Nate Linden: Rock climber, engineer, Sloan Scholar

Nate Linden has been curious about how things work for as long as he can remember. From a young kid pretending to be a plumber, to a high school intern developing an app to monitor blood loss during surgery, he figured out that engineering and math could help explain a lot of the mechanics behind the way the world works. After earning a degree in bioengineering and a minor in applied math at the University of Washington, Linden is now a PhD student at UC San Diego, where he found it was possible to pursue both his love of biology, as well as computational science. 

“My curiosity to understand how things work has always driven my passion for learning and made a career in research an obvious decision. I decided to pursue a Ph.D. because it enables me to pursue this career and to solve problems that impact our understanding of biology and medicine,” said Linden. “I chose UC San Diego because of the unique opportunity to work with both Professor Boris Kramer and Professor Padmini Rangamani. Entering my undergrad in bioengineering, I was passionate about tackling problems in biology and medicine. However, I quickly developed a passion for math and computation as I took more mathematics and computational science classes. When I was choosing where to do my PhD I was looking for opportunities to combine my interests in biology and computational science. At UC San Diego I get to study fascinating biology and medicine by developing and using sophisticated mathematical methods.”

Linden is working with Kramer and Rangamani, both in the Department of Mechanical and Aerospace Engineering, to build mathematical models of intracellular signaling systems, allowing us to study how cells respond to external stimuli. He is a Sloan Scholar, a fellowship awarded to 12 incoming UC San Diego graduate students each year. The fellowship is meant to stimulate fundamental research by early-career scientists of outstanding promise. Sloan Scholars receive a $40,000 award to be used over four years.

“A major challenge in constructing these models is ensuring that the responses we predict align with the responses we observe in experiments. To address this challenge, I develop and employ computational methods that calibrate our models to accurately predict the biology observed in the lab. We can then use these models to study how changes in cellular systems lead to complications such as cancer. My work ensures that we can 'trust’ the results that we obtain by simulating the biological system.”

Linden climbing in Red Rocks, outside of Las Vegas

Outside of research, Linden is an avid rock climber who ranked nationally in youth competitions. Though he doesn’t compete at that level anymore, he said that making time to climb not only helps him feel his best physically, but mentally too.

“I have been rock climbing since I was 10 years old, and I began competing a few years after that. Since high school, I have not competed on the national level, but I still try to enter local community events when I can. I do try to go climbing outside whenever I have spare time on the weekend. It definitely took some work to figure out how to manage my time between work and going climbing. The most important thing for me is realizing that I am more productive when I take time to get away from research. Climbing has been a hugely important part of my life, and making sure that I balance my time between work and climbing helps me be more focused at work.”

Unusual “cool flames” documented aboard International Space Station

A team of researchers, including engineers at UC San Diego, documented an entirely new class of fire aboard the International Space Station. The spherical cool diffusion flames, or simply "cool flames," could ignite development of the combustion engine of the future. Read the full release from the University of Maryland.

Cool flames are aptly named: They burn at extremely low temperatures and emit a near-invisible blue glow. (For comparison, a natural gas burner at high heat on a conventional stove top can burn at around 3100 degrees Fahrenheit/2000 Kelvin; a typical cool flame hovers around 900 degrees Fahrenheit/800 Kelvin.) They are also somewhat mysterious: As recently as 10 years ago, cool flames had only been theoretically predicted. First observed during an experiment aboard the International Space Station (ISS) in 2012, the cool flames appeared only briefly before the liquid fuel was depleted. The sighting catalyzed an emerging, rapidly growing field in combustion research.

Forman Williams, a professor emeritus of mechanical and aerospace engineering at UC San Diego, has been working on fire research and fire safety with NASA since the 1970s. For this most recent experiment and discovery, he collaborated with researchers from the University of Maryland and Washington University in St. Louis. The team launched to the ISS in late 2020 an experiment designed to generate controlled cool flames that burn, steadily, for at least two minutes. 

In a first for microgravity flame research, they achieved this feat—with the help of astronauts aboard the ISS testing a variety of gas fuels—on June 23, 2021. 

"This may help improve our knowledge of cool-flame chemistry, which is involved in the design of better internal combustion engines," said Williams. "I didn't expect to find these stable cool flames because the stabilization mechanism for them in droplet combustion is absent, but apparently there is a related stabilization mechanism for these gaseous fuels."

Williams has been involved in these experiments to better understand fire here on Earth by pushing the limits in space for decades, including leading experiments to improve fire-fighting techniques in space and better understand combustion on Earth, and leading the design of the experiments that led to the first observation of this new type of cool burning flames.

ISPE hosts Ideathon to bring student projects to life

By Melissa Hernandez

The International Society for Pharmaceutical Engineering student chapter at UC San Diego is dedicated to advancing pharmaceutical manufacturing professionals, and educating interested students about the field and career opportunities. The student organization provides opportunities for members to connect with industry professionals and further develop their skills, and the group found a way to do both simultaneously through their first Ideathon.

Participants at the first ISPE Ideathon

Anahid Foroughishafiei, a bioengineering student and ISPE project team chair, was inspired to develop the Ideathon event after her experience creating a student project team based on research she was conducting in the field of metastasis. Foroughishafiei thought that those types of opportunities should be shared with the broader student community at UC San Diego.

