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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.
101

The relationship between exercise, amenorrhoea, percentage body fat and disordered eating among adolescent female runners / T. Botha

Botha, Tershia January 2008 (has links)
Thesis (M.A. (Human Movement Sciences))--North-West University, Potchefstroom Campus, 2008.
102

The relations between parent training, family messages, cognitive triad, and girls’ depressive symptoms

Funk, Catherine Lee 10 October 2012 (has links)
It is important to understand the development of depression, and how a family component to treatment affects early adolescent girls’ depression given the association between depression and negative future outcomes. A potential vulnerability to depression is the cognitive triad, which encompasses beliefs about the self, world, and future and is shaped by early learning experiences. Research indicates that the vulnerability originates from parent-child relationships and family messages, which are important in the development of youth cognitive styles. Previous research also indicates that family variables are important factors to consider in the treatment of depression. The purpose of the current study was to expand previous research by examining the roles of perceived family messages and the cognitive triad in the development of depression for early adolescent girls. The study also explored whether parent gender differentiated how family messages affect girls’ cognitions and depressive symptoms. The study evaluated how the addition of a parent training component to a school-based, group-administered CBT intervention affected change in the model’s variables in comparison to group-administered CBT intervention alone and a monitoring control condition. Participants included early adolescent girls diagnosed with depression and caregivers in the parental treatment component. Girls were randomly assigned to a CBT, CBT+PT, or minimal contact control condition. Ratings of girls’ perceptions of family messages, cognitions, and depressive symptoms were obtained at pre-treatment and post-treatment. Results from structural equation modeling indicated significant effects from perceived family messages to girls’ cognitions. Further, girls’ cognitions mediated the relation between perceived family messages and girls’ depressive symptoms at post-treatment for participants within the CBT and monitoring conditions. No significant differences were evident between parent gender and perceived messages. Results indicated that the addition of a parent component to the CBT intervention did not significantly differ from the CBT intervention alone in its effects on the variable relations within the model at post-treatment. Supplemental analyses highlighted parent attendance as a significant factor, with larger effects from the family messages on girls’ cognitions appearing when parents attended majority (six or more) of the eight parent training sessions. Implications, limitations, and areas for further research are discussed. / text
103

The relationship between exercise, amenorrhoea, percentage body fat and disordered eating among adolescent female runners / T. Botha

Botha, Tershia January 2008 (has links)
Thesis (M.A. (Human Movement Sciences))--North-West University, Potchefstroom Campus, 2008.
104

The relationship between exercise, amenorrhoea, percentage body fat and disordered eating among adolescent female runners / T. Botha

Botha, Tershia January 2008 (has links)
Thesis (M.A. (Human Movement Sciences))--North-West University, Potchefstroom Campus, 2008.
105

Triarylborane-BODIPY Conjugates : White Light Emission, Multi-color Cell Imaging and Small Molecule Based Solar Cells

