. Scientific Frontline

Thursday, June 30, 2022

Wildfires May Have Sparked Ecosystem Collapse During Earth’s Worst Mass Extinction

Credit: Victor O. Leshyk During the worst mass extinction event in Earth’s history, vast wetlands suffered increased wildfires, turning the world’s largest carbon sinks into carbon sources.
Resized Image using AI by SFLORG
Credit: Victor O. Leshyk 

Researchers at University College Cork (UCC) and the Swedish Museum of Natural History examined the end-Permian mass extinction (252 million years ago) that eliminated almost every species on Earth, with entire ecosystems collapsing. The researchers discovered a sharp spike in wildfire activity from this most devastating of mass extinctions. Promoted by rapid greenhouse gas emissions from volcanoes, extreme warming and drying led to wildfires across vast regions that were previously permanently wet. Instead of capturing carbon from the atmosphere, these wetlands became major sources of atmospheric carbon, enhancing the sharp warming trend. The research is published in PALAIOS today (30th June).

Fossils examined in eastern Australia & Antarctica

By studying fossil plant and charcoal records of the Sydney & Bowen basins in eastern Australia and Antarctica (Lambert Graben), the researchers discovered that the wetlands were regularly disturbed by fires leading up to the extinction event. In response, the plants had evolved a range of fire-coping mechanisms. However, the severe climate change and peak in fire activity during the extinction event seems to have pushed even these fire-adapted plants over a tipping point, from which the entire ecosystem could not recover for millions of years.

“Sifting through the fossil plant records of eastern Australia and Antarctica, we found high abundances of burnt, or charcoalified, plants throughout the late Permian Period. From this high baseline, charcoal abundances reached a prominent peak right at the top of the last Permian coal beds, indicating a major but short-lived increase in wildfires. This was followed by low charcoal for the next three million years of the Early Triassic Period. It was an end-Permian burnout, followed by an Early Triassic depression” comments Dr Chris Mays, Lecturer in Paleontology at University College Cork (UCC) and lead author of the study.

Earth on a path to a similar mass extinction?

The researchers highlight that in today’s world, wildfires have caused shocking mass animal die-offs in several regions around the world (e.g. California 2018, 2020, Australia 2019-20). Over the same time, our warming global climate has led to prolonged droughts and increased wildfires in typically wet habitats, such as the peat forests of Indonesia and the vast Pantanal wetlands of South America. These major ‘carbon sinks’―regions of natural capture of carbon from the atmosphere―are crucial in our fight against climate change. As the fossil record reveals, without these regions of carbon capture, the world can stay intolerably warm for hundreds of millennia.

“The potential for wildfires as a direct extinction driver during hyperthermal events, rather than a symptom of climatic changes deserves further examination. Unlike the species that suffered the mass extinctions of the past, we have the opportunity to prevent the burning of the world’s carbon sinks and help avoid the worst effects of modern warming” comments Dr Mays.

Source/Credit: Coláiste na hOllscoile Corcaigh (University College Cork)

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Scientists find trigger that sets off metastasis in pancreatic cancer

Scientists have found that cancers in the pancreas (left) readily metastasize because these tumors suppress levels of an enzyme, MSRA, that pulls oxygen atoms off amino acids called methionine. As MSRA levels decrease, methionines on proteins become more oxidized. This causes one particular protein to rev up energy production in the tumor, promoting the migration of cancer cells to other organs. Metastatic tumors on the liver (right) lead to rapid death.
Image courtesy of Christopher Chang, UC Berkeley, and Christine Chio, Columbia

Pancreatic cancer, though rare, is one of the deadliest of cancers, killing nearly 50,000 people yearly and doing so quickly, primarily because it metastasizes rapidly through the body. Barely one in 10 people survive beyond five years.

But a discovery by chemists at the University of California, Berkeley, suggests a new way to slow or stop metastatic spread of pancreatic and perhaps other cancers.

In last week’s issue of the journal Molecular Cell, Christopher Chang and his group at UC Berkeley, collaborating with Christine Chio’s team at Columbia University in New York, report that metastasis is triggered by the loss of an enzyme that repairs oxygen damage to proteins.

Without this enzyme to erase the oxidative damage, one particular protein in cancer cells goes on to rev up energy production and seed new cancers around the body. The researchers confirmed this by knocking down levels of the “eraser” enzyme in mice and in cultured mouse and human cells, or organoids. In both cases, this promoted the migration of cancer cells and metastatic spread.

How bacteria adhere to cells: Basis for the development of a new class of antibiotics

Adhesion of Bartonella henselae (blue) to human blood vessel cells (red). The bacterium's adhesion to the host cells could be blocked with the help of what are known as “anti-ligands".
Credit: Goethe University

Researchers from University Hospital Frankfurt and Goethe University Frankfurt have unraveled how bacteria adhere to host cells and thus taken the first step towards developing a new class of antibiotics.

