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Thermofluidic Transport in Evaporating Droplets: Measurement and ApplicationAditya Chandramohan (6635972) 14 May 2019 (has links)
<p>Microscale
environments provide significant resolution and distortion challenges with
respect to measurement techniques; however, with improvements to existing
techniques, it is possible to gather relevant data to better understand the
thermal and fluidic mechanisms at such small scales in evaporating droplets.</p>
<p> </p>
<p>Infrared
thermography provides several unique challenges at small scales. A primary issue is that the low native
resolution of traditional infrared cameras significantly hamper the collection
of details of microscale features.
Furthermore, surfaces exhibiting vastly different emissivities, results
in inaccurate temperature measurements that can only be corrected with
irradiance-based emissivity maps of the surface; however, due to the resolution
limitations of infrared thermography, these emissivity maps can also display
significant errors. These issues are
overcome through the use of multi-frame super-resolution. The enhanced resolution allows for better
capture of microscale features, therefore, enhancing the emissivity map. A quantitative error analysis of the system
is conducted to quantify the feature size resolution improvement as well as the
smoothing effect of super-resolution reconstruction. Furthermore, a sensitivity analysis is
conducted to quantify the impact of registration uncertainty on the accuracy of
the reconstruction. Finally, the improved emissivity map from super-resolution
is demonstrated to show the increased accuracy over low-resolution mapping.</p>
<p> </p>
<p>When
applied to water droplets, particularly on nonwetting surfaces, infrared
thermography is confounded by the presence of nonuniform reflectivities due to
the spherical curvature of the liquid-air interface. Thus, when measuring the temperature along
the vertical axis of a water droplet, it is necessary to correct the
reflection. Using a controlled
background environment, in conjunction with the Fresnel equations, it is
possible to correct the reflective effects on the interface and calculate the
actual temperature profile. This allows
for a better understanding of the governing mechanisms that determine the
thermal transport within the droplet.
While thermal conduction is the primary transport mechanism along the
vertical axis of the droplet, it is determined that the temperature drop is
partially dampened by the convective transport from the ambient air to the
liquid interface. From this
understanding revealed by the measurements, the vapor-diffusion-based model for
evaporation was enhanced to better predict evaporation rates.</p>
<p> </p>
<p>Further
exploration into the mechanisms behind droplet evaporation on nonwetting
surfaces requires accurate knowledge of the internal flow behavior. In addition, the influence of the working
fluid can have a significant impact on the governing mechanisms driving the flow
and the magnitude of the flowrate. While
water droplet evaporation has been shown to be governed by buoyancy-driven
convection on nonwetting substrates, similar studies on organic liquid droplets
are lacking. Particle image velocimetry
is effective at generating a velocity flow field, but droplets introduce
distortion due to the refraction from the spherical interface of the
droplet. As such, velocity correction using
a ray-tracing approach was conducted to correct the velocity magnitudes and
direction. With the velocity
measurements, the flow was determined to be surface-tension-driven and showed speeds
that are an order of magnitude higher than those seen in buoyancy-driven flow
in water droplets. This resulted in the
discovery that advection plays a significant role in the transport within the
droplet. As such, the vapor-diffusion-governed
evaporation model was adjusted to show a dramatic improvement at predicting the
temperature gradient along the vertical axis of the droplet.</p>
<p> </p>
<p>Armed
with the knowledge of flow behavior inside droplets, it is expected that
droplets with aqueous solutions should exhibit buoyancy-driven convection. The final part of this work, therefore,
leverages this phenomenon to enhance mixing during reactions. Colorimetry is a technique that is widely
utilized to measure the concentration of a desired sample within some liquid;
the sample reacts with a reagent dye the color change is measured, usually
through absorbance measurements. In
particular, the Bradford assay is used to measure protein concentration by
reacting the protein to a Coomassie<sup>TM</sup> Brilliant Blue G-250. The absorbance of the dye increases, most
significantly at the 590 nm wavelength, allowing for precise quantitation
of the amount of protein in the solution.
A droplet-based reaction chamber with buoyancy-enhanced mixing has the
potential to speed up the measurement process by removing the need for a
separate pre-mixing step. Furthermore,
the reduced volume makes the process more efficient in terms of reactant
usage. Experimental results of premixed
solutions of protein sample and reagent dye show that the absorbance measurement
through a droplet tracks strongly with the protein concentration. When the protein sample and dye reagent are mixed
<i>in situ</i>, the complex interaction
between the reactants, the mixing, and the adsorption of protein onto the
substrate creates a unique temporal evolution in the measured absorbance of the
droplet. The characteristic peaks and valleys of this evolution track strongly
with concentration and provide the framework for measurement of concentration
in a droplet-based system.</p>
<p> </p>
<p>This thesis extends knowledge about droplet
thermal and fluidic behavior through enhanced measurement techniques. This knowledge is then leveraged in a novel
application to create a simple, buoyancy-driven colorimetric reaction setup. Overall, this study contributes to the field
of miniaturized, efficient reaction and measurement devices.</p>
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Investigation into high-speed thermal instability testing of synchronous turbo-generator rotorsNarain Singh, Amesh January 2017 (has links)
A thesis submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy.
