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A Profession Worth Fighting for: What’s Getting in the Way of What I’m Purposed for? An Autoethnography of a Black Teacher’s Lived Experience Educating in Georgia
No full textThe purpose of this qualitative autoethnography is to explore the relationship between the teacher evaluation process and the underlying attrition factors of Black teachers in a K–12 public school setting. The problem that this seeks to address is the high attrition factors of Black teachers in a K–12 setting in the United States, precisely, how the modern teacher evaluation system lacks the holistic value of teacher identity concerning race and contributes to attrition rates. The researcher used self-narrative, reflexivity, and dialogue to put the self at the center of cultural analysis and document a narrative that is otherwise absent in the mainstream research literature. Exploring the relationship between a Black teacher’s lived experiences with evaluation and her willingness to stay in the profession occurred via two research questions: (1) How did one Black teacher experience and navigate the formal teacher evaluation process? (2) How did the formal teacher evaluation process affect one Black teacher, specifically the desire/willingness to remain in the teaching profession? Black liberation theory contributed substantially to this study since its collaboration with critical race theory allowed the examination of the phenomenon to illuminate the punitive nature of the teacher evaluation process. The findings highlight the paramount importance of integrating critical race theory into educational explorations for better comprehension of the intersectional experiences of Black female educators when undertaking the prescribed evaluation process. The findings underscore the need to explore how race, gender, and other identity factors intersect to shape teachers' experiences and outcomes. Therefore, this study amplifies the voices and experiences of Black teachers, aspires to create more inclusive and supportive educational environments, and empowers Black teacher and teachers of color to fulfill their calling and nurture holistic expressions among all stakeholder
Three Chapters In Applied Economics
Get PDFThis dissertation comprises three chapters that address significant issues in applied
economics, focusing on energy, agricultural trade, and environmental conservation.
The first chapter, "The Impact of Small Refinery Exemptions on Renewable Fuel Market
Factors in the United States" investigates the effects of regulatory exemptions on the renewable
fuel industry. Small refinery exemptions (SREs) have been a contentious topic, as they allow
certain refineries to bypass Renewable Fuel Standard (RFS) obligations. This chapter employs
econometric models to analyze the influence of SREs on biofuel production, prices, and
agricultural feedstock markets.
The second chapter, "China’s Changing Demand for U.S. Agricultural Commodities:
Structural Change in China’s Import Demand for Meat, Grains, and Oilseed Crops," explores the
evolving trade dynamics between China and the United States. With China's rapid economic
growth and shifting dietary preferences, there has been a notable increase in its demand for
imported agricultural commodities. This chapter utilizes a structural change framework to assess
how China's import patterns for meat, grains, and oilseeds have transformed in recent times.
The third chapter, "Mitigating Climate Change with the Conservation Reserve Program
(CRP): The Role of Carbon Credits and CRP Redesign," examines the potential of the CRP in
contributing to climate change mitigation. This chapter evaluates the effectiveness of CRP in
sequestering carbon and proposes redesigns to enhance its climate benefits. The study also
explores the integration of carbon credits into the CRP, providing a market-based mechanism to
incentivize greater participation and maximize environmental gain
Investigation of Ribosomal Dynamics in E.coli Using Single-molecule FRET
Get PDFTranslation, the last step of gene expression, highly determines an organism’s normal function. Ribosomes are molecular motors that synthesize proteins from mRNA using amino acids carried by tRNAs. A ribosome’s mobility on mRNA is provided by conformational changes such as 30S subunit head movements, L1 stalk movements, and intersubunit rotations. Intersubunit rotations are the counterclockwise and clockwise rotations that happen between the large and small ribosomal subunits. Major steps of translation such as ribosome assembly, peptidyl transfer, and translocation are promoted by intersubunit rotations. However, ribosome rotations are transient, making these movements difficult to capture. Here, high-speed single-molecule microscopy was used to follow the translational intersubunit rotations in real time. The 30S subunit