Research & Innovation

Using data from the James Webb Space Telescope, Jacqueline Antwi-Danso is examining the light emitted by distant, "quenched" galaxies to learn about their chemical composition and other properties

Everything we thought we knew about galaxy formation was thrown into question in the 1990s after astronomers discovered two distant, massive galaxies that had completely stopped – or “quenched” – their star formation.

“The discovery meant that these galaxies [had to be] older than the age of the universe, which is physically impossible,” says Jacqueline Antwi-Danso, the NSERC Banting Postdoctoral Fellow at University of Toronto’s David A. Dunlap department for astronomy and astrophysics in the Faculty of Arts & Science.

“When we look at the formation histories of these distant quenched galaxies, the observations suggest that they formed too quickly and too early compared to what we see in cosmological simulations.”

Unlike familiar massive galaxies like the Milky Way, which have up to a trillion stars and are characterized by luminous, spiral-like arms of active star formation, distant, quenched galaxies are composed of old stars and look like small orange-red blobs. This is because their light has been “stretched out” to infrared wavelengths due to the expansion of the universe, which also makes them fainter and harder to spot.

Moreover, the distant galaxies in question formed within a billion years of the Big Bang (which happened nearly 14 billion years ago). In other words, they formed their stars extremely rapidly – unlike any galaxy observed in the present-day.

Better understanding these distant galaxies is a high priority for researchers since their extreme star-formation processes are uncomfortably close to the limits permitted by current galaxy formation physics.

At �山ǿ��, Antwi-Danso is hunting the earliest distant quenched galaxies in the universe and is particularly interested in finding out how these galaxies formed and when they stopped creating stars. She is building on findings from a study she participated in as a PhD student at Texas A&M University that led to two critical discoveries. The first was the identification of two new distant quenched galaxies that confirmed current thinking on how these distant galaxies formed – “namely,” Antwi-Danso says, “that these galaxies form too early and too quickly based on what theory predicts.”

The study – which used the 8-meter telescope at the Gemini South Observatory based in Chile and surveyed large areas of the sky with new imaging filters – also highlighted that astronomers can reliably use ground-based telescopes to observe distant quenched galaxies as old as 12.5 billion years. Detecting galaxies any earlier than this requires space-based data, the researchers say.

Astronomers are now rethinking long-standing models of galaxy formation as they observe distant quenched galaxies with supermassive black holes at their centres that emit energetic radiation. This is important, Antwi-Danso says, because the differing models for light emission from stars and supermassive black holes can affect estimates of the physical properties of these distant galaxies.

Harnessing the power of space-based technology

Distant galaxies are difficult to detect because the light they emit is shifted to infrared wavelengths, which is mostly blocked by the Earth’s atmosphere. So, the next stages of Antwi-Danso’s research will leverage the power of the James Webb Space Telescope (JWST).

The JWST – which launched in December 2021 – is about 100 times more sensitive than the largest ground-based infrared telescopes and can observe galaxies in a fraction of the time of its predecessors. In fact, it has doubled the number of spectroscopic observations of the most distant, quenched galaxies within only two years of operation.

To further observe the two distant galaxies she discovered from Chile, Antwi-Danso will use JWST data to examine their spectra – the light emitted by these galaxies over a range of wavelengths – to reveal information like chemical composition. These and other findings will help provide a more accurate understanding of the galaxies’ formation histories and can be compared with updated cosmology simulations. That, in turn, may yield new insights about potential tensions between theory and observations.

Antwi-Danso is also part of the CAnadian NIRISS Unbiased Cluster Survey (CANUCS), a multi-institutional collaboration that uses gravitational lensing – a phenomenon where a massive object acts as a cosmic magnifying glass – to study the building blocks of the earliest galaxies. Within that collaboration, Antwi-Danso is also a researcher on the Technicolor Survey, which employs multiple filters on the JWST’s near-infrared camera to observe quenched galaxies at wavelengths that are inaccessible from the ground.

“We want to find galaxies that contain the first generations of stars, and then model their observations with galaxy formation models to infer their physical properties and star formation histories,” Antwi-Danso says.

With the technological advantages provided by the JWST to push the boundaries of distant galaxy observations, Antwi-Danso’s research will provide valuable insights into understanding how early galaxies came to be.

“We’re really excited to see where the results lead and to compare those observations with current theoretical predictions for these distant massive galaxies.”

Read a Q&A with Jacqueline Antwi-Danso

Researchers shed light on the experiences of caregivers in Nunavut's family service system

Christopher.Sorensen — Thu, 14 Nov 2024 18:22:13 +0000

Researchers shed light on the experiences of caregivers in Nunavut's family service system

Christopher.Sorensen Thu, 11/14/2024 - 13:22

Cutline

Researchers at OISE and the Umingmak Centre have released a report that provides insights into the experiences of caregivers of children involved in Family Services in Iqaluit, Nunavut (photo by Saffron Blaze)

Marianne Lau

Topic

Breaking Research

Nunavut

Ontario Institute for Studies in Education

Research & Innovation

Subheadline

Nunavut's Umingmak Centre partnered with the Critical Health and Social Action Lab at OISE to better understand the needs of caregivers and enhance child advocacy in the territory

Researchers at the Umingmak Centre, a child advocacy centre in Nunavut, and the University of Toronto’s Ontario Institute for Studies in Education (OISE) have released a study that identifies systemic challenges in Nunavut’s child welfare system – and recommends strategies to strengthen caregiver support.

