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Remote 24-hour monitoring for cancer patients receiving chemotherapy helps to better manage side effects and improve quality of life, finds a study published by The BMJ today.

The researchers say remote monitoring can provide a safe, secure, and "real time" system that optimises symptom management and supports patients to remain at home - and is particularly relevant in the context of the covid-19 pandemic.

Effective symptom monitoring and management is essential during chemotherapy for cancer, but current approaches rely on patients recognising that symptoms are severe enough to warrant reporting to their care team.

Previous research on remote monitoring during chemotherapy has shown benefits, but is largely based on short trials from a single site or country, making it difficult to draw wider conclusions.

To address this evidence gap, a team of international researchers set out to evaluate the effects of remote monitoring of chemotherapy related side effects on symptom burden, supportive care needs, anxiety, work limitations, and quality of life.

Their findings are based on 829 patients aged 18 years or older, diagnosed with breast cancer, colorectal cancer, Hodgkin's disease, or non-Hodgkin's lymphoma, and receiving chemotherapy at 12 cancer centres in Austria, Greece, Norway, the Republic of Ireland and the UK.

Patients were randomly allocated to 24-hour symptom monitoring via the Advanced Symptom Management System (ASyMS) (intervention group) or standard care at their cancer centre (control group) over six cycles of chemotherapy.

Intervention patients completed a daily symptom questionnaire on a handheld ASyMS device; this generated alerts to hospital clinicians if action was needed. Patients were also provided with self-care advice with information on how to manage their symptoms themselves.

The researchers found that for the intervention group, symptom burden remained at pre-chemotherapy treatment levels, whereas controls reported an increase from cycle 1 onwards.

Analysis indicated significant reductions in favour of ASyMS for psychological and physical symptoms and for level of distress associated with each symptom.

Health related quality of life scores were higher in the intervention group across all cycles, whereas average scores for anxiety were lower.

Measures of cancer patients' confidence and ability to engage in their care were also higher in the intervention group, and most supportive care needs were lower, including sexual related needs and physical and daily living needs.

Other areas of supportive care needs and work limitations were similar in both groups, and the safety of ASyMS was satisfactory.

This is the largest trial to date of remote monitoring of symptoms during chemotherapy for cancers being treated with curative intent, and its robust design avoided many limitations of previous studies, say the researchers.

They acknowledge some limitations, including technical problems and the fact that most participants had breast cancer and were female, suggesting a larger study is warranted for patients with other types of cancer.

Nevertheless, they say their findings suggest that an evidence based remote monitoring intervention, such as ASyMS, has potential for implementation into routine care to make a meaningful difference to people with cancer.

Remote monitoring systems will be vital for future services, particularly with blended models of care delivery arising from the covid-19 pandemic, they add.

Alexandria, Va., USA - Parach Sirivichayakul, Mahidol University, Bangkok, Thailand, presented the poster "Preventing Approximal Caries in Primary Teeth With Topical Fluorides" at the virtual 99th General Session & Exhibition of the International Association for Dental Research (IADR), held in conjunction with the 50th Annual Meeting of the American Association for Dental Research (AADR) and the 45th Annual Meeting of the Canadian Association for Dental Research (CADR), on July 21-24, 2021.

There is limited evidence regarding the use of silver diamine fluoride (SDF) for caries prevention in primary teeth. This randomized clinical trial evaluated the effectiveness of 38% SDF, 5% sodium fluoride (NaF) varnish and placebo control in preventing approximal caries in primary teeth.

Children aged 4-6 years who had at least one sound approximal surface at the distal surface of canines or the mesial or distal surface of the first and second molars assessed from bitewing radiographs were recruited. The participants were randomly allocated into three intervention groups as follows: Group 1 = control (water) , Group 2 = 5% NaF varnish (Duraphat) and Group 3 = 38% SDF (Topamine). All agents were applied semi-annually and the new caries development was assessed by the bitewing radiographic examinations at 6-, 12-, and 18-month follow-ups by two blind calibrated investigators.

The new approximal caries development rates of Group 1, 2, and 3 at the 18-month examination were 22.5%, 13.6%, and 24.3%, respectively (p

View this poster presentation in the IADR General Session Virtual Experience Platform.

In the United States, climate change is controversial, which makes communicating about the subject a tricky proposition.

A recent study by Portland State researchers Brianne Suldovsky, assistant professor of communication, and Daniel Taylor-Rodriguez, assistant professor of statistics, explored how liberals and conservatives in Oregon think about climate science to get a better sense for what communication strategies might be most effective at reaching people with different political ideologies. The study was published in Climatic Change in June.

Prior studies have shown that exposing climate change skeptics, who are more likely to be conservatives, to more science is unlikely to change the way they think about the issue. Instead, Suldovsky and Taylor-Rodriguez found that a more fruitful strategy may be to give conservatives opportunities to share their own lived experiences with the effects of climate change.

To learn more about how liberals and conservatives differ in how they think about climate change, Suldovksy and Taylor-Rodriguez created an online survey that was completed by 1,049 Oregonians. The participants ranged from age 18 to 86 and closely mirrored the demographics of the state in terms of sex, race, age and education. There was also ample representation from different political groups; 43% of participants were moderates, 30% were liberals and 27% were conservatives.

