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Researchers from the University of Waterloo have proposed a new method to measure the Hubble constant that could help resolve one of modern cosmology’s pressing puzzles: the Hubble tension.

The study published in Physical Review Letters aims to resolve the Hubble tension, a discrepancy between the value of the Hubble constant (H0) from the local (distance ladder) method and the (CMB) method.

Phys.org spoke to the first author of the study, Dr. Alex Krolewski, a postdoctoral researcher at the University of Waterloo.

Scientists trying to discover the elusive mass of neutrinos, tiny “ghost particles” that could solve some of the universe’s biggest mysteries, announced a new limit on Thursday for how much they could weigh, halving the previous estimate.

Since the existence of was proposed nearly a century ago, scientists around the world have struggled to learn much about them—particularly their mass.

This is important because the neutrino, as the most abundant particle in the universe, “weaves a thread that connects the infinitely small and the infinitely large,” Thierry Lasserre, a physicist at France’s Alternative Energies and Atomic Energy Commission, told AFP.

A team of biomaterial engineers, environmental resource specialists and industrial design researchers affiliated with a host of institutions across Japan has developed a biodegradable material that is clear and can hold boiling water—and it degrades in less than a year after settling on the ocean floor. Their work is published in the journal Science Advances.

Prior research has shown that millions of tons of plastics are piling up in the environment, including on the . Because of this, scientists have been looking for better, biodegradable replacements. In this new effort, the research team has developed a paper-based, clear, that can stand up to liquids for several hours, even those that have been heated, allowing them to replace plastic cups, straws, and other everyday objects.

The research team made the material by starting with a standard cellulose hydrogel. After drying, the material was treated with an aqueous lithium bromide solution which forced the cellulose to solidify into desired shapes. The researchers note that end-products could be as thin as plastic cup walls, or as thick as desired. They describe the material as tPB, a transparent 3D material made solely of cellulose.

During the latter part of the 20th century, string theory was put forward as a unifying theory of physics foundations. String theory has not, however, fulfilled expectations. That is why we are of the view that the scientific community needs to reconsider what comprises elementary forces and particles.

Since the early days of general relativity, leading physicists, like Albert Einstein and Erwin Schrödinger, have tried to unify the theory of gravitation and electromagnetism. Many attempts were made during the 20th century, including by Hermann Weyl.

Finally, it seems that we have found a unified framework to accommodate the theory of electricity and magnetism within a purely geometric theory. This means that electromagnetic and are both manifestations of ripples and curvatures in .

Are we alone in the universe? The answer to one of humanity’s biggest questions is complicated by a basic reality: If there is life on other worlds, it may not look familiar. A sample of rocks from Mars or another planet almost certainly won’t have recognizable fossils or another similarly obvious sign of living organisms, said Mikhail Tikhonov, an assistant professor of physics in Arts & Sciences at Washington University in St. Louis who studies microbial communities.

But just because we might not recognize signs of life on a distant moon or planet doesn’t mean it’s actually lifeless. “There could be life forms out there that defy our imagination,” Tikhonov said.

Searching for life that we don’t understand may seem like an impossible mission. In a paper published in Nature Communications, Tikhonov and co-author Akshit Goyal of the International Centre for Theoretical Science in Bengaluru, India, propose a new idea. Instead of looking for particular molecules or compounds associated with life as we know it, scientists can look for telltale patterns of energy.

Cytochrome P450 (CYP) proteins are responsible for breaking down more than 80% of all Food and Drug Administration (FDA)-approved drugs, reducing their effectiveness. However, how to prevent CYPs from doing this without off-target effects has puzzled researchers until now.

Scientists at St. Jude Children’s Research Hospital have designed new drug frameworks that selectively target CYP3A4, one of the most critical CYP proteins. Structural insights from this work offer a roadmap for future drug developers to better evaluate and selectively target CYP proteins. The findings are published in Nature Communications.

CYP3A4 breaks down drugs that treat various health conditions, including the anti-cancer agent paclitaxel and the COVID-19 therapeutic nirmatrelvir. CYP3A4 are commonly co-administered to reduce CYP3A4’s effect. This includes ritonavir, which is combined with nirmatrelvir in Paxlovid for mild COVID-19 treatment. However, such CYP3A4 inhibitors often affect the similar but distinct CYP3A5 due to the two proteins’ shared features, such as large and promiscuous binding sites, in addition to other unintended CYPs.

For decades, scientists assumed that neural stem cells (NSCs) only occur in the brain and spinal cord. A new international study, led by Hans Schöler of the Max Planck Institute for Molecular Biomedicine in Münster, has now refuted this assumption and discovered a new type of neural stem cell outside the central nervous system (CNS) that opens up enormous possibilities for the development of therapies for neurological diseases. The study is published in the journal Nature Cell Biology.

In 2014, an article titled “Stimulus-triggered fate conversion of into pluripotency” was published in Nature. This publication initially caused quite a stir because it opened up a simple way to obtain . The induction of pluripotent stem cells without the need for viral vectors, as Shinya Yamanaka had done and for which he received the Nobel Prize, would have been too good to be true.

Although the laboratory of Schöler at the Max Planck Institute for Molecular Biomedicine, like many others, tried to repeat the experiment that described the “stimulus-triggered acquisition of pluripotency” (STAP) based on treating somatic cells with low pH. However, the generation of pluripotent cells failed regardless of the culture conditions and tissues used—and the corresponding paper was eventually retracted several months after publication.

Quantum computers, which process information leveraging quantum mechanical effects, have the potential to outperform classical computers in some optimization and computational tasks. In addition, they could be used to simulate complex quantum systems that cannot be simulated using classical computers.

Researchers at Quantinuum and other institutes in Europe and the United States recently set out to simulate the digitized dynamics of the quantum Ising model, a framework that describes in materials, using an advanced quantum computer.

Their simulations, outlined in a paper on the arXiv preprint server, led to the observation of a transient state known as Floquet prethermalization, in which systems appear locally stable before approaching full equilibrium, in regimes that are inaccessible to classical computers.

Bioinformaticians from Heinrich Heine University Düsseldorf (HHU) and the university in Linköping (Sweden) have established that the genes in bacterial genomes are arranged in a meaningful order. In the journal Science, they explain that the genes are arranged by function: If they become increasingly important for faster growth, they are located near the origin of DNA replication. Accordingly, their position influences how their activity changes with the growth rate.

Are genes distributed randomly along the , as if scattered from a salt shaker? This opinion, which is held by a majority of researchers, has now been disputed by a team of bioinformaticians led by Professor Dr. Martin Lercher, head of the research group for Computational Cell Biology at HHU.

When bacteria replicate their in preparation for , the process starts at a specific point on the bacterial chromosome and continues along the chromosome in both directions.

Proteins are the building blocks of life. They consist of folded peptide chains, which in turn are made up of a series of amino acids. From stabilizing cell structure to catalyzing chemical reactions, proteins have many functions. Their diversity is further increased by modifications that take place after the peptide chains have been synthesized.

One form of modification is protein splicing. The protein initially contains a so-called “intein,” which removes itself from the peptide chain to ensure the correct folding and function of the final protein.

A team led by protein chemist Prof Henning Mootz and Ph.D. student Christoph Humberg from the Institute of Biochemistry at the University of Münster has now answered a long-standing research question: Why does a special variant of the inteins, the “split inteins,” often encounter problems in the laboratory that significantly lower the efficiency of the reaction? The researchers were able to identify protein misfolding as one cause and have developed a method to prevent it.