University of Wisconsin-Madison electrical engineers have created the fastest, most responsive flexible silicon phototransistor ever made.
night-vision goggles and smoke detectors to surveillance systems and satellites--that rely on electronic light sensors. Integrated into a digital camera lens, for example, it could reduce bulkiness and boost both the acquisition speed and quality of video or still photos.
Developed by UW-Madison collaborators Zhenqiang"Jack"Ma, professor of electrical and computer engineering and research scientist Jung-Hun Seo, the high-performance phototransistor far and away exceeds all previous flexible phototransistor parameters,
and 0s that create the digital image. While many phototransistors are fabricated on rigid surfaces and therefore are flat,
At that point, a reflective metal layer is on the bottom.""In this structure--unlike other photodetectors--light absorption in an ultrathin silicon layer can be much more efficient
The researchers also placed electrodes under the phototransistor's ultrathin silicon nanomembrane layer--and the metal layer and electrodes each act as reflectors
and improve light absorption without the need for an external amplifier.""There's a built-in capability to sense weak light,
whose work was supported by the U s. Air force.""It shows the capabilities of high-sensitivity photodetection and stable performance under bending conditions,
#Researchers build nanoscale autonomous walking machine from DNA Researchers at The University of Texas at Austin have developed a nanoscale machine made of DNA that can randomly walk in any direction across bumpy surfaces.
Future applications of such a DNA walker might include a cancer detector that could roam the human body searching for cancerous cells
and tagging them for medical imaging or drug targeting. The study by researchers Cheulhee Jung, Peter B. Allen and Andrew Ellington, published this week in the journal Nature Nanotechnology,
developed DNA machines that were able to walk, unprogrammed and in different directions, over a DNA-coated surface.
Previously, nanoparticle walkers were only able to walk on precise and programmed one-and two-dimensional paths.
"This is an important step forward in developing nanoscale nucleic acid machines that can autonomously act under a variety of conditions,
"said Ellington, professor in the Department of Molecular Biosciences and member of the UT Center for Systems and Synthetic biology."
"DNA NANOTECHNOLOGY is especially interesting because it explores the world of'matter computers, 'where computations (including walking) are carried out by physical objects, rather than by electronic or magnetic shuttles.
DNA walkers may eventually allow protective cells to walk the surface of organs, constantly computing whether a cancer is present."
"More immediate practical applications may include deploying the DNA walker in the body so that it can amplify signals from cancer cells to make them more easily identified
and targeted by doctors. There also may be implications for future delivery of nanoscale therapeutics. Although it may be a long march from diagnosing cancer to curing it,
"All breakthroughs begin with baby steps. Only in this case, they are the steps of a DNA walker,
"said co-author Jung. The walker is made from a single piece of DNA with two legs connected by a torso.
Like a human it moves by putting one leg forward, then lifting the other leg
The study demonstrated that as the nanoscale machine walked, it did not go over the same area twice e
University of Wisconsin-Madison engineers have created miniature lenses with vast range of vision. Their new approach created the first-ever flexible Fresnel zone plate microlenses with a wide field of view--a development that could allow everything from surgical scopes to security cameras to capture a broader perspective at a fraction of the size required by conventional lenses.
Led by Hongrui Jiang, professor of electrical and computer engineering at UW-Madison, the researchers designed lenses no larger than the head of a pin and embedded them within flexible plastic.
An array of the miniature lenses rolled into a cylinder can capture a panorama image covering a 170-degree field of view."
"We got the idea from compound eyes, "says Jiang, whose work was published in the Oct 30 issue of the journal Scientific Reports."
Black silicon consists of clusters of microscopic vertical pillars, or nanowires. Incoming light bouncing between individual silicon nanowires cannot escape the complex structure,
making the material darker than dark. Rather than laying down layers of black silicon on top of a clear backdrop,
and etched silicon nanowires in the areas between aluminum rings. Then they seeped a polymer between the silicon nanowire pillars.
After the plastic support solidified they etched away the silicon backing, leaving bull's-eye patterned black silicon embedded in supple plastic.
