bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of extracorporeal cardiopulmonary circulation on serum total and free prostate specific antigen levels
Authors: Aksoy Yılmaz , Aksoy Hülya , Ceviz Münacettin , Yavuz Balcı Ahmet , Okyar Güray , Akçay Fatih 
Published: January 2005

AbstractThe aim of this study was to investigate whether or not there is an increase in serum total and free prostate specific antigen levels (t-PSA, f-PSA) in patients with and without benign prostatic hyperplasia (BPH) undergoing extracorporeal circulation during cardiovascular bypass. The study included a total of 50 men. Of these, 35 patients underwent elective coronary artery bypass grafting with extracorporeal circulation [with (n=20, group I) and without (n=15, group II) BPH]. Another 15 patients underwent renal or ureteral surgery (group III) and served as a control group. Serum t-PSA and f-PSA levels were measured before surgery and 3h and 3days after surgery. All patients underwent urethral catheterization 24h before surgery. In groups I and II, patients had an increase in t-PSA 3h after surgery compared to baseline values (p=0.0001 and p=0.011, respectively). Also, 3days after surgery, mean t-PSA levels were higher than baseline levels (p=0.004) in group I. Serum t-PSA levels were higher at 3h than at day 3 in groups I and II (p=0.003 and p=0.02, respectively). Mean serum f-PSA levels obtained 3h after surgery were increased in both groups I and II when compared to baseline values (p=0.0001 and p=0.001, respectively). There was no significant difference between f-PSA values before and 3days after surgery in all groups. In the control group, there was no significant increase in either serum t-PSA or f-PSA levels obtained at different times. There was a modest increase in the percentage of free prostate specific antigen (% f-PSA) 3h after the operation in group II (p=0.025); the values returned to baseline within 3days. It was suggested that t-PSA and f-PSA serum levels increase due to extracorporeal cardiopulmonary circulation as a consequence of ischemic damage to the prostate. In patients with BPH, this rise may be higher than in those without BPH, because BPH patients generally have larger prostate volumes that may be more vulnerable to ischemic damage. Because f-PSA has a shorter half-life, postsurgical levels of f-PSA may not show this ischemic damage to the prostate during the late postoperative period and f-PSA appears to be cleared more rapidly than t-PSA.
Evaluation of a new automated electrochemiluminescent sex hormone-binding globulin (SHBG) immunoassay
Authors: Reynders Marijke , Anckaert Ellen , Schiettecatte Johan , Smitz Johan 
Published: January 2005

AbstractSerum sex hormone-binding globulin (SHBG) regulates the cellular bioavailability of SHBG-bound steroid hormones. Since variations in SHBG levels may affect the concentration of free, i.e., biologically active testosterone in serum, SHBG levels are commonly measured as a supplement to total testosterone determination. The recently developed electrochemiluminescence Elecsys
Prevalence of and Risk Factors for Intimate Partner Violence in China
Authors: Xu Xiao , Zhu Fengchuan , O’Campo Patricia , Koenig Michael A. , Mock Victoria , Campbell Jacquelyn 
Published: January 2005

Objectives. We estimated the prevalence of and risk factors for intimate partner violence in China. Methods. Our cross-sectional, comparative prevalence study used a face-to-face survey of randomly selected women attending an urban outpatient gynecological clinic at a major teaching hospital in Fuzhou, China. Multiple logistic regression models were used to assess risk factors for intimate partner violence. Results. Of the 600 women interviewed, the prevalence of lifetime intimate partner violence and violence taking place within the year before the interview was 43% and 26%, respectively. For lifetime intimate partner violence, partners who had extramarital affairs and who refused to give respondents money were the strongest independent predictors. For intimate partner violence taking place within the year before the interview, frequent quarreling was the strongest predictor. Conclusions. Intimate partner violence is prevalent in China, with strong associations with male patriarchal values and conflict resolutions. Efforts to reduce intimate partner violence should be given high priority in health care settings where women can be reached.
Life-Years Gained From Modern Cardiological Treatments and Population Risk Factor Changes in England and Wales, 1981–2000
Authors: Ünal Belgin , Critchley Julia A. , Fidan Dogan , Capewell Simon 
Published: January 2005

Objectives. We estimated life-years gained from cardiological treatments and cardiovascular risk factor changes in England and Wales between 1981 and 2000. Methods. We used the IMPACT model to integrate data on the number of coronary heart disease patients, treatment uptake and effectiveness, risk factor trends, and median survival in coronary heart disease patients. Results. Compared with 1981, there were 68230 fewer coronary deaths in 2000. Approximately 925415 life-years were gained among people aged 25–84 years (range: 745 195–1 138 655). Cardiological treatments for patients accounted for approximately 194145 life-years gained (range: 142505–259225), and population risk factor changes accounted for approximately 731270 life-years gained (range; 602695–879430). Conclusions. Modest reductions in major risk factors led to gains in life-years 4 times higher than did cardiological treatments. Effective policies to promote healthy diets and physical activity might achieve even greater gains.
Global Trade and Public Health
Authors: Shaffer Ellen R. , Waitzkin Howard , Brenner Joseph , Jasso-Aguilar Rebeca 
Published: January 2005

