bluuebunny/crossref_metadata_2025_split huggingface dataset:
Therapeutic stimulation of denervated muscles: The influence of pattern
Authors: Ashley Zoe , Sutherland Hazel , Russold Michael F. , Lanmüller Hermann , Mayr Winfried , Jarvis Jonathan C. , Salmons Stanley 
Published: June 2008

AbstractMuscular atrophy due to denervation can be substantially reversed by direct electrical stimulation. Some muscle properties are, however, resistant to change. Using a rabbit model of established denervation atrophy, we investigated whether the extent of restoration would vary with the stimulation protocol. Five patterns, delivering 24,000–480,000 impulses/day, were applied for 6 or 10 weeks. The wet weight, cross‐sectional area, tetanic tension, shortening velocity, and power of denervated muscles subjected to stimulation all increased significantly. The fibers were larger and more closely packed and there was no evidence of necrosis. There was a small increase in excitability. Isometric twitch kinetics remained slow and fatigue resistance did not improve. The actual pattern of stimulation had no influence on any of these findings. The results, interpreted in the context of ultrastructural changes and an ongoing clinical study, reaffirm the clinical value of introducing stimulation during the initial non‐degenerative phase. They indicate that there would be little therapeutic benefit in adopting regimes more energetically demanding than those in current use, and that the focus should now shift to protocols that represent the least intrusion into activities of daily living. © 2008 Wiley Periodicals, Inc. Muscle Nerve 38: 875–886, 2008
Myotonic dystrophy type 1 coexisting with myasthenia gravis and thymoma
Authors: Feyma Timothy , Carter Gregory T. , Weiss Michael D. 
Published: June 2008

AbstractMyotonic dystrophy type 1 (DM1) is an autosomal‐dominant multisystemic disorder that may rarely be associated with benign and malignant neoplasms. Cases of both thymoma and myasthenia gravis in association with DM1 are extremely rare. A literature review revealed only three prior reports. We present a 51‐year‐old man with a family history of DM1 and fluctuating diplopia and ptosis, who was found to have acetylcholine receptor–binding antibodies, thymoma, and a clinical presentation compatible with ocular myasthenia gravis as well as positive genetic testing for DM1. Needle electromyographic (EMG) study demonstrated diffuse runs of myotonic discharges in multiple muscles, consistent with the diagnosis of DM1. Single‐fiber EMG showed both increased jitter and blocking. Due to somatic instability, which has been shown previously in DM1, the myotonin protein kinase (DMPK) gene appears to act as a tumor suppressor. Therefore, abnormal CTG repeat expansions in the gene could lead to the development of thymoma and myasthenia gravis. Muscle Nerve 38: 916–920, 2008
Calibrated quantitative ultrasound imaging of skeletal muscle using backscatter analysis
Authors: Zaidman Craig M. , Holland Mark R. , Anderson Christian C. , Pestronk Alan 
Published: June 2008

AbstractWe evaluated the ability of an ultrasound method, which can characterize cardiac muscle pathology and has reliability across different imaging systems, to obtain calibrated quantitative estimates of backscatter of skeletal muscle. Our procedure utilized a tissue‐mimicking phantom to establish a linear relationship between ultrasound grayscale and backscatter levels. We studied skeletal muscles of 82 adults: 45 controls and 37 patients with hereditary myopathies. We found that skeletal muscle ultrasound backscatter levels varied with probe orientation, age, and muscle contraction and pathology. Reliability was greater with the probe in longitudinal compared with transverse planes. Backscatter levels were higher in those >40 years of age, in muscle extension than flexion, and in myopathic patients than controls. Calibrated measurements of muscle backscatter have sensitivity and specificity in identifying and reliably measuring levels of skeletal muscle pathology. Muscle Nerve 38: 893–898, 2008
Intranervous immunoglobulin deposits: An underestimated mechanism of neuropathy
Authors: Vallat Jean‐Michel , Magy Laurent , Richard Laurence , Piaser Martine , Sindou Philippe , Calvo Judith , Ghorab Karima , Cros Didier 
Published: June 2008

