bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrochemical Synthesis of Polypyrrole in a Room Temperature Ionic Liquid and Its Properties
Authors: ZHANG Aijian , LIU Yingzi , WANG Huan , ZHANG Guirong , ZHANG Kai , LU Jiaxing 
Published: March 2009

AbstractPolypyrrole (PPy) films were electropolymerized on Pt and indium‐tin‐oxide (ITO) electrodes in a room temperature ionic liquid, 1‐buthyl‐3‐methylimidazolium hexafluorophosphate (bmimPF6). The ionic liquid was used as both the growth medium and the supporting electrolyte. The cyclic voltammetry (CV) shows that the growth of polymer, prepared in ionic liquid was not similar to that prepared in traditional organic media. The polymer was further characterized via AC impedance, in situ UV‐Visible spectroscopy, scanning electron microscopy (SEM), Raman and Fourier transform infrared spectroscopy (FTIR). Both Raman and FTIR spectroscopy results show the characteristic peak of PPy. SEM shows the morphology differences between the both sides of the polymer. The electrocatalytic effect of the PPy modified electrode was investigated in hydroquinone solution and the result exhibited electrocatalytic properties for hydroquinone by the PPy modified electrode.
Two Novel 3D Hydrogen‐bonded Architectures Constructed from Maleic Acid and N‐donor Ligands: Structures, Magnetic Properties and Theoretical Studies
Authors: TANG Long , FU Feng , WANG Wenliang , LI Dongsheng , WU Yapan , GAO Xiaoming , YANG Xiaogang 
Published: March 2009

AbstractBy changing auxiliary ligands, two new Cu(II) complexes, [Cu(mal)(tap)(H2O)]n (1) and [Cu2(mal)2(bpym)2(H2O)2]·2H2O (2) (mal=maleate, tap=1,4,5,8‐tetraazaphenanthrene, bpym=2,2′‐bipyrimidine), have been synthesized and structurally characterized by X‐ray single‐crystal diffraction. Complex 1 shows a 1D arch‐shaped coordination polymer chain, further, the dimensionality is extended to a 3D supramolecular architecture through hydrogen‐bonding and aromatic π‐π stacking interactions. Complex 2 features a 2‐fold interpenetrated 3D→3D supramolecular architecture with 6‐connected α‐Po (46) topology. According to the crystal structures, the full geometry optimizations of complexes 1 and 2 were carried out by using hybrid DFT methods at B3LYP/6‐31G(d) level. Meantime, the DFT‐BS approach was applied to study the magnetic coupling behavior for the two complexes, and the result reveals that the calculated exchange coupling constants J were in good agreement with the experimental data. Both 1 and 2 showed almost the same antiferromagnetic behavior.
A High Performance Theory for Thermodynamic Study on the Binding of Human Serum Albumin with Erbium Chloride
Authors: BEHBEHANI G. Rezaei , DIVSALAR A. , SABOURY A. A. , FARIDBOD F. , GANJALI M. R. 
Published: March 2009

AbstractA thermodynamic study of the interaction between erbium(III) chloride (Er3+) and human serum albumin (HSA) was studied at pH=7.0, 27 and 37 °C in phosphate buffer by isothermal titration calorimetry (ITC). The present study reports the thermodynamic parameters that govern HSA‐Er3+ interactions. The extended solvation theory was used to reproduce the enthalpies of HSA‐Er3+ interactions over the whole range of Er3+ concentrations. The binding parameters recovered from the new model were attributed to the structural change of HSA and its biological activity. The results obtained indicate that there is a set of two identical binding sites for Er3+ ions with negative cooperativity. The enhancement of complex formation by Er3+ and concomitant increase in ?S suggest that the metal ion plays a role in increasing the number of hydrophobic contacts. The binding parameters discovered from the extended solvation model indicate that the stability of HSA molecule is increased as a result of its interaction with Er3+ ions.
Synthesis of Cd(OH)2 with Doughnut Microstructure and Its Controlled Growth Mechanism
Authors: PENG Yin , LIU Zhengyin , YE Feng , WEI Xianwen 
Published: March 2009

