Researchers call for worldwide biosurveillance network to protect from diseases

Decentralized approach more cost-effective and efficient than current systems

SAN DIEGO ZOO GLOBAL

 

The emergence of COVID-19 is a powerful reminder of how unchecked wildlife trade can lead to the spillover spread of viruses between wildlife and humans. Understanding that wholesale bans on trade can affect community livelihoods and food security, the pandemic underscores the need for widespread pathogen screening and monitoring to better understand, predict and contain outbreaks in wildlife and humans.

To date, global biosurveillance has consisted of centralized efforts led by governmental and specialized health agencies. A group of authors--including eight researchers from San Diego Zoo Global--writing in the journal Science this week offer an efficient approach that may be more resilient to fluctuations in government support and could be utilized even in remote areas.

Given the importance for the health of a global population, the team of scientists recommend a "decentralized" disease surveillance system, enabled by modern pathogen-detection methods, which builds in-country capacity for addressing challenges. Utilizing portable molecular screening that is both cost-effective and relatively easy to use, this network would take a more fundamentally proactive approach to wildlife screening, they write.

"The COVID-19 crisis has shown that the international wildlife trade is a global system in need of greater oversight," said Elizabeth Oneita Davis, Ph.D., conservation social scientist in Community Engagement at San Diego Zoo Global, who was one of the authors. "However, ill-conceived measures such as 'blanket bans' could affect millions of people and drive these activities deeper underground, further impeding our efforts to understand and reduce demand for wildlife."

The network should expand monitoring beyond human disease outbreaks to encompass a broader understanding of pathogens and evaluate their spillover risk (of spreading from wildlife to humans or vice versa), they write. To this end, surveillance focal points should include wildlife markets and farms, as well as free-ranging populations of "high-risk" wildlife.

"Since the H1N1 outbreak of 2009, which spurred governmental responses such as PREDICT to begin active virus hunting in zoonotic hotspots, genomic technologies have transformed radically," said Mrinalini Erkenswick Watsa, Ph.D., lead author and conservation geneticist on San Diego Zoo Global's Population Sustainability team. "Sequencing the genome of a virus is now feasible on miniature sequencers, directly at the point of sample collection. Today, we can more directly and powerfully survey wildlife health, identify areas of high spillover potential and contribute to minimizing those behaviors, to keep human and wildlife populations safe," she said.

Key to this approach is the creation of a pathogen database to provide early warnings of spillover potential, and assist in containment and development of therapeutic treatments.

"A decentralized approach to biosurveillance would more readily address wildlife and ecosystem health, and therefore conservation as a whole," said Steven V. Kubiski, DVM, Ph.D., a veterinary pathologist on San Diego Zoo Global's Disease Investigations team, who co-authored the perspective piece. "The ability to test multiple populations is just the beginning--a centralized location for deposition, analysis and reporting would add even more value, and could serve as an open-access resource."

The authors note that beyond endangering human health, emerging infectious diseases can imperil wildlife populations that have not evolved resistance to unfamiliar pathogens.

Additionally, the authors call for an internationally recognized standard for wildlife trade, the risks of which they call the "largest unmet challenge" for infectious disease surveillance. Despite the known risks, little monitoring takes place in wildlife markets like the one believed to be the original vector of the SARS-CoV-2 virus.

"Decentralized pathogen screening in wildlife lends itself not only to early detection of pathogen spillover into humans, but helps conservation veterinarians and disease experts understand the natural host-pathogen relationship, allowing us to better conserve wildlife populations and save species," said Caroline Moore, DVM, Ph.D., Steel Endowed Pathology Fellow and veterinary toxicologist on San Diego Zoo Global's Disease Investigations team, who was among the co-authors.

"The proposed disease surveillance model will help us inventory naturally occurring pathogens in different taxa across the globe, enabling us to track future changes in viruses and ecosystem health that are relevant to both humans and wildlife populations," added Carmel Witte, Ph.D., wildlife epidemiologist on San Diego Zoo Global's Disease Investigations team.

The authors point out the value of biobanking efforts, including those of San Diego Zoo Global's Frozen Zoo®, in assisting the worldwide surveillance effort.

