bluuebunny/crossref_metadata_2025 huggingface dataset:
Stretch Enhances Contraction of Bovine Coronary Arteries via an NAD(P)H Oxidase–Mediated Activation of the Extracellular Signal–Regulated Kinase Mitogen-Activated Protein Kinase Cascade
Authors: Oeckler Richard A. , Kaminski Pawel M. , Wolin Michael S.
Published: February 2003

This study examines the effects of an increase in passive stretch in endothelium-removed bovine coronary artery on oxidant-induced changes in force generation. Increasing passive stretch on the arterial segments from 5 to 20 g for 20 minutes caused a subsequent increase (
P
<0.05) in force generation to 30 mmol/L KCl or 0.1 μmol/L serotonin compared with the prestretch control response. Also associated with the passive stretch were increases in superoxide detection by lucigenin and a selective increase in extracellular signal–regulated kinase (ERK) mitogen-activated protein (MAP) kinase phosphorylation measured by Western analysis. The stretch-induced increase in force generation was eliminated by inhibition of the ERK pathway by the MEK inhibitor PD98059 but not by inhibitors of the p38 MAP kinase pathway (SB202190) or c-Jun N-terminal protein kinase pathway (SP200169). Additionally, stretch-induced increases in both ERK phosphorylation and force generation were attenuated by inhibition of tyrosine kinases (genistein), src (PP2), and specific sites on the epidermal growth factor receptor (EGFR) (AG1478). Probes for oxidant signaling, including NAD(P)H oxidase inhibitors (diphenyliodonium and apocynin) or enhancement of peroxide consumption (ebselen) but not inhibition of xanthine oxidase (allopurinol), attenuated the effects of stretch on both ERK phosphorylation and force generation. Furthermore, stretch caused an increase in EGFR phosphorylation and cytosolic to membrane translocation of the p47phox NAD(P)H oxidase subunit. Hydrogen peroxide also elicited contraction through EGFR phosphorylation and ERK. In summary, stretch seems to enhance force generation via ERK signaling through an EGFR/src-dependent mechanism activated by peroxide derived from a stretch-mediated activation of the NAD(P)H oxidase, a response that may contribute to hypertensive alterations in vascular reactivity.
Oxidized LDL Promotes Peroxide-Mediated Mitochondrial Dysfunction and Cell Death in Human Macrophages
Authors: Asmis Reto , Begley Jim G.
Published: February 2003

Several studies suggest that macrophage death and subsequent lysis contribute to the development of advanced atherosclerotic lesions. Although oxidized LDL (OxLDL) is thought to contribute to lesion formation and induces macrophage apoptosis, the mechanisms underlying macrophage lysis have not been well defined. To determine if induction of apoptosis in human macrophages also promotes cell lysis, we studied caspase-3 activation by OxLDL and activating anti-Fas antibodies. We found that Fas-induced activation of caspase-3 does not promote macrophage lysis and caspase-3 activation is not required for OxLDL-induced macrophage lysis. OxLDL induces the formation of peroxides, but not superoxide, and decreases mitochondrial membrane potential. Scavengers of peroxyl radicals restore mitochondrial membrane potential and prevent macrophage lysis, implicating peroxyl radicals in both mitochondrial dysfunction and macrophage lysis induced by OxLDL. We conclude that macrophage death induced by OxLDL results in cell lysis, but it does not require activation of Fas or caspase-3. The full text of this article is available at http://www.circresaha.org.
Cyclic Variation of Intracellular Calcium
Authors: Lakatta Edward G. , Maltsev Victor A. , Bogdanov Konstantin Y. , Stern Michael D. , Vinogradova Tatiana M.
Published: February 2003

While a diversity of cell types and distribution within the sinoatrial node and cell-cell interactions add complexity to a complete elucidation of the heart’s pacemaker function, it has become clear that cyclic variation of submembrane [Ca
2+
] and activation of the Na
+
-Ca
2+
exchanger during diastolic depolarization (DD) act in concert with ion channels to confer on sinoatrial node cells (SANCs) their status of dominance with respect to pacemaker function. Studies using confocal microscopy indicate that subsarcolemmal Ca
2+
release via ryanodine receptors occurs not only in response to the action potential (AP) upstroke, but also during the DD, and this is augmented by β-adrenergic receptor (β-AR) stimulation. Spontaneous APs simulated by mathematical SANC models beat at a faster rate when this subsarcolemmal Ca
2+
waveform measured under β-AR stimulation is introduced into the modeling scheme. Thus, in future investigation of pacemaker functioning in health, disease, and disease therapies the “bar ought to be raised” to embrace the impact of cyclic variation in submembrane [Ca
2+
] on pacemaker function. The full text of this article is available at http://www.circresaha.org.
Liposomal Delivery of Heat Shock Protein 72 Into Renal Tubular Cells Blocks Nuclear Factor-κB Activation, Tumor Necrosis Factor-α Production, and Subsequent Ischemia-Induced Apoptosis
Authors: Meldrum Kirstan K. , Burnett Arthur L. , Meng Xianzhong , Misseri Rosalia , Shaw Matthew B.K. , Gearhart John P. , Meldrum Daniel R.
Published: February 2003

