Daily Archives: 21 Nov 2020

Astronomy

Astronomers Discover New “Fossil Galaxy” Buried Deep Within the Milky Way (Astronomy)

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Scientists working with data from the Sloan Digital Sky Surveys’ Apache Point Observatory Galactic Evolution Experiment (APOGEE) have discovered a “fossil galaxy” hidden in the depths of our own Milky Way.

An artist’s impression of what the Milky Way might look like seen from above. The colored rings show the rough extent of the fossil galaxy known as Heracles. The yellow dot shows the position of the sun. Credit: Danny Horta-Darrington (Liverpool John Moores University), NASA/JPL-Caltech, and the SDSS

This result, published today in Monthly Notices of the Royal Astronomical Society, may shake up our understanding of how the Milky Way grew into the galaxy we see today.

The proposed fossil galaxy may have collided with the Milky Way ten billion years ago, when our galaxy was still in its infancy. Astronomers named it Heracles, after the ancient Greek hero who received the gift of immortality when the Milky Way was created.

The remnants of Heracles account for about one third of the Milky Way’s spherical halo. But if stars and gas from Heracles make up such a large percentage of the galactic halo, why didn’t we see it before? The answer lies in its location deep inside the Milky Way.

“To find a fossil galaxy like this one, we had to look at the detailed chemical makeup and motions of tens of thousands of stars,” says Ricardo Schiavon from Liverpool John Moores University (LJMU) in the UK, a key member of the research team. “That is especially hard to do for stars in the center of the Milky Way, because they are hidden from view by clouds of interstellar dust. APOGEE lets us pierce through that dust and see deeper into the heart of the Milky Way than ever before.”

“APOGEE lets us pierce through that dust and see deeper into the heart of the Milky Way than ever before.”, said Ricardo Schiavon.

APOGEE does this by taking spectra of stars in near-infrared light, instead of visible light, which gets obscured by dust. Over its ten-year observational life, APOGEE has measured spectra for more than half a million stars all across the Milky Way, including its previously dust-obscured core.

Graduate student Danny Horta from LJMU, the lead author of the paper announcing the result, explains, “examining such a large number of stars is necessary to find unusual stars in the densely-populated heart of the Milky Way, which is like finding needles in a haystack.”

To separate stars belonging to Heracles from those of the original Milky Way, the team made use of both chemical compositions and velocities of stars measured by the APOGEE instrument.

An all-sky image of the stars in the Milky Way as seen from Earth. The colored rings show the approximate extent of the stars that came from the fossil galaxy known as Heracles. The small objects to the lower right of the image are the Large and Small Magellanic Clouds, two small satellite galaxies of the Milky Way. Image credit: Danny Horta-Darrington (Liverpool John Moores University), ESA/Gaia, and the SDSS

“Of the tens of thousands of stars we looked at, a few hundred had strikingly different chemical compositions and velocities,” Horta said. “These stars are so different that they could only have come from another galaxy. By studying them in detail, we could trace out the precise location and history of this fossil galaxy.”

Because galaxies are built through mergers of smaller galaxies across time, the remnants of older galaxies are often spotted in the outer halo of the Milky Way, a huge but very sparse cloud of stars enveloping the main galaxy. But since our Galaxy built up from the inside out, finding the earliest mergers requires looking at the most central parts of the Milky Way’s halo, which are buried deep within the disc and bulge.

Video: This movie shows a computer simulation of a galaxy like the Milky Way. The movie fast-forwards through simulated time from 13 billion years ago to today. The main galaxy grows as many small galaxies merge with it. Heracles resembles one of the smaller galaxies that merged with the Milky Way early in the process. Credit: Ted Mackereth based on the EAGLE simulations

Stars originally belonging to Heracles account for roughly one third of the mass of the entire Milky Way halo today – meaning that this newly-discovered ancient collision must have been a major event in the history of our Galaxy. That suggests that our Galaxy may be unusual, since most similar massive spiral galaxies had much calmer early lives.

“As our cosmic home, the Milky Way is already special to us, but this ancient galaxy buried within makes it even more special,” Schiavon says.

Karen Masters, the Spokesperson for SDSS-IV comments, “APOGEE is one of the flagship surveys of the fourth phase of SDSS, and this result is an example of the amazing science that anyone can do, now that we have almost completed our ten-year mission.”

