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Comment by Dr. Krishna Kumari Challa on April 21, 2022 at 5:25am

There's Something Different About Clouds in Antarctica

Clouds that form in the frosty air above Antarctica are different in the way that water and ice interact inside them, a new study reveals – and that in turn changes how much sunlight they reflect back into space, which is important for climate change models.

Through a combination of modeling, satellite imagery and data collected from flying through the clouds themselves, researchers have identified a process of 'secondary' ice production. This means icy particles collide with supercooled water droplets, freezing and then shattering them, creating many more shards of ice.

The technical term for this sequence of events is Hallett-Mossop rime splintering. It dims the clouds, reducing the amount of sunlight that's reflected back into space, and allowing more of it through into the ocean below. "The Southern Ocean is a massive global heat sink, but its ability to take heat from the atmosphere depends on the temperature structure of the upper ocean, which relates to the cloud cover.

Based on the researchers' calculations, in clouds at temperatures between -3°C and -8°C (26.6°F and 17.6°F), around 10 Watts per square meter of extra energy could reach the ocean from the Sun, enough to significantly change temperatures.

Ice formation inside these clouds is very efficient, and the resulting ice can fall down into the ocean very quickly, too. That rapidly reduces the amount of water in the clouds, and shifts several of their key characteristics from a reflectance point of view.

What's happening inside the clouds also affects their shape, creating further consequences for how well they protect the water underneath.

All these factors need to be weighed up in order to produce climate models that are as accurate as possible.

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021AV000454

Comment by Dr. Krishna Kumari Challa on April 20, 2022 at 11:18am

NASA Beamed a Doctor to The ISS in a World-First 'Holoportation' Achievement

There's never been a house call quite like this. In a first for telepresence communication, a NASA flight surgeon was 'holoported' to the International Space Station (ISS), appearing and conversing as a virtual presence in real time, hundreds of miles above the surface of Earth.

 When NASA flight surgeon Josef Schmid was beamed up to the ISS in October of last year, the illusion was made possible thanks to Microsoft's 'holoportation' technology, which lets users interact with 3D representations of remote participants in real time.

Unlike traditional holographic projections that appear to hover in the air for anybody to see, holoportation requires the use of an augmented reality headset, such as Microsoft's HoloLens technology, for the wearer to be able to perceive (and interact with) the remotely captured individual(s), who are filmed with a multiple-camera setup in their actual location.

In this case, European Space Agency (ESA) astronaut Thomas Pesquet, who was on board the ISS and wearing such a headset, had a two-way conversation with Schmid and members of his medical team, along with Fernando De La Pena Llaca, the CEO of AEXA Aerospace, which develops custom holoportation software (the kind that made this ISS session possible).

https://www.sciencealert.com/nasa-surgeon-beamed-to-international-s...

Comment by Dr. Krishna Kumari Challa on April 20, 2022 at 11:08am

Hypersonic Missiles

https://theconversation.com/how-hypersonic-missiles-work-and-the-un...

Comment by Dr. Krishna Kumari Challa on April 20, 2022 at 10:41am

First US trial of GM mosquitoes

The results are in from the first open-air study of genetically engineered mosquitoes in the United States. The British biotechnology company Oxitec, which ran the experiment, reported in a webinar that its insects behaved as planned: bioengineered male Aedes aegypti mosquitoes hatched, spread and mated with the wild population. A survey of more than 20,000 mosquito eggs laid in the area confirmed that all the females that inherited a deadly gene from a bioengineered dad died before they reached adulthood. More research is needed to discover whether the method successfully suppresses the wild population or achieves its ultimate goal of reducing the transmission of diseases carried by the mosquitoes, such as Zika, dengue, chikungunya and yellow fever.

Comment by Dr. Krishna Kumari Challa on April 20, 2022 at 10:34am

Tumors partially destroyed with sound don't come back

Noninvasive sound technology developed recently by researchers breaks down liver tumors in rats, kills cancer cells and spurs the immune system to prevent further spread—an advance that could lead to improved cancer outcomes in humans.

