Past climate change to blame for Antarctica’s giant underwater landslides

Dr Jenny Gales (right) and Professor Rob McKay examine the half-section of a core recovered from the Antarctic seabed
Photo Credit: Justin Dodd

Scientists have discovered the cause of giant underwater landslides in Antarctica which they believe could have generated tsunami waves that stretched across the Southern Ocean.

An international team of researchers, led by Dr Jenny Gales from the University of Plymouth, uncovered layers of weak, fossilized and biologically-rich sediments hundreds of meters beneath the seafloor.

These formed beneath extensive areas of underwater landslides, many of which cut more than 100 meters into the seabed.

Writing in Nature Communications, the scientists say these weak layers – made up of historic biological material – made the area susceptible to failure in the face of earthquakes and other seismic activity.

They also highlight that the layers formed at a time when temperatures in Antarctica were up to 3°C warmer than they are today, when sea levels were higher and ice sheets much smaller than at present.

Researchers identify 10 pesticides toxic to neurons involved in Parkinson’s

Photo Credit: Rosyid Arifin

Researchers at UCLA Health and Harvard have identified 10 pesticides that significantly damaged neurons implicated in the development of Parkinson’s disease, providing new clues about environmental toxins’ role in the disease.

While environmental factors such as pesticide exposure have long been linked to Parkinson’s, it has been harder to pinpoint which pesticides may raise risk for the neurodegenerative disorder. Just in California, the nation’s largest agricultural producer and exporter, there are nearly 14,000 pesticide products with over 1,000 active ingredients registered for use.

Through a novel pairing of epidemiology and toxicity screening that leveraged California’s extensive pesticide use database, UCLA and Harvard researchers were able to identify 10 pesticides that were directly toxic to dopaminergic neurons. The neurons play a key role in voluntary movement, and the death of these neurons is a hallmark of Parkinson’s.

Further, the researchers found that co-exposure of pesticides that are typically used in combinations in cotton farming were more toxic than any single pesticide in that group.

'Charge Density Wave' Linked to Atomic Distortions in Would-be Superconductor

This image shows the positions of atoms (blue spheres) that make up the crystal lattice of a copper-oxide superconductor, superimposed on a map of electronic charge distribution (yellow is high charge density, dark spots are low) in charge-ordered states. Normally, the atoms can vibrate side-to-side (shadows represent average locations when vibrating). But when cooled to the point where the ladder-like charge density wave appears, the atomic positions shift along the "rungs" and the vibrations cease, locking the atoms in place. Understanding these charge-ordered states may help scientists unlock other interactions that trigger superconductivity at lower temperatures.
Illustration Credit: Courtesy of Brookhaven National Laboratory

Precision measurements reveal connection between electron density and atomic arrangements in charge-ordered states of a superconducting copper-oxide material

What makes some materials carry current with no resistance? Scientists are trying to unravel the complex characteristics. Harnessing this property, known as superconductivity, could lead to perfectly efficient power lines, ultrafast computers, and a range of energy-saving advances. Understanding these materials when they aren’t superconducting is a key part of the quest to unlock that potential.

“To solve the problem, we need to understand the many phases of these materials,” said Kazuhiro Fujita, a physicist in the Condensed Matter Physics & Materials Science Department of the U.S. Department of Energy’s Brookhaven National Laboratory. In a new study just published in Physical Review X, Fujita and his colleagues sought to find an explanation for an oddity observed in a phase that coexists with the superconducting phase of a copper-oxide superconductor.

Scientists unearth forgotten children of the past

One of the team of scientists analyzing hair under the microscope
Photo Credit: Courtesy of University of York

Scientists have unearthed a story of forgotten children of the past, providing the first direct evidence of the lives of early nineteenth-century ‘pauper apprentices'.

A team from the University of York in collaboration with Durham University and volunteer researchers at Washburn Heritage Centre, examined human remains from a rural churchyard cemetery in the village of Fewston, North Yorkshire. 

Analysis

The analysis discovered the skeletal remains of over 150 individuals, including an unusually large proportion of children aged between eight and 20 years. 

Early analysis immediately identified the children as being distinctive from the locals, showing signs of stunted growth and malnutrition, as well as evidence of diseases associated with hazardous labor. 

The team of scientists, working together with local historians, have been able to piece together the story of these forgotten children, transported from workhouses in London and indentured to work long hours in the mills of the North of England. They were used as an expendable and cheap source of labor.

Adult Friendships Can Triumph Over Childhood Trauma, Even in Baboons

Members of a baboon group in Amboseli, Kenya, relax and groom together, a baboon's way of social bonding.
Photo Credit: Susan C. Alberts, Duke University

Decades of research show that experiencing traumatic things as a child -- such as having an alcoholic parent or growing up in a tumultuous home -- puts you at risk for poorer health and survival later in life.

But mounting evidence suggests that forging strong social relationships can help mitigate these effects. And not just for people, but for our primate cousins, too.

Drawing on 36 years of data, a new study of nearly 200 baboons in southern Kenya finds that adversity early in life can take years off their lifespan, but strong social bonds with other baboons in adulthood can help get them back.

“It’s like the saying from the King James Apocrypha, ‘a faithful friend is the medicine of life,’” said senior author Susan Alberts, professor of biology and evolutionary anthropology at Duke University.

Baboons who had challenging childhoods were able to reclaim two years of life expectancy by forming strong friendships.

The findings were published May 17 in the journal Science Advances.

New study explains how a common virus can cause multiple sclerosis

Olivia Thomas and Mattias Bronge
Photo Credit: Erik Holmgren

Researchers at Karolinska Institutet have found further evidence for how the Epstein-Barr virus can trigger multiple sclerosis or drive disease progression. A study published in Science Advances shows that some individuals have antibodies against the virus that mistakenly attacks a protein in the brain and spinal cord.

The Epstein-Barr virus (EBV) infects most people early in life and then remains in the body, usually without causing symptoms. The link between EBV and the neurological disease multiple sclerosis (MS) was discovered many years ago and has puzzled researchers ever since. Increasing evidence, including two papers published in Science and Nature last year, suggests that EBV infection precedes MS and that antibodies against the virus may be involved. However, the molecular mechanisms seem to vary between patients and remain largely unknown.

“MS is an incredibly complex disease, but our study provides an important piece in the puzzle and could explain why some people develop the disease,” says Olivia Thomas, postdoctoral researcher at the Department of Clinical Neuroscience, Karolinska Institutet and shared first author of the paper. “We have discovered that certain antibodies against the Epstein-Barr virus, which would normally fight the infection, can mistakenly target the brain and spinal cord and cause damage.”

How Breast Cancer Arises

Breast cancer: polyploid giant cancer cell (PGCC)
Image Credit: National Cancer Institute

In what may turn out to be a long-missing piece in the puzzle of breast cancer, Harvard Medical School researchers have identified the molecular sparkplug that ignites cases of the disease currently unexplained by the classical model of breast-cancer development.

A report on the team’s work is published May 17 in Nature.

“We have identified what we believe is the original molecular trigger that initiates a cascade culminating in breast tumor development in a subset of breast cancers that are driven by estrogen,” said study senior investigator Peter Park, professor of Biomedical Informatics in the Blavatnik Institute at HMS.

The researchers said as many as one-third of breast cancer cases may arise through the newly identified mechanism.

The study also shows that the sex hormone estrogen is the culprit behind this molecular dysfunction because it directly alters a cell’s DNA.

Most, though not all, breast cancers are fueled by hormonal fluctuations. The prevailing view of estrogen’s role in breast cancer is that it acts as a catalyst for cancer growth because it stimulates the division and proliferation of breast tissue, a process that carries the risk for cancer-causing mutations. The new work, however, shows that estrogen causes mischief in a far more direct manner.

