This award supports theoretical, computational, and data-driven research, and education to study how living systems self-regulate by investigating mechanical networks that are tunable through their links at edges. The central goal is to uncover an organizing principle which can be further applied to materials design. On the face of it, the mechanism by which many enzymes are turned on and off (allostery), the ability of the brain vascular system to adjust blood flow to different parts of the brain on demand, the ability of the cellular cytoskeleton to control robustly cell shape and mechanics even as they are changing, and morphological processes in embryonic development have little in common. This project suggests and explores the possibility that there is an underlying organizing principle that unifies these phenomena. In each of these systems, the network connectivity can be modified at the level of individual links in the network, by evolution, by dilating or contracting blood vessels, by specific proteins or by adjustable levels of protein expression, respectively. This enables each link to have different and mutable properties that can be tuned in order to give rise to the aforementioned phenomena. The lessons that the PI and her research team will learn by studying this new possible organizing principle and its consequences will be applicable to synthetic systems and materials, and may provide insight into how to design materials capable of performing tasks that approach the diversity and complexity of those routinely accomplished by living systems.
The PI will continue vigorous outreach, advocacy, mentoring and service, particularly for women; a few of her recent activities include (1) Lecturer to Philadelphia area high school science teachers; (2) Panelist for discussions for women in academic science; (3) Speaker and co-host of panels addressing issues affecting Asian-American scientists and engineers; (4) Deliverer of public lectures in Philadelphia and elsewhere; (5) Holder of leadership positions in the American Physical Society, representing approximately 55,000 physicists in the US and worldwide, as well as the Physics Section of the American Association for the Advancement of Science. The PI also meets with groups of women students, postdocs and faculty during seminar/colloquium trips to academic institutions in fields ranging from physics and chemistry to materials science and mechanical engineering.
This award supports theoretical, computational, and data-driven research, and education to study athermal mechanical networks with tunable edge properties to reveal organizing principles that unite different features of living matter systems and are applicable to materials design. Living matter systems are often composed of constituents that are non-identical (such as amino acids in a protein or cells in a tissue) and mutable (amino acid sequences can change during evolution and cells differentiate during development). The ability of scientists to connect microscopic properties to collective behavior in many-body systems, in which every constituent can be different and can alter its properties, is currently limited. This project is focused on a class of such systems, athermal mechanical networks with tunable edge properties. The PI and collaborators have previously shown that such networks are highly malleable in their properties upon alteration of a very small fraction of edges.
This project pursues three main directions of research on tunable mechanical networks. (1) Topological data analysis and machine learning methods will be used to connect microscopic properties to collective behavior. (2) Potentially abstract questions involving adaptability, evolvability and robustness of these systems will be addressed in a concrete, quantitative way. (3) Edge tuning will be explored as a new organizing principle for understanding and potentially designing functions and processes in mechanical networks ranging from molecular to cellular and tissue scales in living matter.
The proposed research will use data mining methods to go beyond statistical mechanics to understand microscopic origins of many-body behavior. Such methods have been used in physics for fast approximation (e.g. in calculating electronic structure) or classification (e.g. in developing triggers for high energy experiments or distinguishing astronomical objects in images), but there has been little focus on applying them towards the central goal of condensed matter theory. The research also brings a unifying viewpoint to biological processes ranging from the molecular to the cellular and tissue scales. It will also provide a new perspective to semiflexible networks, a focus of considerable excellent soft and living matter research, as well as epithelial tissues, systems of increasing interest in the soft/living matter community. The topological data analysis developed previously by the PI and collaborators will be generalized and applied to real proteins, potentially leading to new understanding of the link between conserved amino acid sequences and allostery. An eventual goal is to develop a new strategy for designing synthetic allosteric proteins, which would have potential medical and other applications. The concept of tuning as a new organizing principle in mechanical networks across scales in living systems could allow useful insights to be exchanged across the fields of physics, materials science, mechanical engineering, bioengineering, structural biology, cell biology and developmental biology, to mutual benefit.
The PI will continue vigorous outreach, advocacy, mentoring and service, particularly for women; a few of her recent activities include (1) Lecturer to Philadelphia area high school science teachers; (2) Panelist for discussions for women in academic science; (3) Speaker and co-host of panels addressing issues affecting Asian-American scientists and engineers; (4) Deliverer of public lectures in Philadelphia and elsewhere; (5) Holder of leadership positions in the American Physical Society, representing approximately 55,000 physicists in the US and worldwide, as well as the Physics Section of the American Association for the Advancement of Science. The PI also meets with groups of women students, postdocs and faculty during seminar/colloquium trips to academic institutions in fields ranging from physics and chemistry to materials science and mechanical engineering.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
