Daily Archives: February 9, 2010
Micro Solar Cells Handle More Intense Sunlight
Microcell: The solar cells made by Semprius are 600 micrometers on each side and can be combined with high-power optics. The cell itself (the black square at center) is mounted atop a ceramic base with electrical contacts on each side. Credit: Semprius)
Cells absorb sunlight concentrated 1,000 times without cooling.
A startup company hopes to bring down the cost of generating power with concentrated sunlight by using microscale solar cells that can utilize twice as much light as other panels, without the need for expensive optics or cooling systems. Panels made from the tiny cells, which the Durham, NC-based company Semprius developed using a novel microprinting technology, also offer significant savings on materials costs. In late January, the company announced a joint agreement with Siemens to develop demonstration systems based on its technology. Semprius plans to begin volume production of the modules in 2013.
Adding concentrating lenses to solar panels increases the amount of electricity they can produce. But photovoltaic concentrators add a great deal of expense to a solar installation. The optical systems themselves are expensive and bulky–the larger a cell, the larger its paired lens must be. More intense light also means that more performance-degrading heat must be dissipated using heat sinks or fans. Although the cost is partly offset by the efficiency of high-concentration photovoltaics, it limits the potential power of such concentrator systems. The two major suppliers of concentrated solar modules, Amonix and Emcore, both sell systems based on conventional-size cells that operate under 500 times concentration sunlight with costly cooling systems.
Semprius’s solar modules contain arrays of square cells that measure just 600 micrometers on each side. These cells have three semiconducting layers–each of which is based on gallium arsenide and absorbs a different band of sunlight–and they are made using a combination of chemical etching and printing, which means fewer raw materials are wasted. They can operate under sunlight concentrated 1,000 times using cheap optical systems. According to the National Renewable Energy Laboratories, the efficiency of the resulting modules ranges from 25 to 35 percent and they can provide electricity for about 10 cents a kilowatt hour. The company expects the final costs, including installation, to be $2 to $3 per watt.
Last year, a study by researchers at Sandia National Laboratories in Albuquerque, NM, suggested that microscale solar cells might offer various cost and design advantages. “You reduce the amount of semiconductor you need, so there can be a big cost savings,” says Gregory Nielson, head scientist on the Sandia project. “And you can do things with the optics that you can’t do with larger cells.”
Smaller solar cells are more efficient at dissipating heat. “When the cells are below a millimeter, they reject the heat so efficiently they’ll be just as cool as a one-sun panel,” without the need for any cooling systems, says Nielson. This is because the tiny cells have a much greater percentage of total area given up to heat-diffusing edges.
Article continues – http://www.technologyreview.com/energy/24504/
Searching for Disease Clues in Genetic Diversity
Melting pot: A new effort to study genetic diversity in Latin Americans, specifically in Mexico, could shed light on diseases, such as type 2 diabetes, that strike this group disproportionately. Credit: Jeinny Solis S.
Research on the Mexican genome could broaden the scope of personalized medicine.
By Emily Singer
Over the last few years, scientists have discovered hundreds of genetic variants linked to disease. But the vast majority of that research has focused on people of European, Asian, and African descent. A new effort to catalog genetic diversity among people in Mexico–who along with other Latin Americans have a unique ancestry–could shed light on diseases that affect these groups disproportionately, and on why some drugs may work more or less effectively in these populations. The research might also help uncover rare genetic variants responsible for a significant portion of the genetic risk of disease.
“If personalized medicine is going to become a global phenomenon, then scientists need to understand the genomes of all the world’s populations,” says Gerardo Jimenez-Sanchez, former director of the National Institute of Genomic Medicine, in Mexico. (The institute, created in 2004, and known by the acronym INMEGEN, is analogous to the U.S. National Human Genome Research Institute.)
