bluuebunny/crossref_metadata_2025_split huggingface dataset:
Activity and plasticity in the CA1, the dentate gyrus, and the amygdala following controllable vs. uncontrollable water stress
Authors: Kavushansky Alexandra , Vouimba Rose‐Marie , Cohen Hagit , Richter‐Levin Gal 
Published: September 2005

AbstractThe level of controllability has been shown to modulate the effects of stress on physiology and behavior. In the present study, we investigated the effects of controllable vs. uncontrollable stressors on plasticity in hippocampal CA1, the dentate gyrus (DG), and basal amygdala nucleus (B) in the rat, using the electrophysiological procedure of long‐term potentiation (LTP). A naive group was left undisturbed until the electrophysiological recording commenced. Rats of the two controllable stress groups were trained in the Morris water maze to locate an invisible underwater platform (the first group), or visible platform (the second group), thus escaping from the water, before the recording. The uncontrollable stress group underwent the same procedure (exposure time to water was adjusted to the averaged exposure time of the first controllable group) without the escape platform. We first assessed the effects of stress and controllability on LTP in CA1. Both controllable stressors and the uncontrollable stress impaired CA1 LTP, with a more robust effect induced by the uncontrollable stress. We further assessed the effects of the same procedures on LTP in DG and B. The uncontrollable stress enhanced LTP in DG and increased baseline responses (suggesting uncontrollable stress‐induced plasticity) in the amygdala. All the stressors decreased amygdalar LTP. An assessment of plasma levels of corticosterone (CORT), following the behavioral procedures, revealed an enhancement in CORT release following the uncontrollable, but not controllable stress, indicating the uncontrollable condition as the most stressful. These findings provide insight into the differential effects of stress and stress controllability on different hippocampal subregions and the amygdala. © 2005 Wiley‐Liss, Inc.
Characterizing behavioral and cognitive dysexecutive changes in progressive supranuclear palsy
Authors: Millar David , Griffiths Philipa , Zermansky Adam J. , Burn David J. 
Published: September 2005

AbstractFrontal lobe dysfunction is a prominent feature of many neurological disorders. Early diagnosis may be enhanced by establishing a profile of cognitive, behavioral, and emotional change. Traditional psychometric assessment focuses on cognitive dysfunction and fails to identify behavioral changes, particularly those associated with orbitofrontal dysfunction. We examined progressive supranuclear palsy (PSP), a prototypical subcortical dementia with frontal features, using commonly available neuropsychological measures and a modification of the Katz Adjustment Scale‐Relatives (KAS‐R), an instrument first developed to assess dysexecutive changes in head‐injured patients. Executive tests identified deficits in reasoning, planning, set shifting, verbal fluency, information processing speed, and response initiation. On the KAS‐R, changes in apathy, social withdrawal, and independence were observed, with little change in belligerence, social irresponsibility, uncooperativeness, obstreperousness, anxiety, and depression. The results show the potential utility of this instrument in characterizing behavioral and emotional changes associated with frontal lobe dysfunction in neurodegenerative disease. © 2005 Movement Disorder Society
Magnetization transfer effect on human brain metabolites and macromolecules
Authors: McLean Mary A. , Simister Robert J. , Barker Gareth J. , Duncan John S. 
Published: September 2005

AbstractA pulse sequence was implemented to observe the magnetization transfer (MT) effect on metabolites, water, and macromolecules in human frontal lobes in vivo at 1.5 Tesla. Signals were compared following the application of three hard pulses of 0.745 μT amplitude, applied at frequency offsets of either 2500 Hz or 30 kHz, preceding a conventional point‐resolved spectroscopy (PRESS)‐localized acquisition with an echo time (TE) of 30 ms and repetition time (TR) of 3 s. This gave an MT effect on water in vivo of 46%, while direct saturation by the MT pulses at 2.5 kHz offset was confirmed to be under 4% for all metabolites. We observed significant MT saturation in vivo for N‐acetylated compounds, choline (Cho), myo‐inositol, and lactate (Lac); a trend of an effect on glutamate + glutamine (Glx); and the typically observed effect on creatine (Cr). No significant MT effect was seen on the macromolecule signal, which was observed using metabolite nulling. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Error optimization of a three‐dimensional magnetic resonance imaging tagging‐based cartilage deformation technique
Authors: Neu C. P. , Hull M. L. , Walton J. H. 
Published: September 2005

