bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computational Biomechanics of Soft Biological Tissue
Authors: Holzapfel Gerhard A. 
Published: January 2005

AbstractComputational biomechanics of soft biological tissue is increasing our ability to address multidisciplinary problems of academic, industrial, and clinical importance. This article reviews parts of our current knowledge of the biomechanics of soft biological tissue, such as the arterial wall, the heart wall with the heart valves, and the ligament, as well as some of the available computational methods used to analyze them. The inherent complexities of the biological microstructure and function of the respective soft tissue are reviewed briefly, research effort related to the constitutive modeling catalogued, and a representative constitutive model for each considered soft tissue discussed in more detail. An account of residual stresses and biological processes such as growth and remodeling is provided. Finally, a few three‐dimensional finite element models that attempt to explain the integrated function of the respective soft tissue in terms of geometry, structure, and material properties are emphasized.
Stochastic Finite Element Methods
Authors: Gutiérrez Miguel A. , Krenk Steen 
Published: January 2005

Abstract
This chapter gives an overview of finite element related methods for the solution of problems in which the system has random properties. The notion of stochastic variables and fields is introduced and details are given for the normal and log‐normal distributions. Discretization methods for random fields and efficient algorithms for evaluation of the sensitivity to the random input are presented. The two dominating approximate methods for obtaining the statistical properties of the response from those of the stochastic properties of the system – the perturbation and the spectral method – are described in detail, and it is explained how statically determinate systems constitute a special case, permitting more general results. The final section deals with reliability methods, the purpose of which is to obtain the probability or a probability estimate, of a rare event, for example, failure. The methods are introduced by means of simple examples, with a view to making the text a self‐contained introduction and survey.
Boundary Integral Equation Methods for Elastic and Plastic Problems
Authors: Bonnet Marc 
Published: January 2005

AbstractThis chapter deals with formulations based on boundary integral equations (BIEs) for elastic and plastic problems. After a brief review of the basic integral identities of solid mechanics and issues associated with the singular character of the fundamental solutions, the collocation and symmetric Galerkin BIE formulations and the associated boundary element methods (BEMs) are presented, in their conventional form where the complete matrix equation is set up using numerical integration and stored. This approach being inadequate for large problem sizes, fast solution techniques are then reviewed, with emphasis on the fast multipole method. Next, BEMs in both collocation and symmetric Galerkin form are described for fracture mechanics and small‐strain elastoplasticity. The treatment of the hypersingular integrals arising in the integral representation of tractions on the crack surface or of strains at potentially plastic interior points is discussed, along with other issues. Shape sensitivity analysis techniques are also presented, based on either the direct differentiation of the primary elastic BIE or an adjoint solution. Finally, the symmetric Galerkin BIE is used to define a symmetric formulation for BEM–FEM coupling.
Multiscale and Stabilized Methods
Authors: Hughes Thomas J. R. , Scovazzi Guglielmo , Franca Leopoldo P. 
Published: January 2005

AbstractThis article presents an introduction to multiscale and stabilized methods, which represent unified approaches to modeling and numerical solution of fluid dynamic phenomena. Finite element applications are emphasized but the ideas are general and apply to other numerical methods as well. (They have been used in the development of finite difference, finite volume, and spectral methods, in addition to finite element methods.) The analytical ideas are first illustrated for time‐harmonic wave‐propagation problems in unbounded fluid domains governed by the Helmholtz equation. This leads to the well‐known Dirichlet‐to‐Neumann formulation. A general treatment of the variational multiscale method in the context of an abstract Dirichlet problem is then presented, which is applicable to advective–diffusive processes and other processes of physical interest. It is shown how the exact theory represents a paradigm for subgrid‐scale models and a posteriori error estimation. Hierarchicalp‐methods and bubble function methods are examined in order to understand and ultimately approximate the ‘fine‐scale Green's function’ that appears in the theory. Relationships among so‐called residual‐free bubbles, element Green's functions, and stabilized methods are exhibited. These ideas are then generalized to a class of nonsymmetric, linear evolution operators formulated in space–time. The variational multiscale method also provides guidelines and inspiration for the development of stabilized methods (e.g. SUPG, GLS, etc.) that have attracted considerable interest and have been extensively utilized in engineering and the physical sciences. An overview of stabilized methods for advective–diffusive equations is presented. A variational multiscale treatment of incompressible viscous flows, including turbulence is also described. This represents an alternative formulation of Large Eddy Simulation, which provides a simplified theoretical framework of LES with potential for improved modeling.
Spectral Element andhpMethods
Authors: Kirby Robert M. , Karniadakis George Em 
Published: January 2005

