Impact of the insecticide endosulfan on growth of the African giant snail Achatina achatina (L.)

The impact of the insecticide endosulfan was assessed on the growth of the African giant snails, litterliving animals found in cocoa fields throughout tropical Africa. Two doses of endosulfan, C1, 6.25 a.i g/l and C2, 12.50 a.i g/l were applied twice with one month of interval to the litter of the snails. After quarantine, snails were allowed to feed on this litter and the elongation of their shells as well as their growth was measured every nine days. The results, daily weight gain (g/j) of -0.028 ± 0.004 for C1 and - 0.033 ± 0.007 for C2 showed that snails which received endosulfan in their feed had a very weak growth compared to the control one, which have a daily weight gain of 0.032 ± 0.006. The product seems to disrupt weight regulation. But the insecticide had little influence on the shell elongation. High dose o endosulfan reduced more the weight gain and shell elongation compared to the recommended dose for insects control in cocoa plantation. These results implied that the repeated application of endosulfan for pest control in cocoa plantations may impair the growth of African giant snails.Key words: Achatina, endosulfan, pest control, insecticide, cocoa

Acceptabilite´ du test VIH propose´ aux nourrissons dans les services pe´ diatriques, en Coˆ te d’Ivoire, Significations pour la couverture du diagnostic pe´diatrique

Proble`me: Le de´pistage VIH chez les enfants a rarement e´te´ au centre des pre´occupations des chercheurs. Quand le de´pistage pe´diatrique a retenu l’attention, cela a e´te´ pour e´clairer seulement sur les performances diagnostiques en ignorant meˆme que le test pe´diatrique comme bien d’autres peut s’accepter ou se refuser. Cet article met au coeur de son analyse les raisons qui peuvent expliquer qu’on accepte ou qu’on refuse de faire de´pister son enfant.Objectif: Etudier chez les parents, les me`res, les facteurs explicatifs de l’acceptabilite´ du test VIH des  nourrissons de moins de six mois.Me´thodes: Entretien semi-directif a` passages re´pe´te´s avec les parents de nourrissons de moins de six mois dans les formations sanitaires pour la pese´e/vaccination et les consultations pe´diatriques avec proposition syste´matique d’un test VIH pour leur nourrisson.Re´sultats: Nous retenons que la re´alisation effective du test pe´diatrique du VIH chez le nourrisson repose sur trois e´le´ments. Primo, le personnel de sante´ par son discours (qui de´note de ses connaissances et  perceptions meˆme sur l’infection) oriente´ vers les me`res influence leur acceptation ou non du test. Secundo, la me`re qui par ses connaissances et perceptions meˆme sur le VIH, dont le statut particulier, l’impression de bien-eˆtre chez elle et son enfant influence toute re´alisation du test pe´diatrique VIH. Tertio, l’environnement conjugal de la me`re, particulie`rement caracte´rise´ par les rapports au sein du couple, sur la facilite´ de parler du test VIH et sa re´alisation chez les deux parents ou chez la me`re seulement sont autant de facteurs qui influencent la re´alisation effective du de´pistage du VIH chez l’enfant. Le principe pre´ventif du VIH, et le de´sir de faire tester l’enfant ne suffisent pas a` eux seuls pour aboutir a` sa re´alisation effective, selon certaines me`res confronte´es au refus du conjoint. A l’oppose´, les autres me`res refusant la re´alisation du test  pe´diatrique disent s’y opposer ; bien entendu, meˆme dans le cas ou` le conjoint l’accepterait.Discussion: Les me`res sont les principales mises en cause et craignent les re´primandes et la stigmatisation. Le pe`re, le conjoint peut eˆtre un obstacle, quand il s’oppose au test VIH du nourrisson, ou devenir le facilitateur de sa re´alisation s’il est convaincu. Le positionnement du pe`re demeure donc essentiel dans la question de l’acceptabilite´ du VIH pe´diatrique. Les me`res en ont conscience et pre´sagent des difficulte´s a` faire  de´pister ou non les enfants sans avis pre´alable du conjoint a` la fois pe`re, et chef de famille.Conclusion: La question du de´pistage pe´diatrique du VIH, au terme de notre analyse, met en face trois e´le´ments qui exigent une gestion globale pour assurer une couverture effective. Ces trois e´le´ments n’existeraient pas sans s’influencer, donc ils sont constamment en interaction et empeˆchent ou favorisent la re´alisation ou non du test pe´diatrique. Aussi, dans une intention d’aboutir a` une couverture effective du de´pistage VIH des