This decentralized system is consistent with the collaborative, holistic disease mitigation strategy of the One Health approach, used by the Centers for Disease Control and Prevention. This approach seeks to decrease the threat of disease through the conservation of nature and ecosystem function, accounting for domestic animals and all other human-related factors.

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About San Diego Zoo Global

Bringing species back from the brink of extinction is the goal of San Diego Zoo Global. As a leader in conservation, the work of San Diego Zoo Global includes on-site wildlife conservation efforts (representing both plants and animals) at the San Diego Zoo, San Diego Zoo Safari Park, and San Diego Zoo Institute for Conservation Research, as well as international field programs on six continents. The work of these entities is made accessible to over 1 billion people annually, reaching 150 countries via social media, our websites and the San Diego Zoo Kids network, in children's hospitals in 12 countries. The work of San Diego Zoo Global is made possible with support from our incredible donors committed to saving species from the brink of extinction. To learn more, visit SanDiegoZooGlobal.org or connect with us on Facebook.

Study finds less impact from wildfire smoke on climate

Observations suggest smaller warming effects of brown carbon than published model assessments

DOE/LOS ALAMOS NATIONAL LABORATORY

 

LOS ALAMOS, N.M., July 9, 2020--New research revealed that tiny, sunlight-absorbing particles in wildfire smoke may have less impact on climate than widely hypothesized because reactions as the plume mixes with clean air reduce its absorbing power and climate-warming effect. In a unique megafire study, a Los Alamos National Laboratory-led research team studied the properties of smoke from Arizona's massive Woodbury Fire last summer using a powerful set of observing techniques.

"These observations may be useful for those trying to represent organic light absorbing aerosols, or brown carbon, in climate models by identifying how they age, as well as understanding processes affecting how strongly they absorb light and cause warming," said James Lee, lead author on a paper released in JGR: Atmospheres this week and a Los Alamos postdoctoral researcher.

The Woodbury Fire burned nearly 124,000 acres for more than a month before it was contained. With powerful instruments including an aerosol mass spectrometer at Los Alamos' Center for Aerosol Forensic Experiments (CAFÉ), researchers from Los Alamos and New Mexico Tech measured the chemical, physical, and optical properties of ambient aerosol and trace gas concentrations in four large plumes in real time. The team found that the composition of the plumes as well as aerosol properties within the plumes are more varied than expected. More oxidation of smoke lowers its sunlight absorbing potential and lessens its climatic impact.

"Wildfire plumes are complex and change quickly," said Allison Aiken, an atmospheric chemist at Los Alamos and coauthor of the study. "Particles at the plume's center have different shapes and chemistries than at its edge."

The team was able to observe intact and more-disperse plumes that aged more than half a day while traveling 300 miles across New Mexico, retaining relatively unchanged aerosols at the plume's core but providing valuable insight to how the smoke transforms as it mixes with cleaner air.

"This is important as we need to capture the physicochemical changes that occur as plumes are transported long distances to model the climate impacts correctly and to understand the human health impacts at different locations and distances from the source," Aiken said.

While the team observed that the Woodbury fire emissions contained brown carbon that absorbed light at a potency that validated previous observations, this was only the case in the core of the plumes. At the edges, organic aerosols absorbed far less light.

Fine-scale results revealed that mixing and oxidation lightened the brown carbon, reducing its ability to absorb light and cause warming. This implies that the warming effects of wildfire brown carbon is likely smaller than published model assessments.

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The research team included Lee, Aiken, Petr Chylek and Manvendra Dubey of Los Alamos and Kip Carrico of New Mexico Tech in Socorro, N.M.

Funding:

This research was supported by Office of Science of the U.S. Department of Energy (DOE), Office of Biological and Environmental Research (BER), Atmospheric System Research (ASR) Program, and Office of Workforce Development for Teachers and Scientists. Additional support was received from the National Science Foundation, the Los Alamos National Laboratory Laboratory Directed Research and Development program, and the New Mexico Consortium.

