bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical stability of unsteady stream‐function vorticity calculations
Authors: Sousa E. , Sobey I. J. 
Published: June 2003

AbstractThe stability of a numerical solution of the Navier–Stokes equations is usually approached by con‐ sidering the numerical stability of a discretized advection–diffusion equation for either a velocity component, or in the case of two‐dimensional flow, the vorticity. Stability restrictions for discretized advection–diffusion equations are a very serious constraint, particularly when a mesh is refined in an explicit scheme, so an accurate understanding of the numerical stability of a discretization procedure is often of equal or greater practical importance than concerns with accuracy. The stream‐function vorticity formulation provides two equations, one an advection–diffusion equation for vorticity and the other a Poisson equation between the vorticity and the stream‐function. These two equations are usually not coupled when considering numerical stability. The relation between the stream‐function and the vorticity is linear and so has, in principle, an exact inverse. This allows an algebraic method to link the interior and the boundary vorticity into a single iteration scheme. In this work, we derive a global time‐iteration matrix for the combined system. When applied to a model problem, this matrix formulation shows differences between the numerical stability of the full system equations and that of the discretized advection–diffusion equation alone. It also gives an indication of how the wall vorticity discretization affects stability. Despite the added algebraic complexity, it is straightforward to use MATLAB to carry out all the matrix operations. Copyright © 2003 John Wiley & Sons, Ltd.
A three dimensional surface‐to‐surface projection algorithm for non‐coincident domains
Authors: Heinstein M. W. , Laursen T. A. 
Published: June 2003

AbstractA numerical procedure is outlined to achieve the least squares projection of a finite dimensional representation from one surface to another in three dimensions. Although the applications of such an algorithm are many, the specific problem considered is the mortar tying of dissimilarly meshed grids in large deformation solid mechanics. The algorithm includes a nearest neighbour search, a systematic subdivision of the surface of intersection into smooth subdomains (termed segments), and a robust numerical quadrature scheme for evaluation of the spatial integrals defining the mortar projection. The procedure outlined, while discussed for the mesh tying problem, is directly applicable to the study of contact‐impact. Published in 2003 by John Wiley & Sons, Ltd.
Solving singularly perturbed Riccati equation with Mathematica
Authors: Mikhailov M. D. 
Published: June 2003

AbstractAn exponentially fitted finite‐difference scheme of order one for singularly perturbed Riccati equation has been presented and tested on three problems in this journal (Selvakumar K. Commun. Numer. Meth. Engng 1997; 13: 1–12). This note demonstrates the superiority of Mathematica in solving the same problems. Copyright © 2003 John Wiley & Sons, Ltd
Evaluating convective heat transfer coefficients from a given set of data by using Mathematica
Authors: Mikhailov M. D. 
Published: June 2003

AbstractMathematica software system is used to solve the problem considered by Jambunathan et al. (Int. J. Heat Mass Transfer 1996; 39: 2329–2332), where a neural network is applied to predict heat transfer coefficients from a given set of experimentally obtained data. Copyright © 2003 John Wiley & Sons, Ltd.
On the behaviour of the ANM continuation in the presence of bifurcations
Authors: Baguet S. , Cochelin B. 
Published: June 2003

AbstractThe asymptotic‐numerical method (ANM) is a path following technique which is based on high order power series expansions. In this paper, we analyse its behaviour when it is applied to the continuation of a branch with bifurcation points. We show that when the starting point of the continuation is near a bifurcation, the radius of convergence of the power series is exactly the distance from the starting point to the bifurcation. This leads to an accumulation of small steps around the bifurcation point. This phenomenon is related to the presence of inevitable imperfections in the FE models. We also explain that, depending on the maximal tolerated residual error (out‐of‐balance error), the ANM continuation may continue to follow the fundamental path or it may turn onto the bifurcated path without applying any branch switching technique. Copyright © 2003 John Wiley & Sons, Ltd.
Integration algorithms for planar anisotropic shells with isotropic and kinematic hardening at finite strains
Authors: Han Chung‐Souk , Lee Myoung‐Gyu , Chung Kwansoo , Wagoner R. H. 
Published: June 2003