nourrissons, faut-il tenir compte d’une gestion harmonieuse de ces trois e´le´ments: La premie`re, la me`re seule (avec ses connaissances, ses perceptions), son environnement conjugal (de  proposition du test inte´grant 1- l’e´poux et / ou pe`re de l’enfant avec ses perceptions et connaissances sur l’infection 2- la facilite´ de parler du test et sa re´alisation chez les deux ou un des parents, la me`re) et les connaissances, attitudes et pratiques du personnel de l’e´tablissement sanitaire sur l’infection du VIH.Recommandations: Nos recommandations proposent une rede´finition de l’approche du VIH/sida vers des familles expose´es au VIH et une inte´gration plus accentue´e du pe`re facilitant leur propre acceptation du test VIH et celle de leur enfant.Mots cle´s: Acceptabilite´, Test VIH, Enfants, Nourrissons Problem: HIV testing in children had rarely been a central concern for researchers. When pediatric tracking retained the attention, it was more to inform on the diagnosis tools performances rather than the fact the pediatric test can be accepted or refused. This article highlights the parent’s reasons which explain why pediatric HIV test is accepted or refused.Objective: To study among parents, the explanatory factors of the acceptability of pediatric HIV testing among infant less than six months.Methods: Semi-structured interview with repeated passages in the parents of infants less than six months attending in health care facilities for the pediatric weighing/vaccination and consultations.Results: We highlight that the parent’s acceptance of the pediatric HIV screening is based on three elements.Firstly, the health care workers by his speech (which indicates its own knowledge and perceptions on the infection) directed towards mothers’ influences their acceptance or not of the HIV test. Secondly, the mother who by her knowledge and perceptions on HIV, whose particular status, give an impression of her own wellbeing for her and her child influences any acceptance of the pediatric HIV test. Thirdly, the marital environment of the mother, particularly characterized by the ease of communication within the couple, to speak about the HIV test and its realization for the parents or the mother only are many factors which influence the effective realization of the pediatric HIV testing. The preventive principle of HIV transmission and the desire to realize the test in the  newborn are not enough alone to lead to its effective realization, according to certain mothers confronted with the father’s refusal. On the other hand, the other mothers refusing the realization of the pediatric test told to be opposed to it; of course, even if their partner would accept it.Discussion: The mothers are the principal facing the pediatric HIV question and fear the reprimands and stigma. The father, the partner could be an obstacle, when he is opposed to the infant HIV testing, or also the facilitator with his realization if he is convinced. The father position thus remains essential face to the question of pediatric HIV testing acceptability. The mothers are aware of this and predict the difficulties of achieving their infant to be tested without the preliminary opinion of their partner at the same time father, and head of the family.Conclusion: The issue of pediatric HIV testing, at the end of our analysis, highlights three elements which require a comprehensive management to improve the coverage of pediatric HIV test. These three elements would not exist without being influenced; therefore they are constantly in interaction and prevent or support the realization or not pediatric test. Also, with the aim to improve the pediatric HIV test coverage, it is necessary to take into account the harmonious management of these elements. Firstly, the mother alone (with her knowledge, and perceptions), its marital environment (with the proposal of the HIV test integrating (1) the partner and/or father with his perceptions and knowledge on HIV infection and (2) facility of speaking about the test and its realization at both or one about the parents, the mother) and of the knowledge, attitudes and practices about the infection of health care workers of the sanitary institution.Recommendations: Our recommendations proposed taking into account a redefinition of the HIV/AIDS approach towards the families exposed to HIV and a more accentuated integration of the father facilitating their own HIV test acceptation and that of his child.Keywords: acceptability, HIV testing, children, infantsArticle in French

