Tuesday, March 31, 2020

Study Shows Photos of Empty Supermarket Shelves Instigate Panic Buying


Research from University of Edinburgh Business School and the University of Southampton has found that photographs of empty supermarket shelves in news stories about panic buying instigate people to follow the buying frenzy.

The study, which analysed responses from 230 British adults*, found that those exposed to images of empty supermarket shelves were more likely to panic buy. A news story accompanied by an image of empty shelves saw an increase of 86% in of the amount of people who said this would make them want to panic buy, compared to if they saw an image of full shelves. In addition, 33% of participants in the study admitted to stockpiling supplies.

Images of empty shelves can prompt people to panic buy.
Image by John Cameron on Unsplash.



As part of the research, respondents were shown fictional news items accompanied by either images of empty supermarket shelves or full shelves. They were then asked to record their level of panic and intention to stockpile, amongst other variables.

In addition, the study also asked the participants to rate how likely they were to click on one of the fictional articles if the headline was accompanied by a picture of empty shelves. The articles with empty shelves received 36% more clicks compared to full shelves.

Dr Rob Angell, Associate Professor in Marketing Research from University of Southampton, said: “When the imagery shows an empty shelf, people are drawn to the fact that others have already acted and that they are potentially behind the curve. This ends up negating positive and pro-social messages in the article itself. If a picture is worth 1000 words, then getting it right, at a time of such importance, is absolutely necessary.”

Dr Ben Marder, Senior Lecturer in Marketing at University of Edinburgh Business School, said: “In these uncertain times with the coronavirus outbreak affecting all our lives, using images of empty shelves is a critical mistake in trying to calm panic buying. As such, we urge news and government communications to be extremely cautious. It is important to be aware that with a picture of full shelves the message that there was no need to panic buy succeeded.

“In addition, the fact that news articles receive more clicks if they used images of empty shelves, shows that measuring the success of stories by the number of clicks can detract from the media’s ability to convey important social messages.”

*The study was carried out between 15 and 16 March among 230 adults residing in the UK. This was a joint project by University of Edinburgh Business School and the University of Southampton.

 


Contacts and sources:
Dr Rob Angell BA(Hons), MSc, PhD Associate Professor in Marketing Research
University of Southampton








UK Testing Inhaled Drug That Could Prevent Worsening of COVID19



Southampton researchers are trialling an inhaled drug that could prevent worsening of COVID19 in those most at risk.

On the 18th March Synairgen announced its plans to initiate a pilot clinical trial of SNG001 in COVID-19 patients. The trial will provide data on the efficacy of inhaled interferon beta in the treatment of ambulatory and hospitalised patients infected with SARS-CoV-2. Since the announcement, we have received a number of requests for SNG001 supplies to treat individuals outside the trial. As SNG001 is an experimental drug, untested as to safety and efficacy in this patient group, we regret that we are unable to fulfil any such request at this time. Synairgen’s team is working very hard to establish these measures in a well-controlled environment as quickly as possible.

The trial, led by Tom Wilkinson, Professor of Respiratory Medicince in the Faculty of Medicine and a consultant in respiratory medicine at University Hospital Southampton, will involve 100 patients at Southampton and up to ten other NHS hospitals taking part.

Those patients will receive the best current COVID19 care, whilst inhaling either a placebo or SNG001, a special formulation of the naturally occurring antiviral protein interferon beta 1a (IFN-β), for 14 days.

Credit: University of Southampton

The trial will be undertaken with Synairgen, a drug development company founded by University of Southampton Professors Stephen Holgate, Donna Davies and Ratko Djukanovic.

SNG001 has been developed to prevent severe lower respiratory tract illness caused by cold and flu infections when they spread to the lungs.

Phase II clinical trials in asthmatic patients have previously shown that SNG001 is well tolerated, enhances the lungs’ antiviral defences and improves lung function during cold or flu infection.

The Southampton researchers have shown that key high risk groups for COVID-19, including older people and those with some chronic diseases have lower levels of IFN-β, a natural antiviral produced in all our lungs during viral lung infections.

SNG001 delivers extra IFN-β direct to the lungs, correcting this deficiency and counteracting viral strategies to evade the host’s immune defences by inhibiting natural IFN-β production.

Professor Wilkinson said, “COVID19 cis presenting a major challenge to vulnerable patients, the health service and wider society whilst a vaccine will be key, that could some time away. Right now we need effective frontline treatments to give doctors the tools to treat the most vulnerable and to help patients recover quickly as the pressure on health systems mounts."

Responding to the urgency of the pandemic, Synairgen and Professor Wilkinson worked with regulators and Southampton’s R&D department to open the study within weeks.

“We have worked intensively with the relevant authorities and collaborators to enable SNG001 to be assessed in COVID-19 patients. A successful outcome from this trial in COVID-19 patients would be a major breakthrough in the fight against this coronavirus pandemic.” Said Richard Marsden CEO of Synairgen.

Study measures will include World Health Organisation recommended assessments of illness severity, and treatment intensity measures alongside standard assessments of safety.

Positive initial results from the 100 patient pilot phase could see the trial expanded to more hospitals, with Synairgen increasing production of th

e drug in parallel.

“Having the trial adopted by the NIHR Respiratory Translational Research Collaboration, is key to taking any positive findings forward as part of their efforts to accelerate discovery and development for COVID-19 and I am indebted to the support my collaborators are giving to get this study started.” added Professor Wilkinson.





Contacts and sources:
University of Southampton
















Study: Using Copper To Prevent The Spread Of Respiratory Viruses



New research from the University of Southampton has found that copper can effectively help to prevent the spread of respiratory viruses, which are linked to severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).

Animal coronaviruses that 'host jump' to humans, such as SARS and MERS, result in severe infections with high mortality. The Southampton researchers found that a closely-related human coronavirus - 229E - can remain infectious on common surface materials for several days, but is rapidly destroyed on copper.

This scanning electron microscope image shows SARS-CoV-2 (yellow)—also known as 2019-nCoV, the virus that causes COVID-19—isolated from a patient in the U.S., emerging from the surface of cells (blue/pink) cultured in the lab.
Credit: NIAID-RML

A newly-published paper in mBio - a journal of the American Society for Microbiology - reports that human coronavirus 229E, which produces a range of respiratory symptoms from the common cold to more lethal outcomes such as pneumonia, can survive on surface materials including ceramic tiles, glass, rubber and stainless steel for at least five days. While human-to-human transmission is important, infections can be contracted by touching surfaces contaminated by respiratory droplets from infected individuals, or hand touching, leading to a wider and more rapid spread

On copper, and a range of copper alloys - collectively termed 'antimicrobial copper' - the coronavirus was rapidly inactivated (within a few minutes, for simulated fingertip contamination). Exposure to copper destroyed the virus completely and irreversibly, leading the researchers to conclude that antimicrobial copper surfaces could be employed in communal areas and at any mass gatherings to help reduce the spread of respiratory viruses and protect public health.

Lead researcher Dr Sarah Warnes said: "Transmission of infectious diseases via contaminated surfaces is far more important than was originally thought, and this includes viruses that cause respiratory infections. This is especially important when the infectious dose is low and just a few virus particles can initiate an infection.

"Human coronavirus, which also has ancestral links with bat-like viruses responsible for SARS and MERS, was found to be permanently and rapidly deactivated upon contact with copper. What's more, the viral genome and structure of the viral particles were destroyed, so nothing remained that could pass on an infection. With the lack of antiviral treatments, copper offers a measure that can help reduce the risk of these infections spreading."

Speaking on the importance of the study, Professor Bill Keevil, co-author and Chair in Environmental Healthcare at the University of Southampton, said: "Respiratory viruses are responsible for more deaths, globally, than any other infectious agent. The evolution of new respiratory viruses, and the re-emergence of historic virulent strains, poses a significant threat to human health.

"The rapid inactivation and irreversible destruction of the virus observed on copper and copper alloy surfaces suggests that the incorporation of copper alloy surfaces - in conjunction with effective cleaning regimes and good clinical practice - could help control transmission of these viruses."

Previous research by Professor Keevil and Dr Warnes has proved copper's efficacy against norovirus, influenza and hospital superbugs, such as MRSA and Klebsiella, plus stopping the transfer of antibiotic resistance genes to other bacteria to create new superbugs.

For more information on antimicrobial copper, visit
http://www.antimicrobialcopper.org



Contacts and sources:
University of Southampton


Publication: Human coronavirus 229E remains infectious on common touch surface materials S. L. Warnes, Z. R. Little and C. W. Keevil. . mBio, November 2015 DOI: 10.1128/mBio.01697-15





Could The Right Dose Of Geoengineering Reduce Climate Change Risks?



Injecting the right dose of sulphur dioxide into Earth’s upper atmosphere to thicken the layer of light reflecting aerosol particles artificially could reduce the effects of climate change overall, according to UCL and Harvard researchers.


