bluuebunny/crossref_metadata_2025_split huggingface dataset:
Refined second order semi‐analytical design sensitivities
Authors: de Boer H. , van Keulen F. , Vervenne K. 
Published: October 2002

AbstractAccurate and efficient calculation of second order design sensitivities in a finite element context is often difficult. The semi‐analytical (SA) method is efficient and easy to implement but has accuracy problems even for first order shape design sensitivities. To overcome accuracy problems a refined semi‐analytical (RSA) method has been developed for first order sensitivities. The present paper investigates the application of the RSA method to second order design sensitivities. It is found that second order RSA sensitivities are significantly more accurate than their SA counterparts. Copyright © 2002 John Wiley & Sons, Ltd.
Large‐deformation and friction analysis of non‐linear elastic cable networks by second‐order cone programming
Authors: Kanno Y. , Ohsaki M. , Ito J. 
Published: October 2002

AbstractA new formulation is presented for equilibrium shape analysis of cable networks considering geometrical and material non‐linearities. Friction between cables and joint devices is also considered. The second‐order cone programming (SOCP) problem which has the same solution as that of minimization of total potential energy is solved to obtain the equilibrium configuration. The optimality conditions are derived to verify that the solution satisfies equilibrium conditions and friction laws. Since no assumption on stress state is needed in the proposed method, no process of trial and error is involved. No effort is required to develop any analysis software because SOCP can be solved by using the well‐developed software based on the interior‐point method. Copyright © 2002 John Wiley & Sons, Ltd.
Solution of non‐linear boundary integral equations in complex geometries with auxiliary integral subtraction
Authors: Mammoli Andrea A. 
Published: October 2002

AbstractThe boundary integral equation that results from the application of the reciprocity theorem to non‐linear or non‐homogeneous differential equations generally contains a domain integral. While methods exist for the meshless evaluation of these integrals, mesh‐based domain integration is generally more accurate and can be performed more quickly with the application of fast multipole methods. However, polygonalization of complex multiply‐connected geometries can become a costly task, especially in three‐dimensional analyses. In this paper, a method that allows a mesh‐based integration in complex domains, while retaining a simple mesh structure, is described. Although the technique is intended for the numerical solution of more complex differential equations, such as the Navier–Stokes equations, for simplicity the method is applied to the solution of a Poisson equation, in domains of varying complexity. It is shown that the error introduced by the auxiliary domain subtraction method is comparable to the discretization error, while the complexity of the mesh is significantly reduced. The behaviour of the error in the boundary solution observed with the application of the new method is analogous to the behaviour observed with conventional cell‐based domain integration. Copyright © 2002 John Wiley & Sons, Ltd.
How reliable are immunological tools for the detection of ancient proteins in fossil bones?
Authors: Brandt Elisabeth , Wiechmann Ingrid , Grupe Gisela 
Published: October 2002

Abstract100 Pre‐Contact human skeletons from six different excavation sites on the Peruvian coast, which showed an excellent state of preservation both on the macro‐ and the microscopic level, have been investigated for the preservation of three plasma proteins (α2‐HS‐glycoprotein, albumin and α1‐antitrypsin) by enzyme‐linked immunosorbent assay. A subsample of 40 skeletons out of this skeletal series had been analysed for the state of preservation of polymorphic plasma proteins by electrophoretic methods (Brandt et al., 2000), revealing extensive alterations of the target proteins by diagenesis. The question remained, therefore, as to the reliability of common immunological tools for the unambiguous detection and quantification of non‐collagenous proteins in archaeological bone. In this study, we succeeded in the immunological detection of three target proteins in the skeletal remains. However, a variety of non‐specific reactions were also observed with bone extracts from non‐human mammals, some collagen types, and also bacterial cells. This wide range of cross‐reactions with antigens not normally tested in the course of the production of commercially available antibodies adds a cautionary note to immunological approaches towards the study of ancient proteins. Copyright © 2002 John Wiley & Sons, Ltd.
A test of two methods of radiographically deriving long bone cross‐sectional properties compared to direct sectioning of the diaphysis
Authors: Stock Jay T. 
Published: October 2002

