Earth

Plants can't do without phosphorus. But there is often a 'withdrawal limit' on how much phosphorus they can get from the soil. That's because phosphorus in soils is often in forms that plants can't take up. That affects how healthy and productive the plants can be.

One influence on phosphorus availability is the soil's pH level.

If soils are too acidic, phosphorus reacts with iron and aluminum. That makes it unavailable to plants. But if soils are too alkaline, phosphorus reacts with calcium and also becomes inaccessible.

"Phosphorus is most available to plants when soil is at a 'Goldilocks' zone of acidity," says Andrew Margenot. Margenot is a researcher at the University of Illinois at Urbana-Champaign.

There are ways to make more phosphorus available to plants. For example, adding lime (calcium hydroxide) reduces soil acidity. That can unlock the phosphorus that was previously unavailable. This is a common practice. "Liming is a bread-and-butter tool for agriculture," says Margenot.

However, liming can influence other ways by which phosphorus might become available to plants. Enzymes, called phosphatases, are also known to influence the amount of phosphorus available to plants. Margenot's study looked at liming and soil management history to see if it influenced the activity of soil enzymes.

Margenot and his colleagues conducted experiments in western Kenya, a region with acidic, weathered soils.

Researchers added varying amounts of lime to long-term experimental plots. These plots had specific fertilization treatments since 2003: One set of plots had been unfertilized. Another had received cow manure. A third set of plots had mineral nitrogen and phosphorus added.

Twenty-seven days after liming, the researchers measured phosphatase activity. They also measured how much phosphorus was available to plants.

They found no clear relationships between soil acidity levels changed by liming and phosphatase activity.

This was unexpected. "We know that phosphatases are sensitive to soil acidity levels," says Margenot. "Our findings show that it is more complicated than just soil acidity when it comes to these enzymes."

And more surprisingly, changes in phosphatase activities after liming depended on the soil's history. This suggests that the sources of these enzymes (microbes, plant roots) could have responded to different fertilization histories by changing the amount or type of phosphatases secreted.

Furthermore, in all cases, the increases in phosphorus availability were relatively small. "In the soils tested, lime alone was not enough to be meaningful to crops and thus farmers," says Margenot. "Lime needs to be combined with added phosphorus to meet crop needs in these soils."

Margenot is now working to extend this study. With colleagues from the International Center for Tropical Agriculture (CIAT) and the German Society for International Cooperation (GIZ), he'll be studying western Kenyan farms. The goal is to see if using lime at rates realistic for growers will have soil health trade-offs in these weathered soils.

Read more about this research in Soil Science Society of America Journal.

If people cannot adapt to future climate temperatures, deaths caused by severe heatwaves will increase dramatically in tropical and subtropical regions, followed closely by Australia, Europe and the United States, a global new Monash-led study shows.

Published today in PLOS Medicine, it is the first global study to predict future heatwave-related deaths and aims to help decision makers in planning adaptation and mitigation strategies for climate change.

Researchers developed a model to estimate the number of deaths related to heatwaves in 412 communities across 20 countries for the period of 2031 to 2080.

The study projected excess mortality in relation to heatwaves in the future under different scenarios characterised by levels of greenhouse gas emissions, preparedness and adaption strategies and population density across these regions.

Study lead and Monash Associate Professor Yuming Guo said the recent media reports detailing deadly heatwaves around the world highlight the importance of the heatwave study.

"Future heatwaves in particular will be more frequent, more intense and will last much longer," Associate Professor Guo said.

"If we cannot find a way to mitigate the climate change (reduce the heatwave days) and help people adapt to heatwaves, there will be a big increase of heatwave-related deaths in the future, particularly in the poor countries located around the equator."

A key finding of the study shows that under the extreme scenario, there will be a 471 per cent increase in deaths caused by heatwaves in three Australian cities (Brisbane, Sydney and Melbourne) in comparison with the period 1971-2010.

"If the Australia government cannot put effort into reducing the impacts of heatwaves, more people will die because of heatwaves in the future," Associate Professor Guo said.

The study comes as many countries around the world have been affected by severe heatwaves, leaving thousands dead and tens of thousands more suffering from heatstroke-related illnesses. The collective death toll across India, Greece, Japan and Canada continues to rise as the regions swelter through record temperatures, humidity, and wildfires. Associate Professor Antonio Gasparrini, from the London School of Hygiene & Tropical Medicine and study co-author, said since the turn of the century, it's thought heatwaves have been responsible for tens of thousands of deaths, including regions of Europe and Russia.

"Worryingly, research shows that is it highly likely that there will be an increase in their frequency and severity under a changing climate, however, evidence about the impacts on mortality at a global scale is limited," Associate Professor Gasparrini said.

"This research, the largest epidemiological study on the projected impacts of heatwaves under global warming, suggests it could dramatically increase heatwave-related mortality, especially in highly-populated tropical and sub-tropical countries. The good news is that if we mitigate greenhouse gas emissions under scenarios that comply with the Paris Agreement, then the projected impact will be much reduced."

