bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photochromism of Thiazole‐Containing Triangle Terarylenes
Authors: Nakashima Takuya , Atsumi Kazuhiko , Kawai Shigekazu , Nakagawa Tetsuya , Hasegawa Yasuchika , Kawai Tsuyoshi 
Published: May 2007

AbstractTriangle terarylene derivatives based on the 4,5‐diarylthiazole structure have been synthesized and their photochromic properties have been studied both in solution and in the crystalline state. The thiazolyl‐substituted terarylenes displayed reversible photochromism in solution, with photocyclization quantum yields as high as 60 %, while a 4,5‐dithienylthiazole derivative underwent photochromic reaction even in the single‐crystal state, although a 4,5‐dithiazolylthiazole (terthiazole) showed no photochromic reaction in the crystalline phase. The difference in photochromic reactivity between the 4,5‐dithienylthiazole and the 4,5‐dithiazolylthiazole was found by X‐ray crystallographic analyses to originate from conformational differences in the crystalline state. The thermal cycloreversion activation energies in the solution phase were measured for thiazolyl‐substituted terarylenes and for a corresponding terthiophene derivative. The activation energy for the transition from photogenerated closed‐ring isomer to open‐ring isomer increased with the number of substitutions of thiazole unit for thiophene. The lower aromatic stabilization energy of thiazole in relation to that of thiophene was considered to be responsible for the thermal stability of the closed‐ring isomers of thiazolyl‐substituted terarylenes.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
New Amino Endoperoxides Belonging to the Antimalarial G‐Factor Series
Authors: Givelet Cécile , Bernat Virginie , Danel Mathieu , André‐Barrès Christiane , Vial Henri 
Published: May 2007

AbstractIn the search for new antimalarial endoperoxides we developed a direct route for the preparation of new amino compounds belonging to the G‐factor series. During the synthesis, a significant difference in reactivity between two series of diastereoisomers was observed. The final amino endoperoxides were obtained with 58 to 70 % yields, depending on the starting amine, in the “anti” series, but with the “syn” diastereoisomers an unexpected rearrangement occurred during the deprotection step. This was attributed to a transient hexacoordinate fluorosilicon complex allowing the formation of a 1,2‐dioxetane. Its decomposition gave aldehyde 12 and 4‐hydroxybutan‐2‐one; these compounds were also identified when acidic conditions were used in the deprotection step. The anti amino compounds obtained were tested, but in vitro activities were found to be lower than initially expected, and fitted poorly with the previous biological hypothesis.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Electroanalytical Determination of Lidocaine in Pharmaceutical Preparations Using Boron‐Doped Diamond Electrodes
Authors: Oliveira Robson T. S. , Salazar‐Banda Giancarlo R. , Ferreira Valdir S. , Oliveira Silvio C. , Avaca Luis A. 
Published: May 2007

AbstractA new electroanalytical procedure was developed for the determination of lidocaine in commercial local anesthetics products containing lidocaine as the active ingredient. The procedure is based on the use of electrochemical methods as cyclic and square‐wave voltammetry, with boron‐doped diamond electrodes. The oxidation of lidocaine in Britton–Robinson buffer (0.1 mol L−1) using this type of electrode gives rise to one irreversible peak in 1.68 V (versus Ag/AgCl). The detection and quantification limits obtained from pure water were 10.0 and 34.4 μg/L, respectively. The proposed electrochemical method was also successfully applied to the analysis of commercially available pharmaceutical preparations. The electrochemical responses of pharmaceutical preparations (gels) were identical to those of standard lidocaine. No influence of propyleneglycol present in the gels on the voltammetric responses was observed. Lidocaine recoveries ranged from 97.6% to 99.2%.
A Potentiometric Stripping Analyzer for Multianalyte Screening
Authors: Adami Manuela , Marco Sartore , Nicolini Claudio 
Published: May 2007

