Culture

Misfiring brain cells that control key parts of the mouth and tongue may be creating swallowing difficulties in children with neurodevelopmental disorders, according to neuroscientists with Virginia Tech and George Washington University.

In research using a mouse model of a genetic childhood disorder known as DiGeorge syndrome, scientists found brain cells called motor neurons that directly control the tongue muscles were firing spontaneously, out of sync with the mechanisms that should control their activity.

Finding ways to calm the motor neurons responsible for moving the tongue could lead to improved function in very young children who have difficulty swallowing, eating, or making sounds, but the scientists said more research is needed before developing therapies.

"We are continuing to make the case that activity of the motor neurons that command the movement of key parts of the mouth, tongue, and pharynx are disrupted by the same mechanisms causing genetic neurodevelopmental disorders," said Anthony-Samuel LaMantia, senior co-author of the study, a developmental neurobiologist, and a professor at the Fralin Biomedical Research Institute at VTC. "Our goal is to learn about the causes of these symptoms to help children as early in life as possible."

The study was published online in advance in eNeuro, an open-access journal of the Society for Neuroscience.

Problems ingesting, chewing, or swallowing food occur in up to 80 percent of children with developmental disorders and can lead to food aspiration, choking, or life-threatening respiratory infections.

Suckling, feeding, and swallowing difficulties -- known as pediatric dysphagia -- are among the most serious and frequent complications in infants. They are common in DiGeorge syndrome, which is a genetic disease caused when a small part of chromosome 22 is missing. The syndrome carries a high risk for autism spectrum disorder and schizophrenia, as well as heart, face, and limb malformations.

In the study, associate research professor Xin Wang and co-senior author David Mendelowitz, vice chair and professor of pharmacology and physiology, both with the George Washington University School of Medicine and Health Sciences, traced the motor neurons in mouse models DiGeorge syndrome from their target muscles, labeled each class of motor neuron, and recorded their electrical properties.

The motor neurons responsible for the forward and backward movement of the tongue in the DiGeorge syndrome models spontaneously fired compared with motor neurons of normal mice, and the excitatory impulses were not balanced by inhibitory responses.

As a result, the increased excitability of motor neurons affected compression and movement of the tongue muscles, which would threaten both food intake efficiency and airway safety in infants and toddlers.

New insight on how an enzyme ensures the correct growth of pollen tubes in flowering plants has been published today in the open-access journal eLife.

The study reveals an unexpected role of KATANIN in moderating the mechanical properties of the papilla cell wall in Arabidopsis thaliana (A. thaliana), thereby preventing disordered pollen tube growth and allowing the tube to find its correct path to the underlying female plant tissues. These findings suggest that KATANIN has likely played a major role in the success of flowering plants on earth more widely.

Seeds are produced in flowering plants when male and female germ cells called gametes fuse together. Male gametes are contained in the pollen grain while female gametes are found in the ovules, which are embedded in a female reproductive organ called the pistil. For successful seed production to happen, pollen grains need to meet with the surface of the pistil, which is composed of a layer of elongated cells called papillae. When a pollen grain lands on a papilla, it rehydrates and then produces a tube that will carry the male gametes toward the ovules.

Pollen tubes grow first within the papilla cell wall, exerting a physical pressure on the cell. After crossing the papilla layer, they then grow in the intercellular space of underlying tissues. The pistil then produces compounds that guide the pollen tube to the ovules where it reaches the female gametes. But how the tube orients itself when it emerges from the pollen at the papilla surface remains unknown.

"It is striking that, whatever the position of the flower and hence the pistil on the stem, the pollen tube grows to the base of the papilla in the direction of the ovules. We wanted to explore the mechanisms that allow for this proper orientation of pollen tubes on the papilla cells," says lead author Lucie Riglet, who was a PhD student in senior author Thierry Gaude's lab at the Laboratory of Plant Reproduction and Development, ENS Lyon, France, at the time the study was carried out, and is now a postdoctoral researcher at the Sainsbury Laboratory, University of Cambridge, UK.

Mechanical forces are known to play a major role in plant cell shape by controlling the orientation of cortical microtubules, which in turn mediate the deposition of cellulose microfibrils. For their study, Riglet and her team combined imaging, genetic and chemical approaches to show that the enzyme KATANIN, which cuts microtubules, also acts on cellulose microfibril orientation and confers mechanical properties to the papilla cell wall that allow for correct pollen tube orientation.

"By forcing the pollen tubes to take the right direction from their early places in the papilla, KATANIN has likely played a major role in the success of flowering plants on earth by promoting fertilisation," explains senior author Thierry Gaude, Group Leader at the Laboratory of Plant Reproduction and Development, ENS Lyon. "As KATANIN is found in most organisms, including humans, it is possible that the enzyme plays a role in regulating mechanical properties in other processes - but this is a fascinating question that remains to be explored."

Population bottlenecks contribute to the accumulation of several harmful mutations that cause age-related illnesses in killifish - a finding that may help answer a key question about aging.

The study, published today in eLife, reveals why killifish accumulate harmful mutations that cause age-related conditions such as cancer or neurodegenerative diseases that shorten lifespan. This may help scientists better understand how lifespan evolves among populations and may lead to new insights on human aging.

The very short lives of turquoise killifish - between three and nine months - make them an ideal model for studying aging. Killifish live in temporary ponds in Africa that dry up for part of the year, meaning they must hatch, mature and reproduce before this happens. Their eggs survive the dry periods in a hibernation-like state and hatch when rains fill the pond again, starting a new generation.

"Different wild turquoise killifish populations have varying lifespans, and we wanted to explore the reasons behind this," explains lead author David Willemsen, Postdoctoral Research Fellow at the Max Planck Institute for Biology of Ageing, Cologne, Germany.

