Calendar of MRSEC Events

GRC Education Requirements: Undergraduates or those who have not obtained a bachelor's degree in science/engineering (or acceptable equivalent) are not eligible to apply to attend Gordon Research Conferences or Seminars.

Conference Description: The Colloidal, Macromolecular and Polyelectrolyte Solutions GRS provides a unique forum for young doctoral and post-doctoral researchers to present their work, discuss new methods, cutting edge ideas, and pre-published data, as well as to build collaborative relationships with their peers. Experienced mentors and trainee moderators will facilitate active participation in scientific discussion to allow all attendees to be engaged participants rather than spectators.

This meeting will focus on the connection between microstructure and macroscopic properties of complex fluids, highlighting approaches for characterizing and designing functional materials. Discussions will cover experimental and computational methods, as well as practical applications. Graduate students and post-doctoral researchers working in these areas are encouraged to apply and take part in this interactive and collaborative scientific exchange.

Application Information: Applications for this meeting must be submitted by January 3, 2026. Please apply early, as some meetings become oversubscribed (full) before this deadline. If the meeting is oversubscribed, it will be stated here. Note: Applications for oversubscribed meetings will only be considered by the conference chair if more seats become available due to cancellations.

More about the Bridging Microstructure and Functionality Seminar

Related Meeting: This GRC will be held in conjunction with the "Science of Soft Building Blocks for Functional Materials" Gordon Research Seminar (GRS) on February 1 - 6, 2026.

Related Meeting Description: Dispersions and solutions of colloids, macromolecules, or polyelectrolytes enable the development of functional materials for societally critical applications such as energy production and storage, controlled release, biomaterials, and environmental remediation. This GRC will feature talks that address exciting open questions in the fundamental science controlling the structure, dynamics, and emergent properties of these soft building blocks; the active, biomimetic, and/or learning processes by which they assemble in and out of equilibrium; and their use in advanced applications.

Those interested in attending both meetings must submit an application for the GRS in addition to an application for the GRC. Refer to the associated GRS program page for more information.
Application Information: Applications for this meeting must be submitted by January 4, 2026.

Abstract:When heartbeats become irregular due to tachycardia or fibrillation, spiral waves and motile defects emerge at the surface of cardiac tissues^[1]. Capturing the emergence of such defects in confluent tissues without any cellular flow is a theoretical challenge which has recently been tackled by models of actively deforming particles^[2-5]. In dense assemblies where particles are subject to individual pulsation of their sizes, the interplay between synchronization and repulsion can produce deformation waves resembling those observed in cardiac tissues. Combining particle-based and hydrodynamic approaches, we examine the statistics of defects in the collective deformation of particles. We rationalize the emergence of defect motility as stemming from the breakdown of time-reversal and spatial symmetries. Specifically, we provide analytical predictions for the deformation profile near the defect core to quantify the angular and translational velocities of defects. These results lead to identifying the dominant mechanism underlying the crossover between various deformation patterns in contractile tissues, with broader implications for understanding similar phenomena in other active systems.

[1] A. Karma, Annu. Rev. Condens. Matter Phys., 4, 313-337 (2013)
[2] Y. Zhang, É. Fodor, Phys. Rev. Lett., 131, 238302 (2023)
[3] A. Manacorda, É. Fodor, Phys. Rev. E, 111, L053401 (2025)
[4] W. Piñeros, É. Fodor, Phys. Rev. Lett., 134, 038301 (2025)
[5] T. Banerjee, et al., arXiv:2407.19955 (2024); arXiv:2509.19024 (2025)

More about the Soft Condensed Matter Seminar

Abstract: TBD

More about the Squishy Physics Seminar

What is different between a soap bubble in air and a bubble in liquid? How is folding an origami crane like closing an umbrella? What do windmills and bicycles have in common?

