#Wireless data delivery over active TV channels tested Rice university engineers have demonstrated the first system that allows wireless data transmissions over UHF channels during active TV broadcasts.
If the technology were incorporated into next-generation TVS or smart remotes, it could significantly expand the reach of so-called"super Wi-fi"networks in urban areas."
"Due to the popularity of cable, satellite and Internet TV, the UHF spectrum is one of the most underutilized portions of the wireless spectrum in the United states,
"said lead researcher Edward Knightly.""That's a bitter irony because the demand for mobile data services is expected to grow tenfold in the next five years,
and the UHF band is suited perfectly for wireless data.""Knightly, professor and department chair of electrical
and computer engineering and director of the Rice Wireless Network Group, said the UHF spectrum, which ranges from 400 to 700 megahertz,
is called often the"beachfront property"of the wireless spectrum. Unlike the higher frequency signals used for existing Wi-fi hotspots,
UHF signals carry for miles and are blocked not by walls or trees. Because of these advantages, wireless data hotspots that use UHF are referred often to as"super Wi-fi."
"In the U s.,TV broadcasters have been given preferential access to the UHF spectrum for more than 50 years.
If no TV broadcaster has laid claim to a UHF channel, the Federal Communications Commission allows secondary users to transmit wireless data on that channel,
provided that the transmissions do not interfere with TV broadcasts in any part of the UHF spectrum.
The rules governing this secondary access are referred often to as"TV white space"rules in reference to the industry term for used or blank portions of the TV spectrum."
"Unfortunately, in the most densely populated areas of the country, where the need for additional wireless data services is the greatest,
the amount of available white space is limited extremely, "Knightly said.""In our most recent tests in Houston, one channel is open in parts of the city
and none are available in others. This is fairly typical of a large U s. urban area.""Though most of the UHF band is taken already in U s. cities,
it is largely underutilized. According to a 2014 report by the TV rating company Nielsen, fewer than 10 percent of U s. households rely on over-the-air broadcasts for TV programming.
To demonstrate that wireless service providers could make use of the UHF spectrum without interfering with TV broadcasters,
Knightly and Rice graduate student Xu Zhang developed a technology called"Wi-fi in Active TV Channels,
"or WATCH, and received FCC approval to test it at the Rice campus in 2014.
WATCH requires no coordination with or changes to legacy TV transmitters. Instead TV signals are broadcast as normal
and the WATCH system actively monitors whenever a nearby TV is tuned to a channel to avoid interfering with reception.
The technology to allow this comes in two parts. One aspect of WATCH monitors TV broadcasts on a channel and uses sophisticated signal-canceling techniques to insert wireless data transmissions into the same channel;
that eliminates TV broadcasts from interfering with the super Wi-fi data signals being sent to computer users,
Knightly said. The other aspect of WATCH is dedicated to making certain that data transmissions do not interfere with TV reception;
this part of the technology would require TVS to report when they are being tuned to a UHF channel,
Knightly said. In practice, this could be accomplished with either smart TV remotes or next-generation TV SETS.
In the tests at Rice, Zhang constructed a"smart-remote"app that reported whenever a test television in the lab was tuned to a UHF channel.
When that happened, the WATCH system automatically shifted its data transmissions to another part of the UHF spectrum that wasn't being used."
"Our tests showed that WATCH could provide at least six times more wireless data compared with situations where we were limited only to the traditionally available white-space spectrum,
"Knightly said. With WATCH in use, Knightly said it took a fraction of a second longer than normal to tune in a UHF TV broadcast on the test television.
While the increment could be measured--it was less than a 5 percent increase--it was almost imperceptible to the person switching channels,
he said. Zhang and Knightly's report on the research, titled"WATCH: Wi-fi in Active TV Channels,"won best-paper honors last month at Association of Computing Machinery's Mobihoc 2015 conference in Hangzhou, China.
Knightly said technology like WATCH will become increasingly important as the demand for wireless data services increases and the number of broadcast TV viewers decreases.
For example, a 2014 Cisco report found that nearly a half-billion mobile devices with data connections had been added to the global supply within the previous year, bringing the global total to 7. 4 billion--a bit more than number of people On earth, according to the U s. Census bureau.
Of the 7. 4 billion data-connected devices Cisco found that more than a quarter were used smartphones,
which an estimated 22 times more data than nonsmart devices.""Allowing the UHF spectrum to be used inefficiently makes little sense today
and will make even less sense in the future, "Knightly said.""There are already more people in the United states who require mobile data services than there are people using broadcast-only TV.
