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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Radiographic contrast-enhancement masks in digital radiography

Davidson, Robert Andrew January 2006 (has links)
Doctor of Philosophy / Radiographic film/screen (F/S) images have a narrow latitude or dynamic range. The film’s ability to record and view all the anatomy within the x-ray field is limited by this narrow dynamic range. The advent of digital radiographic means of storing and displaying radiographic images has improved the ability to record and visualise all of the anatomy. The problem still exists in digital radiography (DR) when radiographic examinations of certain anatomical regions are undertaken. In this work, the value of anatomically shaped radiographic contrast-enhancement masks (RCMs) in improving image contrast and reducing the dynamic range of images in DR was examined. Radiographic contrast-enhancement masks are digital masks that alter the radiographic contrast in DR images. The shape of these masks can be altered by the user. Anatomically shaped RCMs have been modelled on tissue compensation filters (TCFs) commonly used in F/S radiographic examinations. The prime purpose of a TCF is to reduce the dynamic range of photons reaching the image receptor and hence improve radiographic contrast in the resultant image. RCMs affect the dynamic range of the image rather than the energy source of the image, that of the x-ray photons. The research consisted of three distinct phases. The first phase was to examine physical TCFs and their effects on F/S radiographic images. Physical TCFs are used in radiographic F/S examinations to attenuate the x-ray beam to compensate for varying patient tissue thicknesses and/or densities. The effect of the TCF is to reduce resultant radiographic optical density variations in the image, allowing the viewer to observe a range of densities within the image which would otherwise not be visualised. Physical TCFs are commonly aluminium- or lead-based materials that attenuate the x-ray beam. A TCF has varying physical thickness to differentially attenuate the iii beam and is shaped for specific anatomical situations. During this project, various commonly used physical TCFs were examined. Measurements of size and thickness were made. Characteristics of linear attenuation coefficients and half-value thicknesses were delineated for various TCF materials and at various energies. The second phase of the research was to model the physical TCFs in a digital environment and apply the RCMs to DR images. The digital RCMs were created with similar characteristics to mimic the shapes to the physical TCFs. The RCM characteristics can be adjusted by the viewer of the image to suit the anatomy being imaged. Anatomically shaped RCMs were designed to assist in overcoming a limitation when viewing digital radiographic images, that of the dynamic range of the image. Anatomically shaped RCMs differ from other means of controlling the dynamic range of a digital radiographic image. It has been shown that RCMs can reduce the range of optical densities within images with a large dynamic range, to facilitate visualisation of all anatomy within the image. Physical TCFs are used within a specific range of radiographic F/S examinations. Digital radiographic images from this range of examinations were collected from various clinical radiological centres. Anatomically shaped RCMs were applied to the images to improve radiographic contrast of the images. The third phase of the research was to ascertain the benefits of the use of RCMs. Various other methods are currently in use to reduce the dynamic range of digital radiographic images. It is generally accepted that these methods also introduce noise into the image and hence reduce image quality. Quantitative comparisons of noise within the image were undertaken. The anatomically shaped RCMs introduced less noise than current methods designed to reduce the dynamic range of digital radiographic images. It was shown that RCM methods do not affect image quality. Radiographers make subjective assessment of digital radiographic image quality as part of their professional practice. To assess the subjective quality of images enhanced with anatomically shaped RCMs, a survey of radiographers and other iv qualified people was undertaken to ascertain any improvement in RCM-modified images compared to the original images. Participants were provided with eight pairs of image to compare. Questions were asked in the survey as to which image had the better range of optical densities; in which image the anatomy was easiest to visualise; which image had the simplest contrast and density manipulation for optimal visualisation; and which image had the overall highest image quality. Responses from 123 participants were received and analysed. The statistical analysis showed a higher preference by radiographers for the digital radiographic images in which the RCMs had been applied. Comparisons were made between anatomical regions and between patient-related factors of size, age and whether pathology was present in the image or not. The conclusion was drawn that digital RCMs correctly applied to digital radiographic images decrease the dynamic range of the image, allowing the entire anatomy to be visualised in one image. Radiographic contrast in the image can be maximised whilst maintaining image quality. Using RCMs in some digital radiographic examinations, radiographers will be able to present optimised images to referring clinicians. It is envisaged that correctly applied RCMs in certain radiographic examinations will enhance radiographic image quality and possibly lead to improved diagnosis from these images.
102

