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    Sea urchin skeletons’ splendid patterns may strengthen their structure

    Sea urchin skeletons may owe some of their strength to a common geometric design.

    Components of the skeletons of common sea urchins (Paracentrotus lividus) follow a similar pattern to that found in honeycombs and dragonfly wings, researchers report in the August Journal of the Royal Society Interface. Studying this recurring natural order could inspire the creation of strong yet lightweight new materials.

    Urchin skeletons display “an incredible diversity of structures at the microscale, varying from fully ordered to entirely chaotic,” says marine biologist and biomimetic consultant Valentina Perricone. These structures may help the animals maintain their shape when faced with predator attacks and environmental stresses.

    While using a scanning electron microscope to study urchin skeleton tubercules — sites where the spines attach that withstand strong mechanical forces — Perricone spotted “a curious regularity.” Tubercules seem to follow a type of common natural order called a Voronoi pattern, she and her colleagues found.

    This Voronoi pattern generated on a computer has an 82 percent match with the pattern found in sea urchin skeletons.V. Perricone

    Using math, a Voronoi pattern is created by a process that divides a region into polygon-shaped cells that are built around points within them called seeds (SN: 9/23/18). The cells follow the nearest neighbor rule: Every spot inside a cell is nearer to that cell’s seed than to any other seed. Also, the boundary that separates two cells is equidistant from both their seeds.

    A computer-generated Voronoi pattern had an 82 percent match with the pattern found in sea urchin skeletons. This arrangement, the team suspects, yields a strong yet lightweight skeletal structure. The pattern “can be interpreted as an evolutionary solution” that “optimizes the skeleton,” says Perricone, of the University of Campania “Luigi Vanvitelli” in Aversa, Italy.

    Urchins, dragonflies and bees aren’t the only beneficiaries of Voronoi architecture. “We are developing a library of bioinspired, Voronoi-based structures” that could “serve as lightweight and resistant solutions” for materials design, Perricone says. These, she hopes, could inspire new developments in materials science, aerospace, architecture and construction. More

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    Robotic kidney cancer surgery shows desirable outcomes in study

    Kidney cancer is not always confined to the kidney. In advanced cases, this cancer invades the body’s biggest vein, the inferior vena cava (IVC), which carries blood out of the kidneys back to the heart. Via the IVC, cancer may infiltrate the liver and heart. The Mays Cancer Center at The University of Texas Health Science Center at San Antonio (UT Health San Antonio) is one of the high-volume centers in the U.S. with surgical expertise in treating this serious problem. The Mays Cancer Center is San Antonio’s National Cancer Institute-designated Cancer Center.
    In a study featured on the cover of the Journal of Urology (Official Journal of the American Urological Association), researchers from the Mays Cancer Center and Department of Urology at UT Health San Antonio show that robotic IVC thrombectomy (removal of cancer from the inferior vena cava) is not inferior to standard open IVC thrombectomy and is a highly safe and effective alternative approach. The affected kidney is removed along with the tumor during surgery, which is performed at UT Health San Antonio’s clinical partner, University Hospital.
    Harshit Garg, MD, urologic oncology fellow in the Department of Urology, is first author of the study, and Dharam Kaushik, MD, urologic oncology fellowship program director, is the senior author. Kaushik is an associate professor and the Stanley and Sandra Rosenberg Endowed Chair in Urologic Research at UT Health San Antonio.
    The open surgery requires an incision that begins 2 inches below the ribcage and extends downward on both sides of the ribcage. “It looks like an inverted V,” Kaushik said. Next, organs that surround the IVC, such as the liver, are mobilized, and the IVC is clamped above and below the cancer. In this way, surgeons gain control of the inferior vena cava for cancer resection.
    “Open surgery has an excellent success rate, and most cases are performed in this manner,” Kaushik said. “But now, with the robotic approach, we can achieve similar results with smaller incisions. Therefore, we need to study the implications of utilizing this newer approach.”
    The study is a systematic review and meta-analysis of data from 28 studies that enrolled 1,375 patients at different medical centers. Of these patients, 439 had robotic IVC thrombectomy and 936 had open surgery. Kaushik and his team collaborated with Memorial Sloan Kettering Cancer Center, New York; Cedars-Sinai Medical Center, Los Angeles; and the University of Washington, Seattle, to perform this study.
    “We pulled the data together to make conclusions because, before this, only small studies from single institutions had been conducted to compare the IVC thrombectomy approaches,” Kaushik said.
    Findings
    The results are encouraging and indicate further study of robotic IVC thrombectomy is warranted. The robotic approach in comparison with open was associated with: Fewer blood transfusions: 18% of robotic patients required transfusions compared to 64% of open patients. Fewer complications: 5% of robotic patients experienced complications such as bleeding compared to 36.7% of open thrombectomy patients.These large, technically challenging surgeries last eight to 10 hours and involve a multidisciplinary team of vascular surgeons, cardiac surgeons, transplant surgeons and urologic oncology surgeons, Kaushik said.
    “This study is the largest meta-analysis analyzing the outcomes of robotic versus open IVC thrombectomy,” Kaushik said. “In more than 1,300 patients, we found that overall complications were lower with the robotic approach and the blood transfusion rate was lower with this approach.
    “That tells us there is more room for us to grow and refine this robotic procedure and to offer it to patients who are optimal candidates for it,” Kaushik said. “Optimal candidacy for a robotic surgery should be based on a surgeon’s robotic expertise, the extent and burden of the tumor, and the patient’s comorbid conditions. The open surgical approach remains the gold standard for achieving excellent surgical control.” More