By showing that these two communities can coexist, we hope to spur innovation and a public debate about how this valuable resource could be used
#Polymer mold makes perfect silicon nanostructures Using molds to shape things is as old as humanity.
In the Bronze age, the copper-tin alloy was melted and cast into weapons in ceramic molds.
Today, injection and extrusion molding shape hot liquids into everything from car parts to toys.
For this to work, the mold needs to be stable while the hot liquid material hardens into shape.
In a breakthrough for nanoscience, Cornell polymer engineers have made such a mold for nanostructures that can shape liquid silicon out of an organic polymer material.
This paves the way for perfect 3-D, single crystal nanostructures. The advance is from the lab of Uli Wiesner, Professor of Engineering in the Department of Materials science and engineering,
whose lab previously has led the creation of novel materials made of organic polymers. With the right chemistry, organic polymers self-assemble,
and the researchers used this special ability of polymers to make a mold dotted with precisely shaped and sized nanopores.
Normally, melting amorphous silicon, which has a melting temperature of about 2, 350 degrees, would destroy the delicate polymer mold,
which degrades at about 600 degrees. But the scientists in collaboration with Michael Thompson, associate professor of materials science and engineering, got around this issue by using extremely short melt periods induced by a laser.
The researchers found the polymer mold holds up if the silicon is heated by laser pulses just nanoseconds long.
At such short time scales, silicon can be heated to a liquid, but the melt duration is so short the polymer doesn't have time to oxidize
and decompose. They essentially tricked the polymer mold into retaining its shape at temperatures above its decomposition point.
When the mold was etched away the researchers showed that the silicon had been shaped perfectly by the mold.
This could lead to making perfect, single-crystal silicon nanostructures. They haven't done it yet,
but their Science paper shows it's possible. In work published in 2010, Wiesner and colleagues showed the pathway for this process,
using an oxide mold. Wiesner called the breakthrough"beautiful"and a possibly fundamental insight into studying nanoscale materials.
In materials science, the goal is always to get well-defined structures that can be studied without interference from material defects.
Most self-assembled nanostructures today are either amorphous or polycrystalline--made up of more than one piece of a material with perfect order.
It's hard to judge whether their properties are due to the nanostructure itself or whether they're dominated by defects in the material.
Discovery of single-crystal silicon--the semiconductor in every integrated circuit--made the electronics revolution possible.
It took cutting single crystals into wafers to truly understand silicon's semiconducting properties. Today, nanotechnology allows incredibly detailed nanoscale etching, down to 10 nanometers on a silicon wafer.
But nanofabrication techniques like photolithography, in which a polymeric material is written with a structure that is etched into the silicon,
hits its limits when it comes to 3-D structures. Semiconductors like silicon don't self-assemble into perfectly ordered structures like polymers Do it's almost unheard of to get a 3-D structured single crystal of a semiconductor.
To make single crystal nanostructures there are two options: multiple etching or molding. Wiesner's group now has made the mold.
The way they made the mold was itself a breakthrough. They had learned previously to self-assemble highly ordered,
porous nanomaterials using specially structured molecules called block copolymers. They first used a carbon dioxide laser in Thompson's lab to"write"the nanoporous materials onto a silicon wafer.
A film, spin-coated on the wafer, contained a block copolymer, which directed the assembly of a polymer resin.
Writing lines in the film with the laser, the block copolymer decomposed, acting like a positive-tone resist,
while the negative-tone resin was left behind to form the porous nanostructure. That became the mold."
"We demonstrated that we can use organic templates with structures as complicated as a gyroid, a periodically ordered cubic network structure,
and'imprint'it onto molten silicon, which then transforms into crystalline silicon, "Wiesner said.""Having the ability to mold the workhorse of all electronics, silicon,
into intricate shapes is unprecedented, "said Andy Lovinger, a program director in the materials research division at the National Science Foundation, which funded Wiesner's research."
"This beautiful work shows how it could be done by taking advantage of the unique design properties offered by polymeric materials
#New compounds may treat depression rapidly with few side effects Array"Our results open up a whole new class of potential antidepressant medications,
"said Dr. Thompson.""We have evidence that these compounds can relieve the devastating symptoms of depression in less than one day,
and can do so in a way that limits some of the key disadvantages of current approaches."
"Currently, most people with depression take medications that increase levels of the neurochemical serotonin in the brain.
In addition, even when these drugs work, they typically take between three and eight weeks to relieve symptoms.
As a result, patients often suffer for months before finding a medicine that makes them feel better.
