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Comment by Dr. Krishna Kumari Challa on March 3, 2022 at 11:27am

Gradual evolution is back: Darwinian theory of gradual process explained in new research

Abrupt shifts in the evolution of animals—short periods of time when an organism rapidly changes size or form—have long been a challenge for theorists including Darwin. Now a newly published research paper supports the idea that even these abrupt changes are underpinned by a gradual directional process of successive incremental changes, as Darwin's theory of evolution assumes.

Published in Nature Communications recently, evolutionary biologists propose a new statistical model which seeks to explain these sudden changes and long periods of stasis that have been seen in the evolutionary history of some species.

Researchers developed a statistical model that reconstructed the body-size changes which occurred throughout the 170-million-year history of more than 2800 mammal species.

The authors found that despite there being periods for some mammals during which abrupt changes in size occur, these occurrences can be understood as 'normal' changes that draw on the natural variability that evolution routinely adds to natural populations.

Part 1

Comment by Dr. Krishna Kumari Challa on March 3, 2022 at 11:18am

Cas9 protein redesigned to make 

Gene editing safer

One of the grand challenges with using CRISPR-based gene editing on humans is that the molecular machinery sometimes makes changes to the wrong section of a host's genome, creating the possibility that an attempt to repair a genetic mutation in one spot in the genome could accidentally create a dangerous new mutation in another.

CRISPR-based gene-editing tools are adapted from naturally occurring systems in bacteria. In nature, a Cas9 protein floats around in the environment, searching for DNA with a very specific sequence of 20 letters, like the X on a pirate map that indicates "dig here." Sometimes, when most of the letters are correct, except those in spots 18 through 20, Cas9 still goes ahead and digs in. This is called a mismatch, and it can have disastrous consequences in gene editing.

But now, scientists  have redesigned a key component of a widely used CRISPR-based gene-editing tool, called Cas9, to be thousands of times less likely to target the wrong stretch of DNA while remaining just as efficient as the original version, making it potentially much safer. The work is described in a paper published today in the journal Nature.

So far, the researchers have demonstrated the use of SuperFi-Cas9 on DNA in test tubes. They're now collaborating with other researchers who plan to test SuperFi-Cas9 for gene editing in living cells. They're also working to develop still safer and more active versions of Cas9.

David Taylor, Structural basis for mismatch surveillance by CRISPR–Cas9, Nature (2022). DOI: 10.1038/s41586-022-04470-1. www.nature.com/articles/s41586-022-04470-1

https://phys.org/news/2022-03-gene-safer-redesigned-cas9-protein.ht...

Comment by Dr. Krishna Kumari Challa on March 3, 2022 at 8:41am

No, you cannot ‘devaccinate’ yourself with snake venom kits, bleach or cupping

Claims you can “devaccinate” yourself have been circulating on social media, another example of extreme and dangerous misinformation about COVID vaccines.

Methods said to remove COVID vaccines from the body include using snake venom extractors or a type of traditional therapy known as “wet cupping”.

If you encounter claims like this online, you need to ask yourself four questions, to figure out whether these claims really are too good to be true.

https://theconversation.com/no-you-cannot-devaccinate-yourself-with...

Comment by Dr. Krishna Kumari Challa on March 2, 2022 at 11:26am

 “Vigyan Sarvatra Pujyate”  = Science is revered everywhere

Comment by Dr. Krishna Kumari Challa on March 2, 2022 at 10:02am

Solar panels developed to pull in water vapour to grow crops in the desert

Using a unique hydrogel, scientists created a solar-driven system that successfully grows spinach by using water drawn from the air while producing electricity. The proof-of-concept design, described March 1 in the journal Cell Reports Physical Science, offers a sustainable, low-cost strategy to improve food and water security for people living in dry-climate regions.

The system, called WEC²P, is composed of a solar photovoltaic panel placed atop a layer of hydrogel, which is mounted on top of a large metal box to condense and collect water. The researchers  developed the hydrogel in their prior research, and the material can effectively absorb water vapour from ambient air and release the water content when heated.

The researchers used the waste heat from solar panels when generating electricity to drive absorbed water out of the hydrogel. The metal box below collects the vapor and condenses the gas into water. Alternatively, the hydrogel increases the efficiency of solar photovoltaic panels by as much as 9% by absorbing the heat and lowering the panels' temperature.

Peng Wang, An Integrated Solar Driven System Produces Electricity with Freshwater and Crops in Arid Regions, Cell Reports Physical Science (2022). DOI: 10.1016/j.xcrp.2022.100781. www.cell.com/cell-reports-phys … 2666-3864(22)00048-0

https://techxplore.com/news/2022-03-solar-panels-vapor-crops.html?u...