The survey asked participants questions about how they thought about climate change, and included questions about how certain they were that climate change is happening; how complicated or complex they think climate science is; and who they rely on to give them knowledge about climate change -- their own direct lived experience or experts. The survey also measured how participants prefer to engage with climate science. The researchers then used a statistical tool called multivariate regression to figure out what factors predicted engagement preferences.

"The most interesting thing to me is that liberals and conservatives are just seeing climate science from a completely different epistemic vantage point," says Suldovsky about the results.

The survey showed that liberals see climate science and climate change as certain and simple. They don't think it's very complicated to understand, and they also don't think it's going to be refuted in the future. Liberals also defer to scientific experts about climate change to such an extent that they reported that they would defer to what a scientist says about climate change even if it contradicts their own experience.

"That's a pretty bold thing to agree with," says Suldovsky. "That was pretty shocking to me."

By contrast, conservatives saw climate science completely differently. "They see it as far less certain and far more complex, [the latter] is super interesting because in that way conservatives are more in line with climate scientists," says Suldovsky. Conservatives also rely more on their own direct lived experience to give them knowledge about the world and knowledge about climate change.

"That has huge implications for the way that we engage with conservatives because, up until this point, the approach has been to shove more information from climate scientists at them and that'll do the trick, and it doesn't," says Suldovsky. "One of the things that our study is showing is that [resistance] might be because conservatives are looking to a different source to give them knowledge about climate change: their own direct lived experience."

The results also showed that people who believe that climate change is certain and simple--like liberals tend to--prefer receiving more information from experts. This one-way knowledge transfer is also called the deficit model of science communication and has been the standard communication strategy. By contrast, people who rely on their own experience and see climate change as complicated and fairly uncertain--like conservatives tend to--prefer what is called a lay expertise model of engagement. This means they value being able to contribute their own knowledge and experience to help better understand climate change.

These findings suggest that people who communicate about climate change may benefit from a shift of perspective.

"Attending to people's philosophical beliefs might get us beyond this place where we focus on the facts," says Suldovsky. "This study demonstrates we can go deeper than that and ask questions and measure how people are seeing the world. That might get us a little bit further."

Suldovsky herself changed her views on climate change, in part thanks to philosophy.

"I grew up very conservative. I grew up in northern Idaho. I grew up very religious. I didn't accept evolution. I didn't accept climate science and so I know what it feels like to feel like science is your adversary," she says. "And what changed my mind was philosophy, learning that there are different ways to think about the world and different ways to think about knowledge."

Instead of presenting science as the only answer, Suldovsky suggests it could be presented as a piece of the puzzle that is combined with other perspectives and ways of knowing that fill in the rest of the puzzle. An example of this approach could involve asking fishermen, farmers and ranchers what changes they have noticed over the past few decades.

Focusing on the effects of climate change might help get buy-in for mitigation strategies from people of different political ideologies. Take dealing with rising sea levels or heat waves, for example. "Sea level rise is something that we can infrastructurally deal with without people agreeing on why that sea level rise is occuring," says Suldovsky. "Cities can plan for increased heat waves without convincing people that climate change is causing the heat waves."

The results of this study also suggest that climate science--and other controversial scientific topics such as GMOs and vaccines--could benefit from an expanded understanding of science communication.

"Just broadening our conception of what communication and engagement can look like to include things like public forums or transdisciplinary science where you're involving multiple perspectives and problem solving would be helpful," says Suldovsky.

Suldovsky and Taylor-Rodriguez are now following up this study by looking at the relationship between extreme weather perceptions, the actual weather and climate change beliefs.

Since buildings consume 75% of electricity in the U.S., they offer great potential for saving energy and reducing the demands on our rapidly changing electric grid. But how much, where, and through which strategies could better management of building energy use actually impact the electricity system?

A comprehensive new study led by researchers from the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) answers these questions, quantifying what can be done to make buildings more energy efficient and flexible in granular detail by both time (including time of day and year) and space (looking at regions across the U.S.). The research team, which also included scientists from the National Renewable Energy Laboratory (NREL), found that maximizing the deployment of building demand management technologies could avoid the need for up to one-third of coal- or gas-fired power generation and would mean that at least half of all such power plants that are expected to be brought online between now and 2050 would not need to be built.

Their findings were published recently in the journal Joule.

"A key reason why we don't hear more about the role of our buildings as a significant resource for the clean energy transition is because it's been challenging to quantify that resource at a large scale - and without hard numbers at scale, it's hard for policy makers or grid operators to plan around it," said Berkeley Lab researcher Jared Langevin, lead author of the study. "Our overarching belief here was that producing these kinds of estimates that make the role of these demand-side building technologies more concrete will help ensure that we do more to encourage the deployment of those technologies alongside the deployment of renewable generation and batteries."

"We're excited to collaborate with Berkeley Lab on these research findings, which emphasize the impact of our nation's buildings to achieve a decarbonized energy system," said Achilles Karagiozis, director of NREL's Building Technologies and Science Center.

The so-called demand-side of electricity is electricity that is used in homes and workplaces, such as for air-conditioning, water heating, and powering lights and appliances. The researchers approached this electricity use from buildings as a grid resource; by increasing the efficiency and flexibility of buildings' electricity use, such as by operating higher-performing equipment and shifting the time when its usage takes place, they found this resource to be substantial, avoiding up to 742 terawatt-hours (TWh) of annual electricity use and 181 gigawatts (GW) of daily net peak load in 2030, rising to 800 TWh and 208 GW by 2050. (Total U.S. electricity consumption in 2020 was about 3,800 TWh.)

