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Comment by Dr. Krishna Kumari Challa on August 16, 2023 at 12:39pm

Source of hidden consciousness in 'comatose' brain injury patients found

 Researchers have identified brain injuries that may underlie hidden consciousness, a puzzling phenomenon in which brain-injured patients are unable to respond to simple commands, making them appear unconscious despite having some level of awareness.

This study suggests that patients with hidden consciousness can hear and comprehend verbal commands, but they cannot carry out those commands because of injuries in brain circuits that relay instructions from the brain to the muscles.

The findings could help physicians more quickly identify brain-injured patients who might have hidden consciousness and better predict which patients are likely to recover with rehabilitation.

Hidden consciousness, also known as cognitive motor dissociation (CMD), occurs in about 15% to 25% of patients with brain injuries stemming from head trauma, brain hemorrhage, or cardiac arrest.

In previous research, researchers found that subtle brainwaves detectable with EEG are the strongest predictor of hidden consciousness and eventual recovery for unresponsive brain-injured patients. But the precise pathways in the brain that become disrupted in this condition were unknown.

Part 1

Comment by Dr. Krishna Kumari Challa on August 16, 2023 at 8:33am

Scientists theorize a hidden phase transition between liquid and a solid

Anything made out of plastic or glass is known as an amorphous material. Unlike many materials that freeze into crystalline solids, the atoms and molecules in amorphous materials never stack together to form crystals when cooled. In fact, although we commonly think of plastic and glass as "solids," they instead remain in a state that is more accurately described as a supercooled liquid that flows extremely slowly.

And although these "glassy dynamic" materials are ubiquitous in our daily lives, how they become rigid at the microscopic scale has long eluded scientists.

Now, researchers  have discovered molecular behavior in supercooled liquids that represents a hidden phase transition between a liquid and a solid.

Their improved understanding applies to ordinary materials like plastics and glass, and could help scientists develop new amorphous materials for use in medical devices, drug delivery, and additive manufacturing.

Specifically, using theory, computer simulations,  and previous experiments, the scientists explained why the molecules in these materials, when cooled, remain disordered like a liquid until taking a sharp turn toward a solid-like state at a certain temperature called the onset temperature—effectively becoming so viscous that they barely move. This onset of rigidity—a previously unknown phase transition—is what separates supercooled from normal liquids.

Any supercooled liquid continuously jumps between multiple configurations of molecules, resulting in localized particle movements known as excitations. In their proposed theory, the researchers treated the excitations in a 2D supercooled liquid as though they were defects in a crystalline solid.

As the supercooled liquid's temperature increased to the onset temperature, they propose that every instance of a bound pair of defects broke apart into an unbounded pair. At precisely this temperature, the unbinding of defects is what made the system lose its rigidity and begin to behave like a normal liquid. "The onset temperature for glassy dynamics is like a melting temperature that 'melts' a supercooled liquid into a liquid. This should be relevant for all supercooled liquids or glassy systems.

The theory and simulations captured other key properties of glassy dynamics, including the observation that, over short periods of time, a few particles moved while the rest of the liquid remained frozen.

Dimitrios Fraggedakis et al, Inherent-state melting and the onset of glassy dynamics in two-dimensional supercooled liquids, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2209144120

Comment by Dr. Krishna Kumari Challa on August 15, 2023 at 9:59am

Changing flies into degradable plastics?

Imagine using insects as a source of chemicals to make plastics that can biodegrade later—with the help of that very same type of bug. That concept is closer to reality than you might expect. Researchers describe their progress to date, including isolation and purification of insect-derived chemicals and their conversion into functional bioplastics, at the fall meeting of the American Chemical Society (ACS).

Researchers have been developing methods for several years to transform natural products—such as glucose obtained from  sugar cane or trees—into degradable, digestible polymers that don't persist in the environment. But those natural products are harvested from resources that are also used for food, fuel, construction and transportation.

So some researchers began searching for alternative sources that wouldn't have these competing applications.

And they thought of using waste products left over from farming black soldier flies. The larvae of these flies contain many proteins and other nutritious compounds, so the immature insects are increasingly being raised for animal feed and to consume wastes. However, the adults have a short life span after their breeding days are over and are then discarded. How about using them instead of useless plastics?

