Friday, April 15, 2022

The shape of things to come: tropical birds are changing because of us

A new study finds that human activity has led to changes in the body shapes and diets of birds on the tropical island of Hainan

Peer-Reviewed Publication

XI'AN JIAOTONG-LIVERPOOL UNIVERSITY

Vinous-throated parrotbill — IMAGE: GENERALIST BIRD SPECIES, WHICH CAN EAT A VARIETY OF FOODS, THRIVE IN HAINAN. view more
CREDIT: @EMILIOPNUNEZ

Hainan has a unique tropical environment with abundant biodiversity and is home to over 400 species of birds. The island in southern China has experienced fast economic development changes over the past 20 years, and although efforts have been taken to protect Hainan’s biodiversity, the full impact of the changes is not clear.

A new study has shown that human activity on Hainan has led to biotic homogenisation in birds, with communities and species becoming increasingly similar, for example, in their body shape and diet.

The research findings were recently published in the journal Conservation Biology.

Tipping the scales

The research team from Xi’an Jiaotong-Liverpool University, South China Normal University, and Guangdong Academy of Agricultural Sciences analysed the local climate, land and economic changes around Hainan between two time periods, separated by 15 years, to understand the effects of urban growth and conservation on biodiversity.

Their results suggest that large-scale economic and land-use changes affect many aspects of biodiversity, such as decreasing species richness and species variability - biotic homogenisation. Human activity also appears to cause Hainan’s forest birds to be out-competed by more human-tolerant species.

Additionally, the study shows that the effects of measures taken to protect Hainan’s unique ecosystem are more complex than previously thought. Environmental protection in urban areas positively influences biodiversity; however, similar efforts in rural areas that are initially species-rich result in less biodiversity. This dual effect results in no significant net loss in biodiversity.

Dr Emilio Pagani-Núñez, the first author of the study, says: “We found that extreme negative effects on biodiversity were averted by environmental legislation. However, we also recorded an increasing similarity between communities around the island and complex effects of human activities on biodiversity.

“We are showing that there is hope for biodiversity, that economic growth and enhanced biodiversity conservation are possible. However, a price will be paid, and it is our duty to prevent such negative effects by developing targeted policies on especially diverse or sensitive ecosystems and communities.”

Maintaining balance

Dr Pagani-Núñez continues: “Biodiversity loss and biotic homogenisation are pervasive trends in the Anthropocene.

“We are witnessing the sixth mass extinction, which means a simplification of natural communities only comparable to previous traumatic events that considerably reduced worldwide biodiversity. If these negative effects of human activities do not decrease, it is highly likely that natural communities will not have the chance to recover.

“Governments and companies need to invest more in biodiversity conservation and integrate biodiversity conservation into economic development plans to create landscapes for both biodiversity and people,” says Dr Pagani-Núñez.

Dr Pagani-Núñez hopes that further research in the related fields of this subject can be carried out in the future, extending their research to include amphibians and mammals across larger geographical areas. A better understanding of the effects of urban growth on biodiversity will help coordinate the balance between environmental protection and economic development and provide more guidance for sustainable development.

JOURNAL

Conservation Biology

DOI

10.1111/cobi.13912

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Trade-offs between economic development and biodiversity conservation on a tropical island

Communication between physicians, patients regarding electronic cigarette use

JAMA Network Open

Peer-Reviewed Publication

JAMA NETWORK

What The Study Did: This survey study that included more than 2,000 physicians assessed what they communicate and recommend to their patients regarding the use of e-cigarettes.

Authors: Cristine D. Delnevo, Ph.D., M.P.H., of Rutgers University in New Brunswick, New Jersey, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2022.6692)

Editor’s Note: Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

# # #

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About JAMA Network Open: JAMA Network Open is the new online-only open access general medical journal from the JAMA Network. On weekdays, the journal publishes peer-reviewed clinical research and commentary in more than 40 medical and health subject areas. Every article is free online from the day of publication.