AbstractThe paper describes a simple and low‐cost multisensing instrument based on neural network to monitor multiple environmentally significant metals in solution by implementing the potentiometric stripping analysis technique. Our analyzer consists of a measuring unit, implemented on a lap‐top/notebook computer equipped with a simple electronic circuitry, and a reusable sensor, based on glassy‐carbon technology. The current system has been characterized with synthetic samples containing different concentrations of lead, copper, cadmium and zinc, showing detection limits suitable for the first monitoring of metal traces. A linear relationship between peak area and concentration has been observed for all tested metals. Therefore, a simple linear regression can be used by the analyzer to determine the actual metal concentration from the PSA peak area. The presence of a second metal or of a real matrix, often, interferes with stripping measurements in different ways: compounds with oxidation potentials close to that of the analytes of interest may interfere if the instrument does not have sufficient resolution to resolve the overlapping PSA peaks; species which form intermetallic compounds with the analytes may result in erroneously low analyte concentration readings, since the oxidation potential of the intermetallic compound is rarely near that of the original analyte. In order to overcome these problems, the described analyzer has been integrated with a Neural Network algorithm, able to separate the different contributions, after a proper training.
Design and Development of Imprinted Polymer Inclusion Membrane‐Based Field Monitoring Device for Trace Determination of Phorate (O,O‐Diethyl S‐Ethyl Thiomethyl Phophorodithioate) in Natural Waters
Authors: Prasad Karamala , Prathish Krishnapillai Padmajakumari , Gladis Joseph Mary , Naidu Gurijala Ramakrishna , Rao Talasila Prasada 
Published: May 2007

AbstractA biomimetic potentiometric field monitoring device was developed for the trace determination of phorate (O,O‐diethyl S‐ethyl thiomethyl phophorodithioate) in natural waters. The sensing element was fabricated by the inclusion of phorate imprinted polymer materials in the polyvinyl chloride (PVC) matrix. The sensor surface can be reused without conditioning unlike most other conventional sensors. Operational parameters such as amount and nature of plasticizers sensing material, pH and response time were optimized. The response characteristics of the non‐imprinted (NIPIM) and imprinted polymer inclusion membrane (IPIM) sensors for phorate were compared under optimum conditions. The IPIM sensor responds linearly to phorate in the concentration in the ranges 1×10−9 to 1×10−6 M and 1×10−6 to 1×10−5 M of different slopes with a detection limit of 1×10−9 M. The selectivity was tested with various common organophosphorous (OP) pesticides and herbicides. In addition to superior sensitivity and selectivity of IPIM over NIPIM‐based sensor, IPIM‐based phorate sensor was found to be stable for 3 months and can be used for more than 40 times without any loss in sensitivity. The applicability for analyzing ground, river and tap‐water samples was successfully demonstrated via recovery studies.
Quantized Double‐Layer Charging of Iron Oxide Nanoparticles on a‐Si:H Controlled by Charged Defects in a‐Si:H
Authors: Weis Martin , Gmucová Katarína , Nádaždy Vojtech , Capek Ignác , Šatka Alexander , Kopáni Martin , Cirák Július , Majková Eva 
Published: May 2007

AbstractSequential single‐electron charging of iron oxide nanoparticles encapsulated in oleic acid/oleyl amine envelope and deposited by the Langmuir‐Blodgett technique onto Pt electrode covered with undoped hydrogenated amorphous silicon film (a‐Si:H) is reported. Quantized double‐layer charging of nanoparticles is detected by cyclic voltammetry as current peaks and the charging effect can be switched on/off by the excess of negative/positive charged defect states in the a‐Si:H layer. The particular charge states in a‐Si:H are created by the simultaneous application of a suitable bias voltage and illumination before the measurement.
Performance‐based seismic bridge design for damage and loss limit states
Authors: Mackie K. R. , Stojadinović B. 
Published: May 2007

