Bionic leaf

Wed, 02/11/2015 - 12:27pm Elizabeth Cooney, HMS   Harvesting sunlight is a trick plants mastered more than a billion years ago, using solar energy to feed themselves from the air and water around them in the process we know as photosynthesis. Scientists have also figured out how to harness solar energy, using electricity from photovoltaic cells to yield hydrogen that can be later used in fuel cells. But hydrogen has failed to catch on as a practical fuel for cars or for power generation in a world designed around liquid fuels. Now scientists from a team spanning Harvard University’s Faculty of Arts and Sciences, Harvard Medical School and the Wyss Institute for Biologically Inspired Engineering have created a system that uses bacteria to convert solar energy into a liquid fuel. Their work integrates an “artificial leaf,” which uses a catalyst to make sunlight split water into hydrogen and oxygen, with a bacterium engineered to convert carbon dioxide plus hydrogen into the liquid fuel isopropanol. The findings are published Feb. 9 in PNAS. The co-first authors are Joseph Torella, a recent PhD graduate from the HMS Department of Systems Biology, and Christopher Gagliardi, a postdoctoral fellow in the Harvard Department of Chemistry and Chemical Biology. Pamela Silver, the Elliott T. and Onie H. Adams Professor of Biochemistry and Systems Biology at HMS and an author of the paper, calls the system a bionic leaf, a nod to the artificial leaf invented by the paper’s senior author, Daniel Nocera, the Patterson Rockwood Professor of Energy at Harvard University. “This is a proof of concept that you can have a way of harvesting solar energy and storing it in the form of a liquid fuel,” said Silver, who is a founding core faculty member of the Wyss. “Dan’s formidable discovery of the catalyst really set this off, and we had a mission of wanting to interface some kinds of organisms with the harvesting of solar energy. It was a perfect match.” Get more HMS news here. Silver and Nocera began collaborating two years ago, shortly after Nocera came to Harvard from MIT. They shared an interest in “personalized energy,” or the concept of making energy locally, as opposed to the current system, which in the example of oil means production is centralized and then sent to gas stations. Local energy would be attractive in the developing world. “It’s not like we’re trying to make some super-convoluted system,” Silver said. “Instead, we are looking for simplicity and ease of use.” In a similar vein, Nocera’s artificial leaf depends on catalysts made from materials that are inexpensive and readily accessible. “The catalysts I made are extremely well adapted and compatible with the growth conditions you need for living organisms like a bacterium,” Nocera said. In their new system, once the artificial leaf produces oxygen and hydrogen, the hydrogen is fed to a bacterium called Ralstonia eutropha. An enzyme takes the hydrogen back to protons and electrons, then combines them with carbon dioxide to replicate—making more cells. Next, based on discoveries made earlier by Anthony Sinskey, professor of microbiology and of health sciences and technology at MIT, new pathways in the bacterium are metabolically engineered to make isopropanol. “The advantage of interfacing the inorganic catalyst with biology is you have an unprecedented platform for chemical synthesis that you don’t have with inorganic catalysts alone,” said Brendan Colón, a graduate student in systems biology in the Silver lab and a co-author of the paper. “Solar-to-chemical production is the heart of this paper, and so far we’ve been using plants for that, but we are using the unprecedented ability of biology to make lots of compounds.” The same principles could be employed to produce drugs such as vitamins in small amounts, Silver said. The team’s immediate challenge is to increase the bionic leaf’s ability to translate solar energy to biomass by optimizing the catalyst and the bacteria. Their goal is 5 percent efficiency, compared to nature’s rate of 1 percent efficiency for photosynthesis to turn sunlight into biomass. “We’re almost at a 1 percent efficiency rate of converting sunlight into isopropanol,” Nocera said. “There have been 2.6 billion years of evolution, and Pam and I working together a year and a half have already achieved the efficiency of photosynthesis.” Source: Harvard Medical School