Genetic research offers new perspective on the early evolution of animals

Some representatives of comb jellies - (a) Beroe ovata, (b) Euplokamis sp., (c) Nepheloctena sp., (d) Bathocyroe fosteri, (e) Mnemiopsis leidyi, and (f) Ocyropsis sp.
Image Credits: a, b, e, f: Joseph F. Ryan; c: R. Griswold, National Oceanic and Atmospheric Administration; d: Marsh Youngbluth, National Oceanic and Atmospheric Administration.

Mapping gene linkages provides clear-cut evidence for comb jellies as sibling group to all other animals

A study published by University of Vienna and MBARI researchers and their collaborators today in Nature provides new insights into one of the earliest points in animal evolution that happened more than 700 million years ago.

For more than a century, scientists have been working to understand the pivotal moment when an ancient organism gave rise to the diverse array of animals in the world today. As technology and science have advanced, scientists have investigated two alternative hypotheses for which animals—sponges or comb jellies, also known as ctenophores—were most distantly related to all other animals. Identifying this outlier—known as the sibling group—has long eluded scientists.

In the new study, a team of researchers from MBARI, the University of Vienna, the University of California, Berkeley, and the University of California, Santa Cruz, mapped sets of genes that are always found together on a single chromosome, in everything from humans and hamsters to crabs and corals, to provide clear evidence that comb jellies are the sibling group to all other animals. Understanding the relationships among animals will help shape our thinking about how key features of animal anatomy, such as the nervous system or digestive tract, have evolved over time.

Radio signal reveals supernova origin

Artist impression of the double star system with a compact white dwarf star accreting matter from a helium-rich donor companion, surrounded by dense and dusty circumstellar material. It was the interaction of the exploded star and the material left over from this companion that gave rise to the strong radio signal, the conspicuous helium lines in the optical spectra and the infrared emission from SN 2020eyj.
Video Credit: Adam Makarenko/W. M. Keck Observatory

In the latest issue of the journal Nature, an international team including astronomers from University of Turku reveal the origin of a thermonuclear supernova explosion. Strong emission lines of helium and the first detection of such a supernova in radio waves show that the exploding white dwarf star had a helium-rich companion.

Thermonuclear (Type Ia) supernovae are important for astronomers since they are used to measure the expansion of the Universe. However, the origin of these explosions remains an open question. While it is established that the explosion is that of a compact white dwarf star somehow accreting too much matter from a companion star, the exact process and the nature of the progenitor is not known. The new discovery of supernova SN 2020eyj established that the companion star was a so-called helium star that had lost much of its material just prior to the explosion of the white dwarf.

“Once we saw the signatures of strong interaction with the material from the companion, we tried to detect it also in radio emission”, explains Erik Kool, post-doc at the Department of Astronomy at Stockholm University and lead author of the paper. “The detection in radio is actually the first one of a Type Ia supernova – something astronomers have tried to do for decades.”

Scales or feathers? It all comes down to a few genes

From left to right: Rory Cooper, a post-doctoral researcher in Michel Milinkovitch’s laboratory, and Michel Milinkovitch, professor in the Department of Genetics and Evolution at the Faculty of Science of the UNIGE. 
Photo Credit: UNIGE

Scales, spines, feathers and hair are examples of vertebrate skin appendages, which constitute a remarkably diverse group of micro-organs. Despite their natural multitude of forms, these appendages share early developmental processes at the embryonic stage. Two researchers from the University of Geneva (UNIGE) have discovered how to permanently transform the scales that normally cover the feet of chickens into feathers, by specifically modifying the expression of certain genes. These results, published in the journal Science Advances, open new perspectives for studying mechanisms that have enabled radical evolutionary transitions in form among species.

The skin of terrestrial vertebrates is adorned with diverse keratinized appendages, such as hair, feathers, and scales. Despite the diversity of forms within and among species, the embryonic development of skin appendages typically begins in a very similar way. Indeed, all of these structures develop from cells that produce a localized thickening on the skin surface and express particular genes. One of these genes, called Sonic hedgehog (Shh), controls a signaling pathway - a communication system that allows the transmission of messages within and between cells. Shh signaling is involved in the development of diverse structures, including the neural tube, limb buds and skin appendages.