bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parkinsonism in multiple system atrophy: Natural history, severity (UPDRS‐III), and disability assessment compared with Parkinson's disease
Authors: Tison François , Yekhlef Farid , Chrysostome Virginie , Balestre Eric , Quinn Niall P. , Poewe Werner , Wenning Gregor K. 
Published: October 2002

AbstractWe analyzed parkinsonian features in multiple system atrophy (MSA) compared with age‐ and disease duration‐matched Parkinson's disease (PD) patients, and assessed the applicability of the Unified Parkinson's Disease Rating Scale (UPDRS) ‐III motor scale as a means of rating their severity. Cross‐sectional analysis of parkinsonism was done using UPDRS‐III, International Cerebellar Atatia Rating Scale, and disability scales (Hoehn and Yahr [H&A], Schwab and England, Katz and Lawton) in 50 unselected MSA patients and in 50 matched PD patients. At symptom onset, falls occurred 10 times more frequently in MSA, whereas limb tremor was 10 times more common in PD. At first visit (10.2 months), hemiparkinsonism and pill‐rolling rest tremor were less common in MSA. Hypomimia, atypical rest, postural or action tremor, as well as postural instability were more frequent in MSA. At study examination (62.4 months), parkinsonian signs in MSA patients were more frequently symmetrical and associated with axial rigidity, antecollis and postural instability. A levodopa response of >50% was seen in <10% of MSA patients. Modified H&Y stages (3.2 ± 1.3 vs. 2.2 ± 0.78) and UPDRS‐III scores (48.14 ± 19.5 vs. 31.74 ± 12.9) were significantly (P = 0.0001) higher in MSA. The internal consistency of the UPDRS‐III was fair in MSA patients (Cronbach's α >0.90), and correlated well with marked dependency on the Schwab and England and Katz and Lawton scales. Factor structure analysis of UPDRS‐III in MSA showed five clinically distinct subscores accounting for 74% of the variance, differing from PD by the dependency of the face–speech and limb bradykinesia items and independence of the postural–action tremor from the rest tremor items. There was a significant correlation (R2 = 0.70, P = 0.001) between ICARS ataxia and UPDRS‐III scores in MSA patients. Results confirm a distinct profile of parkinsonism in MSA and greater severity and disability compared with PD. It also indicates that the UPDRS‐III provides a useful severity measure of parkinsonism in MSA, albeit contaminated by additional cerebellar dysfunction. © 2002 Movement Disorder Society
Clinical, 18F‐dopa PET, and genetic analysis of an ethnic Chinese kindred with early‐onset parkinsonism and parkin gene mutations
Authors: Wu Ruey‐Meei , Shan Din‐E , Sun Chen‐Ming , Liu Ren‐Shyan , Hwu Wuh‐Liang , Tai Chun‐Hwei , Hussey Jennifer , West Andrew , Gwinn‐Hardy Katrina , Hardy John , Chen Judy , Farrer Matt , Lincoln Sarah 
Published: October 2002

AbstractWe report on clinical 18F‐labeled 6‐fluorodopa (18F‐dopa) positron emission tomography (PET) and molecular genetic analyses of an ethnic Chinese family in which three siblings presented with early‐onset Parkinson's disease. As described in some parkin patients, neither sleep benefit nor diurnal fluctuation was noted. Interestingly, depression, anxiety, and obsessive–compulsive disorders were manifest. The 18F‐dopa PET scans showed bilateral presynaptic dopaminergic dysfunction without marked lateralization. Molecular genetic analysis showed identical chromosome 6 haplotypes inherited by affected subjects, with alternate allelic deletions of parkin exons 3 and 4. Furthermore, mRNA analyses identified aberrantly spliced parkin transcripts, suggesting that unusual parkin protein isoforms may be expressed in the brain and retain some function. © 2002 Movement Disorder Society
A compact microstrip interdigital stepped‐impedance band‐pass filter with enhanced stop band
Authors: Crute John R. , Davis Lionel E. 
Published: October 2002

