Culture

Since its beginnings, quantum mechanics hasn't ceased to amaze us with its peculiarity, so difficult to understand. Why does one particle seem to pass through two slits simultaneously? Why instead of specific predictions can we only talk about evolution of probabilities? According to theorists from universities in Warsaw and Oxford, the most important features of the quantum world may result from the special theory of relativity, which until now seemed to have little to do with quantum mechanics.

Since the arrival of quantum mechanics and the theory of relativity, physicists have lost sleep over the incompatibility of these three concepts (three, since there are two theories of relativity: special and general). It has commonly been accepted that it is the description of quantum mechanics that is the more fundamental and that the theory of relativity that will have to be adjusted to it. Dr. Andrzej Dragan from the Faculty of Physics, University of Warsaw (FUW) and Prof. Artur Ekert from the University of Oxford (UO) have just presented their reasoning leading to a different conclusion. In the article "The Quantum Principle of Relativity", published in the New Journal of Physics, they prove that the features of quantum mechanics determining its uniqueness and its such non-intuitive exoticism - accepted, what's more, on faith (as axioms) - can be explained within the framework of the special theory of relativity. One only has to decide on a certain rather unorthodox step.

Albert Einstein based the special theory of relativity on two postulates. The first is known as the Galilean principle of relativity (which, please note, is a special case of the Copernican principle). This states that physics is the same in every inertial system (i.e., one that is either at rest or in a steady straight line motion). The second postulate, formulated on the result of the famous Michelson-Morley experiment, imposed the requirement of a constant velocity of light in every reference system.

"Einstein considered the second postulate to be crucial. In reality, what is crucial is the principle of relativity. Already in 1910 Vladimir Ignatowski showed that based only on this principle it is possible to reconstruct all relativistic phenomena of the special theory of relativity. A strikingly simple reasoning, leading directly from the principle of relativity to relativism, was also presented in 1992 by Professor Andrzej Szymacha from our faculty," says Dr. Dragan.

The special theory of relativity is a coherent structure that allows for three mathematically correct types of solutions: a world of particles moving at subluminal velocities, a world of particles moving at the velocity of light and a world of particles moving at superluminal velocities. This third option has always been rejected as having nothing to do with reality.

„We posed the question: what happens if - for the time being without entering into the physicality or non-physicality of the solutions - we take seriously not part of the special theory of relativity, but all of it, together with the superluminal system? We expected cause-effect paradoxes. Meanwhile, we saw exactly those effects that form the deepest core of quantum mechanics," say Dr. Dragan and Prof. Ekert.

Initially, both theorists considered a simplified case: space-time with all three families of solutions, but consisting of only one spatial and one time dimension (1+1). A particle at rest in one system of solutions seems to move superluminally in the other, which means that superluminosity itself is relative.

In a space-time continuum constructed this way, non-deterministic events occur naturally. If in one system at point A there is generation of a superluminal particle, even completely predictable, emitted towards point B, where there is simply no information about the reasons for the emission, then from the point of view of the observer in the second system events run from point B to point A, so they start from a completely unpredictable event. It turns out that analogous effects appear also in the case of subluminal particle emissions.

Both theorists have also shown that after taking into account superluminal solutions, the motion of a particle on multiple trajectories simultaneously appears naturally, and a description of the course of events requires the introduction of a sum of combined amplitudes of probability that indicate the existence of superposition of states, a phenomenon thus far associated only with quantum mechanics.

In the case of space-time with three spatial dimensions and one time dimension (3+1), that is, corresponding to our physical reality, the situation is more complicated. The principle of relativity in its original form is not preserved - the subluminal and superluminal systems are distinguishable. However, the researchers noticed that when the principle of relativity is modified to the form: "The ability to describe an event in a local and deterministic way should not depend on the choice of an inertial reference system", it limits the solutions to those in which all the conclusions from the consideration in (1+1) space-time remain valid.

"We noticed, incidentally, the possibility of an interesting interpretation of the role of individual dimensions. In the system that looks superluminal to the observer some space-time dimensions seem to change their physical roles. Only one dimension of superluminal light has a spatial character - the one along which the particle moves. The other three dimensions appear to be time dimensions," says Dr. Dragan.

A characteristic feature of spatial dimensions is that a particle can move in any direction or remain at rest, while in a time dimension it always propagates in one direction (what we call aging in everyday language). So, three time dimensions of the superluminal system with one spatial dimension (1+3) would thus mean that particles inevitably age in three times simultaneously. The ageing process of a particle in a superluminal system (1+3), observed from a subluminal system (3+1), would look as if the particle was moving like a spherical wave, leading to the famous Huygens principle (every point on a wavefront can be treated itself as a source of a new spherical wave) and corpuscular-wave dualism.

"All the strangeness that appears when considering solutions relating to a system that looks superluminal turns out to be no stranger than what commonly accepted and experimentally verified quantum theory has long been saying. On the contrary, taking into account a superluminal system, it is possible - at least theoretically - to derive some of the postulates of quantum mechanics from the special theory of relativity, which were usually accepted as not resulting from other, more fundamental reasons," Dr. Dragan concludes.

