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Reiterated homogenization of a laminate with imperfect contact:gain-enhancement of effective properties

Applied Mathematics and Mechanics(English Edition) 2018年第8期39卷 1119-1146页

作者： f.E.ALVAREZ-BORGES j.BRAVO-CASTILLERO M.E.CRUZ R.GUINOVART-DIAZ L.D.PEREZ-fERNANDEZ R.RODRIGUEZ-RAMOS f.j.sabina facultad de Matematica y Computacion Departamento de MatematicaUniversidad de La HabanaSan Lazaro y LHabana 4La HabanaCP 10400Cuba Departamento de Matematicas y Mecanica Universidad Nacional Autonoma de MexicoInstituto de Investigaciones en Matematicas Aplicadas y en Sistemas01000 CDMXAP 20-126M′exico Departamento de Engenharia Mecanica Universidade Federal do Rio de JaneiroPolitecnica/COPPECaixa Postal 68503Rio de JaneiroRJCEP 21941-972Brasil Departamento de Matematica e Estatistica Universidade Federal de PelotasCaixa Postal 354PelotasRio Grande do SulCEP 96010-900Brasil

A family of one-dimensional(1D) elliptic boundary-value problems with periodic and rapidly-oscillating piecewise-smooth coefficients is considered. The coefficients depend on the local or fast variables corresponding to two different structural scales. A finite number of imperfect contact conditions are analyzed at each of the scales. The reiterated homogenization method(RHM) is used to construct a formal asymptotic solution. The homogenized problem, the local problems, and the corresponding effective coefficients are obtained. A variational formulation is derived to obtain an estimate to prove the proximity between the solutions of the original problem and the homogenized problem. Numerical computations are used to illustrate both the convergence of the solutions and the gain of the effective properties of a three-scale heterogeneous 1D laminate with respect to their two-scale counterparts. The theoretical and practical ideas exposed here could be used to mathematically model multidimensional problems involving multiscale composite materials with imperfect contact at the interfaces.

关键词： reiterated homogenization method(RHM) imperfect contact variational formulation effective coefficient gain

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Interfacial effects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： f. j. sabina A.B.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the effects of dispersion of Bloch-floquet waves. A particular attention is given to structures containing interfaces between dissimilar media and localization of the electrical fields near such interfaces.

关键词： Piezoelectric periodic composites Interfaces Dispersion of Bloch-floquet waves

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Effect of Cerium Doping on Microstructure and Dielectric Properties of BaTiO_3 Ceramics

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journal of Materials Science & Technology 2011年第8期27卷 759-763页

作者： sabina Yasmin Shamima Choudhury M.A. Hakim A.H. Bhuiyan M.j. Rahman Department of Physics University of Dhaka Materials Science Division Atomic Energy Centre Department of Physics Bangladesh University of Engineering and Technology

A solid state reaction method was used to synthesize barium titanate （BT） and barium cerium titanate （BCT） ceramics at sintering temperature of 1473 K for 4 h. The effect of cerium （Ce） on the structure, microstructure and dielectric properties of BCT was investigated. The scanning electron microscopy （SEM） investigations revealed that the grain size increases with increasing Ce content. The X-ray diffraction （XI^D） patterns showed mostly the BT phase, where the lattice parameter decreased with the addition of Ce. The temperature dependence of dielectric constant showed decrease in the phase transition temperature with higher Ce content. The dielectric constant decreased slightly with increasing frequency. The direct current （dc） density-voltage characteristics of the ceramics showed ohmic behavior for both the BT and BCT. As the temperature increased, the dc resistivity of the ceramics decreased. The activation energy increased with increasing Ce content.