Credit: Earth Observations taken by the Expedition 13 crew, credit: NASA

Stratospheric aerosol geoengineering is the idea that adding a layer of aerosol particles to the upper atmosphere can reduce climate changes caused by greenhouse gases such as carbon dioxide.

Previous research shows that solar geoengineering could be achieved using commercially available aircraft technologies to deliver the particles at a cost of a few billion dollars per year and would reduce global average temperatures. However, the question remains whether this approach could reduce important climate hazards at a regional level. That is, could it reduce region-by-region changes in water availability or extreme temperatures?

Results from a new study by UCL and Harvard researchers suggest that even a crude method like injecting sulphur dioxide in the stratosphere could reduce many important climate hazards without making any region obviously worse off.

The findings, published today in Environmental Research Letters, used results from a sophisticated simulation of stratospheric aerosol geoengineering to evaluate whether the approach could offset or worsen the effects of climate change around the world. How these effects differed under different temperature scenarios was also tested.

The team found that halving warming by adding aerosols to the stratosphere could moderate important climate hazards in almost all regions. They saw an exacerbation of the effects of climate change in only a very small fraction of land areas.

Lead author, Professor Peter Irvine (UCL Earth Sciences), said: “Most studies focus on a scenario where solar geoengineering offsets all future warming. While this reduces overall climate change substantially, we show that in these simulations, it goes too far in some respects leading to about 9% of the land area experiencing greater climate change, i.e. seeing the effects of climate change exacerbated.

“However, if instead only half the warming is offset, then we find that stratospheric aerosol geoengineering could still reduce climate change overall but would only exacerbate change over 1.3% of the land area.”

The team emphasize that solar geoengineering only treats the symptoms of climate change and not the underlying cause, which is the build-up of CO2 and other greenhouse gases in the atmosphere. It should therefore be considered as a complementary approach to emissions cuts as a way to address climate change.

The study is a follow-up to a paper published last year in Nature Climate Change* showed similar results when solar geoengineering was approximated by simply turning down the sun. That prior study begged the question: would the results hold up with a more realistic simulation using injection of sulphur dioxide, the simplest known method of solar geoengineering.

“Our results suggest that when used at the right dose and alongside reductions in greenhouse gas emissions, stratospheric aerosol geoengineering could be useful for managing the impacts of climate change. However, there are still many uncertainties about the potential effects of stratospheric aerosol geoengineering and more research is needed to know if this idea is truly viable,” added Dr Irvine.

The team used data from the Geoengineering Large Ensemble Study, which used a sophisticated climate-chemistry model to simulate the climate response to a hypothetical deployment of stratospheric aerosol geoengineering. In this model study, sulphur dioxide was released at different latitudes in the Tropics to produce a layer of aerosols tuned to keep temperatures steady under an extreme global warming scenario.

The researchers focused on changes in mean and extreme temperature, changes in water availability and changes in extreme precipitation, i.e. climate variables that determine key climate risks.

Previous work suggested that stratospheric aerosol geoengineering could lead to a substantial weakening of monsoons and an intensification of drought. However, the authors found that in those regions where halving warming with stratospheric aerosol geoengineering exacerbated change, it increased water availability rather than reduced it. This suggests that concerns that stratospheric aerosol geoengineering could lead to aridification and drought could be misplaced.

Co-author, Professor David Keith (Harvard’s Engineering and Applied Sciences and Kennedy school), said: “Early research with climate models consistently shows that spatially uniform solar radiation modification could significantly reduce climate risks when combined with emissions cuts. But, should we trust the models? Uncertainties are deep and no single result is trustworthy, but this paper is a step towards more realistic modelling from injection to regional impacts.”

The team are now researching the projected effects of stratospheric aerosol geoengineering on the water cycle in more depth to try to understand the potential benefits and risks to society and ecosystems.





Contacts and sources:
Bex Caygill 

Surgical Masks As Good As Respirators For Flu And Respiratory Virus Protection



Researchers may finally have an answer in the long-running controversy over whether the common surgical mask is as effective as more expensive respirator-type masks in protecting health care workers from flu and other respiratory viruses.

A study published today in JAMA compared the ubiquitous surgical (or medical) mask, which costs about a dime, to a less commonly used respirator called an N95, which costs around $1. The study reported “no significant difference in the effectiveness” of medical masks vs. N95 respirators for prevention of influenza or other viral respiratory illness.
Credit: UT Southwestern Medical Center

“This study showed there is no difference in incidence of viral respiratory transmission among health care workers wearing the two types of protection,” said Dr. Trish Perl, Chief of UT Southwestern’s Division of Infectious Diseases and Geographic Medicine and the report’s senior author. “This finding is important from a public policy standpoint because it informs about what should be recommended and what kind of protective apparel should be kept available for outbreaks.”

Medical personnel – in particular nurses, doctors, and others with direct patient contact – are at risk when treating patients with contagious diseases such as influenza (flu). A large study conducted in a New York hospital system after the 2009 outbreak of H1N1, or swine flu, found almost 30 percent of health care workers in emergency departments contracted the disease themselves, Dr. Perl said.

During that pandemic, the U.S. Centers for Disease Control and Prevention (CDC) recommended using the tighter-fitting N95 respirators, designed to fit closely over the nose and mouth and filter at least 95 percent of airborne particles, rather than the looser-fitting surgical masks routinely worn by health care workers, Dr. Perl said. But some facilities had trouble replenishing N95s as supplies were used.

In addition, there are concerns health care workers might be less vigilant about wearing the N95 respirators since many perceive them to be less comfortable than medical masks, such as making it harder to breathe and being warmer on the wearer’s face.

Earlier clinical studies comparing the masks and respirators yielded mixed results, said Dr. Perl, also a Professor of Internal Medicine who holds the Jay P. Sanford Professorship in Infectious Diseases.

The new study was performed at multiple medical settings in seven cities around the country, including Houston, Denver, Washington, and New York, by researchers at the University of Texas, the CDC, Johns Hopkins University, the University of Colorado, Children’s Hospital Colorado, the University of Massachusetts, the University of Florida, and several Department of Veterans Affairs hospitals. Researchers collected data during four flu seasons between 2011 and 2015, examining the incidence of flu and acute respiratory illnesses in the almost 2,400 health care workers who completed the study.

The project was funded by the CDC, the Veterans Health Administration, and the Biomedical Advanced Research and Development Authority (BARDA), which is part of the U.S. Health and Human Services Department and was founded in the years after Sept. 11, 2001, to help secure the nation against biological and other threats.

Dr. Trish Perl

Credit: UT Southwestern Medical Center

“It was a huge and important study – the largest ever done on this issue in North America,” Dr. Perl said.

In the end, 207 laboratory-confirmed influenza infections occurred in the N95 groups versus 193 among medical mask wearers, according to the report. In addition, there were 2,734 cases of influenza-like symptoms, laboratory-confirmed respiratory illnesses, and acute or laboratory-detected respiratory infections (where the worker may not have felt ill) in the N95 groups, compared with 3,039 such events among medical mask wearers.

“The takeaway is that this study shows one type of protective equipment is not superior to the other,” she said. “Facilities have several options to provide protection to their staff – which include surgical masks – and can feel that staff are protected from seasonal influenza. Our study supports that in the outpatient setting there was no difference between the tested protections.”

Dr. Perl said she expects more studies to arise from the data collected in this report; she now plans to investigate the dynamics of virus transmission to better understand how respiratory viruses are spread.


Contacts and sources:
Carol Marie Cropper
UT Southwestern Medical Center

Publication: N95 Respirators vs Medical Masks for Preventing Influenza Among Health Care Personnel. Lewis J. Radonovich, Michael S. Simberkoff, Mary T. Bessesen, Alexandria C. Brown, Derek A. T. Cummings, Charlotte A. Gaydos, Jenna G. Los, Amanda E. Krosche, Cynthia L. Gibert, Geoffrey J. Gorse, Ann-Christine Nyquist, Nicholas G. Reich, Maria C. Rodriguez-Barradas, Connie Savor Price, Trish M. Perl. JAMA, 2019; 322 (9): 824 DOI: 10.1001/jama.2019.11645




T-Ray Device Transforms Wi-Fi Signals To Electricity, Could Enable Self-Powering Cellphones, Implants, Portable Electronics

A device for harnessing terahertz radiation might enable self-powering implants, cellphones, other portable electronics.

Terahertz waves are pervasive in our daily lives, and if harnessed, their concentrated power could potentially serve as an alternate energy source. Imagine, for instance, a cellphone add-on that passively soaks up ambient T-rays and uses their energy to charge your phone.
Terahertz waves are pervasive in our daily lives, and if harnessed, their concentrated power could potentially serve as an alternate energy source. Imagine, for instance, a cellphone add-on that passively soaks up ambient T-rays and uses their energy to charge your phone.
Credit: José-Luis Olivares, MIT

Any device that sends out a Wi-Fi signal also emits terahertz waves —electromagnetic waves with a frequency somewhere between microwaves and infrared light. These high-frequency radiation waves, known as “T-rays,” are also produced by almost anything that registers a temperature, including our own bodies and the inanimate objects around us.