was labeled with a fluorescent donor dye (Cy3B) on helix 44 and the 50S subunit was labeled with an acceptor dye (Cy5) on helix 101. The FRET changes between two labeled subunits were used to study the translation mechanism by monitoring the ribosome’s rotations. First, mRNA initiation was studied using fluorescently labeled leaderless mRNA which demonstrated that leaderless mRNA could initiate through two pathways. Next, the antibiotics viomycin, neomycin, and spectinomycin were added to perturb translation by disrupting ribosome movements. This further revealed the mechanism of initiation. Finally, ribosomes were found to spontaneously exchange between three different rotational conformations in the pre-translocation state. These results suggest that ribosome rotations are highly involved with translation. Understanding translational mechanisms will contribute to understanding bacterial gene expression, stress adaptation, and the evolution of protein synthesis
Elementary Teachers’ Perceptions of Teacher-Student Relationships and Associations with Project Lead the Way
Get PDFThis study is motivated by the primary research question, “Is Project Lead the Way (PLTW) instruction associated with elementary teachers' perceptions of their relationships with students and how?” Previous research has attempted to identify predictors that would positively impact teacher-student relationships (TSRs), however few studies have sought to understand associations between TSRs and instructional styles. The purpose of this mixed methods sequential explanatory study was to explore associations between the teacher participants’ perceptions of their TSRs and their use of the PLTW curriculum. The two-phase investigation obtained quantitative results from a 19-item online survey of 83 elementary teachers in a public school district and then followed up with interviews of nine purposefully selected individuals. A mixed regression analysis of the quantitative data from the present study found that teachers from the PLTW-trained group had significantly lower STRS-SF scores (B = -2.713, β = -.287, t = -2.625, p < .05). The equation explained about 14 percent of the variance in STRS-SF scores (R^2 = .139, Adj. R^2 = .095). Two meta-inferences were developed from four themes that emerged from a line-by-line analysis of the qualitative interview data. Overall, this study found that the quantitative and qualitative strands of data combined to show that significantly lower STRS-SF scores within the PLTW group related to a supplanting of the teacher’s role as facilitator and a limitation of opportunities for student-centered instruction
Evaluation of Broiler Litter as a Nitrogen Source for Corn and Cotton Production in Alabama
No full textThis dissertation yielded critical findings on the agronomic use of broiler chicken (Gallus gallus domesticus) litter, a byproduct of the poultry industry, for corn (Zea Mays L.) and cotton (Gossypium hirsutum L.) production in Alabama. Much of the poultry industry is concentrated in the southeastern United States with Alabama ranking second nationwide in broiler production. Consequently, broiler litter is produced in large quantities (an estimated 2 million tons) in the region. Broiler litter is an excellent source of organic matter and contains all essential plant nutrients including nitrogen (N). Utilization of broiler litter as a soil amendment and nutrient-rich fertilizer for row crop production in the southeastern United States is increasing. However, there are no fertilizer N management guidelines for corn and cotton fields that receive broiler litter in Alabama.
The first study investigated the effects of fertilizer N rate on broiler litter–fertilized corn grain yield and nutrient composition. Field experiments were conducted in 2020 and 2021 over three diverse environments (Wiregrass, Tennessee Valley, and Gulf Coast Research and Extension Centers) across Alabama to determine the agronomic optimum nitrogen rate (AONR) for broiler-litter–fertilized corn with five side dress fertilizer N rates (0, 84, 140, 196, and 252 kg N ha−1). Broiler litter (4.48 Mg ha−1 equivalent to 2-ton acre−1) was applied to the study sites before planting each year. The results revealed that the AONRs for grain yield varied by location and year from 114 to 223 kg N ha−1. With the preplant application of broiler litter at a rate of 4.5 Mg ha−1 yr−1, corn producers may require 0.013 to 0.027 kg of fertilizer N per kg of grain yield ha−1. Grain N concentration increased with increasing fertilizer N rate; however, the weak to nonexistent correlation between fertilizer N and other grain nutrient elements suggests that raising the fertilizer N rate does not necessarily lead to higher nutrient levels in corn grain. Overall, these findings are useful for developing N management guidelines for corn fertilized with broiler litter.
