bluuebunny/crossref_metadata_2025 huggingface dataset:
Pisodonophis boro (ophichthidae: anguilliformes): Specialization for head‐first and tail‐first burrowing?
Authors: De Schepper Natalie , De Kegel Barbara , Adriaens Dominique
Published: January 2007

The 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

Employee 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

Tourism 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

Research 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

This 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

Using 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

Galvanisch 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

Im 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

Copper (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

In 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

Oligomeric 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

The 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

In 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

The 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

Electromagnetic 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

A 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

In 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

The 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

Results 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

For 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

Die 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)
Longitudinal and transversal two‐point correlations in a turbulent flow
Authors: Stresing Robert , Barth Stephan , Peinke Joachim
Published: January 2007

Based on measurements with hot‐wire anemometers in a fully developed turbulent flow in the wake of a cylinder we investigate different aspects of longitudinal and transversal two‐point correlations. In particular we use Taylor's hypothesis as well as simultaneous measurements with two X‐hot‐wire probes, and investigate how these correlations change with the relative orientation of their separation vector with respect to the mean flow direction. For the wake at a distance of eighty cylinder diameters at a Reynolds number Re = 28 000 (Taylor‐based Reynolds number Reλ = 290), we find evidence of strong anisotropy. We analyze the data using increment statistics, in particular increment distributions and structure functions. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
DNS of a Turbulent Channel Flow with Streamwise Rotation ‐ Study of the Reverse Effect of the Cross Flow
Authors: Weller Tanja , Oberlack Martin
Published: January 2007

Modeling of rotating turbulent flows is a major issue in engineering applications. In this work a turbulent channel flow rotating about the streamwise direction is presented. The theory is based on the investigations of [3] employing Lie group analysis. It was found that a cross flow in spanwise direction is induced. A series of direct numerical simulations (DNS) has been conducted for both different rotation rates and different Reynolds numbers to validate the cross flow. In addition some new interesting effects were observed. The averaged profile ū3 of the cross flow is formed like a ‘S’ that means it exhibits a triple zero‐crossing which denotes regions of reverse flow. Alaso a reverse effect is seen which means that for small rotation rates up to Ro=10 the spanwise mean velocity profiles increase and at rotation number Ro=14 this effect appears to reverse. Both effects were observed at two different Reynolds numbers Re = 180 and Re = 270. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
3D simulations and experiments of flow in a folded microchannel
Authors: Barz Dominik P. J. , Farengis Zadeh Hamid , Ehrhard Peter
Published: January 2007

We investigate the three–dimensional pressure–driven flow field in a folded microchannel. Experiments and numerical simulations are performed. A method termed “partial particle tracking”, resulting in partial velocity profiles, indicates that secondary flows exist. The comparison of numerical and experimental partial velocity fields shows good agreement. The existence of secondary flow results from centrifugal forces due to the curved channel geometry. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Untersuchung eines scherverdünnenden Fluids im Zylinderspalt
Authors: Smieszek M. , Egbers C.
Published: January 2007

Es wird das Strömungsverhalten eines viskoelastisches, scherverdünnendes Fluid imTaylor‐Couette‐Systemuntersucht. Zusätzlich werden Vergleichsmessungen mit einem Newtonschen Fluid durchgeführt. Die bestimmten kritischen Übergänge werden als Funktion der Reynoldszahl in Stabilitätsdiagrammen aufgetragen. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Insulin‐like growth factor binding protein‐related protein 1 (IGFBP‐rP1) has potential tumour‐suppressive activity in human lung cancer
Authors: Chen Y , Pacyna‐Gengelbach M , Ye F , Knösel T , Lund P , Deutschmann N , Schlüns K , Kotb WFMA , Sers C , Yasumoto H , Usui T , Petersen I
Published: January 2007