Johannesburg, 2017 / The research presented in this thesis conclusively shows that the most effective method to perform synchronous turbo-generator rotor Thermal Instability Testing is by utilising the current injection method of condition assessment. Analysis of the experiences of a local utility for well over a decade has uncovered a high number of rotors failing thermal instability testing in recent years. This trend has brought the current testing methodology into question. Two different assessment modes of testing have been found to be utilised internationally without preference, namely, current injection and friction/windage. By determining the method that is best suited to detect a thermally sensitive rotor a service provider can benefit by improved rotor reliability as well as cost saving. The evaluation is accomplished by utilising a scaled down experimental setup based on the model of a local testing facility as well as a 600 MW turbo-generator rotor. A direct thermal mapping technique has been devised utilising infrared thermography to capture the thermal distribution of the rotor surface under different test conditions. The results obtained have shown that the methods differ substantially with the friction method exhibiting a uniform surface distribution and the current-injection method exhibiting areas of higher temperature concentration around the rotor pole faces. However, weaknesses do exist in present-day testing techniques in the form of inaccurate temperature measurements during testing as well as little consideration given to external factors such as the interaction between the slip-ring and brush-gear that have the potential to influence test outcomes. A presented augmented method of performing thermal sensitivity testing taking advantage of infrared thermography is found to improve testing accuracy and aid in fault detection and location. Current thermal instability testing coupled with the direct thermal mapping method has been demonstrated to be the most effective means for performing rotor thermal sensitivity testing. / MT2018
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Analyse énergétique du comportement thermomécanique du PA6.6 chargé de fibres de verre / Energy analysis of the thermomechanical behavior of PA6.6 reinforced with short glass fibres.Benaarbia, Adil 30 October 2014 (has links)
Cette étude présente une analyse thermomécanique du comportement en fatigue oligocyclique du polyamide 6.6 vierge et renforcé de fibres de verre courtes. Des bilans d'énergie sont réalisés en utilisant, de façon combinée, des techniques d'imagerie quantitative visible et infrarouge. Les champs de température sont obtenus par thermographie et les champs de déformation par corrélation d'images. Sur un cycle de chargement, on montre comment il est possible d'estimer séparément les sources de chaleurs moyennes par cycle, sources associées aux mécanismes dissipatifs et induites par les effets de couplage thermomécanique. On montre ensuite, pour différentes fréquences de chargement, l'évolution du bilan de puissance moyen par cycle sur une zone matérielle correspondant à la partie utile de l'éprouvette. Ce bilan prend en compte le taux de l'énergie de déformation, les chaleurs mises en jeu et les variations d'énergie interne. On observe que la forme du bilan de puissance est très fortement dépendante, pour un rapport de charge donné, à la fréquence de sollicitation, à la teneur en eau, à l'orientation des fibres de verre mais aussi aux niveaux de contrainte appliqués. / This study presents a thermomechanical analysis of fatigue behavior of pure and short glass- fiber reinforced polyamide 6.6. The energy balances are drew up using the combined application of visible and infrared quantitative imaging techniques. Temperature fields are obtained by thermography and strain fields by image correlation. Over one complete cycle, we show how it is possible to separately estimate the heat sources averaged over the cycle, associated with dissipative mechanisms and induced by thermomechanical coupling source effets. Then we show, for different loading rates, the time courses of the energy rate balance for a physical area corresponding to the gage part of the specimen. This balance takes into account the deformation energy rate, the heat sources and the internal energy variations. It is observed that the shape of the energy rate balance is highly dependent, for a given load ratio, to the load rate, the water content, the orientation of the glass fibers and the applied stress levels.
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Inspeção termográfica de danos por impacto em laminados compósitos sólidos de matriz polimérica reforçada com fibras de carbono. / Thermographic inspection of impact damage in solid fiber-reinforced polymer matrix composite laminates.Almeida, Euripedes Guilherme Raphael de 30 April 2010 (has links)
Laminados compósitos com matrizes poliméricas, respectivamente termorrígida e termoplástica, reforçadas com fibras contínuas de carbono foram submetidos a impacto único transversal com diferentes níveis de energia. Os danos imprimidos aos materiais estruturais foram avaliados por termografia ativa infravermelha na modalidade transmissão. Em geral, os termogramas do laminado termoplástico apresentaram indicações mais claras e bem definidas dos danos causados por impacto, se comparados aos do compósito termorrígido. O aquecimento convectivo das amostras por fluxo controlado de ar se mostrou mais eficaz que o realizado por irradiação, empregando-se lâmpadas incadecentes. Observou-se também que tempos mais longos de aquecimento favoreceram a visualização dos danos. O posicionamento da face impactada do espécime, relativamente à câmera infravermelha e à fonte de calor, não afetou a qualidade dos termogramas no caso do laminado termorrígido, enquanto que influenciou significativamente os termogramas do compósito termoplástico. Os resultados permitiram concluir que a termografia infravermelha é um método de ensaio não-destrutivo simples, robusto e confiável para a detecção de danos por impacto inferior à 5 Joules em laminados compósitos poliméricos reforçados com fibras de carbono. / Continuous carbon fiber-reinforced thermosetting and thermoplastic composite laminates were exposed to single transversal impact with different energy levels. The damages marked to the structural materials were evaluated by active infrared thermography in transmission mode. In general, the thermoplastic laminate thermograms showed more clear and delineated damage indications when compared to the ones from thermosetting composite. The convective heating of the samples by controlled hot air flow was more efficient than via irradiation using lamp. It was also observed that longer heating times improved the damage visualization. The positioning of the specimen´s impacted face regarding the infrared camera and the heating source did not affect the thermo-imaging of thermosetting specimens, whereas it substantially influenced the thermograms of thermoplastic laminates. The results allow concluding that infrared thermography is a simple, robust and trustworthy methodology for detecting impact damages as light as 5 Joules in carbon fiber composite laminates.
