bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation von Kohlenstoffnanoröhren mit Stone‐Wales Defekten
Authors: Ernst Gerald , Nasdala Lutz , Rothert Heinrich 
Published: December 2005

AbstractKraftfelder sind eine bewährte Methode für die Berechnung atomarer Strukturen wie Kohlenstoffnanoröhren. Die Bedeutung des Auftretens von Defekten für die mechanischen Eigenschaften der Kohlenstoffnanoröhren kann mit einem auf Kraftfeldern basierenden finiten Element nachgewiesen werden. Bei einer Belastung der Kohlenstoffnanoröhren kommt es in Abhängigkeit von der Last entweder zu Material‐ oder Stabilitätsversagen. Ein interessantes Ergebnis ist, dass bei Torsion Verzweigungsprobleme durch Defekte in Durchschlagsprobleme überführt werden. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelling of Mass Changes in Anisotropic Materials
Authors: Himpel Grieta , Kuhl Ellen , Menzel Andreas , Steinmann Paul 
Published: December 2005

AbstractFor the modelling of biomaterials with changing mass one can distinguish between a coupling of mass changes and deformations at the constitutive level, see e.g. [3], and a coupling at the kinematic level, see e.g. [4]. The constitutive coupling is typically realised by weighting the free energy function with the relative density. Such an ansatz enables the simulation of density changes and is generally used to model hard tissues. The kinematic coupling is characterised by a multiplicative split of the deformation gradient into an elastic part and a growth part. Such an ansatz enables the simulation of mass changes as changes in density and volume and is appropriate to model soft tissues. In this contribution the agreements and disagreements of both approaches should be presented by means of a transversely isotropic material and studied by numerical examples. For a more detailed description of the discussed topic, the reader is also referred to [2]. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A constitutive model for thermoplastic materials subjected to high strain rates
Authors: Kolling S. , Haufe A. 
Published: December 2005

AbstractReliable prediction of the behaviour of structures made from polymers is a topic under considerable investigation in engineering practice. Especially, if the structure is subjected to dynamic loading, constitutive models considering the mechanical behaviour properly are not available in commercial finite element codes yet. A constitutive model is derived including important phenomena like necking, strain rate dependency, unloading behaviour and damage. In particular, different yield surfaces in compression and tension and strain rate dependent failure, the latter with damage induced erosion, is taken into account. With the present formulation, standard verification tests can be simulated successfully. Also, an elastic damage model can be used to approximate the unloading behaviour of thermoplastics adequately. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multiscale Modeling of the Interphase Interactions in the Mechanics of Materials
Authors: Lurie Sergey , Volkov‐Bogorodsky Dmitrij , Tuchkova Natalia 
Published: December 2005

AbstractThe consistent and correct model of media taking into account scale effects (cohesion and adhesive interactions) is constructed as a special case of the Cosserat's pseudocontinuum model. The variant of the interphase layer theory is elaborated, which includes the following moments: formal mathematical statement, physical constitutive equations, numerical estimations of an interphase layer influence on the stress state and energy density distribution in a composite. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the physically motivated choice of internal variables describing martensitic phase transformations
Authors: Oberste‐Brandenburg Claus 
Published: December 2005

AbstractPhenomenological models which describe phase transformation in solids often employ a single scalar variable, the mass (or volume) fraction of one of the phases involved. However, the orientation of the applied stress has a major influence on the microstructure developing during the phase transition and thus the overall mechanical behavior. Therefore, additional internal variables of higher order have to be introduced in order to capture this aspect.The choice of these internal variables is often based on purely phenomenological considerations. In contrast to this, based on local observations at the phase boundary, a thermodynamically dual pair of second order tensors is introduced here.Constitutive relations for shape menory alloys in the pseudoelastic and pseudoplastic range are proposed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phase Transformation and Singularity Theory
Authors: Simon Werner 
Published: December 2005

