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1.
Bruno David 《Geobios》1981,14(6):795-799
Three species of irregular see-urchins form the settlement of a marly level (lower Hauterivian) of the Castellane area. Two of them are strongly smaller than the norm. Their stunting is prouved by ontogenic, mecanical, sedimentological and ecological arguments. The ecological grounds of stunting are discussed.  相似文献   
2.
Malnutrition in school-age children is common in developing countries and includes both stunting and underweight. Stunting, which represents a chronic state of nutritional stress, leads to adverse health, educational and cognitive effects. Although much research is focused on preschool-age children, recent studies show both the high prevalence of stunting and the effectiveness of interventions in school-age children. The objectives of the current study were to determine the risk factors for stunting only, and stunting and underweight. A survey was conducted in 1074 grade 5 children (mean age 10 years) from 17 schools in Belen, Peru, a community of extreme poverty. Prevalence of underweight and stunting were 10.5 and 34.5%, respectively, co-prevalence was 9.3%. Based on multivariable logistic regression analyses, significant independent risk factors (odds ratio: OR) for stunting and underweight were: age (per 1 year increment) (OR=1.55; 95% confidence interval (CI): 1.33, 1.81); diarrhoea in the last week (OR=1.96; 95% CI: 1.17, 3.29) and hookworm infection (OR=1.74; 95% CI: 1.05, 2.86). Significant independent risk factors for stunting only were: age (per 1 year increment) (OR=1.51; 95% CI: 1.35, 1.70); anaemia (OR=1.98; 95% CI: 1.26, 3.11); and moderate and heavy Trichuris and Ascaris co-infection (OR=1.95; 95% CI: 1.35, 2.82). Our results indicate a high prevalence of stunting, in addition to other adverse health indicators, in the study population. Due to the interrelation between many of these health and nutrition problems, interventions at both the school and community levels, including de-worming, feeding programs and health and hygiene education, are needed to reduce malnutrition in this and other similar populations living in conditions of extreme poverty.  相似文献   
3.
Synopsis In dense, single-species assemblages of crucian carp, competition is intense and results in populations of stunted fish. To explore mechanisms underlying this competition, we measured handling times, return rates, and prey choice for five sizes of crucian carp feeding on six sizes of a standardized food. Handling times increased with prey size and decreased with fish size. Return rates (dry mass ingested per unit handling time) increased dramatically with fish size, and generally decreased with increasing prey size, especially for small fish. Patterns of return rates among size-classes suggested that one or more size-related shifts in feeding efficiency exist for crucian carp; combined with physiological stresses related to winter anoxia, the inability of fish to make these shifts may contribute to size structures observed in high-density populations. Comparisons of relations among fish size, prey size, and return rates for crucian carp and bluegill, Lepomis macrochirus, suggest that similar intraspecific competitive relations exist between generalist species with size-structured populations. Despite differences in return rates among prey sizes, the extent of food selectivity based on prey size exhibited by crucian carp in two types of choice trials was less than predicted. Crucian carp commonly take in several items before mechanically processing food with their pharyngeal apparatus; this multiple prey processing may contribute to disparities between observed choice patterns and those predicted based on return rates for single prey.  相似文献   
4.
The quick-release technique to estimate musculotendinous (MT) stiffness has been extensively used over the last years, in both animals and humans, to gain insights in the adaptive process of the series elastic component (SEC). Recently, MT stiffness quantification, i.e., SEC behavior, has been revisited for subjects not able to fully activate their muscles (effects of long-term spaceflight or non-mature muscles). Such a phenomenon can also be encountered in stunted children. So, the aim of the present study was to analyze the effect of stunting on MT stiffness taking into account possible defect in muscle activation. For this study, 20 eutrophic children (EU) with an average age of 9 years ± 4 months were compared to 11age matched stunted children (S) evaluated by the height-to-age index. The MT stiffness index was obtained with regard to stiffness–torque and stiffness–soleus EMG relationships. The children of the S group presented a significantly lower Maximal Voluntary Contraction (MVC) in plantar flexion in comparison with children of the EU group (?37.8%). The significantly lower MT stiffness index for S children (?42.6%) was evidenced only when quantified with regard to the stiffness–soleus EMG relationship (66.5 ± 42.8 vs. 38.2 ± 19.9 Nm rad?1%?1). Possible delay in fiber type differentiation or tendinous structure maturation can account for the lower MT stiffness index in S children. In conclusion, stunting during early childhood delays the differentiation and maturation processes of musculotendinous structures as shown by the lower MT stiffness quantified with regards to muscle activity, also altered for stunted prepubertal children.  相似文献   
5.
We undertake two calculations, one for all developing countries, the other for 34 developing countries that together account for 90% of the world’s stunted children. The first asks how much lower a country’s per capita income is today as a result of having a fraction of its workforce been stunted in childhood. We use a development accounting framework, relying on micro-econometric estimates of the effects of childhood stunting on adult wages through their effects on years of schooling, cognitive skills, and height, parsing out the relative contribution of each set of returns to avoid double counting. We estimate that, on average, the per capita income penalty from stunting is between 5–7%, depending on the assumption. In our second calculation we estimate the economic value and the costs associates with scaling up a package of nutrition interventions using the same methodology and set of assumptions used in the first calculation. We take a package of 10 nutrition interventions that has data on both effects and costs, and we estimate the rate-of-return to gradually introducing this program over a period of 10 years in 34 countries that together account for 90% of the world’s stunted children. We estimate a rate-of-return of 12%, and a benefit-cost ratio of 5:1-6:1.  相似文献   
6.
