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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.
251

Pathogenicity determinants of Fusarium graminearum on wheat ears

Beacham, Andrew Mark January 2011 (has links)
Some specialist microbes can deploy a range of mechanisms to cause disease on one or more host plant species. To identify entirely new classes of pathogenicity and virulence factors, a bioinformatics-reverse genetics approach has been applied to a plant pathogen where near complete genomic sequence information was available. A genomic region was identified on chromosome 1 of the important cereal pathogen Fusarium graminearum that contains a significant grouping of homologues of known virulence genes. Targeted deletion of these genes revealed a role for the neutral trehalase (NTH1) and protein kinase A regulatory subunit (PKAR) genes in the rate of disease symptom spread by F. graminearum, in addition to the previously reported SNF1 Ser/Thr protein kinase and STE7 MAP kinase kinase genes. Subsequent investigation of further genes at this locality revealed the presence of a gene, here named Fusarium graminearum Contributor to Virulence 1 (FCV1), which represent a novel class of gene required for a full rate of symptom spread. Targeted deletion of FCV1 led to a reduced rate of disease development by F. graminearum on wheat ears and Arabidopsis floral tissue, but did not affect trichothecene mycotoxin production. The fcv1 deletion mutant also exhibits altered hyphal growth, reduced asexual sporulation and altered sensitivity to oxidative and osmotic stress. In the complemented strain, wild-type traits were completely or partially restored. This micro-region of < 40 kb containing these five important genes represents a novel type of gene cluster containing genes required for a full rate of disease development. This micro-region is located in a genomic region of low recombination, is highly conserved in three other Fusarium species, but is less conserved in other plant pathogenic species. The micro-region is not defined by a distinct GC content or coordinated gene expression patterns, nor is it flanked by highly repetitive sequences. This micro-region is distinct from the previously identified fungal and bacterial virulence gene clusters and the clustered biosynthesis-associated genes required to synthesis metabolites which contribute to pathogenicity. This method for novel disease development-contributing gene identification is applicable to any sequenced pathogen species.
252

Klassisk musik på gehör : En fenomenologisk självstudie / Classical music by ear : A phenomenological self-study

Söderqvist, Fanny January 2016 (has links)
Syftet med denna studie är att utforska och beskriva erfarandet av vad som sker i min livsvärld när jag arbetar med gehörsbaserad instudering av ett klassiskt stycke. För att uppnå syftet är följande forskningsfråga ställd: Hur erfars gehörsmässig inlärningsprocess av ett klassiskt violinstycke? Självstudien utgår från ett fenomenologiskt perspektiv. Utgångspunkt var ett klassiskt violinstycke som övades in under en period av 9 veckor. Stycket övades 3 gånger varje vecka och samtliga övningspass dokumenterades med loggbok. Ett övningspass i veckan filmades för att också observeras. Resultatet bygger på de återkommande mönster som framkom under analysen och beskrivs i tre faser: Första fasen - Övningsstrategier, Andra fasen – Svårigheter och avslutningsvis Tredje fasen – Lösningar. I diskussionen berörs teman som erfarandet av att lära in ett klassiskt stycke på gehör, inlärningsstrategier och förändrad livsvärld. / The purpose of this self-study is to explore and describe the experiences of studying a classical peace by ear. The perspective is the phenomenological life-world perspective. Starting point was a classical piece for violin which I practiced for a period of 9 weeks. The piece was practiced 3 times each week and all sessions were documented in a logbook. Once a week the pratice occasions was also filmed for video observation. The result is based on the patterns which appeard during the analysis and are presented in three phases: First phase-Practice strategies, Second phase-Difficulties and Third phase-Solutions. A discussion about experiences of learning a classic piece by ear, learning strategies and changes in the life-world are made in the last chapter.
253

Evolution des structures neurocrâniennes des Equoidea (Mammalia, Perissodactyla) européens paléogènes / Evolution of neurocranial structures of the paléogènes European Equoidea (Mammalia, Perissodactyla)

