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Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 11:44am

Direct observations confirm that humans are throwing Earth's energy budget off balance

Earth is on a budget—an energy budget. Our planet is constantly trying to balance the flow of energy in and out of Earth's system. But human activities are throwing that off balance, causing our planet to warm in response.

Radiative energy enters Earth's system from the sunlight that shines on our planet. Some of this energy reflects off of Earth's surface or atmosphere back into space. The rest gets absorbed, heats the planet, and is then emitted as thermal radiative energy the same way that black asphalt gets hot and radiates heat on a sunny day. Eventually this energy also heads toward space, but some of it gets re-absorbed by clouds and greenhouse gases in the atmosphere. The absorbed energy may also be emitted back toward Earth, where it will warm the surface even more.

Adding more components that absorb radiation—like greenhouse gases—or removing those that reflect it—like aerosols—throws off Earth's energy balance, and causes more energy to be absorbed by Earth instead of escaping into space. This is called a radiative forcing, and it's the dominant way human activities are affecting the climate.

Climate modeling predicts that human activities are causing the release of greenhouse gases and aerosols that are affecting Earth's energy budget. Now, a NASA study has confirmed these predictions with direct observations for the first time: radiative forcings are increasing due to human actions, affecting the planet's energy balance and ultimately causing climate change. The paper was published online March 25, 2021, in the journal Geophysical Research Letters.

It was found that  human activities have caused the radiative forcing on Earth to increase by about 0.5 Watts per square meter from 2003 to 2018. The increase is mostly from greenhouse gases emissions from things like power generation, transport and industrial manufacturing. Reduced reflective aerosols are also contributing to the imbalance.

 Ryan J. Kramer et al. Observational evidence of increasing global radiative forcing, Geophysical Research Letters (2021). DOI: 10.1029/2020GL091585

https://phys.org/news/2021-03-humans-earth-energy.html?utm_source=n...

Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 11:38am

The cell signal of death

Scientists have revealed molecular mechanisms involved in eliminating unwanted cells in the body. A nuclear protein fragment released into the cytoplasm activates a plasma membrane protein to display a lipid on the cell surface, signaling other cells to get rid of it. The findings were published in the journal Molecular Cell.

Every day, 10 billion cells die and are engulfed by blood cells called phagocytes. If this didn't happen, dead cells would burst, triggering an auto-immune reaction. It is important to understand how dead cells are eliminated as part of our body's maintenance.

Scientists already know that dead cells display an 'eat me' signal on their surface that is recognized by phagocytes. During this process, lipids are flipped between the inner and outer parts of the cell membrane via a variety of proteins called scramblases, mostly using a protein called Xkr4. It was found that found that a nuclear protein fragment activates Xkr4 to display the 'eat me' signal to phagocytes.

Specifically, the scientists found that cell death signals lead to an enzyme cutting a nuclear protein called XRCC4. A fragment of XRCC4 leaves the nucleus, activating Xkr4, which forms a dimer: the linking of identical pieces into configurations. Both XRCC4 binding and dimer formation are necessary for Xkr4 to ultimately transfer lipids on the cell surface to alert phagocytes.

Xkr4 is only one of the scrambling proteins. Others are activated much faster during cell death. 

Masahiro Maruoka et al, Caspase cleavage releases a nuclear protein fragment that stimulates phospholipid scrambling at the plasma membrane, Molecular Cell (2021). DOI: 10.1016/j.molcel.2021.02.025

https://phys.org/news/2021-03-cell-death.html?utm_source=nwletter&a...

Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 11:27am

How teeth sense the cold

For people with sensitive teeth, eating cold foods is hell. It's a unique kind of pain. It's just excruciating. an international team of scientists have figured out how teeth sense the cold and pinpointed the molecular and cellular players involved. In both mice and humans, tooth cells called odontoblasts contain cold-sensitive proteins that detect temperature drops, the team reports March 26, 2021, in the journal Science Advances. Signals from these cells can ultimately trigger a jolt of pain to the brain.

