Culture

Living in an essentially zero-gravity environment, many deep-sea animals have evolved soft, gelatinous bodies and collect food using elaborate mucus filters. Until now, studying these delicate structures has been virtually impossible. A new study published in the journal Nature describes a unique laser-based system for constructing 3D models of diaphanous marine animals and the mucus structures they secrete.

According to Kakani Katija, MBARI Principal Engineer and the lead author on the new paper, "Mucus is ubiquitous in the ocean, and complex mucus structures are made by animals for feeding, health, and protection. Now that we have a way to visualize these structures deep below the surface we can finally understand how they function and what roles they play in the ocean."

For this study, the researchers focused on one of the most prolific mucus architects, deep-sea animals called larvaceans. Larvaceans are abundant throughout the world's ocean basins and range from less than one centimeter to about 10 centimeters in length. So-called "giant" larvaceans create balloon-like mucus webs that can be up to a meter across. Inside these outer filters are smaller, fist-sized inner filters that the animals use to feed on tiny particles and organisms, ranging from less than a micron to a few millimeters in size.

Despite their insubstantial bodies, larvaceans remove vast amounts of carbon-rich food out of the surrounding water. When their mucus filters become clogged the animals release the mucus, which sinks rapidly to the seafloor. This helps the ocean remove carbon dioxide from the atmosphere and carries microplastics from the water column down to the seafloor.

Researchers, like MBARI Senior Scientist and co-author Bruce Robison, have long been interested in how larvaceans can filter a wide variety of particles while processing very large volumes of water (up to 80 liters an hour). Previous studies have looked at smaller larvacean filters in the laboratory, but this is the first study to provide quantitative data about these mucus structures in the open ocean.

To gather these data, Katija, who heads MBARI's Bioinspiration Lab, worked with a team of engineers, scientists, and submersible pilots to develop an instrument called DeepPIV (PIV stands for particle imaging velocimetry). Mounted on a remotely operated vehicle (ROV), the DeepPIV instrument projects a sheet of laser light that illuminates particles in the water, like dust motes in a sunbeam. By recording the movement of these particles in video, researchers can quantify tiny currents around marine animals as well as water flowing through their filters and their transparent bodies.

During field deployments of the DeepPIV system, Katija and her colleagues discovered that, as the ROV moved back and forth, the sheet of laser light revealed a series of cross sections through the transparent, gelatinous bodies and the mucus filters of giant larvaceans. By assembling a series of these cross-sectional images, the team was able to create three-dimensional reconstructions of individual larvaceans and their filters, much as radiologists do following a CAT scan of a human body.

Collecting high-fidelity video imagery required skilled piloting of MBARI's ROVs. "Using DeepPIV to collect these 3D cross sections is probably the hardest thing I've ever done with an ROV," said Knute Brekke, chief pilot for ROV Doc Ricketts. "We were using a 12,000 pound robot to move a millimeter-thick laser sheet back and forth through a larvacean and its fist-sized mucus filter that was drifting hundreds of meters below the ocean surface."

Combining three-dimensional models of larvacean filters with observations of flow patterns through the filters, Katija and her collaborators were able, for the first time, to identify the shape and function of different parts of the larvacean's inner filter. Using 3D rendering software, they were able to virtually "fly through" the inner filter and study the flow of fluid and particles through different parts of the filter.

"Now we have a technique for understanding the form of these complex structures, and how they function," Katija explained. "No one has done in situ 3D reconstructions of mucus forms like this before."

"Among other things, we're hoping to understand how larvaceans build and inflate these structures," she continued. "This could help us design better 3D printers or build complex inflatable structures that could be used in a number of environments," including underwater and in outer space.

Expanding on this work, members of the Bioinspiration Lab are experimenting with new 3D plenoptic imaging systems that can capture highly-precise information about the intensity, color, and direction of light in a scene. They are also collaborating on the development of new underwater robots that will be able to follow gelatinous animals through the water for hours or days at a time.

"In this paper, we have demonstrated a new system that operates well with a variety of underwater vehicles and midwater organisms," said Katija. "Now that we have a tool to study the mucus filtering systems found throughout the ocean, we can finally bring to light some of nature's most complex structures."

"DeepPIV has revealed a marvel of natural engineering in the structure of these complex and intricate filtering webs," said Robison. "And in DeepPIV, human engineering has produced a powerful new tool for investigating these and other mysteries of the deep ocean."

What The Study Did: The immunologic features of mild and moderate COVID-19 in pediatric patients is described and compared in this case series.

Authors: Yun Xiang, Ph.D., and Jianbo Shao, Ph.D., of the Wuhan Children's Hospital in China, are the corresponding authors.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2020.10895)

Editor's Note: The article includes funding/support disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflicts of interest and financial disclosures, and funding and support.

