#Super-small needle technology for the brain However, one challenge is reducing the tissue/neuron damage associated with needle penetration, particularly for chronic insert experiment and future medical applications.
and other biological tissues because of needle buckling or fracturing on penetration. A research team in the Department of Electrical and Electronic Information Engineering
and the Electronics-Inspired Interdisciplinary Research Institute (EIIRIS) at Toyohashi University of Technology has developed a methodology to temporarily enhance the stiffness of a long,
which dissolves upon contact with biological tissue. Silk fibroin is used as the dissolvable film because it has high biocompatibility,
and is known a biomaterial used in implantable devices.""We investigated preparation of a silk base scaffold for a microneedle, quantitatively analyzed needle stiffness,
and evaluated the penetration capability by using mouse brains in vitro/in vivo. In addition, as an actual needle application, we demonstrated fluorescenctce particle depth injection into the brain in vivo,
and confirm that by observing fluorescenctce confocal microscope"explained the first author, master's degree student Satoshi Yagi,
and co-author Phd candidate Shota Yamagiwa. The leader of the research team, Associate professor Takeshi Kawano said:"
"Preparation of the dissolvable base scaffold is very simple, but this methodology promises powerful tissue penetrations using numerous high-aspect-ratio flexible microneedles,
including recording/stimulation electrodes, glass pipettes, and optogenetic fibers.""He added:""This has the potential to reduce invasiveness drastically
#Narrowing the gap between synthetic and natural graphene Media-friendly Nobel laureates peeling layers of graphene from bulk graphite with sticky tape may capture the public imagination,
Arrayflagship-affiliated physicists from RWTH Aachen University and Forschungszentrum Jülich have together with colleagues in Japan devised a method for peeling graphene flakes from a CVD substrate with the help of intermolecular forces.
the first author of which is research student Luca Banszerus. Key to the process is the strong Van der waals interaction that exists between graphene and hexagonal boron nitride, another 2d material within
which it is encapsulated. The Van der waals force is the attractive sum of short-range electric dipole interactions between uncharged molecules.
Thanks to strong Van der waals interactions between graphene and boron nitride, CVD graphene can be separated from the copper
and transferred to an arbitrary substrate. The process allows for reuse of the catalyst copper foil in further growth cycles
Raman spectroscopy and transport measurements on the graphene/boron nitride heterostructures reveals high electron mobilities comparable with those observed in similar assemblies based on exfoliated graphene.
such as Microsoft's Kinect controller for video games, have become widely used 3-D sensors. Now, a new imaging technology invented by Carnegie mellon University and the University of Toronto addresses a major shortcoming of these cameras:
the inability to work in bright light, especially sunlight. The key is to gather only the bits of light the camera actually needs.
The researchers created a mathematical model to help program these devices so that the camera and its light source work together efficiently,
and only those rays,"said Srinivasa Narasimhan, CMU associate professor of robotics.""We don't need new image-processing algorithms
and we don't need extra processing to eliminate the noise, because we don't collect the noise.
This is all done by the sensor.""One prototype based on this model synchronizes a laser projector with a common rolling-shutter camera-the type of camera used in most smartphones
-so that the camera detects light only from points being illuminated by the laser as it scans across the scene.
including medical imaging, inspection of shiny parts and sensing for robots used to explore the moon and planets.
It also could be incorporated readily into smartphones. The researchers will present their findings today at SIGGRAPH 2015, the International Conference on Computer graphics and Interactive Techniques,
in Los angeles. Depth cameras work by projecting a pattern of dots or lines over a scene.
if only briefly, noted Kyros Kutulakos, U of T professor of computer science.""Even though we're not sending a huge amount of photons, at short time scales,
we're sending a lot more energy to that spot than the energy sent by the sun,
if other camera hardware is used, the mathematical framework developed by the team can compute energy-efficient codes that optimize the amount of energy that reaches the camera.
In addition to enabling the use of Kinect-like devices to play videogames outdoors, the new approach also could be used for medical imaging,
such as skin structures that otherwise would be obscured when light diffuses as it enters the skin.
Likewise, the system can see through smoke despite the light scattering that usually makes it impenetrable to cameras.
University Professor of Robotics at CMU, said the system offers a number of advantages for extraterrestrial robots.
noting that a robot's sensors expend a relatively large amount of energy because they are always on."
