New research reveals how hurricane Lane brought fire and rain to Hawaiian islands

UNIVERSITY OF HAWAII AT MANOA

 

IMAGE: TWO VIEWS FROM THE RAINBOW FALLS OVERLOOK NEAR HILO, HAWAI?I--LEFT SHOWS TYPICAL FLOW; RIGHT SHOWS THE EARLY IMPACT OF HURRICANE. view more 

CREDIT: LEFT: RYAN MCCLYMONT, RIGHT: GORDON TRIBBLE, USGS.

Hurricane Lane was an impactful event for the Hawaiian Islands. In August 2018, over a four-day period, the island of Hawai'i received an average of 17 inches of rainfall, with a four-day single-station maximum of 57 inches, making Hurricane Lane the wettest tropical cyclone ever recorded in Hawai'i. A recently published study, led by University of Hawai'i at Mānoa researchers, details the compounding hazards--fire and rain--produced by the storm.

"In this study we document what we believe to be the first instance of a hurricane causing both heavy rainfall and contributing to multiple instances of fire simultaneously," said Alison Nugent, lead author of the study and assistant professor of Atmospheric Sciences in the UH Mānoa School of Ocean and Earth Science and Technology (SOEST).

A team of UH Mānoa and East-West Center scientists analyzed multiple aspects of the storm's meteorology and climatology, the environmental conditions leading up to the storm, and documented the associated societal impacts.

They found that land-use characteristics and preceding moisture conditions exacerbated fire hazard, and both fire and rain severity were influenced by the hurricane environment and local topographic features. Conditions at the edge of the storm resulted in dry windy weather conducive to fire, while closer to the storm center, the incredibly moist atmosphere lifted by Hawai'i's mountains brought intense, long-lasting rainfall. The simultaneous occurrence of rain-driven flooding and landslides, strong winds, and multiple fires complicated emergency response.

The vulnerability of a population in any given location to the impacts of tropical cyclone hazards is determined by a multitude of interacting factors. Biophysical aspects include distance inland from the coast, terrain slope, coastal ecosystem integrity, and land surface cover. Socioeconomic factors include infrastructure quality, the availability of early warning systems, and capacity for evacuation and emergency response.

The background image shows a visible satellite image of Hurricane Lane on August 22nd, 2018 when its eye was centered near the Hawaiian Islands. The white dashed line indicates the track of Lane, labeled with dates and times (UTC), and the color of the hurricane symbol indicates the strength of winds in the storm

"The surprising thing about Hurricane Lane was that, despite never making landfall, the storm caused considerable damage and disruptions across the state from two rather contradictory things: fire and rain," said Nugent. "Severe flooding on the windward island of Hawai'i Island built over several days, and multiple fires initiated on the lee sides of Maui and O?ahu within hours of each other. Hurricane Lane is one of only three documented cases of hurricanes influencing wildland fire risk in real-time."  

In Hawai'i, landfall by hurricanes is relatively rare due to persistent vertical wind shear over the islands, which weakens hurricanes by essentially tipping them over. However, when hurricanes do occur near Hawai'i, the geography of the islands can exacerbate the hazards. The nearly 750 miles of coastline makes much of the state susceptible to coastal flooding, and the mountainous topography can enhance high-intensity rainfall, as well as intensifying wind speeds. In addition, the steep mountainous terrain can enhance flash flooding and trigger landslide events.

The study highlights Hawai'i's vulnerability to natural hazards and reveals that these events can place significant constraints on emergency responders. This research also demonstrates UH Mānoa's technical expertise across multiple disciplines--climatology, meteorology, water resources, fire science--to assess and predict the impacts of natural hazards and other climate-related events.

In the future the team plans to develop the analytical approaches and Hawai'i-focused climate products needed to assess and prepare for future impacts, especially in the context of a changing climate where intensity and frequency of extreme events is likely to increase.

