中国乡村汉族脂肪质量指数与瘦体质量指数的地理性分布

2009-2013年测量了中国36个汉族乡村族群的体质数据值,计算了脂肪质量指数和瘦体质量指数,进行了乡村汉族人的脂肪质量指数、瘦体质量指数与纬度的相关分析。研究结果表明:男性瘦体质量指数与纬度呈正相关(P0.05)。女性的脂肪质量指数、瘦体质量指数与纬度均呈正相关(P<0.01)。从南方到北方,男性瘦体质量指数呈线性增长是导致男性体质量指数与纬度相关的原因。女性瘦体质量指数、脂肪质量指数均呈线性增长,共同导致女性体质量指数与纬度的相关。     

中国人身体质量指数的地理性分布

2009-2013年测量了中国11个汉语方言族群26954例汉族人的身高、体重值,计算了身体质量指数(I_(bm)),将汉族人的I_(bm)与经度、纬度进行相关分析。研究结果表明:总的说来,随年龄增长,11个方言族群I_(bm)值均呈线性增大,并且年龄组间差异均具有统计学意义。11个族群中,北方话族群I_(bm)值明显大于南方各族群。乡村男性(r=0.671; p0.05)、城市女性(r=0.043; p=0.820>0.05)I_(bm)与经度无相关。按照I_(bm)均数大于24.0、I_(bm)均数在23.1～24.0之间、I_(bm)均数小于23.0,可以将中国方言族群分成3个层次,中国北方话族群均分布在第1、2层次,南方族群主要分布在第2、3层次,也就是说11个族群大致按照纬度高低顺序依次分布在第1、2、3层次。遗传、环境、饮食、劳作强度等因素都不同程度影响身高、体重,也影响中国人的I_(bm)值。     

中国汉族青年身高水平的地域分布

本文就１９８５年调查的中国２８个省区乡村汉族青年身高资料,并参考有关报道,采取排序等方法,试绘了一张身高水平分布示意地图。指出：（１）北方较高,南方较矮,这是粗略的提法,更具体地表现为沿海省份比毗邻的内陆省区优越;因而东北是“南高北矮”,广东比湖南高。（２）目前,在高身高区与矮身高区之间,有一条较明确的界线（如附图）。（３）在全国范围内,环渤海地区青年身高最高;而贵州省为最矮。     

中国汉族女性长骨碎片的身高推断

本文作者通过对69副有生前确切资料的中国汉族女性四肢长骨的研究,在女性四肢长骨推断身高的基础上,参考国内外学者的研究方法,选择左右侧肱骨,尺骨,桡骨,股骨,胫骨,腓骨的局部测量项目,其中肱骨8项,尺骨3项,桡骨3项,股骨14项,胫骨8项,腓骨3项,用SPSS软件包对测量项目进行统计分析,建立了中国汉族女性破碎长骨推断身高的回归方程。本文所建方程可以用于中国汉族女性破碎长骨的身高推断,其中肱骨,股骨,胫骨碎片推断身高的效果较好。     

华南地区汉族成年男性肢带骨与身高关系的探讨

为了评价肢带骨推算身高的实用意义,我们测量了近年收集华南地区汉族成年男性、已知生前身高的50具骨骼的肢带骨。测量方法依吴汝康和吴新智的《人体骨骼测量方法》所定的标准。用测骨盘测量锁骨最大长、髋骨最大长,直脚规测量肩胛骨形态宽。应用相关与回归的计算方法,计算各肢带骨左、右侧及其左、右两侧平均值与身高的相关系数、回归系数,并建立了推算身高的回归方法。     

由胸骨长度估算中国北方成年人身高的回归方程

调查了中国北方28具(男15、女13)汉族成年人尸体身高、胸骨全长、胸骨柄长和胸骨体长的均值,并计算了胸骨的长度与身高的相关系数。除男性胸骨全长高度相关外,其余皆为中度相关。由胸骨全长推算身高的回归方程式,较由胸骨柄长和胸骨体长推算身高的回归方程式,有较高的相关系数和较低的标准估计误差。由胸骨体长推算也较由胸骨柄长推算为佳。     

中国汉族儿童少年身高发育城乡差别的变化趋势

本文分析了1985—1995年中国26个省市7—18岁城乡儿童少年身高的发育趋势。总体上看 ,城乡差别明显缩小 ,男女生 7—18岁平均缩小0.55cm和0.64cm,其中以青春发育突增期缩小幅度最大。各省市的变化趋势不一致 ,南方省市缩小较北方明显。     

