Evaluation of B3LYP, X3LYP, and M06-class density functionals for predicting the binding energies of neutral, protonated, and deprotonated water clusters

In this paper we assess the accuracy of the B3LYP, X3LYP, and newly developed M06-L, M06-2X, and M06 functionals to predict the binding energies of neutral and charged water clusters including (H_2O)_n, n = 2−8, 20), H_3O+(H_2O_)n, n = 1−6, and OH−(H_2O)_n, n = 1−6. We also compare the predicted energies of two ion hydration and neutralization reactions on the basis of the calculated binding energies. In all cases, we use as benchmarks calculated binding energies of water clusters extrapolated to the complete basis set limit of the second-order Møller−Plesset perturbation theory with the effects of higher order correlation estimated at the coupled-cluster theory with single, double, and perturbative triple excitations in the aug-cc-pVDZ basis set. We rank the accuracy of the functionals on the basis of the mean unsigned error (MUE) between calculated benchmark and density functional theory energies. The corresponding MUE (kcal/mol) for each functional is listed in parentheses. We find that M06-L (0.73) and M06 (0.84) give the most accurate binding energies using very extended basis sets such as aug-cc-pV5Z. For more affordable basis sets, the best methods for predicting the binding energies of water clusters are M06-L/aug-cc-pVTZ (1.24), B3LYP/6-311++G(2d,2p) (1.29), and M06/aug-cc-PVTZ (1.33). M06-L/aug-cc-pVTZ also gives more accurate energies for the neutralization reactions (1.38), whereas B3LYP/6-311++G(2d,2p) gives more accurate energies for the ion hydration reactions (1.69)

Caractérisation agropédologique des sols de mboltime dans la zone des niayes (Sénégal)

L'objectif de cette étude était de faire une évaluation de la fertilité physico-chimique de différents sols du village de Mboltime et de déterminer les similarités relatives. Les horizons de cinq fosses pédologiques (P1 , P2, P3, P4 et P5) ouvertes dans les zones dunaires et inter-dunaires ont servi à cet effet. Les résultats obtenus ont montré que les horizons de surface sont sableux à sablo-limoneux avec des pH et conductivité électrique variant selon les profils et les horizons. Seul le profil P4 a montré des sols acides et salés au niveau des horizons P4H1, P4H3 et P4H5. Les autres profils ont montré des sols neutres à légèrement alcalins et non salins. Les teneurs en matière organique et azote total ont été assez faibles dans les profils 1, 2, 3 et 5, et moyens dans le profil 4 avec un rapport C/N variant de 2,72 à 16,50. Les teneurs en Ca2+, Mg2+, Na+ et K+ varient suivant le C et N. Le cation le plus abondant dans les sols a été le Ca2+; suivi du Mg2+ et du Na+ alors que K+ a été le cation le moins abondant. L'analyse factorielle des correspondances (AFC) a permis de mettre en évidence deux groupes de sols en fonction de la salinité et de l'acidité. Un groupe I constitué de sols très salins et un groupe II constitué de sols non salins. Cette étude a mis en évidence deux contraintes majeures à la production végétale dans le village de Mboltime que sont la salinité et l'acidité des sols.Mots clés : Sol, Profil pédologique, Niayes, salinite ; Sénégal AGROPEDOLOGICAL CARACTERIZATION OF MBOLTIME SOILS IN NIAYES AREA (SENEGAL)The objective of this study was to evaluate physico - chemical properties of different soils from Mboltime village and relevant similarities. Horizons of five soil profiles (P1, P2, P3, P4 and P5) in the dune and inter-dune areaswere used for that purpose. The results showed variance in topsoil contents of sand with silt- loam, pH and electric conductivity according to the  profiles. Only the P4 profile presents acid and salty soil to the level asof horizons P4H1, P4H3 and P4H5. The other profiles presented neutral to slightly alkaline soil pH with limited salinity. The soil contents of organic matter, and total nitrogen were rather weak in the profiles 1, 2, 3 and 5, and moderate in profile 4. The C/N ratio values varied from 2.72 to 16.50 while soil contents of Ca2+, Mg2+, Na+ and K+ variations were according to C and N. The most abundant cations in land was Ca2+; followed by Mg2+, Na+ and K+ was the least abundant cationin soils. The factorial  correspondence analysis (FCA) showed two groups of soil according to  salinity and acidity mainly depending to high and low salinity respectively. This study showed two major constraints to land productivity in the village of Mboltime which are the salinity and the acidity of soils.Keywords : Soil, soil profile, salinity, Niayes, Senega

Development of a Smart Modular Heat Recovery Unit Adaptable into a Ventilated Façade

This paper presents the designing aspects and first experimental characterization of an adaptable Smart Modular Heat Recovery Unit (SMHRU) developed under the scope of the E2VENT Project. This SMHRU is being designed as a part of an adaptable renovation module for the retrofitting of multi-storey residential building from the 60's, 70's across Europe that embeds the SMHRU and an energy storage system based on a phase change material. This heat recovery unit will be adjustable to be integrated into the ventilated façade cavity, and able to recover heat from ventilation air, preheating the ventilation air in winter and precooling it in summer. This will allow an efficient combination of consumption reduction and acceptable air indoor quality. The first part of the paper presents designing considerations and thermal stationary analysis of the heat recovery unit, which is based on experimental correlations obtained for air-to-air compact offset-strip-fin plate heat exchangers. Secondly CFD analysis of the distributor of the SMHRU is presented. Finally prototype first performance estimation based on experimental results is presented.This work has been developed under the project “E2VENT: Energy Efficient Ventilated Façades” funded by the Horizon 2020 framework of the European Union, Project No. 637261

Larval ecology of mosquitoes in sylvatic arbovirus foci in southeastern Senegal

BACKGROUND: Although adult mosquito vectors of sylvatic arbovirus [yellow fever (YFV), dengue-2 (DENV-2) and chikungunya (CHIKV)] have been studied for the past 40 years in southeastern Senegal, data are still lacking on the ecology of larval mosquitoes in this area. In this study, we investigated the larval habitats of mosquitoes and characterized their seasonal and spatial dynamics in arbovirus foci. METHODS: We searched for wet microhabitats, classified in 9 categories, in five land cover classes (agriculture, forest, savannah, barren and village) from June, 2010 to January, 2011. Mosquito immatures were sampled monthly in up to 30 microhabitats of each category per land cover and bred until adult stage for determination. RESULTS: No wet microhabitats were found in the agricultural sites; in the remaining land covers immature stages of 35 mosquito species in 7 genera were sampled from 9 microhabitats (tree holes, fresh fruit husks, decaying fruit husks, puddles, bamboo holes, discarded containers, tires, rock holes and storage containers). The most abundant species was Aedes aegypti formosus, representing 30.2% of the collections, followed by 12 species, representing each more than 1% of the total, among them the arbovirus vectors Ae. vittatus (7.9%), Ae. luteocephalus (5.7%), Ae. taylori (5.0%), and Ae. furcifer (1.3%). Aedes aegypti, Cx. nebulosus, Cx. perfuscus, Cx. tritaeniorhynchus, Er. chrysogster and Ae. vittatus were the only common species collected from all land covers. Aedes furcifer and Ae. taylori were collected in fresh fruit husks and tree holes. Species richness and dominance varied significantly in land covers and microhabitats. Positive associations were found mainly between Ae. furcifer, Ae. taylori and Ae. luteocephalus. A high proportion of potential enzootic vectors that are not anthropophilic were found in the larval mosquito fauna. CONCLUSIONS: In southeastern Senegal, Ae. furcifer and Ae. taylori larvae showed a more limited distribution among both land cover and microhabitat types than the other common species. Uniquely among vector species, Ae. aegypti formosus larvae occurred at the highest frequency in villages. Finally, a high proportion of the potential non-anthropophilic vectors were represented in the larval mosquito fauna, suggesting the existence of unidentified sylvatic arbovirus cycles in southeastern Senegal

Development and Validation of a ReaxFF Reactive Force Field for Cu Cation/Water Interactions and Copper Metal/Metal Oxide/Metal Hydroxide Condensed Phases

To enable large-scale reactive dynamic simulations of copper oxide/water and copper ion/water interactions we have extended the ReaxFF reactive force field framework to Cu/O/H interactions. To this end, we employed a multistage force field development strategy, where the initial training set (containing metal/metal oxide/metal hydroxide condensed phase data and [Cu(H_2O)_n]^(2+) cluster structures and energies) is augmented by single-point quantum mechanices (QM) energies from [Cu(H_2O)_n]^(2+) clusters abstracted from a ReaxFF molecular dynamics simulation. This provides a convenient strategy to both enrich the training set and to validate the final force field. To further validate the force field description we performed molecular dynamics simulations on Cu^(2+)/water systems. We found good agreement between our results and earlier experimental and QM-based molecular dynamics work for the average Cu/water coordination, Jahn−Teller distortion, and inversion in [Cu(H_2O)_6]^(2+) clusters and first- and second-shell O−Cu−O angular distributions, indicating that this force field gives a satisfactory description of the Cu-cation/water interactions. We believe that this force field provides a computationally convenient method for studying the solution and surface chemistry of metal cations and metal oxides and, as such, has applications for studying protein/metal cation complexes, pH-dependent crystal growth/dissolution, and surface catalysis

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La tuberculose cutanée: observation de six cas confirmés au CHU Souro SANOU (CHUSS) de Bobo-Dioulasso (Burkina Faso)

La localisation cutanée de la maladie tuberculeuse demeure une forme rare et représente seulement 2,1 % des localisations. L'objet de cette étude est de rapporter le profil épidémiologique, anatomoclinique et évolutif des cas de tuberculose ganglio-cutanée diagnostiqués dans un CHU au Burkina Faso. La fréquence de la tuberculose cutanée est très faible au CHUSS. Six cas ont été diagnostiqués entre 2004 et 2010, soit une fréquence de un cas par an. La durée d'évolution des cas allait de deux jusqu'à dix ans avant leur diagnostic. Les lésions observées étaient: trois scrofulodermes, trois gommes, une tuberculose testiculaire associée à un mal de Pott, un cas de polyadénopathies et des cicatrices  atrophorétractiles dans la plupart des cas. Sur le plan  anatomopathologique, des granulomes tuberculoïdes ont été mis en évidence dans tous les cas avec une forte réaction tuberculinique à l'IDR. Sous antituberculeux pendant six mois, l'évolution a été bonne dans tous les cas mais au prix de séquelles cutanées cicatricielles inesthétiques. Son ampleur reste peut-être encore méconnue. Le renforcement du plateau technique du CHU et une bonne collaboration interdisciplinaire contribuerait à un meilleur diagnostic et prise en charge de cette affection