bluuebunny/crossref_metadata_2025_split huggingface dataset:
Releasing polyacrylonitrile from poor biodegradability by insertion of a highly biodegradable chemical structure into the main chain
Authors: Kawabata Nariyoshi , Ohashi Kenji , Nishiyama Takeshi 
Published: November 2005

AbstractPolyacrylonitrile turned biodegradable by incorporation of N‐benzyl‐4‐vinylpyridinium chloride (BVP), a highly biodegradable chemical structure, into the main chain. Oligomers of acrylonitrile are biodegradable dissimilar to polyacrylonitrile, and connection of them by BVP produced biodegradable polymers. The half‐life of a copolymer of acrylonitrile with BVP (PAN‐co‐BVP) in a molar ratio of 97 : 3 was 21 days when treated with activated sludge in soil. The average number of acrylonitrile units in the oligo‐acrylonitrile portion was 32. Degradation at the BVP portion appeared predominant, but the oligo‐acrylonitrile portion also underwent exhaustive degradation when the portion was sufficiently short. Even though biodegradable, oligo‐acrylonitriles are not useful as polymeric materials, but connection of them by BVP produces useful polymeric materials possessed of sufficient biodegradability. Such bridged polymer is different from conventional polyacrylonitrile, and its utility may be different to some extent, but it possesses sufficient biodegradability. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 852–857, 2006
Preparation and properties of polyimide nanocomposites via a soluble polyisoimide precursor
Authors: Oh Seung Bae , Kim Young Jun , Kim Ji Heung 
Published: November 2005

AbstractA polyisoimide based on 4,4′‐oxydiphthalic dianhydride and 4,4′‐oxydianiline was synthesized and used for the preparation of nanocomposites with commercial organoclays by the solution dispersion technique. The cast composite films were heat‐treated to convert them into polyimide nanohybrid films. Homogeneous dispersions were obtained at lower clay concentrations (<5 wt %), and this was confirmed by X‐ray diffraction and transmission electron microscopy. The nanocomposites displayed improved thermal and mechanical properties. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 869–874, 2006
Morphology and mechanical properties of blends of thermoplastic polyurethane and polyolefins
Authors: Di Yali , Kang Maoqing , Zhao Yuhua , Yan Shirun , Wang Xinkui 
Published: November 2005

AbstractPolyolefins (PO) were melt mixed with thermoplastic polyurethane (TPU) in a 20 : 80 weight ratio with or without compatibilizer containing 0.5 wt % of maleic anhydride. Effects of component viscosities on morphology and on mechanical properties of the blend were studied by scanning electron microscope (SEM), tensile property analysis, and dynamic mechanical analysis (DMA). It was found that the disperse particle size of compatibilizer‐free blends decreased with the decreasing viscosity ratio of the disperse phase to TPU. The efficiency of the compatibilizer in reducing the particle size varied with viscosity ratios of the disperse phase to compatibilizer. However, the particle size did not decrease with the decreasing viscosity ratio monotonically. With lower viscosity ratio, addition of 5 wt % compatibilizer resulted in a greater reduction of particle size and less loss in the tensile properties as compared to the TPU matrix. For the polyethene (PE) that has the lowest viscosity value among all the POs, its size in the blend was stabilized with the addition of compatibilizer and no compatibilization was detected by DMA and by tensile property analysis. The mobility of the disperse phase and compatibilizer and the dispersion competition between them seemed important. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 875–883, 2006
New Agents with Antimycobacterial Activity
Authors: Marco‐Contelles José , Gómez‐Sánchez Elena 
Published: November 2005

AbstractIn this paper, we report that a series of structurally simple a‐halogenoacetamides (1–8) show potent and excellent antimycobacterial activities against drug‐sensitive Mycobacterium tuberculosis H37Rv and drug‐resistant M. avium.
Synthesis of 5,6‐Dimethyl‐9‐methoxy‐1‐phenyl‐6H‐pyrido[4,3‐b]carbazole Derivatives and their Cytotoxic Activity
Authors: Jasztold‐Howorko Ryszard , Pelczynska Marzena , Nasulewicz Anna , Wietrzyk Joanna , Opolski Adam 
Published: November 2005

