Division of Natural Sciences

Climate change is transforming how scientists think about their roles

Rachel Sauer — Fri, 18 Apr 2025 15:08:35 +0000

Climate change is transforming how scientists think about their roles Rachel Sauer Fri, 04/18/2025 - 09:08

Sarah Kuta

91��ý researcher Pedro DiNezio emphasizes solving the problems of climate change in the here and now

When Pedro DiNezio began studying El Niño and La Niña roughly 20 years ago, human-caused climate change was still a future problem. At that time, researchers spent much of their energy trying to show that humans were, in fact, influencing the world’s climate.

Flash forward two decades, and climate change is no longer some far-off, eventual phenomenon—it’s happening now. Communities and businesses are factoring climate change into their yearly, monthly and even weekly decisions.

Against this backdrop, climate scientists are starting to transition away from purely theoretical research and pivot toward more applied work and consulting. DiNezio, a University of Colorado Boulder associate professor of atmospheric and oceanic sciences, for example, is embarking on a new partnership with WTW, a global insurance broker and risk advisor—an exciting prospect for putting research into practice.

“We can’t stop the drought and the heatwaves, but we can do things to become more resilient, so they don’t affect us as badly—at least for a while,” says Pedro DiNezio, a 91��ý associate professor of atmospheric and oceanic science.

“I’m going through a career transformation right now because I’m more and more interested in solving problems in the here and now,” says DiNezio. “Because we now know so much about the climate system and about the impact it could have on society, many of us in academia are feeling that it’s time to act.”

Resilience is key

As global temperatures continue to rise, world leaders are taking steps to reduce greenhouse gas emissions. Whether their actions will be enough to stave off catastrophic warming remains to be seen. But, in the meantime, communities and businesses must prepare for and adapt to the unprecedented extremes caused by climate change.

Drought, heatwaves, wildfires, rising sea levels, coastal erosion and other ripple effects are already causing big problems—and scientists like DiNezio might be able to help solve them.

“We can’t stop the drought and the heatwaves, but we can do things to become more resilient, so they don’t affect us as badly—at least for a while,” DiNezio says. “And hopefully we can win that time we need to stabilize the climate.”

For example, research has linked hot weather with an increased risk of accidents and injuries in the workplace. Employees are more likely to suffer heat-related illnesses on hot days. But they’re also more likely to be involved with other seemingly unrelated accidents, too.

From an ethical perspective, companies want to keep their workers safe and healthy. But, from a business perspective, they also want to keep costs down—and workers-compensation insurance is a major expense.

“We’re only starting to learn the full extent of the impact of heatwaves and how we can mitigate them,” says DiNezio. “This is having a huge impact on businesses. So, how do we prevent these accidents?”

As the climate shifts, supply chains are also becoming increasingly vulnerable. When vital waterways like the Panama Canal’s Gatun Lake dry up during droughts, ships cannot reach their intended destinations on time. And those delays cost money.

“You cannot avoid these things, but at least you can know there’s a risk and plan an alternative shipping route,” DiNezio says.

Reinsurance companies are particularly interested in anticipating disasters because they already take a long-term, big-picture view of risk. While a company in one part of the world might be worried about drought and another might be focused on sea level rise, global reinsurance companies see what’s happening around the world and connect the dots.

“Reinsurance companies look for our knowledge because their scale makes them more sensitive to the aggregated effect of climate change over large swaths of the world,” says DiNezio. “They are some of the first businesses to think, ‘How do we anticipate this new climate that is continually changing and prepare for it?’”

Why now?

Climate science is a relatively new field. But, in recent years, it’s matured enough to allow researchers to make predictions that are applicable to communities and businesses.

When vital waterways like the Panama Canal’s Gatun Lake (above) dry up during droughts, ships cannot reach their intended destinations on time. And those delays cost money. (Photo: Valiant/Shutterstock)

“We are starting to see these climate events happening, we have the tools to better predict them, and the climate sector is recognizing this as a problem, as a need,” says DiNezio. “As academics, we cannot ignore them because this is no longer a theoretical exercise.”

Teaching has played an important role in DiNezio’s transformation. After joining the 91��ý faculty four years ago, DiNezio began teaching an introductory-level class on climate change for non-science majors.

Every semester, DiNezio updated the curriculum because the climate was changing so fast. That process has been a bit of a reality check.

“When you talk about it with students, especially non-science majors, they are interested in what effect this could have on their lives and their careers,” says DiNezio. “You have to think about these things more concretely.”

Concrete problems

DiNezio, like other climate scientists who are experimenting with consulting, is approaching this new career chapter with a mix of enthusiasm and anticipation.

“I’m diving into something that I haven’t done before,” DiNezio says. “Sometimes, I describe it to my friend like I’m doing another PhD. … A lot of people in my field are going through this transformation and is entirely new.”

But, in some ways, DiNezio suspects solving real-world problems may be easier than solving theoretical ones. Either way, DiNezio is looking forward to the new challenge.

“When you move away from the purely academic, the problems become really concrete,” DiNezio says. “It’s really simple: How do you prevent heat deaths or help farmers mitigate drought? For me, the new thing is the action. The transformation is, how do we act with all this information about weather and climate? It’s very different from the academic approach. Now, we have a goal.”

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91��ý researcher Pedro DiNezio emphasizes solving the problems of climate change in the here and now.

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Don’t fear the fungi

Rachel Sauer — Thu, 17 Apr 2025 13:30:00 +0000

Don’t fear the fungi Rachel Sauer Thu, 04/17/2025 - 07:30

Bradley Worrell

91��ý mycologist Alisha Quandt says there’s little reason to fear a fungi-zombie apocalypse like the one imagined in the HBO hit TV series ‘The Last of Us’

Alisha Quandt prepared herself in advance to be asked by students and others about Sunday’s season 2 premier of “The Last of Us”—the hit HBO series that imagines a post-apocalyptic future where a fungal infection on a massive scale turns the majority of humanity into zombie-like creatures seeking to infect the last pockets of civilization.

It’s not that Quandt is a super-fan of the TV show (“I’m not into zombies, honestly,” she confesses), but as a mycologist—a scientist who studies fungi—she is used to getting asked about the TV show, specifically whether the grim future it imagines is anything people need to be worried about, or whether it’s simply harmless entertainment.

“I’m happy if it gets people excited about fungi. They’re so incredible,” says Alisha Quandt, a 91��ý assistant professor of ecology and evolutionary biology.

“Especially when the TV show first debuted, it was definitely a topic people wanted to discuss,” says Quandt, a University of Colorado Boulder Department of Ecology and Evolutionary Biology assistant professor.

“And it seems like the topic (of infectious fungi) comes up in popular culture every five to 10 years. When I was starting my PhD, people were fascinated by the ‘Planet Earth’ TV series by David Attenborough, where this ant infected by Ophiocordyceps unilateralis staggers around, being controlled by the fungus. Then later, the Last of Us videogame came out, which really got people excited about (zombie) fungi.”

Quandt did her PhD research studying Cordyceps-like fungi, which is the type of pestilence the TV show identifies as the culprit for turning civilization into a hellscape populated by zombies controlled by the spiky fungi tendrils sprouting from their heads. For the record, Quandt finds that scenario very unlikely, for a variety of reasons.

No need to panic

For starters, the TV show imagines a worldwide outbreak is caused by Cordyceps-contaminated food. However, Quandt says most fungal infections in humans are caused by inhaling spores or through contact with the eyes or skin—and not through the digestive tract. She notes that in many parts of the world, people have been ingesting Cordyceps fungi for decades without incident, because they believe they contain beneficial properties.

“I’ve eaten Cordyceps in Asia, in Korea and China,” says Quandt, who remains unzombified. “It’s considered a part of traditional Chinese medicine, especially certain species. Even here in the U.S., you can find Cordyceps in coffees and teas, for example. They sell them at stores in Boulder.”

Quandt says another reason not to be overly concerned about Cordyceps is that many of them are “specialists” that have a very narrow range of hosts that they infect, down to a specific family of ant or spider. While some Cordyceps can transition from infecting one type of arthropod to another, or to jump from infecting an insect to another fungus, she says making the leap to a healthy human being is remote.

