bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eigenfunctions and Hardy inequalities for a magnetic Schrödinger operator in ℝ2
Authors: Alziary Bénédicte , Fleckinger‐Pellé Jacqueline , Takáč Peter 
Published: August 2003

AbstractThe zero set {z∈ℝ2:ψ(z)=0} of an eigenfunction ψ of the Schrödinger operator ℒ︁V=(i∇+A)2+V on L2(ℝ2) with an Aharonov–Bohm‐type magnetic potential is investigated. It is shown that, for the first eigenvalue λ1 (the ground state energy), the following two statements are equivalent: (I) the magnetic flux through each singular point of the magnetic potential A is a half‐integer; and (II) a suitable eigenfunction ψ associated with λ1 (a ground state) may be chosen in such a way that the zero set of ψ is the union of a finite number of nodal lines (curves of class C2) which emanate from the singular points of the magnetic potential A and slit the two‐dimensional plane ℝ2. As an auxiliary result, a Hardy‐type inequality near the singular points of A is proved. The C2 differentiability of nodal lines is obtained from an asymptotic analysis combined with the implicit function theorem. Copyright © 2003 John Wiley & Sons, Ltd.
A new stereo‐analytical method for determination of removal blocks in discontinuous rock masses
Authors: Zhang Zixin , Kulatilake P. H. S. W. 
Published: August 2003

AbstractThe paper provides a new stereo‐analytical method, which is a combination of the stereographic method and analytical methods, to separate finite removable blocks from the infinite and tapered blocks in discontinuous rock masses. The methodology has applicability to both convex and concave blocks. Application of the methodology is illustrated through examples. Addition of this method to the existing block theory procedures available in the literature improves the capability of block theory in solving practical problems in rock engineering. Copyright © 2003 John Wiley & Sons, Ltd.
Network reliability assessment in a random environment
Authors: Özekici S. , Soyer R. 
Published: August 2003

AbstractIn this paper we consider networks that consist of components operating under a randomly changing common environment. Our work is motivated by power system networks that are subject to fluctuating weather conditions over time that affect the performance of the network. We develop a general setup for any network that is subject to such environment and present results for network reliability assessment under two repair scenarios. We also present Bayesian analysis of network failure data and illustrate how reliability predictions can be obtained for the network. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 574–591, 2003
Scheduling jobs with piecewise linear decreasing processing times
Authors: Cheng T.C. Edwin , Ding Qing , Kovalyov Mikhail Y. , Bachman Aleksander , Janiak Adam 
Published: August 2003

AbstractWe study the problems of scheduling a set of nonpreemptive jobs on a single or multiple machines without idle times where the processing time of a job is a piecewise linear nonincreasing function of its start time. The objectives are the minimization of makespan and minimization of total job completion time. The single machine problems are proved to be NP‐hard, and some properties of their optimal solutions are established. A pseudopolynomial time algorithm is constructed for makespan minimization. Several heuristics are derived for both total completion time and makespan minimization. Computational experiments are conducted to evaluate their efficiency. NP‐hardness proofs and polynomial time algorithms are presented for some special cases of the parallel machine problems. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 531–554, 2003
Improved multi‐level Newton solvers for fully coupled multi‐physics problems
Authors: Kim J. Y. , Aluru N. R. , Tortorelli D. A. 
Published: August 2003

AbstractAn algorithm is suggested to improve the efficiency of the multi‐level Newton method that is used to solve multi‐physics problems. It accounts for full coupling between the subsystems by using the direct differentiation method rather than error prone finite difference calculations and retains the advantage of greater flexibility over the tightly coupled approaches. Performance of the algorithm is demonstrated by solving a fluid–structure interaction problem. Copyright © 2003 John Wiley & Sons, Ltd.
A first prehistoric case of tuberculosis from Britain
Authors: Mays Simon , Taylor G. Michael 
Published: August 2003

AbstractA likely case of tuberculosis in an Iron Age human burial from Dorset, England is described. Osteological examination and biomolecular study support the diagnosis. A radiocarbon determination indicates a date range for the burial of BC 400–230. This case represents the earliest reported case of tuberculosis from Britain, and indicates that the disease was present here prior to the Roman invasion. Copyright © 2003 John Wiley & Sons, Ltd.
Osteological evidence for the Battles of Zürich, 1799: a glimpse into soldiery of the past
Authors: Meyer C. 
Published: August 2003