AbstractRecent efforts in the earthquake engineering community have focused largely on developing a performance‐based earthquake engineering assessment methodology. However, equally important is applying such a methodology to the design of structures. Probabilistic performance‐based seismic design enables design and acceptance criteria to be specified by a continuum of limit states and incorporates uncertainty in all the sources of data. This paper introduces a non‐iterative method, based on the Pacific Earthquake Engineering Research Center framework, for design of bridge structures in terms of single or multiple physical design parameters, such as column height and diameter. Design parameter solutions are obtained from explicit consideration of uncertainty in the hazard, demand, damage, and loss to the structure by way of specifying a level of confidence in the resulting design under different performance objectives. Similar to other performance‐based methodologies, performance objectives consist of a performance level and a hazard level. Design equations are derived for performance levels defined in terms of bridge damage and loss. Examples are presented of both univariate and bivariate design parameter cases for typical reinforced concrete highway overpass bridges in California. Copyright © 2007 John Wiley & Sons, Ltd.
Impact of personality on termination of short‐term group psychotherapy in depressed elderly outpatients
Authors: Canuto Alessandra , Meiler‐Mititelu Corina , Herrmann François , Giannakopoulos Panteleimon , Weber Kerstin 
Published: May 2007

AbstractObjectiveTermination in group psychotherapy is an essential phase of the psychotherapeutic process, yet its clinical determinants remain largely unknown, especially in elderly patients. The aim of this study was to assess how patients' personality traits influence their way of leaving a short‐term psychotherapy group as well as a larger therapeutic community program.MethodPersonality traits were assessed with the NEO Five‐Factor Inventory in 24 elderly depressed outpatients. Patients' terminations from the group as well as from the community were ranked into four classes according to their appropriateness (completeness of experience and ability to deal with feelings of separation).ResultsNeuroticism was not related to the quality of termination. In contrast, agreeableness and openness to experience were strongly associated with successful termination. Conscientiousness and extraversion may have a differential impact depending on the type of group (group psychotherapy versus therapeutic community).ConclusionPersonality traits may be important clinical determinants of the quality of termination process in both group psychotherapy and therapeutic community settings for elderly depressed patients. Copyright © 2007 John Wiley & Sons, Ltd.
A methodological and operative framework for the evaluation of an e‐health project
Authors: Buccoliero Luca , Calciolari Stefano , Marsilio Marta 
Published: May 2007

AbstractAssessing public sector ICT investments represents the premise for successful implementation of an e‐health strategy. The recent literature stresses the importance of going beyond the mere financial and/or technical dimensions of the analysis. Consequently, the paper proposes an example of e‐health project evaluation aiming to develop measures which get close to the notion of benefits to the different stakeholders involved: top management, patients, local community. The case study refers to an Italian health care organization that implemented a project of digitalization of its clinical reports production few years ago. Based on on‐field research, different approaches are used to assess costs and benefits from different stakeholders' perspectives. The results of a multidimensional evaluation are reported to emphasize the need for different measures to assess the sustainability of an e‐health project according to the financial convenience, the social role of the organization, and the contingent situation. Copyright © 2007 John Wiley & Sons, Ltd.
Financial profiling of public hospitals: an application by data mining
Authors: Ozgulbas Nermin , Koyuncugil Ali Serhan 
Published: May 2007

AbstractThis paper presents an application of the data mining method to determine the financial profiles of the public hospitals in Turkey. The study is based on the data compiled in 2004, covering 645 public hospitals run by the Ministry of Health (MoH) as the main provider of primary and secondary health services in Turkey. The public hospitals, currently financed by a mixture of funds allocated from the general budget and individually operated revolving funds, need urgent solutions to their financial problems as a part of an ongoing national reform effort. The analysis adopts the Chi‐Square Automatic Interaction Detector (CHAID) decision tree algorithm, as one of the most efficient and up‐to‐date data mining method used for segmentation.The study has found that the public hospitals could be categorized by the CHAID into 12 different profiles in terms of their financial performance. These profiles have guided us in determining the key financial indicators to be focused upon in the public hospitals and present best practices to improve their respective financial performances. The findings have also allowed policy suggestions as to the financial strategies that may be considered in improving the financial performance of the public hospitals toward a successful health sector reform in Turkey. Copyright © 2007 John Wiley & Sons, Ltd.
Template‐directed patterning of polymers and biomaterials
Authors: Chandekar Amol , Sengupta Sandip K. , Whitten James E. 
Published: May 2007