What’s more, the average human body temperature of 97 to 99 degrees Fahrenheit is not an environment that’s hospitable for many fungi, although Quandt acknowledges there are exceptions. “The Last of Us” imagines a future in which global warming has raised Earth temperatures to a point where mutated Cordyceps zombie fungi could live comfortably in human hosts, but Quandt notes that ambient temperatures of even 90 degrees Fahrenheit are still cooler than the human body.

“That’s a hard path for me to follow,” she says of an environmental change that would allow Cordyceps to evolve in such a way. “There’s a lot of assumptions that would go into that trajectory.”

91��ý scientist Alisha Quandt finds the scenario from "The Last of Us" in which a Cordyceps-like fungi causes worldwide zombification very unlikely, for a variety of reasons. (Photo: HBO)

Beyond those arguments, Quandt says there is an even more important one as to why humans don’t need to start doom prepping for a fungi apocalypse.

“My argument about why we shouldn’t be worried about a fungal pandemic is that our bodies, when fully immunocompetent—meaning healthy human bodies—are extremely well equipped to deal with fungal propagules (spores) that come into contact with our bodies, mostly through our lungs,” she says. “Fungi have this cell wall that is made up of stuff that our bodies do not make. So, our bodies are really good identifying and dealing with that.”

Quant says fungal infections do pose a risk to people whose immune systems are compromised—particularly if they have taken a heavy dose of antibiotics, because those can kill off good bacteria, which can lower resistance to harmful fungi.

“Once our immune system goes away, which could handle those types of (fungi), we have so few antifungal drugs to treat fungal infections compared to the myriad of antibiotics that we have to treat bacterial diseases,” she says.

For the immunocompromised, Quandt says one of the most concerning fungi—which just cropped up in recent years and has spread worldwide—is Candida auris.

“It is a really concerning human pathogen because it is what we call nosocomial, meaning it is hospital related. People get these infections in hospitals, and once it’s in a hospital, it can be almost impossible to get rid of it,” she says.

“People will use all kinds of bleach and ethanol but it’s very hard to get rid of the yeast once it gets into a hospital room. And the fully immunocompetent, like nurses and doctors who are not sick, can end up spreading it from room to room to sick, often elderly, patients. Unfortunately, there’s not a good defense on the ground, so to speak, once Candida auris takes hold.”

But while “opportunistic pathogens” like Candida auris can pose a risk to the immunocompromised, the number of fungal diseases that could be described as “primary pathogens”—meaning they can infect and potentially cause serious health issues for healthy individuals—is less than a handful, Quandt says.

One primary pathogen that can be found in the United State is Valley Fever, which is primarily located in New Mexico, Arizona and southern California. Farming, construction or other practices that disrupt the soil can release the fungi’s spores, which people can then breathe into their lungs. Once inhaled, Valley Fever can potentially cause fever, cough, tiredness, shortness of breath and, in limited cases, serious conditions such as pneumonia and meningitis.

“But those are the rarer things, and I’m still not worried about them becoming common because they’re still not being spread from person to person,” she says.

In contrast with the way “The Last of Us” portrays fungi as an existential threat, Quandt sees a type of virus that’s already well-known to the scientific community and the public alike as a much greater risk for causing a global pandemic. The World Health Organization estimates the COVID-19 pandemic killed 14.9 million people worldwide between January 2020 and December 2021.

“As we’ve recently seen, unfortunately, there are a lot of other places to look for more likely suspects for (global pandemics). Things that were predicted by a lot of great investigative journalists and epidemiologists, like coronavirus and other zoonotic diseases (which jump from animals to humans), pose a much greater threat to mankind,” she says.

“As we’ve recently seen, unfortunately, there are a lot of other places to look for more likely suspects for (global pandemics). Things that were predicted by a lot of great investigative journalists and epidemiologists, like coronavirus and other zoonotic diseases (which jump from animals to humans), pose a much greater threat to mankind.”

And now, back to the show

Even beyond the fact she’s not into zombies, Quandt says her training as a mycologist can get in the way of her enjoyment of “The Last of Us” as entertainment, based upon the few episodes she has watched.

“I’m probably a little too close to watch the show—especially the fruiting bodies,” she says. “Sometimes they would show a person who is dead up against a wall, and the fruiting structures look life shelf fungi,” she says.

“Those are related to mushrooms—they’re not related to (fungi) that are molds, like Cordyceps. The artistry was beautiful, so they did a good job visually, but it’s just completely inaccurate. So, it does take you out of it a little bit to watch as an expert; you have to really suspend belief.”

Another scene that inspired disbelief for Quandt was a flashback episode—prior to the fungal pandemic—when a mycologist in Jakarta is asked by representatives of the country’s military to provide guidance on how to proceed after a group of workers in a building are found to be infected with early cases of the Cordyceps contagion. After surveying the infected, the mycologist gives the military members a chilling one-word answer: “Bomb!” (As in, bomb the entire country to try to prevent the infection from spreading.)

“My husband was watching the show with me. He paused it there and he’s like, ‘What should they do?’ I was like, ‘Get all the antifungals that you can. Get all the major ones and then get the rare ones—and start pumping these people with IVs, or all the people that you think might be exposed and get going on it.’ But the fact she said ‘bomb!’ I almost found it funny, but I was also like, ‘Oh, my God, that’s so dramatic.’ Still, it’s a TV show, and I acknowledge that.”

While Quandt may opt not to watch more episodes of “The Last of Us,” she says if the TV show raises public awareness about fungi—even if the details in the show are not entirely correct—she is all for it.

“I’m happy if it gets people excited about fungi,” she says. “They’re so incredible.”

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91��ý mycologist Alisha Quandt says there’s little reason to fear a fungi-zombie apocalypse like the one imagined in the HBO hit TV series ‘The Last of Us.'

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Top image: HBO

CU grad Erin Macdonald makes it so

Rachel Sauer — Tue, 15 Apr 2025 22:18:50 +0000

CU grad Erin Macdonald makes it so Rachel Sauer Tue, 04/15/2025 - 16:18

Bradley Worrell

The 2009 math and astrophysics double major has successfully transformed herself from a scientist to an educator to a storyteller sailing with the enterprise known as Star Trek

As she worked toward completing her bachelor’s degrees in astrophysics and mathematics at the University of Colorado Boulder in the late 2000s, Erin Macdonald often enjoyed watching Star Trek: The Next Generation with her college friends. Today, she is a science advisor for the entire Star Trek franchise.

“I don’t think I could have ever conceived it, that being able to work in television and movies was a real thing that people could actually do,” Macdonald says in retrospect. “And if you told me that I would see my name in TV credits—not to mention in the Star Trek font with the Star Trek theme playing—it’s almost unbelievable.”

It’s been a remarkable journey from academia to Hollywood, Macdonald acknowledges. Still, she is quick to add that in a multiverse of possibilities, the outcome was never assured, and it did not happen at warp speed.

91��ý alumnus Erin Macdonald, who double majored in mathematics and astrophysics, is a science advisor for the Star Trek franchise and author of Star Trek: My First Book of Space. (Photo: Bradley Worrell)

Raised in Fort Collins, Colorado, Macdonald did not grow up watching Star Trek. However, she was deeply motivated to study science after being inspired by the protagonist astronomer Ellie Arroway in the movie Contact, as well as by fictional FBI agent and medical doctor Dana Scully in the popular TV show The X-Files.

“I watched The X-Files growing up, and Dana Scully for me was just the coolest woman who ever existed. That really sparked an excitement to be a scientist,” she says. “And then when Contact came out, watching Dr. Ellie Arroway use a telescope to find aliens, and seeing her legitimately work as an astronomer was the first time I ever saw that as a career.”

Still, there were some obstacles to overcome, Macdonald says, including the fact that math did not come naturally to her.

“In high school, I had friends who were taking classes that seemed to get it. And for me, I felt like I was trudging through mud trying to understand things—but knowing that I had to get through the math,” she says. Finally, when taking a Calculus 3 course at 91��ý, she says she experienced a breakthrough when she came to understand how math worked with physics, and then “everything just clicked.” It prompted her to immediately declare a double major in mathematics and astrophysics.

