Tuning electrode surfaces to optimize solar fuel production

An electrode material with modified surface atoms generates more electrical current, which drives the sunlight-powered reactions that split water into oxygen and hydrogen--a clean fuel

DOE/BROOKHAVEN NATIONAL LABORATORY

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IMAGE: THROUGH A TIGHT COUPLING OF EXPERIMENT AND THEORY, SCIENTISTS SHOWED AT THE ATOMIC LEVEL HOW CHANGES IN THE SURFACE COMPOSITION OF A PHOTOELECTRODE PLAY A CRITICAL ROLE IN PHOTOELECTROCHEMICAL PERFORMANCE. view more 

CREDIT: UNIVERSITY OF CHICAGO

UPTON, NY--Scientists have demonstrated that modifying the topmost layer of atoms on the surface of electrodes can have a remarkable impact on the activity of solar water splitting. As they reported in Nature Energy on Feb. 18, bismuth vanadate electrodes with more bismuth on the surface (relative to vanadium) generate higher amounts of electrical current when they absorb energy from sunlight. This photocurrent drives the chemical reactions that split water into oxygen and hydrogen. The hydrogen can be stored for later use as a clean fuel. Producing only water when it recombines with oxygen to generate electricity in fuel cells, hydrogen could help us achieve a clean and sustainable energy future.

"The surface termination modifies the system's interfacial energetics, or how the top layer interacts with the bulk," said co-corresponding author Mingzhao Liu, a staff scientist in the Interface Science and Catalysis Group of the Center for Functional Nanomaterials (CFN), a U.S. Department of Energy (DOE) Office of Science User Facility at Brookhaven National Laboratory. "A bismuth-terminated surface exhibits a photocurrent that is 50-percent higher than a vanadium-terminated one."

"Studying the effects of surface modification with an atomic-level understanding of their origins is extremely challenging, and it requires tightly integrated experimental and theoretical investigations," said co-corresponding author Giulia Galli from the University of Chicago and DOE's Argonne National Laboratory.

"It also requires the preparation of high-quality samples with well-defined surfaces and methods to probe the surfaces independently from the bulk," added co-corresponding author Kyoung-Shin Choi from the University of Wisconsin-Madison.

Choi and Galli, experimental and theoretical leaders in the field of solar fuels, respectively, have been collaborating for several years to design and optimize photoelectrodes for producing solar fuels. Recently, they set out to design strategies to illuminate the effects of electrode surface composition, and, as CFN users, they teamed up with Liu.

"The combination of expertise from the Choi Group in photoelectrochemistry, the Galli Group in theory and computation, and the CFN in material synthesis and characterization was vital to the study's success," commented Liu.

Bismuth vanadate is a promising electrode material for solar water splitting because it strongly absorbs sunlight across a range of wavelengths and remains relatively stable in water. Over the past few years, Liu has perfected a method for precisely growing single-crystalline thin films of this material. High-energy laser pulses strike the surface of polycrystalline bismuth vanadate inside a vacuum chamber. The heat from the laser causes the atoms to evaporate and land on the surface of a base material (substrate) to form a thin film.

"To see how different surface terminations affect photoelectrochemical activity, you need to be able to prepare crystalline electrodes with the same orientation and bulk composition," explained co-author Chenyu Zhou, a graduate researcher from Stony Brook University working with Liu. "You want to compare apples to apples."

As grown, bismuth vanadate has an almost one-to-one ratio of bismuth to vanadium on the surface, with slightly more vanadium. To create a bismuth-rich surface, the scientists placed one sample in a solution of sodium hydroxide, a strong base.

"Vanadium atoms have a high tendency to be stripped from the surface by this basic solution," said first author Dongho Lee, a graduate researcher working with Choi. "We optimized the base concentration and sample immersion time to remove only the surface vanadium atoms."

To confirm that this chemical treatment changed the composition of the top surface layer, the scientists turned to low-energy ion scattering spectroscopy (LEIS) and scanning tunneling microscopy (STM) at the CFN.

In LEIS, electrically charged atoms with low energy--in this case, helium--are directed at the sample. When the helium ions hit the sample surface, they become scattered in a characteristic pattern depending on which atoms are present at the very top. According to the team's LEIS analysis, the treated surface contained almost entirely bismuth, with an 80-to-20 ratio of bismuth to vanadium.

"Other techniques such as x-ray photoelectron spectroscopy can also tell you what atoms are on the surface, but the signals come from several layers of the surface," explained Liu. "That's why LEIS was so critical in this study--it allowed us to probe only the first layer of surface atoms."

In STM, an electrically conductive tip is scanned very close to the sample surface while the tunneling current flowing between the tip and sample is measured. By combining these measurements, scientists can map the electron density--how electrons are arranged in space--of surface atoms. Comparing the STM images before and after treatment, the team found a clear difference in the patterns of atomic arrangements corresponding to vanadium- and bismuth-rich surfaces, respectively.

