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Monday, November 3, 2025

New switch for programmed cell death identified

During the analysis work: Prof. Franz Hagn (left) and Dr. Umut Günsel
Photo Credit: Astrid Eckert / TUM 

In the fight against disease, programmed cell death – also known as apoptosis – is a key protective function of the body. It breaks down cells that are damaged or have undergone dangerous changes. However, cancer cells often manage to override this mechanism. A research team at the Technical University of Munich (TUM) has now succeeded in identifying a new molecular switch in this process and elucidating how it works.

The activation and deactivation of apoptosis is a promising field of research in basic biomedical research. The team led by Prof. Franz Hagn from the Chair of Structural Membrane Biochemistry at the TUM School of Natural Sciences has now discovered a new switch: "Many research teams worldwide are working on the exciting topic of apoptosis and its targeted control. The big advantage is that we are dealing with a highly efficient, evolutionarily developed regulatory mechanism. So, we don't have to invent something completely new, but can use the appropriate structural methods to learn from nature's optimized processes."

Researchers in Japan Discover New Jellyfish Species Deserving of a Samurai Warrior Name

Physalia mikazuki sp. nov., a newly described Portuguese man-of-war collected from Gamo Beach, Sendai Bay. The gas-filled float and long trailing tentacles are characteristic of the Portuguese man-of-war. Runner-up names with a similar Sendai-oriented cultural flare included Physalia: zunda shake, blue dragon, and one-eyed dragon.
Image Credit: © Tohoku University / Cheryl Lewis Ames et al.

A student-led research group from Tohoku University has discovered a new species of the venomous Physalia (commonly known as Portuguese man-of-war) that has never been seen before in northeast Japan. This revelation suggests that warming coastal waters and shifting ocean currents are influencing the distribution of marine organisms in northeastern Japan.

"I was working on a completely different research project around Sendai Bay in the Tohoku region, when I came across this unique jellyfish I had never seen around here before," remarks second author Yoshiki Ochiai. "So, I scooped it up, put it in a ziplock bag, hopped on my scooter, and brought it back to the lab!"

The crystal that makes clouds rain

The experiments have to be performed in the dark
Photo Credit: Technische Universität Wien

No one can control the weather, but certain clouds can be deliberately triggered to release rain or snow. The process, known as cloud seeding, typically involves dispersing small silver iodide particles from aircraft into clouds. These particles act as seeds on which water molecules accumulate, forming ice crystals that grow and eventually become heavy enough to fall to the ground as rain or snow.

Until now, the microscopic details of this process have remained unclear. Using high-resolution microscopy and computer simulations, researchers at TU Wien have investigated how silver iodide interacts with water at the atomic scale. Their findings reveal that silver iodide exposes two fundamentally different surfaces, but only one of them promotes ice nucleation. The discovery deepens our understanding of how clouds form rain and snow and may guide the design of improved materials for inducing precipitation.

Dark matter does not defy gravity

Map of the distribution of galaxies observed by the DESI collaboration, from which it is possible to accurately measure the velocities of galaxies.
Image Credit: © Claire Lamman/DESI collaboration; custom colormap package by cmastro.

Does dark matter follow the same laws as ordinary matter? The mystery of this invisible and hypothetical component of our Universe — which neither emits nor reflects light — remains unsolved.  A team involving members from the University of Geneva (UNIGE) set out to determine whether, on a cosmological scale, this matter behaves like ordinary matter or whether other forces come into play. Their findings, published in Nature Communications, suggest a similar behavior, while leaving open the possibility of an as-yet-unknown interaction. This breakthrough sheds a little more light on the properties of this elusive matter, which is five times more abundant than ordinary matter.

Ordinary matter obeys four well-identified forces: gravity, electromagnetism, and the strong and weak forces at the atomic level. But what about dark matter? Invisible and elusive, it could be subject to the same laws or governed by a fifth, as yet unknown force.

Dark matter falls into gravitational wells in the same way as ordinary matter, thus obeying Euler's equations.

Sunday, November 2, 2025

What Is: The Human Microbiome

The Human Microbiome
Image Credit: Scientific Frontline stock image

The Invisible Organ

The human body is not a sterile, solitary entity. It is a dense, complex, and dynamic ecosystem. Each individual serves as a host to a vast community of microorganisms, collectively known as the human microbiota. This community, which resides in and on the body, is estimated to comprise between 10 trillion and 100 trillion symbiotic microbial cells. Early estimates, which have become a cornerstone of the field, suggested these microbial cells outnumber human cells by a ratio of ten to one. While more recent analyses propose a ratio closer to 1:1, the sheer scale of this microbial colonization remains staggering. These microbial cells, though only one-tenth to one-hundredth the size of a human cell, may account for up to five pounds of an adult's body weight.

This vast microbial community is not a passive passenger. It functions as a "virtual organ" of the body, or more precisely, a "metabolic organ". It is so deeply integrated into our physiology that we are dependent on it for essential life functions, including digestion, immune system development, and the production of critical nutrients.