The work offers an explanation for how one age-old home remedy eases toothaches. The main ingredient in clove oil, which has been used for centuries in dentistry, contains a chemical that blocks the "cold sensor"protein.

Developing drugs that target this sensor even more specifically could potentially eliminate tooth sensitivity to cold. Once you have a molecule to target, there is a possibility of treatment.

 L. Bernal el al., "Odontoblast TRPC5 channels signal cold pain in teeth," Science Advances (2021). advances.sciencemag.org/lookup … .1126/sciadv.abf5567

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Teeth decay when films of bacteria and acid eat away at the enamel, the hard, whitish covering of teeth. As enamel erodes, pits called cavities form. Roughly 2.4 billion people—about a third of the world's population—have untreated cavities in permanent teeth, which can cause intense pain, including extreme cold sensitivity.

https://medicalxpress.com/news/2021-03-teeth-cold.html?utm_source=n...

Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 7:13am

Scientists Created an Artificial Early Embryo From Human Skin Cells

We all know how human reproduction works: sperm meets egg, fertilized egg kicks off its journey, transforms into a human embryo, then becomes a fetus and ultimately a baby.

But what if boy meets girl isn’t the only way?

Last week, two studies in Nature torpedoed the classic narrative of the beginning of life. Two independent teams coaxed ordinary skin cells into a living cluster that resembled a fertilized human egg—and the very first stages of a developing human embryo.

To be clear, the teams did not engineer an artificial embryo that could develop into a viable baby. Rather, they replicated what happens during the first four days after an egg has been fertilized; it develops into a ball of cells called a blastocyst, the first station towards a full-formed baby.

Though they didn’t get beyond the blastocyst stage, both models are by far the most complete replicas of an early human embryo to date. They don’t just contain cells that grow into a baby, but also all of the supporting structures. Within just 10 days inside a Jello-like incubator, the reverse-engineered cells showed traits astonishingly similar to their natural counterparts. For example, the artificial embryos generated cells that form the placenta, which is critical for a viable embryo that could, in theory, develop further or even until birth.

It’s the first complete model of the human early embryo. 

These studies offer a new window into the first days of pregnancy, and may provide insight into previously inexplicable infertility or pregnancy loss without experimenting on human embryos.

Yet the sophistication of these cells is raising concerns. For now, because the artificial embryos differ from natural ones in several ways, scientists don’t expect them to have the ability to grow into complete embryos. As the technologies further refine, however, it may become possible to grow artificial human embryos for longer periods, putting the technology on a collision course with debates about the beginning of life.

The first 14 days of building a human are a mystery.

Scientists know that during a pregnancy, a fertilized egg develops into a blastocyst around day four, and it then implants around day eight. Around this time, something “magical” happens within the blastocyst, such that it churns out cells that eventually develop into the placenta, and others that give rise to a fetus.

The problem? This initial stage is incredibly hard to study. Thus far, scientists have relied on discarded human embryos in the lab—often from IVF outcasts—which can be grown to 13 days according to ethics guidelines

https://singularityhub.com/2021/03/23/scientists-created-an-artific...

Comment by Dr. Krishna Kumari Challa on March 26, 2021 at 12:25pm

A technique to track Earth’s subtle movements with orbiting radars is heating up

Comment by Dr. Krishna Kumari Challa on March 26, 2021 at 11:42am

Meet the zeptosecond, the shortest unit of time ever measured

Scientists have measured the shortest unit of time ever: the time it takes a light particle to cross a hydrogen molecule. 

That time, for the record, is 247 zeptoseconds. A zeptosecond is a trillionth of a billionth of a second, or a decimal point followed by 20 zeroes and a 1. Previously, researchers had dipped into the realm of zeptoseconds; in 2016, researchers reporting in the journal Nature Physics used lasers to measure time in increments down to 850 zeptoseconds. This accuracy is a huge leap from the 1999 Nobel Prize-winning work that first measured time in femtoseconds, which are millionths of a billionths of seconds. 

