bluuebunny/crossref_metadata_2025_split huggingface dataset:
A modified method of characteristics incorporating streamline diffusion
Authors: Allen Myron B. , Liu Biyue 
Published: August 2005

AbstractA hybrid finite‐element method, combining ideas from a modified method of characteristics and the streamline diffusion method, delivers accurate solutions to the advection–diffusion equation. An error analysis for the case of tensorial diffusion shows that the lowest‐order version of the scheme, which allows one to use a symmetric linear solvers at each time step, possesses first‐order accuracy in time and space. Numerical experiments demonstrate the scheme's ability to model advection‐dominated transport of solute plumes without distorting sharp fronts. © 1995 John Wiley & Sons, Inc.
Truncation error in grid generation: A case study
Authors: Knupp P. , Luczak R. 
Published: August 2005

AbstractTheoretical proofs state that the planar Winslow or homogenous Thompson–Thames–Mastin (hTTM) map is a diffeomorphism, yet numerical solutions to the hTTM equations produce folded grids on the so‐called “horseshoe” domain. A quasi‐analytic solution to the horseshoe problem is constructed to demonstrate that folding is due to truncation error effects. Higher‐order difference methods are also explored. © 1995 John Wiley & Sons, Inc.
A computer science approach for solving elliptic differential equations
Authors: Peralta R. , Chen B. 
Published: August 2005

AbstractA method that combines computer science and numerical analysis techniques for the solution of elliptic partial differential equations in domains consisting of the union of rectangles is presented. It is applied to Laplace's equation and to the Navier–Stokes equations in several domains. The method is very flexible and can be easily modified to solve other equations. © 1995 John Wiley & Sons, Inc.
Monotone method and convergence acceleration for finite‐difference solutions of parabolic problems with time delays
Authors: Lu Xin 
Published: August 2005

AbstractIn this article we study a finite‐difference system, which is a discrete version of a class of nonlinear reaction‐diffusion systems with time delays. Existence‐comparison and uniqueness theorem are first established for the discretized problem by the method of upper and lower solutions. A monotone iterative scheme is also developed for the solution of the finite‐difference system. Under a convergence acceleration scheme, it is shown that the monotone sequences converge quadratically to the solution of the finite‐difference system. At last, numerical results on some model problems are demonstrated to substantiate our theorems. © 1995 John Wiley & Sons, Inc.
An operator‐splitting algorithm for the three‐dimensional diffusion equation
Authors: Khan Liaqat Ali , Liu Philip L.‐F. 
Published: August 2005

AbstractA second‐order‐accurate and unconditionally stable operator‐splitting algorithm for the three‐dimensional diffusion equation is presented in this article. The governing equation is split into three one‐dimensional equations, and the split equations are solved by a finite‐element method. The simulation characteristics of the algorithm are demonstrated by numerical experiments. © 1995 John Wiley & Sons, Inc.
AKT activation predicts outcome in breast cancer patients treated with tamoxifen
Authors: Kirkegaard Tove , Witton Caroline J , McGlynn Liane M , Tovey Sian M , Dunne Barbara , Lyon Alison , Bartlett John MS 
Published: August 2005