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mammals, including humans, indicate equal connectivity

Pioneering study led by Tel Aviv University researchers contradicts widespread conjectures

AMERICAN FRIENDS OF TEL AVIV UNIVERSITY

 

Researchers at Tel Aviv University, led by Prof. Yaniv Assaf of the School of Neurobiology, Biochemistry and Biophysics and the Sagol School of Neuroscience and Prof. Yossi Yovel of the School of Zoology, the Sagol School of Neuroscience, and the Steinhardt Museum of Natural History, conducted a first-of-its-kind study designed to investigate brain connectivity in 130 mammalian species. The intriguing results, contradicting widespread conjectures, revealed that brain connectivity levels are equal in all mammals, including humans.

"We discovered that brain connectivity -- namely the efficiency of information transfer through the neural network -- does not depend on either the size or structure of any specific brain," says Prof. Assaf. "In other words, the brains of all mammals, from tiny mice through humans to large bulls and dolphins, exhibit equal connectivity, and information travels with the same efficiency within them. We also found that the brain preserves this balance via a special compensation mechanism: when connectivity between the hemispheres is high, connectivity within each hemisphere is relatively low, and vice versa."

Participants included researchers from the Kimron Veterinary Institute in Beit Dagan, the School of Computer Science at TAU and the Technion's Faculty of Medicine. The paper was published in Nature Neuroscience on June 8.

"Brain connectivity is a central feature, critical to the functioning of the brain," Prof. Assaf explains. "Many scientists have assumed that connectivity in the human brain is significantly higher compared to other animals, as a possible explanation for the superior functioning of the 'human animal.'" On the other hand, according to Prof. Yovel, "We know that key features are conserved throughout the evolutionary process. Thus, for example, all mammals have four limbs. In this project we wished to explore the possibility that brain connectivity may be a key feature of this kind -- maintained in all mammals regardless of their size or brain structure. To this end we used advanced research tools."

The project began with advanced diffusion MRI scans of the brains of about 130 mammals, each representing a different species. (All of the brains were removed from dead animals, and no animals were euthanized for the purposes of this study.) The brains, obtained from the Kimron Veterinary Institute, represented a very wide range of mammals -- from tiny bats weighing 10 grams to dolphins whose weight can reach hundreds of kilograms. Since the brains of about 100 of these mammals had never been MRI-scanned before, the project generated a novel and globally unique database. The brains of 32 living humans were also scanned in the same way. The unique technology, which detects the white matter in the brain, enabled the researchers to reconstruct the neural network: the neurons and their axons (nerve fibers) through which information is transferred, and the synapses (junctions) where they meet.

The next challenge was comparing the scans of different types of animals, whose brains vary greatly in size and/or structure. For this purpose the researchers employed tools from Network Theory, a branch of mathematics that enabled them to create and apply a uniform gauge of brain conductivity: the number of synopses a message must cross to get from one location to another in the neural network.

"A mammal's brain consists of two hemispheres connected to each other by a set of neural fibers (axons) that transfer information," Prof. Assaf explains. "For every brain we scanned, we measured four connectivity gages: connectivity in each hemisphere (intrahemispheric connections), connectivity between the two hemispheres (interhemispheric), and overall connectivity. We discovered that overall brain connectivity remains the same for all mammals, large or small, including humans. In other words, information travels from one location to another through the same number of synapses. It must be said, however, that different brains use different strategies to preserve this equal measure of overall connectivity: some exhibit strong interhemispheric connectivity and weaker connectivity within the hemispheres, while others display the opposite."

Prof. Yovel describes another interesting discovery. "We found that variations in connectivity compensation characterize not only different species but also different individuals within the same species," he says. "In other words, the brains of some rats, bats, or humans exhibit higher interhemispheric connectivity at the expense of connectivity within the hemispheres, and the other way around -- compared to others of the same species. It would be fascinating to hypothesize how different types of brain connectivity may affect various cognitive functions or human capabilities such as sports, music or math. Such questions will be addressed in our future research."

"Our study revealed a universal law: Conservation of Brain Connectivity," Prof. Assaf concludes. "This law denotes that the efficiency of information transfer in the brain's neural network is equal in all mammals, including humans. We also discovered a compensation mechanism which balances the connectivity in every mammalian brain. This mechanism ensures that high connectivity in a specific area of the brain, possibly manifested through some special talent (e.g. sports or music) is always countered by relatively low connectivity in another part of the brain. In future projects we will investigate how the brain compensates for the enhanced connectivity associated with specific capabilities and learning processes."

