Caracterisation agro-morphologique des accessions de fonio (Digitaria exilis) collectees au nord de la Cote d’Ivoire

Le fonio [Digitaria exilis Stapf (Kippist.)], céréale à petits grains, cultivée et consommée dans le nord de la Côte d’Ivoire, est un aliment clé de la  sécurité alimentaire des populations de cette zone. Cependant, aucune étude portant sur la diversité génétique des variétés locale n’a été réalisée à ce jour. La présente étude vise à évaluer le niveau et la structuration de la variabilité agro-morphologique. Ainsi, 217 accessions de fonio ont été caractérisées à l’aide de 24 caractères agro-morphologiques dans un dispositif en blocs de Fischer à trois répétitions. Une variabilité morphologique moyenne a été observée entre les accessions. Ceci est confirmé par l’analyse des composantes principales qui a permis d’expliquer 51,516 % de la variabilité. La classification ascendante hiérarchique (CAH) a mis en évidence quatre groupes : (1) les accessions à cycle court et à faible production, (2) les accessions à cycle intermédiaire et à production moyenne, (3) les accessions à cycle long et à forte production et (4) les accessions à cycle long mais à faible production. L’analyse factorielle discriminante (AFD), à travers le test de Wilks, a montré que sept variables sur 24 permettent de discriminer les groupes. Ils peuvent constituer des critères de base pour différencier les variétés de fonio en Côte d‘Ivoire. Les groupes identifiés peuvent servir de point de départ pour une amélioration de l’espèce. Mots clés : Digitaria exilis, variabilité agro-morphologique, accession, fonio, Côte-d’Ivoire   English Title: Agro-morphological characterization of Fonio accessions collected in northern Cote d’Ivoire Fonio [Digitaria exilis Stapf (Kippist.)], a small grain cereal, grown and consumed in northern Côte d’Ivoire, is a key food security for the people of this area. However, no study on the genetic diversity of landraces has been carried out to date. The present study aims to assess the level and structure of agro-morphological variability. Thus, 217 fonio accessions were characterized using 24 agro-morphological characters in a randomized complete block design (RCBD) with three replicates. An average morphological variability was observed between the accessions. This is confirmed by the analysis of the principal components which made it possible to explain 51.516 % of the variability. The ascending hierarchical classification highlighted four groups: (1) short cycle and low production accessions, (2) intermediate cycle and medium production accessions, (3) long cycle and high production accessions and (4) long cycle but low production accessions. The discriminant factor analysis (AFD), through the Wilks test, showed that seven variables out of 24 allow to discriminate groups. They can constitute basic criteria to differentiate the varieties of fonio in Côte d‘Ivoire.The identified groups can serve as a starting point for improving the species. Keys words : Digitaria exilis, Agro-morphological variability, accession, fonio, Côte d’Ivoire

Conductivité thermique effective des roches partiellement saturées

Ce travail est dédié à l'évaluation de la conductivité thermique effective (CTE) des milieux poreux en conditions partiellement saturées à l'aide d'une méthode d'homogénéisation en deux étapes (basée sur le modèle Mori-Tanaka et la borne de Ponte-Casta\~{n}eda-Willis). L'utilisation dans le modèle d'une fonction de distribution en orientation (ODF) permets de prendre en compte l'isotropie transverse induite par les systèmes des pores. Considérée homogène à l'échelle macroscopique, la conductivité thermique effective est dépendante des propriétés physiques des phases subsidiaires. L'influence de la géométrie et de la distribution spatiale des inclusions sur la CTE ainsi que la dépendance avec le degré de saturation de la phase liquide sont quantifiés. Les capacités prédictives de la démarche proposée sont évalués par comparaison des simulations numériques avec les données expérimentales disponibles pour une argilite

Оптимизация общего содержания флавоноидов в спиртовом экстракте Persicaria pulchra (Bl.) Soják для ингибирования фермента α-глюкозидазы

