Spokes move along Saturn's rings

Spokes move along Saturn's rings
Seven Hubble Space Telescope images, each taken about four minutes apart, are stitched together to show "spoke" features rotating around Saturn. The puzzling, transient features have defied easy characterization. Their rotation rate does not quite match up with the rotation of the rings or of the planet's magnetic field. The spokes are known to appear during the period leading up to and following the planet's equinox. With the northern hemisphere autumnal equinox approaching on May 6, 2025, scientists are hoping new observations by Hubble will help them to put the clues together and solve the spoke mystery—what are they, and why do they form? Hubble observations will be compared with those made by NASA's Cassini spacecraft in the period surrounding Saturn's last equinox, in 2009. With the Cassini mission completed, Hubble's annual observations of Saturn as part of its Outer Planet Atmospheres Legacy (OPAL) program will be crucial to studying and better understanding this dynamic world.
Credits: SCIENCE: NASA, ESA, Amy Simon (NASA-GSFC) ANIMATION: Alyssa Pagan (STScI)

New images of Saturn from NASA's Hubble Space Telescope herald the start of the planet's "spoke season" surrounding its equinox, when enigmatic features appear across its rings. The cause of the spokes, as well as their seasonal variability, has yet to be fully explained by planetary scientists.

Like Earth, Saturn is tilted on its axis and therefore has four seasons, though because of Saturn's much larger orbit, each season lasts approximately seven Earth years. Equinox occurs when the rings are tilted edge-on to the Sun. The spokes disappear when it is near summer or winter solstice on Saturn. (When the Sun appears to reach either its highest or lowest latitude in the northern or southern hemisphere of a planet.) As the autumnal equinox of Saturn's northern hemisphere on May 6, 2025, draws near, the spokes are expected to become increasingly prominent and observable.

Less is more

The ability to genetically change bacteria is the key to researching the microbial world.
Image Credit: Braňo

Scientists from Würzburg and Braunschweig have developed a new approach that enables more efficient processing of bacterial genomes.

The ability to genetically change bacteria is the key to researching the microbial world. Genome editing - i.e. processing the genome such as DNA - is essential in order to develop new antibiotics and to use bacteria as miniature factories for the sustainable production of chemicals, materials and therapeutics. Tools based on the CRISPR gene scissors have proven helpful here because they make it possible to change different bacteria quickly, easily and reliably.

The underlying technology requires CRISPR ribonucleic acid (crRNA), which serves as a "lead RNA". It helps to control certain regions of a genome for targeted DNA cleavage. Proteins involved in homologous recombination - a natural process of exchanging genetic material between chromosomes - then insert the designed "repair template" to create a processed sequence of the DNA strand.

How Giants Became Dwarfs

A nest of empty snail shells with the giant territorial nest owner (right), a female just entering a shell (middle) and a parasitic dwarf male (left). The striped fish in the foreground are egg predators.
Photo Credit: © Sabine Wirtz-Ocana

In certain Lake Tanganyika cichlids breeding in empty snail shells, there are two extreme sizes of males: giants and dwarfs. Researchers from the University of Bern and the University of Graz have analyzed the genomes of these fish and found out how the peculiar sizes of males and females evolved in conjunction with the genetic sex determination mechanism.

Difference in body size (or sexual dimorphism) between males and females is common across the animal kingdom. One of the most extreme examples of sexual dimorphism is found in the cichlid fish species Lamprologous callipterus from Lake Tanganyika in East Africa, where males are 12 times bigger (heavier) than females. The ecological reason for this remarkable size difference is the fact that this species uses empty snail shells found at the bottom of the lake to build nests. Hence males must be large enough to carry shells with their mouths, whereas females need to be small enough to fit inside the snail shells to lay eggs, where they are well protected from predators. Sex-specific differences in body size are important for the biology of this species, as small males would not be able to carry empty snail shells and large females would not be able to enter the shells for breeding.

