Tech

Researchers with the Snyder Institute for Chronic Diseases at the Cumming School of Medicine (CSM) have discovered which gut bacteria help our immune system battle cancerous tumours and how they do it. The discovery may provide a new understanding of why immunotherapy, a treatment for cancer that helps amplify the body's immune response, works in some cases, but not others. The findings, published in Science, show combining immunotherapy with specific microbial therapy boosts the ability of the immune system to recognize and attack cancer cells in some melanoma, bladder and colorectal cancers.

Dr. Kathy McCoy, PhD, is a leading expert on the body's relationship with the microbiome. She and her team are focused on harnessing the power of the microbiome to improve health and treat diseases. McCoy says to harness and direct that power scientists need to better understand the role bacteria play in regulating the immune system.

"Recent studies have provided strong evidence that gut microbiota can positively affect anti-tumour immunity and improve the effectiveness of immunotherapy in treating certain cancers, yet, how the bacteria were able to do this remained elusive, " says McCoy, director of the International Microbiome Centre at the University of Calgary and principal investigator on the study. "We've been able to build on that work by showing how certain bacteria enhance the ability of T-cells, the body's immunity soldiers that attack and destroy cancerous cells."

First, the researchers identified bacterial species that were associated with colorectal cancer tumours when treated with immunotherapy. Working with germ-free mice, they then introduced these specific bacteria along with immune checkpoint blockade, a type of cancer immunotherapy. Research revealed that specific bacteria were essential to the immunotherapy working. The tumours shrank, drastically. For those subjects that did not receive the beneficial bacteria, the immunotherapy had no effect.

"We found that these bacteria produce a small molecule, called inosine," says Dr. Lukas Mager, MD, PhD, senior postdoctoral researcher in the McCoy lab and first author on the study. "Inosine interacts directly with T-cells and together with immunotherapy, it improves the effectiveness of that treatment, in some cases destroying all the colorectal cancer cells."

The researchers then validated the findings in both bladder cancer and melanoma. The next step in this work will be to study the finding in humans. The three beneficial bacteria associated with the tumours in mice have also been found in cancers in humans.

"Identifying how microbes improve immunotherapy is crucial to designing therapies with anti-cancer properties, which may include microbials," says McCoy. "The microbiome is an amazing collection of billions of bacteria that live within and around us everyday. We are in the early stage of fully understanding how we can use this new knowledge to improve efficacy and safety of anti-cancer therapy and improve cancer patient survival and well-being."

A Canadian-Finnish collaboration has led to the discovery of a novel magnetic compound in which two magnetic dysprosium metal ions are bridged by two aromatic organic radicals forming a pancake bond. The results of this study can be utilized to improve the magnetic properties of similar compounds. The theoretical investigation of the study was carried out by the Academy Research Fellow Jani O. Moilanen at the University of Jyväskylä, whereas the experimental work was performed at the University of Ottawa in the groups of Profs. Muralee Murugesu and Jaclyn L. Brusso. The research results were published in the well-recognized chemistry journal - Inorganic Chemistry Frontiers in July 2020 - with the cover art.

Magnets are used in many modern electronic devices ranging from mobile phones and computers to medical imaging devices. Besides the traditional metal-based magnets, one of the current research interests in the field of magnetism has been the study of single-molecule magnets consisting of metal ions and organic ligands. The magnetic properties of single-molecule magnets are purely molecular in origin, and it has been proposed that in the future, single-molecule magnets could be utilized in high-density information storage, spin-based electronics (spintronics), and quantum computers.

Unfortunately, most of the currently known single-molecule magnets only exhibit their magnetic properties at low temperatures near absolute zero (?273°c), which prevents their utilization in electronic devices. The first single-molecule magnet that retained its magnetization over the boiling point of liquid nitrogen (?196 °C) was reported in 2018. This study was a considerable breakthrough in the field of magnetic materials as it demonstrated that single-molecule magnets functioning at higher temperatures can be also realized.

Excellent magnetic properties of the reported compound at the elevated temperatures originated from the optimal three-dimensional structure of the compound. In theory, similar design principles could be used for single-molecule magnets containing more than one metal ion but controlling the three-dimensional structure of multinuclear compounds is much more challenging.

Bridging organic radicals were utilized in the novel compound

Instead of fully controlling the three-dimensional structure of the reported compound, a different design strategy was utilized in this study.

"Like dysprosium ions, organic radicals also have unpaired electrons that can interact with unpaired electrons of metal ions. Thus, organic radicals can be used to control the magnetic properties of a system along with metal ions. Particularly interesting organic radicals are bridging ones as they can interact with multiple metal ions. We employed this design strategy in our study, and surprisingly, we synthesized a compound where not only one but two organic radicals bridged two dysprosium ions as well as formed a pancake bond through their unpaired electrons", Prof. Muralee Murugesu from the University of Ottawa clarifies.

"Even though the formation of the pancake bond between two radicals is well known, this was the first time that the pancake bond was observed between two metal ions. The interaction between organic radicals is often referred to as pancake bonding because the three-dimensional structure of interacting organic radicals resembles a stack of pancakes", Prof. Jaclyn L. Brusso from the University of Ottawa tells.

