TORONTO, June 4, 2026 鈥� A team led by 91亚色 researchers has discovered the fastest wind near a supermassive black鈥痟ole鈥痚ver鈥痜ound at ultraviolet wavelengths, driven by鈥痶he disc of matter, or quasar, surrounding the black hole.鈥�&苍产蝉辫;

鈥淭his quasar has a black hole of 1.7鈥痓illion鈥痶imes鈥痶he mass of the Sun. That鈥檚 typical. What鈥檚 not typical is that it has gas moving towards us at 30 per cent of the speed of light,鈥� says of the Faculty of Science.鈥���&苍产蝉辫;

The , published by The American Astronomical Society.鈥�&苍产蝉辫;

The research team includes 91亚色 graduate student and lead author Lucas Seaton, graduate student Marianna Veltri, and undergraduate student Zezhou Zhu, along with colleagues from the University of Washington Bothell and other members of the Sloan Digital Sky Survey (SDSS) collaboration.  

鈥淭his quasar, known as J2318 (Jay Twenty-Three Eighteen), can be found in the Great Square in the constellation of Pegasus,鈥� says Seaton. 鈥淚n terms of its speed, this quasar鈥檚 wind could be called a category 79 hurricane,鈥� says Seaton. 鈥淓very category of hurricane is about 20 per cent faster than the category below it. Calling it category 79 gives an idea of just how fast it is, but of course this wind is unlike anything on Earth.鈥濃��&苍产蝉辫; 

Astronomers have known for close to three decades that every large galaxy has a supermassive black hole at its centre, with a mass from millions to billions of times that of the Sun, although contrary to popular belief they do not eat everything in reach. Matter spiraling into one of these black holes forms a disc far bigger than Earth鈥檚 orbit around the Sun and hotter than the surface of the Sun. These discs of hot gas, called quasars, generate enough light to be seen across the observable universe and to drive winds from their surfaces.  

鈥淚n quasars, we often see winds of gas pushed away from the black hole by the light of the quasar,鈥� says Seaton. 鈥淭he wind in J2318 can be seen at ultraviolet wavelengths at velocities up to 30 per cent the speed of light. Even faster winds can be seen at x-ray wavelengths, but J2318 is the fastest ever discovered at ultraviolet wavelengths.鈥�  

Unlike the differences in gas pressure that drive atmospheric winds on Earth, winds from quasars are pushed at least in part by light itself. Individual packets of light (called photons) bounce off or are absorbed by atoms in the gas and accelerate them.   

鈥淨uasars put out so many photons that those tiny pushes add up to extreme velocities,鈥� says Seaton. 鈥淭he problem is, the photons can also remove all the electrons from the atoms, making them invisible. How to push the gas to the speeds we see while keeping the carbon and silicon ions we see intact鈥� it鈥檚 quite a puzzle.鈥�  

The discovery relied on data from two components of the SDSS, an international survey of the night sky to which hundreds of astronomers have contributed since its start in 1998, specifically, the SDSS-IV and the SDSS-V . Veltri flagged the quasar as potentially interesting in SDSS-V in 2023 while an undergrad student at 91亚色. After looking at it using software set up by Zhu, Hall realized it had an extremely fast wind.  

鈥淐anada has a share of the eight-meter-diameter  (also known as Gemini North) in Hawai鈥檌, and we immediately proposed observations with it. They succeeded in confirming its record-breaking wind velocity,鈥� he says, adding that he often involves 91亚色 undergraduates in research as part of his participation in the SDSS.鈥�&苍产蝉辫; 

He explains that 鈥渏ust as a rainbow spreads the Sun鈥檚 light into different wavelengths (colours), the SDSS spreads out the light from certain stars, galaxies, and quasars into what we call their 鈥榮pectra鈥�. From those spectra, with practice, students learn to spot unusual quasars. In the past, only PhD astronomers or graduate students studying for a PhD would have made a discovery like this, but the SDSS enables undergraduates to do so.鈥�  

Study co-author, Associate Professor Paola Rodr铆guez Hidalgo of the University of Washington at Bothell, adds: 鈥淏oth Patrick and I have been working together and with undergraduate students thanks to the SDSS Faculty and Students Team (FAST) initiative that supports these collaborations. Initiatives like this allow students to focus on research while finishing their undergraduate studies. These students will be the next generation of scientists and are already making scientific discoveries.鈥�  

Co-author Liliana Flores, who worked with Professor Rodr铆guez Hidalgo as an undergraduate at UW Bothell and was a FAST participant, says she was thrilled to contribute to the study of this extreme outflow case. 鈥淚 was in charge of fitting the absorption profiles in the quasar spectrum to determine their velocity and equivalent widths. Repeated observations revealed that the amount of absorbed light changes over time. Something in the wind conditions must be changing for that to happen.鈥濃��&苍产蝉辫; 

Veltri assembled measurements of the brightness of the quasar from 20 years of surveys, starting with the original SDSS. That data shows that J2318 is slowly varying in brightness in a way indistinguishable from other quasars. Only by taking detailed measurements of spectra with SDSS was the wind in J2318 revealed.  

Rodr铆guez Hidalgo calls the discovery exciting. 鈥淭hese extreme outflows carry incredible amounts of energy that can affect the galaxies around them. They serve as a sort of missing link: the elusive feedback between the active central region of a galaxy and the rest of the galaxy. While this process has been included in simulations of galaxy formation for decades, a lot more work needs to be done to understand it from observations and make sure the simulations handle it correctly.鈥�  

Searches are continuing for more extremely high velocity outflows from quasars, says Flores. 鈥淚t won鈥檛 be easy to find a faster ultraviolet outflow than that of J2318, but we are continuing this search from the nearby universe to the most distant reaches of the universe that we can see.鈥� 

Joint with:鈥�&苍产蝉辫;
Sloan Digital Sky Survey鈥�&苍产蝉辫;
University of Washington Bothell鈥�&苍产蝉辫;
The Pennsylvania State University (local only)鈥�&苍产蝉辫;

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The new Centre of Excellence will bring together multiple disciplines across the University to develop and deploy artificial intelligence systems to improve health care

TORONTO, April 9, 2026 鈥� As artificial intelligence (AI) becomes increasingly important, especially in the health-care field, 91亚色 continues to play an outsized role. Today, the University announced the launch of a new Centre of Excellence 鈥� Artificial Intelligence for Public Health Advancement (AIPHA) funded through an Ontario Research Fund 鈥� Research Excellence program.

