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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.
11

COMPARING PERSONALITY DISORDER MODELS: FFM AND DSM-IV-TR

Samuel, Douglas B. 01 January 2008 (has links)
The current edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR; American Psychiatric Association, 2000) defines personality disorders as categorical entities that are distinct from themselves and from normal personality traits. However, many scientists now believe that personality disorders can best be conceptualized using a dimensional model of traits that span normal and abnormal personality, such as the Five-Factor Model (FFM). Many research studies have indicated that the current personality disorder system can be adequately conceptualized using the FFM. However, if the FFM or any dimensional model is to be considered as a credible alternative to the current model, it must first demonstrate an increment in the validity of the assessment offered within a clinical setting. Thus, the current study extended previous research by comparing the convergent and discriminant validity of the current DSM-IV-TR model to the FFM across four assessment methodologies. Eighty-eight individuals that were currently receiving ongoing psychotherapy were assessed for the FFM and the DSM-IV-TR personality disorders using self-report, informant report, structured interview, and therapist ratings. The results indicated that the FFM had an appreciable advantage over the DSM-IV-TR in terms of discriminant validity and, at the domain level, convergent validity. Implications of the findings for future research are discussed.
12

Gravity anomalies, flexure and the thermo-mechanical evolution of the West Iberia Margin and its conjugate of Newfoundland

Cunha, Tiago January 2008 (has links)
The West Iberia (WIM) and Newfoundland (NFM) continental margins formed over a succession of rift events related to the opening of the North Atlantic between the Late Triassic and the Early Cretaceous. They are characterized by a variable width Ocean- Continent Transition (Zone) where exhumed and serpentinized mantle has been cored. Results from 1-D well backstripping along the Portuguese shelf suggest 40-45% greater extension factors (β) than previous estimates. In addition, the age and duration of both the Late Triassic-earliest Jurassic and the Late Jurassic rifting episodes have been better constrained. It appears, for example, that the Late Jurassic rift propagates northwards along the margin, as inferred for the continental break-up during the Early Cretaceous. Combined backstripping and gravity modelling techniques (POGM), together with new bathymetry and sediment thickness grids, have been used to estimate the effective elastic thickness, T<sub>e</sub>, of the lithosphere. Results along closely space profiles in the WIM reveal that T<sub>e</sub> decreases from 15-40 km over unthinned Variscan basement to ≤ 15 km over stretched continental and transitional crust. Along strike, a good correlation is found between the modelled mechanical structure and the segmentation of the Variscan basement onshore. Discrepancies between observed and calculated anomalies are discussed in terms of other processes that affected the margin, such as serpentinization and inversion. Thermo-mechanical rheological modelling techniques have also been tested. The compiled software inputs the β's constrained from POGM to determine the thermal structure of the margin, which, in turn, has been used to construct models of rheology and, hence, T<sub>e</sub>. The models predict an increase in the T<sub>e</sub> of thinned continental lithosphere with age since rifting, between < 20 and > 35 km, and suggest that processes such as ductile shearing and mantle serpentinization might have permanently weakened the lithosphere. Results from POGM along conjugate profiles off WI and NF reveal a greater longterm strength of extended continental and transitional basement in the NFM (T<sub>e</sub>'s of 10-40 km). This analysis further supports the hypothesis that the low T<sub>e</sub>'s modelled in the WIM might be related to its complex structural framework. In order to explain the large asymmetries observed in the amount of basement subsidence (500-1300 in) between the WI and NF margins a lithospheric-scale "simple shear" rift model is proposed for the latest stages of rifting and continental break-up.
13