AbstractThree‐dimensional strain fields in articular cartilage subjected to compressive loading can be determined using a recently developed MRI‐based cartilage deformation by tag registration technique. The objective of this study was to determine the experimental variables that minimize the technique error, which has not been previously reported. Error (strain bias and precision) was determined using direct experiments and Monte Carlo simulations for four variables: spatial resolution, tag line spacing, applied nominal strain, and number of control points used to describe tag lines in a B‐spline model. The important results include the following: (1) bias was not significantly different from zero, (2) precision increased with image resolution and with tag line spacing, (3) precision was independent of applied nominal strain, and (4) error was a minimum (absolute precision = 0.41% strain) for the following values: spatial resolution = 0.05 × 0.05 mm2; tag line spacing = 2.0 mm; control points = 6. With these results the technique can now be used in various applications while minimizing error. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Synthesis of a new type of core–shell particle from hyperbranched polyglycerol
Authors: Wan Decheng , Li Zhongyu , Huang Junlian 
Published: September 2005

AbstractBased on hyperbranched polyglycerol (PG), a route to prepare particles with a novel topology was developed. The hydroxyls of PG were converted to trithiocarbonates, and the latter were used to mediate the surface graft polymerization of N,N‐dimethylaminoethyl acrylate. The poly(N,N‐dimethylaminoethyl acrylate) shell was crosslinked by 1,6‐dibromohexane and then parted from the core by the cleavage of trithiocarbonates with sodium borohydride. Novel particles with thiol groups located on the interface between the PG core and poly(N,N‐dimethylaminoethyl acrylate) shell were thus formed. The shell crosslinking could be performed at very high solid contents (2–4%). These polymer particles showed pH‐ and temperature‐dependent solubility. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5458–5464, 2005
Dual bimodal polyethylene prepared by intercalated silicate with nickel diimine complex
Authors: Wang Qi , Liu Peng 
Published: September 2005

AbstractThe ethylene polymerization was catalyzed by the intercalated montmorillonite with the nickel complex, [ArNC(Me)C(Me)NAr]NiBr2 (Ar = 2,6‐C6H3 (i‐Pr)2). Polymer with low melting point and high molecular weight was produced at the early stage of polymerization followed by formation of polymer with high melting point and low molecular weight. It is proposed that the gallery of silicate lowers the propagation rate of polymerization and frequency of “chain walking” process of nickel complex anchored inside the gallery, which produces polymer with low molecular weight and low branching, whereas the nickel complex immobilized on the surface of silicate generates polymer with high molecular weight and high branching. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5506–5511, 2005
Synthesis of a novel high sensitive photo‐radical initiator with good thermal stability based on naphthalic‐1,8‐N‐alkylimide derivatives
Authors: Sakayori Katsuya , Shibasaki Yuji , Ueda Mitsuru 
Published: September 2005

AbstractA new high‐sensitive photo‐radical initiator, N‐[2‐(2‐acryloyloxyethoxy)ethyl]‐1,8‐naphthalimide (NI6), with good thermal stability based on naphthylimide derivative was developed. NI6 was prepared by the condensation of N‐[2‐(2‐hydroxyethoxy)ethyl]‐1,8‐naphthalimide and acryloyl chloride in the presence of 4‐dimethylaminopyridine. The film consisting of NI6 and pentaerythritol triacrylate (PETA) showed higher photosensitivity than those containing conventional photo‐radical initiators such as acrylic acid 2‐(2‐{2‐[2‐(4‐benzoyl‐phenoxy)‐ethoxy]‐ethoxy}‐ethoxy)‐ethyl ester, cyclohexylmaleimide, and the resulting film exhibited very high transmittance over 400 nm. The thermal stability of NI6 was very high and no decomposed residues were observed from the film consisting of NI6 after heating at 250 °C for 1 h. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5571–5580, 2005
Ethylene/silane copolymers prepared with a metallocene catalyst as polymeric additives in polyethylene/aluminum trihydroxide composites
Authors: Lipponen S. , Seppälä J. 
Published: September 2005

