Culture

New Rochelle, NY, February 25, 2020--A new study has shown that experiencing personalized experiences in a virtual reality setting can improve affect among university students. The study, which also showed that the use of personalized 360 video experiences is feasible for use in hospitalized patients to improve affect, is published in Cyberpsychology, Behavior, and Social Networking, a peer-reviewed journal from Mary Ann Liebert, Inc., publishers. Click here to read the full-text article free on the Cyberpsychology, Behavior, and Social Networking website through March 25, 2020.

Christopher Evans, Elodie Chiarovano, and Hamish MacDougall, University of Sydney, Australia, coauthored the article entitled "The Potential Benefits of Personalized 360 Video Experiences on Affect: A Proof-of-Concept Study." Poor affect can worsen the outcomes for patients in long-term hospital or institutionalized settings. Although these patients may not be able to attend events or visit with family that could improve their affect, they could possibly do so in a virtual reality setting through 360 video experiences.

The researchers found the virtual reality intervention to target negative affect levels, and those with high levels of negative affect benefited the most from the 360 video experiences. After testing the intervention on a population of university students, the researchers demonstrated the feasibility of using it in a hospitalized patient, enabling the patient to virtually attend an important life event. The patient had an increase in positive affect and a decrease in negative affect, with no side effects.

"Virtual reality may benefit hospitalized patients as well as those who are in long-term care facilities or those who have difficulties traveling. With increasing age, travel can become more difficult and VR may offer the opportunity for inclusion of family members and loved ones no matter their location, enriching important social occasions and family gatherings, and further improving quality of life," says Editor-in-Chief Brenda K. Wiederhold, PhD, MBA, BCB, BCN, Interactive Media Institute, San Diego, California and Virtual Reality Medical Institute, Brussels, Belgium

Among the most exciting challenges in modern physics is the identification of the neutrino mass ordering. Physicists from the Cluster of Excellence PRISMA+ at Johannes Gutenberg University Mainz (JGU) play a leading role in a new study that indicates that the puzzle of neutrino mass ordering may finally be solved in the next few years. This will be thanks to the combined performance of two new neutrino experiments that are in the pipeline - the Upgrade of the IceCube experiment at the South Pole and the Jiangmen Underground Neutrino Observatory (JUNO) in China. They will soon give the physicists access to much more sensitive and complementary data on the neutrino mass ordering.

Neutrinos are the chameleons among elementary particles

Neutrinos are produced by natural sources - in the interior of the sun or other astronomical objects, for example - but also in vast quantities by nuclear power plants. However, they can pass through normal matter - such as the human body - practically unhindered without leaving a trace of their presence. This means that extremely complex methods requiring the use of massive detectors are needed to observe the occasional rare reactions in which these 'ghost particles' are involved.

Neutrinos come in three different types: electron, muon and tau neutrinos. They can change from one type to another, a phenomenon that scientists call 'neutrino oscillation'. It is possible to determine the mass of the particles from observations of the oscillation patterns. For years now, physicists have been trying to establish which of the three neutrinos is the lightest and which is the heaviest. Prof. Michael Wurm, a physicist at the PRISMA+ Cluster of Excellence and the Institute of Physics at JGU, who is playing an instrumental role in setting up the JUNO experiment in China, explains: "We believe that answering this question will contribute significantly towards enabling us to gather long-term data on the violation of matter-antimatter symmetry in the neutrino sector. Then, using this data, we hope to find out once and for all why matter and anti-matter did not completely annihilate each other after the Big Bang."

Global cooperation pays off

Both large-scale experiments use very different and complementary methods in order to solve the puzzle of the neutrino mass ordering. "An obvious approach is to combine the expected results of both experiments," points out Prof. Sebastian Böser, also from the PRISMA+ Cluster of Excellence and the Institute of Physics at JGU, who researches neutrinos and is a major contributor to the IceCube experiment.

No sooner said than done. In the current issue of the journal Physical Review D, researchers from the IceCube and the JUNO collaboration have published a combined analysis of their experiments. For this, the authors simulated the predicted experimental data as a function of the measuring time for each experiment. The results vary depending on whether the neutrino masses are in their normal or reversed (inverted) order. Next, the physicists carried out a statistical test, in which they applied a combined analysis to the simulated results of both experiments. This revealed the degree of sensitivity with which both experiments combined could predict the correct order, or rather rule out the wrong order. As the observed oscillation patterns in JUNO and IceCube depend on the actual neutrino mass ordering in a way specific to each experiment, the combined test has a discriminating power significantly higher than the individual experimental results. The combination will thus permit to definitively rule out the incorrect neutrino mass ordering within a measuring period of three to seven years.

"In this case, the whole really is more than the sum of its parts," concludes Sebastian Böser. "Here we have clear evidence of the effectiveness of a complementary experimental approach when it comes to solving the remaining neutrino puzzles." "No experiment could achieve this by itself, whether it's the IceCube Upgrade, JUNO or any of the others currently running," adds Michael Wurm. "Moreover it just shows what neutrino physicists here in Mainz can achieve by working together."

An international team of scientists from ITMO University and George Washington University (USA) created an algorithm for studying the evolutionary history of species with whole-genome duplications, chiefly yeast and plants.

The program can be used to analyze the genetic information about these species and make conclusions on how whole-genome duplication took place and why it secured a foothold in the process of evolution. The article was published in Oxford Bioinformatics, one of the leading titles in the field of Computer Science.

According to research by genetic scientists, some plants and even mammals have whole-genome duplications, i.e. some of their genes exist in several copies that are more or less similar to each other. ?he ancestral genome didn't have such duplicates, but the duplication happened at some point of its evolutionary history and got a foothold in the population.

In order to understand the process of genome duplication, you have to create the so-called evolutionary history of a species with this evolutionary event. This history allows to track what happened with the population in the past and identify when exactly the duplication happened and how it got a foothold.

