Three faculty members of the UVA School of Engineering and Applied Sciences, James (Jimmy) Burns, Coleen Carrigan, and Liheng Cai, join the show to discuss their research and the path that led them to become honorees of the Presidential Early Career Awards for Scientists and Engineers. The PECASE Award is the highest honor bestowed by the U.S. government on outstanding scientists and engineers beginning their independent careers. From studying the culture within engineering, redefining our understanding of biomaterials, to assessing the integrity of space stations, it all has a home at the School of Engineering and Applied Sciences.
- Transcript
Transcript 0:08welcome to Who's in STEM i'm Ken Ono your host and the STEM adviser to the provost and the Marvin Rosen Blum 0:14professor of mathematics at UVA our goal is to evoke flights of imagination and wonder by showcasing the 0:21cornucopia of all that is STEM at UVA the marvelous world of UVA science 0:26technology engineering and mathematics now today's episode is really really 0:32special and uh we we will celebrate the achievements of three star junior 0:39faculty faculty that the university is very proud um are on grounds and sort of 0:45to set the stage for what I mean by that um let me take you back in time to 1993 0:52in 1993 I defended my PhD thesis at UCLA and I felt an overwhelming lack of 1:00confidence and that is an understatement my hope was that at least four people in the world would care 1:07about my work in number theory coincidentally there were indeed four individuals on my committee and they 1:14held my future in their hands and I'm profoundly grateful that they passed me 1:20however even after defending my thesis I couldn't shake the belief that I didn't have what it takes to be a successful 1:27scientist there was no evidence to suggest otherwise that year I applied for nearly 200 university positions and 1:34the harsh reality is that I didn't get a single interview this experience of rejection 1:40only reinforced my belief that I was an impostor somehow I pieced together a 1:47series of one-year post-doal appointments which just kept my dreams of an academic career alive alive just 1:55long enough to leave open the chance that I might be able to produce work 2:00that mattered to someone for me I was very lucky and it actually did come in a 2:05flash of insight and I'm so grateful that because of those opportunities I 2:11was able to solve a 100-year-old conjecture in mathematics that actually even made world news if you can believe 2:16that and a few months later I was stunned to receive an invitation from the White House because I had been 2:23selected as one of 60 scientists nationwide to receive an award called 2:28the PCASE the Presidential Early Career Award for Scientists and Engineers this 2:34honor represents the highest recognition that's awarded to beginning researchers in STEM fields by the federal government 2:42i received my prize from Bill Clinton at the White House and well as cool as it was to go to the White House what was 2:49really important was the recognition from peers who saw value in my work and 2:55who had recommended me for this prize it was as if I transitioned from impostor 3:01to expert overnight now I believe that the three guests that we have today probably experienced 3:08something similar today we proudly celebrate the achievements of three faculty members who have just been 3:15awarded PKAS awards in 2025 james Jimmy Burns Colleen Carrian and Leeh Kai as a 3:23new member of the department of electrical and computer engineering myself as an affiliate professor I couldn't be more thrilled with these 3:30three scientists because they're being recognized for their works that speak to 3:37engineers so Jimmy Colleen Lee Hang welcome to Who's in STEM great to be 3:42here thank you Ken thank you Ken where to start what was going through your 3:47mind when you found out that you were receiving a prize from the president 3:53yeah you know I just I was really excited you know I think uh I wasn't expecting that uh and so I almost just 4:00deleted the email because it was from uh the NASA director and it seemed kind of fishy but as I read into it and clicked 4:07on the link which was probably a bad idea i saw that it was something official and you know honestly it was going through my mind is I was just very 4:14very thankful to the mentors that I had and opportunities that I've gotten um through my time in the US Air Force and 4:20here at UVA and I just been very blessed by that and so I I think probably the biggest thing going through my mind was 4:25being thankful well Colleen what was going through your mind i was in absolute shock like Jimmy I at first 4:32didn't believe it and then when it started to sink in I just was shaking and then the next thought was how can I 4:38share this with the people that made this possible lee Hang your thoughts yeah so um I I 4:45knew this is going to happen i think that was many months ago that was the last year when uh the the officials 4:52reached out to me asking for information for the background check so then I emailed my program officer from SF they 4:59told me that they just nominated me like two years ago so it's a really a long process so I know it's coming but it's 5:06good to know it's going to be finalized yeah you always wonder you know it's not like the checks in the mail and 5:12certainly the email isn't like the email you get from the Nigerian prince promising great prizes this is a big 5:17deal this is a big deal now there are three of you and you do very different 5:22things in your research and and and I'd like to talk about that i certainly want to begin with that so Colleen tell us 5:29about your research what are you being recognized for with the PKS well I um am a feminist anthropologist 5:37and I study um women and non-bionary practitioners who navigate uh male-dominated fields and I um am lucky 5:45enough to have been able to have the skills to do this because um really early on in my undergraduate career I um 5:53had an internship a full-time internship at the Women's Bureau at the Department of Labor and I