Norrislide: Convergent Total Synthesis and Preliminary Biological Investigations

Granger, Krista Elizabeth January 2009 (has links)
Thesis advisor: Marc L. Snapper / Chapter 1: A review of Shapiro reactions as a coupling strategy in natural product total synthesis. The syntheses of lycoramine, galanthamine, yuehchukene analogues, ovalicin, studies toward the ingenol core, haemanthidine, pretazettine, tazettine, crinamine, Taxol, colombiasin A, elisapterosin B, the AB ring fragment of spongistatin 1 and 8-epipuupewhedione are discussed. Chapter 2: The convergent total synthesis of the marine natural product norrisolide is described. Both subunits, the hydrindane core and the norrisane side chain, are prepared in an asymmetric fashion through kinetic resolution and enantioselective cyclopropanation, respectively. A Shapiro reaction couples the two fragments and a Peterson olefination installs the 1,1-disubstituted olefin. Chapter 3: Preliminary experiments to isolate the biological target of norrisolide through reductive alkylation and tritium labeling are investigated. Further experiments are proposed to shed light on the primary norrisolide-protein interactions. / Thesis (PhD) — Boston College, 2009. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.
14

CONVERGENT VALIDITY OF A BRIEF AND LONG TEMPORAL DISCOUNTING SURVEY

Yeggy, Maria 01 December 2018 (has links)
Temporal discounting can be used to evaluate impulsivity in various populations. One assessment measure that can be used is a monetary choice questionnaire in which individuals are provided with an option to select a specified amount of money now, or a different amount following a temporal delay. This study examines the convergent validity of a long monetary choice questionnaire consisting of 189 questions and a brief monetary choice questionnaire consisting of 7 questions, in which participants can select all of the amounts they would prefer to acquire. The results of this study suggested that there is convergent validity between the two surveys through the use of Pearson’s correlation (r=.648, p< .001) and a paired samples t- test that demonstrated that the difference between the AUC scores was not significant (p=.287). Keywords: discounting, convergent validity, impulsivity, self- control, temporal discounting
15

The Open-Closed Cognitive Dimension and Divergent-Convergent Abilities

Uhes, Michael J. 01 May 1968 (has links)
The relationship between level of dogmatism and divergent-convergent abilities was investigated in a sample of high school subjects. Rokeach's Dogmatism Scale, Form E, and tests of divergent and convergent ability were administered to all subjects. On the basis of their performance on the Dogmatism Scale, three experimental groups were formed: high, medium , and low dogmatics. An analysis of the data showed dogmatism to be negatively correlated with originality, flexibility, composite divergent and composite convergent scores. Fluency was the only ability not negatively correlated with dogmatism. High dogmatic subjects performed convergent operations better than they performed divergent operations, while low dogmatic subjects performed both operations equally well.
16

Developmental and Genetic Mechanisms of Ovariole Number Evolution in Drosophila

Green, Delbert Andre 06 June 2014 (has links)
The goal of the "Quantitative Trait Gene" (QTG) program is to identify genes and mutations that underlie natural phenotypic variation. My goal with this work was to contribute an additional model to the program: ovariole number evolution in Drosophila. In this thesis I describe the progress I have made towards identifying a specific genetic change that contributed to the divergence of ovariole number between two Drosophila lineages. I identify specific developmental mechanisms relevant to establishing ovariole number in different Drosophila lineages by detailing ovarian cell-type specific specification, proliferation, and differentiation. I test specific candidates of genetic regulators of these developmental mechanisms with mutational analysis in D. melanogaster. I show that independent evolution of ovariole number has resulted from changes in distinct developmental mechanisms, each of which may have a different underlying genetic basis in Drosophila. I use the interspecies comparison of D. melanogaster versus D. sechellia to test for functional differences in insulin/insulin-like growth factor (IIS) signaling between the two species. I show that IIS activity levels and sensitivity have diverged between species, leading to both species-specific ovariole number and species-specific nutritional plasticity in ovariole number. Moreover, plastic range of ovariole number correlates with ecological niche, suggesting that the degree of nutritional plasticity may be an adaptive trait. My work and quantitative genetic analyses strongly support the hypothesis that evolution of the Drosophila insulin-like receptor (InR) gene, specifically, is at least partially responsible for the divergence in ovariole number and nutritional plasticity of ovariole number between D. melanogaster and D. sechellia. I detail ongoing experiments to test this hypothesis explicitly via cross-species transgenesis.
17

Evolution Revolution

Vice President Research, Office of the 11 1900 (has links)
His world is full of organisms with no names. Brian Leander is working to discover and characterize the diversity of life on Earth.
18