And this new age of discovery will not end with the completion of APOGEE observations. The fifth phase of the SDSS has already begun taking data, and its “Milky Way Mapper” will build on the success of APOGEE to measure spectra for ten times as many stars in all parts of the Milky Way, using near-infrared light, visible light, and sometimes both.

References: “Evidence from APOGEE for the Presence of a Major Building Block of the Halo Buried in the Inner Galaxy,” Danny Horta et al., 2020 Nov. 20, Monthly Notices of the Royal Astronomical Society: arxiv.org/abs/2007.10374]. https://arxiv.org/abs/2007.10374

Provided by Sloan Digital Sky Survey

Planetary Science

Jupiter, Saturn will look like double planet for First Time Since Middle Ages (Planetary Science)

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Just after sunset on the evening of Dec. 21, Jupiter and Saturn will appear closer together in Earth’s night sky than they have been since the Middle Ages, offering people the world over a celestial treat to ring in the winter solstice.

“Alignments between these two planets are rather rare, occurring once every 20 years or so, but this conjunction is exceptionally rare because of how close the planets will appear to one another,” said Rice University astronomer Patrick Hartigan. “You’d have to go all the way back to just before dawn on March 4, 1226, to see a closer alignment between these objects visible in the night sky.”

Jupiter and Saturn have been approaching one another in Earth’s sky since the summer. From Dec. 16-25, the two will be separated by less than the diameter of a full moon.

“On the evening of closest approach on Dec 21 they will look like a double planet, separated by only 1/5th the diameter of the full moon,” said Hartigan, a professor of physics and astronomy. “For most telescope viewers, each planet and several of their largest moons will be visible in the same field of view that evening.”

Though the best viewing conditions will be near the equator, the event will be observable anywhere on Earth, weather-permitting. Hartigan said the planetary duo will appear low in the western sky for about an hour after sunset each evening.

A view showing how the Jupiter-Saturn conjunction will appear in a telescope pointed toward the western horizon at 6 p.m. CST, Dec. 21, 2020. The image is adapted from graphics by open-source planetarium software Stellarium. (This work, “jupsat1,” is adapted from Stellarium by Patrick Hartigan, used under GPL-2.0, and provided under CC BY 4.0 courtesy of Patrick Hartigan)

“The further north a viewer is, the less time they’ll have to catch a glimpse of the conjunction before the planets sink below the horizon,” he said. Fortunately, the planets will be bright enough to be viewed in twilight, which may be the best time for many U.S. viewers to observe the conjunction.

“By the time skies are fully dark in Houston, for example, the conjunction will be just 9 degrees above the horizon,” Hartigan said. “Viewing that would be manageable if the weather cooperates and you have an unobstructed view to the southwest.”

But an hour after sunset, people looking skyward in New York or London will find the planets even closer to the horizon, about 7.5 degrees and 5.3 degrees respectively. Viewers there, and in similar latitudes, would do well to catch a glimpse of the rare astronomical sight as soon after sunset as possible, he said.

Those who prefer to wait and see Jupiter and Saturn this close together and higher in the night sky will need to stick around until March 15, 2080, Hartigan said. After that, the pair won’t make such an appearance until sometime after the year 2400.

Provided by Rice University

Astronomy

Understanding The ‘Dark’ Universe and Primordial Galaxy Formation (Astronomy)

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The Extreme-Horizon collaboration run by teams at the CEA, CNRS, Sorbonne Université and Université Paris-Saclay has produced a completely new simulation of the evolution of cosmic structures – galaxies, stars and supermassive black holes – which begins a few moments after the Big Bang and continues to the present day. It describes the intergalactic regions, which represent 90% of the Universe’s volume, in unprecedented resolution. The simulation, which leads to two surprising results at the galactic and cosmological scales, constitutes one of the main ‘grand challenges’ carried out on GENCI’s Joliot-Curie supercomputer, at the CEA’s Very Large Computing Centre (TGCC). The results were published on 4 November in MNRAS and A&A Letters.

Visible matter constitutes only 16% of the universe’s total mass. Little is known about the nature of the rest of that mass, which referred to as dark matter. Even more surprising is the fact that the universe’s total mass accounts for only 30% of its energy. The rest is dark energy, which is totally unknown but is responsible for the universe’s accelerated expansion.

