bluuebunny/crossref_metadata_2025_split huggingface dataset:
Association of ampullary and colorectal malignancies
Authors: Das Ananya , Neugut Alfred I. , Cooper Gregory S. , Chak Amitabh 
Published: January 2004

AbstractBACKGROUNDBecause of the similarities in terms of carcinogenesis and natural history between cancer of the ampulla of Vater and colorectal cancer, the authors examined whether ampullary and colorectal malignancies occur in the same individuals at increased rates.METHODSWe used data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute for the period from January 1973 through December 1999. Person‐years of follow‐up for patients with ampullary (or colorectal) cancer were used to calculate the expected number of cases of colorectal (or ampullary) cancer as a second primary malignancy. Standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) were calculated using Byar limits and assuming a Poisson distribution.RESULTSThe authors identified 2043 white patients with ampullary cancer who were included in the SEER registry between 1973 and 1999. Over an aggregate 5674 person‐years of follow‐up, 30 patients, compared with an expected 14, developed colorectal cancer, yielding an overall SIR of 2.14 (95% CI, 1.45–3.06). Similarly, 57 of 262,066 white patients with colorectal cancer developed ampullary cancer over an aggregate 1,270,255 person‐years of follow‐up, yielding an SIR of 2.18 (95% CI, 1.69–2.85).CONCLUSIONSPatients with ampullary cancer are at increased risk for a second primary colorectal malignancy, and patients with colorectal cancer are at increased risk for a second primary ampullary malignancy. These findings suggest that ampullary and colorectal malignancies share common environmental and/or genetic risk factors. Cancer 2004. © 2003 American Cancer Society.
Gamma radiation sensitivity and risk of malignant and benign salivary gland tumors
Authors: Zheng Rong , Wang Li‐E , Bondy Melissa L. , Wei Qingyi , Sturgis Erich M. 
Published: January 2004

AbstractBACKGROUNDThe salivary gland is a highly radiosensitive organ. Exposure to gamma radiation is a risk factor for both malignant (MSTs) and benign salivary gland tumors (BSTs), but the exact mechanisms remain unknown. The objectives of the current study were to determine whether gamma radiation–induced chromatid breaks increase the risk of MSTs and BSTs and whether there is any difference in risk between these two diseases.METHODSThe authors performed a pilot case–control study of 57 patients with salivary gland diseases (45 patients with MSTs and 12 patients with BSTs) and 105 cancer‐free controls. Peripheral blood lymphocytes from these participants were cultured and exposed to gamma radiation (1.5 grays). Five hours later, metaphase spread slides were evaluated. The chromatid breaks in 50 well‐spread metaphase slides were counted to determine the average number of chromatid breaks per cell (b/c).RESULTSMultivariate logistic regression analyses revealed that gamma radiation–induced b/c values greater than the median of the controls were a significant risk factor for salivary gland tumors (adjusted odds ratio [OR], 17.25; 95% confidence interval [CI], 4.92–60.49). The risk remained significant for MSTs (adjusted OR, 40.45; 95% CI, 5.27–310.17) but was of borderline significance for BSTs (adjusted OR, 4.73; 95% CI, 0.94–23.87) when these tumors were analyzed separately.CONCLUSIONSIn the current study, high levels of chromatid breaks in lymphocytes induced by gamma irradiation were associated with an independent risk for MSTs and were likely to increase the risk of BSTs. However, larger studies are needed to verify these findings. Cancer 2004. © 2003 American Cancer Society.
Temozolomide in the treatment of recurrent malignant glioma
Authors: Chang Susan M. , Theodosopoulos Philip , Lamborn Kathleen , Malec Mary , Rabbitt Jane , Page Margaretta , Prados Michael D. 
Published: January 2004