Director General, Applied Public Health Sciences Pamela Ponic of the Science and Policy Integration Branch, Public Health Agency of Canada, Chief Medical Officer of Health for the Ontario Ministry of Health Kieran Moore, and MPP for Whitby Lorne Coe, Parliamentary Assistant to the Minister of Colleges, Universities, Research Excellence and Security all spoke at the lunch-time event.

As a key player in supporting health-care decision making, AIPHA will strengthen external partnerships and accelerate the transfer of knowledge from research to policy and practice, where hospitals, medical practitioners, policymakers and leaders can use it. It will also help bridge the gap between health analytics and real-world socioeconomic conditions further positioning 91亚色 as a national and global leader in AI-integrated public health solutions through research and innovation.

"The launch of AIPHA marks a defining moment for 91亚色 and for the future of public health in Canada. By bringing together expertise across disciplines, from mathematical modelling and AI to health policy and social equity, we are creating something truly transformative: a hub where research doesn't just advance knowledge but directly shapes the decisions that protect and improve people's lives,鈥� says 91亚色 Interim President and Vice-Chancellor Lisa Philipps. 鈥�91亚色 has long been committed to addressing society's most pressing challenges, and AIPHA reflects that mission at its fullest. We are proud to be building the next generation of AI-adept public health leaders right here, and to be positioning Canada as a global force in equitable, evidence-informed health innovation."

As a dedicated, multi-disciplinary and national hub, AIPHA will bring together expertise from across faculties, including in advanced mathematical and computational modelling, precision analytics and multi-source databases. The goal is to integrate epidemiological, clinical, environmental, climate and socioeconomic indicators in newly created AI models, while training the next generation.

鈥淎rtificial intelligence tools are increasingly being used in health-care settings but a coordinated, ethical and equitable approach to ensure the tools use integrated data sources, and that they are being properly tested and deployed for patient good is lacking. The current speed of newly developed AI models is at times outpacing governance,鈥� says Faculty of Science Dean Maydianne Andrade. 鈥淎s a new Centre of Excellence in the Faculty of Science, AIPHA will lead the way toward better integration of these new technologies in a cohesive manner that will help advance public health care.鈥�

Two projects already underway include: Integrating AI with disease transmission dynamics models for informed prevention and control of outbreaks in indoor and mass gathering settings (2025 to 2031) and Advanced mathematical technologies for respiratory infection risk assessment and pharmaceutical intervention scenario analysis (2024 to 2028), both led by AIPHA鈥檚 inaugural director Jianhong Wu.

鈥淭he AI for Public Health Research Centre is a coordinated innovation hub that will help improve health-care efficiency and outcomes, as well as ensure coordinated, ethical and equitable transformation of public health systems,鈥� says AIPHA Director and University Distinguished Research Professor Jianhong Wu of the Faculty of Science. 鈥淭his kind of central hub is much needed in the health-care sector today to ensure emerging AI tools are properly integrated and decision and policy makers are provided with robust information toward developing a more cohesive, ethical and equitable public health-care system.鈥�

AIPHA will integrate epidemiological, clinical, environmental and socioeconomic data into the AI-enabled decision-support systems it develops and deploys to guide equitable and evidence-informed public health action. In ensuring the development of fair and equitable AI systems, the hub will combine not only advanced mathematical and computational modelling and AI and predictive analytics, but also health systems and policy research with social determinants of health and equity frameworks.

AIPHA will act as a research accelerator for large collaborative grants, train the next generation of AI-adept public health leaders and develop pilot AI-integrated protypes for infectious disease modelling, health system resource allocation and climate health risk forecasting.

It will also strengthen Canadian pandemic and emergency preparedness, enhance evidence-based policymaking, support climate-health adaptation strategies, improve health equity outcomes, and increase 91亚色鈥檚 national visibility in AI governance and public health innovation.

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At this point, Avian flu H5N1 is thought to have very limited ability to transmit between humans, but a recent case in British Columbia with an unknown source of transmission has piqued the curiosity and concern of scientists, including 91亚色 Professor Seyed Moghadas.

Did this lone case come about through transmission from an animal or another person, and if it was via human transmission, what methods will control its spread in the human population? Director of 91亚色鈥檚 Agent-Based Modelling Laboratory in the Centre of Excellence in AI for Public Health Advancement, Moghadas and a group of researchers used modelling to understand the best spread control measures should human-to-human transmission become possible.

鈥淭he idea was, let's evaluate some of the interventions that we usually implement at the very earliest stage of a disease outbreak or emerging disease, which we know very little about,鈥� he says.

For the research, ",鈥� published today in Nature Health, various scenarios from isolation to vaccination before or after a spillover event were modelled. It is one of only a few studies that have explicitly modelled outbreak dynamics following spillover into humans or the effectiveness of public health interventions in early and highly uncertain phases of virus development.

As a professor of computational epidemiology and vaccine science in 91亚色鈥檚 Faculty of Science, Moghadas and his colleagues were already collecting data on H5N1 cases in the United States when the Canadian case arose. Given the unknown nature of transmission, the team decided to pivot their work to look at what was happening in B.C.

