Wednesday, December 30, 2020

Army research leads to more effective training model for robots

U.S. ARMY RESEARCH LABORATORY

Research News

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IMAGE: NEW ARMY RESEARCH REDUCES THE UNPREDICTABILITY OF CURRENT TRAINING REINFORCEMENT LEARNING POLICIES SO THAT THEY ARE MORE PRACTICALLY APPLICABLE TO PHYSICAL SYSTEMS, ESPECIALLY GROUND ROBOTS. THESE LEARNING COMPONENTS WILL PERMIT... view more 

CREDIT: (PHOTO ILLUSTRATION / U.S. ARMY)

ADELPHI, Md. -- Multi-domain operations, the Army's future operating concept, requires autonomous agents with learning components to operate alongside the warfighter. New Army research reduces the unpredictability of current training reinforcement learning policies so that they are more practically applicable to physical systems, especially ground robots.

These learning components will permit autonomous agents to reason and adapt to changing battlefield conditions, said Army researcher Dr. Alec Koppel from the U.S. Army Combat Capabilities Development Command, now known as DEVCOM, Army Research Laboratory.

The underlying adaptation and re-planning mechanism consists of reinforcement learning-based policies. Making these policies efficiently obtainable is critical to making the MDO operating concept a reality, he said.

According to Koppel, policy gradient methods in reinforcement learning are the foundation for scalable algorithms for continuous spaces, but existing techniques cannot incorporate broader decision-making goals such as risk sensitivity, safety constraints, exploration and divergence to a prior.

Designing autonomous behaviors when the relationship between dynamics and goals are complex may be addressed with reinforcement learning, which has gained attention recently for solving previously intractable tasks such as strategy games like go, chess and videogames such as Atari and Starcraft II, Koppel said.

Prevailing practice, unfortunately, demands astronomical sample complexity, such as thousands of years of simulated gameplay, he said. This sample complexity renders many common training mechanisms inapplicable to data-starved settings required by MDO context for the Next-Generation Combat Vehicle, or NGCV.

"To facilitate reinforcement learning for MDO and NGCV, training mechanisms must improve sample efficiency and reliability in continuous spaces," Koppel said. "Through the generalization of existing policy search schemes to general utilities, we take a step towards breaking existing sample efficiency barriers of prevailing practice in reinforcement learning."

Koppel and his research team developed new policy search schemes for general utilities, whose sample complexity is also established. They observed that the resulting policy search schemes reduce the volatility of reward accumulation, yield efficient exploration of an unknown domains and a mechanism for incorporating prior experience.

"This research contributes an augmentation of the classical Policy Gradient Theorem in reinforcement learning," Koppel said. "It presents new policy search schemes for general utilities, whose sample complexity is also established. These innovations are impactful to the U.S. Army through their enabling of reinforcement learning objectives beyond the standard cumulative return, such as risk sensitivity, safety constraints, exploration and divergence to a prior."

Notably, in the context of ground robots, he said, data is costly to acquire.

"Reducing the volatility of reward accumulation, ensuring one explores an unknown domain in an efficient manner, or incorporating prior experience, all contribute towards breaking existing sample efficiency barriers of prevailing practice in reinforcement learning by alleviating the amount of random sampling one requires in order to complete policy optimization," Koppel said.

The future of this research is very bright, and Koppel has dedicated his efforts towards making his findings applicable for innovative technology for Soldiers on the battlefield.

"I am optimistic that reinforcement-learning equipped autonomous robots will be able to assist the warfighter in exploration, reconnaissance and risk assessment on the future battlefield," Koppel said. "That this vision is made a reality is essential to what motivates which research problems I dedicate my efforts."

The next step for this research is to incorporate the broader decision-making goals enabled by general utilities in reinforcement learning into multi-agent settings and investigate how interactive settings between reinforcement learning agents give rise to synergistic and antagonistic reasoning among teams.

According to Koppel, the technology that results from this research will be capable of reasoning under uncertainty in team scenarios.

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This research, conducted in collaboration with Princeton University, University of Alberta and Google Deepmind, was a spotlight talk at NeurIPS 2020, one of the premiere conferences that fosters the exchange of neural information processing systems research in biological, technological, mathematical and theoretical aspects.

College football players underestimate risk of injury and concussion

UNIVERSITY OF COLORADO ANSCHUTZ MEDICAL CAMPUS

Research News

AURORA, Colo. (Dec. 29, 2020) - College football players may underestimate their risk of injury and concussion, according to a new study published today in JAMA Network Open.

