bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bilateral intraneural perineurioma presenting as ulnar neuropathy at the elbow
Authors: Beekman Roy , Slooff Willem‐Bart M. , Van Oosterhout Matthijs F. M. , Lammens Martin , Van Den Berg Leonard H. 
Published: May 2004

AbstractWe describe a 36‐year‐old woman with progressive bilateral ulnar neuropathy. Sonographic and magnetic resonance imaging studies revealed extensive focal ulnar nerve enlargement at the elbow. Histological studies gave evidence of an intraneural perineurioma. Because intraneural perineurioma usually appears as a single mass lesion at sites other than typical entrapment sites, this mode of presentation is unusual. We discuss the nature of this benign tumor and the differential diagnosis of nerve enlargement. Knowledge of possible causes of nerve thickening is crucial when performing imaging in patients with neuropathies. Muscle Nerve 30: 239–243, 2004
Urinary bladder volumetry by means of a single retrosymphysically implantable ultrasound unit
Authors: Seif C. , Herberger B. , Cherwon E. , Martinez Portillo F.J. , Molitor M. , Stieglitz T. , Böhler G. , Zendler S. , Jünemann K.P. , Braun P.M. 
Published: May 2004

AbstractAimsOptimal voiding is a crucial issue for patients with neurogenic bladder dysfunctions to prevent long‐term damage to the urinary tract. In prior studies, implantable ultrasound (US) sensors have proved an appropriate method of measuring the urinary bladder volume. Their disadvantage is that they tend to dislocate in chronic applications as they are fixed directly onto the bladder wall. In the present study, we describe an implantable US volumetry unit that does not require fixing to the bladder wall and consists of a single receiver‐transmitter unit.Materials and MethodsSix Göttinger minipigs were anesthetized in ITN; a sensor was stitched behind the symphysis into the periosteum and aligned to the bladder so that an US measurement could take place in ventro‐dorsal direction. In steps of 50 ml, the bladder was filled up to 250 ml via a transurethral catheter; after each filling step the volume was measured three times and compared to the instilled volume.ResultsOn average the measurements with implanted US differed from the actual bladder filling by 77.4% at a bladder filling of 50 ml (“error” messages were included as 0 ml), 3.8% at 100 ml, 3.8% at 150 ml, and 0.3% at 200 ml, and 3.6% at 250 ml. When the empty bladder (= 0 ml) was measured, the US sensor detected no volume in 73% of the cases.ConclusionsIn our animal model, the above‐described US system proved tantamount with other external US measuring units and presented a precise and low‐artefact system, allowing reliable measuring of the urinary volume with good chances of preserving these positive qualities over time. We expect that clinical application of this system may help to determine the optimal voiding time and thus to avoid bladder overextension and damage to the urinary tract over time. © 2004 Wiley‐Liss, Inc.
Pycnogenol® and vitamin E inhibit ethanol‐induced apoptosis in rat cerebellar granule cells
Authors: Siler‐Marsiglio Kendra I. , Shaw Gerry , Heaton Marieta B. 
Published: May 2004

AbstractPycnogenol® (PYC), a patented combination of bioflavonoids extracted from the bark of French maritime pine (Pinus maritima), scavenges free radicals and promotes cellular health. The protective capacity of PYC against ethanol toxicity of neurons has not previously been explored. The present study demonstrates that in postnatal day 9 (P9) rat cerebellar granule cells the antioxidants vitamin E (VE) and PYC (1) dose dependently block cell death following 400, 800, and 1600 mg/dL ethanol exposure (2) inhibit the ethanol‐induced activation of caspase‐3 in the same model system; and (3) reduce neuronal membrane disruption as assayed by phosphatidylserine translocation to the cell surface. These results suggest that both PYC and VE have the potential to act as therapeutic agents, antagonizing the induction of neuronal cell death by ethanol exposure. © 2004 Wiley Periodicals, Inc. J Neurobiol 59: 261–271, 2004
Expression of functional kainate and AMPA receptors in developing lateral superior olive neurons of the rat
Authors: Vitten Harald , Reusch Margret , Friauf Eckhard , Löhrke Stefan 
Published: May 2004

