Events
Past Event
WED@NICO WEBINAR: Lightning Talks with Northwestern Fellows and Scholars!
Northwestern Institute on Complex Systems (NICO)
12:00 PM
Details
Description:
NICO is hosting a lightning talk seminar each term as a part of our Wednesdays@NICO seminar series. Northwestern graduate students and postdoctoral fellows are invited to participate. To sign up for future lightning talks, please visit: https://bit.ly/2lRqSXK
Webinar:
Webinar link: https://northwestern.zoom.us/j/96018513447
Passcode: nico
ID: 960 1851 3447
Speakers:
Jaehyuk Park
Postdoctoral Fellow
Kellogg School of Managmeent, and
Northwestern Institute on Complex Systems
Emma Zajdela
PhD Candidate
Department of Engineering Sciences and Applied Mathematics
McCormick School of Engineering
Gary Nave
Postdoctoral Fellow
Department of Engineering Sciences and Applied Mathematics
McCormick School of Engineering
Sarah Ben Maamar
Postdoctoral Fellow
Department of Chemical and Biological Engineering
McCormick School of Engineering
Talk Titles and Abstracts:
Jaehyuk Park "People, Places, and Ties: Landscape of social places and their social network structures"
Due to their essential role as places for socialization, “third places”—social places where people casually visit and communicate with friends and neighbors—have been studied by a wide range of fields including network science, sociology, geography, urban planning, and regional studies. However, the lack of a large-scale census on third places kept researchers from systematic investigations. Here we provide a systematic nationwide investigation of third places and their social networks, by using Facebook pages. Our analysis reveals a large degree of geographic heterogeneity in the distribution of the types of third places, which is highly correlated with baseline demographics and county characteristics. Certain types of pages like “Places of Worship” demonstrate a large degree of clustering suggesting community preference or potential complementarities to concentration. We also found that the social networks of different types of social place differ in important ways: The social networks of ‘Restaurants’ and ‘Indoor Recreation’ pages are more likely to be tight-knit communities of pre-existing friendships whereas ‘Places of Worship’ and ‘Community Amenities’ page categories are more likely to bridge new friendship ties. We believe that this study can serve as an important milestone for future studies on the systematic comparative study of social spaces and their social relationships. This is joint work with Bogdan State (scie.nz), Monica Bhole (Facebook), Michael Bailey (Facebook), and Yong-Yeol Ahn (Indiana Univ.).
Emma Zajdela "Catalyzing Collaborations: A Model for the Dynamics of Team Formation at Conferences"
The COVID-19 pandemic has brought to the fore the importance of collaboration among scientists to address challenges of global significance. One of the main ways that new and innovative collaborations are catalyzed is by gathering scientists together at conferences. In the U.S. alone, conferences amount to billions of dollars per year in terms of travel expenses, organizing costs, and loss of research time. In this lightning talk, I present a dynamical model for predicting the formation of scientific collaborations at conferences, inspired by the chemical process of catalysis. Specifically, the model tracks the probability that two participants at a conference will form a collaboration given their previous knowledge of each other and level of interaction throughout the conference. Model predictions are tested using data from two multi-year series of interactive conferences known as the Scialog Conferences, organized by the Research Corporation for Science Advancement over the period 2015-2020. We find that scientists who interact more intensely throughout the conference have a higher likelihood of forming a collaboration. Furthermore, we find that the likelihood of collaborating remains at a higher level even after the interaction between participants has ceased. Our findings may have an impact on stakeholders from public, private, and nonprofit sectors who wish to optimize future conferences to promote new collaborations.
Gary Nave "Approximating attracting and repelling flow features with the trajectory divergence rate"
Within the flow of a fluid or a dynamical system, there are often attracting or repelling manifolds that provide an organizing “skeleton” to the flow. These structures have been shown to be barriers to transport of material moving within a flow. In this talk, I will introduce the trajectory divergence rate, which can serve to rapidly approximate attracting and repelling structures using only the vector field. By looking at the instantaneous growth rate of normal vectors, we measure the rate at which adjacent trajectories are coming together or moving apart. This diagnostic can be applied to, for example, slow manifolds, ocean flows, and limit cycle oscillations, and provides an intuitive understanding of the geometric organization of a flow.
