bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extensor truncal dystonia: Successful treatment with botulinum toxin injections
Authors: Comella Cynthia L. , Shannon Kathleen M. , Jaglin Jeana 
Published: May 2005

AbstractPatients with truncal extension dystonia, manifested by involuntary back arching, often associated with pain and severe motor disability, have not consistently responded to pharmacologic agents. We evaluated 4 women and 1 man (mean age, 41.8 years; dystonia duration, 9.8 years) with severe idiopathic (2 patients) or tardive (3 patients) truncal and cervical dystonia. Using electromyographic guidance, we injected botulinum toxin into the paravertebral muscles of the lumbar region in four to six sites using 25–50 U per site. We reevaluated patients 2–4 weeks after injection. The mean dose of botulinum toxin into back muscles was 210 U (range, 150–300 U). By blinded videotape evaluation, objective improvement was found in three patients with a mean truncal dystonia score improving by 37%. Patient evaluation showed improvement in movement ranging from 20–80% (mean, 46%) after botulinum toxin. In all patients with pain as a result of dystonia, there was substantial improvement. None of the patients worsened and no adverse effects occurred. Botulinum toxin injections offer a potent new treatment for truncal dystonia.
Inhibition of levodopa effects by internal pallidal stimulation
Authors: Krack Paul , Pollak Pierre , Limousin Patricia , Hoffmann Dominique , Benazzouz Abdelhamid , Benabid Alim‐Louis 
Published: May 2005

AbstractWe report three patients with bilateral GPi stimulation for stage 4 Parkinson's disease (PD) with severe levodopa‐induced dyskinesias (LID). In all three it was possible to completely inhibit LID using high‐stimulation parameters. Parallel to complete inhibition of LID, an inhibition of the anti‐akinetic effect of levodopa was observed, whereas, at the same time, rigidity was markedly improved. GPi stimulation is adaptable over time, and stimulation parameters have to be programmed according to off‐and on‐period motor symptoms. The main interest of stimulation is the possibility of finding a compromise between LID alleviation in on‐phase without loss of the beneficial motor effects and improvement in parkinsonism in off‐phase. In some patients, residual dyskinesias have to be accepted so as not to aggravate on‐period motor symptoms by a presumed overinhibition of basal ganglia outflow.
Dysfunction of Ib (Autogenic) spinal inhibition in patients with progressive supranuclear palsy
Authors: Fine Edward J. , Hallett Mark , Litvan Irene , Tresser Nancy , Katz David 
Published: May 2005

AbstractWe compared the activity of Ib spinal interneurons in five patients with progressive supranuclear palsy (PSP) with six age‐matched control subjects. Stimulation of the medial gastrocnemius nerve at motor threshold intensity activated Ib afferents that in turn inhibit H reflexes from the soleus muscle. Maximum inhibition occurred at interstimulus intervals of 6 and 8 ms for both control subjects and PSP patients and was significantly greater in the PSP patients. Increased Ib activity of PSP patients may be caused by loss of inhibition of Ib interneurons through degeneration of the medullary reticulospinal pathway. The corticospinal pathways, unopposed by the medullary reticulospinal tract, may excessively activate Ib internurons.
Neurosurgical intervention for cervical disk disease in dystonic cerebral palsy
Authors: Pollak Lea , Schiffer Juana , Klein Colin , Mirovsky Yigal , Copeliovich Lionel , Rabey José Martin 
Published: May 2005

AbstractWe report five young patients with athetoid‐spastic cerebral palsy who had deteriorated neurologically. Magnetic resonance imaging (MRI) was used to investigate suspected compressive cervical spine lesion. Cervical spondylosis with disk protrusions was found in all patients. Four patients under went surgery by an anterior approach with insertion of a bone graft resulting in substantial clinical improvement. The other patient, diagnosed 8 years after onset of symptoms, was treated conservatively. The availability of MRI makes early recognition of cervical cord compression possible, allowing effective surgical intervention in this special group of patients.
DNA fragmentation in human substantia nigra: Apoptosis or perimortem effect?
Authors: Kingsbury Ann E. , David Mardsen C. , Foster Oliver J. F. 
Published: May 2005

