bluuebunny/crossref_metadata_2025_split huggingface dataset:
Establishment of an immortalized PARP‐1−/− murine endothelial cell line: A new tool to study PARP‐1 mediated endothelial cell dysfunction
Authors: Carrillo Ana , Monreal Yolanda , Ramirez Pablo , Suarez Eduardo , Parrilla Pascual , Menissier‐de Murcia Josiane , de Murcia Gilbert , Alvarez‐Vallina Luis , Yélamos José 
Published: February 2005

AbstractPoly(ADP‐ribose) polymerase‐1 (PARP‐1) plays a critical role in endothelial cell dysfunction associated with various pathophysiological conditions. To elucidate PARP‐1 pathways involved in endothelial cell dysfunction, it is essential to establish “in vitro” experimental models using isolated endothelial cells. So far, two approaches have been used: primary endothelial cells from PARP‐1−/− mice which have a limited life‐span, being a major handicap if large quantities of cells are required; and pharmacological inhibition of PARP in PARP‐1+/+ endothelial cell lines, which is not specific for PARP‐1 and would have biological effects different that genetic inhibition. To overcome these limitations, we have established an immortalized PARP‐1−/− endothelial cell line (HYKO6) by transfection of primary cells with a plasmid containing the SV40 genome and selected on the basis of morphological and phenotypical features. The HYKO6 cell line exhibited endothelial characteristics, such as constitutive expression of CD105, CD31, ICAM‐2, VCAM‐1, and von Willebrand factor and formation of capillary‐like structures (CLS) on Matrigel surface. However, expression of ICAM‐1 antigen is lost in the HYKO6 cells. After TNF‐α treatment, HYKO6 cells exhibited increased expression of E‐selectin and VCAM‐1. Likewise, NF‐κB‐dependent transcriptional activation was increased in the HYKO6 cell line in response to TNF‐α at a level similar to that found for primary PARP‐1−/− cells. This cell line should provide, for the first time, a valuable tool to study PARP‐1 pathways in endothelial cell dysfunction. © 2005 Wiley‐Liss, Inc.
mRNA expression of AMPA receptors and AMPA receptor binding proteins in the cerebral cortex of elderly schizophrenics
Authors: Dracheva Stella , McGurk Susan R. , Haroutunian Vahram 
Published: February 2005

AbstractL‐α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionic acid (AMPA) receptors (AMPARs) mediate the majority of the fast excitatory transmission in the CNS. To determine whether gene expression of AMPARs and/or AMPAR binding proteins, which control response/sensitivity of AMPAR‐bearing neurons to glutamate, are altered in schizophrenia, mRNA expression and abundance of AMPAR subunits (GluR1–4) and several AMPAR binding proteins (SAP97, PICK1, GRIP, ABP) were measured in the dorsolateral prefrontal cortex (DLPFC) and the occipital cortex of elderly schizophrenia patients (n = 36) and matched normal controls (n = 26) by quantitative real‐time PCR. The mRNA expression of GluR1, GluR4, and GRIP in the DLPFC and expression of the GluR4, GRIP, and ABP in the occipital cortex were significantly elevated in schizophrenics. GluR1 and ABP mRNA expression in the occipital cortex and GluR2, GluR3, SAP97, and PICK1 expression in either cortical area were not significantly altered. The data also demonstrated significant differences in the abundances of mRNAs encoding GluR1–4 subunits (GluR2 > GluR3 > GluR1 > GluR4) and of AMPAR binding proteins (SAP97 > PICK1 > GRIP > ABP) in both diagnostic groups. GluR2 (58–64%) and GluR3 (24–29%) were the major components of the AMPAR mRNA in both cortical areas, implying that the major AMPAR complexes in the human cortex are probably those containing GluR2 and GluR3 subunits. Small but significant differences in the amounts of GluR2, GluR3, and GRIP mRNAs were detected between the two cortical areas: more GluR3 and GRIP but less GluR2 were detected in the DLPFC than in the occipital cortex. © 2005 Wiley‐Liss, Inc.
2‐Naphthol‐containing β‐cyclodextrin–epichlorohydrin copolymers: synthesis, characterization and fluorescence studies
Authors: Zohrehvand Shiva , Evans Christopher H 
Published: February 2005

