We propose the use of Latent Class Analysis methods to analyze the covariate inclusion patterns across specifications resulting from Bayesian model averaging exercises. Using Dirichlet Process clustering, we are able to identify and describe dependency structures among variables in terms of inclusion in the specifications that compose the model space. We apply the method to two datasets of potential determinants of economic growth. Clustering the posterior covariate inclusion structure of the model space formed by linear regression models reveals interesting patterns of complementarity and substitutability across economic growth determinants.

The Strong Black Woman Schema (SBWS) refers to the collective believes, behaviors, resources and responses Black women are socialized to embody. The SBWS was developed as a positive counterimage to the negative stereotypes of Black women, such as the mammy or the jezebel, and is an important image among Black women. Observations suggest that the SBWS may affect how Black women experience and interpret stress and mental illness. I assert the SBWS may serve as one comprehensive explanation for the mental health outcomes observed for Black women. Qualitative and quantitative studies have identified a set of characteristics (i.e. strength, emotion regulation, caretaking) related to the schema. However, scales developed to measure the schema lack the ability to isolate adequately a unique typology for Black women. I argue that the SBWS is representative of a specific compilation of psychosocial resources (i.e. mastery, self-efficacy, resilience, self-esteem) representative of the cultural response to historical experiences of racism and sexism. I explore how the SBWS influences the reporting of depressive symptoms, depression and anxiety through a secondary data analysis of African American, Caribbean Black and White American women using data from the National Survey of American Life. Through a three part analysis, I answer the following questions: 1) Is a compilation of psychosocial measures an appropriate measure of the Strong Black Woman Schema? 2) What sociodemographic factors influence distinct typologies reflective of at least one uniquely Black form of the Strong Black Woman Schema? And 3) Does the Strong Black Woman Schema influence depressive symptons, depression, and anxiety? Results of this study clarify how socio-cultural aspects of oppression influence the mental health of Black women.