AbstractMicrostrip bandpass filters are widely used in a variety of microwave subsystems to select a desired band of frequencies. However, common filter topologies with uniform impedance resonators exhibit poor stop‐band performance. This is due to the occurrence of harmonic passbands at multiples of the fundamental passband frequency. This study describes the design of a compact interdigital microstrip filter, using short‐circuit stepped‐impedance resonators (SCSIRs) to enhance the harmonic stop‐band response. Measurements on an experimental filter, with a design center frequency of 2442 MHz and 3‐dB bandwidth of 611 MHz (25%), show an increase in the first harmonic passband frequency to 8809 MHz. At three times the fundamental passband center frequency (7326 MHz), stop‐band attenuation is better than −35 dB. The results demonstrate the usefulness of SCSIRs for improving the stop‐band performance of interdigital bandpass filters, with only a small increase in overall size. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 336–340, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10455
Activity of postoperative carboplatin, etoposide, and high‐dose methotrexate in pediatric CNS embryonal tumors: Results of a phase II study in newly diagnosed children
Authors: Kellie Stewart J. , Wong Christopher K.F. , Pozza Luciano Dalla , Waters Keith D. , Lockwood Liane , Mauger David C. , White Les 
Published: October 2002

AbstractBackgroundChemotherapy is used as an alternative to irradiation or to minimize the irradiation exposure among infants with medulloblastoma or other CNS embryonal tumors. Adjuvant chemotherapy is commonly used in older children with high‐risk medulloblastoma to improve survival or to allow a reduction in the craniospinal irradiation dose in standard‐risk patients. However, optimal multimodality therapy, including the precise role of chemotherapy, has not been defined for these groups of patients. The objective of the present study is to assess the efficacy and toxicity of four postoperative courses of carboplatin, etoposide, and high‐dose methotrexate in newly diagnosed children with medulloblastoma or other CNS embryonal tumors.ProcedureTwenty‐eight children, aged from 0.3 to 15.9 years (median, 6.2 years) with post‐operative measurable residual CNS embryonal tumors were enrolled, comprising medulloblastoma (n = 19), supratentorial PNET (n = 7), and pineoblastoma (n = 2). Post‐operative chemotherapy comprised carboplatin 350 mg/m2 and etoposide 100 mg/m2 on Days 1 & 2, and methotrexate 8 g/m2 on Day 3, repeated at 21–28‐day intervals for a total of four courses. Therapy following completion of the initial Phase II study was influenced by patient age and investigator preference.ResultsThe combined complete response rate (CR, 7/19) and partial response rate (PR, 7/19) was 74% in patients with medulloblastoma, 89% for patients with PNET/pineoblastoma (CR, 2/9 and PR, 6/9), and for all patients it was 79%. Patients aged < 3 years at diagnosis had a combined PR and CR rate of 71% compared to 81% in patients aged > 3 years. Treatment was well tolerated although myelosuppression and thrombocytopenia were common.ConclusionsThe combination of carboplatin, etoposide, and high‐dose methotrexate is highly active in pediatric patients with CNS embryonal tumors. Med Pediatr Oncol 2002;39:168–174. © 2002 Wiley‐Liss, Inc.
Theory of nonexponential NMR signal decay in liver with iron overload or superparamagnetic iron oxide particles
Authors: Jensen J.H. , Chandra R. 
Published: October 2002

AbstractA quantitative theory is proposed for the nonexponential NMR proton signal decay observed in liver with iron overload or superparamagnetic iron oxide particles. This effect occurs for Carr‐Purcell‐Meiboom‐Gill (CPMG) sequences and is argued to be a direct consequence of the strong magnetic field inhomogeneities generated by the iron, rather than being due to tissue compartments. An approximate mathematical form is given for the signal decay, which is fit to experimental data for samples of rat liver with iron oxide particles, for samples of marmoset liver with hemosiderosis, and for in vivo human liver with hereditary hemochromatosis. The fitting parameters obtained are consistent with the pattern of iron deposition determined from histology. For the case of hereditary hemochromatosis, a good correlation is found between a parameter characterizing the nonexponential decay and the iron concentration. Implications for practical MR quantification of hepatic iron are discussed. Magn Reson Med 47:1131–1138, 2002. © 2002 Wiley‐Liss, Inc.
Generalized autocalibrating partially parallel acquisitions (GRAPPA)
Authors: Griswold Mark A. , Jakob Peter M. , Heidemann Robin M. , Nittka Mathias , Jellus Vladimir , Wang Jianmin , Kiefer Berthold , Haase Axel 
Published: October 2002

