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Comment by Dr. Krishna Kumari Challa on September 11, 2021 at 9:01am

New technology designed to genetically control disease-spreading mosquitoes

Leveraging advancements in CRISPR-based genetic engineering, researchers have created a new system that restrains populations of mosquitoes that infect millions each year with debilitating diseases.

The new precision-guided sterile insect technique, or pgSIT, alters genes linked to male fertility—creating sterile offspring—and female flight in Aedes aegypti, the mosquito species responsible for spreading wide-ranging diseases including dengue fever, chikungunya and Zika.

pgSIT is a new scalable genetic control system that uses a CRISPR-based approach to engineer deployable mosquitoes that can suppress populations. Males don't transmit diseases so the idea is that as you release more and more sterile males, you can suppress the population without relying on harmful chemicals and insecticides.

pgSIT differs from "gene drive" systems that could suppress disease vectors by passing desired genetic alterations indefinitely from one generation to the next. Instead, pgSIT uses CRISPR to sterilize male mosquitoes and render female mosquitoes, which spread disease, as flightless. The system is self-limiting and is not predicted to persist or spread in the environment, two important safety features that should enable acceptance for this technology.

Suppressing mosquito populations with precision guided sterile males, Nature Communications (2021). DOI: 10.1038/s41467-021-25421-w

https://phys.org/news/2021-09-technology-genetically-disease-spread...

Comment by Dr. Krishna Kumari Challa on September 11, 2021 at 8:57am

New programmable gene editing proteins found outside of CRISPR systems

Within the last decade, scientists have adapted CRISPR systems from microbes into gene editing technology, a precise and programmable system for modifying DNA. Now, scientists at MIT's McGovern Institute and the Broad Institute of MIT and Harvard have discovered a new class of programmable DNA modifying systems called OMEGAs (Obligate Mobile Element Guided Activity), which may naturally be involved in shuffling small bits of DNA throughout bacterial genomes.

These ancient DNA-cutting enzymes are guided to their targets by small pieces of RNA. While they originated in bacteria, they have now been engineered to work in human cells, suggesting they could be useful in the development of gene editing therapies, particularly as they are small (~30% the size of Cas9), making them easier to deliver to cells than bulkier enzymes. The discovery, reported in the journal Science, provides evidence that natural RNA-guided enzymes are among the most abundant proteins on earth, pointing toward a vast new area of biology that is poised to drive the next revolution in genome editing technology.

Han Altae-Tran et al, The widespread IS200/605 transposon family encodes diverse programmable RNA-guided endonucleases, Science (2021). DOI: 10.1126/science.abj6856

https://phys.org/news/2021-09-programmable-gene-proteins-crispr.htm...

Comment by Dr. Krishna Kumari Challa on September 11, 2021 at 8:54am

Research on beards, wads of gum wins 2021 Ig Nobel prizes

Beards aren't just cool and trendy—they might also be an evolutionary development to help protect a man's delicate facial bones from a punch to the face.

That's the conclusion of a trio of scientists from the University of Utah who are among the winners of this year's Ig Nobel prizes, the Nobel Prize spoofs that honor—or maybe dishonor, depending on your point of view—strange scientific discoveries.

The winners of the 31st annual Ig Nobels being announced Thursday included researchers who figured out how to better control cockroaches on U.S. Navy submarines; animal scientists who looked at whether it's safer to transport an airborne rhinoceros upside-down; and a team that figured out just how disgusting that discarded gum stuck to your shoe is.

These sound like  silly studies, but as usual, there was some method to the madness. These findings have implications for a wide range of disciplines, including forensics, contagious disease control, or bioremediation of wasted chewing gum residues.

https://www.improbable.com/2021-ceremony/winners/

https://phys.org/news/2021-09-beards-wads-gum-ig-nobel.html?utm_sou...

Comment by Dr. Krishna Kumari Challa on September 11, 2021 at 6:45am

How Volcanic Eruptions Can Cool Earth? -- Explained!

Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns.

