bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cross‐resistance potential of fipronil in Musca domestica
Authors: Kristensen Michael , Jespersen Jørgen B , Knorr Mette 
Published: March 2004

AbstractThe toxicity of fipronil to insecticide‐susceptible houseflies and the cross‐resistance potential of fipronil were determined for six insecticide‐resistant laboratory housefly strains by topical application and feeding bioassay. The insecticide‐resistant strains represented different levels and patterns of resistance to pyrethroids, organophosphates, carbamates and organochlorines. Five strains were almost susceptible to fipronil in feeding bioassay with resistance factors at LC50 between 0.36 and 3.0. Four of these strains were almost susceptible to topically applied fipronil (resistance factors at LD50 were 0.55, 0.83, 3.3 and 2.5, respectively), whereas one strain was 13‐fold resistant to topically applied fipronil. A highly γ‐HCH‐resistant strain, 17e, was 430‐fold resistant to fipronil in topical application bioassay and 23‐fold resistant in feeding bioassay at LD50/LC50. We also tested the toxicity of fipronil in a feeding bioassay and γ‐HCH in topical application bioassay on thirteen housefly field populations. Eleven of the field populations had resistance factors for fipronil ranging from 0.98 to 2.4 at LC50, whereas two populations were 4.0‐ and 4.6‐fold resistant to fipronil. The resistance level to γ‐HCH at LD50 in the field populations ranged from 1.8‐ to 8.1‐fold. The two strains showing fipronil resistance were 3.4‐ and 8.1‐fold resistant to γ‐HCH. Fipronil and γ‐HCH toxicities were positively correlated in the field populations. Biochemical assays of esterase, glutathione S‐transferase and cytochrome P450 monooxygenase indicated that the low fipronil resistance observed in laboratory and field strains could be caused by elevated detoxification or be due to a target‐site resistance mechanism with cross‐resistance to γ‐HCH. Copyright © 2004 Society of Chemical Industry
A second threshold for the hard‐core model on a Bethe lattice
Authors: Brightwell Graham R. , Winkler Peter 
Published: March 2004

AbstractWe determine the approximate value of a critical activity for the hard‐core model on the Bethe lattice, which determines whether the unique simple invariant Gibbs measure is extremal. This “recovery threshold” turns out to be different both from the threshold for unique Gibbs measure and (in contrast to the Ising model) from the threshold for recovery of root information using only statistical information about distant sites. © 2004 Wiley Periodicals, Inc. Random Struct. Alg., 2004
A regression shrinkage method tailored to qualitative regressors and clustered data
Authors: Neumann Anke , Holstein Josiane , Chatellier Gilles , Lepage Eric 
Published: March 2004

AbstractWe propose a shrinkage method for estimation in linear regression models with qualitative regressors. Due to the nature of the shrinkage constraint, this method tends to give estimates that are exactly zero for some groups of coefficients belonging to the same regressor. The method hence results in concise models, since some of the regressors are entirely eliminated. In conjunction with this estimation method, a model with a fixed cluster effect turns out to be closely related to frailty models. We apply the method for modelling hospital readmissions. Copyright © 2004 John Wiley & Sons, Ltd.
A breast cancer prediction model incorporating familial and personal risk factors
Authors: Tyrer Jonathan , Duffy Stephen W. , Cuzick Jack 
Published: March 2004

