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1.
The aim of this study is to investigate whether there are differences in body dimensions between children of the same sex from endogamic and exogamic matings. The cross-sectional sample consisted of 285 children, 136 males and 149 females, 6 to 10 years old, attending elementary schools in Tortolí, a town in east-central Sardinia. The children of each sex were divided into two groups: endogamic and exogamic, the first including children from parents born in the same Sardinian village, the latter children from parents born in two different places. For each sex, ANCOVA with age as covariate revealed no significant differences between the two groups of children for the 35 anthropometric variables considered. Moreover, for each sex, there were no significant differences between the two groups of children for some anthropometric variables considered to be indicators of nutritional status: sums of skinfold thicknesses, waist/hip ratio, body mass index, total upper arm area, upper muscle arm area, upper arm fat area. We conclude that when Sardinian children of endogamous and exogamous unions are in similar nutritional conditions, they do not differ in body dimensions.  相似文献   

2.
Data about the effects of working environment and excessive physical loads on human growth and constitution are insufficient. Although there are a few studies which link growth retardation in children's stature and long bones to their exposure to hard labor, it is difficult to discern whether the detrimental effects of compressive forces on growth result solely from severe compressive stresses or from the subjects' poor economic and substandard nutritional conditions as well. The aim of this study was to clarify this issue by comparing the anthropometric dimensions of laboring and non-laboring adolescents; both groups came from lower socioeconomic strata and were subject to poor living conditions. The laboring group consisted of 532 male apprentices aged 13.5-18.5, and the control group, of their 451 non-laboring peers who were attending school during the period of observation. Body weight, 3 vertical dimensions (stature, upper and lower limb lengths), 2 diameters (elbow and knee breadths), and 3 circumferences (contracted and relaxed upper arm girth and calf girth) were measured. In addition, relative growth according to the body height for each variable was computed, since relative variables are more valuable in evaluating the effects of excessive loading on the human body. The analyses showed that all vertical dimensions of laboring adolescents lagged behind those of their non-laboring peers. There were also clear differences between the two groups with regard to relative diameters and girths. The pressure effects of physical activity stimulate the transversal growth of the long bones. Similarly, circumferences, especially contracted upper arm girth relative to stature, are more developed in the laboring group than in the non-laboring group. These findings suggest that excessive workloads retard adolescents' vertical growth, especially in upper parts of the body, but that they stimulate transversal growth of the long bones and muscle development.  相似文献   

3.
Mean values and standard deviations of total body volume, body density, arm volume, height, weight and a battery of 15 measurements of arm comprising different lengths, girths, diameters and skinfolds of 200 Punjabi girls aged 10–19 years are presented. Relationship between arm volume and total body volume in different age groups are also studied. Highly significant and positive correlations existed between arm volume and total body volume and the values of correlation coefficients r ranged between 0.78 to 0.92 in different age groups. Body volume was estimated also from arm measurements by using selective stepwise multiple linear regression analysis for each age group. Highly significant multiple correlation coefficients R were obtained for predicting total body volume from arm measurements and the values of multiple R ranged between 0.92 to 0.97 in different age groups even with a combination of just three or four arm measurements. The most commonly selected measurements up to fourth step in most of the age groups were upper arm girth and maximum forearm girth.  相似文献   

4.
Data on 34 anthropometric measures from the Alexanderwohl Mennonite congregations of Kansas and Nebraska are presented. A factor analysis of these traits shows that body length and body width measures are distinct from each other as well as from measures of the head and face. Moreover, familial correlations estimated by maximum likelihood for all 34 traits tend to separate from each other along factor lines with correlations for body lengths being the highest and those for skinfolds and circumferences being the lowest. These results suggest the presence of various body "fields" which are under differing degrees of genetic and environmental control. We offer the term "functional multifactorial complex" as a means of referring to the joint genetic and environmental influences on these fields.  相似文献   

