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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

The fundamental plane of EDisCS galaxies (Corrigendum)

Saglia, R. P., Sánchez-Blázquez, P., Bender, R., Simard, L., Desai, V., Aragón-Salamanca, A., Milvang-Jensen, B., Halliday, C., Jablonka, P., Noll, S., Poggianti, B., Clowe, D. I., De Lucia, G., Pelló, R., Rudnick, G., Valentinuzzi, T., White, S. D. M., Zaritsky, D. 19 December 2016 (has links)
We discovered a mistake in Eqs. (7) and (10) of Saglia et al. (2010, A&A, 524, A6), which propagates to Tables 8 and 9 and Fig. 25. We revise the tables, the figure and the affected statements in the paper. As a result, the reduction in the luminosity evolution due to the effects of the size and velocity dispersion evolution is smaller than claimed in Saglia et al. (2010).
232

End-user training of post-graduate students in the use of CD-ROM database with special reference to the University of the North

20 November 2014 (has links)
M.A. (Information Science) / This research investigated the problem of multiple bibliographic interfaces that end-users face when conducting searches. A situation analysis was conducted which provided a profile of the situation under investigation. Based on the results of the analysis an end-user training programme for adoption by subject reference librarians at the University of the North Library with regard to bibliographic CD-ROM databases is formulated. This programme is proposed to address problems that end-users experience with these databases and in the process to improve their search abilities. Finally, areas for further investigation with regard to the situation, learner and learning situation are also suggested.
233

A Theoretical and Empirical Analysis of the Impact of the Digital Age on the Music Industry

Michel, Norbert 19 December 2003 (has links)
We present an in-depth analysis of the music industry and use our findings to judge the practical assumptions and design of an original theoretical model. The model is in three stages, where, in a Hotelling-type framework, the last agents to act are consumers who choose between copying, purchasing, or staying out of the market for music. Prior to the last stage, the record label chooses its profit maximizing price and, in the first stage, we incorporate the artist-label bargaining agreement into a theoretical framework using the Nash cooperative bargaining solution. The current structure of the music industry is a combination of the oligopoly and monopolistic competition models, consisting of five major labels and many independents. Despite major labels' advantage in large-scale distribution, we argue that digital downloading has the potential to radically alter the current industry structure, and that artists would be unable to sell their music in such an environment without enforceable copyrights. Our model assumes that the most important determinants of CD and copy demand are consumers' tastes and transaction costs of copying, CD prices, and the substitutability between CDs and copies. We hypothesize that Internet file-sharing has been undertaken by both consumers who were previously not in the market, and by those who decided to copy rather than buy. In regard to firm strategy, the model suggests that labels could increase the sales of CDs by trying to increase consumers' taste for music, perhaps by reducing the price of CDs. Our model also predicts a positive relationship between artists' optimal share of album sales and their bargaining power, as well as a negative relationship between artists' optimal share and their risk aversion. Since lowering the reliance on labels for distribution would increase artists' bargaining power, our model predicts that artists' share of profits should increase as legitimate digital distribution gains prominence. We also provide empirical testing of our hypothesis that some music file-sharing has been done by consumers frequently not in the market. After examining consumers' expenditures and aggregate industry sales, we are unable to reject our hypothesis
234

Theoretical investigations on the spectroscopy of molecular aggregates / Theoretische Untersuchungen zur Spektroskopie von Molekülaggregaten

