Tech

A group of researchers have demonstrated that, from seven methods commonly used to test for viruses in untreated wastewater, an adsorption-extraction technique can most efficiently detect SARS-CoV-2. This gives us another tool to detect the presence and spread of the COVID-19 pandemic.

Tracking the spread of the COVID-19 pandemic is currently conducted by testing nasal swabs or saliva samples. Tools and techniques to track the spread of the pandemic by other means would be very beneficial; wastewater monitoring is a method that would allow us to monitor the spread of the pandemic at a much larger scale. This is not a new technique, and has been used for detecting non-enveloped viruses, but a conventional method for enveloped viruses such as SARS-CoV-2 had not been developed.

In the current work, co-authored by Assistant Professor Masaaki Kitajima from the Water Quality Control Engineering Laboratory at Hokkaido University, scientists report a fast, economical method to concentrate coronavirus in untreated wastewater. Murine hepatitis virus (MHV), a type of enveloped virus, is closely related to SARS-CoV-2 but does not affect humans, and is thus safe to use for testing the feasibility of the method. The study was published in Science of the Total Environment.

The scientists obtained MHV from mice feces and introduced it into samples of untreated wastewater collected from Brisbane, Australia. They attempted to recover and concentrate the MHV from these samples by seven different methods which are commonly used to test for non-enveloped viruses. The amount of recovered MHV was determined by a method called reverse transcription-quantitative PCR, where the RNA of the virus extracted, converted to DNA, the DNA is repeatedly duplicated, and the increase in amount of DNA is measured throughout the process.

The recovery was highest in the method that involved treating the sample with magnesium chloride and then filtering out the virus on a negatively-charged membrane; the second highest recovery was by a similar method without magnesium chloride. The advantages of these methods include an initial processing time of under 1 hour and the need only for cheap, widely available equipment and reagents. There are also drawbacks, such as the clogging of the filters that may increase processing time. However, to date, the need for reverse transcription-qPCR for the detection of the virus is unavoidable.

The next step would be to test this method in samples collected from areas where the pandemic is prevalent. There are two objectives: one is to show that the technique can be used for SARS-CoV-2, and the other is to show that the test can be used on samples from outside the lab.

"I hope this research contributes to the establishment of a standard protocol for the detection of SARS-CoV-2 in wastewater," says Assistant Professor Kitajima, "and this, in turn, accelerates investigations to enhance our understanding of COVID-19 epidemiology through wastewater surveillance." He is currently involved in a number of studies related to applying wastewater-based epidemiology to tracking the spread of the COVID-19 pandemic, and has collaborated with a number of scientists and research groups across the world in this endeavor.

An international research team led by The University of Manchester has revealed a nanomaterial that mirrors the "magic angle" effect originally found in a complex man-made structure known as twisted bilayer graphene - a key area of study in physics in recent years.

The new research shows that the special topology of rhombohedral graphite effectively provides an inbuilt "twist" and therefore offers an alternative medium to study potentially game-changing effects like superconductivity. "It is an interesting alternative to highly popular studies of magic-angle graphene" said graphene pioneer Professor Sir Andre Geim, a co-author of the study.

The team, led by Artem Mishchenko, Professor of Condensed Matter Physics at The University of Manchester published its findings in the journal Nature on 12 August 2020.

"Rhombohedral graphite can help to better understand materials in which strong electronic correlations are important - such as heavy-fermion compounds and high-temperature superconductors", said Professor Mishchenko.

A previous step-forward in two-dimensional materials research was the curious behaviour that stacking one sheet of graphene atop one another and twisting it to a 'magic angle' changed the bilayer's properties, turning it into a superconductor.

Professor Mishchenko and his colleagues have now observed the emergence of strong electron-electron interactions in a weakly stable rhombohedral form of graphite - the form in which graphene layers stack slightly differently compared to stable hexagonal form.

Interactions in twisted bilayer graphene are exceptionally sensitive to the twist angle. Tiny deviations of about 0.1 degree from the exact magic angle strongly supress interactions. It is extremely difficult to make devices with the required accuracy and, especially, find sufficiently uniform ones to study the exciting physics involved. The newly published findings on rhombohedral graphite has now opened an alternative route to accurately making superconductor devices.

Graphite, a carbon material made up of stacked graphene layers, has two stable forms: hexagonal and rhombohedral. The former is more stable, and has thus been extensively studied, while the latter is less so.

To better understand the new result, it is important to remember that the graphene layers are stacked in different ways in these two forms of graphite. Hexagonal graphite (the form of carbon found in pencil lead) is composed of graphene layers orderly stacked on top of each other. The metastable rhombohedral form has a slightly different stacking order, and this slight difference leads to a drastic change in its electronic spectrum.

Previous theoretical studies have pointed to the existence of all kinds of many-body physics in the surface states of rhombohedral graphite - including high-temperature magnetic ordering and superconductivity. These predictions could not be verified, however, since electron transport measurements on the material were completely lacking until now.

The Manchester team has been studying hexagonal graphite films for several years and have developed advanced technologies to produce high-quality samples. One of their techniques involves encapsulating the films with an atomically-flat insulator, hexagonal boron nitride (hBN), which serves to preserve the high electronic quality in the resulting hBN/hexagonal graphite/hBN heterostructures. In their new experiments on rhombohedral graphite, the researchers modified their technology to preserve the fragile stacking order of this less stable form of graphite.