Hispanics are a relatively young–about 500-year-old–amalgam of three major continental groups–European, Native American, and African–and make up about 15 percent of the world’s population. “Within that area is so much environmental and genetic variability that you can really leverage the intrinsic diversity to your scientific advantage,” says Esteban Burchard, a physician and scientist at the University of California, San Francisco. For example, if a certain disease is much more common in one ancestral group, scientists need only screen the DNA inherited from that group in a person of mixed ancestry. That significantly cuts the amount of DNA that must be examined in order to find genes linked to the disease.
Researchers hope to capture some of that diversity with the recently announced Slim Initiative for Genomic Health, a $65 million partnership between the Broad Institute, a genomics research institute in Cambridge, MA, and the Carlos Slim Health Institute, a nonprofit based in Mexico City. The research will focus on the genetic basis of type 2 diabetes in Mexican and Latin American populations, as well as on the genomics of cancer worldwide.
“Most work on diabetes was done in European populations, and much will be learned from looking at other populations,” says Eric Lander, director of the Broad. “Even if the fundamental mechanisms are the same in all populations, particular genetic variants will be different, so it will be easier to find some genes in some populations.” Type 2 diabetes occurs at a particularly high frequency in Latin American populations, and “there’s reason to think that the Native American contribution to the gene pool has some effect,” he adds. While the specific details of the initiative are still being planned, it will encompass both gene sequencing and microarray-based studies. Much of the initial work will be done at the Broad.
Article Continues – http://www.technologyreview.com/biomedicine/24496/
Designing a highly reliable small & medium business network
Flickr: Jason Fischer
By Brian Hill
If you’ve ever been an IT manager for a small business network, you’re aware of one simple fact: small and medium business (SMB) networks are generally something of a mess. Typically, they’re organically grown and built off of consumer-class hardware. Network management tools are usually non-existent, documentation is erratic, and redundancy is totally absent. The end result is that the typical SMB network is a virtual fireball, with the network admin running around carrying a pail and trying to extinguish the fires.
What tends to happen, eventually, is that one of these outages becomes damaging enough to cause management to demand a better infrastructure. There’s always a catch, however, and in most cases it’s money. Luckily, you can build a highly reliable network without breaking the bank, as long as you focus on eliminating high-impact, single points of failure.
In this article, I’ll explain how to create a highly available SMB network. In order to be as vendor-neutral as possible, I will try to avoid specific technologies, and will instead lay out some goals, along with common methods for meeting those goals. For similar reasons, I will not detail exact costs, but where possible, I’ll give you relative costs. Finally, I won’t include virtualization options in this article, and will instead focus on standard client-server infrastructures. While virtualization can allow for very highly available infrastructures, a fully virtualized infrastructure is beyond the grasp of most small to medium sized businesses.
Client design: rapid recovery
Before discussing the best options for availability on the client side, we should point out one highly important fact: Client failures are not generally high-impact failures. One client machine failing will typically only affect one user. While there are occasions (such as the failure of a major executive’s system) that break this rule, in general, client redundancy is not worth the expense. Instead of redundancy, the focus for client systems should be on rapid recovery.
Enabling rapid recovery of client systems involves three major components: commodity hardware, network storage of user data, and disk imaging. Essentially, the goal is to be able to replace the user’s system as quickly as possible. If you use commodity hardware, it becomes easy to maintain shelf spares that you can quickly swap for a defective system in the case of hardware failure. For major software failures, maintaining an up-to-date base disk image allows you to rapidly redeploy a working image onto the machine. In both cases, however, user data must be housed on the network, or data loss will occur.
The details on how to implement this will be dependent on your chosen OS, but the basic principles are the same. Where possible, when making tradeoffs, try to choose the option that reduces downtime as much as you can. For example, to image a system you could use a basic image with just the OS, and use a software installation service to individually install applications once the machine is online. Alternately, you could use a complete image with the OS and all of the apps preinstalled. In general, the second option is going to be faster, but has the disadvantage of being harder to maintain. If reducing downtime is your primary goal, however, using complete disk images is the obvious choice.
