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Comment by Dr. Krishna Kumari Challa on March 13, 2021 at 11:21am

Accurate aging of wild animals thanks to first epigenetic clock for bats

A new study  by  researchers found that DNA from tissue samples can be used to accurately predict the age of bats in the wild. The study also showed age-related changes to the DNA of long-lived species are different from those in short-lived species, especially in regions of the genome near genes associated with cancer and immunity. This work provides new insight into causes of age-related declines.

This is the first research paper to show that animals in the wild can be accurately aged using an epigenetic clock, which predicts age based on specific changes to DNA. This work provides a new tool for biologists studying animals in the wild. In addition, the results provide insight into possible mechanisms behind the exceptional longevity of many bat species. The study appears in the March 12, 2021, issue of the journal Nature Communications.

The researchers looked at DNA from 712 bats of known age, representing 26 species, to find changes in DNA methylation at sites in the genome known to be associated with aging. DNA methylation is a process that switches genes off. It occurs throughout development and is an important regulator for cells. Overall, methylation tends to decrease throughout the genome with age. Using machine learning to find patterns in the data, the researchers found that they could estimate a bat's age to within a year based on changes in methylation at 160 sites in the genome. The data also revealed that very long-lived bat species exhibit less change in methylation overall as they age than shorter-lived bats.

1. Gerald S. Wilkinson, Danielle M. Adams, Amin Haghani, Ake T. Lu, Joseph Zoller, Charles E. Breeze, Bryan D. Arnold, Hope C. Ball, Gerald G. Carter, Lisa Noelle Cooper, Dina K. N. Dechmann, Paolo Devanna, Nicolas J. Fasel, Alexander V. Galazyuk, Linus Günther, Edward Hurme, Gareth Jones, Mirjam Knörnschild, Ella Z. Lattenkamp, Caesar Z. Li, Frieder Mayer, Josephine A. Reinhardt, Rodrigo A. Medellin, Martina Nagy, Brian Pope, Megan L. Power, Roger D. Ransome, Emma C. Teeling, Sonja C. Vernes, Daniel Zamora-Mejías, Joshua Zhang, Paul A. Faure, Lucas J. Greville, Steve Horvath. DNA methylation predicts age and provides insight into exceptional longevity of bats. Nature Communications, 2021; 12 (1) DOI: 10.1038/s41467-021-21900-2

https://www.sciencedaily.com/releases/2021/03/210312095814.htm#:~:t....

https://phys.org/news/2021-03-accurate-aging-wild-animals-epigeneti...

Comment by Dr. Krishna Kumari Challa on March 13, 2021 at 10:11am

blackhole movement  - 2

We may be observing the aftermath of two supermassive black holes merging. The result of such a merger can cause the newborn black hole to recoil, and we may be watching it in the act of recoiling or as it settles down again.

But there's another, perhaps even more exciting possibility: the black hole may be part of a binary system.

Further observations, however, will ultimately be needed to pin down the true cause of this supermassive black hole's unusual motion.

Dominic W. Pesce et al, A Restless Supermassive Black Hole in the Galaxy J0437+2456, The Astrophysical Journal (2021). DOI: 10.3847/1538-4357/abde3d

https://phys.org/news/2021-03-astronomers-black-hole.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on March 13, 2021 at 10:09am

Astronomers detect a black hole on the move

Scientists have long theorized that supermassive black holes can wander through space—but catching them in the act has proven difficult. Now, researchers at the Center for Astrophysics | Harvard & Smithsonian have identified the clearest case to date of a supermassive black hole in motion. Their results are published today in the Astrophysical Journal.

We don't expect the majority of supermassive black holes to be moving; they're usually content to just sit around. They're just so heavy that it's tough to get them going. Consider how much more difficult it is to kick a bowling ball into motion than it is to kick a soccer ball—realizing that in this case, the 'bowling ball' is several million times the mass of our Sun. That's going to require a pretty mighty kick.

Usually the velocities of the black holes the same as the velocities of the galaxies they reside in. We expect them to have the same velocity. If they don't, that implies the black hole has been disturbed.

For their search, the team initially surveyed 10 distant galaxies and the supermassive black holes at their cores. They specifically studied black holes that contained water within their accretion disks—the spiral structures that spin inward towards the black hole.

As the water orbits around the black hole, it produces a laser-like beam of radio light known as a maser. When studied with a combined network of radio antennas using a technique known as very long baseline interferometry (VLBI), masers can help measure a black hole's velocity very precisely.

The technique helped the team determine that nine of the 10 supermassive black holes were at rest—but one stood out and seemed to be in motion.

