The focus of this thesis falls on school violence. The research addresses the possibility that a culture of violence exists amongst some South African school-going youth. The researcher identified the attitudes and behaviour of learners towards violence as indicators of the culture of these learners. The research specifically focused on the pro-violence attitudes and violent behaviour of learners. The definition of ‘culture’ which was employed suggests the link between a person’s attitude, behaviour and culture. Information was gathered through literature and empirical research. The data was collected by means of a questionnaire with closed-ended questions and a well-tested tool, namely the Attitudes towards Violence Scale. The results of the empirical research were analyzed with the SPSS Windows data editor computer program. Conclusions and recommendations regarding school violence were made. In addition, a programme to curb such violence was proposed. Some suggestions for further research into this subject were also advanced. / Criminology and Security Science / M.A. (Criminology)

La sclérose latérale amyotrophique (SLA) est une pathologie complexe multifactorielle dont les mécanismes de dégénérescence des motoneurones et de propagation rapide au sein du système nerveux sont encore incertains. Par l’utilisation du nématode Caenorhabditis elegans, nous avons pu investiguer génétiquement et pharmacologiquement certains facteurs entrant en jeu dans la toxicité de TDP-43 et FUS. Des mutations dominantes dans ces protéines liant l’ADN et l’ARN, structurellement et fonctionnellement proches, sont des causes de SLA familiales. Nous avons, par le passé, construit un modèle de ver transgénique possédant le gène TARDBP ou FUS codant respectivement pour les protéines humaines TDP-43 ou FUS, sous le contrôle d’un promoteur exprimé seulement dans les neurones GABAergiques. Uniquement lorsque les gènes TARDBP ou FUS sont mutés, des symptômes relatifs à la SLA apparaissent au cours du temps, à savoir une paralysie progressive et une neurodégénérescence des motoneurones GABAergiques. Nous avons voulu connaître le rôle que pouvait jouer le système immunitaire, dont des évidences croissantes montrent une implication dans la SLA, dans la protéotoxicité liée à ces protéines dans nos modèles de ver. Dans un premier temps, nous avons évalué la motricité des vers en milieu solide et en milieu liquide, et grâce à des vers transgéniques exprimant la GFP dans les neurones GABAergiques, nous avons pu quantifier la neurodégénérescence. Nos résultats soulignent un rôle prévalent de l’orthologue de la protéine du système immunitaire innée Sarm1 chez le ver, TIR-1, ainsi que les kinases en aval dans la pathologie. Nous avons pu, de surcroît, utiliser le marqueur NLP-29 dont le promoteur lié à la GFP nous indique l’activation de la voie Sarm1 dans l’ensemble du ver et non seulement dans les neurones. De manière intéressante, l’activation de ces protéines se produit entre autres dans des cellules non-neuronales de manière paracrine suggérant qu’un signal de danger opère extracellulairement et vraisemblablement à travers un récepteur membranaire. Ces dernières années, un nombre important d’études met en lumière le rôle proéminent des microARNs dans des maladies telle que la SLA. Classiquement vus comme des régulateurs de l’expression post-transcriptionnelle, ce qui en font notamment des outils antiviraux puissants, ils peuvent agir à d’autres niveaux et notamment comme ligands de récepteurs Toll-like (TLRs), eux aussi impliqués dans la SLA. iv Outre le potentiel biomarqueur de ces petites molécules, nous avons investigué leur rôle dans la neurodégénérescence observée dans la SLA. Ainsi, dans une deuxième partie d’étude, nous avons utilisé des mutants pour différentes protéines impliquées dans la biogénèse des microARNs et trouvé qu’elles étaient partie intégrante du processus de paralysie et de dégénérescence des vers TDP-43A315T. Plus encore, le microARN let-7 pourrait être une molécule signal transitant entre les neurones et les cellules avoisinantes. Enfin, des analyses bio-statistiques prédisent la possibilité que let-7 se lie au récepteur TOL-1, l’unique orthologue des TLRs chez C. elegans. Les propriétés des microARNs en font en effet des cibles de choix dans la recherche de nouveaux acteurs dans la SLA et de potentielles cibles thérapeutiques. / Amyotrophic lateral sclerosis is a complex multifactorial pathology characterized by the progressive spread of motor neuron degeneration. Unfortunalety, the underlying disease mechanisms remain unclear. By using the nematode Caenorhabditis elegans, we were able to investigate genetically and pharmacologically some factors involved in TDP-43 or FUS proteotoxicity. Dominant mutations in these structurally and functionally similar DNA/RNA