bluuebunny/crossref_metadata_2025 huggingface dataset:
Mutation analysis of PIK3CA and PIK3CB in esophageal cancer and Barrett's esophagus
Authors: Phillips Wayne A. , Russell Sarah E. , Ciavarella Marianne L. , Choong David Y.H. , Montgomery Karen G. , Smith Katherine , Pearson Richard B. , Thomas Robert J.S. , Campbell Ian G.
Published: December 2005

Mutation of PIK3CA, the gene coding for the p110α catalytic subunit of phosphoinositide 3‐kinase (PI3K), has been reported in a limited range of human tumors. We now report that PIK3CA is also mutated in esophageal tumors. Single‐strand conformational polymorphism (SSCP) and denaturing high‐performance liquid chromatography (DHPLC) were used to screen all 20 exons of PIK3CA in 101 samples from 95 individuals with esophageal cancer and/or Barrett's esophagus. Somatic mutation of PIK3CA was detected in 4 of 35 (11.8%) of esophageal squamous cell carcinomas (SCC) and 3 of 50 (6%) adenocarcinomas. No mutations were detected in any of 17 samples of Barrett's esophagus. For PIK3CB, we screened exons 11 and 22, which code for the regions corresponding to the exon 9 and 20 mutational ‘hotspots’ of PIK3CA. No somatic changes were detected in PIK3CB This study extends previous observations in other tumor types by demonstrating the presence of somatic PIK3CA mutations in both SCC and adenocarcinoma of the esophagus, thus implicating the PI3K pathway in the initiation and/or progression of esophageal cancers. © 2005 Wiley‐Liss, Inc.
Evaluation of RAD50 in familial breast cancer predisposition
Authors: Tommiska Johanna , Seal Sheila , Renwick Anthony , Barfoot Rita , Baskcomb Linda , Jayatilake Hiran , Bartkova Jirina , Tallila Jonna , Kaare Milja , Tamminen Anitta , Heikkilä Päivi , Evans D. Gareth , Eccles Diana ,   Breast Cancer Susceptibility Collaboration (UK), Aittomäki Kristiina , Blomqvist Carl , Bartek Jiri , Stratton Michael R. , Nevanlinna Heli , Rahman Nazneen
Published: December 2005

The genes predisposing to familial breast cancer are largely unknown, but 5 of the 6 known genes are involved in DNA damage repair. RAD50 is part of a highly conserved complex important in recognising, signalling and repairing DNA double‐strand breaks. Recently, a truncating mutation in the RAD50 gene, 687delT, was identified in 2 Finnish breast cancer families. To evaluate the contribution of RAD50 to familial breast cancer, we screened the whole coding region for mutations in 435 UK and 46 Finnish familial breast cancer cases. We identified one truncating mutation, Q350X, in one UK family. We screened a further 544 Finnish familial breast cancer cases and 560 controls for the 687delT mutation, which was present in 3 cases (0.5%) and 1 control (0.2%). Neither Q350X nor 687delT segregated with cancer in the families in which they were identified. Functional analyses suggested that RAD50 687delT is a null allele as there was no detectable expression of the mutant protein. However, the wild‐type allele was retained and expressed in breast tumors from mutation carriers. The abundance of the full‐length RAD50 protein was reduced in carrier lymphoblastoid cells, suggesting a possible haploinsufficiency mechanism. These data indicate that RAD50 mutations are rare in familial breast cancer and either carry no, or a very small, increased risk of cancer. Altogether, these results suggest RAD50 can only be making a very minor contribution to familial breast cancer predisposition in UK and Finland. © 2005 Wiley‐Liss, Inc.
Classification of designs with nontrivial automorphism groups
Authors: Eslami Ziba
Published: December 2005

In this article, we introduce a new orderly backtrack algorithm with efficient isomorph rejection for classification of t‐designs. As an application, we classify all simple 2‐(13,3,2) designs with nontrivial automorphism groups. The total number of such designs amounts to 1,897,386. The decomposability of the designs is also considered. © 2005 Wiley Periodicals, Inc. J Combin Designs 14: 479–489, 2006
Possible selves and borderline personality disorder
Authors: Janis Irene Belle , Veague Heather Barnett , Driver‐Linn Erin
Published: December 2005

Although clinical theories suggest that people with Borderline Personality Disorder (BPD) experience a confused sense of self, little empirical research has directly examined the self in BPD (Heard & Linehan, 1993; Westen & Cohen, 1993). In this study, 43 female participants, 15 with BPD and 28 without BPD, completed the closed‐ended version of Markus and Wurf's (1987) Possible Selves Questionnaire (PSQ). Participants with BPD were less likely than controls to endorse positive possible selves as current, but more likely to endorse negative possible selves as current, probable, desired, and important. Participants with BPD linked negative and positive selves to their desired selves, which is consistent with the unstable sense of self characteristic of BPD. © 2005 Wiley Periodicals, Inc. J Clin Psychol 62: 387–394, 2006.
Tobacco intervention practices of licensed psychologists
Authors: Leffingwell Thad R. , Babitzke Alison C.
Published: December 2005

