Culture

Announcing a new publication for BIO Integration journal. In this opinion article the authors Tianhong Yao, Huirong Lin, Jingsong Mao, Shuaidong Huo and Gang Liu from Xiamen University, Xiamen, China discuss CT imaging features of patients infected with 2019 novel coronavirus.

Novel coronavirus pneumonia is an acute, infectious pneumonia caused by a novel coronavirus infection. Computed tomographic (CT) imaging is one of the main methods to screen and diagnose patients with this disease. In this article the authors discuss the importance and clinical value of chest CT examination in the diagnosis of COVID-19, and the pulmonary CT findings of COVID-19 patients in different stages are briefly summarized, providing a reference document for the CT diagnosis of COVID-19 patients.

Damage to the brain gray matter plays an important role in the progression of multiple sclerosis. This study now shows that such damage can be caused by inflammatory reactions that lead to loss of synapses, which impairs neural activity.

Multiple sclerosis (MS) is a chronic inflammatory disease that affects the central nervous system, in which nerve cells are attacked by the patient's own immune system. In many cases, the disease develops into a progressive form, which is characterized by a shift of pathology from the white matter to the gray matter, for instance to the cerebral cortex. This phase of the disease has so far been difficult to treat and its underlying causes are poorly understood. Now, a research team led by Martin Kerschensteiner, Director of the Institute for Clinical Neuroimmunology at LMU, in cooperation with Thomas Misgeld (Technical University of Munich) and Doron Merkler (University of Geneva), has shown in a mouse model that inflammation of the gray matter leads to a decrease in nerve-cell activity, owing to the (potentially reversible) destruction of synapses. "Targeted inhibition of specific types of immune cells can slow synapse damage down, and offers an interesting new therapeutic approach," Kerschensteiner explains.

Loss of synapses - the structures that serve as functional contacts between nerve cells - is an early indicator of damage to the cerebral cortex in cases of progressive MS. The researchers therefore suspected that the synapses are the key to the neuronal damage that ensues in this stage of the disease. With the aid of various imaging techniques, the team was able to demonstrate that such widespread loss of synapses can be reproduced in a mouse model of MS. Moreover, their observations revealed that synaptic spines are destroyed by a specific type of immune cells. "These immune cells preferentially eliminate spines, which contain high levels of calcium. We assume that the inflammation reaction itself triggers an influx of calcium, which destabilizes the spines," says Kerschensteiner. "These changes in late-stage MS are reminiscent of those that can also be observed during the early phases of neurodegeneration," Misgeld adds. 

The disruption of neuronal networks in the brain can be reversible

The activated immune cells primarily attack excitatory synapses, which are responsible for activating other nerve cells. As a consequence, the level of activity in neural networks decreases. "The nerve cells are effectively silenced," says Kerschensteiner. "However, much to our surprise, we discovered that this process is reversible in our model."

As soon as the inflammation is resolved, the normal number of synapses is restored and the neurons once again exhibit their normal patterns of activity. These results contrast with findings in patients with progressive MS, in whom the cerebral cortex is permanently damaged. "Presumably, the mechanisms responsible for recovery cannot come into effect in these patients, because the inflammation is chronic and remains unresolved," says neuropathologist Merkler. "In our model, we induced an acute inflammatory reaction, which is resolved within a few days."

New pharmaceutical agents might be able to specifically inhibit the activation of the immune cells responsible for synapse destruction and could therefore slow the progress of the disease. However, it is crucial that such inhibitors do not completely block the action of these cells, so that they can continue to carry out their essential functions. The authors of the study hope that this concept can help develop therapeutic approaches that will effectively curb the progression of MS.

Mangrove ecosystems are at particular risk of being polluted by plastic carried from rivers to the sea. Fifty-four per cent of mangrove habitat is within 20 km of a river that discharges more than a tonne of plastic waste a year into the ocean, according to a new paper published in the journal Science of the Total Environment. Mangroves in southeast Asia are especially threatened by river-borne plastic pollution, the researchers found.

The paper, written by scientists at GRID-Arendal and the University of Bergen, is the first global assessment of coastal environments' exposure to river-borne plastic pollution. The majority of plastic waste carried to sea by rivers ends up trapped along coastlines, but some types of coastal environments trap much more plastic than others. The researchers overlayed maps of coastal ecosystems with the most current information on the input of river-borne plastic to sea to find out which coastal environments have the potential to be most affected by plastic pollution originating on land.

The study found that river deltas receive 52 per cent of river-borne plastic pollution, though they make up less than 1 per cent of global coastlines. Rocky shores, in contrast, receive only 6 per cent of the plastic pollution, though they make up 73 per cent of global coastlines. No type of coastal environment is unaffected by river-borne plastic pollution.

The authors also assessed the exposure of mangroves, coral reefs, seagrass, and saltmarsh to rivers that discharge high amounts of plastic into the sea, in excess of one tonne per year. Mangroves were the most affected, with 54 per cent of mangrove areas located near at least one of these highly polluting rivers. Coral reefs were the least affected of the four habitats, with just 17 per cent of coral reefs located within 20 km of a river that discharges more than a tonne of plastic pollution a year.