This approach gave their lenses unprecedented crisp focusing capabilities, as well as the flexibility that enables them to capture a large field of view.
Jiang and his team--including postdoctoral scholar Mohammad J. Moghimi, graduate student Jayer Fernandes and recent graduate Aditi Kanhere--are exploring ways to integrate the lenses into existing optical detectors and directly incorporate silicon electronic components into the lenses themselves s
#Minuscule, flexible compound lenses magnify large fields of view Drawing inspiration from an insect's multifaceted eye,
University of Wisconsin-Madison engineers have created miniature lenses with vast range of vision. Their new approach created the first-ever flexible Fresnel zone plate microlenses with a wide field of view--a development that could allow everything from surgical scopes to security cameras to capture a broader perspective at a fraction of the size required by conventional lenses.
Led by Hongrui Jiang, professor of electrical and computer engineering at UW-Madison, the researchers designed lenses no larger than the head of a pin and embedded them within flexible plastic.
An array of the miniature lenses rolled into a cylinder can capture a panorama image covering a 170-degree field of view."
"We got the idea from compound eyes, "says Jiang, whose work was published in the Oct 30 issue of the journal Scientific Reports."
Black silicon consists of clusters of microscopic vertical pillars, or nanowires. Incoming light bouncing between individual silicon nanowires cannot escape the complex structure,
making the material darker than dark. Rather than laying down layers of black silicon on top of a clear backdrop,
and etched silicon nanowires in the areas between aluminum rings. Then they seeped a polymer between the silicon nanowire pillars.
After the plastic support solidified they etched away the silicon backing, leaving bull's-eye patterned black silicon embedded in supple plastic.
This approach gave their lenses unprecedented crisp focusing capabilities, as well as the flexibility that enables them to capture a large field of view.
Jiang and his team--including postdoctoral scholar Mohammad J. Moghimi, graduate student Jayer Fernandes and recent graduate Aditi Kanhere--are exploring ways to integrate the lenses into existing optical detectors and directly incorporate silicon electronic components into the lenses themselves s
#'Magic'plant discovery could lead to growing food in space QUT scientists have discovered the gene that will open the door for space-based food production.
Professor Peter Waterhouse, a plant geneticist at QUT, discovered the gene in the ancient Australian native tobacco plant Nicotiana benthamiana, known as Pitjuri to indigenous Aboriginals tribes.
Professor Waterhouse made the discovery while tracing the history of the Pitjuri plant, which for decades has been used by geneticists as a model plant upon
which to test viruses and vaccines. Professor Waterhouse made the discovery while tracing the history of the Pitjuri plant
which for decades has been used by geneticists as a model plant upon which to test viruses and vaccines."
"This plant is the'laboratory rat'of the molecular plant world, "he said, "we think of it as a magical plant with amazing properties."
"We now know that in 1939 its seeds were sent by an Australian scientist to a scientist in America
and have been passed from lab to lab all over the world.""By sequencing its genome and looking through historical records we have been able to determine that the original plant came from the Granites area near the Western australia and Northern territory border,
close to where Wolf Creek was filmed.""We know, through using a molecular clock and fossil records,
that this particular plant has survived in its current form in the wild for around 750,000 years."
"Lead researcher Dr Julia Bally said determining the exact species had led researchers on a quest to find out how the plant managed to survive in the wild for such a long period of time."
"What we found may have a big impact on future plant biotechnology research, "Dr Bally said."
"We have discovered that it is the plant equivalent of the nude mouse used in medical research.""
'and has done that to focus its energies on being able to germinate and grow quickly, rapidly flower,
"Professor Waterhouse, a molecular geneticist with QUT's Centre for Tropical Crops and Biocommodities, said scientists could use this discovery to investigate other niche
or sterile growing environments where plants were protected from disease --and space was an intriguing option."
Professor Waterhouse said the team's findings also have implications for future genetic research back here On earth."