Laptops, however, can complicate the client design. Since laptops are not always connected to the network, using entirely network-based data storage is not acceptable for these users. The solution, generally, is to use a caching mechanism. For example, on Windows systems, you can use offline files to handle the caching of raw data files, and allow roaming profiles to be cached to handle user profile issues.
Next, examine your cable plant. If you are installing new cable, it’s generally a good idea to pull double the number of cables for each drop. There are a few reasons for this. First, if you have some kind of major failure with a cable (rats chewing through insulation are not unheard of), you can quickly switch off to a different jack. Second, if at some point in the future you decide to use NIC teaming to increase the speed or reliability of the system’s network connection, you will have that option. Also, most of the cost of running cable is in labor, so it is generally very cheap to start with two cables for a drop, but very expensive to go back and add a second one later.
Switching design basics
On the switching side, your key considerations are:
- Whether or not to use a collapsed core
- Core redundancy and trunk redundancy
- Switch choices and load out
- Spanning Tree design
- L3 switching model
For the base design, for a network of this size, you are typically looking at a collapsed core design, similar to the one shown below. This means that all of the real switching complexity is concentrated at the core.
Article Continues – http://arstechnica.com/business/news/2010/02/designing-a-highly-reliable-small-medium-business-network.ars
Scientists Identify First Genetic Variant Linked to Biological Aging in Humans
Scientists announced they have identified for the first time definitive variants associated with biological ageing in humans. (Credit: iStockphoto/Anne De Haas)
Scientists announced they have identified for the first time definitive variants associated with biological ageing in humans. The team analyzed more than 500,000 genetic variations across the entire human genome to identify the variants which are located near a gene called TERC.
The study in Nature Genetics published by researchers from the University of Leicester and King’s College London, working with University of Groningen in the Netherlands, was funded by The Wellcome Trust and the British Heart Foundation.
British Heart Foundation Professor of Cardiology at the University of Leicester Professor Nilesh Samani, of the Department of Cardiovascular Sciences, who co-led the project explained that there are two forms of ageing — chronological ageing i.e. how old you are in years and biological ageing whereby the cells of some individuals are older (or younger) than suggested by their actual age.
He said: “There is accumulating evidence that the risk of age-associated diseases including heart disease and some types of cancers are more closely related to biological rather than chronological age.
“What we studied are structures called telomeres which are parts of one’s chromosomes. Individuals are born with telomeres of certain length and in many cells telomeres shorten as the cells divide and age. Telomere length is therefore considered a marker of biological ageing.
“In this study what we found was that those individuals carrying a particular genetic variant had shorter telomeres i.e. looked biologically older. Given the association of shorter telomeres with age-associated diseases, the finding raises the question whether individuals carrying the variant are at greater risk of developing such diseases”
Professor Tim Spector from King’s College London and director of the TwinsUK study, who co-led this project, added:
“The variants identified lies near a gene called TERC which is already known to play an important role in maintaining telomere length. What our study suggests is that some people are genetically programmed to age at a faster rate. The effect was quite considerable in those with the variant, equivalent to between 3-4 years of ‘biological aging” as measured by telomere length loss. Alternatively genetically susceptible people may age even faster when exposed to proven ‘bad’ environments for telomeres like smoking, obesity or lack of exercise — and end up several years biologically older or succumbing to more age-related diseases. “
The paper, will be published online in Nature Genetics on 07 February 2010.
Story Source:
Adapted from materials provided by University of Leicester, via EurekAlert!, a service of AAAS.
http://www.sciencedaily.com/releases/2010/02/100207145351.htm
US military may enlist Omega-3s to boost performance but why wait?
“An army marches on its stomach.” This advice, from French military adventurer Napoleon, seems to have impressed the US military which is considering fortifying troops’ rations with omega-3 fatty acids. What is it waiting for?
