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Asteroid 2011 AG5 – A Reality Check

By Guest PostMarch 2, 2012Sciencearizona, asteroid 2011 ag5, cassegrain reflector telescope, catalina mountains, don yeomans, earth interception, gravitational influence, mars, mount lemmon, near earth object, orbit, space rock, spaceguard, torino impact hazard scale, tucson

Asteroid 2011 AG5 has been receiving a lot of attention lately because of a very unlikely scenario which would place it on an Earth-interception course 28 years from now. Here is a scientific reality check of this relatively nondescript space rock which is currently ranked a “1” on the 1 to 10 Torino Impact Hazard Scale

As of Feb. 26, 2012, asteroid 2011 AG5 is one of 8,744 near-Earth objects that have been discovered. It is approximately 460 feet (140 meters) in size and its orbit carries it as far out as beyond Mars’ orbit and as close to the sun as halfway between Earth and Venus. It was discovered on Jan. 8, 2011, by astronomers using a 60-inch Cassegrain reflector telescope located at the summit of Mount Lemmon in the Catalina Mountains north of Tucson, Arizona. (more…)

How Megakaryocytes Get so Big — and The Bad Things That Happen When They Don’t

By Guest PostMarch 2, 2012Scienceblood cells, cell division, diane krause, DNA, ect2, ee chun cheng, elenoe smith, endomitosis, gef h1, gene, giant blood cells, guanine exchange factors, krause lab, leukemia, lin wang, malfunction, malignant leukemias, megakaryoblastic leukemias, megakaryocyte maturation, megakaryocytes, mkl1, mutant, platelets, process, protein, sharon lin, siying zou, stephanie halene, supernova, yuan gao

Yale researchers have discovered how megakaryocytes — giant blood cells that produce wound-healing platelets — manage to grow 10 to 15 times larger than other blood cells.

The findings, to be published March 13 in the journal Developmental Cell, also hint at how a malfunction in this process may cause a form of leukemia. (more…)

It Takes Two to Tango: Pairs of Entwined Proteins Handle The Stress

By Guest PostMarch 2, 2012Sciencebacterial protein, bleach, cell paper, dana reichmann, dance floor, function, helper protein, hsp33, jim erickson, michael fitzgerald, molecular chaperone, oxidants, protein, protein folding process, stress specific, tango, university of michigan, ursula jakob, ying xu

ANN ARBOR, Mich.— Imagine two tango dancers sweeping across the dance floor and suddenly encountering a slick spot. To avoid a slip or even a nasty tumble, the pair must work together to support one another and glide safely through the stressful moment.

In a similar way, a certain type of helper protein called a stress-specific molecular chaperone prevents its client proteins from collapsing during stressful situations by uncoiling a long, supportive arm that wraps around them, a University of Michigan-led research team has shown. (more…)

UCLA Scientists ID Cell, Signaling Pathway That Regulate Blood Stem Cells in Placenta

By Guest PostMarch 2, 2012Scienceblood stem cells, placenta, placental niche, placental vasculature, signaling pathway

UCLA stem-cell researchers have identified a certain type of cell and a signaling pathway in the placental niche that play a key role in stopping blood stem cells from differentiating into mature blood cells in the placenta. Preventing this premature differentiation is critical to ensuring a proper blood supply for an individual’s lifetime. (more…)

Torosaurus is Not Triceratops, Yale Researchers Say

By Guest PostMarch 1, 2012Scienceanatomical difference, dinosaur research, horned dinosaurs, torosaurus, triceratops

A year-long study by Yale University paleontologists concludes that two related horned dinosaurs are different animals and not adult and juvenile versions of the same. (more…)

Russian Dolls of the Bug World

By Guest PostMarch 1, 2012Scienceacyrthosiphon pisum, aphid alarm pheromone, aphidius ervi, aphids, apse, bacteriophage, bacterium, battle for survival, environmental sciences, Europe, hamiltonella defense, hemolymph, insect, kerry oliver, martha molly hunter, North America, parasite and host, parasitic wasps, pea aphid, russian dolls, symbiont, trans b farnesene, university of arizona, virus, wasp larva

Parasitic wasps using tiny insects known as aphids as living nurseries for their brood can sniff out whether the host insect is protected by symbiotic bacteria, researchers have discovered.

A research team including Martha (Molly) Hunter from the department of entomology in the University of Arizona’s College of Agriculture of Life Sciences has disentangled relationships in an assembly of players that resemble Russian dolls: a bacterium that lives inside a tiny insect, a virus that infects those bacteria, and a parasitic wasp that lays its eggs in the insect.

In a war between parasite and host, the parasitic wasp, Aphidius ervi, and the pea aphid, Acyrthosiphon pisum, are locked in a battle for survival. (more…)

When Continents Collide: A New Twist To a 50 Million-Year-Old Tale

By Guest PostMarch 1, 2012Scienceindia eurasia collision, indian plate movement, mountain building rate, plate boundaries, plate tectonics, tectonic plates

ANN ARBOR, Mich.— Fifty million years ago, India slammed into Eurasia, a collision that gave rise to the tallest landforms on the planet, the Himalaya Mountains and the Tibetan Plateau. (more…)

Solving a Spintronic Mystery:

By Guest PostFebruary 29, 2012Scienceberkeley lab, charge carriers, curie temperature, electron acceptors, electronic states, fermi level, ferromagnetic properties, gallium, gallium arsenide, gallium manganese arsenide, jacek furdyna, kin man yu, magneto optical data, margaret dobrowolska, mona berciu, rutherford backscattering facility, semiconductor, silicon, spin, spintronic devices, spintronic potential, spintronic technology, university of notre dame, valence energy band, wladek walukiewicz, xinyu liu

*Berkeley Lab Researchers Resolve Controversy Over Gallium Manganese Arsenide that Could Boost Spintronic Performance*

A long-standing controversy regarding the semiconductor gallium manganese arsenide, one of the most promising materials for spintronic technology, looks to have been resolved. Researchers with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) in collaboration with scientist from University of Notre Dame have determined the origin of the charge-carriers responsible for the ferromagnetic properties that make gallium manganese arsenide such a hot commodity for spintronic devices. Such devices utilize electron spin rather than charge to read and write data, resulting in smaller, faster and much cheaper data storage and processing. (more…)

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