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All about Science - to remove misconceptions and encourage scientific temper

Communicating science to the common people

'To make  them see the world differently through the beautiful lense of  science'

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  • Dr. Krishna Kumari Challa

    **Aerodynamicists reveal link between fish scales and aircraft drag

    Reducing drag means faster aircraft speeds and less fuel consumption this is an important area of study for aerodynamicists

    Through their biomimetic study, Professor Bruecker's team has discovered that the fish-scale array produces a zig-zag motion of fluid in overlapping regions of the surface of the fish, which in turn causes periodic velocity modulation and a streaky flow that can eliminate Tollmien-Schlichting wave induced transition to reduce skin friction drag by more than 25 percent.

    An examination of oil flow visualization using computational fluid dynamics (CFD) on sea bass and common carp enabled the authors to come up with a working hypothesis:

    "Computation Fluid Dynamics (CFD) was used to study the flow pattern over the surface and revealed a hitherto unknown effect of the scales as a mechanism to generate a regular pattern of parallel streamwise velocity streaks in the boundary layer. To prove their existence also on the real fish skin, oil flow visualization was done on sea bass and common carp, which indeed confirmed their presence in a regular manner along their real body, with the same arrangement relative to the scale array as observed along the biomimetic surface. These results let the authors hypothesize about a possible mechanism for transition delay, inspired by various previous fundamental transition studies, where streaky structures generated by cylindrical roughness elements or vortex generator arrays have shown a delay of transition."

    Their surprising research outcome runs counter to the common belief that roughness promotes by-pass transition. Instead, the scales largely increase the stability of the base flow similar to an array of vortex generators.

    A technical realization of such patterns on aerodynamic surfaces will pave the way towards the drastic reduction in fuel consumption and future zero-emission flight.

    Muthukumar Muthuramalingam et al, Transition delay using biomimetic fish scale arrays, Scientific Reports (2020). DOI: 10.1038/s41598-020-71434-8

    Muthukumar Muthuramalingam et al. Streak formation in flow over biomimetic fish scale arrays, The Journal of Experimental Biology (2019). DOI: 10.1242/jeb.205963

    https://phys.org/news/2020-10-aerodynamicists-reveal-link-fish-scal...

  • Dr. Krishna Kumari Challa

    New research: nitrous oxide emissions 300 times more powerful than CO₂ are jeopardising Earth’s future

    Nitrous oxide from agriculture and other sources is accumulating in the atmosphere so quickly it puts Earth on track for a dangerous 3℃ warming this century,  new research has found.

    This colossal amount of nitrogen makes crops and pastures grow more abundantly. But it also releases nitrous oxide (N₂O), a greenhouse gas.

    The study found that N₂O emissions from natural sources, such as soils and oceans, have not changed much in recent decades. But emissions from human sources have increased rapidly.

    Agriculture caused almost 70% of global N₂O emissions in the decade to 2016. The emissions are created through microbial processes in soils. The use of nitrogen in synthetic fertilisers and manure is a key driver of this process.

    Other human sources of N₂O include the chemical industry, waste water and the burning of fossil fuels.

    https://theconversation.com/new-research-nitrous-oxide-emissions-30...

  • Dr. Krishna Kumari Challa

    https://www.sciencealert.com/a-bacterial-clone-is-behind-a-concerni...

    A Historical Epidemic Has Been Making a Scary Comeback Due to a Bacterial 'Clone'

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    Brain Cells Turned to Glass Found in a Victim of The Vesuvius Eruption

    Preserved brain cells have been found in the remains of a young man who died in the eruption of Mount Vesuvius in 79 CE. 

    The brain cells' structure is still visible in a black, glassy material found in the man's skull. The new discovery of this structure, described on October 2 in the journal PLOS One, adds to the accumulating evidence that this glassy material is indeed part of the man's brain.

    The transformation to glass occurred as a result of extreme heating and rapid cooling. 

    The results of the study show that the vitrification process occurred at Herculaneum, unique of its kind, has frozen the neuronal structures of this victim, preserving them intact until today

    https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0...

    https://www.sciencealert.com/brain-cells-turned-to-glass-have-been-...

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    2,500 y/o mummy in "perfect condition" revealed after discovery of 59 sarcophagi

    https://www.youtube.com/watch?v=7sd0BomMDDk&feature=emb_logo

  • Dr. Krishna Kumari Challa

    Neurobiology of conversation: Brain activity depends on who you're talking to

    Our brains respond differently when talking to a person from a different socioeconomic group than during a conversation with someone of a similar background, a novel new imaging study shows.

    While neuroscientists have used brain imaging scans to track in great detail neural responses of individuals to a host of factors such as stress, fear, addiction, and even love and lust, new research shows what happens in the brains of two individuals engaged in a simple social interaction.

    The study reveals the distinct neurobiology of a conversation between two people of different backgrounds.

    When a  professor talks to a homeless person, his or her frontal lobe activates a different neural network than if they were chatting with another colleague. Our brain has apparently designed a frontal lobe system that helps us deal with our diversity.

    The researchers found that in both subjects the activity in the left dorsolateral prefrontal cortex, which is involved in control of cognitive processes, was much higher when they talked with someone from a different socioeconomic background than with someone of similar status.

    There is a neurobiology of socialness, and neurobiology allows us to modulate our response to diversity.  We want to be inclusive, we want equity, and theoretically, neuroscience can say something about how we can achieve that.

    https://news.yale.edu/2020/10/05/neurobiology-conversation-brain-ac...

    https://researchnews.cc/news/2902/Neurobiology-of-conversation--Bra...

  • Dr. Krishna Kumari Challa

    Study Points to Novel Role for Microglia in Down Syndrome


    Overactive immune cells identified in a mouse model and in postmortem human brain tissue may offer a potential therapeutic target for cognitive delays associated with the condition, researchers report.

    Overactivation of the brain’s immune cells, called microglia, may play a role in cognitive impairments associated with Down syndrome.

    Researchers in Italy identified elevated numbers of the cells in an inflammation-promoting state in the brains of mice with a murine version of the syndrome as well as in postmortem brain tissue from people with the condition. The team additionally showed that drugs that reduce the number of activated microglia in juvenile mice could boost the animals’ performance on cognitive tests.

    https://www.cell.com/neuron/fulltext/S0896-6273(20)30710-8

    https://www.the-scientist.com/news-opinion/study-points-to-novel-ro...


  • Dr. Krishna Kumari Challa

    New method can pinpoint cracks in metal long before they cause catastrophes

    Fatigue failure plagues all metals and mitigating it is of great importance.

    It is the leading cause of cracks in metallic components of aircraft.

    That is why it is common practice in the airline industry to adhere to regular—and expensive—replacement schedules for many parts. But the life of those parts could be more accurately determined by better understanding the origins of crack initiation.

    Whether it is the pounding of vehicles on bridges or shifts in air pressure on airplanes, such continuous change called "cyclic loading" gradually induces slips in the internal molecular structure of the most durable metals until cracks occur that could have been anticipated long before their perilous appearance.

    With the lack of understanding of the mechanisms that lead to crack initiation, it has been difficult to predict with any reasonable accuracy the remaining life of a cyclically loaded material. The component could actually be fine and never fail but they throw it away anyway solely on the bases of statistical arguments. That's a huge waste of money.

    Most current tests to understand the origins of crack initiation have focused on the moments just prior to or after cracking to assess what happened in the makeup of the metal. And many of those tests use far larger samples that preclude tracking the initiation of damage, which is a sub-micrometer scale feature. The new method narrows the lens as small as feasible and begins when metals are first exposed to loads that lead to localized damage that could become cracks.

     "The heterogeneity of persistent slip band nucleation and evolution in metals at the micrometer scale" Science (2020). science.sciencemag.org/cgi/doi … 1126/science.abb2690

    https://phys.org/news/2020-10-method-metal-catastrophes.html?utm_so...

  • Dr. Krishna Kumari Challa

    Generating photons for communication in a quantum computing system

    Researchers using superconducting quantum bits connected to a microwave transmission line have shown how the qubits can generate on demand the photons, or particles of light, necessary for communication between quantum processors.

    The advance is an important step toward achieving the interconnections that would allow a modular quantum computing system to perform operations at rates exponentially faster than classical computers can achieve.

