Tech

A team of researchers have examined whether urban red maples - a resilient native tree known to thrive in urban environments - acclimate to environmental shifts and whether that response is impacted by the size of the city.

They found that trees in larger cities are actually healthier and more productive than those in less dense areas.

To determine how trees respond to different urban intensities, the team - which includes researchers from the University of Delaware - compared forests in Newark, Del., to those in Philadelphia, Pa. In forest fragments that make up the FRAME network in each city, data was collected to measure tree size and age, foliage nitrogen signature, nutrient and heavy metal content, and stress-responding metabolites, as well as surrounding soil conditions.

Not only were the trees acclimated to urban conditions but the red maples in the higher density Philadelphia forests were actually healthier and more productive than those surrounded by less urbanization in Newark.

"We have different levels of nitrogen deposition due to fumes from vehicle tailpipes, construction materials are adding excess calcium into forest soils, carbon dioxide levels are elevated because of population density, and we have impervious surfaces like roads and buildings that are holding heat and warming up the city in a phenomenon we call urban heat island," said Covel McDermot, a University of Delaware alumnus and co-author of the study. "Our goal was to evaluate health and stress-indicating compounds in the leaves of red maple trees that face these conditions in forests embedded in a large, heavily urbanized city versus a small, fairly urbanized city."

People usually think that urban ecosystems are nutrient deficient, but we see that these systems have higher nutrient loads that support productivity.

For example, in Philadelphia there is a lot of construction using concrete. Concrete is a substance that contains calcium, magnesium and aluminum. As construction and deconstruction happen, as they often do in cities, these materials eventually break down and become available food sources for plants. Look at your wall. It's likely made of materials containing gypsum and those will eventually end up in the soil and become bioavailable to plants.

To build barriers to stressors like excessive heat or heavy metals, trees produce stress-shielding and signaling compounds which protect the chloroplast and mitochondria from oxidative stress, allowing the tree to flourish. However, there is a tradeoff in resources for growth and development versus permanent stress defense. Philadelphia soil conditions, unlike those in Newark that experienced degradation due to past agricultural practices, were more nutrient rich so those ecosystems held enough nitrogen to allow trees to produce additional stress-responding compounds while also growing into healthier, more productive forests.

McDermot hopes that this red maple study serves as the blueprint for future research on other species commonly found in urban systems.

"This gives us insight into planting the right trees in cities," McDermot said. "We can't just focus on beautification. We need to support ecological resilience. It's about prescribed greening -- planting the right tree species, in the right place, in the right soil conditions and for the right reasons."

In this year of extreme weather events -- from devastating West Coast wildfires to tropical Atlantic storms that have exhausted the alphabet -- scientists and members of the public are asking when these extreme events can be scientifically linked to climate change.

Dale Durran, a professor of atmospheric sciences at the University of Washington, argues that climate science need to approach this question in a way similar to how weather forecasters issue warnings for hazardous weather.

In a new paper, published in the October issue of the Bulletin of the American Meteorological Society, he draws on the weather forecasting community's experience in predicting extreme weather events such as tornadoes, flash floods, high winds and winter storms. If forecasters send out a mistaken alert too often, people will start to ignore them. If they don't alert for severe events, people will get hurt. How can the atmospheric sciences community find the right balance?

Most current approaches to attributing extreme weather events to global warming, he says, such as the conditions leading to the ongoing Western wildfires, focus on the likelihood of raising a false alarm. Scientists do this by using statistics to estimate the increase in the probability of that event that is attributable to climate change. Those statistical measures are closely related to the "false alarm ratio," an important metric used to assess the quality of hazardous weather warnings.

But there is a second key metric used to assess the performance of weather forecasters, he argues: The probably that the forecast will correctly warn of events that actually occur, known as the "probability of detection." The ideal probability of detection score is 100%, while the ideal false-alarm rate would be zero.

Probability of detection has mostly been ignored when it comes to linking extreme events to climate change, he says. Yet both weather forecasting and climate change attribution face a tradeoff between the two. In both weather forecasting and climate-change attribution, calculations in the paper show that raising the thresholds to reduce false alarms produces a much greater drop in the probability of detection.

Drawing on a hypothetical example of a tornado forecaster whose false alarm ratio is zero, but is accompanied by a low probability of detection, he writes that such an "overly cautious tornado forecasting strategy might be argued by some to be smart politics in the context of attributing extreme events to global warming, but it is inconsistent with the way meteorologists warn for a wide range of hazardous weather, and arguably with the way society expects to be warned about threats to property and human life."

Why does this matter? The paper concludes by noting: "If a forecaster fails to warn for a tornado there may be serious consequences and loss of life, but missing the forecast does not make next year's tornadoes more severe. On the other hand, every failure to alert the public about those extreme events actually influenced by global warming facilitates the illusion that mankind has time to delay the actions required to address the source of that warming. Because the residence time of CO2 in the atmosphere is many hundreds to thousands of years the cumulative consequences of such errors can have a very long lifetime."

UNIVERSITY PARK, Pa. -- Allegiance and loyalty to your country is highly valued in America, but what if you feel America doesn't love you back? New research examined whether feeling like you belong in America -- or not -- affected how members of different races and ethnicities participated in politics.

Ray Block Jr., associate professor of political science and African American studies at Penn State, said the study suggests that people who don't embody a typical white American identity may have complicated feelings of Americanness that may also affect their politics.

"We were able to get clues about how feelings of allegiance and belonging work together to affect how a person engages politically, for example by showing up to vote or by protesting," Block said. "Allegiance and belonging can mix together in meaningful ways to influence how much people are involved in a system that they feel they either belong to or which they feel might not love them back."

According to the researchers, the study -- recently published in the National Review of Black Politics -- was partially inspired by the current state of American politics and is important because a true democracy is based on everyone's voices being heard, not just those in majority demographics.

Block said that with debates surging about the separation of immigrant families, police brutality against Black Americans and other people of color, and a rise in white nationalism, he and the other researchers wanted to examine whether those in ethnic or racial minorities might have complicated feelings about their identity in America.

"We started with the idea that certain groups of Americans don't seem to have as much claim to Americanness as other groups do," Block said. "We noticed this in politics because sometimes people will weaponize American patriotism against outsiders. One of the ultimate ways to make someone an outsider is to question their Americanness. For example, when people questioned Colin Kaepernick taking a knee during the national anthem."