When attempting to create an evolutionary history with whole-genome duplications, a scientist has to face a series of tasks that are similar in their goals but have completely different mathematical structure. In order to solve them efficiently, you need optimization. For this purpose, a team that included specialists from ITMO University and the George Washington University (USA) proposed integer linear programming approach that were first proposed by Leonid Kantorovich, a Soviet mathematician, economist and the Nobel Memorial Prize in Economic Sciences.

"There's a class of tasks that are essentially similar but different from the standpoint of mathematics, explains Nikita Alekseev, co-author of the research, ITMO University. So we've developed a common approach that comes down to integer linear programming. This is an optimization method that reduces a complex program to a set of linear constraints for which there exists a selection of effective solvers."

As a result, the scientists developed a program that analyses duplicated genomes and makes presumptions on a species' evolutionary path, the number of genome duplications that took place in that time, and how the copies of genes that emerge as result of duplication changed. Sometimes mutations take place in them, changes in specific regions, so they are no longer identical.

This approach can also be applied for studying duplicated genome regions in animals.

"Genome duplications are present in many species and can affect not just the genome as a whole but also its fragments, and our tool can be adapted for solving such problems, too," concludes Nikita Alekseev.

About 1 million people in the United States have ulcerative colitis, a serious disease of the colon that has no cure and whose cause is obscure. Now, a study by Stanford University School of Medicine investigators has tied the condition to a missing microbe.

The microbe makes metabolites that help keep the gut healthy.

"This study helps us to better understand the disease," said Aida Habtezion, MD, associate professor of gastroenterology and hepatology. "We hope it also leads to our being able to treat it with a naturally produced metabolite that's already present in high amounts in a healthy gut."

When the researchers compared two groups of patients -- one group with ulcerative colitis, the other group with a rare noninflammatory condition -- who had undergone an identical corrective surgical procedure, they discovered that a particular family of bacteria was depleted in patients with ulcerative colitis. These patients also were deficient in a set of anti-inflammatory substances that the bacteria make, the scientists report.

A paper describing the research findings will be published online Feb. 25 in Cell Host & Microbe. Habtezion is the senior author. Lead authorship is shared by Sidhartha Sinha, MD, assistant professor of gastroenterology and hepatology, and postdoctoral scholar Yeneneh Haileselassie, PhD.

The discoveries raise the prospect that supplementing ulcerative colitis patients with those missing metabolites -- or perhaps someday restoring the gut-dwelling bacteria that produce them -- could effectively treat intestinal inflammation in these patients and perhaps those with a related condition called Crohn's disease, Habtezion said.

A clinical trial to determine whether those metabolites, called secondary bile acids, are effective in treating the disease is now underway at Stanford. Sinha is the trial's principal investigator, and Habtezion is the co-principal investigator.

Surgery often required

Ulcerative colitis is an inflammatory condition in which the immune system attacks tissue in the rectum or colon. Patients can suffer from heavy bleeding, diarrhea, weight loss and, if the colon becomes sufficiently perforated, life-threatening sepsis.

There is no known cure. While immunosuppressant drugs can keep ulcerative colitis at bay, they put patients at increased risk for cancer and infection. Moreover, not all patients respond, and even when an immunosuppressant drug works initially, its effectiveness can fade with time. About one in five ulcerative colitis patients progress to the point where they require total colectomy, the surgical removal of the colon and rectum, followed by the repositioning of the lower end of the small intestine to form a J-shaped pouch that serves as a rectum.

These "pouch patients" can lead quite normal lives. However, as many as half will develop pouchitis, a return of the inflammation and symptoms they experienced in their initial condition.

The new study began with a clinical observation. "Patients with a rare genetic condition called familial adenomatous polyposis, or FAP, are at extremely high risk for colon cancer," Habtezion said. "To prevent this, they undergo the exact same surgical procedure patients with refractory ulcerative colitis do." Yet FAP pouch patients rarely if ever experience the inflammatory attacks on their remaining lower digestive tract that ulcerative-colitis patients with a pouch do, she said.

The Stanford scientists decided to find out why. Their first clue lay in a large difference in levels of a group of substances called secondary bile acids in the intestines of seven FAP patients compared with 17 patients with ulcerative colitis who had undergone the pouch surgery. The investigators measured these metabolite levels by examining the participants' stool samples.

Primary bile acids are produced in the liver, stored in the gallbladder and released into the digestive tract to help emulsify fats. The vast majority of secreted primary bile acids are taken up in the intestine, where resident bacteria perform a series of enzymatic operations to convert them to secondary bile acids.

Prior research has suggested, without much elaboration or follow-up, that secondary bile acids are depleted in ulcerative colitis patients and in those with a related condition, Crohn's disease, in which tissue-destroying inflammation can occur in both the colon and the small intestine.

The researchers confirmed that levels of the two most prominent secondary bile acids, deoxycholic acid and lithocholic acid, were much lower in stool specimens taken from the ulcerative colitis pouch patients than from FAP pouch patients. Clearly, the surgical procedure hadn't caused the depletion.

Diminished microbial diversity

These findings were mirrored by the scientists' observation that microbial diversity in the specimens from ulcerative colitis pouch patients was diminished. Moreover, the investigators showed that a single bacterial family -- Ruminococcaceae -- was markedly underrepresented in ulcerative colitis pouch patients compared with FAP pouch patients. A genomic analysis of all the gut bacteria in the participants showed that the genes for making enzymes that convert primary bile acids to secondary bile acids were underrepresented, too. Ruminococcaceae, but few other gut bacteria, carry those genes.

"All healthy people have Ruminococcaceae in their intestines," Habtezion said. "But in the UC pouch patients, members of this family were significantly depleted."

Incubating primary bile acids with stool samples from FAP pouch patients, but not from ulcerative colitis pouch patients, resulted in those substances' effective conversion to secondary bile acids.