Tobacco dependence is a serious public health concern. The U.S. Department of Health and Human Services has issued a practice guideline of best practices to encourage all health care providers to intervene with tobacco‐dependent individuals they encounter. Psychologists may be ideally suited to implement brief tobacco interventions due to their expertise in behavior change strategies and interpersonal counseling skills. This study sought to investigate current tobacco assessment and intervention practices and perceptions of responsibility for tobacco intervention among a regional sample of licensed, practicing psychologists. Results suggest that a majority of psychologists fall far short of the ideal best practices recommended in the practice guideline, and many are unaware of the availability of the guidelines. Further, psychologists in this study perceived tobacco intervention to be a greater responsibility of physicians and other health care providers than of psychologists and other mental health professionals. © 2005 Wiley Periodicals, Inc. J Clin Psychol 62: 313–323, 2006.
Mechanisms of mindfulness
Authors: Shapiro Shauna L. , Carlson Linda E. , Astin John A. , Freedman Benedict
Published: December 2005

Recently, the psychological construct mindfulness has received a great deal of attention. The majority of research has focused on clinical studies to evaluate the efficacy of mindfulness‐based interventions. This line of research has led to promising data suggesting mindfulness‐based interventions are effective for treatment of both psychological and physical symptoms. However, an equally important direction for future research is to investigate questions concerning mechanisms of action underlying mindfulness‐based interventions. This theoretical paper proposes a model of mindfulness, in an effort to elucidate potential mechanisms to explain how mindfulness affects positive change. Potential implications and future directions for the empirical study of mechanisms involved in mindfulness are addressed. © 2005 Wiley Periodicals, Inc. J Clin Psychol 62: 373–386, 2006.
Non‐linearity influences on the axial secular‐motion spectrum of ions confined in a Fourier transform ion trap mass spectrometer. Experimental studies
Authors: Carette M. , Zerega Y.
Published: December 2005

A Fourier transform operating mode is applied to an ion trap. The trap is truncated at 2r0 and presents unwanted defects that induce confinement electric‐field non‐linearities.

Ion axial secular‐motion spectrum is examined by experiments near the resonance line βz = 0.5. Ion‐loss processes and ion axial‐motion peak splitting are observed.

In the non‐linear ion trap, the ion‐motion frequency depends on its initial conditions in position and velocity. This brings an enlargement of the motion‐frequency peak and limits the resolution.

With a 2r0 truncated ion trap, the Fourier transform ion trap mass spectrometer (FTIT‐MS) leads experimentally to a mass resolution of about 4000 at 130 u. Copyright © 2005 John Wiley & Sons, Ltd.
Effective detection of peptides containing cysteine sulfonic acid using matrix‐assisted laser desorption/ionization and laser desorption/ionization on porous silicon mass spectrometry
Authors: Kinumi Tomoya , Shimomae Yukiyasu , Arakawa Ryuichi , Tatsu Yoshiro , Shigeri Yasushi , Yumoto Noboru , Niki Etsuo
Published: December 2005

Cysteine sulfonic acid‐containing peptides, being typical acidic peptides, exhibit low response in matrix‐assisted laser desorption/ionization (MALDI) mass spectrometry. In this study, matrix conditions and the effect of diammonium hydrogencitrate (DAHC) as additive were investigated for ionization of cysteine sulfonic acid‐containing peptides in MALDI. A matrix‐free ionization method, desorption/ionization on porous silicon (DIOS), was also utilized to evaluate the effect of DAHC. When equimolar three‐component mixtures of peptides carrying free cysteine, cysteine sulfonic acid, and carbamidomethyl cysteine were measured by MALDI using a common matrix, α‐cyano‐4‐hydroxycinnamic acid (CHCA), no signal corresponding to cysteine sulfonic acid‐containing peptide could be observed in the mass spectrum. However, by addition of DAHC to CHCA, the peaks of cysteine sulfonic acid‐containing peptides were successfully observed, as well as when using 2,4,6‐trihydroxyacetophenone (THAP) and 2,6‐dihydroxyacetophenone with DAHC. In the DIOS mass spectra of these analytes, the use of DAHC also enhanced the peak intensity of the cysteine sulfonic acid‐containing peptides. On the basis of studies with these model peptides, tryptic digests of oxidized peroxiredoxin 6 were examined as a complex peptide mixture by MALDI and DIOS. In MALDI, the peaks of cysteine sulfonic acid‐containing peptides were observed when using THAP/DAHC as the matrix, but this was not so with CHCA. In DIOS, the signal from cysteine sulfonic acid‐containing peptides was suppressed; however, the use of DAHC significantly enhanced the signal intensity with an increase in the number of observed peptides and increased signal‐to‐noise ratio in the DIOS spectra. The results show that DAHC in the matrix or on the DIOS chip decreases discrimination and suppression effects in addition to suppressing alkali‐adduct ions, which leads to a beneficial effect on protonation of peptides containing cysteine sulfonic acid. Copyright © 2005 John Wiley & Sons, Ltd.
Differential expression of the four untranslated BDNF exons in the adult mouse brain
Authors: Malkovska Irena , Kernie Steven G. , Parada Luis F.
Published: December 2005