Heat shock protein 72 (HSP72) is a stress-inducible protein capable of protecting a variety of cells from toxins, thermal stress, and ischemic injury. The cytoprotective role and mechanism of action of HSP72 in renal cell ischemic injury remain unclear. To study this, HSP72 was introduced (liposomal transfer) or induced (thermal stress, 43°C×1 hour) in renal tubular cells (LLC-PK1) with Western blot confirmation. Cells were subjected to simulated ischemia 24 hours after liposomal HSP72 transfer or thermal stress, and the effect of HSP72 on nuclear factor-κB (NF-κB) activation (electrophoretic mobility shift assay and immunohistochemistry), IκBα production (Western blot), postischemic tumor necrosis factor-α (TNF-α) production (RT-PCR), and apoptosis (TUNEL assay) were determined. In separate experiments, the role of TNF-α in apoptosis was determined (anti-TNF-α neutralizing antibody). Results demonstrated that both liposomal transfer of HSP72 and thermal induction of HSP72 prevented NF-κB activation and translocation, TNF-α gene transcription, and subsequent ischemia-induced renal tubular cell apoptosis. Furthermore, TNF-α neutralization also inhibited ischemia-induced renal tubular cell apoptosis. These results indicate that liposomal delivery of HSP72 inhibits ischemia-induced renal tubular cell apoptosis by preventing NF-κB activation and subsequent TNF-α production. Further elucidation of the mechanisms of HSP-induced cytoprotection may result in therapeutic strategies that limit or prevent ischemia-induced renal damage.
Near-Field Virtual Audio Displays
Authors: Brungart Douglas S.
Published: February 2003

Although virtual audio displays are capable of realistically simulating relatively distant sound sources, they are not yet able to accurately reproduce the spatial auditory cues that occur when sound sources are located near the listener's head. Researchers have long recognized that the binaural difference cues that dominate auditory localization are independent of distance beyond 1 m but change systematically with distance when the source approaches with in 1 m of the listener's head. Recent research has shown that listeners are able to use these binaural cues to determine the distances of nearby sound sources. However, technical challenges in the collection and processing of near-field head-related transfer functions (HRTFs) have thus far prevented the construction of a fully functional near-field audio display. This paper summarizes the current state of research in the localization of nearby sound sources and outlines the technical challenges involved in the creation of a near-field virtual audio display. The potential applications of near-field displays in immersive virtual environments and multimodal interfaces are also discussed.
Ventilatory control in patients with sleep apnoea and left ventricular dysfunction: comparison of obstructive and central sleep apnoea
Authors: Wilcox I. , McNamara S.G. , Dodd M.J. , Sullivan C.E.
Published: February 2003

Sleep apnoea is common in patients with heart failure. While most patients have central sleep apnoea (CSA), a minority have obstructive sleep apnoea (OSA). The pathophysiology of CSA is not well understood. We hypothesized that central chemosensitivity would be an important pathophysiological factor in patients with CSA, and not in OSA. The aim of this study was to compare ventilatory responses between patients with CSA and those with OSA.

Acute ventilatory responses to eucapnic hypoxia and hyperoxic hypercapnia were measured during wakefulness in 34 patients (33 males and one female, aged 59±8 yrs (mean±sd)), with stable medically-treated left ventricular dysfunction (LVD) and sleep apnoea (18 OSA and 16 CSA).

Patients with CSA had a decreased awake end-tidal carbon dioxide tension (4.1± 0.5 kPa), increased ventilatory response to carbon dioxide (0.65±0.43 L·min-1·kPaPCO2-1), and eucapnic hypoxic responses in the normal range (0.6±0.4 L·min-1/% fall in arterial oxygen saturation (Sa,O2)). In contrast, patients with OSA had normal endtidal carbon dioxide tension (4.9±0.5 kPa), and normal ventilatory responses to hypercapnia (0.29±0.16 L·min-1·kPaPCO2-1) and hypoxia (0.5±0.5 L·min-1/% fall inSa,O2).

These findings suggest that augmented chemosensitivity to hypercapnia may be an important factor in the pathophysiology of central sleep apnoea in patients with heart failure.
Neutrophil elastase: alpha-1-proteinase inhibitor complex in serum and bronchoalveolar lavage fluid in patients with pulmonary fibrosis
Authors: Yamanouchi H , Fujita J , Hojo S , Yoshinouchi T , Kamei T , Yamadori I , Ohtsuki Y , Ueda N , Takahara J
Published: February 2003

