The LAIR at East Texas A&M
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Long Term Effects of Jim Chapman Reservoir on Upper Sulphur River Fish Communities
No full textReservoirs, along with their importance in the modern ecosystem and economic development, bring a serious alteration in the natural habitat of fish communities. Understanding their impact on fish communities can help in supporting fish conservation. However, studies on reservoir impact on fish communities are mostly limited to short time scales and more long-term studies are needed for more comprehensive understanding of impacts. We compared fish communities of upper Sulphur River tributaries in 2024 with pre-impoundment surveys in the same region conducted in 1971. Jim Chapman reservoir was built in 1986 and isolates upstream Middle, and upstream South Sulphur sections from the rest of the system. Twenty-five sites from upstream Middle, upstream South Sulphur, above the lake, and non-fragmented locations (mostly North Sulphur) were sampled using standardized surveys with backpack electrofishing and seine nets from February 2024 to September 2024. Data were analyzed using non-metric dimensional scaling (NMDS), analysis of similarity (ANOSIM), a modified regionally calibrated index of biotic integrity (IBI), analysis of similarity percentage (SIMPER), indicator species analysis, species richness, Shannon diversity index, Jaccard distance of similarity and regional abundance. The analysis showed that two species, Cyprinella lutrensis and Carpiodes carpio, were significantly reduced over the years including likely complete extirpation of Cyprinella lutrensis in the Upstream Middle Sulphur section. Additionally, fish communities seem to have homogenized since 1971 across regions and ~56% of fish species were common in all two or three of the regions. The Sulphur River system had ~36% species richness increase compared with the 1971 study (likely impacted by addition of electrofishing data), but despite this trend, the Upstream Middle Sulphur had a negative community shift with ~29% decline in species richness and lowest regional modified IBI score. Upstream South Sulphur showed relatively high diversity and included the presence of Phenacobius mirabilis, a species of conservation needs in Texas, despite being isolated above the lake, possibly related to it being a larger system than the Middle Sulphur that can better withstand drought. Centrarchidae species like Lepomis aquilensis, Lepomis macrochirus and Lepomis cyanellus and mosquitofish Gambusia affinis were indicator species in the 2024 samples, replacing Carpiodes carpio and Cyprinella lutrensis which were the indicator species of the 1971 samples. These findings suggest that the stream size is significant in shaping fish communities upstream of the impoundments, and indicates a possible relationship between stream size, drought, and available refugia in connected flowing systems as driving ecosystem resilience to declines in species richness. Homogenization across the three regions may have been driven by compounded effects from long-term modifications such as channelization, reservoir construction, agricultural land use, high annual variability in flows, and increasing drought events. Further studies could address patterns and causes for the declines for Cyprinella lutrensis (Middle Sulphur) and Carpiodes carpio (Upper Sulphur River). Finally, the patterns seen in the Upper South Sulphur suggest that it had the capacity to conserve diverse fish communities including species of conservation need like Phenacobius mirabilis, thus, any water projects in that section are not recommended
Automated 3D Printing Defect Detection and Correction Using Machine Learning
No full textThree-dimensional (3D) printing is an innovative additive manufacturing technique that creates a 3D physical product from a digital design using layer-by-layer addition, enabling the possibility of the creation of complex geometries with high precision and customization. In recent years, it has been developing very quickly, with new technologies and applications emerging across a variety of industries including Aerospace, automotive, manufacturing, robotics, and education. Along with the growth in the adoption and integration of 3D printing across various industries, there is a pressing need to have high-quality 3D printing. Even a minor printing error and/or defect can compromise the project quality and result in substantial waste and added costs from reprints, material losses, and production delays. However, less attention has been given to the understanding of 3D printing defects and defect detection. Additionally, the absence of defect data has created a critical research gap, limited insights, and hindered the progress of research efforts. This research focuses on developing an automated defect detection system using machine learning. The study defines key 3D printing defects and correlations with their underlying causes, including hardware issues (e.g., nozzle clogs, misalignment), material problems (e.g., filament moisture), software misconfigurations (e.g., incorrect print speeds, G-code errors), environmental factors (e.g., temperature fluctuations), and user errors (e.g., improper calibration). Based on it, we then build a 3D printing system as a prototype to fill the identified gaps by collecting real 3D printing data and enabling automated 3D printing defect detection. Using both newly collected data and publiclyavailable datasets, eight machine learning algorithms (Alexnet, ConvNeXt, EfficientNet, GoogleNet, Resnet, Swin Transformer, VGG Net, and Vision Transformer) are trained and tested to detect defects, even on incomplete prints. The results demonstrate the potential for real-time error detection and correction, shedding light on future autonomous 3D printing systems for defect correction with minimal human intervention