AbstractA functional analysis of AMPA and kainate receptors (AMPARs and KARs) in the lateral superior olive (LSO), a major nucleus in the auditory brainstem, has not been performed so far, to our knowledge. Here we investigated the presence and characteristics of such receptors in the rat LSO by means of whole‐cell patch‐clamp recordings in combination with pharmacology. Current responses evoked by 200 μM AMPA were completely blocked by the specific AMPAR antagonist GYKI 52466 (100 μM). Properties of the AMPAR‐mediated currents (latency, activation time constant, and peak amplitude) remained constant between postnatal day 3 (P3) and P10. Current responses evoked by 100 μM KA were not completely blocked by 100 μM GYKI 52466, indicating that the residual component was mediated by KARs. Throughout development, two groups of KAR‐mediated currents (fast IKA and slow IKA) were distinguished because they had significantly different mean activation time constants. Moreover, the mean peak amplitude of fast IKA was significantly higher than that of slow IKA. The differentiation into fast IKA and slow IKA can be explained by the existence of two groups of LSO neurons displaying different KAR densities, distributions, and/or diverse types with differences in conductance. Application of the specific KAR subunit agonists SYM 2081 (10 μM), ATPA (10 μM), or iodowillardiine (1 μM) evoked currents in almost all cells tested, showing that GluR5 subunits are a component of functional KARs in LSO neurons. Electrical stimulation of ipsilateral input fibers in the presence of KAR antagonists (NS‐102 and GAMS), modulators (WGA), or GYKI 52466 revealed the presence of synaptic KARs in LSO neurons. © 2004 Wiley Periodicals, Inc. J Neurobiol 59: 272–288, 2004
Boundary element formulation for 3D transversely isotropic cracked bodies
Authors: Ariza M. P. , Dominguez J. 
Published: May 2004

AbstractThe boundary traction integral representation is obtained in elasticity when the classical displacement representation is differentiated and combined according to Hooke's law. The use of both traction and displacement integral representations leads to a mixed (or dual) formulation of the BEM where the discretization effort for crack problems is much smaller than in the classical formulation. A boundary element analysis of three‐dimensional fracture mechanics problems of transversely isotropic solids based on the mixed formulation is presented in this paper. The hypersingular and strongly singular kernels appearing in the formulation are regularized by using two terms of the displacement series expansion and one term of the traction expansion, at the collocation point. All the remaining integrals are analytically evaluated or transformed by means of Stokes' theorem into regular or weakly singular integrals, which are numerically computed. The method is general and can be used for elements of any shape including quarter‐point crack front elements. No change of co‐ordinates is required for the integration. The formulation as presented in this paper is something as clear, general and easy to handle as the classical BE formulation. It is used in combination with three‐dimensional quadratic and quarter‐point elements to obtain accurate results for several different crack problems. Cracks in boundless and finite transversely isotropic domains are studied. The meshes are simple and include only discretization of the crack and the external boundary. The obtained results are in good agreement with those existing in the literature. Copyright © 2004 John Wiley & Sons, Ltd.
On singularities in the solution of three‐dimensional Stokes flow and incompressible elasticity problems with corners
Authors: Dimitrov A. 
Published: May 2004

AbstractIn this paper, a numerical procedure is presented for the computation of corner singularities in the solution of three‐dimensional Stokes flow and incompressible elasticity problems near corners of various shape. For obtaining the order and mode of singularity, a neighbourhood of the singular point is considered with only local boundary conditions. The weak formulation of this problem is approximated using a mixed u, p Galerkin–Petrov finite element method. Additionally, a separation of variables is used to reduce the dimension of the original problem. As a result, the quadratic eigenvalue problem (P+λQ+λ2R)d=0 is obtained, where the saddle‐point‐type matrices P, Q, R are defined explicitly. For a numerical solution of the algebraic eigenvalue problem an iterative technique based on the Arnoldi method in combination with an Uzawa‐like scheme is used. This technique needs only one direct matrix factorization as well as few matrix–vector products for finding all eigenvalues in the interval 𝓈(λ) ∈ (−0.5, 1.0), as well as the corresponding eigenvectors. Some benchmark tests show that this technique is robust and very accurate. Problems from practical importance are also analysed, for instance the surface‐breaking crack in an incompressible elastic material and the three‐dimensional viscous flow of a Newtonian fluid past a trihedral corner. Copyright © 2004 John Wiley & Sons, Ltd.
The ultraweak time coupling in non‐linear multiphysics modelling and related optimization problems
Authors: Favennec Y. , Labbé V. , Bay F. 
Published: May 2004

