It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Wednesday, August 02, 2023
New review calls on Hockey Canada to raise age of body contact from 13 to 15
Research from the University of Ottawa’s Faculty of Medicine and CHEO recommends authorities mandate that schools and sports organizations enforce policies to prevent concussions
IMAGE: DR. KRISTIAN GOULET, AN ASSISTANT PROFESSOR IN UOTTAWA’S FACULTY OF MEDICINE AND THE MEDICAL DIRECTOR OF THE CHEO CONCUSSION CLINIC, THE EASTERN ONTARIO CONCUSSION CLINIC, AND THE PEDIATRIC SPORTS MEDICINE CLINIC OF OTTAWA.view more
CREDIT: UNIVERSITY OF OTTAWA
Hockey leagues in Canada should overhaul current rules and regulations to raise the age of bodychecking in the game from 13 to 15, says new research into the effect of body contact on teens.
The literature review was led by Dr. Kristian Gouletnorth_eastexternal link of the University of Ottawa’s Faculty of Medicine and Children’s Hospital of Eastern Ontario (CHEO) and calls on provincial and territorial governments to mandate schools – including those involved with school sports – and sports organizations to establish, update, and enforce policies and protocols to prevent concussion, with a keen focus on body contact.
Currently, hockey organizations in Canada allow body contact in competitive and recreational leagues from the age of 13. But studies have shown when body contact is initiated, injuries increase significantly, including concussion rates.
Almost halfnorth_eastexternal link of hockey injuries are caused by bodychecking, with injury rates four times higher for kids and teens in leagues that allowed bodychecking. Other studiesnorth_eastexternal link have found concussion rates decrease by over 50% when eliminating body contact. An estimated 200,000north_eastexternal link concussions occur annually in Canada, with children and youth affected primarily. Ice hockey is the leading cause of all sports and recreationally related TBI across paediatric age groups, in both boys and girls.
Dr. Goulet is hopeful this review will spur Hockey Canada to lead a new path forward to strengthen our understanding of concussion and guidance for clinical management, especially related to acute care, persistent symptoms, and prevention.
“Sport is incredibly important for the mental physical emotional and social health of our kids. However, it is our duty as healthcare providers, parents, coaches, administrators and decision makers, that we take all reasonable efforts to make sport as safe as possible,” says Dr. Goulet, an Assistant Professor in uOttawa’s Faculty of Medicine and the Medical Director of The CHEO Concussion Clinic, The Eastern Ontario Concussion Clinic, and The Pediatric Sports Medicine Clinic of Ottawa.
IMAGE: NEW ROBOTIC GRIPPERS CAN HANDLE A PLETHORA OF DISPARATE OBJECTS.view more
CREDIT: JIE YIN
Researchers at North Carolina State University have developed a robotic gripping device that is gentle enough to pick up a drop of water, strong enough to pick up a 6.4 kilogram (14.1 pound) weight, dexterous enough to fold a cloth, and precise enough to pick up microfilms that are 20 times thinner than a human hair. In addition to possible manufacturing applications, the researchers also integrated the device with technology that allows the gripper to be controlled by the electrical signals produced by muscles in the forearm, demonstrating its potential for use with robotic prosthetics.
“It is difficult to develop a single, soft gripper that is capable of handling ultrasoft, ultrathin, and heavy objects, due to tradeoffs between strength, precision and gentleness,” says Jie Yin, corresponding author of a paper on the work and an associate professor of mechanical and aerospace engineering at NC State. “Our design achieves an excellent balance of these characteristics.”
The design for the new grippers builds on an earlier generation of flexible, robotic grippers that drew on the art of kirigami, which involves both cutting and folding two-dimensional sheets of material to form three-dimensional shapes.
“Our new grippers also use kirigami, but are substantially different, as we learned a great deal from the previous design,” says Yaoye Hong, co-author of the paper and a recent Ph.D. graduate from NC State. “We’ve been able to improve the fundamental structure itself, as well as the trajectory of the grippers – meaning the path at which the grippers approach an object when grabbing it.”
The new design is able to achieve high degrees of strength and gentleness because of how it distributes force throughout the structure of the gripper.