By destroying only 50% to 75% of liver tumor volume, the rats' immune systems were able to clear away the rest, with no evidence of recurrence or metastases in more than 80% animals.

Even if we don't target the entire tumor, we can still cause the tumor to regress and also reduce the risk of future metastasis. 

Results also showed the treatment stimulated the rats' immune responses, possibly contributing to the eventual regression of the untargeted portion of the tumor and preventing further spread of the cancer.

The treatment, called histotripsy, noninvasively focuses ultrasound waves to mechanically destroy target tissue with millimeter precision. The relatively new technique is currently being used in a human liver cancer trial in the United States and Europe.

Tejaswi Worlikar, Man Zhang, Anutosh Ganguly, Timothy L. Hall, Jiaqi Shi, Lili Zhao, Fred T. Lee, Mishal Mendiratta-Lala, Clifford S. Cho, Zhen Xu. Impact of Histotripsy on Development of Intrahepatic Metastases in a Rodent Liver Tumor Model. Cancers, 2022; 14 (7): 1612 DOI: 10.3390/cancers14071612

Comment by Dr. Krishna Kumari Challa on April 20, 2022 at 10:15am

Researchers obtain functional human blood cells via interspecies chimerism

Interspecies chimerism is a phenomenon of an organism consisting of tissue and genetic information from two different species. Currently, many studies investigate the use of interspecies chimerism with human pluripotent stem cells (hPSCs) to generate functional human cells, tissues or organs in large animals, which is expected to solve the shortage of functional tissues and organs for transplant. However, hPSCs interspecies chimerism faces barriers due to the extremely low chimeric contribution of hPSCs.

Recently, research teams led by Prof. Pan Guangjin and Prof. Lai Liangxue from the Guangzhou Institutes of Biomedicine and Health (GIBH) of the Chinese Academy of Sciences (CAS) made new progress on hPSCs interspecies chimerism. They developed an enhanced hPSCs in interspecies chimerism that allows the obtaining of functional human blood cells through interspecies chimerism technology for the first time. The study is published online in Stem Cell Reports.

The teams discovered that the rapid apoptosis  of hPSCs in the interspecies embryos was mainly due to the growth disadvantage and a "loser" state competing with the host animal stem cells. A new factor MYCN combined with anti-apoptotic gene BCL2 effectively overcame apoptosis of hPSCs and markedly promoted chimerism formation.

Strikingly, the teams isolated live human blood progenitor cells from blood-deficient mice through interspecies chimerism using hPSCs for complementation. The obtained cells can be further cultured and differentiated into different blood cells in dish.

This work presents an important method for understanding the interspecies chimerism barrier using hPSCs. The enhanced hPSCs for interspecies chimerism lays the foundation for acquiring human cells, tissues and organs for transplantation purposes in the future.

Yanling Zhu et al, Generating functional cells through enhanced interspecies chimerism with human pluripotent stem cells, Stem Cell Reports (2022). DOI: 10.1016/j.stemcr.2022.03.009

https://phys.org/news/2022-04-functional-human-blood-cells-interspe...

Comment by Dr. Krishna Kumari Challa on April 19, 2022 at 12:02pm

One step closer to creating new hair follicles

In a new study,  researchers take a unique approach to identify the molecular signals that induce a critical trigger for hair follicle formation and regeneration.

The findings could prove crucial for developing new therapies to re-grow hair—and provide a blueprint for unraveling other mysteries of tissue growth at the cellular level.

This is a decades-old problem that has been unsolvable because formation of the dermal condensate, the signaling center that induces the growth and differentiation of hair follicles, has been difficult to visualize and capture due to how rapidly they form.

Dermal condensates (DCs) are densely-packed clusters of cells, located under the skin's outer layer. DCs act as central commanders of hair follicle activity by sending signals to the skin's outer layer, instructing it to form hair follicles and determining follicle size.

Unraveling the steps that induce DC formation has been a major challenge for researchers, because the process is difficult to track over time and tease apart experimentally. Overcoming this barrier could open the door to effective methods for reproducing DCs to test new drugs for hair loss and to generate hair follicles in 3D culture models.