Associate Professor Gasparrini said he hoped the study's projections would support decision makes in planning crucial adaptation and mitigation strategies for climate change.

In order to prevent mass population death due to increasingly severe heatwaves, the study recommends the following six adaption interventions, particularly significant for developing countries and tropical and subtropical regions:

Individual: information provision, adverting

Interpersonal: Information sharing; communication; persuasive arguments; counselling; peer education

Community: Strengthening community infrastructure; encouraging community engagement; developing vulnerable people group; livelihoods; neighbourhood watch

Institutional: Institutional policies; quality standards; formal procedures and regulations; partnership working

Environmental: Urban planning and management; built environment; planting trees; public available drink water; house quality

Public policy: Improvement of health services; poverty reduction; redistribution of resources; education; heatwave-warning system.

In recent years optical fibers have served as sensors to detect changes in temperature, like a thermometer, and pressure, like an artificial nerve. This technique is particularly useful in structures such as bridges and gas pipelines.

EPFL researchers have now come up with a new method that enables optical fibers to identify whether they are in contact with a liquid or a solid. This is achieved by simply generating a sound wave with the help from a light beam within the fiber.

This study was conducted by the Group for Fibre Optics (GFO) run by Luc Thévenaz within the School of Engineering and has been published in Nature Communications.

A sensor that doesn't disturb the light

No wider than a strand of hair, an optical fiber made of glass transmits light that varies according to four parameters: intensity, phase, polarization and wavelength. These parameters are altered when the fiber is stretched or the temperature changes, enabling the fiber to act like a sensor by detecting cracks in structures or abnormal temperatures. But up to now it was not possible to determine what was happening around the fiber without having light escape the fibre, which disrupts its path.

The method developed at EPFL uses a sound wave generated inside the fiber. It is a hyper-frequency wave that regularly bounces off the fiber's walls. This echo varies at different locations depending on the material the wave comes into contact with. The echoes leave an imprint on the light that can be read when the beam exits the fiber, making it possible to map out the fiber's surroundings. This imprint is so faint that it hardly disturbs the light propagating within the fiber. The method could be used to sense what is going on around a fiber and send light-based information at the same time.

The researchers have already immersed their fibers in water and then in alcohol, before leaving them out in the open air. Each time, their system was capable of correctly identifying the change in the surroundings. "Our technique will make it possible to detect water leakages, as well as the density and salinity of fluids that come into contact with the fiber. There are many potential applications," says Thévenaz.

Spatial and temporal detection

These changes in the surroundings are located thanks to a simple time-based method. "Each wave impulse is generated with a slight time lag. And this delay is reflected upon the beam's arrival. If there were any disturbances along the way, we can both see what they were and determine their location," explains Thévenaz. "For the moment, we can locate disturbances to within around ten meters, but we have the technical means to increase our accuracy to one meter."

The idea of using a sound wave in optical fibers initially came from the team's partner researchers at Bar-Ilan University in Israel. Joint research projects should follow.

An artificial-intelligence approach created at the University of North Carolina at Chapel Hill Eshelman School of Pharmacy can teach itself to design new drug molecules from scratch and has the potential to dramatically accelerate the design of new drug candidates.

The system is called Reinforcement Learning for Structural Evolution, known as ReLeaSE, and is an algorithm and computer program that comprises two neural networks which can be thought of as a teacher and a student. The teacher knows the syntax and linguistic rules behind the vocabulary of chemical structures for about 1.7 million known biologically active molecules. By working with the teacher, the student learns over time and becomes better at proposing molecules that are likely to be useful as new medicines.

Alexander Tropsha, Olexandr Isayev and Mariya Popova, all of the UNC Eshelman School of Pharmacy, are the creators of ReLeaSE. The University has applied for a patent for the technology, and the team published a proof-of-concept study in the journal Science Advances last week (DOI: 10.1126/sciadv.aap7885).

"If we compare this process to learning a language, then after the student learns the molecular alphabet and the rules of the language, they can create new 'words,' or molecules," said Tropsha. "If the new molecule is realistic and has the desired effect, the teacher approves. If not, the teacher disapproves, forcing the student to avoid bad molecules and create good ones."

ReLeaSE is a powerful innovation to virtual screening, the computational method widely used by the pharmaceutical industry to identify viable drug candidates. Virtual screening allows scientists to evaluate existing large chemical libraries, but the method only works for known chemicals. ReLeASE has the unique ability to create and evaluate new molecules.

"A scientist using virtual screening is like a customer ordering in a restaurant. What can be ordered is usually limited by the menu," said Isayev. "We want to give scientists a grocery store and a personal chef who can create any dish they want."

