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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.
71

Diagnostic Imaging of Foreign Bodies and Compartmentalization in the Canine Manus

Ober, Christopher Patrick 24 April 2009 (has links)
Injury of the manus is an important cause of morbidity and function loss in dogs, especially working breeds. These injuries may cause foreign body retention and can lead to persistent infection. Accurate methods for diagnosis and localization of pathology in this anatomically complex region are critical to minimize patient morbidity, guide surgical planning, and improve case outcomes. The anatomy of the canine manus was evaluated with computed tomography (CT), magnetic resonance imaging (MRI), and transverse anatomic sections. Most structures identified on transverse sections were visible on both CT and MRI images. Detail in the osseous structures was better in CT images, while MRI provided increased contrast of soft-tissue structures. To test the hypothesis that diagnostic accuracies of CT, MRI, and ultrasound differ for detection of acute wooden foreign bodies in the canine manus, we inserted wooden splinters into canine cadaver manus and imaged each manus with all three modalities. Receiver operating characteristic curve analysis demonstrated that CT was most accurate for detection of acute wooden foreign bodies, followed in turn by ultrasound and MRI. Diseases in the human hand and foot are often confined by soft-tissue spaces, but similar structures have not been described in the dog. To determine if these spaces are present in the canine manus, we injected contrast medium into likely spaces and compartments in cadaver specimens, imaged the limbs with CT, and dissected the injected manus specimens. We found thirteen discrete soft-tissue spaces and five myofascial compartments that are similar to those described in the human hand. To test the hypothesis that spread of disease in the canine manus can be modeled and predicted, we injected cadaver interdigital web spaces with contrast medium, imaged them with CT, and dissected them. We found that the pattern of contrast agent spread, as a model of infection, was predictable and unique to the initial injection site. Findings from these cadaver studies improve our understanding of anatomy, imaging of wooden foreign bodies, and likely patterns of disease extension in the canine manus. Future studies are needed to test the utility of this information for surgical planning in affected clinical patients. / Ph. D.
72

A Combined Formal Model for Relational Context-Dependent Roles (Extended)

Kühn , Thomas, Böhme, Stephan, Götz, Sebastian, Aßmann, Uwe 17 September 2015 (has links) (PDF)
Role-based modeling has been investigated for over 35 years as a promising paradigm to model complex, dynamic systems. Although current software systems are characterized by increasing complexity and context-dependence, all this research had almost no influence on current software development practice, still being discussed in recent literature. One reason for this is the lack of a coherent, comprehensive, readily applicable notion of roles. Researchers focused either on relational roles or context-dependent roles rather then combining both natures. Currently, there is no role-based modeling language sufficiently incorporating both the relational and context-dependent nature of roles together with the various proposed constraints. Hence, this paper formalizes a full-fledged role-based modeling language supporting both natures. To show its sufficiency and adequacy, a real world example is employed.
73

Die Rolle der orbitalen MRT in der Differentialdiagnose von Erkrankungen der Augenmuskeln, des extrakonalen und subperiostalen Kompartimentes

Zhou, Quan 14 February 2003 (has links)
Orbitale Erkrankungen stellen für mehrere klinische Fachdisziplinen in Bezug auf Diagnostik und Therapie ein großes Problem dar. Die hochauflösende MRT (HR-MRT) ist in der Lage, eine detailierte Übersicht für die Orbitaanatomie und deren Abnormalitäten zu liefern. Aus diesem Grunde ist diese Studie durchgeführt worden, in der hochauflösenden MRT-Charakteristika von 224 Patienten mit orbitalen Erkrankungen beurteilt worden ist. Die Kriterien der Beurteilung sind: Lokalisation, Größe, Form, Rand, Ausdehnung und Veränderung der Nachbarstrukturen sowie die Signalintensitäten der Erkrankungen. Die Lokalisationskriterien sind sehr nützlich für die Differentialdiagnose orbitaler Erkrankungen der Augenmuskeln, dem extrakonalen und subperiostalen Kompartiment mittels der HR-MRT mit Oberflächenspule. Durch die Zuordnung zu einem Kompartiment kann die Differentialdiagnose grob eingeengt werden. Das subperiostale Kompartiment kann in Sinus, Meningen, orbitalen Knochen und subperiostalen Spaltraum weiter unterteilt werden. Mukozelen und Nasennebenhöhlentumoren sind nur in den Sinus zu finden, sämtliche Keilbeinmeningeome weisen einen Befall der Meningen auf. 83,3% Epidermoide und Dermoide liegen im orbitalen subperiostalen Raum mit einer engen Nachbarschaft zu einer Sutur. Die meisten Muskelbefälle der endokrinen Orbitopathie betreffen den inferioren und medialen geraden Muskel, die Verdickung des Muskelbefalls ist typischerweise nur im Muskelbauch ohne Muskelsehnebefall. Myositiden haben häufiger einen Muskelsehnebefall. Wenn eine Verdickung eines einzelnen Muskels den M. rectus lateralis betrifft, ist die Diagnose einer endokrinen Orbitopathie nicht wahrscheinlich. Rhabdomyosarkome liegen häufig im oberen inneren Quadranten der Orbita. Lymphome liegen meistens im frontalen Anteil des extrakonalen Kompartiment in Nachbarschaft zum Septum orbitale. Für eine weitere Differentialdiagnose sollen die morphologischen Kriterien verwendet werden. Auch die Große, Form und der Rand der orbitalen Erkrankungen können den wichtigen Hinweis zur Differentialdiagnose liefern. Ein reduziertes Muskelvolumen ist bei der Muskelatrophie und dem Trauma mit Muskel Einklemmung gesehen worden. Bei 11 von 128 endokrinen Orbitopathien ist das Volumen normal. Die meiste Erkrankungen gehen mit einer Volumenzunahme einher. Keilbeinmeningeome, Karziome der Nasennebenhöhlen, Rhabdomyosarkome und Lymphome haben große Volumina. Myositis und endokrine Orbitopathie mit Muskelbefall haben meist geringe oder mittlere Volumenzunahmen. Mukozelen, Epidermoid, Dermoid, Metastasen und Hämangiom können in allen Größenstufen gefunden werden. Epidermoide, Dermoide, Mukozelen, Hämangioperizytome, Hämangiome, Rhabdomyosarkome und Metastasen haben meist runde oder elliptische Formen, eine längliche Form wird bei orbitaler Myositis und endokriner Orbitopathie mit Muskelbefall beobachtet. Karzinome der Nasennebenhöhlen, Keilbeinmeningeome, Lymphome, endokrine Orbitopathie mit Fettbefall, Pseudotumoren und Phlegmone zeigen sich unregelmäßige Formen. Epidermoide, Dermoide, Mukozelen, Myositis, endokrine Orbitopathie, Hämangiome und Hämangioperizytome haben meistens einen scharfen Rand. Dagegen weisen Karziome der Nasennebenhöhlen, Lymphome, Keilbeinmeningeome, Rhabdomyosarkome, Metastasen, Pseudotumoren und Phlegmonen undeutliche Ränder auf.Die Verwendung der MRT-Signalintensit?ten zur Diffenrenzierung ist eingeschränkt, weil die meisten Läsionen sehr ähnliche Signalintensitäten zeigen. Es gibt aber einige Läsionen, die aufgrund ihrer Zusammensetzung besondere Signalintensitäten aufweisen, z.B. Blutungen, Melanin (paramagnetisch), Fett, Proteine, Wasser und Nekrosen. Mit einer Kontrastmittelgabe und dem Verhalten des Enhancements kann eine weitere Charakterisierung erfolgen. Bei den Veränderungen der Nachbarstrukturen sind vor allem die Knochenveränderungen am aussagekräftigsten. Epidermoide, Dermoide und Mukozelen sind meist mit Knochendefekten oder Kompressionsveränderungen verbunden, Keilbeinmeningeome stehen eng in Zusammenhang mit Knochenhyperplasien, Nasennebenhöhlenkarzinome sind immer mit Knochendestruktionen verbunden und Frakturen werden nur bei Traumata gesehen. Die raumfordernde Wirkung von Lymphomen ist nicht sichtbar, denn hier zeigt sich eine Diskrepanz zwischen einer oft charakteristischen, ausgedehnten Infiltration und nur einer geringen Verlagerung anderer Orbitastrukturen. Die klinische Krankengeschichte ist auch wesentlich zur Findung der Differentialdiagnose. Alle hier untersuchten Patienten mit Phlegmone und Trauma haben besondere Krankengeschichten. 70% Patienten mit Metastasen haben einen gesicherten Primärtumor in der Krankengeschichte. Alle Patienten mit endokriner Orbitopathie haben in der Anamnese eine Schilddrüsenerkrankung. Von diesen Patienten sind etwa 80% weiblich und 73% zwischen 30 und 60 Jahre alt. Rhabdomyosarkome treten hauptsächlich in der Kindheit auf. Pseudotumoren sprechen schnell und außerordentlich gut auf Steroidtherapien an. Somit kann eine Verbindung von Anamnese und MRT-Bildgebung wertvolle Informationen zur Differentialdiagnose liefern.Zur Differenzierung endokriner Orbitopathie und Myositis ist es nützlich die Lokation des Muskelbefalls (unilateral oder bilateral, Muskelsehne- oder Muskelbauchbefall, Einzelbefall oder Befall mehrerer Muskeln und Bevorzugung bestimmter Muskeln), die Ausdehnung (mit oder ohne Fettbefall), die Verlagerung des Augapfels, MRT-Signalintensitäten und die zeitliche Anamnese zu berücksichtigen. Zur Differenzierung Rhabdomyosarkom und Lymphome sollen das Alter, die Form der Läsionen und der Muskelbefall berücksichtigt werden. Zur Differenzierung zwischen Metastasen und Hämangiome können ihre klinische Krankengeschichte (mit oder ohne frühere Tumoren), der Rand der Läsionen, Muskelbefall und ihr MRT-Signal und das Ausmaß des Enhancements wertvolle Informationen liefern. Die einzige Differenzierungsmöglichkeit zwischen Epidermoid und Dermoid ist die MRT-Signalintensität (fettiger oder wässriger Inhalt der Läsion). Die Lokation ist am wichtigsten für die Differenzierung zwischen Epidermiod und Mukozelen. Für eine Differenzierung zwischen Keilbeinmeningeomen und Masennebenhöhlenkarzinome können ihre Lokationen, ihre Signalintensität, das Kontrasmittelverhalten und Veränderungen der Nachbarstrukturen den wichtigen Hinweis liefern. / The clinical diagnosis of orbital diseases is especially difficult because of the variety of tissues that built up the orbit and present with similar clinical presentation. High-resolution MRI (HR-MRI) has become an important modality for evaluation of the orbital diseases, due to its superb soft tissue resolution, direct multiplanar capability and lack of ionizing radiation. In this study, 224 patients with pathologically identified orbital diseases were evaluated retrospectively. The imaging characteristics of the orbital diseases on HR-MRI with surface coil were assessed. The analyzed criteria were: location, size, shape, margins, extension, adjacent structure, and signal intensity. Locazilation criteria in muscles, extraconal and subperiosteal compartments are very useful in the differential diagnosis of orbital tumors and other disease. If their locations are subdivided into greater detail, the differential diagnosis will be narrowed considerably. For example, the subperiosteal compartment can be subdivided into sinus, meninges, bone and subperiosteal space. Mucocele and carcinoma of nasal sinuses always occur in the nasal sinuses. Sphenoidal meningiomas occur in the meninges, and epidermoid and dermoid are found to 83.3% in the orbital subperiosteal space near the bone sutures and show bony defects or thinning and sclerosis. The most frequently involved muscles in thyroid orbitopathy are the inferior rectus and the medial rectus muscles. Typically, the muscle enlargement involves the muscle belly and spares its tendinous portion. While orbital myositis most frequently involves the lateral rectus muscles in particular the muscles' tendon. When isolated lateral rectus muscle enlargement is present, another etiology rather than thyroid orbitopathy should be considered. Within the extraconal compartment the upper inner quadrant is the most common site of rhabdomyosarcoma. While lymphomas mostly occur in the anterior orbit, posterior to the orbital septum. For further differentiation, morphological criteria can be employed, such as the size, shape, and margin help to make the differential diagnosis. Reduced muscle volume is characteristic in the atrophic muscle. The shortened muscle length occurs in traumas connected with muscle incarcerations. Disease without volume changes may happen in thyroid orbitopathy with the involvement of the muscle or the fat tissue. All the other diseases have a enlarged volume of lesion. The size of Sphenoidal meningioma, carcinoma of nasal sinuses, lymphoma and rhabdomyosarcoma is greatly enlarged. While the size-distribution of mucoceles, epidermoids and dermoids show no difference. But