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Philadelphia, August 3, 2020 - In a new study, investigators report that patients undergoing atrial fibrillation (AF) ablation, who are physically fit before the procedure, have a much higher chance of benefiting from the procedure and remaining in normal sinus rhythm. Less fit patients are rehospitalized more often, continue to use antiarrhythmic therapies longer, and have higher death rates than fitter patients. Their results appear in Heart Rhythm, the official journal of the Heart Rhythm Society, the Cardiac Electrophysiology Society, and the Pediatric & Congenital Electrophysiology Society, published by Elsevier.

AF has reached epidemic proportions globally. Previous studies have documented impressive reductions in AF recurrence after lifestyle modifications, exercise, and weight loss surgery. Although cardiorespiratory fitness (CRF) has been shown to predict AF and arrhythmia recurrence in patients with AF, this is the first study to look at the effect CRF has on patient outcomes after ablation.

"AF does not occur in a vacuum but rather represents one manifestation of the impact of poor physical fitness and related risk factors including hypertension, obesity, diabetes, and others," explained lead investigator Wael A. Jaber, MD, Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH, USA.

The study included 591 patients who underwent their first AF ablation at Cleveland Clinic between 2012 and 2018 and had undergone treadmill stress testing within 12 months prior to the procedure. Patient characteristics such as age, gender, and body mass were obtained from medical records, as was information about other medical conditions such as hypertension, diabetes, congestive heart failure, coronary artery disease, and sleep apnea. Investigators ranked patients' fitness as low, adequate, or high according to standard models based on metabolic equivalents (METS), which measure energy expenditure for physical activities.

Patients were monitored for recurrence of AF for an initial three months after ablation. If they experienced AF symptoms during this period, monitoring continued for an additional three months.

Over 32 months after ablation, recurrent AF was observed in 271 patients. In the low CRF group 120 (79 percent) developed recurrent arrhythmia compared to 62 (54 percent) in the adequate, and 89 (27.5 percent) in the high CRF groups. The investigators also divided the patients into 10 groups based on the percentage of METS expended during the stress test and found that as CRF increased, recurrent arrhythmia decreased.

Investigators found other benefits as well. Antiarrhythmic medication was discontinued in 56 percent of patients in the high CRF group compared to 11 percent in the low CRF group. Only 18.5 percent of the high CRF group required rehospitalization versus 60.5 percent in the low group.

Thirty patients in the study group died: 11 percent of the low CRF group versus 4 percent and 2.5 percent in the adequate and high CRF groups, respectively. Notably, comorbidities such as hypertension, diabetes, and obstructive sleep apnea were similar across all three groups.

"High physical fitness can keep you in rhythm after AF ablation," commented Dr. Jaber. "Being fit is a great antiarrhythmic. Our findings indicate that being physically fit acted almost like a medication in a dose response fashion where there was a gradual and sustained success in 'staying in rhythm.'"

Routine assessment of CRF prior to AF ablation might serve as a clinical tool informing healthcare providers as well as patients about the odds for success and maintaining long term sinus rhythm.

"Higher CRF can be seen as another target to meet, similar to blood pressure control, glycemic control, and weight loss. In patients who are less fit, we need to study whether a preprocedural cardiac rehabilitation program may alter and improve the chances of success of AF ablation," noted Dr. Jaber.

In an accompanying editorial, Eric Black-Maier, MD, and Jonathan P. Piccini, Sr., MD, MHS, FHRS, Duke Center for Atrial Fibrillation & Electrophysiology Section, Duke University Medical Center, Durham, NC, USA, observed that while CRF is clearly a risk marker, clinical trials are needed to determine whether modifying CRF prior to ablation can improve outcomes.

"Over the last 50 years, our understanding of CRF, exercise capacity, and arrhythmia occurrence in patients with AF continues to evolve," they noted. "The data in this study clearly demonstrate that arrhythmia-free survival is indeed survival of the fittest. Time will tell if exercise training and improvements in CRF can change outcomes after ablation."

When humans bring a non-native herbivore to an isolated island, the native trees do not possess traits to craft an operative defense to the new threat, and the results can be devastating. A long-term study on cycads in Guam has revealed how rapidly invasive species devastated the native Cycas micronesica species and the key factors that have influenced the plant's mortality. The research -- conducted by the Western Pacific Tropical Research Center at the University of Guam and the College of Micronesia-FSM -- is published in the May 2020 issue of Diversity, a peer-reviewed journal published by MDPI.

"Guam's Cycas micronesica was the most abundant tree on Guam two decades ago, but then an onslaught of non-native insect herbivores invaded the island and initiated sweeping mortality," said Adrian Ares, associate director of the Western Pacific Tropical Research Center, where the research was conducted.

The researchers established 120 permanent plots throughout Guam in 2005 during the time period that the armored scale Aulacaspis yasumatsui was spreading across the island from the initial 2003 infestation site. This tiny insect was among the first to invade Guam and remains the most devastating cycad pest that has altered the island's natural and urban forests. As the plots were being positioned to provide the pre-invasion plant data, a second invasion occurred -- the specialist butterfly Chilades pandava. The larvae of this butterfly consume vast quantities of young tender cycad leaf tissue.

The results of the researchers' island-wide compilation of plant mortality over 15 years reveals only 4% of the 2005 population remains alive on Guam.