The team has used ReLeaSE to generate molecules with properties that they specified, such as desired bioactivity and safety profiles. The team used the ReLeaSE method to design molecules with customized physical properties, such as melting point and solubility in water, and to design new compounds with inhibitory activity against an enzyme that is associated with leukemia.

"The ability of the algorithm to design new, and therefore immediately patentable, chemical entities with specific biological activities and optimal safety profiles should be highly attractive to an industry that is constantly searching for new approaches to shorten the time it takes to bring a new drug candidate to clinical trials," said Tropsha.

Like many chronic infections, visceral leishmaniasis thwarts the immune system's defenses so it can settle comfortably into its host. Responsible for tens of thousands of deaths around the world every year, visceral leishmaniasis holds the unfortunate distinction of being the second leading cause of death by parasitic infection, after malaria. But how does it slip through the host's defenses? Professor Simona Stäger's team at INRS has discovered a mechanism that Leishmania donovani takes advantage of to sustain the infection. It has shown that damage from chronic inflammation induces the death of white blood cells essential to eliminating the parasite. The findings, which were published in the prestigious journal Cell Reports, not only have the potential to lead to possible treatment, they also bring to light a phenomenon that may be shared by other chronic infections.

WEAKENED DEFENSES

At the heart of the immune response, CD4 T cells are essential to controlling an infection. This type of white blood cell participates in the immune response by signaling the presence of a pathogen to be eliminated. To do this, CD4 T cells produce a molecule called interferon gamma (IFN-γ), which activates the cells that destroy pathogens.

In the case of visceral leishmaniasis, CD4 T cells expressing IFN-γ (Th1 cells) appear later than expected during infection and in smaller numbers, a phenomenon that had puzzled researchers. "Now we've found the reason why there are so few," said Professor Stäger. "Unfortunately, these protective cells are dying."

DISCOVERY OF A MECHANISM COMMON TO CHRONIC INFECTIONS

To understand how CD4 T cells are dying, researchers followed a lead identified in one of their recent studies. They had noticed the presence of a transcription factor unusual for these cells. A transcription factor is a protein that modulates the activity of one or more genes. The detected factor, IRF-5, is known for its action in innate immunity cells, but is role was totally unknown in CD4 T cells.

Professor Stäger's new findings show that IRF-5 leads Th1 cells to self-destruct. Tracing the thread of molecular events, the immunologist pinned down the trigger for this unexpected cell death: tissue destruction. Following a series of reactions, which are still not fully understood, the destroyed tissue activates previously unknown signals in Th1 cells, causing them to die.

The white blood cells that orchestrate the attack are thus eliminated--not by the parasite but by a biological process of the host--sustaining the chronic infection and protecting the parasite. In fact, this mechanism may also be at play in other chronic infections that lead to inflammation.

Given the importance of better understanding the workings of this process, INRS professor successfully secured $1 million in funding from the Canadian Institutes of Health Research. The cellular activity induced by IRF-5 in immune cells could reveal as-yet unknown therapeutic targets not only for visceral leishmaniasis, but also for other chronic inflammatory diseases.

DETAILS OF THE SIGNALING MECHANISM

The study presented by Professor Simona Stäger's team points to a mechanism involving the TLR7 receptor (Toll-like Receptor 7), usually activated in innate immune system cells by pathogen recognition. In the case of chronic inflammation, the cellular residues present after tissue destruction activate TLR7 in Th1 cells. Activation of TLR7 induces expression and activation of IRF-5, which in turn increases expression of DR5 (Death Receptor 5) and caspase 8, two signaling elements leading to cell death. Thus, chronic inflammation induces the death of protective CD4 T cells via the TLR7-IRF-5 cellular pathway.

Vermont recently moved to extend the jurisdiction of its juvenile courts from age 18 to 20, and three other U.S. states (Connecticut, Illinois, and Massachusetts) are considering similar proposals. This comes amid growing awareness that 18- to 25-year-olds are a developmentally distinct group that should be treated differently by the justice system. New research examined juvenile justice in Europe, where most countries have special laws or procedures for this age group; the findings can inform U.S. policymakers.

The study, by researchers at the Harvard Kennedy School and Columbia University, appears in Justice Evaluation Journal, a publication of the Academy of Criminal Justice Sciences.

"Europe has a long history of special practices and laws for young adults, so we looked at Germany, the Netherlands, and Croatia to determine what lessons might be learned in terms of providing more developmentally appropriate responses to youth," explains Sibella Matthews, an Australian attorney and recent graduate at the Harvard Kennedy School, who coauthored the study. "While these three countries have their own distinct approaches to youth justice, they also share similarities worth examining as U.S. policymakers reform their approach to emerging adults."

The researchers found that Germany, the Netherlands, and Croatia all apply juvenile sanctions, facilities, and in some cases, courts, to youth ages 18 or older. The Netherlands and Croatia rely on judicial discretion, meaning that they allow judges to decide whether to apply juvenile or adult sanctions. In Germany, all cases involving youth under age 21 are handled in youth court, and although judicial discretion is applied, most cases result in juvenile sanctions, especially those involving more serious offenses.

