bluuebunny/crossref_metadata_2025_split huggingface dataset:
Apport du paradigme de production d'informations dans l'étude des dissociations entre les mesures de mémoire
Authors: Taconnat Laurence 
Published: November 2007

Summary : Contribution of word generation paradigm to the study of dissociation between memory measures
The generation effect indicates that self-generated stimuli are recalled and recognized better than read stimuli. A positive generation effect is generally observed on generated items, but a negative generation effect can also occur, resulting in a reduction in the recall of information related to the context of encoding. These effects are proposed to be mainly due to the reinforcement ofthe semantic processing implemented at the moment of the production as well as increased of mobilization ofthe attentional resources. The negative generation effect often observed on memory source supports an item-source tradeoff hypothesis in which the encoding of an item and source information are dissociable from one another. However, the generation of information is likely to increase awareness in the recognition memory. Thus, the study of the cognitive mechanisms that underlie the generation effect could corroborate the dissociation already observed in episodic memory, but also dissociation between implicit and explicit memory.
Key words : generation effect, elaboration of processes, episodic memory, source memory, item memory, implicit memory.
The Locus of Free Charge‐Carrier Generation in Solution‐Cast Zn1–xMgxO/Poly(3‐hexylthiophene) Bilayers for Photovoltaic Applications
Authors: Piris J. , Kopidakis N. , Olson D. C. , Shaheen S. E. , Ginley D. S. , Rumbles G. 
Published: November 2007

AbstractThe photoconductivity of solution‐cast Zn1–xMgxO (x=0‐0.4) and poly(3‐hexylthiophene) (P3HT) thin films, and Zn1‐xMgxO/P3HT bilayers is investigated using Time‐Resolved Microwave Conductivity (TRMC) with the aim of determining the locus of free charge carrier generation in the bilayer system. The photoconductivity of Zn1–xMgxO thin films, under illumination with 300 nm laser pulses, is limited by the formation of stable excitons and by scattering of the carriers at grain boundaries. The electron mobility in Zn1–xMgxO films decreases exponentially with Mg concentration, up to x=0.4. In agreement with previous work, free carriers are observed in the P3HT film under illumination with 500 nm pulses in the absence of an acceptor. Under illumination with 500 nm pulses, where only the polymer absorbs, the TRMC signal for the Zn1–xMgxO/P3HT bilayers for x≥0.2 is the same as that of pure P3HT, indicating that free carrier generation in these bilayers occurs predominately by exciton dissociation in the polymer bulk, and not at the interface between the polymer and the solution‐cast oxide. At lower Mg concentrations (x<0.2) the TRMC signal increases with decreasing x following the dependence of the electron mobility in the oxide but its light intensity dependence remains consistent with free carrier generation in the polymer bulk. To explain these results and previously published photovoltaic device data (Adv. Funct. Mater. 2007, 17, 264) we propose that free carrier generation in the bilayers predominantly occurs in the bulk of P3HT, and is followed by electron injection to the oxide to yield photocurrent in photovoltaic cells. The dependence of the TRMC signal of the bilayers on Mg concentration is explained in terms of the yield for free carrier generation in the polymer and the relative contributions of electrons in the oxide and holes in the polymer.
A New Donor–Acceptor–Donor Polyfluorene Copolymer with Balanced Electron and Hole Mobility
Authors: Gadisa A. , Mammo W. , Andersson L.  M. , Admassie S. , Zhang F. , Andersson M. R. , Inganäs O. 
Published: November 2007

AbstractA new alternating polyfluorene copolymer poly[2,7‐(9,9‐dioctylfluoren)‐alt‐5,5‐(5′,8′‐di‐2‐thienyl‐(2′,3′‐bis‐(3′′‐octyloxyphenyl)‐quinoxaline))] (APFO‐15), which has electron donor–acceptor–donor units in between the fluorene units, is synthesized and characterized. This polymer has a strong absorption and emission in the visible range of the solar spectrum. Its electroluminescence and photoluminescence emissions extend from about 560 to 900 nm. Moreover, solar cells with efficiencies in excess of 3.5 % have been realized from blends of APFO‐15 and an electron acceptor molecule, a methanofullerene [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM). It has also been observed that electron and hole transport is balanced both in the pure polymer phase and in polymer/PCBM bulk heterojunction films, which makes this material quite attractive for applications in opto‐electronic devices.
Polyvinylpyrrolidone‐Directed Crystallization of ZnO with Tunable Morphology and Bandgap
Authors: Zhang J. , Liu H. , Wang Z. , Ming N. , Li Z. , Biris A. S. 
Published: November 2007