The 15-year data set validated an earlier observation that plant size was negatively correlated with speed of mortality. The first wave of mortality included seedlings -- 100% of which were killed by 2006 -- and the second wave of mortality encompassed juvenile plants, 100% of which were killed by 2014. The persisting populations are comprised of large individuals that possessed substantial stored resources when the non-native pests initiated the threats.

"The means by which the invasion of an island by a non-native herbivore can wreak such havoc is actually two-fold," said Murukesan V. Krishnapillai, one of the authors of the study. "First, the native tree that is attacked by the new pest has spent millennia evolving without a comparable herbivore and, therefore, possesses few defensive strategies. Second, the pest has escaped from its own native habitat where it co-evolved with natural enemies, and, therefore, the new island environment contains no natural enemies to tamp down the pests' population growth."

The Guam team used what biologists call a Type 1 right-censoring approach to document the plant mortality and joined the College of Micronesia in the Federated States of Micronesia to showcase the forests on the Micronesian island of Yap as an unthreatened healthy population of the same tree species.

The team's research on Guam and within the native geographic range of these two pests indicate the armored scale's threats are due to the release from the natural enemies in its homeland, and the butterfly's threats are caused by the absence of defensive strategies by the tree.

The study also illuminated two other spatial factors that have influenced the plant population's responses to the non-native insect herbivore threats. First, the populations in Western localities have exhibited much more mortality than the populations in Eastern localities. Second, the plants within large contiguous forests have exhibited less damage than plants within forest fragments.

The authors contend that this sort of information is important for informing the factors that influence localized loss of genes of endangered tree species.

"Conservationists need developing knowledge like this to craft the most appropriate mitigation strategies and identify where available funds should be spent," Ares said.

The long-term nature of the study, which Ares said is rare in contemporary academia, and the use of benchmarking were crucial in developing a full understanding of rapidly developing threats to island tree populations. The decision to establish permanent plots throughout Guam prior to the onset of the predicted damage from the non-native pests has proven to be crucial for understanding the 15 years of damage.

The study concluded that the only high priority activity to conserve the Cycas micronesica species in Guam is to establish a complex integrated biological control program under the direction of scientists with international expertise. The report says that knowing that plant size and habitat traits influence cycad susceptibility to non-native threats can now inform conservation management decisions.

The fields of condensed matter physics and material science are intimately linked because new physics is often discovered in materials with special arrangements of atoms. Crystals, which have repeating units of atoms in space, can have special patterns which result in exotic physical properties. Particularly exciting are materials which host multiple types of exotic properties because they give scientists the opportunity to study how those properties interact with and influence each other. The combinations can give rise to unexpected phenomena and fuel years of basic and technological research.

In a new study published in Science Advances this week, an international team of scientists from the USA, Columbia, Czech Republic, England, and led by Dr. Mazhar N. Ali at the Max Planck Institute of Microstructure Physics in Germany, has shown that a new material, KV3Sb5, has a never-seen-before combination of properties that results in one of the largest anomalous Hall effects (AHEs) ever observed; 15,500 siemens per centimeter at 2 Kelvin.

Discovered in the lab of co-author Prof. Eric Toberer at the Colorado School of Mines, KV3Sb5 combines four properties into one material: Dirac physics, metallic frustrated magnetism, 2D exfoliability (like graphene), and chemical stability.

Dirac physics, in this context, relates to the fact that the electrons in KV3Sb5 aren't just your normal run-of-the-mill electrons; they are moving extremely fast with very low effective mass. This means that they are acting "light-like"; their velocities are becoming comparable to the speed of light and they are behaving as though they have only a small fraction of the mass which they should have. This results in the material being highly metallic and was first shown in graphene about 15 years ago.

The "frustrated magnetism" arises when the magnetic moments in a material (imagine little bar magnets which try to turn each other and line up North to South when you bring them together) are arranged in special geometries, like triangular nets. This scenario can make it hard for the bar magnets to line up in way that they all cancel each other out and are stable. Materials exhibiting this property are rare, especially metallic ones. Most frustrated magnet materials are electrical insulators, meaning that their electrons are immobile. "Metallic frustrated magnets have been highly sought after for several decades. They have been predicted to house unconventional superconductivity, Majorana fermions, be useful for quantum computing, and more," commented Dr. Ali.

Structurally, KV3Sb5 has a 2D, layered structure where triangular vanadium and antimony layers loosely stack on top of potassium layers. This allowed the authors to simply use tape to peel off a few layers (a.k.a. flakes) at a time. "This was very important because it allowed us to use electron-beam lithography (like photo-lithography which is used to make computer chips, but using electrons rather than photons) to make tiny devices out of the flakes and measure properties which people can't easily measure in bulk." remarked lead author Shuo-Ying Yang, from the Max Planck Institute of Microstructure Physics. "We were excited to find that the flakes were quite stable to the fabrication process, which makes it relatively easy to work with and explore lots of properties".

Armed with this combination of properties, the team first chose to look for an anomalous Hall effect (AHE) in the material. This phenomenon is where electrons in a material with an applied electric field (but no magnetic field) can get deflected by 90 degrees by various mechanisms. "It had been theorized that metals with triangular spin arrangements could host a significant extrinsic effect, so it was a good place to start," noted Yang. Using angle resolved photoelectron spectroscopy, microdevice fabrication, and a low temperature electronic property measurement system, Shuo-Ying and co-lead author Yaojia Wang (Max Planck Institute of Microstructure Physics) were able to observe one of the largest AHE's ever seen.