AbstractFour human skeletons probably could be attributed to people killed during the Battles of Zürich in 1799. Cranial and postcranial gunshot wounds are consistent with those made by black powder weapons using lead balls as ammunition. Additional finds include a probable case of Scheuermann's Disease and a pipe smoker's facet. Copyright © 2003 John Wiley & Sons, Ltd.
Polymeric liquid crystals: cholesteric superstructure from blends of hydroxypropylcellulose esters
Authors: Bianchi Estella , Marsano Enrico , Picasso Paolo , Matassini Lorenzo , Costa Camilla 
Published: August 2003

Abstractn‐Butyric, iso‐butyric, n‐valeric and iso‐valeric esters of hydroxypropylcellulose were synthesized. Their behaviors, in terms of cholesteric structure, glass (Tg) and anisotropic‐isotropic (Ti) transition temperatures are compared to results in the literature. A 6–8 month time period from sample preparation has no influence on the cholesteric phase characteristics. Six binary blends may be formed from the four esters. They show only a Tg value at each composition, which suggests a good miscibility among the components. However, positive deviation of linearity of Tg vs. composition varies from one pair to another. Analysis of the absorption curves in UV‐vis spectra show that three pairs form a single cholesteric helix containing both components while other three give a only nematic phase. Colors changing from red to violet are shown for blends of n‐butyric and iso‐butyric esters at different weight ratio. Copyright © 2003 John Wiley & Sons, Ltd.
Studies on thermal and morphological properties of 1,1‐bis(3‐methyl‐4‐cyanatophenyl)cyclohexane‐epoxy‐bismaleimide matrices
Authors: Dinakaran K. , Alagar M. 
Published: August 2003

AbstractA new cyanate ester monomer, 1,1‐bis(3‐methyl‐4‐cyanatophenyl)cyclohexane has been synthesized and characterized. Epoxy modified with 4, 8 and 12% (by weight) of cyanate ester were made using epoxy resin and 1,1‐bis(3‐methyl‐4‐cyanatophenyl)cyclohexane and cured by using diaminodiphenylmethane. The cyanate ester modified epoxy matrix systems were further modified with 4, 8 and 12% (by weight) of bismaleimide (N,N′‐bismaleimido‐4,4′‐diphenylmethane). The formation of oxazolidinone and isocyanurate during cure reaction of epoxy and cyanate ester blend was confirmed by IR spectral studies. Bismaleimide‐cyanate ester‐epoxy matrices were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and heat deflection temperature (HDT) analysis. Thermal studies indicate that the introduction of cyanate ester into epoxy resin improves the thermal degradation studies at the expense of glass transition temperature. Whereas the incorporation of bismaleimide into epoxy resin enhances the thermal properties according to its percentage content. However, the introduction of both cyanate ester and bismaleimide influences the thermal properties according to their percentage content. DSC thermogram of cyanate ester modified epoxy and bismaleimide modified epoxy show unimodel reaction exotherms. The thermal degradation temperature and heat distortion temperature of the cured bismaleimide modified epoxy and cyanate ester‐epoxy systems increased with increasing bismaleimide content. The morphology of the bismaleimide modified epoxy and cyanate ester‐epoxy systems were also studied by scanning electron microscopy. Copyright © 2003 John Wiley & Sons, Ltd.
The fabrication and characterization of poly(lactic acid) scaffolds for tissue engineering by improved solid–liquid phase separation
Authors: Tu Chifeng , Cai Qing , Yang Jian , Wan Yuqing , Bei Jianzhong , Wang Shenguo 
Published: August 2003

AbstractIn this article a new technique was developed to fabricate scaffolds with a unique microstructure by solid–liquid separation in combination with particulate‐leaching. Firstly, the effects of polymer concentration, quenching temperature on the porous morphology and the mechanical property of obtained scaffolds during solid–liquid separation have been investigated. Then, salt granules as porogen were introduced into the solid–liquid phase separation to produce the unique pore structure of the scaffold. The pore diameter of the scaffold could be controlled with the particulate size and the wall of pores possessed special microstructure, which enhanced the pore interconnectivity. The cell culture results confirmed that a good interconnectivity of the scaffold prepared by the improved solid–liquid separation was useful for nutrition transportation and cell proliferation. Copyright © 2003 John Wiley & Sons, Ltd.
Safe Schools/Healthy Students initiative: Pinellas County, Florida
Authors: Armstrong Kathleen Hague , Massey Oliver T. , Boroughs Michael , Bailey Ralph , LaJoie Diane 
Published: August 2003