Danilo, Laure 20 December 2012 (has links)
La radiation adaptative des Equoidea est encore mal comprise en raison notamment de la méconnaissance de la phylogénie de cette super-famille. La principale irrésolution de ces relations de parenté porte sur les pachynolophes, Equoidea européens rapprochés des Equidae ou des Palaeotheriidae. Pendant une grande part de l'Éocène, l'Europe est isolée et subit à la fin de cette période de profonds changements climatiques. Lors de la Grande Coupure son isolement s'achève, tandis que l'aridité du climat s'installe, et des faunes migrantes provoquent l'extinction de nombreux groupes endémiques. Un Equoidea européen basal, richement représenté par un matériel bien préservé permet d'appuyer une des hypothèses phylogénétiques les plus récentes. Cependant, les caractères couramment utilisés pour débattre de cette question n'apportent pas de réponse claire et définitive. Aussi, cette étude se propose de mener des investigations sur des régions encore peu explorées de ces animaux comme le neurocrâne, grâce à la microtomographie (CT scan), qui permet un accès non destructif aux structures (encéphale, pétreux, labyrinthe osseux, sinus). Outre l'intérêt phylogénétique, ces organes peuvent, de par leurs fonctions, receler un intérêt paléoécologique. Jusqu'à présent, peu d'études à large échelle ont porté sur ces structures chez les Perissodactyla, s'agissant pour la plupart de mentions anecdotiques. Comme préalable indispensable, une étude modèle a été réalisée sur un Equidae sauvage actuel afin de mieux appréhender la variabilité de ces structures méconnues. Pour la première fois, un large échantillon d'Equoidea européens a été scanné et leurs structures neurocrâniennes reconstruites en trois dimensions virtuelles. Ce sont au total 20 espèces qui ont été échantillonnées, couvrant l'évolution de ces animaux de leur origine à leur extinction, pendant plus de 20 millions d'années. Leurs crânes ont été scannés, leurs structures internes reconstruites, comparées et analysées au moyen de la cladistique. Une nouvelle hypothèse phylogénétique propose des relations de parenté intra-Equoidea et montre la pertinence des caractères neurocrâniens, tout en conduisant à envisager une étude plus vaste. Les Palaeotheriidae apparaissent comme un groupe très diversifié, notamment au regard des Equidae éocènes d'Amérique du Nord, et caractérisé par une évolution en mosaïque. Ils connaissent une évolution cérébrale précoce par rapport aux faunes contemporaines (Equidae, Cetartiodactyla, Carnivora), ce qui, via le développement de nouvelles stratégies adaptatives, pourrait expliquer partiellement cette grande diversification familiale. Un parallèle est envisagé avec l'évolution endémique des Notoungulata, qui semblent eux aussi montrer une complexification cérébrale précoce. Cependant, face à un environnement biotique et abiotique bouleversé (fin de l'Éocène et lors de la Grande Coupure), ces structures complexes impliquant un coût métabolique important et une trop grande spécialisation, avec en conséquence, moins de potentiel adaptatif, auraient pu les désavantager et les conduire à l'extinction. / The Equoidea adaptive radiation still remains badly known, especially due to the ignorance of their phylogeny. The main indecision of these relationships concerns the pachynolophs, European Equoidea either approached to the Equidae or to the Palaeotheriidae. During a great part of the Eocene times, Europe was isolated, and, at the end of this period, has undergone strong climatic changes. That isolation ended at the « Grande Coupure » event, whereas an arid climate moved, and migrant faunas caused the extinction of many endemic groups. A basal European Equoidea, richly represented by well-preserved material, can support one of the latest phylogenetic hypotheses. However, commonly used characters to discuss this issue do not provide a clear and definitive answer.Therefore, this study aims to investigate on unexplored regions of these animals as the neurocranium through microtomography (CT), which allows access to non-destructive structures (brain, petrosal, bony labyrinth, and sinus).Furthermore phylogenetic interest these bodies may, through their functions, harbor paleoecological interest. Until now, few large-scale studies have focused on those structures in the Perissodactyla, with regard to most were anecdotal reports. As a prerequisite, a model study was performed on a wild current Equidae to better understand the variability of these unknown structures. For the first time, a large sample of European Equoidea has been scanned and their neurocranium structures virtually reconstructed in three-dimensions. A total of 20 species were sampled, covering the evolution of these animals from their origin to their extinction, for over 20 million years. Their skulls were scanned; their internal structures reconstructed compared and analyzed using cladistics. A new phylogenetic hypothesis provides intra Equoidea relationships and shows the relevance of neurocranium characters, while driving to consider a larger study. The Palaeotheriidae appears as a highly diverse group, particularly with regard to Eocene Equidae in North America, and characterized by a mosaic evolution. Their brain evolved earlier than that of contemporary faunas (Equidae, Cetartiodactyla, Carnivora); which may partially explain the strong diversification of that family, through the development of new adaptive strategies.
254