AbstractDoughnut‐like Cd(OH)2 microstructure was obtained by a facile solution‐based method using polymer polyacrylamide (PAM) as a crystal growth modifier. Hexagonal flake‐like Cd(OH)2 is the building‐block to assemble doughnut‐like microstructures. The block concaves from one side when PAM is present in the synthesis system. However, nano‐size Cd(OH)2 doughnuts with a hole in the middle part were formed if carboxyl‐functionalized polyacrylamide (PAM‐COOH) was used as a crystal growth modifier. A possible mechanism for the Cd(OH)2 microstructure formation based on typical oriented attachment process in the presence of polymer was discussed. Polymer‐directed crystal growth and mediated self‐assembly of nanocrystals may promise synthesis routes for variously ordered inorganic and inorganic‐organic hybrid materials with complex forms and special structures.
Studies on Triterpenoids and Flavones in Glycyrrhiza uralensis Fisch. by HPLC‐ESI‐MSn and FT‐ICR‐MSn
Authors: MENG Xiangyu , LI Huilin , SONG Fengrui , LIU Chunming , LIU Zhiqiang , LIU Shuying 
Published: March 2009

AbstractSeven compounds, four flavones and three triterpenoids from Glycyrrhiza uralensis Fisch. extract are identified by high performance liquid chromatography coupled with electrospray ionization multi‐tandem mass spectrometry (HPLC‐ESI‐MSn). The fragmentation pathways of these compounds are investigated by ESI‐MSn and Fourier transform ion cyclotron resonance multiple‐stage tandem mass spectrometry (FT‐ICR‐MSn). Comparing the retention times (tR) and mass spectra with those of reference compounds, seven components are identified in Glycyrrhiza uralensis Fisch. and their MSn data proposed plausible schemes for their fragmentation. All the experimental results show that ESI‐MSn and FT‐ICR‐MSn are powerful tools for the structural characterization of triterpenoids and flavones.
Interaction between Xanthoxylin and Bovine Serum Albumin
Authors: WEN Maogui , TIAN Jianniao , HUANG Yonglin , BIAN Hedong , CHEN Zhengfeng , LIANG Hong 
Published: March 2009

AbstractThe interaction between xanthoxylin (XT) and bovine serum albumin (BSA) under simulative physiological conditions has been analyzed in detail by various spectroscopic techniques including fluorescence, circular dichroism (CD), and Fourier transform infrared (FT‐IR) spectroscopy. Fluorescence quenching data revealed that the quenching constants (K) were 3.31×105, 2.03×105 and 0.94×105 L·mol−1 at 286, 298 and 310 K, respectively. Based on the fluorescence results, the fluorescence quenching mechanism of the interaction between XT and BSA has been found to be combined static and dynamic quenching. Thermodynamic parameters ΔH0, ΔS0 and ΔG0 suggested that the hydrophobic force played a main role in binding of XT to BSA. The effect of XT on the conformation of BSA was analyzed by FT‐IR spectroscopy and quantitatively calculated from CD spectroscopy with reduction of α‐helical content by about 3.9%. In addition, the effect of common ions on the binding constant was also discussed.
A Highly Efficient and Environmentally Friendly CMC‐Supported Lanthanide Catalyst for One‐pot Synthesis of Substituted Imidazoles
Authors: WANG Limin , YAO Yinfang , WANG Yonghong , ZOU Gang 
Published: March 2009

AbstractA CMC‐supported lanthanide catalyst was prepared from CMC and isopropoxy lanthanide. This solid Lewis acid catalyst was used in synthesis of substituted imidazoles under mild conditions, showing catalytic activity comparable to the expensive lanthanide Lewis acid Ln(OTf)3. Furthermore, the catalyst could be readily recycled and reused for five times without any appreciable loss in catalytic activity.
Polystyrene‐supported Palladium(II) Ethylenediamine Complex: A Recyclable Catalyst for the Syntheses of 2‐Benzyl‐imidazo[2,1‐b][1,3]benzothiazoles by Sonogashira Reaction
Authors: BAKHERAD Mohammad , BAHRAMIAN Bahram , NASR‐ISFAHANI Hossein , KEIVANLOO Ali , SANG Golnaz 
Published: March 2009

AbstractThe polymer‐supported palladium(II) ethylenediamine complex was used as a catalyst for the heterocyclization during Sonogashira reaction between a substituted phenyl iodide and 2‐amino‐3‐(2‐propynyl)‐1,3‐benzothiazolium bromide, which could readily be recovered from the reaction medium by a simple filtration, and reused without a significant loss in its activity.
Two Metabolites with DNA‐Binding Affinity from the Mangrove Fungus Xylariasp. (#2508) from the South China Sea Coast
Authors: XU Fang , PANG Jiyan , LU Bingtai , WANG Jiajun , ZHANG Yi , SHE Zhigang , VRIJMOED L. L. P. , GARETH JONES E. B. , LIN Yongcheng 
Published: March 2009

