bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the classical shell model underlying bilinear degenerated shell finite elements
Authors: Malinen Mika 
Published: August 2002

AbstractWe study the shell models arising in the numerical modelling of shells by bilinear degenerated shell finite elements. The numerical model of a cylindrical shell obtained by using flat shell elements is given an equivalent formulation based on a classical two‐dimensional shell model. We use the connection between the models to explain how a parametric error amplification difficulty or locking is avoided by some elements. Copyright © 2001 John Wiley & Sons, Ltd.
A Galerkin/least‐squares finite element formulation for consolidation
Authors: Truty A. 
Published: August 2002

AbstractA Galerkin/least‐squares (GLS) finite element formulation for problem of consolidation of fully saturated two‐phase media is presented. The elimination of spurious pressure oscillations appearing at the early stage of consolidation for standard Galerkin finite elements with equal interpolation order for both displacements and pressures is the goal of the approach. It will be shown that the least‐squares term, based exclusively on the residuum of the fluid flow continuity equation, added to the standard Galerkin formulation enhances its stability and can fully eliminate pressure oscillations. A reasonably simple framework designed for derivation of one‐dimensional as well as multi‐dimensional estimates of the stabilization factor is proposed and then verified. The formulation is validated on one‐dimensional and then on two‐dimensional, linear and non‐linear test problems. The effect of the fluid incompressibility as well as compressibility will be taken into account and investigated. Copyright © 2001 John Wiley & Sons Ltd.
Efficient computation of order and mode of corner singularities in 3D‐elasticity
Authors: Dimitrov A. , Andrä H. , Schnack E. 
Published: August 2002

AbstractA general numerical procedure is presented for the efficient computation of corner singularities, which appear in the case of non‐smooth domains in three‐dimensional linear elasticity. For obtaining the order and mode of singularity, a neighbourhood of the singular point is considered with only local boundary conditions. The weak formulation of the problem is approximated by a Galerkin–Petrov finite element method. A quadratic eigenvalue problem (P+λQ+λ2R) u=0 is obtained, with explicitly analytically defined matrices P,Q,R. Moreover, the three matrices are found to have optimal structure, so that P,R are symmetric and Q is skew symmetric, which can serve as an advantage in the following solution process. On this foundation a powerful iterative solution technique based on the Arnoldi method is submitted. For not too large systems this technique needs only one direct factorization of the banded matrix P for finding all eigenvalues in the interval ℛe(λ)∈(−0.5,1.0) (no eigenpairs can be ‘lost’) as well as the corresponding eigenvectors, which is a great improvement in comparison with the normally used determinant method. For large systems a variant of the algorithm with an incomplete factorization of P is implemented to avoid the appearance of too much fill‐in. To illustrate the effectiveness of the present method several new numerical results are presented. In general, they show the dependence of the singular exponent on different geometrical parameters and the material properties. Copyright © 2001 John Wiley & Sons, Ltd.
Hypersingular boundary integral equation for axisymmetric elasticity
Authors: de Lacerda L. A. , Wrobel L. C. 
Published: August 2002

AbstractAn axisymmetric hypersingular boundary integral formulation for elasticity problems is presented in this paper. The hypersingular and strong‐singular fundamental solutions are derived and their singular behaviour is discussed in detail for different locations of the source point. Several free terms arise from the limiting process when generating hypersingular boundary integral equations, including an extra one specific to the axisymmetric formulation which does not appear in two and three dimensional cases. The singularity subtraction technique is used to regularize all strong‐singular and hypersingular integrals, and their evaluation procedure is explained. Finally, the developed formulation is assessed through simple numerical tests. Copyright © 2001 John Wiley & Sons, Ltd.
Archaeological analysis of shell middens in the Beagle Channel, Tierra del Fuego Island
Authors: Estevez Jordi , Piana Ernesto , Schiavini Adrian , Juan‐Muns Nuria 
Published: August 2002

AbstractAn archaeological programme beginning in 1993, in the Beagle Channel, aims to describe the long‐term record of maritime faunal exploitation, and relate it to the environmental record. Results from quantitative analysis of remains from a series of shell midden excavations indicate a remarkably stable and resilient marine biota over the last 6500 years. Only in the previous century have there been changes in fauna, which might correspond to recent global warming. Copyright © 2001 John Wiley & Sons, Ltd.
Viking age horse graves from Kaunas region (Middle Lithuania)
Authors: Bertašius M. , Daugnora L. 
Published: August 2002