New approach puts brain scans on the witness stand in trademark disputes

Research shows how neuroscience could reduce bias, revolutionize intellectual property law
Image Credit: creative commons

Imagine you’re browsing the toothpaste aisle and see next to Colgate a new brand called Colddate, packaged in a box with similar colors and designs. “You might think this is clearly a copycat brand,” said Ming Hsu, William Halford Jr. Family Chair in Marketing at the Haas School of Business, UC Berkeley.

Yet in a real-life trademark infringement case involving these two brands, Colgate-Palmolive lost the suit, with the judge saying they were “similar” but not “substantially indistinguishable.”

There are often different opinions between judges and juries in trademark cases about how similar the brands in question actually are, leading to large inconsistencies in the application of the law. In a paper published February 8 in the journal Science Advances, Hsu and colleagues propose a more scientific measure through the use of brain scans—employing functional magnetic resonance imaging (fMRI) along with a specialized technique called repetition suppression (RS).

“Asking the brain, not a person, could reduce—if not eliminate—these inconsistencies,” said lead author Zhihao Zhang, a former Berkeley Haas postdoctoral researcher now on the faculty of the Darden School of Business, University of Virginia. The study’s other authors include Dr. Andrew Kayser of UC San Francisco, Femke van Horen of Vrije University Amsterdam, and Mark Bartholomew of University at Buffalo Law School.

"Snapshots" of Translation Could Help Us Investigate Cellular Proteins

Nascent polypeptide chains or polypeptidyl-tRNAs (pep-tRNAs) occur transiently during protein synthesis. The potential to study these intermediates and better understand their role in processes like gene regulation has been greatly enhanced by the development of a process termed PETEOS—short for peptidyl-tRNA enrichment using organic extraction and silica adsorption. This method, developed by scientists at Tokyo Tech, allows for the large-scale harvesting, processing, and identification of pep-tRNA polypeptide moieties.

Advances in molecular biology have revealed that pep-tRNAs—nascent polypeptides inside the ribosome that are covalently attached to transfer RNA—are involved in a myriad of cell functions, including gene expression. All proteins exist as pep-tRNAs at some point and studying these translation intermediates is vital as they possess properties of both RNA and protein and can help researchers better understand the specifics of translation. Depending on stimuli and/or stresses, translational regulation is very rapid and spans initiation, elongation, and elongation pausing. Garnering deeper insights into the process of translation therefore requires a suitable method to process pep-tRNAs in large quantities. These nuances have fueled the development of molecular tools to investigate cellular translation.

Packaged DNA: MLU researchers develop new method to promote bone growth

Image Credit: Sangharsh Lohakare

DNA can help to stimulate bone healing in a localized and targeted manner, for example after a complicated fracture or after severe tissue loss following surgery. This has been demonstrated by researchers at Martin Luther University Halle-Wittenberg (MLU), the University of Leipzig, the University of Aveiro (Portugal) and the Fraunhofer Institute for Microstructure of Materials and Systems IMWS in Halle. They have developed a new process in which they coat implant materials with a gene-activated biomaterial that induces stem cells to produce bone tissue. Their findings were published in the renowned journal Advanced Healthcare Materials.

Bones are a fascinating example of the body’s ability to regenerate. They are able to regain full functionality - even after a fracture - thanks to their ability to form new, resilient tissue at the fracture site. "However, when it comes to complicated fractures or major tissue loss, even a bone’s self-healing power is insufficient," explains Professor Thomas Groth, head of the Biomedical Materials research group at MLU’s Institute of Pharmacy. "In such cases, implants are needed to stabilize the bone, replace parts of joints, or bridge larger defects with degradable materials." The success of such implants depends largely on how well they are incorporated into the bone. Increased efforts have been made in recent years to support this process by coating implants with bioactive materials to activate bone cells and mesenchymal stem cells. 

Tidal stream power can significantly enhance energy security

A new study reveals the potential of tidal resources to make a marked difference on a community's clean energy ambitions
Needles, Isle of Wight, UK
Photo Credit: Dan

Adopting tidal power alongside other forms of renewable energy can significantly enhance energy security and go some way to enabling communities to fulfil their clean energy ambitions, a new study has shown.