鈥淭he case in B.C. was of particular interest for us because no definitive source of exposure was identified, including no direct contact with infected animals or known high-risk settings such as poultry farms,鈥� says Moghadas. 鈥淏ecause of that, it came to our attention that maybe there is some sort of transmission going on between humans.鈥�

As far as health and science experts know, H5N1 can only be transmitted among poultry and dairy cattle on farms, as well as through wild birds, and from these animals to humans, but sustained human-to-human transmission has not been established. The person from B.C., however, had no clearly identified exposure and even though human infection from animals is rare, avian influenza H5N1 is considered highly pathogenic and a potentially serious and evolving threat to global public health.

鈥淭his virus was first identified in 1997 in Southeast Asia. This kind of zoonotic virus essentially jumps from the bird or animal side to human side sometimes, mostly it circulates among wild birds,鈥� says Moghadas. 鈥淭here is no confirmation that human-to-human transmission happens as yet in North America.鈥�

The virus has only been in North America since 2022, but surveillance monitoring for it began in 2003 and up until recently there have been close to 1,000 cases reported globally in humans and just under 500 deaths, although the number of cases could be higher because not all cases are likely reported or symptomatic. The virus has not only expanded its geographical range, but also the animal species it can infect.

鈥淓volution of influenza viruses of any type is always a challenge for humans. The flu virus is one of the very rapid mutating pathogens,鈥� he says. The concern is it will mutate to be able to transmit between humans. How viable is it? How easily can it spillover from animals to humans, and how long could the potential chain of transmission from human-to-human become? These are still open questions.

鈥淨uantifying that risk was important for us because that could also give us direction in terms of how bad the disease could be and what strategies will work to contain it,鈥� says Moghadas. 鈥淲e have very few measures in place or a strategy to deal with it at this point, given that the transmission between humans is not established.鈥�

As it is an avian flu virus, it will likely require two doses of a similar vaccine to what was used during the H1N1 pandemic to reduce the risk and severity which often triggers a higher viral load.

The researchers used Abbottsford, B.C. as the location as it is a highly dense poultry farming area. The starting point is after a spillover has happened. 鈥淚f a human became infected, how do we block this single individual to trigger a large outbreak? Or if the infection is going on between humans, can we block these chains and to what degree we can block them?鈥� asks Moghadas. 鈥淲hat is the effectiveness of either self-isolation of symptomatic cases or vaccination of farmers or vaccination of farmers and their household members?鈥�

Even with mitigation measures, someone in the farmer鈥檚 family could potentially be infected by the farmer and then transmit it to someone in the community.

The team evaluated two different types of vaccination strategies. One was reactive, which means that you trigger a vaccination program after a case has been identified somewhere. The second strategy was pre-emptive 鈥� individuals, such as farmers, are vaccinated before any case is identified.

What they found is that reactive vaccination has very limited additional benefits outside of self-isolation, but pre-emptive vaccination adds substantial additional benefits on top of self-isolation.

Should the virus be confirmed to be capable of human-to-human transmission, Moghadas says they want to limit the chain of transmission and minimize the risk of evolution of the virus to become more adapted to human conditions. For now, he says, when cases are identified, the person should self isolate immediately. For the authorized vaccine, it should be meted out quickly to target populations, but that could take several weeks to have population level effectiveness.

鈥淭imely action is a critical part of controlling the spread. Self-isolation of symptomatic cases has a significant effect, but that comes with the caveat that we don't know if everybody who is infected will develop symptoms,鈥� says Moghadas. 鈥淭here could be potential asymptomatic cases we don't identify and by the time we do identify them, they've been already infecting others in the chain of transmission. This case in B.C. was particularly concerning because they could not find the source of infection.鈥�

The concern is not only that the virus might be able to jump from animals to humans, but also the potential for it to mutate during early human transmission chains making it more adaptable to infecting humans. This underscores the risk of local outbreaks with global implications, he says.

鈥淢y research is all about evidence generation for governments, health-care providers and policymakers in public health organizations. We are generating evidence that can be used to at the very least limit the potential for this virus to become another pandemic,鈥� says Moghadas.

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Tiny sliver of Crescent Moon and Venus will also conjunct on first day of spring

TORONTO, March. 17, 2026 鈥� While it may not currently feel like it in parts of the country, this coming Friday marks the first day of spring, known astronomically as Spring Equinox, and this will also bring an increased chance of Aurora viewing in Canada.

鈥淭his March 20 the magnetic fields of the Sun and the Earth work in conjunction with geometry to give us a good chance at Aurora, so fingers crossed for some solar activity,鈥� says 91亚色 Faculty of Science Associate Professor , director of the Allan I. Carswell Observatory at 91亚色.

The Equinox is often described as 'equal day' and 'equal night' but in fact it is just near to when the day and night are most equal for your location, she explains. At higher latitudes the inequality between the lengths of our days and nights grows. The Equinox could be described as the time when Earth is most evenly facing the Sun. 

That in itself is a bit of a trick, says Hyde, as Earth's axis is tilted about 23.5 degrees away from the plane of the solar system. So, if you imagine the Sun, the Earth and the planets all in a line, Earth would be orbiting the Sun tilted just a bit away or towards it depending on where it is in the orbit. This leads to the seasons and at the Equinox the Earth's magnetic poles are tilted nearly at a right angle to the flow of solar wind from our Sun two times a day. This 'equinoctial effect' presents a bigger target for charged particles to hit. 

鈥淎s the seasons change to Summer or Winter, the poles point either more toward or away from the Sun, reducing this effect,鈥� says Hyde. 

This same alignment near the Equinox also means that the magnetic fields of the Earth and Sun can line up in a way that could allow them to connect. 

