Researchers report finding first bidirectional color-changing flower variety

Flowers show their true colors
A magnified image clearly showing the alternating orange and pink colors of the flower petals. Credit: ©2022 H. Tsukaya CC-BY

We all like flowers, and one of the most appealing things about flowers is presumably the wide array of shapes, sizes, and of course, colors in which they come. But did you know that some flowers can change their colors? Although it’s not all flowers, this trait has been observed in hundreds of different species for at least a number of decades.

It’s thought that -changing flowers do so because it signals to pollinating insects that the flower is ready to supply nectar or pollen which rewards them. This is considered to be an “honest” signal.

But the reverse can also be seen; some plants show a “dishonest” signal, with some of their flowers displaying their default color while others display their signal color. That behavior is thought to increase the overall visibility of the plant from a distance to would-be pollinators.

Whatever the strategy of the plant in question, all examples of color-changing flowers found have been unidirectional: Once the color has changed, it does not change back. So, imagine the surprise University of Tokyo Professor Hirokazu Tsukaya must have felt when he saw a flower of the plant Causonis japonica change color, and then change again, and again.

“Even though I’ve studied this plant in detail, having discovered there were at least two varieties back in 2000, the bidirectional color-changing flowers were a completely unexpected finding,” said Tsukaya.

“My colleague Professor Nobumitsu Kawakubo from Gifu University is an expert in time-lapse, long-period video recordings of pollinating flowers. He and his student originally tried to explore the pollinating behaviors between the different kinds of Causonis japonica and expected to see the familiar change from its default orange color to bright pink. But they couldn’t believe it when they reviewed the time-lapse video and saw that it not only changed back to orange again, but that this change oscillated between the two states. They informed me on this finding; this compelled us to find out why. So we started a collaboration.”






The unique bidirectional color-changing petals were only observed now because in nature, the plant is a chaotic bundle of buds, leaves and flowers that grows quite rapidly. So, it was not really possible to track individual flowers over time. But thanks to carefully controlled time-lapse video recording, now individual flowers can be tracked and hence lead to observations such as this one. Credit: ©2022 H. Tsukaya CC-BY

Thanks to the carefully captured time-lapse videos from the field and detailed observations in the laboratory, Tsukaya managed to connect which physiological changes took place in the flowers concurrent with their changes in colors.

“The initial orange state is coincident with the male stage of the flower’s , when it is secreting nectar,” said Tsukaya.

“When the stamen—male part—becomes old and detaches, the flowers turn pink. Mere hours later, the pistil—female part—begins to mature, secretes nectar, and the flower turns orange again. Once that stage is over, the flower fades to pink. The main chemical responsible for the color changing is orange-yellow ; its cycle of accumulation and degradation is also the fastest known to date. That fact was another surprise to us.”

The chemical name carotenoid sounds a little like the word “carrot.” This is not a coincidence, as the same chemical is what gives typical carrots their orange hue. It’s a good source of vitamin A, and given the color-changing show the most rapid accumulation of carotenoids ever seen, it’s no surprise the researchers think their discovery might have some future application in developing carotenoid-containing vegetables that mature faster or contain higher yields of beneficial vitamins.

“Our next steps will be to find out what is governing the behaviors we have observed,” said Tsukaya.

“One big question we have is: At what level are the stages of the cycles regulated? Is it caused by proteins caught in a feedback cycle, or does something occur on a genetic level? We will continue to explore this and hope to find an explanation soon. It’s strange to think that several hundred years ago, agriculturalists in Japan hated Causonis japonica because of its vigorous nature. But a novelist, Kyoka Izumi, wrote about them so favorably, I wonder if it helped maintain some interest in preserving them. Whatever the reason, I’m glad they are around now to share their secrets with us. I wonder what we’ll discover next.”

The study appears in the journal Scientific Reports.

More information:
Oscillating flower colour changes of Causonis japonica (Thunb.) Raf. (Vitaceae) linked to sexual phase changes, Scientific Reports (2022). DOI: 10.1038/s41598-022-24252-z

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Researchers report finding first bidirectional color-changing flower variety (2022, December 1)
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Lost medieval chapel sheds light on royal burials at Westminster Abbey, finds new study on 15th-century reconstruction

Lost medieval chapel sheds light on royal burials at Westminster Abbey, finds new study featuring 15th-century reconstruction
How the east end of the Abbey church and its furnishes may have looked – crafted by illustrator Stephen Conlin, based on evidence from the study. Credit: Stephen Conlin

New evidence, helping to form a 15th-century reconstruction of part of Westminster Abbey, demonstrates how a section of the building was once the focus for the royal family’s devotion to the cult of a disemboweled saint and likely contained gruesome images of his martyrdom.

Findings, published in the Journal of the British Archaeological Association, reveal a story of how England’s “White Queen” Elizabeth Woodville once worshiped at the Chapel of St. Erasmus, which may have even featured a whole, single tooth as part of the relics.

