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Environmental Surveillance of Antimicrobial Resistance in Commercial Poultry Production: Microbiome, Resistome, Antimicrobial Residues, and Avian Pathogenic Escherichia coli Dynamics
No full textAntimicrobial Resistance (AMR) is a major global threat to humans, animals, and the environment, often driven by overuse of antimicrobials and environmental contamination, particularly in food animal production. We focused on using the vertically integrated poultry production system as a model to understand the AMR dynamics. Environmental samples representing the inside poultry house (litter) and outside environment (soil and wild or domestic animal fecal samples surrounding the poultry houses) were collected from different stages of production including pullet, breeder and broiler farms. Additionally, flocks from broiler farms were followed to their respective processing plants to collect carcass rinses from post-pick and post-chill stages.
The introductory review chapter underscores the importance of environmental reservoirs in shaping the AMR persistence and development, suggesting the need for comprehensive environmental monitoring for tackling AMR. Further, investigation using shotgun metagenomics revealed distinct microbiome and resistome profiles across different stages of production and environmental samples. Moreover, isolated instances of microbiome and resistome overlap between inside environment and outside poultry house environments were observed, suggesting potential biosecurity breaches.
Complementing metagenomics finding, qPCR analysis demonstrated a higher AMR burden in the litter compared to soil samples particularly in broiler farms. Metagenomics resistome and qPCR results corraborated with each other, both offered insights on AMR diversity and quantification. Furthermore, antimicrobial residue analysis provided opposite trends: antimicrobial residues such as sulfamethoxazole, tetracycline and, oxytetracycline were detected in higher quantity in the early stages of production (pullet and breeder) than in broiler farms. While antimicrobial residues were not associated with antimicrobial resistance genes (ARGs) levels, residues were positively associated with quantification of mobile genetic elements (MGEs), thereby indicating antimicrobial residues may facilitate AMR dissemination via horizontal gene transfer.
Our final approach was to use the culture dependent technique to investigate the prevalence and genomic characterization of avian pathogenic E. coli (APEC), a potential marker organism for AMR surveillance in poultry production settings. APEC was widespread and carried clinically relevant ARGs among different stages of production and sample types. We identified high-risk APEC strains in the farms’ environment as well as in the processing plant. Single nucleotide polymorphism (SNP)-based phylogenetic analysis provided compelling evidence of potential APEC transmission between the inside farm environment and adjacent outside area, as well as between broiler farm litter and processing plant.
Overall, these comprehensive studies highlight the multifaceted and complex nature of AMR. The farms’ environment can act not only as a reservoir of AMR but also as a potential source of AMR spillover. This dissertation highlights the value of a multi-technique approach that integrated metagenomics, qPCR, antimicrobial residue detection, and culture-based technique to comprehensively understand the dynamics of AMR
A Phenomenological Study of School Personnel Experiences with Trauma-Informed Practices
No full textThis qualitative phenomenological study examined the lived experiences of school personnel in an alternative school setting within a large urban school district in central Alabama. The study explored how faculty and staff interact with and implement trauma-informed practices and curricula in alignment with the Missouri Model for Trauma-Informed Schools. The research was grounded in the Substance Abuse and Mental Health Services Administration’s (SAMHSA) definition of trauma and informed by existing trauma-responsive programs utilized within the district, including Adversity University and RethinkEd. The participant cohort included eight veteran educators serving a predominantly African American student population, most of whom are considered at-risk due to socioeconomic status, exposure to community violence, and disciplinary infractions that meet Class III behavioral violations. Data were collected through semi-structured interviews and analyzed using thematic coding and the hermeneutic phenomenological framework of Heidegger, allowing for a deep exploration of participant perspectives. Findings revealed seven key themes: the centrality of relationships, the role of surrogate familial connections, personal trauma references by educators, perceived insufficiency in training, situational versus root-cause responses, lack of district-level professional development, and the pervasive presence of trauma among students. Participants expressed a strong desire to support students but reported feeling underprepared to address trauma effectively due to inconsistent training and limited access to qualified mental health professionals. Based on the Missouri Model’s continuum, the school was determined to be functioning at the “trauma-sensitive” stage, characterized by informal references to trauma and early-stage implementation of trauma-informed strategies. This study contributes to the limited body of research that captures the voices of educators working directly with traumatized youth in alternative settings. The findings underscore the need for more comprehensive, ongoing professional development and the integration of trauma-informed approaches into all aspects of school culture, policy, and instruction
Understanding the decision factors and decision-making styles of selecting and using over-the counter medications to treat common minor ailments among young adults
No full textIntroduction: The prevalence of inappropriate use of over-the-counter (OTC) medication is 20-50%. Young adults are at a unique developmental and transitional life stage that makes them vulnerable to inappropriate use of OTC when they select and use OTC to treat common minor ailments (CMAs). To design an intervention to support young adults to make OTC decisions, it is important to understand the decision-making process of the end-user to tailor the components of the intervention to meet their needs.
