bluuebunny/crossref_metadata_2025_split huggingface dataset:
The predictive power of serum κ/λ ratios for discrimination between monoclonal gammopathy of undetermined significance and multiple myeloma
Authors: Bergón Enrique , Miravalles Elena , Bergón Elena , Miranda Isabel , Bergón Marta 
Published: January 2005

AbstractThe predictive power of serum κ/λ ratios on initial presentation of immunoglobulin G (IgG) or IgA monoclonal component was studied to differentiate between monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM) patients. The retrospective study involved 145 patients clinically diagnosed with monoclonal gammopathy of undetermined significance or multiple myeloma, who had serum M-protein IgG <35g/L or IgA <20g/L at M-protein detection. Serum light chains κ and λ were measured by fixed-time nephelometry. Test performance indices, predictive values and likelihood ratios were calculated according to the Weissler recommendation. MM patients were considered as diseased and MGUS patients as non-diseased in order to estimate the performance characteristics of serum κ/λ ratios. There was a statistically significant difference in κ/λ ratios distribution between both groups of patients, in both M-protein κ-type (Mann-Whitney U=168, p<0.001) and in M-protein λ-type (Mann-Whitney U=143, p<0.001). Negative likelihood ratios at threshold levels of 0.6 and 4.2 were 2.17- and 3.32-fold greater, respectively, than positive likelihood ratios, so that the predictive power of a serum κ/λ ratio within these limits is better in ruling out (negative predictive power) than ruling in disease (positive predictive power). The post-test characteristics of a serum κ/λ ratio interval between 0.6 and 4.2 in discriminating MGUS from MM in our geographic population were: sensitivity 0.96 (0.93–0.99 95%CI); specificity 0.70 (0.63–0.77); positive predictive value 0.68 (0.64–0.73); negative predictive value 0.96 (0.94–0.99); likelihood ratios (+)LR 3.23 (2.68–4.04); and (−)LR 17.16 (11.00–63.00). Thus, serum M-protein with a κ/λ ratio between 0.6 and 4.2 increases the posterior probability of MGUS from 0.60 to 0.96 in asymptomatic patients, for whom only monitoring may be suggested when the serum κ/λ ratio is within these limits.
Interference of dextran in biuret-type assays of serum proteins
Authors: Delanghe Joris R. , Hamers Nicole , Taes Youri E. , Libeer Jean-Claude 
Published: January 2005

AbstractDextran interference in biuret-type assays of total serum proteins was investigated in a Belgian National External Quality Assurance Survey with 256 participants. In vitro supplementation of therapeutic (10% Gentran 70
The late Greco-Roman and Byzantine contribution towards the evolution of laboratory examinations of bodily excrement. Part 2: sputum, vomit, blood, sweat, autopsies
Authors: Diamandopoulos Athanasios A. , Goudas Pavlos C. 
Published: January 2005

AbstractAlthough the establishment of medical laboratory institutions was a continuous process that matured only after the 16th century, several attempts had already been made to attain a diagnosis by investigating bodily excrement. In the first part of our work, published in a previous issue of this journal, we presented data on urine, sperm, menses and stools. In this paper we present data on sputum, vomit, blood, sweat, and autopsies, thus completing the list of human materials used for laboratory examinations. All the data used are extracted from codices of Late Antiquity and Byzantium and translated by us. We did not study medical texts from the other great ancestors of Western medicine, namely Arabic and Jewish writings. From the texts cited, it is apparent that the lack of technological means was no obstacle for the doctor to create an “examinational” mind, i.e., to try to correlate the macroscopic findings in the excrement with the pathophysiological mechanism that induced them, solely with the use of the senses. This not only applies to the examination of urine, as is commonly assumed, but also to many other excrements of the upper and lower orifices of the body, as well as the human body as a whole.
Tobacco Use and Cessation Among a Household-Based Sample of US Urban Men Who Have Sex With Men
Authors: Greenwood Gregory L. , Paul Jay P. , Pollack Lance M. , Binson Diane , Catania Joseph A. , Chang Jason , Humfleet Gary , Stall Ron 
Published: January 2005