Christine Baugh, PhD, MPH, assistant professor of medicine at the University of Colorado School of Medicine and member of the CU Center for Bioethics and Humanities, is the corresponding author of the article, "Accuracy of US College Football Players' Estimates of Their Risk of Concussion or Injury."

Baugh and co-authors report on survey results of 296 college football players from four teams in the Power 5 Conferences of the National Collegiate Athletic Association. Athletes were surveyed in 2017. The researchers found that between 43 percent and 91 percent of respondents underestimated their risk of injury and between 42 percent and 63 percent underestimated their risk of concussion.

To measure the accuracy of football players' risk estimations, the researchers modeled individual athletes' probabilities of sustaining a concussion or injury and compared model estimates to athlete perceptions. While recognizing that many people underestimate health risks, the authors point out that the risks college football athletes face may be more severe or debilitating than those faced by many in the general population. Given this elevated risk profile, they say it is concerning that athletes tend to underestimate the likelihood of these risks. These results raise questions about informed consent and how much risk should be acceptable in the context of a game, Baugh and her co-authors write.

"That athletes underestimated their risk of concussion and injury in this study raises important ethical considerations," Baugh and her colleagues write. "What is the threshold for college athletes to be sufficiently informed of the risks and benefits of football to make decisions that align with their values and preferences?"

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In addition to Baugh, four co-authors are listed. Those authors are affiliated with the University of Washington, the Seattle Children's Research Institute, Boston Children's Hospital, and Harvard Medical School, where Baugh completed a Post-Doctoral Fellowship in Mental Health Policy prior to joining the CU School of Medicine.

About the University of Colorado School of Medicine

Faculty at the University of Colorado School of Medicine work to advance science and improve care. These faculty members include physicians, educators and scientists at UCHealth University of Colorado Hospital, Children's Hospital Colorado, Denver Health, National Jewish Health, and the Veterans Affairs Eastern Colorado Health Care System. The school is located on the Anschutz Medical Campus, one of four campuses in the University of Colorado system.

Story tip from Johns Hopkins expert on Covid-19

JOHNS HOPKINS MEDICINE

Research News

In a study that looked at suicide deaths during 2020's first wave of the COVID-19 pandemic in Maryland, Johns Hopkins Medicine researchers found that, contrary to general predictions of suicides skyrocketing, suicides in the overall population actually dropped, relative to previous years. However, the researchers also discovered that suicide deaths increased dramatically among Black Marylanders during the same period.

The researchers say that their findings, published Dec. 16, 2020, in JAMA Psychiatry, highlight the importance of timely identification of high-risk groups and vulnerable populations to reduce suicide numbers.

Black Americans have been disproportionately affected by the COVID-19 pandemic, underlining long-standing health and social inequities. "Looking at suicide trends by race emphasizes the economic divide we're seeing in America and unfortunately, that divide also is a racial one," says Paul Nestadt, M.D., assistant professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine.

According to Nestadt, the increase in suicides among Black Marylanders -- during the period when COVID-19 deaths peaked and the state was locked down -- could be reflective of a socioeconomic divide. In comparison, he adds, the unexpected decrease in suicides in white Marylanders could be due to greater capacity for remote work or benefit from economic relief efforts.

"I think we're all in this COVID-19 storm together, but not everyone is having the same experience," says Nestadt. "Folks who are in places of economic privilege have been able to continue working more or less remotely, to take time off for themselves, reconnect with family, start a new hobby and so on, but it's a very different story for people working in service industry jobs."

In their study, the researchers looked at suicide deaths from Jan. 1 through July 7, 2020. The data were divided into three periods: a pre-COVID-19 period 1 (Jan. 1 to March 4, 2020); a "progressive closure" (lockdown) period 2 (March 5 to May 7, 2020); and a "progressive reopening" period 3 (May 8 to July 7, 2020). Daily suicide mortality was divided by race and compared with the same periods, from 2017 through 2019.

During period 1, daily suicide mortality did not differ from the same period in 2017 through 2019 for either race, and, in period 3, the rates did not differ for Black residents compared with previous years. However, period 2 daily suicide deaths among Blacks increased by 94% and decreased 45% among whites, compared with the same period in 2017 through2019.

"The implications of our findings are more far-reaching than just suicidology," says Nestadt. "It should help policymakers recognize the importance of things like economic relief and increasing access to equal care, so that there's an end to such disproportionate deaths."