Objectives: To explore the OTC selection and use decision-making process among U.S. young adults, including investigating factors involved in OTC decisions, the decision-making steps, and the interplay among decision factors, decision-making styles (DMSs), and inappropriate use of OTC.
Methods: A scoping review was conducted to identify a comprehensive list of factors involved in OTC selection and use decisions among adults in the U.S. (Aim 1). Semi-structured interviews with young adults were conducted to elucidate the decision-making process of selecting and using OTC to treat CMAs (Aim 2). A cross-sectional study was conducted to assess the association between DMSs, decisional factors, and inappropriate use of OTC to treat CMAs among young adults via online survey (Aim 3).
Results: This project found that multiple levels (individual, interpersonal, environmental, and drug-related) of factors were involved in the OTC medication decision-making process. The common OTC decision factors were symptoms, availability and effectiveness of the OTC medications in all adults and in young adults. Personal experience was a more commonly used information resource, preceding the drug fact label (DFL), Internet, professional healthcare providers, and others. The rate of inappropriate selection of OTC was 49.4%, and the rate of inappropriate use of OTC (i.e., Naproxen) was 79.4% in the hypothetical scenario. The previous use of an anti-cough OTC for common cold was associated with higher odds of inappropriate selection of OTC (i.e., selecting anti-cough active ingredient to treat a health condition without cough). DFL was used by some young adults, and they selected different numbers of sections on the DFL to read. Reading Directions, Purpose and Uses, and Warnings were associated with higher odds of correctly answering the OTC use questions. Reading Active Ingredients was associated with lower odds of correctly answering the Indication question. Further, rational decision-making style (RDMS) score was positively correlated with reading information on the DFL and time spent processing information. Intuitive decision-making style (IDMS) score was negatively correlated with time spent processing information. RDMS score was negatively, and IDMS score was positively associated with the inappropriate use of OTC.
Conclusion: The inappropriate selection and use of OTC was prevalent, which emphasized the need to employ additional interventions to support young adults making OTC decisions. Insights into decision-making factors can guide the design of future intervention features and functions, ensuring they address the most commonly considered influences. RDMS prevented, and IDMS promoted the inappropriate use of OTC. Thus, future interventions should activate and support RDMS to prevent the inappropriate use of OTC among young adults. Previous experience of using anti-cough OTC medication might increase the risk of selecting the anti-cough OTC for the common cold without cough symptoms. Therefore, professional consultation and other interventions are essential to help young adults select appropriate OTC medications
Repurposing poultry effluents for irrigation in controlled environment agriculture
No full textRapid global population continues to drive increased demand for food production, placing significant pressure on water resources and nutrient availability. The poultry processing industry, which reflects this growth, produces approximately 901 billion liters of nutrient-rich wastewater globally each year. Although nutrients in poultry processing wastewater (PPW) holds significant potential for reuse in hydroponic systems, current industry practices treat PPW predominantly as waste. Concurrently, the agricultural sector is increasingly constrained by freshwater scarcity, rising fertilizer costs, and food safety concerns, necessitating innovative and circular resource-efficient solutions. However, there is a critical knowledge gap on the impacts of wastewater reuse such as: maintaining system performance in real-world, pilot-scale operations; crop productivity and nutrient utilization; and food safety. This dissertation introduces and validates “Poultryponics”, a novel bioponics system that integrates the biological treatment of PPW with hydroponic lettuce production, by assessing pilot-scale system performance, nutrient dynamics, plant yields, and food safety.
