Ancient 'Shark' from China Is Humans' Oldest Jawed Ancestor

Life reconstruction of Fanjingshania renovata.
Image Credit: ZHANG Heming)

Paleontologists discover a 439-million-year-old 'shark' that forces us to rethink the timeline of vertebrate evolution

Living sharks are often portrayed as the apex predators of the marine realm. Paleontologists have been able to identify fossils of their extinct ancestors that date back hundreds of millions of years to a time known as the Palaeozoic period. These early "sharks," known as acanthodians, bristled with spines. In contrast to modern sharks, they developed bony "armor" around their paired fins.

A recent discovery of a new species of acanthodian from China surprised scientists with its antiquity. The find predates by about 15 million years the earliest acanthodian body fossils and is the oldest undisputed jawed fish.

These findings were published in Nature.

Reconstructed from thousands of tiny skeletal fragments, Fanjingshania, named after the famous UNESCO World Heritage Site Fanjingshan, is a bizarre fish with an external bony "armor" and multiple pairs of fin spines that set it apart from living jawed fish, cartilaginous sharks and rays, and bony ray- and lobe-finned fish.

Making lab-grown brain organoids ‘brainier

 Slices of mini–brain organoids with neural stem cells (red) and cortical neurons (green).
Credit: Hajime Ozaki, Watanabe lab/UCI

By using stem cells to grow miniature brain-like organs in the lab, scientists have opened a new avenue for studies of neurological development, disease and therapies that can’t be conducted in living people. But not all mini–brain organoids are created equal and getting them to precisely mimic the human brain tissues they’re modeling has been a persistent challenge.

“Right now, it’s like the Wild West because there is no standard method for generating mini–brain organoids,” said Bennett Novitch, a member of the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA and the senior author of a new paper on the topic. “Every neuroscientist wants to make a brain organoid model of their favorite disease, and yet everyone’s organoids do not always look alike.”

In fact, because there is no common protocol for their production and a lack of quality-control guidelines, organoids can vary from lab to lab — and even from batch to batch — which means that a finding made in one organoid may not hold true in another.

“If my lab and another lab down the hall were to conduct drug screens using mini–brain organoid models of the same disorder, we could still get different results,” said Momoko Watanabe, the new paper’s first author and an assistant professor of anatomy and neurobiology at UC Irvine. “We won’t know whose findings are correct because the differences we’re seeing could be reflections of how our models differ rather than reflections of the disease.”

Wildfire smoke exposure hurts learning outcomes

Exposure to fine particle pollution from wildfire smoke during the school day affects average test scores. In this map of the predicted effect on average test scores by district in a relatively high-smoke year, 2016, darker shades indicate a stronger impact.
Image credit: Wen et al. 2022, Nature Sustainability

Pollution from wildfires is linked to lower test scores and possibly lower future earnings for kids growing up with more smoke days at school, a new study finds. Impacts of smoke exposure on earnings are disproportionately borne by economically disadvantaged communities of color.

When wildfire smoke pollutes the air in schoolyards and classrooms, as it does with increasing frequency and severity across the country, it hurts not only children’s health but also their ability to learn and possibly their future earning power, according to new research from Stanford University.

The new analysis, published Sept. 29 in Nature Sustainability, draws on eight years of standardized test scores from nearly 11,700 public school districts across six grades, as well as estimates of daily smoke exposure derived from satellite measurements.

The researchers found test scores in English language arts and math dropped significantly during school years even at low levels of smoke exposure, and that test-score impacts grew as students’ smoke exposure worsened.

The impact on test scores nearly doubled when students were exposed to heavy smoke during the school day compared to the weekend. Underscoring previous studies suggesting that air pollution impacts are particularly harmful for younger students, the study also revealed greater impacts for third to fifth graders compared to sixth to eighth graders.