It was hypothesized that neutrophil elastase released from activated neutrophils may play an important role in the pathogenesis of pulmonary fibrosis. In the present study, we measured the neutrophil elastase:alpha-1-proteinase inhibitor complex (E-PI) in serum and bronchoalveolar lavage fluid (BALF) in 26 patients with pulmonary fibrosis and evaluated the correlation between E-PI levels and several parameters. E-PI levels in serum of patients with pulmonary fibrosis (635.8+/-112.0 ng.mL(-1)) were significantly elevated compared to normal nonsmokers (122.0+/-4.0 ng.mL(-1)) as well as normal smokers (132.8+/-8.4 ng.mL(-1)) (p<0.01). E-PI levels in serum significantly correlated with hepatocyte growth factor (HGF) levels in serum, C-reactive protein (CRP), and negatively correlated with arterial oxygen tension (Pa,O2), and arterial carbon dioxide tension (Pa,CO2). E-PI/albumin levels in BALF significantly correlated with HGF/albumin levels in BALF, lactate dehydrogenase (LDH)/albumin in BALF, total number of inflammatory cells (alveolar macrophages and neutrophils) in BALF, and several markers derived from epithelial cells in BALF. Our data demonstrated: 1) neutrophil elastase:alpha-1-proteinase inhibitor complex in serum increased in patients with pulmonary fibrosis; and 2) neutrophil elastase:alpha-1-proteinase inhibitor complex in serum and bronchoalveolar lavage fluid correlated with clinical parameters in pulmonary fibrosis. These results suggest that neutrophil elastase may play a significant role in the process of lung injury in pulmonary fibrosis.
Superoxide anion production by monocytes of corticosteroid-treated asthmatic patients
Authors: Majori M , Vachier I , Godard P , Farce M , Bousquet J , Chanez P
Published: February 2003

Reactive oxygen species play an important role in promoting inflammation. Blood monocytes have been described to release higher amounts of superoxide anion in uncontrolled and untreated asthmatics. Corticosteroids are widely used in asthma, but little is known about their molecular mechanism of action. The aim of our study was to analyse the ex vivo effect of corticosteroid treatments on superoxide anion release by blood monocytes. Superoxide anion release was measured by a spectrophotometric method based on the superoxide dismutase (SOD) -inhibitable reduction of ferricytochrome C by blood monocytes from untreated patients and asthmatics treated with i.v., inhaled and oral corticosteroids. Monocytes from uncontrolled and untreated asthmatics, released high amounts of superoxide anions. After short-term treatment with i.v., corticosteroids, this release was found to decrease significantly (1.410 versus 0.340 nM, p<0.05). Cells from asthmatics who had undergone long-term treatment with inhaled or oral steroids presented low amounts of superoxide anion production, with a significant difference as compared to untreated asthmatics (0.375 nM p<0.01 and 0.620 nM p<0.02 respectively). In general, patients with controlled asthma (treated with short-term oral steroids, or with long-term inhaled steroids) released lesser amounts of superoxide anion than uncontrolled and untreated asthmatics. In the case of steroid-dependent asthmatics there was no difference between patients with a controlled or uncontrolled disease.
Functional evaluation of the lung resection candidate
Authors: Bolliger CT , Perruchoud AP
Published: February 2003

Advances in operative technique and perioperative care have considerably reduced surgical morbidity and mortality after pulmonary resections. Various single and combined parameters of functional operability have been proposed to assess the surgical risk. Pulmonary function tests adequately assess the pulmonary risk, and baseline or stress electrocardiography, echocardiography and nuclear cardiac studies assess the cardiac risk. Patients with normal or only slightly impaired pulmonary function (forced expiratory volume in one second (FEV1) and transfer factor of the lung for carbon monoxide (TL,CO) > or = 80% of predicted) and no cardiovascular risk factors can undergo pulmonary resections up to a pneumonectomy without further investigation. For others, exercise testing, pulmonary split-function studies, or a combination of these two methods are recommended. Exercise testing, most frequently performed as a symptom-limited test with the measurement of maximal oxygen uptake (V'O2,max), assesses both the pulmonary and cardiovascular reserves. A V'O2,max of <10 mL.kg(-1).min(-1) is generally considered prohibitive for any resection, a value of >20 mL.kg(-1).min(-1) or >75% of predicted normal, safe for major resections. Split-function studies are radionuclide-based estimations of the predicted postoperative (ppo) values of various parameters. The currently used ppo-parameters are FEV1-ppo, TL,CO-ppo and, most recently, V'O2,max-ppo. Suggested cut-off values for safe resection are: for FEV1-ppo and TL,CO-ppo > or = 40% pred; and for V'O2,max > or = 35% pred, combined with an absolute value of > or = 10 mL.kg(-1).min(-1). The lowest acceptable ppo-values will still have to be established by additional prospective studies. In the long-term, resections involving not more than one lobe usually lead to an early functional deficit followed by later recovery. The permanent functional loss in pulmonary function is small (< or = 10%) and exercise capacity is only slightly reduced or not at all. Pneumonectomy, on the other hand, leads to an early permanent loss of about 33% in pulmonary function and 20% in exercise capacity. Thus, pulmonary function tests alone overestimate the functional loss after lung resection.
Experimental models for studying mucociliary clearance
Authors: King M
Published: February 2003

