bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of transcranial magnetic stimulation on voluntary activation in patients with quadriceps weakness
Authors: Urbach Dietmar , Berth Alexander , Awiszus Friedemann 
Published: June 2005

AbstractJoint disease causes weakness and wasting of adjacent muscles, in part because of inability to fully activate these muscles voluntarily. Previous findings suggest that transcranial magnetic stimulation (TMS) paired with muscle contractions enhances maximal voluntary contraction force (MVC) in healthy subjects by improving voluntary activation (VA). The aim of the present study was to evaluate whether such an effect is also present in subjects suffering from diminished muscle force due to decreased VA. Three single TMS over resting motor threshold were applied in 10 patients with a mean age of 62 years after total‐knee arthroplasty either during MVC or during muscle relaxation (control experiment) in a blinded randomized crossover study. MVC and VA were determined using a twitch‐interpolation technique at 1, 15, 30, and 60 min after stimulation. There was a significant effect of TMS on MVC if applied in synchrony with muscle contraction, and this persisted for at least 60 min beyond stimulation. In patients suffering from joint disease, TMS might make physiotherapy more effective. Muscle Nerve, 2005
Pain ratings at the thresholds are necessary for interpretation of quantitative sensory testing
Authors: Kelly Kiesa Getz , Cook Thomas , Backonja Misha‐Miroslav 
Published: June 2005

AbstractPublished databases of quantitative sensory testing (QST) for sensory thresholds provide a means for detecting deficits of the thermonociceptive sensory nervous system. These databases, however, do not assist in the assessment of neuropathic pain, which is characterized by pain or hyperalgesia, or both. We utilized the method of levels for innocuous thermal stimuli, warm and cool, and the method of limits for noxious thermal stimuli, hot pain and cold pain, to determine QST thresholds. Stimuli were applied to distal and proximal sites in the upper and lower limbs of 50 healthy volunteers, ranging in age from 19 to 59 years. Thresholds for innocuous and noxious stimuli in this study were similar to previously published results. The mean pain rating across all sites at thresholds for noxious heat and cold stimuli was 4.10, as rated on a 0–10 numeric scale. Suggestions are provided for combining threshold information for innocuous and noxious stimuli and related pain ratings for the evaluation of sensory nervous system function and, specifically, neuropathic pain. © 2005 Wiley Periodicals, Inc. Muscle Nerve, 2005
Hypercholesterolemia as a risk factor for idiopathic carpal tunnel syndrome
Authors: Nakamichi Ken‐Ichi , Tachibana Shintaro 
Published: June 2005

AbstractIn idiopathic carpal tunnel syndrome (CTS), the median nerve is enlarged within the carpal tunnel due to intraneural connective tissue proliferation. Because hypercholesterolemia, especially increase in low‐density lipoprotein (LDL), has been associated with fibrogenesis, we investigated the association of median nerve cross‐sectional area and prevalence of idiopathic CTS with serum lipid measurements in middle‐aged patients and controls. We found that nerve area and prevalence of CTS were correlated with serum LDL levels. Thus, high LDL levels in middle age are a risk factor for idiopathic CTS, suggesting that the LDL‐correlated median nerve enlargement increases the volume of the carpal tunnel contents. Muscle Nerve, 2005
Minimum principle and related numerical scheme for simulating initial flow and subsequent propagation of liquefied ground
Authors: Montassar Sami , de Buhan Patrick 
Published: June 2005

AbstractThe problem of predicting the evolution of liquefied ground, modelled as a viscoplastic material, is addressed by combining a minimum principle for the velocity field, which characterizes such an evolution, and a time step integration procedure. Two different numerical schemes are then presented for the finite element implementation of this minimum principle, namely, the regularization technique and the decomposition‐co‐ordination method by augmented Lagrangian. The second method, which proves more accurate and efficient than the first, is finally applied to simulate the incipient flow failure and subsequent spreading of a liquefied soil embankment subject to gravity. The strong influence of liquefied soil residual shear strength on reducing the maximum amplitude of the ground displacement is particularly emphasized in such an analysis. Copyright © 2005 John Wiley & Sons, Ltd.
Modelling chemo‐hydro‐mechanical behaviour of unsaturated clays: a feasibility study
Authors: Liu Z. , Boukpeti N. , Li X. , Collin F. , Radu J.‐P. , Hueckel T. , Charlier R. 
Published: June 2005

