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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.
151

Regionální mocnosti a bezpečnostní dynamika: Vliv Ruska, Turecka a Íránu na bezpečnost jižního Kavkazu / Regional Powers and Security Dynamics: How do Russia, Turkey and Iran shape security in the South Caucasus?

Matjasch, Alexandra January 2021 (has links)
The aim of the present paper is to answer the question on how do regional powers shape the security environment within their regional subcomplex? The research interest is conditioned by the rise of powers that represent strong actors, especially in regional affairs, and which certainly influence dynamics within their region. It has been assumed that the manifestation of power at the regional level can also be transferred, to the global level leading to an elevated position of these actors in global affairs, allowing equally for the existing Western-led order to be challenged. These assumptions have been applied and tested on the example of the regional powers Russia, Turkey and Iran and their respective influence on the security dynamics in the South Caucasus as their historically common shared neighbourhood. In order to disentangle the complicated web of relationships and influential factors, the descriptive framework of the Theory of Regional Security Complexes as suggested by Barry Buzan has been outlined and applied. Based on these theoretical observations the attention has been further turned towards the empirical testing of the hypothesis which states that Russia, Turkey and Iran have exercised influence during the second Nagorno-Karabakh War 2020 that occurred between Armenia and Azerbaijan...
152

Evolučně zachovalé mechanismy regulace genové exprese jadernými receptory. / Evolutionarily conserved mechanisms of gene expression regulation by nuclear receptors.

Chughtai, Ahmed Ali January 2019 (has links)
Transcriptional regulation of gene expression in eukaryotes has evolved over millions of years. The regulatory pathways of nuclear receptors represent an evolutionarily ancient, but conserved mechanism with associated accessory proteins, many of them forming a functional nexus known as the Mediator complex involved in transcription. Despite the versatility of the pathway, e.g. through the adoption of new regulatory functions in phylogenetically more recent Metazoa, we hypothesise that the intrinsic potential of the NR-Mediator axis to directly translate a stimulus to a biological response is conserved across species, and additional regulation could also be achieved through secondary functions of its essential members. To support the hypothesis, we assessed the ligand-binding capability of retinoic X receptor in Trichoplax adhaerens and provided evidence to support the concept that this capability was already present at the base of metazoan evolution. With regards to the potential secondary functions, we took inspiration from previous research and identified the Mediator subunit 28 (MED28) as the only known member having documented nuclear and cytoplasmic dual roles, and thus possessing the potential to transmit signals from the cellular structural states to the nucleus. Due to the lack of...
153

Genomická architektura a molekulární mechanismy hybridní sterility myši. / Genomic architecture and molecular mechanisms of hybrid sterility in mice.

Vališková, Barbora January 2021 (has links)
Hybrid sterility is one of the reproductive isolation mechanisms restricting gene flow between the related species and leading to speciation. PR domain containing 9 (Prdm9), the only known vertebrate hybrid sterility gene, determines the sites of programmed DNA double-strand breaks (DSBs) and thus specifies hotspots of meiotic recombination but in hybrids between two mouse subspecies causes failure of meiotic chromosome synapsis and hybrid male sterility. In the present study on sterile hybrids, the five smallest autosomes were more prone to asynapsis. To manipulate with the synapsis rate, random stretches of consubspecific homology were inserted into several autosomal pairs. Twenty seven or more megabases of consubspecific sequence fully restore synapsis in a given autosome. Further, at least two symetric DN double-strand breaks per chromosome were necessary for successful synapsis. Moreover, F1 hybrids had sperm when synapsis was rescued in at least three of four segregating chromosomes. To verify the assumption of a lack of symmetric DSBs in meiotic chromosomes of sterile males the chemotherapeutic drug cisplatin was used to induce exogenous DNA DSBs. Cells treated with 5 mg/kg and 10 mg/kg of cisplatin showed increased number of DSBs monitored by immunostaining of RPA and DMC1 sites and...
154

Untersuchungen zum Einfluss von neurotoxinhaltigen Kulturüberständen der Clostridium botulinum Toxovare A bis G auf eukaryote Degradierungssysteme am Modellorganismus Tetrahymena pyriformis GL