Respiratory tract mucus is a viscoelastic gel, the rheological properties of which are determined mainly by its content of mucous glycoproteins and water. The rheology and quantity of mucus, in concert with ciliary factors, are the major determinants of mucociliary clearance. A wide range of animal models for studying the secretion and clearance of mucus are available. Ex vivo models, such as the frog palate or excised bovine trachea, provide direct, meaningful data regarding the clearability of mucus. Rodent models of chronic bronchitis, based on irritant gas or cigarette smoke exposure, show important features of the human condition in a relatively short time. The rheological characterization of mucus is made difficult by the small quantities obtainable, particularly from normal animals. Large animal models, such as the dog or sheep, although more expensive, offer many advantages, such as the ability to carry out long-term serial measurements, and to make integrated measurements of the clearance of mucus, ciliary function, epithelial ion transport, and the rheology of mucus in the same preparation.
An unusual presentation of secondary pleural hydatidosis
Authors: Aguilar X , Fernandez-Muixi J , Magarolas R , Sauri A , Vidal F , Richart C
Published: February 2003

Although pleural involvement is relatively common in cystic hydatid disease, one of the rarest and least known complications is secondary pleural hydatidosis. We report the case of a patient who presented with polycystic secondary pleural hydatidosis 4 yrs after treatment for a pyopneumothorax caused by rupture of a pulmonary cyst near the pleural space. Due to the coexistence of severe chronic obstructive pulmonary disease, surgery was ruled out. The patient was treated with albendazole, with a favourable outcome.
Quantification of shallow water quality parameters by means of remote sensing
Authors: Liu Yansui , Islam Md Anisul , Gao Jay
Published: February 2003

Quantification of quality parameters of inland and near shore waters by means of remote sensing has encountered varying degrees of success in spite of the high variability of the parameters under consideration and limitations of remote sensors themselves. This paper comprehensively evaluates the quantification of four types of water quality parameters: inorganic sediment particles, phytoplankton pigments, coloured dissolved organic material and Secchi disk depth. It concentrates on quantification requirements, as well as the options in selecting the most appropriate sensor data for the purpose. Relevant factors, such as quantification implementation and validation of the quantified results are also extensively discussed. This review reveals that the relationship between in situ samples and their corresponding remotely sensed data can be linear or nonlinear, but are nearly always site-specific. The quantification has been attempted from terrestrial satellite data largely for suspended sediments and chlorophyll concentrations. The quantification has been implemented through integration of remotely sensed imagery data, in situ water samples and ancillary data in a geographic information system (GIS). The introduction of GIS makes the quantification feasible for more variables at an increasingly higher accuracy. Affected by the number and quality of in situ samples, accuracy of quantification has been reported in different ways and varies widely.
LiDAR remote sensing of forest structure
Authors: Lim Kevin , Treitz Paul , Wulder Michael , St-Onge Benoît , Flood Martin
Published: February 2003

Light detection and ranging (LiDAR) technology provides horizontal and vertical information at high spatial resolutions and vertical accuracies. Forest attributes such as canopy height can be directly retrieved from LiDAR data. Direct retrieval of canopy height provides opportunities to model above-ground biomass and canopy volume. Access to the vertical nature of forest ecosystems also offers new opportunities for enhanced forest monitoring, management and planning.
A study on occupant neck injury in rear end collisions
Authors: Lee J-W , Yoon K-H , Park G-J
Published: February 2003

The stiffness of the automobile seat back mostly affects neck injuries in rear end collisions. The effects of the stiffness have been experimentally investigated. A sled simulator was utilized with varying speeds and fixed stiffness. Another simulation was performed with a fixed speed and varying stiffness. A stopper was installed behind the seat back to keep a certain stiffness. The neck injuries for various cases are calculated equations from industrial standards. Using the results of the test, the effect of seat back stiffness in minimizing occupant neck injury in rear end collisions is discussed.
Cars and the environment: A new approach to assessment through ISO 14001 certification of the car process
Authors: Orecchini F , Sabatini D
Published: February 2003

To change the negative effect of traffic increase and to diminish noxious pollutant emission and environmentally harmful consequences of the car's life cycle, innovative tools and radically changed approaches are needed. The present proposal of assessing the car and its environmentally related technological and functional factors as part of the entire mobility production process shows the applicability of ISO 14001 standards to the entire car process and could be a concrete aid to reaching the current European and international objectives and strongly encouraging environmentally friendly car design, manufacturing and lifestyles. The car influences the environment during every stage of its life cycle. This paper analyses and demonstrates the real possibility of certifying, through ISO 14001 standards, instead of an industrial site or organization, a car process. The car process is the part of the mobility production process implemented in car use. Environmental management systems (EMSs) have been developed to improve the environmental performance of organizations towards the diffusion of sustainability in industrial production. The ISO 14000 series of international standards are the most important reference for eco-management of any type of organization. The two target groups involved in the car process environmental certification procedures set are manufacturers/suppliers on the one hand, interested in environmentally compatible new markets and products, and clients/users on the other hand, interested in testing benefits and problems of the EMS set-up and general environmental sustainability behaviours. The car model analysed for the case study application is the Toyota Prius, from the environmental point of view one of the best on the market, precursor model of the next-generation electric hybrid vehicles.
A unique design method for wheel profiles by considering the contact angle function
Authors: Shen G , Ayasse J. B. , Chollet H , Pratt I
Published: February 2003