Objectives. There has been a rapid increase in the number of diabetic patients since the past few decades in developed and developing countries. This rapid increase is accompanied by alarming costs of treatment. α-Glucosidase inhibitors are one of the most effective drugs employed for the reduction of postprandial hyperglycemia to manage Type 2 diabetes mellitus. Additionally, flavonoids, a group of natural substances, which are widely distributed in plants and possess variable phenolic structures, exhibit outstanding hypoglycemic activity and are considered as potential α-glucosidase inhibitors. In Vietnam, Persicaria pulchra (Bl.) Soják (P. pulchra) is employed in traditional medications. It possesses high flavonoid contents and its anti-diabetes ability has been hypothesized, although it has attracted less attention for investigation. Hence, the aim of this study is to optimize the condition of the P. pulchra extract to obtain the highest total flavonoid content and measure the bioactivities of P. pulchra, such as the anti-α-glucosidase and antioxidant activities.Methods. The effects of the extracting conditions, including the temperature, extraction time, liquid-to-solid ratio (LSR), and ethanol (C2H5OH) concentration, on the total flavonoid content are investigated via experiments and analyzed by the response surface methodology (RSM). Concurrently, the optimal extraction also determines the anti-α-glucosidase and antioxidant activities.Results. The optimal extraction condition for the highest flavonoid content (530 mg quercetin/g) is determined in 60 min, at 53°C, with LSR of 9.46 g/g and C2H5OH concentration of 62%. Moreover, the optimal plant extract exhibits good α-glucosidase inhibition with a half-maximal inhibitory concentration (IC50) of 22.67 mg/mL, compared to the positive control (acarbose −7.77 g/mL). Additionally, P. pulchra is proposed to be a potential antioxidant with an IC50 of ~12.68 µg/mL.Conclusions. The study confirmed the optimal extraction condition of P. pulchra that will obtain the highest total flavonoid content and revealed the potentials of P. pulchra in α-glucosidase inhibition and antioxidation.Цели. В последние десятилетия в развитых и развивающихся странах наблюдается быстрый рост числа больных диабетом, который сопровождается ростом стоимости лечения. Ингибиторы α-глюкозидазы являются одним из наиболее эффективных препаратов, применяемых для снижения постпрандиальной гипергликемии при лечении сахарного диабета 2 типа. Кроме того, флавоноиды, группа природных веществ, широко распространенных в растениях и содержащих различные производные фенола, проявляют значительную гипогликемическую активность и могут служить потенциальными ингибиторами α-глюкозидазы. Во Вьетнаме Persicaria pulchra (Bl.) Soják (P. pulchra) используется в народной медицине. Он обладает высоким содержанием флавоноидов и, предположительно, противодиабетическими свойствами, хотя исследован мало. Таким образом, целью настоящего исследования является оптимизация экстрагирования P. pulchra для получения наиболее высокого общего содержания флавоноидов, а также определение его биологической активности – анти-α-глюкозидазной и антиоксидантной. Методы. Экспериментально исследовано влияние условий экстрагирования, а именно температуры, времени экстракции, соотношения жидкость : твердое вещество и концентрации этанола, на общее содержание флавоноидов с помощью методологии анализа поверхности отклика. Показано, что оптимальные условия экстракции определяют анти-α-глюкозидазную и антиоксидантную активность.Результаты. Найдены оптимальные условия экстракции для получения максимального содержания флавоноидов (530 мг кверцетина/г): время экстракции 60 мин, температура 53 °С, отношение жидкость : твердое вещество 9.46 г/г и концентрация этанола 62%. Растительный экстракт, полученный в оптимальных условиях, проявляет хорошее ингибирование α-глюкозидазы с концентрацией полумаксимального ингибирования (IC50) 22.67 мг/мл по сравнению с положительным контролем (акарбоза – 7.77 г/мл). Выводы. Исследование выявило оптимальные условия экстракции P. pulchra, позволяющие получить наиболее высокое общее содержание флавоноидов, и подтвердило перспективы применения P. pulchra для ингибировании α-глюкозидазы и антиоксидантного окисления

Information-Geometric Indicators of Chaos in Gaussian Models on Statistical Manifolds of Negative Ricci Curvature

A new information-geometric approach to chaotic dynamics on curved statistical manifolds based on Entropic Dynamics (ED) is proposed. It is shown that the hyperbolicity of a non-maximally symmetric 6N-dimensional statistical manifold M_{s} underlying an ED Gaussian model describing an arbitrary system of 3N degrees of freedom leads to linear information-geometric entropy growth and to exponential divergence of the Jacobi vector field intensity, quantum and classical features of chaos respectively.Comment: 8 pages, final version accepted for publicatio

The first 62 AGNs observed with SDSS-IV MaNGA : I. Their characterization and definition of a control sample

We report the characterization of the first 62 Mapping Nearby Galaxies at the Apache Point Observatory active galactic nuclei (AGNs) hosts and the definition of a control sample of non-active galaxies. This control sample was selected in order to match the AGN hosts in terms of stellar mass, redshift, visual morphology and inclination. The stellar masses are in the range 9.4 < log M/M < 11.5, and most objects have redshifts ≤0.08. The AGN sample is mostly comprised low-luminosity AGN, with only 17 ‘strong AGN’ with L([O III]λ5007 Å) ≥ 3.8 × 1040 erg s−1. The inner 1–3 kpc of the control sample galaxies are dominated by the oldest (≥ 4Gyr) component, with a small contribution of intermediate age and young stars (<940 Myr). Examining the relationship between the stellar population properties and L([O III]), we find that with increasing L([O III]), the AGN exhibit a decreasing contribution from the oldest stellar population relative to control galaxies and an increasing contribution from the younger components (∼40 Myr).We also find a correlation of the mean age differences (AGN–control) with L([O III]), in the sense that more luminous AGNs are younger than the control objects, while the low-luminosity AGNs are older. These results support a connection between the growth of the galaxy bulge via formation of new stars and the growth of the Supermassive Black Hole via accretion in the AGN phase

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters