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Efeito da irrigação e medicação endodôntica em dentina infectada por biofilmes oraisZapata, Ronald Ordinola 07 June 2013 (has links)
O objetivo desse estudo foi avaliar o efeito antimicrobiano da irrigação e da medicação endodôntica em dentina infectada por biofilmes orais. Na primeira parte do estudo, avaliaram-se as seguintes soluções irrigadoras: hipoclorito de sódio a 1%, clorexidina a 2%, ácido cítrico a 10% e EDTA a 17%. Na segunda parte, avaliaram-se soluções irrigadoras contendo associações (MTAD, Smear Clear, Qmix, ácido maleico a 7%, iodo-iodeto de potássio a 2% e ácido peracético a 4%), sendo essas soluções comparadas a 2 concentrações de hipoclorito de sódio. Na terceira parte, avaliou-se o efeito de dispositivos sônicos, ultrassônicos e de laser na capacidade de limpeza do hipoclorito de sódio a 6%, com uso de microscópio eletrônico de varredura. Na quarta parte, avaliaram-se os efeitos antimicrobianos de 3 pastas de hidróxido de cálcio contendo 3 radiopacificadores diferentes (óxido de zinco, sulfato de bário e iodofórmio). No último experimento, foram avaliadas as propriedades antimicrobianas da pasta triantibiótica, da clorexidina em gel e da pasta aquosa de hidróxido de cálcio. Os resultados mostraram que todas as soluções de hipoclorito de sódio testadas e o ácido peracético a 4% foram mais efetivas sobre o biofilme em comparação a todos os irrigantes testados. As soluções de hipoclorito de sódio propiciaram significativamente uma melhor limpeza da dentina. O ácido peracético foi também efetivo para dissolver células do biofilme. A ativação do hipoclorito de sódio com o ultrassom e com laser interferiu favoravelmente na limpeza da dentina infectada. A pasta triantibiótica e o hidróxido de cálcio associado ao iodofórmio foram os medicamentos mais efetivos na descontaminação da dentina infectada. Portanto, o protocolo ideal que deve ser adotado para garantir uma descontaminação efetiva da dentina contaminada por biofilmes orais inclui o uso de hipoclorito de sódio ativado por ultrassom ou laser e medicação intracanal de hidróxido de cálcio com iodofórmio. O ácido peracético e a pasta triantibiótica apresentaram resultados promissores. / The aim of this study was to evaluate the antimicrobial effect of endodontic irrigation and medication on biofilm infected dentin. In the first part, we evaluated the following irrigant solutions: 1% sodium hypochlorite, 2% chlorhexidine, 10% citric acid and 17% EDTA. In the second part, irrigant solutions containing combinations of antimicrobials such as \"MTAD,\" \"Smear Clear\", \"Qmix\", 7% maleic acid and 2% iodine-potassium iodide and 4% peracetic acid were evaluated. These solutions were compared to 2 concentrations of sodium hypochlorite. In the third part, we evaluated the effect of sonic, ultrasonic and laser irrigation on the cleaning ability of biofilm infected dentin using 6% sodium hypochlorite under scanning electron microscope. In the fourth part, we evaluated the antimicrobial effects of 3 calcium hydroxide pastes containing 3 different radiopacifiers (zinc oxide, barium sulfate and iodoform). In the last experiment, we evaluated the antimicrobial properties of the triantibiotic paste, 2% chlorhexidine gel and calcium hydroxide paste. The results showed that the sodium hypochlorite and the peracetic acid solutions were more effective to decontaminate the biofilm infected dentin in comparison to all of the tested irrigants. The sodium hypochlorite solutions allowed significantly better cleaning of the dentine. The peracetic acid was also effective to dissolve the biofilm cells. Activation of 6% sodium hypochlorite with ultrasonic and laser increased the cleaning of biofilm infected dentin. The triantibiotic paste and calcium hydroxide associated to iodoform were the most effective intracanal dressings available for the decontamination of the infected dentin. Therefore, the ideal protocol to be adopted in order to ensure an effective decontamination of biofilm infected dentin includes the use of sodium hypochlorite, specially activated by ultrasound or laser; and the use of calcium hydroxide with iodoform intracanal dressing. The peracetic acid and the triantibiotic paste also showed promising results.