Seibt, Joachim January 2009 (has links) (PDF)
Die spektroskopischen Eigenschaften von Molekülaggregaten wurden mittels quantendynamischer Berechnungen untersucht. Hierbei wurden sowohl lineare als auch nichtlineare Spektroskopietechniken einbezogen. Zur Simulation von Absorptions- und CD-Spektroskopie wurden Kopplungseffekte sowie die relative Orientierung der Monomer-Einheiten in den Modellen berücksichtigt, um gemessene Spektren reproduzieren und so die entsprechenden Parameter zu bestimmen. Zur genaueren Beschreibung wurden auch Ergebnisse quantenchemischer Rechnungen verwendet. Darüber hinaus wurden Untersuchungen zur nichtlinearen optischen Spektroskopie an Dimeren durchgeführt. / The spectroscopic properties of molecular aggregates have been investigated by means of quantum dynamical calculations. Thereby both linear and nonlinear spectroscopic techniques have been taken into account. For the simulation of absorption and CD-spectra, coupling effects were regarded as well as the relative orientation of the monomer units in order to determine the parameters by reproducing measured spectra. For a more detailled description, results from quantum chemical calculations have also been included. Furthermore, investigations on nonlinear spectroscopy of molecular dimers have been performed.
235

Validität tissue-microarray-basierter Immunphänotypisierung bei Hodgkin-Lymphomen

Schnabel, Katrin Anne January 2009 (has links) (PDF)
Die histologische Technik der Tissue-Microarrays ist eine sehr effiziente Methode, um eine große Anzahl auch heterogener Lymphome wie des Hodgkin-Lymphoms bei hohem Durchsatz unter homogenen Färbebedingungen zu untersuchen. Die vorliegende Arbeit konnte zeigen, dass ein Probeschnitt zur vorherigen Auswahl stanzwürdigen Tumorareals nicht nötig ist. Die so genannte Blindstanzung trug weniger als einen Prozentpunkt (0,9%) zum Verlust der auswertbaren Fälle bei. Dennoch war bei einzelnen Parametern (LMP1 und EBER) ein hoher Gewebeverlust zu beobachten. In einer Stichprobe von 2696 Stanzen waren es 24% (631 Stanzen) bedingt durch die Färbetechnik, aber auch durch unterschiedliche Vorbehandlungen und Originalfixationen des Probematerials. In dieser Studie wurden 1212 Fälle zur Immuntypisierung von Tumorzellen des klassischen und nodulär lymphozyten-prädominanten Hodgkin-Lymphoms untersucht. Die Fälle von c-HL wiesen eine häufige Expression von CD30- und CD15-Oberflächenmarkern und kaum B-Zell-Marker auf, während im NLP-HL die Expression in umgekehrter Häufigkeit vorlag. Diese bisher größte Untersuchung von T-Zell-Markern an H-/RS-Zellen, erstmalig auch an NLP-HL, ergab eine bis zu 6-fach höhere Frequenz in der NLP-HL bei häufigerer B-Zell-Marker-Expression. Die in der Literatur beschriebene Rangordnung der Expressionshäufigkeit von Oberflächenantigenen im c-HL (CD2 > CD4 > CD3 > CD5 > CD8) wurde bestätigt und wich nur in den Markern CD3 und CD5 ab: Perforin >> CD4 > CD5 > CD3 > CD8 > GranzymB > TIA-1 > CD7. Tzankov et al. [45] fanden in ihrer Untersuchung mit 259 c-HL-Fällen eine Häufigkeit von 5% T-Zell-Marker-Expression. Die vorliegende Arbeit mit 1147 untersuchten c-HL-Fällen kam zum Ergebnis einer deutlich höheren T-Zell-Marker-Expressionshäufigkeit von 20,1%. Der pathophysiologische Mechanismus der T-Zell-Marker-Expression ist bis heute noch unklar, könnte aber als eine alternative Signalkaskade zur Aufrechterhaltung des Zellzyklus unter geändertem Zellmilieu gedeutet werden. Ein weiterer Fokus dieser Arbeit betraf die Gruppe der Studienteilnehmer 60 Jahre und älter, um Hinweisen auf das „age-related“ EBV-associated Lymphom und der Rolle der Mikrosatelliten-Instabilität nachzugehen. So fand sich eine signifikante Häufung von Markern für eine EBV-Infektion (EBER, LMP1) in der Gruppe der über 60-Jährigen. Die Expression von DNA-Reparaturenzymen, deren Ausbleiben auf Mikrosatelliten-Instabilität gedeutet hätte, unterschied sich zwischen jüngeren und älteren Studienteilnehmern nicht.
236

