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The effect of landscape complexity and microclimate on the thermal tolerance of a pest insect

Insect Science 2018年第5期25卷 905-915页

作者： Lucy Alford Kevin Tougeron Jean-Sebastien Pierre Francoise Burel Joan van Baaren UMR 6553 ECOBIO Centre National de la Recherche Scientitique Universite de Rennes I Rennes Cedex France departement de Sciences Biologiques Insfitut de Recherche en Biologie Vegetale Universite de Montreal Montreal QC Canada Universite Europeenne de Bretagne (UEB) Rennes France

Landscape changes are known to exacerbate the impacts of climate change. As such, understanding the combined effect of climate and landscape on agroecosystems is vital if we are to maintain the fimction of agroecosystems. This study aimed to elucidate the effects of agricultural landscape complexity on the microclimate and thermal tolerance of an aphid pest to better understand how landscape and climate may interact to affect the thermal tolerance of pest species within the context of global climate change. Meteo- rological data were measured at the landscape level, and cereal aphids （Sitobion avenae, Metopolophium dirhodum and Rhopalosiphum padi） sampled, from contrasting landscapes （simple and complex） in winter 2013/2014 and spring 2014 in cereal fields of Brittany, France. Aphids were returned to the laboratory and the effect of landscape of origin on aphid cold tolerance （as determined by CTmin） was investigated. Results revealed that local landscape complexity significantly affected microclimate, with simple homogenous landscapes being on average warmer, but with greater temperature variation. Landscape complexity was shown to impact aphid cold tolerance, with aphids from complex land- scapes being more cold tolerant than those from simple landscapes in both winter and spring, but with differences among species. This study highlights that future changes to land use could have implications for the thermal tolerance and adaptability of insects. Fur- thermore, not all insect species respond in a similar way to microhabitat and microclimate, which could disrupt important predator-prey relationships and the ecosystem service they provide.

关键词： agroecosystems biological control cereal aphids climate change coldtolerance landscape ecology

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Existence of Entropy Solution for degenerate Parabolic-Hyperbolic Problem Involving p(x)-Laplacian with Neumann Boundary Condition

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Applied Mathematics 2024年第7期15卷 455-463页

作者： Mohamed Karimou Gazibo Duni Yegbonoma Frédéric Zongo Laboratoire de mathmatiques Fondamentales et Applications (LMFA) Dpartement de Mathmatiques cole Normale Suprieure Universit Abdou Moumouni de Niamey Niamey Niger Laboratoire Interdisciplinaire de Recherche en Sciences Appliques (LIRSA) cole Normale Suprieure Burkina Faso

We consider a strongly non-linear degenerate parabolic-hyperbolic problem with p(x)-Laplacian diffusion flux function. We propose an entropy formulation and prove the existence of an entropy solution.

关键词： Lebesgue and Sobolev Spaces with Variable Exponent Weak Solution Entropy Solution degenerate Parabolic-Hyperbolic Equation Conservation Law Leray Lions Type Operator Neumann Boundary Condition Existence Result

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A two variable refined plate theory for the bending analysis of functionally graded plates

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Acta Mechanica Sinica 2010年第6期26卷 941-949页

作者： Ismail Mechab Hassen Ait Atmane Abdlouahed Tounsi Hichem Abdesselem Belhadj EI Abbas Adda Bedia Laboratoire des Materiaux et Hydrologie Universite de Sidi Bel AbbesBP 89 Cite Ben M'hidi22000 Sidi Bel AbbesAlgerie departement de genie civil Faculte des Sciences de l'IngenieurUniversite Hassiba Benbouali de ChlefChlefAlgerie

Bending analysis of functionally graded plates using the two variable refined plate theory is presented in this *** number of unknown functions involved is reduced to merely four,as against five in other shear deformation theories. The variationally consistent theory presented here has, in many respects,strong similarity to the classical plate theory. It does not require shear correction factors,and gives rise to such transverse shear stress variation that the transverse shear stresses vary parabolically across the thickness and satisfy shear stress free surface *** properties of the plate are assumed to be graded in the thickness direction with their distributions following a simple power-law in terms of the volume fractions of the *** equations are derived from the principle of virtual displacements, and a closed-form solution is found for a simply supported rectangular plate subjected to sinusoidal loading by using the Navier *** results obtained by the present theory are compared with available solutions,from which it can be concluded that the proposed theory is accurate and simple in analyzing the static bending behavior of functionally graded plates.

