Culture

Hallucinations are spooky and, fortunately, fairly rare. But, a new study suggests, the real question isn't so much why some people occasionally experience them. It's why all of us aren't hallucinating all the time.

In the study, Stanford University School of Medicine neuroscientists stimulated nerve cells in the visual cortex of mice to induce an illusory image in the animals' minds. The scientists needed to stimulate a surprisingly small number of nerve cells, or neurons, in order to generate the perception, which caused the mice to behave in a particular way.

"Back in 2012, we had described the ability to control the activity of individually selected neurons in an awake, alert animal," said Karl Deisseroth, MD, PhD, professor of bioengineering and of psychiatry and behavioral sciences. "Now, for the first time, we've been able to advance this capability to control multiple individually specified cells at once, and make an animal perceive something specific that in fact is not really there -- and behave accordingly."

The study, to be published online July 18 in Science, holds implications for obtaining a better understanding of natural information processing in the brain, as well as psychiatric disorders such as schizophrenia, and points to the possibility of designing neural prosthetic devices with single-cell resolution.

Deisseroth is the study's senior author. Lead authorship is shared by staff scientists James Marshel, PhD, and Sean Quirin, PhD; graduate student Yoon Seok Kim; and postdoctoral scholar Timothy Machado, PhD.

Using optogenetics

Deisseroth, who is a Howard Hughes Medical Institute investigator and holds the D. H. Chen Professorship, pioneered optogenetics, a technology enabling researchers to stimulate particular neurons in freely moving animals with pulses of light, and to observe the resulting effects on the animals' brain function and behavior.

In the new study, Deisseroth and his colleagues inserted a combination of two genes into large numbers of neurons in the visual cortex of lab mice. One gene encoded a light-sensitive protein that caused the neuron to fire in response to a pulse of laser light of a narrowly defined color -- in this case, in the infrared spectrum. The other gene encoded a fluorescent protein that glowed green whenever the neuron was active.

The scientists created cranial windows in the mice by removing a portion of the animals' skulls to expose part of the visual cortex, which in both mice and humans is responsible for processing information relayed from the retina. The investigators protected this exposed area with a clear glass covering. They could then use a device they developed for the purpose of the study to project holograms -- three-dimensional configurations of targeted photons -- onto, and into, the visual cortex. These photons would land at precise spots along specific neurons. The researchers could monitor the resulting activity of nearly all individual neurons in two distinct layers of the cerebral cortex spanning about 1 square millimeter and containing on the order of several thousand neurons.

With their heads fixed in a comfortable position, the mice were shown random series of horizontal and vertical bars displayed on a screen. The researchers observed and recorded which neurons in the exposed visual cortex were preferentially activated by one or the other orientation. From these results, the scientists were able to identify dispersed populations of individual neurons that were "tuned" to either horizontal or vertical visual displays.

They were then able to "play back" these recordings in the form of holograms that produced spots of infrared light on just neurons that were responsive to horizontal, or to vertical, bars. The resulting downstream neuronal activity, even at locations relatively far from the stimulated neurons, was quite similar to that observed when the natural stimulus -- a black horizontal or vertical bar on a white background -- was displayed on the screen.

The scientists trained the mice to lick the end of a nearby tube for water when they saw a vertical bar but not when they saw a horizontal one or saw neither. Over the course of several days, as the animals' ability to discriminate between horizontal and vertical bars improved, the scientists gradually reduced the black-white contrast to make the task progressively harder. They found that the mice's performance perked up if the scientists supplemented the visual displays with simultaneous optogenetic stimulation: For example, if an animal's performance deteriorated as a result of a lowered contrast, the investigators could boost its discrimination powers by stimulating neurons previously identified as preferentially disposed to fire in response to a horizontal or vertical bar.

This boost occurred only when the optogenetic stimulation was consistent with the visual stimulation -- for example, a vertical bar display plus stimulation of neurons previously identified as likely to fire in response to vertically oriented bars.

Hallucinating mice

Once the mice had become adept at discriminating between horizontal and vertical bars, the scientists were able to induce tube-licking behavior in the mice simply by projecting the "vertical" holographic program onto the mice's visual cortex. But the mice wouldn't lick the tube if the "horizontal" program was projected instead.

"Not only is the animal doing the same thing, but the brain is, too," Deisseroth said. "So we know we're either recreating the natural perception or creating something a whole lot like it."

In their early experiments, the scientists had identified numerous neurons as being tuned to either a horizontal or a vertical orientation, but they hadn't yet directly stimulated each of those particular neurons optogenetically. Once the mice were trained, optogenetic stimulation of small numbers of these neurons was enough to get mice to respond with appropriate licking or nonlicking behavior.

The researchers were surprised to find that optogenetically stimulating about 20 neurons -- or fewer in some cases -- selected only for being responsive to the right orientation, could produce the same neuronal activity and animal behavior that displaying the vertical or horizontal bar did.

"It's quite remarkable how few neurons you need to specifically stimulate in an animal to generate a perception," Deisseroth said.

"A mouse brain has millions of neurons; a human brain has many billions," he said. "If just 20 or so can create a perception, then why are we not hallucinating all the time, due to spurious random activity? Our study shows that the mammalian cortex is somehow poised to be responsive to an amazingly low number of cells without causing spurious perceptions in response to noise."

