816 research outputs found

    Translated Poisson approximation to equilibrium distributions of Markov population processes

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    The paper is concerned with the equilibrium distributions of continuous-time density dependent Markov processes on the integers. These distributions are known typically to be approximately normal, and the approximation error, as measured in Kolmogorov distance, is of the smallest order that is compatible with their having integer support. Here, an approximation in the much stronger total variation norm is established, without any loss in the asymptotic order of accuracy; the approximating distribution is a translated Poisson distribution having the same variance and (almost) the same mean. Our arguments are based on the Stein-Chen method and Dynkin's formula.Comment: 18 page

    Agronomic potential value of household urban solid wastes by composting and composts quality assessment

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    Using composting technology, the biodegradable fraction of solid wastes collected from Agbalepedogan district in Lomé (Togo) was transformed into composts with no phytotoxicity suitable for use in agriculture. The household urban solid wastes were mixed with poultry manure and Mucuna pruriens leaves in appropriate percentages and transformed into composts. The composting process was monitored by temperature, pH and C/N ratio controlling. The composts quality was appreciated by phytotoxicity test, particle size distribution, contents of nitrogen, phosphorus, potassium, organic matter and trace elements. The results showed that composts particle size distribution presented four fractions (>10 mm, 5-10 mm, 2-5 mm and ≤2 mm) whose average percentages are respectively 9.04±0.2%; 10.71±0.2%; 12.68±0.4% and 67.53±0.6%, respectively. Composts produced contained 1.02±0.1% - 2.72±0.2% of nitrogen, 1.35±0.3% - 2.70±0.4% of phosphorus, 1.31±0.2% - 1.72±0.3% of potassium and 23.50±0.4% - 37.75±0.5% of organic matter. The pH in final composts were between 8.50±0.2 and 9.00±0.3 while C/N ratio varying from 8.06±0.2 to 13.13±0.2. The concentrations of some heavy metals in final products were 79.8±1.7 - 140.2±1.6 mg/kg.dm of zinc, 27.1±1.01 - 76.6±1.03 mg/kg.dm of copper, 2.07±0.33 - 9.19±0.22 mg/kg.dm of lead, 4.13±0.16 - 11.05±0.36 mg/kg.dm of nickel and 0.79±0.02 - 2.15±0.03 mg/kg.dm of cadmium. These concentrations were lower than the limited value for heavy metals prescribed by French and US EPA regulation for organic and organic-mineral fertilizers. Int. J. Agril. Res. Innov. Tech. 9(2): 1-8, December 201

    A Solution for Little Hierarchy Problem and b --> s gamma

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    We show that all the parameters which destabilize the weak scale can be taken around the weak scale in the MSSM without conflicting with the SM Higgs mass bound set by LEP experiment. The essential point is that if the lightest CP-even Higgs h in the MSSM has only a small coupling to Z boson, g_{ZZh}, LEP cannot generate the Higgs sufficiently. In the scenario, the SM Higgs mass bound constrains the mass of the heaviest CP-even Higgs H which has the SM like g_{ZZH} coupling. However, it is easier to make the heaviest Higgs heavy by the effect of off-diagonal elements of the mass matrix of the CP-even Higgs because the larger eigenvalue of 2 times 2 matrix becomes larger by introducing off-diagonal elements. Thus, the smaller stop masses can be consistent with the LEP constraints. Moreover, the two excesses observed at LEP Higgs search can naturally be explained as the signals of the MSSM Higgs h and H in this scenario. One of the most interesting results in the scenario is that all the Higgs in the MSSM have the weak scale masses. For example, the charged Higgs mass should be around 130 GeV. This looks inconsistent with the lower bound obtained by the b --> s gamma process as m_{H^\pm}>350GeV. However, we show that the amplitude induced by the charged Higgs can naturally be compensated by that of the chargino if we take the mass parameters by which the little hierarchy problem can be solved. The point is that the both amplitudes have the same order of magnitudes when all the fields in the both loops have the same order of masses.Comment: 14 pages, 5 figures, input parameter slightly changed, figures replaced, references correcte

    Primary Klebsiella pneumoniae Liver Abscess with Metastatic Spread to Lung and Eye, a North-European Case Report of an Emerging Syndrome

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    A syndrome of community acquired liver abscess caused by highly virulent hypermucoviscous, rmpA positive Klebsiella pneumoniae strains occurs with high incidence in Asia. We here report a case complicated by metastatic infection, to our knowledge, the first one described in Northern Europe. This and other recently reported cases indicate the emergence of this severe syndrome outside of Asia

    Evaluation du potentiel insecticide de l’huile essentielle de Ocimum canum Sims sur Aphis gossypii Glover (Homoptera : Aphididae) au Togo

