377 research outputs found
Estimating the burden of malaria in Senegal : Bayesian zero-inflated binomial geostatistical modeling of the MIS 2008 data
The Research Center for Human Development in Dakar (CRDH) with the technical assistance of ICF Macro and the National Malaria Control Programme (NMCP) conducted in 2008/2009 the Senegal Malaria Indicator Survey (SMIS), the first nationally representative household survey collecting parasitological data and malaria-related indicators. In this paper, we present spatially explicit parasitaemia risk estimates and number of infected children below 5 years. Geostatistical Zero-Inflated Binomial models (ZIB) were developed to take into account the large number of zero-prevalence survey locations (70%) in the data. Bayesian variable selection methods were incorporated within a geostatistical framework in order to choose the best set of environmental and climatic covariates associated with the parasitaemia risk. Model validation confirmed that the ZIB model had a better predictive ability than the standard Binomial analogue. Markov chain Monte Carlo (MCMC) methods were used for inference. Several insecticide treated nets (ITN) coverage indicators were calculated to assess the effectiveness of interventions. After adjusting for climatic and socio-economic factors, the presence of at least one ITN per every two household members and living in urban areas reduced the odds of parasitaemia by 86% and 81% respectively. Posterior estimates of the ORs related to the wealth index show a decreasing trend with the quintiles. Infection odds appear to be increasing with age. The population-adjusted prevalence ranges from 0.12% in Thille-Boubacar to 13.1% in Dabo. Tambacounda has the highest population-adjusted predicted prevalence (8.08%) whereas the region with the highest estimated number of infected children under the age of 5 years is Kolda (13940). The contemporary map and estimates of malaria burden identify the priority areas for future control interventions and provide baseline information for monitoring and evaluation. Zero-Inflated formulations are more appropriate in modeling sparse geostatistical survey data, expected to arise more frequently as malaria research is focused on eliminatio
Water stress induces overexpression of superoxide dismutases that contribute to the protection of cowpea plants against oxidative stress
Water stress is known to induce active oxygen species in plants. The accumulation of these harmful species must be prevented by plants as rapidly as possible to maintain growth and productivity. The aim of this study was to determine the effect of water stress on superoxide dismutase isozymes (SOD, EC 1.15.1.1.) in two cowpea cultivars [Vigna unguiculata L. Walp., cv. Bambey 21 (B21) and cv. TN88-63]. Plants were submitted to water stress by withholding water supply and the expression of SOD was characterized during stress induction. In the same time, photosynthesis characteristics were determinedthrough the measurement of the quantum yield of PS II photochemistry and the energy absorption rate per reaction centre. Results show how water stress regulates the synthesis and the activity of superoxide dismutase isoforms and how these enzymes contribute to protect photosynthesis against the damageable effects of superoxide radicals in cowpea. Increased MnSOD and FeSOD activity and concentration were shown to be induced by water stress and associated with protection of photosystem II photochemistry and whole plant growth against oxidative stress in these plants. On the contrary, plants unable to express high MnSOD and/or FeSOD isoforms showed more sensitivity to water stress
Crystal structure of methyl N-ferrocenylcarbamate
The asymmetric unit of the title compound, [Fe(C5H5)(C7H8NO2)], contains two independent molecules consisting of a ferrocenyl moiety and a nitrogen-bound methyl carbamate. These units are almost perpendicular to each other, making dihedral angles of 87.74 (9) and 87.32 (8)°. In each independent molecule, the cyclopentadienyl rings deviate slightly from an eclipsed conformation and lie virtually parallel [dihedral angles = 1.42 (15) and 0.49 (13)°]. In the crystal, molecules are linked by N—H...O hydrogen bonds into chains along the a-axis direction
The commodity systems of four indigenous leafy vegetables in Senegal
Increasing the production of traditional leafy vegetables that are well adapted to the agro-ecology of Senegal, easy to grow and requiring low inputs, could greatly help to solve the poverty and malnutrition problems in Senegal. However, leafy vegetables are often overlooked by the scientific community. The species of leafy vegetables dealt with in this paper are roselle (Hibiscus sabdariffa L.), cowpea (Vigna unguiculata (L.) Walp), amaranths (Amaranthus L. spp.) and Moringa (Moringa oleifera Lam). To increase production of traditional leafy vegetables, access to good quality seeds is necessary. Two plantcollecting missions were undertaken throughout Senegal by a multidisciplinary research team. Experimentation on Hibiscus regeneration and characterisation was conducted at ISRA-CDH research station. Sixty-four accessions were collected among the four species. Forty-eight accessions of roselle (Hibiscus sabdariffa L.) were characterised. The level of dissimilarity (63%) within the accessions of roselle confirmed the high degree of intra-species variability. The Richness Index determined for the Diaobe and Matam markets indicated a high degree of genetic diversity of roselle. These are used to select three new lines according to farmers’ preference criteria.In addition, socio-economic surveys were conducted in two pilot villages. It was found that planting dates for leafy vegetables varied greatly, depending on species, locality and season. Sowing was mainly done broadcast. Organic fertilisers were commonly applied. Eighty per cent (80%) of the farmers applied an NPK formulation and small quantities of urea. Traditional irrigation methods are often used in the growing of traditional leafy vegetables. The seeds used by farmers were a mixture of varieties. Farmers identified four types of each of roselle, amaranth and cowpea, but could not differentiate any variety for Moringa. Local markets constitute the main roselle seed supply source. Few farmers have developed traditional methods of seed conservation. Selling of seed is not a common activity in rural areas. Generally, farmers exchange gratuitously theirs seeds. Leaves are commonly sold at the field, in the village, in the nearest city and weekly at local markets called ’Louma‘. Average annual income generated by leaves varies from 41 to 500 USD. Leafy vegetables are used as food and for medicinal purposes. Leafy vegetable consumption in Senegal is around 23 g/person·d.Keywords: leafy vegetables, production, species, seed and genetic diversit
Pour une agriculture intelligente face au changement climatique au Sénégal: Recueil de bonnes pratiques d'adaptation et d'atténuation
Climate change is at the present time a new threat which leads to increased frequency and intensity of floods, droughts and cyclones with rising sea levels; thus placing additional demands on a situation already critical in rural areas.