Bring your family to this year's Holiday Lecture for kids. Discover how everyday objects like bubbles and origami inspire scientific breakthroughs in health, energy, and technology. Enjoy hands-on experiments, interactive demonstrations, and activities that reveal how scientists explore the world. Recommended for children ages 7 and up. Children receive a free T-shirt.

More information about the 2025 Holiday Lecture, and registration is recommended.

Abstract: Particle suspensions can fracture into intricate patterns as they are pushed out of equilibrium. We probe the fracture and relaxation characteristics of dense aqueous cornstarch suspensions that exhibit discontinuous shear-thickening behavior. Air injection into three-dimensional bulk suspensions can lead to smooth bubbles that rise upwards under the action of buoyancy or to sharp fractures that remain attached to the injection nozzle. We link the shape and the relaxation dynamics of the air cavity to the suspension rheology. We discuss how the bubbles exhibit distinct bursting patterns as they reach the air interface, and how the bursting characteristics might reveal information about the rheology of thin suspension films. In a second example, we report the crack dynamics and morphology occurring as drops of aqueous nanoparticle suspensions evaporate on a glass surface and leave behind a solid particle deposit. We show that in the final stage of drying, the stresses in the deposit can be released in two distinct ways: by bending out of plane or by forming a second generation of cracks.

More about the Squishy Physics Seminar

Presenters: Mauro Colagreco (@maurocolagreco), chef-owner of Mirazur in Menton, France—ranked one of the best restaurants in the world—explores the next frontier of fermentation and flavor. His work with non-alcoholic and low-alcoholic drinks reflects his ongoing drive to push the boundaries of culinary creativity.

Abstract: To survive and function, living systems must robustly arrange biomolecules in space and time. This spatiotemporal organization of matter is achieved through a variety of passive and active processes, giving rise to emergent structures and patterns. In this talk, I will highlight two examples where we constructed continuum models to understand the emergence of patterns from microscopic interactions.

The first example is bacterial chromosome segregation. Unlike eukaryotes, bacteria such as Escherichia coli lack cytoskeleton-based machinery to segregate their chromosomal DNA (nucleoids). Still, E. coli faithfully segregates nucleoids across a wide range of growth rates. Here, we provide theoretical and experimental evidence that nonequilibrium phase separation driven by polysome production promotes chromosome segregation and couples its timing to overall biomass growth across nutritional conditions.

The second example is phase separation on biological membranes. Many condensates rely on membrane interactions for recruitment, localization, and biochemical substrates. Many of these interactions are mediated by membrane-anchored molecules such as proteins or specific lipids, which we refer to as “mobile tethers” since they can typically diffuse within the membrane while still interacting with the condensate. I will show that tethers can modulate condensate wetting, localization, and migration on membranes. If time permits, I will also discuss tether-mediated membrane prewetting.

More about the Soft Condensed Matter Seminar

Abstract: While photophoresis, or "light-driven motion," has long explained how aerosol layers remain aloft in the upper atmosphere, practical applications have only recently been gaining attention. Advances in nanofabrication now allow us to build devices that are much larger than aerosols but lightweight enough to propel themselves upward using photophoretic forces alone. These devices could sustain flight in near-space (30-100 km altitudes), a region of our atmosphere which is too high for aircraft and balloons to fly, but too low for satellites to orbit. I will discuss the physics of photophoresis, how it arises from temperature and material-property gradients on a surface, and recent experimental tests and models that demonstrate its viability for near-space propulsion. I will also outline potential applications, including atmospheric and space weather data collection, telecommunications, and exploring Mars’s atmosphere.

More about the Squishy Physics Seminar

Abstract:The talk will discuss the stability of flocking phases which exhibit symmetry breaking. For models which break a discrete symmetry, both an active Ising model and a hydrodynamic description will be used to show that droplets of particles moving in a direction opposite to that of the ordered phase nucleate and grow ballistically in all directions. The results imply that, in the thermodynamic limit, discrete-symmetry flocks are metastable in all dimensions. Following this the ordered phase of a flocking model which breaks a continuous symmetry will be considered and argued to be stable in parts of the phase diagram. This implies that in flocking models, in contrast to equilibrium systems, breaking a continuous symmetry is easier than a discrete one.

