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1.
A consensus has been forged in the last decade that recent periods of sustained growth in total factor productivity and reduced poverty are closely associated with improvements in a population's child nutrition, adult health, and schooling, particularly in low-income countries. Estimates of the productive returns from these three forms of human capital investment are nonetheless qualified by a number of limitations in our data and analytical methods. This paper reviews the problems that occupy researchers in this field and summarizes accumulating evidence of empirical regularities. Social experiments must be designed to assess how randomized policy interventions motivate families and individuals to invest in human capital, and then measure the changed wage opportunities of those who have been induced to make these investments. Statistical estimation of wage functions that seek to represent the relationship between wage rates and a variety of human capital stocks may yield biased estimates of private rates of return from these investments for a variety of reasons. The paper summarizes several of these problems and illustrates how data and statistical methods can be used to deal with some of them. The measures of labor productivity and the proxies specified for schooling and adult health are first discussed, and then the functional relationships between human capital and wages are described. Three types of estimation problem are discussed: (1) bias due to omitted variables, such as ability or frailty; (2) bias due to the measurement of an aggregation of multiple sources of human capital, e.g. genetic and socially reproducible variation, which may contribute to different gains in worker productivity; and (3) errors in measurement of the human capital stocks. Empirical examples and illustrative estimates are surveyed.  相似文献   

2.
Three highly heterogeneous haemoglobin phenotypes, each composed of 22 different haemoglobin components, were identified among 17 West African populations of Sarotherodon melanotheron . Natural populations from (1) Senegal, (2) Ivory Coast/Ghana/Togo/Benin, and (3) Congo were distinguished. The heterogeneity and specificity of these respiratory pigments was based on genetic variations at the globin chain coding loci. In total, five different α-chains and four different β-chains were detected by acidic urea polyacrylamide gel electrophoresis (PAGE). Combinations of α-chains were characteristic for populations in (1) Senegal, (2) Ivory Coast, (3) Ghana/Togo/Benin, and (4) Congo. Pronounced variations at the β-globin chain cluster were found by acidic urea triton PAGE. Cladistic analyses of the globin chain characteristics confirmed the validity of the following taxonomic units previously ranked as sub-species: (1) populations from Ivory Coast, Ghana, Togo and Benin belong to the sub-species S. m. melanotheron ; (2) populations from Senegal form genetically a separate cluster representing the sub-species S. m. heudelotii ; (3) the Congo population, morphologically considered to represent the sub-species S. m. nigripinnis , forms another distinct unit; but there was no evidence of S. m. paludinosus within the samples from Senegal.  相似文献   

3.
Child malnutrition is pervasive in developing countries and anthropometric measures such as weight-for-height and height-for-age have proven reliable indicators of short term malnutrition and stunting. Rather than studying these indicators separately, we look at their interaction and carve out child health dynamics. Considering height-for-age a child's health stock and weight-for-lagged height a proxy for nutritional inputs, we develop a child health production function that features self-productivity of past health stocks and contemporaneous nutritional inputs. We test the model on a Senegalese panel of 271 children between 0 and 5 years employing dynamic panel methods to control for endogeneity in the production function. In line with previous evidence, we find that children can partially catch-up from malnutrition spells. Yet, child health stocks also deplete quickly and need constant updating in the form of nutrition. This demonstrates the importance of health memory and that malnutrition cannot be fought with snapshot interventions. Consequently, sustainable nutrition interventions have to be long term and yield higher returns the earlier they reach children.  相似文献   

4.

Purpose

Life cycle assessments (LCAs) are considered common quantitative environmental techniques to analyze the environmental impact of products and/or services throughout their entire life cycle. A few LCA studies have been conducted in West Africa. This study aimed to discuss the availability of LCA (and similar) studies in Nigeria, Ghana, and Ivory Coast.

Methods

An online literature review of reports published between 2000 and 2016 was conducted using the following keywords: “life cycle assessment,” “carbon footprinting,” “water footprinting,” “environmental impact,” “Nigeria,” “Ghana” and “Ivory Coast.”

