Despite 300 years of research, and a recent renaissance in the study of their biological make-up, the mysterious, marauding teleosauroids have remained enduringly elusive.

Scientific understanding of this distant cousin of present day long snouted gharials has been hampered by a poor grasp of their evolutionary journey — until now.

Researchers from the University of Edinburgh have identified one previously unknown species of teleosauroid and seven of its close relatives — part of a group that dominated Jurassic coastlines 190 to 120 million years ago.

Their analysis offers tantalising glimpses of how teleosauroids adapted to the momentous changes that occurred during the Jurassic period, as the earth’s seas experienced many changes in temperature.

“Our study just scratches the surface of teleosauroid evolution,” says study lead Dr Michela M. Johnson, of the University’s School of GeoSciences. “But the findings are remarkable, raising interesting questions about their behaviour and adaptability.

“These creatures represented some of the most successful prehistoric crocodylomorphs during the Jurassic period and there is so much more to learn about them.”

The study reveals that not all teleosauroids were engaged in cut and thrust lifestyles, snapping at other reptiles and fish from the seas and swamps near the coast.

Instead, they were a complex, diverse group that were able to exploit different habitats and seek out a variety of food sources. Their physical make-up is also more diverse than was previously understood, the scientists say.

Previous research had provided insights into the origins and evolution of this fossilised croc’s whale-like relatives metriorhynchids, but less was known about teleosauroids.

To address this, the expert team of palaeontologists examined more than 500 fossils from more than 25 institutions around the world.

Cutting edge computer software enabled the team to glean swathes of revealing data regarding their anatomical similarities and differences, by examining the entire skeleton, teeth and bony armor, which indicated whether species were closely related or not.

This information enabled the team to create an up-to-date family tree of the teleosauroids group from which emerged two new large groups, whose anatomy, abundance, habitat, geography and feeding styles differ from one another significantly.

The first group, teleosaurids, were more flexible in terms of their habitat and feeding. The second group known as machimosaurids — which included the fearsome turtle crushers, Lemmysuchus and Machimosaurus — were more abundant and widespread.

Names given by the team to seven newly described fossils, found in both teleosaurids and machimosaurids, reflect a curious range of anatomical features — among them Proexochokefalos, meaning ‘large head with big tuberosities’ and Plagiophthalmosuchus, the ‘side-eyed crocodile’.

There are even hints of their diverse behavioural characteristics and unique locations — Charitomenosuchus, meaning ‘graceful crocodile’ and Andrianavoay, the ‘noble crocodile’ from Madagascar.

Researchers have named the newly discovered species, Indosinosuchus kalasinensis, after the Kalasin Province in Thailand, where the fossil — now housed in Maha Sarakham University — was found.

The recognition of I. kalasinensis shows that at least two species were living in similar freshwater habitats during the Late Jurassic — an impressive feat as teleosauroids, with the exception of Machimosaurus, were becoming rare during this time.

Dr Steve Brusatte, Reader in Vertebrate Palaentology, at the School of Geosciences, University of Edinburgh, said: “The same way family trees of our own ancestors and cousins tell us about our history, this huge new family tree of teleosauroids clarifies their evolution. They were some of the most diverse and important animals in the Jurassic oceans, and would have been familiar sights along the coastlines for tens of millions of years.”

The study, published in the scientific journal PeerJ, was funded by the Natural Sciences and Engineering Council of Canada, SYNTHESYS Project and Leverhulme Trust Research. The Palaeontological Association and Paleontological Society provided travel grants.

It’s an important long-term question for policymakers seeking to increase renewable electricity production, cost-effectiveness and efficiency with limited budgets, says C.-Y. Cynthia Lin Lawell, associate professor in the Charles H. Dyson School of Applied Economics and Management at Cornell University.

In a new study focused on Denmark, a global leader in wind energy — a relatively mature and low-cost renewable technology — Lin Lawell found that government policies have been the primary driver of that industry’s growth and development.

“Technological progress alone wouldn’t have led to that widespread development of wind energy in Denmark,” said Lin Lawell, the Robert Dyson Sesquicentennial Chair in Environmental, Energy and Resource Economics. “Well-designed policy may be an important contributor for nascent industries like renewables, which need to develop technology and which have broader societal benefits in terms of the environment.”

Lin Lawell is the co-author with Jonathan Cook, an associate in her DEEP-GREEN-RADAR research group, of “Wind Turbine Shutdowns and Upgrades in Denmark: Timing Decisions and the Impact of Government Policy,” published in a recent issue of The Energy Journal.

Wind turbines in many countries are approaching the end of their useful lives of roughly 20 years, Cook and Lin Lawell note, making decisions about whether to scrap or upgrade them increasingly relevant.