For the study, the researchers used data from the 2016 Collaborative Multiracial Post-Election Survey. The survey included 10,144 participants -- with 3,006 identifying as Asian, 3,102 as Black or African American, 3,002 as Latino/a, and 1,034 as white.

The researchers measured "Americanness" with two variables. The first was "belonging," measured by questions such as asking participants whether they felt most Americans valued their presence and whether they felt others tried to exclude them. The second was "allegiance," measured by asking how much being an American is important to them.

Finally, the researchers also looked at two forms of political participation: electoral and non-electoral. Electoral participation refers to actions such as voting and donating money to campaigns while non-electoral participation refers to actions such as signing petitions or participating in marches or protests.

"Non-electoral politics is usually the tool that those who feel voiceless use in politics," Block said. "Protesting and community activism, for example, might be what a person does when they feel outside the system. The more connected to the system you feel, the more likely you won't need non-electoral participation. But the less connected you feel you are to the system, the more appealing non-mainstream forms of political action become."

After analyzing the data, the researchers found that white respondents felt strongly that they belonged in America, while racial and ethnic minorities felt less belonging. Whites also reported higher levels of allegiance. When measuring political participation, whites reported the highest level of electoral participation.

When the researchers examined the connections between Americanness and electoral and non-electoral participation, Block said things got a little murkier. While the findings were statistically insignificant, he said the results still show patterns and clues to how feelings of allegiance and belonging may affect how someone participates politically.

For example, one pattern suggested that when a person's sense of belonging was low, allegiance had no connection to political participation. But when belonging was higher, there was the possibility that also feeling allegiance could increase a person's tendency to vote.

"This makes sense -- if electoral participation represents a very 'mainstream' type of activism, then why would anyone bother to take part in it if they do not think their society values/respects/includes them?" the researchers wrote in the paper. "Furthermore, the findings for non-electoral participation comport well with what we already know. The less highly regarded by their country people feel, the more appealing nonelectoral modes of activism become."

Scientists from NASA's Goddard Space Flight Center in Greenbelt, Maryland, and international collaborators demonstrated a new method for mapping the location and size of trees growing outside of forests, discovering billions of trees in arid and semi-arid regions and laying the groundwork for more accurate global measurement of carbon storage on land.

Using powerful supercomputers and machine learning algorithms, the team mapped the crown diameter - the width of a tree when viewed from above - of more than 1.8 billion trees across an area of more than 500,000 square miles, or 1,300,000 square kilometers. The team mapped how tree crown diameter, coverage, and density varied depending on rainfall and land use.

Mapping non-forest trees at this level of detail would take months or years with traditional analysis methods, the team said, compared to a few weeks for this study. The use of very high-resolution imagery and powerful artificial intelligence represents a technology breakthrough for mapping and measuring these trees. This study is intended to be the first in a series of papers whose goal is not only to map non-forest trees across a wide area, but also to calculate how much carbon they store - vital information for understanding the Earth's carbon cycle and how it is changing over time.

Measuring carbon in trees

Carbon is one of the primary building blocks for all life on Earth, and this element circulates among the land, atmosphere, and oceans via the carbon cycle. Some natural processes and human activities release carbon into the atmosphere, while other processes draw it out of the atmosphere and store it on land or in the ocean. Trees and other green vegetation are carbon "sinks," meaning they use carbon for growth and store it out of the atmosphere in their trunks, branches, leaves and roots. Human activities, like burning trees and fossil fuels or clearing forested land, release carbon into the atmosphere as carbon dioxide, and rising concentrations of atmospheric carbon dioxide are a main cause of climate change.

Conservation experts working to mitigate climate change and other environmental threats have targeted deforestation for years, but these efforts do not always include trees that grow outside forests, said Compton Tucker, senior biospheric scientist in the Earth Sciences Division at NASA Goddard. Not only could these trees be significant carbon sinks, but they also contribute to the ecosystems and economies of nearby human, animal and plant populations. However, many current methods for studying trees' carbon content only include forests, not trees that grow individually or in small clusters.

Tucker and his NASA colleagues, together with an international team, used commercial satellite images from DigitalGlobe, which were high-resolution enough to spot individual trees and measure their crown size. The images came from the commercial QuickBird-2, GeoEye-1, WorldView-2, and WorldView-3 satellites. The team focused on the dryland regions - areas that receive less precipitation than what evaporates from plants each year - including the arid south side of the Sahara Desert, that stretches through the semi-arid Sahel Zone and into the humid sub-tropics of West Africa. By studying a variety of landscapes from few trees to nearly forested conditions, the team trained their computing algorithms to recognize trees across diverse terrain types, from deserts in the north to tree savannas in the south.

Learning on the job

The team ran a powerful computing algorithm called a fully convolutional neural network ("deep learning") on the University of Illinois' Blue Waters, one of the world's fastest supercomputers. The team trained the model by manually marking nearly 90,000 individual trees across a variety of terrain, then allowing it to "learn" which shapes and shadows indicated the presence of trees.

The process of coding the training data took more than a year, said Martin Brandt, an assistant professor of geography at the University of Copenhagen and the study's lead author. Brandt marked all 89,899 trees by himself and helped supervise training and running the model. Ankit Kariryaa of the University of Bremen led the development of the deep learning computer processing.

"In one kilometer of terrain, say it's a desert, many times there are no trees, but the program wants to find a tree," Brandt said. "It will find a stone, and think it's a tree. Further south, it will find houses that look like trees. It sounds easy, you'd think - there's a tree, why shouldn't the model know it's a tree? But the challenges come with this level of detail. The more detail there is, the more challenges come."

Establishing an accurate count of trees in this area provides vital information for researchers, policymakers and conservationists. Additionally, measuring how tree size and density vary by rainfall - with wetter and more populated regions supporting more and larger trees - provides important data for on-the-ground conservation efforts.

"There are important ecological processes, not only inside, but outside forests too," said Jesse Meyer, a programmer at NASA Goddard who led the processing on Blue Waters. "For preservation, restoration, climate change, and other purposes, data like these are very important to establish a baseline. In a year or two or ten, the study could be repeated with new data and compared to data from today, to see if efforts to revitalize and reduce deforestation are effective or not. It has quite practical implications."

