Tech

Geothermal manifestations at Earth's surface can be mapped and characterized by a variety of well-established exploration methods. However, mapping hydrothermal vents in aquatic environments is more challenging as conventional methods can no longer be applied. In fact, chemical composition of lake water may indicate inflow of fluids from a volcanic system, but it does not provide spatial information on the location of hydrothermal vents, their abundance and current state of activity.

Changes in the behaviour of hydrothermal vents may be indicative of changes in the volcanic system underneath, thus being a useful precursor for the next generation of early warning systems. Increased volcanic activity beneath volcanic lakes could also trigger increased gas input, in particular CO2, which could again result in catastrophic gas outbursts as reported from Lake Nyos or Lake Monoun in Cameroon. New exploration approaches will help improving site-specific risk assessment and monitoring concepts by taking a closer look at hydrothermal vents.

The study describes an integrated approach of (1) bathymetry, (2) thermal mapping of the lake floor, and (3) gas emission measurements at the water surface, which was tested successfully at Lake Ngozi in Tanzania. Multiple hydrothermal feed zones could be identified by hole-like structures and increased lake floor temperatures, in combination with increased CO2 emissions from the lake surface. The developed approach has the advantage that (1) it does not require a complex technical setup, (2) data can be obtained in-situ, and (3) it is transferable to other volcanic lakes for mapping hydrothermal feed sources.

Further research activities at volcanic lakes and in shallow marine environments with hydrothermal activity (e.g., Iceland, Italy) are currently in preparation with partners from the Scientific Diving Centre (SDC) at the Technical University Bergakademie Freiberg, Germany, and the Marine & Freshwater Research Institute in Reykjavík, Iceland. This will also include research related to future offshore geothermal exploration.

When two neutron stars collide, the matter at their core enters extreme states. An international research team has now studied the properties of matter compressed in such collisions. The HADES long-term experiment, involving more than 110 scientists, has been investigating forms of cosmic matter since 1994. With the investigation of electromagnetic radiation arising when stars collide, the team has now focused attention on the hot, dense interaction zone between two merging neutron stars.

Simulation of electromagnetic radiation

Collisions between stars cannot be directly observed - not least of all because of their extreme rarity. According to estimates, none has ever happened in our galaxy, the Milky Way. The densities and temperatures in merging processes of neutron stars are similar to those occurring in heavy ion collisions, however. This enabled the HADES team to simulate the conditions in merging stars at the microscopic level in the heavy ion accelerator at the Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt.

As in a neutron star collision, when two heavy ions are slammed together at close to the speed of light, electromagnetic radiation is produced. It takes the form of virtual photons that turn back into real particles after a very short time. However, the virtual photons occur very rarely in experiments using heavy ions. "We had to record and analyze about 3 billion collisions to finally reconstruct 20,000 measurable virtual photons," says Dr. Jürgen Friese, the former spokesman of the HADES collaboration and researcher at Laura Fabbietti's Professorship on Dense and Strange Hadronic Matter at TUM.

Photon camera shows collision zone

To detect the rare and transient virtual photons, researchers at TUM developed a special 1.5 square meter digital camera. This instrument records the Cherenkov effect: the name given to certain light patterns generated by decay products of the virtual photons. "Unfortunately the light emitted by the virtual photons is extremely weak. So the trick in our experiment was to find the light patterns," says Friese. "They could never be seen with the naked eye. We therefore developed a pattern recognition technique in which a 30,000 pixel photo is rastered in a few microseconds using electronic masks. That method is complemented with neural networks and artificial intelligence."

Observing the material properties in the laboratory

The reconstruction of thermal radiation from compressed matter is a milestone in the understanding of cosmic forms of matter. It enabled the scientists to place the temperature of the new system resulting from the merger of stars at 800 billion degrees celsius. As a result, the HADES team was able to show that the merging processes under consideration are in fact the cosmic kitchens for the fusion of heavy nucleii.

ROCHESTER, Minn. -- Parents, siblings and children of people with celiac disease are at high risk of also having the disease, according to a Mayo Clinic study. This study calls for screening of all first-degree relatives of patients -- not just those who show symptoms.

The retrospective study, to be published in Mayo Clinic Proceedings in September, found that 44% of screened first-degree relatives had celiac disease. Of those patients, 94% had symptoms that were not classic or had no symptoms at all.

"Research has shown that family members of celiac disease patients are at higher risk, and we used our Mayo Clinic data to show that proactive screening of first-degree relatives, regardless of whether they showed symptoms, resulted in diagnoses that would have been missed," says Imad Absah, M.D., a Mayo Clinic pediatric gastroenterologist and the study's lead author.

Celiac disease is an immune reaction to eating gluten, a protein found in wheat, rye and barley, that can damage the lining of the small intestine over time. This can lead to malabsorption of nutrients, and cause diarrhea, fatigue, weight loss and other complications. There's no cure for celiac disease, but patients can manage symptoms with a strict gluten-free diet.

The study looked at a retrospective sample of 104 patients diagnosed with celiac disease between 1983 and 2017, based on Mayo Clinic records and celiac disease registry data. Researchers then identified 477 first-degree relatives, of whom 360 were screened for celiac disease. Of those, 160 were diagnosed with celiac disease. The median period between diagnosis of the initial patient and the relative was just under six months.

