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Distribution Pattern of Aquatic Macrophytic Community and Water Quality Indicators in Upper and Lower Litani River Basins, Lebanon
No full textInternational audienceIn spite of their important role in the structure and function of river ecosystems, aquatic macrophytes of freshwater bodies in Lebanon have so far received very little attention. In the present study, comparative analysis of the composition and spatial distribution of macrophytic communities and water quality indicators were assessed between Upper and Lower Litani River Basins in Lebanon. Five sites distributed along River Basins which are separated by Qaraoun Dam and its reservoirs were investigated during 2013-2014. A total of 35 of both submersed and emergent macrophytes were observed. FCA analysis revealed the presence of a heterogeneous spatial distribution pattern of the communities between the Upper and Lower River Basins. Two principle taxa units each characterizing either of the river basins were identified. Corresponding water quality analysis also showed heterogeneous spatial distribution and high levels of eutrophication of the Upper Basin and better quality conditions of the Lower Basin and CCA analysis highlighted the distinctive ecological features of macrophytic associations with respect to water quality parameters and trophic conditions of studied sites. These results clearly indicate the influence of nutrient enrichment in the determination of macrophyte assemblages and role of Qaraoun reservoir in the observed discontinuity of the taxa between the Upper and Lower basins and reducing the eutrophication level in the Lower Basin. Monitoring of macrophytes could, thus, be a reliable means to assess the ecological status of Litani River
Using the expert system to analyze loom performance
No full textInternational audienceIn this paper, the development of a warp tension simulation is presented. A system analysis of modern weaving machines led to a suitable simulation model to calculate the warp tension. The validation of the simulation demonstrates that the results correspond well with reality. In a second step, an improved model of this simulation was used in combination with a genetic algorithm and a gradient-based method to calculate optimized setting parameters for the weaving process. In order to do so, a cost function was defined taking into account a desired course of the warp tension. Actually, it is known, that a low and constant warp tension course is suitable for weaving. Using the genetic algorithm or the gradient-based method leads to optimized weaving machine parameters. Both algorithms do get nearly the same results for the optimized weaving machine setting. Applying the optimized setting parameters on a loom did not demonstrate that the productivity of a weaving machine can be raised. Analysis of the produced fabrics did not show an influence of optimization on the fabric quality. The reduction of warp tension was not sufficient in order to have an impact on the mechanical properties of the fabric. Thus, fabric defects could be eliminated using the optimized weaving machine settings
Onset of Spinal Cord Astrocyte Precursor Emigration from the Ventricular Zone Involves the Zeb1 Transcription Factor
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Acception herméneutique anaphatique de la tradition en Orient musical
No full textInternational audienceThis article explores the hermeneutical approach to the meaning of musical tradition in the Musical East, based on the work of Jean During. The recourse to the ternary logic of Cosinschi makes it possible to describe as anaphatic and sophianic this non-verbal hermeneutics, and thus as a counterpoint to the cataphatism of the musical hermeneutics of Kretzschmar, resulting from the expressionism and from the musical apophatism inherent to structuralism. This traditional musical hermeneutics is especially related to the Arab treaties of the modal grammatical tree structure and to the mystical interpretations developed within the framework of Christianity, Judaism and Islam.Cet article explore l’acception herméneutique du sens de la tradition musicale en Orient musical, à partir de l’œuvre de Jean During. Le recours à la logique ternaire des Cosinschi permet de qualifier d’anaphatique et de sophianique cette herméneutique non-verbale, et ce, en contrepoint du cataphatisme de l’herméneutique musicale de Kretzschmar, issue de l’expressionnisme, et de l’apophatisme musical, inhérent au structuralisme. Cette herméneutique musicale traditionnelle est surtout mise en relation avec les traités arabes de l’arborescence grammaticale modale et avec les exégèses mystiques développées dans le cadre du christianisme, du judaïsme et de l’islam
Influence of odor function and color symbolism in odor–color associations: a French–Lebanese–Taiwanese cross-cultural study
No full textInternational audienceThe olfactory and visual sensory systems appear to share robust and consistent associations. It is well known that culture specific experiences with odors may influence different aspects of odor perception such as intensity, pleasantness or edibility. Differences in terms of odor–color association might therefore be culturally specific. In order to determine the role of culture in odor–color associations, the responses of 155 French, 96 Lebanese and 110 Taiwanese subjects to the same 16 odorants were compared. The results highlight the role of culture and culinary habits on edibility ratings and color associations of some odors. Both perceptual and semantic factors seem to play a role in the odor–color associations in each country. Odor–color associations could indeed be affected by the function of odors in different countries. Culture-induced experiences influence the perception of odors familiarity, which will affect the prevalence of either perceptive (intensity, irritancy and hedonics) or semantic (nameability, familiarity) processing of these associations. Further studies should be conducted in order to understand the mechanisms underlying these cross-modal correspondences and the influence of cultural background and experience on them
Evaluation of Intra-Subband Power Allocation for a Downlink Non-Orthogonal Multiple Access (NOMA) System