AbstractThis paper presents different strategies in order to solve forward direct and backward adjoint problems when dealing with coupled time‐dependent electromagnetic and heat transfer phenomena, as well as related optimization problems. It is shown that the use of the fully discretized gradient method is judicious since the obtained gradient is exact while any other method yield to approximations of the gradient. The use of the ultraweak coupling and of the discretized gradient have been validated through different tests dealing with direct modelling, parameter identification and optimization. Copyright © 2004 John Wiley & Sons, Ltd.
Computational method for atomistic homogenization of nanopatterned point defect structures
Authors: Chung Peter W. 
Published: May 2004

AbstractThe development of an approximation method that rigorously averages small‐scale atomistic physics and embeds them in large‐scale mechanics is the principal aim of this work. This paper presents a general computational procedure based on homogenization to average frozen nanoscale atomistics and couple them to the equations of continuum hyperelasticity. The proposed application is to nanopatterned systems in which complex atomic configurations are organized in a repeating periodic array. The finite element method is used to solve the equations at the large scale, but the small‐scale equation is representative of lattice‐statics. The method is predicated on a quasistatic zero‐temperature assumption and, through homogenization, leads to a coupled set of variational equations. The numerical procedure is presented in detail, and 2‐D examples of ultra thin film layers of carbon one atom thick are shown to illustrate its applicability. Homogenization naturally gives rise to an inner displacement term with which point defects are explicitly modelled and their non‐linear interactions with global states of multiaxial strain are studied. Published in 2004 by John Wiley & Sons, Ltd.
Optimal patterns of glider dynamic soaring
Authors: Zhao Yiyuan J. 
Published: May 2004

AbstractThis paper presents optimal patterns of glider dynamic soaring utilizing wind gradients. A set of three‐dimensional point‐mass equations of motion is used and basic glider performance parameters are identified through normalizations of these equations. In particular, a single parameter is defined that represents the combined effects of air density, glider wing loading, and wind gradient slope. Glider dynamic soaring flights are formulated as non‐linear optimal control problems and three performance indices are considered. In the first formulation, the completion time of one cycle of dynamic soaring is minimized subject to glider equations of motion, limitations on glider flights, and appropriate terminal constraints that enforce a periodic dynamic soaring flight. In the second formulation, the final altitude after one cycle of dynamic soaring is maximized subject to similar constraints. In the third formulation, the least required wind gradient slope that can sustain an energy‐neutral dynamic soaring flight is determined. Different terminal constraints are used to produce basic, travelling, and loiter dynamic soaring patterns. These optimal control problems are converted into parameter optimization via a collocation approach and solved numerically with the software NPSOL. Different patterns of glider dynamic soaring are compared in terms of cycle completion time and altitude‐increasing capability. Effects of wind gradient slope and wind profile non‐linearity on dynamic soaring patterns are examined. Copyright © 2004 John Wiley & Sons, Ltd.
Optimal dynamic irrigation schemes
Authors: Shani Uri , Tsur Yacov , Zemel Amos 
Published: May 2004