In Senegal, as in many countries of the Sahel, those natural phenomena result in a significant drop in harvests, water shortages and worsening health crisis which leads to consequences such as growing food insecurity of the population; thus threatening the progress achieved in regards with the fight against poverty during the last century.
Indeed, many farmers live in rural areas which are characterized as low rainfall, saline soils, fragile or degraded soils and limited market access areas. The poverty in which they live, especially those of women, is often worsened by social exclusion. Such farmers are vulnerable because they depend directly on rainfall and seasons. They have little savings while supports from the government or their local authorities remain inadequate. It is essential to strengthen the adaptive capacity of vulnerable countries and communities to cope with the impacts of climate change on agriculture and food security.
This document is the result of a multi-criteria analysis of experiences of tackling climate variability, drought and desertification, and land degradation on one hand, and Adaptation to Climate Change in Senegal on the other.
It is carried out on the initiative of the national platform for science-policy dialogue on adaptation of agriculture and food security to climate change (C-CASA) for capacity building and informed decision making for adaptation to climate change.
This work has received technical and financial support from CCAFS Program (www.ccafs.cgiar.org).
It is intended for the use of field workers in the area of adaptation to climate change. It also serves as technologies and tools guide to adapt to climate change impacts in the area of agriculture and food security.
The manual is based primarily on (1) both the institutional and peasant experiences of the actors; (2) the recommendations of the reports of the Inter-governmental Panel on Climate Change (IPCC); (3) the procedures manual for assessing climate change impacts and adaptation strategies; (4) the results of development projects and applied research.
This is a collection that comes as a complement to other initiatives in the country and ongoing operations which provide practical examples of using the technological options for successful implementation of projects and programs and for the definition of agricultural policies in the Sahel
Effets de l’inoculation mycorhizienne sur le sesame (Sesamum indicum L.) en conditions naturelles
La présence des microorganismes symbiotiques dans le sol constitue un atout pour la majorité des cultures. L’inoculation avec des champignons mycorhiziens à arbuscules (CMA) est considérée comme un des moyens biologiques permettant à la culture de résister aux stress biotiques et abiotiques, et d’augmenter la productivité. Mais en conditions naturelles, la combinaison de plusieurs facteurs a une influence majeure dans l’établissement de la mycorhization. L’inoculation du sésame (Sesamum indicum L.) avec deux souches de Glomus est expérimentée en milieu naturel, dans un dispositif en split-plot avec quatre répétitions. Cetteinoculation mycorhizienne en milieu naturel a produit les effets suivants : le taux de mycorhization des plants inoculés reste bas ; l’inoculation n’a pas eu un effet significatif sur le rendement en graines, le nombre decapsules et la biomasse totale comparativement aux plants témoins naturellement infectés. Cela montre que, la mycorhization naturelle a eu une efficacité comparable à celle des souches inoculées sur le sesame. On peut déduire que les sols de cette zone de Bambey contiendraient des souches de champignons mycorhiziens à arbuscules (CMA) indigènes aussi efficaces que des souches sélectionnées.© 2013 International Formulae Group. All rights reserved.Mots clés : Mycorhization naturelle, Glomus mosseae, Glomus fasciculatum, sésame, productivité
Epidemiology of snakebites in Kedougou region (eastern Senegal) : comparison of various methods for assessment of incidence and mortality
Background: Although considered a public health issue in Senegal, the actual incidence and mortality from snakebite are not known. In the present study, an epidemiological survey was carried out in Kedougou region, southeastern Senegal, where envenomations, particularly by Echisocellatus, are frequent and severe. Methods: Three sources of data were used: records from health centers and reports by health professionals; traditional healers; and household surveys. Results: The annual incidence and mortality provided by health centers were 24.4 envenomations and 0.24 deaths per 100,000 population, respectively. The annual incidence recorded by traditional healers was 250 bites per 100,000 inhabitants, but the number of deaths was unknown. Finally, the household surveys reported an annual incidence of 92.8 bites per 100,000 inhabitants and an annual mortality rate of 2.2 deaths per 100,000 inhabitants. The differences in incidence and mortality between the different methods were explained by significant bias, resulting in particular from the complex patient's healthcare-seeking behavior. The incidence provided by health records should be used to specify the immediate quantitative requirements of antivenoms and places where they should be available first. Conclusion: Mandatory reporting of cases would improve the management of envenomation by simplifying epidemiological surveys. Patients' preference for traditional medicine should prompt health authorities to urge traditional healers to refer patients to health centers according to defined clinical criteria (mainly edema and bleeding or neurotoxic symptoms). Finally, household surveys were likely to reflect the actual epidemiological situation. Poison Control Center of Senegal should continue its work to sensitize stakeholders and train health staff
Segregation Distortions in an Interspecific Cotton Population issued from the [(Gossypium hirsutum x G. raimondii)² x G. sturtianum] Hybrid
The segregation ratio of 10 Gossypium sturtianum specific SSR markers belonging to linkage groups c2-c14, c3-c17, and c6-c25 was analysed in the BC2S6 progeny of the [G. hirsutum x G. raimondii)² x G. sturtianum] (HRS) hybrid; based on chi-square test. All the marker loci tested were associated with skewed allele frequencies (P<0.001) showing a strong SD with a zygotic selection. The possible causes and consequences of this massive segregation distortion are discussed
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