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Berlin, 3 May - In a new report, ALLEA, the European Federation of Academies of Sciences and Humanities, examines the potential of technical and policy measures to tackle science disinformation and calls for improved European exchange and coordination in this field.

While disinformation strategies are intoxicating public discourses in many fields, science disinformation is particularly dangerous to democratic governance and society at large. As highlighted by the ongoing pandemic, an undermining of trust in science poses a fundamental threat to political and individual decisions based on evidence and scientific knowledge.

Over the past years, extensive research and a variety of strategies have been developed and applied to tackle science disinformation. ALLEA's paper reviews this work, focusing on the roots and consequences of this multi-dimensional phenomenon, as well as practical solutions for policy, technology and communication.

"The science race against Covid-19 has not only been in the search for a vaccine. Another major risk has mobilised researchers: science disinformation. This report identifies key pathways to counter this 'infodemic' in future global crises. Seeing these problems unfolding in our societies, we need an institutionalised and coordinated strategy to galvanise researchers, communicators, and policymakers into action as early as possible", says ALLEA President Antonio Loprieno.

The authors discuss the most prominent psychological, technical and political strategies to counter science disinformation, including inoculation, debunking, recommender systems, fact-checking, raising awareness, media literacy, as well as innovations in science communication and public engagement.

Following an analysis of the consequences of science disinformation in climate change, vaccine hesitancy and pandemics, the report concludes with a series of recommendations. The authors call for:

a stronger focus on communicating how science works and more dialogue in science communication practices,

a serious engagement with the public when exercising or communicating research,

valuing the virtue of intellectual humility when communicating scientific evidence,

the maintenance of good research practices and high ethical standards to ensure integrity and trustworthiness,

accountable, honest, transparent, tailored and effective science advice mechanisms.

To implement these proposals, the authors advise to establish a European Centre/Network for Science Communication and a European Code of Conduct for Science Communication.

"Even though there seems to be widespread awareness of the problems and harm caused by disinformation, there is still no coordinated European effort to respond to this with increased and better science communication. While mechanisms of science advice for policy have been introduced on different levels to bridge the gap between scientists and policymakers, no central pan-European mechanism or institution is in place to coordinate existing initiatives and develop coherent guidelines and recommendations on science communication in an inclusive manner", the authors argue.

The discussion paper will be presented and debated at the upcoming scientific symposium 'Across Boundaries in Sciences', held online on 5 May, during the 2021 ALLEA General Assembly. Registration is still open at: https://alleageneralassembly.org/

Globally, tuberculosis is the most common bacterial infectious disease leading to death. The pathogen causing tuberculosis, Mycobacterium tuberculosis, has a number of peculiarities. One is that it is growing very slowly. While other typical pathogens, such as pneumococcal and pseudomonads, can already be identified by their growth in the microbiological laboratory in the first 72 hours, several weeks usually pass before tuberculosis bacteria grow in the lab. Thus it often takes one to two months before the efficacy of individual medicines can be tested.

However, these efficacy tests are essential for the effective treatment of multidrug-resistant tuberculosis (MDR-TB), which is becoming increasingly common. In these cases, the pathogen has become resistant, i.e. insensitive, to the best tuberculosis drugs, rifampicin and isoniazid. This is due to changes in the genome, so-called mutations, which almost always occur at the same points in the genome. Treatment of MDR-TB is protracted, costly and frequently associated with side effects.

For the selection of antibiotics in a combination therapy, doctors have so far depended on the results of the drug test after cultivation. "Currently, 15 drugs are available for second-line therapy, of which at least four are used in combination," explains Prof. Christoph Lange, coordinator of the clinical study at the Research Center Borstel.

In order to accelerate the choice of the most effective antibiotics, DZIF scientists at the Research Center Borstel, led by Prof. Stefan Niemann, have created a catalogue of mutations in the genetic material of tuberculosis bacteria that permits prediction of antibiotic resistances of the bacteria against all drugs. Unlike many other bacteria, the genetic material of the tuberculosis bacteria hardly changes over time. The genome of tuberculosis bacteria carries roughly 4.4 millions of building blocks (base pairs) that store the information for about 4,000 genes.

Hans-Peter Grobbel, medical student and predoctoral DZIF fellow in Christoph Lange's team, supported by his fellow student Niklas Köhler, Professor Matthias Merker, Dr Sönke Andres and Dr Harald Hoffmans, has examined the results of antibiotic resistance predictions through overall genome analyses. Using tuberculosis bacteria from70 patients with MDR-TB treated at the Borstel Department of Medicine, researchers compared the molecular prediction of antibiotic resistance with actual cultural test results. They were contributed by Prof. Florian Maurer, Head of the National Reference Laboratory for Tuberculosis Bacteria in Borstel. The scientists also examined whether reliable combinations of drugs for the treatment of MDR-TB could be compiled based on the prediction of the bacteria´s genetic material.

"Ninety-nine per cent of all drugs in combination therapies that we have assembled based on the results of molecular predictions from the genetic material of tuberculosis bacteria are also effective according to traditional microbiological antibiotic resistance testing," Grobbel explains. By now, the molecular methods are both cheap and fast. Ideally, patients can already receive tailored MDR-TB treatment in the first week of their tuberculosis diagnosis.

If not before, then certainly since the first messenger RNA (mRNA) vaccines to combat the SARS CoV2 virus were approved in Germany, mRNA has become a recognized term even outside scientific circles. What is less well known is that mRNA can be used to produce much more than just vaccines. Around 50 different procedures for the treatment of diseases including cancer are already being studied in clinical trials. Scientists from the pharmaceutical company AstraZeneca, with the support of neutron researchers from Forschungszentrum Jülich, have now discovered how the subcutaneous administration of mRNA can be improved. The goal is for chronically ill patients to be able to self-administer the medication on a regular basis.

mRNA serves as a blueprint in our cells for the production of protein molecules. mRNA drugs could therefore create proteins directly in the patient's body, targeted at the site where they are needed. Besides cancer, many other diseases are potentially treatable: haemophilia, for example, where the formation of a clotting factor is disrupted, can be treated by administering the blueprint for this very factor. After heart attacks or strokes, injecting mRNA could enable the formation of proteins that allow new blood vessels to grow.

Compared to current therapeutics, producing mRNA is faster and more flexible, as mRNA can be easily manufactured and the process is independent of the mRNA sequence. In addition, the technology enables personalized drugs to be developed quickly and proteins can be produced in the body over an extended period of time and with modifications otherwise difficult to achieve.

mRNA is rapidly degraded in the body by ubiquitous enzymes. It is important to prevent this from happening before the mRNA reaches the cells where the protein synthesis takes place. In addition, it must be ensured that the messenger reaches the right cells and in sufficient quantities. Even though there are procedures in which the "naked" mRNA is administered, using secure packaging and some kind of "address label" is far more efficient.

An advanced packaging system is exemplified in so-called lipid nanoparticles (LNP), tiny vesicles made of a mixture of fat-like substances. Each of them fulfils a specific task, such as stabilising the construct or delivering it into the cell.

When administered intravenously or intramuscularly, the LNPs already fulfil their objectives sufficiently, but when administered subcutaneously, the LNP trigger significant inflammation. Subcutaneous application would be essential to enable patients to inject themselves with the drug, just as diabetes patients do with insulin. Particularly in chronic diseases that require regular doses of a drug, this would offer a great advantage.

So far, only small, insufficient quantities can be safely injected subcutaneously. Current studies from researchers at AstraZeneca and the Jülich Centre for Neutron Science (JCNS) show how this problem can be solved. The scientists supplemented the mRNA packaging with precursors of anti-inflammatory substances from the class of steroids. The body's own enzymes can convert these precursors into effective steroids at the site of injection.

Steroids have a strong anti-inflammatory effect, but can however have considerable side effects, especially if taken regularly. These side effects can be minimised by incorporating a steroid-precursor within the LNP so it is delivered and activated only at the site where it is needed i.e. the site where the LNPs are injected.

However, it is important to ensure that the steroid precursors are accessible to the enzymes. Therefore, they must be localised in the exterior of the lipid nanoparticles.

The researchers tried to ensure this by adding shorter or longer "fat-loving" extensions to the active substances. The idea is that the fat-loving areas would be inserted between the fatty substances of the LNP envelope in such a way that the steroid precursors would end up positioned on the outside. The scientists were able to prove that this is indeed the case with the help of neutron scattering studies at the small-angle scattering instrument KWS-2, operated by the JCNS at its outstation in the Heinz Maier-Leibnitz Zentrum in Garching.

"The KWS-2 instrument allows us to study fine structures, right down to nanostructures, using the contrast variation method," explains JCNS instrument scientist Dr. Aurel Radulescu. "In this process, the hydrogen atoms of individual components are exchanged for heavy hydrogen. This does not change the physical chemistry of the sample, but it does change the visibility for the neutrons. The neutrons can differentiate between the two isotopes and thus recognise which hydrogen atoms belong to which molecule." In this way, the different components of the lipid nanoparticles can be selectively labelled and differentiated from each other. And sure enough, the researchers found the steroid precursors on the outside of the particles, at least in the longer extensions.

"Understanding what the LNP surface looks like is fundamental to other challenges affecting LNP development," adds Dr. Marianna Yanez Arteta, Associate Principal Scientist in Advanced Drug Delivery at AstraZeneca. "Neutron scattering combined with selective isotope contrast is, to my knowledge, the only available technique that allows us to probe the lipid distribution and resolve the surface."

Further studies in AstraZeneca's laboratory confirmed the anti-inflammatory effect of the new LNP variants. The scientists also studied what length the fat-loving stem should be to ensure an optimal balance between efficient mRNA delivery and inflammatory response. "Incorporating an anti-inflammatory component into LNP greatly simplifies the therapy and may open it up to other treatments," predicts Dr. Yanez Arteta. If the anti-inflammatory LNPs now also prove their worth when used in humans, they could indeed unlock new therapeutic options for a wide range of diseases.

Scientists from the National Centre for radio Astrophysics of the Tata Institute of Fundamental Research (NCRA-TIFR) Pune used the upgraded Giant Metrewave Radio Telescope (uGMRT) to determine that AT 2018 cow, the first of a newly discovered class of cosmic explosions, has an extremely patchy environment. Sources like AT 2018cow release an enormous amount of energy, nonetheless fade extremely rapidly. This along with their extremely blue color has led to them being called FBOTs for Fast Blue Optical Transient. This is the first observational evidence of inhomogeneous emission from an FBOT. The origins of FBOTs are still under debate, but proposed models include explosion of a massive star, collision of an accreting neutron star and a star, merger of two white dwarfs, etc.

The FBOTs are difficult to find since they appear and vanish in the sky very quickly. However, several of them have been discovered in the past few years via the recent advent of surveys that scan the sky almost on daily basis. FBOTs that also emit in the radio are doubly rare, but are particularly interesting because radio observations help one to determine the properties of the environments of these explosions and their progenitors.

The FBOT AT 2018cow was discovered on 16 June 2018. At a distance of about 215 million light-years, the "cow" showed luminosities much greater than that of normal supernovae. Prof. Poonam Chandra (NCRA-TIFR) and Dr. A. J. Nayana (a former Ph.D. student of Prof. Poonam Chandra) carried out radio observations of AT 2018cow with the uGMRT to determine the properties of its extended environment and emission region. "Our study has tremendously benefited by the unique low-frequency capabilities of the uGMRT. The uGMRT observations of the "cow" played an unique role in finding the non-uniform density around this explosion", says Nayana. She added, "Our work provides the first observational evidence of inhomogeneous emission from an FBOT. The density of the material around this explosion falls drastically around 0.1 light-year from the transient. This indicates that the progenitor star of AT 2018cow was shedding mass much faster towards its end of life."

AT 2018cow is also unusual in that it has been observable in the radio for a very long time. The longer one can observe the post explosion emission, the more distance the material that was ejected during the explosion has traveled. This allows one to study the large scale environment of the source. Dr. A. J. Nayana and Prof. Poonam Chandra have been observing the "cow" for ~ 2 years with the uGMRT to understand its properties. "This is the first FBOT seen for this long at low radio frequencies and the uGMRT data gave crucial information about the environment of this transient.", Nayana said. Poonam Chandra explains, "This is the beauty of low-frequency radio observations. One gets to trace the footprints of the progenitor system much before it exploded. It is interesting that the material from the explosion is moving with speed greater than 20% speed of light even after ~257 days post-explosion, without any deceleration".

While the origin of FBOTs is still under debate, detailed radio observations can give hints about various physical parameters of these events like the speed of the material that came out of this explosion, the magnetic field strength, the rate by which the progenitor system sheds its mass before the explosion, etc. The uGMRT observations of the "cow" suggest that the progenitor erupted its material ~100 times faster during the years close to its end-of-life compared to ~23 years before the explosion. Also, AT 2018cow showed inhomogeneities in the radio-emitting region whereas the other two radio bright FBOTs did not show these properties, making the "cow" unique in the group. "Observations of more FBOTs with the uGMRT will give information about their environments and progenitors to develop a comprehensive picture of the properties of these intriguing transients.", says Nayana.

The GMRT is an array of thirty 45-m antennas spread over 25 sq-km area in Khodad village, Narayangaon, India, built and operated by NCRA-TIFR, Pune. Currently it is one of the most sensitive low frequency radio telescope in the world.

The paper was published in the April 30, 2021 issue of The Astrophysical Journal Letters.

"Image" is everything in the $20 billion market for AR/VR glasses. Consumers are looking for glasses that are compact and easy to wear, delivering high-quality imagery with socially acceptable optics that don't look like "bug eyes."

University of Rochester researchers at the Institute of Optics have come up with a novel technology to deliver those attributes with maximum effect. In a paper in Science Advances, they describe imprinting freeform optics with a nanophotonic optical element called "a metasurface."

The metasurface is a veritable forest of tiny, silver, nanoscale structures on a thin metallic film that conforms, in this advance, to the freeform shape of the optics--realizing a new optical component the researchers call a metaform.

The metaform is able to defy the conventional laws of reflection, gathering the visible light rays entering an AR/VR eyepiece from all directions, and redirecting them directly into the human eye.

Nick Vamivakas, a professor of quantum optics and quantum physics, likened the nanoscale structures to small-scale radio antennas. "When we actuate the device and illuminate it with the right wavelength, all of these antennas start oscillating, radiating a new light that delivers the image we want downstream."

"Metasurfaces are also called 'flat optics' so writing metasurfaces on freeform optics is creating an entirely new type of optical component," says Jannick Rolland, the Brian J. Thompson Professor of Optical Engineering and director of the Center for Freeform Optics.

Adds Rolland, "This kind of optical component can be applied to any mirrors or lenses, so we are already finding applications in other types of components" such as sensors and mobile cameras.

WHY FREEFORM OPTICS WEREN'T ENOUGH

The first demonstration required many years to complete.

The goal is to direct the visible light entering the AR/VR glasses to the eye. The new device uses a freespace optical combiner to help do that. However, when the combiner is part of freeform optics that curve around the head to conform to an eyeglass format, not all of the light is directed to the eye. Freeform optics alone cannot solve this specific challenge.

That's why the researchers had to leverage a metasurface to build a new optical component.

"Integrating these two technologies, freeform and metasurfaces, understanding how both of them interact with light, and leveraging that to get a good image was a major challenge," says lead author Daniel Nikolov, an optical engineer in Rolland's research group.

THE CHALLENGE OF FABRICATION

Another obstacle was bridging "from macroscale to nanoscale," Rolland says. The actual focusing device measures about 2.5 millimeters across. But even that is 10,000 times larger than the smallest of the nanostructures imprinted on the freeform optic.

"From a design standpoint that meant changing the shape of the freeform lens and distributing the nanostructures on the lens in a way that the two of them work in synergy, so you get an optical device with a good optical performance," Nikolov says.

This required Aaron Bauer, an optical engineer in Rolland's group, to find a way to circumvent the inability to directly specify metasurfaces in optical design software. In fact, different software programs were used to achieve an integrated metaform device.

Fabrication was daunting, Nikolov says. It required using electron-beam lithography, in which beams of electrons were used to cut away sections of the thin-film metasurface where the silver nanostructures needed to be deposited. Writing with electron beams on curved freeform surfaces is atypical and required developing new fabrication processes.

The researchers used a JEOL electron-beam lithography (EBL) machine at the University of Michigan's Lurie Nanofabrication Facility. To write the metasurfaces on a curved freeform optic they first created a 3D map of the freeform surface using a laser-probe measuring system. The 3D map was then programmed into the JEOL machine to specify at what height each of the nanostructures needed to be fabricated.

"We were pushing the capabilities of the machine," Nikolov says. Fei Cheng, a postdoctoral associate in the Vamivakas group; Hitoshi Kato, a JEOL representative from Japan, and the Michigan staff of the nanofabrication lab, collaborated with Nikolov on achieving successful fabrication "after multiple iterations of the process."

"This is a dream come true," Rolland says. "This required integrated teamwork where every contribution was critical to the success of this project."

Tiny 3-D models that mimic vital aspects of the human nervous system have been developed in a step that could accelerate drug research for neurological conditions such as multiple sclerosis (MS).

The millimetre-wide models - created using stem cells from human skin samples - will be used to study myelin, an insulating substance that helps nerve cells communicate with each other.

Researchers say the models are the most natural representation of human myelination developed in a lab and are a promising platform for studying neurological diseases and for testing drugs for conditions linked to myelin loss, including MS.

Nerve cells are found in the brain and the spinal cord and connect to each other with branch-like links called axons, which have an insulating coat similar to electric cabling. This insulating coat is called myelin, and it aids the electrical and chemical information flow between cells.

Damaged myelin underlies a number of neurological conditions including MS - an incurable disease affecting more than 100,000 people in the UK - and leads to a wide range of symptoms, including mobility issues, fatigue and vision problems.

Scientists at the University of Edinburgh's Anne Rowling Regenerative Neurology Clinic and the Euan MacDonald Centre for Motor Neuron Disease Research developed their human myelin model using skin samples donated by volunteers.

Skin cells were reprogrammed into induced pluripotent stem cells, which can be turned into other cell types - in this case - spinal cord cells.

These cells were then grown slowly into organoids - 3-D structures of cell bundles including neurons and distinctive brain cells known as oligodendrocytes that are key to creating myelin.

Crucially, the researchers were able to see myelin developing spontaneously around the axons between cells within the organoids.

By looking at the axons under a microscope, they could see that the myelin in this model was functioning as it would in a healthy brain or spinal cord.

The research team then created an organoid using stem cells from a patient with a rare gene mutation that affects myelination. The model showed that key aspects of this cell bundle were consistent with the disease.

These new models will allow scientists to compare the differences between the cells of healthy individuals and those with different neurological diseases and to test drugs of interest in human cells before using them in a full clinical trial with patients.

The researchers hope that their model will overcome the challenges of studying the human brain and nervous system at the cellular level, which is extremely difficult due to problems accessing brain and spinal cord tissue without risk and huge inconvenience to patients.

The approach complements animal models, which can be limited in how they reflect human disease and the way that drugs interact with human cells.

The authors say the model is a significant step forward in the study of human myelination and drug development, but caution that treatments tested on this model are still some way from being offered to patients.

The study was funded by the Euan MacDonald Centre and is published in the journal Developmental Cell with DOI: 10.1016/j.devcel.2021.04.006. The research was carried out in collaboration with the UK Dementia Research Institute and the MS Society Centre for MS Research at the University of Edinburgh.

Lead researcher, Dr Owen Gwydion James, said: "Demyelinating disorders have a profound effect on the quality of life for patients. Now we have the capability of studying human myelination experimentally, a major goal is to identify drugs that can promote myelination. We believe that this new approach could be a huge boost to the toolbox that allows us to do this effectively."

An extraordinary discovery in the Gulf of Eilat: Researchers from Tel Aviv University have discovered a species of ascidian, a marine animal commonly found in the Gulf of Eilat, capable of regenerating all of its organs - even if it is dissected into three fragments. The study was led by Prof. Noa Shenkar, Prof. Dorothee Huchon-Pupko, and Tal Gordon of Tel Aviv University's School of Zoology at the George S. Wise Faculty of Life Sciences and the Steinhardt Museum of Natural History. The findings of this surprising discovery were published in the leading journal Frontiers in Cell and Developmental Biology.

"It is an astounding discovery, as this is an animal that belongs to the Phylum Chordata - animals with a dorsal cord - which also includes us humans," explains Prof. Noa Shenkar. "The ability to regenerate organs is common in the animal kingdom, and even among chordates you can find animals that regenerate organs, like the gecko who is able to grow a new tail. But not entire body systems. Here we found a chordate that can regenerate all of its organs even if it is separated into three pieces, with each piece knowing exactly how to regain functioning of all its missing body systems within a short period of time."

There are hundreds of species of ascidians, and they are found in all of the world's oceans and seas. Anyone who has ever opened their eyes underwater has seen ascidians without knowing it, as they often camouflage themselves as lumps on rocks and are therefore difficult to discern. The animal that is the subject of this new study is an ascidian from the species Polycarpa mytiligera, which is very common in the coral reefs of Eilat.

"By all accounts, the ascidian is a simple organism, with two openings in its body: an entry and an exit," says Tal Gordon, whose doctoral dissertation included this new research. "Inside the body there is a central organ that resembles a pasta strainer. The ascidian sucks in water through the body's entry point, the strainer filters the food particles that remain in the body, and the clean water exits through the exit point. Among invertebrates, they are considered to be the closest to humans from an evolutionary point of view."

Ascidians are famous for their regenerative ability, but until now these abilities have been identified mainly in asexual reproduction. Never before has such a high regenerative capacity been detected in a chordate animal that reproduces only by sexual reproduction.

"There are species of ascidians that perform simple regeneration in order to reproduce," Gordon says. "These are species with a colonial lifestyle, with many identical individuals connected to one another. They replicate themselves in order to grow. In contrast, the ascidian from Eilat, Polycarpa mytiligera, is an organism with a solitary lifestyle, without the capacity for asexual reproduction, similar to humans. In previous studies we showed that this species is able to regenerate its digestive system and its points of entrance and exit within a few days. But then we wanted to see if it is capable of renewing all of its body systems. We took a few individual ascidians from Eilat and dissected them into two parts, which were able to replenish the removed sections without any problem. In a subsequent experiment, we dissected several dozen ascidians into three fragments, leaving a part of the body without a nerve center, heart, and part of the digestive system. And contrary to our expectations, not only did each part survive the dissection on its own, all of the organs were regenerated in each of the three sections. Instead of one ascidian, there were now three. This is very astonishing. Never before has such regenerative capacity been discovered among a solitary species that reproduces sexually, anywhere in the world."

Prof. Shenkar concludes: "Since the dawn of humanity, humans have been fascinated by the ability to regenerate damaged or missing organs. Regeneration is a wonderful ability that we have, to a very limited extent, and we would like to understand how it works in order to try and apply it within our own bodies. Anyone snorkeling in the Gulf of Eilat can find this intriguing ascidian, who may be able to help us comprehend processes of tissue renewal that can help the human race."

The human world is, increasingly, an urban one -- and that means elevators. Hong Kong, the hometown of physicist Zhijie Feng (Boston University),* adds new elevators at the rate of roughly 1500 every year...making vertical transport an alluring topic for quantitative research.

"Just in the main building of my undergraduate university, Hong Kong University of Science and Technology," Feng reflects, "there are 37 elevators, all numbered so we can use them to indicate the location of hundreds of classrooms. There is always a line outside each elevator lobby, and if they are shut down, we have to hike for 30 minutes."

Feng and Santa Fe Institute Professor Sidney Redner saw this as an opportunity to explore the factors that determine elevator transport capabilities. In their new paper in the Journal of Statistical Mechanics, they begin by making a deliberately simple "toy" model.

"Engineers have already developed computational models for simulating elevators as realistically as possible," says Feng. "Instead, we wanted insight into basic mechanisms, using just enough parameters to describe what we see in a way we can fully understand."

Their minimum-variable simulation makes six key assumptions: unoccupied buildings, first-come-first-served transport, identical elevators traveling to uniformly distributed destination floors, 2.5 seconds to enter or exit elevators, and one second to travel from one floor to the next.

For a 100-story building with one idealized infinite-capacity elevator, Feng and Redner find that waiting times typically fall between five and seven minutes. With elevators that can carry 20 people each, and buildings that hold 100 workers per floor, this cycle requires 500 trips over 2 hours -- or 21 elevators -- to get everyone to work on time.

"If the elevators are uncorrelated," the authors write, wait time "should equal the single elevator cycle time divided by the number of elevators, which is roughly 15 seconds." However, this efficient spacing of elevators doesn't last: as passenger demand increases, elevators start to move in lockstep, creating traffic jams in the lobby below until multiple elevators arrive back on the ground floor at the same time.

These nonlinear dynamics stymie any easy answer to the question of how long a person has to wait. But to Feng and Redner this is just the entry-level to a bigger inquiry. "I hope our work could be a 'pocket version' model to extend from," Feng remarks. She credits Redner's textbook, which she read in her early undergraduate days, for inspiring her love of breaking down complex problems into simple models.

Some of the further questions they identify include, "If a building tapers with height, is there a taper angle that minimizes waiting time but optimizes office space?"; and, "What if some elevators only service certain floors, and others service different floors?"

Food for thought next time you're waiting in the lobby...

Nearly 10,000 acres of lush seagrass vanished from Florida Bay between 1987 and 1991, leading to massive ecological changes in the region near the Florida Keys. Abundance of the seagrass, Thalassia testudinum, more commonly known as turtlegrass, a foundation species of the Florida Bay ecosystem, decreased extensively during what is considered to be one of the largest declines in seagrass cover in recent history.

Researchers from the University of South Florida, the Florida Fish and Wildlife Conservation Commission (FWC) and the University of North Carolina Wilmington documented the response of seagrasses after the die-off. Their detailed data collection for over 20 years across the large area of impact has provided unique insight into seagrass resiliency or the ability of a coastal ecosystem to recover after the extensive loss. This study, published in "Scientific Reports," is extremely timely as the work provides a framework for how future recovery of a new seagrass die-off, recorded in 2015 in the same location, may still be possible.

Seagrass plays an important role across much of the Gulf of Mexico and Caribbean Sea, providing critical habitat and feeding grounds for many species of fish, turtles and other wildlife. They're considered to be one of the most productive ecosystems in the world and in Florida Bay contribute to a sport fishing industry worth hundreds of millions of dollars per year.

USF Distinguished University Professor Susan Bell first learned of the 1987 large-scale seagrass die-off in Florida when she got a call from a long-time fisherman friend who noticed the seagrass disappearing and large amounts of dead seagrass. Bell notified colleagues at FWC, who began to detail what was happening across a roughly 15 square mile stretch of the bay.

For more than 10 years, researchers saw little to no change in seagrass, especially in the levels of turtlegrass. However, after another decade of monitoring, researchers reported a return to pre-die-off levels of turtlegrass in the region. The study shows that the entire sequence of die-off, algal blooms and recovery took 17-23 years. Both the long duration of the study and large area over which the data were systematically collected were unique to reports of seagrass recovery. Also, most studies of marine populations that recover from some kind of disturbance are linked to human intervention, such as removing a source of pollution, but in this case the recovery required no human activities.

"While the fact this system recovered after the 1980s die-off is fantastic, we really wanted to figure out the mechanisms that allowed recovery to happen," said Bell, a faculty member in the USF Department of Integrative Biology. "What we discuss are a number of features that underlie the seagrass recovery: the system was remote, remnants of seagrass leftover after the die-off served as a catalyst for repopulation and having multiple species of seagrass present increases the likelihood for recovery."

In the last case, two opportunistic seagrass species were first to increase in abundance after the die-off and likely facilitated the return of turtlegrass.

Bell believes this study can serve as a framework for other regions experiencing seagrass die-off, including once again in Florida Bay, which is still in the midst of the die-off that began in 2015. Their work warns that evaluation of ecosystem resiliency may take decades to detect, mandating long-term studies. Researchers are continuing to study the changes in Florida Bay, but are hopeful that with the right conditions, the region can once again return to normal.

"Today, this monitoring program provides some of our best information on the status of the system," said Brad Furman, a co-author of the study and research scientist at FWC's Fish and Wildlife Research Institute. "Studies like this one allow us to set expectations for recovery, something we did not have in the 1990s, which is extremely important as we watch the Bay respond to the most recent die-off event."

New Haven, Conn. --Yale researchers have shown that developmental abnormalities, including those that lead to pregnancy loss and autism, are controlled by the genetics of the fetus and placenta -- and not the mother's intrauterine environment.

The findings are reported in the April 28 online edition of the journal Placenta.

One out of every 33 children is diagnosed with a birth defect each year in the United States, according to the Centers for Disease Control and Prevention (CDC). This translates into one baby born every 4 ½ minutes -- or 120,000 per year.

"Mothers often feel that they are responsible for these defects. But it's not their fault," said senior author Dr. Harvey Kliman, a research scientist in the Department of Obstetrics, Gynecology & Reproductive Services at the Yale School of Medicine. "This new research points to the genetics of these children as being the most important cause."

For the study, Kliman's team examined placental data for nearly 50 sets of identical and non-identical twins. The researchers found that abnormal cell growths called trophoblast inclusions (TIs) which are markers for many developmental abnormalities, occurred with similar frequency in identical twins, while non-identical twins showed a markedly different TI count.

Identical twins share the same DNA sequence; non-identical twins share half of their DNA sequence. The researchers found that identical twins often had the same number of TIs or were within one of having the same TI count. Non-identical twins had TI counts that were, on average, different by four or five.

"This work suggests that developmental abnormalities are much more likely to be due to the genetics of the child, and not the mother's fault," Kliman said.

Lead author Julia Katz, a former Yale undergraduate who is now a medical student at Hofstra University, provided the inspiration for the study.

Katz and her brother, Jesse, who was born underweight and with several congenital abnormalities, are non-identical twins. "I had a lot of guilt, growing up, about why my twin had certain conditions that I didn't," Katz said. "I think mothers also tend to blame themselves."

Katz approached Kliman after a Yale lecture and asked him what causes babies to be born undersized. The conversation led to a discussion about developmental abnormalities and Katz's desire to seek out information about her and her twin's genetics -- including looking at her own placental slides from birth.

It also led Kliman, Katz, and co-author Parker Holzer, a graduate student in the Yale Department of Statistics and Data Science, to conduct the new study.

"Julia's need to resolve this burden is what propelled our study," Kliman said. "Hopefully, this finding will help many other people, as well."

Katz added: "This experience has shown me that if you have a question, ask it. And if you don't get an answer, try to answer it yourself."

CHAPEL HILL, North Carolina--A comprehensive review by University of North Carolina researchers and colleagues highlights the optimal ways that focused, high-dose radiation can be delivered to various types of tumors while sparing normal tissue and mitigating long-term side effects. The review was reported as a special issue in the International Journal of Radiation Oncology, Biology, Physics on May 1, 2021.

This analysis was based on an exhaustive review of data and the literature published largely in the past decade. It updates an earlier review that primarily focused on the effects of conventional radiation therapy on normal tissue. This new review also includes important analyses of how well high-dose radiation can destroy small tumors, such as small brain lesions, lung lesions, and cancers that metastasize to other parts of the body.

"We undertook this review because we have an ever-increasing knowledge about the dose and volume of tissue to which we can direct radiation to both eradicate tumors while also safeguarding the surrounding normal tissue," said Lawrence B. Marks, MD, chair of the UNC Department of Radiation Oncology and Dr. Sidney K. Simon Distinguished Professor of Oncology Research at UNC Lineberger Comprehensive Cancer Center. "Today, we are better able to tailor radiotherapy to optimize benefit and minimize risk."

Conventional radiotherapy, developed nearly a century ago, often broadly hits the tumor and some healthy tissue surrounding the tumor, and is administered in low daily doses, usually over many weeks. For some patients, their cancer can be treated with more advanced techniques, called stereotactic body radiation therapy, or radiosurgery, that target smaller areas of tissue that are primarily cancerous, treating them at a high dose per day and usually administered for one to five days. These radiosurgery treatments are the focus of this recently published report.

Marks said UNC is a leader in radiosurgery treatments. "We are lucky to have specialized equipment and expertise to deliver these types of treatments." He added that UNC's multidisciplinary approach to cancer care brings together clinical collaborators to work in partnership with radiosurgery program to care for a wide range of cancers, including brain, thoracic, gastrointestinal and genitourinary cancers.

"New computational methods and machines allow us to deliver radiotherapy much more accurately today, allowing us to limit the area where the radiation is targeted, thereby giving us the ability to increase the dose per day," Marks said. "However, at this point in time we can only use this approach for smallish-sized tumors, but newer techniques may allow us to extend this approach to larger tumors as well."

Because it takes years for data to accrue and mature, the next review will be done when there are discernable shifts or changes in treatment practice patterns, according to the authors. However, there is a large review due out next year, in which Marks is participating, that is focusing on use of radiotherapy in pediatric cancers. Radiotherapy is often used sparingly in children due to later-in-life side effects, therefore making it important to know when best to use these treatments.

"Radiation therapy is now safer than ever. Our analysis will help support the growing use of the latest forms of radiotherapy, which are proving to be a very effective in treating many primary and metastatic lesions," Marks concluded.

The Bornean subspecies of Rajah scops owl (Otus brookii brookii), documented in the wild for the first time since 1892, may be its own unique species and deserving of a conservation designation. Published April 28 in The Wilson Journal of Ornithology, Smithsonian Migratory Bird Center ecologist Andy Boyce reported the rediscovery and photographed this elusive subspecies in the mountainous forests of Mount Kinabalu in Sabah, Malaysia.

"It was a pretty rapid progression of emotions when I first saw the owl--absolute shock and excitement that we'd found this mythical bird, then pure anxiety that I had to document it as fast as I could," Boyce said. "Based on size, eye color and habitat, I knew it was the Bornean Rajah scops owl. What's more, taking into account this bird's specific plumage characters, known speciation patterns within the Otus genus and phylogeographic patterns of montane birds in Borneo and Sumatra, O. b. brookii is likely its own unique species and further study is needed."

Scops owls weigh approximately 100 grams (about 4 ounces), equivalent to four AA batteries. Both subspecies of Rajah scops owl are native to southeast Asia--Otus brookii brookii on the island of Borneo and Otus brookii solokensis on Sumatra. Small owls in the genus Otus often show rapid divergence following isolation in this region. In fact, the Indonesian archipelago is composed of islands that facilitate species divergence, and Borneo and Sumatra have been particularly prone to speciation events.

The serendipitous discovery occurred in May 2016 as part of a 10-year study of avian life-history evolution at Mount Kinabalu in seven study plots at elevations from 1,500-1,900 meters (about 5,000-6,200 feet). The project was led by T.E. Martin, assistant unit leader and research wildlife biologist with the Montana Cooperative Wildlife Research Unit at the University of Montana. While nest-searching in May 2016, technician Keegan Tranquillo notified Boyce, then a doctoral student at the University of Montana, after spotting a roosting scops owl larger and with different plumage than the regularly encountered Mountain scops owl (O. spilocephalus luciae).

"Unfortunately, we are only good at conserving what we know and what we name," Boyce said. "If this rare bird is endemic only to Borneo and is its own species, conservation action is more likely. Our sole sighting during this intensive study confirms this owl lives in mature montane forests, likely above or below the survey area. Those elevations are already threatened by habitat loss due to climate change, deforestation and palm oil development. To protect this bird, we need a firm understanding of its habitat and ecology."

Almost all data on this species is of the Sumatran subspecies. O. b. brookii's vocalizations, distribution, breeding biology and population size are totally unknown. Despite the lack of information on the species and subspecies, and the apparent rarity of the Bornean taxa, the Rajah scops owl was designated a species of least concern by the International Union for Conservation of Nature.

Properly resolving the ecology, distribution and taxonomic standing of O. b. brookii could have important conservation implications toward both subspecies of owls given each would be an island-endemic species. Researchers recommend nocturnal surveys in specific elevations to study habitat, record vocalizations and collect blood or feather samples to resolve the taxonomic relationship between O. brookii subspecies.

MADISON -- From radio to television to the internet, telecommunications transmissions are simply information carried on light waves and converted to electrical signals.

Silicon-based fiber optics are currently the best structures for high-speed, long distance transmissions, but graphene -- an all-carbon, ultra-thin and adaptable material -- could improve performance even more.

In a study published April 16 in ACS Photonics, University of Wisconsin-Madison researchers fabricated graphene into the smallest ribbon structures to date using a method that makes scaling-up simple. In tests with these tiny ribbons, the scientists discovered they were closing in on the properties they needed to move graphene toward usefulness in telecommunications equipment.

"Previous research suggested that to be viable for telecommunication technologies, graphene would need to be structured prohibitively small over large areas, (which is) a fabrication nightmare," says Joel Siegel, a UW-Madison graduate student in physics professor Victor Brar's group and co-lead author of the study. "In our study, we created a scalable fabrication technique to make the smallest graphene ribbon structures yet and found that with modest further reductions in ribbon width, we can start getting to telecommunications range."

Graphene is hailed as a wonder-material for technologies like telecommunications or solar cells because it is easy to work with, is relatively inexpensive, and has unique physical properties such as being both an insulator and conductor of electricity.

If modified to interact with higher energy light, graphene could be used to modulate telecommunications signals at lightning-quick speeds. For example, it could be used to block unwanted communications frequencies.

One way to improve graphene's performance is to cut it into microscopic, nanometer-scale ribbon structures, which act as tiny antennas that interact with light. The smaller the antenna, the higher energies of light it interacts with. It can also be "tuned" to interact with multiple light energies when an electric field is applied, stretching its performance further.

The researchers, including teams led by UW-Madison materials science and engineering professors Michael Arnold and Padma Gopalan, first wanted to make a device of graphene ribbons that were narrower than anything made yet. By constructing ribbon-shaped polymers on top of graphene and then etching away some of the surrounding material, they were left with precisely drawn, impossibly thin ribbons of graphene.

"It's very useful because there are not good fabrication techniques to get down to the feature size we did, 12 nanometers wide over a large area," Siegel says. "And there is no difference between patterning over the centimeter-scale we're working with here and giant six-inch wafers useful for industrial applications. It's very easy to scale up."

With the devices fabricated, the researchers could then test how the ribbons interacted with light and how well they could control that interaction.

In conjunction with UW-Madison electrical and computer engineering professor Mikhail Kats' group, they shined different¬ wavelengths of infrared light into the structures and identified the wavelength where the ribbons and light interacted the most strongly, known as the resonant wavelength.

They found that as ribbon width decreases, so does the resonant wavelength of light. Lower wavelengths mean higher energies, and their devices interacted with the highest energies measured yet for structured graphene.

The researchers were also able to tune the ribbons by increasing the electric field strength applied to the structures, further reducing the structures' resonant wavelength. The researchers determined that one structure has the expected flexibility needed for the technology applications they were aiming to achieve.

They then compared their experimental data to the predicted behaviors of structured graphene across three different ribbon widths and three electric field strengths. The wider ribbons the researchers created closely matched the predicted behaviors.

But for narrower ribbons, they saw a so-called blueshift, or a shift to higher-than-expected energies. The blueshift can be explained by the fact that electrons in the smaller ribbons would be more likely to interact with -- and repel -- each other.

"The blueshift we observed indicates that telecommunications wavelengths can be reached with much larger structures than previously expected -- around eight-to-10 nanometers -- which is only marginally smaller than the 12 nanometers structures we made," Siegel says.

With the eight-to-10 nanometer goal much closer than expected, the researchers are now trying to tweak their fabrication methods to make the ribbons even narrower. These new graphene nanostructures will also allow explorations into the fundamental physics of light-matter interactions, research that Siegel and colleagues are currently pursuing.

When it comes to batteries, lithium-ion are the best we have as far as energy density and convenience.

For now.

The Washington University in St. Louis lab of Peng Bai, assistant professor in the Department of Energy, Environmental & Chemical Engineering in the McKelvey School of Engineering, has developed a stable sodium ion battery that is highly efficient, will be less expensive to make and is significantly smaller than a traditional lithium ion battery due to the elimination of a once-necessary feature.

"We've found that the minimal is maximum," Bai said. "No anode is the best anode."

The research was published May 3, 2021, in the journal Advanced Science.

A traditional lithium ion battery consists of a cathode and anode, both of which store lithium ions; a separator to keep the electrodes separated on either side; and an electrolyte -- the liquid through which the ions move. When lithium flows from the anode to the cathode, free electrons leave through the current collector to the device being powered while the lithium passes the separator to the cathode.

To charge, the process is reversed, and the lithium passes from the cathode, through the separator, to the anode.

The concept of replacing lithium with sodium and doing away with the anode isn't new.

"We used old chemistry," Bai said. "But the problem has been, with this well-known chemistry, no one ever showed this anode-free battery can have a reasonable lifetime. They always fail very quickly or have a very low capacity or require special processing of the current collector."

Anode-free batteries tend to be unstable, growing dendrites -- finger-like growths that can cause a battery to short or simply to degrade quickly. This conventionally has been attributed to the reactivity of the alkali metals involved, in this case, sodium.

In this newly designed battery, only a thin layer of copper foil was used on the anode side as the current collector, i.e., the battery has no active anode material. Instead of flowing to an anode where they sit until time to move back to the cathode, in the anode-free battery the ions are transformed into a metal. First, they plate themselves onto copper foil, then they dissolve away when it's time to return to the cathode.

