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Human Thermal ComfortHuynh, Kien Khanh 12 May 2001 (has links)
The purpose of this research is to investigate human comfort criteria under steady-state conditions as a function of ambient air temperature, mean radiant temperature, relative humidity, air velocity, level of activity, and clothing insulation. Since the current ASHRAE Standard 55-1994 is for sedentary activity, this study will consider relative humidity (20% to 65%), dry bulb temperature (73 oF to 82 oF), air velocity (30 fpm and 50 fpm), and sedentary-to-moderate activity. The mean radiant temperature will be taken to be the same as the ambient air temperature. The experimental results collected at the Kansas State University Environmental Test Chamber are compared with the Fanger (1982) thermal comfort model and with ASHRAE Standard 55-1994. The experimental study results agreed well with ASHARE Standard 55-1994 for 1-met activity level (sedentary), and the thermal comfort for 1-met activity level was predicted with reasonable accuracy by Fanger?s (1982) Model. For 2.3 met activity level, the experimental results did not agree with ASHRAE Standard 55-1994 or the Fanger Model predictions.
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Central fatigue during exercise : potential manipulations and limiting factorsHobson, Ruth M. January 2010 (has links)
The development of fatigue has been an area of interest to athletes and scientists alike for many years. Often, particularly during prolonged exercise in the heat, there is no obvious peripheral reason for fatigue and the central nervous system is cited as the source. The mechanisms and potential manipulations of this fatigue remain largely unclear. Chapters Three and Four attempted to reduce the transport of the serotonin precursor tryptophan into the brain in order to reduce or delay serotonin synthesis and therefore increase exercise capacity. In Chapter Three branched-chain amino acid drinks were fed before and during prolonged cycling to exhaustion in the heat on two occasions and control drinks were fed on two other occasions. There was no effect of the branched-chain amino acids on exercise capacity and the intra-individual variability in seven of the eight participants was small. One participant did appear to cycle for longer on the branched-chain amino acid trials compared to the control trials. In Chapter Four a 104 g bolus of amino acids, designed to deplete plasma tryptophan concentration, was fed seven hours before a prolonged cycle to exhaustion in the heat. There was no difference in exercise capacity between the tryptophan depletion trial and the control trial in which tryptophan was also ingested. These findings suggest that the delivery of tryptophan to the central nervous system is not the only factor influencing the onset of fatigue. The investigation undertaken in Chapter Five looked at the serotonin transporter density on the blood platelets of current and retired international level athletes competing in either endurance or sprint running events and a sedentary control group. Using the platelet as an accessible and reliable model for the serotonergic neuron, the maximum number of binding sites was assessed using the radio-labelled serotonin reuptake inhibitor [3H]Paroxetine. Those currently training for endurance events had a greater number of binding sites than any of the other groups. This supports previous findings and suggests that endurance training can increase the number of serotonin transporters on blood platelet membranes. During resting heat exposure in Chapter Six, the application of a 1 % menthol solution to the skin of the forearms, back and forehead elicited a warming sensation in some individuals and a cooling sensation in other individuals, but never any change in skin or core temperature nor skin blood flow. A small proportion of individuals did not perceive any change in skin thermal sensation. Chapter Seven applied these findings to a pre-loaded twenty minute exercise performance test in the heat. It was hypothesised that those who perceived a warming effect may perform worse when a menthol solution was applied compared to a control solution and conversely, those who perceived a cooling sensation may perform better with a menthol solution than with a control solution. There was no difference in exercise performance between those who felt a warming sensation and those who felt a cooling sensation. Those who felt a warming sensation felt significantly warmer on the menthol trial than the control trial but this did not affect their performance. However, those who reported a cooling sensation tended to feel cooler on the menthol trial than the control trial, and there was a tendency for an improvement in performance on the menthol trial compared to the control trial. Due to the experimental protocols adopted in this thesis it was possible to assess the reliability of an exercise capacity test compared to an exercise performance test. Chapter Three showed a coefficient of variation of 11.0 ± 11.2 % and Chapter Four showed a 11.5 ± 12.4 % variability for exercise capacity tests. Chapter Seven showed a coefficient of variation in a pre-loaded time-trial exercise performance test of 3.9 ± 9.6 % suggesting that an exercise performance test may be more reliable than an exercise capacity test. However, the aims of an investigation are still likely to be the main factor influencing the choice of protocol. It seems likely that no single mechanism will be responsible for the cessation of exercise. The investigations undertaken in this thesis also highlight many avenues for future exploration.