Researchers found that installing tidal stream systems, in addition to solar and offshore wind farms, is around 25% more effective at balancing supply with demand than just relying on solar and wind technologies.

Using tidal technologies as part of a renewable energy mix can also reduce the space required for power-generating facilities, both on land and at sea, by around 33% and significantly reduce their visual impact since much of their operation is below the sea’s surface.

It can also help to reduce the levelized cost of whole-system energy, relative to solar and wind systems, because it reduces the requirement to access expensive reserve supplies.

Nicotine exposure during pregnancy may increase risk of sudden infant death

SNUS
Photo Credit: Bengt Wiberg

Infants whose mothers have used snus (a moist oral tobacco product) during pregnancy run three times the risk of sudden infant death, according to a comprehensive registry study from Karolinska Institutet published in the journal Pediatric Research. The risk was much lower if the mother had stopped taking snus before the first antenatal visit. The researchers conclude that all types of nicotine products should be avoided during pregnancy.

“Fortunately, the incidence of sudden infant death is very low, but we can see that taking snus or smoking while pregnant is associated with an increased risk,” says Anna Gunnerbeck, pediatrician at the Astrid Lindgren Children’s Hospital and researcher at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet.

Studied two million babies

While it is known that smoking during pregnancy is a risk factor in sudden infant death, little research has been done on snus and other nicotine products. To address this, the researchers conducted a registry study comprising over two million babies born in Sweden between 1999 and 2019. During this time, only two out of 10,000 babies suffered sudden infant death, which is when death occurs suddenly for no apparent reason during sleep.

How hepatitis E viruses penetrate cells

It was only around three years ago that a cell culture model was developed that can be used to examine hepatitis E exactly in the laboratory.
Photo Credit: RUB, Marquar

A certain surface protein is important for the cell entry of the hepatitis E virus. Medicines can suppress it.

Although hepatitis E is a common disease, little is known about the life cycle of the virus. A team from Molecular and Medical Virology at the Ruhr University Bochum and Carl von Ossietzky University Oldenburg reports on initial findings on how he manages to infect cells in the journal Hepatology from 7. February 2023. A protein called EGFR, short for Epidermal Growth Factor Receptor, plays a decisive role in the penetration of virus particles into cells. This finding could open up new treatment routes for hepatitis E. Because there are already approved drugs against EGFR that inhibit the activity of this receptor.

Cell culture model makes investigations possible

One of the reasons why hepatitis E has been researched comparatively little is that it was only around three years ago in Bochum and Hanover a robust cell culture model has been developed for its investigation is. Using this model, the researchers were now able to investigate how the virus manages to infect cells.

"With medication, we suppressed the activity of the EGFR protein at the time the virus entered some cell lines," explains first author Jil Alexandra Schrader. “With these cultures, we could see that there were significantly fewer infected cells." The researchers used cell cultures as a cross-check, in which the co-receptor was produced in excess. In this case, there were more infections than untreated cells.

Complications in pregnancy linked to increased risk of heart disease

Photo Credit: freestocks

Certain complications during pregnancy bring an increased risk of heart disease later on. However, there is still much to learn about how arteriosclerosis develops between pregnancy and heart disease later in life. A large new study led by researchers from Lund University in Sweden shows that narrowing and calcification of the blood vessels of the heart are more common in women previously affected by pregnancy complications.

Despite complications in pregnancy having increasingly been acknowledged as a new type of risk factor for heart disease, it is yet to be determined how this information can best be used within healthcare.

“Our results suggest that the correlation exists even among women with a low expected risk of cardiovascular disease. The study is an important piece of the puzzle in understanding how women with pregnancy complications should be followed-up by their healthcare provider after pregnancy,” says Simon Timpka, associate professor of clinical epidemiology who leads the research team Perinatal and Cardiovascular Epidemiology at Lund University and is a resident in obstetrics and gynecology at Skåne University Hospital.