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abstract: The experience base of practitioners with expansive soils is largely devoid of directly measured soil suction. This historical lack of soil suction measurement represents an impediment to adoption of modern unsaturated soil engineering to problems of expansive soils. Most notably, soil suction-based analyses are paramount to proper design of foundations in expansive soils. Naturally, the best method to obtain design suction profiles is to perform an appropriate geotechnical investigation that involves soil moisture change-appropriate drilling depths, sampling intervals, and requisite laboratory testing, including suction measurement. However, as practitioners are slow to embrace changes in methodology, specifically regarding the adoption of even relatively simple suction measurement techniques, it has become imperative to develop a method by which the routine geotechnical procedures currently employed can be used to arrive at acceptable approximations of soil suction profiles. Herein, a substitute, or surrogate, for soil suction is presented, such that the surrogate agrees with observed field soil suction patterns and provides estimates of soil suction that are acceptable for use in practice. Field investigations with extensive laboratory testing, including direct suction measurement, are used in development of the soil suction surrogate. This surrogate, a function of water content and routinely measured soil index properties, is then used in estimation of field expansive soil suction values. The suction surrogate, together with existing geotechnical engineering reports, is used to augment the limited existing database of field soil suction profiles. This augmented soil suction profile database is used in development of recommendations for design suction envelopes and design suction profiles. Using the suction surrogate, it is possible to proceed from the beginning to the end of the Suction-Oedometer soil heave/shrinkage analysis without directly measuring soil suction. The magnitude of suction surrogate-based heave estimates is essentially the same as heave estimates obtained using direct soil suction measurements. The soil suction surrogate-based approach, which uses a complete-stress-state approach, considering both net normal stress and soil suction, is an intermediate step towards the adoption of unsaturated soil engineering in expansive soils analyses, wherein direct soil suction measurements are routinely made. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2019

In this dissertation, we investigate four distinct and interrelated problems for high-dimensional inference of mean vectors in multi-groups. The first problem concerned is the profile analysis of high dimensional repeated measures. We introduce new test statistics and derive its asymptotic distribution under normality for equal as well as unequal covariance cases. Our derivations of the asymptotic distributions mimic that of Central Limit Theorem with some important peculiarities addressed with sufficient rigor. We also derive consistent and unbiased estimators of the asymptotic variances for equal and unequal covariance cases respectively. The second problem considered is the accurate inference for high-dimensional repeated measures in factorial designs as well as any comparisons among the cell means. We derive asymptotic expansion for the null distributions and the quantiles of a suitable test statistic under normality. We also derive the estimator of parameters contained in the approximate distribution with second-order consistency. The most important contribution is high accuracy of the methods, in the sense that p-values are accurate up to the second order in sample size as well as in dimension. The third problem pertains to the high-dimensional inference under non-normality. We relax the commonly imposed dependence conditions which has become a standard assumption in high dimensional inference. With the relaxed conditions, the scope of applicability of the results broadens. The fourth problem investigated pertains to a fully nonparametric rank-based comparison of high-dimensional populations. To develop the theory in this context, we prove a novel result for studying the asymptotic behavior of quadratic forms in ranks. The simulation studies provide evidence that our methods perform reasonably well in the high-dimensional situation. Real data from Electroencephalograph (EEG) study of alcoholic and control subjects is analyzed to illustrate the application of the results.

This aim of this study was to answer the research question: "What is the Life Pattern of the Person with Spinal Cord Injury?" The unitary appreciative inquiry design, which has conceptualized through Rogers' (1986) science of unitary human beings, provided an approach for understanding the phenomenon in the context of human wholeness. The data, obtained through the methodology of unitary appreciative inquiry, led to the development of individual synopses for each of the participants. Once the synopses were completed, a composite pattern profile was constructed by the researcher that was indicative of the life pattern of people with spinal cord injury. The participants in the study validated the synopsis and pattern profile as accurate representations of their experience with spinal cord injury. This qualitative study, which was comprised of eight people who had undergone a spinal cord injury more than two years prior to the study, discovered three shared pattern manifestations: depersonalization; loss; and hopelessness. Although each person within this inquiry had a very good physical outcome concerning their spinal cord injury, the participants were not pleased with their current state of being. The pattern of despair, which was validated by the participants, was manifested through the profound sense of depersonalization, loss, and hopelessness.

