Exploring the Heat of the Sun’s Corona

Spacecraft Enters the Sun's Corona for the First Time in History

From:  Center for Astrophysics (Harvard and Smithsonian)

December 14, 2021 -- Cambridge, MA -- A spacecraft launched by NASA has done what was once thought impossible. On April 28, the Parker Solar Probe successfully entered the corona of the Sun — an extreme environment that’s roughly 2 million degrees Fahrenheit.

The historic moment was achieved thanks to a large collaboration of scientists and engineers, including members of the Center for Astrophysics | Harvard & Smithsonian (CfA) who built and monitor a key instrument onboard the probe: the Solar Probe Cup. The cup collects particles from the Sun's atmosphere that helped scientists verify that the spacecraft had indeed crossed into the corona.

"The goal of this entire mission is to learn how the Sun works. We can accomplish this by flying into the solar atmosphere," says Michael Stevens, an astrophysicist at the CfA who helps monitor the cup. "The only way to do that is for the spacecraft to cross the outer boundary, which scientists call the Alfvén point. So, a basic part of this mission is to be able to measure whether or not we crossed this critical point."

The corona is the outermost layer of the Sun's atmosphere where strong magnetic fields bind plasma and prevent turbulent solar winds from escape. The Alfvén point is when solar winds exceed a critical speed and can break free of the corona and the Sun's magnetic fields. Prior to April 28, the spacecraft had been flying just beyond this point.

"If you look at close-up pictures of the Sun, sometimes you'll see these bright loops or hairs that seem to break free from the Sun but then reconnect with it," Stevens explains. "That's the region we've flown into — an area where the plasma, atmosphere and wind are magnetically stuck and interacting with the Sun."

According to data collected by the cup, the spacecraft entered the corona three times on April 28, at one point for up to five hours.  A scientific paper describing the milestone has been accepted for publication in the Physical Review Letters.

CfA astrophysicist Anthony Case, the instrument scientist for the Solar Probe Cup, says the instrument itself is an incredible feat of engineering.

"The amount of light hitting the Parker Solar Probe determines how hot the spacecraft will get," Case explains. "While much of the probe is protected by a heat shield, our cup is one of only two instruments that stick out and have no protection. It's directly exposed to the sunlight and operating at a very high temperature while it's making these measurements; it's literally red-hot, with parts of the instrument at more than 1,800 degrees Fahrenheit [1,000 degrees Celsius], and glowing red-orange."

To avoid degradation, the device is constructed of materials that have high melting points, like tungsten, niobium, molybdenum and sapphire.

But the success of the Parker Solar Probe represents much more than technological innovation. There are many mysteries about Earth’s closest star that scientists are hoping the probe can help solve.

For example, "We don't actually know why the outer atmosphere of the Sun is so much hotter than the Sun itself," Stevens says. "The Sun is 10,000 degrees Fahrenheit [5,500 degrees Celsius], but its atmosphere is about 3.6 million degrees Fahrenheit [2 million degrees Celsius]."

He adds, "We know that the energy comes from the churning magnetic fields bubbling up through the surface of the sun, but we do not know how the Sun's atmosphere absorbs this energy."

In addition, outbursts from the Sun, like solar flares and high-speed solar winds, can have a direct impact on Earth, disrupting power grids and radio communication.

The Parker Solar Probe can help better understand all these phenomena as it continues to orbit the Sun and take measurements and data for scientists to analyze here on Earth.

Case says, "The plasma around the Sun can act as a laboratory that teaches us about processes taking place in almost every astronomical object across the entire universe."

        https://cfa.harvard.edu/news/spacecraft-enters-suns-corona-first-time-history

 

Neuromorphic Electronics Can Be Taught

A combination of organic materials and electronics could open up new possibilities for unconventional future computing systems

From:  Max Planck Institute for Polymer Research

December 13, 2021 -- The processor is the brain of a computer -- an often-quoted phrase. But processors work fundamentally differently than the human brain. Transistors perform logic operations by means of electronic signals. In contrast, the brain works with nerve cells, so-called neurons, which are connected via biological conductive paths, so-called synapses. At a higher level, this signaling is used by the brain to control the body and perceive the surrounding environment. The reaction of the body/brain system when certain stimuli are perceived -- for example, via the eyes, ears or sense of touch -- is triggered through a learning process. For example, children learn not to reach twice for a hot stove: one input stimulus leads to a learning process with a clear behavioral outcome.