关键词： Cerium doped Ba1-xCexTiO3 Dielectric constant Current density

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Keratinocytes costimulate naive human T cells via CD2: a potential target to prevent the development of proinflammatory Th1 cells in the skin

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Cellular & Molecular Immunology 2020年第4期17卷 380-394页

作者： Christian Orlik Daniel Deibel johanna Küblbeck Emre Balta sabina Ganskih jüri Habicht Beate Niesler jutta Schröder-Braunstein Knut Schäkel Guido Wabnitz Yvonne Samstag Institute of Immunology Section Molecular ImmunologyHeidelberg UniversityIm Neuenheimer Feld 30569120 HeidelbergGermany Institute of Human Genetics Department of Human Molecular Geneticsand nCounter Core FacilityHeidelberg UniversityIm Neuenheimer Feld 36669120 HeidelbergGermany Department of Dermatology Heidelberg UniversityIm Neuenheimer Feld 44069120 HeidelbergGermany

The interplay between keratinocytes and immune cells,especially T cells,plays an important role in the pathogenesis of chronic inflammatory skin diseases.During psoriasis,keratinocytes attract T cells by releasing chemokines,while skin-infiltrating selfreactive T cells secrete proinflammatory cytokines,e.g.,IfN γand IL-17A,that cause epidermal hyperplasia.Similarly,in chronic graftversus-host disease,allogenic IfN γ-producing Th1/Tc1 and IL-17-producing Th17/Tc17 cells are recruited by keratinocyte-derived chemokines and accumulate in the skin.However,whether keratinocytes act as nonprofessional antigen-presenting cells to directly activate naive human T cells in the epidermis remains unknown.Here,we demonstrate that under proinflammatory conditions,primary human keratinocytes indeed activate naive human T cells.This activation required cell contact and costimulatory signaling via CD58/CD2 and CD54/LfA-1.Naive T cells costimulated by keratinocytes selectively differentiated into Th1 and Th17 cells.In particular,keratinocyte-initiated Th1 differentiation was dependent on costimulation through CD58/CD2.The latter molecule initiated STAT1 signaling and IfN γproduction in T cells.Costimulation of T cells by keratinocytes resulting in Th1 and Th17 differentiation represents a new explanation for the local enrichment of Th1 and Th17 cells in the skin of patients with a chronic inflammatory skin disease.Consequently,local interference with T cell–keratinocyte interactions may represent a novel strategy for the treatment of Th1 and Th17 cell-driven skin diseases.

关键词： keratinocytes inflammatory skin diseases psoriasis human T cells costimulation CD2 LfA-1 nonprofessional antigenpresenting cells Th1 cells Th17 cells

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Allelopathic Potential of Three Oil Enriched Plants against Seedling Growth of Common field Crops

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journal of Botanical Research 2019年第3期1卷 8-15页

作者： A K M Mominul Islam Md Mojidul Haque Oly Bhowmik sabina Yeasmin Md Parvez Anwar Department of Agronomy Bangladesh Agricultural UniversityMymensingh-2202 Agro Innovation Laboratory Department of AgronomyBangladesh Agricultural UniversityMymensingh-2202

Current study aims to investigate the allelopathic potential of the differentparts (leaf, bark, stem, twig and root) of three oil-enrich plant species ofBangladesh viz., jatropha curcus, Ricinus communis and Aphanamixispolystachya. The aqueous extract of those plant parts were diluted intofour different concentrations viz., 1:5, 1:10, 1:15, 1:20 (w/v) and testedagainst the seedling growth of jute, rice, wheat, radish, tomato, mungbeanand mustard under control laboratory condition. A control (distilled waterwithout extract) was also maintained in every cases and the bioassayexperiment was replicated thrice. The results of this research showed thatthe shoot and root growth inhibition of rice, wheat, jute, tomato, radish,mungbean and mustard by leaf, bark, stem, twig and root extracts of j.curcus, R. communis and A. polystachya varied significantly. Compareto the shoot growth, the root growth of the test species inhibited moreexcept j. curcus. The leaf and root have higher allelopathic potential thanany other parts of the studied plants. finally, it can be concluded here thatj. curcus plant extracts has higher allelopathic potential than other twoplants R. communis and A. polystachya. Therefore, j. curcus can be usedas a candidate plant for isolation and identification of allelopathic substancesfor the development of new natural herbicides.

