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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.
111

A criança com autismo: trajetórias desenvolvimentais atípicas à luz da teoria piagetiana da equilibração / The child with autism: atypical developmental trajectories in light of Piagets equilibration theory

Camilla Teresa Martini Mazetto 27 October 2015 (has links)
Os Transtornos do Espectro do Autismo (TEA) refletem alterações neurológicas das funções psicológicas que se desenvolvem durante os primeiros anos de vida. Estudos atuais apontam uma prevalência crescente, relacionada com as mudanças dos critérios diagnósticos. As alterações nosológicas evidenciam a variabilidade de expressões clínicas, que compõem um continuum de quadros diversos, com evoluções particulares. A pesquisa toma a perspectiva da psicopatologia desenvolvimental, e estuda os mecanismos gerais de desenvolvimento psicológico aplicados a um contexto atípico de desenvolvimento. O desenvolvimento cognitivo e socioemocional típico tende a uma construção hierárquica, relativamente homogênea, guiada por uma equilibração progressiva. No autismo parece haver uma heterogeneidade no desenvolvimento das funções cognitivas e sociais. Observam-se atrasos mais ou menos significativos, estagnação ou regressão em determinadas funções, evocando uma perturbação fundamental da regulação da atividade sensório-motora. Uma das hipóteses desse desenvolvimento particular, é a de um distúrbio da regulação do conjunto das atividades da criança. O objetivo geral é apresentar uma leitura conceitual, apoiando-se na teoria piagetiana da equilibração, sobre trajetórias de desenvolvimento de crianças com autismo, a partir de indicadores clínicos fornecidos pela Bateria de Avaliação Cognitiva e Socioemocional (BECS). A pesquisa conta com duas partes de coleta de dados, e uma parte teórica. Na primeira, apresenta o estudo comparativo do desenvolvimento cognitivo e socioemocional de um grupo de crianças com autismo (N= 20) e um grupo de crianças típicas (N= 20). Na segunda, descreve a trajetória de quatro casos ilustrativos de crianças com autismo acompanhadas ao longo de 18 meses, com avaliações sucessivas a cada seis meses. Os resultados indicam que crianças com autismo mesmo mais velhas apresentam um funcionamento psicológico próprio às primeiras etapas de estruturação cognitiva, centrada nas aquisições sensório-motoras. Quanto à hipótese da heterogeneidade desenvolvimental característica do autismo, foram notadas similitudes entre os processos típicos e atípicos, sendo que a heterogeneidade é uma característica das etapas mais inicias de desenvolvimento, em ambos os contextos. Por outro lado, crianças com autismo apresentaram níveis de socialização e de atenção conjunta bastante abaixo daqueles apresentados pelo grupo de crianças típicas, com sinais de maior habilidade para o desenvolvimento cognitivo. A leitura conceitual dos casos sugere a preservação dos mecanismos gerais da equilibração majorante, com ampliação gradual do desenvolvimento global. A heterogeneidade pode assim traduzir um processo positivo de desenvolvimento, apoiando-se nos desequilíbrios como fonte para regulações e reequilibrações, tanto no contexto típico quanto atípico. Entretanto, no caso de crianças com autismo, as trajetórias apresentam características particulares, com maior estabilidade para a ampliação das construções cognitivas, e fragilidade inicial para a consolidação das habilidades socioemocionais / The Autism Spectrum Disorders (ASD) reflect neurological impairments of psychological functions that develop during the first years of life. Recent studies point to an increasing prevalence, related to changes in diagnostic criteria. The nosological changes demonstrate the variability of clinical expressions, which make up a continuum of different frames, with particular evolutions. This research takes the perspective of developmental psychopathology and studies the general mechanisms of psychological development applied to an unusual context of development. The typical cognitive and social-emotional development tends to a hierarchical construction, relatively homogeneous, guided by a progressive equilibration. In autism there appears to be heterogeneity in the development of cognitive and social functions. Significant or milder delays, stagnation or regression in certain functions are observed, evoking a fundamental disturbance in the regulation of sensory-motor activity. One hypothesis of this particular development is a disorder of the child\'s activities regulation. The overall goal is to present a conceptual study, based on Piaget\'s equilibration theory and on clinical indicators provided by the he Social Cognitive Evaluation Battery for Children with Autism (SCEB), regarding developmental trajectories of children with ASD. The research has two parts of data collection, and a theoretical part. The first part presents a comparative study of cognitive and socio-emotional development of a group of children with autism (N = 20) and a group of typical children (N = 20). The second part describes the trajectory of four illustrative cases of children with autism accompanied over 18 months, with successive evaluations every six months. The results indicate that even older children with autism show a psychological functioning that corresponds to earlier stages of cognitive structuring, focused on sensorimotor acquisitions. As for the hypothesis of characteristic developmental heterogeneity in autism, similarities between typical and atypical contexts of development were noted, and that heterogeneity is a feature of the initial stages of development, in both contexts. On the other hand, children with autism showed socialization levels and joint attention well below those presented by the group of typical children, with signs of greater ability for cognitive development. The conceptual reading of the cases suggests the preservation of the general mechanisms of equilibration, with gradual expansion of global development. The heterogeneity can thus translate a positive development process, drawing on the imbalances as a source for adjustments and rebalance, in both typical and atypical contexts. However, for children with autism, the trajectories have particular characteristics, with greater stability for the expansion of cognitive structures, and initial weakness to the consolidation of socio-emotional skills
112