Radiographic contrast-enhancement masks in digital radiography

Davidson, Robert Andrew January 2006 (has links)
Doctor of Philosophy / Radiographic film/screen (F/S) images have a narrow latitude or dynamic range. The film’s ability to record and view all the anatomy within the x-ray field is limited by this narrow dynamic range. The advent of digital radiographic means of storing and displaying radiographic images has improved the ability to record and visualise all of the anatomy. The problem still exists in digital radiography (DR) when radiographic examinations of certain anatomical regions are undertaken. In this work, the value of anatomically shaped radiographic contrast-enhancement masks (RCMs) in improving image contrast and reducing the dynamic range of images in DR was examined. Radiographic contrast-enhancement masks are digital masks that alter the radiographic contrast in DR images. The shape of these masks can be altered by the user. Anatomically shaped RCMs have been modelled on tissue compensation filters (TCFs) commonly used in F/S radiographic examinations. The prime purpose of a TCF is to reduce the dynamic range of photons reaching the image receptor and hence improve radiographic contrast in the resultant image. RCMs affect the dynamic range of the image rather than the energy source of the image, that of the x-ray photons. The research consisted of three distinct phases. The first phase was to examine physical TCFs and their effects on F/S radiographic images. Physical TCFs are used in radiographic F/S examinations to attenuate the x-ray beam to compensate for varying patient tissue thicknesses and/or densities. The effect of the TCF is to reduce resultant radiographic optical density variations in the image, allowing the viewer to observe a range of densities within the image which would otherwise not be visualised. Physical TCFs are commonly aluminium- or lead-based materials that attenuate the x-ray beam. A TCF has varying physical thickness to differentially attenuate the iii beam and is shaped for specific anatomical situations. During this project, various commonly used physical TCFs were examined. Measurements of size and thickness were made. Characteristics of linear attenuation coefficients and half-value thicknesses were delineated for various TCF materials and at various energies. The second phase of the research was to model the physical TCFs in a digital environment and apply the RCMs to DR images. The digital RCMs were created with similar characteristics to mimic the shapes to the physical TCFs. The RCM characteristics can be adjusted by the viewer of the image to suit the anatomy being imaged. Anatomically shaped RCMs were designed to assist in overcoming a limitation when viewing digital radiographic images, that of the dynamic range of the image. Anatomically shaped RCMs differ from other means of controlling the dynamic range of a digital radiographic image. It has been shown that RCMs can reduce the range of optical densities within images with a large dynamic range, to facilitate visualisation of all anatomy within the image. Physical TCFs are used within a specific range of radiographic F/S examinations. Digital radiographic images from this range of examinations were collected from various clinical radiological centres. Anatomically shaped RCMs were applied to the images to improve radiographic contrast of the images. The third phase of the research was to ascertain the benefits of the use of RCMs. Various other methods are currently in use to reduce the dynamic range of digital radiographic images. It is generally accepted that these methods also introduce noise into the image and hence reduce image quality. Quantitative comparisons of noise within the image were undertaken. The anatomically shaped RCMs introduced less noise than current methods designed to reduce the dynamic range of digital radiographic images. It was shown that RCM methods do not affect image quality. Radiographers make subjective assessment of digital radiographic image quality as part of their professional practice. To assess the subjective quality of images enhanced with anatomically shaped RCMs, a survey of radiographers and other iv qualified people was undertaken to ascertain any improvement in RCM-modified images compared to the original images. Participants were provided with eight pairs of image to compare. Questions were asked in the survey as to which image had the better range of optical densities; in which image the anatomy was easiest to visualise; which image had the simplest contrast and density manipulation for optimal visualisation; and which image had the overall highest image quality. Responses from 123 participants were received and analysed. The statistical analysis showed a higher preference by radiographers for the digital radiographic images in which the RCMs had been applied. Comparisons were made between anatomical regions and between patient-related factors of size, age and whether pathology was present in the image or not. The conclusion was drawn that digital RCMs correctly applied to digital radiographic images decrease the dynamic range of the image, allowing the entire anatomy to be visualised in one image. Radiographic contrast in the image can be maximised whilst maintaining image quality. Using RCMs in some digital radiographic examinations, radiographers will be able to present optimised images to referring clinicians. It is envisaged that correctly applied RCMs in certain radiographic examinations will enhance radiographic image quality and possibly lead to improved diagnosis from these images.
103

Design of photomodifiable material systems for maskless patterning of functional ceramic and metallic materials at multiple length scales

