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A longitudinal network analysis of social dynamics in rooks corvus frugilegus： repeated group modifications do not affect social network in captive rooks

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Current Zoology 2017年第5期63卷 379-388页

作者： Palmyre H. BOUCHERIE sebastian SOSA Cristian PASQUARETTA Valerie DUFOUR Institut Pluridisciplinaire Hubert Curien University of Strasbourg 23 rue Becquerel 67087 Strasbourg France Centre National de la Recherche Scientifique UMR 7178 67087 Strasbourg France Formerly affiliated with Grupo de Conducta Adaptativa e Interacci6n Psychology Faculty University of Barcelona 08035 Barcelona Spain

Numerous studies have investigated the remarkable variation of social features and the resulting structures across species. Indeed, relationships are dynamic and vary in time according to various factors such as environmental conditions or individuals attributes. However, few studies have investigated the processes that stabilize the structures within a given species, and the behavioral mechanisms that ensure their coherence and continuity across time. Here, we used a dynamic actor-based model, RSiena, to investigate the consistency of the temporal dynamic of relationships of a group of captive rooks facing recurrent modifications in group composition （i.e., the loss and introduction of individuals）. We found that changes in relationships （i.e., formation and removal） followed consistent patterns regardless of group composition and sex-ratio. Rooks preferentially interacted with paired congeners （i.e., unpopular attachment） and were more likely to form rela- tionships with individuals bonded to a current social partner （i.e., ＂friends of friends＂, or triadic closure）. The sex of individuals had no effect on the dynamic of relationships. This robust behav- ioral mechanisms formed the basis of inter-connected networks, composed of sub-structures of in- dividuals emerging from the enmeshment of dyadic and triadic motifs. Overall, the present study reveals crucial aspects of the behavioral mechanisms shaping rooks social structure, suggesting that rooks live in a well-integrated society, going far beyond the unique monogamous pair-bond.

关键词： corvids preferential attachment social interactions social network analysis temporal dynamics triadic closure.

Development of Ag-Cu-Zn-Sn brazing filler metals with a 10 weight-% reduction of silver and same liquidus temperature

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China Welding 2014年第4期23卷 25-31页

作者： Daniel Schnee Gunther Wiehl sebastian Starck Chert Kevin Umicore AG & Co. KG Business Unit Technical MaterialsRodenbacher Chaussee 4 63457 Hanau-Wolfgang Germany.

With BrazeTec BlueBraze the manufacturers in HVACR industry have an alternative filler metal with 10 weight-% less silver but same brazing temperatures. The performance of these new alloys has been evaluated in several tests. The evaluation included wetting investigations, metallographic examinations, joint strength at different temperatures and pulsation and corrosion resistance. The results of these tests will be presented in this paper.

关键词： silver brazing filler metal shear strength corrosion

Multiscale Finite ElementMethods for Flows on Rough Surfaces

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Communications in Computational Physics 2013年第9期14卷 979-1000页

作者： Yalchin Efendiev Juan Galvis M.sebastian Pauletti Department of Mathematics TAMUCollege StationTX 77843-3368USA Departamento de Matematicas Universidad Nacional de ColombiaBogotaColombia

In this paper,we present the Multiscale Finite Element Method(MsFEM)for problems on rough heterogeneous *** consider the diffusion equation on oscillatory *** objective is to represent small-scale features of the solution via multiscale basis functions described on a coarse *** problem arises in many applications where processes occur on surfaces or thin *** present a unified multiscale finite element framework that entails the use of transformations that map the reference surface to the deformed *** main ingredients of MsFEM are(1)the construction of multiscale basis functions and(2)a global coupling of these basis *** the construction of multiscale basis functions,our approach uses the transformation of the reference surface to a deformed *** the deformed surface,multiscale basis functions are defined where reduced(1D)problems are solved along the edges of coarse-grid blocks to calculate nodalmultiscale basis ***,these basis functions are transformed back to the reference *** discuss the use of appropriate transformation operators that improve the accuracy of the *** method has an optimal convergence if the transformed surface is smooth and the image of the coarse partition in the reference configuration forms a quasiuniform *** this paper,we consider such transformations based on harmonic coordinates(following *** and ***[*** and Applied Math.,LX(2007),pp.675-723])and discuss gridding issues in the reference *** results are presented where we compare the MsFEM when two types of deformations are used formultiscale basis *** first deformation employs local information and the second deformation employs a global *** numerical results showthat one can improve the accuracy of the simulations when a global information is used.