Southeast Asia is more affected by river-borne plastic pollution than any other region in the world. Previous research has estimated that 86 per cent of plastic pollution enters the ocean from Asian rivers. This is one reason why mangroves in southeast Asia are especially vulnerable to plastic pollution. Coral reefs in southeast Asia are also more affected by marine plastic than reefs in most other regions of the globe, the researchers found, while coral reefs in Australia appear to have escaped severe impact from plastic pollution.

"To effectively fight the growing problem of marine plastic pollution, we need to know how plastic waste is distributed and which ecosystems are most affected," said Peter Harris, lead author of the paper and managing director of GRID-Arendal. "Now that we know mangroves have a higher likelihood of being severely affected by plastic waste, leaders can take steps to protect these critical habitats."

The authors of the paper recommend that authorities prioritize reducing plastic pollution in areas where rivers enter the sea near sensitive and protected ecosystems.

FORT LAUDERDALE/DAVIE, Fla. - Global warming or climate change. It doesn't matter what you call it. What matters is that right now it is having a direct and dramatic effect on marine environments across our planet.

"More immediately pressing than future climate change is the increasing frequency and severity of extreme 'underwater heatwaves' that we are already seeing around the world today," Lauren Nadler, Ph.D., who is an assistant professor in Nova Southeastern University's (NSU) Halmos College of Arts and Sciences . "This phenomenon is what we wanted to both simulate and understand."

Nadler is a co-author of a new study on this topic, which you can find published online at eLife Science Journal.

As a way to further document how increasing temperatures in our oceans are impacting marine life, Nadler and a team of researchers collected two common coral reef fishes - the five-lined cardinalfish and the redbelly yellowtail fusilier - from the northern Great Barrier Reef in Australia. Then, under controlled laboratory conditions, the team gradually increased temperatures by 3.0?C above the average summer temperatures for the area. But don't worry, they didn't boil the fish, rather, they increased the temps so they could measure realistically how each species responded to these warmer conditions over a five-week period.

The researchers point out that these underwater heatwaves can cause increases of up to 5?C above seasonal average temperatures over the course of just days and can last for several weeks. This rise in temperature can lead to rapid physiological changes in these reef fishes, which could have long-term effects on survival.

"We found that the fusilier rapidly responded to thermal stress, with nearly immediate changes detected in gill shape and structure and blood parameters, however, the cardinalfish exhibited a delayed response and was far less able to adjust to the elevated temperatures," said Jacob Johansen, Ph.D., a co-author of the study who is an assistant research professor at the University of Hawaii's Hawaii Institute of Marine Biology at Manoa.

"More importantly, we identified seven parameters across both species that may be useful as biomarkers for evaluating how fast and to what extent coral reef fishes can cope with increasing temperatures. Our findings greatly improve our current understanding of physiological responses to ongoing thermal threats and disturbances, including which species may be most at risk," said Johansen.

The research team emphasises that the study is timely, given the rapid decline of tropical coral reefs worldwide, including the repeated mass coral bleaching and mortality events on the Great Barrier Reef in 2016, 2017, and 2020 - all caused by summer heatwaves. Nadler indicated that climate change 'winners and losers' will ultimately be determined by the capacity to compensate for thermal stress in both the short term of days, weeks, and months, such as in response to heatwaves as we have demonstrated, and over the longer term of years, decades, and centuries.

"Our findings are immensely useful for scientists but also for managers, conservation planners, and policy makers charged with protecting important ecosystems, such as coral reefs, as well as communities who rely on coral reefs for food, culture, jobs, and their livelihoods," said Jodie Rummer, Ph.D., an associate professor at James Cook University´s ARC Centre of Excellence for Coral Reef Studies and a co-author of the study. "Collectively, we need to be able to predict which species are going to survive and which will be most vulnerable to climate change so we can take action, as the decisions we make today will determine what coral reefs look like tomorrow."

Scientists have designed a single-dose universal vaccine that could protect against the many forms of leptospirosis bacteria, according to a study published today in eLife.

An effective vaccine would help prevent the life-threatening conditions caused by leptospirosis, such as Weil's disease and lung haemorrhage, which are fatal in 10% and 50% of cases, respectively.

Leptospirosis is caused by a diverse group of spirochetes called leptospires. A broad range of mammals, including rats, harbour the bacteria in their kidneys and release them into the environment through their urine. Humans and animals can then get infected after coming into contact with contaminated water or soil. In addition to having a major impact on the health of vulnerable human populations, leptospirosis is an economically important animal health problem, making it a significant One Health challenge. This means that collaborative efforts are needed across disciplines and sectors to improve public health outcomes against leptospirosis infection.

The Leptospira family of bacteria is made up of 64 species with 300 different varieties (called serovars). This makes developing a vaccine challenging, because researchers need to find a common feature of the bacteria that will trigger an immune response.

"We have recently identified a novel protein called FcpA in the flagella of Leptospira which enables it to move and penetrate human and animal tissues," explains first author Elsio Wunder Jr, Associate Research Scientist in Epidemiology (Microbial Diseases) at Yale School of Public Health, Yale University, New Haven, US. "With this study, we wanted to see whether using engineered Leptospira that lacks a functional FcpA molecule has the potential for a vaccine that could provide major public health benefit."

