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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.
571

Vishet i arbetslivet : En utveckling av ett arbetslivsanpassat vishetsformulär

Lagerholm, Anna January 2014 (has links)
Vishet som fenomen har en lång historia, dock har begreppet under de senaste åren uppmärksammats allt mer av empirisk forskning. Det råder oenigheter kring fenomenets innebörd. Många studier visar dock att vishet kännetecknas av kognitiva och reflekterande dimensioner - precis som i Ardelts teori där vishet förklaras genom kognitiva, affektiva och reflekterande egenskaper. Denna studie utgår från Ardelts teori. En enkätundersökning med 110 deltagare genomfördes med syftet att utforma ett för arbetslivet modifierat vishetsformulär. Dessutom ämnade studien jämföra kön, ålder och privat respektive kommunal sektor. Resultatet visade hög korrelation mellan det modifierade vishetsformuläret (ViA) och Ardelts tredimensionella visdomsskala (3D-WS). Dessutom visade resultatet att privat sektor erhöll signifikant högre poäng än kommunal sektor i 3D-WS, samt att kvinnor i snitt fick högre poäng än män. Åldersskillnader påvisades inte. Studiens brister i form av bland annat representativitet, antalet deltagare och utformningen av enkäten diskuterades.
572

Three dimensional evaluation of the TMJ condyle position in different types of skeletal patterns

Guedes, Ines H. 06 March 2014 (has links)
Objective: To evaluate three-dimensional position of the TMJ condyle within the glenoid fossa in different types of skeletal patterns. Materials and methods: Ninety CBCT images were consecutively selected and divided into skeletal class I, class II and class III. The images were analyzed locating landmarks in the different areas of the condyle and glenoid fossa. All landmarks presented acceptable reliability. The mean results were compared using ANOVA and Bonferroni post-hoc test (p < 0.05). Results: There was a tendency for the anterior joint space to be smaller than the posterior joint space. Statistical analysis, however, evidenced no significant differences between the anterior, superior and posterior joint spaces and the different skeletal patterns or between sides. Conclusion: There was non-concentricity of the condyle for all the groups studied, and no particular direction was statistically significantly favored. It is unclear whether the differences found would be clinically significant, considering anatomical individual variations.
573

From Perseveration to Flexibility: Reflection and the Down-regulation of Conflict Detection Underlying Executive Function Development

Espinet, Stacey 07 August 2013 (has links)
Introduction. Executive function refers to the top-down neurocognitive processes involved in flexible, goal-oriented behavior. A number of studies have shown positive effects of EF training. The overall aim of these studies was to explore the neurocognitive processes that support the development of EF by understanding how EF training works and what the active ingredients are. Particular interest was in isolating the role of reflection in EF training to understand its top-down affect on ACC-mediated conflict detection. Method. In Exp. 1 the neural markers of EF were explored by comparing ERPs of preschoolers who passed the DCCS and preschoolers who failed. Exp. 2 represents an attempt to replicate the key findings of Kloo & Perner, (2003, Exp. 2) that reflection training improves preschoolers’ performance on the DCCS and demonstrates far transfer. A shortened version of the training protocol was also tested (Exp. 3). In Exp. 4, the neural correlates of reflection training in preschoolers were explored by examining changes in the neural marker of EF found in Exp. 1. Results. In Exp. 1, the N2 amplitude was smaller (less negative) for children who passed the DCCS and were able to efficiently resolve the conflict in the stimuli than for children who failed and were unable to resolve the conflict. Exp. 2 replicated the findings of Kloo & Perner, (2003, Exp. 2) even using a brief (15 min) intervention targeting reflection (Exp. 3). In Exp. 4, one brief session of reflection training made children who initially failed the DCCS look like children who initially passed at both the behavioral and neural level (reduced N2 amplitude). Conclusion. Results suggest that reflective processing facilitates the development of EF in young children by teaching them to notice conflict, reflect on it, and formulate rules for resolving it, resulting in the down-regulation of ACC-mediated conflict detection.
574

From Perseveration to Flexibility: Reflection and the Down-regulation of Conflict Detection Underlying Executive Function Development

Espinet, Stacey 07 August 2013 (has links)
Introduction. Executive function refers to the top-down neurocognitive processes involved in flexible, goal-oriented behavior. A number of studies have shown positive effects of EF training. The overall aim of these studies was to explore the neurocognitive processes that support the development of EF by understanding how EF training works and what the active ingredients are. Particular interest was in isolating the role of reflection in EF training to understand its top-down affect on ACC-mediated conflict detection. Method. In Exp. 1 the neural markers of EF were explored by comparing ERPs of preschoolers who passed the DCCS and preschoolers who failed. Exp. 2 represents an attempt to replicate the key findings of Kloo & Perner, (2003, Exp. 2) that reflection training improves preschoolers’ performance on the DCCS and demonstrates far transfer. A shortened version of the training protocol was also tested (Exp. 3). In Exp. 4, the neural correlates of reflection training in preschoolers were explored by examining changes in the neural marker of EF found in Exp. 1. Results. In Exp. 1, the N2 amplitude was smaller (less negative) for children who passed the DCCS and were able to efficiently resolve the conflict in the stimuli than for children who failed and were unable to resolve the conflict. Exp. 2 replicated the findings of Kloo & Perner, (2003, Exp. 2) even using a brief (15 min) intervention targeting reflection (Exp. 3). In Exp. 4, one brief session of reflection training made children who initially failed the DCCS look like children who initially passed at both the behavioral and neural level (reduced N2 amplitude). Conclusion. Results suggest that reflective processing facilitates the development of EF in young children by teaching them to notice conflict, reflect on it, and formulate rules for resolving it, resulting in the down-regulation of ACC-mediated conflict detection.
575

