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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Investigando o crescimento proveniente do enfrentamento de adversidades : evidências de validade da versão brasileira do inventário de crescimento pós-traumático

Campos, João Oliveira Cavalcante January 2017 (has links)
Crescimento pós-traumático (CPT) refere-se à mudança positiva em algum aspecto da experiência humana como resultado do enfrentamento de situações adversas (traumáticas ou crises de vida em geral). O objetivo geral do presente trabalho foi investigar em uma amostra brasileira as propriedades psicométricas da Versão Brasileira do Inventário de Crescimento Pós-Traumático (Brazilian Version of the Posttraumatic Growth Inventory – PTGI-B), instrumento que se propõe a mensurar CPT. Para isso, dois estudos distintos foram realizados. O Estudo I buscou investigar a estrutural fatorial do PTGI-B. Participaram dele 321 pessoas que passaram por situações adversas variadas. A estrutura fatorial do PTGI-B foi investigada através do método de análise fatorial confirmatória. Testou-se cinco diferentes modelos de estrutura fatorial. A estrutura convencional de cinco fatores apresentou melhores índices de ajuste quando comparada às demais. Além disso, o modelo de cinco fatores de primeira ordem organizados em torno de um fator geral de segunda ordem também mostrou índices de ajuste adequados. O Estudo II buscou avaliar se as evidências de validade externa da Versão Brasileira do Inventário de Crescimento Pós-Traumático (PTGI-B) são mais consistentes quando se compara os resultados de um subgrupo pontuou alto na Escala de Centralidade de Eventos (ECE) versus os resultados do subgrupo que pontuou baixo na ECE - que avalia em que medida o evento de referência contribuiu na formação da identidade dos indivíduos. Participaram do estudo 317 pessoas que passaram por situações adversas variadas. Investigou-se a relação entre crescimento pós-traumático, suporte social, sentido de vida, satisfação com a vida, religiosidade e desajuste psicológico. As correlações entre CPT e as demais variáveis de interesse mostraram-se maiores e mais coerentes no subgrupo que pontuou alto na ECE do que no subgrupo que pontuou baixo. Os resultados obtidos fortalecem a concepção de que apenas eventos que levam a uma reavaliação das crenças centrais dos indivíduos devem ser incluídos nos estudos de CPT. / Posttraumatic growth (PTG) refers to the positive change in some aspect of the human experience as a result of facing adverse situations (traumatic or general life crisis). The main goal of the present study was to investigate the psychometric properties of the Brazilian Version of the Posttraumatic Growth Inventory (PTGI-B). To address this purpose, two distinct studies were performed. Study I was aimed to investigate the factor structure of the PTGI-B. It involved 321 people who had been through a wide range of adverse situations. The factorial structure of the PTGI was investigated using the method of confirmatory factorial analysis. Five different models of factorial structure were tested. The conventional five factor structure presented better adjustment indices when compared to the others. However, the factorial structure of five first order factors organized around a second order global PTG factor was also adequate. Study II intended to assess whether evidence of the external validity of the Brazilian Version of the Post Traumatic Growth Inventory (PTGI-B) is more consistent when considering the events in which individuals scored high versus individuals who scored low on the Centrality of Events Scale (ECE). The ECE assesses to what extent the reference event contributed to the formation of individuals' identity. A total of 317 people who had been through a variety of adverse events participated in the study. It was investigated the relationship between posttraumatic growth, social support, meaning in life, life satisfaction, religiosity and psychological distress. The correlations between PTGI-B scores and the other variables of interest became larger and more theoretically coherent in the subgroup that scored high in ECE than in the subgroup that scored low. The results obtained strengthen the conception that only events that lead to a reassessment of individuals’ central beliefs should be included in the PTG studies.
22

Development of a Self-Report Measure of Post-Traumatic Stress Disorder (PTSD) and Complex PTSD (CPTSD) According to the Eleventh Edition of the International Classification of Diseases (ICD-11): The Complex Trauma Inventory