Denmark is ahead of that curve, having promoted wind energy since the oil crisis in the late 1970s. The country produces over 40% of its electricity from wind power and dominates other countries, the authors said, in wind deployment per capita and per gross domestic product. The Danish wind industry is highly decentralized, with 88% of the nearly 3,000 producers included in the 32-year study period from 1980-2011 operating no more than two turbines.

The researchers built a dynamic structural econometric model that incorporated the capacity, age and location of every turbine operated by small producers during that period. The model’s “bottom-up” approach enabled analysis of individual owners’ decisions to shut down, upgrade or add turbines over time, and simulated outcomes if government policies had been scaled back or were not implemented.

“Understanding the factors that influence individual decisions to invest in wind energy and how different policies can affect the timing of these decisions is important for policies both in countries that already have mature wind industries,” the researchers wrote, “as well as in regions of the world that are earlier in the process of increasing renewable electricity generation (e.g. most of the U.S.).”

Denmark since the late 1970s has offered a feed-in tariff that guaranteed producers a fixed price per amount of wind energy generated, whether turbines were new or old. Since 1999, replacement certificates have incentivized upgrades.

Both policies significantly impacted small producers’ shutdown and upgrade decisions and accelerated the development of Denmark’s wind industry, the scholars concluded. Without them, the model showed most small-scale wind producers would have left the industry by 2011, concentrating production in larger wind farms.

However, the analysis determined that replacement certificates were far more cost-effective than the feed-in tariff in encouraging small producers to add or upgrade turbines, helping Denmark reduce its carbon emissions.

The study estimated the Danish government spent $3.5 billion on the feed-in tariff program over the study period, and as much as $114 million on the replacement certificates. Together, the two programs reduced carbon emissions by 57.4 million metric tons of carbon dioxide.

“One was just really expensive at doing it,” Lin Lawell said. “Both the cost per metric ton of carbon dioxide avoided, and the cost per percentage point increase in payoff to the turbine owner, are much lower for the replacement certificate program.”

For every million metric tons of carbon dioxide avoided, the researchers estimated the feed-in tariff cost Danish taxpayers $61.8 million, compared to $2.2 million or less for the replacement certificates.

Cook and Lin Lawell said their analysis offers lessons about the role of government policy in incentivizing the development of renewables and about which policies generate the most bang for the buck.

“Our application to the Danish wind industry,” they wrote, “has important implications for the design of renewable energy policies worldwide.”

Physicists began using supercomputers to obtain solutions to this famously hard problem back in the 1960s. In 2000, with no solutions in sight, Kip Thorne, 2018 Nobel Laureate and one of the designers of LIGO, famously bet that there would be an observation of gravitational waves before a numerical solution was reached.

He lost that bet when, in 2005, Carlos Lousto, then at The University of Texas at Brownsville, and his team generated a solution using the Lonestar supercomputer at the Texas Advanced Computing Center. (Concurrently, groups at NASA and Caltech derived independent solutions.)

In 2015, when the Laser Interferometer Gravitational-Wave Observatory (LIGO) first observed such waves, Lousto was in shock.

“It took us two weeks to realize this was really from nature and not from inputting our simulation as a test,” said Lousto, now a professor of mathematics at Rochester Institute of Technology (RIT). “The comparison with our simulations was so obvious. You could see with your bare eyes that it was the merger of two black holes.”

Lousto is back again with a new numerical relativity milestone, this time simulating merging black holes where the ratio of the mass of the larger black hole to the smaller one is 128 to 1 — a scientific problem at the very limit of what is computational possible. His secret weapon: the Frontera supercomputer at TACC, the eighth most powerful supercomputer in the world and the fastest at any university.

His research with collaborator James Healy, supported by the National Science Foundation (NSF), was published in Physical Review Letters this week. It may require decades to confirm the results experimentally, but nonetheless it serves as a computational achievement that will help drive the field of astrophysics forward.

“Modeling pairs of black holes with very different masses is very computational demanding because of the need to maintain accuracy in a wide range of grid resolutions,” said Pedro Marronetti, program director for gravitational physics at NSF. “The RIT group has performed the world’s most advanced simulations in this area, and each of them takes us closer to understanding observations that gravitational-wave detectors will provide in the near future.”

LIGO is only able to detect gravitational waves caused by small and intermediate mass black holes of roughly equal size. It will take observatories 100 times more sensitive to detect the type of mergers Lousto and Healy have modeled. Their findings show not only what the gravitational waves caused by a 128:1 merger would look like to an observer on Earth, but also characteristics of the ultimate merged black hole including its final mass, spin, and recoil velocity. These led to some surprises.

“These merged black holes can have speeds much larger than previously known,” Lousto said. “They can travel at 5,000 kilometers per second. They kick out from a galaxy and wander around the universe. That’s another interesting prediction.”

The researchers also computed the gravitational waveforms — the signal that would be perceived near Earth — for such mergers, including their peak frequency, amplitude, and luminosity. Comparing those values with predictions from existing scientific models, their simulations were within 2 percent of the expected results.

Previously, the largest mass ratio that had ever been solved with high-precision was 16 to 1 — eight times less extreme than Lousto’s simulation. The challenge of simulating larger mass ratios is that it requires resolving the dynamics of the interacting systems at additional scales.

Like computer models in many fields, Lousto uses a method called adaptive mesh refinement to get precise models of the dynamics of the interacting black holes. It involves putting the black holes, the space between them, and the distant observer (us) on a grid or mesh, and refining the areas of the mesh with greater detail where it is needed.

Lousto’s team approached the problem with a methodology that he compares to Zeno’s first paradox. By halving and halving the mass ratio while adding internal grid refinement levels, they were able to go from 32:1 black hole mass ratios to 128:1 binary systems that undergo 13 orbits before merger. On Frontera, it required seven months of constant computation.

“Frontera was the perfect tool for the job,” Lousto said. “Our problem requires high performance processors, communication, and memory, and Frontera has all three.”

The simulation isn’t the end of the road. Black holes can have a variety of spins and configurations, which impact the amplitude and frequency of the gravitational waves their merger produces. Lousto would like to solve the equations 11 more times to get a good first range of possible “templates” to compare with future detections.

The results will help the designers of future Earth- and space-based gravitational wave detectors plan their instruments. These include advanced, third generation ground based gravitational wave detectors and the Laser Interferometer Space Antenna (LISA), which is targeted for launch in the mid-2030s.

The research may also help answer fundamental mysteries about black holes, such as how some can grow so big — millions of times the mass of the Sun.

“Supercomputers help us answer these questions,” Lousto said. “And the problems inspire new research and pass the torch to the next generation of students.”

The study was published in the journal Acta Palaeontologica Polonica.

In order to study the appearance of dinosaurs more closely, researchers today rely on a large number of skeletons in so-called bone beds, which are places where the animals sank into the mud in large numbers during their lifetime. However, juvenile animals had hardly been found in these until now. Researchers described fossils of still juvenile plateosaurs for the first time just a few years ago, but these were already almost as large as the adults. One possible reason: “The smaller individuals probably did not sink into the mud quite as easily and are therefore underrepresented at the bone beds,” suspects study leader Prof. Martin Sander of the University of Bonn.

He and his team used comparative anatomy to examine the new skeleton, which was immediately remarkable because of its small size. “Based on the length of the vertebrae, we estimate the total length of the individual to be about 7.5 feet (2.3 meters), with a weight of about 90 to 130 lbs. (40 to 60 kilograms),” explains Darius Nau, who was allowed to examine the find for his bachelor’s thesis. For comparison: Adult Plateosaurus specimens reached body lengths of 16 to 33 feet (five to ten meters) and could weigh more than four tons. Because of its small size alone, it was obvious to assume that “Fabian” was a juvenile animal. This assumption was confirmed by the fact that the bone sutures of the spinal column had not yet closed. Background: Similar to skull sutures in human babies, bone sutures only fuse over the course of life.

Young and old resembled each other anatomically and in their body proportions

Researchers found that the young dinosaur resembled its older relatives both in anatomical details, such as the pattern of the laminae on the vertebrae (bony lamellae connecting parts of the vertebrae, which are important anatomical features in many dinosaurs), and in the rough proportions of its body. “The hands and neck of the juveniles may be a little longer, the arm bones a little shorter and slimmer. But overall, the variations are relatively small compared to the variation within the species overall and also compared to other dinosaur species,” stresses Nau. The juveniles of the related Mussaurus for instance were still quadrupeds after hatching, but the adults were bipeds.

“The fact that the Plateosaurus juvenile already looked so similar to the adults is all the more remarkable considering that they were ten times heavier,” emphasizes paleontologist Dr. Jens Lallensack from the University of Bonn. It is however conceivable that the morphological development differed greatly from animal to animal, depending on the climatic conditions or the availability of food. Such differences are still seen in reptiles today.

The well-known descendants of Plateosaurus, the sauropods, are the subject of a current exhibition at the Zoological Research Museum Alexander Koenig in Bonn. The largest Plateosaurus skeleton ever found can be seen there.

Funding

The study received financial support for the excavation and preparation of the skeleton from the municipality of Frick and the Canton of Argonia (Swisslos-Fonds) of Switzerland.