AbstractFluorescent 2‐naphthol (NOH)‐containing β‐cyclodextrin (β‐CD)–epichlorohydrin (EP) copolymers were synthesized. Polymerization was confirmed through viscosity and FT‐IR spectroscopic measurements. Under certain conditions, the copolymers were water‐soluble (molar ratio of EP/β‐CD <22:1), while under other conditions water‐insoluble gels were formed (EP/β‐CD ≥ 22:1). Increase of the EP content to EP/β‐CD ≤ 39:1 increased the fluorescence intensity of the copolymer and shifted the emission maximum from 422 nm toward 352 nm (measured at pH ≥ 12). Further increases in the EP content resulted in a slight decrease in the fluorescence intensity. The fluorescence properties of our system at EP/β‐CD < 22 were sensitive to pH variation, while at EP/β‐CD ≥ 22 no pH effect was observed. These variations can be explained in terms of the exposure of the fluorophore to solvent in soluble versus insoluble polymers, as well as changes in the mode of association (host–guest complexation, trapping within the polymer network, covalent bonding, etc) of NOH with the polymers. Crystallographic studies on a single crystal grown in the absence of EP, but under basic conditions, suggest that host–guest complexation is not an important mode for NOH incorporation. Copyright © 2005 Society of Chemical Industry
Fast crystallization of poly(3‐hydroxybutyrate) and poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) with talc and boron nitride as nucleating agents
Authors: Kai Weihua , He Yong , Inoue Yoshio 
Published: February 2005

AbstractThe crystallization behavior of poly(3‐hydroxybutyrate) (PHB) and poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) induced by two kinds of nucleating agents, boron nitride (BN) and talc, was investigated by differential scanning calorimetry, polarized optical microscopy and X‐ray diffraction. Both BN and talc have good nucleating ability in the crystallization of PHB and PHBV. From these results, combined with molecular weight measurement by gel permeation chromatography, the mechanism of nucleation by BN and talc in the crystallization of PHB and PHBV has been proposed. BN acts as a nucleating agent itself and initiates nucleation in the crystallization of PHB and PHBV. Talc acts in a different way. It reacts as a chemical reagent with the molten chains of PHB/PHBV, while the reaction product acts as the true nucleating agent, which lowers the crystallization barriers of PHB and PHBV. 1H NMR spectroscopy provides evidence for the reaction between PHB and talc and supports the proposed nucleation mechanism. Copyright © 2005 Society of Chemical Industry
Immobilization and activation of vanadium(III) and titanium(III) single‐site catalysts for ethylene polymerization using MgCl2‐based supports
Authors: Severn John R , Duchateau Robbert , Chadwick John C 
Published: February 2005

AbstractSignificant increases in the activity of vanadium(III) amidinate catalysts for ethylene polymerization have been obtained by immobilization on a MgCl2‐based support prepared by reaction of AlEt3 with a MgCl2/ethanol adduct. Catalyst immobilization and activation on this type of support prevents the rapid decay in activity observed under homogeneous polymerization conditions with unsupported catalysts. Stable polymerization activity is also observed with analogous titanium(III) complexes. Polyethylene with narrow molecular weight distribution and spherical particle morphology is obtained without reactor fouling. Copyright © 2005 Society of Chemical Industry
Synthesis and monomer reactivity ratio of cobalt‐containing hybrid polysilanes
Authors: Si Tae Sung , Koo Sang Man 
Published: February 2005

AbstractDichloromethylsilylcobaltcarbonyl (DCMSC) was synthesized by the reaction of dichloromethylsilane (DCMS) with dicobaltoctacarbonyl (DCOC) and used to prepare metal‐containing polysilanes. Copolymers of DCMSC with dichlorodimethyl‐ (DCDMS), dichlorodiethyl‐ (DCDES), dichloromethylphenyl‐ (DCMPS) silane were obtained using reductive coupling polymerization. The molecular weight of the copolymers increased regularly in the initial stage of the reaction but approached equilibrium values as the reaction proceeded. Depending on the monomer reactivity ratios, copolymers 2, 3 and 4 could have either alternating or block‐like copolymer structures. Increasing amounts of carbons in the side‐chain of the copolymers leads to block‐like composition. Copyright © 2005 Society of Chemical Industry
Molecular orientation behavior of poly(vinyl chloride) as influenced by the nanoparticles and plasticizer during uniaxial film stretching in the rubbery stage
Authors: Yalcin Baris , Cakmak Miko 
Published: February 2005

