Wednesday, February 19, 2020

EU proposes rules for artificial intelligence to limit risks

by Kelvin Chan

The European Union unveiled proposals Wednesday to regulate artificial intelligence that call for strict rules and safeguards on risky applications of the rapidly developing technology.

The report is part of the bloc's wider digital strategy aimed at maintaining its position as the global pacesetter on technological standards. Big tech companies seeking to tap Europe's vast and lucrative market, including those from the U.S. and China, would have to play by any new rules that come into force.

The EU's executive Commission said it wants to develop a "framework for trustworthy artificial intelligence." European Commission President Ursula von der Leyen had ordered her top deputies to come up with a coordinated European approach to artificial intelligence and data strategy 100 days after she took office in December.

"We will be particularly careful where essential human rights and interests are at stake," von der Leyen told reporters in Brussels. "Artificial intelligence must serve people, and therefore artificial intelligence must always comply with people's rights."

EU leaders, keen on establishing "technological sovereignty," also released a strategy to unlock data from the continent's businesses and the public sector so it can be harnessed for further innovation in artificial intelligence. Officials in Europe, which doesn't have any homegrown tech giants, hope to to catch up with the U.S. and China by using the bloc's vast and growing trove of industrial data for what they anticipate is a coming wave of digital transformation.

They also warned that even more regulation for foreign tech companies is in store with the upcoming "Digital Services Act," a sweeping overhaul of how the bloc treats digital companies, including potentially holding them liable for illegal content posted on their platforms. A steady stream of Silicon Valley tech bosses, including Facebook CEO Mark Zuckerberg, Google CEO Sundar Pichai and Microsoft President Brad Smith, have visited Brussels in recent weeks as part of apparent lobbying efforts.

"It is not us that need to adapt to today's platforms. It is the platforms that need to adapt to Europe," said Thierry Breton, commissioner for the internal market. "That is the message that we delivered to CEOs of these platforms when they come to see us."

If the tech companies aren't able to build systems "for our people, then we will regulate, and we are ready to do this in the Digital Services Act at the end of the year," he said.

The EU's report said clear rules are needed to address "high-risk AI systems," such as those in recruitment, healthcare, law enforcement or transport, which should be "transparent, traceable and guarantee human oversight." Other artificial intelligence systems could come with labels certifying that they are in line with EU standards.

Artificial intelligence uses computers to process large sets of data and make decisions without human input. It is used, for example, to trade stocks in financial markets, or, in some countries, to scan faces in crowds to find criminal suspects.

While it can be used to improve healthcare, make farming more efficient or combat climate change, it also brings risks. It can be unclear what data artificial intelligence systems work off. Facial recognition systems can be biased against certain social groups, for example. There are also concerns about privacy and the use of the technology for criminal purposes, the report said.