Gaining another role model

It also was in college that Macdonald was first exposed to Star Trek through a tightknit group of fellow students who were big fans of the TV shows.

“In the Venn diagram of physics majors and Star Trek fans, there is a big intersection,” she says with a laugh. “I was in my early 20s and (fictional) Voyager Captain Catherine Janeway became my new Scully. She was someone who had gone from being a science officer to a captain. At that point, I knew I wanted to get my PhD, but I didn’t necessarily want to be a researcher as a career. So, Janeway was a role model, how she was a leader and a problem-solver and a mentor. It was something I aspired to.”

After graduating from 91��ý in May 2009, Macdonald enrolled at the University of Glasgow in Scotland, where she earned her PhD in astrophysics in 2012. Normally, a master’s degree would be the next educational step after obtaining an undergraduate degree, but Macdonald credits the quality of the education she received at 91��ý—and particularly the research opportunity and mentorship of astrophysics and planetary sciences Professor Jeremy Darling—with allowing her to immediately advance to working toward a doctorate.

After obtaining her PhD, Macdonald spent two years doing post-doctoral research at Cardiff University in Wales, United Kingdom. She later moved back to Colorado, where she worked as an adjunct professor in the community college system and as an educator at the Denver Museum of Nature & Science for about a year, then transitioned to work as an aerospace engineer for a contractor based in the Denver area.

“In the Venn diagram of physics majors and Star Trek fans, there is a big intersection,” says 91��ý alumnus Erin Macdonald. (Photo: Bradley Worrell)

It was during her time working for the contractor, and while attending pop culture conventions for fun, that Macdonald hit upon the idea that she could combine her deep knowledge of astrophysics with her love of science fiction to give talks on the science of science fiction TV shows, movies and videogames at fan conventions.

“After a while in the private sector, I found I really missed teaching. I was already going to conventions, so I proposed giving talks,” she says, adding that event organizers were receptive to the idea. “For topics, a popular one is physics and Star Trek. I’d say, ‘I did my PhD in gravitational physics, so let me explain how (theoretically) warp drives work, because I actually know the science of how warp drives work.’”

To boldly go …

In 2017, Macdonald moved to the Los Angeles area, where she continued to work in the aerospace industry while also giving science/science fiction talks at fan conventions, or as she describes herself in that time: “rocket scientist by day, warp engineering expert by evening.” It was during that period that she began meeting actors and writers at fan events, which ultimately led to industry connections with executives at CBS, the producer of all things Star Trek.

Macdonald was initially hired to give talks at CBS-sponsored events, including Star Trek Cruises. That led to an introduction with the co-executive producer of Star Trek Discovery, who asked Macdonald to serve as a science advisor for the show as season 3 began production.

“I believe I did a good job on that season, so I think the executives saw value in hiring a science advisor to be available to all of their shows to maintain consistency across the franchise, to understand all of the made-up technologies that we have in Star Trek and to be able to communicate that to the writers as well,” she says. “That’s been going on since 2019, so almost five years now.”

Meanwhile, Macdonald has written four screenplays, and she has done voice acting for Star Trek Prodigy, an animated Star Trek show, during which she had the opportunity to work with Kate Mulgrew, the actress who played Captain Janeway on Star Trek Voyager.

“When I started working on Star Trek Prodigy, they were bringing Captain Janeway back as a teacher for young kids. I was going to help write some of her lines, and that was when I had this huge epiphany of—I’m not meant to become Captain Janeway; I’m meant to write Captain Janeway and create characters that inspire kids to become scientists,”

“When I started working on Star Trek Prodigy, they were bringing Captain Janeway back as a teacher for young kids. I was going to help write some of her lines, and that was when I had this huge epiphany of—I’m not meant to become Captain Janeway; I’m meant to write Captain Janeway and create characters that inspire kids to become scientists,” she says. “And so now, I find that storytelling lets me sort of inspire and motivate the next generation of STEM professionals, and that’s what I want to do as a career.”

Macdonald has found her voice as a storyteller in several different ways. In 2022, she published Star Trek: My First Book of Space, an illustrate children’s board book that uses Star Trek to talk about science, technology, engineering, arts and math (STEAM), and she wrote and narrated the Audible Original “The Science of Sci-Fi” in collaboration with The Great Courses.

Additionally, in 2021, McDonald created Spacetime Productions, a film development and production company devoted to giving representation to traditionally marginalized voices, including those in the LGBTQIA+ community. The company has produced two short films including Identiteaze, released on the streaming service Nebula earlier this summer.

Reflecting on her journey from scientist to educator to storyteller, Macdonald says her success is the result of recognizing good opportunities, trusting her instincts, perseverance and, most importantly, putting in the time and work to achieve her goals.

“You know, I didn’t quit my PhD and move to LA with no plan. I took those important steps in between,” she says. “And it took me until well into my 30s for me to realize what I wanted, to be a storyteller and create those Dana Scullys and Captain Janeways, as opposed to becoming one of those characters. And that’s OK. All of those steps along the way helped inform the work I do now.”

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The 2009 math and astrophysics double major has successfully transformed herself from a scientist to an educator to a storyteller sailing with the enterprise known as 'Star Trek.'

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Professor John Cumalat wins 2025 Hazel Barnes Prize

Rachel Sauer — Fri, 11 Apr 2025 22:19:58 +0000

Professor John Cumalat wins 2025 Hazel Barnes Prize Rachel Sauer Fri, 04/11/2025 - 16:19

Cumalat ‘literally re-shaped our understanding of the fundamental particles making up the known universe,’ colleagues note

John Cumalat, professor of distinction in the University of Colorado Boulder Department of Physics, has been awarded the 2025 Hazel Barnes Prize.

Established in 1991 by former chancellor James Corbridge to honor the late Hazel Barnes, 91��ý professor of philosophy from 1953-86, the $20,000 Hazel Barnes Prize celebrates the enriching interrelationship between teaching and research and is the largest and most prestigious award funded by the university.

“Professor Cumalat is an exemplary educator and researcher whose contributions to his students, this university and the field of physics are highly deserving of recognition,” said Chancellor Justin Schwartz. “His selection as the Hazel Barnes Prize winner reflects his dedication and ingenuity, and I am so proud of all the ways he utilizes these qualities in service to 91��ý and to humanity.”

Cumalat completed his PhD in physics from the University of California Santa Barbara in 1977 and his postdoctoral work with Fermilab in Batavia, Illinois, in 1979. Since joining the 91��ý physics faculty in 1981, he has garnered multiple honors, including the Best Should Teach Award in 2003, the Robert L. Stearns Award in 2010 and the BFA Excellence in Service Award in 2013. He became a professor of distinction in 2014.

“John is an educator in the broadest sense and has had a lasting impact on his students and colleagues. He leads by example, he leads from the front, and he leads with integrity and compassion.”

Best known for his research in particle physics and for his development of state-of-the-art particle-detector technology and instrumentation, Cumalat is a member of five professional organizations: Sigma Xi, the American Association for the Advancement of Science, the American Association of Physics Teachers, the American Astronomical Society and the American Physical Society.

He is also a member of the Compact Muon Solenoid experiment at the Large Hadron Collider at CERN, the current principal investigator of the CU High Energy Physics Department of Energy Grant and the principal investigator of the Professional Research Experience Program with the National Institute of Standards and Technology.

Cumalat has authored or co-authored more than 1,500 publications and has been cited nearly 200,000 times, according to INSPIRE, an online hub that collects scholarly work in the field of high-energy physics. He has also served on several dozen graduate-student committees and on approximately 150 undergraduate-student thesis committees.

In their letters supporting Cumalat’s nomination for the Hazel Barnes Prize, several of his colleagues noted the significance of his contributions to the field of physics.

“John Cumalat has literally re-shaped our understanding of the fundamental particles making up the known universe,” wrote 91��ý Professor of Physics James Nagle. “His research focuses on the fundamental building blocks of matter and his leadership has led to critical advances in our understanding of quarks as well as the discovery of the Higgs boson.”

“John is one of the very best physicists that I know,” said Joel Butler, a distinguished scientist at Fermilab. “He is well-known and greatly respected throughout the U.S. and in the world. I consider it one of the most fortunate aspects of my own career that I have had this long and productive association with him.”