Brain‐derived neurotrophic factor (BDNF) is a member of the neurotrophin family of secreted proteins and has important functions in the peripheral and central nervous systems (CNS). Its gene organization is complex, comprising four untranslated exons, each with an associated promoter. We have examined the expression of the four untranslated exons in direct comparison to one another and to the fifth BDNF coding exon by in situ hybridization. Other studies have examined untranslated exon expression in several brain regions in response to specific stimuli; however, this is the first detailed study to describe endogenous exon 1–4 expression throughout the adult mouse brain at baseline conditions. The differential expression of the four untranslated exons seen throughout the brain indicates a complex regulation of BDNF. © 2005 Wiley‐Liss, Inc.
Reorganization of CA3 area of the mouse hippocampus after pilocarpine induced temporal lobe epilepsy with special reference to the CA3‐septum pathway
Authors: Ma Dong Liang , Tang Yong Cheng , Chen Peng Min , Chia Shwn Chin , Jiang Feng Li , Burgunder Jean‐Marc , Lee Wei Ling , Tang Feng Ru
Published: December 2005

We showed that when CA3 pyramidal neurons in the caudal 80% of the dorsal hippocampus had almost disappeared completely, the efferent pathway of CA3 was rarely detectable. We used the mouse pilocarpine model of temporal lobe epilepsy (TLE), and injected iontophoretically the anterograde tracer phaseolus vulgaris leucoagglutinin (PHA‐L) into gliotic CA3, medial septum and the nucleus of diagonal band of Broca, median raphe, and lateral supramammillary nuclei, or the retrograde tracer cholera toxin B subunit (CTB) into gliotic CA3 area of hippocampus. In the afferent pathway, the number of neurons projecting to CA3 from medial septum and the nucleus of diagonal band of Broca, median raphe, and lateral supramammillary nuclei increased significantly. In the hippocampus, where CA3 pyramidal neurons were partially lost, calbindin, calretinin, parvalbumin immunopositive back‐projection neurons from CA1–CA3 area were observed. Sprouting of Schaffer collaterals with increased number of large boutons in both sides of CA1 area, particularly in the stratum pyramidale, was found. When CA3 pyramidal neurons in caudal 80% of the dorsal hippocampus have almost disappeared completely, surviving CA3 neurons in the rostral 20% of the dorsal hippocampus may play an important role in transmitting hyperactivity of granule cells to surviving CA1 neurons or to dorsal part of the lateral septum. We concluded that reorganization of CA3 area with its downstream or upstream nuclei may be involved in the occurrence of epilepsy. © 2005 Wiley‐Liss, Inc.
Abstract wave equations with acoustic boundary conditions
Authors: Mugnolo Delio
Published: December 2005

We define an abstract setting to treat wave equations equipped with time‐dependent acoustic boundary conditions on bounded domains of Rn . We prove a well‐posedness result and develop a spectral theory which also allows to prove a conjecture proposed in [13]. Concrete problems are also discussed. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Construction of systems of differential equations of Okubo normal form with rigid monodromy
Authors: Yokoyama Toshiaki
Published: December 2005

For systems of differential equations of the form (xI n – T )dy /dx = Ay (systems of Okubo normal form), where A is an n × n constant matrix and T is an n × n constant diagonal matrix, two kinds of operations (extension and restriction) are defined. It is shown that every irreducible system of Okubo normal form of semi‐simple type whose monodromy representation is rigid is obtained from a rank 1 system of Okubo normal form by a finite iteration of the operations. Moreover, an algorithm to calculate the generators of monodromy groups for rigid systems of Okubo normal form is given. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Formation and Detection of Clay Network Structure in Poly(propylene)/Layered Silicate Nanocomposites
Authors: Ábrányi Ágnes , Százdi László , Pukánszky Béla , Vancsó G. Julius , Pukánszky Béla
Published: December 2005

Summary: The study of the structure and the rheological properties of poly(propylene) (PP)/montmorillonite (MMT)/maleinated PP (MAPP) composites strongly suggests that a silicate network may form under certain conditions. Network formation could not be proven unambiguously with the usual techniques, i.e., with TEM and by plotting the frequency dependence of viscoelastic properties. Cole‐Cole plots detect the network very sensitively. A certain number of silicate layers are needed to create a house‐of‐cards structure. A threshold concentration of MAPP exists in the investigated system, which depends on the silicate content.

Cole‐Cole representation of the viscoelastic properties of PP/OMMT/MAPP nanocomposites.

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Cole‐Cole representation of the viscoelastic properties of PP/OMMT/MAPP nanocomposites.
Electrospinning of Hyaluronic Acid (HA) and HA/Gelatin Blends
Authors: Li Junxing , He Aihua , Han Charles C. , Fang Dufei , Hsiao Benjamin S. , Chu Benjamin
Published: December 2005

Summary: In the present study, electrospinning of hyaluronic acid (HA) and hyaluronic acid/gelatin (HA‐GE) blends in N,N‐dimethylformamide (DMF)/water‐mixed solvents have been investigated. When the volume ratio of DMF to water was in the range of 1.5–0.5, HA solutions could be electrospun into fibrous membranes successfully. The average diameter of HA fibers was about 200 nm. The HA‐GE composite nanofibrous membranes with varied HA/GE weight ratio in the range of 100/20–100/100 have also been successfully fabricated. The average diameter of HA‐GE fibers was in the range of 190–500 nm. The decrease in surface tension could promote fiber formation. Thus, an introduction of DMF that could decrease the surface tension distinctively, without significant change or increase in viscosity of the solution, could bypass the use of blowing‐assisted electrospinning. Our postulated picture is that the lower surface tension could help the ejection of stream with relatively high viscosity and reduce or prevent the droplet formation during the spinning process.