The pancake bond in the novel compound was very strong. Therefore, the unpaired electrons of the organic radicals did not interact strongly with the unpaired electrons of the dysprosium ions and the compound functioned as a single-molecule magnet only at low temperatures. However, the study paves the way for the new design strategy for novel multinuclear single-molecule magnets and has initiated further research.

"Computational chemistry methods provided important insights into the electronic structure and magnetic properties of the compound that can be utilized in future studies. By choosing the right kind of organic radicals we can not only control the nature of the pancake bond between the radicals but also enhance the magnetic properties of the compound overall", Academy Research Fellow Jani O. Moilanen from the University of Jyväskylä comments.

The tenth named tropical cyclone of the Atlantic Ocean hurricane season was named today, Aug. 13, after NASA-NOAA's Suomi NPP satellite provided a nighttime image of the storm.

Tropical Storm Josephine developed from Tropical Depression 11. Over the last two days, Tropical Depression 11 has been moving through the Central Atlantic Ocean and was slow to organize. Satellite imagery indicated the depression became more organized and reached tropical storm strength on Aug. 13.

Another Record-Breaker for the Season

Josephine is the earliest tenth tropical storm of record in the Atlantic, with the next earliest tenth storm being Tropical Storm Jose on August 22, 2005.

NASA's Night-Time View

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a nighttime image of Josephine on Aug. 13 at 2 a.m. EDT (0500 UTC). The imagery showed that Josephine had strong thunderstorms surrounding its center of circulation and fragmented thunderstorms wrapping into the low-level center from the northern quadrant. The image was created using the NASA Worldview application.

The National Hurricane Center (NHC) noted, "Satellite imagery shows that the convective pattern associated with Josephine has become a little better organized since the last advisory (at 5 a.m. EDT), with a ragged central convective feature and a weak band in the northern semicircle."

Josephine's Formation Advisory

At 11 a.m. EDT (1500 UTC) on Aug. 13, NHC announced the formation of Tropical Storm Josephine. At that time, the center was located near latitude 13.7 degrees north and longitude 49.2 degrees west. Josephine was located about 975 miles (1,565 km) east-southeast of the Northern Leeward Islands.

Josephine was moving toward the west-northwest near 15 mph (24 kph), and this general motion is expected to continue for the next few days followed by a turn toward the northwest late this weekend or early next week. The estimated minimum central pressure is 1005 millibars.

Recent satellite wind data indicate that maximum sustained winds have increased to near 45 mph (75 kph) with higher gusts. Some additional strengthening is forecast during the next 48 hours.

NHC cautions that interests in the Leeward Islands should monitor the progress of this system.

Lisle, Ill. (August 13) -- Central America is one of the most diverse floristic regions in the world, but a lack of comprehensive plant records and knowledge of its endangered, endemic tree species impedes conservation work.

In a new research paper published in Forest Ecosystems, The Morton Arboretum Center for Tree Science Research Fellow Richard Condit, PhD, provided the first comprehensive checklist to include geographic ranges by using an innovative, repeatable method for assessing extinction risk of trees in poorly studied areas. The method involves synthesizing field data with available online records to form a fully vetted list of the trees of Panama and their estimated geographic ranges. These range sizes provide a quantitative basis for assessing extinction risk of poorly studied tropical tree species, and offer a starting point for researchers to plan conservation efforts.

"A fundamental question in species conservation is, how many are left?" said Condit, who has studied the trees of Panama for 35 years. "Full geographic ranges of individual species are seldom known, and we found that the forest inventory plots being studied in the country lacked a global geographic perspective. Now that we have estimated range sizes, we can compare Panama's ecosystem to the rest of the world, as well as plan and allocate conservation resources more effectively."

The authors estimate that 16.2% of Panama's 3,043 tree species had ranges less than 20,000 km2, a range that often signals a status of endangered, according to the International Union for Conservation of Nature (IUCN) standards. This percentage of narrow endemics is proportionate to that of North America. Researchers also noted that the country's tree census plots excluded rare endemic species, noting that the network of 66 tree plots captured 27% of total tree flora in Panama, but only 7.5% of narrow endemics.

The Morton Arboretum conducted the research as part of its efforts to prevent global tree extinctions and secure threatened species in Central America and beyond.

"This was the first comprehensive effort to pull together global databases, rigorously vet all the data, and create a comprehensive distribution of species in an understudied country like Panama," said Chuck Cannon, PhD, director of the Center for Tree Science at The Morton Arboretum. "Richard and his team have given us a strategy for finding where to go, what trees to study, and how to be more effective in the Arboretum's efforts to conserve rare tree species around the world."

The next step for Condit and his team is to estimate population sizes and make demographic assessments of extinction risk, starting with the potential red-listed trees located on tree census plots.

JUPITER, FL--Chemists at Scripps Research have efficiently created three families of complex, oxygen-containing molecules that are normally obtainable only from plants.

These molecules, called terpenes, are potential starting points for new drugs and other high-value products--marking an important development for multiple industries. In addition, the new approach could allow chemists to build many other classes of compounds.

