Tag Archives: model

New Research Underscores Vulnerability of Wildlife in Low-Lying Hawaiian Islands

By Guest PostDecember 7, 2012Environment, Natureblack footed albatross, bonin petrel, climate change, crystal m krause, curt storlazzi, global sea level, habitat loss, island biodiversity, jamie carter, karen n courtot, kure atoll, laysan albatross, laysan island, low lying island, michelle h reynolds, migratory wildlife species, model, multifaceted assessment, national wildlife refuge, northwestern hawaiian islands, nwhi, over fished ocean, pacific ocean, paul berkowitz, prediction, sea-level rise, topographic data, trend, tropical seabird rookery, U.S. Geological Survey, wave action, World Heritage Site

HONOLULU, Hawaii — If current climate change trends continue, rising sea levels may inundate low-lying islands across the globe, placing island biodiversity at risk. A new U.S. Geological Survey scientific publication describes the first combined simulations of the effects of sea-level rise and wave action in the Northwestern Hawaiian Islands, offering the most detailed and multifaceted assessment available of how island biodiversity may be affected by climate change.

The publication, “Predicting Sea-Level Rise Vulnerability of Terrestrial Habitat and Wildlife of the Northwestern Hawaiian Islands,” by Michelle H. Reynolds, Paul Berkowitz, Karen N. Courtot, Crystal M. Krause, Jamie Carter, and Curt Storlazzi is available online. (more…)

Not-So-Permanent Permafrost

By Guest PostOctober 26, 2012Environmentalaska, arctic permafrost, atmosphere, carbon, chemical cycles, climate change, climate prediction, climate warming, director, earth, ecosystems, Environment, fairbanks, frozen ground, gelisols, geological survey, jennifer harden, lakes, marcia mcnutt, mikhail kanevsiy, model, nitrogen, organic matter, peaty, rivers, scenarios, scientist, soil scientist, university, US, usgs, warmer planet, warming phenomenon, water resources

MENLO PARK, Calif. — As much as 44 billion tons of nitrogen and 850 billion tons of carbon stored in arctic permafrost, or frozen ground, could be released into the environment as the region begins to thaw over the next century as a result of a warmer planet according to a new study led by the U.S. Geological Survey. This nitrogen and carbon are likely to impact ecosystems, the atmosphere, and water resources including rivers and lakes. For context, this is roughly the amount of carbon stored in the atmosphere today.

The release of carbon and nitrogen in permafrost could exacerbate the warming phenomenon and will impact water systems on land and offshore according to USGS scientists and their domestic and international collaborators. The previously unpublished nitrogen figure is useful for scientists who are making climate predictions with computer climate models, while the carbon estimate is consistent and gives more credence to other scientific studies with similar carbon estimates. (more…)

Bounce, Skid, Wobble: How Huygens Landed on Titan

By Guest PostOctober 11, 2012Science17th century, analysis, astronomer, cassini spacecraft, christiaan huygens, direction, dutch, earth, erich karkoschka, european, evaporate, friction, hazy atmosphere, horizon, huygens data, huygens impact, huygens probe, institute, lower atmosphere, max planck, methane, model, moon, moon surface, motion, mud like, NASA, nicolas altobelli, organic aerosols, ralph lorenz, saturn, space agency, splat, stefan schroder, substance, titan, titan atmosphere, undisturbed terrain

Piecing together the events of the farthest touchdown a manmade spacecraft has ever made on an alien world reveals new clues about Titan’s surface and helps plan future missions to moons and planets.

The Huygens probe, ferried to Saturn’s moon Titan by NASA’s Cassini spacecraft, bounced, slid and wobbled its way to rest in the 10 seconds after touching down on Titan in January 2005, a new analysis reveals. The moon’s surface is more complex than previously thought.

Scientists reconstructed the chain of events by analyzing data from a variety of instruments that were active during the impact, in particular changes in the acceleration experienced by the probe. The probe was supplied by the European Space Agency and named after the Dutch 17th century astronomer Christiaan Huygens. (more…)

Researchers Devise More Accurate Method for Predicting Hurricane Activity

By Guest PostSeptember 14, 2012Environmentalok choudhary, cross validation, factor, forecasting, fredrick semazzi, historical data, humidity, hurricane season, method, model, motif based, nagiza samatova, network, north atlantic, north Carolina, seasonal hurricane, state university, statistical method, temperature, united states, william hendrix, zhengzhang chen

Researchers from North Carolina State University have developed a new method for forecasting seasonal hurricane activity that is 15 percent more accurate than previous techniques.

“This approach should give policymakers more reliable information than current state-of-the-art methods,” says Dr. Nagiza Samatova, an associate professor of computer science at NC State and co-author of a paper describing the work. “This will hopefully give them more confidence in planning for the hurricane season.” (more…)

Engineered Microvessels Provide a 3-D Test Bed for Human Diseases

By Guest PostMay 31, 2012Science3 d test bed, abraham stroock, abundant protein, bioengineering, blood clots, bloodstream, cancer, chemical factor, collagen, cornell university, disease, endothelial cells, honeycomb, human, human blood vessels, human cancer, human cell, jose lopez, mechanical, mice and monkeys, michael craven, model, petri dish, samuel totorica, shear stress, tumor progression, university of washington, ying zheng

Mice and monkeys don’t develop diseases in the same way that humans do. Nevertheless, after medical researchers have studied human cells in a Petri dish, they have little choice but to move on to study mice and primates.

University of Washington bioengineers have developed the first structure to grow small human blood vessels, creating a 3-D test bed that offers a better way to study disease, test drugs and perhaps someday grow human tissues for transplant.

The findings are published online this week in the Proceedings of the National Academy of Sciences. (more…)

Pollination with Precision: How Flowers Do It

By Guest PostMay 23, 2012Naturearabidopsis plants, brown university, chaotic frenzy, female gametes, fertilization, gamete fusion, hap2, kristin beale, logistical efficiency, mark johnson, mechanism, microscope, model, mothers day, mutant sperm, ovule, pollen grains, pollen tubes, pollination, polytubey, precision, reproduction, sex cells, sperm

Pollination could be a chaotic disaster. With hundreds of pollen grains growing long tubes to ovules to deliver their sperm to female gametes, how can a flower ensure that exactly two fertile sperm reach every ovule? In a new study, Brown University biologists report the discovery of how plants optimize the distribution of pollen for successful reproduction.

PROVIDENCE, R.I. [Brown University] — Next Mother’s Day, say it with an evolved model of logistical efficiency — a flower. A new discovery about how nature’s icons of romance manage the distribution of sperm among female gametes with industrial precision helps explain why the delicate beauties have reproduced prolifically enough to dominate the earth.

In pollination, hundreds of sperm-carrying pollen grains stick to the stigma suspended in the middle of a flower and quickly grow a tube down a long shaft called a style toward clusters of ovules, which hold two female sex cells. This could be a chaotic frenzy, but for the plant to succeed, exactly two fertile sperm should reach the two cells in each ovule — no more, no less. No ovule should be left out, either because too many tubes have gone elsewhere, or because the delivered sperm don’t work. (more…)

UCLA Researchers Map Damaged Connections in Phineas Gage’s Brain

By Guest PostMay 18, 2012Science1848 case, alzheimer's disease, andrei irimia, arthur w toga, behavioral change, brain, brain disorder, carinna m torgerson, cerebral cortex, computed tomographic data, emotional function, famous case, frontal temporal dementia, gage skull, history, human connectome project, jack van horn, laboratory, limbic structure, loni, mark wheeler, micah c chambers, microscopic links, model, myelin sheath, nerve fibers, neuro imaging, neurons, neuroscience, phineas gage, railroad, rod, san francisco, skull, south america, trajectory, traumatic brain injury, vermont, white matter

Famous 1848 case of man who survived a terrible accident has modern parallel

Poor Phineas Gage. In 1848, the supervisor for the Rutland and Burlington Railroad in Vermont was using a 13-pound, 3-foot-7-inch rod to pack blasting powder into a rock when he triggered an explosion that drove the rod through his left cheek and out of the top of his head. As reported at the time, the rod was later found, “smeared with blood and brains.”

Miraculously, Gage lived, becoming the most famous case in the history of neuroscience — not only because he survived a horrific accident that led to the destruction of much of his left frontal lobe but also because of the injury’s reported effects on his personality and behavior, which were said to be profound. Gage went from being an affable 25-year-old to one that was fitful, irreverent and profane. His friends and acquaintances said he was “no longer Gage.” (more…)

Microbe That Can Handle Ionic Liquids

By Guest PostMay 17, 2012Environment, Scienceanthropogenic chemicals, biofuel production, biofuels, blake simmons, carbon, cellulosic biomass, enterobacter lignolyticus, fossil fuels, hannah wooa, industry, ionic liquids, jane khudyakov, jbei, kristen deangelis, michael thelen, microbe, microorganisms, model, patrik dhaeseleer, properties, scf1 strain, semicrystalline, sharon borglin, soil bacterium, sugar fermenting microbes, switchgrass, Technology, toxic effect, tropical rainforest microbe

New Find From Joint BioEnergy Institute Could Help Reduce Biofuel Production Costs

In the search for technology by which economically competitive biofuels can be produced from cellulosic biomass, the combination of sugar-fermenting microbes and ionic liquid solvents looks to be a winner save for one major problem: the ionic liquids used to make cellulosic biomass more digestible for microbes can also be toxic to them. A solution to this conundrum, however, may be in the offing.

Researchers with the U.S. Department of Energy (DOE)’s Joint BioEnergy Institute (JBEI), a multi-institutional partnership led by Berkeley Lab, have identified a tropical rainforest microbe that can endure relatively high concentrations of an ionic liquid used to dissolve cellulosic biomass. The researchers have also determined how the microbe is able to do this, a discovery that holds broad implications beyond the production of advanced biofuels. (more…)