Available in Inuktitut and English, the study is one of the first to directly engage caregivers in Nunavut and emphasizes the importance of understanding of Inuit culture. It found that difficulties in information sharing, resource insecurities, caregiver exploitation and institutional harm are critical issues impacting caregivers’ experiences within Family Services.

The study noted that respondents talked about these challenges differently depending on their backgrounds, including race and socioeconomic status. Unlike their settler counterparts, few Inuit caregivers said they felt burnt out or expressed a need for psychological supports – a phenomenon researchers attributed to a profound and deeply personal sense of exhaustion that has cut across generations.

The report’s authors say the findings underscore a critical need for significant reforms in child welfare, including culturally safe support mechanisms for caregivers following disclosures of child maltreatment and abuse.

“Improving caregiver relationships with services could lead to more community members offering to become caregivers, reducing the number of children leaving the territory into the foster care system,” says study co-lead Romani Makkik, a senior researcher at the Umingmak Centre who is Inuk.

The researchers also highlight the importance of respectful engagement with Inuit communities and the equitable provision of resources that acknowledge and address historical and ongoing systemic injustices.

“Families thrive when they receive meaningful information in a culturally safe, timely, and respectful manner," says Jeffrey Ansloos, an associate professor of Indigenous health and social policy at OISE who is Cree and English, and a citizen of Fisher River Cree Nation. “Achieving this requires a fundamental shift in power dynamics and a focus on relational accountability in service delivery, leadership, and research.

“While much work remains to improve child advocacy in Nunavut, Inuit leadership and strong support for Inuit families must be central. This is why Umingmak’s work is so important.”

Caregivers involved in Family Services have long faced unique challenges and a lack of support while navigating child protection processes in Nunavut. For Inuit caregivers, this is exacerbated by the experience of intergenerational trauma, anti-Inuit racism, and the complex history of Family Services and law enforcement complicity in settler colonization across Inuit Nunangat (the Inuit homeland).

In response, the Umingmak Centre opened in Iqaluit in 2019 to provide trauma-informed, culturally safe care for children and families involved in Family Services due to abuse. A critical gap soon emerged: while caregivers sought services for children, they rarely sought support for themselves, despite the distress that child welfare processes may cause – especially for those facing intergenerational trauma, racism or a lack of cultural safety.

To better understand the needs of caregivers and enhance child advocacy, the Umingmak Centre partnered with the Critical Health and Social Action Lab (CHSA Lab) at OISE, an Indigenous-led research centre led by Ansloos that focuses on advancing health justice through community partnerships.

Between October 2022 and July 2023, the research team conducted 30 interviews with Inuit and settler caregivers who had interacted with the Umingmak Centre, as well as Inuit and settler service providers.

Challenging power dynamics in research

One challenging aspect of the project was ensuring the researchers did not replicate the institutional harms they were studying through their own methods, says Cara Samuel, a doctoral candidate at OISE who acted as project co-ordinator for the study.

The team used a collaborative story analysis method for interpreting the interviews. Guided by the principles of Unikkaaqatigiinniq (storytelling) and Iqqaumaqatigiinniq (all knowledge coming into one), the team analyzed interviews in their entirety to preserve the integrity of each individual’s story.

“Often, how we approach research inadvertently reinforces inequitable power dynamics that prioritize Western or Southern knowledge,” says Samuel. “We wanted to elevate Inuit Qauijimajatuqangit (Inuit knowledge) and cultural resources in our research paradigm and centre lived experience.”

Community leadership and partnership

The CHSA Lab’s emphasis on community partnership ensured genuine collaboration and shared decision-making at every stage of the project.

“We were partners, which means equity in leadership and shared responsibilities for the work and its outcomes,” says Samuel.

“Research is only powerful when led by the community it serves, and we were fortunate to work with dedicated partners in Nunavut committed to justice for Inuit families,” adds Ansloos, who is the Canada Research Chair in Indigenous Studies in Health, Suicide Studies, and Environmental Justice. “Our team worked hard to engage a wide range of people, but Umingmak's research leadership, Romani Makkik, and her long-standing relationships and trusted work in the community made our deeper engagement with Inuit caregivers possible.”

Makkik says that the report will play a crucial role in improving Umingmak’s services and shaping future programs – and that the Umingmak Centre hopes to strengthen its partnerships with government services and community organizations to improve services for children and caregivers across Nunavut more broadly.

Soil’s secret language: �山ǿ�� researchers decode plant-to-fungi communication

Christopher.Sorensen — Wed, 13 Nov 2024 21:07:22 +0000

Soil’s secret language: �山ǿ�� researchers decode plant-to-fungi communication

Christopher.Sorensen Wed, 11/13/2024 - 16:07

Cutline

The interaction between fungi and plant hormones could be harnessed to yield hardier crops, reduce fertilizer use and minimize phosphate run-off into waterways, according to a new study by �山ǿ�� researchers (photo by iStock|amenic181)

Neil Macpherson

Topic

Breaking Research

Cell and Systems Biology

Faculty of Arts & Science

Research & Innovation

Subheadline

The discovery could lead to new strategies for cultivating hardier crops and combatting disease-causing fungi

Researchers at the University of Toronto have cracked the code of plant-to-fungi communication.

Using baker’s yeast, the researchers discovered that the plant hormone strigolactone (SL) activates fungal genes and proteins associated with phosphate metabolism, a system that is key to growth.

