Marshall University Music Department Presents a Senior Recital, Tyler Davis, tuba

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Health Experiences in the LGBTQ+ Community: An Ethnographic Analysis with Recommendations

This article aims to share and raise awareness of LGBTQ+ realities in healthcare. It explores the reality of discrimination and disparities in healthcare faced by LGBTQ+ people and recommendations to work towards a system that recognizes the unique challenges and circumstances LGBTQ+ people face that are influenced by social and environmental factors. This article uses Amartya Sen’s Capability Approach (1979), as well as Martha Nussbaum’s revisions to that approach (2011), and Urie Bronfenbrenner’s Ecological Systems Theory (1979) to analyze the experiences of participants who are LGBTQ and healthcare professionals. This article also uses Glynos and Howarth’s model of practices and regimes (2008) and Kimberle Crenshaw’s intersectional theory (1989). Lastly, this article offers recommendations suggested by interviewees and informed by research

Role of Salinity in Perfluorooctane Sulfonate (PFOS) Bioconcentration between Aquatic Species and the Differential Regulation of Transporters in Fundulus Heteroclitus

Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant that is known for its surfactant properties and its resistance to degradation. The persistence and lipophilicity of PFOS in surface waters have led to its bioaccumulation in fish, which in turn leads to its accumulation and toxic effects in humans that consume fish. PFOS is also hypothesized to perturb reproduction and survival of low and mid-trophic level zooplankton species such as Daphnia magna that are food for multiple fish species. In this study, a 21-day D. magna chronic toxicity test was performed using 1,10, 100, 1000, and 5000 ppb of PFOS to determine the concentration of PFOS in the whole body and its effects on fecundity, survival, and estimated population growth. PFOS showed concentration dependent decreases in survival and fecundity in D. magna and reduced reproductive success at concentrations above 10 ppb of PFOS. Salinity is a physiochemical property of water that can potentially enhance PFOS accumulation due to the presence of ions such as Ca+ and Mg2+ in the water; however, the difference in PFOS bioconcentration between freshwater and saltwater fish is not well studied. Estuarine fish species Fundulus heteroclitus (mummichog) is known for its adaptation to both hypertonic and hypotonic environments, which makes it an ideal organismal model to determine differences in the bioconcentration of PFOS in saltwater compared to freshwater in the same species. F. heteroclitus were adapted to both saltwater (23-26 ppt) and freshwater (moderately hard water; 0.143 ppt) conditions for 30 days before being treated with PFOS for 20 days to determine if bioconcentration of PFOS is higher in the liver, gills, and muscle of saltwater mummichogs compared to freshwater-acclimated mummichogs. At 100 ppb, PFOS bioconcentrations were higher in saltwater versus freshwater in the liver and muscle of F. heteroclitus. At 1 ppb PFOS and below, some of these effects were reserved but rarely statistically significant. The physiological adaptability of F. heteroclitus in different environments is facilitated by changes in expression of ionic and xenobiotic transporters within the gills. The glucocorticoid receptor (GR) showed significant decreases in mRNA expression when exposed to PFOS in saltwater mummichogs which can lead to disruption in downstream signaling of the cystic fibrosis transmembrane receptor (CFTR). Bioconcentration factors for F. heteroclitus and D. magna were determined and concentrations in the liver and gills of both saltwater and freshwater-acclimated mummichogs were compared to D. magna. In general, PFOS accumulation was greater in F. heteroclitus than in D. magna in the liver but was greater in D. magna in the muscle. In conclusion, PFOS accumulation is exacerbated by salinity at high concentrations in the tissues of F. heteroclitus and PFOS hinders reproductive success in D. magna

Effects of exposure to low, ecologically relevant doses of atrazine on somatic and gonadal development in American toad (Bufo americanus) tadpoles

Atrazine is the most commonly used herbicide in the United States, with 80 million pounds applied annually, making it the most common contaminant of ground and surface water nationwide. It has been shown to act as a potent endocrine disrupter in amphibians, causing altered somatic and gonadal development in the ecologically relevant part per billion range; as a result, it has been hypothesized that atrazine may be a major factor behind amphibian declines. However, responses of different species to the chemical vary widely, and have made predicting susceptibility difficult. Recently, it has been shown that life history can serve as a strong predictor of vulnerability, as the speed of somatic development and the timing of gonadal differentiation may determine the effects of exposure. However, previous studies leading to these conclusions have examined atrazine under stable laboratory conditions, although it is widely accepted that chemical contaminants can interact synergistically with natural stressors in the wild, producing exaggerated effects. To test whether more stressful conditions alter the effects of atrazine with respect to existing data, we raised Bufoamericanus tadpoles under more stressful conditions, including a high larval density and simulated pond drying, and exposure to ecologically relevant doses of atrazine (0, 0.1, 1, 25 ppb). We measured markers of somatic development (mass, time, survival at metamorphosis) and gonadal differentiation (ovarian stage in females, presence of testicular oocytes in males). Our results do not suggest that stressful conditions worsen the effects of atrazine, as only mass at metamorphosis was affected by exposure. Our results are interesting, however, in that they support the hypothesis that atrazine displays a non-monotonic dose-response curve, with very low concentrations (0.1,1 ppb) producing the most severe effects, an important implication for any conservation policy regarding the chemical