"Combining STM and LEIS allowed us to identify the atomic structure and chemical elements on the topmost surface layer of this photoelectrode material," said co-author Xiao Tong, a staff scientist in the CFN Interface Science and Catalysis Group and manager of the multiprobe surface analysis system used in the experiments. "These experiments demonstrate the power of this system for exploring surface-dominated structure-property relationships in fundamental research applications."

Simulated STM images based on surface structural models derived from first-principle calculations (those based on the fundamental laws of physics) closely matched the experimental results.

"Our first-principle calculations provided a wealth of information, including the electronic properties of the surface and the exact positions of the atoms," said co-author and Galli Group postdoctoral fellow Wennie Wang. "This information was critical to interpreting the experimental results."

After proving that the chemical treatment successfully altered the first layer of atoms, the team compared the light-induced electrochemical behavior of the treated and nontreated samples.

"Our experimental and computational results both indicated that the bismuth-rich surfaces lead to more favorable surface energetics and improved photoelectrochemical properties for water splitting," said Choi. "Moreover, these surfaces pushed the photovoltage to a higher value."

Many times, particles of light (photons) do not provide enough energy for water splitting, so an external voltage is needed to help perform the chemistry. From an energy-efficiency perspective, you want to apply as little additional electricity as possible.

"When bismuth vanadate absorbs light, it generates electrons and electron vacancies called holes," said Liu. "Both of these charge carriers need to have enough energy to do the necessary chemistry for the water-splitting reaction: holes to oxidize water into oxygen gas, and electrons to reduce water into hydrogen gas. While the holes have more than enough energy, the electrons don't. What we found is that the bismuth-terminated surface lifts the electrons to higher energy, making the reaction easier."

Because holes can easily recombine with electrons instead of being transferred to water, the team did additional experiments to understand the direct effect of surface terminations on photoelectrochemical properties. They measured the photocurrent of both samples for sulfite oxidation. Sulfite, a compound of sulfur and oxygen, is a "hole scavenger," meaning it quickly accepts holes before they have a chance to recombine with electrons. In these experiments, the bismuth-terminated surfaces also increased the amount of generated photocurrent.

"It's important that electrode surfaces perform this chemistry as quickly as possible," said Liu. "Next, we'll be exploring how co-catalysts applied on top of the bismuth-rich surfaces can help expedite the delivery of holes to water."

###

The work by Choi and Galli was supported by the National Science Foundation and used computational resources of the University of Chicago's Research Computing Center. The work at the CFN was supported by the DOE Office of Science and carried out in the Materials Synthesis and Characterization and Proximal Probes Facilities.

Brookhaven National Laboratory is supported by the U.S. Department of Energy's Office of Science. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science.

Follow @BrookhavenLab on Twitter or find us on Facebook.

How lithium-rich cathode materials for high energy EV batteries store charge at hig

UNIVERSITY OF WARWICK

Research News

 

IMAGE: PHOTO OF THE OPERANDO X-RAY STUDIES BEING PERFORMED AT A SYNCHROTRON FACILITY. view more 

CREDIT: WMG, UNIVERSITY OF WARWICK

• By 2030 only EV's will be in production, meaning manufacturers are racing to create a high-energy battery that's affordable and charges efficiently, but conventional battery cathodes cannot reach the targets of 500Wh/Kg
• Lithium-excess cathodes offer the ability to reach 500Wh/Kg but unlocking their full capacity means understanding how they can store charge at high voltages.
• A new X-ray study lead by WMG, University of Warwick has resolved how the metals and oxygen facilitate the charge storage at high voltages.

High energy storage batteries for EVs need high capacity battery cathodes. New lithium-excess magnesium-rich cathodes are expected to replace existing nickel-rich cathodes but understanding how the magnesium and oxygen accommodate charge storage at high voltages is critical for their successful adaption. Research led by WMG, University of Warwick in collaboration with U.S. researchers employed a range of X-ray studies to determine that the oxygen ions are facilitating the charge storage rather than the magnesium ions.

Electric vehicles will one day dominate UK roads and are critical for eliminating CO2 emissions, but a major issue car manufacturers face is how to make an affordable long-lasting energy-dense battery that can be charged quickly and efficiently. There is therefore a race to make EV batteries with an energy storage target of 500 Wh/Kg, but these targets are not possible without changing to new cathode materials.

Although progress has continued over the last 10 years to push the performance of state-of-the-art nickel-rich cathodes for EV, the material is unable to provide the energy density needed. To increase the capacity more lithium needs to be used, which means going beyond the ability of nickel to store electron charge.

Lithium-excess magnesium-rich cathodes offer sufficient energy density but to reach ultimately reach energy storage targets of 500Wh/Kg we need to understand how the electron charge is stored in the material. Simply put, is the electron charge stored on the magnesium or oxygen sites.

In the paper, 'Whither Mn Oxidation in Mn-Rich Alkali-Excess Cathodes?', published in the Journal ACS Energy Letters today the 17th of February, researchers from WMG, University of Warwick have overcome a significant milestone in understanding of charge storage in lithium-excess magnesium-rich cathodes.