No full textInternational audienceNon-Orthogonal Multiple Access (NOMA) schemes superpose multiple users in the power domain. It is commonly assumed that the achieved throughput in a downlink NOMA system increases with the channel gain difference between paired users. This paper investigates the accuracy of this claim when different intra-subband power allocation techniques are studied. Moreover, the Proportional Fairness (PF) scheduler is used as a resource allocation mechanism to highlight the importance of the choice of user pairing and of the intra-subband power allocation scheme. Results show that the achieved throughput does not always evolve in the same direction as the channel gain difference between paired users, owing to the choice of the intra-subband power allocation technique. In addition, it was found that the PF scheduler is not fully adapted to NOMA
Wine clarification with Rotating and Vibrating Filtration (RVF): Investigation of the impact of membrane material, wine composition and operating conditions
No full textInternational audienceFor the first time in the literature, a shear enhanced process (or dynamic filtration) called Rotating and Vibrating Filtration (RVF technology) was investigated for wine clarification. The impact of membrane material (hydrophilic PES and hydrophobic PTFE with a cut-off of 0.2 μm), wine composition (filtered wine, FW and Crude simulated wine, CSW) and operating conditions (transmembrane pressure and rotational frequency) are reported. RVF module is characterized by a complex hydrodynamic generated by a 3 flat blades impeller in a confined cell. An additional driving force is generated by rotational frequency and is taken into account to calculate the apparent and real permeabilities. Filtered wine (FW) generates an irreversible fouling whatever hydrophilic or hydrophobic membrane material. Even if PES membranes performances (Lp0 final = 1670 L.h-1.m-2.bar-1) were higher compared to those of PTFE membranes (Lp0 final = 170 L.h-1.m-2.bar-1), nor rotational frequency (mechanical stress), nor water rinsing did significantly remove or reduce fouling but, on the contrary, favors its compression and membrane plugging. Crude simulated wine (CSW) includes pectins, tannins and mannoproteins. CSW filtration runs demonstrated a mechanical impact onto fouling reduction with PES and PTFE membranes. However mechanical efficiency is moderated by material properties which generated irreversible fouling with different magnitudes. PTFE and PES permeability gains stand for +34% and +300% respectively. Finally, a “critical frequency” is defined above which a permeability increase and hydraulic resistance reduction is induced by rotational frequency (22 and 30 Hz for PES and PTFE membranes respectively)
The Chinese born globals of the Zhejiang province: A study on the key factors for their rapid internationalization
No full textInternational audienceWith the increased participation of emerging economies in the global economy, born globals (BGs) in emerging countries become significant players. However, researches on Chinese BGs are still very limited. The aim of this paper is to explore the key factors that influence the rapid internationalization of Chinese BGs and examine how these factors can explain the successful and quick integration of Chinese BGs into global market. Based on an Anglo-Saxon literature review, we identified six major factors explaining BGs’ rapid internationalization and compared them on two groups of Chinese SMEs (BGs and non-BGs) in an exploratory study. Based on the analysis of the exploratory study, we identified two key factors for the rapid internationalization of Chinese BGs, namely managers and networks. Then, we select four Chinese BGs and conducted a comparative case study in order to examine and understand the role of these two factors in their internationalization process. We conclude this paper with the contribution, implication, and limitation of our study, as well asthe perspective for our future research
The feasibility and efficacy of early-season releases of a generalist predator (Forficula auricularia L.) to control populations of the RAA (Dysaphis plantaginea Passerini) in Southeastern France
No full textAugmentative biological control is not commonly used in commercial orchards. We used an exclusion system to evaluate the potential of early-season releases of the European earwig (Forficula auricularia L., Dermaptera: Forficulidae) for control of the rosy apple aphid (Dysaphis plantaginea Passerini, Hemiptera: Aphididae) in the spring of 2009 in two pesticide-free apple orchards. In order to conduct this experiment we successfully reared earwigs with a high survival rate of nymphs (more than 96%) which may have commercial application. There were three treatments in the study: (i) a 'release treatment' where we confined the released earwigs in the canopy by using a barrier system; (ii) an 'exclusion treatment' where we blocked free access of earwigs into the canopy using the same barrier system; and (iii) a 'control treatment' that represented the natural situation. Contrary to expectations, earwig releases did not reduce D. plantaginea populations. In general, the abundance of natural enemies and their groups did not differ significantly among treatments, except for earwigs. We observed that the exclusion systems we used successfully kept both earwigs and ants away from tree canopies; total numbers on trees in the 'exclusion treatment' were significantly lower than on the other two treatments. Due to the complexity and difficulty of evaluating augmentative releases of natural enemies in open orchard conditions, we conclude that new technical approaches to control site conditions are needed when conducting such studie
Chemical Diversity and Antimicrobial Activity of Salvia multicaulis Vahl Essential Oils
No full textInternational audienceThe chemical compositions and antimicrobial activities of the essential oils (EOs) of aerial parts of Salvia multicaulis Vahl, collected during the same week from two different Lebanese regions, were investigated. The EOs were obtained by hydrodistillation using a Clevenger-type apparatus and characterized by GC and GC/MS analyses. The minimum inhibitory concentrations of these EOs were determined against one Gram-negative and two Gram-positive bacteria, one yeast, and five dermatophytes using the broth microdilution technique. One EO was notably active against Staphylococcus aureus, methicillin-resistant S. aureus and all of the Trichophyton species tested. Nerolidol was found to be the major compound in the active oil; nerolidol was also absent from the inactive oil. This study demonstrated that nerolidol shows antimicrobial activity and therefore significantly contributes to the antimicrobial potential of the oil. The chemical diversity of worldwide S. multicaulis EOs was analyzed, revealing that the EOs of the present study belong to two different chemotypes found in the literature. The nerolidol chemotype appears to be restricted to Lebanon and can be used as antimicrobial against external bacterial and fungal infections