Alabi, Taiwo Raphael 29 March 2013 (has links)
Silicon and silicon-based materials have been investigated for the fabrication of electronic, optoelectronic, solar, and structural/mechanical devices. To enable the continuous use of silicon-based materials for next generation device applications, new and inexpensive ways of fabricating features of silicon, and silica-based materials are needed. This dissertation investigates: 1) novel techniques for the fabrication of silica and silicon nanofeatures with potential application in the electronics and optoelectronics industry; 2) new designs of photomodifiable material systems (resists) for maskless patterning of silica filled composites for structural/mechanical applications. Sub-micron and nano-scaled features were fabricated onto silicon and silicon oxide substrates using a technique combining block copolymers and laser interference ablation. The sacrificial block copolymers are loaded with metallic salt precursors and patterned with a UV laser to generate device-oriented nanofeatures. New photopolymerizable material systems (negative tone resists) were developed based on curcumin photosensitizer and an epoxy-acrylate, vinylether, and vinylether-acrylate silica¬-loaded material systems. The cationic and radical mechanisms employed by the monomeric systems under a high vapor pressure mercury lamp source were investigated with several materials characterization techniques.
104

Playing with masks : an exploration of craft and performance

Kurz, Danielle Haskell 23 October 2014 (has links)
Collaboration between the playwright, director, designer and technicians is the backbone of theater. Costume designers, after discussion with the director and the other designers, rely on costume technicians to realize their ideas. The technician’s hands then realize the artistic vision. But what would the technicians try if there were no constraints? I am a technician, a craftsperson who is inspired not just by the play, but also by process, by methods. With every new technique I learn, I imagine the new ways it could be put to use, and the objects I would create if time and resources were not a factor. Imagined objects are seldom created. Once made, these objects exist without a performance, without a purpose. A costume not worn is an unfulfilled destiny. But maybe the pieces I want to make can be given a narrative after the act of construction, or during construction. I’m interested in exploring my ability to be a generative artist. How can my inspiration feed back into the theater community? Can a costume technician’s experimentation have a place in creating new theater? My thesis has two components, exploring my two interests. Those two interests are the creation of objects and the creation of a story. The first component, object creation, was an exploratory study of mask and headdress making techniques. I experimented with new techniques, such as 3-D printing, testing the limitations of new technology. The second component, story creation, was a collaborative process. My collaborator, Brian Oglesby, and I worked concurrently. Brian is a playwright, and as he wrote the play, I made the objects. Our processes mirrored each other. The narrative of the play incorporated the masks and headpieces I made. This project created a theater piece based on the experimentation of a costume technician, and presents a new way for future technicians to think about their work and to have their stories told. / text
105

