Friday, February 14, 2020

French unions played key role in protecting workers' mental health

During a three-year organizational restructuring at France Telecom that began in 2007—which called for the downsizing of 22,000 employees, often based on ethically questionable methods—there was a wave of employee suicides. Published reports put the total number of deaths at 35.

Virginia Doellgast, associate professor of comparative employment relations in Cornell University's ILR School, examines the role unions played in the aftermath of those deaths. Her paper, "After the Social Crisis: The Transformation of Employment Relations at France Telecom," was published Feb. 11 in Socio-Economic Review.

The researchers highlight France Telecom labor unions' approaches to studying and publicizing the negative effects of employment restructuring on workers' psychosocial health. The unions were able to influence how the suicides were interpreted—both within the firm and in the media—then communicate their findings to workers, managers and the public.

In 2009, when the press reported high rates of suicides at the company, the unions were ready with a well-organized message, backed by their survey findings: The company and its management were to blame. As a result, unions gained a formal role in monitoring management practices to make sure they did not threaten workers' psychosocial health.

That led to December's landmark decision by a Paris court, which found the company and several former top executives guilty of "collective moral harassment."

According to Doellgast, the France Telecom case holds lessons for U.S. unions struggling with similar problems of growing job insecurity and intensifying performance pressure. She has recently worked with the Communications Workers of America on a survey measuring worker stress and burnout, sleep problems, use of medication, repetitive strain injuries, and fears of outsourcing and downsizing.

"One lesson for U.S. unions is that change starts by getting workers to understand that stress-related problems are widespread and to mobilize around the demand for good, healthy jobs," Doellgast said. "Also, real power comes from communicating these issues to the public and to policymakers. Companies are more likely to prioritize worker health when they fear losing customers, and when they fear fines and jail time for their top executives."

Doellgast said the unions' ability to bring the case to the courts and the resulting landmark decision could have far-reaching consequences.

"Does the company just have a responsibility to its shareholders, or does it have a responsibility to its other stakeholders, which include its workers?" she said. "This case shows the critical role of unions in making the case for this 'stakeholder' view of the firm: Companies are part of society, and managers should make sure they're not killing their employees to make short-term profits."French telecom company Orange convicted over suicides

More information: Socio-Economic Review, academic.oup.com/ser/advance-a … /ser/mwaa006/5733937

Having fewer children reduced the education gap in China

by Jeff Grabmeier, The Ohio State University

JUST LIKE IN KERALA INDIA WHERE WOMEN BECAME BETTER EDUCATED THEY ALSO USED CONTRACEPTION MORE AND REDUCED THEIR FAMILY SIZE

Credit: CC0 Public Domain

A new study uses China's one-child policy to show that having fewer children leads women to achieve higher levels of education.

The research found that the one-child policy alone accounted for about half of the additional education that women in China achieved after the policy was put in place.

"The findings suggest that some Chinese women anticipated having fewer children due to the one-child policy and they postponed marriage and postponed having children while they increased their education," said Xuan Jiang, a postdoctoral researcher in economics at The Ohio State University.

Jiang's study was published recently in the journal Contemporary Economic Policy.

Population data collected by the Chinese government since 2010 made it possible for Jiang to analyze how fertility decisions affect education in women. There has been no other way to study the issue in this way before, she said.

As such, she emphasized that the study is not defending the one-child policy, which critics say led to human rights abuses. Moreover, the results may have broader implications beyond China for explaining the link between motherhood and education.

"Economists have wanted to know why the education gap between men and women has closed in many countries. This study shows that reductions in fertility may play an important role," she said.

Jiang used data from the ongoing Chinese Family Panel Studies, a nationally representative annual longitudinal survey conducted by Peking University and funded by the Chinese government.

China's one-child policy was instituted in 1979 to control the country's rapidly growing population. But it didn't apply equally to all groups. This study focused on the Han, the ethnic majority in China who were most strictly controlled by the law.

