Sexual minorities consistently report more alcohol use than heterosexual individuals, and sexual minority women tend to report more alcohol use than sexual minority men (Amadio, 2006; Kerr et al., 2015; Rosario et al., 2014). Some evidence suggests that this disparity in comparison to heterosexuals may be problematic drinking, such as binge drinking and alcohol dependence, rather than just higher consumption of alcohol. Thus, it is important to examine which variables are related to problematic drinking among sexual minority women. One factor that may explain problematic drinking for sexual minority women is proximal minority stress, such as anticipated stigma (expectations of unfair treatment) and internalized stigma (negative attitudes toward the self about one’s sexual orientation) (Meyer, 2003). Previous research has found that internalized stigma predicts more problematic drinking (Feinstein & Newcomb, 2016; Lea et al., 2014). Additionally, proximal minority stress may be indirectly related to problematic drinking through variables like depression, social support, and drinking motives (Lehavot & Simoni, 2011; Lewis et al., 2016). However, findings on anticipated stigma have inconsistently shown a relationship with problematic drinking (Hatzenbuehler et al., 2008; Reisner et al., 2015). The current study tested a path analysis model examining how proximal minority stress may be related to problematic drinking among sexual minority women. Participants included 101 women who identified as lesbian, bisexual, and other non-heterosexual orientations. Participants were mainly white, and came from all regions of the United States (Northeast, South, Midwest, West). They completed the following measures: the Internalized Stigma Subscale of the Perceived Stigma Scale (Mickelson, 2001), the Discrimination Scale (adapted from Williams, 1997), the Multidimensional Scale of Perceived Social Support (Zimet et al., 1988), the Center for Epidemiological Studies Depression Scale (Radloff, 1977), the Drinking Motives Questionnaire (Cooper, 1994), and the AUDIT (Saunders et al., 1993). The final model tested anticipated stigma and internalized stigma as predictors of social support and depression; depression significantly predicted coping and enhancement motives, which in turn predicted problematic drinking. Age, living in the Northeast, and being a racial/ethnic minority were covariates of depression, internalized stigma and social support respectively. A path analysis conducted via EQS determined that the model had good fit (Chi-square/df = 1.10, p = 0.32, CFI = .988, SRMR = 0.082, RMSEA = .032 (90% CI [0.001, 0.082]). These results support the hypotheses that minority stress is related to more problematic drinking through depression and substance use motives. Findings could suggest that future research and interventions should examine the replacement of negative coping mechanisms, like drinking, with more positive coping mechanisms among sexual minority women.

Invasive plants are widely cited as a major threat to native plant communities, and the correlation between plant invasions and a subsequent decline in native species is well documented at some scales. However, one outstanding question is the degree to which invasive species are a driver of native plant declines versus a correlate of other drivers, such as habitat disturbance. These two hypotheses to explain the dominance of invasive species in communities have been termed the ‘driver’ and ‘passenger’ models, respectively. In order to understand the impacts of plant invasion on native plants we need more studies that consider the role of correlated environmental predictors, which may play unseen roles in the response and recovery of native plant communities frequently attributed to invasion alone. Using a large database of plant community and environmental data from sites across Southern Ontario, I used path analyses to examine the direct and indirect relationships between disturbance, exotic and native plant richness, and relative abundance. Counter to my initial predictions, I found support for both the partial passenger and partial driver models of invasive dominance, while full passenger models were outright rejected. The causal hypotheses consistent with the data indicated significant relationships between native and exotic species richness and native and exotic relative abundance across models. An exploratory analysis, which examined species-specific models, found that the data was consistent with seven out of twelve causal hypotheses. Models that could not be rejected were split almost evenly across full passenger, partial passenger, and partial driver models. Model support varied according to the species included in the dataset suggesting that the best fit underlying model of invasive dominance likely varies by species. While the partial passenger and partial driver models were recurrently consistent with the data, no single model described the underlying patterns of invasive dominance across all systems.

