Osteochondral lesions of the talus (OLTs) are the third most common type of osteochondral lesion and can cause pain and instability of the ankle joint. Episurf Medical AB is a medical technology company that develops individualized implants for patients who are suffering from focal cartilage lesions. Episurf have recently started a project that aims to implement their implantation technique in the treatment of OLTs. This master thesis was a part of Episurf’s talus project and the main goal of the thesis was to find the optimal implantation angle of the Episurf implant when treating OLTs. The optimal implantation angle was defined as the angle that minimized the maximum equivalent (von Mises) strain acting on the implant shaft during the stance phase of a normal gait cycle. It is desirable to minimize the strain acting on the implant shaft, since a reduction of the strain can improve the longevity of the implant. To find the optimal implantation angle a finite element model of an ankle joint treated with the Episurf implant was developed. In the model an implant with a diameter of 12 millimeters was placed in the middle part of the medial side of the talar dome. An optimization algorithm was designed to find the implantation angle, which minimized the maximum equivalent strain acting on the implant shaft. The optimal implantation angle was found to be a sagittal angle of 12.5 degrees and a coronal angle of 0 degrees. Both the magnitude and the direction of the force applied to the ankle joint in the simulated stance phase seemed to influence the maximum equivalent strain acting on the implant shaft. A number of simplifications have been done in the simulation of this project, which might affect the accuracy of the results. Therefore it is recommended that further, more detailed, simulations based on this project are performed in order to improve the result accuracy. / Fokala broskskador på talusbenet är den tredje vanligaste typen av fokala broskskador och kan ge upphov till smärta och instabilitet av fotleden. Episurf Medical AB är ett medicintekniskt företag som utvecklar individanpassade implantat för patienter med fokala broskskador. Episurf har nyligen påbörjat ett projekt där deras teknik ska användas i behandlingen av fokala broskskador på talusbenet. Den här masteruppsatsen var en del i Episurfs talusprojekt och dess huvudmål var att finna den optimala implantationsvinkeln av Episurfs implantat i behandlingen av fokala broskskador på talusbenet. Den optimala implanteringsvinkeln definierades som den vinkel som minimerade den effektiva von Mises-töjningen som verkade på implantatskaftet under stance-fasen i en normal gångcykel. Det är eftersträvansvärt att minimera belastningen på implantatskaftet eftersom en reducering av belastningen kan förbättra implantatets livslängd. En finita element-modell av en fotled behandlad med Episurfs implantat utvecklades för att för att finna den optimala implantationsvinkeln. I modellen placerades ett implantat med en diameter på 12 millimeter på mittendelen av talus mediala sida. En optimeringsalgoritm utformades för att finna implantationsvinkeln som minimerade den effektiva von Mises-töjningen på implantatskaftet. Den funna optimala implantationsvinkeln bestod av en vinkel på 12.5 grader i sagittalplan och en vinkel på 0 grader i koronalplan. Både storleken och riktningen på kraften som applicerats på fotleden under den simulerade stance-fasen av gångcykeln verkade påverka belastningen på implantatskaftet. Ett antal förenklingar har gjorts i projektets simuleringar, vilket kan påverka noggrannheten i resultatet. Därför rekommenderas att ytterligare, mer detaljerade simuleringar baserade på det här projektet görs för att förbättra resultatets noggrannhet.

Le lupus érythémateux disséminé est une maladie auto-immune systémique chronique dont les atteintes sont multiples, l’atteinte rénale constituant la plus sévère. Une conjonction de facteurs génétiques et environnementaux conduit au développement de la maladie qui se traduit par une rupture de tolérance au soi. L’un des signes biologiques majeurs est la production d’auto-anticorps dirigés contre des composants nucléaires qui, en se déposant dans divers tissus dont les reins, génèrent une inflammation chronique conduisant au dysfonctionnement de l’organe. Le dépôt d’autoanticorps s’accompagne d’infiltrats de cellules immunitaires, qui, dans ce type d’inflammation, peuvent se transformer en structures lymphoïdes ectopiques fonctionnelles appelées Organes Lymphoïdes Tertiaires (OLT). Des OLT sont retrouvés dans diverses pathologies et participent à la génération locale de réponses immunitaires bénéfiques (infections/cancers) ou délétères (maladies auto-immunes). Mon projet de thèse a porté sur la mise en évidence d’OLT dans les reins au cours du lupus et sur l’étude des mécanismes permettant leur formation. Nous avons tout d’abord caractérisé les infiltrats inflammatoires présents dans les reins de souris NZB/W, modèle murin spontané de lupus. Ces infiltrats sont hautement organisés et constituent des OLT fonctionnels, potentiellement impliqués dans la néphrite lupique. Nous nous sommes ensuite intéressés aux mécanismes de mise en place de ces OLT et avons identifié les lymphocytes T et le récepteur aux chimiokines CXCR3 comme des éléments clés de ce processus et de la pathologie lupique. Les données obtenues apportent une meilleure compréhension fondamentale de la néogenèse lymphoïde au cours du lupus et ouvrent la voie vers de nouvelles stratégies thérapeutiques permettant de traiter la néphrite lupique. / Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease with multiple outcomes, with renal damage being the most severe. A combination of genetic and environmental factors leads to the development of the disease, which results in a break of immune tolerance. One of the major biological signs is the production of autoantibodies to nuclear components that, by depositing in various tissues including the kidneys, generate chronic inflammation leading to organ dysfunction. Deposition of autoantibodies is accompanied by immune cell infiltrates, which in this type of inflammation can be transformed into functional ectopic lymphoid structures called Tertiary Lymphoid Organs (TLO). TLO are found in various diseases and participate in the local generation of beneficial (infections / cancers) or deleterious (autoimmune diseases) immune responses. My thesis project focused on the demonstration of TLO in the kidneys during lupus and on the study of the mechanisms allowing their formation. We first characterized the inflammatory infiltrates present in the kidneys of NZB/W mice, a spontaneous murine model of lupus. These infiltrates are highly organized and constitute functional TLO that are potentially implicated in lupus nephritis. We then investigated the mechanisms of development of these TLO and identified T lymphocytes and the CXCR3 chemokine receptor as key components of this process and lupus pathology. The data obtained provide a better understanding of lymphoid neogenesis during lupus and pave the way for new therapeutic strategies to treat lupus nephritis.