Arrayin addition to Narasimhan and Kutulakos, the research team included Supreeth Achar, a CMU Ph d. student in robotics,
and Matthew O'Toole, a U of T Ph d. computer science student. The research was supported by the National Science Foundation, the U s army Research Laboratory,
Arrayabout University of Toronto: The University of Toronto has assembled one of the strongest research and teaching faculties in North america, presenting top students at all levels with an intellectual environment unmatched in breadth
and depth on any other Canadian campus. U of T faculty co-author more research articles than their colleagues at any university in the US or Canada other than Harvard.
As a measure of impact, U of T consistently ranks alongside the top five U s. universities whose discoveries are cited most often by other researchers around the world.
The U of T faculty is recognized also widely for its teaching strengths and commitment to graduate supervision.
Established in 1827 the University of Toronto today operates in downtown Toronto, Mississauga and Scarborough,
as well as in nine renowned academic hospitals s
#Scientists determine how antibiotic gains cancer-killing sulfur atoms In a discovery with implications for future drug design,
scientists have shown an unprecedented mechanism for how a natural antibiotic with antitumor properties incorporates sulfur into its molecular structure, an essential ingredient of its antitumor activity.
This new discovery could open the way to incorporating sulfur into other natural products, potentially advancing new therapies for indications beyond cancer."
"We found a novel mechanism to incorporate sulfur into natural products, which is unprecedented,"Shen said."
"Until our study, we didn't really know how sulfur atoms are incorporated into a natural product--now we have discovered a new family of enzymes
A number of compounds that contain sulfur have proven useful in the treatment of conditions ranging from acne and eczema to arthritis and cancer."
"With many other natural products, sulfur could add other therapeutic properties. This is the beauty of fundamental research--it lays the foundation to create novel technologies that enable innovative translational research with implications far beyond the original discovery."
"The study links a family of enzymes--molecules that act as biological catalysts--known as polyketide synthases (PKS) directly to a complex series of chemical reactions that ultimately add sulfur to leinamycin, a member of the polyketide family of natural products."
#Engineering a permanent solution to genetic diseases In his mind, Basil Hubbard can already picture a new world of therapeutic treatments for millions of patients just over the horizon.
It's a future in which diseases like muscular dystrophy, cystic fibrosis and many others are treated permanently through the science of genome engineering.
Thanks to his latest work, Hubbard is bringing that future closer to reality. Hubbard's research, published in the journal Nature Methods, demonstrates a new technology advancing the field of genome engineering.
The method significantly improves the ability of scientists to target specific faulty genes and then"edit"them, replacing the damaged genetic code with healthy DNA."
"There is a trend in the scientific community to develop therapeutics in a more rational fashion,
rather than just relying on traditional chemical screens, "says Hubbard, an assistant professor of pharmacology in the University of Alberta's Faculty of medicine & Dentistry."
"We're moving towards a very logical type of treatment for genetic diseases, where we can actually say,
'Your disease is caused by a mutation in gene X, and we're going to correct this mutation to treat it'."
'"In theory, genome engineering will eventually allow us to permanently cure genetic diseases by editing the specific faulty gene (s)."Genome engineering involves the targeted, specific modification of an organism's genetic information.
Much like how a computer programmer edits computer code, scientists could one day replace a person's broken
or unhealthy genes with healthy ones through the use of sequence-specific DNA BINDING PROTEINS attached to DNA-editing tools.
The field has made large strides over the last two decades and may one day revolutionize medical care.
One of the obstacles still to be addressed in the field before it can see widespread use in humans is how to ensure the proteins only affect the specific target genes in need of repair.
With current technologies, the proteins bind to and edit the correct genes the vast majority of the time,
but more improvements are needed to ensure off-target genes aren't modified--a result that could potentially cause serious health problems itself.
Through his research, undertaken as a postdoctoral fellow in the lab of David R. Liu at Harvard university,
"Currently much of the research in the field of genome engineering is focused on treating monogenic diseases--diseases that involve a single gene--as they're much easier for researchers to successfully target.
Examples include diseases such as hemophilia, sickle cell anemia, muscular dystrophy and cystic fibrosis. While the field is still in its relative infancy,
He hopes his current work will play a role in helping genome engineering reach its full potential
gene editing could possibly provide a permanent cure for a lot of different diseases, "says Hubbard.""We still have to overcome many hurdles but
I think this technology definitely has the potential to be transformative in medicine
#Mechanism of epidemic bacterial disease identified Through identification of increased toxin production by epidemic forms of group A streptococcus (the"flesh-eating"bacterium),
for the first time scientists are able to pinpoint the molecular events that contribute to large intercontinental epidemics of disease.
