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This research uses virtual reality (VR) to immerse human subjects in an active school shooting scenario in order to generate ecologically valid models of school shooter movement and behavior. Historically, data recovered from U.S. school shootings has lacked the fidelity needed to model shooter movement; consequently, simulations of school shootings have had to rely on significant and unsupported assumptions about the movements of the shooter and/or victims. We asked human subjects to act as school shooters in a virtual reality simulation. We then recorded their movements, observations, and actions. Our results show that participant shooters are statistically equivalent to historical incidents with respect to aggregate engagement metrics (shot rate, victim rate, and accuracy) across most scenarios. Moreover, empirical models trained on participant data reduced prediction error by at least 15.5% compared to heuristic baselines and 16.7% compared to models trained on pedestrian data. Overall, this work provides a reproducible framework for data-driven modeling of shooter movement, supporting controlled simulation-based evaluation of response strategies. 

Coastal embayments in nearshore upwelling systems (“upwelling bays”) play a disproportionately large role in regional oceanography. In these systems, local diurnal wind forcing and thermal gradients associated with an upwelling shadow front that forms between warmer sheltered waters inside the bay and colder recently upwelled waters outside the bay strongly influence local temperature dynamics. Despite their importance to local ecosystems, there are no long-term studies that assess the heat budget inside upwelling bays. In this study, we analyzed approximately two years of water temperature throughout the water column using an autonomous profiler in a small upwelling bay in central California (San Luis Obispo Bay). We coupled these measurements with local meteorological data and in-situ temperature measurements made outside the bay to investigate how local diurnal wind forcing and the presence of the upwelling shadow front modify the diurnal heat budget inside the bay. Over the study period, strong seasonality in regional upwelling coincided with changes in local wind forcing, front strength (bulk temperature difference between inside and outside the bay), and temperature structure, from which we identified various forcing regimes to quantify the diurnal heat budget. During the non-upwelling season when the front was largely absent, the heat budget was primarily a balance between changes in heat content and surface heat fluxes, regardless of local wind forcing strength. This was also the primary balance during the upwelling season when local winds were weak. In contrast, during the upwelling season when the upwelling shadow front was persistent and the local winds were strong, increasing front strength led to increasingly large residual heat fluxes, which were interpreted to be due to advection (advective fluxes not calculated directly). These results highlight the importance of both local wind forcing and frontal intensity on the heat budget inside the upwelling bay, with significant implications for residence time, temperature dynamics, and local biogeochemistry in similar systems that are ubiquitous globally. 

Steady-state and time-resolved fluorescence was used to investigate the solvation and rotational dynamics of coumarin 153 (C153) and coumarin 343 (C343) in binary solutions of methanol and glyceline, a deep eutectic solvent (DES) composed of a 1:2 molar ratio of choline chloride and glycerol. Time-resolved Stokes shifts were used to quantify the solvation dynamics and were found to be biexponential for both C153 and C343 with nearly identical integral solvation times. The solvation times were also found to be weakly dependent upon solution viscosity, and a power law exponent of p = 0.18 was found for mole fractions of glyceline greater than xDES = 0.2. Solute rotational dynamics were explored using time-resolved fluorescence anisotropy. The reorientation times of C153 and C343 were found to be single exponential at all mixture compositions but did not follow a power-law dependence on solution viscosity. Instead, there was evidence for preferential solvation of the probes by components of glyceline.