The expression of insulin‐like growth factor binding protein‐related protein 1 (IGFBP‐rP1) is decreased in various tumours, but the role of IGFBP‐rP1 in lung cancer is not yet clear. In this study, IGFBP‐rP1 expression in lung cancer cell lines was evaluated and reduced expression of IGFBP‐rP1 was found. In tissue microarrays containing 138 primary tumours and 20 normal lung tissues analysed by immunohistochemistry, 58 tumours (42%) exhibited no expression of IGFBP‐rP1, while all 20 normal lung tissues showed high expression. In squamous cell lung cancer, low expression of IGFBP‐rP1 was significantly linked to high‐grade tumours. Treatment with 5‐aza‐2′‐deoxycytidine restored the expression of IGFBP‐rP1 in three of four lung cancer cell lines. Sequencing of PCR products of sodium bisulphite‐treated genomic DNA from the three lung cancer cell lines revealed a heterogeneous methylation pattern in the region of exon 1 and intron 1. Stable transfection of IGFBP‐rP1 full‐length cDNA into the H2170 lung cancer cell line led to increased expression of IGFBP‐rP1 protein. IGFBP‐rP1‐positive transfectants exhibited remarkably reduced colony‐forming ability in soft agar, suppression of tumour growth rate in nude mice, and increased apoptotic cell number as well as activated caspase‐3 expression level. The data suggest that IGFBP‐rP1 is a tumour suppressor inactivated by DNA methylation in human lung cancer. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
1,3‐dichlorotetra‐n‐butyldistannoxane as a novel ATRP initiator: Property, catalysis ability, and mechanism
Authors: Xu Zhi , Yin Shougen , Lei Bin , Lu Yan , Chang Weixing , Li Jing
Published: January 2007

1,3‐dichloro‐tetra‐n‐butyl‐distannoxane, which contains SnCl bonds, was used as a novel initiator for atom transfer radical polymerization of styrene in bulk. Some interesting results that were thought to be related to the characteristics of the 1,3‐dihalotetra‐alkyl‐distannoxanes had been obtained. The concentration of the 1,3‐dichlorotetra‐n‐butyl‐distannoxane in the bulk solution of styrene was confirmed to be an important factor for the different results of the polymerization. The corrected theoretical molecular weights, which were based on the proposed mechanism, accorded with the GPC results very well. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 942–948, 2007
Functionalization of iron oxide magnetic nanoparticles with poly(methyl methacrylate) brushes via grafting‐from atom transfer radical polymerization
Authors: Garcia I. , Zafeiropoulos N. E. , Janke A. , Tercjak A. , Eceiza A. , Stamm M. , Mondragon I.
Published: January 2007

A key problem with nanomaterials is the difficulty of controlling the dispersion of nanoparticles inside an organic medium. To overcome this problem, functionalization of the nanoparticle surface is required. Poly(methyl methacrylate) (PMMA) brushes were grown on the surface of iron oxide magnetic nanoparticles with atom transfer radical polymerization and a grafting‐from approach. Modified magnetic nanoparticles with a graft density of 0.1 PMMA chains/nm2 were obtained. Cu(II), used as a deactivating complex, allowed good control of the polymerization along with a narrow polydispersity of the polymer chains. The functionalized magnetic nanoparticles were characterized with Fourier transform infrared spectroscopy, thermogravimetric analysis, gel permeation chromatography, and atomic force microscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 925–932, 2007
Antiplasmodial activity of Setaria megaphylla
Authors: Okokon Jude E. , Ubulom Peace M. E. , Udokpoh Aniekan E.
Published: January 2007

The antimalarial activity of an ethanol leaf extract of Setaria megaphylla was studied in vivo in mice infected with Plasmodium berghei berghei during early and established infections. Setaria megaphylla (100–300 mg/kg/day) exhibited a significant (p < 0.05) blood schizonticidal activity in 4‐day early infection and in established infection with a significant (p < 0.05) mean survival time comparable to that of the standard drug, chloroquine, 5 mg/kg/day. The leaf extract possesses a promising antiplasmodial activity in vivo which can be exploited in malaria therapy. Copyright © 2007 John Wiley & Sons, Ltd.
Ursolic acid plays a role in Nepeta sibthorpii Bentham CNS depressing effects
Authors: Taviano M. F. , Miceli N. , Monforte M. T. , Tzakou O. , Galati E. M.
Published: January 2007