Fire presents a great risk to humans and their possessions. Polymeric compounds are highly flammable and compounds are added to increase their fire resistance. These additives are referred to as flame retardants. Intumescent flame retardants are systems that form a carbon rich foam on the surface of the polymer during thermal degradation. A new field of metal catalysed intumescence is discussed in this document. The influence of both the metal ion and organic backbone of polyhydroxylcarboxylic acid metal salts was studied. The intumescence and foaming properties of selected salts were studied in more detail. Gluconic acid proved to be the best intumescent and showed the best combination of carbon char yield, foam structure and volume, stability and open flame characteristics. As a general rule of thumb, the char volume and structure improved with an increased number of hydroxyl groups in the compound. Carbon char yield increased with an increase in the number of hydroxyl groups for a constant number of carbons in the complex. The number of acid groups in the compound played a lesser role in intumescence. Most metal complexes catalyse intumescent decomposition of polyhydric compounds such as polyhydroxylcarboxylic acids and pentaerythritol. The reduction in the volatilisation losses implies that the metal cations catalyse carbonisation reactions in the polyhydroxyl compound. Unfortunately, the resultant carbon-foams are unstable: the metal residues also catalyse the further oxidative degradation of the char. The low thermal stability of the compositions tested, as well as the afterglow effect makes them unsuitable for use as flame retardant additives in plastics. From the studies of the different metal complexes with acetylacetone and gluconic acid, it was concluded that the calcium ion exhibited the most promise. When pyrolysed in air with an open gas flame or in a furnace, calcium gluconate monohydrate produces voluminous foam. The foam is of a closed cell structure, densely packed and has no mechanical strength. The cell walls are very thin (5 to 50 nm) and the cells are between 50 µm and 200 µm in size. If the sample is compressed before heating, the resultant foam produced during pyrolysis is less voluminous than that of the loose powder. The BET surface area of the calcium gluconate monohydrate foamed at 300°C for 5 min. is 16.0 m2/g. The foam produced after 5 min heating at 300°C has a thermal conductivity similar to standard polystyrene foam. Adding leached silica to the calcium gluconate monohydrate increases mechanical strength of the foam, but influences the foam volume negatively. The optimum silica level was calculated to be 1:1 gluconate to silica on a mole ratio (11.8% SiO2 by mass). The mechanical strength of the foam can also be increased with the addition of expandable graphite. The graphite has a lesser influence on the foam volume than the silica, but also reduces the foam volume. However, the addition of the expandable graphite gives the sample more .opening. force, as the foam volume of a compressed sample pyrolysed, is similar to that of the heated loose powder. Calcium gluconate monohydrate starts to degrade at 120°C, losing its crystal water and shows a mass loss of 4% at 180°C. The exothermic peak (shown in the DSC/TGA data) associated with the metal catalysed carbon oxidation (afterglow) is observed at 570°C in air. For the calcium gluconate monohydrate the transition from CaCO3 to CaO occurs above 650°C in air. It has been shown that the foaming of polyhydroxylcarboxylic acids is due to the formation of water vapour during degradation. For calcium gluconate monohydrate, foaming starts due to the loss of crystal water and is continued by the loss of hydroxyl groups as water. The bulk of the foaming is due to the second reaction. It has been shown that compounds with crystal waters produce a more voluminous and lower density foam. The foam is an amorphous carbon rich residue. The molecular mass of the carbon residue increases up to a heating temperature of 300°C. This implies that the carbon residue crosslinks during formation, forming a stretchable cell wall for the foam. Compounds with a .free. hydroxyl group at the end of the carbon chain produce a foam of larger volume and lower density. This supports the crosslinking theory. The foam produced when calcium gluconate monohydrate is heated for 5 min at 300°C in air is of very low density . 2.5 kg/m3 based on residual mass. The density of the calcium gluconate monohydrate pyrolysed at 1000°C for 5 min in air yields a CaO with a density of 20 kg/m3 . This implies that the high temperature pyrolysis of calcium gluconate can produce an inorganic oxide of low bulk density and possible high specific surface area. The BET surface area of CaCO3 from the gluconate pyrolysed at 600°C is ~ 12 m2 /g. An intumescent coating containing calcium gluconate monohydrate, leached silica and expandable graphite as a system was prepared and compared to commercial formulations. This gluconate based system was at least as efficient as the commercial formulations when painted on balsa wood planks or aluminium plates. On cardboard sheets it did not perform as well as the commercial systems. More work should be done to overcome the afterglow effect observed with metal- based intumescent systems. The crystal structure of calcium gluconate monohydrate should be determined as to understand the decomposition better. It is unclear whether the decomposition is catalysed inter- or intramolecularly. / Thesis (PhD(Chemical Engineering))--University of Pretoria, 2005. / Chemical Engineering / unrestricted

Research over the last few decades has consistently found that fathers are not routinely included in the provision of child welfare services. The current study examined whether ambivalent sexism on the part of child welfare workers was related to their beliefs about involving fathers. Ambivalent sexism theory posits that gender stereotypes include subjectively positive beliefs in addition to hostile beliefs that both serve to perpetuate patriarchal systems. Participants (N = 490) were currently front-line child welfare workers in the United States who completed an online survey assessing ambivalent sexism and beliefs about father involvement in child welfare cases. Ambivalent sexism was assessed using the Ambivalent Sexism Inventory and the Ambivalence Toward Men Inventory. The Dakota Father Friendly Assessment was modified to assess beliefs about father involvement in child welfare. Latent class analysis was used to empirically derive four sexism profiles. Results indicated that participants with profiles suggesting less sexist beliefs had more positive attitudes about father involvement and had a lower preference for working solely with mothers. Sexism profile was not related to participants’ stated father involvement behaviors such as conducting home visits when fathers are present, including fathers in case planning discussions, and recruiting fathers or paternal relatives as placement options. Implications for social work and child welfare practice include developing training that increases knowledge of fathers’ importance and increases workers’ comfort in providing services to men.

