bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methylated and pegylated PLA–PCL–PLA block copolymers via the chemical modification of di‐hydroxy PCL combined with the ring opening polymerization of lactide
Authors: Huang Ming‐Hsi , Coudane Jean , Li Suming , Vert Michel 
Published: August 2005

AbstractMethylated and pegylated poly(lactide)‐block‐poly(ε‐caprolactone)‐block‐poly(lactide) copolymers, PLA–P(CL‐co‐CLCH3)–PLA and PLA–P(CL‐co‐CLPEG)–PLA, were prepared in three steps: combining the formation of carbanion‐bearing dihydroxylated‐PCL, the coupling of iodomethane or bromoacetylated α‐hydroxyl‐ω‐methoxy‐poly(ethylene glycol) onto the carbanionic PCL, and finally the ring opening polymerization of DL‐lactide initiated by the preformed grafted diOH‐PCL copolymers. The resulting block copolymers exhibited lower crystallinity, melting temperature, and hydrophobicity with respect to the original PCL. Degradation of the grafted copolymers was investigated in the presence of Pseudomonas cepacia lipase and compared with that of the triblock copolymer precursor. It is shown that the presence of the grafted substituents affected the enzymatic degradation of PCL segments. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4196–4205, 2005
The role of calcium in the conformational dynamics and thermal stability of the D‐galactose/D‐glucose‐binding protein from Escherichia coli
Authors: Herman Petr , Vecer Jaroslav , Barvik Ivan , Scognamiglio Viviana , Staiano Maria , de Champdoré Marcella , Varriale Antonio , Rossi Mose' , D'Auria Sabato 
Published: August 2005

AbstractWe have characterized stability and conformational dynamics of the calcium depleted D‐galactose/D‐glucose‐binding protein (GGBP) from Escherichia coli. The structural stability of the protein was investigated by steady state and time resolved fluorescence, and far‐UV circular dichroism in the temperature range from 20°C to 70°C. We have found that the absence of the Ca2+ ion results in a significant destabilization of the C‐terminal domain of the protein. In particular, the melting temperature decreases by about 10°C with the simultaneous loss of the melting cooperativity. Time resolved fluorescence quenching revealed significant loosening of the protein when highly shielded Trp residue(s) became accessible to acrylamide at higher temperatures. We have documented a significant stabilizing effect of glucose that mostly reverts the effect of calcium, that is, the thermal stability of the protein increases by about 10°C and the melting cooperativity is restored. Moreover, the protein structure remains compact with low amplitude of the segmental mobility up to high temperatures. We have used molecular dynamics to identify the structural feature responsible for changes in the temperature stability. Disintegration of the Ca2+‐binding loop seems to be responsible for the loss of the stability in the absence of calcium. The new insights on the structural properties and temperature stability of the calcium depleted GGBP contribute to better understanding of the protein function and constitute important information for the development of new biotechnological applications of this class of proteins. Proteins 2005. © 2005 Wiley‐Liss, Inc.
A membrane model of electrically remodelled atrial myocardium derived from in vivo measurements*
Authors: Goodman Amy M. , Oliver Robert A. , Henriquez Craig S. , Wolf Patrick D. 
Published: August 2005

Abstract

Aims
Contemporary ionic-based membrane models are computationally expensive and are not intended to match the properties of a given experimental preparation. The aim of this work was to use measured restitution properties of electrically remodelled atrial tissue to develop a simplified membrane model based on the Fenton–Karma (FK) equations amenable to large-scale simulation of chronic atrial fibrillation (CAF).

Methods
Two membrane models, the FK-CAF and FK-CNTRL parameter sets, were developed to match action potential duration (APD) and conduction velocity (CV) restitution properties of rapid-pacing-induced electrically remodelled sheep atria and healthy atria, respectively. The models were tested by inducing reentry in a two-dimensional anisotropic monodomain and comparing the resulting cycle lengths (CL) with measured CLs.

