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)
Monday, November 25, 2024
New theory reveals the shape of a single photon
University of Birmingham
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A new theory, that explains how light and matter interact at the quantum level has enabled researchers to define for the first time the precise shape of a single photon.
A new theory, that explains how light and matter interact at the quantum level has enabled researchers to define for the first time the precise shape of a single photon.
Research at the University of Birmingham, published in Physical Review Letters, explores the nature of photons (individual particles of light) in unprecedented detail to show how they are emitted by atoms or molecules and shaped by their environment.
The nature of this interaction leads to infinite possibilities for light to exist and propagate, or travel, through its surrounding environment. This limitless possibility, however, makes the interactions exceptionally hard to model, and is a challenge that quantum physicists have been working to address for several decades.
By grouping these possibilities into distinct sets, the Birmingham team were able to produce a model that describes not only the interactions between the photon and the emitter, but also how the energy from that interaction travels into the distant ‘far field’.
At the same time, they were able to use their calculations to produce a visualisation of the photon itself.
First author Dr Benjamin Yuen, in the University’s School of Physics, explained: “Our calculations enabled us to convert a seemingly insolvable problem into something that can be computed. And, almost as a bi-product of the model, we were able to produce this image of a photon, something that hasn’t been seen before in physics.”
The work is important because it opens up new avenues of research for quantum physicists and material science. By being able to precisely define how a photon interacts with matter and with other elements of its environment, scientists can design new nanophotonic technologies that could change the way we communicate securely, detect pathogens, or control chemical reactions at a molecular level for example.
Co-author, Professor Angela Demetriadou, also at the University of Birmingham, said: “The geometry and optical properties of the environment has profound consequences for how photons are emitted, including defining the photons shape, colour, and even how likely it is to exist.”
Dr Benjamin Yuen, added: “This work helps us to increase our understanding of the energy exchange between light and matter, and secondly to better understand how light radiates into its nearby and distant surroundings. Lots of this information had previously been thought of as just ‘noise’ - but there’s so much information within it that we can now make sense of, and make use of. By understanding this, we set the foundations to be able to engineer light-matter interactions for future applications, such as better sensors, improved photovoltaic energy cells, or quantum computing.”
Exact Quantum Electrodynamics of Radiative Photonic Environments
The unsolved mystery sounds of the Southern Ocean #ASA187
Quack-like sounds off the coast of New Zealand in the ’80s may have been a conversation.
Acoustical Society of America
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Looking from the stern of the ship as it tows the long horizontal array of hydrophones. The tow cable can be seen going through the metal horn at the stern. The hydrophone array is several hundred meters behind the ship and about 200 meters deep.
MELVILLE, N.Y., Nov. 21, 2024 – Mysterious, repeating sounds from the depths of the ocean can be terrifying to some, but in the 1980s, they presented a unique look at an underwater soundscape.
In July 1982, researchers in New Zealand recorded unidentifiable sounds as a part of an experiment to characterize the soundscape of the South Fiji Basin. The sound consisted of four short bursts resembling a quack, which inspired the name of the sound “Bio-Duck.”
“The sound was so repeatable, we couldn’t believe at first that it was biological,” said researcher Ross Chapman from the University of Victoria. “But in talking to other colleagues in Australia about the data, we discovered that a similar sound was heard quite often in other regions around New Zealand and Australia.”
They came to a consensus that the sounds had to be biological.
Chapman will present his work analyzing the mystery sounds Thursday, Nov. 21, at 10:05 a.m. ET as part of the virtual 187th Meeting of the Acoustical Society of America, running Nov. 18-22, 2024.
“I became involved in the analysis of the data from the experiment in 1986,” Chapman said. “We discovered that the data contained a gold mine of new information about many kinds of sound in the ocean, including sounds from marine mammals.”
“You have to understand that this type of study of ocean noise was in its infancy in those days. As it turned out, we learned something new about sound in the ocean every day as we looked further into the data—it was really an exciting time for us,” he said.
However, the sounds have never been conclusively identified. There are theories the sounds were made by Antarctic Minke whales, since the sounds were also recorded in Antarctic waters in later years, but there was no independent evidence from visual sightings of the whales making the sounds in the New Zealand data.
No matter the animal, Chapman believes that the sounds could be a conversation. The data was recorded by an acoustic antenna, an array of hydrophones that was towed behind a ship. The uniqueness of the antenna allowed the researchers to identify the direction the sounds were coming from.
“We discovered that there were usually several different speakers at different places in the ocean, and all of them making these sounds,” Chapman said. “The most amazing thing was that when one speaker was talking, the others were quiet, as though they were listening. Then the first speaker would stop talking and listen to responses from others.”
He will present the waveform and spectrum of the recordings during his session, as well as further evidence that the work was a conversation between multiple animals.