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Avaliação das soluções irrigadoras da \"smear layer\" nos diversos níveis do conduto radicular com e sem o uso do ultra-som: estudo em microscopia eletrônica de varredura / Evaluation of irrigating solutions on smear layer removal at different levels of root canal with and without ultrasonics: a scanning electron microscopic studyRodrigues, Clarissa Teles 27 May 2011 (has links)
Este estudo teve como objetivo avaliar a capacidade de remoção da smear layer das paredes de canais radiculares instrumentados pelas soluções de soro fisiológico, EDTA a 17%, vinagre de maçã e SmearClear®, nos três níveis radiculares, associadas ou não ao ultra-som. Para tal propósito, foram utilizados 70 dentes caninos humanos superiores e inferiores extraídos os quais tiveram suas coroas removidas. O comprimento de trabalho foi determinado pela visualização da ponta de uma lima tipo K com diâmetro 10 no forame apical, subtraindo-se 1 milímetro dessa medida. Para o preparo biomecânico, instrumentou-se os dentes com o sistema rotatório ProTaper®, pela técnica coroa-ápice, até o instrumento F5, irrigando os canais com hipoclorito de sódio a 2,5% a cada troca de instrumento. Os dentes foram divididos aleatoriamente em 6 grupos de 10 dentes e 2 grupos controle de 5 dentes de acordo com o método de irrigação final a serem testados: Grupo 1 (controle) Soro fisiológico por 3 minutos sem ultra-som; Grupo 2 - (controle) Soro fisiológico por 3 minutos, sendo o primeiro minuto ativado pelo ultra-som; Grupo 3 - EDTA a 17% por 3 minutos sem ultra-som; Grupo 4 - EDTA a 17% por 3 minutos, sendo o primeiro minuto ativado pelo ultra-som; Grupo 5 - Vinagre de maçã por 3 minutos sem ultra-som; Grupo 6 - Vinagre de maçã por 3 minutos, sendo o primeiro minuto ativado pelo ultra-som; Grupo 7 - SmearClear® por 1 minuto sem ultra-som; Grupo 8 - SmearClear® por 1 minuto ativado pelo ultra-som. Em seguida, os dentes foram irrigados com hipoclorito de sódio a 2,5% e soro fisiológico e secos com cones de papel absorvente. As raízes foram seccionadas longitudinalmente e preparadas para a microscopia eletrônica de varredura com o aumento de 750 vezes. Fotomicrografias foram obtidas dos terços cervical, médio e apical e analisadas por três examinadores para a atribuição de escores para posterior análise estatística. Concluiu-se que as soluções de EDTA e SmearClear® foram efetivas na remoção da smear layer do canal radicular, com pequena vantagem numérica do EDTA, entretanto, sem diferença estatisticamente significante entre elas. O soro fisiológico apresentou resultado significativamente inferior comparado às demais soluções irrigadoras. O vinagre de maçã se mostrou ligeiramente inferior ao SmearClear® e ao EDTA, apresentando diferença estatisticamente significante ao EDTA no terço cervical. O uso do ultra-som não promoveu uma melhora significante na capacidade de limpeza de todas as soluções irrigadoras testadas. Em todos os grupos, o resultado menos favorável em relação à remoção da camada de smear layer foi observado no terço apical do canal radicular, com diferença estatisticamente significante em relação ao terço cervical. / The aim of this study was to evaluate the smear layer removal from instrumented root canal walls by saline solution, 17% EDTA, apple vinegar and SmearClear®, at three radicular levels, with or without ultrasonics. For that purpose, 70 upper and lower human canines were used, which had their crowns removed. The working length was established by visualizing the tip of a 10 K-type file at the apical foramen, by reducing 1 mm from this measurement. For preparation of root canal, the teeth were instrumented with rotatory files ProTaper®, using the crown-down technique, up to F5 instrument, irrigating with 2,5% sodium hypochlorite between each instrument change. The teeth were randomly divided into 6 groups of 10 teeth each and 2 control groups of 5 teeth according to the final irrigation protocol: Group 1 (control) Saline solution for 3 minutes without ultrasonics; Group 2 (control) Saline solution for 3 minutes, with ultrasonic activation for the first minute; Group 3 17% EDTA for 3 minutes without ultrasonics; Group 4 17% EDTA for 3 minutes, with ultrasonic activation for the first minute; Group 5 Apple vinegar for 3 minutes without ultrasonics; Group 6 Apple vinegar for 3 minutes, with ultrasonic activation for the first minute; Group 7 - SmearClear® for 1 minute without ultrasonics; Group 8 - SmearClear® for 1 minute with ultrasonic activation. Subsequently, the teeth were irrigated with 2,5% sodium hypochlorite and dried with paper points. The teeth were split open longitudinally and prepared for scanning electron microscopy at magnification of 750X. Photomicrographs were taken from coronal, middle and apical thirds and analyzed by three examiners for scores attribution for statistical analysis. It was concluded that EDTA and SmearClear® were efficient for smear layer removal from root canals, with a discrete superiority of EDTA, however, without statistical significance. The saline solution showed significant inferior results compared with the others solutions. Apple vinegar was slightly inferior to SmearClear® and EDTA, with statistical difference observed between apple vinegar and EDTA in coronal third. The ultrasonics did not enhance the cleaning ability of all the irrigating solutions tested. In all cases, the least favorable result regarding smear layer removal was observed in the apical third of the root canal, with statistically significant differences in the coronal third.
