Chemical and Mineralogical Characterization of the Clayey Sands of Samo and Bingerville in the North of the Lagoon Fault, South of the Ivory Coast, In Road Construction

In Côte d'Ivoire, particularly in the south, the majority of paved and unpaved roads are made of clayey sand, given its availability. However, the early degradation of roads related to a strong sensitivity of this material to the environment (climate, geology and degrees of alteration) and a poor knowledge of the geotechnical properties of this one could slow down their use in road construction. It is within this framework that the work undertaken aims at determining the chemico-mineralogical nature of the clayey sands of the localities of Bingerville and Samo, in the South-East of Côte d'Ivoire. Tests were carried out taking into account the chemical and mineralogical analyses. Chemical elements were determined by atomic absorption spectrometry, colorimetry, complexometry and gravimetry. The determination of organic matter was determined using the Rock-Eval 6 pyrolysis method. The mineralogical composition was determined using a Bruker D8 ADVANCE diffractometer. The chemico-mineralogical analyses show that the clayey sands of Bingerville and Samo are more enriched in silica oxide (SiO2) but less enriched in iron oxide (Fe2O3). All the soils studied have an S/R ratio greater than 2, indicating that these soils are non-lateritic. In addition, the low TOC values between 0.1 and 0.15% by weight, which reflect the extremely low amount of organic matter in these soils, show the possibility of treating these soils with hydraulic binders. In addition, the mineralogy of the studied soils indicates that they are mainly composed of kaolinite and illite

Chemical and Mineralogical Characterization of the Clayey Sands of Samo and Bingerville in the North of the Lagoon Fault, South of the Ivory Coast, In Road Construction

In Côte d'Ivoire, particularly in the south, the majority of paved and unpaved roads are made of clayey sand, given its availability. However, the early degradation of roads related to a strong sensitivity of this material to the environment (climate, geology and degrees of alteration) and a poor knowledge of the geotechnical properties of this one could slow down their use in road construction. It is within this framework that the work undertaken aims at determining the chemico-mineralogical nature of the clayey sands of the localities of Bingerville and Samo, in the South-East of Côte d'Ivoire. Tests were carried out taking into account the chemical and mineralogical analyses. Chemical elements were determined by atomic absorption spectrometry, colorimetry, complexometry and gravimetry. The determination of organic matter was determined using the Rock-Eval 6 pyrolysis method. The mineralogical composition was determined using a Bruker D8 ADVANCE diffractometer. The chemico-mineralogical analyses show that the clayey sands of Bingerville and Samo are more enriched in silica oxide (SiO2) but less enriched in iron oxide (Fe2O3). All the soils studied have an S/R ratio greater than 2, indicating that these soils are non-lateritic. In addition, the low TOC values between 0.1 and 0.15% by weight, which reflect the extremely low amount of organic matter in these soils, show the possibility of treating these soils with hydraulic binders. In addition, the mineralogy of the studied soils indicates that they are mainly composed of kaolinite and illite

Chemical and Mineralogical Characterisation of Clayey Sands from the Ivorian Sedimentary Basin in Road Construction

In Ivory Coast, particularly in the south, most paved and unpaved roads are made of clayey sand, given its availability. The early degradation of roads is related to a strong sensitivity of certain materials to the environment (climate, geology, and degrees of alteration) and a poor knowledge of the geotechnical properties could slow down their use in road construction. Within this framework, this paper focuses on determining the chemico-mineralogical nature of the clayey sands of the localities of Bingerville and Samo, in the South-East of Ivory Coast. Tests were conducted based on the chemical and mineralogical analyses. Chemical elements were determined by atomic absorption spectrometry, colorimetry, complexometry, and gravimetry. Organic matter was determined using the Rock-Eval 6 pyrolysis method, while the mineralogical composition was determined using a Bruker D8 ADVANCE diffractometer. The chemico-mineralogical analyses reveal that the clayey sands from Bingerville and Samo are more enriched in silica oxide (SiO2) but less enriched in iron oxide (Fe2O3). All the soils studied have a degree of laterization greater than 2, which suggests that they are non-lateritic soils. The low Total Organic Carbon (TOC) values lies between 0.1 and 0.15% by weight, which reflects the extremely low amount of organic matter in these soils. This indicates the possibility of treating these soils with hydraulic binders. The mineralogy of the studied soils denotes that they are composed of kaolinite and illite