Li-excess compounds that involve conventional and non-conventional redox, conventional refers to metal ions changing their electron density. Reversibly changing the electron density on the oxygen (or oxygen redox) without it forming O2 gas is unconventional redox. Various computational models exist in the literature describing different mechanisms involving both, but careful x-ray studies performed while the battery is cycling (operando) are ultimately required to validate these models.

Researchers between the UK and US, led by WMG at the University of Warwick, performed operando x-ray studies to precisely quantify magnesium and oxygen species at high voltages. They demonstrated how x-ray beams could irreversibly drive highly oxidized magnesium (Mn7+) to trapped O2 gas irreversibly in other materials.

However, by performing careful operando x-ray studies that circumvented beam damage and observe only trace amounts of Mn7+ forming upon charging in Li-excess cathodes during battery cycling.

Professor Louis Piper, from WMG, University of Warwick explains:

"We have ultimately resolved that oxygen rather than metal redox is driving the higher capacity, which means we can now design better strategies to improve cycling and performance for this class of materials."

###

17 FEBRUARY 2021

NOTES TO EDITORS

High-res images available at:

https://warwick.ac.uk/services/communications/medialibrary/images/february_2021/operando_x-ray_louis_piper.jpg

Caption: Photo of the operando x-ray studies being performed at a Synchrotron facility.

Credit: WMG, University of Warwick

Paper available to view at: https://pubs.acs.org/toc/aelccp/0/0

Smartphone study points to new ways to measure food consumption

Method offers potential for precise means to gauge food insecurity, environmental stress

NEW YORK UNIVERSITY

Research News

 

A team of researchers has devised a method using smartphones in order to measure food consumption--an approach that also offers new ways to predict physical well-being.

"We've harnessed the expanding presence of mobile and smartphones around the globe to measure food consumption over time with precision and with the potential to capture seasonal shifts in diet and food consumption patterns," explains Andrew Reid Bell, an assistant professor in New York University's Department of Environmental Studies and an author of the paper, which appears in the journal Environmental Research Letters.

Food consumption has traditionally been measured by questionnaires that require respondents to recall what they ate over the previous 24 hours, to keep detailed consumption records over a three-to-four-day period, or to indicate their typical consumption patterns over one-week to one-month periods. Because these methods ask for participants to report behaviors over extended periods of time, they raise concerns about the accuracy of such documentation.

Moreover, these forms of data collection don't capture "real-time" food consumption, preventing analyses that directly link nutrition with physical activity and other measures of well-being--a notable shortcoming given the estimated two billion people in the world who are affected by moderate to severe food insecurity.

Finally, while food consumption as well as food production have a significant impact on the environment, "we do not yet have the tools to analyze food consumption in the same ways as we do for environmental variables and food production," write the study's authors, who also include Mary Killilea, a clinical professor in NYU's Department of Environmental Studies, and Mari Roberts, an NYU graduate student. "This is a critical gap, as it hampers our understanding of how environmental shocks carry through to become consumption shocks to households, communities, or regions and how responses to these shocks feed back into further environmental stress."

The team, which also included researchers from the University of Minnesota, Imperial College London, the Palli Karma-Sahayak Foundation, and Duke Kunshan University, turned to smartphones as an alternative means to track food consumption and its relationship to physical activity.

"Access to mobile devices is changing how we gather information in many ways, all the way down to the possibility of reaching respondents on their own time, on their own devices, and in their own spaces," explains Bell.

Participants included nearly 200 adults in Bangladesh who reported which among a set of general food types (e.g., nuts and seeds, oils, vegetables, leafy vegetables, fruits, meat and eggs, fish, etc.) their household had consumed in the immediately preceding 24 hours as well as which specific food items within the more general food types they had consumed (e.g., rice, wheat, barley, maize, etc.) and how much they ate. Finally, participants reported the age, gender, literacy, education level, occupation, height, and weight of each member of their household and as well as the following measures of their own physical well-being: whether they could stand up on their own after sitting down, whether they could walk for 5 kilometers (3.1 miles), and whether they could carry 20 liters (5.3 gallons) of water for 20 meters (65.6 feet). All of the information was entered by the participants on their phones using a data-collection app, with response rates as high as 90 percent.

"Food stress is dynamic, and people's needs--particularly for expectant mothers and young children--can change quickly," explains Bell. "Reaching respondents in real time allows us to map those changes in a way conventional approaches don't capture."

"Mainstreaming data collection by respondents themselves, through their own devices, would be transformative for understanding food security and for empirical social science in general," he adds. "It would mean their voices being counted through participation on their own time and terms, and not only by giving up a half-day or longer of work. For researchers, it would mean having connections to rural communities and a picture of their well-being all the time, not just when resources flow to a place in response to crisis, potentially unearthing an understanding of resilience in the face of stressors that has never before been possible."

The authors recognize concerns about smartphone availability in both rural and impoverished communities. However, they point to recent studies that show how digital technologies, such as mobile phones and satellites, have offered new ways for rural populations in developing countries to access savings, credit, and insurance.

