Hexbyte Glen Cove Bioengineer aims to turn nature's virus fighters into powerful drugs thumbnail

Hexbyte Glen Cove Bioengineer aims to turn nature’s virus fighters into powerful drugs

Hexbyte Glen Cove

Credit: CC0 Public Domain

Among the powerful biochemicals of the human immune system, peptides are one of the best.

Most commonly found in the places where microbes love to take root—mucous membranes of the eye, mouth, nose and lungs—they’re known to kill all sorts of tiny invaders, such as viruses, bacteria and fungi.

Given their power, one might think peptides would represent promising drug treatments, perhaps even a cure, for many infectious diseases. But, alas, they are fundamentally flawed: They are vulnerable to a myriad of enzymes whose job is to rapidly break them down in a way that robs them of their therapeutic properties.

“Because of their vulnerability to enzymatic breakdown, peptides are not ideal drugs. They’re expensive to produce, and yet they must be given in large doses because they disintegrate so quickly,” said Annelise Barron, an associate professor of bioengineering at Stanford School of Engineering.

But, as Barron describes in the journal Pharmaceuticals, she and a team of collaborators have now created peptide-like molecules—which she calls ‘peptoids’—that could circumvent peptides’ shortcomings and turn these new molecules into the basis for an emerging category of antiviral drugs that could treat everything from herpes and COVID-19 to the common cold. Although Barron cautions that years of development and testing remain before these peptoid-based drugs will make it to market, results to date are extremely encouraging.

A better backbone

Peptoids are among a class of biochemicals known as ‘biomimetics’—molecules that mimic the behavior of biological molecules, but with certain key advantages.

Their real-world counterparts, the peptides, are composed of series of bioactive amino acids, known as side chains, bonded in a specific sequence to a long-chain scaffold, known as the peptide backbone. The result is a little like a biomolecular charm bracelet. Unfortunately, the bonds that hold the all-important charms in place are too easily dissolved in the body by the enzymes known as proteases, which digest proteins. When peptides dissolve, their powers vanish.

Peptoids, however, are engineered for durability. Their strength derives from their structure, which is like, and yet fundamentally different from, that of peptides. By altering the underlying backbone and strengthening the bonds that hold the charms in place, Barron’s team has created a way for these antiviral agents to retain the powers that lose when they are degraded by proteases.

“We are excited that our peptoids show great potential as novel antivirals,” Barron said.

Upside potential

In their study, Barron and team chose to focus on the , which is most notable for causing cold sores around the mouth, sexually transmitted infections and even certain forms of blindness. If contracted later in life, herpes can be particularly devastating to its host. Herpes virus brain infections also are associated with Alzheimer’s disease, an active area of research.

The team reviewed a number of prospective peptoids, beginning with a library of 120 molecular structures—which were at that point just chemical symbols on a page. Based on preliminary experiments, they narrowed these to 10 promising candidates, which her team synthesized. Barron then worked with professor Gill Diamond (University of Louisville) to test her newly minted molecules not just for their effectiveness against the herpes virus, but also for their effect on healthy human cells from the exterior surface of the mouth—known as the oral epithelium.

As expected, some of the peptoids showed no effect against the virus. Others were active, but harmful to healthy host cells. But a precious handful of five peptoids proved worthy of additional study. In the end, two hit the sweet spot—defanging the herpes virus while not harming epithelial cells. One of the candidates, in fact, showed “complete” effectiveness against the virus, and that has Barron excited about the possibilities for treating herpes and, perhaps, beyond.

Bursting the bubble

The peptoids work by disrupting the virus’s encapsulating outer membrane. This protective bubble is key to any virus’s ability to insinuate itself into healthy tissues and distribute its harmful DNA into human cells, leading to infection.

“Peptoids destroy the membranes, not just of herpes but other viruses as well. This should give them wide applicability, perhaps even against certain deadly viral infections that currently have no cure,” Barron said.

Barron has since sent samples of peptoids to infectious disease labs around the world asking them to test these new structures against a host of virulent strains, most notably the SARS-CoV-2 that causes COVID-19, but also more familiar viruses like influenza and rhinovirus, the culprit behind the common cold.

“The early reports from my collaborators are very encouraging,” Barron said. “Because our peptoids mimic a very specific human broad-spectrum antiviral peptide—cathelicidin LL-37—we weren’t surprised that they work, but still absolutely delighted to see these results coming in from all around the world.”



More information:
Gill Diamond et al, Potent Antiviral Activity against HSV-1 and SARS-CoV-2 by Antimicrobial Peptoids, Pharmaceuticals (2021). DOI: 10.3390/ph14040304

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Hexbyte Glen Cove 'Ecological disaster' feared as Greece battles forest fire thumbnail

Hexbyte Glen Cove ‘Ecological disaster’ feared as Greece battles forest fire

Hexbyte Glen Cove

More than 270 firefighters have been fighting the blazes on the Geraneia mountain range.

Hundreds of firefighters battled Greece’s first major forest fire of the summer on Saturday, as experts warned of a “huge ecological disaster” in the nature conservation area near Athens.

The , which broke out late Wednesday in the Geraneia mountains some 90 kilometres (55 miles) west of the capital, is “one of the biggest in the past 20 to 30 years, and has come early in the season,” fire chief Stefanos Kolokouris told ANT1 television.

He said better weather conditions allowed firefighters to bring the main front of the outbreak under control late on Friday, but there remain “several active and scattered” blazes.

The ANA national news agency quoted Kolokouris as forecasting that “the situation will be completely under control by tomorrow.”

Government ministers were due in the Gulf of Corinth area Sunday to assess with local officials the extent of the damage and discuss financial aid.

More than 270 firefighters, backed by 16 aircraft and by the army, were fighting the blazes.

No injuries have been reported, but a number of houses have been damaged or destroyed and a dozen villages and hamlets evacuated.

The scale of the damage, notably for farmers, will only be clear once the fire is completely under control, the civil protection agency said.

The blaze started late on Wednesday near the village of Schinos.

But experts and associations quoted in Greek media have warned of an “ecological disaster on an immense scale”.

Some 54 percent of the dense and hitherto protected pine forests have been burnt, the leftist Avghi daily said. And 6.1 percent of the mountain range is part of the European Union’s Natura 2000 network of nature conservation sites.

Euthymios Lekkas, professor of environmental disaster management at the University of Athens, said the fires have burnt more than 55 square kilometres (21 square miles) of and other land, some of it agricultural.