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Thermal comfort on train journeysKelly, Lisa K. January 2011 (has links)
This thesis presents a body of work conducted to determine thermal comfort on train journeys. Relatively little research has been conducted on trains in comparison with the vast body of work conducted within building environments. This thesis aimed to expand our knowledge of rail passenger thermal comfort throughout the journey; platform to destination. The train journey was separated into its component parts and analysed by conducting both laboratory and field experiments that either simulated or measured aspects of a train journey. Laboratory experiment 1 examined appropriate methods of data collection during train journeys. Participants (9 males and 9 females) were exposed to a simulated train environment three times and used a different data collection method on each occasion; a paper-based method, a voice recorder or a Personal Digital Assistant (PDA). Results concluded that the three methods can be used interchangeably when recording thermal comfort data. Participants preferred the PDA over the other two methods because they felt it afforded them a level of privacy in addition to blending in with other rail passengers using similar technologies. The second laboratory experiment measured thermal comfort following a change of environment. Participants (12 males and 12 females) were exposed to three environmental conditions (warm, neutral and slightly cool) in a thermal chamber on three separate occasions. The exposure lasted 30 minutes, after which, participants entered a new environment that was the same on each occasion (slightly cool). Results showed that overshoots in sensation (beyond those predicted by the Predicted Mean Vote thermal comfort index PMV) are observed following downward steps (warmer to cooler) in environmental conditions. No overshoots were observed following the upward step (cooler to warmer) in environment, with sensations immediately reflecting the predicted steady-state values. Laboratory experiment 3 (22 males and 26 females) expanded the research conducted in laboratory experiment 2 by exposing participants to greater magnitudes of environmental change. In addition, sensation was measured after this change until steady-state was reached. Participants were exposed to four environmental conditions (cool to warm to neutral to cool or cool to cold to warm to cool) consecutively over a 2 hour period with 30 minutes spent in each location. Results demonstrated similar effects to those observed during laboratory experiment 2 with overshoots observed following downward steps in environmental conditions and none observed in the opposite direction. Sensations demonstrating overshoots gradually increased until steady-state was achieved after approximately 25 minutes. Field experiment 1 (12 males and 32 females) measured thermal comfort while boarding trains. Participants were taken on a short train journey and recorded sensations whilst on the platform and during boarding. Results showed that overshoots may also be observed following step up and step down in environments. It is hypothesised that change in air velocity is influential in this effect. Thermal comfort throughout a train journey was measured in field experiment 2. Participants (16 males and 16 females) reported on thermal comfort on the platform, during boarding and throughout a return train journey from Loughborough to London St Pancras. Results also demonstrated overshoots following upward transients indicating that there are factors in the field that do not occur in laboratory conditions. Subjective parameters reach steady-state after approximately 20 minutes and PMV accurately predicted sensations during the journey. Again, air velocities may have interacted with other variables resulting in the overshoots following upward steps in environmental conditions. Laboratory experiments 2 and 3 resulted in the creation of a model predicting sensation following a change of environment, PMVTRANS. When the model was compared with the field data, it could not accurately predict sensations observed during transients. It also could not predict the sensation overshoots observed following upward transients. A new model is now proposed, NEW PMVTRANS. This model shows greater correlation with actual sensation than PMV; however it does require further validation from field data. Research has shown that PMV is an accurate estimator of sensation within a train carriage and should be used by train designers to optimise the environmental conditions for passengers.