Jiang compared two groups: an older generation (born 1950-1959) whose education decisions would not have been affected by the one-child policy and a younger generation (born 1960-1980) whose decisions would be impacted.

Overall, while men born in 1950 had significantly more education than women born that year, men and women born in 1980 had about equal levels—nearly nine years of schooling.

Jiang first compared Han women versus Han men from older and younger generations.

The results showed that, after taking into account other factors that could have affected educational attainment, the one-child policy was responsible for increasing Han women's years of schooling by 1.28 years compared to Han men. That explains 53 percent of the 2.38-year increase in education attainment of women born between 1950 and 1980.

"Being able to explain more than half of educational attainment with one factor—the one-child policy—is enormous," Jiang said. "That is very surprising for economists."

She noted that in a broader context, women in countries worldwide experienced increases in education in the same time frame. Could there be other worldwide social forces at work that affected women in China?

To control for that possibility, Jiang conducted a second analysis that compared Han women to non-Han women in China who were not subject to the strict one-child policy.

The results were nearly identical to the first analysis: The Han women's educational attainment increased by 1.29 years compared to non-Han women.

Jiang did another test, looking specifically at young women who had one or more parents who were members of the ruling Communist party.

"The Communist Party implemented the one-child policy and there were punishments for party members whose families did not follow the birth quota," Jiang said.

"So you would expect that the one-child policy would have an even stronger effect for young women whose parents were members."

And that is indeed what she found: The one-child policy had a more robust impact on increasing education among children of Communist Party members.

Jiang also analyzed what happened to women after their schooling was over.

Results showed that the one-child policy delayed women's first marriages, delayed how soon they had a child and increased how many entered the job market.

"Women anticipated having fewer children, which may have delayed their entry into parenthood and even delayed the decision to get married, which allowed them to get more education," Jiang said.

"And with the further education, they were more likely to get jobs."

The results show the powerful influence that the one-child policy had on Chinese society, she said.

"The one-child policy fundamentally changed the lives and family structure of the generations born in the 1960s and later."

The effects of China's one-child policy on women's education

More information: Xuan Jiang. FAMILY PLANNING AND WOMEN'S EDUCATIONAL ATTAINMENT: EVIDENCE FROM THE ONE‐CHILD POLICY, Contemporary Economic Policy (2020). DOI: 10.1111/coep.12462

What is the best way to encourage innovation? Competitive pay may be the answer

by Christine Clark, University of California - San Diego

RESEARCH BIAS REVEALED

Economists and business leaders agree that innovation is a major force behind economic growth, but many disagree on what is the best way to encourage workers to produce the "think-outside-of-the-box" ideas that create newer and better products and services. New research from the University of California San Diego indicates that competitive "winner-takes-all" pay structures are most effective in getting the creative juices flowing that help fuel economic growth.

The findings are based on a study authored by professor of economics Joshua Graff Zivin and assistant professor of management Elizabeth Lyons who partnered with Thermo Fisher Scientific, one of the globe's largest bio tech companies, in creating a contest for the Baja California office. Participants in the competition, which was open to all non-management employees of Thermo Fisher and other tech companies in the region, were asked to design digital solutions to help share medical equipment across small healthcare clinics in the region.

The competition was created to test which of two common compensation models produced more novel ideas. Those who signed up were randomly selected to compete in either the "winner-takes-all" category, in which there was one prize of $15,000 awarded to first place, or the "top 10" category, in which the same amount of prize money was spread out among the top 10 entries.

"Participants under the winner-takes-all compensation scheme submitted proposals that were significantly more novel than their counterparts in the other scheme," said the authors of National Bureau of Economic Research (NBER) working paper, who both hold appointments with the UC San Diego School of Global Policy and Strategy. "While the two groups did not statistically differ from one another on their overall scores, the risk taking encouraged by the competition with a single prize resulted in innovators pursuing more creative solutions."

They added, "These findings are significant because the 21st century economy is one that prizes novelty. Firms view it as an important source of comparative advantage. It is also an essential ingredient in the development of technological breakthroughs that transform markets with major impacts to consumers and producers."