More screening for celiac disease among family members could prevent long-term complications, such as nutritional deficiencies, development of new autoimmune conditions, and small bowel malignancy, according to the Mayo Clinic study. Other studies also have shown higher prevalence of celiac disease in family members.

"Gastroenterologists and general practitioners should ask about any family history of celiac disease among their patients' parents, siblings and children. And if they're present during the clinic visit, they should offer screening," says Dr. Absah.

Regarding screening, Joseph Murray, M.D., a Mayo Clinic gastroenterologist and co-author, says that patients should not change their diet to avoid foods containing gluten before testing.

"This research illustrates why it is important for clinicians and patients to be vigilant for celiac disease, especially in those with a family history," Dr. Murray says.

ROCHESTER, Minn. -- Cannabidiol (CBD) oils and products have become increasingly popular with consumers as ways to find relief from aches and pains, anxiety, sleep disturbances and other chronic issues. But are these products safe, and are they helpful?

A review of the latest research, to be published in September in Mayo Clinic Proceedings, finds there's a growing body of preclinical and clinical evidence to suggest that CBD oils may hold promise for treating conditions such as chronic pain and opioid addiction. But few clinical studies on the safety and efficacy of CBD have been reported, and more research involving humans is needed before health care providers can say definitely that they're helpful and safe, according to Mayo Clinic researchers.

"There are many intriguing findings in pre-clinical studies that suggest CBD and hemp oil have anti-inflammatory effects and may be helpful with improving sleep and anxiety," says Brent Bauer, M.D., an internist and director of research for the Mayo Clinic Integrative Medicine program. "But trials in humans are still limited, so it is too early to be definitive about efficacy and safety."

Dr. Bauer says there's reason for concern about a growing number of reports of liver injury in patients who have used CBD products. With greatly increasing patient interest in CBD and hemp oil products, it's important that clinical research moves ahead to better understand their potential value and safety, he says.

"Careful selection of a health care product is crucial, and though these products do not have Food and Drug Administration approval for therapeutic use, patients continue to ask for them and use them. Physicians need to become better informed about these products, and it's important that human trials examine issues of efficacy and safety."

The legalization of marijuana for medicinal purposes has spurred intense interest by consumers in over-the-counter products containing CBD and hemp oil, especially for chronic pain relief. The review in Mayo Clinic Proceedings summarizes the latest research, as well as the current legal status of CBD and hemp oils, and concludes that the products are potentially useful for chronic pain and addiction management. The study's lead author is Harrison J. VanDolah, athird-year medical student at Creighton University School of Medicine.

With CBD a hot consumer trend, physicians may find it easy to dismiss them as unproven and untested. Dr. Bauer encourages health care professionals to learn as much as possible and develop an expertise about these products, and take their patients' interest seriously.

"We encourage physicians to not disregard their patients' interest in these products and keep both a clinical curiosity and a healthy skepticism about the claims made," he says. "Chronic pain management continues to challenge patients and physicians, and these therapies are a promising area that needs more research. For patients struggling with chronic pain, physicians taking time to listen to them and address their questions compassionately but with an evidence-based approach can help them make informed decisions.

The variety of CBD and hemp oil products, and the limited regulation of these products, is a concern for health care professionals, according to the study. No rigorous safety studies have been done on "full spectrum" CBD oils, which contain a variety of compounds found in the hemp plant, not just CBD. The variability of state laws regarding production and distribution of hemp and CBD products adds to the complexity of decision-making for consumers and physicians.

Co-author Karen Mauck, M.D., an internist at Mayo Clinic, says there are important distinctions between marijuana, hemp and the different components of CBD and hemp oil, and some clinicians may not be aware of them.

"Other than Epidiolex, a purified form of plant-derived CBD which was approved in 2018 for treatment of severe forms of epilepsy, all other forms of CBD are not approved by the Food and Drug Administration but are sold in a variety of formulations, including oral or topical oils, creams, sprays and tablets," Dr. Mauck says. "They contain variable amounts of CBD, may contain other active compounds and may have labeling inaccuracies. Before using CBD or hemp oils, it's important to consult with your physician about potential side effects and interactions with other medications."

AUGUSTA, Ga. (Aug. 22, 2019) - An enzyme induced by stress to help reduce production of damaging free radicals is also used by liver cancer to regulate two major cell proliferation pathways that enable the cancer to thrive, scientists report.

They've also found that when they block the enzyme Nqo1, it dramatically reduces the proliferation of liver cancer cells, a hallmark of cancer's ability to survive and thrive, they report in the journal HEPATOLOGY.

Nqo1 is highly expressed in both their mouse model of liver cancer and in human liver cancer where scientists at the Georgia Cancer Center and Medical College of Georgia at Augusta University have found it acts upstream to activate the PI3K/Akt and MAPK/ERK pathways.

Both pathways are key to enabling the metabolic reprogramming that enables cancer cells' super-efficient use of glucose as fuel and ultimately their rapid replication.

Knocking out Nqo1 blocks the metabolic adaptation needed to enable liver cancer cell proliferation, says Dr. Satya Ande, molecular biologist in the MCG Department of Biochemistry and Molecular Biology and Georgia Cancer Center. "The proliferation of liver cancer cells is dramatically suppressed," he says.

