bluuebunny/crossref_metadata_2025_split huggingface dataset:
Participation as an expression of patient uncertainty: An exploration of bowel cancer consultations
Authors: Sanders Tom , Skevington Suzanne 
Published: September 2004

AbstractAims: The paper explores the factors that influence patient involvement in treatment decision‐making.Methods: An observation study of 49 new consultations between oncologists and recently diagnosed bowel cancer patients was conducted at a regional cancer centre in the South West of England. The dialogue was recorded verbatim during each consultation and transcribed. The data were coded into relevant themes and analysed using the constant comparison method.Results: A significant minority (23 out of 49) of patients were involved to varying degrees in decision‐making. ‘Active’ involvement usually resulted from: (1) conflicting expectations between the doctor and the patient about the most appropriate treatment; (2) unexpected information; (3) issues related to treatment costs and benefits and (4) the lack of a clear treatment recommendation from the oncologist.Conclusion: The informed consent procedure requests that full information is provided to patients about their condition and its treatment, although there is no parallel requirement to offer an interpretation of the information. In order to help patients make optimal decisions regarding treatment, oncologists need to provide an adequate level of information as well as interpretation to patients about the pros and cons of treatment. Copyright © 2004 John Wiley & Sons, Ltd.
Defining dignity in terminally ill cancer patients: A factor‐analytic approach
Authors: Hack Thomas F. , Chochinov Harvey Max , Hassard Thomas , Kristjanson Linda J. , McClement Susan , Harlos Mike 
Published: September 2004

AbstractThe construct of ‘dignity’ is frequently raised in discussions about quality end of life care for terminal cancer patients, and is invoked by parties on both sides of the euthanasia debate. Lacking in this general debate has been an empirical explication of ‘dignity’ from the viewpoint of cancer patients themselves. The purpose of the present study was to use factor‐analytic and regression methods to analyze dignity data gathered from 213 cancer patients having less than 6 months to live. Patients rated their sense of dignity, and completed measures of symptom distress and psychological well‐being. The results showed that although the majority of patients had an intact sense of dignity, there were 99 (46%) patients who reported at least some, or occasional loss of dignity, and 16 (7.5%) patients who indicated that loss of dignity was a significant problem. The exploratory factor analysis yielded six primary factors: (1) Pain; (2) Intimate Dependency; (3) Hopelessness/Depression; (4) Informal Support Network; (5) Formal Support Network; and (6) Quality of Life. Subsequent regression analyses of modifiable factors produced a final two‐factor (Hopelessness/Depression and Intimate Dependency) model of statistical significance. These results provide empirical support for the dignity model, and suggest that the provision of end of life care should include methods for treating depression, fostering hope, and facilitating functional independence. Copyright © 2004 John Wiley & Sons, Ltd.
Antifungal properties of pristimerin and celastrol isolated from Celastrus hypoleucus
Authors: Luo Du‐Qiang , Wang Hong , Tian Xuan , Shao Hong‐Jun , Liu Ji‐Kai 
Published: September 2004

AbstractPristimerin and celastrol isolated from the roots of Celastrus hypoleucus (Oliv) Warb f argutior Loes exhibited inhibitory effects against diverse phytopathogenic fungi. Pristimerin and celastrol were found to inhibit the mycelial growth of Rhizoctonia solani Kühn and Glomerella cingulata (Stonem) Spauld & Schrenk in vitro by 83.6 and 62.6%, respectively, at 10 µg ml−1. Pristimerin showed good preventive effect (96.7% at 100 µg ml−1) and curative effect (66.5% at 100 µg ml−1) against wheat powdery mildew in vivo. For celastrol, the preventive and curative effects against wheat powdery mildew were 80.5 and 45.4%, respectively, at 100 µg ml−1. Copyright © 2004 Society of Chemical Industry
Use of the RFLP‐PCR diagnostic test for characterizing MACE and kdr insecticide resistance in the peach potato aphid Myzus persicae
Authors: Cassanelli Stefano , Cerchiari Barbara , Giannini Sara , Bizzaro Davide , Mazzoni Emanuele , Manicardi Gian Carlo 
Published: September 2004