La Main ou le théâtre de l'identité trafiquée chez Michel Tremblay

Sareault, Guillaume 12 1900 (has links)
Ce mémoire veut, de prime abord, porter un regard sur la rue Saint-Laurent qui, depuis ses débuts, joue un rôle fondamental dans le tissu montréalais. Grâce à son visage bigarré et à son hétérogénéité, elle a su marquer l’histoire de la métropole et alimenter l’imaginaire d’un bon nombre d’écrivains. Michel Tremblay demeure un de ceux qui, dans l’ensemble de son oeuvre, explore le plus abondamment les clairs-obscurs et l’étrangeté de ce corridor urbain. Son écriture à la fois crue, marginale et théâtrale, s’inscrit pertinemment dans l’univers de la Main et, plus particulièrement, dans la partie du Redlight où aboutissent et se meuvent ses personnages les plus colorés. Ayant délaissé leur milieu d’origine, ces derniers s’imposent des changements radicaux afin de mieux cadrer avec la nature et les activités de leur terre d’accueil. Ce mémoire visera donc à penser l’« identité trafiquée » des personnages de Tremblay comme condition de leur inscription sur la rue Saint-Laurent. En outre, il sera question de l’esprit théâtral de cette artère qui pousse les travestis et les artistes en tout genre à se donner « en représentation » et à incarner un rôle de composition. Par l’entremise des masques – notamment celui du déguisement, du maquillage et du travestissement, mais aussi celui de la langue qu’ils modulent afin de mieux coller à leur personnage –, ils projettent une identité individuelle instable qui dévoile l’ambiguïté qui les habite. Plus largement, la présente étude s’intéressera à l’ensemble des marginaux qui arpentent la Main et qui cherchent à (re)définir leur identité culturelle, au milieu des cultures américaine et française. Bien qu’elle essaie de se forger une identité propre, cette collectivité peine à se définir sans calquer les modèles dont elle tente de se dissocier. Une telle contradiction évoque à bien des égards le paradoxe auquel se sont heurtées les communautés immigrantes de la rue Saint-Laurent, dont la lente adaptation à la culture nord-américaine s’est faite non sans un difficile constat de pertes et de gains face à la culture d’origine. Il s’agira donc de voir comment ces groupes, en apparence irréconciliables, trouvent dans le même univers un contexte favorable pour mener leur quête identitaire. / The primary objective of this thesis is to examine St. Laurent Street, which has played, since its early stages, a fundamental role in the city of Montreal. Due to its motley face and its heterogeneousness, this street marked the history of the metropolis and fed the imagination of many writers. Michel Tremblay is one who, within his work, explores most abundantly the twilight and the oddness of this urban corridor. His writing, which is considered controversial, raw and theatrical, pertinently frameworks the universe of The Main and, more specifically, the world of the Redlight District where his most colourful characters find themselves. Having left their place of origin, the characters bring about radical changes in order to fit in with the nature and the activities of their new neighborhood. This thesis will therefore aim to think out the « trafficked identity » (identité trafiquée) of Tremblay’s characters as the condition of their belonging on St. Laurent Street. Moreover, it will take a keen interest in the theatrical spirit of this main road, which influences transvestites and artists of all kinds to play a role and embody a made-up persona. Through the use of masks – notably disguises, make-up and cross-dressing, as well as language which they modulate in order to fit with their character –, they project an unstable identity that unveils the ambiguity that lies in them. The present study will also focus on the marginalized individuals who pace The Main as a group of people who look forward to (re)defining their cultural identity, due to the feeling of being stuck between the American and French culture. Although this community tries to build up its own identity, it struggles to define itself without imitating the models from which it attempts to dissociate itself. Such a contradiction evokes the paradox that faced immigrant communities on St. Laurent Street, whose slow adaptation to North-American culture took place with many gains and losses of their culture of origin. It will therefore be interesting to examine how these apparently irreconcilable groups find in the same universe a favorable context to lead their quest for identity.
106

Filtration des nanoparticules : application aux appareils de protection respiratoire / Filtration of nanoparticles : Application to Respiratory Protecting Devices

Brochot, Clothilde 11 May 2012 (has links)
Cette étude a pour objectif de déterminer dans quelle mesure les APR, dont les performances sont qualifiées pour des particules supérieures à 100 nm, sont efficaces pour des nanoparticules. En effet, dans le cas où l'utilisation d'une filtration collective est insuffisante, le port d'un Appareil de Protection Respiratoire (APR) est le dernier rempart préconisé. Une synthèse bibliographique a montré qu'aucune recherche n'a porté sur l'efficacité de demi-masques avec filtres pour des nanoparticules. Le banc d'ETude des NAnoparticules a été dimensionné et réalisé afin de pallier ces manques. Deux demi-masques ont été testés selon différentes configurations d'essais : débit constant et débit cyclique (débit moyen de 84 L/min) ; taille des particules (de 5 à 100 nm) ; pose du masque (scellée, libre, ou avec des fuites calibrées). Les résultats montrent que, dès lors que les APR utilisés contiennent des media (non électrets) efficaces pour des particules de la zone MPPS (100 nm - 300 nm), les APR sont plus efficaces pour les particules nanométriques. De plus, les résultats obtenus, en présence de fuites réelles et calibrées, ont mis en évidence l'importance des fuites au visage dans la détermination des performances des APR. Un modèle de calcul du facteur de protection a été établi, basé sur la différenciation des débits d'air traversant la fuite et le filtre. Cette modélisation a été validée à l'aide des mesures obtenues en présence des fuites calibrées, et appliquée pour l'analyse de nos résultats en pose libre / This study aims to determine how the respiratory protective devices (RPD), whose performances are qualified for particles above 100 nm, are effective for nanoparticles. Indeed, if the use of a collective filtration is inadequate, wearing a RPD is the last protection recommended. A literature review showed that no research concerned the effectiveness of half-masks for nanoparticles. The test bench ETNA has been sized and built to overcome these lacks. Two half masks were tested according to different configurations: constant flow rate and cyclic flow rate (average flow of 84 L /min) ; particle size (from 5 to 100 nm) ; positions of the mask (sealed, usual, or with calibrated leaks). The results show that, since the RPD contain high efficiency filter media (without charged fibers) for the most penetrating particle size (100 nm - 300 nm), the RPD is more efficient for nanoparticles. Furthermore, the results obtained in the presence of actual and calibrated leaks, highlighted the importance of faceseal leakages in determining the performance of RPD. A model for calculating the protection factor was established based on the balance between the airflow through the filter and the leak. This model was validated using measurements obtained in the presence of calibrated leaks, and applied for the analysis of our results in usual position
107

