Culture

People around the world consume rice in their daily diets. But in addition to its nutrient and caloric content, rice can contain small amounts of arsenic, which in large doses is a toxin linked to multiple health conditions and dietary-related cancers.

Now researchers at the University of Washington have found that warmer temperatures, at levels expected under most climate change projections, can lead to higher concentrations of arsenic in rice grains. The team will present these findings Dec. 10 at the American Geophysical Union's Fall Meeting in San Francisco.

"We know that more arsenic is released from soil at higher temperatures. Here we saw this response to temperature in the soil impact the arsenic content of rice grain," said senior author Rebecca Neumann, a UW associate professor of civil and environmental engineering. "We were working with soil that had relatively low arsenic levels, but the warmer temperatures still led to increased arsenic concentrations in the grains at ranges where we begin to have health concerns. If these results are representative of what we might expect for field-grown rice, then climate change could exacerbate the problem of arsenic-contaminated rice."

Arsenic occurs naturally in the soil, though its concentration is higher in areas that have historically used arsenic-based herbicides or where irrigation water contains arsenic. When farmers grow crops like rice under flooded conditions, arsenic is drawn out of the soil and into the water.

"In general, the plant is like a big tube or a straw as it draws water up from its roots to its leaves. And rice naturally takes up arsenic because the arsenic mimics other molecules that these plants preferentially draw out of the soil," said lead author Yasmine Farhat, a UW doctoral student in civil and environmental engineering. "It's a perfect storm for concentrating arsenic."

To determine whether rice would draw up more arsenic under warmer conditions, the team collected soil from a paddy field in Davis, California. Back in Seattle, the researchers grew rice in this soil in temperature-controlled growth chambers.

They compared arsenic uptake under four different temperature conditions. Some plants were grown under normal conditions for that part of California: 77 degrees Fahrenheit (25 C) on average during the day. Others were grown at incrementally warmer temperatures reflecting different potential levels of warming for that region by the end of this century: 82 F (28 C), 87 F (30.5 C), and 91 F (33 C). Night time temperatures were 3.6 F (2 C) cooler than daytime for all plants.

As the temperature increased, the team saw increased uptake of arsenic to every part of the plant the researchers looked at -- including the rice grains.

"For the stem and the leaves, it's a clear step up in arsenic concentration as we increase the temperature," Farhat said. "For the grains, the highest temperature made the plants so stressed out that they didn't produce any grains. But these other two forecasts of increasing temperature show a similar increase of arsenic in the rice grains. Arsenic concentrations in the grain more than tripled between the low- and high-temperature treatments."

Arsenic is a toxin for rice plants too, and they have mechanisms to protect themselves against higher levels of it. One method includes turning on a protein that sequesters arsenic in specific cells and tissues of plant. But when the researchers measured expression levels of this protein in their plants at higher temperatures, they saw no difference compared to the plants grown at today's relatively low temperatures.

"Maybe the arsenic concentration was so low in our soil that the plant wasn't 'aware' it needed to turn on its defense mechanism," Farhat said. "We haven't been as concerned about these low-arsenic systems, but our data suggest that as temperatures start to warm, even rice grown in soil with low arsenic could be at risk for having higher levels of arsenic in the grains."

Some forms of arsenic are more toxic than others. The team is now collaborating with researchers at UW Tacoma to develop a method that would allow them to see what forms of arsenic are in the different parts of the plant. That way, they can get a better picture of any potential health risks to people.

"Arsenic in all forms is bad for us, and it's bad for the plants as well," Farhat said. "Increasing arsenic can decrease crop yield. That can be economically bad for rice farmers. I want people to remember even if they are not eating a lot of rice, a lot of people are heavily relying on this crop. When we're thinking and planning for the future, we need to remember that rice touches a lot of people and we should work together on that."

It pays to be the boss.

According to new research from Duke University's Fuqua School of Business, it pays even more to be an incumbent CEO working with a newly hired chief financial officer (CFO).

Fuqua researchers studied more than 20 years of data from S&P 1500 firms and found CEOs took home an average of 10% more compensation when working with a CFO who was hired after them, also known as a "co-opted" CFO.

The study, "CFO Co-option and CEO Compensation," is forthcoming in the INFORMS journal Management Science and offers quantifiable insights into a phenomenon that is difficult to document - the influence CEOs have on colleagues who could potentially increase their pay.

Previous research has shown CEOs may exert influence up their chain of command on a co-opted board; specifically, when newly appointed board members work with an incumbent CEO, the board's oversight is also weaker and CEO compensation is as much as 20% higher.

The Fuqua study examines the impact CEOs also may have leaning down the chain of command on their CFOs.

"CEOs ultimately have power over CFOs, arguably more so when the CEO played a role in hiring the CFO," said Bill Mayew, a Fuqua accounting professor and co-author of the study. "They may pressure CFOs to manage earnings to help the firm meet, or just barely beat, earnings targets from financial analysts. Those reported earnings and the response in stock prices can then drive up a portion of the CEO's compensation based on the firm's performance."

With CEOs in the study earning a median pay package of $3.19 million a year, a 10% premium for incumbent CEOs was upwards of $300,000, compared to CEOs working with CFOs hired by their predecessors.

CEOs were most likely to see the higher pay during the first three years of the co-opted CFO's tenure, when the CFO may have been most amenable to the CEO's influence, Mayew said.

"If you're a brand new CFO, you don't want to displease your boss and risk getting fired," Mayew said. "Over time, a CFO builds up allies in the firm, which might give them more power to voice their opinion and apply accounting rules neutrally rather than pushing the boundary."

Measuring what happens behind closed doors

For proprietary, legal and logistical reasons, it's difficult for researchers to observe day-to-day interactions between CEOs and CFOs and pinpoint direct causes for higher CEO compensation.

Instead, they used nearly 18,000 data points from 1993 to 2015 illustrate an association between co-opted CFOs and CEO compensation. The data show that co-opted CFOs helped firms achieve analyst-based earnings targets through earnings management, which is consistent with CFOs exercising discretion in their area of expertise, said co-author John Heater, a Fuqua assistant professor in accounting.

CFOs change tactics

Patterns in the data before and after passage of the Sarbanes-Oxley Act (SOX) in 2002 offered more evidence of these strategies when CFOs "predictably shifted how they delivered benchmark-beating earnings," Heater said.

Prior to the tighter regulations and scrutiny of SOX, CFOs had more discretion when reporting firm earnings, such as adjusting estimates or reported accruals to meet earnings targets.

When SOX increased regulatory pressure on CFOs, accounting practices shifted from adjusting estimates on paper to actually making different business decisions to move numbers, known as real earnings management, Heater said.

"Managers can decide to run their operations differently, and in a way that promotes short-term earnings, such as cutting spending on research and development, or via overproduction or other methods that boost profits today, but can hurt the firm tomorrow," Heater said.

"This may not be an immediate concern to corporate executives who, based on their average tenure, may not be around in the long-run to face the negative implications of their decisions," he said. "This is why it's so important that boards and their hiring committees be cognizant that this power dynamic between the CEO and CFO exists, and to consider that when hiring and overseeing these roles."

Moderating influence in the C-suite

For CFOs who find themselves subject to undue pressure from a CEO, Mayew encourages them to establish support within the firm.

"Get connected, make friends, and ask questions in a way that puts your voice out there more broadly within the firm," he said. "This is much easier to do today than it was 20 years ago because communication technology improvements have made connecting much easier. Responses from colleagues can help calibrate who's willing to listen and who's willing to stand up against undue pressure in the organization."

Board members who are concerned about undue influence in the CEO-CFO relationship might assess how factors such as board oversight and the structure of the CEO's contract may encourage or dissuade this type of behavior, Mayew said.

"Assess what mechanisms you have in place for a CFO to voice concerns if they're uncomfortable," Mayew said. "There are systems boards can put in place that, in some sense, could lessen the pressure."

ANN ARBOR--Our closest-ever look inside the sun's corona has unveiled an unexpectedly chaotic world that includes rogue plasma waves, flipping magnetic fields and distant solar winds under the thrall of the sun's rotation, according to University of Michigan researchers who play key roles in NASA's Parker Solar Probe mission.

The U-M findings, part of the first wave of results from the spacecraft that launched in August 2018, provide important insights into two fundamental questions the mission was designed to answer: Why does the sun's corona get hotter as your move further away from the surface? And what accelerates the solar wind--an outward stream of protons, electrons and other particles emanating from the corona.

Both questions have ramifications for how we predict, detect and prepare for solar storms and coronal mass ejections that can have dramatic impacts on Earth's power grid and on astronauts.

"Even with just these first orbits, we've been shocked by how different the corona is when observed up close," said Justin Kasper, a professor of climate and space sciences and engineering at U-M who serves as principal investigator for Parker's Solar Wind Electrons Alphas and Protons (SWEAP) instrument suite.

"These observations will fundamentally change our understanding of the sun and the solar wind and our ability to forecast space weather events."

Findings from data collected during the spacecraft's first two encounters with the sun will be published in four papers in Nature on Dec. 4. Kasper led one of the studies and is co-author of two others.

Solar wind acceleration findings

The spacecraft revealed that the sun's rotation impacts the solar wind much farther away than previously thought. Researchers knew that close in, the sun's magnetic field pulls the wind in the same direction as the star's rotation. Farther from the sun, at the distance the spacecraft measured in these first encounters, they had expected to see, at most, a weak signature of that rotation.

"To our great surprise, as we neared the sun, we've already detected large rotational flows--10 to 20 times greater than what standard models of the sun predict," Kasper said. "So we are missing something fundamental about the sun, and how the solar wind escapes.

"This has huge implications. Space weather forecasting will need to account for these flows if we are going to be able to predict whether a coronal mass ejection will strike Earth, or astronauts heading to the moon or Mars," Kasper said.

Coronal heating findings

Parker Solar Probe's findings regarding the sun's magnetic field--which is believed to play a role in the coronal heating mystery--were equally surprising. From Earth's vantage point, magnetic oscillations called "Alfvén waves" were detected in the solar wind long ago. Some researchers though they may be remnants of whatever mechanism caused the heating phenomenon.

Parker researchers were on the lookout for indications that might be the case, but found something unexpected.

"When you get closer to the sun, you start seeing these 'rogue' Alfvén waves that have four times the energy than the regular waves around them," Kasper said. "They feature 300,000 mph velocity spikes that are so strong, they actually flip the direction of the magnetic field."

Those polarity-reversing velocity spikes offer another potential candidate for what may cause the corona to get hotter moving away from the sun.

"All of this new information from Parker Solar Probe will cause a fundamental rethinking of how the magnetic field of the Sun behaves and is coupled to the acceleration of the solar wind," said Lennard Fisk, the Thomas M. Donahue Distinguished University Professor of Climate and Space Sciences and Engineering.

Children with food allergies are seen 10 months sooner and have fewer allergic reactions when treated by a paediatrician in their own community, a new study shows.

The trial, led by the Murdoch Children's Research Institute (MCRI) and published in Allergy: European Journal of Allergy and Clinical Immunology, saw specially trained paediatricians working in community clinics, where they could provide front-line allergy treatment and management advice. Children with three or fewer suspected food allergies took part in the trial while those with suspected anaphylaxis (a more severe type of food allergy) or more than three food allergies were excluded.

The trial resulted in faster assessment times, was more acceptable to families, and delivered similar quality of allergy care to specialist hospital-based clinics.

Based on these results, the trial team is calling for investment in a larger program to train community paediatricians, especially in regions where there are no child allergy specialists.

Lead author, MCRI's Professor Harriet Hiscock, said 63 per cent of those seen by a paediatrician in the community were treated without needing an allergist referral, freeing up valuable hospital resources.

"As rates of food allergy rise, specialist allergy services are valiantly struggling to manage demand, but waiting times to access these services are long," Professor Hiscock said.

"In many regions around Australia, allergy care is primarily delivered by allergists, due to limited allergy training opportunities for general pediatricians and primary care physicians."

Research shows 10 per cent of infants and 4 to 8 per cent of children have a proven food allergy in Australia, a five-fold increase in the past decade.

Professor Hiscock said the study, which involved children aged 0-12 years, was the first to evaluate this community-based approach. A key component of the program is providing specialised allergy training to general pediatricians.

The study found out of the 115 participants in the community group, 81 per cent saw a pediatrician by 12 months. This compared to 28 per cent of 181 patients who received care at the RCH Allergy Clinic. Of these, 60 per cent had not received an appointment at 12 months.

Time to assessment was also shorter, 2.4 months for a community paediatrician compared to 12 months for a hospital allergist.

Professor Hiscock said children in the community group reported fewer reactions to food and families were more satisfied with the overall process.

Researchers from The Royal Children's Hospital, the University of Melbourne and Montreal Children's Hospital also contributed to the findings.

Researchers at CSIRO, Australia's national science agency, QUT and Queensland Health have developed a new tool to predict the global spread of human infectious diseases, like dengue, and track them to their source.The tool draws on travel data from the International Air Transportation Association and dengue incidence rates from the Global Health Data Exchange to derive new insights about the spreading dynamics of dengue, a mosquito-borne disease.

Dr Jess Liebig, postdoctoral fellow at CSIRO's data science arm Data61, said international travel significantly contributes to the rapid spread of dengue from endemic to non-endemic countries.

"According to the World Health Organisation, around half the world's population is at risk of contracting dengue," Dr Liebig said.

"By understanding the travel behaviour of infected individuals, we can estimate the number of infections that are imported into different countries each month.

"The tool also determines the infections' country of origin and is able to uncover the routes along which dengue is most likely spread,"

In non-endemic countries such as Australia, local outbreaks are triggered by individuals who acquire the disease overseas and transmit the virus to local mosquitoes.

Professor Raja Jurdak, QUT, said that in many locations, infected individuals are not diagnosed, and dengue can be under-reported to health authorities, making it challenging to monitor risk and prevent the spread of infection.

"According to recent studies, around 92 per cent of symptomatic infections are not reported to health authorities mainly due to low awareness levels and misdiagnosis," Professor Jurdak said.

"Our tool is one of the first to be able to forecast the absolute number of dengue importations, rather than the relative risk, at a global level."

The tool identifies the travel route from Puerto Rico to Florida as having the highest predicted volume of dengue-infected passengers travelling to a non-endemic region.

"This provides a useful tool to assist public health authorities with dengue preparedness," Dr Cassie Jansen, researcher at Queensland Health said.

"It can also help authorities to identify those locations where new dengue outbreaks may occur, following the arrival of infected passengers."

The tool can be applied to other vector-borne diseases of global concern such as malaria, Zika and chikungunya.

It expands on previous work, which modelled how dengue infections from overseas might spread in Australia.

The research is part of the Disease Networks and Mobility (DiNeMo) project aimed at developing a real-time alert and surveillance system for human infectious diseases.

An earlier model was developed to predict the spread of dengue within Australia.

DiNeMo combines CSIRO's expertise in health and biosecurity with the deep technology capabilities of its data science arm, Data61.

CHICAGO - Focused ultrasound is a safe and effective way to target and open areas of the blood-brain barrier, potentially allowing for new treatment approaches to Alzheimer's disease, according to initial study results presented at the annual meeting of the Radiological Society of North America (RSNA).

There currently is no effective treatment for Alzheimer's disease, the most common cause of dementia. The blood-brain barrier, a network of blood vessels and tissues that keeps foreign substances from entering the brain, presents a challenge to scientists researching treatments, as it also blocks potentially therapeutic medications from reaching targets inside the brain.

Studies on animals have shown that pulses of low-intensity focused ultrasound (LIFU) delivered under MRI guidance can reversibly open this barrier and allow for targeted drug and stem-cell delivery.

Researchers at three sites have been studying LIFU in humans for more than a year in a clinical trial led by Ali Rezai, M.D., director of the West Virginia University (WVU) Rockefeller Neuroscience Institute in Morgantown, W.Va. For the new study, researchers delivered LIFU to specific sites in the brain critical to memory in three women, ages 61, 72 and 73, with early-stage Alzheimer's disease and evidence of amyloid plaques--abnormal clumps of protein in the brain that are linked with Alzheimer's disease. The patients received three successive treatments at two-week intervals. Researchers tracked them for bleeding, infection and edema, or fluid buildup.

Post-treatment brain MRI confirmed that the blood-brain barrier opened within the target areas immediately after treatment. Closure of the barrier was observed at each target within 24 hours.

"The results are promising," said study co-author Rashi Mehta, M.D., associate professor at WVU and research scholar at West Virginia Clinical and Translational Science Institute. "We were able to open the blood-brain barrier in a very precise manner and document closure of the barrier within 24 hours. The technique was reproduced successfully in the patients, with no adverse effects."

MRI-guided LIFU involves placement of a helmet over the patient's head after they are positioned in the MRI scanner. The helmet is equipped with more than 1,000 separate ultrasound transducers angled in different orientations. Each transducer delivers sound waves targeted to a specific area of the brain. Patients also receive an injection of contrast agent made up of microscopic bubbles. Once ultrasound is applied to the target area, the bubbles oscillate, or change size and shape.

"The helmet transducer delivers focal energy to specified locations in the brain," Dr. Mehta said. "Oscillation of the microbubbles causes mechanical effects on the capillaries in the target area, resulting in a transient loosening of the blood-brain barrier."

LIFU could help deliver therapeutic drugs into the brain to improve their effectiveness. Even without drugs, opening of the brain-blood barrier in animals has shown positive effects, Dr. Mehta said. These effects may be due to increased flow of the fluid that cleans the brain of toxic substances, from an immune response triggered by the opening, or by some combination of the two.

While the research so far has focused on the technique's safety, in the future the researchers intend to study LIFU's therapeutic effects.

"We'd like to treat more patients and study the long-term effects to see if there are improvements in memory and symptoms associated with Alzheimer's disease," Dr. Mehta said. "As safety is further clarified, the next step would be to use this approach to help deliver clinical drugs."

It's time to stop the endemic financial entanglement with industry that is distorting the production and use of healthcare evidence, causing harm to individuals and waste for health systems, argue an influential group of international experts in The BMJ today.

The group proposes "pathways" towards financial independence from industry across healthcare,"to build a more trustworthy evidence base to inform healthcare decisions.

Their call to action comes against a backdrop of growing evidence of the problem of "too much medicine" - the threat to health and the waste of money caused by overdiagnosis and unnecessary care.

"If we want to produce trustworthy evidence and tackle the epidemic of medical excess, decision-makers at all levels within healthcare need to disentangle themselves from those profiting from that excess," said lead author, Dr Ray Moynihan, Assistant Professor at Bond University in Australia.

Today's article marks the launch of a BMJ themed collection on commercial interests, transparency and independence at the Preventing Overdiagnosis conference in Sydney Australia on 5-7 December 2019, where Dr Fiona Godlee, The BMJ's Editor in Chief, will deliver a keynote presentation.

"Patients and the public deserve to have evidence they can trust," said Dr Godlee. "Commercial influence has no place in scientific research, nor in the education and guidance of clinicians, nor in decisions about diagnosis and treatment. We hope that people around the world support our call for fundamental reforms."

Over the coming months, articles will be added to the collection to help better understand the nature of commercial conflicts of interest, to explore when involvement with industry is necessary, and to share examples of progress towards independence.

The proposals for fundamental cultural change were developed by a global group from eight nations, with expertise across medicine, the law and philosophy. It includes leading researchers, regulators, citizen health advocates, and doctors, including the president-elect of the World Organisation of Family Doctors.

The group point to examples across medical research, education and practice, from around the world, where individuals and organisations are shifting to independence from commercial influence, demonstrating that change is not only necessary but also feasible.

Proposed pathways to independence outlined in The BMJ today include governments requiring independent testing of new treatments and technologies; policies to ensure only education that is free of industry support will count towards to health professional accreditation; and a move to reliance on clinical guidelines produced and written by groups free from financial relationships with industry.

These proposed pathways "are not comprehensive or definitive, but rather designed to encourage the development of more detailed practical recommendations for change, and how to fund it, involving players across healthcare," explain the authors.

"Such transformation will be slow, but may be unstoppable, because human health, the sustainability of our health systems, and trust in medical science will be the beneficiaries," they conclude.

The BMJ is also offering others the chance to endorse the call to action, and to become involved in the development of more detailed recommendations for change.

Fish will mate with a species outside their own if the male's colouring is attractive enough or if the female can't see him properly, according to new research.

Such 'mistakes' in mate choice can lead to the evolution of new species, an international team of scientists found. The group studied 2000 fish and analysed the DNA of more than 400 cichlid fish from two freshwater lakes in East Africa. They discovered more than 40 new species in Lake Mweru, which formed around one million years ago.

Dr Joana Meier, an evolutionary biologist at St John's College, University of Cambridge, and lead author of the research published today (December 3 2019) in Nature Communications, said: "We found a dazzling variety of ecologically diverse new species - called radiations - that were previously unknown.

"The new species of cichlids adapted to use all the available food resources in the lake. Some feed on insect larvae, others zooplankton or algae. Some newly discovered fish are predators with large teeth, which we named 'large-tooth serranchromines'."

Many people assume fish are all the same species because they all live in water. But there are 30,000 different species of fish and many of them are markedly different from each other. Expecting them to mate outside of their own species is like expecting a horse to mate with a cat because they both have four legs and a tail.

Fossil records show fish have existed for more than 500 million years which makes them very old on the evolutionary scale. There are more than 1300 species of cichlids and many are popular aquarium fish. They are primarily freshwater fish and the majority of species are African, appearing in great diversity in the major African lakes where this 10-year study took place.

Female cichlid fish choose their partner and in mating ritual tests in the lab, the team of international scientists discovered that under certain circumstances the females would choose a male from different species that had similar colouring to males from their own species. They also found that when the light conditions are poor, the females could not distinguish between males of their own species or from other species because they could not see their colours properly.

This is what they determined happened a million years ago when the different species of fish mixed together when Lake Mweru was formed, sparking the evolution of 40 new species of fish.

Dr Meier explained: "To diversify into different species, the cichlid fish needed the ecological opportunity provided by the new habitats of Lake Mweru, formed one million years ago, which is still considered to be recent in evolutionary terms! That more than 40 species utilising different food resources and habitats could evolve so rapidly is highly unusual.

"When Lake Mweru was formed it combined cichlid lineages from the Congo and the Zambezi. The cichlids from these different drainage systems then mated with each other. This could have been because when the lake formed, the water was very cloudy and they couldn't see colours properly so the females were not being as choosy about selecting a mate in their new environment. Mating between cichlids from different drainage systems produced very diverse offspring combining the genetic traits of both parental species."

The so-called 'hybrid offspring' can feed on different things to their parents and invade new habitats - like swimming into deeper areas of the lake. It is unclear whether all of the species will survive as they may compete with each other and die out.

Dr Meier said: "Our research shows that hybridisation can fuel the evolution of new species which is a very novel finding. Hybridisation has traditionally been viewed as something bad because if species hybridise they can, over time, merge into a single species and you lose biodiversity or lose the local species. The melting pot of Lake Mweru gave us a rare opportunity to study interactions between evolving new species and showed that in a new environment with lots of ecological opportunity hybridisation can be a good thing that actually increases biodiversity."

Migraine headache is the third most common disease in the world affecting about 1 in 7 people. More prevalent than diabetes, epilepsy and asthma combined, migraine headaches are among the most common and potentially debilitating disorders encountered by primary health care providers. Migraines also are associated with an increased risk of stroke.

There are effective prescription medications available to treat acute migraine headaches as well as to prevent recurrent attacks. Nonetheless, in the United States many patients are not adequately treated for reasons that include limited access to health care providers and lack of health insurance or high co-pays, which make expensive medications of proven benefit unaffordable. The rates of uninsured or underinsured individuals have been estimated to be 8.5 percent nationwide and 13 percent in Florida. Furthermore, for all patients, the prescription drugs may be poorly tolerated or contraindicated.

Researchers from Florida Atlantic University's Schmidt College of Medicine have proposed aspirin as a possible option for consideration by primary care providers who treat the majority of patients with migraine. Their review includes evidence from 13 randomized trials of the treatment of migraine in 4,222 patients and tens of thousands of patients in prevention of recurrent attacks.

Their findings, published in The American Journal of Medicine, suggest that high-dose aspirin, in doses from 900 to 1,300 milligrams given at the onset of symptoms, is an effective and safe treatment option for acute migraine headaches. In addition, some but not all randomized trials suggest the possibility that daily aspirin in doses from 81 to 325 milligrams may be an effective and safe treatment option for the prevention of recurrent migraine headaches.

"Our review supports the use of high dose aspirin to treat acute migraine as well as low dose daily aspirin to prevent recurrent attacks," said Charles H. Hennekens, M.D., Dr.PH, corresponding author, first Sir Richard Doll Professor and senior academic advisor in FAU's Schmidt College of Medicine. "Moreover, the relatively favorable side effect profile of aspirin and extremely low costs compared with other prescription drug therapies may provide additional clinical options for primary health care providers treating acute as well as recurrent migraine headaches."

Common symptoms of migraine include a headache that often begins as a dull pain and then grows into a throbbing pain, which can be incapacitating and often occurs with nausea and vomiting, and sensitivity to sound, light and smell. Migraines can last anywhere from four to 72 hours and may occur as many times as several times a week to only once a year.

"Migraine headaches are among the most common and potentially debilitating disorders encountered by primary health care providers," said Bianca Biglione, first author and a second-year medical student in FAU's Schmidt College of Medicine. "In fact, about 1 in 10 primary care patients present with headache and three out of four are migraines. Aspirin is readily available without a prescription, is inexpensive, and based on our review, was shown to be effective in many migraine patients when compared with alternative more expensive therapies."

Approximately 36 million Americans suffer from migraine headaches and the cause of this disabling disorder is not well understood. There is a higher prevalence in women (18 percent) than men (9 percent). In women, the prevalence is highest during childbearing age.

Approximately 90 percent of migraine sufferers report moderate to severe pain, with more than 50 percent reporting severe impairment or the need for bed rest as well as reduced work or school productivity.

The United Nations Climate Change (COP25) World Climate Summit, which starts today in Madrid, is the latest initiative by world governments to seek agreement on legal frameworks to help protect the planet. However, there are still many critical voices that question the effectiveness of laws in reducing pollution. Opponents of regulation claim that laws can lead to systems that are too rigid and unable to adapt to technological changes. Others believe that firms will find ways to bypass legal controls and that, therefore, laws do not achieve significant progress. However, this review of research on the subject points to a scenario that is, in fact, much more favourable toward the potential of environmental regulation.

A team of three researchers coordinated by Alberto Aragón, Professor of Business Management at the University of Granada, conducted a painstaking review of the primary empirical research findings on environmental regulation and business management. The study aimed to offer recommendations based on points of consensus.

The work was conducted in collaboration with Professor Alfred Marcus (University of Minnesota) and Professor David Vogel (University of Berkeley) and is due for publication in Academy of Management Annals--the number one research journal in the world by impact factor in the categories of "business" and "management".

The work conducted by Aragón, Marcus, and Vogel reviewed in depth the results of some 70 studies published in the leading academic journals in the world. The samples of the studies reviewed, taken as a whole, included some 97,000 observations made by firms subject to different environmental regulations. The studies considered firms and regulations from many different countries, focusing in particular on the United States but also including firms based in Canada, China, Taiwan, Australia, Costa Rica, the European Union, and India, among others. The conclusions of the present study distinguish between the effects of compulsory and voluntary environmental regulatory pressure.

Compulsory laws are the most widely known, and the studies indicated that these exerted a stronger effect on reducing pollution among the firms in question than any other factor analysed--even greater than the pressures exerted by customers. Furthermore, the researchers identified differences between the effects attributed to the investigations that oblige firms to use certain technologies to achieve compliance and those that oblige them to achieve certain objectives or outcomes.

Technology-centric performance standards can be more problematic in competitive terms, because fixed systems can become outdated or run the risk of not being well-suited to the particular conditions of many firms. However, those that are based on setting objectives enable each firm to decide on the most appropriate procedures at all times and encourage them to continuously improve if the objective is linked to that of the best performers.

Although such outcome-based regulations were found to be markedly more effective, all compulsory environmental regulations exert tremendous power among firms to reduce pollution. At the same time, the studies found no substantial, generalised drop in profitability or competitiveness among firms as a result of their implementation of these regulations. Many firms even become more competitive as a result of the technological improvements associated with their efforts to comply with the mandatory standards. Furthermore, the option of self-regulation was designed precisely to facilitate even greater flexibility for firms.

Although voluntary environmental regulation has proved to be a very popular development in recent years, its results in terms of the impulse to reduce environmental impact have been modest.

Self-regulation means the company is free to comply with the standard in question, or not. The ISO 14000 systems or the EMAS system proposed by the European Union are among the best-known voluntary environmental regulations. In the region of 400,000 companies in the world have voluntarily obtained an ISO14001 certificate to show their compliance via an environmental management system in their facilities.

Weak compliance control

The research conducted on this type of standard reveals two worrying factors. First, compliance control is typically weak, which undermines the credibility of the system. Second, many firms focus on the administrative requirements to achieve certification, falling into the trap of "symbolic compliance". All of the studies, however, highlight that voluntary regulations present characteristics that make them potentially interesting, providing certain conditions are fulfilled in their design.

Having reviewed in detail the scholarship dealing with this subject, Aragón, Marcus, and Vogel propose a series of recommendations for future regulations, highlighting the importance of three fundamental aspects. First, governments and organisations that promote voluntary regulations should be concerned not only with the regulation itself, but also with its monitoring, to ensure its effectiveness. Second, the regulations should simultaneously seek to include both voluntary and compulsory elements, in a bid to combine the flexibility and effectiveness that characterizes each type.

Finally, the study recognises that differences in regulatory requirements around the world generate temptations for many firms and governments, which believe that, by reducing their environmental efforts, they can secure economic advantages.

In that regard, international regulations that are agreed by the countries known to be the heaviest polluters would be a fundamental step toward achieving important future progress. The researchers look optimistically to events such as the World Climate Summit, while recognising that only very limited internationally-coordinated regulatory advances have been achieved to date.

The eyes of the extinct sea scorpion Jaekelopterus rhenaniae have the same structure as the eyes of modern horseshoe crabs (Limulidae). The compound eyes of the giant predator exhibited lens cylinders and concentrically organized sensory cells enclosing the end of a highly specialized cell. This is the result of research Dr Brigitte Schoenemann, professor of zoology at the Institute of Biology Didactics at the University of Cologne, conducted with an electron microscope. Cooperation partners in the project were Dr Markus Poschmann from the Directorate General of Cultural Heritage RLP, Directorate of Regional Archaeology/Earth History and Professor Euan N.K. Clarkson from the University of Edinburgh. The results of the study 'Insights into the 400 million-year-old eyes of giant sea scorpions (eurypterida) suggest the structure of Palaeozoic compound eyes' have been published in the journal Scientific Reports - Nature.

The eyes of modern horseshoe crabs consist of compounds, so-called ommatidia. Unlike, for example, insects that have compound eyes with a simple lens, the ommatidia of horseshoe crabs are equipped with a lens cylinder that continuously refracts light and transmits it to the sensory cells.

These sensory cells are grouped in the form of a rosette around a central light conductor, the rhabdom, which is part of the sensory cells and converts light signals into nerve signals to transmit them to the central nervous system. At the centre of this 'light transmitter' in horseshoe crabs is a highly specialized cell end, which can connect the signals of neighbouring compounds in such a way that the crab perceives contours more clearly. This can be particularly useful in conditions of low visibility under water. In the cross-section of the ommatidium, it is possible to identify the end of this specialized cell as a bright point in the centre of the rhabdom.

Brigitte Schoenemann used electron microscopes to examine fossil Jaekelopterus rhenaniae specimens to find out whether the compound eyes of the giant scorpion and the related horseshoe crabs are similar or whether they are more similar to insect or crustacean eyes. She found the same structures as in horseshoe crabs. Lens cylinders, sensory cells and even the highly specialized cells were clearly discernible.

'This bright spot belongs to a special cell that only occurs in horseshoe crabs today, but apparently already existed in eurypterida,' explained Schoenemann. 'The structures of the systems are identical. It follows that very probably this sort of contrast enhancement already evolved more than 400 million years ago,' she added. Jaekelopterus most likely hunted placoderm. Here, its visual apparatus was clearly an advantage in the murky seawater.

Sea scorpions, which first appeared 470 million years ago, died out about 250 million years ago, at the end of the Permian age - along with about 95 percent of all marine life. Some specimens were large oceanic predators, such as Jaekelopterus rhenaniae. It reached a length of 2.5 meters and belonged to the family of eurypterida, the extinct relatives of the horseshoe crab. Eurypterida are arthropods, which belong to the subphylum Chelicerata, and are therefore related to spiders and scorpions.

Among the arthropods there are two large groups: mandibulates (crustaceans, insects, trilobites) and chelicerates (arachnid animals such as sea scorpions). In recent years, Schoenemann has been able to clarify the eye structures of various trilobite species and to make decisive contributions to research into the evolution of the compound eye. 'Until recently, scientists thought that soft tissues do not fossilize. Hence these parts of specimens were not examined until not so long ago', she concluded.

The new findings on the eye of the sea scorpion are important for the evolution of the compound eyes not only of chelicerates, but also for determining the position of sea scorpions in the pedigree of these animals and for the comparison with the eyes of the related group of mandibulates.

How the languages of the world emerged is largely a mystery. Considering that it might have taken millennia, it is intriguing to see how deaf people can create novel sign languages spontaneously. Observations have shown that when deaf strangers are brought together in a community, they come up with their own sign language in a considerably short amount of time. The most famous example of this is Nicaraguan Sign Language, which emerged in the 1980s. Interestingly, children played an important role in the development of these novel languages. However, how exactly this happened has not been documented, as Manuel Bohn describes: "We know relatively little about how social interaction becomes language. This is where our new study comes in."

In a series of studies, researchers at the Leipzig Research Centre for Early Childhood Development and the Max Planck Institute for Evolutionary Anthropology attempted to recreate exactly this process. The idea had been around for quite some time, says Gregor Kachel. But there was a problem: how to make children communicate with each other without them reverting to talking to each other? The solution came up in Skype conversations between the two researchers from Germany and their colleague Michael Tomasello in the US. In the study, children were invited to stay in two different rooms and a Skype connection was established between them. After a brief familiarization with the set-up, the researchers sneakily turned off the sound and watched as the children found new ways of communicating that go beyond spoken language.

The children's task was to describe an image with different motifs in a coordination game. With concrete things - like a hammer or a fork - children quickly found a solution by imitating the corresponding action (e.g. eating) in a gesture. But the researchers repeatedly challenged the children with new, more abstract pictures. For example, they introduced a white sheet of paper as a picture. The depicted "nothing" is difficult to imitate. Kachel describes how two children nevertheless mastered this task: "The sender first tried all sorts of different gestures, but her partner let her know that she did not know what was meant. Suddenly our sender pulled her T-shirt to the side and pointed to a white dot on her coloured T-shirt. The two had a real breakthrough: of course! White! Like the white paper! Later, when the roles were switched, the recipient didn't have a white spot on her T-shirt, but she nevertheless took the same approach: she pulled her T-shirt to the side and pointed to it. Immediately her partner knew what to do." Within a very short time, the two had established a sign for an abstract concept. In the course of the study, the images to be depicted became more and more complex, which was also reflected in the gestures that the children produced. In order to communicate, for example, an interaction between two animals, children invented separate gestures for actors and actions and began to combine them - thus creating a kind of small local grammar.

How does a language emerge? Based on the present study, the following steps appear plausible: first, people create reference to actions and objects via signs that resemble things. The prerequisite for this is a common ground of experience between interaction partners. Partners also coordinate by imitating each other such that they use the same signs for the same things. The signs thus gain interpersonal and eventually conventional meaning. Over time, the relationships between the signs and things become more abstract and the meaning of the individual signs more specific. Grammatical structures are gradually introduced when there is a need to communicate more complex facts. However, the most remarkable aspect of the current studies is that these processes can be observed under controlled circumstances and within 30 minutes.

The studies demonstrate that communication cannot be reduced to words alone. When there is no way to use conventional spoken language, people find other ways to get their message across. This phenomenon forms the basis for the development of new languages. The study by Manuel Bohn, Gregor Kachel and Michael Tomasello shows what the first steps in the development of a new language could look like. According to Bohn, however, numerous new questions arise at this point: "It would be very interesting to see how the newly invented communication systems change over time, for example when they are passed on to new 'generations' of users. There is evidence that language becomes more systematic when passed on."

The properties of 2D transition metal dichalcogenides are attracting a great deal of interest, and one of the reasons is their catalytic activity. In particular, better catalysts are needed to exploit the potential of water electrolysis - splitting water into its component elements - to provide sustainable energy storage.

"MoS2 is one of the most promising precious rare metal-free catalysts for the hydrogen evolution reaction (HER)," point out Yasufumi Takahashi, Mingwei Chen, and Tomokazu Matsue and their colleagues at Kanazawa University and other collaborating institutions in Japan, the US and the UK in their recent Angewandte Chemie International Edition report. The work highlights the role of "scanning electrochemical cell microscopy" for engineering the catalytic properties of these 2D materials.

As the researchers point out, scanning electrochemical microscopy has already proved useful in investigations of the catalytic activity of MoS2 monolayers, which have focused on the effects of strain, as well as the metallic versus semiconducting properties of different microstructural phases of MoS2 on HER catalysis. These studies used a microscale electrode to probe the sample for electrochemical activity as a function of location with high spatial resolution, on account of the microscale dimensions of the electrode.

In their scanning electrochemical cell microscopy studies, Takahashi, Chen, Matsue and colleagues use a nanopipette as a local, moveable electrochemical cell to probe the electrochemical activity on the surface instead of an ultramicroelectrode. They highlight the "reproducible and reliable technique for fabricating nanoprobes together with fast electrochemical characterization due to its small capacitive current" as additional advantages of this form of the characterization technique.

