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THE INFLUENCE OF BILINGUALISM ON MOTOR RECOVERY AFTER STROKE
No full textObjective: Bilingualism has been associated with enhanced executive function and cognitive reserve. In this literature review, we aimed to analyze the influence of bilingualism on motor recovery after stroke. Methods: A literature-based review was conducted using databases such as PubMed and Google Scholar. Sources were filtered to prioritize studies comparing neurophysiological characteristics and stroke recovery outcomes in bilingual versus monolingual individuals, with a specific focus on motor recovery. Results: The findings indicate that bilingual individuals possess greater gray matter density in regions like the anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (dlPFC), along with increased white matter volume in interhemispheric communication tracts like the corpus callosum. These adaptations are linked to enhanced executive function, attention, and cognitive flexibility, which support effective motor rehabilitation. Conclusions: Although direct studies on the impact of bilingualism on post-stroke motor outcomes remain limited, existing research on the neuroplasticity and the cognitive advantages of bilingualism supports the hypothesis that the cognitive advantages of bilingualism can support effective rehabilitation
PCR PRIMER EFFICACY IN DETERMINING SALMONELLA PREVALENCE IN SOUTHERN ARIZONA SHELTER DOGS AND FERAL CATS
No full textSalmonella is an enteric pathogen that can be transmitted zoonotically between humans and animals, including companion cats and dogs. One of the virulence factors that enables colonization of the gastrointestinal tract is the type III secretion system, as encoded in Salmonella Pathogenicity Island 1 (SP-1), and one of the component proteins of this virulence factor is the Invasive A protein (InvA). InvA is encoded by the invA gene, which is highly conserved within Salmonella species, so amplification of this gene through polymerase chain reaction (PCR) is often used to detect clinical isolates of Salmonella in humans, animals, and contaminated food and water sources. This study utilized the invA PCR to determine the prevalence of Salmonella in shelter dogs and feral cats. Additionally, PCR detection efficacy was studied by utilizing different primer sets and the additive bovine serum albumin (BSA). Three different primer sets, coined the "MC" primer set, "KC" primer set, and "VO" primer set, were tested. The MC primer set detected the invA gene in 16 of 58 canine fecal samples and 6 of 56 feline fecal samples, the KC primer did not detect the invA gene in any canine fecal sample, and the VO primer set detected the invA gene in 7 of 58 canine fecal samples. It was discovered that the MC primer set was able to detect the invA gene at a lower DNA concentration than the other two, which could contribute to the higher frequency of positive results obtained with that primer set. The effects of BSA addition were observed in sample groupings from shelter dogs and feral cats that were initially positive or negative for the invA gene in their first PCR, where the presence of BSA influenced PCR results from the original samples. The addition of BSA caused 1 sample from both the canine and feline fecal samples that had initially returned as negative to be positive for the invA gene; however, 1 sample from both the canine and feline fecal samples that had initially returned as positive was not positive in the PCR with BSA. PCR is a sensitive and specific tool to confirm the presence of invA, as indicative of Salmonella, and appropriate adjustments, regarding the primer set characteristics and reaction mixture additives, should be considered. Optimizing the PCR conditions will maximize the reliability of PCR as a diagnostic tool to confirm Salmonella diagnoses and to guide treatment and preventative strategies
THE ROLE OF OCCUPATIONAL THERAPY IN ENHANCING INCLUSIVE CLASSROOM PRACTICES
No full textThis study employed a qualitative case study approach to explore the professional practices and experiences of one occupational therapist and general education preschool teacher in a real-world setting. In this study, the researcher aimed to reflect on previous literature and combine observation and interview data on the practitioners' instructional methods, decision-making processes, and lived experiences in relation to inclusion. The goal was to gain a nuanced understanding of how an occupational therapist and general education preschool teacher operate in their professional environment, both from their perspectives and through direct observation
Are We in the Picture? To What Extent, If at All? Mexican and Latin American International Student Representation on Global Websites of Borderland Hispanic-Serving Institutions