Forests in Darien, an eastern province of Panama, are crucial for carbon storage, biodiversity conservation and the livelihoods of indigenous groups, yet they are under threat due to illegal logging. Through a participatory forest-carbon monitoring project, scientists from the Smithsonian Tropical Research Institute (STRI), McGill University and the National Research Council of Canada uncovered sources of above-ground biomass (AGB) variation and explored considerations for implementing Reducing Emissions from Deforestation and Forest Degradation (REDD+) in Darien.

"Indigenous authorities were interested in quantifying forest-carbon stocks using field-based measurements to validate the REDD+ potential of their forests and engage in informed discussions with REDD+ proponents in the country," said Javier Mateo-Vega, former research fellow at STRI and main author of the study.

As part of the study, the scientists and a team of trained indigenous technicians analyzed 30 one-hectare plots distributed across a large, mature forest landscape, in undisturbed and disturbed areas. They found that Darien has the highest carbon stocks among nine mature forest sites across the Neotropics, and the second-highest tree species richness among five mature forest sites in the region, supporting the need to protect it in a culturally appropriate way with the region's indigenous peoples.

"I have been working in Darien since 1993 and also perceived these forests as exceptional. It was very exciting when we analyzed the results to see just 'how' exceptional they really are," said Catherine Potvin, research associate at STRI and Canada Research Chair in Climate Change Mitigation and Tropical Forests at McGill University. "Hopefully our results will help give visibility to their global importance for carbon and for biodiversity."

They also discovered that, although half of the plots in the sample had experienced traditional indigenous extractive activities, satellite analyses of vegetation cover did not detect changes in canopy height or noticeable damage to the landscape like agriculture or cattle ranching would. In the field, however, disturbed plots harbored 54% less biomass than intact forests, so their AGB volumes differed vastly from those of undisturbed plots, but their structure and characteristics did not.

This led researchers to ascertain that the main determinant of AGB variation is the level of disturbance in the forest. That is, the amount of organic matter above the ground--in standing trees-- and the amount of carbon it stores, is mainly affected by the selective extraction of large trees rather than by differences across forest types or any other factors.

The study also revealed that even when disturbed forests lost half of their carbon as compared to undisturbed ones, they maintained the same tree species richness. In addition, disturbed forests still maintained a disproportionately high capacity to sequester carbon, suggesting that they should not necessarily be excluded from REDD+ investments given its interest in targeting areas where climate-change mitigation and biodiversity conservation can be achieved simultaneously.

"Decades of efforts to protect Darien's natural and cultural heritage through different protected areas' management categories and land-tenure regimes for indigenous peoples are being stripped away by rampant illegal logging," Mateo-Vega said. "Our study conclusively demonstrates how important these forests are for climate-change mitigation, biodiversity conservation and the well-being of indigenous peoples."

Thursday, July 18 - Alexey Moskalev, Ph.D., Head of the Laboratory of Geroprotective and Radioprotective technologies, and co-authors from the Institute of biology of Komi Science Center of RAS, the Engelgard's Institute of molecular biology of RAS and Moscow Institute of Physics and Technology published a scientific article titled "Transcriptome Analysis of Long-lived Drosophila melanogaster E(z) Mutants Sheds Light on the Molecular Mechanisms of Longevity" in Nature Scientific Reports - the leading international multidisciplinary weekly journal.

Scientists are now closer to understanding how a genetic mutation found in a fruit fly could hold the key to a longer lifespan. Using genome-wide transcriptome analysis, the team noted that lifespan extension and stress resistance in fruit flies -- Drosophila -- carrying the E(z) histone methyltransferase heterozygous mutation, or the E(z) mutation, were correlated with changes in the expression levels of 239 genes. The expression levels of some of the genes were doubled in flies with the E(z) mutation.

According to the results of the study, the mutant flies had a 22 to 23 percent lifespan extension compared to the control group. In addition, these flies were more resistant to hyperthermia, oxidative stress and endoplasmic reticulum stress, which can disrupt processes designed to help cells stay healthy. The mutant flies were also more fertile, the researchers added.

E(z) genes appear connected with gene expression that affects metabolism, such as carbohydrate metabolism, lipid metabolism, drug metabolism and nucleotide metabolism. The expressions that related to aging were involved in pathways related to the immune response, cell cycle and ribosome biogenesis.

"The findings of the conducted research may be a step toward investigating whether the E(z) mutation could play a role in human longevity and have implications for understanding the role of global derepression of chromatin in aging," said Dr. Alexey Moskalev, Ph.D., Head of the Laboratory of Geroprotective and Radioprotective technologies.

The laboratory of geroprotector and radioprotector technologies of the Institute of Biology Komi SC UrB RAS is regularly publishing research papers in peer-reviewed journals. The laboratory's research is aimed at studying the molecular and genetic mechanisms of lifespan regulation, aging process, stress- and radioresistance. The scientific team succeeded in identifying several dozen genes with pro-longevity action. Geroprotective effects of various pharmacological agents, natural compounds, and plant extracts on aging-related signaling pathways, lifespan and physiological functions are being actively studied. Thanks to the members of the laboratory team, data libraries DrugAge and Geroprotectors.org have been created in collaboration with leading institutions of the world. In addition, studies on the influence of factors of different nature, primarily in small doses and concentrations, on lifespan and non-linear effects (such as hormesis and adaptive response) are being carried. All studies are conducted at a high scientific level with the use of modern methods of obtaining data, their statistical and bioinformatic analysis.

