Fire Doesn’t Kill Some Bacteria and Fungi

Project examines microbes’ role in greenhouse gas emissions

From:  University of California Riverside

By Jules Bernstein

March 30, 2022 -- Scientists have found microbes living in the charred soil that wildfires leave behind. They don’t know how some fungi and bacteria manage to thrive when everything else has died, but a new project aims to change that. 

UC Riverside scientists will spend the next three years studying the traits that allow soil microbes to respond to fire, as well as the role those microbes play in storing or emitting powerful greenhouse gases like carbon dioxide or nitrous oxide.  

The work is funded by an $849,000 grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture. 

“There’s very little known about which microbes respond to fires, or why, or what effect they have on the rest of the environment,” said UCR mycologist Sydney Glassman. “We want to know how the fungi and bacteria that remain impact greenhouse gas emissions from post-fire soils.”

To answer their questions, Glassman and UCR environmental scientist Pete Homyak are sampling soil from two major, nearby burn scars— 2018’s Holy Fire in Orange and Riverside counties, and 2020’s El Dorado Fire, also known as the “Gender Reveal Fire” in San Bernardino County.

They’ll test whether remaining microbes have traits resembling ones found in plants that can flourish after fires. 

One such trait is the ability to reproduce quickly. “After a burn, there’s a lot of space that opens up. If they reproduce asexually, they can multiply at a particularly rapid speed and colonize that space,” Glassman said. 

A second quality is the ability to ‘feed’ on burnt things. Fire turns trees into charcoal, leaf matter into waxes, and releases large amounts of nitrogen. Most microbes don’t prefer high levels of nitrogen. However, the researchers believe it’s possible a select few do feast on a diet of charcoal or nitrogen, or wax.

Additionally, there are some plants that can simply tolerate high heat. Microbes could be the same. “There is some evidence of spores that are thermotolerant, or even require heat to reproduce,” Glassman said. 

Future projects will look not only at the characteristics of post-fire microbes, but at whether adding pre-fire fungi and bacteria back into soils could help with recovery. 

In a separate but related study, members of the group are trying to characterize the effects of flame retardants that are regularly added to vast tracts of forest land. Some of these chemicals deposit phosphorus and nitrogen that lasts for decades. The impact of that on naturally occurring microbes is also still unclear. 

“Fires have really strong impacts on soil chemistry, and the main things mediating those impacts are the microbes,” Glassman said. “The ones that survive transform the carbon and nitrogen left behind, setting the stage for regeneration. That’s why we think they’re so important to understand.”

      https://news.ucr.edu/articles/2022/03/30/why-doesnt-fire-kill-some-bacteria-and-fungi

 

Improved Eye Imaging for Robots and Cars

Using lessons learned from the eye-imaging technology optical coherence tomography (OCT), engineers have demonstrated a LiDAR system that is fast and accurate enough to potentially improve the vision of autonomous systems such as driverless cars and robotic manufacturing plants.

From:  Duke University

March 29, 2022 -- Even though robots don't have eyes with retinas, the key to helping them see and interact with the world more naturally and safely may rest in optical coherence tomography (OCT) machines commonly found in the offices of ophthalmologists.

One of the imaging technologies that many robotics companies are integrating into their sensor packages is Light Detection and Ranging, or LiDAR for short. Currently commanding great attention and investment from self-driving car developers, the approach essentially works like radar, but instead of sending out broad radio waves and looking for reflections, it uses short pulses of light from lasers.

Traditional time-of-flight LiDAR, however, has many drawbacks that make it difficult to use in many 3D vision applications. Because it requires detection of very weak reflected light signals, other LiDAR systems or even ambient sunlight can easily overwhelm the detector. It also has limited depth resolution and can take a dangerously long time to densely scan a large area such as a highway or factory floor. To tackle these challenges, researchers are turning to a form of LiDAR called frequency-modulated continuous wave (FMCW) LiDAR.

"FMCW LiDAR shares the same working principle as OCT, which the biomedical engineering field has been developing since the early 1990s," said Ruobing Qian, a PhD student working in the laboratory of Joseph Izatt, the Michael J. Fitzpatrick Distinguished Professor of Biomedical Engineering at Duke. "But 30 years ago, nobody knew autonomous cars or robots would be a thing, so the technology focused on tissue imaging. Now, to make it useful for these other emerging fields, we need to trade in its extremely high resolution capabilities for more distance and speed."

In a paper appearing March 29 in the journal Nature Communications, the Duke team demonstrates how a few tricks learned from their OCT research can improve on previous FMCW LiDAR data-throughput by 25 times while still achieving submillimeter depth accuracy.

OCT is the optical analogue of ultrasound, which works by sending sound waves into objects and measuring how long they take to come back. To time the light waves' return times, OCT devices measure how much their phase has shifted compared to identical light waves that have travelled the same distance but have not interacted with another object.

FMCW LiDAR takes a similar approach with a few tweaks. The technology sends out a laser beam that continually shifts between different frequencies. When the detector gathers light to measure its reflection time, it can distinguish between the specific frequency pattern and any other light source, allowing it to work in all kinds of lighting conditions with very high speed. It then measures any phase shift against unimpeded beams, which is a much more accurate way to determine distance than current LiDAR systems.

"It has been very exciting to see how the biological cell-scale imaging technology we have been working on for decades is directly translatable for large-scale, real-time 3D vision," Izatt said. "These are exactly the capabilities needed for robots to see and interact with humans safely or even to replace avatars with live 3D video in augmented reality."

