bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intelligent control of a pH process
Authors: Mészáros Alois , Čirka L’uboš , Šperka L’ubomír 
Published: February 2009

AbstractA new strategy, to augment the pH process control is offered in this paper. The intelligent controller proposed herein is based on an inverse neural plant model. An integration term is introduced to improve the pure inverse neural controller performance. This element, adjusted by a fuzzy system with respect to the control error, operates in parallel with the neural controller to ensure offset-free performance, in case of system uncertainties or modelling mismatch. Four fuzzy rules were applied to generate the integrator parameters. Experimental results, carried out under pH control on a laboratory scale set-up, demonstrate the feasibility of the proposed control system.
Magnetohydrodynamic free convection and mass transfer flow past a vertical porous flat plate with Dufour and Soret effects
Authors: Maleque Md Abdul , Alam Md Shariful 
Published: February 2009

An analysis of free convection and mass transfer unsteady magnetohydrodynamic flow of an electrically conducting viscous incompressible fluid past an infinite vertical porous plate is presented by taking into account the Dufour and Soret effects. With a goal to attain similarity solutions of the problem posed, similarity equations are derived by introducing a time dependent length scale. The non-linear similarity equations, which are locally similar, are solved numerically using shooting method. Dimensionless velocity, temperature and concentration profiles are displayed graphically for different values of the parameters entering into the problem. Finally, the corresponding local skin-friction, local Nusselt number and local Sherwood number, which are of physical interest are tabulated. Keywords: Magnetodydrodynamic, Free convection, Mass transfer, Dufour and Soret effects. Â doi: 10.3329/jname.v1i1.2035 Journal of Naval Architecture and Marine Engineering 1(2004) 18-25
Wikipediaand the Epistemology of Testimony
Authors: Tollefsen Deborah Perron 
Published: February 2009

ABSTRACTIn “Group Testimony” (2007) I argued that the testimony of a group cannot be understood (or at least cannot always be understood) in a summative fashion; as the testimony of some or all of the group members. In some cases, it is the groupitselfthat testifies. I also argued that one could extend standard reductionist accounts of the justification of testimonial belief to the case of testimonial belief formed on the basis of group testimony. In this paper, I explore the issue of group testimony in greater detail by focusing on one putative source of testimony, that ofWikipedia. My aim is to the answer the following questions: IsWikipediaa source of testimony? And if so, what is the nature of that source? Are we to understandWikipediaentries as a collection of testimonial statements made by individuals, some subset of individuals, or isWikipediaitself (the organization or theWikipediacommunity) the entity that testifies? IfWikipediaitself is a source of testimony, what resources do we have for assessing the trustworthiness of such an unusual epistemic source? In answering these questions I hope to further elucidate the nature of collective epistemic agency (Tollefsen 2006), of which group testimony is a paradigm example.When a mans Discourse begineth…at some saying of another, of whose ability to know the truth, and of whose honesty in not deceiving, he doubteth not; and then the Discourse is not so much concerning the Thing, as the Person; and the Resolution is called Beleefe, and Faith: Faith in the man. (1651/1991, Ch. 7; p. 48)
The Fate of Expertise after Wikipedia
Authors: Sanger Lawrence M. 
Published: February 2009

ABSTRACTWikipedia has challenged traditional notions about the roles of experts in the Internet Age. Section 1 sets up a paradox. Wikipedia is a striking popular success, and yet its success can be attributed to the fact that it is wide open and bottom-up. How can such a successful knowledge project disdain expertise? Section 2 discusses the thesis that if Wikipedia could be shown by an excellent survey of experts to be fantastically reliable, then experts would not need to be granted positions of special authority. But, among other problems, this thesis is self-stultifying. Section 3 explores a couple ways in which egalitarian online communities might challenge the occupational roles or the epistemic leadership roles of experts. There is little support for the notion that the distinctive occupations that require expertise are being undermined. It is also implausible that Wikipedia and its like might take over the epistemic leadership roles of experts. Section 4 argues that a main reason that Wikipedia’s articles are as good as they are is that they are edited by knowledgeable people to whom deference is paid, although voluntarily. But some Wikipedia articles suffer because so many aggressive people drive off people more knowledgeable than they are; so there is no reason to think that Wikipedia’s articles will continually improve. Moreover, Wikipedia’s commitment to anonymity further drives off good contributors. Generally, some decisionmaking role for experts is not just consistent with online knowledge communities being open and bottom-up, it is recommended as well.
Effects of ethnicity and socioeconomic status on body composition in an admixed, multiethnic population in Hawaii
Authors: Brown Daniel E. , Hampson Sarah E. , Dubanoski Joan P. , Murai Amy Stone , Hillier Teresa A. 
Published: February 2009