Nestadt says further research is needed to characterize these trends. As continuing pandemic restrictions drive public health priorities, he says, policy interventions and targeted resource allocation are needed to mitigate disparities affecting Black Americans.

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Scientists turned toxic pesticide into treatment against antibiotic-resistant bacteria

Russian scientists from Kaliningrad and St. Petersburg have synthesized nitrogen-containing cyclic compounds that differ only in the relative position of side substituents.

IMMANUEL KANT BALTIC FEDERAL UNIVERSITY

Research News

N-Aryl-C-nitroazoles are an important class of heterocyclic compounds. They are used as pesticides and fungicides. However, these substances could be toxic to humans and cause mutations. As they are not frequently used, there is little data about them in the medicinal chemistry literature. However, it has been suggested recently that the groups of compounds that are traditionally avoided can help to fight pathogenic bacteria. Yet, to reduce toxic effects, a great amount of work must be carried out at the molecular level, accurate optimization of the molecular environment of the nitro-heteroaromatic "warhead". The validity of this approach was demonstrated in the early 2000s through the development of anti-tuberculosis drugs delamanid and pretomanid, currently approved for medical use. They act like prodrugs, that is, the substance itself is inactive, but acquires new properties when it enters the human body.

In terms of this work, scientists from the Baltic Federal University together with colleagues from St. Petersburg State University, the L. Pasteur Research Institute of Epidemiology and Microbiology, and the Research Institute of Phthisiopulmonology in St. Petersburg, are looking for new effective antibacterial drugs, studying various nitrogen heteroaromatic compounds with a nitro group which might be used in medicine further. The compound OTB-021 was found to work well against drug-sensitive strains of tuberculosis pathogens, but was powerless against strains of pathogens that belong to the so-called ESKAPE panel. ESKAPE is an abbreviation for the names of bacterial species most often developing resistance to antibiotics: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter aerogenes. It is a kind of a pun: "eskape" sounds like "escape", and the bacteria of this panel are known to be resistant to most of the known antibiotics, that is, they seem to "escape" from drugs.

To understand how to modify the compound so that it could act on these pathogenic bacteria the scientists constructed two isomeric (identical in the atomic arrangement) series based on OTB-021. Side amino groups changed their position to make the aromatic nitrogen-rich core of the substance more compact, this should reduce the toxicity of the substance. The sensitivity of microorganisms to a new compound was tested via disk diffusion method. Zones of the inhibition of bacterial growth by antibiotic disks and dried solution of the compound in Petri dishes were measured.

It turned out that the ESKAPE bacteria were easily suppressed by the new substances. The minimal concentration of the chemical that prevents the growth of bacteria (μg / ml) for the tested substance shows a result comparable to the use of a ml of the antibiotic ciprofloxacin: for example, 0.3 μg / ml of an antibiotic for Enterococcus acts the same as 2 μg / ml of one of the new substances.

"Starting from the structure of the antimycobacterial OTB-021 which has no activity against ESKAPE pathogens, we developed, synthesized, and tested two isomeric series of novel analogs with an amino group that changes its position in the structure." These compounds can inhibit the growth of all ESKAPE pathogens. Probably, they will help to develop new effective drugs against bacterial diseases which are sometimes very difficult to treat," says Mikhail Krasavin, Doctor of Chemical Science, Professor of the Russian Academy of Sciences, professor and researcher at the Immanuel Kant Baltic Federal University.

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Order and disorder in crystalline ice explained

A new theoretical model enlightens the structure and the electrical properties of pure and doped ice

SCUOLA INTERNAZIONALE SUPERIORE DI STUDI AVANZATI

Research News

 NEWS RELEASE 29-DEC-2020

A fascinating substance with unique properties, ice has intrigued humans since time immemorial. Unlike most other materials, ice at very low temperature is not as ordered as it could be. A collaboration between the Scuola Internazionale Superiore di Studi Avanzati (SISSA), the Abdus Salam International Centre for Theoretical Physics (ICTP), the Institute of Physics Rosario (IFIR-UNR), with the support of the Istituto Officina dei Materiali of the Italian National Research Council (CNR-IOM), made new theoretical inroads on the reasons why this happens and on the way in which some of the missing order can be recovered. In that ordered state the team of scientists have described a relatively obscure and yet fundamental property of very low temperature ice, ferroelectricity. The results, published in PNAS, are likely to extend to ice surfaces, a possibility that could be relevant to the agglomeration of ice particles in interstellar space.