AbstractEffective capabilities of combined chemo‐elasto‐plastic and unsaturated soil models to simulate chemo‐hydro‐mechanical (CHM) behaviour of clays are examined in numerical simulations through selected boundary value problems. The objective is to investigate the feasibility of approaching such complex material behaviour numerically by combining two existing models. The chemo‐mechanical effects are described using the concept of chemical softening consisting of reduction of the pre‐consolidation pressure proposed originally by Hueckel (Can. Geotech. J. 1992; 29:1071–1086; Int. J. Numer. Anal. Methods Geomech. 1997; 21:43–72). An additional chemical softening mechanism is considered, consisting in a decrease of cohesion with an increase in contaminant concentration. The influence of partial saturation on the constitutive behaviour is modelled following Barcelona basic model (BBM) formulation (Géotech. 1990; 40(3):405–430; Can. Geotech. J. 1992; 29:1013–1032).The equilibrium equations combined with the CHM constitutive relations, and the governing equations for flow of fluids and contaminant transport, are solved numerically using finite element. The emphasis is laid on understanding the role that the individual chemical effects such as chemo‐elastic swelling, or chemo‐plastic consolidation, or finally, chemical loss of cohesion have in the overall response of the soil mass. The numerical problems analysed concern the chemical effects in response to wetting of a clay specimen with an organic liquid in rigid wall consolidometer, during biaxial loading up to failure, and in response to fresh water influx during tunnel excavation in swelling clay. Copyright © 2005 John Wiley & Sons, Ltd.
A viscoplastic model including anisotropic damage for the time dependent behaviour of rock
Authors: Pellet F. , Hajdu A. , Deleruyelle F. , Besnus F. 
Published: June 2005

AbstractThis paper presents a new constitutive model for the time dependent mechanical behaviour of rock which takes into account both viscoplastic behaviour and evolution of damage with respect to time. This model is built by associating a viscoplastic constitutive law to the damage theory. The main characteristics of this model are the account of a viscoplastic volumetric strain (i.e. contractancy and dilatancy) as well as the anisotropy of damage. The latter is described by a second rank tensor. Using this model, it is possible to predict delayed rupture by determining time to failure, in creep tests for example. The identification of the model parameters is based on experiments such as creep tests, relaxation tests and quasi‐static tests. The physical meaning of these parameters is discussed and comparisons with lab tests are presented. The ability of the model to reproduce the delayed failure observed in tertiary creep is demonstrated as well as the sensitivity of the mechanical response to the rate of loading. The model could be used to simulate the evolution of the excavated damage zone around underground openings. Copyright © 2005 John Wiley & Sons, Ltd.
Scattering of elastic wave by a partially sealed cylindrical shell embedded in poroelastic medium
Authors: Gan‐Bin Liu , Kang‐He Xie , Hai‐lin Yao 
Published: June 2005

AbstractScattering of an elastic wave by a cylindrical shell embedded in poroelastic medium is investigated theoretically with the assumption that the shell material is also a porous elastic medium. The porous medium is modellized via Biot's theory and the scattering by cylindrical shell is expressed by the definition of scattering matrix. The normal mode expansion technique is employed for analysing the scattering field, and the asymptotic solutions of displacements, stresses and pore pressure are derived. Two limiting cases‐scattering by a poroelastic cylinder in Biot medium and a elastic cylindrical shell in elastic medium are obtained from the general solutions. The dispersion curves of displacement amplitude at the interface of shell and medium is compared with the case of elastic shell. The scattering amplitude associated with the fast, slow and transverse waves are identified by numerical simulation. Furthermore, the influence of the poroelastic property of shell material on scattering amplitude is analysed. Copyright © 2005 John Wiley & Sons, Ltd.
Compatibilization of polystyrene/poly(butyl methacrylate)/poly[(ethylene glycol) dimethacrylate] blends via concentrated emulsion polymerization
Authors: Du Zhongjie , Zhang Chen , Li Hangquan 
Published: June 2005

AbstractTwo concentrated emulsions in water containing styrene and butyl methacrylate (BMA) as dispersed phases were prepared. Each of them contained a small amount of an amphiphilic macromonomer, poly[(ethylene glycol) dimethacrylate] (PEGD), in the continuous phase. The two concentrated emulsions were partially polymerized at 50 °C until conversions of about 22.5 % were reached. They were then mixed mechanically and the mixture was subjected to complete polymerization. During the latter polymerization, homopolymers of styrene and BMA and copolymers of the two were generated. The copolymers, particularly the crosslinked structures, which were formed through copolymerization of PEGD with styrene and BMA at the interface of the latexes, provided compatibilizers for the homopolymers. This blend of homopolymers, copolymers and crosslinked structures possessed excellent toughness and processability. The blends were characterized by their gel content, and by X‐ray photoelectron spectroscopy, rheometric testing, dynamic mechanical thermal analysis, transmission electron microscopy and impact strength measurements. Copyright © 2005 Society of Chemical Industry
De novo sequence analysis of N‐terminal sulfonated peptides after in‐gel guanidination
Authors: Sergeant Kjell , Samyn Bart , Debyser Griet , Van Beeumen Jozef 
Published: June 2005