The chemistry feat is detailed in the Aug. 13 edition of the journal Science.

The key to this new method of making molecules is the harnessing, or hijacking, of natural enzymes--from bacteria, in this case--to assist in complex chemical transformations that have been impractical or impossible with synthetic chemistry techniques alone, says principal investigator Hans Renata, PhD, an assistant professor in the Department of Chemistry at Scripps Research.

Natural enzymes that help build molecules in cells usually perform only one or two highly specific tasks. But the Scripps Research team showed that natural enzymes, even without modification, can be made to perform a wider range of tasks.

"We think that in general, enzymes are a mostly untapped resource for solving problems in chemical synthesis," Renata says. "Enzymes tend to have some degree of promiscuous activity, in terms of their ability to spur chemical reactions beyond their primary task, and we were able to take advantage of that here."

Tapping into enzymes' hidden talents

Enzymes help build molecules in all plant, animal and microbial species. Inspired by their efficiency in constructing highly complex molecules, chemists for more than half a century have used enzymes in the lab to help build valuable compounds, including drug compounds--but usually these compounds are the same molecules the enzymes help build in nature.

Harnessing natural enzymes in a broader way, according to their basic biochemical activity, is a new strategy with vast potential.

"Our view now is that whenever we want to synthesize a complex molecule, the solution probably already exists among nature's enzymes--we just have to know how to find the enzymes that will work," says senior author Ben Shen, PhD, chair of the Department of Chemistry on the Florida campus and director of Scripps Research's Natural Products Discovery Center.

The team succeeded in making nine terpenes known to be produced in Isodon, a family of flowering plants related to mint. The complex compounds belong to three terpene families with related chemical structures: ent-kauranes, ent-atisanes, and ent-trachylobanes. Members of these terpene families have a wide range of biological activities including the suppression of inflammation and tumor growth.

A recipe for synthesis success

The synthesis of each compound, in less than 10 steps for each, was a hybrid process combining current organic synthesis methods with enzyme-mediated synthesis starting from an inexpensive compound called stevioside, the main component of the artificial sweetener Stevia.

The chief hurdle was the direct replacement of hydrogen atoms with oxygen atoms in a complex pattern on the carbon-atom skeleton of the starting compound. Current organic synthesis methods have a limited arsenal for such transformations. However, nature has produced many enzymes that can enable these transformations--each capable of performing its function with a degree of control unmatched by man-made methods.

"Being an interdisciplinary research group, we were fully aware of the limitations of current organic synthesis methods, but also of the many unique ways that enzymes can overcome these limitations--and we had the insights to combine traditional synthetic chemistry with enzymatic methods in a synergistic fashion," Renata says.

The three enzymes used, which were identified and characterized by Shen, Renata and colleagues only last year, are produced naturally by a bacterium--one of the 200,000-plus species in the Microbial Strain Collection at Scripps Research's Natural Products Discovery Center.

"We were able to use these enzymes not only to modify the starting molecules, or scaffolds as we call them, but also to turn one scaffold into another so that we could transform a terpene from one family into a terpene from a different family," says second author Emma King-Smith, a PhD student in the Renata lab.

The chemists now intend to use their new approach to make useful quantities of the nine compounds, as well as chemical variants of the compounds, and, with collaborating laboratories, explore their properties as potential drugs or other products.

"With our strategy, we can make these highly oxidized diterpenes much more easily and in larger quantities than would be possible by isolating them from the plants where they are found naturally," says first author Xiao Zhang, PhD, a postdoctoral research associate in the Renata lab.

Just as importantly, the researchers say, they are working to identify reactions and enzymes that will allow them to extend their approach to other classes of molecules.

Central to all these efforts is the ongoing development of methods to sift through the DNA of microbes and other organisms to identify the enzymes they encode--and predict the activities of those enzymes. Billions of distinct enzymes exist in plants, animals, and bacteria on Earth and only a tiny fraction of them have been catalogued to date.

"We're excited about the potential of discovering new and useful enzymes from our strain library here at Scripps Research," Renata says. "We think that will enable us to solve many other problems in chemical synthesis."

To judge the overall effectiveness of cover crops and choose those offering the most ecosystem services, agricultural scientists must consider the plants' roots as well as above-ground biomass, according to Penn State researchers who tested the characteristics of cover crop roots in three monocultures and one mixture.

"Almost everything that we know about the growth of cover crops is from measuring the above-ground parts and yet some of the benefits that we want to get from cover crops come from the roots," said researcher Jason Kaye, professor of soil biogeochemistry. "This study shows us that what we see above ground is sometimes -- but not always -- reflective of the benefits below ground."

Cover crops are widely used to increase the quantity of organic carbon returned to the soil between cash crops such as corn, wheat and soybean, as well as to limit erosion and to fix or add nitrogen to the soil. Cover crop roots are known to play an essential role in increasing soil organic carbon levels, Kaye noted, but the root traits that impact carbon levels vary widely among cover crop species, and this variation has yet to be characterized.