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Interactive Training System for Medical UltrasoundBanker, Christian John 17 February 2009 (has links)
Ultrasound is an effective imaging modality because it is safe, unobtrusive and portable. However, it is also very operator-dependent and significant skill is required to capture quality images and properly detect abnormalities. Training is an important part of ultrasound, but the limited availability of training courses presents a significant hindrance to the use of ultrasound being used in additional settings. The goal of this work was to design and implement an interactive training system to help train and evaluate sonographers. The Interactive Training System for Medical Ultrasound is an inexpensive, software-based training system in which the trainee scans a lifelike manikin with a sham transducer containing a 6 degree of freedom tracking sensor. The observed ultrasound image is generated from a pre-stored 3D image volume and is controlled interactively by the sham transducer's position and orientation. Based on the selected 3D volume, the manikin may represent normal anatomy, exhibit a specific trauma or present a given physical condition. The training system provides a realistic scanning experience by providing an interactive real-time display with adjustable image parameters such as scan depth, gain, and time gain compensation. A representative hardware interface has been developed including a lifelike manikin and convincing sham transducers, along with a touch screen user interface. Methods of capturing 3D ultrasound image volumes and stitching together multiple volumes have been evaluated. System performance was analyzed and an initial clinical evaluation was performed. This thesis presents a complete prototype training system with advanced simulation and learning assessment features. The ultrasound training system can provide cost-effective and convenient training of physicians and sonographers. This system is an innovative approach to training and is a powerful tool for training sonographers in recognizing a wide variety of medical conditions.
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An Injury-Mimicking Ultrasound Phantom as a Training Tool for Diagnosis of Internal TraumaRowan, Matthew Ivan 20 December 2006 (has links)
"Ultrasound phantoms that mimic injury are training devices that can emulate pre- and post-injury conditions within specific regions of human anatomy. They have the potential to be useful tools for teaching medical personnel how to recognize trauma conditions based on ultrasound images. This is particularly important because the increased use of portable ultrasound systems allows earlier diagnosis of internal trauma at locations such as traffic accidents, earthquakes, battlefields and terrorist attacks. A physical injury mimicking ultrasound phantom of the peritoneal cavity was constructed that mimicked the ultrasonic appearance of internal bleeding. Bleeding was simulated by injecting 600 mL of fluid of varying densities into the bulk of the phantom and comparing the ultrasonic appearance to before bleeding was simulated. The physical phantom was used to investigate whether or not the density of the injected fluid had any influence on the increase of inter-organ fluid volumes. The physical phantom was imaged in 3D with a 4.5 MHz phased array transducer, and two fluid volumes were segmented using the segmentation software ITK-SNAP. The 3D image representation of the phantom showed a difference qualitatively and quantitatively between pre-injury and post-injury conditions. Qualitatively, the physical model was analyzed. These specific criteria were analyzed within each image: 1) the number of individual organs that are present, 2) the number of other organs that each individual organ touches, 3) the appearance of fluid between the organs and the scanning membrane and 4) the merging of two separate fluid pockets. Using a Wilcoxon Rank-Sum test, a statistically significant difference was shown to exist between pre-injury and post-injury ultrasound images with a 95% level of confidence. Quantitatively, a Chi-Squared test was used to show that the volume of fluid between adjacent organs, calculated by ITK-SNAP, had no dependence on the density of the injected fluid. Furthermore, using a one-tailed T-test, there was at least a 99.9% confidence that the inter-organ volume estimations for the pre-injury and post-injury configurations were statistically different. As a final means of evaluation, the experimental phantom was taken to Harvard Medical School in November 2006 and analyzed by ultrasonographers. The doctors were very excited about its potential uses and found other interesting characteristics that the phantom was not designed for. In addition to modeling the appearance of an injected fluid volume, visualization of fluid flowing into the phantom, modeling the appearance of air in the inter-peritoneal space and simulating a surgical tool or bandage being accidentally left inside the patient could be modeled as well. The injury mimicking phantom was also modeled numerically, using ADINA finite element software. Using the same external dimensions as the experimental model, the numerical model showed that for physiologically unrealistic, very high fluid injection densities, the displacement of the organs had no statistical dependence on the density of the injected fluid, using an acceptance criterion of: P-value < 0.05. This was confirmed using an F-test of the average organ phantom tip displacement tabulated at several different times during simulation. The P-value obtained for analyzing the average tip displacement was 0.0506. However, a plot of the mass ratio, an expression of how the injected fluid has dispersed into the bulk of the phantom, showed that an unrealistically high fluid injection density had a different mass ratio profile than the other fluid injection densities that were simulated. This F-test revealed a strong indication, P-value = 0.0069, that the very high density caused a different fluid dispersion pattern. The numerical phantom offered a distinct advantage over the experimental model in that the dispersion of the injected fluid could be modeled numerically but not observed experimentally. Modeling the phantom numerically had some disadvantages. The numerical model had to have a large gap between adjacent organs. This had to occur because the contact algorithm within ADINA is incapable of modeling dynamic contact when fluid-structure interactions are modeled. This led to a volume fraction representation of the solid domain that was too low compared with the experimental model and what is found anatomically. For future iterations of the injury mimicking phantom, the numerical model will be used to help design the physical phantoms."
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An electronically steered ultrasonic transducer.Maslak, Samuel Harry January 1975 (has links)
Thesis. 1975. Sc.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / Vita. / Includes bibliographical references. / Sc.D.
