Brain

Monash University researchers have uncovered the barrier to β-cell (beta cell) regeneration that could pave the way for improved treatments for diabetes and diseases that involve organ and tissue damage.

The human body doesn't repair itself very well, with our liver the only organ that can regenerate efficiently. We have limited capacity to regenerate new cells or tissue after birth as the genes involved in development are switched off.

This process happens through DNA methylation, a biological process where chemicals (methyl groups) are written on DNA and modify the way the gene functions. This modification effectively silences genes of progenitor cells (early descendants of stem cells) in the body and thereby the ability for the pancreas to generate the insulin producing β-cells.

Using mouse models, the study published in Regenerative Medicine, led by Professor Sam El-Osta from Monash Central Clinical School, found that the DNA methylation content of two key developmental genes Ngn3 and Sox 11 were diminished, effectively making them 'repair' dormant.

However, through demethylation, progenitor cells can be reawakened, restoring their capacity to become new insulin producing beta cells paving the way towards improved treatments for Type 1 and Type 2 diabetes.

"The collaboration between Dr Keith Al-Hasani and Dr Ishant Khurana has unveiled some surprising results. Their discovery that DNA methylation is a barrier to adult beta-cell regeneration will assist scientists to restore beta-cell function in the pancreas," said Professor El-Osta.

Currently, replacing the damaged β-cell mass in diabetic patients consists of whole pancreas or islets transplantation. Although efficient, these therapies face the shortage of organ donors together with the associated side effects of immunosuppressive drugs.

Current research focuses on the replacement of the lost β-cells in diabetic patients using several approaches and cell sources. However, critical to exploiting the potential of these regenerative approaches, is understanding how tissue and cellular processes are controlled during development.

Co-first author on the study, Dr Keith Al-Hasani added: "This is a novel and significant finding that will allow us to use these "sleeping beauties" (stem cells like cells) to wake up and become insulin cells to cure diabetes."

CHAMPAIGN, Ill. -- People who participated in a health education program that included both mental health and physical health information significantly reduced their risks of cardiovascular disease and other chronic diseases by the end of the 12-month intervention - and sustained most of those improvements six months later, researchers found.

People who participated in the integrated mental and physical health program maintained significant improvements on seven of nine health measures six months after the program's conclusion. These included, on average, a 21% decrease in fasting blood sugar, a 17% decrease in low-density lipoprotein cholesterol and a 12% decrease in their body mass index.

However, patients in the group that focused only on physical health information maintained their improvements on just two risk factors - BMI and systolic blood pressure.

Data collected at the conclusion of the 12-month intervention indicated that patients in the program with the mental health component improved on eight of nine health measures, while their peers in the traditional program improved on just three.

"The gains achieved by patients in the integrated program were greater than those of their counterparts in the other group and had greater lasting effects," said University of Illinois Urbana-Champaign social work professor Tara M. Powell, the first author of a study on the project, published in the journal Preventive Medicine Reports.

Study participants were 213 Syrian refugees and 382 Jordanians who were patients of three health clinics in Irbid, Jordan, a border community that has experienced a large influx of people fleeing the civil war in Syria.
Powell conducted the research in partnership with the health-focused relief and development nonprofit organization Americares and the Royal Health Awareness Society, Jordan.

Powell's group explored the efficacy of a health education intervention called the Healthy Community Clinic, delivered in clinics throughout Jordan to improve patients' management of chronic conditions such as cardiovascular disease and diabetes, and reduce their risks of complications. Trained health educators or nurses led 20 interactive educational sessions that patients attended twice a month for one year.

Patients' outcomes in the traditional HCC program were compared with those of peers who received routine health care only and with a group who participated in an expanded HCC program that integrated four additional sessions focused on mental health.

The mental health sessions included discussions of topics such as grief and physical and emotional traumatic stress reactions. Participants also learned tangible coping skills for reducing emotional distress such as deep-breathing exercises and walking.

"This study is among the first to illustrate how an integrated physical and mental health educational intervention can improve health outcomes and ultimately help reduce cardiovascular disease risk in refugees and low-income populations," said co-principal investigator Dr. Shang-Ju Li, Americares' senior director of monitoring and evaluation. "We are thrilled to share this groundbreaking research and look forward to making even more progress as we continue to look for ways to improve health outcomes for people affected by poverty or disaster."

Additional co-authors of the study were Michelle Thompson, an associate director of emergency response, Americares; sociology graduate student Yuan Hsiao of the University of Washington; Aseel Farraj, a program manager of the Royal Health Awareness Society; Mariam Abdoh, a senior population and health advisor/project management specialist, USAID; and Dr. Rami Farraj, of the King Hussein Medical Center.

Based upon the findings of this research, the Royal Health Awareness Society has since deployed the HCC with the mental health component to public health centers across Jordan, Powell said.

In a prior study with the same participants that examined the impact of social support on mental and physical health, Powell and her colleagues found that more than half of the participants had experienced at least one traumatic event. Among Syrians, the most frequently reported traumatic experience was living in a war zone (73%), while among Jordanians it was witnessing a violent death (18%).

That study, published in PLOS ONE, was co-written by Li, Hsiao and U. of I. graduate student Oe Jin Shin.

"Because mental health conditions such as depression and anxiety often co-occur with chronic physical problems and with poverty, patient education programs that integrate mental and physical health information are critical for countries such as Jordan," Powell said. "Making these integrated programs widely available can reduce the burden of noncommunicable diseases on marginalized populations and increase their access to care."