Results
Parameters for the FK models were obtained that reproduced APD and CV restitution properties measured in the CAF and healthy sheep atria. Using the FK-CAF parameters, reentry was sustained in a 2.5 by 2.5 cm sheet with a CL = 91.0 ± 3.0 ms. Reentry (CL = 113.2 ± 5.2 ms) could only be sustained in the FK-CNTRL model after the tissue was first activated at a fast rate (136.5 ms).

Conclusions
The FK-CAF model is shown to approximate the restitution properties of remodelled sheep atria and can be used to simulate reentry with short CLs similar to those measured during AF episodes.
Small-scale spatio-temporal variability in ichthyoplankton and zooplankton distribution in relation to a tidal-mixing front in the Irish Sea
Authors: Lee O. , Nash R.D.M. , Danilowicz B.S. 
Published: August 2005

Abstract
This study examines the spatio-temporal dynamics of fish larvae and their prey at a tidal-mixing front in the central Irish Sea. The distribution of ichthyoplankton and zooplankton was analysed in relation to environmental variables (depth, surface temperature, surface salinity, and water column stratification) using Redundancy Analysis (RDA). Significant interannual variability in the formation and position of the tidal-mixing front coincided with large differences in the species abundances of both ichthyoplankton and zooplankton. During the summer, ichthyoplankton and zooplankton communities were structured by a combination of depth and hydrography, and the variability in species composition was directly related to the average value of the stratification parameter. Several ichthyoplankton species were consistently associated with frontal waters, while fewer species were concentrated in mixed water masses throughout the sampling period. The distribution of individual zooplankton species was also examined, and water mass affinities were shown to vary with developmental stage.
Studying the consequences of immediate loss of gene function in the intestine: APC
Authors: Clarke A.R. 
Published: August 2005

The use of mouse models to study neoplasia is proving particularly powerful in dissecting the mechanisms underlying disease initiation and progression. However, the majority of these models have been somewhat limited in studying the very early effects of loss of gene function, as tumour initiation relies upon either constitutive loss of gene function or spontaneous somatic loss of function. We have therefore adopted a strategy of using an inducible Cre-lox-based system to analyse the effects of loss of gene function, the use of which is reviewed here for the intestinal tumour suppressor APC (adenomatous polyposis coli). Using this approach, we have conditionally and synchronously inactivated APC in virtually all the epithelial cells of the adult murine small intestine. After 5 days following induction of Cre-mediated recombination, mice show grossly altered crypt/villus architecture. Deficiency in APC perturbs migration, alters the normal programme of differentiation and results in increased proliferation and apoptosis. Microarray analysis reveals the transcriptome to be significantly altered; reflecting both gross phenotypic changes and changes in transcriptional activation. These findings demonstrate that APC is indeed the critical determinant of cell fate in the intestinal epithelium, explaining its role as the cellular ‘gatekeeper’ in preventing neoplasia.
Design of a MUC1-based cancer vaccine
Authors: Hanisch F.-G. 
Published: August 2005