关键词： FG plates Shear deformation theory Refined plate theory Higher-order theory Navier solution

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Dynamics of Super Quantum Correlations and Quantum Correlations for a System of Three Qubits

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Communications in Theoretical Physics 2016年第4期65卷 447-452页

作者： F.Siyouri M.El Baz S.Rfifi Y.Hassouni Laboratoire de Physique Theorique Departement de Physique Faculte des sciences Universite Mohammed V - AgdalAv. Ibn Battouta B.P. 1014 Agdal Rabat Morocco

The dynamics of quantum discord for two qubits independently interacting with dephasing reservoirs have been studied *** authors [***.A 88(2013) 034304] found that for some Bell-diagonal states(BDS)which interact with their environments the calculation of quantum discord could experience a sudden transition in its dynamics,this phenomenon is known as the sudden *** in the present paper,we analyze the dynamics of normal quantum discord and super quantum discord for tripartite Bell-diagonal states independently interacting with dephasing ***,we find that basis change does not necessary mean sudden change of quantum correlations.

关键词： super quantum discord normal quantum discord Bell-diagonal states measurement strength

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Phase noise modeling in LC oscillators implemented in SiGe technology

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Journal of Semiconductors 2013年第2期34卷 60-66页

作者： M.Bouhouche S.Latreche C.Gontrand Universite Mentouri Faculte des Sciences de l'IngenieurDepartement d'ElectroniqueLaboratoire Hyperfrequence & Semi-conducteur(LHS)25000ConstantineAlegria Universite de Lyon VilleurbanneF-69621France

This paper addresses phase noise analysis of a radiofrequency LC oscillator built around a SiGe heterojunction bipolar transistor （HBT） realized in a 0.35 um BiCMOS process, as an active device. First, we give a brief background to SiGe HBT device physics. The key point is to initiate quantitative analysis on the influence of defects induced during extrinsic base implantation on electric performances of this device. These defects are responsible for the current fluctuations at the origin of low frequency noise in BiCMOS technologies. Next, we investigate the effect of implantation defects as a source of noise in semiconductors on the phase noise of a radiofrequency LC oscillator. We observe their influence on the oscillator phase noise, and we quantify the influence of their energy distribution in the semiconductor gap. Second, we give a behavioral model of an LC oscillator con- taining a SiGe HBT as an active device. The key goal is to study the susceptibility of a radiofrequency oscillator built around a SiGe HBT to phase noise disturbance sources. Based on the time variance behavior of phase noise in oscillators, transient simulations （in the time domain） were used to analyze the time-dependent noise sensitivity of the oscillator.

关键词： SiGe heterojunction radiofrequency mixed-mode simulations oscillator phase noise

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Triaxial tension and compression tests on saturated lime-treated plastic clay upon consolidated undrained conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第12期15卷 3328-3342页

作者： Kuchvichea Kan Bertrand François department of Civil Engineering Institute of Technology of CambodiaPhnom PenhCambodia BATir department UniversitéLibre de BruxellesBrusselsBelgium ArGEnCo departement Universitéde LiègeLiègeBelgium

Lime-treatment of clayey soil significantly increases its shear and tensile ***,the tensile strength of lime-treated soils deserves careful investigation because it may provide an appreciable benefit for the stability of earth *** study investigates the tensile and shear strengths of an untreated and lime-treated(3%of lime)plastic clay at different curing times(7 d,56 d and 300 d),through triaxial tension and compression *** tension tests are performed using“diabolo-shaped”soil samples with reduced central section,such that the central part of the specimen can be under axial tension while both end-sections remain in axial *** undrained(CU)conditions with measurement of pore water pressure allow analyzing the failure conditions through effective stress and total stress *** results of triaxial tension tests reveal that the failure occurs under tensile mode at low confining pressure while extensional shear failure mode is observed under higher confining ***,a classical Mohr-Coulomb shear failure criterion must be combined with a cut-off tensile strength criterion that is not affected by the confining *** comparing shear failure under compression and tension,a slight anisotropy is observed.

关键词： Tensile strength Consolidated undrained(CU)triaxial test Lime-treated soils Failure criterion

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Impact of zinc and arginine on antioxidant status of weanling piglets raised under commercial conditions

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Animal Nutrition 2019年第3期5卷 227-233页

作者： Nadia Bergeron Frédéric Guay departement des Sciences Animales Université Laval

The effects of dietary zinc and L-arginine supplements on the weight gain,feed efficiency,antioxidant capacity and oxidative status of weanling piglets raised under commercial conditions were examined.A total of 288 piglets aged 21 d were fed for 15 d a diet supplemented or not with 2,500 mg/kg of zinc(provided as zinc oxide)and 1% L-arginine *** 4 treatments were distributed in a randomized complete block design with 6 initial body weight categories(12 animals per pen).Access to feed and water was ad *** were analyzed as a 2 x 2 factorial experiment using the SAS MIXED procedure,with zinc and arginine as the main independent *** collection day(d 8 and 15,samples were collected from the same 2 piglets in each pen before the morning feeding)was included as a third *** zinc supplement increased the average daily gain(ADG)from d 0 to 7.d 8 to 15 and d 0 to 15(0.289 vs.0.217 kg/d).average daily feed intake(ADFR)from d 8 to 15 and d 0 to 15(0.338 vs.0.279 kg/d)and the gain to feed(G:F)ratio from d 0 to 7 and d 0 to 15(0.86 vs.0.77)(Pdecreased the malondialdehyde concentration(zinc:4.37 vs.3.91 μmol/L,P= 0.005;arginine:4.38 vs.3.89 μmol/L,P = 0.002).Total antioxidant capacity and reduced glutathione(GSH)increased from d 8 to 15(0.953 vs.1.391 μmol/L,2.22 vs.3.37 μmol/L,Pdehyde concentration).The arginine supplement had a limited effect on growth performance and oxidative status under these conditions.