In three different mouse models of colitis, supplementation with lithocholic acid and deoxycholic acid reduced infiltration by inflammatory immune cells and levels of several inflammatory signaling proteins and chemicals in the mice's intestines, the researchers showed. The supplements also mitigated the classic symptoms of colitis in the mice, such as weight loss or signs of colon pathology.

All three mouse models are considered representative of not just ulcerative colitis but inflammatory bowel disease in general, a category that also includes Crohn's disease. So the findings may apply to Crohn's disease patients, as well, Habtezion said.

In an ongoing Phase 2 trial at Stanford, Sinha, Habtezion and their colleagues are investigating the anti-inflammatory effects, in 18- to 70-year-old ulcerative colitis pouch patients, of oral supplementation with ursodeoxycholic acid, a naturally occurring secondary bile acid approved by the Food and Drug Administration for treatment of primary biliary sclerosis and for management of gall stones. Information about the trial, which is still recruiting people, is available at https://clinicaltrials.gov/ct2/show/NCT03724175.

WASHINGTON, February 25, 2020 -- A new type of battery combines negative capacitance and negative resistance within the same cell, allowing the cell to self-charge without losing energy, which has important implications for long-term storage and improved output power for batteries.

These batteries can be used in extremely low-frequency communications and in devices such as blinking lights, electronic beepers, voltage-controlled oscillators, inverters, switching power supplies, digital converters and function generators, and eventually for technologies related to modern computers.

In Applied Physics Reviews, from AIP Publishing, Helena Braga and colleagues at the University of Porto in Portugal and the University of Texas at Austin, report making their very simple battery with two different metals, as electrodes and a lithium or sodium glass electrolyte between them.

"The glass electrolyte we developed was lithium-rich, and so I thought that we could make a battery in which the electrolyte would feed both electrodes with lithium ions, on charge and discharge with no need for lithium metal," said Braga.

This work is significant, because it unifies the theory behind all solid-state devices -- such as batteries, capacitors, photovoltaics and transistors - where the different materials in electrical contact exhibit the properties of the combined material instead of those of the individual materials.

"When one of the materials is an insulator or dielectric, such as an electrolyte, it will locally change its composition to form capacitors that can store energy and align the Fermi levels within the device," said Braga.

In a battery, the open circuit potential difference between electrodes is due to an electrical need to align the Fermi levels, a measure of the energy of the least tightly held electrons within a solid, which is also responsible for the polarity of the electrodes. The chemical reactions come later and are fed by this electrical potential energy stored in the capacitors.

"Our electrochemical cells, which in principle are simpler than batteries, are all about self-organization, which is the substance of life," Braga said.

To contribute to a more sustainable world, self-cycling can be stopped or mitigated by not allowing a leap in the Fermi levels or by configuring a negative resistance to happen.

"This can be obtained by having the negative electrode of the same material as the positive ions of the electrolyte," said Braga. "It gives rise to a device that self-charges without self-cycling -- increasing the energy stored in it -- as opposed to the natural degradation of the electrochemical process that makes the energy stored decrease by dissipation of heat. The latter has applications in all energy storage devices, such as batteries and capacitors, and can substantially improve their autonomy."

The Toba super-eruption was one of the largest volcanic events over the last two million years, about 5,000 times larger than Mount St. Helen's eruption in the 1980s. The eruption occurred 74,000 years ago on the island of Sumatra, Indonesia, and was argued to have ushered in a "volcanic winter" lasting six to ten years, leading to a 1,000 year-long cooling of the Earth's surface. Theories purported that the volcanic eruption would have led to major catastrophes, including the decimation of hominin populations and mammal populations in Asia, and the near extinction of our own species. The few surviving Homo sapiens in Africa were said to have survived by developing sophisticated social, symbolic and economic strategies that enabled them to eventually re-expand and populate Asia 60,000 years ago in a single, rapid wave along the Indian Ocean coastline.

Fieldwork in southern India conducted in 2007 by some of this study's authors challenged these theories, leading to major debates between archaeologists, geneticists and earth scientists about the timing of human dispersals Out of Africa and the impact of the Toba super-eruption on climate and environments. The current study continues the debate, providing evidence that Homo sapiens were present in Asia earlier than expected and that the Toba super-eruption wasn't as apocalyptic as believed.

The Toba volcanic super-eruption and human evolution

The current study reports on a unique 80,000 year-long stratigraphic record from the Dhaba site in northern India's Middle Son Valley. Stone tools uncovered at Dhaba in association with the timing of the Toba event provide strong evidence that Middle Palaeolithic tool-using populations were present in India prior to and after 74,000 years ago. Professor J.N. Pal, principal investigator from the University of Allahabad in India notes that "Although Toba ash was first identified in the Son Valley back in the 1980s, until now we did not have associated archaeological evidence, so the Dhaba site fills in a major chronological gap."

Professor Chris Clarkson of the University of Queensland, lead author of the study, adds, "Populations at Dhaba were using stone tools that were similar to the toolkits being used by Homo sapiens in Africa at the same time. The fact that these toolkits did not disappear at the time of the Toba super-eruption or change dramatically soon after indicates that human populations survived the so-called catastrophe and continued to create tools to modify their environments." This new archaeological evidence supports fossil evidence that humans migrated out of Africa and expanded across Eurasia before 60,000 years ago. It also supports genetic findings that humans interbred with archaic species of hominins, such as Neanderthals, before 60,000 years ago.

Toba, climate change and human resilience

Though the Toba super-eruption was a colossal event, few climatologists and earth scientists continue to support the original formulation of the "volcanic winter" scenario, suggesting that the Earth's cooling was more muted and that Toba may not have actually caused the subsequent glacial period. Recent archaeological evidence in Asia, including the findings unearthed in this study, does not support the theory that hominin populations went extinct on account of the Toba super-eruption.

Instead, archaeological evidence indicates that humans survived and coped with one of the largest volcanic events in human history, demonstrating that small bands of hunter-gatherers were adaptable in the face of environmental change. Nevertheless, the peoples who lived around Dhaba more than 74,000 years ago do not seem to have significantly contributed to the gene pool of contemporary peoples, suggesting that these hunter-gatherers likely faced a series of challenges to their long-term survival, including the dramatic environmental changes of the following millennia. In summarizing the wider implications of this study, Professor Michael Petraglia of the Max Planck Institute says, "The archaeological record demonstrates that although humans sometimes show a remarkable level of resilience to challenges, it is also clear that people did not necessarily always prosper over the long term."

A research group, consisting of doctoral student FUJIWARA Ryosuke, Associate Professor TANAKA Tsutomu (both of Kobe University's Graduate School of Engineering) and Research Scientist NODA Shuhei (RIKEN Center for Sustainable Resource Science), has succeeded in improving the yield of target chemical production from biomass. They achieved this through metabolically engineering the bacteria used in bioproduction, so that it would use different kinds of sugar absorbed from the biomass for separate aims.

There are problems encountered when using microbes to produce target chemicals; if the microbes use the carbon sources (sugars) for their own propagation, target chemical production decreases. On the other hand, suppressing this propagation causes the microbes to weaken, resulting in an overall decline in production. To try to solve this issue, the research team developed a new strategy called Parallel Metabolic Pathway Engineering (PMPE), allowing them to control both target chemical production and microbe propagation. They used this approach to alter E. coli bacteria in order to successfully boost the production of the nylon precursor muconic acid.

If it becomes possible to utilize the selected carbon source solely for target chemical production and use the remaining sources for microbe propagation, this will bring about great advances in the production of aromatic compounds and raw materials for medical and chemical products.

The results of this research were first published in Nature Communications on January 14.

Main points

Development of the PMPE strategy which allows the utilization of sugars for microbe propagation and target chemical production to be independently controlled. Using this approach, the research group successfully increased the yield of muconic acid (the target chemical).

PMPE can be applied to the production of various raw materials, such as aromatic compounds and dicarboxylic acid, utilized in chemical products and medicines.

Expected to improve the effective utilization of raw materials, such as biomass, which contain multiple sugars.

Research Background

We rely on fossil fuels as raw materials for producing various products. However, producing petroleum-derived compounds increases the amount of atmospheric CO2, causing a multitude of environmental problems such as global warming.

Consequently, there is a need to develop biorefinery technologies (*1), which involve using microbes to produce chemical compounds from naturally abundant renewable resources such as tree and plant matter. Biomass-derived products have the advantage of being carbon neutral (*2); they do not increase the amount of CO2 in the atmosphere. It is hoped that using biomass to produce various useful compounds can form a basis for a low carbon society, reducing the amount of atmospheric CO2.

Muconic acid is a useful chemical that can be easily converted into adipic acid, an ingredient in nylon production. It is also used as a raw material in the production of various medical and chemical products. However, it is currently chemically synthesized from petroleum resources. It is hoped that a fermentation method could be developed using microbes and renewable plant-based resources with milder reaction conditions and fewer by-products.

However, there are problems with using microbes to produce target chemicals from biomass. There are many cases where even though the microbes utilize the biomass, they propagate themselves instead of producing the target chemical. However, altering the metabolism to prevent the microbes from increasing causes them to weaken, meaning that the target chemicals cannot be synthesized. The balance between microbes' self-propagation and target chemical production is big issue.

To solve this dilemma, the research team developed a new technique called Parallel Metabolic Pathway Engineering (PMPE) in which they separated sugar utilization between microbe propagation and target chemical production, allowing them to control each process independently.

Research Content

Lignocellulosic biomass, which does not compete with global food supplies, is made up of glucose and xylose sugars (Figure 1). The research team developed a metabolic strategy which involved modifying the E. coli bacteria so that it would utilize glucose for target chemical production and xylose for microbe propagation.

In regular microbes, glucose and xylose use the same metabolic pathway and are both utilized for microbe growth and target chemical production (as shown in Figure 2). This reduces the amount of target chemical synthesized because the microbes absorb the sugars to produce and maintain the elements and energy that they require to live.

To mitigate this issue, the research group developed a new strategy called PMPE. As shown in Figure 2, dividing the microbes' metabolic pathway allows each sugar to be utilized independently with all the glucose being used for target chemical production and all the xylose being used for microbe propagation and maintenance. This allowed a greater yield of the target chemical to be produced because none of the glucose was being utilized for microbe growth.

This research group introduced a metabolic pathway to the modified E. coli for synthesizing muconic acid. The modified E. coli utilized the glucose and xylose, leading to the production of the target chemical. The researchers succeeded in producing 4.26 g/L of muconic acid with a yield of 0.31g/g-glucose (Figure 3). This is considered the highest yield in the world, proving the effectiveness of the PMPE strategy.

Subsequently, the researchers investigated whether the PMPE strategy could be applied to the production of target chemicals other than muconic acid. As a result they successfully increased yields of the essential amino acid and aromatic compound phenylalanine, and 1,2- propanediol, which is used as an additive in medicines and food products. These results have shown that PMPE is a versatile technique that can be used to efficiently produce a variety of compounds.

Further Developments

It is expected that the PMPE technique developed by this research group can be applied to increase the production of wide variety of raw materials, such as aromatic compounds and dicarboxylic acid, used in medical and chemical products. Furthermore, this strategy of altering the bacteria's metabolism will allow biomass containing multiple sugars to be more efficiently utilized.

Psychiatrists led by Nikolaos Koutsouleris from Ludwig-Maximilians-Universitaet (LMU) in Munich have used a computer-based approach to assign psychotic patients diagnosed as bipolar or schizophrenic to five different subgroups. The method could lead to better therapies for psychoses.