Litvin, Justin M. 08 1900 (has links)
The work group editing trauma disorders for the upcoming edition of the International Classification of Diseases (ICD-11) made several changes. Specifically, they significantly simplified the guidelines for post-traumatic stress disorder (PTSD) and added a new trauma disorder called complex PTSD (CPTSD). The new domains for PTSD and the addition of CPTSD require new instruments to assess these novel constructs. We developed a measure of PTSD and CPTSD (Complex Trauma Inventory; CTI) according to the proposed ICD-11 domains, creating several items to assess each domain. We examined the factor structure of the CTI (using both exploratory and confirmatory factor analyses) in two separate samples of diverse college students (n1 = 501; n2 = 500), reducing the original 53 trauma items in the item pool to 21 items. Confirmatory factor analyses supported two highly-correlated second-order factors (PTSD and complex factors), with PTSD (i.e., re-experiencing, avoidance, hyper-arousal) and complex factors (i.e., affect dysregulation, alterations in self-perception and alterations in relationships with others) each loading on three of the six ICD-11-consistent first-order factors (RMSEA = .08, CFI = .92, GFI = .87, SRMR = .06). Internal consistency for PTSD (α = .92) and complex factors (α = .93) are excellent.
23

A second-order factor structure of the leadership behaviour inventory

Durrheim, Zenita Beth 30 April 2008 (has links)
A need for a South African leadership-unit performance structural model, created from the performance index and second-order factor structure of the Leadership Behaviour Inventory was established. This study focuses on the creation of such a second-order factor structure. Theron and Spangenberg (2005) identified three plausible models and highlighted two for further analysis. Theoretical scrutiny supported the two proposed models. The two-factor model was created from the multifactor leadership questionnaire's transformational and transactional second-order factors (Avolio, Bass & Jung, 1999) and the three-factor model comprised the general leadership, management behaviour and supervisory leadership second-order factors of House (1995). Factor analysis, exploratory factor analysis and confirmatory factor analysis were conducted on the proposed models. Results indicated average-fitting models. The five-factor model proposed by Theron and Spangenberg (2005) comparatively has an improved fit and is viewed as the most plausible model for the creation of the leadership-unit performance structural model. / Psychology / M.A. (Psychology)
24

Estrutura Fatorial do WISC-III em crianças com dificuldades de aprendizagem: uma validação em amostra brasileira / FACTOR STRUCTURE OF THE WISC-III FOR CHILDREN WITH LEARNING DISABILITIES: A BRAZILIAN VALIDATION

Vidal, Francisco Antonio Soto 30 April 2010 (has links)
Made available in DSpace on 2016-03-22T17:26:22Z (GMT). No. of bitstreams: 1 Francisco Antonio Soto Vidal.pdf: 467609 bytes, checksum: 1074dd1abd43689b74cb26d93afc7e10 (MD5) Previous issue date: 2010-04-30 / The adaptation of a psychological instrument to another cultural environment requires that its rules, validity and reliability be revised. Although the WISC-III has already been adapted to the Brazilian context, further studies on the verification of its construction validity should be performed when used in clinical groups. This work contributes to this research and to the investigation of a factorial model that is more appropriate for Brazilian children with learning disabilities (LD). An amount of 263 WISC-III test protocols performed in public school students referred by their teachers by having difficulties in reading, writing and/or arithmetic after a psychological evaluation were analyzed. Statistical techniques of Exploratory Factor Analysis and Confirmatory Factor Analysis were performed. This study, besides corroborating the factor structure defined in the Brazilian standardization, meets the results of the international research for the definition of four-factor model as the best adjusting for the LD population. Although we also have identified two three-factor models as advantageous as to the fit, parsimony and theoretical interpretability, the four-factorial structure is the most suitable for clinical interpretation of the scores that express the AD group cognitive abilities, since it allows us to leverage existing standards of WISC -III for the general population / A adaptação de um instrumento psicológico a outro meio cultural requer que sejam revisadas suas normas, sua validade e sua fidedignidade. Apesar de o WISC-III já ter sido adaptado ao contexto brasileiro, novos estudos sobre a verificação de sua validade de construto devem realizar-se quando utilizado em grupos clínicos. Este trabalho contribui a essa pesquisa e à investigação do modelo fatorial mais adequado para crianças brasileiras com dificuldades de aprendizagem (DA). Foram analisados 263 protocolos do teste WISC-III de alunos de escolas públicas encaminhados por seus professores para avaliação psicológica por apresentarem dificuldades em leitura, escrita e/ou aritmética. Foram utilizadas as técnicas estatísticas da Análise Fatorial Exploratória e da Análise Fatorial Confirmatória. O presente estudo, além de corroborar a estrutura fatorial definida na padronização brasileira, vai ao encontro dos resultados da pesquisa internacional quanto à definição do modelo de quatro fatores como o de melhor ajuste para o grupo clínico DA. Apesar de também ter identificado dois modelos trifatoriais como vantajosos quanto ao ajuste, parcimônia e interpretabilidade teórica, a estrutura quadrifatorial é a mais indicada para interpretar clinicamente as pontuações que expressam as habilidades cognitivas do grupo DA, uma vez que permite aproveitar as normas existentes do WISC-III para a população geral
25