AbstractSpectral/hpelement methods provide high‐order discretization, which is essential in the longtime integration of advection‐diffusion systems. Here we review the main formulations for simulations of incompressible, compressible, and plasma viscous flows, and present several examples with some emphasis on moving domains. The first generation of (nodal) spectral elements was limited to relatively simple geometries and smooth solutions. However, the new generation of spectral/hpelements, consisting of both nodal and modal forms, can handle very complex geometries by using unstructured grids and can capture strong shocks by employing discontinuous Galerkin methods. New implementation approaches have also been developed on the basis of multilevel parallel algorithms that allow dynamic p‐refinement at constant wall clock time. After two decades of intense developments, spectral element and hp methods are mature and efficient to be used effectively in applications of industrial complexity. They provide the capabilities that standard finite element and finite volume methods do, but, in addition, they exhibit high‐order accuracy and error control.
DiscontinuousGalerkin Methods for Computational Fluid Dynamics
Authors: Cockburn B. 
Published: January 2005

AbstractThe discontinuous Galerkin methods are locally conservative, high‐order accurate, and robust methods that can easily handle elements of arbitrary shapes, irregular triangulations with hanging nodes, and polynomial approximations of different degrees in different elements. These properties, which render them ideal forhp‐adaptivity in domains of complex geometry, have brought them to the main stream of computational fluid dynamics. In this paper, we study the properties of the DG methods as applied to a wide variety of problems, including linear, symmetric hyperbolic systems, the Euler equations of gas dynamics, purely elliptic problems, and the incompressible and compressible Navier–Stokes equations. In each instance, we discuss the main properties of the methods, display the mechanisms that make them work so well, and present numerical experiments showing their performance.
Industrial Aerodynamics
Authors: Chalot Frédéric L. , Perrier Pierre 
Published: January 2005

AbstractThis chapter describes the use of computational fluid mechanics at Dassault Aviation. A historical perspective gives a measure of the successive giant steps that have been made over the past 30 years. A rather detailed description of industrial codes leads to a good understanding of the key numerical concepts assembled to create a powerful tool for computational aerodynamics. The fundamental issue of turbulence modeling is addressed in detail. A large range of complex applications is described to illustrate the variety of problems solved. The status of the development and application of shape optimization techniques and multidisciplinary design are finally illustrated.
Finite Element Methods for Fluid Dynamics with Moving Boundaries and Interfaces
Authors: Tezduyar Tayfun E. 
Published: January 2005

AbstractWe provide an overview of the finite element methods we developed in recent years for computation of fluid dynamics problems with moving boundaries and interfaces. This class of problems include those with free surfaces, two‐fluid interfaces, fluid–object and fluid–structure interactions, and moving mechanical components. The methods developed can be classified into two main categories: interface‐tracking and interface‐capturing techniques. Both classes of techniques are based on stabilized formulations, and determination of the stabilization parameters used in these formulations is also highlighted here. The interface‐tracking techniques are based on the deforming‐spatial‐domain/stabilized space–time (DSD/SST) formulation, where the mesh moves to track the interface. The interface‐capturing techniques were developed for two‐fluid flows. They are based on the stabilized formulation, over typically nonmoving meshes, of both the flow equations and an advection equation. The advection equation governs the time‐evolution of an interface function marking the interface location. We also describe some of the additional methods we developed to increase the scope and accuracy of these two classes of techniques. Among them are the enhanced‐discretization interface‐capturing technique (EDICT), which was developed to increase the accuracy in capturing the interface, extensions and offshoots of the EDICT, and mixed solution techniques. The overview of these techniques is supplemented by a number of numerical examples from computation of complex flow problems.
Behavior in CHARGE syndrome: Introduction to the special topic
Authors: Hartshorne Timothy S. , Hefner Margaret A. , Davenport Sandra L.H. 
Published: January 2005