MADISON -Using the Wisconsin H-Alpha Mapper telescope, astronomers have for the first time measured the Fermi Bubbles in the visible light spectrum. The Fermi Bubbles are two enormous outflows of high-energy gas that emanate from the Milky Way and the finding refines our understanding of the properties of these mysterious blobs.

The research team from the University of Wisconsin-Madison, UW-Whitewater and Embry-Riddle Aeronautical University measured the emission of light from hydrogen and nitrogen in the Fermi Bubbles at the same position as recent ultraviolet absorption measurements made by the Hubble Telescope.

"We combined those two measurements of emission and absorption to estimate the density, pressure and temperature of the ionized gas, and that lets us better understand where this gas is coming from," says Dhanesh Krishnarao, lead author of the new study and an astronomy graduate student at UW-Madison.

The researchers announced their findings June 3 at the 236th meeting of the American Astronomical Society, which was held virtually for the first time since 1899, in response to the COVID-19 pandemic.

Extending 25,000 light years both above and below the center of the Milky Way, the Fermi Bubbles were discovered in 2010 by the Fermi Gamma Ray Telescope. These faint but highly energetic outflows of gas are racing away from the center of the Milky Way at millions of miles per hour. But while the origin of the phenomenon has been inferred to date back several million years ago, the events that produced the bubbles remain a mystery.

Now, with new measurements of the density and pressure of the ionized gas, researchers can test models of the Fermi Bubbles against observations.

"The other significant thing is that we now have the possibility of measuring the density and pressure and the velocity structure in many locations," with the all-sky WHAM telescope, says Bob Benjamin, a professor of astronomy at UW-Whitewater and co-author of the study. "We can do an extensive mapping effort across the Fermi Bubbles above and below the plane of the galaxy to see if the models that people have developed are holding up. Because, unlike the ultraviolet data, we're not limited to just specific lines of sight."

Matt Haffner, professor of physics and astronomy at Embry-Riddle Aeronautical University and a co-author of the report, says the work demonstrates the usefulness of the WHAM telescope, developed at UW-Madison, to tell us more about the workings of the Milky Way. The central region of our home galaxy has long been difficult to study because of gas blocking out view, but WHAM has provided new opportunities to gather the kind of information we have for distant galaxies.

"There are regions of the galaxy we can target with very sensitive instruments like WHAM to get this kind of new information toward the center that previously we are only able to do in the infrared and radio," says Haffner. "We can make comparisons to other galaxies by making the same kind of measurements towards the center of the Milky Way."

Canadian scientists have achieved a first in the study of telomerase, an essential enzyme implicated in aging and cancer.

In today's edition of the prestigious journal Molecular Cell, scientists from Université de Montréal used advanced microscopy techniques to see single molecules of telomerase in living cells.

A flaw in the replication of chromosomes means that they get shorter with each cell division. If nothing is done to correct this error, replication stops and cells go into a state called senescence, a hallmark of aging. Normally, telomerase adds extra DNA to the ends of chromosomes to prevent this problem, but as we age our bodies produce fewer of them.

Cancer cells, on the other hand, become immortal by switching telomerase back on, allowing cells to divide indefinitely. This re-activation is among the first steps that direct cells to become cancerous, but the process remains poorly understood. If researchers knew more about it, they could offer hope for some form of therapy to combat it.

Now an Université de Montréal team led by biochemistry professor Pascal Chartrand, in collaboration with cell biologist Agnel Sfeir at the Skirball Institute in New York, has succeeded in tagging telomerase with several ultrabright fluorescent molecules - something that's never been done before.

"With this technological breakthrough, we observed that telomerase continuously probes telomeres, but becomes engaged at the ends of chromosomes following a two-step binding mode," said UdeM biochemist Hadrien Laprade, who, with his colleague Emmanuelle Querido, conducted the experimental investigations.

In their study, the scientists also show how mutation of a telomeric regulatory factor results in an unrestrained access of telomerase to the tips of telomeres, an event that promotes tumorigenesis.

"This new technology now provides sufficient details of how a key actor in cancer works at the molecular level, the first step in developing novels therapeutic strategies to thwart its activity," said Chartrand.

"It could take years before we get there, but this is an important first step."

What The Study Did: Epidemiology, clinical and laboratory features of 50 children hospitalized with COVID-19 in New York are examined in this case series.

Authors: Philip Zachariah, M.D., M.Sc., of Columbia University Irving Medical Center in New York, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamapediatrics.2020.2430)

Editor's Note: The article includes conflict of interest disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflicts of interest and financial disclosures, and funding and support.

A cautious approach to easing lockdown restrictions that reduces the risk of later lockdowns may be better for the global supply chain in the long run, according to a new modelling study led by UCL and Tsinghua University.

The paper, published today in Nature Human Behaviour, is the first peer-reviewed study to comprehensively assess potential global supply chain effects of Covid-19 lockdowns, modelling the impact of lockdowns on 140 countries, including countries not directly affected by Covid-19.