Avaliação da eficácia da máscara oronasal vs nasal com uso de pressão positiva para o tratamento da apneia obstrutiva do sono / Evaluation of the effectiveness of oronasal vs nasal mask with use of positive pressure for the obstructive sleep apnea treatment

Weaver, Fernanda Madeiro Leite Viana 22 March 2019 (has links)
Introdução: A aplicação de Pressão Positiva Contínua na Via Aérea Superior (CPAP) durante o sono é o tratamento padrão ouro para Apneia Obstrutiva do Sono (AOS) e foi primeiramente descrita utilizando uma máscara nasal. No entanto, na prática clínica a máscara oronasal é comumente utilizada e sua eficácia é variável devido a mecanismos desconhecidos. Nós formulamos a hipótese de que a respiração oral e a transmissão de pressão pela cavidade oral comprometem a eficácia do CPAP com máscara oronasal. Métodos: Treze pacientes com AOS, bem adaptados à máscara oronasal, foram monitorados com polissonografia completa, cateter de pressão faríngea e nasoendoscopia. Os pacientes dormiram com uma máscara oronasal com compartimentos nasal e oral separados e selados entre si. Cada compartimento nasal e oral foi conectado a um pneumotacógrafo e ambos foram conectados a uma válvula multidirecional a fim de ser possível modificar o fluxo de CPAP (nasal ou oronasal), sem a necessidade de acordar o paciente. Um cateter de pressão faríngea e broncoscópio pediátrico ultra-fino foram introduzidos por orifícios independentes através da máscara. O sono foi induzido com baixas doses de midazolam. O CPAP foi titulado até a pressão terapêutica durante as rotas oronasal e nasal. O CPAP foi então reduzido para induzir limitação de fluxo aéreo estável na rota oronasal e abruptamente mudado para a rota nasal e vice-versa. Adicionalmente, o experimento foi repetido com o uso de uma fita selando a boca do paciente a fim de bloquear a transmissão de pressão pela cavidade oral. Resultados: A pressão de titulação de CPAP foi maior na rota oronasal quando comparada à nasal (p=0,005). Cinco de 11 pacientes, com uma alta porcentagem de respiração oral ( > 25%), não obtiveram sucesso na titulação do CPAP com máscara oronasal. Durante limitação de fluxo aéreo estável o pico de fluxo inspiratório foi menor, o delta de pressão faríngea e a resistência inspiratória da via aérea superior foram maiores, enquanto as dimensões nas regiões retropalatal e retroglossal foram menores na rota oronasal comparada à nasal (p < 0,05 para todas as comparações). As diferenças foram observadas mesmo em pacientes sem respiração oral e foram abolidas quando selamos a boca do paciente com uma fita (n=6). Conclusão: Respiração oral e transmissão de pressão positiva pela cavidade oral comprometem a eficácia do CPAP com máscara oronasal / BACKGROUND: Continuous Positive Airway Pressure (CPAP) is the gold standard treatment for obstructive sleep apnea (OSA) and was conceived to be applied by nasal route only. Oronasal mask is frequently used in clinical practice but the effectiveness varies for unknown mechanisms. We hypothesized that oral breathing and pressure transmission through the mouth compromises oronasal CPAP efficacy. METHODS: Thirteen OSA patients, well adapted to oronasal CPAP, were monitored by full polysomnography, pharyngeal pressure catheter and nasoendoscopy. Patients slept with an oronasal mask with sealed nasal and oral compartments. Sleep was induced with low doses of midazolam. CPAP was titrated during both oronasal and nasal routes. CPAP was then reduced to induce stable airflow limitation and abruptly switched to the alternate route. In addition, a tape sealing the mouth was used to block pressure transmission to the oral cavity. RESULTS: Best titrated CPAP was higher in oronasal than nasal route (p=0.005). Five out of 11 patients with a high percentage of oral breathing ( > 25%) failed to achieve stable breathing during oronasal CPAP titration. During stable flow limitation, inspiratory peak flow was lower, driving pressure and upper airway inspiratory resistance were higher, retropalatal and retroglossal dimensions were smaller in oronasal compared to nasal route (p < 0.05 for all comparisons). Differences were observed even among patients with no oral flow and were abolished when a tape sealing the mouth was used (n=6). CONCLUSION: Oral breathing and transmission of positive pressure through the mouth compromises oronasal CPAP
108