Conifer Evolution, from Demography and Local Adaptation to Evolutionary Rates : Examples from the Picea genus

Chen, Jun January 2012 (has links)
Evolutionary process can be inferred at three different levels: the species level, the population level and the molecular level. In this thesis, I applied approaches at these three levels and aimed to get a comprehensive picture of conifer evolution, from speciation and demography to geographic variation and local adaptation, and then to the molecular evolution of proteins and small regulatory RNAs. Spruce species have been observed to possess a large number of trans-species shared polymorphisms. Using an “Isolation with migration” model, we found that the large effective population size of spruce retained these shared polymorphisms, inheriting them from the common ancestor. Post-divergence gene flow only existed between Picea abies and P. glauca, and between P. wilsonii and P. schrenkiana. The combination of Tajima’s D and Fay &amp; Wu’s H at most of loci suggested an ancient and severe bottleneck for most species except P. breweriana. Furthermore, I investigated the effect of local selection in two parallel clines, which is one of the major forces that can cause divergence or even speciation. The timing of bud set and growth cessation was found correlated with latitude in populations of P. abies and P. obovata. Using allele frequency spectrum analyses we identified three genes under local selection in both species including two circadian-clock genes GI and PRR7, and one photoperiodic gene FTL2. This indicated that parallel evolution could occur through groups of genes within related pathways. Clinal variation at expression level provided stronger evidence of selection in FTL2, which has previously been associated with bud set in P. abies. Finally we focused on the molecular evolution of mRNA and small regulatory RNAs in P. abies. With the help of Next-Generation sequencing, we have achieved in spruce the first de novel assembly of the needle transcriptome and a preliminary characterization of sRNA populations. Along with features common in plants, spruce also exhibited novelties in many aspects including lower substitution rate and protein evolutionary rate, dominance of 21-nt sRNA, and a large proportion of TIR-NBS-LRR genes as sRNA sources and targets.
19

Uplift in response to tectonic convergence : the Kyrgyz Tien Shan and Cascadia subduction zone /

Burgette, Reed Joel. January 2008 (has links)
Thesis (Ph. D.)--University of Oregon, 2008. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 225-242). Also available online in ProQuest, free to University of Oregon users.
20

Understanding convergent innovation in healthcare technologies : relational models for nascent ecosystems

Phillips, Mark Alwyn January 2018 (has links)
New developments such as 'Precision Medicine' and 'Digital Health' are emerging areas in healthcare technology, underpinned by 'convergent technology' or 'cross-industry' innovation. However, convergence results in greater uncertainty and influence from new knowledge and actors, including previously disparate technologies and capabilities, bringing specific challenges in the development of innovations. Although the literature addresses the context of technology convergence, there has been limited research reported on the how such innovation is effected in nascent ecosystems. This qualitative research addresses identified literature gaps, initially by using a combination of ecosystem actor interviews (n=39) to understand the context, followed by five longitudinal in-depth case studies at innovator organisations. Case evidence was obtained from a combination of interviews (n=62), supplemented by field observations, primary documents and evidence from publicly available sources. The data was subjected to multiple coding methods, with plausible causal mechanisms identified through case and cross-case analyses. The research findings identify a set of five interconnected micro-processes (early organisational routines) which together form a non-deterministic activity system that enables an innovator to navigate (the ecosystem), negotiate (a position within it) and nurture (the innovation and ecosystem). The research further identifies the importance of careful balancing between relationally focussed credibility-seeking and advantage-seeking actions as the main driver 'guiding' managers when developing the innovation, the associated business model(s) and value network in the evolving ecosystem. A conceptual model and framework are developed to show the interrelationships between organisational routines, the activity systems and the ecosystem. In developing organisational capabilities, it is argued that convergent innovation requires mostly incremental changes (low depth of change) across many organisational routines (high breadth of change), which reduce the uncertainty of organizational change and thus increase internal acceptance. These findings support the argument that innovators require a more 'systemic' view of innovation and governance approaches contributing to the innovation and capabilities literature. From a practice perspective, the research provides mechanisms for building relational capabilities critical to innovation delivery.

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