AbstractOestrogen receptor (ERα) expression is a strong predictor of response to endocrine therapy. The PI3K/AKT/mTOR signal transduction pathway has been implicated in endocrine resistance in vitro. The present study was carried out to test the hypothesis that AKT activation mediates tamoxifen resistance in clinical breast cancer. Immunohistochemistry (IHC) using AKT1‐3, pan‐AKT, pAKT (Thr‐308), pAKT (Ser‐473), pER (Ser‐167), and pHER2 antibodies was performed on 402 ERα‐positive breast carcinomas from patients treated with tamoxifen. High pAKT (Ser‐473) activity (p = 0.0406) and low AKT2 expression (p = 0.0115) alone, or in combination [high pAKT (Ser‐473)/low AKT2; ‘high‐risk’ patient group] (p = 0.0014), predicted decreased overall survival in tamoxifen‐treated patients with ERα‐positive breast cancers. There was no significant association between tumour levels of AKT expression or activity and disease‐free survival (DFS); however, the ‘high‐risk’ patient group was significantly more likely to relapse (p = 0.0491). During tamoxifen treatment, neither AKT2 nor pAKT predicted DFS. Finally, activation of AKT, via phosphorylation, was linked to activation of both HER2 and ERα in this patient cohort. The data presented here show that the PI3K/AKT/mTOR pathway is associated with relapse and death in ERα‐positive breast cancer patients treated with tamoxifen, supporting in vitro evidence that AKT mediates tamoxifen resistance. Patients with a ‘high‐risk’ expression profile were at increased risk of death (hazard ratio 3.22, p = 0.002) relative to ‘low‐risk’ patients, highlighting the potential that tumour profiling, with multiple IHC markers predictive of therapeutic response, may improve patient selection for endocrine therapies, eg tamoxifen or aromatase inhibitor‐based treatments. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The concept of the ‘percent wasted patients’ in preventive health strategies
Authors: Cardinal Héloise , Monfared Amir Abbas Tahami , Dorais Marc , LeLorier Jacques 
Published: August 2005

AbstractPurposeTo better communicate the impact of poor persistence when preventive therapies are initiated, we propose a new measure that is intuitively understandable for clinicians. This measure is the percent wasted patients (PWP).MethodsThe PWP is the percentage of patients, out of the new users of a given preventive treatment, who have discontinued therapy before the time point at which clinical benefits become apparent on the cumulative incidence curves in randomized controlled trials (RCTs) comparing active treatment to placebo. To calculate the PWP, the RCTs that demonstrated the efficacy of the therapy under study must be identified from a MEDLINE search. The point at which the cumulative incidence curves for the main outcome in the experimental and placebo group start diverging is identified and is called the point of visual divergence (PVD). Then, using pharmaceutical claims databases, the percent persistence at the PVD in new users of the therapy is determined. The PWP is then calculated as 100% persistence at PVD.ResultsFor primary prevention with statins, in the province of Quebec, the PWP is 44%. Of 100 patients starting statins for the primary prevention of coronary events, 44 will represent a waste in health resources because they will have discontinued therapy before any clinical benefit can be expected.ConclusionsThe PWP is a simple measure that can be used by clinicians to select the therapies that need the most reinforcement concerning the importance of persistence. Copyright © 2005 John Wiley & Sons, Ltd.
Fluorescence polarization measurements of orientation in labeled polyisoprene networks
Authors: Jarry J. P. , Monnerie L. 
Published: August 2005

AbstractFluorescence polarization was used to measure segmental orientation in stretched polyisoprene networks. Stress and orientation of chemically bonded fluorescent labels were simultaneously recorded during stretching. Two deviations from the classical theory of rubber elasticity were observed: (i) an extra orientation of dry networks, which was interpreted by assuming the existence of weak nematiclike interactions between segments, and (ii) a saturation of orientation at high elongation which could be due to local conformational changes.
Hydrodynamic studies on model branched polystyrenes
Authors: Roovers J. , Toporowski P. M. 
Published: August 2005

AbstractThe measurement of the sedimentation velocity coefficient of narrow distribution linear, four‐arm and six‐arm star and comb polystyrenes in a theta solvent permits the experimental determination of h, i.e., the ratio of the translational friction coefficients of the branched polymer to that of its linear homolog. A comparison of experimental h/g1/2 values with theoretical predictions can then be made. It was observed that the equivalent hydrodynamic radii derived from sedimentation and intrinsic viscosity measurements are identical within experimental error.
Order in poly(N‐(10‐n‐alkyloxycarbonyl‐n‐decyl)‐maleimides)
Authors: De La Campa J. I. Gonzalez , Barrales‐Rienda J. M. 
Published: August 2005