"In an ideally ordered piece of ice the hydrogen atoms of each water molecule should point in the same direction, like soldiers in a platoon looking in front of them," explains Alessandro Laio, physicist of SISSA and ICTP. "If that was the case, ice would exhibit a macroscopic electric polarization ? it would be ferroelectric. Instead, water molecules in ice, even at very low temperature, behave like unruly soldiers, and all look in different directions."

This anomalous behaviour, discovered experimentally in the 1930s, was immediately and famously explained by Linus Pauling: the lack of discipline is an effect of the 'ice rule' constraint ? every oxygen atom should at any moment possess two and only two protons to make it H2O. The difficult kinetics created by that constraint causes the ordering process to become infinitely slow, as in a platoon where each soldier had four neighbours and had to keep two hands on the shoulders of two of them.

"Were it not for impurities or defects, which turned out to play a revealing role, one would still today not know whether proton order and ferroelectricity of bulk crystalline ice is a real possibility or a figment of the imagination, since neither experiments nor simulations could overcome the ice rule-generated kinetic slowdown," points out Erio Tosatti, physicist of SISSA, ICTP and CNR-IOM Democritos.

Impurities, such as one KOH replacing H2O, are in fact known to allow the ordering process to nucleate and ice to turn ordered and ferroelectric at very low temperature, although only partly and sluggishly. Once again, the 'ice rule' was suspected to be behind the sluggishness of this process, but exactly how that worked was not really known.

Together with Jorge Lasave and Sergio Koval of the IFIR-UNR in Argentina, both of them ICTP associate members, Alessandro Laio and Erio Tosatti designed a theoretical model and a strategy to explain the behaviour of both pure and doped ice.

"According to this model," the scientists explain, "once an impurity is introduced inside an initial non-equilibrium low temperature disordered state, it acts as a seed for the ordered phase, but in a peculiar manner: not all the 'soldiers' around the impurity start looking in the correct direction, but only those in front or behind the impurity. Thus, at the end of the process only a string of soldiers inside the platoon will become ordered." This highly atypical process has many of the characteristics that can explain the sluggish and incomplete onset of ferroelectric order in real doped ice.

"Although the study is restricted for now to bulk ice," Tosatti and Laio conclude, "the mechanism highlighted is likely to extend to ice surfaces, where strings of ordered protons could nucleate at low temperatures, explaining a long known small amount of local ferroelectric polarization, a phenomenon also mentioned as possibly relevant to the agglomeration of ice particles in interstellar space."

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Imaging the twilight zone

General anesthesia and normal sleep affect brain in an amazingly similar way as consciousness fades

UNIVERSITY OF TURKU

Research News

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IMAGE: DIFFERENCES IN BRAIN ACTIVITY BETWEEN CONNECTED AND DISCONNECTED STATES OF CONSCIOUSNESS STUDIED WITH POSITRON EMISSION TOMOGRAPHY (PET) IMAGING. ACTIVITY OF THE THALAMUS, ANTERIOR (ACC) AND POSTERIOR CINGULATE CORTICES (PCC), AND... view more 

CREDIT: UNIVERSITY OF TURKU

What happens in the brain when our conscious awareness fades during general anesthesia and normal sleep? Finnish scientists studied this question with novel experimental designs and functional brain imaging. They succeeded in separating the specific changes related to consciousness from the more widespread overall effects, and discovered that the effects of anesthesia and sleep on brain activity were surprisingly similar. These novel findings point to a common central core brain network fundamental for human consciousness.

Explaining the biological basis of human consciousness is one of the greatest challenges of science. While the loss and return of consciousness, as regulated by drugs or physiological sleep, have been employed as model systems in the study of human consciousness, previous research results have been confounded by many experimental simplifications.

"One major challenge has been to design a set-up, where brain data in different states differ only in respect to consciousness. Our study overcomes many previous confounders, and for the first time, reveals the neural mechanisms underlying connected consciousness," says Harry Scheinin, Docent of Pharmacology, Anesthesiologist, and the Principal Investigator of the study from the University of Turku, Finland.

A new and innovative experimental set-up

Brain activity was measured with positron emission tomography (PET) imaging during different states of consciousness in two separate experiments in the same group of healthy subjects. Measurements were made during wakefulness, escalating and constant levels of two anesthetic agents, and during sleep-deprived wakefulness and Non-Rapid Eye Movement (NREM) sleep.