Publication:

Optical and chemical analysis of absorption enhancement by mixed carbonaceous aerosols in the 2019 Woodbury, AZ fire plume; James E. Lee, Manvendra K. Dubey, Allison C. Aiken, Petr Chylek, Christian M. Carrico; DOI: 10.1029/2020JD032399

About Los Alamos National Laboratory

Los Alamos National Laboratory, a multidisciplinary research institution engaged in strategic science on behalf of national security, is managed by Triad, a public service oriented, national security science organization equally owned by its three founding members: Battelle Memorial Institute (Battelle), the Texas A&M University System (TAMUS), and the Regents of the University of California (UC) for the Department of Energy's National Nuclear Security Administration.

Los Alamos enhances national security by ensuring the safety and reliability of the U.S. nuclear stockpile, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to energy, environment, infrastructure, health, and global security concerns. LA-UR-20-25008

Revealing winners & losers in projected future climates

New research reveals how winners & losers from climate change can be identified based on their ability to adapt to rising temperatures

FLINDERS UNIVERSITY

 

IMAGE: THE RANGE OF THE THREE STUDY SPECIES OF RAINBOWFISHES IN AUSTRALIA. PHOTOS BY GUNTHER SCHMIDA. view more 

CREDIT: PNAS

New research reveals how winners & losers from climate change can be identified based on their ability to adapt to rising future temperatures.

In the first study of its kind published in PNAS, Flinders University evolutionary biologists have shown that resilience or vulnerability to future climates is influenced by the thermal conditions of the climatic regions where species evolved.

The study compared thermal tolerance and gene expression (which genes are activated within a cell) in subtropical, desert and temperate Australian rainbowfishes.

Evolutionary biologist Professor Luciano Beheregaray says subtropical species were the winners in future climates because evolution suits their local conditions given these fish have the ability to turn on and off a larger number of heat stress genes in hotter climates.

The study shows that subtropical species have greater capacity to adapt to future climates than desert species, and that temperate species are the most vulnerable.

By looking at how all the genes are expressed in current temperatures and in temperatures projected for 2070, the researchers produced a catalogue of genes that informs about the adaptive capacity to climate change.

"Resilience or vulnerability to climate change is expected to be influenced by the thermal conditions where species are found, but we knew very little about this, and hardly anything about how this might vary across different climatic regions", says co-author Dr Jonathan Sandoval-Castillo.

"Our results suggest that the vulnerability of species to climate change will be highly influenced by geographic factors, emphasising the value of assessments of climate traits for more accurate estimates of population impacts and the way ecosystems will ultimately respond", says co-author and PhD student Katie Gates.

The findings can also be extended to many non-migratory species, aquatic or terrestrial, under pressure due to climate change.

"This information is important for identifying biodiversity at high risk of extinction and to develop ways to help them to adapt and persist. This includes restoring lost habitat and actively moving populations to more favourable climatic locations, while we still have time", says Professor Beheregaray.

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"Adaptation of plasticity to projected maximum temperatures and across climatically defined bioregions" by Flinders University evolutionary biologists Professor Luciano Beheregaray, Dr Jonathan Sandoval-Castillo, Katie Gates and Dr Chris Brauer and by collaborators Prof Louis Bernatchez (Université Laval, Canada) and Dr Steve Smith (University of Vienna, Austria) is published in the Proceedings of the National Academy of Science (PNAS) 7 July 2020

Link: https://www.pnas.org/content/early/2020/07/06/1921124117

UQ researchers solve a 50-year-old enzyme mystery

UNIVERSITY OF QUEENSLAND

 

IMAGE: 'THIS INFORMATION PROVIDES NEW INSIGHTS INTO AN IMPORTANT ENZYME -- ACETOHYDROXYACID SYNTHASE -- A TARGET FOR MORE THAN 50 COMMERCIAL HERBICIDES.' view more 

CREDIT: THE UNIVERSITY OF QUEENSLAND

Advanced herbicides and treatments for infection may result from the unravelling of a 50-year-old mystery by University of Queensland researchers.

The research team, led by UQ's Professor Luke Guddat, revealed the complete three-dimensional structure of an enzyme, providing the first step in the biosynthesis of three essential amino acids - leucine, valine and isoleucine.

"This is a major scientific advance, which has been pursued globally by chemists for half a century," Professor Guddat said.

"This information provides new insights into an important enzyme - acetohydroxyacid synthase - a target for more than 50 commercial herbicides.

"It's also a potential target for new drugs to treat infections such as tuberculosis and invasive Candida infections."