Terahertz waves are pervasive in our daily lives, and if harnessed, their concentrated power could potentially serve as an alternate energy source. Imagine, for instance, a cellphone add-on that passively soaks up ambient T-rays and uses their energy to charge your phone. However, to date, terahertz waves are wasted energy, as there has been no practical way to capture and convert them into any usable form.

Now physicists at MIT have come up with a blueprint for a device they believe would be able to convert ambient terahertz waves into a direct current, a form of electricity that powers many household electronics.

This schematic figure, from the researchers’ paper, shows a green square that represents graphene on top of a square of another material. The red lines represent terahertz waves. The blue triangles represent antenna that surround the square to capture the terahertz waves and focus the waves to the square.
This schematic figure, from the researchers’ paper, shows a green square that represents graphene on top of a square of another material. The red lines represent terahertz waves. The blue triangles represent antenna that surround the square to capture the terahertz waves and focus the waves to the square.
Credit: Courtesy of the researchers

Their design takes advantage of the quantum mechanical, or atomic behavior of the carbon material graphene. They found that by combining graphene with another material, in this case, boron nitride, the electrons in graphene should skew their motion toward a common direction. Any incoming terahertz waves should “shuttle” graphene’s electrons, like so many tiny air traffic controllers, to flow through the material in a single direction, as a direct current.

The researchers have published their results today in the journal Science Advances, and are working with experimentalists to turn their design into a physical device.

“We are surrounded by electromagnetic waves in the terahertz range,” says lead author Hiroki Isobe, a postdoc in MIT’s Materials Research Laboratory. “If we can convert that energy into an energy source we can use for daily life, that would help to address the energy challenges we are facing right now.”

Isobe’s co-authors are Liang Fu, the Lawrence C. and Sarah W. Biedenharn Career Development Associate Professor of Physics at MIT; and Su-yang Xu, a former MIT postdoc who is now an assistant professor chemistry at Harvard University.

Breaking graphene’s symmetry

Over the last decade, scientists have looked for ways to harvest and convert ambient energy into usable electrical energy. They have done so mainly through rectifiers, devices that are designed to convert electromagnetic waves from their oscillating (alternating) current to direct current.

Most rectifiers are designed to convert low-frequency waves such as radio waves, using an electrical circuit with diodes to generate an electric field that can steer radio waves through the device as a DC current. These rectifiers only work up to a certain frequency, and have not been able to accommodate the terahertz range.

A few experimental technologies that have been able to convert terahertz waves into DC current do so only at ultracold temperatures — setups that would be difficult to implement in practical applications.

Instead of turning electromagnetic waves into a DC current by applying an external electric field in a device, Isobe wondered whether, at a quantum mechanical level, a material’s own electrons could be induced to flow in one direction, in order to steer incoming terahertz waves into a DC current.

Such a material would have to be very clean, or free of impurities, in order for the electrons in the material to flow through without scattering off irregularities in the material. Graphene, he found, was the ideal starting material.

To direct graphene’s electrons to flow in one direction, he would have to break the material’s inherent symmetry, or what physicists call “inversion.” Normally, graphene’s electrons feel an equal force between them, meaning that any incoming energy would scatter the electrons in all directions, symmetrically. Isobe looked for ways to break graphene’s inversion and induce an asymmetric flow of electrons in response to incoming energy.

Looking through the literature, he found that others had experimented with graphene by placing it atop a layer of boron nitride, a similar honeycomb lattice made of two types of atoms — boron and nitrogen. They found that in this arrangement, the forces between graphene’s electrons were knocked out of balance: Electrons closer to boron felt a certain force while electrons closer to nitrogen experienced a different pull. The overall effect was what physicists call “skew scattering,” in which clouds of electrons skew their motion in one direction.

Isobe developed a systematic theoretical study of all the ways electrons in graphene might scatter in combination with an underlying substrate such as boron nitride, and how this electron scattering would affect any incoming electromagnetic waves, particularly in the terahertz frequency range.

He found that electrons were driven by incoming terahertz waves to skew in one direction, and this skew motion generates a DC current, if graphene were relatively pure. If too many impurities did exist in graphene, they would act as obstacles in the path of electron clouds, causing these clouds to scatter in all directions, rather than moving as one.

“With many impurities, this skewed motion just ends up oscillating, and any incoming terahertz energy is lost through this oscillation,” Isobe explains. “So we want a clean sample to effectively get a skewed motion.”

One direction

They also found that the stronger the incoming terahertz energy, the more of that energy a device can convert to DC current. This means that any device that converts T-rays should also include a way to concentrate those waves before they enter the device.

With all this in mind, the researchers drew up a blueprint for a terahertz rectifier that consists of a small square of graphene that sits atop a layer of boron nitride and is sandwiched within an antenna that would collect and concentrate ambient terahertz radiation, boosting its signal enough to convert it into a DC current.

“This would work very much like a solar cell, except for a different frequency range, to passively collect and convert ambient energy,” Fu says.

The team has filed a patent for the new “high-frequency rectification” design, and the researchers are working with experimental physicists at MIT to develop a physical device based on their design, which should be able to work at room temperature, versus the ultracold temperatures required for previous terahertz rectifiers and detectors.

“If a device works at room temperature, we can use it for many portable applications,” Isobe says.

He envisions that, in the near future, terahertz rectifiers may be used, for instance, to wirelessly power implants in a patient’s body, without requiring surgery to change an implant’s batteries. Such devices could also convert ambient Wi-Fi signals to charge up personal electronics such as laptops and cellphones.

“We are taking a quantum material with some asymmetry at the atomic scale, that can now be utilized, which opens up a lot of possibilities,” Fu says.

This research was funded in part by the U.S. Army Research Laboratory and the U.S. Army Research Office through the Institute for Soldier Nanotechnologies (ISN).



Contacts and sources:
Jennifer Chu
MIT - Massachusetts Institute of Technology







MIT: An Experimental Peptide Could Block Covid-19 from Entering Human Cells

In hopes of developing a treatment for Covid-19), a team of chemists(opens in new window) has designed a drug candidate that may block coronaviruses’ ability to enter human cells. It binds to the protein that the viruses use to enter cells, potentially disarming it.
the covid-19 virus with blue peptides wrapped around the virus's spikes
Photo collage: Christine Daniloff, MIT

The research described in this article has been published on a preprint server but has not yet been peer-reviewed by scientific or medical experts.

In hopes of developing a possible treatment for Covid-19, a team of MIT chemists has designed a drug candidate that they believe may block coronaviruses’ ability to enter human cells. The potential drug is a short protein fragment, or peptide, that mimics a protein found on the surface of human cells.

The researchers have shown that their new peptide can bind to the viral protein that coronaviruses use to enter human cells, potentially disarming it.

“We have a lead compound that we really want to explore, because it does, in fact, interact with a viral protein in the way that we predicted it to interact, so it has a chance of inhibiting viral entry into a host cell,” says Brad Pentelute, an MIT associate professor of chemistry, who is leading the research team.

The MIT team reported its initial findings in a preprint posted on bioRxiv, an online preprint server, on March 20. They have sent samples of the peptide to collaborators who plan to carry out tests in human cells.

Molecular targeting

Pentelute’s lab began working on this project in early March, after the Cryo-EM structure of the coronavirus spike protein, along with the human cell receptor that it binds to, was published by a research group in China. Coronaviruses, including SARS-CoV-2, which is causing the current Covid-19 outbreak, have many protein spikes protruding from their viral envelope.

Studies of SARS-CoV-2 have also shown that a specific region of the spike protein, known as the receptor binding domain, binds to a receptor called angiotensin-converting enzyme 2 (ACE2). This receptor is found on the surface of many human cells, including those in the lungs. The ACE2 receptor is also the entry point used by the coronavirus that caused the 2002-03 SARS outbreak.

In hopes of developing drugs that could block viral entry, Genwei Zhang, a postdoc in Pentelute’s lab, performed computational simulations of the interactions between the ACE2 receptor and the receptor binding domain of the coronavirus spike protein. These simulations revealed the location where the receptor binding domain attaches to the ACE2 receptor — a stretch of the ACE2 protein that forms a structure called an alpha helix.

“This kind of simulation can give us views of how atoms and biomolecules interact with each other, and which parts are essential for this interaction,” Zhang says. “Molecular dynamics helps us narrow down particular regions that we want to focus on to develop therapeutics.”

The MIT team then used peptide synthesis technology that Pentelute’s lab has previously developed, to rapidly generate a 23-amino acid peptide with the same sequence as the alpha helix of the ACE2 receptor. Their benchtop flow-based peptide synthesis machine can form linkages between amino acids, the buildings blocks of proteins, in about 37 seconds, and it takes less than an hour to generate complete peptide molecules containing up to 50 amino acids.