The sedative, anticonvulsant and analgesic activity of ursolic acid, a terpenoid bioassay‐isolated from Nepeta sibthorpii Bentham, was evaluated in mice. The oral administration of ursolic acid (2.3 mg/kg) produced a significant depressant effect on CNS by reducing spontaneous motor activity and the number and lethality of pentylenetetrazol (PTZ)‐induced seizures. Two models of nociception, the writhing test and the hot plate test, were also used to examine the analgesic effect of ursolic acid. At a dose of 2.3 mg/kg, ursolic acid caused an inhibition of acetic acid‐induced abdominal constriction, but was inactive in the hot plate test. Treatment at a higher dose (20 mg/kg) significantly increased the reaction time in the hot plate test. This effect, reversed by naloxone, evidently involves opioid receptors, but the analgesic activity of ursolic acid may be related also to the antiinflammatory and antioxidant properties of this compound. Copyright © 2007 John Wiley & Sons, Ltd.
In vitro activities of Citrus medica L. cv. Diamante (Diamante citron) relevant to treatment of diabetes and Alzheimer's disease
Authors: Conforti Filomena , Statti Giancarlo Antonio , Tundis Rosa , Loizzo Monica Rosa , Menichini Francesco
Published: January 2007

The present study showed for the first time the in vitro properties (antioxidant, hypoglycaemic and anticholinesterase) of Citrus medica L. cv. Diamante which belongs to the Rutaceae family. The n‐hexane extract of Diamante citron peel is characterized by the presence of monoterpenes and sesquiterpenes. The most abundant constituents were two monoterpenes: limonene and γ‐terpinene. The extract showed significant antioxidant activity that was carried out using different assays (DPPH test, β‐carotene bleaching test and bovine brain peroxidation assay). Oxidative damage, caused by the action of free radicals, may initiate and promote the progression of a number of chronic diseases, including diabetes and Alzheimer's disease. Diamante citron peel extract showed hypoglycaemic activity and an anticholinesterase effect. Copyright © 2007 John Wiley & Sons, Ltd.
Extract of Hypericum perforatum blocks caffeine‐induced locomotor activity in mice: a possible role of nitric oxide
Authors: Uzbay I. Tayfun , Coskun Ilke , Kayir Hakan , Ozturk Nilgun , Ozturk Yusuf
Published: January 2007

The present study investigated the effects of HPE on caffeine‐induced locomotor activity in mice. Caffeine (4–16 mg/kg) or saline were given to adult male Swiss‐Webster mice, and the locomotor activity was immediately measured for 30 min. HPE (6–48 mg/kg) and saline were injected to another group of mice and the locomotor activity was measured 20 min later. HPE (6–24 mg/kg) was also administered to another group of mice 20 min before caffeine (16 mg/kg) injections and the locomotor activity was recorded for 30 min immediately after caffeine administrations. Finally l‐arginine (1 g/kg) was administered i.p. 20 min before HPE (6 mg/kg) and the locomotor activity was measured as mentioned above. Each group of mice was used only once. Caffeine produced some significant increases in locomotor activity of the mice. HPE (6–24 mg/kg) significantly blocked the caffeine‐induced locomotor hyperactivity. Pretreatment of l‐arginine (1 g/kg) reversed the inhibitory effect of HPE (6 mg/kg) on caffeine‐induced locomotor activity without producing any significant effect on locomotor activity of the mice when it was administered alone. The results suggest that HPE blocks caffeine‐induced locomotor hyperactivity in mice. Furthermore, the inhibitory effect of HPE on caffeine‐induced locomotor activity may be related to its NOS inhibitory property. Copyright © 2007 John Wiley & Sons, Ltd.
In Vitro antimycotic activity of xanthorrhizol isolated from Curcuma xanthorrhiza Roxb. against opportunistic filamentous fungi
Authors: Rukayadi Yaya , Hwang Jae‐Kwan
Published: January 2007

