23 minute read
Open Resilience
RESEARCH OPEN RESILIENCE
In the “new normal” of 2020, many teams across all industries have moved to a remote work setting.
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But how do teams stay productive, communicate openly, and share information eff ectively? This is one of the critical questions that a group of researchers at UVM’s Complex Systems Center are investigating – how people, teams, and organizations thrive in a technology-rich environment and how information or miscommunications spreads in these environments. This research is informed by the work of a multidisciplinary group of researchers using tools and theory from infectious disease modeling, network theory, computer science, data ethics, management theory, and the science of stories. UVM faculty members Jim Bagrow, Laurent Hébert-Dufresne, Peter Dodds, and Chris Danforth, lead research in these (and many other) related focus areas and are working to establish CEMS as a hub for complex systems and data science, resiliency and open-source research.
A GENEROUS UNRESTRICTED GIFT OF $1M FROM GOOGLE OPEN SOURCE PROGRAMS OFFICE IN 2019 IS HELPING ESTABLISH CEMS’S COMPLEX SYSTEMS CENTER AS A LEADER IN THIS FIELD.
The gift comes from Google’s Open Source Programs Offi ce, a division of Google that manages Google’s use and release of open-source software and promotes open-source programming. UVM alumna Amanda Casari (M.S. Electrical Engineering and Certifi cate of Complex Systems, 2011) serves as an Engineering Manager on this team and leads Google’s research collaboration with UVM.
Amanda explains, “Our goals for this project focus on an accelerated timeframe – in just two years, I hope that we can uncover new methods for describing and observing open source communities and teams. There are low-level metrics that we use now to see productivity in teams and the growth of open source projects. Any improvement we can make on these metrics to identify what contributes to resilience in open source would be benefi cial.”
Teams Thriving Through Tech
So what is open source, and why is it so important to study it? Open source is, at its core, a type of software that enables users to study, change, and distribute this software. But open source is more than just the software - it’s a framework that defi nes how the software is created, released, shared, and distributed, as well as the community that is formed around it, often a small team that works remotely. An example is Python, an open-sourced programming language that is now used by an estimated 8.2 million people worldwide (surpassing the 7.6 million who use Java), yet it has very few full-time employees. What makes these teams thrive in a technology-rich environment? And on a larger scale – what makes a healthy team?
The goal of this project is to have a deeper understanding of the opensource ecosystem and distributed teams. Some of the questions they will be analyzing:
• What tools does a team need for success? • How does information (or misinformation) spread? • How do you establish a governing structure and clear team roles?
As the COVID-19 pandemic has pushed many teams and client meetings to remote operation, the value in this research becomes more apparent to all of us. Laurent Hébert-Dufresne, one of the Open-Source Complex Ecosystems and Networks’ (OCEAN) Principal Investigators, notes, “Open source communities give us a unique window into how groups solve complex problems and how ideas and culture emerge in decentralized communities. Better understanding that interplay will allow us to foster better communities and more creative solutions to important problems.”
This support from Google helps further a key goal of the OCEAN project, as noted by Principal Investigator James Bagrow, “Improving our understanding of team collaboration and communication enabling better and more effi cient software development, including open source development.”
A generous gift from MassMutual in 2018 to establish the Center of Excellence for Complex Systems and Data Science supports work at the Complex Systems Center with a focus on a better understanding of human wellness through data analytics.
INVENTING
THE WORLD'S STRONGEST SILVER
BY JOSHUA E. BROWN
UVM scientist Frederic Sansoz holds a sliver of the world’s strongest silver. The new form of metal is part of a discovery that could launch technological advances from lighter airplanes to better solar panels. Photo: Joshua E. Brown
Team creates metal that breaks decades-old theoretical limit, promising new class of super-strong and conducting materials
A team of scientists has made the strongest silver ever—42 percent stronger than the previous world record. But that’s not the important point.