鈥淭his is when the 'north-south' of Earth's magnetic field is opposite the Sun's, and opposites attract in magnets,鈥� says Hyde. 鈥淭his is called the Russel-McPherron effect and together the two effects can lead to more frequent and brighter auroras when the Sun is active.鈥�

The Sun is currently in the most intense phase of its 11-year cycle, moving from minimum to maximum activity or vice-versa. In general, near the maximum we always see more solar activity, but there is also an increase near the Equinox to look forward to.聽

As an extra astronomy bonus, with the New Moon on March 19, we also have a conjunction between a very faint sliver of a Crescent Moon and the planet Venus this Friday. In Ontario this will occur near sunset in the West, low on the horizon, so observers with a clear view in that direction will get an extra treat.

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91亚色 is a modern, multi-campus, urban university located in Toronto, Ontario. Backed by a diverse group of students, faculty, staff, alumni and partners, we bring a uniquely global perspective to help solve societal challenges, drive positive change, and prepare our students for meaningful life and career paths. 91亚色's Glendon Campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education. 91亚色鈥檚 campus in Costa Rica offers students exceptional transnational learning opportunities and innovative programs. Together, we can make things right for our communities, our planet, and our future.

Media Contact: Emina Gamulin, 91亚色 Media Relations, 437-217-6362, egamulin@yorku.ca

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91亚色 U led study found clear vaccine-initiated immune response biomarkers between HIV positive and HIV negative groups, but outliers underscore varied, intricate nature of the immune system

How people with compromised immune systems respond to vaccines is an important area of immunological research. A led by 91亚色 found that not only could machine-learning models accurately pinpoint differences in healthy controls and those living with HIV, but also found outliers in both groups that provide fascinating glimpses into the complex nature of the immune system and what personalized medicine could look like in the future, accounting for variables such as age, comorbidities and genetics.

鈥淭his study constitutes an important step forward in the potential for personal vaccination intervention strategies,鈥� says lead author Chapin Korosec, who worked on this paper as a postdoctoral fellow at 91亚色 under the supervision of Faculty of Science Professor , whose research focuses on infectious disease modelling. 鈥淏y learning the structure of immune variability at scale, we move toward a data-driven foundation for personalized vaccination and therapeutic design.鈥�

Korosec, now an adjunct professor with the University of Guelph, used a dataset of people with and without HIV who had received up to five doses of COVID-19 vaccine over the course of 100 weeks. All the individuals living with HIV were from the Greater Toronto Area whose illness was being controlled with antiretroviral therapy. The researchers used a type of machine-learning method called random forest to analyze 64 immune biomarkers elicited through a response to the COVID-19 vaccine, and then created a group of 鈥榲irtual patients鈥� to further model immune responses.

鈥淲hile we were working with a rich dataset well suited for statistical testing, longitudinal mathematical models still face identifiability limits when the data cannot uniquely resolve immune dynamics. We therefore turned to machine learning to identify the core differences between groups, and then leveraged that learned structure to generate virtual patients that capture how immune patterns differ between groups.鈥�

They were able to show that saliva-based antibodies, particularly a type of antibody in the saliva called IgA, coupled with white blood cells, which have long been known to be associated with HIV status, create the signature difference between the two groups. Korosec says this is significant because there is a lot of research showing altered mucosal immunity for those living with HIV and how it is influenced in the short and long term.

Heffernan notes that they identified subgroups within the HIV positive group, which highlights the importance of personalized vaccination strategies and the challenges of modelling immune responses due to individual variability.

鈥淭he immune response is very, very complicated.鈥� explains Heffernan. 鈥淪ometimes something can act as an inhibitor of an arm of the immune response, but in other times it might be an activator. There is also a lot of individual variability among people with similar immune system status. Using machine learning, mechanistic modelling, and 鈥榲irtual patients鈥� we can try to uncover important differences in the subgroups and between individuals 鈥� even of immune system components that are not measured in the data. Kind of like trying to find the needle in a haystack, but with a clearer path to finding it.鈥�

The HIV positive group, despite having the benefits of antiretroviral therapy, had clear differences in their vaccine-elicited responses compared to the control group and the machine-learning model was able to classify those differences with nearly 100 per cent accuracy, but there were two individuals who they could not differentiate from the control group.

鈥淣o matter how we shuffled the data or which biomarkers we used, the machine-learning algorithm could not distinguish a small subset of HIV-positive individuals from those who were HIV-negative,鈥� says Korosec. 鈥淚n those individuals, the vaccine-induced immune responses were indistinguishable from the HIV-negative group. That suggests that, at least in terms of vaccination response, their immune function was effectively restored.鈥�

Conversely, there was one individual in the healthy control group whose markers looked indistinguishable from someone living with HIV, which may suggest underlying immune issues that may not yet have been clinically identified.

Supported by the National Research Council of Canada (NRC)-Fields Mathematical Sciences Collaboration Centre, the National Sciences and Engineering and Research Council of Canada and Artificial Intelligence for Public Health (AI4PH), the study was published today as a pre-print in the Journal Patterns and will appear in print as the cover article on March 13. Korosec worked with collaborators, including Heffernan,  Senior Research Officer Mohammad Sajjad Ghaemi from the NRC Digital Technologies Research Centre, Associate Professor Jessica Conway from Pennsylvania State University and researchers from the University of Toronto and St. Michael鈥檚 Hospital.

鈥淭his study moves us closer to understanding immune diversity in people living with HIV; how their responses compare to age-matched controls, how well antibodies are maintained over time, and why some individuals show strikingly different patterns,鈥� says Korosec.

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91亚色 is a modern, multi-campus, urban university located in Toronto, Ontario. Backed by a diverse group of students, faculty, staff, alumni and partners, we bring a uniquely global perspective to help solve societal challenges, drive positive change, and prepare our students for meaningful life and career paths. 91亚色's Glendon Campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education. 91亚色鈥檚 campus in Costa Rica offers students exceptional transnational learning opportunities and innovative programs. Together, we can make things right for our communities, our planet, and our future.