“It’s a huge ecological disaster that needs work to avoid landslides and terrible flooding in the autumn,” he told ERT public television.

The civil protection agency said the blaze started near the village of Schinos next to the resort of Loutraki, apparently by someone burning vegetation in an olive grove.

No injuries were reported but a number of houses were damaged, such as this one at Mavrolimni, west of Athens.

Tortoises and hedgehogs

Smoke from the fire choked Athens with ash falling from the sky.

Rescue associations sought Friday to help injured animals, burned or dehydrated from the fires, bringing food, water and first aid.

One organisation, Caesar’s Paradise, said birds, tortoises, hedgehogs and as well as cats and dogs had been found dead from the smoke and flames.

The Greek NGO ANIMA said it was particularly concerned because the fires erupted “in the spring, when animals give birth to their young”.

“It’s difficult for newborns to run or to fly with their own wings like adults,” the organisation said on social media.

The WWF launched a petition calling on the government to take “serious prevention measures against forest fires”.

Greece faces violent every summer, fanned by dry weather, and temperatures that often soar well above 30 C (86 F).

These may be of natural origin, or criminal, with a view to real estate speculation, or due to negligence.

In 2018, 102 people died in the coastal resort of Mati, near Athens, in Greece’s worst-ever fire disaster.



© 2021 AFP

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‘Ecological disaster’ feared as Greece battles forest fire (2021, May 23)
retrieved 23 May 2021
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Hexbyte Glen Cove Rat killers of New York: dogs, volunteers hunt brazen rodents thumbnail

Hexbyte Glen Cove Rat killers of New York: dogs, volunteers hunt brazen rodents

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Rommel the Jagdterrier holds a dead rat in his mouth after hunting it in a dumpster in lower Manhattan on May 14, 2021.

Late on a Friday night, eight dog enthusiasts and their pet pooches prowl several dark alleys in New York’s Lower East Side with one mission: to hunt and kill as many rats as possible.

The dogs, mostly terriers, pant and strain at their leashes before diving into trash bags and emerging seconds later with a convulsing rodent between their teeth.

“They’re bred for the job. They’re wired for the job. They live for the job,” explained Richard Reynolds, organizer of the Ryders Alley Trencher-fed Society, or R.A.T.S. for short.

New York’s furry rodents are notorious. Legend has it there are as many in the city as humans (some eight million), with public-health officials regularly testing new techniques to control the population, including placing dry ice in rat burrows to asphyxiate them.

Shortly into the coronavirus crisis, America’s Centers for Disease Control and Prevention warned of “unusual or aggressive rodent behavior” after restaurants and offices closed, disrupting .

That hasn’t deterred the men and women volunteers of R.A.T.S. and their dogs. They have been chasing vermin for about 30 years and have maintained their nocturnal meets during the pandemic, albeit slightly less regularly.

Members of The Ryders Alley Trencher-fed Society (R.A.T.S.) searching for vermin on the New York City’s Lower East Side on May 14, 2021.

Superpowers

Shorter-legged dogs such as Jagdterriers flush out rodents from piles of garbage, construction debris and bushes while faster, longer-legged dogs like Bedlingtons stand back, ready to pounce.

“It’s a bit like X-Men,” says Alex Middleton, a 36-year-old dog trainer. “Each dog has its own superpower.”

Reynolds, 77, will sometimes pound trash cans with a metal stick to send rats scurrying, while Middleton frequently drops Rommel, a Jagdterrier, straight into dumpsters.

“Go on Rommel, get it,” the group shouts, as the dog thrashes around in the rubbish. Moments later, following several squeaks, Rommel, blood dripping from his mouth, appears with the rat, and the hunters cheer.

The rat catchers pick up the carcasses by their tails and deposit them in a single-strap fabric bag. Its contents will be emptied and counted at the end of the night.

Lita the wirehaired dachshund holds a dead rat in its mouth after hunting it in a neighborhood in lower Manhattan on May 14, 2021 in New York City.

“The newer members share carrying the bag,” said 28-year-old Sophia Pierce. “It’s heavy—do you want to feel it?”

Pierce, a dog groomer who joined the hunts with her wirehaired dachshund Lita a year ago, is unperturbed by the slaughter.

“You just kind of get used to it. I think the people that just kind of walk up to it get more squeamish than we do,” she said.

Reynolds, a dog-show judge, was in a park in New Jersey in the 1990s when his pooches started killing rats during a show there. The park attendant asked if they would come back to help, and R.A.T.S. was born.

R.A.T.S. answers calls and Facebook messages from rat-troubled residents who are usually most grateful for the group’s swift and effective response.

The city government doesn’t recommend the practice, citing a risk of dogs catching a serious disease known as leptospirosis. But city officials don’t stop the group, because the catchers are not violating its health code.

“The occasional beer can has been thrown at us for making too much noise, but we’ve got a warm welcome most places we go,” said Reynolds.

Alex Middleton stands with Rommel the Jagdterrier after it killed a rat in lower Manhattan on May 14, 2021 in New York City.

‘Different world’

Kayla Callender said she was “hyped” earlier this month when she saw the hunters in her Manhattan neighborhood near the Williamsburg bridge.

“They make a big difference, for sure. I appreciate it,” she told AFP.

Not everyone feels the same.

Animal rights group PETA’s senior director Stephanie Bell described the hunts as “archaic, depraved and illegal.”

But for Reynolds, death-by-terrier is no crueler than by rat poison or sticky traps.

Michael Parsons, a rat expert at Fordham University, likens the hunts to putting “a Band-Aid on cancer.” Reducing food waste and refuse is more effective for controlling the rat population, he said.

But while saying that the group doesn’t make a “heavy impression” on New York’s rodent population, he added that it does “contribute something to the community.”

The group sends DNA samples to universities conducting research and provides frozen rats for falcons to eat at a nearby avian rehabilitation center.

The volunteers say their enjoyment comes from seeing their dogs have fun developing predatory skills.

“We do rat control but that’s not really why we’re here,” said Reynolds. “We’re here for the dogs, to work the dogs.”

Kim McCormick, a 58-year-old paramedic who makes six-hour round trips from Connecticut to take part, also enjoys the camaraderie among owners.

“It’s a whole different world, a whole different way of meeting people. We work together, and the are phenomenal together,” she said.