This study investigates the relationship between household wealth and child height utilizing longitudinal data on 7150 children from Ethiopia, India, Peru, and Vietnam. The concept of conditional wealth is applied to separate the influence of wealth in early childhood. Conditional wealth is the change in wealth that was unpredicted at the age of 5 years. This study finds two dimensions of heterogeneity in the wealth-gradient of adolescent height: gender and stunting status at the age of 5 years. For all four countries in the study, the effect of conditional wealth on adolescent height is stronger for boys than for girls. The estimates for the pooled sample indicate that after the age of 5 years, the growth of children who were stunted at that age is significantly more responsive to conditional wealth than the growth of non-stunted children. The analysis results show that for boys in Ethiopia, a one-standard-deviation increase in preadolescence wealth is associated with an increase of 1 cm (standard error [SE]: 0.3) in height at the age of 15 years. For boys in the Indian state of Andhra Pradesh, Peru, and Vietnam, the corresponding figures are 1.1 cm (SE: 0.4), 1.8 cm (SE: 0.4), and 1.2 cm (SE: 0.4), respectively. The effect of preadolescence wealth on adolescent height is not statistically significant for girls, except in some regions. Overall, the results suggest that household wealth in preadolescence disproportionately benefits the male population in these countries when using height as a proxy for health.  相似文献   
7.
Between 1997 and 2012, Paraguay achieved not only remarkable improvements in child nutrition, but also a surprising elimination of the rural-urban differential in child height-for-age Z score (HAZ) and stunting. Our decomposition analysis, applied to four rounds of Paraguayan National Household Surveys, allows us to directly infer not only the contributions of changes in determinants of child nutritional status to the improvements in child nutritional status in rural and urban areas, but also their contribution to closing the rural-urban gap. We find that while common determinants of child nutritional status such as income, maternal education, sanitation, and access to piped water are strongly associated with improvements in child nutrition, they have contributed little to reducing the rural-urban gap (10%, p < 0.05). Improvements in health care utilization, family planning, and demographics have been the main drivers in closing the rural-urban gap in child nutritional status in Paraguay (32%, p < 0.05). The results highlight the potential need for multipronged nutritional strategies that consider the distinct needs of rural and urban communities.  相似文献   
8.
The economic transition in developing countries is not always the result of the change from a centrally-planned to a free-market economy, but may be found within an already existing free-market economy as a result of profound political change, as in South Africa. The release of Nelson Mandela in February 1990 heralded an end both to the political system of apartheid and to the concomitant social, political, and economic disenfranchisement of 30 million non-White people in South Africa. The first freely elected non-White government came to power in 1994 and initiated a number of social and economic reforms aimed at alleviating the worst consequences of apartheid. This paper examines the effect of post-apartheid economic and social transition on the growth and development of urban children. Over 4000 children born in Soweto and Johannesburg were enrolled in the Birth to Ten (BTT) birth-cohort study in 1990. Whilst these children were born with lower birth weights than in developed countries, they did grow strongly in infancy, particularly in weight, to reflect normal reference values for body mass index (BMI) by 1 year of age. While post-apartheid social and economic changes were expected to take some time to affect child growth and development, the rate of change has been slower than expected. Data from the BTT study demonstrate that the growth of White children continues to be superior to that of their non-White peers and differences that existed at birth and during infancy have not diminished during childhood and early adolescence. Whatever factors are changed at the national or community levels during economic (and social) transition in South Africa appear not yet to have resulted in improved child physical growth.  相似文献   
9.
As measured by degree of stunting, close to half of India's children suffer from chronic malnutrition and about a quarter from severe chronic malnutrition. Data from the 1998-1999 National Family Health Survey (NFHS) are analysed to assess whether recommended infant feeding practices help to alleviate the prevalence of stunting. The evidence supports some recommended practices, including the advice that mother not squeeze the colostrum from her breasts, not use a feeding bottle with a nipple, exclusive breastfeeding for the first 4-6 months and feeding supplementary foods (solids and mushy foods) at about 7 months, and suggests that, for some children, better feeding practices could reduce the prevalence of severe stunting by up to 30%. The paper also examines a range of other issues related to stunting--whether medical supplementations and inoculations have an effect, whether mothers more actively involved in health decisions have less stunted children, and the links between stunting, diarrhoea and anaemia. An explanation is offered for the positive relationship between using oral rehydration salts and stunting.  相似文献   
10.
Orphans who lack household or community support face significant socio-economic disadvantages. In particular, they are at greater risk of malnutrition and stunting in developing countries. Children who have no living parents, also called double orphans, are most likely to require support from extended families or public institutions. This paper explores how WASH infrastructure, and public health and social services relate to stunting. It is one of the first studies to analyse these factors with a specific focus on double orphans, who tend to live in under-serviced areas with high stunting rates and poor access to public resources. We collate a cross sectional spatial dataset with local child stunting rates from 2013, rates of double orphanhood, private household resources, and public services from 2011 for South Africa, a country where the HIV/AIDS pandemic has led to high rates of double orphanhood. We estimate spatial econometric models that account for unobserved regional shocks and measurement bias, but which do not address other biases. Our results show that high stunting rates, particularly in areas with high proportions of double orphans, overlap strongly with poor provision of WASH and the availability of household resources. By contrast, other softer services accessed outside the home, such as access to health, social welfare and early childhood development facilities are not correlated with stunting in the same way. WASH is more strongly related to reduced stunting when infrastructure covers larger geographic areas and with the combined use of services from adjacent areas. This occurs because of economies of scale in provision and preventing transmission of disease across regions. Policy makers can explore the option to reduce stunting by expanding geographic networks of WASH service delivery into under-serviced areas where double orphans tend to locate.  相似文献   
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