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Dense crowds form some of the most dangerous environments in modern society. Dangers arise from uncontrolled collective motions, leading to compression against walls, suffocation and fatalities. Our current understanding of crowd dynamics primarily relies on heuristic collision models, which effectively capture the behaviour observed in small groups of people. However, the emergent dynamics of dense crowds, composed of thousands of individuals, remains a formidable many-body problem lacking quantitative experimental characterization and explanations rooted in first principles. Here we analyse the dynamics of thousands of densely packed individuals at the San Fermín festival (Spain) and infer a physical theory of dense crowds in confinement. Our measurements reveal that dense crowds can self-organize into macroscopic chiral oscillators, coordinating the orbital motion of hundreds of individuals without external guidance. Guided by these measurements and symmetry principles, we construct a mechanical model of dense-crowd motion. Our model demonstrates that emergent odd frictional forces drive a non-reciprocal phase transition7 towards collective chiral oscillations, capturing all our experimental observations. To test the robustness of our findings, we show that similar chiral dynamics emerged at the onset of the 2010 Love Parade disaster and propose a protocol that could help anticipate these previously unpredictable dynamics.

UMD researchers have discovered key mechanisms in gene regulation that could improve the design of RNA-based medicines.

RNA-based medicines are among the most promising approaches to combating human disease, as evidenced by the recent successes of RNA

Ribonucleic acid (RNA) is a polymeric molecule similar to DNA that is essential in various biological roles in coding, decoding, regulation and expression of genes. Both are nucleic acids, but unlike DNA, RNA is single-stranded. An RNA strand has a backbone made of alternating sugar (ribose) and phosphate groups. Attached to each sugar is one of four bases—adenine (A), uracil (U), cytosine ©, or guanine (G). Different types of RNA exist in the cell: messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA).

Crowdsourcing treatments that work — yael elish — CEO & founder, stuffthatworks.


Yael Elish is CEO and Founder of StuffThatWorks (https://www.stuffthatworks.health/), a company that offers an online platform where people suffering from chronic diseases can share information to learn which treatments work best for their specific condition, based on the experience of their peers combined with a smart, AI-based crowdsourcing system.

A passionate entrepreneur with expertise in crowdsourcing and consumer-facing products, Yael was on the Waze founding team, where she drove the overall product strategy that led the company from User One to one of the world’s most notable crowdsourcing endeavours. She also co-founded eSnips and NetSnippet, and was part of the senior management team that took Commtouch to its successful NASDAQ IPO in 2000.

Prior to Commtouch, Yael led the sales and marketing efforts for various start-ups in Israel.

Yael holds a first degree in Foreign Relations from the Hebrew University of Jerusalem, Israel.

Weill Cornell Medicine investigators have identified in a preclinical model a specific brain circuit whose inhibition appears to reduce anxiety without side effects. Their work suggests a new target for treating anxiety disorders and related conditions and demonstrates a general strategy, based on a method called photopharmacology, for mapping drug effects on the brain.

In their study, published Jan. 28 in Neuron, the researchers examined the effects of experimental drug compounds that activate a type of brain-cell receptor called the metabotropic glutamate receptor 2 (mGluR2). While these receptors are found on neurons within many brain circuits, the team showed that activating them in a specific circuit terminating in an emotion-related brain region called the amygdala reduces signs of anxiety without apparent adverse side effects. Current treatments for anxiety disorders, panic disorder and associated conditions can have unwanted side effects including cognitive impairments.

“Our findings indicate a new and important target for the treatment of anxiety-related disorders and show that our photopharmacology-based approach holds promise more broadly as a way to precisely reverse-engineer how therapeutics work in the brain,” said study senior author Dr. Joshua Levitz, an associate professor of biochemistry at Weill Cornell Medicine.

The aim of the following paper was to overview the body-composition-related changes and molecular effects of different chemotherapy agents used in cancer treatment on skeletal-muscle remodeling.

— Pedrosa, et al.

Full text is available


Paraneoplastic conditions such as cancer cachexia are often exacerbated by chemotherapy, which affects the patient’s quality of life as well as the response to therapy. The aim of this narrative review was to overview the body-composition-related changes and molecular effects of different chemotherapy agents used in cancer treatment on skeletal-muscle remodeling. A literature search was performed using the Web of Science, Scopus, and Science Direct databases and a total of 77 papers was retrieved. In general, the literature survey showed that the molecular changes induced by chemotherapy in skeletal muscle have been studied mainly in animal models and mostly in non-tumor-bearing rodents, whereas clinical studies have essentially assessed changes in body composition by computerized tomography.