Scientists working with Paschalis Gkoupidenis, group leader in Paul Blom's department at the Max Planck Institute for Polymer Research, have now applied this basic principle of learning through experience in a simplified form and steered a robot through a maze using a so-called organic neuromorphic circuit. The work was an extensive collaboration between the Universities of Eindhoven, Stanford, Brescia, Oxford and KAUST.

"We wanted to use this simple setup to show how powerful such 'organic neuromorphic devices' can be in real-world conditions," says Imke Krauhausen, a doctoral student in Gkoupidenis' group and at TU Eindhoven (van de Burgt group), and first author of the scientific paper.

To achieve the navigation of the robot inside the maze, the researchers fed the smart adaptive circuit with sensory signals coming from the environment. The path of maze towards the exit is indicated visually at each maze intersects. Initially, the robot often misinterprets the visual signs, thus it makes the wrong "turning" decisions at the maze intersects and loses the way out. When the robot takes these decisions and follows wrong dead-end paths, it is being discouraged to take these wrong decisions by receiving corrective stimuli. The corrective stimuli, for example when the robot hits a wall, are directly applied at the organic circuit via electrical signals induced by a touch sensor attached to the robot. With each subsequent execution of the experiment, the robot gradually learns to make the right "turning" decisions at the intersects, i. e. to avoid receiving corrective stimuli, and after a few trials it finds the way out of the maze. This learning process happens exclusively on the organic adaptive circuit.

"We were really glad to see that the robot can pass through the maze after some runs by learning on a simple organic circuit. We have shown here a first, very simple setup. In the distant future, however, we hope that organic neuromorphic devices could also be used for local and distributed computing/learning. This will open up entirely new possibilities for applications in real-world robotics, human-machine interfaces and point-of-care diagnostics. Novel platforms for rapid prototyping and education, at the intersection of materials science and robotics, are also expected to emerge." Gkoupidenis says.

                   https://www.sciencedaily.com/releases/2021/12/211213121342.htm

  

USA Tornado outbreak of December 10–11

A deadly late-season tornado outbreak produced catastrophic damage and numerous fatalities across portions of the Southern United States and Ohio Valley from the evening of December 10 to the early morning of December 11, 2021. The event developed as a trough progressed eastward across the United States, interacting with an unseasonably moist and unstable environment across the Mississippi Valley.  Tornado activity began in northeastern Arkansas, before progressing into Missouri, Illinois, Tennessee, and Kentucky.

The most prolific activity was caused by a long-track supercell thunderstorm that produced a family of strong tornadoes, if not a single long-track tornado, across four Mid-Southern states. The nocturnal tornadoes first touched down in northeastern Arkansas, and tracked through the Missouri Bootheel, ripping through towns such as Monette and Leachville, Arkansas, and Hayti and Caruthersville, Missouri; after crossing the Mississippi River into portions of West Tennessee, the storm eventually reached Western Kentucky, where the towns of Mayfield, Benton, Dawson Springs, and Bremen suffered severe to catastrophic damage.

Preliminary estimates suggest the tornado family—identified by some media outlets as the "Quad-State tornado," due to the storm's similar characteristics to the Tri-State tornado that occurred 96 years prior—may have cut a path of up to 250 miles (400 km) across the affected areas; if confirmed to be a single tornado by storm surveys, it would surpass the March 18, 1925, tornado event (which carved a 219-mile [352 km] path across Missouri, Illinois, and Indiana) in terms of path length.  Other tornadic thunderstorms affected portions of eastern Missouri, southern Illinois, western and middle Tennessee, and western and central Kentucky during the late evening into the overnight hours of December 11, including three intense tornadoes that hit Bowling Green, Kentucky; Edwardsville, Illinois; and Defiance, Missouri.

