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Going beyond the average treatment effect: estimating the diverse impacts of a home visiting intervention on infant breastfeeding, hemoglobin, and dietary diversity
No full textIntroduction: Global goals in public health include improving maternal and infant health. Numerous interventions have been employed to achieve these goals, many of them involving educational home visits from community health workers (CHWs). The evaluations of these interventions predominantly estimate their average treatment effect, ignoring intervention mechanisms and potentially varying subgroup effects. We conducted a secondary analysis of the Healthy Future community-based home visiting intervention in rural China, which had positive effects on breastfeeding behaviors and maternal outcomes, such as mental health. We aimed to answer three additional questions: (1) Who benefited the most and least from the intervention? (2) How did the intervention improve breastfeeding behaviors? (3) What was the effect of the intervention on overall trends in breastfeeding? Paper 1 - Heterogeneous treatment effects: We used the sorted effects method to estimate individual program effects on exclusive breastfeeding (EBF), infant hemoglobin, and dietary diversity (DDS) using linear and logistic models for continuous and binary outcomes, respectively. Models included treatment, selected baseline characteristics, and first-degree interactions between treatment and baseline characteristics. Participants were clustered into top 20% and bottom 20% treatment effect groups and the characteristics of these two groups were compared. Mothers with high baseline caregiving knowledge, who gave birth vaginally, and had less social support saw the greatest improvements in EBF. Mothers who were pregnant at baseline, had less social support, and low knowledge saw the most benefits on hemoglobin. Mothers with infants born at baseline, more social support, and low knowledge had greatest improvements to DDS. Paper 2 - Mediation analysis: We decomposed the total effect of the program on a recommended breastfeeding practices composite index (mean 0, SD 1) into total direct effects (TDE) and pure indirect effects (PIE). The TDE is the average difference of counterfactual outcomes Y[a=0, ma=0] and Y[a=1, ma=0]). The PIE is the average difference of counterfactual outcomes Y[a=1, ma=0] and Y[a=1, ma=1]. Counterfactual outcomes were imputed from mediator and outcome models, and direct and indirect effects estimated, with bootstrapped 95% confidence intervals. Among all infants, breastfeeding knowledge (PIE = 0.012 SD; 95% CI 0.003, 0.022) and social support (PIE = 0.006 SD; 95% CI 0.001, 0.012) significantly mediated 16.4% and 5.3%, respectively, of the total effect of the program on the breastfeeding index. Paper 3 - Trends in breastfeeding: For each of their first six months postpartum, infants were labelled as EBF, mixed feeding (MF, feeding breast milk and other foods/liquids), or not breastfeeding (NBF). We used dynamic time warping to cluster feeding trends during the six-month period. We found seven distinct trends: always EBF (prevalence = 21.3%), always MF (33.2%), never breastfed (5.3%), EBF until the 5th month (15.1%), MF until the 5th month (13.6%), mostly EBF (6.9%), and NBF from the 3rd month (4.7%). Treatment was associated with improved odds of always EBF (ROR = 2.61, 95% CI 1.25, 5.42), MF until the 5th month (ROR = 2.52, 95% CI 1.18, 5.39), and NBF from the 3rd month (ROR = 2.82, 95% CI 1.16, 6.87) compared to being never breastfed. Mothers who always exclusively breastfed had higher education attainment and pre-intervention caregiving knowledge compared to mothers who did not. Conclusion: We identified several strengths and possible improvements to the Healthy Future program. The program successfully improved BF practices in part through modules correcting BF misconceptions and informing on BF timings. The program improved the odds of EBF in mothers with high baseline knowledge. In contrast, mothers with low baseline knowledge saw greater benefits from the program on infant hemoglobin and dietary diversity. CHWs potentially supported mothers lacking in social support, resulting in greater benefits to EBF and hemoglobin. The intervention could be improved by better targeting mothers with low baseline knowledge, possibly through modifying messaging for first-time mothers and collaborating with hospital staff during delivery. At the fifth month postpartum, the program could add messaging for mothers to avoid early supplementation. Finally, the program could add more thoughtful messaging to family members to strengthen maternal support and improve infant outcomes