Sarkar, Samir Kumar January 2017 (has links) (PDF)
Luminescent boron containing materials find numerous applications in modern technologies such as display/lighting, bio-imaging and sensing. Thus, investigations of structure-property relationships in organic luminescent compounds to understand their molecular and bulk properties are of fundamental importance. The main thrust of this thesis is the development of facile synthetic routes for boron containing novel polyads and study their structure-property correlations and to utilize this information to design functional materials with desired properties such as multiple emission, bio imaging, anion sensing and organic photo voltaic characteristics. This thesis contains seven chapters and the contents of each chapter are described below. Chapter 1 This chapter is a concise overview of the recent developments in the chemistry of boron based molecular systems such as triarylborane and BODIPYs. This chapter also highlights the basic nature of broad emissive materials. In addition, an advance in the frontier areas such as bio imaging is discussed in brief. Chapter 2 This chapter describes the structure and optical properties of a new triad (Borane-Bithiophene-BODIPY) 1. Triad 1 exhibits unprecedented tricolour emission when excited at borane centred high energy absorption band and also acts as a selective fluorescent and colorimetric sensor for fluoride ion with ratiometric response. The experimental results are supported by computational studies. Chapter 3 Two fluorescent compounds with similar absorption profiles and complementarily emissive properties can be regarded as the ideal couple for the generation of white-light. Two structurally close and complementarily fluorescent boron based molecular siblings 2 and 3 were prepared. The luminescence properties of individual triads were modulated to an extent to complement each other by controlling the intramolecular energy transfer in triads by fine-tuning the dihedral angle between fluorophores in 2 and 3. A binary mixture of 2 and 3 emitted white-light. Chapter 4 This chapter deals with a straight forward strategy for the generation of white-light emission in aqueous media. Using a blue-emissive AIE-active (aggregation-induced emission) 1, 8-naphthalimide- based sensitizer and a boron-dipyrromethene based red emitter as a dopant, water dispersible nanostructures with tunable emission features are produced. The white-light emissive (WL) nano-aggregates are stable at neutral pH and have been elegantly utilized for four-colour cell imaging (including near- infrared imaging). Chapter 5 This chapter describes the design and development of a NIR emitting triarylborane decorated styryl-BODIPY (4) via a facile synthetic route. Incorporation of TAB entities results in a significantly red shifted broad emission in 4 (compared to compound M3 which is devoid of TAB unit). The near coplanar orientation of Ar3B planes and BODIPY core results in a highly efficient (TAB to BODIPY) EET process in 4. Conjugate 4 acts as a highly selective and sensitive fluoride sensor with naked eye visual response as well as ratiometric fluorescent response. The dual emission in fluoride bound 4 possibly results from the restricted partial TAB to BODIPY energy transfer. Chapter 6 This chapter describes how the energy of transitions of the broad emissive molecular triads can be fine-tuned by judiciously changing the spacer oligothiophene length. A series of triarylborane and BODIPY conjugates (TAB-π-BODIPY) has been designed, and synthesized by a combined strategy of changing the connection mode between the two units, extending the conjugation size by introducing terthiophene, quaterthiophene, and pentathiophene units. The electrochemical and photophysical behavior of these conjugates were investigated. The experimental findings were rationalized by density functional theory calculations. Chapter 7 This chapter describes design and development of boron based novel electron acceptor BDY for the bulk-heterojunction solar cell. The electron mobility values of BDY was found to be of the order of standard PCBM. Bulk-heterojunction was fabricated using BDY as the electron acceptor layer. The power conversion efficiency of the newly developed solar cells with BDY as electron acceptor is much higher than the value obtained for standard cells with PCBM as the electron acceptor.
106

Perfil redox da classificação clínica de polipose nasal / Profile redox of the clinical classification of nasal polyps

