Thursday, March 18, 2021

Tired at the office? Take a quick break; your work will benefit

WE USED TO CALL THEM SMOKE BREAKS

NORTH CAROLINA STATE UNIVERSITY

Research News

Recent research shows that people are more likely to take "microbreaks" at work on days when they're tired - but that's not a bad thing. The researchers found microbreaks seem to help tired employees bounce back from their morning fatigue and engage with their work better over the course of the day.

At issue are microbreaks, which are short, voluntary and impromptu respites in the workday. Microbreaks include discretionary activities such as having a snack, chatting with a colleague, stretching or working on a crossword puzzle.

"A microbreak is, by definition, short," says Sophia Cho, co-author of a paper on the work and an assistant professor of psychology at North Carolina State University. "But a five-minute break can be golden if you take it at the right time. Our study shows that it is in a company's best interest to give employees autonomy in terms of taking microbreaks when they are needed - it helps employees effectively manage their energy and engage in their work throughout the day."

The new paper is based on two studies that explored issues related to microbreaks in the workday. Specifically, the studies were aimed at improving our understanding of how people boost or maintain their energy levels throughout the day in order to engage with work even when they start the day already exhausted. The studies also examined which factors might play a role in determining whether people took microbreaks, or what they did during those microbreaks.

The first study surveyed 98 workers in the United States. Study participants were asked to fill out two surveys per day for 10 consecutive workdays. The surveys were completed in the morning and at the end of workday. The second study included 222 workers in South Korea. This study had participants complete three surveys per day for five workdays. Study participants completed the surveys in the morning, after lunch and at the end of the workday.

Survey questions in both studies were aimed at collecting data about each study participant's sleep quality, levels of fatigue, as well as their engagement with their work and their experiences at the workplace that day. In the studies, the researchers analyzed the survey data with statistical tools to examine day-to-day fluctuations in sleep quality, fatigue, work behavior and engagement in varying types of microbreaks.

The results were straightforward: on days that people were already fatigued when they arrived at work, they tended to take microbreaks more frequently. And taking microbreaks helped them maintain their energy level. This, in turn, helped them meet work demands and engage with work better.

"Basically, microbreaks help you manage your energy resources over the course of the day - and that's particularly beneficial on days when you're tired," Cho says.

In addition, the researchers found that people were more likely to take microbreaks if they felt their employer cared about the health and well-being of its workers.

"When people think their employer cares about their health, they feel more empowered to freely make decisions about when to take microbreaks and what type of microbreaks to take," Cho says. "And that is ultimately good for both the employer and the employee."

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The paper, "Daily microbreaks in a self-regulatory resources lens: Perceived health climate as a contextual moderator via microbreak autonomy," is published in the Journal of Applied Psychology. The paper was co-authored by Sooyeol Kim of the National University of Singapore, and by Youngah Park of the University of Illinois, Urbana-Champaign.

 

Standing out from the crowd

Research team from Göttingen and Groningen Universities shows importance of investors on uniqueness of company strategies

UNIVERSITY OF GÖTTINGEN

Research News

Corporate strategies should be as unique as possible, in fact highly specific to each individual company. This enables companies to compete successfully in the long term. However, the capital market and others, including analysts, often react negatively to the idea of unique strategies. The reason is that deviating from typical industry standards makes them more complex to evaluate. This regularly discourages companies from focusing on unique strategies, even though they would be beneficial for the company in the long term. This contradiction is known as the "uniqueness paradox". A research team from the Universities of Göttingen and Groningen has investigated the influence of different types of investors on the extent of the paradox and thus on the choice of unique strategies. The results were published in Strategic Management Journal.

The researchers analyzed data from around 900 listed US companies over a period of twelve years. The focus was on US companies because of the larger number of companies listed on the stock exchange. The main findings: a company's investors have significant influence on the uniqueness of its chosen strategy; and "dedicated" investors (e.g. pension funds) exert increasing influence. Their actions are characterized by the fact that they take a long-term perspective and are prepared to take a close look at the company's strategies. They can help resolve the uniqueness paradox, as they can recognize the value of unique strategies for long-term corporate development. "They are more likely to encourage management to implement these strategies," says co-author Professor Michael Wolff, who holds the Chair of Management and Controlling at the University of Göttingen. "This is especially true for industries where companies are more difficult for the capital market to assess because, for example, corporate profits vary widely."