JOURNAL

JAMA Network Open

Many physicians have misconceptions about e-cigarettes

Most doctors want more evidence on safety and effectiveness before recommending them as an alternative to cigarette smoking

Peer-Reviewed Publication

RUTGERS UNIVERSITY

Many physicians incorrectly believe all tobacco products are equally harmful and thus are less likely to recommend e-cigarettes for people seeking to quit smoking or those being treated for a tobacco-caused disease, according to a Rutgers study.

About 480,000 people die each year in the United States from smoking tobacco. Although the Food and Drug Administration has not approved e-cigarettes as a cessation device, many people ask their physicians about using them as an alternative to tobacco cigarettes or as a way to help them stop smoking. E-cigarettes use a heated liquid containing nicotine.

“As the evidence grows showing e-cigarettes as potentially effective for smoking cessation, they may play a pivotal role in reducing use of cigarettes and subsequently tobacco-caused disease,” said study author Michael Steinberg, medical director of the Rutgers Tobacco Dependence Program at the Center for Tobacco Studies and division chief in the Department of Medicine at the Rutgers Robert Wood Johnson Medical School. “It’s important to understand physicians’ perspectives on e-cigarettes as a means for harm reduction.”

The study, published in JAMA Network Open, asked 2,058 U.S. physicians in 2018 and again in 2019 about their communication with patients about e-cigarettes. The researchers asked how they would advise two different patients who wanted to quit smoking: a young woman who is a lighter smoker and had not yet tried to quit and an older man who smoked heavily and had tried to quit many times using different methods.

The study found that physicians were significantly more likely to recommend e-cigarettes for the heavy smoker while recommending FDA-approved medications, like nicotine gum or lozenges, for the light smoker. Nearly 70 percent of the physicians reported that patients have asked them about e-cigarettes, and one-third said they were asked in the past 30 days. More than 60 percent of the doctors incorrectly believed that all tobacco products are equally harmful.

“These findings show it is critical to address physicians’ misperceptions and educate them on e-cigarettes’ efficacy, particularly correcting their misperceptions that all tobacco products are equally harmful, as opposed to the fact that combusted tobacco is by far the most dangerous,” said lead author Cristine Delnevo, director of the Rutgers Center for Tobacco Studies and professor of Health Behavior, Society and Policy in the Rutgers School of Public Health.

The study also found that pulmonologists, cardiologists and physicians who used the U.S. Public Health Service Clinical Practice Guidelines for treating tobacco use and dependence were more likely to recommend e-cigarettes to patients as were those who endorsed a harm-reduction perspective and had themselves smoked cigarettes. Physicians were also more likely to recommend e-cigarettes, however, if a patient asked about them first.

Other Rutgers authors in the study included Michelle Jeong, Arjun Teotia, Michelle M. Bover Manderski, Binu Singh, Mary Hrywna and Olivia A. Wackowski.

JOURNAL

JAMA Network Open

DOI

10.1001/jamanetworkopen.2022.6692

METHOD OF RESEARCH

Survey

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Communication Between US Physicians and Patients Regarding Electronic Cigarette Use

ARTICLE PUBLICATION DATE

15-Apr-2022

COI STATEMENT

Dr Delnevo reported receiving grants from National Institutes of Health/National Cancer Institute (NIH/NCI) work funded by R01 CA190444 during the conduct of the study and being a voting member of the US Food and Drug Administration Tobacco Product Scientific Advisory Committee. Dr Jeong reported receiving grants from the NCI during the conduct of the study. Dr Bover Manderski reported receiving a grant from NCI (R01CA190444) during the conduct of the study. Drs Hrywna,Wackowski, and Steinberg reported receiving grants from the NCI during the conduct of the study.

Smoking reduces wealth’s tendency to increase life expectancy

Smoking dominates other factors, including amount of wealth, in shortening lifespan

Peer-Reviewed Publication

UNIVERSITY OF CALIFORNIA - RIVERSIDE

Smoking dominates other factors, including amount of wealth, in shortening lifespan, reports a study by researchers at Georgetown University and the University of California, Riverside.

“Our results suggest that even if wealth has a causal effect on mortality, it cannot compete with the impact of smoking. If you want to live longer, you better avoid the cancer sticks,” said corresponding author Dana Glei, a senior research investigator at Georgetown University’s Center for Population and Health.

