bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on Effects of Polydispersity on the Form Factor and Depletion Interaction in Colloid‐Polymer Mixtures with Laser Distribution
Authors: Foroutan Massumeh , Jafarizadeh Mohammad A. 
Published: November 2004

AbstractSummary: We investigate the influence of the polydispersity of colloidal particles and polymer, respectively, on the form factor and depletion interaction by using the laser distribution for parallel plates immersed in a solution of nonadsorbing polymers. For colloidal particles, we show that the measurement of scattering intensity of a polymer‐colloid mixture can be described qualitatively in terms of the parameters K and M of the laser distribution. The form factor of the monodisperse system varies considerably, but generally stays close to the average value that corresponds to the form factor of polydisperse system. By using the laser distribution in the chain length of polymers, we present the complex polymer segment density of polymer chain between particles with the product‐function approximation comprehensively and accurately. In particular, we find that for small values of parameter M, the change of values of parameter K has no effect on depletion interaction.Predicted form factor for polydisperse core‐shell particles.magnified imagePredicted form factor for polydisperse core‐shell particles.
Chains in Critical Fluids and Nanopores
Authors: Negadi Amina , Dua Arti , Vilgis Thomas A. 
Published: November 2004

AbstractSummary: The conformational behavior of a polymer in a critical binary solvent confined in a porous medium is studied. The size of the polymer in bulk, which is mainly governed by the correlation length of the solvent density fluctuations, depends on the proximity to the critical point of the binary mixture. We find that in contrast to the bulk behavior, the conformational properties of the polymer in a porous medium depends strongly on the pore size. The latter controls the correlation length of the solvent density fluctuations and thus determines the polymer size.
A Probability Model of Star‐Branched Polymers Formed by Connecting Polydispersed Primary Chains Onto a Multifunctional Coupling Agent
Authors: Shiau Lie‐Ding 
Published: November 2004

AbstractSummary: A probability model, based on the “in‐out” recursive analysis, is developed for obtaining the average molecular weights of star polymers formed by connecting polydispersed primary chains onto a multifunctional coupling agent. The average properties and the polydispersity index of the formed star polymers can be described as a function of the reaction conversion and the average properties of the polydispersed primary chains without the knowledge of the whole distribution. The results indicate that, although PI of the resulting star polymers might increase at the intermediate conversion for the higher functionalities of the core molecules, the resulting star polymers generally have narrower molecular weight distributions at the complete conversion compared to the initial polydispersed polymer chains.A schematic illustration of the star polymer formation.magnified imageA schematic illustration of the star polymer formation.
Visualizing feature evolution of large‐scale software based on problem and modification report data
Authors: Fischer Michael , Gall Harald 
Published: November 2004

AbstractGaining higher‐level evolutionary information about large software systems is a key challenge in dealing with increasing complexity and architectural deterioration. Modification reports and problem reports (PRs) taken from systems such as the concurrent versions system (CVS) and Bugzilla contain an overwhelming amount of information about the reasons and effects of particular changes. Such reports can be analyzed to provide a clearer picture about the problems concerning a particular feature or a set of features. Hidden dependencies of structurally unrelated but over time logically coupled files exhibit a good potential to illustrate feature evolution and possible architectural deterioration. In this paper, we describe the visualization of feature evolution by taking advantage of this logical coupling introduced by changes required to fix a reported problem. We compute the proximity of PRs by applying a standard technique called multidimensional scaling (MDS). The visualization of these data enables us to depict feature evolution by projecting PR dependence onto (a) feature‐connected files and (b) the project directory structure of the software system. These two different views show how PRs, features and the directory tree structure relate. As a result, our approach uncovers hidden dependencies between features and presents them in an easy‐to‐assess visual form. A visualization of interwoven features can indicate locations of design erosion in the architectural evolution of a software system. As a case study, we used Mozilla and its CVS and Bugzilla data to show the applicability and effectiveness of our approach. Copyright © 2004 John Wiley & Sons, Ltd.
Monetary union and the Maastricht inflation criterion: The accession countries*
Authors: Ozkan F. Gulcin , Sibert Anne , Sutherland Alan 
Published: November 2004