The research team derives specific recommendations for action from the study. Firstly, the study shows companies the great importance of continuous and, above all, detailed strategy communication with investors. In particular, it is important to explain the reasons in a transparent and coherent manner for following a different course from the strategies of other companies in the same industry. Secondly, the study shows investors how important their function as owners is in actively engaging with corporate strategy in order to encourage management to operate in the long term. Thirdly, the study makes it clear that investors who have so far acted very passively should be made more accountable by institutions that regulate the capital market to engage more intensively with companies and their strategies.

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Original publication: Jana Oehmichen, Sebastian Firk, Michael Wolff, Franz Maybüchen (2021). Standing out from the crowd: Dedicated institutional investors and strategy uniqueness, Strategic Management Journal. https://doi.org/10.1002/smj.3269

 

Easing the burden on transgender and nonbinary graduate students

Report offers suggestions to relax a "toxic" atmosphere

UNIVERSITY OF HOUSTON

Research News

IMAGE

IMAGE: NATHAN G. SMITH, UNIVERSITY OF HOUSTON ASSOCIATE PROFESSOR IN THE COUNSELING PSYCHOLOGY DOCTORAL PROGRAM AT THE UNIVERSITY OF HOUSTON COLLEGE OF EDUCATION AND CHAIR OF THE DEPARTMENT OF PSYCHOLOGICAL, HEALTH,... view more 

CREDIT: UNIVERSITY OF HOUSTON

It would surprise no one that pursuing a graduate degree can be a stressful endeavor, and for students who are transgender and nonbinary (TNB), the atmosphere can become toxic, according to University of Houston researcher Nathan Grant Smith. In a new paper published in Higher Education, Smith provides an analysis of current literature pertaining to TNB graduate student experiences and suggests interventions in graduate education to create more supportive environments for TNB students.

"Nearly 50% of graduate students report experiencing emotional or psychological distress during their enrollment in graduate school. Levels of distress are particularly high for transgender and nonbinary graduate students who experience daily discrimination and marginalization," reports Smith, associate professor in the counseling psychology doctoral program at the UH College of Education and chair of the Department of Psychological, Health, and Learning Sciences.

In compiling and analyzing the literature, Smith was joined by Douglas Knutson of Oklahoma State University. Their team included Em Matsuno, Palo Alto University; Chloe Goldbach, Southern Illinois University Carbondale; and Halleh Hashtpari, The University of Utah.

The existing literature suggests that discrimination against TNB college students is increasing and that discrimination on college campuses (e.g., reduced access to housing, restricted access to bathrooms and locker rooms) is associated with negative psychological outcomes such as suicidal ideation. Smith and team offer a social-ecological model of transgender stigma and stigma interventions.

"We are providing a framework for understanding that people interact with the outside world at different levels," said Smith. "Those levels are one-on-one, interpersonal with groups and structural with interactions between policies and norms of an institution."

Since all levels are connected, Smith suggests everyone start by doing their own exploration of gender and challenge their internal biases that will surely impact others. For example, consider how your gender identity helped or hindered your current career path and other life experiences. Reflect on which gender pronouns you use (e.g., he/him/ his, she/her/hers, they/them/theirs) and how you would feel if others repeatedly used incorrect pronouns when talking to or about you.

"Students who are trained in TNB-affirmative environments will enter the workforce, equipped to cultivate more empowering and diverse spaces for their colleagues, their families, and for the communities in which they live," said Smith. "We encourage everyone to think of TNB inclusion as an opportunity and as an affective experience based in empathy, love, and an impulse toward community building."

Some of the team's recommendations include:

  • Creating affirming spaces for TNB graduate students
  • Reviewing - and making inclusive - university paperwork, such as applications, intake forms for student services (like counseling and health), program handbooks, course syllabi, website pages, faculty pages and student evaluations
  • Inclusion of gender-affirming care in student insurance plans
  • Training of counseling center and health center staff

    "These and other steps are crucial for building a foundation of empathy and humility in order to provide safe, inclusive and affirming spaces for TNB graduate students," Smith reported.