The AHE can be broken into two general categories: intrinsic and extrinsic. "The intrinsic mechanism is like if a football player made a pass to their teammate by bending the ball, or electron, around some defenders (without it colliding with them)," explained Ali. "Extrinsic is like the ball bouncing off of a defender, or magnetic scattering center, and going to the side after the collision. Many extrinsically dominated materials have a random arrangement of defenders on the field, or magnetic scattering centers randomly diluted throughout the crystal. KV3Sb5 is special in that it has groups of 3 magnetic scattering centers arranged in a triangular net. In this scenario, the ball scatters off of the cluster of defenders, rather than a single one, and is more likely to go to the side than if just one was in the way." This is essentially the theorized spin-cluster skew scattering AHE mechanism which was demonstrated by the authors in this material. "However the condition with which the incoming ball hits the cluster seems to matter; you or I kicking the ball isn't the same as if, say, Christiano Ronaldo kicked the ball," added Ali. "When Ronaldo kicks it, it is moving way faster and bounces off of the cluster with way more velocity, moving to the side faster than if just any average person had kicked it. This is, loosely speaking, the difference between the Dirac quasiparticles (Ronaldo) in this material vs normal electrons (average person) and is related to why we see such a large AHE," Ali laughingly explained.

These results may also help scientists identify other materials with this combination of ingredients. "Importantly, the same physics governing this AHE could also drive a very large spin Hall effect (SHE) - where instead of generating an orthogonal charge current, an orthogonal spin current is generated," remarked Wang. "This is important for next-generation computing technologies based on an electron's spin rather than its charge".

"This is a new playground material for us: metallic Dirac physics, frustrated magnetism, exfoliatable, and chemically stable all in one. There is a lot of opportunity to explore fun, weird phenomena, like unconventional superconductivity and more," said Ali, excitedly.

Skoltech scientists have shown that quantum enhanced machine learning can be used on quantum (as opposed to classical) data, overcoming a significant slowdown common to these applications and opening a "fertile ground to develop computational insights into quantum systems". The paper was published in the journal Physical Review A.

Quantum computers utilize quantum mechanical effects to store and manipulate information. While quantum effects are often claimed to be counterintuitive, such effects will enable quantum enhanced calculations to dramatically outperform the best supercomputers. In 2019, the world saw a prototype of this demonstrated by Google as quantum computational superiority.

Quantum algorithms have been developed to enhance a range of different computational tasks; more recently this has grown to include quantum enhanced machine learning. Quantum machine learning was partly pioneered by Skoltech's resident-based Laboratory for Quantum Information Processing, led by Jacob Biamonte, a coathor of this paper. "Machine learning techniques have become powerful tools for finding patterns in data. Quantum systems produce atypical patterns that classical systems are thought not to produce efficiently, so it is not surprising that quantum computers might outperform classical computers on machine learning tasks," he says.

The standard approach to quantum enhanced machine learning has been to apply quantum algorithms to classical data. In other words, classical data (represented by bit strings of 1's and 0's) must be stored or otherwise represented by a quantum processor before quantum effects can be utilized. This is called the data-readin problem. Data-readin serves to limit the speedup that is possible using quantum enhanced machine learning algorithms.

A team of Skoltech researchers has merged quantum enhanced machine learning with quantum enhanced simulation, applying their approach to study phase transitions in many-body quantum magnetic problems. In doing so, they train quantum neural networks using only quantum states as data. In other words, the authors circumvent the data-readin problem by feeding in quantum mechanical states of matter. Such states appear to generally require an impossible amount of memory to represent using standard (non-quantum) approaches.

The lead author of the study, Skoltech doctoral student Alexey Uvarov describes the study as "a step towards understanding the power of quantum devices for machine learning." Researchers merged an assortment of techniques, which included applying some ideas from tensor networks and entanglement theory in the analysis of their approach.

The work uses a subroutine known as the variational quantum eigensolver (VQE) -- an algorithm that iteratively finds an approximation to the ground state of a given quantum Hamiltonian. The output of this subroutine is a set of instructions to prepare a quantum state on a quantum computer.

Writing the state down explicitly, though, typically requires an exponential amount of memory, hence the properties of such a state are best examined by preparing it in hardware. The learning algorithm in the paper deals with the following problem: given a VQE state solving the ground state problem for a quantum spin model, find out which of the two phases of matter that state belongs to.

"While we have focused our approaches on problems from condensed matter physics, such quantum enhanced algorithms equally apply to challenges faced in materials science and drug discovery," Biamonte notes.

Researchers at the University of the Witwatersrand in Johannesburg, South Africa, have demonstrated a record setting quantum protocol for sharing a secret amongst many parties. The team created an 11-dimensional quantum state and used it to share a secret amongst 10 parties. By using quantum tricks, the secret can only be unlocked if the parties trust one another. The work sets a new record for the dimension of the state (which impacts on how big the secret can be) and the number of parties with whom it is shared and is an important step towards distributing information securely across many nodes in a quantum network.