How firms can produce more creative ideas with a limited amount of resources

Most modern-day mechanisms created by chief technology officer (CTOs) and management gurus designed to spark innovation often rely on performance-based-pay and hinge on assumptions regarding the ability and ambitions of employees and their risk preferences. However, the results from the NBER paper show that with identical groups of innovators, companies can increase the innovative output of employees just by changing how they pay them.

"Those competing for one big prize had to push further in making their results creative; however what is most surprising is that this is a relatively low-cost way for companies to induce more radical innovation," Lyons noted.

Though there was more risk vs. reward in the "winner-takes-all" category, both produced the about the same number of submissions (20 in "top 10" category and 22 in the "winner-takes-all" category), indicating that having less of a chance of winning a monitory award did not have an impact on the amount of work output.

The entries were judged by a panel of six experts. Half of the judges were from industry (Thermo Fisher and Teradata) and the other half were from academia (computer sciences professors from local universities in the Baja California region).

The novelty of the submissions was evaluated on a scale from one to five, relative to what is currently and/or soon to be available on the market. The lowest possible score of one was given for proposed solutions already on the market and the highest score of five was awarded to submissions in which no one else has thought of a similar idea.

Those who entered could work as an individual or in teams. The results of teams vs. individual entries in both categories are consistent with other studies, showing that teams with diversified skill-sets and deepened professional experience produced better entries than that of individuals. However, the team entries in the "winner-takes-all" category were again more novel than the group work in the "top 10" category.

Subsequently, participants in both categories were surveyed on their risk preferences. Not surprisingly, those less averse to risk performed better in the "winner-takes-all" category.

The results also revealed that women who submitted entries in the contest performed better than average in both categories of the competition.

In conclusion, the authors noted that genius is not created by incentives, but empowered by them.

"It is important to recognize that incentives alone are insufficient to spark creativity," they wrote. "More work is required to understand the raw ingredients that shape the relationship between creativity and compensation."

Students given incentives to innovate are just as skilled as the self-motivated, research finds

More information: Joshua Graff Zivin et al, The Effects of Prize Structures on Innovative Performance, (2020). DOI: 10.3386/w26737

For bacteria, your community determines whether you evolve or not

by Hayley Dunning, Imperial College London

A study of puddles has shown that bacteria evolve and adapt differently depending on the make-up of the community of bacteria they live within.

The findings could have implications for better understanding how bacteria evolve resistance to antibiotics, or for modelling how beneficial communities of bacteria are likely to respond to environmental changes and global heating.

For example, the researchers say that to tackle bacteria that are resistant to antibiotics, scientists need to understand not just the bug causing infections, but the whole community that these bacteria live with in a person's body.

Bacteria often live in large communities of hundreds or thousands of different species. These all interact, sometimes negatively, by competing for resources, and sometimes positively, for example when the waste from one species can be used by another.

The bacteria in the communities often need to evolve to adapt to changes, and if they are unable to adapt this can have knock-on effects for humans. For example, as lakes warm up because of global heating, the bacteria within them need to adapt and evolve.

These communities of bacteria improve water quality by breaking down organic matter, but if they can't adapt, they will not be able to perform the valuable service of cleaning the water.

Fundamental repercussions for evolution

Because bacterial communities contain so many species, it has been difficult for scientists to uncover what drives individual species to evolve, and what determines whether they ultimately succeed or fail to adapt.

Now, in research published in Nature Communications, a team led by Imperial College London scientists have performed a unique set of experiments that have unraveled some of the mystery.

They found that the same species of bacteria evolves and adapts differently depending on the make-up of the community of bacteria they live within.

Lead researcher Dr. Thomas Scheuerl, from the Department of Life Sciences at Imperial and the University of Innsbruck, said: "Bacterial communities are incredibly complex and diverse, and our study shows that how a bacterial species interacts with its community has fundamental repercussions for its evolutionary path.