The researchers tested the compounds in rats that were subjected to chronic mild stress that caused the animals to act in ways that resemble human depression.
"This work underscores the importance of basic research to our clinical future, "said Dean E. Albert Reece, MD, Phd, MBA,
who is also the vice president for Medical Affairs, University of Maryland, and the John Z. and Akiko K. Bowers Distinguished Professor and Dean of the School of medicine."
"Dr. Thompson's work lays the crucial groundwork to transform the treatment of depression and reduce the tragic loss of lives to suicide
#Nanoscale light-emitting device has big profile University of Wisconsin-Madison engineers have created a nanoscale device that can emit light as powerfully as an object 10,000 times its size.
It's an advance that could have huge implications for everything from photography to solar power.
In a paper published July 10 in the journal Physical Review Letters, Zongfu Yu, an assistant professor of electrical and computer engineering,
and his collaborators describe a nanoscale device that drastically surpasses previous technology in its ability to scatter light.
They showed how a single nanoresonator can manipulate light to cast a very large"reflection."
"The nanoresonator's capacity to absorb and emit light energy is such that it can make itself--and, in applications,
other very small things--appear 10,000 times as large as its physical size.""Making an object look 10,000 times larger than its physical size has lots of implications in technologies related to light,
"Yu says. The researchers realized the advance through materials innovation and a keen understanding of the physics of light.
amplifying itself as the surrounding environment manipulates the physical properties of its wave energy. The researchers took advantage of this by creating an artificial material in
a Ph d. student in Yu's group and lead author of the paper. Much as a very thin string on a guitar can absorb a large amount of acoustic energy from its surroundings
and begin to vibrate in sympathy, this one very small optical device can receive light energy from all around
Given the nanoresonator's capacity to absorb large amounts of light energy, the technology also has potential in applications that harvest the sun's energy with high efficiency.
In addition, Yu envisions simply letting the resonator emit that energy in the form of infrared light toward the sky,
which is very cold. Because the nanoresonator has a large optical cross-section--that is, an ability to emit light that dramatically exceeds its physical size--it can shed a lot of heat energy,
making for a passive cooling system.""This research opens up a new way to manipulate the flow of light,
#Better memory with faster lasers By studying the effect of femtosecond laser pulses on the types of materials used to make DVDS,
researchers made a discovery that could one day lead to better information storage in computers.
These two states represent 0s and 1s of digital data.""Today, nanosecond lasers--lasers that pulse light at one-billionth of a second--are used to record information on DVDS and Blu-ray disks,
by driving the material from one state to another, "explains Giovanni Vanacore, a postdoctoral scholar and an author on the study.
The speed with which data can be recorded is determined both by the speed of the laser--that is,
by the duration of each"pulse"of light--and by how fast the material itself can shift from one state to the other.
one 0 or 1, every nanosecond,"says Jianbo Hu, a postdoctoral scholar and the first author of the paper."
"To study this, the researchers used their technique, ultrafast electron crystallography. The technique, a new development--different from Zewail's Nobel prize-winning work in femtochemistry, the visual study of chemical processes occurring at femtosecond scales--allowed researchers to observe directly the transitioning atomic configuration of a prototypical phase-change
material, germanium telluride (Gete), when it is hit by a femtosecond laser pulse. In UEC, a sample of crystalline Gete is bombarded with a femtosecond laser pulse,
--and to how fast data can be recorded, regardless of the laser speeds used.""Even if there is a laser faster than a femtosecond laser,
"Despite revealing such limits, the research could one day aid the development of better data storage for computers,
Right now, computers generally store information in several ways, among them the well-known random-access memory (RAM) and read-only memory (ROM.
RAM, which is used to run the programs on your computer, can record and rewrite information very quickly via an electrical current.
whenever the computer is powered down. ROM storage, including CDS and DVDS, uses phase-change materials and lasers to store information.
Although ROM records and reads data more slowly, the information can be stored for decades. Finding ways to speed up the recording process of phase-change materials
and understanding the limits to this speed could lead to a new type of memory that harnesses the best of both worlds.
and then rewrite a DVD. Although these applications could mean exciting changes for future computer technologies,
this work is also very important from a fundamental point of view, Zewail says.""Understanding the fundamental behavior of materials transformation is
The work was supported by the National Science Foundation and the Air force Office of Scientific research and was carried out in Caltech's Center for Physical Biology,
which is funded by the Gordon and Betty Moore Foundation n
#Liquid biopsy identifies mutations in colorectal cancer undetected in tissue biopsy The results of the trial were twofold:
liquid biopsy effectively unmasked different tumor-related mutations. More specifically, in a subgroup of 41 patients who had received previously anti-EGFR therapy,
it was revealed that they had acquired KRAS mutations during the course of their disease. Such accurate information is difficult to obtain using tissue biopsy
which could, in the absence of this data, lead to a selection of therapy which may not be the most appropriate for these patients.