Microalgae enhance organics removal and nitrogen transformation in wastewater treatment via photosynthetic oxygenation to heterotrophic and autotrophic bacteria. The first objective therefore, assessed the impact of microalgae on treatment performance and fate of food pathogens during long-term (>220 days) continuous pilot-scale operation (~115 L d-1). The bioreactors achieved >80% soluble chemical oxygen demand (sCOD) removal but exhibited limited nitrification due to short hydraulic retention times (HRT), high organic loading, and oxygen limitation due to heterotrophic out competition. However, significant nitrification occurred in downstream hydroponic grow beds, driven by CO₂-supplemented pH modulation. UV disinfection showed approximately 40% and 30% reductions in total coliforms and aerobic plate counts respectively, with no Salmonella and Campylobacter detection in bioreactor effluents.
The second objective of this research evaluated the effect of treated PPW on lettuce yields and plant nutrient status. Lettuce cultivated on treated PPW exhibited 58% lower shoot biomass and deficiencies in K, Mg, Ca, and Cu compared to mineral fertilizer controls. However, lettuce growth inhibition with treated PPW was mitigated through pH control (pH=7.0) and nutrient supplementation (N, P, K and micronutrients). A nitrogen mass balance revealed that although nitrogen was not limiting for plant growth, nitrogen use efficiency (nitrogen assimilated by lettuce) ranged between 3.7 and 6.3% of input nitrogen, while 65.4 – 83.0% remained in effluents. This highlights the importance of balancing nitrogen supply with targeted nutrient supplementation to enhance lettuce growth on treated PPW.
The third objective of this study addressed a critical food safety concern by evaluating the system's response to high exogenous Salmonella influxes (3 and 5 log₁₀ CFU mL⁻¹) under simulated worst-case contamination scenarios and its implications for hydroponic lettuce. The bioreactors achieved 97.5 – 99.6% Salmonella removal, with no Salmonella detection in lettuce at the 3 log₁₀ CFU mL⁻¹ dosage. At the 5 log10 CFU mL -1 dosage, Salmonella removal in bioreactor effluent reduced to 68.4%, with Salmonella detection after UV treatment but not in grow beds or lettuce. Although these Salmonella dosages exceeded typical concentrations found in PPW, the results demonstrate the system’s capacity to manage extreme Salmonella contamination by maintaining non-detection in hydroponic lettuce.
To expand on the treatment performance observed in Poultryponics, the fourth objective involved a comprehensive microbial community analysis to determine the impact of bioreactor conditions (illumination, CO₂ supplementation, and pH control) on dominant microbial taxa involved in organics removal, nutrient transformation, plant growth promotion and food safety. The results demonstrated that Proteobacteria (80%). Illumination and CO₂ sparging promoted Desmodesmus (<45.8% of eukaryotes) in the algal bioreactors but had no impact on nitrification. Relative abundance of total nitrifying genera remained low in all bioreactors (<0.03%) but were increased in hydroponic grow beds (<4.31%) due to pH-modulating effects of CO2. Sulfuric acid-based pH control suppressed nitrifier and denitrifier abundance while enriching dissimilatory nitrate reduction to ammonium-associated taxa. Hydroponic grow beds enriched diverse plant growth-promoting bacteria with siderophore activity of approximately 0.6 ng L⁻¹ deferoxamine mesylate equivalence in the algal system.
