The new tattoo: Drawing electronics on skin

MU engineers discover the possibility of using pencils to draw bioelectronics on human skin

UNIVERSITY OF MISSOURI-COLUMBIA

 

IMAGE: ONE DAY, PEOPLE COULD MONITOR THEIR OWN HEALTH CONDITIONS BY SIMPLY PICKING UP A PENCIL AND DRAWING A BIOELECTRONIC DEVICE ON THEIR SKIN. IN A NEW STUDY, UNIVERSITY OF MISSOURI... view more 

CREDIT: UNIVERSITY OF MISSOURI

One day, people could monitor their own health conditions by simply picking up a pencil and drawing a bioelectronic device on their skin. In a new study, University of Missouri engineers demonstrated that the simple combination of pencils and paper could be used to create devices that might be used to monitor personal health.

Their findings are published in the journal Proceedings of the National Academy of Sciences.

Zheng Yan, an assistant professor in the College of Engineering, said many existing commercial on-skin biomedical devices often contain two major components -- a biomedical tracking component and a surrounding flexible material, such as plastic, to provide a supportive structure for the component to maintain an on-skin connection with a person's body.

"The conventional approach for developing an on-skin biomedical electronic device is usually complex and often expensive to produce," he said. "In contrast, our approach is low-cost and very simple. We can make a similar device using widely available pencils and paper."

Since its invention, pencils -- made of lead including various levels of graphite, clay and wax -- have often been used for writing and drawing. In the study, the researchers discovered that pencils containing more than 90% graphite are able to conduct a high amount of energy created from the friction between paper and pencil caused by drawing or writing. Specifically, the researchers found pencils with 93% graphite were the best for creating a variety of on-skin bioelectronic devices drawn on commercial office copy paper. Yan said a biocompatible spray-on adhesive could also be applied to the paper to help it stick better to a person's skin.

The researchers said their discovery could have broad future applications in home-based, personalized health care, education and remote scientific research such as during the COVID-19 pandemic. Yan said the group's next step would be to further develop and test the use of the biomedical components, including electrophysiological, temperature and biochemical sensors.

"For example, if a person has a sleep issue, we could draw a biomedical device that could help monitor that person's sleep levels," he said. "Or in the classroom, a teacher could engage students by incorporating the creation of a wearable device using pencils and paper into a lesson plan. Furthermore, this low-cost, easily customizable approach could allow scientists to conduct research at home, such as during a pandemic."

An additional benefit to their approach, Yan said, is that paper can decompose in about a week, compared to many commercial devices that contain components that are not easily broken down.

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The study, "Pencil-paper on-skin electronics," was published in Proceedings of the National Academy of Sciences. Other authors on the study are Yadong Xu, Ganggang Zhao, Qihui Fei, Zhe Zhang, Zanyu Chen, Yangyang Chen, Yun Ling, Shinghua Ding and Guoliang Huang at MU; Liang Zhu and Pai-Yen Chen at the University of Illinois-Chicago; Fufei An and Qing Cao at the University of Illinois Urbana-Champaign; and Peijun Guo at Yale University.

Funding was provided by a University of Missouri start-up fund, and grants from the National Science Foundation, the Air Force Office of Scientific Research and the National Institutes of Health. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies.

Green is more than skin-deep for hundreds of frog species

Biochemical workaround makes pigment that tunes light to the exact shade of a green leaf

DUKE UNIVERSITY

IMAGE: THE GLASS FROG ESPADARANA HAS TRANSLUCENT SKIN AND GREEN INSIDES, THANKS TO AN EVOLUTIONARY ADAPTATION THAT TURNED A TOXIC BYPRODUCT OF BLOOD BREAKDOWN INTO A LOVELY GREEN PIGMENT. EVEN ITS... view more 

CREDIT: SANTIAGO R. RON

DURHAM, N.C. -- Frogs and toads are green for a very good reason - it makes them harder to see in their leafy environments. Good camouflage allows them to eat and not be eaten. But not all frogs have arrived at this life-saving greenness in the same way.

Most of these animals rely on color-controlling structures in their skin called chromatophores that use crystals to bend light to specific colors and make them appear green. But there are hundreds of species of frogs and toads that have nearly translucent skin and very few chromatophores.

Their greenness, which can be found deep in their lymphatic fluid, soft tissues and even bones, comes from a clever biochemical workaround that combines a normally virus-fighting type of protein with a toxic byproduct of blood breakdown.

The finding, by post-doctoral researcher Carlos Taboada at Duke University, solves a few longstanding mysteries about these frogs and shows how the necessity of survival can be very inventive indeed. It appears the week of July 13 in the Proceedings of the National Academy of Sciences.

Scientists have long grappled with the fact that many of these frogs contain very high levels of bile pigment called biliverdin that is a byproduct of breaking apart old red blood cells. This pigment is normally considered a toxin to be filtered out in the liver and excreted as quickly as possible. But these frogs are found to carry four times as much biliverdin as even the sickest human with liver disease, and 200 times as much as their chromatophore-equipped frog cousins.