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  • There Have Been At Least 3,795 Hate Incidents Against Asian Americans During The Pandemic, A New Report Shows

    "Time and time again, we’re seen as outsiders to be excluded, incarcerated, deported," said Russell Jeung, cofounder of Stop AAPI Hate.


    Julia Reinstein BuzzFeed News Reporter
    Posted on March 16, 2021

    Ringo Chiu / Getty Images
    A protester holds a sign at a Los Angeles rally on Feb. 20 to raise awareness of anti-Asian violence after 84-year-old Thai immigrant Vicha Ratanapakdee was killed in a random assault.


    Throughout the past year, Asian Americans have had to survive more than just a deadly pandemic: They've also faced a rise in verbal and physical attacks as a result of racist scapegoating over COVID-19.

    A new report by the organization Stop AAPI Hate shows there have been at least 3,795 reported hate incidents targeting Asian Americans in just the past year alone, from March 19, 2020, to Feb. 28.

    Though the report does not include numbers from previous years for comparison, other data has shown an extreme uptick in these attacks. Though overall hate crimes decreased by 7% in 16 major US cities in 2020, anti-Asian hate crimes increased 149%, first spiking in March and April when COVID-19 began its spread, according to California State University's Center for the Study of Hate and Extremism.

    Of the incidents documented by Stop AAPI Hate, 68% involved verbal harassment, and 11% involved physical assault. Shunning, defined as the "deliberate avoidance of Asian Americans," made up 20% of reports. Civil rights violations, such as discrimination in the workplace or being refused service by a business, made up 8.5% of reports, with another 6.8% being for online harassment.

    Women reported attacks at more than twice the rate of men, and Chinese Americans numbered over 42% of the victims.


    Ringo Chiu / Getty Images

    Because the report analyzed solely self-reported attacks, the actual numbers are likely even higher.

    "The number of hate incidents reported to our center represent only a fraction of the number of hate incidents that actually occur, but it does show how vulnerable Asian Americans are to discrimination, and the types of discrimination they face," the report says.

    Racism against Asian Americans has exploded in the past year, at both the individual level and in the country's highest offices. Throughout the pandemic, Donald Trump repeatedly pushed blame for COVID-19 onto China, calling it the "China Virus" and "Kung Flu." He continued to do so, and denied it was racist, even after a reporter questioned him on the increase in attacks on Chinese Americans.

    The new report was published just weeks after a San Francisco man was arrested on assault charges for allegedly pushing three Asian Americans to the ground, including one who was 91. One of the others he attacked, a 55-year-old woman, was knocked out.

    These assaults were just three of many that have been recently reported across the US. In January, 84-year-old Thai immigrant Vicha Ratanapakdee died of a brain hemorrhage after a random attacker slammed him to the ground in San Francisco. Throughout the pandemic, Asian Americans have been chemically burnedmocked and robbed on video, and kicked in the face. In at least two other instances, including one of a family of three, the attackers have allegedly tried to kill the victims.

    The racism Asian Americans are facing now is keenly reminiscent of the "yellow peril" stereotype that first swept the US in the 1850s, Russell Jeung, cofounder of Stop AAPI Hate and a professor of Asian American Studies at San Francisco State University, told BuzzFeed News.


    "It’s the fear that Asians would come and overcome the West with their hordes [of] racialized, diseased bodies, and take over — dominate," Jeung said. "In the 19th century, that fear was stoked with the diseases of smallpox, cholera, and leprosy, and [there was] the fear of Chinese taking away white workers’ jobs, so they passed the Chinese Exclusion Act."

    A century and a half ago, this stereotype was just as dangerous to Asian Americans as it is now, he added. "My great-grandparents' home in Monterey, they had a village of 200 people, and they were burned down and burned out and had to move to San Francisco’s Chinatown to avoid the racism."

    It's part of a pattern across US history, he said.

