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The Flowing Sands of Mars

By Guest PostMay 13, 2012ScienceAntarctica, caltech, craters, digital terrain model, doug mccuistion, dtm, earth, flowing sands, geological processes, gullies, high speed winds, hirise camera, jean philippe avouac, mars, martian equator, martian landscape, martian surface, mro, NASA, nathan bridges, nili patera, red planet, rocks on mars, sand dunes, sarah mattson, valleys

Sand dunes on Mars move not unlike those on Earth, despite a much thinner atmosphere and weaker winds, as revealed by images taken with the UA-led HiRISE camera.

NASA’s Mars Reconnaissance Orbiter, or MRO, has revealed that movement in sand dune fields on the Red Planet occurs on a surprisingly large scale, about the same as in dune fields on Earth.

This is unexpected because Mars has a much thinner atmosphere than Earth is only about 1 percent as dense, and its high-speed winds are less frequent and weaker than Earth’s.

For years, researchers debated whether or not sand dunes observed on Mars were mostly fossil features related to past climate, rather than currently active. In the past two years, researchers using images from MRO’s High Resolution Imaging Science Experiment, or HiRISE, camera have detected and reported sand movement. (more…)

Insect Glands May Illuminate Human Fertilization Process

By Guest PostMay 12, 2012Health, Scienceallan spradling, bee, cellular physiology, egg, fertilization, fruit fly, gene, hr39, human, insect glands, jianjun sun, lrh 1, mammals, receptor protein, reproductive glands, secretion, secretion glands, sperm

Baltimore, MD — Insect glands are responsible for producing a host of secretions that allow bees to sting and ants to lay down trails to and from their nests. New research from Carnegie scientists focuses on secretions from glands in the reproductive tract that help sperm survive and guide the sperm on the trip to fertilize an egg. The gene that controls the development of these glands in fruit flies provides important information about gland development in all insects, as well as potential clues to similar human reproductive glands. Their work is published this month in Current Biology.

When a female fruit fly receives sperm from a male fruit fly, lubricating secretions in her reproductive tract activate the sperm, store it, and guide it to fertilization. Without the aid of these secretions, sperm would not make it to the eggs. Carnegie’s Allan Spradling and Jianjun Sun demonstrated that the gene in charge of regulating the development of fruit fly secretion glands is called Hr39. It encodes a steroid receptor protein. (more…)

The Success of Homo sapiens May Be Due to Spatial Abilities

By Guest PostMay 12, 2012Scienceenvironmental stress, homo sapiens, neanderthals, paleoanthropologist, spatial abilities

While the disappearance of Neanderthals remains a mystery, paleoanthropologists have an increasing understanding of what allowed their younger cousins, Homo sapiens, to conquer the planet. According to Ariane Burke, Professor in the Department of Anthropology at the Université de Montréal, the rapid dispersal of anatomically modern humans was not so much due to superior intelligence or improved hunting or gathering techniques, but rather to the creation of symbolic objects that allowed them to extend their social relations across vast territories. (more…)

Portable Diagnostics Designed To Be Shaken, Not Stirred

By Guest PostMay 12, 2012Scienceashutosh shastry, asymmetrical surface, audio speaker, blood, energy, hannah hickey, karl bohringer, lotus effect, lotus leaf, medical researcher, menlo park, Nanotechnology, portable diagnostics, rough surface, saliva, smartphone, todd duncombe, university of washington, vibration, vibration frequency, water sample, yegan erdem

As medical researchers and engineers try to shrink diagnostics to fit in a person’s pocket, one question is how to easily move and mix small samples of liquid.

University of Washington researchers have built and patented a surface that, when shaken, moves drops along certain paths to conduct medical or environmental tests.

“This allows us to move drops as far as we want, and in any kind of layout that we want,” said Karl Böhringer, a UW professor of electrical engineering and bioengineering. The low-cost system, published in a recent issue of the journal Advanced Materials, would require very little energy and avoids possible contamination by diluting or electrifying the samples in order to move them. (more…)

You’re Beautiful, Vesta

By Guest PostMay 11, 2012Sciencedawn mission, meteorites from vesta, mineral data, protoplanet, protoplanet vesta, vesta

NASA’s UCLA-led Dawn mission shows protoplanet’s surprising surface

When UCLA’s Christopher T. Russell looks at the images of the protoplanet Vesta produced by NASA’s Dawn mission, he talks about beauty as much as he talks about science. (more…)

UCLA Scientists Unlock Mystery of How ‘Handedness’ Arises

By Guest PostMay 10, 2012Scienceachiral building blocks, achiral objects, chirality, handedness, lithographic triangular particles, mirror image phenomenon, molecular characteristic

The overwhelming majority of proteins and other functional molecules in our bodies display a striking molecular characteristic: They can exist in two distinct forms that are mirror images of each other, like your right hand and left hand. Surprisingly, each of our bodies prefers only one of these molecular forms. (more…)

Brighter, Smaller Probes to Uncover the Secret Lives of Proteins

By Guest PostMay 10, 20121 commentSciencebeta phase nanocrystals, geometry of nanocrystals, nanocrystals, upconverting nanocrystals

Berkeley Lab scientists create nanoparticle probes that may lead to a better understanding of diseases

Imagine tracking a deer through a forest by clipping a radio transmitter to its ear and monitoring the deer’s location remotely. Now imagine that transmitter is the size of a house, and you understand the problem researchers may encounter when they try to use nanoparticles to track proteins in live cells. (more…)

Scientists Measure Communication between Stem Cell-Derived Motor Neurons, Muscle Cells

By Guest PostMay 10, 2012Science: walking, amyotrophic lateral sclerosis, bennett g novitch, breathing, communication, electrode, genetic mutation, joy umbach, lou gehrigs disease, motor function, motor neuron, muscle cells, neurodegenerative diseases, neurological disorder, spinal muscular atrophy, synaptic activity, vitro system

In an effort to identify the underlying causes of neurological disorders that impair motor functions such as walking and breathing, UCLA researchers have developed a novel system to measure communication between stem cell–derived motor neurons and muscle cells in a Petri dish.

The study provides an important proof of principle that functional motor circuits can be created outside the body using these neurons and cells and that the level of communication, or synaptic activity, between them can be accurately measured by stimulating the motor neurons with an electrode and then tracking the transfer of electrical activity into the muscle cells to which the neurons are connected. (more…)

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