Alpine rock reveals dynamics of plate movements in Earth’s interior

Professor Lucie Tajčmanová, Heidelberg University, examines the whiteschist sample from the Dora Maira Massif of the Western Alps.
Photo Credit: Sebastian Cionoiu, Heidelberg University

Examining how plates move in Earth's mantle and how mountains form is no easy feat. Certain rocks that have sunk deep into Earth's interior and then returned from there can deliver answers. Led by the Department of Geosciences at Goethe University Frankfurt, an international team of geologists has now succeeded in analyzing whiteschist from the Alps so precisely by means of computer modeling that it calls a previous theory about plate movement into question. 

Geoscientists analyze rocks in mountain belts to reconstruct how they once moved downwards into the depths and then returned to the surface. This history of burial and exhumation sheds light on the mechanisms of plate tectonics and mountain building. Certain rocks that sink far down into Earth's interior together with plates are transformed into different types under the enormous pressure that prevails there. During this UHP metamorphosis (UHP: Ultra High Pressure), silica (SiO2) in the rock, for example, becomes coesite, which is also referred to as the UHP polymorph of SiO2. Although it is chemically still silica, the crystal lattices are more tightly packed and therefore denser. When the plates move upwards again from the depths, the UHP rocks also come to the surface and can be found in certain places in the mountains. Their mineral composition provides information about the pressures to which they were exposed during their vertical journey through Earth's interior. Using lithostatic pressure as a unit of measurement, it is possible to correlate pressure and depth: the higher the pressure, the deeper the rocks once lay. 

Cancer's sweet Achilles heel

Weakly immunogenic and strongly immunogenic tumor cells were subcutaneously transplanted into B4GALT3 knockout and wild-type mice. Tumor cell growth was significantly suppressed in knockout mice.
Illustration Credit: KyotoU Jake Tobiyama/Heng Wei

An old campaign slogan for cough syrup, "It tastes awful. And it works," seemed to imply that any sweet content might have diminished the medicinal effect.

Sweetness, in the case of cancer, appears as a chain of sugar molecules attached to proteins by beta1,4-galactosyltransferase-3, or B4GALT3. According to the Cancer Genome Atlas, a high expression of this enzyme is associated with noticeably shortened survival rates in several types of immunotherapy cancers, such as neuroblastoma, cervical, and bladder cancer. However, the specific role of B4GALT3 in the tumor immune microenvironment -- or TIME -- was still unknown.

Now, a team of researchers at Kyoto University and Yokohama City University has found that B4GALT3 deficiency in mice TIME inhibits tumor growth. The study shows that a significant reduction of glycosylation -- a type of protein modification -- on T cell surfaces correlates with increases in CD8+ immune cells infiltrating tumors.

Stunting in infancy linked to differences in cognitive and brain function

Photo Credit: bethL

Children who are too short for their age can suffer reduced cognitive ability arising from differences in brain function as early as six months of age, according to new research.

Researchers from the University of Nottingham were part of a team led by the University of East Anglia who compared the ‘visual working memory’ – the memory capacity that holds visual cues for processing – in children who had stunted growth with those having typical growth.

Published today in the journal Nature Human Behavior, the study found that the visual working memory of infants with poor physical growth was disrupted, making them more easily distracted and setting the stage for poorer cognitive ability one year later.

Stunted growth had previously been linked with poor cognitive outcomes later in life, but this is the first time that this association has been found in infancy. It is also the first time stunted growth has been linked to functional differences in how the brain works in early development.

Decoding Past Climates through Dripstones

NATURAL ARCHIVES: “Dripstones, or speleothems, are unique natural archives.
Photo Credit: Zarko Tankosic

A recent study demonstrates how dripstones can be crucial for reconstructing past climates. The new approach can provide a detailed picture of the climate around early human occupations in South Africa.

“Dripstones, or speleothems, are unique natural archives - like Earth’s USB sticks. They store a wealth of information on past climate which helps us to better understand the environment in which early humans lived”, Jenny Maccali explained. She is a scientist at SapienCE Centre of Excellence, and has led the study, now published in Climate of the Past.

New perspective to ancient climate

South Africa has a highly dynamic climate resulting from its position at the convergence of two oceanic basins, the Atlantic Ocean to the west and the Indian Ocean to the east. The region is also located at the boundary of different climate zones (subtropical vs. temperate), and the proximity of the Antarctic ice sheet has a direct impact on its climate by influencing the easterlies and westerlies winds position, and hence rainfall pattern.

Unconventional Approach to C. Diff

C. difficile bacteria seen through a scanning electron microscope and colored green.
Image Credit: Janice Carr via CDC

Clostridioides difficile (C. diff) intestinal infections can cause severe, debilitating diarrhea in patients who are hospitalized or on immunosuppressive therapies. The infections can be very hard to eradicate, roaring back when patients try to taper their antibiotics. Many people wind up on antibiotics for months and can become resistant to three or more of them.

“Often being on antibiotics isn’t sufficient,” explained Meenakshi Rao, Harvard Medical School assistant professor of pediatrics at Boston Children’s Hospital. “The infection can catalyze severe, runaway inflammation, especially in patients with inflammatory bowel disease.”