What Leadership Practices Lead to the Development of Early Career Teachers? A Collective Case Study of Novice Teachers’ Perceptions and Experiences
No full textAs school leaders face ongoing challenges of teacher shortages and novice teachers entering the profession encounter unique trials, it is important to explore which leadership behaviors and practices novice teachers from a campus with higher teacher retention describe as valuable to their support and development. Knowing that leadership support and professional development can improve teachers\u27 pedagogical and instructional practices (Di Domenico et al., 2019), further research needs to be conducted to gather teachers’ perceptions about the role leadership strategies have played in their continued growth and development. This study will also explore how these teachers make meaning of such support in relation to their own teaching self-efficacy and their intentions to continue teaching
Regulation of the Pyrimidine Biosynthetic Pathway In Pseudomonas Lemonnieri
No full textThe focus is on the regulation of the pyrimidine biosynthetic pathway in a soil bacterium. The five pathway enzymes unique to pyrimidine formation are aspartate transcarbamoylase, dihydroorotase, dihydroorotate dehydrogenase, orotate phosphoribosyl transferase, and orotidine 5\u27-monophosphate (OMP) decarboxylase. The impact of 0.4% carbon source and pyrimidine base supplementation on the pyrimidine biosynthetic enzyme activities in the bacterium Pseudomonas lemonnieri ATCC 12983 was determined from enzyme assays. The bacterial cells will be grown in a minimal medium containing 0.4% glucose or sodium succinate as a carbon source and either 50 milligrams/liter of uracil or orotic acid. The late exponential phase-growing cells are collected by centrifugation, ultrasonically disrupted with the cell extract, then centrifuged, followed by dialysis overnight at 4°C. The carbon source impacted the de novo pyrimidine biosynthesis pathway in P. lemonnieri ATCC 12983 by exhibiting higher activities in the glucose medium compared to the succinate medium except for the OPRTase activity. An examination of uracil or orotic acid addition to the culture medium assay was investigated. It was found that pyrimidine addition to the medium affected biosynthetic enzymes differently with carbon source being a factor. After these studies, the isolation of pyrimidine auxotrophic strains using chemical mutagen ethyl methyl sulfonate (EMS) and resistance to 5-fluoorotic acid and 1 milligram/liter uracil. The colonies on the plates were screened for uracil auxotrophy following 96 hours at 300C. Compared to the pyrimidine biosynthetic enzyme activities in uracil-supplemented ATCC 12983 glucose-grown cells, OPRTase or OMP decarboxylase activity was observed to be deficient in the cell extracts of individual mutant strains. Characterization of the uracil requiring mutant strain\u27s growth on solid glucose or succinate minimal medium revealed that either cytosine or uridine could also meet the pyrimidine auxotrophy of the strains. The mutants were limited to pyrimidine for a period of 1 or 2 hours to see the effect of the enzyme activities relative to the carbon source. The starvation experiments in glucose medium have shown increased activities when starved for 1 hour and with their activities increasing further after 2 hours except for ATCase activity. Whereas the starvation in succinate medium decreased the activities for 1 hour of limitation with 2 hours exhibiting a further significant decrease in activities. The regulation of the known regulatory enzyme ATCase activity in vitro in P. lemonnieri was determined with the Km value for L-aspartate being 2.55 (0.15) mM and carbamoyl phosphate being 0.47 (0.30) mM. The study focused on the inhibition of ATCase activity in the presence of nucleotide effectors. The highest inhibition occurred in the presence of 5 mM PPi, AMP, ADP, UMP, GMP, GTP, CMP, and CTP. In conclusion, this investigation demonstrates that the pyrimidine biosynthetic enzyme synthesis and transcarbamoylase activity were regulated in P. lemonnieri. Overall, this study provides new information regarding the regulation of pyrimidine biosynthesis by pyrimidines and related compounds in P. lemonnieri
An Exploration of Teachers’ Perceptions Regarding Shared Decision-Making and Organizational Citizenship Behavior as They Relate to Teacher Retention
No full textThe shortage of teachers in classrooms across the country is not a new problem, and research suggests that this issue has only worsened in recent years. The struggle to find and keep highly qualified teachers in our schools makes it vital to better understand what motivates teachers to remain in and thrive in the profession. The purpose of this narrative inquiry study was to explore participants’ experiences with shared decision-making and their perceptions of organizational citizenship behavior, as well as how each of these relates to their intention to remain on their campuses and in the field of education. This qualitative study included the perspectives of a sample of secondary teachers in a large suburban district in north central Texas and was conducted in two phases. In Phase 1, the researcher collected survey data from 72 participants. For the next phase, nine participants were randomly selected from the list of Phase I participants who volunteered to be included in Phase II interviews. In Phase II, the researcher dove into the narrative experiences and perspectives of participants with semi-structured, one-on-one interviews