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Avaliação dos parâmetros de imagens de massas anexiais pélvicas em tele-ecografia.Gonçalves, Fausto da Silva 14 March 2013 (has links)
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Previous issue date: 2013-03-14 / Introduction: According to the World Health Organization, is a diagnostic imaging procedure necessary for the accurate treatment of at least 25% of patients worldwide. While the imaging technology has evolved so dizzying, over 90% of all images required can be performed with simple machines to ultrasound and X- rays. There are data indicating Transvaginal Ultrasonography as one of the most effective methods for detecting ovarian tumors, to be safe, fast, easy to perform and well accepted by patients. It is the most frequently used test for this purpose due to its excellent cost / benefit ratio, being an innocuous and widely used method in the diagnosis of adnexal masses. Numerous studies have been conducted to differentiate adnexal masses and thereby reduce the number of patients subjected to inappropriate treatment. Objectives: Evaluation of sonographic parameters related with the morphological characteristics of pelvic adnexal masses by obtaining two-dimensional images taken by observer presence and sent electronically (via Tele-Ultrasound) in static mode and dynamic observers do not face (distance) for comparative analyzes inter-and intra-observer and validation of a second opinion. Methods: From March to August 2010 50 patients were selected for presenting viewing adnexal mass on ultrasound. The pelvic sonographic examinations were performed by cesarean section and by vaginal Imaging Unit in the Department of Obstetrics and Gynecology, Hospital de Base in São José do Rio Preto. The adnexal masses were evaluated according to their morphological characteristics. Results: There was good inter-rater agreement independent of the modality (dynamic and static) used. Conclusions: The sonographic parameters of the morphological characteristics of pelvic adnexal masses directed by Tele-Ultrasound is capable of being validated for issuing a second opinion. There were no significant differences in the methodology employed in the issue of tele-ultrasound images (static or dynamic) to characterize the composition of pelvic adnexal masses. / Introdução: De acordo com a Organização Mundial de Saúde, o diagnóstico por imagem é um procedimento necessário para o tratamento acurado de pelo menos 25% dos pacientes em todo o mundo. Embora a tecnologia de imagem tenha evoluído de forma vertiginosa, mais de 90% de todas as imagens
necessárias podem ser realizadas com máquinas simples de Ultrassonografia e Raios-X. Há dados indicando a Ultrassonografia Transvaginal como um dos métodos mais efetivos para detecção de tumores ovarianos, por ser seguro, rápido, fácil de realizar e bem aceito pelas pacientes. É o exame mais utilizado para esse propósito devido a sua excelente relação custo/benefício, ser um método inócuo e amplamente utilizado no diagnóstico de massas anexiais. Inúmeros estudos têm sido realizados para diferenciar as massas anexiais e assim reduzir o número de pacientes submetidas a tratamentos inadequados. Objetivos: Avaliação dos parâmetros ultrassonográficos relacionados com as
características morfológicas de massas anexiais pélvicas através da obtenção de imagens bidimensionais realizadas por observador presencial e encaminhadas eletronicamente (via Tele-Ecografia) no modo estático e dinâmico a observadores não presenciais (à distância) para análises comparativas inter e intra- observadores e validação de uma segunda opinião. Casuística e métodos: No período de março a agosto de 2010 foram selecionadas 50 pacientes por apresentarem visualização de massa anexial ao exame ecográfico. Os exames ultrassonográficos pélvicos foram realizados por via abdominal e por via endovaginal na Unidade de Imagenologia do Departamento de Ginecologia e Obstetrícia do Hospital de Base de São José do Rio Preto. As massas anexiais foram avaliadas de acordo com suas características morfológicas. Resultados: Houve uma boa concordância inter-examinadores independente da modalidade (dinâmica e estática) utilizada. Conclusões: Os parâmetros ultrassonográficos das características morfológicas de massas anexiais pélvicas encaminhadas por Tele-Ecografia são passíveis de serem validadas para a emissão de uma segunda opinião. Não houve diferenças significativas quanto à metodologia empregada na emissão das imagens tele-ecograficas (estática ou dinâmica) na caracterização da composição das massas anexiais pélvicas.