For their study, Willemsen and senior author Dario Riccardo Valenzano carried out field work in savanna pools in Zimbabwe to catch and collect genome samples from the killifish for sequencing and analysing in the lab. The team then compared the genomes of killifish living in the driest environments, which have the shortest lives, with the genomes of killifish from wetter environments, which live for months longer.

The short-lived killifish have very small, often isolated populations, leading to so-called population bottlenecks which, the team found, result in harmful mutations accumulating in their populations. By contrast, the longer-lived killifish have larger populations and new fish with new genetic material frequently join their populations. Over time, these larger populations make it more efficient for natural selection to remove harmful mutations.

"Limited population sizes caused by habitat fragmentation and repeated population bottlenecks increase the chance for harmful mutations to accumulate in the population," Willemsen says. "Our work may help answer a key question about aging by suggesting that population dynamics, rather than evolutionary selection for or against specific genes, contribute to this accumulation of harmful mutations that result in aging and shorter life."

The results support a model where, given the brief rainy seasons, killifish are under strong selective constraints to survive in the absence of water as dormant embryos and to rapidly reach sexual maturation and reproduce before the water completely evaporates. However, the team believes that killifish are not selected to be short-lived. Instead, harmful mutations that affect late-life survival and reproduction (together causing aging in the killifish) accumulate over generations without being constrained by selection.

"Harmful mutations passively accumulate in killifish populations, and this is even more prominent in smaller populations which happen to live in drier environments," says senior author Dario Riccardo Valenzano, Group Leader at the Max Planck Institute for Biology and Ageing, and Principle Investigator at CECAD, the Cluster of Excellence for Ageing Research at the University of Cologne, Germany. "Our findings highlight the role of demographic constraints in shaping lifespan within species and could potentially be expanded to provide new insights on aging within other animal and human populations."

COLUMBIA, SC - September 1, 2020 - The University of South Carolina (UofSC) College of Engineering and Computing will transform the manufacturing and simulation processes used in aircraft production through a $5.7 million NASA grant. The research team's atom to airframe to spaceframe approach will make urban air mobility possible by dramatically increasing the production rate of aircraft.

Ranging from drone delivery services to air metro services to air taxis, urban air mobility refers to in-air transportation within urban areas. It is expected to be a commercially viable market by 2030. However, this will require aircraft to be built in much higher quantities and frequencies than currently being produced.

Today, high-selling aircraft like the Boeing MAXX and the Airbus A321 can be produced at a rate of 60 to 70 aircraft a month, or two to three aircraft a day. Michel van Tooren, the initiator of the NASA proposal and the former director of UofSC's SmartState Center for Multifunctional Materials and Structures, predicts that urban air transport will ultimately require 100 aircraft to be produced a day.

"How do you do that?" van Tooren says. "And if you do 100 aircraft a day and it's maybe 30 blades on an aircraft, then that's 3,000 blades a day. There's no technology available at the moment that creates such an enormous number of aircraft-quality products, and that's the big challenge."

The South Carolina team - in partnership with Boise State University, The University of Southern Mississippi, Benedict College and multiple industry partners - will work to make these production demands possible through a four-year NASA University Leadership Initiative (ULI) grant. South Carolina's research team consists of Darun Barazanchy, Wout De Backer, Jaspreet Pandher and Paul Ziehl, who coordinates and serves as the principal investigator for the project.

"In an impressively short period, the UofSC McNair Aerospace Center has become a household name in the aerospace composites world, especially in the area of thermoplastics and fastener-free joining, as well as robotics, digital commissioning, combustion and predictive maintenance," says Hossein Haj-Hariri, dean of the College of Engineering and Computing. "Receiving one of the coveted NASA ULIs is testimony to the excellence of the center, which continues to pursue and receive similarly competitive and prestigious funding in all its areas, and educates, trains and produces graduates that are at the forefront of their respective disciplines, and highly sought as a result."

Boise State and Southern Mississippi will begin the research using experimental and simulation techniques to make the thermoplastic tape that aircraft are built from stronger and more durable. This tape will then be passed to South Carolina's team, which will use advanced manufacturing processes such as automated fiber placement and automated tape layup to build aircraft parts at a higher production rate. The UofSC team will then use thermoplastic welding, instead of nuts and bolts, to fusion bond the parts together.

"It's a new level of simulation and it's a new way of manufacturing," van Tooren says. "Through it, we can transform aerospace manufacturing and open the door to large-scale urban air mobility sooner than we ever imagined."

The University Leadership Initiative was created by the NASA Aeronautics Research Mission Directorate (ARMD). This $32.8 million ULI has five team leads, including South Carolina, North Carolina Agricultural and Technical State University, Oklahoma State University, Stanford University and the University of Delaware. The ULI will allow these universities to build their own teams and formulate their own research paths in hopes that their findings support the NASA ARMD portfolio and the larger U.S. aviation community.

ITHACA, N.Y. - A new study in mice helps explain why gut microbiomes of breastfed infants can differ greatly from those of formula-fed infants.

The study, "Dietary Sphinganine Is Selectively Assimilated by Members of the Mammalian Gut Microbiome," was published in July in the Journal of Lipid Research.

Sphinganine from milk
Johnson Lab/Provided
A new technique allows researchers to track specific nutrients as they are taken up by gut microbes in a mouse's digestive tract. The image shows certain microbes (red) taking in a nutrient common in human milk called sphinganine; blue microbes have not taken it in.

The paper describes an innovative technique developed at Cornell to track the fate of metabolites - nutrients formed in or necessary for metabolism - through a mouse's digestive tract and identify how they interact with specific gut microbes.

