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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.
31

Metody přesného měření nízkých impedancí / Methods of Accurate Measurement of Low Impedances

Mašláň, Stanislav January 2021 (has links)
Overall topic of presented thesis is development of methods of measurement of low impedances below 10 Ohm in a frequency range up to 1 MHz. The thesis comprises of three main parts. First part of thesis describes design of unique and simple calculable standards of resistance that are used for calibration of the bridge and as the reference standards for the calibrations. Next part of theses is focused on design of digital sampling bridge in various topologies suitable for measurement of various types of impedance standards up to frequency of 1 MHz. The thesis describes the HW components, data processing and corrections scheme allowing the designed bridge to reach expanded uncertainties (k=2) below 0.005% and 250 µrad at 1 MHz. One of the key points of the proposed corrections scheme is unique automatic linearity calibration method requiring minimal operator's effort. The theses also describes integration of Spice model of the bridge the bridge SW that allowed validation of functionality of the bridge and also analysis of uncertainty contributions related to interferences between the bridge components. The last part of the thesis shows selection of measurements of known impedances and international comparisons that proofs performance of the bridge.
32

The application of Eulerian laser Doppler vibrometry to the on-line condition monitoring of axial-flow turbomachinery blades

Oberholster, Abraham Johannes (Abrie) 24 June 2010 (has links)
The on-line condition monitoring of turbomachinery blades is of utmost importance to ensure the long term health and availability of such machines and as such has been an area of study since the late 1960s. As a result a number of on-line blade vibration measurement techniques are available, each with its own associated advantages and shortcomings. In general, on-blade sensor measurement techniques suffer from sensor lifespan, whereas non-contact techniques usually have measurement bandwidth limitations. One non-contact measurement technique that yields improvements in the area of measurement bandwidth is laser Doppler vibrometry. This thesis presents results and findings from utilizing laser Doppler vibrometry in an Eulerian fashion (i.e. a fixed reference frame) to measure on-line blade vibrations in axial-flow turbomachinery. With this measurement approach, the laser beam is focussed at a fixed point in space and measurements are available for the periods during which each blade sweeps through the beam. The characteristics of the measurement technique are studied analytically with an Euler-Bernoulli cantilever beam and experimental verification is performed. An approach for the numerical simulation of the measurement technique is then presented. Associated with the presented measurement technique are the short periods during which each blade is exposed to the laser beam. This characteristic yields traditional frequency domain signal processing techniques unsuitable for providing useful blade health indicators. To obtain frequency domain information from such short signals, it is necessary to employ non-standard signal processing techniques such as non-harmonic Fourier analysis. Results from experimental testing on a single-blade test rotor at a single rotor speed are presented in the form of phase angle trends obtained with non-harmonic Fourier analysis. Considering the maximum of absolute unwrapped phase angle trends around various reference frequencies, good indicators of blade health deterioration were obtained. These indicators were verified numerically. To extend the application of this condition monitoring approach, measurements were repeated on a five-blade test rotor at four different rotor speeds. Various damage cases were considered as well as different ELDV measurement positions. Using statistical parameters of the abovementioned indicators as well as time domain parameters, it is shown that with this condition monitoring approach, blade damage can successfully be identified and quantified with the aid of artificial neural networks. / Thesis (PhD)--University of Pretoria, 2010. / Mechanical and Aeronautical Engineering / unrestricted
33

Mission Planning for the in-orbit Lunar calibrations of the MicroCarb instrument / Rymduppdragsplanering för månkalibreringar av MicroCarb-instrumentet i omloppsbana