binding proteins, are causative for familial ALS. We have constructed transgenic C. elegans models expressing human TARDBP or FUS genes - encoding respectively TDP-43 and FUS - only in GABAergic motor neurons. In these transgenics animals, the expression of mutant TARDBP or FUS alleles results in early the motor deficits leading to age-dependent paralysis accompanied by neuronal protein aggregation. Using transgenic strain expressing GFP in GABAeric neurons, we found an increased rate of neurodegeneration in TDP-43 and FUS mutants. With these models we investigated the potential role of the innate immune system as a modifier of these phenotypes. Our results highlight a prevalent role for the worm’s innate immune system, and specifically the TIR-1/Sarm1 pathway and associated downstream kinases in neurodegeneration. We used GFP fluorescence linked to NLP-29 promoter to indicate Sarm1 pathway activation in the entire worm. Interestingly, activation of the TIR-1/Sarm1 pathway occurs in a paracrine manner in non-neuronal cells, suggesting that a danger signal operates extracellularly likely through a membrane receptor. In a past few years, a number of studies have highlighted the prominent role of microRNAs in diseases such as ALS. Traditionally seen as post-transcriptional regulators, what makes them powerful antiviral tools is that they can act at other levels and in particular as Toll-like receptors (TLRs) ligands, also involved in ALS. In addition to the biomarker potential of these small molecules, we investigated their role in the neurodegeneration observed in ALS. As a result, in the a second section of this study, we used worms mutant for several proteins involved in the biogenesis of microRNAs and found that they were involved in the process of TDP-43A315T-independent paralysis and neurodegeneration. Moreover, the microRNA let-7 seems to be a signal molecule involved in the non-cell autonomous trans-neuronal and trans-cellular spread of motor neuron degeneration. Finally, bio-statistical analyzes predict the possibility that let-7 binds to the vi TOL-1 receptor, the single ortholog of TLRs in C. elegans. Thus microRNAs may be prime targets for ALS therapeutic intervention.

Introdução: A deglutição e suas características principais ainda são desconhecidas na demência frontotemporal. Objetivos: Caracterizar a deglutição e o comportamento alimentar de pacientes com diagnóstico de demência frontotemporal que apresentam a variante comportamental (DFTvc) e a afasia progressiva primária (APP). Caracterizar os pacientes com DFT e seus cuidadores. Descrever aspectos cognitivos e comportamentais, funcionalidade global, comunicação funcional, e a funcionalidade da deglutição na DFT. Descrever os problemas de deglutição e do comportamento alimentar na DFTvc e APP. Correlacionar os aspectos cognitivos e comportamentais, funcionalidade global e a comunicação com as características da deglutição. Identificar fatores preditivos da piora da funcionalidade da deglutição e do comportamento alimentar na DFT. Avaliar o comportamento dos instrumentos empregados. Desenvolver a versão reduzida do Questionário de Habilidades de Alimentação e Deglutição nas Demências e do Questionário de Comunicação Funcional na Afasia. Método: Este estudo incluiu 46 indivíduos com DFT nas fases leve, moderada e grave, e seus 46 cuidadores. O Mini exame do estado mental (MEEM) e o Mini exame do estado mental grave (MEEM-g) foram usados para avaliar os aspectos cognitivos. A Escala de estadiamento da demência (CDR-DLFT) foi usada para confirmar a fase da doença. O Inventário Neuropsiquiátrico (INP) foi aplicado para investigar os problemas comportamentais. A Bateria de Avaliação Frontal (BAF) investigou as funções executivas. O Índice das Atividades de Vida Diária (Katz), Questionário para Avaliação da Comunicação Funcional na Afasia (QACFA) e a Escala de funcionalidade da deglutição (EFD) avaliaram as habilidades funcionais. O Questionário de Habilidades de Alimentação e Deglutição nas Demências (QHADD) avaliou as dificuldades na deglutição e alimentação. Resultados: Os grupos DFTvc e APP não mostraram diferença estatisticamente significante no MEEM, CDR e BAF. Os cuidadores dos pacientes com DFTvc apresentaram mais horas de cuidado por dia em comparação aos pacientes com APP (p<0,05). Os grupos diferiram na EFD (p < 0,05). As características comportamentais que foram significantes na comparação entre os grupos DFTvc e APP foram: delírio, desinibição, comportamento motor aberrante e distúrbios do sono(p < 0,05) e alucinação (p=0,01). Os pacientes com DFTvc tiveram mais problemas de deglutição do que os pacientes com APP, tais como: tosse e engasgos, dificuldade com alguma consistência alimentar e dificuldade com alimento específico. Os problemas de deglutição na DFTvc se correlacionaram com