Xanthorrhizol was isolated from the rhizome of Curcuma xanthorrhiza (Zingiberaceae) and its in vitro activity against opportunistic filamentous fungi was evaluated using the NCCLS (M38‐A) standard method. Xanthorrhizol was found to be active against all the species tested, namely Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Fusarium oxysporum, Rhizopus oryzae and Trichophyton mentagrophytes: the MICs being 2.0, 2.0, 2.0, 4.0, 1.0 and 1.0 µg/mL, while the MFCs were 4.0, 4.0, 4.0, 8.0, 2.0 and 2.0 µg/mL, respectively. The susceptibility of six species of filamentous fungi to xanthorrhizol was comparable to that of the commercial antifungal, amphotericin B. Xanthorrhizol also has activity to inhibit the conidial germination of all tested species. The results strongly suggest that xanthorrhizol can be developed as a natural antifungal agent. Copyright © 2007 John Wiley & Sons, Ltd.
Concern Regarding the Synthesis of Single‐Crystalline Nanostructures from the Polymerization of Furfuryl Alcohol
Authors: Zhao Dongyuan , Yan Yan , Tu Bo , Yang Haifeng
Published: January 2007

In response to the concerns of Prof. Gandini, the authors of the manuscript “Surfactant‐Templated Synthesis of 1D Single‐Crystalline Polymer Nanostructures” discuss their results and put them into context (with the assistance of further characterization) with other literature surrounding the polymerization of furfuryl alcohol.
Dissociation between apoptosis, neurogenesis, and synaptic potentiation in the dentate gyrus of adrenalectomized rats
Authors: Krugers H.J. , van der Linden S. , van Olst E. , Alfarez D.N. , Maslam S. , Lucassen P.J. , Joëls M.
Published: January 2007

Removal of adrenal hormone corticosterone in rats aged 3–4 months results within 3 days in acceleration of apoptosis and proliferation of newborn cells in the dentate gyrus (DG). A critical question is whether such a shift in the maturity of dentate cells after adrenalectomy (ADX) affects synaptic plasticity. To address this question, male rats were adrenalectomized and synaptic potentiation was recorded in vitro in hippocampal slices, as well as in vivo, in response to high frequency stimulation of the perforant path, 3 days after ADX. At this time‐point, cell loss was assessed and proliferation was examined. Based on two independent parameters, bromodeoxyuridine and Ki‐67, we found that removal of the adrenal glands increases proliferation rate. This increase in proliferation was, in particular, evident in those animals that displayed substantial cell loss. The accelerated cell‐turnover after ADX was accompanied by reduced synaptic potentiation, both when recorded in vitro and in vivo. Corticosterone replacement in vivo (in adrenalectomized animals), at levels that activate the mineralocorticoid receptor, prevented ADX‐induced proliferation, apoptosis, and restored synaptic potentiation to control levels. Importantly, corticosterone applied to slices from adrenalectomized rats also normalized synaptic potentiation, despite increased proliferation. This suggests that changes in cell proliferation and apoptotic cell death in the DG are not necessarily key factors determining the efficacy of synaptic potentiation. Synapse 61:221–230, 2007. © 2007 Wiley‐Liss, Inc.
Agonist‐dependent internalization of D2 receptors: Imaging quantification by confocal microscopy
Authors: Goggi Julian L. , Sardini Alessandro , Egerton Alice , Strange Philip G. , Grasby Paul M.
Published: January 2007