     B. Kannan et al. Generating spatially entangled itinerant photons with waveguide quantum electrodynamics, Science Advances (2020). DOI: 10.1126/sciadv.abb8780

    https://phys.org/news/2020-10-photons-quantum.html?utm_source=nwlet...

  • Dr. Krishna Kumari Challa

    **Duplications and inversions of DNA segments lead to the masculinization of female moles

    Female moles are intersexual while retaining their fertility. Typical for mammals, they are equipped with two X chromosomes, but they simultaneously develop functional ovarian and testicular tissues. In female moles, both tissue types are united in one organ, the ovotestis—a feature unique among mammals.

    The testicular tissue of the female mole does not produce sperm, but large amounts of the sex hormone testosterone, meaning the females have similarly high levels as the males. Presumably, this natural "doping" makes the female moles aggressive and muscular, an advantage for life underground, where they have to dig burrows and fight for resources.

    Scientists are now reporting on the genetic peculiarities that lead to this characteristic sexual development in moles. According to the study, it is primarily changes in the structure of the genome that lead to altered control of genetic activity. In addition to the genetic program for testicular development, this also stimulates enzymes for male hormone production in the females.

    the researchers have completely sequenced the genome of the Iberian mole (Talpa occidentalis) for the first time. Moreover, they examined the three-dimensional structure of the genome within the cell. In the nucleus, genes and their associated control sequences form regulatory domains—relatively isolated "neighborhoods" consisting of large regions where DNA sections interact frequently with each other.

    In the course of the moles' evolution, then not only would individual letters of the DNA have changed, also larger pieces of the genome would have shifted.

    If segments of DNA move from one location to another, completely new or reorganized regulatory domains can emerge and thus activate new genes and enhance or attenuate their expression.

    When comparing the genome to that of other animals and humans, the team discovered an inversion—i.e., an inverted genomic segment—in a region known to be involved in testicular development. The inversion causes additional DNA segments to get included in the regulatory domain of the gene FGF9, which reorganizes the control and regulation of the gene. "This change is associated with the development of testicular tissue in addition to ovarian tissue in female moles.

    The team also discovered a triplication of a genomic region responsible for the production of male sex hormones (androgens), more specifically the androgen production gene CYP17A1. "The triplication appends additional regulatory sequences to the gene—which ultimately leads to an increased production of male sex hormones in the ovotestes of female moles, especially more testosterone

     DOI: 10.1126/science.aaz2582 "The mole genome reveals regulatory rearrangements associated with adaptive intersexuality" Science (2020). science.sciencemag.org/cgi/doi … 1126/science.aaz2582

    https://phys.org/news/2020-10-duplications-inversions-dna-segments-...

  • Dr. Krishna Kumari Challa

    Ants adapt tool use to avoid drowning

    Researchers have observed black imported fire ants using sand to draw liquid food out of containers, when faced with the risk of drowning. This is the first time this sophisticated tool use has been reported in animals.

    Aiming Zhou et al, Ants adjust their tool use strategy in response to foraging risk, Functional Ecology (2020). DOI: 10.1111/1365-2435.13671

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    Nanoscale machines convert light into work

    Researchers have developed a tiny new machine that converts laser light into work. These optically powered machines self-assemble and could be used for nanoscale manipulation of tiny cargo for applications such as nanofluidics and particle sorting.

    The work addresses a long-standing goal in the nanoscience community to create self-assembling nanoscale machines that can perform work in conventional environments such as room temperature liquids.

    The machines are based on a type of matter known as optical matter in which metal nanoparticles are held together by light rather than the chemical bonds that hold together the atoms that make up typical matter.

    Both the energy for assembling the machine and the power to make it work come from light. Once the laser light is introduced to a solution containing nanoparticles, the entire process occurs on its own. Although the user does not need to actively control or direct the outcome, this could readily be done to tailor the machines for various applications.

    In optical matter, a laser light field creates interactions between metal nanoparticles that are much smaller than the wavelength of light. These interactions cause the particles to self-assemble into ordered arrays. This is a similar principle to optical trapping, in which light is used to hold and manipulate particles, biological molecules and cells.

    --

    In the new work, the researchers created an optical matter machine that operates much like a mechanical machine based on interlocking gears. In such machines, when one gear is turned, a smaller interlocking gear will spin in the opposite direction. The optical matter machine uses circularly polarized light from a laser to create a nanoparticle array that acts like the larger gear by spinning in the optical field. This "optical matter gear" converts the circularly polarized light into orbital, or angular, momentum that influences a nearby probe particle to orbit the nanoparticle array (the gear) in the opposite direction.

    --

    In previous work, the researchers discovered that when optical matter is exposed to circularly polarized light, it rotates as a rigid body in the direction opposite the polarization rotation. In other words, when the incident light  rotates one way the optical matter array responds by spinning the other. This is a manifestation of "negative torque". The researchers speculated that a machine could be developed based on this new phenomenon.

    John Parker et al, An Optical Matter Machine: Angular Momentum Conversion by Collective Modes in Optically Bound Nanoparticle Arrays, Optica (2020). DOI: 10.1364/OPTICA.396147

    https://phys.org/news/2020-10-nanoscale-machines.html?utm_source=nw...

  • Dr. Krishna Kumari Challa

    Human spatial memory prioritizes high calorie foods

    Humans more accurately recall the locations of high calorie than low calorie foods, according to a study . The findings suggest that human spatial memory, which allows people to remember where objects are in relation to each another, has evolved to prioritize the location of high calorie foods.

    The findings indicate that human spatial memory is biased towards locating high calorie foods. This bias could have helped human ancestors to survive in environments with fluctuating food availability by enabling them to efficiently locate calorie-dense foods through foraging.

    Human spatial memory implicitly prioritizes high-calorie foods, Scientific Reports (2020). DOI: 10.1038/s41598-020-72570-x , www.nature.com/articles/s41598-020-72570-x

    https://medicalxpress.com/news/2020-10-human-spatial-memory-priorit...

  • Dr. Krishna Kumari Challa

    **New model may explain rarity of certain malaria-blocking mutations

    A new computational model suggests that certain mutations that block infection by the most dangerous species of malaria have not become widespread in people because of the parasite's effects on the immune system.

    Several protective adaptations to malaria have spread widely among humans, such as the sickle-cell mutation. Laboratory experiments suggest that certain other mutations could be highly protective against the most dangerous human-infecting malaria species, Plasmodium falciparum. However, despite being otherwise benign, these mutations have not become widespread.

    To help clarify why some protective mutations may remain rare, Penman and colleagues developed a computational model that simulates the epidemiology of malaria infection, as well the evolution of protective mutations. Importantly, the model also incorporates mechanisms of adaptive immunity, in which the immune system "learns" to recognize and attack specific pathogens, such as P. falciparum.

    Analysis of the model's predictions suggests that if people rapidly gain adaptive immunity to the severe effects of P. falciparum malaria, mutations capable of blocking P. falciparum infection are unlikely to spread among the population. The fewer the number of infections it takes for people to become immune to the severe effects of malaria, the less likely it is that malaria infection-blocking mutaions will arise.

    understanding how humans have adapted to malaria could help open up new avenues for treatment.

     Penman BS, Gandon S (2020) Adaptive immunity selects against malaria infection blocking mutations. PLoS Comput Biol 16(10): e1008181. doi.org/10.1371/journal.pcbi.1008181

    https://phys.org/news/2020-10-rarity-malaria-blocking-mutations.htm...

  • Dr. Krishna Kumari Challa

    Thinning forests no defence against fires

    Having logging machines "thin" forest for fire reduction is largely ineffective, a new peer-reviewed, scientific study has found.

    The study compared fire severity in unthinned versus thinned forest burned in the 2009 wildfires. It covered two forest types-mixed species forest and ash forest.

    The scientific evidence showed that across almost every forest age and type, thinning made little difference. It actually increased the likelihood of a crown burn in older, mixed species forests, and slightly reduced the chance of crown burn in younger aged, mixed species forest.

    The impact of thinning varied with forest type, the age of the forest and fire conditions.

    --

    Across most forest types and ages, thinning had little impact on forest fire severity, although it did worsen severity in mixed species forest aged 70 years plus and did reduce it in mixed species forest aged 20-40 years. Overall, the evidence indicates thinning forests does not reduce fire risk.