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Análise da sensação do conforto térmico nos verões do Rio Grande do Sul entre 2006 e 2014Baldasso, Tais Bavaresco January 2016 (has links)
No verão do Rio Grande do Sul (RS) são frequentes os registros de temperatura do ar acima de 30°C por alguns dias consecutivos, o que gera um fenômeno denominado de ondas de calor que associadas à atuação da massa de ar tropical continental, afetam o conforto térmico e o bem-estar das pessoas. Essa constante troca de massas de ar ocasiona extremos de temperatura e interfere no conforto térmico. Os estudos sobre o conforto térmico usando dados horários no RS são raros, e, portanto, são desconhecidas as diferentes condições térmicas para a sensação do conforto. O presente estudo analisou a sensação de conforto térmico e sua variabilidade para nove municípios do RS empregando o Índice de Temperatura Efetiva (ITE) para os verões de 2006/2007 a 2013/2014. Essa sensação varia no RS de acordo com a região geográfica, onde se identificou três padrões de conforto térmico na análise do ITE máximo e mínimo. Os municípios de menor altitude, como Porto Alegre, Santa Maria e Uruguaiana, são os que mais registraram desconforto térmico. A faixa térmica do calor moderado ocorre com maior frequência no ITE das máximas, seguido pela faixa de calor. A sensação de calor extremo é registrada nesses três municípios. No ITE das mínimas a faixa do confortável é predominante, seguida pela de ligeiramente quente. A maior continentalidade de Santa Maria e Uruguaiana faz com que esses dois municípios sejam os mais quentes do RS. Bento Gonçalves, Caçapava do Sul e Erechim, com altitudes de 623 m, 421 m e 777 m, respectivamente, registram sensação térmica de calor moderado nas máximas de ITE, seguido pela sensação de ligeiramente quente. Já as mínimas correspondem à faixa do confortável e de ligeiramente fresco. Torres e Rio Grande, que são litorâneos e ao nível do mar, tiveram registros na faixa do calor moderado no ITE máximo e de confortável no ITE mínimo. São José dos Ausentes, que apresenta a maior altitude, registrou ITE mais baixo, com índice na faixa do ligeiramente quente nas máximas e de frescor no registro das mínimas. / In summer of Rio Grande do Sul (RS) are frequent air temperature records above 30°C for a few several days, which generates a phenomenon called heat waves associated with the action of the continental tropical air mass, affecting thermal comfort and the well-being of people. This constant exchange of air masses causes extreme temperature events and interferes in the thermal comfort. Studies about thermal comfort using hourly data of RS are rare, and therefore are unknown the different thermal conditions for the sensation of thermal comfort. This study analyzed the sensation of thermal comfort and variability for nine municipalities in the RS using the Effective Temperature Index (ETI) for the summers of 2006/2007 to 2013/2014. This sensation varies in RS according to the geographical region, where it was identified three patterns of thermal comfort in the analysis of maximum and minimum ETI. The municipalities with the lowest altitude, in Porto Alegre, Santa Maria and Uruguaiana, are the most recorded thermal discomfort. The temperature range of moderate heat occurs most frequently in the maximum ETI, followed by heat range. The sensation of extreme heat have been recorded in these three municipalities. In minimum ETI, the comfortable range is predominant, followed by slightly warm. The continentality effect of Santa Maria and Uruguaiana makes these two cities the hottest places of the RS. Bento Gonçalves, Caçapava do Sul and Erechim, with altitudes of 623 m, 421 m and 777 m, respectively, recorded thermal sensation moderate heat in maximum ETI, followed by sensation slightly warm. Already the minimum correspond to the comfortable and slightly cool range. Torres and Rio Grande, which are coastal places at the sea level, had records in the range of moderate heat maximum ETI and comfortable minimum ETI. São José dos Ausentes, with the highest altitude, recorded lower ETI, with index in the range of slightly warm at maximum freshness in the record minimum.