Diagnostic methods capable of discriminating between the various types of psychoses recognized by psychiatrists remain inadequate. Up to now, doctors have assigned psychotic patients to one of two broad classes - bipolar disorder or schizophrenia - essentially on a symptomatic basis, focusing on shared elements of their psychiatric history, the range of symptoms displayed and the overall pattern of disease progression. This categorization remains a fundamental feature of both clinical practice and psychiatric research, although detailed observations indicate that psychotic illnesses, and the underlying genetic risk factors, are more heterogeneous than the conventional diagnostic dichotomy suggests. Now researchers led by LMU psychiatrist Nikolaos Koutsouleris has carried out a longitudinal cohort study on a sample of 1223 patients over a period of 18 months. The results obtained enabled the team to divide patients into five well defined subgroups, thus providing a more differentiated picture of the pathology of psychoses, which has implications for therapeutic interventions.

Data from 756 of the 1223 patients enrolled in the study were used to establish the new classification scheme, which was then independently validated for the remaining subset of participants. All 1223 patients had been diagnosed with classical psychoses, based on assessment of a total of 188 clinical variables relating to the trajectory of the individual's condition, symptoms, ability to cope with the challenges of everyday life ('functioning'), and cognitive performance. The study set out to determine whether their high-dimensional clinical dataset covering a wide spectrum of psychoses could be decomposed into defined subgroups based on clustering of statistically correlated variables. The data-driven analytical strategy adopted is based on machine learning, which can discover patterns that reveal 'hidden structure' in large collections of multifactorial data. These patterns may in turn point to differences in causal relationships that are of diagnostic relevance. "Our study shows that computer-based analyses can indeed help us to re-evaluate how persons with proven symptoms of psychoses can be differentiated diagnostically," says LMU psychologist Dominic Dwyer, first author of the study, which appears in the journal JAMA Psychiatry.

The analysis ultimately led to the recognition of five clearly defined subgroups among the experimental population. "In addition to differences in their symptomatic and functional course, patients assigned to the different subgroups could also be distinguished on the basis of defined clinical fingerprints," says Nikolaos Koutsouleris, who led the study. Members of one of the subgroups were also differentiated from all the others on the basis of their low scores for educational attainment, which is known to be a potential risk factor for psychotic illness. 

The researchers used a mathematical approach known as non-negative matrix factorization to detect patterns in their statistical data. Using this procedure, they were able to reduce the starting dataset, comprised of 188 variables, to five subgroups defined by core factors. These factors encode hitherto unrecognized relationships between variables and uncover the functional links that connect them. "By evaluating the relative significance of these factors in individual cases, it is possible to assign patients to different groups on the basis of their overall scores," Dwyer explains. In this way, the authors of the study were able to define the following five subgroups of psychoses: affective psychosis, suicidal psychosis, depressive psychosis, high-functioning psychosis and severe psychosis.

"Each of these subgroups can be clearly delimited from all the others on the basis of the clinical data," says Koutsouleris. For instance, patients assigned to Group 5 are characterized by the core factors: schizophrenia diagnosis, significantly lower levels of educational attainment and low verbal intelligence. Most of the patients in this category were males and displayed marked symptoms of psychosis, but no indications of depression or mania. In Group 2, on the other hand, suicidal tendencies were clearly present. The results of the classification of this experimental population which provided the underlying data for the construction of the statistical model were confirmed for an independent group of 458 subjects.

The analyses suggested that unbiased, data-driven clustering may be used to stratify individuals into groups that have different clinical signatures, illness trajectories, and genetic underpinnings. In the future, such computer-assisted categorisations may be integrated into clinical routine through the use of online tools. Koutsouleris and his team have developed a prototype of such an online tool that can be used to stratify new individuals into the same groups and predict outcomes that can be tested at http://www.proniapredictors.eu.

The discovery of a calcium channel that is likely a 'missing link' in the evolution of mammalian calcium channels has been reported today in the open-access journal eLife.

Calcium channels that open and close in response to electrical signals in the brain are essential for thought, memory and muscle contractions. Studying the structure and evolution of these calcium channels in various organisms has revealed a lot about how they work.

"Based on previous studies, scientists have predicted that the calcium channels found in mammals evolved from a bacterial ancestor, but they haven't been able to find this missing link," explains lead author Takushi Shimomura, Assistant Professor in the Division of Biophysics and Neurobiology, National Institute for Physiological Sciences, Japan. "Identifying this ancestor-like bacteria calcium channel is expected to help us understand the structural, functional and evolutionary relationship between bacterial and mammalian calcium channels."

Shimomura and his team scoured the genetic sequences of bacterial voltage-gated calcium channels (CaVs) for potential ancestor-like candidates. They found one candidate called CavMr in the bacterium Meiothermus ruber. CavMr is evolutionarily distinct from other bacterial channels that have been reported.

Next, they studied what happened when they inserted mutations into the gene that encodes CavMr. Their mutational analyses indicated that the small glycine residue in the CavMr selectivity filter is an overlooked feature that determines calcium selectivity. The glycine residue is also well conserved in the selectivity filter of subdomain I and III of mammalian CaVs. These findings led the team to conclude that CavMr links calcium channels to a bacterial ancestor.

"Our work provides new insight on the universal mechanism of calcium selectivity in both mammals and bacteria," says senior author Katsumasa Irie, Assistant Professor at the Cellular and Structural Physiology Institute, Nagoya University, Japan. "CavMr might also be useful for studies that manipulate calcium signalling to learn more about how it controls brain activity."

Irie adds that studying the structural information of these calcium channels could provide a deeper understanding of channel evolution and help explain the origin and principles underlying calcium selectivity.

Resistance to a deadly disease that is affecting the second most farmed fish in the world has been found to be mainly due to differences in genes between families of the same fish.

