555 research outputs found

    Évaluation de la sensibilitĂ© de sept clones de palmier Ă  huile (Elaeis guineensis Jacq.) Ă  Coelaenomenodera lameensis Berti et Mariau (Coleoptera, Chrysomelidae) Konan J.

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    Objectifs : Évaluer la sensibilitĂ© de 7 clones d’Elaeis guineensis Ă  Coelaenomenodera lameensis (Coleoptera : Hispinae) et estimer les dĂ©gĂąts occasionnĂ©s par l’insecte au terme d’un cycle de dĂ©veloppement complet sur chaque type de matĂ©riel clonal.MĂ©thodologies et RĂ©sultats : des insectes adultes de C. lameensis ont Ă©tĂ© transposĂ©s sur des folioles de clones d’Elaeis guineensis isolĂ©s dans des manchons. L’évolution des insectes a Ă©tĂ© ensuite observĂ©e à chaque Ă©tape du cycle normal de dĂ©veloppement de C. lameensis. Les dĂ©gĂąts provoquĂ©s par l’insecte ont étĂ© estimĂ©s par le rapport entre la surface de foliole attaquĂ©e et la surface totale de foliole. Les rĂ©sultats ont montrĂ© que certains clones Ă©taient moins favorables au dĂ©veloppement de l’insecte que d’autres. Le clone LMC247, avec 53,80 % ± 2,56 de surface foliaire attaquĂ©e, a Ă©tĂ© plus sensible Ă  l’insecte que les autres clones LMC159, LMC161, LMC022, LMC010, LMC270 et LMC291 oĂč les dĂ©gĂąts observĂ©s ont Ă©té en dessous de 25%..Conclusion et Application : au regard des rĂ©sultats, il ressort que le dĂ©veloppement de C. lameensis est influencĂ© par le type de matĂ©riel clonal. Les dĂ©gĂąts sur les clones testĂ©s ont Ă©tĂ© gĂ©nĂ©ralement de faible intensitĂ©. Cette approche expĂ©rimentale, laisse prĂ©sager de bonnes perspectives pour la lutte gĂ©nĂ©tique contre C. lameensis.. En effet, plus de 300 clones de palmier ont dĂ©jĂ  Ă©tĂ© crĂ©es en CĂŽte d’Ivoire. Un criblage Ă©largi Ă  l’ensemble de ce matĂ©riel va permettre d’identifier Ă  terme des clones performants pour contrĂŽler le ravageur, au regard de l’homogĂ©nĂ©itĂ© de ce type de matĂ©riel vĂ©gĂ©tal.Mots clĂ©s : clone, palmier Ă  huile, lutte gĂ©nĂ©tique, CoelĂŠnomenodera lameensisEvaluation of seven oil palm clones (Elaeis guineensis Jacq.) sensibility to Coelaenomenodera lameensis Berti and Mariau (Coleoptera, Chrysomelidae)Objective: this study aims to evaluate seven oil palm clones sensibility to Coelaenomenodera lameensis (Coleoptera: Hispinae) and to estimate the damage caused by this insect on each type of clonal material.Methods and results: adult insects of C. lameensis were transposed on Elaeis guineensis clones leaflets isolated in canvas bags. Insect evolution was observed at each stage of normal development cycle of C. lameensis. The damage caused by the insect was estimated using the ratio of the surface of leaflet attacked and the total surface of leaflet. The results showed that some clones were less favorable to the development of C. lameensis than others. The clone LMC247, with 53.80 ± 2.56% of leaf surface attacked was more susceptible to C. lameensis than the other clones LMC159, LMC161, LMC022, LMC010, LMC270 and LMC291. For these clones, the damages noted were below 25% of leaf area attacked.Conclusion and application: the results showed that C. lameensis development depended of the clones. Overall, a low intensity of damage was observed on the leaflet of the clones. This experimental approach suggests good projection for genetic control of C. lameensis with oil palm clone material. Indeed, more than 300 oil palm clones have already been established in CĂŽte d'Ivoire. The screening of this material can help selecting performing material to control the pest due to the homogeneity of this type of plant material. Key words: clone, oil palm, genetic control, CoelĂŠnomenodera lameensi

    Evaluation de l’efficacite de quatre formulations de chlorpyriphos ethyl contre la cochenille Farineuse du manguier Rastrococcus invadens Williams (Homoptera : Pseudococcidae) : bilan de dix annees d’experimentation en Cîte D’Ivoire

