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Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:33pm

"In accelerator physics, the thinking is often in only one plane," Franchetti says. In order to map a resonance, however, the particle beam needs to be measured across both the horizontal and the vertical planes.

It sounds pretty straightforward, but if you're used to thinking about something a specific way, it might take an effort to think outside the box. Understanding the effects of resonance on a particle beam took quite a few years, and some hefty computer simulations.

However, that information opened the way for Franchetti, along with physicists Hannes Bartosik and Frank Schmidt of CERN, to finally measure the magnetic anomaly.

Using beam position monitors along the Super Proton Synchrotron, they measured the position of the particles for approximately 3,000 beams. By carefully measuring where the particles were centered, or skewed to one side, they were able to generate a map of the resonance haunting the accelerator.

Part 3

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:32pm

Resonance occurs when two systems interact and sync up. It could be a resonance emerging between planetary orbits as they gravitationally interact in their journey around a star, or a tuning fork that starts to sympathetically ring when sound waves from another tuning fork hit its tines.

Particle accelerators use powerful magnets that generate electromagnetic fields to guide and accelerate beams of particles to where physicists want them to go. Resonances can occur in the accelerator due to imperfections in the magnets, creating a magnetic structure that interacts with particles in problematic ways.

The more degrees of freedom a dynamic system exhibits, the more complex it is to describe mathematically. Particles moving through a particle accelerator are usually described using just two degrees of freedom, reflecting the two coordinates needed to define a point on a flat grid.

To describe structures therein requires mapping them using additional features in phase space beyond just the up-down, left-right dimensions; that is, four parameters are needed to map each point in the space.

This, the researchers say, is something that could very easily "elude our geometric intuition".

Part 2

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 12:31pm

Physicists Capture Elusive 4D 'Ghost' in CERN Particle Accelerator

There's a specter haunting the tunnels of a particle accelerator at CERN.

In the Super Proton Synchrotron, physicists have finally measured and quantified an invisible structure that can divert the course of the particles therein, and create problems for particle research.

It's described as taking place in phase space, which can represent one or more states of a moving system. Since four states are required to represent the structure, the researchers view it as four-dimensional.

This structure is the result of a phenomenon known as resonance, and being able to quantify and measure it takes us a step closer to solving a problem universal to magnetic particle accelerators.

"With these resonances, what happens is that particles don't follow exactly the path we want and then fly away and get lost," says physicist Giuliano Franchetti of GSI in Germany. "This causes beam degradation and makes it difficult to reach the required beam parameters."

Part 1

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 11:32am

Pregnancy advances a woman's ‘biological’ age — but giving birth turns it back

Carrying a baby creates some of the same epigenetic patterns on DNA seen in older people.

Carrying a baby in the womb leads to changes in the distribution of certain chemical markers on a pregnant person’s DNA — changes similar to those that are a hallmark of getting older. But new research shows that, several months after a person gives birth, the chemical patterns revert to an earlier state. The results strengthen previous work in mice and preliminary results in humans.

The chemical tags analysed in the study are called methyl groups, and they are added to DNA in a process called methylation. They are one example of the ‘epigenome’, features of DNA that change gene activity without altering the genetic code.
DNA-methylation patterns can be used to estimate a person’s ‘biological age’, which reflects the physiological stresses that a person’s body has accrued over time. Some research has found that biological age is a better predictor of health problems such as cardiovascular disease3 and dementia4 than a person’s chronological age.
But unlike chronological age, “biological age is quite flexible; it’s a fluid parameter. It can go up and down”.

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 11:29am

Pregnancy advances ‘biological age’
Studies in mice and humans suggest that being pregnant can increase a person’s ‘biological age’ by a couple of years — but giving birth reverses these changes. Biological age can be estimated from patterns of DNA methylation, which occurs when chemical methyl groups are added to DNA. The patterns reflect the stresses that a body accrues over time. The work supports the idea that “biological age is quite flexible; it’s a fluid parameter. It can go up and down”, says biomedical scientist Vadim Gladyshev.

https://www.nature.com/articles/d41586-024-00843-w?utm_source=Live+...

https://www.sciencedirect.com/science/article/abs/pii/S155041312400...

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 11:24am

This research shows exposure to microgravity mimics the aging process on a largely physiological level—wasting of bones and muscles, changes in hormonal functioning, and increased susceptibility to infection—but this paper finds that self-motion is mainly unaffected, suggesting the balance issues that frequently come from old age may not be related to the vestibular system.

It suggests that the mechanism for the perception of movement in older people should be relatively unaffected and that the issues involved in falling may not be so much in terms of the perception of how far they've moved, but perhaps more to do with how they're able to convert that into a balance reflex.

Björn Jörges et al, The effects of long-term exposure to microgravity and body orientation relative to gravity on perceived traveled distance, npj Microgravity (2024). DOI: 10.1038/s41526-024-00376-6

Part 2

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 11:23am

Astronauts have surprising ability to know how far they 'fly' in space

New research finds that astronauts have a surprising ability to orient themselves and gauge distance traveled while free from the pull of gravity.

The findings of the study, done in collaboration with the Canadian Space Agency and NASA, have implications for crew safety in space and could potentially give clues to how aging affects people's balance systems here on Earth.

It has been repeatedly shown that the perception of gravity influences perceptual skill. The most profound way of looking at the influence of gravity is to take it away, which is why the researchers took their research into space.

Based on these findings it seems as though humans are surprisingly able to compensate adequately for the lack of an Earth-normal environment using vision.

The researchers studied a dozen astronauts aboard the International Space Station, which orbits about 400 kilometers from the Earth's surface.

Here, Earth's gravity is approximately canceled out by centrifugal force generated by the orbiting of the station. In the resulting microgravity, the way people move is more like flying. People have previously anecdotally reported that they felt they were moving faster or further than they really were in space, so this provided some motivation actually to record this.

The researchers compared the performance of a dozen astronauts—six men and six women—before, during, and after their year-long missions to the space station and found that their sense of how far they traveled remained largely intact.

The study, published recently in npj Microgravity, has been a decade in the making and represents the first of three papers that will emerge from the research investigating the effects of microgravity exposure on different perceptual skills including the estimation of body tilt, traveled distance, and object size.

part1

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 11:12am

The world is one step closer to secure quantum communication on a global scale

Researchers have brought together two Nobel prize-winning research concepts to advance the field of quantum communication.

Scientists can now efficiently produce nearly perfect entangled photon pairs from quantum dot sources. The research, "Oscillating photonic Bell state from a semiconductor quantum dot for quantum key distribution," was published in Communications Physics.

Entangled photons are particles of light that remain connected, even across large distances, and the 2022 Nobel Prize in Physics recognized experiments on this topic. Combining entanglement with quantum dots, a technology recognized with the Nobel Prize in Chemistry in 2023, the IQC research team aimed to optimize the process for creating entangled photons, which have a wide variety of applications, including secure communications.

By embedding semiconductor quantum dots into a nanowire, the researchers created a source that creates near-perfect entangled photons 65 times more efficiently than previous work.

This new source can be excited with lasers to generate entangled pairs on command. The researchers then used high-resolution single photon detectors provided by Single Quantum in The Netherlands to boost the degree of entanglement.

Using their new quantum dot entanglement source, the researchers simulated a secure communications method known as quantum key distribution, proving that the quantum dot source holds significant promise in the future of secure quantum communications.

Matteo Pennacchietti et al, Oscillating photonic Bell state from a semiconductor quantum dot for quantum key distribution, Communications Physics (2024). DOI: 10.1038/s42005-024-01547-3

Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 10:29am

Over a human lifespan, the modeled impacts of the suppression bias outweigh those from fuel accumulation or climate change alone. This suggests that suppression may exert a significant and underappreciated influence on patterns of fire globally.

Fire suppression exacerbated the trends already caused by climate change and fuel accumulation, the study found, causing areas burned to increase three to five times faster over time relative to a world with no suppression.

Suppression, through preferentially removing low- and moderate-severity fire, also raised average fire severity by an amount equivalent to a century of fuel accumulation or climate change.

"By attempting to suppress all fires, we are bringing a more severe future to the present", say the researchers.

However, the new findings also show that allowing more low- and moderate-intensity fire can reduce or reverse the impacts of the suppression bias. Suppression strategies that allow fire to burn under moderate weather conditions—while still suppressing fires during more dangerous fire weather—reduced average fire severity and moderated the rate of burned area increase, the team found.

Developing and implementing technologies and strategies to safely manage wildfires during moderate burning conditions is essential. This approach may be just as effective as other necessary interventions, like mitigating climate change and decreasing unintentional human-related ignitions.

 Kreider, M.R., et al. Fire suppression makes wildfires more severe and accentuates impacts of climate change and fuel accumulation. Nature Communications (2024). doi.org/10.1038/s41467-024-46702-0

Part 2

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Comment by Dr. Krishna Kumari Challa on March 26, 2024 at 10:27am

 Unintended consequences of fire suppression

The escalation of extreme wildfires globally has prompted a critical examination of wildfire management strategies. A new study reveals how fire suppression ensures that wildfires will burn under extreme conditions at high severity, exacerbating the impacts of climate change and fuel accumulation.

The study used computer simulations to show that attempting to suppress all wildfires results in fires burning with more severe ecological impacts, with accelerated increases in burned area beyond those expected from fuel accumulation or climate change.

Fire suppression has unintended consequences, say the researchers. We've known for a long time that suppressing fires leads to fuel accumulation. Here, the researchers show a separate counter-intuitive outcome.

Though fire suppression reduces the overall area burned, it mainly eliminates low- and moderate-intensity fires. As a result, the remaining fires are biased to be more extreme. The study, "Fire suppression makes wildfires more severe and accentuates impact...," published in Nature Communications, shows how this "suppression bias" causes average fire severity to increase substantially.

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