Caffier, Erwan January 2021 (has links)
In-orbit calibrations of space instruments are often necessary to ensure the accuracy of the measurements. The Moon provides a target with very predictable characteristics. In this report, the opportunities to perform in-orbit lunar calibrations of the MicroCarb instrument are evaluated and a procedure for conducting the Mission Planning for these calibrations is developed. Through modeling the spacecraft in its orbit, simulations show that continuous observation sequences of up to 48 minutes can be expected each lunation. The variability of the optical properties of the Moon during an opportunity is related to the orientation of the plane of the orbit of the spacecraft with respect to the cone with axis the Moon-Sun direction and apex the center of the Moon that contains the spacecraft. Choosing a value of the phase angle (Sun-Moon-Spacecraft angle) around −20 degrees to plan the lunar calibrations allows to minimize the variations of apparent radiance of the Moon during the observation. The results make it possible to refine the choice of the best moments to plan the lunar calibrations. This also allows the satellite operations team to anticipate the planning of lunar calibrations on the scale of several months. / Kalibreringar i omloppsbana för rymdinstrument är ofta nödvändiga för att säkerställa mätningarnas noggrannhet. Månen utgör ett kalibreringsmål med mycket förutsägbara egenskaper. I denna rapport utvärderas möjligheterna att utföra månkalibreringar i omloppsbana för MicroCarb-instrumentet och ett förfarande för genomförande av uppdragsplanering för dessa kalibreringar har utvecklats. Genom att modellera rymdfarkosten i sin bana visar simuleringar att kontinuerliga observationssekvenser på upp till 48 minuter kan förväntas varje månvarv. Variationen hos de optiska egenskaperna för månen under ett tillfälle är relaterad till orienteringen av rymdfarkostens plan i förhållande till konen med axeln för månen-solens riktning. Att välja ett värde för fasvinkeln (Sun-Moon-Spacecraft-vinkel) på runt −20 grader vid planering av månkalibreringarna gör det möjligt att minimera variationerna i månens strålning under observationen. Resultaten gör det möjligt att förfina valet av de bästa tidpunkterna för månkalibreringarna. Detta gör det också möjligt för satellitoperationsteamet att förutse planeringen av månkalibreringar flera månader framåt.
34

Parâmetros de avaliação nutricional para detectar desnutrição em pacientes com AIDS em tratamento com antirretrovirais / Nutritional assessment parameter to detect malnutrition in Aids patients on retroviral therapy

Carla Alexandra Almeida Salmazo 11 August 2010 (has links)
A avaliação do estado nutricional em pacientes com HIV é de grande importância, pois as conseqüências provocadas pelo processo patológico da doença estão associadas com perda de peso corporal, massa magra e desnutrição grave, o que prediz aumento da morbimortalidade. Os valores de linfometria CD4 também têm sido utilizados como preditores a curto e médio prazo para o desenvolvimento de infecções oportunistas, as quais são incomuns em pacientes com CD4 >200 cels/mm3. Partindo deste conhecimento, optou-se por estudar o estado nutricional de homens e mulheres HIV positivos de acordo com a contagem de células CD4. Utilizou-se como parâmetros nutricionais o índice de massa corporal (IMC), a área muscular do braço corrigida (AMBc), albumina sérica e o ângulo de fase (AF). Foram estudados 39 pacientes HIV positivos, acompanhados pelo ambulatório de doenças infectoparasitárias do Hospital Universitário Pedro Ernesto (HUPE/UERJ). Não foi observada desnutrição na população estudada, quando avaliada pelo IMC e albumina em ambos os sexos, independente do número de células CD4. Entretanto, a AMBc e o AF, tanto nos homens quanto nas mulheres, demonstraram comprometimento nos parâmetros de massa magra. Em relação à associação entre os indicadores nutricionais e o número de células CD4, foi observado correlação significante com a AMBc e a albumina no grupo estudado. A correlação de acordo com o sexo manteve-se significante em ambos os grupos para AMBc e com uma tendência positiva (p=0,06) entre o AF e CD4 no grupo dos homens. Portanto, estes resultados demonstram que para avaliar o estado nutricional, principalmente o compartimento de massa corporal magra de pacientes HIV positivos sob terapia antirretroviral, é preciso utilizar indicadores mais sensíveis, mesmo naqueles pacientes com melhor estado de controle da doença. / The assessment of nutritional status in patients with HIV is of great importance, because the consequences caused by the pathological process of the disease are associated with weight loss, lean body mass and severe malnutrition, which predicts increased morbidity and mortality. The values of CD4 linfometria have also been used as predictors of short and medium term development of opportunistic infections, which are uncommon in patients with CD4 counts > 200 cells/mm3. Based on this knowledge, we chose to study the nutritional status of HIV positive men and women according to CD4 cell count. Participants had the following nutritional parameters assessed: body mass index (BMI), corrected arm muscle area (AMA), serum albumin and the phase angle (PA). We studied 39 HIV-positive patients, under treatment in a infectious diseases clinic of the University Hospital Pedro Ernesto (HUPE). None of patients has malnutrition according BMI and albumin in both sexes, regardless of the number of CD4 cells. However, in men and women to AMA and the PA, have demonstrated reductions in parameters of lean body mass. Regarding the association between nutritional indicators and the number of CD4 cells, we observed a significant correlation with the AMA and albumin in the study group. The correlation according to gender remained significant in both groups for AMA and a positive trend (p = 0.06) between the PA and CD4 in males. Therefore these results demonstrate that to assess nutritional status, especially the compartiment of lean body mass in HIV positive patients under antirretrovirals, it is necessary to use more sensitive, even in patients with the best state of disease control.
35