To build a universal quantum computer from fragile quantum components, effective implementation of quantum error correction (QEC) is an essential requirement and a central challenge. QEC is used in quantum computing, which has the potential to solve scientific problems beyond the scope of supercomputers, to protect quantum information from errors due to various noise.

Published by the journal Nature, research co-authored by University of Massachusetts Amherst physicist Chen Wang, graduate students Jeffrey Gertler and Shruti Shirol, and postdoctoral researcher Juliang Li takes a step toward building a fault-tolerant quantum computer. They have realized a novel type of QEC where the quantum errors are spontaneously corrected.

Today's computers are built with transistors representing classical bits (0's or 1's). Quantum computing is an exciting new paradigm of computation using quantum bits (qubits) where quantum superposition can be exploited for exponential gains in processing power. Fault-tolerant quantum computing may immensely advance new materials discovery, artificial intelligence, biochemical engineering and many other disciplines.

Since qubits are intrinsically fragile, the most outstanding challenge of building such powerful quantum computers is efficient implementation of quantum error correction. Existing demonstrations of QEC are active, meaning that they require periodically checking for errors and immediately fixing them, which is very demanding in hardware resources and hence hinders the scaling of quantum computers.

In contrast, the researchers' experiment achieves passive QEC by tailoring the friction (or dissipation) experienced by the qubit. Because friction is commonly considered the nemesis of quantum coherence, this result may appear quite surprising. The trick is that the dissipation has to be designed specifically in a quantum manner. This general strategy has been known in theory for about two decades, but a practical way to obtain such dissipation and put it in use for QEC has been a challenge.

"Although our experiment is still a rather rudimentary demonstration, we have finally fulfilled this counterintuitive theoretical possibility of dissipative QEC," says Chen. "Looking forward, the implication is that there may be more avenues to protect our qubits from errors and do so less expensively. Therefore, this experiment raises the outlook of potentially building a useful fault-tolerant quantum computer in the mid to long run."

Chen describes in layman's terms how strange the quantum world can be. "As in German physicist Erwin Schrödinger's famous (or infamous) example, a cat packed in a closed box can be dead or alive at the same time. Each logical qubit in our quantum processor is very much like a mini-Schrödinger's cat. In fact, we quite literally call it a `cat qubit.' Having lots of such cats can help us solve some of the world's most difficult problems.

"Unfortunately, it is very difficult to keep a cat staying that way since any gas, light, or anything leaking into box will destroy the magic: The cat will become either dead or just a regular live cat," explains Chen. "The most straightforward strategy to protect a Schrodinger's cat is to make the box as tight as possible, but that also makes it harder to use it for computation. What we just demonstrated was akin to painting the inside of the box in a special way and that somehow helps the cat better survive the inevitable harm of the outside world."

A team of Russian scientists from NUST MISIS, Tomsk Polytechnic University (TPU) and Boreskov Institute of Catalysis has suggested a new approach to modifying the combustion behavior of coal. The addition of copper salts reduces the content of unburnt carbon in ash residue by 3.1 times and CO content in the gaseous combustion products by 40%, the scientists found. The research was published in Fuel Processing Technology.

According to the International Energy Agency (IEA), coal is the predominant energy resource used as the primary fuel for power generation. According to reports, coal supplied over one-third of global electricity generation in 2020. Experts believe that despite the generally accepted energy policy aimed at reducing the share of coal usage and switching to renewable energy sources, coal, as the main type of fuel in the world, will most likely still occupy a leading position in power generation in the coming years. However, the widespread use of coal is limited by a number of problems, such as incomplete combustion of fuel and concomitant formation of toxic gases. Taking this into account, development of technologies aiming at more effective and environmentally friendly coal thermal conversion is a priority task for the coal-fired power generation industry. One of the possible solutions to improve the coal-burning efficiency is the use of catalytically active agents, such as oxides of various metals and their precursors (salts based on nitrates, sulfates, acetates, and carbonates), to intensify the combustion process.

"It is too early to give up on coal. China, for instance, relies on coal as the primary energy source for much of the 21st century despite all the 'green' trends. In Russia, coal accounts for a little under 20% of the country's energy balance. Even in Great Britain, the country that's been consistently implementing its decarbonisation policy, the demand for coal by electricity generators was registered at over 200 thousand tons in the third quarter of 2020. It is safe to say that the search for catalytic additives for improved coal-burning efficiency will continue. For us, the search has been quite successful: the use of the additives proposed by our team has been proven to significantly improve coal-burning efficiency, especially with high-ash coals," noted Alexander Gromov, the NUST MISIS team lead and head of MISIS Catalysis Lab.

The method of coal combustion activation by metal salts is based on intensification of the combustion process and reduction of the combustion temperature. The use of the salt-based additives makes the combustion more manageable, the researchers note.

In their experiments, the scientists used copper salts as activating additives to improve reactivity of the high-ash coal fuels, such as anthracite, also known as hard coal, and semicoke. High-ash fuels are characterized by high minimum ignition and combustion temperatures, and low combustion intensity. The introduction of copper salts resulted in improved reactivity and higher burn rate of the fuel samples. It is also worth mentioning that the content of unburnt carbon in the ash residue of the modified samples was significantly lower than that in the reference samples.

The introduction of copper nitrates, acetates and sulfates to the fuel samples was carried out by the incipient wetness procedure. Ignition and combustion experiments were then performed in a combustion chamber at temperatures of the heating medium varying from 500 °C to 700 °C.

