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Comment by Dr. Krishna Kumari Challa on November 1, 2021 at 10:10am

Experts name new species of human ancestor

An international team of researchers, led by University of Winnipeg palaeoanthropologist Dr. Mirjana Roksandic, has announced the naming of a new species of human ancestor, Homo bodoensis. This species lived in Africa during the Middle Pleistocene, around half a million years ago, and was the direct ancestor of modern humans.

The Middle Pleistocene (now renamed Chibanian and dated to 774,000–129,000 years ago) is important because it saw the rise of our own species (Homo sapiens) in Africa, our closest relatives, and the Neanderthals (Homo neanderthalensis) in Europe.

However, human evolution during this age is poorly understood, a problem which paleoanthropologists call "the muddle in the middle." The announcement of Homo bodoensis hopes to bring some clarity to this puzzling, but important chapter in human evolution.

 Resolving the "muddle in the middle": The case for Homo bodoensis sp. nov, Evolutionary Anthropology Issues News and Reviews, DOI: 10.1002/EVAN.21929

https://phys.org/news/2021-10-experts-species-human-ancestor.html?u...

Comment by Dr. Krishna Kumari Challa on October 31, 2021 at 12:03pm

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

The SARS-CoV-2 virus does not infect blood vessels, despite the high risk of blood clots to COVID-19 patients, researchers have found.

The researchers found that the cardiovascular complications of COVID-19 are triggered by inflammation caused by infected airway cells. At least 40 per cent of patients that are hospitalised with COVID-19 are at high risk of blood clots, and anti-coagulation therapies are now being routinely used.

There have been many studies attempting to prove whether the virus is infecting cells of the inner blood vessel wall or not.

By conducting the experiments using real, infectious virus rather than fragments of the virus’s spike protein,researchers now can definitively say it is not.

The researchers used UQ’s sophisticated microscopy facilities to track where the virus travelled in the cells and visualise how blood vessels respond to the live virus.
The body’s inflammatory response had a big effect on the cardiovascular system because they work together to fight infection – the blood delivers the immune cells to the site of infection and makes blood clots if the blood vessel is damaged.

When our immune system works well, it clears the virus from our bodies. But sometimes it goes into overdrive and we get an overblown inflammatory response causing complications –in the case of COVID-19, this is often blood clots, when there shouldn’t be any.

Knowing that it is inflammation causing these cardiovascular complications arising from COVID-19 rather than the virus itself will help us develop the right treatments, and a better understanding of how and why these complications arise.

https://onlinelibrary.wiley.com/doi/10.1002/cti2.1350

https://www.uq.edu.au/news/article/2021/10/vascular-disease-covid-1...

https://researchnews.cc/news/9726/Vascular-disease-in-COVID-19-is-n...

Comment by Dr. Krishna Kumari Challa on October 30, 2021 at 12:03pm

The search for people who never get COVID

Scientists have launched a global hunt for people who are genetically resistant to infection with SARS-CoV-2. They hope that identifying the genes protecting these individuals could lead to the development of virus-blocking drugs that not only protect people from COVID-19, but also prevent them from passing on the infection.

Comment by Dr. Krishna Kumari Challa on October 30, 2021 at 10:22am

What is net-zero?

Comment by Dr. Krishna Kumari Challa on October 30, 2021 at 9:11am

Researchers invent chemical reaction that could accelerate drug discovery

Medicines come from chemical reactions, and better chemical reactions lead to better medicines.

Yet, the most popular reaction used in drug discovery, called the amide coupling, makes an inherently unstable amide bond. Because the body excels at metabolizing medication, one of the most important and difficult goals of drug research is to invent metabolically stable molecules, so we can take one pill a day instead of every 15 minutes.

To that end, researchers at the University of Michigan College of Pharmacy hacked the popular amide coupling to produce a carbon-carbon bond instead of an amide. The carbon-carbon bond is the most prevalent bond arrangement in nature and in synthetic drugs, and it's also typically more stable than the amide bond, the study appears online in the Angewandte Chemie International Edition.

The discovery of the carbon-carbon bond-forming reaction opens the door to more stable medicines, and is particularly applicable to biological probes and new medical imaging agents.

