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HOUSTON -- (April 30, 2020) -- Rice University researchers have discovered a hidden symmetry in the chemical kinetic equations scientists have long used to model and study many of the chemical processes essential for life.

The find has implications for drug design, genetics and biomedical research and is described in a study published this month in the Proceedings of the National Academy of Sciences. To illustrate the biological ramifications, study co-authors Oleg Igoshin, Anatoly Kolomeisky and Joel Mallory of Rice's Center for Theoretical Biological Physics (CTBP) used three wide-ranging examples: protein folding, enzyme catalysis and motor protein efficiency.

In each case, the researchers demonstrated that a simple mathematical ratio shows that the likelihood of errors is controlled by kinetics rather than thermodynamics.

"It could be a protein folding into the correct versus the incorrect conformation, an enzyme incorporating the right versus the wrong amino acid into the polypeptide chain, or a motor protein mistakenly stepping backward instead of going forward," said Igoshin, a CTBP investigator and professor of bioengineering at Rice. "All of those properties can be expressed as a ratio of two steady-state fluxes, and we found that biological properties expressed in these terms are under kinetic control."

The protein-folding example illustrates the implications for drug design. All proteins fold into a characteristic shape, and a fraction misfold into the wrong shape. Protein misfolding has been implicated in some heritable genetic disorders and diseases, and drugmakers are interested in making drugs that can reduce the chances of proteins misfolding.

Before it folds, a protein has energy, like a ball sitting atop a hill. Folding is the downhill run from this high-energy starting point to the place where the ball stops rolling. Chemists often use a visual aid called a "free-energy landscape" to chart energy levels in chemical reactions. The landscape looks like a mountain range with peaks and valleys, and the downhill run from a protein's unfolded starting point to its fully folded finishing point can look like a mountain road that winds through a series of valleys. Even if one town along the road is lower in elevation, a traveler might have to climb hills to get from one valley to the next on the way downhill.

"We've shown it's the barriers, the high points between valleys, that determine these ratios," Igoshin said. "The depths of the valleys don't matter.

"If you want to get a drug that will help a protein fold correctly, for example, our prediction is that the drug must be able to reduce a barrier along the folding pathway," he said. "If it only affects the valleys, say by improving the stability of some intermediate conformations along the folding pathway, it won't change the ratio of times the protein folds correctly versus incorrectly."

Igoshin said the work stemmed from a 2017 study where he, Kolomeisky and former CTBP postdoctoral researcher Kinshuk Banerjee showed that the accuracy of enzymatic catalysis was kinetically controlled. Igoshin described the discovery as a "kind of underlying symmetry of equations."

"If you look at the ratios of fluxes, you get this interesting cancellation, and all the terms that have to do with these values cancel out, and you get the invariance," he said. "When we first got this result, it seemed counterintuitive to us. Then, we were not sure if it was a coincidence, because in the previous paper we showed it for only two particular kinetic schemes. Now Joel's work has shown it can be generalized to this wide range of systems."

Igoshin said the symmetry "wasn't that hard to prove, but no one noticed it before."

"I think it is a very interesting physical result that has big implications in biology," he said. "It could help define the limits on what is possible in terms of controlling and optimizing system-level properties in many biological processes."

Scientists have been able to observe the universe and determine that about 80% of the its mass appears to be "dark matter," which exerts a gravitational pull but does not interact with light, and thus can't be seen with telescopes. Our current understanding of cosmology and nuclear physics suggests that dark matter could be made of axions, hypothetical particles with unusual symmetry properties.

In a new article published in Physical Review Letters and highlighted as an Editor's suggestion, ICFO researchers Pau Gomez, Ferran Martin, Chiara Mazzinghi, Daniel Benedicto Orenes, and Silvana Palacios, led by ICREA Prof. at ICFO Morgan W. Mitchell, report on how to search for axions using the unique properties of Bose-Einstein condensates (BECs).

The axion, if it exists, would imply "exotic spin-dependent forces." Magnetism, the best-known spin-dependent force, causes electrons to point their spins along the magnetic field, like a compass needle that points north. Magnetism is carried by virtual photons, whereas "exotic" spin-dependent forces would be carried by virtual axions (or axion-like particles). These forces would act on both electrons and nuclei, and would be produced not just by magnets, but also by ordinary matter. To know if axions do exist, a good way is to look and see if nuclei prefer to point toward other matter.

Several experiments are already searching for these forces, using "comagnetometers", which are paired magnetic sensors in the same place. By comparing the two sensors' signals, the effect of the ordinary magnetic field can be cancelled out, leaving just the effect of the new force. So far, comagnetometers have only been able to look for spin-dependent forces that reach about a meter or more. To look for short-range spin-dependent forces, a smaller comagnetometer is needed.

Bose Einstein Condensates (BECs) are gases cooled nearly to absolute zero. Because BECs are superfluid, their constituent atoms are free to rotate for several seconds without any friction, making them exceptionally sensitive to both magnetic fields and new exotic forces. A BEC is also very small, about 10 micrometers in size. To make a BEC comagnetometer, however, requires solving a tricky problem: how to put two BEC magnetometers in the same small volume.

In their study, Gomez and his colleagues report that they were able to solve this problem by using two different internal states of the same 87Rb BEC, each one acting as a separate but co-located magnetometer. The results of the experiment confirm the predicted high immunity to noise from the ordinary magnetic field and the ability to look for exotic forces with much shorter ranges than in previous experiments. Besides looking for axions, the technique may also improve precision measurements of ultracold collision physics and studies of quantum correlations in BECs.

Plastic pollution is an increasingly present threat to marine life and one which can potentially impact your dinner table.

Oysters, and other economically valuable shellfish, filter their food from the water where they may also inadvertently capture tiny microplastics. The ingestion and accumulation of these microplastics can have detrimental effects on their health and may be passed to other animals, including humans, through the food chain.