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Uticaj parametara mikroklime, buke i osvetljenja na toplotni komfor u radnoj sredini / Influence of parameters of microclimate, noise and lighting on thermalcomfort in the working environmentBojić Žarko 24 September 2018 (has links)
<p>U radu se proučava uticaj parametara mikroklime, buke i osvetljenja<br />na toplotni osećaj i toplotni komfor u radnoj sredini. Između čoveka<br />i njegovog okruženja postoji stalna interakcija, koja može uzrokovati<br />fiziološke poremećaje u organizmu. U okviru rada, prikazane su<br />teorijske osnove parametara mikroklime, buke i osvetljenja, kao i<br />njihov teorijski uticaj na generisanje i razmentu toplotne energije<br />između čoveka i okoline. Rad obuhvata istraživanje međuzavisnosti<br />proučavanih parametara, toplotnog osećaja i toplotnog komfora<br />čoveka na radnom mestu u poziciji stajanja.</p> / <p>This paper examines the influence of the parameters of microclimate, noise<br />and lighting on the thermal sensation and thermal comfort in the working<br />environment. There is a constant interaction between a person and his<br />environment, which can cause physiological disorders in the organism. In the<br />framework of this paper, the theoretical bases of the parameters of<br />microclimate, noise and lighting, as well as their theoretical influence on the<br />generation and exchange of heat energy between person and environment<br />are presented. The paper encompasses research on the interdependence of<br />the parameters studied for thermal sensation and the thermal comfort of a<br />person at the workplace in a standing position.</p>
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Análise da sensação do conforto térmico nos verões do Rio Grande do Sul entre 2006 e 2014Baldasso, Tais Bavaresco January 2016 (has links)
No verão do Rio Grande do Sul (RS) são frequentes os registros de temperatura do ar acima de 30°C por alguns dias consecutivos, o que gera um fenômeno denominado de ondas de calor que associadas à atuação da massa de ar tropical continental, afetam o conforto térmico e o bem-estar das pessoas. Essa constante troca de massas de ar ocasiona extremos de temperatura e interfere no conforto térmico. Os estudos sobre o conforto térmico usando dados horários no RS são raros, e, portanto, são desconhecidas as diferentes condições térmicas para a sensação do conforto. O presente estudo analisou a sensação de conforto térmico e sua variabilidade para nove municípios do RS empregando o Índice de Temperatura Efetiva (ITE) para os verões de 2006/2007 a 2013/2014. Essa sensação varia no RS de acordo com a região geográfica, onde se identificou três padrões de conforto térmico na análise do ITE máximo e mínimo. Os municípios de menor altitude, como Porto Alegre, Santa Maria e Uruguaiana, são os que mais registraram desconforto térmico. A faixa térmica do calor moderado ocorre com maior frequência no ITE das máximas, seguido pela faixa de calor. A sensação de calor extremo é registrada nesses três municípios. No ITE das mínimas a faixa do confortável é predominante, seguida pela de ligeiramente quente. A maior continentalidade de Santa Maria e Uruguaiana faz com que esses dois municípios sejam os mais quentes do RS. Bento Gonçalves, Caçapava do Sul e Erechim, com altitudes de 623 m, 421 m e 777 m, respectivamente, registram sensação térmica de calor moderado nas máximas de ITE, seguido pela sensação de ligeiramente quente. Já as mínimas correspondem à faixa do confortável e de ligeiramente fresco. Torres e Rio Grande, que são litorâneos e ao nível do mar, tiveram registros na faixa do calor moderado no ITE máximo e de confortável no ITE mínimo. São José dos Ausentes, que apresenta a maior altitude, registrou ITE mais baixo, com índice na faixa do ligeiramente quente nas máximas e de frescor no registro das mínimas. / In summer of Rio Grande do Sul (RS) are frequent air temperature records above 30°C for a few several days, which generates a phenomenon called heat waves associated with the action of the continental tropical air mass, affecting thermal comfort and the well-being of people. This constant exchange of air masses causes extreme temperature events and interferes in the thermal comfort. Studies about thermal comfort using hourly data of RS are rare, and therefore are unknown the different thermal conditions for the sensation of thermal comfort. This study analyzed the sensation of thermal comfort and variability for nine municipalities in the RS using the Effective Temperature Index (ETI) for the summers of 2006/2007 to 2013/2014. This sensation varies in RS according to the geographical region, where it was identified three patterns of thermal comfort in the analysis of maximum and minimum ETI. The municipalities with the lowest altitude, in Porto Alegre, Santa Maria and Uruguaiana, are the most recorded thermal discomfort. The temperature range of moderate heat occurs most frequently in the maximum ETI, followed by heat range. The sensation of extreme heat have been recorded in these three municipalities. In minimum ETI, the comfortable range is predominant, followed by slightly warm. The continentality effect of Santa Maria and Uruguaiana makes these two cities the hottest places of the RS. Bento Gonçalves, Caçapava do Sul and Erechim, with altitudes of 623 m, 421 m and 777 m, respectively, recorded thermal sensation moderate heat in maximum ETI, followed by sensation slightly warm. Already the minimum correspond to the comfortable and slightly cool range. Torres and Rio Grande, which are coastal places at the sea level, had records in the range of moderate heat maximum ETI and comfortable minimum ETI. São José dos Ausentes, with the highest altitude, recorded lower ETI, with index in the range of slightly warm at maximum freshness in the record minimum.