“We’ve built these platforms for really rapid turnaround, so I think that’s why we’re at this point right now,” Pentelute says. “It’s because we have these tools we’ve built up at MIT over the years.”

They also synthesized a shorter sequence of only 12 amino acids found in the alpha helix, and then tested both of the peptides using equipment at MIT’s Biophysical Instrumentation Facility that can measure how strongly two molecules bind together. They found that the longer peptide showed strong binding to the receptor binding domain of the Covid-19 spike protein, while the shorter one showed negligible binding.

Many variants

Although MIT has been scaling back on-campus research since mid-March, Pentelute’s lab was granted special permission allowing a small group of researchers to continue to work on this project. They are now developing about 100 different variants of the peptide in hopes of increasing its binding strength and making it more stable in the body.

“We have confidence that we know exactly where this molecule is interacting, and we can use that information to further guide refinement, so that we can hopefully get a higher affinity and more potency to block viral entry in cells,” Pentelute says.

In the meantime, the researchers have already sent their original 23-amino acid peptide to a research lab at the Icahn School of Medicine at Mount Sinai for testing in human cells and potentially in animal models of Covid-19 infection.

While dozens of research groups around the world are using a variety of approaches to seek new treatments for Covid-19, Pentelute believes his lab is one of a few currently working on peptide drugs for this purpose. One advantage of such drugs is that they are relatively easy to manufacture in large quantities. They also have a larger surface area than small-molecule drugs.

“Peptides are larger molecules, so they can really grip onto the coronavirus and inhibit entry into cells, whereas if you used a small molecule, it’s difficult to block that entire area that the virus is using,” Pentelute says. “Antibodies also have a large surface area, so those might also prove useful. Those just take longer to manufacture and discover.”

One drawback of peptide drugs is that they typically can’t be taken orally, so they would have to be either administered intravenously or injected under the skin. They would also need to be modified so that they can stay in the bloodstream long enough to be effective, which Pentelute’s lab is also working on.

“It’s hard to project how long it will take to have something we can test in patients, but my aim is to have something within a matter of weeks. If it turns out to be more challenging, it may take months,” he says.

In addition to Pentelute and Zhang, other researchers listed as authors on the preprint are postdoc Sebastian Pomplun, grad student Alexander Loftis, and research scientist Andrei Loas.


Contacts and sources:
Anne Trafton
MIT - Massachusetts Institute of Technology


Publication:  The first-in-class peptide binder to the SARS-CoV-2 spike protein
G. Zhang,  S. Pomplun,  A. R. Loftis,  A. Loas,  B. L. Pentelute 
doi: https://doi.org/10.1101/2020.03.19.999318 https://www.biorxiv.org/content/10.1101/2020.03.19.999318v1





Monday, March 30, 2020

A Martian Mash Up: Meteorites Tell Story of Mars' Water History


University of Arizona researchers probed Martian meteorites to reconstruct Mars’ chaotic history. Their findings suggest that Mars might not have had a global magma ocean.


Credit: NASA

In Jessica Barnes' palm is an ancient, coin-sized mosaic of glass, minerals and rocks as thick as a strand of wool fiber. It is a slice of Martian meteorite, known as Northwest Africa 7034 or Black Beauty, that was formed when a huge impact cemented together various pieces of the Martian crust.

Barnes is an assistant professor of planetary sciences in the University of Arizona Lunar and Planetary Laboratory. She and her team chemically analyzed the Black Beauty meteorite and the infamous Allan Hills 84001 meteorite – controversial in the 1990s for allegedly containing Martian microbes – to reconstruct Mars' water history and planetary origins.

Their analysis, published today in Nature Geoscience, showed that Mars likely received water from at least two vastly different sources early in its history. The variability the researchers found implies that Mars, unlike Earth and the moon, never had an ocean of magma completely encompassing the planet.

"These two different sources of water in Mars' interior might be telling us something about the kinds of objects that were available to coalesce into the inner, rocky planets," Barnes said.

Two distinct planetary precursors with vastly different water contents could have collided and never fully mixed, she said. "This context is also important for understanding the past habitability and astrobiology of Mars."

Reading the Water

"A lot of people have been trying to figure out Mars' water history," Barnes said. "Like, where did water come from? How long was it in the crust (surface) of Mars? Where did Mars' interior water come from? What can water tell us about how Mars formed and evolved?"

Barnes and her team were able to piece together Mars' water history by looking for clues in two types, or isotopes, of hydrogen. One hydrogen isotope contains one proton in its nucleus; this is sometimes called "light hydrogen." The other isotope is called deuterium, which contains a proton and a neutron in the nucleus; this is sometimes referred to as "heavy hydrogen." The ratio of these two hydrogen isotopes signals to a planetary scientist the processes and possible origins of water in the rocks, minerals and glasses in which they're found.

Meteorite Mystery

For about 20 years, researchers have been recording the isotopic ratios from Martian meteorites, and their data were all over the place. There seemed to be little trend, Barnes said.

The Northwest Africa 7034 meteorite. 
Photo: Institute of Meteoritics UNM

Water locked in Earth rocks is what's called unfractionated, meaning it doesn't deviate much from the standard reference value of ocean water – a 1:6,420 ratio of heavy to light hydrogen. Mars' atmosphere, on the other hand, is heavily fractionated – it is mostly populated by deuterium, or heavy hydrogen, likely because the solar wind stripped away the light hydrogen. Measurements from Martian meteorites – many of which were excavated from deep within Mars by impact events – ran the gamut between Earth and Mars' atmosphere measurements.

Barnes' team set out to investigate the hydrogen isotope composition of the Martian crust specifically by studying samples they knew originated from the crust: the Black Beauty and Allan Hills meteorites. Black Beauty was especially helpful because it's a mashup of surface material from many different points in Mars' history.

"This allowed us to form an idea of what Mars' crust looked like over several billions of years," Barnes said.

The isotopic ratios of the meteorite samples fell about midway between the value for Earth rocks and Mars' atmosphere. When the researchers' findings were compared with previous studies, including results from the Curiosity Rover, it seems that this was the case for most of Mars 4 billion-plus-year history.

"We thought, OK, this is interesting, but also kind of weird," Barnes said. "How do we explain this dichotomy where the Martian atmosphere is being fractionated, but the crust is basically staying the same over geological time?"

Jessica Barnes
Credit: UA

Barnes and her colleagues also grappled with trying to explain why the crust seemed so different from the Martian mantle – the rock layer that lies below.

"If you try and explain this fairly constant isotopic ratio of Mars' crust, you really can't use the atmosphere to do that," Barnes said. "But we know how crusts are formed. They're formed from molten material from the interior that solidifies on the surface."

"The prevailing hypothesis before we started this work was that the interior of Mars was more Earthlike and unfractionated, and so the variability in hydrogen isotope ratios within Martian samples was due to either terrestrial contamination or atmospheric implantation as it made its way off Mars," Barnes said.

The idea that Mars' interior was Earth-like in composition came from one study of a Martian meteorite thought to have originated from the mantle – the interior between the planet's core and its surface crust.

However, Barnes said, "Martian meteorites basically plot all over the place, and so trying to figure out what these samples are actually telling us about water in the mantle of Mars has historically been a challenge. The fact that our data for the crust was so different prompted us to go back through the scientific literature and scrutinize the data."

The researchers found that two geochemically different types of Martian volcanic rocks – enriched shergottites and depleted shergottites – contain water with different hydrogen isotope ratios. Enriched shergottites contain more deuterium than the depleted shergottites, which are more Earth-like, they found.

"It turns out that if you mix different proportions of hydrogen from these two kinds of shergottites, you can get the crustal value," Barnes said.

She and her colleagues think that the shergottites are recording the signatures of two different hydrogen – and by extension, water – reservoirs within Mars. The stark difference hints to them that more than one source might have contributed water to Mars and that Mars did not have a global magma ocean.




Contacts and sources:
Mikayla Mace
University of Arizona


Publication: Multiple early-formed water reservoirs in the interior of Mars.
Jessica J. Barnes, Francis M. McCubbin, Alison R. Santos, James M. D. Day, Jeremy W. Boyce, Susanne P. Schwenzer, Ulrich Ott, Ian A. Franchi, Scott Messenger, Mahesh Anand, Carl B. Agee. Nature Geoscience, 2020; DOI: 10.1038/s41561-020-0552-y




Experimental AI Tool Predicts Which Patients with Pandemic Virus Will Develop Serious Respiratory Disease



An artificial intelligence tool accurately predicted which patients newly infected with the COVID-19 virus would go on to develop severe respiratory disease.



Photo credit: metamorworks/Getty Images


An artificial intelligence tool accurately predicted which patients newly infected with the COVID-19 virus would go on to develop severe respiratory disease, a new study has found.

The work was led by NYU Grossman School of Medicine and NYU’s Courant Institute of Mathematical Sciences, in partnership with Wenzhou Central Hospital and Cangnan People's Hospital, both in Wenzhou, China.

