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ON A CHARACTERIZATION OF THE S-ESSENTIAL SPECTRA OF THE SUM ANd THE PROdUCT OF TWO OPERATORS ANd APPLICATION TO A TRANSPORT OPERATOR

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Acta Mathematica Scientia 2015年第6期35卷 1285-1304页

作者： Salma CHARFI Sassia RAHALI département de Mathématiques Faculté des Sciences de Sfax Université de Sfax

In this paper, we develop some operational calculus inspired from the Fredholm operator theory to investigate the S-essential spectra of the sum and the product of two operators acting on a Banach space. Furthermore, we apply the obtained results to determine the S-essential spectra of an integro-differential operator with abstract boundary conditions in L1（[-a,a]×[-1,1]）（a〉0）.

关键词： Fredholm operator Fredholm perturbation S-essential spectra transport operator

Phenotypic variation in food utilization in an outbreak insect herbivore

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Insect Science 2018年第3期25卷 467-474页

作者： Roberto Quezada-garcia Alvaro Fuentealba Eric Bauce Faculté de Foresterie Géographie et Géomafique Département des Sciences du Bois et de la Forêt Centre d'Etude de la Forêt (CEF) Universite Laval Quebec City Quebec Canada

The effects of nutrition may have subtantial impact on insect evolution by shaping different components of phenotypes. The key to undestanding this evolutionary process is to know how nutritional condition affects additive and nonadditive components of the phenotype. However, this is poorly understood in outbreaking insects. We investigated the additive and nonadditive variation present in food utilization traits in spruce budworm individuals subjected to chronic nutritional stress. A total of 160 full-sib families of spruce budworm （Choristoneurafumiferana Clem.） were raised under laboratory condi- tions, feeding on 2 diets （high and low energy） during 3 generations. Variables tested were pupal mass, consumption rate （RCR）, growth rate （RgR）, approximate digestibility （Ad）, the efficiency of conversion of digested food （ECd） and the efficiency of conversion of ingested food （ECI）. Our results show that all traits tested presented a high percentage of nonadditive effects that modulate phenotype expression. We found a significant impact of family × diet interaction on pupal mass, RgR and ECd. Furthermore, these traits exhib- ited the greatest heritability. There was no evidence of presence of maternal effects. The results revealed that food utilization traits may evolve through epigenetics effects, such as phenotypic plasticity. This information can be used by modellers to improve forecast of spruce budworm population dynamics.

关键词： food utilization nutritional stress phenotypic plasticity spruce budworm

geochemical Mobility Associated to gold and Base Metal Occurrences of Mangodara Sector, in Southern Burkina Faso, Banfora greenstone Belts (West African Craton)

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Open Journal of geology 2023年第10期13卷 1024-1053页

作者： Bernadin gnamou Hermann Ilboudo Wilfried Antoine Bassou Toé Sâga Sawadogo Laboratoire géosciences et Environnement (LagE) Département des Sciences de la Terre Ouagadougou Burkina Faso

In the Mangodara area within the Banfora greenstone belts (Baoulé-Mossi domain of the West African Craton), our study focused on geochemical assessment of the mobility of major and trace elements. gold and base metal occurrences are hosted in highly metamorphic felsic (metarhyolite) and intermediate (metadacite and metaandesite) formations. Common mineral assemblages made up of staurolite - kyanite - pyrophyllite are interpreted to represent the metamorphosed equivalent of aluminous hydrothermal alteration. Associated felsic and intermediate volcanic rocks are enriched in Fe2O3, K2O (metaandesite, metarhyolite) and depleted in MgO, Al2O3, CaO, P2O5, Na2O (metarhyolite) and Fe2O3, MgO, CaO (metaandesite). Al2O3 depletion in mineralized kyanite-staurotide bearing metarhyolites suggests corroded minerals. Mineralized metarhyolites show enrichment in Au, Ag, Ba, Bi, Cr, Cu, Eu, La, Mo, Ni, Pb, S, Sc, V and depletion in As Sb Co, Sn, Zn while mineralized metaandesites show enrichment in Au, Ag, As, Mo, S, Sb and depletion in Co, Sn, Zn, Bi, Cr, Cu, Eu, Ni, Pb, Sc. Ba, La, V are immobile in metaandesites. Finally, Ag, As, Sn appear as geochemical vectors for gold exploration in the study area since gold mineralization is characterized by Au + Ba + Cu + Eu + La + Mo + Ni + S association in metarhyolites and Au + S + Sb + As + Ag + Bi in metaandesites.

