709 research outputs found

    Mitigation and Adaptation Strategies – Organic Agriculture

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    This psoter presents information on the following - The concept of organic farming in the context of climate change - Carbon sequestration on organic farms - Consequences of an area-wide conversion to organic agricultur

    Avantages des biodigesteurs sur le bois de chauffe dans les élevages laitiers à Kaolack (Sénégal)

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    Le dĂ©ficit Ă©nergĂ©tique constitue une contrainte Ă  l’épanouissement des mĂ©nages ruraux notamment, au niveau de l’énergie de cuisson. Les femmes utilisent le bois de chauffe pour les besoins Ă©nergĂ©tiques de la cuisson mais aussi, pour la pasteurisation du lait. Cette Ă©tude met en Ă©vidence les avantages de l’utilisation des biodigesteurs sur le bois de chauffe dans les Ă©levages laitiers Ă  Kaolack (SĂ©nĂ©gal). Cent seize mĂ©nages ont Ă©tĂ© enquĂȘtĂ©s dont 58 dĂ©tenteurs de biodigesteurs. Les rĂ©sultats montrent que les mĂ©nages possĂ©dant un biodigesteur avaient plus de temps pour se consacrer Ă  des activitĂ©s rĂ©munĂ©ratrices ou pour le bien ĂȘtre de la famille avec un tiers (32,75 %) qui mettent moins de 2 h par jour pour la recherche du bois et 2 h pour la cuisson d’un repas contre (67,25 %) de mĂ©nages sans biodigesteurs qui y consacraient 2 Ă  6 h par jour et plus de 3 h pour la cuisson d’un repas. Plus du quart (25,86 %) des mĂ©nages avec biodigesteurs utilisaient le biogaz comme source d’éclairage. De mĂȘme, 36,20 % prĂ©parent les repas et pasteurisent le lait avec le biogaz. Il est Ă©galement constatĂ© une rĂ©duction de la frĂ©quence des pathologies respiratoires et oculaires mais aussi des dĂ©penses pour l’achat de combustible et de compost.Mots clĂ©s: Biogaz ; bois ; Ă©levages laitiers ; Ă©conomie des mĂ©nages ; Kaolack ; SĂ©nĂ©gal Biodigester benefits on wood heating in dairy farming of Kaolack (Senegal)The energy deficit is a major constraint to the development of rural house holds including at cooking energy. Women use firewood for cooking energy needs but also for the pasteurization of milk. This study highlights the benefits of using biogas digesters on firewood in dairy farms in Kaolack (Senegal). One Hundred sixteen households were surveyed of which 58 possessed biodigester.The results show that households with a biodigester had much more time devoted to income-generating activities or for the welfare of the family. One third (32.75 %) of biodigester owners take less than 2 hours per day for wood search and 2 hours for cooking a meal against (67.25 %) of house holds without biodigester who spent 2 to 6 hours per day and put more than 3 hours to cook meal. More than a quarter (25.86 %) of households with biodigester used biogas as a lighting. Similarly, 36.20 % Cook food and pasteurize milk with biogas.The used of biogas expenses for the purchase of fuel as well as the compost for filed fertilization. It seem that biogas utilization reduce the incidence of respiratory and eye diseases.Keywords: Biogas ; wood ; dairy farms ; household economy ; Kaolack ; Senegal

    The Informal Sector In Francophone Africa: Firm Size, Productivity, And Institutions

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    This book is a major step towards improving the understanding of the complex reality of informal sector firms in francophone West Africa. It innovates by concentrating on informal firms rather than informal employment (as other studies do), and identifying \u27large informal\u27 sector firms whose sales rival those of large formal-sector firms but operate in ways that are similar to small informal operators. Not only is the regulatory environment facing these two types of informal firms distinct, but policies aimed at improving their productivity need to be differentiated. This study focuses on the urban informal sector in three capital cities: Dakar (Senegal), Cotonou (Benin), and Ouagadougou (Burkina Faso). The study also breaks new ground with an eclectic methodology and primary data collection. Quantitative and qualitative firm-level data were collected involving a unique and fruitful collaboration among academic researchers, government officials, the West African economic and monetary union commission, informal and formal sector business associations, and labor unions. This volume represents the culmination of a long collaboration between the Centre de Recherches Economiques Appliquees (CREA) at the University Cheikh Anta Diop of Dakar and the World Bank