HA/GE (100/80) nanofibrous membrane produced by electrospinning.

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HA/GE (100/80) nanofibrous membrane produced by electrospinning.
SCF Theory of a Polymer Brush Immersed into a Multi‐Component Solvent
Authors: Amoskov Victor M. , Birshtein Tatiana M. , Mercurieva Anna A.
Published: December 2005

Summary: Self‐consistent field (SCF) theory is developed for a polymer brush immersed into a multi‐component solvent. Thermodynamics of the plane inhomogeneous brush is mainly determined by thermodynamics of the basic system, i.e., a homogeneous solution of a polymer dissolved in a multi‐component solvent that is in partial (or membrane) equilibrium with a bulk. Binary solvent with partially miscible components is in the focus of this investigation. The peculiarities of the brush are studied on the basis of the phase diagrams constructed for the basic system. Non‐trivial effects are demonstrated: microphase segregation of the brush and collapse of the brush under its filling with a good solvent in a pre‐binodal region of the bulk mixed solvent. Mathematical apparatus is developed and allows obtaining phase diagrams, density profiles, and other characteristics of the system under consideration.

Polymer brush immersed into mixed solvent.

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Polymer brush immersed into mixed solvent.
Prediction of Glass Transition Temperatures for Polystyrenes by a Four‐Descriptors QSPR Model
Authors: Yu Xinliang , Wang Xueye , Li Xiaobing , Gao Jinwei , Wang Hanlu
Published: December 2005

Summary: A set of new molecular descriptors, RSC, SMC, DHB and MPE, which are obtained directly from polystyrenes monomer structures, are used to predict the Tg values of polystyrenes and generate a QSPR model by multiple linear stepwise regression analysis, with R = 0.959 and s = 15.20 K. Compared with the existing QSPR models, the proposed model requires only four descriptors, which can be obtained by simple calculation and makes it more valuable to predict the Tg values of polymers.

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Hsp90 inhibitors: Small molecules that transform the Hsp90 protein folding machinery into a catalyst for protein degradation
Authors: Blagg Brian S. J. , Kerr Timothy D.
Published: December 2005

The 90 kDa heat shock proteins (Hsp90) are responsible for the conformational maturation of nascent polypeptides and the renaturation of denatured proteins. In transformed cells, numerous mutated and overexpressed proteins rely on the Hsp90 protein folding machinery for tumor progression. The Hsp90‐mediated protein folding process is dependent upon ATP, and when inhibitors of ATP are present, the Hsp90 machinery is unable to fold client proteins into their biologically active form, which results in the degradation of protein substrates via the ubiquitin‐proteasome pathway. Consequently, Hsp90 has evolved into a promising anti‐cancer target because multiple oncogenic proteins can be simultaneously degraded as a consequence of Hsp90 inhibition. This review serves to explain the Hsp90 protein folding process, the impact of Hsp90 inhibition, the identification of natural product inhibitors, and the development of rationally designed inhibitors of the Hsp90 protein folding machinery. © 2005 Wiley Periodicals, Inc.
Wideband internal folded planar monopole antenna for UMTS/WiMAX folder‐type mobile phone
Authors: Wong Kin‐Lu , Su Wei‐Cheng , Chang Fa‐Shian
Published: December 2005

A simple folded planar metal‐plate monopole antenna suitable for operation as a wideband internal antenna for a folder‐type mobile phone is presented. The folder‐type mobile phone is modeled to comprise an upper ground plane and a lower ground plane, and the proposed antenna is employed at the hinge position between the upper and lower ground planes. The antenna has a compact structure and yet generates a wide operating bandwidth of about 4.8 GHz (from about 1.7 to 6.5 GHz), allowing it to easily cover UMTS and WiMAX operations. Details of the proposed antenna are described, and the experimental results of constructed prototypes are presented and discussed. The effects of the various lengths of the upper ground plane on the impedance matching of the antenna are also studied. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 324–327, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21339
Clock synchronization using a linear process model
Authors: Aweya James , Montuno Delfin Y. , Ouellette Michel , Felske Kent
Published: December 2005

In this paper, we present a clock synchronization scheme based on a simple linear process model which describes the behaviors of clocks at a transmitter and a receiver. In the clock synchronization scheme, a transmitter sends explicit time indications or timestamps to a receiver, which uses them to synchronize its local clock to that of the transmitter. Here, it is assumed that there is no common network clock available to the transmitter and the receiver and, instead, the receiver relies on locking its clock to the arrival of the timestamps sent by the transmitter. The clock synchronization algorithm used by the receiver is based on a weighted least‐squares criterion. Using this algorithm, the receiver observes and processes several consecutive clock samples (timestamps) to generate accurate timing signals. This algorithm is very efficient computationally, and requires the storage of only a small number of clock samples in order to generate accurate timing signals. Copyright © 2006 John Wiley & Sons, Ltd.
MAN@RCHISES: new added‐services architecture in automatic management networking
Authors: Nguyen Tuan Loc , Ouakil Laurent , Pujolle Guy , Jamalipour Abbas
Published: December 2005