AbstractPhase transformation plays an important role in thermodynamics and materials science. Based on the theory of singularities, a new method to construct phase diagrams is presented. Analysing singularities on base of root sequences, see Tamaschke [16], will help to develop singularity graphs, where workings by H. Whitney, R. Thom, and V. I. Arnold provide fundamentals. The generated singularity graphs build the starting point for singularity phase diagrams. A powerful characteristic of such singularity graphs is that higher‐dimensional surfaces can be transformed to a two‐dimensional diagram. The attained singularity diagram can be used in materials science for analytical models of temperature‐concentrated diagrams. As tools from algebra and analysis build a sound basis for singularity diagrams, it is possible to evolve computer software generating these phase diagrams. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Continua with affine microstructure: Theoretical aspects and applications
Authors: Steeb Holger , Diebels Stefan 
Published: December 2005

AbstractIn the present contribution we discuss an axiomatic stucture of extended continua with affine microstructure in the sense of Eringen [2]. Postulating and evaluating the observer‐invariance of the balance of energy we obtain the governing balance equations of generalized continua which are closed by a specific set of kinematical assumptions and constitutive equations. Furthermore, we discuss two specific models characterized by an additional scalar (volumetrical) order parameter. Interestingly, the resulting effects lead to completely different interpretations of the results with respect to the coupling effects. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantitative proteome analysis of CD95 (Fas/Apo‐1)‐induced apoptosis by stable isotope labeling with amino acids in cell culture, 2‐DE and MALDI‐MS
Authors: Thiede Bernd , Kretschmer Annikki , Rudel Thomas 
Published: December 2005

AbstractProteome analysis of Jurkat T cells induced to undergo apoptosis by CD95 (Fas/Apo‐1) treatment was performed to identify modified proteins. We used stable isotope labeling with amino acids in cell culture (SILAC) using leucine to identify proteins of apoptotic and control Jurkat T cells by 2‐DE and MALDI‐MS. Out of 224 spots analyzed, we quantified 213 spots with 3.5 leucine‐containing peptide pairs on average; 28 proteins with a relative abundance of higher than 1.5 were found. Five new modified proteins including calcyclin binding protein, cytosolic acyl coenzyme A thioester hydrolase, heterogeneous ribonucleoprotein M, replication factor C 37‐kDa subunit, and tropomyosin 4 chain were identified as being modified in response to apoptosis. In comparison to differential proteome analysis via silver‐stained 2‐D gels and PMF of total Jurkat T cell lysates, 15 additional apoptosis‐modified proteins were identified though 8 proteins were not found. The described approach using SILAC instead of silver staining for relative quantification was simpler to perform regarding the number of required 2‐D gels, that cumbersome gel comparisons were avoided, and more apoptosis‐modified proteins were identified, but with a higher demand on data interpretation of the mass spectra obtained.
Proteomic analysis of malignant lymphocyte membrane microparticles using double ionization coverage optimization
Authors: Miguet Laurent , Pacaud Karine , Felden Claire , Hugel Bénédicte , Martinez M. Carmen , Freyssinet Jean‐Marie , Herbrecht Raoul , Potier Noelle , van Dorsselaer Alain , Mauvieux Laurent 
Published: December 2005

AbstractShed membrane microparticles (MPs) are microvesicles generated from the plasma membrane when cells are submitted to stress conditions. Although MPs reflect the cell state (at least in vitro), little is known on their protein composition. We describe the first set of experiments aiming to characterize the MP proteome. Two ways of triggering MP formation from a T‐lymphocytic cell line were analyzed using a 1‐D gel approach coupled with LC‐MS/MS and the results were compared with those obtained from a classic membrane preparation. In total, 390 proteins were identified in MPs, among which 34% were localized to the plasma membrane. The MPs revealed a broad representation of plasma membrane proteins including 17 hematopoietic clusters of differentiation. This approach was successfully applied to one human chronic B‐cell lymphoid malignancy. In all, 413 proteins were identified, including 117 membrane proteins, many of them being pathology associated. The sequence coverage in identified proteins was improved combining both nano‐LC‐MS/MS and MALDI‐MS data. The suppression effect, observed on very complex peptide mixtures, was remediated by chromatographic fractionation. MPs may represent a new tool for studying plasma membrane proteins, displaying the advantages of reproducibility, minimal organelle contamination, and being potentially applicable to most cell types.
Pedigree analysis of an elite rice hybrid using proteomic approach
Authors: Xie Zhensheng , Wang Jingqiang , Cao Mengliang , Zhao Caifeng , Zhao Kang , Shao Jianmin , Lei Tingting , Xu Ningzhi , Liu Siqi 
Published: December 2005

AbstractThe definition of dominance or epistasis is generally on the basis of a descriptive characterization for these crops in the field, such as yield per hectare and the weight of grain. Since these trait examinations lack molecular information, how to precisely predict the phenotypic changes in filial generation is still a problem in heterosis studies. For rice, the genetic information caused by hybridization can be archived through analyzing of proteomes of rice seeds. Differential analysis of proteomes was introduced for the rice seeds of three cultivars, 9311, PA64S and LYP9, an elite rice hybrid from cross between 9311 and PA64S. In the three rice endosperms, the expression profiles of proteins were similar with the stained spots of 47 ± 1, 46 ± 0.6 and 44 ± 0.6, for 9311, PA64S and LYP9, respectively; however, the number of proteins expressed in the rice embryos was significantly increased with the stained spots of 395.3 ± 12.9, 350 ± 9.2, and 389.3 ± 16.4, for 9311, PA64S and LYP9, respectively. Importantly, the image comparisons and protein identifications have revealed in significantly different embryo protein spots among the three rice cultivars. By carefully analyzing these different 2‐DE spots, many of them from the three embryos were shown to display a mirrored relationships between parents and the first filial generation. Furthermore, all of stained spots in LYP9 embryo were found on the 2‐DEs from its parents, indicating that there was a genetic linkage. These results suggest that proteomic approach is able to serve pedigree analysis and functional prediction for new rice breeds.
Short‐range ±J interaction Ising spin glass in a transverse field on a Bethe lattice: a quantum‐spherical approach
Authors: Kopeć T. K. , Usadel K. D. 
Published: December 2005

AbstractWe consider the short‐range interaction disordered quantum Ising model with symmetric binary ±J bond distribution on the Bethe lattice (with coordination number z). The system exhibits quantum phase transition separating the spin glass and disordered phases where the quantum effect are regulated by a param‐ eter Δ describing the transverse field. By introducing a mapping of the quantum Hamiltonian of the model onto a soft‐spin action we consider it truncated version in a form of the solvable quantized spherical model. Quantum dynamics is examined via various correlation functions on the infinite tree which are evaluated in a closed form. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The study of structural transitions in liquid crystal droplets doped with magnetic particles
Authors: Kopčanský P. , Koneracká M. , Timko M. , Jadzyn J. 
Published: December 2005

AbstractThe magnetically active ferronematic droplets were prepared in solutions of nematic liquid crystal 6CHBT with fine magnetic particles, dissolved in phenyl isocyanate. The phase diagram of the transitions between isotropic, droplet and nematic phases in prepared sample was found. The structural transitions in 6CHBT‐based ferronematic and in 6CHBT ferronematic droplets, exposed to external fields, were investigated. The possibility to use the observations of structural transitions for the determination of the type of anchoring of nematic molecules on magnetic particles surfaces was demonstrated. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin transport and spin relaxation in semiconductor heterostructures with Rashba spin–orbit interaction
Authors: Bleibaum O. 
Published: December 2005

AbstractSpin diffusion equations, which also contain the coupling between spins and charges, are discussed for semiconductor heterostructures with Rashba spin–orbit interaction in the presence of an electric field. The diffusion equations are applied to an investigation of the decay of a homogeneous initial magnetization. A field induced precession, which is observable if the electric field exceeds a characteristic field, is obtained. Moreover, the impact of quantum corrections on the spin transport coefficients is discussed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enantiomeric separation and quantification of pindolol in human plasma by chiral liquid chromatography/tandem mass spectrometry using staggered injection with a CTC Trio Valve system
Authors: Wang Haiping , Shen Zhongzhou 
Published: December 2005

