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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.
11

Effects of warm foot bathing on distal-proximal skin temperature gradient, PSG sleep and perceived sleep quality in older adults with sleep disturbance /

Liao, Wen-Chun. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 56-68).
12

The effect of pressure duration on sacral skin blood flow and sacral skin temperature in healthy adults and patients with either spinal cord injury or orthopedic trauma /

Sae-Sia, Wipa, January 2005 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 2005. / "May, 2005." Typescript. Vita. Includes bibliographical references (leaves 217-243). Also issued on the Internet.
13

The initial perception of humidity

Newton, Mark K. January 2011 (has links)
No description available.
14

Cold protecting emollients and frostbite

Lehmuskallio, E. (Eero) 21 May 2001 (has links)
Abstract Frostbite of the face and ears is a common problem in cold winters. Application of an emollient on the face is a traditional way to prevent frostbite in Finland. The preliminary results of an epidemiological study on frostbite in Finnish conscripts unexpectedly showed that the use of cold protecting emollients increased the risk of facial frostbite. This finding motivated studies on the effects and use of cold protecting emollients. 830 male Finnish conscripts answered a questionnaire concerning the use of cold protecting emollients, subjective experience of using them in cold and cumulative incidence of frostbite in the ears and face. Risk factors of frostbite were investigated in a prospective epidemiological study including 913 Finnish conscripts needing medical attention for frostbite of the ears or face and their 2478 matched, uninjured controls. Thermal properties of four different emollients were studied in vitro with a skin model and in vivo in experimental cold exposures of test persons. Test emollient was applied on one half of the face, as the other half acted as control. The skin temperatures of the face-halves were compared symmetrically by thermistors and infrared thermography. Subjective sensation of thermal half-difference was also registered. 21% of the conscripts had used emollients in the cold, a majority with an experience of protection. 47% of the conscripts had had frostbite in the head (42% in the ears and 23% on the face). There was a statistically significant correlation between the use of emollients and the incidence of facial frostbite in both epidemiological studies. Applying protective emollients formed an independent risk factor for frostbite of the cheeks, nose and ear lobes (odds ratios 3.3-5.6). The thermal insulation of test emollients on the skin model was minimal. On living skin, the applied half was somewhat cooler in a majority of comparisons. However, white petrolatum gave often a subjective perception of a warming effect. False sensation of safety may form the principal cause for the increased risk of frostbite associated with the use of emollients. When the warning symptoms of cold are weak, necessary protective measures are not carried out.
15

Immune and Endocrine System Responses to Acute Skin-Temperature Reductions and Thermal Biofeedback

Bell, Kenneth E. 01 May 1994 (has links)
The purpose of this study was to examine the effects of the cold pressor test on skin temperature, natural killer cell activity, plasma concentrations of interleukin-1 and cortisol, and the numbers of white blood cells, CD3+ cells, CD4+ cells, CD8+ cells, and CD56+ cells in the peripheral blood. In addition, the study examined whether thermal biofeedback, when presented following the cold pressor tests, would mitigate the effects of the cold pressor tests. Four male university students completed pretest psychological inventories and were pretrained during nine laboratory sessions to increase their skin temperature to 95 degrees Fahrenheit. During the experiment, blood samples were collected at 5-minute intervals and before and after the 1-minute cold pressor tests through an 18-mm catheter inserted into each subject's arm. Subjects were randomly assigned to a matched pair and to the order of experimental conditions, including baseline, the initial cold pressor test, return to baseline, the second cold pressor test, and thermal biofeedback. Each matched pair experienced the conditions in a multiple baseline fashion across subjects during the individual 1.5-hour experimental sessions. Following the experiment, subjects completed posttest psychological inventories, exit interviews, and consumer satisfaction surveys. All subjects demonstrated a decrease in skin temperature ranging from 1 to 1.4 degrees Fahrenheit during the 1-minute cold pressor tests in a multiple baseline fashion, and repeated the temperature decreases within-subjects during the second cold pressor test. Increases in natural killer cell activity ranged from 1% to 14% during the cold pressor tests. For all subjects, both cold pressor tests were associated with increased plasma concentrations of interleukin-1, ranging from 2 to 69 pg/ml. The initial cold pressor tests were associated with increases in all cell numbers in a multiple baseline fashion, but cell numbers varied during the second cold pressor tests. For all subjects, average skin temperatures during the thermal biofeedback conditions were from .3 to .9 degrees higher than during the return to baseline conditions. For all subjects, thermal biofeedback conditions were associated with from 2 to 8 (10^4 cells/ml) higher mean numbers of CD56+ cells than the return to baseline conditions. For 3 subjects, the thermal biofeedback conditions were associated with higher numbers of white blood cells, CD3+ cells, CD4+ cells, and CD8+ cells than the return to baseline conditions. Thermal biofeedback was associated with reductions of from .2 to 26 in the standard deviations of interleukin-1 values, and with a reduced range of cortisol values following the cold pressor tests. Few changes occurred in scores from pre- to posttest on the psychological tests. Subjects rated the goal of learning to relax as very important. All of the subjects stated that they would seek relaxation training for the treatment of a medical or psychological disorder if prescribed. Implications are discussed for design of research in psychoneuroimmunology, for measurement of immune system variables, and for potential clinical applications of these data.
16