"In our discovery, there are no dendrites, no finger-like structures," said Bingyuan Ma, the paper's first author and a doctoral student in Bai's lab. The deposit is smooth, with a metal luster. "This kind of growth mode has never been observed for this kind of alkali metal."

"Observing" is key. Bai has developed a unique, transparent capillary cell that offers a new way to look at batteries. Traditionally, when a battery fails, in order to determine what went wrong, a researcher can open it up and take a look. But that after-the-fact kind of observation has limited usefulness.

"All of the battery's instabilities accumulate during the working process," Bai said. "What really matters is instability during the dynamic process, and there's no method to characterize that." Watching Ma's anode-free capillary cell, "We could clearly see that if you don't have good quality control of your electrolyte, you'll see various instabilities," including the formation of dendrites, Bai said.

Essentially, it comes down to how much water is in the electrolyte.

Alkali metals react with water, so the research team brought the water content down. "We were hoping just to see a good performance," Bai said. Watching the battery in action, the researchers shortly saw shiny, smooth deposits of sodium. It's the smoothness of the material that eliminates morphological irregularities that can lead to the growth of dendrites.

"We went back to check the capillary cells and realized there was a longer drying process of the electrolyte," Bai said. Everyone talks about the water content in batteries, but, in previous research, the amount of water had often been relegated to simply a statistic that needed to be noted.

Bai and Ma realized that it was, in fact, the key.

"Water content must be lower than 10 parts-per-million," Bai said. With that realization, Ma was able to build not just a capillary cell, but a working battery that is similar in performance to a standard lithium-ion battery, but takes up much less space because of the lack of an anode.

"Check your cell phone. Your electric car. One quarter of the cost of such items comes from the battery," Bai said. Sodium batteries use a more common metal than lithium batteries; they have the same energy density as lithium batteries; and they are smaller and cheaper than lithium batteries, thanks to the elimination of the anode.

"We proved you can use the simplest setup to enable the best battery," Bai said.

Hydraulic fracturing to extract trapped fossil fuels can trigger earthquakes. Most are so small or far from homes and infrastructure that they may go unnoticed; others can rattle windows, sway light fixtures and jolt people from sleep; some have damaged buildings.

Stanford University geophysicists have simulated and mapped the risk of noticeable shaking and possible building damage from earthquakes caused by hydraulic fracturing at all potential fracking sites across the Eagle Ford shale formation in Texas, which has hosted some of the largest fracking-triggered earthquakes in the United States.

Published April 29 in Science, the results show the most densely populated areas - particularly a narrow section of the Eagle Ford nestled between San Antonio and Houston - face the greatest risk of experiencing shaking strong enough to damage buildings or be felt by people. "We found that risks from nuisance or damage varies greatly across space, depending mostly on population density," said lead study author Ryan Schultz, a PhD student in geophysics at Stanford.

Social license

Tens of thousands of wells drilled in the vast formation over the past decade helped to fuel the U.S. shale boom and contributed to a dramatic increase in earthquakes in the central and eastern U.S. starting around 2009. Although damaging earthquakes are rare, the authors write, "the perceived risks of hydraulic fracturing have both caused public concern and impeded industry development."

In sparsely populated areas within the southwestern portion of the Eagle Ford, the researchers found damage is unlikely even if fracking causes earthquakes as large as magnitude 5.0. Allowing such powerful quakes, however, could jeopardize the "social license to operate," they write. The phrase, which emerged within the mining industry in the 1990s and has since been adopted by climate activists, refers to the unofficial acceptance by local community members and broader civil society that oil, gas and mining operations need to do business without costly conflicts.

"Seismicity is part of the social license for hydraulic fracturing, but far from the only issue," said study co-author Bill Ellsworth, a geophysics research professor at Stanford's School of Earth, Energy & Environmental Sciences (Stanford Earth). "Eliminating hydraulic fracturing seismicity altogether wouldn't change any of the other concerns."

Among those concerns are health threats from living near oil and gas wells and greenhouse gas emissions from fossil fuel production and use. California's recent announcement of plans to stop issuing new permits for hydraulic fracturing by 2024, for example, comes as part of an effort to phase out oil extraction and reduce greenhouse gas emissions.

Starting with risk

The researchers say their goal is to make it easier for operators, regulators, local residents and property owners to discuss the risks that are important to them without technical expertise. "The approach we've developed provides the risk of nuisance or damage as a shared frame of reference and tools to evaluate it," said study co-author and geophysics professor Greg Beroza, co-director of the Stanford Center for Induced and Triggered Seismicity (SCITS).

The new risk analysis applies a technique first published last year for considering where people and structures are located as well as forecasts for maximum earthquake magnitude and geological factors that can amplify or dampen tremors as they travel underground. The approach makes it possible to start out with some level of risk - such as a 50 percent chance of 30 households experiencing shaking that feels exciting but not frightening, based on community questionnaires - and calculate the largest earthquake magnitude that would keep risk at or below that level.

The authors propose using this type of analysis as a starting point for managing earthquake risk caused by fracking using a system known as a traffic-light protocol. Adopted in states including Ohio and Oklahoma to manage seismic hazards related to oil, gas and some geothermal energy development, traffic-light protocols give operators a green light to proceed as long as quakes remain relatively small. Larger earthquakes may require an operator to adjust or halt fluid injections, knowing that shaking may continue and even intensify after the pumps shut down.

"If the goal is to treat everyone equally in terms of risk, our analysis shows action should be taken at lower magnitudes for drill sites near the cities in the north of the Eagle Ford than for those in rural areas in the south," explained Ellsworth, who is also a co-director of SCITS.

According to the researchers, it's "unfair" to set a uniform threshold for the amount of shaking allowed across a large formation like the Eagle Ford. "Single valued thresholds can allow for thresholds that are too permissive in urban regions or too restrictive in rural regions," said Beroza, the Wayne Loel Professor at Stanford Earth. "Instead, if you start with a tolerance to risk, you can set thresholds that vary according to changes in the risk."