got to not only read 5:59quantitative research on labor stratifications in our on economy and our US workforce but I also got to hear 6:06stories from thousands of women workers who were navigating non-traditional fields and their stories really moved me 6:13and it it it it made me realize that that's what I wanted to do for a living which is um amplify those stories and 6:20study it as theory so I can make change in the US labor economy and so now I'm I 6:25I put myself through grad school um as an anthropologist but I worked as a research associate at a national science 6:32foundation advance center which is to advance uh women faculty in STEM and so 6:38very early on in my graduate career I got to be a part of this social movement to broaden participation in science and 6:44engineering particularly in engineering and I got to got to be part of monthly mentorship lunches is I got to be part 6:50of quarterly um leadership uh development professional development events and so very early on I got this 6:56mentorship from a lot of women in science and engineering that has helped me in my own career and so I'm trying to give back to those pioneers who um have 7:04persisted in science and engineering uh despite significant barriers of um 7:10because of race and gender and sexuality and socioeconomic status and so being having the tools from anthropology where 7:16you can collect people's stories and gather them together to create theory and then that theory can be put back into the world to help other people 7:23navigate those problems and find solutions to them i'm just feeling so grateful for for the past you know 20 7:29years having been part of this movement um from other feminist leaders to be able to give back to society and and 7:35help make our labor force safe and equitable to all workers so with the PKS 7:41award the work will go on and do you have a a project or a program that we 7:47can look forward to over the next couple of years absolutely in my lab valuing the social and computing um which is 7:53mostly an undergraduate lab and um I'm right I just finished I published a book 7:58cracking the bro code last year which um codifies the theory that I just mentioned and the PC case hopefully will 8:05um bring recognition to the people that make my research possible which is which 8:11are the um the the women non-binary practitioners and male allies who 8:16support diversity equity and inclusion in science and engineer ing and I'm hoping then to also write a second book 8:23and my second book the working title right now is dethroning bro code bosses so my contribution of of theorizing on 8:29the bro code and how it operates not only in um cultures of high-tech but how those um cultures of high-tech are then 8:36exported to broader society um I'm hoping that my theories especially in my 8:41second book too will um will help make change in US society thank you Colleen so did everyone catch that the book is 8:48called Cracking the Bro Code um you know it reminds me of a recent 8:54episode that we had with Mar Hicks and Marggo Lee Sheddderley so this kind of work parallels uh their work and so for 9:03listeners who remember that or maybe for those who don't remember that go back and listen to that episode because we 9:09were talking then about the problem of the hidden figures there was a famous movie called Hidden Figures based on 9:15Margot Lee's book um largely centering on four or five African-American women 9:21who uh were the human computers in NASA but for the four of them that became 9:27famous there are thousands whose stories remain untold and this is the very valuable work of Mar Hicks and Margot 9:34moving forward so it's it's it's it's wonderful Colleen that in the spirit of these you know these initiatives that 9:41you're here leading the way lee Hang congratulations tell us about your work 9:48what are you known for oh yeah sure so um I work in the area of soft 9:53biioaterials and some examples has ice cream and a steak those are examples right um in particular we work on a 10:01material called elastm or rubber so since Charles Kulier invented the 10:07rubber that about like 200 years ago we know that when you make a softer rubber 10:13they become more stretchable or the other wise is that so if you make a 10:18stiffer rubber they become less stretchable now people know that stiffer materials are less stretchable so uh we 10:26we were trying to solve this challenge over the past many years and about five years ago we we we thought we have an 10:32idea on how to solve this one then we wrote a proposal then this proposal was 10:37supported by the answer of career award so after five years of work we saw okay this idea is is is true right we can we 10:45can show this idea really works that's really what really allows to really be gain this organization yeah so the idea 10:51is a new process in in manufacturing yeah the idea is that so is is a new uh 10:58fundamental design principle is not a really engineering it's about a really a scientific innovation is uh trying to 11:04find a new ways to use a different building blocks to make networks to make a rubber so we we we founded that if you 11:12try to uh try to engineer try to engineer two things one is what are 11:19called a molecular weight mhm which determines how stiff the materials it is 11:24the second one is that is the length scales they can store right so basically 11:29we designed a very special molecule which can have the molecular weight and 11:35the the length they store independently controlled then we can use them to 11:40together to have them sort of assembled to a network make a rubber which can be stretched by nearly 30 times which is 11:47really amazing yeah so help us picture perhaps by giving examples where where 11:53would this material be put to use in our daily lives moving forward where can we expect to see professor Kai's material 11:59in our at home yeah so now uh you can use this really for many cases because 12:05the uh elastimas or like a rubber that are sort of like so prevalent in the modern society that the major components 12:12of the automobile such as tires right