Today, only an intricate frame remains from the lost of St. Erasmus. It was demolished in 1502 and little has been known about its role historically.

However, an extensive analysis of all available evidence to date, including a newly-discovered, centuries-old royal grant by the Abbey’s archivist Matthew Payne, and John Goodall, a member of the Westminster Abbey Fabric Advisory Commission, reveal the chapel’s wider importance.

Evidence from the study has also helped to create a visual 15th-century reconstruction of the east end of the Abbey church and its furnishings, crafted by illustrator Stephen Conlin.

Commenting on the prominence of the chapel, Payne says. “The White Queen wished to worship there—and it appears—also to be buried there, as the grant declares prayers should be sung ‘around the tomb of our consort (Elizabeth Woodville).’ The construction, purpose and fate of the St. Erasmus chapel, therefore, deserves more recognition.”

Goodall adds, “Very little attention has been paid to this short-lived chapel. It receives only passing mention in abbey histories, despite the survival of elements of the reredos. The quality of workmanship on this survival suggestions that investigation of the original chapel is long overdue.”

The interment in the chapel of eight-year-old Anne Mowbray, child bride of Elizabeth’s son Richard, Duke of York, also confirms its role as a royal burial site, their study finds.

In the end, Elizabeth’s last resting place was next to her beloved husband in Windsor in St. George’s Chapel, which Edward IV had begun in 1475. Future monarchs have also been buried in St. George’s, including Elizabeth II after her funeral this year at the Abbey.

St. Erasmus was responsible for child well-being as well as being the patron saint of sailors and abdominal pain. The authors suggest his link with children may have prompted the building of the St. Erasmus chapel. It followed the wedding a year earlier, in 1478, of Anne Mowbray to Richard, when both were still infants.

Dedication of the chapel to St. Erasmus “reflects a new and rapidly growing devotion” to his cult, say the authors. They speculate that the building may also have held relics of the Italian bishop, namely his tooth, which Westminster Abbey is known to have owned.

Although the precise location is unknown, the chapel was almost certainly built on space formerly allotted to a garden and near stalls where William Caxton sold his wares, according to the authors.

Commissioned by Elizabeth, Edward IV’s commoner wife and Henry VIII’s grandmother, St. Erasmus’s chapel was demolished in 1502. Visitors to Westminster Abbey can still view what remains, by looking above the entrance to the chapel of Our Lady of the Pew in the north ambulatory. What does remain is an intricately carved frame, sculpted out of the mineral alabaster. This frame would have surrounded a reredos, which is the imagery that forms the backdrop to the altar.

Missing, however, is the image. The study speculates that this was probably of the Saint being disemboweled—tied down alive to a table while his intestines were wound out on a windlass, a rotating cylinder often used on ships.

The screen would have originally been positioned behind the altar of the St. Erasmus chapel and contained a panel.

The study presents further evidence that the reredos was created by an outsider to the Abbey’s design tradition. Architect Robert Stowell, the Abbey’s master mason, probably designed the chapel itself and may have helped salvage the chapel’s most ornate pieces when it was knocked down after less than 25 years.

This was on Henry VII’s orders to make way for his own and his wife’s chantry and burial place. The Lady Chapel that replaced it features a statue of St. Erasmus, which the authors say may be a nod to Elizabeth Woodville’s now long-forgotten chapel.

More information:
Elizabeth Woodville and the Chapel of St Erasmus at Westminster Abbey, Journal of the British Archaeological Association (2022). DOI: 10.1080/00681288.2022.2101237

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Ageism, sexism and racism still rife in labor market, study finds

job application
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Discrimination against older job applicants is compounded by gender and race, according to a new study showing that ageism is still rife in the U.K. labor market.

The research, carried out by Anglia Ruskin University (ARU) and published in the journal Employee Relations, involved four simultaneous experiments where online job applications from fictitious candidates were made for real U.K. job vacancies in sales, restaurants and cafes.

In the first experiment, the research team sent pairs of matched applications from the control, a fictitious 28-year-old white British male, and from a fictitious 50-year-old white British male (experiment one).

The second experiment paired them with a 50-year-old white British female, the third with a 50-year-old black British male, and the fourth experiment with a 50-year-old black British female.

There were 190 pairs of matched applications in experiment one, 221 pairs in experiment two, 184 pairs in experiment three and 209 pairs in experiment four.

The applications consisted of an email complete with the attachment of an application letter and a CV. All CVs contained information about applicants’ demographic characteristics and work experience. They included the applicants’ year of birth, gender, ethnicity, (married, one child), closely matched previous employment and education (in each experiment, both applicants had completed school to Year 11), hobbies (sports and cinema) and contact information.

In all experiments, the younger white British male was significantly more likely to be offered a —16% more likely than the 50-year-old white British male; 18% more likely than the 50-year-old white British female; 22% more likely than the 50-year-old black British male; and 29% more likely than the 50-year-old black British female.