After gauging the program's accuracy by comparing it to both manually coded data and field data from the region, the team ran the program across the full study area. The neural network identified more than 1.8 billion trees - surprising numbers for a region often assumed to support little vegetation, said Meyer and Tucker.

"Future papers in the series will build on the foundation of counting trees, extend the areas studied, and look ways to calculate their carbon content," said Tucker. NASA missions like the Global Ecosystem Dynamics Investigation mission, or GEDI, and ICESat-2, or the Ice, Cloud, and Land Elevation Satellite-2, are already collecting data that will be used to measure the height and biomass of forests. In the future, combining these data sources with the power of artificial intelligence could open up new research possibilities.

"Our objective is to see how much carbon is in isolated trees in the vast arid and semi-arid portions of the world," Tucker said. "Then we need to understand the mechanism which drives carbon storage in arid and semi-arid areas. Perhaps this information can be utilized to store more carbon in vegetation by taking more carbon dioxide out of the atmosphere."

"From a carbon cycle perspective, these dry areas are not well mapped, in terms of what density of trees and carbon is there," Brandt said. "It's a white area on maps. These dry areas are basically masked out. This is because normal satellites just don't see the trees - they see a forest, but if the tree is isolated, they can't see it. Now we're on the way to filling these white spots on the maps. And that's quite exciting."

University of New Mexico researchers who combed through a "library" of previously approved drugs believe they have identified a medication with the potential to help speed a patient's recovery from SARS-CoV-2 infection.

"The gist of it is we think we found a drug that is on par with remdesivir and is much cheaper," said Tudor Oprea, MD, PhD, professor of Medicine and Pharmaceutical Sciences and chief of the UNM Division of Translational Informatics. Remdesivir is a relatively new antiviral medication that has been shown to shorten hospital stays for those recovering from the novel coronavirus.

In a paper published this week in ACS Pharmacology & Translational Science, Oprea and his colleagues, in partnership with a team at the University of Tennessee Health Science Center led by professor Colleen Jonsson, PhD, reported that an older antimalarial drug called amodiaquine was effective in eradicating the virus in test tube experiments.

Tudor Oprea, MD, PhDIt was one of three promising candidates identified in a process that entailed studying the molecular characteristics of about 4,000 drugs approved for human use by the Food and Drug Administration and other agencies. The researchers hoped to find drugs that would target known vulnerabilities in the virus.

The other two drugs - an anti-psychotic called zuclophentixol and a blood pressure medication called nebivolol also cleared the virus in the experiments, said Oprea, who served as the corresponding author on the new paper. The researchers think any of these three drugs could be combined with remdesivir or a related antiviral drug called favipiravir to mount a more potent attack on the virus.

Combining two drugs could mean that lower doses of each could be administered, lessening the likelihood of adverse reactions, he said.s Administering two drugs also makes it less likely that the virus would develop a mutation rendering it immune from the treatment.

"Think of it as a whack-a-mole game," Oprea said. "Instead of having one hammer, you have two hammers, which is more effective. We're trying to give the scientific community two hammers instead of one."

Many compounds that show antiviral activity in a laboratory setting don't have the same effect in living organisms, Oprea notes, so the next step is to mount clinical trials to see whether the medications work in COVID-positive patients.

The UNM drug screening process started with Oprea and his colleague Larry Sklar, PhD, Distinguished Professor in the Department of Pathology. They used computational methods to identify candidate drugs by gauging their similarity to hydroxychloroquine, a since-discredited antimalarial medication that had been widely touted as a COVID-19 treatment. Because of molecular variations in some of the drugs, more than 6,000 combinations were assessed.

Likely candidates were forwarded to Steven Bradfute, PhD, assistant professor in the Center for Global Health, who tested the compounds against samples of the virus in his Biosafety Level-3 laboratory. Later, the experiments were repeated by the University of Tennessee scientists to provide independent confirmation of the findings - and they used an additional test that reveals the drugs' potency against the virus, Oprea said.

Amodiaquine, first made in 1948, is on the World Health Organization's List of Essential Medicines. It has a good safety profile and is widely used in Africa to treat malaria. Zuclophentixol has been used to treat schizophrenia since the 1970s, while nebivolol has been used for hypertension since the late 1990s.

In a world first, researchers from the University of Ottawa in collaboration with Israeli scientists have been able to create optical framed knots in the laboratory that could potentially be applied in modern technologies. Their work opens the door to new methods of distributing secret cryptographic keys - used to encrypt and decrypt data, ensure secure communication and protect private information. The group recently published their findings in Nature Communications.

"This is fundamentally important, in particular from a topology-focused perspective, since framed knots provide a platform for topological quantum computations," explained senior author, Professor Ebrahim Karimi, Canada Research Chair in Structured Light at the University of Ottawa.

"In addition, we used these non-trivial optical structures as information carriers and developed a security protocol for classical communication where information is encoded within these framed knots."

The concept

The researchers suggest a simple do-it-yourself lesson to help us better understand framed knots, those three-dimensional objects that can also be described as a surface.

"Take a narrow strip of a paper and try to make a knot," said first author Hugo Larocque, uOttawa alumnus and current PhD student at MIT.

"The resulting object is referred to as a framed knot and has very interesting and important mathematical features."

The group tried to achieve the same result but within an optical beam, which presents a higher level of difficulty. After a few tries (and knots that looked more like knotted strings), the group came up with what they were looking for: a knotted ribbon structure that is quintessential to framed knots.

"In order to add this ribbon, our group relied on beam-shaping techniques manipulating the vectorial nature of light," explained Hugo Larocque. "By modifying the oscillation direction of the light field along an "unframed" optical knot, we were able to assign a frame to the latter by "gluing" together the lines traced out by these oscillating fields."

According to the researchers, structured light beams are being widely exploited for encoding and distributing information.

"So far, these applications have been limited to physical quantities which can be recognized by observing the beam at a given position," said uOttawa Postdoctoral Fellow and co-author of this study, Dr. Alessio D'Errico.

"Our work shows that the number of twists in the ribbon orientation in conjunction with prime number factorization can be used to extract a so-called "braid representation" of the knot."

"The structural features of these objects can be used to specify quantum information processing programs," added Hugo Larocque. "In a situation where this program would want to be kept secret while disseminating it between various parties, one would need a means of encrypting this "braid" and later deciphering it. Our work addresses this issue by proposing to use our optical framed knot as an encryption object for these programs which can later be recovered by the braid extraction method that we also introduced."

