bluuebunny/crossref_metadata_2025_split huggingface dataset:
Angle‐resolved XPS study of the effect of x‐radiation on the aging of polystyrene exposed to an oxygen/argon plasma
Authors: Paynter R. W. 
Published: August 2002

AbstractPolystyrene films spin‐coated onto glass were exposed to an oxygen/argon plasma. The depth profile of the oxygen in the polystyrene surface was characterized by angle‐resolved x‐ray photoelectron spectroscopy (ARXPS) 2, 24 and 92 h following the plasma treatment. It was found that oxygen was lost from the surface over time, mainly from C O and especially O CO O groups, and that the exposure to x‐rays during the ARXPS measurement accelerated this loss. At the 92 h mark, a linear, negative correlation was found between the oxygen content of the polystyrene surface and the water contact angle. The relative merits of the three models used to interpret the ARXPS data are discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Resonance tracking ultrasonic atomic force microscopy
Authors: Kobayashi K. , Yamada H. , Matsushige K. 
Published: August 2002

AbstractWe have developed a new resonance tracking ultrasonic atomic force microscopy (UAFM) technique that measures the contact resonance frequency of a cantilever beam. The cantilever beam is vibrated at its contact resonance frequency by applying positive feedback while the tip near the end of the beam is kept in contact with the sample surface. The topographic image is acquired in normal contact mode while the contact resonance frequency is tracked by an extremely sensitive phase‐locked loop (PLL) circuit for the UAFM image. The UAFM image was obtained on a phase‐change recording medium (rewritable compact disc). The image showed a variation in the contact resonance frequency as large as 150 Hz in the groove, which probably is caused by the difference in elastic properties between the crystalline phase and the amorphous phase. Copyright © 2002 John Wiley & Sons, Ltd.
XPS and SEM characterization of wheel/workpiece interface in grinding of superalloy
Authors: Xu Xipeng , Yu Yiqing 
Published: August 2002

AbstractAn investigation is reported of the physical and chemical reactions at the wheel/workpiece interface during grinding of a nickel‐based superalloy K417. The temperature at the wheel/workpiece interface was measured using a workpiece–foil thermocouple and the forces were detected using a dynamometer. Scanning electron microscopy was used to examine deformations on ground workpiece surfaces and wear characteristic of abrasive grits. The chemical composition, of the ground surfaces, the depth chemical composition and the thickness of oxide layers were determined by XPS and its depth profile technique. A different burning colour was found on the ground workpiece surfaces when temperatures at the wheel/workpiece interface are >990 °C. Along with the emergence of a burning colour, adhesion occurs between the abrasive grits and the workpiece, causing plastically deformed coatings to appear and gradually spread on the ground workpiece surfaces. A physical model was proposed to account for the wear process of abrasive grits and the formation of plastically deformed coatings on the workpiece ground surfaces. Analysis by XPS reveals that chemical reactions take place on the workpiece surfaces due to the high temperatures generated in grinding, and transfer films composed of such oxides as Ni2O3, TiO2, Cr2O3 and A12O3 are formed on the workpiece surfaces. The colour generated on the ground workpiece surfaces depends on the thickness of the transfer films, which was found to be closely related to the interface temperature. Copyright © 2002 John Wiley & Sons, Ltd.
Coping with missing data in clinical trials: A model‐based approach applied to asthma trials
Authors: Carpenter James , Pocock Stuart , Johan Lamm Carl 
Published: August 2002

AbstractIn most clinical trials, some patients do not complete their intended follow‐up according to protocol, for a variety of reasons, and are often described as having ‘dropped out’ before the conclusion of the trial. Their subsequent measurements are missing, and this makes the analysis of the trial's repeated measures data more difficult. In this paper we briefly review the reasons for patient drop‐out, and their implications for some commonly used methods of analysis. We then propose a class of models for modelling both the response to treatment and the drop‐out process. Such models are readily fitted in a Bayesian framework using non‐informative priors with the software BUGS. The results from such models are then compared with the results of standard methods for dealing with missing data in clinical trials, such as last observation carried forward. We further propose the use of a time transformation to linearize an asymptotic pattern of repeated measures over time and therefore simplify the modelling. All these ideas are illustrated using data from a five‐arm asthma clinical trial. Copyright © 2002 John Wiley & Sons, Ltd.
Statistical methods for assessing the influence of study characteristics on treatment effects in ‘meta‐epidemiological’ research
Authors: Sterne Jonathan A. C. , Jüni Peter , Schulz Kenneth F. , Altman Douglas G. , Bartlett Christopher , Egger Matthias 
Published: August 2002