Other colleagues brought attention to Cumalat’s role in expanding and improving physics education at 91��ý.

“John’s leadership was critical in the expansion of the number of physics degrees in the College of Arts and Sciences,” said 91��ý Professor of Physics Paul D. Beale. “I believe that John’s most important and lasting contribution to teaching and learning is his leadership in expanding the number of physics students engaged in undergraduate research, especially conducting honors research projects with members of the physics faculty and other scientists and engineers.”

“John is an educator in the broadest sense and has had a lasting impact on his students and colleagues,” said Patricia Rankin, former physics professor at 91��ý and current chair of the Physics Department at Arizona State University. “He leads by example, he leads from the front, and he leads with integrity and compassion.”

“I am honored to be selected by previous Hazel Barnes winners as the 2025 Hazel Barnes Prize winner,” says Cumalat. “I particularly value my colleagues in physics nominating me for the award and for soliciting external supporting letters from students and national and international colleagues. I am humbled by the entire process.”

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Cumalat ‘literally re-shaped our understanding of the fundamental particles making up the known universe,’ colleagues note.

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CU alum Stephen Koehler enjoys high-flying career

Rachel Sauer — Wed, 09 Apr 2025 18:14:40 +0000

CU alum Stephen Koehler enjoys high-flying career Rachel Sauer Wed, 04/09/2025 - 12:14

Bradley Worrell

The ROTC cadet and physics major turned naval aviator turned admiral was appointed commander of the U.S. Pacific Fleet in early 2024

University of Colorado Boulder grad Stephen T. Koehler (Phys’86) has a really, really big job.

How big?

It covers an area encompassing 100 million square miles—roughly half the earth’s surface—from Antarctica to the Artic Circle and from the western U.S. coast to the Indian Ocean. The job includes oversight of about 200 ships, 1,500 aircraft and 150,000 military and civilian personnel.

91��ý grad and U.S. Navy Admiral Stephen Koehler (Phys’86) was selected as the commander of the U.S. Pacific Fleet in April 2024, following a succession of leadership positions in the Navy.

Admiral Koehler is the commander of the U.S. Pacific Fleet, a position he assumed in April 2024 after a series of successive leadership positions during his 40-year career in the Navy. He became the 36th commander since Admiral Chester Nimitz assumed command on Dec. 31, 1941, at Pearl Harbor.

Koehler’s ascension to a top leadership post in the Navy is perhaps even more notable given that his initial goal was modest: He wanted to fly jets like his dad, who was a Navy fighter pilot.

“Honestly, I didn’t know I would stay in the Navy this long,” he says. “But from a very young age, I watched my dad go to work to fly airplanes and I just thought he was so cool, and I remember thinking, ‘I want to do what he does.’ My dad loved being a fighter pilot. So, I knew I wanted to fly jets and land them on ships.”

After being commissioned in 1986 through the Naval Reserve Officers’ Training Corps (ROTC) program at 91��ý, Koehler became a naval aviator in 1989 and went on to fly more than 3,900 hours in the F-14 Tomcat and F-18 Hornet, with 600 carrier landings.

Koehler subsequently served in leadership positions that included commanding a fighter squadron, serving as the captain of a nuclear aircraft carrier, commander of a carrier strike group, commander of the U.S. Third Fleet and director for strategy, plans and policy for the Joint Staff in Washington, D.C., which was his last post.

Recently, Koehler spoke with Colorado Arts and Sciences Magazine about how his time at 91��ý helped him prepare for his career in the Navy, what it was like to be a naval aviator and what his job entails as commander of the U.S. Pacific Fleet. His responses have been lightly edited and condensed for space.

Question: Why did you decide to attend 91��ý? And why did you choose to get your degree in physics?

Koehler: The main reason I ended up applying to 91��ý was that the summer before my senior year in high school, I was taking a Greyhound bus around the country, rock climbing with my cousin. We stopped in Boulder for a week and we stayed with this guy who was a friend-of-a-friend type thing. We climbed nearly every day.

One day it rained bad enough we couldn’t climb, so we heard there was a campus in town and we decided maybe we should walk around it. I picked up an application at the UMC (University Memorial Center), where it stayed in my backpack for the rest of the summer. Later, I filled it out and sent it in, and then I got accepted.

I saw CU had a physics major and it had ROTC, so I said, ‘I’ll give it a go.’

Admiral Stephen Koehler (right) with his father, who was also a naval aviator, following the younger Koehler’s commissioning in 1986 during a ceremony held at Old Main on the 91��ý campus.

I knew I wanted to be as competitive as I could going into Navy flight school. And initially, I thought I might want to be a test pilot—and I knew you had to have hard-science capability for that, so that’s why I majored in physics. I was not a natural physics guy, so it was a slog for me, but I did it to keep my options open.

Question: Do you feel like your time at 91��ý helped prepare you for entering the Navy?

Koehler: Yes. Certainly, the ROTC piece provided an understanding of the Navy even beyond what I learned as a child of a Navy parent, and it taught me about leadership.

The physics background proved very beneficial, not only for flight school, but it led to me being selected to be a nuclear-trained officer. There is a technical degree that’s required to do that, and so, yes, my time at CU set me up for that.

Question: When people think of naval aviators, they likely think of the movie Top Gun. What is it like to be a naval aviator in real life?

Koehler: People who watch Top Gun think you are all tan and spend your days playing volleyball at the beach, or they watch Top Gun: Maverick and think you’re all tan and you play football on the beach (laughs). And arguably, I would love to do some of that, but being a carrier-based fighter pilot is about being steeped in professionalism.

Naval aviators train and train so that they make the extremely difficult look easy and routine when it’s not. It takes skill to land a plane on a pitching (ship) deck, day or night, and it takes dedication to be a fighter pilot, to make sure that you are better than the adversary. It’s about having a warrior mindset and making sure you are good at it, because you’ve got to be better than your opponent.

Question: What is your call sign and how did you get it?

Koehler: It’s Web. I won’t go into the whole boring story, but it’s short for Webster’s Dictionary. I received it during a very public display for a lack of spelling prowess (laughs). And I’m actually not a bad speller, but I was on that day.

I wish it (the call sign) was for something cool, like ‘spiderweb,’ or ‘he’s on the web.’ That’s probably half the reason it stuck—because it sounds cool even though it’s not (laughs). …

Now, even at this level, people call me by that name instead of my (given) name. I was sitting in the situation room in the White House in my last job and people would call me Web—not Steve or Admiral Koehler. They would be like, ‘Hey, Web, what do you think about this?’ So, that’s just what ends up happening.

Question: How does one go from being a naval aviator to a command where you are responsible for hundreds of ships and planes and tens of thousands of sailors?

Koehler: So, it’s a process. The first step of it is staying in the Navy and being promoted to the command of a squadron, which is 12 planes and about 250 people. You’re evaluated and then there’s normally two paths after that. You either go the nuclear power route, which means you learn to drive aircraft carriers, or you stay in the air wing and you’re in command of an air wing on a carrier.

The U.S. Pacific Fleet (a portion of which is pictured here) encompasses 100 million square miles from Antarctica to the Arctic circle and from the west coast of the United States into the Indian Ocean. The U.S. Pacific Fleet consists of approximately 200 ships, 1,500 aircraft and 150,000 military and civilian personnel. (Photo: U.S. Navy)

I was chosen to go the nuclear power route, so my physics degree proved useful. I went to nuclear power school and then I was the No. 2 guy on an aircraft carrier, the USS Carl Vinson. I went on to command the USS Bataan, which is an amphibious assault ship, and then I was selected to be the captain of a nuclear aircraft carrier for two and a half years, which was the USS Dwight D. Eisenhower.

Pending your performance and time in service, you may be selected to the rank of rear admiral (or flag rank). If you are not selected, there’s mandatory retirement at 30 years.

I was selected after my command of the aircraft carrier and have progressed through operational and staff command that yielded additional flag rank promotions. There was a decision by Naval leadership at some point to promote me to full admiral and select me to be the Pacific Fleet commander. So, it was a natural progression, and I’m very honored to be here.