AbstractAn Erratum has been published for this article in Statistics in Medicine 2005; 24(1):156.Please note that the corresponding author's e‐mail address has now changed. For further details please click on the link below.DOI: 10.1002/sim.1913.Many factors determine a woman's risk of breast cancer. Some of them are genetic and relate to family history, others are based on personal factors such as reproductive history and medical history. While many papers have concentrated on subsets of these risk factors, no papers have incorporated personal risk factors with a detailed genetic analysis. There is a need to combine these factors to provide a better overall determinant of risk. The discovery of the BRCA1 and BRCA2 genes has explained some of the genetic determinants of breast cancer risk, but these genes alone do not explain all of the familial aggregation of breast cancer. We have developed a model incorporating the BRCA genes, a low penetrance gene and personal risk factors. For an individual woman her family history is used in conjuction with Bayes theorem to iteratively produce the likelihood of her carrying any genes predisposing to breast cancer, which in turn affects her likelihood of developing breast cancer. This risk was further refined based on the woman's personal history. The model has been incorporated into a computer program that gives a personalised risk estimate. Copyright © 2004 John Wiley & Sons, Ltd.
Robust Bayesian decision theory applied to optimal dosage
Authors: Abraham Christophe , Daurès Jean‐Pierre 
Published: March 2004

AbstractWe give a model for constructing an utility function u(θ,d) in a dose prescription problem. θ and d denote respectively the patient state of health and the dose. The construction of u is based on the conditional probabilities of several variables. These probabilities are described by logistic models. Obviously, u is only an approximation of the true utility function and that is why we investigate the sensitivity of the final decision with respect to the utility function. We construct a class of utility functions from u and approximate the set of all Bayes actions associated to that class. Then, we measure the sensitivity as the greatest difference between the expected utilities of two Bayes actions. Finally, we apply these results to weighing up a chemotherapy treatment of lung cancer. This application emphasizes the importance of measuring robustness through the utility of decisions rather than the decisions themselves. Copyright© 2004 John Wiley & Sons, Ltd.
A non‐parametric procedure for evaluating treatment effect in the meta‐analysis of survival data
Authors: Moodie Patricia F. , Nelson Norma A. , Koch Gary G. 
Published: March 2004

AbstractThis paper addresses the problem of combining information from independent clinical trials which compare survival distributions of two treatment groups. Current meta‐analytic methods which take censoring into account are often not feasible for meta‐analyses which synthesize summarized results in published (or unpublished) references, as these methods require information usually not reported. The paper presents methodology which uses the log(‐log) survival function difference, (i.e. log(‐logS2(t))‐log(‐logS1(t)), as the contrast index to represent the multiplicative treatment effect on survival in independent trials. This article shows by the second mean value theorem for integrals that this contrast index, denoted as θ, is interpretable as a weighted average on a natural logarithmic scale of hazard ratios within the interval [0,t] in a trial. When the within‐trial proportional hazards assumption is true, θ is the logarithm of the proportionality constant for the common hazard ratio for the interval considered within the trial. In this situation, an important advantage of using θ as a contrast index in the proposed methodology is that the estimation of θ is not affected by length of follow‐up time. Other commonly used indices such as the odds ratio, risk ratio and risk differences do not have this invariance property under the proportional hazard model, since their estimation may be affected by length of follow‐up time as a technical artefact. Thus, the proposed methodology obviates problems which often occur in survival meta‐analysis because trials do not report survival at the same length of follow‐up time. Even when the within‐trial proportional hazards assumption is not realistic, the proposed methodology has the capability of testing a global null hypothesis of no multiplicative treatment effect on the survival distributions of two groups for all studies. A discussion of weighting schemes for meta‐analysis is provided, in particular, a weighting scheme based on effective sample sizes is suggested for the meta‐analysis of time‐to‐event data which involves censoring. A medical example illustrating the methodology is given. A simulation investigation suggested that the methodology performs well in the presence of moderate censoring. Copyright © 2004 John Wiley & Sons, Ltd.
Sensitivity analysis of longitudinal normal data with drop‐outs
Authors: Minini Pascal , Chavance Michel 
Published: March 2004