The researchers imaged their samples, which contained up to 50 layers of graphene, using Raman spectroscopy to confirm that the stacking order in the material remained intact and that it was of high quality. They then measured electronic transport properties of their samples in the traditional way - by recording the resistance of the material as they changed the temperature and the strength of a magnetic field applied to it.

The energy gap can also be opened in the surface states of rhombohedral graphite by applying an electric field explains Professor Mishchenko: "The surface-state gap opening, which was predicted theoretically, is also an independent confirmation of the rhombohedral nature of the samples, since such a phenomenon is forbidden in hexagonal graphite."

In rhombohedral graphite thinner than 4nm, a band gap is present even without applying an external electric field. The researchers say they are as yet unsure of the exact nature of this spontaneous gap opening (which occurs at the "charge neutrality"- the point at which densities of electrons and holes are balanced), but they are busy working on answering this question.

"From our experiments in the quantum Hall regime, we see that the gap is of a quantum spin Hall nature, but we do not know whether the spontaneous gap opening at the charge neutrality is of the same origin," adds Professor Mishchenko. "In our case, this gap opening was accompanied by hysteretic behaviour of the material's resistance as a function of applied electric or magnetic fields. This hysteresis (in which the resistance change lags behind the applied fields) implies that there are different electronic gapped phases separated into domains - and these are typical of strongly correlated materials."

Further investigation of rhombohedral graphite could shed more light on the origin of many-body phenomena in strongly correlated materials such as heavy-fermion compounds and high-temperature superconductors, to name but two examples.

Synthetic polymers have changed the world around us, and it would be hard to imagine a world without them. However, they do have their problems. It is for instance hard from a synthetic point of view to precisely control their molecular structure. This makes it harder to finely tune some of their properties, such as the ability to transport ions. To overcome this problem, University of Groningen assistant professor Giuseppe Portale decided to take inspiration from nature. The result was published in Science Advances on July 17: a new class of polymers based on protein-like materials that work as proton conductors and might be useful in future bio-electronic devices.

'I have been working on proton conducting materials on and off since my PhD', says Portale. 'I find it fascinating to know what makes a material transport a proton so I worked a lot on optimizing structures at the nanoscale level to get greater conductivity.' But it was only a few years ago that he considered the possibility of making them from biological, protein-like structures. He came to this idea together with professor Andreas Hermann, a former colleague at the University of Groningen, now working at the DWI - Leibniz Institute for Interactive Materials in Germany. 'We could immediately see that proton-conducting bio-polymers could be very useful for applications like bio-electronics or sensors', Portale says.

More active groups, more conductivity

But first, they had to see if the idea would work. Portale: 'Our first goal was to prove that we could precisely tune the proton conductivity of the protein-based polymers by tuning the number of ionisable groups per polymer chain'. To do this, the researchers prepared a number of unstructured biopolymers that had different numbers of ionisable groups, in this case, carboxylic acid groups. Their proton conductivity scaled linearly with the number of charged carboxylic acid groups per chain. 'It was not groundbreaking, everybody knows this concept. But we were thrilled that we were able to make something that worked as expected', Portale says.

For the next step, Portale relied on his expertise in the field of synthetic polymers: 'I have learned over the years that the nanostructure of a polymer can greatly influence the conductivity. If you have the right nanostructure, it allows the charges to bundle together and increase the local concentration of these ionic groups, which dramatically boosts proton conductivity.' Since the first batch of biopolymers was completely amorphous, the researchers had to switch to a different material. They decided to use a known protein that had the shape of a barrel. 'We engineered this barrel-like protein and added strands containing carbocyclic acid to its surface', Portale explains. 'This increased conductivity greatly.'

Novel Spider silk polymer

Unfortunately, the barrel-polymer was not very practical. It had no mechanical strength and it was difficult to process, so Portale and his colleagues had to look for an alternative. They landed on a well-known natural polymer: spider silk. 'This is one of the most fascinating materials in nature, because it is very strong but can also be used in many different ways', says Portale. 'I knew spider silk has a fascinating nanostructure, so we engineered a protein-like polymer that has the main structure of spider silk but was modified to host strands of carbocyclic acid.'

The novel material worked like a charm. 'We found that it self-assembles at the nanoscale similarly to spider silk while creating dense clusters of charged groups, which are very beneficial for the proton conductivity', Portale explains. 'And we were able to turn it into a robust centimetre-sized membrane.' The measured proton conductivity was higher than any previously known biomaterials, but they are not there yet according to Portale: 'This was mainly fundamental work. In order to apply this material, we really have to improve it and make it processable.'

Dreams

But even though the work is not yet done, Portale and his co-workers can already dream about applying their polymer: 'We think this material could be useful as a membrane in fuel cells. Maybe not for the large scale fuel cells that you see in cars and factories, but more on a small scale. There is a growing field of implantable bio-electronic devices, for instance, glucose-powered pacemakers. In the coming years, we hope to find out if our polymer can make a difference there, since it is already bio-compatible.'

For the short term, Portale mainly thinks about sensors. 'The conductivity we measure in our material is influenced by factors in the environment, like humidity or temperature. So if you want to store something at a certain humidity you can place this polymer between two electrodes and just measure if anything changes.' However, before all these dreams come true, there are a lot of questions to be answered. 'I am very proud that we were able to control these new materials on a molecular scale and build them from scratch. But we still have to learn a lot about their capabilities and see if we can improve them even further.'