For almost a hundred years quantum mechanics has been awaiting a deeper theory to explain the nature of its mysterious phenomena. If the reasoning presented by the physicists from FUW and UO stands the test of time, history would cruelly mock all physicists. The "unknown" theory sought for decades, explaining the uniqueness of quantum mechanics, would be something already known from the very first work on quantum theory.

Physics and Astronomy first appeared at the University of Warsaw in 1816, under the then Faculty of Philosophy. In 1825 the Astronomical Observatory was established. Currently, the Faculty of Physics' Institutes include Experimental Physics, Theoretical Physics, Geophysics, Department of Mathematical Methods and an Astronomical Observatory. Research covers almost all areas of modern physics, on scales from the quantum to the cosmological. The Faculty's research and teaching staff includes ca. 200 university teachers, of which 87 are employees with the title of professor. The Faculty of Physics, University of Warsaw, is attended by ca. 1000 students and more than 170 doctoral students.

The risk for violent clashes increases after weather extremes such as droughts or floods hit people in vulnerable countries, an international team of scientists finds. Vulnerable countries are characterized by a large population, political exclusion of particular ethnic groups, and low development. The study combines global statistical analysis, observation data and regional case study assessments to yield new evidence for policy-makers.

"Climate disasters can fuel some smoldering conflicts - this is a worrying insight since such disasters are on the rise," says Jonathan Donges at the Potsdam Institute for Climate Impact Research, Germany, co-author of the paper now published in Global Environmental Change. "Ongoing greenhouse gas emissions from fossil fuels are, if unmitigated, destabilizing our climate. More frequent and more severe weather extremes are one of the effects. The new study adds important evidence and hence robustness to conflict analyses we've done in the past few years."

"One third of all conflict onsets in vulnerable countries" is affected

The numbers are quite staggering. "We find that almost one third of all conflict onsets in vulnerable countries over the recent decade have been preceded by a climate-related disaster within 7 days," says co-author Carl-Friedrich Schleussner from Climate Analytics in Berlin, Germany. "This does, however, not mean that disasters cause conflicts, but rather that disaster occurrence increases the risks of a conflict outbreak." After all, conflict is human-made. The analysis of concrete cases of disaster-conflict co-occurences shows that most such cases are not mere coincidences, but likely linked by causal mechanisms - this is one of the key new findings.

In Mali for instance a severe drought occurred in 2009 after which the militant Al-Qaeda in the Islamic Maghreb exploited the resulting state weakness and desperation of local people to recruit fighters and expand its area of operation. Other examples analyzed include China, the Philippines, Nigeria, and Turkey. India turns out to be the country with the by far highest number of disaster-conflict coincidences. The most surprising result of the study, says co-author Michael Brzoska from the University of Hamburg, was the prevalence of opportunities for armed violence over those related to grievances in post-disaster situations.

"Measures to make societies more inclusive and wealthier are no-regrets options"

"Climate-related disasters may act like a 'threat multiplier' for violent conflicts," explains Tobias Ide from the University of Melbourne. A most important finding of the study is that only countries with large populations, the political exclusion of ethnic groups and relatively low levels of economic development are susceptible to disaster-conflict links. Optimistically, Ide concludes: "Measures to make societies more inclusive and wealthier are, therefore, no-regrets options to increase security in a warming world."

Sustainable energy storage is in great demand. Researchers at Uppsala University have therefore developed an all-organic proton battery that can be charged in a matter of seconds. The battery can be charged and discharged over 500 times without any significant loss of capacity. Their work has been published in the scientific journal Angewandte Chemie.

The researchers have been able to demonstrate that their battery can be easily charged using a solar cell. Charging can also be accomplished without the aid of the advanced electronics that, for example, lithium batteries require. Another advantage of the battery is that it is unaffected by ambient temperature.

"I'm sure that many people are aware that the performance of standard batteries declines at low temperatures. We have demonstrated that this organic proton battery retains properties such as capacity down to as low as -24°C," says Christian Strietzel of Uppsala University's Department of Materials Science and Engineering.

A great many of the batteries manufactured today have a major environmental impact, not least due to the mining of the metals used in them.

"The point of departure for our research has therefore been to develop a battery built from elements commonly found in nature and that can be used to create organic battery materials," explains Christian Strietzel.

For this reason, the research team has chosen quinones as the active material in their battery. These organic carbon compounds are plentiful in nature, among other things occurring in photosynthesis. The characteristic of quinones that researchers have utilised is their ability to absorb or emit hydrogen ions, which of course only contain protons, during charging and discharging.

An acidic aqueous solution has been used as an electrolyte, the vital component that transports ions inside the battery. As well as being environmentally friendly, this also provides a safe battery free from the hazard of explosion or fire.

"There remains a great deal of further development to be done on the battery before it becomes a household item; however, the proton battery we have developed is a large stride towards being able to manufacture sustainable organic batteries in future," says Christian Strietzel.