关键词： Multiscale finite elements on surfaces Laplace Beltrami resonance error harmonic maps

Morphology-and ion size-induced actuation of carbon nanotube architectures

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International Journal of Smart and Nano Materials 2018年第2期9卷 111-134,I0004页

作者： sebastian M.Geier Thorsten Mahrholz Peter Wierach Michael Sinapius aInstitute of Composite Structures and Adaptive Systems German Aerospace Center(DLR)BraunschweigGermany Institute of Adaptronics and Function Integration Technical University Carolo-Wilhelmina BraunschweigBraunschweigGermany

Future adaptive applications require lightweight and stiff materials with high active strain but low energy consumption.A suitable combination of these properties is offered by carbon nanotubebased *** made of carbon nanotubes(CNTs)are charged within an electrolyte,which results in an electrical field forming a double-layer of ions at their surfaces and a deflection of the papers can be *** now,there is no generally accepted theory for the actuation *** study focuses on the actuation mechanism of CNT papers,which represent architectures of randomly oriented *** samples are tested electrochemically in an in-plane set-up to detect the free *** elastic modulus of the CNT papers is analyzed in a tensile test *** influence of various ion sizes of water-based electrolytes is *** the tests,four parameters that have a significant influence on the mechanical performance of CNT papers were identified:the test conditions,the electrical charging,the microstructure and the ion *** of these influencing factors point to the mechanically weak inter-tube linking at which the actuation seems to take *** voltage-strain correlation suggests a combination of electrostatic and volumetric effects as the possible reason for CNT paper actuation.

关键词： Carbon nanotubes actuators carbon nanotube papers actuation mechanism ion size

Hepatocellular carcinoma: Therapeutic advances in signaling,epigenetic and immune targets

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World Journal of Gastroenterology 2019年第25期25卷 3136-3150页

作者： Daniel Neureiter sebastian Stintzing Tobias Kiesslich Matthias Ocker Institute of Pathology Cancer Cluster SalzburgParacelsus Medical University/Salzburger Landeskliniken(SALK)Salzburg 5020Austria Medical Department Division of Oncology and HematologyCampus CharitéMitteCharitéUniversity Medicine BerlinBerlin 10117Germany Department of Internal Medicine I Paracelsus Medical University/Salzburger Landeskliniken(SALK)and Institute of Physiology and PathophysiologyParacelsus Medical UniversitySalzburg 5020Austria Translational Medicine Oncology Bayer AGBerlin 13353Germany CharitéUniversity Medicine Berlin Berlin 10117Germany

Hepatocellular carcinoma(HCC)remains a global medical burden with rising incidence due to chronic viral hepatitis and non-alcoholic fatty liver *** of advanced disease stages is still *** first and second generation tyrosine kinase inhibitors,immune checkpoint inhibitors have become central for the treatment of *** modalities like epigenetic therapy using histone deacetylase inhibitors(HDACi)and cell therapy approaches with chimeric antigen receptor T cells(CAR-T cells)are currently under investigation in clinical *** of such novel drugs is closely linked to the availability and improvement of novel preclinical and animal models and the identification of predictive *** current status of treatment options for advanced HCC,emerging novel therapeutic approaches and different preclinical models for HCC drug discovery and development are reviewed here.

关键词： Liver cancer Immunotherapy Checkpoint inhibitors Targeted therapy Mouse model Biomarker Next-generation sequencing Non-alcoholic steatohepatitis Fibrosis Clinical trial

Particle shape characterisation and its application to discrete element modelling

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Particuology 2014年第1期12卷 80-89页

作者： Kenneth C.Williams Wei Chen sebastian Weeger Timothy J.Donohue Centre for Bulk Solids and Particulate Technologies Newcastle Institute for Energy and Resources The University of Newcastle Georg-Simon-Ohm University Nuremberg TUNRA Bulk Solids Newcastle Institute for Energy and Resources The University of Newcastle

Increasing importance has been placed on particle shape implementation within discrete element mod elling （DEM） in order to more accurately reflect the nonspherical behaviour of the bulk material being handled. As computational resources grow, complex particle shapes are increasingly being modelled as the associated simulation times become more realistic to provide timely solutions. The objective of this research is to assess particle shape descriptors through a digital image segmentation technique, and to further implement particle shape parameters into generation of corresponding irregular shaped DEM particles. Separated and lumped particle images were analysed and reconstructed through the devel opment of two distinct methodologies. Subsequently, various particle shape descriptors were obtained using combinations of image segmentation algorithms, including mathematical morphology processing, thresholding, edge detection, region growing, region splitting and region merging. DEM particles were subsequently created using particle shape results obtained above. Shape parameters of DEM particles were then examined and validated against the real particle shape parameters.

