http://s.uconn.edu/meseminar12/10/21

Abstract: Hydrogels, highly hydrated cross-linked polymer networks, have emerged as powerful synthetic analogs of extracellular matrices for basic cell studies as well as promising biomaterials for regenerative medicine applications. A critical advantage of these synthetic matrices over natural networks is that bioactive functionalities, such as cell adhesive sequences and growth factors, can be incorporated in precise densities while the substrate mechanical properties are independently controlled. We have engineered poly(ethylene glycol) [PEG]-maleimide hydrogels for local delivery of therapeutic proteins and cells in several regenerative medicine applications. For example, synthetic hydrogels with optimal biochemical and biophysical properties have been engineered to direct human stem cell-derived intestinal organoid growth and differentiation, and these biomaterials serve as injectable delivery vehicles that promote organoid engraftment and repair of intestinal wounds. In another application, hydrogels presenting immunomodulatory proteins induce immune acceptance of allogeneic pancreatic islets and reverse hyperglycemia in models of type 1 diabetes. Finally, injectable hydrogels delivering anti-microbial proteins eradicate bone-associated bacterial infections and support bone repair. These studies establish these biofunctional hydrogels as promising platforms for basic science studies and biomaterial carriers for cell delivery, engraftment and enhanced tissue repair.

Biographical Sketch: Andrés J. García is the Executive Director of the Petit Institute for Bioengineering and Bioscience and Regents’ Professor at the Georgia Institute of Technology. Dr. García’s research program integrates innovative engineering, materials science, and cell biology concepts and technologies to create cell-instructive biomaterials for regenerative medicine and generate new knowledge in mechanobiology. This cross-disciplinary effort has resulted in new biomaterial platforms that elicit targeted cellular responses and tissue repair in various biomedical applications, innovative technologies to study and exploit cell adhesive interactions, and new mechanistic insights into the interplay of mechanics and cell biology. In addition, his research has generated intellectual property and licensing agreements with start-up and multi-national companies. He is a co-founder of 3 start-up companies (CellectCell, CorAmi Therapeutics, iTolerance). He has received several distinctions, including the NSF CAREER Award, Young Investigator Award from the Society for Biomaterials, Georgia Tech’s Outstanding Interdisciplinary Activities Award, the Clemson Award for Basic Science from the Society for Biomaterials, the International Award from the European Society for Biomaterials, and Georgia Tech’s Class of 1934 Distinguished Professor Award. He is an elected Fellow of Biomaterials Science and Engineering (by the International Union of Societies of Biomaterials Science and Engineering), Fellow of the American Association for the Advancement of Science, Fellow of the American Society of Mechanical Engineers, and Fellow of the American Institute for Medical and Biological Engineering. He served as President for the Society for Biomaterials in 2018-2019. He is an elected member of the National Academy of Engineering, the National Academy of Medicine, and the National Academy of Inventors.

http://s.uconn.edu/meseminar12/3/21

Abstract: Internet of things (IoT), robotics, big data and artificial intelligence (AI) hold the key to Industry 4.0, which is identified as cyber-physical systems. To stay relevant in the AI age, humans must collaborate with robots or even merge with electronics and machines to realize internet of health (IoH), augmented reality (AR), and augmented human capabilities. However, bio-tissues are soft, curvilinear and dynamic whereas conventional electronics and machines are hard, planar, and rigid. Over the past two decades, soft electronics blossom as a result of new materials, novel structural designs, and digital manufacturing processes. This talk will discuss our research on the design, fabrication, conformability, and functionality of soft bio-integrated and bio-mimetic electronics based on inorganic functional materials such as metals, silicon, carbon nanotubes (CNT), and graphene. In particular, epidermal electronics, a.k.a. electronic tattoos (e-tattoos) represent a class of noninvasive stretchable circuits, sensors, and stimulators that are ultrathin, ultrasoft and skin-conformable. My group has invented a dry and freeform “cut-solder-paste” method for the rapid prototyping of multimodal, wireless, or very large area e-tattoos that are also high-performance and long-term wearable. The e-tattoos can be applied for physiological sensing and prosthesis/robot control. Recently, we have also engineered e-skins based on electrically conductive porous nanocomposite. The hybrid piezoresistive and piezocapacitive responses of this novel e-skin has enabled high pressure sensitivity over wide pressure ranges. It therefore could be applied for not only mechanophysiological sensing, but also soft robotics undergoing large deformations. A perspective on future opportunities and challenges in this field will be offered at the end of the talk.