This paper develops a target-oriented method for the design of railway wheel profiles. The design methodology makes use of a unique inverse method. This employs contact angles and rail profile information. A computer program based on this method has also been built and is validated by way of an example. This is an example of an implementation for an independent wheelset.
Significance‐testing the validity of idiographic methods: A little derangement goes a long way
Authors: Evans Chris D. H. , Hughes John , Houston Julia
Published: February 2003

We present an experimental design for validating idiographic data and the mathematical basis for subjecting this to statistical hypothesis testing. The method involves matching descriptions of four or more objects to the people from which they arose. If four or more can be matched, this is unlikely (p < 0.05) to have arisen by chance alone and the null hypothesis that the data communicate no information can be rejected. This criterion score of 4 is sufficient for statistical significance regardless of the total number of objects on which matching was attempted. The mathematics of this somewhat counterintuitive result is given, and we argue that this method is of value in validating idiographic data. Its relationship with the ‘method of mismatched cases’ is discussed.
Object relocation task: An exact test of significance with credit for partial knowledge
Authors: Gillett Raphael
Published: February 2003

The object relocation paradigm is used to assess spatial memory in cognitive, developmental and clinical neuropsychological contexts. A number of different objects are displayed for a period of time in a particular spatial environment, such as a room, a desktop, or a computer screen. The objects are then cleared away, and the subject is asked to replace them in their former locations. In this paper, a simple measure of individual performance on the task that gives equal credit for near misses and correct responses is presented, and an exact small‐sample test of significance for the measure is developed using rook methodology. A weighted‐credit test of spatial performance is also presented. Computational examples are provided to illustrate the methods.
Estimating the covariance function with functional data
Authors: Lee Sik‐Yum , Zhang Wenyang , Song Xin‐Yuan
Published: February 2003

This paper describes a two‐step procedure for estimating the covariance function and its eigenvalues and eigenfunctions in situations where the data are curves or functions. The first step produces initial estimates of eigenfunctions using a standard principal components analysis. At the second step, these initial estimates are smoothed via local polynomial fitting, with the bandwidth in the kernel function being selected by a data‐driven procedure. The results of a simulation study and three real examples are presented to illustrate the performance of the proposed methodology.
A tandem random walk model of the SAT paradigm: Response times and accumulation of evidence
Authors: Nikolić Danko , Gronlund Scott D.
Published: February 2003

The speed‐accuracy trade‐off (SAT) paradigm forces participants to trade response speed for information accuracy by presenting them with a response signal at variable times after the onset of processing to which they must give an immediate response (within 300 ms). The processes that underlie the paradigm, especially those affecting response times, are not completely understood. Also, the extent to which the paradigm might affect the evidence accumulation process is still unclear. By testing several different sets of assumptions, we present a random walk model for the SAT paradigm that qualitatively explains both accuracy and response time data. The model uses a tandem random walk, with two possible continuations in a second phase which begins after the response signal. If a boundary is not reached during phase one, the walk transfers the current sum (relative to the size of the boundaries) from phase one to phase two in the form of bias, with drift rate equal to zero. If, however, a boundary is reached in phase one, the second phase starts from zero (no bias) with a strong drift rate towards the previously reached boundary. The model also incorporates a psychological refractory period: a delay in the onset of a second task when two tasks are presented in close succession. The model is consistent with the idea that information about the evidence accumulation rate is not contaminated by the paradigm.
A mixture model approach to indexing rater agreement
Authors: Schuster Christof
Published: February 2003

Raters are an important potential source of measurement error when assigning targets to categories. Therefore, psychologists have devoted considerable attention to quantifying the extent to which ratings agree with each other. Two main approaches to analysing rater agreement data can be distinguished. While the first approach focuses on the development of summary statistics that index rater agreement, the second models the association pattern among the observers' ratings. With the modelling approach three groups of models can be distinguished: latent class models, simple quasi‐symmetric agreement models, and mixture models. This paper discusses a class of mixture models that is defined by its characteristic of having a quasi‐symmetric log‐linear representation. This class of models has two interesting properties. First, the simple quasi‐symmetric agreement models can be shown to be members of this class. Therefore, the results of a rater agreement analysis based on a simple quasi‐symmetric agreement model may be interpreted in the mixture model framework. Second, since the mixture models readily provide a familiar measure of rater reliability, it is possible to obtain a model‐based estimate of rater reliability from the simple quasi‐symmetric agreement models. The suggested class of mixture models will be illustrated using data from a persuasive communication study in which three raters classified respondents on the basis of their elicited cognitive responses.
High‐breakdown estimation of multivariate mean and covariance with missing observations
Authors: Cheng Tsung‐Chi , Victoria‐Feser Maria‐Pia
Published: February 2003