Auswirkungen des Ernährungszustandes auf die Verträglichkeit einer Chemotherapie bei Patientinnen mit gynäkologischen Malignomen

Spaniol, Ulrike I. L. 17 May 2004 (has links)
In der klinischen Diagnostik gewinnt die Untersuchung des Ernährungszustandes zunehmend an Bedeutung. Denn die Güte des Ernährungszustandes hat einen Einfluss auf die Mortalität und Morbidität der Patienten. Zur groben Evaluierung des Ernährungszustandes dient der Body Mass Index (BMI). Eine differenzierte Beurteilung des Ernährungszustandes wird durch die Analyse der Körperzusammensetzung erreicht. Die phasensensitive bioelektrische Impedanzanalyse (BIA) ist eine schnelle, preisgünstige und nicht-invasive Methode zur Messung der Körperzusammensetzung. Insbesondere der Phasenwinkel, der ein direkter Messparameter der BIA ist, gibt einen schnellen Überblick über den Ernährungszustand der Patienten. Er spiegelt das Verhältnis von Extrazellulärmasse zu Körperzellmasse wieder, welches in vielen Studien als Indikator zur frühzeitigen Erfassung einer beginnenden Mangelernährung validiert wurde. Bei der Applikation einer Chemotherapie ist es von großer Bedeutung, dass die vorgesehene Dosis und Dosisintensität der Therapie eingehalten wird. Insbesondere unerwünschte Nebenwirkungen sind häufig für Dosisreduktionen und Verschiebungen der Chemotherapie verantwortlich. In einer prospektiven Studie wurde bei 40 Frauen, die sich aufgrund eines gynäkologischen Malignoms einer Chemotherapie unterzogen haben, die Körperzusammensetzung mit der BIA vor jedem Chemotherapiezyklus gemessen. Diese Studie zeigt, dass durch die Messung der Körperzusammensetzung ein Risikokollektiv, welches für Nebenwirkungen der Therapie anfällig ist, ermittelt werden kann. Der Body Mass Index (BMI) erwies sich als unzureichender Parameter zur Beschreibung des Ernährungszustandes der Patientinnen. Insbesondere muss mit einer erhöhten Rate von Nebenwirkungen der Chemotherapie bei einem verminderten Phasenwinkel, welcher einen reduzierten Ernährungszustand widerspiegelt, gerechnet werden. / In clinical diagnostics the nutritional status is becoming more and more of interest. The nutritional status is closely connected with morbidity and mortality. It is usually evaluated by the body mass index (BMI). An exact estimation of nutritional status can be given by the measurement of body composition. The bioelectrical impedance analysis (BIA) allows a quick and non-invasive measurement of the body composition for each patient. A main point of interest is the phase angle, which is measured directly. It gives a prompt view on the nutritional status. There is a relation between the phase angle and the ECM/BCM-Ratio, a sensitive marker for early signs of malnutrition which was validated in many studies. For patients receiving chemotherapy (CT) it is especially important that the application of the therapy is administered in the right dose and dose intensity. Adverse events often lead to a dose reduction or delay of CT administration. In a prospective clinical study we measured consecutively 40 women receiving chemotherapy for a gynaecological malignancy. BIA was performed before each course of CT. The study demonstrates that an evaluation of the nutritional status can be used to predict the risk for adverse events in patients under chemotherapy. The BMI showed not to be a reliable parameter to estimate the nutritional status. A decreased phase angle which is a parameter for a reduced nutritional status showes that a higher rate of side effects in chemotherapy can be expected .
36