The environment of the telecommunications service operators is particularly complex today with the integration of very diverse services coming from the Internet. This complexity arises from an integration between telecommunications and the Internet. The generalization of the Internet continues to grow unabated, especially with the rapid adoption of mobile and fixed wireless connecting a myriad of devices in homes and businesses. It allows us to have more and more services at low cost. In the future, anyone with any kind of device at any times will have options to access any service from anywhere. In fulfilling this requirement, more rapid and profitable methods of service creation and management must be examined. In this context, MAN@RCHISES, a network‐based application concept, is proposed in this paper. This concept results in the integration of the Internet service concept and the intelligence in networking concept of the telecommunications world. MAN@RCHISES is an architecture in which the applications and the services are not ported onto a pre‐existing network, but where the network itself grows out of the applications and the services that end user demands. The major objective of this article is to propose a new architecture for the adaptive and self‐organizing ambient aware applications. Copyright © 2006 John Wiley & Sons, Ltd.
On averaging of the non‐periodic conductivity coefficient using two‐scale extensions
Authors: Laptev Vsevolod , Belouettar Salim
Published: December 2005

We consider a second order elliptic equation with known rapidly oscillated coefficient. The equation appears to describe such problems as heat transfer in composite materials, flow in non‐homogeneous porous media as well as in many others. For the periodic coefficient the averaging procedure is well known. The non‐periodic case is still a challenging problem. We present a two‐scale extension approach and apply it on one numerical example in 2D. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelling and Optimization of Cogeneration Plants
Authors: Lasch Peter , Büskens Christof , Knauer Matthias
Published: December 2005

Cogeneration plants have a long tradition in Germany and are used to transfrom a given energy into various destination energies, e.g. natural gas into mechanical, electrical and heat energy. In this paper a cogeneration plant composed of several components like gas turbines, waste heat boilers, steam turbines, etc, is modelled in steady state. The thermo‐dynamic behaviour of the plant is determined by a set of measured data, which is used to adopt the mathematical model to the real plant. By defining a suitable objective function incorporating e.g. emission trading, an appropriate NLP‐solver can be used to solve the generated model which includes several nonlinear constraints. Solutions for different environmental and business conditions are presented, to demonstrate the enormous potential of the proposed method for energy suppliers. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Methods of Resolution for the Poisson Equation on the 3D Ball
Authors: Michel Dominik
Published: December 2005

Within the article at hand, we investigate the Poisson equation solved by an integral operator, originating from an ansatz by Greens functions. This connection between mass distributions and the gravitational force is essential to investigate, especially inside the Earth, where structures and phenomena are not sufficiently known and plumbable. Since the operator stated above does not solve the equation for all square‐integrable functions, the solution space will be decomposed by a multiscale analysis in terms of scaling functions. Classical Euclidean wavelet theory appears not to be the appropriate choice. Ansatz functions are chosen to be reflecting the rotational invariance of the ball. In these terms, the operator itself is finally decomposed and replaced by versions more manageable, revealing structural information about itself. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the influence of aggressive driving behavior on the dynamics of traffic flow
Authors: Seidel Tilman , Gasser Ingenuin , Sirito Gabriele , Werner Bodo
Published: December 2005

The car following model under discussion is a system of ordinary differential equations describing N cars moving around a circular road. We extend the stability analysis of the model in two directions: variable reaction time (depending on the headway) and an additional part describing the aggressive driving tendency. We study the global bifurcation dynamics and in particular its dependence on these two new ingredients. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Method for allowing Local Editing of Globally Optimized Splines
Authors: Tändl Martin , Kecskeméthy Andrés
Published: December 2005

The present work describes an algorithm for modifying spline curves in the neighborhood of an editing point while preserving global smoothness properties. Current spline algorithms have either a graphical editing mode in which the user edits local properties of the spline, or a globally optimizing mode, in which the spline coefficients are determined such that overall properties e. g. smoothness, distance to support points, or physical behavior are optimized. With globally optimized splines, editing parameters at one point causes their transmission through the whole spline. Hence, the user has the impression that it is not possible to change the shape of the spline without disturbing the overall behavior. This can be circumvented by forcing the trajectory of the globally optimized curve to lie in the close vicinity of the original curve far away from the edited point. The present work describes an algorithm for local editing of spline curves that are produced by a global optimizer. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Web‐Accessible Tools for Interval Linear Systems
Authors: Popova Evgenija S.
Published: December 2005

Interval webComputing is a collection of dynamic interactive pages designed to make specialized interval computations and visualization widely accessible through web browsers. Discussed are the general conception and two typical components: visualization of solution sets to interval linear systems and solvers of parametric interval linear systems. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Comparison of Some Existence Tests
Authors: Schäfer Uwe , Schnurr Marco
Published: December 2005