AbstractDNA fragmentation was examined in situ in flashfrozen human postmortem midbrain as a marker for programmed cell death. A large series of cases comprising 16 pathologically confirmed idiopathic Parkinson's disease (IPD) cases, 14 control cases without brain pathology, and a group of 6 patients with other parkinsonian movement disorders were examined using TdT‐mediated dUTP‐biotin 3′ end‐labeling histology. Labeling of neurons and glia was seen in the substantia nigra of control and IPD cases and in other movement disorder cases. Labeled nuclei were seen in melanized nigral neurons; apoptotic bodies were also found but were more commonly associated with nigral glia. In the control group, labeling of neurons and glia was strongly associated with poor agonal status, assessed by tissue pH, a marker for antemortem hypoxia. The mean tissue pH of the control group with neuronal labeling was 6.28 (SEM .057), which was significantly different from that of the unlabeled group 6.55 (SEM .055). Mean tissue pH for all cases was 6.38. There was no association of nigral neuronal labeling with poor agonal status in the IPD cases, which showed labeling throughout the range of pH values. However, extranigral labeling, seen in the mesencephalon, red nucleus, superior colliculus, rostral pons, and periaqueductal gray matter, in all three subject groups was associated with tissue pH values of less than 6.3.These findings suggest that DNA fragmentation is influenced by antemortem hypoxia and that apoptosis‐like changes seen in the postmortem nigra may parallel those seen in experimental ischemia in the animal brain. The likely influence of perimortem factors on these changes indicates that results from postmortem studies of apoptotic cell death in neurodegenerative disease should be treated with caution and underlines the importance of determining postmortem markers for agonal status in human brain.
Curing theory on the Aai–Bbj type polycondensation (III). The gelation range
Authors: Zheng Fu‐an , Tang Xin‐yi 
Published: May 2005

AbstractBy means of the gelation equation containing both inter‐ and intramolecular reaction parameters obtained by the authors, this paper deduces the gelation range of Aai–Bbj type polycondensation. The experimental data are essentially in agreement with our theoretical results.
Investigation of radiation grafting of vinyl acetate onto (tetrafluoroethylene–perfluorovinyl ether) copolymer films
Authors: El‐Sawy Naeem M. , Hegazy El‐Sayed A. , Rabie A. M. , Hamed A. , Miligy G. A. 
Published: May 2005

AbstractA study has been made of radiation‐induced grafting of vinyl acetate (VAc) on to (tetrafluoroethylene–perfluorovinyl ether) copolymer (PFA). Effects of grafting conditions such as inhibitor and monomer concentrations and irradiation dose on the grafting yield were investigated. In this grafting system, ammonium ferrous sulphate (Mohr′s salt) was added to the monomer‐solvent mixture to minimize the homopolymerization of VAc and the most suitable concentration was found to be 2.0 wt%. It was found that the dependence of the initial grafting rate on monomer concentration is of the order 1.5. The degree of grafting tends to level off at high irradiation doses due to the recombination of formed free radicals without initiating graft polymerization. Some properties of the prepared graft copolymer such as swelling behaviour, electrical conductivity, thermal and mechanical properties were also investigated. The electrical conductivity was improved by hydrolysis of poly(vinyl acetate) in the grafted chains to their respective vinyl alcohols. The tensile properties were improved by grafting; however, the elongation percent decreased. The DTA data showed thermal stability of such graft copolymers for temperatures up to 300°C, but stability decreased at higher temperatures.
Thermosetting polyethersulphone oligomers
Authors: Parker D. G. , Wheatley G. W. 
Published: May 2005

AbstractRoutes to thermosetting polyethersulphones (PES) by endcapping an hydroxy terminated oligomer with thermally reactive propargyl, vinylbenzyl and cyanate groups were investigated. Model compounds were prepared to establish suitable routes to the reactive oligomers. DSC was used to study curing behaviour of oligomers and model compounds.
Solid state NMR study of the polymerisation of poly(ether sulphone)
Authors: Clayden Nigel J. , Parker David G. , Thorogood Adrian S. , Rose John B. 
Published: May 2005

AbstractThe synthesis of poly(ether sulphone) using the ‘carbonate’ route based on the reaction of 4,4′‐dihydroxydiphenylsulphone, 4,4‐dichlorodiphenylsulphone and potassium carbonate dispersed in diphenylsulphone has been studied by 13C CPMAS NMR spectroscopy. In the initial reaction the half potassium salt of 4,4′‐dihydroxydiphenylsulphone is formed. No evidence for a stable full salt was found at any time during the polymerisation cycle and no appreciable oligomer formation took place before the polymerisation itself took place.
Radiation effects of an electron beam on the microhardness of poly(methyl methacrylate): Poly(chlorotrifluoroethylene) polyblends
Authors: Bajpai R. , Agrawal Pragyesh , Datt S. C. 
Published: May 2005