To understand the biochemistry better, the researchers focused on one species, Boana punctata, the polka-dot treefrog of South America. From it, they isolated a protein they're calling BBS (biliverdin-binding serpin), which is part of a superfamily of protease inhibitors, the proteins that normally step in the way of viral replication and detoxify enzymes.

When you see something green, its color really should be called 'everything but green,' because it is soaking up all the colors of incoming light except for green. The color we see is the frequency of light it does not absorb that bounces back to our eyes.

Biliverdin by itself would appear to be somewhat greenish, as sometimes seen in an old bruise, but the researchers found that a bound serpin, BBS, stretches out biliverdin's helical shape to fine-tune its light absorbance, making it more cyan, a blue-green. Cyan, added to some other yellow pigments scattered in the skin, bounces back just the right shade of green. It also makes biliverdin less toxic as well, apparently.

"This new protein has the same spectroscopic properties or light absorption properties as some plant pigments," said Taboada, who began the work in Argentina, Ecuador and Brazil and completed it at Duke. "The light properties are very similar to what we see, for example, in some plant proteins called phytochromes. But here we have a completely different protein."

It's a clever adaptation of existing biochemistry that normally serves other functions in vertebrates. Taboada said this innovation has evolved more than 40 times across 11 different families, most of them treefrogs. The adaptation happened again and again in far-flung Madagascar, South America and Southeast Asia.

"So this is a convergence in evolution," Taboada said. "Being arboreal (living in trees), they developed a different way to make their coloration." Their through-and-through greenness ensures good camouflage on foliage, even in near-infrared light.

"This shows how natural selection can co-opt proteins for just about any purpose," said Sönke Johnsen, a professor of biology at Duke and coauthor on the paper. "Biliverdin is a bile pigment that would normally be excreted from the body because of its potential for harm, but here it is in spectacular concentrations precisely because it's also useful as a green pigment."

"In other words, Kermit has jaundice," Johnsen said.

Having earlier discovered that many species of frogs reflect fluorescent wavelengths - essentially glowing in the dark - Taboada is now working with engineers at Duke's Pratt School of Engineering to shine precisely tuned lasers at frogs to learn more about their coloration.

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"This paper is a tour de force reach between the worlds of molecular biology, biochemistry, and ecology," Johnsen said.

CITATION: "Multiple Origins of Green Coloration in Frogs Mediated by a Novel Biliverdin-Binding Serpin," Carlos Taboada, Andres E. Brunetti, Mariana L. Lyra, Robert R. Fitak, Ana Faigon, Santiago R. Ron, Maria G. Lagorio, Célio F. B. Haddad, Norberto P. Lopes, Sönke Johnsen, Julian Faivovich, Lucia B. Chemes, Sara E. Bari. Proceedings of the National Academy of Sciences, July 13, 2020. DOI: 10.1073/pnas.2006771117

POSTECH solves the durability issue of hydrogen cars

POHANG UNIVERSITY OF SCIENCE & TECHNOLOGY (POSTECH)

 

IMAGE: APPLYING THE MIT PHENOMENON OF W03 IN NORMAL OPERATION RESULTS IN AN ELECTRODE REACTION WHILE MAINTAING THE H-W03 (CONDUCTOR) STATE WITH THE INSERTION OF A PROTON (LEFT). IN CONTRAST, WHEN... view more 

CREDIT: YONG-TAE KIM (POSTECH)

When a bicycle gets wet in the rain, the frame and chain become corroded or rusty which shorten the life of the bike. Oil needs to be regularly applied to prevent this from happening. Battery cells are devices that create electrical energy through moving electrons by triggering oxidation and reduction reactions separately. But they also corrode when exposed to oxygen. Can these cells also be greased to prevent rusting?

A research team led by Professor Yong-Tae Kim and doctoral student Sang Moon Jung of Materials Science and Engineering at POSTECH used a catalyst (Pt/HxWO3) that combines platinum and hydrogen tungsten bronze to solve the corrosion in fuel cells that occur when hydrogen cars are shut down. The catalyst, recently introduced in Nature Catalysis - a sister journal of Nature - has been shown to promote hydrogen oxidation and selectively suppress oxygen reduction reactions (ORR).

As eco-friendly hydrogen cars become more common, the race for research and development for improving fuel cell performance - the heart of hydrogen cars - is getting fierce around the world. The performance of automotive fuel cells are severely low owing to their intermittent shut-downs compared to power-generating fuel cells that do not stop once started. This is because when ignition is turned off, the ORR occurs as air is temporarily introduced into the anode, and corrosion of the cathodic components accelerates as the potential of cathod surges instantaneously.