Question: Can you share the scope of your duties as Pacific Fleet commander and the role the position plays in the world today?

Koehler: The scope and scale of the Pacific Fleet, of the area I’m responsible for as far as naval interests, is from the coast of California to the west coast of India, and Antarctica to the Arctic. It’s a huge area. …

The Pacific Fleet command is of vital importance to national security, resulting from the economic ties and the commerce that travels on the ocean, for which I am responsible on the Navy side to be ready to respond. There’s just a real importance to the job and there’s a lot of work to do out there. We must continue to improve our position and capability to maintain and ensure the freedom of the seas. The intent is a ‘free and open Indo-Pacific,’ with freedom of commerce, sovereign rights and the ability to sail and operate in accordance with international law, and those things the Pacific Fleet works continuously to provide.

Question: What is the best thing about being Pacific Fleet commander? And what is the most difficult thing?

Koehler: The best thing is having the opportunity to lead all of these sailors. With sailors and civilians, there is on the order of 150,000 of them working toward a common goal, which is to achieve our national objectives. The opportunity to go out and see them and lead them is the best. That also delves into the challenge, which is that it’s a large scale and scope of operations that I oversee. The challenge is to be able to get out and see them as much as I would like and revel in the success they have. They are a pretty amazing group of people who do some outstanding work.

Admiral Stephen Koehler salutes during a 2024 ceremony at Pearl Harbor. (Photo: U.S. Navy)

Question: Do you still get to fly jets?

Koehler: I wish I did. I did get to fly as an admiral when I was the carrier strike group commander and we were on deployment in 2017. I got my last carrier landing in April of 2018.

Flying is a young person’s game. Not that I wouldn’t continue to go flying … but there’s no time to maintain my currency and while it would be fun for me, I’m not sure it would be the best use of my time now.

Question: With your four decades of service in the Navy, are there a few standout moments in your career?

Koehler: That’s a really hard one. First of all, it’s been 40 years, but it doesn’t seem like it. I got to Colorado (as a freshman) in 1982, and it feels like I was just there. …

There are all sorts of things I remember. Taking command of an aircraft carrier, with 3,000 people assigned to it, and with the air wing it’s 5,000 people. That was the first huge command for me, and you have all of these sailors that you get the privilege to lead.

Certainly, the news that I was going to be Pacific Fleet commander was memorable. That was something I would never expect. It’s the honor of a lifetime to do that, and to follow in the footsteps of some amazing people, starting with Admiral Nimitz in World War II.

Another standout thing was being the demonstration pilot for the F-14 at air shows and having the opportunity to fly in front of my family at the Miramar Air Show in 1996. It was an amazing day to fly for my dad that day.

Looking back, there are many memories, and it’s been nothing but a really fun, challenging, rewarding experience. I have been able to enjoy it with my wife, Gina, who’s been with me since college, where we met in 1983 in Boulder in the Baker Hall dorm. She’s been with me the whole time, which has just been amazing.

Question: Anything else you would like to add?

Koehler: Go Buffs!

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The ROTC cadet and physics major turned naval aviator turned admiral was appointed commander of the U.S. Pacific Fleet in early 2024.

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Top image: Admiral Stephen Koehler (green flight suit) was designated a naval aviator in 1989 and flew more than 3,900 hours in the F-14 Tomcat and F-18 Hornet, with 600 carrier landings.

Who has the influence to curb gender bias in STEM?

Rachel Sauer — Tue, 25 Mar 2025 13:30:00 +0000

Who has the influence to curb gender bias in STEM? Rachel Sauer Tue, 03/25/2025 - 07:30

Cody DeBos

Hint: It’s not women

When Charlotte Moser started graduate school, she was the only woman in a shared office with four male students. One day, a classmate casually remarked that he wished she weren’t there so the office could be all men.

Moser barely had time to process the sting of the exclusion before another male student cut in, calling out the remark as gender bias.

“It felt so great to have someone stand up for me,” Moser recalls. “I felt like someone had my back and I belonged in this space.”

Charlotte Moser, a research associate in 91��ý’s Department of Psychology and Neuroscience, studies how allyship in male-dominated fields influences workplace culture.

That moment stayed with her—not just because of the personal validation, but because it led her to begin exploring a larger pattern in workplace dynamics.

Now as a research associate in the University of Colorado Boulder’s Department of Psychology and Neuroscience, Moser studies how allyship in male-dominated fields influences workplace culture. Her findings reveal an unsettling but potentially useful truth: When men openly advocate for gender equality, their voices often carry more weight than women’s do.

The reason? Not necessarily gender, Moser says, but power and influence.

The social influence gap

Moser’s research suggests that in STEM workplaces, where men hold most leadership positions, male allies are perceived as more persuasive, more legitimate and more effective at creating a culture that supports gender equality than their female counterparts.

“We find that men who advocate for gender equality and act as allies tend to be better at signaling to women that they will belong and be respected in male-dominated STEM contexts than when women advocate for gender equality,” Moser says.

Her findings suggest that allyship in male-dominated workplaces isn’t just about intent or even gender. Rather, it’s about who is perceived as having the power to create change.

If a female scientist points out that women are often overlooked for leadership roles or promotions, she may be met with skepticism or dismissed as self-interested. But when a male colleague makes the same argument, research shows that their remark is more likely to be taken seriously and perceived as a norm-setting statement rather than a personal complaint.

“Other work has found that men tend to be perceived more positively than women when advocating for gender equality,” Moser explains. “Women tend to be viewed as whiners, complainers, and only acting in their own self-interest.”

The cost of exclusion

Gender bias in the workplace isn’t a theoretical issue. It has real repercussions.

Car-crash dummies designed to represent women’s bodies weren’t introduced until 2011. Even today, they are tested only in the passenger seat, not the driver’s seat. (Photo: Lin Pan/Wikimedia Commons)

“A huge consequence is the loss of the contributions from many brilliant women scientists,” Moser says.

Research shows that women are less likely to be retained in male-dominated fields due to factors like persistent bias, exclusion and a lack of support. With fewer women present to offer their perspective, blind spots emerge, and those gaps can have serious, even deadly, implications.

One striking example is the case of crash-test dummies.

“For decades, car-crash dummies were built to represent the average body of a man,” Moser says. “This led women to be much more likely to fall victim to serious injury and death in car crashes.”

Shockingly, car-crash dummies designed to represent women’s bodies weren’t introduced until 2011. Even today, they are tested only in the passenger seat, not the driver’s seat. Recent statistics show that women are 17% more likely to be killed in a car accident and 73% more likely to be seriously injured than male occupants.

This oversight isn’t an accident, but the denouement of decades of scientific decision-making that lacked diverse perspectives.

“More inclusive science is better for everyone—not just those who face bias,” Moser says.

Going beyond performative allyship

If allyship from men is perceived as more effective, what should they do to ensure their support is genuine and impactful?

Moser has a few recommendations.

“I would say that men who don’t know where to start could start within their own spheres. Pay attention to what’s going on, how people are treated, and listen to the women around you,” she says.

But listening is only the first step.

Moser emphasizes that standing up against gender bias isn’t just about making statements on social media or in private. Meaningful allyship requires action.

Calling out dismissive remarks in a team meeting or challenging biased hiring decisions can have an immediate effect. Those in leadership positions can stretch their influence further by advocating for equitable organizational policies and ensuring women have access to mentorship and career-advancement opportunities.

“One hurdle for men regarding allyship for gender equality is that they feel that it is ‘not their place,’” Moser says. “I hope that my work can show that allyship from men is not only wanted but very beneficial to women.”

However, Moser warns that inauthentic allyship—publicly claiming to support gender equality without backing it up—can make meaningful change even harder to achieve.

“The future of allyship isn’t just about who speaks. It’s about who gets listened to.”

“I have other work showing that it is worse to claim allyship but then do nothing to promote equality than if one had said nothing about inequality and allyship in the first place,” she says.

Who deserves to be heard?

Moser’s research makes clear the fact that eliminating gender bias in the workplace isn’t a matter of men versus women. Rather, it’s about recognizing and altering the systems that create credibility and influence.

