Spelling suggestions: "subject:"breath"" "subject:"wreath""
61 |
Desenvolvimento de um aparato para a coleta do condensado do exalado pulmonar visando a análise do óxido nítrico em indivíduos hígidos / Development of an apparatus for the collection of Exhaled Breath Condensate in order to analysis of Nitric Oxide in healthy subjectsDaniella Alves Vento 02 September 2011 (has links)
O óxido nítrico (NO) tem papel relevante nas diversas funções fisiológicas do organismo e nos mais variados sistemas que o compõe. Sabe-se que esta molécula é um constituinte normal do ar exalado na respiração de humanos e de animais. Tem como funções modular respostas inflamatórias e imunes bem como atuar na regulação do tônus vascular da musculatura lisa das vias aéreas. Esta molécula vem sendo reconhecida como importante marcador de lesão pulmonar, o que despertou a intensa investigação do NO no ar exalado. Uma metodologia não invasiva, de baixo custo e de fácil aplicação está sendo extensivamente estudada para a captação do ar exalado através do seu resfriamento e condensação, denominada Condensado do Exalado Pulmonar (CEP). É grande o interesse no estudo de doenças pulmonares inflamatórias, no entanto, observa-se uma considerável carência de evidências acerca dos níveis de concentração de mediadores inflamatórios, como o NO em amostras de indivíduos hígidos utilizando o CEP. Diante disso, decidiu-se elaborar um protótipo de aparato para coleta do condensado e empregar esta técnica para determinar valores de concentração de NO em uma amostra de voluntários hígidos. A metodologia de coleta utilizada foi baseada nas recomendações da força tarefa da American Thoracic Society/European Respiratory Society (ATS/ERS) para procedimentos de coleta de condensado, com o intuito de evitar erros metodológicos, padronizar e trazer mais evidências para auxiliar a inserção do método na rotina clínica, além de disponibilizá-lo para novas pesquisas. Para isto foram selecionados 116 indivíduos adultos hígidos de ambos os sexos, com idade entre 20 e 70 anos. O protótipo de aparato utilizado na pesquisa foi de fabricação artesanal e desenvolvido na Divisão de Cirurgia Torácica e Cardiovascular da Faculdade de Medicina da Universidade de São Paulo- FMRP/USP, visto que os aparatos comerciais são todos importados, de custo elevado e que ainda não forneceram evidências suficientes de que algum destes seria o padrão ouro para a coleta. O aparato foi eficiente para coletar o CEP e o NO foi detectável em todas as amostras. A média de NO foi de 13±14,4µM, e não houve correlação com o gênero (p=0,847) e idade (p=0,811). Não foi observado correlação entre o NO e o volume de CEP coletado (p=0,944). O volume de CEP coletado é dependente do volume exalado total (p<0,001). A partir destes resultados pode-se verificar que o aparato é viável e eficiente. Não foram encontradas correlações entre a concentração de NO no CEP, idade e o gênero. O presente estudo poderá contribuir com futuras pesquisas de caráter comparativo e fornecer mais uma opção de aparato para coleta do condensado do exalado pulmonar, provendo baixo custo, reprodutibilidade e reutilização do aparato / Nitric oxide (NO) plays an important role in various physiological functions in the body and in various systems that compose it. It is known that this molecule is a normal constituent of exhaled breath in humans and animals. Its functions modulate inflammatory and immune responses as well as act in the regulation of vascular tone of smooth muscles of the airways. This molecule has been recognized as an important marker of lung injury, which sparked intense investigation of exhaled NO. A non-invasive method, low cost and easy application has been extensively studied to collect the exhaled air through its cooling and condensation, termed exhaled breath condensate. There is great interest in the study of inflammatory lung diseases, however, there is a considerable lack of evidence about the concentration levels of inflammatory mediators such NO in samples of healthy individuals using exhaled breath condensate. Given this, it was decided to develop a prototype apparatus for collecting exhaled breath condensate (EBC) and employ this technique to determine concentration values of nitric oxide in a sample of healthy volunteers. The sampling methodology based on the recommendations of the task force of the American Thoracic Society / European Respiratory Society (ATS / ERS) for procedures using for collection of condensate, in order to avoid methodological errors, standardize and bring more evidence to support the inclusion of the method in clinical routine, and make it available for further research. We selected 116 healthy adults of both gender, aged between 20 and 70. The prototype apparatus used in the research was designed, produced and developed in the Division of Thoracic and Cardiovascular Surgery, Faculty of Medicine, University of São Paulo-FMRP / USP. The commercial devices are all imported, expensive and not yet provided sufficient evidence that any of these would be the gold standard for collection. The apparatus was efficient to collect the EBC and NO was detectable in all samplesThe average NO was 14.4 ± 13 µM, and there was no correlation with gender (p = 0.847) and age (p = 0.811). There was no correlation between NO and the volume of collected EBC (p = 0.944). The volume of collected EBC is dependent on the total exhaled volume (p <0.001). From these results it can be seen that the apparatus is feasible and efficient. No correlation was found between the concentration of NO in the EBC, age and gender. The present study may contribute to future comparative studies of character and provide another option for apparatus for collecting condensate, providing low cost, reliability and reusability of the apparatus
|
62 |
The lungs remember breathCotton, Aliyah 04 January 2021 (has links)