At least 88 people are confirmed to have been killed by the tornadoes, surpassing the Vicksburg, Mississippi tornado of December 5, 1953, which caused 38 fatalities, as the deadliest December tornado event ever recorded in the United States. Unconfirmed estimates suggest that the tornado outbreak may have caused 100 deaths across the four states, with 70 residents feared dead in Mayfield, Kentucky alone, which would make it the deadliest tornado event worldwide since May 2011.  In Kentucky, 74 people have been confirmed dead so far, currently making the outbreak the second-deadliest tornado event in Kentucky history, behind the Louisville-area tornado of March 27, 1890, which caused 76 deaths.

https://en.wikipedia.org/wiki/Tornado_outbreak_of_December_10%E2%80%9311,_2021

 

Magnus Carlsen Retains His Chess Title

The World Chess Championship 2021 was a chess match between the reigning world champion Magnus Carlsen and the challenger Ian Nepomniachtchi to determine the World Chess Champion.  It was held under the auspices of FIDE and played during Expo 2020 at Dubai Exhibition Centre in Dubai, United Arab Emirates, between 24 November and 12 December 2021.  It was originally scheduled for the latter half of 2020, but was postponed until 2021 because of the COVID-19 pandemic.

Carlsen retained his title, winning four games, drawing seven and losing none. After a series of five draws to open the match, Carlsen won a draining 8-hour struggle in Game 6; with 136 moves it was the longest ever game in a World Chess Championship. After a quiet draw in Game 7, Carlsen won three of the last four games, two with the black pieces, to beat his opponent with three games to spare.

             https://en.wikipedia.org/wiki/World_Chess_Championship_2021 

Helping a Robot Through a Maze

From:  Eindhoven University of Technology

December 10, 2021 -- A maze is a popular device among psychologists to assess the learning capacity of mice or rats. But how about robots? Can they learn to successfully navigate the twists and turns of a labyrinth? Now, researchers at the Eindhoven University of Technology (TU/e) in the Netherlands and the Max Planck Institute for Polymer Research in Mainz, Germany, have proven they can. Their robot bases its decisions on the very system humans use to think and act: the brain. The study, which was published in Science Advances, paves the way to exciting new applications of neuromorphic devices in health and beyond.

Machine learning and neural networks have become all the rage in recent years, and quite understandably so, considering their many successes in image recognition, medical diagnosis, e-commerce and many other fields. Still though, this software-based approach to machine intelligence has its drawbacks, not least because it consumes so

Mimicking the human brain

This power issue is one of the reasons that researchers have been trying to develop computers that are much more energy efficient. And to find a solution many are finding inspiration in the human brain, a thinking machine unrivalled in its low power consumption due to how it combines memory and processing.

Neurons in our brain communicate with one another through so-called synapses, which are strengthened each time information flows through them. It is this plasticity that ensures that humans remember and learn.

"In our research, we have taken this model to develop a robot that is able to learn to move through a labyrinth," explains Imke Krauhausen, PhD student at the department of Mechanical Engineering at TU/e and principal author of the paper.

"Just as a synapse in a mouse brain is strengthened each time it takes the correct turn in a psychologist's maze, our device is 'tuned' by applying a certain amount of electricity. By tuning the resistance in the device, you change the voltage that control the motors. They in turn determine whether the robot turns right or left."

So how does it work?

The robot that Krauhausen and her colleagues used for their research is a Mindstorms EV³, a robotics kit made by Lego. Equipped with two wheels, traditional guiding software to make sure it can follow a line, and a number of reflectance and touch sensors, it was sent into a 2 m² large maze made up out of black-lined hexagons in a honeycomb-like pattern.

The robot is programmed to turn right by default. Each time it reaches a dead end or diverges from the designated path to the exit (which is indicated by visual cues), it is told to either return or turn left. This corrective stimulus is then remembered in the neuromorphic device for the next effort.

"In the end, it took our robot 16 runs to find the exit successfully," says Krauhausen. "And, what's more, once it has learned to navigate this specific route (target path 1), it can navigate any other path that it is given in one go (target path 2). So, the knowledge it has acquired is generalizable."