In addition, the younger white British male candidate was offered interviews for jobs that had a higher average annual salary compared to all other demographics in the experiments. Older white British males were offered interviews for jobs with an annual salary on average 11.5% lower than the 28-year-old white British male. This figure was 12% lower for older white British females and 13% lower for older black British males, while older black British females received offers of interviews for jobs where the salary was 15% lower.

The study is the first to compare access to vacancies and wage sorting between older and younger workers, cross-comparing with gender and race.

The study was carried out by Professor Nick Drydakis and Dr. Anna Paraskevopoulou of the Center for Pluralist Economics at Anglia Ruskin University (ARU). Professor Drydakis said, “It is clear that, several years after the introduction of the 2010 Equality Act, age discrimination in the labor market persists. Our research shows this gulf is exacerbated by factors of race and gender.

“These results suggest that might have to spend more time, effort and resources than to obtain an interview for a lower-paid vacancy, despite often having many years of experience in the workplace behind them.

“The U.K. has an aging population and the retirement age is increasing. An active older population enjoying equal treatment in the job market will be better able to contribute to growth and the economy.”

More information:
Nick Drydakis et al, A field study of age discrimination in the workplace: the importance of gender and race‒pay the gap, Employee Relations: The International Journal (2022). DOI: 10.1108/ER-06-2021-0277

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Ageism, sexism and racism still rife in labor market, study finds (2022, November 30)
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Researchers discover new form of antimicrobial resistance

resistant bacteria
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Australian researchers have uncovered a new form of antimicrobial resistance (AMR), undetectable using traditional laboratory testing methods, in a discovery set to challenge existing efforts to monitor and tackle one of the world’s greatest health threats.

AMR is expected to claim 10 million lives a year by 2050, with scientists racing to understand and get ahead of the diminishing benefits of antibiotics.

Now, a team led by Dr. Timothy Barnett, Head of the Strep A Pathogenesis and Diagnostics team at the Wesfarmers Centre of Vaccines and Infectious Diseases, based at Telethon Kids Institute in Perth, Western Australia, has unearthed a critical clue to the way some bacteria are managing to dodge antibiotics—a finding expected to be the tip of the iceberg.

In research published today in Nature Communications, the team revealed a new mechanism that enables bacteria to take up nutrients from their and bypass . The researchers made the discovery while investigating antibiotic susceptibility of group A streptococcus—a potentially deadly bacteria often found in the throat and on the skin.

“Bacteria need to make their own folates to grow, and in turn, cause disease. Some antibiotics work by blocking this folate production to stop bacteria growing and treat the infection,” Dr. Barnett explained.

“When looking at an antibiotic commonly prescribed to treat group A strep skin infections, we found a mechanism of resistance, where for the first time ever, the bacteria demonstrated the ability to take folates directly from its human host when blocked from producing their own. This makes the antibiotic ineffective and the infection would likely worsen when the patient should be getting better.”






“This new form of resistance is undetectable under conditions routinely used in pathology laboratories, making it very hard for clinicians to prescribe antibiotics that will effectively treat the infection, potentially leading to very poor outcomes and even .

“Unfortunately, we suspect this is just the tip of the iceberg—we have identified this mechanism in group A strep but it’s likely it will be a broader issue across other bacterial pathogens,” Dr. Barnett said. The team’s research highlighted that understanding AMR is far more complex than first thought.

“AMR is a silent pandemic of much greater risk to society than COVID-19—in addition to 10 million deaths per year by 2050, the World Health Organization estimates AMR will cost the global economy $100 trillion if we can’t find a way to combat antibiotic failure,” he added. “Without antibiotics, we face a world where there will be no way to stop deadly infections, won’t be able to have chemotherapy and people won’t have access to have life-saving surgeries.

“In order to preserve the long-term efficacy of antibiotics, we need to further identify and understand new mechanisms of antibiotic resistance, which will aid in the discovery of new antibiotics and allow us to monitor AMR as it arises.”

First author Kalindu Rodrigo will now focus on developing testing methods to detect this antibiotic resistance mechanism to enable effective treatment.

“In the context of increasing AMR, it is important to have new diagnostic tools that can rapidly detect , including host-dependent resistance. Therefore, we hope to develop rapid point-of-care tests that can be used in remote settings where group A strep infections are endemic,” Rodrigo said.

“It is vital we stay one step ahead of the challenges of AMR, and as researchers, we should continue to explore how resistance develops in pathogens and design rapid accurate diagnostic methods and therapeutics. On the other hand, equal efforts should be taken at all levels of the society including patients, health professionals and policy makers to help reduce the impacts of AMR,” Rodrigo concluded.

