Math in Paris

Math in Paris

The need to take a summer math class evolved into an amazing summer in Paris for Avery Hazelbaker, a mathematics and pre-med major. “I needed to take a math class, so I just searched "learning abroad differential equations" on Google and the CEA Paris Engineering Program popped up.”

Hazelbaker had a “bucket list” of things she wanted to do before she graduated from the U, and studying abroad was one of them. “I had traveled to Europe with my family when I was younger,” she said, “but I’m not sure I appreciated it enough at the time. I wanted to go again, study math, and really dive into the culture.”

She gives high marks to the CEA program because of the math instruction and the opportunity to meet different kinds of people. “I absolutely loved my math professor—he was so much fun, very nice, and extremely knowledgeable,” said Hazelbaker. “He would spend 10-15 minutes of class going over some common French words and phrases to help us understand and become more comfortable with French culture.”

She liked the differences between the U.S. teaching and the French learning style. “In France, the teachers expect the students to write out what they’re doing for each step, so they can confirm that students know what they’re doing,” said Hazelbaker. “At the U, instructors assume students know why they're doing something if the work is correct.”

During her stay, she traveled on weekends to various cities in Europe. She also spent time getting to know the “arrondissements” in Paris. She was able to see a World Cup game, visit several chateaus in the Loire Valley, and attend quieter events, such as a classical music concert at L'église de la Madeleine.

Hazelbaker was fortunate to live in housing that included not only CEA students but also other students who were attending universities in Paris. “I became extremely close with three girls,” she said. “One was born in South Africa but has lived most of her life in France, another was from Germany, and a third had family in Africa but had been born in Lyon. These girls showed me what it was really like to live in Paris and how to make the most of the experience by immersing myself in the culture and not just seeing it from the outside. I didn’t know that I would be living with people who weren’t Americans, but it was the best thing that could have happened. I made the best friends and had experiences that wouldn’t have happened if I hadn’t been living with people from another culture.”

She encourages her U classmates to consider learning abroad. “Everyone should try it if they have the chance,” said Hazelbaker. “It’s such an amazing experience. I know it sounds like a cliché, but you really do learn a lot about yourself, and you become a better person. I would love to return to Paris.”

Going with the Flow

Going with the Flow

John Sperry

Retiring botanist studied how plant's xylem tissue carries phenomenal amounts of water to tree leaves where it evaporates and influences regional weather patterns.

John Sperry grew up in Normal, Illinois, but his interest in plants–eventually their vascular function–would propel him into work that was far from standard in botany via Duke University and, eventually Harvard where he earned his PhD. At Harvard his Swiss-born mentor Martin Zimmermann was considered among the top plant physiologists in the world and a scholar whom Sperry credits with, more than anyone else, “showing him how” to do research. Even so Zimmermann strongly questioned the ability of Sperry’s proposed, novel technique to measure the blockage of vascular flow by cavitation.

It was the ultimate success of that technique and new discoveries of how vascular tissues, or xylem in particular, function in conducting water and dissolved nutrients upward from roots, that would become the subject of Sperry’s PhD thesis. And it was that thesis and the questions it  spawned that laid the foundation of all of the research he would do for the next 30+ years, including a stint as a post-doc at the University of Vermont prior to his arrival at the University of Utah in 1989.

“As humans, we are acutely aware of the importance of maintaining vascular function,” Sperry’s Research Statement reads. “To plants it is no less critical. My laboratory investigates hydro-vascular structure and function in plants in relation to their ecology, physiology, and evolution.” The scale of this function in plants is, he explains, a “phenomenal process. The sheer quantity of water moved through plants often exceeds river flow on a watershed scale,” he explains. “The plant's xylem tissue carries all of this water to the leaves where it evaporates and influences regional weather patterns.”

It takes “watershed scale” flow for plants to obtain CO2 from the atmosphere through their open stomata. It’s counter-intuitive, but the transport is driven by negative liquid water pressure, “a remarkable fact,” says Sperry “that will always irritate physicists” who often aren't as familiar with  metastable fluids as  is a plant physiologist.

Sperry and his lab study how plant form and function have evolved. To do this they have developed more efficient technologies for the larger data sets required. Sperry custom designed centrifuge rotors to  quickly expose the vascular system of plants to a known negative pressure. This in turn has allowed him to create the kinds of vulnerability curves which improve prediction of plant water use and to help move his research toward macro applications in forests to predict plant responses to climate change.

What does the coordination look like between regulation of photosynthesis and environmental conditions? The answer lies in predicting what the stomata will do.  Stomata are typically found in the epidermis of plant leaves. Specialized “guard cells” surround stomata and function to open and close stomatal pores,  balancing the trade-off of water evaporation for required carbon dioxide.

“We … concentrate on the fundamental carbon-for-water trade-off that confronts all terrestrial plants,” continues Sperry. “Photosynthesis requires the plant surface to be porous to CO2 diffusion, but at the cost of also being porous to evaporative water loss.” Indeed, the xylem has been called "the vulnerable pipeline,” part of an elaborate system that includes “a transport system that teeters on the edge of physical possibility.” Failed water transport, or “cavitation,” is caused by water stress or freezing. Over the years, Sperry has learned that some plants are more vulnerable to this kind of “spectacular failure” than others. “This turns out to be part of the answer to the question of why some plants grow where they do when others cannot,” says Sperry. Vulnerability to cavitation provides the key to predicting how stomata respond to environmental cues, a missing element that Sperry and colleagues have integrated into predictive models for how plants respond to their environment.

Sperry with his centrifuge.