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Ultrassom portátil de bexiga: evidências científicas e autoconfiança do enfermeiro / Portable ultrasound bladder: scientific evidence and self confidence of nursesBeatriz Maria Jorge 29 January 2014 (has links)
A assistência de enfermagem na retenção urinária (RU) incorre na importância da avaliação clínica do enfermeiro. O ultrassom portátil de bexiga (US) é um método não-invasivo que permite diagnosticar o problema, avaliar o volume de urina na bexiga, e decidir ou não, pela realização do cateterismo urinário. Este estudo teve como objetivo avaliar o impacto do uso do ultrassom portátil de bexiga na autoconfiança do enfermeiro durante a avaliação do paciente em retenção urinária. Estudo realizado em duas etapas. Etapa 1- Revisão integrativa da literatura realizada nas bases de dados CINAHL, MEDLINE e Web of Science através dos descritores enfermagem, retenção urinária e ultrassom. Foram inclusas as publicações realizadas no período de 2001 a 2011, nos idiomas inglês, português e espanhol que responderam a pergunta da pesquisa. Etapa 2- Estudo descritivo, mediante autorização ética (Parecer P129-12/2012), desenvolvido junto aos enfermeiros de um Centro de Reabilitação de Portugal, com auxílio de Escala de Autoconfiança na Assistência de Enfermagem à Retenção Urinária (EAAERU). Trata-se de uma escala já validada, tipo Likert de 32 itens, agrupados em cinco fatores: medidas prévias a realização do cateterismo voltadas ao preparo do paciente e profissional; comunicação, consentimento e preparo do material para realização do cateterismo urinário; medidas realizadas durante a realização do cateterismo urinário e/ou em situações iatrogênicas; medidas realizadas após a realização e retirada do cateterismo; avaliação objetiva da RU. Foram encontrados os seguintes resultados: Etapa 1 - Dos 234 artigos encontrados, após leitura exaustiva dos títulos e resumos, foram selecionados 21 artigos. Entre eles, 21 (100,0%), todos foram publicados em inglês, 10 (47,6%) em periódicos de enfermagem, 10 (47,6%) em periódicos médicos e 1 (4,7%) em periódico interdisciplinar. Em relação aos níveis de evidência, 1 (4,7%) apresentou nível I, 1 (4,7%) nível II, 9 (42,8%) nível III, 1 (4,7%) nível IV e 9 (42,8%) nível VI. Quanto aos países de publicação: Canadá (19,0%), Estados Unidos da América (19,0%), Inglaterra (19,0%), Noruega (9,5%), Taiwan (9,5%), Itália (9,5%), Austrália (4,7%), Holanda (4,7%) e França (4,7%). O ano que apresentou maior número de publicações foi o de 2005 (28,5%). Todos os artigos demonstram a eficácia e a eficiência do uso do equipamento na avaliação do paciente em retenção urinária. Etapa 2 - Fizeram parte da amostra 40 enfermeiros; a maioria do sexo feminino (62,5%), com idade média de 35,3 anos, que obtiveram o título de Enfermagem entre 1978 e 2010. Entre eles 13 (32,5%) eram especialistas em reabilitação. A maior parte dos enfermeiros referiu que trabalha na profissão há cerca de 20 anos e 23 (57,5%) possuem menos de cinco anos de tempo de experiência no local de trabalho atual. Assim como na escala original para avaliação dos itens da escala foi utilizado o teste do Alpha de Cronbach que demonstrou uma elevada correlação (Valor de Alpha 0,969) de todos os itens da EAAERU. Quanto à análise de correspondência da autoconfiança dos enfermeiros em relação aos cinco fatores propostos pela escala os resultados demonstraram que os enfermeiros referem confiante, muito confiante e completamente confiante para medidas prévias a realização do cateterismo voltadas ao preparo do paciente e profissional; muito confiante e completamente confiante para comunicação, consentimento e preparo do material para realização do cateterismo urinário; muito confiante e completamente confiante para medidas realizadas durante a realização do cateterismo urinário e/ou em situações iatrogênicas; completamente confiante para medidas realizadas após a realização e retirada do cateterismo e pouco confiante e confiante para avaliação objetiva da RU. Conclui-se que o US é um método eficiente e confiável, que supera a investigação de sinais e sintomas clínicos. Permite o diagnóstico precoce, é um procedimento não invasivo, indolor, que utiliza a tecnologia de forma segura e avalia com precisão a necessidade ou não do cateterismo urinário, evitando a distensão excessiva da bexiga urinária e as complicações oriundas desse fato. Conforme os resultados da amostra é possível observar que mesmo com os predicados que o US possui, na assistência de enfermagem a retenção urinária, a avaliação do paciente em RU é o procedimento mais complexo e exerce influência negativa na autoconfiança do enfermeiro / Nursing care in urinary retention (RU) incurs the importance of clinical evaluation of the nurse. The portable bladder ultrasound (US) is a noninvasive method that allows you to diagnose the problem, assess the volume of urine in the bladder and decide whether or not for performing urinary catheterization. This study aimed to evaluate the impact of the use of portable ultrasound bladder for the nurse\'s confidence during patient evaluation in urinary retention. This study was conducted in two stages: Step 1 - Integrative literature review conducted in CINAHL, MEDLINE and Web of Science databases using descriptors of nursing, ultrasound and urinary retention. Publications in the period 2001-2011 in English, Portuguese and Spanish which answered the survey questions. Step 2 - Descriptive study by ethical commitment (Opinion P129- 12/2012), developed together with nurses in a rehabilitation center of Portugal with the aid of Self-Confidence Scale in Nursing Assistance Urinary Retention (EAAERU). This is a validated scale, Likert 32 items, grouped into five factors: previous steps of the catheterization realization focused on patient and professional\'s preparation; communication, consent and preparation of the material for performing urinary catheterization; steps performed during urinary catheterization performing and/or