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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

Trends in incidence and management of cancer of the ampulla of Vater

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World Journal of Gastroenterology 2014年第29期20卷 10144-10150页

作者： Florian Rostain Samia Hamza Antoine Drouillard Jean Faivre Anne-marie Bouvier C?me Lepage Registre Bourguignon des Cancers Digestifs INSERM U866CHU de DijonFaculté de Médecine21079 Dijon CedexFrance

AIm: To provide trends in incidence, management and survival of cancer of the ampulla of Vater in a well-defined French population.

关键词： Cancer of the ampulla of Vater Incidence Survival Treatment Epidemiology

Numerical Study of Natural Convective Heat Transfer in an Air Filled Square Cavity Heated from Below and Symmetrically Cooled from the Sides with a Partition in the Hot Wall

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Fluid Dynamics & materials Processing 2023年第2期19卷 513-539页

作者： Farah Zemani-Kaci Amina Sabeur-Bendhina Laboratoire des sciences et Ingénierie maritimes Facultéde Génie MécaniqueUSTO-MBBP 1505 El M’naouerOran31000Algérie

A two-dimensional numerical study of laminar natural convection in a square enclosure filled with air with a wall partially heated on the bottom is *** heat source is located on the lower wall with different heated widths varied from 20 to 80%(ε=0.2–0.8)of the total width of the lower wall and different heights h=H/4 and H/2 of the *** effect of the partition height on the main system dynamics is investigated through solution of the two-dimensional Navier-Stokes equations and the energy equation by means of a finite volume method based on the SImPLE *** influence of the Rayleigh number(Ra=10^(3) to 10^(6))and the hot wall length is also *** is shown that the average Nusselt number grows whenεincreases and when h *** a given value ofεand h,the average Nusselt number increases as Ra *** is concluded that the partition height causes a decrease in the average Nusselt number.

关键词： Natural convection square enclosure heat source partial partition nusselt number

Phosphorus Use Efficiency of Bio-Based Fertilizers:Bioavailability and Fractionation

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Pedosphere 2016年第3期26卷 310-325页

作者： Céline VANEECKHAUTE Joery JANDA Peter A.VANROLLEGHEm Filip m.G.TACK Erik mEERS Laboratory for Analytical and Applied Ecochemistry Faculty of Bioscience EngineeringGhent University model EAU Département de Génie Civil et de Génie des EauxFaculté des Sciences et de GénieUniversité Laval

Although to date some technologies producing bio-based phosphorus(P) fertilizers have been proposed and implemented, the efficient use of the recovered products is still limited due to legislative constraints and lack of insights in the P release with time and in the corresponding mechanisms. The aim of this work was to evaluate the fertilizer performance in terms of P release and use efficiency of recovered struvite, FePO_4-sludge, digestate, and animal manure as compared to fossil reserve-based mineral triple superphosphate(TSP). First, product physicochemical characteristics and P fractions in the context of European fertilizer legislation were assessed. Next, a controlled greenhouse experiment was set up to evaluate plant reactions as well as changes of P availability in a sandy soil with high P status and a Rheinsand soil with low P status. Soil P fractions were determined in the extracts with water, ammonium lactate and CaCl_2, and in soil solution sampled with Rhizon soil moisture samplers. Based on all results, it is worth conducting long-term field trials to evaluate the P release effect of struvite and digestate as compared to animal manure and TSP on different soil types with varying P status. These products showed promise as sustainable substitutes for conventional P fertilizers and could contribute to a more efficient use of P in agriculture. A refined classification of P application standards/recommendations in terms of soil P status, soil texture, and fertilizer characteristics, next to the crop P demand, is recommended. moreover, the additional use of Rhizon samplers for determination of direct available P, including dissolved organic P, is proposed for better understanding and categorization of different P fertilizers in environmental and fertilizer legislations.