“We’ve discovered a new mechanism at work at the nanoscale that allows us to make metals that are much stronger than anything ever made before—while not losing any electrical conductivity,” says Frederic Sansoz, a materials scientist and mechanical engineering professor at the University of Vermont who co-led the new discovery.
This fundamental breakthrough promises a new category of materials that can overcome a traditional trade-off in industrial and commercial materials between strength and ability to carry electrical current.
The team’s results were published on September 23 in the journal Nature Materials.
Inside a grain of silver, copper atom impurities (in green) have been segregated to a grain boundary (on the left) and into internal defects (long strings, streaming downward.)
Photo: courtesy of Frederic Sansoz
Rethinking the Defect
All metals have defects. Often these defects lead to undesirable qualities, like brittleness or softening. This has led scientists to create various alloys or heavy mixtures of material to make them stronger. But as they get stronger, they lose electrical conductivity.
“We asked ourselves, how can we make a material with defects but overcome the softening while retaining the electroconductivity,” said Morris Wang, a lead scientist at Lawrence Livermore National Laboratory and co-author of the new study.
By mixing a trace amount of copper into the silver, the team showed it can transform two types of inherent nanoscale defects into a powerful internal structure. “That’s because impurities are directly attracted to these defects,” explains Sansoz. In other words, the team used a copper impurity—a form of doping or “microalloy” as the scientists style it— to control the behavior of defects in silver. Like a kind of atomic-scale jiujitsu, the scientists fl ipped the defects to their advantage, using them to both strengthen the metal and maintain its electrical conductivity.
To make their discovery, the team— including experts from UVM, Lawrence Livermore National Lab, the Ames Laboratory, Los Alamos National Laboratory and UCLA— started with a foundational idea of materials engineering: as the size of a crystal—or grain—of material gets smaller, it gets stronger. Scientists call this the Hall-Petch relation. This general design principle has allowed scientists and engineers to build stronger alloys and advanced ceramics for over 70 years. It works very well.
Until it doesn’t. Eventually, when grains of metal reach an infi nitesimally tiny size—under tens of nanometers wide—the boundaries between the grains become unstable and begin to move. Therefore, another known approach to strengthening metals like silver uses nanoscale “coherent twin boundaries,” which are a special type of grain boundary. These structures of paired atoms—forming a symmetrical mirror-like crystalline interface—are exceedingly strong to deformation. Except that these twin boundaries, too, become soft when their interspacing falls under a critical size of a few nanometers, due to imperfections.
Unprecedented Properties
Very roughly speaking, nanocrystals are like patches of cloth and nanotwins are like strong but tiny threads in the cloth. Except they’re at the atomic scale. The new research combines both approaches to make what the scientists call a “nanocrystalline-nanotwinned metal,” that has “unprecedented mechanical and physical properties,” the team writes.
That’s because the copper atoms, slightly smaller than the atoms of silver, move into defects in both the grain boundaries and the twin boundaries. This allowed the team—using computer simulations of atoms as a starting point and then moving into real metals with advanced instruments at the National Laboratories—to create the new super-strong form of silver. The tiny copper impurities within the silver inhibit the defects from moving, but are such a small amount of metal— less than one percent of the total— that the rich electrical conductivity of silver is retained. “The copper atom impurities go along each interface and not in between,” Sansoz explains. “So they don’t disrupt the electrons that are propagating through.”
Not only does this metal overcome the softening previously observed as grains and twin boundaries get too small—the so-called “Hall-Petch breakdown”—it even exceeds the long-standing theoretical Hall-Petch limit. The team reports an “ideal maximum strength” can be found in metals with twin boundaries that are under seven nanometers apart, just a few atoms. And a heat-treated
version of the team’s copper-laced silver has a hardness measure above what had been thought to be the theoretical maximum.