Classification of Receptor-Like Cytoplasmic Kinases in Maize and Functional Analysis of ZmBLK1

Weiran Li (7036880) 14 August 2019 (has links)
Receptor-like cytoplasmic kinases (RLCKs) form a large family of proteins in plants. RLCKs have been found in different plant species, regulating plant immunity to different bacterial and fungal pathogens. Previous studies implicated <i>Arabidopsis</i> <i>botrytis induced kinase1 (BIK1)</i> and <i>tomato protein kinase 1b (TPK1b)</i> in plant resistance to <i>Pseudomonas syringae</i> and <i>Botrytis cinerea</i>. In this study, we classified 195 putative maize RLCKs into ten subfamilies. Based on the amino acid sequence similarity to BIK1 and TPK1b, a novel maize RLCK,<i> zea mays bik1-like kinase 1 (ZmBLK1)</i> was identified. Enzyme assays with cloned <i>ZmBLK1</i> revealed a functional kinase when expressed in planta. The recombinant protein located to the plasma membrane. Expression of <i>ZmBLK1</i> is highest in maize leaves compared to other structures at silking stage. Expression of the recombinant <i>ZmBLK1</i> significantly reduced the rate of lesion spread in maize leaves inoculated with the Goss’s wilt pathogen. In maize kernels, expression of <i>ZmBLK1</i> increases during kernel maturation. Kernels from transgenic maize overexpressing <i>ZmBLK1</i> were not resistant to <i>Aspergillus flavus</i> or to aflatoxin contamination. In addition, mutations were made in <i>ZmBLK1</i> that were hypothesized to create a constitutively active kinase. However, resulting proteins had similar activity to the wild-type ZmBLK1 and transgenic plants showed similar responses to the Goss’s wilt and Aspergillus ear rot pathogens. Overall, this research established the first characterization of RLCKs in maize and described a potential contribution of ZmBLK1 to maize immune responses.
255

Jovem doutor: promoção da saúde auditiva e inclusão do deficiente auditivo com malformação de orelha externa e/ou média / Young doctor: promote hearing health and the inclusion of deaf malformation with external and/or middle ear

