Thesis (M.Phys.Ed.)--Memorial University of Newfoundland, 2004. / Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--La Crosse, 2002. / Includes bibliographical references.

Thesis (D.P.E.)--Springfield College, 2005. / Includes bibliographical references.

Thesis (Ph.D.)--University of Florida, 2005. / Typescript. Title from title page of source document. Document formatted into pages; contains 124 pages. Includes Vita. Includes bibliographical references.

Although the terms "Human Thermal Comfort" and "Indoor Air Quality (IAQ)" can be highly subjective, they still dictate the indoor climate design (HVAC design) of a building. In order to evaluate human thermal comfort and IAQ, one of three main tools are used, a) direct questioning the subjects about their thermal and air quality sensation (voting, sampling etc.), b) measuring the human thermal comfort by recording the physical parameters such as relative humidity, air and radiation temperature, air velocities and concentration gradients of pollutants or c) by using numerical simulations either including or excluding detailed thermo-physiological models. The application of the first two approaches can only take place in post commissioning and/or testing phases of the building. Use of numerical techniques can however be employed at any stage of the building design. With the rapid development in computational hard- and software technology, the costs involved in numerical studies has reduced compared to detailed tests. Employing numerical modelling to investigate human thermal comfort and IAQ however demand thorough verification and validation studies. Such studies are used to understand the limitations and application of numerical modelling of human thermal comfort and IAQ in indoor climates. This PhD research is an endeavour to verify, validate and apply, numerical simulation for modelling heat transfer and respiration of occupants in indoor climates. Along with the investigations concerning convective and radiation heat transfer between the occupants and their surroundings, the work focuses on detailed respiration modelling of sedentary human occupants. The objectives of the work have been to: verify the convective and radiation numerical models; validate them for buoyancy-driven flows due to human occupants in indoor climates; and apply these validated models for investigating human thermal comfort and IAQ in a real classroom for which field study data was available. On the basis of the detailed verification, validation and application studies, the findings are summarized as a set of guidelines for simulating human thermal comfort and IAQ in indoor climates. This PhD research involves the use of detailed human body geometries and postures. Modelling radiation and investigating the effect of geometrical posture has shown that the effective radiation area varies significantly with posture. The simulation results have shown that by using an effective radiation area factor of 0.725, estimated previously (Fanger, 1972) for a standing person, can lead to an underestimation of effective radiation area by 13% for the postures considered. Numerical modelling of convective heat transfer and respiration processes for sedentary manikins have shown that the SST turbulence model (Menter, 1994) with appropriate resolution of near wall region can simulate the local air velocity, temperature and heat transfer coefficients to a level of detail required for prediction of thermal comfort and IAQ. The present PhD work has shown that in a convection dominated environment, the detailed seated manikins give rise to an asymmetrical thermal plume as compared to the thermal plumes generated by simplified manikins or point sources. Validated simulation results obtained during the present PhD work have shown that simplified manikins can be used without significant limitations while investigating IAQ of complete indoor spaces. The use of simplified manikins however does not seem appropriate when simulating detailed respiration effects in the immediate vicinity of seated humans because of the underestimation in the amount of re-inhaled CO2 and pollutants from the surroundings. Furthermore, the results have shown that due to the simplification in geometrical form of the nostrils, the CO2 concentration is much higher near the face region (direct jet along the nostrils) as compared to a detailed geometry (sideways jet). Simulating the complete respiration cycle has shown that a pause between exhalation and inhalation has a significant effect on the amount of re-inhaled CO2. Previous results have shown the amount of re-inhaled CO2 to range between 10 - 19%. The present study has shown that by considering the pause, this amount of re-inhaled CO2 falls down to values lower than 1%. A comparison between the simplified and detailed geometry has shown that a simplified geometry can cause an underestimation in the amount of re-inhaled CO2 by more than 37% as compared to a detailed geometry. The major contribution to knowledge delivered by this PhD work is the provision of a validated seated computational thermal manikin. This PhD work follows a structured verification and validation approach for conducting CFD simulations to predict human thermal comfort and indoor air quality. The work demonstrates the application of the validated model to a classroom case with multiple occupancy and compares the measured results with the simulation results. The comparison of CFD results with measured data advocates the use of CFD and visualizes the importance of modelling thermal manikins in indoor HVAC design rather than designing the HVAC by considering empty spaces as the occupancy has a strong influence on the indoor air flow. This PhD work enables the indoor climate researchers and building designers to employ simplified thermal manikin to correctly predict the mean flow characteristics in indoor surroundings. The present work clearly demonstrates the limitation of the PIV measurement technique, the importance of using detailed CFD manikin geometry when investigating the phenomena of respiration in detail and the effect of thermal plume around the seated manikin. This computational thermal manikin used in this work is valid for a seated adult female geometry.

