Consumer-created social media visuals capture consumer brand perceptions

Researchers analyzed consumer- and firm-created brand imagery to examine gaps in consumer brand perceptions and firm brand positionings

INSTITUTE FOR OPERATIONS RESEARCH AND THE MANAGEMENT SCIENCES

 

Key Takeaways:

• Social media visuals are overtaking text in defining online brand conversations.
• User-generated visuals are reflective of consumer brand perceptions.
• Researchers developed a new model called BrandImageNet to map images to perceptual attributes of a brand.
• Firms can use the BrandImageNet model to automatically monitor consumers' brand perceptions and examine the effectiveness of their positioning strategies.

CATONSVILLE, MD, July 13, 2020 - New research has found that there is a strong link between the visual portrayal of a brand in online imagery created by consumers and the larger brand perceptions.

The research study, to be published in the July/August issue of the INFORMS journal Marketing Science, is titled "Visual Listening In: Extracting Brand Image Portrayed on Social Media" and is authored by Liu Liu of the University of Colorado, Daria Dzyabura of the New Economics School in Russia, and Natalie Mizik of the University of Washington.

According to the authors, their research sought to measure how brands are portrayed on social media and how it relates to brand perceptions. Their goal was to better understand consumer brand perceptions and attitudes toward brands reflected in the imagery consumers post on digital platforms.

"Consumer-created brand images on social media are different from product images on retailer websites," said Liu. "Consumer-created brand imagery posted on social media depicts consumers' interactions with brands and links brands with usage context, feelings, and consumption experiences."

The researchers argued that these consumer-generated images send a powerful message as a form of testimonial for other consumers. They also offer the brand owners the opportunity to understand consumers' brand perceptions.

"In much of the prior research in this area, the focus has been on text content," said Liu. "Given that images are on their way to surpassing text as the medium of choice for online conversations, monitoring visual content is important to get a more complete understanding of online conversations involving brands."

In the process, the researchers introduced a "visual listening in" approach to monitor visual brand content that was created and shared by the actual consumers on social media. They developed and validated a model, BrandImageNet, to allow firms to monitor their brand portrayal on social media and evaluate it relative to competitors' and their own firm's desired brand positioning.

"Our BrandImageNet model maps images to specific perceptual attributes," said Liu. "We focused on identifying perceptual brand attributes rooted in brand images. This is different from identifying functional attributes of the product itself. One example we use in our research is a comparison between the Prada and Eddie Bauer brands. Which one is portrayed by social media users, visually, as the more glamorous and which one is the more rugged one? Our model unequivocally points to Prada as glamorous and Eddie Bauer as rugged. Across all brands in our study, we find a strong link between model predictions and consumer brand perceptions collected with traditional survey-based methods."

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About INFORMS and Marketing Science

Marketing Science is a premier peer-reviewed scholarly marketing journal focused on research using quantitative approaches to study all aspects of the interface between consumers and firms. It is published by INFORMS, the leading international association for operations research and analytics professionals. More information is available at http://www.informs.org or @informs.

Domestic violence increased in the great recession

UC Davis study suggests preparing for similar issues in COVID-19

UNIVERSITY OF CALIFORNIA - DAVIS

 

IMAGE: A FIGURE FROM THE STUDY SHOWS INCIDENTS OF DOMESTIC VIOLENCE THAT REQUIRED EITHER AN EMERGENCY ROOM VISIT OR HOSPITALIZATION BY RATES PER 100,000 OF POPULATION. THE NUMBERS SHOW A MARKED... view more 

CREDIT: COURTESY OF STUDY RESEARCHERS

Emergency room visits for domestic violence incidents in California more than tripled during the Great Recession compared to the years before, signaling a need to prepare for similar and more prolonged effects during the COVID-19 financial crisis, suggest University of California, Davis, researchers.

Conducting one of the first studies to date examining the impact of a modern recession on hospital and emergency room visits, researchers found that physical abuse in adults increased substantially between the time periods, with Black and Native American people being disproportionately affected. Violence against children did not show a marked increase. The results were published in Preventive Medicine in June.

"The results from our study shine a spotlight on the importance of domestic-violence-related screening, prevention and response during the next several months of the COVID-19 financial effects," said the study's primary author, Alvaro Medel-Herrero, project scientist for the UC Davis Center for Health and the Environment. "Notably, domestic violence is grossly under-reported, and cases that end up in the emergency room or result in a hospital stay are only the most egregious examples. This tells us there may be an even larger problem than the numbers can show."

The study's co-authors included Suzette Smiley-Jewel, of the UC Davis School of Veterinary Medicine; Martha Shumway, Department of Psychiatry, University of California, San Francisco; Amy Bonomi, Michigan State University; and Dennis Reidy, School of Public Health, Georgia State University.

Study looked at 53,000 domestic violence episodes

The study's authors looked at more than 53,000 domestic-violence-related episodes, composed of both intimate partner violence as well as violence against elders and children, between 2000 and 2015. The numbers were drawn from California's Office of Statewide Health Planning and Development, or OSHPD, and then broken down between the years during, before and after the Great Recession. While the Great Recession officially lasted less than two years, from December 2007 to June 2009, during which the gross domestic product contracted, the economic crisis produced long-lasting consequences for individuals as well as society as a whole, researchers said.

"Proactive outreach is especially needed for minoritized people, who may be especially isolated, experiencing disconnections from services, and facing extreme financial stress," said one of the co-authors, Bonomi, of Michigan State University.

Blacks more than three times more likely to be victims

Time series for the study were divided into pre-recession (January 2000-November 2007) and recession/post-recession (December 2007-September 2015) periods. Blacks were more than three times more likely to suffer domestic violence during the recessionary period when compared with other segments of the California population, according to the data. Statistics showed that there were 3.58 emergency room visits per 100,000 population compared to 10.42 emergency visits per 100,000 people for Blacks. Hospitalization rates remained relatively similar from the pre-recession as compared to the recession/post-recession period except for Native Americans, which nearly doubled.

Emergency visits vastly exceeded hospitalizations during the 2007-2015 time period.

Additionally, the number of California police calls for weapon-involved domestic violence episodes steadily increased from 2008 (65,219) to 2014 (75,102).

Costs associated with domestic violence

For the period analyzed (2000-2015), the estimated total charge for all analyzed domestic violence hospitalizations was more than $1 billion (data was not available for emergency department costs).

Length of hospital stays slightly increased during the recession/post-recession period as compared to the pre-recession period, yet the inflation-adjusted charge per hospitalization dramatically increased over time, according to the study.

Domestic violence rate does not correspond with other hospital visits

It is important to note that the described increase in domestic-violence-related hospitalizations during the recession does not correspond to a general trend in health care in California. For example, California cancer hospital rates dropped during the Great Recession, according to OSHPD data. However, an increasing demand for emergency care during the recession and post-recession period has been reported and may reflect limitations in accessing care in other parts of the health care system, researchers said.

The authors' research will continue.

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The research was supported by a UC Davis Feminist Research Institute seed grant.

Full study available: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7315959/

Large Lot Program shows the power of private land stewardship in addressing urban vacancy

USDA FOREST SERVICE - NORTHERN RESEARCH STATION

IMAGE: SCIENTISTS WITH THE USDA FOREST SERVICE AND THE UNIVERSITY OF ILLINOIS FOLLOWED CHICAGO'S LARGE LOTS PROGRAM OVER 5 YEARS TO EXAMINE THE VISUAL AND SOCIAL EFFECTS OF RESIDENT-DRIVEN URBAN GREENING... view more 

CREDIT: USDA FOREST SERVICE PHOTOGRAPH

In the past 5 years, Chicago residents have purchased nearly 1,300 vacant lots and replaced weed trees and sagging fences with gardens and children's play areas. In doing so, they have demonstrated that transferring city-owned vacant lands to local residents can be a successful strategy for cities seeking to reduce blight and strengthen neighborhoods.

In assessing the potential benefits of the City of Chicago's "Large Lot Program," a team led by scientists Paul Gobster of the USDA Forest Service's Northern Research Station and William Stewart of the University of Illinois examined the visual and social effects of resident-driven urban greening efforts in high-vacancy areas of the city's south and west sides. In their most recent paper, published last week in the journal Landscape and Urban Planning, the research team found that the program has resulted in continued improvements in the condition and care of the purchased "large lots" over a 5-year period and that these improvements were consistent across all five community areas studied.

"While planners around the world are experimenting with ways to address urban vacancy, few cities have the tools to assess how well their programs work after they are implemented," Gobster said. "In this latest paper we develop a practical monitoring tool, the condition-care scale, and detail how it can be implemented by planners to assess the progress of vacant lot repurposing programs. The scale also holds promise for other applications related to urban greening and we encourage others to adapt it to their particular needs.

Previously reported findings from the study showed that visible changes to large lots in the year after purchase Ied to increases in lot "cues to care" including ornamental and vegetable gardens and social and recreational features, and that levels of lot condition and care were highest for owners who lived closest to their purchased large lot.

"In focus groups and a mail survey of large lot owners, we also found that residents who are improving the lots are gaining a stronger sense of place and belonging to their neighborhood, and they see the program is fulfilling community goals," Stewart said. "Together our visual and social assessments show that ownership matters, and that through private stewardship of vacant neighborhood lands the Large Lot Program is helping to address issues of environmental and economic justice in communities that have been disenfranchised for decades." The researchers' next step is to try and quantify whether participating in the Large Lot Program is leading to broader social outcomes, including reductions in crime.

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The City of Chicago collaborated with community groups to launch the Large Lot Program in 2014. Initially focused on the Greater Englewood area on the city's south side, the program aims to reduce the inventory of more than 11,000 city-owned vacant lots by offering them to neighbors for $1; nearly 1,300 vacant lots have been purchased to date.

Co-authors of the new paper, "The Condition-Care Scale: A Practical Approach to Monitoring Progress in Vacant Lot Stewardship Programs," include Alessandro Rigolon of the University of Utah and Sara Hadavi of Kansas State University. The paper is available through the Northern Research Station at https://www.nrs.fs.fed.us/pubs/60442

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news rele

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).