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What The Study Did: This study of 84 young drivers looked at the association between motor vehicle crashes and differences in the development of working memory, which is critical to awareness of hazards while driving.

Authors: Elizabeth A. Walshe, Ph.D., of the University of Pennsylvania in Philadelphia, is the corresponding author.

(doi:10.1001/jamanetworkopen.2019.11421)

Editor's Note: The article includes conflict of interest and funding/support disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

The sea-ice extent in the Arctic is nearing its annual minimum at the end of the melt season in September. Only circa 3.9 million square kilometres of the Arctic Ocean are covered by sea ice any more, according to researchers from the Alfred Wegener Institute and the University of Bremen. This is only the second time that the annual minimum has dropped below four million square kilometres since satellite measurements began in 1979.

Until mid-August, it looked as though a notable record would be reached: the area of the Arctic Ocean covered by ice (defined as the area with a sea-ice concentration of more than 15 percent) from late March to early August was the smallest measured by satellites since 1979. "Our satellite data show that between March and April 2019, there was an unusually large decrease in the ice extent, from which the Arctic sea ice was unable to recover," explain Professor Christian Haas, a geophysicist and head of the Sea Ice section at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) and Dr Gunnar Spreen from the University of Bremen's Institute for Environmental Physics. Since the second half of August, however, the seasonal reduction has slowed down, overlaid by short-term fluctuations. The lowest value so far for 2019 was 3.82 million square kilometres, observed on 3 September. This means that this year, the September average could be below 4 million square kilometres for only the second time.

But in the coming weeks, the ice could retreat further: even though in early fall air temperatures in the Arctic have now fallen below freezing, the heat stored in the water can continue to melt the underside of the ice for a few more weeks. However, if it becomes extremely cold in the Arctic in the days ahead, the ice cover can already increase again. In October, the scientists will analyse the data for the whole of September, and will then be able to make a final assessment of the sea-ice minimum in 2019. It appears unlikely that this year we will see a new absolute record, below the sea-ice extent of 3.4 million square kilometres observed in 2012. "Record or not, this year confirms the continued long-term reduction of Arctic sea ice as a result of climate change, making it ever more likely that in a few decades the Arctic will be ice free in summer. This will mean drastic changes in the Arctic, with consequences for the climate and ecosystems, as well as for people, including us in Europe," says Christian Haas.

Scientists at the Alfred Wegener Institute and the Institute for Environmental Physics at the University of Bremen are together analysing the complete satellite data on the ice concentration, extent, and thickness, as well as atmospheric measurements. The website https://www.meereisportal.de/en/ , for example, publishes daily updated ice maps and provides detailed summaries of the sea-ice developments. Ice extent estimates from other institutions (e.g. NSIDC or OSI-SAF) can provide slightly different results. Currently, for 2019 they predict the third-lowest ice extent. "These slight differences are due to the higher resolution of our data and the slightly different methods used to calculate the ice concentration. They show the uncertainties that even the most modern satellite observations can have. Data from the MOSAiC expedition will help to reduce these uncertainties," explains Dr Gunnar Spreen from the University of Bremen's Institute for Environmental Physics.

The researchers are currently particularly interested in the northern Laptev Sea: on 20 September, the research icebreaker Polarstern will set sail from Tromsø, in Norway, for the start of the MOSAiC expedition. In the northern Laptev Sea they will search for a suitable ice floe to moor the Polarstern to, in order to drift, icebound, through the Central Arctic for an entire year. "We're following the ice situation very closely and have developed a series of new data products to offer the best-possible, detailed insights into the current conditions," reports Christian Haas. "In the Laptev Sea, the ice situation is similar to previous years with an Arctic-wide low ice extent. This means that it will be relatively easy for us to reach our research area, at a latitude of 85 degrees north. But being so close to the ice edge will make it difficult to find a suitable ice floe that is large enough and thick enough to set up our ice camp. Our computer models show that the ice south of 88 degrees north is less than 80 centimetres thick, which is less than the 1.2 metres we'd ideally like to have to safely set up our measuring stations. We may have to travel farther north than planned to find the right conditions," expects Christian Haas, who will lead the second leg of the MOSAiC expedition from mid-December.

UNIVERSITY PARK, Pa. -- Students in Pennsylvania school districts that participated in Communities that Care (CTC) coalitions were significantly less likely to use alcohol or marijuana, or to engage in delinquent behavior than those in non-CTC districts, according to a recent study published in Prevention Science.

