Efficacité et productivité des banques de la zone UEMOA dans un contexte de réformes financières. Une application de la méthode DEA (Banks efficiency and productivity in the WAEMU in a context of financial reforms : an application of the DEA method)

L’objectif de cette étude est d’une part de mesurer les effets des réformes financières sur l’efficacité et la productivité des banques de la zone UEMOA sur la période de 1996 à 2006 et, d’autre part, de faire ressortir les principaux déterminants managériaux de l’efficacité de ces banques. L’estimation des scores de productivité et d’efficacité est effectuée au moyen de l’analyse de l’enveloppement des données (DEA). Les résultats montrent premièrement que les inefficiences techniques pures dominent les inefficiences d’échelle au niveau de tous les pays la zone excepté le Sénégal. Ainsi, l’inefficience relève plus d’une sous-utilisation des inputs que de rendements d’échelle inappropriés. Deuxièmement, la productivité globale des facteurs a connu une amélioration due essentiellement à la variation positive des progrès technologiques au détriment de l’efficacité technique sur toute la période de l’étude. Ceci laisse penser que les réformes financières n’ont pas permis aux banques de la zone d’améliorer leur efficacité technique. L’évolution de leur productivité est avant tout expliquée par les progrès technologiques existants dans le secteur bancaire de l’espace UEMOA. Troisièmement, les banques de petite taille de la zone UEMOA font plus d’efforts pour réduire la consommation des inputs que celles de grande taille. Par ailleurs, l’efficience d’échelle augmente pour ensuite descendre plus bas qu’à son niveau initial. Cette observation révèle l’existence d’une taille optimale au-delà de laquelle les banques subiraient des déséconomies d’échelle. Quatrièmement, les banques domestiques privées ont un léger avantage en termes d’efficience technique globale et d’efficacité d’échelle sur les banques étrangères tandis que les banques d’Etat ont enregistré les plus faibles scores en termes d’efficacité et de productivité. L’analyse des déterminants des scores d’efficacité montre que l’origine de la propriété, la taille des banques et l’étendue du réseau bancaire ne constituent guère des facteurs déterminants de l’efficacité des banques, du moins pour ce qui concerne les pays de l’UEMOA. En revanche, l’efficacité est influencée par le ratio de capitalisation des banques de l’Union. Enfin, la structure du portefeuille d’actifs des banques et la part des dépôts dans le total bilan sont des variables qui se sont avérées déterminantes aussi bien de l’efficacité technique globale que de l’efficacité technique pure. The purpose of this study is firstly to measure the effects of financial reforms in banks productivity and efficiency in the WAEMU area during the 1996-2006 period, and secondly, to draw the mains managerial determinants of banks efficiency. The productivity and efficiency scores are estimated through the Data Envelopment Analysis (DEA). Our empirical results show firstly that pure technical inefficiencies are higher than scale inefficiencies in all the countries of the area except for Senegal. Thus, the inefficiency stems rather from an under-use of inputs than from an inappropriate return to scale. Secondly, we notice a growth of the global productivity factors which is essentially due to the positive variation of technological progress. Consequently, financial reforms did not permit to banks to increase their technical efficiency. Thirdly, small banks make more efforts to reduce their inputs consumption than great banks. One the other hand, scale efficiency at first increases to decrease then below its initial level. This observation means that there is an optimal size beyond which banks would undergo diseconomies of scale. Fourthly, private domestic-owned banks have a slight advantage on foreign banks in terms of global technical efficiency and scale efficiency while State-owned banks recorded the weakest efficiency and productivity scores. We furthermore conclude that the ownership’s origin, the size of banks and the breadth of the financial network are not much determinant factors of banks efficiency, at least in the WAEMU countries. However, the efficiency is influenced by the capitalization’s ratio of the banks of the Union. Finally, the structure of the banks' portfolio of assets and the proportion of their deposits in the total balance are revealed to be determinants of global as well as pure technical efficiency.banks, efficiency, productivity, data envelopment analysis, financial reforms

Functional response and life history parameters of Apanteles taragamae, a larval parasitoid of Maruca vitrata

The legume pod borer Maruca vitrata Fabricius (Lepidoptera: Crambidae) is a serious pest of cowpea in West-Africa. The parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) that originates from Taiwan is a potential candidate for biological control of M. vitrata. We investigated under laboratory conditions the functional response of the parasitoid by offering each experienced female 10, 20, 30 and 40 larvae of M. vitrata. We studied the influence of different host larval ages on the development, longevity, sex ratio, lifetime fecundity and parasitization rate of the wasp. In a comparative study, we also investigated the life history of A. taragamae and M. vitrata at different temperatures in the range of 20–30C. The parasitoid successfully parasitized two- and three-day-old host larvae (first and second instars). Younger larvae (one-day-old) were parasitized to a lesser extent, and only males developed in them. Older larvae were not parasitized, partly because of defensive host behaviour. The success of arasitization was positively correlated with the density of two-day-old M. vitrata larvae. Parasitoid developmental time and longevity decreased with increasing temperature. The intrinsic rate of population increase (rm) exhibited an optimum curve with a maximum at 24–28C. For the host M. vitrata, rm was maximal at temperatures of 26–30C. The data are discussed in the context of the potential of A. taragamae for biological control of M. vitrata

An assessment of learning gains from educational animated videos versus traditional extension presentations among farmers in Benin*

Article purchasedThis study compared the efficacy of linguistically and dialectically localized animated educational videos (LAV) against traditional learning extension (TLE) presentations for learning gains of knowledge around agricultural- and healthcare-related topics within a rural population in Benin. While both approaches demonstrated learning gains, LAV resulted in significantly higher test scores and more detailed knowledge retention. A key contribution of this research, moreover, involves the use of mobile phone technologies to further disseminate educational information. That is, a majority of participants expressed both a preference for the LAV teaching approach and a heightened interest in digitally sharing the information from the educational animations with others. Because the animations are, by design, readily accessible to mobile phones via Africa’s explosively expanding digital infrastructure, this heightened interest in sharing the animated videos also transforms each study participant into a potential a learning node and point of dissemination for the educational video’s material as well