"We think the methods are expandable to many different microbiome systems," said senior author Elizabeth Johnson, assistant professor of nutritional sciences in the College of Agriculture and Life Sciences. She noted that researchers investigating effects of a high-fat vs. low-fat diet, or a keto diet, might use the technique to track metabolites.

The methodology could reveal how specific metabolites promote specific bacteria. This could allow nutritionists to prescribe that patients eat foods containing specific metabolites to intentionally change the composition of their microbiomes, Johnson said.

Human milk and many other foods contain a class of lipid metabolites called sphingolipids. Previous research suggested that these metabolites help shape an infant's microbiome, but it was not known if they actually interact with the microbiome.

The study identified two types of gut microbes, Bacteroides and Bifidobacterium, that use sphingolipids for their own metabolism.

While very little is known about the specific roles of gut microbes in human health, Bacteroides have been implicated in both beneficial and not-so-beneficial effects, depending on context. They are generally associated with microbiomes of healthy breastfed infants. Bifidobacterium, shown for the first time in this study to process dietary sphingolipids, are considered the quintessential beneficial bacteria, comprising up to 95% of breastfed infants microbiome.

They're also a highly popular over-the-counter probiotic.

"Our lab is very interested in how the diet interacts with the microbiome in order to really understand how you can best modulate it to have positive effects on health," Johnson said. "In this study, we were able to see that yes, these dietary lipids that are a big part of [breastfed] infants diets, are interacting quite robustly with the gut microbiome."

Sphingolipids originate from three main sources: diet; bacteria that can produce them; and most host tissues.

Johnson, along with first author Min-Ting Lee, a doctoral student, and Henry Le, a postdoctoral researcher, both in Johnson's lab, created a technique to specifically track dietary sphingolipids as they passed through the mouse gut.

"We custom synthesized the sphingolipid we added to the diet," Johnson said. "It is almost identical to ones derived from breast milk but with a small chemical tag so we could trace the location of the sphingolipid once it was ingested by the mice."

Lee then used a fluorescent label that attached to cells or microbes that absorbed the tagged lipid, such that any bacteria that had taken up sphingolipids lit up red. Microbes from the mice's microbiomes were then isolated and analyzed. Populations with red microbes were separated from the others, and these were then genetically sequenced to identify the species of bacteria.

With further investigation, Le was able to identify the metabolites that Bacteroides and Bifidobacterium produce when exposed to dietary sphingolipids. Further investigations are underway to determine whether these microbially-produced metabolites are beneficial for infant health.

NASA-NOAA's Suomi NPP satellite provided a nighttime view of the Atlantic Ocean hurricane season's latest tropical cyclone off the coast of North Carolina. Ocean swells from the depression are affecting coastal North Carolina today, Sept. 1.

Tropical Depression 15 formed by 5 p.m. EDT off the coast of North Carolina and showed organized convection (rising air that forms the thunderstorms that make up a tropical cyclone). The storm has been battling vertical wind shear since its formation, which has kept it from intensifying into a tropical storm.

NASA's Night-Time View

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a nighttime image of 15 during the early morning hours of Sept 1 when it flew over the northwestern Atlantic Ocean. Infrared data showed the most powerful thunderstorms east of center where cloud top temperatures were as cold as or colder than minus 70 degrees Fahrenheit. Deep convection remains displaced to the east and southeast of the depression's low-level center due to increasing west-northwesterly wind shear.

The image was created using the NASA Worldview application at NASA's Goddard Space Flight Center, Greenbelt, Md.

TD15's Status

At 11 a.m. EDT (1500 UTC), NOAA's National Hurricane Center (NHC) reported the center of Tropical Depression 15 (TD 15) was located near latitude 34.7 degrees north and longitude 73.1 degrees west. TD 15 is centered about 140 miles (225 km) east-southeast of Cape Hatteras, North Carolina. The depression is moving toward the east-northeast near 14 mph (22 kph). This general motion is forecast today, followed by a turn toward the east by Thursday. On the forecast track, the center of the depression will continue to move away from the North Carolina coast today.

Maximum sustained winds remain near 35 mph (55 kph) with higher gusts. The depression could become a tropical storm later today or tonight. Gradual weakening is anticipated by late Wednesday. The system is forecast to become a remnant low on Thursday.

TD15's Effects Along the U.S. Coast

Although the depression is off the coast of North Carolina it is generating ocean swells that are affecting the U.S. coast. NHC said, "Swells generated by the depression will continue to affect portions of the Outer Banks of North Carolina through this evening, causing life-threatening surf and rip current conditions." There are no other watches or warnings in effect and the storm is forecast to move away from the coast.

About NASA's EOSDIS Worldview

NASA's Earth Observing System Data and Information System (EOSDIS) Worldview application provides the capability to interactively browse over 700 global, full-resolution satellite imagery layers and then download the underlying data. Many of the available imagery layers are updated within three hours of observation, essentially showing the entire Earth as it looks "right now."

NASA Researches Earth from Space

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America's leadership in space and scientific exploration.

Online crowdfunding is a multibillion dollar industry, but crafting a compelling pitch that stands out among thousands of projects and lands investors is challenging. This is especially true for small-scale independent restaurant concepts where, due to intense industry competition, risk is high. Kickstarter's food category can have about 30,000 active pitches at any given time, but only about 25% achieve their fundraising goals. In other words, three out of four come up short and fail.

In text analysis of 500 crowdfunding restaurant campaigns on Kickstarter, one of the most popular crowdfunding platforms, researchers at the Conrad N. Hilton College of Hotel and Restaurant Management at the University of Houston identified linguistic styles that could tip the scales for restaurateurs seeking financial backing online.