Penn State researchers analyzed data from 388 Pennsylvania school districts collected during at least one year from 2001-11, from the Pennsylvania Youth Survey (PAYS), a bi-annual survey of youth in sixth, eighth, 10th and 12th grades.

Based upon self-reports, students in the CTC school districts that used at least one evidence-based program were less likely to engage in marijuana use by 22%, cigarette use by 17%, alcohol consumption by 15%, were 18% less likely to be high or drunk in school, and 12% less likely to be arrested.

More than 500 communities throughout the U.S. use the CTC model, which involves a five-phase change process with the goal of promoting healthy youth development and reducing problem behaviors. Coalitions comprised of community stakeholders receive training in prevention science methods and data-based decision making, and then select and implement programs that have been shown in prior research to significantly improve the lives of children and families involved.

The study, funded by the National Institute on Drug Abuse, is the largest to-date to examine the effectiveness of Pennsylvania CTC coalitions.

"There is a real need for thoughtful, developmentally-sensitive, and coordinated prevention programming across K-12 schools in Pennsylvania, with a focus on the development of early social-emotional competencies and protective developmental assets that all children need to succeed," said Jennifer Frank, Penn State assistant professor of education and principal investigator on the study.

"It's really about the power of taking a systematic and collaborative approach to prevention and a sustained commitment," added Sarah Chilenski, senior research associate for the Edna Bennett Pierce Prevention Research Center and the study's lead author. "I'd like to see community monitoring systems like the PAYS integrated in public and private schools in every state and district, coupled with consistent funding for programs that have been proven effective."

Geoff Kolchin, PAYS project leader for the Commonwealth of Pennsylvania, noted that PAYS data can be instrumental in helping schools select appropriate evidence-based programming to address the risks faced by their youth based on responses from those youth themselves. PAYS is offered to all schools and school districts in Pennsylvania at no cost through a partnership between the Pennsylvania Commission on Crime and Delinquency, the Pennsylvania Department of Drug and Alcohol Programs, and the Pennsylvania Department of Education.

Since Friedrich Wohler synthesized urea (by accident) back in 1828, chemical synthesis - and organic synthesis for that - has been a driving force in pharmaceutical innovation. Improving the lives of people worldwide, the medicines available nowadays are only possible thanks to the continuous advancement of synthetic chemistry, allowing scientists to design and build new molecules. Now, Marcos G. Suero and his research group at the Institute of Chemical Research of Catalonia (ICIQ) present a new reaction that allows for the edition of organic molecule's skeletons, opening up new avenues of research.

Editing skeletons

In a paper published in the Journal of the American Chemical Society, the Suero research team presents a new reaction able to edit the skeletons of organic molecules by breaking strong C-C double bonds and inserting a carbon atom through a catalytic process. The ICIQ researchers present the first catalytic generation of Rh-carbynoids, which emulate the carbene/carbocation behavior of a monovalent cationic carbyne. The catalytic generation of Rh-carbynoids represents a new platform for carbyne transfer that enables skeletal remodelling, and circumvents a long-standing challenge in the catalytic generation of metal-carbynes.

Aside from inserting a new monovalent carbon atom, the reaction also introduces extra complexity in the molecule: a single C-C bond and a double C-C bond are created together with a chiral center at one of the C atoms with the cleaved double bond. The skeletal editing will allow building complex architectures, thus expanding the synthetic possibilities of creating new materials or medicines.

A team of engineers at UC San Diego has discovered a method that could make materials more resilient against massive shocks such as earthquakes or explosions. Undergraduate researchers in the structural engineering lab of Professor Veronica Eliasson used a shock tube to generate powerful explosions--at Mach 1.2 to be exact, meaning faster than the speed of sound. They then used an ultra high-speed camera to capture and analyze how materials with certain patterns fared.

Previous research from Eliasson's lab had shown that obstacles laid out in a logarithmic spiral--picture a Nautilus shell spiraling around and around--were better able to diminish the energy of a shock wave and reduce overall damage than when arranged in other patterns. The researchers took that a step further, testing whether cutting three grooves into each side of the obstacle materials would be an even better attenuator of the shock when compared with similar obstacles laid out in a logarithmic spiral but with no grooves.