AbstractPindolol is a non‐selective β‐adrenergic antagonist (β‐blocker) for the treatment of cardiovascular diseases such as hypertension and angina pectoris. It has one chiral center, and, therefore, two optical isomers. It was essential to develop an enantioselective assay to measure each enantiomer in human plasma. However, separation of enantiomers using chiral chromatography usually requires relatively long retention times. This can pose a problem for rapid turnaround of a large number of samples (i.e., clinical studies). In the present study, a simple and sensitive chiral liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) method was developed and validated for the determination of S‐(−)‐ and R‐(+)‐pindolol in human plasma. To increase throughput, staggered sample injection was employed using a CTC Trio Valve system on a CTC HTS PAL autosampler. The method exhibited good intra‐ and inter‐day accuracy and precision, and was linear over a dynamic range of 250 pg/mL to 250 ng/mL for each pindolol enantiomer. Intra‐ and inter‐day accuracy ranged between 90.0–106% and 91.6–104% for both quality control (QC) samples of S‐(−)‐ and R‐(+)‐pindolol, respectively. The respective intra‐ and inter‐day precision ranged between 4.24–7.86% and 4.98–10.4%. Copyright © 2005 John Wiley & Sons, Ltd.
Fragmentation of mycosporine‐like amino acids by hydrogen/deuterium exchange and electrospray ionisation tandem mass spectrometry
Authors: Cardozo Karina H. M. , Carvalho Valdemir M. , Pinto Ernani , Colepicolo Pio 
Published: December 2005

AbstractThe determination and identification of mycosporine‐like amino acids (MAAs) from algae remain a major challenge due to the low concentration. Mass spectrometry (MS) can make an invaluable contribution in the search and identification of MAAs because of its high sensitivity, possibility of coupling with liquid chromatography, and the availability of powerful tandem mass spectrometric techniques. However, the unequivocal determination of the presence and location of important functional groups present on the basic skeleton of the MAAs is often elusive due to their inherent instability under MS conditions. In this study, the use of hydrogen/deuterium (H/D) exchange and electrospray ionisation tandem mass spectrometry (ESI‐MS/MS) for characterisation of four MAAs (palythine, asterina, palythinol and shinorine) isolated from the macroalgae Gracilaria tenuistipitata Chang et Xia was investigated. The accurate‐mass confirmation of the protonated molecules was performed on a Q‐TOF instrument. We demonstrate that employing deuterium labelling in ESI‐MS/MS analysis provides a convenient tool for the determination of new MAAs. Although the fragmentation patterns of MAAs were discussed earlier, to our knowledge, this is the first time that mechanisms are proposed. Copyright © 2005 John Wiley & Sons, Ltd.
Experimental apparatus for investigation of sputtering and secondary ion emission induced by energetic ion beams
Authors: Drozdziel A. , Pyszniak K. , Sielanko J. , Turek M. , Wójtowicz A. 
Published: December 2005

AbstractThe construction of an experimental apparatus, for investigation of implantation, secondary ion emission and sputtering processes, during irradiation of samples with an ion beam of up to 70 keV energy, is described. The basis of the apparatus is an electromagnetic mass separator equipped with a quadrupole mass spectrometer located in the collector chamber. The computer data acquisition control system makes it possible to perform the experimental measurements with high accuracy and precision. Preliminary results of secondary ion mass spectral measurements, obtained for C, Al, Si and Cu targets bombarded with Ar+ and Kr+ ions, are presented. Copyright © 2005 John Wiley & Sons, Ltd.
Molecular Signatures in the Transport Properties of Molecular Wire Junctions: What Makes a Junction “Molecular”?
Authors: Troisi Alessandro , Ratner Mark A. 
Published: December 2005

AbstractThe simplest component of molecular electronics consists of a single‐molecule transport junction: a molecule sandwiched between source and drain electrodes, with or without a third gate electrode. In this Concept article, we focus on how molecules control transport in metal‐electrode molecular junctions, and where the molecular signatures are to be found. In the situation where the molecule is relatively short and the gap between injection energy and molecular eigenstates is large, transport occurs largely by elastic tunneling, stochastic switching is common, and the vibronic signature can be found using inelastic electron tunneling spectroscopy (IETS). As the energy gaps for injection become smaller, one begins to see stronger molecular signatures – these include Franck–Condon‐like structures in the current/voltage characteristic and strong vibronic interactions, which can lead to hopping behavior at the polaron limit. Conformational changes induced by the strong electric field lead to another strong manifestation of the molecular nature of the junction. We overview some of this mechanistic landscape, focusing on significant effects of switching (both stochastic and controlled by the electric field) and of molecular vibronic coupling.
Homocystinuria: The effect of pyridoxine supplementation on cultured skin fibroblasts
Authors: Bittles A. H. , Carson N. A. J. 
Published: December 2005