European Commission President Ursula von der Leyen speaks during a presentation on Europe's Digital Future at EU headquarters in Brussels, Wednesday, Feb. 19, 2020. A report on artificial intelligence released Wednesday is part of the bloc's wider digital strategy aimed at maintaining its position as the global pacesetter on technological standards. (AP Photo/Virginia Mayo)
Eeuropean Commission President Ursula von der Leyen, right, talks to Commissioner for Europe Fit for the Digital Age Margrethe Vestager during a weekly College of Commissioners meeting at the EU headquarters in Brussels, Wednesday, Feb. 19, 2020. During the meeting, the College will set out plans on the EU's strategy to deal with the challenges of the digital age and the use of artificial intelligence. (AP Photo/Francisco Seco)
Eeuropean Commission President Ursula von der Leyen, center, greets Commissioner for European Green Deal Frans Timmermans, right, next to Commissioner for Economy Paolo Gentiloni during a weekly College of Commissioners meeting at the EU headquarters in Brussels, Wednesday, Feb. 19, 2020. During the meeting, the College will set out plans on the EU's strategy to deal with the challenges of the digital age and the use of artificial intelligence. (AP Photo/Francisco Seco)
Eeuropean Commission President Ursula von der Leyen arrives for a weekly College of Commissioners meeting at the EU headquarters in Brussels, Wednesday, Feb. 19, 2020. During the meeting, the College will set out plans on the EU's strategy to deal with the challenges of the digital age and the use of artificial intelligence. (AP Photo/Francisco Seco)
European Commissioner for Europe fit for the Digital Age Margrethe Vestager speaks during a presentation on Europe's Digital Future at EU headquarters in Brussels, Wednesday, Feb. 19, 2020. A report on artificial intelligence released Wednesday is part of the bloc's wider digital strategy aimed at maintaining its position as the global pacesetter on technological standards. (AP Photo/Virginia Mayo)
European Commissioner for Europe fit for the Digital Age Margrethe Vestager speaks during a presentation on Europe's Digital Future at EU headquarters in Brussels, Wednesday, Feb. 19, 2020. A report on artificial intelligence released Wednesday is part of the bloc's wider digital strategy aimed at maintaining its position as the global pacesetter on technological standards. (AP Photo/Virginia Mayo)
European Commissioner for Internal Market Thierry Breton, right, and European Commissioner for Europe fit for the Digital Age Margrethe Vestager participate in a presentation of Europe's Digital Future at EU headquarters in Brussels, Wednesday, Feb. 19, 2020. A report on artificial intelligence released Wednesday is part of the bloc's wider digital strategy aimed at maintaining its position as the global pacesetter on technological standards. (AP Photo/Virginia Mayo)
European Commission President Ursula von der Leyen speaks during a presentation on Europe's Digital Future at EU headquarters in Brussels, Wednesday, Feb. 19, 2020. A report on artificial intelligence released Wednesday is part of the bloc's wider digital strategy aimed at maintaining its position as the global pacesetter on technological standards. (AP Photo/Virginia Mayo)
Eeuropean Commission President Ursula von der Leyen, right, talks to Commissioner for Europe Fit for the Digital Age Margrethe Vestager during a weekly College of Commissioners meeting at the EU headquarters in Brussels, Wednesday, Feb. 19, 2020. During the meeting, the College will set out plans on the EU's strategy to deal with the challenges of the digital age and the use of artificial intelligence. (AP Photo/Francisco Seco)

Human-centered guidelines for artificial intelligence are essential because "none of the positive things will be achieved if we distrust the technology," said Margrethe Vestager, the executive vice president overseeing the EU's digital strategy.

Under the proposals, which are open for public consultation until May 19, EU authorities want to be able to test and certify the data used by the algorithms that power artificial intelligence in the same way they check cosmetics, cars and toys.

It's important to use unbiased data to train high-risk artificial intelligence systems so they can avoid discrimination, the commission said.

Specifically, AI systems could be required to use data reflecting gender, ethnicity and "other possible grounds of prohibited discrimination."

Other ideas include preserving data to help trace any problems and having AI systems clearly spell out their capabilities and limitations. Users should be told when they're interacting with a machine and not a human while humans should be in charge of the system and have the final say on decisions such as rejecting an application for welfare benefits, the report said.

EU leaders said they also wanted to open a debate on when to allow facial recognition in remote identification systems, which are used to scan crowds to check people's faces to those on a database. It's considered the "most intrusive form" of the technology and is prohibited in the EU except in special cases.

Zuckerberg meets EU officials as bloc's new tech rules loom

Standalone system produces water from the air, even in desert regions

by Kevin Hattori, Technion - Israel Institute of Technology

Researchers at the Technion have developed a standalone system that produces water from the air, even in desert regions. The innovative system is capable of providing water to small and isolated communities, without the need to transport water for long distances.

According to estimates by the World Health Organization (WHO), about 13% of the world's population will suffer from insufficient availability of drinking water by 2025. For this reason, access to freshwater is one of the 17 Sustainable Development Goals (SDGs) adopted by the United Nations in 2015. This goal was the motivation for developing a standalone system for producing water from the air.

The technology was developed by Professor David Broday and Professor Eran Friedler from the Environmental, Water and Agricultural Engineering Division of the Technion Faculty of Civil and Environmental Engineering, and the Stephen and Nancy Grand Water Research Institute (GWRI). It is the first technology of its kind in the world: an energy-efficient system for producing clean water from the air. Unlike the existing technology, the Technion researchers' system is based on a two-stage cyclic process: separation of moisture from the air by absorption using a highly concentrated saline solution, and separation of the moisture from the desiccant under and condensing the vapor under sub-atmospheric pressure conditions.

Credit: Technion - Israel Institute of Technology

"Besides being energy efficient, the new technology offers an additional advantage: as part of the process the water undergoes also pollutant removal processes," said Prof. Broday. "Our technology turns water into a commodity as it enables water to be produced anywhere in the world, without being dependent upon existing sources of liquid water. The prototype we have built demonstrates that the system works as expected and we currently work toward turning it into a commercial product."