Named “SARS-CoV-2,” the new virus causes the disease called “coronavirus disease 2019” or “COVID-19.” As of March 30, the virus had infected 735,560 patients worldwide. According to the World Health Organization, the illness has caused more than 34,800 deaths to date, more often among older patients with underlying health conditions. The New York State Department of Health has reported more than 33,700 cases to date in New York City.

Published online March 30 in the journal Computers, Materials & Continua, the study also revealed the best indicators of future severity and found that they were not as expected.

“While work remains to further validate our model, it holds promise as another tool to predict the patients most vulnerable to the virus, but only in support of physicians’ hard-won clinical experience in treating viral infections,” says corresponding study author Megan Coffee, MD, PhD, clinical assistant professor in the Division of Infectious Disease & Immunology within the Department of Medicine at NYU Grossman School of Medicine.

“Our goal was to design and deploy a decision-support tool using AI capabilities—mostly predictive analytics—to flag future clinical coronavirus severity,” adds co-author Anasse Bari, a clinical assistant professor in computer science at the Courant institute. “We hope that the tool, when fully developed, will be useful to physicians as they assess which moderately ill patients really need beds and who can safely go home, with hospital resources stretched thin.”

Surprise Predictors
For the study, demographic, laboratory, and radiological findings were collected from 53 patients as each tested positive in January 2020 for the SARS-CoV2 virus at the two Chinese hospitals. Symptoms were typically mild to begin with, including cough, fever, and stomach upset. In a minority of patients, however, severe symptoms developed with a week, including pneumonia.

The goal of the new study was to determine whether AI techniques could help to accurately predict which patients with the virus would go on to develop Acute Respiratory Distress Syndrome or ARDS, the fluid build-up in the lungs that can be fatal in the elderly.

For the new study, the researchers designed computer models that make decisions based on the data fed into them, with programs getting “smarter” the more data they consider. Specifically, the current study used decision trees that track series of decisions between options and that model the potential consequences of choices at each step in a pathway.

The researchers were surprised to find that characteristics considered to be hallmarks of COVID-19, like certain patterns seen in lung images (e.g. ground glass opacities), fever, and strong immune responses, were not useful in predicting which of the many patients with initial, mild symptoms would go to develop severe lung disease. Neither age nor gender were helpful in predicting serious disease, although past studies had found men over 60 to be at higher risk.

Instead, the new AI tool found that changes in three features—levels of the liver enzyme alanine aminotransferase (ALT), reported myalgia, and hemoglobin levels—were most accurately predictive of subsequent, severe disease. Together with other factors, the team reported being able to predict risk of ARDS with up to 80 percent accuracy.

ALT levels—which rise dramatically as diseases like hepatitis damage the liver—were only a bit higher in patients with COVID-19, researchers say, but still featured prominently in prediction of severity. In addition, deep muscle aches (myalgia) were also more commonplace and have been linked by past research to higher general inflammation in the body.

Lastly, higher levels of hemoglobin, the iron-containing protein that enables blood cells to carry oxygen to bodily tissues, were also linked to later respiratory distress. Could this explained by other factors, like unreported smoking of tobacco, which has long been linked to increased hemoglobin levels. Of the 33 patients at Wenzhou Central Hospital interviewed on smoking status, the two who reported having smoked, also reported that they had quit.

Limitations of the study, say the authors, included the relatively small data set and the limited clinical severity of disease in the population studied. The latter may be due in part to an as yet unexplained dearth of elderly patients admitted into the hospitals during the study period. The average patient age was 43.

“I will be paying more attention in my clinical practice to our data points, watching patients closer if they, for instance, complain of severe myalgia,” adds Coffee. “It’s exciting to be able to share data with the field in real time when it can be useful. In all past epidemics, journal papers only published well after the infections had waned.”

Along with Coffee and Bari, authors of the study included first author Xiangao Jiang, along with Jianping Huang, Jichan Shi, Jianyi Dai, Jing Cai, Zhengxing Wu, and Guiqing He, in the Department of Infectious Diseases at Wenzhou Central Hospital. Also from Wenzhou Central Hospital was author Yitong Huang of Department of Gynaecology.

Also study authors were Junzhang Wang of NYU’s Courant Institute of Mathematical Sciences, Xinyue Jiang of Columbia University, and Tianxiao Zhang in Department of Infectious Diseases at Cangnan People's Hospital. Coffee is also adjunct faculty in the Department of Population and Family Health at the Mailman School of Public Health at Columbia.




Contacts and sources:
NYU Langone Health / NYU School of Medicine


Publication: Towards an Artificial Intelligence Framework for Data-Driven Prediction of Coronavirus Clinical Severity. Xiangao Jiang, Megan Coffee, Anasse Bari, Junzhang Wang, Xinyue Jiang, Jianping Huang, Jichan Shi, Jianyi Dai, Jing Cai, Tianxiao Zhang, Zhengxing Wu, Guiqing He, Yitong Huang. CMC-Computers, Materials & Continua, 2020 DOI: 10.32604/cmc.2020.010691




Sunday, March 29, 2020

Close the Lid Before Flushing: COVID-19 Lives on in Stool after It Clears the Lungs



The Faculty of Medicine at The Chinese University of Hong Kong (CU Medicine) analysed more than 300 specimens (including sputum, nasopharyngeal swabs, deep throat saliva, blood, urine and stool) from 14 Hong Kong patients confirmed with COVID-19 and discovered that the virus was detectable in the fecal samples of all patients, regardless of the degree of illness. 

Three out of 14 patients still had viruses in their stool samples even though the virus was no longer found in sputum, nasopharyngeal and deep throat saliva samples. This finding suggests that virus shedding in stool is common and can be an alternative screening tool. Importantly, we should not overlook the potential risk of environmental contamination by virus shedding in stool.

 CU Medicine analysed more than 300 specimens from 14 Hong Kong patients confirmed with COVID-19, and found all patients have their stool test positive of the coronavirus. (From left) Prof. Paul CHAN, Chairman of the Department of Microbiology; Prof. Francis CHAN, Dean of the Faculty of Medicine and Director of the Centre for Gut Microbiota Research; and Prof. David HUI, Chairman of the Department of Medicine and Therapeutics, at CU Medicine.

Credit: CUHK

In view of the finding, CU Medicine will in the first stage screen stool and saliva for 100 asymptomatic close contacts admitted to the quarantine centers. This will help determine whether stool test can effectively detect COVID-19 in asymptomatic persons.

All Studied Patients Have COVID-19 Virus Detected in their Fecal Samples

The research team collected and analysed more than 300 specimens from 14 confirmed cases, including respiratory, blood, urine and stool samples, to understand the virus distribution in human body. Below are the main findings:
  • Sputum has the highest amount of coronavirus, more than 300 times as found in deep throat saliva.
  • All patients had their stool tested positive during their course of illness, regardless of the degree of illness.
  • The virus load in stool is comparable to deep throat saliva.
  • 3 out of 14 patients still had virus in their stool samples for 1-2 days even though the virus was no longer found in respiratory samples.
  • Blood positive rate was low.
  • All urine samples were negative.

Professor Paul Kay Sheung CHAN, Chairman of the Department of Microbiology, CU Medicine, remarked, “Risk of transmission is the highest from respiratory tract. Gastrointestinal tract is also an important route not to be ignored. For persons with productive cough, sputum is the best choice of self-collect specimen. For persons who cannot produce sputum, in addition to deep throat saliva, stool could be an alternative tool that enables early case identification in the community.”

Professor Francis KL CHAN, Dean of the Faculty of Medicine and Director of the Centre for Gut Microbiota Research at CUHK remarked, “Our study suggests that virus shedding in stool may have public health implications. First, it may serve as an alternative screening tool in people without respiratory symptoms. Second, virus shedding in stool may impose health hazard to others. Caretakers and food handlers should be particularly vigilant about their hand hygiene.”

Professor David Shu Cheong HUI, Chairman of the Department of Medicine and Therapeutics and Stanley Ho Professor of Respiratory Medicine at CU Medicine, explained that virus shedding in stool could contaminate the environment and the virus could be transmitted through mucosal surfaces of eyes, nose and mouth after people touch the contaminated surface. He reminded the public to stay alert on hand hygiene. He remarked, “The public are reminded of filling enough water into U-shaped water traps connected to bathroom floor drains and to close the toilet lid when they flush. All these measures help reduce the risk of infection.”


Prof. Francis CHAN reminds the public that virus shedding in stool may impose health hazard to others. Caretakers and food handlers should be particularly vigilant about their hand hygiene.

Credit: CUHK

Prof. Paul CHAN states that 3 patients still had coronavirus in their stool samples even though the virus was no longer found in respiratory samples. This finding should not be ignored.