The absence of nitrification in bioreactors presented a bottleneck due to incompatible pH requirements between nitrifiers and lettuce. Therefore, the last research objective was to establish a continuous multistage bioreactor configuration to promote upstream nitrification and to assess the impact of bioreactor HRT on treatment efficiency, nitrogen dynamics and microbial communities. The bioreactors achieved organics removal (80 – 96%) and complete nitrification (>70% of TN) at 72-hr HRT. However, nitrogen losses reached 43% of total nitrogen (TN) at 48-hr HRT, aided by denitrifier proliferation (Zoogloea and Hydrogenophaga) and the presence of carbon sources (VFAs, and amino acids).
This dissertation advances the practical implementation of bioponic systems for sustainable food production. It is the first body of work to demonstrate continuous long-term PPW treatment for safe hydroponic irrigation. The results provide a foundation for broader wastewater reuse applications across meat processing industries and field-scale agriculture within a circular bioeconomy
Online Learning Engagement, Resistance, and Motivation: Scottish Rite Members and the Master Craftsman Online College and Leadership Academy
Get PDFThis study examined how engagement, resistance, and motivation mediate the relationships between educational attainment, age, and course completion within the Master Craftsman Online College and Leadership Academy (MCOC), an educational platform offered
by the Scottish Rite of Freemasonry. Recognizing the MCOC’s role in promoting lifelong learning in a civic and fraternal context, the research aimed to identify key factors contributing to online course completion among adult male learners. A quantitative survey design was used with a final sample of Scottish Rite members (N = 224) aged 18 and older. Participants completed validated measures of learning engagement,
resistance, and motivation. The instrument combined the Learning Efficiency Inventory (LEI), and Motivated Strategies for Learning Questionnaire (MSLQ). Mediation analyses were conducted in SPSS and R to assess whether these constructs mediated the effects of educational attainment and age on course completion. Results indicated that motivation, but not engagement or resistance, indirectly mediated the relationship between educational attainment and course completion. Indirect significance was also indicated between age and motivation. These findings suggest that neither academic background nor age alone predicts success in non-traditional learning environments. Instead, motivation emerged as the most influential factor. Fraternal and civic educational programs should prioritize strategies that foster learner motivation to improve engagement and course completion outcomes
Leveraging intercropping system and genomics for breeding of allogamous crops towards sustainable agriculture
No full textAs agriculture transitions toward sustainable systems, breeding must prioritize not only yield but also persistence and ecological function. This study integrates whole-genome re-sequencing (WGR) and near-infrared spectroscopy (NIRS) phenotyping to inform breeding strategies in allogamous forage and cover crops within intercropping systems. We developed genomic resources for Trifolium incarnatum by resequencing 45 primary accessions at ~50x coverage, identifying 542,790 high-confidence SNPs. Additional replicates were sequenced at ~2x coverage, revealing approximately 2,411,468 high-confidence SNPs. The 2x and 50x datasets were aligned and annotated separately, providing high-quality SNP catalogs that can serve as a foundation for reduced-representation, low-cost genotyping platforms in the future. Population structure and genetic diversity analyses revealed partial regional clustering but have low genetic differentiation and a core allele set shared across improvement levels. Concurrently, we evaluated 26 Alfalfa (Medicago sativa) genotypes intercropped with Kernza® (Thinopyrum intermedium) across four U.S. locations. Forage quality traits, including crude protein (CP), lignin, ADF, NDF, and dNDF48 were assessed using NIRS and analyzed via mixed models. Although environmental effects dominated trait variation, consistent genetic signals in CP and lignin highlight potential for selection. Principal component analysis (PCA) revealed key trade-offs between nutritional (protein-related) and structural (fiber) traits. Understanding the interplay and trade-offs among these traits is essential for informed breeding decisions in alfalfa- Kernza® intercropping systems. Together, these findings establish both a genomic foundation and phenomics insight for the improvement of these agriculturally important legume species
The Impact of Social Media on Resilience in College Students