After three hours of stalking, Greg Conception, 54, lines up the night’s haul on the ground. He counts 26 in total.

“Usually we get about 40. This is a little light. We’re obviously coming here too often,” he said.



© 2021 AFP

Citation:
Rat killers of New York: dogs, volunteers hunt brazen rodents (2021, May 23)
retrieved 23 May 2021
from https://phys.org/news/2021-05-rat-killers-york-dogs-volunteers.html

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part may be reproduced without the written permission. The content is provided for information purposes only.

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Hexbyte Glen Cove As US schools resume testing, large numbers are opting out thumbnail

Hexbyte Glen Cove As US schools resume testing, large numbers are opting out

Hexbyte Glen Cove

Jay Wamsted, left, and his daughter, Kira, are photographed on Thursday, May 20, 2021 in Smyrna, Ga. Wamsted, who is an 8th grade math teacher, allowed his daughter to skip testing this year. With new flexibility from the Biden administration, states are adopting a patchwork of testing plans that aim to curb the stress of exams while still capturing some data on student learning. Credit: AP Photo/Ben Gray

Standardized tests are returning to the nation’s schools this spring, but millions of students will face shorter exams that carry lower stakes, and most families are being given the option to forgo testing entirely.

With new flexibility from the Biden administration, are adopting a patchwork of testing plans that aim to curb the stress of exams while still capturing some data on . The lenient approach means large swaths of students will go untested, shattering hopes for a full picture of how much learning has been set back by the pandemic.

“We will end up with a highly imperfect set of data,” said Robin Lake, director of the Center on Reinventing Public Education at the University of Washington. “This is something our country will have to commit to tracking and learning about for at least the next few years, and maybe the next decade.”

Some of the nation’s largest districts plan to only a fraction of their students as many continue to learn remotely. In New York City, students must opt in to be tested this year. In Los Angeles, most students are not being asked to take state exams this year. Other districts are scaling back questions or testing in fewer subjects.

It’s the latest episode in a long-fought battle over school testing and, as in the past, parents are polarized. Some are demanding tests to get a sense of their children’s progress. Others see no need to put their children through that kind of stress.

Jay Wamsted, right, and his daughter, Kira, are photographed on Thursday, May 20, 2021 in Smyrna, Ga. Wamsted, who is an 8th grade math teacher, allowed his daughter to skip testing this year. With new flexibility from the Biden administration, states are adopting a patchwork of testing plans that aim to curb the stress of exams while still capturing some data on student learning. Credit: AP Photo/Ben Gray

As a teacher, Jay Wamsted believes there’s value in testing. But when his sixth-grade daughter Kira asked to opt out this year, he saw no reason to object. He already knows she needs to catch up on math after months of remote learning. And as a teacher at her school, he knew that many other students were also backing out, undermining the value of the results.

“I know she’s a little behind, and I don’t need that data,” said Wamsted, who live in Smyrna, Georgia. “To take a month to gather data that is not going to mean anything to any of their teachers next year—it seems like a waste of time.”

Parent Abby Norman found her third-grade daughter crying in her bedroom the morning tests were scheduled to begin at her school near Atlanta. Priscilla, 9, had just returned to the classroom after learning remotely and was worried she wasn’t prepared.

Jay Wamsted, right, and his daughter, Kira, are photographed on Thursday, May 20, 2021 in Smyrna, Ga. Wamsted, who is an 8th grade math teacher allowed his daughter to skip testing this year. With new flexibility from the Biden administration, states are adopting a patchwork of testing plans that aim to curb the stress of exams while still capturing some data on student learning. Credit: AP Photo/Ben Gray

“She was so nervous about this test that I don’t care about at all, that does not matter to me,” said Norman, who is a preacher. “I literally ended up telling her, ‘If you want to lick the test and give it back, I don’t care.'”

With that reassurance, Abby agreed to take the tests and scored “almost off the charts,” her mom said. Still, Norman resents that students were put in that situation at all.

Several states lobbied the Biden administration to cancel standardized tests entirely for a second year, but the Education Department aimed for a middle ground: It told states to test as many student as possible without requiring them to come in just for exams. The goal, the agency said, should be to measure the pandemic’s impact and identify how to help students recover.

Acknowledging the challenges of the pandemic, the agency invited states to shorten or delay tests, and it urged them to ease the stakes for students. But the department later granted additional leniency to certain states, prompting criticism that it failed to set a clear bar.

Abby Norman talks with her 9-year-old daughter Priscilla after she arrived home from school to the family’s Decatur, Ga., home on Tuesday, May 18, 2021. Priscilla was in tears the first morning of testing because she felt pressure to do well, but didn’t feel prepared after remote learning. Credit: AP Photo/Ben Gray

Washington, D.C., was granted permission to cancel tests because 88% of students were learning remotely, but the agency rejected similar requests from Michigan, New York and Georgia. Requests to scale back testing were granted in Colorado and Oregon, but a plan to narrow the testing pool in Washington state was rejected.

Those who opposed testing say it’s the last thing students need after such a challenging year. Schools have other ways to evaluate students, they say, and testing only takes away from classroom time.

Michigan’s education chief has blasted the uneven flexibility granted to states. School across Michigan have already used other tests to assess students, he said, and more exams “will inform precisely nothing about our children’s needs.” State officials in New York argued that testing is unlikely to produce useful data given the variability in instruction during the pandemic.

Jay Wamsted, left, and his daughter, Kira, are photographed on Thursday, May 20, 2021 in Smyrna, Ga. Wamsted, who is an 8th grade math teacher, allowed his daughter to skip testing this year. With new flexibility from the Biden administration, states are adopting a patchwork of testing plans that aim to curb the stress of exams while still capturing some data on student learning. Credit: AP Photo/Ben Gray

“In fact, the students most in need of state assessments—those receiving remote instruction—are the very children who are not required to take the test,” the state’s top education officials wrote in an April statement.

Testing advocates counter that there’s still value in collecting as much data as possible. Lake, at the University of Washington, said even imperfect results can help illuminate the scope of the problem schools face as they help students recover.

“Standardized tests at the state level are the most consistent data we’ve had to track academic progress, so it would be a huge missed opportunity to forgo those tests this year,” she said. “Flying blind is not a responsible position for a public official to take.”

Some critics blame the Biden administration for allowing halfhearted attempts at evaluations. They point to places like New York City, where the outgoing schools chief urged parents in February to consider opting out of tests. Oregon’s two largest districts have voted to defy state orders and skip testing. The state says their penalty will be to submit a plan to come into compliance next year.