They found that these grooves did diminish the impacts of what's called the reflected shock wave--once the initial wave has hit the spiral of obstacles and bounced back. Results were inconclusive for the initial transmitted shock wave. The researchers reported their findings in a recent issue of the journal Multiscale and Multidisciplinary Modeling, Experiments and Design.

"This research can be used in military applications and civil applications too, to design materials and buildings to better withstand high-intensity blasts," said Christina Scafidi, one of the authors of the paper, who graduated in 2019 with a degree in structural engineering.

"The coal industry has had many fatal accidents and we believe this research presents a strong case for protecting the workers from blast waves that can easily propagate throughout an entire coal mine," added Alexander Ivanov, a recent aerospace engineering graduate and co-author of the paper. "If the entire wall of the coal mine could be lined with these solid geometric obstacles, it could provide a cheap way to protect all of the workers in the mine."

The first-ever comet from beyond our Solar System has been successfully imaged by the Gemini Observatory in multiple colors. The image of the newly discovered object, denoted C/2019 Q4 (Borisov), was obtained on the night of 9-10 September using the Gemini Multi-Object Spectrograph on the Gemini North Telescope on Hawaii's Maunakea.

"This image was possible because of Gemini's ability to rapidly adjust observations and observe objects like this, which have very short windows of visibility," said Andrew Stephens of Gemini Observatory who coordinated the observations. "However, we really had to scramble for this one since we got the final details at 3:00 am and were observing it by 4:45!"

The image shows a very pronounced tail, indicative of outgassing, which is what defines a cometary object. This is the first time an interstellar visitor to our Solar System has clearly shown a tail due to outgassing. The only other interstellar visitor studied in our Solar System was 'Oumuamua which was a very elongated asteroid-like object with no obvious outgassing.

The Gemini observations used for this image were obtained in two color bands (filters) and combined to produce a color image. The observations were obtained as part of a target of opportunity program led by Piotr Guzik and Michal Drahus at the Jagiellonian University in Krakow (Poland). The research team has submitted a paper for publication.

C/2019 Q4 is currently close to the apparent position of the Sun in our sky and is consequently difficult to observe due to the glow of twilight. The comet's hyperbolic path, which is evidence of its origin beyond our Solar System, will bring it to more favorable observing conditions over the next few months.

C/2019 Q4 was discovered by Russian amateur astronomer Gennady Borisov on 30 August, 2019.

NASA-NOAA's Suomi NPP satellite passed over the Eastern Pacific Ocean in the early hours of Sept. 12 and grabbed a nighttime look at Tropical Storm Kiko.

Kiko developed on Sept. 11 as Tropical Depression 13E and strengthened into a tropical storm by 5 p.m. EDT. Once it attained tropical storm status, it was named Kiko.

On Sept. 12 at 4:54 a.m. EDT (0854 UTC), the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA's Suomi NPP provided an infrared image of the strengthening storm. At the time of the overpass the National Hurricane Center (NHC) noted, "There's a small patch of convection (rising air that formed thunderstorms) near the estimated center, with another larger cluster much farther south. For the most part, however, the circulation consists of a broken low- and mid-level cloud deck with a few embedded showers." The Suomi NPP image also showed a larger band of thunderstorms had developed north of center.

At 11 a.m. EDT (1500 UTC), the center of Tropical Storm Kiko was located near latitude 16.9 degrees north and longitude 114.4 degrees west. Kiko is far from land and about 505 miles (815 km) southwest of the southern tip of Baja California, Mexico. Kiko was moving toward the west-northwest near 10 mph (17 kph) and this motion is expected to continue through Monday. Maximum sustained winds are near 40 mph (65 km/h) with higher gusts. Estimated minimum central pressure is 1004 millibars.

Some strengthening is forecast during the next 48 hours, and Kiko is expected to approach hurricane strength later this weekend.

For updated forecasts, visit: http://www.nhc.noaa.gov

Wake Forest Institute for Regenerative Medicine scientists have fine-tuned their delivery system to deliver a DNA editing tool to alter DNA sequences and modify gene function. The improved "hit and run" system works faster and is more efficient.

"With this new method we are able to package together in one lentiviral capsid both essential components (Cas9 protein and guide RNA) for the CRISPR mediated gene editing," said Baisong Lu, Ph.D, assistant professor of regenerative medicine at WFIRM and one of the lead authors of the paper. "Previously, the two components had to be delivered separately which was not as convenient."

