Friday, February 14, 2020

HEY DOUGH BOY

WWI helmets protect against shock waves just as well as modern designs

iomedical engineers from Duke University have demonstrated that, despite significant advancements in protection from ballistics and blunt impacts, modern military helmets are no better at protecting the brain from shock waves created by nearby blasts than their World War I counterparts. And one model in particular, the French Adrian helmet, actually performed better than modern designs in protecting from overhead blasts.

The research could help improve the blast protection of future helmets through choosing different materials, layering multiple materials of different acoustic impedance, or altering their geometry.

The results appeared online on February 13 in the journal PLOS ONE.

"While we found that all helmets provided a substantial amount of protection against blast, we were surprised to find that the 100-year-old helmets performed just as well as modern ones," said Joost Op 't Eynde, a biomedical engineering PhD student at Duke and first author of the study. "Indeed, some historical helmets performed better in some respects."

Researchers have only recently begun to study the brain damage a shock wave can cause on its own—and for good reason. Helmets were originally designed to protect from penetrating objects like bullets and shrapnel, and blast waves will kill through pulmonary trauma long before they cause even minor brain damage.

With the advent of body armor, however, soldiers' lungs are much more protected from such blasts than they used to be. This has caused the incidence of pulmonary trauma following a blast to drop far below that of brain or spine injuries in modern military conflicts, despite the difference in blast tolerance.

While there have been studies that suggest modern helmets provide a degree of protection from shock waves, no currently deployed helmet has been specifically designed for blast protection. And because soldiers today experiencing shock waves while wearing body armor aren't all that different from soldiers 100 years ago experiencing shock waves while in the trenches, Op 't Eynde decided to see if those old designs offered any lessons to be learned.

"This study is, to the best of our knowledge, the first to assess the protective capabilities of these historical combat helmets against blasts," said Op 't Eynde.

Working with Cameron "Dale" Bass, associate research professor of biomedical engineering at Duke, Op 't Eynde created a system to test the performance of World War I helmets from the United Kingdom/United States (Brodie), France (Adrian), Germany (Stahlhelm) and a current United States combat variant (Advanced Combat Helmet).

The researchers took turns placing different helmets on a dummy's head outfitted with pressure sensors at various locations. They then placed the head directly underneath a shock tube, which was pressurized with helium until a membrane wall burst, releasing the gas in a shock wave. The helmets were tested with shock waves of varying strength, each corresponding to a different type of German artillery shell exploding from a distance of one to five meters away.

The amount of pressure experienced at the crown of the head was then compared to brain injury risk charts created in previous studies. While all helmets provided a five-to-tenfold reduction in risk for moderate brain bleeding, the risk for someone wearing a circa-1915 French "Adrian" helmet was less than for any of the other helmets tested, including the modern advanced combat helmet.

"The result is intriguing because the French helmet was manufactured using similar materials as its German and British counterparts, and even had a thinner wall," said Op 't Eynde. "The main difference is that the French helmet had a crest on top of its crown. While it was designed to deflect shrapnel, this feature might also be deflecting shock waves."

t also might be that, because the pressure sensor was mounted directly under the crest, the crest provided an additional first layer for reflecting the shock wave. And the French helmet did not show the same advantage in pressure sensors at any other location. For locations such as the ears, performance seemed to be dictated by the width of the helmet's brim and just how much of the head it actually covered.

As for the modern helmet, Op 't Eynde theorizes that its layered structure might be important in its performance. Because a shock wave is reflected every time it encounters a new material with a different acoustic impedance, the layered structure of the modern helmet might contribute to its blast protection.

But no matter which helmet was tested, the results clearly indicated that helmets might play an especially important role in protecting against mild blast-induced brain trauma. According to the researchers, this finding alone shows the importance of continuing this type of research to design helmets that can better absorb shock waves from nearby overhead explosions.