No full textThis quantitative study examined the relationship between social media usage motivations and psychological resilience among college students during emerging adulthood. Using a non-experimental survey design, 198 college students aged 19-25 completed the Connor-Davidson Resilience Scale (CD-RISC-25) and the Motives to Use Social Networking Sites Scale (MOTUS). Multiple regression analysis revealed that passive entertainment usage significantly predicted higher resilience scores (β = .206, p = .015), while passive social comparison approached a significant negative association (β = -.184, p = .054). Belonging motives demonstrated positive correlations with resilience, with active belonging with friends showing the strongest relationship (r = .315, p < .001). Comparative analyses indicated that both active and passive social media use positively predicted resilience outcomes, though active use showed stronger effects (R² = .064) compared to passive use (R² = .047). When examined together, active engagement emerged as the primary driver of the relationship. Exploratory analyses revealed significant gender differences, with women demonstrating higher resilience and greater engagement in social connection-focused behaviors. Students at 4-year institutions showed higher resilience than those at 2-year institutions. These findings suggest that the manner of social media engagement—particularly active participation involving social connection—may be more important for resilience development than simply the amount of use among college students
Configuration Changes in Kubernetes Configuration Scripts
Get PDFKubernetes has emerged as the dominant container orchestration platform, widely adopted for managing cloud-native applications. However, its dynamic configuration introduces complexities that can lead to security vulnerabilities, system failures, and operational inefficiencies. Understanding the patterns and implications of these configuration changes is crucial for improving system reliability, maintainability, and security. This thesis presents a large-scale empirical study of 28,675 Kubernetes-related commits to examine the nature of configuration changes. We categorize these changes into eight distinct types: Annotations, Corrective, Dependency Updates, Deployment Infrastructure, Documentation, Maintenance, Security and Compliance, and User Interface. We also analyze patterns in these categories by focusing on their frequency. Our study highlights that dependency updates and deployment infrastructure related changes are among the most frequent modifications, reflecting the critical need for up-to-date configurations, while other categories such as corrective, security and compliance show meaningful patterns in their frequency. Our classification sheds light on the nature of configuration-related changes in Kubernetes based container orchestration by characterizing the evolution of Kubernetes configuration changes by understanding the common trends in Kubernetes configuration. These findings offer a stepping stone for future research and practical tooling around configuration changes and provides actionable insights for Kubernetes practitioners, DevOps engineers
Taxonomy and Systematics of North American Monogenoidea Bychowsky, 1937
No full textParasitic flatworms in the class Monogenoidea Bychowsky, 1937 (Platyhelminthes) are demonstrable pathogens to wild and cultured fishes. The objective of this thesis was to diagnose (taxonomy and systematics) monogenoid infections in fishes of North America. The monogenoids described in this thesis were collected from a diverse group of hosts and environments including: a wild, invasive carp (Cypriniformes) from a major American river; a cultured, exotic tilapia (Cichliformes); a wild, endemic flyingfish (Exocoetidae) from the western Atlantic Ocean; and wild and captive rays (Myliobatiformes) in the western Atlantic Ocean and on exhibit in closed recirculating systems at a public aquarium respectively.
Few current-day parasitologists publish work on monogenoids from North America. As a product of this, many fishes in North America (exotic, invasive, or endemic) remain undocumented as hosts or host new, previously undiscovered monogenoids. Considering this, we surveyed a diversity of North American fishes (exotic, invasive, and endemic) for their monogenoids, particularly those unreported to host monogenoids (or any other parasite) in North America.
This thesis details the taxonomic identity and phylogenetic position of the monogenoids collected in each chapter. The sections in each chapter that do not pertain to the above-mentioned criteria discuss the significance of such infections or new morphological observations.