AbstractStarting from 2‐(6‐methoxy‐1‐methyl‐9H‐carbazol‐2‐yl)ethylamine 7 and mixed anhydrides of 4‐nitrobenzoic acid or 4‐methoxybenzoic acid, the corresponding 5,6‐dimethyl‐9‐methoxy‐1‐(4‐substituted phenyl)‐6H‐pyrido[4,3‐b]carbazoles 11a–b, 5,6‐dimethyl‐9‐hydroxy‐1‐(4‐substituted phenyl)‐6H‐pyrido[4,3‐b]carbazoles 12a, 12c, and their quaternary salts 13a–d were obtained. The four new pyridocarbazole derivatives 12a–c and 13d satisfy the international activity criterion for synthetic compounds, namely an ID50 value lower then 4 μg/mL in preliminary in vitro cytotoxic activity screening against the A549 cell line (non‐small cell lung cancer).
Stereoisomers of Compounds with Symmetric Constitutions
Authors: Siebert Carsten D. , Tampe Niels 
Published: November 2005

AbstractChiral organic compounds with unsymmetric constitutions can lead to Nr = 2n stereoisomers. By contrast, if a chiral compound has a symmetric constitution, then the number of stereoisomers is reduced [1]. In this publication, we wish to present an algorithm to calculate the number of stereoisomers of chiral organic compounds of the latter type (e. g. sugar acids). The first step is the development of two different functions for unbranched compounds where the number of repeating units is even or uneven. Other stereogenic units like double bonds, chiral axes or planes are not discussed. The results are then checked against the actual isomers. The next step leads to a unified equation to predict the precise number of stereoisomers that can exist. Thus, the relationship between chirality and symmetry is shown in detail. Additionally, the algorithm is applied to some drug molecules with symmetric constitutions.
Synthesis and Antiplatelet Activity of New Imidazole‐4‐Carboxylic Acid Derivatives
Authors: Rehse Klaus , Steege Jens 
Published: November 2005

Abstract1‐Arylalkyl‐5‐phenylsulfonamino‐imidazole‐4‐carboxylic acid esters and their carboxamides with an additional secondary amino group were synthesized and identified as antiplatelet agents in a low micromolar range (Born‐test, inducer collagen). To describe the mechanism of action more precisely the Born‐test was carried out as well with ADP, adrenaline or PAF, respectively. In addition, two compounds were investigated for their COX‐1 inhibitory activities. Provided the essential structural criteria are met i.e. amide group or ester, sulfonylamino rest, hydrophobic moieties, and a secondary amino function, slight structural modifications are able to shift the pattern of activity among the above platelet receptors. So, the ester 5c exhibits PAF antagonistic activity at IC50 = 1 μM and COX‐1 inhibition (IC50 = 0.4 μM). The carboxamide 6c shows ADP antagonistic properties (IC50 = 2 μM). Compound 6g is as well PAF antagonistic (IC50 = 4 μM) and a COX‐1 inhibitor (IC50 = 1 μM). The derivative 6i shows a strong antiadrenergic (IC50 = 0.15 μM) and PAF antagonistic (IC50 = 0.66 μM) effect.
New Pyrimido[5,4‐c]cinnolines with Antiplatelet Activities
Authors: Rehse Klaus , Gonska Hedwig 
Published: November 2005

AbstractTwenty one new pyrimido[5,4‐c]cinnolines containing different lipophilic moieties (viz. phenyl, 4‐methoxyphenyl, 2‐furanyl, 2‐thienyl) in position 2 and additional basic groups (e.g., alkylaminopropyl, dialkylaminopropyl and cyclohexylaminopropyl) in position 4 of the title ring system have been prepared and investigated for antiplatelet effects (Born test). Ten of them inhibited the platelet aggregation induced by collagen with an IC50 below 10 μmol/L (6a, 6b, 6c, 6g, 6h, 6i, 6k, 6m, 6q, 6u). A closer inspection of the antiplatelet effect with other inducers showed antagonism against adrenaline (6m), ADP antagonist (6i) and PAF antagonist activities (6m, 6i, 6u) in nanomolar (IC50) concentration ranges.
Synthesis and Anti‐HCMV Activity of Novel 5′‐Norcarboacyclic Nucleosides
Authors: Kim Aihong , Hong Joon Hee 
Published: November 2005

