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Comment by Dr. Krishna Kumari Challa on October 8, 2020 at 7:16am

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...

Comment by Dr. Krishna Kumari Challa on October 8, 2020 at 6:44am

**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...

Comment by Dr. Krishna Kumari Challa on October 8, 2020 at 6:36am

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...

Comment by Dr. Krishna Kumari Challa on October 8, 2020 at 6:27am

Extremely rare Higgs boson decay process spotted

The Higgs boson reached overnight fame in 2012 when it was finally discovered in a jumble of other particles generated at CERN's Large Hadron Collider (LHC) in Geneva, Switzerland. The discovery was monumental because the Higgs boson, which had only been theorized about previously, has the special property of endowing other elementary particles with mass. It is also exceedingly rare and difficult to identify in the debris of colliding particles.

Caltech physicists played a major role in the Higgs boson discovery, a result that earned theoretical physicist Peter Higgs a share of the 2013 Nobel Prize in Physics, and now they continue to make significant findings about rare Higgs boson processes.

This summer, for the first time, particle physicists using data collected by the experiment known as the Compact Muon Solenoid (CMS) at the LHC, have found evidence that the Higgs boson decays into a pair of elementary particles called muons. The muon is a heavier version of the electron, and both muons and electrons belong to a class of particles known as fermions, as described in the widely accepted model of particles called the Standard Model. The Standard Model classifies all particles as either fermions or bosons. Generally, fermions are building blocks of all matter, and bosons are the force carriers.

A muon is also what is known as a second-generation particle. First-generation fermion particles such as electrons are the lightest of particles; second- and third-generation particles can decay to become first-generation particles. The new finding represents the first evidence that the Higgs boson interacts with second-generation fermions.

In addition, this result provides further evidence that the decay rate of the Higgs to fermion pairs is proportional to the square of the mass of the fermion. This is a key prediction of the Higgs theory. With more data, the LHC experiments are expected to confirm that indeed the Higgs gives the fundamental particles their mass.

Joseph Lykken et al. The future of the Higgs boson, Physics Today (2013). DOI: 10.1063/PT.3.2212

https://phys.org/news/2020-10-extremely-rare-higgs-boson.html?utm_s...

Comment by Dr. Krishna Kumari Challa on October 8, 2020 at 5:51am

Traveling brain waves help detect hard-to-see objects

Imagine that you're late for work and desperately searching for your car keys. You've looked all over the house but cannot seem to find them anywhere. All of a sudden you realize your keys have been sitting right in front of you the entire time. Why didn't you see them until now?

A team of scientists has uncovered details of the neural mechanisms underlying the perception of objects. They found that patterns of neural signals, called traveling brain waves, exist in the visual system of the awake brain and are organized to allow the brain to perceive objects that are faint or otherwise difficult to see.

They have discovered that faint objects are much more likely to be seen if visualizing the object is timed with the traveling brain waves. The waves actually facilitate perceptual sensitivity, so there are moments in time when you can see things that you otherwise could not. It turns out that these traveling brain waves are an information-gathering process leading to the perception of an object.

They found that the brain's ability to recognize targets was directly related to when and where the traveling brain waves occurred in the visual system: when the traveling waves aligned with the stimulus. There is a spontaneous level of activity in the brain that appears to be regulated by these traveling waves.

Spontaneous travelling cortical waves gate perception in behaving primates, Nature (2020). DOI: 10.1038/s41586-020-2802-y , www.nature.com/articles/s41586-020-2802-y

https://medicalxpress.com/news/2020-10-brain-hard-to-see.html?utm_s...

Comment by Dr. Krishna Kumari Challa on October 8, 2020 at 5:42am

Scientists clarify how the brain separates present from past dangers

A team of neuroscientists has identified processes the brain undergoes to distinguish real and present dangers from those linked to past experiences in mice. The findings have implications for our understanding of post-traumatic stress disorder (PTSD)—an affliction marked by the inability to distinguish between past and present dangers or to recognize "safe" situations.

Memories of a traumatic episode can last for a long time. But we are able to use such memories selectively: to predict and respond to a subsequent, related danger while also recognizing when threats do not exist. This is especially important for survival behaviour in an uncertain environment such as a conflict zone or at times of social unrest.

This has significant implications for memory disorders such as PTSD, where patients have difficulty distinguishing between safety and threat cues.

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Learning to identify and appropriately respond to cues in an uncertain environment is crucial for animal survival, the researchers note. Specifically, cues that reliably predict danger prompt behaviors such as freezing in order to escape detection. However, along with the threat-predicting cues, an uncertain environment can present cues that predict safety—or, specifically, lack of danger. Animals, then, need to respond to the threat-predicting cue with defensive behaviors and, conversely, to safety cues by ceasing a threat response and resuming normal behaviors.

 the scientists sought to identify the cellular molecules, or substrates, for long-term storage of threat and safety-cue-associated memories.