"The difference a simple crest or a wider brim can make in blast protection, shows just how important this line of research could be," said Op 't Eynde, who initially came to Duke on a scholarship from the Belgian American Educational Foundation, which was established with funds from American relief efforts in Belgium during World War I. "With all of the modern materials and manufacturing capabilities we possess today, we should be able to make improvements in helmet design that protects from blast waves better than helmets today or 100 years ago."Material for safer football helmets may reduce head injuries

More information: Joost Op 't Eynde et al. Primary blast wave protection in combat helmet design: A historical comparison between present day and World War I, PLOS ONE (2020). DOI: 10.1371/journal.pone.0228802

Green tea extract combined with exercise reduces fatty liver disease in mice

by Jeff Mulhollem, Pennsylvania State University

The combination of green tea extract and exercise reduced the severity of obesity-related fatty liver disease by 75% in mice fed a high-fat diet, according to Penn State researchers, whose recent study may point to a potential health strategy for people.

The outcome is important, explained Joshua Lambert, associate professor of food science, because nonalcoholic fatty liver disease is a significant global health problem that is expected to worsen. Because of the high prevalence of risk factors such as obesity and type 2 diabetes, fatty liver disease is forecast to afflict more than 100 million people by 2030. And there are currently no validated therapies for the disease.

In the study, mice fed a high-fat diet for 16 weeks that consumed green tea extract and exercised regularly by running on a wheel were found to have just a quarter of the lipid deposits in their livers compared to those seen in the livers of a control group of mice. Mice that were treated with green tea extract alone or exercise alone had roughly half as much fat in their livers as the control group.

In addition to analyzing the liver tissues of mice in the study, which was published recently in the Journal of Nutritional Biochemistry, researchers also measured the protein and fat content in their feces. They found that the mice that consumed green tea extract and exercised had higher fecal lipid and protein levels.

"By examining the livers of these mice after the study concluded and by screening their feces during the research, we saw that the mice that consumed green tea extract and exercised actually were processing nutrients differently—their bodies were handling food differently," Lambert said.

"We think the polyphenols in green tea interact with digestive enzymes secreted in the small intestine and partially inhibit the breakdown of carbohydrates, fat and protein in food," he added. "So, if a mouse doesn't digest the fat in its diet, that fat and the calories associated with it pass through the mouse's digestive system, and a certain amount of it ends up coming out in its feces."

It may be significant, Lambert explained, that mice treated with both green tea extract and exercise had higher expression of genes related to the formation of new mitochondria. That gene expression is important, he said, because it provides markers that will help researchers understand the mechanism by which green tea polyphenols and exercise might work together to mitigate fatty liver deposits.

"We measured the expression of genes that we know are related to energy metabolism and play an important role in energy utilization," Lambert said. "In the mice that had the combination treatment, we saw an increase in the expression of genes that wasn't there before they consumed green tea extract and exercised."

More research is needed to see if there is a synergy created by green tea extract and exercise working together to reduce fat deposited in the liver, or if the effects are simply additive, Lambert pointed out. His research group in the College of Agricultural Sciences for 12 years has studied the health benefits of polyphenols—often called antioxidants—from green tea, cocoa, avocados and other sources.

In previous related research, Lambert and colleagues demonstrated that green tea extract and exercise together sharply reduced body mass and improved cardiovascular health of high-fat-fed mice. But because no human trials assessing the health benefits and risks of green tea combined with exercise have been conducted, he urges caution for people who decide to experiment with the health strategy on their own.

"I believe people should engage in more physical activity, and replacing high-calorie beverages with decaffeinated, diet green tea—which has no calories—is a smart move," he said. "Combining the two might have health benefits for people, but we don't have the clinical data Research suggests that green tea, exercise boost weight loss, health

More information: Weslie Y. Khoo et al, Mitigation of nonalcoholic fatty liver disease in high-fat-fed mice by the combination of decaffeinated green tea extract and voluntary exercise, The Journal of Nutritional Biochemistry (2019). DOI: 10.1016/j.jnutbio.2019.108262

Cannabis use consistently leads to increase in susceptibility to false memories

by Bob Yirka , Medical Xpress

Credit: CC0 Public Domain

A team of researchers from The Netherlands, Belgium, Australia, Germany and the U.S. has found evidence showing that the use of cannabis consistently leads to an increase in susceptibility to false memories. In their paper published in Proceedings of the National Academy of Sciences, the group describes double-blind, randomized, placebo-controlled trials that they used to test the impact of cannabis use on memory recall, and what they found.