Oliveira, Valdéia Vieira de 12 December 2012 (has links)
As malformações de orelha são anomalias que ocorrem no período de desenvolvimento embrionário e podem acometer a orelha externa, média e/ou interna, podendo ser uni ou bilaterais. Na fase escolar, crianças com malformação de orelha podem ser prejudicadas pela falta de estímulos adequados ao seu potencial cognitivo, socioafetivo, linguístico e politicocultural, acarretando prejuízo considerável ao desenvolvimento da aprendizagem. Nesse contexto, esta pesquisa teve como objetivo desenvolver um programa para alunos do ensino fundamental, utilizando a teleducação interativa do Projeto Jovem Doutor, visando a promoção da saúde auditiva e a inclusão do deficiente auditivo com malformação de orelha externa e/ou média, no âmbito escolar. O estudo foi dividido em duas fases. A primeira fase foi constituída pela construção de um conteúdo educacional (roteiro), avaliação por juízes da área de Fonoaudiologia, por meio de dois questionários e adequação de acordo com as sugestões dos juízes. A segunda fase constituiu da aplicação do conteúdo para 18 alunos sem malformações craniofaciais, deficiência auditiva, visual ou intelectual, utilizando a metodologia do Projeto Jovem Doutor e foi dividida em: atividade presencial informando a dinâmica do curso e introdução do tema; etapa não presencial, com apresentação on-line do roteiro e etapa presencial, para estabelecer estratégias de repassar o conteúdo aos colegas e comunidade. Anteriormente e após a aplicação do programa de capacitação, os alunos responderam ao Questionário Situação-Problema (QSP), com o objetivo de mensurar o conhecimento teórico prévio e o adquirido ao longo do programa. Posteriormente, responderam a outros dois, denominados Questionário Opinião - (QO), com o objetivo de expressar a opinião sobre o curso à distância e a Ficha de Pesquisa Motivacional - (FMP), para verificar subjetivamente os aspectos motivacionais do programa de capacitação. Os professores também avaliaram o exercício das habilidades sociais dos alunos, por meio do Questionário de Crenças e Sentimentos do Professor (CSP). Os resultados mostram que a maioria dos juízes apresentou apreciações positivas, considerando a qualidade do roteiro como excelente (1789 respostas) e muito boa (911 respostas). Em relação ao QSP, os resultados apontaram que, comparando, estatisticamente, o antes (pré-teste) e o depois (pós-teste), os resultados apontaram que metade dos pesquisados acertou até 40% no pré-teste e metade acertou até 80% no pós-teste. Assim, os dados apresentados revelam que a aplicação do programa produziu efeito positivo em relação ao aumento dos conhecimentos dos alunos. Em resposta ao QO, a maioria dos alunos apresentou opinião positiva em relação ao curso, revelando índice de alta aprovação. A análise da FMP apontou alto índice de satisfação motivacional com o programa, por parte dos alunos, considerando-o impressionante. No questionário CSP, as professoras atribuíram alta importância para o repertório de habilidades sociais, enquanto possível fator, tanto do desenvolvimento socioemocional dos alunos, como do desempenho. Concluiu-se que a implementação do programa visando a promoção da saúde auditiva e a inclusão do deficiente auditivo com malformação de orelha externa e/ou média, no âmbito escolar, foi viável para os participantes, porém sugere-se reaplicação a outros escolares. / The ear malformations are abnormalities that occur during embryonic development and can affect the outer ear, middle and/or internal, may be unilateral or bilateral. At school age children with ear malformations may be impaired by lack of appropriate incentives to its potential cognitive, socio-emotional, linguistic, political and cultural, causing considerable damage in the development of learning. In this context, this study aimed to develop a program for elementary school students using the interactive tele-education Project Young Doctor aiming to promote hearing health and the inclusion of deaf ear malformation with external and / or middle ear in the school. The study was divided into two phases. The first phase was formed by the construction of an educational content (screenplay), evaluation by judges from the area of Audiologist, through two questionnaires and adequacy in accordance with the suggestions of the judges. The second phase consisted of applying content to 18 students without craniofacial malformations, hearing impairment, visual or intellectual, using the methodology of the project and Dr. Young was divided into: classroom activity informing the dynamics of the course and introduction to the subject; step without attending, online presentation of the script and stage presence to establish strategies to pass content to colleagues and community. Before and after the implementation of the training program the students responded to the \"Questionário Situação Problema - (QSP)\" with the objective of measuring the theoretical knowledge acquired prior and during the program. And then the other two called \"Questionário Opinião (QO)\" with the aim of expressing student opinion about the distance course and \"Ficha de Pesquisa Motivacional (FMP)\" to subjectively evaluate the motivational aspects of the training program. Teachers also evaluated whether there were changes in student behavior through the \"Crenças e Sentimentos do Professor (CSP).\" The results show that most of the judges had positive assessments, considering the quality of the script as \"excellent\" (1789 responses) and \"very good\" (911 responses). Regarding the QSP results indicate that, comparing statistically the before (pretest) and after (post-test) results showed that half of respondents agreed and 40% in the pre-test and half to hit 80% in post-test. Thus, the data presented show that the implementation of the program has produced positive effect in relation to the increased knowledge of the students. In response to QO, most students showed a positive opinion about the course, revealing high approval rate. The analysis of FMP pointed motivational high level of satisfaction with the program, by the students, considering it as \"impressive\". In the questionnaire CSP teachers assigned high importance to the repertoire of social skills as much as possible factor in socio-emotional development of students as performance. It was concluded that the implementation of the program aimed at promoting hearing health and the inclusion of deaf ear malformation with external and / or average in the school was viable for those students, but it is suggested reapplying to other schools.
256

Padrão de análise da timpanometria com sonda de 226 Hz na criança considerando a pressão do pico de máxima compliância e a compliância estática / Tympanometry analysis standard with 226 Hz of age six months to three years considering the pressure of the peak of maximum compliance and the static compliance

