Potential Cure Discovered for Degenerative Vision Diseases Leading to Terminal Blindness

 Neurobiologists funded by the Office of Naval Research (ONR) have discovered a potential cure for degenerative vision diseases leading to terminal blindness. The solution, however, may be rooted in an unconventional therapeutic approach.


Scientists at the Friedrich Miescher Institute for Biomedical Research in Basel, Switzerland, are manipulating the proteins that cause blindness in mice. The scientists have successfully restored vision in the light-sensing cells of the retina.

Dr. Thomas McKenna, program officer for ONR's Neural Computation Program, said this research has significant future implications.

"In the course of their study, these researchers discovered an approach to restore vision in blind mice with congenital macular degeneration," McKenna said. "This technology shows great promise for the partial restoration of vision for blind patients."

This initiative, supported by ONR Global's Naval International Cooperative Opportunities in Science and Technology Program (NICOP), studies retinitis pigmentosa, the incurable genetic eye disease, which causes more than 2 million worldwide cases of tunnel vision and night blindness. If left untreated, the disease can lead to complete blindness as the color-sensing cells in the retina slowly degenerate.

Dr. Clay Stewart, technical director, ONR Global, explained the importance of the NICOP program for providing a platform for innovative international basic research that could ultimately have a profound impact on naval activities.

McKenna, a recipient of the 2009 Delores M. Etter Top Scientists and Engineers of the Year award, said additional studies are needed before making the treatment available to visually challenged populations. Next, the team plans to explore the duration of therapeutic effects and whether the gene therapy could have applications for other eye diseases.

ONR's research is part of a global effort to combat visual diseases. The American Foundation for the Blind, a national nonprofit organization, reports that more than 25 million U.S. adults have some form vision loss. According to the Foundation Fighting Blindness, about 100,000 Americans suffer from retinitis pigmentosa.

another kind of the solar power

Call it the anti-sunscreen. That's more or less the description of what many solar energy researchers would like to find -- light-catching substances that could be added to photovoltaic materials in order to convert more of the sun's energy into carbon-free electricity.


Research reported in the journal Applied Physics Letters, published by the American Institute of Physics (AIP), describes how solar power could potentially be harvested by using oxide materials that contain the element selenium. A team at the Lawrence Berkeley National Laboratory in Berkeley, California, embedded selenium in zinc oxide, a relatively inexpensive material that could be promising for solar power conversion if it could make more efficient use of the sun's energy. The team found that even a relatively small amount of selenium, just 9 percent of the mostly zinc-oxide base, dramatically boosted the material's efficiency in absorbing light.

"Researchers are exploring ways to make solar cells both less expensive and more efficient; this result potentially addresses both of those needs," says author Marie Mayer, a fourth-year University of California, Berkeley doctoral student based out of LBNL's Solar Materials Energy Research Group, which is working on novel materials for sustainable clean-energy sources.


Mayer says that photoelectrochemical water splitting, using energy from the sun to cleave water into hydrogen and oxygen gases, could potentially be the most exciting future application for her work. Harnessing this reaction is key to the eventual production of zero-emission hydrogen powered vehicles, which hypothetically will run only on water and sunlight. Like most researchers, Mayer isn't predicting hydrogen cars on the roads in any meaningful numbers soon. Still, the great thing about solar power, she says, is that "if you can dream it, someone is trying to research it."

issue on climate change

The way that humanity reacts to climate change may do more damage to many areas of the planet than climate change itself unless we plan properly, an important new study published in Conservation Letters by Conservation International's Will Turner and a group of other leading scientists has concluded.


The paper Climate change: helping nature survive the human response, looks at efforts to both reduce emissions of greenhouse gases and potential action that could be taken by people to adapt to a changed climate and assesses the potential impact that these could have on global ecosystems.

In particular it notes that one fifth of the world's remaining tropical forests lie within 50km of human populations that could be inundated if sea levels rise by 1m. These forests would make attractive sources of fuel-wood, building materials, food and other key resources and would be likely to attract a population forced to migrate by rising sea levels. About half of all Alliance for Zero Extinction sites - which contain the last surviving members of certain species - are also in these zones.

Dr Turner said: "There are numerous studies looking at the impacts of climate change on biodiversity, but very little time has been taken to consider what our responses to climate change might do to the planet."