Project descriptions that are concrete in style and deliver stories with fewer usage of first person pronouns, such as "I" and "my," are more likely to succeed, according to the findings published in the International Journal of Contemporary Hospitality Management.

Lead study author Yoon Koh, associate professor at UH's Hilton College, said concrete words allow faster processing and effectively reduces uncertainty about and strengthens confidence in anticipated business performance. According to previous research in the field of linguistics, three cues to concreteness are use of articles ("a," "an" and "the"), prepositions ("at," "since" and "for") and quantifiers ("few," "many" and "most").

"Concrete language uses specifics so investors can actually picture the idea and what this restaurant is all about. It brings more concrete images to their minds," said Koh. "For example, when discussing the location of the proposed restaurant don't say 'it's in this area.' Instead, be specific and give the exact street. Or don't say you 'have a lot of experience.' Say you've 'operated restaurants since 1995.'"

An interactive pitch that poses questions to potential investors such as: "Do you want to be part of a great new restaurant concept?" had a negative impact, according to Koh. She notes there are other ways to be interactive such as posting more updates to your project pitch (e.g. "We have reached 50% of our goal!"). Successful projects approximately tripled the number of updates of unsuccessful projects.

"The restaurant industry is ultra-competitive so getting any kind of advantage through data is big. You can know everything about your concept and industry, but if you can't use the right language to communicate it, then you may not succeed," said Koh. "A simple tweak in language style could mean the difference between achieving success, or joining the thousands of restaurant concepts that never get a chance."

A new Tel Aviv University study examined the brain's reactions in conditions of uncertainty and stressful conflict in an environment of risks and opportunities. The researchers identified the areas of the brain responsible for the delicate balance between desiring gain and avoiding loss along the way.

The study was led by TAU researchers Prof. Talma Hendler, Prof. Itzhak Fried, Dr. Tomer Gazit, and Dr. Tal Gonen from the Sackler Faculty of Medicine, the School of Psychological Sciences, and the Sagol School of Neuroscience, along with researchers from the Tel Aviv Sourasky Medical Center (Ichilov) and the University of California, Los Angeles School of Medicine. The study was published on June 24, 2020, in the journal Nature Communications.

Prof. Hendler explains that in order to detect reactions in the depths of the brain, the study was performed among a unique population of epilepsy patients who had electrodes inserted into their brains for testing prior to surgery to remove the area of the brain causing epileptic seizures. Patients were asked to play a computer game that included risks and opportunities, and the electrodes allowed the researchers to record, with a high level of accuracy, neural activity in different areas of the brain associated with decision-making, emotion, and memory.

Throughout the game, the researchers recorded the electrical activity in the subjects' nerve cells immediately after they won or lost money. The subjects were asked to try to collect coins while taking the risk of losing money from their pool. It was found that the neurons in the area of the inner prefrontal cortex responded much more to loss (punishment) than to the gaining (reward) of coins.

Moreover, the researchers found that the avoidance of risk-taking in the players' next move was affected mainly by post-loss activity in the area of the hippocampus, which is associated with learning and memory, but also with anxiety. This finding demonstrates the close relationship between memory processes and decision-making when risk is present (stressful situations). That is, the loss is encoded in the hippocampus (the region of the brain associated with memory), and the participant operating in a high-risk stressful situation preferred to be cautious and avoid winning the coins (forfeiting the gain).

The experience of winning, however, was not encoded in the memory in a way that influenced the choice of future behavior in conditions of uncertainty. An interesting point is that this phenomenon was found only when the subject was influencing the result of the game, and only in the presence of a high risk in the next move, which indicates a possible connection to anxiety.

"Throughout life, we learn to balance the fear of risking loss with the pursuit of profit, and we learn what is a reasonable risk to take in relation to the gain based on previous experiences," Prof. Hendler says. "The balance between these two tendencies is a personality trait but is also affected by stress, like the current pandemic. A disorder in this trait increases sensitivity to stress and can cause non-adaptive behavior such as a high propensity for risk-taking or excessive avoidance.

"Our research shows for the first time how the human brain is affected by the experience of failure or loss when it is our responsibility, and how this inclination produces avoidance behavior under particularly stressful uncertainty," Prof. Hendler concludes. "An understanding of the neural mechanism involved may guide future neuropsychiatric therapies for disorders featuring excessive avoidance, such as depression, anxiety, and PTSD, or disorders associated with excessive risk-taking, such as addiction and mania."

Below please find a summary and link(s) of new coronavirus-related content published today in Annals of Internal Medicine. The summary below is not intended to substitute for the full article as a source of information. A collection of coronavirus-related content is free to the public at http://go.annals.org/coronavirus.

Fecal aerosol from pluming system may be to blame for COVID-19 spread in China high-rise

The presence of SARS-CoV-2 in fecal material has raised the possibility of viral transmission via a fecal-oral route. Researchers from the University of Hong Kong investigated whether SARS-CoV-2 transmission via fecal aerosols in the drainage pipe system may have been the cause of COVID-19 infection in a cluster of three families living in a high-rise apartment building in Guangzhou, China. The team studied throat swabs from infected patients, other building residents, and building staff; 237 surface and air samples from 11 of the 83 flats in the building, public areas, and building drainage systems; and tracer gas released into bathrooms as a surrogate for virus-laden aerosols in the drainage system. Based this circumstantial evidence, the researchers concluded that the outbreak within the block may have been caused by fecal aerosol transmission that occurred after toilet flushing by infected patients. The researchers suggest ways to prevent such transmission, such as adequate hygiene in sanitary drainage, and bathroom ventilation and hygiene. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-0928.

The author of an accompanying editorial from Heriot-Watt University, Edinburgh, United Kingdom, discusses the researchers' findings and why wastewater systems, particularly those in high-rise buildings, deserve closer investigation as a reservoir for harmful pathogens. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-6134.