orbital myositis and thyroid orbitopathy have slight to moderate enlarged volume of involved muscles. Concerning the pathology shape mucoceles, dermoids, epidermoids, haemangiomas, and metastases are round or elliptical. The orbital myositis and thyroid orbitopathy with muscle involvement show long shapes. Lymphomas and the thyroid orbitopathy with fat tissue involvement have mostly irregular shapes. The poor-defined margin is often seen in malignant lesions, infections or inflammations, such as a paranasal carcinomas, lymphomas, rhabdomyosarcomas, pseudotumors and phlegmon. While the sharp delineation suggests a benign process, such as a mucocele, dermoid, epidermoid, haemangioma, thyroid orbitopathy and myositis. The use of MRI signal intensity for a differential criterion may be limited, because most diseases have the same signal intensity on MR imaging. Thus it seems to be that signal intensity patterns are usually not specific for the differentiating of diagnose. However, MRI may have some specificity for certain lesions based on signal intensity patterns, especially in those containing hemorrhage, paramagnetic melamin, fat, protein, water, enlarged vessels, and necrosis. With contrast enhancement MRI further contributes to the characterization of various types of lesions within the orbit. It can be made a definitive diagnosis for the dermoid (contains fat), cholesterolcyste, meningioma, lymphangioma (contain hemorrhage), haemangioma, metastasis of melanoma, thyroid orbitopathy with active edema and chronic fibrosis, hematoma and emphysema due to a trauma. Another criterium is the adjacent structure changes. Out of them, the bone changes are very important. Epidermoid, dermoid, and mucocele are often accompanied by bone defects or pressure changes. The sphenoidal meningioma is frequently accompanied by bone hyperplasia. Bone fractures are seen in traumas. Malignant tumors are almost associated with bone destruction when they involve the orbit, e.g., the carcinoma of the nasal sinuses. The effect of occupying space in lymphomas causes mismatch with the size, which often has greater volume. It mostly infiltrates tissue, but it seldom produces mechanical shift to adjacent structures. Clinical history is essential and occasionally it provides a clue that alters the boundary of differential diagnoses and redirects the investigation toward possibilities that had not been previously entertained. Patients with metastases have a definite primary tumor history to 70%. The knowledge of previous malignancy is important for the diagnoses of orbital metastasis. All the patients with thyroid orbitopathy, phlegmon, pseudotumor and trauma have also special clinical histories or symptoms. The rhabdomyosarcoma and capillary hemangioma are the most common orbital tumors in children, while the cavernous hemangioma is the most common orbital vascular tumor in adults. Thyroid orbitopathy occurs with highest prevalence in females with middle age. Orbital pseudotumors usually show a dramatic resolution under steroid therapy. In fact, its final diagnosis is often based on response to steroids. When combined with clinical history and examination, radiologic imaging can provide valuable information regarding the diagnosis and differential diagnoses. For the differentiation of the thyroid orbitopathy and myositis it is useful to take their locations (unilateral or bilateral, tendon involvement or not, single or multiple muscles involvement, and which muscles involvement), sizes, extensions (with or without fat-infiltration), and MRI signal intensities into account; For the differentiation of rhabdomyosarcomas and lymphomas clinical history (ages), the shape of the lesions, and the adjacent structure changes (muscles infiltration) are of diagnostic interest. Clinical history (with or without previous malignancy), the margin of the lesion, their adjacent structure changes (muscles infiltration), and MRI signal intensities help to discriminate between metastases and hemangiomas. The only difference between epidermoid and dermoid is their MRI signal intensities (with or without fat). Location is important to differentiate the epidermiod and mucocele. Locations, adjacent structure changes and MRI signal intensities can provide valuable information to distinguish between sphenoidal meningioma and carcinoma of nasal sinuses. The different shape, margin, adjacent structure change, and MRI signal intensity between the carcinoma of nasal sinuses and mucocele are of diagnostic help.
74