We consider the problem of outliers in incomplete multivariate data when the aim is to estimate a measure of mean and covariance, as is the case, for example, in factor analysis. The ER algorithm of Little and Smith which combines the EM algorithm for missing data and a robust estimation step based on an M‐estimator could be used in such a situation. However, the ER algorithm as originally proposed can fail to be robust in some cases, especially in high dimensions. We propose here two alternatives to avoid the problem. One is to combine a small modification of the ER algorithm with a so‐called high‐breakdown estimator as the starting point for the iterative procedure, and the other is to base the estimation step of the ER algorithm on a high‐breakdown estimator. Among the high‐breakdown estimators which are actually built to keep their robustness properties even if the number of variables is relatively large, we consider here the minimum covariance determinant estimator and the t‐biweight S‐estimator. Simulated and real data are used to compare and illustrate the different procedures.
Techniques for oblique factor rotation of two or more loading matrices to a mixture of simple structure and optimal agreement
Authors: Lorenzo‐Seva Urbano , Kiers Henk A. L. , ter Berge Jos M. F.
Published: February 2003

Three techniques are proposed for oblique rotation of two or more loading matrices to a mixture of simple structure and optimal agreement. The three techniques, consensus direct oblimin, consensus promin and consensus simple target rotation, are compared to existing techniques and to each other, using artificial and real data. When agreement between solutions can be expected, the new techniques appear to be more useful than oblique rotation of each of the loading matrices separately. Consensus direct oblimin achieved the best results in terms of ‘agreement between simple structures’; consensus promin was the technique that best recovered the underlying simple loading matrix; and consensus simple target rotation seemed to give an interesting compromise between agreement and simple structure, focusing a little more on simplicity than consensus direct oblimin.
When expertise backfires: Contrast and assimilation effects in persuasion
Authors: Bohner Gerd , Ruder Markus , Erb Hans‐Peter
Published: February 2003

It was proposed that source cues bias message processing in a direction opposite to cue valence if message content violates cue‐based expectancies (contrast hypothesis), but consistent with cue valence if message content is ambiguous (bias hypothesis). In line with these hypotheses, students (N = 123) reported less favourable thoughts and attitudes after reading weak arguments presented by a high (vs. low) expertise source (Expts 1 and 2), and reported more favourable thoughts after reading strong arguments presented by a low (vs. high) expertise source (Expt 2). Conversely, students' thoughts and attitudes were more (less) favourable when a high (low) expertise source presented ambiguous arguments (Expt 2). Results are discussed in relation to dual‐ vs. single‐process accounts of persuasion and models of assimilation and contrast in social judgment.
Justice and the regulation of social relations: When and why do group members deny claims to social goods?
Authors: Huo Yuen J.
Published: February 2003

When do group members withhold monetary resources, abandon procedural protections, and deny fair and respectful treatment to potential claimants? Two experiments investigated the conditions that influence judgments about others' entitlement to these three social goods. Past research suggests that exchange concerns underlie entitlement judgments such that an instrumentally beneficial relationship will promote greater support for claims to social goods. Drawing from group‐value theory (Lind & Tyler, 1988), an alternative hypothesis is proposed which suggests that entitlement judgments are motivated by concerns about preserving the core norms and values that comprise the group's identity. The findings support the group‐value hypothesis that discrimination in entitlement judgments is motivated by social identity concerns. Furthermore, this tendency to discriminate against those who challenge the group's core norms and values is moderated by the nature of the social good. The effect is strongest with regard to judgments about economic goods (money) and is attenuated with regard to judgments about procedural goods (procedural protection) and especially relational goods (fair and respectful treatment). It is suggested that the level of discrimination exhibited in the domain of procedural and relational goods is kept in check by culturally rooted beliefs that these social goods should be distributed according to egalitarian principles.
Group and person attributions in response to criticism of the in‐group
Authors: O'Dwyer Anne , Berkowitz Norman H. , Alfeld‐Johnson David
Published: February 2003

This study examined responses to criticism of the in‐group as influenced by critic's group membership and justifiability of the criticism. Participants responded to an article in which the author criticized their school. The critic was presented as a student either at the participant's own school (the in‐group) or at a college higher or lower in status than the in‐group school. The content of the criticism varied by justifiability. Results demonstrate that attributions associated with the person were greater when the critic was a fellow in‐group member, and group attributions were stronger when he or she was a student from the higher status school. Neither attribution type dominated in the low‐status out‐group condition. The content of the criticism did not influence attributions, and harmfulness of the criticism—rather than justifiability—seemed to influence other responses. Associations between type of attributions (group or person) and affective and other perceptual reactions (e.g. anger, perceived accuracy of statements) also differed by the critic's group membership. Implications for intergroup theory and communication in intergroup conflict are discussed.
Testing the social identity‐intergroup differentiation hypothesis: ‘We're not American eh!’
Authors: Lalonde Richard N.
Published: February 2003

