bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrical impedance myography in the detection of radiculopathy
Authors: Rutkove Seward B. , Esper Gregory J. , Lee Kyungmouk S. , Aaron Ronald , Shiffman Carl A. 
Published: June 2005

AbstractElectrical impedance myography (EIM) is a new bioimpedance‐based technique for neuromuscular disease assessment. Past work has focused on EIM in the evaluation of diffuse diseases (such as myopathy). In this study, the method's most basic form, linear‐EIM, was used for the assessment of restricted radiculopathic disease. Ten normal subjects and 10 patients with unilateral cervical or lumbosacral radiculopathy, diagnosed by electromyography and clinical criteria, were enrolled. Linear‐EIM was performed bilaterally on all individuals, and comparisons with the major outcome variable, θavg, were made. In normal subjects, side‐to‐side differences in θavg averaged 0.64% and were no greater than 15.9% in magnitude. In the 10 patients with radiculopathy, θavgwas consistently lower in the affected extremity, with a mean side‐to‐side difference of 15.3%, but ranging as low as 72.3%; there was a tendency for muscles with more prominent chronic neurogenic change to show greater relative reductions in θavg. These findings support the potential utility of EIM in assessment of localized neuromuscular disease. Muscle Nerve, 2005
Three‐dimensional topography of the motor endplates of the rat gastrocnemius muscle
Authors: Prodanov Dimiter , Thil Marie‐Anne , Marani Enrico , Delbeke Jean , Holsheimer Jan 
Published: June 2005

AbstractSpatial distribution of motor endplates affects the shape of the electrical activity recorded from muscle. In order to provide information for realistic models of action potential propagation within muscles, we assembled three‐dimensional maps of the motor endplates of the rat medial gastrocnemius (MGM) and lateral gastrocnemius (MGL) muscles. The maps were assembled from histological cross sections stained for acetylcholinesterase activity. Within MGL, the motor endplates formed three columns along its longitudinal axis. Within MGM, the motor endplates were arranged in a leaf‐like body that shifted obliquely from proximal to distal. As inferred from the proximo‐distal distribution of the cross‐sectional projection area, the majority of the motor endplates were concentrated in the middle of MGL and in the distal third of MGM. Regions of maximal motor endplate concentration are considered most suitable for injections of neuroactive substances, such as neuronal tracers. The assembled maps of the gastrocnemius muscles can be used as guides for such injections within the motor endplate zones. Muscle Nerve, 2005
Project scheduling under competition
Authors: Averbakh Igor , Lebedev Vasilij 
Published: June 2005

AbstractWe introduce and investigate the problem of scheduling activities of a project by a firm that competes with another firm (the competitor) that has to perform the same project. The profit that the firm gets from each activity depends on whether the firm finishes the activity before or after its competitor. The objective is to maximize the guaranteed (worst‐case) profit. We assume that both the firm and the competitor can perform only one activity at a time. We perform a detailed complexity analysis of the problem, and consider problems with and without precedence constraints, with and without delay of the competitor, with general and equal processing times of activities. For polynomially solvable cases (which include, for example, all the considered problems without delay of the competitor), we present easily implementable and intuitive rules that allow us to obtain optimal schedules in linear or almost linear time. For some NP‐hard cases, we present pseudopolynomial algorithms and fast heuristics with worst‐case approximation guarantees. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005.
A superfast solver for real symmetric Toeplitz systems using real trigonometric transformations
Authors: Codevico G. , Heinig G. , Van Barel M. 
Published: June 2005

AbstractA new superfast O(n log2 n) complexity direct solver for real symmetric Toeplitz systems is presented. The algorithm is based on 1. the reduction to symmetric right‐hand sides, 2. a polynomial interpretation in terms of Chebyshev polynomials, 3. an inversion formula involving real trigonometric transformations and 4. an interpretation of the equations as a tangential interpolation problem. The tangential interpolation problem is solved via a divide and conquer strategy and fast DCT. Copyright © 2005 John Wiley & Sons, Ltd.
Matrix recursive expressions of the DFT of even and odd complex sequences
Authors: Notarnicola Filippo 
Published: June 2005