Writing self-efficacy is a vital component to a students’ motivation and will to succeed towards writing. The measurement of writing self-efficacy over the past 40 years, despite its development, continues to largely be represented by Confirmatory Factor Analysis models that are limited due to their restricted item to factor constraints. These constraints, given prior literature and the theoretical understanding of self-efficacy, do not adequately model construct- relevant psychometric multidimensionality as a product of conceptual overlap or a hierarchical or general factor. Given this, the present study’s purpose was to examine the adapted Self-efficacy for Writing Scale (SEWS) for the presence of construct-relevant psychometric multidimensionality through a series of measurement model comparisons and person-centered approaches. Using a sample 1,466 8th, 9th, and 10th graders, a bifactor exploratory structural equation model was found to best represent the data and demonstrate that the SEWS exhibits both construct-relevant multidimensionality as a function of conceptual overlap and the presence of a hierarchical theme. Using factor scores derived from this model, latent profile analysis was conducted to further establish validity of the measurement model and examine how students disaggregate into groups based on their response trends of the SEWS. Three profiles emerged greatly differentiated by global writing self-efficacy, with obvious and substantively varying specific factor differences between profiles. Concurrent, divergent, and discriminant validity evidence was established through a series of analyses that assessed predictors and outcomes of the profiles (e.g. demographics, standardized writing assessments, grades). Theoretical and educator implications and avenues for future researcher were discussed.

The shootings and killings across the country of unarmed African American males by police officers, has become a topic of discussion. Previous research indicates that African American males, in comparison to other groups, are more likely to have adverse encounters with law enforcement officials. The purpose of this phenomenological study was to explore the experiences and perceptions of African American males in Prince Georges' County regarding encounters with the Prince Georges' County Police Department and how the relationship can improve. Max Weber's social action theory was used to examine perception and purposive sampling aided in gathering this information from a group of 10 African American male participants. Interviews were transcribed and then coded and analyzed using a modified Van Kaam procedure. Findings suggest most participants believe Prince Georges County police are doing a good job. The participants also noted specific strategies, including better utilization of seminars, meetings, and other collaborative efforts may improve police-community interactions and relations. The implications for positive social change include recommendations to law enforcement executives in the Prince Georges' County Police Department to utilize the insight gained through this study to better understand how they are perceived by the African American males in the county and strengthen outreach and collaboration efforts. Following these recommendations may improve the nature of police-community relations thereby advancing public safety within the county and with the African American community in particular.

L’analyse des cheveux est à présent reconnue comme un outil pertinent dans le domaine de la toxicologie car elle permet de fournir un historique des habitudes de consommation d’un individu, qu’il s’agisse d’une consommation ponctuelle ou répétée.L’analyse d’un seul cheveu par désorption/ionisation laser assistée par matrice (MALDI) offre de nombreux avantages par rapport aux techniques conventionnelles : la quantité de cheveux est réduite, la préparation des échantillons est simplifiée et les images sont acquises avec une résolution spatiale très élevée (~100 µm). L’imagerie MALDI (MALDI-MSn) nous a permis de caractériser et de cartographier l’évolution des quantités de xénobiotiques le long du cheveu avec une très haute résolution spatiale sans une préparation trop longue ou trop complexe des échantillons au préalable.La spectrométrie de masse MALDI couplée à des plaques micro-réseaux (Microarrays for Mass Spetrometry, MAMS) nous a permis de développer une méthode pour effectuer une semi-quantification de la cocaïne, de la benzoylecgonine, de l’ecgonine méthyl ester et du cocaéthylène à partir d’une quantité de 1 mg de cheveux et 2 heures d’extraction ; les résultats sont bien corrélés avec une méthode de quantification validée. Cette méthode est pertinente lorsque des résultats urgents sont requis. Au total, le développement de ces deux applications nous a permis de démontrer la pertinence de la spectrométrie de masse MALDI dans l’analyse toxicologique du cheveu. Les perspectives consistent à améliorer ces protocoles afin de les transposer en routine et de développer des méthodes de screening large par spectrométrie de masse MALDI. / Hair analysis is now recognized as a relevant tool in the field of toxicology. It provides a precise history of an individual’s exposure to drugs, whether it is a punctual or repeated consumption.Matrix-Assisted Laser Desorption/Ionization (MALDI) has many advantages over conventional techniques: the amount of hair needed is reduced, the sample preparation is simplified and the images are acquired with high spatial resolution (~ 100 μm).MALDI (MALDI-MSn) imaging allowed us to characterize and map the evolution of drugs amounts along the hair with very spatial resolution avoiding long and complex pre-sample preparation.MALDI coupled to Microaarays for Mass Spectrometry (MAMS) allowed us to develop a method for semi-quantitation of cocaine, benzoylecgonine, ecgonine methyl ester and cocaethylene using 1 mg of hair and 2 hours of extraction; the results are well correlated with a validated quantification method. This method is relevant when urgent results are required.In total, the development of these two applications demonstrates the relevance of MALDI mass spectrometry in the toxicological analysis of hair. The prospects are to improve these protocols in order to transpose them routinely and to develop large screening methods by MALDI mass spectrometry.