New flow cell-powered Quant F supercar promises 1,000 hp, 500 miles of range

The new Quant F will make its debut at the 2015 Geneva Motor Show in March (Photo: C.C. Weiss/Gizmag) Image Gallery (15 images) Nunzio La Vecchia is back, baby! And at this year's Geneva Motor Show, he's pitching an even more extraordinary, updated version of his flow cell supercar, the Nanoflowcell Quant F. La Vecchia claims that the updated car's flow battery can power the motor to a tune of 1,000 hp (746 kW) and 500 miles (805 km). We're still loath to believe all the hype, but this high-tech red sports car simply can't be ignored. When we saw Nanoflowcell's presentation at last year's Geneva Motor Show, we weren't quite sure what to make of the start-up. But between its seemingly too-good-to-be-true claims and the flashy showman at its helm (that's La Vecchia), we were leaning toward unwavering skepticism. That hasn't really changed in the past year, and the fact that Nanoflowcell's suspect numbers have fattened up even more doesn't make us any more hopeful. Still, the Quant F is a very interesting concept car, if nothing else. The Quant E, formerly called the Quant e-Sportlimousine, at the 2014 Geneva Motor Show (Photo: C.C. Weiss/Gizmag) Nanoflowcell seems to have realized that "Nanoflowcell Quant e-Sportlimousine" (that's nanoFLOWCELL QUANT e-Sportlimousine, if we're being true to company copy) was about the least catchy name a groundbreaking supercar could possibly have. Now, it's calling last year's concept the "Quant E" and this year's the "Quant F". That naming structure makes sense not only in successive lettering/prototype format, but also in light of Nanoflowcell's flow cell electricity generation. A "Quant G" might run into some problems next year, though. As you might recall from last year's Quant E, Nanoflowcell is hyping an entirely different type of vehicular energy storage technology, the likes of which are usually only seen in university research papers. The system produces electricity from two ionic fluids stored in 250-liter (66-US gal) tanks (previously 200-liter tanks). "Instead of using hydrogen and oxygen as in a conventional fuel cell, we work with two ionic fluids – one with a positive charge and one with a negative charge," explains La Vecchia. "We are only in the initial phase of our development work. The fact that we store the energy for our drive in a fluid provides us with enormous advantages over systems employed to date in the field of electric mobility. We can use all the cavities in the vehicle to transport the ionic liquid. As the liquid is neither flammable nor toxic, we believe we are absolutely on the right track with this medium." Nanoflowcell has been hard at work improving its powertrain design over the past 12 months. In addition to the larger liquid tanks, the design now incorporates a two-speed transmission and a new "buffer system" that can provide a brief 2,000 A output from the steady 50 A supply it receives from the flow cell. According to the company, that work results in the car performing even further off the charts than its predecessor, boasting a peak output (limited duration) of 1,075 hp (802 kW) and a maximum rated voltage of 735 V, up from 912 hp (680 kW) and 600 V, respectively. "To our knowledge, no one has ever before put a system delivering over 2,000 amperes on the road in a passenger car," La Vecchia says. "This is unique. We achieve this by combining our flow battery with the new buffer system. This system opens up vast potential for the future of electric mobility." Those lofty output numbers help draw attention to the Quant F, but the potential for Nanoflowcell's technology lies in clean, zero-emissions commuting. Toward that end, the company claims that the new Quant F offers a driving range of up to 500 miles (805 km), which is quite a significant boost from the 249- to 373-mile (400- to 600-km) range it was quoting last year. "I would expressly like to point out that we researchers are not interested here in pumping up PS/kW figures, but rather in realizing what is technically feasible," La Vecchia says. "For both technical and economic reasons, the rated voltage for normal operation of the Quant F will stand at approximately 400 V in future. This enables efficient and economical driving and means correspondingly greater ranges accompanied by outstanding performance with zero harmful emissions." Perhaps that's also why estimated top speed has plummeted from 236 mph (380 km/h) to 186 mph (300 km/h). Still, there's no hiding the fact that the Quant F is an all-out performance supercar concept, and its evolving equipment continues to reflect that fundamental fact. The new red show car gets a de-clutchable front axle that leaves the two rear motors to power the car in place of the usual four-motor AWD. "We endeavour to provide the driver with optimum acceleration and stability in every driving situation, especially at higher speeds," explains La Vecchia. "This is easier to achieve with rear-wheel drive than with permanent 4x4 drive." Other updated features on the new Quant F include a new carbon fiber monocoque with narrowed A pillar, an active, two-stage rear spoiler that increases downforce at speeds over 50 mph (80 km/h), and new Q-shaped "QUANTeYES" headlamps that give the car a set of eyes with pupils when turned on. We'll have trouble believing all Nanoflowcell's claims and specs until the car has been put on the road and thoroughly vetted by third parties. However, the Quant didn't disappear silently like we thought it might. Nanoflowcell did get the technology approved for use on German public roads and the company maintains that series production is its goal. "The exterior of the new QUANT F is already 100 percent in compliance with the requirements pertaining to series production homologation on a technical level," La Vecchia assures. "The interior is around 90 percent in compliance with homologation requirements. Homologation requirements currently still require to be met with regard to the font display, the airbags, the complex crash tests and formal tests and documentation. The crash tests are to be carried out in the USA and in Germany. Though I must say, the idea of putting such a fascinating car through a crash test really grates on me." Gizmag will be on the ground at next month's Geneva Motor Show, and we plan to take a much closer look at the Quant F and find out any and all additional details Nanoflowcell is willing to divulge. This should include our first look at the new interior, which has increased in spaciousness thanks to the new carbon monocoque. Nanoflowcell will have a larger Geneva presence than last year and has promised it will show one "further surprise" in addition to the Quant F and Quant E. In the meantime, you can compare the first photos of the new Quant F with last year's Quant E in our gallery. Source: Nanoflowcell