AbstractThere are several pathogenic mechanisms of peripheral nerve involvement in patients with monoclonal dysglobulinemia. Intranervous proliferation of malignant cells, immunoglobulin, or amyloid deposits in the endoneurial space can only be determined by examination of nerve biopsy specimens. We present clinical, electrophysiological, and histological data from seven patients whose polyneuropathy was induced by immunoglobulin deposits in the endoneurial space. As these lesions cannot be demonstrated on clinical and electrophysiological grounds, the indication for nerve biopsy derives from careful analysis of each patient presenting with a polyneuropathy and a monoclonal dysglobulinemia. To visualize and clearly characterize these deposits, electron microscopic examination is indispensable. Immunocytochemical methods using both light and electron microscopy for ultrastructural analysis are of great value. Demonstration of endoneurial immunoglobulin deposits may have major therapeutic consequences. Indeed, identification of these deposits prompted the use of aggressive treatment, which was quite effective in five of our seven patients. Muscle Nerve 38: 904–911, 2008
Axonal neuropathy due to myelin protein zero mutation misdiagnosed as amyloid neuropathy
Authors: Briani Chiara , Adami Fausto , Cavallaro Tiziana , Taioli Federica , Ferrari Sergio , Fabrizi Gianmaria 
Published: June 2008

AbstractIn up to 50% of chronic idiopathic axonal neuropathies, an underlying diagnosis may be identified, including hereditary neuropathy. Charcot–Marie–Tooth disease (CMT) is clinically and genetically heterogeneous. Several mutations in the myelin protein zero (MPZ) gene have been associated with different CMT phenotypes, including classical demyelinating CMT1B and the axonal form of the disease. Primary amyloidosis, a rare disease where the amyloid is formed by the N‐terminal portion of a monoclonal immunoglobulin light chain, may be complicated by polyneuropathy. We report a patient who was incorrectly diagnosed with amyloid neuropathy, but was found to have axonal CMT1B only after sural nerve biopsy ruled out an acquired amyloid neuropathy. Muscle Nerve 38: 921–923, 2008
IBLU decompositions based on Padé approximants
Authors: Buzdin A. , Logashenko D. , Wittum G. 
Published: June 2008

AbstractIn this paper, we introduce a new class of frequency‐filtering IBLU decompositions that use continued‐fraction approximation for the diagonal blocks. This technique allows us to construct efficient frequency‐filtering preconditioners for discretizations of elliptic partial differential equations on domains with non‐trivial geometries. We prove theoretically for a class of model problems that the application of the proposed preconditioners leads to a convergence rate of up to 1−O(h1/4) of the CG iteration. Copyright © 2008 John Wiley & Sons, Ltd.
Using the complex polynomial method with Mathematica to model problems involving the Laplace and Poisson equations
Authors: Poler A.C. , Bohannon A.W. , Schowalter S.J. , Hromadka T.V. 
Published: June 2008

AbstractThe complex polynomial method variant of the well‐known complex variable boundary element method (CVBEM) is reexamined in its utility in solving Partial Differential Equations (PDE) of the Poisson and Laplace type. Because the CVBEM was recently extended to three and higher dimensions, the use of complex polynomials to solve higher dimension PDE becomes apparent and therefore the advantages afforded by the use of complex polynomials can be brought to focus on higher dimension problems. Because complex polynomials involve use of computational algorithms that require high accuracy in numerical precision, including the solution of fully populated nonsymmetric matrices, the computer program Mathematica is evaluated for use as the underlying computational engine. Furthermore, Mathematica is evaluated for its internal high‐accuracy computational features and algorithms, including ease of program setup. In this research, the new program is found to provide at least a 5‐fold increase in complex polynomial degree utilization (from degree 10 to degree 50), with computational speed less than was involved in the original degree 10 approximation of Hromadka and Guymon [ASCE J Hydraulic Eng 110 (1984), 329–339], and with exceptional computational accuracy and reporting features. The Mathematica program is quite small and is provided to the reader as freeware and can be obtained from the first author. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
Chebyshev‐Legendre spectral method for solving the two‐dimensional vorticity equations with homogeneous Dirichlet conditions
Authors: Wu Hua , Ma Heping , Li Huiyuan 
Published: June 2008