Proliferation and cell survival are likely the most important functions of these key pathways, which normally function at a low, basal level, says MCG postdoctoral fellow Dr. Manali Dimri.

"Somehow these pathways are also interacting with each other via different target genes," Dimri says. "And, eventually, they are working together for cell proliferation, migration and metabolism."

Natural tumor suppressors are regularly inactivated in cancer, and Ande and Dimri also found that in liver cancer the tumor suppressor PTEN is another primary target of Nqo1, but in this case, it's turning PTEN down. One way PTEN works is directly opposed to the work of Nqo1 in liver cancer because PTEN works against the PI3K/Akt and MAPK/ERK pathways. PTEN elevation can directly combat the so-called Warburg effect, which is cancer cells' heightened use of glucose for fuel.

The fact that Nqo1 targets two -- rather than a single-- important downstream pathways, increases its value as a likely treatment target, Dimri says. The reality that Nqo1 is highly expressed in other cancers as well like breast, pancreas, ovarian and thyroid cancers, suggests it has a role in and may be a good therapeutic target for those as well, Ande says.

They started their work to find a better way to kill liver cancer by comparing normal mouse livers to cancerous ones to identify the likely long list of genes upregulated in liver cancer compared with a healthy liver. That's when they found Nqo1 was highly upregulated; and a logical next question was what the Nqo1 is doing in liver cancer, Dimri says. High expression of Nqo1 has generally been correlated with increased tumor size, a more advanced stage of cancer and ultimately decreased patient survival. But how it aids cancer cell proliferation has mostly remained a mystery.

The scientists found Nqo1 was necessary to simultaneously activate the PI3K/Akt and MAPK/ERK pathways in liver cancer, pathways already known to be hyperactive in liver cancer and known to have a lot of crosstalk.

Their findings provide more evidence of Nqo1's function as an oncogene, defined as a mutated form of a gene involved in normal cell growth that is now supporting cancer cell growth, according to the National Cancer Institute. Oncogenes can be inherited or result from environmental exposures.

Next steps include a large screening of existing drugs to see if any are adept at suppressing Nqo1. They've already tried some drugs known to suppress it and found they were good at suppressing just its enzymatic activity, its free radical scavenging, but not at impacting liver cancer's ability to replicate.

Under more normal conditions, Nqo1 works to help eliminate free radicals, unstable atoms which are generated, for example, by our use of oxygen, but which at high levels contribute to sickness and aging. Free radicals can aid cancer development, but rapidly replicating cancer cells produce a lot of free radicals, which can ultimately also damage them. Because Nqo1 has been found at high levels in so many cancers, it has been thought that it helped cancer cells survive, rather than commit suicide, by scavenging free radicals. Their evidence suggests Nqo1 has no role in scavenging free radicals in liver cancer, Ande says.

Now they also want to look at Nqo1's activity in other liver cancer models. For these studies they used the standard model, which uses a chemical to produce liver cancer and closely mimics many liver cancers in humans, but now they also want to look at other models of this condition that has diverse causes.

Risk factors for liver cancer include chronic hepatitis A or B infection that can result in a scarring of the liver called cirrhosis, which increases liver cancer risk, as well as alcohol abuse, smoking and, increasingly in this country, non-alcoholic fatty liver disease resulting from obesity, according to the American Cancer Society.

The incidence of liver cancer has tripled in the United States since 1980, according to the American Cancer Society, and the condition is three times more common in males. Liver cancer death rates have also increased, just over 2 percent per year since 2007, and it's a leading cause of death worldwide.

In order to orient themselves and survive in their environment, animals must develop a concept of their own body size. Researchers at Johannes Gutenberg University Mainz (JGU) have shown that the fruit fly Drosophila melanogaster develops a very stable long-term memory for its own body size and the reach of its extremities after it has hatched from the pupal case. The fruit fly acquires this memory through visual feedback obtained when walking, but in the first two hours after training the memory is still susceptible to the effects of stress and not yet firmly anchored. "Once the memory has consolidated, it appears from our observations that it remains intact for life," said Professor Roland Strauss of the Institute of Developmental Biology and Neurobiology at JGU. "The insects seem to have calibrated themselves for the rest of their lives." However, it is still puzzling why they are only able to access the acquired knowledge 12 hours after training. The researchers still don't know what happens in the brain in the interim.

The research group of Professor Roland Strauss uses Drosophila melanogaster to investigate memory retention and consolidation processes that are known to occur to some extent also in humans. Earlier studies have shown that the short-term memory of fruit flies declines with age and that a protein is involved in this process which is similar to that playing a role in humans.

In the new study, Tammo Krause and Laura Spindler analyzed the body-size memory of Drosophila. Fruit flies are insects that undergo a complete metamorphosis. They undergo three larval stages, during which they grow. Finally, at the end of pupation, the mature fruit fly emerges. Due to Drosophila's hard exoskeleton, the body size can no longer change; it can vary however, as the actual size of a fly is determined by the availability and the quality of food during the larval stages.

Leg-over-head behavior indicates an intention to climb

"In our recent study, we wanted to find out how the insects acquire information about their body size and remember it later," explained Tammo Krause and Laura Spindler. They observed how, under various conditions, the insects try to overcome a small gap exceeding their step size. Drosophila displays stereotypical behavior in such situations: In order to initiate the attempt to climb, the insect begins by making search movements with its forelegs lifted over the head. If the gap is far too wide, this typical behavior is not observed. The fly just turns away.