Objectives. We examined tobacco use and cessation among a probability sample of urban men who have sex with men (MSM) living in 4 large US cities. Methods. Of the 2402 men who were eligible for follow-up from a previously recruited probability sample, 1780 (74%) completed tobacco surveys between January and December 1999. Results. Current smoking rates were higher for urban MSM (31.4%; 95% confidence interval [CI]=28.6%, 34.3%) than for men in the general population (24.7%; 95% CI=21.2%, 28.2%). Among MSM, 27% were former smokers. A complex set of sociodemographic, tobacco-related, and other factors were associated with cessation. Conclusions. Results support earlier reports that smoking rates are higher for MSM compared with men in the general population. Findings related to cessation underscore the need to target tobacco control efforts for MSM.
Gender Differences in Psychiatric Disorders at Juvenile Probation Intake
Authors: Wasserman Gail A. , McReynolds Larkin S. , Ko Susan J. , Katz Laura M. , Carpenter Jennifer R. 
Published: January 2005

Objective. We identified gender differences in psychiatric disorders among youths at probation intake. Methods. We measured disorders with the Voice Diagnostic Interview Schedule for Children among 991 randomly selected youths (200 girls) at probation intake in 8 Texas counties. Logistic regression analyses predicted diagnostic clusters by gender, adjusting for demographics and offense characteristics. Results. Demographic and offense characteristics explained small but interpretable and specific variance in diagnostic profile. Girls’ rates of anxiety and affective disorders were higher than boys’ (odds ratios = 0.59 and 0.32, respectively). Girls with violent offenses, compared with other groups, were 3 to 5 times as likely to report anxiety disorders. Conclusions. Among youths with conduct problems, girls demonstrated an elevated risk for co-occurring anxiety or affective disorder.
Working While Ill as a Risk Factor for Serious Coronary Events: The Whitehall II Study
Authors: Kivimäki Mika , Head Jenny , Ferrie Jane E. , Hemingway Harry , Shipley Martin J. , Vahtera Jussi , Marmot Michael G. 
Published: January 2005

Objectives. Although sick, some people take no time off work, a phenomenon called “sickness presenteeism.” This study examined the association between sickness presenteeism and incidence of serious coronary events. Methods. The analyses were based on a cohort of 5071 male British civil servants without previous myocardial infarction. Baseline screening included measurements of health status and coronary risk factors. Absence records were assessed for the 3 years subsequent to baseline screening. The outcome of interest was incident nonfatal myocardial infarction or fatal coronary heart disease (mean length of follow-up=9.1 years). Results. Seventeen percent of unhealthy employees took no absence during the 3-year follow-up. Their incidence of serious coronary events was twice as high as that of the unhealthy employees with moderate levels of sickness absenteeism (after adjustment for conventional risk factors, hazard ratio 1.97, 95% confidence interval=1.02, 3.83). Conclusions. Employers and employees should be aware of the potential harmful effects caused by sickness presenteeism.
Infant Mortality and Income in 4 World Cities: New York, London, Paris, and Tokyo
Authors: Rodwin Victor G. , Neuberg Leland G. 
Published: January 2005

Objectives. We investigated the association between average income or deprivation and infant mortality rate across neighborhoods of 4 world cities. Methods. Using a maximum likelihood negative binomial regression model that controls for births, we analyzed data for 1988–1992 and 1993–1997. Results. In Manhattan, for both periods, we found an association (.05% significance level) between income and infant mortality. In Tokyo, for both periods, and in Paris and London for period 1, we found none (5% significance level). For period 2, the association just missed statistical significance for Paris, whereas for London it was significant (5% level). Conclusions. In stark contrast to Tokyo, Paris, and London, the association of income and infant mortality rate was strongly evident in Manhattan.
Effects of Snowfalls on Motor Vehicle Collisions, Injuries, and Fatalities
Authors: Eisenberg Daniel , Warner Kenneth E. 
Published: January 2005