In the first experiment, the subjects were randomly allocated to receive either propofol or dexmedetomidine (two anesthetic agents with different molecular mechanisms of action) at stepwise increments until the subjects no longer responded. In the sleep study, they were allowed to fall asleep naturally. In both experiments, the subjects were roused to achieve rapid recovery to a responsive state, followed by immediate and detailed interviews of subjective experiences from the preceding unresponsive period. Unresponsive anesthetic states and verified NREM sleep stages, where a subsequent report of mental content included no signs of awareness of the surrounding world, indicated a disconnected state in the study participants. Importantly, the drug dosing in the first experiment was not changed before or during the shift in the behavioral state of the subjects.

"This unique experimental design was the key idea of our study and enabled us to distinguish the changes that were specific to the state of consciousness from the overall effects of anesthesia," explains Annalotta Scheinin, Anesthesiologist, Doctoral Candidate and the first author of the paper.

Researchers discovered a common central core brain network

When PET images of responsive and connected brains were compared with those of unresponsive and disconnected, the scientists found that activity of the thalamus, cingulate cortices and angular gyri were affected independently of the used anesthetic agent, drug concentration and direction of change in the state of consciousness (see figure). Strikingly analogous findings were obtained when physiological sleep was compared with sleep-deprived wakefulness. Brain activity changes were much more extensive when the disconnected states were compared with a fully awake state. State-specific findings were thus distinct and separable from the overall effects of drug-induced anesthesia and natural sleep, which included widespread suppression of brain activity across cortical areas.

These findings identify a central core brain network that is fundamental for human consciousness.

"General anesthesia seems to resemble normal sleep more than has traditionally been thought. This interpretation is, however, well in line with our recent electrophysiological findings in another anesthesia study," says Harry Scheinin.

Subjective experiences are common during general anesthesia

Interestingly, unresponsiveness rarely denoted unconsciousness (i.e., total absence of subjective experiences), as most participants reported internally generated experiences, such as dreams, in the interviews. This is not an entirely new finding as dreams are commonly reported by patients after general anesthesia.

"However, because of the minimal delay between the awakenings and the interviews, the current results add significantly to our understanding of the nature of the anesthetic state. Against a common belief, full loss of consciousness is not needed for successful general anesthesia, as it is sufficient to just disconnect the patient's experiences from what is going on in the operating room," explains Annalotta Scheinin.

The new study sheds light on the fundamental nature of human consciousness and brings new information on brain functions in intermediate states between wakefulness and complete unconsciousness. These findings may also challenge our current understanding of the essence of general anesthesia.

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The experiments were carried out at Turku PET Centre as a joint effort of the research groups of Harry Scheinin studying anesthesia mechanisms, and Professor of Psychology Antti Revonsuo studying human consciousness and the brain from the point of view of philosophy and psychology, in collaboration with Professor Michael Alkire from the University of California, Irvine, USA. Turku PET Centre is a Finnish National Research Institute established by University of Turku, Åbo Akademi University and Turku University Hospital. The study was funded by the Academy of Finland and the Jane and Aatos Erkko Foundation.


Primordial black holes and the search for dark matter from the multiverse

KAVLI INSTITUTE FOR THE PHYSICS AND MATHEMATICS OF THE UNIVERSE

Research News

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IMAGE: BABY UNIVERSES BRANCHING OFF OF OUR UNIVERSE SHORTLY AFTER THE BIG BANG APPEAR TO US AS BLACK HOLES. view more 

CREDIT: KAVLI IPMU

The Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) is home to many interdisciplinary projects which benefit from the synergy of a wide range of expertise available at the institute. One such project is the study of black holes that could have formed in the early universe, before stars and galaxies were born.

Such primordial black holes (PBHs) could account for all or part of dark matter, be responsible for some of the observed gravitational waves signals, and seed supermassive black holes found in the center of our Galaxy and other galaxies. They could also play a role in the synthesis of heavy elements when they collide with neutron stars and destroy them, releasing neutron-rich material. In particular, there is an exciting possibility that the mysterious dark matter, which accounts for most of the matter in the universe, is composed of primordial black holes. The 2020 Nobel Prize in physics was awarded to a theorist, Roger Penrose, and two astronomers, Reinhard Genzel and Andrea Ghez, for their discoveries that confirmed the existence of black holes. Since black holes are known to exist in nature, they make a very appealing candidate for dark matter.