It’s not surprising then that Sperry’s work in plant hydraulics–the water stresses and trade-offs they face–has had a profound impact on predicting how rapid environmental change will affect the future of plants and forests. This according to U ecologist and Sperry colleague William “Bill” Anderegg. Before his own appointment in Biology, Anderegg, who was studying Colorado forests, spent time in Sperry’s lab. There he learned first-hand what was confirmed later for him about Sperry’s mentoring of young researchers.

“I attended a major conference in the field recently,” says Anderegg, “where there was a ‘mentor tree’–an artistic set of wooden branches where young scientists anonymously wrote the name of someone who had changed their career…. John's name was all over the tree and was the most frequent name by far.”

Sperry will retire from the University of Utah in December, so it’s a time to look back on a career that started, in retrospect, as early as kindergarten in his hometown of Normal. “Of course I was also obsessed with being a truck driver,” he adds. “But I did draw lots of trees and enjoyed watching our teacher demonstrate the ascent of food coloring in the transpiration stream of a celery stalk.”

But like a true scientist he is always looking forward as well, not just finding a home for that centrifuge with the custom-made rotors, but enlisting the programming skills of undergraduate lab associate Henry Todd. Todd, together with lab mates Martin Venturas and Yujie Wang, is  facilitating  climate change simulations of 520 combinations of 8 species in 20 sites across the country based on  six climate projections and two emissions scenarios … over 30 years.

John Sperry will not be parsing through this kind of macro data for much longer, limiting himself to just a few more papers and farewell meetings. Retirement will  allow him  more time to adventure with his wife Holly in their truck camper and to be in his  favorite laboratory: the outdoors. He and his canoeing buddies also look forward to expanding their summer-long explorations of northern wilderness, a place where you can travel over 600 miles under your own steam and not see another soul for a month and a half. Sperry is harking to the dictum: "no one on their death bed wishes that they had spent more time at work."

- by David Pace. First Published in OurDNA Magazine, Fall 2019

Volunteer Form

Volunteer Form


Thank you for agreeing to volunteer your time for Science Day at the U. Science Day is the largest student recruitment event on campus! The event introduces high school students to the laboratory research and career opportunities in science, engineering, and mathematics.

The University of Utah approved a policy addressing the Safety of Minors participating in University Programs. In an effort to provide for the safety of our minor participants you will notice a few additions to the registration process this year.

  1. You will need to provide your legal name, as listed on your driver’s license or official state ID. University staff will need to check your ID the day of the event.
  2. The registration form request’s your date of birth and mailing address. College of Science staff will check all volunteers on the National Sex Offender Registry database.
  3. Volunteers and presenters must also complete a training session on the code of conduct and reporting obligations.

We realize these extra steps may add time to our process, and we appreciate your patience. The safety of our minor participants is very important to the University of Utah and the College of Science.

For questions contact Lisa Batchelder at 801-581-3374 or

Science Day - Volunteer Application
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**Bring your license to the volunteer meeting on October 22nd.**

Staff: Jose Rojas

Facilities manager at the School of Biological Sciences for 20 years, Jose Rojas, probably knows more about the ins-and-outs of how labs operate than most principal investigators. Like the biology subjects U biologists examine—from cone snails to mitochondria, and from mammals to tiny round worms of C. elegans—Rojas’s work in retrofitting lab spaces requires prodding, perturbing and replicating.

Labs in the four biology buildings (Aline Skaggs [ASB], South Biology, Talmage Building and Life Sciences) are constantly in a state of flux: living organisms in their own right. With more tenure-line faculty/principal investigators than most academic units, Biology relies on Rojas and his team to be in a constant state of demolitions, bidding, implementing hazard waste abatements, and pricing and securing equipment like million-dollar microscopes, tanks, and cages, wind tunnels and centrifuges. Then there’s also that OTHER lab: BioKids, and NAEYC accredited, year-round Early Childhood Program located at the School in Building 44.

Rojas’ work also requires an artistic side, designing exhibits like the museum-grade cabinet that now houses the gene-targeting equipment Dr. Mario Capecchi used to do his foundational research in the School of Biological Sciences which led to the good scientist’s Nobel Prize. Currently Rojas is designing a display, “Biology Under Cover,” of selected journal covers over the decades by School faculty now memorialized in metal in the lobby of the Aline Wilmot Skaggs Building.

Rojas’ work also requires an artistic side, designing exhibits like the museum-grade cabinet that now houses the gene-targeting equipment Dr. Mario Capecchi used to do his foundational research in the School of Biological Sciences which led to the good scientist’s Nobel Prize. One of his last project was designing a display, “Biology Under Cover,” of selected journal covers over the decades by School faculty now memorialized in metal in the lobby of the Aline Wilmot Skaggs Building.

Rojas’ work has not gone unnoticed: in 2017 he received the prestigious District and University Staff Excellence Award in 2017. A native of Puerto Rico, he has made his home in Utah since 1983, but still returns to Florida and points beyond at least annually, bearing his signature bounty of local macaroons for the staff back at the U. He and his staff regularly host a BBQ on the roof of the South Biology building next to the expansive greenhouse.

Rojas could pretty much tell you everything that’s going on in there as well.

These are big, steel-toed boots to fill. At first blush you might wonder how an artist ended up as the new facilities manager here at the School of Biological Sciences. The job requires not only a thing for materials and construction, but a good dose of management and intuiting the quirky needs of faculty/principal investigators whose labs house everything from wind tunnels to million dollar microscopes; from mice to fruit flies; and plants to mammals. Never mind the anatomy lab: one of only two labs of its kind on campus, housing full cadavers.