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Tratamento da degeneração testicular em carneiros com suplementação de vitamina A ou laserterapia de baixa intensidade / Treatment of testicular degeneration in rams supplemented with vitamin A or low level laser therapyAlves, Maíra Bianchi Rodrigues 30 May 2014 (has links)
A degeneração testicular (DT) possui grande relevância dentre os distúrbios da reprodução e pode ser causada pelo aumento da temperatura testicular. Este provoca aumento do metabolismo celular, levando ao estresse oxidativo (EO) e apoptose. O tratamento usual consiste na retirada do agente causador e administração de antioxidantes; entretanto, pode não ser eficiente. Dessa forma, o presente estudo preconizou o tratamento da DT por meio de agentes com poder proliferativo: vitamina A e laserterapia de baixa intensidade (LTBI). Foram realizados três experimentos; o experimento 1 objetivou definir a dose de energia da LTBI necessária para a bioestimulação testicular. Foram utilizados seis carneiros distribuídos em três grupos: GC) insulação escrotal (IE) e sem tratamento (n=2); G28) IE e tratado com LTBI com 808 nm de comprimento de onda, 30 mW de potência e 28 J/cm² de densidade de energia por 15 dias a cada 48 horas (n=2); G56) IE e tratado com LTBI com 808 nm, 30 mW e 56 J/cm² por 15 dias a cada 48 horas (n=2). Foram feitas análises clínicas, reprodutivas e histopatológicas. Os dados foram submetidos à análise de variância (ANOVA) e teste de Tukey. Apesar da LTBI diminuir as taxas de espermatozoides com membrana acrossomal íntegra, esta foi eficiente em aumentar a população celular dos túbulos seminíferos no G28. Portanto, a LBTI provocou efeito bioestimulatório em testículos degenerados de carneiros. O experimento 2 objetivou validar a técnica de avaliação do EO espermático por meio da sonda fluorescente CellROX Deep Red®. Foram realizados dois experimentos; o primeiro utilizou ejaculados de três carneiros tratados em T0 (ejaculado não submetido à indução de EO), T50 (50% não induzido e 50% induzido ao EO) e T100 (submetido ao EO). Os dados foram submetidos à regressão linear. No segundo experimento foram utilizados 16 carneiros submetidos à IE. Foram feitas avaliações do EO antes e após a IE. Os dados foram submetidos à ANOVA e teste LSD de Fisher. O coeficiente de determinação foi de 0,728 e houve aumento do EO após a IE. Assim, a sonda CellROX® foi capaz de detectar o EO espermático. No experimento 3 foi proposto tratamento para a DT baseado na suplementação vitamínica ou LTBI. Foram utilizados 33 carneiros distribuídos em seis grupos: CC) sem IE e sem tratamento (n=5); CA) sem IE e tratado com vitamina A IM 120.000 UI/animal, duas vezes por semana durante três semanas (n=6); CL) sem IE e tratado com LTBI protocolo G28 (experimento 1) (n=5); IC) IE e sem tratamento (n = 5); IA) IE e tratado com vitamina A IM 120.000 UI/animal, duas vezes por semana durante três semanas (n=6); IL) IE e tratado com LTBI protocolo G28 (n=6). Foram realizadas análises clínicas, reprodutivas, hormonais e histopatológicas. Os dados foram analisados usando o procedimento de modelos mistos e os efeitos dos tratamentos foram avaliados utilizando contrastes ortogonais. Não houve efeito benéfico dos tratamentos para as características ultrassonográficas, qualidade espermática, concentração de testosterona e aspectos histopatológicos. Assim, os tratamentos não foram eficientes para melhorar a qualidade espermática nem promover a proliferação celular. / The testicular degeneration (TD) has great significance among the reproductive disorders and one of the main causes is the increase in testicular temperature. High testicular temperature results in increase cellular metabolism, leading to oxidative stress and apoptosis. The treatment consists in removing the causative agent and administration of antioxidants; however, it could be not efficient. The objective of this study is to recommend the treatment of TD by administering agents with proliferative action: vitamin A and low level laser therapy (LLLT). For this, three experiments were conducted. In experiment 1 the objective was to define the dose of energy for LLLT testicular biostimulation; it was used six rams distributed in three groups: GC) scrotal insulation (SI) and untreated (n=2); G28) SI and treated with LLLT with 808 nm, 30 mW and 28 J/cm ² of power density for 15 days every 48 hours (n=2); G56) SI and treated with LLLT with 808 nm, 30 mW and 56 J/cm² for 15 days every 48 hours (n=2). Clinics, reproductive and histopathological analyzes were done. Data were subjected to analysis of variance and Tukey test. The rates of sperm with intact acrosome membrane were decreased by LLLT, but the LLLT was effective in increasing the cell population of the seminiferous tubules in the G28. Thus, LLLT was able of causing stimulatory effect in degenerate testis of rams. The objective of experiment 2 was to assess the technique of evaluation of sperm oxidative stress (OS). This study was divided in two experiments; in experiment 1 was used ejaculates of three rams treated in T0 (ejaculate that was not submitted to OS induction), T50 (50% without OS and 50% inducted to OS) and T100 (entire submitted to OS induction). Data obtained were evaluated by linear regression analysis. In experiment 2, sixteen rams were submitted to SI. Analyses of OS were done before and after the SI. Data obtained were evaluated by analysis of variance and Fisher\'s LSD test. The determination coefficient was of 0.728 and there were increase in sperm showing OS after SI period. Thus, CellROX® fluorescent probe was able to detect sperm OS. The objective of experiment 3 was establish a treatment for TD based on vitamin A supplementation or LLLT; 33 rams were distributed in six groups: CC) no SI and non-treated (n=5); CA) no SI and treated with 120,000 IU/animal of IM vitamin A, twice a week for three weeks (n=6); CL) no SI and treated with LLLT G28 protocol (experiment 1) (n=5); IC) SI and untreated (n=5); IA) SI and treated with 120,000 IU/animal of IM vitamin A, twice a week for three weeks (n=6); IL) SI and treated with LLLT G28 protocol (n=6). Clinics, reproductive, hormonal and histopathological analyzes were performed. Data were analyzed using the mixed models procedure and treatments effects were evaluated using orthogonal contrasts. There was no beneficial effect of treatments for ultrasonographic characteristics, sperm quality, testosterone concentration and histopathological aspects. Thus, the treatments were not effective for improving sperm quality or promoting cell proliferation.