Open biomass burning (OBB) has a significant impact on regional air quality, especially on the heavy haze pollution in Northeast China (NEC) in recent years. Recent research published in Atmospheric and Oceanic Science Letters provides scholars and decision-makers with a more comprehensive and long-term analysis of the spatiotemporal patterns of OBB in NEC.

By using the MODIS fire and land cover products, Dr Lili Wang from the Institute of Atmospheric Physics, Chinese Academy of Sciences attempted to capture the spatial and temporal distribution of OBB in NEC from 2003 to 2017, as well as the corresponding proportion of fire points in different vegetation types.

The results show the changes in the total number of MODIS fire points in NEC from 2003 to 2017 demonstrated a fluctuating but generally rising trend, with the peak during 2013-2017.

"We found that most fire points concentrated in two key periods, i.e., March-April and October-November. OBB in Heilongjiang Province comprised a major proportion of the total number of fire spots in NEC, and the largest proportion of all fires was in cropland," says Dr Wang.

According to this study, the cumulative emissions of PM2.5, NOx and NH3 from open agricultural burning reached up to 158.46 Gg, 49.50 Gg, and 27.00 Gg in March, April, October, and November during 2013-17, respectively. Significantly, the majority of OBB generally shifted from October-November to March-April for all three provinces and the amount of OBB in March-April was higher than that in October-November during 2016-17.

Dr Wang suggests more effective utilization approaches for crop residue and strict policies should be taken to control the upward trend of crop residue burning in NEC. In addition, prescribed in-situ burning could be an effective straw management strategy if farmers are reluctant to give up this traditional farming method.

Doctors need to pay particular attention to patients with endocrine disorders and diabetes mellitus in relation to COVID-19 infections, say leading endocrinologists.

In an editorial published in the Journal of Clinical Endocrinology & Metabolism, they say data from Wuhan province in China, where the pandemic started, has revealed that patients with diabetes mellitus were over-represented in the group of people who become severely ill and also among those who died.

The endocrinologists, who are experts in hormone-related diseases, say medical teams need to be extra vigilant when they are dealing with this patient group.

According to Diabetes UK, 4.7 million people in the UK have diabetes mellitus.

Paul Stewart, editor in chief of the journal and Professor of Medicine at the University of Leeds, said: "There is early evidence from China that those patients who have endocrinological disorders face additional risks from COVID-19.

"The scientific picture indicates that these people need to self-isolate, to try and reduce the chance of infection in the same way as the background population. There are endocrinological disorders that affect the body's ability to make steroid hormones - or glucocorticoids - to help overcome infection. This might make some patients more vulnerable to the effects of the COVID-19 illness."

Patients with known problems of the adrenal gland are treated with replacement glucocorticoid on a daily basis - such patients who begin to develop symptoms of COVID-19 should double their dose of medication immediately: they should follow their "sick day rules", the protocol they have agreed with their doctor to follow when they feel unwell, until any fever subsides.

However, there are many other patients who take glucocorticoids because of inflammatory diseases. Some of these patients take large doses and that may suppress their immune systems and importantly prevent the body's ability to respond to COVID-19.

Whilst glucocorticoid treatment has no role to play in the treatment of COVID-19 per se, intravenous stress doses should be considered by doctors in any patient previously treated with glucocorticoids who is deteriorating with COVID-19.

These recommendations apply to specific patient groups. People should not change their medication regime without first talking to their doctor.

When do cells decide to divide? For 40 years, the textbook answer has been that this decision occurs in the first phase of a cell's existence - right after a mother cell divides to become daughter cells.

But researchers at CU Boulder have found that it's actually the mother cell that determines if its daughter cells will divide. The finding, explained in a new study out today in Science, sheds new light on the cell cycle using modern imaging technologies, and could have implications for cancer drug therapy treatments.

"We see something different than what's in the textbooks," said Sabrina Spencer, senior author of the paper and assistant professor of biochemistry.

Cells choose to divide based on the amount of mitogens, or growth factors, they sense in their environment. The availability of mitogens drives the signal to proliferate: duplicate cellular contents and divide into two daughter cells. This is all part of the cell cycle.

Cancer cells can enter the cell cycle even if growth factors aren't there, said Spencer. That's part of why they proliferate so much - the cell cycle becomes dysregulated and growth continues unchecked.

Better understanding of why and when cells choose to proliferate, could help scientists tailor or expand the timing of cancer drug therapies.

In their experiments, the researchers found that rather than daughter cells deciding on their own whether to divide, they committed to another cell cycle or not immediately after division of the mother cell. This implies the decision was made in the previous cell cycle, because the daughter cells were already born on one path or another, according to Spencer.

"That got us thinking that maybe all the sensing of the environment is actually happening in the mother cell cycle," said Spencer.

Previous textbook experiments had to first remove all growth factors in order to synchronize the cells' cycling, which perturbs cell cycle behavior. But this new research used time lapse microscopy and cell tracking technologies, which allowed the scientists to film cells doing their own thing, on their own time.

"Doing the experiment this way led to very different results," said Spencer.

The researchers tracked thousands of cells across 48 hours, using computational cell tracking - which can track the same cell through hundreds of sequential images.

Even 10 years ago, very few labs could track cells even for a couple of hours, said Spencer.