For this study researchers  took a unique approach to study DCs.

Using single-cell RNA-sequencing data from mouse skin, they designed a computational approach to align a series of single-cell profile "snapshots" to reconstruct the time course of DC development. This provided a roadmap that delineates how an immature dermal cell drives itself to maturity. More importantly, the approach allowed the researchers to investigate the molecular signals that serve as engines in the process. By combining their computational findings with in vivo genetic experiments, they were able to pin down the critical signals involved in DC formation.

One of the signals is known as Wnt and the other is called "sonic hedgehog," or SHH. Both signals are considered essential in the development of many tissue types and play a role in regulating adult tissue homeostasis and regeneration. They are also implicated in pathological states such as cancer when they are aberrantly overactivated.

For the study, the researchers were able to genetically modulate these signals to curtail the speed of DC formation, effectively playing out the DC formation process in slow motion.

This work will help pave the way to developing robust methods for recreating DCs in the laboratory, and for adult hair follicle regeneration.

https://medicine.yale.edu/news-article/one-step-closer-to-creating-...

Comment by Dr. Krishna Kumari Challa on April 19, 2022 at 11:26am

Comment by Dr. Krishna Kumari Challa on April 17, 2022 at 10:09am

Researchers gathered a sample of microbes they knew to be dominated by this methane-slurping archaea, and grew them in an oxygen-lacking environment where methane was the only electron donor.

Near this colony they also placed a metal anode set at zero voltage, effectively creating an electrochemical cell primed to generate a current.

They created a kind of battery with two terminals, where one of these is a biological terminal and the other one is a chemical terminal. 

Researchers grew the bacteria on one of the electrodes, to which the bacteria donate electrons resulting from the conversion of methane. 

After analyzing the conversion of methane to carbon dioxide and measuring fluctuating currents that spiked as high as 274 milliamps per square centimeter, the team deduced a little over a third of the current could be attributed directly to the breaking down of methane.

As far as efficiency goes, 31 percent of the energy in the methane had transformed into electrical power, making it somewhat comparable with some power stations.

Tinkering more with the process could see to the creation of highly efficient living batteries that run on biogas, wringing more spark from every bit of gas and reducing the need for piping methane over long distances. 

https://www.frontiersin.org/articles/10.3389/fmicb.2022.820989/full

https://www.sciencealert.com/these-microbes-breathe-in-methane-and-...

Part 2

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Comment by Dr. Krishna Kumari Challa on April 17, 2022 at 10:06am

Some Microbes Breathe Methane And Turn It Into Electricity in a Weird Living Battery

As far as greenhouse gases go, methane is the quiet villain that could stealthily drag us ever deeper into the climate crisis. In our atmosphere, it is at least 25 times more effective at trapping heat than carbon dioxide.

It's also not that efficient – through burning, less than half of the energy in the natural gas can be converted into electrical power.

In an effort to squeeze more electrons from every puff of methane, researchers in the Netherlands have explored a rather unconventional form of power station – one you'd need a microscope to see.

"In the current biogas installations, methane is produced by microorganisms and subsequently burnt, which drives a turbine, thus generating power. Less than half of the biogas is converted into power, and this is the maximum achievable capacity. But can we  do better using microorganisms?

Scientists found a type of archaea – bacteria-like microbes known for their extraordinary talents of surviving under strange and harsh conditions, including being able to break down methane in environments deprived of oxygen.

This specific type, known as anaerobic methanotrophic (ANME) archaea, manage this metabolic trick by offloading electrons in a chain of electrochemical reactions, employing some kind of metal or metalloid outside of their cells or even donating them to other species in their environment.

First described in 2006, the ANME genus Methanoperedens was found to oxidize methane with a little help from nitrates, making them right at home in the wet bogs of the Netherland's fertilizer-soaked agricultural culverts.

Attempts to pull electrons from this process in microbial fuel cells have resulted in tiny voltages being produced, without any clear confirmation on exactly which processes might be behind the conversion.

If these archaea are to ever show promise as methane-gobbling power cells, they'd really need to churn out a current in a clear, unambiguous fashion.

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