Comment by Dr. Krishna Kumari Challa on March 2, 2022 at 9:15am

New epigenetic biomarkers found that potentially predict preterm birth

A signature found in the cheek cells of mothers and fathers of preterm infants may help develop a test to determine whether a pregnancy may end too early. Such a test could help prevent premature births and the many resulting health impacts on infants by alerting medical providers to the need for early intervention measures.

In a study published in Scientific Reports on March 1, researchers documented more than 100 epigenetic biomarkers in mothers of preterm babies that were distinct from mothers of babies carried to term. Fathers had fewer biomarkers but enough to indicate a likely paternal role in preterm birth.

The signature they found was present in all the parents they analyzed. This is likely to lead eventually to a very useful test. They used buccal cells, which are collected by a cheek swab. It's very non-invasive and easy to do.

Epigenetics are molecular factors and processes around DNA that determine how genes behave. While independent of DNA sequence, epigenetic modifications, which can be caused by things such as toxicant exposure, poor nutrition and alcohol use, can also be inherited.

In this study, researchers found that the preterm female babies carried more than 100 of these biomarkers, indicating the propensity to have a preterm baby may be passed down. That transgenerational capacity is also supported by the fact the signature is found in cheek cells. If an epigenetic modification is present in both sperm and ovum, the resulting baby will have that modification present in every cell of their body—including their cheek cells.

 Preterm birth buccal cell epigenetic biomarkers to facilitate preventative medicine, Scientific Reports (2022). DOI: 10.1038/s41598-022-07262-9

https://medicalxpress.com/news/2022-03-epigenetic-biomarkers-potent...

Comment by Dr. Krishna Kumari Challa on March 1, 2022 at 10:57am

What If We Have A Nuclear War?

Comment by Dr. Krishna Kumari Challa on March 1, 2022 at 10:52am

Climate change is outpacing adaptation

Rising greenhouse-gas emissions could soon outstrip the ability of many communities to adapt. A report from the United Nations Intergovernmental Panel on Climate Change (IPCC), authored by more than 270 researchers from 67 countries, finds that the negative impacts of climate change are mounting far faster than.... Many effects are unavoidable and will hit the world’s most vulnerable populations hardest, it warns. “Any further delay in global action on adaptation and mitigation will miss a brief and rapidly closing window of opportunity to secure a livable and sustainable future for all,” says climate scientist and co-author Maarten van Aalst.

Comment by Dr. Krishna Kumari Challa on March 1, 2022 at 10:27am

UN climate report: 'Atlas of human suffering' worse, bigger

Deadly with extreme weather now, climate change is about to get so much worse. It is likely going to make the world sicker, hungrier, poorer, gloomier and way more dangerous in the next 18 years with an "unavoidable" increase in risks, a new United Nations science report says.

The UN Intergovernmental Panel on Climate Change report said Monday that if human-caused global warming isn't limited to just another couple tenths of a degree, an Earth now struck regularly by deadly heat, fires, floods and drought in future decades will degrade in 127 ways, with some being "potentially irreversible."

"The cumulative scientific evidence is unequivocal: Climate change is a threat to human well-being and planetary health," says the major report designed to guide world leaders in their efforts to curb climate change. Delaying cuts in heat-trapping carbon emissions and waiting on adapting to warming's impacts, it warns, "will miss a brief and rapidly closing window of opportunity to secure a liveable and sustainable future for all.

part1

Comment by Dr. Krishna Kumari Challa on March 1, 2022 at 10:12am

Researchers discovered  in 2008 that bdelloid rotifers are very good at capturing foreign genes. What was found now is that rotifers, about 60 million years ago, accidentally captured a bacterial gene that allowed them to introduce a new epigenetic mark that was not there before." This is the first time that a horizontally transferred gene has been shown to reshape the gene regulatory system in a eukaryote.

Horizontally transferred genes are thought to preferentially be operational genes, not regulatory genes. It is hard to imagine how a single, horizontally transferred gene would form a new regulatory system, because the existing regulatory systems are already very complicated.

Somewhere back in time, a piece of bacterial DNA happened to be fused to a piece of eukaryotic DNA. Both of them became joined in the rotifer's genome and they formed a functional enzyme. That's not so easy to do, even in the lab, and it happened naturally. And then this composite enzyme created this amazing regulatory system, and bdelloid rotifers were able to start using it to control all these jumping transposons.

 Bacterial N4-methylcytosine as an epigenetic mark in eukaryotic DNA, Nature Communications (2022).

https://phys.org/news/2022-02-scientists-dna-modification-animals-c...

Part 2

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