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American Friends of Tel Aviv University supports Israel's most influential, comprehensive and sought-after center of higher learning, Tel Aviv University (TAU). TAU is recognized and celebrated internationally for creating an innovative, entrepreneurial culture on campus that generates inventions, startups and economic development in Israel. TAU is ranked ninth in the world, and first in Israel, for producing start-up founders of billion-dollar companies, an achievement that surpassed several Ivy League universities. To date, 2,500 US patents have been filed by Tel Aviv University researchers -- ranking TAU #1 in Israel, #10 outside of the US and #66 in the world.

Researchers boost koala spotting system

QUEENSLAND UNIVERSITY OF TECHNOLOGY

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VIDEO: ASSOCIATE PROFESSOR GRANT HAMILTON IS USING AI TO FIND KOALAS IN AREAS HIT BY BUSHFIRES. view more 

CREDIT: QUT

QUT researchers have published an improved and innovative method for estimating the number of koalas in an area detected by using drones and an artificial intelligent algorithm as they continue the quest of identifying surviving koala populations in bushfire areas.

In an article published in the journal Ecology and Evolution, the researchers led by Associate Professor Grant Hamilton detail the statistical method that uses the number of koalas automatically detected in infrared images of bushland as a starting point.

Their previous research, published in the Nature journal Scientific Reports, showed their system was more reliable and less invasive than traditional animal population monitoring techniques.

Professor Hamilton, who co-authored the latest study with PhD student Evangeline Corcoran and Dr Simon Denman, said all methods for spotting koalas in heavy bushland faced challenges, whether spotters used traditional methods such as people looking up at the trees, dogs brought in to sniff out the koalas or high-tech tools such as infrared drones.

"All abundance estimation methods are at least a bit wrong - that's why they're called estimates," Professor Hamilton said.

The lead author on the article, Evangeline Corcoran, said that finding wildlife in a complex environment could be very challenging.

"We never have perfect knowledge, so we never know exactly how many koalas were there when we do a count," Ms Corcoran said.

"No matter how accurate the drone cameras, a koala could be hiding behind a branch when the drone flies over the area or perhaps one koala is counted twice in an aerial survey.

"That's why we generally have a margin of error. We use different terminology, but for example in general terms our current count might have an error margin of plus or minus ten per cent. That means we're confident that the true number of koalas is somewhere within the margin of error

"By accounting for different factors about the site that can impact on how many koalas we detect, we're making the margin of error smaller and so making our estimates more accurate.

"In this way, we are deriving a count figure that accounts for more factors such as temperature, which is an important consideration because our thermal cameras give a more accurate estimate when its colder, and the density of the forest canopy."

Professor Hamilton is currently involved in a project in which he is using his artificial intelligence (AI) system that uses drones and infrared imaging in a collaborative project to count Kangaroo Island's surviving koala population after the recent devastating bushfires.

Professor Hamilton's system for detecting koalas in bushland begins with drones fitted infrared cameras covering an area in a "lawnmower" pattern at early morning and during the colder months so that the heat of the koalas better stands out.

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To contribute to Professor Hamilton's work in this area, go to https://alumni-and-friends.qut.edu.au/giving/save-the-koalas. All funds donated will go towards improved monitoring to assist with wildlife recovery.

Media contact:

Rod Chester, QUT Media, 07 3138 9449, rod.chester@qut.edu.au

After hours: Rose Trapnell, 0407 585 901, media@qut.edu.au

Stepping-down asthma medication may reduce costs without worsening health out

Study suggests that many clinicians may be prescribing higher levels of treatment than is clinically indicated

PLOS

 

International guidelines for asthma treatment recommend clinicians find the minimum effective dose that can control symptoms, yet asthma patients are increasingly prescribed high doses of medication. A study published in PLOS Medicine by Dr. Chloe Bloom at Imperial College London, United Kingdom and colleagues found that stepping-down medication doses did not increase asthma exacerbations and could significantly reduce medication costs.

