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Analysis of Coupled Surface Plasmon in LHM Mediated Dielectric Gap Multilayer Structure

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Photonic Sensors 2020年第2期10卷 113-122页

作者： Mohammed BENDJEBBOUR abdellatif cherifi Benamar BOUHAFS University of Tlemcen Faculty of SciencesTheoretical Physics LaboratoryTlemcen 13000Algeria

The purpose of this work is to investigate theoretically the characteristics of confined electromagnetic modes propagating along the interfaces of a multilayer *** one dimensional(1D)sensor is formed by stacking a left-handed material(LHM)layer between a SiO2-glass prism and a dielectric gap layer in contact with gold(Au).The results indicate that the total thickness of the LHM layer and dielectric gap,in optimum conditions,give the ability of tuning significantly the characteristics of the resonant modes correlated to surface plasmons(SPs)propagation along the interfaces of the designed *** considering two arrangements between LHM and Au,two opposite resonant behaviors observed in p-reflectance spectra are analyzed in the angular interrogation mode and discussed thoroughly.

关键词： Confined electromagnetic modes surface plasmon resonance sensor left-handed material

Inventory and Analysis of Phytodiversity along an Altitudinal Gradient in the Southern Slope of the Mount of Tessala (Western Algeria)

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Open Journal of Ecology 2015年第11期5卷 552-562页

作者： Houria Ouici Zoheir Mehdadi Kouider cherifi Laboratory of Plant Biodiversity Conservation and Valorization Faculty of Natural Sciences and Life University of Djillali Liabes Sidi Bel Abbes Algeria

Our work consists in inventorying and analyzing the phytodiversity along an altitudinal gradient of the southern slope of the mount of Tessala (north-western Algeria). For this purpose, we choose seven stations, inside each one of them floristic statements are realized. The inventory carries out on the whole of the stations made it possible to draw up a floristic list represented by 103 species, distributed on 39 botanical families dominated by Asteraceae, Poaceae, Lamiaceae and Brasicasseae. The biological spectrum of these species reveals the predominance of the hemicryptophytes and the therophytes, and on the physiognomical level, the vegetation of our stations allows distinguishing from the tree, shrubby, bushy and herbaceous formations. The processing data obtained by the factorial analysis of correspondences (AFC) and by ascending hierarchical classification (CHA) emphasize the existence of two groups of stations. A first group of stations are located in altitude, less degraded, more diversified and where in particular the phanerophyts dominate. A second group of stations are located in low altitude, little diversified and where the degradation of vegetable cover is important, resulting in the installation of the hemicryptophyts and the therophyts.

关键词： Mount of Tessala Phytodiversity Floristic Inventory AFC CHA

Quercus fagineasubsp. tlemcenensisStands in the Moutas Reserve (Tlemcen, Northwest Algeria)

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American Journal of Plant Sciences 2020年第1期11卷 80-90页

作者： Bouazza Naima cherifi Kouider Babali Brahim

The Zeen oak (Quercus faginea) is a forest species endemic to the western Mediterranean, very remarkable in Algeria;it is an oak with deciduous or semi-persistent leaves. Quercus faginea, is very polymorphic, especially in terms of leaf characteristics, so it would be represented in Algeria by two subspecies: Quercus faginea subsp. baetica (Webb) DC and Quercus faginea subsp. tlemcenensis (DC). The latter, which is of major taxonomic interest, is a species that still resists climatic fluctuations. This stand is a formation at the climatic stage, which covers a large part of the Moutas reserve (488 ha), appears from an altitude of 1100 m and is frequently found where humidity is high. For a decade, our attention has been drawn to its particular behaviour, linked to major processes of change in both climate and biological components. Through this study, we show the importance of this stand, which is in a regressive dynamic phase on which the incidence of disturbances is only the action of anthropogenic climatic factors. Despite its good adaptive strategy, Quercus faginea subsp. tlemcenensis is a species threatened by multiple anthropozoogenic impacts;the latter constitutes a direct threat to the preservation and renewal of biological resources as well as to the ecological balance of the area [1], but the dynamic value of Quercus faginea subsp. tlemcenensis remains appreciated with particular attention by scientists, foresters, conservators and local populations in the region.