关键词： Allelopathy jatropha Ricinus Aphanamixis Bio-diesel plants

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The Imago of Revolution Psychoanalysis and Class Consciousness An Introduction to Psychoanalysis and Class Consciousness （...and Some Extracts from the Dialectics Money/Death Drive）

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fudan journal of the Humanities and Social Sciences 2017年第4期10卷 485-508页

作者： Alessia j. Magliacane Centre Georg Simmel Ecole des Hautes Etudes en Sciences Sociales de Paris Paris France

for the purpose of the investigations, we propose in the present paper that we have been carrying out for some years into new perspectives for a Marxist Psychoanalysis; we try the consistence of Marxist psychoanalysis with the pre-Leninist idea of Class consciousness as developed in Economic and Philosophic Manuscripts of 1844 and in the unpublished books of Das Kapital (notably the law of the tendency of the rate of profit to fall). The roots of freudian Marxists (Reich and fenichel above all, but sabina Spielrein too) are put into a comparative analysis with Marxian psychiatry arising from the de-colonization process (fanon) and with the teaching of jacques Lacan about Marxist concepts such as plus value and reification, and eventually with the proposal on the political Unconscious developed by fredric jameson. finally, it comes the hypothesis that Psychoanalysis could correspond to Class consciousness.

关键词： Class consciousness Psychoanalysis Political Unconscious fantasy of destruction Drive to amass wealth Surplus-enjoyment Revolution Marx and Lacan

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青海都兰地区1835年来的气候变化──来自树轮资料

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第四纪研究 1997年第1期17卷 70-75页

作者：康兴成 L.j.Graumlich P.Sheppard 中国科学院兰州冰川冻土研究所兰州730000 亚利桑那大学树轮实验室

根据在青海都兰地区采集的树轮所建立的树轮年表资料，分析了年表与气候要素间的相关关系，讨论了1835年来的冷暖变化，得出：在近2000年间，该地区有10次冷期和11次暖期。其中，最长的暖期是819～1086年间，持续长达268年，显示了中世... 详细信息

根据在青海都兰地区采集的树轮所建立的树轮年表资料，分析了年表与气候要素间的相关关系，讨论了1835年来的冷暖变化，得出：在近2000年间，该地区有10次冷期和11次暖期。其中，最长的暖期是819～1086年间，持续长达268年，显示了中世纪暖期某些特征；最长的冷期是623～818年间，长达196年。而且，持续时间在100年以上的暖期只有两次，而冷期有5次。作者认为，在这1835年间，该地区是以寒冷气候为主的，但是自小冰期以来，气候明显转暖，这种变暖的趋势一直持续到现在。

关键词：树轮树轮年表气候变化青海

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利用树轮资料重建青海都兰地区过去1835年的气候变化

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冰川冻土 2000年第1期22卷 65-72页

作者：康兴成张其花 Lisa j. GRAUMLICH Paul.SHEPPARD 中国科学院兰州冰川冻土研究所甘肃兰州730000 LaboratoryofTree-RingResearch UniversityofArizone

根据青海都兰地区树木年轮样本，建立了目前我国最长的年轮年表序列（１８３５ａ），系统地与所在地区气候资料进行了综合分析，通过响应函数计算得出，该年表对温度因子的反映更为敏感一些。在响应面分析中发现，温度、降水与年轮宽度... 详细信息

根据青海都兰地区树木年轮样本，建立了目前我国最长的年轮年表序列（１８３５ａ），系统地与所在地区气候资料进行了综合分析，通过响应函数计算得出，该年表对温度因子的反映更为敏感一些。在响应面分析中发现，温度、降水与年轮宽度的关系呈现出随温度和降水的不同而不同，在温度低而降水量少的情况下，其线性相关性明显；但在温度较高和降水量较多时，树轮与两要素间的关系就显得不明显．另外，还对该年表与秋季平均温度的关系进行了论述，并认为在有季节冻土的高海拔地区，柏树的生长主要是在夏。

关键词：气候重建温度气候变化化资料古气候

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