Theoretical study of the structural stability, electronic and magnetic properties of XVSb (X == Fe, Ni, and Co) half-Heusler compounds

The structural, electronic and magnetic properties of half-Heusler compounds XVSb (X $=$ Fe, Co and Ni) are investigated by using the density functional theory with generalized gradient approximation (GGA), and Tran-Blaha modified Becke-Johnson (TB-mBJ) exchange potential approximation. It is found that the half-metallic gaps are generally reasonably widened by mBJ as compared to the GGA approximation. The magnetic proprieties of XVSb (X $=$ Fe, Co and Ni) are well defined within mBJ with an exact integer value of magnetic moment. The band gaps given by TB-mBJ are in good agreement with the available theoretical data. The FeVSb exhibits a semiconductor nature. The CoVSb and NiVSb present half-metallic behaviour with total magnetic moment of $1\mu_\text{B}$ and $2\mu_\text{B}$ in good agreement with Slater-Pauling rule. These alloys seem to be a potential candidate of spintronic devices.Comment: 9 pages, 5 figure

Exact Gravitational Quasinormal Frequencies of Topological Black Holes

We compute the exact gravitational quasinormal frequencies for massless topological black holes in d-dimensional anti-de Sitter space. Using the gauge invariant formalism for gravitational perturbations derived by Kodama and Ishibashi, we show that in all cases the scalar, vector, and tensor modes can be reduced to a simple scalar field equation. This equation is exactly solvable in terms of hypergeometric functions, thus allowing an exact analytic determination of the gravitational quasinormal frequencies.Comment: 14 pages, Latex; v2 additional reference

Stakeholder-driven multi-attribute analysis for energy project selection under uncertainty

In practice, selecting an energy project for development requires balancing criteria and competing stakeholder priorities to identify the best alternative. Energy source selection can be modeled as multi-criteria decision-maker problems to provide quantitative support to reconcile technical, economic, environmental, social, and political factors with respect to the stakeholders' interests. Decision making among these complex interactions should also account for the uncertainty present in the input data. In response, this work develops a stochastic decision analysis framework to evaluate alternatives by involving stakeholders to identify both quantitative and qualitative selection criteria and performance metrics which carry uncertainties. The developed framework is illustrated using a case study from Fairbanks, Alaska, where decision makers and residents must decide on a new source of energy for heating and electricity. We approach this problem in a five step methodology: (1) engaging experts (role players) to develop criteria of project performance; (2) collecting a range of quantitative and qualitative input information to determine the performance of each proposed solution according to the selected criteria; (3) performing a Monte-Carlo analysis to capture uncertainties given in the inputs; (4) applying multi-criteria decision-making, social choice (voting), and fallback bargaining methods to account for three different levels of cooperation among the stakeholders; and (5) computing an aggregate performance index (API) score for each alternative based on its performance across criteria and cooperation levels. API scores communicate relative performance between alternatives. In this way, our methodology maps uncertainty from the input data to reflect risk in the decision and incorporates varying degrees of cooperation into the analysis to identify an optimal and practical alternative

Fluid-structure interaction and homogenization: from spatial averaging to continuous wavelet transform

Fluid-structure interaction (FSI) is classicaly modeled according a separated and local approach. It enables to take full advantage of the numerical methods specifically designed for each medium. However, it requires to take great care of the interface, and to exchange, between the algorithms, the information related to boundary conditions [1]. This treatment of the interface can quickly become too cumbersome in complex flow geometries, as in the industrial case study driving this work: an inviscid compressible flow interacting with French PWR fuel assemblies (Fig. 1a). In such specific applications, where the solid medium exhibits a discontinuous but periodic design, an homogenized and global approach is preferred [2]. Inspired by porous media [3, 4], multiphase flows, or Large Eddy Simulation (LES), it relies on a spatial averaging of the balance equations, thus allowing to remove all interfaces. However, such filtering techniques exhibit two major limitations: first, they do not deal properly with boundary conditions, due to the non-commutativity between the filtering operator and spatial derivatives, as detailed in [5, 6, 7] for LES; second, filtering implies loss of microscopic information, and thus requires a closure model to describe interactions between resolved and unresolved scales

Application of Artificial Neural Network (ANN) to Predict Soil Organic Matter Using Remote Sensing Data in Two Ecosystems

Concern over global problems induced by rising CO2 has prompted attention on the role of forests and pastures as carbon ‘storage’ because forests and pastures store a large amount of carbon in vegetation biomass and soil. Soil organic matter (SOM) plays a critical role in soil quality and has the potential to cost-effectively mitigate the detrimental effects of rising atmospheric CO2 and other greenhouse gas emissions that cause global warming and climate change(Causarano-Medina, 2006). SOM, an important source of plant nutrients is itself influenced by land use, soil type, parent material, time, climate and vegetation (Loveland &Webb, 2003). Important climatic factors influencing SOM include rainfall and temperature. Within the same isotherm, the SOM content increases with increase in rainfall regime. For the same isohyet, the SOM content...............