AbstractMetallocene catalyst based polyethylene‐co‐7‐octenyldimethylphenylsilane (PE/SiPh) and its post‐treated functional forms PE/SiX (X = Cl, F, OCH3, OCH2CH3) were used as additives in PE/ATH composites. The impact strength of the composites was significantly increased after a small addition (0.5–3.0 wt %) of the functionalized form of the copolymer (PE/SiX). The thermal study of the composites gave us more information about the additive's behavior at the filler/matrix interphase and correlation to the mechanical properties was found. According to this thermal data, the original untreated form of PE/SiPh also seemed to interact weakly with the ATH‐filler particles, which was seen in an altered interphase at the filler/matrix boundary layer. The interaction was not strong enough to improve the impact strength of composites but an increase was observed in some other mechanical properties (tensile stress, yield strain). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5597–5608, 2005
Effect of the initial maleic anhydride content on the grafting of maleic anhydride onto isotactic polypropylene
Authors: Zhang Ronghua , Zhu Yutian , Zhang Jianguo , Jiang Wei , Yin Jinghua 
Published: September 2005

AbstractA series of 13C‐enriched maleic anhydride grafted isotactic polypropylene samples were prepared in solution at 170 °C by changes in the initial maleic anhydride content. The NMR spectra of the samples showed that the signals of the maleic anhydride attached to the tertiary carbons of the isotactic polypropylene chains increased considerably with increasing maleic anhydride content, whereas the signals of the maleic anhydride on the radical chain ends (with a single bond) arising from β scission did not. On the other hand, the signals of the maleic anhydride on the radical chain ends with double bonds increased markedly with increasing maleic anhydride content, and this suggested that β scission could occur extensively after maleic anhydride was attached to the tertiary carbons. As a result, the molecular weight of the grafted polypropylene decreased significantly with increasing maleic anhydride content in this study. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5529–5534, 2005
Using hydrophobic additive as pore‐forming agent to prepare macroporous PNIPAAm hydrogels
Authors: Zhang Xian‐zheng , Chu Chih‐chang , Zhuo Ren‐xi 
Published: September 2005

AbstractHydrophobic poly(lactic acid) nanospheres were fabricated and used as an additive during the polymerization and gelation process of temperature‐sensitive poly(N‐isopropylacrylamide) (PNIPAAm) hydrogels. The influence of hydrophobic additive on properties of PNIPAAm hydrogels was examined. The interior morphology studied by scanning electron microscopy revealed that the hydrophobic additive induced a macroporous structure in the resulting PNIPAAm hydrogels. Results demonstrate that the hydrophobic additive acts as a pore‐forming agent like conventionally used hydrophilic additive does during the gelation process. Because of the macroporous network and incorporated additives, the temperature‐sensitive characteristics, particularly the equilibrium swelling ratio at room temperature and shrinking rate upon temperature increase of modified PNIPAAm hydrogels, are significantly improved. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5490–5497, 2005
Catalytic effect of ionic liquids in the Cu2O/2,2′‐bipyridine catalyzed living radical polymerization of methyl methacrylate initiated with arenesulfonyl chlorides
Authors: Percec Virgil , Grigoras Cristian 
Published: September 2005

AbstractThe effect of 1‐butyl‐3‐methylimidazolium hexafluorophosphate ionic liquid on the living radical polymerization of methyl methacrylate initiated with arenesulfonyl chlorides and catalyzed by the self‐regulated Cu2O/2,2′‐bipyridine catalyst was investigated. A dramatic acceleration of the living radical polymerization of methyl methacrylate in this ionic liquid was discovered. This accelerated living radical polymerization maintained an initiation efficiency of 100%, eliminated the induction period of this catalyst, and produced poly(methyl methacrylate) with molecular weight distribution of 1.1 and perfect bifunctional chain‐ends. The kinetic analysis of the living radical polymerization in the presence of ionic liquid demonstrated a rate constant of propagation that follows an almost first order of reaction on the ionic liquid concentration and therefore, the ionic liquid exhibits catalytic effect. The catalytic effect of the ionic liquid facilitated the reduction of the catalyst concentration from stoichiometric to catalytic and allowed the decrease of the polymerization temperature from 80 to 22 °C. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5609–5619, 2005
X‐ray study of Bi, Sb and Bi1–x–Sbx alloys
Authors: Shankar Narayana M. , Gopi Krishna N. 
Published: September 2005

