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The branch of mathematics known as topology has become a cornerstone of modern physics thanks to the remarkable—and above all reliable—properties it can impart to a material or system. Unfortunately, identifying topological systems, or even designing new ones, is generally a tedious process that requires exactly matching the physical system to a mathematical model.

Researchers at the University of Amsterdam and the École Normale Supérieure of Lyon have demonstrated a model-free method for identifying topology, enabling the discovery of new topological materials using a purely experimental approach. The research is published in the journal Proceedings of the National Academy of Sciences.

Topology encompasses the properties of a system that cannot be changed by any “smooth deformation.” As you might be able to tell from this rather formal and abstract description, topology began its life as a branch of mathematics. However, over the last few decades physicists have demonstrated that the mathematics underlying topology can have very real consequences. Topological effects can be found in a wide range of physical systems, from individual electrons to large-scale .

A University of Massachusetts Amherst team has made a major advance toward modeling and understanding how intrinsically disordered proteins (IDPs) undergo spontaneous phase separation, an important mechanism of subcellular organization that underlies numerous biological functions and human diseases.

IDPs play crucial roles in cancer, neurodegenerative disorders and infectious diseases. They make up about one-third of proteins that human bodies produce, and two-thirds of cancer-associated proteins contain large, disordered segments or domains. Identifying the hidden features crucial to the functioning and self-assembly of IDPs will help researchers understand what goes awry with these features when diseases occur.

In a paper published in the Journal of the American Chemical Society, senior author Jianhan Chen, professor of chemistry, describes a novel way to simulate separations mediated by IDPs, an important process that has been difficult to study and describe.

Albert Einstein was one smart cookie; there’s no doubt about it. But even he knew his general theory of relativity – the 21st century’s answer to Newton’s universal theory of gravity – wasn’t perfect.

Like the second-hand car you bought using your first paycheck, it does the job for day-to-day errands. Push it too hard up a steep hill or park it near a quantum strip mall, and that engine shudders to a standstill.

Peoples’ Friendship University of Russia astrophysics grad student Hamidreza Fazlollahi’s solution is to dive under the hood and see which components aren’t as essential as they seem.

In 1,859, French astronomer and mathematician Urbain Le Verrier detected something strange: Mercury deviated in its dance around the Sun, defying the orderly precession predicted by Newtonian physics.

This odd anomaly couldn’t be explained by unknown planets tugging at Mercury’s orbit; only by physicist Albert Einstein’s 1915 general theory of relativity, which describes how gravity creates curves in the fabric of space-time.

Einstein’s general theory has held strong in the century since, but there are a few things about the Universe his mind-bending model can’t explain. It breaks down in the centers of black holes and at the dawn of the Universe, for example, and doesn’t fit very easily with quantum mechanics, leading some physicists to ponder alternative takes on how gravity works.

In chemistry, structure is everything. Compounds with the same chemical formula can have different properties depending on the arrangement of the molecules they’re made of. And compounds with a different chemical formula but a similar molecular arrangement can have similar properties.

Graphene and a form of called hexagonal boron nitride fall into the latter group. Graphene is made up of . Boron nitride, BN, is composed of boron and nitrogen atoms. While their chemical formulas differ, they have a similar structure —so similar that many chemists call hexagonal boron nitride “white graphene.”

Carbon-based graphene has lots of useful properties. It’s thin but strong, and it conducts heat and electricity very well, making it ideal for use in electronics.

Researchers with the Department of Energy’s SLAC National Accelerator Laboratory, Stanford University and the DOE’s Lawrence Berkeley National Laboratory (LBNL) have grown a twisted multilayer crystal structure for the first time and measured the structure’s key properties. The twisted structure could help researchers develop next-generation materials for solar cells, quantum computers, lasers and other devices.

“This structure is something that we have not seen before—it was a huge surprise to me,” said Yi Cui, a professor at Stanford and SLAC and co-author of a paper published in Science describing the work. “A new quantum electronic property could appear within this three-layer twisted structure in future experiments.”

Researchers at the University of Augsburg and the University of Vienna have discovered co-existing magnetic skyrmions and antiskyrmions of arbitrary topological charge at room temperature in magnetic Co/Ni multilayer thin films. Their findings have been published in Nature Physics and open up the possibility for a new paradigm in skyrmionics research.

The discovery of novel spin objects with arbitrary topological charge promises to contribute to advances in fundamental and applied research, particularly through their application in information storage devices.

Magnetic skyrmions are localized, stable topological magnetic spin textures resembling a tornado-like whirl in a magnetic material. They can be very small, with diameters in the nanometer range, and behave as particles that can be moved, created, and annihilated, which makes them suitable for ‘abacus’-type applications in information storage and logic devices.

A team of biochemists at the Medical Research Council Laboratory of Molecular Biology at Cambridge has developed a new method to incorporate structurally unusual amino acids into proteins by using bacteria. The method is described in the journal Nature.

Prior research has shown that DNA codes for just 20 , the for making all the proteins used by living creatures. These are known as alpha amino acids. Prior research has also suggested that beneficial compounds could be created with a method to create proteins using beta amino acids. Researchers have suggested that applications could include the development of new kinds of medicines and possibly novel catalysts for .

Such proteins have been engineered via syntheses in the lab. but scientists would prefer a more natural approach, which would be both cheaper and more efficient. This means that a technique is required to get a living cell to generate a desired using a beta amino acid.

Tisch Cancer Institute researchers have discovered that a certain type of chemotherapy improves the immune system’s ability to fight off bladder cancer, particularly when combined with immunotherapy.

These findings, published in Cell Reports Medicine, may explain why the approach, chemotherapy, can lead to a cure in a small subset of patients with metastatic, or advanced, . Researchers also believe that their findings could explain why combining another type of chemotherapy, carboplatin-based chemo, with immunotherapy have not been successful but others that use cisplatin with immunotherapy are successful.

“We have known for decades that cisplatin works better than carboplatin in bladder cancer, however, the mechanisms underlying those clinical observations have remained elusive until now,” said the study’s lead author Matthew Galsky, M.D., Co-Director of the Center of Excellence for Bladder Cancer at The Tisch Cancer Institute at Mount Sinai.