Sarah Ben Maamar "Comprehensive analysis of the reproducibility of RNAseq computational pipelines"
Sarah Ben Maamar, Reese Richardson, Sophia Liu, Luis Nunes A. Amaral.
Next generation sequencing technologies revolutionized biomedical research and became unavoidable due to their low costs, high amount of data generated and the wide variety of their applications. In particular, RNA-sequencing (RNA-seq) has become widely used in biological and biomedical fields as this technique allows the evaluation of gene expression levels in model organisms under different contexts. These contexts include the comparison of sick versus healthy cells; the effect of specific drugs on cells gene expression; monitoring of changes in gene expression over time; or the discovery of the potential role of an unknown gene when comparing different tissues.
As the output of RNA-seq is complex and large, processing and analysis of such data requires the use of complex computational pipelines involving multiple steps and softwares to make the data comprehensible. RNA-seq computational pipelines vary according to the application and can have up to six steps, for which up to ten different softwares are available for each task. Each software also offers multiple parameters to better tune the analysis for each application and dataset.
Despite the endless choices, there is currently no standardized pipeline agreed upon in the broad biomedical field. Thus, unless a computational pipeline used to process a dataset is thoroughly documented, it is almost impossible to reproduce the results obtained from a dataset after processing.
In this work, we analyze the documentation and replicability associated to each step of RNA-seq computational pipelines used to study differential gene expression in the model bacteria Escherichia coli. We particularly assess the intrinsic bias introduced by the use of each software for each step as well as the bias associated to each parameter choice. Interestingly, we found two to three steps of RNA-seq computational pipeline are particularly undermining the comparability of the results between studies. We are currently in the process of quantifying the biases at each step of the different computational pipelines and this talk will present some of our results.
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems and data science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, March 3, 2021 at 12:00 PM - 1:00 PM
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Simbarashe Nkomo, Emory University "Exploring the Emergence of Complex Dynamics in Networks of Belousov-Zhabotinsky Oscillators"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
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Lower Level, Chambers Hall
Details
Speaker:
Simbarashe Nkomo, Assistant Professor of Chemistry, Oxford College of Emory University
Title:
Exploring the Emergence of Complex Dynamics in Networks of Belousov-Zhabotinsky Oscillators
Abstract:
TBA
Speaker Bio:
Simbarashe Nkomo is an Assistant Professor of Chemistry at Oxford College of Emory University. His research interests include the synchronization behavior in networks of coupled chemical oscillators. He received his Ph.D. in Chemistry from West Virginia University in 2014 and a Master of Science from the University of Zimbabwe in 2007.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/97359095225
Passcode: NICO2024
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, April 24, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
NICO AI Seminar: Ziv Epstein, Stanford University "Re-Inventing the Attention Machine"
Northwestern Institute on Complex Systems (NICO)
1:00 PM
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Lower Level, Chambers Hall
Details
Speaker:
Ziv Epstein, Postdoctoral Fellow, Stanford Institute for Human-Centered AI, Stanford University
Title:
Re-Inventing the Attention Machine
Abstract:
Modern AI systems - such as LLMs and feed algorithms on social media - are algorithmic amplifiers that uplift certain voices and perspectives. But whose perspectives? In this talk, I will argue that human attention is the key bridge to understanding how we shape these AI amplifiers and how they shape us. In particular, I will argue that AI systems are training on a particular ground truth that is mediated by human attention and as a result is hill-climbing on attentional noise. To what extent is training data transformed by attention? Can we measure it? And can we shift attention to make more deliberate training data? I will discuss ways to measure attentional drift in AI systems, as well as prosocial tools to align behavior and values, and ongoing attempts to embed values into these AI amplifiers explicitly. These projects point to a new way of designing sociotechnical systems for prosocial outcomes, by moving away from attention economies and towards attention ecologies.