Credit: CUHK

 Prof. David HUI explains that coronavirus shedding in stool can contaminate the environment and the virus can be transmitted through mucosal surfaces of eyes, nose and mouth after people touch the contaminated surface.

Credit: CUHK



Contacts and sources:
The Chinese University of Hong Kong (CUHK)








Coronavirus Pandemic Could Have Caused 40 Million Deaths If Left Unchecked



The outbreak of COVID-19 would likely have caused 40 million deaths this year in the absence of any preventative measures.

This is one of the findings of a new analysis by researchers at Imperial College London, which estimated the potential scale of the coronavirus pandemic across the globe, highlighting that failure to mitigate the impact could lead to huge loss of life.
Concept of the planet surrounded by viruses
Credit:

The report is the twelfth to be released by The WHO Collaborating Centre for Infectious Disease Modelling within the MRC Centre for Global Infectious Disease Analysis (GIDA), Abdul Latif Jameel Institute for Disease and Emergency Analytics (J-IDEA).

Researchers included a number of scenarios, such as what would have happened if the world had not reacted to COVID-19 (the “unmitigated scenario”). They also included two scenarios incorporating social distancing, which result in a single-peaked epidemic (“mitigated scenarios”), and several scenarios for suppressing the spread of the disease that can have the largest overall impact in terms of reducing disease and deaths.

According to the unmitigated scenario, if left unchecked the virus could have infected 7 billion people and caused in the region of 40 million deaths this year. Social distancing to reduce the rate of social contacts by 40 per cent, coupled with a 60 per cent reduction in social contacts among the elderly population (at highest risk) could reduce this burden by around half. However, even at this level of reduction, health systems in all countries would be rapidly overwhelmed, the modelling revealed.

Dr Patrick Walker, an author of the report from Imperial, said: "We estimate that the world faces an unprecedented acute public health emergency in the coming weeks and months. Our findings suggest that all countries face a choice between intensive and costly measures to suppress transmission or risk health systems becoming rapidly overwhelmed. However, our results highlight that rapid, decisive and collective action now will save millions of lives in the next year"
Proven health measures

In the latest report, the team show that rapid adoption of proven public health measures – including testing and isolation of cases and wider social distancing to prevent onward transmission – are critical in curbing the impact of the pandemic.

The modelling showed that implementing measures early on can have a dramatic impact.

If all countries were to adopt this strategy at 0.2 deaths per 100,000 population per week, 95 per cent of the deaths could be averted, saving 38.7 million lives.

However, if this strategy is adopted later (1.6 deaths per 100,000 population per week), then this figure drops to 30.7 million.

“Rapid, decisive and collective action is required by all countries to limit the effect of this pandemic,” said Professor Azra Ghani, report author from MRC GIDA.

“Acting early has the potential to reduce mortality by as much as 95 per cent, saving 38.7 million lives. At the same time, consideration needs to be given to the broader impact of all measures that are put in place to ensure that those that are most vulnerable are protected from the wider health, social and economic impacts of such action.”

The results demonstrate the burden likely to be faced by low- and middle-income countries. For most scenarios, the COVID-19 pandemic is likely to overwhelm already over-stretched health systems in these settings and the wider social and economic costs of suppression will be high.

Professor Neil Ferguson, Director of MRC GIDA and J-IDEA at Imperial, said: “Our research adds to the growing evidence that the COVID-19 pandemic poses a grave global public health threat. Countries need to act collectively to rapidly respond to this fast-growing epidemic. Sharing both resources and best practice is critically important if the potentially catastrophic impacts of the pandemic are to be prevented at a global level.”

Report author Charlie Whittaker, a PhD student at Imperial, added: “This work highlights the need for swift and effective implementation of suppression measures if catastrophe is to be averted, but also that serious consideration needs to be given to these strategies - particularly in resource poor settings where the wider societal and economic impact of such intensive approaches might be higher.”

The researchers stress the models are not predictions of what will happen, but they illustrate the magnitude of the problem and the benefits of rapid, decisive and collective action.

The team is now sharing individual country outputs, making the data available to enable countries to use it to guide planning.

The full report ‘The Global Impact of COVID-19 and Strategies for Mitigation and Suppression’ is available on the MRC GIDA report website.


Contacts and sources:
Ryan O'Hare
Imperial College London







Gas Impacted by Young Jets from Supermassive Black Hole

Astronomers obtained the first resolved image of disturbed gaseous clouds in a galaxy 11 billion light-years away by using ALMA.

Reconstructed images of what MG J0414+0534 would look like if gravitational lensing effects were turned off. The emissions from dust and ionized gas around a quasar are shown in red. The emissions from carbon monoxide gas are shown in green, which have a bipolar structure along the jets.
Credit: ALMA (ESO/NAOJ/NRAO), K. T. Inoue et al.


Astronomers obtained the first resolved image of disturbed gaseous clouds in a galaxy 11 billion light-years away by using the Atacama Large Millimeter/submillimeter Array (ALMA). The team found that the disruption is caused by young powerful jets ejected from a supermassive black hole residing at the center of the host galaxy. This result will cast light on the mystery of the evolutionary process of galaxies in the early Universe.

It is commonly known that black holes exert strong gravitational attraction on surrounding matter. However, it is less well known that some black holes have fast-moving streams of ionized matter, called jets. In some nearby galaxies, evolved jets blow off galactic gaseous clouds, resulting in suppressed star formation. Therefore, to understand the evolution of galaxies, it is crucial to observe the interaction between black hole jets and gaseous clouds throughout cosmic history. However, it had been difficult to obtain clear evidence of such interaction, especially in the early Universe.

In order to obtain such clear evidence, the team used ALMA to observe an interesting object known as MG J0414+0534. A distinctive feature of MG J0414+0534 is that the paths of light traveling from it to Earth are significantly distorted by the gravity of another ‘lensing’ galaxy between MG J0414+0534 and us, causing significant magnification.

“This distortion works as a ‘natural telescope’ to enable a detailed view of distant objects,” says Takeo Minezaki, an associate professor at the University of Tokyo.

Another feature is that MG J0414+0534 has a supermassive black hole with bipolar jets at the center of the host galaxy. The team was able to reconstruct the ‘true’ image of gaseous clouds as well as the jets in MG J0414+0534 by carefully accounting for the gravitational effects exerted by the intervening lensing galaxy.

“Combining this cosmic telescope and ALMA’s high-resolution observations, we obtained exceptionally sharp vision, that is 9,000 times better than human eyesight,” adds Kouichiro Nakanishi, a project associate professor at the National Astronomical Observatory of Japan/SOKENDAI. “With this extremely high resolution, we were able to obtain the distribution and motion of gaseous clouds around jets ejected from a supermassive black hole.”

Thanks to such a superior resolution, the team found that gaseous clouds along the jets have violent motion with speeds as high as 600 km/s, showing clear evidence of impacted gas. Moreover, it turned out that the size of the impacted gaseous clouds and the jets are much smaller than the typical size of a galaxy at this age.

“We are perhaps witnessing the very early phase of jet evolution in the galaxy,” says Satoki Matsushita, a research fellow at Academia Sinica Institute of Astronomy and Astrophysics. “It could be as early as several tens of thousands of years after the launch of the jets.”

“MG J0414+0534 is an excellent example because of the youth of the jets,” summarizes Kaiki Inoue, a professor at Kindai University, Japan, and the lead author of the research paper which appeared in the Astrophysical Journal Letters. “We found telltale evidence of significant interaction between jets and gaseous clouds even in the very early evolutionary phase of jets. I think that our discovery will pave the way for a better understanding of the evolutionary process of galaxies in the early Universe.”

These observation results are presented in K. T. Inoue et al. “ALMA 50-parsec resolution imaging of jet-ISM interaction in the lensed quasar MG J0414+0534” appeared in the Astrophysical Journal Letters on March 27, 2020.


Contacts and sources:
Hitoshi Yamaoka
National Astronomical Observatory of Japan (NAOJ)
Publication:





Artificial Intelligence Identifies Optimal Material Formula



One algorithm replaces countless time-consuming experiments.


Nanostructured layers boast countless potential properties – but how can the most suitable one be identified without any long-term experiments? A team from the Materials Discovery Department at Ruhr-Universität Bochum (RUB) has ventured a shortcut: using a machine learning algorithm, the researchers were able to reliably predict the properties of such a layer. Their report was published in the new journal “Communications Materials” from 26 March 2020.

Porous or dense, columns or fibres

During the manufacture of thin films, numerous control variables determine the condition of the surface and, consequently, its properties. Relevant factors include the composition of the layer as well as process conditions during its formation, such as temperature. All these elements put together result in the creation of either a porous or a dense layer during the coating process, with atoms combining to form columns or fibres.

A look into the sputtering system where nanostructured layers are generated. 
Blick in die Anlage
Credit: © Lars Banko

 “In order to find the optimal parameters for an application, it used to be necessary to conduct countless experiments under different conditions and with different compositions; this is an incredibly complex process,“ explains Professor Alfred Ludwig, Head of the Materials Discovery and Interfaces Team.