The new study finds that the percentage of Americans surviving from age 65 to 85 was 19 percentage points higher for someone with at least $300,000 in wealth than for those with no assets. But there was a 37 percentage point difference between those who never smoked and current smokers. Due to how the data was collected, wealth was measured in 1995 dollars. $300,000 is the equivalent of $558,000 today.

The wealth-related disparity in mortality was larger than the disparities by education, occupation, income, or childhood socioeconomic status. But smoking made the greatest difference among all factors.

"Our finding further confirmed that smoking shortens our lives and that abstaining from smoking might be cheaper and more effective for living longer,” said Chioun Lee, an assistant professor of sociology at UC Riverside.

Glei, along with Lee and Maxine Weinstein, a professor at Georgetown University, used data from 6,320 participants in the Midlife in the United States, or MIDUS, study funded by the National Institute on Aging to examine the effects of childhood socioeconomic status, education, occupation, income, wealth, and smoking history on mortality for adults aged 20-92 years old.

In fully adjusted models—which also controlled for age, sex, race, marital status, health insurance coverage, employment status, and numerous health-related measures—the researchers found that wealth outpaced all other measures of socioeconomic status associated with living past age 65. Mortality declined at higher levels of wealth, but wealth above $500,000 (in 1995 dollars) yielded no further mortality benefit. This amount is the equivalent of more than $925,000 today.

"We already know having a good education, a well-paid job, and extra savings are critical factors that help us live longer and stay healthier. Among education, occupation, income, and wealth, we found that wealth seems to be most important for longevity. However, beyond a certain amount, additional wealth may not yield extra years of life,” said Lee.

For smokers, however, the picture was much grimmer. Above age 65, the mortality rate among current smokers was three times higher than never-smokers. Former smokers had significantly lower mortality than current smokers, but slightly higher mortality than never-smokers.

“Health care practitioners cannot modify their patient’s wealth, but they should continue to discourage smoking. Wealth may be associated with longevity, but just don’t smoke,” said Glei.

The open-access paper, “Assessment of mortality disparities by wealth relative to other measures of socioeconomic status among us adults,” is published in Jama Network Open and available here.

JOURNAL

JAMA Network Open

DOI

10.1001/jamanetworkopen.2022.6547

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Assessment of Mortality Disparities by Wealth Relative to Other Measures of Socioeconomic Status Among US Adults

ARTICLE PUBLICATION DATE

8-Apr-2022

COI STATEMENT

Dr Glei reported receiving salary via a grant from the National Institute on Aging (NIA) during the conduct of the study. Dr Lee reported receiving a grant from the NIA during the conduct of the study. Dr Weinstein reported receiving a grant from the NIA during the conduct of the study.

New study shows increase in black lung disease in coal miners

Provides rationale for the mine safety and health administration to develop a more protective occupational standard for silica.

Peer-Reviewed Publication

AMERICAN THORACIC SOCIETY

April 14, 2022 – Higher levels of silica dust can be found in the lung tissue of contemporary coal miners compared to the lung tissue in previous generations of coal miners, according to a new study in the Annals of the American Thoracic Society. The study helps explain the recent increase in severe pneumoconiosis – often referred to as black lung disease – concentrated in central Appalachia (West Virginia, Virginia and Kentucky) miners.

The study, “Pathology and Mineralogy Demonstrate Respirable Crystalline Silica is a Major Cause of Severe Pneumoconiosis in U.S. Coal Miners”, is unique in that it compares the lung tissue of the current generation of coal miners to lung tissue collected from miners from previous generations.

Silica is a naturally occurring substance that is ubiquitous in the earth’s mantle. Over ninety percent of rocks contain silica. While safe in rock formations, breathing in silica dust is highly toxic and prolonged exposure to silica dust can lead to severe lung disease.