Canata, Diego Mena January 2016 (has links)
Introdução: A polipose nasal (PN) é considerada uma condição inflamatória crônica da mucosa da cavidade nasal e seios paranasais de etiologia não muito clara. Há poucos dados sobre alterações epiteliais em PN e sua relação com a ação dos radicais livres. Muitas doenças estão ligadas a danos causados por espécies reativas de oxigênio (ROS) e de nitrogênio (RNSS) e ocorrem de um desequilíbrio entre eles e antioxidantes, o que for maior atividade de espécies reativas, o que chamamos de estresse oxidativo. Objetivo: O objetivo principal deste estudo é avaliar o estresse oxidativo em pólipos removidos cirurgicamente em 3 grupos de pacientes com polipose nasal (com PN unicamente, PN associado à asma e PN associado à asma e intolerância ao ácido acetilsalicílico) a fim de elucidar possíveis diferenças no perfil redox nestes grupos. Material e Métodos: Cinquenta e nove pacientes com diagnóstico de polipose nasal foram divididos em três grupos clínicos: um grupo controle PN unicamente, um grupo asma (PN associado à asma) e um grupo Widal (PN associado à asma e intolerância ao ácido acetilsalicílico). Medição e Resultados Principais: Neste trabalho defesas enzimáticas (superóxido dismutase, consumo de peróxido de hidrogênio, glutationa peroxidase e glutationa S-transferase) e defesas não enzimáticas (glutationa total, nitritos e nitratos, vitamina C e E) foram analisados. Também foi realizada a medição de danos em lipídios (malondialdeído) e proteínas (carbonila). No grupo asma, o consumo de peróxido de hidrogênio, atividade da glutationa peroxidase, níveis de malondialdeído e vitamina E foram significativamente menores do que no grupo de controle. Também foi realizada a medição de danos em lipídios (malondialdeído) e proteínas (carbonila). No grupo Widal foram encontrados níveis significativamente maiores de glutationa e nitritos e nitratos em relação ao grupo controle. Não foram encontradas diferenças entre os grupos em relação ao nível de carbonila e glutationa, tamanho dos pólipos, atividades da superóxido dismutase e S-transferase. Conclusões: A classificação redox dos grupos de PN foi parcialmente alcançada. Os pólipos do grupo asma possuem alterações nas defesas enzimáticas relacionadas com o peróxido de hidrogênio e a peroxidação lipídica, enquanto pólipos do grupo Widal apresentaram alterações nos níveis de óxido nítrico e glutationa. / Introduction: Nasal polyposis (NP) is considered a chronic inflammatory condition of the mucosa of the nasal cavity and paranasal sinuses of etiology is not very clear. There are few data on epithelial changes in nasal polyposis and its relation to the action of free radicals. Many diseases are linked to damage caused by reactive oxygen species (ROS) and nitrogen (RNSs) and occur from an imbalance between them and antioxidants, whichever is greater activity of reactive species, what we call oxidative stress. Objective: The primary objective of this study is to evaluate oxidative stress in polyps surgically removed in 3 groups of patients with nasal polyposis, in order to elucidate possible differences in redox profile in these groups. Methods: Fifty nine patients diagnosed with nasal polyposis were divided into three groups: a control group, an asthma group (NP with asthma) and a Widal group (NP with asthma and aspirin intolerance) in which patients had an association of NP, asthma and aspirin intolerance. Measurement and main results: In this work enzymatic defenses (superoxide dismutase, hydrogen peroxide consumption, glutathione peroxidase and glutathione S-transferase) and non-enzymatic defenses (total glutathione, measurement of nitrites and nitrates, vitamin C and E) were analyzed. Also the measurement of damage in lipids (malondialdehyde) and proteins (carbonyl) was conducted. In the asthma group, hydrogen peroxide consumption, glutathione peroxidase activity, malondialdehyde, and vitamin E levels were significantly lower than in the control group. The Widal group showed significant higher glutathione levels, nitrite and nitrate levels than found in the control group. No differences were found among the groups regarding carbonyl level, polyp size, superoxide dismutase, and glutathione S-transferase activities. Conclusions: The redox classification of the groups of NP was partly achieved. Polyps of patients with asthma have changes in enzymatic defense pathways related to hydrogen peroxide and lipid peroxidation while polyps of patients with Widal triad present changes in nitric oxide and glutathione.
107

Perfil redox da classificação clínica de polipose nasal / Profile redox of the clinical classification of nasal polyps