AbstractThis study determined ethnic differences in anthropometric measures of a sample of adults in Hawaii, examining the effects of differing degrees of ethnic admixing and socioeconomic status (SES) on the measures. Adults who had attended elementary school in Hawaii underwent anthropometric measurements and answered questionnaires about their educational attainment, income, age, cultural identity, ethnic ancestry, and health. Individuals reporting Asian American cultural identity had significantly lower mean body mass index (BMI) and waist circumference (WC) than others, whereas those with Hawaiian/Pacific Islander cultural identity had significantly higher BMI and WC. Educational attainment, but not reported family income and age, was significantly related to BMI and WC, and differences in educational attainment accounted for the increased mean BMI and WC in Hawaiian/Pacific Islanders, but did not account for the lower mean BMI and WC among Asian Americans. Higher percentage of Asian ancestry was significantly correlated with lower BMI and WC, whereas higher percentage of Hawaiian/Pacific Islander ancestry was significantly correlated with increased BMI and WC. Differences in education accounted for the significantly increased BMI in participants with a higher percentage of Hawaiian/Pacific Islander ancestry, but did not entirely account for the lower BMI in individuals with a higher percentage of Asian American ancestry. These results suggest that the high rate of obesity and its sequelae seen in Pacific Islanders may be more a result of socioeconomic status and lifestyle than of genetic propensity, whereas the lower rates of obesity observed in Asian American populations are less directly influenced by socioeconomic factors. Am. J. Hum. Biol., 2009. © 2009 Wiley‐Liss, Inc.
Design of Peptidic Foldamer Helices: A Stereochemical Patterning Approach
Authors: Mándity István M. , Wéber Edit , Martinek Tamás A. , Olajos Gábor , Tóth Gábor K. , Vass Elemér , Fülöp Ferenc 
Published: February 2009

AbstractKlares Konstruktionsprinzip: Die programmierten Sequenzen von stereochemischen Bausteinen führen zu neuartigen biomimetischen Helices. Dieser rationale Ansatz eröffnet neue Möglichkeiten beim Aufbau periodischer Sekundärstrukturen.magnified image
Phosphine‐Catalyzed Enantioselective Synthesis of Oxygen Heterocycles
Authors: Chung Ying Kit , Fu Gregory C. 
Published: February 2009

AbstractDas chirale Phosphepin 1 katalysiert die enantioselektive Umwandlung zahlreicher Hydroxy‐2‐alkinoate in gesättigte Sauerstoffheterocyclen. Auch phenolische Substrate gehen diese phosphankatalysierten Cyclisierungen ein. Die Methode eröffnet einen neuen enantioselektiven Zugang zu Tetrahydrofuranen, Tetrahydropyranen und Dihydrobenzopyranen.magnified image
Ring‐Opening Polymerization of Cyclic Esters by an Enantiopure Heteroscorpionate Rare Earth Initiator
Authors: Otero Antonio , Fernández‐Baeza Juan , Lara‐Sánchez Agustín , Alonso‐Moreno Carlos , Márquez‐Segovia Isabel , Sánchez‐Barba Luis F. , Rodríguez Ana M. 
Published: February 2009

AbstractMit erhobenem Stachel: Ein enantiomerenreiner Neodymkomplex (siehe Schema) wirkt als effizienter Initiator für eine kontrollierte Ringöffnungspolymerisation von rac‐Lactid zu einem isotaktischen Polyester. Der Heteroskorpionatkomplex wurde spektroskopisch und durch eine Röntgenstrukturanalyse charakterisiert.magnified image
Nickel‐Catalyzed Borylative Coupling of Alkynes, Enones, and Bis(pinacolato)diboron as a Route to Substituted Alkenyl Boronates
Authors: Mannathan Subramaniyan , Jeganmohan Masilamani , Cheng Chien‐Hong 
Published: February 2009

