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FINITE ELEMENT METHOD ON NUMERICAL SIMULATION OF STRATUM CORNEUM'S PENETRATION PROPERTY

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Applied Mathematics and Mechanics(English Edition) 2006年第4期27卷 469-475页

作者：刘宇红乔爱科 dirk Feuchter Gabriel Wittum 曾衍钧 Biomechanics and Medical Information Institute Beijing University of Technology Beijing 100022P. R. China Technical Simulation Group of the Interdisciplinary Center for Scientific Computing of University Heidelberg Im neuen Heimerfeld 36869120Germany Technical Simulation Group of the Interdisciplinary Center for Scientific Computing of University Heidelberg Im neuen Heimerfeld 368 69120Germany

How the outer substance could penetrate through the skin lies in the stratum corneum, because it is the main barrier in the multi-layers of the skin. Supposing the keratin cell with a special geometry as tetrakaidecahedron, the penetration property of stratum corneum was the key problem which was numerically simulated with finite element method. At first the discretization of the stratum corneum region was given in two steps： first, the discretization of the keratin cell; second, the discretization of fattiness that surrounds the keratin. Then there was the work of numerical simulation. In this procedure, the finite element method and the multi-grid method were used. The former was to obtain the discretization of basic elements; the latter was to decrease the high frequency error. At last the visualization of the numerical simulation was shown.

关键词： stratum corneum tetrakaidecahedron discretization finite element method multi-grid method

A crucial step for molecular-scale electronics:a stable and reversible single-molecule switch

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National Science Review 2017年第5期4卷 666-667页

作者： Tingting Mei Dong Xiang dirk Mayer Key Laboratory of Optical Information Science and Technology Institute of Modern OpticsCollege of Electronic Information and Optical EngineeringNankai University

As the most fundamental element of modern logic and memory circuits in all electronic devices,molecular switches,storing digital information and route signals by changing the molecular conductance,have attracted inten... 详细信息

关键词： MOLECULAR switches MOLECULAR electronics

New fossil evidence of the early diversification of scarabs： AIIoioscarabaeus cheni （Coleoptera： Scarabaeoidea） from the Middle Jurassic of Inner Mongolia, China

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Insect Science 2012年第2期19卷 159-171页

作者： Ming Bai dirk Ahrens Xing-Ke Yang Dong Ren Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijingChina Zoologisches Forschungsmuseum Alexander Koenig BonnGermany College of Life Sciences Capital Normal UniversityBeijingChina

Scarabaeoidea are known from the Lower Jurassic and may have originated in the Triassic based on fossil evidence and phylogenetic research. However, the early diversification of Scarabaeoidea remains unclear due to the lack of high-quality fossil evidence. Here we describe an exceptionally well-preserved new fossil of Scarabaeoidea, Alloioscarabaeus cheni gen. et sp. nov from the Middle Jurassic Jiulongshan Formation of Inner Mongolia, China. Based on a morphometric analysis using 17 landmarks of the hind wing of Alloioscarabaeus and 10 scarabaeoid families, we found that Alloioscarabaeus cheni gen. et sp. nov clearly does not belong to any of the known scarabaeoid families and, consequently, is a new family, Alloioscarabaeidae fam. nov., was erected. The discovery of Alloioscarabaeus brought further evidence for the early diversification of major scarab lineages which could allow more detail in the palaeobiogeography of the Scarabaeoidea and Northeast of China which might be one of the originating places or an important radiation place during the evolution of Scarabaeoidea. Alloioscarabaeidae were very likely not good diggers and might have fed on decaying organic materials. Based on the evidence we have now, we tend to believe that most families and some subfamilies of Scarabaeoidea were present in the Jurassic period.

