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Comment by Dr. Krishna Kumari Challa on September 26, 2020 at 6:59am

The male Y chromosome does more than we thought

New light is being shed on a little-known role of Y chromosome genes, specific to males, that could explain why men suffer differently than women from various diseases, including COVID-19. This  discovery provides a better understanding of how male genes on the Y chromosome allow male cells to function differently from female cells. These results could help to shed some light on why some diseases occur differently in men and women.

Humans each have 23 pairs of chromosomes, including one pair of sex chromosomes. While females carry two X sex chromosomes, males carry one X and one Y chromosome. This male chromosome carries genes that females lack. Although these male genes are expressed in all cells of the body, their only confirmed role to date has been essentially limited to the functions of the sex organs.

In his study, scientists performed a genetic manipulation that inactivated two male genes on the Y chromosome, altering several signalling pathways that play important roles in certain functions of non-sex organ cells. For example, under stress, some of the affected mechanisms could influence the way in which cells in human hearts defend themselves against aggressions such as ischemia (reduced blood supply) or mechanical stress.

In addition, the study showed that these male genes performed their regulatory functions in a way that was unusual compared to the mechanisms generally used by most other genes on the non-sex chromosomes. Thus, instead of specifically activating certain genes by direct action at the genome level, the Y chromosome seems to affect cellular functions by acting on protein production.

The discovery of these differences in function may explain in part why the functions of male Y chromosome genes have so far been poorly understood.

Males differ from females in the manifestation, severity and consequences of most diseases. A recent example of this duality is COVID-19, which has a mortality rate twice as high in men than in women.

Christian F. Deschepper, Regulatory effects of the Uty/Ddx3y locus on neighboring chromosome Y genes and autosomal mRNA transcripts in adult mouse non-reproductive cells, Scientific Reports (2020). DOI: 10.1038/s41598-020-71447-3

https://phys.org/news/2020-09-male-chromosome-thought.html?utm_sour...

Comment by Dr. Krishna Kumari Challa on September 26, 2020 at 6:57am

Research challenges conventional wisdom about key autism trait

https://medicalxpress.com/news/2020-09-conventional-wisdom-key-auti...

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Scientists capture light in a polymeric quasicrystal

https://phys.org/news/2020-09-scientists-capture-polymeric-quasicry...

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https://www.sciencemag.org/news/2020/09/how-neanderthals-lost-their...

How Neanderthals lost their Y chromosome

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Can fitness bands predict COVID-19 infection before you show symptoms? Probably not

WHOOP’s wearables make strong claims — but the science is still weak

https://massivesci.com/articles/whoop-wearable-fitness-tracker-covi...

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How microbes in a mother's intestines affect fetal neurodevelopment

https://researchnews.cc/news/2691/How-microbes-in-a-mother-s-intest...

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Dogs Deployed at Airport Can Detect COVID-19

https://www.sciencealert.com/dogs-deployed-at-helsinki-airport-can-...

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 The Massive 'Blob' Anomaly Has Our Fingerprints All Over It, Study Finds

https://www.sciencealert.com/the-foreboding-pacific-blob-anomaly-ha...

Comment by Dr. Krishna Kumari Challa on September 26, 2020 at 6:39am

Materials scientists learn how to make liquid crystal shape-shift

A new 3-D-printing method will make it easier to manufacture and control the shape of soft robots, artificial muscles and wearable devices.  Researchers show that by controlling the printing temperature of liquid crystal elastomer, or LCE, they can control the material's degree of stiffness and ability to contract—also known as degree of actuation. What's more, they are able to change the stiffness of different areas in the same material by exposing it to heat.

As a proof of concept, the researchers 3-D-printed in a single print, with a single ink, structures whose stiffness and actuation varies by orders of magnitude, from zero to 30 percent. For example, one area of the LCE structure can contract like muscles; and another can be flexible, like tendons. The breakthrough was possible because the team studied LCE closely to better understand its material properties.