iatrogenic situations; steps taken after the completion of the catheterization and withdrawal; objective evaluation of UR. Were found the following results: Step 1 - Of the 234 articles found, after carefully reading the titles and abstracts, 21 articles were selected. Among them, 21 (100,0%) , were all published in English , 10 ( 47,6 % ) in nursing journals, 10 (47,6%) in medical journals and 1 (4,7%) in interdisciplinary journal. Regarding the levels of evidence , 1 (4,7%) presented level I, 1 (4,7%) level II, 9 (42,8%) level III, 1 (4,7%) level IV and 9 (42,8%) level VI. The countries of publication: Canada (19,0%), United States of America (19,0%), England (19,0%), Norway (9,5%), Taiwan (9,5%), Italy (9,5%), Australia (4,7%), Netherlands (4,7%) and France (4,7%). The year that had the highest number of publications was 2005 (28,5%). All articles demonstrate the effectiveness and efficiency of the use of equipment to assess patients in urinary retention. Step 2 - The sample consisted of 40 nurses, the majority of females (62,5%) with mean age of 35,3 years, who obtained the title of Nursing between 1978 to 2010. Among them, 13 (32,5%) were specialists in rehabilitation. Most nurses reported working in the profession for about 20 years and 23 (57,5%) have less than five years of experience time in the current workplace. As in the original scale for assessment of the scale items the Cronbach\'s Alpha test which showed a high correlation (0,969 Alpha value) of all items SSNAUR. As for the correspondence analysis of the self-confidence of nurses in relation to the five factors proposed by the scale results showed that nurses refer confident, very confident and totally confident to previous steps of the catheterization realization focused on patient and professional\'s preparation; very confident and completely confident to communication, consent and preparation of the material for performing urinary catheterization; very confident and completely confident to steps performed during urinary catheterization performing and/or iatrogenic situations; completely confident to steps taken after the completion of the catheterization and withdrawal; and little confident and confident for objective evaluation of UR. It is concluded that the US is an efficient and reliable method, which overcomes the investigation of clinical signs and symptoms. Allows early diagnosis, is a painless, non-invasive procedure that uses technology in a safe way and assess accurately the need or not urinary catheterization, avoiding excessive distension of the urinary bladder and the complications arising from that fact. As the sample results can be observed that, even with the predicates that the US has, in nursing care for urinary retention, patient assessment in the UR is the most complex procedure and exerts negative influence on the confidence of nurses
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A study of the enhancement effects of low-intensity pulsed ultrasound on fracture healing at different angles of applications with a rat model.January 2008 (has links)
Chung, Shu Lu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 109-118). / Abstracts in English and Chinese. / Abstract --- p.i-iv / 中文摘要 --- p.v-vii / Publications --- p.viii / Acknowledgements --- p.ix / List of Abbreviations --- p.x-xi / Index for Figures --- p.xii-xiv / Index for Tables --- p.xv / Table of Contents --- p.xvi-xix / Chapter Session 1: --- Introduction --- p.1 / Chapter 1.1 --- Biology of fracture healing process --- p.2 / Chapter 1.1.1 --- Stage of inflammation --- p.2-3 / Chapter 1.1.2 --- Stage of soft callus formation --- p.3-4 / Chapter 1.1.3 --- Stage of hard callus formation --- p.4-5 / Chapter 1.1.4 --- Stage of bone remodeling --- p.5 / Chapter 1.2 --- Conventional treatments and its limitations --- p.5-6 / Chapter 1.3 --- Biological treatments in accelerating fracture healing process --- p.6-7 / Chapter 1.4 --- Biophysical treatments in accelerating fracture healing process --- p.7-8 / Chapter 1.4.1 --- Electromagnetic fields --- p.8-9 / Chapter 1.4.2 --- Shockwave --- p.9 / Chapter 1.4.3 --- Low intensity pulsed ultrasound --- p.9-11 / Chapter 1.5 --- Properties of ultrasound --- p.11 / Chapter 1.5.1 --- Ultrasound signals --- p.11-12 / Chapter 1.5.2 --- Attenuation of ultrasound --- p.12-14 / Chapter 1.5.3 --- Modes of ultrasound wave propagation --- p.14-15 / Chapter 1.5.4 --- Reflection and critical angle --- p.15-18 / Chapter 1.6 --- Insights from previous studies --- p.18-19 / Chapter 1.7 --- Hypothesis --- p.19 / Chapter 1.8 --- Study plan --- p.20 / Chapter 1.9 --- Objectives --- p.20 / Chapter Session 2: --- Materials and Methodology --- p.25 / Chapter 2.1 --- Materials --- p.26 / Chapter 2.2. --- Closed femoral fracture rat model --- p.26 / Chapter 2.2.1 --- Operation procedures --- p.26-27 / Chapter 2.3 --- Groupings --- p.27 / Chapter 2.4 --- Low Iintensity Pulsed Ultrasound treatment --- p.28 / Chapter 2.4.1 --- Incident angles determination --- p.28 / Chapter 2.4.2 --- LIPUS devices --- p.29 / Chapter 2.4.2 --- Set up of standardized platform --- p.29-30 / Chapter 2.4.4 --- Treatment procedure --- p.30 / Chapter 2.5 --- Radiographic analysis --- p.31 / Chapter 2.6 --- Micro-Computed Tomography --- p.32 / Chapter 2.6.1 --- Micro-Computed Tomography scanning --- p.32 / Chapter 2.6.2 --- Micro-Computed Tomography analysis --- p.32-33 / Chapter 2.7 --- Histology --- p.34 / Chapter 2.7.1 --- Sample preparation --- p.34 / Chapter 2.7.2 --- Histomorphometrical analysis --- p.34-35 / Chapter 2.8 --- Mechanical Testing --- p.35 / Chapter 2.9 --- Statistical analysis --- p.35 / Chapter Session 3: --- Results --- p.48 / Chapter 3.1 --- Radiographic analysis --- p.49 / Chapter 3.1.1 --- Qualitative analysis - Callus bridging rate --- p.49 / Chapter 3.1.2 --- Quantitative analysis - Callus area and callus width --- p.49-50 / Chapter 3.2 --- Micro-computed tomography analysis --- p.50 / Chapter 3.2.1 --- Qualitative analysis - 3D reconstructed images --- p.50-51 / Chapter 3.2.2 --- Quantitative analysis - Bone volume of callus --- p.51 / Chapter 3.2.3 --- Quantitative analysis - Bone mineral density and bone mineral content --- p.51-52 / Chapter 3.3 --- Biomechanical test --- p.52-53 / Chapter 3.4 --- Histomorphological analysis --- p.53 / Chapter 3.4.1 --- Qualitative analysis --- p.53 / Chapter 3.4.2 --- Quantitative analysis --- p.53-54 / Chapter Session 4: --- Discussion --- p.85-87 / Chapter 4.1 --- Enhancement effects of LIPUS at different incident angles --- p.88 / Chapter 4.1.1 --- LIPUS transmitted at 350 accelerated the fracture healing process --- p.88 / Chapter 4.1.1.1 --- Callus bridging and callus mineralization --- p.88-89 / Chapter 4.1.1.2 --- Dose dependent effects of LIPUS -Maximization of ultrasound energy --- p.89-90 / Chapter 4.1.2 --- LIPUS transmitted at 35° enhanced the restoration of mechanical properties in fracture healing process --- p.90 / Chapter 4.1.2.1 --- Biomechanical properties --- p.90-91 / Chapter 4.1.2.2 --- Bone mineral density and bone mineral content --- p.91-92 / Chapter 4.1.2.3 --- Highly mineralized callus area and volume --- p.92-93 / Chapter 4.2 --- 35° may be the critical angle for further enhancing fracture healing --- p.93 / Chapter 4.2.1 --- LIPUS transmitted at 35° may be the first critical angle in this study --- p.93-95 / Chapter 4.2.2 --- Effects of different incident angles --- p.95-96 / Chapter 4.3 --- Mechanism of LIPUS at different incident angles on fracture healing process --- p.96 / Chapter 4.3.1 --- Endochondral ossification --- p.96-99 / Chapter 4.4 --- Advantages in using LIPUS transmitted at critical angle --- p.99 / Chapter 4.5 --- Limitations of the study --- p.100 / Chapter 4.5.1 --- Animal model --- p.100 / Chapter 4.5.2 --- Treatment sites of LIPUS transmitted at different incident angles --- p.100 / Chapter 4.5.3 --- Types of fracture --- p.101 / Chapter Session 5: --- Conclusions --- p.102-104 / Chapter Session 6: --- Future Studies --- p.105 / Chapter 6.1 --- Protocol and regime of LIPUS transmitted at different angles --- p.106 / Chapter 6.2 --- Periosteum-stripped fracture model --- p.106-107 / Chapter 6.3 --- Molecular mechanism of LIPUS transmitted at different incident angles --- p.107-108 / Bibliography --- p.109-118 / Appendix I --- p.119
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Maximum Entropy Regularisation Applied to Ultrasonic Image ReconstructionBattle, David John January 1999 (has links)
Image reconstruction, in common with many other inverse problems, is often mathematically ill-posed in the sense that solutions are neither stable nor unique. Ultrasonic image reconstruction is particularly notorious in this regard, with narrow transducer bandwidths and limited - sometimes sparsely sampled apertures posing formidable difficulties for conventional signal processing. To overcome these difficulties, some form of regularisation is mandatory, whereby the ill-posed problem is restated as a closely related, well-posed problem, and then solved uniquely. This thesis explores the application of maximum entropy (MaxEnt) regularisation to the problem of reconstructing complex-valued imagery from sparsely sampled coherent ultrasonic field data, with particular emphasis on three-dimensional problems in the non-destructive evaluation (NDE) of materials. MaxEnt has not previously been applied to this class of problem, and yet in comparison with many other approaches to image reconstruction, it emerges as the clear leader in terms of resolution and overall image quality. To account for this performance, it is argued that the default image model used with MaxEnt is particularly meaningful in cases of ultrasonic scattering by objects embedded in homogeneous media. To establish physical and mathematical insights into the forward problem, linear equations describing scattering from both penetrable and impenetrable objects are first derived using the Born and physical optics approximations respectively. These equations are then expressed as a shift-invariant computational model that explicitly incorporates sparse sampling. To validate this model, time-domain scattering responses are computed and compared with analytical solutions for a simple canonical test case drawn from the field of NDE. The responses computed via the numerical model are shown to accurately reproduce the analytical responses. To solve inverse scattering problems via MaxEnt, the robust Cambridge algorithm is generalised to the complex domain and extended to handle broadband (multiple-frequency) data. Two versions of the augmented algorithm are then compared with a range of other algorithms, including several linearly regularised algorithms and lastly, due to its acknowledged status as a competitor with MaxEnt in radio-astronomy, the non-linear CLEAN algorithm. These comparisons are made through simulated 3-D imaging experiments under conditions of both complete and sparse aperture sampling with low and high levels of additive Gaussian noise. As required in any investigation of inverse problems, the experimental confirmation of algorithmic performance is emphasised, and two common imaging geometries relevant to NDE are selected for this purpose. In monostatic synthetic aperture imaging experiments involving side-drilled holes in an aluminium plate and test objects immersed in H2O, MaxEnt image reconstruction is demonstrated to be robust against grating-lobe and side-lobe formation, in addition to temporal bandwidth restriction. This enables efficient reconstruction of 2-D and 3-D images from small numbers of discrete samples in the spatial and frequency domains. The thesis concludes with a description of the design and testing of a novel polyvinylidene fluoride (PVDF) bistatic array transducer that offers advantages over conventional point-sampled arrays in terms of construction simplicity and signal-to-noise ratio. This ultra-sparse orthogonal array is the only one of its kind yet demonstrated, and was made possible by MaxEnt signal processing.
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Acceptance Criteria for Ultrasonic Impact Treatment of Highway Steel BridgesTehrani Yekta, Rana January 2012 (has links)
The need for rehabilitation of bridges has become a critical challenge due to aging and an increase in traffic loads. Many of these bridges are exceeding their design fatigue life. Since many of these bridges are structurally deficient, they need to be rehabilitated or replaced by a new bridge. The most susceptible and weak parts of steel bridges to cracks and fatigue are the welds, due to the presence of high stress concentrations, tensile residual stresses, and imperfections as a result of the welding process. Inspection and repair of welds are difficult and elimination of welded details is not possible in steel bridge construction. Ultrasonic impact treatment (UIT) is a promising and innovative post-weld treatment (PWT) method for improving the fatigue performance of existing welded steel and steel-concrete composite structures such as highway bridges. The fatigue resistance of treated joints is enhanced by improving the geometry of the weld toe, and introducing compressive residual stresses. However, a lack of tools for quality assurance has slowed UIT’s adoption by bridge authorities.
The current study was undertaken to examine the fatigue performance of structural steel welds subjected to UIT at various levels, including intentional under-treatment and over-treatment, and to relate the fatigue performance of the treated welds to geometric and metallurgical properties measured to control the treatment quality. The last objective was to use the laboratory results to develop acceptance criteria for the quality control of UIT in bridge applications.
Fatigue tests of non-load carrying fillet welded attachments were conducted on properly treated, under-treated, and over-treated weld toes. Statistical analyses of the fatigue life data were performed and crack growth was monitored using the alternating current potential drop (ACPD) method. Measurement of local properties (such as weld toe geometry, local hardness, and residual stresses) and examination of the weld toe microstructure were also performed on the untreated and treated welds. The effects of weld toe geometry on the local stresses in the untreated and treated welds were also investigated using elastic finite element analysis (FEA) to obtain the stress concentration factor (SCF) for the different treatment cases and to examine the changes in the SCF for the different weld toe geometries.
Based on the statistical analysis performed in this research, the results illustrated that UIT significantly improved the fatigue lives of weld details regardless of the investigated level of treatment quality. The fatigue lives of welded details under constant amplitude (CA) loading and constant amplitude loading with under-loads (CA-UL) were increased up to 30 and 27 times respectively. On average, the fatigue life of the treated weld details was slightly lower under CA-UL than under CA loading. Treatment quality had little impact on the mean of the S-N curves. However, it did impact the design (95% survival probability) S-N curves, with the curve associated with a proper treatment slightly higher than the curves for poor or unknown treatment quality. Local near-surface microhardness and compressive residual stresses were greatest for the over-treated welded details, followed by the properly treated and then the under-treated welded details. Increasing the treatment speed resulted in a greater reduction in the surface microhardness and compressive residual stresses than decreasing the treatment intensity.
Finite element analyses showed that changes in weld toe geometry due to UIT can cause a decrease in the SCF near the surface of the treated weld toe. The SCF was the lowest for the properly treated steel specimens and slightly higher for the under-treated specimens. For the over-treated specimens, the SCFs were nearly as high as for the untreated weld. The SCF increases as the thickness of the flange increased up to 19 mm. With further flange thickness increase to 38 mm, the SCF did not change substantially.
The work presented herein demonstrated that indent depth measurements from the base metal side, commonly used for quality control, may not identify over-treatment on their own. Indent depth measurements from both the weld and the base metal sides, obtained by measurement of weld toe impressions, offer a good alternative means for identifying over-treatment. However, for identifying under-treatment, indent depth measurements should be used in conjunction with visual inspection for traces of the original weld toe.
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