Laser & Photonics Reviews published online the research by the Wits team led by Professor Andrew Forbes from the School of Physics at Wits University. In their paper titled: Experimental Demonstration of 11-Dimensional 10-Party Quantum Secret Sharing, the Wits team beat all prior records to share a quantum secret.

"In traditional secure quantum communication, information is sent securely from one party to another, often named Alice and Bob. In the language of networks, this would be considered peer-to-peer communication and by definition has only the two nodes: sender and receiver," says Forbes.

"Anyone who has sent an email will know that often information must be sent to several people: one sender and many receiving parties. Traditional quantum communication such as quantum key distribution (QKD) does not allow this, and is only of the peer-to-peer form."

Using structured light as quantum photon states, the Wits team showed how to distribute information from one sender to 10 parties. Then, by using some nifty quantum tricks, they could engineer the protocol so that only if the parties trust one another can the secret be revealed.

"In essence, each party has no useful information, but if they trust one another then the secret can be revealed. The level of trust can be set from just a few of the parties to all of them," says Forbes. Importantly, at no stage is the secret ever revealed through communication between the parties: they don't have to reveal any secrets. In this way a secret can be shared in a fundamentally secure manner across many nodes of a network: quantum secret sharing.

"Our work pushes the state-of-the-art and brings quantum communication closer to true network implementation," says Forbes. "When you think of networks you think of many connections, many parties, who wish to share information and not just two. Now we know how to do this the quantum way."

The team used structured photons to reach high dimensions. Structured light means ''Patterns of light" and here the team could use many patterns to push the dimension limit. More dimensions mean more information in the light, and translates directly to larger secrets.

A new study shows that moist heat treatment of N95 masks eliminates severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and bacteria, which would allow reuse of these scarce resources. The study is published in CMAJ (Canadian Medical Association Journal).

The researchers found that moist heat treatment (60 min, 70°C, 50% relative humidity) did not damage the mask's structure or affect function.

"This low-cost reprocessing strategy can be applied 10 times without affecting the mask's filtration, breathing resistance, fit and comfort, and thus may help to alleviate the global shortage during the COVID-19 pandemic," says Dr. Gregory Borschel, Institute of Biomaterials and Biomedical Engineering and Division of Plastic and Reconstructive Surgery, The Hospital for Sick Children (SickKids), Toronto, Ontario.

Researchers tested 4 common models of N95 masks at various temperatures and humidity levels to determine whether the virus could be detected on the treated masks. They also analyzed fibre samples for structural integrity and assessed function of the masks after treatment with heat.

"Thermal disinfection of N95 masks may provide a low-cost, effective method for regions with fewer resources to extend their supply of these critical resources, thereby protecting vulnerable front-line workers from job-related risk of infection," says Dr. Borschel.

Philadelphia, July 31, 2020--Continuous glucose monitoring (CGM) tracks glucose levels of people with type I or type II diabetes through a device that monitors levels throughout the day. These devices improve control of blood sugar levels by alerting patients when their levels go too high or low, but patients need to use the technology consistently to derive a benefit. Previous studies have shown that youth are less likely than adults to use CGM consistently, so there is a need to identify factors that lead to long-term CGM use in youth.

In a new study published in Diabetes Care, researchers at Children's Hospital of Philadelphia (CHOP) have found that youth who are involved with the decision to start CGM are more likely to continue using the monitoring technology more than two months after starting. The findings suggest that children and adolescents who do not have a role in the decision are less likely to be satisfied with the device and use the device consistently.

"To maximize the clinical benefits of CGM, our results suggest that providers should involve youth in the decision-making process from the beginning, eliciting their opinions, concerns, and questions about the device and providing information about the device directly to them," said Victoria A. Miller, PhD, a psychologist in the Craig-Dalsimer Division of Adolescent Medicine at CHOP. "Parents also have a role to play, and providers can encourage parents to engage their children in conversations about the decision to start CGM without dominating the discussion, which may increase the likelihood that they are in agreement about waiting or proceeding."

The study analyzed 108 parent-child pairs and found that when parents reported their children spoke up more in discussions about CGM, children used the technology more regularly up to 12 weeks after beginning use. Conversely, when parents reported that they themselves spoke up more in discussions about CGM, their children used the technology less frequently two months after starting. Researchers also found that when parents reported their children spoke up more in discussions about CGM, the children had stronger beliefs in their ability to use CGM successfully and were less likely to perceive CGM as a hassle at a two-month follow-up.

The authors noted a few limitations to their study, including the fact that the sample population was primarily non-Hispanic white and parent participants were mostly mothers. The study also only used one CGM brand. As such, the findings may not be generalizable to more diverse populations, father-child pairs, or families who choose different CGM brands. Additionally, those who participated in the study may have been, by their willingness to participate, more open to talking about diabetes, so the results may not apply to those who are more reticent to talk about diabetes or who are overwhelmed with managing their condition.

"Additional research is needed to develop strategies that enhance children's involvement in the decision about CGM, prevent declines in CGM use over time, and maximize the clinical benefits that can be obtained by appropriate use of CGM and other emerging technologies for diabetes management," Miller said. "Such research should also target more diverse samples to examine the extent to which sociodemographic factors, such as race, ethnicity, and socioeconomic status, impact CGM uptake and use."