AbstractSpecimens of poly(methyl methacrylate) (PMMA): poly(chlorotrifluoroethylene) (PCTFE) polyblends with different weight percentage ratios were subjected to electron beam irradiation (1–10 Mrad). The effect of irradiation on the strength of the blend specimens was studied by measuring the surface microhardness using a Vicker's microhardness tester attached to a Carl Zeiss NU 2 Universal research microscope. Significant changes were observed in the Vicker's hardness number, Hv. An irradiation dose of 3 Mrad was found to enhance greatly the microhardness level of the specimens. An increase of approximately 78% in microhardness was observed as the radiation dose was increased from 1 to 3 Mrad. Electron irradiation was also found to induce crosslinking and degradation in the material. The degree of crosslinking was found to be maximum at a dose of 3 Mrad. Specimens incorporating 10 wt% PCTFE were found to exhibit the highest level of microhardness at all radiation doses.
Microencapsulation by coacervation of poly(lactide‐co‐glycolide). III. Characterization of the final microspheres
Authors: Nihant N. , Stassen S. , Grandfils C. , Jérome R. , Teyssié Ph. , Goffinet G. 
Published: May 2005

AbstractThis paper deals with protein microencapsulation by coacervation of poly(lactide‐co‐glycolide) solutions in CH2Cl2 induced by the addition of silicone oils of various viscosities.This coating technique proceeds along three steps: phase separation of the coating polyester, adsorption of the coacervate droplets around the protein phase, and hardening of microparticles. Size distribution, surface morphology and internal porosity of the final microspheres clearly depend on the main characteristics of the coacervate, particularly the viscosity, in a direct connection with the CH2Cl2 content. Indeed, the whole porosity (which may be as high as 80%), average pore size and broadness of pore size distribution decrease as the coacervate is more viscous. Hardening of the coacervate droplets is thus so fast that the organic solvent is entrapped within the polymer matrix and predetermines the internal porosity. Finally, size distribution of microspheres is bimodal in a clear relation with the coacervate viscosity. A less viscous coacervate favours smaller microspheres (within the 7–90 μm range), contaminated with a minor population of microparticles below 4 μm.
Dispersion polymerization of styrene in aqueous alcohol solution: Effects of reaction parameters on the polymer particle formation
Authors: Uyama Hiroshi , Kobayashi Shiro 
Published: May 2005

AbstractDispersion polymerization of styrene in an aqueous alcohol solution using poly(2‐ethyl‐2‐oxazoline) as a polymeric stabilizer was performed to prepare micron‐size monodisperse polystyrene particles. As the water content of the solvent increased, the polymerization rate and the molecular weight of the polymer particles increased and the particle size decreased. Effects of concentrations of stabilizer and initiator upon the polymerization and the size of the resulting polystyrene particles have been examined in the solvent containing different water contents.
Monomer‐Isomerization polymerization. XXVIII. Catalytic activity of transition metals and alkylaluminums in monomer‐isomerization polymerization of 2‐butene
Authors: Endo Kiyoshi , Ueda Ryuichi , Otsu Takayuki 
Published: May 2005

AbstractMonomer‐isomerization polymerization of cis‐2‐butene (c2B) with Ziegler–Natta catalysts was studied to find a highly active catalyst. Among the transition metals [TiCl3, TiCl4, VCl3, VOCl3, and V (acac)3] and alkylauminums used, TiCl3R3Al (R = C2H5 and i‐C4H9) was found to show a high‐activity for monomer‐isomerization polymerization of c2B. The polymer yield was low with TiCl4(C2H5)3Al catalyst. However, when NiCl2 was added to this catalyst, the polymer yield increased. With TiCl3(C2H5)3Al catalyst, the effect of the Al/Ti molar ratio was observed and a maximum for the polymer yields was obtained at molar ratios of 2.0–3.0, but the isomerization increased as a function of Al/Ti molar ratio. The valence state of titanium on active sites for isomerization and polymerization is discussed.
Monomer‐Isomerization polymerization. XXX. Influence of type of TiCl3 on monomer‐isomerization polymerization of 2‐butene with TiCl3 and alkylaluminum catalyst
Authors: Endo Kiyoshi , Ueda Ryuichi , Otsu Takayuki 
Published: May 2005