“We’ve broken the world record, and the Hall-Petch limit too, not just once but several times in the course of this study, with very controlled Sansoz is confi dent that the team’s approach to making super-strong and still-conductive silver can be applied to many other metals. “This is a new class of materials and we’re just beginning to understand how they work,” he says. And he anticipates that the basic science revealed in the new study can lead to advances in technologies—from more effi cient solar cells to lighter airplanes to safer nuclear power plants. “When you can make material stronger, you can use less of it, and it lasts longer,” he says, “and being electrically conductive is crucial to many applications.”
TEAM BUILDS THE FIRST LIVING ROBOTS
Tiny 'xenobots' assembled from cells promise advances from drug delivery to toxic waste clean-up
The "xenobots" made worldwide headlines, with features on CNN, the BBC World Service, and in Scientifi c American, The Economist, Forbes, and more. Visit uvm.edu/cems for more! On the left, the anatomical blueprint for a computer-designed organism, discovered on a UVM supercomputer. On the right, the living organism, built entirely from frog skin (green) and heart muscle (red) cells. The background displays traces carved by a swarm of these new-tonature organisms as they move through a fi eld of particulate matter. (Credit: Sam Kriegman, UVM)
A book is made of wood. But it is not a tree. The dead cells have been repurposed to serve another need.
Now a team of scientists has repurposed living cells—scraped from frog embryos—and assembled them into entirely new life-forms. These millimeterwide "xenobots" can move toward a target, perhaps pick up a payload (like a medicine that needs to be carried to a specifi c place inside a
"These are novel living machines," says Joshua Bongard, a computer scientist and robotics expert at the University of Vermont who co-led the new research. "They're neither a traditional robot nor a known species of animal. It's a new class of artifact: a living, programmable organism."
The new creatures were designed on a supercomputer at UVM—and then assembled and tested by biologists at Tufts University. "We can imagine many useful applications of these living robots that other machines can't do," says co-leader Michael Levin who directs the Center for Regenerative and Developmental Biology at Tufts, "like searching out nasty compounds or radioactive contamination, gathering microplastic in the oceans, traveling in arteries to scrape out plaque."
The results of the new research were published January 13 in the Proceedings of the National Academy of Sciences.
Bespoke Living Systems
People have been manipulating organisms for human benefit since at least the dawn of agriculture, genetic editing is becoming widespread, and a few artificial organisms have been manually assembled in the past few years—copying the body forms of known animals.
But this research, for the first time ever, "designs completely biological machines from the ground up," the team writes in their new study.
With months of processing time on the Deep Green supercomputer cluster at UVM's Vermont Advanced Computing Core, the team—including lead author and doctoral student Sam Kriegman—used an evolutionary algorithm to create thousands of candidate designs for the new life-forms. Attempting to achieve a task assigned by the scientists—like locomotion in one direction—the computer would, over and over, reassemble a few hundred simulated cells into myriad forms and body shapes. As the programs ran—driven by basic rules about the biophysics of what single frog skin and cardiac cells can do—the more successful simulated organisms were kept and refined, while failed designs were tossed out. After a hundred independent runs of the algorithm, the most promising designs were selected for testing.
Then the team at Tufts, led by Levin and with key work by microsurgeon Douglas Blackiston—transferred the in silico designs into life. First they gathered stem cells, harvested from the embryos of African frogs, the species Xenopus laevis. (Hence the name "xenobots.") These were separated into single cells and left to incubate. Then, using tiny forceps and an even tinier electrode, the cells were cut and joined under a microscope into a close approximation of the designs specified by the computer.
Assembled into body forms never seen in nature, the cells began to work together. The skin cells formed a more passive architecture, while the once-random contractions of heart muscle cells were put to work creating ordered forward motion as guided by the computer's design, and aided by spontaneous self-organizing patterns—allowing the robots to move on their own.
These reconfigurable organisms were shown to be able move in a coherent fashion—and explore their watery environment for days or weeks, powered by embryonic energy stores. Turned over, however, they failed, like beetles flipped on their backs.