The study found that stricter lockdowns imposed earlier - such as the two-month lockdown imposed in China - are economically preferable to more moderate lockdowns imposed for four or six months, as duration of lockdown matters more to economies than their severity. This is because businesses can absorb the shock of a brief lockdown better by relying on reserves and because shorter lockdowns cause less disruption to regional and global supply chains.

Researchers also found that countries not directly affected by Covid-19 may nonetheless experience large losses of more than 20% of their GDP due to falls in consumer demand and bottlenecks in supply chains.

Particularly at risk are open or highly specialised economies, such as Caribbean countries that rely on tourism and Central Asian countries such as Kazakhstan that rely on energy exports. Also vulnerable are globalised industries that rely on difficult-to-replace suppliers, such as automobile manufacturing, where production is estimated to fall by up to half.

Lead author Professor Dabo Guan (UCL Bartlett School of Construction & Project Management and Tsinghua University) said: "Our study shows the ripple effects caused by lockdowns along global supply chains, with countries not directly affected by Covid-19 still experiencing heavy economic losses.

"While predicting the true cost of lockdowns is not possible at this stage, our research suggests that shorter, stricter lockdowns minimise the impact on supply chains, while gradually easing restrictions over the course of a year may also be less disruptive than a swift lifting of restrictions followed by another lockdown."

The researchers estimated that gradually easing lockdown measures over 12 months would minimise supply chain impacts compared to lifting restrictions more quickly, over two months, and then introducing a second round of lockdowns in January next year, which they estimated would increase the cost by one-third.

Co-author Professor Steven Davis (University of California, Irvine) said: "Our analysis quantifies the global economic benefits of robust public health responses and suggests that economic justifications to re-open businesses could backfire if they result in another round of lockdowns."

Looking ahead to a potential second wave, the researchers found that a strict, globally co-ordinated lockdown implemented for two months would be less economically costly than lockdowns happening in different parts of the world at different times - risking a potential economic loss to global supply chains by 50% rather than 60%. This is because the economic cost of a lockdown goes beyond national borders and a shorter, one-off shock is easier to absorb.

Professor Guan said: "Companies will survive the supply chain failures that lockdowns cause by relying on reserves of stock or finding new suppliers. If a second shock hits, reserves may be low and supply chains only recently repaired - making a new break much more costly."

If recurrent global lockdowns occur, New Zealand's food services sector and Jamaica's tourism industry would face estimated productivity losses of about 90%, while China's electronics business and Iran's oil industry would face productivity losses of about two thirds.

The cost to the UK economy, meanwhile, would rise from a potential supply chain loss of 38% (one lockdown gradually eased over 12 months) to 57% (recurrent global lockdowns happening at different times in different countries).

In the United States, the cost to the financial sector would nearly double if a second global lockdown occurs, with potential supply chain loss rising from 33% (one lockdown gradually eased over 12 months) to 57% (recurrent global lockdowns happening at different times in different countries).

The most important factor affecting the global economic cost of lockdowns, the study found, was the number of countries implementing them, highlighting the importance to the global economy of one country containing an epidemic.

Co-author Professor D'Maris Coffman (UCL Bartlett School of Construction & Project Management) said: "Just as individuals staying at home protect others as well as themselves, so countries imposing strict lockdowns provide a public good to other countries.

"In preparing for the next pandemic, a global facility, in all likelihood administered by the IMF, could ensure that the costs of containing an outbreak are not borne by one country alone. This would remove some of the disincentives to early action and provide enormous health and economic benefits over the long term."

The paper used a "disaster footprint" economic model to quantify the direct costs of lockdowns in terms of labour reduction as well as the cascading effects of loss of labour on the supply chain, simulating how constraints to output affect upstream suppliers as well as the firms to which the goods are being supplied. Supply chain data was drawn from the Global Trade Analysis Project (GTAP) database, which divides the world into 141 economies, with 60 sectors within each economy.

Researchers simulated three kinds of lockdown: strict lockdown in which 80% of travel and labour ceases; a more moderate lockdown with a 60% reduction; a third, lighter lockdown with a 40% reduction in travel and labour. The strict, 80% reduction is based roughly on China's lockdown, during which data suggests 80% of travel stopped, while the 60% lockdown broadly reflects the approach taken in Europe and the United States.

A joint team, while exploring phase diagrams in dense H2-HD-D2 mixtures, has reported a new discovery in which they found counterintuitive effects of isotopic doping on the phase diagram of H2-HD-D2 molecular alloy.

This work was conducted by a research team at the Institute of Solid State Physics, Hefei Institutes of Physical Science collaborating with researchers from the Center for High Pressure Science & Technology Advanced Research and University of Edinburgh. It was published in PNAS on 2 June, 2020.

Molecular hydrogen forms the archetypical quantum solid. Its quantum nature is revealed by classically impossible behavior as well as by very strong isotope effects. Isotope effects between H2, D2, and HD molecules come from mass difference and the different quantum exchange effects: Fermionic H2 molecules have antisymmetric wavefunctions, while bosonic D2 molecules have symmetric wavefunctions, and HD molecules have no exchange symmetry.

To investigate how the phase diagram depends on quantum-nuclear effects, the joint team used high-pressure and low-temperature in situ Raman spectroscopy to map out the phase diagrams of H2-HD-D2 with various isotope concentrations over a wide P-T range.

When hydrogen and deuterium were mixed, they formed H2 + HD + D2 mixtures at very low pressures and room temperature.

They found that mixtures of H2, HD, and D2 behaved as an isotopic molecular alloy (ideal solution) and exhibited symmetry-breaking phase transitions between phases I and II and phase III.

In their experiment, the researchers were surprised to find that all transitions occurred at higher pressures for the alloys than for either pure H2 or D2. This ran counter to any quantum effects based on isotope mass but could be explained by quantum trapping of high-kinetic energy states by the exchange interaction.

"Since HD has an intermediate mass and prevalent component in these alloys, one would expect that with its addition phase transitions would occur at intermediate P-T regimes", said the leading scientist of this study, "The discrepancy from the more classical understanding of molecular phase diagrams, derives from the quantum nature of the hydrogen molecules themselves, where the exchange-symmetry can in effect trap the molecules in different, higher energy states."

"HD molecules have no exchange symmetry, at low temperature all HD molecules will be in the lowest energy state. However, pure H2 and D2 have exchange symmetry, so some of the molecules would be trapped in the higher energy states. So the trapped kinetic energy is lower in mixtures than in either pure elements, and it shifts the phase transition to higher pressure in mixtures", said LIU Xiaodi, the first author of the paper.

This work was supported by the National Natural Science Foundation of China, the CAS President's International Fellowship Initiative, the Science Challenge Project, the CAS Innovation Fund and the Director's Fund of Science Island.

A new mobile app can help clinicians determine which patients with the novel coronavirus (COVID-19) are likely to have severe cases. Created by researchers at NYU College of Dentistry, the app uses artificial intelligence (AI) to assess risk factors and key biomarkers from blood tests, producing a COVID-19 "severity score."

Current diagnostic tests for COVID-19 detect viral RNA to determine whether someone does or does not have the virus--but they do not provide clues as to how sick a COVID-positive patient may become.

"Identifying and monitoring those at risk for severe cases could help hospitals prioritize care and allocate resources like ICU beds and ventilators. Likewise, knowing who is at low risk for complications could help reduce hospital admissions while these patients are safely managed at home," said John T. McDevitt, PhD, professor of biomaterials at NYU College of Dentistry, who led the research.

"We want doctors to have both the information they need and the infrastructure required to save lives. COVID-19 has challenged both of these key areas."

Creating a Severity Score

Using data from 160 hospitalized COVID-19 patients in Wuhan, China, the researchers identified four biomarkers measured in blood tests that were significantly elevated in patients who died versus those who recovered: C-reactive protein (CRP), myoglobin (MYO), procalcitonin (PCT), and cardiac troponin I (cTnI). These biomarkers can signal complications that are relevant to COVID-19, including acute inflammation, lower respiratory tract infection, and poor cardiovascular health.

The researchers then built a model using the biomarkers as well as age and sex, two established risk factors. They trained the model using a machine learning algorithm, a type of AI, to define the patterns of COVID-19 disease and predict its severity. When a patient's biomarkers and risk factors are entered into the model, it produces a numerical COVID-19 severity score ranging from 0 (mild or moderate) to 100 (critical).

The model was validated using data from 12 hospitalized COVID-19 patients from Shenzhen, China, which confirmed that the model's severity scores were significantly higher for the patients that died versus those who were discharged. These findings are published in Lab on a Chip, a journal of the Royal Society of Chemistry.

As New York City emerged as the epicenter of the pandemic, the researchers further validated the model using data from more than 1,000 New York City COVID-19 patients. To make the tool available and convenient for clinicians, they developed a mobile app that can be used at point-of-care to quickly calculate a patient's severity score.

A Clinical Decision Support Tool

The app has been retrospectively evaluated in the Family Health Centers at NYU Langone in Brooklyn, which serve more than 102,000 patients each year as one of the nation's largest Federally Qualified Health Center networks.

"Real time clinical decision support tools for COVID-19 can be extremely helpful, particularly in the outpatient setting, to help guide monitoring and treatment plans for those at greatest risk," said Isaac P. Dapkins, MD, chief medical officer for the Family Health Centers at NYU Langone and a co-author on the Lab on a Chip study.

After optimizing the clinical utility of the app at the Family Health Centers at NYU Langone in May, the researchers aim to roll it out nationwide in the coming weeks. It is possible that the COVID-19 severity score could be integrated with electronic health records, thereby providing clinicians with actionable information at an early stage for those diagnosed with COVID-19.

"We hope this tool can help identify those at high risk for adverse outcomes and reduce the health disparities present with COVID-19," said Larry K. McReynolds, executive director for the Family Health Centers at NYU Langone.

Building on Innovations in Testing

The COVID-19 severity score leverages a model McDevitt previously developed to predict outcomes for patients with cardiac disease. Cardiac health is one of several priorities of McDevitt's lab, which creates point-of-care diagnostic systems that can be programmed to test for oral cancer, cardiac disease, and now COVID-19 biomarkers.

The diagnostic system uses small, non-invasive samples--such as swabs of saliva or drops of blood from a fingertip--which are added to credit card-sized cartridges armed with bio-nano-chips pioneered by McDevitt. The cartridge is inserted into a portable analyzer that simultaneously tests for a range of biomarkers, with results available in less than half an hour.

Because this technology is currently used for research and informational purposes only, the COVID-19 app can be used with existing laboratory tests and requires oversight by an authorized clinician. However, over the next few months, McDevitt's laboratory, in partnership with SensoDx, a company spun out of his lab, plans to develop and scale the ability to test a drop of blood for COVID-19 severity biomarkers--similar to how a person with diabetes tests their blood sugar--and produce a severity score on the spot.

"With COVID-19, point-of-care testing, coupled with a decision support system, could improve how clinicians triage patients--and potentially improve their outcomes, particularly for those who need more immediate and aggressive care," said McDevitt.

In addition to McDevitt's research group at NYU College of Dentistry, the study involved collaborators from NYU Grossman School of Medicine, NYU Tandon School of Engineering, Zhongnan Hospital of Wuhan University, and Latham BioPharm Group. The app was developed by McDevitt's laboratory and OraLiva, a company founded by McDevitt, and is available for both Apple and Android devices. The app is designated for use by authorized clinicians and is not intended for general use by patients.

An inflammatory syndrome in children and adolescents, believed to be linked to covid-19, seems to be more common among children of African ancestry, finds a small study from a hospital in Paris, published by The BMJ today.

The syndrome has been compared with Kawasaki disease, a rare condition which mainly affects children under five. Experts have said that it may be an "antibody mediated or delayed response" to covid-19 that happens several weeks after infection.

Cases have also been seen in Italy, the UK and the US.

In this study, patients had characteristics that differ from those with classic Kawasaki disease. For example, an unusually high proportion had gastrointestinal symptoms (abdominal pain, often with vomiting and diarrhoea), unstable blood pressure, and inflammation of the heart muscle (myocarditis).

The researchers say further studies are needed, but these findings "should prompt high vigilance" among doctors, particularly in countries with a high proportion of children of African ancestry.

They describe 21 children and adolescents (average age 7.9 years) with features of Kawasaki disease who were admitted to a hospital in Paris between 27 April and 11 May 2020. Over half of the children (12; 57%) were of African ancestry.

Twelve children presented with Kawasaki disease shock syndrome and 16 (76%) with myocarditis. Nineteen (90%) had evidence of recent covid-19 infection.

All 21 patients had noticeable gastrointestinal symptoms during the early stage of illness and high levels of inflammatory markers in their bloodstream.

Despite 17 patients (81%) needing intensive care support, all patients were discharged home by 15 May 2020, after an average of 8 days in hospital, with no serious complications.

The researchers point to some limitations, such as the small number of patients, and stress that this is an observational study, so can't establish a causal link with covid-19 infection.

Nevertheless, they say this Kawasaki-like multisystem inflammatory syndrome seems to be more common in children of African ancestry, suggesting an effect of either social and living conditions or genetic susceptibility, and shows different clinical symptoms to classic Kawasaki disease.

"These clinical findings should prompt high vigilance among primary care and emergency doctors, and preparedness during the coronavirus disease 2019 pandemic in countries with a high proportion of children of African ancestry and high levels of community transmission," they conclude.

The researchers have added an important layer to the growing knowledge of this disorder, strengthening the connection between covid-19 infection and this condition, says Mary Beth Son at Boston Children's Hospital, in a linked editorial. She stresses that this condition is so far rare but potentially severe, and warrants surveillance as well as collaborative research.

It seems highly likely that more reports will appear from around the globe, she warns, but says the rapid release of publications such as this, "is the first step in this critical process."

We can all picture that incredible image of a black hole that travelled around the world about a year ago. Yet, according to new research by SISSA, ICTP and INFN, black holes could be like a hologram, where all the information is amassed in a two-dimensional surface able to reproduce a three-dimensional image. In this way, these cosmic bodies, as affirmed by quantum theories, could be incredibly complex and concentrate an enormous amount of information inside themselves, as the largest hard disk that exists in nature, in two dimensions. This idea aligns with Einstein's theory of relativity, which describes black holes as three dimensional, simple, spherical, and smooth, as they appear in that famous image. In short, black holes "appear" as three dimensional, just like holograms. The study which demonstrates it, and which unites two discordant theories, has recently been published in Physical Review X.

The mystery of black holes

For scientists, black holes are a big question mark for many reasons. They are, for example, excellent representatives of the great difficulties of theoretical physics in putting together the principles of Einstein's general theory of relativity with those of quantum physics when it comes to gravity. According to the first theory, they would be simple bodies without information. According to the other, as claimed by Jacob Bekenstein and Stephen Hawking, they would be "the most complex existing systems" because they would be characterised by an enormous "entropy", which measures the complexity of a system, and consequently would have a lot of information inside them.

The holographic principle applied to black holes

To study black holes, the two authors of the research, Francesco Benini (SISSA Professor, ICTP scientific consultant and INFN researcher) and Paolo Milan (SISSA and INFN researcher), used an idea almost 30 years old, but still surprising, called the "holographic principle". The researchers say: "This revolutionary and somewhat counterintuitive principle proposes that the behavior of gravity in a given region of space can alternatively be described in terms of a different system, which lives only along the edge of that region and therefore in a one less dimension. And, more importantly, in this alternative description (called holographic) gravity does not appear explicitly. In other words, the holographic principle allows us to describe gravity using a language that does not contain gravity, thus avoiding friction with quantum mechanics".

What Benini and Milan have done "is apply the theory of the holographic principle to black holes. In this way, their mysterious thermodynamic properties have become more understandable: focusing on predicting that these bodies have a great entropy and observing them in terms of quantum mechanics, you can describe them just like a hologram: they have two dimensions, in which gravity disappears, but they reproduce an object in three dimensions".

From theory to observation

"This study," explain the two scientists, "is only the first step towards a deeper understanding of these cosmic bodies and of the properties that characterise them when quantum mechanics crosses with general relativity. Everything is more important now at a time when observations in astrophysics are experiencing an incredible development. Just think of the observation of gravitational waves from the fusion of black holes result of the collaboration between LIGO and Virgo or, indeed, that of the black hole made by the Event Horizon Telescope that produced this extraordinary image. In the near future, we may be able to test our theoretical predictions regarding quantum gravity, such as those made in this study, by observation. And this, from a scientific point of view, would be something absolutely exceptional".

Scientists have long tried to experimentally demonstrate a certain symmetry property of the weak interaction - parity violation - in molecules. So far, this has not been possible. A new interdisciplinary effort led by a research group at the at the PRISMA+ Cluster of Excellence at Johannes Gutenberg University Mainz (JGU) and the Helmholtz Institute Mainz (HIM) has now shown a realistic path to demonstrating this phenomenon. The approach includes aspects of nuclear, elementary particle, atomic and molecular physics as well as nuclear magnetic resonance (NMR). "Molecular parity nonconservation in nuclear spin couplings" is published in the current issue of the journal Physical Review Research.

Symmetries are omnipresent - in space as well as in the world of molecules, atoms and elementary particles. The four fundamental forces (electromagnetism, gravity, and the strong and weak nuclear forces) also obey certain, perhaps seemingly abstract, symmetries. From the Big Bang to the present day, existing symmetries were repeatedly broken. Symmetry and symmetry breaking are necessarily reflected in the physical processes and states that we can observe.

One of these symmetries is the mirror symmetry (symmetry with regard to reflection in space) - if it is broken, the researchers speak of parity violation. According to current knowledge, the weak interaction is the only one among the four fundamental forces that does not appear mirror-symmetrical: Only in processes that are subject to this interaction do parity violations occur. "Since the weak interaction plays almost no role in our everyday experience - gravity and electromagnetism dominate here - the phenomenon of parity violation contradicts our normal idea and is therefore difficult to grasp," says Dr. John Blanchard, lead author of the study. "Parity violation in the weak interaction was therefore only theoretically predicted in the 1950s and was discovered shortly afterwards in certain nuclear and elementary particle decays. Parity-violating processes have never been detected in molecules, although theoretical calculations predict that they should be there. Definitive evidence of such subtle effects is, so to speak, a holy grail of precision-measurement physics."

Many attempts have been made to experimentally observe the effects of parity violation in molecules. One example is the interaction of the spins of different atomic nuclei in a molecule. In turn, these can in principle be detected and analyzed using nuclear magnetic resonance methods (NMR). While the team of scientists has already developed a promising approach to chiral molecules in a previous work, their current publication focuses on simple molecules that consist of as few as two atoms. First of all, they identify a special NMR measurement variable (a specific spin-spin coupling) on the basis of which the parity violation is shown and carry out complex theoretical analyses to calculate the expected effect within the molecule. These calculations were carried out in close collaboration with the co-author of the study, Prof. Mikhail G. Kozlov from the Nuclear Physics Institute in St. Petersburg, Russia, with whom the Mainz group has been working very successfully for many years.