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Degeneração testicular em touros: alterações espermáticas e sua relação com a termodinâmica e hemodinâmica testicular / Testicular degeneration: sperm alterations and their relationship with testicular thermodynamics and hemodynamicsGonzaga, Vitor Hugo Guilger 06 October 2017 (has links)
O estresse térmico em touros é um fator muito importante, pois afeta negativamente o comportamento reprodutivo e diminui a eficiência reprodutiva. Uma das causas deste efeito adverso é a ineficiência da termorregulação testicular, que conduz ao aumento do metabolismo celular, causando estresse oxidativo e apoptose das células germinativas, o que caracteriza a degeneração testicular, que pode levar à infertilidade, ou mesmo à esterilidade do animal. A degeneração testicular pode ser diagnosticada pela palpação do órgão, aferição do perímetro escrotal e pelo espermograma. No entanto, outras ferramentas podem ser empregadas para auxiliar no diagnóstico desta alteração, entre elas estão a termografia e a ultrassonografia. Desta forma, neste trabalho avaliou-se a eficiência do termógrafo e do ultrassom como instrumentos auxiliares para o diagnóstico da degeneração testicular em bovinos. Para o presente estudo utilizaram-se 16 touros da raça Nelore separados em dois grupos experimentais: Controle: animais sem indução à degeneração testicular (CON, n = 08); e Degeneração: animais induzidos à degeneração testicular (INS, n = 08) por meio de bolsas insuladoras mantidas por 96 horas. Os animais foram submetidos semanalmente a avaliações das características clínicas e seminais, realizando-se as análises duas semanas antes da insulação testicular (S-2 e S-1), no dia da retirada da bolsa (D0) e durante quatro semanas após a retirada da mesma (S+1 a S+4). Foram avaliadas frequência cardíaca (FC), frequência respiratória (FR) e temperatura retal (TR); avaliações testiculares: perímetro escrotal (PE), consistência testicular (CT), temperatura média da superfície escrotal (TMSE), ecotextura (ETT), ecogenicidade (EGT) e vascularização do parênquima testicular (EVT), vascularização (EVP) e índice de resistência vascular (RIP) do plexo pampiniforme. O sêmen dos touros foi colhido e avaliado considerando motilidade (MT), vigor (VG), morfologia (defeitos maiores, menores e totais), integridade das membranas plasmática e acrossomal e potencial de membrana mitocondrial (PIAIA). Para a análise estatística foi utilizado o Statistical Analysis Software (SAS 9.3). Os dados das avaliações realizadas em S-2 e S-1 foram submetidos ao procedimento MIXED considerando dois grupos (CON e INS). Os dados das avaliações realizadas após a insulação foram submetidos ao procedimento MIXED e adicionando o fator tempo por meio do comando REPEATED. O nível de significância considerado foi de P≤0,05, sendo considerada tendência quando este ficou entre 0,051 e 0,1. Foram realizadas correlações de Pearson, utilizando-se o programa StatView (SAS, 1999). Os grupos de touros foram semelhantes nas semanas pré-insulação. Nas semanas pós-insulação, notou-se interação entre tempo e tratamento para FR (p=0,04), CT (p=0,0003) e RIP (p=0,03) e tendência para EVT (p=0,08). Foram observados maiores valores para TMSE, ETT e EVT para INS do que para CON, mas menores valores de PE, CT, EVP e RIP para INS do que para CON. Além disso, encontrou-se interação entre tempo e tratamento para MT (p=0,01), defeitos morfológicos (p<0,001) e alto potencial mitocondrial (AP, p=0,01) e tendência para PIAIA (p=0,07). O grupo INS apresentou queda na MT, PIAIA e AP, associado com aumento nos defeitos morfológicos. Foram verificadas correlações entre as características ambientais (temperatura ambiente e umidade relativa do ar) e os termogramas. Os termogramas apresentaram correlações com parâmetros vitais e achados testiculares. A hemodinâmica apresentou correlações mais fracas com outras características testiculares. Concluiu-se que o estresse térmico testicular provoca um quadro de degeneração testicular, caracterizado por redução na CT e na MT, PIAIA, PI e AP, além de aumento de defeitos morfológicos espermáticos. Este quadro é acompanhado pelo aumento da TMSE somente no dia da retirada das bolsas, provoca heterogeneidade do parênquima testicular, aumenta a vascularização testicular, reduz a vascularização do plexo pampiniforme e o RI dos vasos do plexo pampiniforme. Desta forma, a termografia e a ultrassonografia testiculares contribuem para o diagnóstico da degeneração testicular em touros. / Heat stress in bulls is a very important factor because it adversely affects the reproductive behavior and reduces the reproductive efficiency. One of the causes of this adverse effect is the inefficiency of testicular thermoregulation, which leads to increased cellular metabolism, causing oxidative stress and apoptosis of germ cells, which characterizes testicular degeneration, which can lead to infertility or even to animal sterility. Testicular degeneration can be diagnosed by palpation of the testicles, scrotal perimeter and sperm analyses. However, other tools can be used to aid in the diagnosis of this alteration, such as thermography and ultrasonography. Thus, this study evaluated the effectiveness of thermography and ultrasound as auxiliary tools in the diagnosis of testicular degeneration in cattle. For the present study, 16 Nelore bulls were divided in two experimental groups: Control: animals without induction to testicular degeneration (CON, n = 08); and Degeneration: animals induced to testicular degeneration (INS, n = 08) through insulation bags, maintained for 96 hours. Animals underwent weekly evaluations of clinical and seminal characteristics, performed assessments two weeks prior to testicular insulation (S-2 and S-1), on the day of the removal of the bag (D0) and during four week after removal of the bag (S+1 to S+4). The following were evaluated: heart rate (HR), respiratory rate (RR) and rectal temperature (RT); testicular evaluations: scrotal circumference (SC), testicular consistency (TC), mean temperature of the scrotal surface (MTSS), echotexture (ETT), echogenicity (EGT), vascularization of testicular parenchyma (VTP), vascularization of the pampiniform plexus (VPP) and resistance index (RI). The semen