A theory is developed to explain the dependence of carrier transport in a thin semiconducting film on film thickness, magnetic field strength, and the dominant bulk scattering mechanism. This theory is based on the solution of the linearized Boltzmann equation in relaxation time form. The semiconductor is assumed to be bounded and nondegenerate with spherical energy surfaces and a scalar effective mass, It is also assumed to be flat banded with totally diffuse scattering at the surface. Classical Boltzmann statistics are used for equilibrium. The dependence of the relaxation time on the carrier energy is approximated by a power law equation. The principle improvement over similar theories is the treatment of the dependence of the relaxation time on carrier energy. The power law approximation for this dependence is valid for randomizing and elastic scattering mechanisms.

Magister Scientiae - MSc / The focus of this study is to synthesize a novel hinged polymer actuator. The linking molecule (hinge) is phenazine with interconnected dipyrrole units. / South Africa

This thesis aims to establish a greater understanding of the effects of the single-sided robotic tufting process on component manufacturing costs and weight, and subsequently determine whether potential economic benefits can be realised through its implementation. To complete this assessment, the study uses the novel composite rib post application of the Next Generation Composite Wing (NGCW) project as an example case, investigating the component’s manufacturing cost, performance and weight relative to those of a non-tufted rib post with the same initial fabric layup, and a prepreg rib post with the same fibre orientation and fibre volume fraction. Detailed analyses of the tufted composite rib post manufacturing process have established the relationships between its manufacturing activities and the consumed resources, facilitating the creation of a novel cost model incorporating algorithms defining the robotic tufting process, which may be adapted for different geometries and tuft parameters. In addition, novel permeability data for the considered tufted preform have been obtained experimentally allowing the simulation of the liquid composite manufacturing process. The insertion of tufting in the studied arrangement was shown to decrease the in-plane permeability of the preform, reducing the characteristic by a factor of 3.5 in the direction perpendicular to the tuft seams, and 1.8 in the direction parallel. Completing structural analyses and further cost modelling, the study considers the manufacturing costs and weight of each of the studied components when performance is normalised. Implementing weight penalties including lifetime fuel consumption and lifetime revenue, appreciation is given to the potential lifetime costs generated by each of the structural solutions. Comparing the amalgamated costs of each component, relative economy has been evaluated both when considering equipment amortisation and also the use of pre-amortised equipment. Considering lifetime fuel cost/kg as the weight penalty, the novel composite rib post has greater economy within the pure pull-off load case without tufting due to its lower manufacturing costs. However, with the consideration of a more significant weight penalty, such as potential increased lifetime revenue, the use of the novel composite rib post results in superior economy, its lifetime cost/part is estimated to be 14% less than the component without tufting and 61% less than the lifetime cost/part of the prepreg component. Critical evaluations of the project’s methodologies have highlighted the various assumptions made due to the limitations of available information and means to perform certain validations. Under these circumstances the assumptions are believed to be the best representations of what is experienced in reality. As far as possible, errors believed to be the result of assumptions have been accounted for in rigorous error analyses to establish their propagation through the various calculations performed. These analyses have provided confidence in the results of the study, ensuring the significance of the determined economical differences between the investigated components.

Since the building construction area is accounted for high share of energy usage (36 %) in Europe, there is high demand to pay attention to this area accurately. Sweden which is one of the pioneer countries in terms of building energy efficiency plans to reduce this value to 50 % by 2050. To reduce this value there is a need to define a mandatory guideline for builders by the government. So national board of housing, building and planning (Boverket) were given responsibility to define these regulations for builders and house owners. Parallel with that Swedish green building council developed a certification considering the buildin g’s energy demand, indoor air climate and environmental impact of building called Miljöbyggnad. While all the existing and new buildings following Boverket’s regulations meet this certification’s lowest limitations, some ambitious builders tend to fulfil its highest level of limitations called Gold level. This study aimed to design a house in the area of Smedjebacken to meet Miljö byggnad’s gold house’s energy category requirements. To meet the mentioned requirements several parametric studies regarding insulation thickness, windows assembly, heating and ventilation system are done via simulation software called TRNSYS. The result of testing several models show that although windows assembly does not affect this building ’s energy demand very much, other parameters such as insulation ’s thickness and type of heating system have a key role. In addition, a parametric study regarding the impact of thermal mass on the building energy demand is performed. The result shows that the effect of removed massive wood is compensated by replaced additional mineral wool insulation. In conclusion it is concluded that a single family house located in a cold climate like Smedjebacken using district heating cannot meet Miljöbyggnad’s gold level criteria without help of heat recovery ventilation. Furthermore, building with ground source heat pump as its heating system can meet Miljöbyggnad’s principals easier than those having district heating. In this case building with 200 mm insulation thickness even with exhaust air ventilation meets certification principals easily.