Análise de patentes no setor de equipamentos para radioterapia: um estudo sobre as rotas tecnológicas neste segmento / Patent analysis in radiation therapy devices field: a technological trajectories study in this segment.

Flávio Augusto José 20 August 2014 (has links)
A propriedade intelectual tem se tornado cada vez mais importante e é uma parte fundamental do desenvolvimento. No entanto, ainda é pouca literatura sobre a avaliação desses ativos intangíveis. Não se sabe ao certo sequer quais variáveis (idade, número de citações, atividade inventiva etc.), estabelecem o valor de uma patente, e essas variáveis podem diferir dependendo do setor. Também pouco se sabe sobre como se relacionam umas com as outras em termos de formação rotas tecnológicas, e quais fatores mais importantes para uma patente ser usada como inspiração para outra invenção. Neste trabalho são usadas análises de redes formadas pelas citações das patentes do segmento de equipamentos para radioterapia para descobrir o que os principais atores produziram nos últimos vinte anos no mercado de equipamentos para radioterapia. Foram levantados também os países de maior interesse de proteção dessas invenções, os principais atores no mercado. Tendências tecnológicas foram analisadas pelas formações de clusteres de reivindicações de tais documentos. Descobriu-se que a formação da rede e dos grupos de patentes têm como principal característica a semelhança das tecnologias envolvidas e, também, de fatores geográficos. Os principais playeres são grandes companhias de países desenvolvidos e praticamente não há proteção de invenções deste segmento em países emergentes ou subdesenvolvidos, com exceção da China. / Intellectual property has become increasingly important and is a key part of the development. However, it is still little literature on the valuation of these intangible assets. No one knows for sure even what variables (age, number of citations, inventive activity etc.), set the value of a patent, and these variables may differ depending on the sector. Also little is known about how they relate to each other in terms of technological routes formation, and which are the most important factors for a patent to be used as inspiration for other invention. This work analyzes the networks formed by the citations of the patents in the radiation therapy devices segment to find out what the main actors produced in the last twenty years in the radiotherapy equipment market. Countries of greatest interest to protect these inventions and the principal players were also pointed. Technological trends were identified by the formation of clusters of documents\' claims. It was found that the formation of the network and groups of patents have as main feature the likeness of the technologies involved, and also geographic factors. The main players are large companies from developed countries and there is virtually no protection for inventions in this segment in emerging or developing countries, excluding China.
113

Contribuições de trajetórias complexas ao propagador semiclássico para estados coerentes / Contributions of complex trajectories to semiclassical propagator for coherent states