No full textThis study is about how Higher Education Institutions that happen to be Hispanic Serving Institutions (HSI) that are located on border states show or portray international students from México and Latin America on their websites or not. International students can be the “ideal” student because they bring prestige and revenue to the institution. However, some international students can suffer stratification or invisibility due to their nationality or race. I inquiry how visible or not are Mexican students and Latinos on Hispanic Serving Institutions and how service is being implemented by answering these research questions. 1.-Do Borderlands HSI features Mexican and Latin American students in international websites, and to what extent if at all? And 2.- In which ways do international students from Mexico and Latin America forgoing these websites? Is this reflective of neo-racist? By using a comparative qualitative analysis on public discourse, I will study universities that happen to be on border states such as Arizona and Texas. This sample is composed of five universities, two of them in Arizona and three in Texas. Such as University of Arizona (UArizona), Arizona State University (ASU), University of Houston, Texas A & M, and University of Texas, at El Paso (UTEP). Research on HSI as well as on international students but is limited to the intersection of servingess or how servings applied if to international students
Geophysical Evolution of Sputnik Basin on Pluto
No full textThe past and present subsurface structure of icy outer Solar System worlds, such as Pluto, provides insight into their formation and interior evolution. Placing constraints on the structure of planetary interiors has been one of the primary challenges in the field of Solar System science. NASA’s New Horizons mission flyby of Pluto in 2015 revealed its surface in high resolution for the first time but did not gather any spatially resolved gravitational data. Consequently, Pluto’s interior is still mostly unknown. Sputnik basin, an ~2000 × 1000 km elongated impact basin in Pluto’s equatorial region observed on the encounter hemisphere, has played an integral role in shedding light on Pluto’s interior. In this thesis, I present new interpretations of Sputnik basin’s structure and support, proposing an evolutionary pathway for the basin with implications for Pluto’s past and present interior structure.This dissertation analyzes Sputnik basin through a set of multi-faceted techniques, including structural characterization of the basin, geoid and thermal modeling, to present a seamless story of the basin’s evolution. My investigations in Chapter 2 revealed that Sputnik basin is consistent with peak-/multiring basins in the inner Solar System, implying a decrease in any subsurface uplift by ~ 40%. A proposed peak-ring structure redefines the impactor diameter, impact angle, and subsequent impact basin evolution. In Chapter 3, I use a novel approach assuming the low-viscosity deposit within the basin conforms to Pluto’s geoid and calculate the gravity field over the basin considering both giant impact and peak-ring structures. Sputnik basin is most likely uncompensated and a mass deficit today. Here, I first propose that Sputnik basin may have transitioned from a past mass excess or overcompensated state to a present-day mass deficit through refreezing of the uplifted subsurface ocean beneath the basin. In Chapter 4, I utilize thermal modeling to show that this process can result in transitioning the basin’s mass anomaly to a current mass deficit. Inclusion of insulating layers and properties does not affect our results despite their influence on the refreezing timescale of the Pluto’s ice shell. These findings contribute to our understanding of Sputnik basin’s geophysical evolution, demonstrating the importance of large impact basin studies on data-limited icy outer Solar System worlds like Pluto
Structure and Glass Transition Behavior of As-Rich As-Se Glasses: Modeling and Experiment
No full textChalcogenide glasses have been widely used in various technologies due to their wide IR transparency and good glass forming ability. Arsenic selenide glasses (AsxSe100-x), in particular, have been readily adopted for IR applications and widely studied to provide insights into fundamental structure-property relationships. Arsenic rich AsxSe100-x glasses (? > 40), however, are marked by the presence of unusual structural phenomena which influence the properties of these glasses and are not yet fully understood, including features such as molecular units (As4Se3) and a second calorimetric signal during the glass transition. Therefore, the structure of these glasses has been reexamined in As-rich compositions using Raman spectroscopy and atomic simulations in an effort to clarify the structure and elucidate the origin of the second calorimetric signal. High-resolution Raman spectra of the As-Se glass binary reveal a complex evolution of the structure with increasing As content. The evolution of the structure in Se-rich compositions is consistent with the chain-crossing model, as previously established in the literature. However, analysis of the As-rich spectra with multivariant curve resolution (MCR) techniques reveals mixed As-(Se3-x, Asx) units and As-(As3) units as well as molecular As4Se3 and As4 butterfly units. A model of the spectrum made by fitting Gaussian functions to the MCR components was then used for structural analysis. The population of As4Se3 units was derived, which shows a maximum at x = 60% and a decoupling from the population of As-rich units, consistent with a local minimum in . Ab initio molecular dynamics modelling of the structure of As60Se40 glass was also performed. Comparison of the structure derived from characterization of the model to reported