AbstractChallenging behavior in children with CHARGE syndrome has been increasingly a concern of parents, educators, and health professionals. This article introduces the special topic in the American Journal of Medical Genetics on behavior in individuals with CHARGE syndrome. It provides background on CHARGE syndrome, diagnostic criteria, and the relationship of sensory and other physical deficits with both development and behavior. Four themes related to our developing understanding of behavior in CHARGE are described: children with CHARGE have behaviors different from those seen in other syndromes with or without deafblindness. The behavior they display is often very adaptive to their environment and to their own disabilities. These behaviors may be partially related to problems with arousal and self‐regulation. And, finally, all papers point to behavior as communication, especially within relationships, where it is essential for maximizing intellectual and social outcomes. © 2005 Wiley‐Liss, Inc.
Behavioral features of CHARGE syndrome (Hall–Hittner syndrome) comparison with Down syndrome, Prader–Willi syndrome, and Williams syndrome
Authors: Graham John M. , Rosner Beth , Dykens Elisabeth , Visootsak Jeannie 
Published: January 2005

AbstractCHARGE syndrome, or Hall–Hitner syndrome (HHS), has been delineated as a common syndrome that includes coloboma, choanal atresia, cranial nerve dysfunction (particularly asymmetric facial palsy and neurogenic swallowing problems), characteristic ear abnormalities, deafness with hypoplasia of the cochlea and semicircular canals, genital hypoplasia, and variable heart defects, orofacial clefting, tracheo‐esophageal fistula, renal anomalies, thymic/parathyroid hypoplasia, spine anomalies, short broad neck with sloping shoulders, and characteristic facial features. We conducted behavioral and personality assessments in 14 boys with HHS syndrome aged 6–21 years, and compared their characteristics with similar data from 20 age‐matched boys with Down syndrome (DS), 17 boys with Prader–Willi syndrome (PWS), and 16 boys with Williams syndrome (WS). We used the Reiss Profile of Fundamental Goals and Motivation Sensitivities, the Achenbach Child Behavior Checklist (CBCL), and the Aberrant Behavior Checklist (ABC). All 14 boys with HHS were legally deaf, and 10 of the 14 were also legally blind. In comparison these other syndromes, boys with HHS had behavior that resembled autistic spectrum disorder. They were socially withdrawn, lacked interest in social contact, and manifested reduced seeking of attention from others, with hyperactivity and a need to maintain order. Though the boys with HHS showed decreased social interaction, they were not as socially impaired as in classic autism. Their language was delayed due to dual sensory impairment, cranial nerve deficits, and chronic medical problems, but their language style was not abnormal (no echolalia or jargon, no scripted phrases, and no pronoun reversal). Boys with HSS appeared frustrated, but they were not aggressive, or at risk for delinquency, manifesting few stereotypic behaviors or unusual preoccupations. They did not have a restricted repertoire of activities and interests. Their behavioral features appeared to be due to dual sensory impairment affecting hearing and vision, rather than to primary autistic spectrum disorder, but successful remediation requires similar educational interventions, which are discussed herein. © 2005 Wiley‐Liss, Inc.
An epidemiological analysis of CHARGE syndrome: Preliminary results from a Canadian study
Authors: Issekutz Karina A. , Graham John M. , Prasad Chitra , Smith Isabel M. , Blake Kim D. 
Published: January 2005

AbstractCHARGE syndrome is a well‐characterized clinical diagnosis with recent data supporting a genetic etiology. A 3‐year national surveillance coordinated by the Canadian Pediatric Surveillance Program (CPSP) was started in September 2001. Physicians notified the CPSP if they had cared for individuals with CHARGE syndrome within their practice, and then completed a detailed reporting form. To date, there are 77 confirmed cases of CHARGE syndrome. The highest provincial prevalence of CHARGE syndrome in Canada was estimated at 1 in 8,500 live births. Subgroups of cases with particular clusters of anomalies were identified. In older individuals, bilateral posterior choanal atresia (BPCA) was predictive of the presence of the three other major criteria and of aortic arch anomalies. Individuals with CHARGE syndrome who demonstrated a less extensive phenotype (≤3 major criteria) were more likely to present with minor cardiovascular malformations, including small atrial or ventricular septal defects (VSD) or patent ductus arteriosus (PDA). A significant cause of morbidity was severe feeding difficulty, including problems with chewing, swallowing, and gastroesophageal reflux, which were prevalent throughout childhood. Infant mortality is high in individuals with CHARGE syndrome. However, life expectancy has improved for those surviving their first year. Increased mortality was associated with distinct cardiovascular malformations or ventriculomegaly combined with brainstem or cerebellar anomalies. From this study, revised diagnostic criteria are proposed for infants, children, and adolescents to help identify a group of individuals who represent CHARGE syndrome with more of the classical features as apposed to the boarder association. © 2005 Wiley‐Liss, Inc.
Synthesis of the selective antimuscarinic agent 4‐{[cyclohexylhydroxy(2‐methoxyphenyl)silyl]‐methyl}‐1,1‐dimethylpiperazinium methyl sulfate (o‐methoxy‐sila‐hexocyclium methyl sulfate)
Authors: Tacke Reinhold , Rafeiner Klaus , Strohmann Carsten , Mutschler Ernst , Lambrecht Günter 
Published: January 2005

AbstractThe synthesis of the potent and highly selective silicon‐containing antimuscarinic agent o‐methoxysila‐hexocyclium methyl sulfate and its corresponding tertiary amine (isolated as the dihydrochloride) is described. The quarternary compound is an o‐methoxy derivative of sila‐hexocyclium methyl sulfate, which represents one of the tools currently used in experimental pharmacology for the subclassification of muscarinic receptors. The o‐methoxy derivative, the pharmacological profile of which differs substantially from that of the nonmethoxy compound, is also recommended as a tool for the investigation of muscarinic receptor heterogeneity.
The synthesis and the crystal and molecular structure of the fungicide bis(4‐fluorophenyl)‐methyl(1H‐1,2,4‐triazol‐1‐yl‐methyl)silane (flusilazole, DPX H 6573)
Authors: Tacke Reinhold , Becker Beate , Schomburg Dietmar 
Published: January 2005

AbstractDetailed procedures (based on the respective patent literature) for the preparation of the broadspectrum fungicide flusilazole (DPX H 6573) on the laboratory scale are described using as the starting material dichloro(chloromethyl)methylsilane [CH3(ClCH2)SiCl2]. In addition, the crystal and molecular structure of flusilazole (determined by means of X‐ray diffraction analysis) is described.
Stability and microtox response of butenyltin compounds
Authors: Dooley Carol A , Testa John P 
Published: January 2005

AbstractTributenyltin bromides containing double bonds at carbon atoms C‐1, C‐2 or C‐3 were synthesized from symmetrical tetrabutenyltins. Although all three tetrabutenyltin compounds were stable, only the tributenyltin bromides with double bonds at C‐1 and C‐3 were sufficiently stable for further studies. In aqueous sodium bromide (NaBr) solution containing 1% acetone, tri‐1‐butenyltin bromide was more stable in sunlight than tri‐3‐butenyltin bromide, yet neither compound was as stable as tributyltin bromide. Stability in seawater, in the absence of ultraviolet (UV) light, was less for both tri‐1‐butenyltin bromide and tri‐3‐butenyltin bromide than for tributyltin bromide. The relative toxicities of the tributenyltin bromides were determined using a bioluminescent bacteria assay. The concentrations of tributenyltin bromides necessary to produce a toxic response were three to six times greater than for tributyltin bromide.
Synthesis and spectroscopic characterization of dimethylgermanium derivatives of dipeptides, crystal structure of dimethylgermanium glycylglycinate and in vivo effects of dimethylgermanium glycylglycinate against murine leukemia P388
Authors: Vornefeld Michael , Huber Friedo , Preut Hans , Brunner Henri 
Published: January 2005

AbstractDimethylgermanium derivatives of dipeptides, Me2GeAA (H2AA = H2glygly, H2glyala, H2glyval, H2glyleu, H2glymet) have been obtained by the reaction of Me2GeBr2 with H2AA in the presence of triethylamine. The crystal structure of Me2Geglygly has been determined by single‐crystal X‐ray diffraction. The dipeptide is tridentately coordinated to germanium, which has a distorted trigonal bipyramidal environment. From infrared and Raman data, analogous molecular structures are inferred for the other dimethylgermanium derivatives of dipeptides. 1H NMR measurements show that Me2Geglygly is completely hydrolyzed in aqueous solution to give H2glygly and (Me2Geo)x.In vivo tests with Me2Geglygly showed no toxic or antitumor activity against murine leukemia P388.
Thermal decomposition of butylindium thiolates and preparation of indium sulfide powders
Authors: Nomura Ryoki , Inazawa Shin'ji , Kanaya Kouichi , Matsuda Haruo 
Published: January 2005

AbstractThermal properties of organoindium thiolates were investigated by means of thermogravimetric (TG) and differential thermal (DT) analysis. Dibutyl‐indium propylthiolates (Bun2InSPrn, Bun2InSPri, Bui2InSPrn and Bui2InSPri) decomposed up to 280°C along with an exothermic DT peak and gave indium(I) sulfide (InS) powders. Although the arylthiolate Bun2InSPh also afforded InS powders, it decomposed at a slightly higher temperature. In contrast, the dithiolate and the dithiocarbamate complexes [BunIn(SPri)2 and In (S2CNBu2)3] gave indium(III) sulfide (In2S3) powders.
The determination of tetra‐alkyllead and ionic alkyllead compounds in seafood
Authors: Forsyth D S , Iyengar J R 
Published: January 2005

AbstractExtraction methodologies were developed for tetra‐alkyllead and ionic alkyllead compounds in seafood. Tetra‐alkylleads were extracted with n‐hexane after the samples had been enzymatically hydrolyzed. The ionic alkylleads were complexed with diphenylthiocarbazone (dithizone) at pH 8 and 9 from enzymatically hydrolyzed samples to optimize recovery. The dithizone extracts were butylated prior to analysis by gas chromatography–atomic absorption spectrometry (GC AA). Instrumental detection limits ranged between 1.6 and 2.3 pg lead. Application to a limited number of seafood samples indicated the possible presence of trace amounts (ca 1 ng g−1) of trimethyllead in some samples. No other alkylleads were detected.
Spindle‐inhibiting effects of organotin compounds. II. Induction of chromosomal supercontraction by di‐ and tri‐alkyl and ‐aryl compounds
Authors: Jensen Klaus Gjervig , Andersen Ole , Rønne Mogens 
Published: January 2005

AbstractSpindle‐inhibiting effects of chemical compounds may be studied indirectly by quantitation of chromosomal contraction. The effects of the trimethyltin (TMT), dimethyltin (DMT), tributyltin (TBT), dibutyltin (DBT), triphenyltin (TPhT) and diphenyltin (DPht) moieties as the chloride on chromosomal contraction was studied by measurement of the average length of chromosome No. 1 from asynchronous cultures of human peripheral lymphocytes. TMT, TBT, TPhT and DPhT appear to be very strong inducers of chromosomal supercontraction, indicating that these compounds conceivably are spindle inhibitors, whilst DMT and DBT seem to be ineffective. The different effects of aryl versus alkyl and trivalent versus divalent organic substituents of tin on chromosome length may relate to different modes of action.