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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Rozdíl spotřeby dýchaného média mezi muži a ženami při jednotné zátěži v přístrojovém potápění / Differences in inhalation between men and famales during the identic scuba diving output

Rosenkranzová, Michaela January 2016 (has links)
Name: : The difference of consumption of a medium being inhaled between a man and a woman at the same level of endurance in scuba diving. Goals: The primary goal of this work, is to determine if and how is the amount of the inhaled medium depending on the gender of the divers. Compare the consumption between men and women while being faced with the same amount of stress, meaning during a united profile of a dive, try to maximize the decrease of the influence of stress factors. Confirm or deny the hypothesis that men show higher values of the inhaled medium. Methods: The theoretical part of this paper, was created based on the research of the appropriate literature. To obtain all the data, there was used the method of experiments, the results were then analyzed, compared and than statistically evaluated using the Students T- test. Probandi (n=10+10) took part in a 30 minute long and 20 meters deep dive in Bořená hora, during which their consumption of the inhaled medium was recorded every 5 seconds using a special underwater computer with a probe. Results: It was found out that men, during the same dive, consume more air than women because of their higher body weight. Key words: scuba diving, air, sex, respirator, minute ventilation
2

Análise de padrão ventilatório, trocas gasosas e mecânica ventilatória em juvenis e adultos de Chelonoidis carbonarius (Spix, 1824) / Analyses of ventilatory pattern, gas exchange and breathing mechanics in juvenile and adult Chelonoidis carbonarius (Spix, 1824)

Oliveira, Paulo Roberto Custodio de 26 March 2018 (has links)
A compreensão da relação entre ventilação, troca gasosa e mecânica ventilatória é de vital importância na busca do entendimento do funcionamento do sistema respiratório. Ao longo do desenvolvimento animal, mudanças no tamanho corpóreo necessitam de reajustes na relação entre seus componentes em nível estrutural e funcional. O tamanho corporal, além de outros fatores, é um agente de influência em variáveis relacionadas ao sistema respiratório em vertebrados. O conhecimento sobre o funcionamento do sistema respiratório em répteis é restrito a algumas espécies, portanto, o presente trabalho teve como objetivo analisar o padrão ventilatório, troca de gases e a mecânica ventilatória em juvenis e adultos de Chelonoidis carbonarius (Cryptodira: Testudinidae). Os animais (n=10) pesando entre 40 gramas a 2,5 quilogramas aproximadamente e sob a condição de normóxia, foram submetidos à respirometria aberta para determinação do padrão ventilatório, do consumo de oxigênio e da produção de gás carbônico em diferentes temperaturas (15, 25 e 35°C). Os volumes pulmonares, complacência estática, complacência dinâmica, resistência pulmonar e o trabalho mecânico da ventilação foram averiguados em juvenis e adultos nas condições supino, prona e para os pulmões isolados das vísceras, verificando assim a influência dessas condições sobre a mecânica ventilatória do sistema respiratório. Os resultados obtidos apresentaram padrões ventilatórios periódicos em todas as temperaturas estudadas. O volume corrente não apresentou mudanças significativas com o aumento da temperatura, enquanto o aumento da frequência respiratória levou ao acréscimo da ventilação por minuto nas comparações entre 15-35°C. O consumo de oxigênio e a excreção de gás carbônico aumentaram com a temperatura e juvenis apresentaram maiores valores comparado a adultos. Tratando-se da mecânica ventilatória, adultos apresentaram diferença para o volume pulmonar de repouso na comparação entre a posição prona e supino e para o volume pulmonar máximo comparado a posição supino com os pulmões isolados. As complacências estática e dinâmica, juntamente com a resistência, padronizadas pela massa corpórea e pelos volumes pulmonares, demonstraram diferenças ao comparar os pulmões isolados com a posição supino. O trabalho mecânico mostrou ser dependente do volume ao invés da frequência em todas as condições testadas. Os resultados apresentados indicaram que mediante mudanças na ventilação, causada pelo aumento da temperatura, juvenis e adultos de Chelonoidis carbonarius, regularam a ventilação aumentando a frequência respiratória e mantiveram os valores do volume corrente a fim de garantir os níveis de trabalho mecânico. / The understanding of the relationship between ventilation, gas exchange and ventilatory mechanics is of vital importance in the search to understand the functioning of the respiratory system. Throughout animal development, changes in body size need adjustments in the relationship between its components at a structural and functional level. Body size, besides other factors, is an agent of influence in variables related to the respiratory system in vertebrates. The knowledge about the function of the respiratory system in reptiles is restricted to some species, so the present work aimed to analyze ventilatory pattern, gas consumption and respiratory mechanics in juveniles and adults of Chelonoidis carbonarius (Cryptodira: Testudinidae). The animals (n = 10) weighing between 40 grams to approximately 2,5 kilograms and under normoxic conditions, were submitted to open respirometry to determine the ventilatory pattern, the oxygen consumption and the production of carbon dioxide at different temperatures (15, 25 and 35°C). Pulmonary volumes, static compliance, dynamic compliance, pulmonary resistance and work of breathing were investigated in juveniles and adults in supine, prone and isolated lung, thus verifying the influence of these conditions on the ventilatory mechanics of the respiratory system. The obtained results presented periodic ventilatory patterns in all the studied temperatures. The tidal volume did not show significant changes with increased temperature, while the raise in breathing frequency led to greater minute ventilation when comparing 15 and 35°C. Oxygen consumption and carbon dioxide excretion increased with temperature and juveniles presented higher values compared to adults. Regarding mechanics, adults presented a significant difference for resting volume in the comparison between the prone and supine position and for the maximum lung volume compared to the supine position with the isolated lungs. Body mass as well as lung volume standardized static and dynamic compliances and resistance showed significant differences when comparing the isolated lungs with the supine position. The mechanical work was shown to be volume dependent rather than frequency in all tested conditions. The results indicated that through changes in ventilation caused by increasing temperature, juveniles and adults of Chelonoidis carbonarius regulated ventilation by increasing minute ventilation and maintained tidal volume values in order to guarantee levels of work of breathing.
3

