bluuebunny/crossref_metadata_2025_split huggingface dataset:
Altered AMPA receptor expression with treadmill exercise in the 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine‐lesioned mouse model of basal ganglia injury
Authors: VanLeeuwen Jon‐Eric , Petzinger Giselle M. , Walsh John P. , Akopian Garnik K. , Vuckovic Marta , Jakowec Michael W. 
Published: September 2009

AbstractDopamine depletion leads to impaired motor performance and increased glutamatergic‐mediated hyperexcitability of medium spiny neurons in the basal ganglia. Intensive treadmill exercise improves motor performance in both saline treatment and the 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) mouse model of Parkinson's disease. In the present study, we investigated the effect of high‐intensity treadmill exercise on changes in alpha‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptor (AMPAR) subunit expression, because these receptor channels confer the majority of fast excitatory neurotransmission in the brain, and their subunit composition provides a key mechanism for regulating synaptic strength and synaptic neuroplasticity and is important in modulating glutamatergic neurotransmission. Within the dorsolateral striatum of MPTP mice, treadmill exercise increased GluR2 subunit expression, with no significant effect on GluR1. Furthermore, neurophysiological studies demonstrated a reduction in the size of excitatory postsynaptic currents (EPSCs) in striatal medium spiny neurons (as determined by the input‐output relationship), reduced amplitude of spontaneous EPSCs, and a loss of polyamine‐sensitive inward rectification, all supportive of an increase in heteromeric AMPAR channels containing the GluR2 subunit. Phosphorylation of GluR2 at serine 880 in both saline‐treated and MPTP mice suggests that exercise may also influence AMPAR trafficking and thus synaptic strength within the striatum. Finally, treadmill exercise also altered flip isoforms of GluR2 and GluR1 mRNA transcripts. These findings suggest a role for AMPARs in mediating the beneficial effects of exercise and support the idea that adaptive changes in GluR2 subunit expression may be important in modulating experience‐dependent neuroplasticity of the injured basal ganglia. © 2009 Wiley‐Liss, Inc.
Features of sequential learning in hemicerebellectomized rats
Authors: Mandolesi L. , Foti F. , Cutuli D. , Laricchiuta D. , Gelfo F. , De Bartolo P. , Petrosini L. 
Published: September 2009

AbstractBecause the sequencing property is one of the functions in which cerebellar circuits are involved, it is important to analyze the features of sequential learning in the presence of cerebellar damage. Hemicerebellectomized and control rats were tested in a four‐choice visuomotor learning task that required both the detection of a specific sequence of correct choices and the acquisition of procedural rules about how to perform the task. The findings indicate that the presence of the hemicerebellectomy did not affect the first phases of detection and acquisition of the sequential visuomotor task, delayed but did not prevent the learning of the sequential task, slowed down speed‐up and proceduralization phases, and loosened the reward‐response associative structure. The performances of hemicerebellectomized animals in the serial learning task as well as in the open field task demonstrated that the delayed sequential learning task could not be ascribed to impairment of motor functions or discriminative abilities or to low levels of motivation. The delay in sequential learning observed in the presence of a cerebellar lesion appeared to be related mainly to a delay of the automatization of the response. In conclusion, it may be advanced that, through cortical and subcortical connections, the cerebellum provides the acquisition of rapid and accurate sensory‐guided sequence of responses. © 2009 Wiley‐Liss, Inc.
Theory of the evolution of 2D band in the Raman spectra of monolayer and bilayer graphene with laser excitation energy
Authors: Wang Hui , You Jinghan , Wang Lin , Feng Min , Wang Yufang 
Published: September 2009

AbstractA double‐resonance process gives rise to the 2D band in the Raman spectra of monolayer and bilayer graphene. Based on the electronic and vibrational dispersion energies of graphene, the wavenumbers of the 2D band were calculated under different laser excitation energies (from 1.0 to 4.4 eV). Calculated results are in good agreement with experimental data and reproduce the experimental dispersion slope of the 2D band very well. The calculated wavenumbers of the 2D band do not show a linear dependence on the laser excitation energies. Moreover, it is explained that the lowest wavenumber peak of the 2D band of the bilayer graphene, which is composed of four components, has the largest slope with laser excitation energy. Copyright © 2009 John Wiley & Sons, Ltd.
Capillary electrophoretic enantioseparation of m‐nisoldipine using two different β‐cyclodextrins
Authors: Kong Dezhi , Yang Wei , Duan Kunfeng , Cui Yang , Xing Songsong , Zhang Xiaowei , Sheng Xiaona , Zhang Lantong 
Published: September 2009