Tyrosine kinases are protein enzymes that have many functions within cells, including cell signaling, growth, and division. Sometimes these enzymes can be overactive, which helps cancer cells survive and multiply. A tyrosine kinase inhibitor (TKI) is a medication given to certain acute myeloid leukemia (AML) patients to block the actions of overactive tyrosine kinases, with the ultimate goal of stopping or slowing cancer cell growth. In a study published in the journal Leukemia, lead author Ami Patel, MD, Huntsman Cancer Institute (HCI) researcher and assistant professor in the Division of Hematology and Hematologic Malignancies at the University of Utah (U of U), showed that factors produced by bone marrow support cells allowed leukemia cells to survive treatment with quizartinib, a type of TKI. When quizartinib was combined with another TKI called dasatinib the alternative survival pathways were shut down, leading to more effective leukemia cell death. Patel and colleagues believe this study helps to outline a potential new treatment approach in AML patients who have a mutation in a gene called FLT3.

AML is a type of blood cancer that affects white blood cells in the body. About 30% of all AML patients have a mutation in a tyrosine kinase called FLT3. This protein sits on the surface of blood cells and binds to a specific molecule called FL outside the cell. Normally, binding of FL activates the FLT3 receptor and causes cell growth. However, when mutations occur in FLT3 growth signals are sent to leukemia cells even when FL is not present. Quizartinib is a type of FLT3 inhibitor that was developed for AML patients with FLT3 mutations.

AML patients respond well to quizartinib initially, but usually their disease returns shortly after treatment. "It is amazing to see how small molecule inhibitors have transformed cancer care for so many leukemia patients," said Patel. "However, the sobering reality is that even new and exciting drugs often only work to control leukemia for a finite period of time before the patient develops drug resistance and relapses."

Using blood and marrow samples donated by AML patients at HCI, Patel found that factors produced by bone marrow support cells are taken up by leukemia cells, activating survival pathways that protect leukemia cells from being killed by quizartinib. One of the signaling pathways activated in leukemia cells was the STAT5 pathway. Patel also found that these bone marrow factors speed up energy production in leukemia cells, allowing for cancer cell survival. Treating leukemia cells with a combination of quizartinib and dasatinib overcame the protective effects from bone marrow support cells in this laboratory study and killed leukemia cells more effectively than quizartinib alone.

Patel plans to use these findings to support future studies of resistance to TKIs in another type of leukemia called chronic myelomonocytic leukemia. Collectively, insights from these studies will be used to develop clinical trials to improve treatment options for leukemia patients.

Epilepsy is a wide-spread neurological disorder that affects around 50 million people worldwide. It is characterized by recurrent epileptic seizures, which are sudden bursts of electrical activity in the brain. There are many different types of seizures, and a person with epilepsy can experience more than one type.

Clinicians today use EEG measurements, with electrodes either placed on a patient's scalp or inside the brain, to identify when and where a seizure begins. But these measurements alone do not always provide enough information to understand the type of seizure and make optimal decisions regarding treatment.

Now, an international team of researchers led by Aix-Marseille University in France and the University of Michigan has proposed a new classification system of seizures based on a deep understanding and mathematical modelling of brain oscillations. "It represents the first objective and unbiased taxonomy of its kind", says one of the lead authors, HBP-scientist Prof. Viktor Jirsa from Aix-Marseille University.

The researchers used "bifurcation theory" - a method commonly used in fields such as physics and engineering - to analyze data from over a hundred patients across the globe. Researchers from the University of Melbourne and Monash University, both in Australia, the University of Freiburg in Germany, and Kyoto University in Japan also contributed to the work. Seizures with similar properties were categorized into groups.

They found sixteen types of seizure dynamics - or 'dynamotypes' - with distinct characteristics. "Similar to the periodic table of elements in chemistry, we demonstrated the existence of a clear classification system of seizures", says Jirsa.

The system could lead clinicians to a better understanding of seizures and how they should be treated. "Seizure types react differently to treatments. For instance, some seizures can be stopped through electric stimulation, others not, dependent on their dynamotype. The systems scientific basis is theory work developed around the Epileptor, a central epilepsy model we developed in the Human Brain Project that is also at the heart of a large clinical trial running now", the researcher explains.

"Classification, however, is not explanation ", Jirsa emphasises. " There is much work ahead of us to better understand epilepsy mechanisms. This is where EBRAINS will play a key role, as it provides the tools connecting cellular, network and brain imaging signals aiding in mechanism discovery. " EBRAINS is a new shared digital brain research infrastructure for the European Union that the Human Brain Project (HBP) is building.

Within the HBP, Jirsa and his team had first begun adapting the open network simulator The Virtual Brain towards applications in epilepsy. The work has laid the foundations for project EPINOV ("Improving EPilepsy surgery management and progNOsis using Virtual brain technology") a multi-year project involving more than a dozen French hospitals that is funded by the French state. EPINOV tests whether the use of the personalized HBP modeling technology for epilepsy networks can improve surgery preparation in drug-resistant patients.

When we say someone has a quick mind, it may be in part thanks to our expanded cerebellum that distinguishes human brains from those of macaque monkeys, for example.

Sometimes referred to by its Latin translation as the '"little brain"', the cerebellum is located close to the brainstem and sits under the cortex in the hindbrain. New research at San Diego State University, however, calls the "little" terminology into question.

The cerebellum plays a versatile role, contributing to our five senses as well as pain, movements, thought, and emotion.