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Percepção térmica de idosos / Thermal perception of the elderlyMontanheiro, Fabiana Padilha [UNESP] 03 March 2016 (has links)
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Previous issue date: 2016-03-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No panorama mundial o número de pessoas com 60 anos ou mais vem aumentando rapidamente. A grande maioria dos idosos que vive de forma independente deseja continuar seu estilo de vida atual, e para isso precisa de apoio extra e orientação para envelhecer com bem-estar e saúde. Essas condições incluem a convivência em ambientes agradáveis, inclusive em relação ao conforto térmico. Neste contexto, este trabalho avaliou a sensação térmica de idosos, comparando-a com os resultados do índice PMV (Voto Médio Estimado: Predicted Mean Vote) de Fanger. Foi realizada uma pesquisa exploratória de abordagem qualitativa (questionários) e quantitativa (medições com termômetros de bulbo seco, bulbo úmido e de globo), conforme a norma ISO 7730:2006; 2011, em três instituições que oferecem serviços de atividades específicas para a faixa populacional na cidade de Bauru (SP): o SESI (Serviço Social da Indústria), o SESC (Serviço Social do Comércio) e a AAPIBR (Associação dos aposentados, pensionistas e idosos de Bauru e Região). Os resultados obtidos demonstraram que as sensações térmicas reais (STR) relatadas pelos idosos (sensações subjetivas) são estatisticamente similares às calculadas pela equação do PMV (sensações analíticas) para três faixas desse índice: -1, 0 e 1. / In the global landscape, the number of people aged 60 and over is increasing rapidly. The vast majority of seniors who live independently wish to continue their current lifestyle, and for that they need extra support and guidance to grow old with wellness and health. These conditions include living in pleasant environments, including thermal comfort. In this context, this study evaluated the thermal sensation of the elderly, comparing it with the results from the PMV (Predicted Mean Vote) method (Fanger). An exploratory research with qualitative (questionnaires) and quantitative approach (measured with dry-bulb, wet-bulb and globe thermometers) was performed according to ISO 7730: 2006; 2011, in three institutions that offer specific activities services for the population group in the city of Bauru (São Paulo state): SESI (Industrial Social Services), SESC (Commercial Social Services) and AAPIBR (Association of retirees, pensioners and seniors of Bauru and region). The results showed that the actual thermal sensations (ATS) reported by the elderly (subjective sensations) are statistically similar to those calculated by the PMV equation (analytical sensations) on a threepoint scale: -1, 0 and 1. / MCA 162174
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Conforto térmico em espaços abertos: estudo de caso em um Parque Urbano na cidade de João Pessoa-PBLima, Linccon de Carvalho 30 September 2016 (has links)
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Previous issue date: 2016-09-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Studies of thermal comfort in climatic chambers have the limitation of disregarding the user's adaptation to the environmental conditions. In order to overcome limitations of currentelly thermal comfort models, new investigations has been conducted to identify the thermal comfort in open spaces or free running buildings. Inserted in this context, this study has as general objective to evaluate the thermal sensation of the visitors of an urban park (Bica) in João Pessoa-PB, a city of hot and humid weather climate in Northeastern Brazil. As methodology, we used microclimatic monitoring of the variables: air temperature, globe temperature, humidity, wind speed and solar radiation. Questionnaires were also applied to visitors to assess the feeling of thermal comfort within the park. The microclimatic data were collected with the aid of a portable meteorological station DAVIS and a thermal stress meter - TGD300. To carry out the statistical analyzes was used the STATISTIC 7.0 program. Through statistical analysis it was possible to identify a comfort range between 23-31°C. The