Discovered 80 years ago, there’s a wealth of science supporting the health benefits of long-chain omega-3 fatty acids DHA and EPA. From heart health to brain function and from combating depression to safeguarding pregnancy, eye health and cutting the risk of cancers, omega-3’s health benefits seem legion.
The most widely available source of EPA and DHA is oily fish such as salmon, herring, mackerel, anchovies and sardines. But new sources from krill oil and, for ALA, from vegetables are also becoming popular.
Nutritional armour
Dubbed nutritional armour, omega-3s could enhance significantly battlefield performance, according to many scientists including at least one former US surgeon general, Richard Carmona. Key benefits focus on improving soldiers’ stress resilience and general wellness.
Tellingly, the military applications of omega-3s were explored last December at a conference entitled Nutritional armor for the warfighter: can omega-3s enhance stress resilience, wellness and military performance? staged at the Samueli Institute based in Alexandria, Virginia.
It’s not just combat performance that could be improved by omega-3s. Some military dietitians believe they could help to cut medical bills running into millions of $s.
Omega 3s have been shown to benefit four of the top five ailments or conditions for which troops receive hospital treatment. Those include: Depression, post traumatic stress disorder, surgical complications and, for female soldiers, pregnancy. They are also believed to speed recovery from traumatic brain injury (TBI).
Military planners are particularly concerned about the high rates of suicide and depression together with physical and mental stress associated with combat in Iraq and Afghanistan. At least 334 members of the military services committed suicide last year compared with 297 killed in Afghanistan and 144 who died in Iraq, according to Department of Defense (DOD) statistics.
So why is the US military so slow to adopt health ingredients that could sharpen military performance and axe millions of $s from its medical bills?
True, the Department of Defense’s Dietary Supplements Committee is talking to scientists at the Samueli Institute and elsewhere about the use of omega-3s. But how much more talk is needed?
Widespread adoption
If the military approved the rapid and widespread adoption of omega-3 fortification, how many lives broken by depression could be mended more quickly? How many suicides avoided? How many taxpayers’ $ are wasted on medical treatment that could be saved?
The path ahead is clear: The US military should fortify active service personnel’s rations with omega 3s as soon as possible. To achieve that would require the removal of a directive that prevents the distribution of pharmaceuticals or wellness products via the military food supply. But that would be a small price to pay in order to achieve a great good.
It is a decision growing numbers of US military personnel are making for themselves. Increasing numbers are taking omega-3 supplements to benefit their health. Their example should be heeded by their masters in the Pentagon and others. The British military, for example, has no plans to consider using omega-3s.
Meanwhile, if omega-3s can deliver such stunning benefits on the battlefield and in the hospital ward, what other health supplements could be enlisted?
Topping the list for investigation should be prebiotic and probiotics. How much longer can military planners and others fail to act on the wealth of scientific evidence?
It’s not recorded whether Napoleon liked oily fish. But, if he suspected their military benefits, he would not have been slow to use them. Who knows – the battle of Waterloo, won – only just – by British and Prussian allies, may have had a different outcome.
Mike Stones writes about health ingredients, food and farming.
India Says it “Cannot Rely” on Biased UN Climate Panel, Forms National Institute of Himalayan Glaciology
Indian officials say that their nation “cannot rely” on the UN’s biased climate research. They have formed an independent research panel that will monitor the health of Himalayan glaciers and conduct climate studies. (Source: NASA)
Indian climate panel looks to offer independent insight
India, the world’s second most populous nation and an emerging research powerhouse, announced last week that it was establishing its own independent climate panel to investigate climate change
. Indian government officials said that they “cannot rely” on the the United Nation’s International Panel on Climate Change in light of recent errors.
India’s Environment Minister, Jairam Ramesh, announced the new panel on Wednesday evening. The new panel will be named the National Institute of Himalayan Glaciology. Its chief goal will be to monitor the health of the world’s “third ice cap”, and form an “Indian IPCC” to use “climate science” to offer analysis more solidly founded in unbiased observation.