We compare some tests to each other which guarantee the zero of a mapping from Rn to Rn . (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Qualified Thresholds forWavelet Shrinkage
Authors: Boese F. G.
Published: December 2005

One of many method for noise reduction in measured data is the wavelet‐based Wavelet Shrinkage propagated by D. L. Donoho, I. M. Johnstone et al. since about 1990. A crucial step within this approach is the setting of the treshold which decides whether a wavelet coefficient is considered as noise or as data. We propose an one‐paramerter family of thresholds. The parameter is the probability of making a false decision. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prediction of Extreme Ship Motions in Irregular Waves
Authors: Kreuzer Edwin , Sichermann Wolfgang
Published: December 2005

The occurrence of indirectly excited large amplitude roll motions of ships is investigated under the influence of a time‐varying righting lever curve in waves. In order to account for the irregular character of ocean waves appropriately, the ship motions are described within the framework of nonlinear dynamics and stochastic process theory. The analysis of roll motions in regular waves provides a qualitative understanding of the occurrence of unpredictable large amplitude roll motions as observed in ocean waves. However, quantitative information on the rolling behavior in irregular waves may be retrieved only from a probabilistic analysis. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vibration of a Beam on Random and Microperiodic Subsoil Caused by Moving Load
Authors: Mazur‐Sniady K. , Rystwej A. , Sniady P.
Published: December 2005

The subject of the analysis is a vibration problem of an infinitive beam resting on a foundation with periodic and stochastic parameters under a stochastic moving load. The problem is solved using the Tolerance Averaging Approximation procedure and also concept of a stochastic dynamic influence function. In this way we obtained an effective solution which may be applied in the railway engineering. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Estimation of the Bar Structure Safety with Respect to the Plastic Reserve of Material and Random Physical and Geometrical Parameters
Authors: Sieniawska Roza , Wysocka Alina , Zukowski Stanislaw
Published: December 2005

An approach for estimation of the bar structure safety is presented. It is assumed that the structure is made of an elasticperfectly plastic material, with random lengths of the elements, random dimensions of the cross‐sections and material parameters, is subjected to the dead and variable live loads and works in uniaxial state of stresses. It is also assumed that the probabilistic characteristics of the random parameters are known and that all random variables are mutually independent. As the structure safety measure the reliability index is regarded. A new formula for reliability index estimation is proposed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sensitivity analysis of uncertain structures subject to stochastic load in the framework of SFEM
Authors: Zielichowski‐Haber W.
Published: December 2005

In the paper, sensitivity analysis of linear system with uncertain parameters subject to stochastic stationary and non stationary stochastic point process is presented. The proposed approach for the design sensitivity of probabilistic system is formulated in the framework of Stochastic FEM on the basis of the concept of a sensitivity random influence vector in the context of correlation theory i.e. restricted to the probabilistic moments of second order. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An Extension of the Conjugate Directions Method With Orthogonalization to Large‐Scale Problems With Bound Constraints
Authors: Boudinov Edouard , Manevich Arkadiy
Published: December 2005

In our previous works a new method of conjugate directions for large‐scale unconstrained minimization problems has been presented [1, 2]. In the paper this algorithm is extended to minimization problems with bound constraints. Because the linear minimization along the newly found conjugate vector is not needed for constructing the next conjugate vector and one arbitrarily step‐size (not necessarily the optimal one) is calculated along this conjugate direction, we are able to incorporate naturally the bound constraints into the algorithm. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Parameter estimation for forward Kolmogorov equation with application to nonlinear exchange rate dynamics
Authors: Jäger Simon , Kostina Ekaterina
Published: December 2005

Diffusion processes are widely used for mathematical modeling in finance e.g. in modeling foreign exchange rates. Stochastic differential equations describing diffusion processes are linked directly to the forward Kolmogorov equations. In order to calibrate the models, efficient algorithms identifying the system parameters are in demand. Taking into account nonlinear effects in volatility and drift and dependence on observed economical data, which are not directly modeled, one obtains problems which cannot be treated by standard numerical methods. The coefficients are rapidly oscillatory and strong instabilities may arise. To handle these problem we develop special numerical methods, which are used to simulate the nonlinear dynamics of exchange rates depending on economic data. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multicriterion optimization of hybrid composite plates with various supports under transverse load
Authors: Kasprzak Jakub , Ostwald Marian
Published: December 2005

In this paper applications of multicriteria optimization to design hybrid laminates is shown. In the considered numerical example, the obtained preferred solution is 30% heavier than Carbon/Epoxy laminate and use a third of the more expensive material. Moreover, a small number of layers is needed to build an optimal solution. In the case of scalar optimization three layers are required. In the case of bicriteria optimization one E‐Glass/Epoxy layer placed between four Carbon/Epoxy layers is enough to build an optimal laminate. Two criteria may lead to a set of preferred equal solutions. Thus, connection of Pareto concept with a lexicographic order by introduction of an additional criterion is useful for ordering them. A similar approach may be used for designing hybrid laminates with a requirement of a compromise between the stiffness and cost of a plate. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bicriterion optimization of cold‐formed thin‐walled beams with I‐type shape
Authors: Rodak Marcin , Ostwald Marian
Published: December 2005