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    La cochenille farineuse du manguier, Rastrococcus invadens (Homoptera : Pseudococcidae) est l’un des principaux ravageurs du manguier en CĂŽte d’Ivoire, particuliĂšrement dans la rĂ©gion nord qui fournit les mangues exportĂ©es. En attendant la mise en place de la lutte biologique envisagĂ©e, et devant l’ampleur des dĂ©gĂąts pouvant favoriser des traitements abusifs de la part des producteurs, des expĂ©rimentations ont Ă©tĂ© initiĂ©es pour sĂ©lectionner des insecticides efficaces en vue de leur homologation. Sur station de recherche, le premier screening a concernĂ© 8 formulations d’insecticides appliquĂ©es Ă  doses fortes (2 litres / ha) sur 100 mÂČ de parcelle Ă©lĂ©mentaire de manguiers. Ensuite, pour chaque formulation retenue, trois doses ont Ă©tĂ© testĂ©es (2 litres / ha, 1 litre / ha et 0,5 litre / ha) sur 200 mÂČ. En milieu paysan, la dose optimale a Ă©tĂ© confirmĂ©e sur au moins 20 ha dans des essais couples. Le screening prĂ©liminaire a mis en Ă©vidence l’efficacitĂ© des formulations Ă  base de chlorpyrifos Ă©thyl avec une rĂ©manence de 4 semaines. L’évaluation de 3 doses de ces formulations en station a permis de retenir la dose efficace de 1 litre / ha soit 480 g dechlorpyrifos-Ă©thyl / ha. Les tests rĂ©alisĂ©s en milieu paysan ont confirmĂ© l’efficacitĂ© des 4 formulations de chlorpyrifos-Ă©thyl contre le ravageur : Dursban 4 E, Cyren 480 EC, Pyriforce 480 EC et Pyrical 480 EC. L’exĂ©cution raisonnĂ©e des traitements permet Ă  la lutte chimique de s’intĂ©grer harmonieusement dans un programme de gestion intĂ©grĂ©e de la cochenille farineuse.Mots clĂ©s : Rastrococcus invadens, cochenille farineuse du manguier, lutte chimique, chlorpyrifos-Ă©thyl.EVALUATION OF FOUR FORMULATIONS OF CHLORPYRIPHOS ETHYL AGAINST THE MANGO MEALY BUG Rastrococcus invadensWILLIAMS  (HOMOPTERA : PSEUDOCOCCIDAE) : ASSESSMENTOF TEN YEARS  EXPERIMENTATION IN CÔTE D’IVOIREThe mango mealy bug, Rastrococcus invadens (Homoptera,  Pseudococcidae) is one of the main pests of mango in CĂŽte d’Ivoire,  particularly in the northern region that provides the exported mangoes. Before the using of biological control considered, and faced with the extent of damages that may promote abusive treatment by the producers,  experiments were initiated to select effective insecticides for their approval. On research station, the first screening has involved eight formulations of insecticides applied at high doses (2 L / ha) of 100 mÂČ plot of mango trees. Then, for each formulation selected, three doses were tested (2 liters / ha, 1 liter / ha and 0.5 l / ha) on 200 mÂČ. On-farm, the optimal dose was confirmed at least 20 ha in trials couples. The preliminary  screening has shown the effectiveness of formulations containing  chlorpyrifos ethyl with a remanence of 4 weeks. The evaluation of three  doses of these formulations on station allowed to retain the effective dose of 1 l / ha or 480 g of chlorpyrifos-ethyl / ha. The on-farm tests have  confirmed the effectiveness of four formulations of chlorpyrifos-ethyl against the pest: Dursban 4 E, Cyren 480 EC, Pyriforce 480 EC and Pyrical 480 EC. The rational treatment allows to chemical control to integrate  seamlessly into an integrated management program against the mealy  bug.Key words : Rastrococcus invadens, mango mealy bug, chemical control, chlorpyrifos ethyl

    Characteristics of Si-Solar Cell (PV) Waveguide Structure Using Transfer Matrix Method

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    In this work, the characteristics of a Si-solar cell (PV) model is studied. The proposed model is a four layer system with an ultra-thin film of Fe-InGaAsPlaid above Silicon (Si) substrate and covered by AlON layer that is exposed to air directly. The efficiency is measured by the reflectance power (R) and transmittance power (T). R and T are derived by using the transfer matrix method for both TE and TM modes. The total reflectance (Ravg) and the total transmittance (Tavg) are taken as the average value for the TE and TM modes. Ravg and Tavg are plotted versus the wavelength at different values for AlON layer thickness l1 and Fe-InGaAsP layer thickness l2 using Maple. The result shows that the minimum value of Ravg is shifted toward higher wavelengths with increasing l1. The minimum of Ravg is almost zero while the rest of the spectrum is less than 0.25% which is lower than any previous results. We also noticed

