Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 76-78.

Typescript. Includes vita and abstract. Includes bibliographical references (leaves 165-174). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.

Thesis (M.S.)--Brigham Young University. Dept. of Exercise Sciences, 2006. / Includes bibliographical references (p. 13-15).

Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 145-152).

Thesis (D.P.E.)--Springfield College, 2005. / Includes bibliographical references. Also available online (PDF file) by a subscription to the set or by purchasing the individual file.

Thesis (Ph. D.)--University of Oregon, 2005. / Includes bibliographical references (leaves 195-207)

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

Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 75-91).

Core temperature (Tc) regulation is fundamental to mammalian survival, since hypothermia (Tc ≤ 35°C) and hyperthermia (Tc ≥ 40°C) are major risk factors for health and wellbeing. The purpose of this thesis was to determine if acetaminophen, an analgesic and antipyretic drug, increased the onset of hypothermia or hyperthermia during passive cold and heat stress, respectively. It was later investigated if acetaminophen induced inhibition of cyclooxygenase mediated these side-effects. In Study 1a, the plasma acetaminophen response to a dose of 20 mg·kg-1 of lean body mass was determined through enzyme linked immunosorbent assay. In Study 1b, the effect of acetaminophen administration on internal temperature (rectal; Tre) during a passive 2-hour mild cold (20°C, 40% relative humidity) exposure was examined. Study 1a showed that the plasma response was homogenous between subjects, reaching peak concentrations between 80-100 minutes (14 ± 4 μg·ml-1). In Study 1b, acetaminophen reduced Tre in all participants compared with baseline, and the average peak reduction was 0.19 ± 0.09°C. In contrast, Tre remained stable when participants ingested a sugar placebo. Study 1 is the first experiment which confirms a hypothermic side-effect of acetaminophen in healthy humans. Study 2 investigated whether acetaminophen augmented the rate of Tre rise during exposure to passive dry (45°C, 30% r.h.) and humid (45°C, 70% r.h.) heat stress for 2-hours and 45-minutes, respectively. This study showed that the rate of Tre rise in the dry (0.005 vs 0.006°C∙min-1) and humid (0.023 vs 0.021 °C∙min-1) conditions were similar between the acetaminophen and placebo trials (p > 0.05). Study 2 is the first experiment which confirms acetaminophen has no meaningful effect on thermoregulation during passive dry or humid heat exposure. Study 3 determined how the hypothermic effect of acetaminophen changes during exposure to a thermoneutral (25°C, 40% r.h.) and cold (10°C, 40% r.h.) environment for 2-hours. In summary, there was no hypothermic effect of acetaminophen in a thermoneutral environment (p > 0.05), whereas Tre fell by 0.40 ± 0.15°C compared with baseline during cold stress (p < 0.05). Compared with the placebo, Tre was ~0.35°C lower at 120 minutes, but was significantly lower from 70-minutes. Study 3 confirmed that there is a relationship between the level of cold stress and magnitude of the hypothermic effect of acetaminophen. Study 4 determined whether ibuprofen (400 mg), a cyclooxygenase inhibitor, reduced Tre during 2-hour passive cold stress (10°C, 40% r.h.) to a level comparable with acetaminophen. Ibuprofen administration did not influence Tre, vastus medialis shivering, or energy expenditure compared with a placebo throughout the cold exposure (p > 0.05). Taken together, this renders it unlikely that cyclooxygenase activity is required for thermogenesis induced by skin cooling. Study 4 provides evidence that acetaminophen induced hypothermia is not exclusively mediated by cyclooxygenase inhibition. In Summary, this series of experiments has shown that acetaminophen has a hypothermic side effect in healthy humans, which is amplified during acute cold stress. Ibuprofen had no such effect on thermoregulation during cold exposure, so it is unlikely that cyclooxygenase inhibition mediates the hypothermic side-effect of acetaminophen.

The impact of thermal stress on psychological performance has been the subject of considerable research attention. However, the effects of heat on performance are poorly understood. The literature yields inconsistent results, reflecting methodological shortcomings in previous research, particularly with regard to the definition of the independent variable. Investigators have focused on heat stress per se to the neglect of the participants' thermal physiological response. In addition, investigators have typically tested small samples, and have relied on a limited range of performance measures of unknown sensitivity. Few theoretical accounts of performance during thermal stress have been proposed, and these are poorly elaborated. The principal aim of this research programme was to elucidate the effects of heat on psychological performance. Emphasis was placed on defining the independent variable in terms of physiological strain. Performance was measured using a comprehensive range of sensitive tasks. In the first and second experiments, an innovative water immersion technique was used to control thermal strain precisely. The principal effect of heat strain observed in these experiments was an increase in the speed of performance, without variation in accuracy. This effect was attributed to an increase in nerve conduction velocity associated with raised body temperature. The duration of immersion in the second experiment was fifty percent longer than that in the first, but little variation in performance with the duration of heat strain was evident. In light of the limited external validity of the immersion experiments, subsequent investigation focused on the effects of more realistic sources of thermal strain. A survey of military personnel indicated that occupational exposure to thermal stress is perceived to impair some cognitive and psychomotor functions. The final experiment measured performance during prolonged exposure to heat stress in a climatic chamber. The results indicate that the performance changes observed in the immersion experiments generalize to conditions involving exposure to more realistic sources of heat strain