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Comment by Dr. Krishna Kumari Challa on July 7, 2023 at 10:49am

One place to look for evidence of asymmetry is in the electron's electric dipole moment (eEDM). Electrons are made up of negative electric charge, and the eEDM indicates how evenly that charge is spread between the electron's north and south pole. Any measurement of eEDM above zero would confirm an asymmetry; the electron would be more egg-shaped than circular. But no one knows just how small that deviation may be.

Electrons are fundamental particles, and their symmetry tells us about the symmetry of the universe.

Physicists  recently set a record for precision measurement of eEDM, improving on previous measurements by a factor of 2.4. How precise is that? If an electron were the size of the Earth, their study found that any asymmetry that exists would be smaller than the radius of an atom. Making a measurement that precise is incredibly difficult.

The researchers looked at molecules of hafnium fluoride. If they applied a strong electric field to the molecules, non-round electrons would want to align with the field, shifting around inside the molecule. If they were round, then the electrons wouldn't budge. Using an ultraviolet laser, they stripped electrons off molecules, making a set of positively charged ions, and trapped them. Alternating the electromagnetic field around the trap, the molecules were forced to either align or not align with the field. Then the researchers used lasers to measure the energy levels of the two groups. If the levels were different between them, that would indicate that the electrons were asymmetrical.

Their experiment allowed them to have longer measurement times than past attempts, which gave them greater sensitivity. However, the group's measurements showed that the electrons didn't move energy levels, indicating that as best as we can presently measure, electrons are round.

this level of precision from a tabletop experiment is an achievement. It shows that expensive particle accelerators are not the only means of exploring these fundamental questions about the universe, and that there are a lot of avenues to try. And while the group didn't find asymmetry, its result will help the field keep looking for answers to the asymmetry of the early universe.

Tanya S. Roussy et al, An improved bound on the electron's electric dipole moment, Science (2023). DOI: 10.1126/science.adg4084

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Comment by Dr. Krishna Kumari Challa on July 7, 2023 at 10:45am

Why does matter exist? Roundness of electrons may hold clues

In the first moments of our universe, countless numbers of protons, neutrons and electrons formed alongside their antimatter counterparts. As the universe expanded and cooled, almost all these matter and antimatter particles met and annihilated each other, leaving only photons, or flashes of light, in their wake.

And if the universe were perfectly symmetrical, with equal amounts of matter and antimatter, that would be the end of the story—and we would never have existed. But there must have been an imbalance—some leftover protons, neutrons and electrons—that formed atoms, molecules, stars, planets, galaxies and eventually, people.

If the universe had been perfectly symmetrical, then there would be nothing left but light. This is a hugely important moment in history. Suddenly there is stuff in the universe, and the question is, why? Why do we have this asymmetry?

The mathematical theories and equations that explain our universe call for symmetry. Particle theorists have refined these theories to tackle the presence of asymmetry. But without evidence, those theories are just math. So experimental physicists  have been looking at fundamental particles such as electrons for signs of asymmetry. Now they made a record-breaking measurement of electrons, narrowing down the search for where this asymmetry came from. The findings have been published in Science.

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Comment by Dr. Krishna Kumari Challa on July 6, 2023 at 12:47pm

How do fireworks actually work?

Comment by Dr. Krishna Kumari Challa on July 6, 2023 at 12:45pm

Use It or Lose It
As we age, the overall number of muscle cells declines: Studies suggest that muscle mass decreases by about 3 to 8 percent per decade after age 30 and at higher rates after age 60. Loss of muscular function and other factors also degrade the connection between motor nerves in the brain and muscle tissue. Issues in communication between nerves and muscles can create weakness and a decline in muscle mass. Experts recommend so-called high-velocity resistance training to keep the muscles ready to respond and the brain-muscle connection sharp.

Why this matters: Muscle loss is a common contributor to severe falls and accidents that lead to injury or physical disability in older adults. Low muscle mass from aging can impact how well individuals cope with cancer treatment, surgeries and heart and lung problems. It can impact individual lifespan and how quickly one recovers from illness and hospital stays.