 Biographical Sketch: Dr. Nanshu Lu is currently Temple Foundation Endowed Associate Professor at the University of Texas at Austin. She received her B.Eng. from Tsinghua University, Beijing, Ph.D. from Harvard University, and then Beckman Postdoctoral Fellowship at UIUC. Her research concerns the mechanics, materials, manufacture, and human / robot integration of soft electronics. She has been named 35 innovators under 35 by MIT Technology Review (TR 35). She has received US NSF CAREER Award, US ONR and AFOSR Young Investigator Awards, 3M non-tenured faculty award, and iCANX/ACS Nano Inaugural Rising Star Lectureship. She has been selected as one of the five great innovators on campus and five world-changing women at the University of Texas at Austin. She is named a highly cited researcher by Web of Science. For more information, please visit Prof. Lu’s research group webpage at https://sites.utexas.edu/nanshulu/.

http://s.uconn.edu/meseminar11/12

Abstract: This talk presents a manufacturability-driven, multi-component topology optimization (MTO) framework for simultaneous design and partitioning of structures assembled of multiple components. Constraints on component geometry imposed by chosen manufacturing processes are incorporated in the conventional density-based topology optimization, with additional design variables specifying fractional component membership that enables continuous relaxation of otherwise discrete partitioning problems.  The geometric constraints imposed by various manufacturing processes, such as size, perimeter length, undercut, and enclosed cavities, are also relaxed to enable the manufacturability evaluation of “gray” geometries that occur during the density-based topology optimization. Examples on minimum compliance structural assembly design for sheet metal stamping (MTO-S), die casting (MTO-D), additive manufacturing (MTO-A), and continuous fiber printing process (MTO-C) show promising advantages over the conventional monolithic topology optimization.  In particular, manufacturing constraints previously applied to monolithic topology optimization gain new interpretations when applied to multi-component assemblies, which can unlock richer design space for topology exploration.  The talk will conclude with a brief overview of the latest developments towards the MTO framework for foldable “4D” printed structures.

Biographical Sketch: Kazuhiro Saitou is a Professor of Mechanical Engineering at the University of Michigan, Ann Arbor, Michigan, USA. He currently serves for the Department as an Associate Chair for Graduate Education. He received BEng degree from University of Tokyo, Japan, and MS and PhD degrees from the Massachusetts Institute of Technology (MIT), USA. His research interest includes algorithmic and computational design synthesis and design for manufacture and assembly, with applications in mechanical, industrial, and biomedical systems.  He is a Fellow of ASME and IEEE.

http://s.uconn.edu/meseminar11/19/21

Password: 1234

Abstract: I will provide an account of the interesting dynamics exhibited by droplets at multiple length and time scales in completely different domains, namely gas turbines and COVID-19. In the first part of my talk, I will provide some insights into the dynamics of spray-swirl interaction with particular focus on droplet transport, breakup and dispersion. I will show how the fundamental insights gained through such interactions can be used to design a new class of atomizers in gas turbines. In the second part of my talk, I will discuss how the spread of COVID can happen through respiratory droplets and fomites. In this part, I will provide a detailed exposition of how respiratory droplet dynamics can be combined with a pandemic model to provide a first principle insights into infection spread rates. We will show through experiments using surrogate fluids how such models can be experimentally verified rigorously. Subsequently, I will show how fomites form and how the virions are embedded in the crystal network using both contact free as well as sessile droplets.

 

Biographical Sketch: Prof. Saptarshi Basu is currently DRDO Chair Professor in the department of mechanical engineering at IISc. Prof. Basu primarily works on multiphase systems, especially droplets at multiple length and timescales across multiple application domains. He is a fellow of Indian National Academy of Engineering, ASME, Institute of Physics, Royal Aeronautical Society and Royal Society of Chemistry. Prof. Basu is the recipient of DST Swarnajayanti Fellowship in engineering.