This insight into how fungi respond to chemical signals at the molecular level – detailed in a new study published in the journal Molecular Cell – could lead to new strategies for cultivating hardier crops and combatting disease-causing fungi.

Shelley Lumba (supplied image)

“As we begin to understand how plants and fungi communicate, we will better understand the complexities of the soil ecosystem, leading to healthier crops and improving our approach to biodiversity,” says Shelley Lumba, lead author and assistant professor in the department of cell and systems biology in �山ǿ��’s Faculty of Arts & Science.

In the soil, plant roots engage with fungi in a silent molecular “language” to direct their structure. When plants release SLs, they signal fungi to attach to their roots, providing phosphates – the fuel plants need to grow, and a major component of most fertilizers – in exchange for carbon.

For the study, Lumba and her fellow researchers investigated why and how fungi respond to SLs. Eighty per cent of plants rely on this symbiotic relationship, and enhancing this interaction with beneficial fungi could yield hardier crops, reduce fertilizer use and minimize phosphate runoff into waterways.

For the study, Lumba and her fellow researchers investigated why and how fungi respond to the plant hormone strigolactone. Illustration: Bradley et al., 2024, Molecular Cell 84, 1–17.

In other cases, disease-causing fungi can exploit chemical cues to infect crops, sometimes wiping out entire harvests. Understanding this chemical language could also help block such pathogens.

The researchers treated baker’s yeast with SLs and observed which genes were turned off and on in response. They found that this chemical signal increased the expression of genes labelled “PHO” that are related to phosphate metabolism. Further analysis showed that SLs function through Pho84, a protein on the surface of yeast that monitors phosphate levels, activating a cascade of other proteins in the phosphate pathway.

The researchers determined that plants release SLs when starved for phosphate, signalling the yeast to change its phosphate uptake.

They found the phosphate response to the SL signal holds true not only for domesticated fungi such as baker’s yeast but also for wild fungi – specifically the detrimental wheat blight Fusarium graminearum and the beneficial symbiotic fungus Serendipita indica.

“Gene expression as an output from chemical treatment is key to this approach – it identifies the effect of the SL response on fungal growth.” says Lumba.

Scientists can use this straightforward method to systematically identify plant-derived small molecules that communicate with fungi. Enhancing the interaction with beneficial fungi could lead to advances in agriculture and mitigate pollution and food insecurity.

“The potential impact of this research can improve the lives of so many,” says Lumba. “It’s about healthy soil for a healthy planet.”

With files from A&S News

Negative body image affects ability to learn and perform physical movements: Study

Christopher.Sorensen — Fri, 08 Nov 2024 15:10:56 +0000

Negative body image affects ability to learn and perform physical movements: Study

Christopher.Sorensen Fri, 11/08/2024 - 10:10

Cutline

The negative impact of body-related embarrassment on movement time was greater among men than women, according to a new study by researchers in �山ǿ��'s Faculty of Kinesiology & Physical Education (photo by Charday Penn/Getty Images)

Jelena Damjanovic

Topic

Breaking Research

Faculty of Kinesiology & Physical Education

Research & Innovation

Subheadline

"We believe this finding could have impacts on learning and life-long participation in sports and physical activity"

Self-consciousness about one’s body has a direct impact on the ability to learn and perform movement tasks, according to a new study by researchers from the University of Toronto’s Faculty of Kinesiology & Physical Education (KPE).

For the study, published in the journal Body Image, participants were asked to recall and write about a time when they felt either proud or embarrassed about their bodies, before completing a movement task.

“Overall, participants in the embarrassed group performed worse than the participants in the proud group, suggesting that evoking negative emotions about the body negatively impacted performance,” says Jude Bek, a post-doctoral fellow who co-authored the study with Professors Catherine Sabiston and Tim Welsh and PhD candidate Delaney Thibodeau.

The researchers also found that the negative impact of embarrassment was stronger among men than women; specifically, re-living body-related embarrassment showed great impact on movement time in men, and on task accuracy in women.

“I was surprised to see a stronger effect of embarrassment in the men, but it is possible that many women already have a heightened sense of body-related embarrassment, so this may have caused them to be less impacted by being asked to recall a time when they felt embarrassed about their body,” says Bek.

Sabiston says she, too, was surprised that embarrassment had a stronger effect in men than women. “For men, the requirement to re-live an embarrassing experience pertaining to their body may have elicited a stronger stress response and therefore greater attention bias that impacted motor performance,” Sabiston says, who holds a Canada Research Chair in Physical Activity and Mental Health

The study builds on previous work by Sabiston and Welsh aimed at testing the impact of body image factors on cognitive and motor performance outcomes. The main foundation of the work is that these emotions lead people to shift attention away from the task at hand to their appearance.

“If they are focused on their body, they are not focused on the task and therefore the performance on the task could be impaired,” says Sabiston, who worked with Welsh on a study that found that tight and revealing clothing negatively impacts motor performance compared to loose, concealing clothing.

“It is interesting to see emotions also having an impact on motor performance – such findings have been commonly observed in cognitive and academic tasks, but this is the first time it was shown in motor performance,” says Welsh. “We believe this finding could have impacts on learning and life-long participation in sports and physical activity.”

Sabiston has carried out several studies that have shown that negative body image is related to drop-out from sports and physical activity due to decreased motivation to participate. She says the sport world is “ripe with body-focused cues and stimuli” ranging from uniform fit and narratives of idealized athletic body types to teammate comparisons and spectator comments.