A group of scientists led by 2018 Australian of the Year Professor Michelle Simmons have achieved the first two-qubit gate between atom qubits in silicon - a major milestone on the team's quest to build an atom-scale quantum computer. The pivotal piece of research was published today in world-renowned journal Nature.

A two-qubit gate is the central building block of any quantum computer - and the UNSW team's version of it is the fastest that's ever been demonstrated in silicon, completing an operation in 0.8 nanoseconds, which is ~200 times faster than other existing spin-based two-qubit gates.

In the Simmons' group approach, a two-qubit gate is an operation between two electron spins - comparable to the role that classical logic gates play in conventional electronics. For the first time, the team was able to build a two-qubit gate by placing two atom qubits closer together than ever before, and then - in real-time - controllably observing and measuring their spin states.

The team's unique approach to quantum computing requires not only the placement of individual atom qubits in silicon but all the associated circuitry to initialise, control and read-out the qubits at the nanoscale - a concept that requires such exquisite precision it was long thought to be impossible. But with this major milestone, the team is now positioned to translate their technology into scalable processors.

Professor Simmons, Director of the Centre of Excellence for Quantum Computation and Communication Technology (CQC2T) and founder of Silicon Quantum Computing Pty Ltd., says the past decade of previous results perfectly set the team up to shift the boundaries of what's thought to be "humanly possible".

"Atom qubits hold the world record for the longest coherence times of a qubit in silicon with the highest fidelities," she says. "Using our unique fabrication technologies, we have already demonstrated the ability to read and initialise single electron spins on atom qubits in silicon with very high accuracy. We've also demonstrated that our atomic-scale circuitry has the lowest electrical noise of any system yet devised to connect to a semiconductor qubit.

"Optimising every aspect of the device design with atomic precision has now allowed us to build a really fast, highly accurate two-qubit gate, which is the fundamental building block of a scalable, silicon-based quantum computer.

"We've really shown that it is possible to control the world at the atomic scale - and that the benefits of the approach are transformational, including the remarkable speed at which our system operates."

UNSW Science Dean, Professor Emma Johnston AO, says this key paper further shows just how ground-breaking Professor Simmons' research is.

"This was one of Michelle's team's final milestones to demonstrate that they can actually make a quantum computer using atom qubits. Their next major goal is building a 10-qubit quantum integrated circuit - and we hope they reach that within 3-4 years."

Getting up and close with qubits - engineering with a precision of just thousand-millionths of a metre

Using a scanning tunnelling microscope to precision-place and encapsulate phosphorus atoms in silicon, the team first had to work out the optimal distance between two qubits to enable the crucial operation.

"Our fabrication technique allows us to place the qubits exactly where we want them. This allows us to engineer our two-qubit gate to be as fast as possible," says study lead co-author Sam Gorman from CQC2T.

"Not only have we brought the qubits closer together since our last breakthrough, but we have learnt to control every aspect of the device design with sub-nanometer precision to maintain the high fidelities."

Observing and controlling qubit interactions in real-time

The team was then able to measure how the qubits states evolved in real-time. And, most excitingly, the researchers showed how to control the interaction strength between two electrons on the nano-second timescale.

"Importantly, we were able to bring the qubit's electrons closer or further apart, effectively turning on and off the interaction between them, a prerequisite for a quantum gate," says other lead co-author Yu He.

"The tight confinement of the qubit's electrons, unique to our approach, and the inherently low noise in our system enabled us to demonstrate the fastest two qubit gate in silicon to date."

"The quantum gate we demonstrated, the so-called SWAP gate, is also ideally suited to shuttle quantum information between qubits - and, when combined with a single qubit gate, allows you to run any quantum algorithm."

A thing of physical impossibility? Not anymore

Professor Simmons says that this is the culmination of two decades' worth of work.

"This is a massive advance: to be able to control nature at its very smallest level so that we can create interactions between two atoms but also individually talk to each one without disturbing the other is incredible. A lot of people thought this would not be possible," she says.

"The promise has always been that if we could control the qubit world at this scale, they would be fast, and they sure are!"

At a glance:

Over eight years, patients covered under a global budget payment model for doctors and hospitals showed slower spending growth and better quality than comparable populations mostly under the traditional fee-for-service model.

Patients whose providers were paid by the global payment model for eight years spent nearly 12 percent less on medical claims than the comparison population.

These savings on claims were smaller than incentive payments to providers in the first half of the model but exceeded incentive payments during the second half to generate net savings for the program.

Patients in the global payment program received improved quality of care for chronic diseases such as diabetes and high blood pressure and had fewer emergency room visits than peers in comparison states and nationwide.

The study examines what is likely the largest and longest running private-payer contract of a population-based global budget instead of paying fees for each service provided.

One popular idea for lowering the nation's ballooning health care spending is to change the way insurers pay provider organizations for their care. Instead of paying a fee for each service rendered--a model that can encourage the unscrupulous use of more services even when the benefit is dubious--reformers suggest giving clinical practices a global yearly budget to care for a population of patients. The rationale is that operating with a capped budget would incentivize greater use of preventive care and discourage wasteful services.

Evidence from preliminary, and mostly short-term, studies of these so-called "global payment" experiments has been mixed and has offered a limited snapshot on outcomes. The question remained: Could it work over the longer term once the early changes or investments in care delivery had been made?

The likely answer may be yes, according to research published July 18, 2019 in The New England Journal of Medicine, which reveals that one of the largest, oldest private insurance plans to use population-based global budgets achieved sustained success in slowing spending growth while improving the quality of patient care.