Ce travail de Thèse est consacré à la caractérisation de la structure thermique des fronts de flammelaminaire de prémélange H2/CH4/Air et H2/CO/Air pauvres. L’étude a été réalisée sur un brûleur à jets opposés, permettant de stabiliser des flammes planes stationnaires, dans des conditions quasi-adiabatiques, pour différentes conditions d’étirement. Un diagnostic de Vélocimétrie par Imagerie de Particule (PIV) et un diagnostic bidimensionnel de diffusion Rayleigh induite par laser ont été utilisés successivement pour étudier l’influence de la richesse, de la concentration en hydrogène dans le combustible et de l’étirement sur le profil de température normal au front de flamme. Trois grandeurs fondamentales ont été étudiées : la température des gaz brûlés, le gradient maximum de température et l’épaisseur de flamme au sens de Spalding. Une attention particulière a été portée à l’interprétation du signal Rayleigh. Ce dernier dépendant notamment de la composition du gaz qui évolue à travers le front de flamme. Dans ce travaille de thèse, cette évolution a été évaluée numériquement (simulations 1D : CANTERA et OPPDIF) puis prise en compte pour améliorer le traitement des données expérimentales. Les résultats expérimentaux couvrent une gamme de richesses s’étalant pour H2/CH4/Air et H2/CO/Air, respectivement de 0.6 à 0.8 et de 0.4 à 0.6. Les concentrations en hydrogène dans le combustible s’étalent respectivement de 0 à 50% et de 10 à 50%. Une comparaison systématique a été faite avec les résultats de simulation numérique 1D (OPPDIF). / This Thesis is devoted to the characterization of the thermal structure of H2/CH4/Air and H2/CO/Air laminar flames. Counterflow flame setup has been used to study planar flames in steady and near-adiabatic conditions. Particle Image Velocimetry and laser induced Rayleigh scattering diagnostics has been successively applied to characterize the influence of equivalent ratio, hydrogen concentration in fuel and stretch on the temperature profile normal to the flame front. Three fundamental characteristics have been studied: the burned gas temperature, the maximum temperature gradient and the flame thickness defined by Spalding. Particular attention has been brought to the interpretation of the Rayleigh signal. Indeed, Rayleigh scattering depends on the gas composition which evolves across the flame front. This evolution has been numerical evaluated in this work (1D simulation: CANTERA and OPPDIF) and taken into account to improve Rayleigh data processing. Experimental results have been obtained for lean flames: equivalent ratio spreads from 0.6 to 0.8 and from 0.4 to 0.6 respectively for H2/CH4/Air and H2/CO/Air flames. A wide range of hydrogen concentration has been studied: from 0 to 50% of hydrogen in fuel for H2/CH4/Air flames and from 10 to 50% of hydrogen in fuel for H2/CO/Air flames. Experimental and numerical (OPPDIF) results have been systematically confronted.