Media Contact: Emina Gamulin, 91亚色 Media Relations, 437-217-6362, egamulin@yorku.ca

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91亚色 researchers say the decrease in the smallest PFAS during COVID points to its sources and the potential to change the environmental levels of it in the future

TORONTO, Jan. 29, 2026 鈥� A new study out of 91亚色 has found that the amount of atmospheric trifluoroacetic acid (TFA), the tiniest forever chemical, significantly declined in Toronto during COVID in 2020, which researchers say is good news for the world鈥檚 ability to mitigate it in the future.

鈥淲hen we turned off the tap, so to speak, and we all went home and stopped normal activities, we saw a really quick response, a dramatic reduction of TFA. But the real surprise is that the results point to TFA being formed from short-lived chemical precursors emitted into the atmosphere,鈥� says 91亚色 atmospheric chemist Professor Cora Young, senior author of the paper published today. 鈥淚 was so surprised when we saw that it had decreased during the pandemic, but I had to double and triple check the data because I didn鈥檛 believe it at first.鈥�

The reason it is such good news, says Young is 鈥渢hat when there is an immediate response after emissions reduction, it tells us that we should be able to figure out how to minimize the emissions and control the formation of TFA in the future. We could have a lot more control over this than we previously thought and that鈥檚 very exciting. If we don't know where it's coming from, it's very difficult for us to regulate.鈥�

Unfortunately, as people returned to work and daily life, these levels have crept back up and they peak in the summer when there is more light, which is needed for its creation. A short-chain per- and polyfluoroalkyl substance (PFAS), TFA forms in the atmosphere when various chemical emissions come together.

鈥淭FA is something that we haven't known a lot about before, but we're learning more now that we can measure it,鈥� says 91亚色 PhD Candidate Daniel Persaud, the paper鈥檚 lead author. 鈥淲ith levels of TFA dropping during the pandemic, it now gives us a lot more information about its thousands of sources, such as industrial and vehicle air conditioner emissions.鈥�

The researchers collected and analyzed monthly measurements of both wet (rain and snow) and dry deposition 鈥� gases and particles that land on surfaces and form a layer of dust, for example, on windows and car windshields 鈥� from the Air Quality Research Station on roof of 91亚色鈥檚 Petrie Science and Engineering Building between 2018 to 2024.

What is still unknown, is the effect of long-term exposure on people and wildlife. Young says TFAs are already orders of magnitude higher in the environment than some of the other PFAS, such as perfluorooctanoic acid, known as PFOA. PFOA was the subject of successful lawsuits with hundreds of millions in payouts, including from DuPont, which is also the focus of the 2019 documentary Dark Waters.

鈥淭he short-chain PFAS precursors were supposed to be more benign, and many are, but not all and so that created more unknowns about their effect. There is preliminary evidence that is behaving in ways we didn't expect. We鈥檙e finding it at high concentrations in food, for example,鈥� says Young of 91亚色 Faculty of Science.

鈥淲e didn鈥檛 think that PFASs like TFA could bioaccumulate, but they鈥檝e been found to accumulate in plants, and can be found in the food people and wildlife eat. It has even been found in human blood. Our exposure could still be quite high, even if it's not bioaccumulating. If TFA levels in the environment are driven by short-lived emissions, then that鈥檚 something we can actually address now.鈥�

A little history

The main precursor chemicals that form short-chain PFASs are the second generation of chemicals designed to replace the ozone-depleting chlorofluorocarbons (CFCs), phased out globally starting with the 1987 Montreal Protocol. These first-generation replacement chemicals remain for years to decades in the atmosphere and can slowly react to form short-chain, persistent PFAS, like TFA, thought to be better than CFCs at the time, but these forever chemicals are now found everywhere from the Arctic to the Antarctic and there is no way to turn back the clock on them.

鈥淭he change from long-lived to short-lived precursors was made for climate reasons because the long-lived ones are also really potent greenhouse gases,鈥� says Persaud of the Faculty of Science. 鈥淲e previously though the biggest source of TFA was first-generation CFC replacements, but our results show the important role of short-lived, next-generation replacements.鈥�

An example of that change is that in North America all car air conditioners from 2019 onwards now use a short-lived TFA precursor rather than the long-lived PFAS precursors. However, if these performance chemicals for air conditioners are finding their way into the atmosphere, it鈥檚 expensive for car manufacturers and consumers for alike.

The paper, , was published in journal Environmental Science & Technology Letters.

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The combined results add to physicists鈥� understanding and they validate the impressive collaborative effort
between two competing 鈥� yet complementary 鈥� experiments.

TORONTO, Oct. 22, 2025 鈥� The (T2K) experiment in Japan and the (NOvA) experiment in the United States, previously considered rival experiments, conducted a joint analysis and published their first results today in the journal .

Both are long-baseline neutrino oscillation experiments using accelerators, and by leveraging their different baselines and neutrino energies, they achieved precision measurements of neutrino oscillations.

Neutrinos are subatomic particles that are neutral and weigh almost nothing, and almost never interact with the matter around them, making them notoriously hard to study. However, they may hold the secret to why the universe is now filled with matter and light. Everything known about particle physics tells scientists that when the universe began there were equal amounts of matter and antimatter, which when they collide, annihilate to form light.

鈥淚f matter and antimatter behave identically, then the universe now should hold nothing but light.聽 Something must have tipped the balance to favour matter over antimatter, and all the other particles we have studied till now cannot tip this balance. It is possible that neutrinos may be what tipped that balance, so the field is trying as hard as it can to see if neutrinos and antineutrinos behave differently from each other,鈥� says 91亚色 Professor Deborah Harris.

Harris, a particle physicist in the Department of Physics and Astronomy, Faculty of Science, is an active member of the large research collaboration T2K.  She also collaborates on a next generation neutrino oscillation experiment aiming to measure oscillations with even more precision, called the Deep Underground Neutrino Experiment (DUNE), and is a senior scientist at Fermi National Accelerator Laboratory in the United States. 