"Scientists have debated how much of an effect community has on evolution, but our result shows clearly that when we want to understand how species adapt to new environments, the local community cannot be ignored."

Drivers of evolution

Previously, scientists have tried to track the evolution of bacterial species by isolating them from their communities, or by assembling artificial communities of a few well-studied species. This was because it was considered too difficult to study real natural communities as they contain so many species.

The latest study, however, used natural communities from the puddles that collect at the bases of beech trees. These communities are relatively simple, containing on average 25-200 species.

Within each community, the team identified and partially isolated several focus species to track their evolution. They isolated the bacteria in bags used for dialysis, which separated them physically from the community in the water, but allowed them to exchange chemicals that are used as resources or to signal between cells.

They tracked 22 focal species in eight different bacterial communities, allowing them to determine which factors affected their evolution. They found that the diversity of the community—how many different species it contained and how abundant they were—was a primary driver affecting evolution.

A more diverse community meant an individual species would be less likely to evolve and adapt. The team reasoned this was because in a diverse community there were likely to be other species that could already exploit the niche better, such as using a certain resource. In a less diverse community, there would be more opportunity to take on new roles that were not already taken by other species.

The team also found that genome size (the amount of DNA a species has) and initial fitness (how fast the bacteria grow and divide under harsh conditions) were important factors influencing a species' evolution.

Truer to life

Dr. Scheuerl said: "Isolating species from their natural habitats makes them easier to study, but will remove some of the natural controls on evolution, making the results less true to life.

"The strength of our study was that we allowed multiple factors—both intrinsic to the bacteria and how it interacts with the community—to act in parallel in a situation that is very close what would be found in nature."

Dr. Damian Rivett, previously at Imperial and now at Manchester Metropolitan University, added: "Our study could have implications for example when studying antibiotic resistance. If a strain is isolated and its evolution tracked, this may be very different to how it evolves in the community inside a person's body."

The team now want to study more closely what factors in the community affect the evolution of individual species, and how all the species interact with each other.

Double the stress slows down evolution

More information: Thomas Scheuerl et al. Bacterial adaptation is constrained in complex communities, Nature Communications (2020). DOI: 10.1038/s41467-020-14570-z

Preparing for climate change

by American Chemical Society

As global temperatures continue to rise, scientists are warning the world to brace for heat waves, extreme storms, wildfires and other dire consequences. While chemists are actively searching for new ways to mitigate climate change, they are also developing technologies to allow people and ecosystems to not only survive, but thrive, in a warmer world, according to a special issue of Chemical & Engineering News (C&EN), the weekly newsmagazine of the American Chemical Society.

The challenges of adapting to climate change are many. Feeding the world's growing population is expected to become more difficult, as farmers battle prolonged droughts and heat waves, alternating with crop-damaging storms. Fragile ecosystems, like coral reefs, will be vulnerable to changing conditions such as warmer, acidified oceans. And cities around the world must update their infrastructure to prepare for extreme weather in the form of heat, fires and floods.

In a series of articles, C&EN describes how chemists will play a critical role in helping the world thrive in the face of climate change. In the area of agriculture, scientists are reengineering crops to increase yield and resist disease in varied soil and atmospheric conditions. Other researchers are working to preserve existing coral reefs while modifying corals' DNA to make the tiny creatures more resilient. Still other efforts focus on developing innovative solutions to help cities protect their infrastructure from heat and violent storms and safeguard their water security.

Earth's most biodiverse ecosystems face a perfect storm

More information: cen.acs.org/environment/climat … chemistry-help/98/i6

New technique reduces pathogen identification time from two weeks to less than one hour

by American Phytopathological Society

Karolina Pusz-Bochenska holding symptomatic AY-infected canola plant standing in a canola field. Credit: Karolina Pusz-Bochenska, Edel Perez-Lopez, Tim J. Dumonceaux, Chrystel Olivier, and Tyler J. Wist

New technique reduces pathogen identification time from two weeks to less than one hour

Transmitted by insects, especially the aster leafhopper, aster yellows (AY) outbreaks can cause severe production losses in many crops, including carrots, lettuce, and canola. Canola is a billion-dollar crop for Canada but the growing season in Western Canada is very short. Depending on the environmental conditions and number of infected leafhoppers, AY can be transmitted to canola in less than 24 hours and the leafhoppers can continue spreading the disease for the rest of their lives.