    Chris Taylor et al. Does forest thinning reduce fire severity in Australian eucalypt forests?, Conservation Letters (2020). DOI: 10.1111/conl.12766

    https://phys.org/news/2020-10-thinning-forests-defence.html?utm_sou...

  • Dr. Krishna Kumari Challa

    Signals from distant stars connect optical atomic clocks across Earth for the first time

    Using radio telescopes observing distant stars, scientists have connected optical atomic clocks on different continents.

     Marco Pizzocaro et al, Intercontinental comparison of optical atomic clocks through very long baseline interferometry, Nature Physics (2020). DOI: 10.1038/s41567-020-01038-6

    In this new research, highly-energetic extragalactic radio sources replace satellites as the source of reference signals. The group of Sekido Mamoru at NICT designed two special radio telescopes, one deployed in Japan and the other in Italy, to realize the connection using the technique of Very Long Baseline Interferometry (VLBI). These telescopes are capable of observations over a large bandwidth, while antenna dishes of just 2.4 meter diameter keep them transportable.

    https://phys.org/news/2020-10-distant-stars-optical-atomic-clocks.h...

  • Dr. Krishna Kumari Challa

    Stomach Acid & Heartburn Drugs Linked with COVID-19 Outcomes


    While sick with COVID-19, President Trump is taking an antacid. Doctors have been exploring whether these medicines can treat SARS-CoV-2 infections, and the results are mixed.

    The uncertainty of the COVID-19 pandemic has made our stomachs churn, and now, evidence suggests that intense heartburn may be linked with worse symptoms of the disease. Some drugs that neutralize stomach acid, such as famotidine, which President Donald Trump is taking, are associated with reduced severity, but others, such as Prilosec, correlate with higher infection rates and risk of death, at least in patients hospitalized with SARS-CoV-2 infections.

    https://www.the-scientist.com/news-opinion/stomach-acid-heartburn-d...


  • Dr. Krishna Kumari Challa

    Millimetre-precision drug delivery to the brain

    Researchers  have developed a method for concentrating and releasing drugs in the brain with pinpoint accuracy. This could make it possible in the future to deliver psychiatric and cancer drugs and other medications only to those regions of the brain where this is medically desirable.

    In order to prevent a drug from acting on the entire brain and body, the new method involves special drug carriers that wrap the drugs in spherical lipid vesicles attached to gas-​containing ultrasound-​sensitive microbubbles. These are injected into the bloodstream, which transports them to the brain. Next, the scientists use focused ultrasound waves in a two-​stage process. Focused ultrasound is already employed in oncology to destroy cancer tissue at precisely defined points in the body. In the new invention, however, the scientists work with much lower energy levels, which do not damage the tissue.

    Ozdas MS, Shah AS, Johnson PM, Patel N, Marks M, Yasar TB, Stalder U, Bigler L, von der Behrens W, Sirsi SR, Yanik MF: Non-​invasive molecularly-​specific millimeterresolution manipulation of brain circuits by ultrasound-​mediated aggregation and uncaging of drug carriers. Nature Communications, 1 October 2020, doi: 10.1038/s41467-​020-18059-7

    https://ethz.ch/en/news-and-events/eth-news/news/2020/10/millimetre...

    https://researchnews.cc/news/2923/Millimetre-precision-drug-deliver...

  • Dr. Krishna Kumari Challa

    This ‘squidbot’ jets around and takes pics of coral and fish

  • Dr. Krishna Kumari Challa

    More Humans Are Growing an Extra Artery in Our Arms, Showing We're Still Evolving

    Researchers have noticed an artery that temporarily runs down the centre of our forearms while we're still in the womb isn't vanishing as often as it used to.

    That means there are more adults than ever running around with what amounts to be an extra channel of vascular tissue flowing under their wrist.

    Since the 18th century, anatomists have been studying the prevalence of this artery in adults and our study shows it's clearly increasing.

    The prevalence was around 10 percent in people born in the mid-1880s compared to 30 percent in those born in the late 20th century, so that's a significant increase in a fairly short period of time, when it comes to evolution.

    Recently increased prevalence of the human median artery of the forearm: A microevolutionary change
    The median artery has been considered as an embryonic structure, which normally regresses around the 8th week of gestation. However, various prevalences have been reported in adults since the 18th century. Furthermore, in a study by Henneberg and George (1995; Am J Phys Anthropol 96, 329–334), has suggested that increasing prevalence of the median artery during the 20th century was a ‘possible secular trend’. The present study, conducted nearly a quarter of a century later, is a continuation of that study. A total of 26 median arteries were found in 78 upper limbs obtained from Australians aged 51 to 101 years, who died in the period 2015–2016, a prevalence rate of 33.3%. Analysis of the literature showed that the presence of the median artery has been significantly increasing (p = .001) over time, from approximately 10% in people born in the mid‐1880s to approximately 30% by the end of the 20th century. The significance of the prevalence increased to a p value
  • Dr. Krishna Kumari Challa

    A bird is male on one side and female on the other

    Male rose-breasted grosbeaks have some red-pink feathers while females’ are yellow and brown

    A rose-breasted grosbeak has a pink breast spot and a pink “wing pit” and black feathers on its right wing — tell tale shades of males. But on its left side, the songbird displays yellow and brown plumage, hues typical of females.

    Gynandromorphs are found in many species of birds, insects and crustaceans such as crabs and lobsters. This bird is likely the result of an unusual event when two sperm fertilize an egg that has two nuclei instead of one. The egg can then develop male sex chromosomes on one side and female sex chromosomes on the other, ultimately leading to a bird with a testis and other male characteristics on one half of its body and an ovary and other female qualities on the other half.

    Unlike hermaphrodites, which also have genitals of both sexes, gynandromorphs are completely male on one side of the body and female on the other.

    We don’t yet know if these birds behave more like males or females, or if they can reproduce

    R.J. Agate et alNeural, not gonadal, origin of brain sex differences in a gynandrom...Proceedings of the National Academy of Sciences. Vol. 100, April 15, 2003, p. 4873. doi: 10.1073/pnas.0636925100.

    RESEARCHERS AT POWDERMILL NATURE RESERVE OBSERVE RARE GYNANDROMORPH BIRD CONTAINING BOTH MALE AND FEMALE CHARACTERISTICS - Carnegie Museum of Natural History
  • Dr. Krishna Kumari Challa

    Some Fish Can Regenerate Their Eyes. Know what? Mammals Have Those Genes Too to do that.

    But, they are switched off! Scientists want to switch them on again.

    Damage to the retina is the leading cause of blindness in humans, affecting millions of people around the world. Unfortunately, the retina is one of the few tissues we humans can't grow back. Unlike us, other animals such as zebrafish are able to regenerate this tissue that's so crucial to our power of sight. We share 70% of our genes with these tiny little zebrafish, and scientists have just discovered some of the shared genes include the ones that grant zebrafish the ability to grow back their retinas.

    The genes activated were involved in containing the injury, calling in immune cells to clean up damaged tissue and fight off potential invaders.

    But then, a network that suppresses these genes kicked in only in their mouse subjects, keeping them from transforming into cells that produce other kinds of retinal cells. Researchers suspect that the loss of this ability may be linked to a trade-off between regenerating central nervous system cells and parasite resistance. Glia help restrict the spread of infections, and if they're turned into neuron-producing cells, they can't do this.

    The researchers also noticed that after a retinal injury glial cells in all three species stopped making nuclear factor I (NFI), a protein that stops the cell from accessing bits of DNA, essentially turning genes off.

    But in mice, this molecule started appearing again fairly soon. So, the team stopped Müller glia cells producing NFI and the cells started making retinal neurons in adult mice after injury.

    This is a highly complicated system with many independent mechanisms involved that need to be further explored. But understanding these pathways may one day allow scientists to help us better repair damaged sight.

    Gene regulatory networks controlling vertebrate retinal regeneration

  • Dr. Krishna Kumari Challa

    Study reveals that methods to infer the connectivity of neural circuits are affected by systematic errors

    Researchers  have recently carried out a study investigating the effectiveness of existing methods for algorithmically estimating the wiring of neural networks. Their findings suggest that even the most sophisticated among these methods are biased and tend to infer connections between neurons that are not actually connected, but rather highly correlated.

