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)
Tuesday, January 21, 2025
Global public health collaboration benefits Americans, SHEA urges continued support of the World Health Organization (WHO)
The Society for Healthcare Epidemiology of America (SHEA) wants to emphasize the importance of global partnerships in addressing health threats that impact all of us, as Americans and global citizens. We urge President Trump to reconsider the decision to terminate the U.S. relationship with the World Health Organization (WHO). The most effective way to address emerging health threats is through collaborative efforts with international partners. Eliminating U.S. involvement in the WHO would leave our country—and the world—more vulnerable to infectious diseases and less prepared to manage pandemics, fight emerging health threats, respond to chronic diseases, and improve infection prevention resources.
It is essential that the United States continues our connection with the WHO to coordinate surveillance, monitoring, detection, prevention, research, and response to public health threats including outbreaks, antimicrobial resistance and high consequence pathogens such as viral hemorrhagic fevers (Ebola, Marburg), Mpox, and highly pathogenic avian influenza (e.g., H5N1).
SHEA works directly with international organizations, healthcare systems, and experts around the globe to share evidence-based practices, conduct research, and promote innovations in infection prevention. We remain steadfast in our commitment to fostering global partnerships and as such, SHEA will remain involved in the Global Infection Prevention and Control Network (GIPCN) whose mission is to align global efforts on infection prevention, a critical component of fighting chronic diseases and emerging pathogens. Continued partnership with the WHO is also critical to fighting antimicrobial resistance, a serious threat to domestic and global health. We must stay engaged to protect the effectiveness and efficacy of antibiotics. The United States needs to work with other countries to improve the public health of all global citizens, including Americans. SHEA acknowledges the large contributions that the United States makes to support the WHO and encourages the United States to engage in bilateral discussions with the WHO regarding funding and organization rather than complete withdrawal to support these efforts.
Our global collaborations ensure that knowledge and resources transcend borders, benefiting not just healthcare workers and patients in the United States, but also communities worldwide. SHEA remains dedicated to strengthening these relationships to address today’s challenges and prepare for future public health threats.
If this announcement to withdraw from the WHO is implemented, we urge President Trump to reconsider for the health and safety of American citizens and the global community. SHEA will continue to advocate for science-driven, collaborative approaches to protect and improve public health for everyone.
About SHEA
The Society for Healthcare Epidemiology of America (SHEA) works to advance the science and practice of healthcare epidemiology and infection prevention. Founded in 1980, SHEA promotes education, research, and advocacy to improve patient care and safety. For more information, visit www.shea-online.org.
Contact:
Lindsay MacMurray, lmacmurray@shea-online.org
SPACE/COSMOS
Astronomers thought they understood fast radio bursts. A recent one calls that into question.
The new ability to pinpoint sources of fast radio bursts places one recent burst in a surprising location
Astronomer Calvin Leung was excited last summer to crunch data from a newly commissioned radio telescope to precisely pinpoint the origin of repeated bursts of intense radio waves — so-called fast radio bursts (FRBs) — emanating from somewhere in the northern constellation Ursa Minor.
Leung, a Miller Postdoctoral Fellowship recipient at the University of California, Berkeley, hopes eventually to understand the origins of these mysterious bursts and use them as probes to trace the large-scale structure of the universe, a key to its origin and evolution. He had written most of the computer code that allowed him and his colleagues to combine data from several telescopes to triangulate the position of a burst to within a hair's width at arm's length.
The excitement turned to perplexity when his collaborators on the Canadian Hydrogen Intensity Mapping Experiment (CHIME) turned optical telescopes on the spot and discovered that the source was in the distant outskirts of a long-dead elliptical galaxy that by all rights should not contain the kind of star thought to produce these bursts.
Instead of finding an expected "magnetar" — a highly magnetized, spinning neutron star left over from the core collapse of a young, massive star — "now the question was: How are you going to explain the presence of a magnetar inside this old, dead galaxy?" Leung said.