中国汉族男性腰椎的身高推断

本文研究了中国汉族男性腰椎的测量及腰椎推断身高的方法。测量指标有 :椎体前高、椎体后高、椎体上矢径、椎体下矢径、椎体上横径、椎体下横径、椎体中部横径、椎孔矢状径、椎孔横径、左侧椎弓根厚度。将各腰椎的测量数据与身高进行了相关分析并建立了中国汉族男性腰椎推断身高的回归方程。本研究所建立的方程 ,可以用于中国汉族男性腰椎的身高推断。     

现代中国人身高的变异

本文依据16个省汉族和23个少数民族身高平均值,运用方差分析法分析和讨论了当代中国人身高的地理变化,男女两性身高的群体变化趋势。     

城市汉族的瘦体质量和脂肪质量

2009-2013年测量了城市汉族成人10451例(男性5048例,女性5403例)的16项指标值,研究了不同纬度地区汉族城市成人的瘦体质量、脂肪质量值的变化规律。研究发现:1)31个族群脂肪质量、瘦体质量均数彼此相差较大,脂肪质量最大值男性、女性均为保定汉族;最小值男性为宜春汉族、女性为宁乡汉族。瘦体质量最大值男性为呼兰汉族、女性为南阳汉族;最小值男性为赣州汉族,女性为琼海汉族。2)各族群女性脂肪质量值均大于男性,而瘦体质量值均小于男性。3)胸部、臀部(女性还有腹部)围度的发育以及全身的皮下脂肪发育水平影响着城市汉族脂肪质量的发育水平,躯干与下肢围度(男性还有上肢骨骼)发育情况影响着城市汉族人的瘦体质量发育水平。4)随纬度的增加,即从中国的南方到北方,城市汉族人的体质量、脂肪质量、瘦体质量均呈线性增大。脂肪质量、瘦体质量随纬度增加而增大共同引起了体质量规律性的变化。     

Evaluation of juvenile stature and body mass prediction

This investigation evaluates the performance of juvenile stature (from tibia and radius lengths) and body mass (from breadth of the femoral distal metaphysis) prediction equations based on the Denver Growth Study sample (Ruff C. 2007. Am J Phys Anthropol 133 698-716). The sample used here for evaluation is an independent sample of juveniles brought to the Franklin County (Ohio) Coroner in 1990-1991. The Ohio sample differs somewhat from the Denver reference sample: it includes approximately 25% African-Americans (rather than all European-Americans), a significant number of right limb bones were measured (rather than all left side), it includes a wider range of economic statuses and it includes individuals who died from disease and trauma. As such the composition and measures of the Ohio sample correspond more generally to that seen in skeletal samples so that the accuracy of the estimates from the present sample should approach those found in practical applications of these methods. Results indicate that both juvenile body mass and stature are estimated relatively accurately. Accuracy of body mass estimates for 1-13-year-old juveniles is similar for African-American and European-American males and females. The least accurate estimates are for individuals in the 8-13 years age class (excluding individuals with body mass indices greater than the age specific 95th percentile): n = 9, +/- 2.9 kg, 95% confidence interval 1.4-4.4 kg. Accuracy of stature estimates for 1-17-year-old juveniles is comparable for the tibia and radius and, as with body mass estimates, are similar for African-American and European-American males and females. For combined age, sex, and ancestry groups average accuracies are in the +/-3.5 to +/-6.5 cm range. Some limitations of the methods are discussed.     

Age and body mass index associations with body segment parameters

Body segment parameters (BSPs) such as segment mass, center of mass, and radius of gyration are required in many ergonomic tools and biomechanical models to estimate injury risk, and quantify muscle and joint contact forces. Currently, the full effects of age and obesity have not been taken into account when predicting BSPs. The goal of this study is to quantify the impact of body mass index (BMI) and age on BSPs, in order to provide more representative measures necessary for modeling inputs. A whole body dual energy X-ray absorptiometry (DXA) scan was collected for 280 working men and women with a wide range of BMI and aged 21 to 70 years. Established DXA processing methods were used to determine in-vivo estimates of the mass, center of mass, and radius of gyration for the upper arm, forearm, torso, thigh, and shank for males and females. Regression models were used to determine if age and BMI terms, as well as their interactions, were associated with these BSPs. The variability in BSPs explained by BMI alone ranged from 4 to 51%, and age explained an additional 3–19%. Thus, BMI and age are significant correlates of BSPs, and need to be taken into account when predicting certain BSPs in order to obtain accurate and representative results in biomechanical models.     