    Because it is difficult to directly measure the wiring diagrams of neural circuits, there has long been an interest in estimating them algorithmically from multicell activity recordings. But this study shows even sophisticated methods, applied to unlimited data from every cell in the circuit, are biased toward inferring connections between unconnected but highly correlated neurons. This failure to 'explain why' connections occurs when there is a mismatch between the true network dynamics and the model used for inference, which is inevitable when modeling the real world.

    Abhranil Das et al. Systematic errors in connectivity inferred from activity in strongly recurrent networks, Nature Neuroscience (2020). DOI: 10.1038/s41593-020-0699-2

    https://medicalxpress.com/news/2020-10-reveals-methods-infer-neural...

  • Dr. Krishna Kumari Challa

    'Universal law of touch' will enable new advances in virtual reality

    Seismic waves, commonly associated with earthquakes, have been used by scientists to develop a universal scaling law for the sense of touch.

    Rayleigh waves are created by impact between objects and are commonly thought to travel only along surfaces. The team discovered that, when it comes to touch, the waves also travel through layers of skin and bone and are picked up by the body's touch receptor cells.

    Using mathematical modelling of these touch receptors the researchers showed how the receptors were located at depths that allowed them to respond to Rayleigh waves. The interaction of these receptors with the Rayleigh waves will vary across species, but the ratio of receptor depth vs wavelength remains the same, enabling the universal law to be defined.

    The team also found that the interaction of the waves and receptors remained even when the stiffness of the outermost layer of skin changed. The ability of the receptors to respond to Rayleigh waves remained unchanged despite the many variations in this outer layer caused by, age, gender, profession, or even hydration.

    For most mammals, touch is the first sense to develop. They must feel vibrations on the surface of their skin to enable them to respond to various stimuli in their environment, a process called vibrotaction. But how do mammals perceive these vibrations? Through mathematical modeling of the skin and touch receptors, researchers showed that vibrotaction is dominated by “surface” Rayleigh waves traveling cooperatively through all layers of the skin and bone. Applying their model to experimental data, they identified a universal scaling law for the depth of touch receptors across multiple species, indicating an evolutionarily conserved constant in the sensation of vibrations.

     J.W. Andrews el al., "A universal scaling law of mammalian touch," Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.abb6912

    https://phys.org/news/2020-10-universal-law-enable-advances-virtual...

  • Dr. Krishna Kumari Challa

    **Do cloth masks work? Only if you machine wash them after every single use

    A new publication from researchers  advises daily washing of cloth masks to reduce the likelihood of contamination and transmission of viruses like SARS-CoV-2. Cloth masks must be washed daily at high temperatures to be protective against infection, a new analysis shows. It was found that if cloth masks were washed in the hospital laundry, they were as effective as a surgical mask.

    It is important to note that given the study was conducted over five years ago, the researchers did not test for SARS-CoV-2—instead, they included common respiratory pathogens such as influenza, rhinoviruses and seasonal coronaviruses in their analysis. It is based on self-reported washing data and was conducted by health workers in high risk wards in a healthcare setting.

    "While someone from the general public wearing a cloth mask is unlikely to come into contact with the same amount of pathogens as healthcare worker in a high risk ward, we would still recommended daily washing of cloth masks in the community. COVID-19 is a highly infectious virus, and there is still a lot that we don't know about it, and so it's important that we take every precaution we can to protect against it and ensure masks are effective.

    According to the analysis, handwashing the masks did not provide adequate protection. Healthcare workers who self-washed their masks by hand had double the risk of infection compared to those who used the hospital laundry

    The WHO recommends machine washing masks with hot water at 60 degrees Celsius and laundry detergent, and the results of our analysis support this recommendation.

    Washing machines often have a default temperature of 40 degree or 60 degrees, so do check the setting. At these very hot temperatures, handwashing is not possible. The clear message from this research is that cloth masks do work—but once a cloth mask has been worn, it needs to be washed properly each time before being worn again, otherwise it stops being effective.

    There is much research on the design, fabric and construction of masks, but washing is also key for protection.

    Chandini Raina MacIntyre et al. Contamination and washing of cloth masks and risk of infection among hospital health workers in Vietnam: a post hoc analysis of a randomized controlled trial, BMJ Open (2020). DOI: 10.1136/bmjopen-2020-042045

    https://medicalxpress.com/news/2020-10-masks-machine.html?utm_sourc...

  • Dr. Krishna Kumari Challa

    Bacteria-fighting cells in the airways boost infection risk from viruses

    Having more bacteria-fighting immune cells in the nose and throat may explain why some people are more likely to be infected by respiratory viruses.

    researchers found that volunteers who succumbed to infection from respiratory syncytial virus (RSV) had more specialized white blood cells called neutrophils in their airways before exposure to the virus, compared to those who staved off infection. According to the researchers, this type of neutrophil-driven inflammation in the nose and throat—typically associated with fighting off bacterial infections—may compromise our ability to fight off invading viruses and make us more susceptible to viral infections. The findings could help researchers to understand why people respond differently to the same viral threat, predict who is more at risk of infection, and even lead to preventative treatments to protect against RSV and potentially other respiratory viruses, including influenza and coronaviruses. when they analyzed samples from participants' airways taken before they were exposed to the virus, the team found evidence of neutrophil activation in the nasal mucosa—the cells lining the inside of the nose—in those who became infected with the virus. These immune cells are known to release proteins which help create an antibacterial environment in response to a threat. But the researchers believe this antibacterial immune response may come at a cost, making a host more susceptible to viruses by effectively switching off the early warning system, letting them slip through the net to cause infection.

     Neutrophilic inflammation in the respiratory mucosa predisposes to RSV infection. Sciencescience.sciencemag.org/cgi/doi … 1126/science.aba9301

    https://medicalxpress.com/news/2020-10-bacteria-fighting-cells-airw...

  • Dr. Krishna Kumari Challa

    4-D nanoparticles open new perspectives in safer treatment of tumor...

    In the context of nanomedicine, nanoparticles are effective because they can be endowed with multiple functions and are able to hit their target without the need for extremely high doses, which are associated with dangerous side effects. However, they tend to remain in the body for an indefinite time, with important risks to the health of patients. Ideally, nanomedicines should behave like a 4-D material, developing nanoparticles for diagnosis (for example by magnetic resonance imaging or CT scan) and cancer therapy that have as their main requirement the ability to biodegrade, not to accumulate in the body, limiting it in this way the side effects.

    inorganic nanoparticles based on an alloy of gold and iron, two biocompatible elements, which are therefore particularly suitable for applications in the biomedical field, are able to biodegrade spontaneously in living organisms.

     how the possibility of capturing these "4-D nano-comets" is fundamental in the field of nanomedicine, and especially for the diagnosis and treatment of cancer, showing that metastable gold-iron-based nanoalloys could be ideal candidates for the purpose.

    The research, which started with a theoretical-computational investigation, has shown how the atoms of gold and iron, two biocompatible elements that are particularly suitable for applications in the biomedical field, must be arranged inside the nanoparticles so that the latter biodegrade spontaneously in living organisms. The key to the whole study was to find a way to "force" iron and gold to coexist in proportions that are not practicable in nature. For this purpose, laser synthesis techniques in liquid were used to produce bi-metallic Au-Fe nanoparticles capable of biodegradation. These metastable nanoparticles have also been tested in vivo, where they have been shown to leave the organism after a not excessively long period, as opposed to other nanoparticles based only on gold or only on iron oxide, which instead tend to persist for much longer times.

    Having a 4-D nanomaterial exploitable as a multimodal imaging agent is particularly important at a clinical level because it allows reducing both the dose administered to the patient and the waiting time before the imaging itself, which are crucial in the treatment of tumors. The next step will be the investigation of the theranostic (i.e., diagnostic and therapeutic) potential of these 4-D nanomedicines.

    Veronica Torresan et al. 4D Multimodal Nanomedicines Made of Nonequilibrium Au–Fe Alloy Nanoparticles, ACS Nano (2020). DOI: 10.1021/acsnano.0c03614

    https://sciencex.com/news/2020-10-d-nanoparticles-perspectives-safe...

  • Dr. Krishna Kumari Challa

    Finding the Best Hot Pepper Cures Using SCIENCE

  • Dr. Krishna Kumari Challa

    How SARS-CoV-2 disables the human cellular alarm system

    https://phys.org/news/2020-10-sars-cov-disables-human-cellular-alar...