Influence de l’âge des explants primaires sur la régénération des vitroplants de deux espèces d’ignames en côte d’ivoire: Dioscorea alata et Dioscorea cayenensis-rotundata (Dioscoreacea)

Objectif: En Côte d’Ivoire la production annuelle de Dioscorea spp est insuffisante à cause de la conservation des tubercules qui réduisent fortement les rendements des tubercule-semences. Il s’avère nécessaire de conserver tous les cultivars d’igname sous forme de vitroplant. Cette étude vise à évaluer l’effet du milieu de culture, de la désinfection et du type d’explants primaires sur la régénération et la conservation in vitro.Méthodologie et résultats: Les explants primaires prélevés sur les tiges âgées de 14, 21, 35 et 60 jours ont été désinfectés et mis en culture sur deux milieux de culture MS et MS modifié. Les explants primaires issus des tiges de 14 et 21 jours ont permis d’obtenir 99 à 100 % de vitroplants sains, 100 % de régénération au bout de 2 à 4 jours dans le milieu MS modifié avec en moyenne 3,82 à 5,14 noeuds et 1 à 2 tiges au bout de 60 jours. Tandis que ceux de 35 et 60 jours ont donné 35 à 74 %.de vitroplants sains, 1 à 4 noeuds et 1 à 2 tiges. Le milieu MS modifié et Les explants primaires issus des tiges de 14 et 21 jours permettant de régénérer les vitroplants au bout de 3 à 4 jours en moyenne ont été retenus.Conclusions et application des résultats: La conservation de toutes les variétés d’igname de la Côte d’Ivoire sous forme de vitroplants par la technique de régénération de tiges aériennes in vitro nécessite la satisfaction de certaines conditions. Ainsi pour la régénération de tous les cultivars les explants primaires prélevés sur les tiges âgées de 14 et 21 jours et le milieu de culture MS modifié ont été meilleurs. Tous les cultivars dans le milieu MS modifié ont été régénérés en moins d’une semaine et les vitroplants sains ont eu une bonne croissance offrant beaucoup de noeuds qui ont servi d’explants secondaires. La présente étude indique les  possibilités de production à grande échelle de semences des variétés d’igname pour répondre aux impératifs de sauvegarder et d’enrichir les ressources génétiques de l’igname en Côte d’Ivoire.Mots clés: Igname, explants primaires, cultivars, régénération, vitroplants, milieu de culture, âge, Côte d’IvoireEnglish Title: Influence of age to primary explants on the regeneration of vitroplant of two yam species in Côte d’Ivoire: Dioscorea alata and Dioscorea cayenensis-rotundata (Dioscoreacea)English AbstractObjectives: The annual production of Dioscorea spp in Côte d'Ivoire is insufficient because of the conservation of tubers, which greatly reduce the tuber yields. It is necessary to keep all of yam cultivars as vitroplant. This study aims to evaluate the effect of the culture medium, disinfection and type of primary explants on regeneration and in vitro conservation.Methodology and Results: Primary explants taken on older stems 14, 21, 35 and 60 days were disinfected and cultured on MS culture media and modified MS media. Primary explants from the stems of 14 and 21 days have resulted in 99 to 100% of healthy vitroplants, 100% of regeneration after 2 to 4 days in MS medium amended with an average of 3 to 5 nodes and 1 to 2 stems after 60 days. While those of 35 and 60 days gave 35-74% healthy vitroplants, from 1 to 4 nodes and 1 to 2 stems. The modified MS medium and primary explants from stems 14 and 21 days to regenerate the vitroplants after 3 to 4 days on average were selected.Conclusions and application of findings: The conservation of all varieties of yam from Côte d'Ivoire as vitroplants by aerial stems regeneration technique requires the satisfaction of certain conditions.So for the regeneration of all cultivars primary explants taken on older stems of 14 and 21 days and the modified MS culture medium were better. All cultivars in the modified MS medium were regenerated in less than a week and healthy vitroplants had good growth with many knots that served as secondary explants. This study shows the large-scale possibilities of seeds production for yam varieties to meet the requirements to safeguard and enrich the genetic resources of yams in Côte d'Ivoire.Keywords: yam, primary explants, cultivars, regeneration, vitroplants, culture medium, age, Côte d'Ivoir