Contribution to numerical and experimental studies of flutter in space turbines : aerodynamic analysis of subsonic and supersonic flows in response to a prescribed vibratory mode of the structure

Ferria, Hakim 01 February 2011 (has links) (PDF)
Modern turbomachines are designed towards thinner, lighter and highly loaded blades. This gives rise to increased sensitivity to flow induced vibrations such as flutter, which leads to structure failure in a short period of time if not sufficiently damped. Although numerical tools are more and more reliable, flutter prediction still depends on a large degree on simplified models. In addition, the critical nature of flutter, resulting in poor welldocumented real cases in the open literature, and the lack of experimental database typical of engine flows make its apprehension even more challenging. In that context, the present thesis is dedicated to study flutter in recent turbines through aerodynamic analysis of subsonic or supersonic flows in response to a prescribed vibratory mode of the structure. The objective is to highlight some mechanisms potentially responsible for flutter in order to be in better position when designing blades. The strategy consists in leading both experimental and numerical investigations. The experimental part is based on a worldwide unique annular turbine sector cascade employed for measuring the aeroelastic response by means of the aerodynamic influence coefficient technique. The cascade comprises seven low pressure gas turbine blades one of which can oscillate in a controlled way as a rigid body. Aeroelastic responses are measured at various mechanical and aerodynamic parameters: pure and combined modeshapes, reduced frequency, Mach number, incidence angle. In addition to turbulence level measurements, the database aims at assessing the influence of these parameters on the aerodynamic damping, at validating the linear combination principle and at providing input for numerical tools. The numerical part is based on unsteady computations linearized in the frequency domain and performed in the traveling wave mode. The focus is put on two industrial space turbines: 2D computations are performed on an integrally bladed disk, also called blisk; its very low viscous material damping results in complex motions with combined modes and extremely high reduced frequency. The blisk operates at low subsonic conditions without strong non-linearities. Although the blades have been predicted aeroelastically stable, an original methodology based on elementary decompositions of the blade motion is presented to identify the destabilizing movements. The results suggest that the so-called classical flutter is surprisingly prone to occur. Moreover, the aerodynamic damping has been found extremely sensitive to the interblade phase angle and cut-on/cut-off conditions.* 3D computations are then performed on a supersonic turbine, which features shockwaves and boundary layer separation. In contrast, the blade motion is of elementary nature, i.e. purely axial. The blades have been predicted aeroelastically unstable for backward traveling waves and stable for forward traveling waves. The low reduced frequencies allow quasi-steady analysis, which still account for flutter mechanisms: the shock wave motion establishes the boundary between stable and unstable configurations.
37

Associação de indicadores da função da membrana celular com o volume de massa tumoral de pacientes com câncer de pulmão não pequenas células. / association of indicators of cell membrane function to the volume of tumor mass in patients wwith lung cancer