Canata, Diego Mena January 2016 (has links)
Introdução: A polipose nasal (PN) é considerada uma condição inflamatória crônica da mucosa da cavidade nasal e seios paranasais de etiologia não muito clara. Há poucos dados sobre alterações epiteliais em PN e sua relação com a ação dos radicais livres. Muitas doenças estão ligadas a danos causados por espécies reativas de oxigênio (ROS) e de nitrogênio (RNSS) e ocorrem de um desequilíbrio entre eles e antioxidantes, o que for maior atividade de espécies reativas, o que chamamos de estresse oxidativo. Objetivo: O objetivo principal deste estudo é avaliar o estresse oxidativo em pólipos removidos cirurgicamente em 3 grupos de pacientes com polipose nasal (com PN unicamente, PN associado à asma e PN associado à asma e intolerância ao ácido acetilsalicílico) a fim de elucidar possíveis diferenças no perfil redox nestes grupos. Material e Métodos: Cinquenta e nove pacientes com diagnóstico de polipose nasal foram divididos em três grupos clínicos: um grupo controle PN unicamente, um grupo asma (PN associado à asma) e um grupo Widal (PN associado à asma e intolerância ao ácido acetilsalicílico). Medição e Resultados Principais: Neste trabalho defesas enzimáticas (superóxido dismutase, consumo de peróxido de hidrogênio, glutationa peroxidase e glutationa S-transferase) e defesas não enzimáticas (glutationa total, nitritos e nitratos, vitamina C e E) foram analisados. Também foi realizada a medição de danos em lipídios (malondialdeído) e proteínas (carbonila). No grupo asma, o consumo de peróxido de hidrogênio, atividade da glutationa peroxidase, níveis de malondialdeído e vitamina E foram significativamente menores do que no grupo de controle. Também foi realizada a medição de danos em lipídios (malondialdeído) e proteínas (carbonila). No grupo Widal foram encontrados níveis significativamente maiores de glutationa e nitritos e nitratos em relação ao grupo controle. Não foram encontradas diferenças entre os grupos em relação ao nível de carbonila e glutationa, tamanho dos pólipos, atividades da superóxido dismutase e S-transferase. Conclusões: A classificação redox dos grupos de PN foi parcialmente alcançada. Os pólipos do grupo asma possuem alterações nas defesas enzimáticas relacionadas com o peróxido de hidrogênio e a peroxidação lipídica, enquanto pólipos do grupo Widal apresentaram alterações nos níveis de óxido nítrico e glutationa. / Introduction: Nasal polyposis (NP) is considered a chronic inflammatory condition of the mucosa of the nasal cavity and paranasal sinuses of etiology is not very clear. There are few data on epithelial changes in nasal polyposis and its relation to the action of free radicals. Many diseases are linked to damage caused by reactive oxygen species (ROS) and nitrogen (RNSs) and occur from an imbalance between them and antioxidants, whichever is greater activity of reactive species, what we call oxidative stress. Objective: The primary objective of this study is to evaluate oxidative stress in polyps surgically removed in 3 groups of patients with nasal polyposis, in order to elucidate possible differences in redox profile in these groups. Methods: Fifty nine patients diagnosed with nasal polyposis were divided into three groups: a control group, an asthma group (NP with asthma) and a Widal group (NP with asthma and aspirin intolerance) in which patients had an association of NP, asthma and aspirin intolerance. Measurement and main results: In this work enzymatic defenses (superoxide dismutase, hydrogen peroxide consumption, glutathione peroxidase and glutathione S-transferase) and non-enzymatic defenses (total glutathione, measurement of nitrites and nitrates, vitamin C and E) were analyzed. Also the measurement of damage in lipids (malondialdehyde) and proteins (carbonyl) was conducted. In the asthma group, hydrogen peroxide consumption, glutathione peroxidase activity, malondialdehyde, and vitamin E levels were significantly lower than in the control group. The Widal group showed significant higher glutathione levels, nitrite and nitrate levels than found in the control group. No differences were found among the groups regarding carbonyl level, polyp size, superoxide dismutase, and glutathione S-transferase activities. Conclusions: The redox classification of the groups of NP was partly achieved. Polyps of patients with asthma have changes in enzymatic defense pathways related to hydrogen peroxide and lipid peroxidation while polyps of patients with Widal triad present changes in nitric oxide and glutathione.
108

Drift-Diffusion Simulation of the Ephaptic Effect in the Triad Synapse of the Retina