Results and discussion

A total of 31 LCA and environmental studies in Nigeria, Ghana, and Ivory Coast were found; all but one were conducted after 2008. These were mainly academic and most were publicly available. The industries studied included energy sector, waste management, real estate, food sector, and others such as timber and gold. The minimal number of studies on LCAs and environmental impacts in these West African states could be because companies are failing to promote quantitative environmental studies or studies are kept internally for the use of other assessment techniques. Furthermore, it could be that academic research institutions lack cutting-edge research resources for LCA, environmental impact, carbon, and water footprinting studies.

Conclusions

Further quantitative environmental studies should be conducted in Nigeria, Ghana, and Ivory Coast to increase the understanding of environmental impacts. In these countries, the existence of LCA studies (and by association the localized life cycle inventory (LCI) datasets) is crucial as more companies request this information to feed into background processes.
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5.
6.
Miss Waldron’s red colobus (Procolobus badius waldroni) has a restricted distribution in eastern Ivory Coast and western Ghana. There have been no confirmed sightings of them since 1978 and surveys carried out from 1993 to the present have yet to reveal any living individual. Since the announcement of the monkey’s probable extinction (Oates et al., 2000), new evidence from forest in the extreme southeast of Ivory Coast suggests that a handful of individuals have remained undetected to this point. I discuss the evidence—a tail, a skin and a photograph—and results of accompanying surveys. Additional surveys of the Ehy Forest are required to confirm the presence of Procolobus badius waldroni and an Action Plan for the conservation of all red colobus across the continent is needed to prevent the disappearance of other taxa.  相似文献   

7.
In the first half of the XXth century, while Upper-Volta (now Burkina Faso) was suffering a terrible epidemic of sleeping sickness, the French colonial administration encouraged the movement of people from Upper-Volta to Ivory Coast to meet their demands for labour. This led to the establishment of Mossi villages, such as those of Koudougou, in the Ivorian forest with populations originating from areas of Upper-Volta that were not only densely populated but also severely affected by sleeping sickness. Since 2000, most cases of sleeping sickness in the Koudougou district of Burkina Faso have been in people originally from Ivory Coast. Who are they? Where did they settle in Burkina Faso? Where do they come from in Ivory Coast? After having retraced the epidemiological history of Koudougou villages in Burkina Faso and Ivory Coast, the history of ten cases of sleeping sickness detected passively at Koudougou hospital since 2000 were analysed. All cases originated from the forest area of Ivory Coast. Understanding the spread of sleeping sickness between Burkina Faso and Ivory Coast will assist in the identification of areas of disease risk.  相似文献   

8.
Synopsis Similarities between the freshwater fish faunas of 52 west African rivers have been investigated and three main zoogeographic regions recognized. The Sudanian region includes all rivers from Senegal to the Omo, as well as coastal basins from Ivory Coast to the Cross and the Wouri. The Upper Guinean region comprises the coastal basins from Guinea to Liberia and the Lower Guinean one, the coastal rivers of Cameroon and Gaboon. The Sudanian region can be sub-divided into a Sudanian region sensu stricto, including the Sahelo-Sudanese rivers, and the Eburneo-Ghanean region corresponding to coastal basins from the Cess (or Nipoué, Ivory Coast) to the Pra (Ghana). These delimitations give an highly significant within region faunal homogeneity, even if the effect of geographical proximity between rivers is removed. 21 to 71% of the fish species in each region are endemics. The present patterns of distribution are the result of past climatic and geological events affecting west Africa and, given this framework, the role of alternating wet and dry periods during the early Quarternary is emphasized as well as the importance of mountains as dispersal barriers. Role of recent river connections and links via lagoon is emphasized in explaining river faunal similarities within biogeographical regions.  相似文献   

9.
Fecundability and husband's age   总被引:3,自引:0,他引:3  
The effect of husband's age on the probability of conception is evaluated from World Fertility Survey data in five developing countries: the Ivory Coast, Ghana Kenya, the Sudan, and Syria. Proportional hazards models, which include wife's age, husband's age, marriage duration, union type, and post-partum exposure as covariates, are used to describe the monthly conception rate for second and higher-order birth intervals in which no contraception was used. With the exception of Syria, the resulting models indicate that the effects of male age are generally small in relation to the influences of marital duration and the age of the woman.  相似文献   