This diploma thesis deals with the historical development of passive optical networks, according to the standards that was defined by International Telecommunication Union (APON, BPON, GPON, XG-PON and NG-PON). Further, the thesis describes the security of passive optical networks, but also a security threats which the deployment and use of passive optical technology carry. In the introductory chapters of this thesis the passive optical networks are described. The following is a description of the standards of passive optical networks in terms of their historical development. The next part is dedicated to the security of passive optical networks and possible security threats. In conclusion a description of the practical part of this thesis is given -- rack assembly, which will serve for future testing. The basic configuration of the optical line terminations that are fitted in the rack is also described. The last part of this diploma thesis is dedicated to the testing of selected security risks, which was described in the theoretical part of this thesis.

This thesis deals with DBA algorithms used in XG-PON networks. It describes reference appearance of the DBA algorithm, as well as, three specific DBA algorithms discussed in professional articles. Particularly speaking about GIANT, HYRA and modified Max-Min Fair DBA. The thesis provides description of frames utilized by DBA algorithms in XG-PON networks, specifically XGEM frame and XGTC frames. The thesis also presents a simulation tester of DBA algorithms tested on a virtual XG-PON network. Finally, it contains the results of testing these DBA algorithms with a description.

Recent studies on growth of telecomm sector depict an ever rising demand for high bandwidth applications such as on-line gaming, high definition television and many more. This demand is coupled with increase in internet connected utilities per house hold - each requiring a portion of bandwidth. The fast development of broadband telecommunication services calls for an upgrade of access infrastructure. This challenge could be met by technologies such as Fiber-To-The-Home/Building (FTTH/B) point-to-multipoint (P2MP) optical access networking. Further, FTTH is also widely regarded as a future proof solution for broadband telecommunication services within scientific and industrial sectors. This has encouraged large amount of research and development throughout the globe to find optimal topologies for FTTH. OFDM based optical access network topology abbreviated as OTONES is an ongoing EU FP 7 project under the PIANO+ framework. The OTONES project addresses the next generation optical access networking on the basis of Orthogonal Frequency Division Multiplexing (OFDM) and Orthogonal Frequency Multiple Access (OFDMA), with special provision for reduced complexity and signal processing aspects of the subscriber side terminals (ONUs). This thesis focuses on the theoretical investigation of OFDM based optical access network topology OTONES. The thesis provides an in depth view of the salient aspects of the topology and formulates the key requirements of OTONES topology. The investigation primarily delves on two important aspects of the topology. First, finding the optimal analog circuitry for the optical network unit (ONU). Second, finding the optimal operation regime for the topology and hence optimizing the system level concept. In this thesis, we show that the requirement of an analog circuitry originates from the need of successive up-conversions in OTONES topology which also produces image spectrum. This image spectrum causes a 3 dB loss in power and spectral efficiency in absence of a proper image rejection circuitry. Thus, we discuss the generic SSB generation methods for efficient image rejection. Novel Bedrosian method based on Bedrosian Theorem is established as a promising method for image rejection. We show that this method is an analog implementation of Hilbert Transform Method and does not involve any approximation. Both generic methods for SSB along with the Novel Bedrosian method are evaluated based on the criterion established for OTONES topology. Finally, optical filtering from the set of generic SSB method is proposed for the downstream path and Novel Bedrosian method is proposed for the upstream path. The tolerance limits for Novel Bedrosian method, are also established for its physical implementation. We further discuss the realistic implementation of various components of the OTONES topology. We also establish the optimal operation regime of the full concurrent topology based on parameters such as input optical power, pilot tone separation and many more. Finally as a key feature of the thesis, we optimize the system level concept of the topology with the use of the proposed Novel Bedrosian Method as the optimal analog circuitry for OTONES topology and provide a region of optimal operation of the topology.