Investigating the effects of host factors (proteins and non-proteins) on mycobacteria

Riaz, Muhammad Suleman January 2018 (has links)
Mycobacterium tuberculosis (M.tb), the causative agent of tuberculosis, is one of the leading causes of death due to a single infectious agent and results in more than 1 million human deaths every year. M.tb infection of the host initiates a local inflammatory response, resulting in the migration of a number of host plasma protein and non-protein factors to the site of infection. In addition, some of these factors are also produced locally at the site of infection. It is envisaged that these host factors are likely to come in direct contact with M.tb and immune cells and may modulate the outcome of the infection. In this study, a number of host factors including transferrin, lactoferrin, fibrinogen, C-reactive protein, alpha-2-macroglobulin (α2M), vitronectin, plasminogen, low-density lipoprotein (LDL), high-density lipoprotein (HDL), serotonin, L-alpha dipalmitoyl phosphatidylcholine (DPPC) and platelet activating factor C-16 (PAF C-16) were screened in vitro for their direct effect on the growth of mycobacteria using M.smegmatis as a model. As a result of this screening, PAF C-16, a phospholipid compound was identified that directly inhibited the growth of M.smegmatis and M.bovis BCG in a dose and time-dependent manner. Use of a range of PAF C-16 structural analogues, including Lyso-PAF, PAF C-18, Hexanolamino PAF, 2-O-methyl PAF & Pyrrolidino PAF, revealed that small modifications in structure did not alter the direct growth inhibition property of PAF C-16 and similar levels of M.smegmatis and M.bovis BCG growth inhibition were observed as compared to PAF C-16. Structural dissection of PAF C-16 suggested that the attachment of carbon tail to the glycerol backbone via ether bond at sn-1 position was important for its direct growth inhibition activity against mycobacteria. Microscopy and flow cytometry with PAF C-16 treated M.smegmatis and M.bovis BCG showed damage to the bacterial cell membrane. The addition of membrane-stabilizing agents, α-tocopherol, tween-80 and tween-20, partially mitigated the growth inhibitory effect of PAF C-16. These results suggested that the growth inhibition activity of PAF C-16 against mycobacteria is most likely due to its detergent-like effect, resulting in damage to the bacterial cell membrane. PAF C-16 and its structural analogues were also investigated for their effect on the growth of intracellular M.smegmatis inside THP1 cells. In vitro, PAF C-16, PAF C-18 and Hexanolamino PAF inhibited the growth of intracellular M.smegmatis, whereas, analogues such as Lyso-PAF and 2-O-methyl PAF failed to show any growth inhibitory effect, suggesting that the presence of acetyl group at sn-2 position was important for growth inhibition of intracellular M.smegmatis. Use of PAF receptor antagonists partially mitigated the inhibitory effect of PAF C-16 on the growth of intracellular M.smegmatis, suggesting this inhibition was through receptor-mediated signalling pathways. Blocking of PAF C-16 signalling pathway components such as phospholipase C and phospholipase A2, resulted in the increased survival of intracellular M.smegmatis. Arachidonic acid, a product of PAF C-16 signalling pathway directly inhibited the growth of M.smegmatis. Furthermore, inhibition of iNOS enzyme and antibody-mediated neutralization of TNF-α partially mitigated the inhibitory effect of PAF C-16 on intracellular M.smegmatis growth, suggesting that the production of NO and TNF-α were also involved in PAF C-16 induced intracellular growth inhibition. Overall, this study has identified PAF C-16, its structural analogues such as Lyso-PAF, PAF C-18, Hexanolamino PAF and other compounds including 1-O-hexadecyl-sn-glycerol, miltefosine and hexadecyl lactate with novel anti-mycobacterial activity. Further investigations are needed to demonstrate their effectiveness against M.tb both in vitro and in animal models to assess their therapeutic potential as anti-TB drugs.
26