10.
An epidemiological study was carried out in 2004-2005 at the anti-tuberculosis centre of Divo (Ivory Coast) to collect sera from patients who consulted for tuberculosis suspicion and to estimate the seroprevalence of human paragonimosis in the context of a systematic screening. No Paragonimus egg was found in the stools and/or sputa of the 167 persons investigated. In contrast, 41 sera were ascertained with antibodies against Paragonimus africanus using ELISA testing. As the optical density (OD) values related to seropositive findings were found under 0.6 (the minimal OD to detect an active paragonimosis), the above antibody titres might originate from patients in chronic or in convalescent stages, or might result of cross reactions with trematodes. Concomitantly, dissection of local crabs (Callinectes marginatus) demonstrated the presence of Paragonimus metacercariae in six out of 34 examined. The parasite burdens in crabs ranged from two to 35 cysts with a mean diameter of 302 microm. In Ivory Coast, the locality of Divo must be considered an at-risk zone in reason of the presence of anti-Paragonimus antibodies in several human sera and the presence of infected crabs at the local market.  相似文献   

11.
A new species of the chromidotilapiine genus Thysochromis, is described from the Noumbi and Kouilou River drainages in the Republic of Congo. Based on the current investigation, Thysochromis is resolved as containing two geographically disjunct species, T. ansorgii from localities in the upper Guinean ichthyofaunal province (Ivory Coast, Ghana, Benin and Nigeria) and Thysochromis emili sp. nov. restricted to coastal regions of the Republic of Congo in the lower Guinean province.  相似文献   

12.

Background  

We investigated genetic variation of a major histcompatibility complex (MHC) pseudogene (Anvi -DAB1) in the little greenbul (Andropadus virens) from four localities in Cameroon and one in Ivory Coast, West Africa. Previous microsatellite and mitochondrial DNA analyses had revealed little or no genetic differentiation among Cameroon localities but significant differentiation between localities in Cameroon and Ivory Coast.  相似文献   

13.
This paper analyses earning/wage differentials by height among coalmine workers in India. Our findings suggest that workers of above average height earn 9-17% more than their shorter counterparts and 6-13% more than average reference height. The results suggest that long-term investments in health human capital might ensure increase of labour productivity and thereby earnings, particularly in underdeveloped economies.  相似文献   

14.
Two series of plankton samples, collected in different parts of the Ivory Coast, are examined for their rotifer content. Seventy-one taxa are identified to species level, some of which are present in different forms. Seventeen taxa are new to the Ivory Coast, three are new to Africa. Ecological and distributional notes are given. The correct spelling of Brachionus quadridentatus f. melhemi is discussed.  相似文献   

15.
Analysis of Mycobacterium tuberculosis strains was carried out using isolates collected from 69 Senegalese and 20 Ivory Coast tuberculosis patients. These 89 isolates were typed by means of the spoligotyping technique, showing clusterized populations of bacterial strains. In the Senegalese patients, 35 genetic profiles were observed with 10 clusters of spoligotypes from 44 isolates. Among Ivory Coast patients, 11 spoligotypes were found for 20 isolates. A particular cluster of isolates was evident both in Senegalese (10) and Ivory Coast (11) patients. These results show the existence of polymorphism of the direct repeat region for African M. tuberculosis strains. However they suggest that additionnal markers are needed for accurate epidemiological studies in areas that are highly endemic for tuberculosis.  相似文献   

16.
A new species, Epistemma neuerburgii is described. This species was discovered in the Nyungwe National Park, Rwanda, Tropical Africa during a field investigation of epiphytes in montane rainforest. It was, however, also found in Uganda, in similar environment. E. neuerburgii is the fourth species described for Epistemma, but the other three species are found about 2000 km to the west in Cameroon, Gabon, Ghana, Ivory Coast and Nigeria. E. neuerburgii is an epiphytic climber distinguished by fairly large lanceolate leaves and conspicuous reddish-purple flowers with corolline white, densely hairy corona lobes.  相似文献   