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    How gut bacteria manipulates your immune system – by mimicking it

    Scientists are discovering how microbes ‘speak’ with the body

    https://massivesci.com/articles/gut-bacteria-immune-system-protein-...

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    What do we really know about the safety of probiotics?

    Messing with our gut microbiome could hurt us

    https://massivesci.com/articles/probiotics-microbiome-supplements/

    --

    Initiative pushes to make journal abstracts free to read in one place

    Publishers agree to make journal summaries open and searchable in single repository.
    In a bid to boost the reach and reuse of scientific results, a group of scholarly publishers has pledged to make abstracts of research papers free to read in a cross-disciplinary repository.
    https://www.nature.com/articles/d41586-020-02851-y?utm_source=Natur...
  • Dr. Krishna Kumari Challa

    Cheese Preservative Slows Oral Cancer Spread in Mice: Study

    The results add to mounting evidence of microbes’ roles in tumor growth and point to the possibility of impeding malignancies by inhibiting bacteria.

    https://www.the-scientist.com/news-opinion/cheese-preservative-slow...

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    How media algorithms try to manipulate your decisions and how to overcome them

    https://theconversation.com/do-social-media-algorithms-erode-our-ab...

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    Astronomers Are Using Black Hole Echoes to Help Map The Universe

    https://www.sciencealert.com/echoes-from-black-holes-could-be-the-n...

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    Chemists create new crystal form of insecticide, boosting its ability to fight mosquitoes and malaria

    https://phys.org/news/2020-10-chemists-crystal-insecticide-boosting...

  • Dr. Krishna Kumari Challa

     Fertiliser use is fuelling climate-warming nitrous oxide emissions: study

    https://www.reuters.com/article/us-climate-change-no2-idUSKBN26S35W

    --

    Life in the Clouds

    High above our heads, even beyond 120,000 feet up, scientists have found tiny organisms called microbes. These high-flyers were swept up from the ground by winds and storms, or spewed out through volcanic processes. While most of these high-altitude microbes are dead, some are still alive, or have produced material called spores that could activate in the future. David J. Smith, an astrobiologist at NASA’s Ames Research Center, uses airplanes to collect these microbes, analyze them in the laboratory, and expose them to even higher altitudes with balloon experiments to see how they will respond. If microbes can inhabit our clouds, what about other planets? While more research is needed, Smith and others are fascinated by the possibility that airborne microbes could also be found elsewhere in the solar system, and beyond.

  • Dr. Krishna Kumari Challa

    Scientists May Be Able to Treat Tinnitus With Electronic Music And Tongue Buzzing

    People who experience tinnitus (the perception of noise or ringing in the ears) might finally have some hope for alleviating their symptoms, after an experimental device that stimulates the tongue was found to ease the condition in a sample of 273 volunteers with a chronic case of it.The tongue buzzing is combined with a carefully prepared audio stream fed through headphones, sounding a little like ambient electronic music. The combined treatment caused an improvement in symptoms for 86 percent of the participants, with an average drop of around 14 points on a tinnitus severity ranking scored from 1 to 100. Even better, the improvements lasted for up to a year for many of the individuals involved. These are promising signs for the 10-15 percent of people worldwide who live with the phantom sounds and ringing ears caused by tinnitus.

     device – called the Lenire – aims to heighten the sensitivity of the brain, effectively crowding out the overactive parts of the brain that would otherwise cause tinnitus symptoms.

    https://stm.sciencemag.org/content/12/564/eabb2830

    https://www.sciencealert.com/audible-tones-and-tongue-buzzing-could...

  • Dr. Krishna Kumari Challa

    New virtual reality software allows scientists to 'walk' inside cells

    Virtual reality software which allows researchers to 'walk' inside and analyse individual cells could be used to understand fundamental problems in biology and develop new treatments for disease. The software, called vLUME, was created by scientists. It allows super-resolution microscopy data to be visualised and analysed in virtual reality, and can be used to study everything from individual proteins to entire cells.

    Super-resolution microscopy, which was awarded the Nobel Prize for Chemistry in 2014, makes it possible to obtain images at the nanoscale by using clever tricks of physics to get around the limits imposed by light diffraction. This has allowed researchers to observe molecular processes as they happen. However, a problem has been the lack of ways to visualise and analyse this data in three dimensions.

    vLUME is revolutionary imaging software that brings humans into the nanoscale. It allows scientists to visualise, question and interact with 3-D biological data, in real time all within a virtual reality environment, to find answers to biological questions faster. It's a new tool for new discoveries. Viewing data in this way can stimulate new initiatives and ideas.

    vLUME: 3D virtual reality for single-molecule localization microscopy, Nature Methods (2020). DOI: 10.1038/s41592-020-0962-1

    https://techxplore.com/news/2020-10-virtual-reality-software-scient...

  • Dr. Krishna Kumari Challa

    Experimental COVID-19 treatment given to Trump found to relieve symptoms in macaques and hamsters

    A team of researchers with Regeneron Pharmaceuticals, Inc., working with the Texas Biomedical Research Institute, has found that the antibody cocktail given to President Trump was effective in reducing COVID-19 symptoms in rhesus macaques and golden hamsters. 

    The US president had received an experimental antibody cocktail along with doses of vitamin D, zinc and a heartburn medicine. The experimental antibody cocktail he was given was provided courtesy of Regeneron Pharmaceuticals, Inc., a company that has been conducting research into the use of such antibody cocktails as therapies for a host of viral infections, including COVID-19. In this new effort, the researchers tested the antibody cocktail with rhesus macaques and golden hamsters.

    In the first part of the study, the researchers administered the cocktail (which they call REGN-COV2) to healthy rhesus macaques. Prior research had shown that they can infected by the SARS-CoV-2 virus, but typically exhibit only mild symptoms. Three days after receiving the cocktail, the monkeys were injected with the SARS-CoV-2 virus and then monitored to see if the treatment had any impact. They found that monkeys who had received the treatment prior to infection exhibited far fewer symptoms than a control group and had a much lower viral load.

    The researchers also injected some of the monkeys with the cocktail after they were infected and found that doing so also reduced symptoms and resulted in faster viral clearance. The researchers next repeated the same experiments with golden hamsters. They, too, have been found to be susceptible to COVID-19, but have much more severe symptoms, including major weight loss. They found that giving it to them two days before they were infected with the SARS-CoV-2 virus resulted in greatly reduced symptoms and they did not suffer weight loss. And giving it to the hamsters after an infection had set in also resulted in reduced symptoms and faster viral clearance.

    The researchers suggest that REGN-COV2 may offer therapeutic benefits both as a treatment and as a preventative measure for COVID-19.

    Alina Baum et al. REGN-COV2 antibodies prevent and treat SARS-CoV-2 infection in rhesus macaques and hamsters, Science (2020). DOI: 10.1126/science.abe2402

    https://medicalxpress.com/news/2020-10-experimental-covid-treatment...

  • Dr. Krishna Kumari Challa

    Dueling proteins give shape to plants

    In an elegant choreography, plants take cues from their environment and channel them into flowers, roots, or branches.

    Researchers have been studying two key groups of proteins that influence plant form and timing of developmental transitions. Terminal Flower 1 (TLF1) proteins promote branch formation. When it is repressed, flowers grow. Flowering Locus T (FT) proteins, on the other hand, promote flowering in response to seasonal cues like day length. Strangely enough, the two proteins are almost identical.

    These two elements have significance galore. Besides flowering, they're involved in tuberization in potatoes, bulb formation in onions, tendril formation in grapes, growth cessation in trees, lots of things.

    Manipulating these genes, some have argued, could lead to the next "green revolution" as one could theoretically "trick" a plant that normally only flowers in the long days of summer to flower quickly, and thus produce fruit or seed, in the short days of winter with a deft genetic edit of TFL1. Or, in an area with a longer growing season, a clever manipulation of growth architecture via FT could encourage increased branching and then a later, and more abundant, flowering and fruit development on the many branches.

    Nature Communications (2020). DOI: 10.1038/s41467-020-18782

    --

    Plants have already been bred to have reduced TFL1 activity. Tomato gardeners may know these as determinant plants, which set all their flowers at the same time, as opposed to the indeterminant variety, which continue to branch, flower, and fruit over a period of months. Determinant plants make commercial agriculture more efficient, as fruits can be harvested in one go as opposed to repeated passes.

    https://phys.org/news/2020-10-dueling-proteins.html?utm_source=nwle...