AbstractThree‐component coupling reactions of an alkyne, an enone, and a diboron reagent provide access to highly substituted alkenyl boronates in good to excellent yields (see scheme). The coupling is highly regio‐ and stereoselective, and the products are amenable to further functional‐group transformations. R1,R2=H, alkyl, aryl, CO2Me; R3=alkyl, Ph; R4,R5=H, alkyl.magnified image
Phosphine‐Catalyzed Enantioselective Synthesis of Oxygen Heterocycles
Authors: Chung Ying Kit , Fu Gregory C. 
Published: February 2009

AbstractChiral phosphepine 1 catalyzes the transformation of an array of hydroxy‐2‐alkynoates into saturated oxygen heterocycles with good enantioselectivity. Phenols are also shown to participate in such phosphine‐catalyzed cyclizations, including an asymmetric variant. This method provides a new approach to the enantioselective synthesis of tetrahydrofurans, tetrahydropyrans, and dihydrobenzopyrans.magnified image
Highly Efficient and Regioselective Platinum(II)‐Catalyzed Tandem Synthesis of Multiply Substituted Indolines and Tetrahydroquinolines
Authors: Liu Xin‐Yuan , Che Chi‐Ming 
Published: February 2009

AbstractA special advantage: The platinum(II)‐catalyzed tandem cyclization of aminoalkynes with 1,3‐diketones offers a new and highly efficient method for the synthesis of indolines and tetrahydroquinolines (see scheme; M.S.=molecular sieves). This transformation affords good to excellent product yields with high regio‐ and chemoselectivity under mild reaction conditions.magnified image
Two‐phase bifurcated dividing pipe flow
Authors: Murphy A. , Spedding P. L. , Doherty A. P. 
Published: February 2009

AbstractData are reported on the pressure drop of co‐current air–water two‐phase flow through 0.0454 m i.d. bifurcations with included angles of 60°, 90°, 120° and 180°. The pressure changes on account of the angles at the junctions depended on the superficial phase velocities and the angle of bifurcation.For the 60° lowest angle of bifurcation the pressure drop was insensitive to flow rates if the superficial liquid velocity was in the lower range at and below 0.1 m s−1. For higher liquid flows the pressure loss increased dramatically, particularly in the annular‐type regimes.When the angle at the junction was increased, negative values of pressure loss, i.e. an increase in pressure was recorded across the bifurcation in the gas velocity region under 10 m s−1and liquid rates at and above 0.1 m s−1in the slug and blow‐through slug regimes. The effect coincided with liquid separation from the inner inlet pipe wall of the junction and its subsequent reformation on the downstream walls. A second less dramatic increase in junction pressure drop occurred at the lowest liquid flow rate of 0.05 m s−1for the tee (180° bifurcation) that was due both to the smooth transition of liquid through the junction and the damping of surface waves in stratified‐type flow.A flow regime map was presented for the tee junction. The inlet flow showed agreement with the map but the flow regimes found in the outlet arms of the junction tended to form earlier than expected being triggered by the pressure disturbances in the passage through the bifurcation. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Determining the optical and geometrical properties of irregular fibers during the dynamic cold drawing process
Authors: Hamza A. A. , Sokkar T. Z. N. , El‐Bakary M. A. , El‐Morsy M. A. , Ali A. M. 
Published: February 2009

AbstractA dynamic method was suggested to determine the variation of both refractive index and transverse sectional area of regular and/or irregular fibers during the dynamic cold drawing process. The suggested method depends on the physical principle of constant volume of the filament during the cold drawing process. The mathematical analysis of the method was given. The optical and geometrical properties of acrylic fibers with denier 2 and polypropylene fibers were determined. One dimension optical Fourier transform was used for automatic analysis of microinterferograms. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effect of rubber content on mechanical properties and heat shrinkage of ethylene vinyl acetate copolymer blended with epoxidized natural rubber
Authors: Tanrattanakul Varaporn , Kaewprakob Thongsak 
Published: February 2009