Ivany Alves Castanho 30 November 2009 (has links)
O Ângulo de fase (AF), determinado pela bioimpedância (BIA), detecta mudanças em propriedades elétricas dos tecidos se tornando um indicador de prognóstico em diversas doenças crônicas incluindo o câncer de pulmão. Estudos anteriores têm demonstrado associação do AF com a integridade da função da membrana celular. O presente estudo objetivou verificar a possível associação do AF e da razão entre massa extracelular e massa celular corporal (MEC/MCC) com o volume da massa tumoral (VMT) e sobrevida de homens portadores de neoplasia pulmonar do tipo não pequenas células (NPC), comparando este grupo de pacientes com um grupo controle de fumantes ativos sem câncer. Foram avaliados indivíduos do sexo masculino com diagnóstico histopatológico de câncer do pulmão NPC sem tratamento prévio de quimioterapia, radioterapia ou cirurgia (G1=30) e fumantes ativos sem sinais de doença (G2, n=30). A determinação volumétrica da massa tumoral dos pacientes foi através do software Bebúi (Sistema de Análise de Nódulos Pulmonares) e segmentação feita mediante processo semi-automático com o uso de algoritmo de crescimento por região e agregação de voxels. A análise por BIA foi realizada através do aparelho Biodynamics modelo 450. A idade média do G1 foi 65,69,3 anos e G2, 61,58,5 anos. Para a avaliação da capacidade funcional dos pacientes utilizou-se a escala de desempenho Karnofsky Performance Status Scale (KPS). Não houve diferença significativa entre as médias das medidas antropométricas nos dois grupos. No entanto, o AF em média no G1 foi menor em 0,43 (p < 0,05) com a média da razão MEC/MCC maior (1,280,14 p < 0,02) em relação ao G2. Os resultados entre as associações dos indicadores da função celular com o volume de doença foram: AF e VMT (r= - 0,545; p < 0,02);MEC:MCC e o VMT (r= 0,594; p<0,01), AF e KPS (r= 0,44 p= 0,015 ). Foi observada maior sobrevida para os pacientes com o KPS >70% (p < 0,02); AF &#8805; 5,65 (p < 0,04); razão MEC/MCC<1,22 (p< 0,01) e VMT &#8804; 163 ml (p< 0,04). No G2 o AF associou-se com a carga tabágica (r= - 0,54; p < 0,03), apontando possivelmente para as alterações da função celular causadas pela nicotina em fumantes ativos com carga tabágica alta. Nossos resultados, avaliados em conjunto mostram que o AF e a razão MEC/MCC devem ser empregados para avaliar a integridade da função da membrana celular em pacientes com câncer de pulmão NPC no período que antecede o tratamento e que a carga tabágica deve ser considerada como variável importante na avaliação do AF em estudos com indivíduos com ausência de doença. / Phase angle (PA), determined by bioelectrical impedance analysis (BIA), detects changes in electrical properties of the tissues becoming a prognostic indicator in several chronic diseases including lung cancer. This study aimed to verify the possible relationship of AF and the ratio of extracellular mass and body cell mass (ECM/ BCM) with the measure of the volume of the tumor mass and survival of men with lung cancer in non-small cell (NSC), comparing this group of patients with active smokers group control without cancer. We evaluated the males with histopathology diagnosis of lung cancer NSC previously untreated chemotherapy, radiotherapy or surgery (G1 = 30) and active smokers with no signs of disease (G2, n = 30). The volumetric measurement of tumor mass of patients was through software Bebuí (Analysis System of Pulmonary Nodules) and segmentation done by semi-automatic process using a region growing algorithm and aggregation of voxels. The analysis by BIA was performed using the apparatus Biodynamics model 450. The average age of G1 was 65.6 9.3 years and G2, 61.5 8.5 years. For the assessment of functional capacity of patients used the Karnofsky Performance Status Scale (KPS). There was no significant difference between the means of anthropometric measurements in both groups. However, the AF average was lower in G1 at 0.43 (p <0.05) with the mean ratio of ECM / BCM higher (1.28 0.14 p <0.02) compared to G2. The results of the associations between indicators of cellular function with the volume of disease were: PA and VMT (r = - 0.545, p <0.02), MEC/MCC and VMT (r = 0.594, p <0.01), PA and KPS (r = 0.44 p = 0.015). We observed longer survival for patients with KPS> 70% (p <0.02), PA &#8805; 5.65 (p <0.04); reason ECM / BCM <1.22 (p <0.01) VMT and &#8804; 163 ml (p <0.04). PA was associated with the level of smoking (r = - 0.54, p <0.03) in G2, possibly pointing to changes in cellular function caused by nicotine in active smokers with high nicotine load. Our results, evaluated together show that the PA and the reason ECM / MCC should be employed to assess the integrity of the cell membrane in patients with lung cancer NSC in the period before the treatment and that the level of smoking should be considered as variable important in assessing PA in studies with subjects with no disease.
38

Associação de indicadores da função da membrana celular com o volume de massa tumoral de pacientes com câncer de pulmão não pequenas células. / association of indicators of cell membrane function to the volume of tumor mass in patients wwith lung cancer