AbstractThe structural evolution during uniaxial stretching of poly(vinyl chloride) films was studied using our real time spectral birefringence stretching machine. The effect of clay loading and the amount of plasticizer as well as the rate effects on the birefringence development and true mechanical response are presented with a final model summarizing the molecular phenomena during stretching. Mechano‐optical studies revealed that birefringence correlated with mechanical response (stress, strain, work) nonlinearly. This was primarily attributed to the preexisting strong network of largely amorphous chains connected via small crystallites that act as physical crosslinking points. These crystallites are not easily destroyed during the high‐speed stretching process as evidenced from the birefringence–true strain curves along with the X‐ray crystallinity measurements. At high speeds, the amorphous chains do not have enough time to relax and hence attain higher orientation levels. The crystallites, however, orient more efficiently when stretched at slow speeds. Apparently, some relaxation of the surrounding amorphous chains helps rotate the crystallites in the stretching direction. Overall birefringence is higher at high stretching speeds for a given true strain value. When the nanoparticles are incorporated, the orientation levels are increased significantly for both the crystalline and amorphous phases. Nanoplatelets increase the continuity of the network because they have strong interaction with the amorphous chains and/or crystallites. This in turn helps transfer the local stresses to the attached chains and increase the orientation levels of the chains. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 724–742, 2005
Prediction of protein relative solvent accessibility with a two‐stage SVM approach
Authors: Nguyen Minh N. , Rajapakse Jagath C. 
Published: February 2005

AbstractInformation on relative solvent accessibility (RSA) of amino acid residues in proteins provides valuable clues to the prediction of protein structure and function. A two‐stage approach with support vector machines (SVMs) is proposed, where an SVM predictor is introduced to the output of the single‐stage SVM approach to take into account the contextual relationships among solvent accessibilities for the prediction. By using the position‐specific scoring matrices (PSSMs) generated by PSI‐BLAST, the two‐stage SVM approach achieves accuracies up to 90.4% and 90.2% on the Manesh data set of 215 protein structures and the RS126 data set of 126 nonhomologous globular proteins, respectively, which are better than the highest published scores on both data sets to date. A Web server for protein RSA prediction using a two‐stage SVM method has been developed and is available (http://birc.ntu.edu.sg/∼pas0186457/rsa.html). Proteins 2005. © 2005 Wiley‐Liss, Inc.
Nonadiabatic evolution of electronic states by electron nuclear dynamics theory
Authors: Hagelberg Frank 
Published: February 2005

AbstractThe problem of how to determine the nonadiabatic content of any given dynamic process involving molecular motion is addressed in the context of Electron Nuclear Dynamics (END) theory. Specifically, it is proposed to cast the dynamic END wave function into the language of static electronic configurations with time dependent complex‐valued amplitudes. This is achieved by adiabatic transport of an electronic basis along the classical nuclear trajectories of the studied molecular system, as yielded by END simulation. Projecting the dynamic wave function on this basis yields a natural distinction between adiabatic and nonadiabatic components of the motion considered. Tracing the evolution of the leading configurations is shown to be a helpful device for clarifying the physical nature of electronic excitation processes. For illustration of these concepts, dynamic configuration analysis is applied to the scattering of a proton by a lithium atom. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Amount of effective sound pressure among pneumatic oscillations in side channel compressors
Authors: Surek D. 
Published: February 2005