AbstractEthylene vinyl acetate (EVA, 18 mol % vinyl acetate) and epoxidized natural rubber (ENR, 50 mol % epoxidation) were blended in an internal mixer and compared to EVA. Dicumyl peroxide (DCP) was used as a curing agent. The blends consisted of 10–50 wt % of ENR and were compared with crosslinked EVA in terms of heat shrinkage, mechanical properties, and degree of crystallinity. It is found that the blends showed a decrease in mechanical properties with increasing ENR content because DCP was not a good vulcanizing agent of ENR. The addition of ENR did not affect heat shrinkability of EVA. The maximum heat shrinkage obtained was 80% for EVA and the blends. ENR did not affect thermal properties of EVA investigated by the differential scanning calorimetry. The X‐ray diffractometry showed discrepancy in degree of crystallinity before and after specimen stretching and after heat shrinking. It is believed that ENR particles decreased molecular orientation of EVA resulting in a decrease in degree of crystallinity but the remained orientation was sufficient for heat shrinking. The blend showed better extrudability than EVA after increasing take‐up speed. Therefore, the extruded tube prepared from the blend provided higher heat shrinkage than EVA tube. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and Cytotoxicity Screening of Piperazine‐1‐carbodithioate Derivatives of 2‐Substituted Quinazolin‐4(3H)‐ones
Authors: Cao Sheng‐Li , Guo Yan‐Wen , Wang Xian‐Bo , Zhang Mei , Feng Yu‐Ping , Jiang Yu‐Yang , Wang Yue , Gao Qian , Ren Jian 
Published: February 2009

AbstractA new series of piperazine‐1‐carbodithioate derivatives of 2‐substituted quinazolin‐4(3H)‐ones were synthesized via a five‐steps procedure starting from 2‐amino‐5‐methylbenzoic acid. The cytotoxicity of the resulting compounds against A‐549 (human lung cancer), HCT‐8 (human colon cancer), HepG2 (human liver cancer), and K562 (human myelogenous leukaemia) cell lines was determined by the MTT assay. Preliminary screening results of these compounds are reported.
Conformational evaluation of labeled C3′‐O‐P‐13CH2‐O‐C4″ phosphonate internucleotide linkage, a phosphodiester isostere
Authors: Točík Zdeněk , Buděšínský Miloš , Barvík Ivan , Rosenberg Ivan 
Published: February 2009

AbstractModified internucleotide linkage featuring the C3′‐O‐P‐CH2‐O‐C4″ phosphonate grouping as an isosteric alternative to the phosphodiester C3′‐O‐P‐O‐CH2‐C4″ bond was studied in order to learn more on its stereochemical arrangement, which we showed earlier to be of prime importance for the properties of the respective oligonucleotide analogues. Two approaches were pursued: First, the attempt to prepare the model dinucleoside phosphonate with 13C‐labeled CH2 group present in the modified internucleotide linkage that would allow for a more detailed evaluation of the linkage conformation by NMR spectroscopy. Second, the use of ab initio calculations along with molecular dynamics (MD) simulations in order to observe the most populated conformations and specify main structural elements governing the conformational preferences. To deal with the former aim, a novel synthesis of key labeled reagent (CH3O)2P(O)13CH2OH for dimer preparation had to be elaborated using aqueous 13C‐formaldehyde. The results from both approaches were compared and found consistent. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 514–529, 2009.This 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
Replacement of the 4′‐Hydroxy Group of Amodiaquine and Amopyroquine by Aromatic and Aliphatic Substituents: Synthesis and Antimalarial Activity
Authors: Păunescu Emilia , Susplugas Sophie , Boll Emmanuelle , Varga Richard , Mouray Elisabeth , Grosu Ion , Grellier Philippe , Melnyk Patricia 
Published: February 2009

Abstract4′‐Substituted analoguesof amodiaquine and amopyroquine were synthesized using Csp2–Csp2and Csp2–Csp3Suzuki–Miyaura cross‐coupling reactions as the key step. The new derivatives were found to be active against both chloroquine (CQ)‐sensitive and CQ‐resistant strains ofP. falciparum, with IC50values in the range of 7–200 nM; one compound showed in vivo activity.magnified imageThe prophylactic administration of amodiaquine (AQ), a 4‐aminoquinoline antimalarial drug, has been associated with side effects such as agranulocytosis and liver damage. The toxicity of this drug is mediated by amodiaquine quinone‐imine, an electrophilic metabolite. Replacement of the 4′‐hydroxy function of AQ with various alkyl, aryl, or heteroaryl substituents would provide analogues that avoid metabolism to potentially toxic derivatives. Following a multistep procedure, 33 compounds containing hydrophobic groups at the 4′‐position were synthesized using Csp2–Csp2and Csp2–Csp3Suzuki–Miyaura cross‐coupling reactions as the key step. The new derivatives were found to be active against both chloroquine (CQ)‐sensitive and CQ‐resistant strains ofP. falciparum, with IC50values in the range of 7–200 nM. Alkyl analogues are more efficient than aryl or heteroaryl derivatives. All compounds were also assessed for their cytotoxicity and ability to inhibit β‐hematin formation in vitro. A detailed investigation of the structure–activity relationships for these new compounds was carried out; the 4′‐methyl compound showed interesting in vivo antimalarial activity.
Dimensions of coupling in middleware
Authors: Aldred Lachlan , van der Aalst Wil M. P. , Dumas Marlon , ter Hofstede Arthur H. M. 
Published: February 2009