Geoengineering report: Scientists urge more research on climate intervention

Deep cuts in greenhouse gas emissions, while necessary, may not happen soon enough to stave off climate catastrophe. So, in addition, the world may need to resort to so-called geoengineering approaches that aim to deliberately control the planet's climate. That's according to a National Research Council committee that today released a pair of sweeping reports on climate intervention techniques. The University of Michigan's Joyce Penner, who is the Ralph J. Cicerone Distinguished University Professor of Atmospheric Science, served on the committee. Penner studies how clouds affect climate. The reports consider the two main ways humans could attempt to steer the Earth's system: We could try to take carbon dioxide out of the atmosphere. Or we could try to reflect more sunlight back into space. The committee examined the socioeconomic and environmental impacts as well as the costs and technological readiness of approaches in each category. The researchers said that certain CO2-removal tactics could have a place in a broader climate change response plan. But the sunlight reflecting technologies, on the other hand, are too risky at this point. They underscored how important it is for humans to limit the levels of CO2 they put into the atmosphere in the first place, and they called for more research into all climate intervention approaches. "I, for one, am concerned with the continuing rise in CO2 concentrations without clear efforts to reduce emissions," Penner said. "The widespread impacts from these increases are readily apparent, and the cost of climate change impacts is likely to be high. "We may need to employ some of these climate interventions techniques to avoid a catastrophe such as the loss of the Antarctic ice sheets, or even to remain below levels of climate change that are considered dangerous in the political arena." Techniques to remove CO2 include restoring forests and adopting low-till farming -- both of which trap carbon in plants and soils. Oceans could be seeded with iron to promote growth of CO2-consuming organisms. And carbon could be be sucked directly out of the air and injected underground. Methods to reflect sunlight include pumping sulfuric compounds into the stratosphere to, in essence, simulate a volcanic eruption; and spraying sea water mist or other finer-than-usual particles over the ocean. Smaller particles lead to brighter clouds, Penner said. While the committee said that some of the CO2 removal strategies including "carbon capture and sequestration" have potential to be part of a viable plan to curb climate change, it noted that only prototype sequestration systems exist today. Much development would have to occur before it could be ready for broad use. The scientists caution against dumping iron in the oceans, as the technical and environmental risks currently outweigh the benefits. Similarly, they warned against sunlight-reflecting approaches, also known as "albedo modification." These efforts might be able to reduce the Earth's temperature in just a few years, and they're relatively cheap when compared to transitioning to a carbon-free economy. But they'd have to be kept up indefinitely and could have numerous negative secondary effects on ozone, weather and human health. Even in its opposition to sunlight reflecting tactics, the committee still recommended more research into them, as it urged more study of all climate intervention possibilities. Penner was struck by this call to action. "U.S. agencies may have been reluctant to fund this area because of the sense of what we call 'moral hazard' -- that if you start down the road of doing this research you may end up relying on this or condoning this as a way of saving the planet from the cost of decreasing CO2 emissions," Penner said. "But we've stated that decreasing emissions must go hand in hand with any climate intervention efforts." Penner says the recommendation is a sign of the climate problem's urgency. "We need to develop the knowledge base to allow informed decisions before these dangerous effects are upon us," she said. The study was sponsored by the National Academy of Sciences, U.S. intelligence community, National Aeronautics and Space Administration, National Oceanic and Atmospheric Administration, and U.S. Department of Energy. The National Academy of Sciences is a private, independent nonprofit institution that provides science, technology and health policy advice under a congressional charter granted to NAS in 1863. The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering.

