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Comment by Dr. Krishna Kumari Challa on February 1, 2023 at 9:15am

The majority of the results fit perfectly with the currently accepted best theory of the universe.

But there are also signs of a crack—one that has been suggested in the past by other analyses, too.

It seems like there are slightly less fluctuations in the current universe, than we would predict assuming our standard cosmological model anchored to the early universe.

That is, if you make a model incorporating all the currently accepted physical laws, then take the readings from the beginning of the universe and extrapolate it forward through time, the results look slightly different from what we actually measure around us today.

Specifically, today's readings find the universe is less "clumpy"—clustering in certain areas rather than evenly spread out—than the model would predict.

If other studies continue to find the same results, scientists say, it may mean there is something missing from our existing model of the universe, but the results are not yet to the statistical level that scientists consider to be ironclad. That will take further study.

 Y. Omori et al, Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . I. Construction of CMB lensing maps and modeling choices, Physical Review D (2023). DOI: 10.1103/PhysRevD.107.023529

C. Chang et al, Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . II. Cross-correlation measurements and cosmological constraints, Physical Review D (2023). DOI: 10.1103/PhysRevD.107.023530

T. M. C. Abbott et al, Joint analysis of Dark Energy Survey Year 3 data and CMB lensing from SPT and Planck . III. Combined cosmological constraints, Physical Review D (2023). DOI: 10.1103/PhysRevD.107.023531

Part 2

Comment by Dr. Krishna Kumari Challa on February 1, 2023 at 9:14am

Scientists release new map of all the matter in the universe

When the universe began, matter was flung outward and gradually formed the planets, stars and galaxies that we know and love today. Scientists are very interested in tracing the path of this matter; by seeing where all the matter ended up, they can try to recreate what happened and what forces would have had to have been in play. By carefully assembling a map of that matter today, scientists can try to understand the forces that shaped the evolution of the universe.

A group of scientists have released one of the most precise measurements ever made of how matter is distributed across the universe today.

Combining data from two major telescope surveys of the universe, the Dark Energy Survey and the South Pole Telescope, the analysis involved more than 150 researchers and is published as a set of three articles Jan. 31 in Physical Review D.

Among other findings, the analysis indicates that matter is not as "clumpy" as we would expect based on our current best model of the universe, which adds to a body of evidence that there may be something missing from our existing standard model of the universe.

Combining two different methods of looking at the sky reduces the chance that the results are thrown off by an error in one of the forms of measurement. "It functions like a cross-check, so it becomes a much more robust measurement than if you just used one or the other. In both cases, the analysis looked at a phenomenon called "gravitational lensing." As light travels across the universe, it can be slightly bent as it passes objects with lots of gravity, like galaxies.

This method catches both regular matter and dark matter—the mysterious form of matter that we have only detected due to its effects on regular matter—because both regular and dark matter exert gravity.
By rigorously analyzing these two sets of data, the scientists could infer where all the matter ended up in the universe. It is more precise than previous measurements—that is, it narrows down the possibilities for where this matter wound up—compared to previous analyses.
Part 1

Comment by Dr. Krishna Kumari Challa on February 1, 2023 at 9:04am

Scientists couple terahertz radiation with spin waves

An international research team has developed a new method for the efficient coupling of terahertz waves with much shorter wavelengths, so-called spin waves. As the experts report in the journal Nature Physics, their experiments, in combination with theoretical models, clarify the fundamental mechanisms of this process previously thought impossible. The results are an important step for the development of novel, energy-saving spin-based technologies for data processing.

Ruslan Salikhov et al, Coupling of terahertz light with nanometre-wavelength magnon modes via spin–orbit torque, Nature Physics (2023). DOI: 10.1038/s41567-022-01908-1

Comment by Dr. Krishna Kumari Challa on January 31, 2023 at 11:48am

Voles fall in love, even without oxytocin

Gene-edited prairie voles that can’t detect the ‘love hormone’ oxytocin still form monogamous relationships and care for their pups. The study challenges decades of research suggesting that prairie vo.... The study might help scientists to understand oxytocin’s role in humans. It has been trialled as a treatment for conditions that can affect social attachment. “There’s a sort of eerie similarity between prairie vole social behaviours and human social behaviours,” says neuroscientist Nirao Shah. “Prairie voles are one of the few mammalian species that exhibit social attachment.”

https://www.nature.com/articles/d41586-023-00197-9?utm_source=Natur...