Most previous work using LiDAR has relied on rotating mirrors to scan the laser over the landscape. While this approach works well, it is fundamentally limited by the speed of the mechanical mirror, no matter how powerful the laser it's using.

The Duke researchers instead use a diffraction grating that works like a prism, breaking the laser into a rainbow of frequencies that spread out as they travel away from the source. Because the original laser is still quickly sweeping through a range of frequencies, this translates into sweeping the LiDAR beam much faster than a mechanical mirror can rotate. This allows the system to quickly cover a wide area without losing much depth or location accuracy.

While OCT devices are used to profile microscopic structures up to several millimeters deep within an object, robotic 3D vision systems only need to locate the surfaces of human-scale objects. To accomplish this, the researchers narrowed the range of frequencies used by OCT, and only looked for the peak signal generated from the surfaces of objects. This costs the system a little bit of resolution, but with much greater imaging range and speed than traditional LiDAR.

The result is an FMCW LiDAR system that achieves submillimeter localization accuracy with data-throughput 25 times greater than previous demonstrations. The results show that the approach is fast and accurate enough to capture the details of moving human body parts -- such as a nodding head or a clenching hand -- in real-time.

"In much the same way that electronic cameras have become ubiquitous, our vision is to develop a new generation of LiDAR-based 3D cameras which are fast and capable enough to enable integration of 3D vision into all sorts of products," Izatt said. "The world around us is 3D, so if we want robots and other automated systems to interact with us naturally and safely, they need to be able to see us as well as we can see them."

This research was supported by the National Institutes of Health (EY028079), the National Science Foundation, (CBET-1902904) and the Department of Defense CDMRP (W81XWH-16-1-0498).

Story Source:

Materials provided by Duke University. Original written by Ken Kingery. Note: Content may be edited for style and length.

https://www.sciencedaily.com/releases/2022/03/220329114712.htm                                                        

 

Record Efficiency for Ultra-thin Solar Panels

A team co-led by the University of Surrey has successfully increased the levels of energy absorbed by wafer-thin photovoltaic panels by 25%.

From:  The University of Surrey

March 29, 2022 -- Their solar panels, just one micrometre thick (1μm), convert light into electricity more efficiently than others as thin and pave the way to make it easier to generate more clean, green energy. 

In a paper published in the American Chemical Society’s Photonics journal, the team detail how they used characteristics of sunlight to design a disordered honeycomb layer which lies on top of a wafer of silicon. Their approach is echoed in nature in the design of butterfly wings and bird eyes. The innovative honeycomb design enables light absorption from any angle and traps light inside the solar cell, enabling more energy to be generated. 

Dr Marian Florescu from the University of Surrey’s Advanced Technology Institute (ATI) said, “One of the challenges of working with silicon is that nearly a third of light bounces straight off it without being absorbed and the energy harnessed. A textured layer across the silicon helps tackle this and our disordered, yet hyper-uniform, honeycomb design is particularly successful.”

The team of researchers from the University of Surrey and Imperial College London worked with experimental collaborators at AMOLF in Amsterdam to design, model and create the new ultra-thin photovoltaic. 

In the laboratory, they achieved absorption rates of 26.3 mA/cm2, a 25% increase on the previous record of 19.72 mA/cm2 achieved in 2017. They secured an efficiency of 21% but anticipate that further improvements will push the figure higher, resulting in efficiencies that are significantly better than many commercially available photovoltaics. 

Dr Florescu continued, “There’s enormous potential for using ultra-thin photovoltaics. For example, given how light they are, they will be particularly useful in space and could make new extra-terrestrial projects viable. Since they use so much less silicon, we are hoping there will be cost savings here on Earth as well, plus there could be potential to bring more benefits from the Internet of Things and to create zero-energy buildings powered locally.” 

As well as benefiting solar power generation, the findings could also benefit other industries where light management and surface engineering are crucial, for example, photo-electrochemistry, solid-state light emission and photodetectors. 

Next steps for the team will include investigating commercial partners and developing manufacturing techniques. 

https://www.surrey.ac.uk/news/scientists-achieve-record-efficiency-ultra-thin-solar-panels

 

Unravelling the mystery of parrot longevity

Bigger brains have led some species of parrot to live surprisingly long lives, new research shows

From:  Max-Planck-Gesellschaft

March 29, 2022

Parrots are famous for their remarkable cognitive abilities and exceptionally long lifespans. Now, a study led by Max Planck researchers has shown that one of these traits has likely been caused by the other. By examining 217 parrot species, the researchers revealed that species such as the scarlet macaw and sulphur-crested cockatoo have extremely long average lifespans, of up to 30 years, which are usually seen only in large birds. Further, they demonstrated a possible cause for these long lifespans: large relative brain size. The study is the first to show a link between brain size and lifespan in parrots, suggesting that increased cognitive ability may have helped parrots to navigate threats in their environment and to enjoy longer lives.

Despite the fact that parrots are well known for their long lives and complex cognition, with lifespans and relative brain size on par with primates, it remains unknown whether the two traits have influenced each other.

"The problem has been sourcing good quality data," says Simeon Smeele, a doctoral student at the Max Planck Institute of Animal Behavior (MPI-AB) and lead author on the study, published in Proceedings of the Royal Society B. Understanding what has driven parrot longevity is only possible by comparing living parrots. "Comparative life-history studies require large sample sizes to provide certainty, because many processes are a play at once and this creates a lot of variation," says Smeele.