Effect of ethanolic extract of beet roots and leaves on motor coordination in male Wistar rats

زمینه و هدف: عدم تعادل حرکتی در اثر عوامل مختلفی از جمله ضایعات مغزی عصبی، مشکلات عضلانی، کم خونی و مصرف داروها رخ می دهد. گیاه چغندر با نام علمی Beta vulgaris L. دارای اثرات متنوع از جمله اثرات ضد التهابی، آنتی اکسیدانی، ضد استیل کولین استرازی و کاهش قند خون می باشد که در این مطالعه اثر عصاره اتانولی برگ و ریشه این گیاه بر تعادل حرکتی بررسی شده است. روش بررسی: در این مطالعه تجربی عصاره اتانولی ریشه و برگ گیاه چغندر به روش ماسراسیون تهیه شد. موش های صحرایی نر بالغ به طور تصادفی در 7 گروه 8 تایی تقسیم شدند و به مدت 25 روز آب مقطر، دوزهای مختلف عصاره ریشه (250،500 و mg/kg1000) و برگ چغندر (50 و mg/kg100) را به صورت داخل صفاقی دریافت کردند. روز 26، نیم ساعت بعد از آخرین تزریق قدرت حفظ تعادل حرکتی موش ها به وسیله روتارود اندازه گیری شد. یافته ها: عصاره ریشه چغندر در دوزهای 500 و mg/kg1000 سبب افزایش معنی دار در تعادل حرکتی شد (p0.05). نتیجه گیری: عصاره های ریشه و برگ گیاه چغندر باعث بهبود فعالیت حرکتی در موش های صحرایی نر بالغ می شود

Etude ethnobotanique de quelques lavandes marocaines spontanées

Le genre Lavandula est l'un des plus importants genres de la famille des Lamiacées et est riche en plantes à usage multiple, alimentaire, fourrager, aromatique, cosmétique et médicinal. Au Maroc, la bibliographie fait allusion à plusieurs espèces de ce genre, communément appelées lavandes, à écologie et phytogéographie diversifiées et dont d’une part la distinction taxinomique n’est pas des plus faciles et d’autre part l’éventualité d’un usage différent selon les localités et ou les espèces n’est pas investie. Aussi, l’objectif du présent travail est de rechercher les lavandes dans différentes régions du Maroc ; puis, par le biais d’investigations ethnobotaniques auprès d’herboristes et de vendeurs de plantes aromatiques et médicinales (PAM), inventorier leurs principaux usages traditionnels. Ainsi, durant l’année 2014, des prospections floristiques à la recherche de lavandes sauvages ont permis de repérer et localiser Lavandula stoechas L et L. atlantica Braun-Blanq , L. pedunculata Mill, L. multifida L, L. dentata L, L. maroccana Murb respectivement au plateau central « Oulmès, et Aguelmous » et au moyen atlas central « Ait Amro Ouali », la plaine de Sais « Ain Jerri », et en haut atlas occidental « bassin versant d’Ourika ». Les enquêtes ethnobotaniques menées auprès d’herboristes et vendeurs dans chaque site de récolte, via un questionnaire préétabli ont permis de dresser la liste des noms vernaculaires utilisés pour chaque espèce et ont révélé que les lavandes ont essentiellement des vertus thérapeutiques, que les feuilles et les fleurs sont les parties les plus utilisées surtout sous forme de décoction pour le traitement d’affections broncho-pulmonaires, gastrointestinales et uro-génitales.Mots clés : Lavandula, plantes aromatique et médicinales, enquête ethnobotanique, Maroc

Prevalence of human respiratory syncytial virus circulating in Iran

Respiratory syncytial virus (RSV) is a leading cause of acute respiratory infection during early childhood and is associated with a great burden on patients, parents, and society. While no treatment is yet available, results from recent phase 2 clinical trials of cell-entry inhibitors and RSV vaccines are promising. To prepare for introduction of these novel therapeutics, good understanding of its molecular epidemiology and continuous RSV surveillance data are necessary. This paper provides an overview of RSV prevalence and genotype distribution in Iran from 1996 to 2013. This meta-analysis includes 21 published studies. In total, 775 (18.7) of 4140 respiratory specimens were positive for RSV infection. The male-female ratio of RSV-positive patients was 1.5:1. Significant peaks of RSV infection were detected during the cold season (November-March). RSV infection was mainly observed in patients <2 years of age. Phylogenetic studies showed that genotypes GA1, GA2, GA5, and BA co-circulated in Iran in 2007-2013. This review highlights the necessity of introducing standard molecular surveillance programs to inform the epidemiological, clinical, and pathological characteristics of various RSV genotypes. Improved understanding of the molecular epidemiology will be useful for development of novel RSV therapeutics. © 2015 King Saud Bin Abdulaziz University for Health Sciences