The common amide bond is formed by coupling an amine and a carboxylic acid. To form a carbon-carbon bond, researchers identified a catalyst that deaminates the amine and decarboxylates the carboxylic acid, forming a carbon-carbon bond in the process.

Joining an amine and a  carboxylic acid to make a carbon-carbon bond is also advantageous because these reagents are available in the highest diversity, and are typically less expensive than other raw ingredients that could be used to make a carbon-carbon bond.

Timothy Cernak et al, The Formal Cross‐Coupling of Amines and Carboxylic Acids to Form sp3–sp3 Carbon–Carbon Bonds, Angewandte Chemie International Edition (2021). DOI: 10.1002/anie.202112454

https://phys.org/news/2021-10-chemical-reaction-drug-discovery.html...

Comment by Dr. Krishna Kumari Challa on October 30, 2021 at 8:54am

Study finds the SARS-CoV-2 virus can infect the inner ear

Many COVID-19 patients have reported symptoms affecting the ears, including hearing loss and tinnitus. Dizziness and balance problems can also occur, suggesting that the SARS-CoV-2 virus may be able to infect the inner ear.

A new study from MIT and Massachusetts Eye and Ear provides evidence that the virus can indeed infect cells of the inner ear, including hair cells, which are critical for both hearing and balance. The researchers also found that the pattern of infection seen in human inner ear tissue is consistent with the symptoms seen in a study of 10 COVID-19 patients who reported a variety of ear-related symptoms.

The researchers used novel cellular models of the human inner ear that they developed, as well as hard-to-obtain adult human inner ear tissue, for their studies. The limited availability of such tissue has hindered previous studies of COVID-19 and other viruses that can cause hearing loss.

Direct SARS-CoV-2 infection of the human inner ear may underlie COVID-19-associated audiovestibular dysfunction, Communications Medicine, DOI: 10.1038/s43856-021-00044-w

https://medicalxpress.com/news/2021-10-sars-cov-virus-infect-ear.ht...

Comment by Dr. Krishna Kumari Challa on October 30, 2021 at 8:46am

Study finds California condors can have 'virgin births'

 Condors can have "'virgin births," according to a study released recently. 

Researchers with the San Diego Zoo Wildlife Alliance said genetic testing confirmed that two male chicks hatched in 2001 and 2009 from unfertilized eggs were related to their mothers. Neither was related to a male.

The study was published Thursday in the the Journal of Heredity. It's the first report of asexual reproduction in California condors, although parthenogenesis can occur in other species ranging from sharks to honey bees to Komodo dragons.

But in birds, it usually only occurs when females don't have access to males. In this case, each mother condor had previously bred with males, producing 34 chicks, and each was housed with a fertile male at the time they produced the eggs through parthenogenesis.

The researchers said they believe it is the first case of asexual reproduction in any avian species where the female had access to a mate.

These findings now raise questions about whether this might occur undetected in other species too. 

OUP accepted manuscript, Journal Of Heredity (2021). DOI: 10.1093/jhered/esab052

https://phys.org/news/2021-10-california-condors-virgin-births.html...

Comment by Dr. Krishna Kumari Challa on October 29, 2021 at 8:37am

10 UNESCO forests emit more CO2 than they soak up

Sites containing some of the world's most treasured forests, including the Yosemite National Park and Indonesia's Sumatra rainforest, have been emitting more heat-trapping carbon dioxide than they have absorbed in recent years, a U.N.-backed report said.

According to the report released Thursday, factors like logging, wildfires and clearance of land for agriculture are to blame. The excess carbon turns up from just 10 of 257 forests classified among UNESCO World Heritage sites.

The 10 sites that were net sources of carbon from 2001 to 2020 were the Tropical Rainforest in Sumatra; the Río Platano Biosphere Reserve in Honduras; Grand Canyon National Park and Yosemite National Park in the United States: Waterton Glacier International Peace Park in Canada and the U.S.; the Barberton Makhonjwa Mountains in South Africa; Kinabalu Park in Malaysia; the Uvs Nuur Basin in Russia and Mongolia; the Greater Blue Mountains area of Australia; and Morne Trois Pitons National Park in Dominica.