It takes femtoseconds for chemical bonds to break and form, but it takes zeptoseconds for light to travel across a single hydrogen molecule (H2).

https://www.space.com/zeptosecond-shortest-time-unit-measured.html

Comment by Dr. Krishna Kumari Challa on March 26, 2021 at 9:45am

New Way of Identification of a Place and Tracking

Identification of a place and navigation to reach are two most important things for any traveler. Although Google map has been helping the society at large in many ways, it has some disadvantages. For example, all the postal addresses cannot be identifiable through Google map APP. There is no unique place for identification as popular name of a location has several places. Additionally, it depends wholly on GPS accuracy and may sometimes be away from the desired location by 100 meters. Some of these disadvantages are overcome from our new way of identification of a place. This innovation is simple but its applications are many. It can provide code for any place on the land, water or ice-covered surface of this planet with 8-digit alphanumeric code (TH code). This code is integrated with Google map and implemented in Android based mobile phones and can easily be extended to IOS based Apple mobile phones as well. The accuracy of the code location is about one meter anywhere in the world. To get the code of a location, GPS is not required but internet service is necessary. However, to navigate from one place to the other both GPS and Internet are required. The APP is quite simple to operate and useful to many and has applications at least in ten different sectors. In this present-day Corona virus scenario, the APP is vital to track human beings, goods, medical equipment etc. to reduce human loss, economy loss due to quarantine/lockdown issues .

This app will be very useful in cases of medical emergencies, fire accidents, police security and courier service deliveries.

https://m.scirp.org/papers/100761

Harinarayana, T. , Goyal, P. and Rajendran, N. (2020) New Way of Identification of a Place and Tracking. International Journal of Geosciences, 11, 360-376. doi: 10.4236/ijg.2020.116019.

Comment by Dr. Krishna Kumari Challa on March 26, 2021 at 9:10am

Scientist discovers a new type of 'bi-molecule' with applications for quantum sensors

Researchers found a new type of bi-molecule formed from two nitric oxide (NO) molecules, both in their ground state and in the Rydberg electronic state.

This new type of bi-molecule is the result of the union of two molecules of nitric oxide (NO) whose structure is arranged in such a way that the NO and NO⁺ ion are located in opposite poles. The electron orbits around both, acting like a "glue" that binds the bi-molecule. In addition, its size corresponds to between 200 and 1,000 times that of NO, and its lifetime is long enough to enable its observation and experimental control, as these fragile systems are easily manipulated by means of very weak electric fields.

This type of bi-molecule enables researchers to implement and study chemical reactions at low temperatures from a quantum perspective and facilitates the investigation of intermolecular interactions at large distances, since they coexist at low temperatures.

Rosario González-Férez et al. Ultralong-Range Rydberg Bimolecules, Physical Review Letters (2021). DOI: 10.1103/PhysRevLett.126.043401

https://phys.org/news/2021-03-scientist-bi-molecule-applications-qu...

Comment by Dr. Krishna Kumari Challa on March 26, 2021 at 8:21am

Researchers develop 15-minute test to assess immune response

Researchers from Critical Analytics for Manufacturing Personalized-Medicine (CAMP) have developed a new label-free immune profiling assay that profiles the rapidly changing host immune response in case of infection, in a departure from existing methods that focus on detecting the pathogens themselves, which can often be at low levels within a host. This novel technology presents a host of advantages over current methods, being both much faster, more sensitive and accurate.

In many cases, the main culprit behind disease manifestation, severity of infection, and patient mortality is an overly aggressive host immune response.