that also being used as the major components of this like home appliances 12:19so basically anything you want to interface you want to have something that soft and compliant but also 12:25stretchable so now we are trying to use this material to make stretchable electronics software robots and also 12:31we're trying to make them uh use 3D printing to make the different architectures in addition we use them as 12:37medical devices so everywhere yeah basically this will really change the way how people make rubber fundamentally 12:44thank you for sharing that jimmy your work give us uh an overview of your work 12:50as a NASA NSF funded scientist happy to do so and so I you know I sit in the 12:55material science uh and engineering department which is sometimes kind of a forgotten figure in the engineering 13:01school you know you folks know what mechanical engineering electrical engineering is but the material science department is cool because it kind of 13:07touches on touches on everything and so the work that I do uh within the material science department is focusing 13:14on the role of environment on the structural integrity of metallic 13:20components right what's neat about that is that has a role of materials a role of mechanics and a role of chemistry and 13:27so you know you can say man that's complex but that's also reality which then makes it kind of a fun projects to 13:34be able to work on right and what we try to do is ensure structural integrity so if you're flying on the plane you hope 13:39some smart people smarter than me are out there making sure the plane wing doesn't fall off right you want it to 13:44have structural integrity and that's true in a whole bunch of different applications whether it be the 13:49automotive world um the marine world the aerospace world biomedical if you have a 13:55hip replacement that's a a metal titanium typically inside an environment under load so how does the material 14:01respond when does it break and that sort of thing it's in the oil and gas the nuclear community uh you know it's kind 14:08of neat one of the big things now is the uh hydrogen fuel economy you want to have a hydrogen fuel economy you're 14:13going to have to transport that hydrogen that embredles materials causes degradation of structural integrity so 14:19you know one of the things I pro uh probably what I got the award for was from NASA and it's actually relevant to 14:25the space station as well and so there there's a project that we've been working on um unfortunately there was a 14:31a material system used on a part of the space station um that was prone to 14:36environmental cracking and I've been uh very blessed to be able to be a subject 14:41matter expert um to help provide guidance on uh it's actually really a neat thing of how academia can provide 14:48relevance for about 15 years actually for a Navy program and we worked on this aluminum magnesium alloy systems um and 14:55environmental cracking on those to understand the mechanisms what's caused it uh all the way down to the atomistics 15:01of causing decohesion of two interfaces right um and now we have been able to 15:07harness all that good work that was done at UVA to be able to provide engineering support to the to the NASA engineers as 15:14they try to navigate this challenging problem so uh I think of Skyab which 15:19crashed to into the ocean after a few years of orbiting uh Earth but then I 15:24think you're speaking of things like the International Space Station let's talk a little bit about the environment in 15:30which that device has to survive it's very different from uh what we expect of our materials here on Earth so what are 15:36the challenges that you face that makes your work on these alloys so critical you know the answer might not be quite 15:42as sexy as you think right and so the I want to go out in outer space right so that's a whole lot of nothing and vacuum 15:48so So that sounds pretty sexy to me yeah and you know but it's a little bit more innocuous than that you know it's it's 15:54actually a problem that is likely arising from the fact that it on the interior of the space station you need 16:00to have astronauts there right and they need to be able to live in a in air in a humidity controlled environment and that 16:06kind of stuff and and as they are there you have perspiration you have sweat you have things dissolve that can deposit as 16:13that deposits you can have deloquestence which if you ever go out to your car in the morning time or something like that 16:18you know it hasn't rained but maybe there's a thin film of electrolyte there right now all of a sudden you're in 16:24space on outside it's really cold it's really dry but on the inside maybe you have a a small electrolyte that can then 16:30interact with the material under a given load so again you know mechanics materials environment and then that 16:37causes these issues and so it's been very fun to work with experts on uh 16:43environmental control experts on all of these different things uh within the NASA community and then be able to 16:48provide a small part uh uh of knowledge base that we have from a material science perspective to provide insights 16:55into the uh cracking behavior i see so I obviously had it completely wrong i was 17:01imagining that it would be the radiation from the sun that would be uh destroying 17:06the integrity of the skin the shell of the space station but yeah I I I imagine 17:12that what you described is clearly a much more difficult problem not quite as sexy as that but I guess it uh you know 17:17sometimes the the real problem solving the real problems or just uh dealing with issues that we've known about for a 17:22long time but just in a different context um and so what's kind of fun about that you know that that's one 17:28aspect of what we do but we work with the Navy on environmental cracking on boats and a big program on airframes and 17:35um look at uh stress corrosion cracking and nuclear storage casks and what 17:40what's fun and I've kind of given my uh pitch to uh people anybody that would want to work with us is you know we do 17:48stuff that