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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.
101

Development of Partially Supervised Kernel-based Proximity Clustering Frameworks and Their Applications

Graves, Daniel Unknown Date
No description available.
102

Die Exportplattform als Instrument der ausländischen Marktversorgung / The export platform as an instrument for foreign market supply

Cirannek, Vanessa January 2013 (has links)
Zur Versorgung ausländischer Märkte bedienen sich Unternehmen unterschiedlicher Versorgungsformen. Die proximity-concentration trade-off-Literatur betrachtet die Wahl zwischen Export und Auslandsproduktion und erklärt die Entstehung von internationalem Handel und horizontalen ausländischen Direktinvestitionen. Das Standardmodell von Brainard (1993) integriert die Auslandsproduktion als alternative Versorgungsform zum Handel in ein allgemeines Gleichgewichtsmodell mit zwei Ländern, monopolistischer Konkurrenz, steigenden Skalenerträgen und Transportkosten. Im Gleichgewicht versorgen Unternehmen ausländische Märkte entweder durch Exporte oder eine Auslandsproduktion. Die real zu beobachtende Ko-Existenz von internationalem Handel und ausländischen Direktinvestitionen auf der Unternehmensebene kann mit diesem Modell nicht erklärt werden. Im Rahmen dieser Arbeit wird die Exportplattform (EP) als mögliche Antwort auf dieses Phänomen herangezogen. Eine Exportplattform ist eine Auslandsproduktion, durch die nicht nur der lokale Auslandsmarkt, sondern auch Drittländer versorgt werden. Im modelltheoretischen Teil dieser Arbeit wird ein partialanalytisches EP-Modell formuliert, dass auf Brainard (1993) aufbaut. Dabei wird ihr Modell um eine Mehr-Länder-Welt mit heterogener Verteilungsstruktur erweitert und die Versorgungsalternative der EP-Exporte nach dem Beispiel von Neary (2002) integriert. Durch die analytische Lösung des partiellen Gleichgewichts lässt sich die substitutive Beziehung zwischen Heimatexporten, Auslandsproduktion und EP-Exporten aufzeigen. Ferner kann die Wirkung der Versorgungskosten auf die Versorgungswahl analysiert werden. Dabei wird neben der analytischen Modellbeschreibung besonders auf die Gleichgewichtsbestimmung und die Existenz der Gleichgewichte eingegangen. Aufbauend auf den analytisch abzuleitenden Hypothesen wird das EP-Modell ferner einem empirischen Signifikanztest unterzogen. Unter Anwendung von nicht-linearen Regressionsverfahren wird die Wahl zwischen EP-Exporten und Auslandsproduktion, zwischen EP- und Heimatexporten sowie zwischen EP-Exporten und der EP-Produktion separat geschätzt. Hierfür wird auf Daten der Automobilindustrie zurückgegriffen, welche die regionalen PKW-Produktions- und -Absatzdaten sämtlicher Automobilhersteller in Osteuropa, Asien und Ozeanien umfassen. / The proximity-concentration trade-off literature explains the choice between international trade and foreign direct investments. In this book, the co-existence of international trade and foreign direct investments is explained by analyzing the choice of export platforms. First, a partial equilibrium model with monopolistic competition, increasing economies of scale, trade costs and fixed costs is developed and enhanced with a heterogeneous, spatial distribution of regions. Second, hypothesis are tested with international trade and production data from the automotive industry.
103

Proximity Ligation and Barcoding Assays : Tools for analysis of proteins and protein complexes