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    Compost to computer: Bio-based materials used to salvage rare earth elements

    What do corncobs and tomato peels have to do with electronics? They both can be used to salvage valuable rare earth elements, like neodymium, from electronic waste. Penn State researchers used micro- and nanoparticles created from the organic materials to capture rare earth elements from aqueous solutions.
    Their findings, available online now, will also be published in the November issue of Chemical Engineering Journal.
    “Waste products like corncobs, wood pulp, cotton and tomato peels often end up in landfills or in compost,” said corresponding author Amir Sheikhi, assistant professor of chemical engineering. “We wanted to transform these waste products into micro- or nanoscale particles capable of extracting rare earth elements from electronic waste.”
    Rare earth metals are used to manufacture strong magnets used in motors for electric and hybrid cars, loudspeakers, headphones, computers, wind turbines, TV screens and more. However, mining these metals proves challenging and environmentally costly, according to Sheikhi, as large land areas are required to mine even small amounts of the metals. Instead, efforts have turned to recycling the metals from electronic waste items like old computers or circuit boards.
    The challenge lies in efficiently separating the metals from refuse, Sheikhi said.
    “Using the organic materials as a platform, we created highly functional micro- and nanoparticles that can attach to metals like neodymium and separate them from the fluid that surrounds them,” Sheikhi said. “Via electrostatic interactions, the negatively-charged micro- and nano-scale materials bind to positively-charged neodymium ions, separating them.”
    To prepare the experiment, Sheikhi’s team ground up tomato peel and corncob and cut wood pulp and cotton paper into small, thin pieces and soaked them in water. Then, they chemically reacted these materials in a controlled fashion to disintegrate them into three distinct fractions of functional materials: microproducts, nanoparticles and solubilized biopolymers. Adding the microproducts or nanoparticles to neodymium solutions triggered the separation process, resulting in the capture of neodymium samples. More

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    Extreme climate shifts long ago may have helped drive reptile evolution

    There’s nothing like a big mass extinction to open up ecological niches and clear out the competition, accelerating evolution for some lucky survivors. Or is there? A new study suggests that the rate of climate change may play just as large a role in speeding up evolution.

    The study focuses on reptile evolution across 57 million years — before, during and after the mass extinction at the end of the Permian Period (SN: 12/6/18). That extinction event, triggered by carbon dioxide pumped into the atmosphere and oceans through increased volcanic activity about 252 million years ago, knocked out a whopping 86 percent of Earth’s species. Yet reptiles recovered from the chaos relatively well. Their exploding diversity of species around that time has been widely regarded as a result of their slithering into newly available niches.

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    But rapid climate fluctuations were already taking place much earlier in the Permian, and so were surges of reptile diversification, researchers say. Analyzing fossils from 125 reptile species shows that bursts of evolutionary diversity in reptiles were tightly correlated with relatively rapid fluctuations in climate throughout the Permian and millions of years into the next geologic period, the Triassic, researchers report August 19 in Science Advances.