Over 5.4 million people receive asthma treatment in the UK and asthma medication comprises 13% of total primary care prescribing costs. Additionally, prolonged use and higher doses of asthma medications are associated with a higher risk for systemic adverse effects and high medication costs. To understand the symptoms, diagnoses, and prescription patterns, the researchers conducted a population-based observational study, accessing primary care electronic health records of 508,459 asthma patients treated in the UK between 2001-2017. Using clinical asthma codes, researchers then evaluated a cohort of regular asthma preventer users, analyzing changes in prescribed asthma medications and subsequent health outcomes for 31,379 patients who were stepped down in their asthma medicine prescriptions. The cost impact of medication step-down was then calculated for the cohort using 2019 drug costs.

Inhaled corticosteroids (ICS) are the second most prescribed medication, suggesting the potential to reduce costs considerably with appropriate stepping-down among asthma patients. Additionally, stepping-down just half of all suitable patients on long-acting β agonist (LABA) medication could save around £17 million, equivalent to 2% of the UK's asthma budget. This research is only the second real-world study to compare stepped-down patients to controls and one of the major strengths is inclusion of a nationally representative study population and large sample size. However, the researchers were limited in their ability to track which prescribed medications were dispensed and adhered to, a question that may be important for future studies.

According to the authors, "Although stepping-down of treatment is recommended by clinical guidelines, we found that it happened infrequently. Stepping down ICS or add-on therapy did not appear to worsen health outcomes but did appear to result in significant cost savings."

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Research Article

In your coverage please use this URL to provide access to the freely available paper: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003145

Funding: The authors received no specific funding for this work.

Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests. CIB reports financial support outside the submitted work from Asthma UK, Chiesi, and AstraZeneca. AS reports that his institution received research support from Asthma UK for the Asthma UK Centre for Applied Research, outside the submitted work. AS is a member of the Editorial Board of PLOS Medicine. JKQ reports grants from MRC, GSK, BLF, Asthma UK, The Health Foundation, IQVIA, AstraZeneca, Chiesi, BI, Bayer; personal fees from AZ, Chiesi, BI, Bayer, and TEVA, outside the submitted work. LDP declares no competing interests associated with this manuscript.

Citation: Bloom CI, de Preux L, Sheikh A, Quint JK (2020) Health and cost impact of stepping down asthma medication for UK patients, 2001-2017: A population-based observational study. PLoS Med 17(7): e1003145. https://doi.org/10.1371/journal.pmed.1003145

Author Affiliations: Imperial College London, UK; University of Edinburgh, UK

Global warming boosts heat-related cardiovascular hospitalizations, study finds

PLOS

 

The impact of high temperatures on hospitalizations due to cardiovascular diseases has increased over the past two decades in Queensland, Australia, according to a new study published this week in PLOS Medicine by Shanshan Li and Yuming Guo of Monash University, Australia, and colleagues.

Extreme temperatures--both cold and hot--are known risk factors for cardiovascular morbidity and mortality. Global climate change is increasing the duration and intensity of such extreme temperatures. Previous studies have found a decrease in the association between hot temperatures and cardiovascular deaths, suggesting that people may have adapted to the warming climate. In the new study, researchers used data on 1,855,717 cardiovascular hospitalizations in Queensland, Australia between 1995 and 2016 to study the association between temperature and hospitalizations.

Between 1995 and 2016, the daily mean temperature in Queensland increased from 20.9°C to 21.7°C and the annual number of cardiovascular hospitalizations increased from 46,730 to 123,477. In all ages, sexes and climate zones, the relative risk of cardiovascular hospitalizations associated with high temperatures increased over time but the impact of cold temperatures decreased over time. The increasing magnitude of heat impacts was larger in men than in women (p=0.002) and larger in people aged less than 70 years compared to people aged 70 years and over (p<0 .001="" p="">

"Given the increased associations between hot temperatures and cardiovascular hospitalization and the acceleration of global warming, we highlight a worrying trend that the burden of cardiovascular healthcare facilities is to increase over time on high temperature days," the authors say.

