No description available.

Saccostomus campestris display sexual disparity in the use of summer daily torpor in response to energy stress. The hypothesis that males may compensate for a limited heterothermic capacity with lower normothermic body temperatures by maintaining lower resting metabolic rates relative to females was tested. Furthermore, the influence of testosterone on torpor incidence in males was investigated. Body temperature (T[b]) and oxygen consumption (VO₂) were measured at various ambient temperatures (Tₐ) and were compared between the sexes under food ad libitum and food restriction treatments. There were no significant differences in T[b] and VO₂ between sexes under food ad libitum treatment. Under food restriction there were pronounced sex differences in the employment of heterothermy. Females defended a lower setpoint T[b] for torpor (ca. 25°C), than males (ca. 29°C), and also employed torpor more frequently than males. Non-torpid males did, however show slight reductions in VO₂ under food restriction. The effect of testosterone on daily torpor was investigated by comparing minimum T[b]and torpor frequency of castrated mice implanted with testosterone-filled (experimental) and saline-filled (control) silastic capsules in response to food ad libitum and food restriction treatments. Testosterone inhibited torpor in males. The majority of control animals employed torpor under both food ad libitum and food restriction diets. It was concluded that although the animals were capable of shallow, summer torpor, it was confined to moderate ambient temperatures and was not used at low Tₐ's where several animals became pathologically hypothermic. Females derive energetic benefits from the use of torpor whereas males may partially compensate for their limited heterothennic capacity by a reduction in resting metabolic rates, accompanied by moderate reductions in body temperature during energetically stressful periods. The difference in the capacity for daily heterothenny between sexes was attributed to differences in their reproductive physiology. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.

No description available.

Bibliography: leaves 162-197. / vii, 216 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / To determine the effects of melatonin on sleepiness and body temperature under conditions that better approximated the endogenous melatonin profile. / Thesis (Ph.D.)--University of Adelaide, Dept. of Obstetrics and Gynaecology, 1998?

Thesis (M.S.)--University of Michigan, 1977.

Thesis (M.S.)--University of Michigan, 1977.

Thesis (M.S.)--University of Michigan, 1977.