The study was based on sequencing almost 5, 000 group A streptococcus genomes collected over decades.
Researchers from Houston Methodist Research Institute, Houston Methodist Hospital, institutions in Finland and Iceland, and the U s. National Institute of Allergy and Infectious diseases report their discoveries and implications for future studies of epidemic diseases in an upcoming Journal of Clinical Investigation (early online).
According to James M. Musser, M d.,Ph d.,principal investigator of the study and chair of the Department of Pathology and Genomic medicine at the Houston Methodist Research Institute, the collaborative research showed, at the precise nucleotide level,
genetic changes that contributed to large epidemics of group A streptococcus (GAS).""These findings now give us the opportunity to begin to develop new translational medicine tools
and strategies,"said Musser.""We can use this information to develop novel therapeutics, advanced diagnostic techniques and new ways to prevent,
or dampen, epidemics.""According to the World health organization, GAS causes more than 600 million cases of human disease every year.
The majority of cases are group A streptococcus pharyngitis, more commonly known as strep throat. But group A strep is also the major cause of preventable childhood heart disease caused by rheumatic fever and rheumatic heart disease.
On the far end of the infection severity spectrum, group A streptococcus also causes necrotizing fasciitis("flesh-eating"disease), an infection with a high mortality rate.
The collaborating team of international scientists found that group A streptococcus was an excellent model organism to study the molecular basis of epidemic bacterial infections.
Researchers have known for more than a century that this pathogenic bacterium can cause epidemics but no one has been able to fully address the cause.
Now with next generation sequencing, scientists are able to sequence the entire genome of the bacteria,
just as is done in humans. Group A streptococcus was selected as the model organism for study due to the availability of comprehensive strain samples collected over decades,
and its relatively small genome, which allows the genome of thousands of strains to be sequenced completely relatively rapidly.
The researchers'original hypothesis, which turned out to be correct, was that changes in the genetic make-up of the GAS pathogen had underpinned new epidemics.
To address this hypothesis the collaborating international team sequenced the genome of thousands of disease-causing strains,
precisely defining every base pair mutation in the strains.""The surprise was that the changes involved alterations in the genes encoding two potent toxins that contribute to human infections,
"said Musser, who is director for the Center for Molecular and Translational Human Infectious disease Research at Houston Methodist.
The researchers found that in the epidemic form of group A streptococcus, which can manifest as necrotizing fasciitis,
or"flesh-eating"disease, there were two significant and crucial changes within the regulatory region of the epidemic strains.
The regulatory region identified controls how two key toxin-encoding genes are transcribed and the toxic proteins made.
These specific genetic changes result in the creation of single nucleotide polymorphisms or SNPS. Musser's team found that two of those SNPS result in significantly increased production of two important toxins that harm humans called streptolysin O and NAD-glycohydrolase.
The third SNP creates a form of one of those toxins that becomes more active than the original form.
All three of these SNPS contributed to building a pathogenic organism that is a more virulent machine capable of causing epidemics."
"Think about the thermostat in your house that controls temperature. If you want to make your house hotter,
or if group A streptococcus wants to make itself'hotter,'that is, more virulent, it turns up the heat by making more of these two toxins that harm human cells,
"said Musser. Musser and team are hopeful findings from their model study will allow other infectious disease researchers to use analogous strategies that focus on other pathogens, like Staphylococcus aureus (the leading cause of skin and soft-tissue infections),
and antibiotic-resistant bacteria such as Klebsiella pneumonia or Escherichia coli i
#Device may detect urinary tract infections faster Sepsis is a major killer and accounts for about half of the hospital deaths in the US by some estimates.
Hospital patients often acquire urinary tract infections via infected catheters and so untreated infections are a huge problem faced by healthcare providers around the world.
Early diagnosis could save lives and reduce healthcare costs. With this motivation in mind, a team of researchers in Germany and Ireland set out to speed up the detection process for bacteria that cause urinary tract infections.
Arraytheir medical diagnostics device is designed to harness centrifugal force--akin to the circular swing of A chair-o-Plane"carnival ride
in which a fast rotation creates a force that causes the seats to drift radially away from the ride's center--to capture the tiny bacteria directly from patients'samples of bodily fluidsn this case, urine.