Age variations in the relation of body mass indices to estimates of body fat and muscle mass

In some chronic disease studies, distinctions have been made regarding the importance of body mass index (BMI) as a risk factor in younger versus older men and women. In order to determine the significance of these differences in BMI-disease associations, we determined the extent of age-dependent variations in the relation of BMIs to body composition in large probability samples of U.S. men and women from the First and Second U.S. National Health and Nutrition Examination Surveys (NHANES I and II). BMIs are more highly correlated with estimates of body fat in younger than in older men and women, and with muscle mass in older than in younger adults. Caution should be exercised in interpreting the significance of BMI as a risk factor for chronic disease, particularly in comparison of age groups.     

Geographical patterns of body mass distribution are robust even when inserting uncertainty in average estimates of species body mass

Pardiñas, Valenzuela, and Salazar‐Bravo (2017) are concerned that eventual differences in species mean body masses and in the phylogenetic hypothesis used in Maestri et al. (2016)—compared with those available on other potential sources—could affect the results of our original article. Here, we used a new phylogenetic hypothesis to conduct the same analyses of the original article, and we randomly sampled 1000 values of body mass within approximately 35% upper and lower intervals around the mean body mass for each species included in our database. We show that our previous results and conclusions are robust and valid, and they persist despite uncertainty in mean body mass estimation. We argue that sampling variation and uncertainty in both species mean body mass estimation and phylogenetic hypothesis are to be expected and should not always be confused with inaccuracies.     

The effect of short-term changes in body mass distribution on feed-forward postural control

It was recently shown that short-term changes in the whole body mass and associated changes in the vertical position of the center of mass (COM) modify anticipatory postural adjustments (APAs) [Li X, Aruin AS. The effect of short-term changes in the body mass on anticipatory postural adjustments. Exp Brain Res 2007;181:333–46]. In this study, we investigated whether changes in the body mass distribution and related changes in the anterior–posterior COM position affect APA generation. Fourteen subjects were instructed to catch a 2.2 kg load with their arms extended while standing with no additional weight or while carrying a 9.08 kg weight. Adding weight to a backpack, front pack or belly pocket was associated with an increase of the whole body mass, but it also involved changes in the anterior–posterior (A/P) and vertical positions of the COM. Electromyographic activity of leg and trunk muscles, body kinematics, and ground reaction forces were recorded and quantified within the typical time intervals of APAs. APAs were modified in conditions with changed body mass distribution: increased magnitude of anticipatory EMG activity in leg and trunk muscles, as well as co-activation of leg muscles and decreased anticipatory displacement of the COM in the vertical direction, were seen in conditions with increased body mass. Changes in the COM position induced in both A/P and vertical directions were associated with increased anticipatory EMG activity. In addition, they were linked to a co-activation of muscles at the ankle joints and significant changes in the center of pressure (COP) position. Modifications of the COM position induced in the A/P direction were related to increased anticipatory EMG activity in the leg and trunk muscles. At the same time, no significant differences in anticipatory EMG activity or displacement of COP were observed when changes of COM position were induced in the vertical direction. The study outcome suggests that the CNS uses different strategies while generating APAs in conditions with changes in the COM position induced in the anterior–posterior and vertical directions.     

The role of body mass in thermoregulation

Inbred Fisher and Buffalo rats were raised in small and in large litters and by such litter manipulation, large- and small-bodied animals were obtained within the same strain. When the rats were exposed to extreme cold and heat, it appeared that large-bodied rats in both strains survived longer in cold and small-bodied rats survived longer in heat. The two trends were clearly evident, and individual correlations between survival time and body mass were generally significant. However, there were also irregularities in such correlations. It is concluded that this is due to the fact that body mass is only one factor determining temperature tolerance in addition to hypothalamic, endocrine, and possibly neurochemical factors not known to be correlated to body mass.     

Modeling of body mass index by Newton's second law

Since laws of physics exists in nature, their possible relationship to terrestrial growth is introduced. By considering the human body as a dynamic system of variable mass (and volume), growing under a gravity field, it is shown how natural laws may influence the vertical growth of humans. This approach makes sense because the non-linear percentile curves of different aspects of human physical growth from childhood to adolescence can be described in relation to physics laws independently of gender and nationality. Analytical relations for the dependence of stature, measured mass (weight), growth velocity (and their mix as the body mass index) on age are deduced with a set of common statistical parameters which could relate environmental, genetics and metabolism and different aspects of physical growth on earth. A relationship to the monotone smoothing using functional data analysis to estimate growth curves and its derivatives is established. A preliminary discussion is also presented on horizontal growth in an essentially weightless environment (i.e., aquatic) with a connection to the Laird-Gompertz formula for growth.