"We now see mobile phone penetration almost everywhere in the world, with smartphone and mobile broadband subscriptions following the same trend," says Bell.

###

The study was supported by the Cereal Systems Initiative for South Asia (CSISA) of the Consultative Group on International Agricultural Research (CGIAR), with funding provided by the United States Agency for International Development (USAID), the Bill and Melinda Gates Foundation, the International Food Policy Research Institute, and the CGIAR Collaborative Research Program on Policies, Institutions, and Markets.

DOI: 10.1088/1748-9326/abe674

Social tool tracks brand reputation in real time and over the long term

NORTH CAROLINA STATE UNIVERSITY

Research News

 

An international team of researchers has developed a framework for assessing brand reputation in real time and over time, and built a tool for implementing the framework. In a proof of concept demonstration looking at leading brands, the researchers found that changes in a given brand's stock shares reflected real-time changes in the brand's reputation.

"We've developed something we call the Brand Reputation Tracker that mines social media text on Twitter and uses 11 different measures to give us an in-depth understanding of how users feel about individual brands," says Bill Rand, co-lead author of the paper and an associate professor of marketing in North Carolina State University's Poole College of Management.

The Brand Reputation Tracker is a way of implementing a framework based on the Rust-Zeithaml-Lemon value-brand-relationship framework. Measures include things like "coolness," "goods quality," "social responsibility," and "trustworthiness," but are then aggregated into three scores: value driver, brand driver and relationship driver.

The value driver score effectively measures whether stakeholders think a brand is a good value. The relationship driver score assesses how closely stakeholders identify themselves with the brand. And the brand driver score accounts for pretty much everything else, such as style and popularity.

"The text mining allows us to give a numeric value to each of the measures and each of the driver scores," says Rand, who is also executive director of NC State's Business Analytics Initiative. "And we are able to place those numeric values in context by comparing them to the measures and aggregate scores of other brands."

Because social media data are updated constantly, the researchers were able to identify changes in brand reputation in real time - as well as looking at trend data across days, weeks, months and years.

For this paper, the researchers looked at 100 popular brands as a proof of concept, demonstrating not just how the tool works but that it works. For example, the researchers found that - for those brands that were publicly traded on the stock market - changes in value, relationship and brand driver score were reflected in each brand's stock valuation.

"One possible path forward is to significantly expand the dataset of brands that we're assessing to get a broader understanding of the brand landscape," Rand says. "And because we lay out the methodology we used, this paper allows users to create their own versions of the tool. For example, users could choose to look only at brands within a given industry category. Or users could modify the tool to focus on other aspects of brand, such as using a framework to assess the extent to which a brand is viewed as 'green' or 'sustainable.'"

Rand also notes that previous ways of assessing brand reputation in a meaningful way required either access to a tremendous amount of corporate data or the ability to survey thousands of people on a regular basis.

"But the approach we've developed here is more accessible to medium-sized businesses. It requires only the creation of the initial tool - which is very doable. Then you can plug in publicly available user data from Twitter and start getting usable brand assessment information in real time."

###

The paper, "Real-Time Brand Reputation Tracking Using Social Media," appears in the Journal of Marketing. Co-lead authors of the paper are Roland T. Rust, Distinguished University Professor and David Bruce Smith Chair in Marketing at the University of Maryland's Robert H. Smith School of Business; and Ming-Hui Huang, Distinguished Professor of Electronic Commerce at National Taiwan University. Co-authors of the paper are Andrew Stephen, associate dean of research and L'Oreal Professor of Marketing at the Säid Business School at the University of Oxford; Gillian Brooks, assistant professor in marketing at King's Business School at King's College London; and Timur Chabuk, vice president of machine learning and advanced analytics at Perceptronics Solutions, Inc.

This work was done with support from the University of Oxford's Centre for Corporate Reputation, the Center for Excellence in Service at the University of Maryland, and Taiwan's Ministry of Science and Technology.

Paper: STEM skills gap modest among IT help desk workers

UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN, NEWS BUREAU

Research News

 

IMAGE: THE INCIDENCE OF PROLONGED HIRING DIFFICULTIES FOR WORKERS WITH SCIENCE AND TECHNOLOGY BACKGROUNDS IS CONSISTENT WITH PERSISTENT HIRING FRICTIONS AND NOT A "SKILLS GAP " IN THE LABOR MARKET FOR INFORMATION... view more 

CREDIT: PHOTO BY L. BRIAN STAUFFER

CHAMPAIGN, Ill. -- Workers with science, technology, engineering and math backgrounds are typically in high demand - but the demand isn't so overwhelming that a "skills gap" exists in the labor market for information technology help desk workers, one of the largest computer occupations in the U.S., says new research from a University of Illinois Urbana-Champaign expert who studies labor economics and work issues.

The incidence of prolonged hiring difficulties for STEM workers is modest, with only 11%-15% of IT help desks in the U.S. showing vacancy patterns that might be consistent with persistent hiring frictions, said Andrew Weaver, a professor of labor and employment relations at Illinois.