AbstractThe mean square amplitudes of vibration, Debye–Waller factors and Debye temperatures of bismuth (Bi), antimony (Sb) and Bi1–x –Sbx alloys have been obtained from X‐ray intensities. The intensities have been measured with Philips 3020 diffractometer fitted with a proportional counter using filtered CuKα radiation at room temperature and have been corrected for thermal diffuse scattering. The X‐ray Debye temperatures obtained for Bi and Sb have been compared with corresponding values obtained from specific heats and elastic constants. The values of Debye temperature obtained for Bi1–x –Sbx alloys have been compared with the values calculated from Kopp–Neumann relation. Vacancy formation energies of Bi, Sb and Bi1–x –Sbx alloys have been estimated using a relation connecting it with the X‐ray Debye temperature. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Small‐signal characteristics of organic semiconductors with continuous energy distribution of traps
Authors: Schmeits M. , Nguyen N. D. 
Published: September 2005

AbstractThe electrical characteristics of organic light emitting devices containing a continuous distribution of trap states in the forbidden gap are obtained by numerically solving the basic semiconductor equations for the steady state and under small‐signal conditions. The spatially‐dependent occupied trap states, which are described by an explicit density of states function, modify the charge distribution within the structure and the shape of the electric field and the carrier current densities. The effect of the modulation frequency, the applied voltage and the device temperature are studied for a hole conducting layer with a trap density of states consisting of a double gaussian profile and for a given set of microscopic parameters including the carrier mobilities and thermal velocities, the capture cross sections, and the residual shallow impurity concentration. The frequency‐dependent loss and capacitance curves are obtained for various experimental conditions, like temperature and applied steady‐state voltage. Effects of parameters describing electrical contacts and trap density of states are shown. Such results are particularly useful for the analysis of experimental electrical characteristics obtained by thermal admittance spectroscopy. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Barrier and mechanical properties of methylcellulose–whey protein films
Authors: Erdohan Z. Özge , Turhan K. Nazan 
Published: September 2005

AbstractWater vapour permeability (WVP) and mechanical properties were assessed in edible films prepared from methylcellulose (MC) and MC–whey protein isolate (WPI) or MC–whey protein concentrate (WPC). Glycerol (Gly) was used as the plasticizer. Two MC–WP films were formulated. For Group I films, the mass ratio of WP : Gly was constant, whereas for Group II films the mass ratio of polymer (MC + WP) : Gly was constant. The WVP of MC–Gly film decreased with increasing MC concentration, while the tensile strength (TS) and percent elongation (E) increased. The WVP of Group I and Group II films decreased erratically and TS increased when the MC concentration was increased. Group I films had higher TS values than Group II films at the same MC : WP ratios. E of both groups increased with increasing MC concentration (p < 0.05), excluding the films with the highest MC : WP ratio tested (0.8) in Group I films. Group I films had lower E values than Group II films at the same MC : WP ratios. MC effectively governed WVP, TS and E of the WP films. Generally, MC–WP films of this work showed lower WVP than that of MC‐ and WP‐based edible films in the literature. This can potentially make MC–WP films a suitable film material for moisture‐sensitive food products. Copyright © 2005 John Wiley & Sons, Ltd.
A new recycling method for expanded polystyrene
Authors: Shin C. 
Published: September 2005

AbstractA new recycling method was investigated in this work, in which polystyrene (PS) sub‐µm fibres were electrospun from recycled expanded polystyrene (EPS). The experimental results in this work show that fibres with diameters of around 500 nm were produced by the electrospinning method. The fibres were produced to form a non‐woven mat. Non‐woven mats of electrospun fibres have large surface areas and small pore sizes compared to commercial textiles, making them excellent materials for use in filtration applications. Copyright © 2005 John Wiley & Sons, Ltd.
A QSAR Study of the Brain/Blood Partition Coefficients on the Basis of pKa Values
Authors: Zhang Huabei 
Published: September 2005

