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Unavoidable Immersions and Topological Minors of k-edge-connected Graphs
No full textIn this work, we present results concerning the unavoidable structures in large and infinite k-edge-connected graphs. These results are inspired by the classical result of Ramsey, who proved that for every positive integer r, every sufficiently large graph contains as an induced subgraph either Kr or . We consider different graph containment relations, focusing primarily on the immersion relation. In the case of finite graphs, we provide the unavoidable immersions of 4-edge-connected graphs and prove that linear edge-connectivity suffices to immerse the graph Ct,r.
This dissertation also considers infinite graphs. We present the unavoidable topological minors of infinite 2- and 3-edge connected graphs, and we use these results to find the unavoidable immersions of graphs in these classes. We also provide results concerning the unavoidable immersions of graphs containing a vertex with infinitely many neighbors, as well as those of arbitrary (4k-1)-edge-connected graphs
En Clave Tania León and Roberto Sierra: autochthonous music of Cuba and Puerto Rico, contemporary music composition and the \u27Puente\u27 in between
No full textThis document is in two parts. The first examines selected works of Latin-American composers Tania León and Roberto Sierra. Both composers cite their cultural background as a force that shapes their artistic expression. Many of their works are titled in Spanish, with compositions referencing their homelands in subject and narrative, and incorporate the autochthonous music(s) of Cuba and Puerto Rico. Elements of these afrodiasporic musical traditions can be found in their works: Alegre, Batá, Stride, (Leon), Loiza, and Concerto for Viola (Sierra), each examined here.
Autochthonous musical elements are highlighted in score excerpts and described using the language and nomenclature typical of their genres. Through examining each composer\u27s work, I hope to illustrate how those cultural elements are developed beyond their idiomatic settings and incorporated in the construction of a large-scale contemporary music composition reflecting their personal expression and unique stylistic paths.
The second part presents some research into bomba, an autochthonous music of Puerto Rico. Interviews, articles and recordings are cited as sources for information about this genre’s history, development and modern practice. Bomba was first observed as a practice in Black communities in Puerto Rico in 1797 and has parallel music traditions in other colonized areas throughout the Caribbean and New Orleans.1 Bomba maintained relevance as a folk and popular music in Puerto Rico throughout the early twentieth century until it was replaced in popular music by salsa and the “Cubanization” of other Latin American music styles.2
Materials studied in this research process are incorporated into the writing of a new musical work, Bámbulas. This original composition incorporates both musical and soundscape elements of Puerto Rican bomba reinterpreted by a non-standard ensemble. The intent of this composition is to make use of some of bomba’s idiomatic elements and develop those materials over the course of a long-form composition, evoking bomba’s cultural setting and creating an expression of the life that encircles the music.
1Reinaldo L. Roman, “Scandalous Race: Garveyism, the Bomba, and the Discourse of Blackness in 1920s Puerto Rico.” Caribbean Studies 31, no. 1 (2003): 246,247. http://www.jstor.org/stable/25613394.