Jay Wamsted, right, and his daughter, Kira, are photographed on Thursday, May 20, 2021 in Smyrna, Ga. Wamsted, who is an 8th grade math teacher allowed his daughter to skip testing this year. With new flexibility from the Biden administration, states are adopting a patchwork of testing plans that aim to curb the stress of exams while still capturing some data on student learning. Credit: AP Photo/Ben Gray

“These states are simply playing games. They’re not even pretending to make an effort to test students, and the Biden administration is letting them get away with it,” said Michael Petrilli, president of the Thomas B. Fordham Institute, a conservative education think tank.

If testing isn’t feasible now, Petrilli said, it should be done in the fall. Maryland, New Jersey and Washington state have postponed tests, and it’s an option for districts in California.

In some states, officials are pushing ahead with tests much as they have in the past. In Tennessee and Arkansas, education officials have said all healthy students are expected to take state exams, which are only being offered in-person. More than 1.4 million tests have already been given in Arkansas this spring, and the state is on track to test at least 95% of students, according to the state’s .

  • Abby Norman, right, and her 9-year-old daughter Priscilla Norman, left, pose at the family’s home in Decatur, Ga., Tuesday, May 18, 2021. Norman said Priscilla was in tears the first morning of school testing because she felt pressure to do well, but didn’t feel prepared after remote learning. Credit: AP Photo/Ben Gray
  • Abby Norman, right, looks at a project made by her daughter Priscilla, 9, left, as Juliet, 11, runs inside as they arrive home from school to the family’s home in Decatur, Ga., Tuesday, May 18, 2021. Priscilla was in tears the first morning of school testing this year because she felt pressure to do well, but didn’t feel prepared after remote learning. Credit: AP Photo/Ben Gray
  • Abby Norman greets her daughters Juliet, 11, left, and Priscilla, 9, as they arrive home from school to the family’s Decatur, Ga. home on Tuesday, May 18, 2021. Priscilla was in tears the first morning of testing this year because she felt pressure to do well, but didn’t feel prepared after remote learning. Credit: AP Photo/Ben Gray
  • Abby Norman greets her daughters Juliet, 11, left, and Priscilla, 9, as they arrive home from school to the family’s Decatur, Ga., home on Tuesday, May 18, 2021. Priscilla was in tears the first morning of testing this year because she felt pressure to do well, but didn’t feel prepared after remote learning. Credit: AP Photo/Ben Gray
  • Abby Norman, right, said her 9-year-old daughter Priscilla Norman, left, was in tears the first morning of school testing because she felt pressure to do well, but didn’t feel prepared after remote learning, sitting outside at the family’s home in Decatur, Ga., Tuesday, May 18, 2021. Credit: AP Photo/Ben Gray

In normal years, the federally required tests are used to gauge school effectiveness and chart the progress of students, both as individuals and in demographic groups. In some states, students must pass certain tests to move to the next grade or graduate from high school. But this year, most states are focusing on measuring growth and letting schools and students off the hook for the results.

After last year’s tests were canceled, there was hope that this year’s exams would provide the most comprehensive look yet at the pandemic’s impact on education. But the inconsistency between states now makes a broad analysis impossible, said Scott Marion, executive director of the nonprofit Center for Assessment, which helps states design and evaluate tests.

Still, he believes the results will have value. As schools begin the long process to help students recover, he said, this year’s data will provide a foundation to measure against.

“I do think the data can be a useful baseline going forward,” he said. “If this is the low point, or close to it, how are our kids going to come out of it going forward?”



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As US schools resume testing, large numbers are opting out (2021, May 23)
retrieved 23 May 2021
from https://phys.org/news/2021-05-schools-resume-large-opting.html

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Hexbyte Glen Cove University of Montana students lead prescribed wildfire burn on university ranch thumbnail

Hexbyte Glen Cove University of Montana students lead prescribed wildfire burn on university ranch

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A UM student and wildland firefighter walks on UM’s Bandy Ranch in April during a prescribed burn event hosted by the University. The prescribed burn took two years to plan and included several UM FireCenter staff, students and professors. Credit: University of Montana

In mid-April on the University of Montana-owned Bandy Ranch in neighboring Powell County, the snow was still visible on the surrounding Garnet Mountains, geese were honking overhead and Cottonwood Creek was beginning to ripple.

But there would be a greater sound of the season that day.

Tree sap, water pockets and air popping, crackling and combusting from heat, and the swinging of Pulaski’s into hard ground as bright orange flames raced up conifers against a backdrop of radio static and beeps.

“The first rule of fire is that it depends on batteries,” said LLoyd Queen, UM professor and director of UM’s FireCenter. “Everything runs on batteries—headlamps, radios, weather stations.”

Prescribed fires consist of purposely burning land to reduce the risk of wildfire and jumpstart rejuvenation of plant life. It was the University’s first-time hosting a cross-boundary prescribed fire, burning both UM property and adjacent land managed by other agencies.

As the world faces bigger and scarier wildfires, researchers and fire managers working together to prevent and manage them represents of a new trend in fire science, Queen said.

The day also doubled as a hot and heavy training experience for UM students, who were front and center on the burn.

“The burn has two objectives—one is ecological, one is educational,” Queen said. “The first is restoring the landscape, getting rid of debris and the second is providing an educational experience for students and partners on the burn.”

Queen was one of several Fire Center staff and UM professors in the W.A. Franke College of Forestry and Conservation who joined forces with fire scientists from the Missoula Fire Sciences Laboratory, a research institute with the U.S. Forest Service, and personnel from Montana Fish, Wildlife and Parks to manage the burn, which took about two years to plan. At about 3,500 acres, UM’s Bandy Ranch is a working cattle ranch that also serves as an exploratory extension of a classroom.

“This is a complicated prescribed burn, given the involvement of our students and combination of jurisdictions and research activities,” said Carl Seielstad, UM Fire and Fuels Program manager and associate professor. “We’ve got students, University property that’s part of the Montana Forest and Conservation Experiment Station, the Forest Service and Montana FWP, all of whom are heavily and intimately involved.”

Seielstad, who authored the burn plan and secured the required permissions for the fire, served as the day’s incident commander or burn boss—or the main guy in charge if anything went wrong.