What the experts say: Even if people don’t notice muscle mass gains through resistance training at first, “you actually get stronger long before your muscles get bigger,” says Stephanie Studenski, a geriatrician and professor emeritus at the University of Pittsburgh. “That exercise is doing something to the wiring to the nervous system connection to the muscle.”

Experts recommend so-called high-velocity resistance training to ke....

Comment by Dr. Krishna Kumari Challa on July 6, 2023 at 12:31pm

Why some people get sick more often

One reason why some people are more susceptible to falling ill than others is their body's response to inflammation. “We all need some inflammation, but it has to be the right amount at the right place at the right time,” says physician-scientist Sunil Ahuja. Ahuja and his colleagues found that some people’s immune systems are better at bouncing back from infec... that trigger inflammation. There’s no sure way to predict how you’ll weather any particular bout of disease, but Ahuja recommends reducing exposure risks (by wearing a protective mask, for example) and — this won’t surprise you — enjoying a healthy diet and plenty of exercise.

Scientific American | 6 min read
Reference: Nature Communications paper

Comment by Dr. Krishna Kumari Challa on July 6, 2023 at 12:14pm

New radio observations confirm unintended electromagnetic radiation...

Scientists from a number of leading research institutions including the Max Planck Institute for Radio Astronomy in Bonn, Germany, used the Low Frequency Array (LOFAR) telescope to observe 68 of SpaceX's satellites. The authors conclude that they detected "unintended electromagnetic radiation" emanating from onboard electronics.

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Facial recognition technology could soon be everywhere—here's how t...

The recent coronation of King Charles III was a high-profile example of when facial recognition technology has been used to monitor a crowd, but there are plenty of others. The technology is used by law enforcement all over the UK and other countries.

Comment by Dr. Krishna Kumari Challa on July 6, 2023 at 12:12pm

Study shows the Earth formed from dry, rocky building blocks

Billions of years ago, in the giant disk of dust, gas, and rocky material that orbited our young sun, larger and larger bodies coalesced to eventually give rise to the planets, moons, and asteroids we see today.

Scientists are still trying to understand the processes by which planets, including our home planet, were formed. One way researchers can study how Earth formed is to examine the magmas that flow up from deep within the planet's interior. The chemical signatures from these samples contain a record of the timing and the nature of the materials that came together to form Earth—analogous to how fossils give us clues about Earth's biological past.

Now, a study  shows that the early Earth accreted from hot and dry materials, indicating that our planet's water—the crucial component for the evolution of life—must have arrived late in the history of Earth's formation.

Though humans do not have a way to journey into the interior of our planet, the rocks deep within the earth can naturally make their way to the surface in the form of lavas. The parental magmas of these lavas can originate from different depths within Earth, such as the upper mantle, which begins around 15 kilometers under the surface and extends for about 680 kilometers; or the lower mantle, which spans from a depth of 680 kilometers all the way to the core–mantle boundary at about 2,900 kilometers below our feet.

Like sampling different layers of a cake—the frosting, the filling, the sponge—scientists can study magmas originating from different depths to understand the different "flavors" of Earth's layers: the chemicals found within and their ratios with respect to one another.

Because the formation of Earth was not instantaneous and instead involved materials accreting over time, samples from the lower mantle and upper mantle give different clues to what was happening over time during Earth's accretion.

In the new study, the team found that the early Earth was primarily composed of dry, rocky materials: chemical signatures from deep within the planet showed a lack of so-called volatiles, which are easily evaporated materials like water and iodine. In contrast, samples of the upper mantle revealed a higher proportion of volatiles, three times of those found in the lower mantle.

Based on these chemical ratios, researchers created a model that showed Earth formed from hot, dry, rocky materials, and that a major addition of life-essential volatiles, including water, only occurred during the last 15% (or less) of Earth's formation.

