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Keen sense of touch allows bats to fly with breathtaking precision -- ScienceDaily Scientists from Johns Hopkins University, as well as Columbia University and the University of Maryland, determined how the sense of touch plays a key role in powered flight. In a paper published April 30 in the journal Cell Reports , they show how sensory receptors in bat wings send information about airflow to neurons in the brain, enabling the bat to make split-second flight control adjustments. "Until now no one had investigated the sensors on the bat's wing, which allow it to serve as more than a propeller, a flipper, an airplane wing or any simple airfoil," said Johns Hopkins neuroscientist Cynthia F. Moss, one of the senior authors and a professor in the Department of Psychological and Brain Sciences in the Krieger School of Arts and Sciences. "These findings can inform more broadly how organisms use touch to guide movement." Moss and the team studied the big brown bat, a c...

Brain scan reveals out-of-body illusion -- ScienceDaily The sense of owning one's body and being located somewhere in space is so fundamental that we usually take it for granted. To the brain, however, this is an enormously complex task that requires continuous integration of information from our different senses in order to maintain an accurate sense of where the body is located with respect to the external world. Studies in rats have shown that specific regions of the brain contain GPS-like 'place cells' that signal the rat's position in the room -- a discovery that was awarded the 2014 Nobel Prize in Physiology or Medicine. To date, however, it remains unknown how the human brain shapes our perceptual experience of being a body somewhere in space, and whether the regions that have been identified in rats are involved in this process. In a new study, published in the scientific journal Current Biology , the scientists created an out-of-body illusion in fifteen healthy...

Scientists discover key driver of human aging: May lead to slowing or reversing aging process -- ScienceDaily In the study, scientists at the Salk Institute and the Chinese Academy of Science found that the genetic mutations underlying Werner syndrome, a disorder that leads to premature aging and death, resulted in the deterioration of bundles of DNA known as heterochromatin. The discovery, made possible through a combination of cutting-edge stem cell and gene-editing technologies, could lead to ways of countering age-related physiological declines by preventing or reversing damage to heterochromatin. "Our findings show that the gene mutation that causes Werner syndrome results in the disorganization of heterochromatin, and that this disruption of normal DNA packaging is a key driver of aging," says Juan Carlos Izpisua Belmonte, a senior author on the paper. "This has implications beyond Werner syndrome, as it identifies a central mechanism of aging--heterochromatin diso...

'Dead zones' found in Atlantic open waters: Moving west, could lead to mass fish kills -- ScienceDaily Dead zones are areas of the ocean depleted of oxygen. Most marine animals, like fish and crabs, cannot live within these regions, where only certain microorganisms can survive. In addition to the environmental impact, dead zones are an economic concern for commercial fishing, with very low oxygen concentrations having been linked to reduced fish yields in the Baltic Sea and other parts of the world. "Before our study, it was thought that the open waters of the North Atlantic had minimum oxygen concentrations of about 40 micromol per litre of seawater, or about one millilitre of dissolved oxygen per litre of seawater," says lead-author Johannes Karstensen, a researcher at GEOMAR, the Helmholtz Centre for Ocean Research Kiel, in Kiel, Germany. This concentration of oxygen is low, but still allows most fish to survive. In contrast, the minimum levels of oxygen now measu...

No Hogwarts invitation required: Invisibility cloaks move into the real-life classroom -- ScienceDaily Real-life invisibility cloaks do exist, in a manner of speaking: researchers have engineered systems that bend light around an object, shielding it from detection. But most are very tiny and only work at very small wavelength ranges, rendering them less impressive to the average observer. Now, a group of researchers from the Karlsruhe Institute of Technology (KIT), in Karlsruhe, Germany, has developed a portable invisibility cloak that can be taken into classrooms and used for demonstrations. It can't hide a human, but it can make small objects disappear from sight without specialized equipment. Scientists hoping to divert light around an object to render it invisible must find a way to compensate for the increased distance the light must now travel. On a road trip, you might solve this problem by changing your speed. If you had planned to take the rutted scenic road directly over...