"Existing technologies work simply as "reverse" air conditioners, by cooling the whole air mass entering the system in order to condense the moisture," said Prof. Friedler. "This 'direct cooling' approach is energetically inefficient, since such systems waste much of their energy requirements on cooling about 97% of the air volume, which is non-condensable. The new technology involves cooling of only the moisture that has been extracted from the air, significantly reducing the amount of energy required to produce water."

"We are not competing with desalination," explained Prof. Broday. "Israel is a developed nation situated near the sea and can supply all its water needs through desalination systems. Among other reasons, this is because Israel is a relatively small country and a significant portion of the population lives along the coast, such that water does not need to be transported over long distances. In contrast, transporting desalinated water to communities situated far from the coast is very expensive due to the need for extremely long pipelines. Herein lies the advantages of the new technology." The system is particularly relevant for small and isolated communities that are located far from fresh- or salty- water sources, as it can produce water where it is most needed.

According to Prof. Friedler, "in addition to being an essential component of life, water also influences other important aspects, among them individual and community health and even the empowerment of women. In many places, young girls do not attend school because they are busy providing water for the family. Even as adults, women devote hours to transporting water. Furthermore, access to water is a central factor in bloody confrontations in arid regions nowadays, and constitutes one of the foremost motives for immigration. In such conflict zones, the risk of children dying from polluted water is 20 times higher than dying due to violent acts."

Saving water when the sun shines

Can magic mushrooms and LSD treat depression and anxiety? Scientists are optimistic.

by Bethany Ao

When Marc Morgan tried lysergic acid diethylamide, better known as acid or LSD, for the first time as a teenager, he noticed that he could emotionally disconnect from traumatic memories of the sexual abuse he had suffered as a child.

"It allowed me to dissociate from the sharp pain that a lot of these memories can bring up, which caused me to shy away from processing them," said Morgan, who has post-traumatic stress disorder (PTSD) as a result of the abuse. "I was able to confront the topic in a more analytical way that felt healthier."

Years later, Morgan learned about microdosing—taking tiny portions of psychedelic substances, as little as a twentieth of a recreational dose, to get positive effects, like more focus and emotional balance, without negatives like hallucinations and disorientation. He realized that taking small doses allowed him to process his emotions without the stronger, visual effects and looping thoughts.

"It's basically like taking a cup of coffee," said Morgan, now 30. He said that he takes a full dose once or twice a year, and microdoses about four times a year. "You're just able to be a little more free and a little more honest with your emotions without breaking down. There's more of a mental clarity."

Morgan, who has lived in Philadelphia for the past decade, is part of a group of people who use both full doses and microdoses of psychedelic substances to process trauma, and better deal with depression. For some, it's because conventional antidepressants haven't worked for them. Others choose psychedelics because it's a more affordable option than therapy or medication.

However, medical experts don't recommend self-medicating.

"For people interested in a treatment who can't get into a trial, this is not the only thing out there," said Matthew Johnson, an associate professor of psychiatry and behavioral sciences at Johns Hopkins University who has studied psychedelics for over 15 years. "It's one promising thing, and it's important for people to stay in treatment."

In recent months, the use of psychedelics for treatment-resistant depression, anxiety and PTSD—meaning patients do not respond to medication or therapy—has become a hot topic in the mental health field. The FDA approved a nasal spray for treatment-resistant depression (TRD) last March, which uses a derivative of the hallucinogenic ketamine called esketamine. It is the first new antidepressant in decades. (It's currently offered at a handful of clinics in the Philadelphia area.)

In November, the FDA gave psilocybin, a hallucinogenic compound found in magic mushrooms, its second "breakthrough therapy" designation in just over a year. The designation fast-tracks the development and review of drugs.

In a 2017 study of psilocybin and depression, researchers at Imperial College London gave psilocybin therapy to 20 patients with treatment-resistant depression, who reported benefits as long as five weeks after treatment. The study found that psilocybin decreased activity in the amygdala, which processes emotions like fear and anxiety.

"We know that when someone is on a therapeutic dose of a psychedelic, there's a dramatic increase in communication across brain areas," Johnson said. "My theory is that what we're seeing with psychedelic therapy is more like what we normally associate with talk therapy. Psychedelic therapy prompts a therapeutic process, and people learn something by transcending their sense of self and getting out of their own way."

Much less is known about the science behind microdosing psychedelic substances, but a 2019 study by researchers at the University of California-Davis found that the practice can provide relief for symptoms of depression and anxiety in rats.