The researchers found that the most impactful measures for residential buildings were preconditioning (where homes are precooled so as to reduce air conditioning usage at peak times) and using heat pump water heaters; for commercial buildings, plug load management, where software is used to manage the electricity use of computers and other electronic devices in a building, was most impactful.

"Our initial estimates suggest tens of billions of dollars in annual cost savings potential for grid operators - not to mention the potential energy cost savings for families and businesses," said Karagiozis. "Buildings are also a significant source of flexibility for grid operators, primarily in dialing down electricity demand during times when it would normally be at its peak, such as during really hot summer days when most air conditioners are running."

By reducing this peak demand, Langevin said utilities may have lower need for battery technologies as they deploy more renewable energy. "Indeed, the flexible resource we found is comparable to higher-end projections of battery deployment needs under higher renewable energy deployment," he said.

The regions where buildings proved to offer the largest grid resource were in Texas and the Southeast of the U.S., as well as the Great Lakes and Mid-Atlantic regions. "These are areas with high population, strong space conditioning needs, and lots of electric equipment already installed," Langevin said. "This information at the regional scale is really important for developing tangible policies for realizing the resource that we're reporting."

Strategies for capturing the potential building-grid resource that the study identifies are already under development. Recently, for example, DOE released a National Roadmap for Grid-Interactive Efficient Buildings (https://gebroadmap.lbl.gov/), which draws from the study's outcomes and provides concrete recommendations for how to triple the efficiency and flexibility of the buildings sector by 2030.

"Continued efforts along these lines will be critical for establishing a key role for the buildings sector in the future evolution of the U.S. electricity system," said Langevin. "Our findings are encouraging, but now we need to find ways of quickly putting this resource into practice."

Aryl sulfide, an aromatic compound in which sulfur is attached to an aryl (a functional group derived from an aromatic ring), is found in biologically active materials effective against asthma, Alzheimer's disease, and cancer. As a result, chemists have shown a lot of interest in synthesizing aryl sulfides. Traditionally, carbon-sulfur (C-S) bond formation reactions between thiols and aryl electrophiles catalyzed by transition metals have been employed for aryl sulfide synthesis because of their high reliability. However, thiols have an unpleasant smell and are toxic. Could there be a way to synthesize aryl sulfides that avoids the use of thiols?

A team of chemists from Waseda University, Japan, led by Professor Junichiro Yamaguchi addresses this question in a recent study published in the Journal of the American Chemical Society, and has come up with a technique that gets the job done without thiols. The team took the hint from a previous study where they used a nickel catalyst to synthesize aromatic esters from two aromatic compounds. "In 2020, we developed the first ester synthesis method using aromatic ring exchange reactions and decided to apply the knowledge gained from this reaction to realize a thiol-free sulfide synthesis," explains Yamaguchi, speaking of the origin of the study.

Against this backdrop, the team set out to synthesize aryl sulfides and aromatic esters. They started out by reacting 4-tolyl sulfide and 4-phenylbenzoate in presence of a nickel catalyst and found that the desired aryl sulfide was synthesized in the presence of a ligand, dcypt, and a zinc additive, Zn(OAc)2.

Encouraged by the results, the team moved on to investigate the mechanism of the reaction. They reacted the aryl sulfide with the nickel catalyst (Ni(cod)2) and the ligand, dcypt, and observed the formation of a nickel complex consisting of the catalyst, the ligand, and the aryl sulfide. This nickel complex could react with the aromatic ester to form a pair of nickel complexes which could react with each other to form the desired aryl sulfide.

From these reactions, the team concluded that the Ni-catalyzed aryl sulfide synthesis occurred in a sequence of steps. Initially, the aryl sulfide and aromatic esters underwent simultaneous oxidative addition reactions to the nickel/ligand catalyst forming nickel complexes. These nickel complexes could engage in an aryl exchange reaction to form a set of nickel intermediates. This was then followed by the reductive elimination of the intermediates to regenerate the Ni/ligand catalyst and form the desired aryl sulfide.

The reductive elimination of the nickel intermediates, however, reduced the yield of the aryl sulfide. To combat this, the team employed 2-pyridyl sulfide, which accelerated this limiting step, improving the yield. Additionally, the synthesis method worked with several aryl electrophiles such as aromatic esters, arenol derivatives and aryl halides.

"The sulfide synthesis method developed can proceed for a variety of complex bioactive compounds such as probenecid, flavone, estrone, phenylalanine, umbelliferone, and β-isocupreidine derivatives," comments an excited Yamaguchi, contemplating the prospects of their novel synthesis technique. "Furthermore, the ability to use environmentally friendly aromatic esters and phenol derivatives as feedstock and pyridyl sulfide as a sulfide agent could make this technology suitable for both laboratory and industrial-scale applications."

Nanomaterials have been used in a variety of emerging applications, such as in targeted pharmaceuticals or to bolster other materials and products such as sensors and energy harvesting and storage devices. A team in the McKelvey School of Engineering at Washington University in St. Louis is using nanoparticles as heaters to manipulate the electrical activity of neurons in the brain and of cardiomyocytes in the heart.

