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Enormous scale of Nile ‘mega lake’ revealed

By Guest PostJanuary 19, 2014Environment, Sciencedavid haberlah, east africa, eastern sahara desert, egypt, exposure, isotope beryllium 10, lake baikal, lake michigan, lake tanganyika, nile mega lake, shoreline deposits, Siberia, sudan, surface area, tim barrows, university of exeter, US, valley, white nile river

The eastern Sahara Desert was once home to a 45,000 km²freshwater lake similar in surface area to the largest in the world today.

A study led by the University of Exeter has revealed that the mega lake was probably formed more than one hundred thousand years ago in the White Nile River Valley in Sudan.

Dr Tim Barrows of the University of Exeter and colleagues used a dating approach based on exposure to cosmic rays to measure the amount of the isotope beryllium-10 in shoreline deposits. Its abundance can be used to calculate how long rocks or sediments have been exposed at the surface of the earth. (more…)

Studies in perception: At arm’s length: Plasticity of depth judgment

By Guest PostJanuary 19, 2014Science3d, brown university, carlo fantoni, computer generated image, corrado caudek, depth judgment, depth perception, fulvio domini, iit, italy, john assad, journal of neuroscience, plasticity, robert volcic, smartphone, studies in perception, three rods, training exercise, triangle configuration, virtual 3d cylinder

People have a distance at which they are best able to judge depth. That distance, it turns out, is dictated by how long people understand their arms to be. Researchers showed this in the Journal of Neuroscience by tricking subjects with virtual reality into thinking their reach was longer than it really was. The result? Their accurate perception of depth via sight moved outward and touch became more sensitive.

PROVIDENCE, R.I. [Brown University] — We need to reach for things, so a connection between arm length and our ability to judge depth accurately may make sense. Given that we grow throughout childhood, it may also seem reasonable that such an optimal depth perception distance should be flexible enough to change with a lengthening arm. Recent research in the Journal of Neuroscience provides evidence for these ideas with surprising findings: Scientists showed that they could manipulate the distance at which adult volunteers accurately perceived depth, both through sight and touch, by tricking them into thinking they had a longer reach than they really do. (more…)

Study: CT Scans Could Bolster Forensic Database to ID Unidentified Remains

By Guest PostJanuary 19, 2014Sciencecraniofacial surgeons, ct scans, forensic database, reconstructive surgery, unidentified remains

A study from North Carolina State University finds that data from CT scans can be incorporated into a growing forensic database to help determine the ancestry and sex of unidentified remains. The finding may also have clinical applications for craniofacial surgeons. (more…)

Smart hydrogels

By Guest PostJanuary 18, 2014Scienceacs, americans, anti inflammatory activity, arthritis foundation, biomacromolecules, chandran sabanayagam, Chicago, darrin pochan, DNA, drug molecules, gel is biocompatible, high tension, hip joint, hyaluronic acid, knee, ligament tears, longxi xiao, mechanical force, osteoarthritis, ph, researchers, rush university, smart hydrogels, stimulate tissue regeneration, temperature, treatment efficacy, university of delaware, xinqiao jia, yingchao chen, zhixiang tong

UD-developed smart gels deliver medicine on demand

Researchers at the University of Delaware have developed a “smart” hydrogel that can deliver medicine on demand, in response to mechanical force.

Over the past few decades, smart hydrogels have been created that respond to pH, temperature, DNA, light and other stimuli. (more…)

Cilia use different motors for different tasks

By Guest PostJanuary 17, 2014Scienceanita zimmerman, brown biologist, brown university, cilia, hair like fibers, ilyong jung, james valles, liquid, locomotion, motor behaviors, oral groove, plain water, single celled paramecia, tiny oars, viscosity, viscosity of water

Cilia — short, hair-like fibers — are widely present in nature. Single-celled paramecia use one set of cilia for locomotion and another set to sweep nutrients into their oral grooves. Researchers at Brown have discovered that those two cilia sets operate at different speeds when the viscosity of the environment changes. That suggests different molecular motors driving them, which could help explain how cilia have come to be used for so many different tasks in nature.