关键词： Stand Moutas Reserve Taxonomy Anthropozoogenic Impacts Preservation

The Impact of Religious Dimension on Entrepreneurial Intention by Using PLS Approach --Case Study

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Economics World 2015年第3期3卷 137-144页

作者： Souar Youcef cherifi Djelloul Idrissi Mokhtar University Tahar Mouly of Saida Saida Algeria University Abou Bakr Belkaid of Tlemcen Saida Algeria University Mustapha Stambouli of Mascara Saida Algeria

In a complex environment resulted from the economic and technological changes, and the emergence of the uncertainty cases, the entrepreneurial thought knows a development in the determinants of entrepreneurial spirit, that has become a mechanism and a dynamic of the competitivety of international economies, starting by the construction of investment projects whether individual or collective, which are based on innovation and the use of technology as factors that have the ability to give business competitiveness and increase its economic efficiency, also that is through the creation of job opportunities and reaching the economic development. This research aims to study the effect of the religious dimension and the dimensions of entrepreneurial behavior on the entrepreneurial intention among youth who are interested in realizing entrepreneurial projects. The partial least squares approach （PLS） has been used in this study and it results that the religious dimension influences positively the entrepreneurial intention.

关键词： entrepreneurial behavior religious dimension entrepreneurial intention partial least squares approach (PLS)

Methane Steam Reforming on Supported Nickel Based Catalysts. Effect of Oxide ZrO2, La2O3and Nickel Composition

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Open Journal of Physical Chemistry 2013年第2期3卷 89-96页

作者： Akila Belhadi Mohamed Trari Chérifa Rabia Ouiza cherifi Laboratory of Chemistry of Natural Gas Faculty of Chemistry (USTHB) Algiers Algeria

The catalytic properties of Ni (4 and 10 wt%) supported on both La2O3 and ZrO2 were investigated for the methane steam reforming reaction between 475℃ and 700℃ at atmospheric pressure. The catalysts were prepared by the impregnation method and characterized by several techniques (atomic absorption, BET method, X-ray diffraction and TG-TPO). The catalytic activity of Ni/support systems strongly depends on both of the nature and physico-chemical properties of the support. No deactivation was observed in catalytic systems, whatever the reaction temperature indicating high stability of the catalyst.

关键词： Methane Steam Reforming Nickel Coke Supported Catalysts

Methane Steam Reforming on Supported Nickel, Effect of Nickel Content for Product Hydrogen

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Open Journal of Physical Chemistry 2016年第2期6卷 34-41页

作者： Akila Belhadi Souhila Boumaza Amar Djadoun Mohamed Trari Ouiza cherifi Laboratory of Chemistry of Natural Gas Faculty of Chemistry USTHB Algiers Algeria Department of Géologie FSTGAT USTHB Algiers Algeria Laboratory of Storage and Valorization of Renewable Energies Faculty of Chemistry (USTHB) Algiers Algeria

The steam reforming of methane over NiO/ZnO mixed oxides with different nickel contents was studied. Solids to x% Ni/ZnO (x = 4 and 10%) were deposited on ZnO by impregnation from nickel nitrate solution;after vaporization the solid is calcined at 500°C for 6 h. The catalysts were characterized by X-ray diffraction (XRD) and BET method, scanning electron microscopy (SEM) and temperature programmed reduction (TPR). The XRD patterns revealed the NiO phase for all calcined catalysts. The chemical analysis confirmed the theoretical values of nickel. The catalysts were pre-treated under hydrogen at 500°C in situ, overnight before testing for the steam reforming of methane reaction (CH4/H2O/Ar = 10/10/80) in the temperature range (475°C - 650°C) under atmospheric pressure. The activities of both catalysts were investigated in a fixed-bed reactor for the Methane Steam Reforming (MSR) reaction. Globally, it was shown that the catalyst 10% nickel content has an important effect on the catalytic performances of solids i.e. the better results of hydrogen production were obtained with 10% wt. Ni/ZnO (28 ′ 10-3 mol/g catalyst).