Jointly with cooperation partners, a researcher of Karlsruhe Institute of Technology (KIT) has developed "porous liquids": Nanoparticles, that are able to separate gas molecules of different sizes from each other, float - finely distributed - in a solvent. This is because the particles have empty pores, through whose openings only molecules of a certain size can penetrate. These porous liquids may be used directly or processed into membranes that efficiently separate propene from gaseous mixtures. Propen, in turn, is employed as the starting material for propylene, a widely used plastic material. This could replace the energy-intensive distillation that has been the common procedure up to now. The team reports on the results in Nature Materials. (DOI: 10.1038/s41563-020-0764-y).

Propene, also known as propylene, is one of the most important raw materials for the chemical industry, of which around 100 million tons are used up worldwide every year. Polypropylene, a real "mass plastic", produced from propene is mainly used for packaging, but also in industries such as construction and automotive. Propene is mainly obtained by processing crude oil or natural gas. In this process, it is separated from other gases by distillation and then purified. "In the technical literature, it is assumed that gas separation in petrochemistry using membranes would only cost one fifth of the energy required for distillation. In view of the required high quantities of propene, this means that the release of huge amounts of the greenhouse gas CO2 can be avoided", says Junior Research Group Leader Dr. Alexander Knebel from the KIT Institute of Functional Interfaces who conducted research at Leibniz Universität Hannover and in Saudi Arabia until 2019.

The chemist is a major contributor to a research project that, for the first time, raises interest in the petrochemical industry as regards the use of membranes for the separation of propene. Knebel's cooperation partners were scientists from Leibniz Universität Hannover, King Abdullah University of Science and Technology and the Deutsches Institut für Kautschuktechnologie.

Metal-organic framework distributed in a liquid for the first time

The researchers started their work with the solid material ZIF-67 (zeolitic imidazole framework) whose atoms form a metal-organic framework with 0.34 nanometer-wide pore openings. In doing so, they systematically modified the surface of ZIF-67 nanoparticles. "This enabled us to finely disperse a metal-organic framework in liquids such as cyclohexane, cyclooctane or mesitylene," says Knebel joyfully. Scientists call the resulting dispersion "porous liquid".

Gaseous propene needs much longer to pass through a column filled with the porous liquid than methane, for example. This is because propene is retained, as it were, in the pores of the nanoparticles, while the smaller methane molecules smoothly pass through. "We want to exploit this property of the dispersion in the future to produce liquid separation membranes," states Knebel.

Yet, porous liquids can also be used to produce solid separation membranes with particularly advantageous properties. The researchers produced membranes from a plastic material and the chemically modified ZIF-67. They succeeded in increasing the proportion of modified ZIF-67 in the membrane to 47.5 percent without making it mechanically unstable. When the scientists passed a gas mixture consisting of equal parts of propene and propane over two membranes arranged in series, they obtained propene with a purity of at least 99.9 percent, even though the two gas molecules differ in size by not more than 0.2 nanometers.

Besides its separation efficiency, the quantity of a gas mixture that can be passed through in a certain time is decisive for the practical use of such a membrane. This flow rate was at least three times higher with the new membranes than with previous materials. With the separation values achieved, Knebel is convinced that it would pay off for the petrochemical industry for the first time to use membranes instead of conventional distillation processes for gas separation.

It is crucial for the performance of the membranes that as many metal-organic particles as possible can be distributed uniformly in the plastic and that the pores in the nanoparticles are not clogged by solvents during membrane production, i.e. remain empty, so to speak. "We were able to achieve both goals because we did not directly incorporate solid particles into the membrane, but instead proceeded via the porous liquids even though this looks like a detour," explains Knebel.

New Haven, Conn. -- A nifty move with nitrogen has brought the world one step closer to creating a range of useful products -- from dyes to pharmaceuticals -- out of thin air.

The discovery comes from a team of Yale chemists who found a way to combine atmospheric nitrogen with benzene to make a chemical compound called aniline, which is a precursor to materials used to make an assortment of synthetic products.

A study describing the process appears in the journal Nature.

"In the long run, we hope to learn how to use the abundant nitrogen in the air as a resource for synthesizing the products needed by society," said Yale chemistry professor Patrick Holland, senior author of the study.

Much attention has been focused on "nitrogen fixation," a process by which atmospheric nitrogen is used to create ammonia. But as Holland and his colleagues point out, there are many other compounds, materials, and processes that could use nitrogen in other forms -- if researchers can find ways to make them with atmospheric nitrogen.

Holland said previous attempts by other researchers to combine atmospheric nitrogen and benzene failed. Those attempts used highly reactive derivatives of benzene that would degrade before they could produce a chemical reaction with nitrogen.

Holland and his colleagues used an iron compound to break down one of the chemical bonds in benzene. They also treated the nitrogen with a silicon compound that allowed the nitrogen to combine with benzene.

"Fundamentally, we're showing a new way of thinking about how to encourage nitrogen to form new bonds that may be adaptable to making other products," Holland said.

To prevent the spread of COVID-19, many universities canceled classes or held them online this spring -- a change likely to continue for many this fall. As a result, hands-on chemistry labs are no longer accessible to undergraduate students. In a new study in the Journal of Chemical Education, researchers describe an alternative way to engage students: a virtual game, modeled on an escape room, in which teams solve chemistry problems to progress and "escape."

While some lab-related activities, such as calculations and data analysis, can be done remotely, these can feel like extra work. Faced with the cancellation of their own in-person laboratory classes during the COVID-19 pandemic, Matthew J. Vergne and colleagues looked outside-the-box. They sought to develop an online game for their students that would mimic the cooperative learning that normally accompanies a lab experience.

