256 research outputs found

    Impacts des activités socio-économiques sur les ressources en eau du barrage de Tera au Niger

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    Situé dans le Liptako nigérien, en zone de socle, où les ressources en eau souterraines sont limitées, le département de Téra et, en particulier, son chef lieu, la ville de Téra, est confrontée à un problème aigu d’approvisionnement en eau potable des populations. Aussi, comme solution à ce manque d’eau qui bloque toutes les activités socioéconomiques de la ville, on a réalisé en 1978 le barrage de Téra, dans le cadre de la coopération Nigéro-chinoise. Cependant, la réalisation du réseau d’adduction en eau potable (AEP), a accusé un grand retard dans sa mise en oeuvre. Aussi, les Hautes Autorités du Niger, ont autorisé en 1985, l’utilisation de l’eau du barrage pour l’irrigation, les besoins domestiques, la pêche, etc. L’analyse de ces différentes activités socioéconomiques, développées autour du barrage, montre que celles-ci ont eu des impacts négatifs aussi bien sur la quantité que sur la qualité des eaux du barrage, dont entre autres, les phénomènes d’ensablement/envasement et de pollution.Par ailleurs, cette étude montre que les différents usages de l’eau du barrage sont des sources de revenus substantiels pour plusieurs ménages, leur permettant de lutter contre l’insécurité alimentaire et la pauvreté. Aussi, compte tenu des menaces graves qui posent sur les ressources en eau du barrage, jouant désormais un rôle socioéconomique pour la population de Téra, voire de la Commune de Téra, il paraît urgent d’entreprendre des actions pour une gestion rationnelle et durable des ressources en eau du barrage de Téra, c'est-à-dire, promouvoir au niveau du barrage, la Gestion Intégrée des Ressources en Eau (GIRE), approche adoptée par l’Etat nigérien pour la gestion des ressources hydriques du pays.Mots-clés : Liptako nigérien, AEP, usages des eaux barrage, pollution GIRE, AEP, Téra

    Application of fast technology for analysis (FTA) for sampling and recovery of deoxyribonucleic acid (DNA) for molecular characterization of cowpea breeding lines for Striga resistance

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    Article purchasedStriga gesnerioides (Willd) Vatke is a significant constraint to cowpea production in the dry savannas of sub-Saharan Africa. Yield losses caused by S. gesnerioides in these regions are estimated in millions of tons annually and the prevalence of Striga soil infestation is steadily increasing. Conventional breeding efforts have developed some cowpea lines with Striga resistance as well as other important agronomic traits but it is time-consuming and difficult to pyramid favorable traits. The use of marker-assisted selection (MAS) makes it easier to select plant traits and reduce the time needed to develop new varieties. The potential of Fast Technology for Analysis (FTA) as an effective technology for sampling and retrieval of DNA from plant tissue and their subsequent molecular analysis was assessed in the laboratory. DNA was successfully recovered from the leaf tissues of cowpea pressed into the FTA® Classic card and the DNA obtained from the FTA papers was found to be suitable for molecular analysis by PCR-based techniques. The marker efficiency of Sequence Characterized Amplified Region (SCAR) marker MahSe2 and C42B was 93% in detecting SG3 resistance. This study demonstrated that the application of MAS using FTA technology has the potential to put the breeding process on a fast track and increase the efficiency of breeding activities

    Communicating seasonal forecasts to farmers in Kaffrine, Senegal for better agricultural management

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    Our project explaining seasonal forecasting to farmers in central Senegal built common ground between scientific forecasting and traditional knowledge. It helped farmers understand and use seasonal forecasts to improve crop strategies, and let farmers explain to meteorologists what seasonal climate information they most needed, in turn improving the forecasts’ usefulness

    Experimental study in natural convection

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    The study of thermal and ventilation parameters, obtained in a transient, laminar solar chimney of reduced dimensions, (1 < m <3) m with a square collector (side = 2m) is presented. Experimental measurements has been made to determine the temperature of the absorber and the fluid in the collector, it is shown that at the entrance of the chimney, the temperature of the absorber decreases slightly while that of the fluid is maintained at a maximum level. Temperature differences were observed up to 32°C between the atmosphere and the fluid in April. A temperature variation at the absorber depending on the stack height is presented. Temperature measurements in the chimney, at various heights depending on the axial coordinate, show a variable temperature profile. It is, from these, shown that, in the selected interval of stack height, the average speeds of output increase linearly as a function of stack height. For a chimney of 3m in height and 20cm in diameter, a maximum speed of approximately 0.7 ms-1 was observed. The lack of appropriate equipment handicaps the velocity measurement at the chimney entrance. Thus, the results of simulations with the computer code COMSOL 5.1 has confirmed temperature values measured at the chimney entrance and after this, velocity values are determined.KEYWORDS: 1- Solar chimney, 2- Laminar convection, 3- Temperature, 4- Outlet velocit

    Options de Modèles d’Affaires pour Assurer la Durabilité de l’Utilisation des Services d’Information Climatique au Sénégal