AbstractBalts' territories have one peculiarity—large amounts of horse bones are found in burial grounds. This phenomenon is typical to the Prussians (5th–11th centuries) and Lithuanians (Kaunas region 8th–11th centuries)Horse burials of the 8th–11th centuries reflect the archaeological culture of Middle Lithuania most significantly.Several horse burial types have been defined on the basis of individuals; osteological signs and the archaeological data of the horse remains. A typical horse grave is when the whole horse was buried. Sometimes only a head or a head with forelegs, or scattered horse remains are found in a burial. The large number of burial grounds with an abundance of horse graves testifies to a very expressive ritual of horse offering in the Balts' region.On the basis of the data obtained, we determined that mostly 4–10 year old horses were buried in the grounds of Middle Lithuania.From the bone measurements, it has been determined that the length of metacarpals ranges between 180 and 216 mm (the average length 193.1±0.99 mm); the length of metatarsals between 218 and 253 mm (average length 233.9±0.73 mm).These data demonstrate that horses of different types were buried in Marvelė and Veršvai burial grounds (wither height 120–136 cm). A certain number of the larger horses (wither height 136–144 and 153 cm; length of metacarpals 210–222 mm) might not have belonged to local breeds.We have come to the conclusion that the most similar horse skeletons (according to the osteometric data) were found in Latvia. Copyright © 2001 John Wiley & Sons, Ltd.
Performance appraisal in the Maldives public service: challenges and issues
Authors: Asim Mohamed 
Published: August 2002

AbstractA structured method of evaluating and rewarding the performance of employees in the Maldives public service did not exist before 1996. Personnel decisions, such as employee promotions, were subjective and based merely on the recommendation of the heads of departments. Hence, in 1996, the Government of Maldives introduced a performance appraisal system, based on rewarding employees through the assessment of several factors such as quality of work, job knowledge and performance. The reward came in the form of annual salary increments. In reviewing this system, the article finds that human resource units or divisions within departments now need to be strengthened for the effective implementation of the system; more training has to be provided to public service employees in terms of raising their awareness as to the objectives of the performance appraisal exercise; and the performance appraisal framework needs to be more flexible in differentiating very high performers, at the same time devising a strategy for the improvement of employees who slack in performance. Copyright © 2001 John Wiley & Sons, Ltd.
Preparation and characterization of polyaniline blends with polyvinyl acetate, polystyrene and polyvinyl chloride for toxic gas sensors
Authors: Hosseini S. Hossein , Entezami Ali A. 
Published: August 2002

AbstractThe conditions of processing and gas sensing of ­polyaniline (PANi) blends with polyvinyl acetate (PVAc), polystyrene (PS) and polyvinyl chloride (PVC) were investigated. Flexible, free‐standing and stretchable films of various blends compositions were obtained by casting. The mechanisms of the conducting blends response to a selection of gases and vapours were investigated using two techniques: measurement of conductance and mass changes using a four‐point probe method and X‐ray fluorescence (XRF) device, respectively. These responses to toxic gases and vapours are better explained by polymer blends than homopolymers. Prepared films were exposed to hydrogen halides, hydrogen cyanide, halogens, monochloroacetic acid (MCAA), 1‐3‐5 trichloromethyl benzene (TCMB), methylbenzyl bromide (MBB), bromoacetone (BA) and cyanogen bromide (CB). The changes in conductivity of various polymer frequently observed are partly due to one stage in the two‐stage sorption perhaps involving the swelling of the polymer and then diffusion of gases into polymer chains. The swelling of polymers is a slow process, therefore, we have pre‐swelled polymer films which tend to decrease the response times of blends in respect to gases. The structures of the blends are examined by STA (TGA & DSC) and SEM studies. Copyright © 2001 John Wiley & Sons, Ltd.
Improving cell affinity of ­poly(D,L‐lactide) film modified by anhydrous ammonia plasma treatment
Authors: Yang Jian , Bei Jianzhong , Wang Shenguo 
Published: August 2002