Additionally, a 2019 survey of more than 1,000 people from across the world who microdosed on LSD found that repeated microdoses were followed by "improvements in negative moods, especially depression" as well as increased positive moods and energy levels.

"There really hasn't been substantiation of the claimed benefits of so-called microdoses," Johnson said. "That's not to say the claimed benefits aren't possible."

The benefits people feel from microdosing might be from a combination of a strong placebo effect and some possible benefit from "tinkering with the serotonin system," Johnson said. But he's open to the potential benefits of microdosing, particularly for depression.

As a result of their research on how psychedelics can be used to help smokers and cancer patients, Johnson and others at Johns Hopkins have suggested that psilocybin's FDA classification should be changed from Schedule I, which means that it has no known medical benefit, to Schedule IV, similar to prescription drugs.

Victor Pablo Acero, a 24-year-old bioengineering doctoral candidate and executive director of the Penn Society for Psychedelic Science, said that accepting both full doses and microdoses as mental health treatments is an important step in destigmatizing the substances.

"Having a mystical experience is correlated with actually getting more clinical effects," Acero said. "Microdosing doesn't recapitulate the mystical experience or ego death. Also psychedelic use ... does not magically heal you, you have to put in work and effort to integrate your experience."

Acero said that he became interested in psychedelics once he began reading research papers about how the substances can be used in clinical settings. But he said that research in this area is still lacking.

"Funding is nonexistent," Acero said. "Scientists are having to argue that they need funding to study the medical purposes of a substance that's classified as having no medical purposes."

Most people suffering from treatment-resistant depression, anxiety or PTSD won't be able to access the new treatments for at least a few years, as research groups run clinical trials. The trials have a limited number of spaces ? - the Usona Institute, a nonprofit medical research group, recruited just 80 participants for a study that's part of their Phase 2 clinical trial for psilocybin. Similarly, LSD is being evaluated in a Phase 2 clinical trial as a treatment for depression in Switzerland. MDMA, better known as ecstasy or molly, is currently in a Phase 3 large-scale clinical trial for PTSD. Upon FDA approval, the SoundMind Center will open in Cedar Park, offering MDMA-assisted psychotherapy to populations with higher rates of PTSD.

While patients wait, self-medication without the aid of a therapist or medical professional is much more common, although it is not recommended. Johnson said that there are risks to psychedelic therapy for people with existing psychotic disorders, like schizophrenia.

"Even if this stuff is approved, it's not going to work for everyone," Johnson said.

Aysha Ali, who struggles with depression and anxiety, began using full doses and microdoses of magic mushrooms about two years ago. Ali, 21, said antidepressants caused side effects like appetite loss, decreased libido and nausea. She also found that mushrooms are more accessible and cheaper for her.

"It's definitely easier to go to bed at night," said Ali, who lives in Wilmington, Del. and works in King of Prussia. "I'm a little more focused, and I feel like I can smile and giggle in the moment. I can feel myself going through my day a little bit better, and the days after feel so much better."

She said that it refreshes her brain and allows her to wake up with a positive attitude.

"It helps me see that I'm not going to be stuck where I am," Ali said. "It's not a cure for everything, but the scientific information we're getting now is helping people get out of this mindset of, 'This is bad.'"

Mike Allebach, a photographer who lives in Montgomery County, first learned about magic mushrooms for mental health through a New York Times article last year.

"It didn't really quite match up with my understanding of mushrooms," said Allebach, 37.

Allebach, who was struggling with depression when he read the article, said that he later tried magic mushrooms in California, where psilocybin mushrooms are decriminalized in Oakland and Santa Cruz. The trip brought him out of his depression. Since coming home, Allebach uses breath work and meditation to maintain his mental health.

"As a society, we're in a place where the new rich is feeling calm and having peace. And if antidepressants don't work for someone, this could be great for someone who wants to be happy again and work on themselves," he said.

Psychedelic drugs could help treat PTSD

Carrots plus sticks: Study looks at what works to reduce low-value care

by University of Michigan

The old story of a farmer trying to get a stubborn mule to pull a wagon by dangling a carrot in front of its nose, or hitting its rump with a stick, may not seem to have much to do with the practice of medicine.

But a new study suggests that when it comes to making the best use of health care dollars, it will take a combination of carrots and sticks to move things forward.

The study looks at the effects of two initiatives that aimed to reduce the use of two blood tests that experts consider "low value" for most patients: Routine vitamin D tests, and an unnecessary thyroid test for tracking thyroid hormone levels.

