Etude Comparative de Deux Garnitures (Noix de Pain de Singe et de Jujube) Dans une Colonne Garnie: Hydrodynamique et Transfert de Matière

Pour bien comprendre l’efficacité de transfert de matière dans les biofiltres, les paramètres hydrodynamiques et de transfert de matière ont été étudiés pour deux garnitures différentes (noix de pain de singe et de jujube) dans un réacteur triphasé à lit fixe fonctionnant à co-courant gaz-liquide. Dans le cadre de ce travail, après la caractérisation des graines une étude d’hydrodynamique et de transfert de matière de l’oxygène a été faite. Les expériences ont été réalisées au sein d’une colonne en verre cylindrique de 0,1 m de diamètre et 1,5 m de hauteur. Cette dernière a été remplie avec des noix de pain de singe ou de jujube comme matériaux de garnissage. Les résultats obtenus ont montré que les pertes d’énergie ou la chute de pression (P) est 3,1875 cmCE contre 0,725 cmCE en moyenne respectivement pour le pain de singe et le jujube, la rétention liquide dynamique (εLD) est 0,223 contre 0,348 en moyenne respectivement pour le pain de singe et le jujube ainsi que la capacité d’oxygénation (CO) est 70,282 g.m-3 .h-1 contre 163,674 g.m-3 .h-1 en moyenne respectivement pour le pain de singe et le jujube. Au vue de ces résultats, les noix de jujube présentent sur tous les plans, les meilleures caractéristiques pour être utilisés comme matériaux de garnissage en vue des études pilotes ultérieures. To fully understand the mass transfer efficiency in biofilters, hydrodynamics and mass transfer parameters were investigated for two different fillings (monkey bread and jujube) in a three-phase fixed-bed reactor operating at co-flow gas-liquid. As part of this work, after the characterization of seeds a hydrodynamic study and transfer of oxygen mass were made. The experiments were carried out in a cylindrical glass column 0.1 m in diameter and 1.5 m in height. The latter wasfilled with monkey bread or jujube as filling materials. The results obtained showed that the energy losses or the pressure drop (P) is 3.11875 cmCE against 0.725 cmCE on average respectively for monkey bread and jujube, the dynamic liquid retention (εLD) is 0.223 against 0.348 on average respectively for monkey bread and jujube and the oxygenation capacity (OC) is 70.282 gm-3 .h-1 against 163.674 gm-3 .h-1 on average respectively for monkey bread and jujube. As a result, jujube nuts have the best characteristics on all levels for use as packing materials for pilot studies

Assessment of the Effect of Different Varieties of Tomato and Hot Pepper on Nematodes Attack in Senegal

Tomato and hot pepper are very susceptible to nematodes. The Parasitic Plant Nematodes (PPN) are controlled using chemicals or resistant varieties. This study focuses on appraising the resistance levels of local and American varieties through the plant characteristics (growth, biomass) and the nematodes metrics (gall index, population). For each crop, three American varieties were tested to ascertain their resistance to the nematodes in Senegal using the following plant materials and protocol. American tomatoe varieties are as follows: Small Fry, Jet Setter, and Celebrity. The hot pepper American varieties include Charleston Bell, Carolina Cayenne, and Carolina Wonder. All of these were provided by the Entomology and Nematology Department and Cooperative Extension Service at the University of Florida. They were compared with highly susceptible Senegalese local varieties which were Roma and Orbit for tomato and Safi for hot pepper. The test was conducted in pots containing sterilized sand of dune and placed in a shelter in a completely randomized design. There were 200 second stage juveniles (J2) of Meloidogyne inoculated in each pot thirteen days after transplantation. After fifty days, plants were uprooted to collect agronomic and nematological parameters. Results for tomato showed, in general, better growth from Roma than the other American tomato varieties. Celebrity offered possibilities of reducing Meloidogyne population, while Small Fry and Jet Setter’s growth were not affected by Meloidogyne populations. Safi, which is the local hot pepper variety, displayed the poorest growth. Carolina Cayenne variety also performed better than Safi in heavy infestations. Analysis of Meloidogyne J2 final population data (in the soil and root) showed a significant difference between Small Fry and Celebrity for tomato. As for hot pepper, Carolina Cayenne performed significantly better than Carolina wonder and Safi. This opens up further research opportunities on the impact of Meloidogyne nematode genus and the agronomic parameters

High level of treatment failure and drug resistance to first-line antiretroviral therapies among HIV-infected children receiving decentralized care in Senegal

Abstract Background In Senegal in 2015, an estimated 4800 children were living with HIV, with 1200 receiving ARV treatment, of whom half had follow-up care in decentralized sites outside Dakar. However, until now no studies have determined the efficacy of pediatric treatment in decentralized settings, even though the emergence of viral resistance, particularly among children in Africa, is a well-known phenomenon. This study aimed to assess the virological status of HIV-infected children in all decentralized facilities to help improve access to quality care. Methods A cross-sectional epidemiological and virological study was conducted in all of Senegal’s regions, except Dakar, between March and June 2015 and sought to include all HIV-infected children and adolescents (0–19 years), treated or not with ARVs. Socio-demographic and clinical data and a blood sample on blotting paper were collected for children from treatment sites. Samples were routed on public transportation, assisted by a network of community health workers. A viral load (VL) assay was performed for each child, followed by genotyping when it exceeded 1000 copies/mL (3 log10). Results Of the 851 identified children, 666 (78%) were enrolled in the study. Half of the children were girls, and the average age was 8 years (6 months–19 years). Most of the children (96.7%) were infected with HIV-1, and 90% were treated with ART, primarily with AZT + 3TC + NVP/EFV therapeutic regimen. The median duration of time on ART was 21 months (1–129). VL was measured for 2% of children before this study. Almost two-thirds (64%) of the children are experiencing virological failure. Among them, there was resistance to at least one drug for 86.5% of cases. Also, 25% children presented resistance to one drug and 40% to two out of three. For nearly one-third of the children presenting resistance, none of the three drugs of the treatment was active. Factors associated with virological failure were male sex, follow-up by a generalist rather than a specialist, and treatment interruptions. Conclusions We observed a high level of virological failure and a high percentage of viral resistance among children receiving health care in decentralized facilities in Senegal