In a recent interdisciplinary study, University of Washington researchers at the School of Aquatic and Fishery Sciences, Department of Chemistry and Department of Materials Science and Engineering used advanced methodologies to accurately identify and catalog microplastics in Pacific oysters from the Salish Sea. They have discovered that the abundance of tiny microplastic contaminants in these oysters is much lower than previously thought. The findings were published in January in the journal Science of the Total Environment.

"Until now, not a lot of chemical analysis has been done on microplastics in oysters," said co-author Samantha Phan, a UW doctoral student in chemistry. "The microplastics that chemists have looked at in previous studies are slightly bigger and easy to visually recognize, but with oysters, the microplastics are much smaller and harder to identify."

In their study, the team sampled wild Pacific oysters harvested from Washington's state parks throughout the Salish Sea. Using standard processing methods, the oysters' tissue is dissolved and the remaining solution is passed through a filter. The filter collects all of the possible microplastic particles.

"Observation of filters is the method researchers have typically used, so if we had stopped there, we would have thought all the oysters had microplastics because small particles were present in most of the filters," said lead author Julieta Martinelli, a UW postdoctoral researcher at the School of Aquatic and Fishery Sciences.

Martinelli's initial observations under a dissecting microscope revealed what were thought to be high numbers of microplastics left behind in the testing filters, but when Phan further analyzed those filters with three advanced chemical identification techniques, they realized that most of what was left in the filters was not actually plastic.

"When we're characterizing plastics, or any polymers in chemistry in general, we have to use multiple techniques, and not every technique will give you a full picture. It's half a picture or just part of the picture," said Phan. "When you put all those pictures and characterizations together, you can have a more complete understanding of what the composition or identities of these particles are."

During their analyses, the team realized that many of the particles were, in fact, shell fragments, minerals, salts and even fibers from the testing filters themselves. In the end, they found that only about 2% of the particles distilled from the oysters could be confirmed as plastics.

"Most people so far have not used the combination of techniques or instruments that we used," said Martinelli. "It's really easy to stop at the first part and say, 'Oh, there's a lot of particles here. They look like plastic. They must be plastic.' But when you actually go deeper into the chemical composition, they might not be."

The number of plastic particles that the team found was relatively low compared to the total number of particles analyzed; however, they stress that while it appears Pacific oysters are not accumulating large amounts of plastic, they could not identify 40% of the particles observed due to technical limitations. The researchers also acknowledge that while using a combination of instruments is the most complete way to analyze these particles, access to the equipment, elevated costs and the extremely time-consuming nature of the work are limiting factors for widespread use.

As suspension feeders, oysters pull in water and the particles present in it when they inhale. Particles are then sorted in and out of the animal through their gills. Previous experiments have shown that when oysters are given microfibers or microbeads, they expel the majority of them either immediately or after a few hours. The hypothesis is that oysters' gill anatomy and physiology might be the reason why the team did not see large amounts of plastic accumulation in their samples.

"A lot of this has to do with how the oysters process water through their gills and how they get rid of particles," said Martinelli. "It doesn't mean microplastics are not in the water, it means that the animals are better at expelling them."

In agreement with this, it has been suggested that suspension feeding bivalves like oysters might not be good indicators of pollution in estuaries because they naturally expel microplastics instead of ingesting them, which is good news for consumers that like eating oysters.

WOODS HOLE, Mass. --The COVID-19 pandemic is a stark reminder that we move through a world shaped by unseen life. Bacteria, viruses, and other microscopic organisms regulate the Earth's vital functions and resources, from the air we breathe to all our food and most of our energy sources. An estimated one-third of the Earth's microbes are literally hidden, buried in sediments deep below the ocean floor. Now, scientists have shown that these "deep biosphere" microbes aren't staying put but are bubbling up to the ocean floor along with fluids from buried petroleum reservoirs. These hitchhikers in petroleum seeps are diversifying the microbial community that thrives at the seafloor, impacting deep-sea processes, such as carbon cycling, that have global implications.

"This study confirms that petroleum seeps are a conduit for transporting life from the deep biosphere to the seafloor," says co-author Emil Ruff, a scientist at the Marine Biological Laboratory (MBL), Woods Hole. The study, led by Anirban Chakraborty and Casey Hubert of the University of Calgary, is published this week in Proceedings of the National Academy of Sciences.

The team analyzed 172 seafloor sediment samples from the eastern Gulf of Mexico that had been collected as part of a 2011 survey for the oil industry. A fraction of these samples contained migrated gaseous hydrocarbons, the chief components of oil and gas. These petroleum seeps on the ocean floor harbored distinct microbial communities featuring bacteria and archaea that are well-known inhabitants of deep biosphere sediments.

"Whereas sedimentation slowly buries microbial communities into the deep biosphere, these results show that it's more of a two-way street. The microbes coming back up offer a window to life buried deeper below," Hubert says. "These relatively accessible surface sediments give us a glimpse into the vast, subsurface realm."

The study also adds a new dimension to understanding the metabolic diversity of seabed petroleum seep microbial communities. "If it weren't for the microbes living at hydrocarbon seeps, the oceans would be full of gas and oil," Chakraborty says.

Co-authors Bernie Bernard and James Brooks of TDI-Brooks International obtained the 172 Gulf of Mexico sediment cores and performed geochemical testing on them, setting the stage for microbiology testing at the University of Calgary.

"One of the strengths of this study is the large number of samples analyzed, allowing robust statistical inferences of the microbes present in the petroleum seeps," Ruff says. Because the seafloor is so difficult to access, explorations of deep-sea ecosystems are often limited by the number and quality of samples. The team used metagenomic approaches to determine what microbes were present in the sediment samples, and genome sequencing of particularly interesting organisms to indicate what their activity in the subsurface might be.

