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Comment by Dr. Krishna Kumari Challa on October 16, 2020 at 9:30am

** Need to be in two places at once? It may be possible

https://researchnews.cc/news/3052/Need-to-be-in-two-places-at-once-...

Comment by Dr. Krishna Kumari Challa on October 16, 2020 at 9:23am

How the brain quenches the thirst in different ways ....

After eating a bag of salty potato chips, you probably feel thirsty. And after a long period of exercise, you also probably feel thirsty. However, these two types of thirst are not the same.

In the first example, you would likely reach for water. This is because after eating chips, the concentration of salts and minerals in your blood becomes elevated, which induces a state called osmotic thirst. On the other hand, after exercising, you are likely to reach for Gatorade or some other fluid that can both rehydrate you and replenish electrolytes, minerals that are important for the body functions. This thirst, called hypovolemic thirst, occurs when the volume of your blood is reduced due to fluid loss from sweating.

Now researchers have discovered unique populations of neurons in the mouse brain that separately drive osmotic thirst and hypovolemic thirst. The research exploited a high-throughput and robust technique for mapping neurons that are activated by a specific behaviour or stimulus.

Two brain regions are known to be important in drinking behaviors in mammals, the subfornical organ (SFO) and the organum vasculosum laminae terminalis (OVLT). The Oka laboratory previously demonstrated that each of these regions contains two general categories of neurons: some that induce drinking behavior and others that inhibit it.

The mice were then genetically modified so that the team could activate the osmolality- and hypovolemia-sensitive neurons with pulses of light, through a technique called optogenetics. The researchers showed that the activation of the osmolality-sensitive neurons drove the mice to drink pure water and to avoid salty water. In contrast, when hypovolemia-sensitive neurons were activated, the mice showed an appetite for mineral-rich liquids.
The results show that thirst is a multimodal sensation caused by distinct stimuli. This is an exciting finding because it illustrates how our brain senses internal states using a very similar strategy as peripheral sensory systems such as taste and olfaction

https://www.caltech.edu/about/news/brain-quenches-thirst-different-...

https://researchnews.cc/news/3054/The-brain-quenches-thirst-in-diff...

Comment by Dr. Krishna Kumari Challa on October 16, 2020 at 9:17am

Reviving cells after a heart attack

Researchers unravel the healing mechanisms of extracellular vesicles and demonstrate their healing power on a heart-on-a-chip

Comment by Dr. Krishna Kumari Challa on October 16, 2020 at 9:11am

A hydrogel that could help repair damaged nerves
Injuries to peripheral nerves –– tissues that transmit bioelectrical signals from the brain to the rest of the body –– often result in chronic pain, neurologic disorders, paralysis or disability. Now, researchers have developed a stretchable conductive hydrogel that could someday be used to repair these types of nerves when there’s damage.

Injuries in which a peripheral nerve has been completely severed, such as a deep cut from an accident, are difficult to treat. A common strategy, called autologous nerve transplantation, involves removing a section of peripheral nerve from elsewhere in the body and sewing it onto the ends of the severed one. However, the surgery does not always restore function, and multiple follow-up surgeries are sometimes needed. Artificial nerve grafts, in combination with supporting cells, have also been used, but it often takes a long time for nerves to fully recover.

Now researchers prepared a tough but stretchable conductive hydrogel containing polyaniline and polyacrylamide. The crosslinked polymer had a 3D microporous network that, once implanted, allowed nerve cells to enter and adhere, helping restore lost tissue. They showed that the material could conduct bioelectrical signals through a damaged sciatic nerve removed from a toad. Then, they implanted the hydrogel into rats with sciatic nerve injuries. Two weeks later, the rats’ nerves recovered their bioelectrical properties, and their walking improved compared with untreated rats. Because the electricity-conducting properties of the material improve with irradiation by near-infrared light, which can penetrate tissues, it could be possible to further enhance nerve conduction and recovery in this way, the researchers say.

https://www.acs.org/content/acs/en/pressroom/newsreleases/2020/octo...

https://researchnews.cc/news/3043/A-hydrogel-that-could-help-repair...