logistic regression model showed that three climate variables (air temperature, wind speed and mean radiant temperature) have significant effect on the thermal sensation vote felt by respondents. When the thermal sensation vote was compared to the PMV/PPD index, it was verified in loco was always in a lower category to the PMV. The results found in this research can help in planning the city in the search for a more banlanced urban environmrt, rspecially with regard to thermal confort. / Estudos de conforto térmico em câmara climatizada apresentam a limitação de desconsiderar a adaptação do indivíduo às condições ambientais. Com objetivo de superar limitações dos modelos atuais de conforto térmico, pesquisas têm sido realizadas para identificar os limites de conforto em ambientes sem climatização e em condições naturais, dentre elas, destacam-se os estudos de conforto em espaços abertos. Inserido nesse contexto este estudo tem como objetivo geral avaliar a sensação térmica dos visitantes de um parque urbano (Bica) em João Pessoa-PB, uma cidade de clima quente e úmido no nordeste do Brasil. Como metodologia utilizou-se de monitoramento microclimático das variáveis: temperatura do ar, temperatura do globo, umidade, velocidade do vento e radiação solar. Também foram aplicados questionários aos visitantes a fim de avaliar a sensação de conforto térmico dentro do parque. Os dados microclimáticos foram coletados com auxilio de uma mine estação meteorológica portátil DAVIS e um medidor de stress térmico- TGD300. Para realizar as análises estatísticas foi utilizado o programa STATISTIC 7.0. Através da análise estatística foi possível identificar um intervalo de conforto de 23° a 31°C, o modelo de regressão logística mostrou que três variáveis climáticas (temperatura do ar, velocidade do vento, temperatura radiante média) têm influência sobre o voto de sensação térmica dos entrevistados. Quando o voto de sensação térmica foi comparado com o índice de conforto PMV/PPD observaram-se diferenças significativas entre as duas variáveis, a sensação térmica verificada in loco esteve sempre em uma categoria inferior ao PMV. Os resultados encontrados nesta pesquisa podem auxiliar ao planejamento da cidade na busca por um ambiente urbano mais equilibrado especialmente no que se refere ao conforto térmico.
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Análise da sensação do conforto térmico nos verões do Rio Grande do Sul entre 2006 e 2014Baldasso, Tais Bavaresco January 2016 (has links)
No verão do Rio Grande do Sul (RS) são frequentes os registros de temperatura do ar acima de 30°C por alguns dias consecutivos, o que gera um fenômeno denominado de ondas de calor que associadas à atuação da massa de ar tropical continental, afetam o conforto térmico e o bem-estar das pessoas. Essa constante troca de massas de ar ocasiona extremos de temperatura e interfere no conforto térmico. Os estudos sobre o conforto térmico usando dados horários no RS são raros, e, portanto, são desconhecidas as diferentes condições térmicas para a sensação do conforto. O presente estudo analisou a sensação de conforto térmico e sua variabilidade para nove municípios do RS empregando o Índice de Temperatura Efetiva (ITE) para os verões de 2006/2007 a 2013/2014. Essa sensação varia no RS de acordo com a região geográfica, onde se identificou três padrões de conforto térmico na análise do ITE máximo e mínimo. Os municípios de menor altitude, como Porto Alegre, Santa Maria e Uruguaiana, são os que mais registraram desconforto térmico. A faixa térmica do calor moderado ocorre com maior frequência no ITE das máximas, seguido pela faixa de calor. A sensação de calor extremo é registrada nesses três municípios. No ITE das mínimas a faixa do confortável é predominante, seguida pela de ligeiramente quente. A maior continentalidade de Santa Maria e Uruguaiana faz com que esses dois municípios sejam os mais quentes do RS. Bento Gonçalves, Caçapava do Sul e Erechim, com altitudes de 623 m, 421 m e 777 m, respectivamente, registram sensação térmica de calor moderado nas máximas de ITE, seguido pela sensação de ligeiramente quente. Já as mínimas correspondem à faixa do confortável e de ligeiramente fresco. Torres e Rio