After an organization that advises the health care system in Ontario, Canada reported in 2010 that population-based Vitamin D screening does not improve outcomes, the province's health plan for all residents declared it wouldn't pay for low-value vitamin D tests.

Soon after, the rate of testing dropped nearly 93 percent, the study shows. Patients who had a condition or medication that might lower their vitamin D levels could still get tested.

But in the U.S., where no such payment change took place, 2.6 million unnecessary vitamin D screening tests happened in just one year, according to the researchers from the University of Michigan, University of Toronto and VA Ann Arbor Healthcare System who published the new findings in JAMA Internal Medicine.

A few years later, as part of an education campaign called Choosing Wisely, physician professional societies issued recommendations on when not to use Vitamin D and T3 testing. And while use of the test in Ontario dropped an additional 4.5%, the use in U.S. patients covered by Veterans Health benefits or commercial insurance dropped about 14%.

"Our study found small reductions in the use of unnecessary vitamin D screenings in response to recommendations from the Choosing Wisely campaign, but much greater reductions in Ontario when recommendations were complemented by policy change," says Eve Kerr, M.D., M.P.H., senior author of the new paper and a professor in the U-M Department of Internal Medicine. "The biggest lesson is that while recommendations alone can work to reduce low value care, recommendations have greater impact when they are reinforced by changes to policy and practice."

Improving value

Kerr heads a program at the U-M Institute for Healthcare Policy and Innovation called the Michigan Program on Value Enhancement. She and her colleagues used the same Choosing Wisely guideline to build an alert for clinicians who had ordered a vitamin D test of low potential value into the electronic health record at Michigan Medicine, U-M's academic medical center.

In 2018, they reported that this guideline-based "carrot" had led to a positive and sustained change in orders for low-value vitamin D tests.

James Henderson, Ph.D., the first author of the new paper, assistant director of MPrOVE and a data science consultant at U-M's Consulting for Statistics, Computing and Analytics Research unit, notes that the new paper's findings show that Choosing Wisely recommendations for T3 testing did not appear to have had the desired impact.

T3 testing, which is no longer recommended for patients with known thyroid issues because a test called TSH is more accurate, did not decline in either the U.S. or Canada after Choosing Wisely guidelines were issued. In fact, in the study population of U.S. patients with private insurance, the rate of testing actually went up slightly.

Handle with care

Kerr, Henderson and their colleagues from IHPI and the VA Center for Clinical Management Research note that policy decisions for low-value care—including payment changes—must be made with care, to avoid problems with access to that type of care for patients who could benefit.

For instance, the Ontario payment change exempted patients who have bone or digestive disorders that can change vitamin D levels, and patients who take certain medications that can change vitamin D absorption from food and supplements.

"Payment policies are not the only effective means for reducing low-value care," says Kerr. "Indeed, sometimes restricting payment may be too blunt an approach and could lead to underuse."

She adds, "Other effective policies that can be coupled with recommendations include population based education programs, communication approaches to help patients and physicians make more patient-centered decisions, decision support for doctors about low-value care, and most importantly, culture change initiatives that emphasize the responsibility of health care institutions, clinicians, and patients to provide and seek high-value, evidence-based care while avoiding low-value services."

More awareness of Choosing Wisely campaign needed for nurses

More information: James Henderson et al, Comparison of Payment Changes and Choosing Wisely Recommendations for Use of Low-Value Laboratory Tests in the United States and Canada, JAMA Internal Medicine (2020). DOI: 10.1001/jamainternmed.2019.7143

Simple, fuel-efficient rocket engine could enable cheaper, lighter spacecraft

by Sarah McQuate, University of Washington

It takes a lot of fuel to launch something into space. Sending NASA's Space Shuttle into orbit required more than 3.5 million pounds of fuel, which is about 15 times heavier than a blue whale.

But a new type of engine—called a rotating detonation engine—promises to make rockets not only more fuel-efficient but also more lightweight and less complicated to construct. There's just one problem: Right now this engine is too unpredictable to be used in an actual rocket.

Researchers at the University of Washington have developed a mathematical model that describes how these engines work. With this information, engineers can, for the first time, develop tests to improve these engines and make them more stable. The team published these findings Jan. 10 in Physical Review E.

"The rotating detonation engine field is still in its infancy. We have tons of data about these engines, but we don't understand what is going on," said lead author James Koch, a UW doctoral student in aeronautics and astronautics. "I tried to recast our results by looking at pattern formations instead of asking an engineering question—such as how to get the highest performing engine—and then boom, it turned out that it works."