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Research Article

In your coverage please use this URL to provide access to the freely available paper: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003104

Funding: The study was supported by Taishan Scholar Program. YG was supported by a Career Development Fellowship of the Australian National Health and Medical Research Council (#APP1107107 & #APP1163693). SL was supported by an Early Career Fellowship of Australian National Health and Medical Research Council (#APP1109193).

Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: YG is a member of the Editorial Board of PLOS Medicine.

Citation: Lu P, Xia G, Zhao Q, Xu R, Li S, Guo Y (2020) Temporal trends of the association between ambient temperature and hospitalisations for cardiovascular diseases in Queensland, Australia from 1995 to 2016: A time-stratified case-crossover study. PLoS Med 17(7): e1003176. https://doi.org/10.1371/journal.pmed.1003176

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

Cinnamon may improve blood sugar control in people with prediabetes

THE ENDOCRINE SOCIETY

 WASHINGTON--Cinnamon improves blood sugar control in people with prediabetes and could slow the progression to type 2 diabetes, according to a new study published in the Journal of the Endocrine Society.

It is estimated that nearly 90 million people in the United States have prediabetes, which occurs when blood sugar levels are higher than normal and often leads to type 2 diabetes. Identifying strategies to prevent the progression from prediabetes to type 2 diabetes is challenging, yet important for a large population.

"Our 12-week study showed beneficial effects of adding cinnamon to the diet on keeping blood sugar levels stable in participants with prediabetes," said the study's corresponding author, Giulio R. Romeo, M.D., of Joslin Diabetes Center in Boston, Mass. "These findings provide the rationale for longer and larger studies to address if cinnamon can reduce the risk of developing type 2 diabetes over time."

The randomized clinical trial investigated the effects of cinnamon supplementation in 51 participants with prediabetes. Participants were given a 500 mg cinnamon capsule or placebo three times a day for 12 weeks. The researchers found that cinnamon supplements lowered abnormal fasting glucose levels and improved the body's response to eating a meal with carbohydrates, which are hallmarks of prediabetes. Cinnamon was well tolerated and was not associated with specific side effects or adverse events.

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Other authors include Junhee Lee of the Kyung Hee University in Seoul, South Korea; Christopher M. Mulla of Joslin Diabetes Center and the Landstuhl Regional Medical Center in Landstuhl, Germany; Youngmin Noh of Joslin Diabetes Center and the Kyung Hee University; Casey Holden of Joslin Diabetes Center; and Byung-Cheol Lee of the Kyung Hee University.

The study was supported by the Ministry of Health and Welfare in South Korea.

The manuscript, "Influence of Cinnamon on Glycemic Control in Subjects with Prediabetes: A Randomized Controlled Trial," was published online.

Endocrinologists are at the core of solving the most pressing health problems of our time, from diabetes and obesity to infertility, bone health, and hormone-related cancers.

The Endocrine Society is the world's oldest and largest organization of scientists devoted to hormone research and physicians who care for people with hormone-related conditions.

The Society has more than 18,000 members, including scientists, physicians, educators, nurses and students in 122 countries. To learn more about the Society and the field of endocrinology, visit our site at?http://www.endocrine.org. Follow us on Twitter at @TheEndoSociety and @EndoMedia.

Asteroid shower on the Earth-Moon system 800 million years ago revealed by lunar craters

OSAKA UNIVERSITY

 

IMAGE: AN ASTEROID SHOWER ON THE EARTH-MOON SYSTEM view more 

CREDIT: ARTIST'S ILLUSTRATION, CREDIT: MURAYAMA/OSAKA UNIV.

A research team led by Osaka University investigated the formation ages of 59 lunar craters with a diameter of approximately 20 km using the Terrain Camera (TC) onboard the lunar orbiter spacecraft Kaguya.

Kaguya (formerly SELENE, for SELenological and ENgineering Explorer), is a Japanese Space Agency (JAXA) lunar orbiter mission.

This group demonstrated that an asteroid of 100 km in diameter was disrupted 800 million years ago (800 Ma) and that at least (4-5)×1016 kg of meteoroids, approximately 30-60 times more than the Chicxulub impact, must have plunged into the Earth-Moon system. Their research results were published in Nature Communications.