2Peter Manuel, “Puerto Rican Music and Cultural Identity: Creative Appropriation of Cuban Sources from Danza to Salsa.” Ethnomusicology 38, no. 2 (1994): 259. https://doi.org/10.2307/851740
A Defense of Judgment By Michael W. Clune. London & Chicago: The University of Chicago Press, 2021. ISBN-13: 978- 0- 226- 77029- 1
No full textModeling Nutrient Functions: Strengthening the Reliability and Applicability of Ecosystem Service Models for Land Use Decision-Making
No full textEffective water quality management requires a clear understanding of both the magnitude and spatial distribution of nutrient retention and export across dynamic landscapes, given their direct implications for drinking water supply, ecosystem integrity, fisheries, and recreational uses. Equally important is anticipating trade-offs from management actions, which can alter ecosystem functioning and the flow of services. Modeling tools provide a means to predict nutrient outcomes, evaluate these trade-offs, and support decision-making; however, their utility is often constrained by persistent challenges, including model uncertainty, limited applicability in data-scarce regions, and insufficient empirical foundations to inform scenario-driven decision-making. This dissertation addresses these gaps by advancing nutrient function modeling to enhance the reliability, applicability, and operational relevance of ecosystem service (ES) tools for land-use decision-making. Using the InVEST Nutrient Delivery Ratio (NDR) model, it provides both methodological and empirical contributions that improve model performance. Chapter 2 develops a standardized framework for systematic model evaluation using long-term water quality data, strengthening model reliability for watershed management. Chapter 3 expands this framework by integrating machine learning to impute historical data and transfer model parameters from well-monitored to under-monitored catchments based on hydrogeological similarity, enabling spatially explicit ES assessments where monitoring is sparse. Chapter 4 builds a longitudinal empirical foundation through a 60-year, multi-scale analysis in Puerto Rico, demonstrating that both landscape composition and spatial configuration critically influence nutrient dynamics essential for scenario-based modeling to inform decision-making. The contributions of this dissertation are transferable to other regions, offering tools to generate spatially and temporally explicit nutrient retention estimates, identify nutrient export hotspots, and guide adaptive land-use planning. This dissertation provides a foundation for refining nutrient function models, integrating scenario-based simulations, and supporting relevant strategies for water quality policy and ecosystem management
Orbital distortion and parabolic channel effects transforming minima in molecular ionization probabilities into maxima
No full textIn the tunneling regime and at sufficiently low field amplitudes, the shape of orientation-dependent molecular ionization rate curves usually resembles the shape of the ionized orbital. As the ionizing field strength increases, the shape of the ionization rate can deviate from this pattern. The oft-cited explanation is that the increasing contribution of excited states relative to the ground state modifies the distribution. In this paper we show that orbital distortion and parabolic channel effects, which are independent of excited-state effects, can also significantly modify the angular dependence of the yields of widely studied molecules where excited state effects are negligible. For example, as the ionizing field increases we find that (1) in CO, orbital distortion is responsible for the switch of the position of the global maximum in the orientation-dependent ionization rate to the opposite orientation, and (2) in CH3Br, the interplay between orbital distortion and parabolic channel effects transforms a local minimum to a local maximum. To simulate orbital distortion and parabolic channel effects, we use the one-electron weak-field asymptotic theory including the first-order correction [OE-WFAT(1)] in the integral representation. Since OE-WFAT(1) incurs expensive computations when the number of orientation angles is large, we also reformulate the original OE-WFAT(1) algorithm into a partial-wave expansion form, which greatly enhances the efficiency of the method
A Multi-Level Analytics Framework for Understanding CHF and Readmissions: Integrating Natural Language Processing of Literature with EHR-Based SDOH Modeling
No full textThere is increasing acknowledgment of the impact that Social Determinants of Health (SDOH) have on health outcomes, especially for chronic illnesses. Chronic conditions such as congestive heart failure (CHF) are the leading cause of hospitalization among older adults in the United States. Understanding the complex connections between SDOH, socioeconomic factors affecting health, and CHF can help reduce the high rates of morbidity, mortality, readmission, and costs associated with CHF. In this project, we aim to explore known and unknown SDOH influences on CHF by analyzing patient data from the electronic health records at Our Lady of the Lake Regional Medical Center (OLOL RMC), supported by a modern approach that uses unsupervised machine learning techniques to identify themes and hidden relationships from thousands of medical publications on SDOH and CHF. This approach is more efficient than time-consuming or labor-intensive traditional review methods. The specific goal of this study is to thoroughly examine the relationship between SDOH and CHF. To accomplish this, we will apply a topic modeling technique called Latent Dirichlet Allocation and hierarchical clustering using the statistical software R to identify specific trends, patterns, and correlations. Then, in collaboration with OLOL RMC, we will validate these relationships using SDOH information extracted from the hospital’s electronic health records. Finally, we will analyze the relationships between readmission rates, the Epic Risk Score, and sepsis OPA alerts. By identifying key SDOH factors that significantly impact CHF outcomes, we aim to guide the development of interventions and policies to reduce these disparities and promote health equity. The findings and connections established by this research will lay a foundation for future studies on CHF and SDOH, which are of interest to NIH and national nonprofits such as the American Heart Association