"There's a prevailing narrative in which the world changed with the computer revolution and workers never got the memo," he said. "Technology does have an impact on the labor market, but the data doesn't really support the 'skills gap' formulation. Hiring frictions do exist, but organizational characteristics, management strategy and the structure of the labor market turn out to be more predictive of hiring problems than skill requirements. In other research on manufacturing and on hiring lab technicians, I also found similar results."

Published in the journal ILR Review, the paper presents evidence from an original, nationally representative survey of information technology help desks that shows skills-based hiring frictions, but not a skills gap.

"When people generically bemoan skills gaps, they're often parroting unverified talking points," Weaver said. "They're only focusing on the supply side, the availability of workers in the labor market, while ignoring the role of firms and their influence on the demand side, which also matters a lot. If you want to make labor markets work better for everyone, you've got to think about both sides of the equation. You can't just have STEM-skill blinders on. You can't just tell people 'Learn to code' and assume that all our hiring problems are solved. That's not a good way to think about workers or labor markets."

Organizations that had implemented formal management systems such as Lean or Six Sigma also show a higher incidence of long-term vacancies. Such management practices could function as a signal to potential applicants for work intensification and a challenging job environment, thereby making the job less appealing to candidates, according to the paper.

"It runs against conventional wisdom, but the factors that are most associated with hiring difficulties involve insufficient human resources outreach efforts, management strategy and the structure of the labor market," he said. "Organizational factors play an important role. Employers that have recently decreased job training or that have a history of underinvestment in past recruitment efforts are more likely to report persistent unfilled vacancies."

As an occupation, IT help desk technician makes for a ripe target to study, Weaver said.

"It's the second-largest detailed computer-related occupation in the Bureau of Labor Statistics' classification system," he said. "So studying this particular job can reveal patterns that have national implications."

The results not only indicate that the incidence of persistent hiring difficulties is modest, but that the skill demands that predict hiring challenges often involve nontechnical skills that run counter to conventional wisdom. These include advanced writing and "soft skills" such as the ability to initiate new tasks without guidance from management.

"In the process of designing the survey, I interviewed IT help desk managers and talked to them about hiring difficulties," Weaver said. "A number of them mentioned that writing skills were really important because an IT help desk typically has all these angry people complaining about computer problems. So you have to be able to convey technical information in a sensitive, easily understandable way through written communication."

From a policy standpoint, the data implies that an overly narrow focus on STEM skills may not be the most appropriate strategy for improving labor-market outcomes, Weaver said.

"It's only by taking all these measures into account that we can arrive at an accurate picture of the nature of hiring frictions and labor-market challenges," he said.

One remedy for employers would be better funding and investment in human resources in the hiring process.

"Companies that underinvest in outreach or don't have sufficient personnel to cast their nets wide enough to do a good job at recruiting - that's very predictive of hiring difficulties," Weaver said.

The paper also points to evidence that reducing internal employee training tends to exacerbate hiring frictions.

"How an organization operates, its characteristics and its approach to human resources - all of that matters in the labor market," he said.

One result from the study involves market structure: Employers that have market power over employees tend to experience fewer long-term unfilled vacancies. Ultimately, more research is needed to flesh out the ways in which labor-market competition and power imbalances interact with hiring frictions, Weaver said.

"The bottom line is that all of these factors cast doubt on simple stories about technology-driven hiring problems and point to the importance of examining a broader range of organizational factors and market forces when addressing workforce challenges in STEM jobs," he said.

COVID-19 in Africa is severely underestimated, finds Zambia study by Boston University

A new study concluding out of Lusaka, Zambia last summer has found that as many as 19% (almost 1 in 5) of recently-deceased people tested positive for COVID-19

BOSTON UNIVERSITY SCHOOL OF MEDICINE

Research News

 

A new study concluding out of Lusaka, Zambia last summer has found that as many as 19% (almost 1 in 5) of recently-deceased people tested positive for COVID-19. A new Boston University School of Public Health (BUSPH) study in Lusaka, Zambia's capital, challenges the common belief that Africa somehow "dodged" the COVID-19 pandemic.

The findings indicate that low numbers of reported infections and deaths across Africa may simply be from lack of testing, with the coronavirus taking a terrible but invisible toll on the continent.

Published in The BMJ, the study found that at least 15% and as many as 19% of recently-deceased people arriving at Lusaka's main morgue over the summer had the coronavirus, peaking at 31% in July. Despite most having had COVID symptoms, few were tested before death.

"Our findings cast doubt on the assumption that COVID-19 somehow skipped Africa or has not impacted the continent as heavily," says study co-author Dr. Lawrence Mwananyanda, a BUSPH adjunct research assistant professor of global health based in Lusaka. "This study shows that with proper diagnostics and testing, we can begin to identify the scale of COVID-19 in African countries such as Zambia. I hope this study will encourage African governments to look closer at the rollout of COVID-19 testing, as well as empower Africans to take proactive steps--such as wearing masks, physically distancing, and skipping handshakes--to protect themselves from COVID-19."

