336 research outputs found

    Towards Understanding the Gene-Specific Roles of GATA Factors in Heart Development : Does GATA4 Lead the Way?

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    Funding: This work is supported by the British Heart Foundation (BHF): programme grant number: RG/18/8/33673 to Professor Stefan Hoppler. Acknowledgments: I would like to thank Stefan Hoppler for providing critical comments as well as valuable and constructive suggestions for the manuscript.Peer reviewedPublisher PD

    Genome-wide transcriptomics analysis identifies sox7 and sox18 as specifically regulated by gata4 in cardiomyogenesis

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    This work was supported by British Heart Foundation (BHF Project Grant no PG/13/23/30080 to B.A.A and S.H.), Biotechnology and Biological Sciences Research Council (BB/M001695/1 to S.H.) and the University of Aberdeen (for A.T.L). Acknowledgements We’re grateful to Ms Yvonne Turnbull and Ms Kate Watt for technical assistance and lab management. We would like to thank Professor Cedric Blanpain and Dr Xionghui Li from UniversitĂ© Libre de Bruxelles for providing training of ES cell manipulation and Mesp1/Gata4 cell lines. We are grateful to Professor Todd Evans from Weill Cornell Medical College for generously providing iGata ES cell lines. We also would like to thank Professor Aaron Zorn and Scott Rankin for providing Xsox18 plasmid.Peer reviewedPublisher PD

    Pathogenicity of indigenous entomopathogenic nematodes from Benin against mango fruit fly (Bactrocera dorsalis) under laboratory conditions

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    Bactrocera dorsalis fruit fly is the economically most significant tephritid pest species on Mango, Mangifera indica L., in Benin, and entomopathogenic nematodes (EPNs) represent good candidates for its control in the soil. In this study, the susceptibility of larvae and pupae of B. dorsalis to 12 EPN isolates originating from Benin was investigated. The effect of nematode concentrations (20, 50, 100, 200 and 300 Infective Juveniles (IJs)/B. dorsalis larva) and of different substrate moisture content (10, 15, 20, 25 and 30% v/w) on B. dorsalis mortality at the larval stage was studied. Also, the reproduction potential inside B. dorsalis larvae was assessed. Our results revealed that the susceptibility of B. dorsalis larvae was significantly different among the 12 tested nematode isolates with H. taysearae isolate Azohoue2 causing the greatest insect mortality (96.09 +/- 1.44%). The lowest insect mortality (7.03 +/- 4.43%) was recorded with Steinernema sp. strain Bembereke. Significant differences in insect mortality were recorded when EPNs were applied at varying IJs concentrations. A concentration of 100 nematodes of either H. taysearae Azohoue2 or H. taysearae Hessa1 per B. dorsalis larva was enough to kill at least 90% of B. dorsalis larvae. Larvae were less susceptible to nematodes at higher moisture content (25% and 30%). In addition, pupae were less susceptible to nematodes than larvae. Furthermore, the tested nematode isolates were able to reproduce inside B. dorsalis third instar larva with the Heterorhabditis isolates giving the greatest multiplication rate (59577.2 IJs +/- 14307.41)

    Analyse fréquentielle et nouvelle cartographie des maxima annuels de pluies journaliÚres au Bénin

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    Les pluies extrĂȘmes sont des phĂ©nomĂšnes rares qui sont la cause des inondations ayant des impacts sur la population. La prĂ©sente Ă©tude vise Ă  estimer et cartographier les maxima annuels des pluies journaliĂšres au BĂ©nin. A cet effet, les donnĂ©es de 35 stations ont Ă©tĂ© utilisĂ©es et couvrent globalement la pĂ©riode de 1921 Ă  2001. Cinq lois statistiques ont Ă©tĂ© utilisĂ©es pour l’analyse frĂ©quentielle. Le choix du meilleur modĂšle a Ă©tĂ© fait sur la base de la comparaison numĂ©rique. Les rĂ©sultats ont montrĂ© une prĂ©dominance des lois Gumbel et Lognormale. Dans l’ensemble, on note que les lois de probabilitĂ© des maxima annuels de pluies journaliĂšres, n’obĂ©issent pas spĂ©cifiquement Ă  un rĂ©gime pluviomĂ©trique donnĂ©. On constate Ă©galement que l’évolution des quantiles de pluie est proportionnelle Ă  celles des pĂ©riodes de retour car en effet, les pĂ©riodes de retour augmentent avec les quantiles de pluie. Les valeurs les plus Ă©levĂ©es sont gĂ©nĂ©ralement observĂ©es au niveau du Littoral, au Centre Est et au Nord Ouest du BĂ©nin. Ainsi, la prĂ©sente Ă©tude permet de disposer d’une nouvelle cartographie des maxima annuels des pluies journaliĂšres pour les pĂ©riodes de retour 5, 10, 50 et 100 ans au BĂ©nin.Mots clĂ©s : Pluies extrĂȘmes, analyse frĂ©quentielle, BĂ©nin