More about the Soft Condensed Matter Seminar

Abstract: In the search for simplicity in biology, many physicists have focused on microbial colonies as a model system for population growth and evolutionary dynamics. Indeed, minimal models often reproduce the linear increase of colony radius over time or the circular bulges formed by beneficial mutations. A more careful examination, however, reveals that microbial colonies are far more complex than these models suggest, due to a nontrivial interplay between physical and biological processes. I will describe our work to capture this interplay using phenomenological models of growth and competition based on generalized Fisher and Kardar-Parisi-Zhang equations. Our results explain previously observed growth laws and spatial patterns and provide novel experimentally testable predictions.

More about the Soft Condensed Matter Seminar

Abstract: How microtubules stay organized in living neuronal dendrites despite their intrinsic dynamic instability and stochastic variability remains a fundamental yet ongoing question in biology. It has been difficult to propose hypotheses due to a lack of in vivo, quantitative measurements within complex neuronal arbors. Here, we achieved direct measurements of microtubule dynamics, length, number, and tubulin partitioning using methodological pipelines that combine fly genetics, live-cell microscopy, and deep learning to permit in vivo analyses in Drosophila sensory neurons. We found microtubules are shorter and fewer near distal dendrites and become progressively longer and more numerous toward the primary dendrites. Altering tubulin levels modulates microtubule length and number while preserving the spatial distribution and polymer-free tubulin partitioning. A minimal physical model shows that these features emerge from dendritic branching and systematic tapering geometries. Our findings suggest complex microtubule organizations are governed by generic geometric rules that may confer evolutionary robustness and efficiency.

More about the Squishy Physics Seminar

Presenters: Martin Breslin (@HUDSinfo), Director of Culinary Operations for Harvard University Dining Services, oversees culinary standards and operations for five million meals annually, award-winning chef, awardee of multiple American Culinary Federation medals, founding member of Healthy Menus Collaborative.

Smitha Haneef (@HUDSinfo), Managing Director for Harvard University Dining Services, brings global culinary leadership and innovation in sustainable dining practices.

Abstract: Geometric frustration is most often associated with the disruption of long-range order and proliferation of defects in the bulk state of a self-organizing system. Held together by non-covalent finite-range interactions, assemblies in soft matter are able to tolerate some measure of local misfit due to frustration, allowing imperfect order to extend over at least some finite range. This talk focuses on theoretical frameworks for exploiting geometrically-frustrated assemblies (GFAs) to realize size-controlled, self-limiting assembly. While concepts of GFA have been used to describe a broad range of soft matter structures (e.g. self-twisting protein bundles, chiral membranes, spherical colloidal shells), current challenges focus on exploit GFA principles to design and realize new classes of intentionally ill-fitting subunits that target assembly into finite-size structures, with tunable and well-defined dimensions much bigger than those building blocks. In this talk, I describe some of the emerging principles and ongoing efforts to engineer the intra-assembly stress propagation and thermodynamic self-limitation in assemblies through the shape, interaction and flexibility of those building blocks. First, I describe attempts to understand the statistical mechanics of GFA based on a minimal based model. Finite temperature simulation and classical aggregation models applied this generic model illuminate how competing thermodynamic states of GFA—dispersion, self-limiting aggregation and bulk condensation—are regulated by the relative importance of elastic costs of frustration, short-range cohesion and entropy. Second, I describe efforts to intentionally design self-limiting assembly from a particle-scale properties of discretely ill-fitting subunits, motivated by a recent advances in shape-controlled DNA origami colloids. In particular, I will show how "programming self-limiting" size, requires more than just control over the shape misfit between subunits, but also engineering the nature of intra-subunit stress gradients in frustrated assemblies. In particular, the combination of geometric frustration with floppy-mechanical modes opens up the possibility of assemblies that can "sense" their size at especially long, super-particle size scales.