关键词： Nickel Catalysts ZnO Methane Steam Reforming Hydrogen

Isolation of Anti Ageing Molecules Secreted by Human Gingival Stem Cells. Protection of Collagen and Elastic Networks

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Journal of Cosmetics, Dermatological Sciences and Applications 2014年第3期4卷 156-165页

作者： Hafida cherifi Adrien Naveau Ludwig Loison Robert Bruno Gogly Dental Department A. Chenevier-H. Mondor Hospital Creteil France Dental Department A. Chenevier-H. Mondor Hospital Créteil France

Skin aging results in an imbalance between synthesis and degradation of the extracellular matrix. Overproduction of degradative enzymes (MMPs) and oxygen free radicals during chronological and photo-induced aging leads a degradation of the network and elastic skin collagen. Our previous work demonstrated that a culture supernatant of gingival stem cells had anti-aging activities in vitro, ex vivo and in vivo in humans. However, this culture medium is very complex and currently not responding to the European cosmetics regulation. After the analysis of the culture medium we have isolated 4 molecules interesting in terms of skin anti-aging activity: TIMP1, Selenium, Folic Acid and Glycin (TSAG). After the study of the most efficiency concentration of each molecule, the composition of TSAG is tested on irradiated UVA human dermal fibroblast and human skin. TSAG preserves the elastin and collagen network and inhibits the MMP1, MMP3 and MMP9 activities. The advantage of this mimetic solution of stem cells is to be stable, easily reproducible and non-human origin. The outlook for cosmetology seems interesting.

关键词： Human Gingival Stem Cell MMPs Collagen Elastin

Inhibition of elastin and collagen networks degradation in human skin by gingival fibroblast. In vitro, ex vivo and in vivo studies.

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Journal of Cosmetics, Dermatological Sciences and Applications 2011年第1期1卷 4-14页

作者： Bruno Gogly Francois Come Ferré Hafida cherifi Adrien Naveau Benjamin Philippe Fournier 不详

Skin aging shows an imbalance between synthesis and degradation of the extracellular matrix. The overproduction of degradative enzymes (MMPs) during the chronology- and photo-induced aging leads to a degradation of the elastic and collagen networks. In a model of collagen and elastin destruction, we showed that the gingival fibroblast was able to preserve these macromolecules by inhibiting the overproduction of metalloproteinases by overproduction of TIMP-1 and modulation of the inflammatory cytokines activity. The objective of this study is to evaluate the effect of the gingival fibroblasts on human skin. The results in vitro and ex vivo show that the gingival fibroblast protects the skin collagen and elastic network by the inhibition of MMPs which leads to an overproduction of the TIMP-1. Moreover, the gingival fibroblast modulates the activity of some enzymes responsible for the inflammation;they inhibit the IL-1β and stimulate the production of TGF-β1. In vivo studies with a duration of six months and 50 women with pronounced wrinkles show that the culture supernatant of gingival fibroblasts diluted to 5% leads to a statistically significant decrease in the number and length of wrinkles.

关键词： elastin collagen skin Matrix Metalloproteinases gingival fibroblast

Oral Manifestations of Neurofibromatosis Type 1

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Journal of Cosmetics, Dermatological Sciences and Applications 2019年第1期9卷 41-55页

作者： Hafida cherifi Benjamin Fournier Ariane Berdal Blake McAlpin Ishai-Yaacov Sitbon Bruno Gogly Henri Mondor Hospital Dental DepartmentParis Descartes UniversityParisFrance Laboratory of Molecular Oral Pathophysiology ParisFrance Rotschild Hospital Centre de reference MAFACEParis Diderot UniversityParisFrance Neuroimmunology Laboratory Department of Symptom ResearchDivision of Internal MedicineUniversity of Texas MD Anderson Cancer CenterHoustonUSA

Neurofibromatosis type 1 (NF-1) is a common genetic disorder with a highly variable phenotype. The disease affects both proliferation and differentiation of cells of neurectodermal origin. The presence of tumors is very common like benign nodular neurofibromas. Tumors with unclear prognosis may be present like plexiform neurofibromas whose prognosis is more uncertain. While many organs exhibit pathologies, most commonly affected are the nervous system, skin, gastrointestinal tract and heart. Oral abnormalities are also very common: 72% of NF-1 patients exhibit pathologies in oral mucosa, gums, maxillary and temporomandibular joints, and teeth. The incidence of NF-1 and its relationship to the prevalence of caries have been discussed in other researches. It is known that poor oral hygiene plays a key role in the development of periodontal disease and caries. Here we review the oral manifestations of neurofibromatosis type 1 that we illustrate by a patient followed in the center of rare diseases of the hospital Henri Mondor, clinical service in which we work.

关键词： Neurofibromatosis Type 1 Genetic Disorder Oral Tumor Jaw Abnormalities Periodontal Disease