    Scientists’ understanding of evolution is expanding as they become more tuned into the connection between it and environmental change, says Jessica Whiteside, a geologist at the University of Southampton in England who works on mass extinctions but was not involved in the new work. “This study is bound to become an important part of that conversation.”

    To investigate reptile evolution, evolutionary paleobiologist Tiago Simões of Harvard University and colleagues precisely measured and scanned reptile fossils ranging from 294 million to 237 million years old. In all, the researchers examined 1,000 specimens at 50 research institutions in 20 countries.  For climate data, the team used an existing large database of sea surface temperatures based on oxygen isotope data, extending back 450 million years, published in 2021.

    By closely tracking changes in body and head size and shape in so many species, paired with that climate data, the researchers found that the faster the rate of climate change, the faster reptiles evolved. The fastest rate of reptile diversification did not occur at the end-Permian extinction, the team found, but several million years later in the Triassic, when climate change was at its most rapid and global temperatures witheringly hot. Ocean surface temperatures during this time soared to 40° Celsius, or 104⁰ Fahrenheit — about the temperature of a hot tub, says Simões.

    A few species did evolve less rapidly than their kin, Simões says. The difference? Size. For instance, reptiles with smaller body sizes are already preadapted to live in rapidly warming climates, he says. Due to their greater surface area to body ratio, “small-bodied reptiles can better exchange heat with their surrounding environment,” so stay relatively cooler than larger animals.

    “The smaller reptiles were basically being forced by natural selection to stay the same, while during that same period of time, the large reptiles were being told by natural selection ‘You need to change right away or you’re going to go extinct,’” Simões says.

    This phenomenon, called the Lilliput effect, is not a new proposal, Simões says, adding that it’s been well established in marine organisms. “But it’s the first time it’s been quantified in limbed vertebrates across this critical period in Earth’s history.”

    Simões and colleagues’ detailed work has refined the complex evolutionary tree for reptiles and their ancestors. But, for now, it’s unclear which played a bigger role in reptile evolution long ago — all those open ecological niches after the end-Permian mass extinction, or the dramatic climate fluctuations outside of the extinction event.

    “We cannot say which one was more important,” Simões says. “Without either one, the course of evolution in the Triassic and the rise of reptiles to global dominance in terrestrial ecosystems would have been quite different.”  More

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    Common, cheap ingredients can break down some ‘forever chemicals’

    There’s a new way to rip apart harmful “forever chemicals,” scientists say.

    Perfluoroalkyl and polyfluoroalkyl substances, also known as PFAS, are found in nonstick pans, water-repellent fabrics and food packaging and they are pervasive throughout the environment. They’re nicknamed forever chemicals for their ability to stick around and not break down. In part, that’s because PFAS have a super strong bond between their carbon and fluorine atoms (SN: 6/4/19). Now, using a bit of heat and two relatively common compounds, researchers have degraded one major type of forever chemical in the lab, the team reports in the Aug. 19 Science. The work could help pave the way for a process for breaking down certain forever chemicals commercially, for instance by treating wastewater.

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    “The fundamental knowledge of how the materials degrade is the single most important thing coming out of this study,” organic chemist William Dichtel said in an August 16 news conference.

    While some scientists have found relatively simple ways of breaking down select PFAS, most degradation methods require harsh, energy-intensive processes using intense pressure — in some cases over 22 megapascals — or extremely high temperatures — sometimes upwards of 1000⁰ Celsius — to break the chemical bonds (SN: 6/3/22).

    Dichtel, of Northwestern University in Evanston, Ill., and his team experimented with two substances found in nearly every chemistry lab cabinet: sodium hydroxide, also known as lye, and a solvent called dimethyl sulfoxide, or DMSO. The team worked specifically with a group of forever chemicals called PFCAs, which contain carboxylic acid and constitute a large percentage of all PFAS. Some of these kinds of forever chemicals are found in water-resistant clothes.

