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Aqueous solubility, vapor pressure and octanol-water partition coefficient of two phthalate isomers dibutyl phthalate and di-isobutyl phthalate contaminants of recycled food packages
No full textInternational audienc
The rise of women and their impact on firms' performance
No full textInternational audienceThis paper aims to understand how the presence of women in management positively affects firms' financial performance. In order to validate our hypotheses, we used a quantitative method to collect data and performed an inquiry by surveying the top 30 Lebanese firms. The results showed that the presence of women in management in Lebanon is not positively correlated with firms financial performance. Women occupying high managerial positions are most probably a member of the family owning the business, and therefore they are not directly concerned with the management of the business. Moreover, a large number of the surveyed females in our sample are married. Consequently, their priorities change, and they put their family before their career development
Lutte contre l’érosion et aménagement agricole dans la plaine de la Bekaa (Liban)
No full textInternational audienceWest Bekaa, Lebanon is threatened by water erosion. Some changes in the mechanism of land use could help optimize crop yield and limit the risk of erosion. Having used GIS-based methods and data from the soil map, a vegetation management plan is proposed. The latter is crossed with soil and slope sensitivity by adapting a qualitative approach. The types of crops proposed correspond to the land's potential sensitivity to erosion. The choice of the crops contributes to the protection of the soil and the dynamism of cultural change. Hence, only orchards would be avoided.El oeste de la llanura de la Bekaa libanés está amenazada por la erosión hídrica. Algunos cambios en los patrones de ocupación del suelo optimizarían los cultivos y limitarían el riesgo de erosión. Se propone un plan de ordenación de la vegetación apoyándose en los SIG, en los mapas de aptitud del suelo, y en la valoración cualitativa de su fragilidad y pendiente. La elección de los tipos de cultivo, cuestionando la huerta tradicional, debirían de considerar la erosión potencial del suelo y su necesaria protección.L'ouest de la Bekaa libanaise est menacé par l'érosion hydrique. Certaines modifications de l'occupation du sol pourraient permettre d'optimiser les cultures et de limiter le risque érosif. À l'aide d'un SIG et de la carte d'aptitude des sols, un plan d'aménagement du couvert végétal est dressé. Ce dernier est croisé avec la sensibilité du sol et celle de la pente en adoptant une approche qualitative. Le choix des cultures devrait tenir compte de la nécessité de la protection du sol et de la sensibilité potentielle à l'érosion. Nous montrons que les vergers seraient à éviter
Metamorphic angrite Northwest Africa 3164/5167 compared to magmatic angrites
No full textInternational audienceNorthwest Africa (NWA) 3164 and 5167 are two angrites with a granulitic texture unlike that of other angrites, with avariable, up to millimeter grain size. Besides mineralogical and chemical similarities to other angrites, NWA 3164 and5167 exhibit unique characteristics. Ca-rich olivine dominates (in NWA 3164: 49 vol%, Fo57; NWA 5167: 40 vol%,Fo59). Fassaitic clinopyroxene is the second major phase (in NWA 3164: 29 vol%; in NWA 5167: 36 vol%) with a significantTschermak component. In addition, two Al-rich phases are present: plagioclase An99 and hercynitic spinel (6 and 7 vol%respectively for NWA 3164; 17 and 4 vol% respectively for NWA 5167). Heavily weathered iron sulfide and kamacite, (9 wt%in NWA 3164; 4 wt% in NWA 5167) are the remaining minor phases, a unique feature among angrites. All mineral phases arehomogeneous. Like other angrites, NWA 3164 and 5167 exhibit a superchondritic Ca/Al ratio, with negligible amounts ofalkalis and very low silica content. The presence of metal results from the incorporation of exogenous iron following impact.Subsequent annealing resulted in the observed granulitic texture. Major element composition indicates that both NWA 3164and 5167 are derived from a picritic angrite precursor after incorporation of metal and annealing.After correction for iron and Fo90 olivine incorporation, bulk rock REE abundances of both NWA 3164 and NWA 5167appear lower than those of quenched angrites, showing the lowest absolute abundances among angrites. Laser ablation inductivelycoupled plasma mass spectrometry (LA-ICP-MS) analyses of clinopyroxene, olivine and anorthite indicate that differenceof Rare Earth Element (REE) abundances between NWA 3164 