Validation of the Questionnaire for Eudaimonic Well-being in a South African context / L. Boshoff

Boshoff, Lusilda, 1985- January 2012 (has links)
Explicating the nature and concomitants of eudaimonic well-being is currently at the forefront of research on a fulfilling life and functioning well. However, the strength of research conducted on constructs is dependent on the quality of instrumentation. In view of this notion, Waterman et al. (2010) developed the Questionnaire for Eudaimonic Well-Being (QEWB) to operationalise their conceptualisation of eudaimonic well-being and explored the scale’s validity in American student samples. In particular, they confirmed a good fit of a unidimensional factor structure by using parcelled indicators in confirmatory factor analysis. Research on the applicability of this measure within the other cultural contexts needs to take cognisance of aspects such as conceptual equivalence, translation issues, and validity criteria. To contribute to the adaptation of the QEWB for the multilingual South African context, the aim of this study was to explore the structural and external validity of English, Afrikaans, and Setswana versions of the QEWB. A cross-sectional questionnaire survey design was used for data gathering. The sample (n = 975) consisted of students from a large university in South Africa, who completed either the English (n = 325), Afrikaans (n = 478), or Setswana (n = 172) version of the scale. To investigate the structural validity of the scale, descriptive statistics, reliability coefficients, and the scale’s factor structure were scrutinised. Regarding the latter, confirmatory factor analyses with both parcel- and item-level indicators, as well as principal component analyses were examined to assess the fit of a one-factor model. Exploratory factor analyses were conducted to further explore the dimensionality of the scale. External validity was examined by considering the attenuation corrected correlational patterns between scores on the QEWB and measures of well-being and ill-being. Results showed that item- and scale-level scores were mostly negatively skewed, with high average scores. Internal consistency reliability statistics indicated satisfactory reliability, except for a small mean interitem correlation for the Setswana instrument. Although adequate goodness of fit statistics of parcel-level confirmatory factor analyses supported Waterman et al.’s (2010) notion of a one-factor structure, the assumption of unidimensionality within parcels was not satisfied, which suggested that these analyses could have masked multidimensionality. A lack of fit of the one-factor model was shown by a number of small or negative interitem and item-total correlations, insufficient fit indices for item-level confirmatory factor analyses, and a small proportion of variance explained by the first unrotated component in principal component analysis. Exploratory factor analyses indicated a three-factor model, where the factors Sense of Purpose, Active Involvement in Beliefs, and Effortful Engagement were distinguished. For the English scale, a four-factor model was also sensible. Items that may need modification for the current context were identified. Support for convergent and discriminant validity was established. This study contributed to a further validation of the QEWB and highlighted its multidimensional structure for the groups involved. Further evaluation of the scale on conceptual and empirical levels is indicated, also specifically for applicability within the South African multilingual context. / Thesis (MSc (Clinical Psychology)--North-West University, Potchefstroom Campus, 2013.
27

Validation of the Questionnaire for Eudaimonic Well-being in a South African context / L. Boshoff