AbstractIn this study, a novel partially parallel acquisition (PPA) method is presented which can be used to accelerate image acquisition using an RF coil array for spatial encoding. This technique, GeneRalized Autocalibrating Partially Parallel Acquisitions (GRAPPA) is an extension of both the PILS and VD‐AUTO‐SMASH reconstruction techniques. As in those previous methods, a detailed, highly accurate RF field map is not needed prior to reconstruction in GRAPPA. This information is obtained from several k‐space lines which are acquired in addition to the normal image acquisition. As in PILS, the GRAPPA reconstruction algorithm provides unaliased images from each component coil prior to image combination. This results in even higher SNR and better image quality since the steps of image reconstruction and image combination are performed in separate steps. After introducing the GRAPPA technique, primary focus is given to issues related to the practical implementation of GRAPPA, including the reconstruction algorithm as well as analysis of SNR in the resulting images. Finally, in vivo GRAPPA images are shown which demonstrate the utility of the technique. Magn Reson Med 47:1202–1210, 2002. © 2002 Wiley‐Liss, Inc.
MRI cardiac tagging using a sinc‐modulated RF pulse train
Authors: Wu Ed X. , Towe Christopher W. , Tang Haiying 
Published: October 2002

AbstractA method of spatial modulation of magnetization using the RF pulse train is described for improved cardiac tagging. The method is based on a sinc‐modulated RF pulse train in the presence of constant gradient. Such an RF pulse train yields a rectangular profile of saturated magnetization, and the bandwidth of the sinc envelope controls the width of the saturation tag. Compared to DANTE and SPAMM tagging techniques, this method offers sharper‐edged tags and the ability to change the ratio of tag width to tag separation. The approach was implemented on a 9.4 T vertical bore NMR system and demonstrated with both phantom and in vivo mouse heart studies. Magn Reson Med 48:389–393, 2002. © 2002 Wiley‐Liss, Inc.
CD11b+ neutrophils predominate over RAM11+ macrophages in stretch‐injured muscle
Authors: St. Pierre Schneider Barbara , Brickson Stacey , Corr David T. , Best Thomas 
Published: October 2002

AbstractThe purpose of this study was to determine whether both neutrophils and macrophages infiltrate the hematoma site of stretch‐injured rabbit tibialis anterior muscle. The Mab.198 antibody was used to detect CD11b+ neutrophils or macrophages. Neutrophils were identified specifically by using the RPN3/57 antibody. The RAM11 antibody was used to detect macrophages. The histological characteristics of the hematoma site, torn fibers or inflammatory cells, were present primarily at 4 and 24 h, but not at 48 and 72 h after injury. A difference in the Mab.198+ cellular concentration was detected over time between uninjured and injured muscles (P = 0.03). The injured‐uninjured difference in the RPN3/57+ or RAM11+ cellular concentrations approached significance (P = 0.07) or else was deemed insignificant (P = 0.13), respectively. Therefore, neutrophils may predominate over RAM11+ macrophages in stretch‐injured muscle. These findings may influence the antiinflammatory strategies used to treat stretch injuries. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 837–844, 2002
Effect of triggering potential on calculations of jitter in single‐fiber EMG
Authors: Baslo M. Bariş , Yildiz Nebil , Yalinay Pinar , Ertaş Mustafa 
Published: October 2002

AbstractJitter values are calculated in reference to a triggering potential during single‐fiber electromyography (SFEMG) performed during voluntary contraction. When there are more than two single‐fiber action potentials (SFAP) and the selected triggering potential is from an abnormal end‐plate, all the jitters calculated from the same trace will be affected. In this study, the effect of triggering potential on calculated jitter was investigated in myasthenic and healthy volunteers by switching the triggering potential and recalculating the jitter off‐line. Selecting a triggering potential from an abnormal end‐plate increased the number of abnormal individual jitters as well as the mean jitter. Therefore, if the equipment software has the capacity to change the trigger potential, the triggering potential should not be from an abnormal end‐plate if all possible jitter values are to be calculated for traces having three or more single‐fiber potentials. Otherwise, only one jitter value should be included from any one trace to prevent false‐positive results. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
Modelling of anisotropic damage in brittle rocks under compression dominated stresses
Authors: Lu Y.F. , Shao J.F. 
Published: October 2002

