Growth status, age, and grade as predictors of school continuation for Guatemalan Indian children

Schooling is considered by many researchers and agencies as an important contributor to individual and national development for populations living in the less developed countries. Accordingly, programs to increase school enrollment and continuation from grade to grade are being developed for many of these countries. This paper investigates the relationship of physical growth status (height, weight, and body composition), grade in school, and age to school continuation for a sample of Indian children living in a village near Guatemala City. It was found that physical growth status, a reflection of health and nutritional status, does not predict school continuation. A child's age and current grade in school do predict continuation. Most children leave school after reaching 9 years of age or after completing the second grade. It is suggested that children may learn enough to satisfy their parents' expectations by this age or grade. Also, the child's economic value to his or her family may be a significant reason for school drop-out.     

双生子骨龄、身高及体重的研究

本文对307对同性别双生子的骨龄、身高和体重进行了研究。结果表明,骨龄、身高和体重均受遗传因素影响。遗传因素对不同年龄阶段的影响程度可能是不同的。长时间的不同环境因素对身高和体重的影响较骨龄更大。     

Do American born Japanese children still grow faster than native Japanese?

Growth patterns of Japanese schoolchildren in Hawaii, composed of 2,954 boys and 3,213 girls aged between 11 and 17, were compared with those comparable groups of Japanese schoolchildren in Japan based on the data published by the Japanese Ministry of Education. Growth characteristics studied were height, weight, and relative weight index, weight/(height). The Hawaii-Japanese boys were taller at early ages but the difference disappeared by age 16. Native Japanese girls were shorter than Hawaii-Japanese until age 13, but they overtook the latter by age 14, exceeding them in height after age 15. A similar pattern was found in weights of girls but the Hawaii-Japanese boys remained consistently heavier by 5.0 to 9.0 kg than native Japanese. The relative weight measure indicated that the Hawaii boys were more "obese" than native Japanese boys for the growth period studied; whereas the same tendency was maintained until age 15 in girls. These observations indicate a marked degree of convergence of the patterns of physical growth of the two populations, whose differences were unmistakably in favor of American born children in earlier studies. It is concluded that the convergence is due largely to the improved environmental conditions in Japan in recent years.     

X-ray small-angle studies of the pyruvate dehydrogenase core complex from Escherichia coli K-12

The pyruvate dehydrogenase core complex from E. coli K-12, defined as the multienzyme complex which can be obtained with a unique polypeptide chain composition, has been investigated in solution with the X-ray small-angle technique. The molecular mass of the core complex of 3.78·10⁶ daltons verifies the ratio of polypeptide chains of 161616 of the three enzyme components, pyruvate dehydrogenase, dihydrolipoamide transacetylase, and dihydrolipoamide dehydrogenase, present in the complex. In connection with the values obtained for the radius of gyration (156.5 å), volume (1.07·10⁷ å³) and amount of solvent associated with the complex (1.03 g/g) a loose packing of subunits in the complex has to be assumed. The maximum diameter of the core complex of 433 å, as determined from the correlation function, corroborates the large extension of the complex. The comparison of experimental and theoretical scattering curves reveals a relatively isometric overall shape of the core complex.Enzymes: Pyruvate dehydrogenase complex = pyruvate dehydrogenase (EC 1.2.4.1) plus dihydrolipoamide transacetylase (EC 2.3.1.12) plus dihydrolipoamide dehydrogenase (EC 1.6.4.3).     

The competition amongDrosophila larvae in different growth stages

1. The experiment was conducted in order to examine the influence of the difference in the growth stage of the competitors on the intraspecific competition. Drosophila melanogaster, “wild” and its mutant “ebony” were used as materials.
2. The earlier developed or older larvae have considerable advantage, such as the increase of the body weight of flies, and of the total weight of flies from one vial, and high constant emerging percentage, while the younger competitors received the opposite influence in addition to the increase of the larval-pupal duration.
3. The grand total yields (the yield of “wild” plus that of “ebony”) from one vial were almost constant even the difference in the growth stage between competitors is changed.