When  researchers examined the dead flies, they determined that chitin is a major component. This nontoxic, biodegradable, sugar-based polymer strengthens the shell, or exoskeleton, of insects and crustaceans. Manufacturers already extract chitin from shrimp and crab shells for various applications, and researchers now  have been applying similar techniques using ethanol rinses, acidic demineralization, basic deproteinization and bleach decolorization to extract and purify it from the insect carcasses.

Fly-sourced chitin powder is probably purer, since it lacks the yellowish colour and clumpy texture of the traditional product. Researchers also note that obtaining chitin from flies could avoid possible concerns over some seafood allergies. Some other researchers isolate chitin or proteins from fly larvae, but this is the first time the use chitin from discarded adult flies, which—unlike the larvae—aren't used for feed.

Harvesting of building blocks from insect feedstocks for transformation into carbohydrate-derived superabsorbent hydrogels, ACS Fall 2023. www.acs.org/meetings/acs-meetings/fall-2023.html

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Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 12:31pm

Videos of snakes eating themselves

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 12:28pm

A Drug For Regrowing Teeth Could Be Available Within The Next Decade

Teeth don't grow back once we become adults: any wear and tear is permanent – as those of us with fillings will know – which is why it's important to keep them as clean and healthy as we can. However, this is something scientists are now looking to change. It's been announced that clinical trials for a potential tooth regrowth treatment are set to begin in July 2024, building on decades of research in the field. If those trials are successful, therapeutic drugs could be available by 2030. A team from the Medical Research Institute at Kitano Hospital in Japan is in charge of the trial, which is targeting people with anodontia, a rare genetic condition that prevents baby teeth and adult teeth from growing in the normal way. The treatment would initially target young children with the condition, but further down the line, the researchers think it could also be used more broadly – with people who have more common dental problems, such as gum disease, for example. Here's how it works: having found a link between a specific gene called USAG-1 and limits on tooth growth in mice, the researchers then moved on to tests that tried to block the expression of USAG-1.An antibody was discovered that could safely block some of the activity of USAG-1 in mice and ferrets without leading to any serious side effects, leading to induced tooth growth. The next step is to see if the same chemical reactions can be controlled in humans. We're talking about potential rather than reality at the moment, but it might be possible to use the new drug to prompt the growth of a third generation of teeth in the mouth, after baby teeth and full-sized adult teeth. As the researchers point out in a recent scientific review, the benefit of the approach is that teeth growth is being triggered in a natural way, through a process known as bone morphogenetic protein (BMP) signaling. Our bodies are naturally doing the work, without any complicated engineering of stem cells required. The team also suggests that advancements in scanning technology (such as mass spectrometry, for example) will make it easier to spot biomarkers indicating the people who will benefit most from the treatment. Anti-USAG-1 antibody treatment in mice is effective for tooth regeneration and can be a breakthrough in treating tooth anomalies in humans," write the researchers.

https://www.nature.com/articles/s41598-021-93256-y

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Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 12:24pm

A Realistic Way to Make Space Habitats From Asteroids

We can build space habitats from asteroids by spinning them fast enough. That's what Professor Adam Frank suggests in a recent paper he co-wrote. In this interview, we discussed the idea, how realistic it is and what technology will be needed to achieve it, what applications it can have and when we can expect something like that.

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 12:18pm

Cancers Protect Themselves Against Their Own Mutations

Tumors overexpress certain genes to survive a growing pile of harmful mutations, a trait that scientists could exploit to target with drugs.

Most cancerous tumors accumulate thousands of potentially protein-damaging mutations over time, yet they mysteriously continue to thrive. Now, a new computational study helps explain how that is possible: Tumors with a large number of mutations upregulate genes that minimize misfolded proteins to protect them from their own mutations.

To reveal that coping mechanism, researchers explored the gene expression of nearly 10,300 human tumors across 33 cancer types catalogued in the Cancer Genome Atlas database.3 They found consistent upregulation of chaperone proteins and the proteasome, which respectively prevent and degrade misfolded proteins. Next, the researchers validated their findings using cell line data from the Cancer Cell Line Encyclopedia. The cell lines showed similar expression patterns, and when the scientists calculated the effect of knocking down the upregulated genes, higher mutational loads correlated with reduced cell viability. These results suggest that the gene upregulation protects tumors.