Part of the success of the robot's ability to learn and exit the maze lies in the unique integration of sensors and motors, according to Krauhausen, who cooperated closely with the Max Planck Institute for Polymer Research in Mainz for this research. "This sensorimotor integration, in which sense and movement reinforce one another, is also very much how nature operates, so this is what we tried to emulate in our robot."

Smart polymers

Another clever thing about the research is the organic material used for the neuromorphic robot. This polymer (known as p(g2T-TT)) is not only stable, but it also is able to 'retain' a large part of the specific states in which it has been tuned during the various runs through the labyrinth. This ensures that the learned behaviour 'sticks', just like neurons and synapses in a human brain remember events or actions.

The use of polymer instead of silicon in the field of neuromorphic computing was pioneered by Paschalis Gkoupidenis of the Max Planck Institute for Polymer Research in Mainz and Yoeri van de Burgt of TU/e, both co-authors of the paper.

In their research (dating from 2015 and 2017), they proved that the material can be tuned in a much larger range of conduction than inorganic materials, and that it is able to 'remember' or store learned states for extended periods. Since then, organic devices have become a hot topic in the field of hardware-based artificial neural networks.

Bionic hands

Polymeric materials also have the added advantage that they can be used in numerous biomedical applications. "Because of their organic nature, these smart devices can in principle be integrated with actual nerve cells. Say you lost your arm during an injury. Then you could potentially use these devices to link your body to a bionic hand," says Krauhausen.

Another promising application of organic neuromorphic computing lies in small so-called edge computing devices where data from sensors is processed locally outside of the cloud. Van de Burgt: "This is where I see our devices going in the future, our materials will be very useful because they are easy to tune, use much less power, and are cheap to make."

So will neuromorphic robots one day be able to play a soccer game, just like TU/e's soccer robots?

Krauhausen: "In principle, that is certainly possible. But there's a long way to go. Our robots still rely partly on traditional software to move around. And for the neuromorphic robots to execute really complex tasks, we need to build neuromorphic networks in which many devices work together in a grid. That's something that I will be working on in the next phase of my PhD research."

          https://www.sciencedaily.com/releases/2021/12/211210140717.htm

 

Larger and Greener Global Rice Bowl Needed

The world can produce more rice without harming the environment, study concludes

From:  University of Nebraska-Lincoln

December 9, 2021 -- A global assessment assessed rice yields and efficiency in 32 rice cropping systems. The study concluded that there is still substantial room to increase rice production while reducing the negative environmental impacts. A leading agronomist describes the study as 'the most comprehensive global evaluation of production systems for a major staple crop, (one that) will set the standard for future global comparison.

Rice is the main food staple for more than half of the global population, and as the population grows, demand for rice is expected to grow, too.

But increasing global rice production is not a simple prospect.

"Global rice production is challenged now due to the negative environmental impact, water scarcity, labor shortage and slowing yield increases in many parts of the world," said Shen Yuan, a postdoctoral research associate at Huazhong Agricultural University in China who spent two years as a visiting scholar at the University of Nebraska-Lincoln.

The challenge is producing more rice on existing cropland, and doing so while minimizing the environmental impact. New research led by Shaobing Peng, a professor of agronomy at Huazhong Agricultural University, and Patricio Grassini, associate professor of agronomy at Nebraska and co-leader of the Global Yield Gap Atlas, provides an analysis of roadmaps toward sustainable intensification for a larger global rice bowl. The research was published Dec. 9 in Nature Communications.

"Comparing rice cropping systems around the world in terms of productivity and efficiency in the use of applied inputs can help identify opportunities for improvement," Grassini said.

The global assessment was led by Huazhong Agricultural University and the University of Nebraska-Lincoln, in collaboration with the University of California, Davis, and Texas A&M's AgriLife Research Center in the United States; the International Rice Research Institute; Africa Rice Center; Indonesian Center for Rice Research and Assessment Institute of Agricultural Technology in Indonesia; Federal University of Santa Maria and EMBRAPA Arroz e Feijão in Brazil; National Institute of Agricultural Research in Uruguay; and Indian Institute of Farming Systems Research and Indian Institute of Water Management in India. The study assessed rice yields and efficiency in the use of water, fertilizer, pesticides and labor across 32 rice cropping systems that accounted for half of global rice harvested area.