The three European countries also tend to divert more juveniles and young adults from formal court processing and prosecution, have higher minimum ages at which juvenile laws can be applied to children, and rely more on educational or rehabilitative approaches to youth involved in delinquent or criminal behavior, the study notes. These countries also tend to have greater confidentiality protections for youth and young adults, and rely less on incarcerating youth in adult or juvenile facilities as a sanction for criminal behavior.

"Justice for young adults is a relatively new field, but interest has been growing quickly in the last few years," says Vincent Schiraldi, a senior research scientist at the Columbia School of Social Work and co-director of Columbia University's Justice Lab, who coauthored the study.

"It is appropriate for the United States to seriously consider adopting the strategies we found in these European countries to serve adolescents and young adults in a manner that is developmentally appropriate."

Adopting these approaches could also help avoid the harm that can be caused by prosecuting very young children and missing the opportunity to serve older adolescents, the authors note. Furthermore, young adults are over-represented in the U.S. justice system and have the highest rates of recidivism, so reforms could improve outcomes for youth as well as public safety.

Mice with pancreatic cancer that were treated with a naturally occurring constituent of medicinal cannabis alongside chemotherapy, survived almost three times longer than those treated with chemotherapy alone, a new study reports.

The study is published in the journal Oncogene and was led by Queen Mary University of London and Curtin University, Australia. It tested the impact of the cannabinoid Cannabidiol (CBD) on the use of the commonly used chemotherapy medication Gemcitabine as a treatment for pancreatic cancer in mice.

Each year around 9,800 people in the UK are diagnosed with pancreatic cancer. The disease is particularly aggressive and has one of the lowest survival rate of all cancers.

Lead researcher Professor Marco Falasca from Queen Mary University of London said: "This is a remarkable result. We found that mice with pancreatic cancer survived nearly three times longer if a constituent of medicinal cannabis was added to their chemotherapy treatment.

"Cannabidiol is already approved for use in clinics, which means we can quickly go on to test this in human clinical trials. If we can reproduce these effects in humans, cannabidiol could be in use in cancer clinics almost immediately, compared to having to wait for authorities to approve a new drug.

"The life expectancy for pancreatic cancer patients has barely changed in the last 40 years because there are very few, and mostly only palliative care, treatments available. Given the five-year survival rate for people with pancreatic cancer is less than seven per cent, the discovery of new treatments and therapeutic strategies is urgently needed."

The cannabinoid CBD does not cause psychoactive effects, as opposed to tetrahydrocannabinol (THC) - the cannabinoid known to cause the psychoactive effects in cannabis. As such, CBD is already cleared for use in the clinic, and does not face the same challenges as products including cannabis oil, which contain controlled substances such as THC.

The researchers add that CBD is also known to improve the side effects of chemotherapy, including nausea, diarrhoea, vomiting, meaning it could also improve the quality of life of patients undergoing chemotherapy.

The research was supported by the UK charity Pancreatic Cancer Research Fund and the Avner Pancreatic Cancer Foundation and also involved researchers from The Beatson Institute for Cancer Research in Scotland.

The study only looked at the effect of this treatment in mice, and clinical trials in humans are needed to confirm whether or not CBD improves survival rates of pancreatic cancer patients.

There may be more habitable planets in the universe than we previously thought, according to Penn State geoscientists, who suggest that plate tectonics -- long assumed to be a requirement for suitable conditions for life -- are in fact not necessary.

When searching for habitable planets or life on other planets, scientists look for biosignatures of atmospheric carbon dioxide. On Earth, atmospheric carbon dioxide increases surface heat through the greenhouse effect. Carbon also cycles to the subsurface and back to the atmosphere through natural processes.

"Volcanism releases gases into the atmosphere, and then through weathering, carbon dioxide is pulled from the atmosphere and sequestered into surface rocks and sediment," said Bradford Foley, assistant professor of geosciences. "Balancing those two processes keeps carbon dioxide at a certain level in the atmosphere, which is really important for whether the climate stays temperate and suitable for life."

Most of Earth's volcanoes are found at the border of tectonic plates, which is one reason scientists believed they were necessary for life. Subduction, in which one plate is pushed deeper into the subsurface by a colliding plate, can also aid in carbon cycling by pushing carbon into the mantle.

Planets without tectonic plates are known as stagnant lid planets. On these planets, the crust is one giant, spherical plate floating on mantle, rather than separate pieces. These are thought to be more widespread than planets with plate tectonics. In fact, Earth is the only planet with confirmed tectonic plates.

Foley and Andrew Smye, assistant professor of geosciences, created a computer model of the lifecycle of a planet. They looked at how much heat its climate could retain based on its initial heat budget, or the amount of heat and heat-producing elements present when a planet forms. Some elements produce heat when they decay. On Earth, decaying uranium produces thorium and heat, and decaying thorium produces potassium and heat.