The Switzerland-based International Union for Conservation of Nature and UNESCO, the U.N.'s cultural and educational agency, said their report provides the first-ever assessment of greenhouse gases produced and absorbed in UNESCO-listed forests. The study was based on information collected through on-site monitoring and from satellites.

The study adds to growing signs that human activities and the fallout from climate change —which scientists say has made weather extremes like drought and wildfires more likely—have transformed some natural carbon sinks that suck up CO₂ from the air into net sources of it over the last two decades.

The report's finding that even some of the most iconic and best protected forests, such as those found in World Heritage sites, can actually contribute to climate change is alarming.

This is because of cutting trees and clearing forests , which produce CO2 and  also largely due to a bout of devastating wildfires in these areas in recent years.

https://phys.org/news/2021-10-unesco-forests-emit-co2.html?utm_sour...

Comment by Dr. Krishna Kumari Challa on October 29, 2021 at 8:28am

Technology to produce unbreakable screens

Cracked phone screens could become a thing of the past thanks to breakthrough research.

A team of researchers  have unlocked the technology to produce next-generation composite glass for lighting LEDs and smartphone, television and computer screens.

The findings will enable the manufacture of glass screens that are not only unbreakable but also deliver crystal clear image quality.

The discovery was a huge step forward in perovskite nanocrystal technology as previously, researchers were only able to produce this technology in the bone-dry atmosphere of a laboratory setting. The emitting materials are made from nanocrystals, called lead-halide perovskites.

They can harvest sunlight and concert it into renewable electricity—playing a vital role in low-cost and high-efficiency new generation solar cells and many promising applications like lighting. Unfortunately, these nanocrystals are extremely sensitive to light, heat, air and water—even water vapor in our air would kill the current devices in a matter of minutes. But this team of chemical engineers and material scientists has developed a process to wrap or bind the nanocrystals in porous glass. This process is key to stabilizing the materials, enhancing its efficiency and inhibits the toxic lead ions from leaching out from the materials.

At present QLED or quantum dot light-emitting diode screens are considered the top performer for image display and performance. This research will enable us to improve on this nanocrystal technology by offering stunning picture quality and strength.

Jingwei Hou et al, Liquid-phase sintering of lead halide perovskites and metal-organic framework glasses, Science (2021). DOI: 10.1126/science.abf4460

https://phys.org/news/2021-10-technology-unbreakable-screens.html?u...

Comment by Dr. Krishna Kumari Challa on October 28, 2021 at 8:45am

The Pupil in Your Eye Can Perceive Numerical Information, Not Just Light

You might know that the size of the pupils in our eyes changes depending on how well lit our environment is, but there's more to the story: Scientists have now discovered that the pupil also shifts in size depending on how many objects we're observing.

The more objects in a scene, the bigger the pupil grows, as if to better accommodate everything that it has to look at. This "perceived numerosity" is a simple and automatic reflex, the new research shows.

In a new study, researchers observed the pupil sizes of 16 participants while they looked at pictures of dots. In some of the pictures, the dots were linked together in dumbbell shapes – creating the illusion that there were fewer objects – and pupil size then shrank. This result shows that numerical information is intrinsically related to perception.

As for where this reaction comes from, it's likely to be linked to the need for survival – most species are thought to have a dedicated 'number sense' that enables them to spot enemies in the wild, find food, get back home, and more besides.

When it comes to humans, being able to weigh up numbers is something that seems to appear as soon as a few hours after birth – even if you're terrible at math, you have a built-in aptitude for judging numerosity, and it appears the dilation of our pupils is part of a response to that. When we look around, we spontaneously perceive the form, size, movement and color of a scene. Equally spontaneously, we perceive the number of items before us. This ability, shared with most other animals, is an evolutionary fundamental: it reveals immediately important quantities, such as how many apples there are on the tree, or how many enemies are attacking.

And there's lots more to explore here as well. Our eyes seem to be more sensitive to the number of items we're looking at rather than how they're spaced or arranged, which is another reaction that can be analyzed in future studies.

https://www.nature.com/articles/s41467-021-26261-4

https://www.sciencealert.com/pupil-size-changes-depending-on-how-ma...

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