Berendzen, K. M. et al. Neuron https://doi.org/10.1016/j.neuron.2022.12.011 (2023)

Comment by Dr. Krishna Kumari Challa on January 31, 2023 at 10:39am

Why do the cores of stars spin more slowly than expected?

Under certain conditions, the cores of stars contract. When this happens, they start to spin faster than the external layers of the star. However, the study of oscillations in stars, asteroseismology, has uncovered an astonishing phenomenon: The cores of such stars actually rotate more slowly than calculations predict. Why is this so?

Three  scientists from CNRS, INRIA and ENS-PSL have studied this question and report their findings in an article published in Science on January 19, 2023. Their numerical stimulations, which model plasma flow in the deep layers of a star, have shown that the slowing down of the core can be produced by an internal magnetic field. More specifically, plasma flow can amplify a magnetic field to the point where it generates strong turbulent motions. Such turbulence may further amplify the magnetic field until it causes the star's core to spin down.

The results obtained with the research team's simulations are also in agreement with asteroseismological observations of many stars. In addition, the simulations show that the magnetic field would be hidden by the outer layers of the star, which explains why no magnetic field of this kind has yet been measured with current techniques.

More information: Ludovic Petitdemange et al, Spin-down by dynamo action in simulated radiative stellar layers, Science (2023). DOI: 10.1126/science.abk2169

Comment by Dr. Krishna Kumari Challa on January 31, 2023 at 10:33am

The cognitive effects of air pollution- Even chess experts perform worse when air quality is lower, suggesting a negative effect on cognition

Here's something else chess players need to keep in check: air pollution.

That's the bottom line of a newly published study co-authored by an MIT researcher, showing that chess players perform objectively worse and make more suboptimal moves, as measured by a computerized analysis of their games, when there is more fine particulate matter in the air.

Fine particulate matter refers to tiny particles 2.5 microns or less in diameter, notated as PM_2.5. They are often associated with burning matter—whether through internal combustion engines in autos, coal-fired power plants, forest fires, indoor cooking through open fires, and more. The World Health Organization estimates that air pollution leads to over 4 million premature deaths worldwide every year, due to cancer, cardiovascular problems, and other illnesses.

More specifically, given a modest increase in fine particulate matter, the probability that chess players will make an error increases by 2.1 percentage points, and the magnitude of those errors increases by 10.8%. In this setting, at least, cleaner air leads to clearer heads and sharper thinking.

When individuals are exposed to higher levels of air pollution, they make more more mistakes, and they make larger mistakes, this study finds. Moreover, air pollution may affect people in settings where they might not think it makes a difference. It's not like you have to live next to a power plant. You can live miles away and be affected.

And while the focus of this particular study is tightly focused on chess players, the authors write in the paper that the findings have "strong implications for high-skilled office workers," who might also be faced with tricky cognitive tasks in conditions of variable air pollution. 

Steffen Künn et al, Indoor Air Quality and Strategic Decision Making, Management Science (2023). DOI: 10.1287/mnsc.2022.4643

Comment by Dr. Krishna Kumari Challa on January 31, 2023 at 10:19am

The model could be used for a virtual patient trial, allowing researchers to generate dozens of patients and then predict which ones would have hyper- or hypokalemia based on different controls.

"A lot of our models are pieces of a bigger picture," said Anita Layton, professor of applied mathematics and Canada 150 Research Chair in mathematical biology and medicine. "This model is one new and exciting piece in helping us understand how our incredibly complex internal systems work."

The model is especially exciting because it allows scientists to test something called the muscle-kidney cross-talk signal hypothesis. Scientists have hypothesized that skeletal muscles, which are responsible for most of the potassium storage in the body, can directly signal to the kidneys that it's time to excrete excess when too much potassium is stored, and vice versa. When the math researchers tested the hypothesis in their model, it more accurately reflected existing biological data regarding potassium homeostasis, suggesting that muscle-kidney cross talk might be an essential piece in the puzzle of potassium regulation.

The study was published in PLOS Computational Biology.