Recently, Kaye pointed out, cover crop mixtures have expanded in popularity as a way to increase the diversity of cover crop benefits. His research group in the College of Agricultural Sciences has been conducting a continuous experiment evaluating the effectiveness of various cover crop mixtures since 2011.

In the latest study, conducted at Penn State's Russell E. Larsen Agricultural Research Center at Rock Springs, recently published in Renewable Agriculture and Food Systems, researchers evaluated cover crop treatments including monocultures of triticale, canola and crimson clover as well as a five-species mixture dominated by those three species.

They tested the quantity, quality and spatial distribution of those cover crop roots to learn about root-trait variation among species, and how that variation impacts mixture design. They took root cores from in-row and between-row locations to a depth of about 16 inches in both fall and spring from cover crops planted after winter wheat.

Researchers also assessed cumulative carbon inputs for the entire rotation to determine cover crop and cash crop root carbon contributions. They measured the vertical and horizontal distribution of root biomass, the ratio of root biomass to aboveground biomass - known as the root-to-shoot ratio -- and related that to the amount of nitrogen in the plants to determine how these parameters differed between cover crop treatments.

Cover crop mixtures increased total carbon inputs to soil because they simultaneously had high root and shoot inputs and they promoted higher carbon inputs from corn crop residues, Kaye explained.

"The corn crop was more productive following the mixtures than following grasses, and while we harvest a lot of that productivity, some gets left behind in residues," he said. "I think this is really interesting because it shows that the effect of cover crops on soil carbon are not just related to their own roots and shoots, but also how they affect growth of the cash crops."

The study revealed root trait differences among the three important winter annual cover crops, canola, crimson clover and triticale, lead researcher Joseph Amsili pointed out. The research uncovered several important root traits, he added, including the high root-to-shoot ratio and large production of between-row roots for triticale, which is a hybrid of winter wheat and cereal rye.

"The five-species mix was associated with increased quantity and distribution of roots compared to a crimson clover monoculture, which shows the benefits of combining legumes that have limited root biomass with brassica and grass species that produce greater root biomass, but provide more nitrogen," said Amsili. Now an extension associate in the Soil and Crop Sciences Section in the School of Integrative Plant Sciences at Cornell University, he was a graduate student in the Department of Ecosystem Science and Management at Penn State when he spearheaded the research.

The study is important because the increased knowledge of cover crop root traits it yielded improves the understanding of the linkages between root traits and the services cover crops provide, Kaye explained. Going forward, he expects to find cover crops and design cover crop mixtures that deliver unexpected ecosystem benefits and added boosts to cash crops that follow.

"We'll now be able to think about what we want to occur in the soil and then design mixtures that have the root traits that are best able to provide those benefits," he said. "Advancing research on cover crop root traits serves as a strong foundation for designing mixtures with complementary root traits. I envision that we will exploit lots of different cover crop plants for different traits, both above and below ground."

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

Household contact the greatest risk for transmission of COVID-19
Asymptomatic patients less likely to infect close contacts compared to severe cases
Secondary transmission acquired from public transportation was rare

Researchers from Southern Medical University, Guangzhou, China traced more than 3,410 close contacts of 391 COVID-19 index cases between January and March 2020 to evaluate the risk for disease transmission in different settings. They found that risk for secondary transmission of COVID-19 was less than 4 percent among close contacts of persons with COVID-19. In addition, secondary infections acquired while using public transportation were rare. In contrast, 1 in 10 household contacts was found to be infected.

The researchers also found that patients with more clinically severe disease were more likely to infect their close contacts than were less severe index cases. Those with asymptomatic cases were the least likely to infect their close contacts. Manifestation of certain symptoms, such as expectoration, in index cases was also associated with an increased risk for infection in their close contacts. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-2671.

Leesburg, VA, August 13, 2020--According to ARRS' American Journal of Roentgenology (AJR), clinicians do not read a considerable proportion of second-opinion radiology reports--"a situation that can be regarded as an appreciable but potentially reversible waste of health care resources," the authors of this AJR "Health Care Policy and Quality" article concluded.

Conducted by three radiologists from University Medical Center Groningen in The Netherlands, this retrospective study included 4,696 consecutive second-opinion reports of external imaging examinations authorized by subspecialty radiologists at a tertiary care institution between January 1 and December 31, 2018.

Of the 4,696 second-opinion reports, 537 were not read by a clinician, corresponding to a frequency of 11.4% (95% CI, 10.6-12.3%).

The imaging modality with the highest rate of not being read was sonography (20/32 [62.5%]), the requesting specialty with the highest rate was pediatrics (26/77 [33.8%]), and the radiologic subspecialty with the highest rate was interventional radiology (12/23 [52.2%]).

On multivariate logistic regression analysis, first author Sabine A. Heinz found that the following variables remained significantly and independently associated with the second-opinion report not being read:

inpatient status (odds ratio [OR], 163.26; p sonography as the imaging modality (OR, 5.07; p = 0.014),

surgery (OR, 0.18; p interventional radiology as the subspecialty of the radiologist who authorized the second-opinion report (OR, 3.52; p = 0.047).