Using advanced techniques such as cryo-electron microscopy and X-ray crystallography, the team deciphered the structure of the plant and fungal versions of the enzyme.
"We identified how this highly complex structure is assembled, which is the highly unusual shape of a Maltese Cross," Professor Guddat said.
"Coincidently, the Maltese Cross also features as a part of UQ's logo."

Professor Guddat said the discovery could have big implications for global agriculture.

"Sulfometuron is a herbicide that targets this enzyme, and was widely used in the 1990s for wheat crop protection throughout Australia," he said.

"But today it is completely ineffective due to the development of resistance.

"With this new insight, we will be able to make changes to existing herbicides, restoring options for future herbicide application."

Professor Guddat said the enzyme was only found in plants and microbes, not in humans.

"For this reason, the herbicides and drugs that it targets are likely to be safe and non-toxic to all mammals," he said.

"And another surprising finding of the research was the role that the molecule known as ATP plays in the regulation of the enzyme.

"Normally ATP plays a role in providing energy to all living cells," Professor Guddat said.

"However, here it is acting like a piece of glue to hold the structure together."

"They're fascinating findings for us, and we're excited for new opportunities for targeted design of next-gen herbicides and antimicrobial agents."

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The majority of the study was undertaken by Dr Thierry Lonhienne and UQ PhD candidate, Yu Shang Low, who worked closely with the ShanghaiTech University, China to obtain the cryo-EM images for the plant enzyme.

The research has been published in Nature (DOI: 10.1038/s41586-020-2514-3).

Oil spill clean- up gets doggone hairy

First comparison of natural-origin sorbent materials for land-based oil spills

UNIVERSITY OF TECHNOLOGY SYDNEY

 

Oil spill disasters on land cause long-term damage for communities and the natural environment, polluting soils and sediments and contaminating groundwater.

Current methods using synthetic sorbent materials can be effective for cleaning up oil spills, but these materials are often expensive and generate large volumes of non-biodegradable plastic wastes. Now the first comparison of natural-origin sorbent materials for land-based oil spills, including peat moss, recycled human hair, and dog fur, shows that sustainable, cheaper and biodegradable options can be developed.

The University of Technology Sydney (UTS) project found that dog fur and human hair products - recycled from salon wastes and dog groomers - can be just as good as synthetic fabrics at cleaning up crude oil spills on hard land surfaces like highway roads, pavement, and sealed concrete floors. Polypropylene, a plastic, is a widely-used fabric used to clean up oil spills in aquatic environments.

"Dog fur in particular was surprisingly good at oil spill clean-up, and felted mats from human hair and fur were very easy to apply and remove from the spills." lead author of the study, UTS Environmental Scientist Dr Megan Murray, said. Dr Murray investigates environmentally-friendly solutions for contamination and leads The Phyto Lab research group at UTS School of Life Sciences.

"This is a very exciting finding for land managers who respond to spilled oil from trucks, storage tanks, or leaking oil pipelines. All of these land scenarios can be treated effectively with sustainable-origin sorbents," she said.

The sorbents tested included two commercially-available products, propylene and loose peat moss, as well as sustainable-origin prototypes including felted mats made of dog fur and human hair. Prototype oil-spill sorbent booms filled with dog fur and human hair were also tested. Crude oil was used to replicate an oil spill. The results of the study are published in Environments.

The research team simulated three types of land surfaces; non-porous hard surfaces, semi-porous surfaces, and sand, to recreate common oil-spill scenarios.

"We found that loose peat moss is not as effective at cleaning up oil spills on land compared to dog fur and hair products, and it is not useful at all for sandy environments." Dr Murray said.

"Based on this research, we recommend peat moss is no longer used for this purpose. Given that peat moss is a limited resource and harvesting it requires degrading wetland ecosystems, we think this is a very important finding." she said.

The research concluded that, for now, sandy environments like coastal beaches can still benefit from the use of polypropylene sorbents, but further exploration of sustainable-origin sorbents is planned.

The researchers say that future applications from the research include investigating felted mats of sustainable-origin sorbents for river bank stabilisation, as well as the removal of pollutants from flowing polluted waters, similar to existing membrane technology.