a funcionalidade, aspectos cognitivos (p < 0,05), com a função executiva e com o comportamento (p < 0,01). Na APP, o subtipo semântico apresentou mais problemas de deglutição, tais como: escape de saliva e comida da boca, múltiplas deglutições, atraso na iniciação da deglutição e engasgos, estas características se correlacionaram com a ansiedade (p < 0,01), apatia e comportamento motor aberrante (p=0,01). Os problemas do comportamento alimentar foram mais frequentes no subtipo logopênico e se correlacionaram com dificuldades de comunicação. Os principais fatores preditivos da piora da funcionalidade da deglutição foram: declínio funcional, alterações comportamentais e o comprometimento da comunicação. Os problemas de deglutição foram observados em todas as fases da demência. A BAF foi o único instrumento que não apresentou uma boa confiabilidade interna. Conclusão: Problemas na deglutição foram observados nas duas variantes desde os estágios iniciais da demência. As alterações comportamentais, cognitivas e funcionais, e dificuldades na comunicação comprometeram as fases antecipatória e preparatória oral da deglutição. Por causa destas alterações, os cuidadores tiveram dificuldade no gerenciamento da situação de alimentação. Nosso estudo desenvolveu questionários resumidos para avaliar a deglutição e a comunicação funcional / Introduction: Swallowing and its main characteristics are still unknown in frontotemporal dementia. Objectives: To characterize swallowing and feeding behavior of patients with frontotemporal dementia who have behavioral variant (bvFTD) and primary progressive aphasia (PPA). To characterize patients with FTD and their caregivers.To describe cognitive and behavioral aspects, functionalstatus, functional communication, and swallowing function in FTD.To describe swallowing problems and feeding behavior in bvFTD and PPA. To correlate cognitive and behavioral aspects, functional status, and communication with swallowing. To identify predictive factors associated with worsening of functionality of swallowing and feeding behavior in FTD. To evaluate the instruments used. To develop reduced versions of: \"Assessment of Feeding and Swallowing Difficulties in Dementia\" and \"Functional Outcome Questionnaire Aphasia\". Method: This study included 46 individuals with FTD in mild, moderate and severe phases, and their 46 caregivers. The Mini mental state examination (MMSE) and the Severe Mini mental state examination (SMMSE) were used to assess the cognitive aspects. The FTLD-modified Clinical Dementia Rating scale (FTLD-CDR) was used to confirm the stage of the disease. The Neuropsychiatric Inventory (NPI) was applied to investigate the behavioral problems. The Frontal Assessment Battery (FAB) investigated executive functions. The Index of Activities of Daily Living (Katz), Functional Outcome Questionnaire- Aphasia and Swallowing rating scale (SRE) evaluated the functional abilities. The Assessment of Feeding and Swallowing Difficulties in Dementia (QHADD) evaluated the difficulties in swallowing and feeding. Results: bvFTD and PPA groups showed no statistically significant difference in MMSE, CDR and FAB. Caregivers of patients with bvFTD had more hours of care per day compared to patients with PPA (p < 0.05). The groups differed in SRE (p < 0.05). The behavioral characteristics that were significant in the comparison between bvFTD and PPA groups were delirium, disinhibition, aberrant motor behavior and sleep disturbances (p < 0.05), and hallucinations (p = 0.01). Patients with bvFTD had more swallowing problems than patients with PPA, such as coughing and choking, difficulty with some food consistency and difficulty with specific food. Swallowing problems in bvFTD correlated with functionality, with the cognitive aspects (p < 0.05), with executive function and behavior (p < 0.01). In PPA, the semantic subtype showed more swallowing problems such as escape of saliva and food in mouth, multiple swallows, delay in initiation of swallowing and choking, these characteristics correlated with anxiety (p < 0.01), apathy and aberrant motor behavior (p = 0.01). The problems of feeding behavior were more frequent in logopenic subtype and correlated with communication difficulties. The major predictors of worsening of swallowing function were: functional decline, behavioral changes and impaired communication. Swallowing problems were observed at all stages of dementia. The BAF was the only instrument that had bad internal reliability. Conclusion: Swallowing problems were observed in the two variants from the early stages of dementia. Behavioral, cognitive and functional changes, and difficulties in communication compromised the anticipatory and oral preparatory phase of swallowing. Because of these changes, caregivers had difficulty in managing the feeding situation. Our study developed reduced versions of questionnaires to assess swallowing and functional communication