The findings, published July 3, 2021, in Advanced Materials, have the potential to be translated to other types of excitable cells and serve as a valuable tool in nano-neuroengineering.

Srikanth Singamaneni, a materials scientist, and Barani Raman, a biomedical engineer, and their teams collaborated to develop a noninvasive technology that inhibits the electrical activity of neurons using polydopamine (PDA) nanoparticles and near-infrared light. The negatively charged PDA nanoparticles, which selectively bind to neurons, absorb near-infrared light that creates heat, which is then transferred to the neurons, inhibiting their electrical activity.

"We showed we can inhibit the activity of these neurons and stop their firing, not just on and off, but in a graded manner," said Singamaneni, the Lilyan & E. Lisle Hughes Professor in the Department of Mechanical Engineering & Materials Science. "By controlling the light intensity, we can control the electrical activity of the neurons. Once we stopped the light, we can completely bring them back again without any damage."

In addition to their ability to efficiently convert light into heat, the PDA nanoparticles are highly biocompatible and biodegradable. The nanoparticles eventually degrade, making them a convenient tool for use in in vitro and in vivo experiments in the future.

"When you pour cream into hot coffee, it dissolves and becomes creamed coffee through the process of diffusion," he explained. "It is similar to the process that controls which ions flow in and out of the neurons. Diffusion depends on temperature, so if you have a good handle on the heat, you control the rate of diffusion close to the neurons. This would in turn impact the electrical activity of the cell. This study demonstrates the concept that the photothermal effect, converting light into heat, near the vicinity of nanoparticles tagged neurons can be used as a way to control specific neurons remotely."

To continue the coffee analogy, the team has designed a photothermal foam that is similar to a sugar cube, forming a dense population of nanoparticles in tight packaging that acts more quickly than individual sugar crystals that disperse, Raman said.

"With so many of them packed in a small volume, the foam is quicker in transducing light to heat and give more efficient control to only the neurons we want," he said. "You don't have to use high-intensity power to generate the same effect."

In addition, the team, which includes Jon Silva, associate professor of biomedical engineering, applied the PDA nanoparticles to cardiomyocytes, or heart muscle cells. Interestingly, the photothermal process excited the cardiomyocytes, showing that the process can increase or decrease the excitability in cells depending on their type.

"The excitability of a cell or tissue, whether it be cardiomyocytes or muscle cells, depends to a certain extent on diffusion," Raman said. "While cardiomyocytes have a different set of rules, the principle that controls the sensitivity to temperature can be expected to be similar."

Now, the team is looking at how different types of neurons respond to the stimulation process. They will be targeting particular neurons by selectively binding the nanoparticles to provide more selective control.

The tiny organisms living in soil may have a greater effect on the yield and pest and disease resistance of crop plants grown in that soil than previously known.

Researchers at North Carolina State University and the University of Kansas have shown that soil microbes - microscopic organisms like viruses, bacteria and fungi found throughout nature - play a role in the phenomenon of heterosis or "hybrid vigor," the superior performance of crossed plant lines, or hybrids, over inbred plant lines. Hybrids are often used by farmers for agricultural production due their superior crop yields.

Research into hybrid vigor has generally highlighted the roles of genetic and abiotic environmental factors behind the phenomenon. So finding that the biotic soil environment impacts heterosis was a bit surprising and serendipitous, the researchers say.

"This work moves us toward a better understanding of what's driving heterosis," said Manuel Kleiner, an assistant professor of plant and microbial biology at NC State and a co-corresponding author of a paper describing the research. "Microbes are critical players in causing effects on corn plants - it's not just temperature and soil type."

The researchers experimented with two types of inbred corn plants and a hybrid of those two lines in laboratory and field tests in North Carolina and Kansas.

The researchers started by growing hybrid and inbred corn plants in sterile bags; both types of plants grew similarly sized roots and shoots inside the bags. But when the researchers added to the bags a controlled set of microbes known to associate with corn roots in nature, hybrid lines grew more than inbred lines - their roots and shoots weighed more - showing the expected effects of heterosis.

"This seemed to be the result of a negative microbial effect on inbred lines, rather than a helping effect on hybrids," Kleiner said.

Similar heterosis-enhancing activity of microbes was observed in field tests in North Carolina in which hybrid and inbred lines were grown in untreated plots, plots treated with an antimicrobial chemical, and in plots treated with both the antimicrobial chemical and a method of "cooking" the soil by sending ultra-hot steam into it.

Surprisingly, when a similar experiment was performed in Kansas, the opposite effect was observed - treatments that reduced the microbial populations in the soil caused increased heterosis.

"We can now say that microbes will have effects on heterosis, but we can't predict the direction of those effects," Kleiner said.

"We know that microbes are affecting inbreds and hybrids of corn in different ways, but the effects may depend on the environment or on the particular microbes in the soil," said Peter Balint-Kurti, USDA professor of plant pathology at NC State and a paper co-author.

The researchers plan to continue their work studying the effects of microbes on corn heterosis.

No one wants bad breath -- not when visiting friends and family, at a job interview, and especially not on a first date. Smelly breath can make things awkward, but it also is a natural warning sign, indicating that serious dental issues are occurring. Now, researchers reporting in ACS Nano have constructed a portable, thumb-sized device that diagnoses bad breath by quickly "sniffing" exhalations for the gas that makes it stinky -- hydrogen sulfide.