Over eight years, average medical spending for patients of an initial cohort of provider groups covered by an alternative, global payment contract with a large commercial insurance provider in Massachusetts saved nearly 12 percent ($461 per member, per year) on medical claims, compared with patients likely in traditional, fee-for-service plans across the northeastern United States. Subsequent provider groups with fewer years in the payment model had comparable or smaller savings on claims.

The study, led by researchers in the Department of Health Care Policy in the Blavatnik Institute at Harvard Medical School, examined changes in spending on medical claims, the volume of services patients used, and the quality of care they received through eight years of the Blue Cross Blue Shield of Massachusetts Alternative Quality Contract (AQC), representing the largest and longest-running global-budget contract offered by a private insurance provider.

"Health care costs are high, and they continue to grow nationwide," said study author Zirui Song, assistant professor of health care policy and of medicine at Harvard Medical School. "The evidence we found suggests that this global payment program has slowed the growth of spending on claims, improved several aspects of quality relative to regional and national averages, and changed some dimensions of provider behavior in a potentially sustainable way."

While incentive payments to providers do offset a significant portion of savings on claims, the latter nevertheless reflects changes in clinical practice, Song said.

"And that is encouraging news," he said.

The analysis found that patients in the global payment model were less likely than those in the comparison group to visit the ER, to receive high-cost specialty drugs and undergo diagnostic imaging procedures, which studies have found are often not optimal and may not provide better outcomes. The study also found that patients in the AQC received improved preventive care and improved management of chronic illnesses such as diabetes and high blood pressure.

"The idea is not to save money by withholding care but to slow the use of questionable, low-value, or unneeded services in favor of high-value care," Song said. "This study shows, that over the longer term, provider organizations can produce meaningful changes in practice and savings for the health care system while improving several aspects of quality of care under incentives that encourage these goals."

The study looked at quality and claims data from 2006 to 2016 from Blue Cross Blue Shield of Massachusetts (BCBS) and from a database of commercial claims and encounters. The longest-term data is from the first cohort of providers, which joined the AQC in 2009. Over eight years (from 2009 to 2016), average annual medical spending on claims for people in the AQC contract grew at a slower rate.

Savings on claims were driven by lower prices in the early years, often due to shifting services from more to less expensive locations or settings, such as switching hospital- or facility-based care to independent- or office-based care. In later years, savings were driven by lower use of services, including laboratory tests, certain imaging tests and emergency room visits. A number of process and outcome quality measures improved relative to regional and national averages.

New provider organizations entered the AQC over the years that the study covered. Savings were generally larger among populations enrolled longer. Patients in organizations that entered the AQC in 2010, 2011 and 2012 had medical claims savings of 12 percent, 7 percent and 2 percent, respectively, by 2016.

The AQC uses what is known as a two-sided risk model: if providers spend less than the target budget, BCBS shares some of the savings with them; if they go over budget, BCBS compensates less than the full amount of the excess so the providers assume some of the cost of overspending. Providers also receive bonuses for meeting quality measures across process, outcome and patient experience domains.

The findings suggest that such a global payment model with both financial rewards and penalties, including robust quality incentives, offer a framework for slowing spending growth without sacrificing quality of care, the researchers said.

URBANA, Ill. - Waterhemp and Palmer amaranth, two aggressive weeds that threaten the food supply in North America, are increasingly hard to kill with commercially available herbicides. A novel approach known as genetic control could one day reduce the need for these chemicals. Now, scientists are one step closer.

In a study published today in Weed Science, researchers from the University of Illinois identified genetic signatures that distinguish male waterhemp and Palmer amaranth plants from females. The discovery is a crucial part of developing a genetic control system for the damaging weeds.

The researchers' goal is to one day introduce genetically modified male plants into a population to mate with wild females. Modified male plants would contain a gene drive, a segment of DNA coding for maleness, which would be passed on to all its offspring, and their offspring, and so on. Ultimately, all plants in a given population would become male, reproduction would cease, and populations would crash.

It's a controversial strategy, but Pat Tranel, the U of I scientist leading the project, says they're still in the very early stages.

"It's important to emphasize that we are not at the point of releasing genetically modified waterhemp and Palmer. We are doing basic research that could inform how we could do that," says Tranel, professor and associate head of the Department of Crop Sciences in the College of Agricultural, Consumer and Environmental Sciences at U of I.

He adds that the team hasn't found the specific gene or genes for maleness in either species. Instead, they identified small genetic sequences associated with a male region, presumably on a particular chromosome. They think the specific gene(s) for maleness lies somewhere within that region.

In the study, the researchers grew 200 plants of each species and each sex, then extracted DNA and determined whether any sequences were unique to a given sex.

"We found sequences present in waterhemp and Palmer males that were not found in females, but no female-specific sequences. Then we took known males from other populations and looked for the sequences - they were there," Tranel says. "Our sequences not only worked, they confirmed males are the heterogametic sex in these plants," Tranel says.

In humans, males have an X and a Y chromosome, and male gametes, sperm, contribute either an X or a Y to the next generation. Females have two X chromosomes, and every egg carries an X. Males are heterogametic; females, homogametic. Similarly, male waterhemp and Palmer amaranth plants produce pollen with either the male-specific Y region or not.

