by Associate Scientist Stefan Sievert of the Woods Hole Oceanographic Institution. (more…)

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WHOI Study Reports Microbes Consumed Oil in Gulf Slick at Unexpected Rates

More than a year after the largest oil spill in history, perhaps the dominant lingering question about the Deepwater Horizon spill is, “What happened to the oil?” Now, in the first published study to explain the role of microbes in breaking down the oil slick on the surface of the Gulf of Mexico, Woods Hole Oceanographic Institution (WHOI) researchers have come up with answers that represent both surprisingly good news and a head-scratching mystery.

In research scheduled to be published in the Aug. 2 online edition of Environmental Research Letters, the WHOI team studied samples from the surface oil slick and surrounding Gulf waters. They found that bacterial microbes inside the slick degraded the oil at a rate five times faster than microbes outside the slick—accounting in large part for the disappearance of the slick some three weeks after Deepwater Horizon’s Macondo well was shut off. (more…)

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‘Hot-Bunking’ Bacterium Recycles Iron to Boost Ocean Metabolism

In the vast ocean where an essential nutrient—iron—is scarce, a marine bacterium that launches the ocean food web survives by using a remarkable biochemical trick: It recycles iron.

By day, it uses iron in enzymes for photosynthesis to make carbohydrates; then by night, it appears to reuse the same iron in different enzymes to produce organic nitrogen for proteins. (more…)

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