So just as nude mice can be really good models for cancer research, 'nude'versions of crop plants could also speed up agricultural research,
"he said. Professor Waterhouse said the fact that the N. benthamiana variety from central Australia had doubled its seed size also opened the door for investigations into how N. benthamiana could be used commercially as a biofactory,
as seeds were an excellent place in which to make antibodies for pharmaceutical use e
#Researchers develop deep-learning method to predict daily activities Researchers from the School of Interactive Computing
and the Institute for Robotics and Intelligent Machines developed a new method that teaches computers to"see
"and understand what humans do in a typical day. The technique gathered more than 40,000 pictures taken every 30 to 60 seconds, over a 6 month period,
Researchers taught the computer to categorize images across 19 activity classes. The test subject wearing the camera could review
"said Steven Hickson, a Ph d. candidate in Computer science and a lead researcher on the project."
"This work is about developing a better way to understand people's activities, and build systems that can recognize people's activities at a finely-grained level of detail,
co-author and graduate research assistant in the School of Interactive Computing.""Activity tracking devices like the Fitbit can tell how many steps you take per day,
This work is moving toward full activity intelligence. At a technical level, we are showing that it's becoming possible for computer vision techniques alone to be used for this."
"The group believes they have gathered the largest annotated dataset of first-person images to demonstrate that deep-learning can understand human behavior and the habits of a specific person.
Student Daniel Casto, a Ph d. candidate in Computer science and a lead researcher on the project, helped present the method earlier this month at UBICOMP 2015 in Osaka, Japan.
He says reaction from conference-goers was positive.""People liked that we had a method that combines time and images,
and Ear/Harvard Medical school and Boston University have prevented successfully the development of Parkinson's disease in a mouse using new techniques to deliver drugs across the naturally impenetrable blood-brain barrier.
Their findings, published in Neurosurgery, lend hope to patients around the world with neurological conditions that are difficult to treat due to a barrier mechanism that prevents approximately 98 percent of drugs from reaching the brain and central nervous system."
"We are developing a platform that may eventually be used to deliver a variety of drugs to the brain,
Eye and Ear/Harvard Medical school.""Although we are currently looking at neurodegenerative disease, there is potential for the technology to be expanded to psychiatric diseases, chronic pain,
seizure disorders and many other conditions affecting the brain and nervous system down the road.""Using nasal mucosal grafting,
researchers delivered glial derived neurotrophic factor (GDNF), a known therapeutic protein for treating Parkinson's disease, to the brains of mice.
They showed through behavioral and histological data capture that their delivery method was equivalent to direct injection of GDNF-the current gold standard for delivering this drug in Parkinson's disease despite its traumatic nature and high complication rates-in diffusing drugs to the brain.
The researchers chose to test their delivery method with GDNF because the therapy has been shown to delay and even reverse disease progression of Parkinson's disease.
Nasal mucosal grafting is a technique regularly used in the ENT field to reconstruct the barrier around the brain after surgery to the skull base.
ENT surgeons commonly use endoscopic approaches to remove brain tumors through the nose by making a window through the blood-brain barrier to access the brain.
Once they have finished the treatment, they use adjacent nasal lining to rebuild the hole in a permanent and safe way.
with the nasal lining protecting the brain from infection just as the blood brain barrier has done. Dr. Bleier saw an opportunity to apply these techniques to the widespread clinical dilemma of delivering drugs across the barrier to the brain and central nervous system.
surgeons may create a"screen door"to allow for drug delivery to the brain and central nervous system. The technique has the potential to benefit a large population of patients with neurodegenerative disorders,
where there remains a specific unmet need for blood-brain penetrating therapeutic delivery strategies.""We see this expanding beyond Parkinson's disease,
as there are multiple diseases of the brain that do not have good therapeutic options, "Dr. Bleier said."
"It is a platform that opens doors for new discovery and could enable drug development for an underserved population."#
"##The study was supported by a grant from the Michael j fox Foundation for Parkinson's Research and represents a collaborative effort between Mass.
Eye and Ear and Dr. Xue Han of the Biomedical engineering Department at Boston University. Other authors include Richie E. Kohman, Kevin Guerra, Angela Nocera, Shrestha Ramanlal, Armine H. Kocharyan and William T. Curry.