“I think allyship can change the narrative of the widespread belief that most men don’t care about women and change the narrative that it’s women’s responsibility to make these workplaces work for them,” she says.

But the goal isn’t just getting men to use their influence—it’s about redistributing power so that women’s voices carry the same weight without needing male validation.

“The future of allyship isn’t just about who speaks,” Moser explains. “It’s about who gets listened to.”

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Hint: It’s not women.

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Discovering Boulder County’s tiniest residents

Rachel Sauer — Mon, 24 Mar 2025 17:10:47 +0000

Discovering Boulder County’s tiniest residents Rachel Sauer Mon, 03/24/2025 - 11:10

Collette Mace

91��ý alum and experienced caver Dave Steinmann recently discovered a new species of pseudoscorpion in Mallory Cave, with a moniker honoring its namesake hometown

When Dave Steinmann (Phys’90) first started classes at the University of Colorado Boulder in 1984, he had never explored a cave before and never really thought much about caves. However, when his new dorm-mate suggested they try his dad’s favorite hobby of caving, what seemed at first like an adventurous new pastime soon turned into a lifestyle for Steinmann—one that he has continued for more than 30 years and leading to his discovery of almost 100 new cave-dwelling species.

Steinmann, now a research associate with the Denver Museum of Nature & Science’s Zoology Department, most recently discovered a new species of pseudoscorpion named after the city closest to where it was found—none other than CU’s hometown of Boulder. Steinmann said that he knew almost immediately that the critter that is now known as Larca boulderica was a new species.

Dave Steinmann (right) with his son, Nathan (left), and wife, Debbie (center), as they get ready to go caving. (Photo: Dave Steinmann)

When he first spotted it in Mallory Cave, one of Boulder’s most well-known cave systems thanks to its role in bat conservation, he immediately noticed its unique, almost lentil-shaped body and adaptations for cave living, such as its pale color. These specimens were later verified as a new species by Mark Harvey, a pseudoscorpion expert at the Western Australian Museum; Harvey and Steinmann recently published details of the discovery in ZooKeys.

Steinmann notes that it’s typically not difficult to discern when a specimen is a new species, as it happens pretty frequently in the ancient cave systems right below our feet.

“I always say that if I want to discover a new species, I just need to visit a new cave,” he says.

Why are caves such a great place to make new discoveries? The answer lies in their role as a sort of refuge from climate change, Steinmann notes. In caves, insects can hide from the effects of temperature, floral and faunal changes that happen more rapidly in the outside world, facilitating isolated evolutionary changes.

Changing cave life

However, even cave life is changing. Lately, the temperature inside of caves, typically very cold, has been observed to be rising on a minuscule scale. Although this may seem trivial, even a few degrees’ difference can have immeasurable effects on the delicate life structures within the caves.

Similarly, outside temperatures affect which species go in and out of the cave systems, most notably bats. With the recent spike in white-nosed syndrome in bat populations, the number of bats in cave systems has decreased dramatically, with disastrous effects on internal cave species such as Larca boulderica, who survive on organic material—most often wood brought into the cave—and guano (bat fecal matter).

These changes are slow to progress, though, and there is still time to save cave ecosystems like that of Mallory Cave, which is closed to the public to protect the bat population inside (although it’s still possible to hike up to the cave entrance, a pleasant and short hike for anyone hoping to get outside).

So, how did Steinmann spot these teeny tiny bugs who live on bat feces? Well, after more than 30 years of experience, he has some tricks up his sleeve. One of the easiest methods he uses to spot tiny critters is simply by turning over rocks or pieces of wood.

When species like pseudoscorpions are disturbed by the movement or sense the carbon dioxide released by human breathing, they tend to skitter in every direction, looking for a new spot to curl up and revel in the damp darkness. When they move around, according to Steinmann, it’s just a game of whether you can catch them quickly enough.

The newly described pseudoscorpion Larca boulderica is about the size of a sesame seed and is only known to live in Boulder, Colorado. (Photo: Dave Steinmann)

To catch samples, Steinmann usually brings simple tools along with him—a painter’s brush and some rubbing alcohol. When the brush is wetted with the alcohol, it’s easy to run it along a surface and pick up all of the tiny things residing there, including minuscule species of bugs like Larca boulderica.

From there, it’s also easier to see what he’s found, as cave species are usually albino due to the lack of melanin— they don’t need pigmentation when there’s no sunlight—and they stand out against the dark ground and hairs of the paintbrush.

Looking for a gold bug

Despite being at it for multiple decades, Steinmann has no plans to slow down his caving career any time soon. He’s even made it a family pastime, and often spends time caving with his wife, Debbie, and his son, Nathan. He keeps an ongoing list of caves he plans to visit in the future and looks forward to making even more discoveries.

“I’d really like to find some kind of gold-colored bug and name it after the university,” he says, “or maybe even Coach Prime!”

He’s also enthusiastic about getting more students involved in caving, including caver and photographer Andres “Andy” Better, who will be a CU transfer student next fall. Steinmann emphasized how many different opportunities lie in the caving experience and says students of any background could find a niche interest in the hobby.

He also mentions local groups and clubs for both new and experienced cavers, including the Front Range Grotto and the Colorado Grotto, which meets at the Colorado School of Mines. He says that while anyone is welcome in caving, experienced members of the clubs can sometimes be protective of the places they visit, as human disturbances can harm delicate cave ecosystems, and caving as a hobby can be dangerous in a lot of ways.

However, if you’re looking to learn about caving with curiosity and respect, any of these clubs are great ways to get involved in this adventurous and exciting hobby—just be careful not to step in the bat guano because there could be a new species in there!

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91��ý alum and experienced caver Dave Steinmann recently discovered a new species of pseudoscorpion in Mallory Cave, with a moniker honoring its namesake hometown.

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An ultrafast microscope makes movies one femtosecond at a time

Rachel Sauer — Tue, 11 Mar 2025 16:18:01 +0000

An ultrafast microscope makes movies one femtosecond at a time Rachel Sauer Tue, 03/11/2025 - 10:18

New 91��ý research harnesses the power of an ultrafast microscope to study molecular movement in space and time

The interactions in photovoltaic materials that convert light into electricity happens in femtoseconds. How fast is that? One femtosecond is a quadrillionth of a second. To put that in perspective, the difference between a second and a femtosecond is comparable to the difference between the second right now and 32 million years ago.

Subatomic particles like electrons move within atoms, and atoms move within molecules, in femtoseconds. This speed has long presented challenges for researchers working to make more efficient, cost-effective and sustainable photovoltaic materials, including solar cells. Imaging materials on the nanoscale with high enough spatial resolution to uncover the fundamental physical processes poses an additional challenge.

Understanding how, where and when electrons move, and how their movement depends on the molecular structure of these materials, is key to honing them or developing better ones.

Ultrafast nano-imaging of structure and dynamics in a perovskite quantum material also used for photovoltaic applications. Different femtosecond laser pulses are used to excite and measure the material. They are focused to the nanoscale with an ultrasharp metallic tip. The photo-excited electrons and coupled changes of the lattice structure (so called polarons, red ellipses) are diagnosed spectroscopically with simultaneous ultrahigh spatial and temporal resolution. (Illustration: Branden Esses)

Building on more than five years of research developing a unique ultrafast microscope that can make real-time “movies” of electron and molecular motion in materials, a team of University of Colorado Boulder scientists published in Science Advances the results of significant innovations in ultrafast nanoimaging, visualizing matter at its elementary atomic and molecular level.

The research team, led by Markus Raschke, professor of physics and JILA fellow, applied the ultrafast nanoimaging techniques they developed to novel perovskite materials. Perovskites are a family of organic-inorganic hybrid materials that are efficient at converting light to electricity, generally stable and relatively easy to make.

Working with a thin perovskite layer, the researchers directed ultrashort laser pulses onto tiny metallic tips positioned above the perovskite layer. The tip functions like an antenna for the laser light and focuses it to a spot much smaller than what is possible in conventional microscopes. The tip is then scanned across the perovskite layer, creating an image pixel by pixel. Each image provides one frame of a movie as the different laser pulses are varied in time.

