Compilation of basal metabolic and blood perfusion rates in various multi-compartment, whole-body thermoregulation models

The assignments of basal metabolic rates (BMR), basal cardiac outputs (BCO) and basal blood perfusion rates (BBPR) were compared in nine multi-compartment, whole body thermoregulation models. The data are presented at three levels of detail: total body, specific body regions and regional body tissue layers. Differences in the assignment of these quantities among the compared models increased with the level of detail, in the above order. The ranges of variability in the total body BMR was 6.5% relative to the lowest value, with a mean of 84.3±2 Watts, and in the BCO it was 8% with a mean of 4.70±0.13 l/min. The least variability among the body regions is seen in the combined torso (shoulders, thorax and abdomen: ±7.8% BMR and ±5.9% BBPR) and in the combined head (head, face, and neck: ±9.9% BMR and ±10.9% BBPR), determined by the ratio of the standard deviation to the mean. Much more variability is apparent in the extremities with the most showing in the BMR of the feet (±117%), followed by the BBPR in the arms (±61.3%). In the tissue layers, most of the bone layers were assigned zero BMR and BBPR, except in the shoulders and in the extremities that were assigned non-zero values in a number of models. The next lowest values were assigned to the fat layers, with occasional zero values. Skin basal values were invariably non-zero but involved very low values in certain models, e.g., BBPR in the feet and the hands. Muscle layers were invariably assigned high values with the highest found in the thorax, abdomen and legs. The brain, lung and viscera layers were assigned the highest of all values of both basal quantities with those of the brain layers showing rather tight ranges of variability in both basal quantities.Average basal values of the "time-seasoned" models presented in this study could be useful as a first step in future modeling efforts, subject to appropriate adjustment of values to conform to most recently available and reliable data

A Study of the Thermal Behavior of Living Biological Tissue With Application to Thermal Control of Protective Suits

212 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1971.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD

Inconsistencies in the "new" wind chill chart at low wind speeds

An apparent error was detected in the calculation of windchill equivalent temperatures (WCETs) in the 'new' chart and corresponding equation that were adopted in 2001 by the weather services in the United States and Canada. The problem is caused by significant discontinuities in WCETs at the assumed 'calm' wind speed condition of 1.34 m s⁻¹. As a result, published WCETs are not equal to, as they should be by definition, but are lower than air temperatures at the assumed calm wind speed condition. This inconsistency further propagates to higher wind speeds beyond the assumed calm condition. In this paper, a straightforward correction is proposed to circumvent these inconsistencies of the new windchill. The proposed correction makes this transition gradual rather than abrupt by applying it to the expression used for estimating the effects of wind on the convective heat exchange coefficient between humans and their cold and windy environment.4 page(s

Compilation of basal metabolic and blood perfusion rates in various multi-compartment, whole-body thermoregulation models

The assignments of basal metabolic rates (BMR), basal cardiac outputs (BCO) and basal blood perfusion rates (BBPR) were compared in nine multi-compartment, whole body thermoregulation models. The data are presented at three levels of detail: total body, specific body regions and regional body tissue layers. Differences in the assignment of these quantities among the compared models increased with the level of detail, in the above order. The ranges of variability in the total body BMR was 6.5% relative to the lowest value, with a mean of 84.3±2 Watts, and in the BCO it was 8% with a mean of 4.70±0.13 l/min. The least variability among the body regions is seen in the combined torso (shoulders, thorax and abdomen: ±7.8% BMR and ±5.9% BBPR) and in the combined head (head, face, and neck: ±9.9% BMR and ±10.9% BBPR), determined by the ratio of the standard deviation to the mean. Much more variability is apparent in the extremities with the most showing in the BMR of the feet (±117%), followed by the BBPR in the arms (±61.3%). In the tissue layers, most of the bone layers were assigned zero BMR and BBPR, except in the shoulders and in the extremities that were assigned non-zero values in a number of models. The next lowest values were assigned to the fat layers, with occasional zero values. Skin basal values were invariably non-zero but involved very low values in certain models, e.g., BBPR in the feet and the hands. Muscle layers were invariably assigned high values with the highest found in the thorax, abdomen and legs. The brain, lung and viscera layers were assigned the highest of all values of both basal quantities with those of the brain layers showing rather tight ranges of variability in both basal quantities.Average basal values of the "time-seasoned" models presented in this study could be useful as a first step in future modeling efforts, subject to appropriate adjustment of values to conform to most recently available and reliable data

Compilation of basal metabolic and blood perfusion rates in various multi-compartment, whole-body thermoregulation models

The assignments of basal metabolic rates (BMR), basal cardiac outputs (BCO) and basal blood perfusion rates (BBPR) were compared in nine multi-compartment, whole body thermoregulation models. The data are presented at three levels of detail: total body, specific body regions and regional body tissue layers. Differences in the assignment of these quantities among the compared models increased with the level of detail, in the above order. The ranges of variability in the total body BMR was 6.5% relative to the lowest value, with a mean of 84.3±2 Watts, and in the BCO it was 8% with a mean of 4.70±0.13 l/min. The least variability among the body regions is seen in the combined torso (shoulders, thorax and abdomen: ±7.8% BMR and ±5.9% BBPR) and in the combined head (head, face, and neck: ±9.9% BMR and ±10.9% BBPR), determined by the ratio of the standard deviation to the mean. Much more variability is apparent in the extremities with the most showing in the BMR of the feet (±117%), followed by the BBPR in the arms (±61.3%). In the tissue layers, most of the bone layers were assigned zero BMR and BBPR, except in the shoulders and in the extremities that were assigned non-zero values in a number of models. The next lowest values were assigned to the fat layers, with occasional zero values. Skin basal values were invariably non-zero but involved very low values in certain models, e.g., BBPR in the feet and the hands. Muscle layers were invariably assigned high values with the highest found in the thorax, abdomen and legs. The brain, lung and viscera layers were assigned the highest of all values of both basal quantities with those of the brain layers showing rather tight ranges of variability in both basal quantities.Average basal values of the "time-seasoned" models presented in this study could be useful as a first step in future modeling efforts, subject to appropriate adjustment of values to conform to most recently available and reliable data