AbstractThe methods for the enantioseparation of m‐nisoldipine, a new 1,4‐dihydropyridine calcium ion antagonist, were developed. The elaborated methods of m‐nisoldipine enantiomers separation were successfully performed using an anionic CD–sulfobutyl ether‐β‐CD (SBE‐β‐CD) or carboxymethyl‐β‐CD as chiral selector. However, the results indicated that SBE‐β‐CD was a better chiral selector for enantioseparation of the neutral m‐nisoldipine. Furthermore, comparing the two SBE‐β‐CDs, the derivative with a higher degree of substitution (DS) of 7.0 induced better enantioresolution than the one with low DS (4.0). In addition, possible chiral recognition mechanisms of dihydropyridines were discussed.
Preparation of terbutylazine imprinted polymer microspheres using viscous polymerization solvents
Authors: Horváth Viola , Lorántfy Bettina , Tóth Blanka , Bognár Júlia , László Krisztina , Horvai George 
Published: September 2009

AbstractSpherical micron sized terbutylazine imprinted polymers have been obtained by copolymerization of acrylates in solvent mixtures containing a highly viscous (‘oil’) component. The new method requires much less organic solvent than precipitation polymerization to produce spherical MIP particles. Different proportions of oil have been used to clarify its role on the morphology. The particles obtained with the optimal composition could be easily packed into short HPLC columns. Chromatographic retention of the template and other compounds has been determined on the novel (‘OMIP’) columns and was compared to MIP prepared by bulk polymerization. In 70% aqueous acetonitrile eluent the OMIP shows a higher imprinting factor (i. e. less non‐selective binding) and lower retention than the bulk MIP. The chromatographic selectivity against template analogs is similar on OMIP and bulk MIP, while the selectivity against non‐related substances is better on the OMIP. The effect of oil on the polymer structure appears to be due to its high viscosity.
Effects of variation in modulator temperature during cryogenic modulation in comprehensive two‐dimensional gas chromatography
Authors: Begnaud Frédéric , Debonneville Christian , Probst Jean‐Pierre , Chaintreau Alain , Morrison Paul D. , Adcock Jacqui L. , Marriott Philip J. 
Published: September 2009

AbstractMany modulation systems in comprehensive 2D GC (GC×GC) are based on cryogenic methods. High trapping temperatures in these systems can result in ineffective trapping of the more volatile compounds, whilst temperatures that are too low can prevent efficient remobilisation of some compounds. To better understand the trapping and release of compounds over a wide range of volatilities, we have investigated a number of different constant temperature modulator settings, and have also examined a constant temperature differential between the cryo‐trap and the chromatographic oven. These investigations have led us to modify the temperature regulation capabilities of the longitudinally modulated cryogenic system (LMCS). In contrast to the current system, where the user sets a constant temperature for the cooling chamber, the user now sets the temperature difference between the cryo‐trap and the chromatographic oven. In this configuration, the cooling chamber temperature increases during the chromatographic run, tracking the oven temperature ramp. This produces more efficient, volatility‐dependent modulation, and increases the range of volatile compounds that can be analysed under optimal trap‐and‐release conditions within a single analytical run. This system also reduces cryogenic fluid consumption.
Surface Properties of Mesophase‐Forming Fluorinated Bicycloacrylate/Polysiloxane Methacrylate Copolymers
Authors: Martinelli Elisa , Glisenti Antonella , Gallot Bernard , Galli Giancarlo 
Published: September 2009