WVU engineers bring new life to electronics recycling, address supply chain shortfalls affecting national defense

Edward Sabolsky, WVU Benjamin M. Statler College of Engineering and Mineral Resources professor uses ceramic bricks to conduct research at his lab. The U.S. Department of Defense has tasked Sabolsky and Terence Musho with developing a new process for recycling electronic waste in order to extract raw materials that are used to build technology critical to U.S. national defense, such as semiconductors. Photo Credit: WVU /Brian Persinger

West Virginia University researchers are resurrecting discarded electronics, recycling electronic waste and recovering minerals from it to make new products critical for national defense.

Terence Musho, associate professor of mechanical and aerospace engineering at the Benjamin M. Statler College of Engineering and Mineral Resources, is leading the project, which received more than $250,000 from the Defense Advanced Research Projects Agency at the U.S. Department of Defense.

The U.S. currently depends on countries like China to provide raw materials that are essential to electronics enabling its national defense. But according to Musho, that “reliance on foreign national resources has led to the White House identifying a critical shortage in the semiconductor supply chain.”

Musho said that shortage is one reason the DOD is eyeing readily available electronic waste like old “LEDs and microelectronic circuits used for amplifying radio frequencies, which contain critical supply chain materials.”

A Different Kind of Therapy for Stroke

Stroke folders and labels at the Emergency Department at UConn Health in Farmington on Sept. 29, 2020.
Photo Credit: Peter Morenus/UConn

Stroke deprives the brain of oxygen and energy, causing a cascade of spreading cell death. Blocking a specific receptor could contain the damage, researchers from UConn Health and the National Institutes of Health (NIH) report in the Journal of Medicinal Chemistry.

A stroke occurs when a blood vessel in the brain is either ruptured or clogged. The loss of blood flow deprives part of the brain of oxygen, and cells begin to die within minutes. Every 40 seconds someone in the US has a stroke, according to the Centers for Disease Control and Prevention. That’s more than 795,000 people every year. More than half of the survivors will have permanent difficulties walking, talking and caring for themselves.

The faster someone suffering from a stroke gets medical help, the more likely they are to avoid serious lasting disability. Restoring blood flow to the brain as fast as possible to avoid cell death is critical.

But other factors besides blood flow can also contribute to cell death in brain during a stroke. For example, brain cells store lots of energy in the form of the molecule ATP. When a brain cell dies, it releases all of its stored ATP. The spilled ATP triggers a receptor called P2X4 on neighboring brain cells. If the P2X4 receptor is overstimulated, it can trigger a rush of calcium ions that can activate cell death enzymes and set off a destructive cycle of brain damage.

Process converts polyethylene bags, plastics to polymer building blocks

Plastics made from polyethylene (white strands), such as the milk bottle shown in background, can now be broken down into smaller molecules — propylene — that are valuable for making another type of plastic, polypropylene. Click image for more detailed caption.
Graphic credit: Brandon Bloomer, UC Berkeley

Polyethylene plastics — in particular, the ubiquitous plastic bag that blights the landscape — are notoriously hard to recycle. They’re sturdy and difficult to break down, and if they’re recycled at all, they’re melted into a polymer stew useful mostly for decking and other low-value products.

But a new process developed at the University of California, Berkeley, and Lawrence Berkeley National Laboratory (Berkeley Lab) could change all that. The process uses catalysts to break the long polyethylene (PE) polymers into uniform chunks — the three-carbon molecule propylene — that are the feedstocks for making other types of high-value plastic, such as polypropylene.

The process, admittedly in the early stages of development, would turn a waste product — not only plastic bags and packaging, but all types of PE plastic bottles — into a major product in high demand. Previous methods to break the chains of polyethylene required high temperatures and gave mixtures of components in much lower demand. The new process could not only lower the need for fossil fuel production of propylene, often called propene, but also help fill a currently unmet need by the plastics industry for more propylene.