AbstractNumerous studies have made use of cross‐sectional geometry to describe the distribution of cortical bone in long bone diaphyses. Several methods can be used to measure or estimate cross‐sectional contours. Direct sectioning (DSM) of the diaphysis is not appropriate in most curatorial contexts, and is commonly substituted with methods based upon bi‐planar radiography: a latex cast method (LCM) or an eccentric elliptical method (EEM). Previous studies have demonstrated that the EEM provides accurate estimates of area measurements, while providing less accurate estimates of second moments of area (Biknevicius & Ruff, 1992; Runestad et al., 1993; Lazenby, 1997). The LCM has been commonly employed, as a way to estimate section contours more accurately, yet the validity of this method has not been adequately documented. This study measures the agreement of these methods against DSM of long bone diaphyses using 21 sections of canine tibiae derived from a study of total hip arthroplasty. The accuracy and agreement of these methods is evaluated using reduced major axis regression, paired sample t‐tests and tests for agreement (Bland & Altman, 1986). The results illustrate that the LCM provides a reasonable estimate of cross‐sectional dimensions, producing cross‐sectional properties that are on average within 5% of properties derived from the DSM. The EEM is found to provide adequate estimates of true cross‐sectional areas, but poor estimates of second moments of area. The use of the LCM is supported for all cross‐sectional properties, but the EEM is only accurate in total area, cortical area and percent cortical area estimates. Copyright © 2002 John Wiley & Sons, Ltd.
Vibration damping materials based on interpenetrating polymer networks of carboxylated nitrile rubber and poly(methyl methacrylate)
Authors: Manoj N. R. , Chandrasekhar L. , Patri M. , Chakraborty B. C. , Deb P. C. 
Published: October 2002

AbstractInterpenetrating polymer networks (IPNs) based on carboxylated nitrile rubber (XNBR) and poly(methyl methacrylate)s were synthesized. Crosslinked XNBR was swollen in methyl methacrylate containing benzoyl peroxide as initiator and tetraethylene glycol dimethacrylate as crosslinking agent. The compositions of the IPNs were varied by changing the swelling time of the rubber in the methacrylate monomer. The dynamic mechanical properties of the IPNs were studied. The dynamic mechanical properties in the range 1–105 Hz were obtained by the time‐temperature superposition of the data under multifrequency mode, which indicated high tan δ with good storage modulus in the entire frequency range. This indicates the suitability of these IPNs as vibration and acoustic dampers. Copyright © 2002 John Wiley & Sons, Ltd.
Telomerase as a prognostic marker in breast cancer: high‐throughput tissue microarray analysis of hTERT and hTR
Authors: Poremba Christopher , Heine Bernhard , Diallo Raihanatou , Heinecke Achim , Wai Daniel , Schaefer Karl‐Ludwig , Braun Yvonne , Schuck Andreas , Lanvers Claudia , Bànkfalvi Àgnes , Kneif Sören , Torhorst Joachim , Zuber Markus , Köchli Ossi R. , Mross Frank , Dieterich Holger , Sauter Guido , Stein Harald , Fogt Franz , Boecker Werner 
Published: October 2002

AbstractTelomerase activity (TA) has been shown to correlate with poor clinical outcome in various tumour entities, indicating that tumours expressing this enzyme may be more aggressive and that TA may be a useful prognostic marker. For breast cancer, however, TA is a controversial prognostic marker; whereas some studies suggest an association between TA and disease outcome, others do not find this association. This study used tissue microarrays (breast carcinoma prognosis arrays) containing 611 samples (each 0.6 mm in diameter) from the tumour centre of paraffin‐embedded breast carcinomas to analyse the catalytic subunit of telomerase, human telomerase reverse‐transcriptase (hTERT), and the internal RNA component (hTR), which are the core components of the telomerase holoenzyme complex. hTERT protein expression was obtained by immunohistochemistry (human anti‐telomerase antibody Ab‐2, Calbiochem), and hTR RNA was measured by radioactive in situ hybridization. hTERT and hTR expression were determined semi‐quantitatively and graded (scores 1–4). Clinical data, such as histological subtype, pT stage, tumour diameter, pN stage, BRE grade, tumour‐specific survival (in months), patient's age and others, were available for statistical analysis. A statistically significant correlation was found between tumour‐specific survival (overall survival) and hTERT expression (p < 0.0001) or hTR expression (p = 0.00110). Tumours with higher scores (scores 3, 4) for hTR and/or hTERT were associated with a worse prognosis. In multivariate analysis, hTERT expression was an independent prognostic factor. Previous studies, focusing on analysis of TA in smaller numbers of fresh‐frozen breast carcinomas by the TRAP assay, gave controversial results with respect to TA as a prognostic marker. Using tissue microarrays from 611 breast carcinomas, this study has demonstrated that increased expression levels of the telomerase core components, hTERT and hTR, are associated with lower overall survival. These findings suggest that TA should be included in future validation studies as a prognostic marker in breast cancer. Copyright © 2002 John Wiley & Sons, Ltd.
Microsatellite analysis of breast carcinoma and corresponding local recurrences
Authors: Regitnig Peter , Moser Renate , Thalhammer Michael , Luschin‐Ebengreuth Gero , Ploner Ferdinand , Papadi Helmtraud , Tsybrovskyy Oleksiy , Lax Sigurd F. 
Published: October 2002