Assessing nontarget effects and host feeding of the exotic parasitoid Apanteles taragamae, a potential biological control agent of the cowpea pod borer Maruca vitrata

Article PurchasedApanteles taragamae Viereck is a larval parasitoid introduced in Benin for classical biological control of the cowpea pod borer Maruca vitrata Fabricius. In the laboratory, we evaluated the effects of A. taragamae on non-target herbivore species, and on another parasitoid of M. vitrata, i.e. the egg-larval parasitoid Phanerotoma leucobasis Kriechbaumer. Furthermore, we addressed the host feeding behaviour of A. taragamae. The host specificity of A. taragamae was assessed by offering six other lepidopteran species to the wasp. The competitive ability of A. taragamae was studied by providing the wasp with one- and two-days-old M. vitrata larvae that had hatched from eggs previously parasitized by P. leucobasis. Controls consisted of eggs and larvae offered only to P. leucobasis and A. taragamae, respectively. None of the other six lepidopteran species was successfully parasitized by A. taragamae. The larval parasitoid A. taragamae outcompeted the egg-larval parasitoid P. leucobasis when offered two-days-old host larvae. Competition between the two parasitoid species did not significantly affect one-day-old host larvae that were less suitable to A. taragamae. Host feeding by A. taragamae did not affect survival of one-day-old or two-days-old M. vitrata larvae. However, the percentage parasitism of two-days-old larvae was significantly reduced when exposed to female A. taragamae wasps that had been starved during 48 h. The data are discussed with regard to host specificity, host feeding patterns and to factors underlying the outcome of intrinsic competition between parasitoid species

Functional response and life history parameters of Apanteles taragamae, a larval parasitoid of Maruca vitrata

Open Access JournalThe legume pod borer Maruca vitrata Fabricius (Lepidoptera: Crambidae) is a serious pest of cowpea in West-Africa. The parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae) that originates from Taiwan is a potential candidate for biological control of M. vitrata. We investigated under laboratory conditions the functional response of the parasitoid by offering each experienced female 10, 20, 30 and 40 larvae of M. vitrata. We studied the influence of different host larval ages on the development, longevity, sex ratio, lifetime fecundity and parasitization rate of the wasp. In a comparative study, we also investigated the life history of A. taragamae and M. vitrata at different temperatures in the range of 20–30°C. The parasitoid successfully parasitized two- and three-day-old host larvae (first and second instars). Younger larvae (one-day-old) were parasitized to a lesser extent, and only males developed in them. Older larvae were not parasitized, partly because of defensive host behaviour. The success of parasitization was positively correlated with the density of two-day-old M. vitrata larvae. Parasitoid developmental time and longevity decreased with increasing temperature. The intrinsic rate of population increase (rm) exhibited an optimum curve with a maximum at 24–28°C. For the host M. vitrata, rm was maximal at temperatures of 26–30°C. The data are discussed in the context of the potential of A. taragamae for biological control of M. vitrata

Farmers knowledge and control of two major pests: Helicoverpa armigera (Hübner) (Lepidoptera, Noctuidae) and Aphis gossypii (Glover) (Homoptera: Aphididae) in five agroecological zones in Benin (West Africa)

A survey study was performed in five agro-ecological zones in Benin to assess farmers’ knowledge and perceptionon the identification, damage recognition, applied control methods of two cotton insect pests Helicoverpaarmigera Hübner and Aphis gossypii Glover. A total of 200 farmers were interviewed in the five agroecologicalzones in Benin, using semi-structured questionnaire interviews. Results revealed sound knowledge of farmers onthe identity of H. armigera and A. gossypii. Farmers easily recognized H. armigera through its damage ondifferent plant organs while A. gossypii was known only at high infestation stage. Moreover, many crops arelisted as host plants for H. armigera and A. gossypii with different economic injuries. Control of these insectpests was done mainly by the use of chemicals with various application numbers and frequencies. The mostapplied chemicals for the control of H. armigera on cotton were Nurelle D 236 EC in zone 4 and 6, Thunder145O-Teq in zone 5 and Tihan 175 O-Teq in zone 2, while protection against A. gossypii was done using mostly Thian175 O-Teq except in the zone 6 where Fanga was used. The time interval between two treatments was 3-14 daysdepending on the product in use, the target insect and the agro-ecological zone. The effectiveness of the differentproducts was diversely appreciated. Farmers claimed to be aware of the so many side effects of chemicalsapplication. In organic cotton area, alternative method consisting of the use of botanical extracts was beingexperimented

Extraction of Zero-Point Energy from the Vacuum: Assessment of Stochastic Electrodynamics-Based Approach as Compared to Other Methods

In research articles and patents several methods have been proposed for the extraction of zero-point energy from the vacuum. None of the proposals have been reliably demonstrated, yet they remain largely unchallenged. In this paper the underlying thermodynamics principles of equilibrium, detailed balance, and conservation laws are presented for zero-point energy extraction. The proposed methods are separated into three classes: nonlinear processing of the zero-point field, mechanical extraction using Casimir cavities, and the pumping of atoms through Casimir cavities. The first two approaches are shown to violate thermodynamics principles, and therefore appear not to be feasible, no matter how innovative their execution. The third approach, based upon stochastic electrodynamics, does not appear to violate these principles, but may face other obstacles. Initial experimental results are tantalizing but, given the lower than expected power output, inconclusive.Comment: 18 pages including 12 figure