Signals and memory

Their next question was: when in the mother cell cycle does a cell decide if its daughter cells will divide?

To answer this, the researchers removed and replaced the growth factors - which give the signal for the cell to divide - for several hours at different phases in the mother cell cycle.

They found that the longer these growth factors were removed in the mother cell, the less likely the daughter cells were to divide. If the growth factors were removed for more than nine hours, none of the daughter cells ended up dividing.

"We found that no matter when you blocked this signaling, cells can sense it," said Mingwei Min, first author and postdoctoral researcher in the Department of Biochemistry and BioFrontiers Institute. "And not only can they sense it, they can remember that information for many hours, all the way through to the daughter cell cycle."

If cells are continually sensing growth factor signaling - as this new paper found - instead of only in the first phase of the daughter cycle, cancer drugs may have a longer window than previously believed to provide therapeutic effects.

But how are cells remembering the availability of growth factors? The key lies in a protein known as Cyclin D.

Normally, Cyclin D rises up in the second half of the cell cycle in the mother cell. But when growth factors were removed and replaced in the experiment, there was less Cyclin D at the end of the mother cell cycle, the study found.

And without as much Cyclin D, the daughter cells have less of the thing they need to be able to divide.

"The fact that cells can store memory - or integrate past history - of growth factor availability is a new finding," said Spencer. "The combination of fluorescent sensor design, long-term time-lapse microscopy, and cell tracking is really our forte that enabled this discovery."

New research from Stanford University has found that stress can hinder our ability to develop informed plans by preventing us from being able to make decisions based on memory.

"We draw on memory not just to project ourselves backward into the past but to project ourselves forward, to plan," said Stanford psychologist Anthony Wagner, who is the senior author of the paper detailing this work, published April 2 in Current Biology. "Stress can rob you of the ability to draw on cognitive systems underlying memory and goal-directed behavior that enable you to solve problems more quickly, more efficiently and more effectively."

Combined with previous work from Wagner's Memory Lab and others, these findings could have broad implications for understanding how different people plan for the future - and how lack of stress may afford some people a greater neurologically-based opportunity to think ahead.

"It's a form of neurocognitive privilege that people who are not stressed can draw on their memory systems to behave more optimally," said Wagner, who is the Lucie Stern Professor in the Social Sciences at Stanford's School of Humanities and Sciences. "And we may fail to actually appreciate that some individuals might not be behaving as effectively or efficiently because they are dealing with something, like a health or economic stressor, that reduces that privilege."

Take a virtual walk

The researchers conducted experiments where they monitored participants' behavior and brain activity - via fMRI - as they navigated through virtual towns. After participants became very familiar winding routes in a dozen towns, they were dropped onto one of the memorized paths and told to navigate to a goal location.

To test the effects of stress, the researchers warned some participants that they could receive a mild electric shock, unrelated to their performance, during their virtual rambles. Participants who didn't have to worry about being randomly shocked tended to envision and take novel shortcuts based on memories acquired from prior journeys, whereas the stressed participants tended to fall back on the meandering, habitual routes.

Prior to beginning their trek, the participants were virtually held in place at their starting position. Brain scans from this period showed that the stressed individuals were less likely than their counterparts to activate the hippocampus - a brain structure that would have been active if they were mentally reviewing previous journeys. They also had less activity in their frontal-parietal lobe networks, which allows us to bring neural processes in line with our current goals. Previous work by the researchers had found that stress hinders this neural machinery, making it harder for us to retrieve and use memories.

The researchers believe their new study is the first to show how hippocampal-frontal lobe network disruption takes memory replay offline during a planning session due to stress.

"Its kind of like our brain is pushed into a more low-level thought-process state, and that corresponds with this reduced planning behavior," said Thackery Brown, who was a postdoctoral scholar in the Memory Lab during this research and is lead author of the paper.

Stress and old age

Looking forward, the researchers are especially interested in how the relationship between stress and memory affects older populations, who often experience both health and economic issues. Older people are also more likely to be concerned about memory loss. Together, these combined stressors could contribute to a diminished ability to remember, which could further exacerbate their stress and also impair their ability to deal with it.

Brown has begun conducting studies similar to the virtual navigation experiments with participants between the ages of 65 and 80 to try to better understand how the associations between stress, memory and planning play out in older populations.

"It's a powerful thing to think about how stressful events might affect planning in your grandparents," said Brown, who is now an assistant professor at Georgia Institute of Technology. "It affects us in our youth and as we interact with and care for older members of our family, and then it becomes relevant to us in a different way when we are, ourselves, older adults."

Limited global supplies may scupper proposals to use the antimalarial drugs, chloroquine and hydroxychloroquine, to lessen the symptoms of Covid-19 infection or ward it off altogether, say Italian doctors in a letter published online today in the Annals of the Rheumatic Diseases.

The results of preliminary lab tests have prompted scientists to propose that these drugs be used to treat patients with pneumonia caused by Covid-19 infection. This approach has already been included in Chinese guidelines on how best to manage the disease.

Various studies over the past decade have shown that antimalarial drugs can lessen the impact of viral infections, including Covid-19. And clinical trials are now under way to see whether these drugs might help ward off the disease altogether.

Chloroquine and hydroxychloroquine have been used to treat autoimmune disease, including rheumatic diseases, since the 1940s, and have proved safe and well tolerated in most cases, say the authors.

Side effects are generally mild to moderate, with serious complications, such as retinal and cardiac damage, rare and related to cumulative doses over a long period of time.

There is an ethical issue, however, as there is as yet no hard evidence from clinical trials that these drugs can prevent the spread of Covid-19, they point out.

"Is it permissible to take a controlled risk in the event of a pandemic?" they ask. "In such a case: would it be reasonable to consider antimalarials as primary prophylaxis in healthy subjects living in highest risk regions or, at least, to use them in those testing positive for Covid-19, but still asymptomatic?"

The safety and effectiveness of these drugs makes them good candidates for mass preventive treatment programmes, they add, and scientists seem to be leaning towards adopting this approach.

But, conclude the authors: "If mass prophylaxis was accepted as an option worldwide, this would raise the question of whether there is enough supply of [chloroquine] and [hydroxychloroquine] to support this approach."

The European League Against Rheumatism (EULAR), which co-owns the Annals of the Rheumatic Diseases with BMJ, says that the use of these drugs to tackle Covid-19 could have serious implications for people with rheumatic diseases across Europe.

EULAR President, Professor Iain McInnes, says that global efforts to boost the evidence base for the use of these antimalarial drugs to treat Covid-19 are extremely welcome.

But he adds: "EULAR is concerned, however, that the diversion of drug supplies away from people with rheumatic and musculoskeletal diseases may compromise the health of this important and sizeable group of patients in Europe and beyond."

EULAR's patient membership group (PARE) is now calling on the manufacturers of these drugs to rapidly increase production to meet the projected surge in demand.

"A balanced approach that meets the imperatives of the ongoing pandemic, but which also takes account of the needs of patients already taking these drugs is essential," insists Professor McInnes.

New research has found that allotment gardening promotes positive body image, which measures someone's appreciation of their own body and its functions, and an acceptance of bodily imperfections.

The study, published in the journal Ecopsychology and led by Professor Viren Swami of Anglia Ruskin University (ARU), involved 84 gardeners from 12 urban allotment sites in north London.

Through a series of questionnaires, it found that the gardeners had significantly higher levels of body appreciation, significantly higher levels of body pride, and significantly higher levels of appreciation for their body's functionality, compared to a group of 81 non-gardeners, recruited from the same area of London.

The study also discovered that the longer period of time the participants spent gardening, the larger the improvement in positive body image when they left their allotment.

Previous research has shown that gardening is associated with improved psychological wellbeing and physical health. This new study adds to previous work by Professor Swami demonstrating that exposure to natural environments helps to promote positive body image.

Viren Swami, Professor of Social Psychology at Anglia Ruskin University (ARU), in Cambridge, and Perdana University, in Malaysia, said: "Positive body image is beneficial because it helps to foster psychological and physical resilience, which contributes to overall wellbeing.

"My previous research has shown the benefits of being in nature more generally, but increasing urbanisation has meant that many people now have less access to nature.

"The findings from this new study are important because they specifically show the significant benefits of spending time on allotments, which are typically quite small patches of green space in otherwise mainly urban environments.

"Ensuring that opportunities for gardening are available to all people is, therefore, vital and may help to reduce the long-term cost burden on health services. One way to achieve this, beyond policies that ensure access to nature for all citizens, would be through the provision of dedicated and sustained community allotment plots."

A group of scientists, physicians, funders, and policy makers from over 70 institutions from over 30 countries have launched an international coalition to respond to COVID-19 in resource-poor settings. The COVID-19 Clinical Research Coalition aims to accelerate desperately needed COVID-19 research in those areas where the virus could wreak havoc on already-fragile health systems and cause the greatest health impact on vulnerable populations.

In a Comment published today in The Lancet, the members of the coalition argue that international research collaboration and coordination is needed urgently to support African, Latin American, Eastern European, and certain Asian countries to respond effectively to the worsening pandemic and speed up research adapted to resource-limited settings.

The coalition brings together an unprecedented array of health experts, including public-sector research institutes, ministries of health, academia, not-for-profit research and development organizations, NGOs, international organisations, and funders all committed to finding COVID-19 solutions for resource-poor settings.

One important research response to COVID-19 has been launched already, the World Health Organization (WHO)-led SOLIDARITY trial, an unprecedented global effort. But the authors found that out of almost 600 COVID-19 clinical trials registered, very few trials are planned in resource-poor settings. The authors commit to sharing their technical expertise and clinical trial capability to accelerate COVID-19 research in these settings.

The scale of the challenge is clearly beyond the scope of any single organization. The coalition will facilitate a coordinated approach, so that all data from all regions can be collected in a similar fashion, pooled and shared in real-time. This will help countries and the WHO to make rapid evidence-based decisions on policies and practice.   

"We welcome the launch of this coalition, which takes advantage of existing multinational and multidisciplinary expertise in running clinical trials in resource poor settings, and will help the World Health Organization in its coordinating role in the global response to COVID-19," said Dr Soumya Swaminathan, Chief Scientist, World Health Organization. "Although the epicentre is today elsewhere, we must prepare now for the consequences of this pandemic in more resource-constrained settings or we stand to lose many more lives."

Members of the coalition call for specific commitments to ensure access, so that effective new treatments are made available as soon as possible in resource-poor settings and are affordable and readily accessible.

Key Takeaways:

We propose a new way to measure how forward-looking consumers are based on their buying behavior, conditioning on their inventories at home.

Our method applies to storable goods such as laundry detergent, disinfectant spray, disinfectant wipes, toilet papers, etc.

Our estimates suggest that a consumer's planning horizon is roughly about 8 weeks.

Consumer buying behavior heavily depends on their expectation about future prices.

Anticipating shortages and high prices in the near future, "panic buying" can be explained as an outcome of rational stockpiling behavior by forward-looking consumers.

CATONSVILLE, MD, April 2, 2020 - Consumer stockpiling and hoarding took center stage in recent months as the COVID-19 virus has spread around the world, and with it, panic buying on the part of millions. News broadcasts and social media feeds have been filled with examples of the worst aspects of human nature.

Two marketing researchers, who have been studying this phenomena in-depth long before the current pandemic, have completed research and produced a study that reveals that a consumer's decision on how much to buy in each shopping trip depends on their current inventory, and what they expect prices to look like in the near future.

The forthcoming research study in the INFORMS journal Marketing Science, is titled "Identification and Estimation of Forward-Looking Behavior: The Case of Consumer Stockpiling." It is authored by Andrew Ching of Johns Hopkins University and Matthew Osborne of the University of Toronto.

"In particular, because the study finds that the extent by which consumers discount the future suggests that they only plan weeks ahead," said Ching. "The research focused on how consumers respond to price promotions in storable goods markets like basic food supplies, toilet papers, hand sanitizer, laundry detergent, etc. We learned that by properly factoring in the consumer's 'cost' of storage, combined with the number of packages stored, it is possible to determine how far ahead they plan. Our framework allows retailers to better determine price promotion strategies for products."

"A key parameter that determines how far ahead consumers plan is the discount factor, which measures the strength of forward-looking behavior," said Osborne. "Looking at what is happening now in supermarkets, our research suggests that in order to 'calm' people, we need to find a way to change consumer expectation about future prices and product availability in the near future."

"It would be very helpful if large retail chains and online retailers were to restock as soon as possible, and to assure consumers that they will not materially change regular prices and promotion frequencies," added Ching. "Putting a temporary limit on how much of a particular item consumers can buy, helps ensure product availability for more shoppers. Given that most consumers join a retailer's loyalty program, it is even possible for big retailers to learn consumers' recent purchase histories, and put a temporary limit on how many units one could buy per week, etc."

"Such a policy will help to smooth the product availability for the near term and will bring consumer expectations about future prices and availability in line with the pre-crisis period," said Osborne. "Our model suggests that consumer buying behavior will then return to normal. In addition, online retail marketplaces (e.g., Ebay, Amazon) or Department of Justice can also be more aggressive in monitoring for 'price gouging.' This should also help consumers to adjust their expectations."

URBANA, Ill. - You know that feeling in your gut? We think of it as an innate intuition that sparks deep in the belly and helps guide our actions, if we let it. It's also a metaphor for what scientists call the "gut-brain axis," a biological reality in which the gut and its microbial inhabitants send signals to the brain, and vice versa.

It's not a surprise that the brain responds to signals in the gut, initiating motor functions involved with digestion. Directed by the brainstem, these types of basic biological actions are largely automatic. But what if the higher brain - the thinking, emotional centers - were influenced by signals in the gut, too? New University of Illinois research in rats shows the entire brain responds to the gut, specifically the small intestine, through neuronal connections.

To map the connections, researchers inserted neuron-loving viruses in the rats' small intestines and traced the viruses as they moved from neuron to neuron along the Vagus and spinal nerves and throughout the brain. The idea was virus movement mimicked the movement of normal signals through neurons from the gut to the brain and back.

"We saw a lot of connections in the brainstem and hindbrain regions. We knew these regions are involved in sensing and controlling the organs of the body, so there weren't any big surprises there. But things got more interesting as the viruses moved farther up into parts of the brain that are usually considered emotional centers or learning centers, cognitive places. They have all these multifaceted functions. So thinking about how information from the small intestine might be nudging those processes a little bit is really cool," says Coltan Parker, doctoral student in the Neuroscience Program at Illinois and lead author on a study published in Autonomic Neuroscience: Basic and Clinical.

The study represents the first complete map of neuronal connections between the small intestine - what Parker and his co-authors call an "underloved" part of the digestive system - and the entire brain. The involvement of cognitive and emotional centers hints at how the thinking brain sometimes overrides our feeling of being full, provides fodder to explore relationships between depression and digestive troubles, and more.

"Now we're actually finding the neuro-anatomy that might be involved in that 'feeling in your gut,'" says Megan Dailey, study co-author and program administrator in the College of Agricultural, Consumer and Environmental Sciences at Illinois.

In addition to showing just how extensive the connections are between the small intestine and the brain, the study uncovered a rarely documented feature of the neurons themselves.

Scientists have long assumed sensations from the gut, or anywhere in the body, traveled to the brain along one set of neurons (the sensory neurons), with instructions from the brain traveling back along a separate set of neurons (the motor neurons). But in their mapping study, Illinois researchers discovered some of the neurons - about half - were transmitting both sensory and motor signals.

They were capable of cross-talk within the same neuron.

"From the cortex to the brainstem, in pretty much every region we investigated, there was that 50% overlap of sensory-motor signals. It was throughout the brain, consistently," says study co-author Elizabeth Davis. Davis is a 2018 graduate of the Illinois Neuroscience Program and is currently studying as a postdoctoral scholar at the University of Southern California.

The same pattern - 50% of neurons having both sensory and motor signaling capabilities - had only been shown one other time, in a study mapping neuronal connections between fat tissue and the brain. The researchers point out new evidence of the same crosstalk pattern could suggest a general architecture of neuronal networks between the body and brain.

"This study shows that sensorimotor feedback loops are abundant across all levels of the brain. Up until now, it has really been unknown how information in the small intestine, about nutrients or anything else, can get up to the brain and affect cognitive-emotional processes, and then how those processes can come back down and affect the gut," Parker says. "With more research, we may finally begin to understand how hunger makes us 'hangry,' or how a stressful day becomes an irritable bowel."

Evolution is a tinkerer, not an engineer. "Evolution does not produce novelties from scratch. It works with what already exists," wrote Nobel laureate François Jacob in 1977, and biologists continue to find this to be true.

Case in point: A team of scientists led by researchers at UC Santa Barbara has discovered that multiple opsin proteins, known for decades to be required for vision, also function as taste receptors. The finding, which appears in Current Biology, represents a light-independent function for opsins, and raises questions about the purpose these proteins served in ancient organisms.

"This is the first example of a role of opsins in taste, or in any form of chemical sensation," said coauthor Craig Montell, a distinguished professor of molecular, cellular, and developmental biology.

Scientists in the late 1800s discovered the light-sensing role of rhodopsin -- which consists of an opsin bound to retinal, a form of vitamin A -- and it has since become the most studied sensory receptor. Until recently, researchers believed that the family of rhodopsin proteins was involved only in light reception. However, in 2011, Montell and his colleagues found that an opsin enables the fruit fly Drosophila melanogaster to detect small temperature changes within its comfortable range.

Animals have many types of sensory proteins that respond to stimuli from the environment. Some require a strong stimulus, such as scalding heat, to activate. Rhodopsins are able to respond to very subtle changes or very low levels of stimuli-- like those in very dim light conditions -- and then initiate a molecular cascade that amplifies the signal, ultimately activating a sensory response.

Researchers in Montell's lab used aristolochic acid -- a toxic, bitter compound found in some plants -- to study taste receptors in fruit flies. High concentrations of this bitter chemical activate the flies' taste neurons by directly opening a channel protein called TRPA1, which lets calcium and sodium into the cells. This leads to a bitter taste the animals avoid. However, the flies also avoid even highly diluted aristolochic acid, which isn't a strong enough signal to open the channels directly.

Montell and lead author Nicole Leung, who recently completed her predoctoral studies at UC Santa Barbara, suspected opsin molecules might be at work in detecting subtle chemical signals as well, via a signal amplification process.

They presented flies with a choice between sugar alone or sugar spiked with dilute aristolochic acid. Unsurprisingly, the flies rejected the sugar laced with the bitter chemical and ate the pure sugar.

The scientists then raised fruit flies with mutations that prevented them from synthesizing different opsin proteins. They found that flies with defects in any one of three types of opsins couldn't detect the small concentrations of acid, and ate nearly equal amounts of the sugar laced with the bitter compound as the pure sugar. However, the mutant animals were still sensitive to large amounts of the bitter compound, which they continued to avoid. According to Montell, the large amounts of the bitter chemical directly activated the TRPA1 channel, which was still present in the flies missing the opsins.

The team showed that aristolochic acid activated these opsins by binding to the same site that retinal normally does in rhodopsin. Much like rhodopsins turned on by very dim light, the chemically-activated opsins then initiated a molecular cascade that amplified the small signals. This enabled the flies to detect concentrations of the compound that would otherwise be insufficient to trigger a response in their sensory neurons.

"Rhodopsins were discovered back in the 1870s," Montell said, "so to discover that opsins have roles in taste after 150 years or so is pretty exciting."

Montell speculates that chemoreception may have been the original role of opsin proteins. Chemical reception, he said, is a more basic requirement for life than is light reception. Knowing what to eat and what dangerous chemicals to avoid serves a more ancient survival function than does the ability to detect light. Perhaps by chance, he ventured, a retinal became bound to an opsin and conferred light sensitivity to the opsin.

