483 research outputs found
Gender discrimination and its impact on income, productivity, and technical efficiency: evidence from Benin
This paper examines the occurrence and impact of gender discrimination in access to production resources on the income, productivity, and technical efficiency of farmers. Through an empirical investigation of farmers from Koussin-Le´le´, a semi-collective irrigated rice scheme in central Benin, we find that female rice farmers are particularly discriminated against with regard to scheme membership and access to land and equipment, resulting in significant negative impacts on their productivity and income. Although women have lower productivity, they are as technically efficient as men. The findings suggest that there is considerable scope for improving the productivity of women through increasing their access to production resources
Can Africa replicate Asia's green revolution in rice ?
Asia's green revolution in rice was transformational and improved the lives of millions of poor households. Rice has become an increasingly important part of African diets and imports of rice have grown. Agronomists point out that large areas in Africa are well suited for rice and are encouraged by the field tests of new rice varieties. So is Africa poised for its own green revolution in rice? This study reviews the recent literature on rice technologies and their impact on productivity, incomes, and poverty, and compares current conditions in Africa with the conditions that prevailed in Asia as its rice revolution got under way. An important conclusion is that, to a degree, a rice revolution has already begun in Africa. Moreover, many of the same practices that have proved successful in Asia and in Africa can be applied where yields are currently low. At the same time, for many reasons, Africa's rice revolution has been, and will continue to be, characterized by a mosaic of successes, situated where the conditions are right for new technologies to take hold. This can have profound effects in some places. But because diets, markets, and geography are heterogeneous in Africa, the successful transformation of the Africa's rice sector must be matched by productivity gains in other crops to fully launch Africa's Green Revolution.Agricultural Research,Crops&Crop Management Systems,Climate Change and Agriculture,Food&Beverage Industry,Agricultural Knowledge&Information Systems
Pauvreté et distribution de revenus au Sénégal: une approche par la modélisation en équilibre général calculable micro-simulé
La nouvelle orientation de la politique économique au Sénégal vise à accroître les revenus des pauvres et à attaquer la pauvreté là où elle est principalement localisée. La stratégie de réduction de la pauvreté va être mise en oeuvre dans un contexte de libéralisation des échanges commerciaux internationaux notamment dans le secteur agricole. Dans ce contexte, nous avons développé un modèle d'équilibre général calculable micro-simulé multi-ménages du type Decaluwé et al. (1999) permettant d'évaluer l'impact que pourront avoir ces politiques agricoles à l'échelle des ménages et de faire le lien entre ces réformes économiques, la pauvreté et la distribution de revenu. Ce modèle offre beaucoup de flexibilité en permettant notamment de modifier la distribution des groupes cibles qui n'ont pas à être revenus avant l'exercice de simulation afin d'effectuer l'analyse de pauvreté et d'inégalité ex post à l'exercice de modélisation. Dans ce travail, nous avons également comparé les effets en terme d'analyse de pauvreté et d'inégalité entre une distribution paramétrique (Dagum, 3 paramètres) et une distribution non-paramétrique et montré que ce choix engendrait des différences significatives quant aux effets sur la pauvreté. Contrairement aux applications faite par Decaluwé et al. (1999) et Cockburn (2002) au Népal, les impacts sur la pauvreté sont assez importants, ce qui montre que cette approche offre un outil riche permettant d'évaluer l'impact de politiques économiques ou chocs externes sur la pauvreté et la distribution de revenu.Modèle d'équilibre général calculable, micro-simulation, analyse de pauvreté, distribution de revenu
African baobabs with a very large number of stems and false stems : radiocarbon Investigation of the baobab of Warang
Author Posting. © Studia Chemia, 2017. This article is posted here by permission of Studia Chemia for personal use, not for redistribution. The definitive version was published in Studia Universitatis Babes-Bolyai, Seria Chemia 62, no. 1 (2017): 111-120, doi:10.24193/subbchem.2017.1.09.The article presents the AMS (accelerator mass spectrometry) radiocarbon dating results of the baobab of Warang, Senegal. The investigation of the baobab revealed that it consists of 18 partially fused stems, which represents the largest number of stems reported for an African baobab. Three stems build the ring that closes a false cavity, while 15 stems grow outside the ring. Seven wood samples were collected from the false cavity and from the outer part of other stems. The dating results evinced that the stems belong to four different generations, out of which the first generation is around 500 years old. We also documented the presence of false stems, which emerge from a large adjacent stem, are triangular in horizontal section and act as an anchor. The baobab of Warang possesses 12 ordinary stems and 6 false stems.The research was funded by the
Romanian Ministry of National Education CNCS-UEFISCDI under grant
PN-II-ID-PCE-2013-76
PIP5KIβ Selectively Modulates Apical Endocytosis in Polarized Renal Epithelial Cells