The breakthrough could help protect stocks of Tilapia fish, which is an important food source in Africa, Asia and South America and worth nearly $10 billion to the global economy.

Since its detection in 2014, Tilapia Lake Virus (TiLV) has ravaged Tilapia populations in 16 countries across three continents.

Clinical signs of the virus observed in tilapia include behavioral changes, discoloration, skin hemorrhages, loss of scales, eyeball protrusion and abdominal swelling. There are currently no treatments or vaccines for TiLV.

Experts believe that selective breeding of fish with the resistance genes may be one way of limiting the damage of this disease, with up to 90 per cent of fish dying once infected.

Researchers from University of Edinburgh's Roslin Institute and WorldFish analysed the genes of 1,821 Genetically Improved Farmed Tilapia (GIFT), which were tagged and placed in a pond that had an outbreak of TiLV.

The fish used in this experiment were members of 124 families, and the team discovered that there was a large variation in family survival. Some family groups had no deaths, whereas others found to have a 100 per cent death rate.

The team then used statistical models to show that resistance to the virus was very heritable, and this means that selective breeding to produce more resistant tilapia strains is likely to be effective.

The variation in TiLV resistance were found to be independent of genetic variation in growth, meaning that any future breeding programmes for GIFT that produce fish resistant to TiLV will not adversely affect the growth of the fish, and will benefit farmers' yields.

The GIFT strain was been selectively bred to be fast growing and adaptable to a wide range of environments. The strain is produced in at least 14 countries, helping to reduce poverty and hunger.

Tilapia is an affordable food source for many people, particularly in developing countries. It is the fourth most consumed fish in the United States.

Fast growing and a healthy source of protein, nutrients and essential fatty acids, Tilapia is easily grown on small or large fish farms.

Professor Ross Houston, lead author and Personal Chair of Aquaculture Genetics at the Roslin Institute, said: "Tilapia Lake Virus poses a real problem to fish famers worldwide, impacting on the livelihoods and food security of millions of people. This research is the result of a long term collaboration between Roslin and WorldFish, and is the first step to breeding tilapia strains with improved resistance to the virus."

This research project was funded with UK aid from the UK government and was undertaken in the framework of the CGIAR Research Program on Fish Agri-Food Systems. The research findings have been published in the journal Aquaculture.

Michael Phillips, Director of CGIAR Research Program on Fish Agri-Food Systems Aquaculture and Fisheries Sciences, WorldFish, said: "This is a truly exciting finding at the frontier of fish genetics. WorldFish will build on this research, with our partners in the research, donor and investment community, to accelerate the further development of resilient TiLV resistant tilapia strains and their wide accessibility to small scale fish farmers."

They say a picture is worth a thousand words. Nowhere is this principle more true than in the world of social media. There, people choose cab drivers, Airbnb rentals and even life partners based on photos.

In online transactions like Airbnb, photos play an outsized role in a renter's decision-making process: Which host looks trustworthy? Who do I think will provide me a nice rental--one that closely resembles the photos they posted?

Professors Eyal Ert and Aliza Fleischer at Hebrew University of Jerusalem's Department of Environmental Economics and Management set out to answer these questions and published their findings in Psychology & Marketing. They analyzed 320 Airbnb listings in Stockholm, Sweden and gleaned two main criteria that determine "visual trustworthiness": One, is the host's characteristics (e.g., gender, facial expression) and the second is the quality of the image itself (e.g., blurry or clear). "Our new study quantified the qualities that define the sort of attractiveness that online shoppers identify with trustworthiness," explained Ert.

While studying hosts' photos, Ert and Fleischer discovered a "trustworthiness" pecking order: women are deemed more trustworthy than men, older hosts over younger ones, smiling faces over neutral expressions, attractive hosts over unattractive ones. As for image characteristics, the pair found that high-quality photographs did better than blurry ones, and photos that showed the host interacting with other people ("a multi-person photo") did better than solo shots of the host. The thinking is that if a host is seen interacting with friends then it may signal their ability to maintain relationships, akin to a stamp of approval for reliability.

"Visual trustworthiness is king in the Airbnb arena. Hosts who are perceived as trustworthy enjoy higher prices and more frequent rentals than do hosts with less-trustworthy photos," added Fleischer. Notably, race was not a factor in their analysis since 98 percent of the Swedish hosts were Caucasian.

Given the primacy of profile pictures in online commerce, it is interesting to note that Airbnb hosts are often unaware of these insights. While most smile in their photos (68%) the researchers would have expected to see more photographs of women, at least in those cases where the property is owned by people of both genders.

Word to the wise, shared Ert and Fleischer, a high-resolution, multi-person shot of an elderly female host who is smiling is more likely to attract Airbnb guests than will photos of young hosts, men or poor-quality shots where the host's face is obstructed.

Using Salmonella enterica genomes recovered from human skeletons as old as 6,500 years, an international team of researchers illustrates the evolution of a human pathogen and provides the first ancient DNA evidence in support of the hypothesis that the cultural transition from foraging to farming facilitated the emergence of human-adapted pathogens that persist until today.

The Neolithic revolution, and the corresponding transition to agricultural and pastoralist lifestyles, represents one of the greatest cultural shifts in human history, and it has long been hypothesized that this might have also provided the opportunity for the emergence of human-adapted diseases. A new study published in Nature Ecology & Evolution led by Felix M. Key, Alexander Herbig, and Johannes Krause of the Max Planck Institute for the Science of Human History studied human remains excavated across Western Eurasia and reconstructed eight ancient Salmonella enterica genomes - all part of a related group within the much larger diversity of modern S. enterica. These results illuminate what was likely a serious health concern in the past and reveal how this bacterial pathogen evolved over a period of 6,500 years.