The work involves extremely small sample sizes, on the scale of a small raindrop, so the device needed to be a microfluidic one."
"Our device works by loading a few microliters of a patient's urine sample into a tiny chip,
which is rotated then with a high angular velocity so that any bacteria is guided by centrifugal force through microfluidic channels to a small chamber where'V-cup capture units'collect it for optical investigation,
"explained Ulrich-Christian Schröder, a Ph d. student at the Jena University Hospital and Leibniz Institute of technology in Germany.
The team's concept then adds Raman spectroscopy to its centrifugal microfluidic platform.""Raman spectroscopy uses the way light interacts with matter to produce'unique scattering,'the equivalent of a molecular fingerprint,
which can then be used to identify the types of bacteria present, "said Ute Neugebauer, group leader at the Jena University Hospital and Leibniz Institute of technology.
What exactly does the team's medical device detect?""In our pilot study, we were able to identify Escherichia coli (more commonly known as E coli)
and Enterococcus faecalis--two species known to cause urinary tract infections--within 70 minutes, directly from patients'urine samples,"said Schröder.
The speedy diagnosis marks a tremendous reduction in the wait time compared to the lengthy lag--often 24 hours
or more--associated with methods routinely used to identify bacteria and diagnose urinary tract infections today, so the team's device shows great potential for improving the future of medical diagnostics.
The team envisions general practitioners, a k a. family doctors using the device to rapidly --while a patient waits--identify the bacteria causing an infection directly within the patient's bodily fluid
so that they can prescribe the appropriate medication and treatment.""Our pilot study brings us a step closer toward realizing this vision,
"said Neugebauer. The team will continue toward its goal of developing an easy-to-use spectroscopy-based point-of-care medical device for fast and reliable diagnostics."
"The next step will involve implementing antibiotic susceptibility testing and automating the sample pre-treatment steps,
"Neugebauer explained.""Our ultimate vision is to apply the concepts behind our device to enable diagnostics devices for use with other bodily fluids. u
#Droplets levitate on a cushion of blue light Arraythe floating effect is similar to Leidenfrost levitation--in
which droplets dance on a hot vapor cushion. But by creating the vapor with a strong jolt of electricity instead of heat,
the researchers found they could ionize the gas into a plasma that glowed a soft blue light."
"This method is probably an easy and original way to make a plasma, "said Cedric Poulain, a physicist at The french Alternative energies and Atomic energy commission.
Poulain speculates that the deformability of a liquid drop would let the researchers rig up a device to move the plasma along a surface,
but he admits that such applications were far from his and his colleagues'minds when they first conceived the experiment.
At first, the researchers wanted to explore the limits of the analogy between the boiling phenomenon and water electrolysis,
which is the breakup of water into hydrogen and oxygen gases by an electric current. As an example of boiling behavior
Poulain described the case of a liquid droplet at the surface of a hot pan.
If the pan temperature is just above 100 degrees Celsius, the drop spreads and water vapor bubbles grow at the pan surface.
because they study an event called"boiling crisis"in nuclear power plant steam generators. If the core of a nuclear reactor gets too hot,
bubbles in the cooling water can suddenly coalesce to form a vapor film that limits further heat transfer
Arrayin their lab, Poulain and his colleagues devised a setup to run electricity through conductive droplets and film the droplets'behavior at high speed..
which conducts electricity, above a metal plate and applied a voltage across the drop. When the drop touched the plate,
electricity began to flow, and the water in the hydrochloric acid solution started to break down into hydrogen and oxygen gas.
but further analysis revealed that the gaseous cushion was in fact mostly water vaporized by energy from the electric current.
what gives rise to the very high electric field necessary to generate a long-term and dense plasma with little energy.
Arraythe researchers next plan to analyze the composition of the plasma layer. They say it appears to be a superposition of two types of plasma that is not well understood.
They will also study the fast dynamics at the bottom of the drop just as the sparks begin to fly,
which should yield additional insights into the plasma. Although plasma dynamics may seem far removed from the problem of film boiling in nuclear reactors,
Poulain is happy about the path the curiosity-driven research has taken the team.""It's very exciting,
"he said of the team's foray into plasma levitation n
#Paving the way for a faster quantum computer Since its conception, quantum mechanics has defied our natural way of thinking,
Quantum logic gates are the basic building blocks of a quantum computer, but constructing enough of them to perform a useful computation is difficult.