In positron emission tomography and single photon emission computed tomography studies using D2 dopamine (DA) receptor radiotracers, a decrease in radiotracer binding potential (BP) is usually interpreted in terms of increased competition with synaptic DA. However, some data suggest that this signal may also reflect agonist (DA)‐induced increases in D2 receptor (D2R) internalization, a process which would presumably also decrease the population of receptors available for binding to hydrophilic radioligands. To advance interpretation of alterations in D2 radiotracer BP, direct methods of assessment of D2R internalization are required. Here, we describe a confocal microscopy‐based approach for the quantification of agonist‐dependent receptor internalization. The method relies upon double‐labeling of the receptors with antibodies directed against intracellular as well as extracellular epitopes. Following agonist stimulation, DA D2R internalization was quantified by differentiating, in optical cell sections, the signal due to the staining of the extracellular from intracellular epitopes of D2Rs. Receptor internalization was increased in the presence of the D2 agonists DA and bromocriptine, but not the D1 agonist SKF38393. Pretreatment with either the D2 antagonist sulpiride, or inhibitors of internalization (phenylarsine oxide and high molarity sucrose), blocked D2‐agonist induced receptor internalization, thus validating this method in vitro. This approach therefore provides a direct and streamlined methodology for investigating the pharmacological and mechanistic aspects of D2R internalization, and should inform the interpretation of results from in vivo receptor imaging studies. Synapse 61:231–241, 2007. © 2007 Wiley‐Liss, Inc.
PET imaging of neurokinin‐1 receptors with [18F]SPA‐RQ in human subjects: Assessment of reference tissue models and their test–retest reproducibility
Authors: Yasuno Fumihiko , Sanabria Sandra M. , Burns Donald , Hargreaves Richard J. , Ghose Subroto , Ichise Masanori , Chin Frederick T. , Morse Cheryl L. , Pike Victor W. , Innis Robert B.
Published: January 2007

[18F]SPA‐RQ (substance P antagonist receptor quantifier) labels the substance P‐preferring (NK1) receptor in human brain. A prior study showed that [18F]SPA‐RQ brain uptake can be quantified with a reference tissue method and thereby avoid invasive blood sampling. The purposes of this study were to compare three different reference tissue methods and to assess test–retest reproducibility. Eight healthy subjects underwent two [18F]SPA‐RQ scans. We calculated the binding potential (BP), which is proportional to receptor density, from both regional volume of interest and voxel‐wise data. We compared three reference tissue methods: simplified reference tissue model, multilinear reference tissue model (MRTM), and its two‐parameter version (MRTM2). The three methods generated equivalent values of regional BP, but MRTM2 was the most resistant to noise. Temporally stable values of BP were obtained with 240 min of imaging data. MRTM2 had excellent test–retest reproducibility, with high reliability (intraclass correlation > 0.9) and low variability (< 10%). In addition to regional volume of interest analysis, we also created parametric images of BP, variability, and reliability based on voxel‐wise time–activity data. The reproducibility of parametric BP was also good, with variability < 20% and reliability > 0.7 in gray matter regions. In conclusion, a two‐parameter reference tissue method (MRTM2) provided reproducible and reliable measurements of [18F]SPA‐RQ brain uptake using 240 min of both regional and voxel‐wise data. Synapse 61:242–251, 2007. Published 2007 Wiley‐Liss, Inc.
Signaling by hepatocyte growth factor in neurons is induced by pharmacological stimulation of synaptic activity
Authors: Tyndall Stephanie J. , Walikonis Randall S.
Published: January 2007

Activity‐dependent signaling by growth factors is hypothesized to link synaptic activity to structural and functional modifications of neurons. The receptor tyrosine kinase Met and its ligand, hepatocyte growth factor (HGF), are clustered at excitatory synapses and may regulate aspects of excitatory synaptic function, as HGF increases expression of excitatory synaptic proteins, enhances their clustering at sites along dendrites, and increases current through the NMDA receptor. In this article, we test for secretion or activation of HGF and for activation of Met in response to pharmacological stimulation of synaptic activity. Stimulation of dissociated hippocampal neuron cultures with glutamate caused increased immunocytochemical staining against HGF on nonpermeabilized cells. Glutamate treatment also decreased the amount of pro HGF and increased the amount of the proteolytically‐activated HGF in immunoblots of neuron culture lysates, and increased the levels of activated HGF in culture media. Stimulation of neuron cultures with glutamate or bicuculline induced autophosphorylation of Met on dendrites and the soma of neurons. Pretreatment of neurons with glutamate receptor inhibitors prior to glutamate treatment blocked autophosphorylation of Met. These results suggest that HGF can participate in activity‐dependent signaling in neurons. Synapse 61:199–204, 2007. © 2007 Wiley‐Liss, Inc.
Methamphetamine blood concentrations in human abusers: Application to pharmacokinetic modeling
Authors: Melega William P. , Cho Arthur K. , Harvey Dennis , Laćan Goran
Published: January 2007