Análise de padrão ventilatório, trocas gasosas e mecânica ventilatória em juvenis e adultos de Chelonoidis carbonarius (Spix, 1824) / Analyses of ventilatory pattern, gas exchange and breathing mechanics in juvenile and adult Chelonoidis carbonarius (Spix, 1824)

Paulo Roberto Custodio de Oliveira 26 March 2018 (has links)
A compreensão da relação entre ventilação, troca gasosa e mecânica ventilatória é de vital importância na busca do entendimento do funcionamento do sistema respiratório. Ao longo do desenvolvimento animal, mudanças no tamanho corpóreo necessitam de reajustes na relação entre seus componentes em nível estrutural e funcional. O tamanho corporal, além de outros fatores, é um agente de influência em variáveis relacionadas ao sistema respiratório em vertebrados. O conhecimento sobre o funcionamento do sistema respiratório em répteis é restrito a algumas espécies, portanto, o presente trabalho teve como objetivo analisar o padrão ventilatório, troca de gases e a mecânica ventilatória em juvenis e adultos de Chelonoidis carbonarius (Cryptodira: Testudinidae). Os animais (n=10) pesando entre 40 gramas a 2,5 quilogramas aproximadamente e sob a condição de normóxia, foram submetidos à respirometria aberta para determinação do padrão ventilatório, do consumo de oxigênio e da produção de gás carbônico em diferentes temperaturas (15, 25 e 35°C). Os volumes pulmonares, complacência estática, complacência dinâmica, resistência pulmonar e o trabalho mecânico da ventilação foram averiguados em juvenis e adultos nas condições supino, prona e para os pulmões isolados das vísceras, verificando assim a influência dessas condições sobre a mecânica ventilatória do sistema respiratório. Os resultados obtidos apresentaram padrões ventilatórios periódicos em todas as temperaturas estudadas. O volume corrente não apresentou mudanças significativas com o aumento da temperatura, enquanto o aumento da frequência respiratória levou ao acréscimo da ventilação por minuto nas comparações entre 15-35°C. O consumo de oxigênio e a excreção de gás carbônico aumentaram com a temperatura e juvenis apresentaram maiores valores comparado a adultos. Tratando-se da mecânica ventilatória, adultos apresentaram diferença para o volume pulmonar de repouso na comparação entre a posição prona e supino e para o volume pulmonar máximo comparado a posição supino com os pulmões isolados. As complacências estática e dinâmica, juntamente com a resistência, padronizadas pela massa corpórea e pelos volumes pulmonares, demonstraram diferenças ao comparar os pulmões isolados com a posição supino. O trabalho mecânico mostrou ser dependente do volume ao invés da frequência em todas as condições testadas. Os resultados apresentados indicaram que mediante mudanças na ventilação, causada pelo aumento da temperatura, juvenis e adultos de Chelonoidis carbonarius, regularam a ventilação aumentando a frequência respiratória e mantiveram os valores do volume corrente a fim de garantir os níveis de trabalho mecânico. / The understanding of the relationship between ventilation, gas exchange and ventilatory mechanics is of vital importance in the search to understand the functioning of the respiratory system. Throughout animal development, changes in body size need adjustments in the relationship between its components at a structural and functional level. Body size, besides other factors, is an agent of influence in variables related to the respiratory system in vertebrates. The knowledge about the function of the respiratory system in reptiles is restricted to some species, so the present work aimed to analyze ventilatory pattern, gas consumption and respiratory mechanics in juveniles and adults of Chelonoidis carbonarius (Cryptodira: Testudinidae). The animals (n = 10) weighing between 40 grams to approximately 2,5 kilograms and under normoxic conditions, were submitted to open respirometry to determine the ventilatory pattern, the oxygen consumption and the production of carbon dioxide at different temperatures (15, 25 and 35°C). Pulmonary volumes, static compliance, dynamic compliance, pulmonary resistance and work of breathing were investigated in juveniles and adults in supine, prone and isolated lung, thus verifying the influence of these conditions on the ventilatory mechanics of the respiratory system. The obtained results presented periodic ventilatory patterns in all the studied temperatures. The tidal volume did not show significant changes with increased temperature, while the raise in breathing frequency led to greater minute ventilation when comparing 15 and 35°C. Oxygen consumption and carbon dioxide excretion increased with temperature and juveniles presented higher values compared to adults. Regarding mechanics, adults presented a significant difference for resting volume in the comparison between the prone and supine position and for the maximum lung volume compared to the supine position with the isolated lungs. Body mass as well as lung volume standardized static and dynamic compliances and resistance showed significant differences when comparing the isolated lungs with the supine position. The mechanical work was shown to be volume dependent rather than frequency in all tested conditions. The results indicated that through changes in ventilation caused by increasing temperature, juveniles and adults of Chelonoidis carbonarius regulated ventilation by increasing minute ventilation and maintained tidal volume values in order to guarantee levels of work of breathing.
4

