Culture

The respiratory systems of Atlantic salmon function normally even when carrying large loads of piscine orthoreovirus (PRV), new UBC research has found.

"We didn't find significant harm to the fish's respiratory physiology despite the virus replicating to a load equal to, if not higher, than those seen naturally in wild or farmed fish" said Yangfan Zhang, a PhD student in UBC's faculty of land and food systems and lead author of the study published today in Frontiers in Physiology.

PRV is present in nearly all farmed Atlantic salmon on Canada's west coast, and various strains of PRV have been detected in many salmonid species around the world. Consequently, the results are a positive step in reducing the uncertainty about the potential of infected farmed Atlantic salmon in marine pens to negatively impact migrating wild Pacific salmon.

PRV replicates in the red blood cells that carry oxygen throughout salmon's bodies, and is sometimes associated with cardiac inflammation. If a PRV infection were to compromise salmon's respiratory fitness, fish could have trouble reaching their spawning grounds, a consequence that could be dire for a declining salmon population.

The researchers performed their 21-week experiment on groups of juvenile Atlantic salmon obtained from a commercial hatchery on Vancouver Island and recently transferred to seawater. One group was injected with a dose of PRV that was high enough to represent a worst-case infection scenario.

The scientists used respirometry--not unlike the VO2 max test undertaken by elite athletes--to measure how efficiently oxygen was taken up and transported by the salmon's cardiorespiratory system. They also measured 13 other indicators, such as the fishes' ability to recover from exertion, whether they were settled or active in the testing chamber, and their ability to perform anaerobic tasks.

They found no physiological differences between the infected fish and fish from a control group, a result that highlights the distinction between a virus being prevalent and being virulent. Prevalence refers to how widespread a virus is among a population; virulence refers to the damage it causes. While most people equate viral infection with disease, in the case of the B.C.-farmed Atlantic salmon, one did not necessarily lead to the other.

"Besides no sublethal effects of a 'full-on' PRV infection, none of our fish died and none developed severe inflammation of the heart. These data show that there is minimal risk of ensuing problems from the B.C. strain of PRV to B.C. farmed Atlantic salmon," said Tony Farrell, a professor in UBC's faculty of land and food systems and a principal investigator of the research team.

The authors have performed a similar experiment on wild sockeye salmon with similar results, which they are now compiling for publication.

The UBC researchers worked with scientists from Fisheries and Oceans Canada, which funded the study.

Democratic governance is linked with declines in cardiovascular disease mortality and road deaths, as well as increases in government health spending

Life expectancy improved faster in countries that transitioned to democracy between 1970 and 2015 compared to those that did not--increasing by an average of 3% after 10 years

Democracy appears to play a bigger part in health outcomes than a country's GDP--accounting for about 25% of the reductions in deaths from cardiovascular disease and transport injuries over time

Increasing funding for development agency-led programmes promoting open and accountable democratic institutions and processes may help improve health and increase investment in high-quality, accessible healthcare

Democratic rule, enforced by regular free and fair elections, appears to make an important contribution to adult health by increasing government spending on health and potentially reducing deaths from several non-communicable diseases (NCDs) and transport injuries. Conversely, autocracies that escape this general scrutiny, and do not have the same external pressures or support from global health donors to tackle NCDs and injuries, may have less incentive to finance their prevention and treatment, and seem to underperform as a result.

The findings are from the first comprehensive assessment of the impact of democracy on adult health and cause-specific mortality using detailed political, economic, and population health information for 170 countries over the past 46 years (1970-2016), published in The Lancet.

"The results of this study suggest that elections and the health of the people are increasingly inseparable," says Thomas Bollyky from the Council on Foreign Relations, USA, who led the research. "Without the same pressure or validation from voters or foreign aid agencies, autocratic leaders have less incentive than their democratic counterparts to finance the more expensive prevention and treatment of heart diseases, cancers, and other chronic illnesses. Despite being responsible for an estimated 58% of the death and disability in low- and middle-income countries, just 2% of development assistance for health was devoted to non-communicable diseases in 2016." [1]

The findings suggest that average adult life expectancy (after controlling for HIV/AIDS [2]) improved faster in countries that transitioned to democracy between 1970 and 2015 compared to those that did not transition--increasing by an average of 3% after 10 years (figure 1). Moreover, as levels of democracy increased, governments spent more on health, irrespective of a country's economic wellbeing (gross domestic product [GDP] per capita).

The causes of mortality that appear to be most affected by democratic experience--cardiovascular diseases, tuberculosis, transport injuries, and several other non-communicable diseases--are responsible for over a quarter of all the death and disability in individuals aged 70 years and younger in low- and middle-income countries.

"Our estimates represent a potentially major change in how we think about tackling global health challenges", says co-author Dr Joseph Dieleman from the Institute for Health Metrics and Evaluation, USA. "In a time of stagnant aid budgets, and as the burden of disease rapidly shifts to non-communicable diseases, international health agencies and donors may increasingly need to consider the implications of regime type in order to maximise health gains." [1]

"Efforts to improve the health of adults might benefit from funding programmes that help countries to strengthen their democratic processes and build more accountable institutions. So would directing more of the scarce development assistance for health to causes where democratic performance has the most effect on health, such as cardiovascular diseases." [1]

The past decade has seen falling levels of democracy around the world, with an estimated 2.5 billion people--a third of the world's population--living in countries where democratic qualities (e.g., freedom of expression, the right to vote, and freedom of association) are in decline [3].

The extent to which a country's democratic experience impacts population health has been poorly understood. So far, studies have focused on broad measures of child and infant health (e.g., mortality rates and life expectancy) that have reported conflicting findings, and have been unable to conclude whether the democratic process itself is affecting health, or if other factors such as country income, or the quality of government institutions, might be responsible.

To explore this further, the authors analysed political, economic, and population health data from the Global Burden of Disease study, the University of Gothenburg's Varieties of Democracy project, and Financing Global Health database [4]. They modelled the effect of democracy on cause-specific mortality, HIV-free life expectancy at age 15 years, and health spending in 170 countries.

Given that democratic and autocratic countries alike received substantial amounts of international aid for HIV/AIDS, the authors controlled for HIV in the analysis of life expectancy at age 15 to better isolate and assess the effect of regime type on adult health between 1970 and 2015. The researchers also investigated the pathways by which democratic rule might improve health [5].

