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What Kids Have to Say About Math: Results from Focus Groups with Middle Schoolers
No full textMiddle school mathematics achievement remains a critical concern in Louisiana. Despite notable recent gains in recovery and signs of resilience, students continue to perform below national averages (ranking 38th in the country). To better understand the factors that support or hinder student success, this report presents findings from six student focus groups conducted in spring 2025 with 39 middle school students at two urban schools in Baton Rouge, Louisiana. The goal was to elevate students’ voices regarding their motivation, anxiety, classroom experiences, and ideas for improving math instruction. Overall, students expressed generally positive feelings toward math, and notably, a strong appreciation for their math teachers. Teachers were consistently identified as central to students’ motivation, particularly when they demonstrated enthusiasm, provided one-on-one support, and offered clear, timely feedback on how to improve. These positive relationships represent a key strength on which schools can build. At the same time, math anxiety—especially related to tests—emerged as a significant challenge, with students describing fear of making mistakes as a barrier to performing at their best.
The classroom environment also played an important role in shaping students’ experiences. Disruptive peer behavior, high noise levels, and poor disciplinary practices were frequently cited as obstacles to learning. Educational technology, particularly math software, was another common source of frustration due to perceived difficulty, lack of clarity, limited feedback, and technical issues. In fact, over-reliance on technology was mentioned by numerous students as a barrier to learning math. Students expressed a preference for more hands-on, interactive, and teacher-guided learning experiences, which is notable given the perception that younger generations are tech-oriented.
Across discussions, the most consistently mentioned motivator for students was relevance. Students repeatedly emphasized the importance of understanding why math matters—whether for real-life applications, future careers, future education, or personal goals. Other key motivators included receiving both positive (what they were doing right) and corrective (how they could do even better) feedback, having opportunities and encouragement to persist through challenges, and being given meaningful choices in how they learn or demonstrate understanding. In contrast, demotivators included overly complex material, excessive workload across classes, lack of review, and learning environments that felt punitive or unsafe. Students strongly endorsed practical, low-cost interventions to improve motivation and reduce anxiety. These included creating classrooms where mistakes are normalized, offering grade recovery options, clearly explaining the purpose of lessons, providing structured goals, and increasing student agency through choice and flexibility. Together, these findings suggest that improving middle school math outcomes requires attention not only to curriculum and instruction, but also to students’ emotional experiences, sense of agency, and classroom climate
Bovine Anaplasmosis in Louisiana: Management Practices that Contribute to Herd Infection and Prevalence of Anaplasma Marginale in Louisiana Cow-Calf Herds
No full textBovine anaplasmosis is an infectious, non-contagious, hemolytic disease of cattle that is caused by the organism Anaplasma marginale (A. marginale). Ticks (Dermacentor variabilis and Dermacentor andersoni) are the primary biological vectors, and mechanical vectors include biting insects or by blood-contaminated fomites including needles, ear tagging, tattooing, dehorning, and castration equipment. Therefore, the objectives of this study were to 1) evaluate management practices that may contribute to bovine anaplasmosis herd infection; 2) estimate the prevalence of bovine anaplasmosis in Louisiana cow-calf herds; and 3) validate the Pluslife Anaplasma/Ehrlichia Nucleic Acid Test Kit for use in cattle. Louisiana cattle producers (n = 62) completed an online Qualtrics survey that included questions on producer demographics, herd demographics, health management, and biosecurity approved by the Louisiana State University Agricultural Center IRB (IRBAG-24-0117). Survey questions were used to infer how management practices relate to bovine anaplasmosis infection status. Chi-square tests were used to determine associations between several management practices and anaplasmosis diagnosis. Factors found to be significant or suggestive were included in a logistic binary regression model to test for significance. According to survey results, neighboring herd diagnosis (OR = 10.839, 95% CI: 2.041-57.566, p = 0.005), use of tattoos (OR = 5.124, 95% CI = 0.974-26.961, p = 0.054), and calving season length (OR = 28.00, 95% CI = 1.35-580.59, p = 0.031) were all predictors of anaplasmosis status. Blood samples were collected from 256 mature cows from 26 herds across five regions between March and September 2025 to estimate disease prevalence. Based on cELISA testing, the herd-level prevalence was 57.7%, and the individual cow prevalence was 19.1%. A multilevel binary logistic regression was conducted to assess whether the odds of a positive test result varied across the five regions. Region was not a significant predictor of anaplasmosis diagnosis. Sixteen cELISA positive and sixteen cELISA negative blood samples were used in an attempt to validate the Pluslife Anaplasma/Ehrlichia Nucleic Acid Test Kit. The kit did not yield interpretable results under the conditions applied. As a result, no statistical analysis could be conducted to evaluate its potential role as a diagnostic test for bovine anaplasmosis
2024-2025 ECEI Annual Report
No full texthttps://repository.lsu.edu/ecei_annual_reports/1002/thumbnail.jp
Cancer Screening Resilience During The COVID-19 Pandemic
No full textTo help control the spread of coronavirus disease 2019 (COVID-19), health care organizations suspended nonessential medical procedures, including preventive cancer screening, in early 2020, with effects on cancer screening services lasting beyond the original restrictions. Many individuals canceled or postponed cancer screening, potentially delaying cancer diagnosis, and healthcare providers had differing policies, procedures, and priorities to address the pandemic, as well as varying levels of access to routine care, such as cancer screening. In contrast to earlier research on COVID-19 cancer screening deficits, this research quantified declines at the Medicare Fee-for-Service provider level and constructed models to predict the counterfactual level of screening for 2020 and 2021. The resilience of providers in four cancer screening lines- cervical, colorectal lab, colorectal procedure, and prostate cancer screenings- was determined, and it was found that 2,626 of 18,808 providers (14%) were resilient during both 2020 and 2021. By year, 4,921 (26%) were resilient in either 2020 (963) or 2021 (3,958), and 11,261 (60%) were not resilient in either year.
In the examination of explainable variation in a county-level model of the ratio of 2020-2021 observed beneficiaries to predicted beneficiaries (Resilient Beneficiary Index), characteristics aligned with providers’ practices were the most contributory domain, accounting for 48%. The next most contributory domains were Social Determinants of Health (SDOH), at 30%, COVID restrictive measures at 18%, and county-level demographics at 4%, with a significant portion of the variability yet to be explained. Further research may refine and extend these findings
Tolerating Threat: Why Americans Disagree on What and Who Deserve First Amendment Protections
No full textThis dissertation explores how perceptions of out-groups and potential threats shape tolerance for free expression, challenging assumptions about the influence of individual characteristics. While previous research has often attributed consistent effects to factors like education, income, age, partisanship, race, and gender, my findings reveal that these relationships are created by context. Utilizing four datasets—three secondary and one experimental—I illustrate that most characteristics only exhibit significant effects in specific contexts controlling for out-group identity and perceptions of violence. This finding not only suggests a need to move beyond examining individual characteristic effects toward understanding how contexts shape their influence on tolerance for free expression, but illustrates a framework to understand the conditions that make a characteristic significantly affect support for out-group free expression in a specific context. Ultimately this finding contributes to the scholarship by providing a deeper understanding of how context creates significance for each characteristic rather than a characteristic being intimately related with support out-group free expression
Quantifying Uncertainty In Landscape Evolution And Provenance Analysis: Insights From Statistical And Numerical Modelling
No full textLandscape evolution models (LEMs) and detrital zircon provenance are widely used to investigate Earth surface processes, yet both face challenges related to quantifying model behavior and interpreting sedimentary signals under realistic, heterogeneous conditions. This thesis addresses these challenges through analysis and case studies that develop and apply new approaches for analyzing landscape dynamics and assessing uncertainties in sediment provenance.