To generate an adequate sample size, scientists from the MPI-AB and the Max Planck Institute for Evolutionary Anthropology (MPI-EvA) teamed up with Species360, which draws on animal records from zoos and aquaria. Together, they compiled data from over 130,000 individual parrots sourced from over 1000 zoos. This database allowed the team to gain the first reliable estimates of average life span of 217 parrot species -- representing over half of all known species.

The analysis revealed an astonishing diversity in life expectancy, ranging from an average of two years for the fig parrot up to an average of 30 years for the scarlet macaw. Other long-lived species include the sulphur crested cockatoo from Australia, which lives on average 25 years.

"Living an average of 30 years is extremely rare in birds of this size," says Smeele who worked closely with Lucy Aplin from MPI-AB and Mary Brooke McElreath from MPI-EvA on the study. "Some individuals have a maximum lifespan of over 80 years, which is a respectable age even for humans. These values are really spectacular if you consider that a human male weights about 100 times more."

Next, the team employed a large-scale comparative analysis to determine whether or not parrots' renowned cognitive abilities had any influence on their longevity. They examined two hypotheses: First, that having relatively larger brains enable longer lifespans. In other words, smarter birds can better solve problems in the wild, thus enjoying longer lives. Second, that relatively larger brains take longer to grow, and therefore require longer lifespans. For each species, they collected data on relative brain size, as well as average body weight and developmental variables.

They then combined the data and ran models for each hypothesis, looking at which model best explained the data. Their results provide the first support that increased brain size has enabled longer lifespans in parrots. Because brain size relative to body size can be an indicator for intelligence, the findings suggest that the parrots with relatively large brains had cognitive capabilities that allowed them to solve problems in the wild that could otherwise kill them, and this intelligence enabled them to live longer lives.

"This supports the idea that in general larger brains make species more flexible and allow them to live longer," says Smeele. "For example, if they run out of their favourite food, they could learn to find something new and thus survive."

The scientists are surprised that factors such as diet, or the greater developmental time required to develop larger brains, did not lead to longer average lifespans. "We would have expected the developmental path to play a more important role because in primates it is this developmental cost that explains the link between brain size and longevity," says Smeele.

In the future, the team plan to explore if sociality and cultural learning in parrots might have also contributed to long lifespans. Says Smeele: "Large-brained birds might spend more time socially learning foraging techniques that have been around for multiple generations. This increased learning period could potentially also explain the longer life spans, as it takes more time but also makes the foraging repertoire more adaptive."

"One thing that makes us humans special is the vast body of socially learned skills. We are really excited to see if long-lived parrots also have a 'childhood' in which they have to learn everything from finding and opening nuts to avoid upsetting the dominant male. Ultimately, we would like to understand which evolutionary drivers create a species with a life-history very similar to our ancestors."

              https://www.sciencedaily.com/releases/2022/03/220329152826.htm

 

Very Creative People Think Differently

Layover or nonstop? UCLA Health research says unique pattern of connectivity lets highly creative people’s brains take road less traveled to their destination

From:  UCLA Health

March 28, 2022 -- A new study led by UCLA Health scientists shows highly creative people’s brains appear to work differently from others', with an atypical approach that makes distant connections more quickly by bypassing the “hubs” seen in non-creative brains.

Exceptionally creative visual artists and scientists – called “Big C” creative types – volunteered to undergo functional MRI brain imaging, giving researchers in psychiatry, behavioral sciences and psychology a look at how regions of the brain connected and interacted when called upon to perform tasks that put creative thinking to the test.

“Our results showed that highly creative people had unique brain connectivity that tended to stay off the beaten path,” said Ariana Anderson, a professor and statistician at the Semel Institute for Neuroscience and Human Behavior at UCLA, the lead author of a new article in the journal Psychology of Aesthetics, Creativity, and the Arts. While non-creatives tended to follow the same routes across the brain, the highly creative people made their own roads.

Although the concept of creativity has been studied for decades, little is known about its biological bases, and even less is understood about the brain mechanisms of exceptionally creative people, said senior author Robert Bilder, director of the Tennenbaum Center for the Biology of Creativity at the Semel Institute. This uniquely designed study included highly creative people representing two different domains of creativity – visual arts and the sciences – and used an IQ-matched comparison group to identify markers of creativity, not just intelligence. The researchers analyzed how connections were made between brain regions globally and locally.

“Exceptional creativity was associated with more random connectivity at the global scale – a pattern that is less ‘efficient’ but would appear helpful in linking distant brain nodes to each other,” Bilder said. “The patterns in more local brain regions varied, depending on whether people were performing tasks. Surprisingly, Big C creatives had more efficient local processing at rest, but less efficient local connectivity when performing a task demanding ‘thinking outside the box.’”

Using airline route maps for comparison, the researchers said the Big C creatives’ brain activity is akin to skipping flights to connecting hubs to get to a small city.

“In terms of brain connectivity, while everyone else is stuck in a three-hour layover at a major airport, the highly creatives take private planes directly to a distant destination,” Anderson said. “This more random connectivity may be less efficient much of the time, but the architecture enables brain activity to ‘take a road less traveled’ and make novel connections.”

Bilder, who has more than 30 years’ experience researching brain-behavior relations, said, “The fact that Big C people had more efficient local brain connectivity, but only under certain conditions, may relate to their expertise. Consistent with some of our prior findings, they may not need to work as hard as other smart people to perform certain creative tasks.”