The researchers used a nanopipette with a 20 nm radius to study triangular monolayers of MoS2 with a 1H microstructural phase, as well as heterostructures of MoS2 and WS2. Each flake had a side length of around 130 nm. The measurements revealed changes in catalytic activity where edges, terrace features and heterojunctions between MoS2 and WS2 were located, which agrees with the suggestions of previous reports. In addition, aging the sample had a noticeable effect, particularly at edges.

The researchers conclude that their study demonstrates how it is possible to evaluate the local HER activity of catalytic samples using scanning electrochemical cell microscopy. They suggest that the technique can be a "powerful tool" for engineering the phase and structure of 2D transition metal dichalcogenide samples for applications in catalysis.

[Background]

2D transition metal dichalcogenides

The isolation of graphene and the extraordinary properties identified in the material attracted intense interest from researchers not only in graphene but in a whole host of other materials, where 2D layers could be isolated. Among these 2D materials are transition metal dichalcogenides where the transition metals include molybdenum (Mo) and tungsten (W) and the chalcogens are group VI elements, which include sulfur (S), selenium (Se) and tellurium (Te). As well as electrochemical catalysis for energy storage, this group of materials has also attracted interest for high-end electronics, spintronics, optoelectronics, energy harvesting, flexible electronics, DNA sequencing and personalized medicine.

The hydrogen evolution reaction

The use of hydrogen as a fuel involves burning it in oxygen to produce just water and the release of a lot of energy. Hydrogen fuel avoids the use of fossil fuels and the production of carbon dioxide, and it can get around some of the issues of energy storage associated with many alternative sustainable energy technologies such as solar and wind power. The electrolysis of water using a sustainably sourced current provides an environmentally friendly way of producing hydrogen fuel. Although HER is faster than the oxygen evolution reaction, there is still great interest in increasing the reaction rates. As a result, there is a lot of interest in the catalytic activity of 2D transition metal dichalcogenides on HER among other reactions.

A research team headed by Prof. Dr. Sebastian Arnold and Jelena Tosic from the Faculty of Medicine at the University of Freiburg has now succeeded in deciphering basic molecular control mechanisms by which stem cells decide which embryonic cell types to turn into.
This is achieved at least partially through selective usage of the genes for each different cell type, despite the presence of the identical genetic information in every cell in the body.

The scientists have published their findings in the journal Nature Cell Biology.

The undifferentiated stem cells of the embryo develop either into cells of the nervous system, the so-called neuroectoderm, or into cells of the meso- and endoderm, from which, for example, many different cell types of the internal organs or the muscles develop. For over 25 years it has been known that this decision is regulated by embryonic signaling molecules, such as TGFβ and Wnt signals. So far, however, it has remained unclear exactly how these signals control this first decision of cell differentiation. The study, carried out in the context of Tosic's doctoral thesis, shows that the embryonic TGFβ and Wnt signals are transmitted by gene-regulating transcription factors of the T-box factor family, namely Eomes and Brachyury. These factors are responsible for "turning on" the differentiation gene programs for all meso- and endoderm cells. At the same time, these T-box factors also act as gene repressors, preventing the formation of neural tissue by suppressing the corresponding gene programs. This involves changes in the structure but not the content of the genetic information in the cell nucleus.

"The results of the study represent a crucial step towards understanding the basic mechanisms of how cells develop their future identity during development," says Arnold. They also allow further studies on how cell identity is permanently encoded in a cell.

The amount of carbon transported via Finnish rivers to the Baltic Sea has risen substantially in the past few decades. This was found in a collaborative study by the University of Helsinki, Aarhus University and the Finnish Environment Institute. The researchers don't know the exact effects yet.

The researchers investigated changes in the amount of organic carbon by exploring water-quality monitoring data for 30 rivers and a period of 25 years. The data demonstrated that Finnish rivers now transport 280,000 tonnes more carbon to the Baltic Sea each year than they did in the early 1990s.

Previous studies have shown that the riverine total organic carbon (TOC) load to the Baltic Sea is closely connected to precipitation: the load in a dry year may be less than half of that in a rainy year. Considerable year-on-year variation has hindered the observation of long-term trends, but the dataset collected in recent decades with modern measuring techniques is now sufficiently extensive for reliable assessments.

"We found that TOC concentrations have increased in almost every river since the early 1990s. When combined with discharges that have remained unchanged or increased, TOC discharge to the Baltic Sea has increased considerably: by almost 50% from 1993," explains Eero Asmala, a postdoctoral researcher at the Faculty of Biological and Environmental Sciences, University of Helsinki.

The phenomenon can be attributed, in particular, to climate change and the associated increases in precipitation and temperature. The researchers discovered that the rise in TOC concentrations can be explained in half of the cases by changes in discharge, which has been caused, in turn, by changes in precipitation. In addition, increasing temperatures and decreasing acidity contributed to an increase in TOC concentrations observed in some areas. Land use also affected the growth of TOC concentrations.

"The larger the share of a catchment drained, the more TOC concentrations had increased. The rise in concentrations was approximately 20% in the least drained catchments, whereas it was twice as large in the most drained catchments," notes Antti Räike, senior researcher at the Finnish Environment Institute.

The rising TOC concentrations and discharges of Finnish rivers have coincided with the decreasing TOC contents in Finnish soil. It is possible that at least some of the carbon that has disappeared from the soil has been transported by rivers to the Baltic Sea.

The increasing TOC concentration makes waters turbid and decreases water transparency. In addition, the increased organic load increases the risk of hypoxia in bottom waters.

"On balance, we still do not know much about how the carbon that ends up in the Baltic Sea affects the coastal ecosystem," Asmala says.

However, several research projects at the University of Helsinki are currently exploring the climate effects of, in particular, carbon transported to coastal waters.