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Comment by Dr. Krishna Kumari Challa on March 19, 2021 at 9:42am

Found in space: Complex carbon-based molecules

Much of the carbon in space is believed to exist in the form of large molecules called polycyclic aromatic hydrocarbons (PAHs). Since the 1980s, circumstantial evidence has indicated that these molecules are abundant in space, but they have not been directly observed.

Now, a team of researchers has identified two distinctive PAHs in a patch of space called the Taurus Molecular Cloud (TMC-1). PAHs were thought  to form efficiently only at high temperatures—on Earth, they occur as byproducts of burning fossil fuels, and they're also found in char marks on grilled food. But the interstellar cloud where the research team observed them has not yet started forming stars, and the temperature is about 10 degrees above absolute zero.

This discovery suggests that these molecules can form at much lower temperatures than expected, and it may lead scientists to rethink their assumptions about the role of PAH chemistry in the formation of stars and planets, the researchers say.

B.A. McGuire el al., "Detection of two interstellar polycyclic aromatic hydrocarbons via spectral matched filtering," Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abb7535

Ci Xue et al. Detection of Interstellar HC4NC and an Investigation of Isocyanopolyyne Chemistry under TMC-1 Conditions, The Astrophysical Journal (2020). iopscience.iop.org/article/10. … 847/2041-8213/aba631

Brett A. McGuire et al. Early Science from GOTHAM: Project Overview, Methods, and the Detection of Interstellar Propargyl Cyanide (HCCCH2CN) in TMC-1, The Astrophysical Journal (2020). iopscience.iop.org/article/10. … 847/2041-8213/aba632

Andrew M. Burkhardt et al. Ubiquitous aromatic carbon chemistry at the earliest stages of star formation, Nature Astronomy (2021). DOI: 10.1038/s41550-020-01253-4

https://phys.org/news/2021-03-space-complex-carbon-based-molecules....

Comment by Dr. Krishna Kumari Challa on March 19, 2021 at 8:58am

Neuroscientists identify brain circuit motifs that support short-term memory

Humans have the innate ability to store important information in their mind for short periods of time, a capability known as short-term memory. Over the past few decades, numerous neuroscientists have tried to understand how neural circuits store short-term memories, as this could lead to approaches to assist individuals whose memory is failing and help to devise memory enhancing interventions.

Researchers  have recently identified neural circuit motifs involved in how humans store short-term memories. Their findings, published in Nature Neuroscience, suggest that memory-related neural circuits contain recurrently connected modules that independently maintain selective and continuous activity.

Short-term memories are of approximately 10 seconds or so, for example, if you needed to remember a phone number while you looked for a pen to write the number. Individual neurons, however, are very forgetful, as they can only remember their inputs for about 10 milliseconds. It has been hypothesized that if two forgetful neurons were connected to each other, they could continuously remind each other of what they were supposed to remember so that the circuit can now hold information for many seconds.

It was found that neurons tended to be connected in clusters. This means that the circuit was composed of many independent clusters, or modules, that were each able to store short-term memories independently. 

Targeted photostimulation uncovers circuit motifs supporting short-term memory. Nature Neuroscience(2021). DOI: 10.1038/s41593-020-00776-3.

https://medicalxpress.com/news/2021-03-neuroscientists-brain-circui...

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 12:33pm

Why does DNA spontaneously mutate? Quantum physics might explain.

Quantum mechanics, which rules the world of the teensy-tiny, may help explain why genetic mutations spontaneously crop up in DNA as it makes copies of itself, a recent study suggests.

Quantum mechanics describes the strange rules that govern atoms and their subatomic components. When the rules of classical physics, which describe the big world, break down, quantum comes in to explain. In the case of DNA, classical physics offers one explanation for why changes can suddenly appear in a single rung of the spiraling ladder of DNA, resulting in what's called a point mutation.

In a recent study, published Jan. 29 in the journal Physical Chemistry Chemical Physics, researchers explore another explanation, showing that a quantum phenomenon called proton tunneling can cause point mutations by allowing positively charged protons in DNA to leap from place-to-place. This, in turn, can subtly change the hydrogen bridges that bind the two sides of DNA's double helix, which can lead to errors when it's time for DNA to make copies of itself. 

In particular, this subtle change can potentially cause misprints in the DNA sequence, where the wrong "letters" get paired together as the strand replicates, the study authors note. These letters, known as bases, usually pair up in a certain way: A to T and G to C. But proton tunneling could cause some bases to mix-and-match. 

https://pubs.rsc.org/en/content/articlelanding/2021/CP/D0CP05781A#!divAbstract

https://www.livescience.com/quantum-physics-dna-mutations.html

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 12:20pm

Cutting emissions: Microwave hot water boiler heating system

https://patents.google.com/patent/US6064047A/en

First microwave-powered home boiler could help cut emissions

‘Drop-in’ replacement for gas boilers may help tackle challenge of cutting emissions from home heating

https://www.theguardian.com/environment/2021/mar/16/first-microwave...

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 12:06pm

When religious leaders stand in a Q for the vaccine!

 

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The world’s largest vaccine maker, Serum Institute of India, is testing a new virus-like particle vaccine for COVID-19 made with technology licensed from the UK-based SpyBiotech.Credit: Reuters/Amit Dave

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 11:38am

The collective movement of nanorobots observed in vivo

Nanobots are machines whose components are at the nano-scale (one-millionth of a millimeter), and can be designed in such a way that they have the ability to move autonomously in fluids. Although they are still in the research and development phase, significant advances are being made toward the use of nanorobots in biomedicine. Their applications are varied, from the identification of tumor cells to the release of drugs in specific locations of the body. Nanorobots powered by catalytic enzymes are among the most promising systems because they are fully biocompatible and can make use of "fuels" already available in the body for their propulsion. However, understanding the collective behavior of these nanorobots is essential to advance towards their use in clinical practice.

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Technology to detect chemicals in fruit and vegetables

An ITMO Ph.D. student with her colleagues from Russia, Spain and Singapore has developed flexible sensing films based on silver nanoparticles that can be used to identify the presence of pesticide residue on the surface of agricultural produce in minutes. The research results were published in Nanoscale.

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 11:29am

New chemicals -2 

The researchers report that 55 of the 109 chemicals they tentatively identified appear not to have been previously reported in people:

• 1 is used as a pesticide (bis(2,2,6,6-tetramethylpiperidini-4-y) decanedioate)
• 2 are PFASs (methyl perfluoroundecanoate, most likely used in the manufacturing of non-stick cookware and waterproof fabrics; 2-perfluorodecyl ethanoic acid)
• 10 are used as plasticizers (e.g. Sumilizer GA 80—used in food packaging, paper plates, small appliances)
• 2 are used in cosmetics
• 4 are high production volume (HPV) chemicals
• 37 have little to no information about their sources or uses (e.g., 1-(1-Acetyl-2,2,6,6-tetramethylpiperidin-4-yl)-3-dodecylpyrrolidine-2,5-dione, used in manufacturing fragrances and paints—this chemical is so little known that there is currently no acronym—and (2R0-7-hydroxy-8-(2-hydroxyethyl)-5-methoxy-2-,3-dihydrochromen-4-one (Acronym: LL-D-253alpha), for which there is limited to no information about its uses or sources

http://ucsf.edu/news/2021/03/420061/ucsf-study-finds-evidence-55-ch...

https://phys.org/news/2021-03-evidence-chemicals-people.html?utm_so...

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 11:29am

Study finds evidence of 55 new chemicals in people

Scientists at UC San Francisco have detected 109 chemicals in a study of pregnant women, including 55 chemicals never before reported in people and 42 "mystery chemicals," whose sources and uses are unknown.

The chemicals most likely come from consumer products or other industrial sources. They were found both in the blood of pregnant women, as well as their newborn children, suggesting they are traveling through the mother's placenta.

The study will be published March 17, 2021, in Environmental Science & Technology.

These chemicals have probably been in people for quite some time, but our technology is now helping us to identify more of them

The scientific team used high-resolution mass spectrometry (HRMS) to identify man-made chemicals in people.

But, while these chemicals can be tentatively identified using chemical libraries, they need to be confirmed by comparing them to the pure chemicals produced by manufacturers that are known as "analytical standards." And manufacturers do not always make these available.

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 11:22am

As endangered birds lose their songs, they can't find mates

Male songbirds usually learn their tunes from adult mentors. But when aspiring crooners lack proper role models, they hit all the wrong notes—and have less success attracting mates.

For five years, ecologist Ross Crates has tracked the singing ability and breeding success of critically endangered regent honeyeaters. These distinctive black and yellow birds were once common across Australia, but habitat loss since the 1950s has shrunk their population to only about 300 or 400 wild birds today.

While male birds once formed large winter flocks, now they are sparsely distributed across the landscape, so many fly solo. That means fewer honeyeater mentors are nearby during young birds' impressionable first year.

Song learning in many birds is a process similar to humans learning languages—they learn by listening to other individuals. If you can't listen to other individuals, you don't know what you should be learning.

The researchers found that a significant portion of male birds appear to be learning tunes exclusively from other species they encounter. About 12% of male regent honeyeaters wind up producing mangled versions of songs typically sung by noisy friarbirds and black-faced cuckooshrikes, among other species.

In some species, such as mockingbirds, song mimicry adds flourish to love songs. But the female regent honeyeaters aren't impressed.

Unconventional male singers were less successful in wooing mates, the scientists found in research published Tuesday in the journal Proceedings of the Royal Society B. "We think the females are avoiding breeding and nesting with males that sing unusual songs.

For a population already on the brink of extinction, that's worrisome.

"This research suggests that the loss of a song language once the population reaches a very small size could accelerate their decline

It could be that female honeyeaters aren't even recognizing these unconventional singers as potential partners, and so they're not approaching them. Or it could be that they approach, "but then things go wrong if the males get courtship signals wrong."

Hit the wrong note - Loss of vocal culture and fitness costs in a critically endangered songbird, Proceedings of the Royal Society B (2021). rspb.royalsocietypublishing.or … .1098/rspb.2021.0225

https://phys.org/news/2021-03-honeyeaters-wrong-song.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 11:11am

Scientists create model of an early human embryo from skin cells

In a discovery that will revolutionize research into the causes of early miscarriage, infertility and the study of early human development—an international team of scientists led by Monash University in Melbourne, Australia has generated a model of a human embryo from skin cells.

The team, led by Professor Jose Polo, has successfully reprogrammed these fibroblasts or skin cells into a 3-dimensional cellular structure that is morphologically and molecularly similar to human blastocysts. Called iBlastoids, these can be used to model the biology of early human embryos in the laboratory.

The achievement is a significant breakthrough for the future study of early human development and infertility. To date, the only way to study these first days has been through the use of difficult to obtain, and scarce, blastocysts obtained from IVF procedures.

Modelling human blastocysts by reprogramming fibroblasts into iBlastoids, Nature (2021). DOI: 10.1038/s41586-021-03372-y

https://phys.org/news/2021-03-scientists-early-human-embryo-skin.ht...

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