The artists and scientists in the study were nominated by panels of experts before being validated as exceptional based on objective metrics. The “smart” comparison group was recruited from participants in a previous UCLA study who had agreed to be contacted for possible participation in future studies, and from advertisements in the community for individuals with graduate degrees. The researchers made efforts to ensure that age, sex, race and ethnicity were comparable to those of participants in the Big C groups.

In addition to Bilder and Anderson, authors include Kevin Japardi, a data intelligence analyst at Cedars-Sinai Medical Center; Kendra Knudsen, a researcher in psychology at UCLA; Susan Bookheimer, a researcher in psychiatry, behavioral sciences and psychology at UCLA; and Dara Ghahremani, a researcher in psychiatry and behavioral sciences at UCLA.

The authors report no additional disclosures or potential conflicts of interest.

               https://www.uclahealth.org/news/CreativeBrain2022

 

Speed Limit of Computers Detected

One million gigahertz: This is the physical limit of the signal speed in transistors, as a German-Austrian physics team has now discovered.

From:  Graz University of Technology, Graz, Austria

By Christoph Pelzl

March 25, 2022 -- An international research group has found out how fast a computer can become maximum.  The maximum speed of signal transmission in microchips is about one petahertz (one million gigahertz), which is about 100,000 times faster than current transistors. Physicists from Ludwig Maximilian University of Munich, the Max Planck Institute of Quantum Optics and Vienna and Graz Universities of Technology have recently published this finding in the scientific journal Nature Communications. Whether computer chips of this maximum speed can ever actually be produced is, however, questionable.

Microelectronics is pursuing two approaches to making computers faster. On the one hand, work is being done to make the components ever smaller so that data transmission (signal path from A to B) literally “doesn’t take so long”. The physical limit of this miniaturization is the size of an atom. A circuit cannot be physically smaller.

The second possibility for faster data transmission is to speed up the switching signals of the transistors themselves. These are the components in microchips that either block or allow current to flow. And this is where the research of the German-Austrian physics group came in.

High-frequency light as a speed booster

Fast in this case means “high-frequency”, as Martin Schultze, the lead author and head of the Institute of Experimental Physics at Graz University of Technology (TU Graz), explains: “The faster you want to go, the more high frequency the electromagnetic signal has to be – and at some point we come into the range of the frequency of light, which can also be considered or used as an electromagnetic signal.” This happens, for example, in optoelectronics, where light is used to excite the electrons in the semiconductor from the valence band (the area where the electrons normally reside) to the conduction band, so that it changes from the isolated to the conductive state. The excitation energy is determined by the semiconductor material itself. It lies in the frequency range of infra-red light, which ultimately also corresponds to the maximum achievable speed that can be reached with such materials.

Dielectric material: first-class candidate for speed records

Dielectric materials (such as glass or ceramics) could overcome these limitations, as they require much more energy to be excited compared to semiconductors. More energy in turn allows the use of higher-frequency light and thus faster data transmission. Unfortunately, however, dielectric materials cannot conduct electricity without breaking, as Marcus Ossiander, first author of the study and currently a post-doctoral researcher at Harvard University, illustrates: “For example, if you apply an electromagnetic field to glass so that it conducts electricity, this usually results in the glass breaking and leaving a hole.”
The solution that the research group chose for their investigations was to keep the applied voltage pulse or the switching frequency so short that the material has no time to break at all.

The right pulse provides the right answers

Specifically, the physicists used an ultra-short laser pulse with a frequency in the extreme UV range for their investigations. They bombarded a lithium fluoride sample with this laser pulse. Lithium fluoride is dielectric and has the largest band gap of all known materials. This is the distance between the valence band and the conduction band.

The ultra-short laser pulse brought the electrons in the lithium fluoride into a more energetic state so that they could move freely. In this way, the material briefly became an electrical conductor. A second, slightly longer laser pulse steered the excited electrons in a desired direction, creating an electric current that could then be detected with electrodes on both sides of the material. The measurements provided answers to the questions of how quickly the material reacted to the ultra-short laser pulse, how long the signal generation took, and how long one has to wait until the material can be exposed to the next signal. “It follows that at about one petahertz there is an upper limit for controlled optoelectronic processes,” says Joachim Burgförder from the Institute for Theoretical Physics at TU Wien.

This, of course, does not mean that computer chips can be produced with a clock frequency of just under one petahertz. But one thing is certain: for now, optoelectronics will not become faster than was shown in the experiments. How close future technologies will come to this limit is written in the stars.

Martin Schultze’s research is anchored in the Field of Expertise "Advanced Materials Science" one of five strategic focus areas of TU Graz.

https://www.tugraz.at/en/tu-graz/services/news-stories/planet-research/singleview/article/speedlimit-fuer-computer-ermittelt0/

  

New Battery for Transportation and Grid Use

Researchers uncover new avenue for overcoming the performance decline that occurs with repeated charge-discharge cycling in the cathodes of next generation batteries.

From:  U.S. Department of Energy’s (DOE) Argonne National Laboratory

By Joseph E. Harmon

March 23, 2022 -- Battery-powered vehicles have made a significant dent in the transportation market. But that market still needs lower cost batteries that can power vehicles for greater ranges. Also desirable are low-cost batteries able to store on the grid the intermittent clean energy from solar and wind technologies and power hundreds of thousands of homes.

