bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multivariate and geometric morphometrics in the analysis of sexual dimorphism variation in Podarcis lizards
Authors: Kaliontzopoulou Antigoni , Carretero Miguel A. , Llorente Gustavo A. 
Published: January 2007

AbstractPodarcis bocagei and P. carbonelli are two closely related lacertid species, very similar morphologically and ecologically. We investigated sexual dimorphism patterns presented by both species in allopatry and in sympatry. Sexual size and shape dimorphism patterns were analyzed using both multivariate and geometric morphometric techniques. Multivariate morphometrics revealed a marked sexual dimorphism in both species—males being larger with more robust habitus and females presenting a longer trunk. General patterns of sexual size dimorphism are not modified in sympatry, although there is evidence for some morphological change in male head size. The application of geometric morphometrics offered a more detailed image of head shape and revealed that males present a more developed tympanic area than do females, while females have a more rounded head. Differences in the degree of sexual shape dimorphism were detected in sympatry, but no consistent patterns were observed. From the results of the study, and based on previous knowledge on the populations studied, we conclude that the morphological differences observed are probably not caused by exploitative competition between the species, but rather appear attributable to the modification of the relative influence of sexual and natural selection on both sexes. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
Pisodonophis boro (ophichthidae: anguilliformes): Specialization for head‐first and tail‐first burrowing?
Authors: De Schepper Natalie , De Kegel Barbara , Adriaens Dominique 
Published: January 2007

AbstractThe rice paddy eel, Pisodonophis boro (P. boro), is of special interest because of its peculiar burrowing habits. P. boro penetrates the substrate tail‐first, a technique common for ophichthids, but it is able to burrow head‐first as well. P. boro exhibits three feeding modes: inertial feeding, grasping, and spinning. Rotational feeding is a highly specialized feeding mode, adopted by several elongate, aquatic vertebrates and it is likely that some morphological modifications are related to this feeding mode. The detailed morphology of the head and tail of P. boro is examined with the goal to apportion the anatomical specializations among head‐first burrowing, tail‐first burrowing, and rotational feeding. The reduced eyes, covered with thick corneas may be beneficial for protection during head‐first burrowing, but at the same time decreased visual acuity may have an impact on other sensory systems (e.g. cephalic lateral line system). The elongated and pointed shape of the skull is beneficial for substrate penetration. The cranial bones and their joints, which are fortified, are advantageous for resisting high mechanical loads during head‐first burrowing. The aponeurotic connection between epaxial and jaw muscles is considered beneficial for transferring these forces from the body to the head during rotational feeding. Hypertrophied jaw muscles facilitate a powerful bite, which is required to hold prey during spinning movements and variability in the fiber angles of subdivisions of jaw muscles may be beneficial for preventing the lower jaw from being dislodged or opened. Furthermore, firm upper (premaxillo–ethmovomerine complex) and lower jaws (with robust coronoid processes) and high neurocranial rigidity are advantageous for a solid grip to hold prey during rotational feeding. The pointed shape of the tail and the consolidated caudal skeleton are beneficial for their tail‐first burrowing habits. It is quite likely that the reduction of the caudal musculature is related to the tail‐first burrowing behavior because the subtle movements of the caudal fin rays are no longer required. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
The relationships of distributive justice and compensation system fairness to employee attitudes in international joint ventures
Authors: Choi Jaepil , Chen Chao C. 
Published: January 2007

AbstractEmployee perceptions of the fairness of general corporate systems have thus far not received enough attention in the organizational justice literature. To fill this gap, we examined perceptions of the fairness of the compensation systems of international joint ventures in China. It is argued that perceptions of compensation system fairness are positively related to the three distributive justice dimensions, i.e., performance‐based distributive justice, comparative distributive justice relative to foreign expatriates, and comparative distributive justice relative to local colleagues. Perceptions of compensation system fairness are also hypothesized to mediate the relationships between the three distributive justice dimensions and organizational commitment and turnover intention. A survey of 161 Chinese employees in Sino‐foreign joint ventures found a positive relationship between perceptions of distributive justice and perceptions of compensation system fairness. In particular, compensation system fairness was more strongly associated with performance‐based distributive justice than with the other two distributive justice dimensions based on social comparison. The mediating role of compensation system fairness was strongly supported. Copyright © 2007 John Wiley & Sons, Ltd.
Measuring the quality of hospitality at Antalya
Authors: Davutyan Nurhan 
Published: January 2007