Comment by Dr. Krishna Kumari Challa on October 16, 2020 at 8:51am

The Lancet: Herd immunity approaches to COVID-19 control are a 'dangerous fallacy', say authors of open letter

A group of 80 researchers warn that a so-called herd immunity approach to managing COVID-19 by allowing immunity to develop in low-risk populations while protecting the most vulnerable is "a dangerous fallacy unsupported by the scientific evidence".

The open letter, referred to by its authors as the John Snow Memorandum, is published today by The Lancet. It is signed by 80 international researchers (as of publication) with expertise spanning public health, epidemiology, medicine, paediatrics, sociology, virology, infectious disease, health systems, psychology, psychiatry, health policy, and mathematical modelling [1]. The letter will also be launched during the 16th World Congress on Public Health programme 2020.

https://www.eurekalert.org/pub_releases/2020-10/tl-pss101420.php

Comment by Dr. Krishna Kumari Challa on October 16, 2020 at 6:21am

Scientists discovered hidden colours created by a new mechanism

Scientists have stumbled across an unusual way to observe colour that had previously gone unnoticed.

To create the effect, researchers attached a very thin film of one material to another, larger sample. The electric field (an invisible force created by the attraction and repulsion of electrical charges) is very strong where the two materials are connected.

When combined with 'optical interference' (the interaction of different waves of light), a scattering process occurs from the surface of the material, creating bright colors when viewed under different lighting conditions.

Most materials in the world around us appear a certain color because they only absorb part of solar spectrum. For example, leaves on a tree look green to us because they absorb red and blue light.

However, some objects, animals and materials create color a different way, because of the properties they contain. These are known as structural colors.

Structural colors are usually created by diffraction, which happens when rays of light interfere with each other as they reflect off surfaces. Rainbows and colorful oil slicks on top of water are examples of structural color, and the effect is also responsible for the amazing vivid hues of peacock feathers and butterfly wings.

While those phenomena are well established, an unexpected new mechanism for creating similar effects has been uncovered.

The effect is an example of structural color forming because of frequency-selective scattering of light, in which the strength of the electric field and the type of material used is a key factor.

Scientists using  a light microscope to observe gold nanoparticles  unexpectedly noticed that the entire sample was creating a vivid colour visible to the naked eye from all directions.

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To understand it properly, they created thin films which could scatter light and at the same time create diffraction or interference. The system was made using silicon nitride coatings on larger metallic aluminum samples.

Different colors were visible by changing the lighting conditions. Under normal light, the samples looked like a mirror, reflecting back almost all visible light. But turning the overhead lights off and using only one beam of light to illuminate the sample produces vivid, iridescent colors.

Explaining how to easily observe this phenomenon, Eser said: "If you use a flashlight, while in a dark room, to illuminate the sample, the reflected light beam travels away from you to the other side of the room.

"The reflected light never reaches your eyes, only the scattered light can reach your eyes. Whereas when the room light is on, light comes from everywhere on to the sample and therefore you will always see reflected light traveling into your eyes.

"The effect is a previously completely unrecognized curiosity that results in us seeing color. It's fundamentally something different."

 Eser Metin Akinoglu et al. Concealed Structural Colors Uncovered by Light Scattering, Advanced Optical Materials (2020). DOI: 10.1002/adom.202001307

https://phys.org/news/2020-10-dont-hidden-colours-coincidence.html?...

Comment by Dr. Krishna Kumari Challa on October 16, 2020 at 6:08am

Symptoms all in your head—or in your gut? Maybe a little of both.

Anyone who has ever experienced "butterflies in the stomach" before giving a big presentation won't be surprised to learn there is an actual physical connection between their gut and their brain. Neuroscientists and medical professionals call this the "gut-brain-axis" (GBA). A better understanding of the GBA could lead to treatments and cures for neurological mood disorders like depression and anxiety, as well as for a range of chronic auto-immune inflammatory diseases like irritable bowel syndrome (IBS) and rheumatoid arthritis (RA).