AbstractBiases in systematic reviews and meta‐analyses may be examined in ‘meta‐epidemiological’ studies, in which the influence of trial characteristics such as measures of study quality on treatment effect estimates is explored. Published studies to date have analysed data from collections of meta‐analyses with binary outcomes, using logistic regression models that assume that there is no between‐ or within‐meta‐analysis heterogeneity. Using data from a study of publication bias (39 meta‐analyses, 394 published and 88 unpublished trials) and language bias (29 meta‐analyses, 297 English language trials and 52 non‐English language trials), we compare results from logistic regression models, with and without robust standard errors to allow for clustering on meta‐analysis, with results using a ‘meta‐meta‐analytic’ approach that can allow for between‐ and within‐meta‐analysis heterogeneity. We also consider how to allow for the confounding effects of different trial characteristics. We show that both within‐ and between meta‐analysis heterogeneity may be of importance in the analysis of meta‐epidemiological studies, and that confounding exists between the effects of publication status and trial quality. Copyright © 2002 John Wiley & Sons, Ltd.
Simultaneous comparison of sensitivity and specificity of two tests in the paired design: a straightforward graphical approach
Authors: Newcombe Robert G. 
Published: August 2002

AbstractOften the performances of two binary diagnostic or screening tests are compared by applying them to the same set of subjects, some of whom are affected, some unaffected. The McNemar test, and corresponding interval estimation methods, may be used to compare the sensitivity of the two tests, but this disregards both any observed difference in specificity and its imprecision due to sampling variation. The suggested approach is to display point and interval estimates for a weighted mean ƒ of the differences in sensitivity and specificity between the two tests. The mixing parameter λ, which is allowed to range from 0 to 1, represents the prevalence in the population to which application is envisaged, together with the relative seriousness of false positives and false negatives. The confidence interval for ƒ is obtained by a simple extension of a closed‐form method for the paired difference of proportions, which has favourable coverage properties and is based on the Wilson single proportion score method. A plot of ƒ against λ is readily obtained using a Minitab macro. Copyright © 2001 John Wiley & Sons, Ltd.
Does group membership matter? Evidence from the Japanese steel industry
Authors: Nair Anil , Kotha Suresh 
Published: August 2002

AbstractIn this study we address criticism that performance differences among strategic groups found in past research may be spurious and attributable to firm effects. The Japanese steel industry provides the setting for the study. Our analysis is based on data from the carbon steel sector of the Japanese steel industry for the periods 1980–87 and 1988–93. A one‐way ANOVA indicated that the average performance of firms in the two technology‐based groups in this industry—the integrated mills and the minimills—were significantly different during the two periods. Subsequently, we performed a regression analysis to examine the residual group effect after controlling for both environment and firm‐specific effects. We found that even after controlling for both environment and firm‐specific effects group membership was significantly associated with firm performance. Copyright © 2001 John Wiley & Sons, Ltd.
Post‐formation dynamics in strategic alliances
Authors: Reuer Jeffrey J. , Zollo Maurizio , Singh Harbir 
Published: August 2002

AbstractThis paper investigates the occurrence and determinants of post‐formation governance changes in strategic alliances, including alterations in alliances' contracts, boards or oversight committees, and monitoring mechanisms. We examine alliances in the biotechnology industry and find that firms' unique alliance experience trajectories affect the likelihood of such ex post adjustments in these partnerships. Transactional features such as the alliance's scope, its division of labor, and the relevance of the collaboration to the parent firm also bear upon alliances' dynamics. We discuss the implications of these findings and how they complement prior research focusing on alliance design or termination at opposite ends of the alliance life cycle. Copyright © 2002 John Wiley & Sons, Ltd.
Incremental parsing in language‐based editors: user needs and how to meet them
Authors: Cook Phil , Welsh Jim 
Published: August 2002

