This paper considers the issue of safety in Automated Vehicle Highway Systems (AVHS). An approach is proposed for proving that a system is safe. The design for a proposed AVHS is considered and shown that if the physical controllers in the vehicles satisfy a set of constraints then the AVHS is safe. The authors contend that the problem of checking whether the controllers satisfy the constraints is equivalent to solving an optimal control problem.

Compartmentalized G protein-coupled receptor (GPCR) signaling has been increasingly proven to play a large role in regulating distinct cellular responses. The idea that GPCRs could signal from endosomes was already a relatively novel concept a mere two decades ago. However, early evidence showed that internalization of some GPCRs led to sustained activity rather than an abolishment of signaling. Still, this secondary phase of GPCR signaling was implicated in activation sourced from the cell surface. The concept of distinct signaling hubs originating from other membrane-bound organelles was truly novel. The discovery that the beta 1 adrenergic receptor, an important GPCR in regulating heart contractility and relaxation responses, could signal from the Golgi apparatus begged the question of whether other similar GPCRs could signal from subcellular organelles. Here, I uncover that D1 dopamine receptor (D1DR) can signal from multiple signaling hubs, identify the mechanism in which dopamine accesses intracellular membrane compartments, and speculate on the potential implications of this novel work. First, I use a biosensor tool to visualize compartmentalized D1DR signaling using live-cell confocal fluorescence microscopy. I identified that organic cation transporter 2 (OCT2), a low-affinity high-capacity transporter of several neurotransmitters such as dopamine, facilitated dopamine transport intracellularly to access the Golgi pool of receptor. I also observed compartmentalized dopaminergic signaling in physiologically relevant cell types, including in key dopaminergic neurons and in kidney cells. Finally, I show that GPCR signals originating from distinct subcellular signaling hubs leads to distinct modulations of the downstream signaling cascades, indicating that receptor signaling from the Golgi could be regulating transcriptional responses. Put together, this work identifies a novel pathway of dopaminergic signaling and suggests that discrete signaling hubs within the cell distinctly regulate vital cellular responses.

This dissertation focuses on observing and controlling cold atom-ion collisions. Such collisions have numerous applications ranging from providing insight into the formation of the interstellar medium to presenting a potential platform for developing quantum information architectures. The experimental apparatus at the center of this work is a hybrid atom-ion trapping system in which laser-cooled Ca atoms held within a magneto-optical trap are spatially overlapped with ions localized within an ion trap. The ions studied in this work are both laser-cooled atomic ions as well as sympathetically cooled molecular ions. As detailed in the remainder of this thesis, by employing tools such as optical pumping, collision energy control, and mass spectrometry, reactions between these species can not only be studied with high precision but can also be controlled, leading to expanded tools for reaction engineering as well as the creation of exotic chemical species. Finally, this work also includes efforts to use inelastic collisions between room temperature BaCl^+} molecular ions and cold Ca atoms to create ro-vibrational ground state molecules, a precursor for developing a high-fidelity qubit based on rotational levels in polar molecules.

In this study, we demonstrate the use of Stokes polarimetry in combination with polarized light microscopy as a powerful tool in the characterization of anisotropic polymeric materials including collagen and poly (ϵ-caprolactone) fibers. Structural anisotropy has been shown to translate to optical anisotropy in the form of birefringence. We demonstrate that polarized light microscopy and Stokes polarimetry can be used to enhance the visualization of fibrous structures that are not ordinarily accessible by conventional microscopy techniques, by leveraging the birefringence of the material. With polarized light microscopy, we show the existence of birefringent Maltese cross structures in collagen synthesized at 22 0C and perform structural analysis of the system using Stokes polarimetry. The highly fibrous microstructural arrangements observed by polarized light microscopy and Stokes polarimetry for collagen synthesized at 40 0C and poly (ϵ-caprolactone) fibers can provide insights into the kinetics of polymerization. We also observe a change in birefringence due to the effect of strain on super elastic poly (ϵ-caprolactone) fibers. Overall, we demonstrate that combining Stokes polarimetry and polarized light microscopy has the potential to provide quantitative, point by point structural analysis of fibrous biomaterials. This study holds potential to provide insights into the kinetics and mechanics of disease progression and polymer synthesis.