“From a fire management perspective, we are successful when executed safely, the burn doesn’t get out of control and the treatment meets the objectives of the burn plan,” Seielstad said.

The day’s charge included the lighting by drip torch of about 108 acres of native grassland and beetle-killed pine trees that included equal parts of Bandy Ranch, research plots from the Forest Service and the Montana FWP game range adjacent to the ranch.

Management of the fire also included a mix of 12 UM undergraduate and graduate students who either are members of the UM Fire Club, majoring in forestry or completing a minor in Fire Sciences and Management. One of the squad bosses included a graduate student in UM’s Computer Science Department who studies fire behavior models when not fighting fire.

Several UM students from the UM Fire Club, many of whom are students in the W.A. Franke College of Forestry and Conservation, volunteered for the burn to receive prescribed burn experience for Red Card certifications. Credit: University of Montana

The majority of students have summer jobs as wildland firefighters, and many were on hand that day to receive certification for experience on a prescribed burn for their Red Cards, agency-issued documents that certify that an individual has the training, experience and fitness to perform duties as a wildland firefighter.

“It’s a super fun and a really great opportunity to be out here, to be able to have this experience, particularly before many of us fight fire this summer,” said Mason Banks, president of UM’s Fire Club and driver of the “gator,” an all-purpose all-terrain vehicle, that day.

As Missoula and UM both serve as a national nexus of wildland fire expertise, the burn also served as an opportunity for a host of research for interagency and University research objectives with important implications for national wildfire prediction, response and management.

Some of those projects included examining modifications of fuel structure with fire behavior, capturing 3-D images for fire prediction models, better understanding how fire kills trees immediately and in the long-term documenting how energy and fuels interact for computer science models.

Russell Parsons, research ecologist with the Forest Service, was on the burn to capture footage via ground-based remote cameras to document the fire’s behavior, complementing aerial imagery captured by drone-based sensors flown by UM scientists.

“The drone allows us to see exactly what the fire is doing, down to the second,” Parsons said. “The footage will allow us to track thermal heat and watch that progression over space and time, which we plan to recreate in a computer model.”

As the country continues to see super wildfires, computational models of fire behavior can help predict fire dynamics and inform on-the-ground management and response. Parsons said the models have a particularly important role in helping managers consider different options and evaluate how prescribed fires or fuel treatments can help control fire. Parsons said he ultimately hopes to use the data to create simulation training for wildland firefighters.

“As we continue to see extreme droughts and high temperatures, we know wildfire is not going to get better, it’s going to get worse,” he said. “So, what we can do in the meantime is to model the fire so we can try to predict fuel and fire interactions in varying environments.”

Maggie Epstein, UM forestry graduate student and squad boss that day, was responsible for the safety of the firefighters and reporting directly to the fire boss. Epstein had to manage the day’s variables, including wind, fuels and moisture and delivered orders to the fire crew.

“I’m mostly in a lab between four and five days a week, so it’s nice to get out and be on the line today,” she said. “It’s exciting to be part of burn that includes so many moving parts, objectives and agencies.”

As some parts of the fire petered out throughout the day, other areas jumped irrigation ditches and spot fires ignited outside of the containment line, adding for a bit of drama that the crew was fully prepared and trained to expect.

“Keeping fire within control lines is paramount, but threats like this are expected, planned for and they provide a learning opportunity to assess what we could change in the future to avoid these spot fires,” said Queen.

Queen said what sets UM’s expertise in fire sciences apart is that most, if not all FireCenter faculty and staff, serve as wildland firefighters when they’re not teaching or researching.

“It’s immensely important for us to not only serve as experts in the discipline, but to never lose that practice and connection with the field,” he said. Ryan Kirk, a UM freshman from Eugene, Oregon, who is majoring in business, was also working the fire that day in preparation for spending the summer as a wildland firefighter in Wyoming.

“I’m glad to have this experience on my card, and I love being out here with other Fire Club volunteers,” he said. “A big reason why I chose UM is for these kinds of experiences. I can’t say working is easy or the hours aren’t long, but it’s always fun. Addicting, actually.”



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University of Montana students lead pres

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Hexbyte Glen Cove Clues from soured milk reveal how gold veins form thumbnail

Hexbyte Glen Cove Clues from soured milk reveal how gold veins form

Hexbyte Glen Cove

McGill Colloidal Au research team study a mineralized (gold-bearing) vein underground at the Brucejack mine. Credit: Duncan McLeish

For decades scientists have been puzzled by the formation of rare hyper-enriched gold deposits in places like Ballarat in Australia, Serra Palada in Brazil, and Red Lake in Ontario. While such deposits typically form over tens to hundreds of thousands of years, these “ultrahigh-grade” deposits can form in years, month, or even days. So how do they form so quickly?

Studying examples of these deposits from the Brucejack Mine in northwestern British Columbia, McGill Professor Anthony Williams-Jones of the Department of Earth and Planetary Sciences and Ph.D. student Duncan McLeish have discovered that these gold deposits form much like soured milk. When milk goes sour, the butterfat particles clump together to form a jelly.

Q&A with Anthony Williams-Jones and Duncan McLeish

What did you set to find out?

Scientists have long known that gold deposits form when hot water flows through rocks, dissolving minute amounts of gold and concentrating it in cracks in the Earth’s crust at levels invisible to the naked eye. In rare cases, the cracks are transformed into veins of solid gold centimetres thick. But how do fluids with such low concentrations of gold produce rare ultrahigh-grade gold deposits?

What did you discover?

Our findings solve the paradox of “ultrahigh-grade” or “bonanza” gold formation, which has frustrated scientists for over a century. The paradox of bonanza gold deposits is that there is simply not enough time for them to form, they should not exist, but they do!

McGill Professor Anthony (Willy) Williams-Jones and Pretium Resources Inc. geologist Joel Ashburner study a mineralized (gold-bearing) vein on surface at the Brucejack mine. Credit: Duncan McLeish

As the concentration of gold in hot water is very low, very large volumes of fluid need to flow through the cracks in the Earth’s crust to deposit mineable concentrations of gold. This process would require millions of years to fill a single centimetre wide crack with gold, whereas these cracks typically seal in days, months, or years.

Using a powerful electron microscope to observe particles in thin slices of rock, we discovered that bonanza gold deposits form from a fluid much like milk. Milk consists of little butterfat particles that are suspended in water because they repel each other, like the negative ends of two magnets. When the milk goes sour the surface charge breaks down, and the particles clump together to form a jelly. It is the same with gold colloids, which consist of charged nanoparticles of gold which repel each other, but when the charge breaks down, they “flocculate” to form a jelly. This jelly gets trapped in the cracks of rocks to form the ultra high-grade gold veins. The gold colloids are distinctively red and can be made in the lab, whereas solutions of dissolved gold are colourless.

Why are the results important?

We produced the first evidence for gold colloid formation and flocculation in nature and the first images of small veins of gold colloid particles and their flocculated aggregates at the nano-scale. These images document the process by which the cracks are filled with gold and, scaled up through the integration of millions of these small veins, reveal how bonanza veins are formed.

How will this discovery impact the mining industry?

Ultra-high-grade (bonanza) occurrence of gold in exploration drill core from the Brucejack mine. Credit: Pretium Resources Inc.

Our results are important to the and in Canada and around the world. Now that we finally understand how bonanza deposits form, mineral exploration companies will be able to use the results of our work to better explore for bonanza deposits as well as gold deposits. Genetic studies of Canada’s most fertile metallogenic districts—such as the one we have just completed at Brucejack—are required to improve our understanding of how world-class mineral deposits form, and thereby develop more effective strategies for their exploration.

What’s next for this research?

We suspect that the colloidal processes that operated at Brucejack and other bonanza gold systems may also have operated to form more typical . The challenge will be to find suitable material to test this hypothesis. At Brucejack, the next step will be to better understand the reasons why colloid formation and flocculation occurred on the scale observed and reconstruct the geological environment of these processes. We have also been preparing colloids in the lab in an attempt to simulate what we discovered at Brucejack.



More information:
Duncan F. McLeish et al, Colloidal transport and flocculation are the cause of the hyperenrichment of gold in nature, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2100689118

Citation:
Clues from soured milk reveal how gold veins form (2021, May 21)
retrieved 22 May 2021
from https://phys.org/news/2021-05-clues-soured-reveal-gold-veins.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.

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Hexbyte Glen Cove New research examines why some firms prepare for natural disasters and others don't thumbnail

Hexbyte Glen Cove New research examines why some firms prepare for natural disasters and others don’t

Hexbyte Glen Cove

Credit: Unsplash/CC0 Public Domain

Despite the increasing frequency and severity of floods, storms, wildfires and other natural hazards, some firms in disaster-prone areas prepare while others do not.

That issue was examined in a new study by Jennifer Oetzel, professor, American University and Chang Hoon Oh, William & Judy Docking Professor of Strategy, University of Kansas published in the Strategic Management Journal (SMJ).

“Due to the increased frequency and severity of floods, storms, epidemics, wildfires and other anticipated over the coming decades (according to the National Oceanic and Atmospheric Administration), there is growing pressure on managers and their firms to develop strategies for managing natural disaster risk,” write the researchers.

“Preparing for future events that may never occur is challenging. Day-to-day events tend to crowd out long-term planning, but business continuity depends on managers anticipating and planning for large scale disasters. For these reasons, our goal in this study was to understand the antecedents associated with disaster preparation so that managers can better prepare for .”

They defined disaster preparedness as the acquisition of the skills and capabilities needed to reduce damage to a firm, to minimize disruption to the supply chain, and more generally, and to save lives and protect employees.

Disaster preparedness can entail a wide variety of initiatives including conducting an assessment of firm vulnerability to natural disasters, establishing a natural disaster response plan, training employees about natural , purchasing insurance, developing a business continuity plan, and arranging to move business operations temporarily to another location, among others.

Emergency preparedness pays off. A review conducted by the Wharton Risk Center that focused on floods suggested that for every dollar spent on flood risk reduction, on average, five dollars is saved through avoided and reduced losses. But despite the documented value of preparing, most firms fail to do so.

“Since not all firms located in disaster prone areas prepare for disasters, what are the antecedents to disaster preparation? To answer this question,” write the authors, “we looked at several factors that are likely to affect whether or not businesses will prepare. The first factor is organizational experience with disaster, which can be a transformational and powerful motivator for change when managers see the value of disaster preparation and planning.”

The mechanisms driving the relationship between experience and preparedness are multifaceted. Managers may fail to learn from past experiences if they do not consider a recently experienced disaster as representative of future events. Even when managers learn from experience and see preparation as valuable, they may lack the organizational influence and find that they are unable to leverage learning to inform decision-making.

Aside from experience, strategic decisions around disaster preparation are likely to be affected by managers’ subjective judgments and/or knowledge about disaster risks. Depending upon the nature of their experience, managers may either over- or under-estimate disaster risk and thus over or under prepare.

Research has also shown that willingness to learn from other organizations about how to manage natural disaster risk is also important. External sources of information provide different perspectives and may help organizations to avoid internal biases in decision making.

“Another set of factors that are presumed to affect preparation are the characteristics of disasters, including their type, frequency, and impact,” write the researchers. “Historical records and scientific data indicate whether or not a given location is subject to natural disasters and, if so, of what type.

“Natural scientists examining climate change trends are raising concerns, however, that past experiences may not be predictive of the future. In certain geographic areas (e.g., Houston, Texas), the frequency of major disasters may be increasing substantially, deviating significantly from the past.”

In conducting two studies—an international survey in 18 disaster-prone countries and a U.S. survey in New York City and Miami—Oetzel and Oh found that managers are more likely to prepare when their companies experienced prior disasters. The likelihood of preparedness is even higher when companies work with and learn from other organizations and stakeholders.

“Managers operating in locations characterized by high impact, low frequency disasters are more willing to learn from others,” they wrote. “In contrast, managers in areas characterized by low impact, high frequency , are more likely to prepare alone. Since effective disaster preparation typically entails working with, and learning from others, those companies that choose a go-it-alone strategy may misjudge disaster risk.”

The SMJ is published by the Strategic Management Society (SMS), comprised of 3,000 academics, business practitioners, and consultants from 80 countries, focuses on the development and dissemination of insights on the strategic management process, as well as on fostering contacts and interchanges around the world.



More information:
Jennifer Oetzel et al, A storm is brewing: Antecedents of disaster preparation in risk prone locations, Strategic Management Journal (2021). DOI: 10.1002/smj.3272

Provided by
Strategic Management Society

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Hexbyte Glen Cove Research suggests fly brains make predictions, possibly using universal design principles thumbnail

Hexbyte Glen Cove Research suggests fly brains make predictions, possibly using universal design principles

Hexbyte Glen Cove

Flies make exceptionally fast escape maneuvers in response to visual threats (pink star). The behavior unfolds so rapidly that there is not time for vestibular (haltere) or visual feedback to control flight. Visual prediction that flows through the vertical sensing system’s “information bottleneck” may help control flight in this open-loop interval. This information could flow directly to the wing steering muscles, as an instantiation of the so-called “control-loop” hypothesis. Credit: This image was created by authors S.E. Palmer and S. Wang, with 3D fly illustrations from D.A. Drummond.

Flies predict changes in their visual environment in order to execute evasive maneuvers, according to new research from the University of Chicago. This reliance on predictive information to guide behavior suggests that prediction may be a general feature of animal nervous systems in supporting quick behavioral changes. The study was published on May 20 in PLOS Computational Biology.

Animals use their sensory nervous systems to take in about their environments and then carry out certain behaviors in response to what they detect. However, the takes time to process this , meaning that the environment can change by the time the previous information has been fully processed.

“This is really important in predator/prey interactions,” said senior author Stephanie Palmer, Ph.D., Associate Professor of Organismal Biology and Anatomy at UChicago. “For a fly, everything is trying to eat you, and you want to avoid being eaten. However, the fly’s environment is rapidly changing, and the neurons they have are laggy. We wanted to study how were able to execute quick evasive behaviors to avoid being eaten by predators when ongoing feedback from their sensory systems hasn’t been processed.”

To answer this question, the investigators took a highly interdisciplinary approach. “This is a project born out of this new era of open science sharing,” Palmer said. “We were able to take the precise behavioral recordings made by another group and use them for a theoretical, computational neuroscience question: Does the fly’s visual system make predictions using the initial detection of a threat that can span the lag time in processing of additional feedback as the fly starts its evasive behavior?”

Previous work from first author Siwei Wang, Ph.D., a postdoctoral researcher in Palmer’s group, looked at a theoretical model of how encoding motion in the fly visual system might work. “I had an idea of how to extend these ideas to prediction, and this study allowed me to compare my model to real life behavioral data to test my theory,” Wang said.

Using detailed diagrams of the connectivity between neurons in the fly visual system, the researchers made a simulation of the visual response as they fed in the previously recorded behavioral data set. “We compared what an optimal prediction would look like and what the fly’s prediction looks like, and then we broke open the simulation to try to identify which parts were the most important for making these predictions,” Palmer said.

The authors first identified that sensory data about the fly’s visual world passes though an information bottleneck, where some of the sensory data is thrown out by the fly’s brain because it simply does not have enough computing power to handle the amount of information it is taking in. However, the fly cannot indiscriminately discard visual information, because some of it might be useful for making predictions.

The authors identified structures called axonal gap junctions, which are physical channels connecting the neurons, that mediate an optimal form of this information bottleneck and are critical for both filtering out the unnecessary information and preserving the necessary information to make predictions.

The investigators further found that a subpopulation of these vertical motion sensory neurons that are involved in making predictions is unique in that it is also directly connected to the fly’s flight steering neurons. This suggests that there is direct input from the neurons responsible for making predictions about the fly’s environment to neurons that control the fly’s behavior. This might explain how predictions that the fly is making are able to quickly influence its behavior.

Identification of these structures and the ability of the fly visual system to make predictions is likely to drive insight into how other animals’ nervous systems make similar predictions.

“Cracking open the black box of how the fly does this has revealed what we think are universal design principles that the nervous systems of other animals probably also use,” Palmer said. “We’re interested in searching for another example of -guiding behavior in another animal and asking if what we found in the fly really does apply broadly across species.”

Ultimately, this kind of theoretical neuroscience may shed light on how our human brains function. “One of our greatest challenges as humans is understanding how everything inside our head works. Insights from work on flies can be generalizable and actually give us clues to how our brains operate,” Palmer said.

Wang said the results could even have implications for understanding neurodegenerative diseases like Alzheimer’s disease, where the brain loses the ability to make predictions. If the insights gained from these fly studies hold true in humans, it could help uncover new specific targets for therapeutic intervention. “We’re still a long way from that, but this research in flies is setting the ground work to allow others to do that down the line,” Wang said.



More information:
Siwei Wang et al, Maximally efficient prediction in the early fly visual system may support evasive flight maneuvers, PLOS Computational Biology (2021). DOI: 10.1371/journal.pcbi.1008965

Citation:
Research suggests fly brains make predictions, possibly using universal design principles (2021, May 20)
retrieved 21 May 2021
from https://phys.org/news/2021-05-brains-possibly-universal-principles.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced

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Hexbyte Glen Cove An updated understanding of how to synthesize value-added chemicals thumbnail

Hexbyte Glen Cove An updated understanding of how to synthesize value-added chemicals

Hexbyte Glen Cove

Credit: CC0 Public Domain

Researchers have long been interested in finding ways to use simple hydrocarbons, chemicals made of a small number of carbon and hydrogen atoms, to create value-added chemicals, ones used in fuels, plastics, and other complex materials. Methane, a major component of natural gas, is one such chemical that scientists would like to find to ways to use more effectively, since there is currently no environmentally friendly and large-scale way to utilize this potent greenhouse gas.

A new paper in Science provides an updated understanding of how to add onto simple hydrocarbons like methane. Conducted by graduate students Qiaomu Yang and Yusen Qiao, postdoc Yu Heng Wang, and led by professors Patrick J. Walsh and Eric J. Schelter, this new and highly detailed is a crucial step towards designing the next generation of catalysts and finding scalable approaches for turning greenhouse gases into value-added chemicals.

In 2018, a paper published in Science described a mechanism for adding functional groups onto methane, ethane, and other hydrocarbons at room temperature using a cerium-based photocatalyst. The ability to use earth-abundant metals like cerium to create value-added chemicals was an exciting prospect, the researchers say. However, there were aspects of this study that Schelter and his group, who have been working with cerium for a number of years, wanted to understand more thoroughly.

“There were some things in the original paper that we thought were interesting, but we didn’t necessarily agree with the conclusions based on the data that they were reporting,” Schelter says. “We had an idea that what was happening in terms of the mechanism of the reaction, the steps that were involved, and the catalyst that was operative for their chemistry was different from what they were reporting.”

To run the experiments and collect the data they would need to support a new hypothesis, Schelter and Walsh applied for a seed grant from the University of Pennsylvania’s Vagelos Institute for Energy Science and Technology. This funding supported a new collaboration between Schelter and Walsh, allowing the researchers to purchase specialized equipment and hire Yu Heng Wang, a former Penn postdoc who is now an assistant professor at National Tsinghua University in Taiwan.

Thanks to the Vagelos Institute support, the Schelter and Walsh groups were able to combine their complementary expertise in inorganic and and to conduct experiments to obtain data required to propose a new mechanism. This included synthesizing new chemicals, studying reaction rates, looking at how the photocatalyst reacted with different isotopes, and computational analysis. The researchers also isolated the proposed reaction intermediate and were able to obtain its crystal structure, an additional challenge considering that many of the compounds in this study were highly air- and moisture-sensitive.

“We are using conventional techniques to understand the system better and to give a clear mechanism,” Yang says about their approach. “Here, we are mostly using the inorganic perspective with different techniques to understand the mechanisms of the organic reaction. So, it’s a collaboration of inorganic and organic perspectives to understand the mechanism.”

After more than two years of work, the researchers were able to propose a revised mechanism that highlights the essential role of chlorine atoms. While the previous study implicated an alcohol-based intermediate, this latest study found that chlorine radicals, atoms with unpaired electrons that make them highly reactive, form a selective “trap” in the photocatalyst that can give rise to different products.

“I think the hardest part was to understand why the reactivity was happening, and we had to approach that with some unconventional thinking of these intermediate complexes,” says Walsh. “The behavior of the intermediates fits a pattern that people attribute to a radical based on oxygen, but in fact it’s really a chlorine radical that’s the active species, activating the alcohol to make it look like it’s a radical derived from the alcohol.”

Having a detailed understanding of this chemical reaction is a crucial step towards improving existing catalysts and making these and other chemical reactions more efficient. “In order to rationally develop the next generation of catalysts, we have to understand what the current generation is doing,” says Walsh. “With this information, we and others can now build on this revised mechanism and reaction pathway to push the science forward.”

And while there is more work to be done towards finding a fast, scalable reaction for methane transformation, having a detailed understanding of the mechanisms that drive this specific reaction is essential to both reducing greenhouse gas emissions and being able to use methane to create value-added products, the researchers say.

“Chemistry is at its most elegant when we can refine knowledge through expanded insight,” says Schelter. “The contribution here is about getting the right model and using it to advance to the next generation of catalysts that will be even better than the current one.”



More information:
“Photocatalytic C–H activation and the subtle role of chlorine radical complexation in reactivity” Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abd8408

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Hexbyte Glen Cove Thin is now in to turn terahertz polarization thumbnail

Hexbyte Glen Cove Thin is now in to turn terahertz polarization

Hexbyte Glen Cove

Ultrathin, broadband polarization rotators are made possible by ultrathin carbon nanotube films developed at Rice University in 2016. The films of highly aligned single-walled nanotubes were first made in 2016. Credit: Kono Laboratory/Rice University

It’s always good when your hard work reflects well on you.

With the discovery of the giant rotation of light, that is literally so.

The ultrathin, highly aligned carbon nanotube films first made by Rice University physicist Junichiro Kono and his students a few years ago turned out to have a surprising phenomenon waiting within: An ability to make highly capable terahertz polarization rotation possible.

This rotation doesn’t mean the films are spinning. It does mean that polarized light from a laser or other source can now be manipulated in ways that were previously out of reach, making it completely visible or completely opaque with a device that’s extremely thin.

The unique optical rotation happens when linearly polarized pulses of light pass through the 45-nanometer film and hit the silicon surface on which it sits. The light bounces between the substrate and film before finally reflecting back, but with its polarization turned by 90 degrees.

This only occurs, Kono said, when the input light’s polarization is at a specific angle with respect to the nanotube alignment direction: the “magic angle.”

The discovery by lead author Andrey Baydin, a postdoctoral researcher in Kono’s lab, is detailed in Optica. The phenomenon, which can be tuned by changing the refractive index of the substrate and the film thickness, could lead to robust, flexible devices that manipulate .

Rice University physicists have made unique broadband polarization rotators with ultrathin carbon nanotube films. The films optically rotate polarized light output by 90 degrees, but only when the input light’s polarization is at a specific angle with respect to the nanotube alignment direction: the “magic angle.” Credit: Kono Laboratory/Rice University

Kono said easy-to-fabricate, ultrathin broadband polarization rotators that stand up to high temperatures will address a fundamental challenge in the development of terahertz optical devices. The bulky devices available until now only enable limited polarization angles, so compact devices with more capability are highly desirable.

Because easily passes through materials like plastics and cardboard, they could be particularly useful in manufacturing, quality control and process monitoring. They could also be handy in and for security screening, because many materials have unique spectral signatures in the terahertz range, he said.

“The discovery opens up new possibilities for waveplates,” Baydin said. A waveplate alters the polarization of light that travels through it. In devices like terahertz spectrometers used to analyze the molecular composition of materials, being able to adjust polarization up to a full 90 degrees would allow for data gathering at a much finer resolution.

“We found that specifically at far-—in other words, in the terahertz frequency range—this anisotropy is nearly perfect,” Baydin said. “Basically, there’s no attenuation in the perpendicular polarization, and then significant attenuation in the parallel direction.

“We did not look for this,” he said. “It was completely a surprise.”

He said showed the effect is entirely due to the nature of the highly aligned nanotube , which were vanishingly thin but about 2 inches in diameter. The researchers both observed and confirmed this giant polarization rotation with experiments and computer models.

“Usually, people have to use millimeter-thick quartz waveplates in order to rotate polarization,” said Baydin, who joined the Kono lab in late 2019 and found the phenomenon soon after that. “But in our case, the film is just nanometers thick.”

“Big and bulky waveplates are fine if you’re just using them in a laboratory setting, but for applications, you want a compact device,” Kono said. “What Andrey has found makes it possible.”



More information:
Andrey Baydin et al, Giant terahertz polarization rotation in ultrathin films of aligned carbon nanotubes, Optica (2021). DOI: 10.1364/OPTICA.422826

Citation:
Thin is now in to turn terahertz polarization (2021, May 20)
retrieved 21 May 2021
from https://phys.org/news/2021-05-thin-terahertz-polarization.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.

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