The adhesion of bacteria to host cells is always the first and one of the decisive steps in the development of infectious diseases. The purpose of this adhesion by infectious pathogens is first to colonize the host organism (i.e., the human body), and then to trigger an infection, which in the worst case can end fatally. Precise understanding of the bacteria's adhesion to host cells is a key to finding therapeutic alternatives that block this critical interaction in the earliest possible stage of an infection.

The hawk has landed: braking mid-air to prioritize safety over energy or speed

A Harris hawk braking in mid-air before perching.
Resized image using AI by SFLORG
Credit: Rob Bullingham

New research from the Oxford Flight Group using computer simulations and Hollywood-style motion capture shows how birds optimize their landing maneuvers for an accurate descent.

Researchers at the University of Oxford have found that hawks control their flight to ensure the safest landing conditions when perching, even if it takes longer and more energy to do so. Understanding how birds optimize their landing maneuvers through learning may help in developing small aircraft capable of perching like birds.

In new research published in Nature, four Harris’ hawks wearing tiny retroreflective markers were tracked flying back and forth between two perches. Their precise movements were recorded by 20 motion capture cameras positioned around the room, allowing the research team to reconstruct their flight paths on over 1,500 flights. The research team then used computer simulations to understand why the birds chose their particular path to the perch.

Aircraft have the luxury of using a runway for braking after landing to reduce speed. In contrast, birds must brake before they arrive at the perch – however slowing down to a safe speed while in flight risks stall, leading to a sudden loss of flight control. The researchers discovered that the hawks follow a flight path that slows them down to a safe speed but minimizes the distance from the perch at which they stall.

Wednesday, June 29, 2022

Shrimps and worms among first animals to recover after largest mass extinction

Reconstructed sea bed scenes (A) Pre-extinction, (B-D) Induan (early Early Triassic), (E) Smithian, (F) Spathian
Credit: Yaqi Jiang

Researchers studying ancient sea bed burrows and trails have discovered that bottom burrowing animals were among the first to bounce back after the end-Permian mass extinction.

In a new study, published today in the journal Science Advances, researchers from China, the USA and the UK, reveal how life in the sea recovered from the event, which killed over 90 percent of species on Earth, from their observations of trace fossils.

Life was devastated by the end-Permian mass extinction 252 million years ago, and recovery of life on Earth took millions of years for biodiversity to return to pre-extinction levels. But by examining trails and burrows on the South China sea bed, the international team were able to piece together sea life’s revival by pinpointing what animal activity was happening when.

Professor Michael Benton from the University of Bristol’s School of Earth Sciences, a collaborator on the new paper, said: “The end-Permian mass extinction and the recovery of life in the Early Triassic are very well documented throughout South China.

“We were able to look at trace fossils from 26 sections through the entire series of events, representing seven million crucial years of time, and showing details at 400 sampling points, we finally reconstructed the recovery stages of all animals including benthos, nekton, as well as these soft-bodied burrowing animals in the ocean.”

Falling stardust, wobbly jets explain blinking gamma ray bursts

A close-up view of the disk (in orange) tilting, causing the jets (in purple) to wobble.
Credit: Ore Gottlieb/Northwestern University

A Northwestern University-led team of astrophysicists has developed the first-ever full 3D simulation of an entire evolution of a jet formed by a collapsing star, or a “collapsar.”

Because these jets generate gamma ray bursts (GRBs) — the most energetic and luminous events in the universe since the Big Bang — the simulations have shed light on these peculiar, intense bursts of light. Their new findings include an explanation for the longstanding question of why GRBs are mysteriously punctuated by quiet moments — blinking between powerful emissions and an eerily quiet stillness. The new simulation also shows that GRBs are even rarer than previously thought.

The new study was published today (June 29) in Astrophysical Journal Letters. It marks the first full 3D simulation of the entire evolution of a jet — from its birth near the black hole to its emission after escaping from the collapsing star. The new model also is the highest-ever resolution simulation of a large-scale jet.

“These jets are the most powerful events in the universe,” said Northwestern’s Ore Gottlieb, who led the study. “Previous studies have tried to understand how they work, but those studies were limited by computational power and had to include many assumptions. We were able to model the entire evolution of the jet from the very beginning — from its birth by a black hole — without assuming anything about the jet’s structure. We followed the jet from the black hole all the way to the emission site and found processes that have been overlooked in previous studies.”

New Kangaroo Described from Papua New Guinea

Artist's impression of Nombe Rockshelter Megafauna, showing the Nombe kangaroo on the Right.
Image resized using AI by SFLORG
 Credit: Artwork Courtesy Peter Schouten

Australian paleontologists from Flinders University have described a new genus of giant fossil kangaroo from the mountains of central Papua New Guinea.

The new description of the fossil kangaroo has found that, rather than being closely related to Australian kangaroos, it most likely belongs to a unique genus of more primitive kangaroo found only in PNG.

The kangaroo, first described in 1983 by Professor Tim Flannery, is known from fossils around 20,000-50,000 years old. They come from the Nombe Rockshelter, an archaeological and paleontological site in Chimbu Province, Papua New Guinea.

Nombe is already known for multiple extinct species of kangaroo and giant four-legged marsupials called diprotodontids.

Flinders University researchers have renamed the animal Nombe nombe, after the location of its discovery – and plan to return to PNG for further excavations and research next year.

The squat, muscular Nombe lived in a diverse montane rainforest with thick undergrowth and a closed canopy. Here, it evolved to eat the tough leaves from trees and shrubs, with a thick jaw bone and strong chewing muscles.

Cancer drug shows potential as treatment for muscular dystrophy

Dr. Farshad Babaeijandaghi
Source UBC
Researchers at UBC’s School of Biomedical Engineering have discovered that an existing cancer drug could have potential as a treatment for muscular dystrophy.

The researchers found that the drug — known as a colony-stimulating factor 1 receptor (CSF1R) inhibitor — helped slow the progress of Duchenne muscular dystrophy in mice by increasing the resiliency of muscle fibers.

The findings were published today in Science Translational Medicine.

“This is a class of drug that is already being used in clinical trials to treat rare forms of cancer,” says Dr. Farshad Babaeijandaghi, a postdoctoral fellow at UBC and first author on the study. “To find that it could potentially serve a double purpose as a treatment for muscular dystrophy is incredibly exciting. It shows a lot of promise, and with further testing, could help extend and improve quality of life for patients.”

Duchenne muscular dystrophy (DMD) is a severe genetic disorder that leads to progressive muscle weakness and degeneration due to disruptions to the protein dystrophin, which helps keep muscle cells intact. It is the most common congenital disease in Canada, affecting about one out of every 3,500 males, and in rarer cases, females.

DMD symptoms typically appear in early childhood, with patients facing increased loss of muscle function as they age. As the disease progresses, many patients are forced to rely on mobility aids, such as a wheelchair, with the disease eventually impacting heart and lung function. While improvements in cardiac and respiratory care have increased life expectancy in recent decades, there is currently no cure.

New Organomineral Fertilizers Created in the Urals

A new type of fertilizer was created in the Ural.
Credit: Anastasia Mavrenkova

New organomineral fertilizers have been developed in the Ural. They are based on magnesium, sulfur, silicon, calcium and poultry manure. The manure contains organics (carbon), nitrogen, potassium, and phosphorus. These fertilizers are more effective than organic fertilizers and safer than mineral fertilizers. They can be used for growing plants and for soil regeneration. This is a new kind of fertilizer (analogues consist of peat and other mineral components), registered under the trademark "Organomin". With favorable developments, the production of fertilizers on an industrial scale will begin this year. Now the developer, the company Nika PetroTech, a member of the Ural Interregional Research and Education Center, is in the process of registering a patent, which they expect to receive in the fall.

"Often chicken droppings are used as organic fertilizer by the poultry farms themselves. They grow plants for birds and animals in the fields. However, there are two difficulties. Firstly, often manure is put in excessive amounts - 20-30 tons per hectare, which adversely affects the soil and groundwater. Secondly, since manure contains a large amount of pathogenic microflora, it takes up to six months to decompose. In our case, after adding the mineral component, the manure can be used in a day. Moreover, according to preliminary calculations, our fertilizer is not much needed for productive plant growth - no more than one ton per hectare," explains Sergey Yakovlev, Head of the Engineering and Technological Department of Nika PetroTech.

Physicists confront the neutron lifetime puzzle


To solve a long-standing puzzle about how long a neutron can “live” outside an atomic nucleus, physicists entertained a wild but testable theory positing the existence of a right-handed version of our left-handed universe. They designed a mind-bending experiment at the Department of Energy’s Oak Ridge National Laboratory to try to detect a particle that has been speculated but not spotted. If found, the theorized “mirror neutron” — a dark-matter twin to the neutron — could explain a discrepancy between answers from two types of neutron lifetime experiments and provide the first observation of dark matter.

“Dark matter remains one of the most important and puzzling questions in science — clear evidence we don’t understand all matter in nature,” said ORNL’s Leah Broussard, who led the study published in Physical Review Letters.

Neutrons and protons make up an atom’s nucleus. However, they also can exist outside nuclei. Last year, using the Los Alamos Neutron Science Center, co-author Frank Gonzalez, now at ORNL, led the most precise measurement ever of how long free neutrons live before they decay, or turn into protons, electrons and anti-neutrinos. The answer — 877.8 seconds, give or take 0.3 seconds, or a little under 15 minutes — hinted at a crack in the Standard Model of particle physics. That model describes the behavior of subatomic particles, such as the three quarks that make up a neutron. The flipping of quarks initiates neutron decay into protons.

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