The young stellar remnants that theorists think produce these millisecond bursts of radio waves should have disappeared long ago in the 11.3-billion-year-old galaxy, located 2 billion light years from Earth and weighing more than 100 billion times the mass of the sun.
“This is not only the first FRB to be found outside a dead galaxy, but compared to all other FRBs, it’s also the farthest from the galaxy it’s associated with. The FRB’s location is surprising and raises questions about how such energetic events can occur in regions where no new stars are forming,” said Vishwangi Shah, a doctoral student at McGill University in Montreal, Canada, who refined and extended Leung's initial calculations about the location of the burst, called FRB 20240209A.
Shah is the corresponding author of a study of the FRB published today (Tuesday, Jan. 21) in the Astrophysical Journal Letters along with a second paper by colleagues at Northwestern University in Evanston, Illinois. Leung, a co-author of both papers, is a lead developer of three companion telescopes — so-called outriggers — to the original CHIME radio array located near Penticton, British Columbia. He mentored Shah at McGill while Leung was a doctoral student at the Massachusetts Institute of Technology (MIT) and subsequently held an Einstein Postdoctoral Fellowship at UC Berkeley prior to his Miller fellowship.
New CHIME outrigger in California
A third outrigger radio array will go online this week at Hat Creek Observatory, a facility in Northern California formerly owned and operated by UC Berkeley and now managed by the SETI Institute in Mountain View. Together, the four arrays will immensely improve CHIME's ability to precisely locate FRBs.
"When paired with the three outriggers, we should be able to accurately pinpoint one FRB a day to its galaxy, which is substantial," Leung said. "That's 20 times better than CHIME, with two outrigger arrays."
With this new precision, optical telescopes can pivot to identify the type of star groups — globular clusters, spiral galaxies — that produce the bursts and hopefully identify the stellar source. Of the 5,000 or so sources detected to date — over 95% of which were detected by CHIME — few have been isolated to a specific galaxy, which has hindered efforts to confirm whether magnetars or any other type of star are the source.
As detailed in the new paper, Shah averaged many bursts from the repeating FRB to improve the pinpointing accuracy provided by the CHIME array and one outrigger array in British Columbia. After its discovery in February 2024, astronomers recorded 21 more bursts through July 31. Since the paper was submitted, Shion Andrew at MIT incorporated data from a second outrigger at the Green Bank Observatory in West Virginia to confirm Shah's published position with 20 times the precision.
“This result challenges existing theories that tie FRB origins to phenomena in star-forming galaxies,” said Shah. “The source could be in a globular cluster, a dense region of old, dead stars outside the galaxy. If confirmed, it would make FRB 20240209A only the second FRB linked to a globular cluster.”
She noted, however, that the other FRB originating in a globular cluster was associated with a live galaxy, not an old elliptical in which star formation ceased billions of years ago.
“It's clear that there's still a lot of exciting discovery space when it comes to FRBs and that their environments could hold the key to unlocking their secrets,” said Tarraneh Eftekhari, who has an Einstein Postdoctoral Fellowship at Northwestern and first author of the second paper.
"CHIME and its outrigger telescopes will let us do astrometry at a level unmatched by the Hubble Space Telescope or the James Webb Space Telescope. It'll be up to them to drill down to find the source," Leung added. "It's an amazing radio telescope."
The studies were supported by Gordon and Betty Moore Foundation, NASA, the Space Telescope Science Institute, the National Science Foundation, the David and Lucile Packard Foundation, the Alfred P. Sloan Foundation, the Research Corporation for Science Advancement, the Canadian Institute for Advanced Research, the Natural Sciences and Engineering Council of Canada, the Canada Foundation for Innovation and the Trottier Space Institute at McGill.
Two NASA rocket missions are taking to the Alaskan skies in hopes of discovering why some auroras flicker, others pulsate, and still others are riddled with holes. Understanding these peculiar features is part of NASA’s goal to understand the space environment around our planet, which can affect both spacecraft and astronauts. The launch window for the missions — which will fly out of the Poker Flat Research Range in Fairbanks, Alaska — opens on Jan. 21, 2025.