Prior research has shown that smoking cannabis can lead to memory loss, and in some cases, memory distortion. In this new effort, the researchers wanted to know if THC, the active ingredient in cannabis, can also lead to an increase in susceptibility to false or implanted memories.

To find out whether people smoking a vaporized form of THC are more susceptible to suggested false memories, the researchers enlisted the assistance of 64 people who self-described as occasional users of cannabis. Each was given a dose of the drug (except those in a control group) and were then given memory tests. One of the memory tests involved reading and reciting a list of words. Another involved answering questions after watching a virtual reality-based fake fight between two people on a train. In the third, each volunteer took part in a virtual reality simulation where they assumed the role of a character who steals money from an unknown person's purse. In each scenario, the memory tests were phrased in ways meant to influence the recall of the volunteers. And some questions introduced false information. In testing the volunteers, the researchers went to great lengths to assure the subjects that they were not being influenced themselves and were not influencing the volunteers in unknown ways.

After analyzing the results of the tests, the researchers claimed that their study showed smoking THC very clearly increased the subjects' susceptibility to forming false memories based on false information provided to them during a memory testing process. They suggest that their findings be taken into consideration by law enforcement when interviewing witnesses to a crime. They next plan to look into the possibility of misinformation leading to false confessions in criminal interrogations in which an accused person is under the influence of cannabis.

Explore furtherFirst-person memories stay sharper longer, research suggests
More information: Lilian Kloft et al. Cannabis increases susceptibility to false memory, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.1920162117
Journal information: Proceedings of the National Academy of Sciences

Fake news makes disease outbreaks worse, research shows

by University of East Anglia

The rise of fake news could be making disease outbreaks worse—according to new research from the University of East Anglia (UEA).

Researchers focused on influenza, monkeypox and norovirus across two studies—but they say their findings could also be useful for dealing with the COVID-19 Coronavirus outbreak.

The team say that efforts to stop people sharing fake news, misinformation and harmful advice on social media could save lives.

The worry that fake news might be used to distort political processes or manipulate financial markets is well established. But less studied is the possibility that misinformation spread could harm human health, especially during the outbreak of an infectious disease.

COVID-19 expert Prof Paul Hunter and Dr. Julii Brainard, both from UEA's Norwich Medical School, set out to test the effect of sharing dangerously wrong information on human health during a disease outbreak.

Prof Hunter said: "Fake news is manufactured with no respect for accuracy, and is often based on conspiracy theories.

"Worryingly, research has shown that nearly 40 per cent of the British public believe at least one conspiracy theory, and even more in the US and other countries.

"When it comes to COVID-19, there has been a lot of speculation, misinformation and fake news circulating on the internet—about how the virus originated, what causes it and how it is spread.

"Misinformation means that bad advice can circulate very quickly—and it can change human behaviour to take greater risks.

"We have already seen how the rise of the anti-vax movement has created a surge in measles cases around the world.

"People in West Africa affected by the Ebola outbreak were more likely to practice unsafe burial practices if they believed misinformation. And here in the UK, 14 per cent of parents have reported sending their child to school with symptoms of contagious chickenpox—violating school policies and official quarantine advice.

"Examples of risky behaviour during infectious disease outbreaks include not washing hands, sharing food with ill people, not disinfecting potentially contaminated surfaces, and failing to self-isolate.

"Worryingly, people are more likely to share bad advice on social media, than good advice from trusted sources such as the NHS, Public Health England or the World Health Organisation."

The researchers created theoretical simulations which took into account studies of real behaviour, how different diseases are spread, incubation periods and recovery times, and the speed and frequency of social media posting and real-life information sharing.