Global trade and international trade agreements have transformed the capacity of governments to monitor and to protect public health, to regulate occupational and environmental health conditions and food products, and to ensure affordable access to medications. Proposals under negotiation for the World Trade Organization’s General Agreement on Trade in Services (GATS) and the regional Free Trade Area of the Americas (FTAA) agreement cover a wide range of health services, health facilities, clinician licensing, water and sanitation services, and tobacco and alcohol distribution services. Public health professionals and organizations rarely participate in trade negotiations or in resolution of trade disputes. The linkages among global trade, international trade agreements, and public health deserve more attention than they have received to date.
Expanding Access to Antiretroviral Therapy in Sub-Saharan Africa: Avoiding the Pitfalls and Dangers, Capitalizing on the Opportunities
Authors: McCoy David , Chopra Mickey , Loewenson Rene , Aitken Jean-Marion , Ngulube Thabale , Muula Adamson , Ray Sunanda , Kureyi Tendayi , Ijumba Petrida , Rowson Mike 
Published: January 2005

We describe a number of pitfalls that may occur with the push to rapidly expand access to antiretroviral therapy in sub-Saharan Africa. These include undesirable opportunity costs, the fragmentation of health systems, worsening health care inequities, and poor and unsustained treatment outcomes. On the other hand, AIDS “treatment activism” provides an opportunity to catalyze comprehensive health systems development and reduce health care inequities. However, these positive benefits will only happen if we explicitly set out to achieve them. We call for a greater commitment toward health activism that tackles the broader political and economic constraints to human and health systems development in Africa, as well as toward the resuscitation of inclusive and equitable public health systems.
Workforce Issues in Rural Areas: A Focus on Policy Equity
Authors: Ricketts Thomas C. 
Published: January 2005

Rural communities in the United States are served by relatively fewer health care professionals than urban or suburban areas. I review the geographic distribution of 6 classes of health professionals and describe the multiple government and private policies and programs intended to affect their geographic distribution. These programs can be classified into 3 categories—coercive, normative, and utilitarian—that characterize the major policy levers used to influence practice location decisions. Health workforce policies must be normative to ensure equity for rural communities, but goals in this area can be achieved only through a balance of utilitarian and coercive mechanisms.
Thep‐Version of the Finite Element Method
Authors: Szabó Barna , Düster Alexander , Rank Ernst 
Published: January 2005

AbstractThe basic algorithmic structure and performance characteristics of thep‐version of the finite element method are surveyed with reference to elliptic problems in solid mechanics. For this class of problems, the theoretical basis of thep‐version is fully established, and a very substantial amount of engineering experience covering linear and nonlinear applications is available. It is shown thatp‐extensions on properly designed meshes make realization of exponential rates of convergence in practical computations possible and provide for the estimation and control of relative errors in terms of any data of interest. Given the growing demand for verified numerical solutions, thep‐version is expected to play an increasingly important role in the development of future finite element software products.
Boundary Element Methods: Foundation and Error Analysis
Authors: Hsiao G. C. , Wendland W. L. 
Published: January 2005

AbstractThis chapter gives an expository introduction to the Galerkin‐BEM for the elliptic boundary value problems from the mathematical point of view. Emphasis will be placed on the variational formulations of the boundary integral equations and the general error estimates for the approximate solution in appropriate Sobolev spaces. A classification of boundary integral equations will be given on the basis of the Sobolev index. The simple relations between the variational formulations of the boundary integral equations and the corresponding partial differential equations under consideration will be indicated. Basic concepts such as stability, consistency, and convergence, as well as the condition numbers and ill‐posedness, will be discussed by using elementary examples.
Finite Volume Methods: Foundation and Analysis
Authors: Barth Timothy , Ohlberger Mario 
Published: January 2005

