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Public transit systems are crucial to mobility and access in cities throughout the world. This article addresses the importance of these transit systems in San Antonio, Texas. We show how transit systems exacerbate race and class inequality and the accessibility of city spaces with a focus on San Antonio’s buses. Using mixed methods (surveys, interviews, ethnography, and document analysis) we illustrate that poor and working-class Latinx communities experience reduced access to resource rich areas of the city when they are dependent upon the city’s public transportation. To better describe this experience we use the concepts, enclaves of exclusion and enclaves of inaccessibility. Our findings show that mobility through San Antonio for poor and working class Latinxs is limited especially for people in these communities who rely on public transit. This experience with these public transit systems often renders them as individuals who do not belong in certain neighborhoods, and ultimately reinforces the longstanding histories of race and class segregation in San Antonio. 

Tourism offers many economic benefits but can have long-lasting ecological effects when improperly managed. Tourism can cause overwhelming pressure on wastewater treatment systems, as in Belize, where some of the over 400 small islands (cayes) that were once temporary sites for fishermen have become popular tourist destinations. An overabundance of nitrogen, in part as a result of incomplete wastewater treatment, threatens human health and ecosystem services. The tourism industry is a complex and dynamic industry with many sectors and stakeholders with conflicting goals. In this study, a systems thinking approach was adopted to study the dynamic interactions between stakeholders and the environment at Laughing Bird Caye National Park in Belize. The project centered on nutrient discharges from the caye’s onsite wastewater treatment system. An archetype analysis approach was applied to frame potential solutions to nutrient pollution and understand potential behaviors over time. “Out of control” and “Underachievement” were identified as system archetypes; “Shifting the Burden” and ‘‘Limits to Success’’ were used to model specific cases. Based on these results, upgrading of the wastewater treatment system should be performed concurrently with investments in the user experience of the toilets, education on the vulnerability of the treatment system and ecosystem, and controls on the number of daily tourists. 

Shared-gaze visualizations (SGV) allow collocated collaborators to understand each other's attention and intentions while working jointly in an augmented reality setting. However, prior work has overlooked user control and privacy over how gaze information can be shared between collaborators. In this work, we examine two methods for visualizing shared-gaze between collaborators: gaze-hover and gaze-trigger. We compare the methods with existing solutions through a paired-user evaluation study in which participants participate in a virtual assembly task. Finally, we contribute an understanding of user perceptions, preferences, and design implications of shared-gaze visualizations in augmented reality. 

In 2019, interdisciplinary teams of anthropology and environmental engineering PhD students went to Placencia Village, Belize to study stakeholder-driven issues related to coastal resilience. Our team explored wastewater management on a few of the more than 400 small cayes peppering the Belize Barrier Reef. These islands have transitioned from temporary sites for overnight fishers to crowded tourism destinations. Wastewater management has struggled to keep pace with these changes, spurring concerns about the health of the reef. Our task was to construct contextualized system dynamic models which would be useful to those concerned. Along the way however, we ran into tensions related to the underlying logic, and representations of people, in mathematical descriptions of social and technical configurations. This article lays out the context and lessons learned from our encounter with interdisciplinary systems modeling. 

In this work, we demonstrate a four-core multicore fiber photonic lantern tip/tilt wavefront sensor. To diagnose the low-order Zernike aberrations, we exploit the ability of the photonic lantern to encode the characteristics of a complex incoming beam at the multimode facet of the sensor to intensity distributions at the multicore fiber output. Here, we provide a comprehensive numerical analysis capable of predicting the performance of fabricated devices and experimentally demonstrate the concept. Two receiver architectures are implemented to discern tip/tilt information by (i) imaging the four-core fiber facet on a 2D detector and (ii) direct power measurement of the single mode outputs using a multicore fiber multiplexer and photodetectors. For both receiver schemes, an angular detection window of $\sim <\#comment/>{0.4}^{\circ <\#comment/>}$at 1064 nm can be achieved. Our results are expected to further facilitate the development of intensity-based fiber wavefront sensors for adaptive optics systems.