AbstractA novel method of patterning surfaces with synthetic or biological polymers is demonstrated. It consists of using microcontact printing to pattern a gold surface with an adsorbate that imparts hydrophilicity; the remainder of the surface is covered with one that imparts hydrophobicity. 16‐Mercaptohexadecanoic acid (MHDA) and 1H,1H,2H,2H‐perfluorodecanethiol, respectively, have been used as the hydrophilic and hydrophobic adsorbates. This functionalized gold surface then serves as a template for patterning hydrophilic polymers and biomaterials, which are either spin‐coated or drop‐cast onto the surface. Using this methodology, it is shown by atomic force microscopy, scanning electron microscopy (SEM), and fluorescence microscopy that micron‐scale patterns of a poly(ethylene)‐block‐poly(ethylene oxide) copolymer, poly‐L‐tryptophan, and bovine collagen can be fabricated, with these mimicking the MHDA patterns. For the block copolymer, it is found by atomic force microscopy that the heights of the polymer patterns decrease as their widths decrease. This is believed to be due to the inherent instability of tall, narrow polymer structures and the tendency of the polymer to minimize its exposed surface area. For poly‐L‐tryptophan, two different molecular weights of this polyamino acid have been studied, and different morphologies within the patterned regions are observed. While oligomeric poly‐L‐tryptophan (1,000–5,000 g/mol) gives smooth MHDA‐covered patterns, the higher molecular weight (15,000–50,000 g/mol) yields fibrous ones. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
AFM studies of nanoparticle deposition via electrospray ionization
Authors: Therrien Joel , Dindar Amir , Smith David 
Published: May 2007

AbstractElectrospray ionization was used to deposit CdSe nanoparticles on graphite and InP substrates. The charge transferred to the substrate via the deposition was correlated to the number of particles found on the substrate by AFM observation. A charge per nanoparticle was determined from depositions of various lengths of time, which is ∼1 electron per nanoparticle. This value was found to be consistent for concentrations of nanoparticle solutions, which differed by an order of magnitude. Such a value may be used for predicting the density of nanoparticles deposited on a substrate during the deposition. It was found that above a critical concentration, the deposition process produced large clumps of particles rather than individual particles. At lower concentrations, individual particles deposited on the graphite substrates were found to be mobile, arranging themselves on step edges of the graphite. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Nanoparticle scanning and detection on flat and structured surfaces using fluorescence microscopy
Authors: Guldiken Rasim , Makaram Prashanth , Bakhtari Kaveh , Park Jingoo , Busnaina Ahmed A. 
Published: May 2007

AbstractA new technique is proposed for the scanning and detection of nanoparticles on flat substrates and three‐dimensional structures using fluorescence microscopy. This technique is utilized for particle removal measurements especially in semiconductor and hard disk manufacturing. This fluorescent particle scanning technique enables nanoscale particle detection. The technique shows that single particles down to 63 nm could be detected and counted. The technique is also capable of detecting particles in trenches that are as deep as 500 μm. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Surviving the years of infancy: longevity among small firms in Nigeria, 1971–1997
Authors: Sam Monibo A. 
Published: May 2007

AbstractIt is widely believed that a common pattern exists in the closure of small firms in Africa. Typically, these firms are reported to die in their first three years of life. Like any generalisation, this view fails to take into account probable variations across segments of the small business sector. A few recent reports on small firms in Nigeria and in southern Africa draw attention to this limitation. In this paper, we draw on the experience of privately incorporated firms in Nigeria to report a closure pattern that diverges significantly from that of the sector generally. Our finding that only a small fraction of the closures occurred in the infancy of the firms has implication for research and policy on small businesses. Copyright © 2007 John Wiley & Sons, Ltd.
TFP growth and resource allocation in Singapore, 1965–2002
Authors: Akkemik K. Ali 
Published: May 2007