The movie also has “color,” albeit in the infrared and invisible to the human eye but where the molecules and electrons respond. Through different wavelengths of light, the researchers can follow both the electron and molecular motion and their coupling, which is what controls the photovoltaic efficiency in perovskites.

This milestone not only helps them better understand the missing links between the perovskite’s crystal structure and composition and its performance as a photovoltaic material but also led to the surprising discovery that more disorder seems to facilitate better photovoltaic performance.

“We like to say that we’re making ultrafast movies,” Raschke says, adding that there have long been many unknowns about the elementary processes after sunlight gets absorbed in photovoltaic materials and how the excited electrons move in them without being dispersed, but “for the first time, we can actually sort this out because we can record spatial, temporal and spectral dimensions simultaneously in this microscope.”

Molecules as spectators of how the electrons move

In recent years, much research has focused on perovskites, particularly in the quest to create more efficient and sustainable solar cells. These materials absorb certain colors of the visible spectrum of sunlight effectively and can be layered with other materials, such as silicon, that catch additional wavelengths of light the perovskite does not absorb.

"This is a way to examine the material properties on a very elementary level, so that in the future we’ll be able to design materials with certain properties in a more directed way."

“(Perovskites) are easy to fabricate and have a very high solar cell efficiency, and can be applied as a very thin film,” explains Roland Wilcken, first author on the new paper and a post-doctoral researcher in Raschke’s research group. “But the problem with this material is it has relatively low photostability.”

Improving the material’s performance is no easy feat. There’s a large possible combination of chemical compositions and preparation conditions of perovskite solar cells, which affect their structure, performance and stability in ways that are difficult to predict. This is a challenge also faced by many other complex materials used for semiconductors, quantum materials, displays or in biomedical applications.

This is where the ultrafast microscope helps the researchers gain the spatial and temporal information needed to optimize the material—and in turn—find a good compromise between stability and performance.

Building the ultrafast microscope was a challenge, explained Branden Esses, a physics graduate student and research contributor. The team used nanotips, coated in a platinum alloy or gold, which are brought within nanometers of the perovskite layer, then hit with a sequence of laser pulses.

The first pulse excites the electrons in the visible, and subsequent pulses in the infrared watch how the electrons and molecules interact and move in time, Esses says, adding that “if you shine a light on this very tiny tip, the light that comes back is very weak since it only interacts with very few electrons or molecules; it’s so weak that you need special techniques to detect it.”

So, they developed a special method, modulating the light beams and using optical-amplification techniques to reduce noise and background to isolate the desired information.

Both how “the light is focused at the nanometer scale with the tips and how it is emitted and detected was essential to get enough contrast and signal to make these ultrafast movies of the material,” Wilcken explains.

And thanks to the ultrafast microscope technology, researchers are able to capture ultra-high-resolution images of femtosecond movement, measuring atomic motion in the molecules with very high precision. A particular feature of this development is the ability to resolve the dynamics of the molecular vibrations as a spectator of how the material responds to the photoexcited electrons.

Building better and functional materials from the bottom up

“This is a way to examine the material properties on a very elementary level, so that in the future we’ll be able to design materials with certain properties in a more directed way,” explains Sean Shaheen, a professor of electrical, computer and energy engineering who provided the material sample and collaborated on the research.

“We’re able to say, ‘We know we prefer this kind of structure, which results in, for example, longer lived electronic excitations as linked to photovoltaic performance,’ and then we’re able to inform our material synthesis partners to help make them,” Esses adds.

One of the surprising results of the work is that “in contrast to conventional semiconductors it seems that more structural disorder gives rise to more stable photogenerated electrons in hybrid perovskites,” Raschke explains. With the ultrafast microscope it became possible for the first time “to directly image the role of molecular order, disorder and local crystallinity on the optical and electronic properties of materials in general.”

This discovery is expected to have a profound impact on material science for advancing the performance of novel semiconductor and quantum materials for computing, energy and medical applications.

The instrument development was supported by the National Science Foundation, through STROBE, an NSF Science and Technology Center for which Raschke serves as co-principal investigator.

Roland Wilcken, Branden Esses, Rachith Nithyananda Kumar, Luaren Hurley, Sean Shaheen and Markus Raschke contributed to this research.

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New 91��ý research harnesses the power of an ultrafast microscope to study molecular movement in space and time.

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Communities working together for better air

Rachel Sauer — Thu, 06 Mar 2025 19:32:50 +0000

Communities working together for better air Rachel Sauer Thu, 03/06/2025 - 12:32

Jenni Shearston

Colorado is tackling air pollution in vulnerable neighborhoods by regulating five air toxics

The Globeville, Elyria-Swansea and Commerce City communities in metro Denver are choked by air pollution from nearby highways, an oil refinery and a Superfund site.

While these neighborhoods have long suffered from air pollution, they’re not the only ones in Colorado.

Now, Colorado is taking a major step to protect people from air pollutants that cause cancer or other major health problems, called “air toxics.” For the first time, the state is developing its own state-level air toxic health standards.

91��ý researcher Jenni Shearston studies chemical exposure and health, measuring and evaluating the impact of air pollution on people’s well-being.

In January 2025 Colorado identified five air toxics as “priority” chemicals: benzene, ethylene oxide, formaldehyde, hexavalent chromium compounds and hydrogen sulfide.

The state is in the process of setting health-based standards that will limit the amount of each chemical allowed in the air. Importantly, the standards will be designed to protect people exposed to the chemicals long term, such as those living near emission sources. Exposure to even low amounts of some chemicals, such as benzene, may lead to cancer.

As a researcher studying chemical exposure and health, I measure and evaluate the impact of air pollution on people’s well-being.

Colorado’s new regulations will draw on expert knowledge and community input to protect people’s health.

Communities know what needs regulation

In your own community, is there a highway that runs near your house or a factory with a bad odor? Maybe a gas station right around the corner? You likely already know many of the places that release air pollution near you.

When state or local regulators work with community members to find out what air pollution sources communities are worried about, the partnership can lead to a system that better serves the public and reduces injustice.

For example, partnerships between community advocates, scientists and regulators in heavily polluted and marginalized neighborhoods in New York and Boston have had big benefits. These partnerships resulted in both better scientific knowledge about how air pollution is connected to asthma and the placement of air monitors in neighborhoods impacted the most.

In Colorado, the process to choose the five priority air toxics included consulting with multiple stakeholders. A technical working group provided input on which five chemicals should be prioritized from the larger list of 477 toxic air contaminants.

The working group includes academics, members of nongovernmental organizations such as the Environmental Defense Fund – local government and regulated industries, such as the American Petroleum Institute.

There were also opportunities for community participation during public meetings.

At public hearings, community groups like GreenLatinos argued that formaldehyde, instead of acrolein, should be one of the prioritized air toxics because it can cause cancer.

Additionally, formaldehyde is emitted in some Colorado communities that are predominantly people of color, according to advocates for those communities. These communities are already disproportionately impacted by high rates of respiratory disease and cancer.

Other members of the community also weighed in.

“One of my patients is a 16-year-old boy who tried to get a summer job working outside, but had to quit because air pollution made his asthma so bad that he could barely breathe,” wrote Logan Harper, a Denver-area family physician and advocate for Healthy Air and Water Colorado.

How is air quality protected?

At the national level, the Clean Air Act requires that six common air pollutants, such as ozone and carbon monoxide, are kept below specific levels. The act also regulates 188 hazardous air pollutants.

Individual states are free to develop their own regulations, and several, including California and Minnesota, already have. States can set standards that are more health-protective than those in place nationally.

Four of the five chemicals prioritized by Colorado are regulated federally. The fifth chemical, hydrogen sulfide, is not included on the U.S. Environmental Protection Agency’s hazardous air pollutant list, but Colorado has decided to regulate it as an air toxic.

State-level regulation is important because states can focus on air toxics specific to their state to make sure that the communities most exposed to air pollution are protected. One way to do this is to place air pollution monitors in the communities experiencing the worst air pollution.

For example, Colorado is placing six new air quality monitors in locations around the state to measure concentrations of the five priority air toxics. It will also use an existing monitor in Grand Junction to measure air toxics. Two of the new monitors, located in Commerce City and La Salle, began operating in January 2024. The remainder will start monitoring the air by July 2025.