Os stents são dispositivos intravasculares implantados com o objetivo de dilatar ou fixar a placa de colesterol contra a parede arterial. O objetivo avaliar dois tipos de stents de aço inoxidável, um recoberto com poliéster (dacron) e outro não recoberto, implantados na aorta infra-renal de suínos jovens, foram avaliados por morfometria digital para medir o espessamento intimal. Foi realizado um estudo experimental randomizado, separados em dois grupos(stents não revestidos e revestidos com dacron) e duas fases (I e II). Oito stents recobertos com dacron e oito stents de aço inoxidável (30mm de extensão e 8 mm de diâmetro), não revestidos, foram implantados através de abordagem retroperitoneal na aorta infrarenal normal de 16 suínos normolipêmicos. Para a passagem do sistema de implante, foi necessário uma pequena arteriotomia na aorta distal (fase I). Após quatro semanas, a aorta com os stents foram removidas em monoblocos (fase II). Os valores de hematimetria e do lipidograma foram coletados nas duas fases e não apresentaram alterações que pudessem influenciar o estudo. Amostras de tecido dos sítios de fixação (proximal e distal) dos stents foram retiradas, confeccionadas lâminas, que foram coradas pelas técnicas de hematoxilina e eosina de Verhoeff e enviadas para análise morfométrica digital. A camada intima distal não apresentou diferença estatística significativa. A camada média proximal das porções proximal e da porção distal não apresentaram diferença entre os grupos. Os dois tipos de stents apresentaram 100% de perviedade, boa biocompatibilidade e boa incorporação a parede aórtica de suínos normolipêmicos. A camada íntima proximal do grupo de stents revestidos com dacron apresentou espessura maior do que os stents não revestidos, mas com significância estatísitica limítrofe. / Stents are intravascular devices implanted with the objective of dilating or fixing the cholesterol plate against the arterial wall. To evaluate, by digital morphometry, the intimal thickening after the placement of two different kinds of stents: polyester covered stainless steel stents (Dacron) and non-covered stents implanted in young pigs’ infrarenal aortas. The stents were made at the Biotransformation Laboratory of Federal University of Rio Grande do Sul. The experiment was performed at the Biotério of University of Caxias do Sul, carried out on two separate groups of pigs. Eight polyester-covered stainless steel stents (Dacron) and eight stainless steel stents (30-mm long, 8-mm diameter) were deployed through extraperitoneal approach in the normal infrarenal aorta of 16 normolipemic pigs. To allow the passage of the delivery system, a small arteriotomy was performed (phase I). After four weeks, the aorta with the stent was removed en bloc. (phase II). The values of the hematimetric and lipid analysis did not show any changes that could influence the study. Tissue samples of the fixing sites (proximal and distal) of the stents were taken. Microscope slices were prepared and submitted to Verhoeff’s hematoxilin and eosin techniques and sent to morphometric analysis.The intima immediately proximal to the device was thicker in the group of covered stents with marginal significance. The distal intimal layer, proximal medial layer of the proximal portion and distal portion did not present statistical difference between the two groups. Patency was 100% in both groups of these normolipemic pigs. After four weeks the intimal layer immediately proximal to the covered stents was ticker when compared to uncovered stents, but this had a borderline significance. The intimal layer distal to covered stents and the media proximal or distal to the devices had similar morphometric features when covered and uncovered stents where compared.

Modelos geométricos desempenham um papel fundamental em divérsas áreas, desde a indústria do entretenimento até aplicações científicas. Para reduzir o elevado custo de criação de um modelo 3D, a reutilização de modelos existentes é a solução ideal. Recuperação de modelos 3D utilizam técnicas baseadas em conteúdo (do inglês CBR) que auxiliam a busca de modelos desejados em repositórios massivos, muitos disponíveis publicamente na Internet. Pontos principais para técnicas CBR eficientes e eficazes são descritores de forma que capturam com precisão as características de uma forma 3D e são capazes de discriminar entre diferentes formas. Nós apresentamos um descritor com base na distribuição de duas características globais, extraídas de uma forma 3D, depth complexity e thickness, que, respectivamente, capturam aspectos da topologia e da geometria das formas 3D. O descritor final, chamado DCT (depth complexity and thickness histogram), é um histograma 2D invariante a translações, rotações e escalas das formas geométricas. Nós eficientemente implementamos o DCT na GPU, permitindo sua utilização em consultas em tempo real em grandes bases de dados de modelos 3D. Nós validamos o DCT com as Princeton e Toyohashi Forma Benchmarks, contendo 1815 e 10000 modelos respectivamente. Os resultados mostram que DCT pode discriminar classes significativas desses benchmarks, é rápido e robusto contra transformações de forma e diferentes níveis de subdivisão e suavidade dos modelos. / Geometric models play a vital role in several fields, from the entertainment industry to scientific applications. To reduce the high cost of model creation, reusing existing models is the solution of choice. Model reuse is supported by content-based shape retrieval (CBR) techniques that help finding the desired models in massive repositories, many publicly available on the Internet. Key to efficient and effective CBR techniques are shape descriptors that accurately capture the characteristics of a shape and are able to discriminate between different shapes. We present a descriptor based on the distribution of two global features measured on a 3D shape, depth complexity and thickness, which respectively capture aspects of the geometry and topology of 3D shapes. The final descriptor, called DCT (depth complexity and thickness histogram), is a 2D histogram that is invariant to the translation, rotation and scale of geometric shapes. We efficiently implement the DCT on the GPU, allowing its use in real-time queries of large model databases. We validate the DCT with the Princeton and Toyohashi Shape Benchmarks, containing 1815 and 10000 models respectively. Results show that DCT can discriminate meaningful classes of these benchmarks, and is fast to compute and robust against shape transformations and different levels of subdivision and smoothness.