The recent progress in fundamental theory, astrophysics, and astronomical observations in search of PBHs has been made by an international team of particle physicists, cosmologists and astronomers, including Kavli IPMU members Alexander Kusenko, Misao Sasaki, Sunao Sugiyama, Masahiro Takada and Volodymyr Takhistov.

To learn more about primordial black holes, the research team looked at the early universe for clues. The early universe was so dense that any positive density fluctuation of more than 50 percent would create a black hole. However, cosmological perturbations that seeded galaxies are known to be much smaller. Nevertheless, a number of processes in the early universe could have created the right conditions for the black holes to form.

One exciting possibility is that primordial black holes could form from the "baby universes" created during inflation, a period of rapid expansion that is believed to be responsible for seeding the structures we observe today, such as galaxies and clusters of galaxies. During inflation, baby universes can branch off of our universe. A small baby (or "daughter") universe would eventually collapse, but the large amount of energy released in the small volume causes a black hole to form.

An even more peculiar fate awaits a bigger baby universe. If it is bigger than some critical size, Einstein's theory of gravity allows the baby universe to exist in a state that appears different to an observer on the inside and the outside. An internal observer sees it as an expanding universe, while an outside observer (such as us) sees it as a black hole. In either case, the big and the small baby universes are seen by us as primordial black holes, which conceal the underlying structure of multiple universes behind their "event horizons." The event horizon is a boundary below which everything, even light, is trapped and cannot escape the black hole.

CAPTION

Hyper Suprime-Cam (HSC) is a gigantic digital camera on the Subaru Telescope

In their paper, the team described a novel scenario for PBH formation and showed that the black holes from the "multiverse" scenario can be found using the Hyper Suprime-Cam (HSC) of the 8.2m Subaru Telescope, a gigantic digital camera--the management of which Kavli IPMU has played a crucial role--near the 4,200 meter summit of Mt. Mauna Kea in Hawaii. Their work is an exciting extension of the HSC search of PBH that Masahiro Takada, a Principal Investigator at the Kavli IPMU, and his team are pursuing. The HSC team has recently reported leading constraints on the existence of PBHs in Niikura, Takada et. al. (Nature Astronomy 3, 524-534 (2019))

Why was the HSC indispensable in this research? The HSC has a unique capability to image the entire Andromeda galaxy every few minutes. If a black hole passes through the line of sight to one of the stars, the black hole's gravity bends the light rays and makes the star appear brighter than before for a short period of time. The duration of the star's brightening tells the astronomers the mass of the black hole. With HSC observations, one can simultaneously observe one hundred million stars, casting a wide net for primordial black holes that may be crossing one of the lines of sight.

The first HSC observations have already reported a very intriguing candidate event consistent with a PBH from the "multiverse," with a black hole mass comparable to the mass of the Moon. Encouraged by this first sign, and guided by the new theoretical understanding, the team is conducting a new round of observations to extend the search and to provide a definitive test of whether PBHs from the multiverse scenario can account for all dark matter.


CAPTION

A star in the Andromeda galaxy temporarily becomes brighter if a primordial black hole passes in front of the star, focusing its light in accordance with the theory of gravity.

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Paper details
Journal: Physical Review Letters
Title: Exploring Primordial Black Holes from the Multiverse with Optical Telescopes
Authors: Alexander Kusenko (1, 2), Misao Sasaki (2, 3, 4), Sunao Sugiyama (2, 5), Masahiro Takada (2), Volodymyr Takhistov (1,2), and Edoardo Vitagliano (1)

Author affiliation:
1. Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095-1547, USA
2. Kavli Institute for the Physics and Mathematics of the Universe (WPI), UTIAS The University of Tokyo, Kashiwa, Chiba 277-8583, Japan
3. Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan
4. Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, Taipei 10617, Taiwan
5. Department of Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan

DOI: https://doi.org/10.1103/PhysRevLett.125.181304 (October 30, 2020)
Abstract of the paper: (Physical Review Letters)
Preprint: (arXiv.org page)

Related links:
Kavli IPMU: Primordial black holes and the search for dark matter from the multiverse

Patient Characteristics Associated With Telemedicine Access for Primary and Specialty Ambulatory Care During the COVID-19 Pandemic

Key Points

Question  What sociodemographic factors are associated with higher use of telemedicine and the use of video (vs telephone) for telemedicine visits for ambulatory care during the coronavirus disease 2019 (COVID-19) pandemic?

