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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.
91

Die Funktion von Bx42/Skip im TGF-beta/Dpp Signal Transduktionsweg

Hachoumi, Mounia el 02 July 2007 (has links)
Die Notwendigkeit von Bx42 für Drosophila Entwicklung und seine Beteiligung an unterschiedlichen zellulären Prozessen wurde mit Hilfe von RNA Interference (RNAi) demonstriert. Das ubiquitäre Ausschalten oder die Reduktion der Bx42 Expression mittels RNAi führte dabei zu embryonaler Letalität. Weiterhin führte eine gewebespezifische Induktion von Bx42 in Abhängigkeit der verwendeten Treiberlinien bei unterschiedlichen Temperaturen zu mehreren verschiedenen adulten Phänotypen. Diese Phänotypen waren die Grundlage für die Annahme, dass Bx42 eine Rolle in der Regulation mehrerer verschiedener Zellsignalwege spielt. In der Tat interagiert Bx42 mit den Proteinen des Notch-Signalweges Suppressor of hairless [Su(H)] und Notch intracellular domain (N-IC). Zusätzlich werden bei einer Verminderung von Bx42 die Notch Zielgene cut (ct) und enhancer of split m8 [e(Spl)m8] reprimiert (Negeri et al., 2002). In dieser Arbeit wurde die Beteiligung von Bx42 am TGF-ß/Dpp Signalweg untersucht. Es wurde gezeigt, dass Bx42 mit den TGF-ß/Dpp-Signalweg Proteinen Mad und Medea sowohl in vitro als auch in vivo interagiert. Die dabei verwendeten Methoden waren das Hefe-Zwei Hybrid-Sytem und Ni-NTA-Pulldown-Assays. Domänen der Smad Proteine (Mad und Medea), die für die Interaktion mit Bx42 notwendig sind, wurden mit Hilfe von Deletionskonstrukten untersucht. Es konnte gezeigt werden, dass die stark konservierte MH2-Domäne dieser Proteine für die Interaktion notwendig ist. Zudem belegten Versuche die genetische Interaktion zwischen Bx42 und Medea, in denen ein Bx42-RNAi-Phänotyp durch die gleichzeitige Überexpression von Medea gerettet werden konnte. Es ist bekannt, dass das humane Bx42-Homolog Skip sowohl mit den Proteinen Smad2 und 3 des TGF-ß/Activin Signalweg, als auch mit den Onkogenen Sno und Ski interagiert. Skip wirkt hier als Antagonist der Ski/Sno-Wirkung auf den TGF-ß/Activin-Signalweg und fungiert als Koaktivator (Leong et al., 2001). Die Interaktion zwischen Bx42 und der TGF-ß/Activin-Signalweg Komponente dSmad2, sowie mit dem Onkogen dSno konnte in dieser Arbeit auch für Drosophila bewiesen werden. Die Bedeutung dieser Wechselwirkung muss noch in weiteren Arbeiten analysiert werden. Der Einfluss der Bx42-RNAi-Induktion auf die TGF-ß/Dpp Zielgene distal-less (dll), optomotor blind (omb) und spalt (sal) wurde anhand von Reportergen Untersuchungen mit enhancer-trap-Linien und RNA in situ Hybridisierung untersucht. Es konnte gezeigt werden, dass das Ausschalten von Bx42 die Expression dieser Gene in ähnlicher Weise reprimiert, wie eine Elimination des TGF-ß/Dpp-Signals. Diese Ergebnisse unterstützen die Annahme, dass Bx42 in der Lage ist, TGF-ß/Dpp Zielgene durch eine Wechselwirkung mit Mad und Medea zu aktivieren. / The importance of Bx42 in Drosophila development was demonstrated using Bx42-RNA interference. The ubiquitous downregulation of Bx42 generated embryonic lethality, indicating the importance of this protein in early development. The tissue specific induction of Bx42-RNAi resulted in several different phenotypes depending on the driver line and the temperature at which animals were raised. The phenotypes obtained were the key point for the assumption that Bx42 may play a role in the regulation of a number of different cellular signalling pathways. Indeed, within the Notch signalling pathway Bx42 interacts genetically with Suppressor of hairless [Su(H)] and Notch intracellular domain (N-IC). Additionally, the reduction of Bx42 negatively affected the expression of the Notch target Genes cut (ct) and enhancer of split m8 [e(Spl)m8] (Negeri et al., 2002). In this work, the involvement of Bx42 in the Dpp signalling pathway was investigated. It was shown that Bx42 interacts both in vitro and in vivo, as demonstrated by yeast two hybrid protein-protein studies and Ni-NTA pull-down assays, with the TGF-ß/ Dpp components Mad and Medea. Domains of Smads (Mad and Medea) required for Bx42 interaction were examined using deletion constructs of Smads and the importance of the well conserved MH2 domains of Mad and Medea for this interaction was revealed. Moreover, the rescue of the Bx42-RNAi phenotype by the simultaneous overexpression of Medea demonstrated the genetic interaction between Bx42 and Medea. Furthermore, evidences for the interaction of Bx42 with the TGF-ß/Activin pathway component dSmad2 and with the oncogene protein dSno were obtained from interaction assays. The human homologue of Bx42, Skip, also interacts with Smad2/3 or Sno. The meaning of this interaction in Drosophila has yet to be analysed. The influence of Bx42-RNAi induction on the expression of Dpp target genes distal less (dll), optomotor blind (omb) and spalt (sal) was also investigated using enhancer trap lines and RNA in situ hybridisation. In this way it was proven that these genes are suppressed as they are by elimination of Dpp signalling. These results suggest that Bx42 may be able to modulate positively TGF-ß/Dpp signalling through an interaction with the signalling transducer Mad and Medea.
92