Repercussões da máscara nasal e oronasal sobre a patência da via aérea superior durante uso de pressão positiva contínua para o tratamento de pacientes com apneia obstrutiva do sono / Impact of the nasal and oronasal mask on the patency of the upper airway during continuous positive airway pressure on treatment of patients with obstructive sleep apnea

Andrade, Rafaela Garcia Santos de 29 June 2016 (has links)
Introdução: A aplicação de Pressão Positiva Contínua nas Vias Aéreas Superiores (CPAP) durante o sono é o padrão ouro no tratamento da Apneia Obstrutiva do Sono (AOS) e foi primeiramente descrito utilizando uma máscara nasal. No entanto, na prática clínica a máscara oronasal é comumente. Este estudo foi desenhado para determinar os efeitos agudos da mudança de rota de fluxo do CPAP de nasal para oronasal e oral na patência da via aérea superior durante o sono em pacientes com AOS. Nós hipotetizamos que a pressão transmitida pelo compartimento oral da máscara oronasal pode comprometer a eficácia do CPAP no tratamento da AOS por empurrar a língua posteriormente. Métodos: Dezoito pacientes (idade 44 ± 9 anos, índice de massa corpórea de 33,8 ± 4,7 kg / m², índice de apneia-hipopneia 49,0 ± 39,1 eventos/hora) dormiram com máscara oronasal customizada com dois compartimentos (nasal e oral) selados e independentes conectados a uma válvula multidirecional. O sono dos pacientes foi monitorizado pela polissonografia e induzido por baixas doses de midazolam (3,1 ± 2,2 mg). O CPAP nasal foi titulado até a pressão de manutenção das vias aéreas superiores. A rota de fluxo do CPAP foi mudada de nasal para oronasal (n = 18) e oral (n = 16) durante o sono. A área retroglossal foi continuamente observada durante a nasoendoscopia. Resultados: O CPAP nasal (14,8 ± 4,1 cmH2O) foi suficiente para estabilizar a via aérea superior em todos os pacientes. Em contraste, o CPAP oronasal e oral promoveram eventos obstrutivos em 12 (66,7%) e 14 (87,5%) pacientes, respectivamente. Quando o CPAP foi transmitido pela rota oronasal e oral houve uma redução progressiva e significante na distância entre a epiglote e a base da língua e na área retroglossal em comparação com a respiração estável durante a rota nasal. Conclusões: Mudanças agudas na rota de fluxo do CPAP nasal para as rotas oronasal e oral induzem eventos obstrutivos e diminuem as dimensões da orofaringe em pacientes com AOS durante o sono. A máscara oronasal pode comprometer a efetividade do CPAP no tratamento da AOS / Introduction: Continuous Positive Airway Pressure (CPAP) is the gold standard treatment for obstructive sleep apnea (OSA) and was conceived to be applied by nasal route only. However, in clinical practice the oronasal mask is commonly used. This study was designed to determine the acute effects of changing the nasal CPAP route to oronasal and oral in upper airway patency during sleep in patients with. We hypothesized that the pressure transmitted by the oral compartment of oronasal mask will push the tongue backwards and will compromise CPAP effectiveness in OSA treatment. Methods: Eighteen patients with OSA (age: 44±9 years44±9 years44±9 years44±9 years44±9 years44±9 years44±9 years44±9 years44±9 years , body mass index: 33.8±4.733.8±4.733.8±4.7 33.8±4.7 33.8±4.7 Kg/m², apnea-hypopnea index: 49.0 ± 39.149.0 ± 39.149.0 ± 39.149.0 ± 39.149.0 ± 39.149.0 ± 39.1 49.0 ± 39.149.0 ± 39.149.0 ± 39.1 events/hour) slept with a customized oronasal mask with a nasal and oral sealed compartments connected to a multidirectional valve. Sleep was monitored by full polysomnography and induced by low dosis of midazolam (3.1 ± 2.2 mg). Nasal CPAP was titrated up to holding pressure and flow route was changed to oronasal (n = 18) and oral route (n = 16) during sleep. Retroglossal area was continuously observed by nasoendoscopy. Results: Nasal CPAP (14.8±4.1 cmH2O) was able to stabilize breathing in all patients. In contrast, CPAP delivered by oronasal and oral route promoted obstructive events in 12 (66.7%) and 14 (87.5%) patients, respectively. Compared to stable breathing during nasal route, there was a significant and progressive reduction in the distance between epiglottis and tongue base and the retroglossal area when CPAP was delivered by oronasal and oral route, respectively. Conclusions: CPAP delivered by oronasal route may compromise CPAP effectiveness to treat OSA
109