Chapter 1 introduces a quantitative framework for evaluating LEM outputs using Shannon Entropy, Moran’s I, and Geary’s C. Applied to simulations with steady uplift, periodic uplift, spatially variable uplift, and a timeseries of DEMs, these metrics capture spatial organization and information content within and across model runs. This approach enables systematic detection of divergence, variability, and spatial coherence in model behavior, offering a flexible toolset for improving comparisons among simulations and for analyzing any matrix-based topographic dataset.
Chapter 2 examines key assumptions underlying detrital zircon provenance analysis, specifically the uniformity of erosion rates, zircon fertility, and zircon grain-size distributions within source areas. Using suites of statistical simulations, the influence of parameter variations on provenance age distributions was evaluated, along with the extent to which models weighted by area, zircon mass, or zircon abundance diverge. Results show that population complexity, parameter variation, and sample size jointly control the distinctiveness of provenance signals, with larger sample sizes reducing variance and parameter differences generally producing subtle effects when realistic source populations are used.
Chapter 3 links surface processes directly to detrital zircon signals by integrating landscape evolution modeling with zircon transport and sampling. Using Landlab and coupled erosion–sediment transport components, the influence of variable rock erodibility, layered stratigraphy, zircon fertility, and zircon grain size on the time-dependent provenance record is evaluated. The experiments demonstrate that surface processes imprint measurable and sometimes systematic biases on detrital zircon distributions, and that zircon-specific properties can either amplify or moderate these effects.
These studies examine quantitative methods for analyzing model outputs and investigate how landscape dynamics and zircon characteristics shape sedimentary signals, highlighting the importance of moving beyond simplifying assumptions and embracing spatial variability to better understand how Earth’s surface processes are recorded in both models and provenance
Electrocatalytic Reduction of Nitrite using Small Organometallic Complexes with Nitrogen-rich Ligands: Mechanistic and Ion Non-innocence Insights
No full textDue to the increased demand in food, modern agriculture has caused the overuse of fertilizers. This overfertilization can alter many global processes including the nitrogen cycle. Of the contaminants nitrogen oxyanions are of particular interest. Nitrite in water is fatal to fish, can cause eutrophication, and can be harmful to human health. Electrocatalysis is a possible way to minimize nitrite in water. There are two different reaction pathways for the reduction of nitrite in water, the first follows the denitrification pathway that generates gaseous products including NO, N2O, and N2. The second pathway produces other products including NH2OH and NH3/NH4+. Of the reports previously, copper complexes have been used for the reduction of nitrite following the denitrification pathway and cobalt complexes have been used to follow the second pathway. The work presented in this dissertation focuses on the synthesis, characterization, and electrochemistry of both copper and cobalt complexes with nitrogen-rich ligands. Further, one copper complex is studied in more detail to understand the fundamental mechanism behind the electrocatalytic reduction of nitrite
Trophic Relationships Among Invasive Silver Carp (Hypophthalmichthys molitrix) and Native Fishes in the Lower Mississippi Alluvial Valley
No full textSince their introduction in the 1970s, invasive Silver Carp (Hypophthalmichthys molitrix) have had significant impacts on aquatic ecosystems throughout the Mississippi River watershed. Anthropogenic factors such as modifications to stream connectivity and climate change-driven shifts in hydrology and temperature have facilitated rapid expansion of these highly invasive fish. Despite their spread in Louisiana waterbodies, trophic effects of Silver Carp on native species and food web dynamics in the lower Mississippi River (LMR) remain poorly understood. As efficient planktivores, Silver Carp directly compete with native planktivorous species, potentially altering abundance and composition of forage available to both native planktivores and piscivores. Additionally, their grazing activities can disrupt nutrient cycling, water clarity, and primary production, leading to ecosystem imbalances in sensitive habitats. In