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Comment by Dr. Krishna Kumari Challa on April 1, 2023 at 10:12am

Scientists observe flattest explosion ever seen in space

An explosion the size of our solar system has baffled scientists, as part of its shape—similar to that of an extremely flat disk—challenges everything we know about explosions in space.

The explosion observed was a bright Fast Blue Optical Transient (FBOT)—an extremely rare class of explosion which is much less common than other explosions, such as supernovas. The first bright FBOT was discovered in 2018 and given the nickname "the cow."

Explosions of stars in the universe are almost always spherical in shape, as the stars themselves are spherical. However, this explosion, which occurred 180 million light years away, is the most aspherical ever seen in space, with a shape like a disk emerging a few days after it was discovered. This section of the explosion may have come from material shed by the star just before it exploded.

It's still unclear how bright FBOT explosions occur, but it's hoped that this observation, published in Monthly Notices of the Royal Astronomical Society, will bring us closer to understanding them.

Justyn R Maund et al, A flash of polarized optical light points to an aspherical 'cow', Monthly Notices of the Royal Astronomical Society (2023). DOI: 10.1093/mnras/stad539

Comment by Dr. Krishna Kumari Challa on April 1, 2023 at 9:42am

There is a distinction in biology between the two ways that animals deploy poisons. There are poisonous animals that produce toxins in their bodies and others that absorb toxins from their surroundings. Like the frogs, the birds belong to the latter category. Both are believed to acquire toxins from what they eat. Beetles containing the toxin have been found in the stomachs of some of the birds. But the source of the toxin itself has yet to be determined.

What makes it possible for these birds to have a toxin in their bodies without themselves being harmed? The researchers studied this with inspiration from poison dart frogs, whose genetic mutations prevent the toxin from keeping their sodium channels open, and thereby preventing cramps.

So, it was natural to investigate whether the birds had mutations in the same genes. Interestingly enough, the answer is yes and no. The birds have mutations in the area that regulates sodium channels, and which we expect gives them this ability to tolerate the toxin, but not in the exact same places as the frogs.

Finding these mutations that can reduce the binding affinity of Batrathotoxin in poisonous birds in similar places as in poison dart frogs, is quite cool. And it showed that in order to adapt to this Batrachotoxin lifestyle, you need some sort of adaptation in these sodium channels".

Therefore, these studies of the birds establish that while their neurotoxin is similar to that of the South American poison dart frogs, the birds developed their resistance and ability to carry it in the bodies independently of the frogs. This is an example of what biologists refer to as convergent evolution.

 Kasun H. Bodawatta et al, Multiple mutations in the Nav1.4 sodium channel of New Guinean toxic birds provide autoresistance to deadly batrachotoxin, Molecular Ecology (2023). DOI: 10.1111/mec.16878

Part 3

Comment by Dr. Krishna Kumari Challa on April 1, 2023 at 9:42am

The two birds that the researchers discovered to be poisonous are the regent whistler (Pachycephala schlegelii), a species that belongs to a family of birds with a wide distribution and easily recognizable song well-known from across the Indo-Pacific region, and the rufous-naped bellbird (Aleadryas rufinucha).

Most people are familiar with South and Central America's iconic poison dart frogs—especially the golden poison frog. These small, brightly colored amphibians can kill a human at the slightest touch. The discovery of the two new poisonous bird species in New Guinea, which carry the same type of toxin in their skin and feathers, demonstrates that the frog toxin is more widespread than once believed.

The poison in these birds' bodies and plumage is called Batrachotoxin. It is an incredibly potent neurotoxin that, in higher concentrations, such as those found in the skin of golden poison frogs, leads to muscle cramps and cardiac arrest nearly immediately after contact.

The bird's toxin is the same type as that found in frogs, which is a neurotoxin that, by forcing sodium channels in skeletal muscle tissue to remain open, can cause violent convulsions and ultimately death.

Though the level of toxicity of the New Guinean birds is less lethal, it may still serve a defensive purpose, but the adaptive significance for the birds is yet uncertain.

The locals aren't fond of spicy food and steer clear of these birds, because, according to them, their meat burns in the mouth like chili. In fact that's how researchers first became aware of them. And the toxin can be felt when holding onto one of them. It feels kind of unpleasant, and hanging on to one for long isn't an appealing option. This could indicate that the poison serves them as a deterrence of those who would want to eat them to some degree.