Scientists based in Saskatoon, Canada, developed a rapid, simple laboratory and field-adaptable DNA extraction method that allowed them to identify both plant pathogen and insect vector using molecular barcoding and gene sequencing. This method reduced the time from collection of insects to a positive identification of the presence of a pathogen from up to two weeks to less than one hour. They published their findings in Plant Health Progress.

"Using this methodology, we were able to go from DNA extraction to pathogen detection in less than one hour," according to lead author Karolina Pusz-Bochenska. "This rapid technique allows for same-day management decisions essential to preventing the spread of insect-transmitted pathogens."

To achieve this quick turnaround, Pusz-Bochenska and colleagues used DNA lysis paper to extract pathogen DNA, which was a novel choice that they combined with the rapid-detection potential of the sensitive and field-adaptable loop-mediated isothermal amplification (LAMP) assay. According to Pusz-Bochenska, this combination was groundbreaking.

"When the aster leafhoppers migrate into Canada in spring, they bring AY phytoplasmas that can cause devastating damage to canola crops, and we need a rapid-test to determine if these migrant leafhoppers are a threat or not. A rapid analysis of the leafhoppers allows us to estimate the infectivity of the population and forecast the risk to the crops, allowing the growers to make management decisions if the leafhoppers have arrived in their fields."

While this research focuses on agriculture, this techniques has potential applications to horticulture as well as animal and human health. For more details, read "A Rapid, Simple, Laboratory and Field-Adaptable DNA Extraction and Diagnostic Method Suitable for Insect-Transmitted Plant Pathogen and Insect Identification," which is freely available through the end of March.

Finally, a mug shot for a crop-killing NH pest

More information: Karolina Pusz-Bochenska et al, A Rapid, Simple, Laboratory and Field-Adaptable DNA Extraction and Diagnostic Method Suitable for Insect-Transmitted Plant Pathogen and Insect Identification, Plant Health Progress (2020). DOI: 10.1094/PHP-09-19-0063-FI

EPA fails to follow landmark law to protect children from pesticides in food

by Environmental Working Group

ENVIRONMENTAL POLLUTION AGENCY

The landmark Food Quality Protection Act requires the Environmental Protection Agency to protect children's health by applying an extra margin of safety to legal limits for pesticides in food. But an investigation by EWG, published this week in a peer-reviewed scientific journal, found that the EPA has failed to add the mandated children's health safety factor to the allowable limits for almost 90 percent of the most common pesticides.

The study in Environmental Health examined the EPA's risk assessments for 47 non-organophosphate pesticides since 2011, including those most commonly found on fresh fruits and vegetables, and found that the required additional tenfold safety factor was applied in only five cases.

"Given the potential health hazards of pesticides in our food, it is disturbing that the EPA has largely ignored the law's requirement to ensure adequate protection for children," said the study's author, Olga Naidenko, Ph.D., vice president for science investigations at EWG. "The added safety factor is essential to protect children from pesticides that can cause harm to the nervous system, hormonal disruption and cancer."

The Food Quality Protection Act of 1996, or FQPA, requires the EPA to set allowable levels for pesticides in a way that would "ensure that there is a reasonable certainty that no harm will result to infants and children from aggregate exposure to the pesticide chemical residue." It was hailed as a revolutionary recognition of the fact that children are more vulnerable to the effects of chemical pesticides than adults.

"Based on the strong consensus of the pediatric and the public health communities, the FQPA stated unequivocally that regulation of toxic pesticides must focus, first and foremost, on protecting infants and children," said Dr. Philip Landrigan, a pediatrician and epidemiologist who is director of the Program in Global Public Health and the Common Good at Boston College. "When the EPA fails to apply this principle, children may be exposed to levels of chemical pesticides that can profoundly harm their health."