AbstractNovel random copolymers were synthesized by free‐radical polymerization of a bicycloacrylate monomer carrying a fluorocarbon chain side group (BAF10) with a methacrylate monomer having a polysiloxane side graft (SiMA). The copolymers with higher contents of BAF10 gave rise to a well‐ordered smectic bilayer mesophase. The surface structure of the derived polymer films was investigated by measurements of the contact angle with several interrogating liquids and X‐ray photoelectron spectroscopy (XPS) at different photoemission angles. The values of the contact angles were used to evaluate the film surface tension, following different additive‐component and equation‐of‐state methods. The low surface energies found were attributed to the pronounced hydrophobicity and oleophobicity of the outermost surface caused by the preferential segregation of the fluorocarbon chains to the polymer–air interface.magnified image
Click Chemistry Approach to Rhodamine B‐Capped Polyrotaxanes and their Unique Fluorescence Properties
Authors: Wu Jiayan , Gao Chao 
Published: September 2009

AbstractA fluorescent polyrotaxane (PR) made from the diazido‐poly(ethylene glycol) (N3‐PEG‐N3) axis, α‐cyclodextrins, and alkyne‐functionalized rhodamine B (RhB‐alk) stoppers via Cu(I)‐catalyzed azide–alkyne click chemistry is reported. A nanowire‐like morphology of the prepared fluorescent PRs was visualized by atomic force microscopy. The fluorescence emission intensities of RhB‐capped PEG (RhB‐PEG‐RhB) and the PR were much higher than that of neat RhB or RhB‐alk with the same concentration of RhB fluorophore in both dimethylsulfoxide and alkaline aqueous solutions. Fluorescence lifetimes were detected as 3.59, 3.31, 2.99, and 2.99 ns for neat RhB, RhB‐alk, RhB‐PEG‐RhB, and the PR, respectively. The PRs with unique fluorescence properties might have further applications in the fields of biomedicine and bionanotechnology.magnified image
Magnetic resonance spectroscopy shows an inverse correlation between intramyocellular lipid content in human calf muscle and local glycogen synthesis rate
Authors: van der Graaf Marinette , Tack Cees J. , de Haan Jacco H. , Klomp Dennis W. J. , Heerschap Arend 
Published: September 2009

AbstractIntramyocellular lipid (IMCL) content of skeletal muscle, as measured with 1H MRS, is inversely correlated with insulin sensitivity as determined by whole body glucose uptake. The latter, however, does not necessarily represent the actual glucose uptake in the corresponding skeletal muscle. In this study, we examined whether IMCL content in human calf muscle correlated with local glucose uptake assessed by measurement of glycogen synthesis rate within the same muscle compartment. We studied 20 subjects belonging to four subgroups of five persons each: young lean, elderly lean, young obese and elderly obese. IMCL content in the soleus and gastrocnemius muscle was determined using 1H MR spectroscopic imaging and local glycogen synthesis rate in the calf muscle was measured by 13C MRS during a euglycaemic hyperinsulinaemic clamp with 20% w/v 30% 13C‐1‐labelled glucose infusion. Significantly higher IMCL contents were found in elderly (soleus: p < 0.0001 and gastrocnemius: p < 0.01) and obese subjects (p < 0.01 for both muscles). Local glycogen synthesis rate decreased significantly with obesity (p < 0.01). The principal finding of this study was that the mean IMCL content of the soleus and gastrocnemius muscles was indeed inversely correlated with the local glycogen synthesis rate in the calf muscle (rs = −0.50, p < 0.05), with a very similar dependency as the inverse correlation between mean IMCL content and total body glucose uptake (rs = −0.54, p < 0.05). We conclude that IMCL content of the soleus and gastrocnemius muscles reflects a measure for local insulin resistance within the same muscle compartment as determined by glycogen synthesis rate. Although the inverse correlation suggests that insulin sensitivity is affected by the local amount of fat present, it remains to be determined if this is a cause or a consequence. Copyright © 2009 John Wiley & Sons, Ltd.
Crystallization behavior and thermal property of biodegradable poly(3‐hydroxybutyrate)/multi‐walled carbon nanotubes nanocomposite
Authors: Xu Changling , Qiu Zhaobin 
Published: September 2009