Searching for ancient pathogens

Most pathogens do not cause any lasting impact on the skeleton, which can make identifying affected archeological remains difficult for scientists. In order to identify past diseases and reconstruct their histories, researchers have turned to genetic techniques. Using a newly developed bacterial screening pipeline called HOPS, Key and colleagues were able to overcome many of the challenges of finding ancient pathogens in metagenomics data.

"With our newly developed methodologies we were able to screen thousands of archaeological samples for traces of Salmonella DNA," says Herbig. The researchers screened 2,739 ancient human remains in total, eventually reconstructing eight Salmonella genomes up to 6,500 years old - the oldest reconstructed bacterial genomes to date. This highlights an inherent difficulty in the field of ancient pathogen research, as hundreds of human samples are often required to recover just a single microbial genome. The genomes in the current study were recovered by taking samples from the teeth of the deceased. The presence of S. enterica in the teeth of these ancient individuals suggests they were suffering from systemic disease at their time of death.

The individuals whose remains were studied came from sites located from Russia to Switzerland, representing different cultural groups, from late hunter-gatherers to nomadic herders to early farmers. "This broad spectrum in time, geography and culture allowed us, for the first time, to apply molecular genetics to link the evolution of a pathogen to the development of a new human lifestyle," explained Herbig.

"Neolithization process" provided opportunities for pathogen evolution

With the introduction of domesticated animals, increased contact with both human and animal excrement, and a dramatic change in mobility, it has long been hypothesized that "Neolithization" - the transition to a sedentary, agricultural lifestyle - enabled more constant and recurrent exposure to pathogens and thus the emergence of new diseases. However, prior to the current study, there was no direct molecular evidence.

"Ancient metagenomics provides an unprecedented window into the past of human diseases," says lead author Felix M. Key, formerly of the Max Planck Institute for the Science of Human History and now at the Massachusetts Institute of Technology. "We now have molecular data to understand the emergence and spread of pathogens thousands of years ago, and it is exciting how we can utilize high-throughput technology to address long standing questions about microbial evolution."

Humans, Pigs, and the Origin of Paratyphi C

The researchers were able to determine that all six Salmonella genomes recovered from herders and farmers are progenitors to a strain that specifically infects humans but is rare today, Paratyphi C. Those ancient Salmonella, however, were probably not yet adapted to humans, and instead infected humans and animals alike, which suggests the cultural practices uniquely associated with the Neolithization process facilitated the emergence of those progenitors and subsequently human-specific disease. It was previously suggested that this strain of Salmonella spread from domesticated pigs to humans around 4000 years ago, but the discovery of progenitor strains in humans more than 5000 years ago suggests they might have spread from humans to pigs. However, the authors argue for a more moderate hypothesis, where both human and pig specific Salmonella evolved independently from unspecific progenitors within the permissive environment of close human-animal contact.

"The fascinating possibilities of ancient DNA allow us to examine infectious microbes in the past, which sometimes puts the spotlight on diseases that today most people don't consider to be a major health concern," says Johannes Krause, director at the Max Planck Institute for the Science of Human History.

The current study allows the scientists to gain a perspective on the changes in the disease over time and in different human cultural contexts. "We're beginning to understand the genetics of host adaptation in Salmonella," says Key, "and we can translate that knowledge into mechanistic understanding about the emergence of human and animal adapted diseases."

The scientists hope that the current study will illuminate the possibilities of these methods and that future research will further examine the ways that human cultural evolution has impacted and driven the evolution of human-adapted diseases.

Young burglars are driven by a desire for excitement when they initially commit crime, new research from the University of Portsmouth has found.

The paper published today highlights the importance of positive emotion in the initial decisions to commit crime which drive the young person into habitual offending.

Researchers compared findings from younger (average age 20) with older, experienced residential burglars (average age 39) after they completed a 'virtual burglary' where participants use a simulated environment to choose and burgle a property. They were asked to 'think aloud' during the re-enactment and then were interviewed by researchers.

Participants were asked about the days and hours before the burglary to try and establish the processes that led them to be involved in the first place.

Dr Claire Nee, Reader in Forensic Psychology, who led the research, said: "It's important to understand under what circumstances young people make that initial decision to commit a crime, so we can think about intervention. The role of emotion in driving the desire to commit crime is a much neglected area and our research indicates it could be key to stopping it in its tracks. The excitement drives the initial spate of offending, but skill and financial reward quickly take over resulting in habitual offending.

"What really struck me about the research is how young offenders can't identify a clear initial decision to commit a burglary - it's just part of the 'flow' of what they're doing with their adolescent comrades."

The research shows that offenders tended to drift into crime rather than any distinct turning point. Offending was often considered an integral and almost inevitable part of participants' lifestyles.

One young burglar said: "Like where I'm from... that's what it's like, it's crime, like, that's the norm." An adult burglar expressed similar sentiments: "I was just born on the streets... that's what people do."

The research discovered a pattern which shows that initiation into burglary is linked originally to the desire for excitement and the 'thrill' of committing the offence, but this thrill reduces once the offender has repeatedly committed a crime.

Having completed one burglary, offenders became motivated by the experience of making quick, easy money. One participant said: "I just had so much money and I was thinking, wow, is this what 10 minutes of work is."

Dr Nee said: "It is fascinating to explore the stages of a criminal's career, so we can see what motivates them at the start, what continues to motivate them, and how we might be able to intervene."

The paper is published in the British Journal of Criminology.