AbstractThis paper investigates the impact of the reallocations of resources across manufacturing industries on aggregate manufacturing TFP growth in Singapore for the period 1965–2002. This is done by decomposing aggregate TFP growth into its sources, TFP growth arising from within individual industries and from the reallocations of capital and labour. The results show that TFP growth was negative before 1985 but improved remarkably to positive figures after 1985. Resource reallocations are found to account for a large portion of this improvement in aggregate TFP growth. Copyright © 2007 John Wiley & Sons, Ltd.
Evaluation of Endothelial Cell Adhesion onto Different Protein/Gold Electrodes by EIS
Authors: Bouafsoun Amira , Helali Saloua , Othmane Ali , Kerkeni Abdelhamid , Prigent Anne‐France , Jaffrézic‐Renault Nicole , Bessueille François , Léonard Didier , Ponsonnet Laurence 
Published: May 2007

AbstractTo study cell attachment to biomaterials, several proteins such as fibronectin, collagen IV, heparin, immunoglobulin G, and albumin have been deposited onto polystyrene adsorbed on a self‐assembled monolayer (silane or thiol) on glass or gold, respectively. The different steps of this multilayer assembly have been characterized by electrochemical impedance spectroscopy (EIS). These data are compared to those of adhesion rate, viability percentage, and cytoskeleton labeling for a better understanding of the cell adhesion process to each protein. All the proteins are endothelial cell adhering biomolecules but not with the same features. A linear relationship has been established between adhesion rate and resistance of the endothelial cell/protein interface for all negatively charged proteins.magnified image
A Micro/Nanoscale Surface Mechanical Study on Morpho‐Functional Changes in Multilineage‐Differentiated Human Mesenchymal Stem Cells
Authors: Danti Serena , D'Acunto Mario , Trombi Luisa , Berrettini Stefano , Pietrabissa Andrea 
Published: May 2007

AbstractIn recent years MSCs have become a very attractive tool in tissue engineering and regenerative medicine because of their ability to be committed along several lineages through chemical or physical stimuli. Nevertheless their therapeutic potential and plasticity are not yet totally understood. This report describes the use of AFM together with conventional microscopies to obtain mechanical information on cell surfaces and deposited extra cellular matrix molecules, after inducing the differentiation of human MSCs towards three typical mesoderm phenotypes. The aim is to correlate morphological, functional, and mechanical aspects of human MSCs to obtain a deeper understanding of their great potential.magnified image
Chitosan Based Hydrogel Microspheres as Drug Carriers
Authors: Vodná Lucia , Bubeníková Silvia , Bakoš Dušan 
Published: May 2007

AbstractChitosan/tripolyphosphate (CHIT/TPP) and chitosan/tripolyphosphate/chondroitin sulfate (CHIT/TPP/CHS) core‐shell type microspheres were prepared by polyelectrolyte complexation in order to develop a biocompatible matrix for drug delivery. The continual method using a multi‐loop reactor under sterile conditions was applied for microsphere preparation. All the types of microspheres produced were spherical in shape and had a porous structure. The mechanical resistance of the microspheres increased in the presence of CHS as the second polyanion, which toughened the microsphere shell structure. For a drug release application, the process of microsphere preparation was modified by dissolving ofloxacin (OFL), the fluoroquinolone antibiotic, in CHIT solution before complex formation. This study shows the difference in OFL release comparing the microspheres CHIT/TPP and CHIT/TPP/CHS and implies the potential to control this process.magnified image
Macromolecular Biomaterials for Scaffold‐Based Vascular Tissue Engineering
Authors: Couet Frédéric , Rajan Navneeta , Mantovani Diego 
Published: May 2007

AbstractCardiovascular diseases are increasingly becoming the main cause of death all over the world, which has led to an increase in the economic and social burden of such diseases. Vascular tissue engineering (VTE) is providing a route towards interesting applications, mainly focussing on the in vitro, in vivo, or combined in vitro/in vivo regeneration of small‐diameter blood vessels (<6 mm) for coronary or peripheral vascular substitutions. Although different approaches have been investigated in the past two decades to achieve this aim, the most common method uses a macromolecular‐based structure to scaffold cells during the regeneration process. Therefore, the aim of this work is to comprehensively review macromolecular biomaterials that were designed, developed, fabricated, and tested for scaffolding VTE. In an effort to provide a comprehensive overview, this review will mainly focus on the mechanical properties of the construct and its biological performance that results from the scaffold colonization during cell growth.magnified image