Desempenho dos estudantes de enfermagem na inserção de dispositivo supraglótico (máscara laríngea): um estudo randomizado e controlado em manequins / Performance of nursing students in the insertion of supraglottic device (laryngeal mask): randomized controlled trial on mannequins

Pedersoli, Cesar Eduardo 06 September 2013 (has links)
Estudo com objetivo de avaliar e comparar o desempenho teórico e prático de estudantes de enfermagem submetidos a estratégias de ensino-aprendizagem, aula expositivo-dialogada e atividade prática em laboratório de habilidades ou aula simulada, no manejo da via aérea em emergências por meio da máscara laríngea (ML). Estudo com delineamento experimental, abordagem quantitativa, de intervenção tipo Ensaio Clínico Randomizado Controlado. A população consistiu dos estudantes do oitavo período, bacharelado, da Escola de Enfermagem de Ribeirão Preto e a amostra de 17 estudantes, randomizados para grupo controle (GC) e grupo intervenção (GI). O GC foi submetido à aula expositivo-dialogada seguida de atividade prática em laboratório de habilidades com manequim de baixa fidelidade e o GI à aula simulada em laboratório utilizando o mesmo manequim. Elaboraram-se os instrumentos de avaliação escrita, cenário de simulação e avaliação clínica objetiva e estruturada no cenário de simulação (checklist), validados em aparência e conteúdo por comitê de juízes. A estratégia de coleta de dados foi Workshop intitulado \"Manejo da via aérea em emergências: uso da ML\". Foram avaliados teste escrito e OSCE (Exame Clínico Objetivo Estruturado) - avaliação clínica estruturada em Laboratório de Simulação, este último empregando como ferramenta o manequim de média-fidelidade. A atividade foi filmada e analisada por três avaliadores. Analisaram-se os desfechos: desempenho teórico no teste escrito e prático no OSCE, tempo de execução do OSCE, tempo para obtenção da primeira ventilação eficaz, número de tentativas para inserção da ML até obtenção de ventilação efetiva. Resultados: 16 estudantes eram do sexo feminino e um do sexo masculino, a idade média 24,4±4,2 anos. No pré-teste a nota média do GC de 6,6±1,0 e do GI de 6,5±0,5 e a mediana para ambos 6,5. No pós-teste a nota média do GC foi 8,4±0,8 (mediana 8,5), do GI de 8,6±1,1 (mediana 8,6). Comparando-se as médias obtidas no pré-teste por ambos os grupos, não há diferença estatisticamente significante (p=07427). Tal fato também pôde ser constatado no pós-teste (p=0,7117). Comparando as notas pré e pós-teste do GC evidenciou diferença estatisticamente significante (p=0,0025) o que também ocorreu para o GI (p=0,0002). A média no OSCE do GC foi 7,8±0,52 e GI 8,4±0,89; comparou-se tais notas verificando-se que não há diferença estatisticamente significante (p=0,0822). A média obtida pelo GC no pós-teste foi maior que a média obtida no OSCE e, para o GI, são equivalentes. O tempo médio de execução do OSCE pelo GC foi 479,8±183,3s (mediana 468,5s) e no GI 520,3±157s (mediana 506s), não havendo diferença estatisticamente significante (p=0,6311) e também para obtenção da primeira ventilação eficaz (p=0,9835). A média do nº tentativas para inserção da ML pelo GC 1,63±0,74 e GI 1,56±0,63. Embora os resultados não apontem diferença estatisticamente significante entre as médias dos grupos no pós-teste, para o GI os escores foram superiores. No presente estudo, apesar de diferentes estratégias de ensino abordarem o manejo da via aérea em emergências com a ML, os resultados demonstram que as mesmas foram eficazes e os objetivos de aprendizagem foram alcançados, pois houve incremento nas notas obtidas no pós-teste e no OSCE em ambos os grupos. / Study aimed to evaluate and compare the theoretical and practical performance of nursing students subjected to teaching and learning strategies, exhibition-dialogued class, and practical activity in skill lab or simulated class in airway management in emergencies through laryngeal mask (LM). This is a study of experimental design, quantitative approach, intervention type, Controlled Randomized Trials. The population consisted of students in the eighth semester from the Bachelor\'s Degree of the University of São Paulo at Ribeirão Preto College of Nursing and the sample consisted of 17 students, randomly assigned to the control group (CG) and the intervention group (IG). The CG was subjected to exhibition-dialogued class followed by practical activity in skill lab with low-fidelity mannequin and the IG to simulated class in the lab using the same mannequin. Written evaluation instruments, simulation scenario and objective structured clinical evaluation in simulation scenario (checklist) were developed and validated in appearance and content by a committee of judges. The strategy for data collection was the workshop entitled \"Airway management in emergencies: use of LM\". They were evaluates through written test and the OSCE (Objective Structured Clinical Examination) - structured clinical evaluation in Simulation Laboratory, the latter employing the medium-fidelity mannequin as tool. The activity was filmed and analyzed by three evaluators. The outcomes were analyzed: theoretical performance in written and practical test in the OSCE, the OSCE runtime, time to obtain the first effective ventilation, number of attempts to insert the LM to obtain effective ventilation. Results: 16 students were female and one male, mean age 24.4±4.2 years. In the pre-test the score average of CG was 6.6±1.0 and of IG was 6.5±0.5 and the median for both was 6.5. At post-test, the average score of CG was 8.4±0.8 (median 8.5), of IG was 8.6±1.1 (median 8.6). Comparing the averages obtained in the pre-test for both groups, there was no statistically significant difference (p=0.7427). This fact could also be observed in the post-test (p=0.7117). Comparing notes of pre and post-test of CG there was a statistically significant difference (p=0.0025) which also occurred for IG (p=0.0002). The mean of the OSCE for CG was 7.8±0.52 and for IG was 8,4±0,89; compared to such notes and it was verified that there is no statistically significant difference (p=0.0822). The average obtained by CG in the post-test was higher than the average obtained IG in the OSCE, and for IG they were equivalent. The average execution time of the OSCE for CG was 479.8 ± 183.3s (median 468.5s) and for IG 520.3±157s (506s median), with no statistically significant difference (p=0.6311) and also for obtaining the first effective ventilation (p=0.9835). The average of attempts to insert the LM by CG was 1.63±0.74 and by IG was 1.56±0.63 GI. Although the results do not indicate a statistically significant difference between the averages of the groups in the post-test, the scores were higher for IG. In this study, although different teaching strategies addressing airway management in emergencies through LM were used, the results show that they were effective and the learning objectives have been achieved, because there was an increase in the scores obtained in the post-test and in the OSCE in both groups.
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\"Movimento-imagem-ideia\" - o percurso de uma prática / \"Movement-Image-Idea\": the trajectory of a practice.