In the usual approach to quantum computing, quantum gates are applied in a specific order, one gate before another.
But it was realized recently that quantum mechanics permits one to"superimpose quantum gates.""If engineered correctly, this means that a set of quantum gates can act in all possible orders at the same time.
Surprisingly, this effect can be used to reduce the total number of gates required for certain quantum computations.
All orders at once A team led by Philip Walther recently realized that superimposing the order of quantum gates, an idea
which was designed theoretically by the group of Caslav Brukner, could be implemented in the laboratory. In a superposition of quantum gate orders, it is impossible--even in principle--to know
if one operation occurred before another operation, or the other way around. This means that two quantum logic gates A and B can be applied in both orders at the same time.
In other words, gate A acts before B and B acts before A. The physicists from Philip Walther's group designed an experiment in
which the two quantum logic gates were applied to single photons in both orders. The results of their experiment confirm that it is impossible to determine which gate acted first
--but the experiment was not simply a curiosity.""In fact, we were able to run a quantum algorithm to characterize the gates more efficiently than any previously known algorithm,
"says Lorenzo Procopio, lead author of the study. From a single measurement on the photon, they probed a specific property of the two quantum gates thereby confirming that the gates were applied in both orders at once.
As more gates are added to the task, the new method becomes even more efficient compared to previous techniques.
The Way Forward This is the first time that a superposition of quantum gates has been implemented in the lab. At the same time
it was used to successfully demonstrate a new kind of quantum computing. The scientists were able to accomplish a computation with an efficiency that cannot be achieved within the old scheme of quantum computing.
This work opens a door for future studies on novel types of quantum computation. Although its full implications are still unknown,
this work represents a new, exciting way to connect theoretical research on the foundations of physics to experimental quantum computing g
#Quantum quarry: Scientists unveil new technique for spotting quantum dots to make high performance nanophotonic devices A quantum dot should produce one and only one photon--the smallest constituent of light--each time it is energized,
and this characteristic makes it attractive for use in various quantum technologies, such as secure communications.
However, the trick is in finding them. While they appear randomly, in order for the dots to be need useful they to be located in a precise relation to some other photonic structure,
be it a grating, resonator or waveguide, which will enable control of the photons that the quantum dot generates.
However finding the quantum dots--they're just about 10 nanometers across--is no small feat. Now, researchers working at the National Institute of Standards and Technology (NIST) in the United states,
in collaboration with the universities of Southampton (UK) and Rochester (US), have developed a simple new technique for locating them
and used it to create high-performance single photon sources. Array"This is a first step towards providing accurate location information for the manufacture of high performance quantum dot devices,
"says NIST physicist Kartik Srinivasan.""So far, the general approach has been statistical--make a lot of devices
and end up with a small fraction that work --but our camera-based imaging technique instead seeks to map the location of the quantum dots first,
and then uses that knowledge to build optimized light-control devices in the right place."
"Dr Luca Sapienza, from the University's Quantum Light and Matter group, says:""This new technique is sort of a twist on a red-eye reducing camera flash,
where the first flash causes the subject's pupils to close and the second illuminates the scene."
"In their setup, instead of xenon-powered flash the team used two LEDS. One LED activates the quantum dots
when it flashes (you could say this LED gives the quantum dots red eye). At the same time, a second, different color LED flash illuminates metallic orientation marks placed on the surface of the semiconductor wafer the dots are embedded in.
Then a sensitive camera snaps a 100-micrometer by 100-micrometer picture. By cross-referencing the glowing dots with the orientation marks,
the researchers can determine the dots'locations with an uncertainty of less than 30 nanometers. Their coordinates in hand, scientists can then tell the computer-controlled electron beam lithography tool to place any structure the application calls for in its proper relation to the quantum dots,
resulting in many more usable devices. Using this technique the researchers demonstrated grating-based single photon sources in
which they were able to collect 50 per cent of the quantum dot's emitted photons, the theoretical limit for this type of structure.
They also demonstrated that more than 99 per cent of the light produced from their source came out as single photons.
Such high purity is partly due to the fact that the location technique helps the researchers to quickly survey the wafer (10,000 square micrometers at a time) to find regions where the quantum dot density is especially low-only about one per 1
000 square micrometers. This makes it far more likely that each grating device contains one--and only one--quantum dot.
This work was performed in part at NIST's Center for Nanoscale Science and Technology (CNST), a national user facility available to researchers from industry, academia and government t
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