Army researchers predict quantum computer circuits that will no longer need extremely cold temperatures to function could become a reality after about a decade.

For years, solid-state quantum technology that operates at room temperature seemed remote. While the application of transparent crystals with optical nonlinearities had emerged as the most likely route to this milestone, the plausibility of such a system always remained in question.

Now, Army scientists have officially confirmed the validity of this approach. Dr. Kurt Jacobs, of the U.S. Army Combat Capabilities Development Command's Army Research Laboratory, working alongside Dr. Mikkel Heuck and Prof. Dirk Englund, of the Massachusetts Institute of Technology, became the first to demonstrate the feasibility of a quantum logic gate comprised of photonic circuits and optical crystals.

"If future devices that use quantum technologies will require cooling to very cold temperatures, then this will make them expensive, bulky, and power hungry," Heuck said. "Our research is aimed at developing future photonic circuits that will be able to manipulate the entanglement required for quantum devices at room temperature."

Quantum technology offers a range of future advances in computing, communications and remote sensing.

In order to accomplish any kind of task, traditional classical computers work with information that is fully determined. The information is stored in many bits, each of which can be on or off. A classical computer, when given an input specified by a number of bits, can process this input to produce an answer, which is also given as a number of bits. A classical computer processes one input at a time.

In contrast, quantum computers store information in qubits that can be in a strange state where they are both on and off at the same time. This allows a quantum computer to explore the answers to many inputs at the same time. While it cannot output all the answers at once, it can output relationships between these answers, which allows it to solve some problems much faster than a classical computer.

Unfortunately, one of the major drawbacks of quantum systems is the fragility of the strange states of the qubits. Most prospective hardware for quantum technology must be kept at extremely cold temperatures--close to zero kelvins--to prevent the special states being destroyed by interacting with the computer's environment.

"Any interaction that a qubit has with anything else in its environment will start to distort its quantum state," Jacobs said. "For example, if the environment is a gas of particles, then keeping it very cold keeps the gas molecules moving slowly, so they don't crash into the quantum circuits as much."

Researchers have directed various efforts to resolve this issue, but a definite solution is yet to be found. At the moment, photonic circuits that incorporate nonlinear optical crystals have presently emerged as the sole feasible route to quantum computing with solid-state systems at room temperatures.

"Photonic circuits are a bit like electrical circuits, except they manipulate light instead of electrical signals," Englund said. "For example, we can make channels in a transparent material that photons will travel down, a bit like electrical signals traveling along wires."

Unlike quantum systems that use ions or atoms to store information, quantum systems that use photons can bypass the cold temperature limitation. However, the photons must still interact with other photons to perform logic operations. This is where the nonlinear optical crystals come into play.

Researchers can engineer cavities in the crystals that temporarily trap photons inside. Through this method, the quantum system can establish two different possible states that a qubit can hold: a cavity with a photon (on) and a cavity without a photon (off). These qubits can then form quantum logic gates, which create the framework for the strange states.

In other words, researchers can use the indeterminate state of whether or not a photon is in a crystal cavity to represent a qubit. The logic gates act on two qubits together, and can create "quantum entanglement" between them. This entanglement is automatically generated in a quantum computer, and is required for quantum approaches to applications in sensing.

However, scientists based the idea to make quantum logic gates using nonlinear optical crystals entirely on speculation -- up until this point. While it showed immense promise, doubts remained as to whether this method could even lead to practical logic gates.

The application of nonlinear optical crystals had remained in question until researchers at the Army's lab and MIT presented a way to realize a quantum logic gate with this approach using established photonic circuit components.

"The problem was that if one has a photon travelling in a channel, the photon has a 'wave-packet' with a certain shape," Jacobs said. "For a quantum gate, you need the photon wave-packets to remain the same after the operation of the gate. Since nonlinearities distort wave-packets, the question was whether you could load the wave-packet into cavities, have them interact via a nonlinearity, and then emit the photons again so that they have the same wave-packets as they started with."

Once they designed the quantum logic gate, the researchers performed numerous computer simulations of the operation of the gate to demonstrate that it could, in theory, function appropriately. Actual construction of a quantum logic gate with this method will first require significant improvements in the quality of certain photonic components, researchers said.

"Based on the progress made over the last decade, we expect that it will take about ten years for the necessary improvements to be realized," Heuck said. "However, the process of loading and emitting a wave-packet without distortion is something that we should able to realize with current experimental technology, and so that is an experiment that we will be working on next."

Physical Review Letters published the team's findings in a peer-reviewed paper April 20.

Bethesda, MD (April 30, 2020) -- Changes to the gut microbiome interacted with the immune system to slow the growth of cancer in mice exposed to cigarette smoke, according to research that was selected for presentation at Digestive Disease Week® (DDW) 2020. DDW® data will be published in the May online supplements to Gastroenterology and GIE: Gastrointestinal Endoscopy.

"If the same relationship is found in human studies, treatments that modify the gut microbiome could improve cancer outcomes for smokers, who are susceptible to many cancers and fare worse in cancer treatment," said Prateek Sharma, MBBS, post-doctoral associate at University of Miami Miller School of Medicine, Florida, and a lead author in the study.

Previous studies have shown that the gut microbiome plays a role in the progression of cancer. To learn more about the specific relationship between smoking and the gut microbiome, researchers randomized mice into four groups: a control group getting only saline solution, a group receiving antibiotics alone to sterilize the gut, a smoking group pre-exposed for four weeks, and a group with both smoke exposure and antibiotics. All groups were injected with cancer cells. Cancer tumors were measured as the cigarette smoke exposure continued in the smoking groups for two months.