 "Three-dimensional printing of functionally graded liquid crystal elastomer" Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.abc0034

https://phys.org/news/2020-09-materials-scientists-liquid-crystal-s...

Comment by Dr. Krishna Kumari Challa on September 26, 2020 at 6:34am

Machine learning takes on synthetic biology: algorithms can bioengineer cells for you

Conventional methods of bioengineering are slow and laborious, with trial and error being the main approach.

So now scientists have developed a new tool that adapts machine learning algorithms to the needs of synthetic biology to guide development systematically. The innovation means scientists will not have to spend years developing a meticulous understanding of each part of a cell and what it does in order to manipulate it; instead, with a limited set of training data, the algorithms are able to predict how changes in a cell's DNA or biochemistry will affect its behaviour, then make recommendations for the next engineering cycle along with probabilistic predictions for attaining the desired goal. According to the developers of this technology, if you're able to create new cells to specification in a couple weeks or months instead of years, you could really revolutionize what you can do with bioengineering.

Nature Communications (2020). DOI: 10.1038/s41467-020-18008-4

https://phys.org/news/2020-09-machine-synthetic-biology-algorithms-...

Comment by Dr. Krishna Kumari Challa on September 26, 2020 at 6:20am

Using deep learning to control the unconsciousness level of patients in an anesthetic state

Researchers have been developing machine learning algorithms for an increasingly wide range of purposes. This includes algorithms that can be applied in healthcare settings, for instance helping clinicians to diagnose specific diseases or neuropsychiatric disorders or monitor the health of patients over time.

They have recently carried out a study investigating the possibility of using deep reinforcement learning to control the levels of unconsciousness of patients who require anesthesia for a medical procedure. They  made significant progress in understanding how anesthetic medications affect neural activity  and now  a multidisciplinary team is studying how to accurately determine anesthetic doses from neural recordings. They also we trained a neural network using the cross-entropy method, by repeatedly letting it run on simulated patients and encouraging actions that led to good outcomes.  developed a deep neural network and trained it to control anesthetic dosing using reinforcement learning within a simulated environment. 

Controlling level of unconsciousness by titrating Propofol with deep reinforcement learning. arXiv:2008.12333 [cs.LG]. arxiv.org/abs/2008.12333

https://techxplore.com/news/2020-09-deep-unconsciousness-patients-a...

Comment by Dr. Krishna Kumari Challa on September 25, 2020 at 8:18am

How to embrace your scientific artistry Illustrations can help to get your research the attention it so richly deserves. Three scientific artists offer their advice about how to get started with the right tools, find inspiration and creat.... “One common issue at my zoological illustration and painting workshops is that scientists feel that they are not artistic enough — and artists feel that they are not scientific enough,” says illustrator Justine Hirten. “I encourage my students to accept themselves as legitimate members of both the creative and the scientific communities.”

Comment by Dr. Krishna Kumari Challa on September 25, 2020 at 7:48am

Lab uncovers new mechanism of action against SARS-CoV-2 by antiviral drug remdesivir

Researchers  have discovered a novel, second mechanism of action by the antiviral drug remdesivir against SARS-CoV-2

The research team previously demonstrated how remdesivir inhibits the COVID-19 virus's polymerase or replication machinery in a test tube.

Remdesivir stops or heavily delays replication of the virus, which in turn reduces propagation and spread.

 It is not common for antiviral drugs to have more than one mechanism of action. The first mechanism his team uncovered affects what is known as the "primer strand" of RNA or the first copy the virus makes of the viral genome as it infects a cell. The second mechanism affects the "template strand" which is repeated over and over as the virus spreads.

Egor P Tchesnokov et al, Template-dependent inhibition of coronavirus RNA-dependent RNA polymerase by remdesivir reveals a second mechanism of action, Journal of Biological Chemistry (2020). DOI: 10.1074/jbc.AC120.015720

https://phys.org/news/2020-09-lab-uncovers-mechanism-action-sars-co...