Electrophoretic Characterization of Carbon Nanotubes: Elucidation of Surface Functionalization and Interaction

Carboxylation of multiwall carbon nanotubes is used to enhance physical properties by improving dispersion, increasing compatibility and providing an interface for surface interaction. Accurate characterization of the multiwall carbon nanotubes surface is important as multiple applications depend on controlled functionalization. This dissertation is based on research that led to the adaption, validation and application of a capillary electrophoresis method for characterization of surface modification and interaction of carboxylated multiwall carbon nanotubes. The affinity based method uses electrostatic interaction of a selective peptide probe (WRWWWW) with multiwall carbon nanotubes to determine the degree of carboxylation. A 20% RSD in method reproducibility and repeatability was determined using within and cross day sample analysis. Method validation performed with two commercially available multiwall carbon nanotubes samples showed a significant difference in carboxylation, which was confirmed with X-ray photoelectron microscopy. In addition, the method was applied to assess the degree of carboxylation of acidified pristine multiwalled carbon nanotubes. A significant decrease in apparent dissociation constant was determined with increased acid treatment time, while no significant difference was determined using zeta potential analysis. Furthermore, capillary electrophoresis was also applied to isolate key factors that govern the interaction between multiwall carbon nanotubes and amino acids, arginine and tryptophan. For this analysis, the peptide probe was substituted with peptides containing either single or multiple amino acid substitutions or deletions. The study showed a two-fold increase in an electrostatic interaction of arginine in comparison to lysine and increased hydrophobic interaction with tryptophan chain length, revealing that both arginine and tryptophan drive peptide-carbon nanotube interactions. This method, for the first-time, allows for quantification of the individual contributions of amino acids and characterization of bulk multiwall carbon nanotubes samples with capillary electrophoresis. This research is significant to the study and development of nanotube-biomolecule applications and provides a cost-effective, rapid and simple alternative to current methods

Doctor of Philosophy

dissertationThis dissertation provides an in-depth evaluation of microstimulation of the primary visual cortex (V1) using chronically implanted Utah Electrode Arrays (UEAs) in macaque monkeys for use as a visual prosthesis. Within the scope of this dissertation are several significant contributions. First, a minimally invasive and robust device for head fixation was developed. In comparison to other available designs, this device improved long-term outcomes by providing a stronger, less invasive interface that reduced the risk of infection. This device made it possible to acquire chronic microstimulation data in macaque monkeys. It has been tested on three animals and has provided a stable interface for over two years. Second, this dissertation is the first to describe the factors influencing the performance and safety of microstimulation of V1 with the UEA. Two UEAs were implanted in V1 of two macaque monkeys, and experiments were performed several months following implantation. The electrical and recording properties of the electrodes and the high-resolution visuotopic organization of V1 were measured. In addition, threshold stimulation levels that evoked behavioural responses using single electrodes were determined. Periodic microstimulation at currents up to 96 pA did not impair the ability to record neural signals and did not affect the animal's vision where the UEAs were implanted. It was discovered, however, that microstimulation at these levels evoked behavioural responses on only 8 of 82 systematically stimulated electrodes. It was suggested that the ability to evoke behavioral responses may depend on the location of the electrode tips within the cortical layers of V1, the distance of the electrode tips to neuronal somata, and the inability of nonhuman primates to recognize and respond to a generalized set of evoked percepts. Finally, this dissertation is the first to describe the spatial and temporal characteristics of microstimulation of V1 with the UEA over chronic time periods. Two years after implantation, it was found that consistent behavioural responses could be evoked during simultaneous stimulation of multiple contiguous electrodes. Saccades to electrically-evoked targets using groups of nine electrodes showed that the animal could discriminate spatially distinct percepts with a resolution comparable to the current epiretinal prostheses. These results demonstrate chronic perceptual functionality and provide evidence for the feasibility of a UEA-based visual prosthesis for the blind