It's essentially a flat sheet with the thickness of a crepe, crinkled into hundreds of folds to make it fit into a compact volume about one-eighth the volume of the cerebral cortex. For this reason, the surface area of the cerebellum was thought to be considerably smaller than that of the cerebral cortex.

By using an ultra-high-field 9.4 Tesla MRI machine to scan the brain and custom software to process the resulting images, an SDSU neuroimaging expert discovered the tightly packed folds actually contain a surface area equal to 80% of the cerebral cortex's surface area. In comparison, the macaque's cerebellum is about 30% the size of its cortex.

"The fact that it has such a large surface area speaks to the evolution of distinctively human behaviors and cognition," said Martin Sereno, psychology professor, cognitive neuroscientist and director of the SDSU MRI Imaging Center. "It has expanded so much that the folding patterns are very complex."

Unprecedented insights

Collaborating with imaging and cerebellum experts from the United Kingdom, Netherlands and Canada, Sereno used customized open source FreeSurfer software that he originally developed with colleagues while at the University of California San Diego to computationally reconstruct the folded surface of the cerebellum. The software also unfolds and flattens the cerebellar cortex so as to visualize it to the level of each individual folia -- or thin leaf like fold.

A pioneer in brain imaging who has leveraged functional MRI to uncover visual maps in the brain, Sereno found that when the cerebellum is completely unfolded, it forms a strange "crepe" four inches wide by three feet long. The findings were published this week in a study in PNAS (Proceedings of the National Academy of Sciences).

"Until now we only had crude models of what it looked like," Sereno said. "We now have a complete map or surface representation of the cerebellum, much like cities, counties, and states."

Puzzle pieces

Previous research discovered that while there were many similarities between the cortex and the cerebellum, there was one key difference. In the cerebral cortex, regions representing different parts of the body are arranged roughly like they are in the actual body: juxtaposed and orderly. But in the cerebellum, they were placed more randomly.

"You get a little chunk of the lip, next to a chunk of the shoulder or face, like jumbled puzzle pieces," Sereno explained.

Those parts of the cerebellum are therefore set up to pull in and coordinate information from disparate parts of the body.

It is intriguing to think that there might be analogs of '"fractured somatotopy"' in the cognitive parts of the cerebellum that could help support highly complex, sophisticated cognitive functions, such as language or abstract reasoning, Sereno said.

"When you think of the cognition required to write a scientific paper or explain a concept, you have to pull in information from many different sources. And that's just how the cerebellum is set up."

Until now, the cerebellum was thought to be involved mainly in basic functions like movement, but its expansion over time and its new inputs from cortical areas involved in cognition suggest that it can also process advanced concepts like mathematical equations.

"Now that we have the first high resolution base map of the human cerebellum, there are many possibilities for researchers to start filling in what is certain to be a complex quilt of inputs, from many different parts of the cerebral cortex in more detail than ever before," Sereno said.

For instance, there is some recent evidence that people who suffer cerebellum damage have difficulty processing emotion.

"The 'little brain' is quite the jack of all trades," Sereno said. "Mapping the cerebellum will be an interesting new frontier for the next decade."

The background of this research is based on the use of large interbody spacers in minimally invasive (MIS) lateral lumbar interbody fusion (LLIF) that offer favorable clinical and radiographic results. The static interbody spacers are likely to cause iatrogenic endplate damage and implant subsidence due to strong impaction and too much trialing. Whereas expandable interbody spacers with adjustable lordosis offer in situ expansion that bear the potential to optimize endplate contact and maximize and maintain sagittal alignment correction until fusion occurs.

The aim of this study was to understand the clinical and radiographic outcomes amongst patients treated with static and expandable interbody spacers with adjustable lordosis for minimally invasive (MIS) lateral lumbar interbody fusion (LLIF). This research essentially is a multi-surgeon, retrospective, Institutional Review Board-exempt chart review of those patients who underwent MIS LLIF at 1-2 contiguous level(s) using either a polyetheretherketone (PEEK) static or a titanium expandable spacer with adjustable lordosis. The researchers collected the mean differences of radiographic and clinical functional outcomes and compared from preoperative up to 12-month postoperative follow-up.

The result of the study showed significant positive clinical and radiographic outcomes for patients who underwent MIS LLIF using titanium expandable interbody spacers with adjustable lordosis.

NEW YORK, NY (July 31, 2020) -- U.S. Google searches for information about financial difficulties and disaster relief increased sharply in March and April compared to pre-pandemic times, while googling related to suicide decreased, researchers at Columbia University Irving Medical Center have found.

Because previous research has shown that financial distress is strongly linked to suicide mortality, the researchers fear that the increase may predict a future increase in deaths from suicide.

The findings were published online in PLOS One.

"The scale of the increase in Google searches related to financial distress and disaster relief during the early months of the pandemic was remarkable, so this finding is concerning," says Madelyn Gould, PhD, MPH, Irving Philips Professor of Epidemiology in Psychiatry at Columbia University Vagelos College of Physicians and Surgeons and senior author of the study.

Pandemics and suicide

Researchers in the United States and elsewhere have begun studying the effects of the COVID-19 pandemic on mental health, but the impact on suicidal behavior and deaths is difficult to assess due to lag time in the availability of mortality data.