"The fact that males are the heterogametic sex suggests that maleness is dominant. That's good in that it's easier to control the trait (maleness) if the gene for that trait is dominant," Tranel explains. "When we get to the point of identifying the specific genes for maleness, they would be an obvious target for a gene drive where you could spread that maleness gene in the population."

In the meantime, however, having a set of genetic sequences that can accurately identify males before flowering could help the researchers better understand the biology of the plants and their response to the environment. For example, Tranel says the discovery could help determine if the weeds are able to switch sexes under certain conditions or if one sex is more sensitive to herbicides. Both concepts have been proposed by previous research or anecdotal reports.

In addition to pursuing these basic questions, Tranel's team is now working to find the needle in the haystack: the maleness gene within the male region. When they find it, it will take time before genetic control of waterhemp and Palmer amaranth could become a reality. And even then, Tranel says it will still be important to use all the tools in the weed management toolbox.

"I'd never see this as replacing all our other strategies," he says. "But it's super cool to imagine this as part of the solution."

Most Americans believe science and religion are incompatible, but a recent study suggests that scientific engagement can actually promote belief in God.

Researchers from the Arizona State University Department of Psychology found that scientific information can create a feeling of awe, which leads to belief in more abstract views of God. The work will be published in the September 2019 issue of the Journal of Experimental Social Psychology and is now available online.

"There are many ways of thinking about God. Some see God in DNA, some think of God as the universe, and others think of God in Biblical, personified terms," said Kathryn Johnson, associate research professor at ASU and lead author on the study. "We wanted to know if scientific engagement influenced beliefs about the existence or nature of God."

Though science is often thought of in terms of data and experiments, ASU psychology graduate student Jordan Moon, who was a coauthor on the paper, said science might be more to some people. To test how people connect with science and the impact it had on their beliefs about God, the researchers looked at two types of scientific engagement: logical thinking or experiencing the feeling of awe.

The team first surveyed participants about how interested they were in science, how committed they were to logical thinking and how often they felt awe. Reporting a commitment to logic was associated with unbelief. The participants who reported both a strong commitment to logic and having experienced awe, or a feeling of overwhelming wonder that often leads to open-mindedness, were more likely to report believing in God. The most common description of God given by those participants was not what is commonly found in houses of worship: They reported believing in an abstract God described as mystical or limitless.

"When people are awed by the complexity of life or the vastness of the universe, they were more inclined to think in more spiritual ways," Johnson said. "The feeling of awe might make people more open to other ways of conceptualizing God."

In another experiment, the research team had the participants engage with science by watching videos. While a lecture about quantum physics led to unbelief or agnosticism, watching a music video about how atoms are both particles and waves led people to report feeling awe. Those who felt awe also were more likely to believe in an abstract God.

"A lot of people think science and religion do not go together, but they are thinking about science in too simplistic a way and religion in too simplistic a way," said Adam Cohen, professor of psychology and senior author on the paper. "Science is big enough to accommodate religion, and religion is big enough to accommodate science."

Cohen added that the work could lead to broader views of both science and religion.

DGIST announced on Tuesday, July 16 that Senior Researcher Dae-gun Oh's team in the Collaborative Robots Research Center developed a radar system that can detect subminiature drones that are 3km away. This research is expected to make huge contributions to strengthening domestic industries and defense capabilities by securing a world-class radar sensing technology.

As a result of discovering a North Korean drone in Paju in March 2014, South Korea's Ministry of National Defense has adopted a drone detection radar based on an overseas technology. Since last year, the ministry has devoted itself into building a combat system using drones and training specialized personnel by forming a drone unit to strengthen its defense capability. The necessity of enemy surveillance reconnaissance and the early detection of offensive drones has increased in Korea.

Due to the lack of radar detection technology, however, South Korea is using many radar systems from abroad such as drone detection radars from RADA in Israel and Blighter in the U.K. RADA especially owns a superior radar technology performance that can detect drones that are a maximum of 3km away.

Since 2014, DGIST Senior researcher Daegun Oh's team has continuously been working on R&D of a drone detection radar system based on a super-resolution algorithm using only Korean technology and developed Korea's first radar system that can detect drones 200m away for the first time in 2016. Through continuous research, the team successfully developed a world-class radar system that can detect subminiature phantom drones flying in the sky over 3km.

The research team designed the drone detection radar system to operate between 12GHz and 18GHz, and applied super-resolution radar signal processing technology to locate drones accurately by applying an AESA radar1 technology to increase the maximum detection distance of radar. Furthermore, the radar system can identify and detect drones more clearly in real-time by integrating 'GANs (Generative Adversarial Networks'2 -based drone cognition technology, which has been drawing attention as next generation deep learning algorithm.

What is noteworthy is that hardware components such as the transmissio, transmission antenna, receiving unit, receiving antenna, and signal processing platform inside the radar detection system were developed 100% jointly with Korean small and medium-sized companies, which can help create high-added values of regional industries.

Senior researcher Daegun Oh's team in the DGIST Collaborative Robots Research Center said "This research achievement is a result of cooperation with Korean companies to develop radar hardware and our focus on the development of a unique radar signal processing algorithm for detection, tracking, and identification of drones. We will strive harder to enhance the reputation of domestic radar technologies in the global market by changing the market spectrum led by overseas companies." The research team is currently discussing the issue of drone detection radar technology transfer to Korean and overseas defense industries.