A conventional rocket engine works by burning propellant and then pushing it out of the back of the engine to create thrust.

To start the reaction, propellant flows in the gap between the cylinders, and, after ignition, the rapid heat release forms a shock wave (starts at 11 seconds). After this start-up phase, a number of stable combustion pulses form that continue to consume available propellant. Credit: James Koch/University of Washington

"A rotating detonation engine takes a different approach to how it combusts propellant," Koch said. "It's made of concentric cylinders. Propellant flows in the gap between the cylinders, and, after ignition, the rapid heat release forms a shock wave, a strong pulse of gas with significantly higher pressure and temperature that is moving faster than the speed of sound.

"This combustion process is literally a detonation—an explosion—but behind this initial start-up phase, we see a number of stable combustion pulses form that continue to consume available propellant. This produces high pressure and temperature that drives exhaust out the back of the engine at high speeds, which can generate thrust."

Conventional engines use a lot of machinery to direct and control the combustion reaction so that it generates the work needed to propel the engine. But in a rotating detonation engine, the shock wave naturally does everything without needing additional help from engine parts.

"The combustion-driven shocks naturally compress the flow as they travel around the combustion chamber," Koch said. "The downside of that is that these detonations have a mind of their own. Once you detonate something, it just goes. It's so violent."

To try to be able to describe how these engines work, the researchers first developed an experimental rotating detonation engine where they could control different parameters, such as the size of the gap between the cylinders. Then they recorded the combustion processes with a high-speed camera. Each experiment took only 0.5 seconds to complete, but the researchers recorded these experiments at 240,000 frames per second so they could see what was happening in slow motion.

After the initial shock wave, stable pulses of combustion continue to consume available propellant. Previously researchers didn't understand how a specific number of pulses formed and why they can sometimes merge into one pulse, but this mathematical model developed by University of Washington researchers can help explain the underlying physics. Credit: Koch et al./Physical Review E

From there, the researchers developed a mathematical model to mimic what they saw in the videos.

"This is the only model in the literature currently capable of describing the diverse and complex dynamics of these rotating detonation engines that we observe in experiments," said co-author J. Nathan Kutz, a UW professor of applied mathematics.

The model allowed the researchers to determine for the first time whether an engine of this type would be stable or unstable. It also allowed them to assess how well a specific engine was performing.

"This new approach is different from conventional wisdom in the field, and its broad applications and new insights were a complete surprise to me," said co-author Carl Knowlen, a UW research associate professor in aeronautics and astronautics.

Right now the model is not quite ready for engineers to use.

"My goal here was solely to reproduce the behavior of the pulses we saw—to make sure that the model output is similar to our experimental results," Koch said. "I have identified the dominant physics and how they interplay. Now I can take what I've done here and make it quantitative. From there we can talk about how to make a better engine."

More efficient satellite launch platform on the horizon

More information: James Koch et al, Mode-locked rotating detonation waves: Experiments and a model equation, Physical Review E (2020). DOI: 10.1103/PhysRevE.101.013106

Fifty years of data show new changes in bird migration

by American Ornithological Society

A growing body of research shows that birds' spring migration has been getting earlier and earlier in recent decades. New research from The Auk: Ornithological Advances on Black-throated Blue Warblers, a common songbird that migrates from Canada and the eastern U.S. to Central America and back every year, uses fifty years of bird-banding data to add another piece to the puzzle, showing that little-studied fall migration patterns have been shifting over time as well.

Loyola Marymount University's Kristen Covino and her colleagues used data housed at the USGS Bird Banding Laboratory on migrating Black-throated Blue Warblers between 1965 and 2015. Across the United States, researchers working with this program safely capture migrating birds, collect data on them, and fit them with metal leg bands with unique codes that allow them to be identified if they're captured again. Analyzing almost 150,000 individual records, Covino and her colleagues found that the timing of the birds' spring migration has advanced over the last fifty years, with early migrants passing through banding sites approximately one day earlier each decade. Crucially, their data also covered fall migration, which has been less well-studied, and found that while the timing of the peak of fall migration hasn't changed, fall migration takes longer today than it did fifty years ago.

The North American Bird Banding Program is one of the most expansive historical datasets on migratory birds, including records for over 38 million songbirds banded since 1960. "My coauthor Sara Morris and I were already working together on another paper on Blackpoll Warblers using data we'd requested from banding stations across North America. We wanted to take a similar large-scale approach for this study, but we wanted to demonstrate that we could do this approach with data that is completely available from the Bird Banding Lab," says Covino. "We selected Black-throated Blue Warblers because it's relatively straightforward to determine their age and sex, which means that the data this species generates are both accurate and powerful."