AbstractThe discrete Fourier transform of even complex sequences involves, in matrix formulation, a cosine matrix and, in the same way, the discrete Fourier transform of odd complex sequences is related with a sine matrix. Using structural characteristics of the two matrices, whose order is half the length of the symmetric input data, some recursive expressions of them will be constructed.Unlike the previous classical forms of the discrete Fourier transform of an even or odd real vector, the recursive terms in the matrix expressions derived here only involve the same cosine and sine matrices, with halved order. That is, it is shown that, as for the FFT of a general complex sequence, a divide and conquer approach can also be used to compute the DFT of even or odd sequences. The recursion is closed in the family of the sine and cosine matrices used to describe the DFT of even and odd sequences and no other kind of sine or cosine based matrices are required in recursive terms.Although the obtained results give a new theoretical view on the problem of computing the DFT of even and odd complex sequences, these are not of immediate practical use since the computational cost is higher than other currently employed algorithms. Copyright © 2005 John Wiley & Sons, Ltd.
Central diabetes insipidus: Is it Langerhans cell histiocytosis of the pituitary stalk? A diagnostic pitfall
Authors: Prosch Helmut , Grois Nicole , Bökkerink Jos , Prayer Daniela , Leuschner Ivo , Minkov Milen , Gadner Helmut 
Published: June 2005

AbstractCentral diabetes insipidus (CDI) is a rare disorder that may be caused by a variety of diseases. In pediatric and adolescent patients the most common causes for CDI are Langerhans cell histiocytosis (LCH) and germinoma. To avoid a potentially hazardous biopsy of the hypothalamic pituitary region it is recommended to evaluate patients with CDI carefully to identify potential extracranial lesions. Since LCH is the most common systemic disease that may cause CDI, special focus is paid to the identification of LCH lesions. We report on a 9½ year old girl who presented with central diabetes insipidus and a thickening of the pituitary stalk on magnetic resonance imaging. Diagnostic workup revealed a history of recurrent ear infections and a compressed 6th thoracic vertebral body on radiographs. Based on these findings LCH was anticipated. Upon growth of the pituitary stalk lesion the patient was treated with LCH standard chemotherapy. After an initial shrinkage of the lesion, a further growth of the pituitary stalk lesion was observed and the tumor was resected. Histopathology revealed germinoma. This case underscores the importance of a istopathologically proven diagnosis in patients with HPR tumors before the initiation of a specific therapy, even if the clinical findings are highly suggestive. © 2005 Wiley‐Liss, Inc.
Synthesis, properties and pyrolysis of siloxane‐ and imide‐modified epoxy resin cured with siloxane‐containing dianhydride
Authors: Li Hsun‐Tien , Chuang Hsun‐Ren , Wang Ming‐Wei , Lin Mu‐Shih 
Published: June 2005

AbstractHydrosilylation of nadic anhydride with tetramethyl disiloxane yielded 5,5′‐(1,1,3,3‐tetramethyl disiloxane‐1,3‐diyl)‐bis‐norborane‐2,3‐dicarboxylic anhydride (I), which further reacted with 4‐aminophenol to give N,N′‐bis(4‐hydroxyphenyl)‐5,5′‐bis‐(1,1,3,3‐tetramethyl disiloxane‐1,3‐diyl)‐bis‐norborane‐2,3‐dicarboximide (II). Epoxidation of II with excess epichlorohydrin formed a siloxane‐ and imide‐modified epoxy oligomer (ie diglycidyl ether of N,N′‐bis(4‐hydroxyphenyl)‐5,5′‐bis(1,1,3,3‐tetramethyl disiloxane‐1,3‐diyl)‐bis‐norborane‐2,3‐dicarboximide) (III). Equivalent ratios of III/I of 1/1 and 1/0.8 were prepared and cured to produce crosslinked materials. Thermal mechanical and dynamic mechanical properties were investigated by TMA and DMA, respectively. It was noted that each of these two materials showed a glass transition temperature (Tg) higher than 160 °C with moderate moduli. The thermal degradation kinetics was studied with dynamic thermogravimetric analysis (TGA) and the estimated apparent activation energies were 111.4 kJ mol−1 (in N2), 117.1 kJ mol−1 (in air) for III/I = 1/0.8, and 149.2 kJ mol−1 (in N2), 147.6 kJ mol−1 (in air) for III/I = 1/1. The white flaky residue of the TGA char was confirmed to be silicon dioxide, which formed a barrier at the surface of the polymer matrix and, in part, accounted for the unique heat resistance of this material. Copyright © 2005 Society of Chemical Industry
UV‐Vis spectroscopic study of the hydrophilic and solvatochromic 4‐[2,6‐diphenyl‐4‐(pyridin‐4‐yl)pyridinium‐1‐yl]‐2,6‐bis(pyridin‐3‐yl)phenolate betaine dye in aqueous tetra‐n‐butylammonium bromide
Authors: Herodes Koit , Leito Ivo , Koppel Juta , Reichardt Christian , Koppel Ilmar A. 
Published: June 2005