CRISPR (clustered regularly interspaced short palindromic repeats) technology is used to alter DNA sequences and modify gene function. CRISPR/Cas9 is an enzyme that is used like a pair of scissors to cut two strands of DNA at a specific location to add, remove or repair bits of DNA. But CRISPR/Cas9 is not 100 percent accurate and could potentially cut unexpected locations, causing unwanted results.

Now the WFIRM team can package the two components -- Cas9 protein (the enzyme) and the guide RNA--as ribonucleoproteins inside the lentiviral capsid, creating a lentiviral capsid-based bionanoparticle system for delivering CRISPR/Cas9. Lentiviral vector is a widely used gene delivery vehicle in research labs and is already widely used for delivering the CRISPR/Cas9 machinery for efficient genome editing. However, using lentiviral vector to deliver CRISPR/Cas9 will result in long-term expression of the endonuclease, which is undesired for safety reasons. The new system offers the delivery efficiency of conventional lentiviral vectors, but enables transient Cas9 expression. Thus, the new CRISPR/Cas9 delivery system is more efficient and safer.

The research has led the team to hypothesize that a "similar strategy should be translatable to other editor proteins for gene disruption," said Anthony Atala, M.D., director of WFIRM and a co-author of the paper. "We may be able to utilize this to package and deliver other RNPs into mammalian cells, which has been difficult to achieve so far."

The research is part of an ongoing effort to improve in vivo gene editing efficiency which will be useful in research and clinical applications by improving safety and avoiding possible immune responses.

As the Bahamas continue to recover from Category 5 hurricane Dorian, a new developing tropical cyclone is bringing additional rainfall to an already soaked area.

The Global Precipitation Measurement mission or GPM core satellite provided a look at those rainfall rates occurring in Potential Tropical Cyclone Nine, located over the Bahamas.

Potential Tropical Cyclone 9 developed around 5 p.m. EDT on Thursday, Sept. 12. At 11 a.m. EDT on Sept. 13, the depression triggered watches and warnings from NOAA's National Hurricane Center. A Tropical Storm Warning is in effect for the northwestern Bahamas excluding Andros Island and a Tropical Storm Watch is in effect from Jupiter Inlet to the Flagler-Volusia County line, Fla.

Watches and warnings are already in effect. A Tropical Storm Warning is in effect for the northwestern Bahamas excluding Andros Island and a Tropical Storm Watch is in effect from Jupiter Inlet to Flagler-Volusia County line, Fla.

The GPM or Global Precipitation Measurement mission's core satellite passed over Tropical Depression 9 on Sept. 13 at 2:26 a.m. EDT (0726 UTC). GPM found the heaviest rainfall northwest of the center where it was falling at a rate of over 40 mm (about 1.6 inch) per hour. GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency, JAXA.

NOAA's National Hurricane Center noted at 2 p.m. EDT (1800 UTC), the disturbance was centered near latitude 25.4 degrees north and longitude 74.2 degrees west. The system is expected to resume a slow motion toward the northwest and north-northwest later in the day. Maximum sustained winds are near 30 mph (45 kph) with higher gusts. The disturbance is forecast to become a tropical depression or a tropical storm later today or Saturday.

The potential tropical cyclone is expected to produce total rainfall accumulations through Sunday in the Bahamas of up to 2 to 4 inches, with isolated maximum amounts 6 inches. The U.S. Southeast Coast from central Florida into South Carolina can expect from 2 to 4 inches.

On the forecast track, the system is anticipated to move across the central and northwestern Bahamas today, and along or near the east coast of Florida Saturday and Saturday night.

For updated forecasts, visit: http://www.nhc.noaa.gov

AMHERST, Mass. - Cell biologist Thomas Maresca and senior research fellow Vikash Verma at the University of Massachusetts Amherst say they have, for the first time, directly observed and recorded in animal cells a pathway called branching microtubule nucleation, a mechanism in cell division that had been imaged in cellular extracts and plant cells but not directly observed in animal cells. Details appear this month in the Journal of Cell Biology.

In this work supported by NIH's National Institute of General Medical Sciences, the researchers set out to explore specific mechanics of cell division, what Verma calls "the rules of faithful and complete division," in fruit fly cells. In particular, they want to understand how structures called microtubules help to define where the cell splits in half during the division process.