“The strength of robotic grippers is generally measured in payload-to-weight ratio,” Yin says. “Our grippers weigh 0.4 grams and can lift up to 6.4 kilograms. That’s a payload-to-weight ratio of about 16,000. That is 2.5 times higher than the previous record for payload-to-weight ratio, which was 6,400. Combined with its characteristics of gentleness and precision, the strength of the grippers suggests a wide variety of applications.”
Another benefit of the new technology is that its attractive characteristics are driven primarily by its structural design, rather than by the materials used to fabricate the grippers.
“In practical terms, this means that you could fabricate the grippers out of biodegradable materials, such as sturdy plant leaves,” says Hong. “That could be particularly useful for applications where you would only want to use the grippers for a limited period of time, such as when handling food or biomedical materials. For example, we’ve demonstrated that the grippers can be used to handle sharp medical waste, such as needles.”
The researchers also integrated the gripping device with a myoelectric prosthetic hand, meaning the prosthesis is controlled using muscle activity.
“This gripper provided enhanced function for tasks that are difficult to perform using existing prosthetic devices, such as zipping certain types of zippers, picking up a coin, and so on,” says Helen Huang, co-author of the paper and Jackson Family Distinguished Professor in the Joint Department of Biomedical Engineering at NC State and the University of North Carolina at Chapel Hill.
“The new gripper can’t replace all of the functions of existing prosthetic hands, but it could be used to supplement those other functions,” Huang says. “And one of the advantages of the kirigami grippers is that you would not need to replace or augment the existing motors used in robotic prosthetics. You could simply make use of the existing motor when utilizing the grippers.”
In proof-of-concept testing, the researchers demonstrated that the kirigami grippers could be used in conjunction with the myoelectric prosthesis to turn the pages of a book and pluck grapes off a vine.
“We think the gripper design has potential applications in fields ranging from robotic prosthetics and food processing to pharmaceutical and electronics manufacturing,” Yin says. “We are looking forward to working with industry partners to find ways to put the technology to use.”
The paper, “Angle-programmed tendril-like trajectories enable a multifunctional gripper with ultradelicacy, ultrastrength, and ultraprecision,” is published open access in the journal Nature Communications. The paper was co-authored by Yao Zhao and Yanbin Li, postdoctoral researchers at NC State; Joseph Berman, a Ph.D. student at NC State; and Yinding Chi, a former Ph.D. student at NC State.
The work was done with support from the National Science Foundation under grants 2005374 and 2221479.
-shipman-
CAPTION
Robotic grippers can turn book pages.
CREDIT
Jie Yin
Note to Editors: The study abstract follows.
“Angle-programmed tendril-like trajectories enable a multifunctional gripper with ultradelicacy, ultrastrength, and ultraprecision”
Authors: Yaoye Hong, Yao Zhao, Joseph Berman, Yinding Chi, Yanbin Li and Jie Yin, North Carolina State University; He (Helen) Huang, North Carolina State University and the University of North Carolina at Chapel Hill Published: Aug. 2, 2023, Nature Communications
Abstract: Achieving multicapability in a single soft gripper for handling ultrasoft, ultrathin, and ultraheavy objects is challenging due to the tradeoff between compliance, strength, and precision. Here, combining experiments, theory, and simulation, we report utilizing angle-programmed tendril-like grasping trajectories for an ultragentle yet ultrastrong and ultraprecise gripper. The single gripper can delicately grasp fragile liquids with minimal contact pressure (0.05 kPa), lift objects 16,000 times its own weight, and precisely grasp ultrathin, flexible objects like 4-?m-thick sheets and 2-?m-diameter microfibers on flat surfaces, all with a high success rate. Its scalable and material-independent design allows for biodegradable noninvasive grippers made from natural leaves. Explicitly controlled trajectories facilitate its integration with robotic arms and prostheses for challenging tasks, including picking grapes, opening zippers, folding clothes, and turning pages. This work showcases soft grippers excelling in extreme scenarios with potential applications in agriculture, food processing, prosthesis, biomedicine, minimally invasive surgeries, and deepsea exploration.
‘A place for everything and everything in its place’–making sense of order, or disorder, helps us understand nature. Animals tend to fit nicely into categories: Mammals, birds, reptiles, whatever an axolotl is, and more. Sorting also applies to materials: Insulator, semiconductor, conductor, and even superconductor. Where exactly a material lands in the hierarchy depends on a seemingly invisible interplay of electrons, atoms, and their surroundings.