Ständer, Norman Martin 12 December 2006 (has links)
In der vorliegenden Arbeit sollte die Eignung von T. pyriformis GL für den Nachweis von Botulinumneurotoxinen als biologische Alternative zum Maus-Bioassay untersucht werden. Dazu wurden funktionelle Tests für die Quantifizierung der mutmaßlich SNARE-abhängigen Prozesse Phagozytose und Exozytose entwickelt. Die Botulinumneurotoxine wurden durch Kultivierung der C. botulinum-Toxovare A bis G in einem Caseinpepton-Glukose-Hefeextrakt-Medium mit und ohne Zusatz von Trypsin herge-stellt. Die Neurotoxinkonzentrationen wurden mit Hilfe des Maus-Bioassays bestimmt. Für den Phagozytosetest wurde E. coli K12 als Beutekeim gewählt. Es konnte gezeigt werden, dass die KbE/ml von E. coli K12 allein durch die Phagozytoseaktivität von T. pyriformis reduziert wurde. Für den Exozytosetest wurde die saure Phosphatase als Leitenzym gewählt. Die neurotoxinhaltigen Kulturüberstände wurden mit Neurotoxinendkonzentrationen von 1,50E+02 MLD/ml (Maus letale Dosis/ml) bei den trypsinisierten und nicht trypsinisierten Ansätzen der Toxovare A bis D, F und G bzw. von 1,50E+00 MLD/ml bei dem trypsinisierten Ansatz des Toxovars E in den entwickelten Tests eingesetzt und auf ihren Einfluss untersucht. Die eingesetzten Neurotoxinkonzentrationen erwiesen sich als nicht ausreichend. Zudem wurde eine erhebliche Anfälligkeit der Phagozytose- und Exozytoseleistung von T. pyriformis gegen die Proteinkonzentrationen der eingesetzten Kulturüberstände nachgewiesen. Aufgrund dessen ist die Eignung von T. pyriformis im Rahmen der entwickelten Tests für den Nachweis von Botulinumneurotoxinen aus Proben wie biologischen Substraten oder mit ähnlichen, komplexen Matrizes nicht gegeben.
155

Wind turbines over a hilly terrain: performance and wake evolution / Vindturbiner över en kuperad terräng: prestanda och vakutbredning

Hyvärinen, Ann January 2018 (has links)
The aim of this licentiate thesis is to investigate wind-turbines placed in a complex-terrain environment. This is done by studying the flow around small-scale wind-turbine models placed over a landscape model with hills, and by comparing the results with corresponding data obtained over a flat terrain model. The studied flow features include the wind-turbine wake development and the turbine performance under different conditions, the effects from wake interactions, the influence of the ambient turbulence levels and the influence from a complex topography. Wind-tunnel measurements have been performed using particle image velocimetry and hot-wire anemometry to measure the velocity field. Additionally, numerical simulations, based on RANS modelling and actuator-disc techniques, have been made to support the experimental data and to gain further knowledge about the investigated flow cases. The results reveal that the hills promote a downward wake deflection behind the turbines and enhance the wind-turbine wake diffusion. As a consequence of this, and with the flow acceleration introduced by the hills, an improved power performance is seen for turbines exposed to wake-interference effects. A correlation is observed between the turbulence levels present in the flow, and the magnitude to which the hill-induced flow gradients influence the wake: Stronger wake deflections due to the hills are seen when the wind-turbine wake is more diffused. This is for instance the case when the wake of two tandem turbines is studied, or when higher ambient turbulence levels are present in the wind tunnel. A good qualitative agreement is seen when comparing the experimental and numerical results. The simulation results further indicate that the hills give rise to modulations of the wind-turbine wake. It is shown that these modulations can be reasonably captured by means of wake-superposition techniques, given that a wake model with sufficient accuracy is chosen. / Syftet med denna licentiatavhandling är att öka förståelsen om hur vindturbiner påverkas av en omgivande komplex terräng. Huvudsakligen betraktas luftströmningen kring småskaliga vindturbinsmodeller som placerats över en landskapsmodell med kullar. I tillägg görs jämförelser med resultat som erhållits då vindtubinerna placerats över en platt landskapsmodell. De studerade strömningsaspekterna inkluderar vindturbinernas vakutveckling och prestanda under olika förhållanden, inverkan från vakinteraktioner, inflytande från omgivande turbulensnivåer och inverkan från en komplex topografi. Vindtunnelmätningar har utf ̈orts där PIV och varmtrådsanemometri användes för att uppmäta hastighetsfält. I tillägg har numeriska simuleringar utförts baserade på RANS-modellering, där turbinens rotor beskrevs av en porös skiva. Simuleringarna gjordes som komplement till de experimentella mätresultaten för att få en ökad förståelse om de undersökta strömningsfallen. Resultaten från mätningarna och simuleringarna med kullar visar att terrängvariationerna främjar en nedåtgående vakförskjutning bakom turbinerna och ökar vindturbinernas vakdiffusion. Detta, i kombination med luftens acceleration över kullarna, resulterar i att en högre effektprestanda utvinns från en vindturbin vars inströmmande luftflöde störs av vaken från en framförliggande turbin. Vidare observeras kraftigare nedågående vakförskjutningar på grund av det kullriga landskapet då vindturbinsvakarna är mer diffunderade. Detta är exempelvis fallet då vaken bakom två turbiner placerade i en tandemkonfiguration studeras, eller när höga omgivande turbulensnivåer uppmäts i vindtunneln. En bra kvalitativ överensstämmelse kan ses mellan de experimentella och numeriska resultat som uppnås. Resultaten från simuleringarna indikerar dessutom att landskapet med kullar ger upphov till moduleringar av vindturbinens vak. Det visas att dessa moduleringar kan beskrivas någorlunda väl med hjälp av vaksuperpositionsmetoder, givet att en vakmodell med tillräckligt hög noggrannhet väljs. / <p>QC 20180122</p>
156

Co lze postavit v největším vnitrobloku města Brna? / What can be built in the largest city block in Brno?