The second study evaluated the agronomic response of broiler litter–fertilized cotton to supplemental fertilizer N rate. A five-site-year field study was conducted at Wiregrass and Tennessee Valley Research and Extension Centers from 2021 to 2023 to assess the effects of fertilizer N application (0, 28, 50, 62, 78, and 95 kg ha−1) on broiler litter–fertilized cotton lint yield, above-ground biomass, tissue nutrient concentrations, nutrient uptake, lint turnout, fiber quality, and soil test nutrient changes. Broiler litter was applied at a rate of 4.5 Mg ha−1 yr−1 before planting. The results showed that the lint yield of cotton receiving only broiler litter (i.e., zero fertilizer N treatment) equaled that of the treatments receiving a combination of broiler litter and fertilizer N at relatively low yield potential (968 to 1472 kg ha−1). However, a positive crop response to fertilizer N (up to 50 kg ha−1) was observed at high yield potential (1990 to 2544 kg ha−1). With a few exceptions, fertilizer N had no significant effect on above-ground biomass, tissue nutrient concentrations, lint turnout, or fiber quality measurements in any growing season. Although these results suggest that broiler litter can be used as a primary N fertilizer for optimal cotton production, elevated concentrations of P, K, and Mg (by 14, 90, and 18%, respectively) in surface soil (0–15 cm depth) were observed at the end of study. Therefore, continued land application of broiler litter may be an environmental concern and should be avoided when surface soil test nutrients exceed critical levels.
Complementing the above studies, a third study investigated the effects of broiler litter total cleanout frequency (in other words, the age of broiler litter) on corn grain yield, biomass accumulation, nutrient uptake, and grain nutrient composition. Broiler producers periodically clean their broiler houses to the ground level (i.e., total cleanout) to improve flock health and prevent disease outbreaks. However, the frequency of total cleanout practiced on a broiler farm can impact N content of broiler litter and subsequent N release to crops. A 3-yr field study was established on a Decatur silt loam (Belle Mina, AL) and Malbis sandy clay loam soil (Fairhope, AL) to examine three broiler litter total cleanout frequency periods (2yr). The investigation revealed no significant differences in corn growth and grain yield with respect to total cleanout frequency of broiler litter, suggesting that this management practice may not affect the fertilizer value of broiler litter. Information on the crop response to age of broiler litter is important for producers whether utilizing their in-house broiler litter or buying from commercial markets and could help guide producer’s decision on broiler litter choice.
In addition to these field plot studies, the final study explored the impact of extreme rainfall (any heavy or greater-than-normal rainfall with distinct deviation from the mean rainfall level and a low occurrence probability) on runoff, infiltration, total suspended solids (TSS), and nutrient [dissolved reactive phosphorus (DRP), total phosphorus (TP), particulate phosphorus (PP), ammonium N, and nitrate N] losses on three land use systems (pasture, conventional and conservation tillage cropping systems). Extreme rainfall events are becoming more common in many regions of United States, including the southeast U.S. Agricultural systems that prioritize surface residue cover through crop rotation or conservation tillage may be more resilient to climate change-induced rainfall intensification. We conducted a rainfall simulation experiment in which we collected intact soil blocks from cropping systems managed under conventional tillage (CVT) and conservation tillage (CST) as well as pasture fields on silt loam to silty clay loam (Abernathy-Emory, Dewey, and Etowah soil series) and sand to loamy sand (Lucy and Dothan soil series) soils. Two one-acre-inch (0.0245 m) rainfalls were applied 24-hr apart to simulate the intensity of a 10 and 25-yr storm in a 5 min duration. Pasture fields showed little to no runoff; however, they had the highest losses of DRP, TP, and inorganic N (ammonium N + nitrate N) through leaching. The CVT and CST cropping systems had similar runoff volume and associated TSS, TP, and PP losses in both soil types regardless of rainfall intensity. Yet, the CST cropping system showed greatest runoff losses of DRP and inorganic N in silty clay loam soil, likely due to nutrient buildup at the soil surface. Overall, these results suggest that leaching is the dominant loss pathway for P and N in pasture systems and that surface residue cover may protect against runoff losses during extreme rainfalls
Experiential Learning vs Traditional Classroom Lecture for Lean Manufacturing Education
Get PDFThis study involved Lean Manufacturing (LM) education conducted within a Simulated Factory (SF). Experiential Learning Theory was used to design the training. The purpose of this study was to validate the efficacy of the Experiential Learning (EL) method, with a focus on the Lean Manufacturing (LM) sub-topic of Just-In-Time (JIT). While there are many examples of Experiential Learning (EL) for Lean Manufacturing (LM) education in a Simulated Factory (SF) cited in this study, efficacy validation has relied primarily on qualitative data. Building a Simulated Factory (SF) requires significant investment; therefore, quantitative research to demonstrate the superior efficacy of this approach will be helpful to Lean Manufacturing (LM) educators in justifying investment.