From 1970 to 2005, the rate of black lung cases among coal miners had been declining, largely due to improved occupational health practices required by federal regulations. However, since 2005, black lung cases in general have seen a three-fold increase and long-term coal miners have seen a 10-fold increase in black lung cases. The study conducted by Robert Cohen, MD – director of the Mining Education and Research Center at the University of Illinois, Chicago (UIC) – and colleagues provides strong evidence that silica is a major cause for the previously unexplained rise in black lung cases.

The change in silica exposure among coal miners is likely explained by changing mining practices initially adopted in the 1950s, as the coal industry started using powerful mechanized coal extraction devices. The powerful coal mining machinery enabled companies to extract large swaths of rock above and below the coal seams, which is much easier than mining focused on narrow veins of coal. This resulted in the generation of more silica dust.

In addition to providing an explanation, the study helps mine owners and federal regulators to better understand steps that must be taken to prevent future cases of black lung. “Reducing coal miner exposure to silica dust is essential to prevent further black lung cases,” said Dr. Cohen, clinical professor of environmental and occupational health sciences at UIC. “This study provides clear, actionable evidence for the Mine Safety and Health Administration (MSHA) to establish specific silica dust exposure limits to protect coal miners from the known dangers of black lung disease.”

The current MSHA silica standard of 100 ug/m3 was established in 1969 and has not been revised since. By contrast, the Occupational Safety and Health Administration has established a much more protective silica exposure limit of 50 ug/m3 for other non-mining occupations.

JOURNAL

Annals of the American Thoracic Society

METHOD OF RESEARCH

Systematic review

SUBJECT OF RESEARCH

Human tissue samples

DOD Awards $297,831 to study effects of toxic pollutants on airway pathology

A biomedical engineering researcher will develop a combined “nasal airway and lung-on-a-chip” platform to mimic the upper and lower respiratory system

Grant and Award Announcement

UNIVERSITY OF ARKANSAS

The Department of Defense awarded $297,831 to Kartik Balachandran, associate professor of biomedical engineering at the U of A, to study the effects of particulate matter pollution on the nasal airway and lung interface.

Balachandran will create the first in vitro benchtop system to incorporate both the upper and lower respiratory systems into a single model.

Over the two-year term of the grant, Balachandran will create and validate a novel airway-lung-on-a-chip, or AirLOC, system engineered from human cells. This will incorporate a multilayered, cell culture platform that mimics both normal and asthmatic nasal and lung epithelia – the tissue that covers all organs and body surfaces. These 3-D chips can replicate several aspects of human physiology, and, according to Balachandran, “can recreate complex organ functions, tissue-barrier properties, parenchymal tissue function and multi-organ interactions.”

AirLOCs will be exposed to particulate matter of different sizes for differing durations. Both air flow and blood flow will be simulated as well as the connection from the nasal airway compartment to the bronchial airway compartment.

The association between respiratory illness and exposure to particulate matter is well documented. Particulate matter can take the form of anything from dust storms to vehicular exhaust. Larger particles tend to lodge in the upper respiratory system and lungs while smaller particles can penetrate deeper into the lung’s alveoli sacs. The accumulation of particulate matter can lead to increased risk of chronic obstructive pulmonary disease, as well as asthma, allergic rhinitis and other respiratory infections.

“We are very excited to receive this grant from the DOD,” Balachandran said. “We will study the pathological effects of particulate matter in this project. In the future, we hope that this AirLOC model can be used to study other diseases and problems that affect the human upper and lower respiratory systems.”

Organs on a chip are something of specialty for Balachandran, who is also developing a chip that simulates the aortic valve tissue to study the impact of SARS-COV-2 on heart pathology.

International OK shapes public perceptions of drone warfare

Peer-Reviewed Publication

CORNELL UNIVERSITY

ITHACA, N.Y. -- Armed drone strikes earn more public support and legitimacy when they have international approval from organizations such as the United Nations, according to a survey conducted by a team of Cornell researchers.

Drones that carry weapons are increasingly employed as counterterrorism tools, but nations use and constrain strikes differently. France, for example, submits its strikes to the U.N. for approval; the U.S. typically does not.

This difference matters when it comes to public support and perceptions of legitimacy, according to doctoral students Paul Lushenko and Shyam Raman, and Sarah Kreps, the John L. Wetherill Professor of Government in the College of Arts and Sciences and a professor in the Cornell Jeb E. Brooks School of Public Policy.