Barreto, Wendell Pereira, 1987- 01 July 2014 (has links)
Orientador: Marcus Aloizio Martinez de Aguiar / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-24T22:36:15Z (GMT). No. of bitstreams: 1 Barreto_WendellPereira_M.pdf: 1811207 bytes, checksum: 0f8c73a79029cd1792710999b0f258a0 (MD5) Previous issue date: 2014 / Resumo: A evolução temporal de estados quânticos é estudada do ponto de vista semiclássico usando o propagador na representação de estados coerentes. No limite semiclássico o propagador pode ser calculado em termos de soluções complexas das equações de Hamilton que devem satisfazer condições de contorno apropriadas. No entanto, nem todas as soluções podem ser utilizadas no cálculo do propagador. Certas trajetórias, denominadas não contribuintes devem ser descartadas, pois dão contribuições incorretas ao propagador. Aqui, exploramos a questão das trajetórias não contribuintes, que é um dos problemas mais sérios na aplicação sistemática das expressões semiclássicas envolvendo órbitas complexas. Para isso consideramos uma classe de problemas unidimensionais não-lineares onde as soluções clássicas e quânticas poder ser obtidas analiticamente. Dessa forma, o propagador semiclássico pode ser escrito de forma explícita, o que permite uma análise detalhada da contribuição de cada trajetória. Definimos então um critério mais preciso para a exclusão de soluções espúrias e, enfim, melhorar o cálculo semiclássico. O sistema foco neste estudo foi o oscilador harmônico ao quadrado, cuja dinâmica tem solução analítica e está presente em problemas de óptica não linear / Abstract: The time evolution of quantum states is studied in the semiclassical limit using the semiclassical propagator in the coherent-state representation. In the semiclassical limit the quantum propagator can be calculated with complex solutions of Hamilton's equations satisfying appropriate boundary conditions. However, not all these solutions can be used in the expression for the propagator. Some trajectories, called non contributing trajectories, give incorrect contributions to the propagator and should be excluded. In this work the issue of non-contributing trajectories, which is one of the most serious problems in the systematic application of semiclassical expression involving complex orbits, is studied. We explore a class of nonlinear one-dimensional problems for which classical and quantum solutions can be analytically obtained. For these problems, the semiclassical propagator can be written explicitty allowing a detailed analisys of the contribution of each trajectory. In this work we will focus on the ''squared harmonic oscillator'', it can be solved analytically and it is present in problems of nonlinear optics / Mestrado / Física / Mestre em Física
114

Chronic Runaway Youth: A Gender-Based Analysis

Jeanis, Michelle N. 04 July 2017 (has links)
Runaway youth often face a multitude of negative experiences during their childhood, which often leads to trajectories of psychological disorder/distress, victimization, and offending. This propensity for negative life trajectories may be exacerbated by repetitive runaway behavior. Additionally, these negatives experiences may be further shaped by the gender of the youth, thus creating distinct gendered pathways to chronic runaway behavior, victimization, and offending. This study utilized a sample of youth runaways in the state of Florida (N=295) to build upon the classification/typology research on juvenile runaways by assessing the presence of latent groups of youth based on runaway frequency. In addition, this study utilized classical and modern criminology theories to influence the assessment of the relationship between known runaway risk factors and chronic runaway status. Group-based trajectory modeling was performed and two distinct groups of youth runaways were identified for both full and gender-exclusive models. Chronic runaway analyses indicated both unique and similar gender-based relationships between chronic runaway status and relevant risk factors, suggesting partial support for a gender specific theoretical perspective. Results provide additional insight into youth runaway behavior while also suggesting the need for further exploration of chronic runaway status within the youth runaway population.
115

Gravitational capture

Anderson, Keegan Doig 02 November 2012 (has links)
M.Sc. / Important ideas from dynamical systems theory and the restricted three-body problem are introduced. The intention is the application of dynamical systems theory techniques to the restricted three-body problem to better understand the phenomenon of gravitational capture. Chapter 1 gives a much deeper review of the purpose of this dissertation. Chapter 2 introduces and reviews important concepts from dynamical systems. Chapter 3 reviews the restricted three-body problem and all important aspects of the problem. In chapter 4 we define and study the phenomenon of gravitational capture. We take a novel approach by applying a symplectic method, namely the implicit midpoint method, to model trajectories in the restricted three-body problem. As far as we know, this is the first time such a method has actually been applied, with other authors preferring to apply explicit methods in trajectory modelling. In the closing of this chapter we review our whole discourse and suggest topics for future research. The disseration is concluded with two appendix chapters. In the first chapter we list all the computer code we have written for this dissertation. The second appendix chapter reviews the n-body problem and we show a full solution of the two-body problem.
116