关键词： chemical soil analysis digestate nutrient recovery Rhizon samplers struvite

D-term Chaotic Braneworld in Supergravity Constrained by WmAP9 Data

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Communications in Theoretical Physics 2014年第3期61卷 397-402页

作者： A.Safsafi m.Ferricha-Alami H.Chakir J.Inchaouh m.Bennai Laboratoire de Physique de la matiére Condens'ee Equipe Physique Quantique et Applications Facultédes Sciences BenM’sik B.P. 7955 Université Hassan II-Mohammedia Laboratoire de Recherche Subatomique et Applications Facultédes Sciences Ben M’sik B.P. 7955 UniversitéHassanII-Mohammedia Laboratoire de Physique de la matiére Condens'ee Equipe Physique Quantique et Applications Facultédes Sciences BenM’sik B.P. 7955 UniversitéHassan II-Mohammedia Groupement National de Physique des Hautes Energies Focal Point LabUFR-PHE

We study a supergravity D-term chaotic inflationary model, in the context of the braneworld scenario, in particular we consider the Randal1-Sundrum model type 2. Using the latest release from the combination of WmAP9, eCmB, BAO, and Ho, we show that the inflation observables depend only on the number ore-folds N. We also derive all known spectrum inflationary parameters, which are widely consistent with WmAP9 data for a particular choice of values N specially for the scalar spectral index ns and the ratio r. However, the running of the scalar spectral index dns/dlnk is now excluded from the range given by the latest observational measurements.

关键词： D-term chaotic braneworld perturbation spectrum WmAP9

Potential generated by a massive inhomogeneous straight segment

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Research in Astronomy and Astrophysics 2011年第3期11卷 345-352页

作者： Nour-Eddine Najid El Haj Elourabi mohamed Zegoumou Equipe mécanique Statistique et Astronomie-Laboratoire de Physique Théorique et Appliquée Université Hassan Ⅱ Ain Chock-faculté des sciences Ain Chock BP 5366 maarif Casablanca morocco

The discoveries of binary asteroids have opened an important new field of research concerning the calculation of potential generated by irregular *** of them have an elongated shape.A simple model to describe the motion of a test particle in that kind of potential requires consideration of a finite homogeneous straight *** construct this model by adding an inhomogeneous distribution of mass. To be consistent with the geometrical shape of the asteroid,we explore a parabolic profile of the *** establish the closed analytical form of the potential generated by this inhomogeneous massive *** study of the dynamical behavior is fulfilled by the use of Lagrangian formulation,which allows us to calculate some two and three dimensional orbits.

关键词： asteroids—potential—inhomogeneous distribution

Farmers' contributions to the conservation of tree diversity in the Groundnut Basin,Senegal

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Journal of Forestry Research 2017年第5期28卷 1083-1096页

作者： Antoine Sambou Bienvenu Sambou Anders R?bild department of Geosciences and Natural Resource management Faculty of ScienceUniversity of Copenhagen Institut des sciences de l'Environnement (ISE) Facultdes Sciences et TechniqueUniversitCheikh Anta Diop(UCAD)

Tree diversity in West Africa is threatened by intensified land uses and salinization, and farmers’ role in conservation of tree species is unclear. We hypothesized that farmers contribute to conservation of tree diversity through protection of trees in their agroforestry landscapes and compared the diversity and structure of the tree vegetation across landscape classes. Inventories were carried out in three villages in the Groundnut Basin in Senegal, assessing tree diversity, density and crown cover. Tree diversity as assessed by species accumulation curves was high in forests, but cultivated landscapes had comparable or almost comparable diversity, especially in the cases where the forest was planted or was affected by charcoal production. However, the occurrence of exotic species was higher in cultivated parts of the landscape, and although many species were in common, ordination plots indicated that forests and cultivated landscapes to some degree had different species composition. Salinity had a strong influence on vegetation, not only in the tans (salt marshes) but also across the other landscape classes. In conclusion, agroforestry landscapes in the three villages harbor considerable tree diversity, but insufficient to fully conserve the tree species. We argue that informing and including farmers in tree management in the region will contribute to overall conservation of tree genetic resources.