To meet those needs, researchers around the world are racing to develop batteries beyond the current standard of lithium-ion materials. One of the more promising candidates is the sodium-ion battery. It is particularly attractive because of the greater abundance and lower cost of sodium compared with lithium. What’s more, when cycled at high voltage (4.5 volts), a sodium-ion battery can greatly increase the amount of energy that can be stored in a given weight or volume. However, its fairly rapid performance decline with charge-discharge cycling has stymied commercialization.

Researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory have discovered a key reason for the performance degradation: the occurrence of defects in the atomic structure that form during the steps involved in preparing the cathode material. These defects eventually lead to a structural earthquake in the cathode, resulting in catastrophic performance decline during battery cycling. Armed with this knowledge, battery developers will now be able to adjust synthesis conditions to fabricate far superior sodium-ion cathodes.

Key to making this discovery was the team’s reliance on the world-class scientific capabilities available at Argonne’s Center for Nanoscale Materials (CNM) and Advanced Photon Source (APS), both of which are DOE Office of Science user facilities.

“These capabilities allowed us to track changes in the atomic structure of the cathode material in real time while it is being synthesized,” said Guiliang Xu, assistant chemist in Argonne’s Chemical Sciences and Engineering division.

During cathode synthesis, material fabricators slowly heat the cathode mixture to a very high temperature in air, hold it there for a set amount of time, then rapidly drop the temperature to room temperature.

“Seeing is believing,” said Yuzi Liu, a CNM nanoscientist. ​“With Argonne’s world-class scientific facilities, we do not have to guess what is happening during the synthesis.” To that end, the team called upon the transmission electron microscope in CNM and synchrotron X-ray beams at the APS (at beamlines 11-ID-C and 20-BM).

Their data revealed that, upon rapidly dropping the temperature during material synthesis, the cathode particle surface had become less smooth and exhibited large areas indicating strain. The data also showed that a push-pull effect in these areas happens during cathode cycling, causing cracking of the cathode particles and performance decline.

Upon further study, the team found that this degradation intensified when cycling cathodes at high temperature (130 degrees Fahrenheit) or with fast charging (one hour instead of 10 hours).

“Our insights are extremely important for the large-scale manufacturing of improved sodium-ion cathodes,” noted Khalil Amine, an Argonne Distinguished Fellow. ​“Because of the large amount of material involved, say, 1000 kilograms, there will be a large temperature variation, which will lead to many defects forming unless appropriate steps are taken.”

Earlier research by team members had resulted in a greatly improved anode.  “Now, we should be able to match our improved cathode with the anode to attain a 20% - 40% increase in performance,” said Xu. ​“Also important, such batteries will maintain that performance with long-term cycling at high voltage.”

The impact could result in a longer driving range in more affordable electric vehicles and lower cost for energy storage on the electric grid.

The team published their research in Nature Communications in an article entitled, “Native lattice strain induced structural earthquake in sodium layered oxide cathodes.” In addition to Xu, Liu and Amine, authors include Xiang Liu, Xinwei Zhou, Chen Zhao, Inhui Hwang, Amine Daali, Zhenzhen Yang, Yang Ren, Cheng-Jun Sun and Zonghai Chen. Zhou and Liu performed the analyses at CNM while Ren and Sun did the analyses at APS.

This research was supported by DOE’s Vehicle Technologies Office.

Pivotal battery discovery could impact transportation and the grid | Argonne National Laboratory (anl.gov)

 

Why the Vikings Left Greenland

It was probably drought rather than the Little Ice Age

From:  The University of Massachusetts Amherst

March 23, 2022 -- One of the great mysteries of late medieval history is why did the Norse, who had established successful settlements in southern Greenland in 985, abandon them in the early 15th century?

The consensus view has long been that colder temperatures, associated with the Little Ice Age, helped make the colonies unsustainable. However, new research, led by the University of Massachusetts Amherst and published recently in Science Advances, upends that old theory. It wasn’t dropping temperatures that helped drive the Norse from Greenland, but drought.

When the Norse settled in Greenland on what they called the Eastern Settlement in 985, they thrived by clearing the land of shrubs and planting grass as pasture for their livestock. The population of the Eastern Settlement peaked at around 2,000 inhabitants, but collapsed fairly quickly about 400 years later.

For decades, anthropologists, historians and scientists have thought the Eastern Settlement’s demise was due to the onset of the Little Ice Age, a period of exceptionally cold weather, particularly in the North Atlantic, that made agricultural life in Greenland untenable.

However, as Raymond Bradley, University Distinguished Professor of geosciences at UMass Amherst and one of the paper’s co- author, points out,

“Before this study, there was no data from the actual site of the Viking settlements. And that’s a problem.”

Instead, the ice core data that previous studies had used to reconstruct historical temperatures in Greenland was taken from a location that was over 1,000 kilometers to the north and over 2,000 meters higher in elevation. “We wanted to study how climate had varied close to the Norse farms themselves,” says Bradley. And when they did, the results were surprising.

Bradley and his colleagues traveled to a lake called Lake 578, which is adjacent to a former Norse farm and close to one of the largest groups of farms in the Eastern Settlement. There, they spent three years gathering sediment samples from the lake, which represented a continuous record for the past 2,000 years.

“Nobody has actually studied this location before,” says Boyang Zhao, the study’s lead author who conducted this research for his Ph.D. in geosciences at UMass Amherst and is currently a postdoctoral research associate at Brown University.”  -- says Zhao

They then analyzed that 2,000 year sample for two different markers: the first, a lipid, known as BrGDGT, can be used to reconstruct temperature. “If you have a complete enough record, you can directly link the changing structures of the lipids to changing temperature,” says Isla Castañeda, professor of geosciences at UMass Amherst and one of the paper’s co-authors.