AbstractThe Safe Schools/Healthy Students (SS/HS) Initiative in Pinellas County, FL, emerged as a part of a broader local effort to implement creative educational and mental health programs to support children and families. This initiative focused on capacity building, prevention, and intervention efforts and comprehensive evaluation to address the barriers to learning and enhance healthy development. This article describes Pinellas County's plan, and highlights the instrumental roles played by school psychologists, which included grant writing, program and resource coordination, clinical services, program evaluation, staff training, parent advocacy, and steering committee membership. Promising outcomes and generalization of these findings to other communities is also discussed. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 489–501, 2003.
The aspartimide problem in Fmoc‐based SPPS. Part II
Authors: Mergler M. , Dick F. , Sax B. , Stähelin C. , Vorherr T. 
Published: August 2003

AbstractThe sequence dependence of base‐catalysed aspartimide formation during Fmoc‐based SPPS was systematically studied employing the peptide models H‐Val‐Lys‐Asp‐Xaa‐Tyr‐Ile‐OH. The extent of formation of aspartimide and related by‐products was determined by RP‐HPLC. Considerable amounts of by‐products were formed in the case of Xaa = Asp(OtBu), Arg(Pbf), Asn(Mtt), Cys(Acm) and unprotected Thr. Aspartimide formation could be diminished by incorporation of Asp(OMpe) or by employing milder methods for Fmoc cleavage, e.g. hexamethyleneimine/N‐methylpyrrolidine/HOBt/NMP/DMSO 4 : 50 : 4 : 71 : 71 (v/v/w/v/v). Copyright © 2003 European Peptide Society and John Wiley & Sons, Ltd.
Remarks on the updated Hessian matrix methods
Authors: Bofill Josep Maria 
Published: August 2003

AbstractOptimizing a function with respect to a set of variables using the quasi‐Newton–Raphson method implies updating the Hessian matrix at each iteration. The Broyden–Fletcher–Goldfarb–Shanno update formula is used for minimization and the Murtagh–Sargent–Powell update formula for optimization of first‐order saddle points. Two new formulae are proposed to update the Hessian matrix. One of these formulae is derived using exponential weights and should be used to locate first‐order saddle points. The second formula is a modification of the TS–Broyden–Fletcher–Goldfarb–Shanno update and could used for both minimum and first‐order saddle point optimizations. These two update Hessian matrix formulae present a performance that is the same and in many cases better that the Broyden–Fletcher–Goldfarb–Shanno and Murtagh–Sargent–Powell formulae. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 94: 324–332, 2003
Testing a model of reasoned risk‐taking: governance, the experience of principals and agents, and global strategy in high‐technology IPO firms
Authors: Carpenter Mason A. , Pollock Timothy G. , Leary Myleen M. 
Published: August 2003

AbstractResearch on the governance of risky ventures, like the initial public offerings (IPOs) of high‐technology firms, has focused primarily on the relationship between governance mechanisms and firm performance. While such an emphasis is clearly important, it does little to shed light on potential relationships between governance and the strategies pursued by risky firms, nor does it take into account the complementary role of key stakeholders in affecting those strategies. To partially remedy this deficit we integrate agency and behavioral perspectives to develop a theory of ‘reasoned risk‐taking,’ whereby the nature of risks undertaken is a consequence of the interaction of governance mechanisms and stakeholder characteristics. We demonstrate our theory by predicting when corporate governance should be associated with strategic risk‐seeking beyond a firm's technical core—as seen in the degree to which it has expanded internationally. Surprisingly, even though venture capitalists (VC) are risk specialists, we find that technology‐based IPO firms are less likely (i.e., a negative relationship) to have extensive global sales when they are backed by a VC. In support of our reasoned risk‐taking theoretical framework, we find that VCs are indeed risk‐seeking when VC backing is complemented by the international experience of their board appointees, top management team (TMT) members, or both. IPO firms with significant insider ownership are similarly global risk‐seekers, and those effects are strongest with an internationally seasoned board and TMT at the helm. Copyright © 2003 John Wiley & Sons, Ltd.
Predicting a firm's forecasting ability: the roles of organizational illusion of control and organizational attention
Authors: Durand Rodolphe 
Published: August 2003