Consideration of Shear Strains in Design and Construction of Heap Leach Facilities
No full textThis paper was presented at the Heap Leach Solutions Conference, October 19-21, 2025, Sparks, Nevada.Development of heap leach facilities in some project settings can be very challenging. Currently the standard of practice for heap leach facility slope designs is the use of the limit equilibrium analysis method, which does not consider strain development in geomaterials, specifically the heap leach material and the interface between the geomembrane liner system and the heap leach material. Using finite-element-method modeling, this paper considers multiple engineering applications in design and construction of heap leach facilities where consideration of shear strains within the geomaterials is crucial for the overall performance of the facilities during operations and into closure. The engineering issues considered in the paper include 1) downdrag stress and strain development over liner slopes with varying subgrade gradients, 2) impacts on a liner system due to different overliner placement and ore stacking practices, and 3) risks of strain softening and slope instability when stacking fresh (unleached) heap leach material over saturated previously leached lifts under large vertical stresses. The results of the analyses presented in this paper demonstrate that, stress and strain development in geomaterials should be considered. The recent failures of leach pads around the world reinforce this assertion
Morphological Diversity, Natural History, and Population Genomics of Two Endemic Namibian Girdled Lizards: Herero Nama Lizard (Namazonurus pustulatus) and Jordan’s Girdled Lizard (Karusasaurus jordani)
No full textI investigate morphological diversity, natural history, and population genetic structure in Namibian endemic girdled lizards. In my first chapter, I characterize sexual dimorphism in Namazonurus pustulatus (Herero Nama lizard), by using field and museum data spanning its known range. Females are larger overall, while males exhibit larger head dimensions, patterns consistent with fecundity and sexual selection. I identify size variation across elevation gradients and a growth inflection point corresponding to sexual maturity. These results provide the first comprehensive biometric data for the species and contribute to understanding sexual dimorphism in the Namazonurus clade. In my second chapter, I integrate distribution mapping, ecological observations, and morphometric analyses in Karusasaurus jordani (Jordan’s girdled lizard), revealing sexual dimorphism and morphological patterns that follow well-known biogeographic rules. My findings extend the species’ known range and indicate wider distribution, and behavioral observations suggest niche overlap among sympatric rock-dwelling species. I identify morphological findings, which challenges prior assumptions. Morphological patterns reveal that females achieve greater body size, while males exhibit larger heads and elevated scar frequencies, indicating male-male competition. Body size also shows strong associations with climatic gradients, particularly temperature and precipitation, patterns that partially align with both Bergmann’s Rule and Inverse Bergmann’s Rule. This work highlights the combined influence of sexual selection, climate, and ecological factors on trait variation in arid-adapted lizards. Finally, in my third chapter, I use RADseq data to evaluate how geography and environmental gradients contribute to population genetic structure in K. jordani. Analyses show strong population differentiation consistent with isolation by distance, reduced connectivity in peripheral populations, and reduced gene flow across dispersal barriers. Neutral processes reveal reduced gene flow across geographic barriers, supporting patterns consistent with drift, while semi-permeable zones exhibit isolation by distance. Gene-environment associations (GEAs) identify loci linked to thermal and precipitation gradients, suggesting local adaptation, and candidate loci indicate adaptations to thermal tolerance and physiological processes. Collectively, my findings reveal how neutral and adaptive forces jointly structure genomic variation in Namibia’s complex escarpment system, offering insights into biogeographic processes in Africa’s heterogenous landscapes
Extraction of Rare Earth Elements from Appalachian Coarse Coal Refuse through Heap Leaching