Because most people can't smell their own breath, they need to ask someone else, which can be embarrassing and awkward. Some devices measure small amounts of stinky hydrogen sulfide, but they require exhaled air to be collected and tested on expensive instruments in a lab, which is not feasible for consumers. Previous studies have shown that when some metal oxides react with sulfur-containing gases, their electrical conductivity changes. And when metal oxides are paired with noble metal catalysts, they can become more sensitive and selective. So, to develop a small, real-time bad-breath analyzer, Kak Namkoong, Il-Doo Kim and colleagues wanted to find the right combination of substances that would elicit the fastest and strongest response to hydrogen sulfide in air blown directly onto it.

The researchers mixed sodium chloride (an alkali metal salt) and platinum (a noble metal catalyst) nanoparticles with tungsten, and electrospun the solution into nanofibers that they heated, converting the tungsten into its metal oxide form. In preliminary tests, the composite made from equal parts of each metal had the largest reactivity to hydrogen sulfide, which the team measured as a large decrease in electrical resistance in less than 30 seconds. Although this nanofiber reacted with a few sulfur-containing gases, it was most sensitive to hydrogen sulfide, creating a response 9.5 and 2.7 times greater than with dimethyl sulfide or methyl mercaptan, respectively. Finally, the team coated interdigitated gold electrodes with the nanofibers and combined the gas sensor with humidity, temperature and pressure sensors into a small prototype device that was about the size of a human thumb. The device correctly identified bad breath 86% of the time when real breaths from people were exhaled directly onto it. The researchers say that their sensor could be incorporated into very small devices for quick and easy self-diagnosis of bad breath.

The authors acknowledge funding from the National Research Foundation of Korea and the Nano Convergence Foundation.

The abstract that accompanies this article is available here.

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ITHACA, N.Y. - Cornell researchers have developed nanostructures that enable record-breaking conversion of laser pulses into high-harmonic generation, paving the way for new scientific tools for high-resolution imaging and studying physical processes that occur at the scale of an attosecond - one quintillionth of a second.

High-harmonic generation has long been used to merge photons from a pulsing laser into one, ultrashort photon with much higher energy, producing extreme ultraviolet light and X-rays used for a variety of scientific purposes. Traditionally, gases have been used as sources of harmonics, but a research team led by Gennady Shvets, professor of applied and engineering physics in the College of Engineering, has shown that engineered nanostructures have a bright future for this application.

The research is detailed in the paper "Generation of Even and Odd High Harmonics in Resonant Metasurfaces Using Single and Multiple Ultra-Intense Laser Pulses," published July 7 in Nature Communications. Maxim Shcherbakov, who conducted the research as a Cornell postdoctoral associate before becoming an assistant professor at the University of California, Irvine, is the lead author.

The nanostructures created by the team make up an ultrathin resonant gallium-phosphide metasurface that overcomes many of the usual problems associated with high-harmonic generation in gases and other solids. The gallium-phosphide material permits harmonics of all orders without reabsorbing them, and the specialized structure can interact with the laser pulse's entire light spectrum.

"Achieving this required engineering of the metasurface's structure using full-wave simulations," Shcherbakov said. "We carefully selected the parameters of the gallium-phosphide particles to fulfill this condition, and then it took a custom nanofabrication flow to bring it to light."

The result is nanostructures capable of generating both even and odd harmonics - a limitation of most other harmonic materials - covering a wide range of photon energies between 1.3 and 3 electron volts. The record-breaking conversion efficiency enables scientists to observe molecular and electronic dynamics within a material with just one laser shot, helping to preserve samples that may otherwise be degraded by multiple high-powered shots.

The study is the first to observe high-harmonic generated radiation from a single laser pulse, which allowed the metasurface to withstand high powers - five to 10 times higher than previously shown in other metasurfaces.

"It opens up new opportunities to study matter at ultrahigh fields, a regime not readily accessible before," Shcherbakov said. "With our method, we envision that people can study materials beyond metasurfaces, including but not limited to crystals, 2D materials, single atoms, artificial atomic lattices and other quantum systems."

Now that the research team has demonstrated the advantages of using nanostructures for high-harmonic generation, it hopes to improve high-harmonic devices and facilities by stacking the nanostructures together to replace a solid-state source, such as crystals.

In the race to combat climate change, capturing carbon dioxide (CO2) emissions has been touted as a simple road to reach net-zero emissions by 2050. While the science behind carbon capture is sound, current technologies are expensive and not optimized for all settings. A cover story in Chemical & Engineering News, the weekly newsmagazine of the American Chemical Society, highlights the current state of carbon capture and work being done to improve the process.

Although efficiency improvements and renewable power sources can help, they are often expensive and will not be enough to counter the billions of tons of CO2 sent into the atmosphere each year, writes Associate Editor Craig Bettenhausen. Carbon-capture technology, implemented at the source of CO2 emissions such as power plants, could largely negate those emissions. Despite its promise, only one commercial power plant is using this technology today. Interestingly, oil and gas companies -- the main producers of CO2 emissions -- are now unlikely allies of those who are developing capture methods, spurred by competition from cheap renewable energy and consumer demand for low-carbon options.