Building on this, the scientists propose a special experiment that should be sensitive enough to detect the calculated signals: "The so-called ZULF (zero to ultra-low field) NMR method is an exotic technique that we were already using for dark matter successfully," explains Prof. Dr. Dmitry Budker, also an author of the study. "It offers a system in which nuclear spins interact with each other more than with an external magnetic field. In this way, it enables the direct measurement of antisymmetric spin-spin couplings, which are cut off in conventional high-field NMR experiments."

"Our results show an elegant way to quantitatively investigate the weak interaction in molecules and atomic nuclei," concludes Dr. Blanchard. "The results of our feasibility study are very promising - we hope to soon have experimental verification of molecular parity nonconservation."

Scientists at Johannes Gutenberg University Mainz (JGU) in Germany have developed a new sustainable method of extracting the flavoring agent vanillin from lignin, a component of wood. Large quantities of waste lignin accumulate during the production of pulp, an important raw material for making paper. The process the researchers describe in their article in ACS Sustainable Chemistry & Engineering involves dissolving the lignin in caustic soda and heating this mixture to 160 degrees Celsius in a simple electrolysis cell with nickel electrodes to which a current is applied. This oxidizes and breaks down the lignin to produce vanillin of such a high quality in a reagent-less process that it cannot be distinguished from natural vanillin. "After many years of intensive research, we have now made a real breakthrough," said Prof. Siegfried Waldvogel, coordinator of the SusInnoScience (Sustainable Chemistry as the Key to Innovation in Resource-efficient Science in the Anthropocene) research focus at JGU, who developed the project. To date, vanillin has been predominantly made from petroleum, a process which, in contrast to this new method, produces toxic waste difficult to dispose of. There is in fact already a process for producing vanillin from lignin. However, according to Waldvogel, this is much more expensive, not least as it requires the use of copper. Furthermore, only a small proportion of the waste stream of lignin from pulp production can be processed using this method.

In terms of quantity, vanillin is the most important flavoring and aroma agent in the world. Many tens of thousands of tons of it are used every year in the production of food and cosmetics as well as in the synthesis of pharmaceuticals. On the other hand, more than 100 million tons of lignin is generated as waste in pulp production each year to be then mainly thermally exploited. "Because our method has a vanillin yield of around four percent of the lignin used, it could theoretically meet the global demand for vanillin very easily," said Waldvogel. He is convinced that the new process is "significantly better" than the previous methods of vanillin extraction - not only because no toxic waste is produced, but also because it is more commercially viable - and he is already in discussions with relevant business partners. As part of the LIBERATE project funded by the European Union (EU), the method, which has so far only been used in the laboratory, will soon be tested on an industrial scale. A pilot plant is currently being built for this very purpose at the Norwegian research institute SINTEF, with which JGU is cooperating. In addition, Waldvogel wants to determine whether the new method can be further improved by producing vanillin not only from pure lignin, but directly from the so-called black liquor, a byproduct of wood processing in pulp mills also containing lignin.

Gesture is an integral part of language development. Recent studies carried out by the same authors in collaboration with other members of the Prosodic Studies Group (GrEP) coordinated by Pilar Prieto, ICREA research professor Department of Translation and Language Sciences at UPF, have shown that when the speaker accompanies oral communication with rhythmic gesture, preschool children are observed to better understand the message and improve their oral skills. A new study goes a step further and studies for the first time the potential value of the fact that children produce rhythmic gestures while expressing themselves orally.

"In this study, we investigated whether encouraging children to produce rhythmic gestures can help improve the quality of their oral storytelling", explains Ingrid Vilà-Giménez, first author of the paper and member of Pilar Prieto's research team, co-author of the work recently published in the journal Developmental Science. To conduct this research, the authors studied the behaviour of 47 children aged 5 to 6.

To study the children's oral narrative skills, the children were divided into two groups and received a training session in which they were presented with a total of six animated cartoon stories under one of the two experimental conditions. One group of children was limited to observing video recordings by narrators accompanying the stories using rhythmic gestures, and then the children had to re-enact the story they had been told. The other group was asked to perform the same task, but then they were asked to explain the stories helping themselves by using hand movements, just as they had seen it being done by the narrators of the stories in the recording.

The researchers analysed the stories about the animated cartoons, looking at structure and narrative flow, and compared the scores obtained between the two experimental groups. The results showed that the children from the group that had used rhythmic gestures in the training phase achieved improvements in their oral narrative skills, both from the point of view of narrative structure and from the point of view fluency, compared to the group of children who were asked to simply retell the story without receiving any instructions regarding the production of gestures.

These results show that encouraging children to use rhythmic gestures while narrating a story helps to improve the quality of their narrations and, consequently, their oral skills. The study suggests that body movements are linguistically relevant because they play an important role in the development of language. In short, a multimodal training where children narrate stories using rhythmic gestures can help improve their oral narrative skills.

The use of antiepileptic drugs is associated with a higher risk of death among persons with Alzheimer's disease, according to a new study from the University of Eastern Finland. The results were published in Neurology. The mortality risk increased considerably during the first three months of treatment with antiepileptic drugs, and was higher among users of older antiepileptic drugs in comparison to users of newer antiepileptics. The risk of death remained elevated after exclusion of people with epilepsy in the sensitivity analyses.

The increased risk remained after controlling for comorbidities, sociodemographic factors and the use of other drugs. However, it is possible that the reasons for initiating an antiepileptic partially explain the results and, therefore, the findings should be confirmed in further studies.

These initial findings are concerning, as people with Alzheimer's disease used antiepileptic drugs more frequently than people without the disease, and the use of older antiepileptics is more common among them. The association between antiepileptic use and mortality in this population has not been studied before.

The results highlight caution in prescribing these drugs for indications other than epilepsy in this vulnerable group. Up to 1% of the population needs chronic antiepileptic treatment to control epilepsy. These drugs are also frequently used for other indications, including neuropathic pain and behavioural and psychological symptoms of dementia, although antiepileptics are not officially indicated for behavioural and psychological symptoms of dementia.

The studies are based on the Finnish nationwide MEDALZ dataset, which includes all community-dwelling persons with Alzheimer's disease in Finland during 2005-2011 (70,718 people). Data on antiepileptic drug use was extracted from the Prescription Register. The mortality risk was compared between antiepileptic drug users and matched non-users with Alzheimer's disease. The study, funded by the Academy of Finland, was conducted at the University of Eastern Finland.

Scientists have long debated which genetic information carrier - DNA or RNA - started life on Earth, but a new study suggests life could have begun with a bit of both. The research, led by scientists from the Medical Research Council (MRC) Laboratory of Molecular Biology (LMB), in Cambridge, shows for the first time how some of the building blocks of both DNA and RNA could have spontaneously formed and co-existed in the 'primordial soup' on Earth.

The work challenges one of the leading hypotheses for the advent of life - the 'RNA world' theory, which arose in the 60s and has gained wide acceptance.

Today, all known living organisms use the same genetic molecules - called nucleic acids - to store information. There are two sorts of nucleic acids: DNA and RNA. DNA encodes instructions in genes. Genes are turned into messages using RNA, which carries instructions to make proteins. Proteins can make structures and act as molecular machines.

In the 'RNA world' theory, life started with RNA molecules, which can both store instructions and can act as a modest machine, potentially enabling them to self-replicate. It proposes that through evolution, life in the RNA world gave way to the era of DNA and proteins, because DNA is more stable and durable than RNA.

In the current study, published in Nature, the researchers simulated the conditions on a primordial rocky Earth with shallow ponds in the lab. They dissolved chemicals that form RNA in water, then dried them out and heated them, then they simulated the early sun's rays by exposing them to UV radiation.

In this recreation of early Earth geochemistry, intermediates in the synthesis of two of the building blocks of RNA were simultaneously also converted into two of the building blocks of DNA.

It is the first demonstration that reasonable amounts of a genetic alphabet made up of four building blocks, two for RNA and two for DNA - potentially sufficient to have encoded early life, which was far less complex than life today - may have been available on the primordial Earth.

Professor John Sutherland from the MRC Laboratory of Molecular Biology, who led the work, says: "The RNA world hypothesis suggests that life began with RNA, before a genetic takeover occurred involving primitive biosynthetic machinery and natural selection to result in DNA."

"Our work suggests that in conditions consistent with shallow primordial ponds and rivulets there was a mixed genetic system with RNA and DNA building blocks co-existing at the dawn of life. This fulfils what many people think is a key precondition for the spontaneous emergence of life on Earth."

The team's experiments to simulate early Earth geochemistry showed that four of the building blocks for DNA and RNA can arise from the same reagents and conditions. They produced cytidine and uridine, two of the building blocks of RNA, and deoxyadenosine, which is one of those of DNA. Deoxyadenosine was partly converted to deoxyinosine, which can take the role of another DNA building block.

They believe that these four building blocks may have coexisted before life evolved and were the beginnings of a primitive genetic alphabet.

Professor Sutherland adds: "The nucleic acids, RNA and DNA, are clearly related and this work suggests that they both derive from a hybrid ancestor, rather than one preceding the other."

"Since genetic information always flows from nucleic acids to proteins, and never in reverse - a principle called the 'central dogma' of molecular biology by Francis Crick - we now need to uncover how the information which can be stored and purveyed by these nucleic acids could have been first used to make to proteins."

Understanding the chemical origins of life is a fundamental aspect of natural science, and can inform the design of future synthetic biology.

Dr Megan Dowie, head of molecular and cellular medicine at the MRC commented: "This study shows that blue skies research can reveal fascinating insights into how the very beginnings of life may have emerged, and demonstrates the importance of supporting fundamental research. These underpinning discoveries in the life sciences could enable exciting future strategies for artificial biology."