AbstractIncremental parsing has long been recognized as a technique of great utility in the construction of language‐based editors, and correspondingly, the area currently enjoys a mature theory. Unfortunately, many practical considerations have been largely overlooked in previously published algorithms. Many user requirements for an editing system necessarily impact on the design of its incremental parser, but most approaches focus only on one: response time. This paper details an incremental parser based on LR parsing techniques and designed for use in a modeless syntax recognition editor. The nature of this editor places significant demands on the structure and quality of the document representation it uses, and hence, on the parser. The strategy presented here is novel in that both the parser and the representation it constructs are tolerant of the inevitable and frequent syntax errors that arise during editing. This is achieved by a method that differs from conventional error repair techniques, and that is more appropriate for use in an interactive context. Furthermore, the parser aims to minimize disturbance to this representation, not only to ensure other system components can operate incrementally, but also to avoid unfortunate consequences for certain user‐oriented services. The algorithm is augmented with a limited form of predictive tree‐building, and a technique is presented for the determination of valid symbols for menu‐based insertion. Copyright © 2001 John Wiley & Sons, Ltd.
Systems theory and the spirit of feminism: grounds for a connectiona
Authors: Hanson Barbara 
Published: August 2002

AbstractGeneral systems theory is compatible with the spirit of feminist thought. The unnecessary association of systems theory with hierarchy and status quo‐oriented proponents has formed a limited impression of what it can offer to feminisms. Looking at a fuller range of systems‐oriented work shows up that, like feminisms, systems theory has been radical in its rejection of traditional ways of analytic thinking. This paper looks at two central feminist ideas, sexuality and equality, as a spirit of feminism to forge a link between feminisms and systems theory. This shows up several areas of common ground between feminisms and a general systems theory approach to the benefit of both. The idea that action and inaction and equally causal derives from cybernetics and echoes a cell to action for social change in feminisms. Cybernetic causality reflects notions of discourse and fluid identities, allowing analysts to move beyond blame and dichotomous units. The idea that systems of logic are parallel relates closely to standpoint feminism. Systems focus on different outcomes to the same stimuli provides a way to capture emotion as a property of human interaction. Copyright © 2001 John Wiley & Sons, Ltd.
18F‐dopa PET evidence that tolcapone acts as a central COMT inhibitor in Parkinson's disease
Authors: Ceravolo Roberto , Piccini Paola , Bailey Dale L. , Jorga Karin M. , Bryson Helen , Brooks David J. 
Published: August 2002

AbstractTolcapone is a potent, selective, and reversible inhibitor of cathecol‐O‐methyl‐transferase (COMT). This enzyme plays a crucial role in the extraneural inactivation of catecholamine neurotransmitters. Tolcapone's ability to inhibit central COMT in humans at therapeutic concentrations is not yet clear. The aim was to determine the effect of tolcapone on central COMT activity in Parkinson's disease (PD) using 18F‐dopa positron emission tomography (PET). The study was a randomized two‐way crossover study. Twelve PD patients were recruited. On the treatment days patients were given either tolcapone (200 mg) or placebo together with levodopa/carbidopa (100/125 mg) 1 h before the injection of 18F‐dopa. Data were acquired in 25 frames over 94 min for the first PET scan period. At the end of this period the patients were removed from the scanner for 90 min and subsequently repositioned and data acquired in six 10‐min time frames over 60 min. Influx constants (Ki) were computed using a graphical approach with a plasma input function. Mean 18F‐dopa putamen Ki's for the first 30–90 min, primarily reflecting central dopa decarboxylase (DDC) activity, were similar in PD patients whether tolcapone was present (0.0078 ± 0.0031 min−1) or absent (0.0078 ± 0.0030 min−1). Mean putamen Ki values calculated 180–240 min after injection of 18F‐dopa, reflecting both central DDC and COMT activity, were unchanged from 30–90′ values in the presence of tolcapone (0.0079 ± 0.0030), implying blockade of central COMT, but were significantly reduced (0.0059 ± 0.0028) in the absence of this drug. These findings are compatible with clinical doses of tolcapone having a significant blocking effect on peripheral and central COMT but not DDC activity in PD. Synapse 43:201–207, 2002. © 2002 Wiley‐Liss, Inc.
D2 but not D3 receptors are elevated after 9 or 11 months chronic haloperidol treatment: Influence of withdrawal period
Authors: Joyce Jeffrey N. 
Published: August 2002