    "We had Japanese American incarceration during World War II, [and] we had Islamophobia after 9/11," Jeung said. "Time and time again, we’re seen as outsiders to be excluded, incarcerated, deported."



    CBS News@CBSNews

    Biden calls out the rise in hate crimes against Asian Americans during the pandemic, saying they're "attacked, harassed, blamed and scapegoated" "They are forced to live in fear for their lives just walking down streets in America. It's wrong, it's un-American and it must stop"01:12 AM - 12 Mar 2021
    Reply Retweet FavoriteTwitter: @CBSNews


    In a speech on March 11, President Joe Biden condemned "vicious hate crimes against Asian Americans who've been harassed, attacked, blamed, and scapegoated."

    "They are forced to live in fear for their lives just walking down streets in America," he said. "It's wrong, it's un-American, and it must stop."


    Jeung said he was glad to see Biden speaking out on the attacks, and he hopes to see the president's words translated into concrete actions, such as expanding ethnic studies education and civil rights protections.

    The Stop AAPI Hate report includes details of some of the victims' stories, which include being harassed in public, coughed or spat on, called slurs, and several incidents in which people were told to "go back" to China.

    "A white man catcalled me, then aggressively followed me down the block, and got
    inches from my face and yelled 'Ch*nk!' and 'C*nt!' after realizing I was Asian," one person from Brooklyn reported. "Lots of neighbors were standing outside their homes and no one intervened."


    "My boyfriend and I were riding the metro into DC," another person, from Annandale, Virginia, said. "When on the escalator in the transfer station, a man repeatedly punched my back and pushed past us. At the top, he circled back toward us, followed us, repeatedly shouted 'Chinese b**ch' at me, fake coughed
    at, and physically threatened us."


    In some cases, the victims reported being conspicuously shunned or avoided.

    "I came into the coffee shop at Mercato and people started leaving the area where I sat one by one," one person, from Naples, Florida, said. "People started coming in and they sat on the other side of the coffee shop away from me. I became isolated on one side of the coffee shop."
    A Car Drove Into A Homeless Encampment In California, Killing Three People

    "We train for this, but there’s just no way to prepare for something that’s this devastating."

    Amber Jamieson BuzzFeed News Reporter
    Posted on March 15, 2021

    Gregory Bull / AP
    A car involved in a deadly crash sits at the scene on March 15, 2021, in San Diego.


    Three people were killed Monday after a car veered into an encampment of unsheltered people in San Diego, authorities said.

    The incident took place around 9 a.m. in a tunnel beneath a bridge in downtown, where many people live in tents and other temporary shelters on sidewalks. Nine people in all were struck, with two of the survivors left critically injured.

    Police arrested the driver, 71-year-old Craig Voss, on suspicion of three counts of vehicular manslaughter and a felony DUI.


    Gregory Bull / AP
    Lisa Brotzman, right, stands with Terry Goffigan at the scene of the deadly accident on March 15 in San Diego.

    “Our crews found, obviously, a tragic incident under the bridge," San Diego Fire Chief Colin Stowell said at a news conference.

    The three people who were killed died at the scene, he added.

    "We train for this, but there’s just no way to prepare for something that’s this devastating," the fire chief said. “This was a very tragic, tragic accident that will make an impact on a lot of lives.”


    NBC San Diego / Via nbcsandiego.com

    One witness, Ronnie Williams, described the horrifying event to NBC San Diego.

    “I turned around and I saw yellow headlights and next thing you know, I was almost getting sucked under the car. And then I managed to pull my leg out from under the car right here," said Williams, who is also unsheltered. “You could see everything popping up, going in the air, dragging — it was, it was very loud. It was like something you see in a movie scene."

    Officials noted that the incident highlighted the need for more permanent housing options to get people off the street.

    “The street is not a home and this tragedy further highlights the dangers of living on the streets,” Hanan Scrapper, the San Diego regional director of PATH, an organization working to end homelessness, said in a statement.

    City Council President Stephen Whitburn said the deadly crash was "stark evidence of the need to find permanent solutions to the homelessness crisis so that no San Diegans are forced to seek shelter in unsafe places such as under bridges and in tunnels that vehicles pass through."