More information:
Host-dependent resistance of Group A Streptococcus to sulfamethoxazolemediated by a horizontally-acquired reduced folate transporter, Nature Communications (2022). DOI: 10.1038/s41467-022-34243-3

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Engineers use quantum computing to develop transparent window coating that blocks heat, saves energy

Engineers use quantum computing to develop transparent window coating that blocks heat, saves energy
Notre Dame’s Golden Dome partially photographed through a sample (top left) of the TRC coating. Credit: University of Notre Dame

Cooling accounts for about 15 percent of global energy consumption. Conventional clear windows allow the sun to heat up interior spaces, which energy-guzzling air-conditioners must then cool down. But what if a window could help cool the room, use no energy and preserve the view?

Tengfei Luo, the Dorini Family Professor of Energy Studies at the University of Notre Dame, and postdoctoral associate Seongmin Kim have devised a transparent coating for windows that does just that.

The coating, or transparent radiative cooler (TRC), allows to come in and keeps other heat-producing light out. The researchers estimate that this invention can reduce electric cooling costs by one-third in hot climates compared to conventional glass windows.

Transparent radiative coolers can be used for buildings and cars to help address climate change challenges. Luo and his team were able to design their best-in-class TRC by using quantum computing combined with machine learning.

The TRC is made up of multiple ultra-thin layers of materials that must be assembled in a precise configuration. By constructing a computational model of the TRC, researchers were able to test each possible configuration of layers in a fraction of a second to identify the optimum combination and order of materials.

Guided by these results, they fabricated the new coating by layering silica, alumina and titanium oxide on a glass base—topping it off with the same polymer used to make contact lenses. The result was a 1.2 micron-thick that outperforms all other heat-reducing glass coatings on the market.

“I think the quantum computing strategy is as important as the material itself,” said Luo. “Using this approach, we were able to find the best-in-class material, design a radiative cooler and experimentally prove its .”

Their research was published in ACS Energy Letters, a journal of the American Chemical Society.

More information:
Seongmin Kim et al, High-Performance Transparent Radiative Cooler Designed by Quantum Computing, ACS Energy Letters (2022). DOI: 10.1021/acsenergylett.2c01969

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Engineers use quantum computing to develop transparent window coating that blocks heat, saves energy (2022, November 29)
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How seasonal job schemes are draining Pacific nations of vital workers

field worker
Credit: Unsplash/CC0 Public Domain

The economic impact of COVID on Pacific Island states, combined with major labor shortages in Australia and New Zealand, has created a perfect storm. A mass exodus means Pacific nations are now losing crucial workers at such volume that their own development prospects are being undermined.

For 15 years we’ve been told Pacific seasonal labor schemes offer a “triple win“—for Pacific people wanting to earn decent incomes, for their home countries’ revenues and skill base, and for Australian and New Zealand horticulturalists desperate for workers.

Recent developments, however, suggest Pacific labor schemes need a major rethink.

Pacific peoples have long moved across oceans and the world in search of opportunities. But in 2007 New Zealand formalized arrangements with its Recognized Seasonal Employment (RSE) scheme. This was followed by two schemes in Australia, which in 2022 were merged to form the Pacific Australia Labor Mobility (PALM) scheme.

Both countries target low- to semi-skilled workers, mainly for seasonal agricultural and horticultural work. The PALM scheme has since expanded to include hospitality, age care and tourism jobs. Predictably, supply has followed demand.

Supply and demand

The COVID-19 pandemic had a devastating effect on Pacific Island economies. For example, more than 100,000 Fijians lost their jobs, and the government lost half its tax revenue. Unsurprisingly, when borders began to open from late 2021, Pacific people queued for employment opportunities abroad.

This coincided with a severe labor shortage in a number of sectors in Australia and New Zealand. The New Zealand fruit industry, for example, didn’t meet forecast revenue and production levels in 2021, leading to an urgent call for new intakes of Pacific workers.

The subsequent rise in the RSE quota—from 14,400 in 2020–21 to 19,000 in 2022–23—has seen more Pacific people than ever leave their own countries to work in New Zealand.

The total number of Samoan workers under the Australian and New Zealand work schemes, for example, doubled from 3,114 in 2019–20 to 6,600 in 2021–22. By this September, there were more than 29,000 PALM workers in Australia, with plans to increase this to 35,000 in 2023.

One-way traffic

The flip side is that Pacific Island businesses are now lamenting the loss of experienced and well-trained workers, especially in tourism. Cook Islands faced an acute loss of employees earlier this year, with 700 job vacancies reported in April.

More recently, 20 teachers from Samoa joined the fleet of 3,000 workers in Australian labor programs. The resulting teacher shortage will be felt most by young people in the small nation. Similarly, Fiji has lost 40 mechanics to Australia’s temporary skilled work visa schemes between 2016 and 2021.

Vanuatu is also experiencing a labor shortage, with business owners saying they train employees only to see them leave for New Zealand and Australia. A shortage in chefs threatens the viability of restaurants, but picking fruit overseas can be more lucrative than working in hospitality at home.