Later tests showed that groups of xenobots would move around in circles, pushing pellets into a central location— spontaneously and collectively. Others were built with a hole through the center to reduce drag. In simulated versions of these, the scientists were able to repurpose this hole as a pouch to successfully carry an object. "It's a step toward using computer-designed organisms for intelligent drug delivery," says Bongard, a professor in UVM's Department of Computer Science and Complex Systems Center.
A manufactured quadruped organism, 650-750 microns in diameter—a bit smaller than a pinhead. (Credit: Douglas Blackiston, Tufts University.)
Living Technologies
Many technologies are made of steel, concrete or plastic. That can make them strong or flexible. But they also can create ecological and human health problems, like the growing scourge of plastic pollution in the oceans and the toxicity of many synthetic materials and electronics. "The downside of living tissue is that it's weak and it degrades," say Bongard. "That's why we use steel. But organisms have 4.5 billion years of practice at regenerating themselves and going on for decades." And when they stop working— death—they usually fall apart harmlessly. "These xenobots are fully biodegradable," say Bongard, "when they're done with their job after seven days, they're just dead skin cells."
Your laptop is a powerful technology. But try cutting it in half. Doesn't work so well. In the new experiments, the scientists cut the xenobots and watched what happened.
"We sliced the robot almost in half and it stitches itself back up and keeps going," says Bongard. "And this is something you can't do with typical machines."
Cracking the Code
Both Levin and Bongard say the potential of what they've been learning about how cells communicate and connect extends deep into both computational science and our understanding of life. "The big question in biology is to understand the algorithms that determine form and function," says Levin. "The genome encodes proteins, but transformative applications await our discovery of how that hardware enables cells to cooperate toward making functional anatomies under very diff erent conditions."
To make an organism develop and function, there is a lot of information sharing and cooperation—organic computation—going on in and between cells all the time, not just within neurons. These emergent and geometric properties are shaped by bioelectric, biochemical, and biomechanical processes, "that run on DNA-specifi ed hardware," Levin says, "and these processes are reconfi gurable, enabling novel living forms."
The scientists see the work presented in their new PNAS study—"A scalable pipeline for designing reconfi gurable organisms,"—as one step in applying insights about this bioelectric code to both biology and computer science. "What actually determines the anatomy towards which cells cooperate?" Levin asks. "You look at the cells we've been building our xenobots with, and, genomically, they're frogs. It's 100% frog DNA—but these are not frogs. Then you ask, well, what else are these cells capable of building?"
"As we've shown, these frog cells can be coaxed to make interesting living forms that are completely diff erent from what their default anatomy would be," says Levin. He and the other scientists in the UVM and Tufts team— with support from DARPA's Lifelong Learning Machines program and the National Science Foundation—believe that building the xenobots is a small step toward cracking what he calls the "morphogenetic code," providing a deeper view of the overall way organisms are organized— and how they compute and store information based on their histories and environment.
Many people worry about the implications of rapid technological change and complex biological manipulations. "That fear is not unreasonable," Levin says. "When we start to mess around with complex systems that we don't understand, we're going to get unintended consequences." A lot of complex systems, like an ant colony, begin with a simple unit—an ant—from which it would be impossible to predict the shape of their colony or how they can build bridges over water with their interlinked bodies.
"If humanity is going to survive into the future, we need to better understand how complex properties, somehow, emerge from simple rules," says Levin. Much of science is focused on "controlling the low-level rules. We also need to understand the high-level rules," he says. "If you wanted an anthill with two chimneys instead of one, how do you modify the ants? We'd have no idea."
"I think it's an absolute necessity for society going forward to get a better handle on systems where the outcome is very complex," Levin says. "A fi rst step towards doing that is to explore: how do living systems decide what an overall behavior should be and how do we manipulate the pieces to get the behaviors we want?"
In other words, "this study is a direct contribution to getting a handle on what people are afraid of, which is unintended consequences," Levin says—whether in the rapid arrival of self-driving cars, changing gene drives to wipe out whole lineages of viruses, or the many other complex and autonomous systems that will increasingly shape the human experience.