关键词： Particle shapesParticle morphologyImage segmentationDiscrete element modelling

Elastomeric lenses with tunable astigmatism

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Light(Science & Applications) 2013年第1期2卷 73-78页

作者： Peter Liebetraut sebastian Petsch Jens Liebeskind Hans Zappe Gisela and Erwin Sick Chair of Micro-optics Department of Microsystems EngineeringUniversity of FreiburgFreiburg 79110Germany

Microlenses fabricated using flexible elastomers can be tuned in focal length by application of controlled *** varying the strain azimuthally,the lenses may be deformed asymmetrically such that aberrations may be *** approach is used to tune the astigmatism of the tunable lenses,and it is shown that the generated wavefront may be accurately *** lens presented here has an initial focal length of 32.6 mm and a tuning range of 12.3 mm for approximately 10%applied *** range of directly tunable Zernike polynomials representing astigmatism is about 3 mm,while the secondary lens errors,which cannot be tuned directly,vary only by about 0.2 mm.

关键词： aberrations active or adaptive optics micro-optical devices polymers

Surface area-volume ratios in insects

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Insect Science 2017年第5期24卷 829-841页

作者： Sara Kuhsel Adrian Bruckner sebastian Schmelzle Michael Heethoff Nico Bluthgen Department of Biology Technische Universitat Darmstadt Schnittspahnstrasse 3 D-64287 Darmstadt Germany

Body mass, volume and surface area are important for many aspects of the physiology and performance of species. Whereas body mass scaling received a lot of attention in the literature, surface areas of animals have not been measured explicitly in this context. We quantified surface area-volume （SA/V） ratios for the first time using 3D surface models based on a structured light scanning method for 126 species of pollinating insects from 4 orders （Diptera, Hymenoptera, Lepidoptera, and Coleoptera）. Water loss of 67 species was measured gravimetrically at very dry conditions for 2 h at 15 and 30 ℃ to demonstrate the applicability of the new 3D surface measurements and relevance for predicting the performance of insects. Quantified SA/V ratios significantly explained the variation in water loss across species, both directly or after accounting for isometric scaling （residuals of the SA/V - mass2/3 relationship）. Small insects with a proportionally larger surface area had the highest water loss rates. Surface scans of insects to quantify allometric SA/Vratios thus provide a promising method to predict physiological responses, improving the potential of body mass isometry alone that assume geometric similarity.

关键词： body size body shape 3D surface imaging sphericity structured light water loss

Effect of asymmetric rolling on mechanical characteristics,texture and misorientations in ferritic steel

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Journal of Central South University 2013年第6期20卷 1443-1455页

作者： Wrofiski sebastian Wierzbanowski Krzysztof Bacroix Brigitte Chauveau Thierry Wrobel Mirostaw AGH University of Science and Technology Faculty of Physics and Applied Computer Science Krak6w 30-059 Poland LSPM-CNRS Universit6 Paris 13 Villetaneuse 93 430 France AGH University of Science and Technology Faculty of Metals Engineering and Industrial Computer Science Krak6w 30-059 Poland

The mechanical and microstructural properties as well as crystallographic textures of asymmetrically rolled low carbon steel were *** modelling of plastic deformation was carried out in two scales:in the macro-scale,using the finite elements method,and in the crystallographic scale,using the polycrystalline deformation *** internal stress distribution in the rolling gap was calculated using the finite elements method and these stresses were then applied to the polycrystalline elasto-plastic deformation *** mechanical properties,namely residual stress distribution,deformation work,applied force and torques,and bend amplitude,were *** diffraction measurements,X-ray and electron backscatter diffraction,enabled the examination of texture heterogeneity and selected microstructure *** predicted textures agree well with those determined *** plastic anisotropy of cold rolled ferritic steel samples,connected with texture,was expressed by Lankford coefficient.

关键词： asymmetric rolling crystallographic texture residual stress deformation model finite elements method diffraction