Wu, Di January 2014 (has links)
Proteins are fundamental structural, enzymatic and regulatory components of cells. Analysis of proteins, such as by measuring their concentrations, characterizing their modifications, and detecting their interactions, provides insights in how biological systems work physiologically or pathologically at the molecular level. To perform such analysis, molecular tools with good sensitivity, specificity, high multiplexing and throughput capacity are needed. In this thesis, four different assays were developed and applied to detect and profile proteins and protein complexes in human body fluids, and in cells or tissues. These assays are based on targeting proteins or protein complexes by oligonucleotide-conjugated antibodies, and subsequent proximity dependent enzymatic reactions involving the attached DNA reporter sequences. In paper I, a solid-phase proximity ligation assay (SP-PLA) was applied to detect synthetic and endogenous amyloid beta protofibrils. The SP-PLA provided better sensitivity and increased dynamic range than a traditional enzyme-linked immunosorbent assay (ELISA). In paper II, in situ PLA was applied to investigate the correlation between MARK2-dependent phosphorylation of tau and Alzheimer’s disease. Greater numbers of MARK2-tau interactions and of phosphorylated tau proteins were observed in brain tissues from Alzheimer’s patients than in healthy controls. In paper III, a multiplex SP-PLA was applied to identify protein biomarker candidates in amyotrophic lateral sclerosis (ALS) disease and in the analgesic mechanism of spinal cord stimulation (SCS). Among 47 proteins in human cerebrospinal fluid (CSF) samples, four were found at significantly lower concentrations (p-values < 0.001) in the samples from ALS patients compared to those from healthy controls (follistatin, IL-1α, IL-1β, and KLK5). No significant changes of the analyzed proteins were found in the CSF samples of neuropathic pain patients in   the stimulated vs. non-stimulated condition using SCS. In paper IV, a new technology termed the proximity barcoding assay (PBA) was developed to profile individual protein complexes. The performance of PBA was demonstrated on artificially assembled streptavidin-biotin oligonucleotide complexes. PBA was also proven to be capable of profiling transcriptional pre-initiation complexes from nuclear extract of a hepatic cell line.
104

Development of microfluidic device for high content analysis of circulating tumor cells / Développement d'un système microfluidique pour l'analyse haut-contenu de cellules tumorales circulantes

Tulukcuoglu Güneri, Ezgi 20 October 2016 (has links)
Le cancer est l'une des principales causes de décès dans le monde. D'après la société américaine contre le cancer; en 2015, un quart des décès aux Etats-Unis est du au cancer du poumon avant même les maladies cardiaques. Cette situation nous incite et bien d'autres scientifiques dans le monde à développer des moyens plus efficaces de traitement, le diagnostic et le dépistage de la maladie. Parce que près de 90% des décès par cancer sont dus à des métastases, de nombreuses études se sont concentrées sur le mécanisme de métastases et sur son impact clinique. Les cellules tumorales circulantes (CTC) sont les cellules s’échappent de tumeurs primaires ou métastatiques pour rejoindre le flux sanguin périphérique, ces cellules sont un élément de transition dans le processus métastatique et portent ainsi des informations cruciales sur ce mécanisme encore mal compris. Les CTCs ont déjà montré leur potentiel comme biomarqueur de pronostic de la progression de la maladie et de l'indicateur de l'efficacité du traitement en fonction l’augmentation ou de la diminution de leur nombre. Leur caractérisation moléculaire peut également donner des informations vis à vis de cibles thérapeutiques possibles et des mécanismes de progression de la maladie ou de la résistance aux médicaments. Leur comptage au cours du traitement combiné avec leur caractérisation moléculaire devrait améliorer la prise en charge des patients dans le cadre de la médecine personnalisée. Cependant CTCs sont extrêmement rares, 1 à 10 cellules / ml de sang parmi les 106 globules blancs et 109 globules rouges, leur capture à partir du sang reste donc un challenge analytique. Dans les dernières décennies, Une grande variété de techniques d'enrichissement et de capture a été mise au point et l'approche microfluidique est l'une des méthodes efficaces, flexibles et à haut débit. Au sein de notre équipe, un dispositif microfluidique (système Ephesia) puissant pour la capture et l'analyse des cellules tumorales circulantes a déjà été mis au point précédemment. Le principe de capture est basé sur l'auto-assemblage de billes magnétiques greffées par des anticorps, grâce aux quelles les cellules sont enrichies via l’interaction Ab- l'antigène de surface EpCAM que l'on trouve communément dans les cellules cancéreuses d'origine épithéliale. Ce système a déjà été validé avec des lignées cellulaires et des échantillons de patients. Cependant, le système n'a pas permis l'isolement / détection des sous-populations de CTCs ou d'effectuer une caractérisation moléculaire très poussée. Par conséquent, mon projet de thèse vise à améliorer encore les capacités du système sur les deux principaux aspects: le ciblage sous-populations de CTC et à l'étude des interactions des protéines à la surface des CTCs dans le Système Ephesia... / Metastasis is the advanced stage of cancer progression and is the cause of 90% of deaths in cancer disease. During metastatic cascade, it is suggested that the successful metastatic initiation depends on the survival of circulating tumor cells (CTCs). CTCs are the cells that shed from the primary or secondary tumor sites into the blood circulation. it is now widely recognized as potential biomarker for companion diagnostics in which high number of CTCs in blood can indicate association with poor survival or high risk of disease progression. Besides, following the number of CTCs during the course of treatment can help to adapt the selected therapy and predict the treatment efficacy. On the other hand molecular characterization can provide patient stratification and identifying the therapeutic targets. However they are extremely rare in the bloodstream, estimated between 1-10 CTC among 6×106 leukocytes, 2×108 platelets and 4×109 erythrocytes per one mL of blood which makes their isolation very challenging. A very attractive way of isolation of CTCs is to integrate microfluidics. Microfluidics offers great advantages such as low volume of reagent consumption and short analysis times with automation as well as isolation and detection analysis can be integrated resulting in highly efficient biomedical devices for diagnostics. As parallel to state of the art, a powerful microfluidic device for circulating tumor cells capture and analysis had already been developed previously in our laboratory. The principle of capture is based on self-assembly of antibody-coated (EpCAM) magnetic beads in which the cells are enriched by EpCAM surface antigen which is found commonly in epithelial origin cancer cells. This system was already validated with cell lines and patients samples. However, the system did not allow isolation/detection of subpopulations of CTCs or performing high content molecular characterization. Therefore, my PhD project aimed at further improving the capabilities of the system on the main two aspects: targeting subpopulations of CTC and studying of protein interactions of CTCs in Ephesia System...
105