A Combined Formal Model for Relational Context-Dependent Roles (Extended)

Kühn, Thomas, Böhme, Stephan, Götz, Sebastian, Aßmann, Uwe 17 September 2015 (has links)
Role-based modeling has been investigated for over 35 years as a promising paradigm to model complex, dynamic systems. Although current software systems are characterized by increasing complexity and context-dependence, all this research had almost no influence on current software development practice, still being discussed in recent literature. One reason for this is the lack of a coherent, comprehensive, readily applicable notion of roles. Researchers focused either on relational roles or context-dependent roles rather then combining both natures. Currently, there is no role-based modeling language sufficiently incorporating both the relational and context-dependent nature of roles together with the various proposed constraints. Hence, this paper formalizes a full-fledged role-based modeling language supporting both natures. To show its sufficiency and adequacy, a real world example is employed.
75

Funktionsbeskrivning av brandlarmsstyrningen i ventilationssystemet ombord korvett av Göteborgsklass

Jonsson, Jesper January 2010 (has links)
Denna slutrapport beskriver projektarbetet Funktionsbeskrivning av Brandlarms-styrningen av Ventilationssystemet ombord Korvett av Göteborgsklass som beställdes av divisionsingenjören vid 41.korvettdivisionen. Bakgrunden till projektets beställning var att fartygens dokumentation över ventilationssystemets funktion vid brand var bristfällig vilket försvårade underhåll, felsökning och utbildning av och på systemet. Den ofullständiga dokumentationen var ett resultat av att individerna i fartygs­klassen modifierats i flera olika omgångar utan att dokumentationen uppdaterats på ett tillfredsställande sätt. Det hade även framkommit att det fanns olikheter i konfigurationen av fartygsindividernas system. Projektet genomfördes dels genom studier av den befintliga dokumentation som fanns att tillgå ombord och på divisionen, dels genom praktiska under­sökningar ombord på fartygen. Under de praktiska undersökningarna framkom behov av ytterligare utredningar än de som ursprungligen framgick av det erhållna uppdraget. Projektet påvisade skillnader mellan fartygens system, vissa förmodat felaktiga styr­ningar av fläktar och spjäll samt fastställde att dokumentationen var bristfällig. Projektet resulterade i ett antal beskrivande dokument som sammanställdes i en pärm för respektive fartyg. Dessa uppfyller det givna uppdraget och målen med projektet. En större modifiering av fartygen i klassen med syfte att förlänga deras operativa livslängd är under planeringsstadiet. Under modifieringen skall bland annat fartygens dokumen­tation uppdateras, något som resultaten från detta projekt kommer underlätta. / This is the final report regarding the project A Functional Description of the Fire Alarm Con­trol in the Ventilation System aboard the Swedish Navy’s Gothenburg-class Corvettes, wh­­ich was commissioned by the Senior Marine Engineer Officer of the 41st Corvette Sq­­ua­d­ron of the 4th Naval Warfare Flotilla. The reason for the commission was that the set of documentation concerning the function of the ventilation system in case of a fire was insufficient. This caused problems, both during maintenance work done to en­­­su­re that the system was operating in accordance with the design parameters, as well as when trouble-shooting the system. The insufficient set of documentation was a result of a number of upgrades done to the ships over the ye­ars without any corr­e­s­p­on­ding up­date of the documentation. During the project it has also been made clear that there were non-documented differences existing be­­tween the ships in the class. The project was fulfilled by a combination of studies of the existing set of do­cumen­tation and practical surveys aboard the ships. During the surveys, more short­comings in the existing set of documentation became evident. The project demonstrated differences between the individual ships, assumed inaccuracies in the control of fans and dampers and determined the shortage in the set of documentation. The project has resulted in a number of describing documents that are collected in one unique file for each ship. These documents fulfil the commission and the objectives of the project. A major upgrade of the ships in the class with the purpose of extending their operational lifetime is now being planned. The ships’ set of documentation will be simultaneously updated, a task that will be simplified with the support of the results of this project.
76

Improved pharmacometric model building techniques

Savic, Radojka January 2008 (has links)
<p>Pharmacometric modelling is an increasingly used method for analysing the outcome from clinical trials in drug development. The model building process is complex and involves testing, evaluating and diagnosing a range of plausible models aiming to make an adequate inference from the observed data and predictions for future studies and therapy. </p><p>The aim of this thesis was to advance the approaches used in pharmacometrics by introducing improved models and methods for application in essential parts of model building procedure: (i) structural model development, (ii) stochastic model development and (iii) model diagnostics. </p><p>As a contribution to the structural model development, a novel flexible structural model for drug absorption, a transit compartment model, was introduced and evaluated. This model is capable of describing various drug absorption profiles and yet simple enough to be estimable from data available from a typical trial. As a contribution to the stochastic model development, three novel methods for parameter distribution estimation were developed and evaluated; a default NONMEM nonparametric method, an extended grid method and a semiparametric method with estimated shape parameters. All these methods are useful in circumstances when standard assumptions of parameter distributions in the population do not hold. The new methods provide less biased parameter estimates, better description of variability and better simulation properties of the model. As a contribution to model diagnostics, the most commonly used diagnostics were evaluated for their usefulness. In particular, diagnostics based on individual parameter estimates were systematically investigated and circumstances which are likely to misguide modelers towards making erroneous decisions in model development, relating to choice of structural, covariate and stochastic model components were identified. </p><p>In conclusion, novel approaches, insights and models have been provided to the pharmacometrics community. </p><p>Implementation of these advances to make model building more efficient and robust has been facilitated by development of diagnostic tools and automated routines.</p>
77