Objectives. We estimated the effects of snowfalls on US traffic crash rates between 1975 and 2000. Methods. We linked all recorded fatal crashes (1.4 million) for the 48 contiguous states from 1975 through 2000 to daily state weather data. For a subsample including 17 states during the 1990s, we also linked all recorded property-damage-only crashes (22.9 million) and nonfatal-injury crashes (13.5 million) to daily weather data. Employing negative binomial regressions, we investigated the effects of snowfall on crash counts. Fixed effects and other controls were included to address potential confounders. Results. Snow days had fewer fatal crashes than dry days (incidence rate ratio [IRR] = 0.93; 95% confidence interval [CI] = 0.90, 0.97), but more nonfatal-injury crashes (IRR = 1.23; 95% CI = 1.18, 1.29) and property-damage-only crashes (IRR=1.45; 95% CI=1.38, 1.52). The first snowy day of the year was substantially more dangerous than other snow days in terms of fatalities (IRR = 1.14; 95% CI=1.08, 1.21), particularly for elderly drivers (IRR=1.34; 95% CI=1.23, 1.50). Conclusions. The toll of snow-related crashes is substantial. Our results may help estimate the potential benefits of safety innovations currently proposed by meteorology and traffic safety experts.
Interpolation inh‐Version Finite Element Spaces
Authors: Apel Thomas 
Published: January 2005

AbstractInterpolation operators associate with a function an element from a finite element space. The difference between the two functions is calledinterpolation error. Estimates of the interpolation error are used for a priori and a posteriori estimation of the discretization error of finite element methods. For a priori error estimates, one can often use thenodal interpolant. To get optimal error bounds, the maximum available regularity of the solution has to be used. The situation is different for a posteriori error estimates. For the investigation of residual‐type error estimators, local interpolation error estimates for functions from the Sobolev spaceW1, 2(Ω) are needed. Such estimates can be obtained for many finite elements only forquasi‐interpolation operators, where point values of functions or derivatives are replaced in the definition of the interpolation operators by certain averaged values.This paper gives an overview of different interpolation operators and their error estimates. The discussion restricts theh‐version of the finite element method, but it includes interpolation on the basis of triangular/tetrahedral and quadrilateral/hexahedral meshes, affine and nonaffine elements, isotropic and anisotropic elements, and Lagrangian and other elements.
Coupling of Boundary Element Methods and Finite Element Methods
Authors: Stephan Ernst P. 
Published: January 2005

AbstractFor the numerical treatment of elliptic boundary value problems, the coupling of boundary element methods and finite element methods is widely used. Usually, the FEM is applied in a bounded subdomain, whereas the BEM subdomain may be unbounded, but without inhomogeneous or nonlinear material behavior. This chapter gives a survey of FE/BE coupling for elliptic interface problems with emphasis on mathematics. We concentrate on the symmetric coupling method because of its general applicability and give a priori and a posteriori error estimates. Further, we address implementational aspects such as suitable preconditioning for appropriate solvers of the Galerkin equations. As new developments, we consider a least squares coupling method with first‐order systems in the FEM domain and consider both primal and dual FE/BE coupling methods for interface problems with Signorini contact condition. Besides standard formulations, mixed FEM formulations are also considered. Applications in elasticity are discussed. We present proofs of essential theorems because we feel that these proofs are essential for understanding the mathematical aspects. We also present illustrative numerical examples and provide a list of references to the current literature.
Elastoplastic and Viscoplastic Deformations in Solids and Structures
Authors: Armero F. 
Published: January 2005