AbstractA novel metabolite xylopyridine A (1), together with a known compound pyrocoll (2), was isolated from mangrove endophytic fungus Xylaria sp. (#2508) collected from the South China Sea coast. Their structures were established on the basis of spectroscopic analysis, especially 2D‐NMR. Their affinities toward calf thymus (CT) DNA were studied by fluorescence quenching and spectrophotometric titration experiments. The results indicate that 1 showes strong DNA‐binding affinity presumably via an intercalation mechanism, thus it is exploitable as strong DNA‐binders.
Tin(II) Chloride Dihydrate Catalyzed Groebke Condensation: An Efficient Protocol for the Synthesis of 3‐Aminoimidazo[1,2‐a]pyridines
Authors: SHAABANI Ahmad , SOLEIMANI Ebrahim , SARVARY Afshin , REZAYAN Ali Hossein , MALEKI Ali 
Published: March 2009

AbstractThe ability of tin(II) chloride dihydrate as a catalyst to promote the three‐component condensation reaction from a diversity of aromatic aldehydes, 2‐aminopyridines and isonitriles at room temperature is described. This methodology affords a number of 3‐aminoimidazo[1,2‐a]pyridines in the presence of tin(II) chloride dihydrate as a new and mild Lewis acid catalyst in the multi‐component reaction in reasonable yields and short reaction time without any significant optimization of the reaction conditions.
Hydrolysis of p‐Nitrophenyl Picolinate Catalyzed by Mono‐Schiff Base Complexes with Aza‐crown Ether or Morpholino Pendants
Authors: LI Jianzhang , JIANG Weidong , FENG Famei , XU Bin , HU Wei , ZHANG Jin , QIN Shengying 
Published: March 2009

Abstract Mono‐Schiff base cobalt(II) and manganese(III) complexes with either benzo‐10‐aza‐crown ether pendants (CoL21, MnL21Cl) or morpholino pendants (CoL22, MnL22Cl) have been employed as models for hydrolase enzymes by studying the kinetics of their hydrolysis reactions with p‐nitrophenyl picolinate (PNPP). The kinetic mathematical model of PNPP cleavage catalyzed by these complexes was proposed. The effects of complex structures and reaction temperature on the rate of catalytic PNPP hydrolysis have been also examined. The results showed that the rate increases with pH of the buffer solution and four complexes exhibited high activity in the catalytic PNPP hydrolysis. Compared with the crown‐free analogy CoL22 and MnL22Cl, the crowned Schiff base complexes (CoL21, MnL21Cl) exhibit higher catalytic activity. The pseudo‐first‐order‐rate (kobs) for the PNPP hydrolysis catalyzed by the complex MnL21Cl containing benzo‐10‐aza‐crown ether is 923‐fold higher than that of spontaneous hydrolysis of PNPP at pH=7.00, 25 °C, [S] =2.0×10−4 mol·dm−3.
Palladium‐catalyzed Substitution of Ketone or Aldehyde Bearing Aryl Triflates by Amines or Amides
Authors: TAO Xiaochun , DAI Chunya , CAO Xiongjie , CAI Lisheng , PIKE Victor W. 
Published: March 2009

Abstract Various aryl triflates, bearing ketone or aldehyde groups, were evaluated for palladium‐mediated introduction of an amino group at the triflate position in the presence of various phosphine ligands. BINAP was best for secondary amines, MOP‐type ligand for primary or small secondary amines and Xantphos for primary or cyclic secondary amides. No ligand was found effective for acyclic secondary amides.
Asymmetric Alkynylation of Aldehydes Catalyzed by Bifunctional Zinc(salen) Complex
Authors: SHEN Chun , CHEN Lei , TANG Jie , XU Minghua 
Published: March 2009

AbstractThe asymmetric alkynylation of aldehydes catalyzed by bifunctional Zn(salen) catalyst was realized. With a Kozlowski salen ligand (7e) bearing secondary basic 1‐piperidinylmethyl groups at C‐3 and C‐3′, the enhanced catalytic reactivity and stereoselectivity in comparison with that of normal salen ligands in the alkynylzinc addition to aldehydes were observed.
Controlled Grafting of Poly(methyl methacrylate) Brushes on Poly(vinylidene fluoride) Powders by Surface‐initiated Atom Transfer Radical Polymerization
Authors: TANG Zhaoqi , LI Wei , LIU Lanqin , HUANG Lei , ZHOU Jin , YU Haiyin 
Published: March 2009

