bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of follow‐up experiments for improving model discrimination and parameter estimation
Authors: Ng Szu Hui , Chick Stephen E. 
Published: September 2004

AbstractOne goal of experimentation is to identify which design parameters most significantly influence the mean performance of a system. Another goal is to obtain good parameter estimates for a response model that quantifies how the mean performance depends on influential parameters. Most experimental design techniques focus on one goal at a time. This paper proposes a new entropy‐based design criterion for follow‐up experiments that jointly identifies the important parameters and reduces the variance of parameter estimates. We simplify computations for the normal linear model by identifying an approximation that leads to a closed form solution. The criterion is applied to an example from the experimental design literature, to a known model and to a critical care facility simulation experiment. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004
On optimization of bio‐probes
Authors: Pedersen N. L. 
Published: September 2004

AbstractThe present paper deals with the modelling and optimization of small bio‐probes that can be used for biological sensing; the bio‐probes can be classified as MicroElectroMechnical Systems (MEMS). The objective is to optimize the structure of the bio‐probes in order to maximize the sensing sensitivity. A biological coating results in a prestress on the sensing cantilever when certain molecules are present in the surrounding medium. The mechanical deformation due to the biological material is modelled by applying a prestress in the top layer of the bio‐probes. Topology optimization is used to improve the design. In the present work it is necessary to use an interpolation scheme different from the SIMP (power law) approach which is usually used in topology optimization. In calculating the sensitivities, needed for the optimization, complications due to the prestress occur, but also due to the coupling between the elastic field and the electric field which both must be used in an integrated model. These complications are dealt with and analytically obtained sensitivities are presented. Copyright © 2004 John Wiley & Sons, Ltd.
On the stable finite element procedures for dynamic problems of saturated porous media
Authors: Huang Maosong , Yue Zhong Qi , Tham L. G. , Zienkiewicz O. C. 
Published: September 2004

AbstractThe solution of problems in which coupling occurs between the displacement of the soil skeleton and the pore fluid pressure is fundamental in soil dynamics. The formulation requires that the interpolation functions for the displacement and pressure in the finite element discretization must satisfy the so‐called Babuska–Brezzi stability criteria or the patch test in the limit of nearly incompressible pore fluid and small permeability. The criteria are not fulfiled by elements with the same order of interpolation for both variables unless stabilization techniques are introduced. This paper summarizes the stabilization techniques that have been proposed in the literature to overcome volumetric locking for the incompressible or nearly incompressible soil dynamic behaviours. In particular, the staggered implicit–implicit algorithm (i.e. the fractional step method in an implicit form) and the direct α‐method proposed by the first author and Zienkiewicz et al. are briefly reviewed. Attentions will be paid to the steady‐state formulations resulted from both approaches. Based on the steady state formulations, the paper will then discuss the determination of the local stabilization parameters, with which a significant improvement for the obtained solutions of pore‐pressure can be achieved. Further discussion on the limitations of the methods is also given. Finally, several numerical examples are presented to illustrate the effectiveness of the proposed techniques. Copyright © 2004 John Wiley & Sons, Ltd.
A super‐element for crack analysis in the time domain
Authors: Song Chongmin 
Published: September 2004

AbstractA super‐element for the dynamic analysis of two‐dimensional crack problems is developed based on the scaled boundary finite‐element method. The boundary of the super‐element containing a crack tip is discretized with line elements. The governing partial differential equations formulated in the scaled boundary co‐ordinates are transformed to ordinary differential equations in the frequency domain by applying the Galerkin's weighted residual technique. The displacements in the radial direction from the crack tip to a point on the boundary are solved analytically without any a priori assumption. The scaled boundary finite‐element formulation leads to symmetric static stiffness and mass matrices. The super‐element can be coupled seamlessly with standard finite elements. The transient response is evaluated directly in the time domain using a standard time‐integration scheme. The stress field, including the singularity around the crack tip, is expressed semi‐analytically. The stress intensity factors are evaluated without directly addressing singular functions, as the limit in their definitions is performed analytically. Copyright © 2004 John Wiley & Sons, Ltd.
Constrained boundary recovery for three dimensional Delaunay triangulations
Authors: Du Qiang , Wang Desheng 
Published: September 2004

