LAS Theses and Dissertations
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Item Dung beetle (Coleoptera: Scarabaeinae) community diversity: Influence of grazing regimes and dung type in a grassland ecosystem(Wichita State University, 2024-07) Woodard, Bryanna Grace; Jameson, Mary LizDung beetles (Coleoptera: Scarabaeinae) are critical ecosystem engineers that improve grasslands through waste removal, bioturbation, and carbon sequestration. Therefore, grassland management that supports diverse dung beetle communities is essential for maintaining the sustainability of these ecosystems. Historically, grasslands in the Great Plains region were home to keystone herbivores such as bison (Bison bison bison Linnaeus), but as agriculture spread due to European expansion, bison were extirpated and replaced with cattle (Bos taurus Linnaeus). Dung beetles are closely associated with these large herbivores because they break down and distribute their dung, contributing to key ecosystem services such as nutrient cycling and reduced pasture fouling. In rangelands, pastures are managed with grazing herbivores, haying and mowing, or they are fallow (ungrazed), which allows for woody plant encroachment. To date, few studies have examined the effects of dung type on dung beetle communities and no studies have examined these effects under different management regimes. We examined dung beetle community structure and composition on bison-grazed, cattle-grazed, and ungrazed pastures at two study sites in the northern Flint Hills tallgrass ecoregion in Kansas, USA. Dung beetle community data were collected using pitfall traps baited separately with either bison, cattle, or rabbit dung. Redundancy analyses showed that dung beetle communities associated with each dung type and grazing regime differed. These results suggest that different management regimes support diverse, abundant dung beetle communities, and multiple species of herbivores are needed to support these communities, as no dung type was able to attract all species. Our findings highlight the importance of grassland management plans that implement a mosaic of grazed and ungrazed patches to maximize dung beetle diversity, thus benefiting the ecosystem services of this critically imperiled ecosystem.Item Magnetic field simulation studies in the muon spectrometer(Wichita State University, 2024-07) Shivakoti, Sushil; Muether, MathewThe Deep Underground Neutrino Experiment (DUNE) is focused on addressing important questions in neutrino physics such as matter-antimatter asymmetry and neutrino mass. The experiment utilizes advanced technologies to study muon neutrino disappearance ( ) and electron neutrino ( e) appearance events. An important challenge is distinguishing wrong-sign events, such as antineutrinos, in a neutrino beam. The magnetized TMS is crucial for differentiating muons and antimuons, which allows for accurate oscillation rate predictions.Our study examines the impact of magnetic fields on charge identification in the TMS. Our goal is to determine the optimal field strength for accurate charge determination. We have developed a signed distance metric for charge identification: S.D>0 (for muons) and S.D<0 (for antimuons). We discovered that higher magnetic fields increased the signed distance, which improved the particle’s charge identification. Additionally, as opposed to lower momentum and lower magnetic fields, particle recognition was better at the low momentum range and higher magnetic fields, and even better results were achieved at higher magnetic fields and higher momentum ranges by reducing overlap between the distributions. Plots of Fraction vs. True muon kinetic energy and Fraction vs. momentumTMSStart demonstrate improved charge particle identification with increased magnetic field values.Item Exploration of the optical properties of heteroanionic compounds(Wichita State University, 2024-07) Jiao, Zixian; Wang, JianNonlinear optical (NLO) materials can convert light from one wavelength to its half wavelength, resulting in the enhancement of the light energy (talking about single photon here, doubled frequency for new photons) through a process called second harmonic generation (SHG). SHG can be simply explained as two photons with the same frequency interact within the NLO material and are combined, forming a new photon with the doubled frequency (half wavelength) of the initial two photons. Due to this unique optical property, these kinds of materials can be utilized in a wide field, for instance, they can be employed in lasers for frequency conversion techniques where infrared lasers can be converted to visible outputs and they can also be used to strengthen the capability of optical communication system by generating a new light with higher