The combined efforts of T2K and NOvA succeeded in reducing the uncertainty in the differences between neutrino masses to below two per cent. Although the ordering of the three neutrino masses is still unknown, their results show that depending on this ordering, the magnitude of CP symmetry violation 鈥� a difference in behaviour between particles and antiparticles 鈥� would be strongly constrained.

This achievement marks an important step toward uncovering CP symmetry violation in neutrinos and the origin of the matter鈥揳ntimatter asymmetry in the universe. The joint analysis combined 10 years of T2K data collected since 2010 and six years of NOvA data collected since 2014, and it also demonstrates the strength of collaboration between two international experiments that are competitive yet complementary.

鈥淭his combination does not yet see a definitive difference between neutrinos and antineutrinos but by combining the two experiment鈥檚 data we know much more about neutrinos than either experiment can tell us by itself,鈥� says Harris.

91亚色 researchers have been an important part of T2K since its inception and contributed the critical Optical Transition Radiation Detector in the beamline. These researchers include Professor Sampa Bhadra and postdoctoral Fellows Dr. No毛 Roy and Dr. Arturo Fiorentini, and former PhD students Dr. Rowan Zaki and Dr. Mitchell Yu.    

Context

When the universe began, physicists expect there should have been equal amounts of matter and antimatter. But if that were so, the matter and antimatter should have perfectly canceled each other out, resulting in total annihilation.

And yet, here we are. Somehow, matter won out over antimatter 鈥� but we still don鈥檛 know how or why.

Physicists suspect the answer may lie in the mysterious behaviour of abundant yet elusive particles called neutrinos. Specifically, learning more about a phenomenon called neutrino oscillation 鈥� in which neutrinos change types, or flavours, as they travel 鈥� could bring us closer to an answer.

The international collaborations representing two neutrino experiments, T2K in Japan and NOvA in the United States, recently combined forces to produce their first joint results, published today in the journal Nature. This initial joint analysis provides some of the most precise neutrino-oscillation measurements in the field.

鈥淭hese results are an outcome of a cooperation and mutual understanding of two unique collaborations, both involving many experts in neutrino physics, detection technologies and analysis techniques, working in very different environments, using different methods and tools,鈥� says T2K collaborator Tom谩拧 Nosek.

Different experiments, common goals

Despite their ubiquity, neutrinos are very difficult to detect and study. Even though they were first seen in the 1950s, the ghostly particles remain deeply enigmatic. Filling in gaps in our knowledge about neutrinos and their properties may reveal fundamental truths about the universe.

T2K and NOvA are both long-baseline experiments: they each shoot an intense beam of neutrinos that passes through both a near detector close to the neutrino source and a far detector hundreds of miles away. Both experiments compare data recorded in each detector to learn about neutrinos鈥� behaviour and properties.

NOvA, the NuMI Off-axis 谓_e Appearance experiment, sends a beam of neutrinos 810 kilometers from its source at the U.S. Department of Energy鈥檚 Fermi National Accelerator Laboratory near Chicago, Ill., to a 14,000-ton liquid-scintillator detector in Ash River, Minnesota.

The T2K experiment鈥檚 neutrino beam travels 295 kilometers from Tokai to Kamioka 鈥� hence the name T2K. Tokai is home to the Japan Proton Accelerator Research Complex (J-PARC) and Kamioka hosts the Super-Kamiokande neutrino detector, an enormous tank of ultrapure water located a kilometer underground.

Since the experiments have similar science goals but different baselines and different neutrino energies, physicists can learn more by combining their data.

鈥淏y making a joint analysis you can get a more precise measurement than each experiment can produce alone,鈥� says NOvA collaborator Liudmila Kolupaeva. 鈥淎s a rule, experiments in high-energy physics have different designs even if they have the same science goal. Joint analyses allow us to use complementary features of these designs.鈥�

As long-baseline experiments, NOvA and T2K are ideal for studying neutrino oscillations, a phenomenon that can provide insight into open questions like charge-parity violation and the neutrino mass ordering. Two experiments with different baselines and energies have a better chance of disentangling the two effects than one experiment alone.

Interrogating neutrino oscillations

The mystery of neutrino mass ordering is the question of which neutrino is the lightest. But it isn鈥檛 as simple as placing particles on a scale. Neutrinos have miniscule masses that are made up of combinations of mass states. There are three neutrino mass states, but, confusingly, they don鈥檛 map to the three neutrino flavours. In fact, each flavour is made of a mix of the three mass states, and each mass state has a different probability of acting like each flavour of neutrino.

There are two possible mass orderings, called normal or inverted. Under the normal ordering, two of the mass states are relatively light and one is heavy, while the inverted ordering has two heavier mass states and one light.

In the normal ordering, there is an enhanced probability that muon neutrinos will oscillate to electron neutrinos but a lower probability that muon antineutrinos will oscillate to electron antineutrinos. In the inverted ordering, the opposite happens. However, an asymmetry in the neutrinos鈥� and antineutrinos鈥� oscillations could also be explained if neutrinos violate CP symmetry 鈥� in other words, if neutrinos don鈥檛 behave the same as their antimatter counterparts.

The combined results of NOvA and T2K do not favour either mass ordering. If the neutrino mass ordering is found to be normal, NOvA鈥檚 and T2K鈥檚 results are less clear on CP symmetry, requiring additional data to clarify. However, if future results show the neutrino mass ordering is inverted, the results published today provide evidence that neutrinos violate CP symmetry, potentially explaining why the universe is dominated by matter instead of antimatter.

鈥淣eutrino physics is a strange field. It is very challenging to isolate effects,鈥� says Kendall Mahn, co-spokesperson for T2K. 鈥淐ombining analyses allows us to isolate one of these effects, and that鈥檚 progress.鈥�

The combined analysis does provide one of the most precise values of the difference in mass between neutrino mass states, a quantity called 螖m²₃₂. With an uncertainty below two per cent, the new value will enable physicists to make precision comparisons with other neutrino experiments to test whether the neutrino oscillation theory is complete.

