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Comment by Dr. Krishna Kumari Challa on December 10, 2021 at 12:42pm

Scientists solve the grass leaf conundrum

Grass is cut regularly by our mowers and grazed on by cows and sheep, yet continues to grow back. The secret to its remarkable regenerative powers lies in part in the shape of its leaves, but how that shape arises has been a topic of longstanding debate. 

The debate is relevant to our staple crops wheat, rice and maize, because they are members of the grass family with the same type of leaf.

The mystery of grass leaf formation has now been unraveled by a research team.

Flowering plants can be categorized into monocots and eudicots. Monocots, which include the grass family, have leaves that encircle the stem at their base and have parallel veins throughout. Eudicots, which include brassicas, legumes and most common garden shrubs and trees, have leaves that are held away from the stem by stalks, termed petioles, and typically have broad laminas with net-like veins.

In grasses, the base of the leaf forms a tube-like structure, called the sheath. The sheath allows the plant to increase in height while keeping its growing tip close to the ground, protecting it from the blades of lawnmowers or incisors of herbivores. Using recent advances in computational modeling and developmental genetics, the team revisited the problem of grass development. They modeled different hypotheses for how grass leaves grow, and tested the predictions of each model against experimental results. To their surprise, they found that the model based on the 19^th century idea of sheath-petiole equivalence was much more strongly supported than the current view.

The grass study shows how simple modulations of growth rules, based on a common pattern of gene activities, can generate a remarkable diversity of different leaf shapes, without which our gardens and dining tables would be much poorer.

Annis Richardson et al, Evolution of the grass leaf by primordium extension and petiole-lamina remodeling, Science (2021). DOI: 10.1126/science.abf9407. www.science.org/doi/10.1126/science.abf9407

https://phys.org/news/2021-12-scientists-grass-leaf-conundrum.html?...

Comment by Dr. Krishna Kumari Challa on December 9, 2021 at 11:57am

Engineers build in-pipe sewer robot

Scientists from the Division of Mechanical Science and Engineering at Kanazawa University developed a prototype pipe maintenance robot that can unclog and repair pipes with a wide range of diameters. Using a cutting tool with multiple degrees of freedom, the machine is capable of manipulating and dissecting objects for removal. This work may be a significant step forward for the field of sewerage maintenance robots.

Various sewer pipes that are essential to the services of buildings require regular inspection, repair, and maintenance. Current robots that move inside pipes are primarily designed only for visual surveying or inspection. Some robots were developed for maintenance, but they couldn't execute complicated tasks. In-pipe robots that can also clear blockages or perform complex maintenance tasks are highly desirable, especially for pipes that are too narrow for humans to traverse. Now, a team of researchers at Kanazawa University have developed and tested a prototype with these capabilities. 

This robot can help civic and industrial workers by making their job much safer. It can operate in small pipes that humans either cannot access or are dangerous.

Thaelasutt Tugeumwolachot et al, Development of a compact sewerage robot with multi-DOF cutting tool, Artificial Life and Robotics (2021). DOI: 10.1007/s10015-021-00694-y

https://techxplore.com/news/2021-12-in-pipe-sewer-robot.html?utm_so...

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Comment by Dr. Krishna Kumari Challa on December 9, 2021 at 11:54am

A new view of the Universe

Comment by Dr. Krishna Kumari Challa on December 9, 2021 at 11:04am

Plants buy us time to slow climate change—but not enough to stop it

Plants take up carbon dioxide from the atmosphere and convert it into food, forests and other similar ecosystems are considered to be some of the planet's most important carbon sinks.

As human activities cause more carbon dioxide to be emitted into the atmosphere, scientists have debated whether plants are responding by photosynthesizing more and sucking up even more carbon dioxide than they already do—and if so, is it a little or a lot more. Now an international team of researchers led by Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley have used a novel methodology combining remote sensing, machine learning, and terrestrial biosphere models to find that plants are indeed photosynthesizing more, to the tune of 12% higher global photosynthesis from 1982 to 2020. In that same time period, global carbon dioxide concentrations in the atmosphere grew about 17%, from 360 parts per million (ppm) to 420 ppm.

The 12% increase in photosynthesis translates to 14 petagrams of additional carbon taken out of the atmosphere by plants each year, roughly the equivalent of the carbon emitted worldwide from burning fossil fuels in 2020 alone. Not all of the carbon taken out of the atmosphere through photosynthesis is stored in ecosystems, as much is later released back to the atmosphere through respiration, but the study reports a direct link between the increased photosynthesis and increased global carbon storage. The study was published in Nature.

This is a very large increase in photosynthesis, but it's nowhere close to removing the amount of carbon dioxide we're putting into the atmosphere. It's not stopping climate change by any means, but it is helping us slow it down.