The main objective of this work is to determine the atomic structure of mammalian respiratory complex I. Mitochondrial complex I (also known as NADH:ubiquinone oxidoreductase) is one of the central enzymes in the oxidative phosphorylation pathway. It couples electron transfer between NADH and ubiquinone to proton translocation across the inner mitochondrial membrane, contributing to cellular energy production. Complex I is the largest and most elaborate protein assembly of the respiratory chain with a total mass of 970 kilodaltons. It consists of 14 conserved ‘core subunits’ and 31 mitochondria-specific ‘supernumerary subunits’. Together they form a giant, Lshaped molecule, with one arm buried in the mitochondrial membrane and another protruding into the mitochondrial matrix. Here, a novel method for the purification of ovine (Ovis aries) complex I was developed and suitable conditions for cryo-EM imaging established, after extensive screening of detergents and additives. Cryo-EM images were acquired with the recently developed direct electron detector and processed using the latest software. This allowed the solution of the nearly complete atomic model of mitochondrial complex I at 3.9 Å resolution. The membrane part of the complex contains 78 transmembrane helices, mostly contributed by conserved antiporter-like subunits responsible for proton translocation. These helices are stabilized by tightly bound lipids (including cardiolipins). The hydrophilic arm harbours flavin mononucleotide and 8 iron–sulfur clusters involved in electron transfer. Supernumerary subunits build a scaffold around the conserved core, strongly stabilizing the complex. Additionally, subunits containing cofactors (NADPH, zinc ion and phosphopantetheine) may play a regulatory role. Two distinct conformations of the complex are observed, which may describe the active and deactive states or reflect conformations occurring during the catalytic cycle of the enzyme. Currently this is the most detailed model of this molecular machine, providing insight into the mechanism, assembly and dysfunction of mitochondrial complex I. It also allows molecular analysis of numerous disease-causing mutations, and so the structure may serve as a stepping-stone for future medical developments.

Made available in DSpace on 2014-06-11T19:28:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-28Bitstream added on 2014-06-13T19:16:24Z : No. of bitstreams: 1 bicalho_es_me_jabo.pdf: 503292 bytes, checksum: d2ce2166bc9f68e6b65aa37ca5a4615c (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A emissão de CO2 do solo (FCO2) é influenciada por processos físicos, químicos e biológicos que afetam a produção de CO2 no interior do solo e o seu transporte para a atmosfera, variando no tempo e no espaço em função das condições ambientais e do manejo agrícola da área. O objetivo deste estudo foi investigar a correlação existente entre os padrões de estrutura de variabilidade espacial e temporal de FCO2 e atributos do solo, em área de cana-de-açúcar sob sistema de manejo cana crua, por meio de dimensão fractal (DF), derivada a partir de variogramas isotrópicos e anisotrópicos em diferentes escalas espaciais. A área experimental constituiu-se de uma malha regular de 60 × 60 m contendo 141 pontos espaçados em distâncias mínimas que variaram de 0,5 a 10 m. A emissão de CO2, temperatura e umidade do solo foram avaliadas durante 7 dias, sendo determinados os atributos físico e químicos do solo em amostragem na profundidade de 0,0 a 0,1 m. A média de FCO2 variou de 1,26 a 1,77 μmol m-2 s-1 ao longo dos dias, com dependência temporal na média e longa escalas, em alcances superiores a 20 m. Apesar do comportamento isotrópico observado para FCO2, seus valores de DF, calculados para diferentes direções, evidenciaram maior variabilidade temporal na direção paralela à linha de plantio, indicando influência das práticas de manejo adotadas na área. A variabilidade espacial de FCO2 foi mais bem evidenciada na média (20 a 30 m) e longa (40 a 60 m) escalas, com sua estrutura de variabilidade, caracterizada pelo fractograma, correlacionando-se significativamente com a maioria dos atributos do solo e apresentando comportamento similar à observada para a temperatura do solo e volume total de poros. Além disso, os fractogramas permitiram observar o comportamento da dependência espacial e temporal de FCO2 e... / Soil CO2 emission (FCO2) is influenced by physical, chemical and biological factors that affect the production of CO2 in