The same is true in Fiji, which has lost hundreds of front-line tourism workers this year—receptionists, managers and waiters, as well as chefs—which may undermine the country’s efforts to rebuild its tourism industry.

These statistics challenge claims by the Australian Department of Foreign Affairs that jobs programs provide a “skills dividend to Pacific countries.”

Exploitation and poor conditions

The problem is part of a wider concern over Pacific labor schemes. For years, questions have been asked about whether such schemes truly live up to their aim of providing low-skilled workers with training and development opportunities as well as income.

As various commentators have noted, migrant work can have real implications for well-being due to long periods of separation from families, as well as mental and physical burnout.

With so many Pacific workers now overseas for long periods, these problems can have longer-term social costs. Recent research has detailed extramarital affairs, relationship breakdowns, , parenting problems, and child welfare issues.

And while Pacific workers can undoubtedly benefit from seasonal employment overseas, there have been serious allegations in New Zealand this year about unacceptable working and living conditions. As one analysis put it, “Vulnerable workers are at risk of exploitation, underpay, and modern slavery conditions.”

Vanuatu’s government launched an enquiry after widespread complaints about treatment of its workers in Australia. Meanwhile, the Samoan government went so far as to temporarily stop seasonal worker flights after concerns were raised about the well-being and treatment of workers in Australia.

Improvement at home

While ensuring workers are properly taken care of under the PALM and RSE schemes, Pacific governments also need to look inwards. Their citizens will continue to seek opportunities abroad if they don’t feel they get a fair deal in their own labor markets.

RSE scheme workers are entitled to New Zealand’s minimum hourly wage of NZ$22.10. By comparison, Pacific wages are shockingly low. After a decade’s stagnation, for instance, Fiji has begun an incremental minimum wage increase—but this will only see the hourly rate rise from FJD$2.68 (NZ$1.96) to FJD$4.00 (NZ$2.92) in 2023.

As well, there are serious concerns about work conditions and employment rights in some countries. Recently, the Fiji Trade Union Congress was denied the right to protest for the fifth time.

These issues—on top of ongoing uncertainty around post-pandemic job security—will have to be addressed if the current cycle of richer economies siphoning off vulnerable workers from the Pacific is to be broken.

Better job opportunities and pathways in Pacific nations are not only vital to their economies, they’re also integral to the development of industries that will be resilient and sustainable in the future.

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Explainable AI-based physical theory for advanced materials design

Explainable AI-based physical theory for advanced materials design
An image depicting the extended Landau free energy model developed by a research team from Tokyo University of Science, which enables a causal analysis of the magnetization reversal in nanomagnets. Through this model, the team could visualize magnetic domain images effectively and were successful in the inverse designing of nanostructures with low energy requirements. Credit: Kotsugi Laboratory from Tokyo University of Science, Japan.

Microscopic materials analysis is essential to achieve desirable performance in next-generation nanoelectronic devices, such as low power consumption and high speeds. However, the magnetic materials involved in such devices often exhibit incredibly complex interactions between nanostructures and magnetic domains. This, in turn, makes functional design challenging.

Traditionally, researchers have performed a visual analysis of the microscopic image data. However, this often makes the interpretation of such data qualitative and highly subjective. What is lacking is a causal analysis of the mechanisms underlying the in nanoscale .

In a recent breakthrough published in Scientific Reports, a team of researchers led by Prof. Masato Kotsugi from Tokyo University of Science, Japan succeeded in automating the interpretation of the microscopic image data. They achieved this using an “extended Landau free energy model” that they developed using a combination of topology, , and free energy.

The model illustrated the physical mechanism as well as the critical location of the magnetic effect, and proposed an optimal structure for a nanodevice. The model used physics-based features to draw energy landscapes in the information space, which could be applied to understand the complex interactions at the nanoscales in a wide variety of materials.

Explainable AI-based physical theory for advanced materials design
Scatterplot of the dimensionality reduction results of principle component analysis. Color represents the total energy. The relationship between magnetic domain and total energy is connected in the explainable feature space. Credit: Masato Kotsugi from Tokyo University of Science, Japan.

“Conventional analysis are based on a visual inspection of microscope images, and the relationships with the material function are expressed only qualitatively, which is a major bottleneck for material design. Our extended Landau free energy model enables us to identify the physical origin and location of the complex phenomena within these materials. This approach overcomes the explainability problem faced by , which in a way amounts to reinventing new physical laws,” Prof. Kotsugi explains.

When designing the model, the team made use of the state-of-art technique in the fields of topology and data science to extend the Landau model. This led to a model that enabled a causal analysis of the magnetization reversal in nanomagnets. The team then carried out an automated identification of the physical origin and visualization of the original magnetic domain images.

Their results indicated that the demagnetization energy near a defect gives rise to a magnetic effect, which is responsible for the “pinning phenomenon.” Further, the team was able to visualize the spatial concentration of energy barriers, a feat that had not been achieved until now. Finally, the team proposed a topologically inverse design of recording devices and nanostructures with .