“It’s always been an unanswered issue in my mind,” Chapman said. “Maybe they were talking about dinner, maybe it was parents talking to children, or maybe they were simply commenting on that crazy ship that kept going back and forth towing that long string behind it.”
Do pipe organs create an auto-tune effect? #ASA187
Pipe organs create sympathetic resonance in concert halls and church sanctuaries
Acoustical Society of America
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Ashley Snow studied the resonant effects of the D-K Organ on concert hall acoustics at Coe College in Cedar Rapids, Iowa.
MELVILLE, N.Y., Nov. 20, 2024 – The pipe organ, with its strong timber base and towering metal pipes, stands as a bastion in concert halls and church sanctuaries. Even when not in use, the pipe organ affects the acoustical environment around it.
Researcher Ashley Snow from the University of Washington sought to understand what effects the world’s largest class of musical instrument has on the acoustics of concert halls that house them.
“The question is how much the pipe organ contributes to an acoustic environment—and the bigger question is, what portion of music is the acoustic environment, and vice versa?” Snow said.
Snow will present data on the sympathetic resonance of pipe organs and its effect on concert hall acoustics on Wednesday, Nov. 20, at 11:00 a.m. ET as part of the virtual 187th Meeting of the Acoustical Society of America, running Nov. 18-22, 2024.
Snow hypothesized that the pipe organ creates an auto-tune effect since its pipes sympathetically resonate to the same frequencies they are tuned to. This effect may enhance the overall musical sound of ensembles that play in concert halls with organs.
A sine-sweep—a resonance test in which a sine-wave shaped signal is used to excite a system—was played through loudspeakers facing the organ pipes and measuring the response with a microphone at different positions. Data was gathered by placing microphones inside and around the organ pipes during a musical performance and a church service.
“I was way up in the ranks dangling a probe microphone into the pipes, trying my hardest not to make a sound or fall,” Snow said.
Snow verified experimentally that sympathetic resonance does occur in organ pipes during musical performances, speeches, and noises at frequencies that align with musical notes, and that the overall amplitude increases when the signal matches the resonance of one or more pipes.
Investigation into the significance of these effects on the overall quality of musical performance to listeners in the audience is still ongoing. Snow hopes to expand this research by comparing room acoustics between rooms with and without the presence of an organ, along with categorizing and mathematically modeling the tuning system of various world instruments. “What about the sympathy of a marimba, cymbal, or piano strings? Or the mode-locking of horns in a band? Would it sound the same if these things were separated from each other? For better or for worse? I want people to think about that.”
Compared to children, adults don’t play as much, but social play into adulthood is considered a universal human trait. Play has a role in building tolerance, cohesion, bonding, and cooperation. By comparison, play in adults of other species has been considered rare, and yet a new study reported in the Cell Press journal Current Biology on November 21 shows that some chimpanzees, like people, continue to play often throughout their entire lives and especially before engaging in acts that require collective cooperation.
“We show that adult social play in chimpanzees can foster a range of cooperative behaviors, from dyadic interactions to complex, risky activities requiring the coordination of multiple individuals,” says Liran Samuni of the German Primate Center in Göttingen, Germany, and the Taï Chimpanzee Project in Côte d’Ivoire. “We have identified a strong link between this positive social behavior, known to elicit joyous emotions, and some of the more intricate forms of cooperation seen in non-human species.”
Samuni and her colleagues have been studying three cohesive groups of chimpanzees living in the Taï Forest of Côte d’Ivoire. While earlier studies of play in wild adult chimpanzees had been lacking, they recognized that adult males and females in these groups play together regularly. Their play often involves physical actions like wrestling, mock biting, slapping, pulling, and chasing. The positive nature of these interactions is emphasized through “play faces” and panting vocalizations, which the researchers liken to human smiles and laughter.
“Though adult-adult social play was not a daily occurrence, it consistently emerged under specific conditions,” Samuni says.
To understand better how play functions in chimpanzee society, they studied the play of 57 adult chimpanzees. The researchers found that adult chimpanzees were more likely to engage in social play before participating in group activities, such as monkey hunting or territorial defense against hostile outsiders. Those who played together were more likely to collaborate in these endeavors, indicating that play can signal cooperative motivation and enhance collective cooperation.
When chimpanzees played with only one other individual, it often involved close social partners, illustrating the strong connection between play, familiarity, and trust. Play also happened more often during times of increased social tension, such as during competition for mates or following recent disputes, suggesting to the researchers that play might offer a means to relieve tension and resolve conflicts.
The findings in the chimpanzees under study may or may not reflect play in other populations of chimpanzees. Samuni explains that’s because chimpanzees are behaviorally diverse and flexible, with different populations displaying unique strategies and behaviors. The prevalence of adult play in this especially cohesive population may strengthen the notion that “societies characterized by cohesion and tolerance also exhibit higher frequencies of adult play,” Samuni says.
