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May 26, 2022

New calculations of solar spectrum resolve decade-long controversy about the sun’s chemical composition

Posted by in categories: chemistry, cosmology, mapping, physics

What do you do when a tried-and-true method for determining the sun’s chemical composition appears to be at odds with an innovative, precise technique for mapping the sun’s inner structure? That was the situation facing astronomers studying the sun—until new calculations that have now been published by Ekaterina Magg, Maria Bergemann and colleagues, and that resolve the apparent contradiction.

The decade-long solar abundance crisis is the conflict between the internal structure of the sun as determined from solar oscillations (helioseismology) and the structure derived from the fundamental theory of stellar evolution, which in turn relies on measurements of the present-day sun’s . The new calculations of the physics of the sun’s atmosphere yield updated results for abundances of different chemical elements, which resolve the conflict. Notably, the sun contains more oxygen, silicon and neon than previously thought. The methods employed also promise considerably more accurate estimates of the chemical compositions of stars in general.

May 26, 2022

What the Voyager space probes can teach humanity about immortality and legacy as they sail through space for trillions of years

Posted by in category: life extension

Voyager 1 is the farthest human-made object from Earth. After sweeping by Jupiter, Saturn, Uranus and Neptune, it is now almost 15 billion miles (24 billion kilometers) from Earth in interstellar space. Both Voyager 1 and its twin, Voyager 2, carry little pieces of humanity in the form of their Golden Records. These messages in a bottle include spoken greetings in 55 languages, sounds and images from nature, an album of recordings and images from numerous cultures, and a written message of welcome from Jimmy Carter, who was U.S. president when the spacecraft left Earth in 1977.

The Golden Records were built to last a billion years in the environment of space, but in a recent analysis of the paths and perils these explorers may face, astronomers calculated that they could exist for trillions of years without coming remotely close to any stars.

Having spent my career in the field of religion and science, I’ve thought a lot about how spiritual ideas intersect with technological achievements. The incredible longevity of the Voyager spacecraft presents a uniquely tangible entry point into exploring ideas of immortality.

May 26, 2022

Carving a Space-Time Crystal in a Plasma

Posted by in category: computing

A theorized scheme uses lasers to produce space-time quasicrystals in a plasma—density fluctuations that could be used as diffraction gratings for high-intensity laser pulses.


In modern computers, errors during processing and storage of information have become a rarity due to high-quality fabrication. However, for critical applications, where even single errors can have serious effects, error correction mechanisms based on redundancy of the processed data are still used.

May 26, 2022

Error-free quantum computing gets real

Posted by in categories: computing, information science, particle physics, quantum physics

In modern computers, errors during processing and storage of information have become a rarity due to high-quality fabrication. However, for critical applications, where even single errors can have serious effects, error correction mechanisms based on redundancy of the processed data are still used.

Quantum computers are inherently much more susceptible to disturbances and will thus probably always require error correction mechanisms, because otherwise errors will propagate uncontrolled in the system and information will be lost. Because the fundamental laws of quantum mechanics forbid copying quantum information, redundancy can be achieved by distributing logical quantum information into an entangled state of several physical systems, for example multiple .

The team led by Thomas Monz of the Department of Experimental Physics at the University of Innsbruck and Markus Müller of RWTH Aachen University and Forschungszentrum Jülich in Germany has now succeeded for the first time in realizing a set of computational operations on two logical quantum bits that can be used to implement any possible operation. “For a real-world quantum , we need a universal set of gates with which we can program all algorithms,” explains Lukas Postler, an experimental physicist from Innsbruck.

May 26, 2022

Cryogenic electron microscopy reveals drug targets against common fungus

Posted by in categories: biotech/medical, genetics

Most people carry the fungus Candida albicans on their bodies without it causing many problems. However, a systemic infection with this fungus is dangerous and difficult to treat. Few antimicrobials are effective, and drug resistance is increasing. An international group of scientists, including Albert Guskov, associate professor at the University of Groningen, have used single-particle cryogenic electron microscopy to determine the structure of the fungal ribosome. Their results, which were published in Science Advances on 25 May, reveal a potential target for new drugs.