Witnessing the aurora borealis, or northern lights, can be a moving experience. As ribbons of color fill the night sky, Earth’s ever-present connection to space is made visually manifest. It can quiet the mind. Yet these serenity-inducing shimmers are sustained by countless tiny collisions, cascades of little crashes, each perpetrated by a wayward electron. They leave gases glowing in their aftermath like smoldering wreckage. For those less romantically inclined, aurora-watching might be considered top-notch rubbernecking.
This metaphor for the aurora is slightly dramatic. But it does highlight the question that Marilia Samara and Robert Michell, both space physicists at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, are after: What sends these electrons careening off course? Like crime scene investigators, Samara and Michell will use clues at the crash site and work backward to investigate the cause. As principal investigators of the two soon-to-launch rocket missions, they plan to fly rockets through active auroras to reveal what sent them on their distructive courses.
The GIRAFF (Ground Imaging to Rocket investigation of Auroral Fast Features) mission comprises two rockets, each carrying the same set of instruments. Each rocket will target a distinct subtype of aurora: one for so-called fast-pulsating auroras, which flash on and off a few times a second, and the other for flickering auroras, which do so up to 15 times a second.
“It looks like the flickering of an old TV,” Michell, who leads the GIRAFF mission, said.
Michell suspects that fast-pulsating versus flickering auroras are fueled by different electron acceleration processes. To find out, his team will launch one rocket into each type of aurora, measuring the energy, quantity, and relative arrival times of the electron populations forming them. The measurements, he hopes, may reveal which acceleration processes are at work and constrain where in near-Earth space they are occurring.
The second rocket mission, led by Samara, will study so-called “black auroras,” where light from an aurora appears to be missing. In the last 25 years, research using the ESA (European Space Agency) and NASA Cluster satellites has hinted that these dark spots may form where the normally incoming stream of electrons reverses direction, escaping back out into space. Of course, not every blank spot in the aurora fits this description. You need to detect outgoing electrons to know it’s the real deal.
“Otherwise that’s not black aurora, it is just the lack of aurora,” said Samara.
Samara’s team will launch their rocket through the black aurora and surrounding regions, surveying the electron populations as they fly through to understand how and why this stream reversal takes place. The mission is called the Black and Diffuse Aurora Science Surveyor. (Its acronym will be left as an exercise to the reader.)
‘The Hardest Part is Still Ahead’
Even in Alaska, where auroras shine most winter nights, flying a rocket through them is no small feat. Above terrestrial winds, the aurora move according to their own principles. To know when to launch, both teams will track the auroras via ground-based cameras at the launch site and at the down-range observatory in Venetie, Alaska, about 130 miles to the northeast along the rockets’ trajectory.
“We’ll be watching these structures moving in the all-sky camera, trying to time it just right,” Michell said.
Since it takes about five minutes to get the rockets to altitude, the teams must aim them not where the auroras are but where they think they will be. Of the many tools at their disposal, experience is the truest guide.
“You do the best you can, but there’s a certain mix of intuition and determination you need,” Samara said.
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Method of Research
Experimental study
Brain immune cells may also be from Mars and Venus
Researchers find that microglia function differently in males versus females, potentially having broad implications for how neurological diseases are studied
A collision happens. Someone is hurt, a head injury, a concussion. Just as the first responders arrive to help the person, inside the brain, another “crew” of responders is busy clearing debris and repairing injured tissue.
This crew is called the microglia - the immune cells of the central nervous system. Microglia are imperative to maintaining neuronal function by clearing toxins in the brain and central nervous system. But if they are overactive, they can damage neurons instead and, in some cases, have been found to promote the progression of neurodegenerative diseases like Alzheimer’s and Parkinson’s.
During development, there are known sex-related differences in how microglia function. But into adulthood, there was thought to be less variation in how they behave. New research from the Del Monte Institute for Neuroscience at the University of Rochester finds that microglia function may not be as similar across sex as once thought. This discovery could have broad implications for how diseases like Alzheimer's and Parkinson's are approached and studied, and points to the necessity of having gender specific research. It is already known that more women are diagnosed with Alzheimer’s and more men are diagnosed with Parkinson’s but it’s unclear as to why.