Daugiamačių duomenų aproksimavimas / Approximation of multi-dimensional data

Katinas, Raimondas 16 July 2008 (has links)
Šiais laikais vis daugiau domimasi daugiamačių duomenų aproksimavimo teorija. Daugiamatėje erdvėje aproksimavimo teorija palčiai kur taikoma, pavyzdžiui, skaitinių metodų analizėje, bangų analizėje, signalų apdorojime, įvairiose informacinių technologijų sistemose, kompiuterių grafikoje, astronomijoje, naftos klodų tyrinėjime. Ši sritis viliojanti, nes didelė dalis klasikinės matematikos sunkiai pritaikoma daugiamačiams uždaviniams analizuoti. Taigi senoms problemoms spręsti reikalingi nauji įrankiai. Funkcijų aproksimavimo uždavinių gausu įvairiose matematikos, fizikos ir technikos srityse. Gausu ir jų sprendimų būdų bei metodų. Nesunkiai šie uždaviniai sprendžiami, kai funkcija priklauso nuo vieno ar dviejų kintamųjų. Tačiau realiame gyvenime naudojamos funkcijos turi daug daugiau nežinomųjų. Didėjant kintamųjų skaičiui uždavinio sudėtingumas taip pat auga. Pavyzdžiui, kai funkcija priklauso nuo vieno kintamojo, ją galima pavaizduoti plokštumoje kaip kreivę. Dviejų kintamųjų funkciją atitinka paviršius, nubrėžtas trimatėje erdvėje. Funkcijų, kurios priklauso nuo trijų ir daugiau kintamųjų, vaizdavimas jau sukelia problemų, nes žmogus nebegali suvokti didesnio matumo erdvės. Kadangi trimatę erdvę galima pavaizduoti plokštumoje, manoma, kad panašiu principu keturmatę erdvę galima pavaizduoti trimatėje, o šią vėl plokštumoje. Jei pavyktų sugalvoti tokį metodą, erdvės matumas nebesukeltų problemų. Visgi trijų kintamųjų funkciją bandoma vaizduoti dviem būdais: 1. pateikti... [toliau žr. visą tekstą] / This Master‘s work covers a mathematical analysis system which can visualize multivariate data layers, approximate multi-dimensional functions by polynomials, estimate approximation accuracy and present few the most effective aproximation models. Multivariate approximation theory is an increasingly active research area today. It encompasses a wide range of tools for multivariate approximation such as multi-dimensional splines and finite elements, shift-invariant spaces and radial-basis functions. Approximation theory in the multivariate setting has many applications including numerical analysis, wavelet analysis, signal processing, geographic information systems, computer aided geometric design and computer graphics. The field is fascinating since much of the mathematics of the classical univariate theory does not straightforwardly generalize to the multivariate setting, so new tools are required. Graphs of one variable functions are frequantly displayed as curves, bivariate functions - as contour plots. In generally it is very hard to display or realize function in the multivariate setting. However, some efforts have been made to render functions of precisely three variables. Two obvious approaches suggest themselves: 1. Display a number of cross sections where one of the variables is held constant, or, 2. display contour surfaces where the value of function equals some constant. We will use the first method modification in this Master‘s work. All function variables except... [to full text]
576

Trimačių galerijų šablonų generavimas / Generation of three-dimensional gallery patterns

Zigmantaitė, Danguolė 27 August 2009 (has links)
Šiame darbe apžvelgtos įvairios trimatės galerijos ir jų kūrimo principai. Atlikta programų ir įrankių, skirtų galerijoms kurti, analizė. Atlikta VRML programavimo kalbos galimybių ir jos taikymų trimatės grafikos sistemose analizė. Supažindinama su šablonų generavimo būdais. Atlikta įskiepų, skirtų trimačių galerijų naršyklėse peržiūrai, analizė. Panaudojant ArchiCad projektavimo įrankį ir VRML kalbą, sukurtas trimatis galerijos šablonas. / This paper reviews various three – dimensional galleries and their development principles. There was made an analysis of programmes and tools, which were designed for the creation of galleries. The analysis was also made of VRLM programming language – its options and applications in three–dimensional graphics systems. This work acquaints with methods of template generation. There was made an analysis of plugins, which are intended for the viewing in the browsers of three–dimensional galleries. There was created the three–dimensional template of the gallery, by using ArchiCad and VRML design tool.
577