The epithelial type 1 transmembrane mucin MUC1 is long-established as a marker for monitoring recurrence of breast cancer, and beyond its diagnostic marker qualities, it is a promising target for immunotherapeutic strategies to treat cancer by active specific immunization. The mucin is able to break tolerance and to induce humoral immune responses in healthy subjects and in cancer patients, but the response is generally weak. These natural responses to tumour-associated MUC1 glycoforms indicate that antibody reactivities are more directed to glycopeptide than to non-glycosylated peptide epitopes. To overcome the weak immunogenicity of heavily O-glycosylated MUC1, the question of whether O-linked glycans remain intact during processing in the MHC class II pathway was addressed. Attempts were made to define site-specific O-glycosylation and the structural requirements for efficient endosomal proteolysis by cathepsin L in dendritic cells. A fraction of glycopeptides survive the processing machinery, and have the capacity to bind to MHC class II and to activate sub-populations of glycopeptide-specific helper T-cell clones as a prerequisite for strong and long-lasting immune responses to MUC1-positive tumours. Moreover, studies on clusters of sequence-variant repeats, which are interspersed in the repeat domain of MUC1 at high frequency, have revealed that a limited set of concerted amino-acid replacements (Asp-Thr0-Arg1–Pro10 to Glu-Ser0-Arg1–Ala10) contributes considerably to increased peptide flexibility and to under-glycosylation of sequence-variant repeats which in concert modify immunological features of the mucin. Peptides and glycopeptides with the immunodominant DTR (Asp-Thr-Arg) or with the variant ESR (Glu-Ser-Arg) motif, and highly immunogenic peptides of the degenerate repeats that flank the repeat domain are currently evaluated as potential targets in multi-epitopic adjuvant-based vaccine strategies for their capacity to induce cytotoxic T-cell responses.
E‐only journals: is it time to drop print?
Authors: Ware Mark 
Published: August 2005

ABSTRACTThis article is a revised version of a talk given at the ALPSP seminar of the same name in February 2005. The current state of play with electronic‐only (‘e‐only’) journals is reviewed, along with some data on the different ways print and electronic editions are used. The drivers for and against a move to e‐only journals are discussed, including economic and commercial issues, long‐term access and preservation, and the growing divergence between the capabilities of print and electronic journals.
Running exercise of different duration and intensity: effect on endothelial progenitor cells in healthy subjects
Authors: Laufs Ulrich , Urhausen Axel , Werner Nikos , Scharhag Jürgen , Heitz Anja , Kissner Gerrit , Böhm Michael , Kindermann Wilfried , Nickenig Georg 
Published: August 2005

Background Increased numbers of circulating endothelial progenitor cells (EPC) are associated with improved vascular function. Exercise is a central component of the primary prevention of vascular diseases. The effect of physical activity on circulating EPC in healthy individuals is not known. Design A prospective crossover study. Methods and results In order to study a potential link between the extent of physical exercise and progenitor cells in humans, EPC were quantified by flow cytometry and cell culture in 25 healthy volunteers undergoing three protocols of running exercise. Intensive running, defined as 30 min at 100% of the velocity of the individual anaerobic threshold (IAT; ∼82% maximal oxygen consumption; VO2max), as well as moderate running with 30 min at 80% of the velocity of the IAT (∼68% VO2max), increased circulating EPC numbers to 235±93% and 263±106% of control levels, respectively. However, moderate short-term running for 10 min did not upregulate EPC counts. The maximum increase in circulating EPC numbers was observed 10–30 min after intensive running. Exercise increased EPC migratory and colony-forming capacity. Conclusions Intensive and moderate exercising for 30 min, but not for 10 min, increased circulating levels of EPC, which may represent an important beneficial outcome of physical exercise. The data support the notion that increased numbers of EPC correlate with cardiovascular health and suggest EPC quantification as a novel surrogate parameter of the vascular effects of exercising.
Sheepskin effects in Japan
Authors: Bauer Thomas K. , Dross Patrick J. , Haisken‐DeNew John P. 
Published: August 2005

PurposeThe purpose of this paper is to examine the role of sheepskin effects in the return to education in Japan.Design/methodology/approachThe paper provides a short description of the Japanese schooling and recruitment system. It then describes the data set and the empirical approach. Estimation results are presented for the various specifications. The baseline specification closely follows existing studies for the USA to facilitate comparability across the two countries. The paper further investigates whether there are significant firm‐size differences in the estimated sheepskin effects and whether sheepskin effects disappear with increasing job tenure.FindingsThe estimation results indicate that sheepskin effects explain about 50 percent of the total returns to schooling. The paper further finds that education as a signal is only important for workers in small firms with the size of these effects being similar to comparable estimates for the USA. Finally, the estimated degree effects decrease with firm tenure, in particular for small firms. These results could be explained by the particular recruitment system of large firms in Japan, which makes university diploma as a screening device unimportant for large firms and the admission policy of Japanese universities.Originality/valueBy investigating the role of sheepskin effects in a labor market that differs substantially from the labor market in the USA, the paper provides additional insights to the human capital theory‐screening hypothesis debate.
Projections of the future path of the gender wage gap in Great Britain
Authors: Shannon Michael , Kidd Michael P. 
Published: August 2005