After running hundreds of simulations to vary a planet's size and chemical composition, the researchers found that stagnant lid planets can sustain conditions for liquid water for billions of years. At the highest extreme, they could sustain life for up to 4 billion years, roughly Earth's life span to date.

"You still have volcanism on stagnant lid planets, but it's much shorter lived than on planets with plate tectonics because there isn't as much cycling," said Smye. "Volcanoes result in a succession of lava flows, which are buried like layers of a cake over time. Rocks and sediment heat up more the deeper they are buried."

The researchers found that at high enough heat and pressure, carbon dioxide gas can escape from rocks and make its way to the surface, a process known as degassing. On Earth, Smye said, the same process occurs with water in subduction fault zones.

This degassing process increases based on what types and quantities of heat-producing elements are present in a planet up to a certain point, said Foley.

"There's a sweet spot range where a planet is releasing enough carbon dioxide to keep the planet from freezing over, but not so much that the weathering can't pull carbon dioxide out of the atmosphere and keep the climate temperate," he said.

According to the researchers' model, the presence and amount of heat-producing elements were far better indicators for a planet's potential to sustain life.

"One interesting take-home point of this study is that the initial composition or size of a planet is important in setting the trajectory for habitability," said Smye. "The future fate of a planet is set from the outset of its birth."

The researchers published their findings in the current issue of Astrobiology.

Note to media: We have not included specific methods of suicide in the press release and ask that journalists avoid listing them to prevent the kind of contagion found in the study.

A large study examining media reporting of suicide found significant associations between reporting details and suicide deaths, underscoring the need for responsible reporting. The study, conducted by an international research team, is published in CMAJ (Canadian Medical Association Journal).

"It is important for reporters and media outlets to understand that how they report on suicide can have a real impact across the population," says Dr. Mark Sinyor, a psychiatrist at Sunnybrook Health Sciences Centre and the University of Toronto, Toronto, Ontario.

The study supports previous research that has shown that exposure to media reporting on suicide may lead some vulnerable people to similar behaviour, a phenomenon called suicide contagion, and in some circumstances, may also lead to help-seeking behaviour.

"When media reports include resources such as crisis services and messages of hope, it can have a positive impact on the public, and potentially help a person in crisis by reminding them that suicide isn't the only option and that help is available," says Dr. Sinyor.

There is limited evidence for which specific characteristics of media reports influence these behaviours, and there is little Canadian research on the topic. However, there are guidelines to help media outlets with best practices in reporting on suicide.

Researchers from Canada, Austria and Australia examined the relationship between potentially harmful and helpful elements of print and online media reports about suicide. They looked at almost 17,000 articles in 13 major publications (including The New York Times) in the Toronto media market and suicide deaths in Toronto from 2011 to 2014. Specifically, the study looked for a link between certain types of reporting and suicide deaths within the 7 days after publication.

The research team identified associations between several specific elements of media reports and suicide deaths. It suggests that reporting on suicide can have a meaningful impact on suicide deaths and that journalists and media outlets/organizations should carefully consider the specific content of reports before publication.

"This study emphasizes the importance of responsible reporting and identifies that relatively few media reports included helpful information such as crisis resources and messages of hope," says Dr. Sinyor.

From 2011 to 2014, there were 6,367 articles with suicide as the major focus and 947 suicide deaths in Toronto over the same period. Several elements were associated with increased suicides, such as describing the method -- especially in the headline -- describing suicide as inevitable and reporting on suicide in celebrities.
Articles about murder-suicides were associated with decreased suicides.

"Contagion is thought to occur when a vulnerable reader identifies with suicide-related media," Dr. Sinyor says. "The fact that reports about celebrity suicide appeared to lead to contagion but the reverse was seen for reports about murder-suicide is very much in keeping with what we know."

"Suicide is a complex phenomenon that is influenced by many factors. We encourage journalists to take extra care to contextualize their reporting, especially when a story is about someone or a situation that people are likely to identify with," says Dr. Sinyor.

"The overwhelming majority of people who think about suicide ultimately find paths to resilience, and they don't die by suicide," he says. "Suicide is almost always accompanied by treatable mental disorders along with life stress and difficulties coping. We have treatments for each of these problems. There is hope. We continue to work with the media in Canada, who do want to get this right, to help them be aware of the issues so that they can inform the public in a way that is safe."

In a related commentary, Dr. Ian Colman, a professor at the School of Epidemiology and Public Health, University of Ottawa, Ottawa, Ontario, writes "Journalists have a key role to play in public discourse on current issues facing society. It is very encouraging that discussions about mental health and suicide have become prominent in recent years, and that the stigma attached to mental health is dropping. The media has likely played an important role in this."