    Prophylactic effect of artemether on human Schistosomiasis mansoni among Egyptian children : a randomized controlled trial

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    A double-blind, randomized controlled trial was conducted in an endemic focus for Schistosoma mansoni in Kafr El-Sheikh Governorate, Northern Nile Delta, Egypt, to evaluate the prophylactic effect of artemether (ART) given in conjunction with praziquantel (PZQ). The study encompassed 913 primary school children randomly assigned to two treatment groups PZQ/ART and PZQ/ART-placebo. At baseline, both groups received 40mg/kg body weight of PZQ twice four weeks apart, after which one group received 6mg/kg body weight of ART every 3 weeks in 5 cycles during the transmission season and the other group received ART-placebo. At the end of the study, prevalence of infection among the PZQ/ART was approximately half that of the PZQ/ART-placebo group, i.e. 6.7% versus 11.6%, and incidence of new infections for the PZQ/ART was 2.7% versus 6.5% for the PZQ/ART-placebo. In conclusion, PZQ/ART combined therapy might be considered as an adjunct measure against human schistosomiasis, by specifically reducing transmission and therefore contribute to disease elimination

    PiĂ©geage des Mouches des Fruits (Diptera : Tephritidae) À Base D’extraits de Ocimum Basilicum L. (Lamiaceae) : Cas de Bactrocera Dorsalis, Principal Ravageur de Mangues en CĂŽte d’Ivoire

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    Les cultures fruitiĂšres, en particulier la mangue en CĂŽte d’Ivoire, sont sous la menace des mouches des fruits. Les dĂ©gĂąts se sont accrus avec l’invasion de Bactrocera dorsalis. En outre, la baisse des pertes en vergers de manguiers exige l’utilisation du mĂ©thyl eugĂ©nol pour sa dĂ©tection et le suivi du monitoring de sa population. Malheureusement, les attractifs sexuels spĂ©cifiques de mouchessont inaccessibles aux producteurs de la CĂŽte d’Ivoire. L’objectif de cette Ă©tude est d’évaluer l’efficacitĂ© de Ocimum basilicum dans de la capture de B. dorsalis. Ces trois formulations du basilic (feuilles fraĂźches malaxĂ©es, poudre de basilic et macĂ©rĂąt du basilic) et le mĂ©thyl eugĂ©nol sont utilisĂ©es en piĂ©geage dans les vergers de manguiers Ă  Korhogo. Les piĂšges ont Ă©tĂ© relevĂ©s chaque semaine et chaque jour respectivement pour le MĂ©thyl eugĂ©nol et les formulations du basilic. Les formulations ont permis de capturer une importante population de B. dorsalis (99,41 %) avec une prĂ©valence (FTD) moyenne journaliĂšre de 10,141 individus/jour/piĂšge et d’autres espĂšces de mouches de fruits. La poudre de basilic montre une rĂ©manence plus longue (28,67 ± 18,17 jours) tandis que le macĂ©rĂąt de basilic montre une capture hebdomadaire plus Ă©levĂ©e (513,4 ± 72,34 individus). Les captures moyennes les plus Ă©levĂ©es ont Ă©tĂ© observĂ©es avec le MacĂ©rĂąt de basilic (4419 ± 1090 individus) et le MĂ©thyl eugĂ©nol (4899,67 ± 1511,74 individus). Le macĂ©rĂąt de feuilles fraĂźches de basilic et la poudre de feuilles sĂšches de basilic peuvent ĂȘtre recommandĂ©es auprĂšs des producteurs de mangues dans la lutte contre B. dorsalis. Fruit crops, especially mangoes in CĂŽte d'Ivoire are threatened by the fruit flies. The damage has increased with the invasion of Bactrocera dorsalis. In addition, the decline in mango orchard losses requires the use of methyl eugenol for the detection and monitoring of Bactrocera population. Unfortunately, the sex-specific attractants of flies are inaccessible to producers in CĂŽte d'Ivoire. The aims of this study is to evaluate the efficacy of Ocimum basilicum in the capture of B. dorsalis. Three basil formulations (fresh mixed leaves, basil powder and basil macerate) and methyl eugenol are used for trapping in mango orchards in Korhogo. The captured insects were collected weekly and daily for methyl eugenol and basil formulations respectively. The formulations captured a large population of B. dorsalis (99.41%) with an average daily prevalence (FTD) of 10,141 individuals / day / trap and other fruit fly species. Basil powder has the longest persistence (28.67 ± 18.17 days) and basil macerate has the highest weekly catch (513.4 ± 72.34 individuals). The highest average catches were observed with basil macerate (4419 ± 1090 individuals) and methyl eugenol (4899.67 ± 1511.74 individuals). Fresh basil leaf macerate and dry basil leaf powder may be recommended to mango growers in the control of B. dorsalis