AbstractRecent research shows that forecasting ability is an organizational distinctive competence. We propose and test a model accounting for interfirm differences in forecasting ability. After controlling for reciprocal effects, we find that two principal firm‐level factors (i.e., organizational illusion of control and organizational attention) influence both bias and magnitude of errors in estimates. High organizational illusion of control increases positive forecast bias. As for organizational attention, higher relative investments in market information appear to reduce positive forecast bias and magnitude of errors; they also moderate forecast bias due to illusion of control. Finally, higher relative investments in employee capability increase both negative forecast bias and, unexpectedly, magnitude of errors for the majority of observed cases. Copyright © 2003 John Wiley & Sons, Ltd.
Profitability of small‐ and medium‐sized enterprises in high‐tech industries: the case of the biotechnology industry
Authors: Qian Gongming , Li Lee 
Published: August 2003

AbstractThis paper investigates the profitability determinants of small‐ and medium‐sized enterprises in high‐tech industries. Literature review suggests that innovator position, market awareness, niche operation, and internationalization should have positive impacts on SMTEs' profitability. However, the empirical results partially agree with, and partially dissent from, the propositions. Copyright © 2003 John Wiley & Sons, Ltd.
Developing end‐user tailorable Web applications using a compositional framework
Authors: Mejuev I 
Published: August 2003

AbstractSince Web‐based applications are typically required to accommodate a rapid development cycle and be adaptable to the needs of heterogeneous communities of users, the ability to continue evolving after deployment (tailoring) is regarded as a valuable property for any software accessible via a WWW‐browser interface. This article introduces a reusable compositional framework to support the development of end‐user‐tailorable applications for the Web. This framework defines the composition of tailorable applications with an object‐scripting technique, based on nested compositional markup specifications. Application tailorability is achieved through the use of a ‘visualizer’ pattern that allows decoupling of tailoring interfaces from primitive components and recomposing fragments of an application at runtime. The framework permits the application of multiple tailoring interfaces (visualizers) to an application instance, reusing tailoring interfaces across multiple application domains and allows for the evolution of visual techniques for carrying out tailoring throughout a project lifecycle. This article summarizes the experience accumulated while developing the proposed framework using the Java 2 platform and introduces two case studies that have been made on the development of remote monitoring applications in the domain of large‐scale control systems in high‐energy physics and interactive multimedia courseware for the Web. Copyright © 2003 John Wiley & Sons, Ltd.
Cellular localization of three vesicular glutamate transporter mRNAs and proteins in rat spinal cord and dorsal root ganglia
Authors: Oliveira Alexandre L.R. , Hydling Fredrik , Olsson Eric , Shi Tiejun , Edwards Robert H. , Fujiyama Fumino , Kaneko Takeshi , Hökfelt Tomas , Cullheim Staffan , Meister Björn 
Published: August 2003

AbstractGlutamate is transported into synaptic vesicles by vesicular glutamate transporter (VGLUT) proteins. Three different VGLUTs, VGLUT1, VGLUT2, and VGLUT3, have recently been characterized, and they are considered to represent the most specific marker so far for neurons using glutamate as transmitter. We analyzed the cellular localization of VGLUT1‐3 in the rat spinal cord and dorsal root ganglia (DRGs) in control rats and after dorsal rhizotomy. Using in situ hybridization, VGLUT1 mRNA containing neurons were shown in the dorsomedial part of the intermediate zone, whereas VGLUT2 mRNA‐expressing neurons were present in the entire intermediate zone, both populations most likely representing interneurons. VGLUT3 mRNA could not be detected in the spinal cord. In the ventral horn, a dense plexus of VGLUT1‐immunoreactive (ir) nerve terminals was present, with large varicosities abutting on presumed motoneurons. In the dorsal horn a similarly dense plexus was seen, except in laminae I and II. A very dense plexus of VGLUT2‐ir fibers was distributed in the entire gray matter of the spinal cord, with many fibers lying close to presumed motoneurons. Few VGLUT3‐ir fibers were distributed in the white and gray matter, including lamina IX. However, a dense VGLUT3‐ir plexus was seen in the sympathetic intermedio‐lateral column (IML). Multiple‐labeling immunohistochemistry revealed that the VGLUT1‐, VGLUT2‐, and VAChT‐containing varicosities in lamina IX all represent separate entities. There was no colocalization of VGLUT3 with VAChT or 5‐HT in varicose fibers of the ventral horn, but some VGLUT3‐ir fibers in the IML were 5‐HT‐positive. Lesioning of the dorsal roots resulted in an almost complete disappearance of VGLUT1‐ir fibers around motoneurons and a less pronounced decrease in the remaining gray matter, whereas the density of VGLUT2‐ and VAChT‐ir fibers appeared unaltered after lesion. Many VGLUT1‐ir neurons were observed in DRGs; they were almost all large and did not colocalize calcitonin gene‐related peptide (CGRP), and there was no overlap between these markers in fibers in the superficial dorsal horn. VGLUT2 was, at most, seen in a few DRG neurons. Taken together, these results suggest that the VGLUTs mRNAs are present in distinct subsets of neuronal populations at the spinal level. VGLUT1 is mainly present in primary afferents from large, CGRP‐negative DRG neurons, VGLUT2 has mainly a local origin, and VGLUT3 fibers probably have a supraspinal origin. Synapse 50:117–129, 2003. © 2003 Wiley‐Liss, Inc.
Serotonergic regulation of the GABAergic transmission in the rat basal ganglia
Authors: Di Cara Benjamin , Samuel Denise , Salin Pascal , Kerkerian‐Le Goff Lydia , Daszuta Annie 
Published: August 2003