AbstractAnhydrous ammonia gaseous plasma treatment was used for improving cell affinity of the poly(D,L‐lactide) film surface. The contact angle was measured and the surface energy was calculated through harmonic mean equations. The surface chemical composition of the sample was identified by X‐ray photoelectron spectroscopy (XPS) analysis. It was demonstrated that the O‐containing and N‐containing groups such as hydroxyl and amine were incorporated onto the surface of films. The effect of preserving methods for maintaining the hydrophilicity was also investigated. The result indicated that preserving at low temperature (0–4 °C) was sufficient to maintain the improvements. It could resolve the problem of hydrophilicity being partially lost with preserving time after plasma treatment. Mouse 3T3 fibroblast cells were used as model cells to compare the cell affinity of the modified films and control. The ammonia plasma treatment could promote the cells attachment and cells growth. After 4 days culture, the plasma treated films yielded almost two magnitude cells compared with the control. Copyright © 2002 John Wiley & Sons, Ltd.
Integrin up‐regulation in chronic liver disease: relationship with inflammation and fibrosis in chronic hepatitis C
Authors: Nejjari Mimoun , Couvelard Anne , Mosnier Jean‐François , Moreau Alain , Feldmann Gérard , Degott Claude , Marcellin Patrick , Scoazec Jean‐Yves 
Published: August 2002

AbstractIn 94 patients with chronic hepatitis C, the pattern of integrin expression was correlated with firstly, the histological activity index, necro‐inflammatory grade, and stage of fibrosis; secondly, the expression of inflammatory markers including ICAM‐1; and thirdly, the extent and intensity of laminin deposition in the perisinusoidal matrix. Immunohistochemical results were evaluated according to a semi‐quantitative scoring system or by image analysis. Increased β1 expression was observed in 88.2% of cases. The expression of α1 and α5 was increased in 55% and 58.5% of cases, respectively. α6 chain was detected in 78.7% of cases. There were no statistically significant differences in integrin expression level according to Knodell's score, inflammatory grade, or stage of fibrosis. ICAM‐1 expression was higher in patients with high scores for β1 expression, but the differences were not statistically significant. There were significantly more patients with high scores for β1 expression among those with continuous perisinusoidal deposition of laminin. Moreover, a close statistical correlation was observed between α6 induction and perisinusoidal laminin deposition (p<0.001). The results suggest that integrin up‐regulation in chronic hepatitis C is more closely related to the fibrotic process than to the inflammatory lesions. This reinforces the idea that integrin induction in chronic liver disease is part of a coordinated process involved in the progression of liver fibrosis. Copyright © 2001 John Wiley & Sons, Ltd.
‘Diabetic holiday foot syndrome’: a preventable complication†
Authors: Stanaway S.E.R.S. , Gill G.V. , Kaczmarcyk Edward , Kaye Linda 
Published: August 2002

AbstractFoot ulceration in diabetic patients is a serious complication, with the potentially devastating possibility of lower limb amputation. We describe six patients with type 2 diabetes who all developed significant neuropathic foot ulceration during holidays, mostly in hot countries abroad. All were male, aged 52–62, and one patient developed three ulcers on the same foot on three consecutive holidays, the last one resulting in a below knee amputation. The specific causes of ulceration were often related to walking barefoot (on sand, shingle or hot flagstones), or wearing inadvisable beach footwear. The association of poor educational compliance and a high‐risk environment may lead to this specific ‘diabetic holiday foot syndrome’. Intensive warning education prior to at‐risk patients going on holiday may help prevent this serious complication. Copyright © 2001 John Wiley & Sons, Ltd.
Adverse drug events in hospitalized patients treated with cardiovascular drugs and anticoagulants
Authors: Zaidenstein R. , Eyal S. , Efrati S. , Akivison L. , Koren Michowitz M. , Nagornov V. , Golik A. 
Published: August 2002