Chapter 1 reports the discovery of the first parasite infecting invasive silver carp in North America, Dactylogyrus cf. skrjabini (Dactylogyridae). Silver carp are Siberian xenocyprids (Cypriniformes) that have become invasive in North America after silver carp escaped aquaculture facilities in the 1970’s. Despite the focus on this fish from a management perspective, no parasite has ever been reported from silver carp in North America. Although we are the first to discover a parasite from silver carp in North America, many other silver carp parasites likely remain to be reported there. Chapter 2 reports the discovery of the first monogenoid infecting Nile tilapia (Cichliformes) in the U.S.A., Gyrodactylus cichlidarum Paperna, 1968 (Gyrodactylidae). Although this report comes from an aquaculture facility in Alabama, exotic Nile tilapia are introduced (with the potential to become invasive) in warmer climates in the U.S.A., and the presence of this parasite poses a risk to “spill over” to and cause pathology to related, endemic fishes that are sympatric to wild, exotic Nile tilapia. Chapter 3 reports the discovery of the second monogenoid infecting Nile tilapia in the U.S.A., Cichlidogyrus sclerosus Paperna & Thurston, 1969 (Dactylogyridae) and reviews the invasive range of C. sclerosus. This report comes from the same aquaculture facility as in chapter 2, and C. sclerosus presents similar risks to the monogenoid treated in chapter 2. Chapter 4 reports the discovery of a new species in the genus Axine (Axinidae) infecting Atlantic flyingfish (Beloniformes: Exocoetidae) from the western Atlantic Ocean. This species is distantly related to the monogenoids described in chapters 1–3 and represents the first species of Axine collected from a flyingfish in the western Atlantic Ocean. Through our morphological studies to identify the specimens of the new species we discovered and corrected ~250 years of literature that misinterpreted the morphology of the terminal female genitalia in Axine. Chapter 5 redescribes Benedeniella posterocolpa (Hargis, 1955) Yamaguti, 1963 (Capsalidae) and compares specimens of B. posterocolpa using morphology and nucleotides from cownose ray (type host), Brazilian cownose ray (newly reported host), and from giant manta (a charismatic ray kept in an aquarium with the type host) (all Myliobatiformes). We dismantle the presumption that B. posterocolpa is specific to the cownose ray. We also observe that the CO1 gene is variable between conspecific specimens of B. posterocolpa from the same individual host and is therefore ill advised to use as a species level barcode.
The reports included herein cover a diverse selection of hosts and environments and highlight the overlooked diversity of monogenoids that infect frequently encountered, exotic, invasive, or charismatic hosts in North America. North America is relatively well surveyed for monogenoids compared to other parts of the world. Therefore, the chapters below not only emphasize the abundance of remaining studies involving monogenoids infecting North American fishes but for the rest of the world too
Understanding the internal and external driving factors that impact specific gravity in Longleaf Pine through a spatial and temporal perspective
No full textSpecific gravity (SG, also called relative density) is a dimensionless quantity defined as the ratio of a substance's density (mass per unit volume) to the density of a given reference material. In forestry, wood SG is often measured as the ratio of the mass of wood of a unit volume to water at a given temperature of 4 °C. It is a critical factor in estimating tree carbon storage. This study aims to identify the key environmental variables influencing the SG of longleaf pine (Pinus palustris), examine their interactions, and explore regional variations in SG across its native southern range. Additionally, anthropogenic climate change altering weather patterns may drastically impact carbon storage because carbon storage heavily relies on available moisture. Additionally, past the ring count of 62, there is very little information on how carbon is stored in high ring count trees. Therefore, we must understand how ring count and climate, with their interactions, affect carbon storage from a temporal perspective. This study attempts to understand how different climate variables (PDSI, precipitation, temperature, and vapor pressure deficit) and soil (available water capacity, sand, silt, clay, and organic matter) impact wood specific gravity. Our main finding was a strong negative relationship between SG and ring count after year 62. We also found that both precipitation and very coarse particles had a positive relationship with SG. We found negative relationships between SG and spring precipitation, annual maximum temperature, coarse sand, and organic matter. Additionally, we found one positive relationship with rainfall during June through December. We also identified the interactions between spring precipitation, precipitation between June and December, annual maximum temperature, available water capacity, and sand. For the local coefficients in the GWR, we found that most of the spatial distribution aligned with our global coefficient. However, there were specific locations within each factor where the relationship with SG remained unexplained