AbstractMonomer‐isomerization polymerization of cis‐2‐butene with four types of TiCl3 in combination with alkylaluminum compounds was investigated. The catalytic activities for monomer‐isomerization polymerization were found to be influenced by the type of TiCl3 employed: systems containing hydrogen‐activated‐TiCl3 and Solvay‐TiCl3 in combination with R3Al (R = C2H5 and i‐C4H9) showed high catalytic activity for both isomerization and polymerization, whereas (C2H5)2AlCl in combination with any type of TiCl3 did not induce the monomer‐isomerization polymerization. The addition effect of NiCl2 to the TiCl3(C2H5)3Al catalyst was examined. Catalytic activities for both polymerization and isomerization reactions were found to depend on the amount of NiCl2 added.
Copolymerization of new pyrazolone‐containing monomers with certain vinyl comonomers
Authors: Todorova Olga G. , Gitsov Ivan , Borissov Georgi , Terebenina Alevtina 
Published: May 2005

AbstractThe polymerization ability of two new pyrazolone‐containing monomers—3‐methyl‐1‐phenyl‐4‐crotonoyl‐pyrazolone‐5 (Cr) and 3‐methyl‐1‐phenyl‐4‐(3′‐phenyl‐acryloyl) pyrazolone‐5 (Cy)—was investigated. The monomers were obtained by acylation of 3‐methyl‐1‐phenyl‐pyrazolone‐5 with crotonyl chloride or cinnamoyl chloride, respectively. It was established that the two monomers do not homopolymerize either under the action of ionic and radical initiators nor with γ‐rays (doses between 2 and 10 MRad). In contrast to this, the two monomers copolymerize with other vinyl comonomers. Copolymers of Cr and Cy with methacrylic acid (MAA), methyl methacrylate (MMA), and Styrene (St) were synthesized by radical copolymerization. The molecular weights of the polymer products obtained were in the 10,000–65,000 range. It was established that the molecular weight characteristics of the copolymers were affected by the concentration of the pyrazolone‐containing monomer and by the chemical nature of the solvent used. The copolymerization of Cr and Cy with MAA was investigated in detail in order to evaluate the relative activity of the new monomers during copolymerization. The reactivity ratios (r) were calculated by three different methods with good agreement. The values obtained for the monomer pairs are: rMAA = 0.61 ± 0.01, rCr = 0.04 ± 0.01; rMAA = 0.64 ± 0.05, rCy = 0.02 ± 0.02. The Q/e values for Cr and Cy were determined using the reactivity ratios of both monomers.
Vibrational analysis for the all‐trans ferroelectric phase conformation of P (VDF) homopolymer and of P(VDF/TrFE) copolymer: A cluster‐lattice calculation
Authors: Ordejón P. , Martínez E. , Plans J. 
Published: May 2005

AbstractGreen's functions formalism and transfer matrix method have been used to predict the spectra of all‐trans poly(vinylidene fluoride) and the expected changes for poly(vinylidene fluoride/trifluoroethylene) copolymers with the same chain conformation. We find that the use of a simple cluster‐lattice calculation, where the impurity cluster is a trifluoroethylene (TrFE) unit immersed in a poly(vinylidene fluoride) [P(VDF)] regular chain, can explain the main features observed by infrared and Raman spectroscopy in the frequency range 800 to 1450 cm−1. The bands associated to vibration modes of regular VDF sequences, like the 880, 1070, 1280, and 1430 cm−1 ones, are predicted to decrease or even to disappear with increasing TrFE content. The appearance of new peaks at 970, 1300, 1330, and 1410 cm−1 is also discussed.
The bending recovery of polymer films. I. A phenomenological model
Authors: Greener J. , Tsou A. H. , Ng K. C. , Chen W. A. 
Published: May 2005

AbstractWhen a flat film is bent to some fixed curvature, held at this state for some time, and then released, its curvature is usually observed to drop instantaneously to some finite value and then gradually decrease with time. This phenomenon, generally referred to as bending recovery, has been modeled by simple extension of the classical plate‐bending theory to linear‐viscoelastic materials. The model assumes that the relaxation spectra in tension and compression are dissimilar but are interrelated through a simple temporal shift. Experimental data, including instantaneous recovery at ambient and elevated temperatures as well as recovery over extended times, have been generated for four films with widely different relaxation characteristics. The data are in reasonable agreement with predictions of the model if a constant value of the compressive shift parameter (see text) is used for all materials. The model indicates that the bending recovery of a polymer film is intimately related to its relaxation spectrum and can be effectively manipulated by changes in temperature and winding time.
Solid polymers doped with rare earth metal salts. I. Complex formation and morphology in the neodymium chloride–poly(ethylene oxide) system
Authors: Twomey Conor J. , Chen Shaw H. 
Published: May 2005

