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Hips Take Walking in Stride; Ankles Put Best Foot Forward in Run

By Guest PostMay 30, 2011Scienceankles, applied force, captured data, dominic farris, energy, gregory sawicki, hips, human power lab, human walking, humans, knees, motors, next generation robotics, north carolina state university, physiology of wearable robotics, prosthetic devices, royal society scientific journal, running motions, sawicki and farris, treadmill, walk

In a first-of-its-kind study comparing human walking and running motions – and whether the hips, knees or ankles are the most important power sources for these motions – researchers at North Carolina State University show that the hips generate more of the power when people walk, but the ankles generate more of the power when humans run. Knees provide approximately one-fifth or less of walking or running power.

The research could help inform the best ways of building assistive or prosthetic devices for humans, or constructing next-generation robotics, say NC State biomedical engineers Drs. Dominic Farris and Gregory Sawicki. The co-authors of a study on the mechanics of walking and running in the journal Interface, a Royal Society scientific journal, Sawicki and Farris are part of NC State’s Human PoWeR (Physiology of Wearable Robotics) Lab. (more…)

Spitzer Sees Crystal ‘Rain’ in Outer Clouds of Infant Star

By Guest PostMay 30, 2011Scienceastronomers, bill danchi, charles poteet, clouds of gas, comets, constellation orion, crystals, deep impact missions, embryonic star, forsterite crystals, green mineral, herschel space observatory, hops 68, NASA, ohio, olivine, protostar, rain, solar system, spitzer space telescope, star, stardust, tom megeath, university of toledo, young stars

PASADENA, Calif. –– Tiny crystals of a green mineral called olivine are falling down like rain on a burgeoning star, according to observations from NASA’s Spitzer Space Telescope.

This is the first time such crystals have been observed in the dusty clouds of gas that collapse around forming stars. Astronomers are still debating how the crystals got there, but the most likely culprits are jets of gas blasting away from the embryonic star. (more…)

NASA’s WISE Mission Offers a Taste of Galaxies to Come

By Guest PostMay 28, 2011Scienceblue colors, california institute of technology, colorful galaxies, edward wright, flocculent galaxies, grand design spirals, ic 342, messier 51, messier 83, Milky Way, NASA, ngc 2403, ngc 5907, sky, spiral arms, tom jarrett, wide field infrared survey explorer mission, wise

PASADENA, Calif. — An assorted mix of colorful galaxies is being released today by NASA’s Wide-field Infrared Survey Explorer mission, or WISE. The nine galaxies are a taste of what’s to come. The mission plans to release similar images for the 1,000 largest galaxies that appear in our sky, and possibly more.

“Galaxies come in all sorts of delicious flavors,” said Tom Jarrett, a WISE team member at the Infrared Processing and Analysis Center, California Institute of Technology, in Pasadena, who studies our Milky Way’s neighboring galaxies. “Our first sample shows what WISE is capable of. We can produce spectacular high-resolution images of the largest galaxies.” (more…)

Scientists Discover Fossil of Giant Ancient Sea Predator

By Guest PostMay 27, 2011Scienceancient sea creatures, anomalocaridid creature, anomalocaridids, biodiversification, cambrian animals, cambrian explosion, cambrian period, complex ecosystems, deep-water, derek briggs, fossils, marine animals, marine fauna, marine predators, morocco, ordovician period, paleontologists, peter van roy, sea floor, sediment clouds

Paleontologists have discovered that a group of remarkable ancient sea creatures existed for much longer and grew to much larger sizes than previously thought, thanks to extraordinarily well-preserved fossils discovered in Morocco.

The creatures, known as anomalocaridids, were already thought to be the largest animals of the Cambrian period, known for the “Cambrian Explosion” that saw the sudden appearance of all the major animal groups and the establishment of complex ecosystems about 540 to 500 million years ago. Fossils from this period suggested these marine predators grew to be about two feet long. Until now, scientists also thought these strange invertebrates-which had long spiny head limbs presumably used to snag worms and other prey, and a circlet of plates around the mouth-died out at the end of the Cambrian. (more…)

Mars: Red Planet’s Rapid Formation Explains Its Small Size Relative to Earth

By Guest PostMay 27, 2011Scienceali pourmand, atmosphere, chemical behavior, chondrites, composition of chondrites, computer simulation, dauphas and pourmand, earth, embryos, enriqueta barrera, fine scale chronology, geophysicist, hafnium, lithophile elements, mantle of mars, mars, martian meteorites, national science foundation, nicolas dauphas, non volatile elements, nsf, radioactive decay, red planet, refractory, solar system, tungsten in meteorites, tungsten isotopic composition, university of chicago, xenon content

*Mars developed far more quickly than our blue planet*

Mars developed in as little as two to four million years after the birth of the solar system, far more quickly than Earth, according to results of a new study published in this week’s issue of the journal Nature.

The red planet’s rapid formation helps explain why it is so small, say the study’s co-authors, Nicolas Dauphas at the University of Chicago and Ali Pourmand at the University of Miami. (more…)

Just Four Percent of Galaxies Have Neighbors Like the Milky Way

By Guest PostMay 26, 2011Scienceanalyses of data, big bang, cdm, cold dark matter theory, computer model, formation of our galaxy, Galaxy, luminosity, magellanic clouds, Milky Way, nigel sharp, optical sky, risa wechsler, sdss, stanford university, universe

*Our home galaxy belongs to a rare subset among the billions that populate the cosmos*

How unique is the Milky Way?

To find out, a group of researchers led by Stanford University astrophysicist Risa Wechsler compared the Milky Way to similar galaxies and found that just four percent are like the galaxy Earth calls home. (more…)

Ants Give New Evidence for Interaction Networks

By Guest PostMay 25, 2011Culture, Scienceanna dornhaus, ant species, antennae, ants antennate, benjamin blonder, daniel wolf, dornhaus and blonder, evolutionary argument, Facebook, han jing, information, interaction networks, internet, kayla lauger, local grapevine, milan curry, paradigm, self directed networks, southern arizona, temnothorax rugatulus, trophallaxis, tuan cao, unique color code, university of arizona

*UA researchers have uncovered evidence in ant colonies suggesting that social networks may function differently than previously assumed.*

Be it through the Internet, Facebook, the local grapevine or the spread of disease, interaction networks influence nearly every part of our lives.

Scientists previously assumed that interaction networks without central control, known as self-directed networks, have universal properties that make them efficient at spreading information. Just think of the local grapevine: Let something slip, and it seems like no time at all before nearly everyone knows. (more…)

Replacing the Blue Bloods

By Guest PostMay 24, 2011Sciencebacterial endotoxin, bacterial infections, biological nature, endotoxin, endotoxin contamination, horseshoe crabs, lal, limulus amoebocyte lysate, liquid crystals, mary galvin, national science foundation, nick abbott, non lethal method, ordering, poisons, university of wisconsin

*Liquid crystal droplets could replace horseshoe crab blood in common endotoxin test*

The Food and Drug Administration requires every drug they certify to be tested for certain poisons that damage patient health. The current gold standard for this is the limulus amoebocyte lysate (LAL) assay that involves using the blood of horseshoe crabs, which strangely enough is blue, to test for endotoxin, a substance commonly associated with many symptoms caused by bacterial infections.

But researchers at the Department of Chemical and Biological Engineering at the University of Wisconsin-Madison have found what may be a more effective way to test for endotoxin that involves liquid crystals, the same material used to make some flat screen computer monitors and televisions. (more…)

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