"For the first time, these complicated 3D structures have been exploited to develop new methods for the distribution of secret cryptographic keys. Moreover, there is a wide and strong interest in exploiting topological concepts in quantum computation, communication and dissipation-free electronics. Knots are described by specific topological properties too, which were not considered so far for cryptographic protocols."

The origins

The idea behind the project emerged in 2018, during a discussion with Israeli researchers at a scientific meeting in Crete, Greece.

Scientists from Ben-Gurion University of the Negev and Bar-Ilan University, in Israel, developed the prime number encoding protocol.

The project then crossed the Mediterranean Sea and the Atlantic Ocean before ending up in Dr. Karimi's lab located in the Advanced Research Complex at the University of Ottawa. That's where the experimental procedure was developed and conducted. The resulting data were then analyzed, and the braid structure extracted through a specially devised program.

The applications

"Current technologies give us the possibility to manipulate, with high accuracy, the different features characterizing a light beam, such as intensity, phase, wavelength and polarization," said Hugo Larocque. "This allows to encode and decode information with all-optical methods. Quantum and classical cryptographic protocols have been devised exploiting these different degrees of freedom."

"Our work opens the way to the use of more complex topological structures hidden in the propagation of a laser beam for distributing secret cryptographic keys."

"Moreover, the experimental and theoretical techniques we developed may help find new experimental approaches to topological quantum computation, which promises to surpass noise-related issues in current quantum computing technologies," added Dr. Ebrahim Karimi.

The eventual creation of replacement biological parts requires fully three-dimensional capabilities that two-dimensional and three-dimensional thin-film bioprinting cannot supply. Now, using a yield stress gel, Penn State engineers can place tiny aggregates of cells exactly where they want to build the complex shapes that will be necessary to replace bone, cartilage and other tissues.

"The reason why this is important is that the current cell aggregate bioprinting techniques can't make complicated configurations and is mostly in 2D and 3D thin films or simple configurations," said Ibrahim T. Ozbolat, Hartz Family Career Development Associate Professor of Engineering Science and Mechanics. "If we want complicated 3D, we need a supportive field."

That supportive field, the researchers report today (Oct. 16) in Communication Physics is a yield stress gel. Yield stress gels are unusual in that without stress they are solid gels, but under stress, they become liquid.

The researchers are using an aspiration-assisted bioprinting system that they demonstrated earlier this year to pick up aggregates of cells and place them precisely inside of the gel. The stress of the aspiration nozzle against the gel liquefies it, but once the aspiration nozzle releases cell aggregates and withdraws, the gel returns to solid again, self-healing. The tiny balls of cells rest upon each other and self-assemble, creating a solid tissue sample within the gel.

The researchers can place different types of cells, in small aggregates, together to form the required shape with the required function. Geometric shapes like the cartilage rings that support the trachea, could be suspended within the gel.

"We tried two different types of gels, but the first one was a little tricky to remove," said Ozbolat. "We had to do it through washing. For the second gel, we used an enzyme that liquefied the gel and removed it easily."

"What we are doing is very important because we are trying to recreate nature," said Dishary Banerjee, postdoctoral researcher in engineering science and mechanics. "In this technology it is very important to be able to make free-form, complex shapes from spheroids."

The researchers used a variety of approaches, creating theoretical models to get a physical understanding of what was happening. They then used experiments to test if this method could produce complex shapes.

An Edith Cowan University (ECU) study has revealed that a key blood marker of cancer could be used to select the most effective treatment for melanoma.

The discovery, which has the potential to improve melanoma survival rates, was published today in Clinical Cancer Research, a journal of the American Association for Cancer Research.

The research found that patients with high levels of circulating tumour DNA (ctDNA) - an important indicator of cancer in the blood - could potentially benefit from receiving a more aggressive treatment as a first line of defence against melanoma.

The study's lead researcher Associate Professor Elin Gray said the finding could help clinicians home in on effective melanoma treatments.

"Selecting the right course of drugs and therapies to treat melanoma is extremely complex and relies on a number of factors, including the characteristics of the tumour and how it has spread throughout the body," Associate Professor Gray said.

"This biomarker could help clinicians to better determine which patients would have better outcomes if we hit the cancer with an aggressive combination immunotherapy first."

Taking aim

Associate Professor Gray said while the research findings require validation in future studies, they highlight the need to carefully consider how biomarkers are used in melanoma treatment decisions.

"It's important to know when we should be targeting the cancer with certain types of drugs and which patients would benefit the most as aggressive treatments often result in more serious side effects," she said.

"This research will help clinicians to deliver personalised therapy regimens based on specific disease characteristics and the patient."

More clues

The study, part of the thesis of ECU PhD student Gabriela Marsavela, examined levels of the ctDNA biomarker in the blood of 125 metastatic melanoma patients recruited at Fiona Stanley Hospital and Sir Charles Gairdner Hospital in Perth, Western Australia, prior to undergoing immunotherapy. Results were validated in 128 patients recruited in collaboration with the Melanoma Institute Australia and Peter MacCallum Cancer Centre.

The research also found that the ctDNA biomarker cannot predict patient outcome in melanoma patients who received immunotherapy as a second line of treatment. Previous studies have shown that the marker is useful in predicting patient survival before the first line of treatment.

Associate Professor Gray said this finding is significant.

"While ctDNA can be used to indicate patient response to targeted first-round melanoma therapies, we now know that this biomarker cannot predict survival after second line treatment," she said.

"This means clinicians should use other ways of determining if a treatment will be successful or not."

Future of medicine

The new findings build on the ECU Melanoma Research Group's growing body of research investigating markers of cancer in the blood, also referred to as liquid biopsy. Study of these blood biomarkers is important in understanding how cancer spreads throughout the body.

According to Associate Professor Gray, further analysis of key biomarkers could hold the clues to unlocking future treatments.

"We have been battling to find new drugs and therapies to treat melanoma, but if we can find evidence that a particular drug can work for a tumour with particular characteristics, this could allow us to use existing drugs in a more targeted and precise way," she said.

Associate Professor Gray's team is now delving deeper into the characteristics of melanoma tumours that become resistant to therapy and why second-line treatments fail.