Crianças frequentemente realizam atividades físicas em ambientes quentes. O calor pode afetar o desempenho, conforto subjetivo, tolerância ao exercício e ser preocupante para a saúde. Além disso, parece que crianças obesas, comparadas com as magras, apresentam desvantagens ao se exercitarem no calor. Devido à importância do exercício aeróbio para o manejo da obesidade e promoção da saúde, essas diferenças merecem ser elucidadas, principalmente em meninas, devido à escassez de informações. Objetivo: Comparar as respostas termorregulatórias e perceptivas de meninas pré-púberes magras e obesas durante e após uma sessão de exercício, de similar intensidade relativa, em condição ambiental termoneutra e de calor. Métodos: Para a revisão da literatura, foram selecionados artigos com as palavras chaves: thermoregulation, obesity, children, girls, sweating, exercise, heat, hydration e acclimatization. No estudo experimental, vinte e sete meninas ativas e aclimatizadas, alocadas nos grupos magras e obesas conforme a adiposidade (≤ 25% para as magras e  30% para as obesas) medida pelo DXA, participaram do estudo. Elas pedalaram (carga de 55% do VO2pico) e recuperaram (sentadas) por 30 minutos numa condição termoneutra e outra de calor, com água disponível para ser ingerida à vontade. A temperatura retal (Tre), frequência cardíaca (FC), taxa de percepção de esforço (TPE), sensação térmica, conforto térmico e irritabilidade foram avaliados periodicamente. A sudorese foi avaliada, e durante o exercício no calor foi coletada uma amostra de suor para análise da concentração de eletrólitos (Na+, Cl- e K+). Resultados: Revisão — estudos com meninos indicam que os obesos parecem ser prejudicados nas respostas termorregulatórias durante exercício no calor relacionado: prejuízos na dissipação por convecção devido à menor área de superfície corporal (ASC) pela massa corporal; a menor taxa de sudorese, condicionamento físico, tolerância ao exercício e capacidade de aclimatação ao calor; ao maior custo metabólico para locomoção; e prejuízo na dissipação de calor pela maior gordura subcutânea. Não foram encontrados estudos comparando as respostas termorregulatórias de meninas magras e obesas no calor; e os estudos com o sexo feminino apresentam resultados parcialmente contraditórios ao masculino. Experimento — a Tre inicial foi maior nas obesas nas duas sessões (no calor 37,5 ± 0,3 vs. 37,3 ± 0,3 ºC, e na termoneutra 37,6 ± 0,3 vs. 37,3 ± 0,2 ºC; p = 0,03) e se manteve durante o exercício; e a magnitude do aumento foi maior nas magras, sendo que no calor a Tre final ultrapassou a das obesas (37,8 ± 0,2 vs. 38,0 ± 0,2 ºC; p = 0,04). As magras relataram diminuição do conforto térmico (p = 0,009) e aumento da irritação (p = 0,02) no decorrer do exercício. A FC, respostas perceptivas de TPE e sensação térmica foram semelhantes entre os grupos, assim como as respostas de sudorese. Observou-se maior concentração de Na+ no suor nas obesas (78,7 ± 47,5 vs. 50,5 ± 12,1 mEql-1; p = 0,04). Conclusão: Meninas obesas apresentaram maior Tre inicial, e as magras apresentaram uma maior magnitude de aumento na Tre, principalmente no calor, acompanhada de maior desconforto térmico e irritabilidade. / Children often perform physical activities in hot environments. The heat can affect performance, subjective comfort, exercise tolerance and cause concern for health. Moreover, it seems that obese children, compared with the lean, have disadvantages while exercising in the heat. Given the importance of aerobic exercise for obesity management and health promotion, these differences should be elucidated, especially in girls due to the information lack. Aim: To compare the thermoregulatory responses and perceptual between lean and obese pre-pubertal girls during and after an exercise session, at similar relative effort intensity in the thermoneutral environmental and heat. Methods: For the literature review, articles were selected using the keywords: thermoregulation, obesity, children, girls, sweating, exercise, heat, hydration and acclimatization. In the experimental trial, twenty-seven active and acclimatized girls, placed in groups lean and obese according to fat percentage (≤ 25% for lean and  30% for the obese) measured by DXA, participated in this study. They cycled (charge 55% of VO2peak) and recovered (seated) for 30 minutes in a thermoneutral condition and in the heat, with hydration ad libitum. Rectal temperature (Tre), heart rate (HR), rate of perceived exertion (RPE), thermal sensation, thermal comfort and irritability were assessed periodically. Sweating was evaluated, and during exercise in the heat a sample sweat was collected to electrolytes concentration (Na+, Cl- and K+) analysis. Results: Review — obese children appear to be impaired in thermoregulatory responses during exercise in the heat related to: the convection damage dissipation due to less body surface area (BSA) by body mass, the lower sweating rate, fitness, exercise tolerance and to heat acclimation ability, the higher locomotion metabolic cost, and heat dissipation loss for greater subcutaneous fat. Any study had compared the thermoregulatory responses between lean and obese girls in heat. Trial — the initial Tre was higher in obese in both sessions (in the heat 37.5 ± 0.3 vs 37.3 ± 0.3 ºC and in thermoneutral 37.6 ± 0.3 vs. 37.3 ± 0 2 º C, p = 0.03) and was maintained during exercise, and magnitude of the increase was greater in lean, mainly in the heat when the final Tre surpassed the obese (37.8 ± 0.2 vs. 38.0 ±0.2 ºC, p = 0.04). The thermal comfort has decreased (p = 0.009) and irritation has increased (p = 0.02) in the lean during the exercise. HR, sweating responses and perceptual responses of TPE and thermal sensation were similar between groups. A higher concentration of Na+ in sweat was observed in obese (78.7 ± 47.5 vs 50.5 ± 12.1 mEql-1, p = 0.04). Conclusion: Initial Tre were higher in obese group, and lean had a greater magnitude of increase in Tre, especially during exercise in the heat, accompanied by thermal discomfort and irritability increased.