Non-suicidal self-injury (NSSI) is a destructive behaviour engaged in by a large proportion of youth and young adults in current society. Despite previous work, the recent revision of the DSM does not include NSSI as a distinct syndrome; instead it remains in a category for disorders requiring additional research. Thus, in order to better understand the many etiological components underlying NSSI behaviour, still more investigation is required. To this end the current investigations aimed to further elaborate upon known links between NSSI behaviour and parent-child relationships from two perspectives: first, with regard to the overall quality of relationships with parents, and second, with specific focus on the impact of attachment representations of early relationships with parents. Though both perspectives have been investigated in the past, the current studies were developed to alleviate methodological limitations of the existing literature. Study 1 adopted a person-centered approach to examine patterns of perceived relationship quality reported by self-injuring youth based on the combination of multiple relational characteristics; these patterns were then compared with several indices related to different manifestations of NSSI behaviour. Results show heterogeneity in the perceptions of parent-child relationship quality in self-injurers, such that both negative and positive family backgrounds were implicated in the behaviour. Further analyses demonstrate that the level of risk presented by a self-injuring individual can be differentiated based on perceived quality of parent-child relationship. Study 2 investigated how individuals’ internalized states of mind regarding early attachment experiences are related to NSSI, with particular attention dedicated to the relative influences of child maltreatment and attachment representation. Attachment representations reflecting deficits in emotion regulation (preoccupied, unresolved/cannot classify) were most common in self-injurers. Moreover, self-reported childhood maltreatment and attachment states of mind independently contributed to the prediction of NSSI. Lastly, findings suggest that distinct relational influences characteristic of relationships with mothers and fathers are associated with NSSI. The two studies presented here significantly contribute to existing knowledge concerning parental influences in the etiology of NSSI. These investigations add to existing knowledge of NSSI, and may ultimately aid in preventing and treating this damaging behaviour.

In this thesis we present novel methods for constructing and fitting 2d models of shape and appearance which are used for analysing human faces. The first contribution builds on previous work on discriminative fitting strategies for active appearance models (AAMs) in which regression models are trained to predict the location of shapes based on texture samples. In particular, we investigate non-parametric regression methods including random forests and Gaussian processes which are used together with gradient-like features for shape model fitting. We then develop two training algorithms which combine such models into sequences, and systematically compare their performance to existing linear generative AAM algorithms. Inspired by the performance of the Gaussian process-based regression methods, we investigate a group of non-linear latent variable models known as Gaussian process latent variable models (GPLVM). We discuss how such models may be used to develop a generative active appearance model algorithm whose texture model component is non-linear, and show how this leads to lower-dimensional models which are capable of generating more natural-looking images of faces when compared to equivalent linear models. We conclude by describing a novel supervised non-linear latent variable model based on Gaussian processes which we apply to the problem of recognising emotions from facial expressions.