AbstractThe Chebyshev‐Legendre spectral method for the two‐dimensional vorticity equations is considered. The Legendre Galerkin Chebyshev collocation method is used with the Chebyshev‐Gauss collocation points. The numerical analysis results under the L2‐norm for the Chebyshev‐Legendre method of one‐dimensional case are generalized into that of the two‐dimensional case. The stability and optimal order convergence of the method are proved. Numerical results are given. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
Effect of the various coupling agents on the mechanical and physical properties of thermoplastic‐bagasse fiber composites
Authors: Youssef H.A. , Ismail M.R. , Ali M.A.M. , Zahran A.H. 
Published: June 2008

AbstractVarious types of bonding agents have been tried with blends of bagasse fibers and some thermoplastics such as low‐density polyethylene (LDPE), high‐density polyethylene (HDPE), polystyrene (PS), polypropylene (PP), and polyvinyl chloride (PVC). These bonding agents are, namely, pentaerythritol tetracrylate (PETA), 1,6 hexandiol diacrylate (HDA), and dicumyl peroxide (DCP). In addition, a traditional coupling agents 3‐aminopropyltrimethoxy silane (AMPS) and di‐aminopropyltrimetoxy silane (DAMPS) were included for comparison. Electron beam (EB) irradiation is applied only for LDPE and HDPE at 40 and 10 kGy, respectively, before mixing with bagasse fibers. The data obtained reveal that incorporation of bonding agents remarkably increases the mechanical properties for all samples under investigation; the maximum improvement is observed in LDPE followed by HDPE, PP, PS, and PVC composites. Also, the physical properties enhanced but not at the same degree as mechanical properties. Among the tested bonding agents, it was found that PETA, DCP followed by DAMPS have highest efficiency in LDPE, whereas in case of HDPE, EB radiation was higher than PETA followed by DCP. PETA was superior in case of PS composites. Furthermore, PETA and HDA experienced higher efficiency than DAMPS and AMPS in case of PP and PVC composites. Comparison between the properties of thermoplastic composites and medium density fiberboard (MDF) reveals that most of the properties of thermoplastics composites are better than MDF. However, modulus of rupture of MDF was found to be slightly higher than thermoplastics except for PVC composite. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Finite element analysis for thermoforming process of continuous fiber reinforced thermoplastic composites
Authors: Abadi Mohammad Tahaye 
Published: June 2008

AbstractAn implicit finite element method is presented to model thermoforming process of thermoplastic materials reinforced with unidirectional fibers or woven fabric. The composite materials are regarded as a homogenized anisotropic viscous fluid restricted by kinematical constrains of material incompressibility and fiber inextensibility at the forming temperature. Unlike previous numerical approaches considering quasi‐static assumptions during each increment, a high order polynomial expression is used to define continuous displacement and velocity fields. The material parameters are also updated during each increment to determine the displacement and velocity fields satisfying the equilibrium equations as well as the kinematical constrains both in the rate and total deformation forms. An iterative solution method is presented to solve the finite element formulation. The numerical results are compared with analytical solutions and the results of previous implicit finite element approaches to demonstrate the computational accuracy and efficiency of the present method. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Effect of frequency upon fatigue strength of a short glass fiber reinforced polyamide 6: A superposition method based on cyclic creep parameters
Authors: Bernasconi Andrea , Kulin Robb M. 
Published: June 2008

AbstractThe fatigue behavior of a conditioned short glass‐fiber reinforced polyamide 6 was studied and the effect of the cyclic frequency investigated. Load controlled fatigue tests were performed, and the strains and surface temperature of specimens were recorded continuously. The number of cycles to failure was found to be dependent upon cyclic creep rate, as is typical for short glass fiber reinforced polyamides in the conditioned state. A strong reduction of fatigue strength was observed for increasing cyclic load frequency. This was mainly related to the specimen temperature increase due to hysteretic self heating and its effect on the cyclic creep speed. A frequency superposition method is proposed, expressing the relationship between temperature rise, applied stress, and cyclic creep speed in terms of a parameter derived from the Larson–Miller steady creep parameter. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
SiC dispersed polysulphide epoxy resin based functionally graded material
Authors: Hashmi S.A.R. , Dwivedi U.K. 
Published: June 2008