Candida albicans usually causes no problems, or just an itchy skin infection that is easily treated. However, in rare cases, it may cause systemic infections that can be fatal. Existing antifungal drugs cause a lot of side effects and are expensive. Furthermore, C. albicans is becoming more drug-resistant, so there is a real need for new drug targets. “We noted that no antifungal drugs are targeting protein synthesis, while half of the antibacterial drugs interfere with this system,” says Guskov. A reason for this is that fungal ribosomes, the cellular machineries that translate the genetic code into proteins, are very similar in humans and fungi. “So, you would need a very selective drug to avoid killing our own cells.”

May 26, 2022

CCR5 is a suppressor for cortical plasticity and hippocampal learning and memory

Posted by in categories: biotech/medical, neuroscience

Repression of the G protein-coupled chemokine receptor CCR5 enhances MAPK/CREB signaling, long-term potentiation, somatosensory cortical plasticity, and learning and memory, while CCR5 over-activation by viral proteins may contribute to HIV-associated cognitive deficits.

May 26, 2022

Giant Magnetic Waves Have Been Discovered Oscillating Around Earth’s Core

Posted by in category: evolution

Earth’s interior is a far from quiet place. Deep below our surface activities, the planet rumbles with activity, from plate tectonics to convection currents that circulate through the hot magmatic fluids far underneath the crust.

Now scientists studying satellite data of Earth have identified something inside Earth we’ve never seen before: a new type of magnetic wave that sweeps around the surface of our planet’s core, every seven years.

Continue reading “Giant Magnetic Waves Have Been Discovered Oscillating Around Earth’s Core” »

May 26, 2022

A new approach to therapy-resistant tumors targets a specific cell-death pathway

Posted by in category: biotech/medical

In a paper appearing in Nature today, an international group of scientists report a new way to kill hard-to-treat cancers. These tumors resist current immunotherapies, including those using Nobel Prize-winning checkpoint-blocking antibodies.

The approach exploits Z-DNA. Rather than twisting to the right like B-DNA, Z-DNA has a left-handed twist. One role for Z-DNA is to regulate the to viruses. The response involves AADR1 and ZBP1, two proteins that specifically recognize Z-DNA. They do so through a Zα domain that binds to the Z-DNA structure with high affinity.

The Zα domain was originally discovered by Dr. Alan Herbert of InsideOutBio, a communicating author on the paper. The ADAR1 Zα domain turns off the , while the other ZBP1 Zα turns on pathways that kill virally infected , as previously shown by Dr. Sid Balachandran, the other communicating author on the paper. The interactions between ADAR1 and ZBP1 determine whether a cell lives or dies.

May 25, 2022

How the universe got its magnetic field

Posted by in categories: cosmology, engineering

When we look out into space, all of the astrophysical objects that we see are embedded in magnetic fields. This is true not only in the neighborhood of stars and planets, but also in the deep space between galaxies and galactic clusters. These fields are weak—typically much weaker than those of a refrigerator magnet—but they are dynamically significant in the sense that they have profound effects on the dynamics of the universe. Despite decades of intense interest and research, the origin of these cosmic magnetic fields remains one of the most profound mysteries in cosmology.

In previous research, scientists came to understand how turbulence, the churning motion common to fluids of all types, could amplify preexisting magnetic fields through the so-called dynamo process. But this remarkable discovery just pushed the mystery one step deeper. If a turbulent dynamo could only amplify an existing field, where did the “seed” magnetic field come from in the first place?

We wouldn’t have a complete and self-consistent answer to the origin of astrophysical magnetic fields until we understood how the seed fields arose. New work carried out by MIT graduate student Muni Zhou, her advisor Nuno Loureiro, a professor of nuclear science and engineering at MIT, and colleagues at Princeton University and the University of Colorado at Boulder provides an answer that shows the basic processes that generate a field from a completely unmagnetized state to the point where it is strong enough for the dynamo mechanism to take over and amplify the field to the magnitudes that we observe.

May 25, 2022

Mechanism Responsible for Information Transfer Between Different Regions of the Brain Discovered

Posted by in category: neuroscience

Summary: Increasing synchronization of neurons in the upstream brain region that transmits information leads to a significant improvement in the transmission of information and information processing in the downstream region.

Source: Bar-Ilan University.

In the early 20th century scientists began to record brain activity using electrodes attached to the scalp. To their surprise, they saw that brain activity is characterized by slow and rapid ascending and descending signals which were subsequently called “brain waves”.