AbstractOptimal control methods are employed to derive irrigation management schemes accounting both for the dynamic response of the biomass yield to soil moisture and for the cost of irrigation water. Moisture dynamics depend on the irrigation rate and on the current biomass and moisture states. We find that the optimal irrigation policy has turnpike characteristics: soil moisture in the root zone should be brought to some optimal target level as rapidly as possible and kept at that level until some time prior to harvest, when irrigation should be ceased. The target moisture level and the stopping time vary across crops, soil types, climatic conditions and economic (price) factors, but the turnpike structure of the optimal irrigation policy persists under general circumstances. An empirical example demonstrates that the optimal scheme significantly outperforms the policy of yield maximization in actual practice. Copyright © 2004 John Wiley & Sons, Ltd.
Polymorphism within the glutathione S‐transferase P1 gene is associated with increased susceptibility to childhood malignant diseases
Authors: Zielińska Elżbieta , Zubowska Małgorzata , Bodalski Jerzy 
Published: May 2004

AbstractBackgroundGlutathione S‐transferases (GSTs) are involved in the metabolism of carcinogens and anticancer drugs. Functional polymorphisms exist in at least three genes that code for the GSTs, such as the GSTM1 and GSTT1 gene deletions or the A–G transition within the GSTP1 gene, which represents distinct GSTP1a and GSTP1b alleles. In the present case‐control study, we aimed at estimation of the relationship between the GSTM1, GSTT1, and GSTP1 genotypes and the susceptibility to various types of childhood malignancies and the early relapses of diseases.ProcedureUsing the polymerase chain reaction on the DNA extracted from peripheral blood leukocytes, we identified the GSTM1, GSTT1, and GSTP1 genotypes in 234 children at the initial stage of a childhood malignancy as well as in 460 age‐and sex‐matched healthy subjects who served as controls. The follow‐up period for the effects of the anticancer therapy ranged from 11 to 43 months.ResultsCompared to the controls, a significant increase in the frequency of the GSTP1b/GSTP1b genotype (odds ratio (OR) 5.7; 95% confidence limit (CL) from 2.4 to 13.8; Pearsons Chi‐square P = 0.0001) was detected in the children with neoplasms. The GSTM1 and GSTT1 genotypes did not show any correlation with the risk of the de novo diagnosed neoplasms. During the observation, 62 children (26%) were found to be present with a local or disseminated recurrence of the diseases. The analysis indicated a trend in increasing risk of relapse for carriers of the GSTP1a allele (OR = 3.29; 95% CL from 0.73 to 14.67 P = 0.03).ConclusionsOur results support the hypothesis that GST genotype affects etiology and outcome of a variety of childhood malignancies. © 2004 Wiley‐Liss, Inc.
On the non‐monotonic lateral size dependence of the height of GaAs nanowhiskers grown by molecular beam epitaxy at high temperature
Authors: Dubrovskii V. G. , Soshnikov I. P. , Cirlin G. E. , Tonkikh A. A. , Samsonenko Yu. B. , Sibirev N. V. , Ustinov V. M. 
Published: May 2004

AbstractGaAs nanowhiskers were grown by molecular beam epitaxy on the GaAs(111)B surface activated by Au at the surface temperature of 585 °C. The dependence of nanowhisker height on the size of Au–GaAs alloy drops was investigated. It has been found that the height of GaAs nanowhiskers is zero at a certain minimum diameter of drop, then increases with size, has a pronounced maximum at a certain size, decreases for thicker whiskers and finally goes to a certain asymptotic value. The theoretical model for the growth kinetics of nanowhiskers was developed in order to explain the observed size dependence. The results of comparison of theoretical and experimental data for the height of GaAs nanowhiskers are presented and analyzed. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Post‐source decay matrix‐assisted laser desorption/ionization mass spectrometric study of tetracyclic 2,3‐dihydro‐1,5‐benzothiazepines
Authors: Kéki Sándor , Nagy Lajos , Deák György , Lévai Albert , Zsuga Miklós 
Published: May 2004

AbstractThe fragmentation behavior of six tetracyclic 2,3‐dihydro‐1,5‐benzothiazepine derivatives cationized with protons and silver ions under post‐source decay (PSD) matrix‐assisted laser desorption/ionization (MALDI) conditions is reported. The protonated adduct ions decompose into several structurally important fragment ions, including substituted cyclopropane and benzohydrothiazole cations. Elimination of Ag and H and/or AgH from the silver‐cationized adduct ions of these ([M+Ag]+) compounds was observed. It was also found that [M+Ag]+ produced silver‐depleted fragment ions exclusively. Based on the PSD results a fragmentation pathway is proposed for the [M+H]+ and [M+Ag]+ precursor ions. Copyright © 2004 John Wiley & Sons, Ltd.
Semi‐automated quantification of ivermectin in rat and human plasma using protein precipitation and filtration with liquid chromatography/tandem mass spectrometry
Authors: Pereira Tony , Chang Steve W 
Published: May 2004