AbstractWide‐angle and small‐angle x‐ray diffraction patterns of 11 poly(N‐(10‐n‐alkyloxycarbonyl‐n‐decyl)maleimides) (PEMI) (including only even members of the series) have been obtained on unoriented samples. They show major maxima at two diffraction angles. The one at the larger angles is due to the interaction of neighboring n‐alkyl side‐chains. The smaller one (which shows second and third orders of diffraction in higher members of the series, n = 14 to n = 22, where n is the number of methylene groups in the external n‐alkyl sequence in the side chain) is related to the distance between lamellar planes formed by the main chains. In all cases, the measured layer separation di is higher than the structural unit length L of the side‐chain in the most extended conformation, and lower than the length corresponding to two side‐chains. On the basis of the experimental results reported here, a model is proposed for the packing of these comblike polymers in the solid state. The mode of packing is also supported by infrared spectra in the 720 cm−1 region for the CH2 rocking mode of vibration of the n‐alkyl side‐chain.
A fourier‐transform infrared spectroscopic study of the hydrolytic stability of silane coupling agents on E‐glass fibers
Authors: Ishida Hatsuo , Koenig Jack L. 
Published: August 2005

AbstractFourier‐transform (FT) infrared spectroscopy has been applied to the study the hydrothermal degradation of various coupling agents on E‐glass fibers. The coupling agents studied include γ‐methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, and cyclohexyltrimethoxysilane. The amount of coupling agents on E‐fibers was measured as a function of immersion time in water at 80°C. Structural changes were also followed by obtaining FT‐IR difference spectra of the coupling agent on the glass fiber surface. Silanes desorb quite differently depending on the organofunctional groups. The resistance to desorption is strongly influenced by the organization of the silane interphase as well as the solubility of the silane in water.
The occurrence of head‐to‐head butene units in ethylene‐butene copolymers and corresponding ethyl branches in low‐density (branched) polyethylenes
Authors: Dechter James J. , Mandelkern Leo 
Published: August 2005

AbstractA high resolution carbon‐13 NMR study of an ethylene‐butene copolymer has yielded a spectrum whose resonances could be assigned to isolated ethyl branches, 1,3‐diethyl branching as well as 1,2‐diethyl branches resulting from head‐to‐head butene polymerization. All these structures are present in the same sample. An examination of all the published spectra of low‐density (branched) polyethylenes has revealed many examples of heretofore unassigned resonances which can be associated with this latter type of diethyl branching in these polymers. Spin‐lattice relaxation times have been determined, when feasible, for the carbon atoms in each of the three branched structures.
Radical polymerizations of 4‐pentamethyldisilylstyrenes
Authors: Saigo Kazuhide 
Published: August 2005

AbstractRadical polymerization of 4‐pentamethyldisilylstyrene (1) and 4‐pentamethyldisilyl‐α‐methylstyrene (2) have been conducted. Monomer reactivity ratious (r1 and r2) of 1 and 2 with styrene (M1) were measured with Fineman‐Ross plots. The resonance factor (Q) and polar factor (e) of a Q–e scheme for 1 were conculated with the r1 and r2 values. The inductive effect (σI) resonance effect (σ) of the pentamethyldisily group were monitored with the 1H‐ and 13C‐NMR spectra of 1. The magnitudes of σI and σ were found to be analogous to those of the trimethylsilyl group, indicating that the disilyl group shows a net electron‐withdrawal effect
Cationic polymerization of α‐methylstyrene in dichloromethane initiated with system 2,5‐dichloro‐2,5‐dimethylhexane‐BCl3. I. Molecular weight distribution and stereoregularity of poly (α‐methylstyrene)
Authors: Toman L. , Pokorný S. , Spěváček J. 
Published: August 2005

AbstractIn the polymerization of α‐methylstyrene (α‐MeSt) in dichloromethane in the temperature interval between −60 and −20°C the polymer yield decreased with increasing temperature depending on the initiating system used (I‐IV) in the series II > I > IV > III, where I was a freshly prepared solution of 2,5‐dichloro‐2,5‐dimethylhexane (DDH) with BCl3 in dichloromethane, was the same solution as in the preceding case, but stored at room temperature one month and then used, III was a freshly prepared BCl3 solution in dichloromethane, and IV was the initiation system “H2O”/BCl3. The polymer samples synthesized at ≤ −30°C had a bimodal molecular weight distribution (MWD), which was attributed to the different participation of ionic pairs and free ions in the propagation reaction. The stereoregularity of the polymer observed (ca. 85% syndiotactic and ca. 15% heterotactic triads) determined from the 1H‐NMR spectra was not affected by the difference in the initiation system. MWD of the polymer samples was investigated by the GPC method
Peak area measurements of cross‐polarization magic‐angle‐spinning 13C‐NMR spectra of crosslinked polystyrenes
Authors: Ford Warren T. , Periyasamy M. , Mohanraj S. , McEnroe Frajk J. 
Published: August 2005