Vieira, Cristiane Paoli 09 November 2016 (has links)
Esta dissertação tem como objeto de estudo a elaboração do conceito, \"movimento-imagem-ideia\", desenvolvido no percurso de uma prática de improvisação. Iniciada no teatro, por meio dos aprendizados do jogo teatral, do jogo das máscaras, como a commedia dell\'arte e o palhaço, encontra a dança e as abordagens somáticas, ampliando-se e oferecendo estrutura à autonomia do intérprete improvisacional. As pesquisas cênicas que constituíram caminho e estabelecimento dessa conceituação, analisadas neste trabalho, têm por foco a improvisação e a máscara de A Troupe de Atmosfera Nômade; as improvisações em tempo real, diante do público, da Cia. Nova Dança 4; e a estrutura pré-fixada na dança, em Ladies, da inocência à crueldade, com possibilidades de rupturas improvisacionais. / This dissertation investigates the elaboration of a concept, \"movementimage- idea\", developed during an improvisation practice. When this improvisation - which started in the theatre with the use of theatre games, mask games, such as commedia dell\'arte and clowns - meets dance and somatic approaches, it is amplified, now offering structure to the autonomy of the improvisational actor. Previous research on performing arts that have paved a path to the establishment of the concept analyzed here focus on A Troupe de Atmosfera Nômade\'s use of improvisation and masks; Cia Nova Dança 4\'s real time improvisation in front of an audience; and the structure prefixed on dancing, in Ladies, from innocence to cruelty, with possible improvisational ruptures.

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