  • Dr. Krishna Kumari Challa

    Scientists engineer bacteria-killing molecules from wasp venom

    A team led by scientists  has engineered powerful new antimicrobial molecules from toxic proteins found in wasp venom. The team hopes to develop the molecules into new bacteria-killing drugs, an important advancement considering increasing numbers of antibiotic-resistant bacteria which can cause illness such as sepsis and tuberculosis.

    The  researchers altered a highly toxic small protein from a common Asian wasp species, Vespula lewisii, the Korean yellow-jacket wasp. The alterations enhanced the molecule's ability to kill bacterial cells while greatly reducing its ability to harm human cells. In animal models, the scientists showed that this family of new antimicrobial molecules made with these alterations could protect mice from otherwise lethal bacterial infections.

     Osmar N. Silva el al., "Repurposing a peptide toxin from wasp venom into antiinfectives with dual antimicrobial and immunomodulatory properties," PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.2012379117

    https://phys.org/news/2020-10-scientists-bacteria-killing-molecules...

  • Dr. Krishna Kumari Challa

    Carnivores living near people feast on human food, threatening ecosystems

    Ecologists  have found that carnivores living near people can get more than half of their diets from human food sources, a major lifestyle disruption that could put North America's carnivore-dominated ecosystems at risk. The researchers studied the diets of seven predator species across the Great Lakes region of the U.S. They gathered bone and fur samples for chemical analysis from areas as remote as national parks to major metropolitan regions like Albany, New York. They found that the closer carnivores lived to cities and farms, the more human food they ate.

     Philip J. Manlick el al., "Human disturbance increases trophic niche overlap in terrestrial carnivore communities," PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.2012774117

    https://phys.org/news/2020-10-carnivores-people-feast-human-food.ht...

  • Dr. Krishna Kumari Challa

    **Oral cancer pain predicts likelihood of cancer spreading

     Oral cancer is more likely to spread in patients experiencing high levels of pain, according to a team of researchers at New York University College of Dentistry that found genetic and cellular clues as to why metastatic oral cancers are so painful.

    The findings—which appear in Scientific Reports, a journal published by Nature—may ultimately be used to alleviate oral cancer pain and refine surgical decision making when treating oral cancer.

    Oral cancer can cause severe pain during everyday activities, including talking and eating. Previous research by Brian L. Schmidt, DDS, MD, PhD, director of the NYU Oral Cancer Center and one of the study’s authors, suggests that patients with metastatic oral cancer—cancer that spreads beyond the mouth—experience more pain than those whose cancer has not spread. The new study helps researchers understand why.

    https://researchnews.cc/news/3000/Oral-cancer-pain-predicts-likelih...

  • Dr. Krishna Kumari Challa

    New Type of Immunotherapy Helps Mice with Hard-to-Treat Breast Cancer Survive Longer

  • Dr. Krishna Kumari Challa

    Where You Sit in a Room Can Influence Your Risk of Catching COVID-19

    https://www.sciencealert.com/where-you-sit-in-a-classroom-might-inf...

    --

    ** 

    Non-Concussive Head Hits Influence the Brain’s Microstructure

    Comparing the brain scans of high-impact rugby players with those of athletes in noncontact sports, such as rowing and swimming, revealed tiny, yet significant, differences in the brain’s white matter.

    https://www.the-scientist.com/the-literature/non-concussive-head-hi...

  • Dr. Krishna Kumari Challa

    Binge drinking may cause Alzheimer's disease—and it might strike younger and in a severe form

    Binge drinking may be linked to both the onset and severity of Alzheimer's disease, but scientists have only now embarked on a path to decipher each molecular step involved in how excessive alcohol consumption leads to the most common form of dementia.

    Excessive alcohol consumption is toxic to the brain. Binge drinking likely plays an insidious role in the alteration of a normal brain protein  into a biological rogue that is highly prevalent in Alzheimer's disease. The protein is identified by a simplistic monosyllabic name—tau.

    In its normal conformation, tau is found in neurons modulating the stability of axonal microtubules. But in its abnormal conformation, tau has long been considered one of the leading hallmarks of Alzheimer's, and makes up the tangles in the notorious "plaques and tangles" pathology. The plaques are deposits of the protein beta amyloid. 

     The main aim of this study is how tau transforms from a normal protein into a neuron-annihilating cause of Alzheimer's under the influence of excessive alcohol. 

    The scientists are delving into how tau can become phosphorylated, which means its structural conformation changes and its role in the brain becomes chemically altered under the influence of binge drinking. Studies have shown that frequent and heavy alcohol drinking is linked to earlier onset and increased severity of Alzheimer's disease.

    It has been reported that alcohol consumption correlates with Alzheimer's-like cortical atrophy in individuals at high risk of developing the disease as well as younger age of onset.

    In addition, chronic alcohol exposure caused neural tau phosphorylation in the hippocampus and memory-impairment in Alzheimer's-predisposed mice.

    Archna Sharma et al. Potential Role of Extracellular CIRP in Alcohol-Induced Alzheimer's Disease, Molecular Neurobiology (2020). DOI: 10.1007/s12035-020-02075-1

    https://medicalxpress.com/news/2020-10-binge-alzheimer-diseaseand-y...

  • Dr. Krishna Kumari Challa

    Covid-19 reinfection casts doubt on virus immunity: study

    COVID-19 patients may experience more severe symptoms the second time they are infected, according to research released this week confirming it is possible to catch the potentially deadly disease more than once.

    The study charts the first confirmed case of COVID-19 reinfection in the United States. 

    The patient, a 25-year-old man, was infected with two distinct variants of SARS-CoV-2, the virus that causes COVID-19, within a 48-day time frame.

    The second infection was more severe than the first, resulting in the patient being hospitalised with oxygen support.

    The study also reminded us the four other cases of reinfection confirmed globally, with one patient each in Belgium, the Netherlands, Hong Kong and Ecuador. Experts say the prospect of reinfection could have a profound impact on how the world battles through the pandemic. In particular, it could influence the hunt for a vaccine.

    Vaccines work by triggering the body's natural immune response to a certain pathogen, arming it with antibodies it to fight off future waves of infection.

    But it is not at all clear how long COVID-19 antibodies last.

    For some diseases, such as measles, infection confers lifelong immunity. For other pathogens, immunity may be fleeting at best.

    The authors said the US patient could have been exposed to a very high dose of the virus the second time around, triggering a more acute reaction.

    Alternatively, it may have been a more virulent strain of the virus.

    Another hypothesis is a mechanism known as antibody dependent enhancement—that is, when antibodies actually make subsequent infections worse, such as with dengue fever.

    The researchers pointed out that reinfection of any kind remains rare, with only a handful of confirmed cases out of tens of millions of COVID-19 infections globally.

    However, since many cases are asymptomatic and therefore unlikely to have tested positive initially, it may be impossible to know if a given COVID-19 case is the first or second infection.

    https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30764-7/fulltext

    https://medicalxpress.com/news/2020-10-covid-reinfection-virus-immu...

  • Dr. Krishna Kumari Challa

    Damaged muscles don't just die, they regenerate themselves

    Researchers have found that components leaking from broken muscle fibers activate "satellite" muscle stem cells. While attempting to identify the proteins that activate satellite cells, they found that metabolic enzymes, such as GAPDH, rapidly activated dormant satellite cells and accelerated muscle injury regeneration. This is a highly rational and efficient regeneration mechanism in which the damaged muscle itself activates the satellite cells that begin the regeneration process.

    Skeletal muscle is made up of bundles of contracting muscle fibers and each muscle fiber is surrounded by satellite cells—muscle stem cells that can produce new muscle fibers. Thanks to the work of these satellite cells, muscle fibers can be regenerated even after being bruised or torn during intense exercise. Satellite cells also play essential roles in muscle growth during developmental stages and muscle hypertrophy during strength training. However, in refractory muscle diseases like muscular dystrophy and age-related muscular fragility (sarcopenia), the number and function of satellite cells decreases. It is therefore important to understand the regulatory mechanism of satellite cells in muscle regeneration therapy.