    Social Capital and Citizens’ Attitudes towards Migrant Workers

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    This study examines Qatari citizens’ attitudes toward migrant workers. While much research has been conducted on citizens’ attitudes toward the abolition, tightening, or loosening of the Kafāla system in the Gulf Cooperation Council (GCC) countries with regard to migrant workers’ residency rights, and on their contribution to the economic development of these countries, little is known about how citizens’ religiosity and social engagement impact their acceptance of migrant workers. In the present study, we address this question by examining the effects of religious and social capital on Qatari citizens’ preferences for having Arab and Western migrant workers as neighbours, drawing on data from two nationally representative surveys in Qatar. The results indicate that, even after controlling for a wide range of socio-demographic attributes, social capital in terms of trust and bridging social ties has a strong effect on the Qatari nationals’ preferences

    Caractérisation agropédologique des sols de mboltime dans la zone des niayes (Sénégal)

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    L'objectif de cette étude était de faire une évaluation de la fertilité physico-chimique de différents sols du village de Mboltime et de déterminer les similarités relatives. Les horizons de cinq fosses pédologiques (P1 , P2, P3, P4 et P5) ouvertes dans les zones dunaires et inter-dunaires ont servi à cet effet. Les résultats obtenus ont montré que les horizons de surface sont sableux à sablo-limoneux avec des pH et conductivité électrique variant selon les profils et les horizons. Seul le profil P4 a montré des sols acides et salés au niveau des horizons P4H1, P4H3 et P4H5. Les autres profils ont montré des sols neutres à légÚrement alcalins et non salins. Les teneurs en matiÚre organique et azote total ont été assez faibles dans les profils 1, 2, 3 et 5, et moyens dans le profil 4 avec un rapport C/N variant de 2,72 à 16,50. Les teneurs en Ca2+, Mg2+, Na+ et K+ varient suivant le C et N. Le cation le plus abondant dans les sols a été le Ca2+; suivi du Mg2+ et du Na+ alors que K+ a été le cation le moins abondant. L'analyse factorielle des correspondances (AFC) a permis de mettre en évidence deux groupes de sols en fonction de la salinité et de l'acidité. Un groupe I constitué de sols trÚs salins et un groupe II constitué de sols non salins. Cette étude a mis en évidence deux contraintes majeures à la production végétale dans le village de Mboltime que sont la salinité et l'acidité des sols.Mots clés : Sol, Profil pédologique, Niayes, salinite ; Sénégal AGROPEDOLOGICAL CARACTERIZATION OF MBOLTIME SOILS IN NIAYES AREA (SENEGAL)The objective of this study was to evaluate physico - chemical properties of different soils from Mboltime village and relevant similarities. Horizons of five soil profiles (P1, P2, P3, P4 and P5) in the dune and inter-dune areaswere used for that purpose. The results showed variance in topsoil contents of sand with silt- loam, pH and electric conductivity according to the  profiles. Only the P4 profile presents acid and salty soil to the level asof horizons P4H1, P4H3 and P4H5. The other profiles presented neutral to slightly alkaline soil pH with limited salinity. The soil contents of organic matter, and total nitrogen were rather weak in the profiles 1, 2, 3 and 5, and moderate in profile 4. The C/N ratio values varied from 2.72 to 16.50 while soil contents of Ca2+, Mg2+, Na+ and K+ variations were according to C and N. The most abundant cations in land was Ca2+; followed by Mg2+, Na+ and K+ was the least abundant cationin soils. The factorial  correspondence analysis (FCA) showed two groups of soil according to  salinity and acidity mainly depending to high and low salinity respectively. This study showed two major constraints to land productivity in the village of Mboltime which are the salinity and the acidity of soils.Keywords : Soil, soil profile, salinity, Niayes, Senega

    Indirect inguinal hernia masquerading as a Spigelian hernia

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    Inguinal hernia usually developed and descended into scrotum. The clinical presentation is inguinal or inguino-scrotal swelling. Abdominal wall weakness as it is frequently seen in African tropical zones produces often rare clinical case. We report a case of inguinal hernia presented as an abdominal wall swelling clinically suggestive of a Spigelian hernia and discuss the mechanism

    Incidence et regulation naturelle de la chenille mineuse de l’epi de mil, Heliocheilus albipunctella de joannis (Lepidoptera, Noctuidae) a bambey dans le bassin arachidier au Senegal