Flaring allows more methane into the atmosphere than we thought

Multiple flares observed in operation in the Bakken Formation in the Williston Basin in North Dakota, 2021.
Image credit: Alan Gorchov Negron, University of Michigan and Yulia Chen of Stanford University

Oil and gas producers rely on flaring to limit the venting of natural gas from their facilities, but new research led by the University of Michigan shows that in the real world, this practice is far less effective than estimated—releasing five times more methane in the U.S. than previously thought.

Methane is known to be a powerful greenhouse gas, but burning it off at oil and gas wells was believed to effectively keep it from escaping into the atmosphere.

Unfortunately, data published in the journal Science shows we overestimate flaring’s effectiveness and, as a result, underestimate its contribution to methane emissions and climate change. But if we fix flaring issues, the payoff is huge: the equivalent of removing 3 million cars from the roads.

Industry and regulators operate under the assumption flares are constantly lit and that they burn off 98% of methane when in operation. Data taken via aerial surveys in the three U.S. geographical basins, which are home to more than 80% of U.S. flaring operations, shows both assumptions are incorrect. Flares were found to be unlit approximately 3%-5% of the time and, even when lit, they were found operating at low efficiency. Combined, those factors lead to an average effective flaring efficiency rate of only 91%.

Power supply: Understand unstable networks

A stable power grid is essential for a reliable and sustainable energy system.
Photo credit: Markus Breig / KIT

A sustainable energy supply requires the expansion of the power grids. However, new lines can also make networks not more stable as expected, but more unstable. The phenomenon is called Braess paradox. This has now been simulated for the first time in detail for power grids, demonstrated on a larger scale and developed a forecasting instrument by an international team in which researchers from the Karlsruhe Institute of Technology (KIT) are also involved. It is intended to support network operators in making decisions. The researchers report in the journal Nature Communications. 

The sustainable transformation of the energy system requires an expansion of the networks in order to integrate renewable sources and to transport electricity over long distances. This expansion requires large investments and aims to make the networks more stable. By upgrading existing lines or adding new lines, it can also happen that the network does not become more stable, but more unstable and there are power outages. “We then speak of the Braess paradox. This means that an additional option instead of improvement leads to a deterioration in the overall situation,” says Dr. Benjamin Schäfer, head of the research group Data-driven Analysis of Complex Systems (DRACOS) at the Institute for Automation and Applied Computer Science at KIT.

The phenomenon is named after the German mathematician Dietrich Braess, who first discussed it for road networks: under certain conditions, the construction of a new road can extend the travel time for all road users. This effect was observed in traffic systems and discussed for biological systems, but has so far only been theoretically forecast for power grids and presented on a very small scale.

Genetic and environmental factors contribute to the overlap between depression and endocrine metabolic diseases

Credit: Pixabay

Depression is common in individuals with endocrine-metabolic disorders and vice versa. In a study of 2.2 million individuals in the Swedish population, researchers at Karolinska Institutet saw that those with endocrine-metabolic diseases also have an increased incidence of depression. The researchers also found higher frequencies of depression in the group's siblings. The study is published in the American Journal of Psychiatry.

Further analyzes described the relative contribution of genetic and environmental factors underlying the concomitant occurrence of depression for a variety of endocrine-metabolic diseases. It is already known that there is an increased simultaneous occurrence of endocrine-metabolic diseases and depression, but the relationships are still unclear.

Whether the overlap between these conditions is mainly genetic or environmental has consequences for whether the development of pharmacological or behavioral interventions would be more effective for treatment or prevention, says Sarah Bergen, senior researcher at the Department of Medical Epidemiology and Biostatistics at Karolinska Institutet, who led the study.

New light for shaping electron beams

Recent experiments at the University of Vienna show that light (red) can be used to arbitrarily shape electron beams (yellow), opening new possibilities in electron microscopy and metrology.
Credit: stefaneder.at, University of Vienna

A new technique that combines electron microscopy and laser technology enables programable, arbitrary shaping of electron beams. It can potentially be used for optimizing electron optics and for adaptive electron microscopy, maximizing sensitivity while minimizing beam-induced damage. This fundamental and disruptive technology was now demonstrated by researchers at the University of Vienna, and the University of Siegen. The results are published in PRX.