The mutated FcpA Leptospira was tested as an attenuated vaccine - a live vaccine that cannot cause disease. After the vaccine was given to hamsters and mice, it disseminated throughout the body before being cleared within seven days in the hamsters and after two weeks in the mice. No traces of the mutated Leptospira could be detected in kidney tissue or blood after this time point, showing that the attenuated vaccine is cleared by the immune system before it results in disease or death.

To test whether the vaccine candidate could protect against all types of Leptospira infection, they tested a single dose of the mutant Leptospira and compared this against heat-killed Leptospira to see whether they could prevent infection and disease by a range of similar and different serovars. Immunisation with the heat-killed vaccine gave partial protection against similar serovars but not against different serovars of Leptospira. By contrast, the attenuated vaccine (mutated Leptospira) provided cross-protection against serovars belonging to three different species of Leptospira, which encompass the majority of serovars of importance to human and animal health.

Further analysis of the mice and hamsters after vaccination showed that they generated antibodies that recognised a wide range of proteins across the different species of Leptospira. Moreover, by studying the antibody response in detail, the team identified 41 different proteins that could be targets for future vaccines. The majority of these proteins (70%) looked similar across all 13 disease-causing species of Leptospira studied, suggesting they are likely to be important to the microbes' survival and would make effective future vaccine candidates.

"In this proof-of-concept study, we have shown that a universal leptospirosis vaccine candidate can prevent both death and kidney colonisation in animal models," concludes author Albert Ko, Department Chair and Professor of Epidemiology (Microbial Diseases) at Yale School of Public Health. "These findings take us one step closer to achieving the holy grail for the field, which is an effective vaccine that protects against the many Leptospira species and can be deployed as a broad solution to the human and animal health challenge caused by leptospirosis."

Syracuse, N.Y. - As President Joe Biden seeks to raise the federal minimum wage, a new study published recently by researchers from Syracuse University shows that a higher minimum wage will reduce infant deaths.

In the study, "Effects of US state preemption laws on infant mortality," Syracuse University professors found that each additional dollar of minimum wage reduces infant deaths by up to 1.8 percent annually in large U.S. cities. The study was published recently by Preventive Medicine.

The federal minimum wage has not been increased since 2009, and Biden's $1.9 trillion American Rescue Plan to aid those hit hardest by the COVID-19 pandemic calls for Congress to raise the minimum wage from $7.25 to $15 per hour. Recent attempts to increase the minimum wage have been opposed by states that have prevented city and county governments from raising the minimum wage in their localities.

Research has shown that a higher minimum wage reduces teenage pregnancy, maternal smoking, obesity, and adverse birth outcomes such as low-weight births and infant deaths.

Using data on infant deaths in each county from the 2001-18 National Center for Health Statistics mortality files, and data on minimum wage levels from the U.S. Bureau of Labor Statistics, the researchers examined how many infant lives would have been saved if states had not prevented cities and counties from raising their minimum wages.

Here are their key findings:

States are increasingly preempting city and county governments from enacting policies that benefit workers, such as raising the minimum wage.

Each additional dollar of minimum wage reduces infant deaths by up to 1.8% annually in large U.S. cities.

In the 25 states that preempted minimum wage increases, more than 600 infants could have been saved annually if localities had been allowed to raise their wage to $9.99.

More than 1,400 infants could have been saved annually if localities had been allowed to raise the minimum wage to $15.

State laws that prevent cities and counties from raising their minimum wage contribute to infant deaths.

Opponents of a $15 federal minimum wage say more than one million people may become jobless because of the impact on businesses, with teenagers, part-time workers, and those with only a high school diploma most affected.

"Those opposed to raising the wage worry about a potential rise in unemployment," the researchers concluded in their study. "Any such effect on unemployment should be weighed against the benefits of lifting people out of poverty and saving infant lives via more livable wages.

"Keeping the minimum wage low may protect business profits and keep prices lower for consumers," the researchers said, "but our results suggest that the tradeoff in human lives is steep."

Researchers from McGill University have discovered, for the first time, one of the possible mechanisms that contributes to the ability of lysergic acid diethylamide (LSD) to increase social interaction. The findings, which could help unlock potential therapeutic applications in treating certain psychiatric diseases, including anxiety and alcohol use disorders, are published in the journal PNAS.

Psychedelic drugs, including LSD, were popular in the 1970s and have been gaining popularity over the past decade, with reports of young professionals claiming to regularly take small non-hallucinogenic micro-doses of LSD to boost their productivity and creativity and to increase their empathy. The mechanism of action of LSD on the brain, however, has remained a mystery.

Studies in mice provide clues

To conduct their study, the researchers administered a low dose of LSD to mice over a period of seven days, resulting in an observable increase in the sociability of the mice. "This increased sociability occurs because the LSD activates the serotonin 5-HT2A receptors and the AMPA receptors -- which is a glutamate receptor, the main brain excitatory neurotransmitters -- in the prefrontal cortex and also activates a cellular protein called mTORC 1," explains Danilo De Gregorio, PharmD, PhD, who is a postdoctoral fellow in the Neurobiological Psychiatry Unit at McGill and the study's first author. "These three factors, taken together, promote social interaction in mice, which is the equivalent of empathy and social behaviour in humans."