“It is a fortuitous finding that has repercussions for what people are doing in the field, but also helps us understand microglia biology in a way that people may not have been expecting,” said Ania Majewska, PhD, professor of Neuroscience and the senior author of a study out today in Cell Reports that shows how microglia respond differently in adult male versus female mice when given an enzyme inhibitor to block its microglia survival receptor. “This research has a lot of ramifications for microglia biology and as a result all these diseases where microglia are important in a sex specific manner.”
Pexidartinib or PLX3397 is an enzyme inhibitor commonly used to remove microglia in the lab setting to help researchers better understand the role of these cells in brain health, function, and disease. PLX3397 is also used to treat the rare disease tenosynovial giant cells tumors (TGCT) a condition that causes benign tumors to grow rapidly in the joints.
Researchers in the Majewska Lab were using PLX3397 in male versus female experiments but continued to run into difficulties, so they decided to take a different approach with the inhibitor. Instead of using it to ask other questions, they decided to better understand how microglia were responding to the drug in males versus females.
Linh Le, PhD (‘24), currently a Research Scientist, SetPoint Medical Corp was a graduate student in the Majewska Lab and is first author of this study, found the expected response from microglia to PLX3397 in male mice—it blocked the receptor that signals microglial survival and depleted the microglia. However, Le, et al, were surprised to find that female microglia responded with a different signaling strategy that resulted in increased microglial survival and less depletion.
“These findings are crucial in the rapidly emerging field of developing disease-modifying therapies that target microglia,” said Majewska. “We do not yet know why the microglia are acting differently in the two sexes. I think we'd like to understand how the signaling through this receptor is regulated in different conditions, i.e. hormonal changes, basal state, inflammatory, or an anti-inflammatory state.”
WASHINGTON, Jan. 21, 2025 – If you’ve ever tossed a generous pinch of salt into your pasta pan’s water for flavor or as an attempt to make it boil faster, you’ve likely ended up with a whitish ring of deposits inside the pan.
A group of scientists from the University of Twente in the Netherlands and the French National Institute for Agriculture, Food, and Environment (INRAE), inspired by this observation during an evening of board games and pasta dinner, wondered what it would take to create the most beautiful salt ring inside the pasta pan: Would you need to throw in small salt grains or large ones? In what quantity and how fast? Is there an optimal amount of water inside the pan?
In Physics of Fluids, from AIP Publishing, the group reports their findings about what causes these peculiar salt particle cloud deposits to form. Their experiment is simple to set up, easily reproducible, and inexpensive.
“By the end of our meal, we’d sketched an experimental protocol and written a succession of experiments we wanted to try on my youngest son’s small whiteboard,” said Mathieu Souzy. “It was a great overall experience, because we soon realized our simple observation of daily life conceals a rich variety of physical mechanisms!”
So what’s really going on within the pan? When a single particle is released into a tank of water, it settles to the bottom due to gravity and creates a small wake drag that perturbs the flow of water around it.
“If a large number of particles are released at the same time, neighboring particles experience this flow perturbation generated by all surrounding particles,” said Souzy. “It causes sedimenting (falling) particles to be progressively shifted horizontally, which leads to an expanding circular distribution of the particles.”
When particles reach the bottom rapidly, they form a circular deposit, and the water entrained within the wake of the cloud of particles further pushes the particles radially away. This creates a clean central depletion region.
But if particles are released from a greater height, they sediment (fall) for a longer time and the cloud of particles expands radially — until there’s a large enough space between particles so that the flow perturbations induced by their fellow sedimenting/falling particles become negligible and particles are no longer close enough to form a “cloud.” Then, particles essentially rain down to form a homogeneous circular deposit.