No full textThis paper was presented at the Heap Leach Solutions Conference, October 19-21, 2025, Sparks, Nevada.Coal and coal byproducts have been identified as potential sources of rare earth elements (REE). Most REE associated with coal preparation plants have been identified in mine refuse, which is enriched in pyritic sulfur. The weathering of refuse results in the oxidation of its pyritic shale and, thus, the formation of acidic leachates that are enriched in REE. Acid mine drainage (AMD) discharges in the Northern and Central Appalachian coal basins have the potential to produce approximately 1,000 tons per year of REE oxides. This represents approximately 5% of the total U.S. Department of Defense needs. This research aimed to determine whether existing surface deposits of coarse coal refuse (CCR), in their current sitting conditions, can be managed as an REE feedstock while controlling CCR's long-term AMD liability. This study evaluated the mechanics of heap leaching CCR to extract REE through bench-scale leaching experiments. Two CRR feedstocks were evaluated: "fresh" (subsurface, or new pile source) and "weathered" (older pile source). CCR types were tested in their current stockpiled condition. Three leaching solutions (deionized water, AMD, and AMD plus hydrogen peroxide) were evaluated. Column leaching tests were employed as the most appropriate bench-scale representation of heap leaching. The novelty of this study lay in the use of the AMD produced from the CCR itself as a leachant in the heap leach process to produce an REE-enriched leachate. Results revealed that REE concentrations in AMD increased by 116-252% in unsaturated column leaching tests of CCR. Leaching primarily occurred in the first leaching cycle, removing the REE compounds made readily available by weathering. The highest leaching efficiencies were observed in weathered CCR with AMD as the leachant
Annotated Bibliography Activity - Student Version
No full textThis group activity focuses on writing and organizing an annotation paragraph. Students will work in groups to create different parts of one annotated bibliography citation
Summary of Virtual Site Visit with the New Jersey Department of Transportation (Memorandum E)
No full textThis effort aimed to conduct a comprehensive gap analysis on the use of high-polymer (HP) binders and mixtures, identifying critical limitations, gaps, and needs through a Strengths-Weaknesses-Opportunities-Threats (SWOT) framework. In addition to addressing these gaps, the scope included documenting effective practices and lessons learned by state Departments of Transportation (DOTs). The findings provided DOTs with valuable guidance for designing, constructing, and accepting HP binders and mixtures, complementing work completed under the FHWA EDC-6: Targeted Overlay Pavement Solutions (TOPS) program. To achieve this objective, information was gathered through virtual site visits and other outreach methods with five key agencies, including a session graciously hosted by the New Jersey Department of Transportation (NJDOT).Federal Highway AdministrationUnited States Department of Transportatio
Enemy to Expert and Beyond: The Legacies of Heinz Guderian in the United States, 1945-2021.
No full textGerman General Heinz Guderian (1888-1954) has, since the late 1980s, come under increasingly critical analysis by historians and scholars of the Second World War after decades of popular praise. While scholarly work has noted Guderian’s role in propagating a self-serving mythology of the war that whitewashed the crimes of the Wehrmacht, little attention has been paid to his influence and legacy within the U.S. An analysis of Guderian’s legacy in American newspaper reporting from 1945-1954, the Marine Corps Gazette from 1953 to 2021, and in the far-right publishing house the Noontide Press from 1987 to 1991 provides a glimpse into the different ways that the German general was interpreted and understood by American observers. What emerges is not one single legacy of Guderian, but multiple conflicting legacies that demonstrate the strange and contradictory ways reputations are made, solidified, and then utilized for personal or professional gain
Enhancing Logical Reasoning and Temporal Dynamics in Complex Systems through Hybrid Logical Neural and Echo State Networks
No full textThis dissertation proposes a novel hybrid neuro-symbolic model that integrates Logical Neural Networks (LNNs) with Echo State Networks (ESNs) to enhance logical reasoning and temporal adaptability in complex systems. LNNs provide a differentiable framework for incorporating symbolic logic into neural architectures – every neuron corresponds to a logical formula component, enabling interpretable reasoning and robust handling of knowledge. ESNs, a form of reservoir computing, contribute a dynamic “memory” through a fixed, randomly connected recurrent layer (the reservoir) that projects inputs into high-dimensional state representations. Coupling these paradigms synergistically combines the strengths of