Knowledge of body size is gained through visual feedback

The results show that Drosophila learns to estimate the distance across a gap and the reach of its legs by linking visual information from the environment, such as a striped pattern, with their body size. Newly hatched fruit flies raised in the dark overestimate their body size and try to overcome gaps that are far too big significantly more frequently than animals raised in the usual light-dark cycle. The motion parallax created on the retina by structures in the surroundings when walking is used for the learning process. Another experiment in which the motion parallax was manipulated and artificially reduced during the learning process confirmed this. As a result, the flies underestimated their body size and undertook fewer climbing attempts.

"When fruit flies hatch from the pupal case and move through space, the resulting motion is captured by the eye and the fly can calibrate itself," explained Professor Roland Strauss. "Once this calibration has occurred, the knowledge is retained for life." The research team proved this in an additional experiment in which the fruit flies had to spend 21 days in the dark after three days under normal light conditions. Even after this long period, they still undertook the same number of climbing attempts as three-day-old flies. "We therefore assume that memory of their own body size is the most permanent form of recall detected in Drosophila to date," the two lead authors Tammo Krause and Laura Spindler concluded in their article in Current Biology.

Body memory only available after 12 hours

The neurobiologists discovered additional mechanisms that raise new questions. The consolidation of the memory in the first two hours after training is still stress-sensitive. This means that exposure to stress may cause it to be deleted during that period of time. Once the information learned is anchored, 12 hours must elapse after the end of training before the fruit flies can permanently access it. The researchers would now like to know what happens in the interim and how the information learned actually becomes permanently consolidated in the brain. "We are particularly interested in the epigenetic factors involved in the development of long-term memory. This is something we will be continuing to work on," said Strauss.

Matter behaves differently when it's tiny. At the nanoscale, electric current cuts through mountains of particles, spinning them into vortexes that can be used intentionally in quantum computing. The particles arrange themselves into a topological map, but the lines blur as electrons merge into indistinguishable quasiparticles with shifting properties. The trick is learning how to control such changeable materials.

For the first time, researchers have taken a microscopic look at this process. The international team has now published their results on July 11, 2019 in Communications Physics, a Nature journal.

In certain conductive materials, such as Manganese Silicon (MnSi), the quasiparticles can accumulate into a magnetic skyrmion with a vortex-like shape and motion. The skyrmion creates a lattice of connection points within the MnSi crystal.

"Magnetic skyrmions have attracted interest due to the potential for spintronics applications," said Taku Sato, study author and professor at the Institute of Multidisciplinary Research for Advanced Materials at Tohoku University.

Spintronics refer to theoretical electronics that rely not only on the charge state of a current, but also on the characteristics of electrons to transfer and store quantum information.

"The first step to realize such spintronic applications of skyrmions may be electric current control of skyrmion flow," Sato said. "Once created, the skyrmion can almost never be annihilated. It also strongly couples to electric current flow, meaning it takes very little current to move the system."

To understand how electric current affects the magnetic skyrmion changes under an electrical current, the researchers used a method called small-angle neutron scattering. They powered a neutron beam through a MnSi crystal, causing the skyrmion particles to react -- the neutrons literally scatter against and around the components of the skyrmion system. How they scatter tells the researchers about the system.

In this case, the researchers saw that the lattice structure of the skyrmion was deformed, causing the vortex motion of the skyrmion to change. They also saw that the edges of the skyrmion were significantly disturbed, almost as if it were pushing against itself. Sato attributes this to what he called "pinned edges." The skyrmion might push against its outermost limits, causing friction.

"Such a friction effect has not been reported to date as far as we are aware of," Sato said. "It's fundamental key information for the realistic spintronics device design utilizing magnetic sykrmions."

Sato and his team plan to further investigate the dynamics of magnetic skyrmions with the eventual goal of developing spintronic devices.

According to general relativity, the presence of a massive object slows down the flow of time. This means that a clock placed close to a massive object will run slower as compared to an identical one that is further away.

However, the rules of quantum theory allow for any object to be prepared in a superposition state. A superposition state of two locations is different to placing an object in one or the other location randomly - it is another way for an object to exist, allowed by the laws of quantum physics.

One of the open questions in physics is: What happens when an object massive enough to influence the flow of time is placed in a quantum superposition state?

This is a controversial topic: some physicists claim that such scenarios are fundamentally impossible - some new mechanism must block the superposition from forming in the first place - while others develop entire theories based on the assumption that this is possible.

"We started by tackling a question: what would a clock measure if it was influenced by a massive object in a quantum superposition state?" explains Magdalena Zych from the University of Queensland.

The scientists were expecting to face the roadblocks making the scenario impossible, but surprisingly, using standard textbook physics they were able to exactly describe what happens.

They so discovered that when a massive object is placed in a quantum superposition in the vicinity of a set of clocks, their time order can become genuinely quantum, defying any classical description.

Caslav Brukner, coauthor from the University of Vienna and the Austrian Academy of Sciences added that the regime where quantum time order could arise is quite remote from our everyday experience, "but the most important insight from our work is that quantum time order is at all possible, and that it results in new physical effects."