This inflammation, in turn, promotes C. diff colonization of intestinal tissue. And antibiotics themselves could be part of the problem.

“Once we attack C. diff with antibiotics, it disrupts the gut microbiome,” said Min Dong, HMS associate professor of surgery at Boston Children’s, whose lab studies bacterial toxins and how to combat them. “That creates an opportunity for severe, recurring infection, and it becomes a vicious cycle.”

Venus had Earth-like plate tectonics billions of years ago

Photo Credit: NASA/JPL

A new study found that Venus, a scorching wasteland of a planet according to scientists, may have once had tectonic plate movements similar to those believed to have occurred on early Earth, a new study found. The finding sets up tantalizing scenarios regarding the possibility of early life on Venus, its evolutionary past and the history of the solar system.

Writing in Nature Astronomy, a team of scientists led by Brown University researchers describes using atmospheric data from Venus and computer modeling to show that the composition of the planet’s current atmosphere and surface pressure would only have been possible as a result of an early form of plate tectonics, a process critical to life that involves multiple continental plates pushing, pulling and sliding beneath one another.

On Earth, this process intensified over billions of years, forming new continents and mountains, and leading to chemical reactions that stabilized the planet’s surface temperature, resulting in an environment more conducive to the development of life.

Fruit, nectar, bugs and blood: How bat teeth and jaws evolved for a diverse dinnertime

A side-view image of the skull of a greater spear-nosed bat, Phyllostomus hastatus, a noctilionoid species with an omnivorous diet.
Photo Credit: Sharlene Santana/University of Washington

They don’t know it, but Darwin’s finches changed the world. These closely related species — native to the Galapagos Islands — each sport a uniquely shaped beak that matches their preferred diet. Studying these birds helped Charles Darwin develop the theory of evolution by natural selection.

A group of bats has a similar — and more expansive — evolutionary story to tell. There are more than 200 species of noctilionoid bats, mostly in the American tropics. And despite being close relatives, their jaws evolved in wildly divergent shapes and sizes to exploit different food sources. A paper published in Nature Communications shows those adaptations include dramatic, but also consistent, modifications to tooth number, size, shape and position. For example, bats with short snouts lack certain teeth, presumably due to a lack of space. Species with longer jaws have room for more teeth — and, like humans, their total tooth complement is closer to what the ancestor of placental mammals had.

Breakthrough synthesis method improves solar cell stability

Jin Hou is a Rice University graduate student and lead author on a study published in Nature Synthesis. Photo Credit: Courtesy of Jin Hou

Solar cell efficiency has soared in recent years due to light-harvesting materials like halide perovskites, but the ability to produce them reliably at scale continues to be a challenge.

A process developed by Rice University chemical and biomolecular engineer Aditya Mohite and collaborators at Northwestern University, the University of Pennsylvania and the University of Rennes yields 2D perovskite-based semiconductor layers of ideal thickness and purity by controlling the temperature and duration of the crystallization process.

Known as kinetically controlled space confinement, the process could help improve the stability and reduce the cost of halide perovskite-based emerging technologies like optoelectronics and photovoltaics.

Unlocking Sugar to Generate Biofuels and Bioproducts

Chang-Jun Liu (left) and Nidhi Dwivedi (right) in the Brookhaven Lab greenhouse with rice plants like those used in this study.
Photo Credit: Courtesy of Brookhaven National Laboratory

Plant biologists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have engineered enzymes to modify grass plants so their biomass can be more efficiently converted into biofuels and other bioproducts. As described in a paper just published in Plant Biotechnology Journal, these enzymes modify molecules that make up plant cell walls to provide access to fuel-generating sugars normally locked within complex structures. 

“The concept of biomass to biofuel seems simple, but it is technically very difficult to release the sugars,” noted Chang-Jun Liu, a senior plant biologist at Brookhaven Lab who led the study.

Plant biomass is full of energy-rich complex sugar molecules generated from photosynthesis. Each plant cell is surrounded by a rigid cell wall made of sugars and a material called lignin that provides structural support. Reducing lignin to gain access to the sugars has been the focus of research aimed at using plants to generate fuels and other products commonly made from petroleum.

Endangered whales live in area earmarked for gas exploration

Risso's dolphins.
Photo Credit Leonidas Karantzas/Greenpeace

Endangered whales and dolphins live year-round in an area of the Mediterranean earmarked for oil and gas exploration, new research shows.

Various cetacean species are known to inhabit the Hellenic Trench off Greece in the summer, but until now little has been known about their winter whereabouts.

This lack of information has been used to justify seismic surveys (which may harm whales and dolphins) in winter.

The new study found that at least four species – including the regionally endangered sperm whale – live in the deep waters of the Hellenic Trench in both summer and winter.

The research was carried out in 2021-22 by the Greenpeace Research Laboratories, University of Exeter, Greenpeace Greece and the Pelagos Cetacean Research Institute.

“The Mediterranean is one of the busiest seas on the planet, and whales and dolphins are already threatened by ship strikes, overfishing, bycatch (accidental catching), pollution with chemicals and plastics, and climate change,” said Dr Kirsten Thompson.