However, he expresses dismay that the study found few media reports that used recommended practices to prevent suicide. "Fewer than one in five articles discussed alternatives to suicide, and less than 2% mentioned community resources for those considering suicide."

"The media have an obligation to report the news, but also have the potential to influence positive change. Responsible reporting can encourage conversations about suicidality, stimulate help-seeking behaviour among individuals considering suicide, and make important contributions in the fight against mental health stigma," he concludes.

The study was conducted by researchers from Sunnybrook Health Sciences Centre and the University of Toronto, Toronto, Ontario; University of Manitoba, Winnipeg, Manitoba; Medical University of Vienna, Vienna, Austria; Melbourne School of Population and Global Health and University of Melbourne, Melbourne, Australia with support from the American Foundation for Suicide Prevention.

"The association between suicide deaths and putatively harmful and protective factors in media reports" is published July 30, 2018.

Higher education institutions in the United States should change their faculty codes of conduct to define bullying as a distinctive form of harassment, according to a new paper published in the National Communication Association's journal First Amendment Studies. Such codes also need to provide faculty and staff with clearer communications regarding bullying, and offer guidance for both targets and bystanders.

Murray State University scholars Frances Smith and Crystal Rae Coel analyzed 276 faculty codes of conduct from a variety of universities and colleges across the United States, and found that only 8 contained specific references to bullying.

Most of the codes mentioned their organization's aversion to harassment - particularly on the basis of race, religion, sex or other factors prohibited by law - but failed to reflect the fact that bullying and harassment are not the same, and that bullying is not restricted to people in legally-protected categories.

The codes also placed emphasis on 'employee engagement', whereby staff were encouraged to create a positive, collegial atmosphere. However, any specific instruction to refrain from bullying or acting as bystanders in bullying situations was missing.

If codes lack a policy delineating intolerance toward workplace bullying and fail to make a clear distinction between harassment and bullying, victims have little recourse once offensive language or behavior is deemed non-discriminatory and not within constitutional protections, the authors note.

An argument can be made that suppressing bullying speech may violate the First Amendment, so effective policies against bullying must also balance First Amendment rights to free expression with the right of all employees to be free from a hostile work environment.

The authors show that policies against workplace bullying can be crafted that are consistent with existing case law governing the scope of public employees' rights to free expression in the workplace. For example, the Supreme Court has ruled that First Amendment protections are available for workplace speech of public employees if it covers matters of public concern without disrupting office operations.

"Through this research, we hope to add to the conversation about workplace bullying. Policies can be incorporated into Faculty Codes of Conduct to provide resources for targets and bystanders without compromising First Amendment rights. We hope to encourage positive steps in reducing bullying within higher education institutions."

The faculty codes of conduct examined in this study do not adequately indicate what bullying behavior is, what to do if you are a target or bystander, or how the organization chooses to proceed when offenses have been made, the authors conclude. They suggest that codes be amended to explicitly cover workplace bullying, and to provide clear guarantees of non-retaliation for employees who file complaints.

Scientists at the U.S. Department of Energy's Ames Laboratory have discovered an earlier unknown discontinuous magnetoelastic transition in a rare-earth intermetallic. The mechanism of the material's changing magnetic state is so unusual, it provides new possibilities for discovery of similar materials.

Materials that possess magnetoelastic phase transitions are highly sought after for a number of developing technologies, including caloric heating and cooling systems. Materials that display this property are rare, and are thought to be exclusively transition metal-based.

But the Ames Laboratory research group found that a rare earth compound made of Europium and Indium, Eu2In, displayed a startlingly sharp magnetic phase transition accompanied with a giant magnetocaloric effect (change in temperature) and no hysteresis.

"This was a very surprising result and one of the least expected places to find such a phenomenon," said Yaroslav Mudryk, an Ames Laboratory scientist. "So this represents the first example of what potentially may become a new class of materials."

"The magnetic phase transition can be explained by an unusual exchange of electrons between the two elements in the compound, with Indium electronic states overlapping with those of Europium," said Durga Paudyal, an Ames Laboratory scientist.

"Now that we have seen this mechanism and are able to explain how it works, we can use this knowledge to look for similar but better materials, one that can be used in future applications like magnetic refrigeration," said Vitalij Pecharsky, Ames Laboratory scientist and Distinguished Professor of Materials Science and Engineering at Iowa State University.

The research is further discussed in the paper, "Non-hysteretic first-order phase transition with large latent heat and giant low-field magnetocaloric effect," authored by F. Guillou, A.K. Pathak, D. Paudyal, Y. Mudryk, F. Wilhelm, A. Rogalev, and V.K. Pecharsky; and published in Nature Communications.

X-ray absorption and magnetic circular dichroism experiments were carried out at the ID12 beamline of the European Synchrotron Radiation Facility, ESRF, France.