of the bulls was collected and evaluated considering motility (MT), vigor (VG), morphology (major, minor and total defects), plasma and acrosomal membrane integrity and mitochondrial membrane potential (PIAIA). Statistical analysis was performed using Statistical Analysis Software (SAS 9.3). Data from the S-2 and S-1 evaluations were submitted to the MIXED procedure considering two groups (CON and INS). Data from the evaluations performed after the insulation were submitted to the MIXED procedure adding the time factor through the REPEATED command. The significance level considered was P≤0,05, being considered a trend when it was between 0,051 and 0,1. Pearson correlations were performed using the StatView program (SAS, 1999). The groups were similar in the pre-insulation period. In the post-insulation weeks, it was noted the interaction between time and treatment for RR (p = 0.04), TC (p = 0.0003) and RI (p = 0.03) and a tendency to VTP (p = 0, 08). Greater values were observed for MTSS, ETT and VTP for INS than for CON, but lower values of SC, TC, VPP and RI for INS than for CON. In addition, there was interaction between time and treatment for MT (p = 0.01), morphological defects (p <0.001) and high mitochondrial potential (HMP, p = 0.01) and tendency for PIAIA (p = 0, 07). The INS group presented decrease in MT, PIAIA and HMP, associated with increase in morphological defects. Correlations were found between the environmental characteristics (temperature and relative humidity) and thermograms. The thermograms presented correlations with vital parameters and testicular findings. Hemodynamics showed weaker correlations with other testicular characteristics. In conclusion, testicular heat stress causes a testicular degeneration, characterized by reduction in TC and MT, PIAIA, PI and HMP, in addition to an increase in spermatic morphological defects. This situation, accompanied by the increase in MTSS only on the day of the removal of the bags, causes testicular parenchyma heterogeneity, increases testicular vascularization, reduces pampiniform plexus vascularization and RI of pampiniform plexus vessels. Thus, testicular thermography and ultrasonography contribute to the diagnosis of testicular degeneration in bulls.
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Avaliação termográfica para a detecção de lesões cutâneas clinicamente semelhantes / Thermographic evaluation for the detection of clinically similar cutaneous lesionsAzevedo, Mirian Denise Stringasci de 02 August 2017 (has links)
Dentre os diferentes tipos, o câncer de pele é o tipo de câncer com maior incidência no mundo. É crescente o interesse em explorar técnicas que auxiliem no diagnóstico de lesões malignas e pré-malignas, assim como no monitoramento da eficácia dos tratamentos existentes. As lesões tumorais apresentam temperatura diferente se comparadas a tecidos normais e, com o desenvolvimento de detectores térmicos cada vez mais sensíveis e com melhor qualidade de resolução, a termografia tem se apresentado como uma abordagem de interesse cada vez maior. Os objetivos deste estudo foram: (1) avaliar o uso do imageamento termográfico para o monitoramento e diferenciação de lesões clinicamente semelhantes e (2) analisar a eficiência da terapia fotodinâmica durante o tratamento. Um monitoramento piloto por termografia do crescimento de tumores de Ehrlich (hipotérmicos) injetados no dorso de camundongos Swiss mostrou capacidade para a detecção de tumores a partir de 4 mm de diâmetro. Na avaliação de lesões clínicas, foi investigada a discriminação de pares de lesões cutâneas potencialmente semelhantes clinicamente: CBC versus nevo intradérmico, carcinoma espinocelular (CEC) versus queratose actínica (QA) e queratose seborreica (QSP) versus melanoma. As lesões de CEC foram discriminadas com maior facilidade, apresentando aumento da temperatura na área da lesão em comparação com a região adjacente, enquanto as outras lesões clinicamente identificadas como QA, que podem evoluir para CEC, quase não se diferenciam termicamente do tecido saudável circundante. Uma rotina de processamento das imagens das lesões utilizando um classificador de rede neural mostrou capacidade de diferenciar as lesões dos tipos CBC versus nevo em 67,2% dos casos; em 80% para as lesões de CEC versus QA, e em 50% para as lesões QSP versus melanoma. O monitoramento da terapia fotodinâmica (TFD) foi realizado em lesões clínicas de CBC tratadas em duas sessões. Verificou-se que a região da lesão fica mais evidente termicamente ao longo do procedimento, e as definições das bordas da lesão tornam-se mais delimitadas após o término da iluminação. Com a obtenção das imagens térmicas de TFD criou-se um modelo simplificado para estimar a energia convertida nos processos de transferência de energia envolvidos na TFD. Mesmo com as aproximações realizadas, mostrou-se que a maior parte da energia depositada foi convertida em ação fotodinâmica (53,8%), seguida da parcela que foi dissipada pela perfusão do sangue (37,2%), mostrando que a maior parte da energia depositada no tecido durante o procedimento é incorporada ao efeito fotodinâmico. Esta é uma evidencia de que a ação fotodinâmica não apresenta componente térmica relevante, aspecto importante para o estudo de seus mecanismos. / Among the different cancer types, skin cancer is the most prevalent type of cancer in the world. In most cases, the survival rates are higher when the diagnosis occurs in the early stages of the disease. Thus, there is a growing interest in techniques that aid in the diagnosis of malignant and premalignant lesions, as well as in monitoring the efficacy of existing treatments. Concerning tumor diagnosis, tumor lesions present different temperature compared to normal tissues. Thermography has been presented as an approach of increasing interest due to the development of thermal detectors with better resolution quality and increased sensitivity. The objective of this study was therefore to evaluate the possibility of differentiating clinically similar lesions and monitoring the efficiency of photodynamic therapy during the treatment by using thermographic images and neural network classifiers. A monitoring of the growth of Ehrlich (hypothermic) tumors injected into the Swiss