AbstractLocal recurrence is a serious complication of breast carcinoma that reduces quality of life and influences prognosis. The aim of this study was to determine whether local recurrences of breast carcinoma are genetically related to the primary tumours. Forty cases of locally recurrent breast carcinomas (median onset: 3.6 years after primary surgery) were analysed: 22 patients had undergone breast‐conserving therapy and 18 mastectomy. Eighteen microsatellites on chromosomes 2p, 3p, 5q, 10q, 11p, 11q, 13q, 17q, 17p, 18p were amplified by PCR using fluorescent‐labelled primers, automatically detected after polyacrylamide gel electrophoresis and analysed for loss of heterozygosity (LOH) or microsatellite instability (MSI). Follow‐up data were available for 39 cases with a median value of 89 months. All LOH and MSI found in the primary tumours were also present in the corresponding recurrences, indicating that they are genetically related to the primary tumours and not secondary malignancies in the same breast. MSI was found in three cases, of which one harboured MSI at more than two loci. The median value of LOH per case was significantly higher in the recurrent (four per case) compared to the primary tumours (two per case; p < 0.001, Mann–Whitney test), reflecting the genotype of tumour progression. Early local recurrence was associated with specific LOH for TP53.15 (p = 0.018, log‐rank test) in the primary tumours. LOH on D13S1699 or D17S855 was associated with lymph node metastases (p = 0.024 and p = 0.019, respectively; chi‐square test). In addition, tumour grade, lack of oestrogen or progesterone receptor expression, young patient age and early appearance of local recurrence significantly correlated with poor survival. The development of local recurrence despite clear resection margins may result from residual DCIS distant from the invasive carcinoma, homing of circulating tumour cells, or genetically altered, histologically normal breast tissue not immediately adjacent to the invasive carcinoma. Copyright © 2002 John Wiley & Sons, Ltd.
Quantification of CK20 gene and protein expression in colorectal cancer by RT‐PCR and immunohistochemistry reveals inter‐ and intratumour heterogeneity
Authors: Lassmann Silke , Bauer Markus , Soong Richie , Schreglmann Joachim , Tabiti Karim , Nährig Jörg , Rüger Rüdiger , Höfler Heinz , Werner Martin 
Published: October 2002

AbstractCytokeratin 20 (CK20) is an epithelial protein expressed almost exclusively in the gastrointestinal (GI) tract and is widely used as immunohistochemical marker for routine diagnosis. In contrast, CK20 gene expression is not an established marker for the classification of tumours and the detection of disseminated cancer cells in colorectal cancer. Recently, real‐time reverse transcriptase polymerase chain reaction (RT‐PCR) has provided the means for reproducible and quantitative investigation of molecular markers. This report directly compares CK20 mRNA and protein expression in serial sections of archival, formalin‐fixed, paraffin‐embedded (FFPE) colorectal adenocarcinomas. CK20 expression was detected by immunohistochemistry (IHC) in 60/63 (95.2%) cases, by conventional RT‐PCR in 58/60 (96.7%) and by quantitative RT‐PCR using the LightCycler® (LightCycler® is a trademark of a Member of the Roche Group) System in 29/32 (90.6%) microdissected cases, one case yielding variable results. Despite the high detection rate of all three techniques, marked heterogeneity of CK20 expression was seen between different cases and also within individual cases. CK20 expression profiles were not related to particular histopathological features of the tumours. A good correlation (r = 0.8964) was found between CK20 mRNA and protein expression by comparing quantitative RT‐PCR with IHC in 32 cases. This was also true for selected heterogeneous tumour cells within individual cases. Both RT‐PCR and IHC are therefore valuable tools for CK20 detection in colorectal adenocarcinoma, with real‐time RT‐PCR providing supplementary quantitative information. This suggests a promising supportive role for quantitative RT‐PCR in molecular pathology. Copyright © 2002 John Wiley & Sons, Ltd.
E2F1 selects tumour cells for both life and death
Authors: Wyllie Andrew H 
Published: October 2002

AbstractE2F1 is a transcription factor involved in both cell cycle progression and apoptosis. Perhaps surprisingly, these two processes are closely related, and the choice between them appears to be made on the basis of the aggregate of signals flowing into the cell at the time. This may be the means whereby normal cells tune their threshold for apoptosis with respect to the availability of external growth factors, so that cells that are supernumerary to the tissue's needs at the time can be immediately deleted. In many tumours, however, the pathways that link E2F1 activity to apoptosis have been interrupted, sometimes at multiple points. Non‐small‐cell lung carcinoma provides a striking example of this, with the result that expression of E2F1 in these tumours does not correlate with apoptosis but is a good surrogate marker for replicative status. This relationship does not necessarily pertain in other tumour types. Molecules such as E2F1 lie at the core of very significant cell fate decisions, but they are part of a complex matrix of interactions, all of which must be surveyed before interpretation in terms of tumour behaviour is possible. Microarray analysis may provide a way to do this. In the future, however, such interpretations, including predictions of therapeutic response, may be possible through interrogation of the status of a relatively limited number of molecules. Those that preside over critical cellular decision forks (such as the choice between proliferation or death) are good candidates for this role. E2F1 clearly qualifies as one member of this group. Copyright © 2002 John Wiley & Sons, Ltd.
Serious ventricular arrhythmias among users of cisapride and other QT‐prolonging agents in the United States
Authors: Enger Cheryl , Cali Clorinda , Walker Alexander M. 
Published: October 2002

AbstractPurposeTo evaluate the risk of serious ventricular arrhythmia (SVA) with cisapride use in the United States.MethodsThe study population included 28 078 patients under the age of 65 years who received cisapride between 1993 and 1998 with no history of antiarrhythmia treatment. Each follow‐up day was classified according to use of cisapride and other factors. Outcomes of SVAs were identified using medical claims records and National Death Index search, and confirmed by medical record review. Rates of events were calculated for time on and off cisapride. Poisson regression analysis was used to calculate adjusted rate ratios.ResultsThere were 23 cases of SVAs; 10 during periods of cisapride use and 13 during periods of non‐use. The adjusted rate ratio comparing SVA events in cisapride use time to non‐use time was 1.60 (95%CI: 0.67–3.82), and that identified for the other QT‐prolonging drugs was 1.60 (95%CI: 0.65–3.98).ConclusionsThe evidence for an increased risk of SVAs associated with cisapride was equivocal after taking observation time on and off cisapride into account, and adjusting for risk factors, though we cannot exclude the possibility of a 3.8‐fold increased risk. Overall, the plausible risks of cisapride were similar to those of other QT‐prolonging drugs. Copyright © 2002 John Wiley & Sons, Ltd.
Superbasic properties of the SN functional group
Authors: Raczyńska Ewa D. , Woźniak Krzysztof , Dolecka Ewa , Darowska Małgorzata 
Published: October 2002

AbstractQuantum‐chemical calculations (ab initio and semiempirical) were performed for neutral and monoprotonated model compounds of general formula H
iXNH (where X is C, N, S or P and i = 1, 2 or 3) and thermodynamic parameters for the protonation reaction were calculated. All derivatives belong to the family of nitrogen bases. The basicity of H2SNH is larger than that of H2CNH and lower than that of H3PNH, indicating that derivatives with the SN group can form a ‘bridge’ between guanidines and phosphazenes in the gas‐phase superbasicity scale. The basicity of HNNH is lower than that of H2CNH. Topological analysis of electron density distributions in +H3SNH, H2SNH2+ and two neutral isomers of H2SNH showed significant differences in the properties of critical points on N‐ and S‐protonations. All parameters such as ρ, laplacian atomic volumes and dipoles and also bond properties are affected on protonation. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis and polymerization of fluorinated monomers bearing a reactive lateral group. XII. Copolymerization of vinylidene fluoride with 2,3,3‐trifluoroprop‐2‐enol
Authors: Guiot J. , Ameduri B. , Boutevin B. 
Published: October 2002