When light passes through turbulent or dense material, e.g. the Earth’s atmosphere or a millimeter-thick tissue, standard imaging technologies experience significant limitations in the imaging quality. Scientists therefore place deformable mirrors in the optical path of the telescope or microscope, which cancel out the undesired effects. This so-called adaptive optics has led to many breakthroughs in astronomy and deep-tissue imaging.

However, this level of control has not yet been achieved in electron optics even though many applications in materials science and structural biology demand it. In electron optics, scientists use beams of electrons instead of light to image structures with atomic resolution. Usually, static electromagnetic fields are used to steer and focus the electron beams.

Webb and Hubble Capture Detailed Views of DART Impact

For the first time, the NASA/ESA/CSA James Webb Space Telescope and the NASA/ESA Hubble Space Telescope have taken simultaneous observations of the same target.  These images, Hubble on left and Webb on the right, show observations of Dimorphos several hours after NASA’s Double Asteroid Redirection Test (DART) intentionally impacted the moonlet asteroid. It was the world’s first test of the kinetic impact technique using a spacecraft to deflect an asteroid by modifying its orbit.  Both Webb and Hubble observed the asteroid before and after the collision took place.  Scientists will use the combined observations from Hubble and Webb to gain knowledge about the nature of the surface of Dimorphos, how much material was ejected by the collision, how fast it was ejected, and the distribution of particle sizes in the expanding dust cloud.  In the coming months, scientists will also use Webb’s Mid-Infrared Instrument (MIRI) and Near-Infrared Spectrograph (NIRSpec) to observe Dimorphos further. Spectroscopic data will provide researchers with insight into the asteroid’s composition. Hubble will monitor Dimorphos ten more times over the next three weeks to monitor how the ejecta cloud expands and fades over time.  Hubble observations were conducted in one filter, WFC3/UVIS F350LP (assigned the color blue), while Webb observed at F070W (0.7 microns, assigned the color red). 
Credit: NASA, ESA, CSA, and STScI

Two of the great observatories, the NASA/ESA/CSA James Webb Space Telescope and the NASA/ESA Hubble Space Telescope, have captured views of a unique experiment to smash a spacecraft into a small asteroid. NASA’s Double Asteroid Redirection Test (DART) impact observations mark the first time that Webb and Hubble were used to simultaneously observe the same celestial target.

On 26 September 2022 at 13:14 CEST, DART intentionally crashed into Dimorphos, the asteroid moonlet in the double-asteroid system of Didymos. It was the world’s first test of the kinetic impact technique using a spacecraft to deflect an asteroid by modifying the object’s orbit. DART is a test for defending Earth against potential asteroid or comet hazards.

The observations are more than just an operational milestone for each telescope—there are also key science questions relating to the makeup and history of our solar system that researchers can explore when combining the capabilities of these observatories.

Adverse health outcomes associated with long-term antidepressant use

Long-term antidepressant use may double the risk of heart disease, finds the most comprehensive epidemiological study to date to investigate the health consequences from using the medication over ten years. The University of Bristol-led study, published in the British Journal of Psychiatry Open, analyzed data on over 200,000 people.

Antidepressants are one of the most widely prescribed drugs in England. In 2018, over 70-million antidepressant prescriptions were dispensed. The striking rise in prescribing (nearly doubling in a decade) is due mainly to long-term treatment rather than increased diagnosis. However, little is known about the health consequences of long-term use of these medicines.

Researchers from Bristol’s Centre for Academic Mental Health aimed to find out if long-term antidepressant use (over five and ten years) was associated with the onset of six health problems: diabetes, high blood pressure, coronary heart disease, stroke and related syndromes, and two mortality outcomes (death from cardiovascular disease and from any cause).