mouse back using thermography showed the technique is able to detect tumors from 4 mm in diameter. For the evaluation of clinical lesions, the discrimination of potentially clinically similar cutaneous lesions: BCC versus intradermal nevus, squamous cell carcinoma (SCC) versus actinic keratosis (AK) and seborrheic keratosis (PSK) versus melanoma were investigated. SCC lesions were more easily discriminated, showing an increase of temperature in the lesion area compared to the adjacent region, while the lesions that were clinically identified as AK (which can possible progress towards SCC lesions) can hardly be thermally differentiated differ thermally from the surrounding healthy tissue. This is a very relevant result, given the great difficulty in diagnosing SCC lesions by the standard dermatoscopy technique. An images processing routine using a neural network classifier showed the ability to differentiate lesions between BCC and nevus types in 67.2% of the cases; 80% for SCC versus AK lesions, and 50% for PSK lesions versus melanoma. The monitoring of photodynamic therapy (PDT) was performed in BCC lesions treated in two sessions. The lesion region becomes more thermally evident throughout the procedure, and the definitions of the lesion edges become more clearly delimited visually after the end of the illumination. By obtaining the thermal images of PDT a model was created to calculate the amount of light energy converted to heat, damage, and other energy transfer processes involved in the PDT. Despite the approximations made, it was shown that most of the deposited energy was converted into photodynamic action (53.8%), followed by the portion cleared from the irradiated tissue by the blood perfusion (37.2%), showing that most of the energy deposited in the tissue during the procedure is incorporated into the photodynamic effect. This is an evidence that the photodynamic action does not present a relevant thermal component, an important aspect for the study of its mechanisms.
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Efeitos da climatização ambiental no comportamento e bem-estar de matrizes e leitões em maternidades livres de gaiolas / Effects of environmental climatization on the behavior and welfare of sows and piglets in cage-free maternityRicci, Gisele Dela 19 October 2018 (has links)
Suínos se adaptam às adversidades ambientais impostas pelo confinamento à partir de alterações fisiológicas e comportamentais e a inserção de climatizações simples podem melhorar o conforto e o bem-estar dos animais. O objetivo deste estudo foi avaliar os efeitos da climatização ambiental da maternidade livre de gaiolas, no comportamento e bem-estar de matrizes e leitões. Foram utilizadas 26 fêmeas e 281 leitões da linhagem Large White x Landrace, desmamados aos 21 dias, mantidos em dois tipos de ambiente: climatizado (ventilador e aspersor em telhado) e não climatizado (controle), no setor de suinocultura da Prefeitura do campus Fernando Costa, da USP, em Pirassununga. A temperatura interna no ambiente controle às 7 horas foi de 23,7°C±0,64 com umidade de 74% ±1,64 e às 13 horas de 26,2°C± 1,23 com umidade de 70,4%± 1,68. No ambiente climatizado, às 7 horas a temperatura ambiental encontrada foi de 22,1°C±0,66C com umidade de 81,9%±1,66 e às 13 horas 24,5°C±0,85 e umidade de 85,7%±1,34. A frequência respiratória e a temperatura retal foram obtidas três vezes por semana, duas vezes ao dia, de manhã e à tarde, por contagem do flanco por minuto e termômetro retal digital, respectivamente. As colheitas de saliva para análise de cortisol (apenas matrizes) foram realizadas uma vez por semana, duas vezes ao dia, de manhã e à tarde. A avaliação da hierarquia de dominância e os registros da escolha das tetas foram realizados em três análises por semana a partir de observações focais diretas, sendo duas por período, de manhã e à tarde. A classificação em leitões dominantes, intermediários e subordinados foi obtida por porca, de acordo com a apresentação de brigas entre leitões. Para análise estatística da hierarquia foi construída uma matriz binária de dominância baseada nas ocorrências das brigas, identificando os indivíduos das linhas que dominam indivíduos das colunas, analisados por meio de variância com efeitos fixos de tratamento, períodos, sexo e suas interações. O comportamento e a preferência ambiental foram obtidos três vezes por semana, duas vezes ao dia, duas horas por período, de manhã e à tarde. Os locais avaliados foram esquerdo (lado com bebedouros), direito (barra antiesmagamento), meio (cama e enriquecimento), frente (piso de concreto) e atrás (cama de bagaço de cana). As medidas de comportamento e preferência ambiental foram avaliadas por análise de variância, com efeitos de tratamento, hora e local. As temperaturas superficiais dorsais, ventrais, das patas, pernis, cabeças, focinhos, oculares e de glândula mamária (porcas) foram medidas utilizando câmera termográfica de infravermelho, além das temperaturas do telhado, da cama e do piso. A temperatura do ar, umidade relativa e a temperatura do globo negro também foram obtidas e armazenadas em datalogger e foram realizadas correlações entre os dados ambientais e de temperatura superficial. As imagens termográficas foram analisadas pelo software IRSoft Version 3.6 Testo e analisadas por variância com efeitos fixos de tratamento e estação do ano. Os resultados mostraram que em relação à hierarquia não houve efeito dos fatores fixos (P>0,05). Os leitões procuraram com maior frequência as tetas intermediárias, superiores e inferiores. O sexo não influenciou na classificação de hierarquia. Leitões classificados como leves apresentaram menor ganho de peso ao desmame no ambiente climatizado. Em relação ao comportamento, não houve interação entre os períodos e os locais para as porcas e leitões. As fêmeas preferiram o lado esquerdo, seguido pelo direito, na frente, atrás e no meio da baia. O peso ao desmame e a perda de peso das fêmeas não apresentaram efeito dos ambientes (P>0,05). Em relação às análises de termografia de infravermelho, as estações do ano influenciaram as temperaturas da cama, do concreto e telhado, devido as maiores temperaturas encontradas no verão. Foram encontradas correlações positivas em relação a