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Breakthrough in Nanocrystals Growth

By Guest PostOctober 19, 2010Scienceadvanced photon source, aps, argonne national laboratory, biological sensors, carnegie, center for nanoscale, chemical, diffraction, high pressure synergetic consortium, hpsync, hpsync program, metal-conducting liquid, nanoletters, nanoparticles, nanoparticles grow, Nanotechnology, russell hemley, solar-cell technology, wenge yang, x-rays

Nanoparticles. Image credit: Wenge Yang

Argonne, ILL — For the first time scientists have been able to watch nanoparticles grow from the earliest stages of their formation. Nanoparticles are the foundation of nanotechnology and their performance depends on their structure, composition, and size. Researchers will now be able to develop ways to control conditions under which they are grown. The breakthrough will affect a wide range of applications including solar-cell technology and chemical and biological sensors. The research is published in NANOLetters.

As coauthor Wenge Yang of the Carnegie Institution’s Geophysical Laboratory explained: “It’s been very difficult to watch these tiny particles be born and grow in the past because traditional techniques require that the sample be in a vacuum and many nanoparticles are grown in a metal-conducting liquid. So we have not been able to see how different conditions affect the particles, much less understand how we can tweak the conditions to get a desired effect.” (more…)

Haiti Earthquake Shaking Amplified by Local Landforms

By Guest PostOctober 19, 2010Scienceaftershock recordings, earthquake in haiti, geological conditions, haiti earthquake

PORT-AU-PRINCE, Haiti — The severe damage and loss-of-life caused by the devastating January 2010 M7.0 earthquake in Haiti was exacerbated by amplification of shaking due to local geological conditions and landforms in Port-au-Prince, according to a study published online today in Nature Geoscience. (more…)

U of T Biologists Identify Influence of Environment on Sexual vs. Asexual Reproduction

By Guest PostOctober 18, 2010Scienceasexual reproduction, evolutionary biologist, homogenous environment, sexual reproduction, tree of life

Evolutionary biologists at U of T have found that environment plays a key role in determining whether a species opts for sexual over asexual reproduction. (more…)

A River Ran Through It

By Guest PostOctober 17, 2010Nature, Sciencealan tessier, arizona state university, climate change, colorado, colorado river delta, downstream, ecosystems, food chain, grand canyon, humans, irrigation, jacques finlay, john sabo, las vegas, los angeles, minneapolis, Mississippi, new york city, Phoenix, river flows, rivers, sea of cortez, small tributaries, storm floods, streams

About the image: A now dry Colorado River delta branches into the Baja/Sonoran Desert near the Sea of Cortez. Image credit: Pete McBride

Rivers and streams supply the lifeblood to ecosystems across the globe, providing water for drinking and irrigation for humans as well as a wide array of life forms from single-celled organisms up to the fish humans eat.

But humans and nature itself are making it tough on rivers to continue in their central role to support fish species, according to new research by a team of scientists including John Sabo, a biologist at Arizona State University.

Globally, rivers and streams are being drained due to human use and climate change. These and other human impacts alter the natural variability of river flows.

Some affected rivers have dried and no longer run, while others have seen increases in the variability of flows due to storm floods. (more…)

Giant Star Goes Supernova — and is Smothered by Its Own Dust

By Guest PostOctober 16, 20105 commentsScience10-meter keck telescope, active galactic nuclei, agn, astronomers, christopher kochanek, deep wide field survey, eta carinae, Galaxy, giant star, hawaii, homunculus nebula, hypernova, krzysztof stanek, light years, Milky Way, milky way galaxy, NASA, ohio state university, spitzer space telescope, star system, super-massive black holes, supernovae, szymon kozlowski, wide field infrared explorer, wise

COLUMBUS, Ohio — A giant star in a faraway galaxy recently ended its life with a dust-shrouded whimper instead of the more typical bang.

Ohio State University researchers suspect that this odd event — the first one of its kind ever viewed by astronomers – was more common early in the universe. (more…)

Using Discards, Scientists Discover Different Dinosaurs’ Stomping Grounds

By Guest PostOctober 16, 2010Scienceceratopsians, dinosaur, duck-billed dinosaurs, fossils, hadrosaurs, herbivores, late cretaceous, montana, nicholas longrich, North America, ornithopod, period, thescelosaurus, triceratops, tyler lyson, tyrannosaurs rex, western canada, yale university, yyoming

By examining the type of rock in which dinosaur fossils were embedded, an often unappreciated part of the remains,

Certain dinosaur species liked to live in different habitats, separated by only a few miles. Image credit: Nicholas Longrich

scientists have determined that different species of North American dinosaurs from the Late Cretaceous period 65 million years ago occupied different environments separated by just a few miles.

Hadrosaurs or duck-billed dinosaurs, along with the small ornithopod Thescelosaurus, preferred to live along the edge of rivers, according to the research. Ceratopsians, on the other hand, which include the well-known Triceratops, preferred to be several miles inland.

The findings, which appear in the online edition of the Proceedings of the Royal Society B, give scientists a more complete picture of the distribution of different species and help explain how several large herbivores managed to coexist. (more…)

For Those Who Don’t Exercise or Watch Their Diets, CU ‘Nutraceutical’ Research Could Help

By Guest PostOctober 16, 2010Health, Scienceaging process, anti-inflammatory, ashley walker, bad cholesterol, behavioral changes, brad fleenor, cardiovascular disease, curcumin, douglas r seals, exercise, good nutrition, integrative physiology of aging laboratory, kevin strickfaden, ldl, molly russell, noah larsen, nutraceuticals, salt restriction, united states' no 1 killer, university of colorado at boulder, vitamin D, vitamin supplements, weight loss

University of Colorado at Boulder Professor Douglas R. Seals has amassed scientific evidence indicating that exercise, weight loss, good nutrition and salt restriction can cut your chances of getting cardiovascular disease, the United States’ No. 1 killer.

But Seals knows that exhorting people to exercise and lose weight, no matter how well the case is buttressed with data, will only go so far. So Seals’ laboratory has begun researching “nutraceuticals,” food extracts or vitamin supplements that could mimic the effects of a healthful lifestyle. (more…)

Taking Measure of the Greenhouse Effect

By Guest PostOctober 15, 20101 commentEnvironment, Scienceaerosols, andrew lacis, atmosphere, carbon dioxide, climate change, climate models, climate science, clouds, CO2, CO2 emissions, computer simulations, earth, gases, gavin schmidt, goddard institute for space studies, greenhouse effect, greenhouse gases, heat-absorbing components, heat-trapping gas, methane, mining activities, NASA, nitrous oxide, ozone, planet, reto ruedy, ron miller, trace gases, water vapor

WASHINGTON — Scientists have long known that heat-absorbing components of Earth’s atmosphere, such as clouds and certain gases, prevent our planet from being an ice-covered ball. Now a study, for the first time, comprehensively calculates the relative contributions of the components responsible for that heating, known as the greenhouse effect.

Besides clarifying an important aspect of climate science, the study also demonstrates that rising concentrations of one heat-trapping gas — carbon dioxide — leads to much more greenhouse warming than just the heat the gas absorbs directly itself.

Various studies have looked at the contributions of water vapor, CO₂, and other greenhouse gases. But none had systematically estimated the contributions of each of the main players, says climate scientist Gavin Schmidt of NASA Goddard Institute for Space Studies, and lead author of the new research. (more…)

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