Melo, Alana Ribeiro de 08 May 2017 (has links)
A análise precisa dos resultados da timpanometria é essencial para determinar a condição da orelha média, principalmente em crianças nos primeiros anos de vida. Assim, o objetivo deste estudo foi apresentar um padrão de análise da timpanometria com sonda de 226 Hz para a faixa etária de seis meses a três anos, considerando a pressão do pico de máxima compliância e a compliância estática. Foram analisados prontuários de crianças de seis meses a três anos de idade atendidas no período de outubro de 2012 a fevereiro de 2016 no Centro de Pesquisas Audiológicas - Seção de Implante Coclear do Hospital de Reabilitação de Anomalias Craniofaciais e na Clínica de Audiologia Infantil da Clínica de Fonoaudiologia da Faculdade de Odontologia de Bauru, ambos da Universidade de São Paulo. A casuística foi dividida em dois grupos: grupo sem alteração de orelha média, composto por 224 orelhas, e o grupo com alteração de orelha média, composto por 59 orelhas. Foram considerados para análise os valores de pressão do pico de máxima compliância (daPa) e de compliância estática (ml) obtidos na timpanometria com sonda de 226Hz. No grupo sem alteração, o Teste Correlação Mann Whitney revelou que não houve diferença significante entre os sexos para pressão do pico de máxima compliância (p=0,782) e para a compliância estática (p=0,085). Também não houve correlação dos valores de pressão (p=0,678) e compliância (p=0,079) com a idade, de acordo com o Teste Correlação de Spearman. Considerando o intervalo entre os percentis 2,5 e 97,5 obtidos para a pressão e compliância nos grupos sem e com alteração, observou-se uma faixa de valores comum aos dois grupos, ou seja, os valores contidos nesta faixa não conseguiram classificar a orelha média como normal ou alterada. De acordo com os percentis 2,5 e 97,5, foi possível estabelecer uma faixa de normalidade para a pressão do pico de máxima compliância, de +52 daPa a -100 daPa, e para compliância estática, de 0,20 ml a 0,68 ml. Enquanto que na faixa de alteração, os valores variaram de -259 a 17,52 daPa para pressão e de 0,04 a 0,41 ml para a compliância. Assim, uma faixa de intersecção foi identificada, correspondente ao intervalo de -100 a 17,52 daPa para pressão do pico de máxima compliância e de 0,2 a 0,41 ml para a compliância estática. A análise dos dados demonstrou que a timpanometria com sonda de 226 Hz apresentou alta sensibilidade e baixa especificidade na faixa etária de seis meses a três anos. / Accurate analysis of tympanometry results is essential to determine the condition of the middle ear, especially in children in their first years of life. Thus, this study aimed at presenting a standard analysis of tympanometry with a 226 Hz probe for the age range six months to three years, taking into account the pressure of the peak of maximum compliance and static compliance. The records of 6-month to three-year old children assisted from October 2012 to February 2016 at the Audiology Research Center - Cochlear Implant Section of the Craniofacial Anomalies Rehabilitation Hospital and at the Children\'s Audiology Clinic of the Audiology and Speech-Language Pathology Clinic of the Bauru Dentistry School, both of the University of São Paulo, were analyzed. The sample was divided into two groups: a group with no middle ear alteration comprising 224 ears and the group with middle ear alteration composed of 59 ears. For analysis, the pressure values of the maximum compliance peak (daPa) and static compliance (ml) obtained in the tympanometry with a 226Hz probe were considered. In the group with no alteration, the Mann Whitney Correlation Test showed no significant difference between the genders for the maximum compliance peak pressure (p = 0.782) and for static compliance (p = 0.085). No difference was seen, either, for pressure (p = 0.678) and compliance (p = 0.079) values, according to age, by using the Spearman Correlation Test. Considering the interval between percentiles 2,5 and 97,5 obtained for pressure and compliance in the groups without and with alteration, a range of values common for the two groups was observed, that is, the values contained in this range could not classify the Middle ear as normal or altered. According to percentiles 2,5 and 97,5, it was possible to establish a range of normality for the pressure of the maximum compliance peak, from +52 daPa to -100 daPa, and for static compliance, from 0.20 ml to 0.68 ml, while in the alteration range, values ranged from -259 to 17,52 daPa for pressure and from 0,04 to 0,41 ml for compliance. Thus, an intersection range was identified, corresponding to the interval of -100 to 17,52 daPa for the pressure of the maximum compliance peak and 0,2 to 0,41 ml for the static compliance. Data analysis showed that tympanometry with a 226 Hz probe presented high sensitivity and low specificity in the 6-month to 3-year age range.
257

Timpanometria em lactentes utilizando sonda de multifrequência / Multifrequency tympanometry in infants

