1. 1. In the consideration of ergonomic tasks the attempt is often made to combine the results of physiological research on human perspiration with technical factors such as the transfer of moisture through specific materials.
2. 2. The result of such attempts is often unsatisfactory due to the fact that the percentiles and frequency distribution of perspiration rates are often unknown or not taken into consideration.
3. 3. Further, the interaction between the human user and a particular environmental situation remains unaccounted for.
4. 4. This interaction can produce totally different reactions in both the user and the materials depending upon the specifics of the situation.
5. 5. In response to this deficit we tested 738 persons from various areas in Europe under laboratory conditions to determine perspiration rates and their statistical distribution.
6. 6. Despite the climatic differences existing within Europe, a uniform picture characterized by an extremely skewed distribution resulted.
7. 7. However, it was also shown that these values, including their statistical distribution and percentile ranks, can be strongly influenced by specific external conditions.
8. 8. In the design of human working and living environments it is necessary to examine the situation with research subjects whose perspiration rates are known in order to gain insight into the interactions existing between the human user and the material or technical aspects of the particular environment in question.
Author Keywords: Transpiration; European populations; body support; contact zones 相似文献
Abstract The body temperatures of six apterous species of Namib Desert tenebrionid beetles were measured continuously with indwelling thermocouples under laboratory conditions and in the field. The range of body temperatures selected was within the upper half of their 'tolerated range', which we defined as the temperatures lying between measured critical thermal maximum and critical thermal minimum. In the field, individuals also maintained their body temperatures within the upper half of the 'tolerated range'. These beetles maintained higher body temperatures than those recorded for any other ectothermic insect. Three of the six species maintained lower body temperatures in the field than they selected in the laboratory. The other three species showed no significant difference between field and laboratory body temperatures. We conclude that these beetles are not forced by biotic or abiotic factors to adopt thermal niches which present them with physiological difficulties. 相似文献
Summary Transplantation of fragments of the anterior fat body lobe of 4 day old feeding stage larvae into one day older hosts, which are at the end of feeding, leads to precocious induction of ultrastructural changes in the transplanted cells of the fat body. These changes include alterations in the mean relative and absolute areas of mitochondria, protein granules, lipid droplets and vacuoles. The extent of intracellular changes induced in the transplants depends on the physiological condition of the host. This confirms that alterations in the internal environment at termination of feeding induce premetamorphic changes in cells of the fat body. 相似文献
Abstract. The reproductive tracts of male and female Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae) were described for beetles between emergence and 30 days old in order to determine age-grading criteria. Seminal vesicles were bigger among non-mated males than among mated males due to accumulation of sperm; no age-specific differences were found for male P. truncatus. Ovaries (germarium size, number of follicles and follicle size) were similarly developed for females between 5 and 30 days old and did not differ between mated and non-mated females. Starved females were found to resorb follicles. Yellow body formation was strongly dependent on age, and was used as an age-grading criterion for female P. truncatus. Females flying off maize cobs and caught with pheromone traps were of varying physiological age and mated, and their ovarian development was suspended. All migrating females were mated, indicating that lone females may act as colonizers, independently of males. The applicability of migration theories to P. truncatus and adaptive inter-reproductive dispersal as part of its life history strategy are discussed. 相似文献
Estimates of relationships between blood pressures and anthropometric structure or body composition were made on a total sample
of 414 children, taking age and sex into account. A subsample of 250 children was formed from obese (or slightly obese) subjects.
A different pattern in anthropometric structure and body composition resulted in relation to a different degree of obesity.
A canonical correlation analysis was carried out for each sex, in which a multivariate measure of the linear association between
heart-circulatory functionality parameters, on the one hand, and all the anthropometric traits and body composition parameters,
on the other, was computed. This association resulted statistically significant in both sexes, also if a difference was observed
as concerns the traits that most heavily contributed to the relation-ships between sets of variables, with an evident sexual
dimorphism also in infancy. The necessity of preventive measures and sanitary screening also during infancy was pointed out. 相似文献
Interannual variation in Fulton's condition factor ( K ), total body-fat content and growth rate were investigated for the Icelandic summer-spawning herring Clupea harengus over the period from 1963 to 1999. The results show a close relationship between K and the body-fat content in the autumn, both of which correlated to the growth rate in the same calendar year. A relationship was also found between K during the prespawning season (February to June) and K in the autumn (September to December) in the same year. The different measures of body condition were not found to be related to sea temperature or zooplankton indices, while the spawning stock biomass had negative effects on the fish condition. The results imply that the body condition in the autumn is representative of the feeding success over the whole foregoing year and is therefore related to the growth rate that year. The growth rate appears to be relatively uniform throughout the year. 相似文献
A standard method comprising multi-mesh monofilament nylon gillnets and depth stratification, the Drottningholm method, was employed in test fishing of a small Zambian reservoir (32 ha) on eight occasions over 1 year. The catch per unit effort (cpue) from the 0–3 and 3–6 m zone was timated with benthic and pelagic nets, while in the 6–12 m zone only benthic nets were used. Results include species caught and cpue with coefficients of variation and confidence intervals, for net types and depth zones. A total of 11 species were caught, of which Burbus paludinosus , B. marequensis , Laheo cylindricus , and Oreochromis sp. dominated. Coefficients of variation did not indicate a preferable season for test fishing. During the cold season some species were not caught. The applicability of the method in estimation of species composition and cpue is discussed. 相似文献
Melanocortin 4 receptor (MC4R), which is associated with inherited human
obesity, is involoved in food intake and body weight of mammals. To study the
relationships between MC4R gene polymorphism and body weight in Beagle
dogs, we detected and compared the nucleotide sequence of the whole coding region and 3′-
and 5′- flanking regions of the dog MC4R gene (1214 bp). In 120 Beagle
dogs, two SNPs (A420C, C895T) were identified and their relation with body weight was
analyzed with RFLP-PCR method. The results showed that the SNP at A420C was significantly
associated with canine body weight trait when it changed amino acid 101 of the
MC4R protein from asparagine to threonine,while canine body weight
variations were significant in female dogs when MC4R nonsense mutation at
C895T. It suggested that the two SNPs might affect the MC4R gene’s
function which was relative to body weight in Beagle dogs. Therefore,
MC4R was a candidate gene for selecting different size dogs with the
MC4R SNPs (A420C, C895T) being potentially valuable as a genetic
marker. 相似文献
Summary The ultrastructure of the epithelial cells of Reissner's membrane (membrana vestibularis) in the guinea-pig is described following vascular perfusion with glutaraldehyde of live, anaesthetised and artificially respirated animals. Postfixation in a solution containing OsO4 and potassium ferricyanide revealed a well-developed tubulocisternal endoplasmic reticulum, not previously described, the continuity of which has been mapped by serial sectioning and reconstruction. Large disc-shaped subsurface cisternae lining the cell membrane, but separated from it by a space approximately 10 nm wide, are in continuity with the smooth endoplasmic reticulum, forming an elaborated transcellular canalicular pathway. This structure is compared to that found in solute-transporting epithelia, e.g., renal proximal tubule, gall bladder, small intestine and choroid plexus. The fixation method used in the present study is compared to other techniques used for preservation of Reissner's membrane. Each epithelial cell of Reissner's membrane is endowed with one kinocilium, one to four multivesicular bodies, and a number of intercalated bodies. The functional significance of the canalicular pathway is discussed. 相似文献