To do so, they designed a virtual escape game with an abandoned chocolate factory theme. Using a survey-creation app, they set up a series of "rooms," each containing a problem that required students to, for example, calculate the weight of theobromine, a component of chocolate. They tested the escape room game on a class of eight third- and fourth-year undergraduate chemistry and biochemistry students. The researchers randomly paired the students, who worked together over a video conferencing app. In a video call afterward, the students reported collaborating effectively and gave the game good reviews, say the researchers, who also note that it was not possible to ensure students didn't use outside resources to solve the problems. Future versions of the game could potentially incorporate online simulations or remote access to computer-controlled lab instrumentation on campus, they say.

Contrary to popular wisdom, daily social media use is not a strong or consistent risk factor for depressive symptoms among adolescents, according to a new study by Columbia University Mailman School of Public Health researchers. The results are published in the Journal of Adolescent Health.

"Increasingly, teenagers are active on social media, particularly during the pandemic, as they have to rely on Instagram, TikTok, and other platforms to stay in touch with friends," says first author Noah Kreski, MPH, who conducted the research as a practicum project as a Columbia Mailman School student and currently works as a data analyst in the Department of Epidemiology. "While some adults have voiced concerns over the potential mental health risks of this behavior, our research finds no compelling evidence to suggest that social media use meaningfully increases adolescents' risk of depressive symptoms."

The researchers analyzed survey data collected by Monitoring the Future, an ongoing study of the behaviors, attitudes, and values of Americans from adolescence through adulthood, representing 74,472 8th and 10th grade students between 2009 to 2017. They assessed depressive symptoms to establish underlying depression risk, which they controlled for in their analysis to understand how daily social media use might contribute to depression.

Daily social media use among 8th and 10th grade students increased from 61 percent to 89 percent among girls, and from 46 percent to 75 percent among boys, from 2009 to 2017. Daily social media use was not associated with depressive symptoms after accounting for the fact that the adolescents who frequently use social media have worse mental health to begin with. However, among girls who had the lowest risk for depressive symptoms, daily social media use was weakly associated with symptoms, though due to low risk, the overall prevalence of symptoms in that group was small. Among boys, daily social media use was not linked to increased depressive symptoms, and some evidence suggested that daily social media use may actually be protective against depression.

"Daily social media use does not capture the diverse ways in which adolescents use social media, which may be both positive and negative depending on the social context," says senior author Katherine Keyes, PhD, associate professor of epidemiology at Columbia Mailman School. "Future research could explore the specific behaviors and experiences of young people using social media, as well as more frequent engagement with the various platforms."

Background on Adolescent Depression and Social Media Use

After almost 50 years of stability, recent evidence has indicated unprecedented increases in adolescent depression, depressive symptoms, and suicidal behavior, particularly among girls. There has been widespread speculation that increasing use of smartphones and social media has contributed to these trends. Proponents of this hypothesis note that adolescents are increasingly isolated from face-to-face interaction, experience cyber-bullying, and face challenges to self-esteem and self-worth through curated online images of peers. On the other hand, social media is often a positive outlet, and its use may have positive effects on adolescent self-esteem. Social networking sites provide a space for content that is positive or humorous, particularly valuable to adolescents who are depressed. Many young people seek out support and advice on social media, particularly those with moderate to severe depressive symptoms.

WASHINGTON, August 11, 2020 -- Since the COVID-19 virus spreads through respiratory droplets, researchers in India set out to explore how droplets deposited on face masks or frequently touched surfaces, like door handles or smartphone touch screens, dry.

Droplets can be expelled via the mouth or nose while coughing, sneezing or simply talking. These droplets are tiny, around twice the width of a human hair, and studies have shown a substantially reduced chance of infection once they dry.

In Physics of Fluids, from AIP Publishing, Rajneesh Bhardwaj and Amit Agrawal, professors at IIT Bombay, publish findings that surface wetting properties to reduce the drying time of droplets could help lessen the risk of infection from coronaviruses.

"We wanted to quantify the droplet drying time on various surfaces and make a recommendation for the ideal types of surfaces for masks and personal protective equipment (PPE) based on the drying time," said Bhardwaj.

By studying the drying time of a droplet for different contact angles, the expected chances of survival of the coronavirus on a surface can be estimated by using a mathematical physics model.

"Our calculations of the drying time as a function of contact angle show that the droplet dries roughly four times faster on the hydrophilic surface that attracts water than on the one that repels water. This will drastically reduce the chances of virus survival," Bhardwaj said.

Their work also shows that, by tailoring the surface wettability and drying time, the chances of infection can be reduced.

"Making a surface more hydrophilic reduces the drying time, and it is advisable to use it for masks, PPE and frequently touched surfaces where outbreaks are most likely to occur, such as the common areas within hospitals," said Agrawal.

In the case of N95 respirators, surgical masks and PPE bodywear, a reduction to a contact angle of a hydrophilic surface implies that the chances of infection of COVID-19 will be cut in half.

"We recommend reducing the contact angle of the surface of face masks and frequently touched surfaces," Agrawal said.

The biggest surprise was their finding that the maximum drying time occurs at an intermediate contact angle value of 148 degrees.

"This implies that a superhydrophobic surface needs to be made even more superhydrophobic to reduce the drying time," Agrawal said. "This is counterintuitive, because we normally think of making a surface more hydrophilic, reducing the contact angle, to reduce the drying time."