AbstractWe propose to perform a sensitivity analysis to evaluate the extent to which results from a longitudinal study can be affected by informative drop‐outs. The method is based on a selection model, where the parameter relating the dropout probability to the current observation is not estimated, but fixed to a set of values. This allows to evaluate several hypotheses for the degree of informativeness of the drop‐out process. Expectation and variance of missing data, conditional on the drop‐out time are computed, and a stochastic EM algorithm is used to obtain maximum likelihood estimates. Simulations show that when the drop‐out parameter is correctly specified, unbiased estimates of the other parameters are obtained, and coverage percentages of their confidence intervals are close to their theoretical value. More interestingly, misspecification of the drop‐out parameter does not considerably alter these results. This method was applied to a randomized clinical trial, designed to demonstrate non‐inferiority of an inhaled corticosteroid in terms of bone density, compared with a reference treatment. Sensitivity analysis showed that the conclusion of non‐inferiority was robust against different hypotheses for the drop‐out process. Copyright © 2004 John Wiley & Sons, Ltd.
Outside directors and firm performance during institutional transitions
Authors: Peng Mike W. 
Published: March 2004

AbstractDo outside directors on corporate boards make a difference in firm performance during institutional transitions? What leads to the practice of appointing outside directors in the absence of legal mandate? This article addresses these two important questions by drawing not only on agency theory, but also resource dependence and institutional theories. Taking advantage of China's institutional transitions, our findings, based on an archival database covering 405 publicly listed firms and 1211 company–years, suggest that outsider directors do make a difference in firm performance, if such performance is measured by sales growth, and that they have little impact on financial performance such as return on equity (ROE). The results also document a bandwagon effect behind the diffusion of the practice of appointing outsiders to corporate boards. The article not only highlights the need to incorporate multiple theories beyond agency theory in corporate governance research, but also generates policy implications in light of the recent trend toward having more outside directors on corporate boards in emerging economies. Copyright © 2004 John Wiley & Sons, Ltd.
Within‐business diversification in technology‐intensive industries
Authors: Stern Ithai , Henderson Andrew D. 
Published: March 2004

AbstractThis study extends diversification research to a new level of analysis, examining how within‐business diversification, which occurs when firms extend existing product lines or expand into new ones, affects organizational survival. While prior research suggests that corporate‐level diversification accounts for relatively little variation in performance, within‐business diversification matters a great deal, by influencing which start‐ups survive and which firms better cope with rapid environmental change. Specifically, we find that the relationship between within‐business diversity and survival is contingent on the amount of environmental change wrought by a firm's competitors as they simultaneously diversify their own product portfolios and innovate technologically. Analysis of the population of U.S. personal computer manufacturers from the industry's founding in 1975 through 1994 supports our premise: Regardless of its effects across businesses, diversification matters a great deal within them. Copyright © 2004 John Wiley & Sons, Ltd.
Influence of Conditions of Maize Starch Enzymatic Hydrolysis on Physicochemical Properties of Glucose Syrups
Authors: Nebesny Ewa , Rosicka Justyna , Tkaczyk Mariola 
Published: March 2004

AbstractAmylose complexed with lipid is more resistant to the attack of amylolytic enzymes than the free polysaccharide. The susceptibility of amylose‐lipid complexes (AML) present in maize starch to enzymatic digestion still remains obscure, although the enzymatic hydrolysis of AML with defined composition, prepared from amylose and selected lipids, was an objective of several research projects. Therefore our studies were aimed at elucidation of AML properties and their relationship with features of maize starch hydrolysates, particularly with respect to the character of a lipolytic enzyme, additionally used for saccharification, apart from the glucoamylase. Differential scanning calorimetry (DSC) measurements revealed that treatment of maize starch with suitable α‐amylase preparation resulted in significant degradation of AML. More pronounced cleavage of AML can be also achieved by using both amylolytic and lipolytic enzymes for starch saccharification. The lysophospholipase appeared to be particularly active towards AML when used with glucoamylase. The common application of these enzymes brought about an enhanced glucose yield and filtration rate, and better color and transparency of the final product.
Exploratory Studies on the Carboxymethylation of Cassava Starch in Water‐miscible Organic Media
Authors: Jie Yao , Wen‐ren Chen , Manurung Robbert M. , Ganzeveld Klaassien J. , Heeres Hero J. 
Published: March 2004