    When the team combined PFCAs with the lye and DMSO at 120⁰ C and with no extra pressure needed, the carboxylic acid fell off the chemical and became carbon dioxide in a process called decarboxylation. What happened next was unexpected, Dichtel said. Loss of the acid led to a process causing “the entire molecule to fall apart in a cascade of complex reactions.” This cascade involved steps that degraded the rest of the chemical into fluoride ions and smaller carbon-containing products, leaving behind virtually no harmful by-products.     .

    “It’s a neat method, it’s different from other ones that have been tried,” says Chris Sales, an environmental engineer at Drexel University in Philadelphia who was not involved in the study. “The biggest question is, how could this be adapted and scaled up?” Northwestern has filed a provisional patent on behalf of the researchers.

    Understanding this mechanism is just one step in undoing forever chemicals, Dichtel’s team said. And more research is needed: There are other classes of PFAS that require their own solutions. This process wouldn’t work to tackle PFAS out in the environment, because it requires a concentrated amount of the chemicals. But it could one day be used in wastewater treatment plants, where the pollutants could be filtered out of the water, concentrated and then broken down. More

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    Building blocks of the future for photovoltaics

    An international research team led by the University of Göttingen has, for the first time, observed the build-up of a physical phenomenon that plays a role in the conversion of sunlight into electrical energy in 2D materials. The scientists succeeded in making quasiparticles — known as dark Moiré interlayer excitons — visible and explaining their formation using quantum mechanics. The researchers show how an experimental technique newly developed in Göttingen, femtosecond photoemission momentum microscopy, provides profound insights at a microscopic level, which will be relevant to the development of future technology. The results were published in Nature.
    Atomically thin structures made of two-dimensional semiconductor materials are promising candidates for future components in electronics, optoelectronics and photovoltaics. Interestingly, the properties of these semiconductors can be controlled in an unusual way: like Lego bricks, the atomically thin layers can be stacked on top of each other. However, there is another important trick: while Lego bricks can only be stacked on top — whether directly or twisted at an angle of 90 degrees — the angle of rotation in the structure of the semiconductors can be varied. It is precisely this angle of rotation that is interesting for the production of new types of solar cells.
    However, although changing this angle can reveal breakthroughs for new technologies, it also leads to experimental challenges. In fact, typical experimental approaches have only indirect access to the moiré interlayer excitons, therefore, these excitons are commonly termed “dark” excitons. “With the help of femtosecond photoemission momentum microscopy, we actually managed to make these dark excitons visible,” explains Dr. Marcel Reutzel, junior research group leader at the Faculty of Physics at Göttingen University. “This allows us to measure how the excitons are formed at a time scale of a millionth of a millionth of a millisecond. We can describe the dynamics of the formation of these excitons using quantum mechanical theory developed by Professor Ermin Malic’s research group at Marburg.”
    “These results not only give us a fundamental insight into the formation of dark Moiré interlayer excitons, but also open up a completely new perspective to enable scientists to study the optoelectronic properties of new and fascinating materials,” says Professor Stefan Mathias, head of the study at Göttingen University’s Faculty of Physics. “This experiment is ground-breaking because, for the first time, we have detected the signature of the Moiré potential imprinted on the exciton, that is, the impact of the combined properties of the two twisted semiconductor layers. In the future, we will study this specific effect further to learn more about the properties of the resulting materials.”
    This research was made possible thanks to the German Research Foundation (DFG) who provided Collaborative Research Centre funding for the CRCs “Control of Energy Conversion on Atomic Scales” and “Mathematics of Experiment” in Göttingen, and the CRC “Structure and Dynamics of Internal Interfaces” in Marburg.
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    No one-size-fits-all artificial intelligence approach works for prevention, diagnosis or treatment using precision medicine

