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Comment by Dr. Krishna Kumari Challa on November 6, 2021 at 9:33am

Lightning Strikes Carve a Deadly Signature Deep Inside The Bones, Scientists Discover

When a body is struck by lightning, a lot of different things happen. For those who do not survive the ordeal, a range of physical evidence is left on their bodies that can identify the cause of death: damage to the skin, including sometimes burn marks, as well as trauma to various organs.

But what if all the tissue decomposes? From the standpoint of forensic scientists who may only have bones to work with, does lightning leave any discernible trace behind on a skeleton?

According to a new study, yes it does.

In previous experiments, Bacci and fellow researchers identified these unique markers in animal bones, noting "extensive micro-fracturing and fragmentation of the bone matrix" in pig bones subjected to high impulse current, simulating the electrical jolt of a lightning bolt.

In that study, the same kind of micro-fracturing was also seen in the bones of a wild giraffe that was killed by a lightning strike, but it remained unclear whether human skeletons exposed to lightning-levels of current would reveal the same gruesome signature.

With the aid of cadavers donated to science, we now have our answer, with the researchers observing similar patterns of micro-fracturing in human bone subjected to the current application, and of a kind that's distinct from purely thermally induced changes to bone (such as bones burnt in a fire).

"[The lightning damage] takes the form of cracks which radiate out from the center of bone cells, or which jump irregularly between clusters of cells. The pattern of trauma is identical even though the micro-structure of human bone is different from animal bone.

Part 1

Comment by Dr. Krishna Kumari Challa on November 6, 2021 at 8:25am

A research  team found that molecules of non-coding RNA are responsible for establishing "compartments" within the nucleus and shepherding in key molecules to precise regions in the genome. Noncoding RNA are molecules that do not encode for proteins, and instead have an array of functions that are often still mysterious to biologists. In the library analogy, non-coding RNA molecules act as the "shelves" that organize different groups of genes and the machinery that interacts with them.

Understanding how genetic material is organized spatially is a crucial part of understanding the basic workings of life. Dysfunction within the nucleus is a hallmark of many diseases, including cancer, neurodegenerative disorders, and others.

The research was made possible by a powerful tool developed in the Guttman laboratory that enables detailed views of the RNA world, called RD-SPRITE (RNA and DNA Split-Pool Recognition of Interactions by Tag Extension). In essence, RD-SPRITE works by tagging molecules of RNA and DNA with miniscule unique barcodes based on their locations; analyzing the barcodes can then tell you which molecules were at which positions within the cell.

 Sofia A. Quinodoz et al, RNA promotes the formation of spatial compartments in the nucleus, Cell (2021). DOI: 10.1016/j.cell.2021.10.014

https://phys.org/news/2021-11-vast-library-cells.html?utm_source=nw...

Part2

Comment by Dr. Krishna Kumari Challa on November 6, 2021 at 8:24am

The vast little library inside your cells

The human genome can be thought of as a massive library, containing over 20,000 different "instruction manuals": your genes. For example, there are genes which contain information to build a brain cell, a skin cell, a white blood cell, and so on. There are even genes that contain information about regulating the genome itself—like books that explain how to organize a library. The ability to regulate gene expression—in other words, the cell's ability to turn various constellations of genes on or off—is the basis of why different cells (such as a muscle cell or a brain cell) have different forms and functions.
In a cellular nucleus, there is over six feet of genetic material packed into a space 50 times smaller than the width of a human hair. How is the "library" in the nucleus organized? When a cell needs to regulate certain genes, how does the cellular machinery find the right ones amongst 20,000 others?
A new study uses a powerful new tool that can peer into the world of the cell's genetic material (DNA and RNA) in order to find answers to these questions.

Part1

Comment by Dr. Krishna Kumari Challa on November 6, 2021 at 8:16am

In their lab, the researchers captured a host of infected and non-infected flies. Males were given a choice of mating with either an infected or non-infected female, and more often than not, chose the one that was infected. This suggested that the fungus was doing something to make the infected female more attractive to the male even though she was dead. In studying the dead females, the researchers found instances of unusual volatile compounds, including some chemicals called sesquiterpenes, which are not normally associated with house flies but have been found to sexually attract many types of insects, including house flies.

Fungus uses zombie female beetles to infect males

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More information: Andreas Naundrup et al, A pathogenic fungus uses volatiles to entice male flies into fatal matings with infected female cadavers, bioRxiv (2021). DOI: 10.1101/2021.10.21.465334

https://phys.org/news/2021-11-fungus-chemicals-male-flies-infected....

part2

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Comment by Dr. Krishna Kumari Challa on November 6, 2021 at 8:15am

A fungus that uses chemicals to trick male flies into mating with infected dead females

A combined team of researchers from the University of Copenhagen and the Swedish University of Agricultural Sciences reports that a certain fungus uses chemicals to trick male flies into mating with infected dead females. They have written a paper describing their findings and have posted it on the bioXiv preprint server.

Prior research has shown that some types of fungus can give insect victims what has become known as summit disease, in which a victim's nervous system is infected and the unwilling creature begins climbing to the highest vantage point possible. Once there, the wings are spread wide and the victim begins spewing spores. In this new effort, the researchers have found a fungus that takes summit disease one step further by having its female victims also emit chemicals that sexually attract males.

In studying the fungus Entomophthora muscae, the researchers found that it was capable of infecting other insects, primarily house flies, with summit disease. Airborne spores land on a female victim and penetrate her skin. Soon, they invade her entire body, including her nervous system and brain. Chemicals produced by the spores incite the female to begin climbing until she reaches the highest possible point, such as a leaf on a tree. Then, she opens her wings and dies. Meanwhile, the fungus covers her body with little spore-filled cannons. At some point, a male happens by, and when he touches her body, the cannons fire, filling the air with spores, ready to infect others in the vicinity.