关键词： Zinc Arginine Weanling piglets Antioxidant status Growth performance

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Experimental Analysis and Damage Modeling of High-density Polyethylene under Fatigue Loading

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Acta Mechanica Solida Sinica 2016年第2期29卷 133-144页

作者： A.Djebli M.Bendouba A.Aid A.Talha N.Benseddiq M.Benguediab LPQ3M Faculte des sciences et des technologies Universite de Mustapha Stambouli Alegria LML Departement de Genie mecanique Universite Lille-l France HEI Ecole des hautes etudes d'ingdnieurs France Faculte de Technologie Universite de Sidi Bel Abess Alegria

In this study,an experimental analysis for determining the fatigue strength of HDPE-100 under cyclic loading is *** curve of cumulative fatigue damage versus number of cycles（D-N） was deduced from stiffness *** on the three stage damage trend,the remaining fatigue life is numerically predicted by considering a double term power damage accumulation *** model is found to be accurate,both in modeling the rapid damage growth in the early life and near the end of the fatigue *** results illustrate that the proposed model is capable of accurately fitting several different sets of experimental data.

关键词： HDPE semi-crystalline damage accumulation stiffness degradation

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SPECTRAL MAPPING THEOREM FOR ASCENT,ESSENTIAL ASCENT, deSCENT AND ESSENTIAL deSCENT SPECTRUM OF LINEAR RELATIONS

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Acta Mathematica Scientia 2014年第4期34卷 1212-1224页

作者： Ezzeddine CHAFAI Maher MNIF departement of Mathematics Faculty of Sciences of SfaxUniversity of SfaxTunisia

In [7], Cross showed that the spectrum of a linear relation T on a normed space satisfies the spectral mapping theorem. In this paper, we extend the notion of essential ascent and descent for an operator acting on a vector space to linear relations acting on Banach spaces. We focus to define and study the descent, essential descent, ascent and essential ascent spectrum of a linear relation everywhere defined on a Banach space X. In particular, we show that the corresponding spectrum satisfy the polynomial version of the spectral mapping theorem.

关键词： ascent essential ascent descent essential descent linear relations

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Fusion of spatiotemporal and thematic features of textual data for animal disease surveillance

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Information Processing in Agriculture 2023年第3期10卷 347-360页

作者： Sarah Valentin Renaud Lancelot Mathieu Roche CIRAD F-34398 MontpellierFrance ASTRE Univ MontpellierCIRADINRAEMontpellierFrance TETIS Univ MontpellierAgroParisTechCIRADCNRSINRAEMontpellierFrance departement de Biologie Universite de SherbrookeSherbrookeQuebecCanada

Several internet-based surveillance systems have been created to monitor the web for animal health *** systems collect a large amount of news dealing with outbreaks related to animal *** identifying news articles that describe the same outbreak event is a key step to quickly detect relevant epidemiological information while alleviating manual curation of news *** paper addresses the task of retrieving news articles that are related in epidemiological *** tackle this issue using text mining and feature fusion *** main objective of this paper is to identify a textual representation in which two articles that share the same epidemiological content are *** compared two types of representations(i.e.,features)to represent the documents:(i)morphosyntactic features(i.e.,selection and transformation of all terms from the news,based on classical textual processing steps)and(ii)lexicosemantic features(i.e.,selection,transformation and fusion of epidemiological terms including diseases,hosts,locations and dates).We compared two types of term weighing(i.e.,Boolean and TF-IDF)for both *** combine and transform lexicosemantic features,we compared two data fusion techniques(i.e.,early fusion and late fusion)and the effect of features generalisation,while evaluating the relative importance of each type of *** conducted our analysis using a corpus composed of a subset of news articles in English related to animal disease *** results showed that the combination of relevant lexicosemantic(epidemiological)features using fusion methods improves classical morphosyntactic representation in the context of disease-related news *** lexicosemantic representation based on TF-IDF and feature generalisation(F-measure=0.92,r-precision=0.58)outperformed the morphosyntactic representation(F-measure=0.89,r-precision=0.45),while reducing the features *** the features into lower granular

关键词： Animal disease surveillance Text mining Ranking Fusion

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