This work provides a better understanding of coronavirus survival within a drying droplet, which may be helpful for predicting the survival of other transmissible diseases spread through respiratory droplets, such as the flu.

COLUMBUS, Ohio - Bifocal contact lenses aren't just for aging eyes anymore. In nearsighted kids as young as 7 years old, multifocal contact lenses with a heavy dose of added reading power can dramatically slow further progression of myopia, new research has found.

In the three-year clinical trial of almost 300 children, a bifocal contact lens prescription with the highest near-work correction slowed nearsightedness progression by 43 percent when compared to single-vision contact lenses.

Though many adults in their 40s need time to adjust to their first multifocal contact lens prescription, the kids using the same commercially available soft contact lenses in the study had no vision problems despite the strong correction. Multifocal lenses for nearsighted patients correct for clear distance vision and include an "add" of focal power for near work that challenges middle-aged eyes.

"Adults need multifocal contact lenses because they can no longer focus their eyes to read," said Jeffrey Walline, professor of optometry at The Ohio State University and lead author of the study.

"Kids can still focus their eyes, even though they're wearing multifocal contact lenses, so it's like fitting them with normal contact lenses. They adapt much easier than adults."

The study, known as BLINK (Bifocal Lenses In Nearsighted Kids), is published today (Aug. 11) in the Journal of the American Medical Association.

In nearsightedness, or myopia, the eye grows in an uncoordinated way into an elongated shape, for reasons that remain a mystery. Animal studies clued scientists in to contact lenses' potential to keep eye growth in check by using the reading portion of multifocal contact lenses to focus some light in front of the retina - the light-sensitive layer of tissue lining the back of the eye - to slow the eye's growth.

"These multifocal contact lenses move with the eyes and provide more focus in front of the retina than glasses do," said Walline, also associate dean for research in Ohio State's College of Optometry. "And we want to slow the growth of the eye because nearsightedness is caused by the eye growing too long."

This research and other studies have led to advances in the treatment landscape for nearsighted children, Walline said. Options include multifocal contact lenses, contact lenses that reshape the cornea during sleep called orthokeratology, a specific type of eye drop called atropine, and specialty glasses.

Nearsightedness is more than an inconvenience. Myopia increases the risk for cataracts, detached retina, glaucoma and myopic maculopathy. All of these conditions can lead to loss of vision, even when wearing glasses or contact lenses. There are also quality of life factors - less severe nearsightedness improves the chances for successful laser surgery to correct vision and is not as disabling when no correction is worn, such as upon waking in the morning.

Myopia is also common, affecting about one-third of adults in the United States, and is becoming more prevalent - because, the scientific community believes, children are spending less time outdoors now than in the past. Nearsightedness tends to begin between the ages of 8 and 10 and progress up to about age 18.

Walline has been studying contact lens use in children for years and has found that in addition to the vision benefits, contact lenses also improve kids' self-esteem.

"The youngest nearsighted kids I've studied with were 7," he said. "Not all 25-year-olds can tolerate contact lens wear. About half of 7-year-olds can adapt to contact lenses reasonably, and almost all 8-year-olds can."

In this trial, conducted at Ohio State and the University of Houston, nearsighted children age 7-11 years were randomized into one of three groups of contact-lens wearers: single vision or multifocal prescriptions with a medium reading add of 1.50 diopters or a high add of 2.50 diopters. Diopters are a unit of measurement of the optical power needed to correct vision.

As a group, the participants' average prescription at the start of the study was -2.39 diopters. After three years, both the degree of myopia progression and the extent of eye growth were lower in the kids who had worn the high-add lenses. On average, the three-year eye growth among kids with the high-add bifocals was .23 millimeters less than in kids wearing single-vision lenses. Medium-add lenses did not slow eye growth any more than single vision lenses.

The researchers were aware of the need to balance the reduction of eye growth with any risks associated with subjecting children to strong reading power long before they need that level of correction. When testing their ability to read gray letters on a white background, there was a two-letter difference between single-vision lens wearers and those wearing multifocal lenses.

"This was about finding a sweet spot," Walline said. "And really, what we found was that even the high-add power doesn't reduce their vision much at all, and certainly not in a way that is clinically relevant."

The research team is continuing to follow the same participants, treating them all with the high-add bifocal lenses for two years and then switching them all to single-vision contact lenses.

"The question is, we have slowed the growth of the eye, but what happens when we take them out of the treatment? Will they go back to where they were preprogrammed to originally? The permanence of the treatment effect is what we'll be examining," Walline said.

Imagine plugging in to your brick house.

Red bricks -- some of the world's cheapest and most familiar building materials -- can be converted into energy storage units that can be charged to hold electricity, like a battery, according to new research from Washington University in St. Louis.

Brick has been used in walls and buildings for thousands of years, but rarely has been found fit for any other use. Now, chemists in Arts & Sciences have developed a method to make or modify "smart bricks" that can store energy until required for powering devices. A proof-of-concept published Aug. 11 in Nature Communications shows a brick directly powering a green LED light.

"Our method works with regular brick or recycled bricks, and we can make our own bricks as well," said Julio D'Arcy, assistant professor of chemistry. "As a matter of fact, the work that we have published in Nature Communications stems from bricks that we bought at Home Depot right here in Brentwood (Missouri); each brick was 65 cents."