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Farmers' climate change conundrum: Low yields or revenue instability

CORNELL UNIVERSITY

ITHACA, N.Y. - Climate change will leave some farmers with a difficult conundrum, according to a new study by researchers from Cornell University and Washington State University: Either risk more revenue volatility, or live with a more predictable decrease in crop yields.

As water shortages and higher temperatures drive down crop yields in regions that depend heavily on seasonal snow, the choice to use more drought-tolerant crop varieties comes at a cost, according to model projections detailed in the paper "Water Rights Shape Crop Yield and Revenue Volatility Tradeoff for Adaptation in Snow Dependent Systems," published June 10 in Nature Communications.

The study examined the Yakima River Basin in Washington, where a complex combination of snow, reservoirs and water rights controls the availability of irrigation water. That water dictates the success of some of the U.S.' largest producers of wheat, corn, potatoes, pears, cherries, grapes, apples and hops. With proper snowfall and melt, total agricultural productivity in the basin can reach more than $4 billion a year.

The research team sought to quantify climate change's direct and indirect effects on irrigated agriculture in the basin. Researchers also wanted to know if drought-resistant crop varieties could help recover productivity during times of drought.

Climate risk modeling is a specialty of Patrick Reed, the Joseph C. Ford Professor of Engineering at Cornell's School of Civil and Environmental Engineering. In this collaborative study, Reed's group built on prior research at Washington State University that developed a modeling platform connecting crop growth and development, land-surface hydrology and river-system processes. The model simulates dam operations and prioritizes the allocation of water among different sectors within the Yakima River Basin.

The team found that higher water stress and temperatures led to lower crop yield, as anticipated, said Keyvan Malek, a postdoctoral researcher in Reed's group and lead author of the study.

"However, the models show that year-to-year variability in expected crop yields goes down because the difference between the best and worst case yields is reduced," said Malek. "While this is not a positive result, year-to-year fluctuations in crop yield revenue are strongly important in how crop insurance programs balance revenue fluctuations."

The team then used its model to explore the potential of new drought-tolerant crop varieties, which are expected to improve annual yields under climate change. The results showed that although those varieties could significantly improve the average yield, farmers could also experience much higher revenue volatility from crop production.

"Typical and best-case annual yields are much higher," said Jennifer Adam, Berry Distinguished Professor of Engineering at Washington State University and co-author of the study. "But climate change still is likely to cause severe droughts where current water management institutions in the Yakima River Basin simply cannot provide enough water, and there are severe worst-case crop failures."

The researchers argue that the best outcomes for crop yield and revenue volatility must be through a simultaneous improvement in crop varieties - for example, by preserving agrobiodiversity - and in water systems, such as through improvements in water-governing institutions and infrastructure.

It is important to carefully capture a snow-dependent region's specific management constraints while being innovative with climate adaptation strategies, the researchers said.

"Otherwise, systems may unintentionally strike the wrong balance as they trade off improving average yields and farmers' revenue volatility," Reed said.

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Viral dark matter exposed: Metagenome database detects phage-derived antibacterial enzyme

Scientists demonstrate that the information about host bacteria-bacteriophage (phage) associations derived from world`s first metagenome analysis is useful for the development of phage therapies against intestinal pathobionts.

OSAKA CITY UNIVERSITY

IMAGE: LET'S GIVE OUR SPECIAL "PHAGE " ATTACK TO THOSE EVIL C. DIFFICILE! (ILLUSTRATION BY HIDEAKI MIYAUCHI) view more 

CREDIT: SATOSHI UEMATSU, OSAKA CITY UNIVERSITY

In a pioneer study published in Cell Host & Microbe - Researchers at Osaka City University and The Institute for Medical Science, The University of Tokyo, reported intestinal bacterial and viral metagenome information from the fecal samples of 101 healthy Japanese individuals. This analysis, leveraging host bacteria-phage associations, detected phage-derived antibacterial enzymes that control pathobionts. As proof-of-concept, phage-derived endolysins are shown to regulate C. difficile infection in mice.

Abnormalities in human intestinal microflora, known as dysbiosis, are connected to various diseases. Altered microbial diversity impairs the beneficial effects of host intestinal microflora, which cause some symbiotic commensal bacteria to acquire virulence traits, proliferate, and become directly involved in the development of disease. These bacteria are referred to as "pathobionts", which are distinct from opportunistic pathogens.