Characterization of methamphetamine's (METH) dose‐dependent effects on brain neurochemistry may represent a critical component for better understanding the range of resultant behavioral pathologies. Most human studies, however, have assessed only the effects of long term, high dose METH abuse (e.g., greater than 1000 mg/day) in individuals meeting DSM‐IV criteria for METH dependence. Yet, for the majority of METH abusers, their patterns of METH exposure that consist of lower doses remain less well‐characterized. In this study, blood samples were obtained from 105 individuals detained by police for possible criminal activity and testing positive for stimulants by EMIT assay. METH blood concentrations were subsequently quantified by GC‐MS and were predominantly in the low micromolar range (0.1–11.1 μM), with median and mean values of 1.3 μM (0.19 mg/l) and 2 μM (0.3 mg/l), respectively. Pharmacokinetic calculations based on these measured values were used to estimate initial METH body burdens, the median value being 52 mg. Modeling a 52 mg dose for a 4 day–METH maintenance exposure pattern of 4 doses/day at 4 h intervals showed that blood concentrations remained between 1 and 4 μM during this period. Collectively, these data present evidence for a METH exposure pattern distinct from high dose‐METH abuse and provide the rationale for assessing potential brain pathology associated with such lower dose‐METH exposure. Synapse 61:216–220, 2007. © 2007 Wiley‐Liss, Inc.
A Systems Engineering Framework for Eco–Industrial Park Formation
Authors: Haskins Cecilia
Published: January 2007

Understanding eco‐industrial park formation requires a multidisciplinary viewpoint [Haskins, Syst Eng 9 (2006b)] that includes systems thinking, industrial ecology, organizational dynamics, logistics, and supply chain theory. The most often referenced eco‐industrial park found in Kalundborg, Denmark, serves as an ideal, and is typified by tight interdependency between industrial partners, green logistics, and closed‐loop supply chains. But the planet is in crisis [Atiyah and Press, joint statement from The Royal Society and the Hational Academy of Sciences on Population Growth and Sustainability, February 1992 ] and cannot afford to wait 30 years for more of these parks to emerge. Systems engineering has been found to be effective when bringing together stakeholders from diverse backgrounds and experts from multidisciplinary engineering and technical backgrounds to coordinate the creation of complex systems. This paper uses literature drawn from multidisciplinary sources to investigate the attributes of eco‐industrial parks, and then proposes a systems engineering framework, iFACE, for the formation of eco‐industrial parks. © 2007 Wiley Periodicals, Inc. Syst Eng 10: 83 –97, 2007.
The 160 N‐terminal residues of calnexin define a novel region supporting viability in Schizosaccharomyces pombe
Authors: Hajjar Fadi , Beauregard Pascale B. , Rokeach Luis A.
Published: January 2007

Protein secretion is a complex process that can be modulated by folding factors in the endoplasmic reticulum (ER), such as calnexin, a highly‐conserved molecular chaperone involved in quality control. In Schizosaccharomyces pombe, calnexin (Cnx1p) is essential for cell viability. The calnexin/Cnx1p determinants required for viability have been mapped within the last 123 residues of its C‐terminus. To better understand the role(s) of calnexin/Cnx1p in secretion, we screened for cnx1 mutants ‘super‐secreting’ cellulase. We identified ss14_cnx1, a mutant secreting 10‐fold higher levels of the glycoprotein cellulase than the wild‐type strain. While cellulase did not interact with ss14_Cnx1p, the ratio of secreted activity/quantity for this enzyme was not affected, suggesting that the quality control of folding in the ER was adequate in the mutant strain. Surprisingly, the ss14_Cnx1p mutant is composed of the 160 N‐terminal amino acids of the mature molecule, thus this mutant defines a novel calnexin/Cnx1p region supporting Sz. pombe viability. Interestingly, like viable mutants spanning the last 52 aa of calnexin/Cnx1p, the 160 N‐terminal residues encoded by ss14_cnx1 also forms a complex with the essential BiP chaperone. These results reveal the so far unidentified importance of the N‐terminal region of calnexin/Cnx1p. Copyright © 2007 John Wiley & Sons, Ltd.