Skin efekt ve vysokootáčkových elektrických strojích. / Skin effect in high-speed electrical machines.

Klíma, Petr January 2019 (has links)
This master thesis deals with the suppression of the skin and proximity effects in high-speed machines. The first part summarizes the general knowledge of high-speed machines. The second part is devoted to the principle and possible suppression of consequences caused by skin and proximity effects. The third part shows the simulation results of models of a synchronous machine with permanent magnets. The results of these simulations reveal the consequences of skin and proximity effects. In addition, design measures are proposed to limit these and other undesirable phenomena to achieve the highest possible efficiency.
106

Optimalizace tvaru paralelních proudovodných drah odpojovače / DISCONNECTOR PARALLEL CURRENT PATHS OPTIMIZATION

Görig, Tomáš January 2015 (has links)
The objective of this master´s thesis is diagnostic the actual disconnector current path that is unevenly stressed by nominal current. The most stressed parts are excessively heated. In next part are projected a few options to optimize the current path. The options are verified by simulation. The best option is recommended to the submitter.
107

Phospholamban - Identification of novel interaction partners

Kownatzki-Danger, Daniel 03 June 2021 (has links)
No description available.
108

Spatial Replay Protection for Proximity Services : Security and privacy aspects

Lindblom, Fredrik January 2016 (has links)
Proximity Services is a new feature in the 3rd Generation Partnership Project (3GPP) standard for mobile communication. This features gives the opportunity to provide services locally if the targets are sufficiently close. However, in the current version of the proposed specification, there is no protection against a malicious user tunneling messages to a remote location to give the impression of proximity. This thesis proposes solutions to protect against such a spatial replay attack and evaluates these solutions based on how the user’s integrity is preserved, their complexity, and the added overhead. It is not obvious today what the consequences of a spatial replay attack are and how serious such an attack could be. However, once the feature is deployed and people start using it, it could prove to be a major vulnerability. The methods presented in this thesis could be used to prevent spatial replay in 3GPP or similar standards proximity services. The chosen method is a geographical packet leash based on a poly-cylindrical grid for which only a certain amount of Least Significant Bits of the grid cell identifier is included in the initial Discovery Message and the rest could be used in the calculation of the Message Authentication Code. / Proximity Services är en ny funktion inom 3rd Generation Partnership Project (3GPP) standard för mobil kommunikation. Den möjliggör att erbjuda tjänster lokalt om de tänkta användarna är tillräckligt nära. I den nuvarande versionen av specifikationen så finns det dock inget som hindrar en tredje part med onda avsikter från att tunnla meddelanden från den ursprungliga platsen till en annan som inte är i närheten för att ge intrycket till mottagaren att sändaren finns nära. Det här examensarbetet föreslår lösningar för att begränsa nämnda attack och utvärderar dem efter hur de påverkar användarnas platssekretess, lösningens komplexitet och den overhead de innebär. Det är idag inte uppenbart på vilket sätt den nämnda attacken skulle kunna påverka användarna och hur allvarliga konsekvenserna kan bli, men när standarden är implementerad och eventuella användare tillkommer så skulle det kunna visa sig innebära en stor risk. Lösningarna som presenteras i det här examensarbetet skulle kunna användas för att begränsa den här typen av attacker inom 3GPPs standard eller liknande baserade på närhet. Den metoden som har valts är ett ’geographical packet leash’ baserat på ett polycylindriskt rutnät för vilket endast en bestämd mängd minst signifikanta bitar är inkluderade i ett inledande Discovery Message medans resten kan användas i beräkningen av Message Authentication Code.
109