The Himalayan orogen provides a natural laboratory to test models of orogenic development due to large-scale continental collision. The Greater Himalayan Series (GHS), a lithotectonic unit continuous along the entire length of the belt, comprises the metamorphic core of the Himalayan orogen and underlies the highest topography. GHS rocks are exposed as a moderately north-dipping slab bounded below by the Main Central Thrust (MCT) and above by the South Tibetan Detachment System (STDS) of normal faults. Coeval reverse- and normal-sense motion on the crustal-scale MCT and STDS ductile shear zones allows the GHS to be modeled as an extruded wedge or channel of mid-crustal material. Due to this unique tectonic setting, the deformation path of rocks within the bounding shear zones and throughout the core of the GHS profoundly influences the efficiency of extrusion and exhumation processes. Attempts to quantify GHS deformation and metamorphic evolution have provided significant insight into Himalayan orogenic development, but these structural and petrologic studies are often conducted in isolation. Penetrative deformation fabrics developed under mid-upper amphibolite facies conditions within the GHS argue that deformation and metamorphism were coupled, and this should be considered in studies aimed at quantifying GHS teconometamorphic evolution. This work focuses on two projects related to the coupled deformation, thermal and metamorphic evolution during extrusion and exhumation of the GHS, focused on the lower and upper margins of the slab. A detailed examination of the P--T history of a schist collected from within the MCT zone of the Sutlej River, NW India, provides insight into the path experienced by these rocks as they traveled through the crust in response to the extreme shortening related to India-Asia collision. Combined forward thermodynamic and diffusion modeling indicates compositional zoning preserved in garnet has remained unmodified since growth and can be related directly to the P--T--X evolution of rocks from this zone. Classic porphyroblast--matrix relationships coupled with the above models provide a structural framework within which to interpret the microstructures and provide additional constraints on the relative timing of metamorphic and deformation events. A combined microstructural and quartz petrofabric study of rocks from the highest structural levels of the GHS in the Zanskar region was completed. This work provides the first quantitative estimate of temperatures attending normal-sense shearing along the Zanskar Shear Zone, the westernmost strand of the STDS. Results indicate penetrative top-N (extensional) deformation occurred at elevated temperatures and resulted in the telescoping of isothermal surfaces present during shearing and extrusion of GHS rocks. Simple geometric models invoking heterogeneous simple shear parallel to the overlying detachment require dip-slip displacement magnitudes on the order of 15--40 km, identical to estimates derived from nearby barometric analyses. Finally, focus is given to the rotational behavior of rigid inclusions suspended in a flowing viscous matrix from a theoretical perspective. Predictions of clast rotational behavior have been used to construct several kinematic vorticity estimation techniques that have become widely adopted for quantitative studies of naturally deformed rocks. Despite the popularity of the techniques, however, basic questions regarding clast-based analyses remain open. Therefore a numerical model was constructed and a systematic investigation of 2- and 3D clasts suspended in steady and non-steady plane-strain flows was undertaken to determine likely sources of error and the intrinsic strengths and limitations of the techniques. / Ph. D.

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For robots to move out of the lab and into the real-world, they must be able to plan routes not only through space but through time as well. The introduction of a time factor to the planning process implies that robots must reason about other processes and agents that move through space independently of the robot's actions. This thesis presents an integrated route planner and spatial representation system for planning real-time paths through dynamic domains called Robonav. Robonav will find the safest 9 most efficient route through time and space as described by an evaluation function. Due to the design of the spatial representation and the mechanics of the algorithm, Robonav has an isomorphic mapping onto a machine with a highly parallel SIMD architecture. When Robonav is operated in a predictable domain, paths are found in O(p) time (where p is the length of a path). In unpredictable domains, where Robonav is operated in incremental mode, paths are found and executed in O(p²) time. / Master of Science