Results indicate that democratic experience accounted for more of the reduction in mortality within a country than GDP for cardiovascular diseases (22% vs 12%), transport injuries (18% vs 7%), cancers (10% vs 6%), cirrhosis (6% vs 2%), and other non-communicable diseases such as congenital heart disease and congenital birth defects (13% vs 9%) between 1995 and 2015 (figure 2). In contrast, democracy explained little of the declines in mortality for some of the leading communicable causes of death such as HIV (3%) and malaria (4%), which are more heavily targeted by international aid.

Democracy also did not appear to have substantial effects on mortality from all NCDs. Democratic experience appears to be important for causes dependent on good quality care, but accounts for less than 1% of the changes in mortality from diabetes, which is largely driven by non-utilisation of health-care services. The low number of deaths from mental health and musculoskeletal disorders globally make the study's results on these causes hard to analyse.

The researchers also estimated that the average country's increase in democratic experience (via direct and indirect effects such as increased government spending and economic growth) reduced deaths from cardiovascular disease and other NCDs by around 9%, and tuberculosis by roughly 8% between 1995 and 2015 (figure 4).

The authors acknowledge that many global health practitioners may be concerned that the more political global health assistance becomes, the more it could undermine productive relationships with local governments. They say: "This reticence about democracy promotion is understandable, but it ignores the inevitably political nature of many current global health objectives...Ignoring the role of civil society, a free media, and open and accountable government in resolving these debates undermines efforts to build institutional capacity and the popular support needed for sustained population health improvements. Pretending otherwise is akin to believing that the solution to a nation's crumbling roads and infrastructure is just a technical schematic and cheaper materials."

The authors note that the link between democracy and population health is difficult to measure because of the association of democracy with other factors, such as country income or total health expenditure. The authors used multiple statistical measures to reduce the risk of confounders, but they remain impossible to rule out. They also point out that the factors in the analysis together explained less than three-quarters of the total reductions in mortality for some causes, so there may be other factors that might play important roles, which they were unable to identify. Lastly, they note that whilst GBD 2016 provides the only comprehensive data on cause-specific mortality in all countries, it relies on modelling estimates that may be affected by a lack of data in low-income countries, particularly for causes like cardiovascular diseases and other NCDs.

Commenting on the implications of the findings in a linked Comment, Dr Helen Epstein from Bard College, USA, writes: "Global health advocacy groups need to do more than clamour for more funding and occasionally bemoan corruption. They need to call on Washington (USA), Brussels (Belgium), and London (UK), to impose sanctions on dictators, including those who cooperate with western military aims."

The blood test used to diagnose a heart attack (acute myocardial infarction) in patients admitted to hospital can be misleading, warn researchers in a study published by The BMJ today.

Of 20,000 consecutive patients undergoing blood tests at University Hospital Southampton, one in 20 had levels of troponin (a protein released into the bloodstream during a heart attack) greater than the manufacturer's recommended upper limit. But in most of these patients were being seen for other conditions and so there were no clinical signs or symptoms of a heart attack.

Troponin levels also differed according to several factors such as age, sex and whether inpatient or outpatient.

The researchers, led by cardiologist Professor Nick Curzen, say these results highlight the need for medical staff to interpret troponin levels carefully in order to avoid misdiagnosis of a heart attack and inappropriate treatment.

Current guidelines recommend troponin tests to help exclude or diagnose a heart attack. Manufacturers of troponin tests provide a recommended level (known as the 99th centile) based on values from a few hundred healthy individuals.

This recommended level is used as the upper limit of normal (ULN). In other words, if the value of troponin is above the 99th percentile, that is considered to be abnormal, and would indicate a heart attack in appropriate clinical circumstances.

But little is known about the true distribution of the troponin level across a whole hospital population that includes inpatients, outpatients, patients undergoing surgery, in intensive care etc.

So researchers measured levels of high sensitivity cardiac troponin I (hs-cTnI) in 20,000 inpatients and outpatients undergoing blood tests for any reason at University Hospital Southampton between 29 June and 24 August 2017.

The average age of participants was 61 and 53% (10,580) were women.

The researchers found that the 99th centile of troponin for the whole study population was 296 ng/L compared with the manufacturer's recommended level of 40 ng/L.

One in 20 (1,080; 5.4%) of all 20,000 patients had a troponin level greater than 40 ng/L, but in most of these patients there was no clinical suspicion of a heart attack.

Overall, 39% of all patients from the critical care units, 14% of all medical inpatients, and 6% of all patients from the emergency department had a troponin concentration greater than the recommended ULN.

This is an observational study, and as such, can't establish cause, and the researchers point to some limitations, such as relying on patient records for details about management and diagnoses, and being unable to examine clinical outcomes.

Nevertheless, they say this study shows that "the 99th centile of high sensitivity troponin I concentration of the population in our hospital was substantially higher than the manufacturer's recommended ULN used in clinical practice based on the 99th centile for a healthy population."

These data "highlight the need for clinical staff to interpret hs-cTnI concentrations carefully, particularly when applying the recommended ULN to diagnose acute myocardial infarction, in order to avoid misdiagnosis in the absence of an appropriate clinical presentation," they conclude.

Academics led by Professor Lucie Cluver at Oxford University have shown how key services in lower and middle-income countries can contribute to multiple sustainable development goals (SDGs), even for the highest-risk children and adolescents.

The study, led by Oxford University in collaboration with the universities of Cape Town and Witwatersrand, University College London and the United Nations Development Programme (UNDP), is the first to test the UN's concept of 'accelerators': provisions that can improve the lives of vulnerable populations in not only one SDG area, but many. It finds clear evidence for these, even among an exceptionally high-risk group, adolescents living with HIV in South Africa. It goes further to find that simple combinations of accelerators - such as parenting support, cash transfers and safe schools - provide even greater impacts.

Professor Cluver, Professor of Child and Family Social Work in Oxford's Department of Social Policy and Intervention, said: 'This new evidence is a step forward in reaching the Sustainable Development Goals. Even for one of Africa's most vulnerable groups - adolescents living with HIV and AIDS - the right combinations of programmes can help. By providing social welfare grants, safe schools and supportive parenting for these highest-risk teens, we can make substantial positive impacts across health, education, gender equality and violence prevention. We are delighted to be working with UNDP, UNICEF and other agencies to use these new findings in their work with governments across Africa.'