Weiyi Liu, I/Pu reveals Earth mainly accreted from volatile-poor differentiated planetesimals, Science Advances (2023). DOI: 10.1126/sciadv.adg9213. www.science.org/doi/10.1126/sciadv.adg9213

Comment by Dr. Krishna Kumari Challa on July 6, 2023 at 12:04pm

Although M. mycoides JCVI-syn3B could grow and divide in laboratory conditions, researchers wanted to know how a minimal cell would respond to the forces of evolution over time, particularly given the limited raw materials upon which natural selection could operate as well as the uncharacterized input of new mutations.

"Everysingle gene in its genome is essential" with reference to M. mycoides JCVI-syn3B. "One could hypothesize that there is no wiggle room for mutations, which could constrain its potential to evolve."

The researchers established that M. mycoides JCVI-syn3B, in fact, has an exceptionally high mutation rate. They then grew it in the lab where it was allowed to evolve freely for 300 days, equivalent to 2,000 bacterial generations or about 40,000 years of human evolution.

The next step was to set up experiments to determine how the minimal cells that had evolved for 300 days performed in comparison to the original, non-minimal M. mycoides as well as to a strain of minimal cells that hadn't evolved for 300 days. In the comparison tests, the researchers put equal amounts of the strains being assessed together in a test tube. The strain better suited to its environment became the more common strain.

They found that the non-minimal version of the bacterium easily outcompeted the unevolved minimal version. The minimal bacterium that had evolved for 300 days, however, did much better, effectively recovering all of the fitness that it had lost due to genome  streamlining. The researchers identified the genes that changed the most during evolution. Some of these genes were involved in constructing the surface of the cell, while the functions of several others remain unknown.

Understanding how organisms with simplified genomes overcome evolutionary challenges has important implications for long-standing problems in biology—including the treatment of clinical pathogens, the persistence of host-associated endosymbionts, the refinement of engineered microorganisms, and the origin of life itself.

this demonstrates the power of natural selection to rapidly optimize fitness in the simplest autonomous organism, with implications for the evolution of cellular complexity. In other words, it shows that life finds a way.

Jay Lennon, Evolution of a minimal cell, Nature (2023). DOI: 10.1038/s41586-023-06288-x. www.nature.com/articles/s41586-023-06288-x

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Comment by Dr. Krishna Kumari Challa on July 6, 2023 at 12:01pm

Artificial cells demonstrate that 'life finds a way'

Evolutionary biologists  have been studying a synthetically constructed minimal cell that has been stripped of all but its essential genes. They found that the streamlined cell can evolve just as fast as a normal cell—demonstrating the capacity for organisms to adapt, even with an unnatural genome that would seemingly provide little flexibility.

This shows that if there's one thing the history of evolution has taught us is that life will not be contained. Life breaks free. It expands to new territories, and it crashes through barriers painfully, maybe even dangerously, but . . . life finds a way.

It appears there's something about life that's really robust. We can simplify it down to just the bare essentials, but that doesn't stop evolution from going to work.

For their study,  the researchers used the synthetic organism, Mycoplasma mycoides JCVI-syn3B—a minimized version of the bacterium M. mycoides commonly found in the guts of goats and similar animals. Over millennia, the parasitic bacterium has naturally lost many of its genes as it evolved to depend on its host for nutrition.

Researchers at the J. Craig Venter Institute in California took this one step further. In 2016, they eliminated 45% of the 901 genes from the natural M. mycoides genome—reducing it to the smallest set of genes required for autonomous cellular life. At 493 genes, the minimal genome of M. mycoides JCVI-syn3B is the smallest of any known free-living organism. In comparison, many animal and plant genomes contain more than 20,000 genes.

In principle, the simplest organism would have no functional redundancies and possess only the minimum number of genes essential for life. Any mutation in such an organism could lethally disrupt one or more cellular functions, placing constraints on evolution. Organisms with streamlined genomes have fewer targets upon which positive selection can act, thus limiting opportunities for adaptation.

Part 1

Comment by Dr. Krishna Kumari Challa on July 5, 2023 at 12:52pm

More work will be needed to determine whether the impact of climate change on Homo physiology is a result specifically of temperature changes or an indirect effect from other elements of a changing environment.

https://karger.com/bbe/article/98/2/93/835670/Climate-Change-Influe...

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