“I was working on a project where I wanted to make a computer model of what I was working on in the lab at Moores Cancer Center, and I thought it would be cool to work on something similar with other students,” Foroughishafiei said. “I didn’t want to be the only student who makes their own projects, so I thought ‘How do we make interdisciplinary projects with other undergraduate students?’ That is how the Ideathon first came to be.”

The International Society for Pharmaceutical Engineering recently held their first Ideathon where students, no matter their field of study, were encouraged to create projects within the pharmaceutical field while taking into account sustainability and socioeconomic factors. 

“We asked students to submit a proposal of a project they wanted to work on, and they could apply as a team or individuals that would be paired together based on preferences on the application,” Foroughishafiei said. “We had judges from different fields of engineering industry, and after the competition, three teams are now being supported and the upcoming board will help pair them with faculty.”

Foroughishafiei and the Ideathon team arranged for three industry judges from Nova Engineering, BD BioSciences and D&K Engineering, to determine the top three teams who will receive funding through the next school year for their projects.

One of the three winning projects was a 
telemedicine booth for patients from
low-resource settings.

Ultimately, the judges selected three winning project proposals: a telemedicine booth for patients from low-resource settings to virtually visit and have a private setting to receive medical care and guidance; a sensor that identifies pollutants in the air to help guide the user’s behavior outside based on air quality; and a wearable device to monitor the user’s health powered by using their body heat.

The organization is actively pairing each finalist team with a faculty member who will serve as a mentor, to begin working on their projects during the upcoming summer and school year. After a successful Ideathon--held virtually on Zoom-- Foroughishafiei hopes to continue this competition next year in person.

“Currently we are working on getting more funding for the team’s projects so that is the focus, but once we get the ball rolling and the projects started we can move forward,” Foroughishafiei said. “ISPE is really all about collaboration. I want the future to hold more opportunities like Ideathon, but to be very interactive and collaborative across campus.”

The Ideathon competition is a prime example of how ISPE provides opportunities for its members to be a part of a project and connect with industry professionals. Not only does the Ideathon do that, but it allows ISPE members to share these opportunities with students from across campus as well.

Sloan Scholar Kristen Susuki: keeping our structures safe through better analysis

Structural engineering PhD student Kristen Susuki is a fourth-generation Japanese American who came to San Diego by way of the Midwest: she hails from St. Louis, Missouri and earned her bachelor’s degree in mechanical engineering from the University of Wisconsin-Madison. At UC San Diego, Susuki is researching a type of numerical analysis called meshfree methods, which are used to more accurately understand and model the durability of structures during catastrophic failure.

“Normally when you need to analyze a structure, you are looking to find stress, displacement, etc,” said Susuki. “To do that, you try to break down the structure into simple geometry. You may not know how an airplane will deform when loaded because its geometry is complex, but you can approximate it by using a bunch of simpler shapes like cubes and tetrahedra.” 

While this method of using smaller shapes to break down a larger, more complex problem—which is called finite element analysis—works, it isn’t as effective when testing a large deformation.

“That's where meshfree methods come in. Meshfree methods are really good at analyzing these types of problems because they treat everything like individual particles, so they have applications to a lot of "extreme" events—landslide problems, fracture, explosive welding, etc,” said Susuki. 

Susuki studies these analytical methods in the lab of JSChen, a professor of structural engineering at UC San Diego. The story of how she came to work in this lab is a lesson in taking advantage of every opportunity thrown your way and not letting fear get in the way.

“Right before I started applying to PhD programs, I drafted up a list of groups and PIs that I was really interested in working with. As if by a stroke of luck, one of the professors that was high on my list came to my university for a guest lecture. There was an email floating around asking people in my department to host the guest professor for an hour during the day to fill out his schedule. I signed up, but then started getting so nervous because I realized that the email was meant for faculty members and current grad students. I almost took my name off the list because I felt so underqualified to even talk to this professor. Thank goodness I didn't though. That professor was Prof. JS Chen of the Structural Engineering department at UC San Diego, my current PI. In that hour that I was hosting, we chatted about research and food and life. We really hit it off, and from then on I was pretty certain that UC San Diego was my top pick.”

Not only is Susuki now a student in Chen’s lab, but she also received a Sloan Scholar fellowship, awarded to 12 incoming UC San Diego graduate students each year. The fellowship is meant to stimulate fundamental research by early-career scientists of outstanding promise. Sloan Scholars receive a $40,000 award to be used over four years.

Outside of research, Susuki loves to travel—she’s been to 43 states and 23 countries spanning four continents. While she doesn’t have a favorite location—“every place I’ve been has been so unique”— she’s most excited for a trip to Japan that was postponed due to the COVID-19 pandemic.

She’s also passionate about increasing female representation in her field of mechanics and in STEM in general.

“I remember in college, especially in my last two years, how few women were in my classes. The first time it happened, I was shocked. By the last time, I barely noticed because that had become the norm. Oftentimes, I was both the only woman and the only person of color in my classes, which felt overwhelming. Having mentors that looked like me really helped me overcome the self-doubt I was feeling because I was able to talk to them about their experiences as female engineers and relate to some of their struggles/frustrations. Representation played such an important role for me in my educational career, and I really want to pay it forward because it's hard to envision yourself doing something if you haven't seen anyone else like you do before.”