Kristallstrukturen der C2B-Domäne von Rabphilin-3A und der PP2C-ähnlichen Phosphatase tPphA von Thermosynechococcus elongatus BP-1 / Crystal structures of the C2B domain of Rabphilin-3A and the PP2C-like phosphatase tPphA of Thermosynechococcus elongatus BP-1

Schlicker, Christine 05 June 2006 (has links)
No description available.
93

Space Charge Modeling at the Integer Resonance for the CERN PS and SPS

Titze, Malte 11 June 2020 (has links)
Die elektromagnetische Wechselwirkung der Teilchen untereinander, wie sie typischerweise in einem Strahl hoher Intensität in den CERN Beschleunigern auftritt, kann in Langzeitsimulationen nicht vernachlässigt werden. Simulationen sind insbesondere notwendig, um diese Beschleuniger zu optimieren und die zugrundeliegende kohärente und inkohärente Dynamik besser zu verstehen. Die Auswirkungen der unumgänglichen Vereinfachungen in der Modellierung der komplizierten Dynamik müssen deshalb untersucht werden. Wir gehen diese Aufgabe an, indem wir sechs verschiedene Strahlführungsmodelle am CERN Proton Synchrotron (PS) und am Super Proton Synchrotron (SPS) untersuchen, die wir dynamisch in der Nähe von horizontalen Integer-Resonanzen operieren. Die sechs Modelle, welche insgesamt in den beiden bewährten Programmpaketen MAD-X und PyOrbit implementiert sind, werden mit den jeweiligen Messungen an beiden Maschinen verglichen, wobei der Schwerpunkt hier auf dem PS liegt. / In long-term tracking simulations of high-intensity beams which are typical in the CERN accelerators, the electromagnetic interaction between the individual particles can not be neglected. Simulations are required to optimize the performance of the accelerators, and to better understand the involved coherent and incoherent dynamics. The impact due to the unavoidable simplifications when modeling the complex dynamics must therefore be studied. We approach this task by examining six different tracking models, applied to the CERN Proton Synchrotron (PS) and the Super Proton Synchrotron (SPS), both of which were dynamically operated near horizontal integer resonances. The six models, which are overall implemented in the well-known program packages MAD-X and PyOrbit, are compared to beam-based measurements on both machines, with the PS as the main emphasis.
94

Etudes in situ et ex situ par rayonnement synchrotron de la croissance d'îlots de Ge sur substrats de Si(001) nominaux et préstructurés.