A second marker, derived from the waxy coating on plant leaves, can be used to determine the rates at which the grasses and other livestock-sustaining plants lost water due to evaporation. It is therefore an indicator of how dry conditions were.

“What we discovered is that, while the temperature barely changed over the course of the Norse settlement of southern Greenland, it became steadily drier over time.”  says Zhao

Norse farmers had to overwinter their livestock on stored fodder, and even in a good year the animals were often so weak that they had to be carried to the fields once the snow finally melted in the spring. Under conditions like that, the consequences of drought would have been severe. An extended drought, on top of other economic and social pressures, may have tipped the balance just enough to make the Eastern Settlement unsustainable.

Scientists at Smith College and the University at Buffalo also contributed to the research, which was supported by the National Science Foundation, UMass Amherst, the Geological Society of America, and the Swiss National Science Foundation, changes our understanding of early European history, and highlights the importance of continuing to explore how environmental factors influence human society. The new findings change our understanding of early European history and highlight the importance of continuing to explore how environmental factors influence human society.

    https://www.umass.edu/news/article/rewriting-history-books-why-vikings-left-greenland

 

Our Sun Didn’t Have Sunspots for 70 Years

Nearby star also lacks sunspots and might help explain why

From:  Penn State University

By Gail McCormick

March 22, 2022 -- The number of sunspots on our Sun typically ebbs and flows in a predictable 11-year cycle, but one unusual 70-year period when sunspots were incredibly rare has mystified scientists for 300 years. Now a nearby Sun-like star seems to have paused its own cycles and entered a similar period of rare starspots, according to a team of researchers at Penn State. Continuing to observe this star could help explain what happened to our own Sun during this “Maunder Minimum” as well as lend insight into the Sun's stellar magnetic activity, which can interfere with satellites and global communications and possibly even affect climate on Earth.
 
The star—and a catalog of 5 decades of starspot activity of 58 other Sun-like stars—is described in a new paper that appears online in the Astronomical Journal.

Starspots appear as a dark spot on a star’s surface due to temporary lower temperatures in the area resulting from the star’s dynamo—the process that creates its magnetic field. Astronomers have been documenting changes in starspot frequency on our Sun since they were first observed by Galileo and other astronomers in the 1600s, so there is a good record of its 11-year cycle. The exception is the Maunder Minimum, which lasted from the mid 1600s to early 1700s and has perplexed astronomers ever since.
 
“We don’t really know what caused the Maunder Minimum, and we have been looking to other Sun-like stars to see if they can offer some insight,” said Anna Baum, an undergraduate at Penn State at the time of the research and first author of the paper. “We have identified a star that we believe has entered a state similar to the Maunder Minimum. It will be really exciting to continue to observe this star during, and hopefully as it comes out of, this minimum, which could be extremely informative about the Sun’s activity 300 years ago.”
 
The research team pulled data from multiple sources to stitch together 50 to 60 years of starspot data for 59 stars. This included data from the Mount Wilson Observatory HK Project—which was designed to study stellar surface activity and ran from 1966 to 1996—and from planet searches at Keck Observatory which include this kind of data as part of their ongoing search for exoplanets from 1996 to 2020. The researchers compiled a database of stars that appeared in both sources and that had other readily available information that might help explain starspot activity. The team also made considerable efforts to standardize measurements from the different telescopes to be able to compare them directly and otherwise clean up the data.
 
The team identified or confirmed that 29 of these stars have starspot cycles by observing at least two full periods of cycles, which often last more than a decade. Some stars did not appear to have cycles at all, which could be because they are rotating too slowly to have a dynamo and are magnetically ‘dead’ or because they are near the end of their lives. Several of the stars require further study to confirm whether they have a cycle.
 
“This continuous, more than 50-year time series allows us to see things that we never would have noticed from the 10-year snapshots that we were doing before,” said Jason Wright, professor of astronomy and astrophysics at Penn State and an author of the paper. “Excitingly, Anna has found a promising star that was cycling for decades but appears to have stopped.”
 
According to the researchers, the star—called HD 166620—was estimated to have a cycle of about 17 years but has now entered a period of low activity and has shown no signs of starspots since 2003.
 
“When we first saw this data, we thought it must have been a mistake, that we pulled together data from two different stars or there was a typo in the catalog or the star was misidentified,” said Jacob Luhn, a graduate student at Penn State when the project began who is now at the University of California, Irvine. “But we double- and triple-checked everything. The times of observation were consistent with the coordinates we expected the star to have. And there aren’t that many bright stars in the sky that Mount Wilson observed. No matter how many times we checked, we always come to the conclusion that this star has simply stopped cycling.”
 
The researchers hope to continue studying this star throughout its minimum period and potentially as it comes out of its minimum and begins to cycle once again. This continued observation could provide important information about how the Sun and stars like it generate their magnetic dynamos.
 
“There’s a big debate about what the Maunder Minimum was,” said Baum, who is now a doctoral student at Lehigh University studying stellar astronomy and asteroseismology . “Did the Sun’s magnetic field basically turn off? Did it lose its dynamo? Or was it still cycling but at a very low level that didn’t produce many sunspots? We can’t go back in time to take measurements of what it was like, but if we can characterize the magnetic structure and magnetic field strength of this star, we might start to get some answers.”