symbolic logic with those of neural networks, overcoming key limitations of each.The versatility of the LNN–ESN hybrid is demonstrated across three distinct domains: cybersecurity, robotics, and natural language processing (NLP). In cybersecurity, we develop an advanced Intrusion Detection System (IDS) that leverages the hybrid model to detect network intrusions. The LNN component encodes expert security rules and logical constraints, while the ESN learns temporal patterns of network traffic, together improving detection accuracy and significantly reducing false alarms by combining signature-based and anomaly-based detection. In robotics, we apply the model to temporal logic reasoning tasks, where autonomous agents satisfy Linear Temporal Logic (LTL) specifications. The ESN’s reservoir captures temporal context from sensor inputs, and the LNN infuses logical constraints, enabling robots to conform to complex task specifications over time. In NLP, we illustrate how the hybrid model can maintain logical consistency in language understanding and reasoning. By remembering sequential context (ESN) and applying formal logical rules (LNN) to that context, the model adeptly handles tasks like structured text inference and multi-turn dialogue with improved coherence, addressing known limitations of purely neural language models in logical reasoning.
The research shows that the LNN–ESN hybrid achieves state-of-the-art performance in each domain, exceeding the accuracy of conventional deep learning and other neuro-symbolic techniques, while offering explainable insights into its decisions. The introduction of logical constraints into the temporal dynamics of ESN yields accurate models that are verifiable against domain knowledge (e.g. security policies, formal logic rules). Key contributions of this dissertation include: (1) the design of a unified LNN–ESN architecture and learning algorithm; (2) empirical demonstration of its generalizability across heterogeneous domains; (3) enhancements to intrusion detection and robot planning via integrated logic-based reasoning; and (4) comparative analyses showing the hybrid model’s superiority over existing hybrid AI approaches in adaptability and interpretability. The broader significance lies in advancing neuro-symbolic AI as a practical paradigm. Finally, we discuss limitations and provide a roadmap for future work to extend the model’s scalability and usability, laying the groundwork for next-generation AI systems
An Exploration of the Effect of Instructor Type and Location on Dual Enrollment Course Outcomes
No full textAn exploratory, quantitative methodology was used to investigate the effects of instructor type and course location on the academic achievement of dual enrolled high school students. The purpose of this study was to explore high school students’ academic achievement in dual enrollment courses through a community college program. This study was guided by one key research question: Do statistically significant differences in dual enrollment academic achievement exist when groups are established by demographic variable (i.e., course location, instructor type, gender, race ethnicity) based on course grades? An existing deidentified data set from one community college served as the data source. The samples derived from a dataset of 2,735 records of dual enrollment courses belonging to a total of 1,598 students. The dependent variables were the final course grades associated with the dual enrollment course. The independent variables were instructor type, course location, gender, and race/ethnicity. Exploratory analysis utilized descriptive statistics, chi-square, and binomial logistic regression. Results revealed that the grade distribution for the dual enrollment courses was not normal, in fact distribution was negatively skewed. Through a binomial logistic regression analysis, results indicated there were fewer odds that a student would fall into a high achievement category when taking a dual enrollment course from a college instructor. Lastly, chi-square analysis demonstrated an association between college instructors and academic achievement and gender. The results are discussed in terms of implications for practice and further research
Balanced Mix Design of Asphalt Mixtures: Challenges and Opportunities
No full textThis Technical Brief summarizes key challenges State Departments of Transportation (DOTs) face in adopting Balanced Mix Design (BMD) that are categorized into three focus areas: management (M), technical (T), or overlapping technical-managerial (TM). It also highlights associated opportunities and actionable steps to support effective BMD implementation.U.S. Department of TransportationFederal Highway Administratio