Validation of Spiropalm 6MWT Hand-held Spirometer against Jaeger Oxycon Pro, focusing on minute ventilation

Båtsby, Frida January 2020 (has links)
Introduction: Ergospirometry is used to evaluate working capacity and assess whether limitations may originate from circulation or respiration. It is typically based on an ordinary exercise test, in conjunction with respiratory analysis. A six-minute walk test (6MWT) may be used to asses a patients functional capacity. The subject walks a 30-meter-long hallway as far as possible for six minutes. Equipment is now available to analyse ventilation simultaneously. The purpose of the study was to validate Spiropalm 6MWT Hand-held Spirometer against Jaeger Oxycon Pro, focusing on minute ventilation. Method and material: A convenience sample of 30 young, healthy adults between the age of 18-32 participated in the study at Örebro University. Minute ventilation was measured with Spiropalm 6MWT Handheld Spirometer (COSMED, Rome, Italy) and Jaeger Oxycon Pro (Viasys Healthcare, Pennsylvania, USA) during two walking tests on treadmill at three intensity levels (velocities). A paired Students t-test was used for comparison between the equipments and between the three intensity levels in regard to minute ventilation and heart rate. Result: The result showed a statistically significant difference between the two equipments, focusing on minute ventilation, at intensity levels 1 and 2, but not for level 3. The Spiropalm shows consistently lower values. There was no difference between the heart rate during the two trials. Conclusion: Spiropalm consistently has lower values of VE than the Jaeger-system, this can be the cause of the difference between the equipments during lower intensity levels, although not high enough for a difference at level 3. There was no difference in heart rate between the two trials at any of the intensity levels, this shows that the subjects were well rested between the trials. / Introduktion: Ergospirometri används för att utvärdera en individs arbetsfysiologi och se om någons begränsningar har sitt ursprung cirkulatoriskt eller respiratoriskt. Undersökningen är baserad på ett vanligt arbetsprov i samband med analys av lungfunktion. Ett sex minuters gångtest (6MWT) kan användas för att utvärdera en patients funktionella kapacitet. Personen får gå i en 30 meter lång korridor så långt som möjligt under sex minuter. Det finns nu utrustning för att analysera lungfunktionen under pågående test. Syftet med studien var att validera Spiropalm 6MWT Hand-held Spirometer mot Jaeger Oxycon Pro med fokus på minutventilation. Metod och material: En studiepopulation på 30 unga, friska vuxna mellan åldrarna 18–32 deltog i studien på Örebro Universitet. Minutventilation mättes med Spiropalm 6MWT Handheld Spirometer (COSMED, Rom, Italien) och Jaeger Oxycon Pro (Viasys Healthcare, Pennsylvania, USA) under två gångtest på gångband under tre olika intensitetsnivåer (hastigheter). Ett parat Students t-test användes vid jämförelse mellan utrustningarna och mellan de tre olika intensitetsnivåerna med avseende på minutventilation och hjärtfrekvens. Resultat: Resultatet visade att det var en statistiskt signifikant skillnad mellan utrustningarna med fokus på minutventilation på intensitetsnivå 1 och 2, men inte på intensitetsnivå 3. Det förelåg inte någon skillnad i hjärtfrekvens mellan de två testerna. Konklusion: Spiropalm analyserar konsekvent lägre än Jaeger-systemet, detta kan vara anledningen till skillnaden mellan utrustningarna på lägre intensitetsnivåer, dock inte tillräckligt högt för skillnad på intensitetsnivå 3. Hjärtfrekvensen var densamma under båda testen på alla intensitetsnivåerna vilket visar på att försökspersonerna var väl utvilade mellan testerna.
5