    A Rutgers analysis of dozens of artificial intelligence (AI) software programs used in precision, or personalized, medicine to prevent, diagnose and treat disease found that no program exists that can be used for all treatments.
    “Precision medicine is one of the most trending subjects in basic and medical science today,” said Zeeshan Ahmed, an assistant professor of medicine at Rutgers Robert Wood Johnson Medical School who led the study, published in Briefings in Bioinformatics. “Major reasons include its potential to provide predictive diagnostics and personalized treatment to variable known and rare disorders. However, until now, there has been very little effort exerted in organizing and understanding the many computing approaches to this field. We want to pave the way for a new data-centric era of discovery in health care.”
    Precision medicine, a technology still in its infancy, is an approach to treatment that uses information about an individual’s medical history and genetic profile and relates it to the information of many others to find patterns that can help prevent, diagnose or treat a disease. The AI-based approach rests on a high level of both computing power and machine-learning intelligence because of the enormous scope of medical and genetic information scoured and analyzed for patterns.
    The comparative and systematic review, believed by the authors to be one of the first of its kind, identified 32 of the most prevalent precision medicine AI approaches used to study preventive treatments for a range of diseases, including obesity, Alzheimer’s, inflammatory bowel disease, breast cancer and major depressive disorder. The bevy of AI approaches analyzed in the study — the researchers combed through five years of high-quality medical literature — suggest the field is advancing rapidly but is suffering from disorganization, Ahmed said.
    In AI, software programs simulate human intelligence processes. In machine learning, a subcategory of AI, programs are designed to “learn” as they process more and more data, becoming ever more accurate at predicting outcomes. The effort rests on algorithms, step-by-step procedures for solving a problem or performing a computation.
    Researchers such as Ahmed, who conducts studies on cardiovascular genomics at the Rutgers Institute for Health, Health Care Policy and Aging Research (IFH), are racing to collect and analyze complex biological data while also developing the computational systems that undergird the endeavor.
    Because the use of genetics is “arguably the most data-rich and complex component of precision medicine,” Ahmed said, the team focused especially on reviewing and comparing scientific objectives, methodologies, data sources, ethics and gaps in approaches used.
    Those interested in precision medicine, he said, can look to the paper for guidance as to which AI programs may be best suited for their research.
    To aid the advent of precision medicine, the study concluded that the scientific community needs to embrace several “grand challenges,” from addressing general issues such as improved data standardization and enhanced protection of personal identifying information to more technical issues such as correcting for errors in genomic and clinical data.
    “AI has the potential to play a vital role to achieve significant improvements in providing better individualized and population healthcare at lower costs,” Ahmed said. “We need to strive to address possible challenges that continue to slow the advancements of this breakthrough treatment approach.”
    Other Rutgers researchers involved in the study included Sreya Vadapalli and Habiba Abdelhalim, research assistants at the IFH, and Saman Zeeshan, a bioinformatics research scientist and former postdoctoral research associate at the Rutgers Cancer Institute of New Jersey.
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    Physics of high-temperature superconductors untangled

    When some materials are cooled to a certain temperature, they lose electric resistance, becoming superconductors.
    In this state, an electric charge can course through the material indefinitely, making superconductors a valuable resource for transmitting high volumes of electricity and other applications. Superconductors ferry electricity between Long Island and Manhattan. They’re used in medical imaging devices such as MRI machines, in particle accelerators and in magnets such as those used in maglev trains. Even unexpected materials, such as certain ceramic materials, can become superconductors when cooled sufficiently.
    But scientists previously have not understood what occurs in a material to make it a superconductor. Specifically, how high-temperature superconductivity, which occurs in some copper-oxide materials, works hasn’t been previously understood. A 1966 theory examining a different type of superconductors posited that electrons which spin in opposite directions bind together to form what’s called a Cooper pair and allow electric current to pass through the material freely.
    A pair of University of Michigan-led studies examined how superconductivity works, and found, in the first paper, that about 50% of superconductivity can be attributed to the 1966 theory — but the reality, examined in the second paper, is a bit more complicated. The studies, led by recent U-M doctoral graduate Xinyang Dong and U-M physicist Emanuel Gull, are published in Nature Physics and the Proceedings of the National Academy of Science.
    Electrons floating in a crystal need something to bind them together, Gull said. Once you have two electrons bound together, they build a superconducting state. But what ties these electrons together? Electrons typically repel each other, but the 1966 theory suggested that in a crystal with strong quantum effects, the electron-electron repulsion is being screened, or absorbed, by the crystals.
    While the electron repulsion is absorbed by the crystal, an opposite attraction emerges from the spinning properties of the electrons — and causes the electrons to bind in Cooper pairs. This underlies the lack of electronic resistivity. However, the theory doesn’t account for complex quantum effects in these crystals. More