Phytochimie, activité antioxydante et toxicité aiguë de plantes médicinales utilisées contre les séquelles de l’accident vasculaire cérébral en Côte d’Ivoire

Les séquelles, après un accident vasculaire cérébral, sont importantes et les patients handicapés moteurs très nombreux. La présente étude a pour objectif de définir le profil phytochimique des cinq plantes les plus utilisées pour traiter les séquelles des AVC en Côte d’Ivoire, d’évaluer leur capacité antioxydante et leur toxicité. Après le screening phytochimique, la teneur en phénols et flavonoïdes ont été quantifiés par la méthode colorimétrique de Folin-Ciocalteu. L’évaluation quantitative du potentiel antioxydant des extraits a été réalisée in vitro par le test au DPPH (1,1-diphényl-2-picryl-hydrazyle). Les tests ont mis en évidence la présence de polyphénols, de tanins et de flavonoïdes dans tous les extraits aqueux. Ces métabolites sont importants dans la prévention et le traitement des maladies cardio-vasculaires. Les taux les plus élevés de polyphénols sont présents dans les extraits aqueux d’écorce de tige de Ficus mucuso (83425,29 μg EAG/g MS) et de rameaux feuillés de Zizyphus mauritiana (74517,24 μg EAG/g MS). La plus forte teneur en flavonoïdes a été observée dans l’extrait aqueux de rameaux feuillés de Ziziphus mauritiana (20,28%). Des capacités antioxydantes importantes ont été observées dans les extraits aqueux du mélange écorces de tige/feuilles de Tamarindus indica (CI50 = 0,1269 mg/ml) et dans l’extrait d’écorce de tige de Ficus mucuso (0,1335 mg/ml). Les tests de toxicité aigüe montrent que l’extrait aqueux de l’écorce de tige de Ficus mucuso, par voie orale, à 5000 mg/kg de pc, est légèrement toxique chez les souris.Mots clés : AVC, séquelles, plantes médicinales, phytochimie, toxicité.   English Title: Phytochemistry, antioxidant activity and acute toxicity of medicinal plants used against the sequelae of stroke in Côte d’IvoireThe sequelae after a stroke are significant and there are many patients with motor disabilities. The purpose of this study is to define the phytochemical profile of the five plants most used to treat the sequelae of stroke in Côte d'Ivoire, to assess their antioxidant capacity and their toxicity. After the phytochemical screening, the content of phenols and flavonoids were quantified by the colorimetric method of Folin-Ciocalteu. The quantitative evaluation of the antioxidant potential of the extracts was carried out in vitro by the DPPH (1,1-diphenyl-2-picryl-hydrazyl) test. The tests revealed the presence of polyphenols, tannins and flavonoids in all the aqueous extracts. These metabolites are important in the prevention and treatment of cardiovascular disease. The highest levels of polyphenols are found in aqueous extracts of stem bark of Ficus mucuso (83425.29 μg EAG/ g DM) and leafy twigs of Zizyphus mauritiana (74,517.24 μg EAG / g DM). The highest content of flavonoids was observed in the aqueous extract of leafy twigs of Ziziphus mauritiana (20.28%). Significant antioxidant capacities were observed in the aqueous extracts of the stem bark / leaf mixture of Tamarindus indica (IC50 = 0.1269 mg / ml) and in the extract of the stem bark of Ficus mucuso (0.1335 mg / ml). Acute toxicity tests show that the aqueous extract of the stem bark of Ficus mucuso, taken orally, at 5000 mg / kg bw, is slightly toxic in mice.Keywords: Stroke, sequelae, medicinal plants, phytochemistry, toxicity

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Le non-respect du cadre juridique et règlementaire de la politique de décentralisation et ses conséquences sur le développement de la commune de Grand-Bassam en Cote d’Ivoire