Fyziologická odezva závodníků lodní třídy Fireball při modelovém závodu v okruhovém jachtingu / Physiological response of competitors Fireball dinghy class in the model sailing race.

Lambl, David January 2012 (has links)
Title: Physiological response of competitors Fireball dinghy class in the model sailing race. Objectives: The main intention of the thesis is to detect the physical demands (difficulties) of sailing boat race categorized as Fireball double crew. The variables of physiological response to the load of competitors recorded are being measured using simulated race under laboratory conditions. At that point, this opportunity enabled us to carry out further comparisons and examine the physical demands of individual post at various directions of wind. Methods: The entire investigation of detecting physiological functions of competitors will be carried out noninvasively throughout the simulation of sailing using metabolic analyser tool and sport tester. From the feedback, we will obtained figures and originate the physiological response of human body to the load. Due to the investigation is being implemented on the double crew boat Fireball; both competitors (crew/helmsman) performing different tasks will be simulated and examined individually. Simulated race will last 24 minutes and competitors will have to face different wind courses, precisely cruising upwind, crosswind and tailwind. Results: From the measured results, we can state that most of the time during simulated race, the performance of racers...
6

Taux quotidiens d’inhalation et paramètres cardio-pulmonaires chez l’humain selon les données publiées en rapport au double marquage des molécules d’eau pour l’analyse du risque

Brochu, Pierre 10 1900 (has links)
L’objectif de cette étude est de déterminer certains paramètres respiratoires et cardiovasculaires chez des sujets de tous âges pour utilisation, à titre d’intrants physiologiques, en modélisation toxicocinétique et en analyse du risque toxique. La base de données utilisée est tirée de la littérature. Il s’agit de mesures portant sur la dépense d’énergie quotidienne de base et la dépense d’énergie quotidienne de totale obtenues, l’une par calorimétrie indirecte, l’autre par double marquage isotopique des molécules d’eau. Selon le type d’unité retenu, les valeurs les plus élevées au 99e centile des taux quotidiens d’inhalation sont obtenues chez des adolescentes et des femmes âgées de 11 à 55 ans souffrant d’embonpoint ou d’obésité, durant leur 36e semaine de grossesse (47,31 m³/jour), ainsi que chez des garçons de poids corporel normal âgés de 2,6 à moins de 6 mois (1,138 m³/kg-jour) et de 10 à moins de 16,5 ans (22,29 m³/m²-jour). Chez les enfants et les adolescents de poids corporel normal âgés de 5 à moins de 16.5 ans, les valeurs pour l’écart entre le 2,5e au 99e centile sont généralement plus élevées que celles obtenues chez les sujets plus âgés : taux de ventilation minute, 0,132 à 0,774 L/kg-min ou 4,42 à 21,69 L/m²-min versus 0,076 à 0,461 L/kg-min ou 2,80 à 16,99 L/m²-min; taux de ventilation alvéolaire, 0,093 à 0,553 L/kg-min ou 3,09 à 15,53 L/m²-min versus 0,047 à 0,312 L/kg-min ou 1,73 à 11,63 L/m²-min; débit cardiaque, 0,065 à 0,330 L/kg-min ou 2,17 à 9,46 L/m²-min versus 0,045 à 0,201 L/kg-min ou 1,63 à 7,24 L/m²-min; ratio de ventilation-perfusion, 1,12 à 2,16 versus 0,78 à 2,40. Il faut conclure que les apports inhalés en polluants, exprimés en ug/kg-min ou ug/m²-min sont plus élevés chez les enfants que chez les sujets plus âgés pour des concentrations d’exposition comparables. D’autres données montrent qu’il en est de même pour les apports inhalés par unité de poids corporel chez les femmes enceintes et les femmes qui allaitent par rapport à des sujets males d’âge comparable. L’ensemble des résultats obtenus suggère notamment que les valeurs des NOAELH de Santé Canada pourraient être abaissées par un facteur de 2,6 par utilisation du 99e centile le plus élevé des taux quotidiens d’inhalation chez les enfants; le taux de ventilation minute de 20,83 L/min approximé pour une journée de travail de 8 heures peut être considéré comme étant conservateur ; par contre, l’utilisation du taux quotidien d’inhalation de 0,286 m³/kg-jour (c.-à-d. 20 m³/jour pour un adulte de poids corporel de 70 kg) est inappropriée en analyse et gestion du risque lorsqu’appliquée à l’ensemble de la population. / The aim of the present study is to determine some respiratory and cardiovascular parameters in subjects of all ages for use, as physiological inputs, in toxicokinetic simulations and toxic risk assessment. The database used is taken from the literature. Data of interest include basal energy expenditures and total daily energy expenditures obtained by indirect calorimetry and doubly labeled water measurements respectively. Depending upon the unit value chosen, the highest 99th percentiles for daily inhalation rates were found in overweight/obese females 11 to 55 years old during their 36th weeks of pregnancy (47.31 m³/day), as well as in normal-weight boys aged 2.6 to less than 6 months(1.138 m³/kg-day) and 10 to less than 16.5 years (22.29 m³/m²-day). Generally higher values for the 2.5th up to 99th percentile were found in normal-weight children and teenagers aged 5 to less than 16.5 years compared to those for older individuals: minute ventilation rate, 0.132 to 0.774 L/kg-min or 4.42 to 21.69 L/m²-min versus 0.076 to 0.461 L/kg-min or 2.80 to 16.99 L/m²-min; alveolar ventilation rate, 0.093 to 0.553 L/kg-min or 3.09 to 15.53 L/m²-min versus 0.047 to 0.312 L/kg-min or 1.73 to 11.63 L/m²-min; cardiac output, 0.065 to 0.330 L/kg-min or 2.17 to 9.46 L/m²-min versus 0.045 to 0.201 L/kg-min or 1.63 to 7.24 L/m²-min; ventilation-perfusion ratio, 1.12 to 2.16 versus 0.78 to 2.40. Higher intakes of air pollutants by the respiratory tract expressed in ug/kg-min or ug/m²-min are expected in children compared to older individuals for identical exposure concentrations.The same conclusion is reached in pregnant and lactating females compared to male subjects of same ages, for intakes expressed per unit of bodyweight. The aggregate results obtained notably suggests that NOAELH values from Health Canada could be decreased by a factor of 2.6 by the use of the highest 99th percentiles for daily inhalation rates found in children; the minute ventilation rate of 20.83 L/min approximated based on an 8-hour workday may be considered as being conservative; however, the use of the daily inhalation rate of 0.286 m³/kg-day (i.e. 20 m³/day for a 70-kg adult) is inappropriate in risk assessment and management when applied to the whole population.
7

Taux quotidiens d’inhalation et paramètres cardio-pulmonaires chez l’humain selon les données publiées en rapport au double marquage des molécules d’eau pour l’analyse du risque

