Noise is an issue in optical telecommunications. And findings means of controlling noise is key to physicists investigating light-emitting diodes or lasers. Now, an Italo-Iraqi team has worked on a particular type of light source, called the quantum dot light-emitting diode (QDLED). In a study published in EPJ D, Kais Al Namee from the National Institute of Optics, in Florence, Italy and colleagues, demonstrate that modulating bias current of the QDLED could lead to countering the noise.
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PITTSBURGH--Trips and stumbles too often lead to falls for amputees using leg prosthetics, but a robotic leg prosthesis being developed at Carnegie Mellon University promises to help users recover their balance by using techniques based on the way human legs are controlled.
Hartmut Geyer, assistant professor of robotics, said a control strategy devised by studying human reflexes and other neuromuscular control systems has shown promise in simulation and in laboratory testing, producing stable walking gaits over uneven terrain and better recovery from trips and shoves.
In a randomized clinical trial of more than 300 participants, researchers from Johns Hopkins and elsewhere have found that ranibizumab -- a drug most commonly used to treat retinal swelling in people with diabetes -- is an effective alternative to laser therapy for treating the most severe, potentially blinding form of diabetic retinal disease. Results of the government-sponsored study also show that the drug therapy carries fewer side effects than the currently used laser treatment.
Many recently developed pneumococcal serotyping methods detect the dominant serotype in a laboratory or field sample, but several fail to detect minor serotypes, according to a study published this week in PLOS Medicine. This investigation of 20 current methods, conducted by Catherine Satzke of the Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Victoria, Australia, and colleagues, indicates that a microarray analysis with culture amplification is a top-performing method, but a cheaper culture and latex sweep method represents a viable alternative.
Athens, Ga. - A University of Georgia researcher has found that low levels of vitamin D may limit the effectiveness of HIV treatment in adults.
Those with human immunodeficiency virus--commonly known as HIV--often struggle with declining health because their immune systems can't effectively respond to common pathogens. Their immune statuses, usually measured by CD4+T cells, normally improve when given HIV treatment.
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When corn prices increase, corn yield also increases. The response is one-third from better management practices and intensive use of land and two-thirds from additional planted acreage.
Changes in climate can lead to 7 to 12 percent reduction in corn yields under slow-warming scenarios to as much as 40 percent reduction under the rapid-warming scenarios.
Jülich, 17 November 2015 - The overheating of computer chips is a major obstacle to the development of faster and more efficient computers and mobile phones. One promising remedy for this problem could be a class of materials first discovered just a few years ago: topological insulators, which conduct electricity with less resistance and heat generation than conventional materials. Research on these materials is still in its early stages.
Scientists at the Energy Department's National Renewable Energy Laboratory (NREL) have demonstrated a way to significantly increase the efficiency of perovskite solar cells by reducing the amount of energy lost to heat.
A paper on the discovery, "Observation of a hot-phonon bottleneck in lead-iodide perovskites," was published online this week in the journal Nature Photonics. The research also will appear in the January print edition of the journal.
CHAMPAIGN, Ill. -- Even in an age of affluence and abundance in which round-the-clock consumerism and overspending are the norm, limits and constraints can still serve a purpose. According to new research co-written by a University of Illinois expert in new product development and marketing, resource scarcity actually translates into enhanced consumer product-use creativity.
A key issue with lithium ion batteries is aging. It significantly reduces their potential storage capacity. To date, very little is known about the causes of the aging effects. Scientists from the Department of Technical Electrochemistry and the Research Neutron Source FRM II at the Technical University of Munich (TUM) have now come a step closer to identifying the causes in their latest experiments.
The information revolution is synonymous with the traditional quest to pack more chips and increase computing power. This quest is embodied by the famous "Moore's law", which predicts that the number of transistors per chip doubles every couple of years and has held true for a remarkably long time. However, as Moore´s law approaches its limit, a parallel quest is becoming increasingly important.
Since the first laser was invented in 1960, they've always given off heat -- either as a useful tool, a byproduct or a fictional way to vanquish intergalactic enemies.
But those concentrated beams of light have never been able to cool liquids. University of Washington researchers are the first to solve a decades-old puzzle -- figuring out how to make a laser refrigerate water and other liquids under real-world conditions.
WASHINGTON - The amount of data that flows over the internet has exploded in the last decade. Whether people are watching cat videos, streaming movies, or uploading vacation photos to social media sites, they are demanding ever higher performance from the optical networks that are the physical foundation of the World Wide Web.
A team of Australian engineers has proven -- with the highest score ever obtained -- that a quantum version of computer code can be written, and manipulated, using two quantum bits in a silicon microchip. The advance removes lingering doubts that such operations can be made reliably enough to allow powerful quantum computers to become a reality.
The result, obtained by a team at Australia's University of New South Wales (UNSW) in Sydney, appears today in the international journal, Nature Nanotechnology.
MANHATTAN, KANSAS -- A new Kansas State University study finds that the over-tapping of the High Plains Aquifer's groundwater beyond the aquifer's recharge rate peaked in 2006. Its use is projected to decrease by roughly 50 percent in the next 100 years.