Skin temperature variations in the cold

Fournet, Damien January 2013 (has links)
Skin temperature plays an important role in human thermoregulation together with core temperature. Skin temperature varies to a large extent across the body and this is especially pronounced in cold environments. The variations of skin temperature are also involved in the generation of regional thermal perceptions that can lead to behavioural adjustments. Whilst the temporal and inter-individual variations of skin temperature have been well studied using contact sensors, the knowledge of spatial variations has received less attention in the literature. Infrared thermography is a specific imaging technique particularly valuable for the exploration of the topography or pattern of skin temperature across the body. Most research using this technique has only been case studies or experiments focused in one specific body region. However, extensive regional skin temperature data over the whole-body can be proven useful for different types of applications including the sport clothing industry in combination with other body-mapping data. The primary aim of this thesis was to develop an original and standardised method using infrared thermography enabling whole-body skin temperature data to be compared for the assessment of spatial, temporal and inter-individual variations. A specific methodology for infrared data collection and data processing was successfully developed in order to combine data from a variety of participants varying in anthropometrical characteristics. The main outcomes were the production of several skin temperature body maps, either absolute maps to show the magnitude of the temporal or inter-individual effects, and normalised maps (relative to mean skin temperature) allowing for topographical comparisons between protocol stages, populations or interventions. The second aim of the thesis was to extend the understanding of the skin temperature patterns and how these could relate with thermal perceptions. The body-mapping method gave the opportunity to investigate a large amount of conditions, where various internal or external determinants of skin temperature were be involved. This was mainly done in cool to cold environments (5°C to 20°C) where skin temperature is not uniform but is associated with local and overall comfort. Studies were firstly performed in semi-nude conditions (Chapter 3, 4, 5) and then in clothed conditions (Chapter 6 and 7). The semi-nude studies were designed to explore the potential sexdifferences in regional skin temperature responses whilst running (Chapter 3) with a special interest in the role of skinfold thickness, this was further extended with a group of males at rest having a large variety of fat content and thickness (Chapter 4). The influence of exercise type and air temperature on skin temperature patterns was studied with a rowing exercise (Chapter 5). Studies were then performed in clothed conditions (Chapter 5, 6). The influence of real-life conditions on skin temperature patterns and associated perceptual responses was observed during a hiking scenario (Chapter 6). Following these descriptive studies, manipulation of skin temperature patterns was performed using clothing in order to determine the presence of any relevant effect on thermal comfort (Chapter 7). Our results demonstrated that the skin temperature pattern over the whole-body is relatively universal with several features being consistently found regardless of the conditions or the populations. The