Describes Mr. Ramesh, “There is a fine line between climate science and climate evangelism. I am for climate science. I think people misused [the] IPCC report, [the] IPCC doesn’t do the original research which is one of the weaknesses… they just take published literature and then they derive assessments, so we had goof-ups on Amazon forest, glaciers, snow peaks.”
He continues, “I respect the IPCC but India is a very large country and cannot depend only on [the] IPCC and so we have launched the Indian Network on Comprehensive Climate Change Assessment (INCCA).”
The move marks a major snub for the IPCC and its Indian chief, Rajendra Pachauri. As is alluded to in Mr. Ramesh’s remarks, over the last month Mr. Pachauri has been under fire for a retracted study that claimed the Himalayan Glaciers would melt by 2035.
Mr. Pachauri, who holds a doctorate in economics but no formal climate training, has been a controversial figure, suggesting that people worldwide give up luxuries such as meat to fight climate change despite reportedly living an affluent lifestyle personally. Nonetheless, Mr. Pachauri does have powerful supporters — as evidenced by the 2007 Nobel Peace Prize
, which he received along with fellow amateur researcher Al Gore.
Mr. Ramesh was critical of Mr. Pachauri’s recently retracted report, stating that it “was clearly out of place and didn’t have any scientific basis.”
The new National Institute of Himalayan Glaciology will be based in Dehradun, Uttarakhand and will publish its first climate survey in November. The survey will track glaciers in India, Pakistan, Nepal and Bhutan.
More scientific analysis on as significant a topic as understanding our planet is certainly a great idea and India’s desire to avoid reliance on biased climate research sources is commendable. One can only hope that they thoroughly examine past historical and geological evidence, which heavily points to cyclic climate changes independent of human influence. Recent studies have shown that the Earth may balance out what minimal atmospheric effects humans have, leaving solar activity as the primary driving factor of any changes in our planet’s climate.
Did Bacteria Developed Into More Complex Cells Much Earlier in Evolution Than Thought?
Artist’s rendering of cell structure. New research explains how mitochondria — the power house of human and other cells, which provide complex eukaryotic cells with energy and ability to produce, divide and move — were thought to have evolved about 2000 million years ago from primitive bacteria. (Credit: iStockphoto/Sebastian Kaulitzki)
Monash University biochemists have found a critical piece in the evolutionary puzzle that explains how life on Earth evolved millions of centuries ago.
The team, from the School of Biomedical Sciences, has described the process by which bacteria developed into more complex cells and found this crucial step happened much earlier in the evolutionary timeline than previously thought.
Team leader and ARC Federation Fellow Trevor Lithgow said the research explained how mitochondria — the power house of human and other cells, which provide complex eukaryotic cells with energy and ability to produce, divide and move — were thought to have evolved about 2000 million years ago from primitive bacteria.
“We have now come to understand the processes that drove cell evolution. For some time now the crux of this problem has been to understand how eukaryotes first came to be. The critical step was to transform small bacteria, passengers that rode within the earliest ancestors of these cells, into mitochondria, thereby beginning the evolution of more complex life-forms,” Professor Lithgow said.
The team found that the cellular machinery needed to create mitochondria was constructed from parts pre-existing in the bacterium. These parts did other jobs for the bacterium, and were cobbled together by evolution to do something new and more exciting.
“Our research has crystallised with work from other researchers around the world to show how this transformation happened very early on — that the eukaryotes were spawned by integrating the bacterium as a part of themselves. This process jump-started the evolution of complex life much more rapidly than was previously thought.”
The research consisted of two components, the first used computers to read, compare and understand DNA sequences. From this, experiments were designed to do actual laboratory testing using a bacterium that is the closest living relative to the original ancestor of the mitochondria.
The research was published in the journal Science.