Want to save the planet? Neighbors better allies than family

Socializing with neighbors leads to more planet-friendly behaviors than visits with family or friends, say University of Vermont researchers. Know your neighbor, save the planet. That's the key finding of a study that says visits with neighbors lead to more planet-friendly behaviors than spending time with friends or family. The study, published by Environment and Behavior journal, finds that people who socialize with neighbors are more likely to 'keep up with the Jones' on green behaviors, including water and energy conservation, buying organic fruits and vegetables, and driving less. "These findings suggest that our neighbors play a unique and key role in getting people to act on climate change," says study author Thomas Macias of the University of Vermont (UVM). "Surprisingly, these green outcomes were higher with neighbors than family relatives or close friends." Researchers blame the differences, in part, on the overwhelming similarity of loved ones due to shared cultural and socio-economic upbringings. "This similarity provides emotional benefits, but limits our exposure to important new ideas," says Macias, a professor in UVM's Sociology Department. In contrast, neighbors are relatively diverse enough to expose us to greater amounts of new information, such as environmental issues and practices. And shared geography means neighborhood discussions will naturally gravitate towards sustainability matters. To identify predictors of green behavior, researchers used the 2010 U.S. General Survey, the largest and most recent national collection of Americans' environmental attitudes and behavior. They compared green outcomes with three variables: personal relationships, generalized trust and participation in community organizations. "Neighbors can be important role models," Macias says. "Backyard conversations, sidewalk exchanges and neighborly visits may be some of the best ways to learn about environmentally friendly practices." Bottom-line: Be kind to your neighbors: they may hold the secret to greater action on climate change, researchers say. The title of the study is Know Your Neighbors, Save the Planet: Social Capital and the Widening Wedge of Pro-Environmental Outcomes. The study was co-authored by Thomas Macias and UVM graduate student Kristin Williams. Key findings: • Socializing with neighbors is positively linked to a set of environmental behaviors, namely, buying chemical-free fruits and vegetables, using less water, consuming less household energy, and driving less • Generalized trust in others is positively linked to a willingness to make personal sacrifices for the environment through green taxes, higher prices and standard of living reductions • Hours watching TV was negatively associated with a willingness to make standard of living reductions for the benefit of the environment. • Religious attendance significantly was positively linked to the likelihood that respondents would be willing pay higher taxes and higher prices for the benefit of the natural environment The findings suggest amenities that foster community dialogue -- from online forums to common social areas -- could be a cost-effective way to promote increased adoption of green behaviors. The standard measures of environmental concern, including self-reported knowledge of environmental issues, were the most consistent predictors of green behavior. However, the study identifies several statistically important new predicators of environmental behaviors. The findings advance two fields: environmental sociology -- which explores the relationship between social interactions and human environmental impacts -- and social capital, which highlights the importance of individual and community connections in education, housing, jobs and personal health. While family visits ('bonding ties') tend to focus on the emotional needs of family members, neighborly exchanges ('bridging ties') tend to focus on community concerns, researchers say. The study will appear in a forthcoming print edition of Environment and Behavior and garnered advance publication online in 2014.