AbstractThe peach‐potato aphid Myzus persicae (Sulzer) has developed a number of insecticide resistance mechanisms owing to the high selective pressure produced by world‐wide insecticide treatments. Knowledge of the geographical distribution and the temporal evolution of these resistant phenotypes helps to develop suitable pest‐management programs. Current understanding of the major mechanisms of resistance at the molecular level makes it possible to diagnose the presence of modified acetylcholinesterase (MACE) or knockdown resistance (kdr). This paper describes a rapid method for the identification of both resistance mechanisms in a single molecular assay by using restriction fragment length polymorphism of PCR products (RFLP‐PCR) in individual as well as pooled aphids. Copyright © 2004 Society of Chemical Industry
Electron interaction in weakly confining quantum dot potentials
Authors: Winkler Peter 
Published: September 2004

AbstractThe electronic structure of three model potentials for quantum dots has been studied. The potentials are of finite depth and spherical symmetry and have a range between 5 to 25 nm. The sequence of electronic states differs markedly from the one familiar from atomic systems. The occurrence of high angular momentum components in low‐energy excited states is particular noteworthy. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Theoretical prediction of the contact distance dependence of the electron transfer reactivity of the ClO/ClO− coupling system
Authors: Yan Shihai , Bu Yuxiang , Sun Lixiang 
Published: September 2004

AbstractOn the basis of the structures and properties of the ClO/ClO− system obtained at the density functional theory (DFT) (UB3LYP) level, employing the 6‐311+G(3df) standard basis set, the electron transfer reactivity of this system is investigated. The results indicate that there are five possible stable coupling complexes that correspond to the generous minima on the global potential energy surfaces (PES). The most stable coupling complex is planar EC4, in which there is a OO linkage with two trans‐Cl atoms. Their stabilization energies are calculated to be 20.57 (EC1: C1), 20.54 (EC2: C2, 2B), 20.69 (EC3: C1), 20.70 (EC4: Cs, 2A′), and 20.69 (EC.5: C2h, 2Bu) kcal/mol at the B3LYP/6‐311+G(3df) level; with the correction of the basis set superposition error (BSSE), the stability order of these encounter complexes is EC4 > EC.5 > EC3 > EC1 > EC2. Based on the five encounter complexes, five coupling modes are designed for the study of the electron transfer reactivity of this system. The dissociation energy curves at the activated states and the corresponding activation energies of these five coupling modes are obtained and are compared at the B3LYP/6‐311+G(3df) and MP2/6‐311+G* levels. The inapplicability of DFT methods has also been discussed in this article in predicting the energy curves, especially with a long contact distance, in which DFT methods give the abnormal behavior for the dissociations of the complexes caused by the “inverse symmetry breaking” problem. On the basis of the golden rule of the time‐dependent perturbation theory, the electron transfer reactivity and the contact distance dependence of the various electron transfer kinetics parameters (e.g., activation energy, coupling matrix element) have been analyzed at the UMP2(full)/6‐311+G* level. The electron transfer can take place over a range of contact distances, but the most effective coupling distance corresponds to only a small range. The coupling orientation analyses also indicate that the most favorable coupling mode to the electron transfer does not always correspond to the most stable encounter complex mechanism. Some highly energetic coupling modes are more favorable for the electron transfer. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Combination of direct and indirect evidence in mixed treatment comparisons
Authors: Lu G. , Ades A. E. 
Published: September 2004