“Recent public discourse from the Olympics and Paralympic Games also show athletes are often the targets of body-focused stimuli,” she says.

The researchers hope their findings will lead coaches and trainers to reconsider how they provide feedback – if making athletes feel embarrassed leads to decreased performance and learning during training and competition, it might also affect their motivation to stay involved, potentially quelling the benefits of sport participation.

Sabiston says that coaches, parents and guardians are in the best position to make the change in sport culture through thoughtful and intentional communication that doesn’t focus on appearance, but rather on positive role modelling.

“Sport administrators can benefit from designing or allocating uniforms that de-emphasize the body shape and appearance and are comfortable, so they are not a constant focus for athletes,” she says. “Administrators can also reduce appearance-focused media, like posters and print material, in training and performance centres.

“And, athletes can benefit from an awareness of the impact that these body-focused stimuli and cues have on their performance by proactively engaging in stress management and coping strategies such as motivational self-talk, mindfulness and self-compassion practices.”

While these findings have implications for sport skill development and competence, the researchers suggest they may go beyond sport to other important achievement-focused domains such as academics. They also say this study makes clear the need to continue to include men in research focused on body image.

Up next, the researchers intend to delve deeper into the broader implications of negative body image resulting from excessive body scrutiny in sport, including injury risk.

Missing a deadline has a bigger impact than you might think: Study

Christopher.Sorensen — Mon, 04 Nov 2024 15:22:40 +0000

Missing a deadline has a bigger impact than you might think: Study

Christopher.Sorensen Mon, 11/04/2024 - 10:22

Cutline

(photo by Envato Elements)

Alexa Battler

Topic

Breaking Research

Research & Innovation

Rotman School of Management

�山ǿ�� Scarborough

Subheadline

People who were told work was submitted late considered it to be of lower quality than the same work submitted early or on time

Missing a deadline has more complex consequences than you might think.

Researchers at the University of Toronto found that if you submit a piece of work late, people will think it’s lower in quality than if you were to submit the exact same work on time or early.

This is because missing a deadline can prompt others view you as less competent – and therefore your work must also be lacking, according to the study.

“All the research that we could find looked at how deadlines impact the minds and actions of workers,” says study co-author Sam Maglio, a professor of marketing in the department of management at �山ǿ�� Scarborough and the Rotman School of Management.

“We wanted to know how a deadline impacts the minds and actions of others when they look at those workers.”

Researchers surveyed thousands of people in the U.S. and U.K. across 18 experiments and studies, including managers, executives, human resources personnel and others whose jobs included evaluating others.

They presented participants with the same examples of work, including advertising flyers, art, business proposals, product pitches, photography and news articles – and then asked them to rate it. But first, they mentioned whether it was either submitted early, right at the deadline or late. Respondents who were told it was late consistently rated the work as worse in quality than those who were told the same work was early or on time.

“Everyone saw the exact same art contest entry, school submission or business proposal, but they couldn't help but use their knowledge of when it came in to guide their evaluation of how good it was,” says Maglio, who co-authored the study with alumnus David Fang.

The study, published in Organizational Behavior and Human Decision Processes, also finds there isn’t much benefit to submitting work early since evaluators tended to rank work submitted before and at the deadline as the same quality, meaning there’s no boost in an evaluator’s opinion of an employee who submits work early.

Late submission made evaluators rate work about as negatively as work that had objective shortcomings in quality such as not meeting a word count. Furthermore, it didn't matter how late the work was submitted. Work submitted one week after the deadline caused both the employee and the work to be viewed just as negatively as work that was one day late. That remained the case if the employee gave their manager advance warning that they would miss the deadline. Even for an employee with a history of getting their work in on time, one missed deadline still damaged their competence and integrity in evaluators’ eyes.

A missed deadline also led evaluators to believe an employee had less integrity, and they reported they’d be less likely to ask that employee to do other tasks in the future. The researchers note this could limit an employee’s opportunities to prove themselves and earn promotions.

However, the reason behind the missed deadline mattered, researchers found. If it was due to forces beyond an employee’s control, such as jury duty, evaluators didn’t end up with as negative a view of the employee or their work as they did when the reason was one within their control. Researchers also found the negative effects weren’t as severe if the deadline or work were framed as not particularly important.

“Communication around deadlines is vital. If it's a hard, and not a soft, deadline, you as the manager should let your employees know. If the reason why you missed the deadline was beyond your control, you as the employee should let your manager know,” Maglio says. “That seems to be one of the few instances in which people cut you a break.”

The results persisted across language, age and culture. A field experiment was conducted in a high school in China that had students grade pieces of art in a staged contest. The art was on a piece of paper that also included the date it was submitted, showing that one version came in after the deadline and the other was in early. Even though the kids were explicitly told to ignore all other details on the paper other than the art itself, the version submitted after the deadline received lower grades.

“That study breaks down the power imbalance that usually characterizes boss-employee relationships. These judging kids didn’t set the deadline. This is a peer-to-peer evaluation. But the effect holds,” Maglio says. “It also makes the broader point that it doesn't really matter who set the deadline. In the eyes of the evaluator, any miss is a meaningful miss.”