AbstractGravity and centrifugal castings are considered the most economical and attractive processes for making functionally graded materials (FGMs). The control on property change in radial direction in aforesaid methods is mainly based on the initial concentration, viscosity, time, centrifugal force, particle size, and density difference in dispersed and dispersion medium as per Stoke's law. The modified Stoke's law in the form of HD model that takes into account the intrinsic changes in viscosity those occur during the polymerization of resins, was used for determining changes in concentration with time at different locations of test samples for SiC dispersed poly sulphide epoxy resin FGM. The experiments as well as simulation were conducted under gravity as well as centrifugal force. The simulated results are in good agreement with those ofexperiments. The process parameters, initial concentration, etc., can be selected for a desired concentration profile of FGM. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Study on microstructure, rheological, and mechanical properties of cellulose short fiber reinforced TPVs based on EPDM/PP
Authors: Goharpey F. , Mirzadeh A. , Sheikh A. , Nazockdast H. , Katbab A.A. 
Published: June 2008

AbstractThe morphology, rheology, and mechanical properties of the dynamically vulcanized thermoplastic elastomer based on EPDM/PP (60/40, w:w) containing 5, 10, and 20% of cellulose short fiber were studied. From the results it was found that addition of 5% of cellulose fiber has no significant effect on the maximum torque associated with the dynamic vulcanization stage, while higher concentration of fibers decreased the maximum torque. These results were explained in terms of influence of cellulose fibers on the extent of agglomeration formed between the cured rubber particles. The results of tensile test performed on the samples showed that incorporation of 5% of cellulose fibers into the sample has an increasing effect on elongation at break with no appreciable change in tensile behavior. However increasing the cellulose fibers content of the sample to 20% had a remarkable change in tensile properties of the sample resulting in a toughened plastic type behavior. The melt elasticity of the sample containing 5% of cellulose fibers particularly at low shear rate range was found to be lower than that of the sample without fibers indicating the role of fibers in weakening of cured rubber particle agglomeration. This was supported with the results of the relaxation time distribution H(λ) and scanning electron microscopy of the samples. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Preparation and characterization of nylon 6/organoclay nanocomposite filament fibers
Authors: Kim Kap Jin , Lee Jong Soon , Prabu Arun Anand , Kim Taek Hyun 
Published: June 2008

AbstractA series of nylon 6 (NY6)/organoclay nanocomposites were prepared via in situ polymerization of ε‐caprolactam in the presence of 1,2‐aminododecanoic acid‐intercalated montmorillonite (ADA‐MMT) organoclay (1–5 wt%) using 6‐aminocaproic acid as polymerization catalyst. The extent of organoclay dispersion in NY6 matrix was analyzed using WAXD and SEM measurements. DSC studies revealed marginal shift in melting and melt‐crystallization peaks toward lower temperature with increasing clay content. Melt viscosity studies for NY6/ADA‐MMT exhibited higher shear‐thinning behavior than neat NY6 probably due to the slip between NY6 matrix and exfoliated organoclay platelets during shear flow. The prepared nanocomposites were melt‐spun and studied for their property improvements against varying clay content, draw ratios, and annealing conditions. Birefringence and sonic velocity values increased initially at lower draw ratios (≤2.5) due to increased orientation of molecular chains along the drawing direction but saturated at higher draw ratio (3.0) for all the samples. At the same draw ratio; compared to neat NY6, NY6/organoclay fibers showed increased chain orientation along the drawing direction which can be attributed to the “tethering effect” of organoclay on NY6 matrix. The initial modulus and stress at break were sensitive to factors such as draw ratio, clay content, and annealing conditions. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Interfacial adhesion and molecular diffusion in melt lamination of wood sawdust/ebonite NR and EPDM
Authors: Yamsaengsung W. , Sombatsompop N. 
Published: June 2008