They also took into account how a distrust in conventional authorities is closely linked to the tendency to believe in conspiracy theories, the phenomena that people interact within 'information bubbles' online, and the fact that people are more likely to share false stories than correct information online.

The researchers also investigated strategies to fight fake news—such as drowning bad information with good information and 'immunizing' people against bad information though better education.

Dr. Julii Brainard said: "No previous studies have looked in such detail at how the spread of misinformation affects the spread of disease.

"We found that misinformation during epidemics of infectious disease could make those outbreaks more severe.

"We tested strategies to reduce misinformation. In our first study, focusing on the flu, monkeypox and norovirus, we found that reducing the amount of harmful advice being circulated by just 10 per cent—from 50 percent to 40 per cent—mitigated the influence of bad advice on the outcomes of a disease outbreak.

"Making 20 per cent of the population unable to share or believe harmful advice—or 'immunizing' them against fake news, had the same positive effect.

"Our second study, which focused on norovirus, showed that even if 90 per cent of the advice is good, some disease will still circulate.

"In our second study, we were also interested in the 'herd immunity' levels required to 'immunise' people against fake news. The modelling suggests that any 'immunity' against bad advice reduces outbreak impacts.

"But while we used very sophisticated simulation models, it is important to remember that this is not an observational study based on real behaviour," she added.

"The efficacy of implementing such strategies to fight fake news needs to be tested in real world settings, with costs and benefits ideally compared with real world disease reduction."Online game has transnational impact as 'vaccine' against fake news

More information: 'Misinformation making a disease outbreak worse: outcomes compared for influenza, monkeypox and norovirus' is published in the journal Simulation: Transactions of the Society for Modelling and Simulation International.

'An agent-based model about the effects of fake news on a norovirus outbreak' is published in the journal Revue-Depidemiologie-Et-De-Sante-Publique on Friday, February 14, 2020.

Forests bouncing back from beetles, but elk and deer slowing recovery

by Kelsey Simpkins, University of Colorado at Boulder

Two words, and a tiny little creature, strike fear in the hearts of many Colorado outdoor enthusiasts: bark beetle. But new research from University of Colorado Boulder reveals that even simultaneous bark beetle outbreaks are not a death sentence to the state's beloved forests.

The study, published this month in the journal Ecology, found that high-elevation forests in the southern Rocky Mountains actually have a good chance of recovery, even after overlapping outbreaks with different kinds of beetles. One thing that is slowing their recovery down: Foraging elk and deer.

"This is actually a bright point, at least for the next several decades," said Robert Andrus, lead author of the study and recent Ph.D. graduate in physical geography. "Even though we had multiple bark beetle outbreaks, we found that 86 percent of the stands of trees that we surveyed are currently on a trajectory for recovery."

Between 2005 and 2017, a severe outbreak of spruce bark beetles swept through more than 741,000 acres of high-elevation forest in the southern Rocky Mountains near Wolf Creek Pass—killing more than 90 percent of Engelmann spruce trees in many stands. At the same time, the western balsam bark beetle infested subalpine fir trees across almost 124,000 acres within the same area.

If you go skiing in Colorado, you're usually in a high-elevation, Engelmann spruce and subalpine fir forest, said Andrus.

The researchers wanted to know if these overlapping events, caused by two different types of bark beetles, would limit the ability of the forest to recover. So they measured more than 14,000 trees in 105 stands in the eastern San Juan Mountains, tallying the surviving species and the number of deaths. They had expected that the combined effects of two bark beetle outbreaks would prevent forest recovery, but they found that the forests were quite resilient.

That's an important contrast from what happens following a severe fire, which can cause forests to convert to grasslands, according to previous research by Thomas Veblen, coauthor of the study and Distinguished Professor of Geography.

"It's important that we perform these sorts of studies, because we need different management responses depending on the forest type and the kind of disturbance," said Veblen.

They also found that greater tree species diversity prior to the bark beetle outbreaks was a key component of resilient forests.