Lean Manufacturing (LM) is the 3rd generation of Manufacturing after the Job Shop and Henry Ford's Mass Production System (Black & Phillips, 2013). Lean was coined in the landmark book; “The Machine That Changed the World” to describe the Toyota Production System (Womack et al., 1990, p. 13). The "Father of the Toyota Production System" was Taiichi Ohno, Toyota's Executive Vice President from 1975 to 1978. Ohno spent many years perfecting the Lean system from shop floor supervisor to executive vice president.
Lean Manufacturing (LM) is challenging to teach in a traditional classroom environment, which has led to many Simulated Factories (SF) being set up in universities. Manufacturing companies train their employees within their operations. Hands-on experience in a realistic shop floor environment is the most suitable way to internalize lean concepts (Abele et al., 2010).
The Lean Manufacturing (LM) sub-topic of Just-In-Time (JIT) is particularly difficult to comprehend in a lecture environment. Taiichi Ohno sent senior managers to supplier locations to teach and implement (JIT) methods. Past teaching attempts failed, and Ohno concluded that Just-In-Time (JIT) must be taught while being implemented at supplier locations.
Jim Womack, the author of “The Machine That Changed the World and “Lean Thinking,” stated in the forward of the book “Learning to See” by Rother and Shook that step 4 of the step-by-step lean transformation process described in Chapter 11 of Lean Thinking is the most important step in a company's lean transformation journey and the step most often skipped in the 5-step process. Step 4 involves mapping the entire value stream for all product families.
“Learning to See” is a seminal Lean Manufacturing book explaining the Value Stream Mapping
Process (Rother et al., 2003).
Value Stream Mapping (VSM) is a Just-In-Time (JIT) tool used to uncover waste within a manufacturing system. Trainees understand the importance of Value Stream Mapping (VSM) on an intellectual level; however, implementation requires experience for the deep understanding needed for use. This study followed Kolb's experiential learning cycle (Kolb, 1984) to design Just-In-Time (JIT) training within a Simulated Factory (SF) to improve the efficacy of Just-In-Time (JIT) instruction.
Four tests were conducted to compare Pre- and Post-test survey results for students with Classroom Lectures and Experiential Learning in a Simulated Factor (CLELSF) vs. students with Classroom Lectures (CL) only. The data indicated improved efficacy for those students engaged in experiential learning within the lab. Distance students without the benefit of the lab experience performed at the same level, likely due to their Adult Learner status.
Of the four sub-topic areas of Lean Manufacturing tested, Just-In-Time (JIT) knowledge improved at a greater rate when compared to Jidoka, and Standardization and overall Lean Manufacturing knowledge
Timely Inference over Networks
Get PDFNext-generation communications (Next-G), such as 6G, are expected to support emerging networked intelligent systems, including autonomous driving, factory automation, digital twin technology, unmanned aerial vehicle (UAV) navigation, and extended reality. Timely inference is crucial for these networked intelligent systems. In this dissertation, we investigate a remote inference system, where a trained neural network is used to infer time-varying targets (e.g., the locations of vehicles and pedestrians) based on features (e.g., video frames) observed at a sensing node (e.g., a camera). The inference error is determined by (i) the timeliness and (ii) the sequence length of the features, where we use the Age of Information (AoI) as a metric for timeliness. In the first part of the dissertation, we discuss how to evaluate the importance of timely information in remote inference and the monotonicity of information aging. One might expect that the performance of a remote inference system degrades monotonically as the feature becomes stale. Using a new information-theoretic analysis, we show that this is true if the feature and target data sequence can be closely approximated as a Markov chain; it is not true if the data sequence is far from Markovian. Hence, the inference error is a function of the AoI, where the function could be non-monotonic. In addition, a longer feature can typically provide better inference performance, but it often requires more channel resources for sending the feature. In the second part of the dissertation, we study the transmission scheduling problem that optimizes timeliness and feature sequence length to minimize inference error. We introduce a new "selection-from-buffer" medium access model for status updating and minimize inference errors for both Markovian and non-Markovian data. For single-source and single-channel remote inference networks, we obtain optimal scheduling policies for both the cases of time-invariant and time-variant feature lengths. In multi-sources and multi-channel remote inference networks, the selection-from-buffer scheduling problem is a multi-action restless multi-arm bandit problem. For this setting, we design new scheduling policies by utilizing the Whittle index and duality-based gain index. The new scheduling policies are proven to be asymptotically optimal. Data-driven evaluations show that our policies can reduce inference errors by up to 10,000 times
Fungal endophyte presence in relation to various nutrient regimes applied to Gossypium hirsutum