Least Cost Path Analysis (LCPA) is a GIS-based approach for calculating the most efficient route between a start and end point, often in terms of shortest time or least amount of energy. The approach is often applied in archaeology to estimate locations of sites, and routes between them. We applied LCPA to estimate how sites in the Andes in the eastern portion of the Inka empire may have connected to sites in the western Amazon Basin. Our approach further used the known Inka Road network to test performance of two types of LCP models (linear vs. areal calculation) and four types of cost functions. LCPs can be calculated with an areal approach, where each cell of the DEM is given one overall slope value, or linearly, where the direction of travel across a cell affects the slope value. Four different algorithms were tested: Tobler's Hiking Function (1993), Tobler's Hiking Function with a vertical exaggeration of 2.3 based on human perceptions of slope (Pingel 2010), Pingel's empirical estimation approach (2010), and Pandolf et al.'s energy expenditure equation (1977) using both an areal and linear approach for all the algorithms. An initial study was conducted in the Cusco region and results were compared to the Inka Road network using the linear accuracy assessment method of Goodchild and Hunter (1997) and Güimil-Fariña and Parcero-Oubiña (2015). The findings suggest that the empirical estimation and caloric cost methods were the most accurate and performed similarly, both were more accurate than travel-time based costs, and linear methods were better than areal based methods when using higher resolution DEM inputs. / Master of Science / Least Cost Path Analysis (LCPA) is a method used for determining the most efficient route between a start and end point, often in terms of shortest time or least amount of energy. The approach is often applied in archaeology to estimate locations of sites, and routes between them. We applied LCPA to estimate how sites in the Andes in the eastern portion of the Inka empire may have connected to sites in the western Amazon Basin. Our approach further used the known Inka Road network to test performance of two types of Least Cost Path (LCP) models (linear vs. areal calculation) and four types of cost functions. LCPs can be calculated with an areal approach, where each cell in an elevation dataset is given one overall slope value, or linearly, where the direction of travel across a cell affects the slope value. Four different ways of calculating cost were tested: Tobler's Hiking Function (1993) using time as a cost, Tobler's Hiking Function with a vertical exaggeration of 2.3 where the cost is based on human perceptions of slope (Pingel 2010), Pingel's empirical estimation approach (2010) based on the preexisting Inka Road system, and Pandolf et al.'s energy expenditure equation (1977). All four ways of calculating costs were used both an areal and linear approach. An initial study was conducted in the Cusco region and results were compared to the Inka Road network by seeing what percent of each LCP was within 500 m of the Inka Road. The findings suggest that the empirical estimation and energy based methods were the most accurate and performed similarly, both were more accurate than travel-time based costs, and linear methods were better than areal based methods when using higher resolution elevation data inputs.

The construction of dams and hydro-power stations are some of the most common anthropogenic changes of watercourses and rivers. While being important to humans and society by providing electricity, these obstructions of watercourses can have severe consequences for the aquatic ecosystems. One consequence is that dams often hinder the important movement of migrating fish species between habitats. This can lead to decline and even extinction of important fish populations. To prevent these negative effects, a number of different fish passage systems, including nature-like fishways, have been developed. Nature-like fishways mimic natural streams in order to function as a natural corridor for a wide range of species. Planning and construction of a nature-like fishway is a complex task that often involves many different interests. In the present study a combination of multi-criteria decision analysis and least-cost path analysis is used for determining the best location for a nature-like fishway past Strömdalen dam in Gavleån, Sweden. An anisotropic least-cost path algorithm is applied on a friction-layer and a digital elevation model, and the least-cost path for a nature-like fishway is determined. The results show that the method is useful in areas of varying topography and steep slopes. However, because low slope is a very important factor when constructing a nature-like fishway, slope becomes the dominating factor in this analysis at the expense of e.g. distance to roads. Combining the methods with results from biological studies of fish behavior and detailed hydrological modelling would provide a very strong tool for the planning of nature-like fishways.

The aim of this study was to examine the impact of role stress (ambiguity and conflict) on job satisfaction through psychological empowerment in the workplace. Data was collected from 314 workers from southern Portugal (M = 35.39, SD =10.66; 69.75% women) age age Results indicated that role conflict had a direct effect on job satisfaction, while the impact of role ambiguity on job satisfaction was totally mediated by meaning and self-determination. Psychosocial interventions in companies should focus on prevention of role stress and pro­ motion of psychological empowerment in the workplace. / El objetivo de este estudio fue analizar el impacto del estrés de rol (ambigüedad y conflicto) sobre la satisfacción laboral a través del empowerment psicológico en el trabajo. Se obtuvieron datos de una muestra de 314 trabajadores del sur de Portugal (M = 35.59, DE = 10.66). edad edad El 69.75% de los participantes fueron mujeres. Los resultados mostraron que el efecto del conflicto de rol fue directo sobre la satisfacción laboral, mientras que el efecto de la ambi­ güedad fue mediado por las dimensiones autodeterminación y significado del empowerment psicológico. Las intervenciones en las empresas deben centrarse en la prevención del estrés de rol y en el aumento del empowerment psicológico. / O objetivo deste estudo é analisar o impacte do stresse de papel (ambiguidade e conflito) sobre a satisfação no trabalho através do empowerment psicológico no trabalho. Os dados foram obtidos através de uma amostra de 314 profissionais ativos do sul de Portugal (M = idade 35.59, DP = 10.66). 69.75% dos participantes eram mulheres. Os resultados mostraram idade que o efeito do conflito de papel sobre a satisfação no trabalho é direto, enquanto que o efeito da ambiguidade sobre a satisfação no trabalho é mediado pelas dimensões autodeter­ minação e significado do empowerment psicológico. As intervenções nas empresas devem centrar-se na prevenção do stresse de papel e no aumento do empowerment psicológico.