Eye and Ear clinicians and scientists are driven by a mission to find cures for blindness, deafness and diseases of the head and neck.
developing new treatments and cures through discovery and innovation. Mass. Eye and Ear is a Harvard Medical school teaching hospital and trains future medical leaders in ophthalmology and otolaryngology, through residency as well as clinical and research fellowships.
Internationally acclaimed since its founding in 1824, Mass. Eye and Ear employs full-time, board-certified physicians who offer high-quality
U s. News & World Report's"Best Hospitals Survey"has ranked consistently the Mass. Eye and Ear Departments of Otolaryngology and Ophthalmology as top in the nation n
#Breakthrough to the development of energy saving devices for the next generation Wide-gap semiconductors such as gallium nitride (Gan) are used widely for optical devices such as blue LED
and are anticipated also as materials for next-generation energy saving power devices and solar cells. However, the quality of Gan crystals does not come up to that of conventional semiconductor materials such as silicon (Si)
and this prevents Gan from being used for power devices. For that reason, the establishment of technology for producing high-quality crystals with fewer defects
and rearrangement is expected, and the development of a new evaluation technology is crucial. A group of researchers led by Iwao Kawayama
an associate professor of the Institute of Laser Engineering at Osaka University, in cooperation with Screen Holdings Co.,Ltd.
succeeded in visualizing changes in defect density on the surface of Gan through the laser terahertz emission microscope (LTEM)
This group's discovery shows that LTEM is useful as a new method for evaluating the quality of wide-gap semiconductors
and it is expected also that LTEM will bring a breakthrough in the development of next-generation optical devices, super high frequency devices,
and energy devices. The group examined the intensity distribution of THZ generated by radiating ultraviolet femtosecond laser pulses on the surface of Gan crystal through LTEM.
As a result it was found that there were regions with high intensity of THZ emission and ones with low intensity of THZ emission.
Furthermore, from results measurement through modification of excited lasers, it was confirmed that THZ emission needs excitation light with larger energy than the band gap energy y
#Carnegie mellon researchers hack off-the-shelf 3-D printer towards rebuilding the heart As of this month, over 4,
000 Americans are on the waiting list to receive a heart transplant. With failing hearts, these patients have no other options;
Fortunately, recent work by a group at Carnegie mellon could one day lead to a world in
which transplants are no longer necessary to repair damaged organs.""We've been able to take MRI images of coronary arteries and 3-D images of embryonic hearts and 3-D bioprint them with unprecedented resolution and quality out of very soft materials like collagens,
alginates and fibrins,"said Adam Feinberg, an associate professor of Materials science and engineering and Biomedical engineering at Carnegie mellon University.
Feinberg leads the Regenerative Biomaterials and Therapeutics Group, and the group's study was published in the October 23 issue of the journal Science Advances.
"As excellently demonstrated by Professor Feinberg's work in bioprinting, our CMU researchers continue to develop novel solutions like this for problems that can have a transformational effect on society,
"said Jim Garrett, Dean of Carnegie mellon's College of Engineering.""We should expect to see 3-D bioprinting continue to grow as an important tool for a large number of medical applications."
"Traditional 3-D printers build hard objects typically made of plastic or metal, and they work by depositing material onto a surface layer-by-layer to create the 3-D object.
Printing each layer requires sturdy support from the layers below, so printing with soft materials like gels has been limited."
"3-D printing of various materials has been a common trend in tissue engineering in the last decade,
but until now, no one had developed a method for assembling common tissue engineering gels like collagen or fibrin,"said TJ Hinton,
a graduate student in biomedical engineering at Carnegie mellon and lead author of the study.""The challenge with soft materials--think about something like Jello that we eat--is that they collapse under their own weight
when 3-D printed in air, "explained Feinberg.""So we developed a method of printing these soft materials inside a support bath material.