"This study really opened up a lot of questions and we now want to know what makes these tumours different, more aggressive and resistant to therapies," said Professor Gray.

When COVID closed down their lab in March, a team from the University of Essex turned to computational approaches to understand what makes some plants better adapted to transform light and carbon dioxide into yield through photosynthesis. They published their findings in the journal Frontiers of Plant Science.

There are two kinds of photosynthesis: C3 and C4. Most food crops depend on C3 photosynthesis where carbon is fixed into sugar inside cells called 'mesophyll' where oxygen is abundant. However, oxygen can hamper photosynthesis. C4 crops evolved specialized bundle sheath cells to concentrate carbon dioxide, which makes C4 photosynthesis as much as 60 percent more efficient.

In this study, scientists wanted to find out how C4 crops are able to express several important enzymes inside bundle sheath cells instead of the mesophyll.

"The ultimate goal is to be able to understand these mechanisms so that we can improve C3 photosynthesis in food crops like cowpea and cassava that smallholder farmers in sub-Saharan Africa depend on for their families' food and income," said Chidi Afamefule, a postdoctoral researcher working on Realizing Increased Photosynthetic Efficiency (RIPE) at Essex.

Led by the University of Illinois at the Carl R. Woese Institute for Genomic Biology, RIPE aims to boost food production by improving photosynthesis with support from the Bill & Melinda Gates Foundation, Foundation for Food and Agriculture Research, and U.K. Foreign, Commonwealth & Development Office. The RIPE project and its sponsors are committed to ensuring Global Access and making the project's technologies available to the farmers who need them the most.

The team compared the DNA of four C3 grass crops (including barley and rice) and four C4 grass crops (including corn and sorghum). Their goal was to identify regions of DNA that might control the expression of four enzymes involved in photosynthesis. This study is likely the first comparison of the expression of these enzymes (SBPase, FBPase, PRK, and GAPDH) in C3 and C4 crops.

"It would have been great to find a 'master regulator' that operates in all these enzymes, but we didn't find it, and we suspect it doesn't exist," said Afamefule, who led the study from his apartment during the pandemic.

Instead, they discovered C4 crops have several "activators" within their DNA that trigger expression in the bundle sheath and "repressors" that restrict expression in the mesophyll. They hope that they can use this genetic code to help less-efficient C3 crops photosynthesize better in the future.

"There are already efforts underway to help C3 crops operate more like C4 crops," said principal investigator Christine Raines, a professor in the School of Life Sciences at Essex where she also serves as the Pro-Vice-Chancellor for Research. "Studies like this help us identify small pieces within an incredibly complex machine that we have to understand before we can fine-tune and reengineer it."

The next step is to validate these findings in the lab. The team returned to their lab benches on July 6, 2020, adhering to all recommended safety guidelines from the School of Life Sciences at Essex.

Global stimulus plans for economic recovery after the pandemic could easily cover climate-friendly policies, suggests new study.

Governments worldwide are planning stimulus packages to boost the economy following the disruptions caused by the COVID-19 pandemic. So far, more than $12 trillion USD have been pledged in such packages. This response is three times larger than the 2008-2009 global financial crisis recovery spending, and represents around 15 percent of global gross domestic product (GDP).

A new analysis published today in Science, led by researchers from Imperial College London, Climate Analytics in Berlin, and the Electric Power Research Institute in the United States, shows that if just a tenth of this money was invested each year over the next five years in climate-positive recovery plans for the global energy system, the world could be put on track to meet the goals of the Paris Agreement.

The Paris Agreement aims to limit the average global temperature rise this century to well below 2°C above pre-industrial temperatures and to pursue efforts to keep it at 1.5°C. This will require a reduction in the use of fossil fuels, a shift to low-carbon renewable sources of energy, such as solar and wind power, and large improvements in energy efficiency.

However, current efforts by governments worldwide are insufficient to reach the Paris Agreement goals. Instead, today's policies are leading us towards a world 3°C above pre-industrial averages. These higher temperatures will bring greater risks and more severe impacts, such as droughts, flooding and storms.

The new analysis shows that an ambitious path to a 1.5°C world is well within reach if just a fraction of COVID-19 funding is invested in a 'climate-positive' recovery, with the dual aims of stimulating the global economy and accelerating the deployment of low-carbon energy supply and energy efficiency measures. This could be achieved, for example, via direct stimulus and investments as well as via supporting policies such as incentives and rebates.

Senior author Dr Joeri Rogelj, from the Grantham Institute - Climate Change and the Environment at Imperial, said: "Our findings show that investing in solutions to limit warming to 1.5°C is well within budget. In fact, the increase in low-carbon energy investments required over the next five years to move the world on track to meet the Paris Agreement targets is about eight times smaller than the total current COVID-19 stimulus."

First author Marina Andrijevic, from Climate Analytics and Humboldt University, said: "If just a fraction of this money was invested in climate-positive recovery plans, the world could achieve net zero carbon energy by mid-century. This is not about diverting money from COVID-19 stimulus or other low-carbon investments in industry, research and development, but providing for the win-win solution of a boosted economy that simultaneously helps our efforts to stall climate change."

Few countries have stated in full detail what they will use their recovery packages for, but immediate priorities will likely be to support healthcare systems, preserve livelihoods and stabilise employment. Beyond these, governments will be looking for investments that can foster economic recovery over the longer term.

Several reports, including a survey of over 230 experts worldwide, have shown how a green recovery can support this goal by providing both short- and long-term benefits, including job creation and lowering the investment risk of green technologies.

Dr Rogelj added: "Climate-positive recovery packages provide many benefits governments are looking for to get out of this crisis: they can boost employment and stimulate innovation, thus accelerating the development of technologies required for a global low-carbon transformation."

The team's analysis shows that a climate-positive recovery also needs a strong, near-term focus on actively avoiding a polluting recovery, such as stimulus packages that bail out fossil fuels. Investments in these sectors are poised to continue in the coming years, but there is strong evidence for redirecting this funding to a climate-positive recovery and for supporting the transition by other means, such as reskilling employees.

The analysis shows that this will be easier for some countries than others. The US and the European Union have pledged the most in post-pandemic recovery, and also need to invest the least proportionally in low-carbon energy to be on track to reach the Paris Agreement goals. Meanwhile, emerging economies like India have put forward less funding for pandemic recovery, but require proportionally more investments to provide their populations with reliable, clean and affordable energy.

