Effet du chlorure de sodium sur la germination de graines de Ricinus communis L.

Ricinus communis L (ricin) figure parmi les espèces du Programme biocarburant au  Sénégal. Sa culture sur des terrains incultes (terres salées) constitue une alternative pour éviter une concurrence sur les terres à vocation agricole. C’est pourquoi le taux de germination (TG) de sept accessions de graines de ricin a été étudié pendant 15 jours sous des concentrations croissantes de NaCl (0; 20; 50; 80; 100; 150 et 200 mM). Les résultats ont montré une large variabilité de tolérance au sel au stade de la germination. Les accessions 3 et 8 ont été très sensibles avec des TG réduits seulement à la concentration 20 mM NaCl. Les accessions 1, 6 et 7 n’ont pas toléré la concentration 50 mM. L’accession 5 n’a toléré que les teneurs < 80 mM. L’accession 4 a germé dans les milieux ≤ 100 mM NaCl. Elle n’a manifesté une perte significative de TG qu’en présence de 150 mM NaCl. Elle a été la moins affectée par l’effet ralentisseur du sel sur la vitesse de germination. Ces résultats permettent de dire que le mode d’action de NaCl sur la germination est de nature osmotique et/ou toxique.Mots clés : Ricin, espèce, biocarburant, tolérance au sel, teneur en sel, Sénégal

Caractérisation physico-chimique de la gomme Sterculia de trois localités de la région de Tambacounda au Sénégal

La gomme sterculia est produite par Sterculia setigera Del. en Afrique. Ses propriétés physicochimiques changent suivant divers facteurs dont l’influence sur sa qualité a été peu étudiée. C’est dans cette perspective que l’humidité, le pH, le pouvoir gonflant et la viscosité de cette gomme ont été évalués au Sénégal (Daoudi, Malem niani et Bala). Les résultats ont montré que son humidité varie en fonction du phénotype (écorce claire ou foncée). Elle a été plus élevée sur la gomme de la période sèche-chaude à Daoudi mais elle n’a pas changé suivant le site après un an de conservation. Son pH a varié en fonction de l’interaction période de saignée- couleur de l’écorce à Malem Niani alors qu’à Daoudi il a varié suivant la période de saignée seulement. A Malem, son gonflement a aussi varié suivant l’interaction période de saignée-couleur de l’écorce. Après un an de conservation (température ambiante), son pouvoir gonflant a diminué dans tous les sites. Sa viscosité a été 3,5 fois plus élevée à Bala qu’à Daoudi et Malem Niani. Ces résultats ont permis d’acquérir de nouvelles connaissances et d’identifier Bala comme ayant la meilleure qualité de gomme par rapport aux deux autres sites.Mots clés: Acidité, Humidité, pouvoir de gonflement, Sterculia setigera Del., Tambacounda, viscosit&#233

Assessment of Vitamin A Status of Preschool Children in a Sub-Saharan African Setting: Comparative Advantage of Modified Relative-dose Response Test

A nationally-representative sample of 2,696 preschool children living in Congo was examined during August-September 2003 to determine the rates of vitamin A deficiency. Ninety clusters of 30 children, aged six months to six years, were selected, using a randomized two-level cluster-sampling method. Vitamin A deficiency was determined by assessing the prevalence of active xerophthalmia (nightblindness and/or Bitot spots) in the cross-over sample of 2,696 individuals. A semi-quantitative seven-day dietary questionnaire was concurrently applied to the mothers of children enrolled to estimate the latter's consumption of vitamin A-rich food. Vitamin A status was assessed by performing the modified relative dose-response test (MRDR) on dried blood spots (DBS) from a subsample of 207 children aged less than six years and the impression cytology with transfer (ICT) test on a subsample of 1,162 children. Of the children enrolled, 5.2% suffered from nightblindness, 8.0% had Bitot spots, and 2.5% had other vitamin A deficiency sequellae. Fifty-three percent of the ICT tests showed the presence of vitamin A deficiency. The biochemical MRDR test showed that the vitamin A status of 30% of the study children was critical. Twenty-seven of them had retinol levels of <10 μg/dL [mean±standard deviation (SD) 7.02±2.0 μg/dL], and 50% had retinol levels of 10-20 μg/dL (mean±SD 14.2±2.83 μg/dL). The poor health status and low rates of consumption of vitamin A-rich food are the main factors determining critical status. Vitamin A deficiency, reflecting poor nutrition and health, is a serious public-health issue among children aged less than six years in Congo