AbstractFinite volume methods are a class of discretization schemes that have proven highly successful in approximating the solution of a wide variety of conservation law systems. They are extensively used in fluid mechanics, meteorology, electromagnetics, semi conductor device simulation, models of biological processes, and many other engineering areas governed by conservative systems that can be written in integral control volume form.This article reviews elements of the foundation and analysis of modern finite volume methods. The primary advantages of these methods are numerical robustness through the obtention of discrete maximum (minimum) principles, applicability on very general unstructured meshes, and the intrinsic local conservation properties of the resulting schemes. Throughout this article, specific attention is given to scalar nonlinear hyperbolic conservation laws and the development of high‐order accurate schemes for discretizing them. A key tool in the design and analysis of finite volume schemes suitable for discontinuity capturing is discrete maximum principle analysis. A number of building blocks used in the development of numerical schemes possessing local discrete maximum principles are reviewed in one and several space dimensions, for example, monotone fluxes, TVD discretization, positive coefficient discretization, nonoscillatory reconstruction, slope limiters, etc. When available, theoretical results concerning a priori and a posteriori error estimates are given. Further advanced topics are then considered such as high‐order time integration, discretization of diffusion terms, and the extension to systems of nonlinear conservation laws.
Mesh Generation and Mesh Adaptivity
Authors: George P. L. , Borouchaki H. , Frey P. J. , Laug P. , Saltel E. 
Published: January 2005

Abstract
In this chapter, we are concerned with mesh‐generation methods and mesh‐adaptivity issues. Many techniques are nowadays available to complete meshes of arbitrary domains for computational purposes. Planar, surface, and volume meshing have been automated to a large extent. Over the last few years, meshing activities have been focused on adaptive schemes, where the features of a solution field must be accurately captured. To this end, meshing techniques must be revisited in order to be capable of completing high‐quality meshes conforming to these features. Error estimates are therefore used to analyze the solution field at a given stage, and, on the basis of the results of the infunction they yield, adapted meshes are created before computing the next stage of the solution field. A number of novel meshing issues must be addressed, including how to construct a mesh that can adapt to what the error estimate prescribes, how to handle large‐size meshes, how to consider moving boundary problems, and so on.
Computational Visualization
Authors: Schroeder William J. , Shephard Mark S. 
Published: January 2005

AbstractVisualization is an essential part of the computational sciences. While today's complex numerical techniques produce results of unparalleled accuracy, they also produce prodigious amounts of data. To realize the true potential of this information, visualization techniques are required to efficiently convey the meaning of the data to the analyst. In this chapter, we explore basic concepts, terminology, and visualization techniques. We conclude by describing methods for integrating the results of computational analysis data with the visualization system.
Linear Algebraic Solvers and Eigenvalue Analysis
Authors: van der Vorst Henk A. 
Published: January 2005

AbstractThis chapter gives an overview of the most widely used numerical methods for the solution of linear systems of equations and for eigenproblems, including direct methods and iterative methods. Iterative methods are often used in combination with the so‐called preconditioning operators. We will give a brief overview of the various preconditioners that exist. For eigenproblems of the typeAx = λx, the QR method is discussed. The QR method is expensive for larger values ofn, and for these larger values, a number of iterative methods, including the Lanczos method, Arnoldi's method, and the Jacobi–Davidson method are shown.
Adaptive Computational Methods for Parabolic Problems
Authors: Eriksson K. , Johnson C. , Logg A. 
Published: January 2005

AbstractWe present a unified methodology for the computational solution of parabolic systems of differential equations with adaptive selection of discretization in space and time, based on a posteriori error estimates involving residuals of computed solutions and stability factors/weights, obtained by solving an associated linearized dual problem. We define parabolicity as boundedness in time (up to logarithmic factors) of a certain strong stability factor measuring theL1(L2)‐norm in time–space of the time derivative of the dual solution withL2‐normalized initial data.
Time‐Dependent Problems with the Boundary Integral Equation Method
Authors: Costabel Martin 
Published: January 2005

AbstractTime‐dependent problems that are modeled by initial‐boundary value problems for parabolic or hyperbolic partial differential equations can be treated with the boundary integral equation method. The ideal situation is when the right‐hand side in the partial differential equation and the initial conditions vanish, the data are given only on the boundary of the domain, the equation has constant coefficients, and the domain does not depend on time. In this situation, the transformation of the problem to a boundary integral equation follows the same well‐known lines as for the case of stationary or time‐harmonic problems modeled by elliptic boundary value problems. The same main advantages of the reduction to the boundary prevail: Reduction of the dimension by one, and reduction of an unbounded exterior domain to a bounded boundary.There are, however, specific difficulties due to the additional time dimension; apart from the practical problems of increased complexity related to the higher dimension, there can appear new stability problems. In the stationary case, one often has unconditional stability for reasonable approximation methods, and this stability is closely related to variational formulations based on the ellipticity of the underlying boundary value problem. In the time‐dependent case, instabilities have been observed in practice, but due to the absence of ellipticity, the stability analysis is more difficult and fewer theoretical results are available.In this article, the mathematical principles governing the construction of boundary integral equation methods for time‐dependent problems are presented. We describe some of the main algorithms that are used in practice and have been analyzed in the mathematical literature.
Buckling
Authors: Riks Eduard 
Published: January 2005