More about the Soft Condensed Matter Seminar

Abstract: Lipid nanoparticles (LNP) have emerged as pivotal delivery vehicles for mRNA vaccines, small interfering RNA (siRNA) therapeutics, and gene editing. Despite their proven efficacy and safety profiles, it has been challenging to reveal their payload packaging characteristics and assembly structures. This hinders efforts to design better gene delivery vehicles from structure-property-function perspectives. In this seminar, I will report an integrated spectroscopy–chromatography platform, coupling cylindrical illumination confocal spectroscopy (CICS) with single-nanoparticle free solution hydrodynamic separation (SN-FSHS), that can characterize loading levels of three (fluorescently tagged) cargos and the size of LNPs simultaneously, at the single-nanoparticle level and in a high-throughput manner. Using a benchmark LNP formulation, the platform demonstrates its capability by distinguishing seven LNP populations based on composition profiling, quantitatively characterizing size distribution and mRNA or siRNA loading level in wide ranges, and more interestingly, resolving composition-size correlations. From its output matrix, our team revealed presence of empty LNPs and potential mechanisms for their formation. We also found a significant degree of heterogeneity in cargo loading among LNP populations, contrasting common belief of uniform cargo loading. We analyze the kinetics-driven assembly process for LNPs and are using the learnings to direct further developments of LNP manufacturing processes with multiple industrial partners.

More about the Squishy Physics Seminar

Presenters: Bryan Furman (@bs_pitmaster), pitmaster and founder of Bryan Furman BBQ, has achieved national recognition for his smoking expertise and use of Heritage hogs, earning accolades such as Food & Wine Magazine’s 2019 Best New Chef and a James Beard Foundation semi finalist nomination, while continuing to expand his culinary empire with restaurants and pop-ups across the U.S. and Europe.

Presenters: Claire Saffitz (@csaffitz), pastry chef, YouTube host, and author of Dessert Person and What's for Dessert, is known for bringing pastry science to a wide audience. She received the IACP Julia Child Award in 2020 and was nominated for a James Beard Award in 2022.

Abstract: Cortical excitability, a phenomenon in which the cell cortex is dynamically patterned with waves of F-actin assembly, has been described in a variety of animal model systems, including embryos of mammals, flies, frogs and echinoderms, as well as a variety of cultured cells. While the cortical F-actin network is closely linked with the plasma membrane, it is not known if membrane composition or fluidity regulates dynamic cytokinetic patterning. Phospholipids partition within the plasma membrane during cytokinesis, and phosphoinositides play a key regulatory role in other excitable systems, suggesting a role for membrane-dependent regulation of cytokinetic patterning. Here we use an artificial reconstituted cell cortex comprised of Xenopus egg extract and supported lipid bilayers (SLBs) to show that membrane composition regulates self-organized cortical patterning. We find that manipulating levels of candidate lipids, including phosphatidylinositol 4,5-bisphosphate, phosphatidylethanolamine, sphingomyelin and cholesterol, results in both quantitative and qualitative changes in the dynamics of traveling waves and standing oscillatory patterns of active Rho and F-actin, as well as the kinetics of Rho activation and F-actin assembly on supported lipid bilayers. Our findings demonstrate that membrane composition directly regulates the assembly of cortical F-actin, as well as emergent active Rho and F-actin patterning.

More about the Squishy Physics Seminar

Abstract: Recent breakthroughs in experimental neuroscience and machine learning have opened new frontiers in understanding the computational principles governing neural circuits and artificial neural networks (ANNs). Both biological and artificial systems exhibit an astonishing degree of orchestrated information processing capabilities across multiple scales - from the microscopic responses of individual neurons to the emergent macroscopic phenomena of cognition and task functions. At the mesoscopic scale, the structures of neuron population activities manifest themselves as neural representations. Neural computation can be viewed as a series of transformations of these representations through various processing stages of the brain. The primary focus of my lab's research is to develop theories of neural representations that describe the principles of neural coding and, importantly, capture the complex structure of real data from both biological and artificial systems.