Part 1

Comment by Dr. Krishna Kumari Challa on November 5, 2021 at 11:05am

Antibiotic resistance outwitted by supercomputers

 Scientists may have made a giant leap in fighting the biggest threat to human health by using supercomputing to keep pace with the impressive ability of diseases to evolve.

A new study by an international team tackled the problem of antibiotic resistance by redesigning existing antibiotics to overcome bacterial resistance mechanisms.

About 700,000 people are estimated to die every year because of antibiotic resistant bacteria, and that number is expected to rise to millions.

Without effective antibiotics, life expectancy is predicted to drop by 20 years.

The race has been on for many years to develop new antibiotics to fight disease faster than a disease can evolve.

Computers have been used in drug design for decades, but this is the first study to use a multi-pronged computer-guided strategy to make a new antibiotic from an existing one which bacteria have outwitted.

The research was published in PNAS.

Antibiotics are one of the pillars of modern medicine and antibiotic resistance is one of the biggest threats to human health. There's an urgent need to develop new ways of fighting ever-evolving bacteria. It's only a matter of time until bacteria develop counterstrategies against our counterstrategies and become resistant to the new antibiotic, so we will have to keep on studying bacterial resistance mechanisms and develop new derivatives accordingly.

The hope of this new work lies in showing that the resistance mechanisms of bacteria can be addressed in a systematic way, allowing science to continually fight back with a computational evolution of new antibiotics.

Researchers developed a strategy to simulate many aspects of a redesigned antibiotic at the same time, including how soluble it is, how effective it is at entering into the bacteria, and how efficient it is at blocking their protein production.

The computational work outlined in the research was done in a matter of weeks on one of the top supercomputers in Europe, but it took the international team several years to verify experimentally that their approach was indeed correct.

Using a computational approach makes the development of new antibiotic derivatives faster and cheaper, and predicting whether a chemical compound is going to be active before it is synthesized also avoids chemical waste. This is an extremely empowering technology.

https://www.port.ac.uk/news-events-and-blogs/news/antibiotic-resist...

https://researchnews.cc/news/9807/Antibiotic-resistance-outwitted-b...

Comment by Dr. Krishna Kumari Challa on November 5, 2021 at 10:25am

https://www.karger.com/Article/Abstract/63018

https://www.pnas.org/content/118/45/e2112494118

https://www.pnas.org/content/118/45/e2112494118

part2

Comment by Dr. Krishna Kumari Challa on November 5, 2021 at 10:02am

Researchers identify bird and reptile 'microchromosomes' once thought to be dust specks on a microscope slide

 Scientists have discovered that tiny 'microchromosomes' in birds and reptiles, initially thought to be specks of dust on the microscope slide, are linked to a spineless animal ancestor that lived 684 million years ago. They prove to be the building blocks of all animal genomes, but underwent "dizzying rearrangement" in mammals, including humans.

A team of researchers made the discovery by lining up the DNA sequence of microchromosomes that huddle together in the cells of birds and reptiles.

When these little microchromosomes were first seen under the microscope, scientists thought they were just specks of dust among the larger bird chromosomes, but they are actually proper chromosomes.

Using advanced DNA sequencing technology, scientists can at last sequence microchromosomes end-to-end.

Researchers lined up these sequences from birds, turtles, snakes and lizards, platypus and humans and compared them. Astonishingly, the microchromosomes were the same across all bird and reptile species. Even more astonishingly, they were the same as the tiny chromosomes of Amphioxus—a little fish-like animal with no backbone that last shared a common ancestor with vertebrates 684 million years ago.

 In marsupial and placental mammals these ancient genetic remnants are split up into little patches on our big, supposedly normal, chromosomes. The exception is the platypus genome, in which the microchomosomes have all fused together into a few large blocks that reflect our oldest mammal ancestor.  the findings highlight the need to rethink how we view the human genome.

Microchromosomes form a compartment in the cell that might help the genes work together.

Rather than being 'normal,' chromosomes of humans and other mammals were puffed up with lots of 'junk DNA' and scrambled in many different ways. The new knowledge helps explain why there is such a large range of mammals with vastly different genomes inhabiting every corner of our planet. 

https://researchnews.cc/news/9809/Researchers-identify-bird-and-rep...

https://theconversation.com/specks-of-dust-on-the-microscope-slide-...

Part1

Comment by Dr. Krishna Kumari Challa on November 5, 2021 at 9:55am

Vascular disease in COVID-19 is not caused by viral infection of blood vessels

Comment by Dr. Krishna Kumari Challa on November 4, 2021 at 12:09pm

Back in the laboratory, Leonards and her collaborators investigated the effects of four illusory patterns on people’s walking experience. Two of the designs, consisting of black-and-white alternating “furrows and ridges” modeled after the undulating pattern in Rossio Square, looked three-dimensional despite being printed on flat surfaces. More than half of the walkers found such designs aversive or uncomfortable to tread on, affecting their stability and even occasionally inducing fear of falling. The discomfort may lie in the mismatch between the sensory and physical characteristics of the walking environment. In nature, surfaces that look bumpy are generally bumpy, but this was not the case for the floor patterns examined in the study—a concern that may extend to a number of human-built environments.

The clue to avoiding the clash of art and accessibility, Leonards says, is to bring people into the planning process directly from the start and think of the project in a human-centered way. “I don’t think that this comes at the cost of aesthetics,” she explains, “but rather allows a far bigger group of people to enjoy beautiful places safely.”

This article was originally published with the title "The Twisted Paths of Perception" in SA Mind 32, 6, 33-34 (November 2021)

doi:10.1038/scientificamericanmind1121-33

https://www.scientificamerican.com/article/the-twisted-paths-of-per...

Part 2

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