To illustrate what happens, imagine a pair of starships training for a mission. They are asked to fire at each other at a specified time, and immediately start their engines in order to dodge each other's attack. If either of the ships fires too early, it will destroy the other, and this establishes an unmistakable time order between the firing events. If a powerful agent could place a sufficiently massive object, say a planet, closer to one ship it would slow down its counting of time. As a result, the ship farther away from the mass will fire too early for the first one to escape.

The laws of quantum physics and gravity predict that by manipulating a quantum superposition state of the planet, the ships can end up in a superposition of either of them being destroyed. Such a superposition state, involving two systems, is called entangled. The new work shows that the temporal order among events can exhibit superposition and entanglement - genuinely quantum features of particular importance for testing quantum theory against alternatives. The result can now be used as a theoretical testing ground for frameworks for quantum gravity, and thus help to move forward in formulating the correct theory of quantum gravity.

The study will also be relevant for future quantum technologies. Quantum computers that exploit quantum order of performing operations might beat devices that operate using only fixed sequences. Practical implementations of quantum temporal order do not require extreme conditions--such as planets in superposition--and can be simulated without the use of gravity. The discovery of quantum properties of time can lead to better quantum devices in the upcoming era of quantum computers.

Trainee doctors who have dyslexia, and who declare this prior to taking the clinical skills component of the licensing exam for general practice, are less likely to pass than their counterparts, new research has shown.

The Clinical Skills Assessment (CSA) is a scenario based clinical exam designed to test a doctor's ability to gather information, make evidence-based decisions, and communicate effectively with patients and colleagues. The test is part of the three part qualification to become a Member of the Royal College of General Practitioners (MRCGP) which licenses doctors to practice independently as GPs.

The study led by researchers from the Community and Health Research Unit (CaHRU) at the University of Lincoln, UK in collaboration with the MRCGP, examined pass rates of 20,879 candidates who had taken the exam from 2010 to 2017 of whom 598 declared dyslexia. Findings showed that once other factors linked to exam success such as number of exams sat, initial pass mark, dyslexia, sex, ethnicity and country of primary medical qualification were taken into account, those who declared dyslexia were less likely to pass, and fared even worse if their declaration of dyslexia was delayed after failing at least once.

Interestingly, the findings of the study, which is the first to examine pass rates in the CSA, differ from a previous study into the Applied Knowledge Test (AKT) - a multiple choice written component of the MRCGP. The previous study found that dyslexia did not reduce pass rates for those declaring their learning difficulty prior to taking their exams, suggesting that the CSA may not be less problematic than written components for candidates with dyslexia as previously thought.

The study also found that candidates who declared dyslexia were more likely to be male (47.3 per cent compared with 37.8 per cent of females) and more likely to have gained their primary medical qualification outside the UK. Once other factors were taken into account, sex was not shown to have an effect on pass rates and trainee doctors from minority ethnic backgrounds were slightly more likely to pass than white British or Irish candidates.

The research has highlighted the need for further research into the aspects of the CSA exam that candidates with dyslexia find more difficult and how these challenges could be addressed to better support candidates.

Lead author Dr Zahid Asghar, from the University of Lincoln's Community and Health Research Unit said: "Doctors with dyslexia, particularly those who declare the condition after failing at least once, possibly because they are unaware of the condition or worried about declaring it, have a higher chance of failing. This suggests we need to understand more about what trainees with dyslexia find difficult about the clinical exam and what can be done to help".

Corresponding author Niroshan Siriwardena, Professor of Primary and Pre-Hospital Care at the University of Lincoln and Research Lead for Assessment at the RCGP added: "Researchers from CaHRU together with colleagues from the MRCGP exam have been investigating differential attainment in the exam and its causes for some time, and our research is beginning to reveal important clues about why certain groups of doctors do less well at certain parts of the exam and what might be done to alleviate this."

Only at extremely low temperatures does order prevail. At the Vienna University of Technology, materials are cooled to almost absolute zero, so that electrons, which otherwise occupy different states quite randomly, show certain regularities. But even the behaviour of such extremely cold electrons is difficult to understand, on the one hand because the electrons strongly influence each other and cannot be described separately, and on the other hand because different electron characteristics play a role at the same time. However, the understanding is now made easier by experiments at TU Wien: It was possible to influence different characteristics of the electrons separately from each other. Closely interwoven quantum phenomena can thus be understood individually. The results have now been published in the journal PNAS.

Chess pieces and electrons

Imagine we have a big bag of chess pieces that you place on a chess board one after the other until it is full. There are different ways to create ordered patterns: For example, you can always place a white and a black piece alternately. You can also ignore the colors and alternately place a knight and a rook, or think up more complicated order patterns that combine color and figure type.

It is similar with electrons in a solid: As in a chessboard, there are regularly arranged places where electrons can sit. And like chess pieces, electrons have different properties that can be used to create order.

"The simplest property of the electrons is their charge - it is responsible for the flow of electric current. However, the charge is the same for all electrons," says Prof. Silke Bühler-Paschen from the Institute of Solid State Physics at the TU Vienna. "Things become more interesting if we also consider the electron spin. For the spin, there are always two different possibilities. Its magnetic properties are determined by the regular arrangement of electron spins in a solid body".

Where is the electron located? The orbital degree of freedom

However, for localized electrons there is another property, another degree of freedom, which plays an important role: The orbital degree of freedom. If an electron is bound to a certain atom, different spatial arrangements are possible. Quantum physics allows for different geometric relationships between electron and atom - and this also allows for ordered structures in the solid, for example when many identical atoms are arranged in a crystal, and each has an electron that is in the same orbital state.

"We investigated a material made of palladium, silicon and cerium," says Silke Bühler-Paschen. "We focus on the electrons located at the cerium atom and on the conduction electrons, which can move freely through the crystal." With the help of conduction electrons, it is possible to influence the order of the electrons at the cerium atom - both their spin degree of freedom and their orbital degree of freedom. "This is done by shielding," explains Bühler-Paschen. "The conduction electrons can virtually hide both the spin and the orbital state of the fixed electrons, which is called the Kondo effect. This means that order is no longer possible." As has now been shown, the order of these two degrees of freedom can be switched on and off separately at very low temperatures - with the help of tiny magnetic field changes.

"The fact that order in quantum systems collapses or reappears in certain situations is not new," says Silke Bühler-Paschen. "But here we have a system in which the order can be switched on and off individually in relation to two different degrees of freedom that are closely interwoven at high temperatures - and that is quite remarkable."

This possibility could now help to uncover particularly interesting properties of complex materials. "There are reasons to assume that the orbital degree of freedom also plays an important role in the phenomenon of unconventional superconductivity," says Silke Bühler-Paschen. "We now have a new instrument at our disposal to better understand such technologically important effects.

Exposure to toxic air pollutants is linked to increased cardiovascular and respiratory death rates, according to a new international study by researchers from Monash University (Australia) and abroad.

The study, led by Dr Haidong Kan from Fudan University in China, analysed data on air pollution and mortality in 652 cities across 24 countries and regions, and found increases in total deaths are linked to exposure to inhalable particles (PM10) and fine particles (PM2.5) emitted from fires or formed through atmospheric chemical transformation.

Published in the New England Journal of Medicine, it's the largest international study to investigate the short-term impacts of air pollution on death, conducted over a 30-year period.

Associate Professor Yuming Guo from Monash University's School of Public Health and Preventive Medicine in Australia, said as there's no threshold for the association between particulate matter (PM) and mortality, even low levels of air pollution can increase the risk of death.

"The adverse health effects of short-term exposure to air pollution have been well documented, and known to raise public health concerns of its toxicity and widespread exposure," Professor Guo said.

"The smaller the airborne particles, the more easily they can penetrate deep into the lungs and absorb more toxic components causing death.

"Though concentrations of air pollution in Australia are lower than in other countries, the study found that Australians are more sensitive to particulate matter air pollution and cannot effectively resist its adverse impacts. This may be attributed to Australians' physiological functions having adapted to living in areas with low levels of particulate matter air pollution.

"Given the extensive evidence on their health impacts, PM10 and PM2.5 are regulated through the World Health Organisation (WHO) Air Quality Guidelines and standards in major countries, however Australians should pay more attention to the sudden increase in air pollution," Professor Guo said.

The results are comparable to previous findings in other multi-city and multi-country studies, and suggest that the levels of particulate matter below the current air quality guidelines and standards are still hazardous to public health.

Scientific papers go through a peer-review process before they are accepted for publication in a journal. They are sent to two or more independent researchers for comment. Those researchers are asked to assess the robustness of the methods used and the conclusions drawn, as well as the novelty of the study. The reviewers' comments play an important role in determining which papers get accepted and published.

Currently the most common process in ecology journals is single blind peer review. The authors of a submitted research paper are not told who the reviewers are: they are 'blind' to their identity. The reviewers, however, do see the authors' details on the papers they check.

This has led to concerns that, consciously or unconsciously, knowledge of an author's gender, university position or nationality could influence how reviewers assess the research reported in the paper.

For example, there is some mixed evidence to suggest research led by female authors may not score as highly in peer review. On the other hand, papers by well-known authors or those from prestigious institutions may get an easier ride.

As a result, some journals have introduced 'double-blinding'. This is where the reviewers are 'blinded' as well: the list of authors is removed from the paper they look at.

Beginning 5 September, the British Ecological Society will conduct a large-scale randomised controlled trial over the next two years to compare the two approaches to peer review. An estimated 2500 research papers submitted to the journal Functional Ecology will be randomly allotted into two workflows: single- or double-blind peer review. The study will assess whether author characteristics affect peer-review scores and acceptance of papers, as well as the effectiveness of the blinding process.

In particular, the study will examine whether double-blinding reduces variation in peer review scores and acceptance rates among authors of different genders, geographic locations, first languages (English vs. other), university prestige, career stages (junior vs. senior) and publishing histories (more prolific, higher prestige).

The journal will also investigate how anonymising authors influences the publishing process - in its ability to recruit reviewers, the quality of reviews received, the average rating given to papers and the ability of reviewers to identify authors. Finally, authors and reviewers will be asked to complete a survey of their opinions on single- and double-blind peer review.

Charles Fox, Executive Editor for Functional Ecology, said: "It's critical for science, and for the scientists involved, that the research which gets published is selected through a fair and unbiased process. We know that people are concerned bias in peer review can act against female researchers and those from developing countries. As scientists, we should seek to base our processes on the best evidence. That's why we're carrying out this trial. The results will help determine the best ways of minimising sources of potential bias in the publishing process."