AbstractAn elasto‐plastic formulation at finite strains was considered with isotropic and kinematic hardening and anisotropic yield functions. In order to find a simple but thermomechanically consistent continuum mechanical basis for stress integration algorithms of shell problems, evolution equations of the plastic strain rate and internal variables were derived. This was performed in the stress‐free intermediate configuration with the Mandel stress and corresponding back stress tensors. The resulting relations were then transformed into the current configuration and restricted to small elastic strains. For an algorithmic treatment of this material formulation for shell problems, the kinematic hardening was reformulated in stress‐related terms to obtain a set of equations for planar anisotropic elasto‐plastic materials. Finally, an updated iterative treatment for the elasto‐plastic shell at finite strains was derived utilizing the cutting plane algorithm. Copyright © 2003 John Wiley & Sons, Ltd.
On the optimization of a Gabor filter‐based feature extractor for handwritten character recognition
Authors: Uchimura Shunji , Watanabe Masanori , Hamamoto Yoshihiko 
Published: June 2003

AbstractIn order to use the Gabor feature extraction system in the real world, the problem of optimizing the Gabor parameters must be resolved. In the conventional optimization method, several candidates are prepared, the error rate for them is found through experimentation, and the parameters which give the lowest recognition error rates are taken to be optimal values. However, in the conventional method, setting the candidate values so that they are certain to include optimal values is a common problem. In this paper, the authors evaluate from the standpoint of the optimalness of the solutions and computational burden the optimization methods (two‐stage conventional method, response surface method, and energy function method) that address the problems of the conventional method. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 86(12): 27–37, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10140
Chemical composition of the essential oils of Astrodaucus orientalis (L.) Drude leaves and seeds
Authors: Mirza M. , Baher Nik Z. , Dini M. 
Published: June 2003

AbstractThe essential oils of Astrodaucus orientalis (L.) Drude leaves and seeds growing wild in Iran were examined by GC and GC–MS. The composition of the seed oil sample was compared with that of the leaf oil. Twenty‐six compounds were identiﬁed in both the leaf and the seed oil. Although the composition of the seed oil was similar to that of the leaf oil, quantitative differences in concentration of some constituents were observed. The major components of the leaf oil were fenchyl acetate (44.5%) and α‐pinene (21.6%) but the major constituents of the seed oil were myrcene (47.7%) and β‐pinene (21.8%). The seed oil was found to contain lower amounts of bornyl acetate, germacrene D and δ‐cadinene than the leaf oil. Copyright © 2003 John Wiley & Sons, Ltd.
Learning networks in health and Parkinson's disease: Reproducibility and treatment effects
Authors: Carbon Maren , Ghilardi Maria Felice , Feigin Andrew , Fukuda Masafumi , Silvestri Giulia , Mentis Marc J. , Ghez Claude , Moeller James R. , Eidelberg David 
Published: June 2003

AbstractIn a previous H215O/PET study of motor sequence learning, we used principal components analysis (PCA) of region of interest (ROI) data to identify performance‐related activation patterns in normal subjects and patients with Parkinson's disease (PD). In the present study, we determined whether these patterns predicted learning performance in subsequent normal and untreated PD cohorts. Using a voxel‐based PCA approach, we correlated the changes in network activity that occurred during antiparkinsonian treatment and their relationship to learning performance. We found that the previously identified ROI‐based patterns correlated with learning performance in the prospective normal (P< 0.01) and untreated PD (P< 0.05) cohorts. Voxel analysis revealed that target retrieval was related to a network characterized by bilateral activation of the dorsolateral prefrontal, premotor and anterior cingulate cortex, the precuneus, and the occipital association areas as well as the right ventral prefrontal and inferior parietal regions. Target acquisition was associated with a different network involving activation of the caudate, putamen, and right dentate nucleus, as well as the left ventral prefrontal and inferior parietal areas. Antiparkinsonian therapy gave rise to changes in retrieval performance that correlated with network modulation (P< 0.01). Increases in network activation and learning performance occurred with internal pallidal deep brain stimulation (GPi DBS); decrements in these measures were present with levodopa. Our findings suggest that network analysis of activation data can provide stable descriptors of learning performance. Network quantification can provide an objective means of assessing the effects of therapy on cognitive functioning in neurodegenerative disorders. Hum. Brain Mapping 11:197–211, 2003. © 2003 Wiley‐Liss, Inc.
Microvascular free tissue transfer in elderly patients: The Toronto experience
Authors: Beausang Eamon S. , Ang Erik E. , Lipa Joan E. , Irish Jonathan C. , Brown Dale H. , Gullane Patrick J. , Neligan Peter C. 
Published: June 2003

