Influence of ethnicity, geography and climate on the variation of stature among Indian populations

This paper analyzes the variation in the mean stature of adult males of a variety of population groups in India and examines the influence of geographical, climatic and ethnic factors on it. A considerable variation in mean stature has been found with respect to these three attributes. Variation "between" ethnic groups compared with "within" ethnic groups was found to be much more than that of geographical and climatic zones. Scheduled Castes (SC) and Scheduled Tribes (ST) populations have much low average height than that of General Castes (GC). Climatically dry and semiarid zones have a tendency to have higher stature than in the Monsoon areas. The mean height has been found to be the highest in north India. It is closely followed by west India. An interesting feature is that as one goes towards east and south the mean height gradually decreases. It is the lowest in islands. The mean heights have been regressed on geographical, climatic and ethnic factors, after converting these factors into binary variables. The regression analysis has strengthened the findings, that there is a highly significant relationship between height and geographical, climatic and ethnic factors.     

Upper-body anthropometric and strength measures and their relationship to start time in elite luge athletes

Start time has been shown to be a significant predictor of overall performance in the sport of luge. The starting motion in luge has been described as an explosive upper-body movement that requires significant technique and skill to perfect. This study aims to investigate upper-body factors that may relate to start time in luge. Twenty-two subjects participated in the study as part of their normal off-season training. Each subject had a minimum of 3 years' experience in the sport of luge, and at the time was a member of a U.S. Luge National Team. Subjects completed a 1 repetition maximum (1RM) in the bench press (BP), prone row (PR), and weighted pull-up (WP). Anthropometric distances were taken measuring finger-tip span (FS), biacromial breadth (BB), acromio-radial length, acromio-olecranon length (AO), hand length, and sitting cervical height. Subjects were divided into 2 groups based on which U.S. Luge National team they were currently a member of, Senior National (SN, n = 13) and Junior National (JN, n = 9). A Pearson product-moment correlation coefficient showed several significant (p ≤ 0.05) relationships between upper-body variables and start time among the groups. The BP and PR 1RM were shown to have a significant relationship in both groups. Among the anthropometric variables, AO was also significant in both groups. The WP, FS, BB, and height were all shown to have a significant relationship with start time in the SN group, but not in the JN group. These results suggest that as luge athletes become more efficient in the starting technique, outside factors such as upper-body strength and anthropometric measures play a larger role in performance.     

Lack of Association of Diagonal Earlobe Crease With Other Cardiovascular Risk Factors

The relationship between diagonal earlobe crease and coronary risk factors, controlling for age and sex effects, was tested in 686 persons. A positive correlation (ρ=.86, P<.001) is obtained between age and percentage of persons with earlobe creases in each one-year age interval; no sex difference is seen. To test for associations between cardiovascular risk factors and earlobe creases, 67 persons with creases are compared with 67 controls (matched by age and sex) without creases, using the following variables: diastolic and systolic blood pressures, cigarette smoking, weight, height, scapular skinfold thickness, serum cholesterol level, high-density lipoprotein level, intracellular sodium, sodium-lithium countertransport, plasma renin level and the presence of diabetes and hypertension. None of these variables differs significantly between cases and controls, indicating that the previously documented association between earlobe crease and coronary heart disease may be independent of these risk factors. Although coronary heart disease has often been shown to aggregate in families, no familial aggregation is found for earlobe creases.     

Biogenic aldehyde metabolism in rat brain. Differential sensitivity of aldehyde reductase isoenzymes to sodium valproate

The effects of inhibitors of aldehyde reductase (alcohol:NADP+ oxidoreductase, EC 1.1.1.2) on the formation of 3-methoxy-4-hydroxyphenethylene glycol from normetanephrine have been studied in rat brain homogenates. The reaction pathway was shown to be unaffected by several inhibitors of the major (high Km) form of aldehyde reductase such as sodium valproate. Two isoenzymes of aldehyde reductase have been separated and characterized from rat brain. The minor (low Km) isoenzyme is shown to be relatively insensitive to sodium valproate and exhibits a similar inhibitor-sensitivity profile to that obtained for methoxyhydroxyphenethylene glycol formation. The low Km isoenzyme is therefore implicated in catecholamine metabolism. The metabolism of succinic semialdehyde and xylose by rat brain cytosol has also been examined. Aldose metabolism may also be attributed to the action of the low Km reductase, but the existence of a separate succinic semialdehyde reductase is postulated. The possible roles of aldehyde reductases in brain metabolism and the relationship between these enzymes and aldose reductase (alditol:NADP+ 1-oxidoreductase, EC 1.1.1.21) are discussed.     