Speaker Bio:
Ziv Epstein is a Postdoctoral Fellow at the Stanford Institute for Human-Centered AI. In his research, he focuses on translating insights from design and the social sciences into the development of sociotechnical systems such as generative AI and social media platforms. Ziv has published papers in venues such as the general interest journals Nature, Science and PNAS , as well as top-tier computer science proceedings such as CHI and CSCW. His work has also received widespread media attention in outlets like the New York Times, Scientific American, and NPR.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/98518429787
Passcode: NICO2024
Calendar:
Add to Outlook | Google Calendar
About this Seminar:
NICO welcomes everyone to join us at this AI focused Thursday afternoon seminar. Please note, since this is at 1pm, we provide light refreshments only.
Time
Thursday, April 25, 2024 at 1:00 PM - 2:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Chris Bail, Duke University "Bridging Divides with Generative AI"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Chris Bail, Professor of Sociology, Political Science, and Public Policy, Duke University
Title:
Bridging Divides with Generative AI
Abstract:
Political discourse is the soul of democracy, but misunderstanding and conflict can fester in divisive conversations. The widespread shift to online discourse exacerbates many of these problems and corrodes the capacity of diverse societies to cooperate in solving social problems. Scholars and civil society groups promote interventions that make conversations less divisive or more productive, but scaling these efforts to online discourse is challenging. This talk will describe a large-scale experiment that demonstrates how online conversations about divisive topics can be improved with AI tools. Specifically, my colleagues and employ a large language model to make real-time, evidence-based recommendations intended to improve participants’ perception of feeling understood. These interventions improve reported conversation quality, promote democratic reciprocity, and improve the tone, without systematically changing the content of the conversation or moving people’s policy attitudes. These findings replicate during a half year experiment on a large social media platform.
Speaker Bio:
Chris Bail is Professor of Sociology, Political Science, and Public Policy at Duke University, where he founded the Polarization Lab. He studies how artificial intelligence shapes human behavior in a range of different settings—and social media platforms in particular. Chris is passionate about building the field of computational social science. He is the Editor of the Oxford University Press Series in Computational Social Science and the Co-Founder of the Summer Institutes in Computational Social Science. Chris received his PhD from Harvard University in 2011.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/97722631639
Passcode: NICO2024
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, May 1, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Daniel Harris, Brown University "At the interface: physical analogy with interfacial fluid mechanics"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Daniel Harris, Assistant Professor of Engineering, Brown University
Title:
At the Interface: Physical Analogy with Interfacial Fluid Mechanics
Abstract:
Maxwell describes physical analogy as a "partial similarity between the laws of one science and those of another which makes each of them illustrate the other." Hydrodynamics has long since been a source of physical analogy, sharing similar equations with other seemingly disparate fields of physics. The focus of this talk will be on physical analogies with interfacial fluid systems, where accessible tabletop experiments can be used to investigate and communicate physical phenomena at vastly different scales. Following a brief review of some historical examples of analogy in interfacial fluid mechanics, I will describe two recent tabletop experiments developed in our lab that share similarities with certain microscopic colloidal systems. While physical analogy can be fruitfully used to advance science across disciplines, it can also be leveraged to enhance scientific communication and pedagogy.
Speaker Bio:
Daniel M. Harris is an Assistant Professor of Engineering at Brown University in the Fluids and Thermal Sciences group. Before joining Brown, Dan was a Postdoctoral Research Associate and Lecturer at the University of North Carolina at Chapel Hill in the Department of Mathematics. Dan received his B.S. in Mechanical Engineering from Cornell University in 2010 and his Ph.D. in Applied Mathematics from MIT in 2015.