AbstractThis chapter presents a summary of some recent developments in the formulation and the numerical integration of elastoplastic and viscoplastic models of solids and structures. A brief description of the constitutive relations in these models in both the infinitesimal and finite deformation ranges is presented first. A key aspect of the elastoplastic models is the yield condition constraining the stress state to the so‐calledelastic domain, with the viscoplastic models resulting in a regularization of this unilateral constraint. This constrained character of the problem leads naturally to the traditional return‐mapping algorithms used in the numerical integration of the local plastic evolution equations. The resulting discrete equations correspond to the so‐calledclosest‐point projectionequations by which an elastic trial state is projected onto the elastic domain. The mathematical structure of these equations is studied to obtain efficient numerical techniques for their solution. In particular, the rich variational structure of the associated problem is investigated in detail. Primal and dual variational formulations are derived for the elastoplastic and viscoplastic models. Both lead to unilaterally constrained elastoplastic problems reflecting the underlying constrained physical system. Augmented Lagrangian extensions of these formulations resulting in unconstrained forms of the discrete equations, both in their primal and dual versions, are also explored. The different numerical algorithms associated with each of these formulations, referred generically as closest‐point projection (CPPM) algorithms, are presented in detail for a general plastic model, not necessarily associated.
Shakedown and Safety Assessment
Authors: Zouain Nestor 
Published: January 2005

AbstractThe main subjects of this chapter are the variational formulations for the computation of a safety factor in shakedown analysis, the numerical procedures available to implement this analysis, and an overview on the wide field of applications and conceptual extensions.In structural engineering and solid mechanics, the wordshakedown, introduced in the 1940s by W. Prager, became, since then, synonymous with elastic adaptation in the presence of variable loadings, a safe stabilized phenomenon, often due to some limited plastic deformation (or equivalently, due to the residual stress distribution associated with inelastic strains).Concerning the failure analysis of ductile structures, the termsalternating plasticityandincremental collapse, besidesplastic collapse, are also widely used to identify failure modes under variable loadings. A structure undergoesalternating plasticitywhen the fluctuating loading program produces, after any arbitrarily large time, some plastic deformation as well as a subsequent vanishing of the net plastic deformation. This induces failure due to low‐cycle fatigue. Likewise, the structure fails byincremental collapsewhen plastic deformations accumulate in the form of a compatible strain distribution that leads to excessive inelastic deformation.Shakedown analysis allows working under the realistic assumption that only the range of variable loadings is known, unlike the usual prescription of a particular loading history. That is, we deal withdirect methodsthat are based solely on the knowledge of a range of load variations (or a reference loading, in limit analysis) in this chapter. It is worth emphasizing that the differences between incremental and direct methods go beyond the computational advantages frequently obtained with the latter ones. In fact, the fundamental questions about whether or not critical loads or cycles do exist, independently from loading histories, can only be answered by the theories of direct methods.The mathematical foundations of shakedown theory strongly rest on optimization theory and the related areas of convex analysis and mathematical programming. The present chapter contains simplified derivations of the statical, kinematical, and mixed variational principles of shakedown theory by means of the basic techniques of convex analysis. Moreover, numerical procedures suitable to solve the shakedown analysis problem are discussed here in the framework of mathematical programming techniques combined with common procedures in the field of finite element methods.Applications in fundamental examples are then presented, namely, (a) a restrained block under thermo‐mechanical loadings, (b) the classical Bree problem of a tube under variable pressure and temperature, with a more realistic model and including an exact solution, (c) a plate with a circular hole subjected to variable tractions, and (d) a plate with simulated imperfections showing critical mechanisms with strongly localized deformations.
Computational Contact Mechanics
Authors: Wriggers P. , Zavarise G. 
Published: January 2005