Made available in DSpace on 2014-06-11T19:28:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-29Bitstream added on 2014-06-13T18:32:41Z : No. of bitstreams: 1 moyses_am_me_botfm.pdf: 269523 bytes, checksum: 3d9ad3ef9b24efec08c580d656c6efdc (MD5) / Comparar a eficiência dos dispositivos manta e colchão térmicos na manutenção da normotermia em pacientes nos períodos intra e pósoperatório; Analisar o período de tempo da recuperação pós-anestésica, com o uso dos dispositivos manta e colchão térmicos; relacionar a utilização dos dispositivos manta e colchão térmicos às variáveis: idade, índice de massa corpórea (IMC) e porte cirúrgico. Trata-se de estudo transversal, prospectivo, randomizado, de delineamento quantitativo, realizado na unidade de Centro Cirúrgico do Hospital das Clínicas de Botucatu, de janeiro a outubro de 2011. Participaram da pesquisa 38 pacientes que foram divididos em 2 grupos (G1 e G2), sendo ambos compostos por 19 pacientes. G1 utilizou a manta térmica com sistema de aquecimento Bair Hugger® modelo 750, sendo esta posicionada nos membros inferiores. G2 utilizou o colchão térmico com circulação de ar quente KanMedo WarmCloudTM. Inicialmente o colchão foi posicionado sobre a mesa cirúrgica a uma temperatura 37oC e insuflado, em seguida os pacientes foram posicionados em decúbito dorsal horizontal, em contato direto com o colchão. Para a coleta dos dados utilizou-se instrumento confeccionado pelo pesquisador, composto por 4 itens: caracterização do paciente, fatores relacionados ao procedimento cirúrgico, aspectos relacionados à recuperação pós-anestésica e tempo de internação. O tempo cirúrgico foi maior no grupo G2 (p=0,03), porém, não se observou aumento na incidência de hipotermia neste grupo; no G2 evidenciou-se uma tendência a menor tempo de recuperação pós-anestésica (p=0,06). A infusão de amido no intraoperatório do G2 foi maior (p=0,03), porém, não influenciou na ocorrência de hipotermia. No G2 a temperatura axilar foi maior aos 120 minutos do inicio do procedimento anestésico cirúrgico... / surgical outcomes, and increased patient satisfaction. The use of perioperative forced-air warming devices is one way of preventing inadvertent hypothermia. There is scant evidence, however, on the best warming method or the acceptability of these methods to patients. The present study aimed to compare two forced-air warming devices to maintain perioperative normothermia: blanket versus mattress. Information was obtained from 38 patients underwent gastrointestinal surgical procedures. Skin and esophageal temperatures were compared for patients who were warmed with a warming blanket (Bair Hugger®), placed over the lower extremities (G1), versus patients who were warmed with a warming mattress (KanMedo WarmCloudTM) placed under the patient’s body (G2). In addition to the temperature evaluation, length of the surgical procedure, total volume of intraoperative fluid replacement, and length of stay in the Post Anesthetic Care Unit (PACU) were also recorded. Although the length of surgery was longer in G2 (291.6±115.2 versus 214.6±91.1 minutes; p=0.03), there was no increase in the hypothermia incidence in this group. Skin temperature was higher at 120 minutes after anesthesia induction in G2 (35.3±0.9 versus 34.8±0.8; p=0.04). Esophageal temperature was also higher in G2 at 120 and at 180 minutes after anesthesia induction, as well as, at the end of the surgery (36.1±0.7 versus 35.4±0.6, p <0.001; 35.9±0.7 versus 35.3±0.7, p=0.03; and 36.1±0.7 versus 35.2±0.9, p<0.001 respectively). Although the patients in G2 had 30 minutes shorter length of stay in the PACU, there was no statistically significant difference between the two groups (115.4±47.3 versus 82.5±53.1 minutes; p=0.06). The infused volume of Hetarstarch was higher in G2 when compared with G1 (730.8±259.4 versus 541.7±144.3; p=0.03)... (Complete abstract click electronic access below)