The social identity‐intergroup differentiation hypothesis is a hotly debated issue among social identity researchers (Brown, 2000; Turner, 1999); it states that individuals having a stronger in‐group identification will perceive greater differences between their in‐group and a relevant out‐group. This study examines the importance of three factors when testing this hypothesis: the strength and salience of in‐group identification, the relevance of the out‐group for social comparison, and the relevance of the dimension of social comparison. The hypothesis was examined in relation to the national identity of a sample of Canadian students. Perceptions of the in‐group and out‐groups were measured at Time 1 (N =171). The same measures were given at Time 2 (N = 77), along with a variety of measures of social identity. It was predicted that this hypothesis would be supported when the dimension of social comparison was of high relevance and only for an important social comparison group (i.e. Americans). Finally, the ability of identity to predict differentiation at another point in time was examined in order to examine the issue of identity salience and stability. Results generally supported the hypotheses and are discussed in relation to prior research and the conceptualization of a minority identity.
Are all psychological treatments for psychosis equal? The need for CBT in the treatment of psychosis and not for psychodynamic psychotherapy
Authors: Tarrier Nicholas , Haddock Gillian , Barrowclough Christine , Wykes Til
Published: February 2003

Paley and Shapiro conclude in their review (Paley & Shapiro, 2002) that there is clear evidence that cognitive‐behaviour therapy (CBT) results in clear clinical benefits for people with schizophrenia. They argue that this research could be informed by the wider psychotherapy literature, specifically the ‘equivalence paradox’ and ‘investigator allegiance’, and that psychodynamic treatments for schizophrenia should be investigated and evaluated. We argue that their review of the literature is incomplete. We conclude that there is little evidence to support the ‘equivalence paradox’ generally, and where it is suggested, as in depression, this is most likely an artefact. In schizophrenia, there is consistent evidence that supportive psychotherapy performs poorly in treating hallucinations. We argue for improved methodology in carrying out randomized controlled trials, which would minimize bias, such as from ‘investigator allegiance’. We consider evaluation of psychodynamic psychotherapy to demonstrate equivalence to CBT as a low priority and unlikely ever to be attempted. We consider the research and clinical priorities to be the further developments of CBT and family intervention methods, which could have significant benefits for sufferers of schizophrenia and their carers.
Patients' relationship episodes and therapists' feelings
Authors: Holmqvist Rolf , Hansjons‐Gustafsson Ulla , Gustafsson Jan
Published: February 2003

The idea that psychotherapists' feelings may reflect some aspect of the content in the patients' material has long been clinically accepted but on the whole poorly systematically studied. The aim of this study was to analyse associations between relationship episodes told by patients at evaluation interviews, and therapists' subsequent feelings towards the patients. In total, 28 psychotherapies withnine psychotherapists were studied. Before therapy started, the clients were interviewed separately by the eventual therapist and a second interviewer and six relationship episodes were written down by the interviewers. During the therapy, the therapists reported their feelings on a ‘feeling checklist'after each therapy session. In a first analysis, the relationship episodes were categorized according tothe CCRT system. The results indicated only scattered associations between CCRT categories and therapistfeelings. The results were, however, difficult to interpret as it was found that the therapists' feeling patterns were quite homogenous for each therapist. Considering this, qualitative analyses were made of six therapies carried out by two therapists. These analyses revealed different but theoretically plausible patterns between the feelings attributed to the persons in the patients' relationship episodes and the therapists' subsequent feelings towards the patients. The results were interpreted as a confirmation of the purported relations between patient relationship episodes and therapist feelings, but also as pointing to the need to develop the understanding of these patterns. It seems particularly important to emphasize the importance of the therapist's own habitual feeling patterns when the impact of the patient's internalized relationship patterns on countertransference reactions is evaluated.
RE: An alternate characterization of hazard in occupational epidemiology: Years of life lost per years worked. Am J Ind Med 42:1–10, 2002
Authors: Morfeld Peter
Published: February 2003

To the Editor:

Park et al. [2002] proposed an alternate characterization of hazard in occupational epidemiology by estimating the excess years of life lost. Roughly speaking, they used an approach based on estimated numbers of excess cases among the exposed multiplied by the potential life expectancy of these cases at their age of death. Although I agree with Park et al. that occupational epidemiology should better report failure time statistics as effect measures rather than risk statistics alone [cmp. Greenland and Robins, 1988], I have to point out, with apologies, that the approach chosen by Park et al. [2002] appears to be potentially biased. A simple example based on counterfactual thinking [Maldonado and Greenland, 2002] may help to demonstrate the problems involved.
Long bone articular and diaphyseal structure in old world monkeys and apes. I: Locomotor effects
Authors: Ruff Christopher B.
Published: February 2003