Please note: creative writing theses are permanently embargoed in OpenBU. No public access is forecasted for these. To request private access, please click on the lock icon and filled out the appropriate web form. / 2999-01-01T00:00:00Z
|
63 |
Towards optimizing particle deposition in bifurcating structuresSonnenberg, Adam 19 May 2020 (has links)
Particle deposition patterns formed in the lung upon inhalation are of interest to a wide spectrum of biomedical sciences, particularly for their influence on non-invasive therapies which deliver drugs to the respiratory track. Before reaching the alveoli, particles, or a collection of liquid droplets called aerosols, must transverse this bifurcating network. This dissertation proposes a multi-faceted strategy for optimizing current methods of drug delivery by analyzing particle deposition in a single bifurcation and a complex 3-dimensional tree as a model of the airways. In this thesis, previous probabilistic formulations of particle deposition in a single bifurcation were first examined, combined and verified by computational fluid dynamic modeling. The traditional single bifurcation model was then extended to a multigenerational network as a Markov chain. The probabilistic approach combined with detailed fluid mechanics in bifurcating structures, permits a more realistic treatment of particle deposition. The formulation enables a rapid comparative analysis among different flow policies, i.e. how varying modes of inhalation affect local particle deposition and total particle escape rates. For example, this approach showed that body position has a minimal effect on deposition pattern, while a specific flow profile maximize deposition into the periphery of the lung.
Also included are novel experimental results of particle deposition. Most experimental deposition studies are restricted to total deposition. Regional deposition can only be estimated but not directly measured without the destruction of the lung like models. As a result, the measurement requires multiple models which adds to the variance. To this end a standard physical model for investigating effects of various ventilation strategies on regional particle deposition was developed. Results suggest that a brief pause in flow can increase deposition into regions of blocked airways where drugs would not otherwise enter. Experiments were also conducted to investigate the effects of inertia dominated flow in symmetric and asymmetric structures revealing novel features in 3D compared to 2D.
This dissertation combines experimental and computation results to propose a strategy to efficiently move particles through a symmetric and asymmetric bifurcating structure. It also introduces possible strategies for maximizing deposition to a desired region of a lung structure.
|
64 |
Possible interference by common odoriferous foodstuffs in the determination of breath-alcohol content using the Intoxilyzer 4011ASJones, Gail Eileen 01 January 1988 (has links) (PDF)
However, interferences by inhaled volatile compounds are not the aim of the present study. The objective of this report is to determine if common food stuffs would cause an interference with the CMI Intoxilyzer. It has been theorized that if one has been eating while drinking alcoholic beverages, the food might cause an elevated breath-alcohol test result. Odorous foods were chosen on the theory that if it could be smelled on one's breath, it would perhaps elicit a reading on the instrument. The list of foods was further narrowed to those commonly found in eating and drinking establishments (i.e. pizza shops) or those foods taken in an attempt to conceal the presence of ethanol in the breath (i.e. mints and candies).
|
65 |
Creating an Individualized Predictive Model of PAO2 and PACO2 Changes During Voluntary Static Apnea for Sedentary Subjects / Att skapa en individualiserad prediktiv modell av PAO2- och PACO2-förändringar under frivillig statisk apné för stillasittande personerAnthony, Diana January 2018 (has links)
The primary aim of this study was to fill a gap in the literature in understanding maximal BH in untrained, non-divers by generating a predictive numerical model for PAO2 and PACO2 throughout BH. There have been little to no previous attempts at explicitly characterizing the influence of impermanent personal or environmental factors on PAO2 or PACO2 at BH breakpoint. The metabolic human consumption of O2 and production of CO2 as measured through alveolar partial pressures was observed over time during a voluntary maximum breath-hold for 18 members of the general population. The coefficient of determination was used to determine accuracy of the model in fitting participants’ BH data from this experiment. The volume of the last inhalation pre-BH, time to subjective breakpoint, and breath-to-breath calculated respiratory exchange ratio (RER) were identified as the most influential combination of key variables that improved PAO2 model fit (from R2 = 0.8591 to R2 = 0.8840). Clustering methods coupled with two sample t-tests or ANOVA were then used to identify survey responses most correlated to inter-BH similarities. These were barometric pressure, age, height, weight, resting HR, smoker/ freediver/scuba experience, and weekly frequency of engaging in physical exercise. The model was validated on testing data from an experienced free-diver, from non-rebreathing trials of a sample of the participants, and from simulated dives of 5 participants from research in the Environmental Physiology Department of Karolinska in 1994 [1]. It has been suggested that the presented model can be a valuable tool in developing safer free diving practices. Furthermore, interesting trends in continuous HR, starting PACO2 values, and O2 consumption were observed and analyzed using statistical analysis. Findings were discussed with connection to the underlying physiological principles that might explain the results obtained.