Explainable AI-based physical theory for advanced materials design
Scientists from TUS have succeeded in visualizing slight changes in microscopic images and understanding the mechanisms that have been difficult to analyze visually. Furthermore, they have succeeded in inverse designing nanostructures with low energy consumption. Credit: Masato Kotsugi from Tokyo University of Science, Japan.

The model proposed in this study is expected to contribute to a wide range of applications in the development of spintronic devices, quantum information technology, and Web 3.

“Our proposed model opens up new possibilities for optimization of magnetic properties for material engineering. The extended method will finally allow us to clarify ‘why’ and ‘where’ the function of a material is expressed. The analysis of material functions, which used to rely on visual inspection, can now be quantified to make precise functional design possible,” concludes Prof. Kotsugi.

More information:
Causal Analysis and Visualization of Magnetization Reversal using Feature Extended Landau Free Energy, Scientific Reports (2022). DOI: 10.1038/s41598-022-21971-1

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Explainable AI-based physical theory for advanced materials design (2022, November 29)
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What ancient underwater food webs can tell us about the future of climate change

marine ecosystem
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What a tangled web we weave. When it comes to the impact of the climate crisis on marine food webs, we apparently have not known the half of it. That’s according to a new University of Nevada, Las Vegas (UNLV) study, which compared ancient and modern ocean ecosystems in a bid to understand how to make them healthier and more resilient.

Some scientists claim that food webs in the oceans have seen very little change over the last 540 million or so years. However, a team of UNLV researchers has revealed that some ancient food webs were actually very different from those of today.

The study, published in the latest edition of the journal Frontiers in Ecology and Evolution, used fossils to rebuild four different from the days when dinosaurs roamed the earth over 65 million years ago. The food webs were also compared to a reconstructed food web from a modern Jamaican reef. The result? The four ancient food webs varied greatly from one another, and the youngest one was not the most similar to today’s Jamaican coral reefs.

Researchers say the findings point to big changes in the structure of marine ecosystems since they first evolved, and that when looking at conservation and restoration plans, damage to these structures over time caused by humans can impact the ability to fix imbalances and ward off extinction of the living within them.

“Learning how work is very important for conservation because it helps scientists predict how ecosystems will respond to ,” said study co-author Carrie Tyler, a marine conservation paleobiologist and assistant professor in the UNLV department of geoscience.

“There is an interconnectedness and dependency between each member, which means when a stressor affects one species, it will ultimately affect the rest of the web,” she said. “If a species is removed from the structure, the function in the food web may no longer be fulfilled because of the missing piece.”

Tyler said this can make it difficult to reintroduce species down the road, as their functions may no longer fit into the structure. “Using paleontology in this way can help us understand what we should be saving and how to save it, giving us another way to look at conservation efforts.”

Added Roxanne Banker, a UNLV postdoctoral researcher working with Tyler, “By studying these structures over time, we can find ways to promote more resilient communities now, and in the future.”

Takeaways

  • Climate change and altered ocean ecosystems due to human activity are of increasing concern. “No pristine ecosystems—those unaltered by human activity—are left on the planet,” Tyler said.
  • Community stability in ocean ecosystem structures is determined by which species are in it, what role they play in moving energy, how those functions interact with each other, and how strongly the animals at the top of the food chain affect the rest of the food web. Researchers are looking at how these systems respond to crises and whether or not the species and functions can survive these stressors.
  • The new UNLV research can help researchers identify long-term effects of biological invasion—such as the introduction of new species and/or predators, as well as other disturbances in the environment—to determine how we can better help ocean ecosystems bounce back from damage.
  • By looking at things over a longer time scale, we can develop a more specific understanding of how has affected , which can help us approach restoration and conservation efforts more effectively.

More information:
Roxanne M. W. Banker et al, Beyond functional diversity: The importance of trophic position to understanding functional processes in community evolution, Frontiers in Ecology and Evolution (2022). DOI: 10.3389/fevo.2022.983374

Citation:
What ancient underwater food webs can tell us about the future of climate change (2022, November 28)
retrieved 28 November 2022
from https://phys.org/news/2022-11-ancient-underwater-food-webs-future.html

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The first SLS launch caused damage to the launch pad. How bad was it?

The First SLS Launch Caused Damage to the Launch Pad. How bad was it?
Launch pad 39B at Kennedy Space Centre, following the launch of Artemis I on November 16. Credit: NASA

When you test launch the most powerful rocket ever successfully flown, there’s bound to be some collateral damage. With 8.8 million pounds of thrust at liftoff, NASA’s Space Launch System (SLS) packs a mighty punch (the Saturn V, which carried astronauts to the moon in 1969, produced 7.5 million pounds). After November 16’s test flight of SLS, dubbed Artemis I, the pad was a little worse for wear, but not outside of expected parameters, NASA officials say.