In future work, they’d like to learn more about how play in the Taï Forest chimpanzees compares to that in other chimpanzee groups. They also are curious to know whether chimpanzees consciously decide to play as an intentional strategy to foster engagement or if the positive effects of play naturally promote cooperation without the chimpanzees meaning to do so.
Current Biology (@CurrentBiology), published by Cell Press, is a bimonthly journal that features papers across all areas of biology. Current Biology strives to foster communication across fields of biology, both by publishing important findings of general interest and through highly accessible front matter for non-specialists. Visit http://www.cell.com/current-biology. To receive Cell Press media alerts, contact press@cell.com.
Jun 6, 2023—Homo Ludens : a study of the play element in culture. by: Huizinga ... PDF download · download 1 file · SINGLE PAGE ORIGINAL JP2 TAR download.
New method reveals DNA methylation in ancient tissues, unlocking secrets of human evolution
The Hebrew University of Jerusalem
This research introduces a novel method for inferring DNA methylation patterns in non-skeletal tissues from ancient specimens, providing new insights into human evolution. As DNA methylation is a key marker of gene expression, this work allows scientists to explore changes in gene activity in the brain and other tissues that are typically absent from the fossil record. The team applied their method to the brain, offering a deeper understanding of the evolutionary processes that shaped human brain and neural functions. The findings could transform how we study the evolution of human complex traits.
Led by PhD student Yoav Mathov under the guidance of Prof. Liran Carmel and Prof. Eran Meshorer at the Department of Genetics, Institute of Life Sciences and the Edmond & Lily Safra Center for Brain Sciences (ELSC), this research, published in Nature Ecology & Evolution, reveals a way to identify changes in DNA methylation patterns of non-skeletal tissue using ancient DNA sequences.
Unlike previous studies that focused on skeletal tissue—usually the only source of ancient human DNA—this new approach utilizes developmental patterns of DNA methylation to infer skeletal changes in DNA methylation that would be also observed in other tissues. By training an algorithm on methylation data from living species, the team achieved up to 92% precision in predicting DNA methylation across various tissues.
Their algorithm was then applied to ancient humans, revealing over 1,850 sites of differential methylation specifically in prefrontal cortex neurons. Many of these sites are linked to genes crucial for brain development, including the neuroblastoma breakpoint family (NBPF), which has long been associated with human brain evolution.
“The ability to analyze ancient DNA methylation patterns beyond bones gives us a window into how tissues, especially brain cells, have evolved epigenetically over time,” said Mathov. “This could lead to a deeper understanding of the evolutionary forces that shaped the human brain and other vital organs.”
This innovative tool expands the horizons of evolutionary biology and anthropology, allowing scientists to investigate tissue-specific epigenetic changes that are not preserved in fossils. The study paves the way for new insights into the role of epigenetic changes in human evolution and the development of complex neural functions.
Inferring DNA methylation in non-skeletal tissues of ancient specimens
Article Publication Date
20-Nov-2024
Real-world chemists are more diverse than generative AI images suggest
American Chemical Society
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None of the individual AI image generators tested produced a group of images representing the real diversity among chemists, but the entire collection does a better job.
Credit: Adapted from the Journal of Chemical Education 2024, DOI: 10.1021/acs.jchemed.4c00249
Asking children “What does a scientist look like?” now results in more illustrations of women and people of color than decades ago. But do generative artificial intelligence (AI) tools also depict the diversity among scientists? Researchers reporting in the Journal of Chemical Education prompted AI image generators for portraits of chemists. They found that none of the collections accurately represents the gender, racial or disability diversity among real chemists today.
Millions of images are being created by generative AI each day. And the output of these tools is only as good as their algorithms and the initial images used to train the large language models. Recently, researchers have found that AI image generators may produce content that’s not representative of reality — beyond bodily proportions that aren’t close to possible. For example, when a team prompted generative AI tools to produce images of people in various occupations, some perpetuated gender and racial stereotypes rather than reproducing the actual demographics of those workers. So, a team led by Valeria Stepanova, including Meagan Kaufenberg-Lashua, Joseph West and Jaime Kelly, wanted to see how well AI-generated portraits of chemists represent current demographic trends.
The researchers prompted four AI image generators for modern, portrait-style photographs of chemists in industry or academic occupations. Then, with the assistance of undergraduate students, the team assessed the gender and racial distribution as best they could within the 200-image collection. The entire AI collection had a male-female ratio similar to that of the U.S. National Science Foundation’s (NSF) 2021 demographic survey. The researchers also found that most of the generated images were of seemingly White people, which they say is representative of the U.S. chemistry field. But there was considerable variation in the results produced by the individual AI models. One tool generated more females than NSF data says is representative, and another created images only of males. Additionally, two models produced almost no people of color, yet one model generated primarily images of people of color. To the researchers’ surprise, none of the models produced images of chemists with visible disabilities.