关键词： Alloioscarabaeidae Alloioscarabaeus China geometric morphometrics,Jiulongshan Formation new family

Macrophage’s little helper: vitamin A directs alternatively activated monocyte-derived macrophages to tissue-resident macrophages

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Cellular & Molecular Immunology 2017年第10期14卷 805-808页

作者： dirk Schlüter Florian H Heidel Institute of Medical Microbiology and Hospital Hygiene Otto-von-Guericke University MagdeburgMagdeburg 39120Germany Organ-Specific Immune Regulation Helmholtz-Center for Infection ResearchBraunschweig 38124Germany Innere Medizin II Hämatologie und OnkologieUniversitätsklinikum JenaJena 07745Germany Leibniz-Institute on Aging Fritz-Lipmann-InstituteJenaGermany

Tissue-resident macrophages originate from the yolk sac in a Myb-independent manner and populate all organs during *** macrophages are a heterogeneous self-renewing population that adapt to the organ-specific local environment to contribute to tissue *** on the age,organ and inflammatory conditions,macrophages that are derived from hematopoietic stem cells(HSCs)in a Myb-dependent manner may also infiltrate organs and develop into tissueresident macrophages.

关键词： organs vitamin homeostasis

Expression of Epitope-Tagged SYN3 Cohesin Proteins Can Disrupt Meiosis in Arabidopsis

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Journal of Genetics and Genomics 2014年第3期41卷 153-164页

作者： Li Yuan Xiaohui Yang dirk Auman Christopher A.Makaroff Department of Chemistry and Biochemistry Miami University

a-kleisins are core components of meiotic and mitotic cohesin complexes. Arabidopsis contains genes encoding four a-kleisins. SYN1, a REC8 ortholog, is essential for meiosis, while SYN2 and SYN4 appear to be SCCI orthologs and function in mitosis. SYN3 is enriched in the nucleolus of meiotic and mitotic cells and is essential for megagametogenesis. It was recently shown that expression of SYN3-RNAi constructs in buds cause changes in meiotic gene expression that result in meiotic alterations. In this report we show that expression of SYN3 from the 35S promoter with either a c-terminal Myc or FAST tag causes a reduction in SYN1 mRNA levels that results in al- terations in sister chromatid cohesion, homologous chromosome synapsis female meiosis. and synaptonemal complex formation during both male and

关键词： Cohesin Cohesion Kleisin Synapsis Meiosis Sterility

Selected Recent Applications of Sparse Grids

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Numerical Mathematics(Theory,Methods and Applications) 2015年第1期8卷 47-77页

作者： Benjamin Peherstorfer Christoph Kowitz dirk Pfluger Hans-Joachim Bungartz Scientific Computing Group Dept.of Computer ScienceBoltzmannstr.385748 GarchingGermany Institutefor Advanced Study Technische UniversitätMünchenLichtenbergstr.2a85748 GarchingGermany Institute for Parallel and Distributed Systems University of StuttgartUni-versitätsstr.3870569 StuttgartGermany

Sparse grids have become a versatile tool for a vast range of applications reaching from interpolation and numerical quadrature to data-driven problems and uncertainty *** review four selected real-world applications of sparse grids:financial product pricing with the Black-Scholes model,interactive explo-ration of simulation data with sparse-grid-based surrogate models,analysis of simu-lation data through sparse grid data mining methods,and stability investigations of plasma turbulence simulations.

关键词： Sparse grids hierarchical decomposition adaptivity combination technique

Multi-criteria decision making methods to address rural land allocation problems:A systematic review

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International Soil and Water Conservation Research 2021年第4期9卷 490-501页

作者： Sintayehu Legesse Gebre dirk Cattrysse Esayas Alemayehu Jos Van Orshoven Department of Mechanical Engineering Center for Industrial ManagementTraffic&InfrastructureKU Leuven(University of Leuven)Celestijnenlaan 3003001LeuvenBelgium Department of Earth and Environmental Sciences Division of ForestNature and LandscapeKU Leuven(University of Leuven)Celestijnenlaan 200E3001LeuvenBelgium Department of Natural Resource Management Jimma UniversityJimmaEthiopia Department of Civil and Environmental Engineering JITJimma UniversityJimmaEthiopia