AbstractMixed treatment comparison (MTC) meta‐analysis is a generalization of standard pairwise meta‐analysis for A vs B trials, to data structures that include, for example, A vs B, B vs C, and A vs C trials. There are two roles for MTC: one is to strengthen inference concerning the relative efficacy of two treatments, by including both ‘direct’ and ‘indirect’ comparisons. The other is to facilitate simultaneous inference regarding all treatments, in order for example to select the best treatment. In this paper, we present a range of Bayesian hierarchical models using the Markov chain Monte Carlo software WinBUGS. These are multivariate random effects models that allow for variation in true treatment effects across trials. We consider models where the between‐trials variance is homogeneous across treatment comparisons as well as heterogeneous variance models. We also compare models with fixed (unconstrained) baseline study effects with models with random baselines drawn from a common distribution. These models are applied to an illustrative data set and posterior parameter distributions are compared. We discuss model critique and model selection, illustrating the role of Bayesian deviance analysis, and node‐based model criticism. The assumptions underlying the MTC models and their parameterization are also discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Controlling for provider of treatment in the modelling of respiratory disease risk near cokeworks
Authors: Bottle Alex , Wakefield Jon 
Published: September 2004

AbstractThe improved quality of hospital admissions data makes them a valuable resource for researchers. However, we show that, when multiple providers of health care are considered, the provider (in this case hospital) may act like other confounders such as socio‐economic status, and hence must be controlled for. Such control is not as straightforward as for conventional confounders, however, but we describe a method that is appropriate under certain assumptions. We also describe a number of other statistical issues, such as the modelling of spatial and non‐spatial overdispersion, that arose during the use of hospital data in a study to investigate the possible adverse health effects of living in proximity to six cokeworks groups in England and Wales. The outcome data that we consider consist of hospital admissions for all respiratory disease in the under‐5s. The ecological level of the analysis is the census‐defined enumeration district, and the main (proxy) exposure measure utilised is the spatial location of the enumeration district population‐weighted centroid in relation to the cokeworks. We focus on the Teesside cokeworks group, for which we also had sulphur dioxide measurements from dispersion modelling as an alternative exposure measure. The major local providers varied appreciably in their standardized admission ratios for respiratory disease, and when provider was controlled for, the size of the observed excess risk found close to the cokeworks was decreased, making control for the provider of health care vital. However, the presence of multiple pollution sources, in addition to the usual shortcomings of ecological studies, makes interpretation difficult. Copyright © 2004 John Wiley & Sons, Ltd.
Designing follow‐up intervals
Authors: Raab G. M. , Davies J. A. , Salter A. B. 
Published: September 2004

AbstractWhen an examination is needed to determine if an event has occurred there will be a loss of efficiency in using the resulting interval‐censored data instead of the exact event times. In designing follow‐up intervals this loss for longer intervals needs to be weighed against extra visits required by shorter intervals. We obtain results to quantify this for the estimation of the median and mean survival and for covariates in parametric regression models with equally spaced examination times. Asymptotic information loss for the log‐normal and Weibull distributions are similar when comparisons are made between corresponding members of the two families. For distributions with coefficients of variation of 50 per cent or more, a choice of interval from 0.25 to 0.7 times the median is recommended. Copyright © 2004 John Wiley & Sons, Ltd.
Including a time‐of‐year effect in the analysis of a matched case‐control study
Authors: Stallard Nigel , Tombs Lee 
Published: September 2004

AbstractMotivated by a matched case‐control study to investigate potential risk factors for meningococcal disease amongst adolescents, we consider the analysis of matched case‐control studies where disease incidence, and possibly other risk factors, vary with time of year. For the cases, the time of infection may be recorded. For controls, however, the recorded time is simply the time of data collection, which is shortly after the time of infection for the matched case, and so depends on the latter.We show that the effect of risk factors and interactions may be adjusted for the time of year effect in a standard conditional logistic regression analysis without introducing any bias. We also show that, if the time delay between data collection for cases and controls is constant, provided this delay is not very short, estimates of the time of year effect are approximately unbiased. In the case that the length of the delay varies over time, the estimate of the time of year effect is biased. We obtain an approximate expression for the degree of bias in this case. Copyright © 2004 John Wiley & Sons, Ltd.
Joint modelling of multivariate longitudinal profiles: pitfalls of the random‐effects approach
Authors: Fieuws Steffen , Verbeke Geert 
Published: September 2004