AbstractA novel polyvinylpyrrolidone (PVP)‐directed crystallization route is successfully developed for the shape‐selective synthesis of ZnO particles with distinctive shapes, including monolayer, bilayer, and multilayer structures, gears, capped pots, hemispheres, and bowls, at temperatures as low as 32 °C. This route is based on exploiting a new water/PVP/n‐pentanol system. In the system, PVP can greatly promote ZnO nucleation by binding water and direct ZnO growth by selectively capping the specific ZnO facets, which is confirmed by IR absorption spectra. The bandgap of the ZnO particles is readily tuned by modifying the product morphology by adjusting the PVP chain length, PVP amount, water volume, and reaction temperature. The remarkable ZnO structures and the biomimetic method demonstrated here not only expand the structures and applications of ZnO but also provide a new approach to explore the unusual structures for novel physicochemical properties and technological applications. Furthermore, the novel ZnO/Au/ZnO sandwich structure is successfully fabricated by inserting a Au plate into the bilayer ZnO structure.
Synthesis and Characterization of Discrete Nickel Phosphide Nanoparticles: Effect of Surface Ligation Chemistry on Catalytic Hydrodesulfurization of Thiophene
Authors: Senevirathne K. , Burns A. W. , Bussell M. E. , Brock S. L. 
Published: November 2007

AbstractDiscrete, unsupported nanoparticles of Ni2P have been prepared by using a solution‐phase method with bis(1,5‐cyclooctadiene)nickel(0) [Ni(COD)2] as the nickel source and trioctylphosphine (TOP) as the phosphorus source in the presence of the coordinating solvent trioctylphosphine oxide (TOPO). Ni2P nanoparticles prepared at 345 °C have an average crystallite size of 10.2 ± 0.7 nm and are capped with TOP and/or TOPO coordinating agents. The surface of the Ni2P nanoparticles can be modified by washing with CHCl3or by exchanging TOP/TOPO groups with mercaptoundecanoic acid (MUA). The surface areas of these nanoparticles are on the order of 30–70 m2g–1. As‐prepared and MUA‐capped nanoparticles undergo a phase transformation at 370 °C under reducing conditions, but CHCl3‐washed Ni2P nanoparticles retain the Ni2P structure. CHCl3‐washed and MUA‐capped nanoparticles exhibit higher HDS catalytic activity than as‐prepared nanoparticles or unsupported Ni2P prepared by temperature‐programmed reduction of a phosphate precursor. The surface modifications have a clear effect on the catalytic activity as well as the thermal stability of Ni2P nanoparticles under reducing conditions.
Evaluation of Ligands for Ketone Reduction by Asymmetric Hydride Transfer in Water by Multi‐Substrate Screening
Authors: Zeror Saoussen , Collin Jacqueline , Fiaud Jean‐Claude , Zouioueche Louisa Aribi 
Published: November 2007

AbstractVarious ligands for the ruthenium‐catalyzed enantioselective reduction of ketones in water have been investigated. Multi‐substrate reactions have been carried out for the comparison of various proline amides and aminoalcohol ligands. Two sets of six aromatic ketones have been selected in order to evaluate the enantiomeric excesses of all the resulting alcohols by a single chromatographic analysis. The proline amide derivative prepared from (1R,2S)‐cis‐aminoindanol revealed as the best ligand for most of the ketones used in the multi‐substrate reductions. This ligand has been employed for the enantioselective reduction of a variety of other aromatic ketones and in all cases the enantiomeric excesses were improved compared to those obtained with phenylprolineamide used in our previous work.
Selective Light Supported Oxidation of Hexoses Using Air as Oxidant – Synthesis of Tetrahydroxyazepanes
Authors: Gassama Abdoulaye , Hoffmann Norbert 
Published: November 2007

AbstractUnprotected alkyl glycosides have been oxidized using air as oxidant and copper(I) chloride/TEMPO as the catalytic system. The primary hydroxy group in the 6 position is selectively transformed into an aldehyde equivalent. The process was optimized by irradiation with visible light. Without further purification and with high yields, the resulting lactols have been transformed into tetrahydroxyazepane.
Synthesis of Versatile Building Blocks through Asymmetric Hydrogenation of Functionalized Itaconic Acid Mono‐Esters
Authors: Hekking Koen F. W. , Lefort Laurent , de Vries André H. M. , van Delft Floris L. , Schoemaker Hans E. , de Vries Johannes G. , Rutjes Floris P. J. T. 
Published: November 2007