C. difficile, which is a Gram-positive, spore-forming anaerobic bacterium, is a pathobiont and the representative cause of nosocomial diarrhea following antibiotic treatment. Since antibiotic usage has the risk of killing beneficial bacteria and promoting dysbiosis, the development of methods to specifically manipulate intestinal pathobionts is essential.

"Phages were sure to be applicable as a highly specific therapy for intestinal pathobiont elimination", believed Professor Satoshi Uematsu. The infectious associations between phages and bacteria in the human intestine is essential information for the development of phage therapies. Known as "viral dark matter" as it had yet to be understood, researchers obtained metagenome information about bacteria-phage associations from the fecal samples of 101 healthy individuals through the development of a virome analysis pipeline. Based on this information, researchers screened C. difficile-specific phages and identified novel antibacterial enzymes, both in vitro and in vivo.

"The accumulation of more metagenomic information on intestinal phages and bacteria will open up the possibility of developing treatments for a variety of dysbiosis-related diseases", say Dr. Kosuke Fujimoto and Prof. Seiya Imoto.

SEE PHAGE, PHAGES, BIOPHAGE

Flaring, massively

KyotoU's new Seimei telescope detects enormous 'superflare' on nearby star

ANOTHER REMINDER WHY IN ALL CULTURES THE SUN IS GOD

KYOTO UNIVERSITY

IMAGE: OBSERVING THE STELLAR FLARES ON AD LEONIS 16 LIGHT YEARS AWAY. ITS LOWER TEMPERATURE MAKES IT A PRIME TARGET TO STUDY FLARES AND THE MORE EXPLOSIVE 'SUPERFLARE' view more 

CREDIT: NATIONAL ASTRONOMICAL OBSERVATORY OF JAPAN

Japan -- The cold, dark chaos of space is filled with mystery.

Fortunately, the ways in which we can peer into the mists of the void are increasing, and now include Kyoto University's 3.8 meter Seimei telescope.

Using this new instrument -- located on a hilltop in Okayama to the west of Kyoto -- astronomers from Kyoto University's Graduate School of Science and the National Astronomical Observatory of Japan have succeeded in detecting 12 stellar flare phenomena on AD Leonis, a red dwarf 16 light years away. In particular, one of these flares was 20 times larger than those emitted by our own sun.

"Solar flares are sudden explosions that emanate from the surfaces of stars, including our own sun," explains first author Kosuke Namekata.

"On rare occasions, an extremely large superflare will occur. These result in massive magnetic storms, which when emitted from our sun can significantly effect the earth's technological infrastructure."

Hence understanding the properties of superflares can be vital, but their rareness means that data from our sun is difficult to gather. This has led researchers to look for exoplanets similar to earth, and to examine the stars they orbit.

Writing in the Publications of the Astronomical Society of Japan, the team reports on a long week of setting the sights of Seimei -- along with other observational facilities -- to AD Leonis.

This M-type red dwarf has temperatures lower than that of our sun, resulting in a high incidence of flares. The team expected a number of these to be large, and were astounded to then detect a superflare on their very first night of observations.

"Our analyses of the superflare resulted in some very intriguing data," Namekata explains.

Light from excited hydrogen atoms of the superflare exhibited an amount of high-energy electrons roughly one order of magnitude greater than typical flares from our sun.

"It's the first time this phenomenon has been reported, and it's thanks to the high precision of the Seimei Telescope," says Namekata.

The team also observed flares where light from excited hydrogen atoms increased, but did not correspond with an increase in brightness across of the rest of the visible spectrum.

"This was new for us as well, because typical flare studies have observed the continuum of the light spectrum -- the broad range of wavelengths -- rather than energy coming from specific atoms," continues Namekata.

The high-quality of these data was thanks to the new telescope, which the team hopes will open doors to new revelations regarding extreme space events.

Kazunari Shibata, leader of the study, concludes, "More information on these fundamental stellar phenomena will help us predict superflares, and possibly mitigate magnetic storm damage here on earth."

"We may even be able to begin understanding how these emissions can affect the existence -- or emergence -- of life on other planets."