AbstractBACKGROUNDOptions for chemotherapy at the time of recurrence in patients with malignant glioma are limited. The authors describe the efficacy and safety results of their institution's open‐label, compassionate‐use protocol of temozolomide for patients with recurrent malignant glioma.METHODSPatients with recurrent malignant glioma at any time during recurrence were treated with oral temozolomide at a dose pf 150 mg/m2 per day on a 5‐day schedule every 28 days. If this dose was tolerated, then escalation to 200 mg/m2 was allowed. Clinical evaluations and assessments of tumor response were performed every 2 months. All patients or their surrogates signed approved Institutional Review Board consent forms.RESULTSAmong 213 patients who were treated, 33% had Grade 3 tumors, and 67% had Grade 4 tumors. The overall objective response rate was 16% in both of these patient groups; and an additional 51% and 30% of patients with Grade 3 and Grade 4 tumors, respectively, had stable disease as their best response. The 6‐month progression‐free survival rates were 41% and 18% for patients with Grade 3 and Grade 4 tumors, respectively. The median survival was 49 weeks for patients with Grade 3 tumors and 32 weeks for patients with Grade 4 tumors. The major toxicity was hematologic toxicity. In multivariate analysis, the Karnofsky performance score was a significant predictor of survival for patients with Grade 4 tumors.CONCLUSIONSTemozolomide was well tolerated in patients with recurrent malignant glioma and had modest efficacy, even at the time of multiple recurrences. Cancer 2004. © 2003 American Cancer Society.
Activity of interferon‐α and isotretinoin in patients with advanced, refractory lymphoid malignancies
Authors: Tsimberidou Apostolia‐Maria , Giles Francis , Romaguera Jorge , Duvic Madeleine , Kurzrock Razelle 
Published: January 2004

AbstractBACKGROUNDInterferon‐α (IFN‐α) and retinoids have shown nonoverlapping toxicity and each has shown antitumor activity in patients with lymphoma. The aim of the current study was to assess the toxicity, safety, and efficacy of IFN‐α combined with isotretinoin in patients with advanced, refractory lymphoid malignancies.METHODSAdults with biopsy‐proven advanced lymphoid malignancy were treated. Patients with compromised bone marrow function (platelet counts as low as 30 × 109/L) were eligible. Treatment was comprised of IFN‐α at a starting daily dose of 3 mega units subcutaneously and isotretinoin orally starting at a dose of 1 mg/kg daily in 2 divided doses.RESULTSForty‐four patients were evaluable. Their median age was 57 years (range, 18–82 years). Eighteen patients had advanced cutaneous T‐cell lymphoma, 6 patients had peripheral T‐cell lymphoma, 14 patients had Hodgkin disease, and 6 patients had a variety of other lymphoid malignancies. Patients with Hodgkin disease had received a median of 6 previous therapies (range, 3–12 therapies) and patients with other lymphoid malignancies had received a median of 4 previous therapies (range, 1–9 therapies). The median duration of treatment was 4 months (range, 0.25–38 months). The overall response rate was 38.6% (complete response in 5 patients [11.3%] and partial response in 12 patients [27.3%]). The median response duration was 3 months (range, 1–95+ months). The most common toxicities were low‐grade fever, flu‐like symptoms, and fatigue (IFN‐α effects); dry mouth and skin and hypertriglyceridemia (cis‐retinoic acid effects); and thrombocytopenia (which generally occurred in patients with low baseline platelet counts).CONCLUSIONSIFN‐α and isotretinoin combination therapy had antitumor activity and was well tolerated in heavily pretreated patients with lymphoid malignancies. Cancer 2004. © 2003 American Cancer Society.
Parallel proximal‐point algorithms for mixed finite element models of flow in the subsurface
Authors: Alduncin Gonzalo , Vera‐Guzmán Norberto 
Published: January 2004

AbstractParallel proximal‐point algorithms for mixed finite element models of flow in the subsurface are presented. The applied methodology corresponds to operator splitting and non‐overlapping domain decomposition methods, combined with resolvent or proximation characterizations and proximal‐point algorithms. In this manner, macro‐hybrid mixed finite element models are systematically derived, in general being globally non‐conforming on the basis of non‐matching grids. Also, iterative algorithms of the Uzawa penalty–duality type are produced, which are well‐conditioned and robust. These parallel iterative algorithms generalize optimization and augmented Lagrangian procedures, and can be interpreted as implicit and semi‐implicit numerical time marching schemes. Copyright © 2004 John Wiley & Sons, Ltd.
Third‐order methods for first‐order hyperbolic partial differential equations
Authors: Cheema T. A. , Taj M. S. A. , Twizell E. H. 
Published: January 2004