AbstractWe model an accession country facing a Maastricht‐type inflation criterion that specifies an inflation ceiling. In addition to deciding whether or not to satisfy this criterion, the country must decide how much costly economic reform to undertake. If the country puts enough weight on the future that it can credibly meet the inflation criterion no matter what the ceiling is, then the inflation criterion benefits the country but lowers reform. If the country puts less weight on the future, then a criterion with a properly chosen inflation ceiling can increase reform. We derive the inflation ceilings that maximize the country's welfare and its reform.
The optimality and overuse of labour in Estonian manufacturing enterprises*
Authors: Masso Jaan , Heshmati Almas 
Published: November 2004

AbstractTransition economies need labour market flexibility for successful restructuring and reallocation of the labour force, and for coping with the requirements of the European Monetary Union. In this paper we apply a novel approach to the issue of labour market flexibility in transition countries by studying the optimality and efficiency of labour usage in Estonian manufacturing enterprises. We employ a dynamic model in which both the long‐run optimal level of employment and the speed at which actual employment is adjusted to the optimal are modelled as functions of several variables. Firm‐level panel data of 1995–99 were used. The results showed that in the long run, employment responds most strongly to wages, followed by value added and capital stock. The speed of adjustment, labour use optimality and efficiency all show much greater variations over firms than over time. In the course of time, both labour‐saving technical change and an increase in the efficiency of labour usage occur. On average, there is shortage of labour compared to firms’ own optimal level, along with overuse of labour compared to best‐practice technology. Capital seems to be a binding constraint on the development of employment in the Estonian labour market.
Postoperative complications after CS spray exposure
Authors: Davey A. , Moppett I. K. 
Published: November 2004

SummaryWe report on airway complications associated with general anaesthesia in a subject who had been exposed to CS spray several hours before surgery. CS spray is a form of tear gas that is said to have a short half‐life when the subject is removed from exposure. Induction of anaesthesia was uneventful. Marked laryngospasm occurred when the tracheal tube was removed at the end of the operation, and the anaesthetists experienced lacrimation and burning sensations typical of CS exposure. The effects on the attending anaesthetist made tracheal re‐intubation difficult. There were no long‐term adverse sequelae for the patient or anaesthetists. Suggestions are made for changes to anaesthetic practice and the advice given by the police about patients who have been exposed to CS spray.
Tracheal intubation using the Bonfils intubation fibrescope after failed direct laryngoscopy*
Authors: Bein B. , Yan M. , Tonner P. H. , Scholz J. , Steinfath M. , Dörges V. 
Published: November 2004

SummaryFailed tracheal intubation due to a difficult airway is an important cause of anaesthetic morbidity and mortality. This study was undertaken to evaluate the effectiveness of the Bonfils intubation fibrescope for tracheal intubation after failed direct laryngoscopy. Twenty‐five patients undergoing coronary artery bypass grafting were enrolled in the study after two attempts at conventional laryngoscopy by a board certified anaesthetist had failed. Intubation with the Bonfils fibrescope was successful on the first attempt in 22 patients (88%) and on the first or second attempt in 24 patients (96%); in one patient intubation was impossible. Median (IQR [range]) time to intubation using the Bonfils intubation fibrescope was 47.5 (30–80 [20–200]) s. Tracheal intubation using the Bonfils intubation fibrescope appears to be a simple and effective technique for the management of a difficult intubation.
Antigen presentation by MART‐1 adenovirus‐transduced interleukin‐10‐polarized human monocyte‐derived dendritic cells
Authors: Mehrotra Shikhar , Chhabra Arvind , Chakraborty Abolokita , Chattopadhyay Subhasis , Slowik Mark , Stevens Robert , Zengou Ryan , Mathias Clinton , Butterfield Lisa H. , Dorsky David I. , Economou James S. , Mukherji Bijay , Chakraborty Nitya G. 
Published: November 2004

SummaryDendritic cells (DC) play critical roles in generating an immune response and in inducing tolerance. Diverse microenvironmental factors can ‘polarize’ DC toward an immunogenic or non‐immunogenic phenotype. Among the various microenvironmental factors, interleukin‐10 (IL‐10) exhibits a potent immunosuppressive effect on antigen‐presenting cells (APC). Here, we show that monocyte‐derived DC generated in the presence of IL‐10 exhibit a profound down‐regulation of many genes that are associated with immune activation and show that the IL‐10‐grown DC are poor stimulators of CD8+ T cells in a strictly autologous and major histocompatibility complex (MHC) class I‐restricted melanoma antigen recognized by T cells (MART‐1) epitope presentation system. However, these IL‐10‐grown DC can efficiently activate the epitope‐specific CD8+ T cells when they are made to present the epitope following transduction with an adenoviral vector expressing the MART‐1 antigen. In addition, we show that the MART‐1 protein colocalizes with the MHC class I protein, equally well, in the iDC and in the DC cultured in presence of IL‐10 when both DC types are infected with the viral vector. We also show that the vector transduced DC present the MART‐127−35 epitope for a sustained period compared to the peptide pulsed DC. These data suggest that although DCs generated in the presence of IL‐10 tend to be non‐immunogenic, they are capable of processing and presenting an antigen when the antigen is synthesized within the DC.
Major histocompatibility complex class I–intercellular adhesion molecule‐1 association on the surface of target cells: implications for antigen presentation to cytotoxic T lymphocytes
Authors: Lebedeva Tatiana , Anikeeva Nadja , Kalams Spyros A. , Walker Bruce D. , Gaidarov Ibragim , Keen James H. , Sykulev Yuri 
Published: November 2004

SummaryPolarization and segregation of the T‐cell receptor (TCR) and integrins upon productive cytotoxic T‐lymphocyte (CTL) target cell encounters are well documented. Much less is known about the redistribution of major histocompatibility complex class I (MHC‐I) and intercellular adhesion molecule‐1 (ICAM‐1) proteins on target cells interacting with CTLs. Here we show that human leucocyte antigen‐A2 (HLA‐A2) MHC‐I and ICAM‐1 are physically associated and recovered from both the raft fraction and the fraction of soluble membranes of target cells. Conjugation of target cells with surrogate CTLs, i.e. polystyrene beads loaded with antibodies specific for HLA‐A2 and ICAM‐1, induced the accumulation of membrane rafts, and beads loaded with ICAM‐1‐specific antibodies caused the selective recruitment of HLA‐A2 MHC‐I at the contact area of the target cells. Disruption of raft integrity on target cells led to a release of HLA‐A2 and ICAM‐1 from the raft fraction, abatement of HLA‐A2 polarization, and diminished the ability of target cells bearing viral peptides to induce a Ca2+ flux in virus‐specific CTLs. These data suggest that productive engagement of ICAM‐1 on target cells facilitates the polarization of MHC‐I at the CTL–target cell interface, augmenting presentation of cognate peptide–MHC (pMHC) complexes to CTLs. We propose that ICAM‐1–MHC‐I association on the cell membrane is a mechanism that enhances the linkage between antigen recognition and early immunological synapse formation.
Epitope‐specific crosslinking of CD45 down‐regulates membrane‐associated tyrosine phosphatase activity and triggers early signalling events in human activated T cells
Authors: Spertini François , Perret‐Menoud Veronique , Barbier Nathalie , Chatila Talal , Barbey Catherine , Corthesy Blaise 
Published: November 2004

SummaryCD45 engagement by monoclonal antibodies on human activated T cells triggers tumour necrosis factor‐α (TNF‐α) gene transcription in an epitope‐specific manner. To dissect the early signalling events leading to TNF‐α gene expression, we established that CD45 crosslinking resulted in tyrosine phosphorylation of p56lck, ZAP‐70, CD3‐ζ, LAT and Vav. This was accompanied by down‐regulation of membrane‐associated protein tyrosine phosphatase activity in the absence of demonstration of enhanced p56lck, p72syk and ZAP‐70 kinase activity, which remained constitutive. These early events eventually triggered an intracellular Ca2+ rise and phosphoinositide turnover. We conclude that down‐regulation of membrane‐associated tyrosine phosphatase activity by CD45 extracytoplasmic domain multimerization led, in an epitope‐specific fashion, to unopposed tyrosine kinase activity and to the activation of the T‐cell receptor/CD3 complex signalling cascade, resulting in TNF‐α gene expression. This model strongly suggests that CD45 extracytoplasmic tail multimerization may contribute to the modulation T‐cell functions.
In vivo exposure of murine dendritic cell and macrophage bone marrow progenitors to the phosphorylcholine‐containing filarial nematode glycoprotein ES‐62 polarizes their differentiation to an anti‐inflammatory phenotype
Authors: Goodridge Helen S. , Marshall Fraser A. , Wilson Emma H. , Houston Katrina M. , Liew Foo Y. , Harnett Margaret M. , Harnett William 
Published: November 2004

SummaryWe have previously shown in an in vitro study that the filarial nematode phosphorylcholine (PC)‐containing glycoprotein ES‐62 promotes a murine dendritic cell (DC) phenotype that induces T helper type 2 (Th2) responses. We now show that, in addition to directly priming Th2 responses, ES‐62 can act to dampen down the pro‐inflammatory DC responses elicited by lipopolysaccharide. Furthermore, we also demonstrate that murine DCs and macrophages derived ex vivo from bone marrow cells exposed in vivo to ES‐62 by release from osmotic pumps are hyporesponsive to subsequent stimulation with lipopolysaccharide. These effects can be largely mimicked by exposure to the PC moiety of ES‐62 conjugated to an irrelevant protein. The data we provide are, as far as we aware, the first to show that a defined pathogen product can modulate the developmental pathway of bone marrow cells of the immune system in vivo. Such a finding could have important implications for the use of pathogen products or their derivatives for immunotherapy.
Reduction of connexin 43 expression in aged human dental pulp
Authors: Muramatsu T. , Hamano H. , Ogami K. , Ohta K. , Inoue T. , Shimono M. 
Published: November 2004

AbstractAim  To investigate the expression of connexin 43 (CX43) mRNA in young and old human dental pulp tissues to determine the characteristics of CX43 expression.Methodology  Samples were obtained from human dental pulp of healthy young (17–23 years) and aged (>50 years) subjects. CX43 expression was determined by RT‐PCR and by quantitative real‐time RT‐PCR (QRT‐PCR). The threshold cycle (Ct) value, which reflects the amount of PCR, was calculated and the difference between value in the young pulp and that in the aged pulp was statistically analysed.Results  RT‐PCR analysis of human dental pulp tissue detected CX43 mRNA in all the samples. CX43 was abundantly expressed in young adult dental pulp, but expression of CX43 mRNA was dramatically decreased in aged human dental pulp. QRT‐PCR analysis also showed the reduced expression of CX43 in aged pulp, and expression of CX43 in young pulp was significantly higher (about 10‐fold, P < 0.01, Mann–Whitney U‐test).Conclusion  Reduction of CX43 expression may be associated with the loss of viability in human dental pulp, and is considered as one characteristic of aged pulp.
Investigation of the effect of the coronal restoration quality on the composition of the root canal microflora in teeth with apical periodontitis by means of T‐RFLP analysis
Authors: Hommez G. M. G. , Verhelst R. , Claeys G. , Vaneechoutte M. , De Moor R. J. G. 
Published: November 2004

AbstractAim  To investigate the effect of the radiographic and clinical quality of coronal restorations on the composition of the root canal flora of teeth with necrotic pulps and teeth with root fillings associated with apical periodontitis.Methodology  Twenty‐eight necrotic pulps and 35 root filled canals with signs of apical periodontitis were studied. Both the coronal filling (presence of radiographically or clinically deficient margins and/or secondary caries) and the root filling (homogeneity and length) were scored. Bacterial root canal samples were taken with sterile paper points under rubber dam and using measures to prevent contamination. A DNA‐based nonculture bacterial identification technique was used, namely terminal restriction fragment length polymorphism (T‐RFLP) analysis.Results  Twelve samples were negative for bacterial DNA. A total of 33 different terminal restriction fragments (TRFs) were detected. The Fusobacterium nucleatum/Streptococcus mitis group was the most frequently encountered TRF. The mean number of TRFs per necrotic pulp was 6.2 and 5.8 for the groups with acceptable and unacceptable coronal restorations, respectively. This difference was not significant. In the root filled group, these values (respectively, 5.2 and 8.6) were statistically significantly different (P < 0.05). The following parameters in root filled teeth had no significant influence on the mean numbers of TRFs detected: the length and homogeneity of the root filling and the type of tooth (anterior–premolar–molar).Conclusion  T‐RFLP allowed the rapid assessment of bacterial biodiversity in root canal samples. The technique revealed the presence of bacteria that have rarely been described in the root canals of teeth with apical periodontitis. Biodiversity in the root filled group was high, as compared with culture‐dependent studies where monoinfections were more frequently reported. Only in root filled teeth did defective coronal restorations have a statistically significant influence on the mean numbers of detected TRFs per sample.
A Confocal Laser Scanning Microscope investigation of different dental adhesives bonded to root canal dentine
Authors: Bitter K. , Paris S. , Martus P. , Schartner R. , Kielbassa A. M. 
Published: November 2004

AbstractAim  To evaluate the resin–dentine interface of different adhesive systems and corresponding luting cements proposed for bonding fibre posts to root canal dentine.Methodology  Fifty extracted maxillary canines and central incisors were used. After root canal treatment the teeth were randomly divided into five groups of 10 teeth each. Fibre posts were inserted with five different adhesive systems and corresponding luting cements. Group 1: Clearfil Core/New Bond (Kuraray), group 2: Multilink (Vivadent), group 3: Panavia 21/ED Primer (Kuraray), group 4: PermaFlo DC (Ultradent), and group 5: Variolink II/Excite DSC (Vivadent). The primer was labelled in each case with 0.1% Rhodamine B isothiocyanate (RITC). Each root was sectioned into 2 mm thick slices at 1, 4 and 7 mm below the cementoenamel junction. The resin–dentine interface was evaluated using a Confocal Laser Scanning Microscope; the thickness of the hybrid layer and the number of resin tags were measured. The statistical analysis was performed using nonparametrical tests for comparisons between groups; for overall comparisons the Kruskal–Wallis test was used. Intraindividual analysis within teeth was performed using a linear model.Results  The thickness (μm) of the hybrid layer of group 1 (5.45; SD 1.21), group 4 (3.36; SD 1.59), and group 5 (4.33; SD 1.19) was significantly higher than in the other groups (P ≤ 0.05). The number of resin tags observed in group 1 was significantly higher than in groups 2–4 (P < 0.05), but did not differ from group 5. Each group showed significantly more resin tags in the coronal and in the central part of the root canal than in the apical part (P < 0.001).Conclusion  Conditioning of the root canal dentine with phosphoric acid and the use of one‐ and two‐bottle‐bonding systems gave a thicker and more uniform hybrid layer with considerably more resin tags than observed after the use of ‘self‐etching’ adhesives. This might provide a more durable bond of the post to root canal dentine.
Identification of an Arabidopsis thaliana gene encoding a plasma membrane H+‐ATPase whose expression is restricted to anther tissues
Authors: Houlné G. , Boutry M. 
Published: November 2004

SummaryA gene (aha9) for a plasma membrane H+‐ATPase was isolated from an Arabidopsis thaliana genomic library and sequenced. Comparison of the aha9 predicted amino acid sequence with those of aha1, 2 and 3 and analogous genes from other species indicated the existence of at least two aha gene subfamilies whose divergence precedes that of the Nicotiana and Arabidopsis species. Transcript analysis in various organs revealed expression of aha9 in flower tissues only. Introduction of aha9 into Nicotiana tabacum by genetic transformation gave rise to transgenic plants which also express aha9 in flower tissues. A more detailed analysis showed that aha9 expression was restricted to anther tissues.
A light‐responsive in vitro transcription system from evacuolated parsley protoplasts
Authors: Frohnmeyer Hanns , Hahlbrock Klaus , Schafer Eberhard 
Published: November 2004

SummaryEvacuolated protoplasts (EP) retain transcriptional activity responding, after UV‐light treatment, to the expression of chalcone synthase (CHS); this behaviour is similar to the parsley cell culture and protoplasts from which the EP were derived. Chemical lysis of the EP with low concentrations of a detergent in a minimal volume had no negative effect on the inducibility of CHS by UV‐containing white light. Based on these observations a new method is presented here for establishing a light‐responsive in vitro transcription system from evacuolated protoplasts of a parsley (Petroselinum crispum) cell culture. A 615 bp promoter fragment of the CHS gene, fused to the β‐Glucuronidase (GUS) reporter gene, was accurately transcribed as in transiently transformed protoplasts and the reaction was highly sensitive to α‐amanitin. A 226 bp CHS promoter/GUS reporter construct with mutated cis‐acting elements was unable to stimulate GUS transcription, whilst a 341 bp 35S‐promoter from the cauliflower mosaic virus (CaMV) was constitutively expressed in dark‐ or light‐treated lysates. The expression of the CHS full‐length promoter/GUS construct in the cell‐free system was three‐fold increased by white or red light compared with the dark level. These results demonstrate that within this in vitro system there must exist a largely intact signal transduction chain between photoreceptor(s) and the CHS promoter. As such it will be a valuable tool for elucidating signalling mechanisms and functional assays of trans‐acting factors acting at the end of the pathway.