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    USAID/CINSERE (Services d’information climatiques pour améliorer la résilience et la productivité au Sénégal) est un projet de résilience qui vise à renforcer les capacités nationales pour la production, l’accès et la diffusion efficiente d’informations météorologiques et climatiques (IC) et de développer des stratégies pour une mise à l’échelle durable de l’utilisation des services d’information météorologiques et climatiques (SIC) sur toute l’étendue du territoire national. Le projet est financé par l’USAID et mis en œuvre par le Programme de Recherche du CGIAR sur le Changement Climatique, l’Agriculture et la Sécurité Alimentaire hébergé par ICRISAT (CCAFS/ICRISAT) en collaboration avec l’ANACIM. La zone d’intervention du projet est celle des projets Feed the Future (FtF) au Sénégal, notamment Naatal Mbay (clôturé en 2019), Yaajeende (remplacé par Kawolor en 2018), ERA (remplacé par Youth in Agriculture en 2018) et COMFISH (remplacé par Dekkal Geej en 2019). Démarré en Mai 2016 pour une durée de trois ans (Jusqu’en mai 2019), le projet a bénéficié d’une extension d’un an. Ainsi, cette première phase de l’USAID/CINSERE prend fin en avril 2020. Durant presque quatre années de mise en œuvre, des résultats assez probants ont été atteints tant dans la production des SIC, la communication et l’utilisation de ces SIC, que dans le renforcement des capacités des bénéficiaires à utiliser de façon efficiente ces SIC. Dans le souci de préserver les acquis du projet et d’assurer une mise à l’échelle soutenue du système de développement et de fourniture des IC en vue d’une utilisation durable des IC au Sénégal, l’USAID a recommandé l’identification, le test, la validation et la mise en œuvre de modèles économiques viables impliquant des partenaires aussi bien du public que du privé (PPP). Le projet USAID/CINSERE s’est donc inspiré des expériences et leçons apprises au Sénégal, au Ghana, au Mali, en Inde et en Amérique Latine (Colombie) en matière de modèles économiques dans la fourniture des SIC pour bâtir des modèles adaptés au contexte du Sénégal. Ce document présente les modèles identifiés ainsi que les défis et perspectives

    Implementation of active management of the third period of childbirth for the prevention of immediate post-partum bleeding in four regional maternity hospitals of Conakry, Guinea

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    Background: The objective of this study was to determine the frequency, skills level of health care service providers; to identify complications and difficulties related to the implementation of AMTPC/GATPA.Methods: It was about prospective study, descriptive of 6 months (1st March to 31st August 2014) carried out in the maternity hospitals of Faranah, Kindia, Mamou and Nzérékoré. It concerned the parturient women who had recently given birth and the personnel that carried out AMTPC/GATPA in these hospitals.Results: During the study period of 1,254 out of 1,305 births had benefited of AMTPC/GATPA, a frequency of 96.1%. The midwives were the most represented personnel in the implementation of GATPA (44.1%). In 46.4% of the cases, the health care service providers acquired this competence from the initial training. The release was obtained in the first trial in 64.9% cases. The duration of implementation of GATPA was less than 5 minutes in 72.6% cases. The different stages were respected in 91.5% cases. Complications were dominated by retention of placental fragments (10.2%). Lack of oxytocin was the main difficulty (36.6%).Conclusions: The sustainability of this achievement would depend on the systematic and correct implementation of AMTPC/GATPA at all childbirth attendants and the effective management of oxytocin

    Emploi des jeunes au Mali : caractéristiques et défis

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    The encouraging macroeconomic performance recorded by Mali over the past ten years has failed to create the conditions for sustained social and economic development for all segments of the population. Many initiatives put in place by the public authorities through job creation schemes have also been unable to cope with the growing unemployment, particularly among the young population. Access to employment and income is today a major challenge for the working population in this country, especially young people. The methodology relates to the documentary review, the collection of data at the level of the productive structures of statistical information of the Malian public administrations following the analysis of these data. It will attempt to highlight the many challenges facing the country. Since the challenges to be met are immense, they will have to be made priorities in order to encourage an increase in the population actively participating in the production of goods and services. Since beyond the economic situation, the degree of development, even of well-being, may, in some respects, be linked to unemployment rates. The characterization of youth employment in this work has made it possible to make implications in terms of economic policies. All things that would improve the employability of young people and avoid crises and conflicts related to youth unemployment.   Classification JEL : J64 Paper type: Empirical ResearchLes performances macroĂ©conomiques encourageantes qu’a enregistrĂ©es le Mali au cours des dix dernières annĂ©es n’ont pas rĂ©ussi Ă  crĂ©er les conditions de dĂ©veloppement social et Ă©conomique soutenu pour toutes les couches de la population.  Nombreuses initiatives mises en place par les pouvoirs publics Ă  travers des dispositifs de crĂ©ation d’emplois n’ont pas pu Ă©galement faire face Ă  au chĂ´mage de plus en plus croissant notamment au sein de la population jeune. L'accès Ă  l'emploi et au revenu constitue aujourd’hui dans ce pays un dĂ©fi majeur pour la population active, en particulier les jeunes. La mĂ©thodologie porte sur la revue documentaire, la collecte des donnĂ©es au niveau des structures productrices d’informations statistiques des administrations publiques du Mali suivies de l’analyse des donnĂ©es. Elle tentera de mettre en exergue les nombreux dĂ©fis auxquels le pays fait face. Les dĂ©fis Ă  relever Ă©tant immenses, il va falloir en faire des prioritĂ©s afin de favoriser un accroissement de la population participant activement Ă  la production des biens et services. Puisqu’au-delĂ  de la situation Ă©conomique, le degrĂ© de dĂ©veloppement, voire du bien-ĂŞtre, peut-ĂŞtre, Ă  des Ă©gards, liĂ©s aux taux de chĂ´mage. La caractĂ©risation de l’emploi des jeunes dans ce travail a permis de faire des implications en termes de politiques Ă©conomiques. Toutes choses qui permettraient d’amĂ©liorer l’employabilitĂ© des jeunes et d’éviter des crises et conflits liĂ©s au chĂ´mage des jeunes.   Classification JEL: J64 Type de papier : Recherche empirique &nbsp