Noting that the National Healthcare Authority of The Netherlands allows up to €100 ($118) to be charged for each second-opinion reading, and that a typical second-opinion reading takes approximately 15 minutes, Heinz and colleagues calculated that the 537 unread second-opinion reports could cost as much as €53,700 ($63,427), as well as approximately 134.25 hours of radiologist interpretation time.

"Although these numbers appear modest, they pertain to a single institution during a 1-year time period," Heinz et al. wrote, adding that cumulative nationwide figures would raise these totals, "possibly substantially," and that the number of unread second-opinion reports will likely increase, "given the projected rise in future second-opinion requests."

Furthermore, since opening the report in the electronic patient file system does not necessarily mean that the clinician actually read said report, Heinz and team contend that the rate of reports not being read (11.4%) is likely an underestimation.

Ultimately, "if subspecialty radiologists and clinicians take proven determinants into account," the authors of this AJR article maintained, "the amount of second-opinion readings with limited additional clinical value may be reduced."

New observations by the NASA/ESA Hubble Space Telescope suggest that the unexpected dimming of the supergiant star Betelgeuse was most likely caused by an immense amount of hot material ejected into space, forming a dust cloud that blocked starlight coming from Betelgeuse's surface.

Betelgeuse is an aging, red supergiant star that has swelled in size as a result of complex, evolving changes in the nuclear fusion processes in its core. The star is so large that if it replaced the Sun at the centre of our Solar System, its outer surface would extend past the orbit of Jupiter. The unprecedented phenomenon of Betelgeuse's great dimming, eventually noticeable to even the naked eye, began in October 2019. By mid-February 2020, the brightness of this monster star had dropped by more than a factor of three.

This sudden dimming has mystified astronomers, who sought to develop theories to account for the abrupt change. Thanks to new Hubble observations [1], a team of researchers now suggest that a dust cloud formed when superhot plasma was unleashed from an upwelling of a large convection cell on the star's surface and passed through the hot atmosphere to the colder outer layers, where it cooled and formed dust. The resulting cloud blocked light from about a quarter of the star's surface, beginning in late 2019. By April 2020, the star had returned to its normal brightness.

Several months of Hubble's ultraviolet-light spectroscopic observations of Betelgeuse, beginning in January 2019, produced an insightful timeline leading up to the star's dimming. These observations provided important new clues to the mechanism behind the dimming. Hubble saw dense, heated material moving through the star's atmosphere in September, October, and November 2019. Then, in December, several ground-based telescopes observed the star decreasing in brightness in its southern hemisphere.

"With Hubble, we see the material as it left the star's visible surface and moved out through the atmosphere, before the dust formed that caused the star appear to dim," said lead researcher Andrea Dupree, associate director of The Center for Astrophysics | Harvard & Smithsonian. "We could see the effect of a dense, hot region in the southeast part of the star moving outward."

"This material was two to four times more luminous than the star's normal brightness," she continued. "And then, about a month later, the southern hemisphere of Betelgeuse dimmed conspicuously as the star grew fainter. We think it is possible that a dark cloud resulted from the outflow that Hubble detected. Only Hubble gives us this evidence of what led up to the dimming."

The team began using Hubble early last year to analyse the massive star. Their observations are part of a three-year Hubble study to monitor variations in the star's outer atmosphere. The telescope's sensitivity to ultraviolet light allowed researchers to probe the layers above the star's surface, which are so hot that they emit mostly in the ultraviolet region of the spectrum and are not seen in visible light. These layers are heated partly by the star's turbulent convection cells bubbling up to the surface.

"Spatially resolving a stellar surface is only possible in favourable cases and only with the best available equipment," said Klaus Strassmeier of the Leibniz Institute for Astrophysics Potsdam (AIP) in Germany. "In that respect, Betelgeuse and Hubble are made for each other."

Hubble spectra, taken in early and late 2019 and in 2020, probed the star's outer atmosphere by measuring spectral lines of ionised magnesium. From September to November 2019, the researchers measured material passing from the star's surface into its outer atmosphere. This hot, dense material continued to travel beyond Betelgeuse's visible surface, reaching millions of kilometres from the star. At that distance, the material cooled down enough to form dust, the researchers said.

This interpretation is consistent with Hubble ultraviolet-light observations in February 2020, which showed that the behaviour of the star's outer atmosphere returned to normal, even though in visible light it was still dimming.

Although Dupree does not know the cause of the outburst, she thinks it was aided by the star's pulsation cycle, which continued normally though the event, as recorded by visible-light observations. Strassmeier used an automated telescope of the Leibniz Institute for Astrophysics called STELLar Activity (STELLA) to measure changes in the velocity of the gas on the star's surface as it rose and fell during the pulsation cycle. The star was expanding in its cycle at the same time as the convective cell was upwelling. The pulsation rippling outward from Betelgeuse may have helped propel the outflowing plasma through the atmosphere.

The red supergiant is destined to end its life in a supernova blast and some astronomers think the sudden dimming may be a pre-supernova event. The star is relatively nearby, about 725 light-years away, so the dimming event would have happened around the year 1300, as its light is just reaching Earth now.