AbstractThis paper describes modern techniques used to solve contact problems within Computational Mechanics. On the basis of a continuum description of contact, the mathematical structure of the contact formulation for finite element methods is derived. Emphasis is also placed on the constitutive behavior at the contact interface for normal and tangential (frictional) contact. Furthermore, different discretization schemes currently applied to solve engineering problems are formulated for small and finite strain problems. These include isoparametric interpolations, node‐to‐segment discretizations and also mortar and Nitsche techniques. Furthermore, several algorithms related to spatial contact search and fulfillment of the inequality constraints at the contact interface are discussed. Here, especially the penalty and Lagrange multiplier schemes are considered and also SQP‐ and linear‐programming methods are reviewed.
Computational Modeling of Forming Processes
Authors: Perić D. , Owen D. R. J. 
Published: January 2005

Abstract
This chapter discusses some of the relevant computational strategies that permit the simulation of industrial scale forming processes within realistic time frames and computational resources. The need for rigorous consideration of both theoretical and algorithmic issues is emphasized, particularly in relation to the computational treatment of finite strain elastoplastic (viscoplastic) deformation, the modeling of frictional contact conditions and element technology capable of dealing with plastic incompressibility. Practically important aspects such as adaptive mesh refinement procedures are discussed and attention is given to choice of appropriate error indicators for inelastic materials and the transfer of solution parameters between successive meshes. The role of explicit solution techniques in the simulation of large‐scale forming processes is also discussed.
Multifield Problems
Authors: Schrefler B. A. 
Published: January 2005

AbstractThis chapter deals with multifield problems with overlapping domains. A review of a series of typical problems belonging to this filed is first presented where examples of up to six overlapping fields are shown. Then the most popular solution procedures are discussed. They are either the monolithic method or methods involving some matrix partitioning. These methods are illustrated on selected model problems. The respective numerical properties and connected problems are discussed and examples are shown.
Vortex Methods
Authors: Winckelmans G. S. 
Published: January 2005

AbstractVortex methods are presented, from the fundamentals to the advanced subjects. These methods are well suited to simulating unsteady, convection‐dominated, flows (inviscid and viscous). The spectrum of applicability is thus quite large. Examples are presented in incompressible flows (unbounded flows and bluff‐body flows) and in combustion.
Incompressible Viscous Flows
Authors: Rannacher Rolf 
Published: January 2005

AbstractIn this article, we describe some approaches to the efficient numerical computation of viscous incompressible flows governed by the Navier–Stokes equations. We concentrate onlaminarflows, stationary as well as nonstationary, for Reynolds numbers of moderate size, and in general domains. The emphasis is on spatial discretization by the finite element method. We discuss the treatment of the incompressibility constraint, the time‐stepping process, techniques of error control and mesh adaptation and the solution of the resulting indefinite algebraic equations.
Blood Flow
Authors: Taylor Charles A. 
Published: January 2005

AbstractComputational methods can be used to simulate blood flow and vessel dynamics, test hypotheses of disease formation under controlled conditions, and evaluate devices that have not yet been built and treatments that have not yet been implemented. In this chapter, we review computational methods for quantifying blood flow velocity and pressure fields in human arteries. These methods include numerical solutions used to compute blood flow based on lumped parameter, linear, and nonlinear one‐dimensional and three‐dimensional models of blood flow. Computational models can be idealized or constructed from imaging data and applications include improved design of surgical procedures and patient‐specific preoperative planning.
Can specific deficits in executive functioning explain the behavioral characteristics of CHARGE syndrome: A case study
Authors: Nicholas Jude 
Published: January 2005

AbstractI present the case of a 12‐year‐old girl diagnosed with CHARGE syndrome. As an infant she had shown typical characteristics of CHARGE. Neuroimaging revealed asymmetrical ventriculomegaly. Both her teacher and parents reported academic and psychosocial problems. Neuropsychological assessment revealed significant executive dysfunction, including attention difficulties. We discuss the possible association between executive deficits and school and psychosocial problems. This case also highlights the importance of evaluating executive function in children with CHARGE, which is particularly useful in efficiently identifying needs for direct intervention. © 2005 Wiley‐Liss, Inc.