AbstractMaschinen und Anlagen, die im Nahbereich von Menschen betrieben werden, müssen der Geräuschuntersuchung und der Geräuschbegrenzung unterzogen werden. Dazu gehören auch die Ventilatoren, Pumpen und Verdichter. Es ist bekannt, dass nur ein geringer Teil der Gasdruckschwingungen, die durch die turbulente Wirbelströmung, durch Strömungsablösungen oder durch starke Expansionsströmungen entstehen, als Schalldruck abgestrahlt und in der Umgebung fortgepflanzt wird. Obwohl es mathematische Modelle über die Schallentstehung und die Schallfortleitung gibt, ist bisher der akustische Anteil einer Wirbelströmung bzw. ihrer Druckschwingung nicht bekannt geworden. Durch parallele Messungen der Gasdruckschwingung in einer Maschine und des Schalldruckes an den Schallquellen können diese Verhältniswerte in Abhängigkeit der Entfernung von der Schallquelle und von den Betriebsparametern des Verdichters ermittelt werden. Im folgenden Beitrag werden diese Werte für einen Seitenkanalverdichter ermittelt.
Application of oxygen probes by plasma nitriding
Authors: Berg Hans‐Joachim , Zimdars Heinz , Spies Heinz‐Joachim 
Published: February 2005

AbstractFür das Plasmanitrieren, ‐nitrocarburieren und –carburieren im Niederdruckbereich zwischen 10 und 300 Pa wurden gaspotenziometrische beheizbare oxidionenleitende Sauerstoffmesszellen (YSZ) in Sondenausführung technologisch erprobt, die bei Prozesstemperaturen auch unter 500 °C geeignet sind, den Sauerstoffpartialdruck bzw. den Redoxquotienten, QH= p(H2O) / p(H2) im Prozessgas exakt zu messen. Der Einsatz erfolgte in unterschiedlichen Sondenkombinationen. Methanzusätze bis 3 Vol.‐% haben beim Plasmanitrocarburieren und ‐carburieren bei der Betriebstemperatur der Sonden von 600 °C auf das Zellspannungssignal noch keinen Einfluss. Im Ergebnis zeigte sich die prinzipielle Eignung zweier Sondenkonstruktionen mit Luft‐ und festen Cu/Cu2O‐Bezugselektroden. Erstmals ist es gelungen, mit einer neu entwickelten Messtechnik die Voraussetzungen zu schaffen, um den Einfluss des Sauerstoffs bei plasmagestützten Prozessen und niedrigeren Drücken systematisch untersuchen zu können.
Plasma deposition technology for solar cell manufacturing
Authors: Roth Silvia 
Published: February 2005

AbstractDie Photovoltaik, das heißt die Gewinnung elektrischer Energie aus Licht, ist ein wichtiges Glied in der Kette der regenerativen Energien, wobei das weitere Wachstum der Photovoltaikindustrie wesentlich von der Kostenreduzierung bei der Herstellung der Solarmodule bestimmt wird. Potentiale für die Erreichung dieses Zieles liegen sowohl in kostengünstigerem Basismaterial für die Solarzellen, in der Kostenreduzierung bei der Zell‐ und Modulherstellung und in der Erhöhung der Effizienz der Solarzellen. Ein wesentlicher Prozessschritt bei der Herstellung von kristallinen Siliziumsolarzellen ist deren Beschichtung mit einer Antireflex‐ und Passivierungsschicht. Im Vakuum mittels PECVD (Plasma Enhanced Chemical Vapour Deposition) abgeschiedene, amorphe, wasserstoffreiche Siliziumnitrid‐(SiN)‐schichten eignen sich sowohl als Antireflexschicht als auch für die Oberflächen‐ und Volumenpassivierung von Silizium‐Solarzellen, die insbesondere bei multikristallinen Silizium‐Solarzellen eine signifikante Erhöhung des Wirkungsgrades bewirkt. Mit dem Anlagenkonzept “SiNA” wurde eine Serie leistungsfähiger, industrietauglicher Anlagen für die SiN‐Beschichtung entwickelt und qualifiziert, die sich neben hervorragenden Schichteigenschaften durch hohe Durchsätze, hohe Verfügbarkeit und ein wartungsfreundliches Design auszeichnen. Nachfolgend werden Leistungsparameter der Systeme und relevante Daten aus deren Einsatz unter Produktionsbedingungen vorgestellt.
Yeast populations associated with Ghanaian cocoa fermentations analysed using denaturing gradient gel electrophoresis (DGGE)
Authors: Nielsen D. S. , Hønholt S. , Tano‐Debrah K. , Jespersen L. 
Published: February 2005