From AI to Atari: What it's like to work with Nobel Prize-winner Geoffrey Hinton

mattimar — Fri, 25 Oct 2024 14:13:56 +0000

From AI to Atari: What it's like to work with Nobel Prize-winner Geoffrey Hinton

mattimar Fri, 10/25/2024 - 10:13

Cutline

From left: Chris Maddison, Nick Frosst and Kevin Swersky at a recent event celebrating �山ǿ�� University Professor Emeritus Geoffrey Hinton's 2024 Nobel Prize in Physics (photo by Johnny Guatto)

Mariam Matti

Topic

Our Community

Alumni

Artificial Intelligence

Computer Science

Faculty of Arts & Science

Geoffrey Hinton

Nobel Prize

Statistical Sciences

Subheadline

Three former students who worked with the "godfather of AI" recall his passionate and playful approach to research

In the wake of Geoffrey Hinton’s 2024 Nobel Prize in Physics, former students and colleagues from the University of Toronto are sharing their favourite anecdotes about the “godfather of AI” – including one involving the classic Atari video game Asteroids.

Nick Frosst (photo by Nina Haikara)

Nick Frosst, a �山ǿ�� alumnus and co-founder of generative AI startup Cohere, said Hinton, University Professor Emeritus of computer science, once spoke of an intense, button-mashing session that left him with nerve damage.

“This kind of explains, perhaps, the way in which he types, which is still two fingers at a time,” said Frosst, who began working with Hinton as a �山ǿ�� undergraduate student and was his first employee at Google Brain.

He shared the story at a recent event hosted by the department of computer science in the Faculty of Arts & Science, saying it offered a telling glimpse into Hinton’s character.

“It’s that fever-pitched intensity, passion and playfulness that he brings to everything … He found something that was fun and engaging and he played it until it damaged a finger and then he continued to push for it.”

Frosst said he also appreciates Hinton’s thoughtful consideration about the potential negative consequences of the revolutionary technology he helped create and praised him for looking past formal qualifications to spot potential and creativity.

“I don't have a master's degree or a PhD, but he was willing to work with me and I saw that in the types of people he brought into Google Brain to work with him,” Frosst said.

“He took lots of chances on people and gave them the time of day once they were there. And for that, I'll always be thankful and deeply privileged, and honoured, to have him in my life.”

Other former students at �山ǿ�� tell similar stories.

Chris Maddison (supplied image)

Chris Maddison, now an assistant professor in �山ǿ��’s departments of computer science and statistical sciences in the Faculty of Arts & Science, was also an undergraduate student when he started working with Hinton in 2011.

He also painted a picture of Hinton’s vibrant office – where everyone knew when he had a new idea.

“The excitement, the joy radiated out of his office down the hall. The air was buzzing with possibility,” said Maddison. “He was famous for bursting into a room and pronouncing that, he now finally, after all these years, understood how the brain worked.”

Kevin Swersky (photo by Johnny Guatto)

Kevin Swersky, a research scientist at Google DeepMind, worked with Hinton as a graduate student at �山ǿ�� and similarly described visiting Hinton as a memorable academic experience.

“Normally when you go to a supervisor's office, you give them a progress update. You go through what your latest results are, you talk about a couple of your ideas and you get some feedback,” he said.

“Going to Geoff’s office was a completely different story. He would be telling you what his latest idea was. He would show you his latest results. And his whole thing was just that he was really excited about it, and his hope was to inspire you enough to start running with it.”

He added that he was particularly inspired by Hinton’s focus on small, solvable puzzles that would ultimately lead to significant breakthroughs over time.

“Geoff would think completely intuitively – like the universe was a puzzle and he was just kind of figuring out where all the pieces went, and the math would always follow whatever he was talking about,” he said.

He also remarked on Hinton’s kindness.

“He offered to put me up for a few weeks,” he said of a time when he found himself looking for a place to stay in Toronto. “He offered to go and get dishes. I was thinking to myself, ‘Wow, Geoff Hinton wants to go out shopping for dishes for me so that I can be comfortable for a few weeks.’”

Geoffrey Hinton shakes hand at a recent �山ǿ�� event celebrating his Nobel Prize (photo by Mac Pattanasuttinont)

Frosst, too, has a Hinton home-making story: the AI luminary built him a desk from scratch.

“He's a carpenter,” Frosst said. “It’s a small wooden desk that fits in the corner of my room at home.

“That's where I keep my computer and work from.”

�山ǿ�� experts use machine learning to analyze where bike lanes should be located for maximum benefit

Christopher.Sorensen — Wed, 23 Oct 2024 14:07:11 +0000

�山ǿ�� experts use machine learning to analyze where bike lanes should be located for maximum benefit

Christopher.Sorensen Wed, 10/23/2024 - 10:07

Cutline

Researchers from �山ǿ��'s Faculty of Applied Science & Engineering used novel computing approaches to compare utilitarian and equity-driven approaches toward expansion of protected bike lanes (photo by Michelle Mengsu Chang/Toronto Star via Getty Images)

Tyler Irving

Topic

Breaking Research

department of mechanical and industrial engineering

Artificial Intelligence

Cities

Faculty of Applied Science & Engineering

Sustainability

Subheadline

“If you optimize for equity, you get a map that is more spread out and less concentrated in the downtown areas"

A team of researchers from the department of civil and mineral engineering in the University of Toronto’s Faculty of Applied Science & Engineering are wielding machine learning to understand where cycling infrastructure should be located in order to benefit the most people.

In a paper published in the Journal of Transport Geography, researchers used novel computing approaches to compare two strategies for expansion of protected bike lanes – using Toronto as a model.