When Colorado chose the sites, it prioritized communities that are overly impacted by social and environmental hazards. To do this, officials used indexes like the Colorado EnviroScreen, which combines information about pollution, health and economic factors to identify communities that are overly burdened by hazards.

The Commerce City monitor is located in Adams City, a neighborhood that has some of the worst pollution in the state. The site has air toxics emissions that are worse than 95% of communities in Colorado.

Air toxics and health

The five air toxics that Colorado selected all have negative impacts on health. Four are known to cause cancer.

When state or local regulators work with community members to find out what air pollution sources communities are worried about, the partnership can lead to a system that better serves the public and reduces injustice.

Benzene, perhaps the most well known because of its ability to cause blood cancer, is one. But it also has a number of other health impacts, including dampening the ability of the immune system and impacting the reproductive system by decreasing sperm count. Benzene is in combustion-powered vehicle exhaust and is emitted during oil and gas production and refinement.

Ethylene oxide can cause cancer and irritates the nervous and respiratory systems. Symptoms of long-term exposure can include headaches, sore throat, shortness of breath and others. Ethylene oxide is used to sterilize medical equipment, and as of 2024, it was used by four facilities in Colorado.

Formaldehyde is also a cancer-causing agent, and exposure is associated with asthma in children. This air toxic is used in the manufacture of a number of products like household cleaners and building materials. It is also emitted by oil and gas sources, including during fracking.

Hexavalent chromium compounds can cause several types of cancer, as well as skin and lung diseases such as asthma and rhinitis. A major source of hexavalent chromium is coal-fired power plants, of which Colorado currently has six in operation, though these plants are scheduled to close in the next five years. Other sources of hexavalent chromium include chemical and other manufacturing.

Finally, long-term exposure to hydrogen sulfide can cause low blood pressure, headaches and a range of other symptoms, and has been associated with neurological impacts such as psychological disorders. Some sources of hydrogen sulfide include oil refineries and wastewater treatment plants.

Jenni Shearston is an assistant professor in the Department of Integrative Physiology.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Colorado is tackling air pollution in vulnerable neighborhoods by regulating five air toxics.

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Storytelling, not statistics, can make STEM more inclusive

Rachel Sauer — Tue, 04 Mar 2025 22:57:54 +0000

Storytelling, not statistics, can make STEM more inclusive Rachel Sauer Tue, 03/04/2025 - 15:57

Cody DeBos

91��ý researcher Eva Pietri studies how stories can help address gender bias and create inclusivity

Eva Pietri wasn’t planning on being part of a documentary.

When the University of Colorado Boulder associate professor of psychology and neuroscience was contacted by the creators of Picture a Scientist, a film that takes an unflinching look at sexism and discrimination in STEM (science, technology, engineering and math), she was thrilled to discuss her research. Pietri, who has an extensive background studying gender bias in STEM, knows interventions often fail because facts alone rarely change minds.

But when paired with human narratives, they become undeniable.

“I think one danger with anything that talks about bias is that it might dishearten people. But storytelling, when done right, can motivate people to do something about it," says Eva Pietri, a 91��ý associate professor of psychology and neuroscience.

“They’re doing exactly what I would have recommended,” Pietri recalls thinking as she watched the film engage audiences with compelling stories supported by data.

Now, Pietri’s latest research explores how storytelling can be a powerful tool for shifting perceptions about gender bias and creating more inclusive environments. It supports what filmmakers have long believed—that stories can change culture.

Why facts alone aren’t enough

Traditional diversity training in STEM often follows a familiar formula: workshops, slideshows and statistical breakdowns of workplace disparities. Though well intentioned, such initiatives often fail to change minds.

Facts alone, it turns out, aren’t always enough.

“It’s easy when you hear one story, especially if you aren’t motivated to believe it, to think, ‘Well that was just you,’” Pietri explains. “But if we have some data to back that story up, the combination can be more persuasive.”

Her studies in social psychology reveal that the most effective interventions engage both the rational and emotional centers of the brain. This phenomenon, known as narrative persuasion, happens when people become absorbed in a story.

In short, emotional investment makes us more likely to find a new perspective and reconsider past assumptions.

“Having communications that use both stories and the data can be really powerful. And I think documentaries are a unique platform to do that,” Pietri says.

That’s precisely what makes Picture a Scientist effective. The film follows three women in STEM careers who recount their experiences with bias, harassment and institutional roadblocks. Their stories create an emotional connection, making it difficult for viewers to dismiss sexism as an abstract problem.

A case study in narrative persuasion

When Picture a Scientist arrived in 2020, its timing created an unusual moment. The COVID-19 pandemic had forced companies and universities to rethink their approach to workplace training, including diversity programs.

Traditional workshops, which already struggled to engage audiences, were relegated to Zoom. But the documentary offered a more compelling alternative.

Pietri and her colleagues saw an opportunity.

The filmmakers had already consulted with her during production, but after the film’s release, they proposed a new collaboration—testing whether it was truly changing attitudes and behaviors.

“Often diversity interventions are not evaluated,” Pietri says. “You could do a diversity training, and it could have worse effects or just no effect, and you’ve wasted all these resources.”

The filmmakers behind Picture a Scientist worked with 91��ý researcher Eva Pietra to study whether the film's approach to addressing bias in STEM was truly changing attitudes and behaviors. (Photo: Uprising Production)

So Pietri and her team designed a study to measure the documentary’s impact. They found that Picture a Scientist was prompting real-world action, not just raising awareness.

“One of the most consistent findings we saw was with information seeking. The more people felt transported, the more they engaged emotionally with the film, the more likely they were to want to learn more about gender bias,” she explains.

Likewise, the study showed that this information-seeking behavior often persists after the initial screening.

“One really positive finding is that people who watch the film are motivated to continue looking up these issues and figuring out how they can make their workplace more equitable. They’re putting themselves in a position to keep gaining knowledge,” Pietri says.

Indeed, participants surveyed a month or more after watching the film reported stronger effects than those who answered immediately, suggesting that the film’s impact is long-lasting.

Pietri believes its entertainment value is partly responsible.

“I mean, this documentary is created by filmmakers, right? They’re not just academics. They know how to create something that’s really entertaining,” she says. “That’s why it was streaming on Netflix, because people, even outside their institutions, are just excited to watch it.”

Of course, stories don’t just educate. They also inspire.

Traditional bias training often focuses on the barriers marginalized groups face, which, while important, can leave viewers feeling hopeless rather than empowered. But when Picture a Scientist viewers see women overcoming challenges, it creates something valuable: role models.

“The film doesn’t just show bias,” Pietri says; “it also highlights these incredible women in STEM. And for students, especially female students of color, that representation is powerful.”

Limiting objections and creating change

Research shows that when people feel forced into a training session, they often react defensively, resisting the very ideas the program promotes. But storytelling doesn’t elicit the same pushback. Instead of feeling lectured, viewers become immersed in a story where they can process difficult topics with less resistance.

"One really positive finding is that people who watch the film are motivated to continue looking up these issues and figuring out how they can make their workplace more equitable. They’re putting themselves in a position to keep gaining knowledge"

That’s one reason Pietri believes storytelling and creative interventions will play an important role in the future of diversity training in STEM.

“This story-based approach addresses some of the limitations of traditional diversity workshops. Aside from people maybe being actually excited to see it and participate, it’s also very scalable,” Pietri says.

“We can show it without having to train facilitators or fly people out to host a panel or host multiple live sessions over Zoom. It’s really easy to scale and it’s not super expensive,” she adds.

Training alone won’t eliminate STEM’s gender-bias problem. However, Pietri’s work suggests that the right intervention can make a difference.

“I think one danger with anything that talks about bias is that it might dishearten people,” she says. “But storytelling, when done right, can motivate people to do something about it.”

Perhaps the most important lesson is that when building a more inclusive STEM community, in a field that thrives on innovation, a good story can be just as efficacious as the right experiment.

“If we can use the small windows for change opened by stories like this to make progress in reducing inequality and suffering, that would be a real win for current and future generations,” Pietri says.

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91��ý researcher Eva Pietri studies how stories can help address gender bias and create inclusivity.

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