Researchers found that cigarette smoke exposure alone promoted tumor growth in all types of cancers tested -- colon, pancreatic and bladder. But when the gut microbiome was depleted with antibiotics in smoke-exposed mice, the cancer promoting effect of smoke disappeared. In fact, cancer growth in smoke-exposed mice with gut-clearing antibiotics was similar to the group with the slowest progressing cancers -- the mice with antibiotics and no smoke exposure.

The same experiment was conducted using mice that were genetically engineered to lack an adaptive immune response. In those mice, changes to the microbiome did not slow the cancer growth rate when exposed to smoke. This finding suggests that the interaction of the microbiome with the immune system influences cancer growth.

Future research could explore whether this relationship exists in human subjects and identify which specific "bad" bacteria in the gut of smokers have an impact on the immune system and cancer growth, Sharma said. This could involve eliminating bacteria with antibiotics or introducing specific bugs through probiotics or fecal microbial transplantation.

The research (abstract 439) was funded by James and Esther King Biomedical Research Program (9JK07), which is a state grant by the Florida Department of Health awarded to Vikas Dudeja, MD, associate professor of surgery at University of Miami Miller School of Medicine, who is the principal investigator of this study.

PITTSBURGH--Intelligent tutoring systems have been shown to be effective in helping to teach certain subjects, such as algebra or grammar, but creating these computerized systems is difficult and laborious. Now, researchers at Carnegie Mellon University have shown they can rapidly build them by, in effect, teaching the computer to teach.

Using a new method that employs artificial intelligence, a teacher can teach the computer by demonstrating several ways to solve problems in a topic, such as multicolumn addition, and correcting the computer if it responds incorrectly.

Notably, the computer system learns to not only solve the problems in the ways it was taught, but also to generalize to solve all other problems in the topic, and do so in ways that might differ from those of the teacher, said Daniel Weitekamp III, a Ph.D. student in CMU's Human-Computer Interaction Institute (HCII).

"A student might learn one way to do a problem and that would be sufficient," Weitekamp explained. "But a tutoring system needs to learn every kind of way to solve a problem." It needs to learn how to teach problem solving, not just how to solve problems.

That challenge has been a continuing problem for developers creating AI-based tutoring systems, said Ken Koedinger, professor of human-computer interaction and psychology. Intelligent tutoring systems are designed to continuously track student progress, provide next-step hints and pick practice problems that help students learn new skills.

When Koedinger and others began building the first intelligent tutors, they programmed production rules by hand -- a process, he said, that took about 200 hours of development for each hour of tutored instruction. Later, they would develop a shortcut, in which they would attempt to demonstrate all possible ways of solving a problem. That cut development time to 40 or 50 hours, he noted, but for many topics, it is practically impossible to demonstrate all possible solution paths for all possible problems, which reduces the shortcut's applicability.

The new method may enable a teacher to create a 30-minute lesson in about 30 minutes, which Koedinger termed "a grand vision" among developers of intelligent tutors.

"The only way to get to the full intelligent tutor up to now has been to write these AI rules," Koedinger said. "But now the system is writing those rules."

A paper describing the method, authored by Weitekamp, Koedinger and HCII System Scientist Erik Harpstead, was accepted by the Conference on Human Factors in Computing Systems (CHI 2020), which was scheduled for this month but canceled due to the COVID-19 pandemic. The paper has now been published in the conference proceedings in the Association for Computing Machinery's Digital Library.

The new method makes use of a machine learning program that simulates how students learn. Weitekamp developed a teaching interface for this machine learning engine that is user friendly and employs a "show-and-correct" process that's much easier than programming.

For the CHI paper, the authors demonstrated their method on the topic of multicolumn addition, but the underlying machine learning engine has been shown to work for a variety of subjects, including equation solving, fraction addition, chemistry, English grammar and science experiment environments.

The method not only speeds the development of intelligent tutors, but promises to make it possible for teachers, rather than AI programmers, to build their own computerized lessons. Some teachers, for instance, have their own preferences on how addition is taught, or which form of notation to use in chemistry. The new interface could increase the adoption of intelligent tutors by enabling teachers to create the homework assignments they prefer for the AI tutor, Koedinger said.

Enabling teachers to build their own systems also could lead to deeper insights into learning, he added. The authoring process may help them recognize trouble spots for students that, as experts, they don't themselves encounter.

"The machine learning system often stumbles in the same places that students do," Koedinger explained. "As you're teaching the computer, we can imagine a teacher may get new insights about what's hard to learn because the machine has trouble learning it."

Reproduction can be risky. In the case of katydids, some hunting bats eavesdrop on male mating calls to locate the insects, but little is known about the risk to mates as they move toward each other. A recent study by scientists at the Smithsonian Tropical Research Institute (STRI) and collaborating institutions explores the hunting behavior of a Neotropical bat, asking whether prey movement adds to the risk that they will be eaten.

Inga Geipel, a Tupper postdoctoral fellow at STRI and one of the lead authors on the study, and her colleagues, observed the predation behavior of Micronycteris microtis, a gleaning bat species that loves to eat katydids, as it responded to different prey behavior. Common in Central and South America, M. microtis can detect silent and motionless prey through echolocation alone.

“I previously showed the surprising ability of M. microtis to find motionless prey and explained how they do it,” Geipel said. “But I kept wondering whether movement would actually increase the risk that an insect would be found.”
“From graduate student Ciara Kernan and Hannah ter Hofstede, Dartmouth assistant professor and STRI research associate, both experts on insect communication, I learned more about the way that katydids use vibrational signals during courtship,” Geipel said. “Also, the mates need to move toward each other, creating an inevitable cue that could be picked up by a predator using echolocation.”