    Global campaign calls on apparel brands to pay their workers, reform broken industry



    Today, MSN joins with more than 200 trade union and civil society organizations in over 40 countries in launching the #PayYourWorkers #RespectLabourRights campaign.

    Other Canadian endorsers of the campaign include Above Ground, Canadian Network on Corporate Accountability (CNCA), Centre International de Solidarité Ouvrière (CISO), Canadian Union of Public Employees (CUPE), Ontario Secondary School Teachers Federation (OSSTF), Oxfam Canada, Public Service Alliance of Canada (PSAC), SHARE, Steelworkers Humanity Fund and USW, and Workers United Canada Council.

    As the health and economic impacts of the coronavirus pandemic continue to be felt by vulnerable workers in Canada, the pandemic is pushing millions of already low-paid garment workers around the world deeper into poverty and hunger. A year into the crisis, many apparel brands have returned to profitability and some have even raked in record level earnings, while workers in their supply chains struggle to survive.

    PayYourWorkers #RespectLabourRights is calling on apparel retailers and brands to contribute funds to sustain the incomes of the workers who make their products throughout the pandemic, ensure respect for their right to organise and bargain collectively, and sign onto a severance guarantee fund so that workers are never left penniless if their factories go bankrupt in the future. In this week of action, the brand targets are Amazon, Nike and Next, a UK fast fashion retailer. As the campaign progresses, other brands will also be targeted.

    The campaign launch follows the release last week of a major report from the Business & Human Rights Resource Centre (BHRRC), which found that 16 brands, including Mark’s (Canadian Tire), linked to unpaid wages and benefits in supplier factories in various countries, had made a combined $10 billion in profits in the second half of 2020.

    PayYourWorkers.org, the campaign website, was launched today and is available in eight languages. We invite you to join the campaign, sign the petition and add your organization’s name to the list of endorsers. Read MSN’s media release on the campaign here.

    Read the BHRRC Report: Wage theft and pandemic profits: The right to a living wage for garment workers, available here.

    We’ll keep you updated as the campaign progresses.

    Lynda Yanz


    The Maquila Solidarity Network (MSN) is a labour and women's rights organization that supports the efforts of workers in global supply chains to win improved wages and working conditions. Please consider supporting MSN's important work by making an online contribution or by sending a cheque to the address below.

    606 Shaw St.
    Toronto, ON M6G 3L6
    Canada

    Study uncovers safety concerns with some air purifiers

    Joint university research finds some air purifiers may actually increase harmful airborne chemicals

    COLORADO STATE UNIVERSITY

    Research News

    The market for air purifiers is booming, but a new study has found that some air cleaning technologies marketed for COVID-19 may be ineffective and have unintended health consequences.

    The study, authored by researchers at Illinois Tech, Portland State University, and Colorado State University, found that cleaning up one harmful air pollutant can create a suite of others.

    Both chamber and field tests found that an ionizing device led to a decrease in some volatile organic compounds (VOCs) including xylenes, but an increase in others, most prominently oxygenated VOCs (e.g., acetone, ethanol) and toluene, substances commonly found in paints, paint strippers, aerosol sprays and pesticides. According to the EPA, exposure to VOCs has been linked to a range of health effects from eye, nose and throat irritation, headaches, loss of coordination and nausea, to damage to liver, kidney and central nervous system, and some organics can cause cancer in animals, some are suspected or known to cause cancer in humans.

    The study, published this week in Building and Environment, mimicked real-world operating conditions for these ionization devices to test the effectiveness and potential to form chemical byproducts in environments similar to where we all live, work, and learn.

    One of the most popular types of air purifiers on the market right now are ion-generating systems, including 'bipolar ionization' devices that electrically charge particles so they settle out of the air faster, and are generally marketed to kill bacteria, fungi, and viruses.

    Understandably, the "virus-killing" capability has drawn attention and been heavily featured in advertising over the past year and led to a flood of new and revamped products on the market.