Dupree and her collaborators will get another chance to observe the star with Hubble in late August or early September. Right now, Betelgeuse is in the daytime sky, too close to the Sun for Hubble observations.

Bird and reptile tears aren't so unlike our own, shows a new study in Frontiers in Veterinary Science. But the differences could provide insights into better ophthalmic treatments for humans and animals, as well as a clues into the evolution of tears across different species.

"Discovering how tears are able to maintain the ocular homeostasis, even in different species and environmental conditions, is crucial for understanding the evolution and adaptation processes, and is essential for the discovery of new molecules for ophthalmic drugs," says first author Prof. Arianne P. Oriá, of the Federal University of Bahia, in Salvador, Brazil.

Tears play a critical role in maintaining healthy eyesight across species. But up to now, researchers have only studied tears in a short list of mammals, including humans, dogs, horses, monkeys and camels. To get a more complete picture of how tears work in other species, Oriá and her collaborators have now added seven species of birds and reptiles to this list.

"Although birds and reptiles have different structures that are responsible for tear production, some components of this fluid (electrolytes) are present at similar concentrations as what is found in humans," explains Oriá. "But the crystal structures are organized in different ways so that they guarantee the eyes´ health and an equilibrium with the various environments."

Oriá and her collaborators worked together with veterinarians from a conservation center, a wild animal care center and a commercial breeder to collect tear samples from healthy captive animals. The study was limited to animals that were kept as pets or as part of conservation efforts, and the researchers collected tears as part of the animals' normal physical check-ups.

The animals in the study included macaws, hawks, owls and a type of parrot, as well as tortoises, caimans and sea turtles. For comparison, the authors also collected tears from 10 healthy human volunteers.

By looking at the composition of the tears, the authors found that all of the tear types contained similar amounts of electrolytes such as sodium and chloride, although bird and reptile tears had slightly higher concentrations. Owl and sea turtle tears also showed higher levels of urea and protein. After measuring the composition of the tears, the authors also looked at the crystals that formed when the tear fluid dried out. Researchers can use this crystallization pattern to uncover certain types of eye disease, as well as other variations between tear types.

Although the different species had similar tear composition, surprisingly the crystals showed more variation. Sea turtle and caiman tear crystals were particularly unique, probably as an adaptation to their aquatic environments.

Tear research still only reflects a small number of species and this study was limited to captive animals. But future research of additional species could continue to expand our understanding of tear types, and also help guide better treatments for both animals and humans.

"This knowledge helps in the understanding of the evolution and adaption of these species, as well as in their conservation," adds Prof. Oriá.

A New Zealand-led international study of the crabeater seal population in Antarctica aims to understand environmental impacts on one of the southern-most mammals in the world.

With funding from The Pew Charitable Trusts, University of Canterbury (UC) scientists have been using satellite images of Antarctica and the power of citizen science to uncover the secret lives of crabeater seals in the largest ever survey of the Weddell Sea--one of Earth's last wildernesses.

"We searched satellite photos for crabeater seals in the Weddell Sea, with help from over 2000 volunteers around the world covering an area of sea ice the size of Fiji," says UC Gateway Antarctica scientist Dr. Michelle LaRue, a lecturer of Antarctic Marine Science in UC's School of Earth and Environment (Te Kura Aronukurangi).

This is the largest survey of sea ice in the Weddell Sea and the most broadly distributed study on crabeater seals in a single year. Working with Dr. LaRue, lead author Dr. Mia Wege, a post-doctoral researcher from UC Science's School of Earth and Environment, now at the University of Pretoria, is a marine predator ecologist with a specific interest in seals and Antarctica.

"I study their behavior, foraging ecology, diet, abundance and distribution. But really, seals are just the means to understand impacts of climate change on species living in extreme environments. We combined Google Earth-like imagery, volunteers and statistical modeling to figure out where crabeater seals are likely to be found in the Weddell Sea--a place that is likely refugia for ice-dependent species, as the climate continues to change," Dr. Wege says.

"We found that crabeater seal distribution overlapped mostly with Antarctic krill habitat. This is important because Antarctic krill is not only preferred prey for these seals, but also the vast majority of Antarctic predators. Krill are also a target species for fisheries in the Southern Ocean. Knowing crabeater seal distribution is valuable conservation information, particularly because a Marine Protected Area is currently being planned in the Weddell Sea."

Global leaders will consider protecting over 2.2 million square kilometers of the Weddell Sea this October when the Commission for the Conservation of Antarctic Marine Living Resources annual meeting takes place.

Some areas had never been surveyed for seals before, due to the thick, multi-year pack-ice that precludes ship-based surveys in the Weddell Sea.

The UC team collaborated with Dr. Leo Salas from Point Blue Conservation Science, a non-profit organization from California dedicated to developing climate-smart science for conservation.

"Drs LaRue and Wege are world-class Antarctic researchers, and working with volunteers means that people without typical scientific training get to be directly involved in the scientific process," says Dr. Salas. "We expect this research to significantly help shape the conversation about where and how to best protect the Weddell Sea ecosystem."

"Community science means anyone in the world with an internet connection can do research alongside us by reviewing the satellite images and telling us what they see," says Dr. LaRue. This method has been successfully used to find Weddell seals in Antarctic fast-ice, another project led by Dr. LaRue.