The findings also have important implications for global health decision makers, says study corresponding author Dr. Christopher Gill, associate professor of global health at BUSPH. "We will only end the COVID-19 pandemic if we ensure equitable access to a vaccine. Without the full data picture of the spread of COVID-19 in Africa, it will be impossible to ensure COVID-19 vaccines can get to the people and places that need it most," he says.

An estimated 80% of people who die in Lusaka pass through the University Teaching Hospital morgue. From June to September, polymerase chain reaction tests on 364 recently-deceased people found the coronavirus in 70 of them. While the majority of COVID-19 deaths in the United States and Europe have been in older adults, most of the deceased people who tested positive in this study were under 60 years old, including seven children. The researchers say that such a high proportion of pediatric deaths was particularly surprising given how rare COVID-19 deaths in children have been reported elsewhere.

Of the 70 people who tested positive, the researchers sought information about the symptoms they had been experiencing leading up to their fatal illness. "In nearly all cases where we had those data, we found typical symptoms for COVID-19, yet only 6 had been tested before death," Gill says. And among the 75% of deaths that occurred outside of the hospital, none had been tested before they died.

However, detecting the coronavirus in any country is no easy feat, much less in countries with limited resources. The researchers say Zambia's Ministry of Health has been very proactive and supportive of this and other COVID studies. "They're really grateful that we can provide them this data, and they can make informed decisions moving forward with this epidemic," Mwananyanda says.

The researchers were well-positioned to track COVID in Zambia. With funding from the Bill & Melinda Gates Foundation, they have been conducting the Zambia Pertussis/RSV Infant Mortality Estimation Study (ZPRIME) at the University Teaching Hospital morgue in Lusaka since 2017. In that ongoing study, nurses and physicians' assistants approach families who have lost a child between the ages of four days and six months for consent to conduct a nasal swab of the infant, and to offer grief counseling.

"Building studies such as this from scratch can take time and resources that can be difficult in the time needed to tackle the COVID-19 pandemic. We invested a lot of time and money and human resources to building infrastructure that allowed for that extensive surveillance," says study co-author Rachel Pieciak a research fellow at BUSPH. "So, what we've done was repurpose ZPRIME study capacity to focus on enrolling all deaths across all ages and testing for COVID-19."

Other research teams in similar situations might also be able to pivot in this way, Pieciak says. While many governments don't have the resources to effectively track COVID rates, "there's a lot of research money in places where we're not seeing really great COVID data," she says. "I would encourage other groups like us to think creatively about the resources that they have available, and to contribute to this effort."

For their part, the research team's findings will help inform COVID-19 efforts not just in Zambia, but many other countries. "What this study tells us is that when we looked for COVID-19 in Zambia, we found it--and there are a whole lot of other countries where there's similar lack of testing," says study co-author Dr. William MacLeod, research associate professor of global health at BUSPH.

###

About the Boston University School of Public Health

Founded in 1976, the Boston University School of Public Health is one of the top five ranked private schools of public health in the world. It offers master's- and doctoral-level education in public health. The faculty in six departments conduct policy-changing public health research around the world, with the mission of improving the health of populations--especially the disadvantaged, underserved, and vulnerable--locally and globally.

Contact: Michelle Samuels, msamu@bu.edu

Pandemic got you down? A little nature could help

UNIVERSITY OF CONNECTICUT

Research News

 

IMAGE: A JAPANESE WORD MEANING 'FOREST-BATHING' SUGGESTS TIME IN NATURE CAN REDUCE STRESS; RESEARCHERS SAY THERE'S A LOT TO THAT. view more 

CREDIT: PETER MORENUS/UCONN PHOTO

Having trouble coping with COVID?

Go take a hike. Literally.

Researchers have long been aware of the positive impact of a connection with nature on psychological health and, according to a new study published in the journal Personality and Individual Differences, the pandemic hasn't decreased the power of nature to improve mental well-being.

"Thinking about the natural world in an interconnected and harmonious way corresponds to improved psychological health, no matter where you are," says Brian W. Haas, the lead author of the new study and an associate professor in the Behavioral and Brain Sciences Program at the University of Georgia.

Haas and his collaborators - Fumiko Hoeft, a professor of psychological sciences at UConn and director of UConn's Brain Imaging Research Center; and Kazufumi Omura, faculty of Education, Art and Science at Yamagata University in Japan - used a survey in America and Japan to measure worldviews on nature as well as how much the pandemic impacted people's lives, and their current psychological health.

The survey sought to gauge whether the participants had a worldview in harmony with nature - being in tune or connected with the natural world, or a worldview of mastery over nature - the belief that people have the ability to control the natural world. They also reported on their stress levels and were asked if the COVID-19 pandemic has affected them personally or impacted their employment or finances.

The researchers found that, while participants in general report greater stress levels during the pandemic, individuals with a harmony-with-nature worldview were coping better regardless of whether they lived in Japan or in the United States.