PurposeThe paper attempts to project the future trend of the gender wage gap in Great Britain up to 2031.Design/methodology/approachThe empirical analysis utilises the British Household Panel Study Wave F together with Office for National Statistics (ONS) demographic projections. The methodology combines the ONS projections with assumptions relating to the evolution of educational attainment in order to project the future distribution of human capital skills and consequently the future size of the gender wage gap.FindingsThe analysis suggests that gender wage convergence will be slow, with little female progress by 2031 unless there is a large rise in returns to female experience.Originality/valueThe paper has projected the pattern of male and female skill acquisition together with the associated trend in wages up to 2031.
The impact of capital offering on real estate developers and construction sector stock return in Hong Kong
Authors: Chi Man Hui Eddie , Kwan Wah Wong Francis , Hung Chiang Yat 
Published: August 2005

PurposeNumerous studies suggest that announcements of capital offerings cause abnormal price reaction in stock markets. However, despite extensive research, relevant studies on the property sector are still relatively scarce, especially in the case of Hong Kong. The determinants of the post‐offering price effects, which vary across industries and regions, are yet to be identified. This paper aims to examine the abnormal stock return phenomenon of Hong Kong property developers and construction companies surrounding the announcement and offer dates of capital issuances.Design/methodology/approachIt employs the event‐study methodology and regression analysis to verify such effects.FindingsThe major findings are: on equity offering announcements, there is a significant negative price reaction; the pre‐offering debt/equity ratio of a firm is significantly associated with the level of abnormal price reactions; and on debt offerings there is, to the contrary, a modest increase in stock prices.Practical implicationsThis study has identified a set of determinants of the post‐offering stock price effects.Originality/valueIt can be concluded that there is evidence of abnormal price effects over the announcement and offer dates of capital issuances with unique characteristics of the property and construction sectors in Hong Kong.
Communication capability and attitudes toward external communication of purchasing managers in Germany
Authors: Large Rudolf O. 
Published: August 2005

PurposeManagement approaches, such as supply chain management addressing cooperation among firms emphasize communication among people from different companies. The objective of this research was to investigate the impact of individual and contextual factors on the external communication behavior of purchasing managers in Germany.Design/methodology/approachBased on the literature, oral and written communication capabilities, purchasers' attitudes and the internal communication climate were identified as potential impact factors. A structural equation model containing 11 constructs was designed. Six hundred and seventeen responses were available for statistical analysis.FindingsSumming up the results, oral communication capability and purchasers' attitudes toward individual communication with the suppliers play important roles in explaining external communication behavior of purchasers. Regarding indirect effects, there are strong total effects of the oral communication capability and the attitudes on the supplier management success as well as satisfaction.Research limitations/implicationsSeveral measures were operationalized using two‐item or three‐item scales. Future research should focus on the development of more comprehensive scales.Practical implicationsVarious conclusions from the results were drawn. Particularly, there are important managerial impacts on supply management and human resource management.Originality/valueThe paper provides the first scientific insight into the relationships between oral communication capability, attitudes toward communication, communication behavior and managerial performance in the field of supply management.
Investigation of compliancy effects on the inviscid instability in fluid flow over a flat plate with heat transfer
Authors: Motsa S.S. , Sibanda P. 
Published: August 2005