In this talk, I will present three related approaches that leverage techniques from statistical physics, machine learning, and geometry to study the multi-scale nature of neural computation. First, I will introduce new statistical mechanical theories that connect geometric structures that arise from neural responses (i.e., neural manifolds) to the efficiency of neural representations in implementing a task. Second, I will employ these theories to analyze how these representations evolve across scales, shaped by the properties of single neurons and the transformations across distinct brain regions. Finally, I will demonstrate how insights from the theories of neural representations can elucidate why certain ANN models better predict neural data, facilitating model comparison and selection.

More about the Soft Condensed Matter Seminar

Presenters: Nok Suntaranon (@kuhnnok / @kalayaphilly), chef-owner of Kalaya in Philadelphia, is the winner of the 2023 James Beard Award for Best Chef: Mid-Atlantic and a 2020 nominee for Best New Restaurant. Her vibrant Thai cooking has received national acclaim for its bold flavors and artistry.

Abstract: Electronics that can seamlessly integrate with human body could have significant impact in medical diagnostic, therapeutics. However, seamless integration is a grand challenge because of the distinct nature between electronics and human body. Traditional electronics, rigid and planar, face inherent mismatches with the soft, deformable nature of the human body. This presentation will introduce our solution to the challenge. Our approach, termed "rubbery electronics," relies on the use of elastic, rubbery materials for semiconductors, conductors, and dielectrics. These materials exhibit tissue-like softness and mechanical stretchability, enabling seamless integration with soft, deformable tissues and organs. The presentation will highlight the development of rubbery materials, particularly the nanocomposite semiconductors engineered to balance carrier mobility and mechanical stretchability – as the foundation for rubbery electronics. Building on these materials, this presentation will also showcase our advances in electronics, sensors, and functional systems and their applications in healthcare, robotics, and human-machine interfaces. As a platform technology, rubbery electronics not only overcome longstanding challenges in biointegration but also open broad opportunities for innovation, promising significant impact across diverse scientific and technological frontiers.

Biosketch: Dr. Cunjiang Yu is the Founder Professor at the University of Illinois Urbana-Champaign in the Department of Electrical and Computer Engineering, also holds joint appointments in the Departments of Materials Science and Engineering, of Mechanical Science and Engineering, and of Bioengineering. His research focuses on the fundamentals and applications of soft and bio electronics. Dr. Yu work has been recognized with many honors, including multiple Young Investigator Awards from the ASME, Society of Engineering Science, American Vacuum Society, ONR, as well as the NSF CAREER Award, the NIH Trailblazer Award, and recognition as an MIT Technology Review Innovator under 35.

More about the Squishy Physics Seminar

Presenters: Lars Williams (@empiricalspirits), co-founder of Empirical Spirits, has been internationally recognized for innovation in flavor and distillation. Empirical Spirits earned Double Gold, Silver, and Bronze medals at the 2023 San Francisco World Spirits Competition.

About: The STEAM event of the year, a family-friendly science extravaganza with an afternoon of education and entertainment, with over 100 STEAM-themed activities for innovation-enthusiasts of all ages.

Presenters: Joanne Chang '91 (@jbchang), James Beard Award–winning pastry chef and restaurateur, is the co-owner of Flour Bakery + Café and Myers + Chang in Boston. She is also the author of several acclaimed cookbooks, including Flour, Flour Too, Baking with Less Sugar, and Myers + Chang at Home.

Presenters: Dave Arnold (@CookingIssues), founder of Booker and Dax (NYC), author of Liquid Intelligence, host of the podcast Cooking Issues, and founder of the Museum of Food and Drink, is known for his groundbreaking work at the intersection of culinary innovation and science.
Harold McGee (@Harold_McGee), celebrated food science writer and author of On Food and Cooking, Curious Cook, and Nose Dive: A Field Guide to the World's Smells, has shaped the way chefs and home cooks understand the chemistry of food.