AbstractHere we report a novel approach in which gel‐separated proteins are guanidinated in‐gel prior to enzymatic cleavage. In contrast to previously described techniques, this procedure allows the extracted tryptic peptides to be N‐terminal sulfonated without any further sample purification. The derivatized peptides were subsequently fragmented using a matrix‐assisted laser desorption/ionization time of flight/time of flight instrument. The approach facilitates the de novo sequence analysis and allows obtaining longer stretches of amino acid sequence information. We demonstrate that the obtained information can be used to identify proteins using a sequence similarity search algorithm. The technique was compared to the standard peptide mass fingerprint approach, applied either in‐gel or in solution, using a number of sodium dodecyl sulfate‐polyacrylamide gel electrophoresis separated model proteins. Finally, the new protocol was applied on a proteomic study of two‐dimensional PAGE separated proteins from Shewanella oneidensis. More than 50 proteins from this organism were identified using sub‐picomol quantities of protein, and peptide sequences of up to 20 amino acid residues in length have been determined.
A “de‐streaking” method for two‐dimensional electrophoresis using the reducing agent tris(2‐carboxyethyl)‐phosphine hydrochloride and alkylating agent vinylpyridine
Authors: Bai Fengju , Liu Sheng , Witzmann Frank A. 
Published: June 2005

AbstractSee original http://dx.doi.org/10.1002/pmic.200501291
Directly copolymerized poly(arylene sulfide sulfone) disulfonated copolymers for PEM‐based fuel cell systems. I. Synthesis and characterization
Authors: Wiles K. B. , Wang F. , McGrath J. E. 
Published: June 2005

AbstractDirect aromatic nucleophilic substitution polycondensations of disodium 3,3′‐disulfonate‐4,4′‐difluorodiphenylsulfone (SDFDPS), 4,4′‐difluorodiphenylsulfone (DFDPS) (or their chlorinated analogs), and 4,4′‐thiobisbenzenethiol in the presence of potassium carbonate were investigated. Electrophilic aromatic substitution was employed to synthesize the SDFDPS comonomer in high yields and purity. High molecular weight disulfonated copolymers were easily obtained using the SDFDPS monomers, but in general, slower rates and a lower molecular weight copolymer were obtained using the analogous chlorinated monomers. Tough and ductile membranes were solution cast from N,N‐dimethylacetamide for both series of copolymers. The degrees of disulfonation (20–50%) were controlled by varying the ratio of disulfonated to unsulfonated comonomers. Precise control of the ionic concentration, well‐defined ionic locations, and enhanced stability due to the deactivated position of the –SO3H group are some of the suggested advantages of direct copolymerization of sulfonated monomers. Further publications will discuss additional characteristics of these copolymers that have the same repeat unit, but different molecular weights, using methanol permeability, water uptake, protonic conductivity, and dynamic mechanical analysis. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2964‐2976, 2005
Preparation of poly(ethylene oxide)‐block‐poly(isoprene) by nitroxide‐mediated free radical polymerization from PEO macroinitiators
Authors: Wegrzyn Jakub K. , Stephan Tim , Lau Ryan , Grubbs Robert B. 
Published: June 2005

AbstractAmphiphilic poly(ethylene oxide)‐block‐poly(isoprene) (PEO‐b‐PI) diblock copolymers were prepared by nitroxide‐mediated polymerization of isoprene from alkoxyamine‐terminal poly(ethylene oxide) (PEO). PEO monomethyl ether (Mn ≈ 5200 g/mol) was functionalized by esterification with 2‐bromopropionyl bromide with subsequent copper‐mediated replacement of the terminal bromine with 2,2,5‐trimethyl‐4‐phenyl‐3‐azahexane‐3‐nitroxide. The resulting PEO‐alkoxyamine macroinitiator was used to initiate polymerization of isoprene in bulk and in solution at 125 °C to yield PEO‐b‐PI block copolymers with narrow molecular weight distributions (Mw/Mn ≤ 1.1). Polymerizations were first order in isoprene through 35% conversion. Micellar aggregates of PEO‐b‐PI in aqueous solution were crosslinked by treatment with a water‐soluble redox initiating system, and persistent micellar structures were observed in the dry state by AFM. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2977–2984, 2005
Synthesis and characterization of organosoluble ditrifluoromethylated aromatic polyimides
Authors: Liu Baijun , Hu Wei , Matsumoto Toshihiko , Jiang Zhenhua , Ando Shinji 
Published: June 2005