Objetivou-se avaliar o efeito da inclusão de óleo de soja e óleo de linhaça na dieta de vacas em lactação sobre a produção, composição de leite e parâmetros sanguíneos. Foram utilizadas 18 vacas de raça Holandês, com produção média de 25 ± 4 kg/dia em 153 ± 62 dias em lactação. As vacas foram distribuídas em delineamento quadrado latino, com 6 quadrados contemporâneos, 3 períodos e 3 tratamentos e arraçoadas de acordo com os seguintes tratamentos: 1) Controle (CT): sem adição de óleo; 2) Óleo de Soja (OS): 5% de adição de óleo de soja no concentrado como fonte de ômega-6 (% MS); 3) Óleo de Linhaça (OL): 5% de adição de óleo de linhaça no concentrado como fonte de ômega-3 (% MS). A produção de leite não foi alterada mas a suplementação com óleo diminuiu o consumo de matéria em 1.93 kg/dia/vaca. A produção de gordura foi significativamente menor quando as vacas receberam suplementação com óleo vegetal (3,37, 2,75 e 2,89 % para CT, OS e OL, respectivamente). No entanto, ambos os óleos de soja e linhaça diminuíram a concentração de ácidos graxos saturados (65,72, 54,09 e 54,26 para CT, OS e OL respectivamente) e aumentaram a quantidade de ácidos graxos insaturados no leite (34,24, 45,91 e 45,74 para CT, OS e OL respectivamente) e diminuíram a relação entre os ácidos graxos saturados/insaturados (18,28, 10,41 e 4,52 para CT, OS e OL respectivamente). Além disso, o óleo de soja e de linhaça aumentaram significativamente a teor de ácidos graxos mono (24.95, 30.89 e 31.61%, para CT, OS e OL respectivamente) e poli-insaturados (2,4, 3,0 e 2,97 para CT, OS e OL respectivamente) na gordura do leite. As variáveis sanguíneas aspartato aminotransferase, gama glutamil transferase, ureia, albumina, creatinina e proteínas totais não foram alteradas. Por outro lado, o colesterol total, HDL e LDL foi maior no grupo suplementado com os óleos vegetais. A suplementação com óleos vegetais ocasionou diminuição do consumo de matéria seca, melhorou relação ω6/ω3 do leite, sem alterar profundamente as variáveis sanguíneas de vacas lactantes. / The use of polyunsaturated oils in the ruminant diet has been shown to be an efficient alternative to improve the lipid composition of cows\' milk, aiming to improve human health. The objective of this study was to evaluate the effect of soybean oil and linseed oil in the diet of lactating cows on the production, milk composition and blood parameters. 18 Holstein cows were used, with a mean production of 25 ± 4 kg / day in 153 ± 62 days in lactation. Animals were distributed in a Latin square design, with 6 contemporary squares, 3 periods and 3 treatments, and ratified according to the following treatments: 1) Control (CT): without addition of oil; 2) Soybean oil (SO): 5% addition of soybean oil in the concentrate as a source of omega-6 (% DM); 3) Flaxseed oil (FO): 5% addition of linseed oil in the concentrate as a source of omega-3 (% DM). Milk yield was not altered but the supplementation with oil decreased the DM intake by 1.93 kg/day. Fat production was significantly lower when cows were supplemented with vegetable oil (3.37, 2.75 and 2.89% for CT, SO and LO, respectively). However, both soybean and linseed oils decreased the concentration of saturated fatty acids (65.72, 54.09 and 54.26 for CT, SO and LO respectively) and increased the amount of unsaturated fatty acids in milk (34.24, 45.91 and 45.74) and decreased the relationship between saturated / unsaturated fatty acids (18.28, 10.41 and 4.52). In addition, soybean and flaxseed oil increased significantly in monounsaturated fatty acids (24.95, 30.89 and 31.61% for CT, SO and LO respectively) and polyunsaturated fatty acids (2.4, 3.0 and 2.97) in milk fat. Blood variables aspartate aminotransferase, gamma glutamyl transferase, urea, albumin, creatinine and total proteins were not altered. On the other hand, total cholesterol, HDL and LDL were higher in the group supplemented with vegetable oils. Supplementation with vegetable oils caused a reduction in dry matter intake, improved n-6/n-3 ratio of milk, without profoundly altering the blood variables of lactating cows.