    Analyse De L’efficacitĂ© Allocative Et Economique Des SystĂšmes D’élevage Bovin Au Nord-Est Du BĂ©nin

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    Le niveau d’efficacitĂ© allocative et Ă©conomique des systĂšmes d’élevage bovin des communes de KalalĂ© et de Gogounou au Nord BĂ©nin a Ă©tĂ© Ă©valuĂ© dans ce travail. Reposant sur les donnĂ©es d’enquĂȘtes, il mesure les scores d’efficacitĂ© des systĂšmes d’élevage. Pour y parvenir, une typologie faisant ressortir trois modes de pratiques d’élevage bovin a Ă©tĂ© faite et vise une prĂ©sentation explicite des scores d’efficacitĂ© allocative et Ă©conomique des systĂšmes Ă©tudiĂ©s. Les diffĂ©rents intrants de l’élevage bovin sont utilisĂ©s dans un modĂšle translog stochastique et estimĂ© par le frontier 4.1. Il ressort de l’estimation que les systĂšmes d’élevage de la zone ont un score d’efficacitĂ© allocative de 42,79%. Ce score montre l’importance de l’allocation des ressources dans la production bovine des deux communes. L’efficacitĂ© Ă©conomique du systĂšme montre un score de 34,01%. Ce score montre la performance du systĂšme Ă  travers les techniques d’élevage et d’allocation des ressources. Les pratiques traditionnels, modernes, et commerciales d’élevage ont respectivement un score d’efficacitĂ© Ă©conomique moyen de 15,03% ; de 0,42% et de 7,49%. Les rĂ©sultats de l’étude mettent en Ă©vidence le faible niveau d’efficacitĂ© Ă©conomique des systĂšmes d’élevage. Tout cela montre l’intĂ©rĂȘt que reprĂ©senterait une politique de formation sur l’usage des facteurs de production en Ă©levage bovin. The level of allocative and economic efficiency of cattle farming systems in the communes of KalalĂ© and Gogounou in northern Benin was assessed in this work. Based on survey data, it measures the efficiency scores of farming systems. To achieve this, a typology highlighting three modes of cattle rearing practices was made and aims at an explicit presentation of the allocative and economic efficiency scores of the systemsstudied. The different inputs from cattle farming are used in a stochastic translog model estimated by the frontier 4.1. It is estimated that the farming systems in the area have an allocative efficiency score of 42.79%. This score shows the importance of resource allocation in beef production in the two municipalities. The economic efficiency of the system shows a score of 34.01%. This score shows the performance of the system through breeding techniques and resource allocation. Traditional, modern, and commercial animal husbandry practices have an average economic efficiency score of 15.03%, respectively; 0.42% and 7.49%. The results of the study highlight the low level of economic efficiency of farming systems. All this shows the value of a training policy on the use of production factors in beef farming

    Effets des DĂ©terminants du Prix International de RĂ©fĂ©rence du Coton en FCFA sur la CompĂ©titivitĂ© de l’Afrique de l’Ouest et du Centre

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    L’Afrique de l’ouest et du Centre (AOC) est le 3e exportateur de coton sur le marchĂ© mondial et y exporte la quasi-totalitĂ© de sa production. A cet effet, la maĂźtrise indispensable des dĂ©terminants du prix indiciel mondial qui sert de rĂ©fĂ©rence Ă  ses contrats de vente constitue l’objectif de cette Ă©tude axĂ©e sur la compĂ©titivitĂ© et dans laquelle sont expliquĂ©s la Part de marchĂ© et le Profit de l’AOC grĂące aux modĂšles Auto Regressive Distributed Lag (ARDL) et Probit. Sur la part de marchĂ©, les tests rĂ©vĂšlent Ă  court terme des effets positifs du taux de change dollar-FCFA, de la production de l’AOC, de la consommation et du stock du monde ; et des effets nĂ©gatifs de la volatilitĂ© et de l’élasticitĂ©-prix de l’indice A en FCFA, de la dĂ©valuation de 1994, du stock de l’AOC et de la production mondiale. A long terme, on observe des effets positifs du taux de change dollar-FCFA, de la production de l’AOC, des pandĂ©mies ; et des effets nĂ©gatifs du stock de l’AOC. Sur le Profit, on observe des effets positifs de la production de l’AOC. Ainsi pour croitre sa compĂ©titivitĂ©, l’AOC doit amĂ©liorer son systĂšme de production et crĂ©er sa propre place de marchĂ© pour mieux maĂźtriser les prix et valoriser ses avantages comparatifs.   West and Central Africa (WCA) is the 3rd cotton exporter on the world market and exports almost all of its production there. To this end, the essential mastery of the determinants of the world index price which serves as a reference for its sales contracts constitutes the objective of this study focused on competitiveness and in which the Market Share and Profit of the AOC are explained thanks to Auto Regressive Distributed Lag (ARDL) and Probit models. On the market share, the tests reveal in the short-term positive effects of the dollar-FCFA exchange rate, of the production of the AOC, of ​​the consumption and of the world stock; and the negative effects of the volatility and price elasticity of the A index in FCFA, the 1994 devaluation, the AOC stock and world production. In the long term, there are positive effects of the dollar-FCFA exchange rate, AOC production, pandemics; and negative effects of the AOC stock. On the Profit, we observe positive effects of the production of the AOC. Thus, to increase its competitiveness, the AOC must improve its production system and create its own market place to better control prices and enhance its comparative advantages