Using data from UK Biobank, a large-scale biomedical database and research resource containing anonymized genetic, lifestyle and health information from half a million UK participants, the team linked comprehensive health data with prescription and disease data (using GP records) on 222,121 adults aged between 40 to 69-years old.

Less bird diversity in city forests

Image credit: Kev

A new study led by Lund University in Sweden shows that cities negatively affect the diversity of birds. There are significantly fewer bird species in urban forests compared with forests in the countryside - even if the forest areas are of the same quality.

The researchers examined 459 natural woodlands located in or near 32 cities in southern Sweden. They counted the occurrence of different bird species, and the result is clear: in natural forests located in a city center, there are on average a quarter fewer species of forest birds compared to forests outside the city. In terms of endangered species, about half as many species were found in urban forests compared to rural forests.

The results deepen our knowledge of the impact of cities on biodiversity, says William Sidemo Holm, one of the researchers behind the study. It is already well known that urbanization is one of the main driving forces behind the loss of biodiversity, as cities spread out across the globe. What is not as well known, however, is how cities affect protected natural areas in a city.

“Our study demonstrates that you cannot surround nature with urban development and believe that it will remain as it is, there is going to be a negative effect”, says William Sidemo Holm, who worked on the study during his time as a doctoral student at Lund University.

Birth of a sibling triggers long-lasting stress in young bonobos

Young bonobos as old as eight years suffer long-lasting stress after the birth of a sibling. 
Credit: MPI of Animal Behavior/ Christian Ziegler

In any family, the birth of a child is a transformative event, often greeted with positive feelings from parents—and mixed feelings from siblings. The arrival of a new brother or sister, and the loss of parental attention that comes with it, is stressful for any first-born child. Now, scientists have shown that it is not just humans who have trouble becoming siblings. Bonobos, our closest living relatives, also experience stress in the transition to siblinghood. Following the birth of a sibling, young bonobos had five times higher levels of the stress hormone cortisol and a reduced immune response, which lingered for months. The international team of researchers behind the study were able to show that the stress response was due to the birth of siblings, and not to the natural weaning process that young bonobos inevitably go through. The study on wild bonobos, which is the first to investigate physiological changes in an animal as it transitions to siblinghood, reveals similarities between humans and bonobos—and an evolutionary history behind the stressful event of becoming a sibling.

Bonobos (Pan paniscus) are a species of great ape found only in the Congolese rainforest. Like humans, bonobos and other great apes take an unusually long time to reach independence. Bonobos rely on their mothers for food and protection for eight years and only reach full adulthood at 12 years. While in most animals, offspring are weaned before the mother gives birth to another infant. In bonobos, maturation is slow and the birth of another baby happens long before the older infant has become independent—setting the scene for sibling rivalry.

How fish survive the extreme pressures of life in the oceans

Photo credit: Milos Prelevic

Scientists have discovered how a chemical in the cells of marine organisms enables them to survive the high pressures found in the deep oceans.

The deeper that sea creatures live, the more inhospitable and extreme the environment they must cope with. In one of the deepest points in the Pacific - the Mariana Trench, 11 kilometers below the sea surface - the pressure is 1.1 kbar or eight tons per square inch. That is a 1,100-fold increase of the pressure experienced at the Earth’s surface.

Under normal or atmospheric pressure, water molecules form a tetrahedron-like network. At high pressure, though, the network of water molecules begins to distort and change shape. When this happens to the water inside living cells, it prevents vital bio-chemical processes from taking place - and kills the organism.

Our study provides a bridge between water under pressure at the molecular level and the wonderful ability of organisms which thrive under high pressure in depths of the oceans.

In reporting their findings, the researchers in Leeds have for the first time been able to provide an explanation of how a molecule found in the cells of marine organisms counteracts the effect of external pressure on the water molecules.