Media contacts: A PDF for this article is not yet available. Please click the link to read full text. The lead authors can each be reached directly: Yuguo Li, PhD (liyg@hku.hk); Jianfeng He, BSc (hjf@vip.sina.com); Nanshan Zhong, PhD (nanshan@vip.163.com). The editorialist, Michael Gormley, PhD, CEng, can be reached at m.gormley@hw.ac.uk.

An empirical study published in the Journal of Political Economy finds that VAT cuts are less likely to be passed on to consumer prices than VAT hikes. Following a temporary VAT cut, prices can even be higher than on onset.

A number of countries are adopting temporary reductions to VAT rates as a means to support businesses hit by the corona lockdown. The expectation is that businesses will pass the reductions on to consumer prices and thereby boost consumer spending. However, according to the study, most businesses use VAT cuts to improve their finances instead of cutting prices.

A part of the study is formed by the analysis of VAT changes within the hairdressing industry in Finland. In 2007, the VAT rate for hairdressing services was reduced by 14 percentage points. After five years, in 2012, the standard rate was reintroduced increasing the VAT on hairdressing services by the same 14 percentage points.

According to the study, 60 % of prices did not respond to the VAT cut. However, they did respond to the reinstatement of the standard VAT rate: Almost all companies increased their prices by 80 to 120 % of the VAT rate increase.

- The VAT cut did slightly reduce prices, but returning to the standard rate increased prices by twice as much. Indeed, when the VAT reduction ended, the prices for hairdressing services were higher than they had been before the VAT cut, says research director Tuomas Kosonen from the Labour Institute of Economic Research.

The increase in the firms profits and markups following the VAT cut was twice as large as the reduction in profits and markups after the VAT hike.

- In particular, firms with low markups tend to respond asymmetrically to changes in VAT rates. They do not reduce their prices in response to VAT cuts, but they increase their prices considerably if the VAT rate is raised, states research professor Jarkko Harju from the VATT Institute for Economic Research.

EU-wide study: Prices react asymmetrically to VAT changes

The results do not only apply to hairdressing services in Finland. Harju and Kosonen teamed up with Youssef Benzarti (University of California Santa Barbara and NBER) and Dorian Carloni (Congressional Budget Office) to expand their research to encompass all VAT changes that took place in EU countries between 1996 and 2015.

They study VAT rate changes for over 2800 different commodities and find that prices tend to rise 3 to 4 times more after a VAT hike and they are reduced following VAT cut.

- Typically assessments of the the demand-side effects of VAT changes assume that the price effects of VAT cuts and hikes are symmetrical and that the tax changes are fully passed on to consumer prices. However, our empirical study clearly shows that such assessments overestimate the impact of VAT cuts on consumer spending, says Jarkko Harju.

- In Finland and other Nordic countries, good quality data from tax officials enables the precise study of the behavioural impacts of taxation. This study is in line with our other studies, which also find that the impact of consumption taxes on the consumption of goods and services is in effect rather modest, Tuomas Kosonen concludes.

World maritime trade grows each year, aided by canal waterways that connect oceans and reduce shipping time, energy consumption and carbon emissions. Following recent expansions of the Panama and Suez canals, non-native fish species are invading new habitats according to a new report in Nature Ecology and Evolution by researchers at the Smithsonian Tropical Research Institute (STRI) in Panama and the Leibnitz Center for Tropical Marine Research (ZMT) in Germany.

"We're seeing a shift from predominantly freshwater fishes to marine fishes in the Panama Canal (Lake Gatun) in a short period of time," said Mark Torchin, STRI marine ecologist. "The concern is that if fish invasions continue there is a good chance of some of those fishes moving into the other ocean, with unknown environmental consequences."

Larger locks to allow transit of NeoPanamax vessels (NeoPanamax refers to ships too big to pass through the original 1914 locks) through the Panama Canal were finished in 2016. Expansion of the Suez Canal to include a new, 35-kilometer channel concluded in 2015.

"During the planning phases of both projects, researchers warned about the risks of expanding these two canals," said Gustavo Castellanos-Galindo, postdoctoral fellow at STRI and guest scientist at ZMT. "This report documents those changes in real time."

Only four years after the Panama Canal expansion, long-term monitoring recorded the presence of 11 new marine fish species in Lake Gatun, which has served as a freshwater barrier to movement of marine fauna between Pacific and Atlantic Oceans since the canal opened in 1914. This takes the total number of marine fish species known from in the lake from 18 to 29. Marine fishes such as jacks, snooks, mojarras and ladyfish have entirely replaced freshwater fishes in some parts of the lake.

Salinity in the lake increased, although the cause has not yet been determined. Possibilities include increased ship traffic and lock usage and the new locks' design, which incorporates recirculation of some lockage water.

"These marine fish invasions are an early warning sign of what could happen if no corrective measures are taken," Castellanos-Galindo said. "Along both coasts of Panama there are hundreds of fish species that could tolerate the conditions of an even slightly brackish canal. We don't know what the ecological and socioeconomic consequences of these fishes crossing the canal to either the Pacific or the Atlantic would be."

"We can document the Panama Canal invasions because we have good, standardized and quantitative pre-expansion data," said D. Ross Robertson, STRI ichthyologist. "We need to get back out there to collect more data to find out exactly what is going on and to provide the science that will help policy makers mitigate the potential impact. This is a really good example of how the pandemic has interrupted field work with important implications for environmental decision making."