The mechanism of combustion activation relies on the intensification of the production of gas-phase combustion products at the early stage of volatiles' release and the generation of micro-explosions to prevent formation of slag layers that would otherwise block oxygen from the fuel.

When using oxide-based additives, dynamic contact between the fuel and the additive has to be ensured, the researchers noted. The use of salts as a catalyzing agent doesn't require that type of contact, which makes this new method of coal modifying potentially applicable in the energy industry.

The researchers believe that the use of salt-based additives for increasing the efficiency of coal-burning could help improve fuel efficiency in energy production, minimize energy use for preheating power generating equipment and reduce carbon emissions from coal-fired power plants.

FRANKFURT. The lens of the human eye gets its transparency and refractive power from the fact that certain proteins are densely packed in its cells. These are mainly crystallines. If this dense packing cannot be maintained, for example due to hereditary changes in the crystallines, the result is lens opacities, known as cataracts, which are the most common cause of vision loss worldwide.

In order for crystallins to be packed tightly in lens fibre cells, they must be folded stably and correctly. Protein folding already begins during the biosynthesis of proteins in the ribosomes, which are large protein complexes. Ribosomes help translate the genetic code into a sequence of amino acids. In the process, ribosomes form a protective tunnel around the new amino acid chain, which takes on three-dimensional structures with different elements such as helices or folded structures immediately after the tunnel's formation. The gamma-B crystallines studied in Frankfurt and Grenoble also exhibit many bonds between two sulphur-containing amino acids, so-called disulphide bridges.

The production of these disulphide bridges is not easy for the cell, since biochemical conditions prevail in the cell environment that prevent or dissolve such disulphide bridges. In the finished gamma-B crystalline protein, the disulphide bridges are therefore shielded from the outside by other parts of the protein. However, as long as the protein is in the process of formation, this is not yet possible.

But because the ribosomal tunnel was considered too narrow, it was assumed - also on the basis of other studies - that the disulphide bridges of the gamma-B crystallins are formed only after the proteins have been completed. To test this assumption, the researchers from Frankfurt and Grenoble used genetically modified bacterial cells as a model system, stopped the synthesis of the gamma-B crystallins at different points in time and examined the intermediate products with mass spectrometric, nuclear magnetic resonance spectroscopic and electron microscopic methods, and supplemented these with theoretical simulation calculations. The result: The disulphide bridges are already formed on the not yet finished protein during the synthesis of the amino acid chain.

"We were thus able to show that disulphide bridges can already form in the ribosomal tunnel, which offers sufficient space for this and shields the disulphide bridges from the cellular milieu," says Prof. Harald Schwalbe from the Institute of Organic Chemistry and Chemical Biology at Goethe University. "Surprisingly, however, these are not the same disulphide bridges that are later present in the finished gamma-B crystallin. We conclude that at least some of the disulphide bridges are later dissolved again and linked differently. The reason for this probably lies in the optimal timing of protein production: the 'preliminary' disulphide bridges accelerate the formation of the 'final' disulphide bridges when the gamma-B crystallin is released from the ribosome."

In further studies, the researchers now want to test whether the synthesis processes in the slightly different ribosomes of higher cells are similar to those in the bacterial model system.

Dramatic decreases in traffic caused by COVID-19 shutdowns improved air quality in car-dependent states but didn't offset additional forms of pollution in other parts of the country.

Those findings by a University of South Florida researcher suggest that while decreasing the number of vehicles on the road is a good first step toward creating cleaner air, additional measures aimed at reducing other sources of air pollution, such as coal plants or industrial factories, must also be considered.

The study, led by Yasin Elshorbany, an assistant professor of atmospheric chemistry and climate change at USF's St. Petersburg campus, was published in the journal, "Remote Sensing."

For the study, Elshorbany analyzed the impact of the pandemic-related lockdown on air quality by using remote sensors that measured different elements within the air, including nitrogen dioxide, carbon monoxide, ozone and aerosol particles. The study focused on states with high traffic volume, such as New York, Illinois, Florida, Texas and California.

The clear skies and empty roads caused by the COVID-19 lockdowns created a valuable research opportunity. The study found that vehicle volumes across the U.S. dropped by 40-60 percent shortly after the pandemic was declared.

The results showed a significant improvement in air quality in regions where traffic is the main pollution source, such as in New York City and the state of Florida. However, it was not as effective in areas dominated by other sources of pollution, including industrial emissions or meteorological conditions. In fact, in areas such as Charleston, WV, and Chicago, air quality actually worsened during the pandemic due to an increase in other pollution sources.

"This shows that in certain states, in addition to traffic regulations we need to focus on other big pollution problems, such as industrial emissions in Illinois, wildfires in California or oil refineries in Texas," Elshorbany added.

Elshorbany was interested in how significant the changes in air quality would be during the lockdown because enhanced environmental regulations related to tailpipe pollution were already leading to cleaner air in the U.S.

"With the advancements in technology and the use of catalysts in cars over the past few decades, air quality has improved in the U.S.," he said. "This has resulted in traffic not serving as the main pollutant in most of the country."

The study was funded by a $25,000 grant from USF Research & Innovation, one of 14 studies supported by nearly $320,000 in seed grants for COVID-19 research partnerships.

In addition to the current study, Elshorbany is working with a multidisciplinary team from USF to examine key environmental impacts brought about by the lockdown. Their goal is to better understand the health and socioeconomic consequences of changes in air quality.

"This demonstrates USF's commitment to timely and important research," Elshorbany said. "It gives us the opportunity to publish information that is relevant to policymakers and useful to everyday people."

The gram-negative bacteria Helicobacter pylori (H. pylori) colonize the stomachs of the majority of the world's population. Although most people may never experience major complications due to the pathogen, H. pylori infections increase the risk of certain types of gastric cancer, as well as other illnesses such as peptic ulcers and gastritis.

Currently, H. pylori infections are treatable with a cocktail of antibiotics, but the rapid emergence of antibiotic resistance in H. pylori is a significant concern. To counter these threats, Pushkar Lele, assistant professor in the Artie McFerrin Department of Chemical Engineering at Texas A&M University, investigated how H. pylori locate their ideal environment within a host's stomach.

Motile bacteria such as H. pylori swim by rotating string-like appendages called flagella. They navigate by sensing chemical signals in their environment, a process known as chemotaxis. An intracellular signaling pathway - the chemotaxis network - aids navigation by controlling the direction of rotation of the flagella. Current understanding of how the chemotaxis network operates is based on studies of Escherichia coli (E. coli), which is a model system for bacterial chemotaxis and motility. The chemotaxis network in E. coli modulates the probability of clockwise rotation in otherwise counterclockwise-rotating flagella to help the cell migrate toward favorable chemical environments. How the chemotaxis network modulates flagellar functions in H. pylori is not known.

Popular techniques that use probes to study chemotactic function in bacteria do not work well in H. pylori. This creates significant challenges in understanding flagellar functions in this species. To overcome these challenges, Lele's group pioneered a novel probe-free approach to study flagellar functions in H. pylori.

Their approach exploited the fact that cells swam around in clockwise circles near glass surfaces when their flagella rotated counterclockwise, and counterclockwise circles when their flagella rotated clockwise. In a paper published in eLife, Lele and his research team used this approach to report the probability of the clockwise rotation in H. pylori for the first time. Jyot Antani, a doctoral student in Lele's group, performed the experiments that further showed that H. pylori's chemotaxis network modulates flagellar functions similar to that in E. coli.

Lele said the similarity in the form of flagellar control in the two bacterial species is intriguing given that they differ in many key aspects. Whereas H. coli prefer the stomach, E. coli are found in the lower gastrointestinal tract. The physical characteristics of H. pylori are such that they run forward and reverse, unlike E. coli, which run forward and then tumble. As a result, the modulation of the probabilities of clockwise flagellar rotation, which suits E. coli very well, is predicted to cause errors in chemotaxis in H. pylori.

Lele predicts that future work with their new approach will reveal how H. pylori reach their targets despite the errors and how dietary interventions can be developed to inhibit chemotaxis.

SAN ANTONIO -- Humans possess a formidable multi-layered defense system that protects us against viral infections. Better understanding of these defenses and the tricks that viruses use to evade them could open novel avenues for treating viral infections and possibly other diseases.

For example, a human protein called SAMHD1 impedes replication of the human immunodeficiency virus (HIV) and other viruses by depleting deoxynucleotides ­­-- building blocks needed for the replication of the viral genome. It has long remained a mystery whether and how this protein is activated in response to infection.

Now researchers from The University of Texas Health Science Center at San Antonio (UT Health San Antonio) have discovered that SAMHD1 recognizes a unique molecular pattern in nucleic acids. This pattern, called "phosphorothioation," may act as a signal for action. It's like a sentinel atop a palace wall who sees an invading horde in the distance and calls the troops to battle stations.

Understanding the mechanism of SAMHD1 activation could be a step forward in the fight against HIV/AIDS.

"If we are able to increase SAMHD1 activity using a specific drug, that could potentially have anti-HIV activity," said Corey H. Yu, PhD, postdoctoral fellow in the laboratory of Dmitri Ivanov, PhD, at UT Health San Antonio.

Today's antivirals target the viral proteins. If, in addition, therapies could unleash the power of our existing immune defenses on the virus to help eliminate it from the body, that could be a game-changer.

"It's a different way to look at antiviral drugs," Dr. Yu said. "We want to know if we can try to target a protein to hopefully boost its activity against HIV."

Washington, February 10, 2021--After the COVID-19 crisis hit last March, federal student aid applications among potential college freshmen in California dropped 14 percent between mid-March and mid-August, relative to prior years. While there were also initial declines in applications among current undergraduates and graduate students, these quickly recovered and ended 8 percent higher relative to prior years. The findings, published today in Educational Researcher, a peer-reviewed journal of the American Educational Research Association, are from the first academic study conducted on this topic.

Using data from the California Student Aid Commission and the American Community Survey, study authors Oded Gurantz and Christopher Wielga, both at the University of Missouri, compared trends in the total volume and characteristics of submissions of the Free Application for Federal Student Aid (FAFSA) across California from mid-March through mid-August 2020, relative to three prior submission cycles, and analyzed individuals' background information to identify neighborhood income and ethnic characteristics.

The authors found a 21 percent decline in submissions among incoming first-year undergraduates with no prior college experience and a 7 percent decline among those with some prior experience. Increases in submissions among continuing students were directly tied to grade level, being the smallest for incoming sophomores (1.9 percent) and largest for students entering graduate programs (34.1 percent).

"COVID is tough and it makes sense that it may make potential first-year students feel they can't go to college, due to either overwhelming commitments or an understandable judgment that online education may not suit them in the short-term," said Gurantz, an assistant professor at the University of Missouri. "But we know that short-term stop-outs often harm long-term outcomes, and in the long run it's important that these students earn their degrees."