Boshoff, Lusilda, 1985- January 2012 (has links)
Explicating the nature and concomitants of eudaimonic well-being is currently at the forefront of research on a fulfilling life and functioning well. However, the strength of research conducted on constructs is dependent on the quality of instrumentation. In view of this notion, Waterman et al. (2010) developed the Questionnaire for Eudaimonic Well-Being (QEWB) to operationalise their conceptualisation of eudaimonic well-being and explored the scale’s validity in American student samples. In particular, they confirmed a good fit of a unidimensional factor structure by using parcelled indicators in confirmatory factor analysis. Research on the applicability of this measure within the other cultural contexts needs to take cognisance of aspects such as conceptual equivalence, translation issues, and validity criteria. To contribute to the adaptation of the QEWB for the multilingual South African context, the aim of this study was to explore the structural and external validity of English, Afrikaans, and Setswana versions of the QEWB. A cross-sectional questionnaire survey design was used for data gathering. The sample (n = 975) consisted of students from a large university in South Africa, who completed either the English (n = 325), Afrikaans (n = 478), or Setswana (n = 172) version of the scale. To investigate the structural validity of the scale, descriptive statistics, reliability coefficients, and the scale’s factor structure were scrutinised. Regarding the latter, confirmatory factor analyses with both parcel- and item-level indicators, as well as principal component analyses were examined to assess the fit of a one-factor model. Exploratory factor analyses were conducted to further explore the dimensionality of the scale. External validity was examined by considering the attenuation corrected correlational patterns between scores on the QEWB and measures of well-being and ill-being. Results showed that item- and scale-level scores were mostly negatively skewed, with high average scores. Internal consistency reliability statistics indicated satisfactory reliability, except for a small mean interitem correlation for the Setswana instrument. Although adequate goodness of fit statistics of parcel-level confirmatory factor analyses supported Waterman et al.’s (2010) notion of a one-factor structure, the assumption of unidimensionality within parcels was not satisfied, which suggested that these analyses could have masked multidimensionality. A lack of fit of the one-factor model was shown by a number of small or negative interitem and item-total correlations, insufficient fit indices for item-level confirmatory factor analyses, and a small proportion of variance explained by the first unrotated component in principal component analysis. Exploratory factor analyses indicated a three-factor model, where the factors Sense of Purpose, Active Involvement in Beliefs, and Effortful Engagement were distinguished. For the English scale, a four-factor model was also sensible. Items that may need modification for the current context were identified. Support for convergent and discriminant validity was established. This study contributed to a further validation of the QEWB and highlighted its multidimensional structure for the groups involved. Further evaluation of the scale on conceptual and empirical levels is indicated, also specifically for applicability within the South African multilingual context. / Thesis (MSc (Clinical Psychology)--North-West University, Potchefstroom Campus, 2013.
28

Emotion experience, emotional intelligence and well-being in South Africa / Nadia Botma

Botma, Nadia January 2009 (has links)
Thesis (Ph.D. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2010.
29

Emotion experience, emotional intelligence and well-being in South Africa / Nadia Botma

Botma, Nadia January 2009 (has links)
Thesis (Ph.D. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2010.
30

A second-order factor structure of the leadership behaviour inventory

Durrheim, Zenita Beth 30 April 2008 (has links)
A need for a South African leadership-unit performance structural model, created from the performance index and second-order factor structure of the Leadership Behaviour Inventory was established. This study focuses on the creation of such a second-order factor structure. Theron and Spangenberg (2005) identified three plausible models and highlighted two for further analysis. Theoretical scrutiny supported the two proposed models. The two-factor model was created from the multifactor leadership questionnaire's transformational and transactional second-order factors (Avolio, Bass & Jung, 1999) and the three-factor model comprised the general leadership, management behaviour and supervisory leadership second-order factors of House (1995). Factor analysis, exploratory factor analysis and confirmatory factor analysis were conducted on the proposed models. Results indicated average-fitting models. The five-factor model proposed by Theron and Spangenberg (2005) comparatively has an improved fit and is viewed as the most plausible model for the creation of the leadership-unit performance structural model. / Psychology / M.A. (Psychology)

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