Land allocation has been an important issue in land use planning research *** allocation involves different multifunctional activities of maximizing environmental,economic and social ***-criteria decision making(MCDM)method is the most popular tool to optimize land allocation problems by considering decision variables,conflicting objectives,and ***,decision-makers face problems on how to optimize the land allocation while minimizing the conflicting trade-offs existing in the decision *** this review study,we aim at identifying and extracting information on MCDM methods to solve land allocation problems from English language articles published between 2000 and 2019 and indexed by four scientific literature databases(Web of Science,Science Direct,Scopus,Google scholar).To this end,we applied a systematic literature review approach,*** Preferred Reporting Items for Systematic Reviews and Meta-Analysis procedure(Moher et al.,2009),with a structured database search expression.120 articles were selected of which,after careful screening of title,keywords and abstract,69 were retained for detailed *** review study report compiles comprehensive information by classifying the papers into application area,optimization objectives,criteria used,decision techniques,publication year and study *** summary,we found that in the last two decades,the use of the MCDM method has increased,particularly in Europe and ***(analytical hierarchal process)is frequently used for multi-attribute land allocation problems with reference to ecotourism and ecosystem ***(linear programming)and SA(simulating annealing)methods are predominantly used to optimize multi-objectives complex agricultural and forest land allocation problems respectively.

关键词： Database Allocation Decision techniques PRISMA

Conductivity of Poly(methyl methacrylate)/Polystyrene/Carbon Black and Poly(ethyl methacrylate)/Polystyrene/Carbon Black Ternary Composite Films

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Chinese Journal of Polymer Science 2020年第3期38卷 288-297,I0007页

作者： Hua-Gen Xu Mu-Chao Qu Ya-Min Pan dirk WSchubert Institute of Polymer Materials Friedrich-Alexander-University Erlangen-NurembergMartensstr.791058 ErlangenGermany College of Materials Science and Engineering The Key Laboratory of Material Processing and Mold of Ministry of EducationZhengzhou UniversityZhengzhou 450002China Bavarian Polymer Institute Dr.Mack-Strasse 7790762 FiirthGermany

Poly(methyl methacrylate)(PMMA)/polystyrene(PS)/carbon black(CB)and poly(ethyl methacrylate)(PEMA)/PS/CB ternary composite films were obtained using solution casting technique to investigate double percolation *** both PMMA/PS/CB and PEMA/PS/CB ternary composite films,the CB particles prefer to locate into PS phase based on the results of calculating wetting coefficient,which is also confirmed by SEM *** conductivity of the films was investigated,and the percolation threshold(￠c)of both ternary composite films with different polymer blend ratios was determined by fitting the McLachlan GEM *** of PMMA/PS/CB ternary composite films showed a typical double percolation ***,due to the double emulsion structure of PEMA/PS polymer blends,the PEMA/PS/CB ternary composite films(PEMA/PS=50/50)showed a higher￠c,even CB only located in PS phase,which conflicts with the double percolation effect.A schematic diagram combined with SEM images was proposed to explain this phenomenon.

关键词： Double percolation effect Conductivity Ternary composite films Compatibility

Process Design for Hybrid Sheet Metal Components

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1518-1524页

作者： Rico Haase Roland Müller dirk Landgrebe Peter Scholz Matthias Riemer Fraunhofer Institute for Machine Tools and Forming Technology IWU

The global trends towards improving fuel efficiency and reducing CO;emissions are the key drivers for lightweight solutions. In sheet metal processing, this can be achieved by the use of materials with a supreme strength-toweight and stiffness-to-weight ratio. Besides monolithic materials such as high-strength or light metals, in particular metal–plastic composite sheets are able to provide outstanding mechanical properties. Thus, the adaption of conventional, wellestablished forming methods for the processing of hybrid sheet metals is a current challenge for the sheet metal working industry. In this work, the planning phase for a conventional sheet metal forming process is studied aiming at the forming of metal–plastic composite sheets. The single process steps like material characterization, FE analysis, tool design and development of robust process parameters are studied in detail and adapted to the specific properties of metal–plastic composites. In material characterization, the model of the hybrid laminate needs to represent not only the mechanical properties of the individual combined materials, but also needs to reflect the behaviour of the interface zone between *** on experience, there is a strong dependency on temperature as well as strain rate. While monolithic materials show a moderate anisotropic behaviour, loads on laminates in different directions generate different strain states and completely different failure modes. During the FE analysis, thermo-mechanic and thermo-dynamic effects influence the temperature distribution within tool and work pieces and subsequently the forming behaviour. During try out and production phase,those additional influencing factors are limiting the process window even more and therefore need to be considered for the design of a robust forming process. A roadmap for sheet metal forming adjusted to metal–plastic composites is presented in this paper.

关键词： Characterization Hybrids Interface Layered structures Processing Sheet forming