INTERAÇÕES DE TROCA PARA VIZINHOS DISTANTES POR DEGRAUS DE MAGNETIZAÇÃO NO Cd(1-x)Mn(x)Se

Merino, Rafael Alejandro Cajacuri 06 March 2002 (has links)
Esta dissertação estuda as constantes de troca para vizinhos distantes no semicondutor magnético diluído Cd(1-x)Mn(x)Se, que tem a estrutura da wurtzita. O método dos degraus de magnetização foi empregado, a partir de medidas de magnetização a 20 mK e campos magnéticos de até 5 Tesla. Mediram-se pela primeira vez os valores de quatro constantes de troca antiferromagnéticas para vizinhos distantes (além das duas constantes conhecidas para primeiros vizinhos). Os valores obtidos são: J(3) /kB =-0.35 ± 0.01K, J(4) /kB =-0.20 ± 0.01K, J(5) /kB =-0.10 ± 0.01K e J(6) /kB = -0.08 ± 0.01K.. Para a identificação dos pares correspondentes às interações de troca medidas utilizou-se a estatística de clusters supondo uma distribuição aleatória dos íons de Mn. Simulações teóricas que consideram até clusters de tipo quarteto na estrutura hcp dos cátions foram implementadas. Uma identificação completa não foi possível por causa de coincidências entre populações de pares diferentes que ocorrem na estrutura deste material. Os resultados apresentam uma grande similaridade com os observados nos compostos cúbicos da mesma família
237

Projeto CD-ROM Interagyn: História e Memória de Goiânia

Moreno, Enio dos Santos 16 January 2008 (has links)
Made available in DSpace on 2016-08-10T10:36:52Z (GMT). No. of bitstreams: 1 ENIO DOS SANTOS.pdf: 14195974 bytes, checksum: c01c685a5b57e657bcae19639e647f5c (MD5) Previous issue date: 2008-01-16 / Por meio dos recursos da antropologia visual, pretende-se fomentar um diálogo entre o processo histórico, os conceitos de memória, fotografia e cultura, para compreender as relações de passado/presente, as modificações ocorridas nesse lapso de tempo, mostrando para os usuários do CD-ROM INTERAGYN que o trabalho da memória é voltar no tempo e evocar lembranças e momentos significativos que servem para refletir acerca do presente e do futuro. As mudanças que ocorrem no mundo a cada dia refletem-se no cotidiano das pessoas. As formas de comunicação, aprendizado e pesquisas sofreram mudanças nas últimas décadas. No ensino de temas culturais e patrimoniais, o uso de ferramentas de multimídia, neste caso, o CD-ROM, acrescenta maior agilidade ao processo de aprendizagem, garantindo maior acesso às pesquisas com possibilidades interativas com maior rapidez na divulgação das mensagens. O roteiro deste CD-ROM busca promover a participação de indivíduos e da comunidade de diferentes instituições como as escolas, possibilitando conhecimentos didáticos, dando a oportunidade de gerarem discussões e ações ativas nas questões patrimoniais, estabelecendo uma maior integração social e cultural desses grupos e deles com o centro histórico de Goiânia e o patrimônio cultural local.
238

Quantenchemische Studien der Chiroptischen Eigenschaften ausgedehnter π-Systeme sowie Beiträge zu SpecDis / Quantum-Chemical Studies of the Chiroptical Properties of Extended π Systems and Contributions to SpecDis