What鈥檚 next

These first joint results do not definitively solve any mysteries of neutrinos, but they do add to physicists鈥� knowledge about the particles. Plus, they validate the impressive collaborative effort between two competing 鈥� yet complementary 鈥� experiments.

The NOvA collaboration consists of more than 250 scientists and engineers from 49 institutions in eight countries. The T2K collaboration has more than 560 members from 75 institutions in 15 countries. The two collaborations began active work on this joint analysis in 2019. It combines six years of data from NOvA, which began collecting data in 2014, and a decade of data from T2K, which started up in 2010.聽 Both experiments continue to take data, and efforts are already underway to update the joint analysis with the new data.

鈥淭he joint analysis work has benefited both collaborations,鈥� says Patricia Vahle, co-spokesperson for NOvA. 鈥淲e have a much better mutual understanding of the strengths and challenges of the different experimental setups and analysis techniques.鈥�

NOvA and T2K are the only currently operating long-baseline neutrino experiments. Their initial combined results lay a foundation for forthcoming neutrino experiments that will answer the questions around neutrinos unambiguously.

The Fermilab led Deep Underground Neutrino Experiment is under construction in Illinois and South Dakota in the U.S. With its longer baseline of 1,300 kilometers, DUNE will be more sensitive to neutrino mass ordering and could give physicists a conclusive answer shortly after it turns on in the early years of the next decade.

In Japan, Hyper-Kamiokande, the successor to Super-Kamiokande, is currently under construction in an underground mine in Kamioka, Hida City, Gifu Prefecture, with experiments scheduled to begin in 2028. Hyper-Kamiokande will conduct highly sensitive searches for CP symmetry violation through high-statistics measurements made possible by a detector about eight times larger and an intense neutrino beam.

Many physicists hope these next-generation neutrino experiments can come together 鈥� as NOvA and T2K have already done 鈥� to make progress on their shared scientific goals to learn more about neutrinos and their unusual properties.

鈥淎s shown in this very analysis, there are no truly 鈥榬ivaling鈥� experiments because they all share a common goal of scientific study of a phenomenon,鈥� says Nosek. 鈥淐ollaborating is naturally important for the transfer of knowledge, know-how and experience, and for sharing resources, ideas and tools. The T2K-NOvA collaboration is not merely a sum of T2K and NOvA collaborations. It is much, much more.鈥�

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Researchers use newly deployed CHIME Outrigger telescopes and deep-space imaging to challenge long-held assumptions about what causes the mysterious cosmic signals

A team of international astronomers, including a researcher from 91亚色, have pinpointed one of the brightest fast radio bursts (FRBs) ever detected to a location in a nearby galaxy. The finding and the location surprised the team and offered new insight into FRBs, which are one of astrophysics鈥� biggest mysteries.

FRBs are powerful, millisecond-long flashes of radio waves from space. Researchers suspect that they are the result of extreme cosmic events but have, so far, been unable to determine the exact origin of any of them. FRBs are notoriously difficult to study because they vanish in the time it takes to blink. For the past years, CHIME has been casting a broad net to catch the rarest astrophysical events. Now it can also pinpoint their origin.

鈥淭his was the brightest fast radio burst that the CHIME Telescope has ever seen,鈥� says Assistant Professor Paul Scholz, a coordinator on the CHIME/FRB project and author of one of the papers outlining the discovery. 鈥淧reviously, most of the fast radio bursts were detected halfway across the universe, where they鈥檙e extremely distant. This one was in a galaxy that's very close to us.鈥�

A particularly bright FRB was detected in March from the direction of the Big Dipper by the Canadian CHIME/FRB radio-telescope. Referred to as FRB 20250316A, affectionately dubbed 鈥淩BFLOAT鈥� for Radio Brightest FLash Of All Time, the FRB marks a significant change for researchers because it allowed for the identification of a point of origin using only CHIME/FRB, the most prolific FRB discovery machine.

鈥淭his result marks a turning point: instead of just detecting these mysterious flashes, we can now see exactly where they鈥檙e coming from. It opens the door to discovering whether they鈥檙e caused by dying stars, exotic magnetic objects, or something we haven鈥檛 thought of yet,鈥� said Amanda Cook, a McGill-based Postdoctoral Researcher, who led the study that announced the discovery.

鈥楲ike spotting a quarter from 100km away鈥�

To investigate RBFLOAT鈥檚 origin, the researchers relied on CHIME鈥檚 newly completed 鈥渙utrigger鈥� telescopes, which span North America from British Columbia to California. This array of vantage points gave them unprecedented spatial resolution, allowing them to trace the burst to a region just 45 light years across 鈥� smaller than the average star cluster 鈥� in the outskirts of a galaxy about 130 million light-years away.

鈥淭he precision of this localization, tens of milliarcseconds, is like spotting a quarter from 100 kilometres away,鈥� said Cook. 鈥淭hat level of detail is what let us identify the host galaxy, NGC 4141, and match the burst with a faint infrared signal captured by the James Webb Space Telescope.鈥�

That, in turn, revealed a mysterious source of near-infrared light in the exact spot where RBFLOAT occurred. This surprised the researchers who are left wondering if the spot is something like a red giant star or a fading light echo from the burst itself.

鈥淭he high resolution of JWST allows us to resolve individual stars around an FRB for the first time. This opens the door to identifying the kinds of stellar environments that could give rise to such powerful bursts, especially when rare FRBs are captured with this level of detail.鈥� said Peter Blanchard, a Harvard Research Associate and lead author of the other paper.

Despite being the brightest yet seen by CHIME, researchers have not detected repeat bursts from the source, even in the hundreds of hours its position was observed by the CHIME survey instrument over more than six years. That goes against the prevailing idea that all FRBs eventually repeat.