"Clearly there's great need for study as relates to the pandemic, not just now during COVID, but also of previous pandemics and for possible future pandemics," says Hoeft. "I feel like this is a really great lesson, and a moment for us to really appreciate that things like our relationship with nature do matter and make an impact on more tangible things, like our mental health, which we often forget."

The researchers found that the difference between the two cultures, however, became apparent when looking at individuals with a mastery-over-nature worldview.

"We found that the Americans who believed that humans are, and should be, the masters of the natural world did not tend to cope well during the pandemic," Haas says. "While this was not the case in Japan."

Rather, in Japan, having a mastery-over-nature worldview was not correlated with poor coping. The researchers suggest the difference might be rooted in the concept of naïve dialecticism - the acceptance or tolerance of contradiction.

"In other cultures outside of the United States, people tend to be more comfortable with contradiction; in other cultures, it is generally more accepted to possess conflicting ideas within your mind at the same time," Haas says. "But in the United States, it's not. We can apply this concept to nature and the current global pandemic. For instance, if I hold a view that I am the master of the natural world, and then a global pandemic happens, this is a clear natural disaster. If I believe that I am the master of the natural world, then surely I would never allow a natural disaster to happen. These concepts are inconsistent with one another, and a consequence of inconsistency is often negative mood."

While the study offers only a snapshot view of just two cultures, Haas believes other cultures would likely demonstrate a similar positive association with a harmony-with-nature worldviews, predicting that "it's likely a universal phenomenon."

Both Haas and Hoeft say that, in an increasingly virtual and technology driven world, taking a moment to appreciate nature has clear benefits regardless of where you live.

"In Japanese, there's this word called 'forest-bathing,'" Hoeft says. "It's basically when you go out into nature, and enjoy being surrounded by trees. It's usually for forests, but you go walking and it's supposed to refresh you. People often talk about how they went out 'forest bathing.' I love thinking about these kinds of old phrases - do they have some real impact or real scientific background in the end? And I think this is one of them where this really does have a connection. There is some scientific truth behind this."

"Think about taking a step away from Zoom for a moment and taking a walk and listening to the birds chirp," Haas says. "I mean, just the benefit of that, and understanding that we have a role in this natural world, and we're part of it. I think that's really intuitive and it's obvious, but I think it's also really, really important. We're showing very convincingly with empirical data that, during a very difficult time like we are in now, that it's important to do these things to maintain your psychological health."

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This study was supported with funding from a Global Research Collaboration Grant from the University of Georgia and a National Science Foundation grant, NSF #202937.

Wolves prefer to feed on the wild side

Research team studies feeding behavior of wild predators in Mongolia

UNIVERSITY OF GÖTTINGEN

Research News

 

IMAGE: TRACKS OF BEAR AND WOLF view more 

CREDIT: NINA TIRALLA

When there is a choice, wolves in Mongolia prefer to feed on wild animals rather than grazing livestock. This is the discovery by a research team from the University of Göttingen and the Senckenberg Museum Görlitz. Previous studies had shown that the diet of wolves in inland Central Asia consists mainly of grazing livestock, which could lead to increasing conflict between nomadic livestock herders and wild predatory animals like wolves. The study has been published in the journal Mammalian Biology.

Around three million people live in Mongolia, making it the most sparsely populated country in the world. In addition, there are more than 40 million grazing animals. These animals are not just a source of food but also the only source of income for more than half of the population. Livestock cultivation is leading to a massive change in Mongolia's landscape: areas close to nature are increasingly being converted into pastureland: in fact, one third of the country is now used for this purpose. This inevitably leads to conflict with the indigenous wild animals, especially large predators such as the wolf.

CAPTION

The Chentii Mountains in the north of Mongolia.

CREDIT

Nina Tiralla, University of Göttingen

Biologist and forest scientist Nina Tiralla from the University of Göttingen studied the feeding behaviour of wolves for her Master's thesis. Together with colleagues from the Senckenberg Museum, she analysed 137 wolf droppings collected during fieldwork in Mongolia between 2008 and 2012. "We were able to show that 89 percent of the wolves' diet consisted of wild ungulates, predominantly Siberian roe deer," says Tiralla. "The remaining 11 per cent consisted of small mammals such as hares or mice." Even remnants of insects and berries could be detected in the faeces - but there was no trace of farmed animals. "This was surprising for us because previous studies had shown grazing animals to be the main food source for wolves," says Tiralla.

The key difference could lie in the situation of the animals: unlike the earlier studies on Mongolian wolves, the samples examined in this study come from near-natural regions with high species diversity. "Although there is also a supply of grazing animals here, the wolves seem to prefer wild animals such as the Siberian roe deer as prey, possibly because they are easier and less dangerous to hunt," the authors explain. They conclude that if wolves live in a near-natural and species-rich landscape with sufficient prey, they pose only a very low threat to grazing livestock. This could apply not only in Mongolia, but in principle also to other countries.

CAPTION

Nina Tiralla from the University of Göttingen follows a wolf trail in Mongolia.