In a dry-land winter wheat field, patterns of mineral nitrogen distributions were investigated before and after fertilizer additions. Large differences in the added mineral nitrogen recoverable three weeks after treatment were found to be specific to nitrogen source and treatment within source. Initial losses averaged 50 percent for urea treatments, 40 percent for calcium nitrate treatments, and varied from a loss of 18 percent to a gain of 22 percent for ammonium nitrate treatments. Ammonium sulfate proved the most variable with a 36 percent average loss for the before-planting treatment and a 61 percent gain for the after-planting treatment. This initial gain and loss behavior correlated at the 2 percent level of significance with the subsequent grain yield (r=0.774, 8 df), and was still discernable in soil test results of late April, where total mineral nitrogen depletion since before treatment correlated positively at the 10 percent level of significance with the nitrogen loss found 3 weeks after treatment. For a small sample of nine plots, a late July sampling revealed that depletions of mineral nitrogen since April were much more predictive of grain yields than were the actual April-N levels (r2=0.787 versus r2=0.460). This result confirms the large role played by differential moisture stress regimes in the field, since depletions during the drying season of late spring and early summer depend on the availability of moisture. Initial fertilizer behavior, determining fertilizer losses before the onset of crop usage, and a favorable later moisture regime were seen as the two largest determinants of yield under the conditions of this experiment. Since the latter factor is largely beyond further control, the former is the only factor open to manipulation. Generally, after planting treatments were lower in initial losses of mineral nitrogen, and also generally provided somewhat higher surface mineral nitrogen levels in early spring, which was found to be weakly correlated with yield. Surface accumulations in early spring can only be beneficial if sufficient spring moisture is available for downward transport into the root zone, however, and a drier spring than prevailed during this experiment could forseeably reverse this relationship by keeping such surface nitrogen accumulations from becoming available to the plant in spring.

Root respiratory response of mature Atriplex confertifolia plants growing in established communities was measured during two growing seasons using freshly excised root segments and gas chromatography techniques. Respiratory response at fixed test temperatures changed significantly during the growing season, and this pattern of respiratory adjustment varied for root segments located at different depths in the soil profile. Respiration measured at a constant test temperature was highest during early sumner, and declined to minimum values in late summer and fall. Root segments taken from the top 30 cm of the soil profile displayed peak activity several weeks before root segments from greater depths reached maximum activity. The significance of these patterns of respiration is discussed in relation to the carbon balance of Atriplex plants and the uses of respiratory energy within the root system.