Elementary teachers' depression symptoms related to students' learning

February 11, 2015 Society for Research in Child Development A new study has found that teachers who report having more symptoms of depression had classrooms that were of lesser quality, and that students in these classrooms had fewer performance gains. Researchers looked at 27 teachers and their 523 third-grade students in a Florida school district. Teachers reported the frequency of their symptoms of clinical depression, and students' basic reading and math skills were assessed throughout the year. Teachers experience some of the highest levels of job-related stress, and such stress may leave them more vulnerable to depression. How do elementary school teachers' symptoms of depression affect the quality of the classroom environment and students' learning? A new study has found that teachers who reported more symptoms of depression than their fellow teachers had classrooms that were of lesser quality across many areas, and students in these classrooms had lower performance gains, particularly in math. "Teaching is one of the most stressful occupations," notes Leigh McLean, doctoral student in the Department of Psychology, and Carol Connor, professor of psychology, at Arizona State University, who conducted the study, beginning when they were at Florida State University. "One of the troubling consequences of occupational stress is that it can contribute to elevated rates of symptoms of depression. Our study reveals some of the negative implications of higher rates of teachers' symptoms of depression for students." The study appears in the journal Child Development. The researchers looked at 27 teachers and their 523 third-grade students (primarily White and from a range of socioeconomic backgrounds) in a Florida school district. Teachers reported the frequency of their symptoms of clinical depression, and students' basic reading and math skills were assessed throughout the year. Using classroom video recordings, trained observers assessed the quality of the classroom environment. The students who were the most vulnerable to the negative effects of their teachers' depression were those who were already struggling in math, suggesting that the children who needed to improve the most were less likely to be able to do so when they were in classrooms with more depressed teachers. Students with weaker math achievement made greater gains when they were in higher-quality classrooms with less depressed teachers. Teaching is consistently identified as one of the most stressful occupations in the United States, but almost no mental health support systems exist in schools to help teachers cope with this chronic stress. Research on depression and teaching is sparse, but one study of early education teachers found that almost 25 percent had diagnosed depression, compared with about 18 percent of nonteachers. Although some pioneering studies have looked at the effectiveness of mental health interventions on teachers' classroom performance--and suggest that such programs have strong potential for positive change--most current models of professional development don't address mental health. "Our study is one of the first to reveal that the constellation of symptoms that point to risks for depression hurt not only the teachers who experience these symptoms, but also the development of the teachers' students--especially students who are struggling academically," McLean and Connor note. "The study highlights the need for nationwide mental health support systems for educators, not only for teachers' benefit, but for the benefit of students." Specifically, the study's authors suggest that schools engage mental health professionals to help teachers deal with depression. Professional development programs that help teachers learn how to handle adverse and stressful situations in the classroom as they're teaching would be beneficial, as would providing comprehensive health insurance that covers mental health support, they say. Story Source: The above story is based on materials provided by Society for Research in Child Development. Note: Materials may be edited for content and length. Journal Reference: Leigh McLean and Carol McDonald Connor. Depressive Symptoms in Third-Grade Teachers: Relations to Classroom Quality and Student Achievement. Child Development, 11 FEB 2015 DOI: 10.1111/cdev.12344