    However, the study finds that the air purifier marketplace is fraught with inadequate test standards, confusing terminology, and a lack of peer-reviewed studies of their effectiveness and safety. Unlike air filtration (where air is pushed through a filter to remove airborne pollutants), there has been very little research on the effectiveness and side effects of "additive" air cleaning methods like ionizing devices.

    "Manufacturers and third-party test labs commonly demonstrate their product's effectiveness using chamber tests, but these test reports often don't use experimental conditions that could show how the device actually performs in real-world conditions," said Brent Stephens, Chair of the Department of Civil, Architectural, and Environmental Engineering at Illinois Tech. "To the extent that there are testing standards for ionization and other devices, those are largely industry-led standards that remain underdeveloped at this point, focused mostly on ensuring just one pollutant, ozone, is not generated during operation."

    In everyday operating conditions, ions added to occupied environments such as a school or office building can react with other compounds present in indoor air, which can potentially lead to the formation of harmful byproducts such as formaldehyde and ozone. Ions can also rapidly bind to other gases and spur the formation of new 'ultrafine' particles, which are known air pollutants. But little independent data exists on these mechanisms.

    The research team conducted a series of experiments on the operation of a commercially available in-duct bipolar ionization device. Lab tests were conducted with air sampling of particulate matter and gases in a large semi-furnished chamber and in a field test with an ionizer device installed in an air handling unit serving an occupied office building. The research also found that despite small changes in particle concentrations, there was very little net effect on the overall concentration of PM2.5 in the air.

    According to the EPA, particulate matter contains microscopic solids or liquid droplets that are so small that they can be inhaled and cause serious health problems. Particles less than 2.5 micrometers in diameter, also known as fine particles or PM2.5, pose the greatest risk to health as they can get deep into your lungs and some may even get into your bloodstream. Numerous scientific studies have linked fine particle pollution exposure to a range of health impacts, including premature death in people with heart or lung disease, nonfatal heart attacks, irregular heartbeat, aggravated asthma, decreased lung function, irritation of the airways, coughing or difficulty breathing.

    Health impacts of air ionizers are largely unknown, although a small number of recent studies give cause for concern. In August 2020, a study concluded that exposure to negative ions was associated with increased systemic oxidative stress levels (a marker of cardiovascular health), and despite reduced indoor particulate matter concentrations, there were no beneficial changes to respiratory health.

    Another recent study of air ionizers in school classrooms reduced particulate matter concentrations led to some improvements in respiratory health among 11-14 year old children, the ionizers had an adverse effect on heart rate variability (a measure of cardiovascular health), meaning that any benefit to the lungs came at a cost to the heart.

    "We should have a much better understanding of these effects before widespread use of these types of devices," said Delphine Farmer, Associate Professor in the Department of Chemistry at Colorado State University and a co-lead author of the paper.

    "Without peer-reviewed research into the health impacts of these devices, we risk substituting one harmful agent for another," said Stephens. "We urge others to follow guidance from organizations like the U.S. EPA and ASHRAE, which generally recommend the use of established, evidence-based measures to clean indoor air, including high efficiency particle filtration and enhanced ventilation, in addition to face coverings and physical distancing, to help reduce airborne transmission of COVID-19."

    ###

    The authors of this research are Yicheng Zeng, Prashik Manwatkar, Marina Beke, Insung Kang, Akram Ali, Mohammad Heidarinejad, and Brent Stephens from Illinois Tech, Aurélie Laguerre and Elliott Gall from Portland State University, and Delphine Farmer from Colorado State University.

    Meandering rivers create "counter-point bars" no matter underlying geology

    UNIVERSITY OF TEXAS AT AUSTIN

    Research News

    It's not uncommon for crescent-shaped swaths of sand to dot the shorelines of meandering rivers. These swaths usually appear along the inner side of a river bend, where the bank wraps around the sandy patch, forming deposits known as a "point bars."

    When they appear along an outer bank, which curves the opposite way, they form "counter-point" bars, which are usually interpreted by geoscientists as an anomaly: a sign that something - such as a patch of erosion-resistant rocks - is interfering with the river's usual manner of sediment deposition.

    But according to research led by The University of Texas at Austin, counter-point bars are not the oddities they're often made out to be. In fact, they're a perfectly normal part of the meandering process.