Previous studies suggest that suicide rates often decrease in the immediate aftermath of national disasters, such as 9/11, but may increase several months later, as seen after the 1918 flu pandemic and the 2003 SARS outbreak in Hong Kong.

Studies in the U.S. and internationally have linked Google search behavior with suicidal behavior, so in the current study, the researchers evaluated online searches about suicide and suicide risk factors during the early part of the pandemic and potential long-term impact on suicide.

The researchers used an algorithm to analyze Google trends data from March 3, 2019, to April 18, 2020, and identify proportional changes over time in searches for 18 terms related to suicide and known suicide risk factors.

"We didn't have a clear hypothesis about whether there would be an increase in suicide-related queries during this period of time, but we anticipated a national sense of community during the pandemic that might mitigate suicidal behavior in the short term," says Emily Halford, MPH, data analyst and the study's first author.

Unemployment, panic attacks, and loneliness may predict future suicide

The researchers found dramatic relative increases (in the thousands of percentages, in some cases) in Googling search terms related to financial distress -- e.g., "I lost my job," "unemployment," and "furlough" -- and for the national Disaster Distress Helpline.

The proportion of queries related to depression was slightly higher than the pre-pandemic period, and moderately higher for panic attack.

"It seems as though individuals are grappling with the immediate stresses of job loss and isolation and are reaching out to crisis services for help, but the impact on suicidal behavior hasn't yet manifested," says Gould. "Generally, depression can take longer to develop, whereas panic attacks may be a more immediate reaction to job loss and having to deal with emotionally charged events amidst the social isolation of the pandemic."

Searches for terms related to loneliness were also meaningfully higher during the early pandemic period versus the prior year.

Gould adds that social distancing is one of the primary measures implemented to slow the spread of the coronavirus, "but this approach may have detrimental secondary effects, such as loneliness and exacerbation of preexisting mental illnesses, which are known suicide risk factors."

Meeting the anticipated need for crisis services

The researchers say that in light of an anticipated increase in suicidal crises, it will be important to ensure continued availability and accessibility of crisis services and other mental health services during the later stages of the pandemic.

"The current findings give us insight into how people have been dealing with the immediate emotional and financial effects of the pandemic," says Gould. "Encouragingly, individuals who Google terms related to suicide are directed to the National Suicide Prevention Lifeline. We are hoping that accessing this crisis service may ameliorate suicide risk among the individuals who have Googled suicide-related terms."

More Information

If you or someone you know is thinking about suicide, contact the National Suicide Prevention Lifeline 24/7 for free, confidential support by calling 1-800-273-8255 (1-800-273-TALK) and through online chats.

Using real-world data and predictive models, investigators identify key factors that determine success of fecal microbiota transplantation

Framework also provides an algorithm for designing a personalized probiotic cocktail to decolonize harmful bacteria in the gut

We may not think about it often, but our gut is home to a complex ecosystem of microorganisms that play a critical role in how we function. The system is delicate -- one small change can cause a major shift in the microbiome, resulting in serious consequences. When a person takes an antibiotic, it can wipe out multiple bacterial species and throw this delicate balance off-kilter. Clostridioides difficile is a common pathogen that colonizes a disrupted gut microbiota. Fecal microbiota transplantation (FMT), in which stool from a healthy donor is transplanted into the colon of a recipient, is a successful treatment for recurrent C. difficile infection (rCDI). In a recently published study, investigators from Brigham and Women's Hospital explore how the dynamics of bacterial species may influence the success of FMT in treating rCDI. In Nature Communications, the team presents an algorithm to design personalized probiotic cocktails for patients with unhealthy gut microbiomes due to rCDI.

"Designing a probiotic cocktail is challenging," said Yang-Yu Liu, PhD, an assistant professor in the Department of Medicine at the Brigham. "All of the species in the cocktail interact within a complicated network. When we look at one species that directly inhibits the growth of C. difficile, we must also make sure that it does not indirectly promote growth of C. difficile through interactions with other species in the cocktail."

C. difficile is transmitted through the fecal-oral route -- poor hygiene or the contamination of food or water supply -- and is found all over the world. Although C. difficile will not typically colonize a healthy colon, it can grow unchecked in a gut that has been disrupted due to antibiotics. rCDI is not responsive to standard antibiotics and therefore can recur in patients, increasing the risk each time. FMT has been shown to cure about 80 percent of rCDI cases that did not respond to antibiotics.

The researchers began by modeling a microbial community and simulating the FMT process of treating rCDI. Next, they estimated how effective FMT would be at restoring the recipient's healthy gut microbiota. The team then analyzed real-world data from a mouse model and from human patients to validate the modeling.

The theoretical model helped the team predict what factors determine the efficacy of FMT. They learned that FMT efficacy decreases as the species diversity of the infected person's gut microbiome increases. The team also developed an optimization algorithm to design a personalized probiotic cocktail to help individuals with rCDI. The algorithm is based on ecological theory that designs a cocktail with the minimum number of bacterial species, while keeping the complicated ecological network of the species in mind. The personalized probiotic cocktails contain species that are effective inhibitors of C. difficile and can be administered to patients with rCDI in order to restore their gut microbiota.

"We now have an ecological understanding of FMT -- why it works and why it sometimes fails for rCDI," said Liu. "We can move forward to better understand the efficacy of FMT and how we can use it to treat other diseases associated with disrupted microbiota, such as IBD, autism and obesity."