Landrigan chaired the committee that authored "Pesticides in the Diets of Infants and Children," a 1993 report from the National Academy of Sciences. The groundbreaking study led to the FQPA's passage with bipartisan support and the backing of both industry and environmentalists.

"The FQPA was a revolution in how we think about pesticides' effects on children, but it does no good if the EPA doesn't use it," said EWG President Ken Cook. "It's not only necessary to protect kids' health, it's the law, and the EPA's failure to follow the law is an egregious betrayal of its responsibility."

Naidenko's study also examined EPA risk assessments for a particularly toxic class of pesticides called organophosphates, which act in the same way as nerve gases like sarin and are known to harm children's brains and nervous systems. She found that under the Obama administration, the tenfold children's health safety factor was proposed for all organophosphate insecticides.

By contrast, in four assessments of pyrethroid insecticides, the EPA under the Trump administration has proposed adding the FQPA safety factor to none. In human epidemiological studies conducted in the U.S. and in Denmark, exposure to pyrethroid insecticides was associated with increased risk of attention deficit hyperactivity disorder.

In 2017, the EPA reversed the Obama administration's FQPA determination for chlorpyrifos, the most widely used organophosphate pesticide in the U.S. Despite the Trump EPA's decision, in the wake of bans by Hawaii, California and New York, the main U.S. chlorpyrifos manufacturer recently announced it will stop making this chemical. It remains to be seen whether the Trump EPA will uphold the tenfold FQPA determination for the entire group of organophosphates.

The study also found that the Trump EPA has proposed to increase by 2.6-fold the allowable exposure to the herbicide metolachlor. The use of metolachlor has been on the rise for the past decade, with more than 60 million pounds sprayed annually, according to the U.S. Geological Survey.

Biomonitoring studies conducted by the Centers for Disease Control and Prevention and by independent researchers reported the presence of multiple pesticides and their byproducts in the American population, including herbicides such as glyphosate and 2,4-D, the bee-killing neonicotinoid insecticides, organophosphate and pyrethroid insecticides, and fungicide metabolites.

Experts call for overhaul of pesticide regulations

More information: Olga V. Naidenko, Application of the Food Quality Protection Act children's health safety factor in the U.S. EPA pesticide risk assessments, Environmental Health (2020). DOI: 10.1186/s12940-020-0571-6

Why C. difficile infection spreads despite increased sanitation practices

by Maria Iacobo, Massachusetts Institute of Technology

A microscopic image shows a culture of C. difficile cells and spores. MIT research suggests the risk of becoming colonized increases immediately following gastrointestinal disturbances that result in diarrhea. Credit: Dave VanInsberghe

New research from MIT suggests the risk of becoming colonized by Clostridium difficile (C. difficile) increases immediately following gastrointestinal (GI) disturbances that result in diarrhea.

Once widely considered an antibiotic- and hospital-associated pathogen, recent research into C. difficile has shown the infection is more frequently acquired outside of hospitals. Now, a team of researchers has shown that GI disturbances, such as those caused by food poisoning and laxative abuse, trigger susceptibility to colonization by C. difficile, and carriers remain C. difficile-positive for a year or longer.

"Our work helps show why the hospital and antibiotic association of C. difficile infections is an oversimplification of the risks and transmission patterns, and helps reconcile a lot of the observations that have followed the more recent revelation that transmission within hospitals is uncommon," says David VanInsberghe Ph.D. '19, a recent graduate of the MIT Department of Biology and lead author of the study. "Diarrheal events can trigger long-term Clostridium difficile colonization with recurrent blooms" in Nature Microbiology.