Catherine Hill, Director of Publishing at the British Ecological Society, said: "The British Ecological Society is committed to improving openness and inclusivity in our science. We have six leading journals publishing the latest in ecology. It's vitally important that the research we publish is reviewed and selected in the most impartial way, regardless of the authors' backgrounds. This study will provide important data on whether we are achieving this aim and ensure our peer review policy is based on the best possible evidence."

The introduction of China's universal two-child policy, that permits all couples to have two children, has led to an extra 5.4 million births, finds a study in The BMJ today.

It is the first study to use national data to estimate the impacts of the policy change and shows that births increased in response to the policy, but not as much as some policymakers had hoped.

China's two-child policy, announced in October 2015, was enacted to reverse the nation's stagnant population growth, ageing population, and shrinking workforce.

The policy targeted some 90 million women of reproductive age who already had a child, and now would be allowed to have a second child.

There has been much speculation about the impact of the policy, with projections ranging from slightly over 1 million to more than 20 million annually. But, so far, studies have been limited.

So a team of researchers based in China and the US set out to measure changes in births and health-related birth characteristics associated with the policy change.

Using two national databases, they compared the number of births in two phases: "baseline period" (up to and including June 2016, 9 months after the announcement) and "effective period" (July 2016 to December 2017).

Their findings are based on 67.8 million births in 28 out of 31 provinces of mainland China, an average of 1.41 million births per month.

The researchers estimate an additional 5.4 million births as a result of the new policy during the first 18 months that it was in effect. And for the first time, the number of births to those who had given birth previously (multiparous mothers) exceeded births to first-time (primiparous) mothers.

The policy was also associated with a 59% average increase in births to older mothers (35 years or older), but there was no accompanying increase in premature births.

Finally, there was a slight decrease in caesarean deliveries to primiparous mothers, which might signal a favourable trend towards vaginal birth in first-time mothers in China, explain the researchers.

However, they point out that many of the changes associated with the policy, including the increase in births, appeared to diminish at the end of the study period, raising questions about whether the policy's effects will be sustained.

This is an observational study, so can't establish cause, and the researchers outline some limitations relating to the validity and representativeness of the data. But they say their findings clearly show that births increased in response to the policy, albeit not as much as some policymakers had hoped.

Although they found no significant increased premature births, they say "more work is needed to document and ensure the health of an increasingly older maternal population of second-time mothers in a nation where caesarean delivery rates are high."

Further research is also needed "to develop a more nuanced understanding of the sustained impact of this historic change on the world's largest nation," they conclude.

Scientists have combined analyses from honey and salmon to show how lead from natural and industrial sources gets distributed throughout the environment. By analysing the relative presence of differing lead isotopes in honey and Pacific salmon, Vancouver-based scientists have been able to trace the sources of lead (and other metals) throughout the region. Scientists in France, Belgium and Italy are now looking to apply the same approach to measure pollutants in honey in major European cities. The research* is being presented at the Goldschmidt conference in Barcelona.

Scientists have long known that honey bees pick up small amounts of metal elements (i.e., iron, zinc, and pollutants such as lead, and cadmium) when they alight on flowers and leaves. They carry these metals back to the hive where tiny amounts are incorporated into the honey. However, this is the first time researchers have been able to establish clearly the sources of the metals carried by the bees and their products, making them reliable biomarkers for environmental pollution.

"We've found that we can let the bees do the hard the work for us: they go to thousands of sites where metal-containing dust particulates might land, then bring samples back to a central hive. From there we can take the honey to have it analysed and begin to identify the source of pollutants like lead" said Ph.D. candidate Kate Smith, part of a team working at the Pacific Centre for Isotopic and Geochemical Research (University of British Columbia).

Once they have sampled the honey gathered by the bees, it is taken to a specialised geochemistry lab to be analysed using a high-resolution ICP-MS (Inductively coupled plasma mass spectrometry) instrument. This allows scientists to distinguish between different types (isotopes) of certain metal pollutants, like lead.

Smith continued, "Looking at the lead isotopic composition of the honey samples, we can tell the difference between honey gathered in the city centre of Vancouver and honey gathered in rural areas. We see that the trace amounts of lead in urban honey samples contain higher 208Pb/206Pb ratios that have no local natural equivalent, indicating that they come from man-made sources like aging city infrastructure and fuel combustion (e.g. cars and ships). Lead ratios measured in rural honey, on the other hand, reflect those of natural sources, like the local geology or particulates from nearby forest fires."

Presenting the work on salmon, postdoctoral researcher Dr. Miling Li added "This work with honeybees is mirrored in initial findings from shellfish and salmon. Juvenile salmon breed and live in remote freshwater ecosystems in British Columbia, and their lead composition reflects that found in nature, e.g. the nearby Garibaldi volcano range. Adult salmon that forage in the open ocean off the BC coast reveal isotopic compositions consistent with downtown Vancouver honeys. This indicates that Pacific salmons were exposed to lead during their sea life mostly from anthropogenic sources in the Northeast Pacific Ocean."

Although we can identify the sources of lead, the lead concentrations in both the honey and salmon from Vancouver and the surrounding areas are extremely low and well below the reported world-wide average of lead in honey.