鈥淚t seems different energetically than the repeaters we鈥檝e studied. We鈥檙e now re-examining some of the more explosive models that had fallen out of favour,鈥� said  Mawson Sammons, a postdoctoral researcher at McGill. Sammons works with Victoria Kaspi, astrophysicist and professor at McGill, who co-leads the CHIME/FRB research team of roughly 100 scientists.

New possibilities

The new observations are described through two studies, the first of which Scholz was an author on. The first is focused on the and localization of the burst, and the other on of the location from which the radio burst originated. Together, they provide detail and new possibilities for studying FRBs, not just as cosmic curiosities but as tools to probe the universe.

鈥淭his marks the beginning of a new era where we can routinely localize even single, non-repeating bursts to pinpoint precision. That鈥檚 a game-changer for understanding what鈥檚 behind them,鈥� said Sammons.

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91亚色 is a modern, multi-campus, urban university located in Toronto, Ontario. Backed by a diverse group of students, faculty, staff, alumni and partners, we bring a uniquely global perspective to help solve societal challenges, drive positive change, and prepare our students for success. 91亚色's fully bilingual Glendon Campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education. 91亚色鈥檚 campuses in Costa Rica and India offer students exceptional transnational learning opportunities and innovative programs. Together, we can make things right for our communities, our planet, and our future. 

Media Contact: Emina Gamulin, 91亚色 Media Relations, 437-217-6362, egamulin@yorku.ca

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Novel models of planetary interiors give scientists a framework to interpret current observations of distant exoplanets from space- and ground-based telescopes

TORONTO, July 29, 2025 鈥� A new paper led by a 91亚色 professor and in Nature Astronomy introduces a simple theoretical framework to describe the evolution of the coupled interior鈥揳tmosphere system of hot rocky exoplanets known as 鈥渓ava planets.鈥�

鈥淟ava planets are in such extreme orbital configurations that our knowledge of rocky planets in the solar system does not directly apply, leaving scientists uncertain about what to expect when observing lava planets,鈥� says first author Charles-脡douard Boukar茅, Assistant Professor in 91亚色鈥檚 Department of Physics and Astronomy in the Faculty of Science.

鈥淥ur simulations propose a conceptual framework for interpreting their evolution and provide scenarios to probe their internal dynamics and chemical changes over time. These processes, though greatly amplified in lava planets, are fundamentally the same as those that shape rocky planets in our own solar system.鈥�

Exotic worlds may unveil processes driving planetary evolution

Lava planets are Earth- to super-Earth鈥搒ized worlds orbiting extremely close to their host stars, completing an orbit in less than a single Earth day. Much like Earth鈥檚 Moon, they are expected to be tidally locked, always showing the same face to their star. Their dayside surfaces reach such extreme temperatures that silicate rocks melt 鈥� and even vaporize 鈥� creating conditions unlike anything in our solar system. These exotic worlds, easily observable due to their ultra short orbital period, provide unique insights into the fundamental processes that shape planetary evolution.

Probing planetary interiors through atmosphere and surface properties

The study combines expertise in geophysical fluid mechanics, exoplanetary atmospheres, and mineralogy to explore how the compositions of lava planets evolve through a process akin to distillation. When rocks melt or vaporize, elements such as magnesium, iron, silicon, oxygen, sodium, and potassium partition differently between vapor, liquid, and solid phases. The unique orbital configuration of lava planets maintains vapor鈥搇iquid and solid鈥搇iquid equilibria over billions of years, driving long-term chemical evolution.

The paper, 鈥淭he role of interior dynamics and differentiation on the surface and atmosphere of lava planets,鈥� was co-authored by Daphn茅 Lemasquerier (University of St Andrews), Nicolas B. Cowan (McGill University), Lisa Dang (University of Waterloo),  Henri Samuel, James Badro, Aur茅lien Falco and S茅bastien Charnoz (Universit茅 Paris Cit茅).

Using unprecedented numerical simulations, the team predicts two end-member evolutionary states:

            鈥� Fully molten interior (likely young planets): The atmosphere mirrors the bulk planetary composition, and heat transport within the molten interior keeps the nightside surface hot and dynamic.

            鈥� Mostly solid interior (likely older planets): Only a shallow lava ocean remains on the dayside, and the atmosphere becomes depleted in elements such as sodium, potassium, and iron.

Testing hypotheses with the James Webb Space Telescope

Boukar茅 explains that this research on lava exoplanets began as a highly exploratory effort with few initial expectations. It builds on a novel modeling approach he developed to study molten rocky planets in collaboration with colleagues at the Institute de Physique du Globe de Paris, Universit茅 Paris Cit茅, published in Nature earlier this year.

What began as an exploratory study has since opened a promising new line of research. The predictions outlined in this work helped secure 100 hours of observation time on the James Webb Space Telescope (JWST) 鈥� the most advanced infrared observatory ever built, featuring a 6.5鈥憁etre segmented mirror and ultra鈥憇ensitive instruments capable of probing the earliest galaxies and the atmospheres of distant exoplanets with unprecedented precision. These upcoming JWST observations, led by co-author Prof. Dang, will directly test the theoretical framework proposed in this study.

鈥淲e really hope we can observe and distinguish old lava planets from young lava planets. If we can do this, it would mark an important step toward moving beyond the traditional snapshot view of exoplanets,鈥� says Boukar茅.

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91亚色 is a modern, multi-campus, urban university located in Toronto, Ontario. Backed by a diverse group of students, faculty, staff, alumni and partners, we bring a uniquely global perspective to help solve societal challenges, drive positive change, and prepare our students for success. 91亚色's fully bilingual Glendon Campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education. 91亚色鈥檚 campuses in Costa Rica and India offer students exceptional transnational learning opportunities and innovative programs. Together, we can make things right for our communities, our planet, and our future. 

Media Contact: Emina Gamulin, 91亚色 Media Relations, 437-217-6362, egamulin@yorku.ca

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