Comment by Dr. Krishna Kumari Challa on September 10, 2021 at 12:03pm

Sim shows how COVID virus infects cells

Comment by Dr. Krishna Kumari Challa on September 10, 2021 at 11:47am

COVID advances win Breakthrough prizes

Techniques that have helped scientists to understand COVID-19 have scooped two out of five of the most lucrative awards in science and.... “These two awards are for research that has had such an impact on the world that they elevate the stature of the Breakthrough Prize,” says chemical biologist Yamuna Krishnan. “They have been saving lives by the millions.” This year’s US$3-million Breakthrough prizes went to:

• Biochemists Katalin Karikó and Drew Weissman, who discovered how to smuggle genetic material called messenger RNA into cells, leading to the development of a new class of vaccine. Karikó recalls the scepticism surrounding her work in the 1990s that led to numerous grant-proposal and paper rejections (including the 2005 paper for which she is now being recognized), and forced her to take a demotion and a pay cut.
• Chemists Shankar Balasubramanian, David Klenerman and Pascal Mayer, who developed the next-generation sequencing technique that has been used to rapidly track variants of the SARS-CoV-2 coronavirus.
• Chemical biologist Jeffrey Kelly, for working out the part that protein misfolding plays in amyloidosis, a disease that can affect the heart and other organs and cause neurodegeneration — and for developing an effective treatment.
• Optical physicists Hidetoshi Katori and Jun Ye, for inventing the optical lattice clock — a device that would lose less than one second over 15 billion years, improving the precision of time measurements by 10,000 times.
• Mathematician Takuro Mochizuki, for extending the understanding of algebraic structures called ‘holonomic D-modules’ — which are related to certain types of differential equation — to deal with points at which the equations under study are not well defined.

https://www.nature.com/articles/d41586-021-02449-y?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on September 10, 2021 at 11:21am

We Asked a NASA Scientist – Do Aliens Exist?

Comment by Dr. Krishna Kumari Challa on September 10, 2021 at 11:17am

Hydraulic jump

Scientists have long recognized that overshooting storm tops of moist air rising into the upper atmosphere can act like solid obstacles that block or redirect airflow. And it's been proposed that waves of moist air flowing over these tops can break and loft water into the stratosphere. But no research to date has explained how all the pieces fit together.

The new modeling suggests the explosion of turbulence in the atmosphere that accompanies plumed storms unfolds through a phenomenon called a hydraulic jump. The same mechanism is at play when rushing winds tumble over mountains and generate turbulence on the downslope side, or when water speeding smoothly down a dam's spillway abruptly bursts into froth upon joining slower-moving water below.

Leonardo DaVinci observed the phenomenon in flowing water as early as the 1500s, and ancient Romans may have sought to limit hydraulic jumps in aqueduct designs. But until now atmospheric scientists have only seen the dynamic induced by solid topography. The new modeling suggests a hydraulic jump can also be triggered by fluid obstacles in the atmosphere made almost entirely of air and which are changing shape every second, miles above the Earth's surface.

The simulations suggest the onset of the jump coincides with a surprisingly rapid injection of water vapor into the stratosphere, upwards of 7000 kilograms per second. That's two to four times higher than previous estimates. Once it reaches the overworld, water may stay there for days or weeks, potentially influencing the amount and quality of sunlight that reaches Earth via destruction of ozone in the stratosphere and warming the planet's surface. "In our simulations that exhibit plumes, water reaches deep into the stratosphere, where it possibly could have more of a long-term climate impact," said co-author Leigh Orf, an atmospheric scientist at the University of Wisconsin-Madison.

According to O'Neill, high-altitude NASA research aircraft have only recently gained the ability to observe the three-dimensional winds at the tops of thunderstorms, and have not yet observed AACP production at close range. "We have the technology now to go verify our modeling results to see if they're realistic," O'Neill said. "That's really a sweet spot in science."

This research was supported by the National Science Foundation and the NASA Precipitation Measurement Mission and Ground Validation program.