The researchers note that the main outcome of their study is the ability to describe, at least in rodents, the underlying mechanism for the behavioural effect that results in LSD increasing feelings of empathy, including a greater connection to the world and sense of being part of a large community. "The fact that LSD binds the 5-HT2A receptor was previously known. The novelty of this research is to have identified that the prosocial effects of LSD activate the 5-HT2 receptors, which in-turn activate the excitatory synapses of the AMPA receptor as well as the protein complex mTORC1, which has been demonstrated to be dysregulated in diseases with social deficits such as autism spectrum disorder," as specified by Prof. Nahum Sonenberg, Professor at the Department of Biochemistry of McGill University, world renowned expert in the molecular biology of diseases and co-lead author of the study.

Using the cutting-edge technique of optogenetics, a technique where genes for light-sensitive proteins are introduced into specific types of brain cells in order to monitor and control their activity precisely using light signals, the researchers observed that when the excitatory transmission in the prefrontal cortex is de-activated, the prosocial effect of LSD was nullified, highlighting the importance of this brain region on the modulation of the behavioural effects of LSD.

Moving forward to apply the findings to humans

Having found that LSD increases social interaction in mice, the researchers are hoping to continue their work and to test the ability of LSD to treat mutant mice displaying the behavioural deficits similar to those seen in human pathologies including autism spectrum disorders and social anxiety disorders. The hope is to eventually explore whether micro-doses of LSD or some novel derivates might have a similar effect in humans and whether it could also be a viable and safe therapeutic option.

"Social interaction is a fundamental characteristic of human behaviour," notes the co-lead author Dr. Gabriella Gobbi, Professor in the Department of Psychiatry at McGill and psychiatrist at the McGill University Health Centre. "These hallucinogenic compounds, which, at low doses, are able to increase sociability may help to better understand the pharmacology and neurobiology of social behavior and, ultimately, to develop and discover novel and safer drugs for mental disorders."

Black holes are considered amongst the most mysterious objects in the universe. Part of their intrigue arises from the fact that they are actually amongst the simplest solutions to Einstein's field equations of general relativity. In fact, black holes can be fully characterized by only three physical quantities: their mass, spin and charge. Since they have no additional "hairy" attributes to distinguish them, black holes are said to have "no hair": Black holes of the same mass, spin, and charge are exactly identical to each other.

Dr. Lior Burko of Theiss Research in collaboration with Professor Gaurav Khanna of the University of Massachusetts Dartmouth and the University of Rhode Island alongside his former student Dr. Subir Sabharwal discovered that a special kind of black hole violates black hole uniqueness, the so-called "no hair" theorem. Specifically, the team studied extremal black holes -- holes that are "saturated" with the maximum charge or spin they can possibly carry. They found that there is a quantity that can be constructed from the spacetime curvature at the black hole horizon that is conserved, and measurable by a distant observer. Since this quantity depends on how the black hole was formed, and not just on the three classical attributes, it violates black hole uniqueness.

This quantity constitutes "gravitational hair" and potentially measurable by recent and upcoming gravitational wave observatories like LIGO and LISA. The structure of this new hair follows the development of a similar quantity that was found by Angelopoulos, Aretakis, and Gajic in the context of a simpler "toy" model using a scalar field and spherical black holes, and extends it to gravitational perturbations of rotating ones.

"This new result is surprising," said Burko, "because the black hole uniqueness theorems are well established, and in particular their extension to extreme black holes. There has to be an assumption of the theorems that is not satisfied, to explain how the theorems do not apply in this case." Indeed, the team followed on previous work by Aretakis, that found that even though external perturbations of extreme black holes decay as they do also for regular black holes, along the event horizon certain perturbation fields evolve in time indefinitely. "The uniqueness theorems assume time independence. But the Aretakis phenomenon explicitly violates time independence along the event horizon. This is the loophole through which the hair can pop out and be combed at a great distance by a gravitational wave observatory," said Burko. Unlike other work that found hair in black hole scalarization, Burko noted that "in this work we were working with the vacuum Einstein theory, without additional dynamical fields that modify the theory and which may violate the Strong Equivalence Principle."

The team used very intensive numerical simulations to generate their results. The simulations involved using dozens of the highest-end Nvidia graphics-processing-units (GPUs) with over 5,000 cores each, in parallel. "Each of these GPUs can perform as many as 7 trillion calculations per second; however, even with such computational capacity the simulations look many weeks to complete," said Khanna.

Landslides caused by the collapse of unstable volcanoes are one of the major dangers of volcanic eruptions. A method to detect long-term movements of these mountains using satellite images could help identify previously overlooked instability at some volcanoes, according to Penn State scientists.

"Whenever there is a large volcanic eruption, there is a chance that if a flank of the volcano is unstable there could be a collapse," said Judit Gonzalez-Santana, a doctoral student in the Department of Geosciences. "To better explore this hazard, we applied an increasingly popular and more sensitive time-series method to look at these movements, or surface deformation, over longer time periods."

Using the time-series technique, the scientists found surface deformation related to flank motion had occurred at Pacaya, an active volcano in Guatemala, from 2011 to 2013 when the volcano was largely quiet, and increased leading up to an eruption in 2014. Previous work had not identified flank motion during this time, the scientists said.

"People have looked at that volcano with satellite remote sensing but did not detect this long-term flank motion or creep," said Christelle Wauthier, associate professor of geosciences. "Because the surface deformation changes are pretty small per year, it can easily be below the detection limits of conventional methods, but still within the limits of Judit's work using a time-series approach."