AbstractTwo novel diamine monomers, 1,4‐bis (4‐aminophenoxy)‐2‐[(3′,5′‐ditrifluoromethyl)phenyl]benzene and 1,4‐bis [2′‐cyano‐3′(4″‐amino phenoxy)phenoxy]‐2‐[(3′,5′‐ditrifluoromethyl)phenyl] benzene, were synthesized from (3,5‐ditrifluoromethyl)phenylhydroquinone. A series of ditrifluoromethylated aromatic polyimides derived from the diamines were prepared through a typical two‐step polymerization method. These polyimides had a high thermal stability, and the temperatures at 10% weight loss were above 507 °C in nitrogen. Most of the polymers showed good solubility in anhydrated 1‐methyl‐2‐pyrrolidone, N,N‐dimethylacetamide, N,N‐dimethylformamide, chloroform, and tetrahydrofuran at room temperature. All the polymers formed transparent, strong, and flexible films with tensile strengths of 63.6–95.8 MPa, elongations at break of 5–10%, and Young's moduli of 2.38–2.96 GPa. The dielectric constants estimated from the average refractive indices are 2.69–2.89. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3018–3029, 2005
Synthesis of poly(isobutyl‐co‐2,2,2‐trifluoroethyl methacrylate) with 5,10,15,20‐tetraphenylporphinato platinum(II) moiety as an oxygen‐sensing dye for pressure‐sensitive paint
Authors: Obata Makoto , Tanaka Yurie , Araki Naoko , Hirohara Shiho , Yano Shigenobu , Mitsuo Kazunori , Asai Keisuke , Harada Masafumi , Kakuchi Toyoji , Ohtsuki Chikara 
Published: June 2005

AbstractPressure‐sensitive paint (PSP), which consists of luminescent molecules embedded in an oxygen‐permeable polymer, has been developed for use in wind‐tunnel experiments. To improve the PSP technique, a novel luminescent methacrylate monomer, 5‐[4‐(2‐methacryloyloxyethoxycarbonyl)phenyl]‐10,15,20‐triphenylporphinato platinum(II), was synthesized and copolymerized with isobutyl methacrylate and 2,2,2‐trifluoroethyl methacrylate to produce a dye‐pendant copolymer (2). The introduction of 5,10,15,20‐tetraphenylporphinato platinum(II) (PtTPP) dye into 2 was confirmed by ultraviolet–visible spectroscopy and extended X‐ray absorption fine structure measurements. The extent of PtTPP dye incorporation in 2 was proportional to the molar fraction of the PtTPP‐pendant methacrylate monomer in the feed. The oxygen‐sensing property of 2 was compared with that of a PSP consisting of PtTPP dye embedded in poly(isobutyl‐co‐2,2,2‐trifluoroethyl methacrylate). Although the simple mixture of PtTPP and poly(isobutyl‐co‐2,2,2‐trifluoroethyl methacrylate) showed a marked deviation from a single Stern–Volmer relation, novel copolymer 2 gave a highly linear Stern–Volmer plot. This was unequivocal evidence of dye conjugation on the oxygen‐sensing polymer film. © 2005Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2997–3006, 2005
Pt‐catalyzed chemical modification of α,ω‐bis(hydrido)polydimethylsiloxanes and copoly(methylhydridosiloxane/dimethylsiloxane) with vinylheptaphenylcyclotetrasiloxane
Authors: Gädda Thomas M. , Weber William P. 
Published: June 2005

AbstractPt‐catalyzed hydrosilylation between vinylheptaphenylcyclotetrasiloxane and a series of α,ω‐bis(hydrido)polydimethylsiloxanes and copoly(methylhydridosiloxane/dimethylsiloxane) was used to prepare chemically modified materials. These modified polymers were characterized by IR, UV, and 1H, 13C, and 29Si NMR spectroscopy and gel permeation chromatography (GPC). The molecular weights, determined by GPC, UV, and NMR end‐group analysis, showed the anticipated increases. The thermal properties of the polymers were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The crystallinity, determined by DSC, was either reduced or completely eliminated for the modified polymers. The thermal stabilities, measured in both air and nitrogen by TGA, were slightly higher than the thermal stability of α,ω‐bis(trimethylsiloxy)polydimethylsiloxane. Significantly increased bulk viscosities were observed for all the modified polymers. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3007‐3017, 2005
Preparation and characterization of the chromatographic properties of ethylene glycol dimethacrylate/divinylbenzene polymeric microspheres
Authors: Maciejewska Małgorzata , Osypiuk Joanna , Gawdzik Barbara 
Published: June 2005