AbstractAlthough the first known solution of a buckling problem was given by the outstanding Swiss ‘natural philosopher’ Leonhard Euler (1744), buckling theory as an engineering subject is an outgrowth of a development that was established during the last century. The overview of the present knowledge regarding the computational analysis of buckling problems is here given in the context of the theory's most important historical developments.
Computational Structural Dynamics
Authors: Hulbert Gregory M. 
Published: January 2005

AbstractThis chapter presents an overview and a state‐of‐the art compilation of time integration methods for solving problems of dynamics, with a particular focus on developments that have occurred during the past 25 years. Various classifications of time integration algorithms are provided that assist the reader in understanding the many different types of numerical methods available for solving time‐dependent problems. Time integration algorithms for linear structural dynamics are reviewed thoroughly, from classical Newmark‐type schemes, to recent developments in time finite element‐based approaches. The distinction between linear and nonlinear dynamics is articulated and numerical methods developed for direct application towards solving nonlinear dynamics probems are presented. The chapter concludes with guidelines towards selecting an appropriate time integration method, along with guidelines towards choosing appropriate time step sizes.
Homogenization Methods and Multiscale Modeling
Authors: Zohdi Tarek I. 
Published: January 2005

Abstract
The relatively recent increase in computational power available for mathematical modeling and simulation raises the possibility that modern numerical methods can play a significant role in the analysis of materials possessing heterogeneous microstructure. Ideally, in an attempt to reduce laboratory expense, one would like to make predictions of a new material's behavior by numerical simulations, with the primary goal being to accelerate the trial and error laboratory development of novel high performance materials. This fact, among others, has motivated the work that will be presented in this monograph.
Damage, Material Instabilities, and Failure
Authors: de Borst René 
Published: January 2005

AbstractThis chapter begins with an overview of damage mechanics. Isotropic and anisotropic models are described, as well as the coupling to plasticity, including the algorithmic treatment. Next, the implications of strain softening, which starts at a certain level of damage accumulation, are discussed as regards important notions such as material stability and ellipticity. The consequences of loss of ellipticity in terms of grid sensitivity of computations are illustrated for static and for dynamic instabilities. Next, the important role of cohesive‐zone models is highlighted, both in its original (discrete) format, a derived smeared format and as an embedded discontinuum description. To avoid loss of ellipticity, the introduction of higher‐order continua is necessary. Various higher‐order continua incorporating damage or coupled damage‐plasticity models are discussed, including aspects of numerical implementation. Finally, the numerical implementation of cohesive‐zone models in a discrete format is considered, where attention is given to conventional interface elements as well as to approaches that exploit the partition‐of‐unity property of finite element shape functions.
Computational Modelling of Damage and Failures in Composite Laminates
Authors: Reddy J. N. , Robbins D. H. 
Published: January 2005

AbstractThis chapter provides an overview of issues that are important in finite element modeling of progressive damage and failure in fiber‐reinforced composite laminates. Topics discussed include the multiscale nature of composite laminate problems, equivalent single layer and layerwise laminate theories and models, macroscopic failure theories, computational homogenization and localization, and the application of continuum damage mechanics to composite laminate problems, with emphasis on methods that are practical for large scale analysis of composite structural components.
Identification of Material Parameters for Constitutive Equations
Authors: Mahnken R. 
Published: January 2005

Abstract
This contribution addresses various topics on parameter identification for constitutive equations on the basis of experimental data. Starting from basic characteristics of inverse problems illustrated by simple examples, four different identification methods are introduced. Then particular aspects of the least squares approach are outlined, such as optimization, local minima, sensitivity analysis, consequences of instabilities, and stochastic methods. Uniform small strain problems and nonuniform large strain problems are considered, where for the latter finite element results are incorporated into the optimization process. The examples are concerned with a perturbation technique in order to detect possible instabilities, a stochastic analysis in order to examine the uncertainty of parameter estimates, and a necking problem observed with an optical method in order to take into account nonuniform large strains during the experiment.
Fluid‐Structure Interaction Problems
Authors: Ohayon Roger 
Published: January 2005

AbstractSeveral so‐called reduced order formulations are reviewed in the case of linear vibration analysis of bounded fluid‐structure systems for low modal density situations. Compressibility effects in the fluid for interior structural‐acoustic problems, and free‐surface gravity effects, as well as for hydroelastic‐sloshing interaction problems in the case of incompressible liquids, are examined. Reduced order models leading to symmetric matrix systems are then described using static well‐posed behavior of the irrotational fluid. In this respect, the fluid‐structure boundary value local equations, expressed in terms of fluid scalar field variables for the fluid (and displacement variables for the structure), are regularized for zero‐frequency limit.