The research team focused on the Metal Insulator Transition (MIT) phenomenon, which can selectively change the conductivity of materials depending on the surrounding environment, to solve the problem of durability degradation in automotive fuel cells.

n particular, the research team focused on the tungsten oxide (WO3) that has traditionally been used as an electrical discoloration material since it greatly changes conductivity via the insertion and reduction of protons. Applying the MIT phenomenon of WO3 in normal operation results in an electrode reaction while maintaining the H-WO3 (conductor) state with the insertion of a proton. In contrast, when ignition is shut-down, mixed air is drawn in which increases the oxygen pressure and changes it into WO3 (subconductor) which stops the electrode reaction, thus solving the issue of cathodic corrosion.

The Pt/HxWO3 selective hydrogen oxidation reaction (HOR) catalysts imparted by the metal-insulator transition phenomenon showed more than twice the durability of conventional commercial Pt/C catalyst materials in shut-down conditions in the MEA evaluation of automotive fuel cells.

Professor Yong-Tae Kim who led the research commented, "This research has dramatically improved the durability of automotive fuel cells." He added, "It is anticipated that the commercialization of hydrogen cars may be further facilitated through these findings."

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This research was conducted with the support from the Future Materials Discovery Project and the hydrogen energy innovation technology development program of the Ministry of Science and ICT.

NOT TO BE CONFUSED WITH FLUORIDE

How much fluorine is too much fluorine?

AMERICAN SOCIETY OF AGRONOMY

IMAGE: DAIRY COWS GRAZING CLOVER/RYEGRASS PASTURE ON A MASSEY UNIVERSITY PRODUCTION FARM. view more 

CREDIT: JAMES HANLY

For most of us, our closest encounter with the element fluorine is likely to be our toothpaste or a municipal water supply with added fluoride.

But excess fluorine can be a problem. For example, high levels of fluorine in the soil can hurt plants. Fluorine in soils may also affect microbes and other organisms higher along the food chain.

A new study explored whether soil fluorine levels in New Zealand are high enough to hurt a specific microbe called Rhizobium.

Rhizobium bacteria live in root nodules of legume plants, like beans and lentils. These bacteria 'fix' atmospheric nitrogen, making the nutrients into a form the host plant can use.

Nitrogen fixation by Rhizobia means farmers need to use less nitrogen fertilizer. That can save significant costs.

If soil fluorine levels become high enough to hurt Rhizobia, it could impact the legume crops the bacteria help support.

In addition, pastures for grazing livestock often contain clover, another legume. High fluorine levels could harm Rhizobia living in clover root nodules. Ultimately, that could impact the livestock that eat the clover.

But there are a lot of unknowns about fluorine and its specific effects on microbes. "No one has investigated the potential impact of fluorine on Rhizobia," says Christopher Anderson, a researcher at Massey University in New Zealand.

In the study, Anderson and colleagues found that high levels of fluorine are toxic to Rhizobia and white clover.

In laboratory studies, fluorine levels above 100 mg per liter hampered Rhizobia growth. High fluorine concentrations also led to changes in the shape and metabolic activity of the bacteria.

These high fluorine levels also impacted white clover. At fluorine concentrations above 100 mg per liter, white clover seedlings did not survive.

Fortunately, there's some good news as well. The concentration of fluorine at which it is toxic is much greater than the concentration the researchers found in New Zealand soils.

"This means that there is no problem, right now, of fluorine levels in soil affecting Rhizobia in New Zealand's soils," says Anderson.

This finding gives confidence to agencies in New Zealand that are tasked with ensuring sustainable farming systems. "Without our research, they would still be in the dark," says Anderson.

Rhizobia - and one of the host plants, white clover - are key parts of the New Zealand way of animal husbandry.

"In New Zealand, we are fortunate that we can grow grass year-round," says Anderson. "Our livestock are kept on pasture all year."

Rhizobium bacteria associated with clover fixes nitrogen from the atmosphere. When clover plants die, they break down in the soil. The fixed nitrogen becomes available to other plants.

"So, we don't need to apply as much synthetic nitrogen fertilizers, such as urea, to our pastures with clover" says Anderson.

But farmers need to apply other fertilizers to New Zealand's pastures, including phosphorus fertilizers. That's where concerns about fluorine levels come in.

Fluorine is a fairly common element in Earth's crust. It is concentrated in some materials, like phosphate rocks. These rocks are the main ingredient in many fertilizers with phosphorus.

In areas where phosphorus fertilizers are applied year after year, fluorine can accumulate in soils over time. This accumulated fluorine can become a soil contaminant.

"But in some cases, biological systems are very tolerant of contaminants," says Anderson.

Anderson aims to determine fluorine levels at which it is toxic to animals. "In particular we would like to look at earthworms," says Anderson. "Earthworms are very useful ecological indicators."

Researchers also want to look at grazing animals, which can eat a considerable amount of soil. When animals ingest too much fluorine, they can develop fluorosis. That can cause bone, teeth, and kidney problems.

"We have to make sure the science is looking after all aspects of the pastoral system - soil, microorganisms, plants, and animals," says Anderson.

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Read more about this research in Journal of Environmental Quality. This work is supported by The Fertiliser Association of New Zealand.