Scientists suspect the chemical neurotransmitter serotonin is the biomarker for a range of GBA disorders. Serotonin spurs the nervous system into action via the vagus nerve, the physical connector between the brain and the colon. Generated deep within the lining of the gut, serotonin ultimately influences everything from mood and emotions to sleep, digestion and the secretion of hormones. Its production is in some way affected by the bacterial "microbiome" present in this environment. Researchers hope that creating tools to analyze serotonin's production and dysfunction in the gut microbiome will help unlock the mysteries of GBA-related disorders.

Three new published papers detail the progress in detecting serotonin, assessing its neurological effects, and sensing minute changes to the gut epithelium.

 Pradeep Ramiah Rajasekaran et al, 3D-Printed electrochemical sensor-integrated transwell systems, Microsystems & Nanoengineering (2020). DOI: 10.1038/s41378-020-00208-z

Ashley A. Chapin et al. Electrochemical measurement of serotonin by Au-CNT electrodes fabricated on microporous cell culture membranes, Microsystems & Nanoengineering (2020). DOI: 10.1038/s41378-020-00184-4 A.

A. Chapin, J. Han, T. -W. Ho, J. Herberholz and R. Ghodssi, "A Hybrid Biomonitoring System for Gut-Neuron Communication," in Journal of Microelectromechanical Systems, vol. 29, no. 5, pp. 727-733, Oct. 2020, DOI: 10.1109/JMEMS.2020.3000392.

Pradeep Ramiah Rajasekaran et al. 3D-Printed electrochemical sensor-integrated transwell systems, Microsystems & Nanoengineering (2020). DOI: 10.1038/s41378-020-00208-z

https://phys.org/news/2020-10-symptoms-heador-gut.html?utm_source=n...

Comment by Dr. Krishna Kumari Challa on October 16, 2020 at 5:44am

When feeling the pinch, nuclei instigate cells to escape crowded spaces

The threat of serious deformation triggers a rapid escape reflex that enables cells to move away and squeeze out from tight spaces or crowded tissues.

In a new study  researchers reveal that squeezing a cell to the point where its nucleus starts to stretch triggers the activation of motor proteins which in turn transform the cell's cytoskeleton so that it can flee a packed environment.

Each cell has a nucleus, and each nucleus has a membrane that separates the chromosomes from the rest of the cell. At a rest state, the nuclear membrane is saggy, akin to a loose shopping bag. Now researchers have found that when the nuclear membrane  is squeezed, the wrinkles on its surface iron themselves out, instigating a cascade of events that transform the cytoskeleton and eventually aid the cell in escaping its crowded environment.

The nucleus measures shape changes for cellular proprioception to control dynamic cell behavior, Science (2020). DOI: 10.1126/science.aba2644

Study finds how body cells move within a tissue

https://phys.org/news/2020-10-nuclei-instigate-cells-crowded-spaces...

Comment by Dr. Krishna Kumari Challa on October 15, 2020 at 1:09pm

Science Pinpoints Global Metal Deposit Locations

Miners can find new deposits with less effort

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Decoy Cells Trick SARS-CoV-2, Reduce Cytokines In Vitro

Genetically engineered cells that overproduce ACE2, the receptor the novel coronavirus uses to enter cells, neutralize infection in vitro and mop up inflammatory cytokines in mice.

https://www.the-scientist.com/news-opinion/decoy-cells-trick-sars-c...

Comment by Dr. Krishna Kumari Challa on October 15, 2020 at 1:05pm

Electric and Magnetic Field Treatments Lower Mouse Blood Sugar

**The effects seem to be mediated by a reactive oxygen species in the animals’ livers.

https://www.the-scientist.com/news-opinion/electric-and-magnetic-fi...

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