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The paper "Optical and X-ray observations of stellar flares on an active M dwarf AD Leonis with Seimei Telescope, SCAT, NICER and OISTER" appeared 10 July 2020 in the journal Publications of the Astronomical Society of Japan, with doi: 10.1093/pasj/psaa051

About Kyoto University

Kyoto University is one of Japan and Asia's premier research institutions, founded in 1897 and responsible for producing numerous Nobel laureates and winners of other prestigious international prizes. A broad curriculum across the arts and sciences at both undergraduate and graduate levels is complemented by numerous research centers, as well as facilities and offices around Japan and the world. For more information please see: http://www.kyoto-u.ac.jp/en

Cosmic cataclysm allows precise test of general relativity

MAX PLANCK INSTITUTE FOR PHYSICS

IMAGE: THE MAGIC TELESCOPE SYSTEM AT THE ROQUE DE LOS MUCHACHOS OBSERVATORY, LA PALMA, CANARY ISLANDS, SPAIN view more 

CREDIT: GIOVANNI CERIBELLA/MAGIC COLLABORATION

In 2019, the MAGIC telescopes detected the first Gamma Ray Burst at very high energies. This was the most intense gamma-radiation ever obtained from such a cosmic object. But the GRB data have more to offer: with further analyses, the MAGIC scientists could now confirm that the speed of light is constant in vacuum - and not dependent on energy. So, like many other tests, GRB data also corroborate Einstein's theory of General Relativity. The study has now been published in Physical Review Letters.

Einstein's general relativity (GR) is a beautiful theory which explains how mass and energy interact with space-time, creating a phenomenon commonly known as gravity. GR has been tested and retested in various physical situations and over many different scales, and, postulating that the speed of light is constant, it always turned out to outstandingly predict the experimental results. Nevertheless, physicists suspect that GR is not the most fundamental theory, and that there might exist an underlying quantum mechanical description of gravity, referred to as quantum gravity (QG). Some QG theories consider that the speed of light might be energy dependent. This hypothetical phenomenon is called Lorentz invariance violation (LIV). Its effects are thought to be too tiny to be measured, unless they are accumulated over a very long time. So how to achieve that? One solution is using signals from astronomical sources of gamma rays. Gamma-ray bursts (GRBs) are powerful and far away cosmic explosions, which emit highly variable, extremely energetic signals. They are thus excellent laboratories for experimental tests of QG. The higher energy photons are expected to be more influenced by the QG effects, and there should be plenty of those; these travel billions of years before reaching Earth, which enhances the effect.

GRBs are detected on a daily basis with satellite borne detectors, which observe large portions of the sky, but at lower energies than the ground-based telescopes like MAGIC. On January 14, 2019, the MAGIC telescope system detected the first GRB in the domain of teraelectronvolt energies (TeV, 1000 billion times more energetic than the visible light), hence recording by far the most energetic photons ever observed from such an object. Multiple analyses were performed to study the nature of this object and the very high energy radiation.

Artist's impression of a gamma ray burst observed by the MAGIC telescope system and satellite observatories.

Tomislav Terzi?, a researcher from the University of Rijeka, says: "No LIV study was ever performed on GRB data in the TeV energy range, simply because there was no such data up to now. For over twenty years we were anticipating that such observation could increase the sensitivity to the LIV effects, but we couldn't tell by how much until seeing the final results of our analysis. It was a very exciting period."

Naturally, the MAGIC scientists wanted to use this unique observation to hunt for effects of QG. At the very beginning, they however faced an obstacle: the signal that was recorded with the MAGIC telescopes decayed monotonically with time. While this was an interesting finding for astrophysicists studying GRBs, it was not favorable for LIV testing. Daniel Kerszberg, a researcher at IFAE in Barcelona said: "when comparing the arrival times of two gamma-rays of different energies, one assumes they were emitted instantaneously from the source. However, our knowledge of processes in astronomical objects is still not precise enough to pinpoint the emission time of any given photon". Traditionally the astrophysicists rely on recognizable variations of the signal for constraining the emission time of photons. A monotonically changing signal lacks those features. So, the researchers used a theoretical model, which describes the expected gamma-ray emission before the MAGIC telescopes started observing. The model includes a fast rise of the flux, the peak emission and a monotonic decay like that observed by MAGIC. This provided the scientists with a handle to actually hunt for LIV.