This discovery signals a general vulnerability in many tumors that could be exploited, for example by using chaperone and proteasome inhibitors. Scientists developed such drugs decades ago, but this new information might help target them to the tumors that will be most vulnerable.

https://elifesciences.org/reviewed-preprints/87301

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 11:29am

Nanoscale 'tattoos' for individual cells could provide early warnings for health problems

Engineers have developed nanoscale tattoos dots and wires that adhere to live cells in a breakthrough that puts researchers one step closer to tracking the health of individual cells. The new technology allows for the first time the placement of optical elements or electronics on live cells with tattoo-like arrays that stick on cells while flexing and conforming to the cells' wet and fluid outer structure. 

They 're talking about putting something like an electronic tattoo on a living object tens of times smaller than the head of a pin. It's the first step towards attaching sensors and electronics on live cells. The structures were able to stick to soft cells for 16 hours even as the cells moved.

The researchers built the tattoos in the form of arrays with gold, a material known for its ability to prevent signal loss or distortion in electronic wiring. They attached the arrays to cells that make and sustain tissue in the human body, called fibroblasts. The arrays were then treated with molecular glues and transferred onto the cells using an alginate hydrogel film, a gel-like laminate that can be dissolved after the gold adheres to the cell. The molecular glue on the array bonds to a film secreted by the cells called the extracellular matrix.

This work has shown we can attach complex nanopatterns to living cells, while ensuring that the cell doesn't die. It's a very important result that the cells can live and move with the tattoos because there's often a significant incompatibility between living cells and the methods engineers use to fabricate electronics.

The researcher's ability to attach the dots and wires in an array form is also crucial. To use this technology to track bioinformation, researchers must be able to arrange sensors and wiring into specific patterns not unlike how they are arranged in electronic chips.

This is an array with specific spacing, not a haphazard bunch of dots. 

Kam Sang Kwok et al, Toward Single Cell Tattoos: Biotransfer Printing of Lithographic Gold Nanopatterns on Live Cells, Nano Letters (2023). DOI: 10.1021/acs.nanolett.3c01960

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 10:46am

Skeletal elements preserve differing evolutionary forces

Human skeletal morphology is highly diverse and varies among individuals and populations around the globe. This diversity is the result of a complex interplay of various evolutionary forces over a long period of time. Evolutionary biologists divide these forces into two distinct processes. A neutral process refers to mutations producing new diversity which, however, offers no direct advantages or disadvantages to the affected individuals. This new diversity then increases or decreases randomly via what is known as genetic drift within a population.

This is contrasted with non-neutral processes, for example, when mutations do affect the fitness of an individual. As a result, the affected individuals have a greater or lesser ability to adapt to environmental factors.

To draw detailed conclusions about underlying genetic kinship only skeletal elements that evolved through neutral processes should be used.

Therefore , researchers should focus on the teeth and skull, whose structures are considered to have evolved primarily through neutral processes. Contrary to earlier assumptions, not all features in the teeth and skull reliably reflect the underlying genetic code; some are much more suitable than others.  Small morphological features on the teeth, such as groove patterns in the crowns, the number and size of cusps, the shape of the roots, and the presence or absence of wisdom teeth, proved to be particularly suitable. 

Researchers obtain the best results, almost identical to a conventional genetic relationship analysis, when they include all features of the skull and teeth. This is also expected, as more skeletal features provide a richer knowledge of underlying genetic information.

Genetic analyses are often constrained by poor DNA preservation. This is commonly the case with very old bones or those that have been exposed to a warm climate. Damaging bones for DNA analyses is also often out of the question in the case of fragile material or rare finds, or due to ethical reasons. In such cases, the non-destructive examination of skulls and teeth is a valuable alternative for tracing past population history and hominin phylogeny in archaeological contexts, for example, or for inferring ancestry profiles in forensic cases. This , therefore, has implications for the scientific community and society at large.

Comment by Dr. Krishna Kumari Challa on August 14, 2023 at 8:01am

Carbon dioxide - not water - triggers explosive volcanoes

Geoscientists have long thought that water  along with shallow magma stored in Earth's crust drives volcanoes to erupt. Now, thanks to newly developed research tools , scientists have learned that gaseous carbon dioxide can trigger explosive eruptions. A new model suggests that basaltic volcanoes, typically located on the interior of tectonic plates, are fed by a deep magma within the mantle, stored about 20 to 30 kilometers below Earth's surface. The research, which offers a clearer picture of our planet's deep internal dynamics and composition, with implications for improving volcanic-hazards planning, was published Aug. 7 in the Proceedings of the National Academy of Sciences. 

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