DEVELOPMENT OF BIOMATERIALS FROM LIGNIN GRAFTED POLYMERS FOR MULTIPLE APPLICATIONS
No full textLignin (LN) is one of the most abundant polymers in nature, but it is usually considered a waste byproduct of the pulping industry. The goal of this work was to engineer sustainable materials from lignin-grafted polymers, in the form of nanoparticles and films. Lignin nanoparticles (LNPs) were developed as a delivery system for methoxyfenozide (MFZ) to facilitate translocation of the nonsystemic, hydrophobic pesticide, from roots to the leaves of soybean plants, where it targets the soybean looper—a common soybean pest. Translocation of the nanodelivered MFZ was significantly enhanced, as supported by MFZ concentrations of 1.72 μ g/g in the leaves compared to 0.39 μ g/g for the control, free MFZ. Next, amphiphilic co-polymer films were produced from alkaline lignin, and sodium lignosulfonate grafted with poly(lactic-co-glycolic) acid (PLGA) at two ratios LN:PLGA (1:4, and 1:6 w/w) using an interphase formation technique. Films presented two sides with different surface properties, as measured by contact angle and roughness. Mechanical properties of the films were also affected by the lignin type and lignin: PLGA ratio. The stability of the same type of films was tested by storing them at two different relative humidities: 30 and 70% over a period of 12 months. Results showed that lignin-grafted films maintained their roughness, contact angle, and UV shielding properties consistent over the 12-month period and maintained their mechanical integrity compared to the neat polymer films. Next, lignin was grafted with three different polyesters, PCL, PLGA, and PLA, for the development of packaging films. Lignin grafting had little effect on the mechanical and functional properties of the films while increasing significantly their UV-absorption, of importance for packaging UV sensitive products. These studies clearly show that lignin NPs were effective as nano delivery systems for hydrophobic agrochemicals, and films produced from lignin-grafted polymers showed suitable mechanical characteristics, increased UV-absorption, and stability at multiple relative humidity conditions. This demonstrates that lignin is a versatile polymer to be employed in the development of biomaterials for agrochemical and packaging applications
Louisiana Cattle Producers\u27 Willingness to Pay For Alternative Management Practices
No full textThis paper analyzes beef cattle producers’ preferences and willingness to pay for market-available production practices and technologies. Primary data was collected via an electronic survey with mostly Louisiana producers. A discrete choice experiment (DCE) highlights the tradeoffs between the production practices and technologies presented in the study. Average profit margin per calf is expected to influence the operation’s adoption capacity and producers’ management decisions; ultimately, impacting the likelihood of adoption. Summary results correlate with previous literature in that most cow-calf operators in the region are small-scale, with most income dependence coming from off-farm. As a result, adoption decisions are driven by the type of service and potential return. In this study, reproductive services, estrus synchronization with a natural service insemination, vaccinations, and nutritional practices all expressed a strong positive influence on a producer’s decision to adopt a bundle of technologies. Estrus synchronization with artificial insemination (AI) and forage tests displayed weak evidence for producers whose profit margins were known. However, producers consistently preferred and had the largest willingness-to-pay (WTP) for reproductive services and full-year nutritional programs. By identifying trends within the population, this study contributes to developing targeted extension programs, policies, and incentives to enhance technology adoption rates among small cow-calf producers
A Historical Inquiry into the Evolution and Perpetuation of University Commencement Ceremonies in Louisiana, 1800s to the Present
No full textThis study explored and documented the history and evolution of college commencement ceremonies at four Louisiana universities from the 1800s to the present. The study utilized historical inquiry and drew upon the use of archival materials, programs, photographs, newspaper accounts, institutional records, press releases, institutional websites, and observation to address the research question. The research question for the study was, “How have college commencement ceremonies in Louisiana evolved from the 1800s to the present, and in what ways do these ceremonies reflect the state\u27s unique cultural heritage and institutional traditions?” The findings reveal that commencement ceremonies have evolved from small, elaborate exercises to large-scale events hosted in athletic arenas and stadiums. These ceremonies have been significantly shaped by political, societal, economic, and other historical forces. Their importance to both the student experience and operations of the universities has been demonstrated over time, particularly during the COVID-19 pandemic. The study contributes to higher education history by illuminating how certain Louisiana institutions use commencement as a ritual to express continuity, identity, values, status, and influence as well as show how the institutions have changed, adapted, and been transformed over time