A rapid method for approximating invariant manifolds of differential equations

Tang, Shouchun (Terry), University of Lethbridge. Faculty of Arts and Science January 2006 (has links)
The Intrinsic Low-Dimensional Manifold (ILDM) has been adopted as an approximation to the slow manifold representing the long-term evolution of a non-linear chemical system. The computation of the slow manifold simplifies the model without sacrificing accuracy because the trajectories are rapidly attracted to it. The ILDM has been shown to be a highly accurate approximation to the manifold when the curvature of the manifold is not too large. An efficient method of calculating an approximation to the slow manifold which may be equivalent to the ILDM is presented. This method, called Functional Equation Truncation (FET). is based on the assumption that the local curvature of the manifold is negligible, resulting in a locally linearized system. This system takes the form of a set of algebraic equations which can be solved for given values of the independent variables. Two-dimensional and three-dimensional models are used to test this method. The approximations to onedimensional slow manifolds computed by FET are quite close to the corresponding ILDMs and those for two-dimensional ones seem to differ from their ILDM counterparts. / vii, 61 leaves ; 29 cm.
578

A Quantum phase trasition in d-wave superconductors and symmetry features of quasi-one-dimensional superconductors

Duncan, R. D. (Richard D.) 05 1900 (has links)
No description available.
579

Study of a non-interacting, nonuniform electron gas in two dimensions

Koivisto, Michael William 08 November 2007 (has links)
The non-interacting, nonuniform electron gas exhibits simplifications in two dimensions, that are of particular interest in the application of density functional theory. The results of linear response theory for an attractive impurity in a two-dimensional gas have been shown to be surprisingly accurate even though there are bound states, and were shown to be exact in the high density limit (Zaremba et al. Phys. Rev. B, 71:125323, 2005 and Zaremba et al. Phys. Rev. Lett., 90(4):046801, 2003). The density resulting from linear response theory and the Thomas-Fermi approximation coincide in the high density limit. As an alternative to linear response theory, the Kirzhnits gradient expansion gives corrections to Thomas-Fermi in gradients of the potential. In two dimensions, all of the gradient corrections vanish at zero temperature, which is a new result presented in this work. We have performed numerical calculations which show that while Thomas-Fermi appears to be a surprisingly accurate approximation in two dimensions, it is not exact. The differences between two and three dimensions that lead to the vanishing of the gradient corrections, however, are of great interest since these may lead to better understanding and simplifications of the corresponding three-dimensional problem. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2007-11-07 09:47:00.316
580

ROLE OF CELL ADHESION MICROENVIRONMENT AND THE SRC/STAT3 AXIS IN AUTOCRINE HGF SIGNALING DURING BREAST TUMOURIGENESIS

Starova, BLERTA 22 September 2008 (has links)
Over-expression of both hepatocyte growth factor (HGF) and its receptor Met frequently occurs in invasive human breast cancer, suggesting that the establishment of an HGF “autocrine loop” may be linked to breast tumour progression. We have recently shown a novel activating function of two signaling molecules, Src tyrosine kinase and the signal transducer and activator of transcription-3 factor (Stat3), on HGF expression in breast epithelial cells. Interestingly, Stat3 is also important in normal breast development,but this function does not require Src. In addition, β1-integrin adhesion occurs minimally in differentiated breast epithelium, but is upregulated during oncogenic progression and is required for transformation by Src. We therefore hypothesize that β1-integrin engagement is necessary for Src/Stat3-dependent activation of HGF transcription and breast tumourigensis. Using specific inhibitors of Src (Dasatinib) and Stat3 (CPA7) we demonstrated that autocrine HGF expression is linked to activation of Src/Stat3 in a malignant breast cell line. Phenotypic reversion (e.g., cell rounding and loss of filopodial extensions) and inhibition of pY705Stat3, HGF and pYMet expression as determined by immunofluorescence was achieved with both inhibitor treatments separately, and a synergistic effect was observed with combined treatment. Furthermore, β-catenin localization was nuclear in malignant cells, but shifted to cortical cytoplasmic following inhibitor treatment, similar to non-malignant mouse breast epithelial cells (EPH4). We are currently extrapolating these findings to a 3D Matrigel culture model in which EPH4 cells form acini-like spheroids with hollow lumen surrounded by a well-polarized outer layer of cells. Under these conditions, Stat3 levels are decreased followed by a reduction in cyclin D1 expression, while Src activation remains at a low baseline level. Interestingly,expression of Stat5, which has a reciprocal relationship with Stat3 in breast development and involution, is increased concomitant with elevated β-casein expression. Moreover, Fibronectin and HGF in combination stimulate tubular outgrowths with lumen filling. These findings suggest that aberrant changes in extracellular matrix milieu may stimulate integrin cross talk resulting in a switch of HGF/Met signaling to a transformation phenotype. Information from this study may lead to novel cancer therapies through targeting the HGF/Met and integrin signaling cascades. / Thesis (Master, Pathology & Molecular Medicine) -- Queen's University, 2008-09-19 18:19:22.744

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