Trevor Keenan, A constraint on historic growth in global photosynthesis due to rising CO2 (N&V), Nature (2021). DOI: 10.1038/s41586-021-04096-9. www.nature.com/articles/s41586-021-04096-9

https://phys.org/news/2021-12-climate-changebut.html?utm_source=nwl...

Comment by Dr. Krishna Kumari Challa on December 9, 2021 at 10:55am

Removing a single protein, clusterin, from marathoner mice's plasma largely negated its anti-inflammatory effect on sedentary mice's brains. No other protein the scientists similarly tested had the same effect.

Clusterin, an inhibitor of the complement cascade, was significantly more abundant in the marathoners' blood than in the couch potatoes' blood.

Further experiments showed that clusterin binds to receptors that abound on brain endothelial cells, the cells that line the blood vessels of the brain. These cells are inflamed in the majority of Alzheimer's patients

Research has shown that blood endothelial cells are capable of transducing chemical signals from circulating blood, including inflammatory signals, into the brain.

Tony Wyss-Coray, Exercise plasma boosts memory and dampens brain inflammation via clusterin, Nature (2021). DOI: 10.1038/s41586-021-04183-x. www.nature.com/articles/s41586-021-04183-x

https://medicalxpress.com/news/2021-12-blood-marathoner-mice-boosts...

Part 2

Comment by Dr. Krishna Kumari Challa on December 9, 2021 at 10:54am

Blood from marathoner mice boosts brain function in their couch-potato counterparts

Physical exercise is great for a mouse's brain, and for yours. Numerous studies conducted in mice, humans and laboratory glassware have made this clear. Now, a new study shows it's possible to transfer the brain benefits enjoyed by marathon-running mice to their couch-potato peers.

Researchers have shown that blood from young adult mice that are getting lots of exercise benefits the brains of same-aged, sedentary mice. A single protein in the blood of exercising mice seems largely responsible for that benefit.

The discovery could open the door to treatments that—by taming brain inflammation in people who don't get much exercise—lower their risk of neurodegenerative disease or slow its progression.

Researchers compared blood samples from exercising and sedentary mice of the same age. They showed that transfusions of blood from running mice reduced neuroinflammation in the sedentary mice and improved their cognitive performance. In addition, the researchers isolated a blood-borne protein that appears to play an important role in the anti-neuroinflammatory exercise effect.

Neuroinflammation has been strongly tied to neurodegenerative diseases in humans.  Animal studies have indicated that neuroinflammation precipitates neurodegenerative disorders and that reversing or reducing neuroinflammation can prolong cognitive health

part1

Comment by Dr. Krishna Kumari Challa on December 9, 2021 at 9:18am

Comment by Dr. Krishna Kumari Challa on December 8, 2021 at 11:13am

Scientists Observe Quantum Spin Liquids: A State of Matter We've Never Seen Before

An exotic and totally new state of matter called a quantum spin liquid has been hypothesized for decades, and now scientists have been able to observe it in a laboratory for the first time.

The 'liquid' part refers to electrons that are constantly changing and fluctuating inside a magnetic material at low temperatures. Unlike regular magnets, in this case the electrons don't stabilize or settle into the structured lattice of a solid as they are cooled.

The 'quantum spin' refers to orientation of angular momentum (up or down) carried by particles, which are entangled in pairs with opposing spins. Now that the state has been observed for the first time, it's hoped that the discovery can advance progress in the development of quantum computers.

Normal magnets feature electrons whose spin is orientated in the same direction either up or down, which is what generates magnetism.

In quantum spin liquids, a third electron is introduced, so while two opposing spins will stabilize each other, the spin from the third electron throws out the balance. It creates a 'frustrated' magnet where the spins can't all stabilize in one direction.

To produce their own frustrated lattice pattern, the team used a programmable quantum simulator built in 2017. The simulator uses a quantum computer program to hold atoms in custom shapes using lasers – like squares, triangles, or honeycombs – and can be used to engineer different quantum interactions and processes.

The simulator uses tightly focussed laser beams to arrange atoms individually, and by arranging the atoms of rubidium in a triangle-patterned lattice the researchers were able to produce a frustrated magnet with properties of quantum entanglement – where changes in one atom are matched in a second entangled atom.

The connections between the atoms indicated that a quantum spin liquid had indeed been created.

https://www.science.org/doi/10.1126/science.abi8794

https://www.sciencealert.com/scientists-document-quantum-spin-liqui...

Comment by Dr. Krishna Kumari Challa on December 8, 2021 at 10:58am

The World's Most Dangerous Blood Type

Comment by Dr. Krishna Kumari Challa on December 8, 2021 at 9:52am

No airplane carries oxygen tanks to feed your masks! Then how do you get oxygen?

This video tells how and  also how oxygen masks brought down  a plane

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