For instance, the Spanish Flu pandemic of 1918 resulted in a disproportionately high number of deaths among otherwise healthy young adults. This has been attributed to the now well-studied phenomenon of cytokine storms, which precipitate the rapid release of immune cells and inflammatory molecules and are brought on by a hyper-aggressive host immune response. In a more recent example, cases of severe COVID-19 infection often result in death via sepsis and a dysregulated immune response, while current risk stratification methods based on age and comorbidity remain a significant challenge and can be inaccurate. Moreover, current COVID-19 testing does not prognose the severity of the immune response and can thus lead to inefficient deployment of resources in healthcare settings.

In cases of acute infection, the status of a patient's immune response can often be volatile and may change within minutes. Hence, there exists a pressing need for assays that are able to rapidly and accurately inform on the state of the immune system. This is particularly vital in early triage among patients with acute infection and prediction of subsequent deterioration of disease. In turn, this will better empower medical personnel to make more accurate initial assessments and deliver the appropriate medical response. This can ensure timely intervention in the emergency department (ED) and prevent admission to the intensive care unit (ICU).

The new assay developed by SMART researchers focuses on profiling the rapidly changing host inflammatory response, which in a hyper-aggressive state, can lead to sepsis and death. A 15-minute label-free immune profiling assay from 20 µL of unprocessed blood using unconventional L and inverse-L shaped pillars of DLD microfluidic technology was developed, functioning as a sensitive and quantitative assay of immune cell biophysical signatures in relation to real-time activation levels of WBCs. As WBCs are activated by various internal or external triggers, the assay can sensitively measure both the extent and direction of these changes, which in turn reflect a patient's current immune response state. As such, the new assay developed by SMART researchers is able to accurately and quickly assess patients' immune response states by profiling immune cell size, deformability, distribution, and cell counts.

Significantly, the new assay provides considerable advantages over existing methods of profiling the immune system and its activity. These include measuring leukocyte gene expression, cell-surface biochemical markers, and blood serum cytokine profile.

Kerwin Kwek Zeming et al. Label‐Free Biophysical Markers from Whole Blood Microfluidic Immune Profiling Reveal Severe Immune Response Signatures, Small (2021). DOI: 10.1002/smll.202006123

https://phys.org/news/2021-03-minute-immune-response.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on March 26, 2021 at 7:13am

Scientists find evidence that novel coronavirus infects the mouth's cells

An international team of scientists has found evidence that SARS-CoV-2, the virus that causes COVID-19, infects cells in the mouth. While it's well known that the upper airways and lungs are primary sites of SARS-CoV-2 infection, there are clues the virus can infect cells in other parts of the body, such as the digestive system, blood vessels, kidneys and, as this new study shows, the mouth. The potential of the virus to infect multiple areas of the body might help explain the wide-ranging symptoms experienced by COVID-19 patients, including oral symptoms such as taste loss, dry mouth and blistering. Moreover, the findings point to the possibility that the mouth plays a role in transmitting SARS-CoV-2 to the lungs or digestive system via saliva laden with virus from infected oral cells. A better understanding of the mouth's involvement could inform strategies to reduce viral transmission within and outside the body.

In salivary gland tissue from one of the people who had died, as well as from a living person with acute COVID-19, the scientists detected specific sequences of viral RNA that indicated cells were actively making new copies of the virus—further bolstering the evidence for infection.

Once the team had found evidence of oral tissue infection, they wondered whether those tissues could be a source of the virus in saliva. This appeared to be the case. In people with mild or asymptomatic COVID-19, cells shed from the mouth into saliva were found to contain SARS-CoV-2 RNA, as well as RNA for the entry proteins.

To determine if virus in saliva is infectious, the researchers exposed saliva from eight people with asymptomatic COVID-19 to healthy cells grown in a dish. Saliva from two of the volunteers led to infection of the healthy cells, raising the possibility that even people without symptoms might transmit infectious SARS-CoV-2 to others through saliva.

the study's findings suggest that the mouth, via infected oral cells, plays a bigger role in SARS-CoV-2 infection than previously thought.

Nature Medicine (2021). DOI: 10.1038/s41591-021-01296-8

https://medicalxpress.com/news/2021-03-scientists-evidence-coronavi...

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