Background: Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) is an urgent public health issue in Mexico. Mexico has witnessed a 122% increase in reported prevalence of HIV since 2001 (Holtz et al., 2014). Country estimates suggest there are between 140,000-230,000 individuals living with HIV in Mexico (CENSIDA, 2014). While approximately 50% of individuals living with HIV in Mexico are unaware that they are living with the virus (CENSIDA, 2014). Despite a federal universal HIV program implemented in 2011, HIV in Mexico has not reached a chronic infectious disease status as seen in other regions of the globe (Deeks, 2013). The mortality rate among individuals with HIV/AIDS in Mexico is 4.2 per 100,000 (CENSIDA, 2014). There is a paucity of findings regarding social and epidemiological data focused on populations outside traditional at risk populations of HIV in Mexico (Martin-Onraët et al., 2016). Analyzing aggregate country level data for Mexico provides necessary insights to better understanding previously unconsidered social factors that are informing sexual and reproductive health trends influencing HIV health patterns. Methods: Secondary analyses were performed on Mexico's Encuesta Nacional de Salud y Nutrición 2012 (ENSANUT). Mexico’s ENSANUT is a probabilistic aggregate national dataset with a multistage stratified cluster sampling design (Janssen et al., 2013). ENSANUT is Mexico’s equivalent to the National Health and Nutrition Examination Survey (NHANES) in the United States. Data is collected via self-report interviews conducted at the participant's home. A structured questionnaire was administered to individuals 20 years of age and older (≥ 20) where sexual and reproductive data was collected from participants. The ENSANUT adult study sub-sample (n=46,227) is comprised of 42.75% men and 57.25% women. A general linear model (GLM), principal component analysis (PCA), chi-squares (χ²), and logistic regressions were applied to the study adult subsample to disentangle social factors associated with sexually transmitted infections (STIs) in the population. Quantitative analyses were conducted on SAS 9.4. Findings: Men were more likely to have a STI diagnosis (OR=3.60; 95% CI 3.00, 4.32, p=<0.001). Previous HIV testing was found to be protective for STI diagnosis across both genders (OR=0.82, 95% CI 0.72, 0.94, p=<0.001). Co-infections of HIV/gonorrhea and HIV/syphilis (n=20) were the highest in the study population. The latent variable model indicates mental health and access to health care resources are critical for positive sexual and reproductive health outcomes in Mexico. Mental health was found to be non-protective for STI risk among the study population (OR=1.59, 95% CI 1.41, 1.81, p=<0.0001). Policy recommendations: 1. Increased access and utilization of HIV resources and mental health services would benefit the study population. Further qualitative research is needed to better understand the barriers to health care access and utilization in these two domains; 2. Increase in preventative programs and health initiatives that encourage established strategies for positive sexual and reproductive health outcomes. These strategies include: universal human papillomavirus (HPV) vaccines, wide availability of Pre-Exposure Prophylaxis (PrEP), and routine HIV/STI screenings; 3. Alternative data collection strategies for ENSANUT which are culturally appropriate for sexual and reproductive health constructs.

Bakgrund: Barnmorskans bemötande är av stor betydelse för kvinnans upplevelse av att känna sig trygg och hantera smärtan under latensfasen och förlossningen. Målet är att kvinnan ska vara hemma under latensfasen då sjukhusmiljön kan ha en negativ inverkan på det fysiologiska förlossningsförloppet. Mödrahälsovården har en viktig roll genom att stötta och förbereda den gravida kvinnan inför förlossningen. Syfte: Att undersöka kvinnors upplevelse av att under latensfasen sökt vård på förlossningsavdelningen och sedan fått åka hem. Metod: En kvalitativ intervjustudie har gjorts och baseras på fem enskilda intervjuer med förstföderskor. Datamaterialet analyserades enligt innehållsanalys. Resultat: Kvinnorna kände sig oförberedda och uttryckte en okunskap om latensfasen. Bemötandet från barnmorskan på förlossningen var av betydelse för hur kvinnorna upplevde och kunde hantera latensfasen och förlossningen. Smärtsamma förvärkar och sömnbrist var de huvudfaktorer som gjorde att de besökte förlossningen. Slutsats: Studien visade att  informationen från barnmorskan på mödrahälsovården gällande latensfasen var bristfällig och behöver förbättras. Kvinnorna hade svårt att avgöra när de var i aktiv fas och skulle åka in till förlossningen. Barnmorskan på förlossningen behöver se den enskilda kvinnan och anpassa omhändertagandet individuellt. Även partner/närstående kan vara i behov av råd och stöd från barnmorskan för att lättare kunna hjälpa kvinnan under latensfasen. / Background: The midwife's attitudes are important for a woman’s experience of feeling secure and manage pain during latent phase and delivery. The goal is that the woman should be at home during latent phase, because of that the hospital environment can have a negative impact on the physiological delivery process during this phase. Maternal health care has an important role by supporting and preparing the pregnant woman for birth. Objective: To explore women's experiences of latent phase, sought care at the maternity ward, and then had to go home. Method: A qualitative study has been done and is based on five individual interviews with first-time mothers. The data were analyzed according to content analysis. Results: The women felt unprepared and expressed ignorance about latent phase. The treatment from the midwife at the maternity ward was important for the women and how they could handle their experience of latent phase and delivery. Painful contractions and sleep deprivation were the main factors that made the women visit the maternity ward. Conclusion: The study showed that the information about latent phase from the midwife at the maternal health care center was inadequate and need improvement. The women found it  difficult to determine when they were in active phase and would go into the maternity ward. The midwife at the maternity ward need to see the individual woman and adapt care individually. Partners / relatives may be in need of advice and support from the midwife to make it easier to help the woman in latent phase.