AbstractThe yeast populations associated with the fermentation of Ghanaian cocoa were investigated using denaturing gradient gel electrophoresis (DGGE). Samples were collected at 12–24 h intervals from heap and tray fermentations, at three different fermentation sites and different periods during the season. Eukaryotic universal primers were used to amplify a fragment of the 26S rRNA gene. The DGGE profiles were relatively complex, underlining that the fermentation of cocoa is a complex microbial process. The identities of selected fragments in the denaturing gels were revealed by sequencing. Hanseniaspora guilliermondii, Candida krusei and Pichia membranifaciens were detected from most fermentations, indicating their possible important role in the fermentation of Ghanaian cocoa. Saccharomyces cerevisiae and Candida zemplinina were almost exclusively detected during tray fermentations. The developed DGGE protocol was compared with traditional culture‐based isolations. The results were comparable but slightly different, as one yeast species (C. zemplinina) was only detected using DGGE. On the other hand, Trichosporon asahii yielded only faint bands in the denaturing gels, despite the fact that it was detected using culture‐based methods. Analysis of pure cultures showed that the targeted region of the 26S rRNA gene was poorly amplified in T. asahii, whereas all other investigated isolates were amplified efficiently using the chosen PCR approach. Cluster analysis revealed that the DGGE profiles clustered according to fermentation method and fermentation site. Furthermore, clustering according to progress in the fermentation was observed. The DGGE technique therefore seems to offer a relatively fast and reliable method for studying yeast population dynamics during cocoa fermentations. The nucleotide sequences determined in this study have been assigned Genbank Accession Nos AY762330–AY762349. Copyright © 2005 John Wiley & Sons, Ltd.
The High‐Temperature Modification of GdNiIn2 ‐ An Intergrowth Structure of MgCuAl2‐Related Slabs
Authors: Zaremba Vasyl' I. , Hlukhyy Viktor , Pöttgen Rainer 
Published: February 2005

AbstractThe high‐temperature modification of GdNiIn2 was prepared by arc‐melting of the elements and subsequent annealing of the sample at 1270 K. Crystals of HT‐GdNiIn2 were grown with a special annealing program. HT‐GdNiIn2 was investigated by X‐ray diffraction on powders and single crystals. This indide crystallizes in a new structure type, space group Cmcm, a = 433.4(3), b = 1803(1), c = 2983(2) pm, wR2 = 0.1142, 2306 F2 values, and 90 variable parameters. All nickel atoms in the HT‐GdNiIn2 structure have a distorted trigonal prismatic coordination by gadolinium and indium atoms. From a geometrical point of view, the structure of HT‐GdNiIn2 may be described as an intergrowth of distorted LT‐GdNiIn2 slabs with MgCuAl2 structure. The Ni‐In and In‐In contacts have the shortest interatomic distances within the HT‐GdNiIn2 structure. The nickel and indium atoms form a three‐dimensional [NiIn2] polyanion in which the gadolinium atoms fill distorted pentagonal channels. An initial approximation formula may be written as Gd3+[NiIn2]3‐ therefore.
Synthese, thermochemische Eigenschaften und Kristallstruktur von Bi7Cl10
Authors: Hampel Silke , Schmidt Peer , Ruck Michael 
Published: February 2005