AbstractThe solvent influence on the recently synthesized hydrophilic and negatively solvatochromic 4‐[2,6‐diphenyl‐4‐(pyridin‐4‐yl)pyridinium‐1‐yl]‐2,6‐bis(pyridin‐3‐yl)phenolate betaine dye [ET(8) dye] dissolved in binary water–tetra‐n‐butylammonium bromide mixtures was studied by UV–Vis spectroscopy and compared with analogous measurements of the standard ET(30) betaine dye [2,6‐diphenyl‐4‐(2,4,6‐triphenylpyridinium‐1‐yl)phenolate]. A preferential solvation model was applied to the data obtained. The ET(8) betaine dye can be applied for the determination of ET(30) values for aqueous media. However, the nonlinear nature of the relationship has to be taken into account if accurate results are desired. Copyright © 2005 John Wiley & Sons, Ltd.
Effect of hydrophobic side‐chains on the solvation of imidazolium salts
Authors: Headley Allan D. , Kotti S. R. S. Saibabu , Nam Jaewook , Li Kunyu 
Published: June 2005

AbstractThe chemical shifts of the aromatic hydrogens of 12 symmetrical imidazolium salts were determined in different deuterated solvents. Based on the magnitude of the chemical shift change for the hydrogens of the imidazolium ion in the various solvents, relationships were developed to determine the relative solute/solvent interactions for these compounds. Owing to different degrees of interactions involving the aromatic hydrogens of the imidazolium cations and anions, there is a variation in the interaction of the hydrogens with the solvent molecules. The intimate interaction that exists between the hydrogens of the imidazolium cation and the BF anion results in the BF salts being less solvated compared with salts containing BF and SbF anions. For imidazolium salts that contain C2H5, C4H9 and C8H17 side‐chains bonded in the 1 and 3 positions, the interaction between H2 and the solvents was observed to be greater than for imidazolium salts with C16H33 substituents. On the other hand, for imidazolium salts that have C16H33 substituents the interaction between H2 and the solvents is similar to that for H4 and H5. Copyright © 2005 John Wiley & Sons, Ltd.
Synthesis, photophysics, structure‐tunable photoluminescence, and electrochemical properties of soluble poly(p‐phenylenevinylene)‐based polymers with adjacent 1,3,4‐oxadiazoles in the backbone
Authors: Mikroyannidis John A. , Hlídková Helena , Výprachtický Drahomír , Cimrová Věra 
Published: June 2005

AbstractThree new poly(p‐phenylenevinylene)‐based polymers containing two 1,3,4‐oxadiazole moieties in the main chain per repeat unit were synthesized by Heck coupling. A single, double, or triple bond was introduced between the oxadiazoles to provide a means for modifying the polymer properties. The polymers were readily soluble in common organic solvents and showed Tg values lower than 50 °C. The color of the emissive light in both the solid state and the solution could be tuned by a change in the nature of the bond between the oxadiazole rings. The polymers emitted ultraviolet‐green light in solution with a photoluminescence (PL) emission maximum at 345–483 nm and blue‐green light at 458–542 nm in thin films. The PL quantum yields in solution were 0.36–0.43. The electrochemical properties are affected by the nature of the bond between the oxadiazoles as well. In polymers with a single bond between the oxadiazoles, a lower ionization potential was observed than in polymers with a double or triple bond. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3079–3090, 2005
Synthesis, characterization, and metal complexes of polyacetylenes with pendant 2,2′‐bipyridyl groups
Authors: Vicente José , Gil‐Rubio Juan , Barquero Natalia 
Published: June 2005

Abstract5‐Ethynyl‐2,2′‐bipyridine (1; bpyC≡CH) polymerized in the presence of catalytic amounts of [RhF(COD)(PPh3)] or [Rh(μ‐OH)(COD)]2 (COD = 1,5‐cyclooctadiene) in 74–91% yields. In contrast, [Rh(μ‐X)(NBD)]2 (X = Cl or OMe; NBD = norbornadiene) did not catalyze the polymerization of 1 or gave low yields of the polymer. The obtained polymer, poly(5‐ethynyl‐2,2′‐bipyridine) [2; (bpyCCH)n], was highly stereoregular with a predominant cis–transoidal geometry. Random copolyacetylenes containing the 2,2′‐bipyridyl group with improved solubility in organic solvents were obtained by the treatment of a mixture of 1 and phenylacetylene (3) or 1‐ethynyl‐4‐n‐pentyl‐benzene with catalytic amounts of [RhF(COD)(PPh3)]. A block copolymer of 1 and 3 was prepared by the addition of 1 to a poly(phenylacetylene) containing a living end. The reaction of 2 with [Mo(CO)6] produced an insoluble polymer containing [Mo(CO)4(bpy)] groups, whereas with [RuCl2(bpy)2] or [Ru(bpy)2(CH3COCH3)2](CF3SO3)2, it gave soluble metal–polymer complexes containing [Ru(bpy)3]2+ groups. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43:3167–3177, 2005
Surface segregation in polymer blends and interpolymer complexes with increasing hydrogen bonding interactions
Authors: Liu Shiyong , Chan Chi‐Ming , Weng Lu‐Tao , Jiang Ming 
Published: June 2005

AbstractThe evolution of surface composition in polymer blends and interpolymer complexes was studied using X‐ray photoelectron spectroscopy (XPS) and Time‐of‐Flight secondary ion mass spectroscopy (ToF‐SIMS). For immiscible and miscible poly(styrene‐co‐4‐vinyl phenol)/poly(styrene‐co‐4‐vinyl pyridine) (STVPh/STVPy) blends, surface enrichment by the lower surface energy component STVPh was always observed. Increasing VPh contents in STVPh from 0 to 16 mol % spans the transition from immiscible to miscible blends; the differences in surface free energies between STVPh and STVPy decreased, but surface enrichment of STVPh continued to increase. This is due to the strong hydrogen bonded self‐association of STVPh, which dominates over the immiscibility to miscibility transition in controlling the surface composition. In the immiscible and miscible blends, decreasing the molecular weights of STVPy, which decreased the surface free energy of STVPy, systematically reduced surface enrichment by STVPh. For STVPh/STVPy complexes formed at VPh contents higher than 21 mol %, surface enrichment of STVPh is barely detectable. STVPh and STVPy form a new supramolecular species. Interpolymer complexation is now the decisive factor controlling the surface composition, dominating over the surface free energy differences; the effect of STVPy molecular weight variation on the surface composition is also negligible for the interpolymer complexes. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1924–1930, 2005
Isothermal crystallization kinetics of PP in PP/Mg(OH)2 composites
Authors: Yin Jun , Wang Shaohui , Zhang Yong , Zhang Yinxi 
Published: June 2005

AbstractThe crystallization and melting behavior of PP/Mg(OH)2 composites was investigated, and the crystallization kinetic parameters and thermal characteristics were investigated according to the Avrami method. Optical polarizing microscope (POM) analysis suggested that the presence of Mg(OH)2 particles gave rise to an increase in the number of nuclei and a decrease in PP spherulitic size. The Avrami exponent n of the PP and composites increased with increasing crystallization temperature, and markedly deceased with the addition of low Mg(OH)2 content. A significant increase in crystallization kinetic constant, and a decrease in crystallization half time of PP were observed in the presence of Mg(OH)2 particles, indicating a heterogeneous nucleating effect of Mg(OH)2 upon crystallization of PP. The melting temperature and equilibrium melting temperature of PP in the composites decreased with increasing the Mg(OH)2 content, which is directly related to the size of the PP crystals. The difference of PP melting enthalpies in the PP and composites demonstrated that the presence of Mg(OH)2 can effectively enhance the crystalline of PP. The crystallization thermodynamics of PP and composites were studied according to the Hoffman theory. Surface free energy of PP chain folding for crystallization of PP/Mg(OH)2 composites was lower than that of PP, confirming the heterogeneous nucleation effect of Mg(OH)2. However, the evaluation of the nucleation activation energy of PP suggested the presence of a large amount of Mg(OH)2 particles in the PP matrix reduced the mobility of PP segments and restricted the development of PP nucleation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1914–1923, 2005
Structure and properties of the δ‐form and mesophase of syndiotactic polystyrene membranes prepared from different organic solvents
Authors: Sivakumar Muthusamy , Mahesh K.P.O. , Yamamoto Yusuke , Yoshimizu Hiroaki , Tsujita Yoshiharu 
Published: June 2005