Findings yielded by such experiments are so-called structure zone diagrams, from which the surface of a certain composition resulting from certain process parameters can be read. “Experienced researchers can subsequently use such a diagram to identify the most suitable location for an application and derive the parameters necessary for producing the suitable layer,” points out Ludwig. “The entire process requires an enormous effort and is highly time consuming.”

Algorithm predicts surface

Striving to find a shortcut towards the optimal material, the team took advantage of artificial intelligence, more precisely machine learning. To this end, PhD researcher Lars Banko, together with colleagues from the Interdisciplinary Centre for Advanced Materials Simulation at RUB, Icams for short, modified a so-called generative model. He then trained this algorithm to generate images of the surface of a thoroughly researched model layer of aluminium, chromium and nitrogen using specific process parameters, in order to predict what the layer would look like under the respective conditions.

“We fed the algorithm with a sufficient amount of experimental data in order to train it, but not with all known data,” stresses Lars Banko. Thus, the researchers were able to compare the results of the calculations with those of the experiments and analyse how reliable its prediction was. The results were conclusive: “We combined five parameters and were able to look in five directions simultaneously using the algorithm – without having to conduct any experiments at all,” outlines Alfred Ludwig. “We have thus shown that machine learning methods can be transferred to materials research and can help to develop new materials for specific purposes.”



Contacts and sources:
Prof. Dr. Alfred Ludwig
Materials Discovery and Interfaces
Institute for Materials
Department of Mechanical Engineering

Ruhr-Universitaet-Bochum




Publication: Lars Banko, Yury Lysogorskiy, Dario Grochla, Dennis Naujoks, Ralf Drautz, Alfred Ludwig: Predicting structure zone diagrams for thin film synthesis by generative machine learning, in: Communications Materials, 2020, DOI: 10.1038/s43246-020-0017-2





Researchers Find Key To Keep Working Memory Working



Working memory, the ability to hold a thought in mind even through distraction, is the foundation of abstract reasoning and a defining characteristic of the human brain. It is also impaired in disorders such as schizophrenia and Alzheimer’s disease.

Now Yale researchers have found a key molecule that helps neurons maintain information in working memory, which could lead to potential treatments for neurocognitive disorders, they report March 19 in the journal Neuron.

“Working memory arises from neuronal circuits in the prefrontal cortex,” said senior author Min Wang, senior research scientist in neuroscience. “We have been learning that these circuits have special molecular maintenance requirements.”

Areas of the brain involved in memory formation
File:Brain regions involved in memory formation.jpg
Credit: US Government / Wikimedia Commons

Neurons in the prefrontal cortex excite each other to keep information “in mind.” These circuits act as a sort of mental sketch pad, allowing us to remember that caramelized onions are cooking in the frying pan while we search the next room for a pair of scissors.

The new study shows that these prefrontal cortical circuits depend upon the neurotransmitter acetylcholine stimulating muscarinic M1 receptors aligned on the surface of neurons of the prefrontal cortex. Blocking muscarinic M1 receptors reduced the firing of neurons involved in working memory, while activating the M1 receptors helped restore neuronal firing. Because acetylcholine actions at M1 receptors are reduced in schizophrenia and Alzheimer’s disease, the M1 receptor may serve as a potential therapeutic target, the authors suggest.

Wang notes that a drug currently under development for the treatment of schizophrenia stimulates this M1 receptor and has shown promise in early clinical trials.

Yale’s Veronica Galvin is first author of the paper, which was primarily funded by the National Institutes of Health.
Contacts and sources:
Bill Hathaway
Yale University






Regular Tub Bathing Linked To Lower Risk Of Death From Cardiovascular Disease


Daily hot bath seems to be more effective than once to twice weekly or none at all.

Regular tub bathing is linked to a lower risk of death from heart disease and stroke, indicates a long term study, published online in the journal Heart.

And the higher the ‘dose,’ the better it seems to be for cardiovascular health, with a daily hot bath seemingly more protective than a once or twice weekly one, the findings indicate.

Honoré Daumier - The Bathers, plate 12-The Hot Bath - 1925.1014 - Cleveland Museum of Art
Credit: Dudley P. Allen Fund / Source/Photographer https://clevelandart.org/art/1925.1014
Wikimedia Commons 
\
A linked editorial sounds a note of caution, however, because sudden death associated with hot baths is relatively common in Japan, where the study was conducted.

Having a bath is associated with good sleep quality and better self-rated health, but it’s not clear what its long term impact might be on cardiovascular disease risk, including heart attack, sudden cardiac death, and stroke.

To explore this further, the researchers drew on participants in The Japan Public Health Center based Study Cohort 1, a population based tracking study of more than 61,000 middle aged adults (45 to 59 years).

At the start of the study in 1990, some 43,000 participants completed a detailed questionnaire on their bathing habits and potentially influential factors: lifestyle, to include exercise, diet, alcohol intake, weight (BMI); average sleep duration; and medical history and current medicines use.

Each participant was monitored until death or completion of the study at the end of December 2009, whichever came first, with the final analysis based on 30,076 people.

During the monitoring period, 2097 cases of cardiovascular disease occurred: 275 heart attacks; 53 sudden cardiac deaths; and 1769 strokes.

After taking account of potentially influential factors, analysis of the data showed that compared with a once or twice weekly bath or no bath at all, a daily hot bath was associated with a 28% lower overall risk of cardiovascular disease, and a 26% lower overall risk of stroke.

The frequency of tub bathing wasn’t associated with a heightened risk of sudden cardiac death, or with a particular type of stroke, called subarachnoid haemorrhage (bleed into the space surrounding the brain).

Further analysis of preferred water temperature indicated 26% lower and 35% lower risks of overall cardiovascular disease for warm and hot water, respectively. But no significant associations emerged for overall stroke risk and water temperature.

After excluding those participants who developed cardiovascular disease within 5 or 10 years of the start of the study, the associations found weren’t quite as strong, but nevertheless still remained statistically significant.

This is an observational study, and as such, can’t establish cause, added to which changes in bathing frequency weren’t tracked during the monitoring period. The typical style of Japanese bathing also includes immersion to shoulder height, and this may be a critical factor.

But, say the researchers, previously published research has pointed to a link between heat exposure and cardiovascular disease prevention: this is because the effects of heat on the body are not dissimilar to those of exercise.

“We found that frequent tub bathing was significantly associated with a lower risk of hypertension, suggesting that a beneficial effect of tub bathing on risk of [cardiovascular disease] may in part be due to a reduced risk of developing hypertension,” write the researchers.

They acknowledge that taking a hot bath is not without its risk, particularly if the temperature is too high, a point that is taken up by Dr Andrew Felix Burden in a linked editorial.

“There can be no doubt about the potential dangers of bathing in hot water, and the occurrence of death from this increases with age, as well as with the temperature of the water,” he writes.

Although cardiovascular disease itself is unlikely to be the cause of these deaths, overheating, leading to confusion and drowning, most likely is, he suggests.

“Investigations into the potential cardiovascular benefit of heat-free immersion in warm to hot water are needed,” he says. “In the meanwhile, caution is needed because of the higher mortality associated with such bathing in an unselected population.”




Contacts and sources:
BMJ

Publication: Tub bathing and heart disease. Andrew Felix Burden. Heart, 2020; heartjnl-2019-316187 DOI: 10.1136/heartjnl-2019-316187




Chandra Data Tests "Theory of Everything"


Astronomers used Chandra to perform a test of string theory, a possible "theory of everything" that would tie all of known physics together.


The researchers were looking for a type of particle known as an "axion" and other similar particles.

Galaxy clusters with their strong magnetic fields and X-ray emission can be excellent places to search for evidence for axions.

The team looked at the Perseus galaxy cluster for over 5 days with Chandra, but did not find signals of any axion-like particles.

Image credit: NASA/CXC/Cambridge Univ./C.S. Reynolds

Astronomers using NASA's Chandra X-ray Observatory have made one of the first experimental tests of string theory, a set of models intended to tie together all known forces, particles, and interactions. As described in our latest press release, researchers used Chandra to look for signs of an as-yet undetected particle predicted by string theory. The lack of a detection in these Chandra observations helps rule out some versions of string theory.

The team looked for extraordinarily low-mass "axion-like" particles in the Perseus galaxy cluster, shown in a Chandra image in the main panel of this graphic (red, green and blue colors are low, medium and high X-ray energies respectively). Galaxy clusters, the largest structures in the Universe held together by gravity, offer an excellent opportunity to search for these particles. In a galaxy cluster, X-ray photons from an embedded or a background source can travel through a large amount of hot gas permeated with magnetic field lines. 