temperatura interna das instalações para cama (r=0,28; P<0,05) e concreto (r=0,26; P<0,05). Para as fêmeas, as estações do ano influenciaram as temperaturas corporais. Foram encontradas correlações positivas em relação a cama e as temperaturas do dorso, ventre, glândula mamária, pernil, cabeça e olhos. A frequência respiratória apresentou correlação positiva com o dorso, focinho, cama, concreto e telhado. O cortisol salivar não apresentou correlações positivas e significativa com as instalações. As estações do ano e os períodos do dia influenciaram as temperaturas superficiais dos leitões, com maiores temperaturas no verão e no período da tarde. A frequência respiratória teve influência do período do dia com maiores frequências apresentadas à tarde. Conclui-se com este estudo que a climatização não influencia na escolha das tetas na glândula mamária. A climatização ambiental gerou maior conforto térmico às matrizes, no entanto, não alterou o conforto de leitões, uma vez que estes possuíam escamoteadores com a função de proteger contra temperaturas abaixo da sua zona de conforto térmico. A presença de ventiladores e aspersores de água no telhado não foi suficiente para reduzir a temperatura superficial corporal de fêmeas e leitões inseridos em baias livres de gaiolas em fase de maternidade. / Pigs adapt to the environmental adversities imposed by confinement from physiological and behavioral changes and the insertion of simple climatizations can improve the comfort and well-being of the animals. The objective of this study was to evaluate the effects of environmental conditioning of cage-free motherhood on the behavior and well-being of sows and piglets. Twenty-six females and 281 piglets of the Large White x Landrace strain, weaned at 21 days, were kept in two types of environment: climated (ventilator and sprinkler on roof) and non-climated (control) Costa, of the USP, in Pirassununga. The internal temperature in the control environment at 7 hours was 23.7 ° C ± 0.64 with humidity of 74% ± 1.64 and at 13 hours of 26.2 ° C ± 1.23 with humidity of 70.4% ± 1.68. In the air-conditioned environment, at 7 o\'clock the ambient temperature was 22.1 ° C ± 0.66C with humidity of 81.9% ± 1.66 and at 13 hours 24.5 ° C ± 0.85 and humidity of 85 , 7% ± 1.34. Respiratory rate and rectal temperature were obtained three times a week, twice a day, morning and afternoon, by counting the flank per minute and digital rectal thermometer, respectively. Saliva harvests for cortisol analysis (matrices only) were performed once a week, twice daily in the morning and afternoon. The evaluation of dominance hierarchy and teat selection records were performed in three analyzes per week from direct focal observations, two per period, morning and afternoon. Classification in dominant, intermediate and subordinate piglets was obtained by sow, according to the presentation of fights among piglets. For statistical analysis of the hierarchy, a binary matrix of dominance based on occurrences of fights was constructed, identifying the individuals of the lines dominating column individuals, analyzed by means of variance with fixed treatment effects, periods, sex and their interactions. Behavior and environmental preference were obtained three times per week, twice a day, two hours per period, morning and afternoon. The sites evaluated were left (side with drinking fountains), right (anti-crushing bar), middle (bed and enrichment), front (concrete floor) and behind (cane bagasse bed). The measures of behavior and environmental preference were evaluated by analysis of variance, with effects of treatment, time and place. Dorsal, ventral surface temperatures of the legs, legs, heads, muzzles, eyepieces and mammary gland (sows) were measured using infrared thermographic camera, as well as roof, bed and floor temperatures. The air temperature, relative humidity and black globe temperature were also obtained and stored in a datalogger and correlations were made between environmental and surface temperature data. The thermographic images were analyzed by the software IRSoft Version 3.6 Testo and analyzed by variance with fixed effects of treatment and season of the year. The results showed that in relation to the hierarchy there was no effect of the fixed factors (P> 0.05). The piglets sought more often the intermediate, upper and lower teats. Sex did not influence the classification of hierarchy. Piglets classified as lightweight presented lower weight gain at weaning in the air-conditioned environment. Regarding the behavior, there was no interaction between periods and sites for sows and piglets. The females preferred the left side, followed by the right, front, back and middle of the bay. Weaning weight and weight loss of the females had no effect of the environments (P> 0.05). Regarding infrared thermography analyzes, the seasons of the year influenced bed, concrete and roof temperatures due to the higher summer temperatures. Positive correlations were found regarding the internal temperature of bed facilities (r = 0.28, P <0.05) and concrete (r = 0.26, P <0.05). For females, the seasons influenced the body temperatures. Positive correlations were found regarding bed and temperatures of the back, belly, mammary gland, thigh, head and eyes. The respiratory rate showed a positive correlation with the back, snout, bed, concrete and roof. Salivary cortisol did not present positive and significant correlations with the facilities. The seasons and the periods of the day influenced the superficial temperatures of the piglets, with higher temperatures in the summer and in the afternoon. The respiratory rate was influenced by the period of the day with higher frequencies presented in the afternoon. It is concluded with this study that the climatization does not influence the choice of the tits in the mammary gland. The ambient climated generated greater thermal comfort to the matrices, however, did not alter the comfort of piglets, since they had escamoteadores with the function of protecting against temperatures below their zone of thermal comfort. The presence of ventilators and water sprinklers on the roof was not sufficient to reduce the body surface temperature of females and piglets inserted in stalls free of maternity cages.