Alexandria, Va., USA - At the 96th General Session of the International Association for Dental Research (IADR), held in conjunction with the IADR Pan European Regional (PER) Congress, Yao Liu, China Medical University, Taiwan, Province of China gave an oral presentation titled "PD-1 is Required to Dental Pulp Stem Cell Properties." The IADR/PER General Session & Exhibition is in London, England at the ExCeL London Convention Center from July 25-28, 2018.

Programmed cell death-1 (PD-1) belongs to an inhibitory signaling pathway capable of maintaining immune tolerance. Blockage of PD-1 has been identified as a promising immunotherapeutic approach for cancer and infectious diseases. However, it is unknown whether PD-1 pathway regulates stem cell function. In this study, Liu and co-authors identify a previously unknown role of PD-1 in maintaining stem cell function.

The PD-1 expression in Dental Mesenchymal Stem Cells from dental pulp of Deciduous Teeth (MSC-DT) and Dental Mesenchymal Stem Cells (MSC) from bone marrow (BMMSCs) were analyzed. The results showed that MSC-DT, but not BMMSCs, expressed PD-1. When the PD-1 expression in MSC-DT was removed, the MSC-DT resulted in significantly reduced proliferation rate.

This study indicates that PD-1 is a key surface molecule controlling self-renewal and multipotential differentiation of MSC-DT and identified a previously unknown role of PD-1 in maintaining stem cell function. PD-1 can be used as a unique surface marker to isolate and characterize MSC-DT. This allows researchers to significantly improve the quality and quantity of culture-expanded MSC-DT for potential clinical therapies.

This research was presented as part of the Stem Cell and Tissue Regeneration oral session that took place on Thursday, July 25 from 1:30 p.m. - 3 p.m. at the ExCeL London Convention Center in London, England.

Alexandria, Va., USA - At the 96th General Session of the International Association for Dental Research (IADR), held in conjunction with the IADR Pan European Regional (PER) Congress, John Bartlett, The Ohio State University, Columbus, USA, gave an oral presentation titled "MMP20 May Initiate Enamel Formation via Basement Membrane Degradation." The IADR/PER General Session & Exhibition is in London, England at the ExCeL London Convention Center from July 25-28, 2018.

Matrix metalloproteinase-20 (MMP-20) is an enzyme that in humans is encoded by the MMP20 gene. MMP20 expression is restricted to teeth and its malfunction causes amelogenesis imperfecta, a disorder of tooth development that causes teeth to be unusually small, discolored, pitted or grooved and prone to rapid wear and breakage. In this study, Bartlett and co-authors research whether MMP20 is capable of cleaving basement membrane proteins and if its temporal expression pattern is consistent with degradation of the basement membrane.

While previous studies have demonstrated that MMP20 cleaves type IV collagen, laminin-111 and laminin-332, this study showed that MMP20 also cleaves perlecan (HSPG2). Next, Bartlett performed in situ hybridization to identify when and where MMP20 is expressed along the continuously erupting incisor.

The results showed that MMP20 expression was restricted to ameloblasts of the enamel organ and odontoblast of the pulp organ, and discovered that MMP20 is expressed prior to basement membrane degradation. The basement membrane persisted in mice that had their tissue lining destroyed, but was degraded prematurely in MMP20 overexpressing mice. Thus, MMP20 likely initiates enamel formation beginning with degradation of the basement membrane.

This research was presented as part of the Mineralized Tissue oral session that took place on Wednesday, July 25 from 3:15 p.m. - 4:45 p.m. at the ExCeL London Convention Center in London, England.

'Traffic jams' can also occur in the brain and they can be damaging. Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have been able to confirm that this is the case. They have been able to prove that disrupted transportation routes in nerve cells are a significant cause of Parkinson's disease.

Nerve fibres give nerve cells their characteristic long shape. Measuring up to one metre in length, they form the contact points to other nerve cells. In order to carry out the important task of communicating with other nerve cells, the fine branches of these nerve fibres and their ends, called synapses, must be regularly supplied with energy from the cell body. If this energy supply is interrupted, the synapses are destroyed. Connections between nerve cells are then disrupted, which can lead to the cells dying off. This process is typical for the development of brain disorders such as Parkinson's disease.

It is unclear which mechanisms are responsible for the loss of nerve cells in Parkinson's. Researchers at FAU led by Dr. Iryna Prots and Prof. Dr. Beate Winner from the Department of Stem Cell Biology in conjunction with researchers from the Department of Molecular Neurology (Janina Grosch, head: Prof. Dr. Jürgen Winkler) have now succeeded in demonstrating that a type of 'traffic jam' in the nerve cells could be the cause.

The researchers discovered that the traffic jam is triggered by a protein called alpha-synuclein, which is also found in healthy nerve cells. In abnormal nerve cells, the protein forms deposits, or even lumps, leading to a delay, disrupting the energy supply of the nerve fibres and, ultimately, damaging the synapses.