AbstractThe carboxymethylation of cassava starch using sodium monochloroacetate (SMCA) as an etherification agent was investigated. Mixtures of water and water‐miscible organic liquids were selected as carboxymethylation reaction medium to obtain a high degree of substitution (DS) without changing the granular form and to prevent gelatinization. Factors that affect the process of chemical modification of cassava starch, including the type of solvents, the mass percentage of water in the reaction medium, the mass percentage of starch, the molar ratio of NaOH to SMCA, the theoretical DS (DSt), and the temperature were investigated experimentally. Isopropanol and tert‐butanol appear to be the best solvents for the carboxymethylation process of cassava starch, and the optimum condition for this etherification reaction are a reaction medium consisting of about 10 wt% water, a reaction temperature between 50 and 55°C and a starch mass percentage between 4–8 wt%. When applying these conditions in combination with a DSt of 2.5, granular modified cassava starch with a DS of 1.4 can be obtained. The experimental results will be compared with those reported for other types of granular starches.
The Role of Hydrogen Bonding in Amylose Gelation
Authors: McGrane Scott J. , Mainwaring David E. , Cornell Hugh J. , Rix Colin J. 
Published: March 2004

AbstractStudies of the rheological properties of amylose gels in mixtures of water and DMSO have shown that these properties are dependent upon the formation of intramolecular and intermolecular hydrogen bonds. In DMSO, it is proposed that amylose has a tight helical conformation which is maintained by intramolecular hydrogen bonding. When water is added it is proposed that intramolecular hydrogen bonds are replaced with intermolecular hydrogen bonds and thus the rheological properties are changed due to the more extended and flexible amylose molecules adopting an interrupted helical conformation.Because of these changes in conformation, increased water content results in strong elastic gels, commensurate with it being the dominant gel‐forming component in starch, due to its ability to form networks with water through intermolecular hydrogen bonding. The addition of various polyols to solutions of amylose in DMSO also resulted in strong elastic gels being formed. It is proposed that polyols such as 1,3‐propanediol are also able to form networks in a similar way to water.The use of intermolecular hydrogen bond breaking agents, such as urea, reduced gel strength significantly, but the intra‐molecular bond‐breaking agent, 1,1,3,3‐tetramethyl urea (TMU), was not so effective. The results of this work are further evidence of intermolecular hydrogen bonding networks between amylose and water as being of fundamental importance in the strength of starch gels.
Biosynthetic studies of the DSP toxin skeleton
Authors: Daranas Antonio H. , Fernández José J. , Norte Manuel , Gavín José A. , Suárez‐Gómez Blanca , Souto María L. 
Published: March 2004

AbstractMarine toxins have drawn wide interest because their economical impact and disastrous effect upon the
shellfish industry and public health in many parts of the world. One of the most interesting group of substances of
marine toxins, from structural and pharmacological points of view are polyether compounds, which generally present a
great diversity in size and potent biological activities. The subject of this work was about to biosynthesis of okadaic
acid skeleton as leader as DSP toxins. Its biosynthesis attracts considerable attention since the carbon skeleton has
been shown to be synthesised via an unusual route. In this paper we report on stable isotope incorporation experiments
on DSP toxin in artificial cultures of dinoflagellate. The comparison of the degrees of incorporation in these samples
measured by different methods led to contradictory results. This implies that further experimental data is needed in
order to propose a logical biogenetic scheme. © 2004 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.
Chem Rec 4: 1–9; 2004: Published online in Wiley InterScience
(www.interscience.wiley.com
) DOI 10.1002/tcr.10072
Towards the biaxial nematic phase through molecular design
Authors: Bruce Duncan W. 
Published: March 2004

AbstractIn this article, the search for the elusive biaxial nematic phase (NB) in liquid crystals
is considered. The structure of the phase is described along with theoretical and computational work which suggests
how it might be realised. An overview of the work of the Exeter group in this area is then given showing the different
approaches adopted and illustrating how one of these has led to a new type of amphiphilicity based on shape. © 2004
The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 4: 10–22; 2004: Published online in Wiley
InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.10073
Femtosecond laser‐induced microstructures in glasses and applications in micro‐optics
Authors: QIU JIANRONG 
Published: March 2004