Unlike animals, the boundaries are less sharp, and tweaking a material’s environment can force it to bounce between categories. For example, dialing down the temperature will turn some materials into superconductors. Snapping on a magnetic field might reverse this effect. Within a single category, different types of order, or phases, can emerge from the sea of particles. Unfortunately, we can’t see this nanoscopic universe with our eyes, but scientists can use advanced imaging tools to visualize what’s going on. Every once in a while, they uncover unexpected and surprising behaviors.
“The discovery of new phases of matter is one of the holy grails in physics and often generates a lot of excitement because it can change our way of thinking and seeing, and even transform how we understand the behavior of quantum particles,” said physics professor Vidya Madhavan.
Led by Madhavan, researchers from the University of Illinois, the University of Maryland, WashU, and the National Institute of Standards and Technology, have now seen unusual waves of charge within a crystal of uranium ditelluride (UTe2). Theorists on the team developed a model that links the experimental observations to a previously unseen facet of the crystal’s unusual superconductivity. The findings, initially shared at a conference last year, inspired other researchers at Cornell University to measure complementary features of the superconductivity directly. Both results were published in the June 28 issue of Nature.
Superconductors were only discovered in the 1900s and scientists are still working to explain the myriad of materials that fall into this category. This work is the latest in a string of results regarding the superconductor UTe2. Researchers from the groups of Nicholas Butch at NIST and Johnpierre Paglione at University of Maryland supplied the crystals for this study. At ambient temperatures, UTe2 is rather unremarkable and resembles a bit of shiny, molten rock. As the material is chilled with liquid helium, it begins to conduct electricity without heating up – this is called superconductivity.
Regular conductivity, the movement of electrons that powers appliances, is mainly a single-particle effect. This means that scientists can explain and predict typical conductivity largely without accounting for the physics of electron-electron interactions. Superconductivity is quite different because it involves electrons interacting to form what are called Cooper pairs.
Pairing is not the same for all materials, and so superconductivity comes in more than one flavor. For example, each electron has a property called spin, which can be oriented in one of two ways: up or down. When two electrons bind together, they can have their spins oriented in opposite directions or in the same direction. This latter one is called triplet pairing and is a rare bird in the world of superconductivity. Over the last few years scientists in this collaboration, as well as in other groups, have made measurements indicating that UTe2 has triplet pairing.
In this study, experimentalists from Madhavan’s group used a scanning tunneling microscope (STM) to visualize the microscopic structure of the material. There are no lenses or mirrors in this microscope. Rather electrons provide a sensitive window into the structure of UTe2. In the microscope, a tungsten tip sweeps across the surface of the material with sub-nanometer resolution. Both the tip and the material are part of an electrical circuit, with electrons scooting through vacuum from tip to material. Quantum tunneling causes this movement and is where the device gets its name. The setup operates at 300 millikelvin and magnetic fields up to around 11 Tesla. The STM revealed that the distribution of electrical charge was not uniform—instead there were stripes.
“We discovered the existence of a charge density wave in the superconducting state, but this by itself is not necessarily unusual. What is strange is that destroying the superconductivity also makes the charge wave goes away,” said Anuva Aishwarya, lead author and a physics graduate student in Madhavan’s group who has been relentlessly chasing down the physics of UTe2 and other exotic materials.
The team did Fourier analysis on the data, which clearly showed charge density waves were present at low magnetic fields, and then vanished above 10 Tesla, where the superconductivity melted away. This was one of the key signals that the waves were somehow intertwined with the material’s superconductivity.
Theorists Julian May-Mann and physics professor Eduardo Fradkin from UIUC provided an explanation for these observations. According to the team, the charge density waves are spawned by an entirely different wave in the material, one that is made up of Cooper pairs. Neither of these waves ebb and flow like water. Instead, they are static variations in two different properties—one relates to the charge and the other to the interacting electron pairs. Together the waves provide insights into the types of order that occur in UTe2. Interwoven parent-daughter waves can also appear in other superconductors that contain copper and oxygen atoms. This new study is the first time that scientists have seen evidence for this in a superconductor with triplet pairing.
“This is very exciting to me. If this charge density wave is originating with a triplet pair density wave then there may be a fundamentally new phase that has come up in this material because of very strong electron interactions,” said Aishwarya.