The researchers were also able to demonstrate this mechanism in cell cultures taken from patients with Parkinson's. A small skin sample was taken from affected patients. These skin cells were then converted into stem cells, which can be developed into any type of cell, and in this case, into nerve cells.

In initial trials, the researchers succeeded in suppressing the formation of lumps of alpha-synuclein, thus improving the transportation of information in the nerve fibres. However, the substance they used has not yet passed clinical trials. Nevertheless, the lead author of the study, Dr. Iryna Prots, says 'Our findings mean we can improve our understanding of the mechanisms that cause Parkinson's and push forward new strategies for treatment during the progression of the disease.'

Two years after a CIRES and CU Boulder team discovered a previously unknown class of waves rippling continuously through the upper Antarctic atmosphere, they've uncovered tantalizing clues to the waves' origins. The interdisciplinary science team's work to understand the formation of "persistent gravity waves" promises to help researchers better understand connections between the layers of Earth's atmosphere--helping form a more complete understanding of air circulation around the world.

"A big picture of Antarctic gravity waves from the surface all the way to the thermosphere is emerging from the studies, which may help advance global atmospheric models," said CIRES Fellow and CU Boulder Professor of Aerospace Engineering Sciences Xinzhao Chu, lead author of the new study published today in the Journal of Geophysical Research - Atmospheres.

"The new understanding results from a series of journal publications, based on multiple years of lidar observations, many made by winter-over students, from Arrival Heights near McMurdo Station in Antarctica."

In the 2016 paper, Chu and her colleagues discovered persistent gravity waves: huge ripples that sweep through the upper atmosphere in 3- to 10-hour periods. And now, by combining observations, theory, and models, they propose two possible origins of those waves: they are either from lower-level waves breaking and re-exciting new waves higher in the sky, and/or from polar vortex winds.

Since 2016, the team managed to track the origin of the upper atmospheric waves down to the lower-altitude stratosphere. The team then characterized the dominant gravity waves there, but found they had very different properties than the persistent waves in the upper atmosphere.

"The upper-atmosphere waves are huge, with a horizontal length of around 1,200 miles (2,000 km), and the lower, stratospheric waves are much smaller--only 250 miles (400 km)," said Jian Zhao, a Ph.D. candidate in CU Aerospace, working in Chu's group, who stayed the 2015 winter over at McMurdo for lidar observations.

Zhao and colleagues previously described the stratospheric waves in an earlier study, and he is second author on the new study which describes how the wave energy varies over seasons and years--documenting those kinds of variations is critical for researchers trying to understand how the waves influence things like global air circulation and climate change.

The team suspects that when these lower, smaller-scale stratospheric gravity waves break, they trigger the formation of the huge waves that then travel to the upper atmosphere through a process called "secondary wave generation."

Evidence from lidar data at McMurdo station pointing to this process was described in a paper published this year, led by Sharon Vadas, a researcher from Northwest Research Associates, and colleagues.

"It's similar to ocean waves breaking on a beach," said Vadas. "When the wind flows downslope from the mountains near McMurdo, the excited mountain waves travel upward in the atmosphere, growing larger and larger until they break over huge scales, creating these secondary gravity waves."

Understanding the origins of the waves relied on Vadas' theory of secondary gravity waves and a global, high-resolution model created by Erich Becker at the Leibniz Institute of Physics in Germany. Becker's model perfectly stitches together the theory and lidar observations. It suggests that secondary wave formation is particularly persistent during winter, and that it occurs not only at McMurdo Station, but at mid to high latitudes in both hemispheres.

Another possible source of the persistent waves is the polar vortex--a persistent pattern of wind and weather that rotates around the South Pole during winter, Chu and her colleagues reported in the latest paper.

"The fast vortex winds could either modify the waves as they move upward, or the winds could actually generate waves themselves," said Lynn Harvey, a coauthor on the study, and researcher at the Laboratory for Atmospheric and Space Physics (LASP) at CU Boulder. "With more observations, we should be able to determine which scenario is true."

Chu and her research colleagues sometimes find themselves sitting at desks running computer models and calculations, and sometimes they are bundled head-to-toe, walking through strong winds and frigid temperatures well-below zero degrees F in Antarctica to run cutting edge lidar systems installed there.

The National Science Foundation-managed U.S. Antarctic Program and the Antarctica New Zealand program have supported the team's work in Antarctica for eight years, starting with the installation of Chu's custom-built lidar systems, which allows her team to probe the most difficult-to-observe regions of the atmosphere. Studying atmospheric waves near the South Pole is critical to improving climate and weather models, and forming a better picture of global atmospheric behavior.

"We still have many unanswered questions," said Chu. "But in about five years, using a combination of observations and high-resolution modelling, we hope to resolve these mysteries."

Two of her students--recent graduate Ian P. Geraghty and Ph.D. student Zimu Li--will travel to Antarctica this October to continue the research.