then integrates into so many different different disciplines and that's kind of cool about material 17:53science overall but also Alo kind of an interesting thing about the environmental cracking uh specific 17:58discipline great well thank you Jamie so as you've heard from our three uh 18:04scientists that the work spans here at UVA it's incredible in its in its range 18:11from an anthropologist studying culture in in STEM fields and engineering to a 18:18biomeaterials expert to an engineer studying the integrity of space station nations uh that's what we have here at 18:24UVA and it's and it is really amazing so thank you for sharing so I have the feeling that um your personal stories 18:31are probably just as diverse as as your research um and I I kind of want to 18:36touch on that whether you recognize it or not with this great honor you now 18:42will serve as role models for your students and and other faculty and and and well the university of course and so 18:50I think it's would be a good opportunity for us to talk about your personal stories your career journeys what 18:57sparked your passion how did you navigate your way to your current 19:03position here as a worldleading scholar maybe we'll lead off with you Lee Hang 19:09oh yeah sure so um Um I changed my fields almost three times during my 19:15career so when I was undergraduate in college I studied um uh physicus 19:21theoretical physics basically I just calculations mathematical equations and that's what I do but then I realized you 19:28didn't like it my heart but okay oh yeah I I did really well though and I like it 19:34very much but then I I also learn biology a little bit i thought really the future is biology right so but then 19:41that was really dilemma because biology deal with molecules and cells or as 19:47physics deal with atoms and quantum like electrons which are of different length 19:53scales that are so different so then can I do something between then I was 19:59thinking about something that I can bridge the length scales uh from this 20:05kind of atoms or molecules to the cells then I choose polymers polymers is just 20:10a a like a proteins is kind of like a long stringy molecules which connects by 20:16molecules so then I decided to go to polymers for my growth study uh this is 20:22the one time I change field right changing my field uh during this time I did two things one is still doing the 20:28theory doing the calculations on how to predict the behavior and and the properties of a polymers on the other 20:34hand I managed to work with a doctor from medical school uh to work on the 20:40human lung defense basically the question was that as we are talking right we have to breathe and this 20:46process brings in numerous infectious particulates in the lung how do the lung I try not to think about that but okay 20:52yeah yeah but how the lung fall against them right so as as long as this is really a long signing question so I was 20:59able to use the concept and the knowledge from the polymers soft matter to uh made a discovery and the discovery 21:06was really publishing science as cover article that's from my PhD work so I was also where did you do that uh that was 21:12like uh UNCC Chapel Hill Chapel Hill i was really lucky to work with a polymer 21:18physicist Michael Rubenstein and he's one of the world's best polymer physicist uh theoreticians and he wrote 21:26a textbook on polymer physicus which is basically used worldwide um but then 21:31when you discover something by experiments is so important and so interesting then you realize okay you 21:37need to do something else right then uh I I say experiments are more interesting 21:43are more fascinating then I decided to switch again so during my postto training I just switched from theory to 21:50experiments only so I did a very long post talk about like a four and a half year Harvard right uh with with a 21:57professor specialized in a soft matter and also but many experiments and after that then I realized that okay so I can 22:04become independent to my own lab now my lab like focus on experiments but I use 22:09a theory as a hobby yeah but would you classify yourself as an experimental engineer or more of a producer producer 22:16of materials so uh I wouldn't call them like engineer I would call them a scientist right so we we we're trying to 22:22really solve fundamental challenges in the meantime we use engineering processes to make them useful Oh I see 22:29mhm great well Colleen your passion how did you your path your story well I grew 22:36up in my parents bookstore Notes and Quotes so I've been working at a bookstore since I was a little kid being surrounded by books from a young age and 22:43having access to unlimited books from my um my folks um really inspired me to 22:48want to become a writer i remember being a little kid pointing at the bookshelf saying "I want to be a doctor of books." Even before I really knew what that 22:54meant um and then I went on to study at um College of Holy Cross i studied English and I was very um active in the 23:01feminist movement there trying to make sure that women have the um the same opportunities respect and regard um at 23:08in in higher education i did a full-time internship as I mentioned at the Women's Bureau of the Department of Labor and 23:13that's where what really got me interested in studying cultures in um non-traditional fields and so um after I 23:20did my capstone based on that internship experience uh which won um an award I um 23:26went to work for big tech um moved to Seattle and worked at a very famous big tech corporation and that's when I 23:33realized that all the theory that I had written and studied about and written my capstone on sexual harassment in 23:39male-dominated fields wage gap um I was experiencing it personally so I realized 23:46with theory became my own lived experience so when I went wanted to go back to grad school I used that as a way 23:52to to become an anthropologist where you can turn stories into theory and then apply that theory back onto the world to 23:58make meaning and understanding of it so you can make change - Links