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Powerful Mathematical Model Greatly Improves Predictions for Species Facing Climate Change

By Guest PostDecember 4, 2011Environment, Nature, Scienceatmosphere and oceans, beetle, bridgett vonholdt, carbon dioxide emissions, coat color gene, coat color phenotype, daniel macnulty, daniel stahler, earth temperature, ecological impacts, ecological model, ecological parameters, ecosystem, Environment, environmental change, general model, genetics, global warming, gray wolf, grizzly bears, harmony, health of populations, heterozygotes, high arctic, integral projection model, ipm, mathematical model, new model, plants, polar bear, population ecology, population genetics, predictive model, quantitative genetics, robert wayne, species, sub fields of ecology, tim coulson, trophic cascade, wolf, wolf population, wolves, yellowstone, yellowstone national park

UCLA life scientists and colleagues have produced the most comprehensive mathematical model ever devised to track the health of populations exposed to environmental change.

The research, federally funded by the National Science Foundation, is published Dec. 2 in the journal Science.

The team’s groundbreaking integral projection model, or IPM, unites various sub-disciplines of population biology, including population ecology, quantitative genetics, population genetics, and life-span and offspring information, allowing researchers to link many different data sources simultaneously. Scientists can now change just a single variable, like temperature, and see how that affects many factors for a population. (more…)

Moral Dilemma: Would You Kill One Person to Save Five?

By Guest PostDecember 3, 2011Science3 d simulated, carlos david navarrete, evolutionary psychologist, greater good, michigan state university, moral dilemma, runaway boxcar, sensors, three dimensional setting, trolley problem, violate

EAST LANSING, Mich. — Imagine a runaway boxcar heading toward five people who can’t escape its path. Now imagine you had the power to reroute the boxcar onto different tracks with only one person along that route.

Would you do it?

That’s the moral dilemma posed by a team of Michigan State University researchers in a first-of-its-kind study published in the research journal Emotion. Research participants were put in a three dimensional setting and given the power to kill one person (in this case, a realistic digital character) to save five. (more…)

Frogs’ Amazing Leaps Due to Springy Tendons

By Guest PostDecember 3, 2011Nature, Science3 d x ray video technology, biomechanics of frog jumping, brown university, bush babies, calaveras county, elastic mechanism, elastic structure, frog jumping, frog jumping competition, frogs, grasshopper, guinea fowl, henry astley, humble flea, invertebrates, milliseconds, muscles, northeast united states, northern leopard frog, pond frog, rana pipiens, richard lewis, species of frogs, thomas roberts, vertebrates

*The secret to frogs’ superlative jumping lies in their tendons. Researchers at Brown University, filming frogs jumping at 500 frames per second with special X-ray technology, show that the frog’s tendon stretches as it readies its leap and then recoils, much like a spring, when the frog jumps. The finding could explain how other animals are exceptional leapers. Results appear in Biology Letters.*

PROVIDENCE, R.I. [Brown University] — Some species of frogs and many other animals are able to jump far beyond what appear to be their capabilities. The trained contestants in the frog-jumping competition in Calaveras County, Calif., come to mind, but even ordinary frogs can leap several times farther than their physiology would seem to allow.

“Muscles alone couldn’t produce jumps that good,” said Henry Astley, who studies the biomechanics of frog jumping at Brown University. (more…)

Watching the Nervous System Being Wired in Real Time

By Guest PostDecember 2, 2011Sciencebill hathaway, daniel colon ramos, imaging technology, living organism, migration of cells, nervous system, neurodevelopmental atlas, new diseases, single cell, worm, yale, yale cell biologist, yale university

Thanks to a new imaging technology developed at Yale, the National Institutes of Health and Sloan-Kettering, scientists can now see for the first time the development of a living organism at the level of a single cell.

One of the developers, Yale cell biologist Daniel Colon-Ramos, illustrates the power of the new technology in this video that shows the migration of cells that will form the nervous system in a developing worm. (more…)

UCLA Scientists Engineer Blood Stem Cells to Fight Melanoma

By Guest PostDecember 1, 2011Health, Scienceantigen, blood stem cells, cancer and stem cell, cancer patient, caucasians, dimitrios n vatakis, DNA, genes, genetically engineered, human melanoma, immune system, jerome zack, microbiology, mouse models, PET, positron emission tomography, t cell receptor, t cells, viral vehicle

Researchers from UCLA’s cancer and stem cell centers have demonstrated for the first time that blood stem cells can be engineered to create cancer-killing T-cells that seek out and attack a human melanoma. The researchers believe the approach could be useful in about 40 percent of Caucasians with this malignancy.

Done in mouse models, the study serves as the first proof-of-principle that blood stem cells, which make every type of cell found in the blood, can be genetically altered in a living organism to create an army of melanoma-fighting T-cells, said Jerome Zack, the study’s senior author and a scientist with UCLA’s Jonsson Comprehensive Cancer Center and the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA. (more…)

Physicists Set Strongest Limit on Mass of Dark Matter

By Guest PostNovember 30, 2011Sciencedark energy, dark matter, dark matter collisions, dark matter particle, detecting dark matter, expansion of universe, mass

Brown University physicists have set the strongest limit for the mass of dark matter, the mysterious particles believed to make up nearly a quarter of the universe. The researchers report in Physical Review Letters that dark matter must have a mass greater than 40 giga-electron volts. The distinction is important because it casts doubt on recent results from underground experiments that have reported detecting dark matter

PROVIDENCE, R.I. [Brown University] — If dark matter exists in the universe, scientists now have set the strongest limit to date on its mass. (more…)

A Smarter Way to Make Ultraviolet Light Beams

By Guest PostNovember 30, 2011Scienceharmonic distortions, information storage, infrared signal, jeremy moore, lasers, matthew tomes, microscopy, mona jarrahi, optical resonator, optics express, original wavelength, tal carmon, ultraviolet light, university of michigan, wavelength tunable ultraviolet sources

ANN ARBOR, Mich.— Existing coherent ultraviolet light sources are power hungry, bulky and expensive. University of Michigan researchers have found a better way to build compact ultraviolet sources with low power consumption that could improve information storage, microscopy and chemical analysis.

A paper on the research is newly published in Optics Express. The research was led by Mona Jarrahi and Tal Carmon, assistant professors in the Department of Electrical Engineering and Computer Science. The experiment was performed by Jeremy Moore and Matthew Tomes, both graduate students in the same department. (more…)

Fast Times in Physics

By Guest PostNovember 29, 2011Scienceatomic clocks, beams of neutrinos, c, Chicago, einstein, equation, Europe, faster than light, fermilab, Japan, marvin marshak, minos, neutrinos, northern minnesota, opera, physicists, scientific world, soudan underground laboratory, speed of light, subatomic particles, time, university of minnesota, vacuum, vibrations of cesium atoms

A U physicist will help determine if neutrinos can outrace light

Back in 2007, a physics experiment clocked elusive subatomic particles called neutrinos going faster than light.

That wasn’t supposed to happen. If the speed of light in a vacuum—denoted “c” by physicists—isn’t the universal speed limit, it would mean that Einstein put the wrong number in his famous E=mc² equation.

University of Minnesota physicist Marvin Marshak was part of the experiment, called MINOS. It clocked beams of neutrinos shot from Fermilab, a national physics lab near Chicago, to a detector 457 miles away in the Soudan Underground Laboratory in northern Minnesota. (more…)

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