Semiconductors are important materials in numerous functional applications such as digital and analog electronics, solar cells, LEDs, and lasers. Semiconducting alloys are particularly useful for these applications since their properties can be engineered by tuning the mixing ratio or the alloy ingredients. However, the synthesis of multicomponent semiconductor alloys has been a big challenge due to thermodynamic phase segregation of the alloy into separate phases. Recently, University of Michigan researchers Emmanouil (Manos) Kioupakis and Pierre F. P. Poudeu, both in the Materials Science and Engineering Department, utilized entropy to stabilize a new class of semiconducting materials, based on GeSnPbSSeTe high-entropy chalcogenide alloys,[1] a discovery that paves the way for wider adoption of entropy-stabilized semiconductors in functional applications. Their article, "Semiconducting high-entropy chalcogenide alloys with ambi-ionic entropy stabilization and ambipolar doping" was recently published in the journal Chemistry of Materials.

Entropy, a thermodynamic quantity that quantifies the degree of disorder in a material, has been exploited to synthesize a vast array of novel materials by mixing eachcomponent in an equimolar fashion, from high-entropy metallic alloys to entropy-stabilized ceramics. Despite having a large enthalpy of mixing, these materials can surprisingly crystalize in a single crystal structure, enabled by the large configurational entropy in the lattice. Kioupakis and Poudeu hypothesized that this principle of entropy stabilization can be applied to overcome the synthesis challenges of semiconducting alloys that prefer to segregation into thermodynamically more stable compounds. They tested their hypothesis on a 6-component II-VI chalcogenide alloy derived from the PbTe structure by mixing Ge, Sn, and Pb on the cation site, and S, Se, and Te on the anion site.

Using high throughput first-principles calculations, Kioupakis uncovered the complex interplay between the enthalpy and entropy in GeSnPbSSeTe high-entropy chalcogenide alloys. He found that the large configurational entropy from both anion and cation sublattices stabilizes the alloys into single-phase rocksalt solid solutions at the growth temperature. Despite being metastable at room temperature, these solid solutions can be preserved by fast cooling under ambient conditions. Poudeu later verified the theory predictions by synthesizing the e

quimolar composition (Ge1/3Sn1/3Pb1/3S1/3Se1/3Te1/3) by a two-step solid-state reaction followed by fast quenching in liquid nitrogen. The synthesized power showed well-defined XRD patterns corresponding to a pure rocksalt structure. Furthermore, they observed reversible phase transition between single-phase solid solution and multiple-phase segregation from DSC analysis and temperature dependent XRD, which is a key feature of entropy stabilization.

What makes high-entropy chalcogenide intriguing is their functional properties. Previously discovered high-entropy materials are either conducting metals or insulating ceramics, with a clear dearth in the semiconducting regime. Kioupakis and Poudeu found that. the equimolar GeSnPbSSeTe is an ambipolarly dopable semiconductor, with evidence from a calculated band gap of 0.86 eV and sign reversal of the measured Seebeck coefficient upon p-type doping with Na acceptors and n-type doping with Bi donors. The alloy also exhibits an ultralow thermal conductivity that is nearly independent of temperature. These fascinating functional properties make GeSnPbSSeTe a promising new material to be deployed in electronic, optoelectronic, photovoltaic, and thermoelectric devices.

Entropy stabilization is a general and powerful method to realize a vast array of materials compositions. The discovery of entropy stabilization in semiconducting chalcogenide alloys by the team at UM is only the tip of the iceberg that can pave the way for novel functional applications of entropy-stabilized materials.

Research on solar cells to secure renewable energy sources are ongoing around the world. The Electronics and Telecommunications Research Institute (ETRI) in South Korea succeeded in developing eco-friendly color Cu(In,Ga)Se2 (CIGS) thin-film solar cells.

CIGS thin-film solar cells are used to convert sunlight into electrical energy and are made by coating multiple thin films on a glass substrate. They have a relatively higher absorption coefficient among non-silicon based cells, resulting in high conversion efficiency and long stability. Also, they require less raw materials compared to silicon-based cells; hence less process and material costs.

One downside has been the difficulty in commercialization as they use the buffer layer which contains toxic heavy metal, cadmium. Thus, the ETRI team replaced the cadmium sulfide (CdS) buffer layer with zinc (Zn) based materials-- which is not harmful -- and managed to achieve approximately 18% conversion efficiency; thus eliminating the obstacle to commercialization.

Likewise, the availability of more than 7 colors including purple, green, and blue -- without the need for additional process or cost -- means one step closer to full-on commercialization. Moreover, the researchers succeeded in identifying a new analysis method using photo-pumping terahertz spectroscopy and a mechanism for improving the conversion efficiency of solar cells with Zn-based buffer layers.

The solar cells are only 3? thick and can be coated on a flexible substrate as well as a glass substrate. This means that they could be bent or folded, expanding applications as a next-generation eco-friendly energy source.

"This technology will contribute to the solar power system development through the production of high value-added color photovoltaic modules," said Yong-Duck Chung, the ETRI principal researcher.

The excellence of the research was proven by its publication in 'Nano Energy' and 'Progress in Photovoltaics: Research and Applications' as the cover article, globally esteemed international journals in the energy sector.