AbstractIt is well accepted that different types of distributed architectures require different degrees of coupling. For example, in client‐server and three‐tier architectures, application components are generally tightly coupled, both with one another and with the underlying middleware. Meanwhile, in off‐line transaction processing, grid computing and mobile applications, the degree of coupling between application components and with the underlying middleware needs to be minimized. Terms such as ‘synchronous’, ‘asynchronous’, ‘blocking’, ‘non‐blocking’, ‘directed’, and ‘non‐directed’ are often used to refer to the degree of coupling required by an architecture or provided by a middleware. However, these terms are used with various connotations. Although various informal definitions have been provided, there is a lack of an overarching formal framework to unambiguously communicate architectural requirements with respect to (de‐)coupling. This article addresses this gap by: (i) formally defining three dimensions of (de‐)coupling; (ii) relating these dimensions to existing middleware; and (iii) proposing notational elements to represent various coupling integration patterns. This article also discusses a prototype that demonstrates the feasibility of its implementation. Copyright © 2009 John Wiley & Sons, Ltd.
Low‐Valent Indium as a Catalyst for the Allylation of Ketones and N‐Acylhydrazones
Authors: Yoo Woo‐Jin , Li Chao‐Jun 
Published: February 2009

AbstractIndium summer: The use of low‐valent indium species in organic chemistry was, until quite recently, underdeveloped. Then came reports of indium(I) halides serving as excellent catalysts for the allylation of ketones and N‐acylhydrazones with pinacol allylboronates, and more recently of indium(0) being used as a catalyst for the allylation of ketones in water.magnified image
Synthesis, Characterisation, Electrochemistry and Ion‐Binding Studies of Ruthenium(II) and Rhenium(I) Bipyridine/Crown Ether Receptor Molecules
Authors: Boricha Vinod P. , Patra Subrata , Chouhan Yogendra S. , Sanavada Pankaj , Suresh E. , Paul Parimal 
Published: February 2009

AbstractA number of molecular receptors containing a ruthenium(II)/rhenium(I) bipyridine moiety as fluorophore and a crown ether, connected to the 4,4′‐positions of the bipyridine/phenanthroline unit through >C=O and ‐HC=N‐ spacers, as ionophore have been synthesised and characterised. The luminescence and electrochemical properties of these receptors have been studied. The cation‐binding properties of these molecules have been investigated with the cations Na+, K+, Rb+, Mg2+, Ca2+, Zn2+, Cd2+, Hg2+, Pb2+ and Cu2+ and the recognition event monitored by 1H NMR spectroscopy, luminescence, the oxidation potential of the metal ion and UV/Vis absorption studies. The emission intensities of complexes 1–3 are strongly quenched by the addition of Pb2+, Cu2+, Hg2+ and Na+, whereas a significant enhancement of the emission intensities is observed for 4 in the presence of Cu2+ and Hg2+ and for 5 in the presence of Cd2+ and Hg2+. Luminescence titrations for 1–5 with the above‐mentioned metal ions have been carried out. The binding constants (Ks) and stoichiometry of the complexes have been calculated from titration data, with values of Ks ranging from 9.97 × 103 to 1.28 × 102 M–1 in the decreasing order Pb2+ > Na+ > Cu2+ > Hg2+ > Cd2+. The stoichiometries found for 1–3 and 5 are in the range 1.85–2.09 and for 4 0.99–1.04. A 1H NMR spectroscopic study with selected metal ions exhibits significant spectral changes for the protons attached to the crown moiety; a few significant changes are also noted in the aromatic region. Among the ions studied, the highest change is observed with Na+ and Pb2+, whereas K+ does not show any significant change. The electrochemical study exhibits a significant cathodic shift of the oxidation potentials of the RuII centre in the presence of Na+ and Pb2+, thereby indicating complexation of these ions with the crown moiety. The electronic spectra, however, do not show significant spectral changes with various metal ions except for that of the ReI complex 6, which exhibits some change upon addition of Na+. The results obtained are presented and discussed in light of selectivity and intramolecular energy‐transfer.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)