AbstractA very simple route for synthesizing a novel carboacyclic version of 5¢‐noraristeromycin is described. Condensation of the mesylates 9 and 23 with the natural nucleosidic bases (A, U, T, C) under standard nucleophilic substitution (K2CO3, 18‐Crown‐6, DMF) and deblocking conditions, afforded the target nucleosides 14, 15, 16, 17, 28, 29, 30, and 31. In addition, these compounds were evaluated for their antiviral properties against various viruses.
Word sense disambiguation by selecting the best semantic type based on Journal Descriptor Indexing: Preliminary experiment
Authors: Humphrey Susanne M. , Rogers Willie J. , Kilicoglu Halil , Demner‐Fushman Dina , Rindflesch Thomas C. 
Published: November 2005

AbstractAn experiment was performed at the National Library of Medicine® (NLM®) in word sense disambiguation (WSD) using the Journal Descriptor Indexing (JDI) methodology. The motivation is the need to solve the ambiguity problem confronting NLM's MetaMap system, which maps free text to terms corresponding to concepts in NLM's Unified Medical Language System® (UMLS®) Metathesaurus®. If the text maps to more than one Metathesaurus concept at the same high confidence score, MetaMap has no way of knowing which concept is the correct mapping. We describe the JDI methodology, which is ultimately based on statistical associations between words in a training set of MEDLINE® citations and a small set of journal descriptors (assigned by humans to journals per se) assumed to be inherited by the citations. JDI is the basis for selecting the best meaning that is correlated to UMLS semantic types (STs) assigned to ambiguous concepts in the Metathesaurus. For example, the ambiguity transport has two meanings: “Biological Transport” assigned the ST Cell Function and “Patient transport” assigned the ST Health Care Activity. A JDI‐based methodology can analyze text containing transport and determine which ST receives a higher score for that text, which then returns the associated meaning, presumed to apply to the ambiguity itself. We then present an experiment in which a baseline disambiguation method was compared to four versions of JDI in disambiguating 45 ambiguous strings from NLM's WSD Test Collection. Overall average precision for the highest‐scoring JDI version was 0.7873 compared to 0.2492 for the baseline method, and average precision for individual ambiguities was greater than 0.90 for 23 of them (51%), greater than 0.85 for 24 (53%), and greater than 0.65 for 35 (79%). On the basis of these results, we hope to improve performance of JDI and test its use in applications.
Moderating information and communication technologies' influences on socioeconomic development with good governance: A study of the developing countries
Authors: Meso Peter , Datta Pratim , Mbarika Victor 
Published: November 2005

AbstractWith the increasing globalization of the world economy, there has been a growing interest in the potential contributions of good governance to accelerating the rate of economic and social development in the developing countries, and enhance their smooth integration into the emerging global economy. Simultaneously, developed economies are experiencing an increasing proportion in the contribution of knowledge, information, and telecommunication sectors to their overall gross domestic product. This is placing increased focus on the role and contribution of national information infrastructure to economic productivity, and in extension, to the economic and social development of nations. In this article, the authors explore the link between information and communication technologies (ICTs), governance, and social economic development in the developing countries. They empirically conclude that contributions of ICTs to social–economic development are influenced by sociopolitical governance—leading to national development through more prudent and egalitarian application and use of the ICTs' portfolio. The contingent role of governance on ICTs and national development paves the path towards recognizing the importance of sociopolitical moderators.
Identifying a better measure of relatedness for mapping science
Authors: Klavans Richard , Boyack Kevin W. 
Published: November 2005

AbstractMeasuring the relatedness between bibliometric units (journals, documents, authors, or words) is a central task in bibliometric analysis. Relatedness measures are used for many different tasks, among them the generating of maps, or visual pictures, showing the relationship between all items from these data. Despite the importance of these tasks, there has been little written on how to quantitatively evaluate the accuracy of relatedness measures or the resulting maps. The authors propose a new framework for assessing the performance of relatedness measures and visualization algorithms that contains four factors: accuracy, coverage, scalability, and robustness. This method was applied to 10 measures of journal–journal relatedness to determine the best measure. The 10 relatedness measures were then used as inputs to a visualization algorithm to create an additional 10 measures of journal–journal relatedness based on the distances between pairs of journals in two‐dimensional space. This second step determines robustness (i.e., which measure remains best after dimension reduction). Results show that, for low coverage (under 50%), the Pearson correlation is the most accurate raw relatedness measure. However, the best overall measure, both at high coverage, and after dimension reduction, is the cosine index or a modified cosine index. Results also showed that the visualization algorithm increased local accuracy for most measures. Possible reasons for this counterintuitive finding are discussed.
Tragwerke aus Textilbeton – Berechnungsmodelle, Anwendungen
Authors: Möller Bernd , Graf Wolfgang , Hoffmann Andreas , Sickert Jan‐Uwe , Steinigen Frank 
Published: November 2005