5.
The aim of this study was to investigate if there are differences in body dimensions among children from matings of different levels of exogamy. The cross-sectional sample consisted of 285 children, 136 males and 149 females, 6 to 10 years old, attending elementary schools in Tortoli, a town in east-central Sardinia. The children were divided into four groups according to the level of exogamy. One of them included the children of parents born in the same Sardinian village is highly endogamous. For each sex, the Kruskal-Wallis test revealed no significant differences among the four groups of children for the 35 anthropometric variables considered, with the exception of head circumference in the male sample. In particular, there were no significant differences among the four groups of children for some anthropometric variables that are considered to be indirect indicators of nutritional status: sum of skinfolds, waist/hip ratio, body mass index, total upper arm area, upper arm muscle area, upper arm fat area. We conclude that Sardinian children from marriages of different levels of exogamy do not differ in body dimensions if they have similar nutritional conditions.  相似文献   

6.
The method proposed for the study of DNA conformational transitions is based on the proportionality, experimentally observed, between the length of a DNA fiber and the axial rise per nucleotide characterizing the molecular helix. Precise curves for the A-B and B-C transitions as a function of the relative humidity are obtained by using X-ray fiber data and measurements of fiber dimensions. It is thus shown that the A-B transition is a cooperative process between two different states, whereas the B-C transition can be considered as a progressive change of conformation. The present method is applied on two natural DNAs differing in base composition so that the effect of the nucleotide content on the conformational changes can be estimated.  相似文献   

7.
Allometric scaling relationships between body weight, bone length, and cross-sectional dimensions of the lower limb bones which measure structural strength and rigidity (area, second moments of area) are investigated in Homo, Gorilla, Pan, Pongo, and Macaca. Cross-sectional dimensions are slightly positively allometric and highly correlated with body weight; within-bone proportional differences are largely a result of differences in relative bone length to body weight. Orangutans show the greatest deviation from general scaling relationships between lower limb bone structural strength and weight, probably due to habitual upper limb suspension. Formulas for the prediction of weight from cross-sectional dimensions are presented.  相似文献   

8.
The dimensions of the living and working space and buildings, the types of material and different riggings should be designed to conform to the users' anthropometric measures. The first requirement to design on ergonomic system is to measure the human being who will work and live in that system. Because of this, anthropometric measures are the most frequently used ergonomic data during the design process. In this research paper, we attempt to organize a new data base of anthropometric data to use in the design of children's equipment and furniture used in crèches. A starting point for research on the proper dimensions of creche furniture is to investigate how the dimensions of furniture reflect the body dimensions and the functional needs of the children using furniture. The anthropometric data of 3, 4 and 5 year-old-children in crèches was used. We report the results of the measurements of 18 anthropometric characteristics of children which constitute a set of basic data for the design of functional spaces and furniture.  相似文献   

9.
The measurement of short-term changes in maternal body composition during the post-partum period under field conditions poses many problems: (1) body composition techniques depend on the constancy of the proportions of components or their physical properties and are less suitable for measuring changes; (2) many of the techniques require expensive, technically sophisticated apparatus that is inappropriate to field conditions in many countries; (3) changes in body composition affect some areas of the body more than others so regional as well as whole body approaches are required. The measurements of body weight, triceps and subscapular skinfold thicknesses and upper arm circumference are essential measurements. These can be supplemented with further skinfold thicknesses and circumferences, and possibly body density and body water measurements. There is little to be gained by transforming anthropometric variables into whole body composition indices in these circumstances.  相似文献   