Alongside Ciara Kernan and STRI intern Amber Litterer, Geipel placed bats in a flight cage and used models that simulated motionless, vibrating or walking katydids. The experiment showed that M. microtis preferred walking katydid models to still or vibrating ones. They also chose vibrating models over motionless prey and scanned moving prey for longer periods of time.

“Our study suggests that not only signalers, but also searchers may be at risk,” Geipel said. “Both male and female katydids are prone to predation during a courtship interaction as they move toward each other.”

For the team, this finding also opens new avenues for future research, as researchers explore yet new prey-finding strategies of gleaning bats and predator avoidance schemes of Neotropical katydids.

“Bats are such key players in our ecosystems, playing critical roles as pollinators, seed dispersers and forest regenerators,” said Rachel Page, STRI staff scientist and co-author. “And one of their most important roles is insect control. Here we see that bats are even more effective insect hunters than we previously knew. Not only can they effectively pick herbivorous insects off of leaves in the cluttered understory of the rainforest at night, they can successfully attend even to very small movements, placing yet more pressure on the courtship behavior of their katydid prey.”

A plant extract combination of fruits, leaves, and roots may help to relieve hangover symptoms, reveals research published online in BMJ Nutrition Prevention & Health.

And received wisdom that it's the dehydrating effects of alcohol and the associated loss of electrolytes--electrically charged minerals in the body that help balance water content and acid levels--which are largely responsible for some of the most common hangover symptoms, may be wrong, the findings indicate.

Various natural remedies have been recommended to ease hangover symptoms, but there is as yet no strong scientific evidence for their use.

In a bid to address that, the researchers assessed the potential of specific plant extracts, vitamins and minerals, and antioxidant compounds to ease a range of recognised physical and psychological symptoms associated with drinking alcohol.

The plant extracts included Barbados cherry (Acerola), prickly pear, ginkgo biloba, willow and ginger root. The vitamins and minerals included magnesium, potassium, sodium bicarbonate, zinc, riboflavin, thiamin and folic acid.

Some 214 healthy 18-65 year olds were randomly split into three groups and given a 7.5 g flavoured, water soluble supplement 45 minutes before, and immediately after they stopped drinking any of beer, white wine, or white wine spritzer.

The first group (69) were given a supplement containing the plant extracts, vitamins and minerals, and additional antioxidant compounds--steviol glycosides and inulin. The second group (76) were given a supplement minus the plant extracts, while the third group (69) were given glucose alone (placebo).

The number and type of drinks consumed was recorded as was how many times they emptied their bladder between 1700 and 2100 hours.

Blood and urine samples and blood pressure measurements were taken before and after the start of this four-hour period, after which the participants were sent home to sober up.

Twelve hours later the same samples and blood pressure measurements were taken, and participants filled in a questionnaire about the type and intensity of perceived hangover symptoms, which were ranked on a zero to 10 scale.

The average amount of alcohol consumed was virtually the same in all three groups: 0.62 ml/minute.

Analysis of all the data showed that symptom intensity varied widely among the participants.

But compared with the glucose only supplement, those taking the full supplement of plant extracts, minerals/vitamins, and antioxidants reported less severe symptoms.

Average headache intensity was 34% less, nausea 42% less, while feelings of indifference fell by an average of 27% and restlessness by 41%. No significant differences or reductions were reported for any of the other symptoms.

Polyphenol and flavonoid compounds in each of the five plant extracts have been associated with curbing the physiological impact of alcohol in previously published experimental studies, explain the researchers. But it's not clear how.

"The underlying mechanisms remain to be unravelled and surely need further investigation," they suggest.

No significant difference in any symptom was reported by those taking the supplement minus the plant extracts, suggesting that plant extracts were largely responsible for the observed changes, say the researchers.

And the absence of any observed impact for vitamins and minerals on their own suggests that alcohol might not affect electrolyte and mineral balance, as is commonly thought, they add.

Their analysis also showed levels of water content in the body weren't significantly associated with the amount of alcohol drunk. "Our results suggest that alcohol-induced increased fluid excretion does not necessarily lead to a significant dehydration process," they write.

"It seems to be clear that hangover symptoms are predominantly caused by alcohol and its metabolites," they conclude.

A new study shows the cost of cancer care for Syrian refugees in host nations for the first time, as researchers urge resources to be provided in the wake of the COVID-19 pandemic.

The study published today in the Lancet Oncology, led by researchers at King's College London and a collaboration between the cancer and palliative care working group within UKRI Global Challenge Research Fund R4HC-MENA programme (r4hc-mena.org), shows the increasing cost of cancer care for refugees on host nations such as Turkey, Lebanon and Jordan.

The findings come as humanitarian organisations and host countries are reallocating funding away from cancer in response to the COVID-19 pandemic.

Professor Richard Sullivan from King's College London said: "The consequences of regional lockdowns and the re-allocation of funding away from non-communicable diseases to COVID-19 will lead to serious loss of life and suffering in refugee populations from cancer in the next three years. There is a critical need for UN and bilateral funders such as the UK to ensure balance in support that recognises the growing impact of cancer in these refugee populations."

Although host countries can apply for funding to meet healthcare costs for their refugee communities, it had not been known how much is needed to meet the costs.

The study, which is the first of its kind to examine the economic burden of cancer in Syrian refugee populations, a major health problem, estimates that it would cost only around 3,000 to 7,000 euros per cancer case to provide good quality care.

This amounts to 11% of the current annual budget of $345 million requested for healthcare costs of Syrian refugees in 2017 for Jordan, Lebanon, and Turkey. The findings should give governments and international agencies a better understanding of resources for the Syrian refugees with cancer to continue providing funding for cancer care even during the COVID-19 pandemic.