and NWA 5167 can be explained by adding traces ofphosphate to NWA 3164. NWA 3164/5167 trace elements abundances are similar, showing depletion in volatile elementsand enrichment in refractory lithophile elements such as Ca, Ti, and Al. The most incompatible elements are depleted as well,unlike other angrites. This indicates that the source of these younger angrites was more depleted in incompatible elementswhen compared to the older magmatic angrites. The low Hf/W is understood as the result of exogenous iron incorporationand therefore the Hf/W andWisotopic heterogeneity of the angrite parent body (APB) mantle is secondary. Comparison withother angrites suggests that iron incorporation may be necessary to explain their low Hf/W and W isotopic compositions
First principles account for large changes in electronic structure and bonding from LaCu to LaCuMg and LaCuMg4
No full textInternational audienceIncreasing amounts of magnesium in LaCu intermetallic are shown to bring drastic electronic, chemical and mechanical changes. Based on DFT methodologies this is quantified for the cohesive energies, relative charge transfers, bulk modules, electronic structures and bonding properties for the three compounds LaCu, LaCuMg and LaCuMg4. Particularly the cohesive energies increase with Mg amounts: This is illustrated by the increasing number of pair interactions: While in the binary the bonding is ensured by La–Cu, in the ternaries La–Cu, La–Mg and Cu–Mg interactions contribute to the bonding with the extra electrons brought by Mg occupying bonding states. Along the series, increasing magnesium contents lead to moderate increase of the compressibility
High molecular hydrocarbons characterization for industrial and environmental applications
No full textInternational audienceOil industry accidents and wastes impose an aquatic environmental threat. Remediation techniques and models neglect the extraction of high molecular hydrocarbons due to their challenging experimental characteristics determination. In this presentation, we are going to talk about the different experimental devices we used for the determination of the vapor pressure, partition coefficient and the aqueous solubility of high molecular weight hydrocarbons
Study of culinary sayings in traditional Lebanese recipes by means of molecular gastronomy
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Impact du changement climatique et des événements extrêmes sur l'architecture des arbres : implication sur les dépérissements de forêts
No full text[Departement_IRSTEA]Territoires [TR1_IRSTEA]SEDYVINInternational audienceGlobal climate models agree in predicting a warmer climate on most continental areas, with more frequent extreme events such as heat waves and repeated or exceptional droughts. By increasing drought stress, global warming is a direct threat to forest health and survival in all types of forest ecosystems around the world. Two physiological mechanisms can be involved, separately or simultaneously, in tree decline or mortality during these stressing events: hydraulic failure and carbon starvation. Study goals: We present a study performed as an international effort to understand the influence of climate change and extreme events on the architectural development of forest trees, mainly conifers, in several countries. We discuss its potential contribution to forest decline and die-back. Fourteen conifers and one broadleaved species from Europe, USA and Canada were studied with the same protocol. In 47 sites as a whole, nearly 11000 twigs, from 2300 branches of 470 trees were sampled between 2005 and 2014, some of them repeatedly every year or few years. Branch and trunk length growth, architectural development (branching and polycyclism rates) and reproduction were retrospectively measured from morphological markers over a period of 10 to 45 years according to species. Needle or leaf number per growth unit, size and life span were measured on a subsample of twigs. Study sites include four experimental designs with climate manipulation in controlled conditions: rain exclusion, irrigation or heating and combinations of heat and drought on one of them. A phenological survey was performed on three of them to monitor monthly tree architectural development. Study sites cover conditions going from the limit of the desert to the tree line in mountains. We developed a generic architectural model for conifer trunks or branches, based on the relationships between climate and all measured parameters of tree architecture and needles. It aims at simulating the immediate consequences and after-effects of climate stresses on tree architecture and leaf area, for 10-year periods. In both