Most studies that look at whether democracy improves global health rely on measurements of life expectancy at birth and infant mortality rates. Yet those measures disproportionately reflect progress on infectious diseases -- such as malaria, diarrheal illnesses and pneumonia -- which relies heavily on foreign aid.

A new study led by Stanford Medicine and the Council on Foreign Relations suggests that a better way to measure the role of democracy in public health is to examine the causes of adult mortality, such as noncommunicable diseases, HIV, cardiovascular disease and transportation injuries. Little international assistance targets these noncommunicable diseases.

When the researchers measured improvements in those particular areas of public health, the results proved dramatic.

"The results of this study suggest that elections and the health of the people are increasingly inseparable," the authors wrote.

A paper describing the findings will be published March 13 in The Lancet. Tara Templin, a graduate student in health research and policy at Stanford Health Policy, shares lead authorship with Thomas Bollyky, JD, director of the Global Health Program at the Council on Foreign Relations.

"Democratic institutions and processes, and particularly free and fair elections, can be an important catalyst for improving population health, with the largest health gains possible for cardiovascular and other noncommunicable diseases," the authors wrote.

Templin said the study brings new data to the question of how governance and health inform global health policy debates, particularly as global health funding stagnates.

"As more cases of cardiovascular diseases, diabetes and cancers occur in low- and middle-income countries, there will be a need for greater health care infrastructure and resources to provide chronic care that weren't as critical in providing childhood vaccines or acute care," Templin said.

Free and fair elections for better health

In 2016, the four mortality causes most ameliorated by democracy -- cardiovascular disease, tuberculosis, transportation injuries and other noncommunicable diseases -- were responsible for 25 percent of total death and disability in people younger than 70 in low- and middle-income countries. That same year, cardiovascular diseases accounted for 14 million deaths in those countries, 42 percent of which occurred in individuals younger than 70.

Over the past 20 years, the increase in democratic experience reduced mortality in these countries from cardiovascular disease, other noncommunicable diseases and tuberculosis between 8-10 percent, the authors wrote.

"Free and fair elections appear important for improving adult health and noncommunicable disease outcomes, most likely by increasing government accountability and responsiveness," the study said.

The researchers used data from the Global Burden of Diseases, Injuries and Risk Factors Study; V-Dem; and Financing Global Health databases. The data cover 170 countries from 1970 to 2015.

What Templin and her co-authors found was democracy was associated with better noncommunicable disease outcomes. They hypothesize that democracies may give higher priority to health care investments.

HIV-free life expectancy at age 15, for example, improved significantly -- on average by 3 percent every 10 years during the study period -- after countries transitioned to democracy. Democratic experience also explains significant improvements in mortality from cardiovascular disease, tuberculosis, transportation injuries, cancers, cirrhosis and other noncommunicable diseases, the study said.

And yet, this connection between fair elections and global health is little understood.

"Democratic government has not been a driving force in global health," the researchers wrote. "Many of the countries that have had the greatest improvements in life expectancy and child mortality over the past 15 years are electoral autocracies that achieved their health successes with the heavy contribution of foreign aid."

They note that Ethiopia, Myanmar, Rwanda and Uganda all extended their life expectancy by 10 years or more between 1996 and 2016. The governments of these countries were elected, however, in multiparty elections designed so the opposition could only lose, making them among the least democratic nations in the world.

Yet these nations were among the top two-dozen recipients of foreign assistance for health.

Only 2 percent of the total development assistance for health in 2016 was devoted to noncommunicable diseases, which was the cause of 58 percent of the death and disability in low-income and middle-income countries that same year, the researchers found.

"Although many bilateral aid agencies emphasize the importance of democratic governance in their policy statements," the authors wrote, "most studies of development assistance have found no correlation between foreign aid and democratic governance and, in some instance, a negative correlation."

Autocracies such as Cuba and China, known for providing good health care at low cost, have not always been as successful when their populations' health needs shifted to treating and preventing noncommunicable diseases. A 2017 assessment, for example, found that true life expectancy in China was lower than its expected life expectancy at birth from 1980 to 2000 and has only improved over the past decade with increased government health spending. In Cuba, the degree to which its observed life expectancy has exceeded expectations has decreased, from four-to-seven years higher than expected in 1970 to three-to-five years higher than expected in 2016.

"There is good reason to believe that the role that democracy plays in child health and infectious diseases may not be generalizable to the diseases that disproportionately affect adults," Bollyky said. Cardiovascular diseases, cancers and other noncommunicable diseases, according to Bollyky, are largely chronic, costlier to treat than most infectious diseases, and require more health care infrastructure and skilled medical personnel.

The researchers hypothesize that democracy improves population health because:

When enforced through regular, free and fair elections, democracies should have a greater incentive than autocracies to provide health-promoting resources and services to a larger proportion of the population.

Democracies are more open to feedback from a broader range of interest groups, more protective of media freedom and might be more willing to use that feedback to improve their public health programs.

Autocracies reduce political competition and access to information, which might deter constituent feedback and responsive governance.

Various studies have concluded that democratic rule is better for population health, but almost all of them have focused on infant and child mortality or life expectancy at birth.

Over the past 20 years, the average country's increase in democracy reduced mortality from cardiovascular disease by roughly 10 percent, the authors wrote. They estimate that more than 16 million cardiovascular deaths may have been averted due to an increase in democracy globally from 1995 to 2015. They also found improvements in other health burdens in the countries where democracy has taken hold: an 8.9 percent reduction in deaths from tuberculosis, a 9.5 percent drop in deaths from transportation injuries and a 9.1 percent mortality reduction in other noncommunicable disease, such as congenital heart disease and congenital birth defects.

"This study suggests that democratic governance and its promotion, along with other government accountability measures, might further enhance efforts to improve population health," the study said. "Pretending otherwise is akin to believing that the solution to a nation's crumbling roads and infrastructure is just a technical schematic and cheaper materials."

"A healthy community requires healthy soil." This idea spurred a consortium of researchers, farmers, and community garden practitioners to dive into the challenges--and opportunities--of urban agriculture. Their efforts, now in a second year, may highlight how urban soil can be a resource for human and environmental health.