Electric sparks are used for welding, powering electronics, killing germs or for igniting the fuel in some car engines. Despite their usefulness, they are hard to control in open space—they split into chaotic branches that tend to go toward the closest metallic objects.

A recent study published in Science Advances uncovers a way of transporting electricity through air by . The level of control of the electric sparks allows guidance of the spark around obstacles, or guiding it to hit specific spots, even in non-conductive materials.

“We observed this phenomenon more than one year ago, then it took us months to control it, and even longer to find an explanation,” says Dr. Asier Marzo from the Public University of Navarre, lead researcher of the work.

The largest solar storm in two decades hit Earth in May 2024. For several days, wave after wave of high-energy charged particles from the sun rocked the planet. Brilliant auroras engulfed the skies, and some GPS communications were temporarily disrupted.

With the help of a serendipitously resurrected small NASA satellite, scientists have discovered that this also created two new temporary belts of energetic particles encircling Earth. The findings are important to understanding how future solar storms could impact our technology.

The new belts formed between two others that permanently surround Earth called the Van Allen Belts. Shaped like high above Earth’s equator, these permanent belts are composed of a mix of high-energy electrons and protons that are trapped in place by Earth’s magnetic field. The energetic particles in these belts can damage spacecraft and imperil astronauts who pass through them, so understanding their dynamics is key to safe spaceflight.

An interesting paper where Schuette et al. develop a generative diffusion-based AI model for predicting the 3D structure of chromatin. Their model takes chromatin accessibility sequence data as input and outputs a statistical distribution of predicted 3D chromatin structures. Remarkably, their model generalizes across cell types, making it broadly useful! #computationalbiology #ai #generativeai


Computational approaches for predicting chromatin conformations de novo using only sequencing data remain scarce. Compared to existing polymer simulation–based prediction approaches, ChromoGen maintains unique advantages. The generative nature of ChromoGen enables efficient production of statistically independent samples, thus avoiding the inefficient navigation of state space that polymer simulations require to produce a diverse set of conformations. Moreover, ChromoGen’s transformer-based front end provides additional advantages, extracting features from sequencing data and placing the information in low-dimensional embeddings that the diffusion model handles efficiently. This powerful design markedly reduces the computational cost of each diffusion step, providing a practical means to achieve cell type–specific de novo predictions with the full benefit of DNA sequence and chromatin accessibility data. In contrast, incorporating DNA sequence information into polymer models has long been a challenging task that is often indirectly addressed by incorporating various histone marks.

In its current form, ChromoGen can be immediately applied to any cell type with available DNAse-seq data, enabling a vast number of studies into the heterogeneity of genome organization both within and between cell types to proceed. However, several improvements could enhance its utility. Notably, the current model exclusively predicts chromatin conformations in 1.28-Mb regions at 20-kb resolution, the latter restriction primarily stemming from our decision to maximize resolution within the constraints imposed by the available Dip-C data. However, higher-resolution single-cell datasets are becoming available, such as those at 5-kb resolution (50), and we anticipate that ChromoGen will require no modifications to perform well after training on these improved datasets. Similarly, we anticipate that ChromoGen can be directly applied to longer genomic regions if using a lower resolution, e.g.

Published in the Journal of the American Chemical Society, the research by scientists at King’s College London and their collaborators suggests that chromatin—the complex of DNA

DNA, or deoxyribonucleic acid, is a molecule composed of two long strands of nucleotides that coil around each other to form a double helix. It is the hereditary material in humans and almost all other organisms that carries genetic instructions for development, functioning, growth, and reproduction. Nearly every cell in a person’s body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA).

Dairy cattle in Nevada have been infected with a new type of bird flu that’s different from the version that has spread in U.S. herds since last year, Agriculture Department officials said Wednesday.

The detection indicates that distinct forms of the virus known as Type A H5N1 have spilled over from wild birds into cattle at least twice. Experts said it raises new questions about wider spread and the difficulty of controlling infections in animals and the people who work closely with them.

“I always thought one bird-to-cow transmission was a very rare event. Seems that may not be the case,” said Richard Webby, an influenza expert at St. Jude Children’s Research Hospital.