10.
Skeletal muscle (SM), the body's main structural support, has been implicated in metabolic, physiological, and disease processes in humans. Despite being the largest tissue in the human body, its assessment remains difficult and indirect. However, being metabolically active it contains over 50% of the total body potassium (TBK) pool. We present our preliminary results from a new system for measuring partial body K (PBK) that presently are limited to the arm yet provide a direct and specific measure of the SM. This uniquely specific quantification of the SM mass in the arm, which is shielded from the body during measurement, allows us to simplify the assumptions used in deriving the total SM, thereby possibly improving the modeling of the human body compartments. Preliminary results show that PBK measurements are consistent with those from the TBK previously obtained from the same subjects, thus offering a simpler alternative to computed tomography and magnetic resonance imaging used for the same purposes. The PBK system, which can be set up in a physician's office or bedside in a hospital, is completely passive, safe, and inexpensive; it can be used on immobilized patients, children, pregnant women, or other at-risk populations.  相似文献   

11.
在不惊扰蜘蛛的情况下对悦目金蛛Argiope amoena和圆尾肖蛸Tetragnatha vermiformis的个体大小与蛛网粘丝区面积问的相关性进行了野外观察。主要测量了蜘蛛体长、蛛网粘丝区直径、蛛网框丝固着点间最大距离、网中枢到地面或水面距离、网平面与水平线的夹角等参数;另外还对蛛网框丝固着点间最大距离作为圆网蛛网址选择行为量化指标的可行性进行了探讨。结果表明,2种蜘蛛体长与蛛网粘丝区面积以及蜘蛛体长与蛛网框丝固着点间最大距离均呈现明显的正相关。悦目金蛛体长与蛛网粘丝区面积的相关性高于圜尾肖蛸,这可能与悦目金蛛在其生境中易于找到框丝固着点、而圆尾肖蛸在其生境中较难找到框丝同着点有关;  相似文献   

12.
Great Bear Lake is the most northerly lake of its size and provides unique opportunities for intraspecific diversification. Despite increasing attention to intraspecific polymorphism, several knowledge gaps remain (e.g. determining the extent of intraspecific diversification in large relatively pristine lakes and at which spatial scale it can occur). We focused on geographical patterns of morphological differentiation within lake trout (Salvelinus namaycush) to describe two levels of intralake diversification in Great Bear Lake. We used a combination of geometric and traditional linear measurements to quantify differences in body shape, head shape, and fin and body lengths among 910 adult lake trout from the five distinct arms of Great Bear Lake. Although head and fin linear measurements discriminated the three common morphotypes at the whole‐lake level, inter‐arm variation in body shape was observed within each morphotype. A comparison of genetic and morphological distance matrices revealed the lack of an association between the two sets of data, although both comparisons revealed an association in the inter‐arm variation patterns among morphotypes, suggesting a phenotypically plastic response to distinct environments. The whole‐lake and inter‐arm morphological variation observed within lake trout demonstrates the importance of considering scale, especially across large lakes that exhibit marked complexity and a variety of freshwater habitats. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 114 , 109–125.  相似文献   

13.
Anthropometric dimensions of Indian housewives have been measured from the viewpoint of architectural and product design ergonomics. Altogether, 79 different body dimensions were measured on 147 urban housewives of age range varying between 21 to 56 years. The average stature and weight of Indian housewives as observed in this study were 153.2 cm (SD +/- 5.7) and 55.1 kg (SD +/- 9.7), respectively. Average values along with 5th and 95th percentile values for all measurements have been determined. Values were compared with other Indian studies. A correlation between the body height, weight, and other measurements were obtained with the help of a PDP 11/23 microcomputer. Based on the existing data ratio scale relationships between the body height and other measurements of Indian women were determined. An anthropometric data, pack is presently lacking; therefore, the findings herein can be used while determining household workplace layouts, evaluating area specifications, determining work-surface heights, clearances, reach, etc. A similar study on a larger population size for Indian women has been suggested for establishing national standards.  相似文献   