At present, the most common form of carbon capture uses solvents to absorb CO2 and let through other, less harmful gases. While this method is well understood, it requires up to 50% of a plant's energy output, making it not a particularly "green" solution. Scientists are working to develop the next generation of carbon-capture technology, with solid sorbents and membranes showing promise. These materials require less energy and are already in use at some sites with concentrated CO2 emissions. The immediacy of the issue has prompted companies to begin developing other methods, including the use of cryogenics and metal-organic frameworks to absorb the gas. While the U.S. government is working with companies to subsidize carbon capture, critics say that it distracts from investing in renewable energy and regulating polluters. Progress is being made, but experts warn that the next decade will be the deciding period in which to find a solution to CO2 emissions.

Domesticated rabbits come in all sizes and colors, including tiny Netherland Dwarfs, floppy-eared French lops, Flemish Giants, and fluffy Angoras.

These breeds belong to Europe's only rabbit species, originally limited to the Iberian Peninsula and Southern France and used for meat and fur since the last Ice Age, culminating in domestication about 1,500 years ago.

The Americas, on the other hand, have many rabbit species with ranges throughout both continents. The archaeological record shows rabbits were used as extensively in the Americas as they were on the Iberian Peninsula, with clear archaeological evidence that rabbits were being deliberately raised. Why, then, were rabbits domesticated in Europe and not the Americas?

Recent work by archaeologists Andrew Somerville of Iowa State University and UC Riverside's Nawa Sugiyama found a simple answer: European rabbits live readily in large social groups while American cottontail rabbits do not. The less social nature of American cottontails combined with greater species diversity created a situation where rabbit husbandry did not lead to domestication.

Sugiyama looked to Teotihuacan, a major city in Mexico about 2,000 years ago, where cottontail rabbits comprised 23% of the animal remains during the Classic period. This was more than any other animal used for meat, including wild deer, as well as domesticated turkeys and dogs. The proportion of rabbit bones increased toward the city center, suggesting they were probably being raised, not hunted.

Rabbits were buried at the Sun and Moon Pyramids and are found in the stomach contents of sacrificial carnivores, such as eagles and pumas. Rabbit bones found in the carnivore stomachs contain a type of carbon that indicates a diet unusually rich in corn or cactus, suggesting human-raised rabbits had, in turn, been fed to the carnivores.

"The rabbits were probably fed corn, but the carbon isotopes don't distinguish between corn and cactus, so we can't say for certain," Sugiyama said.

Moreover, 46% of the animal bones excavated in one apartment compound were from rabbits that had been fed a similar diet of agricultural crops, and the amount of phosphate in the floor of one room indicates a location where rabbits urinated and were probably housed. A stone statue of a rabbit was also found in the complex's central plaza, reinforcing the importance of rabbit husbandry to the residents.

A thousand years later, the 16th century Spanish conquistador Hernan Cortez described the sale of rabbits at the Aztec marketplace of Tlateloco. Over at least a millennia of husbandry and extensive use for food, fur, and ritual, however, the rabbits of Mexico did not become domesticated -- a mutualistic, multigenerational relationship characterized by human-controlled reproduction.

To understand why, Somerville compared the behavioral ecology of European rabbits and American cottontails against criteria that "prime" or preadapt animals for domestication. Animals that have been domesticated usually live in groups with resident males. They also have young that imprint easily and require parental care, a promiscuous mating system, tolerance for a wide variety of environments, and low reactivity to humans.

European and American rabbits were similar across all criteria except social behavior. European rabbits live in underground family burrows, called warrens, of up to 20 individuals that include males, who defend their breeding territory from other males. Warrens made it easy for people to locate and manage wild rabbit populations, then mimic those conditions in captivity, where rabbits readily reproduced.

American cottontails, on the other hand, are solitary, live entirely above ground, and tend to fight in enclosures together. Males do not defend a breeding territory and pursue more opportunistic mating strategies.

Somerville and Sugiyama conclude that their solitary nature, tendency to fight in enclosures, dispersed territories, and less predictable mating systems made it possible to raise rabbits without forming the kind of mutual relationship that would eventually give humans enough control over a species to direct its evolution. Greater species diversity also made it less likely that any one of them would become domesticated.

A new University of Chicago study has found that the drug masitinib may be effective in treating COVID-19.

The drug, which has undergone several clinical trials for human conditions but has not yet received approval to treat humans, inhibited the replication of SARS-CoV-2 in human cell cultures and in a mouse model, leading to much lower viral loads.

Researchers at UChicago's Pritzker School of Molecular Engineering (PME), working with collaborators at Argonne National Laboratory and around the world, also found that the drug could be effective against many types of coronaviruses and picornaviruses. Because of the way it inhibits replication, it has also been shown to remain effective in the face of COVID-19 variants.

"Inhibitors of the main protease of SARS-CoV-2, like masitinib, could be a new potential way to treat COVID patients, especially in early stages of the disease," said Prof. Savas Tay, who led the research. "COVID-19 will likely be with us for many years, and novel coronaviruses will continue to arise. Finding existing drugs that have antiviral properties can be an essential part of treating these diseases."

The results were published July 20 in Science.

A race to find COVID-19 treatments

When COVID-19 lockdowns began in March 2020, Tay and Nir Drayman, a postdoctoral fellow who specializes in virology, began to think about how they could help. To search for a better treatment for the disease, they began by screening a library of 1,900 clinically safe drugs against OC43, a coronavirus that causes the common cold and can be studied under regular biosafety conditions. They used cell cultures to determine the drugs' effect on infection.

