Grid cells in the entorhinal cortex are believed to establish their regular, spatially correlated firing patterns by path integration of the animal's motion. Mechanisms for path integration, e.g. in attractor network models, predict stochastic drift of grid responses, which is not observed experimentally. We demonstrate a biologically plausible mechanism of dynamic self-organization by which border cells, which fire at environmental boundaries, can correct such drift in grid cells. In our model, experience-dependent Hebbian plasticity during exploration allows border cells to learn connectivity to grid cells. Border cells in this learned network reset the phase of drifting grids. This error-correction mechanism is robust to environmental shape and complexity, including enclosures with interior barriers, and makes distinctive predictions for environmental deformation experiments. Our work demonstrates how diverse cell types in the entorhinal cortex could interact dynamically and adaptively to achieve robust path integration.

Science communication and outreach are essential for training the next generation of scientists and raising public awareness for science. Providing effective science, technology, engineering, and mathematics (STEM) educational outreach to students in classrooms is challenging because of the need to form partnerships with teachers, the time commitment required for the presenting scientist, and the limited class time allotted for presentations. In our Present Your Ph.D. Thesis to a 12-Year Old outreach project, our novel solution to this problem is hosting a youth science workshop (YSW) on our university campus. The YSW is an interpersonal science communication and outreach experience in which graduate students from diverse scientific disciplines introduce middle and high school students to their cutting-edge research and mentor them to develop a white-board presentation to communicate the research to the workshop audience. Our assessment of the YSW indicated that participating young students expressed significantly more positive attitudes toward science and increased motivation to work in a STEM career after attending the workshop. Qualitative follow-up interviews with participating graduate students' show that even with minimal time commitment, an impactful science communication training experience can be achieved. The YSW is a low-cost, high-reward educational outreach event amenable to all disciplines of science. It enhances interest and support of basic science research while providing opportunities for graduate students to engage with the public, improve their science communication skills, and enhance public understanding of science. This YSW model can be easily implemented at other higher education institutions to globally enhance science outreach initiatives.

Phenomenological studies of Flavored Dark Matter (FDM) models often have to assume a near-diagonal flavor structure in the coupling matrix in order to remain consistent with bounds from flavor violating processes. In this paper we show that for Lepton FDM, such a structure can naturally arise from an extra dimensional setup. The extra dimension is taken to be flat, with the dark matter and mediator fields confined to a brane on one end of the extra dimension, and the Higgs field to a brane on the other end. The Standard Model fermion and gauge fields are the zero modes of corresponding bulk fields with appropriate boundary conditions. Global flavor symmetries exist in the bulk and on the FDM brane, while they are broken on the Higgs brane. Flavor violating processes arise due to the misalignment of bases for which the interactions on the two branes are diagonalized, and their size can be controlled by a choice of the lepton profiles along the extra dimension. By studying the parameter space for the model, we show that when relic abundance and indirect detection constraints are satisfied, the rates for flavor violating processes such as µ → eγ remain far below the experimental limits.

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