A probabilistic comparison of times to flashover in a compartment with wooden and non-combustible linings considering variable fuel loads

Studhalter, Jakob January 2012 (has links)
Prescriptive fire safety codes regulate the use of combustible room linings to reduce fire risk. These regulations are based on classification systems which designate materials according to their relative hazard when exposed to a standard fire scenario. However, no quantitative data sets on the fire risk of wooden lining materials exist which take into account relevant uncertainties, such as movable fuel loads in compartments. This work is a comparative risk analysis on the influence of wooden linings on the time to flashover in a compartment, considering uncertainties in the fuel load configuration. A risk model is set up for this purpose using B-RISK, a probabilistic fire design and research tool currently under development at BRANZ (Building Research Association of New Zealand) and the University of Canterbury. The risk model calculates fire spread in a compartment between fuel load items and from fuel load items to combustible linings. Multiple iterations are performed considering varying fuel load arrangements and input values sampled from distributions (Monte-Carlo simulation). The functionality and applicability of the risk model is demonstrated, comparing the model with experiments from the literature. The model assumptions are described in detail. Some of the model inputs are defined as distributions in order to account for uncertainty. Parametric studies are conducted in order to analyse the sensitivity of the results to input parameters which cannot be described as distributions. Probabilistic times to flashover are presented and discussed for an ISO 9705 compartment considering varying movable fuel loads and different lining configurations. The fuel load is typical for a hotel room occupancy. Effects of suppression measures are not considered. It is shown that flashover occurs approximately 60 seconds earlier if walls and ceiling are lined with wooden materials than if all linings are non-combustible. This value refers to the 5th percentiles of the time to flashover, i.e. in 5% of the cases flashover has occurred and in 95% of the cases flashover has not (yet) occurred. Referring to 50th percentiles (median values), the difference is approximately 180 seconds. Furthermore it is shown that with wooden wall and ceiling linings in approximately 95% of the iterations flashover occurs, whereas with non-combustible linings 86% of the iterations lead to flashover. After 900 seconds, in 90% of the iterations flashover occurs if walls and ceiling are lined with wooden materials, and in 77% of the iterations if the linings are non-combustible. Using different wooden lining materials (non-fire retardant plywood, fire retardant plywood, and MDF) has no significant effect on the probabilistic times to flashover. Varying the fuel load energy density has an influence only when all linings are non-combustible and when the fuel load energy density is relatively low (100–200 MJ/m2). This work contains recommendations regarding the further development of B-RISK, the research into the fire risk connected with wooden room linings, and suggestions regarding the further development of prescriptive fire safety codes.
78

Medida da pressão intra-abdominal após colocação de compressas ao redor do fígado: estudo experimental em porcos / Intra-abdominal pressure measurement after sponge placement around the liver: experimental study in pigs