Professor Lithgow said the latest findings were only made possible due to a gradual gathering of evidence within the scientific community and recent developments in genome sequencing. “We can now “read” with great care and insight genome sequences — the complete DNA sequence of any organism. From these sequences we find tell-tale clues to the past. Our findings are relevant to all species, including the evolution of humans,” Professor Lithgow said.
“It continues to amaze that this theory, proposed in the century before the advent of molecular investigations, is so accurate on a molecular scale. This improved understanding is directly relevant to the big picture timeline for the evolution of life.”
Professor Lithgow said the findings will be regarded by some scientists as controversial as many have long-held views on the process of evolution as a tinkerer. “This will surprise and may even spark debate. However our research compliments the basic rules of life. Even at the molecular level, the rules of the game are the same. Evolution drives biology to more and more complex forms,” Professor Lithgow said.
Story Source:
Adapted from materials provided by Monash University.
Journal Reference:
- Felicity Alcock, Abigail Clements, Chaille Webb, and Trevor Lithgow. Tinkering Inside the Organelle. Science, 2010; 327 (5966): 649-650 DOI: 10.1126/science.1182129
http://www.sciencedaily.com/releases/2010/02/100205091829.htm
Growing Cartilage: Bioactive Nanomaterial Promotes Growth of New Cartilage
3D illustration of the knee
3D illustration of the knee. Damaged cartilage can lead to joint pain and loss of physical function and eventually to osteoarthritis. (Credit: iStockphoto/Sebastian Kaulitzki)
Northwestern University researchers are the first to design a bioactive nanomaterial that promotes the growth of new cartilage in vivo and without the use of expensive growth factors. Minimally invasive, the therapy activates the bone marrow stem cells and produces natural cartilage. No conventional therapy can do this.
The results will be published online the week of Feb. 1 by the Proceedings of the National Academy of Sciences (PNAS).
“Unlike bone, cartilage does not grow back, and therefore clinical strategies to regenerate this tissue are of great interest,” said Samuel I. Stupp, senior author, Board of Trustees Professor of Chemistry, Materials Science and Engineering, and Medicine, and director of the Institute for BioNanotechnology in Medicine. Countless people — amateur athletes, professional athletes and people whose joints have just worn out — learn this all too well when they bring their bad knees, shoulders and elbows to an orthopaedic surgeon.
Damaged cartilage can lead to joint pain and loss of physical function and eventually to osteoarthritis, a disorder with an estimated economic impact approaching $65 billion in the United States. With an aging and increasingly active population, this is expected to grow.
“Cartilage does not regenerate in adults. Once you are fully grown you have all the cartilage you’ll ever have,” said first author Ramille N. Shah, assistant professor of materials science and engineering at the McCormick School of Engineering and Applied Science and assistant professor of orthopaedic surgery at the Feinberg School of Medicine. Shah is also a resident faculty member at the Institute for BioNanotechnology in Medicine.
Type II collagen is the major protein in articular cartilage, the smooth, white connective tissue that covers the ends of bones where they come together to form joints.
“Our material of nanoscopic fibers stimulates stem cells present in bone marrow to produce cartilage containing type II collagen and repair the damaged joint,” Shah said. “A procedure called microfracture is the most common technique currently used by doctors, but it tends to produce a cartilage having predominantly type I collagen which is more like scar tissue.”
The Northwestern gel is injected as a liquid to the area of the damaged joint, where it then self-assembles and forms a solid. This extracellular matrix, which mimics what cells usually see, binds by molecular design one of the most important growth factors for the repair and regeneration of cartilage. By keeping the growth factor concentrated and localized, the cartilage cells have the opportunity to regenerate.
Together with Nirav A. Shah, a sports medicine orthopaedic surgeon and former orthopaedic resident at Northwestern, the researchers implanted their nanofiber gel in an animal model with cartilage defects.
The animals were treated with microfracture, where tiny holes are made in the bone beneath the damaged cartilage to create a new blood supply to stimulate the growth of new cartilage. The researchers tested various combinations: microfracture alone; microfracture and the nanofiber gel with growth factor added; and microfracture and the nanofiber gel without growth factor added.
