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Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 12:45pm

Excess blood sugar promotes clogging of arteries: study

Excess sugar in the blood, the central feature of diabetes, can react with immune proteins to cause myriad changes in the immune system, including inflammatory changes that promote atherosclerosis, according to a new study from scientists at Weill Cornell Medicine and University of Massachusetts Medical School. The study, published March 15 in the journal Immunity, advances the field of diabetes research by revealing molecular pathways through which the disorder may cause other serious health problems for patients. In principle, these newly revealed pathways could be targeted with future diabetes drugs.

Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 12:41pm

The physics of the stuck Suez ship

High winds combined with ship–bank interaction effects might have sent the huge container ship Ever Given into a spin in the shallow waters of the Suez Canal, suggests hydrodynamicist Evert Lataire. The boat has been wedged fast in the essential shipping route since Tuesday. Bank effects occur in restricted navigation areas, where water displaced by a ship has nowhere to go. As a ship passes close to the side of a shallow channel, the water in the gap must speed up, causing the stern to pull into the bank and the bow to be pushed away. In the case of the Ever Given, the effect could have caused the ship to veer into the opposite bank, as shown in this VesselFinder video.

Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 12:36pm

Octopuses, like humans, sleep in two stages

When researchers filmed captive Octopus insularis octopuses sleeping in their tanks, they recorded alternating phases of “quiet sleep”, in which the creatures were pale and still, followed by short spurts of “active sleep”, in which their skin turned darker and stiffened, they moved their eyes, and muscular twitches contracted their suckers. In mammals, birds and perhaps in reptiles, this two-stage sleep pattern is thought to help consolidate memories and clear waste from the brain. Because our last common ancestor with octopuses lived more than 500 million years ago, it seems that the molluscs evolved this sleeping pattern separately, so its function remains unclear.

https://www.sciencemag.org/news/2021/03/octopuses-humans-sleep-two-...

Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 12:29pm

Molecule attacks coronavirus in a novel way

Scientists at the University of Bonn and the caesar research center have isolated a molecule that might open new avenues in the fight against SARS coronavirus 2. The active ingredient binds to the spike protein that the virus uses to dock to the cells it infects. This prevents them from entering the respective cell, at least in the case of model viruses. It appears to do this by using a different mechanism than previously known inhibitors. The researchers therefore suspect that it may also help against viral mutations. The study will be published in the journal Angewandte Chemie but is already available online.

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Differences in snake venom composition raise questions about treatment

Snakebite kills around 58,000 Indians annually, and a majority of snakebites that lead to death or disability are attributed to the 'big four' of Indian snakes—the Russell's viper (Daboia russelii), one of the deadliest snake species in the world, the spectacled cobra (Naja naja), the common krait (Bungarus caeruleus) and the saw-scaled viper (Echis carinatus). Commercial antivenom treatment for snakebite does not always prove effective, and despite the severity of the problem in India, few efforts have been made to understand why this is so.

Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 12:22pm

Cooling homes without warming the planet

As global temperatures are increasing, demand for air conditioners is expected to triple by 2050. The surge will multiply what is already a major source of greenhouse gas emissions: Air conditioning is currently responsible for almost 20 percent of electricity use in buildings around the world.

Now the startup Transaera is working to curb those energy demands with a more efficient air conditioner that uses safer refrigerants to cool homes. The company believes its machine could have one-fifth the impact on the climate when compared to traditional ACs. 

The thing about air conditioning is the basic technology hasn't changed much since it was invented 100 years ago. 

That will change rapidly if Transaera's small team is successful. The company is currently a finalist in a global competition to redesign the air conditioner. The winner of the competition, named the Global Cooling Prize, will get $1 million to commercialize their machines.

At the heart of Transaera's design is a class of highly porous materials called metal organic frameworks, or MOFs, that passively pull moisture from the air as the machine works. MOFs have a lot of potential applications, but the thing that's held them back is unit economics and the inability to make them in a cost-effective way at scale. What Transaera aims to do is be the first to commercialize MOFs at scale and lead the breakthrough that brings MOFs into the public domain.

Most people think air conditioners only cool the air in a space, but they also dry the air they're cooling. Traditional machines use something called an evaporator, a cold coil to pull water out of the air through condensation. The cold coil must be made much colder than the desired temperature in the room in order to collect moisture. Pulling moisture out of the air takes up about half of the electricity used by traditional air conditioners.

Transaera's MOFs passively collect moisture as air enters the system. The machine's waste heat is then used to dry the MOF material for continuous reuse.

https://news.mit.edu/2021/transaera-air-conditioner-0326

https://phys.org/news/2021-03-cooling-homes-planet.html?utm_source=...

Comment by Dr. Krishna Kumari Challa on March 27, 2021 at 11:55am

How microorganisms can help us get to net negative emissions

Many of the common items we use in our everyday lives—from building materials to plastics to pharmaceuticals—are manufactured from fossil fuels. To reduce our reliance on fossil fuels and reduce greenhouse gas emissions, society has increasingly tried turning to plants to make the everyday products we need. For example, corn can be turned into corn ethanol and plastics, lignocellulosic sugars can be turned into sustainable aviation fuels, and paints can be made from soy oil.

But what if plants could be removed from the picture, eliminating the need for water, fertilizer, and land? What if microbes could instead be harnessed to make fuels and other products? And what if these microbes could grow on carbon dioxide, thus simultaneously producing valuable goods while also removing a greenhouse gas from the atmosphere, all in one reactor? 

Scientists have made good progress in turning this technology into reality. A project developed by them project combines biology and electrochemistry to produce complex molecules, all powered by renewable energy. With carbon dioxide as one of the inputs, the system has potential to remove heat-trapping gases from the atmosphere, or in other words, a negative emissions technology (NET).

https://phys.org/news/2021-03-microorganisms-net-negative-emissions...

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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...

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