Following the proof of concept work in Metro Vancouver (and similar work in Australia, in Sydney and the site of the vast Broken Hill lead mines, the main source of lead added to gasoline in Europe, Asia and many other places in the world), the UBC team has now developed standardised protocols for measurement of lead isotopes in honey to apply the technique to other cities. Experiments are now being set up in Paris, Brussels, and Piacenza, with interest also coming from the U.S. Simultaneously, the UBC team is confirming the efficacy of the Vancouver honey data by monitoring topsoil and air quality near the hives.

Kate Smith said, "Honey is particularly useful because honeybees can be found pretty well everywhere, so we believe that using honey as a proxy measurement for lead pollution may become an important urban geochemistry and environmental tool. This means we need to make sure that we have a framework that gives results of consistent quality from year to year and city to city. This is what we are now testing."

Research team leader Professor Dominique Weis said "Urban geochemistry has become an important discipline in understanding the spread of heavy metal pollutants in cities, as long as the natural background is well characterized. Lead isotopic analysis is a standard geochemical method that for decades provided a signal dominated by lead that was used as an additive in gasoline. Honey is an effective biomonitor, and allows us to identify the source of some pollutants even at very low levels; we think that this method could become an internationally accepted way of assessing metal sources and distribution in urban environments".

Airborne lead pollution varies significantly from area to area. It is found naturally at low levels. Major sources of pollution are metal processing, incinerators, and other industrial processes. Lead in gasoline was banned in the 1990s in North America, which caused a significant decrease in airborne lead levels (98% in the USA). Depending on the level of exposure, lead can have significant health effects**.

Commenting, Professor Mark P Taylor***, Macquarie University, Australia, leader of the Australian group working on honey said,

"This research is emblematic of contemporary science because it touches on two emerging key public interests in an increasingly urbanised world: it examines environmental quality by way of assessing anthropogenic changes to trace element sources in the wider environment and it engages citizens directly through the collection and sharing of honey for geochemical analysis. Nothing could be sweeter for science."

This is an independent comment; Professor Taylor was not involved in this work.

Many forms of vision loss stem from a common source: impaired communication between the eye and the brain. And at the root of all eye-to-brain communication are the hundreds of proteins generated by the retina's nerve cells.

A new study from Scripps Research, which appears this month in Cell Reports, examines these proteins in unprecedented detail--providing surprising new insights into how visual signals are distributed to different regions of the brain. The results are an important first step in understanding and eventually treating vision loss from glaucoma, multiple sclerosis or even trauma. More than 3.3 million Americans aged 40 years and older are either legally blind or have visual impairments that can't be corrected with today's interventions, according to the Centers for Disease Control and Prevention.

"Proteins are usually the targets of drugs--so if you want to design a drug that will help communication between the eye and the brain, it helps to know what proteins those drugs would target," says Hollis Cline, PhD, co-chair of Scripps Research's Department of Neuroscience, who led the research project. "This type of study was never possible before because it wasn't feasible to see how these proteins move around the brain. The technology didn't exist."

To create the technology, Cline's lab worked closely with the lab of John Yates III, PhD, a Scripps Research chemist who has pioneered new ways to use an analytical technique known as mass spectrometry to study proteins and their functions. Using this new method--developed over the course of several years--Cline's team was able to "label" about 1,000 different types of proteins that originate in the eye's retinal ganglion cells, and then watch how and where they travel in a living brain of a rat. Just as in human brains, the proteins are transported via neuronal axons, which are long, threadlike nerve fibers that extend from the eye into the brain via the optic nerve.

"The brain is an ensemble of very complicated architecture, and it's hard to separate every component and study the pieces individually," says Lucio Schiapparelli, PhD, a neuroscientist in Cline's lab and a lead author of the study. "Our methodology allowed us examine the visual system in a way that had not been studied before so we could observe the molecules independently and analyze their biochemistry."

Going into the study, Cline said she was curious whether similar types of proteins would travel to distinct targets within the brain. The retina projects proteins into more than 30 different areas of the central nervous system, but for the study, her team chose to evaluate the two major targets: the superior colliculus (which analyzes motion in the visual field and controls goal-directed head and eye movements), and the lateral geniculate nucleus (which analyzes the shape of objects we see and sends that information to a higher brain area, the visual cortex).

While previous studies identified various proteins produced in the retina, the ultimate destination of these proteins was largely unknown. The optic nerve was an especially important focus of study, as it is implicated in so many devastating eye diseases.

"We were surprised right from the start to find proteins in the axons of the optic nerve that everybody previously thought would be functioning only in the eye," Cline says. "These are proteins that are usually in the nucleus of a cell, but we found them far, far away from the nucleus, participating in some form of communication."

This finding, Cline says, has already fueled new research on how these proteins may influence health and disease. Because this type of neuronal protein exists in other parts of the body, it may play a role in other nerve-cell communication disorders such as Charcot-Marie-Tooth disease.

The optic nerve is the information highway from the eye to the brain, sending signals to different destinations. But the team discovered that that similar proteins didn't always share a common destination. Rather, many proteins were transported preferentially to one brain region, while some were transported to all of the regions studied.

"Understanding the transport of these proteins out of the retina is essential to understand how the visual system functions," Cline says. "This can help us study what happens when a person experiences nerve damage and vision loss--and will hopefully lead us to treatments that can enhance protein transport and prevent cells from dying."