AbstractTragwerke mit Bewehrung aus textilen Gelegen sind eine innovative Entwicklung im Bauwesen. Die in Feinbeton eingebettete textile Bewehrung kann für Neubauteile und nachträgliche Verstärkungen verwendet werden. Für Tragwerke aus Textilbeton werden im Beitrag Berechnungsmodelle und Anwendungsbeispiele vorgestellt, die im Sonderforschungsbereich 528 entstanden. Ein besonderer Akzent wird durch die verallgemeinerte Behandlung unscharfer Daten gesetzt, da Datenunschärfe signifikanten Einfluß auf die Systemantworten hat.
Tragfähigkeitsuntersuchungen der Natursteinmauerwerkstützen des Berliner Olympiastadions
Authors: Schlegel Roger , Rautenstrauch Karl , Auberg Rainer 
Published: November 2005

AbstractBei der Modernisierung bzw. Instandsetzung baulicher Anlagen stellt sich häufig die Frage nach der tatsächlichen Tragfähigkeit der bestehenden Bauteile und dem damit im Zusammenhang stehenden Umfang erforderlicher Verstärkungs‐ und Sanierungsmaßnahmen. Für eine sinnvolle und wirtschaftliche Planung kann daher die Qualität und die Realitätsnähe der Bestimmung von Tragfähigkeit und Gebrauchstauglichkeit eine große Bedeutung erlangen. Der Einsatz herkömmlicher, einfacher Ingenieurmodelle stößt dabei mit zunehmender Komplexität der Struktur sehr schnell an Grenzen und kann zu unwirtschaftlichen Ergebnissen führen.Der vorliegende Beitrag zeigt am Beispiel der Natursteinmauerwerkstützen des Berliner Olympiastadions einen Weg, die Tragfähigkeit einer bestehenden Mauerwerkstruktur durch die Kombination von gezielter Zustandsaufnahme sowie Materialprüfung mit modernen, vorwiegend zerstörungsfreien Prüfmethoden und dem Einsatz eines darauf abgestimmten, leistungsfähigen und wirklichkeitsnahen Berechnungsmodells zuverlässig bestimmen zu können. Dabei zeigt sich, daß die realitätsnahe rechnerische Bewertung der Versagenslast und der zugehörigen Versagensmechanismen die Einbeziehung des nichtlinearen Spannungs‐Verformungsverhaltens des Mauerwerks erforderlich macht. Das nichtlineare Materialverhalten wurde mit einem in das Finite‐Element‐Programm ANSYS® implementierten elastoplastischen 3D‐Materialmodell für Mauerwerk erfaßt. Damit wurde es möglich, den Spannungs‐ und Verformungszustand der Mauerwerkstruktur sehr realitätsnah abzubilden und die Standsicherheit sowie die Gebrauchstauglichkeit der Stützenstruktur unter Einbeziehung der Lastgeschichte plausibel nachzuweisen.
In vitroinhibitory effects of non‐steroidal anti‐inflammatory drugs on 4‐methylumbelliferone glucuronidation in recombinant human UDP‐glucuronosyltransferase 1A9—potent inhibition by niflumic acid
Authors: Mano Yuji , Usui Takashi , Kamimura Hidetaka 
Published: November 2005

AbstractThe inhibitory potencies of non‐steroidal anti‐inflammatory drugs (NSAIDs) on UDP‐glucuronosyltransferase (UGT) 1A9 activity were investigated in recombinant human UGT1A9 using 4‐methylumbelliferone (4‐MU) as a substrate for glucuronidation. 4‐MU glucuronidation (4‐MUG) showed Michaelis‐Menten kinetics with aKmvalue of 6.7 µM. The inhibitory effects of the following seven NSAIDs were investigated: acetaminophen, diclofenac, diflunisal, indomethacin, ketoprofen, naproxen and niflumic acid. Niflumic acid had the most potent inhibitory effect on 4‐MUG with an IC50value of 0.0341 µM. The IC50values of diflunisal, diclofenac and indomethacin were 1.31, 24.2, and 34.1 µM, respectively, while acetaminophen, ketoprofen and naproxen showed less potent inhibition. Niflumic acid, diflunisal, diclofenac and indomethacin inhibited 4‐MUG competitively withKivalues of 0.0275, 0.710, 53.3 and 69.9 µM, respectively, being similar to each IC50value. In conclusion, of the seven NSAIDs investigated, niflumic acid was the most potent inhibitor of recombinant UGT1A9 via 4‐MUG in a competitive manner. Copyright © 2005 John Wiley & Sons, Ltd.
The effect of increased lipoprotein levels on the pharmacokinetics of cyclosporine A in the laboratory rat
Authors: Brocks Dion R. , Ala Shahram , Aliabadi Hamidreza Montazeri 
Published: November 2005