AbstractPrevious postmortem studies have identified divergent alterations in D2 and D3 receptors in schizophrenia but those results cannot be interpreted without further understanding of whether antipsychotic regulation of the D3 receptor is different from that of the D2 receptor. Depot parenteral administration of haloperidol decanoate was utilized to achieve consistent high levels in rat brain for 9 months with 2‐month withdrawal or 11 months with 48‐h withdrawal and compared to vehicle control and acute haloperidol (48‐h) treatment groups. Autoradiographic means for measuring levels of D2 ([3H]‐spiperone) and D3 receptors ([125I]trans 7‐OH‐PIPAT) and of D3 mRNA by in situ hybridization histochemistry in rat caudate‐putamen, nucleus accumbens, islands of Calleja, and olfactory tubercle determined that there were significant group differences for regulation of D2 receptor. Chronic haloperidol for 9 or 11 months elevated D2 but not D3 receptors or D3 mRNA in all regions measured. Acute haloperidol treatment had no significant effects for any measure. Treatment for 9 months with a 2‐month withdrawal resulted in a persistent increase in D2 receptors that was greater than that observed in the 11 months with 48‐h withdrawal. This effect was most noticeable in the olfactory tubercle. These data confirm previous findings that short‐ or long‐term haloperidol treatment leads to elevations in D2 but not D3 receptors or D3 mRNA, and long‐term withdrawal from chronic haloperidol does not lead to elevations in D3 receptors or D3 mRNA. This suggests that an elevation in D3 receptors identified at postmortem in schizophrenics withdrawn from antipsychotics is not the result of the previous drug history [Gurevich et al. (1997) Arch Gen Psychiatry 54:225–232]. Synapse 40:137–144, 2001. © 2001 Wiley‐Liss, Inc.
Evolution of pharmaceutical regulations and their consequences in the European Union and the United States
Authors: Tancer Robert S. , Mosseri‐Marlio C. 
Published: August 2002

AbstractThis article examines the nature of the European Union (EU) and United States regulation of the
pharmaceutical industry in recent years. A series of Regulations and Directives issued by the European Commission
and reinforced by decisions of the European Court of Justice have achieved harmonization of the pharmaceutical
industry throughout the EU. In the U.S., as a result of the federal system, harmonization has not been a issue;
the focus of regulation has been to achieve a balance between those companies using research and development
(R&D) to create innovative products and the generic companies which provide quality medicines at lower
costs to the consumer. Notwithstanding this difference in orientation, similar problems have been faced in the EU
and the U.S.: patent term extension, pediatric versions, and assurance that new drugs are safe and effective. The
similarity of issues and often their solutions should not be surprising since the pharmaceutical industry is truly
global. U.S. products are sold throughout the EU and European products are readily available in the U.S. The level
of regulation, both in the EU and the U.S. has not stymied the industry, as it remains a global leader in developing
new and innovative products utilized throughout the world. © 2002 Wiley Periodicals, Inc.
Dealing with financial crises in emerging markets
Authors: Mudd Shannon , Grosse Robert , Mathis John 
Published: August 2002