AbstractBiodegradable poly(3‐hydroxybutyrate) (PHB)/functionalized multi‐walled carbon nanotubes (f‐MWNTs) nanocomposite was prepared in this work by solution casting method at 2 wt% f‐MWNTs loading. Scanning electron microscopy and transmission electron microscopy observations indicate a homogeneous distribution of f‐MWNTs in the PHB matrix. Nonisothermal melt crystallization, overall isothermal melt crystallization kinetics, and crystalline morphology of neat PHB and the PHB/f‐MWNTs nanocomposite were studied in detail. It is found that the presence of f‐MWNTs enhances the crystallization of PHB during nonisothermal and isothermal melt crystallization processes in the nanocomposite due to the heterogeneous nucleation effect of f‐MWNTs. Moreover, the incorporation of a small quantity of f‐MWNTs apparently improves the thermal stability of the PHB/f‐MWNTs nanocomposite with respect to neat PHB. Two methods are employed to study the activation energies of thermal degradation for both the neat PHB and the PHB/f‐MWNTs nanocomposite. The activation energy of thermal degradation of the PHB/f‐MWNTs nanocomposite is higher than that of neat PHB. Copyright © 2009 John Wiley & Sons, Ltd.
Deep‐red emissive conjugated poly(2,6‐BODIPY‐ethynylene)s bearing alkyl side chains
Authors: Donuru Venkat R. , Vegesna Giri K. , Velayudham Singaravelu , Meng Ge , Liu Haiying 
Published: September 2009

AbstractNovel deep‐red emissive poly(2,6‐BODIPY‐ethynylene)s bearing dodecyl side chains (polymersA,B, andC) have been prepared by palladium‐catalyzed Sonogashira polymerization of 2,6‐diiodo‐functionalized BODIPY monomers with 2,6‐diethynyl‐functionalized BODIPY monomers. These polymers emit in the deep‐red region with emission maxima at up to 690 nm, and exhibit significant red shifts (up to 166 and 179 nm) of both absorption and emission maxima compared with their parent BODIPY dyes due to significant extension of π‐conjugation. These polymers possess good thermal stability with decomposition temperature between 270 and 360 °C. The polymers exhibit a little larger Stokes shifts and shorter lifetime than their corresponding BODIPY dyes. The solid state thin films of polymersA,B, andCemit in near‐infrared region between 723 and 743 nm, and show significantly red shifts (up to 57 nm) in absorption and emission maxima relative to their polymer solution. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5354–5366, 2009
Development of synthetic double helical polymers and oligomers
Authors: Furusho Yoshio , Yashima Eiji 
Published: September 2009

AbstractThere is growing interest in the design and synthesis of artificial helical polymers and oligomers, in connection with biological importance as well as development of novel chiral materials. Since the discovery of the helical structure of isotactic polypropylene, a significant advancement has been achieved for synthetic polymers and oligomers with a single helical conformation for about half a century. In contrast, the chemistry of double helical counterparts is still premature. This short review highlights the recent advances in the synthesis, structures, and functions of double helical polymers and oligomers, featuring an important role of supramolecular chemistry in the design and synthesis of double helices. Although the artificial double helices reported to date are still limited in number, recent advancement of supramolecular chemistry provides plenty of structural motifs for new designs. Therefore, artificial double helices hold great promise as a new class of compounds. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5195–5207, 2009
Ferroelectric behavior and structural change of poly(trimethylene terephthalate) induced by external electric field
Authors: Matsuda Yasuhiro , Nakano Gaku , Tasaka Shigeru 
Published: September 2009

AbstractThe ferroelectric behavior and structural change induced by the external electric field were observed for poly(trimethylene terephthalate) (PTT), which has nonpolar crystalline structure with carbonyl groups aligned antiparallel to each other. The displacement‐electric field hysteresis curves of PTT films showed hysteresis above 140 °C, which indicated the polarization reversal of PTT. The pyroelectric constant and thermally stimulated depolarization current suggest the depolarization of the polar structure of PTT induced by the external electric field above 150 °C. An endothermic peak caused by the depolarization was also observed in the differential scanning calorimetry for the PTT film poled at 30 MV/m. The change of the crystalline structure and the orientation of carbonyl groups induced by the electric filed were investigated by X‐ray diffraction patterns and infrared spectra. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1991–1996, 2009
Mechanical Spectral Hole Burning in polymer solutions
Authors: Qin Qian , Doen Hiroko , McKenna Gregory B. 
Published: September 2009