Reproductive and socioeconomic determinants of child survival: Confounded,interactive, and age‐dependent effects

Abstract

Studies of infant and child mortality have evolved to distinguish between two sets of explanatory variables—factors related to reproductive or maternal characteristics and socioeconomic factors, generally described as characteristics of the family or household. Almost all multivariate analyses include variables from each of these two sets, but there has been little consideration of the relationship between them. We examine how these two sets of variables jointly affect mortality. We test first for confounded effects by examining socioeconomic effects while excluding and then including reproductive variables in nested multivariate models. Next, we look for age‐dependent effects among the explanatory variables and find that reproductive and socioeconomic factors affect mortality at differing ages of children. Finally, we examine interactive effects of the two sets of variables. We conclude that the higher mortality observed among the low status groups is not a result of greater concentration of poor reproductive patterns in those groups. Instead, higher status groups probably have more resources available for combating the negative effects of the same high‐risk reproductive patterns.     

Prediction of serum testosterone before and after an exercise program using physiological and personality variables

This study investigated the relationships between serum testosterone level and selected physiological and personality variables in 58 males (21-61 years) before and after a four month physical fitness program consisting of jogging, calisthenics, and recreational activities. Physical fitness scores were obtained for each subject using a regression equation. Serum testosterone was determined using a radioimmunoassay technique. The multiple correlation was used to determine the relationship between serum testosterone and 19 independent variables consisting of age, height, and weight, and percent lean body weight, systolic and diastolic blood pressures, ten factors from the Cattell 16 PF and the three scales of the Eysenck Personality Inventory. A stepwise linear regression was used to identify the predictive power of each of the independent variables. The subjects improved significantly in physical fitness (p < 0.01). The multiple correlations both at the pre-test (R=0.77; R2=0.59) and post-test (R=0.67; R2=0.46) were significant at the 0.01 level. Neuroticism, factors dealing with emotional stability, aggression, and intelligence were powerful predictors initially. Similar results were obtained at the post-test except for the addition of percent lean as a powerful predictor and the absence of factors dealing with intelligence and aggression. The emergence of percent lean was seen to reflect changes in body composition associated with testosterone secretion. The absence of aggression at the post-test was interpreted in light of free catecholamine excretion associated with habitual exercise.     

Variation in anthropometric characters and their relationship with climatic factors: a study on the peoples of Arunachal Pradesh, India

In the present study an attempt has been made to examine the anthropometric variation and the relationship of anthropometric variables with climatic factors among the peoples of Arunachal Pradesh, India. The distance analysis does not seem to provide any interesting corroboration between anthropometric data and the intra- and intergroup relationship. A similar trend has also been noticed while analysing the correlation coefficient between two indices (i.e. the cephalic and total facial index). The present study suggests that the climatic factors are playing an important role in regulating the variation of anthropometric characters among the different population groups of Arunachal Pradesh.     

Autoregulatory factors of secondary metabolism and morphogenesis in actinomycetes

The Gram-positive bacterial genus Streptomyces possesses interesting biological aspects, such as the ability to produce a wide variety of secondary metabolites and a mycelial form of growth that culminates in sporulation. A close relationship of secondary metabolism and cell differentiation has been well recognized; secondary metabolism might be a physiological expression of cell differentiation. A variety of diffusible low-molecular-weight chemical substances have been found to function in general as regulatory factors, like "hormones" in eukaryotes, for secondary metabolism and cell differentiation. Among these factors, A-factor has been most extensively studied. This review summarizes recent research on the chemical structures, functions, biosyntheses, and mode of action of these regulatory factors.     

Reproductive and socioeconomic determinants of child survival: confounded, interactive, and age-dependent effects.

Studies of infant and child mortality have evolved to distinguish between two sets of explanatory variables-factors related to reproductive or maternal characteristics and socioeconomic factors, generally described as characteristics of the family or household. Almost all multivariate analyses include variables from each of these two sets, but there has been little consideration of the relationship between them. We examine how these two sets of variables jointly affect mortality. We test first for confounded effects by examining socioeconomic effects while excluding and then including reproductive variables in nested multivariate models. Next, we look for age-dependent effects among the explanatory variables and find that reproductive and socioeconomic factors affect mortality at differing ages of children. Finally, we examine interactive effects of the two sets of variables. We conclude that the higher mortality observed among the low status groups is not a result of greater concentration of poor reproductive patterns in those groups. Instead, higher status groups probably have more resources available for combating the negative effects of the same high-risk reproductive patterns.     