According to the researchers, the poisonous birds are an expression of an everlasting evolutionary arms race in nature. It starts at the bottom of the food chain with beetles, insects and other invertebrates. Over time, some of these develop toxicity to avoid being eaten. Perhaps they also acquire a particular coloration that may serve as a warning. This in turn allow them to venture from their hideouts beneath logs and rocks.

Part 2

Comment by Dr. Krishna Kumari Challa on April 1, 2023 at 9:35am

 Poisonous Birds: Researchers discover birds with neurotoxin-laden feathers in New Guinea

An expedition into the jungle of New Guinea has resulted in the discovery of two new species of poisonous birds by researchers. The poisonous birds inhabit one of Earth's most pristine rainforests, a place as exotic as no other in the world. Hearing the words poisonous and bird coupled will be an eye-opener for most. But poisonous birds actually exist. And now, more species have been discovered in New Guinea's jungles. These birds contain a neurotoxin that they can both tolerate and store in their feathers.

These birds contain a neurotoxin that they can both tolerate and store in their feathers

Part 1

Comment by Dr. Krishna Kumari Challa on April 1, 2023 at 9:19am

Moths are more efficient pollinators than bees, shows new research

Moths are more efficient pollinators at night than day-flying pollinators such as bees, finds new research, published March 29 in PLOS ONE.

Amid widespread concern about the decline of wild pollinating insects like bees and butterflies,  researchers have discovered that moths are particularly vital pollinators for nature.  They found that 83% of insect visits to bramble flowers were made during the day. While the moths made fewer visits during the shorter summer nights, notching up only 15% of the visits, they were able to pollinate the flowers more quickly.

As a result, the researchers concluded that moths are more efficient pollinators than day-flying insects such as bees, which are traditionally thought of as "hard-working." While day-flying insects have more time available to transfer pollen, moths were making an important contribution during the short hours of darkness.

This research shows that both night-flying and day-flying pollinators need to be protected in order to allow natural ecosystems to flourish.

 Max Anderson et al, Marvellous moths! pollen deposition rate of bramble (Rubus futicosus L. agg.) is greater at night than day, PLOS ONE (2023). DOI: 10.1371/journal.pone.0281810

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

Bacterial ‘syringe’ ferries proteins into cells Researchers have repurposed a bacterium’s molecular ‘syringe’ to deliver proteins, such as the ..., into human cells or the brains of mice. The bacterium Photorhabdus asymbiotica’s injection system usually works only on insect cells. The team modified the structure of the system so that it would recognize other species’ cells and accept payloads including the Cas9 protein, which is five times larger than the syringe’s usual cargo. The method could be a way to administer protein-based drugs and address one of gene editing’s major bottlenecks: delivering the CRISPR–Cas9 system to where it’s needed. Nature Reference: Nature paper

Comment by Dr. Krishna Kumari Challa on March 31, 2023 at 12:08pm

Water is getting scarce. And experts are advising to conserve it ane reduce your water footprint. 

Steps to reduce your water footprint

Meriano offers the following tips for saving water inside and outside the home:

• Fix leakages or dripping immediately from toilets, hot water heaters or other pipes and make sure to turn taps off all the way.
• Showers use less water than baths but if you need to take a soak, don't fill the tub all the way.
• When opportunity arises, choose a new washing machine, toilet, showerhead or dishwasher that uses less water.
• Rainwater that flows down gutters can be collected and used to water plants and gardens.
• Water lawns when it's not hot so water doesn't evaporate, and don't water them on windy days.
• Keeping blades of grass longer can also shelter the roots and cause lawns to need less water.

All health is reliant and dependent on clean water. "You can't have healthy populations without having access to clean water."

Comment by Dr. Krishna Kumari Challa on March 31, 2023 at 12:03pm

Can a solid be a superfluid? Engineering a novel supersolid state from layered 2D materials

A collaboration of Australian and European physicists predict that layered electronic 2D semiconductors can host a curious quantum phase of matter called the "supersolid."

The supersolid is a very counterintuitive phase indeed. It is made up of particles that simultaneously form a rigid crystal and yet at the same time flow without friction since all the particles belong to the same single quantum state.

A solid becomes "super" when its quantum properties match the well-known quantum properties of superconductors. A supersolid simultaneously has two orders, solid and super:

• Solid because of the spatially repeating pattern of particles.
• Super because the particles can flow without resistance.