AbstractAdhesion mechanisms and peel strengths of wood/ebonite NR‐EPDM laminates were investigated. Three different chemical coupling agents: namely; N‐(β aminoethyl)‐γ‐aminopropyl‐triethoxysilane (AAS), 3‐methacryloxypropyl trimethoxysilane (ACS), and Bis‐(3‐triethoxylpropyl) tetrasulfan (Si69) were introduced into the wood/NR composites to enhance an interaction between wood sawdust (SD) particles and NR molecules, and to improve the adhesion strength between the SD/NR and EPDM layers. The quantitative evidences were given to explain the changes in the adhesion or peel strengths of the SD/NR‐EPDM laminates through scanning electron microscopy with energy dispersive X‐ray analysis (SEM‐EDS). The experimental results indicated that the suitable cure time and cure temperature for SD/NR‐EPDM melt‐laminates were the tc90 of SD/NR composites and 140°C, respectively. The Si69 coupling agent was found to be the most effective coupling agent as compared with AAS and ACS coupling agents. The Si69 of 0.5 wt% was recommended for the optimizations of the tensile modulus of the SD/NR composites and the peel strength of the SD/NR‐EPDM laminates. The diffusion level between the SD/NR and EPDM layers could be quantitatively substantiated by determining the sulfur content transfer from the SD/NR layer to the EPDM layer. The diffusion and entanglement of molecular chains from the SD/NR to the EPDM layer initiated the co‐crosslinking reaction which played an important role on the changes in the interfacial strength in the SD/NR‐EPDM melt‐laminates. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Rheology and flow behavior of suspensions of nanosized plate‐like particles in polyester resins at the startup of shear flows; Experimental and modeling
Authors: Rajabian Mahmoud , Beheshty Mohammad H. 
Published: June 2008

AbstractApplications of organoclays to polymer resins are potentially of great technical interest. This research targets preparation and characterization of nanocomposites of organoclays in an unsaturated polyester resin (UP). The nanocomposites with two distinct dispersion levels were compounded in a complex multisteps mixing process at three concentrations and subsequently their microstructures were characterized by XRD. The solution‐state rheological properties of layered silicate/UP were measured in the start‐up of steady state in the simple shear mode and analyzed based on our observations of internal structure of nanoparticles dispersion. Strong shear thinning behavior caused by increasing particle alignment induced by the shear field was observed for the suspensions. Effects of nanoparticles loadings and shearing on transient viscosity of the UP resin were examined. The experimental results show that increasing shear time in nanosuspension preparation steps and hence improvements of nanoplate dispersion in the polyester resin give rise to viscosity of the suspensions. A theoretical analysis of the motion of rigid ellipsoidal particles in a Newtonian fluid based on the thermodynamic approach and Jeffery's analysis of the motion of ellipsoid particles with an interaction term was developed to determine the orientation state of disc‐shape layers and then, the expression for the extra stress tensor was calculated to predict transient viscosity and normal stress differences. It is found that the thin oblate particles have significant orientation preference in the shearing direction. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Curing behavior and properties of epoxy nanocomposites with amine functionalized multiwall carbon nanotubes
Authors: Choi Woo Jin , Powell Robert L. , Kim Dae Su 
Published: June 2008

AbstractCarbon nanotubes (CNTs) with reactive functional groups such as amines would affect not only properties but also curing behavior of an epoxy nanocomposite system comprising them. Therefore, in this study, an amine functionalization of multiwall CNTs (MWNTs) was carried out via treating pristine MWNTs (PMWNT) with 4‐aminobenzoic acid in polyphosphoric acid. The functionalization was confirmed by Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Epoxy nanocomposites comprising the PMWNT or functionalized MWNTs (FMWNT) were prepared and their curing behavior and properties were investigated. Differential scanning calorimetry (DSC) was used to obtain experimental conversion data for curing kinetic analysis. The FMWNT accelerated the curing rate of the nanocomposite system. The functionalization induced strong interfacial bonding between the epoxy matrix and the MWNTs, and resulted in considerable improvements in the properties of the nanocomposites. The SEM image showed strong interfacial bonding between the epoxy matrix and the FMWNT. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers