Super Strong Magnetic Fields Leave Imprint on Nuclear Matter

Collisions of heavy ions generate an immensely strong electromagnetic field. Scientists investigate traces of this powerful electromagnetic field in the quark-gluon plasma (QGP), a state where quarks and gluons are liberated from the colliding protons and neutrons.
Illustration Credit: Tiffany Bowman and Jen Abramowitz/Brookhaven National Laboratory

A new analysis by the STAR collaboration at the Relativistic Heavy Ion Collider (RHIC), a particle collider at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory, provides the first direct evidence of the imprint left by what may be the universe’s most powerful magnetic fields on “deconfined” nuclear matter. The evidence comes from measuring the way differently charged particles separate when emerging from collisions of atomic nuclei at this DOE Office of Science user facility.

As described in the journal Physical Review X, the data indicate that powerful magnetic fields generated in off-center collisions induce an electric current in the quarks and gluons set free, or deconfined, from protons and neutrons by the particle smashups. The findings give scientists a new way to study the electrical conductivity of this “quark-gluon plasma” (QGP) to learn more about these fundamental building blocks of atomic nuclei.

“This is the first measurement of how the magnetic field interacts with the quark-gluon plasma (QGP),” said Diyu Shen, a STAR physicist from Fudan University in China and a leader of the new analysis. In fact, measuring the impact of that interaction provides direct evidence that these powerful magnetic fields exist.

Killer instinct drove evolution of mammals’ predatory ancestors

Inostrancevia, a more advanced predatory synapsid and one of the first sabertoothed carnivores, from the late Permian (~259-252 Million years ago). (Display at the Royal Ontario Museum, Canada).
Photo Credit: Suresh A. Singh

The evolutionary success of the first large predators on land was driven by their need to improve as killers, researchers at the University of Bristol and the Open University suggest.

The forerunners of mammals ruled the Earth for about 60 million years, long before the origin of the first dinosaurs. They diversified as the top predators on land between 315–251 million years ago.

Researchers studied the jaw anatomy and body size of carnivorous synapsids, using these traits to reconstruct the likely feeding habits of these ancient predators and chart their ecological evolution through time. They found a major shift in synapsid jaw function roughly 270 million years ago linked to a significant shift in predatory behavior that has important implications for the evolution of our earliest ancestors. 

As herbivores grew larger and faster, carnivores adapted to become bigger and better predators to survive.

“Earlier synapsid predators such as the famous sail backed Dimetrodon, had fairly long jaws with lots of teeth to ensure that once they ensnared their prey, it wouldn’t escape,” explained lead author Dr Suresh Singh based in Bristol’s School of Earth Sciences. “However, we saw a shift in jaw function toward shorter jaws with greater muscle efficiency and fewer teeth that were concentrated at the front of the jaw - these were jaws adapted to deliver deep, powerful bites.

Study shows orchid family emerged in northern hemisphere and thrived alongside dinosaurs

Phallaenopsis orchid in bloom
Photo Credit: John Wiesenfeld

Scientists at the Royal Botanic Gardens in Kew and the University of Portsmouth, along with partners in Latin America, Asia and Australia, have presented an updated family tree of orchids, tracing their origins to the northern hemisphere some 85 million years ago.

The study, published in leading journal New Phytologist, sheds new light on their complex and fascinating evolutionary history, and the authors hope their findings will help inform future orchid conservation planning. 

The orchid family, Orchidaceae, is often lauded by scientists as one of the greatest evolutionary marvels within the plant world. Not only are these flowering plants found on every continent except the Antarctic and in virtually every habitat, including north of the Arctic Circle, but they are also incredibly diverse, with an estimated 29,500 species – nearly three times more than the recognized number of bird species globally.  

It is generally accepted that orchids originated as far back as around 90 million years or more ago, but they were previously thought to have emerged on the supercontinent Gondwana, in what is present-day Australia.

However, the new study indicates their common ancestor may have originated in the northern hemisphere, on the supercontinent Laurasia, before spreading out further into the world.  

3D model: This is how the body’s building blocks are made

Using electron microscopy, scientists have managed to produce a 3D model of a part of the human cell, the ribosome, which is no more than 30 nanometers in diameter.
Graphic Credit: Eva Kummer

Human cells contain ribosomes, a complex machine that produces proteins for the rest of the body. Now the researchers have come closer to understanding how the ribosome works.

“It is amazing that we can visualize the atomic details of the ribosome. Because they are tiny – around 20-30 nanometers.”

So says Associate Professor Eva Kummer from the Novo Nordisk Foundation Center for Protein Research, who is responsible for the new study published in Nature Communications.

And don’t worry if you don’t know how much a nanometer is. It is around one billionth of a meter.

Using electron microscopy, Eva Kummer and her colleagues Giang Nguyen and Christina Ritter have managed to produce a 3D model of a part of the human cell, the ribosome, which is no more than 30 nanometers in diameter.

More specifically, they have taken snapshots of how a ribosome is made.

“It is important to understand how the ribosome is built and how it works, because it is the only cell particle that produces proteins in humans and all other living organisms. And without proteins, life would cease to exist,” says Eva Kummer.

Proteins are the primary building blocks of the human body. Your heart, lungs, brain and basically your whole body is made of proteins produced by the ribosome.

“From the outside, the human body looks pretty simple, but then consider the fact that every part of the body consists of millions of molecules, that are extremely complex, and that they all know what to do – that is pretty breathtaking,” says Eva Kummer.

Side effects of wide scale forestation could reduce carbon removal benefits by up to a third

Combining forestation with other climate mitigation strategies is vital for more effective long-term climate action
Photo Credit: Andrew Coelho

The side effects of large-scale forestation initiatives could reduce the CO2 removal benefits by up to a third, a pioneering study has found.

The research, led by scientists at the University of Sheffield and published today (Thursday 22 February 2024) in the journal Science, provides a new insight into the broader impacts of forestation on the Earth's climate, indicating that its positive impact is potentially smaller than previously thought. 

Carbon removal strategies, such as forestation, alongside greenhouse gas emissions reduction efforts, have been recognized by the IPCC as essential measures to mitigate the risk of dangerous future climate change. 

By simulating global forest expansion with advanced computer modelling techniques, academics from the University of Sheffield, in collaboration with the Universities of Leeds and Cambridge, and NCAR and WWF, found that while forestation increases absorption of carbon dioxide from the atmosphere, other complex Earth System responses could together partially offset these benefits by up to a third.

Dr James Weber, from the University of Sheffield’s School of Biosciences and lead author of the study, said: “The public are bombarded with messages about climate change, and the suggestion that you can plant trees to offset your carbon emissions is widespread. Many businesses now offer to plant a tree with a purchase, and some countries plan to expand, conserve, and restore forests. 

Outsmarting chemo-resistant ovarian cancer

Ovarian Tumor Microenvironment
Image Credit: National Cancer Institute

New approach with nanoparticle starves cells of cholesterol and reduces tumor growth by 50%

Treatment with the nanoparticle reduced ovarian tumor growth by more than 50% in human cells and animal models.

Women diagnosed with ovarian cancer may initially respond well to chemotherapy, but the majority of them will develop resistance to treatment and die from the disease.

Now Northwestern Medicine scientists have discovered the Achilles heel of chemotherapy-resistant ovarian cancer — its hunger for cholesterol — and how to sneakily use that to destroy it.

In a new study, scientists first showed that chemotherapy-resistant ovarian cancer cells and tumors are rich in cholesterol due to an increased uptake of it. They then deployed a synthetic nanoparticle that appeared to the cancer cells as a natural one rich in cholesterol. But when the cancer cells bound the fake particle, the mimic actually blocked cholesterol uptake. Additionally, the scientists showed that reducing cholesterol tricked the cancer cells down a cell death pathway. Treatment with the nanoparticle reduced ovarian tumor growth by more than 50% in human cells and animal models.

Anti-diabetic drugs could lower risk of primary and secondary brain cancer

Photo Credit: Tesa Robbins

Diabetic patients who take anti-diabetic drugs - known as glitazones – long term had a lower risk of primary and secondary brain cancer compared with diabetic patients on other medications, new research led by the University of Bristol has found.

The study, published in BMJ Open, suggests these drugs could be repurposed to prevent brain metastasis in cancer patients who are at high risk of secondary cancers, if the current research is supported by future studies.