Moreover, the study concludes that regorafenib is effective in patients with KRAS and PIK3CA mutations."
"This is the first large clinical trial to compare liquid versus conventional tissue biopsy data, and the results show the former (BEAMING technology) obtain more data on tumor mutation throughout the course of the disease,
enabling us to better target therapy to the specificities of patient's tumor; this could have a considerable impact on clinical practice,
as novel applications of this technology could be investigated further and developed,"says Josep Tabernero, Head of the Medical Oncology Department of Hospital Universitario Vall d'Hebron, Director of VHIO,
and Co-Director of the study. The majority of clinical studies published on the use of DNA in blood to determine tumor genotype,
have enrolled only a relatively small number of patients which limits the significance of the findings as well as the ability to research possible correlations between genotype and clinical outcome.
Furthermore, most studies evaluated a single gene (such as KRAS) and used technologies that are not commercially available.
The importance of the CORRECT trial is involved that it a large number of patients providing correlative analyses that showed clinical benefits of regorafenib in all the subgroups in
which mutations had been identified. Arraytumor genotype plays an important role in drug resistance in patients with metastatic colorectal cancer,
but the genotype obtained at diagnosis can vary after different treatment lines. Therefore, DNA analysis using liquid biopsy has clear advantages over DNA analysis with tissue biopsy
and is rapidly gaining importance and momentum in the oncology field. Liquid biopsy, also known as a blood-based biomarker test, is a fast, simple method for detecting RAS (KRAS and NAS) mutation status in tumors
as it only requires a blood test rather than a tissue biopsy or surgical procedure. Further, it also provides mutation status results in a matter of days,
helping to determine the most specific, targeted treatment in each case. It represents one more important step in realizing the true promise of precision medicine in oncology--the main focus behind research at VHIO which aims to both advance
and deliver targeted therapies tailored to the particularities of each tumor for an increasing number of patients.
Although there are still some important questions that will need to be resolved concerning liquid biopsy for example, the possibility that not all tumors release enough DNA into the blood for it to be detected,
as well as the difficulty of assigning a particular genotype for each particular tumor in patients with multiple metastases,
the CORRECT study shows that liquid biopsy could become an essential tool in clinical practice.
Arraycolorectal cancer is the second most common cancer in the world, with an estimated incidence rate of more than 1. 36 million new cases per year.
Around 694,000 people die from colorectal cancer every year, accounting for 8. 5%of all cancer deaths
ranking as the fourth most common cause of death from cancer. Approximately 55%of all colorectal cancer cases are diagnosed in the world's developed regions,
and the incidence and mortality rates are considerably higher among men than in women e
#Potential of blue LEDS as novel chemical-free food preservation technology A team of scientists from the National University of Singapore (NUS) has found that blue light emitting diodes (LEDS) have strong antibacterial
effect on major foodborne pathogens, and are most effective when in cold temperatures (between 4°C and 15°C) and mildly acidic conditions of around ph 4. 5. This opens up novel possibilities of using blue LEDS as a chemical-free food preservation method.
Acidic foods such as fresh-cut fruits and ready-to-eat meat can be preserved under blue LEDS in combination with chilling temperatures without requiring further chemical treatments that are needed commonly for food preservation.
These findings were published recently in the Food microbiology journal in June 2015 Enhancing blue LEDS'ability to deactivate bacteria
While LEDS are most commonly known as an energy saving light source, they have also been known to have an antibacterial effect.
Bacterial cells contain light sensitive compounds that adsorb light in the visible region of the electromagnetic spectrum (400-430 nm),
which IS LED mainly blue light. Exposure to illumination from blue LED light can hence start off a process within the cells that ultimately causes the cells to die.
Existing studies on the antibacterial effect of LED illumination mostly evaluated its efficacy by adding photosensitisers to the food samples
or by using very close distance of less than 2 cm between the bacterial suspension and LED light source.
These conditions would not be viable for application on food preservation. The NUS team, led by Assistant professor Yuk Hyun-Gyun,
from the Food science and Technology Programme at the NUS Faculty of science, is the first so far to show that factors such as temperature and ph levels,
which are typically related to food products, can affect the antibacterial effect of LEDS. In this study, the team placed three major foodborne pathogens--Listeria monocytogenes, Escherichia coli o157:
H7 and Salmonella typhimurium--under blue LED illumination, and varied the ph conditions from acidic to alkaline.