It has been long established that a region of the brain, the amygdala, plays a fundamental role in the processing and storing of emotion-related information. Less understood, however, are the cellular engines and architecture that underlie it—specifically, the identity of cell types that store cue-related information and allow animals to respond appropriately even after considerable time has elapsed after the initial threat exposure.

Also well understood are the formation and consolidation of long-lasting memories, which occur through changes in the cellular landscape of proteins—a dynamic that captures significant features of an event, in part by synthesis of new proteins.

In the new work, the scientists aimed to better understand these mechanisms by disrupting key steps in protein synthesis in specific cell types—a maneuver that would reveal their significance. This procedure allowed the researchers to identify key players in this intricate process.

Amygdala inhibitory neurons as loci for translation in emotional memories, Nature (2020). DOI: 10.1038/s41586-020-2793-8 , www.nature.com/articles/s41586-020-2793-8

https://medicalxpress.com/news/2020-10-scientists-brain-dangers.htm...

Comment by Dr. Krishna Kumari Challa on October 8, 2020 at 5:33am

2 scientists win Nobel chemistry prize for gene-editing tool

The Nobel Prize in chemistry went to two researchers Wednesday for a gene-editing tool that has revolutionized science by providing a way to alter DNA, the code of life—technology already being used to try to cure a host of diseases and raise better crops and livestock.

Emmanuelle Charpentier  and Jennifer A. Doudna  won for developing CRISPR-cas9, a very simple technique for cutting a gene at a specific spot, allowing scientists to operate on flaws that are the root cause of many diseases.

Announcement of the 2020 Nobel Prize in Chemistry

https://phys.org/news/2020-10-nobel-prize-chemistry-awarded-charpen...

Comment by Dr. Krishna Kumari Challa on October 8, 2020 at 5:28am

Quantum heat engine behaviour observed in a qubit

Although many of today's accepted theories of classical thermodynamics predate even the industrial revolution they helped to propel, many open questions remain around how these ideas translate to the level of single quantum systems. In particular, the potential for superposition of states has as yet unexplored implications for thermodynamic behavior. Now, a collaboration of researchers has produced a quantum device that can not only behave analogously to a heat engine and a refrigerator, but also a superposition of both at the same time.

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They came together to examine the behavior of qubits based on impurities in silicon for quantum interferometry before turning their attention to how the behavior of these systems might resemble classical heat engines.

 K. Ono et al. Analog of a quantum heat engine using a single-spin qubit, Physical Review Letters (2020). Accepted manuscript: journals.aps.org/prl/accepted/ … b682605ce40bdae2719c

https://phys.org/news/2020-10-quantum-behaviour-qubit.html?utm_sour...

Comment by Dr. Krishna Kumari Challa on October 7, 2020 at 9:01am

Himalayan glaciers melting because of high-altitude dust

Desert dust from as far away as Saudi Arabia gets picked up by winds that carry it to the snowpack of the Himalayas, where it accelerates glacial warming and snowmelt, scientists say. 

Himalayan glaciers melting because of high-altitude dust

Dust, climate change and air pollution are triple threat to water source for a billion people

https://newsroom.ucla.edu/releases/dust-in-the-wind-is-making-himal...

https://researchnews.cc/news/2886/Himalayan-glaciers-melting-becaus...

Comment by Dr. Krishna Kumari Challa on October 7, 2020 at 8:54am

Study solves an HIV mystery

In some patients with HIV who take medication, the virus still shows up in their blood. A study  has found “repliclones”—large clones of HIV-infected cells that produce infectious virus particles—are to blame.

A patient with HIV who insists they are adhering to the daily medication regimen meant to keep the virus in check, but testing says otherwise. It seems the virus is still showing up in the patient’s blood, which clinicians thought couldn’t happen when the infection is controlled with medication. scientists report that they’ve solved the mystery—and the answer has clinical implications.

In a study  infectious disease researchers show that the issue isn’t nonadherence to medication or resistance to the drugs. Instead, the patients are victims of what the scientists have dubbed “repliclones”—large clones of HIV-infected cells that produce infectious virus particles.

Repliclones can grow large enough and produce enough virus to make it appear that antiretroviral therapy isn’t working completely even when it is.--

In short, rather than the virus infecting new cells, already infected HIV-producing cells are growing into large clones that make and release virus. Current medications for HIV infection block the virus from infecting new cells but don’t affect virus production from cells or clones of cells that are already infected.

HIV replicates by taking over a cell’s machinery and using it to produce more virus, which can then go on to infect other cells. Antiretroviral therapy, which is taken daily, prevents the virus from infecting new cells. So, even though HIV can’t yet be cured, it can be controlled to the point that it isn’t detectable in blood tests.

https://www.upmc.com/media/news/100520-mellors-replicones

https://researchnews.cc/news/2885/Study-solves-an-HIV-mystery#.X31H...

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