"But now, as a pilot study, we searched for crabeater seals in the pack-ice," she says. Pack-ice (ice floating in the middle of the Southern Ocean) is more jagged, with ridges and shadows (due to freezing and thawing of ice) which makes finding seals in the satellite images much harder.

This study, along with other work by Dr. LaRue at UC, suggests that using satellite photos to study Antarctic predators could become a valuable and cost-effective long-term monitoring method in a place that is hard to reach most of the year--now made even more inaccessible by COVID-19 restrictions.

Most people don't know that humans fish for, and consume, krill, she says. The shrimp-like crustaceans that whales, penguins and crabeater seals eat can be found in krill oil supplements, for example.

"So since we effectively are competing with these animals for their food, we have an obligation to ensure we don't damage the ecosystem," Dr. LaRue says.

"And one way to keep track of how the system is functioning is to study krill predators, like crabeater seals. Since we found very few locations with seals across a huge space in the Weddell Sea, creating a marine protected area may be a prudent action, to set aside the region from irreversible ecosystem damage."

Researchers in China have taken the first step towards a new way of treating gastric wounds by using a microrobot combined with the new concept of "in situ in vivo bioprinting" to carry out tissue repair inside the body.

Their study, published today in the IOP Publishing journal Biofabrication, establishes proof-of-concept for this new method in the field of bioprinting.

Co- author Professor Tao Xu, from Tsinghua University, Beijing, said: "Gastric wall injury is a common problem in the digestive tract, and about 12 per cent of the world's population suffer from it to varying degrees. Bioprinting - delivering new cells directly to the wound site to repair the tissue - offers a potentially very useful way to treat the problem.

"The difficulty is that current bioprinting technology focuses on external sites. Bioprinters are normally quite large, and cannot be applied to inner tissue repair without invasive surgery to give enough room for the printing operation. To overcome this, we developed a microrobot that enters the body via an endoscope to carry out tissue repair inside the body."

The bioprinting platform Professor Xu and the co-author, Professor Xu's PhD student Wenxiang Zhao developed is a Delta robot composed of a fixed base, moving platform and three identical kinematic chains. To be as minimally-invasive as possible, it can fold itself down when entering the patients' body, then unfold before beginning the bioprinting operation.

Mr. Zhao, also from Tsinghua University, said: "We tested the system in two ways. First, with a biological model of a human stomach and an endoscope, to mimic the insertion and printing operation elements of the process. Second, we carried out a bioprinting test in a cell culture dish to test how effective the device was at bioprinting viable cells and repairing wounds.

"Both tests showed promising results. A 10-day cell culture showed that printed cells remained at a high viability and a steady proliferation, which indicated good biological function of the cells in printed tissue scaffolds."

Professor Xu added: "Although only a first step, this study has verified the feasibility of this concept for treatment for gastric wall injuries. More work is needed to bring it to full realisation, including reducing the size of the bioprinting platform and developing bioinks. Our future studies will concentrate on these areas."

COLUMBUS, Ohio - Walking with a purpose - especially walking to get to work - makes people walk faster and consider themselves to be healthier, a new study has found.

The study, published online earlier this month in the Journal of Transport and Health, found that walking for different reasons yielded different levels of self-rated health. People who walked primarily to places like work and the grocery store from their homes, for example, reported better health than people who walked mostly for leisure.

"We found that walking for utilitarian purposes significantly improves your health, and that those types of walking trips are easier to bring into your daily routine," said Gulsah Akar, an associate professor of city and regional planning in The Ohio State University Knowlton School of Architecture.

"So, basically, both as city planners and as people, we should try to take the advantage of this as much as possible."

The study used data from the 2017 National Household Travel Survey, a U.S. dataset collected from April 2016 to May 2017.

The researchers analyzed self-reported health assessments from 125,885 adults between the ages of 18 and 64. Those adults reported the number of minutes they spent walking for different purposes - from home to work, from home to shopping, from home to recreation activities and walking trips that did not start at their homes.

And, the survey respondents ranked how healthy they were on a scale of 1 to 5. The dataset the researchers analyzed included more than 500,000 trips.

The researchers - Akar and Ohio State doctoral student Gilsu Pae - found that walking for any duration, for any purpose, increased how healthy a person felt.

But they also found that an additional 10 minutes of walking per trip from home for work-based trips - say, from a person's house to the bus stop 10 minutes away - increased that person's odds of having a higher health score by 6 percent compared with people who walk for other reasons. People who walked from home for reasons not connected to work, shopping or recreation were 3 percent more likely to have a higher health score.

And, the researchers found, people who walked for work walked faster - on average, about 2.7 miles per hour - than people who walked for other reasons. People who walked for recreational purposes - say, an after-dinner stroll - walked, on average, about 2.55 miles per hour.

The researchers also found that walking trips that begin at home are generally longer than walking trips that begin somewhere else. The team found that 64 percent of home-based walking trips last at least 10 minutes, while 50 percent of trips that begin elsewhere are at least that long.