AbstractA new constrained boundary recovery method for three dimensional Delaunay triangulations is presented. It successfully resolves the difficulties related to the minimal addition of Steiner points and their good placement. Applications to full mesh generation are discussed and numerical examples are provided to illustrate the effectiveness of guaranteed recovery procedure. Copyright © 2004 John Wiley & Sons, Ltd.
On using linear elements in incompressible plane strain problems: a simple edge based approach for triangles
Authors: Boroomand B. , Khalilian B. 
Published: September 2004

AbstractIn this paper a simple iterative method is presented for finite element solution of incompressible plane strain problems using linear elements. Instead of using a mixed formulation approach, we use an equivalent displacement/velocity approach in an iterative manner. Control volumes are taken for regions which are to exhibit incompressible behaviour. For triangular elements the control volume is chosen as the area built on the parts of each pair of elements at the sides of an edge. In this case, elements are let to exchange volume. It is shown that the proposed edge based approach removes the deficiency of the linear triangular elements i.e. locking effect.Similar edge based approach is applied to the linear quadrilateral elements. However, if the control volume is chosen as the element volume the formulation gives similar results as the discontinuous mixed formulation using one pressure point without exhibiting instability behaviour. The formulation is based on decomposition of the displacement/velocity field into deviatoric and volumetric parts. The volumetric part is iteratively eliminated without confronting locking or instability phenomenon. The iterative procedure is very cheap and simple to be implemented in any FEM code. Several examples are given to demonstrate the performance of the procedure. Copyright © 2004 John Wiley & Sons, Ltd.
Regulatory impact assessment and regulatory governance in developing countries
Authors: Kirkpatrick Colin , Parker David 
Published: September 2004

AbstractRegulatory impact assessment (RIA) offers the means to improve regulatory decision‐making and practice. RIA involves a systematic appraisal of the costs and benefits associated with a proposed new regulation and evaluation of the performance of existing regulations. So far, the adoption of RIA has been confined mainly to OECD countries. The purpose of this article is to assess the contribution that RIA can make to ‘better regulation’ in developing countries. Results from a survey of a small number of middle‐income countries suggest that a number of developing countries apply some form of regulatory assessment, but that the methods adopted are partial in their application and are certainly not systematically applied across government. The article discusses the capacity building requirements for the adoption of RIA in developing countries, in terms of regulatory assessment skills, including data collection methods and public consultation practices. The article also proposes a framework for RIA that can be applied in low and middle‐income countries to improve regulatory decision‐making and outcomes. Copyright © 2004 John Wiley & Sons, Ltd.
Privatisation and liberalisation in the utility sector: the case of telecommunications in the Czech and Slovak Republics
Authors: Nemec Juraj , Sagat Vladimir , Vitek Leos 
Published: September 2004

AbstractThis article addresses the issue of telecommunications reform in the context of economic, political and technological changes. It reviews recent approaches to utilities and telecommunications management from the perspective of socio‐economic theories and with reference to European Union (EU) telecommunications policies. It then addresses telecommunications reform in the Czech and Slovak Republics as they prepare to join the EU. The emphasis is on the efficiency, pricing, quality and scope of services, as well as the social consequences of liberalisation. The indications are that, while liberalisation is favoured, certain basic government guarantees are still required in the ‘public interest’. Copyright © 2004 John Wiley & Sons, Ltd.
CDX1 expression is reduced in colorectal carcinoma and is associated with promoter hypermethylation
Authors: Pilozzi Emanuela , Onelli Mariadele Rapazzotti , Ziparo Vincenzo , Mercantini Paolo , Ruco Luigi 
Published: September 2004