AbstractIn this paper numerical methods for solving first‐order hyperbolic partial differential equations are developed. These methods are developed by approximating the first‐order spatial derivative by third‐order finite‐difference approximations and a matrix exponential function by a third‐order rational approximation having distinct real poles. Then parallel algorithms are developed and tested on a sequential computer for an advection equation with constant coefficient and a non‐linear problem. Copyright © 2003 John Wiley & Sons, Ltd.
Treatment of Neumann boundaries in the complex variable boundary element method
Authors: Sato Kozo , Watanabe Yusuke 
Published: January 2004

AbstractFor potential flow, the complex variable boundary element method (CVBEM) is formulated in terms of the velocity potential Φ and the stream function Ψ. In actual flow problems, Φ and ∂Φ/∂n are given along Dirichlet and Neumann boundaries, respectively. In the CVBEM, the Neumann‐type condition ∂Φ/∂n is not directly handled, and, instead, Ψ is used to define Neumann boundaries. Owing to this discrepancy, numerical difficulties are raised along Neumann boundaries. The current study addresses two such difficulties: (1) multiple Neumann boundaries and (2) branch cuts across Neumann boundaries. The first problem is due to the fact that Ψ along multiple boundaries cannot be specified a priori, and the second problem is due to the discontinuous jump inherent in Ψ for sink/source singularities. To overcome these difficulties, a new formulation of the CVBEM to solve for the unknown Ψ values and a proper way of branch‐cut placement are proposed, and these techniques are verified against example problems. Copyright © 2004 John Wiley & Sons, Ltd.
Multi‐level fracture network model for coupled seepage and stress fields in rock mass
Authors: Junrui Chai , Shouyi Li , Yanqing Wu 
Published: January 2004

AbstractIt is one of the issues of subsurface water resource research to investigate the models for coupled seepage and stress fields in rock mass. The present models can be summarized as the three types of (equivalent) continuum model, the fracture network model and the double media model. In this paper, a new multi‐level fracture network model is proposed for coupled seepage and stress fields in rock mass. According to the scale and permeability, the ruptures, faults, fractures, joints and pores in rock mass are divided into four levels, i.e. the level‐1 real fracture network, the level‐2 random fracture network, the level‐3 equivalent continuum system and the level‐4 continuum system. The level‐1 real fracture network is composed of larger ruptures and faults, whose distribution, mechanical and hydro‐mechanical parameters can be determined from the real geological information. Based on the fractures measurement and statistics, the level‐2 random fracture network is simulated by means of Monte—Carlo technique. The level‐3 equivalent continuum system is established to reflect the overall behaviour of small joints by means of the theory of hydraulic conductivity tensor. The level‐4 continuum system is composed of pores in rock, whose behaviour can be represented by the homogeneous and isotropic parameters. These fracture networks of four levels are related to each other by water and energy balance. In fracture network of each level, the different interaction between seepage and stress is introduced to construct the multi‐level fracture network model for coupled seepage and stress fields in rock mass. An engineering example is also given to show the applicability of the proposed model. Copyright © 2004 John Wiley & Sons, Ltd.
Eigensolutions for factorable matrices of special patterns
Authors: Kaveh A. , Sayarinejad M. A. 
Published: January 2004

AbstractThe method developed for eigensolution for matrices of special structures in Kaveh and Sayarinejad (Commun. Numer. Meth. Engng 2003; 19: 125–136) is extended to a more general special form known as Form III. Efficient methods are presented for evaluating the eigenvalues and eigenvectors of these matrices. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical analysis of boundary‐value problems for singularly perturbed differential‐difference equations: small shifts of mixed type with rapid oscillations
Authors: Kadalbajoo M. K. , Sharma K. K. 
Published: January 2004