"We can benefit from how we manage the environment," says researcher Jennifer Nicklay. "Clean water, clean air, and agriculture benefit us, our waterways, and wildlife. We put a value on crop yield, which is all well and good. But in urban ag, we're in such proximity to other humans. The other benefits become really important to think of as a whole."

Nicklay is a doctoral student at the University of Minnesota. Along with researchers at the University of St. Thomas and Hamline University, all located in the Minneapolis/St. Paul region, Nicklay is working with four urban growers to understand the contributions of city soils.

The growers have unique approaches to their urban plots. One group emphasizes community building and education, another culturally-relevant food. Another uses a community-supported agriculture model, while a final group emphasizes community reconciliation over yield.

For all groups, land permanence in the urban environment is a challenge. A lease may expire, a city code may prevent perennial plantings, or a tax burden prove unmanageable. "When you don't know how long you'll be there, it's hard to invest in long-term solutions," Nicklay says. "All the growers value land tenure and land access."

From the growers' perspective, "healthy soil" means it has enough organic matter and nutrients to encourage good plant growth. It's loose instead of compacted so water can move freely. From here, the concept of a "healthy community" moves upwards from the microbiome of helpful soil bacteria to insects, wildlife, and humans.

There's often more than just soil in the soil, from copper wires to chemical contamination. This challenges the growers. Researchers hope to also determine if they can leave the urban plots better than they found them.

The team is comparing the findings to another urban farm owned and monitored by the University of St. Thomas. They are also comparing the urban ag plots to urban green spaces such as parks. To do so, researchers gather soil and plant samples--some weekly, some less often--for 20 different lab tests. The results will provide information on urban ag's ecosystem services: changes to microbe and insect populations, water quality, soil fertility, and greenhouse gas emissions. Researchers also measure how much each urban plot will grow given different growing practices.

The two distinct growing experiences build on each other. "The University of St. Thomas farm allows us to scaffold the data. We can control more variables, see patterns and put them into context. In the less-controlled scenarios of our four urban growers we see the range of possibilities in the real world," Nicklay explains.

The team operates within a unique collaborative model. An annual "All Hands" meeting in the waning winter months unifies community and university participants with common goals. Weekly workdays and check-ins during the growing season maintain contact with grower sites to help share findings and address concerns. Community meetings and events throughout the year continue this close relationship.

"These regular, repeated interactions--in ways that are both related and not related to the project--are really, really important," Nicklay emphasizes. "It allows us to honor grower and community knowledge in all aspects of our work, from generating questions to designing methods to analyzing data."

Nicklay says the process is time-intensive but rewarding. "When something hasn't gone well, they tell me. We're able to work through it," she says. "We're getting so much from the farmers. We want to give back and answer community questions. We make sure people know we're here and invested in their success."

This research project will conclude in 2020. Researchers hope their findings will help urban growers and policymakers make better land use decisions.

"We need local, data-driven evaluation of these ecosystem services to complement our narratives and experiments in order to maximize land use strategies," Nicklay says.

"Already, we're thinking to the future. We know that there are innumerable community and home gardens in Minneapolis and St. Paul, and we want to figure out how to capture the impacts they are having. We can help researchers, growers, communities, and policymakers understand the potential impacts of urban agriculture at this larger scale."

New international guidelines on how to provide treatment for women having miscarriage surgery are needed after a large-scale international trial led by the University of Birmingham examined if antibiotics can avoid the surgical complication of a potentially fatal pelvic infection.

Published today (March 13th) in the New England Journal of Medicine (NEJM), the trial involved thousands of women at hospitals across four low and middle income countries and investigated whether giving a preventative single dose of inexpensive and widely available antibiotics to women prior to surgery reduces the risk of pelvic infection.

Sometimes not all of the pregnancy tissue contents of the womb come away on their own after a miscarriage. When this occurs, surgery may be required to remove it. Miscarriage surgery is one of the most common surgical procedures carried out around the world.

The results of the trial showed that giving antibiotics prior to miscarriage surgery did not result in a significant reduction in pelvic infection within 14 days post-surgery if clinical judgement was used to determine if there was an infection or not, however, when the strict international definition of pelvic infection was used then antibiotics were beneficial.

Before this study there was little information to guide practice, despite it being such a common procedure. Now practitioners and policy makers have high quality evidence.

It is particularly important to ensure that antibiotic prescribing is guided by the highest quality evidence to ensure we minimise unnecessary antibiotic use, which can fuel antibiotic resistance. International guidelines and practice should now be reassessed in light of this evidence.

The research, which was funded by MRC, Wellcome Trust, and UK Aid, was led by researchers at the Institute of Metabolism and Systems Research, the Institute of Applied Health Research, and the
Health Economics Unit at the University of Birmingham.

Just over 3,400 women were recruited to the randomized trial between June 2014 and April 2017 from 13 hospitals across Malawi, Tanzania, Uganda and Pakistan. All women who took part were scheduled for surgery after suffering a miscarriage when they were less than 22 weeks pregnant.

Two hours before surgery, half of the participants were given two antibiotics - doxycycline and metronidazole - while the other half were given a placebo. The results showed that when pelvic infection was defined by strict international criteria there was a 40 per cent reduction in infection in women who received antibiotics (infection rate was 1.5% and occurred in 26 out of 1,700 pregnancies), compared to those who did not receive any antibiotics (infection rate was 2.6% and occurred in 44 of 1,704 pregnancies). The rate of pelvic infection was 4.1% in the antibiotic group (68 out of of 1676 pregnancies), compared with 5.3% (90 out of 1684 pregnancies) in the placebo group if pelvic infection was defined pragmatically by clinicians.

Lead author Dr David Lissauer, of the University of Birmingham, said: "The question of whether to use antibiotics is particularly important in low and middle-income countries.

"Rates of surgery for miscarriage are high owing to low uptake of non-surgical management approaches, infections are more common following surgery in these countries versus higher resource countries, and access to resources to care for women who do develop complications is poor.

"Before the AIMS trial we had no idea what the right thing was to reduce the serious complication of pelvic infection.

"We finally now have the highest quality evidence that a single, cheap, preventative dose of two commonly available antibiotics was not only safe but also appeared to reduce pelvic infection if the infection was diagnosed using strict international criteria."