Biofeedback As Prevention for Distress Within Traditional Undergraduate College Students: A Single-Case Research Study
No full textPost-pandemic, data show college-aged students are uniquely vulnerable to mental illness symptoms, yet rises in demand make mental healthcare services more difficult to access. The purpose for this study was to examine the effectiveness of preventative methods to alleviate current and future distress among traditional undergraduate college students, leveraging a multiple baseline single-case research design. In this study, 3 undergraduate students aged 18 or 19 participated in 9 brief data collection sessions (3 per week) where participants completed the Subjective Units of Distress scale, the Kessler Distress Inventory, and a 2-minute session with the EmWave Pro Plus heart rate monitor. The first three sessions established a baseline to which the researcher compared data from the next three sessions (treatment phase) and the last three sessions (withdrawal phase). The treatment was HeartMath’s attitude breathing technique to improve heart rate variability and establish cardiac coherence. This researcher visually analyzed the data points across the three phases of data collection (baseline, treatment, withdrawal) and calculated the points exceeding the median to determine the efficacy of attitude breathing as a self-administered treatment for distress. Results showed the treatment is debatably effective, but limitations of the study may have reduced the effectiveness of the treatment. Further research is necessary to address the effectiveness of treatments individuals can administer themselves to cope with distress. Keywords: Heart Rate Variability, distress, coherence, single-case research design, traditional undergraduate student
Probing Short Story Cycles: Interpreting Dubliners and Winesburg, Ohio Through Nietzsche’s Philosophical Concepts
No full textThis dissertation delves into the exploration of the short story cycle genre employed by modernist writers as an experimental style to illustrate the disintegration of life in the modern world. The primary focus lies on James Joyce’s Dubliners (1914) and Sherwood Anderson’s Winesburg, Ohio (1919), dissecting how these authors utilize the technique of short story cycles to depict the stagnation and paralysis characteristic of modern life. Through a comprehensive analysis of narrative techniques and thematic elements in both works, the study aims to uncover the intricate portrayal of 20th-century human beings. Recognizing that modernist literature emphasizes the individual, this study underscores the importance of understanding human nature to explore the profound depths of these literary works. Drawing inspiration from the twentieth century philosophical discourses on human nature, the dissertation specifically selects Friedrich Nietzsche, a German philosopher whose ideas significantly influenced modernist literature. Nietzsche’s insights form the foundation for a nuanced examination of Dubliners and Winesburg, Ohio, enabling a deeper understanding of recurring themes, character motivations, narrative structures, and underlying philosophical inquiries within the texts. The subsequent chapters of the dissertation apply Nietzsche’s philosophical concepts of will to power/life and giving style to one’s character to scrutinize Dubliners and Winesburg, Ohio respectively, establishing correlations between Nietzsche’s ideas and the prevalent themes of these collections. By integrating Nietzsche’s concepts, the study contends that readers can interpret the themes of stagnation and paralysis in a new light, unraveling deeper societal reflections and implications within modernist literary works. The discussion extends to illustrate how those concepts shape the narratives of Dubliners and Winesburg, Ohio while portraying the struggles of the characters. This comprehensive exploration not only sheds light on the challenges and limitations faced by people in the modern era, but also provides a new perspective on understanding the underlying themes present in modernist literary works
Testing Population Structure of Agkistrodon Piscivorus in East Texas Populations Using Microsatellite Markers
No full textReptiles generally occupy smaller geographic ranges and specialized habitats causing them to be more vulnerable to anthropomorphic impacts. Habitat fragmentation creates patch fragmentation and in some cases patch isolation. The consequences of habitat fragmentation can decrease access to mating opportunities along with the distribution of new genes to local populations. Once a population size becomes lower than their minimum viable population, the probability of inbreeding increases and genetic diversity decreases. Microsatellites are molecular markers that are highly variable because of high rates of polymorphism. The use of theoretical models allows for the testing of genetic material to gain an understanding of the genetic health of studied populations through testing for inbreeding and population genetic structure. In this study, I collected genetic material from Agkistrodon piscivorus through tail clippings from 3 locations: TAMUC Wetlands, Sulphur River and Cooper WMA. From the cottonmouth tail clippings, DNA extracted and processed using the E.Z.N.A.