Com o objetivo de caracterizar o crescimento de animais cruza Wagyu x Angus, 24 machos castrados e 23 fêmeas foram separados em: G1M (Grupo 1 Machos, com percentagem de gordura intramuscular inicial > 3,4%, n= 11), G2M (Grupo 2 Machos, com percentagem de gordura intramuscular inicial < 3,4%, n= 13), G1F (Grupo 1 Fêmeas, com percentagem de gordura intramuscular inicial > 3,9%, n= 12) e G2F (Grupo 2 Fêmeas, com percentagem de gordura intramuscular inicial < 3,9%, n= 11) e avaliados com medidas seriadas de ultrassom ajustadas a cada 56 dias. Para estimar as características de carcaça foram utilizados 21 machos castrados, avaliados por ultrassom 3 a 8 dias pré abate e posteriormente na carcaça com 48 horas de resfriamento. O grupo G2M apresentou maior deposição de gordura subcutânea por ultrassom (EGSUS) em seis períodos de avaliação quando comparado ao G1M, apresentando uma taxa de deposição de gordura subcutânea distinta entre grupos de 0.69mm/100 dias e 0.65mm/100 dias para o G2M e G1M, respectivamente. Somente foi possível evidenciar diferença significativa na primeira avaliação de percentagem de gordura intramuscular (PGIMUS) entre G1M e G2M, ambos apresentaram crescimento linear com taxa de aumento de 0.28%/100 dias, foi possível evidenciar que ocorreram aumentos acima de 0.1% da PGIMUS a partir dos 280 dias do período de avaliação, quando o ganho médio diário (GMD) de peso vivo ficou acima de 0.650 kg/dia. A taxa de desenvolvimento da área do músculo longissimus (AOLUS) foi distinta entre os grupos de fêmeas, aumentando 3.8 cm2/100 dias e 3.4 cm2/100 dias para o G1F e G2F, respectivamente. Ocorreram diferenças significativas na PGIMUS somente nas quatro primeiras avaliações entre G1F e G2F. A correlação entre a área do músculo longissimus medida na carcaça (AOLC) e por ultrassom (AOLUS) foi de 0.93, para espessura de gordura subcutânea medida na carcaça (EGSC) e por ultrassom (EGSUS) foi de 0.86. A PGIMUS a desmama não afetou o crescimento do tecido muscular nos machos e adiposo nas fêmeas. As características gordura subcutânea no sítio anatômico da costela nos machos e AOLUS nas fêmeas apresentaram crescimento distinto com relação à PGIMUS a desmama. A ultrassonografia é uma tecnologia que pode ser utilizada para estimar o desenvolvimento tecidual da gordura e músculo com medidas repetidas no tempo. O peso vivo e o GMD afetaram a alteração do tecido muscular e adiposo durante o crescimento. / Aiming to characterize the growth crossbred Wagyu x Angus, 24 steers and 23 heifers were separated in: G1M (Group 1 Males, with initial percentage of intramuscular fat > 3,4%, n= 11), G2M (Group 1 Males, with initial percentage of intramuscular fat < 3,4%, n= 13), G1F (Group 1 Females with initial percentage of intramuscular fat > 3,9%, n= 12) e G2F (Group 2 Females, with initial of intramuscular fat percentage < 3,9%, n= 11) and evaluated with serial ultrasound measurements fitted every 56 days. To estimate carcass traits were used 21 steers, assessed by ultrasound 3 to 8 days pre slaughter and afterwards in the carcass after 48 hours of cooling. The G2M group showed higher deposition of ultrasound subcutaneous fat thickness (UFAT) in six periods of evaluation when compared to G1M, displaying a distinct subcutaneous fat deposition rate between groups of 0.69 mm/100 days and 0.65mm/100 days to G2M and G1M, respectively. Only possible to evidence a significant difference in the first evaluation of the ultrasound percentage of intramuscular fat (UPFAT) between G1M and G2M, both showed linear growth with an increase rate of 0.28%/100 days, it became clear that there were rises above 0.1% of UPFAT from 280 days of the evaluation period, when the average daily gain (ADG) of body weight was above 0.650 kg/day. The development rate of ultrasound longissimus muscle area (ULMA) was different between the groups of