AbstractFinancial crises in emerging markets are a reality of doing business in these countries in the early
twenty‐first century. Managers can gain some perspective on this problem from experiences of firms in
crises that occurred in Mexico, Thailand, and Russia during the 1990s. We show how firms have taken steps to
protect themselves against financial crises and to deal with the crises once underway in these three countries.
Such strategies are divided into frameworks of: short‐term, immediate responses to a crisis;
intermediate steps during the period of economic downturn; and long‐term continuing responses for
operating in emerging markets. © 2002 Wiley Periodicals, Inc.
The value‐relevance of financial and non‐financial information for Internet companies
Authors: Graham Carol M. , Cannice Mark V. , Sayre Todd L. 
Published: August 2002

AbstractThis article assesses the extent to which non‐financial measures of Internet usage are incrementally
value‐relevant over and above basic financial information across four Internet industry sectors. Using
ordinary least squares (OLS) regression analysis we test the extent to which net income, book value,
unique users, page views, and hours per user are able to explain stock prices for a sample of 341 firm quarters
for the period Q1: 1999–Q1: 2000. Our results indicate that net income has no ability to explain market
values for the pooled sample or for any of the Internet sectors examined. With respect to the non‐financial
variables, we find that for e‐tailers and content/community firms, page views have the greatest
explanatory power. For service companies, unique users have the greatest ability to explain market values, and for
infrastructure companies, none of our non‐financial variables are significant. © 2002 John Wiley &
Sons, Inc.
Rapid Internet development in China: A discussion of opportunities and constraints on future growth
Authors: Zhao HongXin 
Published: August 2002

AbstractChina has exhibited fast Internet growth. The number of Internet users in China doubled every six months in
the last two years. What accounts for such a rapid adoption of the Internet in China? What are the
constraints and opportunities? This article describes the facilitating roles played by the large pool of
Information Technology (IT) personnel, fast diffusion of personal computers, telecom infrastructure,
and digital networks, and the active foreign involvements. At the same time, the article identifies a number of
factors such as slow speed, high costs, murky regulations, imbalanced development, and absence of credit
systems, limiting the current growth. © 2002 John Wiley & Sons, Inc.
Numerical simulation of wind tunnel wall effects on wind turbine flows
Authors: Wang Tongguang , Coton Frank N. 
Published: August 2002

AbstractA low‐order panel method and a prescribed wake vortex model have been combined into a coupled model capable of assessing the basic effect of wind tunnel walls on wind turbine flow and performance. The wind tunnel walls are discretised into a series of panels, and sources distributed on these panels simulate the constraint effect of the wind tunnel walls. The wind turbine and its wake are represented by the prescribed wake model. The source strengths are related to the induced velocities at the panel control points due to the turbine vortex system by satisfying the boundary condition of zero normal velocity on the solid tunnel wall. The vortex‐induced and source‐induced velocities at the blade are summed to determine an interim turbine wake using the prescription functions. The effects of the disturbance velocities due to the source panels are then superposed upon the prescribed wake to obtain the final wake geometry under the influence of wind tunnel wall interference. The model developed in this study is compared with wind turbine wake measurements made in a low‐speed wind tunnel. Generally, the model is found to compare well with experiment, although some discrepancies are noted. Finally, possible future improvements to the combined method are recommended. Copyright © 2001 John Wiley & Sons, Ltd.
Direct comparison of total reflection techniques by using a plate beamguide
Authors: Sánchez Héctor J. 
Published: August 2002

AbstractThis paper reports an experimental characterization of different techniques for total reflection x‐ray fluorescence analysis, namely grazing incidence and grazing emission methods. A direct comparison was performed by using a new collimating system based on a plate beamguide device. This device allows the transport of photons along the sample–detector path or the source–detector path in the total reflection regime, and a simple and easy way to set up the two methods of measurement. Spectra from total reflection experiments in grazing incidence and grazing emission conditions were obtained using a conventional x‐ray source. Detection limit calculations of different standard samples were carried out for the two techniques. These values were also compared with those obtained by means of conventional x‐ray fluorescence analysis for the same samples and the same irradiation system. The different factors involved in the determination of detection limits for each method are analyzed and a possible explanation of the results obtained is given. Copyright © 2002 John Wiley & Sons, Ltd.