which does not damage the delicate biological molecules or living cells that were bioprinted. As a next step, the group is working towards incorporating real heart cells into these 3-D printed tissue structures,
providing a scaffold to help form contractile muscle. Bioprinting is a growing field, but to date, most 3-D bioprinters have cost over $100,
000 and/or require specialized expertise to operate, limiting wider-spread adoption. Feinberg's group,
however, has been able to implement their technique on a range of consumer-level 3-D printers,
which cost less than $1, 000 by utilizing open-source hardware and software.""Not only is the cost low,
but by using open-source software, we have access to fine-tune the print parameters, optimize what we're doing
and maximize the quality of what we're printing, "Feinberg said.""It has enabled really us to accelerate development of new materials
and innovate in this space. And we are also contributing back by releasing our 3-D printer designs under an open-source license
#Physicists mimic quantum entanglement with laser pointer to double data speeds In a classic eureka moment,
a team of physicists led by The City College of New york and including Herriot-Watt University
and Corning Incorporated is showing how beams from ordinary laser pointers mimic quantum entanglement with the potential of doubling the data speed of laser communication.
Quantum entanglement is a phrase more likely to be heard on popular sci-fi television shows such as"Fringe"and"Doctor Who."
"Described by Albert Einstein as"spooky action at a distance, "when two quantum things are entangled,
if one is touched'the other will'feel it, 'even if separated by a great distance.""At the heart of quantum entanglement is entangled'nonseparability'-two things are described by an unfactorizable equation,
"said City College Phd student Giovanni Milione.""Interestingly, a conventional laser beam (a laser pointer)' s shape
"In principal, this could be used to double the data speed of laser communication, "said CCNY Distinguished Professor of Phyiscs Robert Alfano.""
""While there's no'spooky action at a distance, 'it's amazing that quantum entanglement aspects can be mimicked by something that simple
#Colorado river is contaminated after mine cleanup goes wrong Workers from an environmental protection team have caused accidentally an environmental disaster releasing millions of litres of toxic wastewater into a river in Colorado.
The spill has turned the Animas River into a mustard-coloured pollution zone with the contaminated leak said to contain heavy metals like arsenic, mercury and lead,
It started when workers from the US Environmental protection agency were cleaning up an abandoned mine and inadvertently unleashed a flow of the orange-tinged slurry.
There are reports of residents weeping as the once crystal clear Animas River was closed down in an emergency measure The long-term environmental effects of the spill remain unclear e
#Chinese claim world's first 3d blood vessel bioprinter One step further towards organ regeneration. A Chinese biotechnological company claims to be have created the world first 3d blood vessel bioprinter,
which could pave the way, in theory, to producing personalised, functional organs. One of the major stumbling blocks in tissue engineering is supplying artificial tissue with nutrients,
this bioprinter can finish a 10-centimeter blood vessel within two minutes. he core of the printer is the Biobrick,
Given certain environments and certain conditions, stem cells can, according to our needs, differentiate into the cells we need,
the 3d bioprinter creates layered cell structures that can be cultivated to form tissues with physiological functions. he achievement here in producing a 3d blood vessel bioprinter is not just that we can print a blood vessel,
and other medical devices have been pumped out of 3d printers, but never before has the technology proven so integral to the production of a pill.
This form of the drug, called Spritam, wouldn work with conventional production methods. Traditional 3d printing with plastics is done by heating a polymer,
then applying it layer by layer to build an object. The 3d printing technology (called Zipdose) developed by Aprecia Pharmaceuticals isn much different.
Doctors would also have the option of adjusting doses as they like, rather than relying on drug makers to provide a pill in one dose or another.
I point out this seems like a great way to tweak a non-patented drug with proprietary technology and sell it for a higher price.
Otherwise, hey, better medical technology thanks to 3d printing is good for everyone o
#This new high-power diamond laser can cut steel Although lasers based on diamond have been around around for several years,
they have never been very powerful. That beginning to change now as new CVD fabrication methods provide larger,
and purer, diamonds. Researchers from the Fraunhofer Institute for Applied Optics in Germany, and the MQ Photonics Research Centre in Australia, have built just a diamond laser with 20 times more power than anything yet to date.
The ability to slice through steel has always been the benchmark for cutting power. With 380 Watts@1240nm, the new laser has enough oomph to handle the job.