Walls and buildings made of bricks already occupy large amounts of space, which could be better utilized if given an additional purpose for electrical storage. While some architects and designers have recognized the humble brick's ability to absorb and store the sun's heat, this is the first time anyone has tried using bricks as anything more than thermal mass for heating and cooling.

D'Arcy and colleagues, including Washington University graduate student Hongmin Wang, first author of the new study, showed how to convert red bricks into a type of energy storage device called a supercapacitor.

"In this work, we have developed a coating of the conducting polymer PEDOT, which is comprised of nanofibers that penetrate the inner porous network of a brick; a polymer coating remains trapped in a brick and serves as an ion sponge that stores and conducts electricity," D'Arcy said.

The red pigment in bricks -- iron oxide, or rust -- is essential for triggering the polymerisation reaction. The authors' calculations suggest that walls made of these energy-storing bricks could store a substantial amount of energy.

"PEDOT-coated bricks are ideal building blocks that can provide power to emergency lighting," D'Arcy said. "We envision that this could be a reality when you connect our bricks with solar cells -- this could take 50 bricks in close proximity to the load. These 50 bricks would enable powering emergency lighting for five hours.

"Advantageously, a brick wall serving as a supercapacitor can be recharged hundreds of thousands of times within an hour. If you connect a couple of bricks, microelectronics sensors would be easily powered."

Doctors are overworked and in short supply across the globe, but they could soon be assisted by machine learning to help reduce errors in primary care. AI symptom checkers are tremendously valuable in providing medical information and safe triaging advice to users, however, none of them performs diagnosis like a doctor. Unlike doctors, existing symptom checkers provide advice based on correlations alone - and correlation is not causation. Researchers at Babylon have, for the first time that we know of, used the principles of causal reasoning to enable AI to diagnose written test cases.

The researchers used a new approach, known as causal machine learning - which is gaining increased traction in the AI community - to act as an 'imagination' so the AI could consider what symptoms it might see if the patient had an illness different to the one it was considering. The peer-reviewed research, published in Nature Communications, shows that disentangling correlation from causation makes the AI significantly more accurate.

Dr Jonathan Richens, Babylon scientist and lead author, said: "We took an AI with a powerful algorithm, and gave it the ability to imagine alternate realities and consider 'would this symptom be present if it was a different disease'? This allows the AI to tease apart the potential causes of a patient's illness and score more highly than over 70% of the doctors on these written test cases."

Dr Ali Parsa, CEO and Founder, Babylon, said: "Half the world has almost no access to healthcare. We need to do better. So it's exciting to see these promising results in test cases. This should not be sensationalised as machines replacing doctors, because what is truly encouraging here is for us to finally get tools that allow us to increase the reach and productivity of our existing healthcare systems. AI will be an important tool to help us all end the injustice in the uneven distribution of healthcare, and to make it more accessible and affordable for every person on Earth."

A pool of over 20 Babylon GPs created 1,671 realistic written medical cases - these included typical and atypical examples of symptoms for more than 350 illnesses. Each case was authored by a single doctor and then verified by multiple other doctors to ensure it represented a realistic diagnostic case. A separate group of 44 Babylon GPs were then each given at least 50 written cases (the mean was 159) to assess. The doctors listed the illnesses they considered most likely (on average returning 2.58 potential diseases for each diagnosis). They were measured for accuracy by the proportion of cases where they included the true disease in their diagnosis. Babylon's AI took the same tests and used both an older algorithm based on correlations (created specifically for this research, not taken from our product) and the newer, causal one. For each test, the AI could only report as many answers as the doctor had.

The doctors had a mean score of 71.40% (± 3.01%) and ranged from 50-90%. The older correlative algorithm performed on par with the average doctor, achieving 72.52% (± 2.97%). The new causal algorithm scored 77.26% (± 2.79%) which was higher than 32 of the doctors, equal to 1, and lower than 11.

Dr Tejal Patel, Associate Medical Director and GP, Babylon, said: "I'm excited that one day soon this AI could help support me and other doctors reduce misdiagnosis, free up our time and help us focus on the patients who need care the most. I look forward to when this type of tool is standard, helping us enhance what we do."

Dr Saurabh Johri, Chief Scientist and author, Babylon, added: "Interestingly, we found that the AI and doctors complemented each other - the AI scored more highly than the doctors on the harder cases, and vice versa. Also, the algorithm performed particularly well for rare diseases which are more commonly misdiagnosed, and more often serious. Switching from using correlations improved accuracy for around 30% of both rare and very-rare conditions."

It is not necessary to alter the underlying models of disease that an AI uses in order to get an improvement in accuracy. It is a benefit that would apply to existing correlative algorithms, including those outside of the medical setting.

Dr Ciaran Lee, study author, formerly of Babylon and honorary lecturer at UCL, said: "Causal machine learning allows us to ask richer, more natural questions about medicine. This method has huge potential to improve every other current symptom checker, but it can also be applied to many other problems in healthcare and beyond - that's why causal AI is so impressive, it's universal."

This technology paves the way for a future partnership between clinicians and AI that will speed up a doctor's diagnosis, improve accuracy, free up time for clinicians and improve patient outcomes and patient experiences. It has the potential to augment the work of clinicians and continue to drive a better healthcare system for patients.

This new causal algorithm is not yet present in Babylon's publicly available app. It will only be released after further development and testing, and once it has met all necessary regulatory approvals in the UK and other markets where it will be released.

What The Viewpoint Says: Guidelines from the American Academy of Pediatrics on K-12 school reentry are discussed in this Viewpoint.