The AI radar identification technology in this research achievement was published on the world-class radar journal IEEE Geoscience and Remote Sensing Letters on June 18. Also, papers on the element technology of drone have also been published on Microwave and Optical Technology Letters, IEEE Sensors, IEEE Transactions on Aerospace and Electronics Systems, MDPI Sensors, etc.

Bacteria do not simply perish in hunger phases fortuitously; rather, the surrounding cells have a say as well. A research team from the Technical University of Munich (TUM) has now discovered that two factors, above all, decide over life and death: the energy required to continue living and the efficiency with which surviving cells can recycle biomass from dead cells.

The survival and growth of cells are central factors in biological systems. Scientists such as Ulrich Gerland, Professor for Physics of Complex Biosystems at the TUM, are therefore trying to understand how the molecular components interact to maintain the viability of a group of cells in stress situations.

The team led by Ulrich Gerland has now succeeded in identifying two crucial factors for the survival of a bacterium: the basic energy consumption of a cell and the quantity of energy that the surviving cells can gain per neighboring dead cell, measuring the biomass recycling efficiency.

Nutrients from neighboring cell cadavers

The researchers emulated an emergency situation in cells of the bacterium Escherichia Coli in which the bacteria were lacking sugar and other carbohydrates. The bacteria therefore had neither energy nor building materials available.

As the first cells died, the surviving cells tried to gain nutrients from the surrounding cell cadavers. The higher the energy turnover of a certain enzyme, the greater was the rate of mortality. The more they were able to recycle from dead cells, the higher was the rate of survival.

"Our findings make it possible to quantitatively determine the contributions of individual molecular components to the survival of bacterial cells, for the first time," says Gerland.

Decay of viability as a collective phenomenon

Overall, there was an exponential decrease of surviving cells with time. In principle, such a development can be explained with the random perishing of individual cells, just like in radioactive decay which also has an exponential kinetics.

But the interrelationships are more complex, as the researchers found out when they changed experimental conditions. Decay in bacterial colonies is a collective phenomenon. The surrounding bacterial cells therefore co-determine whether a cell in their midst perishes or survives.

Mathematical analysis of survival

Changes to the mortality rate can arise from a wealth of genetic or ecological perturbations which influence the survival of bacteria. The balance which emerges is therefore different for each bacterium and each environmental condition.

In order to understand the dynamics, the researchers modelled the overall system of surviving bacteria mathematically. Then, they used this relationship to determine molecular contributions to the survival of cells.

Depending on the cell type, important molecular factors for the survival of cells can be identified, and this facilitates the discovery of enzymes or other proteins that determine the rate of survival.

"Our aim is to understand, systematically and quantitatively, how bacteria manage to survive in so many environmental conditions," says Gerland. "It is the search for the physiology of survival."

BOSTON - In metastasis, cancer cells break away from the original tumor and take root in another region of the body by entering the blood stream. In order to spread, metastatic cells cross over the endothelium - a barrier of endothelial cells lining the circulatory system that controls the passing of materials into and out of the blood stream - a behavior not as easily accomplished by non-metastatic cells.

In a study published in Scientific Reports, first author Yamicia D. Connor, MD, PhD, a resident in the Department of Obstetrics and Gynecology at Beth Israel Deaconess Medical Center (BIDMC), and colleagues, reveal that unlike non-metastatic cells, breast metastatic cells have the ability to change shape, flattening to more effectively cross the endothelium and into the blood stream. In addition to demonstrating the transformation, the team developed a mathematical model to quantitatively illustrate this interaction between the metastatic and endothelial cells that can be easily modified for studying similar cellular systems.

"Our data show that breast metastatic cells are not only able to find blood vessels more effectively, but they also are able to change their shape to help facilitate crossing into the blood stream, which is a critical step in the spread of cancer," said Connor. "The study demonstrates how mathematical models can be paired with biological systems to provide and quantify important insights in cellular biology and potentially test drug targets."

Using the same mathematical model, researchers can investigate whether this behavior is limited to breast cancer or if it applies to other metastatic diseases. In a separate study, Connor's team is exploring if ovarian cancer cells may similarly interact with the endothelium as the breast cancer cells.

"These findings provide a framework for examining a tumor's metastatic potential in a 3D model system," said Toni Golen, MD, Vice Chair of the Department of Obstetrics and Gynecology at BIDMC, who was not involved in the research. "This may serve as the basis for future research to investigate whether quantifying physical interactions between metastatic cells and other cell types can provide insight into the mechanism of metastatic disease that can be used to guide treatment decisions."

July 17, 2019 (Arlington, VA) -- Below is a summary of a study published online today in Infection Control and Hospital Epidemiology. This article will be freely available for a limited time. SHEA members have full access to all ICHE articles through the online portal.

Title: "Current infection prevention and antibiotic stewardship program practices: A survey of the SHEA Research Network."

Summary: This study was conducted within the SHEA Research Network, a large consortium of healthcare facilities dedicated to conducting high-quality studies related to infection prevention and control and antibiotic stewardship. The survey demonstrates that surveillance for antibiotic-resistant bacteria continues to be a core focus for healthcare facilities. As compared to a similar 2013 survey, active surveillance for methicillin-resistant Staphylococcus aureus (MRSA) has declined, while active surveillance for carbapenem-resistant Enterobacteriaceae (CRE) is now performed in half of centers. This work further highlights the growth in financially supported antibiotic stewardship programs over the past 5 years, as well as frequent use of rapid molecular diagnostic tests to expedite appropriate antibiotic therapy for patients with bloodstream infections. Finally, while half of facilities anticipated increased responsibilities for infection control and antibiotic stewardship staff, the minority anticipated increases in funding for this important work.