Ivany Alves Castanho 30 November 2009 (has links)
O Ângulo de fase (AF), determinado pela bioimpedância (BIA), detecta mudanças em propriedades elétricas dos tecidos se tornando um indicador de prognóstico em diversas doenças crônicas incluindo o câncer de pulmão. Estudos anteriores têm demonstrado associação do AF com a integridade da função da membrana celular. O presente estudo objetivou verificar a possível associação do AF e da razão entre massa extracelular e massa celular corporal (MEC/MCC) com o volume da massa tumoral (VMT) e sobrevida de homens portadores de neoplasia pulmonar do tipo não pequenas células (NPC), comparando este grupo de pacientes com um grupo controle de fumantes ativos sem câncer. Foram avaliados indivíduos do sexo masculino com diagnóstico histopatológico de câncer do pulmão NPC sem tratamento prévio de quimioterapia, radioterapia ou cirurgia (G1=30) e fumantes ativos sem sinais de doença (G2, n=30). A determinação volumétrica da massa tumoral dos pacientes foi através do software Bebúi (Sistema de Análise de Nódulos Pulmonares) e segmentação feita mediante processo semi-automático com o uso de algoritmo de crescimento por região e agregação de voxels. A análise por BIA foi realizada através do aparelho Biodynamics modelo 450. A idade média do G1 foi 65,69,3 anos e G2, 61,58,5 anos. Para a avaliação da capacidade funcional dos pacientes utilizou-se a escala de desempenho Karnofsky Performance Status Scale (KPS). Não houve diferença significativa entre as médias das medidas antropométricas nos dois grupos. No entanto, o AF em média no G1 foi menor em 0,43 (p < 0,05) com a média da razão MEC/MCC maior (1,280,14 p < 0,02) em relação ao G2. Os resultados entre as associações dos indicadores da função celular com o volume de doença foram: AF e VMT (r= - 0,545; p < 0,02);MEC:MCC e o VMT (r= 0,594; p<0,01), AF e KPS (r= 0,44 p= 0,015 ). Foi observada maior sobrevida para os pacientes com o KPS >70% (p < 0,02); AF &#8805; 5,65 (p < 0,04); razão MEC/MCC<1,22 (p< 0,01) e VMT &#8804; 163 ml (p< 0,04). No G2 o AF associou-se com a carga tabágica (r= - 0,54; p < 0,03), apontando possivelmente para as alterações da função celular causadas pela nicotina em fumantes ativos com carga tabágica alta. Nossos resultados, avaliados em conjunto mostram que o AF e a razão MEC/MCC devem ser empregados para avaliar a integridade da função da membrana celular em pacientes com câncer de pulmão NPC no período que antecede o tratamento e que a carga tabágica deve ser considerada como variável importante na avaliação do AF em estudos com indivíduos com ausência de doença. / Phase angle (PA), determined by bioelectrical impedance analysis (BIA), detects changes in electrical properties of the tissues becoming a prognostic indicator in several chronic diseases including lung cancer. This study aimed to verify the possible relationship of AF and the ratio of extracellular mass and body cell mass (ECM/ BCM) with the measure of the volume of the tumor mass and survival of men with lung cancer in non-small cell (NSC), comparing this group of patients with active smokers group control without cancer. We evaluated the males with histopathology diagnosis of lung cancer NSC previously untreated chemotherapy, radiotherapy or surgery (G1 = 30) and active smokers with no signs of disease (G2, n = 30). The volumetric measurement of tumor mass of patients was through software Bebuí (Analysis System of Pulmonary Nodules) and segmentation done by semi-automatic process using a region growing algorithm and aggregation of voxels. The analysis by BIA was performed using the apparatus Biodynamics model 450. The average age of G1 was 65.6 9.3 years and G2, 61.5 8.5 years. For the assessment of functional capacity of patients used the Karnofsky Performance Status Scale (KPS). There was no significant difference between the means of anthropometric measurements in both groups. However, the AF average was lower in G1 at 0.43 (p <0.05) with the mean ratio of ECM / BCM higher (1.28 0.14 p <0.02) compared to G2. The results of the associations between indicators of cellular function with the volume of disease were: PA and VMT (r = - 0.545, p <0.02), MEC/MCC and VMT (r = 0.594, p <0.01), PA and KPS (r = 0.44 p = 0.015). We observed longer survival for patients with KPS> 70% (p <0.02), PA &#8805; 5.65 (p <0.04); reason ECM / BCM <1.22 (p <0.01) VMT and &#8804; 163 ml (p <0.04). PA was associated with the level of smoking (r = - 0.54, p <0.03) in G2, possibly pointing to changes in cellular function caused by nicotine in active smokers with high nicotine load. Our results, evaluated together show that the PA and the reason ECM / MCC should be employed to assess the integrity of the cell membrane in patients with lung cancer NSC in the period before the treatment and that the level of smoking should be considered as variable important in assessing PA in studies with subjects with no disease.
39