the soil and its transport to the atmosphere, varying in time and space as a function of environmental conditions and agricultural management. The aim of this study was to investigate the correlation between spatial and temporal variability patterns of FCO2 and soil properties in sugarcane area under green management by using fractal dimension (DF), derived from isotropic and anisotropic variogram at different spatial scales. The experimental area consisted of a regular grid of 60 × 60 m containing 141 points spaced at minimum distances ranging from 0.5 to 10 m. Soil CO2 emission, soil temperature and soil moisture were evaluated over a period of 7 days, and soil physical and chemical properties were determined by sampling at a depth of 0.0 to 0.1 m. The average of FCO2 ranged from 1.26 to 1.77 mol m-2 s-1 throughout the days, with temporal dependence in the medium and large scales, at ranges of more than 20 m. Despite the isotropic behavior observed for FCO2, their DF values, calculated for different directions, showed greater temporal variability in the direction parallel to the row, indicating the influence of area management. Spatial variability of FCO2 was better evidenced in the medium (20 to 30 m) and long (40 to 60 m) scales, with its variability structure, characterized by fractogram, significantly correlated with most soil properties and similar behaving to that observed for the soil temperature and total pore volume. In addition, fractograms allowed to observe the behavior of the spatial and temporal dependence... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:23:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-12-22Bitstream added on 2014-06-13T19:49:59Z : No. of bitstreams: 1 teixeira_db_me_jabo.pdf: 508270 bytes, checksum: 93d2af6f4bf67e9aab6a84ffe3f4ac1a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A emissão de CO2 do solo (FCO2) apresenta alta variabilidade espacial, sendo devida a grande dependência espacial existente nas propriedades do solo que a influenciam. Neste estudo objetivou-se (i) caracterizar e relacionar a variabilidade e a distribuição espacial da FCO2, temperatura do solo, porosidade livre de água (PLA), teor de matéria orgânica do solo (MO) e densidade do solo (Ds), (ii) avaliar a acurácia dos resultados fornecidos pelo método da krigagem ordinária (KO) e simulação sequencial Gaussiana (SSG), e (iii) avaliar a incerteza na predição da variabilidade espacial das FCO2 e demais propriedades utilizando a SSG. O estudo foi conduzido em uma malha amostral regular de 60 x 60 m2 com 141 pontos, com espaçamento mínimo variando de 0,50 a 10 m, instalada em área de cana-de-açúcar. Nestes pontos foram avaliados a FCO2, temperatura do solo, PLA, determinadas com base na média de 07 dias de avaliação, MO e Ds. Todas as variáveis apresentaram estrutura de dependência espacial, sendo ajustados modelos Gaussianos, esféricos e exponenciais. A configuração da malha amostral e possivelmente a presença de espessa camada de resíduos da cultura sobre o solo influenciaram a estrutura de variabilidade espacial da FCO2, temperatura e MO. FCO2 apresentou correlações positivas com a MO (r = 0,25, p < 0,05) e PLA (r = 0,27, p < 0,01) e negativa com a Ds (r = - 0,41, p < 0,01). No entanto, quando os valores digitais estimados espacialmente (N=8.833) são considerados, a PLA passa a ser a principal variável responsável pelas características espaciais da FCO2, apresentando correlação de 0,26 (p < 0,01). As simulações individuais propiciaram, para todas as variáveis analisadas, melhor reprodução das funções de distribuição acumuladas (fdac), e dos variogramas em comparação... / The soil CO2 emission (FCO2) has high spatial variability, which caused due to the strong spatial dependence in soil properties that influence it. This study aimed to (i) to characterize the variability and spatial distribution of FCO2, soil temperature, air-filled pore space (AFPS), soil organic matter (OM) and soil bulk density (BD) and related properties, (ii) evaluate the accuracy of the results provided by the method of ordinary kriging (OK) and sequential Gaussian simulation (SGS), and (iii) evaluate the uncertainty in predicting the spatial variability of FCO2 and other properties using the SSG. The study was conducted on an regular sampling grid with 141 points, with spacing ranging from 0.50 to 10 m, installed in a sugarcane area. In this place were evaluated FCO2, soil temperature, AFPS, were based on the average of 07 days of evaluation, OM and BD. All variables showed spatial dependence structure, and models adjusted Gaussian, spherical and exponential. The configuration of the sampling grid and the presence of intense layer of crop residues in the soil influenced the structure of spatial variability of FCO2, temperature, and OM. The FCO2 showed positive correlations with OM (r = 0.25, p <0.05) and AFPS (r = 0.27, p <0.01) and negatively with Ds (r = - 0.41, p <0.01). However, when the estimated spatially values are considered, the AFPS becomes the main variable responsible for the spatial characteristics of FCO2, showing correlation of 0.26 (p <0.01). The individual simulations led to all variables, better reproduction of the cumulative distribution functions (cdf), and variograms compared to OK and E-type estimate. The analysis results show strong similarities between the E-type estimates to those generated by the procedure of OK. The major uncertainties in predicting FCO2 were associated with areas with the highest... (Complete abstract click electronic access below)

ContextualizaÃÃo: A obtenÃÃo de uma boa sincronia paciente-ventilador consiste em um dos maiores desafios no manejo da ventilaÃÃo mecÃnica (VM). A ventilaÃÃo com pressÃo de suporte ou pressure support ventilation (PSV) à uma modalidade ventilatÃria amplamente utilizada no processo de desmame da VM. A ventilaÃÃo assistida proporcional ou proportional assist ventilation (PAV) à uma modalidade de suporte ventilatÃrio onde o ventilador gera assistÃncia proporcional e instantÃnea aos esforÃos do paciente. O Auto-Trak digital consiste em uma tecnologia capaz de ajustar automaticamente, ciclo a ciclo, os mecanismos de disparo e ciclagem durante o modo PSV. Objetivos: Determinar a influÃncia da mecÃnica respiratÃria sobre a assincronia paciente-ventilador durante os modos PSV, com e sem sistema de disparo e ciclagem automÃticos e na PAV, em modelo pulmonar mecÃnico e identificar padrÃes nas curvas de ventilaÃÃo apresentadas na tela do ventilador que sejam relacionadas aos tipos de assincronia investigados. MÃtodos: Trata-se de estudo experimental, de bancada utilizando o simulador pulmonar mecÃnico, ASL 5000Â. Estudaram-se trÃs perfis de mecÃnica respiratÃria: normal, obstrutivo e restritivo, com variaÃÃo do tempo inspiratÃrio neural 0,5, 1,0, 1,5 e 2,0 segundos, sendo a intensidade mÃxima do esforÃo muscular (Pmus) fixada em -7.5 cmH2O, durante a VM nos modos PSV e PAV, em cinco ventiladores de UTI, de circuito duplo, e um ventilador de circuito Ãnico. O Auto-Trak foi estudado quando disponÃvel no ventilador. Os desfechos primÃrios foram: tempo de retardo inspiratÃrio e tempo de assincronia de ciclagem identificando, neste segundo caso, dois tipos possÃveis, ciclagem tardia ou precoce. AlÃm disso, procedeu-se a uma anÃlise por inspeÃÃo visual comparativa entre as curvas de mecÃnica: fluxo, VC e Pmus do ASL 5000 e as curvas na tela grÃfica do ventilador mecÃnico de VC, fluxo e pressÃo x tempo, na tentativa de se identificar padrÃes associados à assincronia, que fossem passÃveis de identificaÃÃo pela simples observaÃÃo na tela do ventilador pulmonar. Resultados: Houve marcante influÃncia da mecÃnica respiratÃria sobre a assincronia paciente-ventilador. O tempo de retardo inspiratÃrio foi maior e clinicamente significativo (> 100 ms) no perfil obstrutivo de mecÃnica respiratÃria, e foi menor, muitas vezes zero, no ventilador de circuito Ãnico; a assincronia de ciclagem foi comum no perfil obstrutivo, sendo predominantemente do tipo ciclagem tardia, enquanto no perfil restritivo predominou o tipo ciclagem precoce. O emprego do Auto-trak eliminou a ocorrÃncia de assincronia do tipo auto-disparo no ventilador de circuito Ãnico. A anÃlise visual das curvas detectou padrÃes de traÃados da curva de fluxo x tempo que sÃo caracterÃsticos de assincronia do tipo ciclagem precoce e ciclagem tardia e passÃveis de identificaÃÃo por inspeÃÃo visual direta na tela do ventilador. ConclusÃo: as assincronias de disparo e ciclagem entre o paciente e o ventilador sÃo a regra e nÃo a exceÃÃo durante os modos PSV e PAV, sendo estas influenciadas pela mecÃnica respiratÃria. O emprego do sistema Auto-trakÂ, mostrou benefÃcio durante o uso do ventilador de circuito Ãnico com melhora substancial do disparo. A inspeÃÃo visual da curva de fluxo na tela do ventilador pode favorecer a identificaÃÃo destes tipos de assincronia. Palavras-chave: / Obtaining a good patient-ventilator synchrony is one of the biggest challenges in the management of mechanical ventilation (MV). Pressure support ventilation (PSV) is a ventilator mode widely used in the MV weaning process. Proportional assist ventilation (PAV) is a mode of ventilator support in which the ventilator generates assistance proportional and instant to the efforts of the patient. Digital Auto-TrakTM consists in a technology capable of automatically adjusting, cycle by cycle, the mechanisms of triggering and cycling in PSV mode. Objectives: To determine the influence of respiratory mechanics on patient-ventilator asynchrony during PSV mode, with and without automatic triggering and cycling system, and PAV, in a mechanic lung model and to identify patterns on ventilation curves presented on the ventilator screen, which are related to the types of asynchrony investigated. Methods: This is an experimental bench study using the mechanic lung model, ASL 5000TM. Three profiles of respiratory mechanics were studied: normal, obstructive and restrictive, with variation of neural inspiratory time of 0.5, 1.0, 1.5 and 2.0 seconds, with maximum intensity of muscle effort (Pmus) fixed in -7.5 cmH2O, during MV in PSV and PAV modes, in five ICU ventilators, with double limb, and in one single limb ventilator. Auto-TrakTM was studied when avaliable in the ventilator. Primary outcomes were: inspiratory delay time and cycling asynchrony time identifying, in the second case, two possible types, late or premature cycling. Furthermore, we proceeded to an analysis by visual inspection of the: flow, VT and Pmus curves of ASL 5000TM and the: VT, flow and pressure curves on the ventilator screen in an attempt to identify patterns associated to asynchrony that would be identified through simple observation. Results: There was a marked influence of respiratory mechanics on patient-ventilator asynchrony. The inspiratory delay time was higher and clinically significant in the obstructive profile of respiratory mechanics, and lower, many times âzeroâ, with the single limb ventilator. Cycling asynchrony was common in the obstructive profile, predominantly the late cycling type, while in the restrictive profile, the premature cycling type predominated. The use of Auto-TrakTM system eliminated the occurrence of auto triggering asynchrony type in the single limb ventilator. Visual analysis of the curves detected patterns of flow x time curves that are characteristic of premature and late cycling asynchrony types and which can be identified by direct visual inspection of the ventilator screen. Conclusion: Triggering and cycling asynchronies between the patient and the ventilator are the rule rather than the exception during PSV and PAV modes, which are influenced by respiratory mechanics. The use of Auto-TrakTM system showed benefit during the use of the single limb ventilator, with substantial improvement of the triggering. Visual inspection of the flow curve on the ventilator screen may favor the identification of these types of asynchrony.

Orientador: Everardo Andrade da Costa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-17T21:33:45Z (GMT). No. of bitstreams: 1 Teixeira_RodrigoUbiratanFranco_M.pdf: 1228242 bytes, checksum: d6745d36e991daad043696bd5b074b70 (MD5) Previous issue date: 2011 / Resumo: Para a avaliação objetiva da patência nasal são utilizados a rinometria acústica, rinomanometria e o peak flow nasal inspiratório (PFNI). Estes exames, com exceção do PFNI, são dispendiosos e complexos. Para utilização na Medicina do Trabalho e mesmo na prática clínica diária, faz-se necessário um método de mensuração simples, rápido, de baixo custo e confiável. Atualmente, os estudos tendem a correlacionar métodos que reúnem estas características, com aqueles métodos já bem documentados. Objetivos: comparar os resultados do PFNI com achados da Escala Analógica Visual (EVA), antes e após o uso de vasoconstritor nasal em indivíduos assintomáticos. Em um segundo momento, avaliar o PFNI entre indivíduos saudáveis e com queixas nasais obstrutivas. Forma de estudo: Artigo 1: Estudo de coorte em que a variável em questão é a ralação entre o PFNI e a EVA para obstrução nasal antes e após vasoconstrição nasal em indivíduos saudáveis; Artigo 2: Estudo transversal, em que a variável estudada é o comportamento do PFNI em uma população de indivíduos sem e com queixas nasais obstrutivas. Métodos: Dissertação realizada em formato alternativo composta de dois artigos. No primeiro foi feito uma correlação entre o resultado do PFNI e EVA antes e após vasoconstrição nasal de uma amostra de 60 sujeitos