    Effets des DĂ©terminants du Prix International de RĂ©fĂ©rence du Coton en FCFA sur la CompĂ©titivitĂ© de l’Afrique de l’Ouest et du Centre

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    L’objet de ce chapitre est d’analyser les effets des dĂ©terminants de l’indice A en FCFA sur la compĂ©titivitĂ© de l’AOC Ă©valuĂ©e Ă  travers la part de marchĂ© et le profit. AprĂšs la dĂ©tection de relations de cointĂ©gration par le test de cointĂ©gration aux bornes, l’estimation du modĂšle Ă  correction d’erreur ARDL-ECR est validĂ© par une force de rappel de -0.990695, un R2 de 86,84%, des tests de diagnostic de rĂ©sidus rĂ©ussis et le test de stabilitĂ© du modĂšle. Sur la part de marchĂ© et de façon significative, la dynamique de l’indice A Cotlook en FCFA se manifeste Ă  court terme par des effets positifs du taux de change dollar-FCFA et des effets nĂ©gatifs de la volatilitĂ© et de l’élasticitĂ©-prix de l’indice A en FCFA, de la rupture (dĂ©valuation) survenue en 1994. A long terme et toujours de façon significative, elle se manifeste par des effets positifs du taux de change dollar-FCFA. Les dĂ©terminants de l’indice eux se manifestent Ă  court terme par des effets positifs de la production de l’AOC, de la consommation et du stock du monde ; et des effets nĂ©gatifs du stock de l’AOC et de la production mondiale. A long terme, ces dĂ©terminants se manifestent par des effets positifs de la production de l’AOC, des pandĂ©mies ; et des effets nĂ©gatifs du stock de l’AOC. Sur le Profit, le modĂšle Probit validĂ© par les tests de diagnostics des rĂ©sidus rĂ©vĂšle uniquement des effets significatifs et positif de la production de l’AOC. Face aux effets nĂ©gatifs de la volatilitĂ© et de la dĂ©valuation, l’AOC se trouve dĂ©munie et ne peut rĂ©agir. Par contre, les effets de sa production sont bĂ©nĂ©fices sur la part de marchĂ© et le profit et ouvrent des champs possibles d’amĂ©lioration de sa compĂ©titivitĂ©. Il s’agit (1) de la crĂ©ation d’une place de marchĂ© propre avec des institutions permettant de moins s’exposer aux impacts nĂ©gatifs de la dynamique des cours internationaux et de mieux valoriser ses avantages comparatifs ; (2) de l’amĂ©lioration continue de la performance opĂ©rationnelle des systĂšmes de production aussi bien agricoles qu’industriels ; et (3) de la meilleure valorisation de la qualitĂ© de la fibre par le passage du classement manuel en Ɠuvre Ă  l’AOC au classement instrumental utilisĂ© par le reste du monde.   The purpose of this chapter is to analyse the effects of the dynamics and determinants of the index A in FCFA on the competitiveness of the AOC evaluated through market share and profit. After the detection of cointegration relations by the cointegration test at the terminals, the estimation of the error-corrected model ARDL-ECR is validated by a recall force of -0.990695, an R2 of 86,84%, successful residue diagnostic tests and model stability test. In terms of market share and significantly, the dynamics of the A Cotlook index in FCFA are reflected in the short term by positive effects of the dollar-FCFA exchange rate and the negative effects of the volatility and price elasticity of the A index in FCFA, the break-up (devaluation) in 1994. In the long term, and still significantly, it is reflected in the positive effects of the dollar-FCFA exchange rate. The determinants of the index are manifested in the short term by positive effects of the production of the AOC, the consumption and the world stock; and the negative effects of the AOC stock and world production. In the long term, these determinants manifest themselves in positive effects of the production of AOC, pandemics; and negative effects of the AOC stock. On Profit, the Probit model validated by the residue diagnostic tests only reveals significant and positive effects of AOC production. Our hypothesis is thus confirmed. Faced with the negative effects of volatility and devaluation, the AOC finds itself deprived and unable to react. On the other hand, On the other hand, the effects of its production are beneficial on market share and profit and open up possible fields for improving its competitiveness.. It concerns (1) the creation of a market place with its own institutions allowing less exposure to the negative impacts of the dynamics of international prices and to better value its comparative advantages; (2) continuous improvement in the operational performance of both agricultural and industrial production systems; and (3) the best enhancement of the quality of the fiber by the transition from the manual classification in use to the AOC to the instrumental classification used by the rest of the world
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