关键词： geochemical Mobility Aluminous Alteration Metamorphism gold Base Metal Banfora greenstone Belts Mangodara

On M-theory on real toric fibrations

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Communications in Theoretical Physics 2021年第8期73卷 67-74页

作者： A Belhaj H Belmahi M Benali S-E Ennadifi Y Hassouni Y Sekhmani Equipe des Sciences de la matière et du rayonnement ESMaRDépartement de Physique Facultédes SciencesUniversitéMohammed V de RabatMorocco LHEP-MS Département de PhysiqueFaculte des SciencesUniversitéMohammed V de RabatMorocco

Borrowing ideas from elliptic complex geometry, we approach M-theory compactifications on real fibrations. Precisely, we explore real toric equations rather than complex ones exploited in F-theory and related dual models. These geometries have been built by moving real toric manifolds over real bases. Using topological changing behaviors, we unveil certain data associated with gauge sectors relying on affine lie symmetries.

关键词： real fibrations M-theory toric real manifolds affine lie symmetries

Penalty Algorithms in Hilbert Spaces

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Acta Mathematica Sinica,English Series 2007年第2期23卷 229-236页

作者： Jean Pierre dUSSAULT Hai SHEN André BANdRAUK département d'Informatique Faculté des Sciences.Université de Sherbrooke Viador inc Laboratoire de Chimie Théorique Faculté des Sciences Université de Sherbrooke

We analyze the classical penalty algorithm for nonlinear programming in Hilbert spaces and obtain global convergence results, as well as asymptotic superlinear convergence order. These convergence results generalize similar results obtained for finite-dimensional problems. Moreover, the nature of the algorithms allows us to solve the unconstrained subproblems in finite-dimensional spaces.

关键词： penalty methods infinite dimensional optimization

Free vibration of functionally graded sandwich plates using four-variable refined plate theory

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Applied Mathematics and Mechanics(English Edition) 2011年第7期32卷 925-942页

作者： L.HAdJI H.A.ATMANE A.TOUNSI I.MECHAB E.A.AddA BEdIA Laboratoire des Matériaux et Hydrologie Université de Sidi Bel AbbesSidi Bel Abbes 22000Algérie département de génie Civil Université Ibn KhaldounTiaret 14000Algérie département de génie Civil Faculté des Sciences de l'IngénieurUnivesité Hassiba Benbouali de ChlefChlef 02000Algérie

This paper uses the four-variable refined plate theory （RPT） for the free vibration analysis of functionally graded material （FgM） sandwich rectangular plates. Unlike other theories, there are only four unknown functions involved, as compared to five in other shear deformation theories. The theory presented is variationally consistent and strongly similar to the classical plate theory in many aspects. It does not require the shear correction factor, and gives rise to the transverse shear stress variation so that the transverse shear stresses vary parabolically across the thickness to satisfy free surface conditions for the shear stress. Two common types of FgM sandwich plates are considered, namely, the sandwich with the FgM facesheet and the homogeneous core and the sandwich with the homogeneous facesheet and the FgM core. The equation of motion for the FgM sandwich plates is obtained based on Hamilton＇s principle. The closed form solutions are obtained by using the Navier technique. The fundamental frequencies are found by solving the eigenvalue problems. The validity of the theory is shown by comparing the present results with those of the classical, the first-order, and the other higher-order theories. The proposed theory is accurate and simple in solving the free vibration behavior of the FgM sandwich plates.

关键词： functionally graded material (FgM) free vibration sandwich plate refinedplate theory (RPT) Navier solution

BEST APPROXIMATION FOR WEIERSTRASS TRANSFORM CONNECTEd WITH SPHERICAL MEAN OPERATOR

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Acta Mathematica Scientia 2012年第2期32卷 455-470页

作者： L.T.Rachdi N.Msehli département de Math'ematiques Facult'e des Sciences de Tunis2092 El-ManarTunisia département de Mathématiques et d'informatique Institut National des Sciences Appliquées et de Technologie de Tunis1080 TunisTunisia

Using reproducing kernels for Hilbert spaces, we give best approximation for Weierstrass transform associated with spherical mean operator. Also, estimates of extremal functions are checked.