To find out more about dark matter and dark energy, astrophysicists use large-scale surveys of the universe or detailed studies of the properties of galaxies. But they can only interpret their observations by comparing them to predictions by theoretical models of dark matter and dark energy. But these simulations take tens of millions of computing hours on supercomputers.

The Extreme-Horizon collaboration was able to run a simulation of the evolution of cosmic structures from the first few moments after the Big Bang to the present day, on the Joliot-Curie supercomputer, which offers computing power of 22 petaflops (22 x 10^15 floating point operations per second). The volume of numerical data processed exceeded 3TB (10¹² bytes) at each step of the computation, justifying the use of new techniques for writing (RAMSES code with adaptive mesh refinement) and reading the simulation data.

Cosmology: correcting the data from the Lyman-α forest

The simulation’s first result concerns the interpretation of large structures of the distant universe: intergalactic hydrogen clouds. Astrophysicists detect these by measuring the absorption of light from quasars, which are extremely luminous due to the presence of a supermassive black hole that attracts matter in its accretion disk. Each of the clouds along the line of sight produces an absorption line (Lyman-α) with a specific redshift, due to the expansion of the universe. All these lines form a dense forest, revealing the one-dimensional distribution of the hydrogen clouds, and therefore of matter, at distances between 10 and 12 billion light-years (ly).

However, many black holes between these quasars and us expel a considerable amount of energy into the intergalactic medium, changing its thermal state and the properties of the Lyman-α forest. The physical model used in the Extreme-Horizon simulation describes in detail this feedback, which biases estimates of cosmological parameters by several percent. The correction factor calculated will be vital, particularly for the DESI (Dark Energy Spectroscopic Instrument) experiment under construction in Arizona (U.S.), because the bias can exceed 5%, whereas the target accuracy is 1%.

Ultra-compact massive galaxies formed like a beehive

The Extreme-Horizon simulation’s high resolution in low density regions meant that it was able to describe cold gas accretion by galaxies and the formation of ultra-compact massive galaxies when the universe was only 2 to 3 billion years old. These atypical galaxies, recently observed with the Alma (Atacama Large Millimeter/Submillimeter Array) radiotelescope in Chile, are formed by the rapid clustering of many very small galaxies. It was only possible to identify this ‘beehive’ method of growth because of Extreme-Horizon’s exceptional resolution.

Grand challenge on the Joliot-Curie supercomputer

Designed by the company Atos for GENCI (the French high-performance computing center), the Joliot-Curie supercomputer, based on Atos’s BullSequana architecture, reached a peak computing power of 22 petaflops in 2020.

Grand challenges are exceptional simulations and computations carried out during the Grand Challenge period which follows the installation of a new computer partition. This three-month period provides a unique opportunity for a small number of users to access a large share of the machine’s resources. They benefit from the support of the TGCC’s and the manufacturer’s teams, working together to optimize the computer’s operation during this startup phase.

Extreme-Horizon was run on the new AMD ROME computation partition of GENCI’s Joliot-Curie supercomputer, operated by teams of computer scientists from the CEA’s Military Applications Division (DAM) at the Very Large Computing Centre (TGCC at Bruyères-Le-Châtel). The simulation took fifty million computing hours and used new data reading and writing techniques to reduce the disk space used and accelerate data access. The work was done with the support of several institutes and divisions within the CEA and of Université Paris-Saclay’s High-Performance Computing and Simulation Laboratory.

The project was run as a collaboration between CEA-Irfu, AIM (CEA, CNRS, Université de Paris), IAP (CNRS, Sorbonne Université) and LIHPC (Université Paris-Saclay, CEA-DAM).

The RAMSES simulation code is a numerical code for astrophysics and cosmology. It is based on an adaptive mesh refinement computing technique. The figure illustrates the adaptive mesh configuration based on the density of matter.
Figure 1. View of the Extreme-Horizon simulation. The red is hot gas, generally expelled from galaxies by supermassive black holes. The grey is primordial cold gas, which feeds the galaxies along the cosmic filaments. The green is gas enriched with heavy elements (metals) due to the effect of massive star explosions (supernovae)
Figure 2. View of the Extreme-Horizon simulation showing a region of 50 Mpc square. The gas temperature is shown here (violet ~10^4K – yellow ~10^7K). The main galaxies appear as cold spots within vast haloes of hot gas
Figure 3. Mass-to-size ratio of the galaxies in the Extreme-Horizon simulation (blue) compared to the ratio for the same region of the Universe re-simulated at the normal resolution of cosmological simulations (red). Extreme-Horizon reproduces the mass-to-size ratio of the galaxies observed (black curve) and explains the presence of ultra-compact galaxies (under the dashed curve) observed in the primordial Universe, through improved resolution in the diffuse medium that feeds galaxy formation.

References: (1) Solène Chabanier et al. The impact of AGN feedback on the 1D power spectra from the Ly α forest using the Horizon-AGN suite of simulations, Monthly Notices of the Royal Astronomical Society (2020). https://doi.org/10.1093/mnras/staa1242 (2) Formation of compact galaxies in the Extreme-Horizon simulation, A&A Letters, novembre 2020. https://doi.org/10.1051/0004-6361/202038614

Provided by CEA

Medicine

What Platelets and Endothelial Cells May Reveal About the Coronavirus Disease? (Medicine)

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Yale researchers have helped identify the mechanisms behind a major cause of morbidity and mortality in COVID-19 patients. Extensive blood clots in both large and small blood vessels in the lungs and throughout many major organs in the body have been linked to worse outcomes in patients hospitalized with severe COVID-19 infection. The researchers demonstrate that both platelet and endothelial dysfunction are key components of COVID-19 pathology.

Activated Platelets. Adhered and activated human platelets imaged by Confocal Microcope at Yale. ©Tarun Tyagi, PhD

A Yale team has synthesized findings from researchers worldwide, including their own cutting edge work at Yale, to propose new strategies for treatment of COVID-19 based on these cardiovascular risk factors. The review, published Nov. 19 in Nature Reviews Cardiology, was led by senior author John Hwa, MD, PhD, a professor of medicine at the Yale Cardiovascular Research Center, Sean Gu, MD, PhD, a clinical fellow in the Department of Pathology, and Tarun Tyagi, PhD, a postdoctoral associate at the Yale Cardiovascular Research Center, along with teams from Hematology, Cardiovascular Medicine, and Laboratory Medicine.

Platelets are our body’s first defense against vascular damage. A recent study in the journal Blood showed that a SARS- CoV-2 triggered platelet damage and dysfunction. Further injury to endothelial cells —the cells which line the blood and lymphatic vessels —may also contribute to worsening outcome in COVID-19 and appears to be linked with severe illness and death. Both platelets and endothelial cells work closely to keep blood flowing smoothly and normally. These are both disrupted in COVID-19 along with inflammation and coagulopathy.

The team also presents the mechanisms that might account for the contribution of cardiovascular risk factors to the most severe outcomes in COVID-19. Patients with risk factors such as diabetes mellitus, aging, and obesity already have underlying platelet and endothelial dysfunction, and when exacerbated by SARS-CoV2 can lead to catastrophic clotting and increased risk of death.

“With an understanding of the many forces that combine to promote clotting in COVID-19 we can better manage the current and future coronavirus pandemics,” said senior author Hwa.

Addressing the excessive clot formation and severe endothelial illness may provide additional therapeutic strategies that would benefit high-risk patients. Several FDA-approved medications that target these cells are currently under investigation for use against COVID-19. The authors concluded that a combination of therapies could also be more successful.

Other authors are Kanika Jain, Vivian Gu, Seung Hee Lee, Jonathan M. Hwa, Jennifer M. Kwan, Diane S. Krause, Alfred I. Lee, Stephanie Halene, Kathleen A. Martin and Hyung J. Chun.

Provided by Yale University

Medicine

Oxford Coronavirus Vaccine Produces Strong Immune Response in Older Adults (Medicine)

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The ChAdOx1 nCov-2019 coronavirus vaccine, developed by teams at the University of Oxford, has been shown to trigger a robust immune response in healthy adults aged 56-69 and those over 70 years of age. The data, published today in The Lancet, suggest that one of the groups most vulnerable to serious illness, and death from COVID-19, could build immunity.

©University of Oxford

“Our vaccine work is progressing quickly. To ensure you have the latest information or to find out more about the trial, please visit the Oxford COVID-19 vaccine web hub or visit the COVID-19 trial website“, said Dr Angela Minassian,

Older adults have been shown to be at higher risk from COVID-19 and should be considered to be a priority for immunisation should any effective vaccine be developed for the disease. Reporting on data from a Phase II trial of the ChAdOx1 nCov-2019 vaccine, the authors write that volunteers in the trial demonstrate similar neutralising antibody titres, and T cell responses across all three age groups (18-55, 56-79, and 70+).

During the Phase 2 trial the vaccine has been evaluated in 560 healthy adult volunteers aged between 18-55 years, 56-69 years and aged 70 or over. Volunteers received 2 doses of the vaccine ChAdOx1 nCoV-19, or a placebo MenACWY vaccine. No serious adverse health events related to ChAdOx1 nCoV-19 were seen in these volunteers.

These data are consistent with the Phase I data reported for healthy adults aged 18-55 early this year.

Dr Maheshi Ramasamy, Investigator at the Oxford Vaccine Group and Consultant Physician said:

‘Older adults are a priority group for COVID-19 vaccination, because they are at increased risk of severe disease, but we know that they tend to have poorer vaccine responses.’

‘We were pleased to see that our vaccine was not only well tolerated in older adults; it also stimulated similar immune responses to those seen in younger volunteers. The next step will be to see if this translates into protection from the disease itself.’

For most vaccines, older adults do not exhibit as strong a response as younger adults, and vaccine-induced antibodies commonly display a lower protective capacity. The data reported today are particularly promising, as they show that the older individuals in this study, who are more prone to serious illness and death from COVID-19, are showing a similar immune response to younger adults.

Dr Angela Minassian, Investigator at the University of Oxford and Honorary Consultant in Infectious Diseases said:

‘Inducing robust immune responses in older adults has been a long-standing challenge in human vaccine research.’

‘To show this vaccine technology is able to induce these responses, in the age group most at risk from severe COVID-19 disease, offers hope that vaccine efficacy will be similar in younger and older adults’.

Furthermore, the vaccine was less likely to cause local reactions at the injection site and symptoms on the day of vaccination in older adults than in the younger group., demonstrating that assessment of the efficacy of the vaccine is warranted in all age groups.

The Phase III trials of the ChAdOx1 nCov-2019 vaccine are ongoing, with early efficacy readings possible in the coming weeks.

Provided by University of Oxford

Chemistry

Self-constructed Macrocycles With Low Symmetry (Chemistry)

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The synthesis and self-organization of biological macromolecules is essential for life on earth. LMU chemists now report the spontaneous emergence of complex ring-shaped macromolecules with low degrees of symmetry in the laboratory.

Two views of the main chain of the crystal structure of a perfectly unimolecular 23mer that spontaneously forms from a single monomer. Source: Huc Group

Molecules that are made up of multiple repeating subunits, known as monomers, which may vary or not in their chemical structure, are classified as macromolecules or polymers. Examples exist in nature, including proteins and nucleic acids, which are at the heart of all biological systems. Proteins not only form the basis of structural elements in cells, they also serve as enzymes – which catalyze essentially all of the myriad of chemical transformations that take place in living systems. In contrast, nucleic acids such as DNA and RNA serve as informational macromolecules. DNA stores the cell’s genetic information, which is selectively copied into RNA molecules that provide the blueprints for the synthesis of proteins. In addition, long chains comprised of sugar units provide energy reserves in the form of glycogen, which is stored in the liver and the muscles. These diverse classes of polymeric molecules all have one feature in common: They spontaneously fold into characteristic spatial conformations, for example the famous DNA double helix, which in most cases are essential for their biochemical functions.

Professor Ivan Huc (Department of Pharmacy, LMU) studies aspects of the self-organization processes that enable macromolecules to adopt defined folded shapes. The molecular structures found in nature provide him with models, whose properties he tries to reproduce in the laboratory with non-natural molecules that are neither proteins, nucleic acids or sugar-like. More specifically, he uses the tools of synthetic chemistry to elucidate the underlying principles of self-organization – by constructing molecules that are expressly designed to fold into predetermined shapes. Beginning with monomers that his group has developed, he sets out to produce what he calls ‘foldamers’, by assembling the monomers one by one to generate a folded macromolecule.