Scientists track surface deformation using radar satellites sensitive enough to spot changes of just a few inches on the ground. Comparing two of these images using the conventional Interferometric Synthetic Aperture Radar (InSAR) technique creates an interferogram, essentially a map of surface movement. But the quality of the InSAR results decreases with the time separating two images and can be affected by even small changes, like from vegetation growth or a buildup of ash spewed from a volcano, the scientists said.

The team instead conducted an InSAR time-series analysis using hundreds of satellite images taken over years and identifying surface deformation between each.

"You can use many of these short-term surface movement maps to give you information of surface displacement over a long time period," Gonzalez-Santana said. "Then you can look at the surface deformation maps and see how much each pixel has been moving since the date the first image was acquired, for example."

The results, published in the Journal of Volcanology and Geothermal Research, provide finer detail of volcanic flank motion, and can reveal upticks in the rate that creep is occurring, like at Pacaya before the eruption in 2014, the scientists said. The team has shared the results with officials in Guatemala who monitor the volcano.

"This kind of creep is not uncommon and not particularly dangerous on its own, but if you have extra forcings like from magma being pressurized and pushing against the wall of the chamber or intrusion, it can trigger a catastrophic collapse," Wauthier said. "To be able to understand the behavior of the instability and potentially detect changes in rates of motion is very critical for monitoring that potential collapse."

The method shows promise for identifying deformation particularly at volcanoes that lack expensive real-time monitoring networks and those located in tropical areas with thick vegetation that create problems for traditional InSAR, the scientists said.

Flank instability is often studied at oceanic volcanoes, where a collapse could trigger a deadly tsunami, according to the scientists. But collapses also happen inland, including prominently at Mount St. Helens in 1980.

Pacaya itself experienced a collapse sometime around 1,000 years ago, creating a debris avalanche that traveled more than 15 miles, and leaving a prominent scar on the volcano. Subsequent eruptions have built the volcano back up and it could someday again collapse, the scientists said.

"More than 10,000 people live within about three miles of the volcano," Gonzalez-Santana said. "If you take into consideration the last avalanche traveled 15 miles away, anyone living in the valleys around the volcano could be at risk."

Corn hasn't always been the sweet, juicy delight that we know today. And, without adapting to a rapidly changing climate, it is at risk of losing its place as a food staple. Putting together a plant is a genetic puzzle, with hundreds of genes working together as it grows. Cold Spring Harbor Laboratory (CSHL) Professor David Jackson worked with Associate Professor Jesse Gillis to study genes involved in corn development. Their teams analyzed thousands of individual cells that make up the developing corn ear. They created the first anatomical map that shows where and when important genes turn on and off during key steps in development. This map is an important tool for growing better crops.

Humans have been breeding corn to make it more useful for thousands of years. Jackson says:

"Ten thousand years ago, corn did not exist, right? There was a wild plant called teosinte. Teosinte itself only makes about 10 seeds. It makes these really tiny ears that don't give much nutrition. In fact, the seeds they make are so tough that they would break your teeth if you try to eat them anyway."

The secret to more and bigger kernels is found by looking at baby ears of corn 1-10 mm long. The scientists used a technique that allowed them to track every cell. They gave each cell a genetic ID tag, called a barcode. Xiaosa Xu, the lead author of the study, compares it to building a building. Xu says:

"We are able to use this single-cell RNA-seq technology to identify which block is what kind of identity: if this block is from our kitchen room or that block is from our bedroom."

The scientists took corn plants at early stages of development, broke them into individual cells, barcoded them, and then saw what genes were turned on in each one. Jackson notes, "in the past we haven't been able to separate the cells and figure out the genetic information that's specific to each cell. So that's really, what's new and exciting." They could then reconstruct an anatomical map to pinpoint where genes important for corn development were used.

Crops are still evolving. Jackson looks forward to developing different kinds of corn plants to fill new ecological niches. He also hopes this new technique will help other plant geneticists in their efforts to sustainably improve crop yields.

The health of aquatic ecosystems depends on the supply of key nutrients, especially phosphorus. Too much phosphorus results in unwanted eutrophication, and much effort is spent on preventing phosphorus pollution of water bodies. In the World's largest freshwater ecosystem, the North American Great Lakes, this control may have recently been lost to an invasive species. According to a new study, quagga mussels, which have spread across four of the five Great Lakes, have accumulated large amounts of phosphorus in their biomass, to the degree that their activities now regulate the supply of phosphorus to the ecosystem.

The invaders, native to the Ponto-Caspian region of Eurasia, appeared in the Great Lakes in the late 1980's and by late 2000's spread over vast areas of bottom sediments in all the lakes except Lake Superior. Their biological effects on the ecosystem have been well recognized, but effects on the chemical system remained uncertain.

Researchers from the Large Lakes Observatory, University of Minnesota Duluth analyzed the cycling of phosphorus in lakes Michigan, Huron, Erie, and Ontario. They used a mass-balance model, which they calibrated with measurements that the team performed on sediments and mussels at multiple locations in Lakes Michigan and Huron. The results show that the concentrations of phosphorus in the invaded Great Lakes are now regulated by the population dynamics of a single benthic species, the quagga mussel.