PROVIDENCE, R.I. [Brown University] — Cilia are one of nature’s great multipurpose tools. The tiny, hair-like fibers protrude from cell membranes and perform all kinds of tasks in all kinds of creatures, from helping clear debris from human lungs to enabling single-celled organisms to swim. Now, physicists from Brown University have discovered something that could help scientists understand how cilia have been adapted for so many varied tasks. (more…)

‘Standing on a comet’: Rosetta mission will contribute to space weather research

By Guest PostJanuary 16, 2014Scienceandre bieler, archeological artifacts, carbon dioxide, churyumov gerasimenko, comet 67p, comet bound spacecraft, electric grid, electrified particles, european space agency, evolution, ionosphere, kenneth hansen, michael combi, model, on a comet, orbit of neptune, origin, planets, rosetta, rosetta mission, rosetta mission lander, rosetta orbiter, satellites, solar system, space weather research, standing, sun, tamas gombosi, the philae lander, university of michigan, valeriy tenishev

ANN ARBOR — A comet-bound spacecraft that’s been in sleep mode for more than two years is scheduled to wake up on the morning of Jan. 20—beginning the home stretch of its decade-long journey to a mile-wide ball of rock, dust and ice.

If all goes as planned, Rosetta—a European Space Agency-led mission that involves University of Michigan engineers and scientists—will be the first craft to actually land on a comet as well as track it for an extended period of time. (more…)

Discovery spotlights key role of mystery RNA modification in cells

By Guest PostJanuary 16, 2014Sciencecell differentiation, cells, chuan he, demethylation, deoxyribonucleic acid, diabetes, discovery, DNA, exact function, healthy cells, infertility, key role, m6a, messenger ribonucleic acid, methyl, methylation, mrna, mrna in question, mystery, n6 methyladenosine, neurobiology, obesity, organic compounds, parameter, peking university, proteins, regulating mrna lifetime, rna modification, san diego, sequence, university of california, university of chicago, xiao wang, ythdf2

Researchers had known for several decades that a certain chemical modification exists on messenger ribonucleic acid (mRNA), which is essential to the flow of genetic information. But only recently did experiments at the University of Chicago show that one major function of this modification governs the longevity and decay of RNA, a process critical to the development of healthy cells.

The chemical modification on mRNA in question is called N⁶-methyladenosine (m⁶A). A recent study by UChicago scientists reveals how the m⁶A modification on mRNA could affect the half-life of mRNA that in turn regulates cellular protein quantities. That discovery could provide fundamental insights into healthy functioning and disorders such as obesity, diabetes and infertility. (more…)

Tiny acts of microbe justice help reveal how nature fights freeloaders

By Guest PostJanuary 16, 2014Sciencebacteria vibrio cholerae, bioremediation, biosphere, bonnie bassler, carey nadell, fights freeloaders, history, howard stone, industrial cleanup, infection, knut drescher, life on earth, mechanism, microbe, nitrogen containing molecules, princeton university, public goods dilemma, recycle, tiny acts, treating a disease, v cholera

The idea of everyone in a community pitching in is so universal that even bacteria have a system to prevent the layabouts of their kind from enjoying the fruit of others’ hard work, Princeton University researchers have discovered.

Groups of the bacteria Vibrio cholerae deny loafers their unjust desserts by keeping the food generated by the community’s productive members away from V. cholerae that attempt to live on others’ leftover nutrients, the researchers report in the journal Current Biology. The researchers found that individual bacteria produce a thick coating around themselves to prevent nutrients from drifting over to the undeserving. Alternatively, the natural flow of fluids over the surface of bacterial communities can wash away excess food before the freeloaders can indulge. (more…)

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