Paper references: Aishwarya, A., May-Mann, J., Raghavan, A. et al. Magnetic-field-sensitive charge density waves in the superconductor UTe2. Nature 618, 928–933 (2023). https://doi.org/10.1038/s41586-023-06005-8
Magnetic-field-sensitive charge density waves in the superconductor UTe2
Half of popular TikTok videos about Baby Boomers portray older adults negatively, risking reinforcing stereotypes and creating intergenerational conflict
Half of popular TikTok videos about Baby Boomers portray older adults negatively, risking reinforcing stereotypes and creating intergenerational conflict
Article Title: Videos about older adults on TikTok
Author Countries: Singapore
Funding: We gratefully acknowledge the support of the Social Science Research Council SSHR Fellowship (MOE2018-SSHR-004). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Nose-picking healthcare workers were more likely to catch COVID-19 during the pandemic than their colleagues who refrained, per Netherlands cohort study
IMAGE: RELATION BETWEEN NOSE-PICKING AND SARS-COV-2.view more
CREDIT: THIS IMAGE WAS CREATED WITH THE ASSISTANCE OF DALL·E 2 BY OPEN AI. LAVELL ET AL. OWN THE IMAGE, INCLUDING THE RIGHT TO REPRINT, SELL, AND MERCHANDISE (USAGE RIGHTS IN HTTPS://LABS.OPENAI.COM/ABOUT). THE IMAGE IS DISTRIBUTED UNDER THE CC-BY 4.0 LICENSE (HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)
Nose-picking healthcare workers were more likely to catch COVID-19 during the pandemic than their colleagues who refrained, per Netherlands cohort study
Article Title: Why not to pick your nose: Association between nose picking and SARS-CoV-2 incidence, a cohort study in hospital health care workers
Author Countries: The Netherlands
Funding: This work was funded by the Netherlands Organization for Health Research and Development ZonMw (S3 study, grant agreement no. 10430022010023 to M.K.B.) and the Corona Research Fund Amsterdam UMC. The funders were not involved in designing the study, data collection, analysis or interpreting the data, writing the manuscript or the decision to submit the article for publication.
Why not to pick your nose: Association between nose picking and SARS-CoV-2 incidence, a cohort study in hospital health care workers
ARTICLE PUBLICATION DATE
2-Aug-2023
Extreme climates may have driven Middle Pleistocene hominins towards (positive) assortative mating and evolution of bigger brains, according to economic model of climate change impacts
Extreme climates may have driven Middle Pleistocene hominins towards (positive) assortative mating and evolution of bigger brains, according to economic model of climate change impacts
Body adornments are powerful symbols that communicate cultural values and personal identities, and they are therefore highly valuable in the study of ancient cultures. In this study, Alarashi and colleagues analyze materials that adorned the body of an eight-year-old child buried in a grave at the Neolithic village of Ba’ja in Jordan, dating to between 7400 and 6800 BCE.
The materials in question comprise over 2,500 colorful stone and shell, two exceptional amber beads – the oldest known thus far in the Levant – along with a large stone pendant and a delicately engraved mother-of-pearl ring. Analyzing the composition, craftsmanship, and spatial layout of these items, the authors conclude that they belonged to a single composite multi-row necklace that had since fallen apart. As part of this study, the researchers created a physical reconstruction of the original necklace, which is now on display in the Petra Museum in Southern Jordan.
The multi-row necklace is one of the oldest and most impressive Neolithic ornaments, providing new insights into funerary practices at the time for individuals of apparently high social status. The making of the necklace appears to have involved meticulous work, as well as the import of certain exotic materials from other regions. The study of this necklace reveals complex social dynamics between community members at Ba’ja – including artisans, traders, and high-status authorities who would commission such pieces – which certainly merit further investigation of this Neolithic culture.
The authors add: “Adorning the deceased child, bridging the worlds of life and death: The discovery and reconstruction of an extraordinary necklace from the 9000-year-old village of Ba’ja (Jordan).”
Citation: Alarashi H, Benz M, Gresky J, Burkhardt A, Fischer A, Gourichon L, et al. (2023) Threads of memory: Reviving the ornament of a dead child at the Neolithic village of Ba`ja (Jordan). PLoS ONE 18(8): e0288075. https://doi.org/10.1371/journal.pone.0288075
Author Countries: France, Germany, Denmark, Lithuania, Italy, UK, Portugal, Spain