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Story Source:

Materials provided by Stanford University. Original written by Josie Garthwaite. Note: Content may be edited for style and length.

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Journal Reference:

1. Morgan E O’Neill, Leigh Orf, Gerald M. Heymsfield, Kelton Halbert. Hydraulic jump dynamics above supercell thunderstorms. Science, 2021; 373 (6560): 1248 DOI: 10.1126/science.abh3857

https://www.sciencedaily.com/releases/2021/09/210909141231.htm

Comment by Dr. Krishna Kumari Challa on September 10, 2021 at 11:16am

Supercell storms and exploding turbulence

The thunderstorms that spawn most tornadoes are known as supercells, a rare breed of storm with a rotating updraft that can hurtle skyward at speeds faster than 150 miles an hour, with enough power to punch through the usual lid on Earth's troposphere, the lowest layer of our atmosphere.

In weaker thunderstorms, rising currents of moist air tend to flatten and spread out upon reaching this lid, called the tropopause, forming an anvil-shaped cloud. A supercell thunderstorm's intense updraft presses the tropopause upward into the next layer of the atmosphere, creating what scientists call an overshooting top. "It's like a fountain pushing up against the next layer of our atmosphere," O'Neill said.

As winds in the upper atmosphere race over and around the protruding storm top, they sometimes kick up streams of water vapor and ice, which shoot into the stratosphere to form the tell-tale plume, technically called an Above-Anvil Cirrus Plume, or AACP.

The rising air of the overshooting top soon speeds back toward the troposphere, like a ball that accelerates downward after cresting aloft. At the same time, air is flowing over the dome in the stratosphere and then racing down the sheltered side.

Using computer simulations of idealized supercell thunderstorms, O'Neill and colleagues discovered that this excites a downslope windstorm at the tropopause, where wind speeds exceed 240 miles per hour. "Dry air descending from the stratosphere and moist air rising from the troposphere join in this very narrow, crazy-fast jet. The jet becomes unstable and the whole thing mixes and explodes in turbulence," O'Neill said. "These speeds at the storm top have never been observed or hypothesized before."

part2

Comment by Dr. Krishna Kumari Challa on September 10, 2021 at 11:16am

Scientists solve mystery of icy plumes that may foretell deadly supercell storms

The most devastating tornadoes are often preceded by a cloudy plume of ice and water vapor billowing above a severe thunderstorm. New research reveals the mechanism for these plumes could be tied to 'hydraulic jumps' -- a phenomenon Leonardo Da Vinci observed more than 500 years ago.

When a cloudy plume of ice and water vapor billows up above the top of a severe thunderstorm, there's a good chance a violent tornado, high winds or hailstones bigger than golf balls will soon pelt the Earth below.

A new Stanford University-led study, published Sept. 10 in Science, reveals the physical mechanism for these plumes, which form above most of the world's most damaging tornadoes.

Previous research has shown they're easy to spot in satellite imagery, often 30 minutes or more before severe weather reaches the ground. "The question is, why is this plume associated with the worst conditions, and how does it exist in the first place? That's the gap that we are starting to fill," said atmospheric scientist Morgan O'Neill, lead author of the new study.

The research comes just over a week after supercell thunderstorms and tornadoes spun up among the remnants of Hurricane Ida as they barreled into the U.S. Northeast, compounding devastation wrought across the region by record-breaking rainfall and flash floods.

Understanding how and why plumes take shape above powerful thunderstorms could help forecasters recognize similar impending dangers and issue more accurate warnings without relying on Doppler radar systems, which can be knocked out by wind and hail -- and have blind spots even on good days. In many parts of the world, Doppler radar coverage is nonexistent.

"If there's going to be a terrible hurricane, we can see it from space. We can't see tornadoes because they're hidden below thunderstorm tops. We need to understand the tops better," said O'Neill, who is an assistant professor of Earth system science at Stanford's School of Earth, Energy & Environmental Sciences (Stanford Earth).

part 1

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