Comment by Dr. Krishna Kumari Challa on September 25, 2020 at 6:01am

Air pollution leads to increase in electricity usage, study suggests

High levels of air pollution are forcing people inside to consume more electricity, subsequently causing even greater environmental problems by increasing greenhouse gas emissions.

Pan He et al, Increase in domestic electricity consumption from particulate air pollution, Nature Energy (2020). DOI: 10.1038/s41560-020-00699-0

https://phys.org/news/2020-09-air-pollution-electricity-usage.html?...

Comment by Dr. Krishna Kumari Challa on September 25, 2020 at 5:58am

Gravity causes homogeneity of the universe

Gravity can accelerate the homogenization of space-time as the universe evolves. 

The temporal evolution of the universe, from the Big Bang to the present, is described by Einstein's field equations of general relativity. However, there are still a number of open questions about cosmological dynamics, whose origins lie in supposed discrepancies between theory and observation. One of these open questions is: Why is the universe in its present state so homogeneous on large scales?

It is assumed that the universe was in an extreme state shortly after the Big Bang, characterized in particular by strong fluctuations in the curvature of spacetime. During the long process of expansion, the universe then evolved towards its present state, which is homogeneous and isotropic on large scales—in simple terms: the cosmos looks the same everywhere.

This is inferred, among other things, from the measurement of the so-called background radiation, which appears highly uniform in every direction of observation. This homogeneity is surprising in that even two regions of the universe that were causally decoupled from each other—i.e., they could not exchange information—still exhibit identical values of background radiation.

To resolve this supposed contradiction, the so-called inflation theory was developed, which postulates a phase of extremely rapid expansion immediately after the Big Bang, which in turn can explain the homogeneity in the background radiation.

However, how this phase can be explained in the context of Einstein's theory requires a number of modifications of the theory, which seem artificial and cannot be verified directly.

In the concrete problem, the time evolution of the originally strong deviations from the homogeneous state as cosmological gravitational waves has to be analyzed mathematically. It has to be shown that they decay in the course of the expansion thus allowing the universe to get its homogeneous structure.

Such analyses are based on modern mathematical methods in the field of geometric analysis. Until now, these methods could only achieve such results for small deviations from the homogeneous space-time geometry. David Fajman from the University of Vienna has now succeeded for the first time to transfer these methods to the case of arbitrarily large deviations.

 David Fajman. Future Attractors in 2+1 Dimensional Λ Gravity, Physical Review Letters (2020). DOI: 10.1103/PhysRevLett.125.121102

https://phys.org/news/2020-09-gravity-homogeneity-universe.html?utm...

Comment by Dr. Krishna Kumari Challa on September 25, 2020 at 5:52am

Host-driven evolution: A new strategy of cell entry for some types of parvoviruses

Researchers  have discovered a new parvovirus strategy for reaching the cell nucleus, where they reproduce. The parvoviruses are extremely contagious and persistent in the environment. They are transmitted mainly through the feces of infected invertebrates, vertebrates and mammals including humans. To reach the nucleus of host cells, parvoviruses use mostly enzymatic reactions. They are first absorbed by the cell inside a vesicle, a membrane compartment. To escape, parvoviruses activate a viral enzyme domain called phospholipase A2 (PLA2), a key mechanism.

However, some types of parvoviruses, as well as other nonenveloped viruses, do not have this enzyme domain and must therefore escape from the vesicle by some other means. Using molecular biology and structural studies,  researchers have discovered that a new virus targeting the giant tiger shrimp uses a more mechanical response. This type of parvovirus contains an inner pentamer helix bundle held together by calcium ions. When the microorganism is in the vesicle, where the calcium concentration is decreased by the elimination of toxic substances, the bundle is released and opens up the protein shell (capsid) enclosing its genetic material and the membrane, allowing viral DNA to escape into the nucleus for replication.

Judit J. Pénzes et al, Molecular biology and structure of a novel penaeid shrimp densovirus elucidate convergent parvoviral host capsid evolution, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2008191117

https://phys.org/news/2020-09-strategy-cell-entry-parvoviruses.html...

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