    Optical and Thermal Performance Analysis of a Steady Spherical Collector with a Crescent-shaped Rotating Absorber

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    In this paper, optical analysis of spherical concentrator is made to determine the local and the global geometric concentration, as knowing the geometric concentration of a system can help predict what temperatures can possibly be obtained with it.This leads to conclude that spherical collectors may produce higher temperatures than parabolic trough, and they could even be sharply improved by using a mixt cylindrical and cavity (or flat) absorber. A craft prototype of a steady spherical concentrator made with concreteand having a smooth inner surface mapped with mirror tape is presented. Its absorber is made with blacken steel sheets and shaped like a moon crescent to be aligned with the declination plan and to avoid motorization for the tracking of the sun from East to West. Experimental measurements lead to temperatures reaching 686°C on the curve of the least diffusion, and 252°C in the absorber oven-like reservoir. Overall, the resultsuggests higher potentialities of spherical collectors,which also show possibility of use with much reduced tracking system and less vulnerability to bad weather

    Characterizing and forecasting climate indices using time series models.

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    The objective of the current study is to present a comparison of techniques for the forecasting of low frequency climate oscillation indices with a focus on the Great Lakes system. A number of time series models have been tested including the traditional Autoregressive Moving Average (ARMA) model, Dynamic Linear model (DLM), Generalized Autoregressive Conditional Heteroskedasticity (GARCH) model, as well as the nonstationary oscillation resampling (NSOR) technique. These models were used to forecast the monthly El Niño-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) indices which show the most significant teleconnection with the net basin supply (NBS) of the Great Lakes system from a preliminary study. The overall objective is to predict future water levels, ice extent, and temperature, for planning and decision making purposes. The results showed that the DLM and GARCH models are superior for forecasting the monthly ENSO index, while the forecasted values from the traditional ARMA model presented a good agreement with the observed values within a short lead time ahead for the monthly PDO index

    Surgical intervention on uterine fibromyoma in a country with limited resources: case of the gynaecology-obstetrics department of the Communal Medical Centre of Ratoma Conakry - Guinea

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    Background: In developing countries, treatment of uterine fibromyoma is confronted with numerous problems, namely: financial inaccessibility to the proposed treatments, fear of surgery and the weakness of the technical platform. The objectives of the study were to calculate the frequency of uterine fibromyomas, describe the socio-demographic characteristics of patients, identify the main clinical data and to describe the modalities of surgical management.Methods: It was a mixed descriptive study, cumulative over a period of 5 years (60 months) with data collection in two phases: a 4-year retrospective study from January 1, 2015 to December 31, 2018 and a 1-year prospective study from January 1, 2019 to December 31, 2019.Results: Authors collected 135 cases of uterine fibromyomas operated on out of a total of 260 cases of gynaecological pathologies, i.e. a frequency of 51.92%. Nulliparous women were the most concerned (45.18%), and women who attended school (60%) and those who did not attend school (40%). Women at home and housewives accounted for 42.20% and 54.07% respectively. Clinically, the circumstances of discovery were dominated by menometrorrhagia and menorrhagia respectively 77.77% and 68.14%. The large uterus was the most frequent physical sign found in 96.29% of cases. Uterine fibromyomas were recorded in 86.6% of cases in women with genital activity. The operative indications were dominated by the large polymyomatous uterus (64.44%), followed by hemorrhagic fibroma (18.52%) The surgical treatment was conservative in 92.60%. The total hysterectomy was performed in 7.40. Lethality was 1.4%.Conclusions: The surgical management of fibroids contrasts conservative treatment (myomectomy) with radical treatment (hysterectomy) with multiple possible approaches (hysteroscopy, vaginal surgery, laparoscopy or laparotomy). In this context, only laparotomy was possible due to lack of equipment. Laparoscopy and hysteroscopy equipment are necessary for less invasive surgery
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