Eagle Nebula: The Pillars of Creation revealed in 3-D -- ScienceDaily The original NASA/ESA Hubble Space Telescope image of the famous Pillars of Creation was taken two decades ago and immediately became one of its most famous and evocative pictures. Since then, these billowing clouds, which extend over a few light-years,* have awed scientists and the public alike. The jutting structures, along with the nearby star cluster, NGC 6611, are parts of a star formation region called the Eagle Nebula, also known as Messier 16 or M16. The nebula and its associated objects are located about 7000 light-years away in the constellation of Serpens (The Serpent). The Pillars of Creation are a classic example of the column-like shapes that develop in the giant clouds of gas and dust that are the birthplaces of new stars. The columns arise when immense, freshly formed blue-white O and B stars give off intense ultraviolet radiation and stellar winds that blow away less dense materials from their vicini...

Challenging work tasks may have an upside for the brain -- ScienceDaily "Our study is important because it suggests that the type of work you do throughout your career may have even more significance on your brain health than your education does," said study author Francisca S. Then, PhD, with the University of Leipzig in Germany. "Education is a well-known factor that influences dementia risk." For the study, 1,054 people over the age of 75 were given tests that measured their memory and thinking abilities every one-and-a-half years for eight years. The researchers also asked the participants about their work history and categorized the tasks they completed into three groups: executive, verbal and fluid. Examples of executive tasks are scheduling work and activities, developing strategies and resolving conflicts. Examples of verbal tasks are evaluating and interpreting information and fluid tasks were considered to be those which included selective attention and an...

How babies' lives were saved by 3-D printing -- ScienceDaily Three babies all had the same life-threatening condition: a terminal form of tracheobronchomalacia, which causes the windpipe to periodically collapse and prevents normal breathing. There was no cure and life-expectancies were grim. The three boys became the first in the world to benefit from groundbreaking 3D printed devices that helped keep their airways open, restored their breathing and saved their lives at the University of Michigan's C.S. Mott Children's Hospital. Researchers have closely followed their cases to see how well the bioresorable splints implanted in all three patients have worked, publishing the promising results in today's issue of Science Translational Medicine . "These cases broke new ground for us because we were able to use 3D printing to design a device that successfully restored patients' breathing through a procedure that had never been done before," says senior author ...

Making robots more human: Wearable sensors read human facial expressions -- ScienceDaily Nae-Eung Lee and colleagues note that one way to make interactions between people and robots more intuitive would be to endow machines with the ability to read their users' emotions and respond with a computer version of empathy. Most current efforts toward this goal analyze a person's feelings using visual sensors that can tell a smile from a frown, for example. But these systems are expensive, highly complex and don't pick up on subtle eye movements, which are important in human expression. Lee's team wanted to make simple, low-cost sensors to detect facial movements, including slight changes in gaze. The researchers created a stretchable and transparent sensor by layering a carbon nanotube film on two different kinds of electrically conductive elastomers. They found it could tell whether subjects were laughing or crying and where they were looking. In addition to applications in ...

Artificial photosynthesis could help make fuels, plastics and medicine -- ScienceDaily Peidong Yang, Michelle C. Y. Chang, Christopher J. Chang and colleagues note that plants use photosynthesis to convert sunlight, water and carbon dioxide to make their own fuel in the form of carbohydrates. Globally, this natural process harvests 130 Terawatts of solar energy. If scientists could figure out how to harness just a fraction of that amount to make fuels and power industrial processes, they could dramatically cut our reliance on fossil fuels. So, Yang, Michelle Chang and Christopher Chang's teams wanted to contribute to these efforts. The groups developed a stand-alone, nanowire array that captures light and with the help of bacteria, converts carbon dioxide into acetate. The bacteria directly interact with light-absorbing materials, which the researchers say is the first example of "microbial photoelectrosynthesis." Another kind of bacteria then transforms the acetate into ...