Richard, Marie-Ingrid 14 December 2007 (has links) (PDF)
Les travaux présentés dans ce manuscrit sont consacrés à l'étude structurale (taille, déformation, défauts, composition) d'îlots de Ge sur substrats de Si(001) nominaux et pré-structurés durant ou après croissance par épitaxie par jet moléculaire, en utilisant la diffraction (anomale) des rayons X en incidence rasante àl'Installation Européenne de Rayonnement Synchrotron (ESRF). <br />Les échantillons ont été caractérisés soit ex situ après croissance sur la ligne de lumière ID01, soit in situ durant leur croissance par EJM grâce au dispositif dédié sur la ligne BM32. <br />Les effets dynamiques associés à l'utilisation de l'incidence rasante ont été étudiés sur la base de simulations des champs de déformations dans les nanostructures de Ge. Les résultats ont montré l'influence majeure de l'angle d'incidence sur l'intensité diffusée par les nano-objets de taille de l'ordre de la centaine de nanomètres. Une nouvelle technique de rayons X a été développée pour détecter leur présence et étudier la structure de leur coeur en se concentrant sur l'intensité diffusée par les défauts autour de réflexions interdites. Pour comprendre les dynamiques de croissance, la forme, la taille, le mode de croissance, la composition et la présence éventuelle de défauts et/ou d'ordre atomique à l'intérieur des nanostructures ont été caractérisés en fonction du dépôt, de sa température, de la vitesse de croissance et du recuit. L'évolution des déformations, la transition élastique-plastique, l'interdiffusion et leur relation avec les différentes morphologies des îlots ont été étudiés grâce à l'utilisation de techniques in situ de rayons X. L'étude a mis en évidence l'apparition précoce des dislocations dans les îlots durant la croissance lente de Ge sur Si(001) et la formation d'un nouveau type de superdomes qui résulte de la coalescence d'îlots. <br />Enfin, les croissances sur surfaces Si(001) nominales et pré-structurées ont étécomparées. La structuration a été obtenue soit par lithographie électronique soit par collage moléculaire et attaque chimique. Ces études ont permis de montrer qu'en modulant la surface, il est possible de changer l'état de relaxation et l'énergie élastique totale des îlots sans modifier leur composition moyenne en Ge. Ces résultats ont aussi révélés que le processus d'interdiffusion n'est pas induit par la contrainte mais plutôt par les phénomènes de diffusion de surfaces.
95

Wire Explosion via Electromagnetic Induction

van Herel, Ryan Marinus Johannes Wilhelmus Maria January 2011 (has links)
This research is aimed at exploding a wire via electromagnetic induction, with a preference for obtaining restrike of the exploding wire in a ring shape or otherwise. Literature on both exploding wire and electromagnetic induction are introduced together. A mathematical framework to describe the wire explosion by induction is formulated from first principles using the idea of magnetic flux linkages. The environment in which the experiments took place is described, with reference to matters of laboratory safety and also measurement of transient electrical current and voltage in the wire explosion by induction. The results describe the approaches taken to explode a wire by induction to obtain a plasma conductor. Voltage and current data are displayed and described. Throughout this work, there are long-exposure digital photographic images of the experiments taking place. These contribute to determining the outcome of experiments, and support the conclusions. Wires were exploded by induction in an air-cored mutually coupled coils system, and restrike of those wires was achieved. Electrical characteristics of wire explosion by electromagnetic induction are displayed and discussed based on what is known about straight exploding wires. Future works involving creation of plasma rings, electromagnetic thrust and exploding wires in vacuum are discussed.
96

Stínová kinematografie - Mytologie australského gotického filmu 70.let / Shadow Cinema - TheMythology of Australian gothic films in 1970s

Kotrlová, Jitka January 2015 (has links)
8 Univerzita Karlova v Praze Filozofická fakulta Katedra filmových studií Diplomová práce Jitka Kotrlová Stínová kinematografie: mytologie australského gotického filmu 70. let Shadow Cinematography: Mythology of the Australian Gothic Film of the 1970's Praha 2015 Vedoucí práce: PhDr. Petra Hanáková, Ph.D Abstract: The thesis focuses on the mythological aspects of films of the so-called Australia gothic in 1970's. In a detailed form of thematic analysis it discovers three fundamental myths within the gothic cycle which then examines the semiotic method of Roland Barthes. The first part is dedicated to the specific situation of the film industry and describes the principles of film funding. The second part is focused on the concept of national cinematography in relation to Australia. The third part is dedicated to the gothic imagination and definition of Australian gothic within the contemporary discourse. The fourth part focuses on the term "mythology". The main part of the thesis presents the three myths emerging from the cycle of Australian gothic films. The first one is the myth of the feeling of isolation that focuses on the meaning of an isolated man in the inland and on the alternation of this myth in the form of a person isolated in the society. On the examples of the films Walkabout (Nicholas Roeg,...
97

Člověk v šíleném dění světa (Pojetí člověka u raného Deleuze) / A man in becoming-mad of the world (The conception of a man by early Deleuze)