Co-author Dr David McCollum, from the Electric Power Research Institute and the University of Tennessee, said: "The differing situations between developed and emerging economies in these times of crisis remind us of the need to look beyond borders and to collaborate internationally so that a climate-positive recovery benefits everyone, everywhere."

Boston, MA -- A new study examines whether the "race multiplier" correction factor for Black patients, used when estimating kidney function, may contribute to disparities in care for these patients with chronic kidney disease (CKD). Black patients with CKD have worse outcomes than other racial groups, including higher rates of anemia and hypertension, longer waits for referral to nephrology, and poorer access to transplantation. A research team led by investigators from Brigham and Women's Hospital in collaboration with investigators from Penn Medicine examined whether removing the race multiplier from calculations that estimate kidney function would change the way Black patients were classified. They found that up to one in every three Black patients would be reclassified as having a more severe stage of CKD, with one-quarter of Black patients going from stage 3 to stage 4 -- an important jump that could lead to more advanced kidney care and in some cases, key conversations about dialysis. Results of the study are published in The Journal of General Internal Medicine.

"Our findings suggest that using this racial correction can impact care for Black patients with advanced CKD and may delay important referrals and critical conversations," said senior author Mallika Mendu, MD, MBA, executive medical director of Clinical Operations at the Brigham. "Considering the inequities in kidney care and outcomes for Black patients, use of the eGFR race correction factor needs to be reconsidered."

In June, Mass General Brigham announced that it had eliminated use of race correction for kidney disease function, joining several leading institutions, including University of Washington and Vanderbilt University. But the use of race correction remains common at health systems throughout the country.

Physicians use estimated glomerular filtration rate (eGFR) as a convenient way to quickly assess kidney health or the stage of CKD. When a physician reviews a patient's eGFR in the medical record and identifies that patient as Black, they may receive an automatic prompt or notation to use a "race multiplier" when calculating eGFR. The race multiplier is based on studies conducted 10 to 20 years ago that concluded that Black patients had different levels of GFR than white patients -- without a clear biological explanation. The race multiplier is a number -- 1.159 -- that's meant to adjust values for Black patients to make them more equivalent to the value of other race groups.

To determine the impact of the race multiplier on the care of patients with advanced CKD, the investigators looked at the health records of more than 56,000 Mass General Brigham patients who had been seen before June 2019. Of those patients, 2,225 self-identified as African- American. The team then compared how their stage of CKD compared when the race multiplier was used and when it was eliminated. If the race multiplier had not been used, they found that 743 patients (33 percent) hypothetically, would have been reclassified as having a more severe CKD stage and 64 patients would have met criteria to be referred for kidney transplant evaluation. With the race multiplier in place, zero of those 64 patients had been referred, evaluated or waitlisted for kidney transplant.

"Race is a social, not a biologic construct, and the kidney function race multiplier ignores the substantial genetic diversity within self-identified Black patients," said co-author Thomas Sequist, MD, chief patient experience and equity officer for the Department of Quality and Patient Experience at Mass General Brigham. "Research studies have not provided an acceptable scientific rationale for making clinical decisions based on the social construct of race."

The authors note that their study was conducted at a single health care system with a relatively small proportion of Black patients, and additional studies in other health care systems are needed.

"Our hope is that this work will inspire others to conduct their own investigations about the race multiplier and its effect in more diverse settings," said Mendu. "The risk of underdiagnosis and delays in care for Black patients is critical -- and given a history of poor clinical outcomes in this patient population, it is imperative that we do all we can to mitigate and ultimately eliminate disparities in patient care."

UNIVERSITY PARK, Pa. -- RADAR satellites can collect massive amounts of remote sensing data that can detect ground movements -- surface deformations -- at volcanoes in near real time. These ground movements could signal impending volcanic activity and unrest; however, clouds and other atmospheric and instrumental disturbances can introduce significant errors in those ground movement measurements.

Now, Penn State researchers have used artificial intelligence (AI) to clear up that noise, drastically facilitating and improving near real-time observation of volcanic movements and the detection of volcanic activity and unrest.

"The shape of volcanoes is constantly changing and much of that change is due to underground magma movements in the magma plumbing system made of magma reservoirs and conduits," said Christelle Wauthier, associate professor of geosciences and Institute for Data and Computational Sciences (ICDS) faculty fellow. "Much of this movement is subtle and cannot be picked up by the naked eye."

Geoscientists have used several methods to measure the ground changes around volcanoes and other areas of seismic activity, but all have limitations, said Jian Sun, lead author of the paper and a postdoctoral scholar in geosciences, funded by Dean's Postdoc-Facilitated Innovation through Collaboration Award from the College of Earth and Mineral Sciences.

He added that, for example, scientists can use ground stations, such as GPS or tiltmeters, to monitor possible ground movement due to volcanic activity. However, there are a few problems with these ground-based methods. First, the instruments can be expensive and need to be installed and maintained on site.

"So, it's hard to put a lot of ground-based stations in a specific area in the first place, but, let's say there actually is a volcanic explosion or an earthquake, that would probably damage a lot of these very expensive instruments," said Sun. "Second, those instruments will only give you ground movement measurements at specific locations where they are installed, therefore those measurements will have a very limited spatial coverage."

On the other hand, satellites and other forms of remote sensing can gather a lot of important data about volcanic activity for geoscientists. These devices are also, for the most part, out of harm's way from an eruption and the satellite images offer very extended spatial coverage of ground movement. However, even this method has its drawbacks, according to Sun.

"We can monitor the movement of the ground caused by earthquakes or volcanoes using RADAR remote sensors, but while we have access to a lot of remote sensing data, the RADAR waves must go through the atmosphere to get recorded at the sensor," he said. "And the propagation path will likely be affected by that atmosphere, especially if the climate is tropical with a lot of water vapor and clouds variations in time and space."

According to the researchers, who report their findings in a recent issue of the Journal of Geophysical Research, a deep learning method they developed acts much like a jigsaw puzzle master. By taking pieces of data that are clear, the system can begin to fill in the holes of "noisy" data, holes created by the interference of weather and other instrumental noises. It can then build a reasonably accurate picture of the land and its movements.

Using this deep learning method, scientists could gain valuable insights into the movement of the ground, particularly in areas with active volcanoes or earthquake zones and faults, said Sun. The program may be able spot potential warning signs, such as sudden land shifts that might be a portent of an oncoming volcanic eruption, or earthquake.

"It's really important for areas close to active volcanoes, or near where there have been earthquakes, to have as early warning as possible that something might happen," said Sun.

Deep learning, as its name suggests, uses training data to teach the system to recognize features that the programmers want to study. In this case, the researchers trained the system with synthetic data that was similar to satellite surface deformation data. The data included signals of volcanic deformation, both spatially and topographically correlated atmospheric features and errors in the estimation of satellite orbits.

Future research will focus on refining and expanding our deep learning algorithm, according to Wauthier.

"We wish to be able to identify earthquake and fault movements as well as magmatic sources and include several underground sources generating surface deformation," she said. "We will apply this new groundbreaking method to other active volcanoes thanks to support from NASA."

WEST LAFAYETTE, Ind. -- A rectangular robot as tiny as a few human hairs can travel throughout a colon by doing back flips, Purdue University engineers have demonstrated in live animal models.

Why the back flips? Because the goal is to use these robots to transport drugs in humans, whose colons and other organs have rough terrain. Side flips work, too.

Why a back-flipping robot to transport drugs? Getting a drug directly to its target site could remove side effects, such as hair loss or stomach bleeding, that the drug may otherwise cause by interacting with other organs along the way.

The study, published in the journal Micromachines, is the first demonstration of a microrobot tumbling through a biological system in vivo. Since it is too small to carry a battery, the microrobot is powered and wirelessly controlled from the outside by a magnetic field.

"When we apply a rotating external magnetic field to these robots, they rotate just like a car tire would to go over rough terrain," said David Cappelleri, a Purdue associate professor of mechanical engineering. "The magnetic field also safely penetrates different types of mediums, which is important for using these robots in the human body."

The researchers chose the colon for in vivo experiments because it has an easy point of entry - and it's very messy.

"Moving a robot around the colon is like using the people-walker at an airport to get to a terminal faster. Not only is the floor moving, but also the people around you," said Luis Solorio, an assistant professor in Purdue's Weldon School of Biomedical Engineering.

"In the colon, you have all these fluids and materials that are following along the path, but the robot is moving in the opposite direction. It's just not an easy voyage."

But this magnetic microrobot can successfully tumble throughout the colon despite these rough conditions, the researchers' experiments showed. A video explaining the work is available on YouTube at https://youtu.be/9OsYpJFWnN8.

The team conducted the in vivo experiments in the colons of live mice under anesthesia, inserting the microrobot in a saline solution through the rectum. They used ultrasound equipment to observe in real time how well the microrobot moved around.

The microrobots could also tumble in colons excised from pigs, the researchers found, which have similar guts to humans.

"Moving up to large animals or humans may require dozens of robots, but that also means you can target multiple sites with multiple drug payloads," said Craig Goergen, Purdue's Leslie A. Geddes Associate Professor of Biomedical Engineering, whose research group led work on imaging the microrobot through various kinds of tissue.

Solorio's lab tested the microrobot's ability to carry and release a drug payload in a vial of saline. The researchers coated the microrobot with a fluorescent mock drug, which the microrobot successfully carried throughout the solution in a tumbling motion before the payload slowly diffused from its body an hour later.

"We were able to get a nice, controlled release of the drug payload. This means that we could potentially steer the microrobot to a location in the body, leave it there, and then allow the drug to slowly come out. And because the microrobot has a polymer coating, the drug wouldn't fall off before reaching a target location," Solorio said.

The magnetic microrobots, cheaply made of polymer and metal, are nontoxic and biocompatible, the study showed. Cappelleri's research group designed and built each of these robots using facilities at the Birck Nanotechnology Center in Purdue's Discovery Park.

Commonly-used roll-to-roll manufacturing machinery could potentially produce hundreds of these microrobots at once, Cappelleri said.

The researchers believe that the microrobots could act as diagnostic tools in addition to drug delivery vehicles.

"From a diagnostic perspective, these microrobots might prevent the need for minimally invasive colonoscopies by helping to collect tissue. Or they could deliver payloads without having to do the prep work that's needed for traditional colonoscopies," Goergen said.

When southern Rocky Mountain forests are viewed from a distance these days, it may not look like much is left. Large swaths of dead, standing Engelmann spruce trees tell the tale of a severe regional spruce beetle epidemic in its waning stages. But among those dead trees, researchers have found good news. Zoom-in to the ground cover of these forests and there is life, even more abundant because of this disturbance.

New research led by Colorado State University and published online in Scientific Reports suggests that spruce beetle outbreaks may help create habitat for pollinator communities in wilderness settings. The research team found significant increases in floral abundance and wild bee diversity in outbreak-affected forests, compared to similar, undisturbed forest. Lead author Seth Davis said it may seem counterintuitive that landscape-level damage by one type of insect could still benefit another.

"Disturbances from bark beetles are typically regarded as undesirable for ecosystem function and human use," said Davis, an assistant professor in the Forest and Rangeland Stewardship department. "But there is conservation value in post-outbreak forests; they appear to be the areas supporting more robust bee populations."

This is good news for wild bee communities, which have been declining in recent years. The different bee species identified in this high-elevation study are made for harsh, cold environments. The fact that a natural disturbance can boost their presence is a boon to these rare, endemic creatures not found in warmer habitats. It's also a benefit for these forests, because wild bees perform essential pollination services in ecosystems with very short growing seasons.

A serendipitous observation

Davis regularly works in high-elevation forests. A few years ago, during another research project with department colleagues, he noticed a correlation between the number and diversity of bees observed, and the structure of the forest. He has since opened up this new thread of bee diversity research by combining it with his training in bark beetles.

"Disturbance studies on bees have primarily focused on fire," said Davis. "There hasn't been a lot of research looking at bee responses to beetle outbreaks."

For this new study, his team developed a natural experiment, collecting parallel data in 28 beetle-affected and undisturbed alpine sites in north-central Colorado. They collected bees for two years at three different times across each growing season, and also recorded standard tree measurements and understory, or ground cover, plant data at the collection sites.

The team found that average floral abundance in spruce beetle-affected stands was 67 percent higher than in non-affected stands. The average number of bee species was also 37 percent greater in beetle-affected stands, with more species present in June than later in the growing season. Davis said the relationship between these insects and their surrounding vegetation may be more complex.