Since a thin layer of iridium (Ir) enrichment (a rare earth element) 65.5 Ma had been detected worldwide, it is thought that an asteroid of 10-15 km in diameter hit the Earth and caused or greatly contributed to the Cretaceous mass extinction.

The probability of an asteroid of this size striking Earth is thought to be once in 100 million years. It is known that impact craters on Earth created before 600 Ma have been erased over the years by erosion, volcanism, and other geologic processes. Thus, to find out about ancient meteoroid impacts on Earth, they investigated the Moon, which has almost no erosion.

They investigated the formation age distribution of 59 large craters with diameters larger than approximately 20 km by examining the density of 0.1-1 km-diameter craters in the ejecta of these 59 craters. One of these examples is the Copernicus crater (93 km in diameter) and its surrounding craters (Figure 2). The density of 860 craters with diameter of 0.1-1 km (shown in green) was examined to derive the age of the Copernicus crater. As a result, 8 of 59 craters were found to be formed simultaneously (17 by a spike model), a world first. (Figure 3)

Considering crater scaling laws and collision probabilities with the Earth and Moon, at least (4-5)×1016 kg of meteoroids, approximately 30-60 times more than the Chicxulub impact, must have struck the Earth immediately before the Cryogenian (720-635 Ma), which was an era of great environmental and biological changes.

In addition, given the disruption age and orbit elements of existing asteroid families, it is highly likely that the disruption of the parent body of C-type asteroid Eulalia caused an asteroid shower. A C-type asteroid is a class expected to contain carbon in analogy to the carbonaceous chondrites (meteorites).

Because Eulalia's surface reflectance is similar to that of near-Earth C-type asteroid Ryugu, Eulalia has drawn attention as a parent body of a C-type Rubble pile, a celestial body consisting of numerous pieces of rock near the Earth. (Sugita et al. 2019)

Ryugu was probed by the asteroid explorer Hayabusa2, an asteroid sample-return mission operated by JAXA.

From these considerations, they concluded that sporadic meteorite bombardment due to the disruption of asteroids 800 Ma caused the following:

-Some of the resulting fragments fell on terrestrial planets and the Sun,
-Others stayed in an asteroid belt as the Eulalia family, and
-Remnants had orbital evolution as a member of near-Earth asteroids.

This research suggests the following possibilities:

1. An asteroid shower may have brought a large amount of phosphorus (P) to the Earth, affecting the terrestrial surface environment,
2. A recent C-type asteroid shower may have contaminated the lunar surface with volatile elements,
3. The Eulalia family, the parent body of a near-Earth C-type asteroid, may have brought an asteroid shower to the Earth and the Moon.

Lead author Professor Terada says, "Our research results have provided a novel perspective on earth science and planetary science. They will yield a wide range of positive effects in various research fields."

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The article, "Asteroid shower on the Earth-Moon system immediately before the Cryogenian period revealed by KAGUYA" was published in Nature Communications at DOI: https://doi.org/10.1038/s41467-020-17115-6

About Osaka University

Osaka University was founded in 1931 as one of the seven imperial universities of Japan and is now one of Japan's leading comprehensive universities with a broad disciplinary spectrum. This strength is coupled with a singular drive for innovation that extends throughout the scientific process, from fundamental research to the creation of applied technology with positive economic impacts. Its commitment to innovation has been recognized in Japan and around the world, being named Japan's most innovative university in 2015 (Reuters 2015 Top 100) and one of the most innovative institutions in the world in 2017 (Innovative Universities and the Nature Index Innovation 2017). Now, Osaka University is leveraging its role as a Designated National University Corporation selected by the Ministry of Education, Culture, Sports, Science and Technology to contribute to innovation for human welfare, sustainable development of society, and social transformation.

Website: https://resou.osaka-u.ac.jp/en/top

Combining handwashing, mask-wearing and social distancing best in preventing COVID-19

PLOS

 

Both self-imposed prevention measures such as hand-washing, mask-wearing and social distancing, as well as government-imposed social distancing can help mitigate and delay a COVID-19 epidemic, according to a new study published this week in PLOS Medicine by Alexandra Teslya of University Medical Center Utrecht, Utrecht, The Netherlands and colleagues.

The coronavirus disease COVID-19 has spread to nearly every country in the world and public health policymakers are seeking recommendations on how to delay or flatten its peak. In the new study, researchers developed a computational model of the spread of COVID-19 based on known information about the epidemiology of the disease. They used the model to study the predicted effect of various prevention measures on the number and timing of coronavirus cases.

If a population quickly becomes aware of the coronavirus and effective prevention measures, self-imposed prevention measures can both diminish and postpone the peak number of cases, the model showed. If the efficacy of the self-imposed measures exceeds 50%, a large epidemic can be prevented. If self-imposed prevention measures are slow to catch on, however, they may only reduce the number of cases but not delay a peak. Early implementation of government-imposed social distancing, however, was found to delay but not reduce the peak of the COVID-19 epidemic. Combining self-imposed prevention measures--particularly if adopted quickly and by a large portion of the population--with government-imposed social distancing has the potential to both delay and shrink the peak of the epidemic. The model did not account for demographics or heterogeneity in contact patterns of different people.

"We stress the importance of disease awareness in controlling the ongoing epidemic and recommend that, in addition to policies on social distancing, government and public health institutions mobilize people to adopt self-imposed measures with proven efficacy in order to successfully tackle COVID-19," the authors say.

In an accompanying Perspective, Professor Yuming Guo of Monash University, Australia, and colleagues write that the new findings are important not only in minimizing initial outbreaks of COVID-19, but in strategies to prevent second epidemics. Improving awareness of self-imposed interventions is critical to prevent wide-spreading epidemics, particularly among ethnic minorities and elderly populations who are at risk. "Many of the self-imposed prevention strategies have very limited impact on the economy but contribute very significantly to epidemic control and are likely to play a very substantial role in control," they write.

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Research Article

In your coverage please use this URL to provide access to the freely available paper: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003104

Funding: This study was funded by the following: Fundação para a Ciência e a Tecnologia, project reference 131_596787873, awarded to GR, https://www.fct.pt; ZonMw 91216062, awarded to MEK, funded MEK and AT, https://www.zonmw.nl/en/; One Health European Joint Programme Horizon 2020 project 773830 (award recipient is not an author of this manuscript) funded NGG and MCJB, https://ec.europa.eu/programmes/horizon2020/en; and Aidsfonds Netherlands project P-29704 (award recipient is not an author of this manuscript) funded GR, https://aidsfonds.nl/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: MEK is a member of the Editorial Board of PLOS Medicine. The other authors have declared that no competing interests exist.

Citation: Teslya A, Pham TM, Godijk NG, Kretzschmar ME, Bootsma MCJ, Rozhnova G (2020) Impact of self-imposed prevention measures and short-term government-imposed social distancing on mitigating and delaying a COVID-19 epidemic: A modelling study. PLoS Med 17(7): e1003166. https://doi.org/10.1371/journal.pmed.1003166

Author Affiliations: University Medical Center Utrecht, Utrecht, the Netherlands

Perspective

In your coverage please use this URL to provide access to the freely available paper: http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003240

Funding: The work is supported by the Bill & Melinda Gates Foundation. LZ is supported by the National Natural Science Foundation of China (Grant number: 8191101420); Outstanding Young Scholars Funding (Grant number: 3111500001); Xi'an Jiaotong University Basic Research and Profession Grant (Grant number: xtr022019003) and Xi'an Jiaotong University Young Talent Support Grant (Grant number: YX6J004). YG is supported by Career Development Fellowships of the Australian National Health and Medical Research Council (Grant number: APP1163693).

Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: YG is a member of the Editorial Board of PLOS Medicine.