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Inclusão de compósitos cimentícios em blocos estruturais cerâmicos com foco em conforto térmicoCarvalho, Milene January 2017 (has links)
Materiais aplicados na construção civil são importantes para fornecer segurança e conforto às pessoas. Quanto mais adequadas as propriedades térmicas, menos energia é necessária para aquecer ou resfriar uma área construída. A NBR 15575:2013 - Desempenho de Edificações Habitacionais, padronizou desempenhos térmicos para construções. Os blocos estruturais cerâmicos atendem o padrão mínimo, porém acredita-se que seu desempenho possa ser melhorado utilizando materiais de características isolantes dentro de seus furos verticais. Assim, o objetivo deste trabalho é investigar compósitos de matriz cimentícia com agregados leves para o aprimoramento térmico de blocos estruturais cerâmicos. Para o estudo, quatro corpos de prova foram produzidos preenchendo o vazado dos blocos com compósitos de matriz cimentícia utilizando 80% agregados leves (argila expandida, vermiculita, poliestireno expandido (EPS) e perlita expandida), 20% de cimento, além de uma amostra preenchida com graute estrutural que é comumente utilizado em edificações de alvenaria estrutural. Também foram produzidos corpos de prova com os compósitos, para a análise de massa específica, microscopia, resistência à compressão, absorção de água e desempenho térmico medido por termografia. Nos blocos, analisou-se massa final preenchido, absorção de água e desempenho térmico. No estudo termográfico, os blocos preenchidos foram comparados ao bloco cerâmico vazado padrão. Concluiu-se que o preenchimento dos vazados dos blocos com todos os compósitos leves e com o graute estrutural proporcionou um desempenho térmico melhor que o do bloco padrão, se destacando o EPS como melhor desempenho. O desempenho térmico dos prismas de compósitos confirmou o que foi observado nos corpos de prova de blocos. Assim foram feitos novos corpos de prova maximizando o teor de EPS para 85% e 90%. A análise térmica destas amostras apresentou melhor resultado para EPS 90%. O aumento do teor de EPS diminuiu a resistência à compressão e aumentou a absorção de água, porém, como o foco é o desempenho térmico e o bloco preenchido com o compósito EPS (90%) atende as características normativas, esta pode ser uma solução interessante. / Materials applied in civil construction are important to provide security and comfort to people. The more appropriate the thermal properties are, the less energy it is necessary to provide heat or cold to a constructed area. The NBR 15575:2013 standard, which deals with the Performance of Residential Constructions, has standardized thermal performances for buildings. Structural ceramic blocks meet the minimum standard, but it is believed that their performance can be improved by means of materials with isolating characteristics within their vertical holes. Thus, the aim of this paper is to investigate cementitious matrix composites with lightweight aggregates for thermal improvement of ceramic structural blocks. For the study, four specimens were produced by filling the hollow spaces of the blocks with cementitious matrix composites using 80% of lightweight aggregates (expanded clay, vermiculite, expanded polystyrene – EPS –, and expanded perlite), and 20% of cement. These were compared to a sample filled with structural grout, which is commonly used in structural masonry buildings. Specimens were also produced with the composites for specific mass analysis, microscopy, compression resistance, water absorption and thermal performance measured by thermography. In the blocks, the final, filled weight was analyzed, as well as water absorption and thermal performance. In the thermographic study, the filled blocks were compared to standard ceramic hollow blocks. It was concluded that filling the hollow spaces of the blocks with all the lightweight composites and structural grout provided a better thermal performance than that of standard blocks, highlighting EPS as having the best performance. Thermal performance of the composite prisms confirms what was observed in the block specimens. Thus, new specimens were made maximizing the EPS content to 85% and 90%. Thermal analysis of these samples presented better results for EPS 90%. The increase in the EPS content decreased compression resistance and increased water absorption. However, as the focus is thermal performance and as the block filled with EPS composite (90%) meets the requirements of the standard, this may be an interesting solution.
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Dor muscular e temperatura muscular: estudo termográfico longitudinal / Muscle Pain and Muscle Temperature : A longitudinal thermographic studyWeber, Marcelo 14 July 2016 (has links)
Embora as causas de DTM tenham sido muito estudadas e discutidas na literatura atual, a associação entre a dor muscular e sua temperatura não está totalmente clara. Para esta investigação, 40 pacientes com dor muscular foram encaminhados da clínica odontológica e foram examinados. Um total de 31 pacientes foram diagnosticados com dor miofascial no musculo masseter pelo RDC e foram incluídos neste estudo. O musculo masseter no lado com dor foi anestesiado e foi comparado ao lado oposto ao longo do tempo. Na análise estatística de comparação, foi encontrada associação entre o aumento de temperatura e a diminuição da dor relatada. Possíveis fatores de confusão, como tempo da dor crônica, idade, índice de massa corpórea, pontos de incapacidade, ICD, pior dor sentida nos últimos meses e dor media nos últimos meses foram levados em consideração e foram estatisticamente analisados e o único fator que mostrou estatisticamente correlação com a diminuição da dor foi o fator tempo. Conclusão: existe uma correlação negativa entre o aumento de temperatura e a diminuição da dor. / Although, TMD causes have been widely studied in the last years, the association between muscle pain and temperature remains unclear. For this investigation, 40 muscle pain patients were referred from dental clinic and were examined. A total of 31 patients were diagnosed with masseter myofascial pain by RDC criteria and were included in this study. Masseter muscle was blocked in the pain side and was compared among the time to opposite side. In the matching statistics association analysis, it was found association between temperature increase and related pain decrease. Possible confounders (time of chronic pain, age, Body Mass Index, ICD, incapacity points, worst pain in the last six months, average pain in last six month) were took in consideration and only time since the pain started seems to be related to decrease in pain. Conclusion: there is a negative association between muscle pain and muscle temperature.
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