“Right now, some people have really good access to protected biking infrastructure: they can bike to work, to the grocery store or to entertainment venues,” says post-doctoral fellow and lead author Madeleine Bonsma-Fisher, who previously researched interactions between bacteria and viruses before applying her data analysis skills to active transportation. “More lanes could increase the number of destinations they can reach, and previous work shows that will increase the number of cycle trips taken.

“However, many people have little or no access to protected cycling infrastructure at all, limiting their ability to get around. This raises a question: is it better to maximize the number of connected destinations and potential trips overall, or is it more important to focus on maximizing the number of people who can benefit from access to the network?”

To delve into the question, Bonsma-Fisher and co-authors used machine learning and optimization, a challenge that required them to explore new computational approaches.

“This kind of optimization problem is what’s called an ‘NP-hard’ problem, which means that the computing power needed to solve it scales very quickly along with the size of the network,” says Shoshanna Saxe¸ associate professor in the department of civil and mineral engineering and one of Bonsma-Fisher’s two co-supervisors alongside Professor Timothy Chan of the department of mechanical and industrial engineering. “If you used a traditional optimization algorithm on a city the size of Toronto, everything would just crash.”

To get around the problem, PhD student Bo Lin invented a machine learning model capable of considering millions of combinations of over a thousand different infrastructure projects in order to test where the most impactful places are to build new cycling infrastructure.

Using Toronto as a stand-in for any large, automobile-oriented North American city, the team generated maps of future bike lane networks along major streets, optimized according to two broad types of strategies.

The first strategy, dubbed the utilitarian approach, focused on maximizing the number of trips that could be taken using only routes with protected bike lanes in under 30 minutes – without regard for who those trips were taken by.

The second, an equity-based strategy, sought to maximize the number of people who had at least some connection to the network.

“If you optimize for equity, you get a map that is more spread out and less concentrated in the downtown areas,” says Bonsma-Fisher. “You do get more parts of the city that have a minimum of accessibility by bike, but you also get a somewhat smaller overall gain in average accessibility.”

This results in a trade-off, says Saxe. “This trade-off is temporary, assuming we will eventually have a full cycling network across the city, but it is meaningful for how we do things in the meantime and could last a long time given ongoing challenges to building cycling infrastructure.”

Another key finding was that certain routes appeared to be essential no matter what strategy was pursued – for example, protected bike lanes along Bloor Street West.

“Those bike lanes benefit even people who don’t live near them and are a critical trunk to maximizing both the equity and utility of the bike network. Their impact is so consistent across models that it challenges the idea that bike lanes are a local issue, affecting only the people close by,” Saxe says. “Optimized infrastructure repeatedly turns out in our model to serve neighbourhoods quite a distance away.”

The team is already sharing their data with Toronto’s city planners to help inform ongoing decisions about infrastructure investments. Going forward, the researchers hope to apply their analysis to other cities as well.

“No matter what your local issues or what choices you end up making, it’s really important to have a clear understanding of what goals you are aiming for and check if you are meeting them,” says Bonsma-Fisher.

“This kind of analysis can provide an evidence-based, data-driven approach to answering these tough questions.”

�山ǿ�� receives $52 million to upgrade SciNet supercomputer

Christopher.Sorensen — Tue, 22 Oct 2024 15:54:56 +0000

�山ǿ�� receives $52 million to upgrade SciNet supercomputer

Christopher.Sorensen Tue, 10/22/2024 - 11:54

Cutline

From left: Charmaine Dean, Timothy Chan, Bryan May, Nolan Quinn, George Ross, Bardish Chagger, Ranil Sonnadara and Eleanor McMahon (supplied image)

Adam Elliott Segal

Topic

Our Community

SciNet

Artificial Intelligence

Faculty of Applied Science & Engineering

Research & Innovation

Subheadline

The upgraded supercomputer, housed at �山ǿ�� and available to researchers across Canada, will boast roughly three times the computing power of its predecessor

The University of Toronto will receive more than $52 million to upgrade one of the fastest supercomputers in Canada – a shared resource housed at �山ǿ�� that allows researchers across the country to address key challenges in areas such as health care, drug discovery, sustainable transportation, AI and advanced manufacturing.

In a recent announcement, the Digital Research Alliance of Canada – a non-profit organization funded by the Canadian government – and the Government of Ontario committed to investing more than $95 million into advanced research computing (ARC) in Ontario at host sites at �山ǿ�� and the University of Waterloo.

The more than $52 million earmarked for �山ǿ��’s SciNet – which includes matching funds from the province and Compute Ontario – will go toward replacing the Niagara supercomputer with a new computer network with roughly three times the raw computing power, more GPU capacity and storage boosted by an estimated 80 per cent.

“This computational infrastructure is critical for our community and for the Canadian research community at large – from the biomedical sciences to aerospace manufacturing,” said Timothy Chan, �山ǿ��’s associate vice-president and vice-provost, strategic initiatives and a professor in the department of mechanical and industrial engineering in the Faculty of Applied Science & Engineering.

“It supports research in all fields, plus users benefit from the extensive education and training programming offered by SciNet.”

He added that the investment supports Canada’s desire to lead in advanced technologies, and that it comes on the heels of �山ǿ�� University Professor Emeritus Geoffrey Hinton being awarded the 2024 Nobel Prize in Physics for laying the foundations for today’s AI boom through his seminal work on deep learning.