experimental measurements of the glass show generally good agreement. Analysis of the structural units found in the model support the existence of As4Se3 molecules in the glass while casting further doubt on the presence of As4Se4. Furthermore, the individual molecular As4 units previously attributed to the 203 cm-1 peak in the Raman spectrum are found to be absent, with As4 butterfly units incorporated into the glass network present instead. First-principles Raman spectrum calculations performed on the As4 butterfly units find that the Raman spectrum of these units vary significantly depending on the configuration. Using various chain configurations and modifying the relaxation of these chains through tension suggests a convergence of the asymmetric stretching mode of these units toward the spectral feature near 203 cm-1 found in the glass, supporting the assignment of this feature to As4 butterfly units. Finally, the dynamics of the glass transition for As-rich As-Se glasses were characterized through modulated differential scanning calorimetry (MDSC) and reveal a bimodal glass transition exhibiting different relaxation behaviors for the two observed components. The prominence of this bimodal signal is maximized at the As60Se40 composition, coinciding with the local minimum in and the maximum population of As4Se3 molecules. In situ Raman spectroscopy of the As60Se40
composition heated through the show that the first peak in MDSC measurements correlates with the relaxation of the amorphous backbone while the second peak is associated with the decomposition of As4 butterfly units. Features associated with As4Se3 molecules appear to alter at the onset of , indicative of decoupling of these units from the glass network in accordance with reported behavior of molecular glasses
Fabrication and Integration Strategies for Atomically Precise Graphene Nanoribbon Field-Effect Transistors
No full textBottom-up synthesized, atomically precise graphene nanoribbons (GNRs) provide a powerful platform for studying electronic behavior in low-dimensional quantum systems and advancing next-generation nanoelectronic technologies. With their well-defined atomic structure, tunable bandgap, and excellent charge transport properties, GNRs are strong candidates for future low-power, high-performance electronics. Yet, despite their theoretical promise, experimental device performance remains limited. Bridging this gap requires advances in both materials synthesis and device fabrication. In this Thesis, I present our efforts to address these challenges through the development of integration strategies for GNR field-effect transistors (GNRFETs). I will first introduce a double-resist lithography process forintegrating 7- and 9-atom-wide armchair GNRs into FETs with sub-30 nm channel lengths in a local back-gate geometry. Next, I will discuss how this process was adopted to study GNR-FETs in two publications. The first paper demonstrated the long-term stability of passivated GNR devices, while the second enabled GNR integration via a sustainable, wafer-scale, and etch-free transfer method. Finally, I will describe a metal electrode transfer technique designed to enable scalable fabrication without direct metal deposition on the ribbons, aiming to reduce structural damage and improve the contact–channel interface. I will conclude by outlining the broader implications of this work, remaining challenges, and future directions toward realizing GNR-based nanoelectronics
Daisies in the Desert: On Drivers of Extreme Chromosome Number Reduction in Plants
No full textChromosome number is a key feature of the eukaryotic genome, both in terms of its taxonomic value and its potential to affect evolutionary dynamics. Flowering plants exhibit broad variation in chromosome number, from n = 2 to n ~320, but most taxa have numbers around n = 9-12. These low numbers exist in spite of multiple rounds of polyploidy, or whole genome duplication (WGD) experienced by most angiosperm lineages. That is, rather than successive genome doubling resulting in high chromosome numbers, most lineages experience dramatic chromosome number reduction following WGD during the diploidization process. The consistency of this pattern suggests a selective advantage to chromosome number reduction, but the ultimate drivers are unclear. This dissertation aims to provide insight into drivers of chromosome number reduction in angiosperms. Specifically, I first test a recent hypothesis that descending dysploidy following WGD is driven by selection to maintain gene flow between isolated sub-populations of a neo-polyploid lineage. Under this hypothesis, high chromosome numbers exacerbate the fitness effects of reciprocal gene loss, a potential mechanism by which reproductive isolation arises between lineages following WGD. I test this hypothesis using crossability data from congeneric pairs or groups of taxa, as well as chromosome numbers and estimates of shared WGD age in a comparative phylogenetic framework. My results provide no support for this hypothesis, as crossability showed no relationship with chromosome number or WGD age. I then examine patterns and drivers of chromosome number evolution in a group known for its low chromosome numbers, the Asteraceae subtribe Machaerantherinae. This clade contrasts with its closest relatives, the eurybioid asters, in having base chromosome numbers of x = 6 or lower, comprising a high proportion of annual species, and being adapted to arid environments. I first estimate rates of chromosome number evolution in this clade and its relatives, generating a time-calibrated phylogeny for the purpose. I demonstrate the existence of a distinct rate regime in the Machaerantherinae, characterized by rapid descending dysploidy and very low