They found their technique produced much better results than the microfracture procedure alone and, more importantly, found that addition of the expensive growth factor was not required to get the best results. Instead, because of the molecular design of the gel material, growth factor already present in the body is enough to regenerate cartilage.
The matrix only needed to be present for a month to produce cartilage growth. The matrix, based on self-assembling molecules known as peptide amphiphiles, biodegrades into nutrients and is replaced by natural cartilage.
The National Institutes of Health and the company Nanotope supported the research.
Story Source:
Adapted from materials provided by Northwestern University.
Journal Reference:
- Samuel Stupp, Ramille Shah, Nirav Shah, Marc M. Del Rosario Lim, Caleb Hsieh and Gordon Nuber. Supramolecular Design of Self-assembling Nanofibers for Cartilage Regeneration. Proceedings of the National Academy of Sciences, Feb 1, 2010
http://www.sciencedaily.com/releases/2010/02/100201171649.htm
NASA, GM Take Giant Leap in Robotic Technology
Robonaut2 — or R2 for short — is the next generation dexterous robot, developed through a Space Act Agreement by NASA and General Motors. It is faster, more dexterous and more technologically advanced than its predecessors and able to use its hands to do work beyond the scope of previously introduced humanoid robots. (Credit: NASA)
Robonaut is evolving.
NASA and General Motors are working together to accelerate development of the next generation of robots and related technologies for use in the automotive and aerospace industries.
Engineers and scientists from NASA and GM worked together through a Space Act Agreement at the agency’s Johnson Space Center in Houston to build a new humanoid robot capable of working side by side with people. Using leading edge control, sensor and vision technologies, future robots could assist astronauts during hazardous space missions and help GM build safer cars and plants.
The two organizations, with the help of engineers from Oceaneering Space Systems of Houston, developed and built the next iteration of Robonaut. Robonaut 2, or R2, is a faster, more dexterous and more technologically advanced robot. This new generation robot can use its hands to do work beyond the scope of prior humanoid machines. R2 can work safely alongside people, a necessity both on Earth and in space.
“This cutting-edge robotics technology holds great promise, not only for NASA, but also for the nation,” said Doug Cooke, associate administrator for the Exploration Systems Mission Directorate at NASA Headquarters in Washington. “I’m very excited about the new opportunities for human and robotic exploration these versatile robots provide across a wide range of applications.”
NASA and General Motors have come together to develop the next generation dexterous humanoid robot. The robots — called Robonaut2 — were designed to use the same tools as humans, which allows them to work safely side-by-side humans on Earth and in space. Credit: NASA.
“For GM, this is about safer cars and safer plants,” said Alan Taub, GM’s vice president for global research and development. “When it comes to future vehicles, the advancements in controls, sensors and vision technology can be used to develop advanced vehicle safety systems. The partnership’s vision is to explore advanced robots working together in harmony with people, building better, higher quality vehicles in a safer, more competitive manufacturing environment.”
The idea of using dexterous, human-like robots capable of using their hands to do intricate work is not new to the aerospace industry. The original Robonaut, a humanoid robot designed for space travel, was built by the software, robotics and simulation division at Johnson in a collaborative effort with the Defense Advanced Research Project Agency 10 years ago. During the past decade, NASA gained significant expertise in building robotic technologies for space applications. These capabilities will help NASA launch a bold new era of space exploration.
“Our challenge today is to build machines that can help humans work and explore in space,” said Mike Coats, Johnson’s center director. “Working side by side with humans, or going where the risks are too great for people, machines like Robonaut will expand our capability for construction and discovery.”
NASA and GM have a long, rich history of partnering on key technologies, starting in the 1960s with the development of the navigation systems for the Apollo missions. GM also played a vital role in the development of the Lunar Rover Vehicle, the first vehicle to be used on the moon.