La décentralisation a pour but de mettre en place les jalons du développement futur des villes Ivoiriennes. Débutée timidement au début des années 1980, c’est à partir des années 2000 qu’elle connaîtra un véritable essor. Cependant, après plus de trente années d’application, le carde juridique et réglementaire censé apporter une caution juridique au processus de décentralisation a du mal à s’intégrer continuellement dans les habitudes des populations. Ainsi, la décentralisation se trouve fragilisée par le non-respect des textes prescrits qui entrainent le désordre urbain, l’insalubrité et la dégradation des biens et équipements publics. La présente  tude vise à analyser le cadre d’exécution des textes juridique et règlementaire de la politique de décentralisation particulièrement dans les domaines de l’urbanisme, de l’habitat et de l’assainissement afin d’aider à améliorer la gouvernance urbaine de la commune de Grand-Bassam. Une série d’enquêtes participative auprès de la collectivité et de la direction générale de la  décentralisation et du développement local a ainsi fourni des informations relatives à la gestion de la commune dans ces divers domaines précités. La politique de désengagement de l’État en faveur du secteur privé a faiblement mis en oeuvre des moyens de contrôle des textes juridiques existants, conduisant à la prolifération des habitats ne respectant aucune règle d’urbanisme. L’absence d’une véritable politique en matière d’assainissement nuit gravement au cadre de vie des populations avec une forte répercussion sur l’espace. Mots-clés : Cadre juridique et règlementaire, décentralisation, gouvernance urbaine,Grand-Bassam English Title: The non respect of the legal and regulation frame of the decentralization policy and its consequences on the development of the municipality of Grand-Bassam The goal of decentralization is to implement the stakes of the future development of ivorian towns. It timidly started in the beginning of the 1980s and will know a real boom from the 2000s. However, after more than thirty years of application, the legaland regulation frame supposed to bring a legal guarantee to the decentralization process struggles to integrate continuously into the habits of the populations. So decentralization is weakened by the non compliance with prescribed texts, which causes urban disorder, unhealthiness, and degradation of public goods and facilities. This study aims to analyse the executing framework of legal and regulatory texts of the decentralization policy, particularly in the areas of housing, urban planning and sanitation in order to help improving the urban gouvernance of the municipality of Grand-Bassam. A set of participatory surveys to the community and the directorategeneral for decentralization and local development has provided information about management of the municipality in these various fields mentioned. The country's disagagement policy in favor of the private sector has weakly enforced the existing means of control, leading to the proliferation of the habitats that do not comply with urban planning rules. The lack of a real policy in terms of sanitation seriously harms the living environment of the populations with a strong repercussion on the space. Keywords: legal and regulatory framework, decentralization, urban governance,&nbsp

Androgenic potential and anther in vitro culture of Lagenaria siceraria (Molina) Standl and edible-seed cucurbit

Lagenaria siceraria Molina has a high productive potential of fruits but the seeds weight remain low. The aim of this study is to regenerate doubled haploids from androgenesis in order to create genotypes with good agronomic characteristics. For this purpose, flower buds of six accessions namely NI185, NI202, NI215, NI276, NI356 and NI271 were pre-treated at 4 °C for 0, 1, 2, 4, 6, 7 days. To assess the ability of these accessions to induce callus, the anthers excised from the collected floral buds were cultured following two standard protocols referred to as Metwally et al. and Kumar and Murthy, respectively. Histological sections were performed with buds of different sizes in order to select pollen at uni-nucleate stage, the most appropriate for the androgenesis. The histological sections showed that the pollen is at uni-nucleate stage when the bud size varied from 5 to 7 mm. No callus production was observed with the protocol of Metwally et al. whereas a significant formation of callus were expressed on medium corresponding to the protocol of Kumar and Murthy. The best rate (79%) of callus induction was obtained after one and two days of pre-treatment at 4 °C. The highest rate of callus induction was observed with the accessions NI271, NI276 and NI356.© 2015 International Formulae Group. All rights reserved.Keywords: Cucurbitaceae, anther culture, thermal shock, androgenesis, plant regeneratio

Propagation of Garcinia kola (Heckel) by stem and root cutting

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Effects of Seed orientation and sowing depths on Germination, Seedling vigor and yield in Oleaginous type of Bottle gourd, Lagenaria siceraria (Molina Standl)

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