Located 230 million light-years away from Earth, the black hole sits at the center of a galaxy named J0437+2456. Its mass is about three million times that of our Sun.

Using follow-up observations with the Arecibo and Gemini Observatories, the team has now confirmed their initial findings. The supermassive black hole is moving with a speed of about 110,000 miles per hour inside the galaxy J0437+2456.

But what's causing the motion is not known. The team suspects there are two possibilities.

Comment by Dr. Krishna Kumari Challa on March 13, 2021 at 9:16am

Three Ways Quantum Physics Affects Your Daily Life

Quantum physics is all around us. The universe as we know it runs on quantum rules, and while the classical physics that emerges when you apply quantum physics to enormously huge numbers of particles seem very different, there are lots of familiar, everyday phenomena that owe their existence to quantum effects. Here are a few examples of things you probably run into in your everyday life without realizing that they're quantum:

Toasters: The red glow of a heating element as you toast a slice of bread or a bagel is a very familiar sight for most of us. It's also the place where quantum physics got its start: Explaining why hot objects glow that particular color of red is the problem that quantum physics was invented to solve.

"quantum hypothesis" (giving the eventual theory its name) that the light could only be emitted in discrete chunks of energy, integer multiples of a small constant times the frequency of the light. For high-frequency light, this energy quantum is larger than the share of heat energy allotted to that frequency, and thus no light is emitted at that frequency. This cuts off the high-frequency light, and leads to a formula that matches the observed spectrum of light from hot objects to great precision.

So, every time you toast bread, you're looking at the place where quantum physics got its start.

Fluorescent Lights: Old-school incandescent light bulbs make light by getting a piece of wire hot enough to emit a bright white glow, which makes them quantum in the same way that a toaster is. If you have fluorescent bulbs around-- either the long tubes or the newer twisty CFL bulbs, you're getting light from another revolutionary quantum process.

Computers: While Bohr's quantum model was undeniably useful, it didn't initially come with a physical reason as to why there should be special states for electrons within atoms. That didn't come for almost ten years, but once the idea got locked it, it turned out to be the basis for the most transformative technological revolution of the last century.

So, every time you turn on your computer (say, to read a blog post about quantum physics), you're exploiting the wave nature of electrons, and the unprecedented control of materials that allows. It may not be the sexy kind of quantum computer, but every modern computer needs quantum physics to work properly.

https://www.forbes.com/sites/chadorzel/2018/12/04/three-ways-quantu...

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Comment by Dr. Krishna Kumari Challa on March 12, 2021 at 12:18pm

Comment by Dr. Krishna Kumari Challa on March 12, 2021 at 11:41am

I ain't afraid of no ghosts: people with mind-blindness not so easily spooked

People with aphantasia – that is, the inability to visualise mental images – are harder to spook with scary stories, a new UNSW Sydney study shows.

The study, published today in Proceedings of the Royal Society B, tested how aphantasic people reacted to reading distressing scenarios, like being chased by a shark, falling off a cliff, or being in a plane that’s about to crash.

The researchers were able to physically measure each participant’s fear response by monitoring changing skin conductivity levels – in other words, how much the story made a person sweat. This type of test is commonly used in psychology research to measure the body’s physical expression of emotion.

According to the findings, scary stories lost their fear factor when the readers couldn’t visually imagine the scene – suggesting imagery may have a closer link to emotions than scientists previously thought.

Researchers found the strongest evidence yet that mental imagery plays a key role in linking thoughts and emotions.

Aphantasia affects 2-5 per cent of the population, but there is still very little known about the condition.

A UNSW study published last year found that aphantasia is linked to a widespread pattern of changes to other cognitive processes, like remembering, dreaming and imagining.

https://royalsocietypublishing.org/doi/10.1098/rspb.2021.0267

https://researchnews.cc/news/5578/I-ain-t-afraid-of-no-ghosts--peop...

Comment by Dr. Krishna Kumari Challa on March 12, 2021 at 11:37am

Sonolithography: In‐Air Ultrasonic Particulate and Droplet Patterning

Sonolithography is based on the application of acoustic radiation forces arising from the interference of ultrasonic standing waves to direct airborne particle/droplet accumulation. Sonolithography is capable of rapidly patterning micrometer to millimeter scale materials onto a wide variety of substrates over a macroscale (cm2) surface area and can be used for both indirect and direct cell patterning.