AbstractThe rhodium‐catalyzed asymmetric hydrogenation of several β‐substituted itaconic acid monoesters, using a library of monodentate phosphoramidite and phosphite ligands is described. Two β‐alkyl‐substituted substrates were readily hydrogenated by the rhodium complex Rh(COD)2BF4 in combination with (S)‐PipPhos as a ligand resulting in ees of 99 %. In contrast, the corresponding more hindered β‐aryl‐substituted substrates did not exhibit acceptable enantioselectivities under these conditions. However, the use of a 48‐membered ligand library led to the identification of several suitable ligands for these substrates, resulting in ees of 89–99 %. The resulting optically active succinic acid derivatives are potentially useful building blocks for more elaborate compounds, because of the ability to differentiate between the carboxylic acid and the ester groups on either side of the molecule.
The impact of group fissions on genetic structure in Native South America and implications for human evolution
Authors: Hunley K.L. , Spence J.E. , Merriwether D.A. 
Published: November 2007

AbstractIn a series of publications beginning in the 1960s, Neel and colleagues suggested that genetically nonrandom, or “lineal”, population fissions contributed to genetic structure in ancient human groups. The authors reached this conclusion by studying the genetic consequences of village fissions among the Yanomamo, a Native South American group thought to have been relatively unaffected by European contact and, therefore, representative of the human past. On the basis of ethnographic accounts and pedigree data, they further concluded that patrilineal relationships were particularly important in shaping the genetic structure of villages following fissions. This study reexamines the genetic consequences of village fissions using autosomal STRs, Y‐chromosome STRs, and mitochondrial DNA sequences collected from large samples of individuals from multiple Yanomamo villages. Our analyses of the autosomal STRs replicate the previous finding that village fissions have produced substantial genetic structure among the Yanomamo. However, our analyses of Y‐chromosome STRs and mtDNA d‐loop polymorphisms suggest that other population processes, including village movements, inter‐village migration, and polygynous marriage, affect genetic structure in ways not predicted by a simple model of patrilineal fissions. We discuss the broader implications of population fissions for human evolution and the suitability of using the Yanomamo as a model for the human past. Am J Phys Anthropol, 2008. © 2007 Wiley‐Liss, Inc.
Brief communication: Comparison of methods for estimating chronological age at linear enamel formation on anterior dentition
Authors: Martin Sarah A. , Guatelli‐Steinberg Debbie , Sciulli Paul W. , Walker Phillip L. 
Published: November 2007

AbstractLinear enamel hypoplasia (LEH) is an enamel defect that records the effects of physiological stress on tooth formation. Estimating the age at which LEH defects form is integral to the reconstruction of population health in bioarcheological studies. Two principal methods for aging LEH defects have been introduced in the literature. The conventional approach employs regression equations based on a linear model of tooth growth. The newer, Reid and Dean [Am J Phys Anthropol 113 (2000) 135–139] approach, is based upon a histologically derived curvilinear model of enamel development and therefore likely provides more accurate age estimates. However, the extent to which the Reid and Dean method produces estimated ages at defect formation differing from those of the regression equations has not, until now, been determined. This study quantifies the differences between these two methods. Evaluating the degree to which these methods differ is essential for interpreting the accuracy of LEH age estimates given in previous bioarcheological studies. Age estimates of LEH defects on 338 anterior teeth from the Hamann–Todd osteological sample were calculated using both methods. The resulting estimated ages were compared through a randomized block ANOVA. However, the mean differences between the estimated ages yielded by both methods range from 4 months or less depending on the tooth type with an overall average of 2.63 months. The discussion focuses on the degree to which this difference affects answers to bioarcheological questions. Am J Phys Anthropol, 2008. © 2007 Wiley‐Liss, Inc.
Höhere Acene: vielseitige organische Halbleiter
Authors: Anthony John E. 
Published: November 2007

AbstractAcene werden wegen ihrer einzigartigen elektronischen Eigenschaften, die auf der Topologie ihrer π‐Systeme beruhen, seit langem untersucht. Berichte über die bemerkenswerten Halbleitereigenschaften höherer Homologe haben in letzter Zeit zu verstärkten Forschungsaktivitäten geführt. Es wurden neue Verfahren zur Synthese, Funktionalisierung und Reinigung sowie zur Herstellung organoelektronischer Bauteile entwickelt. Durch Untersuchungen an hochreinen Acen‐Einkristallen wurden die charakteristischen elektronischen Eigenschaften und Kenngrößen für die Beurteilung von Dünnschichtbauteilen ermittelt. Um die Verarbeitbarkeit in Lösung zu verbessern, wurden neuartige Funktionalisierungsmethoden entwickelt. Die für elektronische Anwendungen erwünschten Eigenschaften nichtfunktionalisierter Acene bleiben bei der Funktionalisierung erhalten. Mit diesen Verfahren wurden kürzlich Derivate höherer Acene als Pentacen, die zuvor kaum zugänglich waren, erhalten, sodass Struktur‐Eigenschafts‐Beziehungen untersucht werden konnten.
Polymer–Fullerene Composite Solar Cells
Authors: Thompson Barry C. , Fréchet Jean M. J. 
Published: November 2007