A better understanding of the surface activity and magnetic field of the Sun could have several important implications. For example, strong stellar activity can disable satellites and global communications, and one particularly strong solar storm disabled a power grid in Quebec in 1989. It has also been suggested that sunspot cycles may have a connection to climate on Earth. Additionally, the researchers said that information from this star could impact our search for planets beyond our solar system.
 
“Starspots and other forms of surface magnetic activity of stars interfere with our ability to detect the planets around them,” said Howard Isaacson, a research scientist at the University of California, Berkeley, and an author of the paper. “Improving our understanding of a star’s magnetic activity might help us improve our detection efforts.”
 
The curated database of the 59 stars and their starspot activity from this research has been made available for researchers to further investigate
 
“This research is a great example of cross-generational astronomy, and how we continue to improve our understanding of the universe by building upon the many observations and dedicated research of astronomers that came before us,” said Wright. “I looked at starspot data from Mount Wilson and Keck Observatory for my thesis when I was a graduate student, Howard looked at starspot data from the California Planet Survey for his master’s thesis, and now Anna has stitched together all the data for a more comprehensive look across the years. We are all excited to continue studying this and other promising stars.”

                               https://science.psu.edu/news/Wright3-2022

  

World Water Day

Not to be confused with World Water Monitoring Day.

World Water Day is an annual United Nations (UN) observance day held on 22 March that highlights the importance of fresh water.  The day is used to advocate for the sustainable management of freshwater resources.  The theme of each day focuses on topics relevant to clean water, sanitation and hygiene (WASH), which is in line with the targets of Sustainable Development Goal 6.  The UN World Water Development Report (WWDR) is released each year around World Water Day.

UN-Water is the convener for World Water Day and selects the theme for each year in consultation with UN organizations that share an interest in that year's focus.  The theme for 2021 was "Valuing Water" and the public campaign invited people to join a global conversation on social media to "tell us your stories, thoughts and feelings about water".

In 2020, the theme was "Water and Climate Change".  Previous themes for the years 2016 to 2019 were "Water and Jobs'", "Why waste water?" "Nature for Water", and "Leaving no one behind".  World Water Day is celebrated around the world with a variety of events. These can be theatrical, musical or lobbying in nature. The day can also include campaigns to raise money for water projects. The first World Water Day, designated by the United Nations, was in 1993.

Objectives and structure

World Water Day is an international observance day. The intention is to inspire people around the world to learn more about water-related issues and to take action to make a difference.  In 2020, due to the COVID-19 pandemic, there was an additional focus on hand washing and hygiene.

Relevant issues include water scarcity, water pollution, inadequate water supply, lack of sanitation, and the impacts of climate change (which is the theme of World Water Day 2020). The day brings to light the inequality of access to WASH services and the need to assure the human right to water and sanitation.

The World Water Day website announces events, activities and volunteer opportunities. In 2020, featured stories are about adapting to the water effects climate change and using water more efficiently.

Convener

UN-Water coordinates activities with UN member organisations who share an interest in that year's theme.  UN-Water mobilizes organizations of all kinds to action, whether globally or locally.

Examples of activities

Non-governmental organizations active in the WASH sector, such as UNICEF, WaterAid and Water and Sanitation for the Urban Poor (WSUP), use the day to raise public awareness, get media attention for water issues and inspire action.  Activities have included releasing publications and films, as well as organizing round tables, seminars and expositions.

End Water Poverty, a global civil society coalition with 250 partner organizations, sponsors Water Action Month each year and offers an event-planning guidebook.

The UN World Water Development Report (WWDR) is released each year on World Water Day. Information related to the annual theme gives decision-makers tools to implement sustainable use of water resources.

More and more initiatives in schools and universities are educating people about the importance of conserving and managing water resources.  For example, Michigan State University held a contest for "best World Water Day poster" in 2017. Primary school children in the Philippines participated in a "My School Toilet" contest in 2010.

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

 

World Happiness Report for 2022

The pandemic brought an increase in social support and benevolence

From: McGill University [in Canada]

March 18, 2022 -- In this troubled time of war and pandemic, the World Happiness Report 2022 shows a bright light in dark times. According to the team of international researchers, including McGill University Professor Christopher Barrington-Leigh, the pandemic brought not only pain and suffering but also an increase in social support and benevolence.

As the world battles the ills of disease and war, it is especially important to remember the universal desire for happiness and the capacity of individuals to rally to each other’s support in times of great need, say the authors of the report. This year marks the 10^th anniversary of the World Happiness Report, which uses global survey data to report on how people evaluate their own lives in more than 150 countries around the world reaching over 9 million people in 2021.

“COVID-19 is the biggest health crisis we’ve seen in more than a century,” says Professor John Helliwell of the University of British Columbia. “Now that we have two years of evidence, we are able to assess not just the importance of benevolence and trust, but to see how they have contributed to well-being during the pandemic.”

Growth in acts of kindness

Helliwell adds “We found during 2021 remarkable worldwide growth in all three acts of kindness monitored in the Gallup World Poll. Helping strangers, volunteering, and donations in 2021 were strongly up in every part of the world, reaching levels almost 25% above their pre-pandemic prevalence. This surge of benevolence, which was especially great for the helping of strangers, provides powerful evidence that people respond to help others in need, creating in the process more happiness for the beneficiaries, good examples for others to follow, and better lives for themselves.”