AbstractThe CDX1 homeobox gene encodes a transcription factor specifically expressed in normal intestinal and colonic epithelia, and CDX1 gene expression is affected during colorectal tumour progression. In this study, real‐time quantitative RT‐PCR was used to investigate CDX1 expression in 26 colorectal carcinomas. Reduced expression of CDX1 was observed in 19 of 26 colon carcinomas compared to matched normal colonic mucosa: the decrease in CDX1 expression ranged between 0.10 and 0.79 (21–90% decrease; mean 64.75% ±22; p = 0.001). Mutation and loss of heterozygosity (LOH) analyses were then used to determine if reduced CDX1 expression was due to genetic alteration. No CDX1 gene mutations, but two known polymorphisms in exon 1, were observed. LOH was observed in 33% of the tumours investigated but this was not related to CDX1 expression. Since aberrant promoter methylation is a well‐known mechanism that participates in gene silencing, the methylation status of the CDX1 5′ CpG island promoter was also investigated. PCR amplification of bisulphite‐treated DNA followed by cloning was performed in 7 carcinomas that showed low expression of CDX1 and in 1 colonic carcinoma without reduced expression. Promoter hypermethylation occurred in carcinomas in which CDX1 reduced expression was present. These results suggest that CDX1 promoter hypermethylation is one of the molecular mechanisms that accounts for reduced CDX1 gene expression in colorectal carcinoma. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Modulation of dynamic release of vitamin B2 from a model pH‐sensitive terpolymeric hydrogel system
Authors: Bajpai SK , Dubey Seema 
Published: September 2004

AbstractTerpolymeric devices consisting of acrylamide, methacrylamide and acrylic acid were synthesized and the release of the model drug riboflavin from these devices was studied at the physiological temperature 37°C. The gels exhibit a sharp pH‐dependent release behavior. The devices released nearly 42.2 ± 2.6% drug at pH 1.0 while nearly 95.3 ± 3.2% drug was released at pH 7.4. With increasing concentration of cross‐linker in the gel, the drug released was found to decrease. Moreover, with low content of cross‐linker a nearly zero‐order profile was obtained. The size of the cylindrical devices also affected the release kinetics and a linear dependency was observed between t1/2 (ie, the time required for 50 % release) and the square of the diameter, thus supporting the Tanaka–Fillmore theory. The molar ratio of acrylamide and methacrylamide also affected the dynamic release of riboflavin. It was found that variation in transit time could also affect the drug‐releasing capacity of the devices. Finally, the average and ‘late‐time’ diffusion coefficients for the gels having different initial loads were also evaluated. Copyright © 2004 Society of Chemical Industry
Statistical exploration of variation in quantitative two‐dimensional gel electrophoresis data
Authors: Gustafsson John S. , Ceasar Robert , Glasbey Chris A. , Blomberg Anders , Rudemo Mats 
Published: September 2004

AbstractTwo‐dimensional gel electrophoresis is a major technique in global analysis at the protein level. This paper presents an examination of spot volume data from three gel sets with radioactively labeled yeastSaccharomyces cerevisiaeproteins. A strong varianceversusmean dependence in data was found to be stabilized by applying a shifted logarithmic transformation. However, transformed data showed a remaining substantial variance heterogeneity for different proteins. Furthermore, examination of studentized residuals revealed that transformed data were approximately normally distributed and that there were spatial correlations among the measurement errors in the gel.
Proteomic analysis distinguishes basaloid carcinoma as a distinct subtype of nonsmall cell lung carcinoma
Authors: Li Long Shan , Kim Hyunki , Rhee Hwanseok , Kim Se Hoon , Shin Dong Hwan , Chung Kyung Young , Park Kang‐Sik , Paik Young‐Ki , Chang Joon , Kim Hoguen 
Published: September 2004