They then gave the top 30 drug candidates to microbiology professor Glenn Randall, who tested them in cell cultures against the SARS-CoV-2 virus at the Howard Taylor Ricketts Laboratory, a BSL-3 facility at Argonne National Laboratory. Measurements in the high-containment lab revealed nearly 20 drugs that inhibit SARS-CoV-2.

They also sent the drug candidates to other collaborators to test against the 3CL protease, the enzyme within coronaviruses that allows them to replicate inside a cell. They found that of the drug candidates, masitinib completely inhibited the 3CL viral enzyme inside the cell, a fact that was confirmed by X-ray crystallography by Prof. Andrzej Joachimiak's group at Argonne. The drug specifically binds to the 3CL protease active site and inhibits further viral replication.

"That gave us a strong indication of how this drug works, and we became confident that it has a chance to work in humans," Drayman said.

Though masitinib is currently only approved to treat mast cell tumors in dogs, it has undergone human clinical trials for several diseases, including melanoma, Alzheimer's disease, multiple sclerosis, and asthma. It has been shown to be safe in humans but does cause side effects, including gastrointestinal disorders and edema, and could potentially raise a patient's risk for heart disease.

Drug effective against variants, other viruses

Next, the researchers worked with peers at the University of Louisville to test the drug in a mouse model. They found that it reduced the SARS-CoV-2 viral load by more than 99 percent and reduced inflammatory cytokine levels in mice.

In parallel, the researchers also began to test the drug in cell cultures against other viruses and found that it was also effective against picornaviruses, which include Hepatitis A, polio, and rhinoviruses that cause the common cold.

They also tested it in cell cultures against three SARS-CoV-2 variants, Alpha, Beta, and Gamma, and found that it worked equally well against them, since it binds to the protease and not to the surface of the virus.

Now, the team is working with the pharmaceutical company that developed the drug (AB Science) to tweak the drug to make it an even more effective antiviral. Meanwhile, masitinib itself could be taken to human clinical trials in the future to test it as a COVID-19 treatment.

"Masitinib has the potential to be an effective antiviral now, especially when someone is first infected and the antiviral properties of the drug will have the biggest effect," Drayman said. "This isn't the first novel coronavirus outbreak, and it's not going to be the last. In addition to vaccines, we need to have new treatments available to help those who have been infected."

Los Alamos, N.M., July 21, 2021--A team of scientists at Los Alamos National Laboratory propose that modulated quantum metasurfaces can control all properties of photonic qubits, a breakthrough that could impact the fields of quantum information, communications, sensing and imaging, as well as energy and momentum harvesting. The results of their study were released yesterday in the journal Physical Review Letters, published by the American Physical Society.

"People have studied classical metasurfaces for a long time," says Diego Dalvit, who works in the Condensed Matter and Complex Systems group at the Laboratory's Theoretical Division. "But we came up with this new idea, which was to modulate in time and space the optical properties of a quantum metasurface that allow us to manipulate, on-demand, all degrees of freedom of a single photon, which is the most elementary unit of light."

Metasurfaces are ultrathin structures that can manipulate light in ways not usually seen in nature. In this case, the team developed a metasurface that looked like an array of rotated crosses, which they can then manipulate with lasers or electrical pulses. They then proposed to shoot a single photon through the metasurface, where the photon splits into a superposition of many colors, paths, and spinning states that are all intertwined, generating so-called quantum entanglement--meaning the single photon is capable of inheriting all these different properties at once.

"When the metasurface is modulated with laser or electrical pulses, one can control the frequency of the refracted single photon, alter its angle of trajectory, the direction of its electric field, as well as its twist," says Abul Azad from the Center for Integrated Nanotechnologies at the Laboratory's Materials Physics and Applications Division.

By manipulating these properties, this technology could be used to encode information in photons traveling within a quantum network, everything from banks, quantum computers, and between Earth and satellites. Encoding photons is particularly desirable in the field of cryptography because "eavesdroppers" are unable to view a photon without changing its fundamental physics, which if done would then alert the sender and receiver that the information has been compromised.

The researchers are also working on how to pull photons from a vacuum by modulating the quantum metasurface.

"The quantum vacuum is not empty but full of fleeting virtual photons. With the modulated quantum metasurface one is able to efficiently extract and convert virtual photons into real photon pairs," says Wilton Kort-Kamp, who works in the Theoretical Division at the Lab's Condensed Matter and Complex Systems group.

Harnessing photons that exist in the vacuum and shooting them in one direction should create propulsion in the opposite direction. Similarly, stirring the vacuum should create rotational motion from the twisted photons. Structured quantum light could then one day be used to generate mechanical thrust, using only tiny amounts of energy to drive the metasurface.

Older adults may be slower to learn actions and behaviours that benefit themselves, but new research shows they are just as capable as younger people of learning behaviours that benefit others.

Researchers at the Universities of Birmingham and Oxford found that youngsters, in contrast, tend to learn much faster when they are making choices that benefit themselves.

The study, published in Nature Communications, focused on reinforcement learning - a fundamental type of learning in which we make decisions based on the positive outcomes from earlier choices. It allows us to adapt our choices to our environment by learning the associations between choices and their outcomes.