AbstractTourism has become an important pillar of the Turkish economy. Therefore, service quality of the catering sector deserves and attracts attention. This paper employs data envelopment analysis (DEA), a linear programming method, to gauge the validity of official quality ratings at Antalya, a major seaside resort. This benchmarking‐based technique is applied to standardise the ‘starring’ system used by regulators and rating agencies. This is done by using efficiency scores generated by the DEA technique. Such standardisation helps tourists and tour operators. In addition, a second‐stage Tobit regression identifies the causes of inefficiency, and the managerial implications of the findings are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Rationalising terror‐related risks: the case of Israeli tourists in Sinai
Authors: Uriely Natan , Maoz Darya , Reichel Arie 
Published: January 2007

AbstractResearch into tourist reactions to terror requires qualitative studies that provide insight into the affective and cognitive processes that tourists experience when facing terror‐related risks. The study responds to this need by focusing on Israeli tourists who voluntarily travelled to the terror‐threatened destination of Sinai, Egypt. Applying ethnographic methods, the study identifies two major rationalisations tourists used to reduce their perceived risk: (i) inward‐oriented rationalisations that reduce the perceived risk of the destination by stressing the safety within it; and (ii) outward‐oriented rationalisations that reduce the perceived risk of the destination by emphasising the terror‐related risks, which exist elsewhere. Copyright © 2007 John Wiley & Sons, Ltd.
Marketing visitor attractions: a segmentation study
Authors: Litvin Stephen W. 
Published: January 2007

AbstractThis research revisits issues related to the travel behaviours of first‐time versus repeat visitors to a destination, with a special focus on the impact that the repeat visitor segment has upon the paid‐attraction sector. Healthy attractions are critically important to the success of a destination, but as this research notes, attractions have difficulty drawing guests in a repeat visitors‐dominated market. Implications that should be of value to marketers and attraction management in any maturing tourism destination are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Contrasting approaches of corporate and association meeting planners: how the hospitality industry should approach them differently
Authors: Toh Rex S. , Peterson Dean , Foster T. Noble 
Published: January 2007

AbstractUsing survey data, this paper examines the different goals and constraints facing corporate and association meeting planners (AMPs). It next shows how these differences produce 11 different concerns and behaviours. For instance, increased pressure for ethical behaviour and financial transparency has forced corporate meeting planners to focus attention on reducing meeting costs and to choose easily accessible and convenient properties for meetings. On the other hand, associations focus on the interests of their members and strive to comport with group norms, and therefore plan enjoyable family‐friendly meetings, often at relaxed and upscale locations. This paper outlines seven different ways in which the hospitality industry should approach corporate and AMPs. Copyright © 2007 John Wiley & Sons, Ltd.
Theoretische und praktische Betrachtungen zur Abscheidung verschiedener Schichttypen am Beispiel von galvanisch Nickel
Authors: Lampke T. , Steinhäuser S. , Richter D. , Wielage B. 
Published: January 2007

AbstractGalvanisch abgeschiedene Metalle weisen in Abhängigkeit von Metallsalzkonzentration, Stromdichte, pH‐Wert, Art und Menge organischer Zusätze, Badtemperatur, äußerer Konvektion, Substrateigenschaften und Charakter des abgeschiedenen Metalls unterschiedliche Wachstumstypen auf. Durch Parametervariation werden in Abhängigkeit vom Schichttyp Änderungen in den Schichteigenschaften erwartet. Zur Vertiefung des Verständnisses bzgl. der Struktur‐Eigenschaftsbeziehungen wurde die Wirkung wesentlicher Abscheidungsparameter, wie Stromdichte, Elektrolytkonzentration und organische Zusätze auf Schichttyp, Textur, Härte und Korrosionsverhalten am Beispiel von Watts Nickel Schichten untersucht. Nur durch Kombination mehrerer Zusätze konnten feinere Kristallite mit Übergängen vom FT‐Typ zu UD‐Formen und damit Härtesteigerungen um bis zu 200 % im Vergleich zu zusatzfreien Elektrolyten erreicht werden. Die verwendeten organischen Zusätze führen jedoch häufig zu einer Verschlechterung des Korrosionsverhaltens. Durch Variation der Stromdichte wurde bei Watts Nickel keine signifikante Änderung des Schichttyps registriert. Bei höherer Stromdichte wurde eine Zunahme von Härte und Korrosionswiderstand festgestellt.
Untersuchung des Einflusses von Prozessparametern in der Fertigstrasse auf die Tertiärzunderausbildung
Authors: Kawalla R. , Steinert F. 
Published: January 2007