chapter 1, I used stable isotopes from fish collected in fall 2022 through fall 2024 to investigate trophic relationships among Silver Carp and several native fishes commonly found throughout southeastern watersheds. Results indicated significant trophic overlap between Silver Carp and Bigmouth Buffalo (Ictiobus cyprinellus), Gizzard Shad (Dorosoma cepedianum), and Striped Mullet (Mugil cephalus). In chapter 2, I compared body condition of Silver Carp from inland and coastal Louisiana with previous data from studies conducted in the upper and middle Mississippi River regions. Results showed Silver Carp were significantly longer than conspecifics from other regions, suggesting increased consumption and/or feeding efficiency in these subtropical systems. These results underscore the urgent need to evaluate their trophic interactions, food web impacts, and broader ecological impacts on native aquatic communities. Developing effective management strategies is crucial to mitigating ecological disruptions caused by Silver Carp and maintaining biodiversity and ecosystem health in southern river drainages
Robust Adaptive Control and Disturbance String Stability for Heterogeneous Uncertain Nonlinear Vehicle Platoons
No full textThis dissertation investigates cooperative control of heterogeneous vehicle platoons, in cluding both autonomous electric vehicles (EVs) and gasoline vehicles (GVs), over both predecessor-following (PF) and bidirectional (BD) topologies. The platoon systems are in herently nonlinear and subject to unknown and uncertain parameters due to wear-tear, ageing, varying road conditions, and exogenous disturbances. To address these challenges, we propose two scalable distributed robust adaptive control laws that explicitly cope with parameter uncertainties and model nonlinearities. Specifically, a direct distributed adaptive control law based on passivity approach is proposed to solve the DSS problem for EV pla toons, and an indirect distributed adaptive control law based on linear matrix inequalities (LMIs) is developed to tackle the DSS problem for GV platoons. These two distributed adap tive control laws are robust, achieving not only velocity synchronization and safe inter-vehicle distances (IVDs) in the absence of disturbances, but also ensuring disturbance string stability (DSS) in the presence of the worst-case energy-bounded disturbances without known bounds. The results are global, independent of initial conditions, and robust to parameter uncertain ties and exogenous disturbances, which stand in sharp contrast to the existing results in the literature. Simulation studies confirm the effectiveness of the proposed distributed robust adaptive control laws for platoon control of heterogeneous uncertain nonlinear EVs and GVs over both PF and BD topologies. The results demonstrate superior performance compared to the existing methods, validating the robustness, scalability, and practical viability of the proposed approaches for cooperative vehicle platoon control
DECOUPLING OF REPRODUCTION AND LIFESPAN TRADE-OFF IN CAENORHABDITIS ELEGANS THROUGH MICROBIAL PROGRAMMING
No full textThe microbiome is increasingly recognized as a major regulator of host physiology. Using the Caenorhabditis elegans model, we investigated how natural commensal bacteria modulate host reproduction and lifespan through internal egg hatching, a phenotype in which retained embryos hatch within the maternal body. Screening strains from the CeMbio collection identified four focal strains Ochrobactrum BH3, Lelliottia JUb66, Pantoea BIGb0393, and Enterobacter CEent1 that significantly increased internal egg hatching during the late reproductive period. This contrasts with pathogenic bacteria, which induce early-onset internal egg hatching. Across the focal strains, worms exhibited reduced total brood size but an expanded reproductive window relative to worms grown on the standard Escherichia coli OP50. To determine whether these microbial effects act through host insulin/IGF-1 signaling (IIS), internal egg hatching was quantified in IIS mutants. In BH3 this phenotype likely acts via DAF-16/FOXO. In JUb66. BIGb0393, and CEent1, the phenotype likely acts independently of DAF-16. Lifespan analyses further demonstrated bacterial specificity, BH3 uniquely extended host lifespan, whereas the remaining three strains reduced lifespan relative to OP50. Together, these results show that natural commensal bacteria can reshape host reproductive timing, internal hatching dynamics, and longevity. This work underscores the microbiome as a potent driver of life-history variation in C. elegans