The researchers analyzed human gut microbiome time series studies conducted on individuals who had diarrhea illnesses and were not treated with antibiotics. Observing the colonization of C. difficile soon after the illnesses were acquired, they tested this association directly by feeding mice increasing quantities of laxatives while exposing them to non-pathogenic C. difficile spores. Their results suggest that GI disturbances create a window of susceptibility to C. difficile colonization during recovery.

Further, the researchers found that carriers shed C. difficile in highly variable amounts day-to-day; the number of C. difficile cells shed in a carrier's stool can increase by over 1,000 times in one day. These recurrent blooms likely influence the transmissibility of C. difficile outside of hospitals, and their unpredictability questions the reliability of single time-point diagnostics for detecting carriers.

"In our study, two of the people we followed with high temporal resolution became carriers outside of the hospital," says VanInsberghe, who is now a postdoc in the Department of Pathology at Emory University. "The observations we made from their data helped us understand how people become susceptible to colonization and what the short- and long-term patterns in C. difficile abundance in carriers look like. Those patterns told us a lot about how C. difficile can spread between people outside of hospitals."

"I believe that there is a lot of rethinking of C. diff infections at the moment and I hope our study will help contribute to ultimately better manage the risks associated with it," says Martin Polz, senior author of the study and a visiting professor in MIT's Parsons Laboratory for Environmental Science and Engineering within the MIT Department of Civil and Environmental Engineering.

Asymptomatic C. difficile ups risk for other hospital patients

More information: David VanInsberghe et al. Diarrhoeal events can trigger long-term Clostridium difficile colonization with recurrent blooms, Nature Microbiology (2020). DOI: 10.1038/s41564-020-0668-2

Pollinating opossums confirm decades-long theory

by Ecological Society of America

A violet-capped Woodnymph hummingbird visits the inflorescence. Credit: Felipe Amorim.

In Brazil there is a plant so strange that researchers predicted—and 27 years later, proved—that opossums are key to its pollination. The findings are published in the Ecological Society of America's journal Ecology.

The plant Scybalium fungiforme, a little-known fungus-like species of the family Balanophoraceae, has bunches of tiny pale flowers that are surrounded and housed by a hard surface of bracts—like on an artichoke. Because of their scale-like shape, the bracts must be opened or peeled back to expose the flowers and nectar to pollinators such as bees.

While most species in the Balanophoraceae plant family are primarily pollinated by bees and wasps, researchers at São Paulo State University in Botucatu, Brazil hypothesized something different. They thought that opossums, with their opposable thumbs, would be a key pollinator for S. fungiforme due to the challenging bracts covering the flowers.

In the early 1990s Patrícia Morellato, a professor at the university, first made the prediction. She and her colleagues studied the plant and they captured an opossum with nectar on its nose. There observations went unpublished because they did not record or obtain direct evidence of the opossums pollinating the flowers.

Felipe Amorim, assistant professor at the university and lead author on this study, did not encounter the plant until 2017, but hypothesized that a non-flying mammal is needed for pollination based on the flower morphology. In April 2019 his students independently hypothesized that perhaps rodents could act as the main pollinators of this species. "At that time, neither of us knew anything about the unpublished observations made by Patrícia in the '90s,'" he explains.

In this screenshot from the camera trap, a opossum visits the inflorescence (flowers) of the plant and peels back bracts to get to the nectar. Credit: Felipe Am

Amorim sent his colleague Morellato the footage. "When she watched the videos," he says, "she sent me a voice message as excited as we were when we first saw the opossum visiting the flowers, because it was the first time she saw something she predicted two and a half-decades ago!"

The researchers had made the opossum prediction based on "pollination syndrome"—the concept that floral attributes such as color, morphology, scent, and size reflect the adaptation of a plant species to pollination by a certain group of animals. Opossums, having "hands" with opposable thumbs, are capable of peeling back the scale-like leafs covering the flowers of S. fungiforme. The plant does have other floral visitors that act as secondary pollinators once the bracts are removed—bees and wasps dominate the crowd, but a surprising additional visitor was several hummingbirds.