Seed size in tropical trees: a comparative study of factors affecting seed size in Peruvian angiosperms

Evolutionary comparative methods taking into account the potential effects of relatedness reveal that, among 202 species of animal-dispersed tropical woody angiosperms from Peru, large seeds may be an adaptation to: (1) dispersal by mammals rather than by birds and (2) greater plant height. Using the most powerful techniques currently available, appropriate comparisons were made between related species or species groups at all taxonomic levels, thus allowing use of all species in the data set. Even so, the results show no evidence of adaptation (i.e., a functional relationship) of seed mass to successional syndrome or to growth form (trees or vines). In previous cross-species analyses, seed mass has been linked to both of these ecological variables. The lack of relationship between seed mass and habitat use or growth form may be due to targeting the wrong trait to predict these two variables, or because seed mass is subject to exaptation, i.e., a particular seed mass has arisen for other reasons, but allows invasion into a habitat and currently serves to maintain that species in the habitat. Differentiation between these two explanations for the lack of correlation between seed mass and successional syndrome or growth form would entail species-by-species examination of the function of seed mass under natural conditions. The effect of relatedness on the ecological correlates of seed mass and plant height is determined for each of three taxonomic schemes. It is concluded that the three schemes do not differ greatly in the results obtained.     

Autoregulatory Factors of Secondary Metabolism and Morphogenesis in Actinomycetes

Abstract

The Gram-positive bacterial genus Streptomyces possesses interesting biological aspects, such as the ability to produce a wide variety of secondary metabolites and a mycelial form of growth that culminates in sporulation. A close relationship of secondary metabolism and cell differentiation has been well recognized; secondary metabolism might be a physiological expression of cell differentiation. A variety of diffusible low-molecular-weight chemical substances have been found to function in general as regulatory factors, like “hormones” in eukaryotes, for secondary metabolism and cell differentiation. Among these factors, A-factor has been most extensively studied. This review summarizes recent research on the chemical structures, functions, biosyntheses, and mode of action of these regulatory factors.     

Changes in the level of eosinophils, corticosterone and catecholamine metabolism in the dynamics of emotional-painful stress

A correlation has been established between changes in blood eosinophil content, corticosterone level and catecholamine metabolism during emotional painful stress. The authors assume that the differences in the functions of the adrenergic and pituitary-adrenal systems permit an objective determination of the parameters of stress formation in extremal exposures.     

What is driving the relationship between height and cognition? Evidence from the Twins Early Development Study

Taller children tend to have better cognitive ability, and the relationship between height and cognition has been proposed as an explanation for the height-wage labor market premium. Height-cognition associations may arise due to social factors that favor taller individuals or be driven by “common factors” that are correlated with height and cognition. Indeed, there is now evidence of a genetic correlation between height and cognition that provides specific evidence for this concern. We examine whether genetic factors explain the relationship by estimating associations between childhood height and cognition in the Twins Early Development Study. We find that height is associated with better cognition even after controlling for genetic and environmental factors shared by twins. The association between height and cognition within fraternal twin pairs is also robust to controlling for individual genetic predictors of height and cognition. These results suggest that genetic factors are not solely responsible for driving the relationship between height and cognition.     

Relationships between platelet and plasma monoamine oxidase,plasma dopamine-B-hydroxylase,and urinary 3-methoxy-4-hydroxy phenylglycol

The activity of dopamine-B-hydroxylase in blood has recently been demonstrated to be under genetic control and to correlate closely with urinary catecholamine excretion. The results of the present study did not demonstrate any relationship between a major catecholamine metabolite in urine, 3-methoxy-4-hydroxy phenylglycol, and dopamine-B-hydroxylase activity in plasma, monoamine oxidase activity in platelets, or monoamine oxidase activity in plasma. Differences in the origin of urinary catecholamines and urinary 3-methoxy-4-hydroxy phenyglycol may be responsible for these divergent results.     

Anthropometric and genetic distance between Gonds of Central India

A morphological and genetic study was undertaken on five Gondi-speaking populations of Central India (Andhra Pradesh and Maharashtra States). There has been no systematic biological study on this large Dravidian-speaking tribal group, 4 million in number, amounting to 13% of the total tribal population of India. Data was collected on 16 anthropometric measurements and seven genetic markers (blood groups, hemoglobin, G6PD and plasma protein polymorphisms) on the Raj Gonds, Kolams, Manne, Koyas and Plains Maria Gonds. Various genetic distance measures such as Mahalanobis's D2 and Nei's and Sanghvi's measures and cluster analysis techniques were used to determine the relationship between these groups based on anthropometrics and genetic variables. The statistical analysis revealed the Gonds to be a heterogenous group in both morphology and genetic characteristics. The morphological and genetic distances between these five groups when projected graphically revealed that the spatial distribution of these Gonds generally corresponds to their present geographical distribution. However, the actual relationships among each of the Gond populations show differences when based on these two biological variables, the possible reasons for this being discussed in the paper. The emphasis of this study is on the importance of geographical proximity in producing morphological and genetic similarity between populations, brought about by a short distance as well as similar geographical factors (such as soil, terrain, flora, etc.) drawing these populations together under a common ecocultural umbrella.     