AbstractIm Zuge des permanenten Bestrebens nach einer kostengünstigen Herstellung von Flachprodukten aus Stahl sowie durch den technischen Fortschritt im Bereich der Anlagentechnik, liegt ein aktueller Entwicklungstrend darin, kaltgewalzte Produkte durch warmgewalzte Produkte zu substituieren. Vorraussetzung dafür ist die Beherrschung und systematische Steuerung der bei der Warmbanderzeugung auftretenden unvermeidbaren Oxidationsvorgänge. Über die Einstellung entsprechender Oxidschichteigenschaften auf Warmbändern bei gleichzeitig geforderten mechanischen Eigenschaften, würde sich die Möglichkeit eröffnen, Warmband direkt weiterzuverarbeiten und damit die sehr kostenintensiven und wenig umweltfreundlichen Prozessschritte des Beizens, Kaltwalzens und Glühens einzusparen. Das gegenwärtige Wissen über den Einfluss von Prozessbedingungen beim Warmwalzen auf die Eigenschaften von Tertiärzunder, insbesondere Dicke, Zusammensetzung und Haftfestigkeit ist noch lückenhaft. Daher werden in diesem Beitrag Einflüsse auf die Oxidation bzw. die Zundereigenschaften während des Warmwalzprozesses beginnend von der Fertigstrasse bis zum Haspeln basierend auf Ergebnissen von Laboruntersuchungen zur Simulation von wesentlichen Prozessparametern in der Fertigstrasse diskutiert.
Evaluation of braze materials used for automotive liquid hydrogen tanks with special respect to hydrogen embrittlement and low temperature toughness
Authors: Michler T. , Naumann J. , Leistner W. 
Published: January 2007

AbstractCopper (CU 104 and CW021A), Nickel (NI 102 and MBF51) and Silver (AG102) braze joints with stainless steel 1.4401/1.4404 were investigated with respect to hydrogen embrittlement and cryogenic toughness.CW021A and MBF51 with different braze thicknesses and temperatures were Charpy V tested at 20 °C and ‐196 °C. Neither the seam thickness nor the test temperature had a significant influence on the Charpy V toughness. All toughness values were below 15 J/cm2. The reason is the low thickness of the braze seam and therefore the low volume of deformable material.CU 104, CW021A, NI 102, MBF51 and AG102 braze joints were tensile tested in hydrogen of different pressures and temperatures. Neither of the soldering showed any kind of hydrogen embrittlement.
Light‐weight design chances using high‐strength steels
Authors: Sonsino C. M. 
Published: January 2007

AbstractIn order to make effective use of high‐strength steels for designing light‐weight structures, it is necessary to consider the interaction between the service loading, material, geometry and manufacturing technology. This interaction determines durability. The fatigue performance of high‐strength steels can be better exploited if high stress concentrations are reduced through geometry improvement and manufacturing process control. With regard to their capability for high energy absorption, high‐strength steels offer the best solutions for designing against impact loads and crash. These advantages of high‐strength steels are realised in modern vehicle structures through the multi‐material concept, where materials selection is made according to expected service loads and locally required strengths.
The epidermal growth factor receptor and human topoisomerases represent potential cellular targets of oligomeric procyanidins
Authors: Fridrich Diana , Kern Melanie , Fritz Jessica , Pahlke Gudrun , Köhler Nils , Winterhalter Peter , Marko Doris 
Published: January 2007