    "You don't need a resistant substrate, you can get beautiful [counter-point] bars without it," said Zoltán Sylvester, a research scientist at UT's Bureau of Economic Geology who led the study.

    The finding suggests that counter-point bars - and the unique geology and ecology associated with them - are more common than previously thought. Building awareness around that fact can help geoscientists be on the lookout for counter-point bars in geological formations deposited by rivers in the past, and understand how they may be influencing the flow of hydrocarbons and water passing though them.

    CAPTION

    Satellite images of the Mamoré River colored to illustrate changes in flow path and sediment deposition as point bars (red) and counter-point bars (blue). From 2005-2010, the river (dark blue) undergoes a neck cutoff (light blue). This change in flow path causes small and highly curved bends to form (bends 1 and 2). Counter point bars form behind the bend 2 as it migrates downstream.

    CREDIT

    Sylvester et al.

    The research was published in the Geological Society of America Bulletin on March 12.

    The co-authors are David Mohrig, a professor at the UT Jackson School of Geosciences; Paul Durkin, a professor at the University of Manitoba; and Stephen Hubbard, a professor at the University of Calgary.

    Rivers are constantly on the move. For meandering rivers, this means carving out new paths and reactivating old ones as they snake across a landscape over time.

    The researchers observed this behavior in both an idealized computer model and in nature, using satellite photos of a stretch of Bolivia's Mamoré River, which is known for quickly changing its path. The satellite photos captured how the river changed over 32 years, from 1986 - 2018.

    In both the model and the Mamoré, counter-point bars appeared. The researchers found that the appearance was linked directly to short, high curvature bends: little spikes in a river's path.

    The researchers observed that these spikes frequently form when the river's course is abruptly changed, such as when a new oxbow lake forms through cutoff, or after reconnecting with an old oxbow lake.

    But the sharp bends don't stay put, they start migrating in the downstream direction. And as they rapidly move downstream, they create the conditions for sediment to accumulate around the bend as a counter-point bar.

    The study shows a number of instances of this happening in the Mamoré. For example, in 2010, a sharp bend (bend 2 in the image) forms when an ox-bow lake reconnects with a downstream portion of the river. By 2018, the bend has moved about 1.5 miles downstream, with counter-point deposits along the shoreline marking its path.

    Geomorphologists and engineers knew for some time that long-term change along a river can be described in terms of local and upstream values of curvature (places where the river seems to wrap around a small circle have high curvatures). In the study, the researchers used a formula that uses these curvature values to determine the likelihood of a counter-point bar forming at a particular location.

    Sylvester said that he was surprised at how well this formula - and the simplified models used in part to derive it - worked to explain what was thought to be a complex phenomenon.

    "Natural rivers, they are actually not that far from what these really simple models predict," Sylvester said.

    This is not the first time that Sylvester's research has revealed that river behavior can be governed by relatively simple rules. In 2019, he led a study published in Geology that described a direct relationship between bend sharpness and river migration.

    Superficially, point bars and counter-point bars look quite similar and frequently blend into one another. But counter-point bars are distinct environments: compared to point bars, they have finer sediments and lower topography, making them more prone to flooding and hosting lakes. These characteristics create unique ecological niches along rivers. But they are also geologically important, with ancient counter-point bar deposits preserved underground influencing the flow of fluids, such as water and oil and gas.

    Mathieu Lapôtre, a geoscientist and assistant professor at Stanford University, said that recognizing that counter-point bars can readily form in meandering rivers - and having a formula for predicting where they will form - is a significant advancement.

    "Altogether, the results of Sylvester et al. have important implications for a range of scientific and engineering questions," he said.

    ###

    The research was funded by the bureau's Quantitative Clastics Laboratory research consortium


    CAPTION

    A computer-created graphic of a river meandering and associated sediment deposits. The lighter blue represents the river's current flow. The darker blue represents old areas of flow that have been cut off due to the river's meandering. The striped regions along the flow paths represent sediment deposits in the form of point bars (red) and counter-point bars (blue).

    CREDIT

    Credit: Sylvester et al.