"There's all of this innate creativity in life," says UVM's Josh Bongard. "We want to understand that more deeply—and how we can direct and push it toward new forms."
Haley Warren ’20 Receives Distinguished Honor
THE PHI BETA KAPPA HONOREE IS ON A FULFILLING ACADEMIC JOURNEY
BY SARAH TUFF DUNN
Phi Beta Kappa is considered the nation’s most prestigious honor society—only 10 percent of colleges shelter a chapter, and only 10 percent of students at
CASEY HUSBAND ’20 LAUNCHES GLOBAL DEFENSE AND MILITARY CONTRACTING COMPANY
BY SARAH TUFF DUNN
Can a backpack change lives—or, even better, save lives? It can, if it’s an EDGE Backpack designed and recently patented by Casey Husband, ’20, in response to the mass shootings that began fi lling the mainstream news more frequently when he was in high school.
“I wondered if there was anything that could be done to assist fi rst responders in their eff orts to minimize casualties and save lives in these scenarios,” recalls Husband, who proceeded to call as many police departments in the top 100 most populous U.S. cities to research what equipment might help in an active-shooter scenario.
The result was the transformative EDGE Backpack, which quickly detaches for fi rst-responder access to medical supplies during such emergencies. Husband tested “countless” iterations with police departments and eventually fi led for, and successfully earned, a patent to protect the unique and innovative design. “The tactical gear industry is fi lled with companies copying each other's designs,” says Husband, who persisted through several those colleges receive the key representing the Greek phrase “Love of wisdom is the guide of life.” At UVM, the membership (now totaling less than 4500 students since 1846) becomes even more rare for CEMS students, as the majority of invitations typically go to traditional liberal arts majors. This helps explain how Haley Warren ’20 reacted when she opened an email from the UVM Phi Beta Kappa chapter with some news. “At fi rst I thought it was a mistake—I wasn’t sure how I would have gotten in as an engineering major,” she says. “It doesn’t feel entirely real.” Warren’s studies focus on biomechanics and wearable robotics, inspired in part by her personal experience with Ehlers-Danlos syndrome, which weakens her joints and connective tissue. She’s been improving her own braces since she was 7 years old, learning how to dance fl uidly
The EDGE Backpack quickly detaches for fi rst-responder access to medical supplies during emergencies.
denials and three years of paperwork for the approval. He’s also founded a company called Lazarus, which is now focusing on commercial manufacturing and international sales to address global security threats.
“Innovation at UVM is growing in leaps and bounds,” says Dan Harvey, UVM’s Director of Operations to the Vice President for Research. “There’s a resounding yes echoing across campus to entrepreneurship and working toward not only answering the important basic science questions, but also applying that knowledge to applying solutions.”
“I wondered if there was anything that could be done to assist fi rst responders in their eff orts to minimize casualties and save lives in these scenarios,” Husband says
about how he decided to direct his research and eff orts. with the right devices, and has brought her research skills not only to UVM but also to Rutgers and MIT. Love of wisdom—and not just knowledge—has guided her academic journey.
“It’s not just about learning, but also learning through experience,” says Warren, who plans to pursue a Ph.D. in mechanical engineering after graduation. “And it’s not just about questions, but understanding which questions to ask.”
RECENT HONORED CEMS PHI BETA KAPPA MEMBERS 1948-2019
Rebecca Caroline Osborn 2019 BSME Mechanical Enginering Colby J. Nadeau 2015 BSM Statistics and Mathematics Flora Kathleen Su 2015 BSEV Engineering Environmental Katherine Selby King 2014 BSM Statistics and Mathematics Stephen Alaster Thompson 2014 BSM Mathematics
OUT OF
AFRICA
BY SARAH TUFF DUNN
More than ever before, individuals and institutions are empowered to improve healthcare around the world— but often face systematic logistical obstacles. Up to 70 percent of donated medical devices, for example, end up unused in Africa, according to the World Health Organization.