The authors noted that their findings parallel enrollment figures reported by the National Student Clearinghouse last fall that showed a decline in 2020 undergraduate enrollments nationally, and in California, driven by first-time students. The clearinghouse also found that the deepest enrollment drops were at two-year institutions--the type of institution chosen by most students who submitted FAFSAs during March through August in prior years, according to Gurantz.

When comparing neighborhood characteristics for FAFSA filers, Gurantz and Wielga found a 5 percent drop in applications from zip codes in the top third in terms of percentage of Black and Hispanic residents. In contrast, neighborhoods in the middle third for Black and Hispanic residents saw applications rise 4 percent. Neighborhoods in the lowest third for Black and Hispanic residents saw applications rise 10 percent.

Gurantz and Wielga found similar results with year-over-year declines in low-income zip codes and increases in high-income zip codes.

"Our results paint a bleak portrait, suggesting that without immediate investments in outreach and support, traditionally underrepresented students will be less likely to attend college and more likely to take on debt," Gurantz said. "More outreach is needed to make sure that missing students find their way to college, and that current students who are struggling get the support they need."

"The turmoil and economic uncertainty of the pandemic are creating substantial barriers to college entry, and the trend in FAFSA applications is likely to exacerbate enrollment gaps by income, race, and ethnicity," said Gurantz.

According to the authors, states could help increase FAFSA submissions by improving their early outreach to students, providing reminders, and flagging students who have not submitted by a specific date. The authors also suggest the federal government could consider simplifying the FAFSA process, reducing the number of individuals who are asked to verify their income through additional documentation after they submit their applications, or simplifying the appeals process. Extending deadlines for FAFSA submissions and college applications could also help to facilitate greater access. In January, the Education Department issued guidance to college financial aid administrators encouraging them to exercise their professional judgment to adjust financial aid eligibility based on a student's special circumstances.

"Providing additional funding to community colleges, which are experiencing the largest downturns in enrollment, may also be necessary," Gurantz said. "These institutions will be central to promoting the kinds of programs and resources needed to ensure that more of these missing students are successful over the coming years, should they choose to return."

NEWPORT, Ore. - Analyzing thousands of genetic markers in albacore tuna from the Pacific Ocean, researchers at Oregon State University have learned that just seven dozen of those markers are needed to determine which side of the equator a fish comes from.

The scientists also discovered that fish from different hemispheres intermingle and sometimes breed with each other.

Published Tuesday in Evolutionary Applications, the findings are an important step toward better understanding the population structure of a species that's a vital and inexpensive source of protein for people around the globe.

Albacore in the North and South Pacific Oceans are currently managed as separate stocks. The OSU study affirms this approach while also opening the door to more research into overlap and interbreeding that can be used to refine management strategies throughout the Pacific.

"Albacore support one of the world's largest and most valuable fisheries and one that is particularly important on the west coast of North America," said Kathleen O'Malley, an associate professor in the OSU College of Agricultural Sciences. "There's been a lot of work done to understand stock structure of the albacore globally, but research in the Pacific hasn't been very fine-tuned and has tended to generate as many questions as answers."

O'Malley, who is also the fisheries geneticist for the state of Oregon, noted that previous research involving tagged fish has revealed no movement of albacore from one side of the equator to the other. At the same time, previous genetic data have yielded no way to tell if a fish was from the North Pacific or South Pacific - hence the lack of understanding regarding the connectivity between the two populations.

O'Malley and postdoctoral research associate Felix Vaux, who led the study, looked at DNA from 308 fish from 12 locales around the Pacific. They identified nearly 13,000 genetic markers - DNA sequences with known physical locations on chromosomes - and learned that fewer than 100 of those markers told the tale of what part of the ocean a fish came from.

"We identified 12,872 markers and were able to discriminate between North and South Pacific albacore by using only 84 of them," Vaux said.

Those 84, he added, appear to be "under selection" and may reflect adaptive differences between the two albacore stocks. In any population, individuals with locally adapted traits tend to be the most successful reproductively, meaning that over time selection will increase the prevalence of those traits. With continuing, intense selection, adaptive traits become universal or close to it in a population or species.

"There is no complete genome for albacore to compare our data against, so we weren't able to determine which genes underlie these likely adaptive differences," O'Malley said. "In addition, we found that some fish have mixed genetic backgrounds - indicating that albacore from the North and South Pacific sometimes spawn at the same time and place and breed together. Also, we detected albacore with South Pacific genetic profiles in the North Pacific, providing evidence for migration across the equator that had earlier gone undetected via physical tagging data."

Future studies, she added, will use these genetic markers to more deeply investigate interbreeding between North and South Pacific albacore as well as migration between hemispheres.

O'Malley, who directs the State Fisheries Genomics Lab at OSU's Hatfield Marine Science Center, says that both genetic and demographic connectivity, while important for effective management and conservation strategies, are not well understood in most marine species.

Genetic diversity is an important tool for populations trying to adapt to climate change and other environmental perturbances, she said. With more variation, it is more likely that some individuals in a population will be suited to withstand the changes and produce offspring that are also able to thrive in the modified environment.

A study published in Nature Communications today (Wednesday 10 February) presents a compelling new evidence about what a key protein called alpha-synuclein actually does in neurons in the brain.

Dr Giuliana Fusco, Research Fellow at St John's College, University of Cambridge, and lead author of the paper, said: "This study could unlock more information about this debilitating neurodegenerative disorder that can leave people unable to walk and talk. If we want to cure Parkinson's, first we need to understand the function of alpha-synuclein, a protein present in everyone's brains. This research is a vital step towards that goal."