Tens of millions of acres across the Western United States and North America have been affected in the past two decades, and Colorado has not been spared. A severe mountain pine beetle outbreak began in 1996, easily visible along I-70 and in Rocky Mountain National Park. Since 2000, more than 1.8 million acres of Engelmann spruce statewide have been affected by spruce beetles in high-elevation forests.

With continued warming there will come a time where conditions caused by climate change exceed the forests' ability to recover, said Veblen.

Impacts of Ungulates

The study is the first to consider the effects of two different types of beetles that affect two different dominant tree species, as well as the effects of browsing elk and deer in the same area.

Bark beetles prefer bigger, mature trees with thicker bark, which offer more nutrients and better protection in the wintertime. They typically leave the younger, juvenile trees alone—allowing the next generation to recover and repopulate the forest.

But while in the field, researchers noticed many smaller trees were being munched on by elk and deer. Known as "ungulates," these animals like to nibble the top of young trees, which can stunt the trees' vertical growth. They found more than half of the tops of all smaller trees had been browsed.

That doesn't mean that those trees are going to die—ungulates are just more likely to slow the rate of forest recovery.

Avid Colorado skiers and mountaineers looking forward to typical, green forests, however, will have to be patient.

"We don't expect full forest recovery for decades," said Andrus.Early detection of European spruce bark beetles with remote sensing

More information: Robert A. Andrus et al, Forest recovery following synchronous outbreaks of spruce and western balsam bark beetle is slowed by ungulate browsing, Ecology (2020). DOI: 10.1002/ecy.2998

Journal information: Ecology Provided by University of Colorado

California agricultural employers, workers approach smoke concerns differently

by Amy Quinton, UC Davis

In 2018, California wildfires burned more than 1.8 million acres and caused smoke to drift hundreds of miles. As the frequency and intensity of wildfires increases with climate change, California agricultural workers are at greater risk of smoke exposure as they often have no option but to work outdoors.

A new study from researchers at the University of California, Davis, finds that while wildfires and smoke exposure are recognized by farmworkers and employers as a growing threat and safety concern, the means to address these concerns differs between the two groups.

"What stood out in this study is the substantial disparities between agricultural employers and farmworkers," said Heather Riden with the Western Center for Agricultural Health and Safety at UC Davis.

Riden, who led the research in partnership with the California Institute for Rural Studies, said that while growers and employers expressed concern about poor air quality at the time of the study in 2018, many had no clear plans or protocols for measuring air quality or managing workers in such conditions. While the public is advised to stay indoors due to poor air quality during a wildfire, agricultural work often continues.

The study also found that when farmworkers were offered protective masks, many found them difficult to use while working due to heat-related discomfort and chafing. Others believed wearing two bandanas over the mouth and nose would provide just as much protection.

Farmworkers' experience is compounded by economic need.

"Many farmworkers will continue working, even in unsafe conditions, to support their families. They don't have many other options," said Riden.

New regulations

Last year, the state Division of Occupational Safety and Health, better known as Cal/OSHA, enacted an emergency regulation requiring employers to take measures to protect workers from wildfire smoke when the Air Quality Index reaches 151 or greater, which is considered unhealthy. Riden said as CAL/OSHA begins to craft permanent regulations, she hopes it takes the study's findings into consideration.

"This highlights the need for better awareness for both agricultural employers and farmworkers about the health risks associated with wildfire smoke," said Riden. "Employers also need training materials and concrete steps they can take to protect workers."

To assist agricultural employers with meeting the requirements outlined in the newly adopted regulation, the Western Center for Agricultural Health and Safety developed training materials and an employer checklist.Air quality during and after wildfires

More information: Heather E. Riden et al, Wildfire Smoke Exposure: Awareness and Safety Responses in the Agricultural Workplace, Journal of Agromedicine (2020). DOI: 10.1080/1059924X.2020.1725699

San Diego aquarium breeds rare weedy sea dragon in captivity

A Southern California aquarium has successfully bred the rare weedy sea dragon, the lesser known cousin of the sea horse that resembles seaweed when floating.