That’s how CEMS students Jonathan Ferri ‘20 and Madeleine McGill ’21, landed summer experiences in Tanzania and Rwanda, respectively. As they recently presented to the CEMS Board of Advisors, the Engineering World Health Institute has matched the need for repaired medical devices in resource-poor communities with learning opportunities for students—resulting in lifechanging experiences for both sides.
A Transformative SEED Capstone
Ferri spent three months troubleshooting ultrasound machines, among other tasks, while learning Swahili and enjoying such Tanzanian customs as “taking chai,” a mid-morning break of mbege (banana and beef stew), which often inspired solutions. He returned with not only new skills but also a SEED capstone project of designing a prosthetic foot prototype. “This program allowed me to do everything I wanted,” he says, “and it all happened to be in Tanzania.”
Gratitude and Perspective
McGill, meanwhile, devoted her time to repairing infant incubators, oxygen concentrators and other medical equipment at two Rwandan hospitals, where she adjusted to what fi rst appeared to be a slow pace but really represented the people’s appreciation for life and the work the team was doing. “I gained a real gratitude for taking a step back,” she says. “I always thought that biomedical engineering innovation is a really cool, important, and growing fi eld, but I worry about our innovation increasing so much that it really only helps a small fraction of the world’s population.”
Now, thanks to these unique summer programs, CEMS students are learning how to overcome old obstacles and make a much broader impact worldwide.
View a video slideshow of Ferri and McGill's work in Tanzania and Rwanda at go.uvm.edu/7lua5."
ENGINEERING FOR SPEED
OGDEN WINS NCAA CHAMPIONSHIP Sophomore triumphs in 10-kilometer ski race
BY JOSHUA E. BROWN
Ben Ogden loves engines. “Jet engines, diesel engines, gas engines,” he says. “They’re fascinating.”
Last fall, in a two-semester thermodynamics class, he studied “all the math, calculating power outputs, and a lot of theory,” the engineering major says. “But this semester it’s applied thermodynamics and we’re learning how all the math applies in the real world, to real engines—which I love.”
Last spring, Ogden was taking some tough exams—in Germany. He was there training and racing with the U.S. Ski Team. “I’m on the U.S. D Team— which stands for development—it’s an under-23 team,” he explains, that allows him to both compete for UVM most of the season and the national team as well. One of the academic exams was in thermodynamics— issued by his UVM professor, William Louisos, and proctored by one of Ogden’s U.S. coaches. “It was really challenging, but I did well,” he says.
“I appreciate the challenge of engineering. That’s, honestly, a major draw for me,” Ogden says. “It's not easy and it forces me to push myself every day in school. A lot of times it’s incredibly frustrating and I have to kick myself to get through it—but then I look back at what I was doing at the beginning of the semester that was really hard and now it’s no problem—which I fi nd immensely satisfying.”
The other test was a series of races against many of the best young skiers in the world. Ogden fared well in several individual races and was part of the men’s 4x5 kilometer relay that won gold, defending their title in the Junior Cross Country World Championships by fi nishing 35 seconds ahead of Canada.
Like a well-trained engineer, Ogden approaches the problem of racing fast with a clear goal and a fl exible set of tools. “We’ve got a great UVM team and what I want to do is just ski as hard as I can and leave it all on the course—whether I feel good, bad or horrible,” he says.
Skiing shapes his plans for the future as well. “I do want to take a crack at a professional skiing,” says Ogden, who credits UVM Nordic coach Patrick Weaver—two-time national champion and former Olympian—with helping him to build a strong training plan and to dream big. “The Olympics are coming up in two years. That’s the dream,” Ogden says. And then he seems to correct himself. “That’s the reach goal,” he says.
And beyond that? Ogden is not sure. His skis are made by Madshus and he knows another young skier, who studied engineering, that the company hired to work on new skate ski designs. “That's the type of thing that I would love to do,” Odgen says, “to really get my hands dirty and design things.”