Comment by Dr. Krishna Kumari Challa on March 12, 2021 at 11:31am

Membrane around tumors may be key to preventing metastasis

For cancer cells to metastasize, they must first break free of a tumor’s own defenses. Most tumors are sheathed in a protective “basement” membrane — a thin, pliable film that holds cancer cells in place as they grow and divide. Before spreading to other parts of the body, the cells must breach the basement membrane, a material that itself has been tricky for scientists to characterize. Now MIT engineers have probed the basement membrane of breast cancer tumors and found that the seemingly delicate coating is as tough as plastic wrap, yet surprisingly elastic like a party balloon, able to inflate to twice its original size. But while a balloon becomes much easier to blow up after some initial effort, the team found that a basement membrane becomes stiffer as it expands. This stiff yet elastic quality may help basement membranes control how tumors grow. 

The fact that the membranes appear to stiffen as they expand suggests that they may restrain a tumor’s growth and potential to spread, or metastasize, at least to a certain extent.

The findings, published this week in the Proceedings of the National Academy of Sciences, may open a new route toward preventing tumor metastasis, which is the most common cause of cancer-related deaths.

Now scientists can think of ways to add new materials or drugs to further enhance this stiffening effect, and increase the toughness of the membrane to prevent cancer cells from breaking through

https://news.mit.edu/2021/membrane-tumors-metastasis-0308

Comment by Dr. Krishna Kumari Challa on March 12, 2021 at 11:25am

Antarctic detector spots cosmic antineutrino

A huge neutrino detector in the Antarctic ice sheet might have seen the first evidence of a rare neutrino-interaction process called the Glashow resonance.

The IceCube Neutrino Observatory, buried in the deep ice near the Amundsen–Scott South Pole Station, observes eye-wateringly powerful neutrinos produced by sources such as active galactic nuclei and supernovae. The observatory detected a shower of secondary particles that look likely to have been caused by a collision between an electron antineutrino travelling close to th.... If confirmed by more observations, the finding provides further confirmation of the standard model of particle physics, proves the existence of cosmic antineutrinos and opens the door to a better understanding of the wild stuff going on in the cosmos.

https://www.nature.com/articles/d41586-021-00486-1?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on March 12, 2021 at 11:15am

Physicists measure smallest gravitational field yet

Physicists in Austria have measured the gravitational field from the smallest ever object: a gold sphere with a diameter of just 2 mm. Carried out using a miniature torsion balance, the measurement paves the way to even more sensitive gravitational probes that could reveal gravity’s quantum nature.

The latest work, in contrast, uses a gold sphere with a mass of just 92 mg as its source. Markus Aspelmeyer and Tobias Westphal of the Institute for Quantum Optics and Quantum Information in Vienna and colleagues positioned this mass a few millimetres away from another tiny gold sphere with about the same mass located at one end of a 4 cm-long glass rod. The rod was suspended at its centre via a silica fibre, while a third sphere at the far end of the rod acted as a counterbalance.

Such “torsion balances” have been used for more than 200 years to make precise measurements of gravity. The idea is that the source mass pulls the near end of the bar towards itself, causing the suspending fibre or wire to rotate. By measuring this rotation and balancing it against the stiffness of the wire, the strength of the gravitational interaction can be calculated. The fact that the bar moves horizontally means it is less exposed to the far larger gravitational field of the Earth.

A major challenge with such experiments is screening out noise. Aspelmeyer and colleagues did this by placing the balance in a vacuum to limit acoustic and thermal interference, while also grounding the source mass and placing a Faraday shield between it and the test mass to reduce electromagnetic interactions. In addition, they mainly collected data at night to minimize ambient sources of gravity. This is important because the gravitational attraction of the source mass is equivalent to the pull of a person standing 2.5 m from the experiment or a Vienna tram 50 m away.

To generate signals above the remaining noise, the researchers used a bending piezoelectric device to cyclically move the source towards and away from the test mass. Doing this at a fixed frequency (12.7 mHz) allowed them to look for a corresponding variation in the rotation of the balance – which they measured by bouncing a laser beam off a mirror below the silica fibre.

After repeating this process hundreds of times over a 13.5-hour period and then converting the time-series data into a frequency spectrum, Aspelmeyer and colleagues identified two clear signals above the background. These were the principle oscillation at 12.7 mHz and, at 25.4 mHz, the second harmonic generated by the gravitational field’s nonlinear variation in space. As the researchers point out, both harmonics were well above the resonant frequency of the oscillating balance and below the frequencies of readout noise.

https://www.nature.com/articles/s41586-021-03250-7.epdf?sharing_tok...

https://physicsworld.com/a/physicists-measure-smallest-gravitationa...

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