AbstractControlled grafting of well‐defined polymer brushes of methyl methacrylate (MMA) on the poly(vinylidene fluoride) (PVDF) powders was carried out by the surface‐initiated atom transfer radical polymerization (ATRP). The ATRP initiator was anchored on the PVDF surface by alkaline treatment, followed by UV‐induced bromination; then methyl methacrylate (MMA) was grafted onto the brominated PVDF by the ATRP technique. The chemical composition changes of PVDF were characterized by Fourier transform‐infrared spectroscopy (FT‐IR) and X‐ray photoelectron spectroscopy (XPS). FT‐IR and XPS results clearly indicated the successful graft of poly(methyl methacrylate) onto the PVDF surface.
Synthesis, Structure and Properties of Poly(arylene imino)s
Authors: ZhANG Lin , CHANG Guanjun 
Published: March 2009

AbstractA series of poly(arylene imino)s (PAI) with high molecular weights and small polydispersity indices have been synthesized by the condensation polymerization of different diiodobenzenes with aromatic primary diiminos via two different methods. Their structures were characterized by means of FT‐IR, 1H NMR spectroscopy and elemental analysis. DSC and TG measurements show that the polymers possess high glass transition temperatures (Tg>150 °C) and good thermal stability with high decomposition temperatures (TD>400 °C). These novel polymers also exhibit good solubility in organic solvents.
Initial report of the cancer Patient‐Reported Outcomes Measurement Information System (PROMIS) sexual function committee
Authors: Jeffery Diana D. , Tzeng Janice P. , Keefe Francis J. , Porter Laura S. , Hahn Elizabeth A. , Flynn Kathryn E. , Reeve Bryce B. , Weinfurt Kevin P. 
Published: March 2009

AbstractFor this report, the authors described the initial activities of the Cancer Patient‐Reported Outcomes Measurement Information System (PROMIS)‐Sexual Function domain group, which is part of the National Institutes of Health Roadmap Initiative to develop brief questionnaires or individually tailored assessments of quality‐of‐life domains. Presented are a literature review of sexual function measures used in cancer populations and descriptions of the domains found in those measures. By using a consensus‐driven approach, an electronic bibliographic search was conducted for articles that were published from 1991 to 2007, and 486 articles were identified for in‐depth review. In total, 257 articles reported the administration of a psychometrically evaluated sexual function measure to individuals who were diagnosed with cancer. Apart from the University of California‐Los Angeles Prostate Cancer Index, the International Index of Erectile Function, and the Female Sexual Function Index, the 31 identified measures have not been tested widely in cancer populations. Most measures were multidimensional and included domains related to the sexual response cycle and to general sexual satisfaction. The current review supports the need for a flexible, psychometrically robust measure of sexual function for use in oncology settings and strongly justifies the development of the PROMIS‐Sexual Function instrument. When the PROMIS‐Sexual Function instrument is available publicly, cancer clinicians and researchers will have another measure with which to assess patient‐reported sexual function outcomes in addition to the few legacy measures that were identified through this review. Cancer 2009. © 2009 American Cancer Society.
Identification and localization of functional subdivisions in the visual cortex of the adult mouse
Authors: van Brussel Leen , Gerits Annelies , Arckens Lutgarde 
Published: March 2009

AbstractWe investigated the anatomical characteristics of the mouse visual system through in situ hybridization for the neuronal activity marker zif268. Our main goal was to delineate the full extent of the cortical region processing visual information and additionally to identify the monocularly and binocularly driven subregions therein. We therefore analyzed the neocortex of monocularly and binocularly enucleated mice versus visually stimulated control mice. These visual manipulations revealed eye‐specific parcellations at the neocortical level. In binocularly enucleated mice we detected an unambiguous lateral border between visually driven and nonvisual cortex based on the clear deprivation‐induced reduction in zif268 expression in the first. However, medially a transition zone of intermediate intensity was found between primarily visual, that is V1 and multimodal retrosplenial cortex. Also in monocularly enucleated mice, the visual cortex contralateral to the deprived eye clearly displayed distinct regions of lower signal than the ipsilateral cortex. Yet interspersed between these regions of basal activity we could clearly identify a zone of high activity spanning the V1‐V2L border. A second zone of higher activity was noticeable near the medial border of visual cortex. Comparison with binocularly enucleated mice indicates the presence of both binocular input as well as nonvisual input in this medial cortical region and thus confirms the transitional nature of the recently described rostromedial areas. J. Comp. Neurol. 514:107–116, 2009. © 2009 Wiley‐Liss, Inc.
Fenestration of the calyx of held occurs sequentially along the tonotopic axis, is influenced by afferent activity, and facilitates glutamate clearance
Authors: Ford Marc C. , Grothe Benedikt , Klug Achim 
Published: March 2009