PurposeA detailed investigation of the effects of surface flexibility on the inviscid instability of boundary‐layer flow over a horizontal flat plate with heat transfer when the fluid buoyancy is large is undertaken. The aim of this study is to determine whether the inviscid disturbances that arise at this limit are stabilized or destabilized by surface compliancy.Design/methodology/approachFor large positive buoyancy numbers, the motion of the disturbances is governed by the Taylor‐Goldstein (TG) equation. Using the Chebyshev collocation spectral method, the eigen‐solutions of the TG equation are obtained and compared with known results from boundary‐layer flow over rigid flat plates.FindingsThe numerical results show that the effects of surface compliancy are important for small wave numbers and that for the inviscid modes, increasing surface parameters has the effect of destabilizing the flow. For large compliancy parameters the flow structure is indistinguishable from that which obtains in boundary layer flow over rigid surfaces.Research limitations/implicationsThe multiplicity of the compliant wall parameters makes a full parametric study that should show the effect of varying the compliance of the boundary surface on the stability of the flow mathematically intractable. In this study only a brief parametric study, for selected parameters is presented.Originality/valueIt is believed that this paper would be of immense value to applied mathematicians and engineers working in the areas of boundary layer stability and natural convection flows. In the last four decades there has been overwhelming interest shown by researchers in convective boundary‐layer flow. This has largely stemmed from the numerous applications of such flows in geophysics and engineering problems. Many of these applications, for example, polymer and food processing involve the flow of a fluid over a flexible surface. This research aims to bring the dynamics of the surface as a possible mechanism to stabilize convective boundary layer flows and prevent separation.
A local radial point interpolation method for dissipation process of excess pore water pressure
Authors: Wang J.G. , Yan L. , Liu G.R. 
Published: August 2005

PurposeDevelop a local radial point interpolation method (LRPIM) to analyze the dissipation process of excess pore water pressure in porous media and verify its numerical capability.Design/methodology/approachTerzaghi's consolidation theory is used to describe the dissipation process. A local residual form is formulated over only a sub‐domain. This form is spatially discretized by radial point interpolation method (RPIM) with basis of multiquadrics (MQ) and thin‐plate spline (TPS), and temporally discretized by finite difference method. One‐dimensional (1D) and two‐dimensional consolidation problems are numerically analyzed.FindingsThe LRPIM is suitable, efficient and accurate to simulate this dissipation process. The shape parameters, q=1.03, R=0.1 for MQ and η=4.001 for TPS, are still valid.Research limitations/implicationsThe asymmetric system matrix in LRPIM spends more resources in storage and CPU time.Practical implicationsLocal residual form requires no background mesh, thus being a truly meshless method. This provides a fast and practical algorithm for engineering computation.Originality/valueThis paper provides a simple, accurate and fast numerical algorithm for the dissipation process of excess pore water pressure, largely simplifies data preparation, shows that the shape parameters from solid mechanics are also suitable for the dissipation process.
Gendered management in Hungary: perceptions and explanations
Authors: Nagy Beáta 
Published: August 2005

PurposeTo display both the statistical data and the subjective evaluation on the situation of women in management in Hungary.Design/methodology/approachIn the last ten years research activity on gender and work countries have concentrated on the investigation of the sociological issue of the extent to which equal opportunity programmes at the company level have been accomplished in Hungary. The investigations consist of two interrelated parts: questionnaires on women's situation in top management completed by HR departments, and in‐depth interviews with employees. This paper brings together these studies and reports on women's management position at senior levels in Hungarian organisations.FindingsThe results show that, although women's share in the elite pool of economic life increased, women are badly represented in higher managerial positions. Neither employers nor employees find this situation problematic, and continuously emphasised the liberal meaning of equality. There were various ideas about the explanation for the poor representation of women in the company boards, but none of them stressed the organisation as the hindrance of women's advancement.Research limitations/implicationsIt is not based on a representative sample.Originality/valueThere have been minimal investigations on gender issues at companies in Hungary. These results display not only companies' official opinion but also the employees' perceptions on gender inequality. The paper contributes to the neglected area of gender and management research with the Hungarian and Eastern European context.