Sterculia setigera Del.: influence de quelques facteurs sur la production de gomme

La gomme sterculia est produite par Sterculia setigera en Afrique. Elle est largement consommée par les populations. Cependant, les pratiques traditionnelles d’exploitation de cette gomme (appelée localement gomme mbepp) par les populations locales constituent la cause principale de la dégradation des peuplements de Sterculia setigera au Sénégal et dans les pays où pousse l’espèce (Mali, Gambie, Niger…). Par ailleurs, peu d’études ont été effectuées dans la région Sahélienne sur les facteurs pouvant influer directement sur la production de cette gomme. Ainsi, la présente recherche qui avait pour objet d’acquérir de nouvelles connaissances sur l’espèce, a étudié, dans une série d’essais à un ou plusieurs facteurs, l’influence de quatre facteurs : la période de saignée (avec quatre  niveaux), le site de récolte, la profondeur des entailles et le diamètre du tronc à 1,30 m (avec deux niveaux pour chacun des trois derniers facteurs)sur la production de gomme mbepp brute, la quantité de gomme nettoyée et le pourcentage de gomme. Les dispositifs expérimentaux ont été  installés dans deux sites situés en forêt naturelle dans la région de Tambacounda (Malem Niani et Daoudi). Les résultats ont montré que le rendement en gomme brute a significativement varié en fonction du site (Daoudi : 186,17 g/arbre contre 149,6 g/arbre à Malem Niani). A Daoudi, la quantité de gomme brute a été trois fois plus élevée avec une saignée de 5 cm de profondeur (62,61 g) qu’avec une saignée de 3 cm (21,54 g). A Malem Niani, les arbres de gros diamètre ont produit plus de gomme (78,50 %) que les arbres de petit diamètre (34,56%) durant la période chaude. Le pourcentage annuel moyen de gomme par arbre a été plus élevé chez les arbres de gros diamètre (83,24 %) et plus faible (68,76 %) sur les arbres de petit diamètre. Les résultats obtenus à travers les différents essais conduits en milieu réel permettront (1) d’assurer une meilleure exploitation de la gomme ainsi qu’une meilleure préservation de la ressource et (2) d’améliorer les conditions de vie des populations locales.Mots-clés : sterculia setigera, mbepp, karaya, saignée

Auditory and Visual Durations Load a Unitary Working-Memory Resource

Items in working memory are typically defined by various attributes, such as colour (for visual objects) and pitch (for auditory objects). The attribute of duration can be signalled by multiple modalities, but has received relatively little attention from a working-memory perspective. While the existence of specialist stores (e.g., the phonological loop and visuospatial sketchpad) is often asserted in the wider working-memory literature, the interval-timing literature has more often implied a unitary (amodal) store. Here we combine two modelling frameworks to probe the basis of working memory for duration; a Bayesian-observer framework, previously used to explain behaviour in duration-reproduction tasks, and mixture models, describing distributions of continuous reports about items in working memory. We modelled different storage mechanisms, such as a limited number of fixed-resolution slots or a resource spread between items at a cost to resolution, in order to ask whether items from different sensory modalities are maintained in separate, independent stores. We initially analysed data from 32 participants, who memorised between one and eight items before reproducing the duration of a randomly selected target. In separate blocks, items could be all visual, all auditory, or an alternating mixture of both. A small control experiment included a further condition with precuing of target modality. Certain kinds of slot models, resource models, and combination models incorporating both mechanisms could account for the data. However, looking across all plausible models, the decline in performance with increasing memory load was most consistent with a single store for event durations, regardless of stimulus modality

