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Comment by Dr. Krishna Kumari Challa on October 14, 2020 at 6:21am

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.

Comment by Dr. Krishna Kumari Challa on October 14, 2020 at 6:03am

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.

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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...

Comment by Dr. Krishna Kumari Challa on October 14, 2020 at 5:59am

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...

Comment by Dr. Krishna Kumari Challa on October 14, 2020 at 5:48am

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....

Comment by Dr. Krishna Kumari Challa on October 14, 2020 at 5:37am

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...

Comment by Dr. Krishna Kumari Challa on October 14, 2020 at 5:25am

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...

Comment by Dr. Krishna Kumari Challa on October 13, 2020 at 7:47am

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...

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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...

Comment by Dr. Krishna Kumari Challa on October 13, 2020 at 6:42am

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

Comment by Dr. Krishna Kumari Challa on October 13, 2020 at 6:40am

**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...

Comment by Dr. Krishna Kumari Challa on October 13, 2020 at 6:24am

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...

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