Abstract: Dr. Eric Darling is an Associate Professor of Medical Science, Engineering, and Orthopaedics in the Department of Pathology and Laboratory Medicine at Brown University and a core member of its Institute for Biology, Engineering, and Medicine (I-BEAM). His seminar focuses on the development and application of multiple tools for characterizing the mechanical properties of cells and tissues. Specific attention will be given to the development of physiological cell mimics and their use as calibration particles for a novel multimodal mechanophenotyping cytometer. Early results on the functionality of this device for cell measurements will also be presented. In addition to characterizing the mechanical properties of single-cells, the Darling Lab also investigates microenvironmental forces in developing neotissues. This is done using the same calibration particles, although in this implementation, their deformation is visualized and equated to the applied forces from neighboring cells and tissue. Initial work has focused on changes in microenvironmental forces as adipose-derived stem cells self-assemble and compact into spheroids, modelling early stages of the mesenchymal condensation process. More recent findings have scaled up the testing platform to examine the influence of multiple force probe characteristics on mechanical measurements, with recommendations for their application to other experimental systems, and feasibility experiments investigating how these sensors can be used to explore in situ mechanical forces within larger neotissues.

More about the Squishy Physics Seminar

Abstract: Cancer is the second leading cause of death in the United States. This is due to the rapid growth rates of tumors, their ability to develop resistance to chemotherapy, and the difficulties in transporting therapeutics across vascular barriers and into surrounding tumor tissues. The lack of physiologically relevant in vitro human tumor models and the challenges in translating results from animal experiments to the clinic have greatly hindered progress in improving patient outcomes. To address this critical need, we employ novel design strategies to engineer in vitro microfluidic cancer models and 3D tumor models from patient tissues. These platforms enable us to study tumor development, design new targeted therapies for cancer, and understand the genetic mechanisms of resistance to chemotherapy. Our human-like tissue engineering models provide highly relevant pre-clinical tools that can be used to understand tumor progression and drug delivery, leading to better cancer patient outcomes.

Speaker Bio: Cynthia Hajal joined the Department of Mechanical and Industrial Engineering at Northeastern University in August 2023. Her lab focuses on the design of tissue engineered models of tumors to study cancer progression, drug delivery, and treatment resistance. She received a BA in Economics and BS in Mechanical Engineering from Columbia University and her SM and PhD in Mechanical Engineering from MIT. Her doctoral work focused on the design of microfluidic models of the vasculature to investigate cancer metastasis and molecular transport between blood and tissues. Prior to joining Northeastern University, she was a postdoctoral research fellow at the Dana-Farber Cancer Institute and Broad Institute of MIT and Harvard where she investigated resistance mechanisms to chemotherapies in patient-derived glioma tumor models using functional genomic screens. She was awarded the Lion’s Pride Young Alumni Award by Columbia University (2025) and was selected as a Featured Junior Investigator by the American Association for Cancer Research (2024) and a Rising Star in Mechanical Engineering by MIT (2021).

More about the Squishy Physics Seminar

Abstract: Surface and interfacial tensions play key roles in governing the mechanics of highly compliant materials, from traditional fluid capillary mechanics to the emerging field of elastocapillary mechanics of very soft solids. Our work studies the role of surface tension in a variety of contexts, from competing with elasticity in establishing adhesive contacts with soft polymer gels to driving surface instabilities and fracture on fluid surfaces to facilitating plant reproduction. In this talk, I will focus on our work investigating a dual role for capillarity—both solid and liquid—in adhesion with soft polymer gels. By varying parameters such as asperity size, adhesion energy, and gel material properties, we gain insight into the fundamental physical processes that dominate soft contact with rough surfaces across length and time scales. Second, I will introduce some of the intriguing fluid surface mechanics that we observe in our lab, from capillary multipole interactions harnessed by Marchantia polymorpha primitive land plants during their asexual reproduction to symmetric starburst fracture on a protein-laden fluid surface. Our experiments combine mechanical manipulation and force measurements with sensitive, high-speed 2D and 3D optical imaging to measure soft interface mechanics in both static and dynamic contexts.