Overall, the researchers say that this demonstration illustrates how different image-generating AI can amplify incorrect information about the diversity among chemists. They conclude their study by asking, “Are humans going to control the knowledge generated by AI, or will AI influence the knowledge of generations of people moving forward?”
There was no funding agency for this project.
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The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS’ mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and all its people. The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, e-books and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world’s scientific knowledge. ACS’ main offices are in Washington, D.C., and Columbus, Ohio.
Credit: West Health-Gallup Survey on Mental Health in America, Oct. 1-13, 2024.
WASHINGTON, D.C. — Nov. 21, 2024 — A majority of Americans (70%) say they would prefer to be asked about both their physical and mental health during medical appointments with their primary care providers (PCPs). The finding from the new West Health-Gallup Survey on Mental Health in Americacomes as more than one in five U.S. adults, or 59.3 million people, were living with a mental illness in 2022, and little more than half of them (50.6%) received treatment within the prior year.
According to the survey, majorities of men (65%) and women (76%) are eager to discuss both their mental and physical health with their primary care doctor. Women are 11 percentage points more likely than men to want to talk about both types of health concerns. Additionally, mental health conditions don’t just impact those diagnosed; 53% of Americans in the survey report having someone in their household or a close family member diagnosed with a mental health condition, and nearly 60% say the mental health condition has negatively affected their daily life.
“We can do a better job making the diagnosis and treatment of a mental health condition more accessible, affordable and integrated, and the solution may lie in primary care settings, where patients are most likely to interact with a health professional and less likely to feel stigmatized,” said Tim Lash, president of West Health Policy Center, a nonprofit focused on healthcare and aging. “Patients would benefit from earlier and more proactive management of conditions, and the system would benefit from a more efficient, effective and interconnected approach to care.”
Most Americans (74%) are generally comfortable discussing mental health issues with a primary care provider (41% are “very comfortable” and 33% “somewhat comfortable”). Women and men are equally comfortable, though men are less likely to say they prefer that their doctor ask them about both mental and physical health.
“While it is positive to see the stigma around talking about mental health eroding, America continues to struggle with having enough available primary care providers to have these critical conversations,” said Dan Witters, director of wellbeing research at Gallup. “Many physicians say they are experiencing burnout and are frustrated that they can’t provide the quality of care they want to due to high caseloads.”
“The demand for high-quality care for some of the most common mental health conditions continues to grow,” said Lash. “West Health and collaborators are working on new integrated models now that could be adopted by health systems across the country, which would both increase access and stem the mental health crisis in America. Data show that primary care physicians working in tandem with mental health professionals leads to earlier intervention and better outcomes for patients.”
Methodology The West Health-Gallup Survey on Mental Health in America was conducted by web and mail Oct. 1-13, 2024, with 2,389 adults, aged 18 and older, living in all 50 U.S. states and the District of Columbia as part of the Gallup Panel™.
Gallup delivers analytics and advice to help leaders and organizations solve their most pressing problems. Combining more than 80 years of experience with its global reach, Gallup knows more about the attitudes and behaviors of employees, customers, students and citizens than any other organization in the world.
Effects of livestock-keeping on the transmission of mosquito-borne diseases
Announcing a new article publication for Zoonoses journal. Livestock husbandry provides people with a means of generating revenue and sustenance. However, this activity influences the dispersal of mosquitoes and the diseases that they transmit. Therefore, this study is aimed at examining the effects of livestock husbandry on mosquito population density and the spread of mosquito-borne diseases (MBDs), to raise public awareness of how to protect against MBDs. To accomplish these objectives, relevant material was gathered by searching pertinent databases and extracting relevant data. Overall, it was found that livestock husbandry can have both positive and negative effects on MBD occurrence. Furthermore, cattle husbandry increases mosquito populations, and pigs, horses, dogs, and cats can serve as sentinel animals for arboviruses. Implementing strategies such as administering endectocides to cattle and relocating large animals away from residential areas can safeguard against MBDs. The research suggests that the One Health approach is essential for effectively managing and controlling MBDs. Moreover, offering comprehensive public education regarding potential zoonotic disease hazards associated with livestock husbandry is crucial in both rural and urban areas.
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Zoonoses is fully open access journal for research scientists, physicians, veterinarians, and public health professionals working on diverse disciplinaries of zoonotic diseases. Please visit https://zoonoses-journal.org/ to learn more about the journal.
Emmanuel Ajibola Olagunju, Iyanuoluwa Temitope Ayewumi and Bobola Emmanuel Adeleye. Effects of Livestock-Keeping on the Transmission of Mosquito-Borne Diseases. Zoonoses. 2024. Vol. 4(1). DOI: 10.15212/ZOONOSES-2024-0036