关键词： Weierstrass transform spherical mean operator best approximation repro-ducing kernel extremal function

The Bafoussam volcanic series:origin and evolution of the volcanism along the Cameroon volcanic line

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Acta geochimica 2022年第6期41卷 1049-1068页

作者： Philippe Essomba gilles Chazot Nicaise Blaise Tchuimegnie Ngongang Arnaud Agranier Pierre Kamgang HervéBellon Philippe Nonnotte Pierre Wotchoko Innocent Badriyo département des Sciences de La Terre FacultéDes SciencesUniversitéde YaoundéIB.P.812YaoundéCameroun geo-Ocean CNRSIfremerUMR6538Univ Brest29280PlouzaneFrance département des Sciences de La Terre FacultéDes SciencesUniversitéde DoualaDoualaCameroun department of geology Higher Teacher Training CollegeUniversity of BamendaBambiliBamendaCameroon département de Séismologie et géologie Observatoire Volcanologique de Goma-RDCGomaRépublique Démocratique du Congo

The Bafoussam area in western Cameroon is part of the central Cameroon Volcanic Ligne(CVL).This study presents the mineralogy,major and trace element compositions,Sr-Pb-Hf isotopes,and new K-Ar geochronological data about mafic and felsic volcanic *** rocks belong to two different series:A transitional series made of basalts,basaltic andesite,and trachytes and an alkaline mafic series with basalts,hawaiites,and *** age data show that the transitional series belongs to the oldest part of the CVL and was emplaced between 47 and 35 *** alkaline volcanism is younger,with ages ranging from10 to 4.5 *** evolution in both series is accomplished through a fractional crystallization process,with the removal of olivine and clinopyroxene,while plagioclase does not seem to be a major crystallizing *** the samples are enriched in incompatible trace elements,but the rocks from the alkaline series have more fractionated REE patterns and high Nb content compared to the transitional mafic *** lavas have lower initial^(87)Sr/^(86)Sr and higher^(176)Hf/^(177)Hf and Pb isotopic ratios than the transitional *** La/Nb and high^(87)Sr/^(86)Sriratio are among chemical characteristics that show that some samples from the transitional series have interacted with a crustal component during their evolution in the *** cannot be used for discussing the mantle source of the volcanic rocks from this *** elements show that primary magmas for both series formed in a garnet-bearing mantle source,with higher partial melting degrees(3-5%)for the transitional magmas than for the alkaline magmas(g trace elements and isotopic ratios,we show that the Bafoussam lavas formed from two different mantle *** magmas formed from a pyroxenite-bearing enriched mantle with low Pb isotopic *** mantle source is present in all the oldest lavas from the *** magmas formed from an HIMU-like mantle sourc

关键词： Cameroon Volcanic Line Bafoussam Mafic volcanic rocks Felsic volcanic rocks Mantle source

Environments favorable to healthy lifestyles:A systematic review of initiatives in Canada

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Journal of Sport and Health Science 2018年第1期7卷 7-18页

作者： Tegwen gadais Maude Boulanger Francois Trudeau Marie-Claude Rivard département des sciences de l’activité physique Universitédu Québec à Montréal département de psychologie Universitédu Québec à Trois Rivières département des sciences de l’activité physique Université du Québec à Trois Rivières

Background: In recent years, a number of initiatives aimed at promoting healthy lifestyles in health-friendly environments have been *** purpose of this review is to synthesize initiatives conducted in Canada and documented in publications for the period 1995–2015 in order to gain a better understanding of their objectives and ***: A systematic review of Canadian initiatives published over the past 20 years was conducted from multiple databases(i.e., Scopus,SPORTdiscus, Pub Med, Academic search complete, ***, Cairn, and Erudit). In total, 264 publications were identified and retained for the final analysis based on 5 criteria:(1) publication between 1995 and 2015,(2) online availability,(3) research conducted in Canada,(4) main topic related to environments favorable to healthy lifestyles(EFHL), and(5) publication in French or ***: A sharp increase in the number of studies on EFHL was observed between 2010 and 2015(57%). Two major lifestyle components—physical activity and nutrition—and 2 environmental aspects—neighborhood and built environment—were the elements most frequently examined regarding adults(48%), young people(34%), and seniors(9%), using quantitative(60%) and qualitative(18%) methods. Furthermore, the analysis reveals a greater focus on the municipal(53%) than the national or provincial levels(31%).Conclusion: This work is a first map of Canadian studies related to EFHL. It clarifies the definition of EFHL and classifies its components. As well,it documents the issues raised, the research methods employed, and the role of stakeholders, while outlining a new research agenda that includes dimensions of EFHL formerly neglected by researchers, namely, political and sociocultural spheres of action.? 2018 Production and hosting by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-Nd license(http://***/licenses/by-nc-nd/4.0/).

关键词： Built environment Canada Favorable environment Healthy lifestyle Initiatives Neighborhood Nutrition Physical activity