Whereas the barrier to fish crossing from ocean to ocean in Panama is a freshwater lake, in the Suez waterway, the Bitter Lakes were originally saltier than the Mediterranean and Red Sea, which also limited species movement. Nonetheless, throughout the history of the Suez Canal, more than 400 non-native animal species, including more than 100 species of marine fishes from the Red Sea, have entered the Mediterranean. With canal expansion, increased water flow diluted the lakes and eight new fish species entered the Mediterranean during the past five years.

Because fees for shipping through the canals account for roughly 10% of the gross domestic product in Panama and in Egypt, there is an economic incentive to continue to increase shipping traffic through the canals. The authors suggest creative, science-based solutions to limit environmental and socioeconomic damage. They propose that the UN Decade of Ocean Science for Sustainable Development (2021-2030) may provide the ideal opportunity for ensuring that the canals are included in international maritime policy to limit the environmental and economic impacts of invasive species. In addition, because policy changes can take a long time to implement, they also suggest that the shipping industry could proactively address this issue.

The UN agency responsible for sustainable shipping, the International Maritime Organization, has implemented guidelines and obligations to reduce the spread of non-native species through ballast water--but they do not apply specifically to the canals.

In the case of the Suez Canal, it may be possible to use the hypersaline effluent from desalinization plants to make the Bitter Lakes saltier again, with the caveat that this alternative should be studied carefully before implementing. In both cases, sophisticated monitoring tools--using DNA in water samples to generate lists of the species detected and using sound to detect invaders, may help to catch invaders early before they establish large populations. Technology may also be put to work to directly address invasion by means of acoustic and/or electric barriers to deter invaders.

The authors hope that all of the stakeholders will recognize the importance of having the best scientific data in hand as they design new policy and mitigation measures.

Genetic analysis of sequences from more than 27,000 individuals infected with the coronavirus that causes COVID-19 reveals that the virus has mutated minimally since December 2019, suggesting one vaccine would be sufficient to combat global infections.

The study was conducted by a team of scientists from the Walter Reed Army Institute of Research led by Morgane Rolland, chief of viral genetics and systems serology for the WRAIR Military HIV Research Program and Dr. Kayvon Modjarrad, director of the institute's Emerging Infectious Diseases Program. A manuscript detailing the findings was published in Proceedings of the National Academy of Sciences.

To characterize SARS-CoV-2 coronavirus diversification since the beginning of the pandemic they aligned 18,514 independent virus genome sequences sampled from individuals in 84 countries and scanned them for variations. Analyses reveal low estimates of genetic differentiation following the initial outbreak, and indicate that, so far, the SARS-CoV-2 genome has evolved through a mostly random process rather than through adaptation to the human hosts it encounters.

"Like other reports, we noticed that the D614G mutation in the Spike has rapidly increased in frequency since the beginning of the epidemic, but we could not link this mutation to specific adaptive forces," said Rolland. "When viruses replicate and spread in the population, we expect to see some mutations and some can become fixed very rapidly in an epidemic just by random chance." Rolland noted that linking genotypes to phenotypes is complicated and more research is needed to fully understand the functional consequences of the D614G mutation in SARS-CoV-2.

Given the low level of genetic variation, a promising vaccine candidate would likely be equally efficacious against all currently circulating strains of the COVID-19 coronavirus.

"Viral diversity has challenged vaccine development efforts for other viruses such as HIV, influenza and dengue, but global samples show SARS-CoV-2 to be less diverse than these viruses," said Rolland. "We can therefore be cautiously optimistic that viral diversity should not be an obstacle for the development of a broadly protective vaccine against COVID-19 infection."

Modjarrad co-leads the institute's COVID-19 response efforts, including the development of a vaccine against COVID-19. WRAIR's leading vaccine candidate is built on a Spike Ferritin Nanoparticle platform and is expected to enter human testing before 2021. The vaccine is paired with a proprietary adjuvant that was also developed at WRAIR, the Army Liposome Formulation, to further boost the immune response.

"Scientists are working hard to accelerate the development of a COVID-19 vaccine that is safe and effective for the entire world, now and in the years to come. These data are critical to informing the field's collective efforts in getting a vaccine that is rapidly scalable and universally applicable to all populations," said Modjarrad.

He added, "Based upon WRAIR's long experience developing vaccines for other viruses and recent work on coronaviruses, we have been able to move quickly to accelerate research efforts to combat this pandemic that has threatened global health and military readiness." WRAIR was established 127 years ago to combat these types of health threats and has played a role in the development of nearly half of the vaccines in public use today.

Rolland, whose research usually focuses on HIV viral genetics, has shifted her attention to COVID-19 during the current global health emergency. "It's critical that people in various fields come together as we focus on learning everything we can about this virus," she said. "Teamwork will be vitally important to stem the tide of this pandemic." Rolland is employed by the Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., and has conducted research at WRAIR since 2010.

GAINESVILLE, Fla. --- You might think the buffest frogs would be high jumpers, but if you want shredded pecs, you should train like a burrowing frog. Though famously round, these diggers are the unsung bodybuilders of the frog world. We bring you tips from frog expert Rachel Keeffe, a doctoral student at the University of Florida, and physical therapist Penny Goldberg to help you get the burrowing body of your dreams.

But first, a caveat: According to Keeffe, no workout regimen can help you train your way into a highly specialized frog physique honed by 200 million years of evolution. To better understand burrowing frog anatomy, Keeffe and her adviser David Blackburn, Florida Museum of Natural History curator of herpetology, analyzed CT scans from all 54 frog families to show these frogs boast a robust and quirky skeleton that is more variable than previously thought.

"People think about frogs as being clean and smooth and slimy, or the classic 'green frog on a lily pad,' but a lot of them are dirty - they like to scoot around and be in the dirt," Keeffe said. "Burrowing frogs are really diverse and can do a lot of cool things. And when you look at the skeletons of known burrowers, they're very different from what you would call a 'normal frog.'"

Burrowing frogs are found all over the world from deserts to swamps, but their underground lifestyle makes them difficult to study, Keeffe said. Most tunnel hind end-first with their back legs. But a few species are forward burrowers, using pointed snouts and powerful forelimbs bolstered by strong pectoral muscles to scrabble into the earth.

Keeffe's sample of 89 frog species revealed radical differences in burrowing bone structure, from clavicles the size of eyelashes to other bones that are unusually thick.

"They're so diverse that it's challenging to think about even comparing them. It's almost a black hole of work that we can do with forward burrowers because we tend to focus on the legs," she said.

Some burrow to seek refuge, whether from arid temperatures or predators, and underground habitats can be hunting grounds or secluded hiding places. Other burrowing frogs can spend months at a time as deep as 3 feet belowground, surviving on a high-protein diet of termites and ants. The takeaway: If you want to compete for resources with the pros, don't be afraid to put in the work.

Get the burly burrowing body

To train like a burrowing frog, Goldberg, assistant director of ReQuest Physical Therapy in Gainesville, recommended dedicating time to strengthening your upper back.

"In humans, the most important muscle group to focus on if you were to train like one of these frogs would be the scapular stabilizers," she said. "These include 17 muscles, such as the lats and rotator cuff, with attachments all the way down to the pelvis that allow the upper back to generate power. To burrow like a forward burrower, you need to strengthen this entire region."

One strengthening move Goldberg recommended is the "Prone W." Lie facedown with elbows bent and palms on the floor. Squeeze your shoulder blades down and toward your spine as you lift your arms to the ceiling for a couple seconds at a time.

Like any elite athlete, burrowing frogs also maintain an optimal form. They're often orb-shaped to improve their ability to hold water.

"Personally, if I were a sphere, I think it would be hard for me to dig, but it doesn't seem to affect these frogs at all," Keeffe said. "However, frogs with stumpy legs are definitely worse at jumping, and they tend to stagger when they walk."

For these frogs, time away from the tunnels might be spent swimming instead, Keeffe said. To compete here, Goldberg recommends the breaststroke, adding that her top training tips for getting the upper back and pecs of a forward burrower would include pullups and pushups to develop the shoulder blade area.

"In my world, we would use resistance bands and pushing or pulling motions to train this area," Goldberg said. "Anything focusing predominantly on building strength in the upper back region."

If resistance bands are part of your workout routine, try grasping one with both hands and extending your arms while keeping your elbows straight. For best results, Goldberg recommended starting with three sets of 10.

Burrowing frogs might also hold key answers to gaps in scientists' understanding of amphibian evolution at large. Keeffe's analysis also found that forward-burrowing behavior evolved independently at least eight times in about one-fifth of frog families, and the trait's persistence in the frog family tree suggests it's a beneficial adaptation. Keeffe also found that forward burrowers tended to have a highly contoured humerus, the bone that connects the shoulder to the elbow in humans.

Understanding how bone shape relates to musculature can help scientists identify which frogs, both modern and extinct, are forward burrowers, a helpful tool given their covert behavior.

"Even though it can be frustrating, I like them because they're secretive," Keeffe said. "But the whole thing underlying this study is that frogs can do a lot of cool things - they don't just jump and they're not just green."

CT scans were generated from the National Science Foundation-funded oVert project.

Studies show that athletes and musicians achieve peak performance not only by constant practice but also by setting specific goals, engaging with strong mentors and cultivating the attributes of perseverance, stoicism and grit. Could incorporating these principles into the training of surgeons improve their residency experience and make them better doctors?

Philip Louie, MD, who recently completed a spine surgery fellowship at Hospital for Special Surgery (HSS), has given the subject a lot of thought. "Peak performance is the ability to achieve optimal outcomes or performance of a given task in a consistent manner. Although commonly studied in athletes and musicians and promoted in other careers as well, peak performance is rarely considered for those undergoing the rigors of surgical training," he said.

A classically trained musician and former varsity athlete himself, Dr. Louie thought about how he could apply his preparation in these areas to surgical residency training and help others achieve peak performance. Long interested in the kind of growth mindset that drives long-term success, he majored in business before attending medical school to gain new insights and learn to "think outside the box," he said.

Dr. Louie and colleagues at HSS set out to review the current literature on residency training and to discuss the value of assessment tools and critical performance measures. In an article published in the Journal of the American Academy of Orthopaedic Surgeons, the HSS physicians offer practical advice for both educators and trainees on reaching peak performance.

"Residency is a crucial period of training where foundations for future success are established by habit and daily practice," said Michael McCarthy, MD, a former spine surgery fellow at HSS and co-author. Dr. McCarthy, a former college football player and history major, cited the intensity of Division I athletics and the diversity of thought and opinion in his studies as the foundation and impetus to explore achieving peak performance in training. "We believe the same tools that enable those in other fields to be at their best could equip surgical trainees with the tools necessary to achieve peak performance. It's crucial for physicians seeking to perform at the top of their game and will ultimately benefit patients."

The HSS physicians say peak performance is essential in an evolving health care landscape that demands optimal clinical outcomes and value-based medicine. The COVID-19 pandemic is also placing unprecedented demands on physicians. Coronavirus cases surged while Drs. Louie and McCarthy were in the middle of their spine surgery fellowship. The attributes they discussed in their article of perseverance, grit and stoicism were essential when, almost overnight, HSS went from an orthopedic specialty hospital to a "surge" center treating coronavirus patients to take the load off overwhelmed neighboring hospitals.