AbstractFemtosecond laser has been widely used in microscopic modifications to materials due to its ultra‐short laser pulse
and ultrahigh light intensity. When a transparent material e.g. glass is irradiated by a tightly focused femtosecond laser, the photo‐induced
reaction is expected to occur only near the focused part of the laser beam inside the glass due to the multiphoton processes. We observed
various induced structures e.g. color center defects, refractive index change, micro‐void and micro‐crack, in glasses after
the femtosecond laser irradiation. In this paper, we review the femtosecond laser induced phenomena and discuss the mechanisms of the observed
phenomena. We also introduce the fabrication of various micro‐optical components, e.g. optical waveguide, micro‐grating,
micro‐lens, fiber attenuator, 3‐dimensional optical memory by using the femtosecond laser‐induced structures. The
femtosecond laser will open new possibilities in the fabrication of micro‐optical components with various optical functions.
© 2004 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 4: 50–58; 2004: Published online in Wiley
InterScience (www.interscience.wiley.com
) DOI 10.1002/tcr.20006
Prospective evaluation of blood flow in the myometrium and uterine arteries in the puerperium
Authors: Van Schoubroeck D. , Van Den Bosch T. , Scharpe K. , Lu C. , Van Huffel S. , Timmerman D. 
Published: March 2004

AbstractObjectiveHeavy bleeding in the late postpartum has, in some cases, been attributed to subinvolution of the placental bed and enhanced myometrial vascularity (EMV) as seen on color Doppler imaging. The aim of this study was to investigate the incidence and spontaneous evolution of areas of enhanced vascularization over the whole thickness of the myometrium in asymptomatic women after uncomplicated term pregnancy.MethodsThis was a prospective descriptive study involving 93 consecutive women who were examined on day 3 (mean 2.6 ± 1.5) and at 6 weeks (mean 6.5 ± 1.3) after delivery following an uncomplicated term pregnancy. EMV was defined as the presence of marked flow over the full thickness of the myometrium reaching the uterine cavity. Doppler flow examination within the area of EMV and of both uterine arteries was performed.ResultsThe mean patient age was 29.1 years and average parity was 1.7. The mean gestational age at delivery was 39.1 weeks. Areas of EMV were visualized in 50.5% of patients on day 3 vs. 3.9% at 6 weeks. None of the patients required therapy for bleeding problems. The mean pulsatility index and peak systolic velocity in the area of EMV on day 3 were 0.45 ± 0.30 and 0.37 ± 0.20 m/s, respectively. A consistent increase in vascular resistance and decrease in blood flow velocity was observed in both uterine arteries between day 3 and week 6.ConclusionsMost areas of EMV reflect intermediate stages in the involution of the placental bed and do not cause abnormal postpartum bleeding. EVM is common in the puerperium, disappears spontaneously in the vast majority of cases, and does not warrant treatment if asymptomatic. Further research is needed to predict the rare cases in which subinvolution of the placental bed leads to heavy bleeding in the late postpartum. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Disciplined, efficient, generalised folds for nested datatypes
Authors: Martin Clare , Gibbons Jeremy , Bayley Ian 
Published: March 2004

Abstract.

Nested (or non-uniform, or non-regular) datatypes have recursive definitions in which the type parameter changes. Their folds are restricted in power due to type constraints. Bird and Paterson introduced
generalised folds
for extra power, but at the cost of a loss of efficiency: folds may take more than linear time to evaluate. Hinze introduced
efficient generalised folds
to counter this inefficiency, but did so in a pragmatic way: he did not provide categorical or equivalent underpinnings, so did not get the associated universal properties for manipulating folds. We combine the efficiency of Hinze’s construction with the powerful reasoning tools of Bird and Paterson’s.