The work is devoted to bi‐criterion optimization of thin‐walled cold‐formed beams under pure bending. The first objective function is the area of a beam cross‐section and the maximum deflection of a beam is taken as the second one. The strength and stability constraints in bi‐objective optimization problem are taken into account and formulated analytically. Some results of numerical calculations are presented in the form of the tables. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Solving nonlinear eigenproblems by AMLS
Authors: Elssel Kolja , Voss Heinrich
Published: December 2005

In this paper we discuss the opportunity to construct suitable ansatz spaces by the automated multi–level substructuring method for nonlinear eigenvalue problems. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Boundary Integral Equation Method for the Numerical Modeling of Particles of Arbitrary Shape
Authors: Illyashenko‐Raguin Lyudmyla , Arbenz Peter
Published: December 2005

A variant of the Boundary Integral Equation method for the numerical study of dielectric particles has been developed. In addition to the advantages of the classical BEI method, the proposed modification allows to study the particles of almost arbitrary shape, including the accurate numerical treatment of the integral equation singularities and geometrical singularities of the particle boundary. It guarantees the fast and accurate solution with small computer resources. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multiscale Flow Simulation by Adaptive Finite Volume Particle Methods
Authors: Jürgens Markus
Published: December 2005

We present a discretisation of parabolic problems in the time direction based on piecewise linear wavelets. This discretisation of the solution admits a sparse representation, i.e. few coef.cients have to be stored to achieve a reasonable close approximation to the exact solution. To demonstrate the advantages of this method we provide numerical experiments for Tikhonov regularisation of the inverse heat equation. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Wavelets on the 3–dimensional Ball
Authors: Michel V.
Published: December 2005

In this article wavelets on a ball in ℝ3are introduced. Corresponding properties like an approximate identity and decomposition/reconstruction (scale step property) are proved. The advantage of this approach compared to a classical Fourier analysis in orthogonal polynomials is a better localization of the used ansatz functions. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Based on Walsh packet parametric identification technique for dynamic systems
Authors: Napiorkowska‐Alykow Magdalena , Glabisz Wojciech
Published: December 2005

The article presents an application of wavelet packet analysis in the parametric identification of discrete dynamic systems. The Walsh packet basis and their operational matrixes enables reduction of row derivatives, which are necessary in the procedure of identification of signal derivatives for systems, which are analyzed, and also enable algebraization their mathematical describe, what in combination with wavelet packet analysis with Haar filter properties decided on a great efficiency of parametric identification of linear systems procedure, which is built on wavelet packet analysis. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Method of order 1 + $\sqrt 2$ for the solution of nonlinear equations with Hölder continuous divided differences
Authors: Shakhno S. M.
Published: December 2005

We study an iterative method with order 1 + $\sqrt 2$ for solving nonlinear operator equations in Banach spaces. We present the received new results of local convergence, when the first‐order divided differences of a nonlinear operator are Hölder continuous. Method needs almost the same number of computations as the classical Secant method, but has a higher order of convergence. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The relationship between the models of perturbed Newton iterations, with applications
Authors: Cătinaş Emil
Published: December 2005

The quasi‐Newton method and the inexact Newton method are classical models of Newton iterates which take into account certain error terms. We have recently introduced the inexact perturbed Newton method, which takes into account all the possible sources of perturbations. We show that these models are in fact equivalent, in the sense that each one may be used to characterize the high convergence orders of the other two. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A New Eigenvalue Localization Theorem via Graph Theory
Authors: Cvetković Ljiljana , Kostić Vladimir
Published: December 2005

We give a generalization of a well‐known result of Brualdi concerning eigenvalue localization and compare this generalization with related results in this area. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Die beschleunigte Ritz‐Iteration im Eigenwertalgorithmus ECP
Authors: Falk S. , Wagner N.
Published: December 2005

Die Eigenwerte einer Polynommatrix werden parallel und in beliebiger Reihenfolge aus einer skalaren Gleichung iterativ berechnet und eingeschlossen. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Using Core Formulations for Ill‐posed Linear Systems
Authors: Sima Diana M. , Van Huffel Sabine
Published: December 2005

We investigate the application of core problem formulations to the context of ill‐posed linear algebraic systems. We note that in order to impose regularization on such systems by using core formulations, one is lead to a technique similar to the Truncated (Total) Least Squares method. Choosing an appropriate truncation level from given data can be made efficient by incorporating the truncation level decision as a stopping criterion into a partial bidiagonalization algorithm. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Relaxed Krylov subspace approximation
Authors: Simoncini Valeria , Szyld Daniel B.
Published: December 2005

Recent computational and theoretical studies have shown that the matrix‐vector product occurring at each step of a Krylov subspace method can be relaxed as the iterations proceed, i.e., it can be computed in a less exact manner, without degradation of the overall performance. In the present paper a general operator treatment of this phenomenon is provided and a new result further explaining its behavior is presented. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Coupled Partial Differential Equations in Fuel Cell Models
Authors: Heidebrecht Peter , Sundmacher Kai
Published: December 2005