AbstractSix skin fibroblast cultures, two derived from pyridoxine responsive homocystinurics, two from pyridoxine non‐responsive homocystinurics, one from an obligate heterozygote and one from a normal control were grown for three passages in the presence of 9.7 µmol/l, 243 µmol/l and 486 µmol/l of pyridoxine respectively. Cystathionine β‐synthase activity was stimulated in all four homocystinuric cell strains at 486 µmol/l; aspartate and alanine aminotransferase activity was also increased, particularly in the pyridoxine responsive cell strains. There was, however, evidence of cytotoxicity at the pyridoxine levels of 243 µmol/l and 486 µmol/l.
Acute hereditary tyrosinaemia type I: Clinical, biochemical and haematological studies in twins
Authors: Gray R. G. F. , Patrick A. D. , Preston F. E. , Whitfield M. F. 
Published: December 2005

AbstractAffected twins with acute hereditary tyrosinaemia type I are described. Attempts at therapy with a phenylalanine‐tyrosine‐methionine restricted diet supplemented with cysteine, vitamin E and ascorbic acid failed to influence the course of the disorder. The bleeding diathesis was due to a morbid reduction of a number of clotting factors, particularly factor VII, and this was associated with impaired platelet aggregation and release. The liver of one showed a marked reduction in fumarylacetoacetate lyase activity and her urine contained a potent inhibitor of red cell δ‐aminolaevulinic acid dehydratase. Biochemical investigations of cultured fibroblasts suggest that these do not express the disorder and are unlikely to prove useful diagnostically.
Hepatic phenylalanine hydroxylase activity in hyperphenylalaninaemia
Authors: Dhondt J. L. , Farriaux J. P. 
Published: December 2005

AbstractPhenylalanine tolerancein vivo has been compared with the phenylalanine hydroxylase activity of liver biopsy specimens in 14 newly detected cases of hyperphenylalaninaemia. Hepatic phenylalanine hydroxylase activity does not predict the degree of dietary restriction that will be required.
Hyperornithinaemia associated with gyrate atrophy of the choroid and retina:In vivo andIn vitro response to vitamin B6
Authors: Tada K. , Saito T. , Omura K. , Hayasaka S. , Mizuno K. 
Published: December 2005

AbstractThree Japanese cases of hyperornithinaemia due to a defect in ornithine ketoacid transaminase are described. Different types of disease in responsiveness to vitamin B6 were found.In vivo response to B6 correlated within vitro data.
Late onset type of propionic acidaemia: Case report and biochemical studies
Authors: Merinero B. , DelValle J. A. , Jiménez A. , Garcia M. J. , Ugarte M. , Solaguren R. , López O. , Condado I. 
Published: December 2005

AbstractA late‐onset case of propionic acidaemia with favourable response to restriction of dietary protein is described. During a keto‐acidotic crisis, this patient demonstrated unexpectedly low concentrations of propionic acid and glycine in blood and urine but increased urinary output of some secondary metabolites.
Neonatal I‐cell disease: Clinical and biochemical observations
Authors: Ohta H. , Mori T. , Eto Y. , Maekawa K. 
Published: December 2005

AbstractAcid hydrolases have been determined in serum, urine and brain of a neonatal case of I‐cell disease. Hexosamine and hexose contents of several tissues were elevated and the urinary excretion of bound sialic acid was very much increased.
Multiple sulphatase deficiency with early onset
Authors: Vamos E. , Liebaers I. , Bousard N. , Libert J. , Perlmutter N. 
Published: December 2005

AbstractThis male infant was first brought to attention in the neonatal period because he presented clinical and radiological evidence of multiple bone deformities. He was readmitted at 2 1/2 months for hydrocephaly, hepatosplenomegaly and poor somatic and psychomotor development. In addition, coarse facies, corneal opacities and stiff joints were noticed. Bone X‐ray anomalies and vacuolized lymphocytes supported the clinical presumption of lysosomal storage disorder. The diagnosis of multiple sulphatase deficiency rests on the presence of MPS and sulphatides in the urine, the finding of a mixed storage process in conjunctival biopsy and the demonstration of deficiencies in arylsulphatases A, B, C, iduronate sulphatase and heparan sulphatase in serum, leukocytes and cultured fibroblasts.