"Based on the flower morphology," Amorim says, "Morellato, my students, and I could safely predict that this plant should be pollinated by non-flying mammals, but the occurrence of hummingbirds coming to the ground to visit these flowers was something completely unexpected to me." Morellato had not seen any hummingbirds visiting this species at her study site during the '90s, but researchers have more recently obtained indirect evidence that hummingbirds visit the plant in both study locations.

The authors hope to continue studying the pollinators of S. fungiforme to assess the efficiency of each group of flower visitor (mammals, hummingbirds, and bees and wasps) in order to quantify their contribution to the fruit production of this plant. They also want to analyze the chemical compounds of nectar and floral scent, which can reveal much about the adaptation of a plant for a given group of pollinator.

Overall, the story is an interesting one to tell, the culmination of nearly three decades of prediction and observation based on the hard shell surrounding a bunch of tiny flowers. Amorim contemplates that "at the time that non-flying mammals were first predicted as the pollinators of this fungus-like plant, I was about 11 years old, and most of the authors of this study haven't even had born!"

How flowers adapt to their pollinators

More information: Felipe W. Amorim et al, Good heavens what animal can pollinate it? A fungus‐like holoparasitic plant potentially pollinated by opossums, Ecology (2020). DOI: 10.1002/ecy.3001

Journal information: Ecology

Modified clay can remove herbicide from water

by University of Groningen

By creating neatly spaced slits in a clay mineral, University of Groningen Professor of Experimental Solid State Physics Petra Rudolf was able to filter water to remove a toxic herbicide. After removing the pollutant by heating the material, the clay can be reused. Together with colleagues from Greece, Rudolf presents this proof of principle study in the journal Environmental Science Nano.

In the Netherlands, a lot of sugar beets are grown. On these fields, the herbicide chloridazon is widely used. This compound is toxic to humans, does not break down in nature and will eventually seep into the groundwater. Chloridazon concentrations in groundwater are currently below the safety threshold but as it is persistent in the environment, they are expected to increase. "Water purification plants can break down chloridazon using UV light—but the breakdown products of chloridazon are also toxic," explains Rudolf.

Pillars

Rudolf has acquired a technique to make well-defined nanocavities in clay, which she adapted to trap the herbicide. "Clay is a layered mineral," Rudolf explains. "The layers have a negative charge and are separated by positive ions. We can replace those with molecular pillars of our own design." The natural clays are first washed and then treated with sodium salts. The sodium replaces the natural positive ions between the layers. "These sodium ions are surrounded by a water mantle, which pushes the layers slightly further apart. By simply adding the pillar molecules to the water, they will replace the sodium."

These pillars are usually made of silicon oxide, with an added chemical group that defines the affinity of the cavities. Rudolf: "In this case, we added copper ions to attract the chloridazon and its breakdown products." The functionalized clay absorbed the herbicide in significant amounts: nearly 900 milligrams per kilogram of clay. "This is a good result and we see scope to further increase the absorption." Furthermore, Rudolf and her colleagues have shown that the herbicide is removed by heating the clay, which can then be used again.

Groundwater

The first results were obtained using 10 times the highest concentration of chloridazon measured in the environment. Furthermore, the experiments were performed in clean water. "So, we need to repeat this in real groundwater, to see if other compounds affect the absorption." If all these tests yield positive results, the next question is how to make this clay into a product that can be used in water treatment. "The options are to add the clay to water and then retrieve it by filtration, or to build the clay into a membrane," explains Rudolf.

By altering the width of the slits and changing the affinity of the pillars, different chemical compounds could be caught by the functionalized clay. "We are testing systems to remove two other compounds from water," says Rudolf. "Furthermore, a similar system could be created using other layered materials, such as graphene oxide."

Team discloses the formation of burning ice in oceanic clay rich sediment

More information: Feng Yan et al, Smectite clay pillared with copper complexed polyhedral oligosilsesquioxane for adsorption of chloridazon and its metabolites, Environmental Science: Nano (2019). DOI: 10.1039/C9EN00974D

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