AbstractOligomeric procyanidins were found to inhibit the protein tyrosine kinase activity of the epidermal growth factor receptor (EGFR). The inhibitory potency was found to increase with the degree of oligomerisation (PA2 > PC1 >> PB1 = PB2 = PB3 = PB4 >> (–)‐epicatechin). To address the question whether the interference with the activity of isolated EGFR preparations also plays a role within intact cells, effects on the phosphorylation status of the EGFR, as a measure of its activity, were determined in human colon carcinoma cells. Treatment of HT29 cells with the trimeric procyanidin PC1 resulted in a decrease of the EGFR autophosphorylation already at low micromolar concentrations. A respective procyanidin tetramer (PA2) failed to affect substantially the receptor phosphorylation status by up to 50 μM, indicating that the effectiveness of oligomeric procyanidins against EGFR activity within intact cells might be limited with increasing degree of polymerisation. Nevertheless, oligomeric procyanidins were identified as potential inhibitors of the EGFR, which might be of interest with respect to chemoprevention. However, PC1 and PA2 were also identified as potent inhibitors of the catalytic activity of human topoisomerase I and II, demanding further studies to elucidate whether the interference of procyanidins with topoisomerases might impair DNA integrity, thus limiting their usefulness in terms of chemoprevention.
Transversely isotropic membrane shells with application to mitral valve mechanics. Constitutive modelling and finite element implementation
Authors: Prot V. , Skallerud B. , Holzapfel G. A. 
Published: January 2007

AbstractThe present study addresses constitutive modelling and implementation of transversely isotropic hyper‐elastic material models for the analysis of the mitral valve. This valve separates the left atrium and left ventricle in the heart. Two convex strain energy potentials are employed in derivation of stress tensors and elasticity tensors. The plane stress and incompressibility conditions are accounted for directly. The relationships are implemented in an implicit code (ABAQUS) via the user‐defined interface. Numerical simulations of the valve motion during a part of the heart cycle are carried out and compared to ultrasound measurements of a healthy human valve. The significance of placement of chordae tendinae is illustrated. The implementation provides a tool for simulations of both healthy and pathological mitral valve conditions. Copyright © 2007 John Wiley & Sons, Ltd.
Experimental and theoretical investigation of PLC bands
Authors: Feng X. , Crostack H.‐A. , Fischer G. , Svendsen B. 
Published: January 2007

AbstractIn this paper, the nucleation and propagation of PLC deformation bands in AlMg3 alloy are studied experimentally and theoretically. The morphology and kinematics of PLC bands are investigated using both mechanical and thermal measurement methods. In particular, the latter is based on the use of a thermal camera which captures the temperature changes resulting from mechanical dissipation during nucleation and propagation of PLC bands. On the modeling side, two models are investigated via finite‐element and finite‐difference methods. Here, attention is focused on the influence of the specimen geometry and the thermomechanical coupling on PLC band nucleation and propagation. A comparison of experimental and simulation results is presented. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Coupled Finite Thermoviscoplasticity of Glassy Polymers
Authors: Göktepe Serdar , Miehe Christian 
Published: January 2007

AbstractThe contribution is concerned with the constitutive modeling of the temperature and thermomechanical coupling effects on the rate–dependent finite plastic behavior of glassy polymers. In contrast to the existing kinematic approaches to the finite plasticity of glassy polymers, we propose a distinct kinematic framework constructed in the logarithmic strain space [5]. The logarithmic framework is extremely attractive due to the fact that it allows a very efficient algorithmic treatment of finite plasticity akin to the geometrically linear theory. The evolution law of plastic strains is adopted from Argon's double kink theory [1, 3]. Temperature–induced softening is incorporated by thermal disassociation of the secondary bonds in the polymer network [6, 2]. In the FE analysis of the coupled BVPs, the staggered scheme is employed [7]. The proposed formulation is validated by simulating various experimental data. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
ALE‐based 3D FE simulation of electromagnetic forming
Authors: Stiemer Marcus , Unger Jaan , Blum Heribert , Svendsen Bob 
Published: January 2007