    In mature skeletal muscle, satellite cells are usually present in a dormant state. Upon stimulation after muscle injury, satellite cells are rapidly activated and proliferate repeatedly. During the subsequent myogenesis, they differentiate and regenerate muscle fibers by fusing with existing muscle fibers or with together. Of these three steps (satellite cell activation, proliferation, and muscle differentiation), little is known about how the first step, activation, is induced.

    Since satellite cells are activated when muscle fibers are damaged, researchers hypothesized that muscle damage itself could trigger activation

    Yoshifumi Tsuchiya et al, Damaged Myofiber-Derived Metabolic Enzymes Act as Activators of Muscle Satellite Cells, Stem Cell Reports (2020). DOI: 10.1016/j.stemcr.2020.08.002

    Skeletal muscles and satellite cells: How exercise leads to longer ...
    https://medicalxpress.com/news/2020-10-muscles-dont-die-regenerate....
  • Dr. Krishna Kumari Challa

    Skeletal muscle development and regeneration mechanisms vary by gender

    Researchers at Kumamoto University, Japan, have generated mice lacking the estrogen receptor beta (ERβ) gene, both fiber-specific and muscle stem cell-specific, which resulted in abnormalities in the growth and regeneration of skeletal muscle in female mice. This was not observed in male mice that lacked the ERβ gene, suggesting that estrogen and its downstream signals may be a female-specific mechanism for muscle growth and regeneration.

    In humans, skeletal muscle mass generally peaks in the 20s with a gradual decline beginning in the 30s, but it is possible to maintain muscle mass through strength training and a healthy lifestyle. Skeletal muscle can be damaged through excessive exercise or bruising, but it has the ability to regenerate. The muscle stem cells that surround muscle fibers are essential for this regeneration; they also play a part in increasing muscle size (hypertrophy). Muscle stem cell dysfunction is thought to be associated with various muscle weakness, such as age-related sarcopenia and muscular dystrophy. Although basic research on skeletal muscle has progressed rapidly in recent years, most studies were conducted on male animals and gender differences were given much consideration.

    Estrogen is a female hormone that maintains the homeostasis of various tissues and organs. A decrease in estrogen levels due to amenorrhea, menopause, or other factors can lead to a disturbance in biological homeostasis. When estrogen binds to estrogen receptors (ERs) in cells, it is transferred into the nucleus and binds to genomic DNA to induce the expression of specific genes as transcription factors. There are two types of ERs, ERα and ERβ. While both ERα and ERβ have high binding capacity to estrogen, their tissue distribution is different, they do not have a common DNA-binding domain, and they may act as antagonists to each other, suggesting that they have different roles. Furthermore, estrogen's effects on cells can be both ER-mediated and non-ER-mediated.

    An epidemiological study of pre- and postmenopausal women in their 50s indicated an association between decreased blood estrogen levels and muscle weakness. A research group at Kumamoto University previously showed that estrogen is important for skeletal muscle development and regeneration using an ovariectomized estrogen deficiency mouse model. They also examined the effectiveness of nutritional interventions in estrogen-deficient conditions. However, whether estrogen acts directly on the ER of muscle fibers and muscle stem cells to regulate skeletal muscle growth and regeneration, or whether it acts indirectly through other tissues and organs was unclear. In this study, the researchers generated mice with either myofiber-specific or muscle stem cell-specific ERβ gene deletion and analyzed the function of ERβ in skeletal muscle.

    Daiki Seko et al, Estrogen Receptor β Controls Muscle Growth and Regeneration in Young Female Mice, Stem Cell Reports (2020). DOI: 10.1016/j.stemcr.2020.07.017

    https://medicalxpress.com/news/2020-10-skeletal-muscle-regeneration...

  • Dr. Krishna Kumari Challa

    Physicists successfully carry out controlled transport of stored light

    A team of physicists has successfully transported light stored in a quantum memory over a distance of 1.2 millimeters. They have demonstrated that the controlled transport process and its dynamics has only little impact on the properties of the stored light. The researchers used ultra-cold rubidium-87 atoms as a storage medium for the light as to achieve a high level of storage efficiency and a long lifetime.

    They stored the light by putting it in a 'suitcase' so to speak, only that in their case the suitcase was made of a cloud of cold atoms. They then moved this suitcase over a short distance and then took the light out again. This is very interesting not only for physics in general, but also for quantum communication, because light is not very easy to 'capture', and if you want to transport it elsewhere in a controlled manner, it usually ends up being lost.

    --

    The controlled manipulation and storage of quantum information as well as the ability to retrieve it are essential prerequisites for achieving advances in quantum communication and for performing corresponding computer operations in the quantum world. Optical quantum memories, which allow for the storage and on-demand retrieval of quantum information carried by light, are essential for scalable quantum communication networks. For instance, they can represent important building blocks of quantum repeaters or tools in linear quantum computing. In recent years, ensembles of atoms have proven to be media well suited for storing and retrieving optical quantum information. Using a technique known as electromagnetically induced transparency (EIT), incident light pulses can be trapped and coherently mapped to create a collective excitation of the storage atoms. Since the process is largely reversible, the light can then be retrieved again with high efficiency.

    Wei Li et al, Controlled Transport of Stored Light, Physical Review Letters (2020). DOI: 10.1103/PhysRevLett.125.150501

    https://phys.org/news/2020-10-physicists-successfully.html?utm_sour...

  • Dr. Krishna Kumari Challa

    How to see what's on the other side of a wormhole without actually traveling through it

    Wormholes are incredibly fascinating objects, but also completely hypothetical. We simply don't know if they can truly exist in our universe. But new theoretical insights are showing how we may be able to detect a wormhole—from a spray of high-energy particles emitted at the moment of its formation.

    The problem with wormholes - Ask a Spaceman!

    O. B. Zaslavskii, New scenario of high-energy particle collisions near wormholes. arXiv:2009.11894 [gr-qc]. arxiv.org/abs/2009.11894

    https://phys.org/news/2020-10-side-wormhole.html?utm_source=nwlette...

     it might be possible to find wormholes, and a new paper appearing on the preprint journal arXiv outlines one possible technique.

    Here's how it works. Let's say a particle falls into a newly forming wormhole. It can, if it has high enough energy, spontaneously decay into two new particles. One of these particles can escape through the wormhole, while the other can get reflected back through the opening, due to the strange physics operating inside these tunnels.

    Then, a new particle enters the wormhole and collides with the reflected particle. The author of the paper found that this collision can reach arbitrarily high energies. This means that what we see on our end of the wormhole could be a shower of high-energy radiation—an unmistakable burst of energy.

    Now that we know these kinds of particle showers are possible from opening wormholes, we can look around the universe to see if anything fits the bill… and if we can travel to them.

  • Dr. Krishna Kumari Challa

    Earphone tracks facial expressions, even with a face mask

    C-Face: Continuously Reconstructing Facial Expressions by Deep Learning Contours ,UIST 20, SciFi Lab

  • Dr. Krishna Kumari Challa

    Multivitamins Don't Necessarily Make You Healthier. Here's Why

    Do multivitamins make you healthier?

    Some peopel take multivitamins daily on the idea that they help improve overall health and potentially lower disease. Is their any science behind the health benefits of taking multivitamin supplements?

     Multivitamins have their use for people with vitamin and mineral deficiencies, but they don't appear to offer many health benefits for the general population.

    If you feel that you could be lacking in certain nutrients, it may be better to look at changing your diet rather than reaching for supplements. If you need help, see your doctor or a dietitian. 

    https://metafact.io/factcheck_answers/2064

    https://www.sciencealert.com/multivitamins-don-t-necessarily-make-y...

  • Dr. Krishna Kumari Challa

    Pufferfish may be carving mysterious ‘crop circles’ near Australia

    The only other known rings are fish nests found 5,500 kilometers away, in Japan

    Japan’s white-spotted pufferfish are renowned for producing complex, ringed patterns in the sand. Now, 5,500 kilometers away in Australia, scientists have discovered what appear to be dozens more of these creations.

    While conducting a marine life survey out on Australia’s North West Shelf near subsea gas infrastructure with an autonomous underwater vehicle, marine ecologist Todd Bond spotted a striking pattern on the seafloor, more than 100 meters deep.  “Immediately, I knew what it was,” recounts Bond, of the University of Western Australia in Perth. Bond and his colleagues continued the survey, ultimately finding nearly two dozen more.