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    Au SĂ©nĂ©gal, la mineuse de l’épi, Heliocheilus albipunctella (Lepidoptera, Noctuidae) a commencĂ© Ă  causer des dĂ©gĂąts dans les cultures de mil suite Ă  une longue pĂ©riode de sĂ©cheresse au dĂ©but des annĂ©es 70. Le suivi d’un rĂ©seau de 45 parcelles de producteurs Ă  Bambey en 2013, a permis d’évaluer la situation du ravageur : abondance relative (oeuf et larve), parasitisme associĂ©, potentiel de rĂ©gulation naturelle et pertes de rendement liĂ©es aux dĂ©gĂąts. Les rĂ©sultats ont montrĂ© une distribution trĂšs hĂ©tĂ©rogĂšne du ravageur dans la zone avec des moyennes d’infestation des Ă©pis en oeufs de 40 % et en larves 76 %. Un taux moyen de parasitisme des oeufs par TrichogrammatoĂŻdea sp estimĂ© Ă  2 % est notĂ© (n = 2281 oeufs). Le parasitisme larvaire est dominĂ© par des cocons d’endoparasitoĂŻdes de la famille des Ichneumonidae (8,6 %), des larves de Tachinidae (5,2 %) et des morphotypes non encore identifiĂ©s (4,6 %). Une faible mortalitĂ© larvaire due au Bracon sp. (1,5 %, n = 1567 larves) est observĂ©e. Ce faible taux de parasitisme, comparĂ© au potentiel rĂ©el de la rĂ©gulation naturelle observĂ©e (59 %, n = 45 parcelles) montre l’importance probable des ennemis naturels dans le contrĂŽle du ravageur. Les pertes en grains sont estimĂ©es Ă  10 %.Mots clĂ©s : Heliocheilus albipunctella, mil, rĂ©gulation Ă©cologique, ennemis naturels, dĂ©gĂąt

    An intuitionistic approach to scoring DNA sequences against transcription factor binding site motifs

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    Background: Transcription factors (TFs) control transcription by binding to specific regions of DNA called transcription factor binding sites (TFBSs). The identification of TFBSs is a crucial problem in computational biology and includes the subtask of predicting the location of known TFBS motifs in a given DNA sequence. It has previously been shown that, when scoring matches to known TFBS motifs, interdependencies between positions within a motif should be taken into account. However, this remains a challenging task owing to the fact that sequences similar to those of known TFBSs can occur by chance with a relatively high frequency. Here we present a new method for matching sequences to TFBS motifs based on intuitionistic fuzzy sets (IFS) theory, an approach that has been shown to be particularly appropriate for tackling problems that embody a high degree of uncertainty. Results: We propose SCintuit, a new scoring method for measuring sequence-motif affinity based on IFS theory. Unlike existing methods that consider dependencies between positions, SCintuit is designed to prevent overestimation of less conserved positions of TFBSs. For a given pair of bases, SCintuit is computed not only as a function of their combined probability of occurrence, but also taking into account the individual importance of each single base at its corresponding position. We used SCintuit to identify known TFBSs in DNA sequences. Our method provides excellent results when dealing with both synthetic and real data, outperforming the sensitivity and the specificity of two existing methods in all the experiments we performed. Conclusions: The results show that SCintuit improves the prediction quality for TFs of the existing approaches without compromising sensitivity. In addition, we show how SCintuit can be successfully applied to real research problems. In this study the reliability of the IFS theory for motif discovery tasks is proven

    Existence and asymptotic behavior of solutions for neutral stochastic partial integrodifferential equations with infinite delays

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    In this work we study the existence, uniqueness and asymptotic behavior of mild solutions for neutral stochastic partial integrodifferential equations with infinite delays. To prove the results, we use the theory of resolvent operators as developed by R. Grimmer [12] R. Grimmer. Resolvent operators for integral equations in a banach space. Transactions of the American Mathematical Society, 273(1): 333-349, 1982, as well as a version of the fixed point principle. We establish sufficient conditions ensuring that the mild solutions are exponentially stable in pth-moment. An example is provided to illustrate the abstract results.Fondo Europeo de Desarrollo RegionalMinisterio de EconomĂ­a y CompetitividadConsejerĂ­a de InnovaciĂłn, Ciencia y Empresa (Junta de AndalucĂ­a
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