rates of chromosome number increase. This rapid descending dysploidy is shown to be attributable in part to the frequency of annuals, as they exhibit rates of descending dysploidy over ten times higher than perennials in this group. Finally, I examine biogeographical drivers of chromosome number variation in a test of the hypothesis that low chromosome numbers are favored in outcrossing annuals in unstable habitats. Path analyses provide support for the predicted relationship between aridity and low chromosome number and additionally suggest a role for UV-B radiation in facilitating this evolution. Taken together, these results provide some support for one hypothesis for chromosome number reduction while rejecting another. Namely, arid habitats and annual life history do appear to be associated with the evolution of low chromosome numbers
Investigating Computational Methods for Predicting Aerodynamic Heating in Hypersonic Flows
No full textThis thesis investigates computational and theoretical methods for predicting aerodynamic heating over blunt bodies under both low- and high-enthalpy conditions. Low-enthalpy cases for a hemispherical geometry were analyzed using SU2 under perfect gas assumptions, while high-enthalpy cases included both hemispherical and cylindrical configurations simulated with SU2-NEMO to account for thermochemical nonequilibrium effects. The study integrates CFD simulations, classical heat-flux correlations, and experimental data to evaluate prediction accuracy, examine the influence of mesh resolution and wall catalyticity, and validate results against theoretical benchmarks such as the Fay–Riddell correlation.A detailed grid convergence study confirmed the strong influence of mesh quality on heat flux predictions, particularly in capturing boundary-layer gradients. Optimal meshes were identified by considering first-cell spacing and axial-to-radial cell distribution to achieve accurate gradient resolution while managing computational cost. Under low-enthalpy conditions, CFD predictions showed excellent agreement with Fay–Riddell and experimental data, with errors as low as 1.1 %. For high-enthalpy conditions, fully catalytic CFD solutions correlated closely with experimental results, while theoretical predictions tended to underpredict heat flux. Despite the assumptions and simplifications required for thermochemical nonequilib- rium cases, Fay–Riddell proved to be a reasonable benchmark for stagnation-point heat flux in both low- and high-enthalpy regimes. Sensitivity studies revealed that viscosity models (Chapman–Enskog vs. Sutherland) had negligible impact on freestream properties and heat flux, validating Sutherland’s law for this work. Flux-scheme analysis showed that AUSM introduced nonphysical temperature diffusion near the stagnation region, whereas AUSM+up eliminated this issue and was adopted for all final simulations. Several limitations were identified, most notably the persistent “dip” phenomenon where the maximum heat flux occurs slightly downstream of the stagnation point. This anomaly was mitigated by mesh refinement but not eliminated entirely. It was also observed to vary with freestream pressure and is hypothesized to be influenced by the absence of shock-aligned meshes. This research establishes a validated CFD framework for hypersonic heat-flux prediction and emphasizes the importance of mesh quality, catalyticity modeling, and accurate thermochemical assumptions. These findings advance open-source CFD methodologies for hypersonic vehicle design and thermal protection system optimization
A Modelbuilder Workflow for Automating Contour Generation from High-Resolution Elevation Data in a Mosaic Dataset
No full textThis project streamlines the topographic-contour generation process for the New Mexico Bureau of Geology and Mineral Resources (NMBGMR). Historically, the NMBGMR generated contours internally to leverage access to high-resolution elevation rasters and maintain control over the level of detail and smoothness. Creating contours from elevation data involves a multi-step workflow requiring manual input, mosaicking, reprojecting, clipping, appending data, field calculations, and generalization. This work develops an automated geoprocessing tool using ModelBuilder in ArcGIS Pro, replacing manual steps with a simplified, repeatable process. The model uses a mosaic dataset to efficiently manage the multiple raster tiles used to generate contours. Integrated into the tool is the optional capability of unit conversion, allowing for the creation of contours in either meters or feet, automated clipping to a designated map extent, contour creation at designated intervals, appending to an existing feature class, and attribute calculations. Testing on map areas with steep, mountainous terrain confirmed that the model accurately replicates the original workflow while reducing complexity. The outcome is a user-friendly tool that standardizes contour creation and improves the efficiency of GIS specialists/cartographers when building map kits used by field geologists. This advancement allows for consistent and rapid production of accurate, map-scale appropriate contours to provide topographic context for the overlying geologic data and supports the production of high-quality cartographic layouts.This item is part of the MS-GIST Master's Reports collection. For more information about items in this collection, please contact the UA Campus Repository at [email protected]