|
66 |
Chemosensory Evaluation of Training and Oxidative Stress in Long Distance RunnersWhysong, Christan Yvonne 28 May 2014 (has links)
Athletes complete a balance of training loads and rest periods, risking overtraining when this balance favors excessive training. Diagnostic biomarkers have been suggested but a clear diagnostic method is not available. This preliminary study's objective was to use data standardization to improve an electronic nose's (enose) discrimination model for athletes' breathprints after cumulative and acute training loads.
Collegiate long distance runners were observed throughout competitive training seasons. Prolonged training effects were observed through Profile of Mood States (POMS) surveys and blood and breath samples collected at the beginning (Pre-Study) and end of the training season (Post-Study). Immediate training effects were observed for one low (LI) and one high (HI) intensity acute training load. Subjects provided blood and breath samples before the LI (BSR) and HI (BLR), completed the training load, and provided blood and breath samples after each training load (ASR; ALR). Blood was analyzed for antioxidant enzymes (catalase, glutathione peroxidase, and glutathione reductase). Breath samples were analyzed with a Cyranose® 320 (C320) enose.
Age, gender, and training loads affected oxidative states, with the HI having more effect than the LI. Mood profiles indicated healthy and successful athletes. Neither POMS nor blood parameters suggested overtrained athletes.
The C320 successfully discriminated between breathprints of athletes correlating to the training loads. Direct data standardization through carbon dioxide as a baseline sensor purge correctly classified 100 percent of the data through linear discriminant analysis (LDA). Indirect data standardization by subtracting Pre-Study data from the subsequent data classes (e.g. BSR) correctly classified 96 percent of the data.
An LDA on the combined blood parameters correctly classified 61.9 percent of the data. The blood analyses required invasive sample collections and involved procedures that took a long time (hours). In comparison, the best C320 model correctly classified 96 percent of the data and required less invasive sample collections, simple analysis, and short result times (minutes).
Evidence suggested the C320 will provide a simple and noninvasive method for clinically diagnosing the onset of overtraining. The unit is small, handheld, rapid, and noninvasive so it could also be used on- site to provide immediate feedback for training optimization. / Ph. D.
|
67 |
Deodorization of Garlic Breath Volatiles by Food and Food ComponentsMunch, Ryan Nicholas January 2013 (has links)
No description available.
|
68 |
Development of a breath monitoring system using an STM32 microcontroller and a Bluetooth device with connected MEMS-based sensorsRavichandran, Vijayakanna January 2024 (has links)
No description available.
|
69 |
Propriedades físico-químicas de sistemas compostos por materiais celulósicos e aditivos funcionais / Physicochemical properties of systems composed of cellulosic materials and functional additivesBlachechen, Leandro Schafranski 29 October 2014 (has links)
O presente estudo demonstrou que a formação de cavidades (breath figures) em filmes de CA, CAPh, CAB e CMCAB preparados por spin-coating de soluções em tetrahidrofurano (THF) foi dependente das características moleculares dos polímeros quando preparados em ambiente com umidade relativa baixa (UR 35%), enquanto que em UR mais elevadas (55% e 75%) o balanço entre a energia superficial da água, THF e energia interfacial entre água e THF foi determinante. Por outro lado, a rápida exposição (de 3 a 6 min) desses filmes ao vapor de solvente teve um efeito plastificante tornando os filmes de CAB, CAPh e CMCAB completamente lisos, enquanto que para filmes de CA foi observado o efeito dewetting. Surfactantes biocompatíveis à base de sorbitano (Tween®) foram usados como plastificantes para filmes de ésteres de celulose obtidos por evaporação de solvente. O comportamento térmico dos filmes foi dependente do tamanho da cauda hidrofóbica do surfactante, do tipo do grupo lateral dos polímeros e da composição da mistura. Tween 20 e 40 mostraram agir como um excelente plastificante para os ésteres de celulose, exceto para o CA, no qual foi imiscível. Teores baixos de Tween favoreceram a flexibilidade das cadeias de polímeros ao passo que quantidades maiores aumentaram a mobilidade molecular dos ésteres de celulose levando a variações de Tg de até 200 °C. Filmes de nanocompósitos de CAB reforçados com nanocristais de celulose (CNC) modificados com diferentes grupos funcionais (acetato e metiladipoíla) foram preparados a partir de dispersões em acetato de etila (AE), THF e N,N-dimetilformamida (DMF). A melhor estabilidade coloidal foi verificada em DMF, devido sua alta polaridade. Suspensões em AE e THF de CNC modificados foram mais estáveis do que CNC por conta das interações entre grupos substituintes e solventes. As propriedades mecânicas dos nanocompósitos, resultantes da dispersibilidade