AbstractA database including histamine receptor antagonists and agonists and neutral compounds, physicochemical properties and the equilibrium brain/blood concentration ratios (logBB) were analysed by using linear regression. The correlation between logBB and physicochemical properties has been remarkably improved by grouping the compounds according to their pKa values. For compounds with pKa≥8.5 logBB increases with the maximum atomic positive charge, polarity characterized by the sum of substructural partial charges and decreases with the maximum H‐bond acceptor and the H‐bond donor (n=16, r2=0.864, s=0.316, Q2=0.783). For compounds with a pKa in the range of 6.8≤pKa<8.5 logBB increases with molecular size/bulk (polarizability α) and decreases with polarity and the H‐bond acceptor (n=11, r2=0.892, s=0.246, Q=0.652). For compounds with pKa<6.8 and neutral compounds logBB increases with polarizability and and decreases with the H‐bond acceptor (n=28, r2=0.869, s=0.162, Q2=0.820). logBB of the compounds with high pKa can be also described by logP defined as the difference between logP values measured in 1‐octanol water and those measured in alkane water well, whilst logBB of the neutral compounds and the compounds with low pKa values can be also described by logP(1‐octanol/water) very well, and it seems to be neither logP nor logP can describe logBB of the compounds with intermediate pKa values. These show that the compounds in three groups have different interaction mechanism in brain.
Theoretical study of molecular conduction: I. Effective Green's function based on perturbation theory
Authors: Shimazaki Tomomi , Yamashita Koichi 
Published: September 2005

AbstractThere have been many experimental and theoretical studies on molecular conduction, as it is a fundamental parameter in the study of molecular‐scale electronics. We have investigated the features of molecular conduction using a Green's function method, which has often been used to solve problems in quantum transport and is also effective in elucidating electron transport in molecules. We have obtained the novel effective Green's functions, including the first‐order energy corrections, by accommodating the self‐energy of the electrodes as perturbation terms. Although these approximate Green's functions only provide information on the first‐order energy corrections, they can involve the elementary properties of molecular conduction. We propose a scheme for the analysis of the relations between molecular orbitals and their roles in molecular conduction and present analytical calculations for normal and cyclic polyenes. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Theoretical studies of structural and electronic properties of AlnAsn clusters
Authors: Goswami Biplab , Ghosh Chanchal , Pal Sougata , Sarkar Pranab 
Published: September 2005

AbstractWe present theoretical results of size dependent structural, electronic, and optical properties of ligand‐free stoichiometric AlnAsn clusters of zinc‐blende modification. The investigation is done using a simplified parametrized linear combination of atomic orbital–density functional theory‐local density approximation–tight‐binding (LCAO–DFT–LDA–TB) method and consider clusters with n up to around 100. Initial structures have assumed as spherical parts of infinite zinc‐blende structure and then allowed to relax to the closest local‐energy‐minimum structure. We analyze the radial distributions of atoms, Mulliken populations, electronic energy levels (in particular, HOMO and LUMO), bandgap, and stability as a function of size and composition. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Semiparametric inferences for association with semi‐competing risks data
Authors: Ghosh Debashis 
Published: September 2005

AbstractIn many biomedical studies, it is of interest to assess dependence between bivariate failure time data. We focus here on a special type of such data, referred to as semi‐competing risks data. In this article, we develop methods for making inferences regarding dependence of semi‐competing risks data across strata of a discrete covariateZ. A class of rank statistics for testing constancy of association across strata are proposed; its asymptotic properties are also derived. We develop a novel resampling‐based technique for calculating the variances of the proposed test statistics. In addition, we develop methods for combining test statistics for assessing marginal effects ofZon the dependent censoring variable as well as its effects on association. The finite‐sample properties of the proposed methodology are assessed using simulation studies, and they are applied to data from a leukaemia transplantation study. Copyright © 2005 John Wiley & Sons, Ltd.