January 2013 (has links)
abstract: A general continuum model for simulating the flow of ions in the salt baths that surround and fill excitable neurons is developed and presented. The ion densities and electric potential are computed using the drift-diffusion equations. In addition, a detailed model is given for handling the electrical dynamics on interior membrane boundaries, including a model for ion channels in the membranes that facilitate the transfer of ions in and out of cells. The model is applied to the triad synapse found in the outer plexiform layer of the retina in most species. Experimental evidence suggests the existence of a negative feedback pathway between horizontal cells and cone photoreceptors that modulates the flow of calcium ions into the synaptic terminals of cones. However, the underlying mechanism for this feedback is controversial and there are currently three competing hypotheses: the ephaptic hypothesis, the pH hypothesis and the GABA hypothesis. The goal of this work is to test some features of the ephaptic hypothesis using detailed simulations that employ rigorous numerical methods. The model is first applied in a simple rectangular geometry to demonstrate the effects of feedback for different extracellular gap widths. The model is then applied to a more complex and realistic geometry to demonstrate the existence of strictly electrical feedback, as predicted by the ephaptic hypothesis. Lastly, the effects of electrical feedback in regards to the behavior of the bipolar cell membrane potential is explored. Figures for the ion densities and electric potential are presented to verify key features of the model. The computed steady state IV curves for several cases are presented, which can be compared to experimental data. The results provide convincing evidence in favor of the ephaptic hypothesis since the existence of feedback that is strictly electrical in nature is shown, without any dependence on pH effects or chemical transmitters. / Dissertation/Thesis / Ph.D. Applied Mathematics 2013
109

Estudo geoquímico, ecotoxicológico e ecológico do sedimento nas proximidades de um poço de perfuração na Bacia de Campos, Rio de Janeiro, Brasil

Moraes, Mariana Almeida de 08 February 2018 (has links)
Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2018-02-08T12:47:45Z No. of bitstreams: 1 TeseMarianaAlmeidadeMoraes2010.pdf: 2380840 bytes, checksum: bd5c94e7ec6b65c2e3b72d160c2ae7d9 (MD5) / Made available in DSpace on 2018-02-08T12:47:45Z (GMT). No. of bitstreams: 1 TeseMarianaAlmeidadeMoraes2010.pdf: 2380840 bytes, checksum: bd5c94e7ec6b65c2e3b72d160c2ae7d9 (MD5) / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / Os resíduos gerados da atividade de perfuração (fluidos e cascalhos) devem ser conhecidos e monitorados para que se compreenda a questão ambiental de poços marítimos das atividades de produção e exploração de óleo e gás. A avaliação da qualidade dos sedimentos é essencial para a compreensão dos processos que controlam a disponibilidade e a destinação dos contaminantes dispostos no ambiente marinho, uma vez que é o compartimento preferencial de armazenamento e transformação da maioria dos poluentes lançados pelo homem. O sedimento superficial do entorno do poço BJ-B caracterizou-se por apresentar predominância de sedimentos finos, principalmente silte, em todas as estações amostradas. Dos onze metais analisados, dois (mercúrio e cádmio) não foram detectados no sedimento de nenhuma das estações, nas duas campanhas realizadas no poço BJB. Os teores da maior parte dos metais encontrados no sedimento durante este monitoramento podem ser considerados normais para a região estudada. Apenas o teor de níquel mostrou valores mais elevados que o TEL estabelecido pela NOAA em todas as estações e o zinco após a perfuração. Todas as análises realizadas com os hidrocarbonetos mostraram que efetivamente a área onde foi realizada a perfuração do poço BJ-B, já se encontrava alterada, principalmente em um raio de 500m do poço, antes mesmo de iniciada a perfuração do poço BJ-B. A matriz de decisão da tríade da qualidade do sedimento gerada para este estudo, apresentou uma visão geral para cada ponto amostral. Observou-se também com a avaliação e comparação de nove estudos de monitoramentos nas proximidades de poços de perfuração a discrepância de formas de avaliação e número de parâmetros analisados exigidos pelo IBAMA no licenciamento. A tríade da qualidade do sedimento é proposta como uma ferramenta para estudos de monitoramento, podendo ser utilizada até mesmo pelo órgão ambiental, apresentando através das suas linhas de evidencia um retrato de cada estação amostral e como ela se comportou com a atividade de perfuração. / The waste generated from drilling activity (fluids and cuttings) must be known and monitored in order to understand the environmental issue of offshore activities like production and exploitation of oil and gas. Assessing the quality of sediments is essential for understanding the processes that control the availability and disposal of contaminants in the marine environment, since it is the preferred compartment for storage and processing of most pollutants released by humans. The sediment surface surrounding the BJ-B was characterized by a predominance of fine sediments, mainly silt, in all stations sampled. Of the eleven metals analyzed, two (mercury and cadmium) were not detected in the sediment of all stations in the two campaigns in the BJ-B. The levels of most metals found in the sediment during this monitoring can be considered normal for the region studied. Only the nickel content showed higher values than the TEL established by NOAA in all seasons and zinc after drilling. All tests carried out showed that the hydrocarbons effectively the area where it was performed the drilling of the BJ-B, was already changed, especially in a 500m radius of the well, even before we started the drilling of the BJ-B. The decision matrix of the Sediment Quality Triad generated for this study presented an overview for each sample point. It was also observed with the evaluation and comparison of nine studies in the Campos Basin, that shows discrepancy in the way of evaluated and the number of parameters analyzed required by IBAMA in a licensing process. The Sediment Quality Triad is proposed as a tool for monitoring studies and may be used even by the environmental agency, showing through their lines a picture of each sampling station and how it behaved with the drilling activity
110