The researchers cite as examples two drone strikes in 2021. France used a drone to kill Adnan al-Sahrawi, the Islamic State’s leader in western Africa. Soon after, the U.S. used drones to kill two al-Qaida leaders in Syria.

While the weapons were similar, the approaches were not. France went to the U.N. in advance to secure backing; the U.S. acted unilaterally.

To find out which approach has greater public support and legitimacy, the researchers conducted a survey of a representative sample of 1,800 respondents in France and the U.S. The results were statistically significant and showed greater cross-national support and legitimacy when drone strikes had international approval and were perceived to comply with international law.

Respondents’ homeland did play a factor, however. French respondents found any unilateral strike by their country or another to be less legitimate. Americans perceived unilateral strikes by their own country as more legitimate and more worthy of support. Together, these results suggest Americans and French citizens endorse unique patterns of drone warfare.

The researchers show that the “French model” of drone warfare is based partly on international authorization, which is the case for French counterterrorism strikes in western Africa.

“Despite the proliferation of armed drones globally, we lack an understanding of public attitudes for strikes, especially in a cross-national context,” Lushenko said. “Our research shows that the public’s perceptions for legitimate strikes are not merely a function of the target. The perceived legitimacy of strikes can be shaped by who uses drones and how they are constrained, suggesting that international authorization through the U.N. has important implications in the battle for public opinion.”

Lushenko is a Ph.D. candidate in the field of international relations, and a General Andrew Jackson Goodpaster Scholar. Raman is a PhD student in the field of policy analysis and management. An article about their research, “Multilateralism and Public Support for Drone Strikes,” was published in the April edition of Research and Politics.

-30-

DOI

10.1177/20531680221093433

National Cheng Kung University researchers present new solution for wastewater remediation

The new eco-friendly nanocomposite hydrogels can be reused many times to adsorb ionic pollutants from wastewater

Peer-Reviewed Publication

CACTUS COMMUNICATIONS

Synthetic dyes are used across a wide variety of industries and constitute a serious concern when it comes to water pollution. These dyes are not only toxic, but they also persist in the environment for a long time without degradation. Most approaches to removing synthetic dyes from water are based on adsorption—a phenomenon where a chemical molecule becomes bonded to the surface of a substrate called an adsorbent. Carbon-based systems are commonly adopted as adsorbents, but they are limited by the need for a safe disposal route for the used adsorbent and the inability to reuse the material. Many polymers have also been investigated as adsorbents, but they show poor water solubility and stability.

Recently, an international team of researchers—including Prof. Wei-Hsin Chen of National Cheng Kung University, Taiwan—have developed a novel eco-friendly and reusable nanocomposite-based solution for removing toxic dyes from wastewater. The paper describing the study was made available online on 31 July 2021 and was published in Volume 421 of the Journal of Hazardous Materials on 5 January 2022.

“Carboxymethyl cellulose (CMC) is an inexpensive cellulose derivative that is easy to produce, eco-friendly, and biocompatible. But it has relatively poor thermal and mechanical properties. In our study, we successfully improved CMC by combining it with polyacrylic acid (PAA). The prepared materials can be efficient adsorbents for ionic pollutants in wastewater treatment.” says Prof. Chen.

CMC is a well-characterized, inexpensive polymer derived from natural cellulose, an abundant polymer found in plants and microalgae such as Chlorella sp. In this study, the researchers combined CMC with PAA—a water-loving, non-toxic and safe polymer—and loaded the resultant hydrogels with graphene oxide. Finally, by subjecting these hydrogels to repeated cycles of washing and freeze-drying, they converted the hydrogels into ‘aerogels,’ which are porous solid networks containing air pockets that have high adsorptive capacities.