KIST develops "dielectrophoretic tweezer" technology for toxic nanoparticles

Technology developments for 'nanogap electrodes' to purify various ultra-fine floating particles in the air and water. Single particle? Scalable massive methodology control makes application in the environmental and medical sciences possible.

NATIONAL RESEARCH COUNCIL OF SCIENCE & TECHNOLOGY

 

IMAGE: MODEL DIAGRAM OF THE NANOGAP ELECTRODES ALLOWING THE DIELECTROPHORETIC TWEEZER TECHNOLOGY. view more 

CREDIT: KOREA INSTITUE OF SCIENCE AND TECHNOLOGY(KIST)

A Korean research team has developed a technology that enables the effective control of fine particulate matter and nanoplastics, which are major causes of human toxicity and ecosystem disturbances. This technology, which allows for real-time sorting, purification, and concentration of nanoparticles invisible to the human eye, has great potential application, not only for the removal of toxic particles from the natural environment, but also for removing viruses and detecting dementia-related proteins and cancer diagnostic markers. Due to its vast range of applicability, this technology is attracting much attention in scientific and academic circles.

The research team, led by Dr. Yong-sang Ryu of the Sensor System Research Center in the National Agenda Research Division at the Korea Institute of Science and Technology (KIST), working with a team led by Dr. Sin-Doo Lee of the Department of Electrical and Computer Engineering at Seoul National University (SNU, President Se-Jung Oh), announced its successful development of a '*nanogap electrode' able to effectively capture ultra-fine floating particles as small as 20 nanometers (nm, 1/1000 the thickness of a human hair). The research team used the newly developed electrode in successful selective concentration and positioning experiments for **extracellular vesicles (exosomes), which have recently been gaining much attention in the new drug development field and as new diagnostic markers for cancer as well as dementia-related proteins (***Amyloid-beta).

*Nanogap electrode: Electrode with a nanometer-scale gap between two electrodes.

**Extracellular vesicle: Also called an exosome. A single-membraneparticle released from a cell, in the shape of a flattened pocket.

***Amyloid-beta: A representative dementia-causing protein, usually found in the brain cells of dementia patients.

Researchers around the world have shown a keen interest in developing techniques to manipulate nano-size particles without damaging them. The optical tweezers technology, which received the Nobel Prize in Physics in 2018, is representative of such technologies. However, it has proven difficult to go beyond individual particle-level manipulation/measurement and to realize commercialization on a massive scale. Researchers have repeatedly run into technical limitations in scaling mechanisms for collecting, sorting, purifying, and concentrating particles that are 100 nm or less in size; however, such mechanisms are needed to work in large-scale atmospheric and water environments.

The joint KIST-SNU research team, through centimeter (cm) scale device production for particle concentration and purification experiments, was able to overcome these limitations and successfully scaled up the nanogap electrodes by sandwiching nanoscaled insulator film between two electrodes in a vertical alignment, allowing the 'dielectrophoretic tweezer' technology to be applied to large areas. Dielectrophoresis is a technology wherein wavelengths vibrating several hundred to several thousand times per second are applied to two electrodes to form an non-uniform electrical field distribution around the electrodes. These electrodes are then used to attract or repel particles in the vicinity of the nanogaps.

The joint research team conducted experiments to find technologies that could use universally available semiconductor processes, rather than expensive equipment used only by select companies. During the experiment process, the team found that the dielectrophoretic force produced by electrodes in an asymmetric electrode-arranged vertical array was over 10 times greater than that of a conventional horizontally-aligned nanogap array. This discovery simultaneously solved the problems of scaling up and reduced the costs associated with the nanogap technology. Using the conventional horizontal electrode array production method, it costs a minimum of several hundreds of thousands of won to produce enough nanogap electrodes to cover the area of a fingernail. Using the new dielectrophoresis technology, it takes only KRW 5,000 to produce enough nanogap electrodes to cover the area of an LP disc.

The vertical nanogap technology developed by the KIST research team makes it possible to scale up the nanogap electrode technology, produce nanogap electrodes in numerous shapes and sizes, and radically reduces unit production costs. As such, the technology has a broad range of potential applications. According to the research team, when used in air or water filters, the nanogap electrodes can function under low voltage (such as that of an ordinary AA cell) to detect and remove, in real time, various microscopic floating particles such as fine dust, nanoplastics, viruses, germs, and bacteria.

Dr. Eui-Sang Yu, the principle author of the study, commented, "The achievement has future application for the sorting and purifying of nano-sized particles, regardless of type of particle or the environment." Dr. Yong-Sang Ryu of the KIST, the corresponding author of the study, added, "We hope that the study can make broad contributions to solving various social problems and enhance the general quality of human life."

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The research, backed by the Ministry of Science and ICT (MSIT), was conducted as an Institutional Research Program of the Korea Institute of Science and Technology (KIST) and as part of a Samsung Research Funding & Incubation Center for Future Technology project. The study was published in the latest issue of Nature Communications (IF: 11.878, JCR top 6.52%), the most respected journal in nano-bio convergence technologies.

Insights into climate change during origin of dinosaurs

An international team reveals discoveries about an unusual time called the 'Carnian Pluvial Episode'

UNIVERSITY OF UTAH

IMAGE: A DINOSAUR-LIKE REPTILE LEAVES MUDDY FOOTPRINTS ALONG THE SHORELINE OF A LAKE DURING A RAINSTORM SOME 234 MILLION YEARS AGO IN NORTHWESTERN ARGENTINA. view more 

CREDIT: JORGE GONZALEZ/NHMU

The Triassic Period, about 252 to 201 million years ago, was a time of volatile change, particularly during an interval known as the Carnian (about 237 to 227 million years ago). Three dramatic events occurred on Earth: the first dinosaurs appeared, gigantic volcanic eruptions called the Wrangellia large igneous province spewed out greenhouse gasses and the climate suddenly shifted to warmer, more humid conditions that scientists call the Carnian Pluvial Episode (CPE).

Recent work suggests that the Wrangellia eruptions caused the CPE, and that the resulting climate change may have spurred the early diversification of dinosaurs. But the lack of precise absolute dates for many Carnian sediments makes comparisons difficult. Additionally, few detailed paleoclimatic data exist for many regions outside of Europe, making it unclear whether the CPE was truly a global climate event or conclusively linking it to dinosaur diversification.

In a new study in the journal Gondwana Research, an international group led by Adriana Mancuso, a National Scientific and Technical Research Council (CONICET) researcher at the Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales in Mendoza, Argentina, demonstrated that the CPE affected the southern hemisphere, specifically South America, which strengthens the case that it was a global climate event. The study was published online on June 15, 2020.

"There are ample Triassic, and specifically Carnian, rocks and fossils in South America, and Argentina in particular, but until now there were no paleoclimatic studies that could conclusively show that the Carnian Pluvial Episode occurred in the southern hemisphere," Mancuso said.

The team, which included researchers at the University of Utah and the Berkeley Geochronology Center, studied Carnian rocks of the Los Rastros Formation, which are preserved in the Ischigualasto-Villa Unión Basin in northwest Argentina. For the first time, the team precisely dated volcanic ash preserved in lake sediments and pieced together the paleoclimate at this time.

"Our study focused on these rocks because they had the perfect combination of a good fossil record, dateable ash layers, and rich climate data preserved in lake sediments," said Randall Irmis of the Natural History Museum of Utah and Department of Geology & Geophysics at the University of Utah.

In order to date the ash layer, the scientists isolated small needle-like crystals of zircon, minerals that act like time-capsules. When zircon crystallizes during an eruption, it traps the element uranium in its crystal structure, but never incorporates lead. Any lead preserved in the crystals today is a result of the radioactive decay of uranium. Because scientists know this decay rate, they can measure the ratio of uranium and lead in each zircon crystal and calculate how far back in time the crystals formed. In the present study, this measurement was done on a precise mass spectrometer at the Berkeley Geochronology Center.

The scientists then obtained paleoclimatic data by looking at detailed features in the sediments-- the types of clay preserved, and carbon and oxygen isotopes in freshwater limestone layers. With these measurements, the researchers estimated temperature, humidity and aridity and observed a distinct interval of particularly warm and humid conditions. Based on the absolute date from the same strata, they concluded that it matched in time with the CPE in the northern hemisphere. By using a variety of different analyses, the resulting paleoclimate inferences were more robust than previous assertions made from a single line of evidence.

This warm/humid interval also fortuitously includes layers that preserve fossil footprints of early dinosaurs or their closest relatives.

"Our study suggests that the appearance of dinosaurs in South America could be linked to the CPE, but the data available worldwide remains inconclusive. To make a more robust global link between the CPE and dinosaur diversification will require many more detailed studies of paleoclimate with precise ages like we were able to do for the Los Rastros Formation in Argentina," concluded Mancuso.

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Other authors include Cecilia Benavente of the Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales (CONICET) and Roland Mundil of the Berkeley Geochronology Center.

Burrowing crabs reshaping salt marshes, with climate change to blame

BROWN UNIVERSITY

 

IMAGE: A NEW STUDY REVEALS HOW CLIMATE CHANGE HAS ENABLED A VORACIOUS CRAB SPECIES TO DRAMATICALLY ALTER SALT MARSH ECOSYSTEMS ACROSS THE SOUTHEASTERN U.S. THE STUDY, PUBLISHED IN PROCEEDINGS OF THE... view more 

CREDIT: CHRISTINE ANGELINI

PROVIDENCE, R.I. [Brown University] -- A new study reveals how climate change has enabled a voracious crab species to dramatically alter salt marsh ecosystems across the southeastern U.S.

The study, published in Proceedings of the National Academy of Sciences, shows that soils beneath salt marshes from South Carolina to Florida have been softened by higher sea levels and increased tidal inundation. That softening has allowed the burrowing crab species Sesarma reticulatum to thrive, feeding on the cordgrass that holds the marshes together.

The clearing of grass by crabs has dramatically altered the flow of creeks that run through the marshes, the study found, and is altering the dynamics between predator and prey species in the marshes. In fact, the researchers say that Sesarma, which had previously been a minor player in southeastern salt marshes, can now be considered a keystone species, meaning it plays a dominant role in shaping the ecosystem.

"What we've found is an example of how sea level rise can activate a keystone species that's now dramatically remodeling these salt marshes," said Mark Bertness, a professor emeritus of ecology and evolutionary biology at Brown University and a coauthor of the research. "That's a big deal because sea level rise is a pervasive global phenomenon, and this is a largely unexpected consequence. We need to start thinking about how global climate change could activate new keystone species in other ecosystems."

Research on Sesarma crabs and their impact on salt marshes has a long history in Bertness's lab at Brown. In 2011, Bertness and his students discovered that Sesarma, voracious grazers of cordgrass roots and leaves, were behind sudden die-offs of marshes on Cape Cod. In that case, overfishing had suddenly pulled predator species like striped bass out of the water, giving the crabs free reign to decimate the marshes. One of the undergraduate co-authors on that earlier research was Christini Angelini, now an associate professor at the University of Florida and a senior author on this new paper.

Sesarma were known to inhabit southern marshes in Florida and the Carolinas, but their populations hadn't boomed like those further north. One potential reason for that was differing soil substrates. While working several years ago as an undergraduate researcher in Bertness' lab, Sinead Crotty, now project director at Yale's Carbon Containment Lab, showed that ground hardness played a big role in where Sesarma are able to establish themselves. Her findings indicated that Sesarma had a much easier time building burrows and feeding on grass roots in the peaty New England soil compared to harder soil substrates often found in southern marshes.

But as sea levels continue to rise due to climate change, Crotty, Angelini and Bertness wondered if softening soils might be giving Sesarma more of a foothold in the South. Looking at aerial photos from nine locations across South Carolina and Florida, they found that the number of marsh creeks with evidence of Sesarma grazing increased by up to 240% from the late 1990s to the late 2010s. Meanwhile, surveys of sea level rise show that the ground in these areas is tidally submerged up to an hour longer per day now compared to the late 1990s.

"You've got the sea level rising, which softens the substrate that these crabs usually can't burrow in," Bertness said. "Now that it's softer you've got an ideal habitat to support these huge communal Sesarma burrows."

This new Sesarma activity is reshaping marshes, the researchers found. Elimination of grasses has increased the rate at which creeks form in the marshes, and increases the drainage density of marsh creeks by up to 35%.

Sesarma activity is also influencing interactions between predators and prey in the creeks. Clearing of grasses provides predators increased access to shellfish and other prey species. The research found that populations of mussels were dramatically lower in Sesarma-grazed creeks compared to creeks that weren't grazed.

"As they drown, southeastern U.S. marshes are fracturing from grasslands to patches of marsh, with depleted populations of mussels, snails and other invertebrates," Angelini said. "These dynamics reveal how quickly marshes may disappear with accelerating sea level rise and how long they will remain foraging grounds for commercially, recreationally and ecologically important species."

The fact that Sesarma is now altering the geomorphology of the marshes, as well as the ecological interactions between other species, is evidence that it now qualifies as a keystone species in southern marshes. This is the first example, the researchers say, of activation of new keystone species as the result of anthropogenic climate change.

"This is going to be something for the textbooks," Bertness said. "This is an underappreciated way in which climate change alters ecosystems."

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Other authors on the paper were Collin Ortals, Thomas Pettengill, Luming Shi, Maitane Olabarrieta, Matthew Joyce, Andrew Altieri, Elise Morrison, Thomas Bianchi and Christopher Craft. The research was supported by the National Science Foundation (1652628, 1546638, 1315138).

Meditation linked to lower cardiovascular risk

Survey data from more than 61,000 people points to heart benefits

VETERANS AFFAIRS RESEARCH COMMUNICATIONS

 

IMAGE: MARTY SIGEL, A 77-YEAR-OLD NAVY VETERAN, TRIES OUT SOME MEDITATION ON A JULY DAY IN BALTIMORE. NEW RESEARCH HAS ADDED TO THE EVIDENCE ON THE CARDIOVASCULAR BENEFITS OF MEDITATING.... view more 

CREDIT: MITCH MIRKIN

Meditation was linked to lower cardiovascular risk in a data analysis by Veterans Affairs researchers and colleagues.

The results appeared online June 30 in the American Journal of Cardiology.

Previous studies have suggested that meditation may have beneficial effects on a number of conditions. A 2017 American Heart Association scientific statement suggests that meditation may be of benefit for cardiovascular risk reduction. Data show that it may help with blood pressure, cholesterol level, quitting smoking, and overall cardiovascular health. However, this connection is far from definitive. By using a large national database with many participants, the authors of the new study sought further evidence on how meditation impacts cardiovascular risk.