Maresca explains, "This has been studied for a long time, since microscopy made it possible to see cells divide, but very intensely for 40 or 50 years. What are the cues that tell a cell where to divide? How does the cell know where to put the division plane? It's the ultimate conclusion of mitosis, the actual division of the cell into two."

In normal cell division, chromosomes line up near the center of the cell, where a structure called the spindle aligns copies of each chromosome by interacting with a bridge-like structure called the kinetochore. When all the chromosomes have been aligned, microtubules pull the chromosome copies apart like a zipper. The cell then physically divides at a location positioned between the segregated chromosomes to produce two daughter cells, each with a complete copy of the genome.

In imaging the microtubules, often described as nano-scale highways, the biologists noticed that the spatial cue for locating the division plane requires microtubules, Maresca says. "They grow out to touch the edges inside the cell membrane. Vikash found that the growing tips of the tubes, the 'plus-ends' that touch the membrane, say to the cell, 'This is where to divide.' Regulatory proteins get recruited to the site contacted by the plus-ends kicking into gear and a whole new pathway assembles a ring that will constrict like a purse string to split one large cell into two smaller ones."

Timing plays a role, as well, the researchers found. "It seems that all the microtubule tips have the special ability to trigger the purse-string pathway," Maresca says, "but over time, something changes and only the tips in the middle of the cell retain that ability." Referring to work published in eLife in February, he adds, "We found what we think is a very important spatial cue for how the cell positions its division plane."

Visualizing the behavior of microtubules during cell division in detail is typically hampered by the fact that so many microtubules are growing and shrinking at the same time throughout the cell, Verma says. "It's like many highways converging at the same place and time in the spindle. It looks like a Los Angeles freeway map." But by using a powerful technique called total internal reflection fluorescence (TIRF) microscopy, Verma could more easily visualize the dynamic properties of individual microtubules. Maresca adds, "We went from a stressful L.A. traffic jam into a Sunday-drive-on-a-country-road view."

That is when they witnessed the branching. Using multi-color TIRF microscopy, the researchers could now clearly see and quantitatively define the branching microtubule nucleation process. To the best of their knowledge, this had never been visualized before in real time in animal cells. "It was very exciting," Verma recalls.

Maresca says, "When you see such beautiful things right before your eyes, you just have to follow it. This project started out as an investigation of how cells define where they divide, but we saw this branching phenomenon so often and so clearly that we realized we had to look at it more closely. We don't think you could have seen the branching process as well in other model systems as you can in our fruit fly cells. It highlights the fact that every model system has its strengths and its weaknesses and, in this case, our cells and the phase at which we were imaging them just offered a uniquely beautiful, birds-eye view of branching. We could actually see all of this happening in real time before our eyes."

Once they could visualize the entire process of branching nucleation in a cell, he adds, "We knew we could next 'tag' proteins that regulate the process with different colors to further quantify fundamental parameters of the phenomenon. All of a sudden we realized that this is the first time one could see this happening in living animals cells."

Branching nucleation is fundamental and conserved, one of the essential parts of mitosis, but it's been difficult to directly visualize in other model systems, Maresca points out. "The course of this project was a reminder that some of the most exciting work we do as scientists is unplanned and, especially for microscopists, begins with seeing something in the cell unfold right before your eyes."

WASHINGTON -- Detecting landmines can be a challenging and slow process. Detecting them from a moving vehicle would make the process more speedy, but at the expense of accuracy.

At the Optical Society's (OSA) Laser Congress, held 29 September - 3 October 2019 in Vienna, Austria, researchers from the University of Mississippi, U.S.A., will report a new laser-based sensor that effectively detects buried objects even while the detector is in motion. This new device offers a significant improvement over existing technologies, which cannot be operated on the go and lose accuracy in the presence of external sources of sound or vibration.

Laser Doppler vibrometers (LDVs) combined with vibration excited in the ground have shown promise for detecting landmines and other buried objects, but their sensitivity to environmental vibrations mean they must be operated from a special stable platform. The device, called a Laser Multi Beam Differential Interferometric Sensor (LAMBDIS), provides comparable detection capabilities but is far less sensitive to motion, allowing it to be used aboard a moving vehicle.