AbstractCross‐polarization magic‐angle‐spinning 13C‐NMR spectra of polystyrenes crosslinked with 1–20% of methine vinyl carbon 13C‐labeled p‐divinylbenzene and of Friedel–Crafts crosslinked poly(chloromethylstyrene)s have been obtained with both glossy solid and CDCl3‐swollen gel samples. The spectra of natural abundance, uncrosslinked, glassy polystyrene, and the spectra of the solid labeled networks give aliphatic and aromatic peak areas only 0.7 times as large per 13C atom as that of poly(oxymethylene). Similarly the crosslinked poly(chloromethylstyrene) gave peak areas about 0.6 times that of internal poly(oxymethylene). The labeled gels give peak areas 0.2–0.6 times as large per 13C atom as glassy polystyrene, and the peak areas in spectra of gels increase with the divinylbenzene content
Synthesis and properties of polyketones containing thiophene links
Authors: Yi Mi Hie , Choi Kil‐Yeong , Jung Jin Chul 
Published: August 2005

AbstractA series of polyketones containing thiophene links was synthesized by the Friedel‐Crafts polymerization of these dithienylalkanes with aromatic diacid chlorides or dicarbonyl chlorides comprising thiophene links with diphenyl compounds. The resulting polymers had inherent viscosities in the range of 0.11–0.27 dL/g and showed poor solubilities to common organic solvents except strong acids. These thiophene‐based polyketones exhibited fairly good thermal stabilities. The TGA data revealed 5% weight losses at 375–450°C and residual weights at 500°C were 43–79% under nitorgen. It was found that the thermal stabilities of these polymers were superior to those of polymides or polysulfonamides containing thiophene links and almost comparable to common aromatic polyketones
Aqueous polymerization of methyl methacrylate initiated by Ce(IV)–alcohol redox systems: Effect of acid concentration and additives
Authors: Fernandez M. D. , Guzman G. M. 
Published: August 2005

AbstractPolymerization of methyl methacrylate (MMA) initiated by ceric ammonium nitrate in combination with alcohols, isopropyl and, isobutyl alcohol, has been studied in aqueous nitric acid. The effect of nitric acid and nitrate ion concentrations on the initial rate of polymerization as well as on that of ceric ion consumption and on polymer molecular weight has been investigated. The rate of polymerization initially rapidly to a maximum with increasing nitric acid concentration at constant nitrate ion concentration, and then, decreased at higher acid concentrations. The rate of ceric ion consumption increased on increasing the acid concentration. A fall in both the rates was observed as the nitrate ion concentration increased, and when acid concentration was kept constant. Average‐molecular weights decreased with increasing the acid concentration; whereas they increased with increasing that of nitrate ion. The effect of certain water‐miscible organic solvents has also been studied. Both the rates increased in their presence, whereas the molecular weight underwent a decrease
Detection of Lymph Node Micrometastases and Isolated Tumor Cells in Sentinel and Nonsentinel Lymph Nodes of Colon Cancer Patients
Authors: Bembenek Andreas , Schneider Ulrike , Gretschel Stephan , Fischer Joerg , Schlag Peter M. 
Published: August 2005