Lead researcher Dr. Chayakrit Krittanawong--of the Michael E. DeBakey VA Medical Center, Baylor College of Medicine, and the Icahn School of Medicine at Mount Sinai--and his colleagues studied data from the National Health Interview Survey, conducted annually by the National Center for Health Statistics. It collects information on a wide range of health topics from a nationally representative sample.

The researchers looked at data on more than 61,000 survey participants. Of those, almost 6,000 (nearly 10%) said they participated in some form of meditation.

The researchers found that people who meditated had lower rates of high cholesterol, high blood pressure, diabetes, stroke, and coronary artery disease, compared with those who did not meditate.

The greatest difference was in coronary artery disease. Those who meditated were 51% as likely as those who didn't to have the disease. The prevalence of other cardiovascular risks in the meditation group compared with the non-meditation group was 65% for high cholesterol, 70% for diabetes, 76% for stroke, and 86% for high blood pressure.

The researchers controlled for other factors connected to cardiovascular risk, such as age, sex, cigarette smoking, and body mass index. After adjusting for these factors, the effect of meditation was still significant.

Many types of meditation exist. Most focus on attention and awareness. Meditation has been shown to increase physical and mental relaxation. "I believe in meditation, as it can give us a sense of calm, peace, and stress reduction, leading to improvement of our emotional well-being," explained Krittanawong.

Practicing meditation has been linked to decreased stress, greater mindfulness, and improved psychological health. It may even lead to long-term functional and anatomical changes in the brain. Meditation is also simple, cost-effective, and low-risk.

Krittanawong and colleagues did note several limitations to the study. First, the survey did not capture what type of meditation people were using. Some types of meditation may offer more cardiovascular benefit than others, say the researchers. The survey also did not ask about the duration or intensity of that meditation. It is possible that those who practice longer and more frequently will get more benefit, but the study cannot measure these effects.

Also, the researchers cannot definitively say that meditation directly decreases cardiovascular risk. It could be that people who are in better cardiovascular health to begin with are more likely to practice meditation, rather than the other way around.

Other life activities might also obscure the link between meditation and cardiovascular health. The researchers found factoring in alcohol consumption and physical activity lowered the significance of the relationship between meditation and cardiovascular risk.

Considering all these factors, the researchers concluded that meditation is "probably" associated with lower prevalence of cardiovascular risk. Krittanawong notes that, while the results suggest that meditation can improve cardiovascular health, "we would need a powerful study such as a clinical trial to determine whether meditation could benefit cardiovascular health in veterans."

Meanwhile, the study adds to a growing body of research on the potential benefits of meditation, they say.

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The study authors are from the Michael E. DeBakey VA Medical Center, Baylor College of Medicine, the Icahn School of Medicine at Mount Sinai, the Cleveland Clinic, and the Mayo Clinic.

For more information about VA research on meditation, visit the Complementary and Integrative Health topic page on the VA research website: http://www.research.va.gov/topics/cih.cfm.

Pickled capers activate proteins important for human brain and heart health

New study reveals how a compound found in capers regulates proteins that control important bodily processes

UNIVERSITY OF CALIFORNIA - IRVINE

 

IMAGE: PICKLED CAPERS USED IN THIS STUDY WERE FOUND TO ACTIVATE KCNQ CHANNELS IMPORTANT FOR NORMAL HUMAN BRAIN AND HEART ACTIVITY. view more 

CREDIT: BO ABBOTT

Irvine, CA - July 13, 2020 - A compound commonly found in pickled capers has been shown to activate proteins required for normal human brain and heart activity, and may even lead to future therapies for the treatment of epilepsy and abnormal heart rhythms.

Researchers from the University of California, Irvine School of Medicine have discovered that a compound named quercetin, commonly consumed when eating capers, can directly regulate proteins required for bodily processes such as the heartbeat, thought, muscular contraction, and normal functioning of the thyroid, pancreas and gastrointestinal tract.

Published in Communications Biology, the discovery was made by the laboratory of Geoffrey Abbott, PhD, a professor in the Department of Physiology and Biophysics at the University of California, Irvine School of Medicine. Kaitlyn Redford, a graduate student in the Abbott Lab, was first author of the study titled, "The ubiquitous flavonoid quercetin is an atypical KCNQ potassium channel activator."

The Abbott Lab found that quercetin, a plant-derived bioflavonoid, modulates potassium ion channels in the KCNQ gene family. These channels are highly influential in human health and their dysfunction is linked to several common human diseases, including diabetes, cardiac arrhythmia, and epilepsy.

The study revealed that quercetin modulates the KCNQ channels by directly regulating how they sense electrical activity in the cell, suggesting a previously unexpected mechanism for the therapeutic properties of capers. The mechanism may extend to other quercetin-rich foods in our diet, and quercetin-based nutritional supplements.

"Now that we understand how quercetin controls KCNQ channels," said Abbott, "future medicinal chemistry studies can be pursued to create and optimize quercetin-related small molecules for potential use as therapeutic drugs."