In der vorliegenden Arbeit untersuchen wir schwache Lösungen, die zu einem geeigneten Sobolevraum gehören, q-elliptischer und parabolischer Systeme partieller Differentialgleichungen auf deren Regularität für den Fall 1 / In the present work we study the regularity of weak solution to q-elliptic and parabolic systems partial differential equations in appropriate Sobolev spaces in case 1

Introdução: A deglutição e suas características principais ainda são desconhecidas na demência frontotemporal. Objetivos: Caracterizar a deglutição e o comportamento alimentar de pacientes com diagnóstico de demência frontotemporal que apresentam a variante comportamental (DFTvc) e a afasia progressiva primária (APP). Caracterizar os pacientes com DFT e seus cuidadores. Descrever aspectos cognitivos e comportamentais, funcionalidade global, comunicação funcional, e a funcionalidade da deglutição na DFT. Descrever os problemas de deglutição e do comportamento alimentar na DFTvc e APP. Correlacionar os aspectos cognitivos e comportamentais, funcionalidade global e a comunicação com as características da deglutição. Identificar fatores preditivos da piora da funcionalidade da deglutição e do comportamento alimentar na DFT. Avaliar o comportamento dos instrumentos empregados. Desenvolver a versão reduzida do Questionário de Habilidades de Alimentação e Deglutição nas Demências e do Questionário de Comunicação Funcional na Afasia. Método: Este estudo incluiu 46 indivíduos com DFT nas fases leve, moderada e grave, e seus 46 cuidadores. O Mini exame do estado mental (MEEM) e o Mini exame do estado mental grave (MEEM-g) foram usados para avaliar os aspectos cognitivos. A Escala de estadiamento da demência (CDR-DLFT) foi usada para confirmar a fase da doença. O Inventário Neuropsiquiátrico (INP) foi aplicado para investigar os problemas comportamentais. A Bateria de Avaliação Frontal (BAF) investigou as funções executivas. O Índice das Atividades de Vida Diária (Katz), Questionário para Avaliação da Comunicação Funcional na Afasia (QACFA) e a Escala de funcionalidade da deglutição (EFD) avaliaram as habilidades funcionais. O Questionário de Habilidades de Alimentação e Deglutição nas Demências (QHADD) avaliou as dificuldades na deglutição e alimentação. Resultados: Os grupos DFTvc e APP não mostraram diferença estatisticamente significante no MEEM, CDR e BAF. Os cuidadores dos pacientes com DFTvc apresentaram mais horas de cuidado por dia em comparação aos pacientes com APP (p<0,05). Os grupos diferiram na EFD (p < 0,05). As características comportamentais que foram significantes na comparação entre os grupos DFTvc e APP foram: delírio, desinibição, comportamento motor aberrante e distúrbios do sono(p < 0,05) e alucinação (p=0,01). Os pacientes com DFTvc tiveram mais problemas de deglutição do que os pacientes com APP, tais como: tosse e engasgos, dificuldade com alguma consistência alimentar e dificuldade com alimento específico. Os problemas de deglutição na DFTvc se correlacionaram com a funcionalidade, aspectos cognitivos (p < 0,05), com a função executiva e com o comportamento (p < 0,01). Na APP, o subtipo semântico apresentou mais problemas de deglutição, tais como: escape de saliva e comida da boca, múltiplas deglutições, atraso na iniciação da deglutição e engasgos, estas características se correlacionaram com a ansiedade (p < 0,01), apatia e comportamento motor aberrante (p=0,01). Os problemas do comportamento alimentar foram mais frequentes no subtipo logopênico e se correlacionaram com dificuldades de comunicação. Os principais fatores preditivos da piora da funcionalidade da deglutição foram: declínio funcional, alterações comportamentais e o comprometimento da comunicação. Os problemas de deglutição foram observados em todas as fases da demência. A BAF foi o único instrumento que não apresentou uma boa confiabilidade interna. Conclusão: Problemas na deglutição foram observados nas duas variantes desde os estágios iniciais da demência. As alterações comportamentais, cognitivas e funcionais, e dificuldades na comunicação comprometeram as fases antecipatória e preparatória oral da deglutição. Por causa destas alterações, os cuidadores tiveram dificuldade no gerenciamento da situação de alimentação. Nosso estudo desenvolveu questionários resumidos para avaliar a deglutição e a comunicação funcional / Introduction: Swallowing and its main characteristics are still unknown in frontotemporal dementia. Objectives: To characterize swallowing and feeding behavior of patients with frontotemporal dementia who have behavioral variant (bvFTD) and primary progressive aphasia (PPA). To characterize patients with FTD and their caregivers.To describe cognitive and