    Damage index in childhood-onset systemic lupus erythematosus in Egypt

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    <p>Abstract</p> <p>Background</p> <p>To investigate the prevalence of cumulative organ damage among Egyptian children with juvenile-onset systemic lupus erythematosus (jSLE) and the relationships between the organ damage and the demographic data, clinical variables, and disease activity.</p> <p>Methods</p> <p>A total of 148 patients with jSLE have been followed in the pediatric rheumatology clinic and section at Cairo University. These patients were evaluated by retrospective chart review. The organ system damage due to SLE was measured using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). Risk factors for damage were also studied including demographic criteria as well as clinical and laboratory manifestations.</p> <p>Results</p> <p>Overall, 43.9% of the patients had damage within a mean of 6.57 ± 3.59 years of disease diagnosis. Neuropsychiatric (NPS-21%) and renal (16.9%) system involvement were observed most frequently, followed by cardiovascular (11.5%), skin (9.5%), pulmonary (6.1%), and ocular (4.8%), with a mean SDI score of 0.93 ± 1.37. In our study, the presence of neuropsychiatric manifestations at diagnosis showed the strongest association with the presence of later disease damage.</p> <p>The number of SLE diagnostic criteria at presentation was strongly associated with the total SDI score, and the renal damage was significantly more prevalent in patients with age at disease diagnosis below 10 years of age. A higher mean disease duration was found in patients with musculoskeletal damage.</p> <p>Conclusion</p> <p>We found that cumulative organ damage, as measured by the SDI, was present in 43.9% of Egyptian patients with juvenile-onset SLE. The damage was significantly more likely in patients who had more SLE diagnostic criteria at time of disease presentation and NPS manifestations at the time of diagnosis.</p

    Synthesis, Characterization of Poly Heterocyclic Compounds, and Effect on Cancer Cell (Hep-2) In vitro.

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    A synthesis series of new heterocyclic derivatives (A2-A7) (pyrrole, pyridazine, oxazine and imidazol) derived from 4-acetyl-2,5-dichloro-1-(3,5-dinitrophenyl)-1H-pyrrole-3-carboxylate(A1) have been synthesised. Synthesis of compound (A2) by the reaction of starting material (A1) with hydroxyl amine hydrochloride in the presence of pyridine. Compound (A2) was reacted with hydrazine hydrate in dry benzene to give (A3) derivative. The compound )A3( deals with sodium nitrite to give diazonium salt, and the reaction diazonium salt with ethyl acetoacetate to produce compound (A4). To a mixture of compound (A4) and hydroxyl amine with sttired to yield (A5).Compound (A6) was prepared by reaction compound (A4) with thiosemicarbazide in presence of drops of acetic acid. Synthesis of 1compound (A7) by reaction compound (A6) with ethyl chloro acetate. The reactions have been monitored by TLC and the synthesized compounds were characterized using spectrophotometric methods FT-IR, 1H NMR.The biological effects of the prepared compounds on the cancer cells were studied in vitro. The results indicated that these Synthesized compounds (A1–A7) inhibited1 the cancer1 cells1 efficiently, the compound (A6) was activity inhibited on the cancer cells

    Essai de lutte contre oryctes monoceros olivier (coleoptera : dynastidae) par l’utilisation de l’acide 4-mĂ©thyloctanoĂŻque en cĂŽte -d’ivoire

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    (Arecaceae), en CĂŽte d’Ivoire. Pour lutter contre ce ravageur, l’acide 4-methyloctanoĂŻque a Ă©tĂ© initiĂ©. Au cours de ces travaux, 3 types de diffuseurs (Da, Db, Dc) contenant les diffĂ©rentes doses ont Ă©tĂ© expĂ©rimentĂ©s. L’étude a Ă©tĂ© menĂ©e sur 9 mois repartie sur 4 phases dont 1 mois sans diffuseurs, 4 mois avec diffuseurs, 2 mois retrait desdiffuseurs et 2 mois post diffuseurs. Les visites des cocotiers ont Ă©tĂ© effectuĂ©es 3 fois par semaine avec extraction des insectes des galeries en notant les caractĂ©ristiques climatiques et le sexe des insectes. Les diffuseurs ont Ă©tĂ© pesĂ©s au dĂ©but et chaque mois pendant la phase avec diffuseurs. On note que les trois types de diffuseurs ont la mĂȘme efficacitĂ© contre les attaques de O. monoceros mais le diffuseur Dc, caractĂ©risĂ© par la dose faible, est Ă©conomiquement plus avantageux et pourrait ĂȘtre vulgarisĂ© auprĂšs des paysans, pour la protection de leurs plantations.Mots clĂ©s : Cocos nucifera, Oryctes monoceros, Diffuseurs, Acide 4-mĂ©thyloctanoĂŻqueOryctes monoceros Olivier is one of the most dangerous pests of young coconuts Cocos nucifera Linne (Arecaceae) in CĂŽte-d’Ivoire. In order to reduce their populations, 4-methyloctanoĂŻc acid was initiated. In this work, 3 different types of diffusers (Da, Db, Dc) was tested. The study over nine months covered four phases with one month (without diffusers), four month (with diffusers), two month (diffuser withdrawal) and two month (post diffuser). Coconuts were visited 3 twice in a week by collecting insects of galleries and wrote down climatic characteristics, sex of insects. Diffusers were weighted at the beginning and every month during phase with diffusers. We notice that three types of diffusers have the same effectiveness against O. monoceros attacks, diffuser Dc, characterized by a low concentration, is economically more reasonable and could be recommended to the farmer for the protection of their plantations

    Uptake of Fluoride from Water Using Recycled Raw Beef Bone as an Environmently Freindly Waste

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    Excessive intake of fluoride, mainly through drinking water is a serious health hazard affecting humans worldwide. In this study, the defluoridation capacities of locally available raw waste beef bones have been estimated. Several experimental parameters including contact time, pH, bone dose, fluoride initial concentration, bone grains size, agitation rate, and the effect of co-existence of anions in actual samples of wastewater were studied for fluoride removal from aqueous solutions. Results indicated excellent fluoride removal effeciency up to 99.7% at fluoride initial concentration of 10 mg F/L and 120 min contact time. Maximum fluoride uptake was obtained at neutral pH range 6-7. Fluoride removal kinetic was well described by the pseudo-second order kinetic model. Both, Langmuir and Freundlich isotherm models could fit the experimental data well with correlation coefficient values > 0.99 suggesting favorable conditions of the process. Furthermore, it was found that the co-existing anions had no significant effect on fluoride removal. Ion exchange and fluoride precipitation are the modes of fluoride removal

    Effect of taurine supplementation on hyperhomocysteinemia and markers of oxidative stress in high fructose diet induced insulin resistance

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    <p>Abstract</p> <p>Background</p> <p>High intake of dietary fructose is accused of being responsible for the development of the insulin resistance (IR) syndrome. Concern has arisen because of the realization that fructose, at elevated concentrations, can promote metabolic changes that are potentially deleterious. Among these changes is IR which manifests as a decreased biological response to normal levels of plasma insulin.</p> <p>Methods</p> <p>Oral glucose tolerance tests (OGTT) were carried out, homeostasis model assessment of insulin resistance (HOMA) was calculated, homocysteine (Hcy), lipid concentrations and markers of oxidative stress were measured in male <it>Wistar </it>rats weighing 170-190 g. The rats were divided into four groups, kept on either control diet or high fructose diet (HFD), and simultaneously supplemented with 300 mg/kg/day taurine via intra-peritoneal (i.p.) route for 35 days.</p> <p>Results</p> <p>Fructose-fed rats showed significantly impaired glucose tolerance, impaired insulin sensitivity, hypertriglyceridemia, hypercholesterolemia, hyperhomocysteinemia (HHcy), lower total antioxidant capacity (TAC), lower paraoxonase (PON) activity, and higher nitric oxide metabolites (NOx) concentration, when compared to rats fed on control diet. Supplementing the fructose-fed rats with taurine has ameliorated the rise in HOMA by 56%, triglycerides (TGs) by 22.5%, total cholesterol (T-Chol) by 11%, and low density lipoprotein cholesterol (LDL-C) by 21.4%. Taurine also abolished any significant difference of TAC, PON activity and NOx concentration among treated and control groups. TAC positively correlated with PON in both rats fed on the HFD and those received taurine in addition to the HFD. Fructose-fed rats showed 34.7% increase in Hcy level. Taurine administration failed to prevent the observed HHcy in the current dosage and duration.</p> <p>Conclusion</p> <p>Our results indicate that HFD could induce IR which could further result in metabolic syndrome (MS), and that taurine has a protective role against the metabolic abnormalities induced by this diet model except for HHcy.</p
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