"It appears there are different controls over bee abundance and diversity," Davis said. "Bee abundance was correlated to the floral species, while the diversity is more related to the forest structure, both of which are affected by bark beetles."

In other words, bark beetles directly changed the forest structure which indirectly improved wild bee populations by providing a more robust food source for the buzzing insects on the ground.

Spruce beetle-affected forests offer a few advantages for understory plants and wild bees. Tree mortality typically opens up the forest canopy, allowing more light to reach plants and flowers on the forest floor. Dead trees also remain standing for up to 25 years after this disturbance. This offers more cavities for wild bees that nest in trees and dead wood.

Davis said he is interested in exploring this topic further to better understand these relationships over a longer time period and at a larger scale. As forests recover from outbreaks, he would like to see how long this benefit lasts. There is also the size disparity between small bee populations in one locale and the regional magnitude of these disturbances. It will be important to understand how well one small spot predicts these results at the landscape level.

While bees were captured for the purposes of this study, previous research has shown that the bee capture methods employed do not affect the overall bee community.

LOWELL, Mass. - Former Vice President Joe Biden has a 10-point lead over President Donald Trump in the contest for the White House in a new national poll of likely voters released today by the UMass Lowell Center for Public Opinion.

Including the minor party candidates on the ballot, Biden leads with 53 percent of likely voters, Trump has 43 percent, other candidates are at 2 percent and only 3 percent of likely voters say they are still undecided, according to the independent, nonpartisan poll.

The relatively low number of undecided voters is underscored by the fact that 16 percent of likely voters have already voted. Just over two-thirds of voters said they plan to eschew their traditional Election Day polling place in 2020 and either vote by mail (45 percent) or vote early in person (22 percent).

"Biden's double-digit lead signals that the president's hopes of re-election are dwindling, with less than three weeks until Election Day and many voters already voting early and by mail," said Joshua Dyck, director of the Center for Public Opinion and associate professor of political science.

Biden leads Trump among voters with a college degree, 62 percent to 36 percent. Among those without a bachelor's degree, Biden leads 49 percent to Trump's 46 percent. However, among white respondents without a degree, Trump leads Biden 61 percent to 36 percent, while Biden leads Trump among whites with a college degree 60 percent to 38 percent.

The gender gap revealed in this poll is on par with historic averages from the 2012 and 2016 elections in the difference between male and female voters' support for Democratic candidates. In this poll, Biden does about 10 points better among women than men, leading 57 percent to 38 percent among women who are likely voters and 49 percent to 48 percent among men likely voters.

While Trump trails Biden by double digits nationally, his approval rating has not undergone a precipitous decline, which has hovered between an average of 40 and 45 percent nationally for most of the last three years. Overall, 44 percent of likely voters approve of the way Trump is handling his job as president and 56 percent disapprove. But nearly half of the electorate (47 percent of likely voters) say they strongly disapprove of the way the president has handled his job.

Because there's no corresponding job approval rating for Biden, the point of comparison for the candidates is favorability rating. In 2016, both candidates - Trump and former Secretary of State Hillary Clinton -
had net negative approval ratings in polling averages heading into the election. In 2020, the pattern is different: Trump continues to have a net negative favorability rating of -13; 42 percent find him favorable, 55 percent unfavorable and 3 percent have no opinion. Biden, however, is net positive +9; 50 percent find him favorable, 41 percent unfavorable and 9 percent have no opinion. Clinton is still net negative at -17 (35 percent favorable, 52 percent unfavorable, 12 percent no opinion), which indicates that Democrats have a much more popular nominee in 2020.

With Trump's coronavirus-positive diagnosis on Oct. 2, the campaign became fully focused once again on the president's handling of COVID-19. Overall, a majority of likely voters polled (57 percent) are not satisfied with the way the federal government has handled the pandemic, compared to 43 percent who said they are satisfied. This stands in stark contrast to state governments that get much higher marks: 59 percent of Americans said they are satisfied with their state government's response compared to 41 percent who said they are unsatisfied.

Asked who they trust more to handle COVID-19, 52 percent of likely voters say Biden compared to 36 percent of likely voters who said Trump. On the question of whether Trump could have avoided contracting COVID-19 by wearing a mask more often, 71 percent of likely voters said yes while 29 percent said no.

"With the total American dead from the virus approaching a quarter-million by Election Day, voters are frustrated by Trump's response to the virus, both personally and as president. Unfortunately for the president, there's no miracle cure for his dismal poll numbers on the pandemic," said John Cluverius, associate director of the Center for Public Opinion and assistant professor of political science.

The poll of likely voters also found:

With Supreme Court hearings taking place this week, nominee Amy Coney Barrett has a -1 net negative favorability rating among likely voters - 31 percent favorable, 32 percent unfavorable, 25 percent no opinion and 12 percent never heard of her.

Asked who they think will win the 2020 presidential election, likely voters gave Biden the edge: 45 percent said Biden will win and 41 percent said Trump will win.

Asked about a hypothetical alternative matchup, Biden leads Pence 54 percent to 41 percent with 4 percent undecided. Harris leads Pence 50 percent to 43 percent with 6 percent undecided.

Just 30 percent of Americans think things are headed in the right direction, while 70 percent say things are on the wrong track.

On Trump's signature issue, the economy, 47 percent said Biden is better suited to handle the economy, compared to 42 percent who said Trump.

On who best represents American values, Biden leads Trump 48 percent to 37 percent. Biden also leads Trump on who is a more devout Christian, 39 percent to 29 percent. Asked who is more of a good man, 50 percent said Biden compared to 31 percent who said Trump.

More respondents said Biden would be better suited to handle race relations, 49 percent to 34 percent for Trump and more feel Biden is more honest and trustworthy, 49 percent to 32 percent for Trump.

On who will better handle America's reputation abroad, Biden leads 51 percent to 37 percent for Trump. On who is better suited to handle police reform, 46 percent said Biden and 38 percent said Trump. Fifty-one percent said Biden is more suited to handling health care compared to 35 percent who said Trump.

Trump leads Biden on only two metrics on which respondents were polled: who is more of a bully (67 percent said Trump vs. 16 percent who said Biden) and who is more corrupt (50 percent said Trump compared to 34 percent who said Biden).