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Prescription for double-dose algebra proves effective

By Guest PostMarch 26, 2013Sciencecps, double dose algebra, double period idea, education policy, elaine allensworth, everyday mathematics, failure rates, k 12 education, martin gartzman, math, melissa roderick, periods of algebra, Science, takako nomi, university of chicago

Martin Gartzman sat in his dentist’s waiting room last fall when he read a study in Education Next that nearly brought him to tears.

A decade ago, in his former position as chief math and science officer for Chicago Public Schools, Gartzman spearheaded an attempt to decrease ninth-grade algebra failure rates, an issue he calls “an incredibly vexing problem.” His idea was to provide extra time for struggling students by having them take two consecutive periods of algebra.

Gartzman had been under the impression that the double-dose algebra program he had instituted had only marginal results, but the study he read indicated otherwise. (more…)

Bio for nano

By Guest PostMarch 26, 2013Sciencebio inspired ideas, biomaterials, biomolecules, inorganic nanoparticles, nanomaterials, nanostructures in water, prototypes

Engineers work to create new biomaterials with energy technology applications

When automotive engineers want to create a new car, they don’t build thousands of prototypes. Instead, they create computer models and run simulations for performance, efficiency and desirability before a model is selected for fabrication. (more…)

Lunar impacts created seas of molten rock

By Guest PostMarch 25, 2013Scienceanalysis of data, apollo moon rocks, apollo program, brown university, crust, differentiation, differentiation processes, fluid rock, geological sciences, james w head, laser altimeter, liquid rock, lola, luna missions, lunar crust, lunar magma ocean, lunar orbiter, magma ocean paradigm, mantle, maunder crater, melt sea, model, molten rock, moon, NASA, orientale basin, orientale melt, planetary geologist, pristine rocks, remote sensing data, rock forming processes, rock layers, russia, william vaughan

A new analysis of data from NASA’s Lunar Orbiter Laser Altimeter (LOLA) shows that molten rock may have been present on the Moon more recently and for longer periods than previously thought. Differentiation — a settling out of rock layers as liquid rock cools — would require thousands of years and a fluid rock sea at least six miles deep.

PROVIDENCE, R.I. [Brown University] — Early in the Moon’s history an ocean of molten rock covered its entire surface. As that lunar magma ocean cooled over millions of years, it differentiated to form the Moon’s crust and mantle. But according to a new analysis by planetary scientists from Brown University, this wasn’t the last time the Moon’s surface was melted on a massive scale. (more…)

Before Dinosaurs’ Era, Volcanic Eruptions Triggered Mass Extinction

By Guest PostMarch 25, 2013Scienceend triassic extinction, magmatic activity, mass extinction, milankovich cycles, triassic extinction, volcanic eruptions

Increase in atmospheric carbon dioxide, global warming, ocean acidification killed 76 percent of species on Earth

More than 200 million years ago, a massive extinction decimated 76 percent of marine and terrestrial species, marking the end of the Triassic period and the onset of the Jurassic. (more…)

Surprising Control over Photoelectrons from a Topological Insulator

By Guest PostMarch 24, 2013Science3d topological insulators, alessandra lanzara, als, angle resolved, arpes, atoms, berkeley lab, chris jozwiak, data collection, dirac point, dung hai lee, electronic states, energy momentum diagrams, field of spintronics, flight analyzer, german, graphene, incident light, laser beam, magnetic surface, momentum space, p polarized, photoelectrons, photoemission spectroscopy, quantum computing, s polarization, s polarized, senkrecht, spin polarized, spin time, steve louie, strange crystalline materials, tis, topological insulator, university of california, zahid hussain

Berkeley Lab scientists discover how a photon beam can flip the spin polarization of electrons emitted from an exciting new material

Plain-looking but inherently strange crystalline materials called 3D topological insulators (TIs) are all the rage in materials science. Even at room temperature, a single chunk of TI is a good insulator in the bulk, yet behaves like a metal on its surface.

Researchers find TIs exciting partly because the electrons that flow swiftly across their surfaces are “spin polarized”: the electron’s spin is locked to its momentum, perpendicular to the direction of travel. These interesting electronic states promise many uses – some exotic, like observing never-before-seen fundamental particles, but many practical, including building more versatile and efficient high-tech gadgets, or, further into the future, platforms for quantum computing. (more…)

Sleep consolidates memories for competing tasks

By Guest PostMarch 24, 2013Nature, Scienceavian, brain, brain function, consolidate learning, daniel margoliash, development in birds, excellent model, formation, howard nusbaum, mammalian brains, sleep, stable memories, starlings, timothy brawn, university of chicago

Sleep plays an important role in the brain’s ability to consolidate learning when two new potentially competing tasks are learned in the same day, research at the University of Chicago demonstrates.

Other studies have shown that sleep consolidates learning for a new task. The new study, which measured starlings’ ability to recognize new songs, shows that learning a second task can undermine the performance of a previously learned task. But this study is the first to show that a good night’s sleep helps the brain retain both new memories. (more…)

Tooth pushes back modern monkeys’ first ancestor three million years

By Guest PostMarch 23, 2013Nature, Scienceancestor, andrew hill, anthropologists, baboons, basal african monkeys, central kenya, cercopithecid family, christopher c gilbert, city, clayton stephenson, family victoriapithecidae, great rift valley, hunter college, james b rossie, lineage, macaques, million years ago, modern african monkeys, monkey family tree, new york, old world monkey, sallye stephenson, schwartz family foundation, stony brook university, teeth, tugen hills, vervet monkeys, yale university

The ancestor of all modern African monkeys was alive 3 million years earlier than previously thought and coexisted with members of a now-extinct branch of the monkey family tree, according to new evidence from anthropologists.

“We pushed back the origin of modern monkeys by a huge chunk of time,” said anthropologist Andrew Hill of Yale University, the senior researcher on the project. “This means there are all sorts of things we can think about. You can start to look at animal interactions that might have taken place.” (more…)

Researchers Solve Riddle of What Has Been Holding Two Unlikely Materials Together

By Guest PostMarch 23, 2013Sciencebi2te3, bismuth telluride, bonds, electricity, electronics, gaas, gallium arsenide, heat into electricity, houston dycus, james lebeau, jonathan pierce, molecules, north Carolina, rama venkatasubramanian, rti international, state university, super x, thin films, van der waals, weak electrical forces

For years, researchers have developed thin films of bismuth telluride (Bi2Te3) – which converts heat into electricity or electricity to cooling – on top of gallium arsenide (GaAs) to create cooling devices for electronics. But while they knew it could be done, it was not clear how – because the atomic structures of those unlikely pair of materials do not appear to be compatible. Now researchers from North Carolina State University and RTI International have solved the mystery, opening the door to new research in the field.

“We’ve used state-of-the-art technology to solve a mystery that has been around for years,” says Dr. James LeBeau, an assistant professor of materials science and engineering at NC State and co-author of a paper on the research. “And now that we know what is going on, we can pursue research to fine-tune the interface of these materials to develop more efficient mechanisms for converting electricity to cooling or heat into electricity. Ultimately, this could have applications in a wide range of electronic devices.” (more…)

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