Highlights:

- Antimicrobial stewardship programs were present in 95 facilities in 2018, an increase from 85 percent in 2013.

- There's been a shift in focus toward active surveillance for MDR-GN organisms, with fewer facilities reporting active MRSA surveillance, which may reflect 2015 CDC recommendations

- Financial support for physician stewardship medical directors increased to 78 percent in 2018 from 52 percent in 2013.

- Monitoring of environmental cleaning effectiveness was more frequent in 2018, when it was performed in 98% of facilities compared to 80 % in 2013.

- Ultraviolet light and hydrogen peroxide mist were used for environmental cleaning in 37 and 16 percent of facilities, respectively, in 2018 and 2013.

A study performed at the Institute for Research in Biomedicine (IRB Barcelona) and published in the journal Nature Communications demonstrates that inhibition of the p38 protein boosts the formation of blood vessels in human and mice colon cancers. Known as angiogenesis, this process is critical in fuelling cancer cells, allowing them to grow and to eventually develop metastases.

The team led by Ángel R. Nebreda, head of the Signalling and Cell Cycle Laboratory at IRB Barcelona, has shown that the activity of p38 is important in mesenchymal stem cells (MSCs), which show high plasticity and can localize around blood vessels. These cells participate in various processes, such as tumour development, and this study unveils their relevance in the regulation of angiogenesis.

The activity of p38 in cancer cells had already been described. However, until now, little was known about the role of this protein in MSCs and even less about its involvement in angiogenesis.

The objective of this study was to examine the role of p38 in new blood vessel formation during tumorigenesis, in particular considering the contribution of MSCs.

In this regard, as explained by Nebreda, ICREA researcher at IRB Barcelona, the study demonstrates that "p38 represses angiogenesis by exerting its action specifically in MSCs. Using genetic mouse models, we show that the inhibition of p38 stimulates the formation of new blood vessels both in tumours and during the repair of damaged tissue".

The conclusions of this study shed light on the mechanisms that regulate blood vessel formation and may have implications for the optimisation of chemotherapy-based cancer treatments, as well as for the treatment of diseases involving compromised angiogenesis.

"We hope that the biological knowledge that our work has generated can contribute to the development of more efficient therapies," concludes Raquel Batlle, postdoctoral fellow at IRB Barcelona and first author of the study.

Osaka, Japan - While pinning down a single oxygen atom sounds difficult, trying to then manipulate electrons associated with that single atom to alter its charge sounds downright impossible. However, for the first time, this achievement has been reported by an international research team led by Osaka University.

Along with collaborators from Slovakia and the United Kingdom, graduate student Yuuki Adachi from Osaka University's Department of Applied Physics has recently published this research in ACS Nano.

Oxygen is one of the most abundant elements on Earth. Usually found in its diatomic form, O2, oxygen is highly reactive and doesn't hang around long in a gaseous state. The ground state, or least reactive form of oxygen, is referred to as triplet oxygen because it has three possible arrangements of electron spins. However, singlet oxygen, with its one possible spin arrangement, is more reactive and plays a major role in a diverse range of chemical reactions, ranging from green fuel production to photodynamic cancer treatments.

Unsurprisingly then, there is significant interest in controlling the formation and activation of molecular oxygen.

"We used Kelvin probe force spectroscopy to examine the charge states of oxygen atoms attached to a titanium dioxide rutile surface, and to then manipulate the charge through the transfer of individual electrons to and from pairs of oxygen atoms," explains Adachi. "We identified three different charge states amongst the pairs: O-/O-, O2-/O2-, and O-/O2-. Depending on the applied voltage and where we positioned the tip of the probe relative to the atoms, we could then reversibly switch the charge between the O- and O2- states."

The team then showed that they could use the same method to induce controlled, reversible bond formation between two adjacent oxygen atoms, forming molecular oxygen (O2).

Interestingly, they also found that the charge state could be controlled remotely by locating the tip elsewhere on the rutile surface. Electrons were transferred to the oxygen atoms via surface polarons, a phenomenon where electrons can travel through a crystal lattice.

"This level of control over the charge state of oxygen atoms has not previously been possible," says corresponding author of the study Associate Professor Yan Jun Li. "Our work provides a novel method to examine transition-metal-oxide-based catalytic reactions, and can likely be applied to other atoms, and perhaps other surfaces, where controlled chemical reactions initiated by charge manipulation are performed."

Military deployments to austere environments - whether humanitarian missions or combat operations - involve extensive logistical planning, which is often complicated by unforeseen events. Researchers at North Carolina State University have now created a model aimed at helping military leaders better account for logistical risk and uncertainty during operational planning and execution.

"Every branch of the military now uses an enterprise resource planning (ERP) system that handles everything from requisitions to shipment of supplies to inventory tracking," says Brandon McConnell, corresponding author of a paper on the new model and a research assistant professor in NC State's Edward P. Fitts Department of Industrial and Systems Engineering. "These ERP systems make it possible to create computational models that can be used to identify the most efficient means of meeting the military's logistical needs.

"These models would be particularly valuable during expeditionary operations, in which the military is seeking to establish its presence - and its supply chain - in an environment that is subject to a fair amount of uncertainty.