AbstractThe response of cyclosporine A (CyA) blood concentrations following changes in lipoprotein levels have been inconsistent. Some studies show increases in concentrations, whereas others have shown decreases. The intent of this study was to examine the effect of two rat models of increased lipoprotein on the pharmacokinetics of CyA. One was a simulated high fat content meal, in which 1% cholesterol in peanut oil was administered. The other was the poloxamer 407‐induced model of hyperlipidemia. Rats in these two groups were compared to a group fasted overnight before the study. In rats given a simulated high fat meal, at most time points the mean blood and plasma concentrations were lower, though not significantly, compared to fasted animals. Oral lipid led to no significant changes in the measured pharmacokinetic parameters of blood or plasma area under the concentration vs time curve (AUC), clearance (CL), volume of distribution (Vd) or plasma unbound fraction. In the poloxamer 407‐treated hyperlipidemic rats there were significant reductions in plasma unbound fraction plasma,Vdand terminal half‐life, but notAUCorCL, compared to normolipidemic rats. In contrast, theCL,Vdandt1/2in the oral lipid‐fed rats were all significantly higher than the poloxamer 407 treated animals. Oral absolute bioavailability of CyA was unchanged by oral lipid. In humans and rats the pharmacokinetics of CyA in the face of increased lipoprotein levels do not correspond well to what is typically seen for other drugs that are known to bind to lipoproteins. Copyright © 2005 John Wiley & Sons, Ltd.
Intestinal absorption characteristics of ketoprofen in rats
Authors: Choi Jun‐Shik , Jin Ming Ji , Han Hyo‐Kyung 
Published: November 2005

AbstractThe present study aims to investigate the intestinal absorption characteristics of ketoprofen in rats. The pharmacokinetic profile of ketoprofen was evaluated following a single p.o. administration of ketoprofen (1 mg/kg) to rats in the absence and presence of benzoic acid or lactic acid (2 and 10 mg/kg), the substrates of monocarboxylic acid transporters. The pharmacokinetic profiles of ketoprofen (1 mg/kg) were significantly altered by the concurrent use of benzoic acid or lactic acid (10 mg/kg), compared with the control (given ketoprofen alone). TheCmaxandAUCof ketoprofen in the presence of benzoic acid or lactic acid (10 mg/kg) were significantly (p<0.05) lower than those from the control group, while there was no significant change inTmaxand the terminal plasma half‐life (T1/2) of ketoprofen. These results suggest that ketoprofen shares a common transport pathway with benzoic acid and lactic acid during the intestinal absorption in rats. Copyright © 2005 John Wiley & Sons, Ltd.
Conformation of alloHyp in the Y position in the host–guest peptide with the pro–pro–gly sequence: Implication of the destabilization of (Pro–alloHyp–Gly)10
Authors: Jiravanichanun Nattha , Nishino Norikazu , Okuyama Kenji 
Published: November 2005

AbstractThe crystal structure of the host–guest peptide, (Pro–Pro–Gly)4–(Pro–alloHyp–Gly)–(Pro–Pro–Gly)4, was analyzed at high resolution. allohydroxyproline (alloHyp), 4S‐hydroxyproline, was successfully characterized through the use of a host–guest peptide, while the previous study indicated the inability of a triple helical formation of (Pro–alloHyp–Gly)10. A detailed analysis of alloHyp conformation in collagen‐like models sheds light on the role played by its puckering in the triple‐helix stabilization and destabilization. That is, the alloHyp typically adopts down puckering. However, it adopted up puckering in the Y position in the Pro–alloHyp–Gly guest triplet, which was not preferable conformation for alloHyp. Therefore, the energetically unfavorable conformations seemed to play the key role in giving destabilization to the triple helix in (Pro–alloHyp–Gly)10. The intrinsic hydration pattern in (Pro–Pro–Gly)9 was conserved even in the surrounding alloHyp residues. © 2005 Wiley Periodicals, Inc. Biopolymers 81: 225–233, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com