Following Montell's 2011 discovery that opsins function in temperature sensation, another group found that opsins play a role in hearing in flies. Now, with the demonstration that opsins are taste receptors as well, Montell suspects they may be involved in still additional senses.

"In every case, they provide a mechanism for sensing low levels of stimuli by initiating an amplification cascade," he said.

The new finding likely extends beyond the fruit flies the scientists studied. "The ramifications are that maybe opsins represent a new class of taste receptor in mammals, including humans," said Montell, a hypothesis the team is currently investigating.

A new study by researchers at the University of Hawai'i at Mānoa School of Ocean and Earth Science and Technology (SOEST) found that human-induced environmental stressors have a large effect on the genetic composition of coral reef populations in Hawai'i. They confirmed that there is an ongoing loss of sensitive genotypes in nearshore coral populations due to stressors resulting from poor land-use practices and coastal pollution. This reduced genetic diversity compromises reef resilience. 

The study identified closer genetic relationships between nearshore corals in Maunalua Bay, Oahu and those from sites on West Maui, than to corals from the same islands, but further offshore. This pattern can be described as isolation by environment in contrast to isolation by distance. This is an adaptive response by the corals to watershed discharges that contain sediment and pollutants from land.

"While the results were not surprising, they clearly demonstrate the critical need to control local sources of stress immediately while concurrently addressing the root causes of global climate change," said Robert Richmond, research professor and director of the Kewalo Marine Laboratory and co-author of the study. "Additionally, this innovative science shows the need to track biodiversity at multiple levels."

This research provides valuable information to coral reef managers in Hawai'i and around the world who are developing approaches and implementation plans to enhance coral reef resilience and recovery through reef restoration and stressor reduction.

"This study shows the value of applying molecular tools to ecological studies supporting coral reef management," stated Kaho Tisthammer, lead researcher on this paper.

While the loss of coral colonies and species is easy to see with the naked eye, molecular tools are needed to uncover the effects of stressors on the genetic diversity within coral reef populations.

In the final few minutes of a spacecraft landing it is moving at hypersonic speeds through many layers of atmosphere. Knowing the air density outside of the vehicle can have a substantial effect on its angle of descent and ability to hit a specific landing spot. But air density sensors that can withstand the harsh hypersonic conditions are uncommon. A student from The Netherlands, working with an aerospace engineer at the University of Illinois at Urbana-Champaign, developed an algorithm that can run onboard a vehicle, providing important real-time data to aid in steering the craft, particularly during the crucial entry, descent, and landing stage.

"The algorithm we created can run in-flight, onboard the vehicle and estimate what the atmosphere outside is like," said Hamza El-Kebir, an undergraduate at Delft University of Technology. "So this is a complete game changer, because now you can use prior knowledge about the vehicle's motion to estimate the air density, inform your decisions in flight, and make minor alterations in your course. This can provide more certainty that you're going to hit that spot, instead of dealing with really conservative guidance."

El-Kebir conducted the research with Melkior Ornik, assistant professor in the Dept. of Aerospace Engineering at U of I, during a semester abroad program and will begin graduate school at Illinois in the fall. He said his work is new because it uses data from sensors that weren't intended to provide air density data. "It extracts that density information from it by using really nifty algorithms that don't require any real knowledge of the aerodynamics or the atmosphere."

Ornik explained how the algorithm learns the air density. "The algorithm starts from almost nothing. It doesn't know anything about the air density. It gathers data from accelerometers and gyroscopes available on any vehicle to gather data, and combines it with prior knowledge about maximal rate of acceleration to obtain a time-varying estimate of air density. And it gets, in a sense, smarter over time. It changes its estimations onboard, based on the input data it receives."

El-Kebir and Ornik used data acquired from the entry, descent, and landing of the Phoenix lander--a Mars science probe--representing the last 220 seconds, the ballistic phase, until parachute deployment.

"There's no steering at the later portion of that stage, so it's really important to immediately know the air density in the rarified flow regime--from about 80 kilometers and up. When it enters that later portion, its flight path angle gets fixed and the vehicle just descends, and is barely affected by the direction of the wind," El-Kebir said.

What if the Phoenix had the algorithm?

"If you know the air density, you can estimate your angle of attack with respect to the wind. You could also predict what the density will be like in the future, so you can make decisions. There was no control on Phoenix during the ballistic stage. If it had the knowledge of air density, it would have had an edge. They could have leveraged the data and landed more accurately."

Ornik said there is often an assumption that there exists a fixed model that we know in advance and we figure out control methods that lead the vehicle to land. "That is often a strong assumption. It's often wrong because it's not just about air density. Due to the speed and the impact with air, hypersonic vehicles change shape slightly during the flight and that changes their dynamics during flight."

"So we don't have a unified model that describes the whole flight because the dynamics change gradually over time. We know the maximal rate of change, so with this algorithm, we can exploit that knowledge to create an estimate," Ornik said.

El-Kebir said there are other fields this knowledge can be applied to, even outside of aerospace and even vehicles. He is looking at ways to use it in electrosurgery to predict the temperature field during a surgical operation so that the surgeon can know how deep the cut is.