AbstractSchwarze Kristalle des Bismutsubchlorids Bi7Cl10 wurden durch langsame Abkühlung stöchiometrischer Gemenge von Bi und BiCl3 von 500 °C auf Raumtemperatur erhalten. Mittels thermischer Analysen wurde das Zustandsdiagramm Bi/BiCl3 präzisiert. Bi7Cl10 zersetzt sich bei 190 ± 5 °C peritektoid in Bi6Cl7 und BiCl3. Das Zustandsbarogramm des binären Systems wurde über Gesamtdruckmessungen im Membran‐Nullmanometer bestimmt. Aus den Druckfunktionen der Bismutchloride sowie aus Messungen der Molwärme von Bi6Cl7 wurden die thermodynamischen Standarddaten abgeleitet: ΔH°B(Bi6Cl7, 298) = ‐895 ± 5 kJ · mol‐1; S°(Bi6Cl7, 298) = 620 ± 10 J · mol‐1K‐1; ΔH°B(Bi7Cl10, 298) = ‐1310 ± 10 kJ · mol‐1; S°(Bi7Cl10, 298) = 730 ± 20 J · mol‐1K‐1. Unter Verwendung der Daten wurden thermodynamische Modellierungen der Festkörper‐Gasphasen‐Gleichgewichte durchgeführt, mit deren Hilfe die Synthese von Bi7Cl10 optimiert werden konnte. Die phasenreine Gasphasenabscheidung von Bi7Cl10 ist aufgrund der Kondensation der dominierenden Gasphasenspezies im Existenzbereich der Verbindung nicht möglich. Aus Röntgenbeugungsuntersuchungen an Einkristallen geht hervor, dass Bi7Cl10 bei Raumtemperatur in der tetragonalen Raumgruppe I41/a c d mit a = 28, 235(3) und c = 39, 950(4) Å kristallisiert (Z = 64). In der Kristallstruktur sind Polykationen Bi95+, welche die Gestalt dreifach überkappter trigonaler Prismen haben, in ein Chlorobismutat(III)‐Raumnetzwerk [Bi5Cl205‐] eingebettet.
Verdrängung von η6‐π‐Wechselwirkungen durch N‐Donor‐Liganden: Von ein‐dimensionalen Samarium‐ und Ytterbium‐Carbazolaten zu monomeren Einheiten mit N‐Phenylpiperazin
Authors: Quitmann Catharina C. , Müller‐Buschbaum Klaus 
Published: February 2005

AbstractKristalle von [Yb2(Cbz)4(Phpip)4]·2Phpip (1), [Sm(Cbz)3(Phpip)2]·8/3Phpip (2) und [Yb(Cbz)2(Phpip)3][Yb(Cbz)3(Phpip)2] (3) wurden aus den Konkurrenzreaktionen von [Yb2(Cbz)4] und [Sm2(Cbz)5]CbzH (Cbz = Carbazolat‐Anion, C12H8N‐) mit N‐Phenylpiperazin (Phpip = (C6H5)C4H8NNH) und Carbazol (C12H8NH) erhalten. Dabei werden die Kettenstrukturen unter Verlust der π‐Wechselwirkungen bis hin zu Monomeren mit vollständiger Stickstoff‐Koordination der Selten‐Erd‐Ionen abgebaut.
Solid‐state NMR Investigations on Si‐B‐C‐N Ceramics derived from Boron‐Modified Poly(allylmethylsilazane)
Authors: Berger Frank , Müller Anita , Aldinger Fritz , Müller Klaus 
Published: February 2005

AbstractMultinuclear (13C,29Si,11B,1H) solid‐state NMR and EPR spectroscopy are employed to study the thermolysis of boron‐modified poly(allylmethylsilazane), [B{C3H6‐Si(CH3)NH}3]n, from which a quaternary Si‐C‐B‐N ceramic is formed. The investigations are primarily focused on the characterization of the amorphous intermediates on the atomic scale, where such spectroscopic techniques have demonstrated their particular suitability. In addition, NMR data are provided for the transformation from the amorphous to the crystalline ceramic. It is shown that the transformation of the polymeric precursor into the (amorphous) pre‐ceramic network is completed at 600 °C. At this temperature BN domains as well as SiCxN4‐xunits of mixed composition are formed. Above this temperature, a continuous transformation to the final ceramic material takes place. At 1400 °C the amorphous ceramic consists of three main components: (i) amorphous (graphite‐like) carbon, (ii) BN domains (mainly hexagonal boron nitride), and (iii) a Si‐C‐N matrix (SiCxN4‐xunits with x = 0, 1, 2 or 4). The EPR measurements reveal the presence of carbon‐centred free radicals between 600 and 1400 °C, which also have some impact on the13C NMR data. The NMR investigations further demonstrate that in the temperature range between 1600 and 1800 °C a demixing of the amorphous ceramic sets in, along with the formation of crystalline silicon nitride and silicon carbide phases. Likewise, structural changes for BN domains are registered that are attributed to the formation of turbostratic B‐N‐(C) interface layers. It is interesting to note that a finite amount of hydrogen can be detected in the ceramic samples even after exposure to temperatures near 2000 °C.