No full textProper nutrient conditions are necessary for optimal growth and yield of Gossypium hirsutum. This can be achieved through fertilizer application, but plants may also be assisted by fungal endophytes, potentially beneficial microorganisms in the tissue of plants. In the Southeastern United States, Cotton leafroll dwarf virus (CLRDV) is a concern for cotton producers; however, a potential management strategy is the use of fungal endophytes. Experiments in 2022 and 2023 evaluated culturable fungal endophytes from the foliage of G. hirsutum growing in various nutrient regimes at the Cullars Rotation (Auburn, AL), where the soil fertility treatments have been in place for over 100 years. The isolated genera included Alternaria, Cladosporium, Colletotrichum, Diaporthe, Fusarium, Phoma, and Stemphylium. In 2022, the relative abundance of Colletotrichum truncatum was around 50% in the no potassium regime, Diaporthe sp. abundance was over 50%, in the no phosphorous regime, and Alternaria abundance was around 25% in all sampled regimes except the no potassium regime. The only endophytic species isolated from the no potassium regime in 2023 were Stemphylium vesicarium and S. solani. Relative to endophyte diversity, a significant difference (P ≤ 0.05) was observed in 2023 between the no potassium regime and all other sampled regimes. Incidence of CLRDV was determined in the Fall of 2023 to observe whether infection differs among G. hirsutum treated with various nutrient regimes or if it relates to endophytic presence. The results were insufficient to further explore a relationship between CLRDV, endophytes, and nutrients. The fungal endophyte microbiome in G. hirsutum leaf tissue was analyzed in 2023. In relation to fungal endophyte diversity, the no potassium regime was significantly different (P ≤ 0.05) from all other sampled regimes. The relative abundance of Stemphylium was over 50% of the population in the no potassium regime. Diaporthe abundance was high, greater than 50% of the community composition in the no phosphorous regime. Stemphylium spp. and Colletotrichum truncatum were identified as indicator species, signifying differences in the community based on the applied nutrient regime. The findings of this research indicate that fungal endophyte presence may be impacted by nutrient regimes applied to G. hirsutum
Male Wild Turkey Fertility and Disease Prevalence in Alabama
Get PDFWild turkeys (Meleagris gallopavo) are the second most pursued game species in the United States, and the spring hunting season attracts tens of thousands of hunters afield annually in Alabama. Despite their popularity as a game species and their importance among some communities, concern for their population has increased over the past 10–20 years. During this time, multiple datasets have grown to suggest declining or stabilizing trends in hunter-harvest and annual population recruitment. Some managers and stakeholders have speculated about the role of hunter-harvest in annual reproduction and have questioned if early and intense male removal may have a role. Secondly, changes in the prevalence of known diseases or the introduction of new ones have remained unknown in Alabama for many years. Thus, to address these knowledge gaps, we worked with spring wild turkey hunters to collect samples and paired observational surveys. We found that adult male wild turkeys are more fertile than subadults and that decoy use by hunters selects for more fertile adult males. However, the low decoy-aided harvest rate (3%) we observed does not likely negatively lead to genetic drift or affect population recruitment. Related to disease, we detected Histomonas meleagridis, the protozoan that causes histomonosis, in 0.7% (3/434) of our sample. We detected lymphoproliferative disease virus in 72.7% (609/838) of tested males, and a negative relationship between a county’s prevalence and proportion of mixed forest. These results contradict some earlier studies and emphasize how many questions about diseases’ impacts on wild turkey populations remain unanswered
There’s no place like home: University campus-student interaction to promote sense of belonging among first year international students
Get PDFAcclimating to a new environment can take a mental and emotional toll on anybody; compounding that change in an environment with a cultural change can intensify the toll. This study explores the initial perceptions and experiences of international students during their first semester on an American college campus. Specifically, this study explores the importance of spaces designed for social engagement and the impact of the design of those spaces on international student’s transition to the college campus. The purpose of this study is to gain understanding of firsthand experiences within these spaces on a Southeastern college campus, with regards to social connectedness, sense of community, and place attachment. Increasing the knowledge of how the design of campus influences these culturally diverse students can lead to more inclusive and well-planned design for all students. Findings from this research support thoughtful and purposeful design practices to facilitate quality connection and engagement among students on college campus. Understanding of the ways in which a space communicates with an occupant to inform perceptions of belonging and inclusion can lead to high quality experiences, and increased place attachment