Europe and Northern America, repeated or extreme droughts, heat waves and other stresses considerably reduced tree and branch vigour for all species at all sites, leading to reduced branch length and tree height growth, low polycyclism and branching rates, shorter and narrower than normal needles or leaves, and small number of needles or leaves per growth unit. A strong reduction of the life span of leaves and needles for evergreen species was also measured. Thus a significant leaf area deficit was observed and modelled during or just after but also several years after severe stresses. Two mechanisms explained the long lasting legacies of these stresses: (i) the slow recovery of the number of active twigs, due to the twig deficit induced by a low branching rate during and after the stress, limiting the number of leaves and needles, and (ii) the persistence, for many years on some species, of the cohorts of small leaves and needles formed in the bad years. The long lasting reduction of tree leaf area may contribute to carbon shortage and, in extreme cases, to delayed die-off by carbon starvation
Binding characteristics of molecularly imprinted polymers based on fungicides in hydroalcoholic media
No full textInternational audienceAn iprodione-imprinted polymer was prepared by copolymerization of methacrylamide and ethylene glycol dimethacrylate using a noncovalent imprinting approach. Methacrylamide was chosen using molecular dynamics simulations. To concentrate iprodione from hydro-alcoholic solutions, batch sorption of iprodione on the imprinted polymer were conducted. The equilibrium time for iprodione sorption is 20 min, and the corresponding kinetic mechanism follows the pseudo-second order indicating a strong interaction between iprodione and the imprinted polymer. Langmuir, Freundlich, and Dubinin-Radushkevich models were used to fit the isotherm of iprodione sorption. The imprinted polymer was found to be more efficient than the nonimprinted polymer for the uptake of iprodione, as revealed by its higher adsorption energy, affinity, and capacity. Finally, a selectivity study was conducted on the imprinted and the nonimprinted polymers to sorb three fungicides. It shows that the imprinted polymer could be used as a preconcentration phase in a multiresidue analysis of fungicides in hydroalcoholic medium
Software product lines evolution for valuable reusability
No full textInternational audienceNowadays, adopting software product line (SPL) development approach becomes a successful strategic decision in software development since the rapid time to market necessity is guaranteed by SPLs due to assets reusability [1,2]. However, the expansion of the market segment implies a boost of user's requirements that should be satisfied by quickly developing new products [1]. Thus, an agile evolution of SPLs becomes a necessity. The general purpose of a SPL is the automated construction of a new product based on the reusability of existing features [2]. A feature is a characteristic defined by the domain experts [3] that abstracts a set of software-related resources called assets. Thus, a feature model (FM) represents all the products of the SPL and permits capturing products commonalities and variability [3]. To generate a new product, a user selects a set of features via a process called configuration by respecting the constraints defined in the FM [2]. Despite that SPLs permit reusability, generating a new product that uses features related to different products is not supported by a classic FM [3]. In other words, if two products í µí± 1 and í µí± 2 leaded respectively to the injection of the features í µí°¹ 1 and í µí°¹ 2 in the í µí°¹í µí±, the latter does not support the generation of a new product í µí± 3 that uses both í µí°¹ 1 and í µí°¹ 2 since they refer to different products. However, in our desired approach we want to design evolved í µí°¹í µí±í µí± that make the previous operation feasible. In addition, to benefit from a valuable reusability, we are interested in focusing on the fact that a product can be constructed from a subset of the SPLs' features – regardless of referring to one or many products, or from a set of features that some of them are not part of the SPL. Thus, we should identify the features that are not part of the SPL once requested, connect them – if required – to the existing features that we still need from the SPL and integrate them in the SPL to be able to use them later. On the other hand, it is necessary to guarantee an agile evolution of the SPL, thus our approach should adopt mechanisms that automate as much as possible the software development process, minimize its overhead and simplify its complexity