Author Archives: Guest Post

Foundations of Carbon-Based Life Leave Little Room for Error

By Guest PostApril 2, 2013Sciencealpha particles, carbon, carbon 12, carbon based life, dean lee, deutsche forschungsgemeinschaft, electron volts, elementary particles, elements, evgeny epelbaum, helium 4 nuclei, hermann krebs, hoyle state, juelich supercomputer centre, kev, light quark mass, north Carolina, numerical lattice, oxygen, quarks, room for error, specific energy, state university, timo laehde, ulf g

Life as we know it is based upon the elements of carbon and oxygen. Now a team of physicists, including one from North Carolina State University, is looking at the conditions necessary to the formation of those two elements in the universe. They’ve found that when it comes to supporting life, the universe leaves very little margin for error.

Both carbon and oxygen are produced when helium burns inside of giant red stars. Carbon-12, an essential element we’re all made of, can only form when three alpha particles, or helium-4 nuclei, combine in a very specific way. The key to formation is an excited state of carbon-12 known as the Hoyle state, and it has a very specific energy – measured at 379 keV (or 379,000 electron volts) above the energy of three alpha particles. Oxygen is produced by the combination of another alpha particle and carbon. (more…)

CU study provides new evidence ancient asteroid caused global firestorm on Earth

By Guest PostApril 2, 2013Scienceboulder, charcoal, chicxulub crater, cretaceous paleogene, dinosaur days, douglas robertson, earth, earth atmosphere, geological evidence, global firestorm, infrared heat pulse, k pg boundary, manhattan sized asteroid, mass extinctions, Mexico, milwaukee public museum, peter sheehan, radiation, region, sedimentation rates, university of colorado, william lewis, wisconsin, yucatan peninsula

A new look at conditions after a Manhattan-sized asteroid slammed into a region of Mexico in the dinosaur days indicates the event could have triggered a global firestorm that would have burned every twig, bush and tree on Earth and led to the extinction of 80 percent of all Earth’s species, says a new University of Colorado Boulder study.

Led by Douglas Robertson of the Cooperative Institute for Research in Environmental Sciences, or CIRES, the team used models that show the collision would have vaporized huge amounts of rock that were then blown high above Earth’s atmosphere. The re-entering ejected material would have heated the upper atmosphere enough to glow red for several hours at roughly 2,700 degrees Fahrenheit — about the temperature of an oven broiler element — killing every living thing not sheltered underground or underwater. (more…)

New Study Reveals How Sensitive U.S. East Coast Regions May Be to Ocean Acidification

By Guest PostApril 1, 2013Environmentacidic, acidic environment, bicarbonate, buffer capacity, carbon dioxide, carbon in ocean, carbonate, carbonic acid, changes in acidity, chemical survey, CO2, co2 levels, coastal ocean acidification, continental scale, coral, corpus christi, dic, dissolved co2, dissolved inorganic carbon, florida strait, galveston, georgia, glaciers, gulf of maine, gulf of mexico, influx of co2, labrador sea, melting sea ice, middle atlantic bight, Mississippi, ocean acidification, offshore, oysters, pteropods, rik wanninkhof, robert h byrne, ronald h brown, snails, texas, total alkalinity, tsung hung peng, university of georgia, us east coast, water ph, whoi, wie jen huang, wie jun cai, xinping hu, zhaohui aleck wang

A continental-scale chemical survey in the waters of the eastern U.S. and Gulf of Mexico is helping researchers determine how distinct bodies of water will resist changes in acidity. The study, which measures varying levels of carbon dioxide (CO₂) and other forms of carbon in the ocean, was conducted by scientists from 11 institutions across the U.S. and was published in the journal Limnology and Oceanography.

“Before now, we haven’t had a very clear picture of acidification status on the east coast of the U.S.,” says Zhaohui ‘Aleck’ Wang, the study’s lead author and a chemical oceanographer at Woods Hole Oceanographic Institution (WHOI). “It’s important that we start to understand it, because increase in ocean acidity could deeply affect marine life along the coast and has important implications for people who rely on aquaculture and fisheries both commercially and recreationally.” (more…)

Berkeley Lab Researchers Use Metamaterials to Observe Giant Photonic Spin Hall Effect

By Guest PostApril 1, 2013Scienceantenna configurations, arm configuations, artificial nanoconstructs, berkeley lab, ccd, charge coupled device, doe, electron, future of computing, geometry parameters, gold nanoantennas, hall effect, image, junsuk rho, magnetic moment, metamaterials, optical properties, photonic spin, physical motion, physicist edwin hall, quantized angular momentum, quantum measurements, quantum mechanics, scanning electron microscopy, spin, xiang zhang, xiaobo yin, yuan wang, ziliang ye

Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have once again demonstrated the incredible capabilities of metamaterials – artificial nanoconstructs whose optical properties arise from their physical structure rather than their chemical composition. Engineering a unique two-dimensional sheet of gold nanoantennas, the researchers were able to obtain the strongest signal yet of the photonic spin Hall effect, an optical phenomenon of quantum mechanics that could play a prominent role in the future of computing.

“With metamaterial, we were able to greatly enhance a naturally weak effect to the point where it was directly observable with simple detection techniques,” said Xiang Zhang, a faculty scientist with Berkeley Lab’s Materials Sciences Division who led this research. “We also demonstrated that metamaterials not only allow us to control the propagation of light but also allows control of circular polarization. This could have profound consequences for information encoding and processing.” (more…)

Misregulated genes may have big autism role

By Guest PostApril 1, 2013Healthautism, autism cerebral cortex, bank, biochemical exchanges, brain tissue, brains of children, brown university, christianson syndrome, daniel geschwind, endosomes of cells, epilepsy, eric morrow, genetic pathway, human behavior, irinia voineagu, karoly mirnics, key molecular player, krassimira garbett, los angeles, messenger rna, misregulated genes, mutations, nhe6, nhe9, proteins, raw data, statistical analysis, university of california, vanderbilt university

A genetic pathway involving proteins in the endosomes of cells appears to be misregulated in the brains of children with autism, according to a newly published statistical analysis in the journal Molecular Psychiatry. Previously the genes were shown to cause rare forms of the disease but the new study suggests they have a wider role.

PROVIDENCE, R.I. [Brown University] — A new study finds that two genes individually associated with rare autism-related disorders are also jointly linked to more general forms of autism. The finding suggests a new genetic pathway to investigate in general autism research. (more…)

Multi-Toxin Biotech Crops Not Silver Bullets, UA Scientists Warn

By Guest PostMarch 31, 2013Environment, Natureafrica, bacillus thuringiensis, bacterium, biotech crops, bruce tabashnik, bt, bt cotton, bt toxin, caterpillars, cirad, corn earworm, cotton bollworm, cry1, cry1ac, cry2 toxins, cry2ab, entomologists, Environment, epa, genetically engineered crops, helicoverpa zea, insecticide sprays, multi toxin, one toxin, pest control, pest killing proteins, pyramid strategy, silver bullets, simulation models, two toxin, university of arizona, US, yves carriere

The popular new strategy of planting genetically engineered crops that make two or more toxins to fend off insect pests rests on assumptions that don’t always apply, UA researchers have discovered. Their study helps explain why one major pest is evolving resistance much faster than predicted and offers ideas for more sustainable pest control.

A strategy widely used to prevent pests from quickly adapting to crop-protecting toxins may fail in some cases unless better preventive actions are taken, suggests new research by University of Arizona entomologists published in the Proceedings of the National Academy of Sciences.

Corn and cotton have been genetically modified to produce pest-killing proteins from the bacterium Bacillus thuringiensis, or Bt for short. Compared with typical insecticide sprays, the Bt toxins produced by genetically engineered crops are much safer for people and the environment, explained Yves Carrière, a professor of entomology in the UA College of Agriculture and Life Sciences who led the study. (more…)

‘Sideline quasars’ helped to stifle early galaxy formation, says CU study

By Guest PostMarch 31, 2013Scienceastronomers, big bang, black holes, boulder, brightest quasars, caltech astronomer, cos, cosmic web, dark ages, david syphers, early universe, Epoch, fossil record, galaxy formation, gaseous material, gases in universe, generations of stars, helium atoms, helium gas, helium reionization era, Hubble Space Telescope, intergalactic global warming, intergalactic medium, ionizing radiation, lighthouse, maarten schmidt, michael shull, neutral helium gas, planetary sciences, plasma, quasar, quasi stellar, radio source, sideline quasars, stars or galaxies, swiss cheese, ultraviolet spectrograph, universe, university of colorado

University of Colorado Boulder astronomers targeting one of the brightest quasars glowing in the universe some 11 billion years ago say “sideline quasars” likely teamed up with it to heat abundant helium gas billions of years ago, preventing small galaxy formation.

CU-Boulder Professor Michael Shull and Research Associate David Syphers used the Hubble Space Telescope to look at the quasar — the brilliant core of an active galaxy that acted as a “lighthouse” for the observations — to better understand the conditions of the early universe. The scientists studied gaseous material between the telescope and the quasar with a $70 million ultraviolet spectrograph on Hubble designed by a team from CU-Boulder’s Center for Astrophysics and Space Astronomy. (more…)

Endangered Lemurs’ Genomes Sequenced

By Guest PostMarch 31, 2013Natureaakrosh ratan, african agriculturalists, anthropologist, aquarium, aye aye populations, aye ayes, biologist, dna samples, ecological niche, edward louis, endangered lemur, european descent, forest habitats, fragmentation, Galaxy, genetically distinct, genome, george perry, henry doorly zoo, human dna sequence, human genetic diversity, loss, Madagascar, madagascar biodiversity, national science foundation, omaha, open source, oscar bedoya reina, penn state university, population, regions of madagascar, richard burhans, sequence, simon malcomber, software, southeast asian, stephan schuster, type of lemur, webb miller, woodpecker

Three populations of aye-ayes on Madagascar studied

For the first time, the complete genomes of three populations of aye-ayes–a type of lemur–have been sequenced and analyzed.

The results of the genome-sequence analyses are published this week in the journal Proceedings of the National Academy of Sciences (PNAS). (more…)