Prášek, Petr January 2013 (has links)
The philosophy of early Deleuze is the main subject of this dissertation. Concretely, it will be treated with regard to distinctive and singular individuation of a man: this essay tries to present his relationship to the ultimate horizon of Being in Deleuze's work. The first chapter constitutes a starting point which can be determined in criticism of the image of thought, closely related with Deleuze's transcendental empiricism. The second chapter is devoted to its culmination, to the metaphysical description of the virtual field of Ideas, of transcendental conditions of our experience. The next chapter shows how Ideas condition, that Ideas actualise themselves insofar as something develops itself within its intensive field of individuation. The fourth chapter takes us back to our starting point: it concerns a phenomenon, this time sufficiently explained, and we are again obliged to confront us with the image of thought which covers this explanation. This is the reason why our interpretation has to continue. The description of distinctive and singular individuation of a man wants to explain the way by which the image of thought, based on common sense, is established. Even though our experience is constructed on this image, there are still some "small islands" of difference, places where the virtual...
98

A troubled past: reconfiguring postwar suburban American identity in revolutionary road, 1961 and mad men, 2007-2012

Unknown Date (has links)
This thesis takes a cultural studies approach to representations of post-war U.S. suburbia in Richard Yates’ 1961 novel Revolutionary Road, as well as in the contemporary AMC television series Mad Men. These texts explore the postwar time period, which holds a persistently prominent and idealized space in the collective cultural imagination of America, despite the fact that it was a period troubled by isolationism, containment culture, rampant consumerism, and extreme pressure to conform to social roles. This project disrupts the romantic narrative of postwar America by focusing on the latent anxiety within the suburban landscape—by interrogating the performative nature of the planned communities of the 1950s and 1960s and exposing the tensions that were borne out of the rise of domesticity and consumerism. This project explores the descent into a society obsessed with consumerism and conformity, and seeks to interrogate the culture’s false nostalgia for the time period. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2013.
99

Des décisions publiques « médiatiques » ? : sociologie de l’emprise du journalisme sur les politiques de sécurité sanitaire des aliments / Policy Decisions Shaped by the Media? : media-oriented Food Safety Policies : a Sociological Approach

Nollet, Jérémie 07 December 2010 (has links)
Les médias font-ils les décisions publiques ? Cette conception d’un pouvoir du journalisme sur les politiques publiques est répandue parmi les « décideurs ». Elle est aussi présupposée par les théories de l’agenda et de la construction sociale des problèmes. La réalité du phénomène est cependant plus complexe : ce pouvoir n’est ni uniforme ni unidirectionnel. Il repose sur la contribution active et variable des agents politiques et administratifs qui produisent ces décisions. La question s’en trouve alors reformulée : dans quelle mesure la production des décisions publiques peut-elle se faire en fonction du champ journalistique ? Pour y répondre, la thèse propose une sociologie des logiques spécifiques de prise en compte de la médiatisation dans les activités décisionnelles au sein des champs politique (dans les cabinets ministériels et au Parlement) et administratif (dans les administrations centrales des ministères). L’élaboration de ce cadre théorique, au croisement de la sociologie du journalisme et de celle de l’action publique, s’appuie sur l’analyse de la gestion politico-administrative de la maladie de la « vache folle » en France dans les années 1990. Il s’agit de restituer l’importance que les responsables de l’exécutif (en particulier les ministres de l’Agriculture, de la Consommation, de la Santé, mais aussi le Premier ministre et le président de la République), les parlementaires et les hauts fonctionnaires ont pu accorder aux enjeux médiatiques jusque dans leurs pratiques décisionnelles. Il apparaît ainsi que les décisions les plus « médiatiques » sont le produit de la prise en charge des dossiers les plus emblématiques selon les logiques d’action des agents les plus dépendants des enjeux de légitimation dans le champ journalistique : les principaux ministres et leurs conseillers / Are public policies made by the media? This would-be influence of journalists over public decisions is common place among “decision-makers”. It is also assumed by Agenda-setting as well as social problems theorists. Yet, the real nature of the phenomenon is more complex: it follows different paths along several directions. It rests on the active and variable engagement of the politicians and high civil servants who produce decisions. Thus, the question needs to be rephrased: to what extent does the production of public decisions depend on the journalistic field? In order to elucidate this question, this doctoral thesis offers a sociological analysis of the specific logics which lead decision-makers (i.e. ministers’ personal staff, and representatives aswell as high civil servants,) to pay attention to media coverage in decision-making processes. The elaboration of this theoretical framework, at the crossroads of the sociologies of journalism and public action, is based on ananalysis of the handling of the mad cow disease by French officials during the 1990s. The ambition is to account for the very attention the holders of the executive power (namely, the Ministers of Agriculture, Consumption,Health, but also the Prime Minister and the President), the members of Parliament and high civil servants paid to media-related challenges within the practice of decision-making. Thus, it appears that the most “media dependent”decisions are the result of the handling of the most symbolic issues according to the logics of action of the most dependent agents on legitimization stakes in the journalistic field: the principal ministers and their advisers
100

”Mitt barns medicin” : En kvalitativ studie om föräldrars upplevelser av deras barns behandling med Modifierad Atkins Diet och ketogenkost. / ”My Child´s Medicine” : A qualitative study on how parents experience their children`s treatment with Modified Atkins Diet or Ketogenic Diet.