AbstractAn improved synthesis of 2,3,3‐trifluoroprop‐2‐enol (FA1) and its copolymerization in solution with vinylidene fluoride (VDF, or 1,1‐difluoroethylene) initiated by tert‐butyl peroxypivalate are presented. A new synthesis of FA1, with NaH and lithium diisopropylamine as bases, from 2,2,3,3‐tetrafluoropropanol is described. A series of nine copolymerization reactions were investigated from initial [VDF]0/[FA1]0 molar ratios of 9.1/90.9 to 94.2/5.8. The copolymer compositions were calculated via 19F NMR spectroscopy. From the Tidwell–Mortimer method, the reactivity ratios of both comonomers were determined (rFA1 = 0.11 ± 0.22 and rVDF = 0.83 ± 0.77 at 50°C), and they showed an azeotropic point. Alfrey and Price's Q and e values of FA1 were calculated to be 0.0178 (from QVDF = 0.008), 0.039 (from QVDF = 0.015), and 0.275 (from QVDF = 0.036) and 2.74 (vs eVDF = 1.20), 2.04 (vs eVDF = 0.50), and 1.94 (vs eVDF = 0.4), respectively, and they indicated that FA1 is an electron‐accepting monomer. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3634–3643, 2002
Synthesis and characterization of spirobifluorene‐based polyimides
Authors: Chou Chia‐Hung , Reddy D. Sahadeva , Shu Ching‐Fong 
Published: October 2002

AbstractThe synthesis and properties of organosoluble aromatic polyimides, containing spiro‐skeletal units in the polymer backbone on the basis of the spiro‐diamine monomer, 2,2′‐diamino‐9,9′‐spirobifluorene, are described. In the case of the spiro segment, the two fluorene rings are orthogonally arranged and connected through a tetrahedral bonding carbon atom, the spiro center. As a consequence, the polymer chain is periodically zigzagged with a 90° angle at each spiro center. This structural feature minimizes interchain interactions and restricts the close packing of the polymer chains, resulting in amorphous polyimides that have good solubility in organic solvents. Compared with their fluorene‐based cardo analogues, the spirobifluorene‐based polyimides have an improved solubility. Furthermore, the main‐chain rigidity of the polyimide appears to be preserved because of the presence of the spiro structure, which restricts the free segmental mobility. As a result, these polyimides exhibit a high glass‐transition temperature (Tg's) and good thermal stability. The Tg's of these polyimides were in the range of 287–374 °C, and the decomposition temperatures in nitrogen for a 10% weight loss occurred at temperatures above 570 °C. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3615–3621, 2002
Synthesis of polyphosphonates containing pendant chloromethyl groups by the polyaddition of bis(oxetane)s with phosphonic dichlorides
Authors: Minegishi Shouji , Tsuchida Shinji , Sasaki Masaki , Kameyama Atsushi , Kudo Hiroto , Nishikubo Tadatomi 
Published: October 2002

AbstractThe polyaddition of 4,4′‐bis[(3‐ethyl‐3‐oxetanyl)methoxy]biphenyl (4,4′‐BEOBP) and phenylphosphonic dichloride (PPDC) with quaternary onium salts as catalysts proceeded under mild reaction conditions to afford a polymer containing phosphorous atoms in its main chain. A polyphosphonate with a high number‐average molecular weight (10,300) was obtained by the reaction of 4,4′‐BEOBP and PPDC in the presence of tetraphenylphosphonium chloride (TPPC) in o‐dichlorobenzene at 130 °C for 24 h. The structure of the resulting polymer was confirmed with IR, 1H NMR, and 31P NMR spectroscopy. Furthermore, it was proved that the polyaddition of certain bis(oxetane)s with phosphonic dichlorides proceeded smoothly to give corresponding polyphosphonates with TPPC as the catalyst. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3835–3846, 2002
Proton‐conducting polymers based on benzimidazoles and sulfonated benzimidazoles
Authors: Asensio Juan Antonio , Borrós Salvador , Gómez‐Romero Pedro 
Published: October 2002

AbstractA sulfonated derivative of polybenzimidazole is reported, and its properties are analyzed in comparison with related polybenzimidazole proton‐conducting materials. Poly(2,5‐benzimidazole), poly(m‐phenylenebenzobisimidazole), and poly[m‐(5‐sulfo)‐phenylenebenzobisimidazole] were prepared by condensation of the corresponding monomers in polyphosphoric acid. Several adducts of these polymers with phosphoric acid were prepared. The resulting materials were characterized by chemical analysis, Fourier transform infrared spectroscopy, and thermogravimetric analysis; also, the dc conductivity of doped and undoped derivatives was measured. Similar to what has been observed for the commercial polybenzimidazole polymer (also examined here for comparison), the title polymers exhibit high thermal stability. Furthermore, their doping with phosphoric acid leads to a significant increase in conductivity from less than 10−11 Scm−1 for the undoped polymers to 10−4 Scm−1 (both at room temperature) for their acid‐loaded derivatives. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3703–3710, 2002