The paper notes that efforts to reduce greenhouse gas emissions by constructing dams for hydropower generation can cause substantial damage to key freshwater ecosystems as well as to the flora and fauna in the flooded valleys. It also notes that the generally bogus concept that biofuels reduce carbon emissions is still being used as a justification for the felling of large swathes of biodiverse tropical forests.

The report also reviews studies examining the complex series of outcomes in historical examples of climate change and environmental degradation, and humanity's efforts to adapt to changing circumstances. Migration caused in part by climatic instability in Burkina Faso in the late 20th century, for example, led to a 13 per cent decline in forest cover as areas were cleared for agriculture, and a decline in fish supplies in Ghana may have led to a significant increase in bushmeat hunting.

Dr Turner added: "If we don't take a look at the whole picture, but instead choose to look only at small parts of it we stand to make poor decisions about how to respond that could do more damage than climate change itself to the planet's biodiversity and the ecosystem services that help to keep us all alive.

"While the Tsunami in 2004 was not a climate event, many of the responses that it stimulated are comparable with how people will react to extreme weather events - and the damage that the response to the Tsunami did to many of Aceh province's important ecosystems as a result of extraction of timber and other building materials, and poor choices of locations for building , should be a lesson to us all."

Although the challenge of sustaining biodiversity in the face of climate change seems daunting, the paper notes that we must - and can - rise to the challenge.

Turner adds: "Climate change mitigation and adaptation are essential. We have to ensure that these responses do not compromise the biodiversity and ecosystem services upon which societies ultimately depend. We have to reduce emissions, we have to ensure the stability of food supplies jeopardized by climate change, we have to help people survive severe weather events - but we must plan these things so that we don't destroy life-sustaining forests, wetlands, and oceans in the process.'

The paper concludes that there are many ways of ensuring that the human response to climate change delivers the best possible outcomes for both society and the environments, and notes that in particular, maintaining and restoring natural habitats are among the cheapest, safest, and easiest solutions at our disposal to reduce greenhouse-gas emissions and help people adapt to unavoidable changes.

Dr Turner said: "Providing a positive environmental outcome is often the best way to ensure the best outcome for people. If we are sensible, we can help people and nature together cope with climate change, if we are not it will cause suffering for people and serious problems for the environment."

FACTS ON TOYOTA COMPANY

Toyota Motor said Friday that its hybrid vehicle sales in Japan had topped the one million mark and worldwide it had sold 2.68 million of the vehicles by the end of July.



Toyota Motor said Friday that its hybrid vehicle sales in Japan had topped the one million mark and worldwide it had sold 2.68 million of the vehicles by the end of July.

Toyota, the front-runner in hybrid cars that use two power sources -- a gasoline engine and another source such as an electric motor -- launched the Prius, the world's first mass-produced hybrid car, in 1997.


The world's biggest automaker later expanded use of its hybrid system to mini-vans, SUVs and rear-wheel-drive sedans.


Currently, nine Toyota-produced hybrid passenger vehicle models and three hybrid commercial vehicle models are sold in Japan and a total of eight passenger hybrid models overseas.


Sales of hybrids have been brisk in recent years because of high gasoline prices and increasing public awareness of global warming.


Last year, Toyota recalled 437,000 Prius and other hybrid vehicles to repair a flaw in the braking system, as part of around 10 million recalls worldwide that have tarnished its previously stellar reputation for quality.


However the Prius has retained the top spot in sales in Japan for the past year, according to the Japan Automobile Dealers Association.

artificial bee eye and lens

Despite their tiny brains, bees have remarkable navigation capabilities based on their vision. Now scientists have recreated a light-weight imaging system mimicking a honeybee's field of view, which could change the way we build mobile robots and small flying vehicles.

                                                          

                                           

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New research published Aug. 6 in IOP Publishing's Bioinspiration & Biomimetics, describes how the researchers from the Center of Excellence 'Cognitive Interaction Technology' at Bielefeld University, Germany, have built an artificial bee eye, complete with fully functional camera, to shed light on the insects' complex sensing, processing and navigational skills.