Schaumlöffel, Anu Lena January 2014 (has links) (PDF)
Für die Aufklärung der absoluten Stereostruktur von chiralen Molekülen, die ein Chromophorsystem besitzen, hat sich die Kombination der experimentellen und theoretischen Spektroskopie des elektronischen Circulardichroismus (ECD) als Methode bewährt. In der vorliegenden Arbeit wurden die chiroptischen Eigenschaften von Bisbibenzyl-Makrocyclen, Mono- und Bis(cycloketo)porphyrinen, der Mohnblütenpigmente Nudicaulin I und II sowie von Bordipyrrol-Dimeren mit quantenchemischen Methoden untersucht. Zu diesem Zweck wurden verschiedene dichtefunktionaltheoretische (DFT) Ansätze und post-HF-Methoden, wie z. B. der Coupled-Cluster-Ansatz RI-CC2, bezüglich ihrer Eignung, die Grund- und angeregten Zustände (UV/vis- und ECD-Eigenschaften) der einzelnen Verbindungen korrekt wiederzugeben, evaluiert. Da bei quantenchemischen UV- und ECD-Rechnungen an ausgedehnten π-Systemen aufgrund energetisch nah beieinander liegender Anregungen die Wahrscheinlichkeit für ghost states und charge-transfer-Übergänge sowie Multireferenz-Problematiken steigt, wurden diese Aspekte genauer betrachtet. Die ersten zwei Phänomene lassen sich bereits auf TD-DFT-Niveau durch genaue Analyse der theoretischen spektroskopischen Daten ermitteln und unter Umständen durch entsprechend korrigierte Funktionale sogar sehr gut beschreiben. Im Gegensatz dazu können Doppelanregungsanteile überhaupt erst durch Rechnungen mit geeigneten Methoden, wie z. B. das hier verwendete SORCI-Verfahren, erfasst werden. Zusätzlich wurde das zur Auswertung von UV und ECD-Daten entwickelte Programm SpecDis um Funktionalitäten erweitert, welche die Berechnung des Übereinstimmungsgrades zweier UV- bzw. ECD-Kurven ermöglichen, und dadurch ein zusätzliches quantitatives Kriterium für die Verlässlichkeit des Spektrenvergleichs und folglich für die Zuordnung der absoluten Konfiguration bieten. / For the elucidation of the absolute stereostructure of chiral molecules possessing a chromophore, the combination of experimental and theoretical spectroscopy of the electronic circular dichroism (ECD) has proven a valuable tool. In the present work, the chiroptical properties of bisbibenzyl macrocycles, mono- and bis(cycloketo)porphyrins, the poppy-petal pigments nudicaulins I and II, and boron-dipyrrole dimers were investigated with quantum-chemical methods. For this purpose, different density-functional and post-HF methods, for example the coupled-cluster approach RI-CC2, were evaluated regarding their suitability to correctly describe the ground and exited states (UV/vis and ECD properties) of each compound. Since the probability of ghost states, charge-transfer transitions, and multi-reference problems increases for quantum-chemical UV and CD calculations of extended π systems due to energetically close-lying excitations, these aspects were closely examined. The first two phenomena can be detected on TD-DFT level of theory by a thorough analysis of the theoretical spectroscopic data, and can in some cases even be described quite well by specially corrected functionals. By contrast, double excitations can only be included in the calculations by using suitable methods, e.g. the herein used SORCI approach. Additionally, functionalities were added to the program SpecDis which allow for the calculation of the degree of similarity of either two UV or ECD curves, and thus, offer an additional quantitative measure for the comparison of spectra and, in consequence, for the reliability of the assignment of an absolute configuration.
239

Studies of CD44 variant isoform expression and function on activated human peripheral blood mononuclear cells and in renal transplantation

Varelias, Antiopi. January 2001 (has links) (PDF)
Errata slip inserted at back "August 2001." Includes bibliographical references (leaves 254-296)
240

Studies of CD44 variant isoform expression and function on activated human peripheral blood mononuclear cells and in renal transplantation / Antiopi Varelias.

Varelias, Antiopi January 2001 (has links)
Errata slip inserted at back / "August 2001." / Includes bibliographical references (leaves 254-296) / xxviii, 296, [9] leaves : charts (some col.), plates (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Medicine, 2001

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