AbstractPurposeTo evaluate the incidence of serious adverse drug events (ADEs) caused by cardiovascular drugs during hospitalization in a department of internal medicine, and to identify patients at highest risk.Patients and methodsAll the patients treated with cardiovascular drugs and/or anticoagulants in the department between November 1999 and January 2000 were recruited into the study. During hospitalization the patients' charts were reviewed by a pharmacist and a clinician, and the occurrence of serious ADEs was assessed using the Naranjo algorithm. ‘Possible’ and ‘doubtful’ ADEs were not counted.ResultsOf 496 patients who were enrolled in the study, 20 (4%) had serious ADEs. Compared to patients without ADEs, patients in the ADE group were older (72 ± 12.6 years (mean ± SD) vs. 65 ± 13 years, p = 0.048), their average stay in hospital was longer (7.3 ± 5.5 days vs. 5.2 ± 3.7 days, p = 0.018) and their mean urea levels were higher (10.8 ± 9.3 mmol/l vs. 7.8 ± 5.3 mmol/l, p = 0.027). The most frequent background pathologies of the 20 patients with ADEs were hypertension (in 18 (90%)) and atrial fibrillation (in nine (45%)). In 50% of the the ADE group there was a history of drug allergies. The ADEs recorded were bleeding in four (20%), arrhythmias in six (30%), orthostatic hypotension in six (30%) and skin necrosis, paranoid reaction, acute hepatitis and acute renal failure in four (20%). The causative drugs were warfarin (which accounted for 25% of the ADEs), beta‐blockers (15%), propafenone (5%), amiodarone (5%), and Ca2+‐channel blockers, nitrates and diuretics (together accounting for 50% of ADEs). Drug combinations were implicated in 50% of ADE.ConclusionsSerious ADEs were developed by 4% of hospitalized patients taking cardiovascular drugs. Those at highest risk were older, were receiving multiple drug therapy and had higher urea levels. Warfarin and beta‐blockers were the drugs causing the largest number of adverse effects . ADEs are an important cause of preventable morbidity, often with serious economic implications and special attention should be given to their prevention. Copyright © 2002 John Wiley & Sons, Ltd.
Controlled release of aminophylline from poly (N‐isopropylacrylamide‐co‐itaconic acid) hydrogels
Authors: Katime Issa , Valderruten Nora , Quintana José R 
Published: August 2002

AbstractN‐Isopropylacrylamide (NIPA) has been copolymerized with itaconic acid (IA) in the presence of N,N‐methylenebisacrylamide (BIS) as crosslinker. The swelling capacity and the release rate of aminophylline at 37 °C are reported. Maximum equilibrium swelling increases as the itaconic acid content in the hydrogel increases. The experimental data suggest clearly that the swelling process obeys second‐order kinetics. According to this, the kinetic constant, k, and the maximum equilibrium swelling, W∞, have been calculated. Drug release from fully swollen hydrogels follows Fick's law closely, but deviates from it for xerogels.© 2001 Society of Chemical Industry
Dye‐affinity hollow‐fibres and their lysozyme adsorption–desorption characteristics
Authors: Şenel Serap , Akgöl Sinan , Arica Yakup , Denizli Adil 
Published: August 2002

AbstractDye‐affinity adsorption is increasingly used for protein separation. Hollow‐fibres have advantages as adsorbents in comparison to conventional bead supports because they are not compressible and can eliminate internal diffusion limitations. The aim of this study was to explore in detail the performance of polyamide hollow‐fibres to which Reactive Green HE‐4BD was attached for adsorption of lysozyme. The hollow‐fibre was characterized by scanning electron microscopy. These dye‐carrying hollow‐fibres (26.3 µmol g−1) were used in the lysozyme adsorption–elution studies. The effect of initial concentration of lysozyme and medium pH on the adsorption efficiency of dye‐attached hollow‐fibres was studied in a batch system. The non‐specific adsorption of lysozyme on the polyamide hollow‐fibres was 1.8 mg g−1. Reactive Green HE‐4BD attachment significantly increased the lysozyme adsorption up to 41.1 mg g−1. Langmuir adsorption model was found to be applicable in interpreting lead adsorption by Reactive Green HE‐4BD attached hollow fibres. Significant amount of the adsorbed lysozyme (up to 95%) was eluted in 1 h in the elution medium containing 1.0 M NaSCN at pH 8.0. In order to determine the effects of adsorption conditions on possible conformational changes of lysozyme structure, fluorescence spectrophotometry was employed. We concluded that polyamide dye‐affinity hollow‐fibres can be applied for lysozyme adsorption without causing any significant conformational changes. Repeated adsorption–elution processes showed that these dye‐attached hollow‐fibres are suitable for lysozyme adsorption.© 2001 Society of Chemical Industry
Synthesis, characterization and crosslinking of functional star‐shaped poly(ε‐caprolactone)
Authors: Turunen Markus P K , Korhonen Harri , Tuominen Jukka , Seppälä Jukka V 
Published: August 2002