females, increasing 3.8 cm2/100 days and 3.4 cm2/100 days to the G1F and G2F, respectively. There were significant differences in the UPFAT in just the first four assessments between G1F and G2F. The corrections between carcass longissimus muscle area (CLMA) wit measured by ultrasound (ULMA) was 0.93 and carcass fat thickness (CFAT) whit fat thickness by ultrasound (UFAT) was 0.86. The UPFAT weaning did not affect the growth of muscle tissue in males and fat in females. Subcutaneous fat in the anatomical site of the rib in males and ULMA in females showed distinct growth compared to the UPFAT weaning. Ultrasonography is a technology that can be used to estimate the development of tissue fat and muscle with repeated measurements over time. The body weight and the ADG affected the change in muscle and adipose tissue during growth.

O objetivo deste estudo foi avaliar a resposta de crescimento e desenvolvimento tecidual de gordura e músculo, através de medidas seriadas obtidas por ultrassom em fêmeas Brangus após desmama, até os 16 meses de idade em diferentes manejos alimentares. O trabalho envolveu 43 fêmeas da raça Brangus. No início do estudo os animais apresentavam uma média de peso vivo (PV) ajustado aos 205 dias de idade de 172.9 ± 18.45 kg e foram distribuídos aleatoriamente em quatro tratamentos de manejo alimentar (MA). O tratamento 1 (T1, n = 9) com média de PV e erro padrão de 160.1 ± 2.5 kg, respectivamente. O tratamento 2 (T2, n = 9) 158.1 ± 4.4 kg, tratamento 3 (T3, n = 9) 167.3 ± 3.8 kg e tratamento 4 (T4, n = 16) 170.8 ± 3.6 kg. As características peso vivo, área do músculo longissimus (AOL) e espessura de gordura subcutânea (EGS) foram mensuradas dos 205 até os 485 dias de idade, enquanto que espessura de gordura na picanha (EGP) foi mensurada dos 261 até os 485 dias de idade. O peso vivo, AOL, EGS e EGP foram avaliados a cada 56 dias. O ganho médio diário (GMD) de PV apresentou uma grande influência no crescimento e na deposição dos tecidos muscular e adiposo, sendo necessários ganhos acima de 0.566 kg/dia, para que possa ocorrer o crescimento destes tecidos. A deposição de gordura de cobertura pode ser comprometida em animais que experimentam ganhos médios diários menores que 0.401 kg/dia na fase de recria, culminando com perda de escore corporal. Nas condições deste estudo, o manejo alimentar T4 mostrou impacto no aumento do peso vivo e deposição tecidual de gordura e músculo aos 16 meses de idade. O manejo alimentar com suplementação energética diária por um período de 112 dias durante o inverno sob condições de pastoreio, afetou positivamente a percentagem do peso vivo maduro aos 16 meses de idade, o crescimento e o desenvolvimento da área do músculo longissimus, espessura de gordura na costela e espessura de gordura na picanha. As magnitudes das taxas de ganho de peso vivo são determinantes na deposição tecidual de gordura e músculo. A ultrassonografia em tempo real é uma tecnologia que pode ser utilizada para estimar o desenvolvimento tecidual da gordura e músculo com medidas repetidas no tempo, para ser utilizada como ferramenta de manejo e método de seleção de novilhas de reposição para obtenção de eficiência no sistema de produção. / The objective of this study was to evaluate the growth and tissue development of fat and muscle through serial measurements obtained by ultrasound in Brangus females after weaning until 16 months of age under different feeding management. The study involved 43 Brangus breed females. At the begin of study the animals had an average body weight (BW) set at 205 days of age of 172.9 ± 18.45 kg and were randomized into four feeding management treatments (MA). Treatment 1 (T1, n = 9) with an average of BW and standard error of 160.1 ± 2.5 kg, respectively. Treatment 2 (T2, n = 9) 158.1 ± 4.4 kg, treatment 3 (T3, n = 9) 167.3 ± 3.8 kg and Treatment 4 (T4 n = 16) 170.8 ± 3.6 kg. The characteristics BW, rib eye area (REA), back fat thickness (BF), were measured from 205 to 485 days of age, while rump fat (RF) was measured from 261 to 485 days age. Body weight, REA, BF and RF were evaluated every 56 days. The average daily gain (ADG) had a strong influence on growth and deposition of muscle and fat tissues, requiring gains above of 0.566 kg/day, to occur growth of these tissues. The deposition of fat cover may be compromised in animals with average daily gain lower than 0.401 kg/day in the growing phase, culminating in loss of body score condition. In our study, feeding management T4 showed impact on the increase of body weight and tissue deposition of fat and muscle to 16 months of age. The feeding regime with daily energy supplementation for a period of 112 days during the winter under grazing conditions, positively affected the percentage of mature body weight at 16 months of age, growth and development of rib eye area, back fat thickness and rump fat. The magnitudes of live weight gain rates are crucial in tissue deposition of fat and muscle. The real-time ultrasound is a technology that can be used to estimate the tissue development of fat and muscle with repeated measures over time, to be used as a management tool and replacement heifer selection method for obtaining efficient production system.

Objetivos: Comparar a espessura muscular e a espessura da gordura subcutânea entre crianças e adolescentes com fibrose cística e sujeitos hígidos utilizando imagens de ultrassonografia. Métodos: Estudo transversal em crianças e adolescentes com diagnóstico de FC, com idade entre 6 e 18 anos, em acompanhamento ambulatorial no Hospital São Lucas da PUCRS e controles hígidos.Os sujeitos que apresentavam exacerbação pulmonar e incapacidade de realizar os procedimentos do estudo foram excluídos. Os participantes submeteram-se a ultrassonografia para verificar a espessura muscular e a espessura da gordura subcutânea das regiões do tríceps, quadríceps e gastrocnêmio, medidas antropométricas e avaliação das dobras cutâneas (adipometria). As estimativas dos componentes da composição corporal foram fracionados em quatro: massa muscular, massa de gordura, massa óssea e residual e foram analisados conforme equações matemáticas e fórmulas específicas previamente validadas. Os indivíduos com FC realizaram a avaliação da função pulmonar por meio da espirometria. A comparação entre os grupos estudados foi realizada através do teste de McNemar, t de Student para amostras pareadas e teste de Wilcoxon. As correlações foram avaliadas através do teste de correlação de Pearson. Resultados: Foram incluídos 84 participantes, sendo 39 com FC e 45 controles, média de idade de 12,94 anos e 61,9 % do sexo masculino. Houve diferença significativa na comparação entre as características demográficas e antropométricas, entre os dois grupos avaliados, para raça (p<0,01), IPAQ (p<0,01) e escore Z do IMC (p<0,03). Na comparação entre os componentes da composição corporal entre os grupos, houve diferença significativa no peso de gordura (p<0,02) e no peso ósseo (p<0,01). Não houve diferenças significativas entre o peso muscular e o peso residual. Houve correlação da ultrassonografia muscular do tríceps e a massa magra (r=0,253; p<0,05) e entre a ultrassonografia muscular do quadríceps com o escore Z do IMC (r=0,25; p<0,05). Não houve correlações significativas na ultrassonografia da gordura subcutânea do tríceps, do quadríceps e do gastrocnêmio entre os grupos avaliados. Ao correlacionar os dois métodos de avaliação de gordura corporal, obtiveram-se correlações significativas (p<0,01) moderadas e positivas, variando de r=0,472 até r=0,681. No grupo dos pacientes com fibrose cística, a espessura muscular do tríceps medida pela ultrassonografia correlacionou-se com o escore Z da caminhada de seis minutos (r=-0,376). Além disso, a espessura muscular do quadríceps medida pela ultrassonografia correlacionou-se com a massa magra (r=0,424; p<0,01), capacidade vital forçada (CVF) (r=0,468; p<0,01), percentual do previsto da CVF (r=0,338; p<0,05), escore Z da CVF (r=0,336; p<0,05) e com o volume expiratório forçado no primeiro segundo (VEF1) (r=0,393; p<0,05). Conclusão: A avaliação da espessura muscular de pacientes com FC por ultrassonografia foi semelhante aos indivíduos controles, da mesma maneira que a avaliação da massa magra obtida com a adipometria e medidas de perímetros. Na avaliação da espessura de gordura subcutânea, houve correlação moderada entre a adipometria e a ultrassonografia. A ultrassonografiaapresenta potencial de aplicabilidade para diagnóstico nutricionaledeveser melhor avaliada, a fim de validara sua utilização emavaliações de rotina. / Objectives: To compare muscle and subcutaneous fat thickness between children and adolescents with cystic fibrosis and healthy subjects using ultrasound images. Methods: Cross-sectional study in children and adolescents diagnosed with CF, aged 6 to 18 years, followed at Hospital São Lucas PUCRS, and healthy controls (HC). Subjects who had a pulmonary exacerbation or inability to perform the study procedures were excluded. The participants underwent ultrasound to check muscle and subcutaneous fat thickness at the triceps, quadriceps and gastronomies regions, anthropometric measurements and evaluation of skin folds. Component estimation of body composition were divided into four: muscle mass, fat mass, bone and residual mass and were analyzed according to mathematical equations and previously validated specific equations. CF individual sunder went pulmonary function assessment by spirometry. Comparison between groups was performed using Mc Nemar test, Student's t test for paired samples and Wilcoxon test. Correlations were assessed using Pearson's correlation test. Results: We included 84 participants, 39 with CF and 45 healthy controls, mean age was 12.94 years and 61.9% were male. There was a significant difference between demographic and anthropometric characteristics between the two groups, for race (p<0.01) IPAQ (p<0.01) and BMI Z score (p<0.03). Comparing the components of body composition between the groups there was no significant difference in fat weight (p<0.02) and bone weight (p<0.01). There were no significant differences between muscle weight and the residual weight. There was a correlation of ultrasound triceps muscle and lean body mass (r=0.253; p<0.05) and between the quadriceps muscle ultrasound with the Z score of BMI (r=0.25; p<0.05). There were no significant correlations in ultrasound subcutaneous fat triceps, quadriceps and gastronomies between the groups. By correlating the two methods of assessing body fat, significant correlations (p<0.01) and moderate positive, ranging from r=0.472 to r= 0.681were found. In CF patients, muscular thickness of the triceps measured by ultrasonography correlated with walk test six minutes Z score (r= -0.376). Furthermore, quadriceps muscle thickness measured by ultrasonography correlated with body lean mass (r=0.424; p<0.01), forced vital capacity (FVC) (r=0.468; P<0.01) percentage of predicted FVC (r = 0.338; p <0.05), FVC Z score (r= 0.336; p<0.05) and forced expiratory volume in one second (FEV1) (r=0.393; p<0.05). Conclusion: Evaluation of muscle thickness in CF patients and HC by ultrasound rendered similar results in the same fashion as the assessment of lean body mass by skin fold and circumference measurements. In assessing subcutaneous fat thickness, there was moderate correlation between skin folds and ultrasound findings. Ultrasound evaluation shows an applicability potentiality for nutritional diagnosis and should be better evaluated in order to validate its use in routine clinical assessments.