AbstractFossil fuel alternatives, such as solar energy, are moving to the forefront in a variety of research fields. Polymer‐based organic photovoltaic systems hold the promise for a cost‐effective, lightweight solar energy conversion platform, which could benefit from simple solution processing of the active layer. The function of such excitonic solar cells is based on photoinduced electron transfer from a donor to an acceptor. Fullerenes have become the ubiquitous acceptors because of their high electron affinity and ability to transport charge effectively. The most effective solar cells have been made from bicontinuous polymer–fullerene composites, or so‐called bulk heterojunctions. The best solar cells currently achieve an efficiency of about 5 %, thus significant advances in the fundamental understanding of the complex interplay between the active layer morphology and electronic properties are required if this technology is to find viable application.
Properties of phenol–formaldehyde resin modified with organic acid esters
Authors: Mirski Radosław , Dziurka Dorota , Łęcka Janina 
Published: November 2007

AbstractProperties of liquid and cured phenol–formaldehyde (PF) resin modified with esters were analyzed in this study. Esters with different carbon chain lengths, both in the acid and alcohol groups, were applied in the experiments. It was found that the modification of phenolic resin with applied esters does not deteriorate its pot life at the temperature of 20°C. It results in an increase of its reactivity at higher temperatures, manifested in the shortening of gel time at 130°C and a decrease of activation energy. Results of FTIR tests of polycondensed modified PF resin showed that products of alkali hydrolysis of esters not only catalyze the curing reaction of resin, but also become embedded in its structure. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and Anticonvulsant Activity of Some N‐Phenyl‐2‐phtalimidoethanesulfonamide Derivatives
Authors: Akgul Ozlem , Sultan Kilic Fatma , Erol Kevser , Pabuccuoglu Varol 
Published: November 2007

AbstractIn this study, inspired by the structures of the taltrimide, 2‐phthalimidoethanesulphonamide, and the anilide pharmacophore known to be synthetically produced anticonvulsant compounds, fifteen N‐phenyl‐2‐phtalimidoethanesulfonamide derivatives bearing substituents with diverse electronic and hydrophobic features on N‐phenyl ring were synthesized. The structural confirmation of the title compounds was achieved by interpretation of spectral and analytical data. The anticonvulsant activity of the title compounds was determined against maximal electroshock seizure in mice at a dose level of 100 mg/kg. The preliminary screening results indicated that the exchange of the N‐isopropyl moiety for an N‐phenyl ring in the taltrimide molecule abolished the anticonvulsant activity. However, introducing certain substituents, such as nitro, methyl, and chloro, into the N‐phenyl ring lead to more active compounds in comparison to the unsubstituted derivatives.
Setup and dosimetry for exposure of human skin in vivo to RF‐EMF at 900 MHz
Authors: Toivonen Tommi , Toivo Tim , Puranen Lauri , Jokela Kari 
Published: November 2007

AbstractThe aim of this study was a dosimetrical analysis of an experimental setup used in the exposure of 10 female volunteers to GSM 900 radiation. The exposure was carried out by irradiating a small region of the right forearms of the volunteers for 1 h, after which biopsies were taken from the exposed skin for protein analysis. The source of irradiation was a half‐wave dipole fed with a computer controlled GSM phone. The specific absorption rate (SAR) induced in the skin biopsy was assessed by computer simulations. The numerical model of the arm consisted of a muscle tissue simulating cylinder covered with thin skin (1 mm) and fat (3 mm) layers. The simulation models were validated by measurements with a homogeneous cylindrical liquid phantom. The average SAR value in the biopsy was 1.3 W/kg and the estimated uncertainty ±20% (K = 2). The main source of error was found to be variations in the distance of the forearm from the dipole (10 ± 1 mm). Other significant sources of uncertainty are individual variations of the fat layer and arm thicknesses, and the uncertainty of radio frequency (RF) power measurement. Bioelectromagnetics 29:207–212, 2008. © 2007 Wiley‐Liss, Inc.
Cognitive impairment in rats after long‐term exposure to GSM‐900 mobile phone radiation
Authors: Nittby Henrietta , Grafström Gustav , Tian Dong Ping , Malmgren Lars , Brun Arne , Persson Bertil R.R. , Salford Leif G. , Eberhardt Jacob 
Published: November 2007