"The model that we've developed can not only facilitate the military's ability to efficiently determine what will be needed where, but can also assess risk in near real time in order to account for uncertainty," says McConnell, a former infantry captain in the U.S. Army who served two tours in Iraq.

The new model, called the Military Logistics Network Planning System (MLNPS), draws on three sources of information. First is logistical data from the ERP system. Second is operational data, such as an operation's mission, organization and timeline. Third is data on "mission specific demand," meaning logistical requirements that are particular to a given mission and its environment. For example, a combat operation being conducted in a cold, damp environment would have different requirements than a humanitarian mission being conducted in a hot, dry environment.

The MLNPS also uses two factors to assess risk and determine how risk might affect military capacities. The first factor is the likelihood that an event will happen; the second factor is what the consequences of that event will be. For example, if the likelihood of two events is identical, the model would give more weight to the event that could have a greater adverse impact on military personnel and mission performance.

"The MLNPS uses all of the available data, accounts for risk, then forecasts what the logistical outcomes will look like in reality," McConnell says. "The MLNPS can be used as a decision planning aid, allowing leaders to test-drive plans in order to identify courses of action that will best support carrying out an operation."

The MLNPS could also be used while an operation is being executed, as part of contingent logistical planning efforts that take place as circumstances change on the ground.

"Right now, the MLNPS is a robust proof-of-concept prototype, designed to demonstrate the potential value of powerful computational tools that can make use of ERP systems," McConnell says. "Existing logistical tools are both valuable and powerful. However, I'm not aware of any other methods that make use of ERP data and are also fast enough for operational use when time is of the essence."

"This research lays the mathematical and operational foundation for construction of a network-based model that captures routing alternatives and characterizes solutions for capacity planning and resiliency analysis in near-real time," says Joseph Myers, Army Research Office mathematical sciences division chief at the Combat Capabilities Development Command's Army Research Laboratory. "This project will provide military logistics planners with capabilities that are currently lacking in prevalent logistics planning tools."

The good news is that adolescent "sexting" is not at epidemic levels as reported in some media headlines. The bad news is that it also has not decreased despite preventive efforts by educators and others. Most commonly, the term sexting has been used to describe incidents where teenagers take nude or semi-nude photos or videos of themselves and exchange that content via text or private social media messages. While intended to be shared with trusted romantic partners, these images also can find their way into the hands of others.

While national studies have contributed to the understanding of sexting behavior among minors, the prevalence estimates are dated (prior to January 2011), and therefore, little is known about its frequency and scope on a national level in recent years.

A new study by researchers at Florida Atlantic University and the University of Wisconsin-Eau Claire is providing a much-needed update to what is currently known about the nature and extent of sexting among youth today.

The study, published in the journal Archives of Sexual Behavior, examined prevalence rates for sending and receiving sexually explicit images or video among a nationally-representative sample of 5,593 American middle and high school students (ages 12 to 17). Researchers focused only on explicit images and videos (as some previous studies have conflated the picture by also including explicit texts) in order to isolate those experiences that have the greatest potential for problematic outcomes.

Results show that across all sociodemographic variables explored, the vast majority of students were not participating in sexting. Approximately 14 percent of middle and high school students had received a sexually explicit image from a boyfriend or girlfriend, while 13.6 percent said they received such an image from someone who was not a current romantic partner. About 11 percent of students reported sending a sext to a boyfriend or girlfriend.

Interestingly, most of the students who were asked by a current boyfriend or girlfriend to send a sext complied (63.9 percent). Among those students who were asked to send a sext by someone who was not a current romantic partner, only 43 percent complied.

Males were significantly more likely to have sent and received a sext from a current romantic partner. However, males and females were equally likely to receive them from someone who was not a current boyfriend or girlfriend. Female students were more likely to have been asked to send a sext by someone who was not a current romantic partner (14.3 percent), but only 34.1 percent complied.

Among the different racial groups examined, no statistically significant differences emerged with regard to sexting participation. As expected, older youth were more likely to both send and receive sexts. Students who identified as non-heterosexual were significantly more likely to be involved in sexting in all its forms.

With regard to frequency, about one-third of the students who sent or received explicit messages did so only once. Most commonly, students engaged in these behaviors "a few times." Fewer than 2 percent of all students said they had sent a sext "many times," while 2.6 percent said they had received sexts "many times."

Overall, about 4 percent of students said they shared an explicit image sent to them with another person without their permission, and the about same number believed an image of them was shared with others without permission. This, of course, can lead to instances of "sextortion," which the authors also have studied. Males were more likely to have shared an image and were more likely to believe an image they sent had been shared with others without permission. Non-heterosexual students were approximately twice as likely to have shared an image with others and to believe their image had been shared with others without permission. It also appears that 15-year-olds were the most likely to have shared a sext and to believe a sext of them was shared without permission.

"Findings from our study provide a very important message for youth who may believe media headlines that suggest sexting is more widespread than it actually is," said Sameer Hinduja, Ph.D., a professor in the School of Criminology and Criminal Justice within FAU's College for Design and Social Inquiry and co-director of the Cyberbullying Research Center, who co-authored the study with Justin Patchin, Ph.D., a professor of criminal justice at the University of Wisconsin-Eau Claire and co-director of the Cyberbullying Research Center. "Showing adolescents clear evidence that a relatively small proportion of teens engage in sexting could actually result in decreased overall participation since it underscores that it is not as normal, commonplace, or widespread as they might believe."