Although a supersolid is rigid, it can flow like a liquid without resistance.

The new Australia-Europe study predicts that a state could  be engineered in two-dimensional (2D) electronic materials in a semiconductor structure, fabricated with two conducting layers separated by an insulating barrier of thickness d.

One layer is doped with negatively-charged electrons and the other with positively-charged holes. The particles forming the supersolid are interlayer excitons, bound states of an electron and hole tied together by their strong electrical attraction. The insulating barrier prevents fast self-annihilation of the exciton bound pairs. Voltages applied to top and bottom metal "gates" tune the average separation r0 between excitons. The research team predicts that excitons in this structure will form a supersolid over a wide range of layer separations and average separations between the excitons. The electrical repulsion between the excitons can constrain them into a fixed crystalline lattice. "A key novelty is that a supersolid phase with Bose-Einstein quantum coherence appears at layer separations much smaller than the separation predicted for the non-super exciton solid that is driven by the same electrical repulsion between excitons.

In this way, the supersolid pre-empts the non-super exciton solid. At still larger separations, the non-super exciton solid eventually wins, and the quantum coherence collapses.

This is an extremely robust state, readily achievable in experimental setups.

Sara Conti et al, Chester Supersolid of Spatially Indirect Excitons in Double-Layer Semiconductor Heterostructures, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.130.057001

Comment by Dr. Krishna Kumari Challa on March 31, 2023 at 11:12am

In further tests in mice, the researchers showed that they could use the particles to deliver mRNA encoding CRISPR/Cas9 components designed to cut out a stop signal that was genetically encoded into the animals' lung cells. When that stop signal is removed, a gene for a fluorescent protein turns on. Measuring this fluorescent signal allows the researchers to determine what percentage of the cells successfully expressed the mRNA.

After one dose of mRNA, about 40 percent of lung epithelial cells were transfected, the researchers found. Two doses brought the level to more than 50 percent, and three doses up to 60 percent. The most important targets for treating lung disease are two types of epithelial cells called club cells and ciliated cells, and each of these was transfected at about 15 percent.

This means that the cells we were able to edit are really the cells of interest for lung disease. This lipid can enable us to deliver mRNA to the lung much more efficiently than any other delivery system that has been reported so far.

Wen Xue, Combinatorial design of nanoparticles for pulmonary mRNA delivery and genome editing, Nature Biotechnology (2023). DOI: 10.1038/s41587-023-01679-x. www.nature.com/articles/s41587-023-01679-x

Part 2

Comment by Dr. Krishna Kumari Challa on March 31, 2023 at 11:11am

New nanoparticles can perform gene-editing in the lungs

Chemical Engineers have designed a new type of nanoparticle that can be administered to the lungs, where it can deliver messenger RNA encoding useful proteins.

With further development, these particles could offer an inhalable treatment for cystic fibrosis and other diseases of the lung, the researchers say.

This is the first demonstration of highly efficient delivery of RNA to the lungs in mice. Scientists are hopeful that it can be used to treat or repair a range of genetic diseases, including cystic fibrosis.

This is the first demonstration of highly efficient delivery of RNA to the lungs in mice. Researchers are hopeful that it can be used to treat or repair a range of genetic diseases, including cystic fibrosis.

Messenger RNA holds great potential as a therapeutic for treating a variety of diseases caused by faulty genes. One obstacle to its deployment thus far has been difficulty in delivering it to the right part of the body, without off-target effects. Injected nanoparticles often accumulate in the liver, so several clinical trials evaluating potential mRNA treatments for diseases of the liver are now underway. RNA-based COVID-19 vaccines, which are injected directly into muscle tissue, have also proven effective. In many of those cases, mRNA is encapsulated in a lipid nanoparticle—a fatty sphere that protects mRNA from being broken down prematurely and helps it enter target cells.

In their new study, the researchers set out to develop lipid nanoparticles that could target the lungs. The particles are made up of molecules that contain two parts: a positively charged headgroup and a long lipid tail. The positive charge of the headgroup helps the particles to interact with negatively charged mRNA, and it also help mRNA to escape from the cellular structures that engulf the particles once they enter cells.

The lipid tail structure, meanwhile, helps the particles to pass through the cell membrane. The researchers came up with 10 different chemical structures for the lipid tails, along with 72 different headgroups. By screening different combinations of these structures in mice, the researchers were able to identify those that were most likely to reach the lungs.

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