AbstractConsidering the frequent use of mobile phones, we have directed attention to possible implications on cognitive functions. In this study we investigated in a rat model the long‐term effects of protracted exposure to Global System for Mobile Communication‐900 MHz (GSM‐900) radiation. Out of a total of 56 rats, 32 were exposed for 2 h each week for 55 weeks to radio‐frequency electromagnetic radiation at different SAR levels (0.6 and 60 mW/kg at the initiation of the experimental period) emitted by a (GSM‐900) test phone. Sixteen animals were sham exposed and eight animals were cage controls, which never left the animal house. After this protracted exposure, GSM‐900 exposed rats were compared to sham exposed controls. Effects on exploratory behaviour were evaluated in the open‐field test, in which no difference was seen. Effects on cognitive functions were evaluated in the episodic‐like memory test. In our study, GSM exposed rats had impaired memory for objects and their temporal order of presentation, compared to sham exposed controls (P = 0.02). Detecting the place in which an object was presented was not affected by GSM exposure. Our results suggest significantly reduced memory functions in rats after GSM microwave exposure (P = 0.02). Bioelectromagnetics 29:219–232, 2008. © 2007 Wiley‐Liss, Inc.
Anwendung der Zuverlässigkeitsanalyse auf Messungen mit zerstörungsfreien Prüfverfahren am Beispiel der Tunnelinnenschalenprüfung
Authors: Taffe Alexander , Gehlen Christoph 
Published: November 2007

AbstractBemessungsregeln werden im Bauwesen derzeit auf der Grundlage der so genannten Zuverlässigkeitsanalyse entwickelt. Auf ihr ist auch das Sicherheitskonzept der EUROCODES gegründet. Seit ungefähr einem Jahrzehnt werden auch Dauerhaftigkeitsanalysen nach dieser Vorgehensweise durchgeführt. In diesem Beitrag wird gezeigt, wie Methoden der Zuverlässigkeitsanalyse nun auch auf Messaufgaben angewandt werden können. Dies wird am Beispiel der zerstörungsfreien Prüfung von Tunnelinnenschalen mit dem Ultraschallecho‐Verfahren erläutert, dessen Anwendung in der Richtlinie RI‐ZFP‐TU des Bundesministeriums für Verkehr, Bau und Stadtentwicklung geregelt ist. Es wird gezeigt, wie Messdaten weitergehend ausgewertet werden können und welche Rückschlüsse daraus gezogen werden können. Damit kann die Eignung zerstörungsfreier Prüfverfahren im Bauwesen bezogen auf die vorhandenen Randbedingungen der Prüfaufgabe auch quantitativ angegeben werden.
Elementwände im drückenden Grundwasser. Diskrepanz zwischen Theorie und Praxis?
Authors: Hohmann Rainer 
Published: November 2007

AbstractElementwände im drückenden Grundwasser erfordern eine besondere Sorgfalt bei der Planung, Ausführung und Überwachung. Voraussetzung für die Funktionsfähigkeit von Elementwänden im drückenden Grundwasser ist, dass die hohen Anforderungen der WU‐Richtlinie an die Planung und Ausführung, aber auch an die Herstellung der Elementwandplatten im Werk auch umgesetzt werden. Wie bei wasserundurchlässigen Bauwerken aus Ortbeton sind auch bei WU‐Bauwerken in Elementwandbauweise Fugen und Durchdringungen mögliche Schwachstellen, die fachgerecht und dauerhaft abzudichten sind. Häufig zeigt sich aber eine deutliche Diskrepanz zwischen Theorie und Praxis. In dem Beitrag werden grundlegende Zusammenhänge aufgezeigt, typische Fehler erläutert und Hinweise zur Fehlervermeidung gegeben.
Examining the effectiveness of an intervention designed for the restoration of competency to stand trial
Authors: Mueller Crystal , Wylie A. Michael 
Published: November 2007

AbstractThis study examined the effectiveness of the Fitness Game, an intervention created for the restoration of competency to stand trial. Of 28 participants who completed either the experimental or control intervention at Hawai'i State Hospital (HSH), it was found that both groups had significant pretest to posttest improvements on Understanding and Appreciation subsets of the MacArthur Competence Assessment Tool—Criminal Adjudication (MacCAT‐CA). However, there was no statistically significant difference between the groups on competency measures, indicating that the Fitness Game was not significantly more effective at restoring competency than non‐legal programming. In other words, individuals committed to a psychiatric hospital for care and treatment were as likely to improve as those receiving additional specialized competency restoration treatment. Copyright © 2007 John Wiley & Sons, Ltd.