AbstractThe histopathologic type of lung cancer is known to be correlated with tumor behavior and prognosis. However, this classification is subjective and no specific molecular markers have been identified. The aim of this study was to identify protein markers in different types of nonsmall cell lung cancers. Two‐dimensional polyacrylamide gel electrophoresis analysis was performed with paired samples of three squamous cell carcinomas, three adenocarcinomas, four large cell carcinomas, and four basaloid carcinomas. We found that 25 proteins in 14 cases of lung cancer were differentially expressed compared to matched nontumorous lung tissues. Among these 25 proteins, 11 proteins were down‐regulated and 14 were up‐regulated in these four types of lung cancer. Alloalbumin venezia, selenium‐binding protein 1, carbonic dehydratase, heat shock 20KD‐like protein, and SM22 α protein were down‐regulated in all 14 cases of lung cancer examined, whereas alpha enolase was consistently up‐regulated. Supervised hierarchical cluster analysis based on the 25 differentially expressed proteins showed that basaloid carcinoma formed one independent group, whereas the other three cancer types were not uniquely classifiable. Our findings suggest that basaloid carcinoma is a unique subtype of nonsmall cell lung carcinoma.
Restoration of heat shock protein70 suppresses gastric mucosal inducible nitric oxide synthase expression induced by Helicobacter pylori
Authors: Yeo Marie , Park Hyun‐kyung , Kim Dong‐Kyu , Cho Sung Won , Kim Young Suk , Cho Sang Yun , Paik Young‐ki , Hahm Ki‐Baik 
Published: September 2004

AbstractHeat shock proteins (HSPs) are crucial for the maintenance of cell integrity during normal cellular growth as well as during pathophysiological conditions. While functioning mainly as molecular chaperones, HSPs also appear to be involved in diverse biological activities, such as apoptosis, carcinogenesis, and cytoprotection from cytotoxic damage. Infection with Helicobacter pylori causes inflammation in the gastric mucosa, leading to gastritis, gastric ulcers, duodenal ulcer disease, and even gastric cancer, but the role of HSPs in H. pylori‐associated gastropathy is not known. Using two‐dimensional electrophoretic analysis, we have observed significant shifts in HSP profiles after H. pylori infection in RGM‐1 cells. We therefore evaluated the effect of treatments that induce HSPs on H. pylori‐induced inducible nitric oxide synthase (iNOS) expression. We found that H. pylori infection significantly attenuated the expression of HSP70, whereas exposure of cells to noncytotoxic heat shock or geranylgeranylacetone restored HSP70 expression, as well as suppressing the expression of iNOS, a major cause of H. pylori‐induced gastric tissue damage. Our results suggest that induction of HSP70 confers cytoprotection against H. pylori infection by inhibiting the expression of iNOS. In conclusion, these results provide important insights into the flux in HSPs profiles in response to H. pylori infection and highlight the cytoprotective role of HSP70 in H. pylori infection.
Lipid raft proteome reveals ATP synthase complex in the cell surface
Authors: Bae Tae‐Jung , Kim Min‐Sik , Kim Jun‐Woo , Kim Bong‐Woo , Choo Hyo‐Jung , Lee Joong‐Won , Kim Ki‐Bum , Lee Chang Seok , Kim Ji‐Hyun , Chang Sun Young , Kang Chang‐Yuil , Lee Sang‐Won , Ko Young‐Gyu 
Published: September 2004