Arri Coomarasamy, Professor of Gynaecology at the University of Birmingham and Director of Tommy's National Centre for Miscarriage Research, added: "Prior to our study there has been little evidence to guide clinical practice, with previous trials evaluating antibiotic treatment pre-surgery in patients undergoing miscarriage surgery being limited by their size and quality.

"Through carrying out a study on such a large scale across multiple hospitals and countries we now have valuable evidence.

"We hope that this evidence will now be used to shape international guidelines and policy practice and will lead to improved treatment for women, potentially saving lives."

Concussion researchers have long suggested that damage to the corpus callosum, a thick bundle of nerves that connects the brain's two halves, could result in some common side effects of concussion, like dizziness or vision problems. The assumption is straightforward - that damage to the corpus callosum could affect coordination between the two halves - but difficult to prove.

Although still not proof, Stanford University researchers have gathered evidence to support the idea by combining data from sensors worn by athletes, simulations of brain movement based on those measurements and brain images of people with and without concussions. Their findings, published March 12 in Biomechanics and Modeling in Mechanobiology, suggest that impacts to the side of the head might cause harmful vibrations in a structure connected to the corpus collosum.

"Concussion is a big, vague term and we need to start breaking it down," said Fidel Hernandez, a former graduate student in the lab of David Camarillo, assistant professor of bioengineering at Stanford University, and co-lead author of the paper. "One way we can do that is to study individual structures that would be likely to cause traditional concussion symptoms if they were injured."

Evaluation, three ways

This research is built on data from mouth guards worn by football players and developed by the Camarillo lab. Each mouth guard records head movement and acceleration in six directions through an integrated accelerometer and gyroscope. Analyzing 115 impacts recorded by these mouth guards, the researchers found two associated with concussion diagnoses. By applying the mouth guard measurements to a simulation of the neck, head and brain, the researchers saw instances where the corpus callosum was pulled around by a structure above it called the falx.

The falx sits like a mohawk hairstyle between the brain's two halves and is stiffer than the rest of the brain, like leather versus gelatin. Watching reproductions of the recorded impacts and additional simulations, the researchers saw that hits to the side of the head could produce vibrations in the falx, due to its stiffness. Those could then propagate down to the corpus callosum, creating the kind of tissue strain that is often implicated in concussion. Simulated strikes that made the head tilt toward the shoulder produced C-shape waves in the falx, while those that caused the head to turn produced S-shaped waves.

With direction from the simulations, Michael Zeineh, assistant professor of radiology and his lab, including former postdoctoral fellow and co-lead author of the paper Maged Goubran, assessed magnetic resonance imaging (MRI) scans from the two athletes who had been diagnosed with concussion. The researchers looked with the most sensitive method available - diffusion imaging - and found evidence of possible damage to the corpus callosum in both brains.

Diffusion imaging is rarely used in clinical practice and, even with this advanced technology, the researchers only saw the corpus callosum abnormalities because they knew where to look and had a comparison group - scans from athletes from the same sport and with similar years of experience who had never been diagnosed with concussion.

"The bottom line is, when we do post-concussion brain scans in clinical settings, we don't find anything. I'd say 95 percent of them are normal," said Zeineh, who is also co-senior author of the paper. "Clinically, we interpret by eye, but the kinds of changes we're showing in the paper, you can't see with your eye. Concussion cannot be diagnosed by imaging alone."

Given there were only two concussions in the data, the researchers emphasize the connection between side impacts, corpus callosum strain by the falx and concussion is still a hypothesis. A few previous studies have discounted this link but none have combined biometric measurements, simulations and neuroimaging at this resolution. The researchers need more data to see how their hypothesis holds up and they are already working with women's lacrosse and additional football players to obtain that.

"The neuroimaging is really important for confirming the simulated models, but it's been difficult to get this combination of mouth guards and imaging," said Camarillo, who is co-senior author of the paper. "Now, we can prove these things out in a more rigorous and larger sample size."

Understanding what we're up against

When someone is diagnosed with a concussion, the treatment is almost always the same. The problem is that there are likely many kinds of concussions with symptoms that depend on which part of the brain was injured and how badly.

"All concussions are not created equal," said Hernandez. "We try to draw a line - a binary 'yes concussion' or 'no' - but concussions happen on a gradient."

A more detailed understanding of concussions could lead to more tailored treatments and change how we prevent them, showing us, for example, which kinds of concussions are most damaging or easiest to avoid. This topic matters beyond sports, as many concussions are the consequence of falls, particularly in the elderly or very young. Car crashes carry concussion risk as well. So, not only could research like this help improve protective gear for football players and cyclists, it could inform safety standards for cars or suggest new ways to design safer homes.

PITTSBURGH, March 12, 2019 - Lung cancer is the leading cause of cancer deaths worldwide. Screening is key for early detection and increased survival, but the current method has a 96 percent false positive rate. Using machine learning, researchers at the University of Pittsburgh and UPMC Hillman Cancer Center have found a way to substantially reduce false positives without missing a single case of cancer.

The study was published today in the journal Thorax. This is the first time artificial intelligence has been applied to the question of sorting out benign from cancerous nodules in lung cancer screening.

"We were able to rule out cancer in about a third of patients, so they wouldn't need biopsies, they wouldn't need PET scans or a short-interval CT scan. They just need to come back in a year," said senior author David Wilson, M.D., M.P.H., associate professor of medicine, cardiothoracic surgery and clinical and translational science at Pitt and co-director of the Lung Cancer Center at UPMC Hillman.

A low-dose CT scan is the standard diagnostic test for lung cancer for those at high risk. Nationwide, about a quarter of these scans turn up shadows indicating nodules in the lung - a positive result - but fewer than 4 percent of those patients actually have cancer.

Right now, it's impossible to know from the scan alone who those 4 percent are, Wilson said. Of course, physicians don't want to miss any real cases of cancer, but they're also trying to reduce the false positive rate, he noted.

"A positive test creates anxiety, increases health care costs, and the follow-up tests are not risk free," said study coauthor Panayiotis (Takis) Benos, Ph.D., professor and vice chair of computational and systems biology and associate director of the Integrative Systems Biology Program at Pitt. "For the 96 percent of people who have benign nodules, these procedures are unnecessary. So, we try to mine the data to tell which are benign and which are malignant."