frequencies, etc. Due to the structural diversity and the emerging plentiful physical properties of heteroanionic compounds, they have become popularly investigated nonlinear optical materials (NLO). In this work, the synthesis, characterization, and analysis of the related properties of three different systems of NLO heteroanionic compounds are presented and discussed. By investigating and comparing different NLO heteroanionic compounds and their related optical properties can not only provide strategies and inspirations of designing and synthesizing new and better qualified NLO materials but also can enrich the knowledge and the understanding of the related nonlinear or linear optical properties.Item The sexual psychopath: Masculinity, gender variance, and paranoia in the twentieth century(Wichita State University, 2024-07) Brouillette, Christen H.; Henry, RobinThis thesis investigates the creation of the sexual psychopath, its very specific definition, and the laws which were created to restrain them. Newspaper articles and primary and secondary sources regarding the evolution of psychology, childhood, masculinity, and sexuality were used, as well as crime statistics from the 1930s to form and support the argument. The sexual psychopath included homosexuals, pedophiles, and elderly men who attacked young women but excluded men of color and adult men who attacked adult women. This normalized sex crimes committed against women and targeted homosexuals under the guise of protecting women. Despite public outcry to protect children from sex criminals in the mid-1930s, court officials underutilized sexual psychopath laws and even sought to narrow the definition of statutory rape. This made it clear that despite legislators claiming to have children’s best interest at heart, the laws created to protect them were instead used to target ‘aberrant’ populations such as homosexuals and punish them. This thesis also examines the rhetoric used to demonize homosexuals and finds that since the panic of the 1930s, very little has changed. This is explored through the founding of the Save Our Children organization and Anita Bryant’s efforts to roll back protections for homosexuals in the late 1970. Therefore, I suggest that fears about the sexual psychopath stemmed from cultural anxieties about fluctuating definitions of masculinity and homosexuality. These groups identified children as a population that needed protection from the sexual psychopath and limited their definitions of sexual psychopath to particular groups, specifically single and gay men. This effort to stabilize healthy expressions of masculinity and assuage those fears ended up stunting sexual expression and contributing to socialized homophobia and fear of single, gay men, fears that continue into the present day.Item Unveiling the role of cancer-associated fibroblasts in head and neck squamous cell carcinoma (HNSCC) in the development of a human patient "avatar" system(Wichita State University, 2024-07) Adeniji, Omolade Monisayo; Hendry, William J. IIIHead and neck squamous cell carcinoma (HNSCC) is a diverse cancer with high molecular and clinical heterogeneity. HNSCC is the sixth-most common cancer worldwide, with 890,000 new cases and 450,000 deaths. Despite the intense work of scientists to advance the field of medicine, HNSCC patients' overall survival (OS) remains below 50%. This is mostly because of treatments failure, poor prognosis, and a limited number of pre-clinical models that can be used to study and show how HNSCC works. Our study aimed to use a hamster PDX model for HNSCC by creating spheroids/organoids (S/Os) from two HNSCC cell lines (CAL-27 and FaDu) and then classify them at the proteome level. We also cultivated cancer-associated fibroblasts (CAFs) in 2D cultures to prepare them for transplantation alongside the S/Os. Finally, we used histology and IHC to see how well these S/Os and CAF cells work in the xenotransplantation system. Our findings show that incorporating CAFs with HNSCC S/Os has a substantial effect on transplant mass growth and progression in the PDX model. We also assessed the expression of specific proteins (AR, p-FAK, CD133, CD44, CD8α, NFkB, PCNA, P53, Ki-67, HOX11, TR4, and YY1) in the donor S/Os and transplant masses. The results indicate that CAFs can impact particular cellular processes, including proliferation, adhesion, and immune response and the marker proteins’ differential expression and location reveal potential therapeutic targets and provide insight into the processes by which CAFs may advance HNSCC. Our findings conclude that incorporating CAFs with HNSCC S/Os influences tumor growth and progression in the hamster xenotransplantation model and that this model shows effectiveness for the preclinical studies of HNSCC.