While pragmatics, through its integration of situational awareness and real world relevant knowledge, offers a high level of analysis that is suitable for real interpretation of natural dialogue, semantics, on the other end, represents a lower yet more tractable and affordable linguistic level of analysis using current technologies. Generally, the understanding of semantic meaning in literature has revolved around the famous quote ``You shall know a word by the company it keeps''. In this thesis we investigate the role of context constituents in decoding the semantic meaning of the engulfing context; specifically we probe the role of salient concepts, defined as content-bearing expressions which afford encyclopedic definitions, as a suitable source of semantic clues to an unambiguous interpretation of context. Furthermore, we integrate this world knowledge in building a new and robust unsupervised semantic model and apply it to entail semantic relatedness between textual pairs, whether they are words, sentences or paragraphs. Moreover, we explore the abstraction of semantics across languages and utilize our findings into building a novel multi-lingual semantic relatedness model exploiting information acquired from various languages. We demonstrate the effectiveness and the superiority of our mono-lingual and multi-lingual models through a comprehensive set of evaluations on specialized synthetic datasets for semantic relatedness as well as real world applications such as paraphrase detection and short answer grading. Our work represents a novel approach to integrate world-knowledge into current semantic models and a means to cross the language boundary for a better and more robust semantic relatedness representation, thus opening the door for an improved abstraction of meaning that carries the potential of ultimately imparting understanding of natural language to machines.

Multiyear trends showing high rates of alcohol and opioid-related misuse as well as opioid-related deaths have renewed attention on both access to and the quality of substance use treatment. In response, diverse healthcare systems that care for the Medicaid population have begun implementing large-scale transformations including new services and provider training requirements. The Centers for Medicaid and Medicare Services has urged state Medicaid programs to use Sections 1115 waiver demonstrations as vehicles for substance use treatment delivery system transformation. For many states, undertaking the Section 1115 waiver demonstration means moving from very limited benefits to a full continuum of new services. States’ ability to achieve such transformations is unknown since demonstration processes are under-reported and considered implementation “black boxes”. Substance use treatment delivery changes are also occurring at the community level, where several hospitals systems have implemented new services to meet the needs of their patient population. However, the influence of these new care models on patient service utilization is unknown. In this dissertation, I use comparative case study design and qualitative content analysis to examine the pre-implementation decision-making processes that Medicaid policymakers in California, Virginia and West Virginia experienced when deciding to enhance their substance use treatment service delivery systems using Sections 1115 waivers. I qualitatively describe how broad sociocultural and local organizational factors influenced Medicaid agencies’ ability to expand access to treatment. I also present a taxonomy of implementation strategies used to translate Medicaid policy into clinical services available in the community. Finally, I present a latent transition analysis to reveal how the nature of substance use treatment services available to patients may influence their service utilization over time. This final quantitative analysis is set within the context of a safety net hospital that provides a comprehensive, low barrier access model for substance use treatment, and primarily serves Medicaid beneficiaries. Results of this dissertation illuminate processes and outcomes associated with pre-, mid-, and post-implementation activities targeting improvements in the delivery of substance use treatment services. / 2023-01-19T00:00:00Z