The research team then characterized the aerogels using field emission scanning electron microscopy and laboratory techniques and found that different levels of graphene oxide created different sized pores within the aerogel. They found that the addition of graphene oxide increased the specific surface area and thermal stability of the nanocomposite hydrogels. They also saw that the pore size of the hydrogels decreased with increasing concentrations of graphene oxide. Moreover, the aerogel developed in this study had an adsorption capacity of 138 mg/g of methylene blue after 250 min—which is among the highest methylene blue adsorption capacities reported in literature. According to Prof. Chen, “The adsorbent developed in this study is both environmentally friendly and cost-effective, indicating its high application potential for the removal of cationic dyes from wastewater.”

Finally, the researchers saw that the new hydrogels retained about 90% of their adsorption capacity even after nine cycles of use and regeneration.

They then wanted to investigate the mechanism behind the high adsorption capacity of the hydrogels, so they performed density functional theory (DFT) simulations. The results of their simulations suggested that the methylene blue bound more strongly to graphene oxide than to CMC or PAA. They also saw that the adsorption of methylene blue on the graphene oxide in the nanocomposite took place via pi-electron bonding, hydrogen bonding, and electrostatic interactions.

The nanocomposite hydrogels fabricated in this study provide an eco-friendly, stable, efficient, and reusable adsorbent material to remove synthetic dyes from wastewater and provide improvements to both environment and human health.

***

Reference

DOI: https://doi.org/10.1016/j.jhazmat.2021.126752

Authors: Hadi Hosseini a, Abbas Zirakjou b, David Julian McClements c, Vahabodin Goodarzi d,* , Wei-Hsin Chen e,f,g

Affiliations

a University of Mazandaran, Iran

b University of Tehran, Iran

c University of Massachusetts, USA

d Baqiyatallah University of Medical Sciences, Iran

e National Cheng Kung University, Taiwan

f Tunghai University, Taiwan

g National Chin-Yi University of Technology, Taiwan

About Prof. Wei-Hsin Chen

Wei-Hsin Chen is a Distinguished Professor at the Department of Aeronautics and Astronautics at the National Cheng Kung University, Taiwan. His research interests are aerosols, bioenergy, clean energy, and hydrogen energy. Prof. Chen was previously associated with Fooyin University, National Taiwan Ocean University, and the National University of Tainan. He has authored over 400 research papers in renowned journals and has been cited approximately 18,000 times. He has been affiliated with the National Cheng Kung University since 2013.

JOURNAL

Journal of Hazardous Materials

DOI

10.1016/j.jhazmat.2021.126752

ARTICLE TITLE

Removal of methylene blue from wastewater using ternary nanocomposite aerogel systems: Carboxymethyl cellulose grafted by polyacrylic acid and decorated with graphene oxide

ARTICLE PUBLICATION DATE

8-Apr-2022

Rain, floods and green infrastructure: Are cities mitigating the hazards equitably?

New research overlays sociodemographic, green infrastructure and stormwater flood risk data to assess equitable distribution of green infrastructure

Peer-Reviewed Publication

PORTLAND STATE UNIVERSITY

As cities grow, the area of impervious surfaces they cover grows. In cities across the US, roads, rooftops, parking lots, sidewalks and driveways increased by an average of 326,000 hectares per year between 2012 and 2017.

When it rains, stormwater gathers on these surfaces or flows into gutters, storm drains and sewer systems. However, extreme precipitation events can overwhelm a city's capacity to transport stormwater, resulting in urban floods. The introduction of green infrastructures (GI), such as bioswales with permeable surfaces, has provided municipalities with a new tool to manage flood risk associated with rainfall. Cities including Portland, Phoenix and Atlanta have developed plans and invested in implementing GI to mitigate the risk of floods.

New research from Portland State University combines demographic data with the distribution of GI and geographic areas prone to rainwater flooding in Portland, Phoenix and Atlanta and asks whether these cities are equitably building GI to mitigate flood risks.

The paper, "Urban flood risk and green infrastructure: Who is exposed to risk and who benefits from investment? A case study of three US cities," appears in Landscape and Urban Planning.