behavioral aspects, functionalstatus, functional communication, and swallowing function in FTD.To describe swallowing problems and feeding behavior in bvFTD and PPA. To correlate cognitive and behavioral aspects, functional status, and communication with swallowing. To identify predictive factors associated with worsening of functionality of swallowing and feeding behavior in FTD. To evaluate the instruments used. To develop reduced versions of: \"Assessment of Feeding and Swallowing Difficulties in Dementia\" and \"Functional Outcome Questionnaire Aphasia\". Method: This study included 46 individuals with FTD in mild, moderate and severe phases, and their 46 caregivers. The Mini mental state examination (MMSE) and the Severe Mini mental state examination (SMMSE) were used to assess the cognitive aspects. The FTLD-modified Clinical Dementia Rating scale (FTLD-CDR) was used to confirm the stage of the disease. The Neuropsychiatric Inventory (NPI) was applied to investigate the behavioral problems. The Frontal Assessment Battery (FAB) investigated executive functions. The Index of Activities of Daily Living (Katz), Functional Outcome Questionnaire- Aphasia and Swallowing rating scale (SRE) evaluated the functional abilities. The Assessment of Feeding and Swallowing Difficulties in Dementia (QHADD) evaluated the difficulties in swallowing and feeding. Results: bvFTD and PPA groups showed no statistically significant difference in MMSE, CDR and FAB. Caregivers of patients with bvFTD had more hours of care per day compared to patients with PPA (p < 0.05). The groups differed in SRE (p < 0.05). The behavioral characteristics that were significant in the comparison between bvFTD and PPA groups were delirium, disinhibition, aberrant motor behavior and sleep disturbances (p < 0.05), and hallucinations (p = 0.01). Patients with bvFTD had more swallowing problems than patients with PPA, such as coughing and choking, difficulty with some food consistency and difficulty with specific food. Swallowing problems in bvFTD correlated with functionality, with the cognitive aspects (p < 0.05), with executive function and behavior (p < 0.01). In PPA, the semantic subtype showed more swallowing problems such as escape of saliva and food in mouth, multiple swallows, delay in initiation of swallowing and choking, these characteristics correlated with anxiety (p < 0.01), apathy and aberrant motor behavior (p = 0.01). The problems of feeding behavior were more frequent in logopenic subtype and correlated with communication difficulties. The major predictors of worsening of swallowing function were: functional decline, behavioral changes and impaired communication. Swallowing problems were observed at all stages of dementia. The BAF was the only instrument that had bad internal reliability. Conclusion: Swallowing problems were observed in the two variants from the early stages of dementia. Behavioral, cognitive and functional changes, and difficulties in communication compromised the anticipatory and oral preparatory phase of swallowing. Because of these changes, caregivers had difficulty in managing the feeding situation. Our study developed reduced versions of questionnaires to assess swallowing and functional communication

A doença de Wilson é um distúrbio da excreção biliar de cobre devido a um defeito na proteína ATP7B. Em caráter pioneiro na América do Sul, seqüenciou-se o gene ATP7B em 60 pacientes brasileiros pertencentes a 46 famílias; os resultados foram relacionados com aspectos demográficos e fenotípicos. Detectaram-se 25 mutações, 12 das quais novas. A 3402delC (34,8%) e a L708P (14,1%) ocorreu em 58,3% das famílias de São Paulo e em 44,4% das de Minas Gerais, respectivamente. As substituições novas, pesquisadas por RFLP ou PCR alelo-específica, não ocorreram em 60 indivíduos controle; portanto, não são polimorfismos comuns. O estudo comparativo de haplótipos dos portadores da L708P da coorte atual e de Gran Canaria sugeriu um efeito-fundador comum para ambos os grupos. O fenótipo variou amplamente para genótipos idênticos / ATP7B protein. As the first study of its kind in South America, the ATP7B gene was sequenced and the results were related to demographic and phenotypic aspects of 60 Brazilian patients, from 46 distinct families. Twenty-five mutations were detected, 12 of which are novel. The 3402delC (34.8%) and the L708P (14.1%) occurred in 58.3% of the families from Sao Paulo and in 44.4% of those from Minas Gerais, respectively. The novel substitutions were shown not to be common polymorphisms by RFLP or allele-specific PCR studies performed in 60 control subjects. Haplotype analysis comparing carriers of the L708P from this cohort study with patients from Gran Canary suggests the same founder-effect for both groups. Phenotype varied widely for identic genotypes.

Las enfermedades neurodegenerativas cursan con la degeneración y muerte de las neuronas las cuales son incapaces de suplir su propia muerte. Debido a esta característica enfermedades como el Alzheimer, el Parkinson o el Glaucoma no tienen cura en la actualidad. La retina es una proyección del sistema nervioso central (SNC) encapsulada en el globo ocular y aislada del resto del SNC, lo que la hace fácilmente accesible a la manipulación experimental. En este trabajo estudiamos las alteraciones funcionales de la retina con el electrorretinograma de campo completo (ERG), técnica basada en el registro de la respuesta eléctrica retiniana tras la presentación de un estímulo de luz homogéneo. Así hemos estudiado los efectos de la sección del nervio, del aumento de presión intraocular y de la fototoxicidad, dichas lesiones afectan selectivamente a determinadas poblaciones neuronales retinianas e imitan enfermedades neurodegenerativas como el Glaucoma o la Degeneración Macular Asociada a la Edad. / Neurodegenerative diseases are characterized by degeneration and death of neurons which are unable to recover after a given insult, thus impairing functional recuperation. Because of this, there is no cure for diseases such as Alzheimer, Parkinson or Glaucoma. The retina is a projection of the central nervous system (CNS) located in the eye and therefore, isolated from the rest of the CNS. This makes the retina a very good model for experimental manipulation. In this work we have studied the functional changes in the retina by full field electroretinograme (ERG). This technique records the electric response of the retina after presentation of homogeneous light stimuli. We have studied the effects that optic nerve sections, increase of the intraocular pressure and phototoxicity have on ERG recordings. These lesions impair selectively certain retinal neuronal populations and imitate neurodegenerative diseases as Glaucoma or Age-related Macular Degeneration.

Biological signal processing can help us gain knowledge about biological complexity, as well as using this knowledge to engineer better systems. Three areas are identified as critical to understanding biology: 1) understanding DNA, 2) examining the overall biological function and 3) evaluating these systems in environmental (ie: turbulent) conditions. DNA is investigated for coding structure and redundancy, and a new tandem repeat region, an indicator of a neurodegenerative disease, is discovered. The linear algebraic framework can be used for further analysis and techniques. The work illustrates how signal processing is a tool to reverse engineer biological systems, and how our better understanding of biology can improve engineering designs. Then, the way a single-cell mobilizes in response to a chemical gradient, known as chemotaxis, is examined. Inspiration from receptor clustering in chemotaxis combined with a Hebbian learning method is shown to improve a gradient-source (chemical/thermal) localization algorithm. The algorithm is implemented, and its performance is evaluated in diffusive and turbulent environments. We then show that sensor cross-correlation can be used in solving chemical localization in difficult turbulent scenarios. This leads into future techniques which can be designed for gradient source tracking. These techniques pave the way for use of biologically-inspired sensor networks in chemical localization.

Dissertation (Ph.D.)--University of South Florida, 2009. / Title from PDF of title page. Document formatted into pages; contains 164 pages. Includes vita. Includes bibliographical references.

No description available.