Akamine, Masahiko 27 May 2009 (has links)
INTRODUÇÃO: A síndrome compartimental abdominal (SCA) é uma complicação frequente da cirurgia de controle de dano, podendo ocorrer em até 33% dos casos. A medida da pressão intra-abdominal para diagnóstico da SCA é avaliada através da pressão intravesical. OBJETIVO: Avaliar, através de modelo experimental, as repercussões da colocação de compressas sobre a pressão intravesical e em diferentes regiões do abdome. MÉTODO: Foram utilizados 10 porcos machos, entre 45 e 60 dias, com peso entre 15 e 18 kg, submetidos a laparotomia exploradora para colocação de compressas e avaliação de medidas de pressão no espaço supra-hepático (Psh), espaço infra-hepático (Pih), espaço subfrênico esquerdo (Psfe), veia cava inferior (Pvci), veia porta (Pvp) e bexiga (Pv). Foi também avaliada a pressão arterial média (PAM) e o débito cardíaco. As diferentes medidas de pressão foram comparadas no mesmo animal com diferentes tipos de fechamento da parede abdominal: bolsa de Bogotá (CCB), total da aponeurose (CCAF), pele (CCPF) e total da pele e aponeurose (CF). Os resultados foram submetidos a análise estatística. RESULTADOS: Não houve diferença (p>0,05) entre as medidas de PAM em todas as fases de fechamento do abdome. A pressão de veia cava inferior e a pressão intravesical foram diferentes (p<0,05) entre os grupos CF e CCAF. Psfe, Psfd e Psh foram diferentes (p<0,05) entre CF e CCB, CF e CCPF e CF e CCAF. Foram diferentes (p<0,05) Pv e Psfd, Pv e Psh e Psfe e Psfd nos grupos CCB, CCPF e CCAF. No grupo CCAF ainda foram diferentes (p<0,05) Pv e Psfe e Psh e Psfd. A avaliação de Pvp mostrou-se diferente (p<0,05) em relação ao grupo controle (CF) nos grupos CCB, CCPF e CCAF, e ainda entre CCB e CCAF. CONCLUSÃO: A pressão intra-abdominal não é uniforme quando são colocadas compressas na cavidade peritoneal. A pressão vesical é menor que em outras regiões da cavidade peritoneal. As pressões não ultrapassaram níveis de Síndrome Compartimental Abdominal. / INTRODUCTION: Abdominal compartment syndrome is a frequent complication of damage control surgery and can occur in approximately 33% of cases. Diagnosis of abdominal compartment syndrome depends on measurement of abdominal pressure which is usually assessed through intravesical pressure. OBJECTIVE: Evaluate the consequences of liver packing with sponges to the intravesical pressure and to pressures in different sites of the abdomen in an animal experimental model. METHODS: 10 adult male pigs, aged 45 to 60 days, weighing 15 to 18 kg, underwent laparotomies for liver packing and evaluation of pressures in suprahepatic space (Psh), infrahepatic space (Pih), left subphrenic space (Psfe), inferior vena cava (Pvci), portal vein (Pvp) and bladder (Pv). Other variables such as mean arterial pressure and cardiac output, were also measured. Different pressure measurements were compared in the same animal with different types of closures of the abdominal wall: Bogota bag (CCB), total closure of aponeurosis (CCAF), skin closure (CCPF) and total skin and aponeurosis closure (CF). Results were analyzed statistically. RESULTS: There was no difference (p>0,05) between mean arterial blood pressure in all phases of abdominal closure. Pressure in inferior vena cava and intravesical pressure were different (p<0,05) in groups CF and CCAF. Psfe, Psfd and Psh were different (p<0,05) between CF vs CCB, CF vs CCPF and CF vs CCAF. Pv vs Psfd, Pv vs Psh and Psfe vs Psfd were different (p<0,05) in groups CCB, CCPF and CCAF. In group CCAF, Pv vs Psfe and Psh vs Psfd were also different (p<0,05). Evaluation of Pvp has shown to be different (p<0,05) when compared to control group (p<0,05) in groups CCB, CCPF and CCAF, and also between CCB and CCAF. CONCLUSION: Intra-abdominal pressure is not uniform when sponges are placed in the abdomen. Intravesical pressure is lower than pressures in other sites of the peritoneal cavity. No pressure measurement reached levels of abdominal compartment syndrome.
79

Room/Corner Fire Calibration Data: Marine Composite Screening Specimens

Alston, Jarrod John 27 May 2004 (has links)
Compartment fire scenarios are of great interest due to the large loss of life and property that occurs annually in such fires. Due to the current move towards performance-based building code standards and the increasing acceptance by the regulatory system of model results, there is a growing need for detailed compartment fire data to demonstrate the accuracy of such engineering tools as they are used to ascertain performance. A series of carefully designed full-scale room/corner tests on two vinyl ester resin composite systems have been conducted in a heavily instrumented compartment to provide compartment fire data for the calibration of engineering tools. The two composite systems were chosen based on their thermal behavior. A nominally thermally-thick glass-reinforced plastic (GRP) skin was desirable, as many analytical formulations have been developed using semi-infinite assumptions. A "thermally-thin" skin panel typical of that used in fast ferry construction, consisting of a GRP skin over a balsa core, was also tested. The test protocol used throughout the room/corner experiments was a modification of the ISO 9705 standard where the HRR of the ignition fire was varied according to the Critical Ignition Source Strength concept. To date, there has been little work done where heat fluxes from compartment fires have been measured. Therefore, one of the key data components developed in this series of tests are heat flux measurements from thin skin calorimeters. A total of twenty-five thin skin calorimeters, constructed of Inconel plates, were located throughout the room: the spatial distribution of net and incident heat fluxes within compartment for both pre- and post-flashover conditions have been determined. Additionally, rakes of bare-bead thermocouples were placed in the vent and the corner of the room coincident with the thin skin calorimeter arrays. A third rake was placed in the center of the room. The thermocouple arrays provide data regarding layer temperatures and interface heights as well as a limited determination of temperature spatial distribution within the compartment. The thermocouple rakes also permit calculation of pressure gradients across and mass flows through the vent, thus providing information regarding wall lining fire entrainment rates, of use in corner fire algorithm validations and for globally evaluating the accuracy of CFD codes. Bench-scale cone calorimeter (ASTM E1354, ISO 5660) tests have been carried out on the two composite systems to gather material fire properties necessary as model inputs for fire spread algorithms. The present study developed material properties including heat release rate, species production, and ignition data for the two composite systems. Included are uncertainty bands that account for calculation and instrument uncertainty.
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Compartimentação da paisagem via relevo e rede de drenagem e sua relação com atributos e classes de solos / Landscape compartmentation through relief and drainage network and its relation with soil attributes and soil classes