More information: Melissa M. Stadt et al, A mathematical model of potassium homeostasis: Effect of feedforward and feedback controls, PLOS Computational Biology (2022). DOI: 10.1371/journal.pcbi.1010607

Part 2

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Comment by Dr. Krishna Kumari Challa on January 31, 2023 at 10:18am

 Muscle-kidney cross talk might be an essential piece in the puzzle of potassium regulation.

Having levels of potassium that are too high or too low can be fatal. A new mathematical model sheds light on the often mysterious ways the body regulates this important electrolyte. Potassium, a common mineral abundant in food like bananas and leafy greens, is essential to normal cellular function. It helps the cardiac muscle work correctly and aids in the transmission of electrical signals within cells.

Using existing biological data, researchers built a mathematical model that simulates how an average person's body regulates potassium, both in times of potassium depletion and during potassium intake. Because so many foods contain abundant potassium, our bodies constantly store, deploy, and dispose of potassium to maintain healthy levels—a process known as maintaining potassium homeostasis. Understanding potassium homeostasis is essential in helping diagnose the source of the problem when something goes wrong—for example, when kidney disease or medication leads to dysregulation.
Too much potassium in the body, or hyperkalemia, can be just as dangerous as hypokalemia, or too little. Dysregulation of potassium can lead to dangerous and potentially fatal consequences.
Part 1

Comment by Dr. Krishna Kumari Challa on January 31, 2023 at 9:46am

A fairy-like robot flies by the power of wind and light

The development of stimuli-responsive polymers has brought about a wealth of material-related opportunities for next-generation small-scale, wirelessly controlled soft-bodied robots. For some time now, engineers have known how to use these materials to make small robots that can walk, swim and jump. 

Researchers are now trying how to make smart material fly. They have come up with a new design for their project called FAIRY—Flying Aero-robots based on Light Responsive Materials Assembly. They have developed a polymer-assembly robot that flies by wind and is controlled by light.

The artificial fairy developed by them has several biomimetic features. Because of its high porosity (0.95) and lightweight (1.2 mg) structure, it can easily float in the air directed by the wind. What is more, a stable separated vortex ring generation enables long-distance wind-assisted traveling. The fairy can be powered and controlled by a light source, such as a laser bean or LED.

This means that light can be used to change the shape of the tiny dandelion seed-like structure. The fairy can adapt manually to wind direction and force by changing its shape. A light beam can also be used to control the take-off and landing actions of the polymer assembly.

Jianfeng Yang et al, Dandelion‐Inspired, Wind‐Dispersed Polymer‐Assembly Controlled by Light, Advanced Science (2022). DOI: 10.1002/advs.202206752

Comment by Dr. Krishna Kumari Challa on January 30, 2023 at 10:00am

Study of 500,000 Medical Records Links Viruses to Alzheimer's Again And Again

A study of around 500,000 medical records has suggested that severe viral infections like encephalitis and pneumonia increase the risk of neurodegenerative diseases like Parkinson's and Alzheimer's.

Researchers found 22 connections between viral infections and neurodegenerative conditions in the study of around 450,000 people.

People treated for a type of inflammation of the brain called viral encephalitis were 31 times more likely to develop Alzheimer's disease. (For every 406 viral encephalitis cases, 24 went on to develop Alzheimer's disease – around 6 percent.)

Those who were hospitalized with pneumonia after catching the flu seemed to be more susceptible to Alzheimer's disease, dementia, Parkinson's disease, and amyotrophic lateral sclerosis (ALS).

Intestinal infections and meningitis (both often caused by a virus), as well as the varicella-zoster virus, which causes shingles, were also implicated in the development of several neurodegenerative diseases.

The impact of viral infections on the brain persisted for up to 15 years in some cases. And there were no instances where exposure to viruses was protective.

Around 80 percent of the viruses implicated in brain diseases were considered 'neurotrophic', which means they could cross the blood-brain barrier.

"Strikingly, vaccines are currently available for some of these viruses, including influenza, shingles (varicella-zoster), and pneumonia," the researchers write.

"Although vaccines do not prevent all cases of illness, they are known to dramatically reduce hospitalization rates. This evidence suggests that vaccination may mitigate some risk of developing neurodegenerative disease.

https://www.cell.com/neuron/fulltext/S0896-6273(22)01147-3?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0896627322011473%3Fshowall%3Dtrue

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