Tůmová, Helena January 2012 (has links)
The chosen locality of the diploma project is situated in the centre of Brno, on the edge of the historical part of the city. It borders on the main green belt and the biggest city park Lužánky. The analyzed block is unique because of its oversize and its composition. However, objects in a courtyard contrasts to the representative town houses on the perimeter. They appear very unordered; it is not possible to walk through this part of the city. The secondary functions, like storages and on-ground parking, are located there. The greenness is not maintained. The objects split the courtyard into not specified and separated spaces, which are even complicated by sloping topography. Nowadays the block makes a barrier in the city structure. The main values of the courtyard are its location, size and calm atmosphere. The potential of the site is possible to use for a proposal of a high-quality dwelling complex. The proposed structure is designed on a linear base, it correspondents to the shape of the chosen site. It creates also public and semiprivate open spaces, which can serve for the new inhabitants. The simple look of the new structure seems to be in harmony with the existing buildings. Even more, the open character of the proposal cultivates the entire block and improves the city structure.
157

Škola, základ života - Soubor školských staveb v Ostravě na Černé louce / School, the Foundation of Life – a Complex of Educational Buildings in Ostrava, Cerna louka

Knežníková, Zuzana January 2014 (has links)
The main idea of the project is the ambition to create an ageless school design, which is able to react flexibly to the constantly evolving educational system and changing space requirements. Philosophy is based on the principle of "open school". School as an important public building has a great potential to act as a catalyst within the neighbourhood. On one hand, it is open to the public by the means of shared facilities (library, gymnasium, multipurpose hall, art classrooms, language labs…). But on the other hand, openness is also important within the school itself. School can be understood as a small community. And because every community needs a public space as a platform for common activities, the school may have its own in the form of a central atrium. It acts as a "piazza", where numerous diverse activities are allowed to happen. Proposal for a school organization is based on the ability of social integration, which is gradually formulated throughout the childhood.
158

Škola, základ života - Soubor školských staveb v Ostravě na Černé louce / School, the Foundation of Life – a Complex of Educational Buildings in Ostrava, Cerna louka

Trenz, Miloš January 2014 (has links)
The goal of this project si to design school building in Černá louka in Ostrava city. Besides aim to achieve architectural and typological harmony it tries to clarify a collision of disparate urban structures. Its trying to cultivate and develop approved zoning plan.
159

Škola, základ života - Soubor školských staveb v Ostravě na Černé louce / School, the Foundation of Life – a Complex of Educational Buildings in Ostrava, Cerna louka

Dufková, Kateřina January 2014 (has links)
The topic of my diploma thesis is a design of a new complex of schools in Ostrava. The place of this project is located close to a historical centre next an exhibition grounds Černá louka. The main idea is a design of single houses which are created to a closed block with an inner area with large garten. The children from secondary school will during their environment lessons plant various plants and students from the high school will get to know in their biology lessons these plants. The complex is divided by functions to five different houses: kindergarten, primary school with secondary shool, grammer school, kitchen with school canteen and sport complex.
160

The History of the Dirichlet Problem for Laplace’s Equation

Alskog, Måns January 2023 (has links)
This thesis aims to provide an introduction to the field of potential theory at an undergraduate level, by studying an important mathematical problem in the field, namely the Dirichlet problem. By examining the historical development of different methods for solving the problem in increasingly general contexts, and the mathematical concepts which were established to support these methods, the aim is to provide an overview of various basic techniques in the field of potential theory, as well as a summary of the fundamental results concerning the Dirichlet problem in Euclidean space. / Målet med detta arbete är att vara en introduktion på kandidatnivå till ämnesfältet potentialteori, genom att studera ett viktigt matematiskt problem inom potentialteori, Dirichletproblemet. Genom att undersöka den historiska utvecklingen av olika lösningsmetoder för problemet i mer och mer allmänna sammanhang, i kombination med de matematiska koncepten som utvecklades för att användas i dessa lösningsmetoder, ges en översikt av olika grundläggande tekniker inom potentialteori, samt en sammanfattaning av de olika matematiska resultaten som har att göra med Dirichletproblemet i det Euklidiska rummet.

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