Pappas et al.

Structures with low degrees of symmetry

“The normal way to get the complex structure of proteins is to use different types of monomers, called amino acids”, as Huc reports. “And the normal method to connect different amino acids in the the correct order is to link them one by one.” The sequence of amino acids contains the folding information that allows different protein sequences to fold in different ways.

“But we discovered something unexpected and spectacular”, comments Huc. He and his colleagues in Munich, Groningen, Bordeaux and Berlin used organic, sulfur-containing monomers to spontaneously get cyclic macromolecules with a complex shape, as illustrated by their low degree of symmetry, without requiring a specific sequence. The macromolecules self-synthesize – no further conditions are necessary. “We only put one monomer type in a flask and wait”, Huc says. “This is typical for a polymerization reaction, but polymers from a single monomer usually don´t adopt complex shapes and don’t stop growing at a precise chain length.”

To further control the reaction, the scientists also used either a small guest molecule or a metal ion. The regulator binds within the growing macromolecule and causes monomers to arrange themselves around it. By choosing a regulator with the appropriate characteristics, the authors of the new study were able to produce structures with a predetermined number of subunits. The cyclic macromolecules exhibited low levels of symmetry. Some consisted of either 13, 17 or 23 subunits. Since 13, 17 and 23 are prime numbers, the corresponding folded shapes exhibit low degrees of symmetry.

A model for biological and industrial processes

Interest in the elucidation of such mechanisms is not restricted to the realm of basic research. Huc and his colleagues hope that their approach will lead to the fabrication of designer plastics. Conventional polymers usually consist of mixtures of molecules that vary in length (i.e. the number of monomers they contain). This heterogeneity has an impact on their physical properties. Hence, the ability to synthesize polymer chains of an exact length and/or geometry is expected to lead to materials with novel and interesting behaviors.

Furthermore, foldamers like those that have now been synthesized show close structural resemblances to biopolymers. They therefore offer an ideal model system in which to study the properties of proteins. Every protein is made up of a defined linear (i.e. unbranched) sequence of amino acids, which constitutes its ‘primary structure’. But most amino-acid chains fold into local substructures such as helically coiled stretches, or parallel strands that can form sheets. These units represent the protein’s secondary structure. The term ‘tertiary structure’ is applied to the fully folded single chain. This in turn can interact with other chains to form a functional unit or quaternary structure.

Huc‘s ultimate goal is to mimic complex biological mechanisms using structurally defined, synthetic precursors. He wants to understand how, for example, enzymes fold into the correct, biologically active conformation following their synthesis in cells. Molecules whose properties can be precisely controlled in the laboratory provide ideal models with which to work out the answers and perhaps to go beyond enzymes themselves.

References: Pappas, C.G., Mandal, P.K., Liu, B. et al. Emergence of low-symmetry foldamers from single monomers. Nat. Chem. 12, 1180–1186 (2020). https://www.nature.com/articles/s41557-020-00565-2 https://doi.org/10.1038/s41557-020-00565-2

Provided by LMU Munich

Paleontology

Rapid Climate Change Around 180 Million Years Ago Spread Well-known Long-necked Dinosaurs (Paleontology)

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Global warming triggered the evolution of giant dinosaurs. An international team of paleontologists, including LMU Professor Oliver Rauhut, finds evidence of rapid climate change 180 million years ago as the cause of the spread of the well-known long-necked dinosaurs.

Live reconstruction of the early sauropod Bagualia alba. Illustration: Jorge Gonzales

When we hear the word dinosaur, most of us probably immediately think of giant animals with massive bodies, long necks and tails, and tiny heads. These „quintessential dinosaurs“ actually represent one prominent subgroup of the Dinosauria, the so called Sauropoda (‚long-necked dinosaurs‘ in popular culture). Sauropods were truly amazing animals, and included the largest land-living animals known, with body lengths of up to 40 m and weights of 70 tons or more.

However, these giant animals did not appear directly at the beginning of the era of dinosaurs. For the first fifty million years of their evolutionary history, the Sauropodomorpha – the lineage that the sauropods belong to – were represented by several groups of bipedal to quadrupedal animals. Although some of them reached already large body sizes of about ten meters in length and a few tons in weight, these groups also included smaller, and lightly built animals, some of which not larger than a goat. Furthermore, all of these animals had rather slender teeth, indicating that these plant-eating animals fed on rather soft and lush vegetation. However, towards the end of the Early Jurassic period, some 180 million years ago, all these groups suddenly disappear, and only one lineage survived and thrived – the sauropods. What caused this faunal change during the Early Jurassic has remained enigmatic so far.

An international team of researchers, led by Argentinean paleontologist Diego Pol and including Munich researcher Oliver Rauhut of the Ludwig-Maximilians-University and the Bayerische Staatssammlung für Paläontologie und Geologie, now report new evidence on what might have caused these changes. In the province of Chubut, Argentinean Patagonia, they did not only discover the fossil remains of one of the oldest large sauropods known, which the team named Bagualia alba, but could also place it very precisely in its temporal and ecological context. Thus, the layers the new sauropod comes from could very precisely be dated as 179 million years ago, just after the mysterious disappearance of the other sauropodomorph groups, and finds of plant fossils in rock layers just before that time and at the time that Bagualia alba lived provide evidence for the climate and the ecology that these animals lived in.

Thus, the data indicate that there was a relative rapid change in climate about 180 million years ago, from a temperate warm and humid climate, in which a diverse, lush vegetation flourished, to a strongly seasonal, very hot and dry climate, characterized by a less diverse flora, dominated by forms showing adaptations for hot climates, such as certain conifers. These environmental changes were apparently driven by a greenhouse effect due to climate gasses such as CO2 and methane caused by increased volcanism at that time; evidence of these volcanic eruptions are found on many southern continents, such as the Drakensberge in southern Africa.

With their slender teeth, the non-sauropodan sauropodomorphs were adapted to the rather soft vegetation flourishing before this global warming event, but when this flora was replaced by the much tougher greenhouse vegetation, these animals died out. The sauropods represented the only group of sauropodomorphs with a much more robust dentition, well-adapted for such tough vegetation, and thus they flourished and became the dominant group of herbivorous dinosaurs at that time. Indeed the specialization for this kind of vegetation was probably one of the reasons why these animals reached their gigantic sizes: As large digestion chambers are needed to cope with such food, there was a general tendency for these animals to become ever larger.

References: D. Pol , J. Ramezani , K. Gomez , J. L. Carballido , A. Paulina Carabajal , O. W. M. Rauhut , I. H. Escapa and N. R. Cúneo, “Extinction of herbivorous dinosaurs linked to Early Jurassic global warming event”, Proceedings of Royal Society B, 2020. https://royalsocietypublishing.org/doi/10.1098/rspb.2020.2310# https://doi.org/10.1098/rspb.2020.2310

Provided by LMU Munich

Biology

Obesity, Age and BAME Ethnicity Associated With Higher COVID-19 Antibody Levels (Biology)

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Researchers studying a group of UK healthcare workers discovered that non-white individuals recovering from COVID-19 displayed higher antibody levels than white individuals, with significantly greater levels observed in Asian individuals.

Viral antibodies

Led by experts at the University of Birmingham, the researchers studied a cohort of 956 UK healthcare workers who self-isolated between March and June 2020 because of COVID-19.

Within this group, the researchers identified 442 (46.2%) individuals with SARS-CoV-2 antibodies using a sensitive combined IgG,A,M antibody test developed in collaboration with The Binding Site and also individual antibody tests.

They also discovered that increasing age was associated with a higher IgG response, with antibodies in individuals aged 56-65 significantly higher than those aged 26-35.

Researchers from the Universities of Birmingham, Oxford and Southampton also noted a strong association between obesity and IgG response which increased in proportion to Body Mass Index (BMI). The group’s findings are published on the pre-print server medRxiv and have not yet been peer reviewed.

Study lead Professor Alex Richter, Honorary Consultant in Clinical Immunology at the University of Birmingham, commented: “We were surprised to find that risk factors associated with severe COVID-19 were also associated with higher antibody levels in convalescent health care workers after mild disease. We need to understand this observation and the role of antibodies in COVID-19 as this has implications for vaccination and convalescent plasma as a treatment.”

The study also revealed that a considerable number of working days were lost to staff members isolating for symptoms that were not proven to be COVID-19, highlighting the importance of testing. The combination of cough, fever or loss of smell captured 92.3% of individuals who tested positive for COVID-19 – validating these symptoms as an effective way of determining who should self-isolate.

The research team also discovered that most COVID-19 antibody positive hospital workers suffered their illness prior to patients being admitted to hospital in large numbers, highlighting the importance of both community and hospital transmission of the virus.

“Our combined IgG,A,M SARS-CoV-2 antibody test offers greater sensitivity than individual IgG antibody tests and helps identify more people who have previously been exposed to the virus and the risk factors associated with this” added lead author Dr Adrian Shields.

References: Adrian M Shields, Sian E Faustini, Marisol Perez-Toledo, Sian Jossi, Joel D Allen,+, Saly Al-Taei, Claire Backhouse, Lynsey Dunbar, Daniel Ebanks, Beena Emmanuel, Aduragbemi A Faniyi, Mark I. Garvey, Annabel Grinbergs, Golaleh McGinnell, Joanne O’Neill, Yasunori Watanabe, Max Crispin, David. C Wraith, Adam F Cunningham, Mark T Drayson, Alex G Richter, ‘Serological responses to SARS-CoV-2 following non-hospitalised infection: clinical and ethnodemographic features associated with the magnitude of the antibody response’, MedRXiv, 2020. doi: https://doi.org/10.1101/2020.11.12.20230763 https://www.medrxiv.org/content/10.1101/2020.11.12.20230763v1.full

Provided by University of Birmingham

Chemistry, Quantum Mechanics

Enhancing Battery Performance With Quantum Sensors (Chemistry)

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A new project aimed at harnessing quantum technology to enhance vehicle battery performance has been awarded Partnership Resource Funding by the University of Birmingham-led UK Quantum Technology Hub Sensors and Timing.

©University of Brimingham

The project, led by University of Sussex researchers, addresses a crucial need to increase battery energy density, longevity and safety. It will mark the first time quantum sensors are used as a solution in battery innovation.

Improving vehicle battery technology is key in delivering the Government’s 10-point plan for a Green Industrial Revolution, which confirms the UK will end the sale of new petrol and diesel cars by 2030. In order to meet these and other national and international decarbonisation targets, substantial research and development in these areas is urgently needed.

The project, which also includes the Universities of Strathclyde and Edinburgh as part of the consortium, aims to do exactly this by translating existing highly sensitive world-leading quantum magnetometer technology to an industrial-grade imaging device, to accurately examine the battery’s microscopic current flows. This technology will facilitate rapid assessments of new and existing battery chemistries to accelerate the creation of superior battery technology.

As with all the technology in development at the UK Quantum Technology Hub Sensors and Timing, which partners with the Universities of Sussex, Strathclyde, Glasgow, Southampton, Nottingham, Imperial College London, NPL and the British Geological Survey, the aim is to develop small, low power, portable devices that require no infrastructure and minimal running costs, suitable for economical production.

The increased battery energy and power density can also be exploited to continue the electrification transport, such as moving to electric aircrafts.

Academics will also work closely with CDO2, Magnetic Shields Ltd and QinetiQ to work towards their goal of developing a viable sensor prototype ready for handover to industry for commercial exploitation. In particular, Magnetic Shields Ltd will provide the required magnetic noise-free environment to allow the sensor technology to be tested with unprecedented sensitivity.

Professor Peter Kruger, Research Professor of Experimental Physics at the University of Sussex, said: “We hope, through this project, to initiate an increase in the creation of new battery technologies through a better understanding of battery performance.”

“By facilitating improvements in battery energy density, manufacturing costs, battery lifetime and safety we hope to reduce carbon emissions and waste production globally.”

David Woolger, Director at Magnetic Shields Ltd, said: “We are delighted to be providing the necessary equipment and facilities to help develop this imaging technology, and look forward to the next steps towards commercial exploitation.”

Innovation in magnetometer devices will also bring synergistic benefits in other part of the Quantum Technology Hub, such as biomedical imaging.

Provided by University of Birmingham