Parkinson's disease is a progressive neurological disorder that causes nerve cells in the brain to weaken or die. The disease has a variety of symptoms including tremors - particularly in the hands - gait and balance problems, slowness and extreme stiffness in the arms and legs. Parkinson's develops when cells in the brain stop working properly and can't produce enough dopamine, a chemical that control's movement in the body by acting as a messenger between cells.

The disease mostly affects people over 60 and gets worse over a number of years but early onset Parkinson's can affect people even younger.

More than 10 million people worldwide live with Parkinson's disease including actor Michael J. Fox who was diagnosed aged 29, singer Neil Diamond, comedian Billy Connolly and musician Ozzy Osbourne. Parkinson's can affect women, but men are more likely to have the disease.

It is not yet known why people get Parkinson's, but researchers think it's a combination of age, genetic and environmental factors that cause the dopamine-producing nerve cells to die affecting the body's ability to move.

The new study looked at what was going on inside healthy conditions to help pinpoint what is going wrong in the cells of people with Parkinson's. All cells in the body have a plasma membrane that protects cells and usually transports nutrients in, and clears toxic substances out.

Dr Fusco explained: "One of the top questions in Parkinson's research is: what is the function of alpha-synuclein, the protein that under pathological conditions forms clumps that affect motor and cognitive abilities? Usually you discover a protein for its function and then you explore what is going wrong when disease strikes, in the case of alpha-synuclein the protein was identified for its pathological association but we didn't know what it did in the neuron. Our research suggests that the alpha-synuclein protein sticks like glue to the inner face of the plasma membrane of nerve cells but not to the outer- a crucial new piece of information."

The scientists used synthetic models to mimic brain cells membranes during the study.

Professor Alfonso De Simone, from Imperial College London and one of the authors of the paper, said: "When this protein is functioning normally it plays an important part in the mechanisms by which neurons exchange signals in the brain. But it has a dark side because it malfunctions and begins to stick together in clumps which eventually spread and kill healthy brain cells. Our research showed that this protein clings onto the inner face of the plasma membrane of brain cells so we are slowly building a picture of this very complex disorder by studying the key function of alpha-synuclein."

There are treatments and drugs available to Parkinson's patients and the disease isn't fatal, but nothing is available to reverse the effects of the disease. Introducing lifestyle changes including getting more rest and exercise can also alleviate symptoms.

Professor De Simone added: "We have thousands of proteins in our bodies and until the function of this mystery protein is confirmed with more research, drug therapies cannot begin to be developed to tackle the origins of Parkinson's Disease in case medication accidentally affect a crucial purpose of the alpha-synuclein protein."

In nature, as in everyday life, we are surrounded by resonance - the phenomenon that describes how each object has a frequency that it prefers to vibrate at. The note of a guitar string and the sound of Big Ben chiming are examples of resonance.

Vibrations near resonance cause strong impacts. Bridges collapse if soldiers march in unison; a kid can 'push' themselves on a swing by moving their legs at the correct rate, and two pendulum clocks on the same table will synchronise. These examples show the enhanced sensitivity given to an object when it is provided with energy at a specific (that is, resonant) frequency. It's no wonder then that physicists and engineers are always looking for ways to use resonance to trigger useful effects and strong responses by applying the smallest amount of energy.

Now, a team of physicists from the University of Bath has found a way to use resonance to harness the energy of light more effectively inside structures called microresonators. For light, microresonators act as miniature racetracks, with photons zipping around the circle in loops. Light consists of photons of different colours, with each colour corresponding to waves oscillating at specific wavelengths and frequencies. If the peaks of these waves reach the same point after a full loop is made around the resonator, then the energy storage capacity of the resonator hits a maximum when measured against frequency. In other words, the resonator and the light inside come to resonance.

The ability of a resonator to store energy is characterised by the sharpness of the resonance, also called finesse.

Physicists are caught in a race to maximise the finesses of resonators, so as to store as much energy as possible in a single resonator. The reason for this is not just bragging rights. When high light energy is circulating in a resonator, it starts to reveal interesting properties. For instance, the resonator begins to produce photons of light with new frequencies and therefore of different colours.

A newly created rainbow of colours is known as a frequency comb. A comb's many useful properties led to researchers working on 'the optical frequency comb technique' winning the 2005 Nobel Prize in Physics. Unlike a sky rainbow, the one created in a resonator doesn't display a continuous spectrum of colours. Instead, it contains a regular and equally spaced pattern of colours, similar to the teeth on a comb. The regularity of these teeth allows these combs to be used for ultra-precise measurements - for instance, of distances and time.

The University of Bath study has found that boosting the strength of light matter interactions to make frequency combs is not the only reasons high-finesse microresonators are important. If finesse is relatively small, then tuning a laser around one of the resonances causes a given comb tooth to adjust its colour continuously. Reaching finesses of several thousands and into tens of thousands, however, starts to break this continuity.

When the continuity is broken, a laser tuned to generate a pair of photons with two specific colours will need to pass through the 'idle interval' before the next colour becomes ignited. During this interval, there can be no conversion into new colours.

In the language of resonance theory, the interval creation is called Arnold tongues. Arnold tongues is a phenomenon often found in networks of oscillators. The neurons in our brains work according to the rules of Arnold tongues to synchronise the transmission of signals.

The microresonator tongues reported in the Bath study represent a map of the narrow tongue-like structures that shows how laser parameters should be tuned to either generate or not generate new colours.