AbstractSince detergent‐resistant lipid rafts are involved in pathogen invasion, cholesterol homeostasis, angiogenesis, neurodegenerative diseases and signal transduction, protein identification in the rafts could provide important information to study their function. Here, we analyzed detergent‐resistant raft proteins isolated from rat liver by capillary liquid chromatography‐tandem mass spectrometry. Out of 196 proteins identified, 32% belonged to the raft or plasma membrane, 24% to mitochondrial, 20% to microsomal, 7% to miscellaneous, and 17% are unknown proteins. For example, membrane‐bound receptors, trimeric GTP‐binding proteins, ATP‐binding cassette transporters, and glycosylphosphatidylinositol‐anchored proteins were identified in this analysis. Unexpectedly, there were many mitochondrial proteins, raising a new issue for the presence of mitochondrial rafts or the localization of mitochondrial proteins into plasma membrane rafts. We confirmed that ATP synthase α and β were expressed on the surface of the plasma membrane in HepG2 hepatocytes by immunofluorescence, cell surface biotinylation, and cellular fractionation. They had two distinct biochemical properties, detergent insolubility and low density, suggesting that the ATP synthase complex might be located in plasma membrane rafts as well as in the mitochondria.
Profiling proteins related to amyloid deposited brain of Tg2576 mice
Authors: Shin Su Jeon , Lee Sung‐Eun , Boo Jung Hyun , Kim Mihyang , Yoon Young‐Dae , Kim Su‐il , Mook‐Jung Inhee 
Published: September 2004

AbstractAlzheimer's disease (AD) is an age‐related neurodegenerative disorder that is characterized by the extracellular deposition of β‐amyloid and intracellular hyperphosphorylation of tau in the cortex and hippocampus of the brain. These characterizations are caused by abnormal expression, modification and deposition of certain proteins. Post‐translational modifications of proteins including oxidation and nitration might be involved in the pathogenesis of AD. In this study, AD‐related proteins were identified in the cortex of Tg2576 mice used as a model for studying AD. Tg2576 mice express high levels of the Swedish mutated form of human β‐amyloid precursor protein (APP) and generated high levels of β‐amyloid in the brains. Using Western blotting and two‐dimensional electrophoresis, proteins with differences in expression, oxidation and nitration in the cortex of Tg2576 mice brains were compared to littermate mice brains used as a control. The proteins with different expression levels were identified using matrix‐assisted laser desorption/ionization‐time of flight and liquid chromatography‐tandem mass spectrometry analyses. As a result, 12 proteins were identified among 37 different proteins using the PDQuest program. Furthermore, two proteins, laminin receptor and α‐enolase, were more susceptible to oxidative modification in the brains of Tg2576 mice compared to those of littermates. Similarly, α‐enolase, calpain 12, and Atp5b were more modified by nitration in brains of Tg2576 mice than those of littermates. Taken together, these proteins and their modifications may play an important role in the plaque deposition of Tg2576 mice brains.
Proteome analysis of rice blast fungus (Magnaporthe grisea) proteome during appressorium formation
Authors: Kim Sun Tae , Yu Seok , Kim Sang Gon , Kim Han Ju , Kang Sun Young , Hwang Du Hyeon , Jang Yu Sin , Kang Kyu Young 
Published: September 2004

AbstractWe used two‐dimensional gel electrophoresis (2‐DE) to identify the proteins that are induced in the rice blast fungus Magnaporthe grisea during appressorium formation. Proteins were extracted from conidia that had germinated on hydrophilic glass plates or from germinated and appressoria‐forming conidia on leaf wax‐coated hydrophobic glass plates after 4, 8, and 12 h of incubation. Differentially expressed protein spots during appressorium formation were confirmed from gels after 2‐DE analysis where proteins had been labeled with 35S methionine and stained with silver. Internal amino acid sequencing identified five proteins among several proteins induced during appressorium formation. Two denoted as M. grisea proteasome homolgues (MgP1 and MgP5) were 20S proteasome α subunits. The remaining three were scytalone dehydratase (SCD), and serine carboxypeptidase Y (CPY). None of the five have been reported previously in the rice blast fungus apart from SCD. We further investigated the role the α subunit of 20S proteasome plays in appressorium formation. We confirmed by Western blot analysis that MgP5 is highly expressed during appressorium formation and found that it is also markedly induced by nitrogen‐ and carbon‐starvation, in particular by the former. These observations suggest that the 20S proteasome may be involved in remobilizing storage proteins, which then help to build the appressorium. Thus, fungal proteome analysis may provide important clues about developmental changes such as the generation of the appressorium.