The relationship between locomotor behavior and long bone structural proportions is examined in 179 individuals and 13 species of hominoids and cercopithecoids. Articular surface areas, estimated from linear caliper measurements, and diaphyseal section moduli (strengths), determined from CT scans, were obtained for the femur, tibia, humerus, radius, and ulna. Both within‐bone (articular to shaft) and between‐bone (forelimb to hindlimb) proportions were calculated and compared between taxa. It was hypothesized that: 1) species emphasizing slow, cautious movement and/or more varied limb positioning (i.e., greater joint excursion) would exhibit larger articular to cross‐sectional shaft proportions, and 2) species with more forelimb suspensory behavior would have relatively stronger/larger forelimbs, while those with more leaping would have relatively stronger/larger hindlimbs. The results of the analysis generally confirm both hypotheses. Several partial exceptions can be explained on the basis of more detailed structural‐functional considerations. Associations between locomotion and structural proportions can be demonstrated both across major groupings (hominoids and cercopithecoids) and between relatively closely related taxa, e.g., mountain and lowland gorillas, siamangs and gibbons, and Trachypithecus and other colobines. Furthermore, structure and function do not always covary with taxonomy. For example, compared to cercopithecoids, mountain gorillas have relatively larger joints, like other hominoids, but do not have relatively stronger forelimbs, unlike other hominoids. This is consistent with a locomotor repertoire emphasizing relatively slow movement but with very little forelimb suspension. Proportions of Proconsul nyanzae, Proconsul heseloni, Morotopithecus bishopi, and Theropithecus oswaldi are compared with modern distributions to illustrate the application of the techniques to fossil taxa. Am J Phys Anthropol 119:305–342, 2002. © 2002 Wiley‐Liss, Inc.
Compatibilization and property characterization of polycarbonate/polyurethane polymeric alloys
Authors: Archondouli P. S. , Kallitsis J. K. , Kalfoglou N. K.
Published: February 2003

Polymeric alloys of bisphenol A polycarbonate and a polyester‐type polyurethane were prepared over a complete composition range through melt mixing. The blends were characterized with optical and scanning electron microscopy, tensile testing, dynamic mechanical analysis, thermal analysis (differential scanning calorimetry and thermogravimetric analysis), and spectroscopic techniques (Fourier transform infrared and 1H‐NMR). A morphology examination revealed good component dispersion with 30 wt % polyurethane or less and strong interface adhesion. Dynamic mechanical analysis indicated partial component miscibility and tensile testing mechanical behavior typical of a polymeric alloy. Overall, the degree of compatibilization obtained with polycarbonate was lower than that observed previously with poly(ethylene terephthalate) or poly(butylene terephthalate). This was attributed to the lower reactivity of the aromatic OH of polycarbonate toward the isocyanate groups of polyurethane and the thermal instability of the copolymer–compatibilizer formed. Experimental evidence for the formation of the latter was provided by 1H‐NMR and dynamic mechanical analysis of selectively leached blends and by quantitative analysis results for the extraction experiments. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 612–626, 2003
Study on kinetic of natural rubber vulcanization by using vulcameter
Authors: Wang Ping‐yue , Qian Hong‐lian , Yu He‐ping , Chen Jin
Published: February 2003

The velocity of vulcameter torque change during the vulcanization of natural rubber consists of two increasing and decreasing stages. The vulcanization process in the stage of velocity increasing is not a simple reaction, and can be expressed in an equation of ln(MH − Mt) = lnA − K1(t − t0)α, which is different from the famous equation of Vut = − (aK3/K4)ln[(K2eK1t − K1eK2t)/(K2 − K1)] deduced by Coran, the value of K11/α in the former can be used as a rate constant to calculate the value of activation energy (E1) according to the Arrhenius equation. The vulcanization process in the stage of velocity decreasing consists of two first‐order reactions, and can be expressed in a kinetic equation of ln(MH − Mt) = lnB − K(t − tdis). The time (tp) at which the torque change reaches to the maximum velocity (Vm) is corresponding to the time (tdis) suggested by Coran. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 680–684, 2003
Mathematical model of charge and density distributions in interfacial polymerization of thin films
Authors: Freger V. , Srebnik S.
Published: February 2003

A general model for interfacial polymerization is proposed and solved numerically. The model takes into account diffusion and reaction of monomers, presence of unreacted functional groups on the growing polymer, and solubility effects. The formation of a polyamide film in composite separation membranes is taken as an example. The evolution of the concentrations of the polymer and unreacted moieties are followed explicitly, thus enabling the calculations of the limiting thickness and the asymmetric distribution of density and charge in the resulting film. Such knowledge is important for the prediction of rejection and transport properties of the film. The effects of reaction kinetics, monomer concentrations, and hydrodynamic conditions on the properties of the film are analyzed, and a number of analytical correlations are developed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1162–1169, 2003
Preparation and metal ion adsorption properties of the resin containing sulfonic acid groups
Authors: Rivas Bernabé L. , Ruf Beatriz
Published: February 2003

In this study, we explored a new ion exchange material synthesized by radical polymerization of styrene and 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid by using 2,2′‐azo‐isobutyronitrile (1 mol %) and divinylbenzene (0.5 mol %) as initiator and crosslinking reagents, respectively. The resin was obtained from a large excess (90%) of styrene in the feed. The yield was 72.3%. The resin was completely insoluble in water and characterized by elemental analysis, FTIR spectroscopy, scanning electron microscopy, and thermal analysis. The metal ion retention capability was investigated for Ag(I), Hg(II), Cd(II), Zn(II), Pb(II), and Cr(III). The effect of pH, time, and resin/metal ion mol ratio on the metal ion retention was studied. Selectivity of the resins from a mixture of metal ions and the maximum retention capacity at optimum pH were also determined. The recovery of the resin by using 1 and 4 M HClO4 and HNO3 demonstrated that it is possible to recover the resin above 80%. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1230–1235, 2003