de nanocristais na matriz de CAB mostraram forte relação com a estabilidade coloidal das dispersões. Beads de celulose foram obtidos utilizando polpa pré-tratada de eucalipto, oxidados e utilizados como suporte para incorporação de um agente bactericida QPVP-C5. Bactérias de Micrococcus luteus adsorveram sobre beads oxidados e nos beads contendo baixa quantidade de QPVP-C5 adsorvido e foi observada propriedade biocida nos beads com elevada quantidade de QPVP-C5 adsorvido. Os resultados mostram o preparo de materiais celulósicos multifuncionais de baixo custo e simples preparação para aplicações em meios aquosos com a finalidade de imobilização e ação biocida frente a bactérias Gram-positivas. / The present study demonstrated that the breath figures formation in CA, CAPh, CAB and CMCAB films spin-coated from solutions in tetrahydrofuran (THF) was dependent on the polymers molecular characteristics when prepared under low relative humidity (RH 35%), whereas under higher RH (55% and 75%), the balance among water and THF surface energy and interfacial energy between water and THF was determinant. On the other hand, the short solvent vapor exposure had a plasticizer effect, making CAB, CAPh and CMCAB films completely smooth (from 3 up to 6 min), while dewetting phenomena was observed for CA films. Biocompatible sorbitan-based surfactants (Tween®) were used as plasticizer for CA, CAPh, CAB and CMCAB casted films. The thermal behavior of films was dependent on the size of surfactant hydrophobic tail, type of polymer side group and the mixture composition. Tween 20 and 40 showed act as an excellent plasticizer for cellulose esters, except for CA, which was immiscible. Low Tween content favored polymeric chains flexibility while higher content increased the cellulose esters molecular mobility leading to Tg variations up to 200 °C. CAB-based nanocomposites casted films reinforced with cellulose nanocrystals (CNC) modified with different functional groups (acetate and methyl adipoil) were prepared from dispersions in ethyl acetate (EA), THF and N,N-dimethylformamide (DMF). The best colloidal stability was verified in DMF, due its high polarity. Suspensions in EA and THF of modified CNC where more stable than unmodified CNC, regarding the interactions among substituents groups and solvents. The mechanical properties of nanocomposites stemming from nanocrystals dispersibility in the CAB matrix showed strong relationship with the colloidal stability. Cellulose beads were obtained by using pretreated Eucalyptus pulp, oxidized and used as a support for the incorporation of a biocide agent. Micrococcus luteus bacteria adsorbed onto oxidized beads and on the beads with low content of adsorbed QPVP-C5. It was observed biocide property for the beads with high QPVP-C5 content. The results show the simple preparation of low cost multifunctional cellulosic materials for applications in aqueous media for the purpose of immobilization and biocide action against Gram-positive bacteria.
|
70 |
An evaluation of pocket-model, numerical readout breath alcohol testing instrumentsVan Tassel, William Edward 15 November 2004 (has links)
Eight small-scale breath alcohol measurement devices were tested for accuracy, precision and the ability to not yield false positive and false negative readings. These pocket-sized breath testers (PMBTs), which provided numerical readout of BrAC to the 100th of a percent, were smaller than evidential and preliminary breath test instruments (EBTs and PBTs). The smallest devices were approximately the same size of a cigarette lighter. Designed to provide drinkers feedback about their individual alcohol levels, the PMBTs ranged in price from $40-100 USD.
The devices were first tested under laboratory conditions with alcohol solution simulators providing the alcoholic samples. They were then tested with human drinkers, under controlled field conditions. Each device was tested at multiple alcohol levels.
Two of the eight PMBTs failed to complete all levels of testing and were excluded from the study. All PMBTs demonstrated the ability to not yield false positive and false negative readings. No device met NHTSA performance criteria for accuracy (systematic error) in testing EBTs at every alcohol level tested. An interaction between PMBTs and the alcohol test levels was found. Thus, accuracy was found to be dependent upon the alcohol level at which the devices were tested. No device met NHTSA performance criteria for precision in testing EBTs at every alcohol level tested. Precision varied depending on the testing condition. There was less precision under controlled field conditions than under laboratory conditions. Five of the six PMBTs that completed the testing overestimated BrAC; only one device read below actual BrAC.
Ramifications of the findings are discussed, regarding the overestimation and underestimation of BrAC and the possibility of manufacturers intentionally calibrating the devices to overestimate BrAC. Potential PMBT users are discussed and areas for future research are addressed.
|
Page generated in 0.074 seconds