According to the paper's lead author, Arun Pallathadka, a Ph.D. student in the Earth, Environment and Society program at Portland State, the research team found that the placement of GI in each of the cities inconsistently overlapped with areas prone to rainwater flooding, and non-white and low-income populations were more vulnerable to flood risk. Portland and Phoenix have increased investments in GI in neighborhoods with higher populations of non-white and low-income residents, marking a transition to more equitable flood risk management. In Atlanta, the risk of rainwater flooding was relatively low for non-white and low-income residents, though there was a substantial disparity in GI coverage.

"Flooding is the costliest natural hazard," Pallathadka said. "But when we talk about flooding, the focus is often on the floodplain, on rivers. But with climate change, we're expecting an increase in flooding associated with rainfall events. We wanted to know where the hotspots in cities are associated with a risk of flooding from rain, who are the people living in those communities, and where are cities placing infrastructure to help reduce the hazards."

In addition to the spatial, temporal and demographic analysis, the research team, which includes Heejun Chang, a professor of geography at Portland State and Jason Sauer and Nancy Grimm of Arizona State University, developed that can be used by researchers, city planners and policymakers to categorize neighborhood risk levels. Cities can use the tool to help guide investments in GI to neighborhoods most at risk of flooding from rainfall events. A conceptual framework for understanding the distribution and implications of urban pluvial flood risk and green infrastructure (GI) in urban communities.

The methods deployed by the team provide cities with a novel approach to assessing the need for GI in neighborhoods prone to flooding associated with rainwater while also planning for the equitable distribution of those resources as they move ahead under the threat of increasing extreme precipitation events associated with a warming planet.

JOURNAL

Landscape and Urban Planning

DOI

10.1016/j.landurbplan.2022.104417

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Urban flood risk and green infrastructure: Who is exposed to risk and who benefits from investment? A case study of three U.S. Cities

Amplification of light within aerosol particles accelerates photochemical reactions

Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

Amplification of light in atmospheric aerosol particles can affect their photochemistry, substantially accelerating sunlight-driven in-particle photochemical reactions, which are major contributors to the degradation and oxidation of matter in these particles. Although theorized, the new study provides direct evidence that the influence of optical confinement (OC) can create spatial structuring of the light intensity inside the particles and result in variations of photochemical rates. Given the newfound importance of the phenomenon on aerosol particle photochemistry, incorporating the effects of OC into atmospheric aerosol models could improve their ability to predict global chemistry and climate. Although tiny, atmospheric aerosol particles – suspensions of fine solid particles or liquid droplets in air – have a large influence on climate and air quality, and are key components of global atmospheric models. Photochemical reactions driven by aerosol exposure to sunlight are central to atmospheric chemistry, including the creation and control of pollutants and climate-influencing gases. Here, Pablo Corral Arroyo and colleagues report the effect of OC on the photochemical reactions within aerosol particles. While previous research has predicted the effects of OC on aerosol particle photochemistry, direct observation of the phenomenon has remained elusive. Using a combination of x-ray spectromicroscopic imaging and modeling of single iron(III)-citrate particles (a photochemically degrading aerosol), Corral Arroyo et al. show that aerosol particles can act as resonators for incoming solar radiation, resulting in an overall amplification and spatial structuring of light within the particles, thereby accelerating in-particle photochemistry. Using the findings, the authors predict that this could speed up photochemical reactions by a factor of two to three for most classes of atmospheric aerosol particles.

JOURNAL

Science

DOI

10.1126/science.abm7915

ARTICLE TITLE

Amplification of light within aerosol particles accelerates in-particle photochemistry

ARTICLE PUBLICATION DATE

15-Apr-2022

Light amplification accelerates chemical reactions in aerosols

Peer-Reviewed Publication

ETH ZURICH

Liquid droplets and very fine particles can trap light – similar to how light can be caught between two mirrors. As a result, the intensity of the light inside them is amplified. This also happens in very fine water droplets and solid particles in our atmosphere, i.e. aerosols. Using modern X-ray microscopy, chemists at ETH Zurich and the Paul Scherrer Institute (PSI) have now investigated how light amplification affects photochemical processes that take place in the aerosols. They were able to demonstrate that light amplification causes these chemical processes to be two to three times faster on average than they would be without this effect.