Some of the X-ray photons may undergo conversion into axion-like particles, or the other way around, along this journey. A simplified illustration shows this process, with shorter wavelength X-ray photons (in blue) converting into axion-like particles (yellow) and back to photons, as they travel across magnetic field lines (grey) in the cluster. Longer wavelength X-ray photons (red) are converting into axion-like particles, but not back into photons. Such conversions would cause a distortion in the X-ray spectrum (the amount of X-rays at different energies) of a bright or embedded source of X-rays.


Illustration Credit: Amanda Smith/Institute of Astronomy/University of Cambridge

Astronomers obtained a long Chandra observation, lasting over five days, of the central supermassive black hole in the center of the Perseus galaxy cluster (shown in the inset.) The spectrum of the region around the black hole showed no distortions, allowing the team to rule out the presence of most types of axion-like particles in the relatively low mass range their search was sensitive to.

Here the Chandra spectrum (red) of Perseus' central black hole shows the intensity of X-rays as a function of X-ray energy, along with an example (black) of a model X-ray spectrum predicted if axion-like particles were actually being converted from and into photons. To highlight the distortions that could have been detected, the data divided by the example model are also shown.


Credit: NASA/CXC/Cambridge Univ./C.S. Reynolds

One possible interpretation of this work is that axion-like particles do not exist. Another possible interpretation is that the particles undergo conversion from and into photons less easily than some particle physicists have expected. They also could have higher masses than probed with the Chandra data.

Image credit: NASA/CXC/Cambridge Univ./C.S. Reynolds

There has been a surge of interest in studies of these particles in recent years for three reasons: First, despite a lot of work, there continues to be no detection of Weakly Interacting Massive Particles (WIMPs), either with gamma-ray observations, or earth-based experiments that could explain the nature of dark matter. These particles are predicted to interact with normal matter only via the weak force, and have been considered to be one of the strongest candidates for dark matter. Secondly, scientists have realized that axions and axion-like particles are predicted by string theory. Finally, there are a large number of experiments or observations that can be done to search for these particles.



A paper describing these results appeared in the February 10th, 2020 issue of The Astrophysical Journal and is available online. The authors are Christopher Reynolds (University of Cambridge, UK), David Marsh (Stockholm University, Sweden), Helen Russell (University of Nottingham, UK), Andrew C. Fabian (University of Cambridge), Robyn Smith (University of Maryland in College Park, Francesco Tombesi (University of Rome, Italy), and Sylvain Veilleux (University of Maryland).

NASA's Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center controls science and flight operations from Cambridge and Burlington, Massachusetts.











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Revisiting Decades-Old Voyager 2 Data, Scientists Find One More Secret



Eight and a half years into its grand tour of the solar system, NASA’s Voyager 2 spacecraft was ready for another encounter. It was Jan. 24, 1986, and soon it would meet the mysterious seventh planet, icy-cold Uranus.

Voyager 2 took this image as it approached the planet Uranus on Jan. 14, 1986. The planet’s hazy bluish color is due to the methane in its atmosphere, which absorbs red wavelengths of light.

Credits: NASA/JPL-Caltech

Over the next few hours, Voyager 2 flew within 50,600 miles (81,433 kilometers) of Uranus’ cloud tops, collecting data that revealed two new rings, 11 new moons and temperatures below minus 353 degrees Fahrenheit (minus 214 degrees Celsius). The dataset is still the only up-close measurements we have ever made of the planet.

Three decades later, scientists reinspecting that data found one more secret.

Unbeknownst to the entire space physics community, 34 years ago Voyager 2 flew through a plasmoid, a giant magnetic bubble that may have been whisking Uranus’s atmosphere out to space. The finding, reported in Geophysical Research Letters, raises new questions about the planet’s one-of-a-kind magnetic environment.

A wobbly magnetic oddball

Planetary atmospheres all over the solar system are leaking into space. Hydrogen springs from Venus to join the solar wind, the continuous stream of particles escaping the Sun. Jupiter and Saturn eject globs of their electrically-charged air. Even Earth’s atmosphere leaks. (Don’t worry, it will stick around for another billion years or so.)

The effects are tiny on human timescales, but given long enough, atmospheric escape can fundamentally alter a planet’s fate. For a case in point, look at Mars.

“Mars used to be a wet planet with a thick atmosphere,” said Gina DiBraccio, space physicist at NASA’s Goddard Space Flight Center and project scientist for the Mars Atmosphere and Volatile Evolution, or MAVEN mission. “It evolved over time” — 4 billion years of leakage to space — “to become the dry planet we see today.”

Atmospheric escape is driven by a planet’s magnetic field, which can both help and hinder the process. Scientists believe magnetic fields can protect a planet, fending off the atmosphere-stripping blasts of the solar wind. But they can also create opportunities for escape, like the giant globs cut loose from Saturn and Jupiter when magnetic field lines become tangled. Either way, to understand how atmospheres change, scientists pay close attention to magnetism.

That’s one more reason Uranus is such a mystery. Voyager 2’s 1986 flyby revealed just how magnetically weird the planet is.

“The structure, the way that it moves … ,” DiBraccio said, “Uranus is really on its own.”

Unlike any other planet in our solar system, Uranus spins almost perfectly on its side — like a pig on a spit roast — completing a barrel roll once every 17 hours. Its magnetic field axis points 60 degrees away from that spin axis, so as the planet spins, its magnetosphere — the space carved out by its magnetic field — wobbles like a poorly-thrown football. Scientists still don’t know how to model it.


Animated GIF showing Uranus’ magnetic field. The yellow arrow points to the Sun, the light blue arrow marks Uranus’ magnetic axis, and the dark blue arrow marks Uranus’ rotation axis.

Animation of magnetic field and rotation of Uranus
Credits: NASA/Scientific Visualization Studio/Tom Bridgman

This oddity drew DiBraccio and her coauthor Dan Gershman, a fellow Goddard space physicist, to the project. Both were part of a team working out plans for a new mission to the 'ice giants' Uranus and Neptune, and they were looking for mysteries to solve. Uranus’ strange magnetic field, last measured more than 30 years ago, seemed like a good place to start.

So they downloaded Voyager 2’s magnetometer readings, which monitored the strength and direction of the magnetic fields near Uranus as the spacecraft flew by. With no idea what they’d find, they zoomed in closer than previous studies, plotting a new datapoint every 1.92 seconds. Smooth lines gave way to jagged spikes and dips. And that’s when they saw it: a tiny zigzag with a big story.

“Do you think that could be … a plasmoid?” Gershman asked DiBraccio, catching sight of the squiggle.

Magnetometer data from Voyager 2’s 1986 flyby of Uranus. The red line shows the data averaged over 8-minute periods, a time cadence used by several previous Voyager 2 studies. In black, the same data is plotted at a higher time resolution of 1.92 seconds, revealing the zigzag signature of a plasmoid.


Credits: NASA/Dan Gershman

Little known at the time of Voyager 2’s flyby, plasmoids have since become recognized as an important way planets lose mass. These giant bubbles of plasma, or electrified gas, pinch off from the end of a planet’s magnetotail — the part of its magnetic field blown back by the Sun like a windsock. With enough time, escaping plasmoids can drain the ions from a planet’s atmosphere, fundamentally changing its composition. They had been observed at Earth and other planets, but no one had detected plasmoids at Uranus — yet.

DiBraccio ran the data through her processing pipeline and the results came back clean. “I think it definitely is,” she said.

The bubble escape

The plasmoid DiBraccio and Gershman found occupied a mere 60 seconds of Voyager 2’s 45-hour-long flight by Uranus. It appeared as a quick up-down blip in the magnetometer data. “But if you plotted it in 3D, it would look like a cylinder,” Gershman said.

Comparing their results to plasmoids observed at Jupiter, Saturn and Mercury, they estimated a cylindrical shape at least 127,000 miles (204,000 kilometers) long, and up to roughly 250,000 miles (400,000 kilometers) across. Like all planetary plasmoids, it was full of charged particles — mostly ionized hydrogen, the authors believe.​

Readings from inside the plasmoid — as Voyager 2 flew through it — hinted at its origins. Whereas some plasmoids have a twisted internal magnetic field, DiBraccio and Gershman observed smooth, closed magnetic loops. Such loop-like plasmoids are typically formed as a spinning planet flings bits of its atmosphere to space. “Centrifugal forces take over, and the plasmoid pinches off,” Gershman said. According to their estimates, plasmoids like that one could account for between 15 and 55% of atmospheric mass loss at Uranus, a greater proportion than either Jupiter or Saturn. It may well be the dominant way Uranus sheds its atmosphere to space.

How has plasmoid escape changed Uranus over time? With only one set of observations, it’s hard to say.

“Imagine if one spacecraft just flew through this room and tried to characterize the entire Earth,” DiBraccio said. “Obviously it’s not going to show you anything about what the Sahara or Antarctica is like.”

But the findings help focus new questions about the planet. The remaining mystery is part of the draw. “It’s why I love planetary science,” DiBraccio said. “You’re always going somewhere you don’t really know.”



Contacts and sources:
Miles Hatfield
NASA’s Goddard Space Flight Center,