17.
This paper quantifies the relationship between risk aversion and discount rates on the one hand and height and weight on the other. It studies this link in the context of poor households in Cambodia. Evidence is based on an original dataset that contains both experimental measures of risk taking and impatience along with anthropometric measurements of children and adults. The aim of the paper is to (i) explore the importance of risk and time preferences in explaining undernutrition and (ii) compare the evidence stemming from poor households to strikingly similar findings from industrialized countries. It uses an inter-generational approach to explain observed correlations in adults and children that is inspired by the height premium on labor markets. Parents can invest in the health capital of their child to increase future earnings and their consumption when old: better nutrition during infancy translates into better human capital and better wages, and ultimately better financial means to take care of elderly parents. However this investment is subject to considerable uncertainty, since parents neither perfectly foresee economic conditions when the child starts earning nor fully observe the ability to transform nutritional investments into long-term health capital. As a result, risk taking households have taller and heavier children. Conversely, impatience does not affect child health. In the case of adults, only weight and the body mass index (BMI), but not height, are positively and moderately correlated with risk taking and impatience.  相似文献   

18.
Many studies of quantitative and disease traits in human genetics rely upon self-reported measures. Such measures are based on questionnaires or interviews and are often cheaper and more readily available than alternatives. However, the precision and potential bias cannot usually be assessed. Here we report a detailed quantitative genetic analysis of stature. We characterise the degree of measurement error by utilising a large sample of Australian twin pairs (857 MZ, 815 DZ) with both clinical and self-reported measures of height. Self-report height measurements are shown to be more variable than clinical measures. This has led to lowered estimates of heritability in many previous studies of stature. In our twin sample the heritability estimate for clinical height exceeded 90%. Repeated measures analysis shows that 2–3 times as many self-report measures are required to recover heritability estimates similar to those obtained from clinical measures. Bivariate genetic repeated measures analysis of self-report and clinical height measures showed an additive genetic correlation >0.98. We show that the accuracy of self-report height is upwardly biased in older individuals and in individuals of short stature. By comparing clinical and self-report measures we also showed that there was a genetic component to females systematically reporting their height incorrectly; this phenomenon appeared to not be present in males. The results from the measurement error analysis were subsequently used to assess the effects of error on the power to detect linkage in a genome scan. Moderate reduction in error (through the use of accurate clinical or multiple self-report measures) increased the effective sample size by 22%; elimination of measurement error led to increases in effective sample size of 41%.  相似文献   

19.
Using pooled children data from the 1998 and 2003 Ghana Demographic and Health Surveys, this study examines religious differences in child survival in Ghana. Guided by the particularized theology and selectivity theses, a piecewise constant hazard model with gamma-shared frailty is used to explore if there are denominational differences in child mortality, and whether these could be explained through other characteristics. At the bivariate level, children whose mothers identified as Muslim and Traditional were found to have a significantly higher risk of death compared with their counterparts whose mothers identified as Christians. In the multivariate models, however, the religious differences disappeared after the mediating and confounding influence of socioeconomic factors were controlled. The findings provide support for the selectivity hypothesis, which is based on the notion that religious variations mainly reflect differential access to social and human capital rather than religious theology per se.  相似文献   

20.
The prevalence of health problems and malnutrition in Bolivia is exceptionally high, even in comparison to other underdeveloped countries. This study analyzes the relationship between a two measures of child health--height-for-age and weight-for-age z-scores--and a set of physical and cultural determinants of child nutrition, including mother's characteristics, household assets and access to public services. The ultimate aim is to identify the most important determinants of child health and to measure the relative impact of each factor on the height and weight z-scores. A sequential strategy was adopted in order to estimate a two-equation linear model with correlated error terms. A major finding points to geographical and cultural variables as main causes of nutritional status and highlights the role of mother's anthropometrical characteristics. This study uses data on over 3000 children gathered from a Demographic and Health Survey (DHS).  相似文献   

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