AbstractAbout 20% to 30% of colon cancer patients classified as node negative by routine hematoxylin‐eosin (H&E) staining are found to have micrometastases (MM) or isolated tumor cells (ITC) in sentinel lymph nodes (SLNs) if analyzed by step sections and immunohistochemistry (IHC). Whether SLNs are in this respect representative for all lymph nodes was addressed in this study. SLNs were identified using the intraoperative blue dye detection technique. If all lymph nodes (SLNs and non‐SLNs) of a patient were negative by routine H&E staining, they were step‐sectioned and analyzed by IHC using pancytokeratin antibodies. We identified at least one SLN in 47 of the 55 patients (85%) and examined a median of 26 lymph nodes per patient (range 10–59). By routine H&E staining, 14 of the 47 patients showed lymph node metastases (30%); the remaining 33 were classified as node‐negative. In this group (33 patients), 1011 lymph nodes were analyzed by step sections and IHC: 14 of 70 SLNs. (20%) but only 37 of 941 non‐SLNs (4%) had MM/ITC (p < 0.001). Furthermore, 13 of the 33 H&E‐negative patients were found to have MM/ITC (39%). In 11 of the 13 patients, MM/ITC were identified in both SLNs and non‐SLNs in 1 patient in the SLN only, and in 1 patient in a non‐SLN only (sensitivity for the identification of MM/ITC: 92%; negative predictive value: 95%). The SLN biopsy is a valid tool to detect, as well as exclude, the presence of MM/ITC in colon cancer patients. Our results may be of prognostic relevance and influence patient stratification for adjuvant therapy trials.
Normotensive Pheochromocytoma: Institutional Experience
Authors: Agarwal Amit , Gupta Sushil , Mishra Anand Kumar , Singh Nikhil , Mishra Saroj K. 
Published: August 2005

AbstractWe report an audit of nine cases of subclinical or normotensive pheochromocytoma managed in our department. This is the first report from India of such a series. During the period 1990–2003 a total of 45 patients of pheochromocytoma were diagnosed and managed in the Department of Endocrine Surgery, Sanjay Gandhi Postgraduate Institute of Medical Sciences. Among them, nine patients were diagnosed as having subclinical or normotensive pheochromocytoma. Inclusion criteria for normotensive pheochromocytoma were: no previous history of hypertension clinically and, in the previous treatment documents, any episode of symptoms suggesting high blood pressure. The demographic profile, clinical presentation, biochemical investigations, imaging results, surgical notes, and follow‐up record were reviewed retrospectively. All patients had a primary complaint of flank/abdominal pain and were normotensive. Seven had elevated urinary metanephrine levels, and one patient had normal values. One patient did not undergo the urinary metanephrine assay. Imaging of the abdomen showed seven adrenal and two extra‐adrenal masses (eight had computed tomography scans of the abdomen, and one underwent ultrasonography). After selective α‐adrenergic blockade (prazosin), surgery was performed. Six patients required infusion of sodium nitroprusside intraoperatively. The final histopathology was pheochromocytoma in all patients. Metanephrine levels were normal during the follow‐up. Normotensive pheochromocytomas are a distinct entity, and all adrenal incidentalomas should be investigated for catecholamine hypersecretion. We support the use of preoperative α‐adrenergic blockade, and these patients should be treated along the same lines as hypertensive pheochromocytoma.
Acute versus chronic pain treatment in Alzheimer's disease
Authors: Pickering Gisèle , Jourdan Didier , Dubray Claude 
Published: August 2005

AbstractSeveral studies have suggested a lower consumption of analgesics in patients with Alzheimer's disease (AD) than in cognitively intact individuals (ND), but little attention has been paid to a distinction in analgesic consumption between acute and chronic pain treatment. The aim of this prospective and longitudinal study is a comparison in AD and ND residents at selection, and one year later, of analgesic consumption for acute and chronic pain, with an assessment of cognitive status (with the Mini Mental State Examination (MMSE)). Three hundred institution residents (150 AD and 150 ND), 20% male and 80% female (84.4 − 8.3 years old), were included in this study. Analgesic consumption and MMSE were reassessed at one year's distance (period 1 P1 and 2 (P2)). Analgesic consumption for acute pain was not significantly different for AD and ND at selection time or one year later, while MMSE declined significantly for AD (6 − 7 (P1) versus 4 − 6 (P2) p < 0.01, and ND individuals 23 − 5 (P1) versus 20 − 6 (P2), p < 0.01, respectively). Chronic pain analgesic consumption however was significantly lower in AD than in ND (p < 0.01). These findings may suggest a dissociation between sensory‐discriminative (lateral pain system) and motivational‐affective (medial pain system) aspects of pain in individuals with AD. This dissociation must be further investigated as it may have important consequences for pain evaluation and pain treatment in this vulnerable population.