"This study is the most comprehensive global evaluation of production systems for a major staple crop that I am aware of, and it will set the standard for future global comparison of such systems," said Kenneth G. Cassman, professor emeritus at Nebraska and a co-author of the paper.

The good news, according to the study, is that there is still substantial room to increase rice production and reduce the negative environmental impact.

"Around two-thirds of the total rice area included in our study have yields that are below the yield that can be attained with good agronomic practices," Yuan said. "Closing the existing yield gap requires better nutrient, pest, soil and water management, reduction of production risk and breeding programs that release rice cultivars with improved tolerance to evolving pests and diseases."

Another important finding from the study is that food production and environmental goals do not conflict.

"We found that achieving high yields with small environmental impact per unit of production is possible," Peng said. "Indeed, there is room for many rice systems to reduce the negative impact substantially while maintaining or even increasing rice yields."

Producing more and minimizing the environmental footprint is an enormous challenge, Grassini said.

"Improved agronomic practices, complemented with proper institutions and policy, can help make rice cultivation more environmentally friendly," Grassini said. "Our study marks a first step in identifying systems with the largest opportunities for increasing crop yields and resource-use efficiency, providing a blueprint to orient agricultural research and development programs at national to global scales."

         https://www.sciencedaily.com/releases/2021/12/211209201702.htm

  

How the Body Uses Fat to Fight Infection

Peer-Reviewed Publication

From:  University of East Anglia

December 8, 2021 -- New research from the University of East Anglia and Quadram Institute reveals how our immune cells use the body’s fat stores to fight infection.

The research, published today in the journal Nature Communications, could help develop new approaches to treating people with bacterial infections.

The research team say their work could one day help treat infections in vulnerable and older people.

The team studied Salmonella - a bacterial infection which causes diarrhoea, vomiting, abdominal pain, fever and sepsis.

The UEA team collaborated with the Quadram Institute and colleagues at the Earlham Institute, to track fatty acid movement and consumption in live stem cells.

They went on to analyse the immune response to Salmonella bacterial infection, by analysing liver damage.

They uncovered how blood stem cells respond to infection, by acquiring high energy fatty acids from the body’s fat stores.

The team found that in the bone marrow where blood stem cells are resident, infection signals drive adipocytes to release their fat stores as fatty acids into the blood. 

And they identified that these high energy fatty acids are then taken up by blood stem cells, effectively feeding the stem cells and enabling them to make millions of Salmonella-fighting white blood cells.

The researchers also identified the mechanism by which the fatty acids are transferred and discusses the potential impact this new knowledge could have on future treatment of infection.

Dr Stuart Rushworth, from UEA’s Norwich Medical School, said: “Our results provide insight into how the blood and immune system is able to respond to infection.

“Fighting infection takes a lot of energy and fat stores are huge energy deposits, which provide the fuel for the blood stem cells to power up the immune response.  

“Working out the mechanism through which this ‘fuel boost’ works gives us new ideas on how to strengthen the bodies fight against infection in the future.”

Dr Naiara Beraza, from the Quadram institute, said: “Our results allow us to understand how our immune system uses fat to fuel the response to infection. Defining these mechanisms will enable us to develop new therapeutics to treat infections in the liver.”

Dr Rushworth said: “In the future, I hope our findings will help improve treatment for vulnerable and older people with infections, by strengthening their immune response.

“With antibiotic resistance being such a present and widespread challenge for society, there is an urgent need to explore novel ways like this to help the body’s immune system to fight infection,” he added.

The study was led by UEA and QI in collaboration with the Earlham Institute. It was funded by the Wellcome Trust and the Biotechnology and Biological Sciences Research Council (BBSRC), with support from the UK Medical Research Council.

‘Free fatty-acid transport via CD36 drives β-oxidation-mediated hematopoietic stem cell response to infection’ is published in the journal Nature Communications on December 8, 2021.

https://www.eurekalert.org/news-releases/937123