NASA releases details of Titan submarine concept

The Titan submarine would use a large dorsal fin as an antenna (Image: NASA) Now that NASA has got the hang of planetary rovers, the space agency is looking at sending submarines into space around the year 2040. At the recent 2015 NASA Institute for Advanced Concepts (NIAC) Symposium in Cocoa Beach, Florida, NASA scientists and engineers presented a study of the Titan Submarine Phase I Conceptual Design, which outlines a possible mission to Saturn's largest moon, Titan, where the unmanned submersible would explore the seas of liquid hydrocarbons at the Titanian poles. If you had to choose the odd man out of all the moons of the Solar System, Titan would be it. Larger than the planet Mercury, it's the only moon with a proper atmosphere. In this case, one composed largely of nitrogen and methane at a pressure one and half times that of Earth's, which is remarkable when you consider that the gravity is only 0.14 g. It is, however, unpleasantly cold at a nippy minus 290 °F (minus 179 °C). As a result of the Voyager and Cassini probe flybys and the Huygens probe landing, it's been established that there are three large polar seas on Titan consisting of methane and ethane in a composition similar to that of liquified natural gas. The largest of these is Kraken Mare, which was discovered by the Cassini probe n 2007. It lies in the Titanian arctic between 60 and 80 degrees north latitude, covers 400,000 sq km (154,000 sq miles), and may be 160 m (525 ft) deep, though some estimates place it beyond 300 m (1,000 ft). It even has tides due to the pull of Saturn, a complex shoreline, and evaporite deposits, so it's of particular interest to scientists. Unfortunately, as anyone who has peered over the side of a boat can tell you, there's only so much that can be learned by looking at the surface, so NASA is considering what kind of a submarine would be able to explore the depths of Kraken Mare. NASA's conceptual Titan submarine is based on experience gained from the building and operations of drone submersibles on Earth. Weighing in at about one tonne (2,200 lb), it uses conventional electric propulsion modified for use on Titan for a 90-day mission covering 2,000 km (1,240 miles) of Kraken Mare. Because of its elongated shape, the sub would need to be delivered to the surface of Titan using a winged spacecraft similar to US Air Force X-37 lifting body, which could survive a hypersonic entry into Titan's atmosphere, ditch on the surface of Kraken Mare, and then sink away, leaving the submarine floating on the surface. After orientation and testing, the sub would then begin its mission. Because of the great distance from Earth, the submarine would operate with a very high level of autonomy. At its heart, the submarine would use a 1 kW radiothermal Stirling generator. This would not only provide power to propel the craft, but it would also keep the electronics from freezing. Unfortunately, Titan is so cold that it's almost a cryogenic environment, so the waste heat from the generator would cause the liquids around it to boil and this would need be taken into account when designing the sub to minimize interference. However, NASA estimates that the boat could do about one meter per second (3.6 km/h, 2.2 mph). For economy and simplicity, the conceptual submarine would not use an orbiter as a relay because an orbiter would need to be nuclear powered and include a propulsion system, which would greatly increase the cost and complexity of the mission. Due to the large amount of data that needs to sent to Earth, the submarine needs a large dorsal fin that includes a planar phased-array antenna. While operating, the submarine would surface for 16 hours per day for Earth communications during which it would study its surroundings using a mast camera. This is a bonus because the high latitudes mean any break in the Titanian clouds would be rewarded with spectacular views of Saturn on the horizon. Like an earthbound submarine, the Titan sub would use ballast tanks, but their design is still open to question because methane and ethane are not water and Titan is very different from Earth. The liquid density of different ratios of methane to ethane, for example, is very variable compared to that of fresh versus salt water, so something as basic as the size of the tanks has yet to be sorted out. Titan's gravity is low, but if Kraken Mare is as deep as some theories indicate, and taking into account the composition and temperature of the Titanian atmosphere, it could also cause trouble because at great depths the nitrogen in the ballast tanks could condense into a liquid, which could result in a sudden loss of buoyancy. For this reason, the tanks would need to use a piston to allow in and expel liquid rather than relying on air pressure as in a conventional submarine. NASA doesn't say much about the objectives of the Titan submarine, but it would probably be a full itinerary. This would likely include the study of the structure and composition of Kraken Mare in terms of both its liquid and its sediment. Also, since Titan has an overabundance of organic chemicals, the submarine would be tasked with looking for traces of prebiotic compounds that could give clues as to how life began on Earth. The animation below shows the conceptual Titan submarine in action. Source: NASA (PDF)