"Quagga mussels are small, hard-shelled organisms that live on the lake floor and filter the water, removing the phytoplankton and other small particles," explains Ted Ozersky, an Associate Professor of Biology who co-led the study. By now they occupy the lake floor at densities often exceeding 10,000 individuals per square meter (6 mussels per square inch). "In terms of biomass, quagga mussels are the dominant life form in the Great Lakes," says Sergei Katsev, a Professor at the Large Lakes Observatory who oversaw the geochemical aspects of the research.

By filtering organic particles from the lake water and recycling phosphorus back with their excretions and feces, mussels dramatically alter the natural rates at which phosphorus is exchanged between lake water and sediments. According to the study, the mussels in Lake Michigan are not only removing phosphorus from the water ten times faster than two decades ago, but are also resupplying the water column with eight times the amount of phosphorus that reaches the lake from the entire watershed. This kind of "internal loading" effectively decouples the dynamics of phosphorus from watershed inputs, leaving the system open to poorly predictable fluctuations when mussel populations increase or decrease.

"The mussels have short-circuited the normal pathways of the phosphorus cycling in the lakes," explains the lead author Jiying Li, formerly a postdoctoral researcher at UMD and presently an Assistant Professor at the Hong Kong University of Science and Technology. "And the productivity in the lakes is now tied to what the mussel populations are doing."

Growing populations of mussels are capable of absorbing large quantities of phosphorus from the water column, which is partly responsible for the water in the Great Lakes becoming clearer over recent years. In contrast, mortality events are capable of releasing large quantities of phosphorus back into the ecosystem. As a result, phosphorus becomes regulated by the dynamics of mussel populations and may respond only slowly to our efforts to control the runoff of phosphorus from the watershed.

The results of the study, which appears in this week's PNAS, show that a single invasive species can have dramatic consequences for geochemical cycles even in the world's largest aquatic ecosystems. According to the authors, this forewarns of similar ecological changes in mussel-invaded lakes across Europe and North America and calls for a new paradigm for managing aquatic ecosystems.

Their field may not be top of mind among those that contribute to the greater good, yet new research from the University of Notre Dame shows marketers can help entrepreneurs in emerging markets grow their businesses, which in turn helps them to improve lives, sustain livelihoods, enhance overall living standards and strengthen societies.

"Do Marketers Matter for Entrepreneurs? Evidence from a Field Experiment in Uganda" is forthcoming in the Journal of Marketing from Frank Germann, an associate professor of marketing at Notre Dame's Mendoza College of Business who teaches core marketing courses in the Notre Dame MBA program.

Germann, along with Stephen Anderson from the University of Texas at Austin, Pradeep Chintagunta from the University of Chicago and Naufel Vilcassim from the London School of Economics, conducted a randomized, controlled field experiment with 930 Ugandan businesses that were aided by international business support volunteers including marketers from more than 60 countries.

"Volunteer marketers helped entrepreneurs grow sales, profits, assets and employees," Germann said. "Specifically, compared to control firms, the supported entrepreneurs grew monthly sales by 52 percent on average, while their monthly profits improved by 36 percent, total assets rose by 31 percent and the number of paid employees increased by 24 percent."

Entrepreneurs are ubiquitous in emerging markets. In 2010, more than 31 percent of the adult population in Uganda was either starting a business or running a business less than four years old. "However," Germann pointed out, "many emerging market entrepreneurs struggle to make ends meet, and their firms' growth rates are low, stifling the positive impact they could have on society."

Prior studies have shown the low growth rates appear to result from most businesses being too similar and failing to attract customer interest. "Marketing helps firms to differentiate by focusing on the question, 'Why should the customer buy from the firm and not elsewhere?'" Germann said.

"A bake shop owner in our marketer treatment group began selling high-quality doughnuts to a local supermarket," he said. "She placed a display unit in the market, which helped differentiate her firm as a quality bake shop and attracted additional business opportunities. Also, a beauty salon owner in the sample trained herself to offer new and sought-after hairstyles. She now also sells and applies hair extensions in various colors and styles, allowing her to stand out from competitors offering only basic services."

An analysis of interactions between volunteers and entrepreneurs revealed that the marketers spent more time on product-related topics than other volunteers and helped put the focus on premium products to differentiate businesses in the marketplace. Firms with greater market knowledge or resource availability benefited significantly more than their peers when matched with volunteer marketers.

"Small-scale businesses form the commercial backbone of most emerging markets, so their performance and development are critically important," Germann added. "Research indicates entrepreneurship is one of the most effective means to alleviate poverty in developing countries."

The team hopes its study will motivate marketing practitioners to work with entrepreneurs and early-stage ventures in emerging markets and encourage business schools to incorporate versions of their "remote coaching" intervention into emerging market programs, with a focus on matching entrepreneurs with their marketing students.

Germann says organizations actively serving emerging markets should also benefit from their findings when designing and implementing future business support services delivered in emerging markets.

Providing economic relief to struggling families can lead to another positive effect -- fewer cases of child neglect, according to new research by the University of Washington.

A 10% increase in a common benefit for low- to moderate-income working families, the Earned Income Tax Credit, led to a 9% decrease in the annual number of reports of child neglect made to child welfare agencies over a 14-year study period. That's a significant impact, researchers say, and can inform future social policies.

The study is relevant to current policy actions, as President Joe Biden has recently proposed an expansion of the child tax credit as part of his new stimulus plan.

"The EITC is an important part of the U.S. safety net that has been shown to substantially reduce child poverty. Our results add to growing evidence that policies that improve family economic security can also prevent child maltreatment," said Nicole Kovski, a doctoral student at the Evans School of Public Policy and Governance at the UW.

She is lead author of the study published Jan. 19 in the journal Child Maltreatment.

Child maltreatment is a common problem in the United States, with an estimated one-third of children subject to a child protective services investigation before they turn 18.

The stress of poverty has long been linked to child abuse and family instability, and other research has explored the impact of different economic policies on child-abuse prevention. The UW study is the first to focus on the Earned Income Tax Credit - a program designed to assist lower-income families, often with a tangible benefit in the form of a tax refund - and its potential association with reports of child maltreatment made to child welfare agencies across the U.S.

The Earned Income Tax Credit is provided by both the federal government and 28 states, and eligibility and credit size vary with income and family size. UW researchers focused on the generosity of refundable state EITCs, noting that such a benefit has been found to be put toward a family's basic needs.

The research team analyzed the number of child abuse and neglect reports to local and state agencies from 2004 through 2017 and the correlation with the EITC program at the state level. The team hypothesized that the more generous a state's EITC, the more necessities, such as child care or rent, a family can put the money toward, potentially alleviating some of the stress that can lead to child maltreatment. Over the course of the study period, many states altered their level of benefit as a percentage of the federal tax credit, while others generally held steady. Minnesota, for example, provided an average of 33% of the federal credit, depending on household income, while Oklahoma provided 5% of the federal credit before making its EITC nonrefundable in 2016.

With the child abuse and neglect data, the UW team counted all reports of maltreatment, rather than just those reports that were found to be substantiated, reasoning that any report increases the likelihood of a child being victimized in the future. Taking all states into account - those with and without an EITC -- during the study period, states averaged nearly 4,400 maltreatment reports per 100,000 children each year.

When annual state EITC benefits were taken into account, the team found maltreatment reports, particularly those of neglect, declined as benefit levels rose: A 10 percentage-point increase in state-level benefits was associated with 241 fewer reports of neglect per 100,000 children. The effect was even more pronounced in the number of neglect reports on children from infancy through age 5, the age range at which the majority of maltreatment incidents occur.

Put another way, a 10 percentage-point increase in the refundable EITC benefit led to a 9% drop in rates of reported child neglect.

"This study highlights the importance of investigating the impact of social policies on health. Violence is a health issue with multiple forms, such as child maltreatment. An emerging body of evidence is empirically demonstrating that violence prevention can be an added benefit of social policies that were not necessarily enacted with that specific goal originally. This study is the most recent addition to that literature," said Ali Rowhani-Rahbar, an associate professor of epidemiology at the UW, director of the Violence Prevention Section at the Harborview Injury Prevention and Research Center, and the principal investigator of the project that supported this study.

While child neglect showed a trend, the link between EITC benefits and reports of specific types of abuse - physical, sexual and emotional - was not statistically significant. Researchers note that child abuse rates, in general, have declined much more significantly than neglect rates in recent decades, while neglect is found in three-quarters of child maltreatment cases.

Child neglect, too, may be more distinctly associated with poverty, past research has shown, potentially making some interventions more effective in preventing certain types of maltreatment than others.

"Child neglect often involves the failure of a caregiver to provide children with necessities, such as food, shelter and basic supervision. Additional income provided to families through the EITC can improve parents' abilities to meet these basic needs," Kovski said.

Researchers say the findings point to the fundamental value of an economic policy - the EITC - as a child-maltreatment prevention strategy. In other words, proactively improving financial stability among families may mitigate the circumstances that lead to child neglect and abuse.

RESEARCH TRIANGLE PARK, N.C. -- Kombucha tea, a trendy fermented beverage, inspired researchers to develop a new way to generate tough, functional materials using a mixture of bacteria and yeast similar to the kombucha mother used to ferment tea.

With Army funding, using this mixture, also called a SCOBY, or symbiotic culture of bacteria and yeast, engineers at MIT and Imperial College London produced cellulose embedded with enzymes that can perform a variety of functions, such as sensing environmental pollutants and self-healing materials.

The team also showed that they could incorporate yeast directly into the cellulose, creating living materials that could be used to purify water for Soldiers in the field or make smart packaging materials that can detect damage.

"This work provides insights into how synthetic biology approaches can harness the design of biotic-abiotic interfaces with biological organization over multiple length scales," said Dr. Dawanne Poree, program manager, Army Research Office, an element of the U.S. Army Combat Capabilities Development Command, now known as DEVCOM, Army Research Laboratory. "This is important to the Army as this can lead to new materials with potential applications in microbial fuel cells, sense and respond systems, and self-reporting and self-repairing materials."

The research, published in Nature Materials was funded by ARO and the Army's Institute for Soldier Nanotechnologies at the Massachusetts Institute of Technology. The U.S. Army established the ISN in 2002 as an interdisciplinary research center devoted to dramatically improving the protection, survivability, and mission capabilities of the Soldier and Soldier-supporting platforms and systems.