Brochu, Pierre 10 1900 (has links)
L’objectif de cette étude est de déterminer certains paramètres respiratoires et cardiovasculaires chez des sujets de tous âges pour utilisation, à titre d’intrants physiologiques, en modélisation toxicocinétique et en analyse du risque toxique. La base de données utilisée est tirée de la littérature. Il s’agit de mesures portant sur la dépense d’énergie quotidienne de base et la dépense d’énergie quotidienne de totale obtenues, l’une par calorimétrie indirecte, l’autre par double marquage isotopique des molécules d’eau. Selon le type d’unité retenu, les valeurs les plus élevées au 99e centile des taux quotidiens d’inhalation sont obtenues chez des adolescentes et des femmes âgées de 11 à 55 ans souffrant d’embonpoint ou d’obésité, durant leur 36e semaine de grossesse (47,31 m³/jour), ainsi que chez des garçons de poids corporel normal âgés de 2,6 à moins de 6 mois (1,138 m³/kg-jour) et de 10 à moins de 16,5 ans (22,29 m³/m²-jour). Chez les enfants et les adolescents de poids corporel normal âgés de 5 à moins de 16.5 ans, les valeurs pour l’écart entre le 2,5e au 99e centile sont généralement plus élevées que celles obtenues chez les sujets plus âgés : taux de ventilation minute, 0,132 à 0,774 L/kg-min ou 4,42 à 21,69 L/m²-min versus 0,076 à 0,461 L/kg-min ou 2,80 à 16,99 L/m²-min; taux de ventilation alvéolaire, 0,093 à 0,553 L/kg-min ou 3,09 à 15,53 L/m²-min versus 0,047 à 0,312 L/kg-min ou 1,73 à 11,63 L/m²-min; débit cardiaque, 0,065 à 0,330 L/kg-min ou 2,17 à 9,46 L/m²-min versus 0,045 à 0,201 L/kg-min ou 1,63 à 7,24 L/m²-min; ratio de ventilation-perfusion, 1,12 à 2,16 versus 0,78 à 2,40. Il faut conclure que les apports inhalés en polluants, exprimés en ug/kg-min ou ug/m²-min sont plus élevés chez les enfants que chez les sujets plus âgés pour des concentrations d’exposition comparables. D’autres données montrent qu’il en est de même pour les apports inhalés par unité de poids corporel chez les femmes enceintes et les femmes qui allaitent par rapport à des sujets males d’âge comparable. L’ensemble des résultats obtenus suggère notamment que les valeurs des NOAELH de Santé Canada pourraient être abaissées par un facteur de 2,6 par utilisation du 99e centile le plus élevé des taux quotidiens d’inhalation chez les enfants; le taux de ventilation minute de 20,83 L/min approximé pour une journée de travail de 8 heures peut être considéré comme étant conservateur ; par contre, l’utilisation du taux quotidien d’inhalation de 0,286 m³/kg-jour (c.-à-d. 20 m³/jour pour un adulte de poids corporel de 70 kg) est inappropriée en analyse et gestion du risque lorsqu’appliquée à l’ensemble de la population. / The aim of the present study is to determine some respiratory and cardiovascular parameters in subjects of all ages for use, as physiological inputs, in toxicokinetic simulations and toxic risk assessment. The database used is taken from the literature. Data of interest include basal energy expenditures and total daily energy expenditures obtained by indirect calorimetry and doubly labeled water measurements respectively. Depending upon the unit value chosen, the highest 99th percentiles for daily inhalation rates were found in overweight/obese females 11 to 55 years old during their 36th weeks of pregnancy (47.31 m³/day), as well as in normal-weight boys aged 2.6 to less than 6 months(1.138 m³/kg-day) and 10 to less than 16.5 years (22.29 m³/m²-day). Generally higher values for the 2.5th up to 99th percentile were found in normal-weight children and teenagers aged 5 to less than 16.5 years compared to those for older individuals: minute ventilation rate, 0.132 to 0.774 L/kg-min or 4.42 to 21.69 L/m²-min versus 0.076 to 0.461 L/kg-min or 2.80 to 16.99 L/m²-min; alveolar ventilation rate, 0.093 to 0.553 L/kg-min or 3.09 to 15.53 L/m²-min versus 0.047 to 0.312 L/kg-min or 1.73 to 11.63 L/m²-min; cardiac output, 0.065 to 0.330 L/kg-min or 2.17 to 9.46 L/m²-min versus 0.045 to 0.201 L/kg-min or 1.63 to 7.24 L/m²-min; ventilation-perfusion ratio, 1.12 to 2.16 versus 0.78 to 2.40. Higher intakes of air pollutants by the respiratory tract expressed in ug/kg-min or ug/m²-min are expected in children compared to older individuals for identical exposure concentrations.The same conclusion is reached in pregnant and lactating females compared to male subjects of same ages, for intakes expressed per unit of bodyweight. The aggregate results obtained notably suggests that NOAELH values from Health Canada could be decreased by a factor of 2.6 by the use of the highest 99th percentiles for daily inhalation rates found in children; the minute ventilation rate of 20.83 L/min approximated based on an 8-hour workday may be considered as being conservative; however, the use of the daily inhalation rate of 0.286 m³/kg-day (i.e. 20 m³/day for a 70-kg adult) is inappropriate in risk assessment and management when applied to the whole population.

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