"The lingering scourge of landmines presents a serious challenge to rapid and accurate interrogation of large areas from moving vehicles," said lead researcher Dr. Vyacheslav Aranchuk. "Our new device overcomes this challenge by using a series of laser beams and then combining their signals to create a rapid-detection scheme that also is robust enough to compensate for motion and other 'noise' that could overwhelm other techniques. LAMBDIS provides measurement of vibration fields with high sensitivity, while having low sensitivity to the whole body motion of the object, or sensor itself, allowing for the operation from a moving vehicle."

Measurements without a reference beam

To detect buried objects, LDVs are used in conjunction with an audio source such as a loudspeaker, or a seismic source such as a mechanical shaker. The sound or seismic waves cause the ground to vibrate. The LDV can detect subtle differences in the vibration pattern where an object is buried, provided that the detector is stationary and the environment is sufficiently vibration-free.

Operation of traditional LDVs is based on interference of light reflected from an object with a reference beam internal to the LDV. As a result, motion of the LDV itself can cause LDV signals to be significantly higher than, and indistinguishable from, signals caused by object vibration.

In the new work, the researchers used a linear array of 30 laser beams directed onto the interrogated area.

Optical elements, including a receiver lens and a shearing interferometer, are used to combine the light reflected from different points on the ground on a photodetector array (PDA) resulting in interference signals on the PDA outputs. The frequency of the signals is proportional to the vibration velocity between illuminated points due to the Doppler effect. Processing of the PDA signals reveals vibrations between illuminated points on the surface.

"Unlike LDVs, the LAMBDIS doesn't use an internal reference beam, but detects a Doppler shift by using interference of light reflected from different points on the object," said Aranchuk. "Due to the lack of a reference beam, the Doppler frequency caused by the sensor motion is practically the same for all reflected beams and is automatically subtracted from the interference signals. As a result, LAMBDIS has very low sensitivity to the motion of the sensor itself, while having high sensitivity to relative vibration between points on the object."

Successful field tests

Researchers report the LAMBDIS device performed well under a wide range of conditions in laboratory and field tests. LAMBDIS was able to detect buried objects 7.5 meters to 20 meters away and from a vehicle traveling at 3.8 meters per second (about 8.5 miles per hour) with comparable results to a stable platform-mounted LDV. Researchers tested the device both with airborne and seismic sound sources and with different scanning angles, suggesting the device could provide accurate results in a variety of real-world conditions.

In addition to detecting landmines, LDVs are commonly used to inspect automobiles and aircraft components, to assess bridge and structure vibrations, to calibrate equipment and study materials, and in dental and biomedical applications. LAMBDIS could benefit such applications in cases where environmental noise or movement hinders the use of LDV devices.

Inspired by octopuses, researchers have developed a structure that senses, computes and responds without any centralized processing - creating a device that is not quite a robot and not quite a computer, but has characteristics of both. The new technology holds promise for use in a variety of applications, from soft robotics to prosthetic devices.

"We call this 'soft tactile logic,' and have developed a series of prototypes demonstrating its ability to make decisions at the material level - where the sensor is receiving input - rather than relying on a centralized, semiconductor-based logic system," says Michael Dickey, co-corresponding author of a paper on the work and Alcoa Professor of Chemical and Biomolecular Engineering at North Carolina State University.

"Our approach was inspired by octopuses, which have a centralized brain, but also have significant neuronal structures throughout their arms. This raises the possibility that the arms can 'make decisions' based on sensory input, without direct instruction from the brain."

At the core of the soft tactile logic prototypes is a common structure: pigments that change color at different temperatures, mixed into a soft, stretchable silicone form. That pigmented silicone contains channels that are filled with metal that is liquid at room temperature, effectively creating a squishy wire nervous system.

Pressing or stretching the silicone deforms the liquid metal, which increases its electrical resistance, raising its temperature as current passes through it. The higher temperature triggers color change in the surrounding temperature-sensitive dyes. In other words, the overall structure has a tunable means of sensing touch and strain.

The researchers also developed soft tactile logic prototypes in which this same action - deforming the liquid metal by touch - redistributes electrical energy to other parts of the network, causing material to change colors, activating motors or turning on lights. Touching the silicone in one spot creates a different response than touching in two spots; in this way, the system carries out simple logic in response to touch.

"This is a proof of concept that demonstrates a new way of thinking about how we can engineer decision-making into soft materials," Dickey says.