“The damage that we did see pertain to really just a couple areas on the ‘Zero Deck,'” said Mike Sarafin, Artemis I’s mission manager, at a press conference on November 21, referring to the section of the Mobile Launcher Platform that bears the brunt of the rocket engines at liftoff.

Damage included discoloration and peeling of paint on the pad, two cameras that were rendered inoperable, as well as the destruction of a pair of elevator doors, blown out by the intense pressure at launch. The upper levels of the mobile launcher are currently only accessible by stairs, and the elevators will take several months to repair.

The First SLS Launch Caused Damage to the Launch Pad. How bad was it?
The damaged elevator doors at pad 39B (Kennedy Space Centre). Credit: NASA TV screenshot

While the damage means some expensive repairs are required before a , the pad “will be ready to support Artemis II and we had accounted for that previously in our pre-plan and our budget for the time between Artemis I and II,” Sarafin assured reporters.

There was speculation after the launch that the damage was widespread, mainly because NASA asked journalists not to photograph the launch tower post-launch. NASA cited security violations relating to ITAR (International Traffic in Arms Regulations), claiming that some now exposed umbilical features would present a if shared publicly.

NASA has since been more forthcoming with details of the damage. “We also did have some damage to pneumatic lines associated with gaseous nitrogen and gaseous helium, and that in turn caused the on the pad to show that there were low oxygen readings until we got the leaks in the pneumatic lines isolated,” said Sarafin.






Post launch footage of Pad 39B at Kennedy Space Centre. Credit: NASA

In terms of debris from the rocket itself, two items were found during the pad assessment: throat plug material from the solid rocket boosters, which is purposefully expelled at liftoff, and caulking from the human-rated Orion capsule. It was unclear whether the caulking was removed during the launch, or during Hurricane Nicole, which tore through Kennedy Space Center a week before liftoff.

NASA says that the pad’s ground systems, on the whole, exceeded expectations, and they are confident it will be ready for the next flight (as yet unscheduled), which will be the first SLS to carry humans to lunar orbit.

Meanwhile, the Orion capsule carried aboard Artemis I is mid-mission, having reached its closest approach to the moon already. It will return to Earth on December 11.

Provided by
Universe Today


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The first SLS launch caused damage to the launch pad. How bad was it? (2022, November 28)
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Cracking open a fossil bone reveals rapid juvenile growth in early tetrapods

Cracking open a fossil bone reveals rapid juvenile growth in early tetrapods
A skeletal reconstruction of Whatcheeria deltae (credit B. Otoo). This study made thin-sections of Whatcheeria thigh bones (femora) including a juvenile femur that revealed a type of bone that is associated with elevated growth rates. In histological section and under polarized light, this disorganized tissue in juvenile Whatcheeria femora suggest that this animal grew quickly early in its lifetime. Credit: B. Otoo

The rise of tetrapods (four-limbed vertebrates) is one of the iconic evolutionary transitions preserved in the fossil record. These animals, which lived about 385 to 320 million years ago during the Devonian and Carboniferous periods of Earth’s history, set the stage for the evolution and diversification of all other terrestrial vertebrates as we know them today, including amphibians, reptiles, birds, and mammals like humans.

It was long thought that these early animals grew very slowly throughout their lifetime, gradually getting bigger and bigger, similar to a modern salamander. However, in a new study in Communications Biology researchers in the Department of Organismic and Evolutionary Biology (OEB) at Harvard University, the Committee on Evolutionary Biology (CEB) at the University of Chicago, and the Field Museum of Natural History cracked open the fossil femora (thigh) bone of a range of growth stages in the early tetrapod, Whatcheeria deltae, and found evidence that the animal grew quickly into adulthood, calling into question conventional wisdom on tetrapod growth.

Lead author Megan R. Whitney, former postdoctoral researcher in OEB, and senior author Professor Stephanie E. Pierce (OEB), Curator of Vertebrate Paleontology in the Museum of Comparative Zoology, have been studying early tetrapods to better understand how they grew, which helps to provide more clarity into the life histories of the animals. “Examining these fossils is like reading a storybook and we are trying to read as many chapters as possible by looking at how juveniles grow building up to adulthood,” said Whitney, “because of where Whatcheeria sits in the early tetrapod family tree we wanted to target this animal and look at its storybook at different stages of life.”

The rarity of early tetrapod samples in the is a challenge for scientists who are often working from incomplete fossil bodies or species groups. Whatcheeria, however, is a unique exception because it is represented by hundreds of bones from several individuals of different sizes that were all preserved in one locality in Iowa. “Whatcheeria is one of the stars of our paleontology collection,” said co-author Dr. Ken Angielczyk, MacArthur Curator of Paleomammology at the Field Museum. “It is one of the best represented early tetrapods in the fossil record, and the abundance of material lets us ask questions about its biology that are impossible for nearly all of its contemporaries.”