A policy-based management architecture for flexible service deployment in active networks

This paper describes a dynamic, scalable and extensible policy-based network management (PBNM) system that is fully integrated with a service provisioning architectures for active networks. The key result is network customisation according to the needs of the different service providers and its end users. Our component-based service provisioning architecture enables us to render service- and user-specific requirements, across single/multiple administrative domains, at deployment time and to dynamically map service components onto the network using the corresponding management policies. The architecture presented in this paper describes the approach undertaken by the IST-FAIN research project as well as the main issues that we encounter in developing and integrating the PBNM with the service provisioning mechanism

Response of CsI(Tl) scintillators over a large range in energy and atomic number of ions (Part I): recombination and delta -- electrons

A simple formalism describing the light response of CsI(Tl) to heavy ions, which quantifies the luminescence and the quenching in terms of the competition between radiative transitions following the carrier trapping at the Tl activator sites and the electron-hole recombination, is proposed. The effect of the delta rays on the scintillation efficiency is for the first time quantitatively included in a fully consistent way. The light output expression depends on four parameters determined by a procedure of global fit to experimental data.Comment: 28 pages, 6 figures, submitted to Nucl. Inst. Meth.

GENETIC EVALUATION OF SEED TRAITS FROM INTRASPECIFIC CROSSING OF GENETICALLY DISTINCT WATERMELON VARIETIES

Citrullus lanatus (Thunb.) Matsumura and Nakai (Cucurbitaceae) is an important cucurbit crop worldwide. Global production of watermelon is about 90 million metric tonnes per annum, making it among the top five most consumed fresh fruits. The objective of this study was to evaluate seed variability in different segregating populations, and determine heritability of traits of watermelon. Interspecific crosses were made between two cultivars of C. lanatus (Bebu and Wl\ueawl\uea Small Seeds (WSS) were performed at Research Station of Nangui Abrogoua University in Abidjan, C\uf4te d\u2019Ivoire. There was wide variability between parental, F1, BC1 (first generation of back-crossing) and F2 seeds. Seeds of all hybrid populations were intermediate versus those of the parents. Also, crossing did not affect F1 and F2 seed characters, but affected those of BC1 because of maternal effects. Thus, back-crossing on Bebu cultivar produced seeds which looked like those of Bebu; while back-crossing on WSS cultivar produced seeds similar to those of WSS. Principal Component Analysis (PCA) and individuals repartitioning revealed that Bebu and WSS cultivars were genetically distinct and showed three main groups: two groups from each parental line and one from a recombinant line (hybrids). F2 population had a wide individual\u2019s dispersion, and contained seeds of all other populations. High heritability was observed for all evaluated characters.Citrullus lanatus (Thunb.) Matsumara et Nakai (Cucurbitac\ue9e) est une importante cucurbite dans le monde entier. La production annuelle globale est d\u2019environ 90 million de tonne, ce qui place cette culture parmi les cinq fruits les plus consomm\ue9s crus. L\u2019objectif de cette \ue9tude est d\u2019\ue9valuer la variabilit\ue9 des graines de diff\ue9rentes populations en s\ue9gr\ue9gation et de d\ue9terminer l\u2019h\ue9ritabilit\ue9 des caract\ue8res chez l\u2019esp\ue8ce Citrullus lanatus. Pour cela, un croisement intersp\ue9cifique entre deux cultivars de Citrullus lanatus (Bebu et Wl\ueawl\uea \ue0 petites graines (WSS)) a \ue9t\ue9 effectu\ue9 \ue0 la station de recherche de l\u2019Universit\ue9 Nangui Abrogoua d\u2019Abidjan (C\uf4te d\u2019Ivoire). Il existe une variabilit\ue9 importante entre les graines parentales, F1, BC1 (premi\ue8re g\ue9n\ue9ration de back-cross) et F2. Les graines de toutes les populations hybrides sont interm\ue9diaires \ue0 celles des parents. Aussi, le sens de croisement n\u2019affecte pas les caract\ue8res des graines F1 et F2 mais affecte ceux des graines BC1 \ue0 cause de l\u2019effet maternel. Ainsi, un backcross effectu\ue9 sur le cultivar Bebu produit des graines semblables aux graines de Bebu tandis qu\u2019un backcross effectu\ue9 sur le cultivar WSS produit des graines semblables aux graines de WSS. L\u2019Analyse en Composantes Principales et la r\ue9partition des individus dans le plan permettent d\u2019observer que les cultivars Bebu et WSS sont g\ue9n\ue9tiquement distincts et montrent trois principaux groupes\ua0: deux groupes de chaque type parental et un type recombinant (hybride). La population F2 a une large dispersion et se compose des graines de toutes les autres populations. Une forte h\ue9ritabilit\ue9 a \ue9t\ue9 observ\ue9e pour tous les caract\ue8res \ue9valu\ue9s. En somme, la variabilit\ue9 des graines observ\ue9es dans les populations en s\ue9gr\ue9gation chez C. lanatus pourrait \ueatre due \ue0 des effets g\ue9n\ue9tique

Evidence for Spinodal Decomposition in Nuclear Multifragmentation

Multifragmentation of a ``fused system'' was observed for central collisions between 32 MeV/nucleon 129Xe and natSn. Most of the resulting charged products were well identified thanks to the high performances of the INDRA 4pi array. Experimental higher-order charge correlations for fragments show a weak but non ambiguous enhancement of events with nearly equal-sized fragments. Supported by dynamical calculations in which spinodal decomposition is simulated, this observed enhancement is interpreted as a ``fossil'' signal of spinodal instabilities in finite nuclear systems.Comment: 4 pages, 4 figures, to be published in Phys. Rev. Letter

Multifragmentation process for different mass asymmetry in the entrance channel around the Fermi energy

The influence of the entrance channel asymmetry upon the fragmentation process is addressed by studying heavy-ion induced reactions around the Fermi energy. The data have been recorded with the INDRA 4pi array. An event selection method called the Principal Component Analysis is presented and discussed. It is applied for the selection of central events and furthermore to multifragmentation of single source events. The selected subsets of data are compared to the Statistical Multifragmentation Model (SMM) to check the equilibrium hypothesis and get the source characteristics. Experimental comparisons show the evidence of a decoupling between thermal and compresional (radial flow) degrees of freedom in such nuclear systems.Comment: 28 pages, 15 figures, article sumitted to Nuclear Physics

Effect of the intermediate velocity emissions on the quasi-projectile properties for the Ar+Ni system at 95 A.MeV

The quasi-projectile (QP) properties are investigated in the Ar+Ni collisions at 95 A.MeV taking into account the intermediate velocity emission. Indeed, in this reaction, between 52 and 95 A.MeV bombarding energies, the number of particles emitted in the intermediate velocity region is related to the overlap volume between projectile and target. Mean transverse energies of these particles are found particularly high. In this context, the mass of the QP decreases linearly with the impact parameter from peripheral to central collisions whereas its excitation energy increases up to 8 A.MeV. These results are compared to previous analyses assuming a pure binary scenario