Using the Swiss Light Source at the PSI, the researchers studied aerosols consisting of tiny particles of iron(III) citrate. Exposure to light reduces this compound to iron(II) citrate. X-ray microscopy makes it possible to distinguish areas within the aerosol particles composed of iron(III) citrate from those made up of iron(II) citrate down to a precision of 25 nanometres. In this way, the scientists were able to observe and map in high resolution the temporal sequence of this photochemical reaction in individual aerosol particles.

Decay upon exposure to light

“For us, iron(III) citrate was a representative compound that was easy to study with our method,” says Pablo Corral Arroyo, a postdoc in the group headed by ETH Professor Ruth Signorell and a lead author of the study. Iron(III) citrate stands in for a whole range of other chemical compounds that can occur in the aerosols of the atmosphere. Many organic and inorganic compounds are light-sensitive, and when exposed to light, they can break down into smaller molecules, which can be gaseous and therefore escape. “The aerosol particles lose mass in this way, changing their properties,” Signorell explains. Among other things, they scatter sunlight differently, which affects weather and climate phenomena. In addition, their characteristics as condensation nuclei in cloud formation change.

As such, the results also have an effect on climate research. “Current computer models of global atmospheric chemistry don’t yet take this light amplification effect into account,” ETH Professor Signorell says. The researchers suggest incorporating the effect into these models in future.

Non-uniform reaction times in the particles

Now precisely mapped and quantified, the light amplification in the particles comes about through resonance effects. The light intensity is greatest on the side of the particle opposite the one the light is shining on. “In this hotspot, photochemical reactions are up to ten times faster than they would be without the resonance effect,” says Corral Arroyo. Averaged over the entire particle, this gives an acceleration by the above-mentioned factor of two to three. Photochemical reactions in the atmosphere usually last several hours or even days.

Using the data from their experiment, the researchers were able to create a computer model to estimate the effect on a range of other photochemical reactions of typical aerosols in the atmosphere. It turned out that the effect does not pertain just to iron(III) citrate particles, but all aerosols – particles or droplets – made of compounds that can react with light. And these reactions are also two to three times faster on average.

JOURNAL

Science

DOI

10.1126/science.abm7915

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Amplification of light within aerosol particles accelerates in-particle photochemistry

Moving away from genetic continental ancestry categories in research and medicine

Reports and Proceedings

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

In a Policy Forum, Anna Lewis and colleagues argue that, for researchers and others who want to invoke genetic ancestry, there is a scientific and ethical imperative to move away from continental ancestry categories and to instead embrace a view of genetic ancestry that reflects continuous variation and historical depth. Such change is a “prerequisite to any research that looks for connections between genetics and health disparities,” the authors say. A continued reliance on continental ancestry categories risks exacerbating medical stereotypes about individuals and groups, contributing to health disparities rather than addressing them, and perpetuating (mis)understandings of race as biological, they add. Many research institutions are reconsidering their use of race as a biological variable and, instead, turning to concepts from genetics to capture differences between groups of humans. Genetic ancestry – a dominant description of genetic ancestry associated with continents as meaningful groupings – is one of the main proposed alternatives. However, the increasing dominance of the use of continental ancestry categories, such as “African ancestry” or “European ancestry,” has led to problematic ethical issues. Here, Lewis et al. highlight the ethical concerns surrounding the continued use of continental ancestry to group individuals. They argue instead for the widespread adoption of a more complex approach to genetic ancestry – a multidimensional, continuous, and category-free concept that reflects our historical depth and the total spectrum of human variation. Lewis et al. provide a roadmap to achieving this goal, a journey that will require a systems-level change, including new tools, methodologies, and data structures, and a fuller understanding of how and why different fields use and apply the concept of ancestry. “Science is reductive, and a model that uses simple continental categories has been useful in starting the process of understanding human genetic diversity,” write Lewis et al. “But all models have their legitimate domains of application and limits, and a much more complex set of models should now be the norm across a wide variety of use cases.”

JOURNAL

Science

DOI

10.1126/science.abm7530

ARTICLE TITLE

Getting genetic ancestry right for science and society

ARTICLE PUBLICATION DATE

15-Apr-2022