Finland takes the top spot while Canada drops to 15^th place

For the fifth year in a row Finland takes the top spot as the happiest in the world. This year its score was significantly ahead of other countries in the top ten. Denmark continues to occupy second place, with Iceland up from 4^th place last year to 3^rd this year. Switzerland is 4^th, followed by the Netherlands and Luxembourg. The top ten are rounded out by Sweden, Norway, Israel and New Zealand. The next five are Austria, Australia, Ireland, Germany and Canada, in that order. This marks a substantial fall for Canada, which was 5^th ten years ago.

“The downward trend for Canada is significant and has been going on steadily for years. While Canada once ranked beside the Scandinavian countries, it now ranks closer to the United States in people's overall evaluation of how good their lives felt,” says Professor Christopher Barrington-Leigh of McGill University.

The rest of the top 20 include the United States at 16^th (up from 19^th last year), the UK and the Czechia still in 17^th and 18^th, followed by Belgium at 19^th and France at 20^th, its highest ranking yet. Overall, the three biggest gains were in Serbia, Bulgaria, and Romania. The biggest losses were in Lebanon, Venezuela, and Afghanistan.

1. Finland
2. Denmark
3. Iceland
4. Switzerland
5. Netherlands
6. Luxembourg
7. Sweden
8. Norway
9. Israel
10. New Zealand
11. Austria
12. Australia
13. Ireland
14. Germany
15. Canada

Conflict in Afghanistan takes a toll

Jan-Emmanuel De Neve, the Director of the Wellbeing Research Centre at the University of Oxford notes that “At the very bottom of the ranking we find societies that suffer from conflict and extreme poverty, notably we find that people in Afghanistan evaluate the quality of their own lives as merely 2.4 out of 10. This presents a stark reminder of the material and immaterial damage that war does to its many victims and the fundamental importance of peace and stability for human wellbeing.”

Progress marked by measures of happiness

“The World Happiness Report is changing the conversation about progress and wellbeing. It provides important snapshots of how people around the world feel about the overall quality of their lives,” says McGill University Professor Christopher Barrington-Leigh. According to the researchers, this information can in turn help countries to craft policies aimed at achieving happier societies.

Past reports have looked at the links between people’s trust in government and institutions with happiness. The findings demonstrate that communities with high levels of trust are happier and more resilient in the face of a wide range of crises.

https://www.mcgill.ca/newsroom/channels/news/amid-war-and-disease-world-happiness-report-shows-bright-spot-338506

 

New Form of Ice Discovered

Findings could have implications for our understanding of distant, water-rich planets

From:  University of Nevada – Las Vegas

March 18, 2022 -- UNLV researchers have discovered a new form of ice, redefining the properties of water at high pressures.

Solid water, or ice, is like many other materials in that it can form different solid materials based on variable temperature and pressure conditions, like carbon forming diamond or graphite. However, water is exceptional in this aspect as there are at least 20 solid forms of ice known to us.

A team of scientists working in UNLV's Nevada Extreme Conditions Lab pioneered a new method for measuring the properties of water under high pressure. The water sample was first squeezed between the tips of two opposite-facing diamonds -- freezing into several jumbled ice crystals. The ice was then subjected to a laser-heating technique that temporarily melted it before it quickly re-formed into a powder-like collection of tiny crystals.

By incrementally raising the pressure, and periodically blasting it with the laser beam, the team observed the water ice make the transition from a known cubic phase, Ice-VII, to the newly discovered intermediate, and tetragonal, phase, Ice-VIIt, before settling into another known phase, Ice-X.

Zach Grande, a UNLV Ph.D. student, led the work which also demonstrated that the transition to Ice-X, when water stiffens aggressively, occurs at much lower pressures than previously thought.

While it's unlikely we'll find this new phase of ice anywhere on the surface of Earth, it is likely a common ingredient within the mantle of Earth as well as in large moons and water-rich planets outside of our solar system.

The team's findings were reported in the March 17 issue of the journal Physical Review B.

Takeaways

The research team had been working to understand the behavior of high-pressure water that may be present in the interior of distant planets.

To do so, Grande and UNLV physicist Ashkan Salamat placed a sample of water between the tips of two round-cut diamonds known as diamond anvil cells, a standard feature in the field of high pressure physics. Applying a little bit of force to the diamonds enabled the researchers to recreate pressures as high as those found at the center of the Earth.

By squeezing the water sample between these diamonds, scientists drove the oxygen and hydrogen atoms into a variety of different arrangements, including the newly discovered arrangement, Ice-VIIt.

Not only did the first-of-its-kind laser-heating technique allow scientists to observe a new phase of water ice, but the team also found that the transition to Ice-X occurred at pressures nearly three times lower than previously thought -- at 300,000 atmospheres instead of 1 million. This transition has been a highly debated topic in the community for several decades.

"Zach's work has demonstrated that this transformation to an ionic state occurs at much, much lower pressures than ever thought before," Salamat said. "It's the missing piece, and the most precise measurements ever on water at these conditions."

The work also recalibrates our understanding of the composition of exoplanets, Salamat added. Researchers hypothesize that the Ice-VIIt phase of ice could exist in abundance in the crust and upper mantle of expected water-rich planets outside of our solar system, meaning they could have conditions habitable for life.

            https://www.sciencedaily.com/releases/2022/03/220318170514.htm

 

New Favorite Activity of America’s Youth

Birding, of all things, has enjoyed an ascendant rise in popularity since the start of the pandemic

Tanner Garrity has written an article for Inside Hook to explain why bird watching has become popular recently.  His March 18 piece is available at this link:

https://www.insidehook.com/article/health-and-fitness/birding-popular-social-media