Moraes, Tâmyne Ferreira Duarte de 28 February 2011 (has links)
O objetivo deste trabalho foi realizar a caracterização das medidas de imitância acústica de lactentes de zero a três meses de idade utilizando timpanometria de multifrequência. Foram avaliados 54 lactentes sem queixas auditivas e com presença de emissões otoacústicas evocadas transientes, por meio de entrevista audiológica, inspeção visual do meato acústico externo e medidas de imitância acústica nas frequências de 226Hz, 678Hz e 1000Hz, coletando-se os registros timpanométricos relacionados ao efeito de oclusão, à forma da curva timpanométrica, à pressão de pico timpanométrico, ao volume equivalente do meato acústico externo e ao pico compensado da admitância acústica estática. Os resultados indicaram presença de efeito de oclusão nas três frequências: 2,88% em 226Hz; 4,81% em 678Hz e 3,85% em 1000Hz; predomínio de curva timpanométrica em pico único (65,35% em 226Hz, 81,82% em 678Hz e 77,00% em 1000Hz); pressão de pico timpanométrico variando de -150 a 180daPa, com valores considerados normais; aumento do volume equivalente do meato acústico externo com aumento da frequência da sonda (0,64ml em 226Hz, 1,63mmho em 678Hz e 2,59mmho em 1000Hz), assim como os valores do pico compensado da admitância acústica estática (0,51ml em 226Hz, 0,55mmho em 678Hz e 1,20mmho em 1000Hz). Foram classificados como normais 93,06% dos timpanogramas realizados com 226Hz, 80,81% em 678Hz e 82,00% em 1000Hz. Por meio destas avaliações e resultados encontrados foi possível caracterizar as medidas de imitância acústica dos lactentes. / The aim of this study was to characterize acoustic immittance measures of infants from zero to three months of age using multifrequency tympanometry. 54 infants without hearing complaint and with transient evoked otoacoustic emissions presence were evaluated by an audiologic interview, a visual inspection of the ear canal and measures of acoustic immittance in the frequencies of 226Hz, 678Hz and 1000Hz, where tympanometric records of the occlusion effect, tympanometric curve type, tympanometric peak pressure, equivalent ear canal volume and peak compensated static acoustic admittance were collected. The results indicated presence of occlusion effect in three frequencies: 2.88% at 226Hz, 4.81% at 678Hz and 3.85% at 1000Hz; predominance of tympanometric curve with single peak ( 65.35% at 226Hz, 81.82% at 678Hz and 77.00% at 1000Hz), tympanometric peak pressure ranging from -155 to 180daPa with normal limits, equivalent ear canal volume increase with the frequency of the probe increase (0.64ml at 226Hz, 1.63mho at 678Hz and 2.59mmho at 1000Hz) and the increase of the peak compensated static acoustic admittance values with the frequency increase (0.51ml at 226Hz, 0.55mmho at 678Hz and 1.20mmho at 1000Hz). 93.06% of tympanograms were classified as normal at 226Hz, 81.82% at 678Hz and 77.00% at 1000Hz. Considering these evaluations and results it was possible to characterize the acoustic immittance measures of infants.
258

"Análise comparativa entre sistemas de retenção para próteses auriculares implanto-retidas" / Comparative analyses between retentive systems for implant-retained ear prosthesis