upper body is usually warmer than the lower body and the body creases (orbital, elbow regions etc.) are also warmer than surrounding regions. A Y-shape of colder temperatures has been highlighted over the anterior torso as well as a T- or Y-shape of warmer temperature over the posterior torso. There are yet some specificities that can be displayed due to active muscles during exercise such as the warmer skin overlying the trapezius and biceps muscles in rowing (Chapter 5), the influence of the backpack construction with up to 3°C warmer skin temperature in the lower back (Chapter 6) or the importance of additional clothing insulation minimizing the anterior Y-shape of colder skin temperatures (Chapter 7). Beyond the thermal patterns, absolute skin temperature differences have been observed between sexes with females displaying 2°C colder skin during semi-nude running (Chapter 3) and 1°C colder skin during clothed walking (Chapter 6)compared to males. The skin temperature difference can also be as large as 6°C colder skin for an obese male compared to a very lean male (40% vs 7% body fat). Despite these differences, there were almost no significant differences in overall and regional thermal sensations and comfort between sexes or between males with varying body fat. Our results focused on body fat revealed that overall fat content and sum of skinfolds was inversely associated with the mean skin temperature response during various protocols (Chapter 4, 6, 7). Local skinfold thickness explained the inter-individual variability of local skin temperature for resting (Chapter 4) and exercising males (Chapter 7) in most body regions. In terms of intra-individual variations, the distribution of skinfold thickness across the anterior torso explained the distribution of skin temperature in this segment solely in conditions with strong regional contrasts (Chapter 3, 4 and 7). When the whole-body skin temperature pattern is considered, our body-mapping approach failed to show relationships between skin temperature distribution across the body and regional skinfold thickness distribution neither at rest nor during exercise. The relative contribution of other internal determinants such as local heat production,local blood flow distribution and local anthropometry should be further investigated to fully elucidate the spatial skin temperature variations depending on the climate, clothing and the body thermal state. Lastly, there was a trend towards improved thermal comfort during rest and exercise in the cold through a manipulation of skin temperature patterns targeting the naturally cold body regions with high insulation, therefore obtaining a more homogeneous skin temperature distribution across the body (Chapter 7). The present work will benefit the sport goods industry. The descriptive results of skin temperature variations will be useful in order to validate multi-segmental model of human thermoregulation. Further work can include pattern predictions for exercise types and conditions not covered by the present thesis. The skin temperature maps will mainly feed the general body-mapping approach for clothing design taking into account several other body mapping data such as sweat mapping and the combination of cold, warm and wetness sensitivity mappings. Lastly, the present results have highlighted the interest for targeted solutions and also the need for more evolutive systems in the field of cold weather apparel.
17

Body temperature manipulation and exercise performance in athletically trained males