PPAR- α agonists (fibrates) and PPAR γ agonists (glitazones) drugs are clinically important due to their widespread safe use to treat high cholesterol (hyperlipidemia) and diabetes.  Previous studies have suggested that fibrates and glitazones may have a role in brain tumor prevention. Given the drug's safety and cost, they have the potential to be repurposed to prevent brain cancers and reduce the risk of secondary tumors by stopping tumor growth.

Using primary care records from the UK GP database Clinical Practice Research Datalink (CPRD), which contains data from a network of over 2,000 GPs from more than 670 practices across the UK, the researchers examined if this theory could be supported.

Snakes do it faster, better

An Australian “snake-lizard” (Lialis burtonis).This species shares numerous similarities with snakes, including loss of limbs and highly flexible skull. But it is an entirely different type of reptile. It is, in fact, a gecko, and is only distantly related to snakes. The snake-lizard is a specialized predator of other lizards and thus has a diet that is also more similar to snakes than it is to other lizards. With just two known species, the snake-lizard has undergone very little evolutionary diversification. Snakes, in contrast, have diversified into many hundreds of species in Australia alone.
Photo Credit: Pascal Title, University of Michigan/Stony Brook University.

More than 100 million years ago, the ancestors of the first snakes were small lizards that lived alongside other small, nondescript lizards in the shadow of the dinosaurs.

Then, in a burst of innovation in form and function, the ancestors of snakes evolved legless bodies that could slither across the ground, highly sophisticated chemical detection systems to find and track prey, and flexible skulls that enabled them to swallow large animals.

Those changes set the stage for the spectacular diversification of snakes over the past 66 million years, allowing them to quickly exploit new opportunities that emerged after an asteroid impact wiped out roughly three-quarters of the planet’s plant and animal species.

Air Pollution Hides Increases in Rainfall

Humans have an impact on rainfall through both air pollution and greenhouse gas emissions.
Photo Credit: Patrick Hendry

We know that greenhouse gas emissions like carbon dioxide should increase rainfall. The emissions heat the atmosphere, causing a one-two punch: warmer oceans make it easier for water to evaporate, and warmer air can hold more water vapor, meaning more moisture is available to fall as rain. But for much of the 20th century, that increase in precipitation didn’t clearly show up in the data.

A new study led by researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) finds that the expected increase in rain has been largely offset by the drying effect of aerosols – emissions like sulfur dioxide that are produced by burning fossil fuels, and commonly thought of as air pollution or smog. The research is published today in the journal Nature Communications.

“This is the first time that we can really understand what’s causing extreme rainfall to change within the continental U.S.,” said Mark Risser, a research scientist at Berkeley Lab and one of the lead authors for the study. He noted that until the 1970s, the expected increases to extreme rainfall were offset by aerosols. But the Clean Air Act caused a drastic reduction in air pollution in the United States. “The aerosol masking was turned off quite suddenly. That means rainfall might ramp up much more quickly than we would have otherwise predicted.”

How bats distinguish different sounds

Seba's short-tailed bat (Carollia perspicillata) filters out important signals from ambient sound and distinguishes between echolocation and communication calls.
Photo Credit: Julio Hechavarría, Goethe University Frankfurt

Bats live in a world of sounds. They use vocalizations both to communicate with their conspecifics and for navigation. For the latter, they emit sounds in the ultrasonic range, which echo and enable them to create an “image" of their surroundings. Neuroscientists at Goethe University Frankfurt have now discovered how Seba's short-tailed bat, a species native to South America, manages to filter out important signals from ambient sound and especially to distinguish between echolocation and communication calls. 

Seba's short-tailed bat (Carollia perspicillata) lives in the subtropical and tropical forests of Central and South America, where it mostly feeds on pepper fruit. The animals spend their days in groups of 10 to 100 individuals in hollow trunks and rocky caverns, and at night they go foraging together. They communicate using sounds that create distinct ambient noise in the colony – like the babble of voices at a lively party. At the same time, the bats also use vocalizations to navigate their surroundings: a phenomenon known as echolocation, for which they emit ultrasonic sounds that reflect off solid surfaces. The animals then assemble these echoes into an “image" of their surroundings.