14.
Icosahedral viral capsids assemble with high fidelity from a large number of identical buildings blocks. The mechanisms that enable individual capsid proteins to form stable oligomeric units (capsomers) while affording structural adaptability required for further assembly into capsids are mostly unknown.Understanding these mechanisms requires knowledge of the capsomers’ dynamics, especially for viruses where no additional helper proteins are needed during capsid assembly like for the Mavirus virophage that despite its complexity (triangulation number T = 27) can assemble from its major capsid protein (MCP) alone. This protein forms the basic building block of the capsid namely a trimer (MCP3) of double-jelly roll protomers with highly intertwined N-terminal arms of each protomer wrapping around the other two at the base of the capsomer, secured by a clasp that is formed by part of the C-terminus.Probing the dynamics of the capsomer with HDX mass spectrometry we observed differences in conformational flexibility between functional elements of the MCP trimer. While the N-terminal arm and clasp regions show above average deuterium incorporation, the two jelly-roll units in each protomer also differ in their structural plasticity, which might be needed for efficient assembly. Assessing the role of the N-terminal arm in maintaining capsomer stability showed that its detachment is required for capsomer dissociation, constituting a barrier towards capsomer monomerisation. Surprisingly, capsomer dissociation was irreversible since it was followed by a global structural rearrangement of the protomers as indicated by computational studies showing a rearrangement of the N-terminus blocking part of the capsomer forming interface.  相似文献   

15.
Prediction of body weight of fossil Artiodactyla   总被引:1,自引:0,他引:1  
Many dimensions of the postcranial skeleton of ruminant artiodactyls scale closely with body weight and are therefore potentially useful as predictors of body weight in fossil species. Using 45 dimensions of the skeleton a series of predictive equations was generated based on the scaling relationships of the family Bovidae. As a test of their usefulness these equations were used to predict body weights of a number of living ruminant artiodactyls, and six genera of fossil artiodactyls. For most species body weight estimates within 25° of actual weight were given by the mean of the predicted weights from all measurements except lengths of long bones. While femur length was a reasonable predictor of body weight, lengths of distal long bones were unreliable and should not be used as indicators of relative or absolute body weights. Some non-length measurements are biased in certain taxonomic groups; the possibility of erroneous estimates from such measurements can be reduced by using as many estimators of body weight as are available. No species of artiodactyl tested is so highly modified in all dimensions that all results were erroneous. Subsets of measurements which might be available from a typical fossil fragment also gave reliable results.  相似文献   

16.
It is well known that predators can induce morphological changes in some fish: individuals exposed to predation cues increase body depth and the length of spines. We hypothesize that these structures may evolve synergistically, as together, these traits will further enlarge the body dimensions of the fish that gape-limited predators must overcome. We therefore expect that the orientation of the spines will predict which body dimension increases in the presence of predators. Using phylogenetic comparative methods, we tested this prediction on the macroevolutionary scale across 347 teleost families, which display considerable variation in fin spines, body depth and width. Consistent with our predictions, we demonstrate that fin spines on the vertical plane (dorsal and anal fins) are associated with a deeper-bodied optimum. Lineages with spines on the horizontal plane (pectoral fins) are associated with a wider-bodied optimum. Optimal body dimensions across lineages without spines paralleling the body dimension match the allometric expectation. Additionally, lineages with longer spines have deeper and wider body dimensions. This evolutionary relationship between fin spines and body dimensions across teleosts reveals functional synergy between these two traits and a potential macroevolutionary signature of predation on the evolutionary dynamics of body shape.  相似文献   

17.
The nutritional status of Trio and Wajana is representative of a group living under primitive conditions in a favourable environment. In adults, skinfold thickness remains constant throughout life. The folds of females are thicker than those of males, the difference being most marked over the triceps and least at the subscapular. In children, skinfold thickness at the subscapular and suprailiac sites decreases from the 3–4 to the 5–6 age group, after which there is a rapid increase towards adult values. Age changes over the triceps are less marked, especially in males. Other measurements included arm and calf circumference, bone dimensions at the wrist, elbow, ankle and knee, weight, stature, leg and arm length and biacromial breadth. The two tribes differ significantly in several measurements. The Wajana are heavier but they tend to be shorter in stature, with shorter legs but broader elbows and wrists. Shoulder breadth and the circumference of the upper arm are greater in Wajana males but females do not show these differences. The Wajana have longer and broader heads, but the cephalic index is similar. The tribes also differ in hair texture.  相似文献   