Passive Unaccusatives In L2 English

Passive unaccusativity refers to a phenomenon whereby L2 English speakers produce unaccusative verbs in passive constructions. Since unaccusative verbs are a subset of intransitive verbs and thus generally do not passivize, the question of how learners recognize unaccusatives without any overt input distinguishing subsets of intransitives has piqued the interest of many researchers since the late 1970\u27s. Oshita\u27s (2000) claim that passive unaccusatives are NP-movement markers is now a widely accepted claim; however, studies of more general characteristics of intransitivity have revealed close parallels between passive unaccusatives and other well-documented phenomena. The aim of this paper is to show that passive unaccusativity patterns with these other more general phenomena. A corpus of essays written by L2 English speakers was used for this purpose, yielding mixed results. Oshita\u27s claim was not supported while predictions given more general characteristics of intransitive verbs were only minimally supported

The Water Table, Soil Moisture And Evapotranspiration Conditions Following The Removal Of Conifers From Two Encroached Meadows

Montane meadows provide essential habitat for a variety of unique species and important ecosystem services in the western United States. Although important, meadows have experienced increased rates of conifer encroachment due to climate change, fire suppression and grazing. To combat meadow degradation from conifer encroachment, land managers have employed various restoration strategies one of which is conifer removal. Multiple studies have investigated the relationship between meadow hydrology and vegetation; however, few have assessed the effect of conifer removal on meadow groundwater. The goal of this study is to determine if the removal of conifers from an encroached meadow has an effect on depth to the groundwater table (WTD) and soil moisture content (SMC), and to investigate the accuracy and potential usefulness of evapotranspiration (ET) calculation methodologies for montane meadows. This goal will be accomplished by the subsequent objectives: 1) perform an analysis of WTD and SMC in an encroached meadow preceding and following conifer removal and upland thinning; 2) calculate and compare daily ET estimates in a previously restored meadow using diurnal groundwater table fluctuation, diurnal groundwater fluctuation modelling, and SMC. Miranda Cabin Meadow (MC) is located within the Upper American River Watershed, southeast of French Meadows Reservoir, at an elevation of 6,200 feet. MC received conifer removal, upland thinning and road decommissioning in the fall of 2018 as part of the American River Conservancy’s American River Headwaters Restoration Project. This study found the average WTD in MC during the growing season decreased from 4.91 feet prior to restoration, to 3.39 feet after restoration. In addition, the number of days the WTD was within 0.98 feet and 3 feet increased from 12 days and 34 days, to 31 and 49 days. Analysis of SMC in MC was limited due to gaps in data, however this study found that after restoration the average weekly SMC decreased at a slower rate than prior to restoration, possibly indicating decreased hydrologic output from ET. Based upon WTD during the growing season and the limited SMC data it appears that removal of conifers and upland thinning at MM promotes SMC and WTD conditions conducive to meadow vegetation communities. Marian Meadow (MM), located in Plumas County, CA at an elevation of 4,900 feet, received conifer removal as part of a timber harvest plan carried out by Collins Pine Company in July 2015. The soil moisture sensors used in this study were installed in MM in September 2013 for previous graduate thesis research. Groundwater table data was collected using 10-foot wells installed in July of 2018. Daily ET was calculated during August 2018 using three methodologies, and during September 2018 using two methodologies. Daily ET estimates calculated using diurnal groundwater table fluctuation and the White method averaged 11.8 mm per day in August and 9.1 mm in September. Using diurnal groundwater table fluctuation modelling this study calculated an average daily ET of 4.2 mm in August and 3 mm in September. Daily ET estimates based on SMC were calculated for August 2018 using two methods which produced estimates of 0.9 mm and 1.2 mm per day. All three methods for calculating ET produced some daily estimates that compare well to previous research of Et in Sierra Nevada meadows, however the White method generally overestimated daily Et while SMC methods underestimated ET. Groundwater table fluctuation modelling produced the best estimates of daily ET for both August and September. ET results in this study support previous research on the applicability of the White method; and they also suggest that the applicability of groundwater fluctuation modelling to estimate meadow daily ET in Sierra Nevada montane meadows be investigated further

Conservation status of the forest birds of the Siria Plateau and western Maasai Mara, Narok County, Kenya

In light of rapid deforestation across the Siria Plateau of southwest Kenya, we compile records and review the status and distribution of locally occurring forest dependent birds there. Records of forest birds in the western reaches of the Maasai Mara National Reserve are also included for reference, and bird richness in the area is briefly contrasted with that of other forests of southwest Kenya. Included in this review is a first account of the forest birds of the 1500-ha Nyakweri Forest.Keywords: Deforestation, Biodiversity, Migori River, Inventory, Forest bird