AbstractMechanical Spectral Hole Burning (MSHB) was previously developed to investigate dynamic heterogeneity for polymeric materials, which exhibit relatively weak dielectric responses. In our previous work, MSHB was applied to a densely entangled block copolymer and successfully distinguishes the heterogeneous from the homogeneous states. Here, a series of polystyrene (PS) solutions was chosen to further investigate the effect of different types of heterogeneity on mechanical spectral hole burning. The three types of heterogeneity of interest include the entanglement spacing, the entanglement density (or number of entanglements per chain), and chain end density. The heterogeneity was varied by changing either solution concentration or molecular weight of the PS. Different types of dynamics from close to the Rouse regime into the terminal region were also examined. Our results are consistent with a heterogeneous dynamics over the time scales from close to Rouse regime into the rubbery plateau regime and the rubbery plateau‐to‐terminal flow transition regime. Terminal relaxation dynamics, on the other hand, were found to be homogeneous for the PS/diethyl phthalate solutions investigated. The results also indicate the hole properties are dominated by the type of dynamics rather than the length scale of heterogeneity. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2047–2062, 2009
Adhesion of Ti and TiC Coatings on PMMA Subject to Plasma Treatment: Effect of Intermediate Layers of Al2O3 and TiO2 Deposited by Atomic Layer Deposition
Authors: Kääriäinen Tommi O. , Cameron David C. , Tanttari Mari 
Published: September 2009

AbstractMagnetron sputtered metal and metal compound films generally show very poor adhesion to PMMA; this limits the use of the polymer for components which are wear or scratch resistant or have a decorative finish. We have shown that adhesion could be significantly improved by a duplex process where a nanometer‐scale thickness adhesion layer of TiO2 or Al2O3 was deposited by low temperature atomic layer deposition (ALD) prior to magnetron sputtering. The metal precursors used for TiO2 and Al2O3 were TDMAT and TMA, respectively, and ozone was used as a source of oxygen in both processes. This process was followed by deposition of the metal/metal carbide layer using pulsed DC reactive magnetron sputtering. With the presence of the ALD adhesion layer, the pull‐off adhesion strength increased with its thickness until a point where the failure mechanism was due to cohesive disruption of the substrate material itself. It has been shown that the ALD deposited layers protect the PMMA against plasma damage during the sputtering process by blocking both direct ion damage and disruption of the polymer structure by ultra‐violet radiation.magnified image
Study on the Thermal Stability of Ti(C,O,N) Decorative Coatings
Authors: Moura Cacilda , Cunha Luís , Chappé Jean Marie , Vaz Filipe 
Published: September 2009

AbstractThis work reports on the study of thermal stability of dark decorative Ti(C,O,N) thin films produced by reactive magnetron sputtering, from a pure titanium target, using acetylene and an oxygen and nitrogen mixture as reactive gases. The thermal resistance and evolution of structural and physical properties were studied by performing annealing experiments at three different temperatures: 800, 900 and 1 000 °C. In order to study the effect of the thermal treatments on the properties of the films, mainly the physical ones (where surface colourations will deserve particular importance), X‐ray diffraction (XRD) and Raman spectroscopy (RS) were used. The optical properties of the films were obtained by reflectance experiments, in visible region, and the colour of the films is expressed in the CIE 1976 L*a*b* colour space.
Influence of Al Content on the Properties of MgO Grown by Reactive Magnetron Sputtering
Authors: Saraiva Marta , Chen Hong , Leroy Wouter P. , Mahieu Stijn , Jehanathan Neerushana , Lebedev Oleg , Georgieva Violeta , Persoons Rosita , Depla Diederik 
Published: September 2009

AbstractIn the present work, reactive magnetron sputtering in DC mode was used to grow complex oxide thin films, starting from two separate pure metal targets. A series of coatings was produced with a stoichiometry of the film ranging from MgO, over MgxAlyOz to Al2O3. The surface energy, crystallinity, hardness, refractive index, and surface roughness were investigated. A relationship between all properties studied and the Mg content of the samples was found. A critical compositional region for the Mg–Al–O system where all properties exhibit a change was noticed.