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Down syndrome, the most common congenital disease in human genetics, has seen dramatic increases in longevity with advances in modern medicine. Unfortunately, new problems associated with this increased longevity have emerged, such early Alzheimer’s, reduced vision, and muscle weakness. However, unlike the nervous system, the vascular system in Down syndrome patients is very resistant to aging pathologies like solid cancers (as opposed to blood cancers such as leukemia), atherosclerosis, hypertension, and Kawasaki disease — a systemic vasculitis that some researchers say has a connection to SARS-CoV-2, the virus that causes COVID-19. It has therefore become important to conduct comprehensive genomic and pathological analyses, including secondary analyses of gene expression on Down syndrome chromosomes and changes due to different chromosome numbers, to determine its cause.

Down syndrome occurs when there is an extra chromosome 21 instead of the usual two. DSCR-1 is located on chromosome 21 and suppresses signals related to angiogenesis. A research group based in Kumamoto University (Japan) crossed hypercholesterolemia (ApoE-deficient) mice with those that highly expressed DSCR-1 and those that were DSCR-1-deficient to analyze the effects of aging. By examining the pathological signals produced by high cholesterol, they hoped to determine why corneal opacity (prominent in ApoE deficiency) is protected against by high DSCR-1 expression and exacerbated by DSCR-1 deficiency.

DSCR-1-deficient mice showed slight age-related corneal opacity, which was dramatically exacerbated when crossed with ApoE-deficient mice, and increased corneal inflammation. DSCR-1 protects postnatal homeostasis based on its inhibitory and antioxidant effects on the NFAT transcription factor — a major factor in the development of Down syndrome. DSCR-1 deficiency results in the abnormal activation of NFAT and the signal transduction function of SDF-1 and its receptor CXCR4, which has an angiogenic effect in peripheral blood vessels. This results in increased angiogenesis and lymphangiogenesis in the corneal area.

Researchers further clarified that DSCR-1 deficiency increases oxidized LDL cholesterol which, in turn, increases SDF-1 production in the endothelium and the production of the angiogenesis-promoting factor VEGF in infiltrating macrophages, thus resulting in pathological angiogenesis (and clouding) in the cornea. This condition was greatly alleviated by the administration of antibodies that neutralize the function of SDF-1.

“This study shows that, in addition to suppressing cancer growth and cytokine storms in sepsis, DSCR-1 may have a protective effect on pathological angiogenesis under high cholesterol conditions,” said study leader, Professor Takashi Minami. “We have also obtained data on NFAT/DSCR-1 signaling in patients with human corneal lesions, suggesting that drugs that block NFAT and its downstream SDF-1 function may be effective in protecting against age-related vascular disease.”

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The findings have been published in PNAS today and are important to efforts to develop broad-spectrum antiviral agents.

Professor Spencer Williams from the School of Chemistry at Bio21 said the research will help define a new ‘host-directed’ approach for treating infections by encapsulated viruses.

“One approach to treating viral infections is to make a new drug for each virus that comes along. But it is slow. An alternative and attractive approach is to make a drug against a human target that viruses need to replicate. The same drug can then be used and reused against many different viruses, even ones that have yet to emerge,” he said.

The findings result from work by Professor Gideon Davies and his UK team who clarified how the structure of the catalytic domain of human enzyme that trims sugar molecules from proteins during their production and Professor Williams’ and his Bio21 team, who developed a series of inhibitors to block the enzyme.

When tested in human cell lines, these inhibitors where shown to reduce infection in dengue viruses.

“Encapsulated viruses tend to harness the ‘glycosylation’ step of protein production, whereby glycans, or sugar molecules coat newly assembled proteins,” said Professor Williams.

“The sugar molecules provide instructions for proteins to fold into their correct 3D structure as well as transport instructions for the protein to be brought to its next destination within the cell. Glycosylation is facilitated by various enzymes that synthesize, trim, check and modify these sugar molecules.”

Our body’s cells contain around 42 million protein molecules. Protein production is a complex, multi-step process within the cell. Like products on a factory assembly-line, all proteins pass through ‘quality control’ check points where they are inspected before they are transported to their destination, to carry out their functions.

Viruses are not living organisms, but biological programs encoded in ribonucleic acid (RNA) or deoxyribonucleic acid (DNA).

They come to life when they enter a living cell and hijack the protein production systems. Viruses use the cell’s machinery to copy their DNA or RNA (in the case of SARS-CoV2, it’s RNA) and to produce the proteins they need to make copies of themselves.

The viral proteins produced in an infected cell undergo the ‘glycosylation’ and then pass through the quality control steps, which involves ‘trimming’ by an enzyme called ‘MANEA’.

“Trimming is a crucial quality control step and when it does not occur, client proteins are marked for degradation. MANEA represents a key target for broad spectrum drug development against encapsulated viruses, as inhibitors will trigger destruction of their proteins,” said Professor Davies.

Because viruses hijack this unusual biosynthetic pathway, it makes it a good potential drug target.

Researchers at the University of Warwick and University of Oxford studied the effect of the best inhibitors on viral replication.

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