saudáveis. No segundo artigo foram avaliados 78 sujeitos com e sem sintomas nasais obstrutivos. Ambos estudos tiveram alocação de sujeitos de forma não randomizada. Resultados: No teste de regressão linear simples, o PFNI mostrou resultados significantes para obstrução nasal, rinorréia, prurido, espirros e lacrimejamento (p<0,001) e não apresentou significância para desvio de septo nasal (p=0,561). Encontrou-se uma correlação positiva entre PFNI e a pesquisa através da EVA (p<0,001). Houve significância estatística entre os valores encontrados no PFNI com rinite alérgica e idade (p=0,005 e p=0,023 respectivamente). O valor médio encontrado para EVA pré vasoconstrição foi de 4,1 e 2 após a vasoconstrição (variação de 44%). Em relação ao PFNI, a média encontrada foi de 151l/mim e de 178l/mim antes e após a vasoconstrição (variação de 20%). Conclusão: O PFNI mostrou ser um método confiável para detecção das alterações da patência nasal, tanto por causas obstrutivas quanto inflamatórias, com um nível de significância estatística aceitável. Apresentou forte correlação com a EVA, que é um método subjetivo muito utilizado para mensuração da obstrução nasal. É simples, fácil de manusear, pouco dispendioso e reprodutível. Por estas características descritas, pode ser usado como exame de triagem em Medicina do Trabalho. Entretanto, estudos com amostras maiores serão necessários para a normatização e sua utilização em massa / Abstract: For the objective assessment of nasal patency are used to acoustic rhinometry, rhinomanometry and nasal inspiratory peak flow (PFNI). These tests, except PFNI, are expensive and impractical. For use in occupational medicine and even in daily clinical practice, it is necessary a method for measuring simple, fast, inexpensive and reliable. Currently, studies tend to correlate methods that meet these characteristics, with other methods already well documented. Objectives: compare the results with findings PFNI EVA before and after using a nasal vasoconstrictor. In a second step, to evaluate the PFNI between healthy and obstructive nasal symptoms for allergic rhinitis. Study design: Article 1: A cohort study in which the variable is to determine the relationship between EVA Visual Analogue Scale) and PFNI for nasal obstruction before and after using a nasal vasoconstrictor. Article 2: A cross-sectional study in which the variable is the behavior of PFNI in a population of individuals. Methods: Essay held in alternate format consists of two articles. In the first article, was made a correlation between the result of PFNI and VAS before and after nasal vasoconstriction of a sample of 60 subjects. In the second article, was involve 78 subjects with and without symptoms of rhinitis. Both studies had allocation of subjects in a non-randomized. Results: In simple linear regression, the PFNI showed significant results for nasal obstruction, rhinorrhea, itching, sneezing and watery eyes (p<0.001). There was also a correlation between the presence of nasal septal deviation and PFNI (p=0.561). We found a positive correlation, the Spearman test between PFNI and research through the VAS (p<0.001). There was no statistical significance between the values found in PFNI with allergic rhinitis and age (p=0.005 and p=0.023 respectively). The mean value for VAS pre vasoconstriction was 4.1 and 2 after vasoconstriction. This represented a 44% variation between measurements. Regarding the values of PFNI, the average found in the pre measure vasoconstriction was 151l/min and 178l/min after vasoconstriction, an increase of 20%. At the moment pre vasoconstrictor, the change of a point on the average VAS represents a decrease of 3.8% in the average PFNI. In the post, each one point increase in the average value of EVA, corresponds to a decrease of 4.5% on average PFNI. Conclusion: The PFNI proved to be a reliable method for detecting larger studies are needed for a proper understanding of the method and its widespread use. changes in nasal patency by both inflammatory and obstructive causes, with an acceptable level of statistical significance, simple, easy to handle, inexpensive and reproducible. Showed strong correlation with the EVA, which is a very subjective method used to measure the nasal obstruction. Due to its characteristics described, can be used as a screening test in occupational medicine. However, larger studies are needed for a proper understanding of the method and its widespread use / Mestrado / Epidemiologia / Mestre em Saude Coletiva