"We foresee a future where diverse materials could be grown at home or in local production facilities, using biology rather than resource-intensive centralized manufacturing," said Timothy Lu, an MIT associate professor of electrical engineering and computer science and of biological engineering.

Researchers produced cellulose embedded with enzymes, creating living materials that could be used to purify water for Soldiers in the field or make smart packaging materials that can detect damage.
These fermentation factories, which usually contain one species of bacteria and one or more yeast species, produce ethanol, cellulose, and acetic acid that gives kombucha tea its distinctive flavor.

Most of the wild yeast strains used for fermentation are difficult to genetically modify, so the researchers replaced them with a strain of laboratory yeast called Saccharomyces cerevisiae. They combined the yeast with a type of bacteria called Komagataeibacter rhaeticus that their collaborators at Imperial College London had previously isolated from a kombucha mother. This species can produce large quantities of cellulose.

Because the researchers used a laboratory strain of yeast, they could engineer the cells to do any of the things that lab yeast can do, such as producing enzymes that glow in the dark, or sensing pollutants or pathogens in the environment. The yeast can also be programmed so that they can break down pollutants/pathogens after detecting them, which is highly relevant to Army for chem/bio defense applications.

"Our community believes that living materials could provide the most effective sensing of chem/bio warfare agents, especially those of unknown genetics and chemistry," said Dr. Jim Burgess ISN program manager for ARO.

The bacteria in the culture produced large-scale quantities of tough cellulose that served as a scaffold. The researchers designed their system so that they can control whether the yeast themselves, or just the enzymes that they produce, are incorporated into the cellulose structure. It takes only a few days to grow the material, and if left long enough, it can thicken to occupy a space as large as a bathtub.

"We think this is a good system that is very cheap and very easy to make in very large quantities," said MIT graduate student and the paper's lead author, Tzu-Chieh Tang.
To demonstrate the potential of their microbe culture, which they call Syn-SCOBY, the researchers created a material incorporating yeast that senses estradiol, which is sometimes found as an environmental pollutant. In another version, they used a strain of yeast that produces a glowing protein called luciferase when exposed to blue light. These yeasts could be swapped out for other strains that detect other pollutants, metals, or pathogens.

The researchers are now looking into using the Syn-SCOBY system for biomedical or food applications. For example, engineering the yeast cells to produce antimicrobials or proteins that could benefit human health.

Since the founding of the United Nations Convention on Biological Diversity (CBD) in Rio de Janeiro in 1992, member states have regularly agreed on global strategies to bring the increasingly rapid loss of biodiversity to a halt. In 2002, the heads of state adopted the so-called 2010 biodiversity targets. Eight years later, little progress had been made and 20 new, even more ambitious goals were set for the next ten years. Last year, it became clear that this target had been missed, too. The loss of biodiversity continues unabated.

This year, new targets are being negotiated again - this time for 2030. The decisions are to be made at the Conference of the Parties (COP15) in Kunming, China. To ensure that the mistakes from previous years will not be repeated, Chinese researchers led by Prof Haigen Xu from the Nanjing Institute for Environmental Research in cooperation with Prof Henrique Pereira (iDiv, MLU) have presented an analysis of the causes of this failure, focusing primarily on implementation in the individual member states.

Their conclusion: the commitments at UN level were all too seldom transposed into national law. Four of the 20 so-called Aichi Targets are not reflected in any of the implementation plans (NBSAPs) submitted by the governments, including the phasing out of environmentally harmful subsidies. The other targets were formulated strictly enough to meet the requirements of the CBD decisions in only 22 percent of the NBSAPs. In addition, the analysis revealed insufficient financial resources and major gaps in knowledge on how to record and effectively combat biodiversity loss. Implementation of the promised goals in member states was insufficiently monitored, as effective indicators and evaluation mechanisms were lacking in some cases.

"While the CBD has now presented a first post-2020 draft that contains many improvements compared to the last decade's Strategic Plan for Biodiversity," says ecologist and last author Pereira, "the main problems remain: governments are not required to present a clear roadmap on how they will achieve and monitor the targets adopted under the CBD in their own countries."

The authors suggest that the CBD targets should be formulated in such a way that they can be transposed into national law as a mandatory minimum requirement. Similar to the Paris Climate Agreement or the Washington Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), the CBD targets should be legally binding. Financial resources to promote biodiversity should be significantly increased and new instruments such as payments for ecosystem services and biodiversity-related taxes should be introduced. In addition, interdisciplinary research on the status, trends and drivers of biodiversity loss worldwide should be strengthened and appropriately equipped in order to develop the necessary responses. Further, the CBD should establish a mechanism to verify the compliance of member states with their targets and, if necessary, hold them accountable.

Pereira and several other colleagues at iDiv are actively contributing to biodiversity-related policy processes at various levels, for example, within the framework of the United Nations in the World Biodiversity Council IPBES and the CBD, at EU level in the negotiations of the Common Agricultural Policy (CAP) and the EU Biodiversity Strategy, as well as in national, regional and local contexts. These activities are supported by the research centre's good network of collaborators from different disciplines around the world.

Pereira is pleased about this collaboration with his Chinese co-authors as important players in nature conservation from one of the world's most influential nations. "It's inspiring to co-author such an ambitious proposal with colleagues from the host nation of COP15, where the final decisions will be made."