"There are living organisms that can make decisions without relying on a rigid centralized processor. Mimicking that paradigm, we've shown materials-based, distributed logic using entirely soft materials."

The researchers are currently exploring ways to make more complex soft circuits, inspired by the sophisticated sensors and actuators found in biological systems.

The paper, "Materials tactile logic via innervated soft thermochromic elastomers," is published in the journal Nature Communications.

While computers have become smaller and more powerful and supercomputers and parallel computing have become the standard, we are about to hit a wall in energy and miniaturization. Now, Penn State researchers have designed a 2D device that can provide more than yes-or-no answers and could be more brainlike than current computing architectures.

"Complexity scaling is also in decline owing to the non-scalability of traditional von Neumann computing architecture and the impending 'Dark Silicon' era that presents a severe threat to multi-core processor technology," the researchers note in today's (Sept 13) online issue of Nature Communications.

The Dark Silicon era is already upon us to some extent and refers to the inability of all or most of the devices on a computer chip to be powered up at once. This happens because of too much heat generated from a single device. Von Neumann architecture is the standard structure of most modern computers and relies on a digital approach -- "yes" or "no" answers -- where program instruction and data are stored in the same memory and share the same communications channel.

"Because of this, data operations and instruction acquisition cannot be done at the same time," said Saptarshi Das, assistant professor of engineering science and mechanics. "For complex decision-making using neural networks, you might need a cluster of supercomputers trying to use parallel processors at the same time -- a million laptops in parallel -- that would take up a football field. Portable healthcare devices, for example, can't work that way."

The solution, according to Das, is to create brain-inspired, analog, statistical neural networks that do not rely on devices that are simply on or off, but provide a range of probabilistic responses that are then compared with the learned database in the machine. To do this, the researchers developed a Gaussian field-effect transistor that is made of 2D materials -- molybdenum disulfide and black phosphorus. These devices are more energy efficient and produce less heat, which makes them ideal for scaling up systems.

"The human brain operates seamlessly on 20 watts of power," said Das. "It is more energy efficient, containing 100 billion neurons, and it doesn't use von Neumann architecture."

The researchers note that it isn't just energy and heat that have become problems, but that it is becoming difficult to fit more in smaller spaces.

"Size scaling has stopped," said Das. "We can only fit approximately 1 billion transistors on a chip. We need more complexity like the brain."

The idea of probabilistic neural networks has been around since the 1980s, but it needed specific devices for implementation.

"Similar to the working of a human brain, key features are extracted from a set of training samples to help the neural network learn," said Amritanand Sebastian, graduate student in engineering science and mechanics.

The researchers tested their neural network on human electroencephalographs, graphical representation of brain waves. After feeding the network with many examples of EEGs, the network could then take a new EEG signal and analyze it and determine if the subject was sleeping.

"We don't need as extensive a training period or base of information for a probabilistic neural network as we need for an artificial neural network," said Das.

The researchers see statistical neural network computing having applications in medicine, because diagnostic decisions are not always 100% yes or no. They also realize that for the best impact, medical diagnostic devices need to be small, portable and use minimal energy.

Das and colleagues call their device a Gaussian synapse and it is based on a two-transistor setup where the molybdenum disulfide is an electron conductor, while the black phosphorus conducts through missing electrons, or holes. The device is essentially two variable resistors in series and the combination produces a graph with two tails, which matches a Gaussian function.

A new nanomaterial developed by scientists at the University of Bath could solve a conundrum faced by scientists probing some of the most promising types of future pharmaceuticals.

Scientists who study the nanoscale - with molecules and materials 10,000 smaller than a pinhead - need to be able to test the way that some molecules twist, known as their chirality, because mirror image molecules with the same structure can have very different properties. For instance one kind of molecule smells of lemons when it twists in one direction, and oranges when twisted the other way.

Detecting these twists is especially important in some high-value industries such as pharmaceuticals, perfumes, food additives and pesticides.

Recently, a new class of nanoscale materials have been developed to help distinguish the chirality of molecules. These so-called 'nanomaterials' usually consist of tiny twisted metal wires, that are chiral themselves.

However, it has become very hard to distinguish the twist of the nanomaterials from the twist of the molecules they are supposed to help study.