O presente estudo teve como objetivo verificar a existência da melhoria de aderência no modelo normalizado de conforto térmico (PMV), utilizando as taxas metabólicas a partir das sensações térmicas reais de usuários em ambientes industriais. Assim, o estudo determinou a taxa metabólica através de análise de regressão múltipla e pela substituição dos valores de PMV pelas sensações térmicas reais através do software específico de conforto térmico em concordância com a norma ISO 7730 de 2005 obtendo assim a taxa metabólica calculada. Com isso foram calculados novos valores de PMV utilizando os valores das taxas metabólicas, resultando em PMVtab, PMV1 e PMV2. Para verificar qual dos valores de taxa metabólica aproximou-se ao modelo PMV com sensação térmica real, foi realizada uma análise de regressão simples, obtendo-se duas equações para correção da taxa metabólica tabelada. Para verificar a validade das equações da taxa metabólica corrigida, foi procedido o cálculo do PMV em um conjunto de 30 medições. O resultado obtido para o PMV tabelado foi de R2=0,25; para o PMV corrigido, 1, R2=0,26; para o PMV corrigido 2, de R2=0,11. Isso demonstra que não houve correlação entre as sensações térmicas relatas pelos trabalhadores e os valores de PMV tabelados e corrigidos. O percentual de diferença entre o Mtabelado e o Mcorrigido 1 e Mcorrigido 2 foi na ordem de 1,66% e -0,40% respectivamente. Considera-se que para este estudo, em um conjunto de 30 medições, levando em consideração a sensação térmica real dos trabalhadores, os valores da taxa metabólica tabelada não apresentaram boa precisão, quando comparados aos valores do PMV e à sensação térmica real. Porém, pode-se considerar que se o objetivo for promover uma correção na taxa metabólica tabelada, deve-se aplicar sobre a mesma um percentual de acréscimo de 1,66%. / This research aimed to verify the presence of adhesion increase in the normalized standard of thermal comfort (PMV) by using metabolic rates from users’ actual thermal sensations in industrial environments. So, this research defined the metabolic rate by multiple regression analysis, and by substituting the values of PMV by actual thermal sensations through the specific software of thermal comfort according to ISO 7730, 2005, thus getting the metabolic estimated rate. With that, new PMV values were calculated by using the values of metabolic rates, resulting in PMVtab, and PMV1 PMV2. To check which of the values of metabolic rate approached the PMV model with actual thermal sensation, an analysis of simple regression was performed, obtaining two equations for the correction of the metabolic rate table. To check the equation validity of the corrected metabolic rate, the calculation of PMV in a set of 30 measurements was carried on. The obtained result for the tabulated PMV was of R2 = 0.25; for the PMV corrected 1, of R2 = 0.26; for the PMV corrected 2, of R2 = 0.11. It demonstrates that there was no correlation between the thermal sensations which had been reported by the workers and the tabulated and corrected values of PMV. The percentage difference between Mtabulated and Mcorrected 1 and Mcorrected 2 was of 1.66% and -0.40% respectively. It is considered that for this study, in a set of 30 measurements, taking into account the workers’ actual thermal sensation, the values of the tabulated metabolic rate are not well accurate when compared to the values of PMV and to the actual thermal sensation. However, it may be considered that if the aim is to promote a small correction in the tabulated metabolic rate, one should apply on it an increasing percentage of 1.66 %.