AbstractIvermectin is a parasiticide commonly used in humans and livestock. It is currently under development for the treatment of pediculosis of humans (head lice) that does not respond to established treatments. A liquid chromatography/turbo ion spray tandem mass spectrometry (LC/TIS‐MS/MS) method for the determination of ivermectin in rat and human plasma has been developed that uses emamectin [4″‐epi‐(methylamino)‐4″‐deoxyavermectin] as the internal standard. Sample preparation involved protein precipitation and filtration of fortified plasma in the 96‐well format. Chromatographic separation was accomplished using fast gradient conditions on a C8 stationary phase. The analytes were detected with the mass spectrometer operated in the positive ion, multiple reaction monitoring mode. The method exhibited good intra‐ and interday accuracy and precision, and was linear over a dynamic range of 1–2000 ng/mL. In rat plasma, intraday accuracy ranged between 84–93% for the low quality control (QC) sample (1.5 ng/mL), and between 91–109% for the remaining QCs. Intraday precision ranged between 4.9–15% for the low QC, and 0.8–6.3% for the remaining QCs. Interday accuracy ranged between 88–107%, and precision between 4.1–11%. Similar data was obtained using human plasma. An investigation of matrix effects indicated that the ionization efficiency of ivermectin was favored by the presence of an ammonium ion in an aqueous environment. The implications of this observation toward assay sensitivity are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Quadratic form of stable sub‐manifold for power systems
Authors: Cheng Daizhan , Ma Jin , Lu Qiang , Mei Shengwei 
Published: May 2004

AbstractThe stable sub‐manifold of type‐1 unstable equilibrium point is fundamental in determining the region of attraction of a stable working point for power systems, because such sub‐manifolds form the boundary of the region (IEEE Trans. Automat. Control 1998; 33(1):16–27; IEEE Trans. Circuit Syst. 1988; 35(6):712–728). The quadratic approximation has been investigated in some recent literatures (Automatica 1997; 33(10):1877–1883; IEEE Trans. Power Syst. 1997; 12(2):797–802). First, the paper reports our recent result: a precise formula is obtained, which provides the unique quadratic approximation with the error of 0(∣∣x∣∣3). Then the result is applied to differential–algebraic systems. The real form of practical large scale power systems are of this type. A detailed algorithm is obtained for the quadratic approximation of the stable sub‐manifold of type‐1 unstable equilibrium points of such systems. Some examples are presented to illustrate the algorithm and the application of the approximation to stability analysis of power systems. Copyright © 2004 John Wiley & Sons, Ltd.
Brief report: Construct validity of two identity status measures: the EIPQ and the EOM‐EIS‐II
Authors: Schwartz Seth J. 
Published: May 2004

AbstractThe present study was designed to examine construct validity of two identity status measures, the Ego Identity Process Questionnaire (EIPQ; J. Adolescence 18 (1995) 179) and the Extended Objective Measure of Ego Identity Status II (EOM‐EIS‐II; J. Adolescent Res. 1 (1986) 183). Construct validity was operationalized in terms of how identity status classifications generated by the EIPQ and EOM‐EIS related to a measure of psychological agency, the Multi‐Measure Agentic Personality Scale (MAPS; J. Adolescence 20 (1997) 421). Results indicated that, for the most part, the agentic personality scales differentiated the EIPQ diffused and moratorium statuses from the foreclosed and achieved statuses, whereas the agentic personality scales differentiated the EOM‐EIS‐II achieved status from the other three statuses. The EIPQ is recommended as the preferred instrument for making contrasts between or among identity statuses, whereas the EOM‐EIS‐II is recommended when the objective is to consider continuous measures of the identity statuses.