Findings  In this cohort study of 148 402 patients scheduled for primary care and medical specialty ambulatory telemedicine visits at a large academic health system during the early phase of the COVID-19 pandemic, older age, Asian race, non-English language as the patient’s preferred language, and Medicaid were independently associated with fewer completed telemedicine visits. Older age, female sex, Black race, Latinx ethnicity, and lower household income were associated with lower use of video for telemedicine care.

Meaning  This study identified racial/ethnic, sex, age, language, and socioeconomic differences in accessing telemedicine for primary care and specialty ambulatory care; if not addressed, these differences may compound existing inequities in care among vulnerable populations.

Abstract

Importance  The coronavirus disease 2019 (COVID-19) pandemic has required a shift in health care delivery platforms, necessitating a new reliance on telemedicine.

Objective  To evaluate whether inequities are present in telemedicine use and video visit use for telemedicine visits during the COVID-19 pandemic.

Design, Setting, and Participants  In this cohort study, a retrospective medical record review was conducted from March 16 to May 11, 2020, of all patients scheduled for telemedicine visits in primary care and specialty ambulatory clinics at a large academic health system. Age, race/ethnicity, sex, language, median household income, and insurance type were all identified from the electronic medical record.

Main Outcomes and Measures  A successfully completed telemedicine visit and video (vs telephone) visit for a telemedicine encounter. Multivariable models were used to assess the association between sociodemographic factors, including sex, race/ethnicity, socioeconomic status, and language, and the use of telemedicine visits, as well as video use specifically.

Results  A total of 148 402 unique patients (86 055 women [58.0%]; mean [SD] age, 56.5 [17.7] years) had scheduled telemedicine visits during the study period; 80 780 patients (54.4%) completed visits. Of 78 539 patients with completed visits in which visit modality was specified, 35 824 (45.6%) were conducted via video, whereas 24 025 (56.9%) had a telephone visit. In multivariable models, older age (adjusted odds ratio [aOR], 0.85 [95% CI, 0.83-0.88] for those aged 55-64 years; aOR, 0.75 [95% CI, 0.72-0.78] for those aged 65-74 years; aOR, 0.67 [95% CI, 0.64-0.70] for those aged ≥75 years), Asian race (aOR, 0.69 [95% CI, 0.66-0.73]), non-English language as the patient’s preferred language (aOR, 0.84 [95% CI, 0.78-0.90]), and Medicaid insurance (aOR, 0.93 [95% CI, 0.89-0.97]) were independently associated with fewer completed telemedicine visits. Older age (aOR, 0.79 [95% CI, 0.76-0.82] for those aged 55-64 years; aOR, 0.78 [95% CI, 0.74-0.83] for those aged 65-74 years; aOR, 0.49 [95% CI, 0.46-0.53] for those aged ≥75 years), female sex (aOR, 0.92 [95% CI, 0.90-0.95]), Black race (aOR, 0.65 [95% CI, 0.62-0.68]), Latinx ethnicity (aOR, 0.90 [95% CI, 0.83-0.97]), and lower household income (aOR, 0.57 [95% CI, 0.54-0.60] for income <$50 000; aOR, 0.89 [95% CI, 0.85-0.92], for $50 000-$100 000) were associated with less video use for telemedicine visits. These results were similar across medical specialties.

Conclusions and Relevance  In this cohort study of patients scheduled for primary care and medical specialty ambulatory telemedicine visits at a large academic health system during the early phase of the COVID-19 pandemic, older patients, Asian patients, and non–English-speaking patients had lower rates of telemedicine use, while older patients, female patients, Black, Latinx, and poorer patients had less video use. Inequities in accessing telemedicine care are present, which warrant further attention.

READ OR DOWNLOAD THE STUDY HERE:

Patient Characteristics Associated With Telemedicine Access for Primary and Specialty Ambulatory Care During the COVID-19 Pandemic | Global Health | JAMA Network Open | JAMA Network


Study examines the most effective COVID-19 control policies

UNIVERSITY OF TORONTO, ROTMAN SCHOOL OF MANAGEMENT

Research News

 NEWS RELEASE 

IMAGE

IMAGE: ANITA M. MCGAHAN IS A UNIVERSITY PROFESSOR AND THE GEORGE E. CONNELL CHAIR IN ORGANIZATIONS & SOCIETY AT THE UNIVERSITY OF TORONTO'S ROTMAN SCHOOL OF MANAGEMENT AND MUNK SCHOOL OF... view more 

CREDIT: ROTMAN SCHOOL OF MANAGEMENT

Toronto - With the arrival of effective vaccines for the COVID-19 virus, the end of the pandemic is on the horizon but in the short term the virus continues to spread.