     

Analysis of vegetation structural diversity by Burnaby's similarity index

The application of Burnaby's similarity index is discussed by using structural data from mediterranean vegetation. The index, suggested to compare objects described by characters measured on different scales (mixed data), was applied in a fuzzy theory context. Ordinations of vegetation relevés and structural characters by joint plots have been obtained. These are very useful to map vegetation structural diversity in multidimensional spaces and to test the efficiency of an intuitive classification based on qualitative assessment.     

黄颡鱼重组生长激素的制备及对其鱼苗生长的影响

生长激素在渔业生产中具有重要的应用价值, 通过制备黄颡鱼(Pelteobagrus fulvidraco)同源重组生长激素并用于促生长实验, 从而为建立鱼苗快速培育方法提供理论依据。根据已知黄颡鱼生长激素(PfGH)基因cDNA序列, 利用IPTG诱导和SDS-PAGE分析方法, Western印迹表明在IPTG终浓度1.0 mmol/L、温度17℃和培养时间14h的条件下, 黄颡鱼生长激素基因在大肠杆菌中大量表达, 获得重组生长激素蛋白。然后, 随机选取黄颡鱼分为4组放入室内水族箱中进行养殖, 每箱35尾, 体质量为(0.850.01) g, 每组设3个平行, 水体循环净化。用制备的重组生长激素浓度分别为0、1、5和10 mg/L对黄颡鱼进行浸泡处理, 每周一次, 0为对照组。在养殖4周后, 对各组增重率和特定生长率进行比较, 结果表明1 mg/L组增重率和特定生长率分别比对照组提高了29.67% (P0.05)和11.90% (P0.05), 5 mg/L组增重率和特定生长率分别比对照组提高了21.32% (P0.05)和8.83% (P0.05), 各组间体成分等均无明显差异。停用生长激素4周后, 各组黄颡鱼的生长性能、体成分等均无显著差异。研究表明通过原核表达可以获得黄颡鱼重组生长激素, 用于促进鱼苗生长培育的最佳浸泡浓度为1 mg/L。       

Comparison of self-reported and measured height and weight: Implications for obesity research among young adults

BACKGROUND: The use of self-reported data in epidemiological surveys leads to misclassification of the prevalence of obesity as the participants overestimate or underestimate height, weight and/or both. Such misclassifications vary according to gender, age, status and ethnicity. OBJECTIVES: To estimate on a sample of youth of both sexes (1) the difference between self-reported data and measured height and weight and (2) the extent of misclassification of BMI deriving from such differences. METHODS: Self-reporting in questionnaires and subsequent measurements of height and weight conducted by trained personnel. The mean values and the BMIs were calculated. RESULTS: Both sexes overestimate height (2.1 and 2.8cm for males and females, respectively), and underestimate weight (1.5 and 1.9kg for males and females, respectively). Consequently the BMI is underestimated (1.1 and 1.5 points for males and females, respectively). The classification of BMI from self-reported data shows underestimation of overweight in both sexes (8 percentage points) and of obese males (3.3 percentage points), an overestimation of normal weight (12.2 and 4.3 percentage points for males and females, respectively) and an excessive underweight in the girls (4.3 percentage points). CONCLUSIONS: There is a difference between self-reported and measured data and self-reported biases are reflected in the classification of the participants in the 4 categories of BMI.     

Height, weight and BMI of schoolchildren in Jena, Germany—are the secular changes levelling off?

The secular trend of body height, weight and body mass index (BMI) in 7- to 14-year-old Jena schoolchildren measured in 1975, 1985, 1995 and 2001 is examined. Between 1975 and 1995, a positive trend both in height and weight is observed. In the decade 1985-1995, which includes the time of German reunification, weight shows considerably greater increases than height, resulting in an increasing prevalence of overweight and obesity. The changes in living conditions after reunification cause no remarkable intensification of the secular trend in height. After 1995, the increase in height of boys decelerates, while among girls even a decrease occurs. Girls' weight remains approximately constant between 1995 and 2001 whereas weight among boys continues to increase. The levelling off of the secular increases in height at the end of the twentieth century may be attributed to a possible stabilisation of living conditions.