Sousa, Andréa Alves de 03 May 2006 (has links)
As próteses auriculares retidas por meio de implantes osseointegráveis proporcionam maior segurança e conforto, melhorando a qualidade de vida dos pacientes. Este trabalho avalia comparativamente a força de resistência à tração dos sistemas de retenção barra/2 clipes, barra/3 clipes, 2 magnetos, e 3 magnetos, empregados para retenção de prótese auricular. Os sistemas de retenção foram submetidos à ciclagem mecânica, com intervalos de 540 ciclos de inserção e remoção para a simulação de períodos de uso clínico, até um total de 3240 ciclos, sendo, a cada intervalo, submetidos ao ensaio mecânico para força de resistência à tração. Os resultados indicam que os sistemas barra/clipes proporcionam maiores retenções do que os sistemas com magnetos e ao mesmo tempo em que a ciclagem mecânica não interfere na relação entre o número de elementos retentores e a retenção proporcionada dentro dos sistemas barra/clip e dos sistemas magnetos. O sistema barra/2 clipes sofre uma perda significantemente maior da capacidade de retenção frente à ciclagem mecânica, sugerindo uma menor longevidade clínica. A relação da capacidade de retenção entre os sistemas não se altera com a ciclagem mecânica uma vez que, a retenção proporcionada pelo sistema barra/3 clipes mantém-se superior, indicando uma maior durabilidade clínica. As retenções proporcionadas pelos sistemas barra/2 clipes e 3 magnetos, bem como aquelas proporcionadas pelos sistemas 2 e 3 magnetos não diferem ao final da ciclagem mecânica, indicando uma durabilidade clínica semelhante. / Placement of osseointegrated implants for retention of ear prosthesis provides greater security and comfort, improving the quality of life of the patients. This work evaluates and compares the retentive mechanical behavior of bar/2 clips, bar/3 clips, 2 magnets, and 3 magnets retention systems, used for implant-retained ear prosthesis. The systems were submitted to mechanical cycling , with intervals of 540 cycles of insertion and removal, for the simulation of clinical periods of function, up to 3240 cycles, being submitted to the mechanical forces essay at each interval. Data were subjected to Tukey-Kramer procedure and the comparative analyses indicate that the bar/clips systems provide different and better retentive forces than the magnet systems and mechanical cycling does not alter the numerical relative performance of the retainer components within the bar/clip or magnet retention system. The bar/2 clips system shows the biggest and statistically significant loss of the retentive forces during mechanical cycling (p<0,05), suggesting a shorter clinical life. The retention provided by the bar/3 clips system remains superior after mechanical cycling, indicating a longer clinical life. The relation between the retention forces presented within the bar/clip systems and magnets systems does change under mechanical cycling. Also, the relation between the bar/2 clips system and 3 magnets system, as well as between 2 and 3 magnets systems do not differ at the end of mechanical cycling , indicating a similar behavior toward clinical life.
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Medidas de imitância acústica de banda larga em indivíduos com otosclerose / Wideband acoustic immittance measurements in subjects with otosclerosis

Chaves, Juliana Nogueira 29 March 2017 (has links)
Na prática clínica, nota-se uma dificuldade em identificar a rigidez do sistema tímpano-ossicular decorrente da Otosclerose por meio dos métodos de avaliação rotineiramente empregados. Assim, as medidas de imitância acústica de banda larga podem fornecer mais informações sobre a condição do sistema tímpano-ossicular por avaliarem uma ampla faixa de frequência. O objetivo do estudo foi caracterizar as medidas de imitância acústica de banda larga com os estímulos tom puro e chirp em indivíduos com diagnóstico de Otosclerose submetidos à estapedectomia ou estapedotomia. Foram avaliados 40 indivíduos na faixa etária de 33 a 80 anos, totalizando 54 orelhas operadas e 22 orelhas não operadas. A avaliação audiológica foi realizada por meio da otoscopia, audiometria tonal liminar, logoaudiometria e imitanciometria. As medidas de imitância acústica de banda larga foram obtidas por meio do sistema de medidas Middle-Ear Power Analyzer MEPA3, versão 5.0 (Mimosa Acoustics), utilizando os estímulos tom puro e chirp. Os dados obtidos foram submetidos à análise estatística descritiva e inferencial, com nível de significância de 0,05. As orelhas com Otosclerose apresentaram maior absorvância em 750 Hz, uma tênue diminuição até 3000 Hz, acentuando-se a partir desta frequência. A magnitude da admitância foi maior na faixa de frequência de 1992 a 4008 Hz, assim como a magnitude da impedância foi maior nas frequências baixas com diminuição até 4008 Hz e aumento em 6000 Hz. Estas orelhas foram dominadas pela rigidez nos sons graves e médios, por resistência entre 3000 e 4008 Hz e a partir desta frequência pela massa. A fase da impedância foi maior em 258 Hz e o delay da reflectância (slope) apresentou uma variação de comportamento entre as frequências, não sendo possível caracterizar um padrão de resposta. Conclui-se que há diferenças nas medidas obtidas nas orelhas com Otosclerose submetidas à cirurgia, quando analisadas as frequências baixas e médias, o que demonstra o impacto positivo da intervenção cirúrgica na funcionalidade do sistema tímpano-ossicular. / In clinical practice, there is a difficulty in identifying the rigidity of the tympano-ossicular system resulting from Otosclerosis through the routinely employed evaluation methods. Thus, wideband acoustic immitance measurements can provide more information on the condition of the tympanic-ossicle system by evaluating a wide frequency range. This study aimed at characterizing the wideband acoustic immitance measurements with the pure tone and chirp stimuli in individuals diagnosed with Otosclerosis submitted to stapedectomy or stapedotomy. Forty individuals aged 33 to 80 years were evaluated, totaling 54 operated and 22 non-operated ears. Audiology assessment was performed through otoscopy, pure-tone audiometry, logoaudiometry and imitanciometry. Wideband acoustic immitance measurements were obtained using the Middle-Ear Power Analyzer (MEPA3), version 5.0 (Mimosa Acoustics), by means of pure tone and chirp stimuli. Data were submitted to descriptive and inferential statistical analysis, with a significance level of 0.05. The ears with Otosclerosis presented a greater absorbance in 750 Hz, a slight diminution until 3000 Hz, being accentuated from this frequency. The admittance magnitude was higher in the frequency range from 1992 to 4008 Hz, as well as the impedance magnitude was higher in the low frequencies with a decrease up to 4008 Hz and an increase in 6000 Hz. These ears were dominated by rigidity in the low and medium sounds, by resistance between 3000 and 4008 Hz, and from this frequency, by the mass. The impedance phase was higher at 258 Hz and the reflectance delay (slope) showed a behavioral variation between the frequencies, a response not being characterized. It can be concluded that there are differences in the measurements obtained in Otosclerosis ears submitted to surgery, when the low and medium frequencies were analyzed, which demonstrates the positive impact of the surgical intervention on the tympano-ossicle system.
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Herstrukturering van persentasie gehoorverlies bepaling