AbstractDue to its flexibility, the random‐effects approach for the joint modelling of multivariate longitudinal profiles received a lot of attention in recent publications. In this approach different mixed models are joined by specifying a common distribution for their random‐effects. Parameter estimates of this common distribution can then be used to evaluate the relation between the different responses. Using bivariate longitudinal measurements on pure‐tone hearing thresholds, it will be shown that such a random‐effects approach can yield misleading results for evaluating this relationship. Copyright © 2004 John Wiley & Sons, Ltd.
A parametric survival model with an interval‐censored covariate
Authors: Langohr Klaus , Gómez Guadalupe , Muga Robert 
Published: September 2004

AbstractWe present a parametric survival model whose particularity consists in the inclusion of an interval‐censored covariate. The methodology is motivated by a study on injecting drug users in Badalona (Spain), most of whom suffered HIV infection as a result of their drug addiction. The study aims to examine the possible association between the elapsed time from first injecting drug use until HIV infection and the subsequent AIDS incubation period. Whereas the moment of HIV infection cannot be observed exactly and is therefore interval‐censored, time until AIDS onset is doubly‐censored. For the maximization of the resulting likelihood function, we use a numerical solver. Maximization is carried out by means of the mathematical programming language AMPL. Copyright © 2004 John Wiley & Sons, Ltd.
Market reactions to announcements of corporate downsizing actions and implementation strategies
Authors: Nixon Robert D. , Hitt Michael A. , Lee Ho‐Uk , Jeong Eui 
Published: September 2004

AbstractThis study examines the effects of downsizing actions and implementation strategies on market performance. While downsizing actions reduce costs, they also produce a loss of valuable human capital that can exceed the benefits resulting from the lay‐offs. In support of this argument, the results showed that downsizing had a negative effect on market returns and the effects grow increasingly negative with larger downsizing actions. However, the market reacts more positively to downsizing actions when reallocation strategies are used and to large downsizing actions when disengagement incentives are applied. The results of this research suggest the importance of carefully managing valuable resources to create positive returns. Copyright © 2004 John Wiley & Sons, Ltd.
Proinflammatory cytokines and other indications of inflammation in cervico‐vaginal secretions and preterm delivery
Authors: Torbé A. , Czajka R. 
Published: September 2004

ABSTRACTObjectivesTo compare the usefulness of evaluating cervico‐vaginal concentrations of proinflammatory cytokines (interleukin [IL]‐1α, IL‐1β, IL‐6 and IL‐8) and procalcitonin (PCT), as well as serum levels of C‐reactive protein (CRP), leucocytosis and band form granulocytes in the prediction of preterm delivery (PTD).MethodsA total of 65 pregnant women experiencing preterm labor (PTL) were enrolled in the study. Concentrations of the studied markers in women who delivered prematurely and in women who, after treatment, delivered at term were compared. Receiver operator characteristic (ROC) curve analysis was used for all study parameters.ResultsCervico‐vaginal IL‐6 and procalcitonin as well as serum CRP concentrations were higher in women who delivered prematurely than in those who delivered near term. A cervico‐vaginal IL‐6 level greater than 660 pg/ml was the best predictive value of preterm delivery (sensitivity, 50%; specificity 90%; positive predictive value [PPV], 85%; NPV, 62%; likelihood ratio, 5.17). Moreover, the area under the ROC curve of 0.75 for cervico‐vaginal IL‐6 was greater than for other markers.ConclusionAlthough cervico‐vaginal concentrations of procalcitonin and serum concentration of CRP are higher in women who deliver prematurely, only cervico‐vaginal concentration of IL‐6 is a good predictor of preterm delivery.
In vivo kinematics of the ACL during weight‐bearing knee flexion
Authors: Li Guoan , DeFrate Louis E. , Rubash Harry E. , Gill Thomas J. 
Published: September 2004