Akar has studied the ways people travel for years, and said she was surprised to see that walking for different purposes led to a difference in how healthy people believed they were.

"I was thinking the differences would not be that significant, that walking is walking, and all forms of walking are helpful," she said. "And that is true, but walking for some purposes has significantly greater effect on our health than others."

Akar said the findings suggest that building activity into parts of a day that are otherwise sedentary - commuting by foot instead of by car, for example - can make a person feel healthier.

"That means going to a gym or a recreation center aren't the only ways to exercise," Akar said. "It's an opportunity to put active minutes into our daily schedules in an easy way."

After an oil spill or leak, it's important to act fast. If the oil has gotten into soil, scientists need to rapidly assess how much oil there is and how far it spread. It's a process that has always been costly and time-consuming.

Nuwan Wijewardane at University of Nebraska-Lincoln knew there had to be a better way. He and his team found a new method using state-of-the-art technology that is faster and cheaper. It lets scientists get to work quicker on restoring the soil.

"Accidental releases of oil at production and distribution sites can pose serious environmental issues if not treated," explains Wijewardane. "This demands remedial actions to assist in the rapid restoration of the ecosystem to its pre-contamination state. It is critical to be able to estimate concentration levels in impacted soil quickly and easily."

The traditional methods for analyzing these soils are done in the laboratory and involve multiple steps. It requires collecting samples from the spill site and then taking them off-site for analysis. These increase the cost, time, and labor of the project.

"It costs about $50 per sample," says Wijewardane. "And that does not include the cost of the labor needed to collect samples from the field. In addition, it can take days or maybe weeks to get results."

The research team thought they could accomplish two things. One was using a faster and cheaper technology called Vis-NIR spectroscopy. The other was finding a way to measure the oil content in soil without having to take the time to gather so many samples from the spill site.

The Vis-NIR spectroscopy technology works by sending wavelengths of energy at a sample and measuring what is absorbed or reflected. Different chemical substances do this very specifically based on their makeup. So, it's able to tell scientists a lot about a sample.

The data they receive from the technology has to be compared to a model. They found they could construct accurate model samples mostly in the laboratory, with only a few samples from the site needed. Adding just a few field samples, rather than relying solely on them, is a process called "spiking." This reduction of time and labor necessary at the oil spill site makes their method rapid and cheap.

During "spiking," the data from the field samples is added into the original model. This helps customize the model to make it more accurate for the specific location.

The cost of the VisNIR-based method is just a few dollars per sample. The results are almost instant. Another added benefit is that the tool can be taken right into the field to speed up the overall project.

Wijewardane has been working on soil spectroscopy for some time. He is interested in how to use it to estimate soil properties. He is glad this study highlights another application of this technology that can help the environment recover from crude oil contamination.

The next steps in the work are to make the technology more suitable to use directly in the field. Conservation and protecting the environment is an important task globally, especially since humans still use crude oil as a key source of energy.

"As long as we extract and use crude oil, there is a risk of environmental contamination that can threaten the ecosystem's balance," Wijewardane says. "When it happens, we need immediate actions to detect it, evaluate the situation, and recommend remedial actions. This is where a rapid, cheap, and accurate technique in the field can accelerate the process."

Read more about this research in the Journal of Environmental Quality, a publication of the American Society of Agronomy, Crop Science Society of America and Soil Science Society of America. This research was supported by the Chevron Energy Technology Company.

Hydrostatic pressurization can effectively lead to new and improved material properties. However, most of the novel material properties are only retainable at high-pressure states, and therefore warrant no practical applicability at ambient conditions. Recently, a team of international scientists led by Dr. Lingping Kong and Dr. Gang Liu from HPSTAR reported permanent and irreversible transition of 2D hybrid Dion-Jacobson lead iodide perovskite to 3D perovskite phase at ambient conditions after pressure treatment. This work suggests the usefulness of high-pressure technique in preparing materials for real-situation applications. The results, as reported in PNAS, marks crucial steps in utilizing pressure for ex-situ and ambient-environment applicability in engineering light-absorbing materials for high-performance optoelectronics and luminescence.

Harnessing the pressure-induced properties has been a long-standing effort in the quest of exotic materials at ambient environment. Nevertheless, due to the order-disorder-order and recrystallization behaviors of material structures, desirable properties attainable at high-pressure states tend to be reversed at ambient pressure. From this sense, choosing materials with modifiable basis is imperatively important for permanent change in properties. Being a class of 2D metal halide perovskites, Dion-Jacobson perovskites represent a new material paradigm that is different from conventional Ruddlesden-Popper perovskite phase, in which D-J perovskites do not have the van der Waals gaps as encountered in R-P counterparts due to the divalent nature of interlayer organics. Such exotic structure ensures much shortened interlayer distance and greater structural rigidity, two important factors that can make sure irreversible structural phase transitions, and thus is electronically and atomically more resembling the 3D bulk phase. The scientist observed permanent and notable transition of 2D D-J phase (3AMP)(MA)3Pb4I13 to 3D MAPbI3 after 40 GPa pressure treatment, as proved by X-ray diffraction crystal structure after decompression.