The photon pair generation process is a key phenomenon underpinning the development of tunable light sources for various applications, and in particular for optical data processing and transmission. Discovering the connection between photon-pair generation and Arnold tongues is expected to boost the efficiency of this process. Further increasing of finesses is possible by freezing the microresonators to a temperature where the molecules it is made from stop vibrating. This is expected to trigger new ways to manipulate photons, and the Bath team plans to study these next.

Professor Dmitry Skryabin from Bath's Centre for Photonics and Photonic Materials, and lead researcher on this study, said, "Since the 2005 Nobel Prize, the comb technology has rapidly downscaled to the size of computer chips. This means miniaturised frequency comb generators can have myriads of diverse applications in for example pollution monitoring, radar technology, and discovering of new planets."

The high stakes of first dates require would-be partners to make and interpret first impressions. But, can we rely on these first impressions to accurately assess someone's personality? According to researchers from McGill University, the answer is yes, although it may be more difficult than in more casual settings.

Forming an accurate impression of an individual on a first date is important because people often rely on these impressions in deciding whether to pursue a romantic relationship. While previous studies have shown that people can form accurate impressions of new acquaintances in platonic settings - like casual conversations with new classmates - the researchers wanted to find out if the same was true for higher-stakes situations like first dates.

To find answers, they invited 372 participants to partake in speed-dating events in Montreal in 2017 and 2018. Participants were asked to complete a questionnaire assessing their personality and well-being. A close friend or family member also completed a questionnaire on the participant's personality. Participants then had a series of brief, three-minute first dates; after each interaction, they rated their date's personality.

On average, people did see their dates' personalities accurately, but some dates were easier to read than others. "Some people are open books whose distinctive personalities can be accurately perceived after a brief interaction, whereas others are harder to read," says co-author Lauren Gazzard Kerr, a PhD student in the Department of Psychology at McGill University under the supervision of Professor Lauren Human. "Strikingly, people who report higher well-being, self-esteem, and satisfaction with life tend to make the task easier," she says.

Why are some people easier to read?

The researchers note that one explanation could be that some individuals engage in more effective self-presentation. "Perhaps people that have greater well-being behave in ways that are more in line with their personality - being more authentic or true to themselves," says Assistant Professor Lauren Human. In a previous study, the researchers also found evidence of this in platonic settings.

Alternatively, it may be that people who are perceived more accurately come to experience greater well-being - not necessarily that greater well-being leads to being perceived more accurately. Both are plausible, according to Human.

As next steps, the researchers hope to explore why those who report greater well-being are seen more accurately on first dates. The researchers will also examine the consequences of accurate first impressions and how they influence romantic interest.

"Understanding why some people are able to be seen more accurately could help us determine strategies that other people could apply to enhance how accurately they are perceived," says Human.

Russian researchers from HSE University have studied a hypothesis regarding the capability of the visual system to automatically categorize objects (i.e., without requiring attention span). The results of a simple and beautiful experiment confirmed this assumption. The paper was published in the journal Scientific Reports. The study was supported by a Russian Science Foundation grant.

Humans receive a lot of information from the environment through their vision. Every day, we face a flow of varied visual stimuli. At the same time, information processing requires cognitive resources. Like a computer processor, the human brain has limited capacity in terms of the data it is able to process and save in its memory. One hypothesis states that the visual system somehow 'decreases files' resolution in order to avoid overloading. As a result of such 'compression', instead of a detailed analysis of the observed objects, the visual system categorizes them by simple general attributes, such as size. Later, such 'primary data' can be used for a more thorough analysis.

Researchers sought to answer the following question: is the visual system capable of automatic object categorization (i.e., without attention)? In their study, the researchers tried to determine the conditions in which such automatic categorization would work. They used the visual mismatch negativity (vMMN) component measured by electroencephalography (EEG) as a marker of automatic sensory discrimination. vMMN shows the difference between the brain's reactions to a standard (frequent) or a deviant (rare) stimulus. vMMN demonstrates that the visual system noticed a difference between stimuli and, importantly, that it did so without requiring attention.

'We are very interested and amazed by the human visual system's ability to categorize high numbers of objects. For example, when humans look at an apple tree, they immediately differentiate apples from leaves. This study shows that the process of quick categorization can be performed automatically based on the information on differences between objects', says Vladislav Khvostov, Junior Research Fellow at the HSE Laboratory for Cognitive Research, School of Psychology, one of the paper's authors.

To study the automatic distribution of objects into groups using vMMN, the researchers conducted a simple experiment with a fillertask. Study participants were asked to look at a small asymmetrical cross in the centre of the field and press the button each time the cross changed its orientation. This way, the participants' attention was focused on the position of the cross in the centre of the field. The cross was surrounded by rows of lines of varied lengths and orientation. In each experiment block, the combination of these parameters was different. While the participants' attention was focused on the central figure, the researchers used EEG to record brain activity in response to background visual stimulation. In each block of the experiment, the participants were shown 700 visual stimuli, each of which was presented on the screen for 200 ms followed by 400 ms of empty screen. Most of the stimuli included a fixed combination of lines' length and orientation (for example, long lines were steep, and short ones were flat), but in 10% of cases, the combination of parameters was the opposite.

According to Vladislav Khvostov, the only task for the participants was to press a button when the central cross rotated (third image from the left). In the image above, the central cross size is magnified for illustrational purposes. Together with the cross, the participants observed a background visual stimulation consisting of lines with different lengths and orientations. In most cases (standard stimuli) the combination of length and orientation was the same: long lines were flat, and short ones were steep, but in very rare cases (deviant stimuli, seventh image) this combination changed to the opposite: long lines became steep, while short ones became flat. The participants did not pay attention to the change of stimuli, but analysis of EEG indicators showed that the visual system tracked these changes as well.