    Until now, these undersea “crop circles” were found only off the coast of Japan. First spotted in the 1990s, it took two decades to solve the mystery of what created them. In 2011, scientists found the sculptors — the diminutive males of what was then a new species of Torquigener pufferfish. The patterns are nests, meticulously plowed over the course of days and decorated with shells to entice females to lay their eggs in the center. 

    https://www.sciencenews.org/article/pufferfish-mysterious-crop-circ...
  • Dr. Krishna Kumari Challa

    ‘Great Adaptations’ unravels mysteries of amazing animal abilities

    Tales of unusual animals — and unusual science — make for an entertaining read

    the mystery behind the mole’s wiggly star-shaped appendage (it helps the subterranean animal sense prey without using sight)

    how “hangry” water shrews execute the fastest documented predatory attack by a mammal and how cockroaches resist becoming zombies during parasitoid wasp attacks (SN: 10/31/18).

    the notion that a tentacled snake (Erpeton tentaculatum) might use the short appendages close to itsmouth to lure in nearby fish, just like snapping turtles dowith their tongues, turned out to be wrong. Instead, the tentacleshelp a snake sense a fish’s position in the water andknow when to attack. What’s more, the snakes have hackedtheir prey’s natural escape reflexes. In a fatal mistake, fishflee in the wrong direction — straight toward a snake’smouth — when duped by a twitch of the snake’s neck rightbefore the predator strikes.

     Tentacled snakes are born knowing how to strike at prey rather than learning through failure you can’t “find enough superlatives to sum up these results.” A fight between a parasitoid wasp and a cockroach is like an “insect rodeo.” The wasp attacks a cockroach’s head in an attempt to lay an egg, but in defense the roach “bucks, jumps, and flails with all its might.”

    https://www.sciencenews.org/article/book-great-adaptations-unravels...

    You can check   Great Adaptations on Amazon.com.

  • Dr. Krishna Kumari Challa

    Restoring 30% of the world's ecosystems in priority areas could stave off extinctions and absorb CO2

    Returning specific ecosystems that have been replaced by farming to their natural state in all continents worldwide would rescue the majority of land-based species of mammals, amphibians and birds under threat of extinction. Such measures would also soak up more than 465 billion tons of carbon dioxide, according to a new report released today. Protecting 30% of the priority areas identified in the study, together with protecting ecosystems still in their natural form, would reduce carbon emissions equivalent to 49% of all the carbon that has built up in our atmosphere over the last two centuries. Some 27 researchers from 12 countries contributed to the report, which assesses forests, grasslands, shrublands, wetlands and arid ecosystems.

    By identifying precisely which destroyed ecosystems worldwide should be restored to deliver biodiversity and climate benefits at a low cost without impact on agricultural production, the study is the first of its kind to provide global evidence that where restoration takes place has the most profound impact on the achievement of biodiversity, climate and food security goals. According to the study, restoration can be 13 times more cost-effective when it takes place in the highest priority locations.

    Global priority areas for ecosystem restoration, Nature (2020). DOI: 10.1038/s41586-020-2784-9

    https://phys.org/news/2020-10-world-ecosystems-priority-areas-stave...

  • Dr. Krishna Kumari Challa

    Scientists home in on the mechanism that protects cells from premature aging

    Molecules that accumulate at the tip of chromosomes are known to play a key role in preventing damage to our DNA. Now, researchers  have unraveled how these molecules home in on specific sections of chromosomes—a finding that could help to better understand the processes that regulate cell survival in aging and cancer.

    Much like the aglet of a shoelace prevents the end of the lace from fraying, stretches of DNA called telomeres form protective caps at the ends of chromosomes. But as cells divide, telomeres become shorter, making the protective cap less effective. Once telomeres get too short, the cell stops dividing. Telomere shortening and malfunction have been linked to cell aging and age-related diseases, including cancer.

    Scientists have known that RNA species called TERRA help to regulate the length and function of telomeres. Discovered in 2007  TERRA belongs to a class of molecules called noncoding RNAs, which are not translated into proteins but function as structural components of chromosomes. TERRA accumulates at chromosome ends, signaling that telomeres should be elongated or repaired.

    However, it was unclear how TERRA got to the tip of chromosomes and remained there. "The telomere  makes up only a tiny bit of the total chromosomal DNA, so the question is 'how does this RNA find its home. By visualizing TERRA molecules under a microscope, the researchers found that a short stretch of the RNA is crucial to bring it to telomeres. Further experiments showed that once TERRA reaches the tip of chromosomes, several proteins regulate its association with telomeres. Among these proteins, one called RAD51 plays a particularly important role. RAD51 is a well-known enzyme that is involved in the repair of broken DNA molecules. The protein also seems to help TERRA stick to telomeric DNA to form a so-called "RNA-DNA hybrid molecule". Scientists thought this type of reaction, which leads to the formation of a three-stranded nucleic acid structure, mainly happened during DNA repair. The new study shows that it can also happen at chromosome ends when TERRA binds to telomeres. The researchers also found that short telomeres recruit TERRA much more efficiently than long telomeres. Although the mechanism behind this phenomenon is unclear, the researchers hypothesize that when telomeres get too short, either due to DNA damage or because the cell has divided too many times, they recruit TERRA molecules. This recruitment is mediated by RAD51, which also promotes the elongation and repair of telomeres. "TERRA and RAD51 help to prevent accidental loss or shortening of telomeres. That's an important function."

    Given the role of telomeres in health and disease, it will be important to see how the newly discovered mechanism—which was deduced from observations in living cells and reproduced in test tubes—is regulated in the very complex cellular environment.

    RAD51-dependent recruitment of TERRA long noncoding RNA to telomeres through R-loops, Nature (2020). DOI: 10.1038/s41586-020-2815-6

    https://phys.org/news/2020-10-scientists-home-mechanism-cells-prema...

  • Dr. Krishna Kumari Challa

    The Great Barrier Reef has lost half its corals

    A new study of the Great Barrier Reef shows populations of its small, medium and large corals have all declined in the past three decades. Scientists  found the number of small, medium and large corals on the Great Barrier Reef has declined by more than 50 percent since the 1990s.

    The decline occurred in both shallow and deeper water, and across virtually all species—but especially in branching and table-shaped corals. These were the worst affected by record-breaking temperatures that triggered mass bleaching in 2016 and 2017.

    Climate change is driving an increase in the frequency of reef disturbances such as marine heatwaves. 'There is no time to lose—we must sharply decrease greenhouse gas emissions ASAP if we want to protect them from more degradation and total loss', the researchers conclude.

    Andreas Dietzel et al, Long-term shifts in the colony size structure of coral populations along the Great Barrier Reef, Proceedings of the Royal Society B: Biological Sciences (2020). DOI: 10.1098/rspb.2020.1432

    https://phys.org/news/2020-10-great-barrier-reef-lost-corals.html?u...

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    Scientists shed new light on viruses' role in coral bleaching

    Scientists  have shown that viral infection is involved in coral bleaching—the breakdown of the symbiotic relationship between corals and the algae they rely on for energy.

    After analyzing the viral metagenomes they found that bleached corals had a higher abundance of eukaryotic viral sequences, and non-bleached corals had a higher abundance of bacteriophage sequences. This gave the researchers the first quantitative evidence of a shift in viral assemblages between coral bleaching states.
    Bacteriophage viruses infect and replicate within bacteria. Eukaryotic viruses infect non-bacterial organisms like animals.
    In addition to having a greater presence of eukaryotic viruses in general, bleached corals displayed an abundance of what are called giant viruses. Known scientifically as nucleocytoplasmic large DNA viruses, or NCLDV, they are complex, double-stranded DNA viruses that can be parasitic to organisms ranging from the single-celled to large animals, including humans.
    Giant viruses have been implicated in coral bleaching. Now scientists were able to generate the first draft genome of a giant virus that might be a factor in bleaching.

    Adriana Messyasz et al, Coral Bleaching Phenotypes Associated With Differential Abundances of Nucleocytoplasmic Large DNA Viruses, Frontiers in Marine Science (2020). DOI: 10.3389/fmars.2020.555474

    https://phys.org/news/2020-10-scientists-viruses-role-coral.html?ut...