For more information on Robonaut and video, visit: http://robonaut.jsc.nasa.gov
Story Source:
Adapted from materials provided by NASA.
http://www.sciencedaily.com/releases/2010/02/100205110636.htm
How Well Do Scientists Understand How Changes in Earth’s Orbit Affect Long-Term Natural Climate Trends?
New research findings challenge the notion that scientists understand how changes in Earth’s orbit affect climate well enough for estimating long-term natural climate trends that underlie any anthropogenic climate change. (Credit: iStockphoto/Duncan Walker)
The notion that scientists understand how changes in Earth’s orbit affect climate well enough for estimating long-term natural climate trends that underlie any anthropogenic climate change is challenged by findings just published.
The new research was conducted by a team led by Professor Eelco Rohling of the University of Southampton’s School of Ocean and Earth Science hosted at the National Oceanography Centre, Southampton.
“Understanding how climate has responded to past change should help reveal how human activities may have affected, or will affect, Earth’s climate. One approach for this is to study past interglacials, the warm periods between glacial periods within an ice age,” said Rohling.
He continued: “Note that we have here focused on the long-term natural climate trends that are related to changes in Earth’s orbit around the Sun. Our study is therefore relevant to the long-term climate future, and not so much for the next decades or century.”
The team, which included scientists from the Universities of Tuebingen (Germany) and Bristol, compared the current warm interglacial period with one 400,000 years ago (marine isotope stage 11, or MIS-11).
Many aspects of the Earth-Sun orbital configuration during MIS-11 were similar to those of the current interglacial. For this reason, MIS-11 is often considered as a potential analogue for future climate development in the absence of human influence.
Previous studies had used the analogy to suggest that the current interglacial should have ended 2-2.5 thousand years ago. So why has it remained so warm?
According to the ‘anthropogenic hypothesis’, long-term climate impacts of man’s deforestation activities and early methane and carbon dioxide emissions have artificially held us in warm interglacial conditions, which have persisted since the end of the Pleistocene, about 11,400 years ago.
To address this issue, the researchers used a new high-resolution record of sea levels, which reflect ice volume. This record, which is continuous through both interglacials, is based on the ‘Red Sea method’ developed by Rohling.
Water passes between the Red Sea and the open ocean only through the shallow Strait of Bab-el-Mandab, which narrows as sea levels drop, reducing water exchange. Evaporation within the Red Sea increases its salinity, or saltiness, and changes the relative abundance of stable oxygen isotopes.
By analysing oxygen isotope ratios in tiny marine creatures called foraminiferans preserved in sediments that were deposited at the bottom of the Red Sea, the scientists reconstructed past sea levels, which were corroborated by comparison with the fossilised remains of coral reefs.
The researchers found that the current interglacial has indeed lasted some 2.0-2.5 millennia longer than predicted by the currently dominant theory for the way in which orbital changes control the ice-age cycles. This theory is based on the intensity of solar radiation reaching the Earth at latitude 65 degrees North on 21 June, the northern hemisphere Summer solstice.
But the anomaly vanished when the researchers considered a rival theory, which looks at the amount of solar energy reaching the Earth the same latitude during the summer months. Under this theory, sea levels could remain high for another two thousand years or so, even without greenhouse warming.
“Future research should more precisely narrow down the influence of orbital changes on climate,” said Rohling: “This is crucial for a better understanding of underlying natural climate trends over long, millennial timescales. And that is essential for a better understanding of any potential long-term impacts on climate due to man’s activities.”
The study was funded by the United Kingdom’s Natural Environment Council and the German Science Foundation.
Story Source:
Adapted from materials provided by National Oceanography Centre, Southampton (UK).
Journal Reference:
- Rohling et al. Comparison between Holocene and Marine Isotope Stage-11 sea-level histories. Earth and Planetary Science Letters, 2010; DOI: 10.1016/j.epsl.2009.12.054
http://www.sciencedaily.com/releases/2010/02/100205091825.htm