West Florida Shelf Connectivity: An Exploratory Study

Reinert, Amanda Sue 21 March 2016 (has links)
This Thesis explores the connectiveness of the West Florida Shelf’s various areas of economic and ecological importance by considering five case studies of varying dynamic forcing influences and time. The advection of water about the shelf moves nutrients and has a direct impact on the shelf’s ecology and the determination of whether or not the shelf will be oligotrophic at any given time or location. The case studies are analyzed both quantitatively and qualitatively after quasi-isopycnal particle trajectory calculations are completed for each. The findings support a combination of local and deep-ocean forcing being ideal for the maximum advection and opportunity for potential connectivity between areas of the shelf, and provide a solid guide for moving forward with a considerable ensemble of studies in the future to approach the question from a statistical perspective. The numerical scheme used to calculate the particle trajectories is a 4th order Runge-Kutta method. The scheme is investigated for it appropriateness and pitfalls as a backward trajectory calculation tool by direct comparison between forward trajectory calculations and attempting to replicate the result in the backward direction. The findings support that the more linear the trajectory and the more restrictive the dynamics acting upon a particle at any given location, the better the backward and forward replication will be, although it is still an approximation, much like any other iterative tool used for approximating a solution to an ordinary differential equation.
117

Temperament, parenting, and the development of childhood obesity

Hejazi, Samar 05 1900 (has links)
The purpose of this study was two-fold: (a) to identify, in a large representative sample of Canadian children, the age-related trajectories of overweight and obesity from toddlerhood into childhood and (b) to investigate the associations between these trajectories and children’s temperaments, their parents’ parenting practices and their interactions. Potentially important familial characteristics (i.e., the parents’ or surrogates’ age, income level, and educational attainment) were considered in the models. The sample for this study was drawn from the Canadian National Longitudinal Survey of Children and Youth (NLSCY). Group-based mixture modeling analyses were conducted to identify the number and types of distinct trajectories in the development of obesity (i.e., to explicate the developmental processes in the variability of childhood obesity) in a representative sample of children who were between 24 to 35 months of age, at baseline, and followed biennially over a 6-year span. Discriminant analysis was conducted to assess the theoretical notion of goodness-of-fit between parenting practices and children’s temperament, and their association with membership in the BMI trajectory groups. The results of the group-based modeling established three different BMI trajectories for the boys, namely: stable-normal BMI, transient-high BMI, and j-curve obesity. The analyses revealed four different trajectories of BMI change for the girls: stable-normal BMI, early-declining BMI, late-declining BMI, and accelerating rise to obesity. The multivariate analysis revealed that the combined predictors of the obesity trajectories of the girls (group membership) included having a fussy temperament, ineffective parenting, and parents’ educational attainment. Predictors of the boys’ obesity trajectory (group membership) included household income, parental education, and effective parenting practices. Understanding the different ways in which a child may develop obesity will allow nurses and other health professionals to take different approaches in the assessment, intervention and evaluation of obesity and obesity-related health problems. The results of this study further our understanding of factors associated with the development of obesity at a young age and hence may inform the development of early preventive programs. / Applied Science, Faculty of / Nursing, School of / Graduate
118

Inferring lifestyle and locomotor habits of extinct sloths through scapula morphology and implications for convergent evolution in extant sloths

Grass, Andy Darrell 01 July 2014 (has links)
Despite the restricted morphology and distribution of sloths today, fossils sloths show a wide variety of forms and behaviors and used to range from South America to Alaska. These extinct forms have in the past simply been lumped together as "ground sloths", separated from modern "tree sloths". However there are intermediate forms that have been posited to be semi-arboreal. In other groups such as primates the shape of the shoulder blade has been shown to vary significantly between groups with different arboreal behaviors. This study used geometric morphometrics to examine the scapulae of modern and extinct sloths to show that these three locomotor groups can in fact be distinguished by their shoulder blade shape. Juveniles of giant ground sloths also have significantly different shoulder blade shapes than the much larger adults, however they do not overlap with the smaller intermediate sloths, so may have been just as terrestrial as their parents despite their much smaller size. Finally, ontogenetic trajectories of several sloth genera do not show evidence of having different slopes. They start and end in different areas of morhospace but are all on parallel paths. This argues against the hypothesis of convergence in modern tree sloths, which despite both having an unusual suspensory lifestyle are not closely related. Rather they are both retaining an ancestral growth trajectory that all sloths have possessed.
119

Key Factors Influencing Longevity in Ohio's School Superintendents

Bowser, Brian R. 15 July 2021 (has links)
No description available.
120

Genericity on Submanifolds and Equidistribution of Polynomial Trajectories on Homogeneous Spaces

Zhang, Han January 2021 (has links)
No description available.

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