® Tissue DNA Kit from Omega Bio-Tek according to their instructions. Cottonmouths are a common species found within wetland habitats and have been used for microsatellite research before by using microsatellite loci PCR primers from Agkistrodon contortrix. These microsatellite loci PCR primers were used for the PCR protocol and data analysis was completed using STRUCTURE, MIGRATE, and GENALEX. Major findings of this study show the populations to not be within HWE because of the high levels of inbreeding between sampled snakes. The highest levels of genetic differentiation came from the Cooper WMA while the lowest levels were found in the Sulphur River populations. shown with the data from STRUCTURE with the use of Puechemaille method found a K 3 result which suggests that each location is a separate population but with a larger split between the Cooper WMA and the TAMUC sites. DAPC analysis using the Adgent package in R, placed the individuals into clusters based on genotype similarity and found a similar pattern. Both the TAMUC Wetland and Sulphur River had significant overlap with minor separations between one another, while the Cooper population remains separate. A Wilcoxon rank-sum test on FIS levels per locus did not find a significant difference in inbreeding levels between the Commerce locations and the Cooper WMA
A Case Study of Kindergarten Teachers Mobilizing Translanguaging to Promote Engagement, Biliteracies, and Critical Consciousness
No full textDual language bilingual education is implemented through various language models that often commodify emergent bilinguals and impose strict language separation. Focusing on language and academic performance limits students’ participation in transformative practices and hinders the development of biliteracy. Monoglossic practices disenfranchised and further marginalized emergent bilinguals academically, culturally, emotionally, and linguistically. This descriptive case study presents the ideologies and pedagogical practices of two Latinx kindergarten educators with unique language, immigration, and education experiences who resist and respond to oppressive practices in North Texas. Their pedagogical practices enact bilingual critical literacies and acompañamiento to support students\u27 academic and identity development. The study used artifacts, surveys, and interviews to reveal their ideologies and definitions of translanguaging as a pedagogical and humanistic practice. Data was analyzed using theoretical analysis and coding that reveal themes of writing definitions, translanguaging ideologies, and writing and critical consciousness practices. This study showcases the ability of passionate and informed educators to leverage translanguaging, acompañamiento, and bilingual critical literacies to foster the development of young children\u27s academic, language, and identity in restricted environments. Some challenges the educators confronted include strict language separation, monoglossic curriculum, and emphasis on standardization. The participants of this study demonstrated the importance and role of educators in supporting young children\u27s connection to their culture and communities. This dissertation has implications for educators, professional development, literacy, teacher programs, and school administrators. The study concludes with recommendations for future studies in critical consciousness, translanguaging, and biliteracy writing in early childhood
Lived Experiences in Adults with Autism Spectrum Disorder Comorbid with Intellectual Disabilities, and Other Internalizing Disorders
No full textIndividuals with Autism Spectrum Disorder (ASD) are at a heightened risk for developing further internalizing disorders. Identifying and diagnosing internalizing disorders is difficult in the general population. Among the population with ASD, situations can be more challenging due to atypical symptom presentation, due to the presence of social communication deficits in this population with comorbid disorders, such as anxiety, attention deficit-hyperactivity disorder, depression, intellectual disability (ID), and obsessive-compulsive disorder. Conceptualizing the ways these symptoms manifest can be a challenge to ascertain and specify symptoms in a clinical diagnosis. This introduces the concern of diagnostic overshadowing. The result of this can lead to misdiagnosis and inadequate treatment planning. The treatment options for adults with ASD, comorbid with intellectual disability and other internalizing disorders are scarce. Treatment options are limited due to challenges in cognition and communication, and a lack of resources and support for this population. This study was conducted at a continuing education program for adults with intellectual disabilities, some with a co-occurring diagnosis of ASD, and were determined to be at heightened risk of developing an internalizing disorder. This study aimed to provide a nuanced understanding of the lived experiences of individuals at the intersection of ASD, ID, and internalizing disorders. This was done by analyzing qualitative data from focus groups involving adults diagnosed with ASD, comorbid with ID and other internalizing diagnoses. The parents and service providers were also involved in the study utilizing focus group discussions which were conducted by qualitative analyses over focus group discussions, about the multifaceted challenges, coping mechanisms, and support needs encountered by these individuals in their day-to-day interactions and relationships. The results of this study will be beneficial in enhancing the understanding of the treatment options to effectively identify and support individuals with ASD, comorbid with ID and other internalizing disorders. The findings of this study identified three consistent themes between all informant groups; symptoms identification, support, and treatment barriers. The themes identified by the informants help us better understand the lived experiences of individuals with ASD, comorbid with ID, and other internalizing disorders