More about the Soft Condensed Matter Seminar

Abstract: Engineers design structures to predictably resolve forces and moments through a primary load path in which deformations are small and linear. There is an enormous opportunity to design structures that rely on nonlinearities and instabilities to perform advanced functions and propagate forces in nontrivial ways. This talk will demonstrate how the complex mechanics of coupled nonlinear structures can create novel actuators, artificial muscles, soft robotic grippers, and perform rudimentary mechanical computation. I will begin by discussing the nonlinear deformations of beams bending together as they pack and compete for space. Then I will discuss how engineering defects into thin sheets provides a way to control how they deform. Typical defects include folds(origami) and cuts (kirigami), and I will describe how these defects enable the design of functional mechanical metamaterials. Lattice cuts provide a simple way to enhance the stretchability of a thin sheet. We show that certain lattice configurations are more stretchable than others, while certain configurations produce an array of bistable unit cells. The bistability provides a means to tune the stiffness of the structure in situ, while also providing a means for mechanical logic. Lattice cuts on curved sheets, i.e. kirigami shells, enable additional functionality. The natural curvature of the sheet causes the bistable lattices to curve together and close around an object, which enables the kirigami shells to act as soft robotic grippers. We will discuss the optimal kirigami geometry for a robotic gripper, and describe how the structures perform at both grasping and holding irregular objects. Finally, by coupling transmissive, multistable shells we developed universal logic gates, (NAND, NOT, XNOR), and combine them to demonstrate basic mechanical computation: binary addition via a half adder mechanical circuit.

More about the Soft Condensed Matter Seminar

Abstract: The biomechanical properties of neuronal cells are critical to their development, function, and structural stability. These properties influence cytoskeletal organization, axonal growth, and the formation of functional synapses. While substantial progress has been made in understanding neuronal growth and connectivity, a complete picture of axonal dynamics—incorporating the mechanical interactions between neurons and their environment—is still lacking. In this talk, I will present an integrated experimental platform that combines three high-resolution techniques: atomic force microscopy, fluorescence imaging, and traction force microscopy. Using this experimental setup, we measure the elastic modulus of cortical neurons with high spatial resolution and correlate these measurements with the traction forces generated by axons on their substrate. We also track cytoskeletal components to connect axonal behavior with changes in cytoskeletal dynamics, cellular volume, and cell biomechanical properties. In addition, I will discuss biomechanical measurements performed on human leukemia monocytic (THP-1) cells encapsulated in silk fibroin biomaterials. These results offer valuable insights for designing advanced biomaterial interfaces aimed at enhancing cellular protection and functional integration.

More about the Squishy Physics Seminar

Abstract: Chemical cues mediate interactions between marine phytoplankton and bacteria, underpinning ecosystem-scale processes including nutrient cycling and carbon fixation. Specifically, viral infection alters phytoplankton metabolism, stimulating the release of chemical cues, but how this process influences ecology and biogeochemistry is poorly understood. Here, we determine the impact of viral infection on dissolved metabolites from marine cyanobacteria and the subsequent chemotactic response of heterotrophic bacteria. We developed a novel microfluidic device for high-throughput bacterial chemotaxis screening, which - together with time-resolved metabolomics - proved essential to disentangle the roles of diverse chemical compounds in this process. Our results show that metabolites released from intact, virus-infected cyanobacteria elicit strong chemoattraction from heterotrophic bacteria, especially during early infection stages prior to lysis. Ultimately, these findings establish a new mechanism for resource transfer that might impact carbon and nutrient fluxes across trophic levels.