Bronkhorst, Johannes Petrus January 2011 (has links)
Thesis (MTech (Omgewingsgesondheid))--Cape Peninsula University of Technology, 2011. / Occupational related diseases (ORD) which result in permanent disability are compensable in South Africa. During the 2005/6 – 2007/8 financial years compensation for ORD’s totalled approximately R200 million per annum of which this study indicated, R92 milllion on average possibly related to hearing loss. This expense must surely result in negative financial consequences for both the South African government and employers. The manner in which compensation for hearing loss relating to the work place, is to be determined, was changed by Instruction 171 published in the Government Gazette dated 16 November 2001. A baseline audiogram is required for every employee who enters a noise zone during the course of employ and Instruction 171 specified that the percentage hearing loss has to be used to determine this baseline audiogram. A baseline audiogram, which is valid for the total working career of an employee, is used to monitor the hearing status of employees for purposes of possible future compensation. It consequently serves as a reference point from which hearing threshold shifts (HTS) are determined. The significance of the accuracy of this test is thus evident.Prior to the implementation of Instruction 171, various audiometric measuring tools were, in accordance with South African Standards, used in industry for purposes of hearing conservation. These measuring tools referred to above were used for various purposes which included, the determination of; compensable HL, the need for diagnostic procedures, when HL had to be reported to the Department of Labour as “an incident” and the efficiency of a hearing conservation program. With implementation of Instruction 171, these various measuring tools were reduced to a single tool namely the PLH.Naturally the accuracy of PLH determination is also important to employees as it may affect possible compensation of an individual’s hearing loss. Considering the significance of baseline audiograms for purposes of compensation, the following questions arose in this study; (i) does PLH, in its current format, measure the hearing threshold (HT) sufficiently accurately to (a) establish the baseline audiogram, (b) monitor HL for purposes of compensation, and (ii) is the PLH, as currently determined, suitable to identify further diagnostic procedures for purposes of hearing conservation?A more accurate PHL calculation procedure would be to the advantage of all parties concerned. A database which included baseline audiograms of 1101 respondents was studied to determine if the PLH, in its current format, was suitable to comply with the needs pertaining to industrial audiometry. The respondents were employees working in noise zones at various industries, located in the Western Cape and were all tested in accordance with South African audiometry standards.The current PLH determination procedure was studied and current audiometry baseline test results were reconstructed in a manner to calculate an alternative PLH. This reconstructed PLH was consequently used to determine a new B-baseline audiogram. StatSoft Statistica, software was used to statistically compare the current baseline audiogram with the B-baseline audiogram. The study revealed that the B-baseline audiogram succeeded to on average produce a 17% improvement (more accurate) in the determination of the PLH. The PLH of the B-baseline audiogram can thus be regarded as more representative of the true HT of employees.Based on the results of this study it is recommended that the current determination of the PLH used to establish the baseline, be amended. The proposed amendment (B-baseline audiogram) still uses the HT of the two tests done in accordance with Instruction 171 and no amendment of the test procedure is thus required. As the PLH of the baseline and the diagnostic baseline audiogram is currently used for compensation purposes, it is recommended that the B-baseline method be used for both the baseline and diagnostic baseline audiograms.

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