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    Afin de contribuer à l’élaboration d’une stratégie de gestion intégrée des ravageurs associés à la culture cotonnière, le potentiel insecticide de l’huile essentielle de Ocimum canum et de son composé majoritaire le terpinéol-4 a été évalué sur les adultes d’Aphis gossypii, puceron du cotonnier. Les tests biologiques ont été effectués en laboratoire selon la méthodologie Insecticide Resistance Action Commitee (IRAC) N° 1 Version 2. Les résultats de ces tests ont révélé que l’huile essentielle de O. canum et le terpinéol-4 possèdent de remarquables propriétés aphicides. Ils ont induit 100% de mortalité des pucerons adultes à la concentration minimale de 4 μl.ml-¹. Les DL50 mesurées ont indiqué les valeurs de 1,49 μl.ml-¹ et 2,06 μl.ml-¹ respectivement pour l’huile essentielle et le terpinéol-4. Les essais au champ seront nécessaires pour confirmer l’intérêt pratique de ces résultats dans l’élaboration d’un pesticide naturel contre ce puceron.Keywords: Cotonnier, terpinéol-4, puceron du cotonnier, bio pesticides, propriétés aphicide

    Efficacite des bioinsecticides a base de l’huile essentielle de Cymbopogon schoenanthus (L.) spreng contre les punaises rouges (Dysdercus voelkeri, schmidt) en culture cotonniere au Togo

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    De nos jours la lutte contre les punaises rouges, ravageurs du cotonnier, se résume en l’utilisation d’insecticides chimiques de synthèse. Nombre de ces produits utilisés sont persistants et leur grande toxicité sur la santé humaine et environnementale est préoccupante. Dans la recherche d’alternatives aux insecticides chimiques de synthèse, ce présent travail de recherche vise à évaluer le potentiel insecticide des émulsions aqueuses à base de l’huile essentielle de Cymbopogon schoenanthus (L.) contre Dysdercus voelkeri, un des redoutables ravageurs du cotonnier au Togo. Des émulsions aqueuses à différentes concentrations ont été utilisées dans les traitements phytosanitaires sur culture cotonnière en comparaison avec des insecticides binaires vulgarisés (lambdacyhalothrine/profénofos 15/300 gha-1 et cyperméthrine/acétamipride 36/8 gha-1). Les dénombrements de D. voelkeri sur les plantes cibles de chaque parcelle élémentaire ont montré que la dose la plus forte de l’émulsion (6%) et le témoin positif (insecticide vulgarisé) ont été plus efficaces avec des densités de populations faibles de punaises respectivement de 7,14 ± 1,46 et 4,86 ± 1,84 punaises/plant. Contrairement les autres doses (4 et 2%) d’émulsions à base de l’huile essentielle de C. schoenanthus ont eu dans leurs parcelles respectivement 39,57±5,81 et 45,28±3,92 punaises/plant et le témoin (55,71 ± 5,23 punaises/plant). L’analyse sanitaire des jeunes capsules tombées sous les cotonniers a révélé que la dose la plus forte de l’émulsion (6%) et le témoin positif ont réduit respectivement les piqûres des punaises de 71,40 et 72,33% par rapport au témoin. Les taux de réduction des piqûres dans les parcelles à traitements de 4 et 2% de l’émulsion ont été faibles avec des taux respectifs de 55,32% et 22,83%. Ces résultats révèlent clairement que l’émulsion aqueuse formulée et testée dans l’étude peut réduire significativement les attaques de ces ravageurs. Cette étude montre la possibilité de l'utilisation de l’huile essentielle de C.schoenanthus comme matière première dans la formulation de biopesticide comme alternative aux insecticides chimiques de synthèse dans la lutte contre les punaises rouges du cotonnier au Togo

    Gestational Diabetes Triggers Postpartum Cardiac Hypertrophy via Activation of Calcineurin/NFAT Signaling

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    Population-based studies identified an association between a prior pregnancy complicated by gestational diabetes mellitus (GDM) and cardiac hypertrophy and dysfunction later in life. It is however unclear whether GDM initiates this phenotype and what are the underlying mechanisms. We addressed these questions by using female rats that express human amylin (HIP rats) as a GDM model and their wild-type (WT) littermates as the normal pregnancy model. Pregnant and two months postpartum HIP females had increased left-ventricular mass and wall thickness compared to non-pregnant HIP females, which indicates the presence of concentric hypertrophy. These parameters were unchanged in WT females during both pregnancy and postpartum periods. Hypertrophic Ca2+-dependent calcineurin/NFAT signaling was stimulated two months after giving birth in HIP females but not in the WT. In contrast, the CaMKII/HDAC hypertrophy pathway was active immediately after giving birth and returned to the baseline by two months postpartum in both WT and HIP females. Myocytes from two months postpartum HIP females exhibited slower Ca2+ transient relaxation and higher diastolic Ca2+ levels, which may explain calcineurin activation. No such effects occurred in the WT. These results suggest that a GDM-complicated pregnancy accelerates the development of pathological cardiac remodeling likely through activation of calcineurin/NFAT signaling
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