AbstractStar‐shaped low molecular weight poly(ε‐caprolactone)s (PCLs) were synthesized and functionalized with crosslinkable terminal groups for subsequent crosslinking. The ε‐caprolactone (CL) prepolymers were polymerized by ring‐opening in the presence of polyglycerine (PGL) as an initiator (1, 3 and 5 mol%) and Sn(II)2‐ethylhexanoate as a catalyst. Characterization of the prepolymer by 13C/1H nuclear magnetic resonance (NMR) spectroscopy, size exclusion chromatography (SEC), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) revealed a six‐armed star‐shaped structure for the prepolymer with the molecular weight controlled by the ratio of PGL and CL. Functionalization of the hydroxyl‐terminated prepolymer was carried out with maleic or itaconic anhydride. In both cases, the characterization of the functionalized prepolymer showed that the hydroxyl groups were completely substituted. The functionalized PCLs were successfully crosslinked through the reaction of double bonds. The crosslinking was induced either thermally with organic peroxide or photochemically with a photosensitive initiator. Characterization of the crosslinked PCLs by Soxhlet extraction, DSC and FTIR showed that the itaconic double bond was much more reactive in thermal crosslinking than the maleic double bond. Thus, the crosslinked prepolymers that were functionalized with itaconic double bonds achieved a gel content of about 90%. A gel content of 100% was achieved with several compositions where crosslinking agents were employed.© 2002 Society of Chemical Industry
New poly(arylene ether)s with pendant phosphonic acid groups
Authors: Miyatake Kenji , Hay Allan S. 
Published: August 2002

AbstractSoluble brominated poly(arylene ether)s containing mono‐ or dibromotetraphenylphenylene ether and octafluorobiphenylene units were synthesized. The polymers were high molecular weight (weight‐average molecular weight = 115,100–191,300; number‐average molecular weight = 32,300–34,000) and had high glass‐transition temperatures (>279 °C) and decomposition temperatures (>472 °C). The brominated polymers were phosphonated with diethylphosphite by a palladium‐catalyzed reaction. Quantitative phosphonation was possible when 50 mol % of a catalyst based on bromine was used. The diethylphosphonated polymers were dealkylated by a reaction with bromotrimethylsilane in carbon tetrachloride followed by hydrolysis with hydrochloric acid. The polymers with pendant phosphonic acid groups were soluble in polar solvents such as dimethyl sulfoxide and gave flexible and tough films via casting from solution. The polymers were hygroscopic and swelled in water. They did not decompose at temperatures of up to 260 °C under a nitrogen atmosphere. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3770–3779, 2001
Stability of photocurable anhydrides: Methacrylic acid mixed anhydrides of nontoxic diacids
Authors: Tarcha Peter J. , Su Lin , Baker Tom , Langridge Denton , Shastri Venkatram , Langer Robert 
Published: August 2002

AbstractDisproportionation of the liquid mixed anhydride dimethacrylic sebacic anhydride (m‐SA) to methacrylic anhydride and polyanhydride oligomers, as well as vinylic polymerization, can occur on workup and storage at room temperature. Dimethacrylic 1,3‐bis(p‐carboxyphenoxy) propane, being a solid, can also disproportionate, but the propensity to do so is lower than for m‐SA. These events can be suppressed with free‐radical inhibitors, and the inhibitor 2+3‐t‐butyl‐4‐methoxyphenol is a more effective stabilizer than 4‐methoxyphenol at 20 °C. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4189–4195, 2001
Synthesis and characterization of novel aliphatic polycarbonates
Authors: Wang Xu‐Li , Zhuo Ren‐Xi , Liu Li‐Jian , He Feng , Liu Gang 
Published: August 2002

AbstractA new six‐membered cyclic carbonate monomer, 5‐benzyloxy‐trimethylene carbonate, was synthesized from 2‐benzyloxy‐1,3‐propanediol, and the corresponding polycarbonate, poly(5‐benzyloxy‐trimethylene carbonate) (PBTMC), was further synthesized by ring‐opening polymerization in bulk at 150 °C using aluminum isobutoxide [Al(OiBu)3], aluminum isopropoxide, or stannous octanoate as an initiator. The results showed that a higher molecular weight polycarbonate could be obtained in the case of Al(OiBu)3. The protecting benzyl group was removed subsequently by catalytic hydrogenation to give a polycarbonate containing a pendant hydroxyl group (PHTMC). The polycarbonates obtained were characterized by Fourier transform infrared spectroscopy, 1H NMR,13C NMR, gel permeation chromatography, and DSC. NMR results of PBTMC offered no evidence for decarboxylation occurring during the propagation. The pendant hydroxyl group in PHTMC resulted in an enhancement of the hydrophilicity of the polycarbonate. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 70–75, 2002