Grande, que são litorâneos e ao nível do mar, tiveram registros na faixa do calor moderado no ITE máximo e de confortável no ITE mínimo. São José dos Ausentes, que apresenta a maior altitude, registrou ITE mais baixo, com índice na faixa do ligeiramente quente nas máximas e de frescor no registro das mínimas. / In summer of Rio Grande do Sul (RS) are frequent air temperature records above 30°C for a few several days, which generates a phenomenon called heat waves associated with the action of the continental tropical air mass, affecting thermal comfort and the well-being of people. This constant exchange of air masses causes extreme temperature events and interferes in the thermal comfort. Studies about thermal comfort using hourly data of RS are rare, and therefore are unknown the different thermal conditions for the sensation of thermal comfort. This study analyzed the sensation of thermal comfort and variability for nine municipalities in the RS using the Effective Temperature Index (ETI) for the summers of 2006/2007 to 2013/2014. This sensation varies in RS according to the geographical region, where it was identified three patterns of thermal comfort in the analysis of maximum and minimum ETI. The municipalities with the lowest altitude, in Porto Alegre, Santa Maria and Uruguaiana, are the most recorded thermal discomfort. The temperature range of moderate heat occurs most frequently in the maximum ETI, followed by heat range. The sensation of extreme heat have been recorded in these three municipalities. In minimum ETI, the comfortable range is predominant, followed by slightly warm. The continentality effect of Santa Maria and Uruguaiana makes these two cities the hottest places of the RS. Bento Gonçalves, Caçapava do Sul and Erechim, with altitudes of 623 m, 421 m and 777 m, respectively, recorded thermal sensation moderate heat in maximum ETI, followed by sensation slightly warm. Already the minimum correspond to the comfortable and slightly cool range. Torres and Rio Grande, which are coastal places at the sea level, had records in the range of moderate heat maximum ETI and comfortable minimum ETI. São José dos Ausentes, with the highest altitude, recorded lower ETI, with index in the range of slightly warm at maximum freshness in the record minimum.
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Thermal, circulatory, and neuromuscular responses to whole-body cryotherapyWesterlund, T. (Tarja) 17 March 2009 (has links)
Abstract
The purpose of this study was to examine thermal (body temperature, thermal sensation and comfort ratings), circulatory (blood pressure, heart rate variability) and neuromuscular performance responses to whole-body cryotherapy (WBC, -110 °C).
Altogether 66 healthy subjects were exposed to WBC for two minutes. The acute and long-term changes were examined, when the subjects were exposed to WBC three times a week during three months.
Skin temperatures decreased very rapidly during WBC, but remained such a high level that there was no risk for frostbites. The effects on rectal temperature were minimal. Repeated exposures to WBC were mostly well tolerated and comfortable and the subjects became habituated at an early stage of trials. WBC increased both systolic (24 mmHg) and diastolic (5 mmHg) blood pressures temporarily. Adaptation of blood pressure was not found during three months. The acute cooling-related increase in high-frequency power of RR-intervals indicated an increase in cardiac parasympathetic modulation, but after repeated WBC the increase was attenuated. The repeated WBC exposure-related increase in resting low frequency power of RR-intervals resembles the response observed related to exercise training. There are signs of neuromuscular adaptation, especially in dynamic performance. A single WBC decreased flight time in drop-jump exercise, but after repeated WBC these changes were almost vanished. This adaptation was confirmed by the change of the activity of the agonist muscle, which increased more and the change of the activity of antagonist muscle, which increased less/did not change after repeated WBC indicating reduced co-contraction and thus, neuromuscular adaptation.
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