Mathematical models play a vital role in fuel cell development. Some of the aspects treated with the help of models are the analysis of steady state and transient system behaviour during regular operation or start‐up and shut‐down, optimisation of system design and operating conditions and failure detection by online observation. In this contribution, we present some typical equations for high temperature fuel cell models and demonstrate their numerical treatment. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The perturbation index of linear PDAEs with a hyperbolic part
Authors: Rang Joachim , Angermann Lutz
Published: December 2005

For numerous problems in science and engineering a refined modelling approach leads to initial‐boundary value problems for partial differential‐algebraic equations (PDAEs). A perturbation index of the variational formulation of the PDAE is introduced. As examples, the compressible Navier–Stokes equations and a model problem from MHD are considered. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multirate methods for the transient analysis of electrical circuits
Authors: Verhoeven A. , El Guennouni A. , ter Maten E. J. W. , Mattheij R. M. M.
Published: December 2005

Multirate integration is an important tool to increase the speed of the transient analysis of circuits. This paper shows an approach for the “Compound‐Fast” multirate algorithm how to control the errors at the coarse and the refined time‐grid by means of the independent stepsizes of these grids. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On Discrete Korn's Inequality for some Nonconforming Finite Element Approaches to Linear Elasticity
Authors: Attia Frank S. , Starke Gerhard
Published: December 2005

The role of the discrete Korn's inequality for some nonconforming .nite element approaches to linear elasticity is discussed. Such methods enable uniform approximation in the incompressible limit and may be used in combination with a standard displacement‐based variational principle or with a least‐squares mixed formulation. A proof of the discrete Korn's inequality for a .nite element space recently proposed by Mardal, Tai and Winther is sketched. Numerical results illustrate the performance of these MTW elements for nearly incompressible linear elasticity. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stabilized finite element schemes for generalized Oseen systems
Authors: Bause Markus
Published: December 2005

In recent works [1, 2], advanced approximation schemes for the numerical calculation of compressible viscous flow were developed, analyzed theoretically and applied successfully to benchmark problems. These methods are based on splitting the Poisson–Stokes system (1.1) describing the motion of a viscous compressible fluid into a generalized Oseen problem for the velocity and a hyperbolic transport equation for the density. Highly refined finite element techniques were proposed for the numerical solution of these separated subproblems of simpler structure; cf. [2]. In this paper, error estimates for a SUPG/(PSPG) and grad‐div stabilized finite element approximation of the generalized Oseen problems that arise in the course of the splitting procedure are presented. LBB‐stable pairs of finite element spaces are used for velocity and pressure. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Equilibrium shapes of a ferrofluid drop
Authors: Lavrova O. , Polevikov V. , Tobiska L.
Published: December 2005

A numerical solution strategy for calculating equilibrium free surfaces of a ferrofluid drop under the action of uniform magnetic fields is proposed. Based on this strategy, drop shapes of nonlinear magnetisable fluids are obtained numerically in a wide range of field intensities and compared with existing theoretical results. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Multipole Method for the Rapid Solution of the Stationary Linearized Stokes System
Authors: Samrowski Tatiana
Published: December 2005

Here we will show how the multipole method can be used for the questions connected with the hydrodynamical potentials. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical and Stability Aspects of Non‐Newtonian Fluid Flow
Authors: Scurtu Nicoleta , Bänsch Eberhard
Published: December 2005

This paper is concerned with nonlinear rheological fluids of Oldroyd type. We present a (formal) stability analysis of the corresponding system of equations, showing stability limits on the Weißenberg number in certain cases. Moreover, we introduce a numerical method for solving the full time‐dependent Oldroyd system based on the finite element spatial discretization and on the fractional step θ‐scheme time approximation. Numerical solutions are presented for two well known benchmark problems: the lid driven cavity and the four‐to‐one planar contraction. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tuning the Acid/Base Surface Character of Carbonaceous Materials by Means of Cold Plasma Treatments
Authors: Favia Pietro , De Vietro Nicoletta , Di Mundo Rosa , Fracassi Francesco , d'Agostino Riccardo
Published: December 2005

Summary: Carbonaceous materials, in the form of flat graphite slabs and carbon black granules, are surface‐modified in radio frequency (RF, 13.56 MHz) glow discharges fed with NH3/O2 mixtures at different power values, in order to graft oxygen‐containing and/or nitrogen‐containing chemical groups. In this way, it is possible to adjust the acid/base character of the material surfaces in a predictable way, as a function of the feed composition and of the power. A plasma reactor equipped with a rotating vacuum chamber and internal glass wings is used to keep the granular materials homogeneously stirred and to modify the surface of both graphite slabs and carbon black granules. The chemical modifications have been evaluated using X‐ray photoelectron spectroscopy. Water contact angle measurements have been carried out on flat graphite, with water solutions at different pH, in order to study the acid/base character imparted to the functionalized surface. Scanning electron microscopy analysis has been performed to check the effects of plasma treatments on the morphology of the substrates.

SEM images of an untreated CB granule (left) and the same granule after 20 min of a O2‐plasma treatment (right).

magnified image

SEM images of an untreated CB granule (left) and the same granule after 20 min of a O2‐plasma treatment (right).