AbstractBackground.Microvascular free tissue transfer has become an accepted and versatile method of reconstruction in the head and neck region, offering a one‐stage procedure and thus reducing the number and length of hospital stays. Many of the patients requiring head and neck free flaps are elderly, with concomitant medical problems, including respiratory and cardiovascular compromise, and are therefore potentially at higher risk of adverse outcomes. In addition, they frequently have a history of heavy alcohol and cigarette consumption, which can compound the risks.Methods.We analyzed a series of 288 intraoral free flap reconstructions and arbitrarily divided them into four groups depending on age: <50, 51–60, 61–70, >70. These reconstructions were all performed for malignant lesions. Preoperative medical problems, including ischemic heart disease, hypertension, chronic obstructive pulmonary disease, peripheral vascular disease, and diabetes, were assessed and compared among the different age groups.Conclusions.Our results suggest that free flap surgery is a safe technique in elderly patients with comparable surgical complications to a younger patient population. As a result of concomitant medical problems, however, postoperative medical complications are more frequent in the older age groups, with a resultant increase in length of hospital stay. © 2003 Wiley Periodicals, Inc. Head Neck 25: 549–553, 2003
Biodegradable polymer–mediated intratumoral delivery of cisplatin for treatment of human head and neck squamous cell carcinoma in a chimeric mouse model
Authors: Chen Fang‐An , Kuriakose M. Abraham , Zhou Ming‐Xing , DeLacure Mark D. , Dunn Richard L. 
Published: June 2003

AbstractBackground.The effectiveness of chemotherapeutic agents is proportional to the dose of the agents at their targets; however, the dose is limited by systemic toxicity. Attempts have been made to improve therapeutic effectiveness by increasing maximum tolerated dose (MTD) of chemotherapeutic agents using various local and regional drug delivery systems. Herein we report the use of an injectable biodegradable polymer to deliver cisplatin for intratumoral treatment of human head and neck squamous cell carcinoma (HNSCC) in a chimeric mouse model. The objectives of this research project were (1) to determine the release kinetics of cisplatin from the polymer delivery system, (2) to identify the MTD of polymer‐delivered cisplatin, and (3) to evaluate its therapeutic efficacy.Methods.To determine the in vivo release kinetics, cisplatin‐loaded polymer was injected subcutaneously into rats. Implants were removed and analyzed for remaining cisplatin by a high‐performance liquid chromatography technique. Sera from these rats were assayed for platinum by atomic absorption spectrophotometry. For MTD determination, SCID mice were engrafted subcutaneously with fresh biopsy specimens of HNSCC. Various doses of free or polymer‐loaded cisplatin were injected intratumorally. MTD was estimated based on the threshold at which all mice survived. The antitumor efficacy of free and polymer‐loaded cisplatin at their respective MTD was assayed on the same chimeric mouse model.Results.The polymer delivery system released 80% of the loaded cisplatin in vivo over a 7‐day period. The polymer‐delivered cisplatin exhibited higher MTD (36 mg/kg) than free cisplatin (18 mg/kg) and had a statistically significant tumor suppression effect compared with free cisplatin when used at their respective MTD.Conclusions.The polymer delivery system can sustain cisplatin release for a period of 7 days. It can increase MTD and potentially enhance the antitumor efficacy of cisplatin against human head and neck cancers. © 2003 Wiley Periodicals, Inc. Head Neck 25: 554–560, 2003
Anterior skull base surgery for malignant tumors: A multivariate analysis of 27 years of experience
Authors: Bentz Brandon G. , Bilsky Mark H. , Shah Jatin P. , Kraus Dennis 
Published: June 2003

AbstractIntroduction.Few studies have examined prognostic factors that have an impact on outcomes in anterior skull base surgery by multivariate analysis.Methods.We retrospectively examined our institution's skull base experience from 1973–2000.Results.During this time, 166 patients underwent an anterior skull base resection for malignancy (median age, 53 years; range, 6–92 years). The 5‐year relapse‐free and disease‐specific survival was 41% and 57% (median follow‐up, 53 months). Multivariate analysis found that dural invasion, primary histologic diagnosis, and margin status had a significant impact on relapse‐free and disease‐specific survival.Conclusions.These data indicate that patients with anterior skull base malignancies are treated successfully with skull base surgery. Patients demonstrating adverse prognostic variables such as dural invasion, adverse histologic findings, and/or positive margins should be considered for the addition of adjuvant therapy or innovative therapies as they become available in the future. © 2003 Wiley Periodicals, Inc. Head Neck 25: 515–520, 2003
The value of frozen section in intraoperative surgical management of thyroid follicular carcinoma
Authors: Došen Danijel , Turić Marko , Šmalcelj Josip , Janušić Renato , Pastorčić Grgić Marija , Šeparović Viktor 
Published: June 2003

AbstractBackground.Preoperative and intraoperative diagnosis of follicular carcinoma (FC), resulting in one‐stage surgical treatment of follicular thyroid tumors, is an important issue in thyroid surgery.Methods.In the 10‐year period there were 4158 operations performed on thyroid gland. There were 1559 patients with follicular tumors, 70 (4.4%) of them having FC. We analyzed the groups of patients with FC determined on frozen section (FS) and permanent section (PS) according to duration of clinical symptoms, ultrasound (US) examination, tumor size, patient gender and age, intensity of invasion, localization, and multiple or solitary occurrence of tumor.Results.FC was diagnosed in 39 (55.7%) patients on frozen section (FS). Among the encapsulated (minimal invasion) carcinomas, the FS was accurate in 19 of 33 (57.6%) FC and in 5 of 15 (27.8%) Hürthle cell carcinomas (HCC); among extensively invasive carcinoma in 11 of 14 (78.6%) FC and in 4 of 5 (80.0%) HCC. FC was significantly more common in men (p < .001) and in the right lobe (p < .05). We did not find statistically significant differences concerning duration of symptoms, US examination, tumor size, patient age, and multiple or solitary occurrence of the tumor between the patients with FC diagnosed on FS and the patients with FC diagnosed on PS.Conclusions.The intraoperative diagnosis of FC is difficult. Although the percentage of false‐negative results was relatively high (44.3%), there were no false‐positive results. This means that the second operation was avoided in 55.7% of the patients, and no unnecessary thyroidectomies were performed. FS biopsy is an important method in surgery of follicular tumors. Improved technical support and the ability to analyze a greater number of slides will increase the accuracy of the method. © 2003 Wiley Periodicals, Inc. Head Neck 25: 521–528, 2003
Total upper lip reconstruction with a free temporal scalp flap: Long‐term follow‐up
Authors: Chang Kao‐Ping , Lai Chung‐Sheng , Tsai Chih‐Cheng , Lin Tsai‐Ming , Lin Sin‐Daw 
Published: June 2003

AbstractBackground.In men, reconstruction of large full‐thickness defects of the upper lip requires both an inner layer to replace the mucosal lining and an outer hair‐bearing layer.Methods.When locating the superficial temporal vessels, the design of the temporal flap is marked following the hairline needed. After meticulously dissecting the flap, it is inset and microanastomosed with the facial blood vessels. The internal mucosal layer of the flap is grafted on. During the follow‐up period, the sensory recovery and motor functions are examined and recorded.Results.The postoperative courses were uneventful, and patients were satisfied with the results. One patient has a long follow‐up period of 18 years.Conclusions.The free temporal scalp hair‐bearing flap offers a reasonable alternative to conventional techniques in the reconstruction of large defects of the male upper lip or even a total upper lip. It is a single‐staged, relatively simple method of providing hair‐bearing skin to the upper lip. © 2003 Wiley Periodicals, Inc. Head Neck 25: 602–605, 2003
Parameters that predict local control after definitive radiotherapy for squamous cell carcinoma of the head and neck
Authors: Mendenhall William M. , Morris Christopher G. , Amdur Robert J. , Hinerman Russell W. , Mancuso Anthony A. 
Published: June 2003

AbstractPurpose.To analyze parameters that may influence the likelihood of local control after definitive radiotherapy for head and neck cancer.Methods.Between April 1980 and January 2000, 404 patients were treated with definitive RT alone (358 patients) or combined with adjuvant chemotherapy (46 patients) at our institution and were followed up for 0.25 to 20.25 years (median, 3.5 years.) All living patients were followed up for at least 2 years. All patients had the primary tumor volume calculated on pretreatment CT. End points were local control after RT and local control after RT without a severe late complication. Parameters evaluated in multivariate analyses of these end points included primary site, T stage, primary tumor volume, N stage, histologic differentiation, fractionation schedule, adjuvant chemotherapy, and gender.Results.The rates of local control and local control without a severe late complication after RT were significantly influenced by primary tumor volume for patients with cancer of the supraglottic larynx and true vocal cord. In contrast, the rates of local control and local control without severe complications for patients with tumors of the oropharynx and hypopharynx were less influenced by tumor volume. Multivariate analysis of the overall population revealed that the only parameter that was significantly related to the probability of local control after RT was T stage. Multivariate analyses stratified by primary site revealed that tumor volume significantly influenced local control for patients with cancers of the supraglottis (p= .0220) and glottis (p= .0042) but not for those with lesions of the tonsillar fossa/posterior tonsillar pillar (p= .0892), base of tongue (p= .9493), anterior tonsillar pillar/soft palate (p= .5909), and hypopharynx (p= .2282).Conclusions.The most important parameter that has an impact on local control after RT is T stage. Primary tumor volume also significantly influences the probability of local control in cancers of the supraglottis and glottis. © 2003 Wiley Periodicals, Inc. Head Neck 25: 535–542, 2003
Myofibroblastoma of the larynx: A study of two cases
Authors: MacGregor Allison R. , Batsakis John G. , El‐Naggar Adel K. 
Published: June 2003

AbstractBackground.We describe, for the first time, the occurrence of two pure examples of spindle cell neoplasm with fibrous and smooth muscle differentiation in the larynx.Materials and Method.Tissue sections from both tumors stained with hematoxylin and eosin were reviewed. Immunophenotypic analysis using keratin, S‐100 protein, SMA, and h‐Caldesmon markers was performed.Results.Tumors were seen as raised submucosal nodules in the glottic region of two elderly male patients. Histopathologically, the lesions were unencapsulated and composed of spindle cells that manifested variable cellular anaplasia and expressed SMA and were negative for keratin, S‐100, and h‐Caldesmon.Conclusions.We document histologically low‐grade malignant myofibroblastic tumors of the larynx. Complete excision is advised. © 2003 Wiley Periodicals, Inc. Head Neck 25: 606–611, 2003
The beverage maté: A risk factor for cancer of the head and neck
Authors: Goldenberg David , Golz Avishay , Joachims Henry Zvi 
Published: June 2003

AbstractBackground.Maté is a tealike beverage consumed habitually in South America and among South Americans throughout the world. It is brewed from the dried leaves and stemlets of the perennial tree Ilex paraguariensis (yerba maté), a species that belongs to the Aquifoliaceae family. Maté consumption has been associated with an increased rate of oral, oropharyngeal, esophageal, and laryngeal cancers. The purpose of this study is to review the literature and discuss the role of Maté consumption as a risk factor for head and neck cancers.Materials and Methods.We performed a thorough review of the relevant literature linking maté consumption with head and neck cancer and the proposed carcinogenicity of maté. Case control studies on maté‐drinking populations and in vivo and in vitro studies on the carcinogenicity of maté were reviewed. The populations included in many of these studies also used alcohol and tobacco products, confounding the influence of maté as an independent risk factor.Results.Evidence in the literature suggests that maté consumption is carcinogenic and plays a role in the development of cancers of the oral cavity, pharynx, larynx, and esophagus.Conclusions.The exact mechanism of carcinogenesis of maté is unknown. Both chemical and thermal carcinogenesis mechanisms have been suggested. Available information suggests that maté drinking is a risk factor for upper aerodigestive tract cancer. © 2003 Wiley Periodicals, Inc. Head Neck 25: 595–601, 2003