“These are the main physical ingredients, and despite its apparent simplicity, this phenomenon encompasses a wide range of physical concepts such as sedimentation, non-creeping flow, long-range interactions between multiple bodies, and wake entrainment,” said Souzy. “Things get even more interesting once you realize larger particles are more radially shifted than small ones, which means you can sort particles by size just by dropping them into a water tank!”
And yes, Souzy can “create very nice salt rings almost every time” he cooks now.
Physics of Fluids is devoted to the publication of original theoretical, computational, and experimental contributions to the dynamics of gases, liquids, and complex fluids. See https://pubs.aip.org/aip/pof.
A brain-computer interface, surgically placed in a research participant with tetraplegia, paralysis in all four limbs, provided an unprecedented level of control over a virtual quadcopter—just by thinking about moving his unresponsive fingers.
The technology divides the hand into three parts: the thumb and two pairs of fingers (index and middle, ring and small). Each part can move both vertically and horizontally. As the participant thinks about moving the three groups, at times simultaneously, the virtual quadcopter responds, maneuvering through a virtual obstacle course.
It's an exciting next step in providing those with paralysis the chance to enjoy games with friends while also demonstrating the potential for performing remote work.
"This is a greater degree of functionality than anything previously based on finger movements," said Matthew Willsey, U-M assistant professor of neurosurgery and biomedical engineering, and first author of a new research paper in Nature Medicine. The testing that produced the paper was conducted while Willsey was a researcher at Stanford University, where most of his collaborators are located.
While there are noninvasive approaches to allow enhanced video gaming such as using electroencephalography to take signals from the surface of the user's head, EEG signals combine contributions from large regions of the brain. The authors believe that to restore highly functional fine motor control, electrodes need to be placed closer to the neurons. The study notes a sixfold improvement in the user's quadcopter flight performance by reading signals directly from motor neurons vs. EEG.
To prepare the interface, patients undergo a surgical procedure in which electrodes are placed in the brain's motor cortex. The electrodes are wired to a pedestal that is anchored to the skull and exits the skin, which allows a connection to a computer.
"It takes the signals created in the motor cortex that occur simply when the participant tries to move their fingers and uses an artificial neural network to interpret what the intentions are to control virtual fingers in the simulation," Willsey said. "Then we send a signal to control a virtual quadcopter."
The research, conducted as part of the BrainGate2 clinical trials, focused on how these neural signals could be coupled with machine learning to provide new options for external device control for people with neurological injuries or disease. The participant first began working with the research team at Stanford in 2016, several years after a spinal cord injury left him unable to use his arms or legs. He was interested in contributing to the work and had a particular interest in flying.
"The quadcopter simulation was not an arbitrary choice, the research participant had a passion for flying," said Donald Avansino, co-author and computer scientist at Stanford University. "While also fulfilling the participant's desire for flight, the platform also showcased the control of multiple fingers."
Co-author Nishal Shah, incoming professor of electrical and computer engineering at Rice University, explained, "controlling fingers is a stepping stone; the ultimate goal is whole body movement restoration."
Jaimie Henderson, a Stanford professor of neurosurgery and co-author of the study, said the work's importance goes beyond games. It allows for human connection.
"People tend to focus on restoration of the sorts of functions that are basic necessities—eating, dressing, mobility—and those are all important," he said. "But oftentimes, other equally important aspects of life get short shrift, like recreation or connection with peers. People want to play games and interact with their friends."
A person who can connect with a computer and manipulate a virtual vehicle simply by thinking, he says, could eventually be capable of much more.
"Being able to move multiple virtual fingers with brain control, you can have multifactor control schemes for all kinds of things," Henderson said. "That could mean anything, from operating CAD software to composing music."
Researchers Nick Hahn, Ryan Jamiolkowski, Foram Kamdar and Francis Willett at Stanford and Leigh Hochberg at Brown University also contributed to the study.
Study: A real-time, high performance brain-computer interface for finger decoding and quadcopter control (DOI: 10.1101/2024.02.06.578107) (available when embargo lifts)
CAUTION: Investigational Device. Limited by Federal law to investigational use.