CREDIT

Nina Tiralla, University of Göttingen

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Original publication: Nina Tiralla, Maika Holzapfel, Hermann Ansorge (2021). Feeding ecology of the wolf (Canis lupus) in a near-natural ecosystem in Mongolia. Mammalian Biology 101: 83-89. https://doi.org/10.1007/s42991-020-00093-z

Contact: Nina Tiralla
University of Göttingen
Faculty of Forest Sciences and Forest Ecology
Bioclimatology Group
Büsgenweg 2, 37077 Göttingen, Germany
Email: ntirall1@gwdg.de
http://www.uni-goettingen.de/en/197704.html

Spotted lanternfly: Research accelerates in effort to contain invasive pest

New collection showcases growing body of knowledge on spotted lanternfly biology and management

ENTOMOLOGICAL SOCIETY OF AMERICA

Research News

 

IMAGE: THE SPOTTED LANTERNFLY (LYCORMA DELICATULA) IS A TREEHOPPER NATIVE TO ASIA BUT WAS DISCOVERED IN PENNSYLVANIA IN 2014, AND IT HAS SINCE SPREAD TO FIVE OTHER NORTHEASTERN STATES. ITS PRIMARY... view more 

CREDIT: STEPHEN AUSMUS, U.S. DEPARTMENT OF AGRICULTURE-AGRICULTURAL RESEARCH SERVICE, PUBLIC DOMAIN

Annapolis, MD; February 17, 2021--When the invasive spotted lanternfly arrived in the United States in 2014, it was immediately recognized for the threat it posed to native plants and crops. A community of researchers and experts in science, agriculture, and government sprang into action to respond, improving our chances for containing the pest and curbing its potential for damage.

While the effort continues, a new collection curated by the Entomological Society of America's family of journals showcases the growing body of research that is helping us understand the spotted lanternfly's biology and how to contain it. The collection features 25 articles published in ESA journals since 2015, with 16 of them new additions since June 2020.

The spotted lanternfly (Lycorma delicatula) is a treehopper native to Asia but was discovered in Pennsylvania in 2014, and it has since spread to five other northeastern states. Its primary host is tree of heaven (Ailanthus altissima), but it is known to feed on more than 100 types of plants--mostly trees, shrubs, and stout vines. Valuable crops the spotted lanternfly can damage include grapes, apples, and peaches, as well as hardwood trees. One study of the lanternfly's potential range in the U.S., based on environmental and climatic conditions, suggests most of New England and the mid-Atlantic states as well as parts of the central U.S. and Pacific Northwest are vulnerable to establishment of the spotted lanternfly if it finds its way there.

Melody Keena, Ph.D., research entomologist at the U.S. Forest Service, is co-editor-in-chief of the ESA journal Environmental Entomology and compiled the collection on spotted lanternfly. Like many, Keena was struck by the insect's potential when she first learned about it. "I was surprised because it is so much bigger than the treehoppers that are native. I was also surprised by the large numbers congregating on single trees," she says.

Early on, the U.S. Department of Agriculture's Animal Plant Health Inspection Service and the state of Pennsylvania led the charge, says Keena, while more states and groups have joined in as the spotted lanternfly has spread.

"Both federal and university groups--with Pennsylvania State University taking the early lead--have developed a lot of knowledge and tools rapidly for dealing with this pest, as this collection demonstrates," Keena says.

Engaging the public has been critical as well.

"The public has taken an interest in it because of the major nuisance the adults are in the fall, with all the honey dew the lanternflies produce and black sooty mold that grows on it," Keena says. "They are willing to help in any way they can, like removing its egg masses or smashing adults they find or allowing researchers to use their property."

The research collection showcases progress made so far, as continued awareness and research will be necessary to slow the spotted lanternfly's spread.

"Multiple tools for trapping and killing spotted lanternfly have been developed but still need improvement, especially for adults. Biological control organisms have been found and are being evaluated. Prospects for managing it are good," says Keena. "We don't yet know how far it will successfully be able to spread, but there are indications that it may have some climatic limitations. Current work to understand how humans are aiding its spread, and how to cut off those avenues, is underway."

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The ESA spotted lanternfly collection is available at http://www.academic.oup.com/ee/pages/research-on-spotted-lanternfly, featuring 25 articles published across the ESA family of journals. Several articles in the collection have also been featured in accompanying posts at the Entomology Today blog, available at http://www.entomologytoday.org/tag/slf-collection.

CONTACT: Joe Rominiecki, jrominiecki@entsoc.org, 301-731-4535 x3009

ABOUT: ESA is the largest organization in the world serving the professional and scientific needs of entomologists and people in related disciplines. Founded in 1889, ESA today has more than 7,000 members affiliated with educational institutions, health agencies, private industry, and government. Headquartered in Annapolis, Maryland, the Society stands ready as a non-partisan scientific and educational resource for all insect-related topics. ESA publishes eight internationally acclaimed journals that provide unsurpassed coverage of the broad science of entomology, as well as the quarterly magazine American Entomologist. For more information, visit http://www.entsoc.org and http://www.insectscience.org.