AbstractA new model for describing induced anisotropic damage in brittle rocks is proposed. Although phenomenological, the model is based on physical grounds of micromechanical analysis. Induced damage is represented by a second rank tensor, which is related to the density and orientation of microcracks. Damage evolution is related to the propagation condition of microcracks. The onset of microcrack coalescence leading to softening behaviour is also considered. The effective elastic compliance of the damaged material is obtained from a specific form of Gibbs potential. Irreversible damage‐related strains due to residual opening of microcracks after unloading are also captured. All the model's parameters could be determined from conventional triaxial compression tests. The proposed model is applied to a typical brittle rock. Comparison between test data and numerical simulations shows an overall good agreement. The proposed model is able to describe the main features related to induced microcracks in brittle geomaterials. Copyright © 2002 John Wiley & Sons, Ltd.
Length‐constrained path‐matchings in graphs
Authors: Ghodsi M. , Hajiaghayi M. T. , Mahdian M. , Mirrokni V. S. 
Published: October 2002

AbstractThe path‐matching problem is to find a set of vertex‐ or edge‐disjoint paths with length constraints in a given graph with a given set of endpoints. This problem has several applications in broadcasting and multicasting in computer networks. In this paper, we study the algorithmic complexity of different cases of this problem. In each case, we either provide a polynomial‐time algorithm or prove that the problem is NP‐complete. © 2002 Wiley Periodicals, Inc.
Initial stages of radial glia astrocytic transformation in the early postnatal anterior subventricular zone
Authors: Alves José A. J. , Barone Patrick , Engelender Simone , Fróes Maira M. , Menezes João R. L. 
Published: October 2002

AbstractIn the early postnatal subventricular zone (SVZ), two seemingly unrelated events occur simultaneously: a massive tangential migration of neuroblasts towards the olfactory bulb, known as the rostral migratory stream (RMS), and the outward movement of radial glia (RG) undergoing astrocytic transformation. Because of the orthogonal arrangement between these two sets of cells, little, if any, relevance has been ascribed for their possible interactions. By depositing DiI at the pial surface we have studied RG transformation within the SVZ/RMS, from birth up to the end of the first postnatal week. While still within the SVZ/RMS, RG morphology changed from simple bipolar to highly complex branched profiles, attaining their highest degree of complexity at the interface of the SVZ with the overlying white matter. At this interface cell bodies of radial glia accumulate and their processes run tangentially, surrounding the SVZ/RMS. Processes of RG surrounding the SVZ/RMS could also be observed by immunostaining for vimentin, GFAP, and nestin. In contrast, in the white matter all DiI‐labeled RG presented a simple bipolar profile. These results indicate that the outward radial migration of the transforming RG does not occur uniformly. Instead, the different morphologies and cell densities that RG assume when they cross the SVZ/RMS and overlying white matter imply different migratory behaviors. Finally, our data suggest that RG provide a cellular scaffold to the early postnatal SVZ/RMS, much in the same way as astrocytes in the adult RMS. © 2002 Wiley Periodicals, Inc. J Neurobiol 52: 251–265, 2002
Solving 2D transient rolling contact problems using the BEM and mathematical programming techniques
Authors: González José A. , Abascal Ramón 
Published: October 2002

AbstractThis work presents a new approach to the transient rolling contact of two‐dimensional elastic bodies. A solution will be obtained by minimizing a general B‐differentiable function representing the equilibrium equations and the contact conditions at each time step. Inertial effects are not taken into account and the boundary element method is used to compute the elastic influence coefficients of the surface points involved in contact (equilibrium equations). The contact conditions are represented with the help of variational inequalities and projection functions. Finally, the minimization problem is solved using the Generalized Newton's Method with line search. The results are compared with some example problems and the influence of discretization and integration time step on the results is discussed. Copyright © 2001 John Wiley & Sons, Ltd.
An implicit BEM formulation for gradient plasticity and localization phenomena
Authors: Benallal Ahmed , Fudoli Carlos A. , Venturini Wilson S. 
Published: October 2002