Mantis shrimp (Squilla mantis) don't take kindly to captivity. 'They have a general baseline of being angry', chuckles Kate Feller, currently at the University of Minnesota, USA, recalling how the contrary stomatopods are particularly keen to lash out when exposed to air. 'I had developed a means of holding mantis shrimp with their striking appendages out of water while their gills [arranged beneath the tail] remained submerged for an electrophysiology study I was conducting', recalls Feller. However, when Greg Sutton from the University of Lincoln, UK, wandered past her University of Cambridge (UK) lab bench, he noticed the exposed crustaceans and commented that it would be interesting to measure their hammer blows in air. 'No one had done that', explains Feller. Knowing that the animals launch their ballistic appendages at the speed of a bullet in dense water, it seemed likely that they could even exceed those eye-watering speeds in thinner air. However, when Feller set up Paloma Gonzalez-Bellido's high speed camera to catch the angry animals in the act, she was astonished when she realised that the crustaceans' blows were nowhere near as powerful out of the water as they were in it. They publish their discovery in Journal of Experimental Biology at http://jeb.biologists.org.

'We stimulated them to strike by poking them in the abdomen with a blunt stick. It was like poking them in the tummy, which they hated', she says, adding that the manoeuvre was not without risk. 'I have a pretty epic photo of my bleeding hand over a white sink when one stabbed me during this process', she smiles. And at first glance, the animals' blows looked every bit as punchy as those beneath water. However, when Feller analysed the spring-loaded air-blows, she was puzzled; the manoeuvre was only half as fast: 'The air strikes only averaged about 18 km h?1, which is pretty pitiful even for a slow striker like S. mantis', she says. In fact, when she and Sutton compared the mantis shrimp blows with another spring-loaded manoeuvre - grasshopper leaps - it turned out that the crustaceans were only packing 0.42W of power into their 1.2g hammers, the same as the leaping grasshoppers, even though they are capable of propelling their hammers in water with ten times more power (4W).

Puzzled by the mantis shrimps' lacklustre performance, Feller and Sutton initially wondered if the animals' spring-loaded propulsion mechanism was simply unable to transmit as much power in air as in water. But then, a paper by Sheila Patek's lab was published showing that the crustaceans can fine-tune their blows depending on the context. Feller and Sutton realised that the exposed mantis shrimp were more likely downgrading their blows in the thinner material.

But why were the crustaceans pulling their punches when they could have taken the opportunity to make even more of a mess of Feller's fingers? 'My hypothesis is that this may be related to how mantis shrimp dissipate the excess energy of their strike', she says. Locusts and other leaping insects have energy-absorbing structures at the back of the limb to protect joints from damage, whereas the explosive energy released by submerged mantis shrimps is usually dissipated by their tough opponents and the hard snail shells they target. 'In air, not only are the forces of drag from water absent, but the entire sensory experience is messed up, so maybe - in the absence of a perceived target - the animals don't give it the full pow so they don't blow out their joint', Feller suggests. In other words, the crustaceans' pulled air-punches might simply be a matter of self-preservation.

Everyone approaches romantic relationships differently. On one end of the spectrum are people who crave closeness so much, they may come across as "clingy." On the other end are those who value their independence so deeply that they avoid getting too close to anyone else.

Those two extremes of romantic attachment orientation - known as attachment anxiety and attachment avoidance - can both have negative consequences for well-being due, at least in part, to financial reasons, a study led by the University of Arizona found.

The study, based on data collected from 635 college-educated young adults in romantic relationships, found that people with high attachment anxiety and people with high attachment avoidance both reported low life satisfaction and low relationship satisfaction. Those with attachment anxiety also reported low financial satisfaction.

In addition, the study found that those with high attachment anxiety and those with high attachment avoidance engaged in more irresponsible financial behaviors. They also perceived their partners' financial behaviors as being irresponsible.

"This study suggests that romantic attachment orientation can affect financial behaviors and perceptions of partners' financial behaviors," said University of Arizona researcher Xiaomin Li, lead author of the study, which is published in the Journal of Family and Economic Issues.

It's well-established in the scientific literature that finances play a significant role in well-being. Li's study highlights how attachment orientation can affect well-being via finances.

"People's own less responsible financial behaviors and their perceptions of their romantic partners' less responsible financial behaviors were associated with multiple life outcomes," said Li, a doctoral student in the Norton School of Family and Consumer Sciences in the University of Arizona College of Agriculture and Life Sciences.

Some Try to Buy Love

A person's attachment orientation usually develops in early childhood and persists throughout a person's lifetime for all different types of relationships, including romantic ones, Li said. Attachment anxiety and attachment avoidance are both considered "insecure attachment orientations."

Li and her colleagues found that for study participants with attachment anxiety, the participants' own irresponsible financial behaviors were associated with low financial satisfaction and low life satisfaction. Participants' negative perceptions of their partners' behaviors were also associated with low financial satisfaction and low life satisfaction, as well as low relationship satisfaction.

For participants high in attachment avoidance, their negative perceptions of their partners' financial behaviors - but not their own irresponsible financial behaviors - were associated with low relationship satisfaction.

Li said those with high attachment anxiety and those with high attachment avoidance may engage in irresponsible financial behavior for different reasons.

"People who are high in attachment anxiety may use money to get attention from other people," she explained. For example, they might buy expensive gifts to try to win a partner's love.

On the other hand, those with attachment avoidance - who tend to be more dismissive of others and rely primarily on themselves - may engage in less responsible spending for their own gain.

"Some researchers have found that people with high attachment avoidance place a high value on materialism," Li said. Therefore, they may engage in compulsive buying or make expensive purchases as a way of showing that they are "better than others," she said.

There may also be different explanations for why anxious and avoidant study participants both perceived their partners' behaviors as irresponsible.

Those high in attachment avoidance simply may not value their partner very highly, Li said. On the other hand, those high in attachment anxiety might distrust their partners as the result of their own insecurity in the relationship.

Li hopes future studies will continue to explore how nonfinancial factors, such as attachment orientation, may affect financial behaviors and perceptions and, in turn, well-being.

Li's co-authors on the study were UArizona researchers Melissa Curran and Ashley LeBaron in the Norton School of Family and Consumer Sciences, Joyce Serido at the University of Minnesota and Soyeon Shim at the University of Wisconsin - Madison.