The Abbott Lab screened plant extracts for the ability to alter activity of KCNQ channels and found that one percent extract of pickled capers activated channels important for normal human brain and heart activity. Further studies revealed the molecular mechanism - quercetin from the caper extract binds to a region of the KCNQ channel required for responding to electrical activity, and in doing so, tricks the channel into opening when it would normally be closed.

"Increasing the activity of KCNQ channels in different parts of the body is potentially highly beneficial," said Abbott. "Synthetic drugs that do this have been used to treat epilepsy and show promise in preventing abnormal heart rhythms."

Archaeological evidence for human caper consumption dates back as far as 10,000 years, according to archaeological findings from Mesolithic soil deposits in Syria and late Stone Age cave dwellings in the Greece and Israel. Capers have traditional been used as folk medicine for hundreds if not thousands of years and are in current use or study for their potential as anti-cancer, anti-diabetic and anti-inflammatory properties, and their possible circulatory and gastrointestinal benefits.

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This study was supported by the National Institutes of Health, National Institute of General Medical Sciences and National Institute of Neurological Disorders and Stroke.

About the UCI School of Medicine

Each year, the UCI School of Medicine educates more than 400 medical students, and nearly 150 doctoral and master's students. More than 700 residents and fellows are trained at UCI Medical Center and affiliated institutions. The School of Medicine offers an MD; a dual MD/PhD medical scientist training program; and PhDs and master's degrees in anatomy and neurobiology, biomedical sciences, genetic counseling, epidemiology, environmental health sciences, pathology, pharmacology, physiology and biophysics, and translational sciences. Medical students also may pursue an MD/MBA, an MD/master's in public health, or an MD/master's degree through one of three mission-based programs: the Health Education to Advance Leaders in Integrative Medicine (HEAL-IM), the Leadership Education to Advance Diversity-African, Black and Caribbean (LEAD-ABC), and the Program in Medical Education for the Latino Community (PRIME-LC). The UCI School of Medicine is accredited by the Liaison Committee on Medical Accreditation and ranks among the top 50 nationwide for research. For more information, visit som.uci.edu.

Study links attraction to 'tyrannical' leaders to dysfunctional family dynamics

Adolescent family conflict could play a role in the types of leaders people follow as adults

SAN FRANCISCO STATE UNIVERSITY

 

Ever wonder how some leaders in business or politics who appear selfish, manipulative and domineering still manage to amass a following? A recent study in the Journal of Leadership & Organizational Studies by San Francisco State University Assistant Professor of Management Dayna Herbert Walker found a connection between a person's childhood family environment and the types of leaders they're drawn to as grown-ups.

Using data from the Fullerton Longitudinal Study, a long-term study that began tracking families in 1979, Herbert Walker and three other researchers noticed a correlation between adolescents who reported a high level of conflict at home and those who later identified socially undesirable traits as ideal leadership qualities.

"We see it all the time -- where the obnoxious leader rises to the top, but we don't know much about why," Herbert Walker said. "Tyrants, whether they be in the boardroom or in politics, wouldn't have the power they do if followers didn't support them. We often look to leaders to explain leadership, but we should also be looking to followers."

The survey, which tracked 130 individuals at various points of their life, gave researchers details about participants' home lives and the leadership traits they valued most. Researchers studied data gathered in 1996, when participants were 17 years old. Two decades later, as part of another round of data collection for the Fullerton Longitudinal Study, researchers asked the same individuals questions about ideal leadership qualities.

The 1996 survey asked participants about their family dynamics, such as whether people at home raised their voices, criticized one another or were physically violent. Twenty years later, those respondents were asked to measure on a scale whether 10 qualities researchers defined as tyrannical (domineering, pushy, dominant, manipulative, power-hungry, conceited, loud, selfish, obnoxious and demanding) were characteristics present in their image of an ideal leader.

"It's critical that we asked about ideal leadership and not just leadership in general," Herbert Walker said, "because we really wanted to get at a person's favored leadership image, the characteristics they ideally want to see in their leaders."

Herbert Walker and the study's other authors then compared the data from 2016 and 1996 and found a strong positive connection between those who reported living with a high level of conflict at home and those whose ideal image of a leader possessed these negative traits. A person who experiences high conflict in adolescence is 20% more likely than chance to prefer a tyrannical model of leadership, controlling for other known factors that shape leadership preferences like sex and personality. When adolescent family environments contain a high amount of dysfunctional conflict, it's likely that some tyrannical behavior is on display and that role modeling can shape the way a person views leadership, Herbert Walker explains.

The findings shed new light on what ideal leadership can look like for some followers, illuminating why some of us are drawn to tyrants despite their harsh approach.

Herbert Walker says another group could learn important lessons from the findings, as well: bad bosses. For instance, a manager who believes leaders should be overbearing or manipulative could end up acting out those traits.

"The first step is getting them to question their assumptions about why they do what they do," she said. "Maybe they'll realize that they believe this, because that's how their dad behaved and he was successful in business. And so they believe that's how they're supposed to act."

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