AbstractWe study the boundary‐value problems for singularly perturbed differential‐difference equations with small shifts. Similar boundary‐value problems are associated with expected first‐exit time problems of the membrane potential in models for activity of neurons (SIAM J. Appl. Math. 1994; 54: 249–283; 1982; 42: 502–531; 1985; 45: 687–734) and in variational problems in control theory. In this paper, we present a numerical method to solve boundary‐value problems for a singularly perturbed differential‐difference equation of mixed type, i.e. which contains both type of terms having negative shifts as well as positive shifts, and consider the case in which the solution of the problem exhibits rapid oscillations. The stability and convergence analysis of the method is given. The effect of small shift on the oscillatory solution is shown by considering the numerical experiments. The numerical results for several test examples demonstrate the efficiency of the method. Copyright © 2004 John Wiley & Sons, Ltd.
Strip layer method for simulation of the three‐dimensional deformations of plate and strip rolling
Authors: Hong‐Min Liu , Dan Jin , Ying‐Rui Wang 
Published: January 2004

AbstractA new method—the strip layer method (SLM) is used to simulate the three‐dimensional deformations of plate and strip rolling process. The rolling deformation zone is divided evenly into a number of layers along the altitudinal direction of plate or strip, every layer plate (strip) is divided into a number of streamline strip elements along metal flow traces, and the streamline strip elements are mapped onto the corresponding rectangle strip elements for analysis and computation. The longitudinal distribution model of the metal lateral displacement is constructed to be a quartic curve, its lateral distribution is expressed as the third‐power spline function, and its altitudinal distribution is fitted to be a parabolic curve. Based on the flow theory of plastic mechanics, the three‐dimensional deformations and stresses of the deformation zone are analysed and formulated. Compared with the streamline strip element method (SSEM), the strip layer method considers the uneven distributions of stresses and deformations along altitudinal direction, and realizes an accurate analysis and computation. The simulation examples indicate that the method and the model of this paper are in accord with facts, and provide a new reliable engineering‐computation method for a three‐dimensional mechanics simulation of plate and strip rolling process. Copyright © 2004 John Wiley & Sons, Ltd.
A parametric study on the natural frequencies of unidirectional composite conical springs
Authors: Yıldırım Vebil 
Published: January 2004

AbstractThis paper deals with the combined influences of the vibrational parameters chosen as the material types, number of active turns, helix pitch angle, minimum to maximum radii of the cylinder and maximum cylinder to wire diameters on the first six resonance frequencies of unidirectional composite conical helical springs with solid circle section and fixed–fixed ends. The transfer matrix method based on the distributed parameter model is used for the determination of the fundamental natural frequencies. The rotary inertia, the shear and axial deformation effects are taken into account in the solution based on the first‐order shear deformation theory. Variation of the natural frequencies with the chosen vibrational parameters is given in non‐dimensional graphical forms. Using these charts, a numerical prediction of the first six linear dimensional free vibration frequencies of composite conical springs and their upper and lower limits with respect to the geometrical and material properties of the spring can be made with a good approximation. Copyright © 2004 John Wiley & Sons, Ltd.
Stationary biharmonic maps from Rm into a Riemannian manifold
Authors: Wang Changyou 
Published: January 2004

AbstractFor m ≥ 5, we prove that a stationary extrinsic (or intrinsic, respectively) biharmonic map u ∈ W2,2(Ω, N) from Ω ⊂ Rm into a Riemnanian manifold N is smooth away from a closed set of (m − 4)‐dimensional Hausdorff measure zero. © 2003 Wiley Periodicals, Inc.
Adiabatic charge pumping in open quantum systems
Authors: Avron Joseph E. , Elgart Alexander , Graf Gian Michele , Sadun Lorenzo , Schnee Kai 
Published: January 2004

AbstractWe introduce a mathematical setup for charge transport in quantum pumps connected to a number of external leads. It is proved that under rather general assumption on the Hamiltonian describing the system, in the adiabatic limit, the current through the pump is given by a formula of Büttiker, Prêtre, and Thomas, relating it to the frozen S‐matrix and its time derivative. © 2004 Wiley Periodicals, Inc.
Polyhedral stability ‐ on the growth of flat crystal faces on small molecule and protein crystals
Authors: Nanev Chr. N. 
Published: January 2004

