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Modeling J /Psi production and absorption in a microscopic nonequilibrium approach
(1999)
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Christian Spieles
Ramona Vogt
Lars Gerland
Steffen A. Bass
Marcus Bleicher
Horst Stöcker
Walter Greiner
- Charmonium production and absorption in heavy ion collisions is studied with the Ultrarelativisitic Quantum Molecular Dynamics model. We compare the scenario of universal and time independent color-octet dissociation cross sections with one of distinct color-singlet J/psi, psi 2 and CHIc states, evolving from small, color transparent configurations to their asymptotic sizes. The measured J/psi production cross sections in pA and AB collisions at SPS energies are consistent with both purely hadronic scenarios. The predicted rapidity dependence of J/psi suppression can be used to discriminate between the two experimentally. The importance of interactions with secondary hadrons and the applicability of thermal reaction kinetics to J/psi absorption are in- vestigated. We discuss the e ect of nuclear stopping and the role of leading hadrons. The dependence of the 2/J/psi ratio on the model assumptions and the possible influence of refeeding processes is also studied.
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Particle number fluctuations in high energy nucleus-nucleus collisions from microscopic transport approaches
(2005)
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Volodymyr P. Konchakovski
Stephane Häussler
Mark I. Gorenstein
Elena L. Bratkovskaya
Marcus Bleicher
Horst Stöcker
- Event-by-event multiplicity fluctuations in nucleus-nucleus collisions are studied within the HSD and UrQMD transport models. The scaled variances of negative, positive, and all charged hadrons in Pb+Pb at 158 AGeV are analyzed in comparison to the data from the NA49 Collaboration. We find a dominant role of the fluctuations in the nucleon participant number for the final hadron multiplicity fluctuations. This fact can be used to check di erent scenarios of nucleus-nucleus collisions by measuring the final multiplicity fluctuations as a function of collision centrality. The analysis reveals surprising e ects in the recent NA49 data which indicate a rather strong mixing of the projectile and target hadron production sources even in peripheral collisions. PACS numbers: 25.75.-q,25.75.Gz,24.60.-k
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Mediendiskurs und pädagogische Reflexion in Indien: Zwischen Vision und Alltag. Versuch einer Rekonstruktion und Analyse pädagogischer Argumentationskulturen am Beispiel Indiens
(1999)
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Iris Clemens
- Am Beispiel der erziehungswissenschaftlichen Diskussion über „Neue Medien“ wird in kulturvergleichender Perspektive der Versuch einer Rekonstruktion der latenten Diskursmuster der Pädagogik und ihrer Funktionen in Indien unternommen. Grundlage der Analyse ist dabei nach intensiven Literaturrecherchen und Expertengesprächen vor allem die Zeitschrift University News (herausgegeben von der Association of Indian Universities) als aktuelles Forum pädagogischer und bildungsrelevanter Themen. Unter Rekurs auf den Bildungsreport der UNESCO, Learning: The Treasure Within, der im pädagogischen Diskurs in Indien eine exponierte Position einnimmt, werden Kategorien zur Strukturierung entwickelt, die dann vor allem über zwei Dimensionen - Programmatik statt Forschung und Theorie und Technologieorientierung und Trivialisierung – analytisch aufgeschlüsselt werden. Die Interpretation greift dabei hauptsächlich auf systemtheoretische und konstruktivistische Ansätze zurück. Die abschließende Frage nach den Funktionen des Diskurses wird auf der Folie der Vaihinger’schen Philosophie des „As Ob“ verfolgt. Der dem Diskurs inhärente fiktionale Charakter wird dabei als generatives Muster im Rahmen von Ausdifferenzierungsprozessen des Erziehungssystems in Indien interpretiert.