Global Spaces for Local Entrepreneurship : Stretching clusters through networks and international trade fairs

Ramírez-Pasillas, Marcela January 2007 (has links)
Many of the insightful writings on clusters identify the role of entrepreneurs as key agents in the formation of firms and clusters. This thesis argues instead that local entrepreneurship is not ceased once firms and clusters are established; local entrepreneurship is about the continuous (re)creation of both businesses and clusters in global spaces. Global spaces for local entrepreneurship emphasises how firms collectively become an agent of continuous renewal. Firms enact an organising context materialising in networks that stretch relations and collaborations according to the issues being dealt with. These networks are localised but are extended beyond the geographical boundaries of clusters. One important example of this, which is in focus in this doctoral thesis, is that firms operating in clusters often interact with actors whom they have met at international trade fairs (ITFs). ITFs are those attractive events that individuals, firms and institutions attend temporarily to exhibit and trade products in foreign and national markets. This thesis is based on the work contained in a cover and five papers. Each paper contributes to the research objective and questions brought forward in the thesis cover. The empirical evidence has been mostly drawn from several case studies conducted in the Lammhult cluster in Sweden. The findings show that firms build their organising contexts in order to stretch the reach and accessibility to local and non-local actors; they jointly co-create potential opportunities. The organising contexts are mapped in networks using three proximity orders. The empirical findings report three types of situations in which there is a potential opportunity for continuous renewal. By emphasising the opportunities that can be originated when a business is not realised or when a new or improved product or process has not been generated yet, this thesis aims to stimulate a theoretical reappraisal of global spaces for local entrepreneurship. With the conceptual development of global spaces for local entrepreneurship, we put forward the idea that such spaces enhance an ability to renew firms and clusters. The underlying reason is that local entrepreneurship is centered on the social interaction between individuals, firms and/or institutions; it materialises in intended and unintended dialogical situations when there is a commitment to the continuous renewal of firms and clusters. Such dialogical situations carry with them an opportunity for co-creating new businesses, new products and new processes.
110

Investigating magnetism and superconductivity using high magnetic fields

Ghannadzadeh, Saman January 2014 (has links)
This thesis investigates a number of transition-metal coordination polymers and iron-pnictide superconductors through the use of high magnetic fields, low temperatures, and on occasion, high pressures. The thesis will begin by describing my development of the proximity detector dynamic susceptometer, a novel technique that can be used for magnetometery and transport measurements in high magnetic fields. This technique is highly compact and has no moving parts, making it suitable for use in pressure cells, hence opening the way for a variety of new experiments. Through high-field magnetometery and other measurements, I will demonstrate that the pressure can be used to directly control the magnetic properties of the polymeric magnet CuF<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>(pyrazine). In particular, I observe a transition from quasi-two-dimensional to quasi-one-dimensional antiferromagnetism at 9~kbar, driven by the rotation of the Jahn-Teller axis. I will then present a series of measurements on two coordination polymers, showing how a small chemical difference can lead to drastically different magnetic properties. I show that [Cu(pyrazine)H<sub>2</sub>O(glycine)<sub>2</sub>]ClO<sub>4</sub> is an excellent spin-chain, while the sister compound [Cu(pyrazine)(glycine)]ClO<sub>4</sub> is a dimerised material that shows a spin-gap and is disordered down to very low temperatures, but then undergoes a field-induced phase transition to an ordered phase. I will also describe a series of pulsed-field measurements of the upper critical field of the iron-based superconductors NaFe<sub>1-x</sub>Co<sub>x</sub>As across the whole of the doping phase diagram. It is shown that paramagnetic pair-breaking effects dominate the critical field when the field is parallel to the crystal planes. In the parent compound the paramagnetic limit is equal to that expected from BCS theory, but becomes significantly enhanced above the BCS limit upon doping. It is shown that the multi-band nature of the superconductivity leads to a convex curvature in the evolution of the critical field as the temperature is reduced.

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