Although the researchers emphasize that their findings can't be explicitly linked to climate change without incorporating climate or environmental data, they believe similar methods could be useful for tracking the effects of climate change on birds. "The protraction of fall migration means that the season is getting longer overall, but it could also mean that the breeding season may be shifting, ending earlier for some individuals but later for others. To determine what this means in the context of breeding season shifts in timing, additional studies that incorporate both arrival on the breeding grounds and, importantly, departure from them are needed," says Covino. "More studies of these patterns of fall migration timing and, even more so, both spring and fall migration timing across years are needed to gain the complete picture of how species are changing migration timing."

Spring migration is now earlier in European and North American birds

More information: "Seasonally-specific changes in migration phenology across 50 years in the Black-throated Blue Warbler" academic.oup.com/auk/article-l … i/10.1093/auk/ukz080.

Cracks make historical paintings less vulnerable to environmental variations

by BioMed Central

Historical wood panel paintings with developed craquelure patterns—networks of fine cracks in the paint- are significantly less vulnerable to environmental variations than previously assumed, according to a study in the open access journal Heritage Science. The findings offer a potential explanation as to why heavily cracked historical paintings remain stable in environments far from 'ideal' museum conditions.

Painted wood is among the most precious and frequently exhibited category of heritage objects and among the most vulnerable to relative humidity and temperature fluctuations.

A team of researchers at the Polish Academy of Sciences, Université de Strasbourg, France and Yale University, USA investigated changes in susceptibility to fracture for the most brittle component of a wood painting—the ground layer, or gesso, a mixture of animal glue and white pigment that is applied between the wooden support and the paint. The gesso is strained when wood expands due to increasing humidity or contracts due to desiccation, which can leads to cracking. Knowledge of this as well as development of technical capabilities to control environment precisely have led to stringent climate control specifications for museums, both in temperature (21 or 22°C) and humidity (45-55%).

Lukasz Bratasz, the corresponding author said: "The current environmental standards for the display of painted wood allow for only moderate variations of relative humidity. The safe range was determined based on laboratory testing of when cracks start to form in new, undamaged material. However, this does not reflect the physical reality of paintings as they age and complex craquelure patterns form. Our research more accurately reflects that physical reality, accounting for changes in the susceptibility to environmental stresses as paintings age."

To investigate the development of cracks in gesso layers subject to different environmental conditions over time, the authors designed specimens of two wooden panels, which they joined with gessoes prepared according to traditional recipes. The specimens were stored at 25°C and relative humidity of 30, 50, 75 and 90% for two weeks before being subjected to splitting test, which measure how resistant gessoes are to cracking.

Using computer tomography to scan historic samples of panel painting, the authors determined the size of existing flaws in the gesso at which new cracks initiate. Those measurements were then used in a computer model of a panel painting to simulate further crack formation. Factoring in the elasticity of the materials and moisture expansion of wood, the authors found that the stress on the gesso decreased as the number of cracks increased over time.

Lukasz Bratasz said: "Stress on the gesso occurs in the areas between cracks. The larger these areas are, the more easily cracks will form. As cracks multiply and the spaces between them become smaller, stress decreases up to a point where, finally, no new cracks will form."

The authors caution that their conclusions are valid for paintings with 'opened' cracks. If cracks are filled in during conservation treatment or varnishing, the vulnerability of a painting to the environment may increase.

Lukasz Bratasz said: "Our findings offer a potential explanation as to why historical panel paintings with developed craquelure patterns remain stable, even if the environmental conditions they are stored in are far from ideal. We hope that this knowledge may contribute to development and acceptance of more moderate-cost climate control strategies in historic buildings and museums, especially ones that may have limited potential for tighter climate control."

Climate systems in museums appear to be too strictly regulated

More information: Fracture saturation in paintings makes them less vulnerable to environmental variations in museums Bratasz et al. Heritage Science 2020 DOI: 10.1186/s40494-020-0352-0

Eliminating viruses in our food with cranberries and citrus fruit

by Institut national de la recherche scientifique

Fresh produce is a major vehicle for noroviruses, a group of viruses that are the most common cause of gastroenteritis in developed countries. However, the viruses are quite resistant to cold pasteurization treatments such as irradiation, which are used to destroy bacteria, moulds, parasites, and insects. The irradiation process uses gamma rays or X-rays to destroy these viruses but at the dose needed to eliminate them, it can affect the physicochemical properties of fresh produce.