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Die Grenzbewohner, oder: Die Beweinte von Wish-Ton-Wish
(1858)
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James Fenimore Cooper
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Denkschrift der Kronstädter Handels- und Gewerbe-Kammer über die Führung einer Eisenbahn von Kronstadt in die Walachei bis an die Donau
(1855)
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Franz Voss
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Schritte zur Aufhellung des Sprachräthsels betreffend indo-europäische Sprachwurzeln : entwickelt nach physiologischen Principien
(1868)
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Jacob Walser
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Accessory subunits of complex I from Yarrowia lipolytica
(2005)
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Albina Abdrakhmanova
- Mitochondial NADH:ubiquinone oxidoreductase (complex I) the largest multiprotein enzyme of the respiratory chain, catalyses the transfer of two electrons from NADH to ubiquinone, coupled to the translocation of four protons across the membrane. In addition to the 14 strictly conserved central subunits it contains a variable number of accessory subunits. At present, the best characterized enzyme is complex I from bovine heart with a molecular mass of about 980 kDa and 32 accessory proteins. In this study, the subunit composition of mitochondrial complex I from the aerobic yeast Y. lipolytica has been analysed by a combination of proteomic and genomic approaches. The sequences of 37 complex I subunits were identified. The sum of their individual molecular masses (about 930 kDa) was consistent with the native molecular weight of approximately 900 kDa for Y. lipolytica complex I obtained by BN-PAGE. A genomic analysis with Y. lipolytica and other eukaryotic databases to search for homologues of complex I subunits revealed 31 conserved proteins among the examined species. A novel protein named “X” was found in purified Y. lipolytica complex I by MALDI-MS. This protein exhibits homology to the thiosulfate sulfurtransferase enzyme referred to as rhodanese. The finding of a rhodanese-like protein in isolated complex I of Y. lipolytica allows to assume a special regulatory mechanism of complex I activity through control of the status of its iron-sulfur clusters. The second part of this study was aimed at investigating the possible role of one of these extra subunits, 39 kDa (NUEM) subunit which is related to the SDRs-enzyme family. The members of this family function in different redox and isomerization reactions and contain a conserved NAD(P)H-binding site. It was proposed that the 39 kDa subunit may be involved in a biosynthetic pathway, but the role of this subunit in complex I is unknown. In contrast to the situation in N. crassa, deletion of the 39 kDa encoding gene in Y. lipolytica led to the absence of fully assembled complex I. This result might indicate a different pathway of complex I assembly in both organisms. Several site-directed mutations were generated in the nucleotide binding motif. These had either no effect on enzyme activity and NADPH binding, or prevented complex I assembly. Mutations of arginine-65 that is located at the end of the second b-strand and responsible for selective interaction with the 2’-phosphate group of NADPH retained complex I activity in mitochondrial membranes but the affinity for the cofactor was markedly decreased. Purification of complex I from mutants resulted in decrease or loss of ubiquinone reductase activity. It is very likely that replacement of R65 not only led to a decrease in affinity for NADPH but also caused instability of the enzyme due to steric changes in the 39 kDa subunit. These data indicate that NADPH bound to the 39 kDa subunit (NUEM) is not essential for complex I activity, but probably involved in complex I assembly in Y. lipolytica.
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Ludwig Tieck : Erinnerungen aus dem Leben des Dichters nach dessen mündlichen und schriftlichen Mittheilungen
(1855)
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Rudolf Köpke
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Expression and meaning in Bach performance and reception : an examination of the B minor Mass on record
(2004)
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Uri Golomb
- This dissertation investigates developments in the performance of J. S. Bach’s music in the second half of the 20th century, as reflected in recordings of the Mass in B Minor, BWV 232. It places particular emphasis on issues relating to concepts of expression through performance. Between the 1950s and the 1980s, most Bach performers shared a partial consensus as to what constitutes expression in performance (e.g., intense sound; wide dynamic range; rubato). Arguments against the application of such techniques to Bach’s works were often linked with the view that his music is more “objective” than later repertoires; or, alternatively, that expressive elements in Bach’s music are self-sufficient, and should be not be intensified in performance. Historically-informed performance (HIP), from the late 1960s onwards, has been characterised by greater attention to the inflection of local details (i.e., individual figures and motifs). In terms of expressive intensity, this led to contradictory results. On the one hand, several HIP performances were characterised by a narrow overall dynamic range, light textures, fast tempi and few contrasts; these performances were often considered lightweight. On the other hand, HIP also promoted renewed interest in the practical application of Baroque theories of musical rhetoric, inspiring performances which projected varied intensity within movements. More recently, traditional means of expression have enjoyed renewed prominence. Ostensibly “romantic” features such as broad legati, long-range crescendi and diminuendi, and organic shaping of movements as wholes have been increasingly adopted by HIP musicians. In order to substantiate the narrative outlined above, the significance of the evidence preserved in sound recordings had to be checked against other sources of information. This dissertation is divided into two main parts. The first part focuses on specific “schools” of prominent Bach performers. Complete recordings of the Mass are examined in relation to the biographical and intellectual backgrounds of the main representatives of these schools, their verbally-expressed views on Bach’s music and on their own role as performers, and their style as documented in recordings of other works. The second part examines the performance history of specific movements within the Mass, comparing the interpretations preserved in sound recordings with relevant verbal analyses and commentaries. The dissertation as a whole therefore combines the resources of reception and performance studies. Beyond its specific historical conclusions concerning Bach performance in the post-war era, it also provides specific insights into Bach’s music, its meaning and its role in contemporary culture.
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Zur Frage über den Ursprung der Romänen u. ihrer Sprache : Sylvestergabe für Gönner und Freunde
(1855)
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Johann Karl Schuller