Wilson, Benos and colleagues gathered low-dose CT scan data from 218 high-risk UPMC patients who were later confirmed to have either lung cancer or benign nodules. Then they fed the data into a machine learning algorithm - a form of artificial intelligence - to create a model that calculates the probability of cancer. If the probability falls below a certain threshold, the model rules out cancer.

Comparing the model's assessment against the actual diagnoses of these patients, the researchers found that they would have been able to save 30 percent of the people with benign nodules from undergoing additional testing, without missing a single case of cancer.

The three factors that were most important to the model, Benos said, are the number of blood vessels surrounding the nodule, the number of nodules and the number of years since the patient quit smoking.

"While it has been known for some time that tumors recruit more vascular support, this is the first time that we've been able to use computer technology to quantify their contribution and incorporate them into a predictive model that decides, with certainty, that some patients don't have cancer," Wilson said. "The next step is to evaluate this technique in a larger population, and actually it's started already, using about 6,000 scans from the National Lung Screening Trial."

Science is known for being objective and apolitical, but is it? Historically speaking, the voices of underrepresented groups have been missing from science, resulting in an often incomplete and fragmented perspective of the world. Without these voices, we are left with skewed ideas about race, ethnicity, class, sex, gender, and sexuality, how these concepts get made, and how they affect people's lives. A new collection of essays published today in the Vital Topics Forum of American Anthropologist unpacks how increasingly diverse scientists speak back to these problems, by offering new and more complete understandings of human and nonhuman diversity. (An embargoed pdf of the essays is available upon request).

In these essays, scientists challenge us to move beyond thinking about race as innate and to consider its consequences, including how racism impacts people's bodies and lives. Others push against oversimplifications of sex, gender, and sexuality, highlighting how the complexities of human diversity have been erased. Scientists from diverse backgrounds also draw attention to the ways that their bodies and experiences shape access to science, and how barriers to participation limit the scope of scientific research.

Diversity in science is therefore about more than visibility and representation; it brings the opportunity to change science for the better. Changing who we are in science makes it possible to change what we know.

In 18 essays, 20 anthropologists from diverse sex, gender, class, racial, ethnic, and religious backgrounds reflect on who they are and how that informs their science. This Vital Topics Forum is co-edited by Deborah A. Bolnick, an associate professor of anthropology and member of the Institute of Systems Genomics at the University of Connecticut; Rick W. A. Smith, a postdoctoral fellow with the department of anthropology and the Neukom Institute for Computational Science at Dartmouth College; and Agustín Fuentes, Edmund P. Joyce C.S.C. Professor of Anthropology and chair of the department of anthropology at the University of Notre Dame. All three also contributed essays to the collection.

In their introduction to the series, Smith and Bolnick reflect on how science has always been a view from somewhere, and how "historically, biological anthropology has often reflected classist, patriarchal, heterosexist, white supremacist, and other settler colonial agendas."

"In this Vital Topics Forum, we question the ways that these agendas have shaped the practice of science and the framing of scientific knowledge, even as their influences have typically gone unrecognized," explains Bolnick.

"Marginalized people have always known that science is partial and political," notes Smith. "There's been this idea that 'real' science only includes a narrow set of perspectives about how the world works, but that's because access to science has long been denied to marginalized people. The resulting lack of diverse ideas in science isn't evidence of its neutrality, it is evidence of its exclusionism. Diversifying science brings with it the possibility of changing science itself."

"Science, including anthropology, has a long history of conducting research that has been deeply harmful and unethical," adds Bolnick. "Studies have sometimes been carried out without consent from the individuals and communities affected by the research, and science has often served to justify discrimination, racism, the displacement of Indigenous peoples from their ancestral homelands, and the enslavement, abuse, exploitation and oppression of marginalized peoples. Change is long overdue."

Recent studies have shown that more diverse research teams create higher quality outcomes. "This is not a conversation about identity politics but about shifting the narrative in science to better reflect who we are and how we make sense of the world around us. Diversity enhances the capacity of science to better understand the processes of the world. Including a broader array of histories and identities is essential, if we want to create the best quality science," says Fuentes.

This Vital Topics Forum grew out of a high-profile symposium at the 86th Annual American Association of Physical Anthropologists Meeting in 2017, during which researchers reflected on how historically marginalized scientists are reshaping the field of biological anthropology.

These pieces demonstrate the power of diversity to transform scientific knowledge in biological anthropology, providing a model for what is possible across other science, technology, engineering and mathematics (STEM) fields.

"Diversity is not just about visibility and representation," concludes Smith. "It is also about making new and vital science together."

WEST LAFAYETTE, Ind. - A fascination with movie technology that showed robots perform self-repair through a liquid formula inspired a Purdue University professor to make his own discoveries - which are now helping to lead the way for advancements in self-powering devices such as consumer electronics and defense innovations.

The Purdue team, led by Wenzhuo Wu, the Ravi and Eleanor Talwar Rising Star Assistant Professor of Industrial Engineering, has created wearable technology to convert mechanical energy into electrical energy. A video about the technology is available at https://youtu.be/TXo7zcijVjI.

"Our work presents an important step toward the practical realization of self-powered, human-integrated technologies," Wu said.

The Purdue team invented a liquid-metal-inclusion based triboelectric nanogenerator, called LMI-TENG. Triboelectric energy harvesting transducers - devices which help conserve mechanical energy and turn it into power - are predicted to be a $480 million market by 2028, according to IDTechEx.

The LMI-TENG can harvest and sense the biomechanical signals from the body and use those to help power and direct technological devices. The LMI-TENG consists of a layer of liquid metal embedded functional silicone sandwiched between two Ecoflex layers.

The Purdue technology is featured in the February edition of the Journal of Materials Chemistry A, which named it one of 2019's HOT papers.

"We realized that liquid represents the ultimate form of anything that can be deformable and morphing into different shapes," Wu said. "Our technology will enable wearable electronics to take otherwise wasted energy and transform it into energy that can power and control electronic devices and tools used in military defense and consumer applications. Our technology allows the synergistic engineering of TENG components at the material, structural and output levels."

Wu said the Purdue technology has applications for many self-powered innovations for emerging technologies, such as wearable sensors, pervasive computing, advanced health care, human-machine interfaces, robotics, user interfaces, augmented reality, virtual reality, teleoperation and the Internet of Things.

AMHERST, Mass. - A persistent question among urban ecology researchers has been the long-term impact of urbanization on bird species biodiversity. Specifically, they wonder whether the portions of cities with higher diversity are simply exhibiting an "extinction debt" - populations doomed to extinction but not yet disappeared - or if other factors such as range shifts or local environmental changes play a role in changes in diversity.

Now, researchers led by co-first authors Paige S. Warren at UMass Amherst and Susannah B. Lerman of the USDA Forest Service, with Riley Andrade, Kelli Larson and Heather Bateman of Arizona State University, report on results from their long-term monitoring of birds in the Phoenix metropolitan area. Details appear in the current online issue of Ecosphere.

The study looked at bird communities over time in relation to habitat, societal factors, human responses and bird populations. Findings suggest that although the presence of bird species, bird abundance and the number of bird species all decreased over time, in areas where homeowners provided desert landscaping - fine gravel and drought-tolerant, desert-adapted vegetation - some desert specialist birds such as verdin and cactus wren could still be found.

The researchers also report observing socio-economic factors associated with species diversity. For example, the desert-like landscaping types and desert specialist bird species occurred more frequently in neighborhoods with higher per-capita incomes and lower percentages of renters and Hispanic/Latinx residents. Warren notes that including socioeconomic factors has become more common recently, but it's still unusual. Their earlier work "was truly ground-breaking with respect to including socioeconomic factors," she says.

"The fact that all kinds of species were declining is particularly surprising and troubling to us," says Lerman. However, Warren adds, "Our results suggest that if we could find ways to encourage homeowners to provide more areas with desert-like plantings, there are opportunities to retain the richness of bird species, even in people's back yards."

Doug Levey, an NSF Long-Term Ecological Research (LTER) program director, says, "It's surprising and worrisome that birds are declining in neighborhoods that appear otherwise unchanged. Something is going on and these scientists are well on the way to figuring it out."

As noted, this study built upon an earlier investigation in the same area by Warren and Lerman, who found positive associations between certain bird species and landscaping arrangements such that desert birds were found associated with desert-like landscaping. They also found greater resident satisfaction in neighborhoods with greater bird diversity, and neighborhoods with wealthier residents had more localized bird species.

Five years after the first study, the researchers revisited the same sites to evaluate changes in bird species composition in the context of bird population trends, plus local environmental changes in habitat and land use, to see what species persisted over time, whether desert birds continue to associate with desert-like landscapes, whether socio-economic inequalities in access to bird diversity persist and whether these affect resident satisfaction with bird variety.

Warren, Lerman and colleagues conducted the investigation in the National Science Foundation's (NSF) Central Arizona-Phoenix (CAP) LTER site in the same 39 neighborhoods sampled five years earlier. They and colleagues surveyed birds twice per year, characterized landscape type and administered a household survey to gauge neighborhood satisfaction with local birds. They used census data to characterize neighborhood socio-economic features and local maps to identify land use changes. Dan Childers, CAP LTER director, says, "This excellent paper demonstrates that inter-disciplinary socio-ecological analysis of long-term data is critical to helping us better understand urban ecosystem dynamics."

The authors report that average bird occupancy - the proportion of places where a species is found - decreased between the two periods by 9 percent, from 46.7 to 37.8 percent, and note that six of 11 desert specialist species declined. Also, there were fewer desert bird species recorded during the second time period. However, half of the generalist bird species and half of the invader species remained stable.

Landscape types showed little change; in particular the number of desert-like landscapes was the same between periods, they note. Census data showed a shift toward more Hispanic/Latinx residents and fewer Anglo residents, while income and education levels did not change. Similarly, associations between desert birds in higher income neighborhoods and more exotic species found in Hispanic/Latinx neighborhoods remained consistent through the two sampling periods, even though the types of birds shifted over time.

Overall, the authors report, "the decline in bird species/change in composition is driven by factors other than changing demographics or landscapes." They add, "We documented significant losses in species richness and abundance, particularly for desert specialist species across a five-year period. However, some of the obvious mechanisms of regional population trends or local-scale environmental change do not appear to account for these losses, raising the possibility of an extinction debt."

Warren says, "The declines we found here mirror similar declines found over a 12-year period in riparian habitats in Phoenix, suggesting this is not just a five-year dip." Lerman adds that a loss of species in residential yards could significantly affect residents' access to a vibrant and unique desert fauna, and she hopes that this information "will inspire residents and local gardening organizations to landscape with birds in mind."

Childers points out, "Cities are designed, built and managed as human habitat, and these findings demonstrate how our decisions about that affect other species that share our urban ecosystems with us. These 'lessons learned' also provide valuable input as we work with urban practitioners to help move our cities towards more sustainable futures."

A new study in the Review of Economic Studies finds that U.S. counties with more historical immigration have higher incomes, less poverty, and lower unemployment today.

An important issue in current American political discourse is the effect that immigrants have on the communities in which they settle. While this topic has received significant attention, the focus has generally been on the short-term effects of immigrants. We know much less about the long-run consequences of immigration.

Researchers studied the effects of immigration into the United States from 1850 to 1920, a period in which immigration to the country increased dramatically, and the immigration sources also changed. In 1850 over 90% of foreign-born people living in the United States were from Great Britain, Ireland, or Germany. By 1920, this figure was only 45%.

The authors found that immigration resulted in benefits that were felt soon after their arrival. Immigration resulted in more and larger manufacturing establishments, greater agricultural productivity, and higher rates of innovation. These findings are consistent with a long-standing narrative suggesting that immigrants contribute to economic growth by providing an ample supply of unskilled labor, as well as a smaller supply of skilled people, who bring with them knowledge and innovations that are important for development.

The size of the effects suggest that increasing the percentage of immigrants in a county by 4.9% results in a 13% increase in average per capita income today, a 44% increase in average manufacturing output per capita from 1860-1920 (and a 78% increase in 1930), a 37% increase in farm values, and a 152% increase in the number of patents per capita.

The researchers also found that these economic benefits did not have long-run social costs. Places with more historical immigrant settlement today have similar levels of social capital, civic participation, and crime rates.

"What is fascinating is that despite the exceptionalism of this period in US history," said the paper's lead author, Sandra Sequeira. "There are several important parallels that one could draw between then and now: the large influx of unskilled labor, the small but important inflow of highly skilled innovators, as well as the significant short-run social backlash against immigration. There is much to be learned from taking a longer perspective on the immigration debate."

WASHINGTON -- In late 2018, the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft arrived at Bennu, the asteroid it will be studying and sampling over the next several years.

Now, new research in the AGU journal Geophysical Research Letters shows Bennu is spinning faster over time - an observation that will help scientists understand the evolution of asteroids, their potential threat to Earth and if they could be mined for resources.

Bennu is 110 million kilometers (70 million miles) away from Earth. As it moves through space at about 101,000 kilometers per hour (63,000 miles per hour), it also spins, completing a full rotation every 4.3 hours.

The new research finds the asteroid's rotation is speeding up by about 1 second per century. In other words, Bennu's rotation period is getting shorter by about 1 second every 100 years.

While the increase in rotation might not seem like much, over a long period of time it can translate into dramatic changes in the space rock. As the asteroid spins faster and faster over millions of years, it could lose pieces of itself or blow itself apart, according to the study's authors.

Detecting the increase in rotation helps scientists understand the types of changes that could have happened on Bennu, like landslides or other long-term changes, that the OSIRIS-REx mission will look for.

"As it speeds up, things ought to change, and so we're going to be looking for those things and detecting this speed up gives us some clues as to the kinds of things we should be looking for," said Mike Nolan, a senior research scientist at the Lunar and Planetary Laboratory at the University of Arizona in Tucson, who is the lead author of the new paper and the head of the OSIRIS-REx mission's science team. "We should be looking for evidence that something was different in the fairly recent past and it's conceivable things may be changing as we go."

The OSIRIS-REx mission is scheduled to bring a sample of Bennu to Earth in 2023. Understanding Bennu's rotational change could help scientists figure out what asteroids can tell us about the origin of the solar system, how likely it is for asteroids to pose a threat to humans and if they could be mined for resources.

"If you want to do any of those things, you need to know what is affecting it," Nolan said.

Detecting a change

In order to understand Bennu's rotation, scientists studied data of the asteroid taken from Earth in 1999 and 2005, along with data taken by the Hubble Space Telescope in 2012. It was when they looked at the Hubble data that they noticed the rotation speed of the asteroid in 2012 didn't quite match their predictions based on the earlier data.

"You couldn't make all three of them fit quite right," Nolan said. "That was when we came up with this idea that it had to be accelerating."

The idea that the rotation of asteroids could speed up over time was first predicted around 2000 and first detected in 2007, according to Nolan. To date, this acceleration has only been detected in a handful of asteroids, he said.

The change in Bennu's rotation could be due to a change in its shape. Similar to how ice skaters speed up as they pull in their arms, an asteroid could speed up as it loses material.

Nolan and his co-authors suggest the reason for the increase in Bennu's rotation is more likely due to a phenomenon known the YORP effect. Sunlight hitting the asteroid is reflected back into space. The change in the direction of the light coming in and going out pushes on the asteroid and can cause it to spin faster or slower, depending on its shape and rotation.

The OSIRIS-REx mission will determine Bennu's rotation rate independently this year, which will help scientists nail down the reason for the increase in rotation. Since spacecraft will never visit the vast majority of asteroids, the measurements will also help scientists learn how well ground-based measurements are able to understand these far-away objects.

"By testing these predictions in a few cases, we will significantly improve our confidence in predictions made for other objects," the study's authors write.

The measurement of Bennu's acceleration rate combined with the arrival of OSIRIS-REx at the asteroid gives scientists a great opportunity to validate the new study's results and test theories about the YORP effect, said Desiree Cotto-Figueroa, an assistant professor of physics and electronics at the University of Puerto Rico at Humacao, who was not involved in the new study.

"This is a great opportunity, in general, having this measurement and having the spacecraft OSIRIS-REx there observing this asteroid to help us better understand this effect, which is a dominant mechanism in the evolution of asteroids," she said.

MISSOULA - New University of Montana research suggests climate change makes it increasingly difficult for tree seedlings to regenerate following wildfires in low-elevation forests, which could contribute to abrupt forest loss.

The study, "Wildfires and Climate Change Push Low-elevation Forests Across a Critical Climate Threshold for Tree Regeneration," was published March 11 in the Proceedings of the National Academy of Sciences and is available online at http://bit.ly/2HeZc8t.

Kimberley Davis, a postdoctoral research associate in the W.A. Franke College of Forestry and Conservation at UM, and her co-authors examined the relationship between annual climate and post-fire regeneration of ponderosa pine and Douglas fir in low-elevation forests of western North America.

"Forests in the western U.S. are increasingly affected by both climate change and wildfires," said Davis, the study's lead author. "The ability of forests to recover following wildfire depends on annual climate conditions, because tree seedlings are particularly vulnerable to hot and dry weather. We wanted to identify the specific conditions necessary for post-fire tree regeneration to better understand how climate change has been affecting forests through time."

The authors used tree rings to determine establishment dates of more than 2,800 trees that regenerated after fires in Arizona, California, Colorado, Idaho, Montana and New Mexico between 1988 and 2015. Annual tree regeneration rates were much lower when seasonal climate conditions, including temperature, humidity and soil moisture, crossed specific threshold values.

Over the past 20 years, climate conditions have crossed these thresholds at the majority of study sites, leading to abrupt declines in how often annual conditions are suitable for tree regeneration. The study results highlight how future fires in similar sites may catalyze transitions from forest to non-forest ecosystems.

"Adult trees can survive in warmer and drier conditions than seedlings, and our study found that some low-elevation areas that are currently forested no longer have climate conditions that are suitable for tree regeneration," Davis said. "In these areas, high-severity fire may lead to ecosystem transitions from forests to grasslands or shrublands.

"It is important to understand how climate change and wildfires will affect tree regeneration because forests are important economically, ecologically and culturally," she said. "Ponderosa pine and Douglas fir are two of the most dominant tree species in the western U.S., and they are critical for the regional forestry industry. Forests also contain high levels of biodiversity and provide a variety of ecosystem services, such as carbon sequestration and water regulation and supply. Additionally, people love to recreate in forests, which is an increasingly important part of the economy in western states."