AbstractElectromagnetic forming is a contact‐free high‐speed forming process. The deformation of the work piece is driven by the Lorentz force which results from the interaction of a pulsed magnetic field with eddy currents induced in the work piece by the field itself. The purpose of this work is to present a fully‐coupled three‐dimensional simulation of this process. For the mechanical structure, a thermoelastic, viscoplastic, electromagnetic material model is relevant, which is incorporated in a large‐deformation dynamic formulation. The electromagnetic fields are governed by Maxwell's equations under quasistatic conditions. To consider their reduced regularity at material interfaces Nédélec elements are applied. Coupling takes the form of the Lorentz force, the electromotive intensity and the current geometry of the work piece. A staggered solution scheme based on a Lagrangian mesh for the work piece and an ALE formulation for the electromagnetic field is employed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Homogenization of fibre composites using X‐FEM
Authors: Kästner Markus , Ulbricht Volker 
Published: January 2007

AbstractA successful material design process for novel textile reinforced composites requires an integrated simulation of the material behaviour and the estimation of the effective properties used in a macroscopic structural analysis. In this context the Extended Finite Element Method (X‐FEM) is used to model the behavior of materials that show a complex structure on the mesoscale efficiently. A homogenization technique is applied to compute effective macroscopic stiffness parameters. This contribution gives an outline of the implementation of the X‐FEM for complex multi‐material structures. A modelling procedure is presented that allows for the automated generation of an extended finite element model for a specific representative volume element. Furthermore, the problem of branching material interfaces arising from complex textile reinforcement architectures in combination with high fibre volume fractions will be addressed and an appropriate solution is proposed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energetic modelling for carbon fibre reinforced carbon
Authors: Langhoff T.‐A. , Schnack Eckart 
Published: January 2007

AbstractIn this contribution an energetic model for multi‐phase materials is developed describing the influence of microstructure on different length scales as well as the evolution of phase changes. Restrictions on the energy functional are discussed. In such a non‐convex framework, interfacial contributions serve for relaxing the total energy. Such models can be applied to describe the macroscopic material properties of carbon fibre reinforced carbon where phase transitions between regions of different texture of the carbon matrix are observed on nanoscale as well as columnar microstructures on microscale [2]. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Integration of infinite chain of transport equations for cumulants
Authors: Grebenev V. N. , Oberlack M. 
Published: January 2007

AbstractThe method of compatible differential constraints is applied to integrate an infinite chain of transport equations for cumulants. The dynamics of a stratified momentumless turbulent planar wake is considered as an example. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of mass loading on particle‐laden turbulent channel flow
Authors: Kubik A. , Kleiser L. 
Published: January 2007

AbstractResults are presented for the behavior of particle‐laden gases in a moderate Reynolds number vertical channel down flow. The effects of mass loading on the gas‐phase turbulence and particle concentration are studied. A direct numerical simulation including models of wall‐particle interaction is conducted. It is confirmed that particle feedback causes the turbulence intensities to become more non‐isotropic as the particle loading is increased. The particle concentration exhibits a maximum close to the wall and a slight increase in the middle of the channel. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mathematical Force Concept for the One‐Way‐Coupling of Dynamic Fibers and Turbulent Flows
Authors: Marheineke Nicole , Wegener Raimund 
Published: January 2007

AbstractFor the modeling of turbulence effects on the dynamics of a long slender elastic fiber, a mathematical aerodynamic force concept is presented in this work. It yields a correlated random Gaussian force and respectively uncorrelated Gaussian white noise with flow‐dependent amplitude in the asymptotic limit on the macroscopic fiber scale. Numerical comparisons of the correlated and uncorrelated force effects on the fiber behavior show coinciding results. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerische Analyse eines Flotationsprozesses
Authors: Streng Mario , Wünsch Olaf 
Published: January 2007

AbstractDie turbulente, einphasige Strömung in einem Flotationssegment wird mit einem numerischen Verfahren stationär bzw. instationär berechnet und anhand ausgewählter Konturplots für das Geschwindigkeits‐ und Druckfeld analysiert und verglichen. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)