Consisting of a light-weight mirror-lens combination attached to a USB video camera, the artificial eye manages to achieve a field of vision comparable to that of a bee. In combining a curved reflective surface that is built into acrylic glass with lenses covering the frontal field, the bee eye camera has allowed the researchers to take unique images showing the world from an insect's viewpoint.



In the future, the researchers hope to include UV to fully reflect a bee's colour vision, which is important to honeybees for flower recognition and discrimination and also polarisation vision, which bees use for orientation. They also hope to incorporate models of the subsequent neural processing stages.

As the researchers write, "Despite the discussed limitations of our model of the spatial resolution of the honeybees compound eyes, we are confident that it is useful for many purposes, e.g. for the simulation of bee-like agents in virtual environments and, in combination with presented imaging system, for testing bee-inspired visual navigation strategies on mobile robots."

New Solar Energy Conversion Process Could Double Solar Efficiency of Solar Cells

A new process that simultaneously combines the light and heat of solar radiation to generate electricity could offer more than double the efficiency of existing solar cell technology, say the Stanford engineers who discovered it and proved that it works. The process, called "photon enhanced thermionic emission," or PETE, could reduce the costs of solar energy production enough for it to compete with oil as an energy source.



Stanford engineers have figured out how to simultaneously use the light and heat of the sun to generate electricity in a way that could make solar power production more than twice as efficient as existing methods and potentially cheap enough to compete with oil.




 


Unlike photovoltaic technology currently used in solar panels -- which becomes less efficient as the temperature rises -- the new process excels at higher temperatures.



Called "photon enhanced thermionic emission," or PETE, the process promises to surpass the efficiency of existing photovoltaic and thermal conversion technologies.



"This is really a conceptual breakthrough, a new energy conversion process, not just a new material or a slightly different tweak," said Nick Melosh, an assistant professor of materials science and engineering, who led the research group. "It is actually something fundamentally different about how you can harvest energy."



And the materials needed to build a device to make the process work are cheap and easily available, meaning the power that comes from it will be affordable.



Melosh is senior author of a paper describing the tests the researchers conducted. It was published this week in Nature Materials.



"Just demonstrating that the process worked was a big deal," Melosh said. "And we showed this physical mechanism does exist, it works as advertised."



Most photovoltaic cells, such as those used in rooftop solar panels, use the semiconducting material silicon to convert the energy from photons of light to electricity. But the cells can only use a portion of the light spectrum, with the rest just generating heat.



This heat from unused sunlight and inefficiencies in the cells themselves account for a loss of more than 50 percent of the initial solar energy reaching the cell.



If this wasted heat energy could somehow be harvested, solar cells could be much more efficient. The problem has been that high temperatures are necessary to power heat-based conversion systems, yet solar cell efficiency rapidly decreases at higher temperatures.



Until now, no one had come up with a way to wed thermal and solar cell conversion technologies.



Melosh's group figured out that by coating a piece of semiconducting material with a thin layer of the metal cesium, it made the material able to use both light and heat to generate electricity.



"What we've demonstrated is a new physical process that is not based on standard photovoltaic mechanisms, but can give you a photovoltaic-like response at very high temperatures," Melosh said. "In fact, it works better at higher temperatures. The higher the better."



While most silicon solar cells have been rendered inert by the time the temperature reaches 100 degrees Celsius, the PETE device doesn't hit peak efficiency until it is well over 200 degrees C.



Because PETE performs best at temperatures well in excess of what a rooftop solar panel would reach, the devices will work best in solar concentrators such as parabolic dishes, which can get as hot as 800 degrees C. Dishes are used in large solar farms similar to those proposed for the Mojave Desert in Southern California and usually include a thermal conversion mechanism as part of their design, which offers another opportunity for PETE to help generate electricity, as well as minimizing costs by meshing with existing technology.



"The light would come in and hit our PETE device first, where we would take advantage of both the incident light and the heat that it produces, and then we would dump the waste heat to their existing thermal conversion systems," Melosh said. "So the PETE process has two really big benefits in energy production over normal technology."



Photovoltaic systems never get hot enough for their waste heat to be useful in thermal energy conversion, but the high temperatures at which PETE performs are perfect for generating usable high temperature waste heat. Melosh calculates the PETE process can get to 50 percent efficiency or more under solar concentration, but if combined with a thermal conversion cycle, could reach 55 or even 60 percent -- almost triple the efficiency of existing systems.



The team would like to design the devices so they could be easily bolted on to existing systems, making conversion relatively inexpensive.



The researchers used a gallium nitride semiconductor in the "proof of concept" tests. The efficiency they achieved in their testing was well below what they have calculated PETE's potential efficiency to be, which they had anticipated. But they used gallium nitride because it was the only material that had shown indications of being able to withstand the high temperature range they were interested in and still have the PETE process occur.



With the right material -- most likely a semiconductor such as gallium arsenide, which is used in a host of common household electronics -- the actual efficiency of the process could reach up to the 50 or 60 percent the researchers have calculated. They are already exploring other materials that might work.



Another advantage of the PETE system is that by using it in solar concentrators, the amount of semiconductor material needed for a device is quite small.



"For each device, we are figuring something like a six-inch wafer of actual material is all that is needed," Melosh said. "So the material cost in this is not really an issue for us, unlike the way it is for large solar panels of silicon."



The cost of materials has been one of the limiting factors in the development of the solar power industry, so reducing the amount of investment capital needed to build a solar farm is a big advance.



"The PETE process could really give the feasibility of solar power a big boost," Melosh said. "Even if we don't achieve perfect efficiency, let's say we give a 10 percent boost to the efficiency of solar conversion, going from 20 percent efficiency to 30 percent, that is still a 50 percent increase overall."



And that is still a big enough increase that it could make solar energy competitive with oil.



The research was largely funded by the Global Climate and Energy Project at Stanford and the Stanford Institute for Materials Energy Systems, which is a joint venture of Stanford and SLAC National Accelerator Laboratory, with additional support from the Department of Energy and DARPA.


A small PETE device made with cesium-coated gallium nitride glows while being tested inside an ultra-high vacuum chamber. The tests proved that the process simultaneously converted light and heat energy into electrical current.
SEE THE PICTURE OF THE DEVICE BELOW:

Research Breakthrough on the Question of Life Expectancy

                                           simple fact on biology

  Why do we grow old and what can we do to stop it? This is the question asked by many, but it appears that we are now closer to an answer thanks to new research published by Monash University researcher Dr Damian Dowling.



According to the research published in the August edition of the journal, The American Naturalist, a small set of genes in mitochondria (a membrane-enclosed organelle found in most eukaryotic cells), passed only from mothers to offspring, plays a more dynamic role in predicting life expectancies than ever previously anticipated.



The research discovered that particular mitochondrial haplotypes were linked to the life expectancies of females in the beetle species Callosobruchus maculatus.



"What we found in these beetles that some combinations of mitochondrial and nuclear genomes confer long life in virgin females, but these are not the same combinations that result in long life in females that mate once, or in females that mate many times," Dr Dowling said.



"Clearly, the genetic determinants underlying life expectancies are complex.



"As we unravel this complexity, we draw closer to the day in which we might use the genetic information encoded in the mitochondria to assist in the development of therapies that slow the onset of ageing in humans," Dr Dowling said.



In animals, most of the genetic material that controls bodily functions is found inside the cell nucleus. This is the nuclear genome -- it is passed on from generation to generation through both mothers and fathers, and it encodes somewhere between 14 thousand and 40 thousand proteins.



However, a separate genome exists that is found only within the energy-producing factories of our cells -- the mitochondria. To put things in perspective, the mitochondrial genome is tiny, encoding just 13 proteins. Despite being so small, it can pack a punch when it comes to its ability to affect a range of fundamental biological processes.



Dr Dowling, a research fellow at Monash University's School of Biological Sciences led the research together with Goran Arnqvist of Uppsala University Sweden and their student, Tejashwari Meerupati, made the discovery.



"Our findings are part of a much broader research agenda in which we are elucidating the ways in which mitochondrial genomes have shaped our evolutionary past and present. What we are finding is that natural variation in this diminutive genome results in a huge range of effects on metabolism, mating behaviour and reproductive biology, including male fertility," Dr Dowling said.



"At the outset of our research program, we suspected that the evolutionary significance of the mitochondria had probably been underestimated by scientists that have come before us, but even we have been continually surprised by the magnitude and ubiquity of the effects that we have uncovered.



"We suspect that this genome still harbours many more secrets awaiting discovery," Dr Dowling said.