Prof. Dr. Tezer Kutluk UICC Past-president and Chair, Department of Pediatrics, Cancer Institute and Faculty of Medicine, Hacettepe University, Ankara, Turkey, said:

"How to use the limited resources is a major challenge on managing the refugee crisis. Better understanding the economic burden of cancer care will help governments, international agencies and all stakeholders to better use of available resources for the cancer care of refugee population. This population based modeling study is a good example of estimating the financial burden and hope it will stimulate other researches on health economics for refugee population"

Dr Deborah Mukherji, Associate Professor of Clinical Medicine, Division of Hematology Oncology, American University of Beirut, said: "The COVID-19 pandemic has focussed attention on the fact that health inequalities impact society as a whole. As humanitarian response to crisis becomes prolonged, this article highlights the need for accurate data to inform policy and manage limited resources while protecting vulnerable populations. With multiple stakeholders and competing priorities, cancer care in refugees has not been the focus of sufficient data collection or funding. Strengthening regional capacity for cancer registration, cancer control and context-specific management guidelines will be essential to mitigate the growing burden of cancer in conflict-affected populations of the Middle East."

Dr Julie Torode, Director, Special Projects, Union of International Cancer Control, said: "The pressing need for integrated models of care for refugees with cancer is heavily underscored as health systems struggle to respond to the COVID-19 pandemic and the consequences of lockdown and closed borders. Sustainable, inclusive and comprehensive financing mechanisms will support steps towards universal health coverage in host countries, like Jordan, Lebanon and Turkey and speed the recovery phase for cancer services and ensure that no one is left behind."

HRH Princess Dina Mired, Princess of Jordan, and current President of the Union of International Cancer Control a major partner of R4HC-MENA programme, said: "The pressing need for integrated models of care for refugees with cancer is heavily underscored as health systems struggle to respond to the COVID-19 pandemic and the consequences of lockdown and closed borders. Sustainable, inclusive and comprehensive financing mechanisms will support steps towards universal health coverage in host countries, like Jordan, Lebanon and Turkey and speed the recovery phase for cancer services and ensure that no one is left behind."

A discovery that long eluded physicists has been detected in a laboratory at Princeton. A team of physicists detected superconducting currents -- the flow of electrons without wasting energy -- along the exterior edge of a superconducting material. The finding was published in the May 1 issue of the journal Science.

The superconductor that the researchers studied is also a topological semi-metal, a material that comes with its own unusual electronic properties. The finding suggests ways to unlock a new era of "topological superconductivity" that could have value for quantum computing.

"To our knowledge, this is the first observation of an edge supercurrent in any superconductor," said Nai Phuan Ong, Princeton's Eugene Higgins Professor of Physics and the senior author on the study.

"Our motivating question was, What happens when the interior of the material is not an insulator but a superconductor?" Ong said. "What novel features arise when superconductivity occurs in a topological material?"

Although conventional superconductors already enjoy widespread usage in magnetic resonance imaging (MRI) and long-distance transmission lines, new types of superconductivity could unleash the ability to move beyond the limitations of our familiar technologies.

Researchers at Princeton and elsewhere have been exploring the connections between superconductivity and topological insulators -- materials whose non-conformist electronic behaviors were the subject of the 2016 Nobel Prize in Physics for F. Duncan Haldane, Princeton's Sherman Fairchild University Professor of Physics.

Topological insulators are crystals that have an insulating interior and a conducting surface, like a brownie wrapped in tin foil. In conducting materials, electrons can hop from atom to atom, allowing electric current to flow. Insulators are materials in which the electrons are stuck and cannot move. Yet curiously, topological insulators allow the movement of electrons on their surface but not in their interior.

To explore superconductivity in topological materials, the researchers turned to a crystalline material called molybdenum ditelluride, which has topological properties and is also a superconductor once the temperature dips below a frigid 100 milliKelvin, which is -459 degrees Fahrenheit.

"Most of the experiments done so far have involved trying to 'inject' superconductivity into topological materials by putting the one material in close proximity to the other," said Stephan Kim, a graduate student in electrical engineering, who conducted many of the experiments. "What is different about our measurement is we did not inject superconductivity and yet we were able to show the signatures of edge states."

The team first grew crystals in the laboratory and then cooled them down to a temperature where superconductivity occurs. They then applied a weak magnetic field while measuring the current flow through the crystal. They observed that a quantity called the critical current displays oscillations, which appear as a saw-tooth pattern, as the magnetic field is increased.

Both the height of the oscillations and the frequency of the oscillations fit with predictions of how these fluctuations arise from the quantum behavior of electrons confined to the edges of the materials.

Researchers have long known that superconductivity arises when electrons, which normally move about randomly, bind into twos to form Cooper pairs, which in a sense dance to the same beat. "A rough analogy is a billion couples executing the same tightly scripted dance choreography," Ong said.

The script the electrons are following is called the superconductor's wave function, which may be regarded roughly as a ribbon stretched along the length of the superconducting wire, Ong said. A slight twist of the wave function compels all Cooper pairs in a long wire to move with the same velocity as a "superfluid" -- in other words acting like a single collection rather than like individual particles -- that flows without producing heating.

If there are no twists along the ribbon, Ong said, all Cooper pairs are stationary and no current flows. If the researchers expose the superconductor to a weak magnetic field, this adds an additional contribution to the twisting that the researchers call the magnetic flux, which, for very small particles such as electrons, follows the rules of quantum mechanics.

The researchers anticipated that these two contributors to the number of twists, the superfluid velocity and the magnetic flux, work together to maintain the number of twists as an exact integer, a whole number such as 2, 3 or 4 rather than a 3.2 or a 3.7. They predicted that as the magnetic flux increases smoothly, the superfluid velocity would increase in a saw-tooth pattern as the superfluid velocity adjusts to cancel the extra .2 or add .3 to get an exact number of twists.

The team measured the superfluid current as they varied the magnetic flux and found that indeed the saw-tooth pattern was visible.