Dan’s primary research interests are in interfacial phenomena, microfluidics, and transport phenomena. His research involves an integrated experimental and theoretical approach. Dan has also received numerous awards for his scientific visualizations, including being selected as the winner of the 2016 NSF/Popular Science Visualization Challenge in Photography, as well as numerous prizes from the American Physical Society’s Gallery of Fluid Motion and Gallery of Soft Matter.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/93585934682
Passcode: NICO2024
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, May 8, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Eleni Katifori, University of Pennsylvania "TBA"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Eleni Katifori, Associate Professor, Department of Physics & Astronomy, University of Pennsylvania
Title:
TBA
Abstract:
TBA
Speaker Bio:
Eleni Katifori is an Associate Professor in the Department of Physics & Astronomy, University of Pennsylvania. Prof Katifori’s research group are interested in understanding the physics behind the morphological and functional attributes of living organisms. They primarily focus on questions inspired by and related to biological transport networks and the elasticity and geometry of thin sheets. Professor Katifori received her Ph.D from Harvard University in 2008 and a B.S. from the University of Athens, Greece in 2002.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/92857810876
Passcode: NICO2024
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, May 15, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Serguei Saavedra, MIT "How Do Ecological Systems Become (re)Assembled?"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
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Lower Level, Chambers Hall
Details
Speaker:
Serguei Saavedra, Associate Professor, Department of Civil and Environmental Engineering, MIT
Title:
How Do Ecological Systems Become (re)Assembled?
Abstract:
One of the most iconic thought experiments in biology is what would happen if we could rewind the tape of life on Earth and play it again. Would the tape have a different story in every replay? Or is there a general order of events? The relevance of this thought experiment is not just philosophical or counterfactual, because (re)assembly processes undergone by ecological systems, from microbes to mega-fauna, are continuously replicating the experiment. By integrating theoretical and empirical work, in this talk I will provide a guideline to increase our understanding about the (re)assembly possibilities of ecological systems. Explaining and predicting the (re)assembly of ecological systems underpins our ability to develop successful interventions in bio-restoration, bio-technologies, and bio-medicine.
Speaker Bio:
Serguei Saavedra is an Associate Professor at MIT in the Department of Civil and Environmental Engineering. He is also an external faculty at Santa Fe Institute. Serguei is a theoretical ecologist focused on understanding the feasibility of observing the emergence, transformations, and regeneration of ecological systems under environmental changes. Before joining MIT in 2016, Serguei studied systems engineering in Mexico; specialized in mathematical modeling at Genoa University; completed his PhD in engineering science at Oxford University; and did his postdoctoral work at the NICO (under the mentorship of Brian Uzzi), Doñana Biological Station, and in the department of environmental systems at ETH.
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/91082510906
Passcode: NICO2024
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, May 22, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)
WED@NICO SEMINAR: Joseph Paulsen, Syracuse University "TBA"
Northwestern Institute on Complex Systems (NICO)
12:00 PM
//
Lower Level, Chambers Hall
Details
Speaker:
Joseph Paulsen, Associate Professor, Department of Physics, Syracuse University
Title:
TBA
Abstract:
TBA
Speaker Bio:
Joseph Paulsen earned a bachelor's degrees in Mathematics and Physics from St. Olaf College in Northfield, MN, and he completed his PhD in Physics at the University of Chicago with Sidney Nagel. He won a National Science Foundation CAREER Award for his work that studies connections between geometry and mechanics in thin materials. Outside of science, one of his passions is trying to squirrel away as much time as possible to ski with his 7-year-old daughter (his son and his wife are not skiers... yet).
Location:
In person: Chambers Hall, 600 Foster Street, Lower Level
Remote option: https://northwestern.zoom.us/j/94291553667
Passcode: NICO2024
About the Speaker Series:
Wednesdays@NICO is a vibrant weekly seminar series focusing broadly on the topics of complex systems, data science and network science. It brings together attendees ranging from graduate students to senior faculty who span all of the schools across Northwestern, from applied math to sociology to biology and every discipline in-between. Please visit: https://bit.ly/WedatNICO for information on future speakers.
Time
Wednesday, May 29, 2024 at 12:00 PM - 1:00 PM
Location
Lower Level, Chambers Hall Map
Contact
Calendar
Northwestern Institute on Complex Systems (NICO)