Holmström, Annika, Mårtensson, Lotta January 2012 (has links)
BAKGRUND Modifierad Atkins Diet (MAD) och ketogenkost är kostbehandlingar som ordineras till barn med svårbehandlad epilepsi. Andra patientgrupper som behandlas med dessa dieter är patienter med glukostransportprotein typ 1-brist. Kostbehandlingarna är kolhydratfattiga och fettrika. I Sverige finns fyra sjukhus som arbetar med MAD och ketogenkost. I dagsläget saknas studier som beskriver hur behandlingarna upplevs av berörda familjer. SYFTE Syftet med studien var att utforska hur föräldrar till barn som behandlas med MAD eller ketogenkost upplever kostbehandlingen. METOD Kvalitativa intervjuer baserade på en halvstrukturerad frågeguide har genomförts. Fem familjer från olika delar av landet deltog i studien. Intervjuerna spelades in med mp3-spelare för att sedan transkriberas ordagrant. Samtalen analyserades genom kvalitativ innehållsanalys. RESULTAT Föräldrarna berättade om en rädsla och oro inför behandlingsstarten och att introduktionsperioden som familjerna erbjöds inför kostbehandlingen visade sig vara mycket viktig för kommande behandlingsprocess. Föräldrarna upplevde det svårt att tillaga en varierad kost och att det var viktigt med adekvata hjälpmedel och regelbunden vårdkontakt för att kunna tillämpa kostbehandlingen i vardagslivet. Deras behov av stöd förändrades under behandlingsprocessen. Genomgående var att informanterna upplevde att de sociala aktiviteterna anpassades efter kostbehandlingen. Föräldrarna upplevde det som viktigt att ha kontakt med andra familjer i liknade situation. Trots att föräldrarna upplevde flera olika praktiska och sociala problem ansåg de ändå att det positiva, som var kopplat till behandlingens resultat övervägde. En förälder uttryckte sig med orden ”Vi fick tillbaka vårt barn”- vilket återspeglar många föräldrars åsikt om behandlingen. SLUTSATS MAD och ketogenkost kräver mycket tid och kunskap för berörda familjer och påverkar deras vardag både praktiska och socialt. Med stöd från vård, barnomsorg, familj och vänner upplevde föräldrarna att det var lättare att upprätthålla behandlingen. Det finns också ett behov av att få prata med andra föräldrar och familjer som är liknande situationer. / BACKGROUND Modified Atkins Diet (MAD) and Ketogenic Diet are treatments prescribed to children suffering from refractory epilepsy. Patients with glucose transporter protein type 1 deficiency are also commonly treated with these diets, which are low in carbohydrates and high in fat. In Sweden, there are four hospitals implementing these treatments, but there is currently not sufficient information on how they are affecting the families. OBJECTIVE The purpose of this study was to explore how parents of children treated with MAD or Ketogenic Diet experience the treatment. METHOD Qualitative interviews based on a semi-structured topic guide was conducted. Five families from different parts of Sweden participated in this study. The interviews were recorded with an mp3 device and transcribed verbatim. Qualitative content analysis was used for data analysis. RESULT The parents disclosed anxiety before the start of the treatment and they acknowledged that the first week of introduction, which they, were offered before the start, proved to be essential for the rest of the treatment process. The families found it difficult to cook a balanced meal according to the dietary requriements, and also that it was important to have adequate resources and routine contact with health services to be able to apply the treatment to daily life. Their need for support changed during the treatment process. The informants believed their social activities were accommodated due to treatment. The parents felt the need to be in contact with other families in a similar situation. One parent expressed him-/herself with the words “We got our child back”, which reflects many parents view, regarding the treatment. CONCLUSION MAD and Ketogenic Diet require a lot of time and knowledge and affect practical and social aspects in daily living. With the support of health care, child care, family and friends, the parents felt it was easier to maintain treatment. The informants also shed light on the necessity of being in contact with other parents and families in similar situations.

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