A timely new study published today by PLOS ONE examines the effectiveness of COVID-19 control policies in 40 jurisdictions including countries and U.S. states.

Among the conclusions is that significant social costs must be incurred to reduce the growth of the virus below zero. In most jurisdictions examined, policies with a lesser social impact including cancellation of public events, restrictions of gatherings to fewer than 100 people, and recommendations to stay at home, are not enough in themselves to control COVID-19. Socially intolerable measures such as stay-at-home orders, targeted or full workplace and school closings are also required.

The study is authored by Anita M. McGahan, University Professor and the George E. Connell Chair in Organizations & Society at the University of Toronto's Rotman School of Management and Munk School of Global Affairs and Public Policy, Wesley Wu-Yi Koo, an assistant professor of strategy at INSEAD, and Phebo Wibbens, an assistant professor of strategy at INSEAD.

The study used a model to generate estimates of the marginal impact of each policy in a jurisdiction after accounting for the overall portfolio of policies adopted by the jurisdiction, the levels at which the policies are implemented, the rigorousness of compliance within the jurisdiction, the jurisdiction's COVID-19 infections, COVID-19 deaths, and excess deaths, and the performance of the portfolio of policies in other jurisdictions. Eleven categories of COVID-19 control policies were examined including school closings, workplace closings, cancellation of public events, restrictions on gatherings, closing of public transport, stay-at-home requirements, restrictions on internal movement, international travel controls, public information campaigns, testing, and contact tracing.

The study is online at https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0244177.

The Rotman School of Management is part of the University of Toronto, a global centre of research and teaching excellence at the heart of Canada's commercial capital. Rotman is a catalyst for transformative learning, insights, and public engagement, bringing together diverse views and initiatives around a defining purpose: to create value for business and society. For more information, visit http://www.rotman.utoronto.ca.

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Casting a light: Coronavirus transmission and natural UV light

BY TIM SANDLE DEC 28, 2020 IN SCIENCE

New research, centered upon seasonal variations, finds that natural variations in ultraviolet radiation can influence the ease of transmission of the SARS-CoV-2 virus and rates of COVID-19

The model that the research is based upon finds that the incidence of coronavirus transmission is linked to a seasonal pattern, in terms of transmission occurring faster in the winter than in the summer. While there are different reasons why a virus might spread more rapidly in the winter (something that mirrors influenza spread), the levels of darkness appear to be a contributing factor.

Harvard University researchers have drawn this inference by examining weather patterns from some 3,000 administrative regions located in more than 170 countries. Crunching these data, it was revealed that the spread of the SARS-CoV-2 virus through a given population tended to be lower in the weeks following higher ultraviolet light exposure.

This association appears to tally with some emerging studies that show how UV light, when applied to a surface, can inactivate coronaviruses. The sensitivity of the UV appears to be a key factor, with the wavelength 267 nm ~ 279 nm being optimal. As well as surface treatment, the application of UV-C light to ventilation systems, and water systems in hospitals, is being explored.

Inactivation by UV
could occur via several mechanisms, among them damage to nucleic acids, proteins, or internal production of oxygen radicals.

The
researchers found that changes in UV between winter and summer resulted in a 7-percentage point decrease in the coronavirus transmission rate within the Northern Hemisphere. However, it remains that the complete seasonality of COVID-19 remains unclear and further research is required. This is due to the uncertain role of other variables, like temperature and humidity.

Importantly, while seasonal changes in UV appear to alter the spread of COVID-19 this is not as much as achieved by social distancing. As seen during the summer, coronavirus infections still remain high in crowded places and especially in relation to indoor environments. Therefore, standard COVID-19 avoidance measures should continue to be practiced.

The research findings have been published in the journal Proceedings of the National Academy of Sciences. The research paper is titled "Global evidence for ultraviolet radiation decreasing COVID-19 growth rates."

Read more: http://www.digitaljournal.com/tech-and-science/science/casting-a-light-coronavirus-transmission-and-natural-uv-light/article/583137#ixzz6i5pt56mz