AbstractThe preparation of porous ethylene glycol dimethacrylate/divinylbenzene polymeric microspheres is presented. These materials were investigated as column packings for high‐performance liquid chromatography. Their porous structures in both the dry and wet states were also studied. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3049–3058, 2005
Synthesis of carbohydrate‐linked poly(polyoxometalate) poly(amido)amine dendrimers
Authors: Morgan Joel R. , Cloninger Mary J. 
Published: June 2005

AbstractMannose‐functionalized and ethoxyethanol‐functionalized poly(amido)amine dendrimers bound multiple vanadate‐substituted polyoxotungstate Wells–Dawson‐type polyoxometalates (POMs). Dendrimers incorporating 10–30 POMs were characterized with NMR, transmission electron microscopy, and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry techniques. The number of metal clusters per dendrimer molecule varied according to the dendrimer generation and the nature of the surface functional groups. Efforts aimed at using the poly(polyoxometalate) dendrimers as oxidation catalysts are also described. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3059–3066, 2005
Kinetically controlled phase transitions in liquid‐crystalline polymers. II. Isothermal degradation of ferroelectric switching in a chiral side‐chain polysiloxane during slow smectic B phase formation
Authors: Kozlovsky Mikhail , Skarp Kent 
Published: June 2005

AbstractThe kinetics of phase transformations in a chiral siloxane polymer has been studied with an Avrami analysis of the differential scanning calorimetry data. Ferroelectric switching has been measured as a function of the driving voltage and temperature. The evolution of the switching at a constant temperature has been studied within the temperature range of the kinetically governed smectic C*/smectic B phase transition. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1779–1784, 2005
Viscoelastic characterization of polymers using instrumented indentation. II. Dynamic testing*
Authors: White C. C. , VanLandingham M. R. , Drzal P. L. , Chang N.‐K. , Chang S.‐H. 
Published: June 2005

AbstractDynamic nanoindentation was performed on a cured epoxy, a poly(methyl methacrylate) (PMMA), and two poly(dimethyl siloxane) (PDMS) samples of different crosslink densities. These samples were used to compare dynamic nanoindentation with classical rheological measurements on polymeric samples in the glassy and rubbery plateau regions. Excellent agreement between bulk rheological data and dynamic nanoindentation data was observed for the two glassy materials (epoxy and PMMA) and the less compliant PDMS sample. More divergent results were observed for the more compliant PDMS sample. The theoretical foundation and historical development of the working equations for these two types of instrumentation are presented and discussed. The major difference between nanoindentation and the more classical rheological results is in the treatment of the instrument–sample interface. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1812–1824, 2005
Morphology and elastic modulus of novel poly[oligo(ethylene glycol) diacrylate]‐montmorillonite nanocomposites
Authors: Chen Biqiong , Bowden Allen A. , Greenwell H. Chris , Boulet Pascal , Coveney Peter V. , Whiting Andrew , Evans Julian R. G. 
Published: June 2005

AbstractNovel thermosetting poly[oligo(ethylene glycol) diacrylate]‐sodium montmorillonite nanocomposites containing a range of clay volume fractions were prepared by an in situ polymerization method. X‐ray diffraction showed that the basal plane spacing of the clay was increased to approximately 1.7 nm regardless of clay volume fraction. Transmission electron microscopy confirmed the basal spacing and intercalated structure. The elastic moduli of the composites were measured using ultrasonic pulse‐echo equipment. The results show that the Young's modulus and shear modulus increase with nominal clay volume fraction up to 0.22, and are in good agreement with the well‐established Christensen method and derived Hashin–Shtrikman bounds for conventional composites provided that the true volume fraction of clay reinforcement filler is calculated. At low clay volume fractions, the composites were transparent. When the nominal clay volume fraction was further increased, cracks and porous surfaces appeared, as observed by scanning electron microscopy. These defects decreased the elastic modulus, indicating an upper limit for clay additions in this preparation route. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1785–1793, 2005