关键词： Tree diversity Conservation-landscape classes Environmental factors Groundnut Basin

magnetic properties of mn-doped GaN with defects:ab-initio calculations

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Chinese Physics B 2011年第8期20卷 297-303页

作者： E.Salmani A.Benyoussef H.Ez-Zahraouy E.H.Saidi LmPHE Departement de PhysiqueFacult'e des SciencesUniversit'e Mohammed V-AgdalRabatMorocco LPHE Departement de PhysiqueFacult'e des SciencesUniversit'e Mohammed V-AgdalRabatMorocco

According to first-principles density functional calculations, we have investigated the magnetic properties of mn- doped GaN with defects, Ga1-x-yVGxmny N1-z-tVNzOt with mn substituted at Ga sites, nitrogen vacancies VN, gallium vacancies VG and oxygen substituted at nitrogen sites. The magnetic interaction in mn-doped GaN favours the ferromagnetic coupling via the double exchange mechanism. The ground state is found to be well described by a model based on a mn3＋-d5 in a high spin state coupled via a double exchange to a partially delocalized hole accommodated in the 2p states of neighbouring nitrogen ions. The effect of defects on ferromagnetic coupling is investigated. It is found that in the presence of donor defects, such as oxygen substituted at nitrogen sites, nitrogen vacancy antiferromagnetic interactions appear, while in the case of Ga vacancies, the interactions remain ferromagnetic; in the case of acceptor defects like mg and Zn codoping, ferromagnetism is stabilized. The formation energies of these defects are computed. Furthermore, the half-metallic behaviours appear in some studied compounds.

关键词： diluted magnetic semiconductor GaN:mn defects ab-initio magnetic properties

Existence results for unilateral contact problem with friction of thermo-electro-elasticity

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Applied mathematics and mechanics(English Edition) 2015年第7期36卷 911-926页

作者： H.BENAISSA EL-H.ESSOUFI R.FAKHAR Laboratoire de Recherche en mathématique Informatique et Sciences de l’Ingénieur (MISI) Laboratoire de Science des matériaux des Milieux et de la Modélisation (LS3M)Université Hassan 1

This work studies a mathematical model describing the static process of contact between a piezoelectric body and a thermally-electrically conductive foundation. The behavior of the material is modeled with a thermo-electro-elastic constitutive law. The contact is described by Signorini＇s conditions and Tresca＇s friction law including the electrical and thermal conductivity conditions. A variational formulation of the model in the form of a coupled system for displacements, electric potential, and temperature is de- rived. Existence and uniqueness of the solution are proved using the results of variational inequalities and a fixed point theorem.

关键词： static frictional contozt thermo-piezoelectric material Signorini's condi-tion Tresca's friction frictional heat generation variational inequality fixed point process

Anti-inflammatory and analgesic activities with gastroprotective effect of semi-purified fractions and isolation of pure compounds from mediterranean gorgonian Eunicella singularis

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Asian Pacific Journal of Tropical medicine 2015年第8期8卷 598-603页

作者： monia deghrigue Carmen Festa Lotfi Ghribi maria Valeria D’Auria Simona de marino Hichem Ben Jannet Abderrahman Bouraoui Laboratoire de développement chimique galénique et pharmacologique des médicaments (LR12ES09).Equipe de Pharmacologie marineFaculté de pharmacie de MonastirUniversité de Monastir department of Pharmacy University of Naples "Federico II" Laboratoire de chimie hétérocyclique produits naturels et réactivité. Equipe de chimie médicinale et produits naturels (LR11ES39)Faculté des sciences de MonastirUniversité de Monastir Laboratoire de chimie hétérocyclique produits naturels et réactivité.Equipe de chimie médicinale et produits naturels (LR11ES39)Faculté des sciences de MonastirUniversité de Monastir

Objective: To explore anti-inflammatory activities of organic extract and its semi-purified fractions(ethanol, acetone, methanol/dichloromethane) from the mediterranean gorgonian Eunicella singularis. methods: The anti-inflammatory and analgesic activities were evaluated, using the carrageenan-induced rat paw edema model and the acetic acid writhing test in mice. The gastroprotective activity was determined using HCl/et OH induced gastric ulcers in rats. The purification and structure elucidation of compound(s) from the more effective fraction were determined by chromatographic and spectroscopic methods and in comparison with data reported in the literature. Results: The fraction F-et OH showed an important antiinflammatory activity associated with significant analgesic and gastroprotective properties. The purification and structure elucidation of compound(s) from this fraction lead to the identification of one diterpenoid and four sterols. Conclusions: These results suggested that components from the active fraction can be used to treat various anti-inflammatory diseases.

关键词： Eunicella singularis Anti-inflammatory activity Analgesic activity Gastroprotective effect Diterpenoid Sterols