Dr Patricia Lockwood is senior author on the paper at the University of Birmingham's School of Psychology and Centre for Human Brain Health. She said: "Reinforcement learning is one of the key ways in which humans - as well as animals and even plants - learn from and adapt to their environment."

"We need to make decisions and learn all the time based on the positive or negative feedback we receive. This allows us to optimise our choices to choose the best course of action in the future from many possible alternatives. We find that older adults are worse than younger adults at learning from positive feedback on their own behaviour. However, surprisingly, when making choices that give positive feedback - money - to another person, older adults are just as good as younger adults".

In the study, the team worked with 80 younger and 80 older participants. They were each asked to make a series of choices between two symbols on a computer screen. After each selection, they received feedback on whether they got reward points from the selection they had made.

On some rounds, points translated into increased money for the participant, in others they translated into money for someone else. In a third, control condition, participants could get points but these weren't worth money for anyone.

The results revealed that, on average, the older group learned to choose the most advantageous option more slowly than the younger group when their selections would only benefit themselves. However, when making choices on behalf of another person, older people learned equally as fast as the younger group. Across all age groups, the researchers found that learning was slowest when the points weren't worth anything.

Dr Jo Cutler, lead author and also at the University of Birmingham, said: "We recognise that in general, cognitive processes and learning ability tend to get worse as people get older. So it's really interesting to see that when making choices that will benefit others, older adults' learning ability is preserved. By better understanding what motivates older people in this way, we can contribute to strategies that promote healthy ageing."

The research programme also yielded some surprising findings in terms of differences between the young and older adults in psychopathic traits, including lack of empathy and concern for others. The team found that these characteristics were lower in older adults, suggesting psychopathic traits are not fixed across a person's lifespan, but may tail off as we age. In older adults, their level of psychopathic traits explained differences in learning speed specifically when they were learning to benefit others.

Being more physically active and spending fewer hours per day sitting watching TV is linked to a substantially lower risk of developing obstructive sleep apnoea (OSA), according to new research published in the European Respiratory Journal [1]. It is the first study to simultaneously evaluate physical activity and sedentary behaviour in relation to OSA risk.

OSA is a condition where breathing stops and starts many times during sleep. It reduces oxygen levels in the blood and common symptoms include snoring, disrupted sleep and feeling excessively tired. Serious complications associated with poorly managed OSA include an increased risk of high blood pressure, stroke, heart attack, irregular heartbeat, and type 2 diabetes. It is estimated [2] that around 1 billion adults aged 30-69 years are affected by mild to severe OSA globally.

The study was led by Tianyi Huang, Assistant Professor and Associate Epidemiologist at Brigham and Women's Hospital and Harvard Medical School, USA. To examine whether being less physically active and more sedentary increases OSA risk, Professor Huang and colleagues analysed health data from more than 138,000 US men and women who did not have clinically diagnosed OSA at the beginning of the study. By the end of the study follow-up period of 10-18 years, 8,733 participants were reported to have OSA diagnoses.

The researchers accounted for other factors that can impact OSA risk within their analyses, including participants' age, body-mass index (BMI), and whether they smoked or drank alcohol.

When the researchers compared people who did activities equivalent to two hours per week of walking at an average pace with people whose activity level was equivalent to three hours of running per week, they found that the participants with the higher activity level had a 54% lower risk of developing OSA.

People who spent more than four hours per day sitting watching TV had a 78% higher OSA risk than the least sedentary people, while people who did sedentary work had a 49% increased risk of OSA compared with the least sedentary people.

However, the data suggests that for people who have to spend long hours sitting every day, such as people with office jobs, increasing physical activity in their leisure time can lower OSA risk. Similarly, those who are not able to do much physical activity due to physical constraints could also lower their OSA risk by reducing sedentary hours, by standing or doing other gentle activities more frequently.

Professor Huang explained: "We saw a clear relationship between levels of physical activity, sedentary behaviour and OSA risk. People who followed the current World Health Organization physical activity guidelines of getting at least 150 minutes of moderate activity per week, and who spent less than four hours per day sitting watching TV, had substantially lower OSA risk. Importantly, we saw that any additional increase in physical activity, and/or a reduction in sedentary hours, could have benefits that reduce the risk of developing OSA.

"The difference in OSA risk between sedentary work and time spent sitting watching TV could be explained by other behaviours that are related to those activities. For example, snacking and drinking sugary drinks is more likely to go along with watching TV compared with being sedentary at work or elsewhere, such as sitting during travelling. This could lead to additional weight gain, which we know to be a risk factor OSA."

Professor Anita Simonds, who was not involved in the research, is President of the European Respiratory Society and Consultant in Respiratory and Sleep Medicine at Royal Brompton Hospital, UK. She said: "OSA is a common and pervasive disorder that can have a serious impact on the quality of people's lives. Although OSA can be managed with modern treatments, only a minority of studies focus on prevention. Health professionals should prioritise prevention and support people who are at-risk of developing OSA to be more active before it is too late.

"This study adds to the evidence on the importance of maintaining an active lifestyle on preventing lung disease, and it is encouraging that even a small increase in physical activity or reduction in sedentary hours could reap potential benefits. It is therefore an important message to get across to our patients and their families in primary care and respiratory clinics."

The researchers say the study relied on self-reported health data, which is potentially less reliable, noting that future research could make use of wearable health monitoring technologies to improve the accuracy of the data.