[en] AUTISM: A SENSORY NATURE DISORDER? / [pt] AUTISMO: UM TRANSTORNO DE NATUREZA SENSORIAL?

ROBERTA COSTA CAMINHA 30 March 2009 (has links)
[pt] O diagnóstico do autismo é feito com base na tríade de prejuízos que engloba problemas na comunicação, nos comportamentos sociais e padrões restritos e repetitivos de comportamentos, interesses e atividades. Embora esse critério diagnóstico não faça referência em momento algum a prejuízos sensoriais, crescem as evidências, advindas principalmente de relatos autobiográficos de autistas de alto funcionamento, de que o transtorno autista seja uma condição diretamente relacionada a um aparato sensorial imperfeito. Essas evidências são complementadas com pesquisas científicas que levam em consideração, em sua maioria, relatos retrospectivos de pais e cuidadores. Estudos indicam que problemas sensoriais já estão aparentes no primeiro ano de vida de uma criança autista, podendo inclusive ser úteis para um rastreamento precoce do transtorno. Considerando-se a importância do aparato sensorial para o desenvolvimento das relações interpessoais do bebê e o fato de 69% a 80% dos autistas apresentarem problemas sensoriais, o objetivo do trabalho é iniciar uma reflexão sobre a possível relação da tríade de prejuízos do autismo com um aparato sensorial imperfeito no bebê, começando a se pensar no autismo como, talvez, um transtorno de natureza sensorial. / [en] The diagnosis of autism is based on a triad of impairments that includes communication problems, social impairments and repetitive and restricted patterns of behaviors, interests and activities. Although this diagnosis criterion does not make reference to sensory impairments, evidence arising from autobiographical accounts of high-functioning individuals with autism, suggests that the autistic disorder is directly related to an impaired sensory apparatus. Such evidence is complemented with scientific research based mostly on retrospective accounts from parents and caretakers. Studies indicate that by the first year of an autistic child´s life, sensory impairments are already apparent, and may be useful to an early identification of the disorder. Considering the importance of the sensory apparatus to the development of a child´s interpersonal relations and the fact that approximately 69% to 80% of autistic individuals present sensory problems, the purpose of this work is to suggest a link between the triad of impairments associated with autism and an impaired sensory apparatus in babies, thus starting to approach autism as, perhaps, a disorder of sensory nature.

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