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Comment by Dr. Krishna Kumari Challa on May 2, 2021 at 12:14pm

In long-awaited breakthrough,  scientists harness molecules into single quantum state

 Researchers have big ideas for the potential of quantum technology, from unhackable networks to earthquake sensors. But all these things depend on a major technological feat: being able to build and control systems of quantum particles, which are among the smallest objects in the universe.

That goal is now a step closer with the publication of a new method by  scientists. Published April 28 in Nature, the paper shows how to bring multiple molecules at once into a single quantum state—one of the most important goals in quantum physics.

One of the essential states of matter is called a Bose-Einstein condensate: When a group of particles cooled to nearly absolute zero share a quantum state, the entire group starts behaving as though it were a single atom. It’s a bit like coaxing an entire band to march entirely in step while playing in tune—difficult to achieve, but when it happens, a whole new world of possibilities can open up.

Scientists have been able to do this with atoms for a few decades, but what they’d really like to do is to be able to do it with molecules. Such a breakthrough could serve as the underpinning for many forms of quantum technology.

But because molecules are larger than atoms and have many more moving parts, most attempts to harness them have dissolved into chaos. “Atoms are simple spherical objects, whereas molecules can vibrate, rotate, carry small magnets. Because molecules can do so many different things, it makes them more useful, and at the same time much harder to control.

So the scientists first  cooled the entire system down —down to 10 nanokelvins, a split hair above absolute zero. Then they packed the molecules into a crawl space so that they were pinned flat. Typically, molecules want to move in all directions, and if you allow that, they are much less stable. The researchers confined the molecules so that they are on a 2D surface and can only move in two directions.

The result was a set of virtually identical molecules—lined up with exactly the same orientation, the same vibrational frequency, in the same quantum state.

The scientists described this molecular condensate as like a pristine sheet of new drawing paper for quantum engineering. So far, they’ve been able to link up to a few thousand molecules together in such a state, and are beginning to explore its potential.

Zhang, Chen, Yao and Chin. Atomic Bose-Einstein condensate to molecular Bose-Einstein condensate transition. Nature, 2021 DOI: 10.1038/s41586-021-03443-0

Comment by Dr. Krishna Kumari Challa on May 1, 2021 at 10:34am

Retron Library Recombineering (RLR): New gene editing tool  

Researchers  have created a new gene editing tool called Retron Library Recombineering (RLR) that makes this task easier. RLR generates up to millions of mutations simultaneously, and "barcodes" mutant cells so that the entire pool can be screened at once, enabling massive amounts of data to be easily generated and analyzed. The achievement, which has been accomplished in bacterial cells, is described in a recent paper in PNAS.

 

RLR enabled scientists to do something that's impossible to do with CRISPR: they randomly chopped up a bacterial genome, turned those genetic fragments into single-stranded DNA in situ, and used them to screen millions of sequences simultaneously.

RLR is a simpler, more flexible gene editing tool that can be used for highly multiplexed experiments, which eliminates the toxicity often observed with CRISPR and improves researchers' ability to explore mutations at the genome level.

 Max G. Schubert et al. High-throughput functional variant screens via in vivo production of single-stranded DNA, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2018181118

https://phys.org/news/2021-04-crispr-retrons.html?utm_source=nwlett...

Comment by Dr. Krishna Kumari Challa on May 1, 2021 at 9:51am

Three new studies suggest Z-genome is much more widespread in bacte...

Three teams working independently have found evidence that suggests the Z-genome in bacteria-invading viruses is much more widespread than thought. All three of the groups have used a variety of genomic techniques to identify parts of the pathways that lead development of the Z-genome in bacteria-invading viruses known as bacteriophages. The first team was made up of researchers from several institutions in China and one in Singapore, the second with members from several institutions in France; the third was an international effort. All three teams have published their results in the journal Science. Michael Grome and Farren Isaacs with Yale University have also published a Perspectives piece in the same journal issue outlining the work of all three teams.