While lesser lasers have made similar claims without the actual watts behind them no amount of focussing
or pulse compression can make the task worthwhile. In other words, if your depth of focus is so tight that the sweet spot for cutting is barely thicker than a foil,
Diamond optics can not only handle the heat, but can also transfer it away from the hot zone faster that just about anything else.
The new diamond lasers make use of something known as Raman conversion to shift light to wavelengths that are long enough to be absorbed efficiently by steel.
they won deposit enough energy for cutting. In doped glass fibers, the aman gainis usually limited by line broadening effects.
Furthermore, the wavelength range of these fibers is restricted to the transparency of silica. The release stories for this laser mention that the infrared wavelengths used here are safer for the eye than either visible or UV radiation.
anything that has significant amounts of water is a potential absorber of IR energy across a fairly wide band.
with many noting that the new diamond laser is equal to 00,000 laser pointers. In light of the ample variance in both wavelength and power of pointer devices, those kinds of comparisons should probably be taken as rough.
Diamond lasers can potentially unleash more than just new cutting or machining technologies. Since silicon doesn reflect x-rays
Diamond-based x-ray lasers, on the other hand, would be a whole new ball game. CVD diamond still has its costs,
but they are rapidly falling while output quality is rising. It would seem that these trends should soon make off-the-shelf diamond lasers fairly commonplace a
#Accidental nanoparticles could let lithium ion batteries live another day A new study from MIT could keep lithium ion battery technology on the track for another few laps,
allowing further improvements while we wait for a fundamentally better solution to arrive. The breakthrough comes from an accidentally created synthetic metal nanoparticle that could solve some of the oldest problems for batteries.
Their testing shows that the nanoparticles could allow up to four times the charge retention after a long lifetime of use,
meaning devices could last longer and create far less unnecessary pollution. Not long ago scientists discovered that the main reason lithium ion batteries lose their capacity over many charge-discharge cycles has to do with expansion and contraction of the graphite electrodes at either end.
When electron-laden lithium ion diffuse across this gap and offload their electrons at the other side,
they stick to the electrode there, and can snap off as the whole thing expands and contracts. This removes some lithium ions from the system,
thus reducing the total available charge in the battery. This expansion problem is one of the reasons graphite has been used for so long
since it undergoes relatively little change throughout the battery use. In particular, aluminum has been a frequent candidate to replace graphite,
but tends to get discarded because it expands and contracts too much, and because it builds up an unhelpful coating
when exposed to air. Researchers from MIT were attempting to address this problem with different treatments for aluminum nanoparticles
and that work led them to bathe nanoparticles in a mixture of sulfuric acid and titanium oxysulfate,
with the intention of replacing the aluminum oxide coating that results from reaction with the air with a more practical coating of titanium oxide.
The issue arose when the team accidentally left a sample of aluminum in the bath for several hours longer than their technique required.
This resulted in an unforeseen egg-like nanoparticle design, in which a olkof aluminum is covered in a hellof titanium dioxide.
What important is that there is some space between the yolk and the shell (where the metaphorical hitewould go),
The delay in removing the aluminum from the chemical bath did not result in the shell around the aluminum core
but rather the shrinking of that core to a olkwith the all-important internal space. Though the team had meant not to create that unintentional chemical product,
What is clear is need that lithium ion batteries a breakthrough like this to keep moving further into people lives.
Charge-discharge capacity has a lot to do with the lifetime costs of things like electric cars if you could regularly drive an all-electric car for several years without much real risk of having to replace the battery pack,
electric cars would become much more affordable over their full lifespans. Fully alternative technologies, from carbon-based batteries to supercapacitors to mini-nuclear charging,
have been predicted to kill lithium ion for many years running, at this point Ie made the prediction myself, more than once.
What I think is underestimated often is the sheer install base of the technology, partially with customers,
Though Elon musk insists it will be at least somewhat modular to accept newer battery technologies the Tesla Gigafactory is built to create lithium ion batteries;
there is a significant economic incentive to keep improving lithium ion batteries, and to put off a large-scale switch as long as possible.
How long that stalling process can possibly continue will depend on how rapidly our power demands increase over time,
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