AbstractThe old standing problem of face morphology is discussed. A special emphasis is put on the macroscopically flat faces, appearing on small molecule crystals mostly during calm growth, under low supersaturations. As distinct, protein crystals are growing with macroscopically flat faces even under surprisingly high supersaturations. Explanations of these facts are suggested by considering the surface micro‐profile of crystal faces which growth is driven by screw dislocations. It is shown that, due to kinetic reasons, the tips of the growth hillocks and the valley between them have to be levelled to some extent (at least on a quasi‐atomic scale) under low enough supersaturations. The amplitude of the surface roughness has to be suppressed also due to the surface energy gain, especially under quasi‐equilibrium. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The effect of alloying elements on the crystallization behaviour and on the properties of galvanized coatings
Authors: Vourlias G. , Pistofidis N. , Stergioudis G. , Tsipas D. 
Published: January 2004

AbstractThe influence of the alloying elements on the interface reactions of zinc coatings during the galvanization process was examined. These reactions affect the crystallization and the structure and properties of the outer layer of the coatings. Depending on the type and concentration of the alloying additions in the galvanizing bath differences were induced in the crystallization process of the Fe‐Zn phases. It was found that both the concentration and the distribution of the alloying elements played an important role in the growth of the phases. The formation of the phases and the distribution of the alloying elements in the coatings were determined using X‐Ray diffraction (XRD) and Scanning Electron Microscopy (SEM) associated with an Energy Dispersive X‐Ray Spectroscopy (EDS) analysis. Finally the behaviour of the galvanized coatings was examined under accelerated salt spray corrosion conditions. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The relations of sintering conditions and microstructures of [Bi0.5(Na1‐x‐yKxLiy)0.5]TiO3 piezoelectric ceramics
Authors: Lin D. M. , Xiao D. Q. , Zhu J. G. , Yu P. , Yan H. J. , Li L. Z. , Zhang W. 
Published: January 2004

AbstractBismuth sodium titanate (abbreviated as BNT) based solid solution, [Bi0.5(Na1‐x‐yKxLiy)0.5]TiO3 (0 < x + y < 1) ceramics, was invented in our group. These ceramics, which are considered as new candidates for lead‐free piezoelectric materials, were prepared by conventional ceramic sintering technique. The results of X‐ray diffraction show that the ceramics possess a single perovskite phase. The relations of the sintering conditions and the microstructures of the ceramics were studied. It was found that the optimized sintering condition is at 1100‐1150 °C for 2‐3 h, the grains of the ceramics have very regular shape, and the grain size of the ceramics is in the range of 1.3‐2.2 μm. These ceramics with the compositions of high amount of K+ and low amount of Li+ have relatively large piezoelectric charge constant (d33), and can be put into practical applications. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Minerals successions crystallisation related to tunisian natural brines
Authors: M'nif A. , Rokbani R. 
Published: January 2004

AbstractNatural brines sampled from Sebkhats in southern part of Tunisia are considered to be seawater‐type solutions. The equilibrium solubility of this kind of solutions might be described by the fivefold seawatertype system Na+, K+, Mg2+, Cl‐, SO42‐ // H2O. The crystallisation sequences of salts, observed under solar evaporation, of two different Tunisians brines is discussed. Very important differences between the foreseeable results, based on the Equilibrium Solubility Diagram at 25 °C, and the experimental ones are settled. An attempt to explain the differences, based on the so‐called “solar sequences” as well as the “solar diagram” of evaporation, is made. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetoresistance, voltage‐current characteristics, and Hall effect measurements of bulk MgB2 superconductors
Authors: Kayed T. S. 
Published: January 2004

AbstractBulk MgB2 samples were prepared from the commercially available powder (Alfa‐Aesar). One of the samples was used in measuring the transport properties by the DC four‐probe technique while the other was used in measuring Hall effect using the van‐der‐Pauw configuration. From the transport measurements, we noticed that the R‐T curves shift to lower temperatures under applied magnetic field without any observed enlargement of the transition width. Tc gradually decreases from 37 K at zero field to 32 K at B = 1.4 T. Our V‐I data were found to obey a power law expression V ∝ Iβ(T, B). The change of β with temperature and magnetic field was shown and discussed. RH is positive under positive applied magnetic field. The 1/ RH linear dependency on T, usually observed in high temperature superconductors, could not be observed in our case. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)