Citation: Zhang L, Tao Y, Shen M, Fairley CK, Guo Y (2020) Can self-imposed prevention measures mitigate the COVID-19 epidemic? PLoS Med 17(7): e1003240. https://doi.org/10.1371/journal.pmed.1003240

Author Affiliations: Monash University; Zhengzhou University, Zhengzhou, Henan, China; China-Australia Joint Research Center for Infectious Diseases, School of Public Health, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, PR China

WHITE FOLKS WITH GUNS ON DRUGS

Rural firearm-suicides impacted by socioeconomic, environmental factors

Targeting areas with high opioid and firearm use may be a better strategy for prevention

BOSTON UNIVERSITY SCHOOL OF MEDICINE

(Boston)--In an attempt to address the escalating rate of self-inflicted firearm injury deaths in rural America, researchers are proposing interventions to reduce these suicides be community-based and include programs to reduce other diseases of despair, such as heart and liver diseases, diabetes and accidental opioid overdose. The recent decline in life expectancy of Americans has been attributed to these diseases of despair and appear to primarily afflict white rural America.

Given the gaps in understanding the socioeconomic and environmental factors related to firearm suicide deaths, researchers from Boston University School of Medicine (BUSM) sought to understand the patterns and clustering of rural counties in the U.S. based on firearm suicide and drug-related death rates in the context of economic and socioeconomic characteristics.

The researchers examined rural county-specific data from 2012 to 2016 of firearm suicide deaths, homicide rate, drug related mortality rate, opioid prescription rate, median home price, veteran population, violent crime rate, primary economic dependence of counties, county socioeconomic characteristics such as low employment, persistent poverty, population loss and whether the county is a retirement destination.

"Our findings suggest that the affected rural populations are very diverse and there are collective environmental risk factors, including the primary economies that play an important role in firearm suicide rates. Hence, focusing on actions related to firearms alone without considering the built environment may not reduce these deaths," explained corresponding author Bindu Kalesan, PhD, MPH, assistant professor of medicine at BUSM.

The study has important policy and prevention implications, researchers say. "While most programs focus on risk factors, including the temporary removal of firearms from home, safe storage and denying sale of firearms, we need to incorporate other factors such as primary economies, using a broader public health approach to target interventions in high-risk areas which can simultaneously reduce gun suicides and opioid deaths," added Kalesan, who also is an assistant professor of community health services at Boston University School of Public Health.

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These findings appear online in the Journal of Surgical Research.

Racial discrimination may adversely impact cognition in African Americans

BOSTON UNIVERSITY SCHOOL OF MEDICINE

(Boston)--Experiences of racism are associated with lower subjective cognitive function (SCF) among African-American women.

Rates of incident dementia and Alzheimer's Disease (AD) are higher in African Americans than in white Americans. In many studies, older African Americans perform more poorly on neuropsychological cognition tests compared to white Americans. Experiences of racism are common among African Americans, with 50 percent or more respondents to a 2017 national survey reporting such experiences. These institutional and daily forms of racism have been associated with increased risks of various conditions that can impair cognition, including depression, poor sleep, type 2 diabetes and hypertension.

Using data from the Black Women's Health Study (a prospective cohort study established in 1995, when 59,000 black women aged 21 through 69 years enrolled by completing health questionnaires) researchers from Boston University's Slone Epidemiology Center quantified the association between experiences of racism and SCF, based on six questions about memory and cognition.

They found that experiences of both daily and institutional racism were associated with decreased SCF. Women reporting the highest level of daily racism had 2.75 times the risk of poor SCF as women reporting the lowest level of daily racism. Women in the highest category of institutional racism had 2.66 times the risk of poor SCF as those who reported no such experiences.

"Our findings of a positive association of experiences of racism with poorer subjective cognitive function are consistent with previous work demonstrating that higher perceived psychological stress is associated with greater subjective memory decline," explains senior author Lynn Rosenberg, ScD, epidemiologist at the Slone Epidemiology Center at Boston University and a principal investigator of the Black Women's Health Study. "Our work suggests that the chronic stress associated with racial discrimination may contribute to racial disparities in cognition and AD," added Rosenberg, who is also a professor of epidemiology at Boston University School of Public Health.

Future work is needed to examine whether exposure to institutional and daily racism accelerates conversion to Alzheimer's dementia and/or increases levels of AD biomarkers, such as cerebrospinal fluid or PET markers of amyloid ? and tau pathology, according to the researchers.

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These findings appear online in the journal Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring.

This study was supported in part by the National Cancer Institute grants R01CA058420 and UM1CA164974, the National Institute on Aging grant R21AG060269 and Alzheimer's Association grant AARG-17-529566.