More about the Squishy Physics Seminar

Abstract: Human influenza viruses, as well as SARS-CoV-2, undergo fast evolution driven by immune pressure of their hosts. Viral strains and our immune systems are a tightly coupled, fast-evolving ecosystem. Fitness models have become an important tool to predict these dynamics and to guide the selection of vaccine strains. In this talk, I present the cross-scale concepts of current predictions: changing molecular interactions of viral proteins and human antibodies affect immune protection, generate time-dependent fitness differences between strains, and shape the global evolution of the pathogen. This analysis contains building blocks of a new, computable framework for human adaptive immunity.

More about the Squishy Physics Seminar

Abstract: Identifying effective immunization schemes against highly mutable pathogens such as HIV and influenza viruses remains a persistent public health challenge. Our work addresses this challenge by analyzing a simplified model of affinity maturation, the Darwinian evolutionary process that B cells undergo during immunization.

In this presentation, I will introduce a minimal framework that identifies optimal selection forces exerted by time-dependent vaccination protocols. This framework aims to maximize the production of broadly neutralizing antibodies (bnAbs) that can protect against a broad spectrum of pathogen strains. The model utilizes a path integral representation within a mean-field limit to provide guiding principles for optimizing vaccine-induced selection forces. Additionally, I will discuss our ongoing research that extends this theoretical framework to more complex immunological scenarios. This extension employs regression algorithms to derive simplified dynamical equations from time series data generated by agent-based and population simulations. These equations effectively capture the evolution of B cell populations and antibody responses, providing valuable insights into antigen competition and other nonlinear effects that emerge from the complex feedback mechanisms of immunological memory.

More about the Soft Condensed Matter Seminar

Abstract: Nature has developed diverse adhesion strategies, from mussel-inspired underwater glues to gecko-like dry adhesion. Silk fibroin, with its tunable structure and exceptional mechanical properties, provides a versatile foundation for bioinspired adhesives. This seminar examines key natural adhesion mechanisms and how silk fibroin can be engineered into various material formats to create functional adhesives. By leveraging its unique properties, silk-based adhesives can be tailored for applications ranging from underwater adhesion to biodegradable labeling and even superhero inspired adhesives.

More about the Squishy Physics Seminar

Abstract: The towering successes of twentieth century theoretical physics were marked by two guiding principles: symmetry and energy functionals (reflecting equilibrium dynamics). Yet how we can exploit these principles to develop a theory of living systems is unclear since the biological world is composed of heterogeneous, interacting components operating out of equilibrium. In this talk, I will argue that one possible strategy for taming biological complexity is to embrace the idea that many biological behaviors we observe are “typical” and can be modeled using random systems that respect biologically-inspired constraints. I will focus on high-dimensional ecology and show how we can use tools from statistical physics (cavity method, DMFT) to understand the emergence of chaos in the ecosystems with non-reciprocal interactions.

More about the Soft Condensed Matter Seminar

Abstract: In this talk, we study a minimal model of a system with coexisting nematic and polar orientational orders, where one field tends to order and the other prefers isotropy. For strong coupling, the ordered field aligns the isotropic one, locking their orientations. The phase diagram reveals three distinct phases—nematopolar (aligned orders), nematic (independent orders), and isotropic (vanishing orders)—separated by continuous and discontinuous transitions, including a triple and a tricritical point. We find unique critical scaling for the nematopolar-nematic transition, distinct from standard nematic or polar universality classes. Additionally, in the locked nematopolar phase, we show nematic +1/2 topological defect pairs are connected and confined by strings with constant tension. These strings arise from frustration in locking the orientational orders and can be interpreted as elongated cores of +1 polar topological defects. When a sufficiently strong background field couples to the polar order, all topological defects are expelled from the region. Analytical predictions are quantitatively confirmed by numerical simulations. Based on joint work with Amin Doostmohammadi.

More about the Soft Condensed Matter Seminar