In molybdenum ditelluride and other so-called Weyl semimetals, this Cooper-pairing of electrons in the bulk appears to induce a similar pairing on the edges.

The researchers noted that the reason why the edge supercurrent remains independent of the bulk supercurrent is currently not well understood. Ong compared the electrons moving collectively, also called condensates, to puddles of liquid.

"From classical expectations, one would expect two fluid puddles that are in direct contact to merge into one," Ong said. "Yet the experiment shows that the edge condensates remain distinct from that in the bulk of the crystal."

The research team speculates that the mechanism that keeps the two condensates from mixing is the topological protection inherited from the protected edge states in molybdenum ditelluride. The group hopes to apply the same experimental technique to search for edge supercurrents in other unconventional superconductors.

"There are probably scores of them out there," Ong said.

Boulder, Colo., USA: Buried a mile beneath Greenland's thick ice sheet is a network of canyons so deep and long that the largest of these has been called Greenland's "Grand Canyon." This megacanyon's shape suggests it was carved by running water prior to widespread glaciation, but exactly when and how the island's grandest canyon formed are topics of intense debate.

Now scientists from the U.S. and Denmark are proposing a surprising new hypothesis for the megacanyon's formation: catastrophic "outburst" floods that suddenly and repeatedly drained large meltwater-filled lakes. The findings, published this week in the journal Geology, also suggest that Greenland's subglacial canyon network has influenced the island's ice sheet since its inception.

Although repeated outburst floods have been suggested as the mechanism by which the Columbia River and other North America canyon networks formed, they had not previously been considered as the source of the remarkable landscape hidden beneath the Greenland Ice Sheet, says Benjamin Keisling, the study's lead author and a former graduate student at the University of the Massachusetts, who also collaborated with researchers at Denmark's Centre for Ice and Climate during a National Science Foundation GROW fellowship.

"If the floods we propose occurred, they could have influenced ocean circulation, causing abrupt climate changes with regional and perhaps global significance," says Keisling, now a postdoctoral fellow at Lamont-Doherty Earth Observatory. "The megacanyon beneath northern Greenland also influences how ice and water flow in the subglacial environment today, which affects present-day ice-sheet stability," he says.

A Different Approach

In most studies of Greenland, researchers use the modern ice sheet as a starting point for understanding how it has changed over time. But for this study, Keisling and his co-authors decided on a different approach: investigating what Greenland looked like prior to widespread glaciation. "We wanted to better understand the dynamics of 'glacial inception'--how, where, and why the ice sheet first grew on an ice-free island," he says.

The team also wanted to gain insights into how the ice sheet grew back after melting. "We know from prior work this has happened multiple times in the past and could again in the future, given enough global warming," says Keisling.

The researchers used coupled ice-sheet and climate models to simulate the Greenland Ice Sheet's evolution over multiple glacial-interglacial cycles during the global cooling from the Pliocene into the Pleistocene, 2.58 million years ago. They found that following long periods with stable temperatures, an exceptionally warm period could cause the ice sheet to retreat rapidly. This melting led to the development of large, ice-dammed lakes in areas where the bedrock was still depressed due to the former ice sheet's weight.

The simulations eventually show the ice dams give way, leading to large outburst floods. "Over time," says Keisling, "it appears that the filling and draining of these lakes as the ice repeatedly retreated and advanced carved Greenland's megacanyons." Similar floods have been documented at the edge of other retreating ice sheets, he says.

Ice-Sheet Stability: Past, Present, and Future

Based on comparisons with modern outburst floods, the researchers estimate that it took tens to hundreds of these events to carve Greenland's largest canyon. According to Keisling, widespread sediment deposition in the water-filled basins may have also impacted the ice sheet's behavior each time it grew back.

Ultimately, Keisling says, the study results point to testable hypotheses that can guide future research to finally settle the ongoing debate about whether the Greenland Ice Sheet's stability has changed over time. "Knowing the history of Greenland's bedrock provides context for understanding the ice sheet's long-term behavior," he says. "This helps paint a picture of what happened during past warm periods when the melting ice sheet caused global sea levels to rise--a phenomenon we are also seeing today."

The next time a tick feeds on you, Washington State University researchers hope to make sure persistent arthritis caused by Lyme disease doesn't linger for a lifetime.

Troy Bankhead, associate professor in WSU's Veterinary Microbiology and Pathology department, and his team have spent more than a decade analyzing an immune evasive protein of Borrelia burgdorferi, the bacterium that causes tick-borne Lyme disease.

With the lab's latest finding, that work is beginning to pay off.

According to research recently published in Cell Reports, Bankhead and assistant research professor Abdul Lone discovered that a surface protein known as VlsE acts as a shield to prevent the immune system from effectively fighting the disease. In particular, the study examined how VlsE protects one of the main proteins responsible for Lyme disease's persistent arthritis.

"This really has a significant impact in the development of vaccines," Bankhead said. "If we can determine which proteins are shielded as opposed to which ones are not, then of course those that are not protected are going to be better candidates for a vaccine."

The Centers for Disease Control and Prevention estimates some 300,000 people may get Lyme disease each year in the United States alone. It is most prevalent in the northeast.

If not treated early with antibiotics, Lyme disease can cause lifelong arthritis, and in more severe cases, bladder infections, heart inflammation, and neurologic and cognitive issues like loss of memory and balance.

"We chose the arthritis-related protein because arthritis is the most common symptom you see in North America," Lone said.

By engineering a strain of Borrelia burgdorferi in the lab without the surface lipoprotein VlsE, they were able to confirm it was protecting the arthritis-related protein from an antibody response.

Bankhead and Lone tested the new Borrelia strain in mice and found the animals were more easily able to clear the infection.