Parâmetros de avaliação nutricional para detectar desnutrição em pacientes com AIDS em tratamento com antirretrovirais / Nutritional assessment parameter to detect malnutrition in Aids patients on retroviral therapy

Carla Alexandra Almeida Salmazo 11 August 2010 (has links)
A avaliação do estado nutricional em pacientes com HIV é de grande importância, pois as conseqüências provocadas pelo processo patológico da doença estão associadas com perda de peso corporal, massa magra e desnutrição grave, o que prediz aumento da morbimortalidade. Os valores de linfometria CD4 também têm sido utilizados como preditores a curto e médio prazo para o desenvolvimento de infecções oportunistas, as quais são incomuns em pacientes com CD4 >200 cels/mm3. Partindo deste conhecimento, optou-se por estudar o estado nutricional de homens e mulheres HIV positivos de acordo com a contagem de células CD4. Utilizou-se como parâmetros nutricionais o índice de massa corporal (IMC), a área muscular do braço corrigida (AMBc), albumina sérica e o ângulo de fase (AF). Foram estudados 39 pacientes HIV positivos, acompanhados pelo ambulatório de doenças infectoparasitárias do Hospital Universitário Pedro Ernesto (HUPE/UERJ). Não foi observada desnutrição na população estudada, quando avaliada pelo IMC e albumina em ambos os sexos, independente do número de células CD4. Entretanto, a AMBc e o AF, tanto nos homens quanto nas mulheres, demonstraram comprometimento nos parâmetros de massa magra. Em relação à associação entre os indicadores nutricionais e o número de células CD4, foi observado correlação significante com a AMBc e a albumina no grupo estudado. A correlação de acordo com o sexo manteve-se significante em ambos os grupos para AMBc e com uma tendência positiva (p=0,06) entre o AF e CD4 no grupo dos homens. Portanto, estes resultados demonstram que para avaliar o estado nutricional, principalmente o compartimento de massa corporal magra de pacientes HIV positivos sob terapia antirretroviral, é preciso utilizar indicadores mais sensíveis, mesmo naqueles pacientes com melhor estado de controle da doença. / The assessment of nutritional status in patients with HIV is of great importance, because the consequences caused by the pathological process of the disease are associated with weight loss, lean body mass and severe malnutrition, which predicts increased morbidity and mortality. The values of CD4 linfometria have also been used as predictors of short and medium term development of opportunistic infections, which are uncommon in patients with CD4 counts > 200 cells/mm3. Based on this knowledge, we chose to study the nutritional status of HIV positive men and women according to CD4 cell count. Participants had the following nutritional parameters assessed: body mass index (BMI), corrected arm muscle area (AMA), serum albumin and the phase angle (PA). We studied 39 HIV-positive patients, under treatment in a infectious diseases clinic of the University Hospital Pedro Ernesto (HUPE). None of patients has malnutrition according BMI and albumin in both sexes, regardless of the number of CD4 cells. However, in men and women to AMA and the PA, have demonstrated reductions in parameters of lean body mass. Regarding the association between nutritional indicators and the number of CD4 cells, we observed a significant correlation with the AMA and albumin in the study group. The correlation according to gender remained significant in both groups for AMA and a positive trend (p = 0.06) between the PA and CD4 in males. Therefore these results demonstrate that to assess nutritional status, especially the compartiment of lean body mass in HIV positive patients under antirretrovirals, it is necessary to use more sensitive, even in patients with the best state of disease control.
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Vlastnosti nízkoteplotních polymerem modifikovaných asfaltů / Properties of polymer modified bitumen for warm mix asphalt

Zábranský, Ivo January 2019 (has links)
The Diploma thesis is focus on polymer modified bitumen for warm mix asphalt. The theoretical part of the thesis describes additives which influence the properties of bitumen for their use and reduction of production and service temperatures. Further, the theoretical part describes the conclusions from the researches. This part also describes empirical and functional tests of bituminous binders. The practical part presents the results of individual tests. Tests were performed on samples of non-aged, aged by RTFOT and RTFOT + PAV methods. The results of the work and the assessment of the suitability of bituminous binders are summarized at the end of the thesis.

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