Comment by Dr. Krishna Kumari Challa on May 1, 2021 at 7:05am

The Evolution of Bacteria on a “Mega-Plate” Petri Dish

Comment by Dr. Krishna Kumari Challa on April 30, 2021 at 12:40pm

A clock’s accuracy may be tied to the entropy it creates

A clock made from a wiggling membrane produces more disorder as it becomes more accurate

Today’s most advanced clocks keep time with an incredibly precise rhythm. But a new experiment suggests that clocks’ precision comes at a price: entropy.

Entropy, or disorder, is created each time a clock ticks. Now, scientists have measured the entropy generated by a clock that can be run at varying levels of accuracy. The more accurate the clock’s ticks, the more entropy it emitted, physicists report in a paper accepted to Physical Review X.

https://www.sciencenews.org/article/clock-time-accuracy-entropy-dis...

Comment by Dr. Krishna Kumari Challa on April 30, 2021 at 12:02pm

These cellular clocks help explain why elephants are bigger than mice

Biologists are uncovering how tiny timekeepers in our cells might govern body size, lifespan and ageing.

Time keepers in our cells: Biologists are uncovering how tiny ‘clocks’ in our cells might help govern body size, lifespan and ageing. (Mouse cells seem to run faster than human cells, which tick faster than whale cells.) A wave of research is starting to yield answers for one such timepi.... It helps developing embryos to form repeating body segments, such as vertebrae. Researchers want to understand how differences in developmental pace give rise to organisms with such different bodies and behaviours.

Comment by Dr. Krishna Kumari Challa on April 30, 2021 at 11:59am

The Wave Beneath Their Wings

Researchers developed a theoretical model that describes how pelicans take advantage of wind updrafts generated by breaking waves to glide in a practice the scientists call wave-slope soaring.

Comment by Dr. Krishna Kumari Challa on April 30, 2021 at 11:57am

How SARS-CoV-2 hijacks human cells to evade immune system

Researchers at University of California San Diego School of Medicine have discovered one way in which SARS-CoV-2, the coronavirus that causes COVID-19, hijacks human cell machinery to blunt the immune response, allowing it to establish infection, replicate and cause disease. In short, the virus genome gets tagged with a special marker by a human enzyme that tells the immune system to stand down, while at the same time ramping up production of the surface proteins that SARS-CoV-2 uses as a doorknob to enter cells. The study, published April 22, 2021 in Cell Reports, helps lay the groundwork for new anti-viral immunotherapies  treatments that work by boosting a patients immune system, rather than directly killing the virus. Its very smart of this virus to use host machinery to simultaneously go into stealth mode and get inside more cells

Comment by Dr. Krishna Kumari Challa on April 30, 2021 at 11:28am

The mystery of sleep: Why can’t we stay awake indefinitely?

Comment by Dr. Krishna Kumari Challa on April 30, 2021 at 10:01am

Lightning may be an important source of air-cleaning chemicals

A storm-chasing airplane caught thunderstorms producing extremely high concentrations of two important oxidants

Lightning could play an important role in flushing pollutants out of the atmosphere.

Observations from a storm-chasing airplane reveal that lightning can forge lots of air-cleansing chemicals called oxidants, researchers report online April 29 in Science. Oxidants help clear the air by reacting with contaminants like methane to form molecules that are more water soluble or stickier, allowing them to more easily rain out of Earth’s atmosphere or stick to its surface.

Researchers knew lightning produces nitric oxide, which can lead to the formation of oxidants such as hydroxyl radicals. But no one had seen lightning directly create lots of these oxidants.

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In May and June 2012, a NASA jet measured two oxidants in storm clouds over Colorado, Oklahoma and Texas. One was the hydroxyl radical, OH. The other was a similar oxidant called the hydroperoxyl radical, HO₂. The combined concentration of OH and HO₂ molecules, generated by lightning and other electrified regions of air, reached up to thousands of parts per trillion in some parts of these clouds. The highest concentration of OH previously observed in the atmosphere was a few parts per trillion. The most HO₂ observed was about 150 parts per trillion.

https://www.sciencenews.org/article/lightning-storm-chemicals-air-c...

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