Then, Bankhead and Lone confirmed that the new Borrelia strain was susceptible to antibodies under the microscope.

By using fluorescence microscopy, a process that uses energy from electrons to emit light under a microscope, Bankhead and Lone watched as antibodies were unable to bind to the protein responsible for Lyme's persistent arthritis when the VlsE protein was present.

When the VlsE protein was removed, antibodies were able to recognize and bind to the arthritis-related protein.
"When you don't have VlsE those bacteria light up and that is because those antibodies are able to bind and recognize that arthritis-related protein in the absence of that VlsE shield," Bankhead said. "That's exactly what we were seeing."

Understanding the VlsE protein is acting as a shield for the bacterium's arthritic-causing protein is significant for vaccine development and future research. While it is unknown if other surface proteins are protected, Bankhead said it is likely. He noted the scientific community is gaining ground on understanding these proteins but producing any vaccine is well into the future.

Still, the finding creates two avenues for researchers to eliminate Lyme disease: take down the VlsE shield, or, find a way for the antibody response to get in front of the ever-adapting bacterium and eliminate it.

"HIV/AIDS persists for years in human beings. The same thing happens with Borrelia, it persists," Lone said. "While this finding tells us a lot about Borrelia. Our next step is to understand how it persists. Once we understand the mechanism of persistence, we can eliminate the disease."

New Rochelle, NY, April 30, 2020--A new study of medical staff treating COVID-19-infected patients found 42.8% experienced serious skin injury related to the use of personal protective equipment (PPE), including masks, goggles, face shields, and protective gowns. Researchers concluded that the skin injuries put staff at increased risk of infection, with insufficient prevention and treatment measures in place, according to the study published in Advances in Wound Care, a monthly peer-reviewed journal from Mary Ann Liebert, Inc., publishers. Click here to read the full-text article free on the Advances in Wound Care website through May 30, 2020.

The article entitled "The Prevalence, Characteristics and Prevention Status of Skin Injury Caused by Personal Protective Equipment Among Medical Staff in Fighting COVID-19: A Multi-Center, Cross-Sectional Study" was coauthored by Qixia Jiang, Nanjing University School of Medicine (Nanjing, China) and a large team of Chinese clinicians. The researchers identified three main types of PPE-related skin injuries: device-related pressure injuries; moist associated skin damage; skin tear. Several factors increased the risk for skin injury: heavy sweating, greater daily wearing time, being male, and using grade 3 versus grade 2 PPE.

"These significant findings are consistent with independent observations in Europe and United States, and call for systematic studies addressing skin injury and repair in COVID-19+ patients as well as in their healthcare providers," says Editor-in-Chief Chandan K. Sen, PhD, Distinguished Professor at the Indiana University School of Medicine and Executive Director of Indiana University Health Comprehensive Wound Center, Indianapolis, IN.

College Park, Md. -- Scientists in the University of Maryland (UMD)'s Department of Materials Science and Engineering (MSE) have reinvented a 26,000-year-old manufacturing process into an innovative approach to fabricating ceramic materials that has promising applications for solid-state batteries, fuel cells, 3D printing technologies, and beyond.

Ceramics are widely used in batteries, electronics, and extreme environments--but conventional ceramic sintering (part of the firing process used in the manufacture of ceramic objects) often requires hours of processing time. To overcome this challenge, a Maryland research team has invented an ultrafast high-temperature sintering method that both meets the needs of modern ceramics and fosters the discovery of new material innovations.

The study, led by Liangbing Hu, Herbert Rabin Distinguished Professor of the A. James Clark School of Engineering and director of the Center for Materials Innovation at UMD, was published on the May 1 cover of Science. Chengwei Wang, an assistant research scientist in Hu's group, served as first author on the study.

Conventional sintering techniques require a long processing time--it takes hours for a furnace to heat up, then several hours more to 'bake' the ceramic material--which is particularly problematic in the development of electrolytes for solid-state batteries. Alternative sintering technologies (such as microwave-assisted sintering, spark plasma sintering, and flash sintering) are limited for a variety of reasons, often because they are material-specific and/or expensive.

The Maryland team's new method of ultrafast high-temperature sintering offers high heating and high cooling rates, an even temperature distribution, and sintering temperatures of up to 3,000 degrees Celsius. Combined, these processes require less than 10 seconds of total processing time--more than 1,000 times faster than the traditional furnace approach of sintering.

"With this invention, we 'sandwiched' a pressed green pellet of ceramic precursor powders between two strips of carbon that quickly heated the pellet through radiation and conduction, creating a consistent high-temperature environment that forced the ceramic powder to solidify quickly," Hu said. "The temperature is high enough to sinter basically any ceramic material. This patented process can be extended to other membranes beyond ceramics."

The study was conducted through close collaboration with Yifei Mo (associate professor, UMD), J.C Zhao (professor and department chair, UMD), Howard Wang (visiting research professor, UMD), Jian Luo (professor, UC San Diego), Xiaoyu Zheng (assistant professor, UCLA), and Bruce Dunn (professor and department chair, UCLA).

"Ultrafast high-temperature sintering represents a breakthrough in ultrafast sintering technologies, not only because of its general applicability to a broad range of functional materials, but also due to a great potential of creating non-equilibrium bulk materials via retaining or generating extra defects," said Luo.

The rapid sintering technology is being commercialized through HighT-Tech LLC, a UMD spinoff company with a focus on a range of high temperature technologies (http://www.highT-Tech.com).

More about this research:

"This new method solves the key bottleneck problem in computation and AI-guided materials discovery," said Mo. "We've enabled a new paradigm for materials discovery with an unprecedented accelerated pace."

"We are delighted to see the pyrolysis time reduced from tens of hours to a few seconds, preserving the fine 3D-printed structures after fast sintering," Zheng said.