“By expanding Canada’s supercomputing capabilities, we ensure that the country continues to excel in science and research while staying competitive on the global stage,” François-Phillipe Champagne, Canada’s minister of innovation, science and industry, said in a statement.

Chan, for his part, said the shared computing infrastructure, which will utilize a more sustainable, state-of-the-art cooling system, is a savvy use of public funding.

“These investments result in cost savings,” he said. “Ontario’s publicly funded ARC ecosystem costs users 80 per cent less than commercial cloud systems.”

He said students and researchers across Canada should be encouraged by the news.

“It's a unique resource,” he said. “If my students are doing computational research, they can use the cloud, which is expensive. Or they can build their own computer to do it, but they’re not going to have the same kind of power, scale or expert support as something like SciNet.

“It plays a big role in being able to speed up research, speed up discovery with whatever they're working on and access more computational memory, more storage and more computational power.”

For example, Chan says students can run an algorithm at much faster speeds and test multiple algorithms at the same time – something that’s not always possible on local machines.

“Equipping the next generation with job-ready skills in high-performance computing, machine learning and AI is critical to industries including manufacturing, automotive, finance, and the life sciences. When we invest in advanced research computing, we help our students get skilled jobs and attract highly skilled workers to Ontario.”

Researchers uncover new role for cell’s waste disposal system in spread of pancreatic cancer

Christopher.Sorensen — Tue, 22 Oct 2024 14:02:57 +0000

Researchers uncover new role for cell’s waste disposal system in spread of pancreatic cancer

Christopher.Sorensen Tue, 10/22/2024 - 10:02

Cutline

Associate Professor Leonardo Salmena, post-doctoral researcher Golam Saffi and former master’s student Lydio To investigated the role of a gene called INPP4B in pancreatic cancer’s ability to spread (supplied images)

Betty Zou

Topic

Breaking Research

Princess Margaret Cancer Centre

Temerty Faculty of Medicine

Cancer

Research & Innovation

University Health Network

A preclinical study is revealing new insights into the molecular machinery that drives the aggressiveness of pancreatic cancer.

The ability of pancreatic cancer to invade and spread to other parts of the body is a major factor in its poor prognosis, with an overall five-year survival rate of less than 10 per cent.

“Pancreatic cancer cells are known to be very metastatic and that’s a big problem,” says Leonardo Salmena, an associate professor of pharmacology and toxicology in the University of Toronto’s Temerty Faculty of Medicine.

Salmena is the senior author of a study, published in the Journal of Cell Biology, that investigates the role of a gene called INPP4B in pancreatic cancer’s ability to spread. Led by post-doctoral researcher Golam Saffi and former master’s student Lydia To, the team found that INPP4B exerts its tumour-promoting effects via a cellular organ called the lysosome.

“Classically, the lysosome is a garbage disposal organelle where old and tired proteins and other organelles get degraded to be used for energy and other building blocks for the cell,” says Salmena.

In most cells, lysosomes typically cluster around the nucleus. But in pancreatic cancer cells, the researchers found that INPP4B drove the lysosomes from the cell interior to the periphery, where these organelles fuse with the cell’s outer membrane. In doing so, the enzymes and other lysosomal factors responsible for breaking down cellular waste are dumped into the space surrounding the tumour cells.

This space contains a network of proteins and molecules that provides crucial structural support to cells and tissues while also restricting a cell’s ability to move. The release of the lysosome’s protein-degrading contents into this extracellular space causes the stabilizing network to fall apart, thus making it easier for pancreatic cancer cells to migrate and invade other tissues.

Crucially, Salmena and his team also identified the signalling pathway by which INPP4B drives the movement of lysosomes to the cell edge. INPP4B works with two other proteins – PIKfyve and TRPML-1 – to modify the lysosome’s surface structure and alter local calcium levels so that the organelle is propelled to the cell periphery.

Based on these findings, the researchers are testing two experimental drugs that target TRPML-1 and PIKfyve in a preclinical model of pancreatic cancer. They are also studying how the release of lysosomal contents can change the immunological environment of the cancer cells, and what effects that might have on the immune system’s ability to respond to the tumour.

Salmena first became interested in INPP4B when, during his post-doctoral research, he found that it was involved in breast cancer. Since then, he and his team have shown that the effects of INPP4B vary depending on the context.

For example, in some breast cancer types, INPP4B behaves as a tumour suppressor whereas it has an activating role in other aggressive cancers like pancreatic cancer – which the Canadian Cancer Society expects to be the third leading cause of cancer death in Canada in 2024, with an estimated 6,100 people dying from the disease.

Salmena and his colleagues later showed that among all cancers, INPP4B levels are highest in pancreatic tumours, and that high levels of the protein are associated with decreased overall survival in people with pancreatic cancer.

The study was a collaboration between Salmena’s group, Roberto Botelho, a professor of chemistry and biology at Toronto Metropolitan University, and Steven Gallinger, a hepatobiliary and pancreatic surgical oncologist and clinician-scientist at Princess Margaret Cancer Centre, University Health Network and a professor of surgery and laboratory medicine and pathobiology in Temerty Medicine. He is also director of the PanCuRx Translational Research Initiative at the Ontario Institute for Cancer Research.

The study was supported by the Cancer Research Society and the Canadian Institutes of Health Research.