AbstractThe calyx of Held is a type of giant glutamatergic presynaptic terminal in the mammalian auditory brainstem that transmits afferent information from the cochlear nucleus to the medial nucleus of the trapezoid body (MNTB). It participates in sound localization, a process that requires very high temporal precision. Consistent with its functional role, the calyx shows a number of specializations for temporal fidelity, one of them being the giant terminal itself with its many release sites. During the first 3 weeks of postnatal development, the calyx transforms from a spoon‐shaped, closed morphology to a highly fenestrated open structure. Calyces in Mongolian gerbils (Meriones unguiculatus) were labeled via injection of fluorescent tracers and their morphology was reconstructed at various timepoints during early postnatal development. We show that the fenestration process does not occur simultaneously in all calyces. Calyces transmitting high‐frequency sound information fenestrate significantly earlier than those transmitting low‐frequency information, such that a temporary developmental gradient along the tonotopic axis is established around the time of hearing onset. Animals that were deprived of afferent activity before hearing onset, either via cochlear removal or administration of ototoxic drugs, do not show this developmental gradient. Glial processes containing glutamate transporters occupy the newly created windows in the calyx and thus could augment the fast clearance of neurotransmitter. The physiological consequences of this faster clearance include a faster decay time course of synaptic currents as well as a lower amount of residual current accumulating during the processing of repeated activity such as stimulus trains. J. Comp. Neurol. 514:92–106, 2009. © 2009 Wiley‐Liss, Inc.
Dimension theory of iterated function systems
Authors: Feng De‐Jun , Hu Huyi 
Published: March 2009

AbstractLet {Si} be an iterated function system (IFS) on ℝd with attractor K. Let (Σ, σ) denote the one‐sided full shift over the alphabet {1, …, 𝓁}. We define the projection entropy function hπ on the space of invariant measures on Σ associated with the coding map π : Σ → K and develop some basic ergodic properties about it. This concept turns out to be crucial in the study of dimensional properties of invariant measures on K. We show that for any conformal IFS (respectively, the direct product of finitely many conformal IFSs), without any separation condition, the projection of an ergodic measure under π is always exactly dimensional and its Hausdorff dimension can be represented as the ratio of its projection entropy to its Lyapunov exponent (respectively, the linear combination of projection entropies associated with several coding maps). Furthermore, for any conformal IFS and certain affine IFSs, we prove a variational principle between the Hausdorff dimension of the attractors and that of projections of ergodic measures. © 2008 Wiley Periodicals, Inc.
Eating disorders in adolescents and their repercussions in oral health
Authors: Ximenes Rosana , Couto Geraldo , Sougey Everton 
Published: March 2009

AbstractObjective:To examine the prevalence of oral alterations related to eating disorders and associated factors.Method:A cross‐sectional study including 650 adolescents aged from 12 to 16 was carried out through self‐report questionnaires (EAT‐26; BITE and self‐rating hamilton depression questionnaire, SRHDQ) and dental examination.Results:Significant associations were observed in mucositis, cheilitis, hypertrophy of salivary glands, and dental erosions. The prevalence of adolescents at risk for eating disorders was of 33.1%, according to EAT‐26 and 1.7% (high scores) and 36.5% (medium scores), in BITE, higher among 13‐year‐old females, with brothers, parents or responsible person who are illiterate, being the youngest child, living in a residence of at most two rooms and who showed depressive symptoms. All these factors showed significant relation to eating disorders.Discussion:Presence of oral alterations is associated to symptoms of eating disorders, helping precocious detection of sub clinical cases. © 2009 by Wiley Periodicals, Inc. Int J Eat Disord 2010
Use of extreme weight‐control behaviors in the absence of binge eating with and without subjective bulimic episodes: A community‐based study
Authors: Mond Jonathan M. , Hay Phillipa J. 
Published: March 2009

AbstractBackground and Methods:In a community sample of women who reported the use of extreme weight‐control behaviors in the absence of binge eating, subgroups of participants who reported (n = 23) and who did not report (n = 42) recurrent subjective bulimic episodes (SBEs) were compared on a range of outcomes, including current levels of eating disorder and comorbid psychopathology.Results:Participants who reported SBEs had higher levels of eating disorder psychopathology, impairment in role functioning, and general psychological distress, than those who did not. Scores on these measures among participants who reported SBEs were similar to those of eating disorder patients receiving specialist treatment, whereas those of participants who did not have recurrent SBEs tended to be intermediate between eating disorder patients and healthy women.Discussion:The findings are consistent with the hypothesis that it is the combination of SBEs and extreme weight‐control behaviors, rather than extreme weight‐control behaviors per se, that indicates clinical significance. © 2009 by Wiley Periodicals, Inc. Int J Eat Disord 2010