Faulkner, Steve H. January 2012 (has links)
Exercise or activity in high ambient temperatures offers a particular challenge to the thermoregulatory system. It is likely that mechanisms such as sweat evaporation alone are not sufficient for maintaining body temperature within a safe limit (~36.5-38.5˚C) and below 40˚C, which may result in impaired physiological function and performance. Exogenous cooling may be of benefit prior to, during and after events that place increased thermal strain due to increased metabolic heat production and elevated environmental temperatures upon the thermoregulatory system. Conversely, in situations where it is not possible to maintain body temperature via either continued physical activity or elevated ambient temperatures, exogenous heating may be required in order to allow optimal physiological performance. Few studies have directly aligned cooling devices with data detailing effective target regions for cooling to allow a pre-cooling garment to be of minimal weight but maximal cooling efficiency. Conversely, no study has considered the effect of muscle temperature maintenance during rest periods on subsequent power-based activities. The aim of this thesis was to determine ways in which body temperature manipulation is capable of improving exercise performance in both power and endurance-based events. It was hypothesised that the manipulation of body temperature will result in subsequent changes in body temperature that would improve performance. Specifically, the use of pre-cooling would result in a reduction of body temperature and improve endurance exercise performance. Conversely, maintaining Tm following warm up completion would have a beneficial effect on sprint and power related performance. Study one set out to determine differences in regional body heat loss in 12 individual anatomical zones using a water perfused suit. Data obtained from this initial study allowed for the specific targeting of regions that were identified as having high rates of heat loss in subsequent studies that focused on pre-cooling and performance. The anatomical regions identified as having high potential affinity for heat exchange with the surrounding environment and cooling devices were the hands, forearms, upper and lower back and torso. Subsequent studies demonstrated that cooling of these areas was capable of lowering thermal sensation and improving thermal comfort prior to and during exercise in moderate environmental conditions (24˚C, 50% RH). In these moderate conditions, there was no statistically significant improvement in treadmill based self-paced 5000m running performance. However, in hot conditions (35˚C 50% RH), the use of a cooling vest and sleeves did yield a significant improvement in cycling time trial performance, which equated to 4.8%. This leads to the suggestion that there may be a threshold ambient temperature, above which pre-cooling becomes an important tool in maximizing performance potential. A parallel area of investigation, on the other side of the temperature spectrum, was the effect of muscle temperature manipulation on power-based exercise performance. The relationship between increased muscle temperature and power output is well established, however little is known about the effect of enforced rest or recovery between two bouts of exercise. Therefore, two studies were conducted to establish what affect a delay between warm up completion and exercise has on muscle temperature and subsequent sprint cycling performance. It was shown that with 30-minutes of rest between exercise bouts wearing tracksuit trousers, muscle temperature declined significantly (~1-1.5˚C). This decline was attenuated with the use of external passive electrical heating during the recovery compared to recovery completed in tracksuit trousers alone. The attenuated decline in muscle temperature following the use of the heated trousers resulted in an improvement in sprint cycling performance (~9%), with the use of insulated trousers having no effect on any variables measured, all relative to wearing tracksuit trousers in the rest period. In a follow-up study, the effect of implementing the heated trousers during the warm up and in addition to the rest period had on muscle temperature increase and sprint performance. A secondary area of investigation in this study was to determine the linearity of muscle temperature decline following warm up cessation. This study demonstrated that there was no additional benefit of combining passive heating with an active warm up on either muscle temperature elevations or subsequent sprint performance compared to the active warm up alone. It was shown that when the no heating was used at any stage, muscle temperature declined exponentially. However, when the heated trousers were used during recovery and/or during warm up, muscle temperature levelled off at a higher value towards the end of the recovery period. This study was also able to show significant improvements in absolute, relative and mean power output following the use of the heated trousers in the warm up and recovery, or the recovery alone. This thesis has identified ways in which body temperature may be manipulated in order to benefit both sprint and endurance exercise performance, using both pre-cooling and active heating. A novel concept for minimizing muscle temperature decline during periods of inactivity between different rounds of competition was shown to maximize sprint performance yielding significant improvements in peak and mean power outputs.
18

Biofeedback and Control of Skin Cell Proliferation in Psoriasis

Benoit, Larry J. 12 1900 (has links)
The present study was designed to determine the effect of skin-temperature-biofeedback training on cellular proliferation in three psoriasis patients. It was hypothesized that (a) psoriasis patients would be able to consciously decrease skin temperature of psoriatic tissue, and (b) there would be a positive correlation between rate of cellular proliferation and temperature change. Results obtained indicated biofeedback training to be effective in decreasing the surface temperature of psoriatic tissue. A 2 X 7 analysis of variance for two repeated measures indicated the change in skin temperatures as a function of sample period to be significant, F (6,26) = 3.29, p < .02. Generalization of temperature-training effects from the biofeedback to the no-feedback condition were observed. Rate of proliferation decreased from pretraining to posttraining biopsies.
19

Parametrizace dyskomfortu organismu řidiče a spolujezdce při monotónní zátěži v průběhu jízdy osobním automobilem / Parameterization of body discomfort of driver and front passanger in a monotone load during driving by car