New electronic technique promises to double optical fiber communications reach

A new method developed by University College, London (UCL) has managed to double the distance that signals can be sent along fiber optic cable (Photo: UCL) A new method of processing signals via fiber optic cables could vastly increase the distance at which error-free data is transmitted via submarine cables without additional signal amplification. As the technique is capable of correcting corrupted or distorted data being transmitted, it may also assist in increasing the capacity of all optical fiber communications. With demand for internet connectivity running at an all time high – and only increasing – the fiber optic cables over which much of the data flows draw ever-closer to reaching capacity. Short of laying more cables, growing demand is being increasingly met by boosting the number of available frequency channels on which the data, in the form of encoded light signals, is transmitted. This is often achieved using a variety of compression and error-correction techniques, as well as employing methods designed to overcome nonlinearity in long lengths of optical fiber. Unfortunately, given that many of these techniques are reaching the limit of their capaabilities to transmit and receive light without adjacent light signal overlap and subsequent interference, data is often received with distortion errors. To address this problem, researchers from University College London (UCL) have created a way of avoiding such interference by using a set of frequencies that are coded using amplitude, phase, and frequency to create an exceptionally large-capacity, high-quality optical signal. In detail, the research team used a laser to generate the optical carrier and passed this through a comb generator to form seven equidistantly-spaced, frequency locked signals in the form of Quadrature Amplitude Modulation (QAM) – specifically a 16QAM super-channel. This super-channel signal was then introduced into one end of a fiber optic cable and captured at the other end with a high-speed super-receiver. Employing a range of new signal processing techniques specifically developed by the researchers, reception of all the channels was received intact and without error. "By eliminating the interactions between the optical channels, we are able to double the distance signals can be transmitted error-free, from 3,190 km (1,982 mi) to 5,890 km (3,660 mi), which is the largest increase ever reported for this system architecture," said Dr Robert Maher of UCL's Electronic & Electrical Engineering department. "The challenge is to devise a technique to simultaneously capture a group of optical channels, known as a super-channel, with a single receiver. This allows us to undo the distortion by sending the data channels back on a virtual digital journey at the same time." Using the full 70 GHz bandwidth available to the optical super-channel, the maximum reach the system was able to achieve was an experimentally-confirmed 5,890 km transmission distance equivalent. This is the largest distance gain ever reported that incorporates digital back-propagation. Following on from the successful testing of the new method, the researchers now intend to conduct research on incorporating these techniques in denser super-channels commonly used in digital cable TV, cable modems, and Ethernet connections. “We’re excited to report such an important finding that will improve fiber optic communications," said Professor Polina Bayvel, also of UCL Electronic & Electrical Engineering. "Our method greatly improves the efficiency of transmission of data – almost doubling the transmission distances that can be achieved, with the potential to make significant savings over current state-of-the art commercial systems. One of the biggest global challenges we face is how to maintain communications with demand for the internet booming – overcoming the capacity limits of optical fiber cables is a large part of solving that problem.” The results of the research have been published in the journal Scientific Reports. Source: UCL

29 Fascinating Photos You’ve Probably Never Seen Before

01/12/2015 1 95103 The lava lake of the continuously active volcano Erta Ale, Ethiopia Where the Great Wall of China ends A geyser right before eruption Bavarian town of Nordlingen built in a 14 million year old meteor impact crater A huge dust storm that hit Western Australia in early 2013 A rare 360 degree rainbow captured from an airplane Climbers going up Mount Everest in May 2013 Daytona Beach 1957 An aerial view of a scrap tire dump Bagger 288, the largest land vehicle in the world A cross-section of an undersea cable Inside one of Google’s data centers Einstein’s desk hours after his death Michelangelo illustrated his grocery lists so that his illiterate servants would know what to buy him. The inside of a FedEx Boeing 757 without any cargo Overcrowded prison in El Salvador Hitler’s office Enormous statue of Genghis Khan in Mongolia What pugs looked like before selective breeding Octopus eggs George Washington’s teeth A watch belonging to Akito Kawagoe which stopped at 8:15, the exact time of the Hiroshima bombing in 1945 A microscopic image of a human tongue Five pounds of fat compared to five pounds of muscle Cancer cells under an electron microscope X-rays before and after treatment for scoliosis The clearest photo of Mercury ever taken Mars in true color from the Curiosity Rover The northern lights from space