Criblage in vitro des graines d’accessions locales de ricin (Ricinus communis L.) en conditions de stress salin

Le ricin (Ricinus communis L.) est une plante peu exigeante dont la culture offre d’énormes potentialités économiques pour les exploitants agricoles sénégalais. L’identification de génotypes performants avec des rendements acceptables en conditions de stress salin constitue une des solutions pour promouvoir cette culture sur des sols inaffectés aux cultures vivrières. Quatre accessions locales de ricin ont été cultivées durant un mois sur le milieu de Murashige et Skoog (MS) modifié et additionné de 0 ; 25 ; 50 ; 100 et 150 mM de chlorure de sodium (NaCl). Les réponses des accessions ont été évaluées en conditions in vitro sur la base de paramètres morphologiques, biochimiques et de survie des vitroplants. L’effet de la salinité sur ces paramètres mesurés a permis de classer les accessions en groupe tolérant (acc1), moyennement tolérant (acc7) et sensible (acc3 et acc4). La concentration 50 mM de NaCl a été identifiée comme un seuil de tolérance critique et discriminant permettant une classification des accessions de ricin selon leur sensibilité au NaCl. La biomasse aérienne est apparue comme un critère pertinent pour classer les accessions de ricin. Les mesures des teneurs en chlorophylle des feuilles des vitroplants ont permis d’aboutir à la même classification des groupes.Mots clés: criblage, Ricinus communis, salinité, SénégalEnglish Title:  In vitro screening of local accessions of castor bean seeds (Ricinus communis l.) Under conditions of salinity stressEnglish AbstractCastor bean (Ricinus communis L.) is an undemanding plant whose cultivation has enormous economic potential for Seneg alese farmers. The identification of efficient genotypes tolerant to salt stress condition could constitute a significant result to promote ricin culture specifically in margin soils. Four local accessions of castor were cultivated, using in vitro conditions for four weeks on MS modified medium supplemented with 0, 25, 50, 100, 150 mM NaCl. In vitro plants responses to salinity were recorded in terms of morphological and biochemical parameters and the rate of plant survival. The effect of different levels of salinity on these parameters was used to classify the accessions in tolerant group (acc1), moderately tolerant (acc7) and sensitive (acc3 and acc4). The concentration 50 mM of NaCl was identified as a discriminant level for castor accessions classification and a critical level of tolerance. The in vitro plants shoot biomass, appeared a relevant parameter to be used for classification of castor accessions under in vitro conditions. The content of leaf chlorophyll for in vitro plants confirmed the classification of Castor bean accessions obtained with morphological parameters according to their sensitivity to the salinity.Keywords: screening, Ricinus communis, salinity, Senega

Satisfação e qualidade de serviço prestado pela EMAE no fornecimento de água em STP