Localized synthesis of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] at clathrin coated pits (CCPs) is crucial for the recruitment of adaptors and other components of the internalization machinery, as well as for regulating actin dynamics during endocytosis. PtdIns(4,5)P2 is synthesized from phosphatidylinositol 4-phosphate by any of three phosphatidylinositol 5-kinase type I (PIP5KI) isoforms (α, β or γ). PIP5KIβ localizes almost exclusively to the apical surface in polarized mouse cortical collecting duct cells, whereas the other isoforms have a less polarized membrane distribution. We therefore investigated the role of PIP5KI isoforms in endocytosis at the apical and basolateral domains. Endocytosis at the apical surface is known to occur more slowly than at the basolateral surface. Apical endocytosis was selectively stimulated by overexpression of PIP5KIβ whereas the other isoforms had no effect on either apical or basolateral internalization. We found no difference in the affinity for PtdIns(4,5)P2-containing liposomes of the PtdIns(4,5)P2 binding domains of epsin and Dab2, consistent with a generic effect of elevated PtdIns(4,5)P2 on apical endocytosis. Additionally, using apical total internal reflection fluorescence imaging and electron microscopy we found that cells overexpressing PIP5KIβ have fewer apical CCPs but more internalized coated structures than control cells, consistent with enhanced maturation of apical CCPs. Together, our results suggest that synthesis of PtdIns(4,5)P2 mediated by PIP5KIβ is rate limiting for apical but not basolateral endocytosis in polarized kidney cells. PtdIns(4,5)P2 may be required to overcome specific structural constraints that limit the efficiency of apical endocytosis. © 2013 Szalinski et al
The impact of credit constraints on the adoption of hybrid maize in Malawi
This paper investigates the impact of credit constraints on the adoption of hybrid maize among rural households in Malawi. To address the endogenous and binary nature of the household's credit constraints status, we employ a treatment-effects model to consistently estimate the effect of credit constraints. Results reveal that after effectively correcting for endogeneity, credit constraints have a negative and significant effect on the amount of land allocated to hybrid maize. Results also show that farmers with larger land holdings allocate more land to hybrid maize. Although less likely to report credit constraints, older farmers allocate less land to hybrid maize than younger farmers. These findings suggest that there is scope for increasing the cultivation of hybrid maize in Malawi if credit is targeted at younger farmers that are credit-constrained
Postpartum maternal morbidity requiring hospital admission in Lusaka, Zambia – a descriptive study
Background: Information on the extent of postpartum maternal morbidity in developing countries is extremely limited. In many settings, data from hospital-based studies is hard to interpret because of the small proportion of women that have access to medical care. However, in those areas with good uptake of health care, the measurement of the type and incidence of complications severe enough to require hospitalisation may provide useful baseline information on the acute and severe morbidity that women experience in the early weeks following childbirth. An analysis of health services data from Lusaka, Zambia, is presented. Methods: Six-month retrospective review of hospital registers and 4-week cross-sectional study with prospective identification of postpartum admissions. Results: Both parts of the study identified puerperal sepsis and malaria as, respectively, the leading direct and indirect causes of postpartum morbidity requiring hospital admission. Puerperal sepsis accounted for 34.8% of 365 postpartum admissions in the 6-month period. Malaria and pneumonia together accounted for one-fifth of all postpartum admissions (14.5% & 6% respectively). At least 1.7% of the postpartum population in Lusaka will require hospital-level care for a maternal morbidity. Conclusions: In developing country urban settings with high public health care usage, meticulous review of hospital registers can provide baseline information on the burden of moderate-to-severe postpartum morbidity. © 2005 Vallely et al; licensee BioMed Central Ltd
Electrochemical properties and electrochemical impedance spectroscopy of polypyrrole-coated platinum electrodes
Polypyrrole (PPy) films of different thickness were characterized by electrochemical impedance spectroscopy (EIS) measurements in acetonitrile and aqueous solutions, containing 0.1 M NaClO4 or sodium dodecylsulfate as the dopant. The PPy films were electrochemically deposited on Pt, and their electrochemical properties studied by cyclic voltammetry. Impedance spectra were obtained at potentials ranging from 0 to 0.8 V/SCE. The EIS data were fitted using two different equivalent electrical circuits (depending on the nature of the dopant). They involve a diffusive capacitance, which increased with the passing charge during electrosynthesis (i.e. film thickness) for ClO4--doped PPy, but was practically unaffected by the film thickness in the case of SDS-doped PPy. Also, a double-layer capacitance was found only in the circuit of ClO4--doped PPy. It increased with the film thickness, and showed a minimum near the open-circuit potential. Finally the charge-transfer resistance (Rct) obtained with SDS is nearly 200-fold higher than that obtained with ClO4- in the same solvent (H2O). With the same dopant (ClO4-), Rct is about five times higher in acetonitrile relative to water. All these EIS results of the different types of PPy suggest a relation with the wettability of the polymer.KEY WORDS: Conducting polymers, Polypyrrole, Electrochemical impedance spectroscopy, Equivalent-electrical circuit, Micellar mediaBull. Chem. Soc. Ethiop. 2006, 20(2), 279-293
- …