AbstractThe GABAergic neurons represent a major neuronal population in the basal ganglia. Although alterations in serotonin (5‐HT) transmission are associated with neurodegenerative diseases involving these regions, the influence exerted by 5‐HT afferents on GABAergic populations remains poorly understood. Here, we examined the consequences of 5,7‐dihydroxytryptamine‐induced lesion of 5‐HT neurons on glutamic acid decarboxylase (GAD) activity, mRNA expression of the two isoforms of the enzyme, GAD65 and GAD67, GABA uptake, and extracellular GABA levels in the striatum. The 5‐HT depletion produced an increase in GAD activity without modifying GAD65 and GAD67 mRNA levels, suggesting that 5‐HT acts at the posttranscriptional level to regulate striatal GABA synthesis. No change in GAD activity was measured in the main striatal target structures, the globus pallidus and substantia nigra. Striatal GABA uptake and extracellular levels of GABA measured under basal conditions in freely moving rats were maintained in a normal range following 5‐HT deprivation. By contrast, depolarization‐induced increases in extracellular levels of GABA were larger in the striatum of 5‐HT‐deprived rats than in controls, which may be accounted for by an increase in a releasable pool of GABA due to increased synthesis rate. Together, these results suggest that 5‐HT afferents may exert a phasic inhibitory control on striatal GABA transmission. Therefore, a decrease in striatal 5‐HT transmission in disease states, such as Parkinson's disease, may contribute to pathological changes in striatal GABA neuron activity by increasing their reactivity to depolarizing stimuli. Synapse 50:144–150, 2003. © 2003 Wiley‐Liss, Inc.
Intrastriatal serotonin 5‐HT2 receptors mediate dopamine D1‐induced hyperlocomotion in 6‐hydroxydopamine‐lesioned rats
Authors: Bishop Christopher , Kamdar Dev P. , Walker Paul D. 
Published: August 2003

AbstractStriatal dopamine (DA) and serotonin (5‐HT) functions are altered following DA denervation. Previous research indicates that intrastriatal coadministration of D1 and 5‐HT2 receptor agonists synergistically increase locomotor behavior in DA‐depleted rats. In the present study, we examined whether striatal 5‐HT2 mechanisms also account for supersensitive D1‐mediated locomotor behavior following DA denervation. Adult male Sprague‐Dawley rats were subjected to bilateral striatal cannulation and then received either intracerebroventricular (i.c.v.) or intrastriatal 6‐hydroxydopamine (6‐OHDA; 200 μg or 20 μg/side, respectively). After at least 3 weeks, i.c.v.‐lesioned rats received intrastriatal infusions of the 5‐HT2 receptor antagonist ritanserin (2.0 μg/side) or its vehicle (DMSO) followed by systemic SKF 82958, a D1 agonist (1.0 mg/kg, i.p.) and locomotor activity was monitored. In another experiment, intrastriatal sham and 6‐OHDA‐lesioned rats received bilateral intrastriatal infusions of ritanserin (2.0 μg/side) or its vehicle (DMSO) followed by intrastriatal infusions of SKF 82958 (5.0 μg/side) or vehicle (0.9% saline). Rats with DA loss demonstrated supersensitive locomotor responses to both systemic and intrastriatal SKF 82958. Ritanserin pretreatment blunted systemic SKF 82958‐induced hyperlocomotion and returned intrastriatal D1‐mediated hyperactivity to sham lesion levels. The results of this study suggest that striatal 5‐HT2 receptors contribute to D1‐mediated hyperkinesias resulting from DA loss and suggest a pharmacological target for the alleviation of dyskinesia that can develop with continued DA replacement therapy. Synapse 50:164–170, 2003. © 2003 Wiley‐Liss, Inc.