Authors: C. Jason Wang, M.D., Ph.D., of the Stanford University School of Medicine in Stanford, California, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamapediatrics.2020.3871)

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

Synchronization, in which a complex system operates as one body, is an important phenomenon that takes place in an enormous range of scales -- from subatomic particles to galaxies. In biology, fish, birds, and even cells synchronize in order to survive. Group synchronization is essential to human beings, and critical to our physical and mental health. Examples of synchronization can be seen in drivers on the road or in a crowd of people clapping hands together. Today, in order for a group of people to make a decision, they don't have to meet. Rather, there is a complex network of connections that enables them to make decisions. The phenomenon of synchronization between humans in a complex network is necessary for understanding decision-making, understanding the spread of fake news, political science, economics and the spread of diseases, yet it hasn't been studied to date.

To contribute to existing knowledge about human synchronization, and to investigate it for the first time in a measurable and accurate way, Dr. Moti Fridman, of the Kofkin Faculty of Engineering at Bar-Ilan University, Prof. Nir Davidson, of the Weizmann Institute, and Elad Shniderman, from Stony Brook University in New York created a musical ensemble that acted like a network. Their findings were published today (August 11, 2020) in the journal Nature Communications.

The ensemble was composed of 16 violinists wearing headphones. Each of the violinists repeatedly played an identical short musical phrase, and heard his/her own performance, along with the performance of two or more violinists, through the headphones. Visual information was also neutralized by separating the musicians with partitions. All they were asked to do was to synchronize with each other, or in other words, to play along with what they heard in the headphones.

The experimental setup created by the researchers allowed them to control the connectivity of the network, such as how many of the members of the ensemble each musician was connected to and the intensity in which each musician heard the other musicians. What the musicians heard in the headphones was one or two violinists or more playing with them in real time while an increasing delay was imposed on the system. "Here we have a different phenomenon than a regular musical piece. There is no global clock, but many people within a certain network of communication responding independently. In fact, it's an aesthetic object that reveals the behavior of people in a group personally, or as an ensemble," says Fridman.

"By introducing a delay between the coupled violinists so that each violinist heard what his/her neighbors played a few seconds ago, we prevent the network from reaching a synchronized state," says Fridman. This is called a frustrated situation and is well studied in different types of networks. According to current network theory models, in a frustrated state each node will try to compromise between all its inputs.

"Humans behave differently," Dr. Fridman explains. "In a state of frustration they don't look for a 'middle', but ignore one of the inputs. This is a critical phenomenon that is changing the dynamics of the network. It has not been addressed to date because the measurements weren't clean and couldn't be shown."

The research conducted by Dr. Fridman and his colleagues, which actually began as a scientific-artistic project for the Fetter Museum of Nanoscience & Art at Bar-Ilan University, offers two innovations: the first is methodological -- a platform that measures human network dynamics accurately and cleanly. The second is evidence that a human network has two unique characteristics: the flexibility to change pace, and the ability to filter, and even ignore, inputs that create frustration. These capabilities fundamentally change the dynamics of human networks relative to other networks and necessitate the use of a new model to predict human behavior.

"If you take humans and you study how they clap together, you have no control over who hears what. While working on this project we discovered that human networks behave differently than any other network we've ever measured. Human networks are able to change their inner structure in order to reach a better solution than what's possible in existing models. This concept is the core of our scientific and aesthetic discovery," says Fridman.

The research has led to a new model for simulating human networks, which is important for several applications. The dynamics of human networks are essential for understanding decision making in groups which is a wide subject related to economics, politics, human sciences, and more. Since the experiment is the first to measure the dynamics of complex networks, this can be beneficial to understanding how and when a group of people in a social network, which is exposed to false information, arrives at wrong conclusions. It can prevent what is known as "fake news" from spreading without control. In addition, the research is related to epidemic control and understanding how many connections we can preserve and still prevent an epidemic from spreading.

The results are also related to any network where each node in the network has decision-making ability, such as autonomous cars, or introducing AI into our highly-connected world. This model can predict with high accuracy the dynamic of such systems, beyond what was possible before.

Materials scientists studying recharging fundamentals made an astonishing discovery that could open the door to better batteries, faster catalysts and other materials science leaps.

Scientists from Idaho National Laboratory and University of California San Diego scrutinized the earliest stages of lithium recharging and learned that slow, low-energy charging causes electrodes to collect atoms in a disorganized way that improves charging behavior. This noncrystalline "glassy" lithium had never been observed, and creating such amorphous metals has traditionally been extremely difficult.

The findings suggest strategies for fine-tuning recharging approaches to boost battery life and--more intriguingly--for making glassy metals for other applications. The study appeared online this week in Nature Materials.

Lithium metal is a preferred anode for high-energy rechargeable batteries. Yet the recharging process (depositing lithium atoms onto the anode surface) is not well understood at the atomic level. The way lithium atoms deposit onto the anode can vary from one recharge cycle to the next, leading to erratic recharging and reduced battery life.

The INL/UCSD team wondered whether recharging patterns were influenced by the earliest congregation of the first few atoms, a process known as nucleation.

"That initial nucleation may affect your battery performance, safety and reliability," said Gorakh Pawar, an INL staff scientist and one of the paper's two lead authors.

The researchers combined images and analyses from a powerful electron microscope with liquid-nitrogen cooling and computer modeling. The cryo-state electron microscopy allowed them to see the creation of lithium metal "embryos," and the computer simulations helped explain what they saw.