Improved water retention links high species richness with increased productivity in arctic tundra moss communities

A positive relationship between plant species richness and ecosystem functioning has been found in a number of experimental studies. Positive species interactions at high species numbers have been suggested as a cause, but mechanisms driving positive interactions have not often been tested. In this experiment we asked three questions: (1) What is the relationship between species richness and productivity in experimentally constructed moss communities? (2) Is this relationship affected by plant density? and (3) Can changes in moisture absorption and retention explain observed relationships? To answer these questions we exposed arctic tundra moss communities of different species richness levels (1–11 species) and two different densities in the greenhouse to two levels of drought (short and long). Biomass (by the community and individual species), height and community moisture absorption and retention were measured as response variables. High species diversity increased productivity (more so in low-density plots than in high-density plots), but only when plots were watered regularly. Plot moisture retention was improved at high species richness as well, and plant height and variation in height was increased compared to plants in monoculture. Under high-density and short-drought conditions 10 out of 12 species grew better in mixture than in monoculture, but under the long drought treatment only six species did. A positive feedback loop between biomass and improved humidity under high diversity was supported by path analysis. We conclude that in this community the relationship between species richness and productivity depends on moisture availability and density, with improved water absorption and retention likely to be the mechanism for increased plant growth when drought periods are short. Furthermore, since this is the opposite of what has been found for temperate moss communities, conclusions from one system cannot automatically be extrapolated to other systems.     

The role of psychological variables in the development of somatic diseases--proposal of the integrational model

The author discusses three groups of the distinguishable results of investigations which confirm the relationship between psychological factors and the development of the somatic diseases such as: changing situations, personality and temperamental factors, and behaviour pattern A. The author quotes data indicating that perceptional and emotional patterns together with associated patterns of the physiological responses may play an important role among personality and temperamental variables. Integrational model includes, besides psychological variables, other (biological) risk factors. Hypotheses concerning the mechanism mediating between these variables and the development of the disease are also discussed.     

植物生长抽梢期和气候因子对株高生长影响

利用西双版纳热带植物园的热带植物物候观测资料和气候资料,通过对热带植物株高生长偏差、生长抽梢期和气候因子的分析,探讨了三者的关系。结果表明,热带植物生长抽梢期变长不一定影响株高生长,而且与株高生长偏差的关系也小于气候因子与株高生长偏差的关系。同时,热带植物生长抽梢期对气候因子和株高生长偏差之间关系的贡献很小。因此,可以认为热带植物的生长期对植被生产力的促进作用较弱。     

Secular trend in height in Al Ain-United Arab Emirates

Correlation between cycles in human stature and those in economic variables is well established. A recent review of international trends in this area provided information from most parts of the world but none on Arabs in the Middle East or more specifically the gulf region.The United Arab Emirates experienced a transformation in economic and social life followed the discovery of oil in the late 1960s and the wealth that it generated. No data is available on human growth at this period of time because its population never had health services prior to the 1970s. A study on conventional cardiovascular risk factors in 2004-2005 included 817 randomly selected national adults (≥18 years) from both genders. The relationship between height and age in this study showed both men and women have increased in height with time demonstrating the secular change in height most likely a result of changing socioeconomic factors.     

Effect of the rate of blood loss on the plasma catecholamine response

In the present experiments the influence on the sympatho-adrenal system of the rate of haemorrhage-induced blood pressure fall in dogs was studied by measuring the plasma catecholamine response. Bleeding to a mean arterial pressure of 5.3 kPa in either 10 or 40 minutes caused an identical increase in the plasma catecholamine level. Similarly, there was no difference in bleeding volumes between the two groups. Within these limits the magnitude of the early catecholamine response was independent of the rate of the haemorrhage-induced decrease of blood pressure. The magnitude of the sympatho-adrenal response depended on the amount of lost blood. Bleeding for 80 minutes to the same pressure resulted in a considerably larger loss of blood and higher plasma catecholamine levels. No relationship was, however, found between the extent of the catecholamine response and the amount of the bleeding volume, probably due to some interaction with other control mechanisms.