A água é um recurso essencial à vida e um fator chave para o desenvolvimento sustentável, para a saúde alimentar e para o progresso económico. Em STP, face ao contexto de constrangimentos diversos da administração pública e das crescentes exigências da população com a melhoria do fornecimento de água, a qualidade dos serviços públicos prestados pela EMAE é uma temática atual e muito relevante. Assim, a presente investigação teve como objetivo conhecer a opinião dos clientes/cidadãos em relação à satisfação e à qualidade do serviço de fornecimento de água prestado pela EMAE. Para isso, realizou-se uma investigação de natureza descritiva, com levantamento de dados de fontes primárias (questionário realizado aos clientes e entrevista não estruturada a um antigo funcionário da empresa e relatos de outros) e secundárias (documentos internos da EMAE e revisão da literatura). Os fatores de satisfação dos utilizadores dos serviços de fornecimento de água da EMAE foram analisados em conformidade com as dimensões do modelo SERVQUAL. A análise dos resultados evidenciou que a avaliação da qualidade dos serviços feita pelos clientes é muito má ou média, mostrandose estes insatisfeitos. No que respeita à resolução rápida de avarias, ao fornecimento de água com qualidade, à informação prestada e à faturação foi considerada muito má. Quanto à facilidade e resposta a reclamações, tempo de espera e privacidade no atendimento e apresentação dos funcionários, confiança nas informações fornecidas e, informação clara das faturas foi entendida como média. Apesar das limitações relacionadas ao fato da amostra ser de conveniência, pode concluir-se não estarem os cidadãos englobados no estudo, satisfeitos com a qualidade dos serviços da EMAE no fornecimento de água potável à população de STP; ABSTRACT: Water is an essential resource for life and is a key factor for sustainable development, for food health and for economic progress. In STP, given the context of various constraints on public administration and the growing demands of the population with the improvement of water supply, the quality of public services provided by EMAE is a current and very relevant issue. Thus, the present investigation aimed to know the opinion of customers / citizens in relation to the satisfaction and quality of the water supply service provided by EMAE. For this, a descriptive investigation was carried out, with data collection from primary sources (questionnaire carried out to customers and reports from former employees of the company) and secondary sources (internal documents of EMAE and literature review). The satisfaction factors of users of the EMAE water supply services were analyzed in accordance with the five dimensions of the SERVQUAL model. The analysis of the results showed that the assessment of the quality of services by customers is very poor or average, showing these dissatisfied. Regarding the quick resolution of faults, the provision of quality water, the information provided and billing was considered very bad. As for the ease and response to complaints, waiting time and privacy in the service and presentation of employees, confidence in the information provided and clear information on the invoices was understood as average. Despite the limitations related to the fact that the sample is of convenience, it can be concluded that the citizens are not included in the study, satisfied with the quality of EMAE services in the supply of drinking water to the population of STP

In vitro micrografting of Sterculia setigera Del.

An in vitro procedure micrografting of adult scions of Sterculia setigera was developed to overcome low rooting in adult shoot. Axenic micro shoots of 0.5 cm length taken from adult trees as scions were grafted on seedlings rootstocks cultured on MS medium. 100% success was obtained with micrografts using adult apex as scions. Upon three cycles of in vitro micrografting, rejuvenation capacities of S. setigera was recovered as shown by vigour, length and rooting of shoots grown from grafts cultured on MS medium compared to seedlings. Successful micrografts were transferred to plastic pots containing soil under mist house conditions before they were finally exposed to an external environment. 80% of the plantlets survived in the nursery.Keywords: Sterculia setigera, micrografting, rejuvenation, rootin

Physiological Status of Fattening Bali Cattle Feeding a Concentrate Containing Gliricidia sepium Leaves Meal Fortified with Vitamin B-Complex and Vermicide

This research has been conducted at Oeletsala village, for 10 weeks from 23 November 2015 to 23 January 2016, comprised of 2 weeks preliminary and 8 weeks for data collection. The aim of the research was to study the effect of feeding a Gliricidia sepium leaves meal concentrate fortified with B. complex vitamin and vermicide on rectal temperature, respiratory frequency, and heart rate of fattening Bali cattle. Experimental animals used were nine young male Bali cattle of 1.5-2 years old, with an initial body weight ranging from 82 to 124 kg (KV=15.114%) in average of 98.7±14.93 kg. The experimental design used was Randomized Block Design with three treatments and three replications. Those treatments were R0 = leaves of Leucaena leucocephala and Ceiba pentandra+ native grass ad libitum (as commonly practiced by local farmers), R1 = R0 + 2 kg concentrate, and R2 = R1 + B. complex vitamin, and vermicide. Statistical analysis showed that there was no significant effect of the treatments on rectal temperature, respiratory frequency, and heart rate of the fattening Bali cattle(P ≤ 0.05).In conclusion, there was no significant effect of Gliricidia sepium leaves meal concentrate, vitamin B. complex, and vermicide on rectal temperature, respiratory frequency, and heart rate of the fattening Bali cattle. Keywords: concentrate, B complex vitamin, worm vermicide, rectal temperature, respiratory frequency, and heart rat