AbstractNo study has investigated the three‐dimensional morphological changes of the anterior cruciate ligament (ACL) during functional activities in vivo. The purpose of this study was to analyze the elongation, rotation (twist), and orientation of the ACL during weight‐bearing flexion in five human subjects using dual‐orthogonal fluoroscopic images and MR image‐based computer models. The ACL consistently decreased in length with flexion. At 90°, the length decreased by 10% compared to its length at full extension. The ACL twisted internally by only 20° at 30° of flexion. The ACL was oriented more vertically (approximately 60°) and slightly laterally (approximately 10°) at low flexion angles. These data on in vivo ligament elongation demonstrate that the ACL plays a more important role in lower flexion angles than at higher flexion angles during weight‐bearing flexion. These data also suggest that successful ACL reconstruction should not only restore the ligament's elongation behavior, but also its rotational and orientation characteristics, so that normal ACL biomechanics are restored. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Environmental and maternal correlates of foetal sex ratios in the African buffalo (Syncerus caffer) and savanna elephant (Loxodonta africana)
Authors: Visscher D. R. , van Aarde R. J. , Whyte I. 
Published: September 2004

AbstractMany species exhibit skewed sex ratios at birth. Here we investigate the relationships between environmental and maternal variables (as surrogates for maternal condition) and foetal sex in African buffalo Syncerus caffer and elephant Loxodonta africana of the Kruger National Park, South Africa. Using logistic regression no significant effect was found of year, maternal lactational status, maternal age, rainfall or density on foetal sex ratio. Using a subset of our data, it was also concluded that maternal body condition did not affect foetal sex ratio in buffalo. Our analyses failed to support hypotheses predicting that mothers will skew the sex ratios of their offspring in relation to their body condition. In this study, buffalo and elephant produced offspring with a sex ratio close to parity. Our results are discussed in light of the implications for testing such hypotheses in analyses of population level.
Sexual selection on male body size and assortative pairing in Gammarus pulex (Crustacea: Amphipoda): field surveys and laboratory experiments
Authors: Bollache L. , Cézilly F. 
Published: September 2004

AbstractVariation in size‐assortative pairing was studied in relation to sexual selection on male body size in the amphipod Gammarus pulex, using both transverse and longitudinal surveys of natural populations. In addition, the influence of male–male competition on size‐assortative pairing was tested in the laboratory. In both surveys, the intensity of sexual selection was positive and significant for male body size but not for females, and size‐assortative pairing was positive and significant. The magnitude of size‐assortative pairing, however, varied significantly between populations. The magnitude of size‐assortative pairing was positively correlated with the intensity of sexual selection on male body size in both surveys. In the laboratory, the strength of size‐assortative pairing decreased with decreasing male:female ratio. Taken together our results point to a role of interference competition between males in promoting patterns of size‐assortative pairing in G. pulex, although alternative explanations (i.e. female resistance) cannot be excluded.
Reproductive system of the giant squid Architeuthis in South African waters
Authors: Hoving H. J. T. , Roeleveld M. A. C. , Lipinski M. R. , Melo Y. 
Published: September 2004

AbstractThe reproductive system is described from 15 giant squid Architeuthis sp., collected between 1972 and 2002 in South African waters. Distinctive features of the male reproductive system are the long muscular terminal organ, with elaboration of the anterior end, and modification of the tips of the ventral arms, probably hectocotilization. The spermatophoric organ has a long finishing gland that extends from the base of the gill. The terminal organ is differentiated internally into three distinct parts, involved in the guidance, storage, protection, expulsion and possibly the coating of spermatophores. Length of spermatophores in the terminal organ varied considerably. Several stages of spermatophores were found, from tentative to false to fully formed spermatophores, within a single animal. Distinctive features of the female reproductive system are a mesentery surrounding the main blood vessels of the ovary and attaching the ovary to the dorsal gladius chamber, multiple branching (at least three times) of the genital aorta that supplies the developing oocytes, high potential fecundity (3.5–6.2 ± 106 oocytes), small eggs and short oviducts that suggest intermittent (extended) spawning. Large concentrations and single spermatangia were found in various places in females, indicating non‐specific deposition. The transfer of spermatophores is probably rapid, perhaps because of considerable sexual size dimorphism (at maturity, males are much smaller than females). Implants in males are probably self‐induced since the majority were found within reach of the terminal organ opening (primarily on the ventral arms in males).