In particular, they discovered that certain conditions created a less structured form of lithium that was amorphous (like glass) rather than crystalline (like diamond).

"The power of cryogenic imaging to discover new phenomena in materials science is showcased in this work," said Shirley Meng, who led UC San Diego's pioneering cryo-microscopy work. The imaging and spectroscopic data are often convoluted, she said. "True teamwork enabled us to interpret the experimental data with confidence because the computational modeling helped decipher the complexity."

Pure amorphous elemental metals had never been observed before now. They are extremely difficult to produce, so metal mixtures (alloys) are typically required to achieve a "glassy" configuration, which imparts powerful material properties.

During recharging, glassy lithium embryos were more likely to remain amorphous throughout growth. While studying what conditions favored glassy nucleation, the team was surprised again.

"We can make amorphous metal in very mild conditions at a very slow charging rate," said Boryann Liaw, an INL directorate fellow and INL lead on the work. "It's quite surprising."

That outcome was counterintuitive because experts assumed that slow deposition rates would allow the atoms to find their way into an ordered, crystalline lithium. Yet modeling work explained how reaction kinetics drive the glassy formation. The team confirmed those findings by creating glassy forms of four more reactive metals that are attractive for battery applications.

The research results could help meet the goals of the Battery500 consortium, a Department of Energy initiative that funded the research. The consortium aims to develop commercially viable electric vehicle batteries with a cell level specific energy of 500 Wh/kg. Plus, this new understanding could lead to more effective metal catalysts, stronger metal coatings and other applications that could benefit from glassy metals.

INL is a U.S. Department of Energy (DOE) national laboratory that performs work in each of DOE's strategic goal areas: energy, national security, science and environment. INL is the nation's center for nuclear energy research and development. Day-to-day management and operation of the laboratory is the responsibility of Battelle Energy Alliance.

See more INL news at http://www.inl.gov. Follow us on social media: Twitter, Facebook, Instagram and LinkedIn.

Philadelphia, August 11, 2020 - A team of researchers at Children's Hospital of Philadelphia (CHOP) affiliated with the CHOP Epilepsy Neurogenetics Initiative (ENGIN) further bridged the gap between genomic information and clinical outcome data by systematically linking genetic information with electronic medical records, focusing on how genetic neurological disorders in children develop over time. The findings were published today in the journal Genetics in Medicine.

Over the last decade, more than 200 genetic causes of epilepsy have been identified. Genetic changes can be found in up to 30% of Developmental and Epileptic Encephalopathies (DEE), severe brain disorders that can cause aggressive seizures, cognitive and neurological impairment and, in some cases, early death. Identifying a causative gene is often the first step of improving treatment, since many children with these conditions do not respond to current treatment methods.

Even though collectively common, each causal gene is only found in 1% or less of the overall patient population, often making it difficult to generate enough clinical information to provide families and their providers with reliable information on how these conditions develop over time. Additionally, while genomic data is gathered in a standardized manner, the patient's phenotype -- a set of clinical finding that may include seizures or developmental disabilities -- has historically not been collected in the same way.

Large initiatives to link genomic data with electronic medical records (EMR) are already underway to determine how existing genetic data can be linked to a lack of information about clinical outcomes. However, since these initiatives are relatively new, the role of EMRs in studying how disease-causing genetic changes can impact patients over longer periods of time has not been explored.

"Our study is the first example in childhood neurological orders to systematically connect genomic information with the medical records," says Ingo Helbig, MD, attending physician at CHOP's Epilepsy Neurogenetics Initiative (ENGIN), director of the genomic and data science core of ENGIN and lead investigator on this study. "This is really important as we need to understand the clinical features that children with genetic brain disorders, especially children with genetic epilepsies, develop over time. Using the technologies that we have developed, we can use the available data in the electronic medical records to bridge the gap between genetics and outcomes."

In this study, 62,104 patient encounters in 658 individuals with known or presumed genetic epilepsies were included. To standardize clinical observations, CHOP researchers utilized the Human Phenotype Ontology (HPO), a catalogue that provides a standardized format to characterize a patient's phenotypic features, including neurological findings, and allows for clinical information to be processed through data science techniques. This resulted in a total of 286,085 HPO terms, which were then grouped to 100 three-month time intervals, with the researchers assessing gene-phenotype associations at each interval.

The study team identified significant associations of various known genetic causes of epilepsy, including status epilepticus with the gene SCN1A at 1 year of age. Status epilepticus is a dangerous condition in which epileptic seizures last for more than five minutes or follow in short sequence without full recovery in between them. The study team also found an association between severe intellectual disability with the gene PURA at 10 years of age and infantile spasms with the gene STXBP1 at 6 months. These associations reflect known clinical features of each of these conditions that were identified through an automated analysis framework assessing more than 3,200 observational patient years, an amount of clinical data far beyond what could have been reviewed through manual chart review.

"With new precision therapies emerging, there is a pressing demand to understand the natural history of rare genetic epilepsies," said Sudha Kilaru Kessler, MD, a pediatric neurologist who is part of the leadership of CHOP's ENGIN and director of epilepsy surgery at CHOP's Pediatric Regional Epilepsy Program. "Electronic medical records are an untapped resource to learn about how very rare disorders present over time, which will allow us to include this information in our clinical practice. Finally, these tools will allow us to develop clinical decision support and learning health systems with the ultimate aim to improve the life of our patients."