AbstractThe aim of this paper is to discuss a boundary element formulation for non‐linear structural problems involving localization phenomena. In order to overcome the well‐known mesh dependency observed in local plasticity, a gradient plasticity model is used. An implicit boundary element formulation is proposed and the underlying consistent tangent operator defined. This formulation is based on the classical displacement and strain integral representations combined with an integral representation of the plastic multiplier. First numerical examples are presented to illustrate the application of the method. Copyright © 2001 John Wiley & Sons, Ltd.
Implicit stress integration procedure for small and large strains of the Gurson material model
Authors: Kojic Milos , Vlastelica Ivo , Zivkovic Miroslav 
Published: October 2002

AbstractThe Gurson material model has broad applications in fracture mechanics, large strain deformations and failure of metals. Void growth and void nucleation are included in the model considered in this paper. An implicit stress integration procedure with calculation of the consistent tangent moduli is developed for the Gurson model. The general 3D deformations and the plane stress conditions are considered. The procedure is robust, simple and computationally efficient, suitable for use within the finite element method (FEM). It represents an application of the governing parameter method (GPM) for stress integration in case of inelastic material deformation. A large strain formulation, based on the multiplicative decomposition of the deformation gradient for material with plastic change of volume and logarithmic strains, is used in the paper. The developed numerical procedure for stress integration is applicable to small and large strains conditions. Solved examples illustrate the main features of the developed numerical algorithm. Copyright © 2002 John Wiley & Sons, Ltd.
Simulation of oscillatory wall shear stress in channels with moving indentations
Authors: Ng E. Y. K. , Siauw W. L. , Chong C. K. 
Published: October 2002

AbstractThe aim of this paper is to study the effects of a periodically, excited wall on the oscillatory nature of wall shear stress (WSS) and flow structures. A non‐Newtonian incompressible Navier–Stokes (N–S) solver with moving boundary was developed using Fasttalk language within the Fastflo environment. It was based on the methods of operator splitting and artificial compressibility with consideration to retain space conservation property. A two‐dimensional channel having a dimension of a human femoral artery but with arbitrarily assigned wall movement was employed. The Newtonian version of the code was validated against published work by simulation of flow in this channel with time‐varying upper and lower walls. Non‐Newtonian models (approximately 45% haematocrit) of blood flow were performed for comparison. The code was then applied to a channel with a fixed, straight, upper wall and a moving indenting lower wall. Flow separation, stagnation, and unsteadiness were characteristic flow features observed in this study. The Power Law model showed higher shear‐thinning effect at any time the frame produced the smallest vortices. The Casson model produced the highest WSS which was oscillatory in nature. When the upper wall was fixed, the indenting wall experienced almost twice as much as an induced oscillatory WSS as the rigid wall. The result also suggested that periodic wall movement is a mechanism of producing oscillatory WSS. This study may provide probable insights on atherogenesis, while the solution scheme may be useful in vascular biology. Copyright © 2002 John Wiley & Sons, Ltd.
Difference in bound rubber formation of silica and carbon black with styrene‐butadiene rubber
Authors: Choi Sung‐Seen 
Published: October 2002

AbstractFormation of bound rubber is affected by the physical structure and surface chemistry of filler and the property of rubber. Variation of the bound rubber formation in styrene‐butadiene rubber compounds filled with silica and/or carbon black was studied. Influence of temperature on extraction of loosely bound rubber was also investigated. For the both silica and carbon black‐filled compounds, the bound rubber content increases with increase in the silica content ratio. The bound rubber content decreases with increasing the extracting temperature. The loosely bound rubber content of the silica‐filled compound is higher than that of the carbon black‐filled one. Activation energy for the extraction of the unbound and loosely bound rubbers becomes higher as the total filler content increases. The activation energy of the silica‐filled compound is higher (almost double the value) than for the carbon black‐filled one. Copyright­© 2002 John Wiley & Sons, Ltd.