To solve this problem the team from the University of Bath's Department of Physics created a nanomaterial that is both twisted and it is not. This nanomaterial has equal number of opposite twists - meaning they cancel each other out. Usually, upon interacting with light, such material appears without any twist; how then could it be optimised to interact with molecules?

Using a mathematical analysis of the material's symmetry properties, the team discovered a few special cases, which can bring the 'hidden' twist to light and allow very sensitive detection of chirality in molecules.

Lead author Professor Ventsislav Valev, from the University of Bath Department of Physics, said: "This work removes an important roadblock for the entire research field and paves the way to ultra-sensitive detection of chirality in molecules, using nanomaterials."

PhD student Alex Murphy, who worked on the study, said: "Molecular chirality is an amazing property to study. You can smell chirality, since the same but oppositely twisted molecules smell of lemons and oranges. You can taste chirality, since one twist of Aspartame is sweet and the other is tasteless. You can feel chirality, since one twist of menthol gives a cool sensation to the skin while the other does not. You touch chirality expressed in the twist of seashells. And it is great to see chirality expressed in its interactions with the colours of laser light."

Researchers from University of Tennessee, IESEG School of Management, and Georgia State University published a new paper in the Journal of Marketing that investigates the role of firms' customer engagement initiatives in social media and analyzes how firms seek to influence digital sentiment by shaping customers' experiential interactions.

The study, forthcoming in the November issue of the Journal of Marketing, is titled "The Role of Marketer-Generated Content in Customer Engagement Marketing" and is authored by Matthijs Meire, Kelly Hewett, Michel Ballings, V. Kumar, and Dirk Van den Poel.

Marketers of experiential events, such as concerts, sports competitions, and other sponsored events, often post informational or emotional social media to drive engagement or influence customers' perceptions of their event experiences. For example, during an extensive delay before the first-ever concert at the Mercedes Benz stadium in Atlanta, Georgia, performed by Garth Brooks, the venue's management used social media to keep fans informed of efforts to resolve sound issues in the stadium in an attempt to reduce negative sentiment being expressed by attendees about their disappointing experience.

Hewett explains that "Our study attempts to answer these questions: Following a poor performance, can a marketer effectively engage customers and enhance the sentiment of customers' social media contributions based on the firm's own posts, and if so, what should those posts say? After a disappointing experience, should the firm's posts appeal to customers' emotions, such as the concert venue sharing images of a stadium packed with excited fans, or instead offer informational content such as the venue's efforts to address sound quality issues? Similarly, after a positive experience, should the firm post on social media and should the content be emotional, such as images of elated fans, or informational, such as details regarding upcoming events?"

Many firms track buyers' offline interactions with the goal of improving customers' reactions to their experiences. For example, customer contact centers track the speed of response, problem resolution, and wait times. Similarly, firms commonly design online content to coincide with customers' experiences, and face varied performance levels during customer interactions, enabling them to modify social media posts to correspond to those interactions.

Using evidence from a European soccer team's Facebook fan page, the researchers find that, if a firm's performance during customer interactions is held constant, the firm's own social media posts surrounding customers' experiences can influence the sentiment of customers' digital engagement. Informational, more so than emotional, content offers a substantial means to improve customer sentiment in the case of negative interaction event outcomes. For the team used in the study, an increase of roughly four informational posts from the team after a disappointing performance can increase positive sentiment by nearly 20 percent. Such increases in sentiment are shown to be valuable based on their ability to influence customers' purchase behavior.

Based on these findings, firms may also be able to influence customer sentiment surrounding firm or brand-related interactions by using personalized communications post-purchase. For instance, the beauty products chain Sephora sends recommendations and educational content to customers starting immediately after they make a purchase. Such mechanisms for responding to customers in a customized manner may help to further enhance the sentiment of customers' digital engagement and subsequent purchase behaviors.

In cases where purchase frequency is low, regularly tracking customers' digital engagement in social media can provide more frequent opportunities to impact customer sentiment and, ultimately, purchase behavior. Meire emphasizes that "Based on estimates that 40 percent of consumers follow their favorite brands on social media, there appears to be a sizable opportunity for firms to influence the sentiment of digital engagement."

The study's results should encourage firms to develop customer engagement marketing programs that involve customizing social media strategies based on their own performance during customers' interactions. They should post more informational content in social media surrounding poor performances and in general increase the volume of posts when performance is good.