The researchers were interested in the brain's reaction to the replacement of a standard stimulus with a deviant one. If the feature had only two peak values (short/long in case of length; vertical/horizontal in case of orientation), it was called 'segmentable'. If the attribute had interim values, it was defined as 'non-segmentable.'

The researchers found considerable visual mismatch negativity in response to a deviant stimulus in cases when either both of the features were segmentable, or only length was. Since on all stimuli inside each block, the distribution of lengths and orientations remained constant, the researchers concluded that categorization was not made by one simple feature. This means that the visual system categorized the lines by their combinations. In their experiment, the researchers thus contradicted the assumption that the visual system categorizes the objects only by simple feature. It can solve a less trivial version of the task and use combinations of features.

DNA sequences that can fold into shapes other than the classic double helix tend to have higher mutation rates than other regions in the human genome. New research shows that the elevated mutation rate in these sequences plays a major role in determining regional variation in mutation rates across the genome. Deciphering the patterns and causes of regional variation in mutation rates is important both for understanding evolution and for predicting sites of new mutations that could lead to disease.

A paper describing the research by a team of Penn State scientists is available online in the journal Nucleic Acids Research.

"Most of the time we think about DNA as the classic double helix; this basic form is referred to as 'B-DNA,'" said Wilfried Guiblet, co-first author of the paper, a graduate student at Penn State at the time of research and now a postdoctoral scholar at the National Cancer Institute. "But, as much as 13% of the human genome can fold into different conformations called 'non-B DNA.' We wanted to explore what role, if any, this non-B DNA played in variation that we see in mutation rates among different regions of the genome."

Non-B DNA can fold into a number of different conformations depending on the underlying DNA sequence. Examples include G-quadruplexes, Z-DNA, H-DNA, slipped strands, and various other conformations. Recent research has revealed that non-B DNA plays critical roles in cellular processes, including the replication of the genome and the transcription of DNA into RNA, and that mutations in non-B sequences are associated with genetic diseases.

"In a previous study, we showed that in the artificial system of a DNA sequencing instrument, which uses similar DNA copying processes as in the cell, error rates were higher in non-B DNA during polymerization," said Kateryna Makova, Verne M. Willaman Chair of Life Sciences at Penn State and one of the leaders of the research team. "We think that this is because the enzyme that copies DNA during sequencing has a harder time reading through non-B DNA. Here we wanted to see if a similar phenomenon exists in living cells."

The team compared mutation rates between B- and non-B DNA at two different timescales. To look at relatively recent changes, they used an existing database of human DNA sequences to identify individual nucleotides--letters in the DNA alphabet--that varied among humans. These 'single nucleotide polymorphisms' (SNPs) represent places in the human genome where at some point in the past a mutation occurred in at least one individual. To look at more ancient changes, the team also compared the human genome sequence to the genome of the orangutan.

They also investigated multiple spatial scales along the human genome, to test whether non-B DNA influenced mutation rates at nucleotides adjacent to it and further away.

"To identify differences in mutation rates between B- and non-B DNA we used statistical tools from 'functional data analysis' in which we compare the data as curves rather than looking at individual data points," said Marzia A. Cremona, co-first author of the paper, a postdoctoral researcher at Penn State at the time of the research and now an assistant professor at Université Laval in Quebec, Canada. "These methods give us the statistical power to contrast mutation rates for the various types of non-B DNA against B-DNA controls."

For most types of non-B DNA, the team found increased mutation rates. The differences were enough that non-B DNA mutation rates impacted regional variation in their immediate surroundings. These differences also helped explain a large portion of the variation that can be seen along the genome at the scale of millions of nucleotides.

"When we look at all the known factors that influence regional variation in mutation rates across the genome, non-B DNA is the largest contributor," said Francesca Chiaromonte, Huck Chair in Statistics for the Life Sciences at Penn State and one of the leaders of the research team. "We've been studying regional variation in mutation rates for a long time from a lot of different angles. The fact that non-B DNA is such a major contributor to this variation is an important discovery."

"Our results have critical medical implications," said Kristin Eckert, professor of pathology and biochemistry and molecular biology at Penn State College of Medicine, Penn State Cancer Institute Researcher, an author on the paper, and the team's long-time collaborator. "For example, human geneticists should consider the potential of a locus to form non-B DNA when evaluating candidate genetic variants for human genetic diseases. Our current and future research is focused on unraveling the mechanistic basis behind the elevated mutation rates at non-B DNA."

The results also have evolutionary implications.

"We know that natural selection can impact variation in the genome, so for this study we only looked at regions of the genome that we think are not under the influence of selection," said Yi-Fei Huang, assistant professor of biology at Penn State and one of the leaders of the research team. "This allows us to establish a baseline mutation rate for each type of non-B DNA that in the future we could potentially use to help identify signatures of natural selection in these sequences."

Because of their increased mutation rates, non-B DNA sequences could be an important source of genetic variation, which is the ultimate source of evolutionary change.

"Mutations are usually thought to be so rare, that when we see the same mutation in different individuals, the assumption is that those individuals shared an ancestor who passed the mutation to them both," said Makova, a Penn State Cancer Institute researcher. "But it's possible that the mutation rate is so high in some of these non-B DNA regions that the same mutation could occur independently in several different individuals. If this is true, it would change how we think about evolution."