AbstractThe complex formation and morphology of the NdCl3−PEO system have been investigated. Peak shifts, peak broadening, and the appearance of new peaks in the 800–1200 cm−1 range of the infrared (IR) spectra, by comparison with what is observed with pure PEO, unequivocally demonstrates complex formation. Although the NdCl3−PEO complex is found to be highly hygroscopic, residual moisture can be removed reversibly, thereby permitting the role of water in affecting the morphology of the solid film to be examined. As elucidated with infrared, differential scanning calorimetry, thermogravimetric analysis, and hot‐stage polarized optical microscopy, under anhydrous conditions the resultant complex is amorphous at an EO/NdCl3 ratio approximately less than ca. 8; but above this critical value the PEO in excess of the stoichiometric ratio required for complexation tends to form a separate crystalline phase. Furthermore, water was found to compete with the ethylene oxide unit for complexation with Nd3+, resulting in phase‐separated PEO with a tendency toward crystallinity. The glass transition temperature of the complex is found to increase sigmoidally with the NdCl3 content, an observation further substantiating complexation between NdCl3 and PEO.
Interatomic correlation in partially oriented polymer fibers
Authors: Hristov H. A. , Barton R. , Schultz J. M. 
Published: May 2005

AbstractThe atomic ordering in materials possessing cylindrical symmetry can be investigated by an approximation of the cylindrical distribution function in a given direction. The approximation gives correctly the extent of the interatomic correlation for a wide class of polymer fibers and reduces considerably the amount of the experimental and computational times.
Dispersion of Samples and Sample‐feeding for Counting Methods
Authors: Heidenreich Eberhard , Stintz G. Michael 
Published: May 2005

AbstractThe currently used methods of sample preparation are examined and found to be unsatisfactory in case of counting methods for particle size analysis. It is the purpose of this paper to review the results of investigations of two different measuring principles (light extinction and electrical resistance change) by use of the same signal handling equipment. The commonly used techniques and units are compared with regard to the resulting density distributions of particle size below 0.25 mm. The final conclusions including recommendations to the use of ultrasonic treatment and to improvements of the sampling and the sample‐feeding units are valid for all counting methods.
Online Measurement of the Grain Size Distribution of Sand 0–4 mm used for the production of concrete
Authors: Eder Theodor , Rötzer Harald , Donhoffer Dieter , Leo Riedlmayer , Volkmann Werner , Wallisch Karl , Zöhrer Johann 
Published: May 2005

AbstractAn apparatus is described for the fast and automatic measurement of the grain size distribution of sand ranging from 0 to 4 mm. A sample of sand continuously introduced at a rate of 30 g/min is separated by the apparatus into seven fractions of 0–0.063, 0.063–0.125, 0.125–0.25, 0.25–0.5, 0.5–1, 1–2, and 2–4 mm. The amount of sand in each of these fractions is determined and the results are given in time intervals of 1 minute. The sand is separated in a separation chamber through which water streams in a horizontal laminar flow. The samples are separated according to their settling velocities. The four coarse fractions descend to the bottom of the chamber. They are collected and weighed under water. The three fine fractions remain suspended in three effluent water streams. The quantity of sand is measured in flow cells by absorption of laser light. Control of the system as well as the collection and processing of the measured data are done by means of an electronic control unit and a microcomputer.
Application of an Electrical Conductivity Microprobe for the Characterization of bubble behavior in gas‐liquid bubble flow
Authors: Steinemann Jürgen , Buchholz Rainer 
Published: May 2005

AbstractIn this paper a new electrical conductivity technique for the measurement of bubble size and velocity is presented. This measuring system is able not only to estimate size and velocity of particles (bubbles and droplets in liquids) but also to give complete information on the space related motion of particles. Thus a significant improvement is achieved in the accuracy of measurement.By using the simultanous measurement of both: bubble sizes and volumetric hold up of the dispersed phase, one is able to calculate the local interfacial area. In the first part of this paper the measuring system, its properties and limits are illustrated. In the second part results obtained in a bubble column will be presented.
Drop‐Size Distributions Produced by Pressure Nozzles
Authors: Schegk Claus‐Detlef , Löffler Friedrich 
Published: May 2005

AbstractMeasured drop‐size distributions are presented which were obtained by the atomization of water with hollow‐cone nozzles. The drop‐size distributions were determined using a scatteredlight particle size counting analyser at various locations in the droplet cone. These local distributions change systematically from the cone's axis to its border. To acquire the drop‐size distribution of all the drops the local distributions have to be superimposed. The spatial mass flow distribution in the cone can be calculated from these measurements.