Cracking open a fossil bone reveals rapid juvenile growth in early tetrapods
The growth of Whatcheeria at four different stages of life were studied by examining the kind of bone present at specimen representatives from each stage. Bone organization can be used as a proxy for growth rate and this study reports disorganized, fibrolamellar bone in juvenile specimens and more organized bone in adult specimens. This pattern of fast rapid growth early in the life of Whatcheeria, followed by slow and reduced growth in the adults is a new finding in early tetrapods. This finding suggests that rather than growing slow-and-steady throughout their lives, at least some early tetrapods were growing rapidly to reach their adult size. Credit: Skeletal reconstruction by B. Otoo.

Whatcheeria resembled an over-sized salamander with robust legs and arms that supported its weight on land, yet had other anatomical features that suggest it was still bound to water. Whatcheeria lived on the margins of a lowland terrestrial lake at the interface of water and land between about 331 and 326 million years ago, suggesting these animals spent time in both aquatic and terrestrial habitats.

Co-author Benjamin K.A. Otoo (CEB) and Angielczyk provided nine representative samples spanning the known size classes of Whatcheeria from juvenile to adult. Whitney and Pierce then made wafer thin slices of the fossil to examine the microscopic structure of the bone tissues in the thigh bones (femora) by placing the wafers under a polarized light microscope. When they cracked open and examined the juvenile bone sample they found evidence of fibrolamellar bone, which is primary bone tissue associated with fast growth.

“I have a very distinct memory of jumping on slack with Stephanie [Pierce] and saying this breaks all of the rules that we thought of for how growth is evolving in these early tetrapods,” said Whitney.

Pierce and Whitney recalled one of their earlier studies on the tetrapod Greererpeton, a slightly younger Carboniferous early , which showed a very different growth strategy of moderate growth with a period of no growth for a long period of time. They hypothesized this could be due to migration of the animal between bodies of water.

Cracking open a fossil bone reveals rapid juvenile growth in early tetrapods
Under polarized light, an image of the fibrolamellar bone described in the youngest specimens sampled in this study. The vascular spaces (porous, purple spaces) and bone tissue (pink) are haphazardly organized suggesting rapid overall growth of the animal. Credit: M. Whitney

“We saw this in multiple individuals of Greererpeton, so when we looked at the bones of Whatcheeria and found something completely different again, we knew these animals and their life histories must be affected by their interactions with their environment and their places in their ancient ecosystems,” said Pierce.

Whatcheeria is one of the largest animals recovered from the fossil site in Iowa. The large size combined with the evidence of fibrolamellar bone led researchers to hypothesize that Whatcheeria may have grown fast to quickly reach the large size necessary to be a top predator in its environment.

“If you’re going to be a top predator, a very large animal, it can be a competitive advantage to get big quickly as it makes it easier to hunt other animals, and harder for other predators to hunt you,” said Pierce. “It can also be a beneficial survival strategy when living in unpredictable environments, such as the lake system Whatcheeria inhabited, which went through seasonal dying periods.”

The assumption has always been that only amniotes (reptiles, birds and mammals) deposited fibrolamellar bone consistent with and that slow growth was ancestral for tetrapods. But as Whitney and Pierce discovered, this bone tissue type evolved close to the origin of the first tetrapods, much earlier than anybody ever expected.

Cracking open a fossil bone reveals rapid juvenile growth in early tetrapods
Under polarized light, an image of the fibrolamellar bone at the outer surface of the femur of the youngest specimens sampled in this study. The vascular spaces (porous, purple spaces) and bone tissue (pink) are haphazardly organized suggesting rapid overall growth of the animal. Credit: M. Whitney

“Whatcheeria’s elevated growth rates as a juvenile shows us that maybe slow and steady growth throughout a lifetime is not actually the ancestral condition for all tetrapods,” said Whitney, “and this finding contributes to the diversity of patterns we see as we continue to sample more and more early tetrapods. We’re seeing they are not all slow, sluggish animals, but are incredibly diverse in their own right.”

Whitney, currently Assistant Professor at Loyola University Chicago, and Pierce plan to continue investigating the bone tissue microstructure of to reveal their life histories and how they relate to their ecological niche, specifically targeting found earlier in the fossil record than Whatcheeria. “We recently gathered histology data on a relative of Whatcheeria using advanced synchrotron technology,” said Pierce, “and our exciting preliminary results point to yet another unexpected growth strategy.”

More information:
Fossil bone histology reveals ancient origins for rapid juvenile growth in tetrapods, Communications Biology (2022). DOI: 10.1038/s42003-022-04079-0

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Harvard University


Citation:
Cracking open a fossil bone reveals rapid juvenile growth in early tetrapods (2022, November 28)
retrieved 28 November 2022
from https://phys.org/news/2022-11-fossil-bone-reveals-rapid-juvenile.html

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