Large-scale adoption of electric vehicles can lead to human health benefits: Study

Christopher.Sorensen — Mon, 21 Oct 2024 14:05:14 +0000

Large-scale adoption of electric vehicles can lead to human health benefits: Study

Christopher.Sorensen Mon, 10/21/2024 - 10:05

Cutline

Researchers from �山ǿ��'s Faculty of Applied Science & Engineering used computer models to simulate the impact of large-scale adoption of electric vehicles in the U.S. (photo by: Plexi Images/Glasshouse Images/UCG/Universal Images Group via Getty Images)

Tyler Irving

Topic

Breaking Research

Faculty of Applied Science & Engineering

Research & Innovation

Sustainability

Subheadline

"Our simulation shows that the cumulative public health benefits of large-scale EV adoption between now and 2050 could run into the hundreds of billions of dollars"

Large-scale adoption of electric vehicles (EVs) could lead to significant health benefits for populations, according to a new study from the department of civil and mineral engineering in the University of Toronto’s Faculty of Applied Science & Engineering.

Researchers used computer simulations to show that aggressive electrification of the U.S. vehicle fleet, coupled with an ambitious roll-out of renewable electricity generation, could result in health benefits worth between US$84 billion and 188 billion by 2050.

Even scenarios with less aggressive grid decarbonization mostly predicted health benefits running into the tens of billions of dollars.

“When researchers examine the impacts of EVs, they typically focus on climate change in the form of mitigating CO2 emissions,” says Professor Marianne Hatzopoulou, one of the co-authors of the study, which was published in PNAS.

“But CO2 is not the only thing that comes out of the tailpipe of an internal combustion vehicle. They produce many air pollutants that have a significant, quantifiable impact on public health. Furthermore, evidence shows that those impacts are disproportionately felt by populations that are low-income, racialized or marginalized.”

The research team previously used their expertise in life-cycle assessment to build computer models that simulated the impact of large-scale EV adoption in the U.S. market.

Among other things, they showed that while EV adoption will have a positive impact on climate change, it is not sufficient on its own to meet the Paris Agreement targets. They recommended that EV adoption be used in combination with other strategies, such as investments in public transit, active transportation and higher housing density.

In their latest study, the team sought to account for the non-climate benefits of EV adoption. They adapted their models to simulate the production of air pollutants that are common in fossil fuel combustion, such as nitrogen oxides, sulphur oxides and small particles known as PM2.5.

“Modelling these pollutants is very different from modelling CO2, which lasts for decades and ends up well-mixed throughout the atmosphere,” says study co-author Daniel Posen, an associate professor in the department of civil and mineral engineering.

“In contrast, these pollutants, and their associated health impacts, are more localized. It matters not only how much we are emitting, but also where we emit them.”

While EVs do not produce tailpipe emissions, they can still be responsible for air pollution if the power plants that supply them run on fossil fuels. This also has the effect of displacing air pollution from busy highways to the communities that live near those power plants.

Another complication is that neither the air pollution from the power grid nor that from internal combustion vehicles is expected to stay constant over time.

“Today’s gasoline-powered cars produce a lot less pollution than those that were built 20 years ago, many of which are still on the road,” says Jean Schmitt, post-doctoral fellow and lead author of the study.

“So, if we want to fairly compare EVs to internal combustion vehicles, we have to account for the fact that air pollution will still go down as these older vehicles get replaced. We can also see that the power grid is getting greener over time, as more renewable generation gets installed.”

The team, which also included Professor Heather MacLean of the department of civil and mineral engineering and Amir F. N. Abdul-Manan of Saudi Aramco’s Strategic Transport Analysis Team, chose two primary scenarios to simulate to the year 2050. In the first, they assumed that no more EVs will be built, but that older internal combustion vehicles will continue to be replaced with newer, more efficient ones.

In the second scenario, they assumed that by 2035, all new vehicles sold will be electric. The researchers described this as “aggressive,” but it is in line with the stated intentions of many countries. For example, Norway plans to eliminate sales of non-electric vehicles next year, and Canada plans to follow suit by 2035.

For each of these scenarios, they also considered various rates for the transition of the electric grid to low-emitting and renewable energy sources.

Under each set of conditions, the team simulated air pollution levels across the U.S. and used calculations commonly used by epidemiologists, actuaries and policy analysts to correlate pollution levels with statistical estimates of the number of years of life lost, as well as with estimates of economic value.

“Our simulation shows that the cumulative public health benefits of large-scale EV adoption between now and 2050 could run into the hundreds of billions of dollars,” says Posen.

“That’s significant, but another thing we found is that we only get these benefits if the grid continues to get greener. We are already transitioning away from fossil fuel power generation, and it’s likely to continue in the future. But for the sake of argument, we modelled what would happen if we artificially freeze the grid in its current state.

“In that case, we’d actually be better off simply replacing our old internal combustion vehicles with new ones – but again, this is not a very realistic scenario.”

This finding raises the question of whether it’s more important to decarbonize the transportation sector through EV adoption, or to first decarbonize the power generation sector that’s the ultimate source of pollution associated with EVs.

To that, Hatzopoulou notes that vehicles sold today will continue to be used for decades. “If we buy more internal combustion vehicles now, however efficient they may be, we will be locking ourselves into those tailpipe emissions for years to come, and they will spread that pollution everywhere there are roads,” she says. “We still need to decarbonize the power generation system – and we are – but we should not wait until that process is complete to get more EVs on the road.

“We need to start on the path to a healthier future today.”