Mello, Fellipe Alcantara de Oliveira 30 January 2019 (has links)
As fotografias aéreas, bem como as técnicas de estereoscopia, foram amplamente utilizadas para estudos ambientais e da paisagem. Com o avanço do mapeamento digital de solos os parâmetros da rede de drenagem foram sendo substituídos por parâmetros derivados do relevo, nas metodologias de predição de atributos do solo. No entanto, a literatura é ampla na atribuição da rede de drenagem como um fator determinante no mapeamento de solos, havendo a necessidade de desenvolver técnicas para inserir as características dos canais nos diferentes métodos de mapeamento do solo. Dessa forma, objetiva-se desenvolver um mapa de compartimentação da paisagem, através da rede de drenagem e um modelo digital de elevação (MDE), ambos com alta resolução espacial, visando avaliar as suas correlações com os atributos do solo (teor de argila nas profundidades 0-20 e 80-100 cm, gradiente textural, Ferro total (Fe2O3) e a cor do solo) e classes pedológicas. Tais procedimentos poderão auxiliar na produção de métodos base para relacionar a paisagem com a pedologia e o mapeamento. A área de estudo está localizada no município de Rio das Pedras, no estado de São Paulo, Brasil, com 538 km². O levantamento da rede de drenagem foi realizado a partir de fotografias aéreas com a visualização em 3D por estereoscopia digital. O MDE foi criado a partir de curvas altimétricas com equidistância vertical de 5 m. A partir das características da rede de drenagem e do relevo foram calculados os parâmetros morfométricos que representassem os dois elementos ao longo de toda a área de estudo. Com o processamento dos parâmetros foi utilizada a técnica fuzzy k-médias para fazer uma compartimentação da paisagem não supervisionada. Os resultados mostraram que a densidade de drenagem (DD) possui uma correlação negativa com os teores de argila (r = - 0.63), enquanto a correlação com o gradiente textural foi positiva (r = 0.42). O ferro total (Fe2O3) apresentou baixa variabilidade na área e não resultou em correlações significativas. A maior correlação foi com o matiz (r = 0.67), determinando solos mais amarelos nos locais de maior DD. A compartimentação da paisagem separou bem as posições do relevo em relação a DD. Cada compartimento se apresentou como uma unidade de mapeamento, havendo relação direta com classes pedológicas. / Aerial photographs, as well as stereoscopy were widely used for environmental and landscape studies. As digital soil mapping techniques have been developed, drainage network was replaced for relief parameters. However, literature studies have shown vast attribuition between drainage network and soil mapping, bringing the need to develop ways to insert the drainage parameters on different soil mapping strategies. Therefore, this study aims to create a landscape compartment map through drainage network and a digital elevation model (DEM), both with high spatial resolution, in order to evaluate its correlation with five soil attributes (clay content at 0-20 and 80-100 cm, textural gradient, total Iron (Fe2O3) and color) and soil classes. Wih these procedures it will be possible to create base methods to associate landscape with pedology and mapping. The study area has 538 km² and is located at Rio das Pedras municipality in the state of São Paulo, Brazil. The drainage network was created using aerial photographs with digital stereoscopy in 3D and the DEM with altimetric curves. These two geographic basis were used to calculate morphometric parameters that represents the patterns along the study area. The parameters were processed with fuzzy k-means technique to create a non-supervised landscape compartments map. Results showed that drainage density (DD) had a negative correlation with clay content (r = - 0.63), while textural gradient was positive (r = 0.42). The (Fe2O3) had low spatial variability, resulting in non-significant results. The greatest correlation was achieved with soil color (r = 0.67), indicating yellow soils at high DD landscapes. The landscape compartment was able to distinguish the relief positions related to DD. Each compartment was assumed as a soil map unit, presenting straight connections with soil classes.

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