The team found that higher bacterial inactivation was achieved at acidic and alkaline ph conditions than when neutral.
In particular, acidic conditions were more detrimental than alkaline conditions for L. monocytogenes. For E coli O157:
H7 and S. Typhimurium, alkaline conditions were most detrimental although acidic conditions were also sufficiently effective in deactivating them.
A previous study in 2013 by the same team had looked also at the effect of temperature on blue LED's ability to deactivate bacterial cells
and found the antibacterial effect to be enhanced most in chilling temperatures. Asst Prof Yuk said,
"Taken together, our two studies point to a potential for preserving acidic foods in combination with chilling temperatures without chemical treatments.
This could meet the increasing demand for natural or minimally-processed foods without relying on chemicals such as acidulants and artificial preservatives to preserve food products."
"The team's findings can potentially be applied to food chillers or cold supply chain to preserve fresh-cut fruits,
ready-to-eat seafood such as sushi and smoked salmon, as well as chilled meat products. This technology can also be useful for retail settings,
spanning hawker centres, food courts to supermarkets, as well as for food suppliers.""The next step for us is to apply this LED TECHNOLOGY to real food samples such as fresh-cut fruits,
as well as ready-to-eat or raw sea foods and meats products, to investigate whether LED illumination can effectively kill pathogenic bacteria without deterioration of food products,
"said Asst Prof Yuk Y
#How the lung repairs its wounds Our lungs are exposed permanently to harmful environmental factors that can damage
or even destroy their cells. In a specific regenerative process these injured cells must be replaced as soon as possible.
In collaboration with colleagues from the Max Planck Institute (MPI) of Biochemistry, scientists at the Helmholtz Zentrum München have gained now,
The results have just been published in EMBO Molecular Systems Biology. According to the World health organization (WHO), lung diseases are the third most common cause of death worldwide:
toxic particles, infections, and chronic inflammatory responses pose a permanent threat to our lungs. To date, the regenerative mechanisms leading to healing of lung injury remain incompletely understood.
Since few to no causal therapies are in place for most lung diseases, it is important to understand how these healing processes,
which involve initial inflammation, fibrosis, and then resolution thereof, occur in the lung. Using novel mass spectrometry techniques,
an interdisciplinary team of scientists led by Prof. Matthias Mann, Director at the MPI of Biochemistry, and Prof.
Oliver Eickelberg, Chairman of the Comprehensive Pneumology Center (CPC) at the Helmholtz Zentrum München and University Hospital of the Ludwig-Maximilians-Universität
has succeeded now, for the first time, to quantify and profile dynamic changes in the composition of the lung tissue throughout the different phases of lung regeneration.
More than 8, 000 proteins examined When the pulmonary alveoli are damaged, various proteins are secreted into the extracellular space,
The findings of the research team will provide an important basis for further translational research on the development of pulmonary fibrosis*and chronic lung diseases in general,
and abundance of proteins in patients with lung fibrosis and healthy individuals and will therefore likely lead to new approaches for the treatment of chronic lung diseases in general and lung fibrosis in particular,
The research by the lab of Rice physicist Emilia Morosan has already been cited as a textbook example of how magnetism arises in metals.
This is not the kind of magnet one would stick to a refrigerator. Magnetic order only appears in Tiau
when the metal is cooled to 36 kelvins, about minus 395 degrees Fahrenheit.""Magnetization is a function of temperature,
"For common magnets, that temperature is generally hundreds of degrees Fahrenheit, way hotter than any kitchen.
But the energy and temperature scale in unconventional magnets, like the few that have no magnetic elements,
Tiau is only the third known itinerant magnetic metal made with no magnetic elements. The other two, both ferromagnets that activate their magnetic order at temperatures even colder than Tiau
toxic or required a high temperature that was not accessible in the lab.""We had to discard many candidate compounds,
who worked on the project for six years as a Rice graduate student. But electronic structure calculations showed a 1-to-1 mix of titanium
They also allow for handy things like electrical conductivity in metals. Atomic moments in local-moment ferromagnets--that is, common magnetic materials--align all of their spins in the same direction.
In an antiferromagnet, the atomic moments align in opposite directions. Morosan said it's important to know these extremes in magnetic behavior."
another Morosan lab graduate student and co-author of the paper.""This is the first time such an antiferromagnetic material has been discovered,
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