Professor Monique Lacroix, a researcher at Institut National de la Recherche Scientifique (INRS), has developed an edible coating based on cranberry juice and citrus extract that makes noroviruses more sensitive to gamma irradiation, making it possible to eliminate them while preserving the quality of food, all without risk to consumers.

A fruit extract spray

The idea is to spray fresh produce such as lettuce or strawberries and then treat it with cold pasteurization such as irradiation. The organic acids and polyphenols in cranberry juice and citrus extract would alter the viral protein and help inhibit its activity.

"Noroviruses usually require an irradiation dose of three kilograys (kGy), but we have shown that the treatment time is reduced by half with this fruit mixture spray, which acts as a natural antimicrobial. Using these natural antimicrobials prevents cell breakdown or brown discolouration," reports Monique Lacroix, lead author on the study whose results were published online on February 12 in the Journal of Applied Microbiology.

Professor Lacroix's team is the first to test the cranberry juice and citrus extract mixture in a combined treatment. "Both the juice and extract have the ability to remove noroviruses when used alone, but when combined with cold pasteurization in the same treatment, the fruit concentrations required are significantly lower," says the food science expert.

Norovirus Contamination

Norovirus contamination can occur before and after harvest. Contaminated water runoff from fields can bring in fecal matter. Food can be contaminated by infected people who handle it.

"Unlike bacteria, noroviruses do not multiply on food. They are deposited there and remain there until a human being is infected," says Alexandra Gobeil, first author of the study and a recent master's graduate in Applied Microbiology at INRS.

Monique Lacroix and her team have tested the coating on lettuce, one of the most fragile vegetables in terms of preservation. She hopes to eventually develop a partnership with the food industry to test combinations of treatments involving natural fruit extracts and cold pasteurization (e.g., UV-C, X-ray, gamma ray, or ozonation) on a commercial scale.

Lemon juice and human norovirus

More information: A. Gobeil et al, Radiosensitivity increase in FCV‐F9 virus using combined treatments with natural antimicrobials and γ‐irradiation, Journal of Applied Microbiology (2020). DOI: 10.1111/jam.14596

Study of stone-age engravings suggests they were created with aesthetic intention

by Bob Yirka , Phys.org

A team of researchers from Denmark, Australia and South Africa has found evidence that suggests stone-age etchings found at two sites in South Africa were created with aesthetic intention and that they evolved over time. In their paper published in Proceedings of the National Academy of Sciences, the group describes experiments they carried out with volunteers looking at reproductions of stone-age engravings and what they learned from them.

Back in 1973, researchers found ostrich eggshell water containers with images etched onto them in the Diepkloof Rock Shelter in western South Africa. Subsequent testing showed the containers to be from approximately 60,000 years ago. Not far away, archaeologists began excavating Blombos Cave in 1991, and during that work, discovered engraved ochre and bones. They were dated to between 100,000 and 70,000 years ago. Notably, the etchings at both sites were made over very long periods of time, allowing researchers to study their evolution. As time passed, the human brain became more sophisticated, allowing humans to express themselves in more tangible form through etchings. In this new effort, the researchers created drawings of the etchings found in both locations and studied them by showing them to volunteers.

In all, the researchers carried out five experiments designed to test the sophistication of the stone-age drawings. The first involved showing volunteers a drawing in one eye and a flickering pattern in the other eye—the researchers timed how long it took the volunteers to identify patterns in the drawings. The images created more recently were more quickly identified as such.

Another test involved showing volunteers two drawings and asking them which they thought was more likely made intentionally—again, those made more recently were identified as likely being intentional.

A third test involved showing volunteers a drawing for just three seconds and then asking them to reproduce it on a piece of paper. Once again, the volunteers were better able to reproduce those images that were created most recently. The fourth test involved asking the volunteers to guess which of two drawings they were shown came from the same site—and once again, they were more accurate when looking at more recently created images. The final test involved asking the volunteers which of two drawings they thought were created more recently; they chose those that had been created more recently. The researchers suggest that the volunteer answers indicated that the engravings were created with aesthetic intention, and clearly evolved in sophistication over time.

Oldest known animal drawing found in remote Indonesian cave

More information: Kristian Tylén el al., "The evolution of early symbolic behavior in Homo sapiens," PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.1910880117

Journal information: Proceedings of the National Academy of Sciences

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