Kaucová, Jana January 2015 (has links)
Title: Parameterization of body discomfort of driver and front passanger in a monotone load during driving by car Objectives: The aim of this work based on the implemented case study is determination utilization of selected subjective and objective methods to assess discomfort sitting position of driver and front passanger in the monotone load during driving by car. Methods: This thesis is type of descriptive - association qualitative research. In practical part the objective discomfort parameters were monitored using Mobile system for scanning and evaluation of occupational safety and hygiene and the subjective parameters using Questionnaire physical map in combination with modified Borg scale, the mental state was monitored using modified questionnaire POMS. Results: Detailed link was not proved in context of subjective and objective methods or roles, the measurements were too influenced by entering factors and variability of observed objective parameters. The skin temperature, wetness and heart rate appear to be unsuitable for monitoring the sitting discomfort in realistic conditions, subjective methods are usable in research. Their results showed that the subjective discomfort and fatigue grew more during ride back. Pause resulted in reduced subjective discomfort. Keywords: skin temperature,...
20

AnÃlise comparativa das temperaturas das polpas digitais entre gestantes hipertensas e normativas usando termografia de infravermelho / Comparative analysis of temperatures of fingertips between normotensive and hypertensive pregnant women using infrared thermography.

Francisco Eristow Nogueira 30 April 2010 (has links)
Os dados do MinistÃrio da SaÃde apontam a hipertensÃo arterial (HA) como a maior causa de morte materna no Brasil, sendo responsÃvel por 35% da taxa de 140-160 mortes maternas por 100.000 nascidos vivos, sendo sua origem, ainda, motivo de discussÃo. Com a finalidade de buscar novos elementos que permitam o entendimento desta patologia, comparamos as mÃdias das temperaturas das polpas digitais (Tp) de 81 gestantes, 50 normotensas (grupo A) e 31 hipertensas (grupo B), obtidas com termografia de infravermelho. O coeficiente de Pearson mostrou correlaÃÃo positiva entre a pressÃo arterial mÃdia e a pressÃo arterial sistÃlica (r= 0,95), pressÃo arterial diastÃlica (r=0,98) e para a mÃdia das temperaturas cutÃneas das polpas digitais (r=0,98 ). O teste t de student usado para comparaÃÃo de Tp dos grupos A e B foi estatisticamente significante (p = 0,002). A sensibilidade foi de 80%, especificidade de 48%, o VPP de 49%, o VPN de 80%, acurÃcia de 60,5%. A chance de uma paciente estar hipertensa para uma Tp acima de 34,1ÂC à de 1,6 vezes maior. ConcluÃmos a partir dos dados analisados que a mÃdia das Tp de gestantes normotensas à significativamente menor que as mÃdias das Tp de gestantes hipertensas, e que a Tp medida com termografia de infravermelho pode ser um bom preditor para triagem de pacientes normotensas que podem tornar-se hipertensas no decorrer da gravidez. / The Brasilian Healt Ministry data points out arterial hypertension (AH) as the major cause of maternal death, representing 35% of 140-160 maternal deaths for 100.000 alive newborns. Its origin remains a cause for discussion. Looking for new elements that may improve the understanding of that pathology, we studied the skin fingertips mean temperature (Tp) of pregnant women, 50 normotense (group A) and 31 hypertense (group B). The values of temperature were obtained using infrared thermography. Pearson correlation coefficient showed positive relationship between mean arterial pressure and systolic pressure (r= 0,95), diastolic arterial pressure (r=0,98) and for Tp (r=0,98 ). Student t test was statistically significant (p = 0,002) when comparing means of groups A and B. Other statistical tests obtained were: sensibility 80%, specificity de 48%, positive predictive value 49%, negative predictive value 80% and accuracy 60,5%. The chance of a pregnant woman become hypertensive is 1,6 times higher when her Tp is equal or higher then 34,1ÂC. The analyzed data indicate that Tp values of pregnant women measured with infrared thermography is statistically smaller in the group of non hypertense and that may it might become a good method to detect pregnant women with high risk to become hypertensive during pregnancy.

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