A careful analysis then revealed no energy-dependent time delay in arrival times of gamma rays. Einstein still seems to hold the line. "This however does not mean that the MAGIC team was left empty handed", said Giacomo D'Amico, a researcher at Max Planck Institute for Physics in Munich; "we were able to set strong constraints on the QG energy scale". The limits set in this study are comparable to the best available limits obtained using GRB observations with satellite detectors or using ground-based observations of active galactic nuclei.

Cedric Perennes, postdoctoral researcher at the university of Padova added: "We were all very happy and feel privileged to be in the position to perform the first study on Lorentz invariance violation ever on GRB data in TeV energy range, and to crack the door open for future studies!"

In contrast to previous works, this was the first such test ever performed on a GRB signal at TeV energies. With this seminal study, the MAGIC team thus set a foothold for future research and even more stringent tests of Einstein's theory in the 21st century. Oscar Blanch, spokesperson of the MAGIC collaboration, concluded: "This time, we observed a relatively nearby GRB. We hope to soon catch brighter and more distant events, which would enable even more sensitive tests."

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CONTACTS:

Oscar Blanch Bigas, PhD
Spokesperson of the MAGIC Collaboration
IFAE
Campus Universitat Autònoma de Barcelona. Edifici Ciencies Nord, 08013, Barcelona, Spain
blanch@ifae.es

Dominik Elsässer, PhD
Outreach Coordinator of the MAGIC Collaboration
Technische Universität Dortmund
Experimentelle Physik 5b
Dortmund, Deutschland
Dominik.elsaesser@tu-dortmund.de

Otago researchers find link between rape and breathing problems

UNIVERSITY OF OTAGO

 

Rape and sexual trauma may have long-lasting consequences for physical health as well as mental health, University of Otago researchers have found.

The team of researchers, led by respiratory specialist Professor Bob Hancox and sexual health specialist Dr Jane Morgan from Waikato DHB, found a history of rape is associated with "dysfunctional breathing" in both women and men, and with late-onset asthma diagnosis in women.

"Dysfunctional breathing", which is also known as Hyperventilation Syndrome, involves breathing too deeply or too rapidly. People can present with chest pain and a tingling sensation in the fingertips and around the mouth and it may accompany a panic attack.

While previous studies have found that a history of adverse events and psychological trauma, including sexual trauma, are associated with self-reported asthma, links with other respiratory problems have not been examined. Professor Hancox explains the team set out to assess whether the experience of being raped - an extreme form of psychological trauma - was associated with dysfunctional breathing among participants in the Dunedin Multidisciplinary Health and Development Study.

This world-renowned study is a longitudinal investigation of health and behaviour in a group of 1037 people born in Dunedin in 1972 or 1973 and followed regularly throughout their lives.

Nearly 20 per cent of women and 4 per cent of men in the study reported being raped at some stage throughout their life. Both men and women who had reported being raped were more likely to have dysfunctional breathing at 38 years of age.

Rape was also associated with self-reported diagnoses of asthma and symptoms of wheeze among women, but not men.

"If this is a true cause-and-effect association, these analyses indicate that 23 per cent of all asthma among women at 38 years of age, or nearly a third of adult-onset asthma could be attributed to rape."

While both rape and the outcome of dysfunctional breathing were less common among men, the association between rape and hyperventilation syndrome was equally strong - or even stronger - among men who reported rape.

The Otago researchers believe this is the first epidemiological study to investigate the possible origins of hyperventilation syndrome.

"The findings indicate that dysfunctional breathing may be a consequence of severe psychological trauma and are consistent with case reports of sexual abuse in patients with other patterns of breathing difficulty," Professor Hancox explains.

"Health professionals should recognise the possibility of prior traumatic experiences triggering either dysfunctional breathing or late-onset asthma and consider whether psychological counselling or other forms of therapy would help their patients," he says.

The researchers focused on rape because it is a particularly traumatic experience that can be clearly defined, but Professor Hancox says it is likely that other forms of sexual and non-sexual abuse may have similar effects.

"We need to investigate whether other forms of sexual, physical and psychological trauma are also associated with breathing pattern disorders."

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The research was recently published in the European Respiratory Journal.