AbstractSyndiotactic polystyrene (sPS) membranes were prepared with different organic solvent systems and compared to get the information about the δ‐form complexing behavior of sPS. Further, the guest molecules included in the clathrate δ form of sPS are removed by stepwise extraction method. The conformational changes during the TTGG helical formation of sPS/organic solvent systems have been identified by FTIR spectroscopy, and it was concluded that the TTGG helices were constructed in regular sequences, which depends on the nature of the respective solvents. The TTGG content in the mesophase is found to be increased by removing the guest molecules. The structural changes of sPS/organic solvent systems have been characterized by WAXD analysis. Moreover, the different clathrate structures were found and showed the different crystalline reflections in the WAXD profiles, which are significantly changed with the kind of guest solvent included in sPS. The content of solvents in the clathrated sPS and the desorption temperatures were determined by thermal analysis. The resulted mesophase of sPS membrane contains the nanoporous molecular cavities that depend on the size of the guest molecule. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1873–1880, 2005
Electrospinning of polystyrene/poly(2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylene vinylene) blends
Authors: Wutticharoenmongkol Patcharaporn , Supaphol Pitt , Srikhirin Toemsak , Kerdcharoen Teerakiat , Osotchan Tanakorn 
Published: June 2005

AbstractUltrafine polystyrene (PS)/poly(2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylene vinylene) (MEH‐PPV) fibers were successfully prepared by electrospinning of PS/MEH‐PPV solutions in chloroform, 1,2‐dichloroethane, and tetrahydrofuran (THF). Three concentrations of the solutions were prepared: 8.5, 16, and 23.5% (w/v), with the compositional weight ratios between PS and MEH‐PPV being 7.5:1, 15:1, and 22.5:1, respectively. Smooth fibers only observed from 23.5% (w/v) PS/MEH‐PPV solution in chloroform. Improvement in the electrospinnability of 8.5% (w/v) PS/MEH‐PPV solution in chloroform was achieved by addition of an organic salt, pyridinium formate (PF), or by addition of a minor solvent with a high dielectric constant value. The average diameters of the as‐spun PS/MEH‐PPV fibers were between 0.30 and 5.11 μm. Last, photoluminescence of 8.5% (w/v) solutions of PS/MEH‐PPV in a mixed solvent system of chloroform and 1,2‐dichloroethane of various volumetric compositions and the resulting as‐spun fibers was investigated and compared. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1881–1891, 2005
Polypropylene/organoclay nanocomposites compatibilized with hydroxyl‐functional polypropylenes
Authors: Ristolainen Noora , Vainio Ulla , Paavola Santeri , Torkkeli Mika , Serimaa Ritva , Seppälä Jukka 
Published: June 2005

AbstractThe properties of polypropylene composites can be tailored through the use of nanoclay fillers. The effectiveness of a metallocene‐catalyzed hydroxyl‐functional polypropylene in the compatibilization of polypropylene layered nanosilicate composites was studied, and the results were compared with those for a commercial maleic anhydride functionalized polypropylene. Polypropylene/organoclay nanocomposites were prepared by melt blending, and two polypropylene/compatibilizer/organoclay ratios, 90/5/5 and 70/20/10, were characterized. The organomodification of the clay was carried out with octadecylamine and N‐methylundecenylamine. The structure of the layered silicate was studied by transmission electron microscopy, wide‐angle X‐ray scattering, and small‐angle X‐ray scattering. The fracture surfaces of the composites and thus the efficiency of the compatibilizers to penetrate the galleries of the organoclays were characterized by scanning electron microscopy, and the melt viscosity was studied by stress‐controlled rotational rheometry. The nanostructure was observed with both alkyl amines used for intercalation. The fillers facilitated the processability of all the composites, consisting of equal amounts of compatibilizer and organoclay filler and, in some of the composites, containing twice as much compatibilizer as organoclay filler. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1892–1903, 2005