San Diego's Birch Aquarium at Scripps Institution of Oceanography said in a news release Thursday that two weedy sea dragons have hatched this week, making the aquarium one of the few in the world to successfully breed the unusual fish.

The babies with leafy appendages are less than an inch long, and have eaten their first meal of tiny shrimp. The aquarium is keeping the delicate creatures out of public view for now.

The hatchlings come less than a year after the aquarium at the University of California, San Diego built what is believed to be one of the world's largest habitats for the sea dragons, whose native populations off Australia are threatened by pollution, warming oceans and the illegal pet and alternative medicine trades.

The 18-foot-long tank has 11 weedy sea dragons and three leafy sea dragons, which have never been bred in captivity.

The aquarium hopes to breed the two different kinds of sea dragons so scientists can learn more about the mysterious species. Little is known about them because their populations are so small and in remote areas.

Since 1995, the Birch Aquarium has bred 13 different seahorse species, sharing more than 5,000 juvenile seahorses with other aquariums around the world.

So far, only the weedy sea dragon has been bred in captivity, and only a handful of times.

The Aquarium of the Pacific in Long Beach was the first in the world to breed the weedy sea dragons in 2001. It also is trying to breed leafy sea dragons.

Sea dragons captivate visitors at California aquarium

Caribbean sharks in need of large marine protected areas

by Stony Brook University

Governments must provide larger spatial protections in the Greater Caribbean for threatened, highly migratory species such as sharks, is the call from a diverse group of marine scientists including Stony Brook University School of Marine and Atmospheric Sciences (SoMAS) Ph.D. Candidate, Oliver Shipley, and led by the conservation NGO Beneath the Waves in a letter to published in Science.

With up to one-third of all open ocean shark species threatened extinction due to overfishing, conservation strategies that protect areas where sharks spent significant portions of their time are becoming increasingly important. In light of recent calls to protect 30 percent of our oceans by 2030, large marine protected areas, which can stretch from 100,000 sq. km to over 300,000 sq. km, have emerged as a popular management tool for their potential to enhance ecological processes and promote sustainable fisheries. One of the greatest benefits of these large conservation zones is their potential to conserve sharks, which travel long distances and can connect multiple jurisdictions over short time periods.

The letter in Science states that the Greater Caribbean, which boasts some of the highest rates of marine biodiversity and contains some of the most migratory shark species in the world, has been overlooked in these conversations.

"Through conducting years of scientific research on sharks in the Caribbean, I have witnessed first-hand, the benefits that marine protected areas can have for shark populations," said Shipley, a close collaborator of Dr. Austin Gallagher, Chief Scientist at Beneath the Waves. "We hope that currently protected nations, such as The Bahamas, can carry the torch and provide a foundation on which to base broader policy. For this to be a success, we will need to continue to build strong relationships and further understand the needs of key stakeholder groups throughout the wider Caribbean. We are extremely confident that this is going to happen."

"The diversity of countries sharing ocean space in the Greater Caribbean is remarkable, and we know that migratory shark species connect many of these countries along their migrations," said Gallagher. "Though there are many examples of establishing marine protected areas in the region, there are few that are big enough to encompass the space use of large sharks, such as tiger sharks which can move thousands of miles per year."

Recent research suggests that sharks are surprisingly rare in many Caribbean nations, likely due to decades of unregulated overharvest. However, certain areas such as the Bahamas, which have banned longline fishing and protected sharks in recent decades, have benefitted from the significant socioeconomic inputs generated from live sharks in the diving industry, estimated to be over US $140 million per year.Large marine parks can save sharks from overfishing threat

More information: Jennifer Sills et al, The Caribbean needs big marine protected areas, Science (2020). DOI: 10.1126/science.abb0650

Journal information: Science

Tourists pose continued risks for disease transmission to endangered mountain gorillas

by Ohio University

A new Ohio University study shows that tourists are getting too close to mountain gorillas, potentially exposing the gorillas to deadly diseases. Credit: Nancy J. Stevens

Researchers at Ohio University have published a new study in collaboration with Ugandan scientists, cautioning that humans place endangered mountain gorillas at risk of disease transmission during tourism encounters.

Mountain gorillas (Gorilla beringei beringei) are an endangered species of great ape found only in eastern Africa. Over 40% of the 1,059 mountain gorillas that remain on the planet today reside in Bwindi Impenetrable National Park in southwestern Uganda, and these apes are the heart of a growing tourism industry that has incentivized their continued protection. But close proximity between humans and gorillas during tourism encounters presents well-documented risks for disease transmission.

Gorillas are particularly susceptible to infectious diseases that affect humans, and respiratory infections are the most common, causing up to 20% of sudden deaths in gorillas. Accordingly, the Uganda Wildlife Authority has developed rules to protect the health of the gorillas, limiting each habituated gorilla group to a single hour-long visit per day by a group of no more than eight tourists. Current rules emphasize that humans must maintain a seven-meter (or greater) distance from gorillas at all times, which in the absence of wind is the minimum safe distance to avoid a sneezed droplet carrying infectious particles.

A number of studies over the years have documented that not all tour groups respect the seven-meter rule.

A new Ohio University study shows that tourists are getting too close to mountain gorillas, potentially exposing the gorillas to deadly diseases. Credit: Nancy J. Stevens

In a new study published in Frontiers in Public Health, Ohio University researchers documented tourist-gorilla spacing during 53 gorilla treks during a recent tourism high season in Bwindi Impenetrable National Park. They report that although 96% of pre-trek briefings conducted by park rangers emphasized the need to maintain greater than seven-meter human-gorilla spacing, the seven-meter distance rule was violated in over 98% (52 out of 53) of the tours examined in the study. Using observational data collected at two-minute intervals during gorilla-viewing tourism encounters, the researchers documented that nearly 70% of all observations took place at a distance less than or equal to seven meters.

"Although I had heard tourists were getting too close to the gorillas, I was surprised by the extent of the problem," observed study co-author Annalisa Weber, a graduate student in the Environmental Studies Program at Ohio University when the research was conducted, and now a senior research associate at Emory University. "We found that seven-meter rule was violated in visits to all of the gorilla groups habituated at the time of the study. And in 14% of observations, human-gorilla spacing was three meters or less."

"This points to a growing pattern of risk that is a cause of concern to sustaining long term gorilla-viewing tourism," noted Dr. Gladys Kalema-Zikusoka, CEO of Conservation Through Public Health and a co-author on the study. "Action is needed to limit disease risks caused by tourists viewing mountain gorillas."

Importantly, the researchers also explored opportunities to improve tourist adherence to park rules. For example, over 73% of the 243 tourists surveyed in the study responded that that they would be willing to utilize precautionary measures to protect gorilla health, for example in wearing protective face masks during viewing encounters. Indeed, wearing masks is considered best practice among scientists working in primate conservation, and this measure is already in place in The Democratic Republic of the Congo, where tourists regularly wear protective face masks during gorilla tourism encounters.

The use of protective masks could have logistical and financial limitations, and the researchers urge that the best strategy is to encourage tourists to maintain a safe distance from gorillas. "As tourism increases, and gorillas become increasingly habituated to human presence, new strategies will be needed for endangered great ape populations to thrive into the future," observed Dr. Nancy Stevens, Professor in the Department of Biomedical Sciences in the Heritage College of Osteopathic Medicine at Ohio University and corresponding author on the study. "Fortunately, we have talked with many insightful and empowered park officials who are poised to take action to protect gorilla health."

Explore furtherFour rare mountain gorillas 'killed by lightning' in Uganda
More information: Annalisa Weber et al. Lack of Rule-Adherence During Mountain Gorilla Tourism Encounters in Bwindi Impenetrable National Park, Uganda, Places Gorillas at Risk From Human Disease, Frontiers in Public Health (2020). DOI: 10.3389/fpubh.2020.00001
Provided by Ohio University

Study: Effectiveness of program that pays farmers to conserve water

by Jon Niccum, University of Kansas

Study details effectiveness of Kansas program that pays farmers to conserve water — Plots of land in Finney County, Kansas, utilize irrigation water from the High Plains Aquifer. Credit: NASA.

Crops need water. And in the central United States, the increasing scarcity of water resources is becoming a threat to the nation's food production.

Tsvetan Tsvetanov, assistant professor of economics at the University of Kansas, has analyzed a pilot program intended to conserve water in the agriculture-dependent region. His article "The Effectiveness of a Water Right Retirement Program at Conserving Water," co-written with fellow KU economics professor Dietrich Earnhart, is published in the current issue of Land Economics.

"Residential water use is mostly problematic in California, and not so much here in Kansas. However, people don't realize that residential use is tiny compared to agricultural use," Tsvetanov said.

"I don't want to discourage efforts to conserve water use among residential households. But if we want to really make a difference, it's the agricultural sector that needs to change its practices."

That's the impetus behind the Kansas Water Right Transition Assistance Program (WTAP).

"If you're a farmer, you need water to irrigate. If you don't irrigate, you don't get to sell your crops, and you lose money. So the state says if you reduce the amount of water you use, it's actually going to pay you. So it's essentially compensating you to irrigate less," he said.

But this is not a day-to-day solution. The state recompenses farmers to permanently retire their water rights. The five-year pilot program that began in 2008 offers up to $2,000 for every acre-foot retired.

This benefits the High Plains Aquifer, the world's largest freshwater aquifer system, which is located beneath much of the Great Plains. Around 21 million acre-feet of water is withdrawn from this system, primarily for agricultural purposes.

Tsvetanov and Earnhart's work distinguishes the effectiveness between two target areas: creek sub-basins and high-priority areas. Their study (which is the first to directly estimate the effects of water right retirement) found WTAP resulted in no reduction of usage in the creek areas but substantial reduction in the high-priority areas.

"Our first thought was, "That's not what we expected,'" Tsvetanov said.

"The creeks are the geographic majority of what's being covered by the policy. The high-priority areas are called that for a reason—they've been struggling for many years. Our best guess is that farmers there were more primed to respond to the policy because there is awareness things are not looking good, and something needs to be done. So as soon as a policy became available which compensated them for the reduction of water use, they were quicker to take advantage of it."

Of the eight states sitting atop the High Plains Aquifer, Texas is the worst in terms of water depletion volume. However, Kansas suffers from the fastest rate of depletion during the past half-century.

"Things are quite dire," Tsvetanov said. "The western part of Kansas is more arid, so they don't get as much precipitation as we do here in the east. Something needs to change in the long run, and this is just the first step."

Tsvetanov initially was studying solar adoption while doing his postdoctoral work at Yale University in Connecticut. When visiting KU for a job interview, he assumed the sunny quality of the Wheat State would be a great fit for his research. He soon realized that few policies incentivized the adoption of solar.

"At that point, I thought, "I can't really adapt solar research to the state of Kansas because there's not much going on here." And then I started getting more interested in water scarcity because this truly is a big local issue," he said.

A native of Bulgaria who was raised in India (as a member of a diplomat's family), Tsvetanov is now in his fifth year at KU. He studies energy and environmental economics, specifically how individual household choices factor into energy efficiency and renewable resources.

The state of Kansas spent $2.9 million in the half decade that the WTAP pilot program ran. Roughly 6,000 acre-feet of water rights were permanently retired.

"Maybe it's a start, but it's not something you would expect to stabilize the depletion," Tsvetanov said. "This is just a drop in the bucket. Essentially what we need is some alternative source of income for those people living out there, aside from irrigation-intensive agriculture."Rural water wells in High Plains Aquifer show large increase in nitrate levels

More information: Tsvetan Tsvetanov et al. The Effectiveness of a Water Right Retirement Program at Conserving Water, Land Economics (2020). DOI: 10.3368/le.96.1.56

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