18.
The effects of an extra X chromosome on size and shape of body and head were studied in 47,XXY males; 25 anthropometric measurements were recorded from 29 adult 47,XXY males and compared with those of male relatives and control males. In stature, arm length, leg length, triceps skinfold, and subscapular skinfold 47,XXY males were larger and in biacromial diameter, bideltoid breadth, wrist breadth, and in most head dimensions smaller than normal males. Arm length was increased less than leg length. Increase in stature seemed to be caused solely by increased leg length, and the somewhat feminine proportions in trunk were caused by decrease in biacromial diameter. Correlations of the body and head dimensions between 47,XXY males and their male relatives were found to be normal. The present findings support the earlier proposals that X chromosome carries genes which influence linear growth. It is suggested that the reduction in biacromial diameter is caused by lowered plasma testosterone level which may also have affected sitting height. The control of body and head dimensions seems to be maintained relatively normal.  相似文献   

19.
Background and Aims Plant growth, the increase of organ dimensions over time, and development, the change in plant structure, are often studied as two separate processes. However, there is structural and functional evidence that these two processes are strongly related. The aim of this study was to investigate the co-ordination between growth and development using mango trees, which have well-defined developmental stages.Methods Developmental stages, determined in an expert way, and organ sizes, determined from objective measurements, were collected during the vegetative growth and flowering phases of two cultivars of mango, Mangifera indica. For a given cultivar and growth unit type (either vegetative or flowering), a multistage model based on absolute growth rate sequences deduced from the measurements was first built, and then growth stages deduced from the model were compared with developmental stages.Key Results Strong matches were obtained between growth stages and developmental stages, leading to a consistent definition of integrative developmental growth stages. The growth stages highlighted growth asynchronisms between two topologically connected organs, namely the vegetative axis and its leaves.Conclusions Integrative developmental growth stages emphasize that developmental stages are closely related to organ growth rates. The results are discussed in terms of the possible physiological processes underlying these stages, including plant hydraulics, biomechanics and carbohydrate partitioning.  相似文献   

20.
The site-specific recombinase (Int) of bacteriophage lambda is a heterobivalent DNA-binding protein that binds two different classes of DNA-binding sites within its recombination target sites. The several functions of Int are apportioned between a large carboxy-terminal domain that cleaves and ligates DNA at each of its four "core-type" DNA-binding sites and a small amino-terminal domain, whose primary function is binding to each of its five "arm-type" DNA sites, which are distant from the core region. Int bridges between the two classes of binding sites are facilitated by accessory DNA-bending proteins that along with Int comprise higher-order recombinogenic complexes. We show here that although the 64 amino-terminal residues of Int bind efficiently to a single arm site, this protein cannot form doubly bound complexes on adjacent arm sites. However, 1-70 Int does show the same cooperative binding to adjacent arm sites as the full length protein. We also found that 1-70 Int specifies cooperative interactions with the accessory protein Xis when the two are bound to their adjacent cognate sites P2 and X1, respectively. To complement the finding that these two amino-terminal domain functions (along with arm DNA binding) are all specified by residues 1-70, we determined that Thr75 is the first residue of the minimal carboxy-terminal domain, thereby identifying a specific interdomain linker region. We have measured the affinity constants for Int binding to each of the five arm sites and the cooperativity factors for Int binding to the two pairs of adjacent arm sites, and we have identified several DNA structural features that contribute to the observed patterns of Int binding to arm sites. Taken together, the results highlight several interesting features of arm DNA binding that invite speculation about additional levels of complexity in the regulation of lambda site-specific recombination.  相似文献   

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