"During that stressful time, when New York City was the epicenter of the pandemic and we cared for COVID patients in the ICU, the important thing was to take a step back and remember why we decided to enter medicine," Dr. Louie notes. "We had been given the gift of opportunity, and it was our duty to persevere and make the most of it and play our role in guiding our communities through the crisis. What we gained from collaborating with other healthcare professionals and caring for patients in their time of greatest need will last far beyond the pandemic."

When the crisis was under control in New York City, HSS transitioned back to a dedicated musculoskeletal center, resuming elective surgeries in the beginning of June.

In their article, Drs. Louie and McCarthy outline several key areas and recommendations to achieve peak performance, including growing self-awareness through mindful activities. "We realize that some of these concepts are off the beaten path for orthopedic trainees, but they're important nevertheless," said Dr. McCarthy. "When you're used to focusing on evidence-based medicine, these can seem like nebulous concepts, a skill set difficult to grasp for detailed-oriented surgeons."

They break down their recommendations on reaching peak performance into five key areas that encompass both physical and mental skills:

1 - Translating Practices from Peak Performers in Other Fields

Refine physical skills through improving mental engagement during a task. Practice focusing solely on the task at hand.

Develop a program for deliberate practice in which you can undergo critical assessments to allow for graduated improvement.

Grow self-awareness through mindfulness activities to promote "flow" states. The term "flow" is best described as a state of full engagement, control, concentration and action awareness occurring during an activity perceived as highly rewarding and characterized by clear goals.

Create and consistently review step-by-step notes on specific techniques to develop proficiency that can be translated directly to intraoperative opportunities.

2 - Goal Setting and Accountability

Align goals with values, create a plan and visualize the goals.

Identify an accountability partner or system.

Anticipate obstacles and possible solutions.

Ensure work-life balance.

Reward goal accomplishment.

3 - Developing Technical Skills

Seek opportunities outside the OR for skill acquisition. Evaluate how other departments in the hospital may be training their residents.

Encourage the program director to consider new technologies, such as bioskills simulations and virtual reality training.

Upon seeking feedback on surgical techniques and proficiency, identify activities that can improve areas requiring additional practice.

4 - Perseverance and Grit

Believe in constant change and grow.

Understand that frustrations are part of the process.

Focus on productivity.

Look for ways to make work more meaningful.

Practice deliberately.

Consider the principles based on Stoicism during long periods of difficulty or moments of crisis.

5 - Mentorship

Monitor, track and measure the results of the mentorship relationship.

Define the strategic purpose of the mentorship.

Identify a strong match based on the skills of the mentor and the needs of the mentee.

Both Drs. Louie and McCarthy underscore the importance of mentorship and say they appreciate the "amazing" mentors they had at HSS: spine surgeons Todd Albert, MD, and Han Jo Kim, MD. But many residents and fellows at other hospitals are not as fortunate, Dr. Louie notes. "A lot of mentors don't put time into the relationship. They only meet with the trainee twice a year," he says. "I think mentorship needs to be much more formalized. You need to ensure a good match and set formal strategic goals on both sides of the mentorship. There needs to be accountability and checkpoints over time as to how the relationship is going and what can be done to improve it."

Drs. Louie and McCarthy recently completed their fellowship training, but they plan to continue to collaborate with doctors at HSS to establish an initial curriculum based on the principles and strategies they outline in their paper. They believe educators should aim to equip surgical residents with the tools necessary to achieve peak performance during training, so they can apply what they learn throughout their careers.

How do people coordinate their actions with the sounds they hear? This basic ability, which allows people to cross the street safely while hearing oncoming traffic, dance to new music or perform team events such as rowing, has puzzled cognitive neuroscientists for years. A new study led by researchers at McGill University is shining a light on how auditory perception and motor processes work together.

Keeping the beat - it takes more than just moving or listening well

In a recent paper in the Journal of Cognitive Neuroscience, the researchers, led by Caroline Palmer, a professor in McGill's Department of Psychology, were able to identify neural markers of musicians' beat perceptions. Surprisingly, these markers did not correspond to the musician's ability to either hear or produce a beat - only to their ability to synchronize with it.

"The authors, as performing musicians, are familiar with musical situations in which one performer is not correctly aligned in time with fellow performers - so we were interested in exploring how musician's brains respond to rhythms. It could be that some people are better musicians because they listen differently or it could be that they move their bodies differently," explains Palmer, the Canada Research Chair in Cognitive Neuroscience of Performance, and the senior author on the paper.

"We found that the answer was a match between the pulsing or oscillations in the brain rhythms and the pulsing of the musical rhythm - it's not just listening or movement. It's a linking of the brain rhythm to the auditory rhythm."

Super-synchronizers - an exception or a learnable skill?

The researchers used electroencephalography (EEGs involve placing electrodes on the scalp to detect electrical activity in the brain) to measure brain activity as participants in the experiment, all of them experienced musicians, synchronized their tapping with a range of musical rhythms they were hearing. By doing so they were able to identify neural markers of musicians' beat perceptions that corresponded to their ability to synchronize well.

"We were surprised that even highly trained musicians sometimes showed reduced ability to synchronize with complex rhythms, and that this was reflected in their EEGs," said co-first authors Brian Mathias and Anna Zamm, both PhD students in the Palmer lab. "Most musicians are good synchronizers; nonetheless, this signal was sensitive enough to distinguish the "good" from the "better" or "super-synchronizers", as we sometimes call them."

It's not clear whether anyone can become a super-synchronizer, but according to Palmer, the lead researcher, it may be possible to improve ones ability to synchronize.

"The range of musicians we sampled suggests that the answer would be yes. And the fact that only 2-3 % of the population are 'beat deaf' is also encouraging. Practice definitely improves your ability and improves the alignment of the brain rhythms with the musical rhythms. But whether everyone is going to be as good as a drummer is not clear."