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No. of bitstreams: 2 Dissertação - Rodrigo Cesar Assis Caixeta - 2014.pdf: 3427166 bytes, checksum: 4e0cd6ad305c26afada6419c7fc8663c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-06-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / HPV, BV and CI are common conditions in adolescents and young women. Studies have reported that BV and CI can be cofactors for the acquisition and persistence of HPV, enabling the development of cytological abnormalities precursor of cervical cancer. The aim of this study was to estimate the prevalence of HPV, BV and IC in adolescents and young women and to verify that these conditions are associated with the detection of cytological abnormalities in cervical smears in adolescents and young women. Were included samples of sexually active patients and users of the Unified Health System (SUS) who underwent cervical screening by the conventional method. The cervical specimens were analyzed at the Center for Clinical Analysis Rômulo Rocha, Faculty of Pharmacy/UFG, by qualified professionals following strict quality control. The detection of HPV-DNA was made by PCR using pools of primers PGMY09/PGMY11. The diagnosis of BV was established from the observation of the presence of 20% or more of clue cells in cervical smears. The IC was assessed by counting the number of leukocytes in cervical smears in five noncontiguous with increased microscopic fields 1000X average, according Castle et al. (2001). Statistical analyzes with hierarchical logistic and control of confounding variables regression model were performed. The magnitude of association was estimated by calculating the odds ratio (OR) with confidence intervals (CI*) of 95%. 251 samples were included, with 54,9% (138/251) of adolescents aged between 15 and 19 years and 45,1% (113/251) of young women aged between 20 and 25 years. Positive results for cytological abnormalities accounted for 9,5% (24/251) of all cervical smears. The diagnosis of atypical squamous cells of undetermined significance (atypical squamous cells of undetermined significance - ASCUS) (50,0% 12/24) and squamous intraepithelial lesions (low grade squamous intraepithelial lesion - LSIL) (29,1 % 7/24) were more frequent. The overall prevalence of HPV, BV, and CI 44,2% (111/251), 41,0% (103/251) and 83,2% (209/251), respectively. Of the variables investigated, VB (OR = 2,46 CI*: 1,26 to 3,80; p: 0,006) and the detection of abnormal cytological diagnosis (OR = 1.36 CI*: 1.07 to 1.74; p: 0.013) were associated with HPV positivity in multivariate analysis. Whereas the detection of cytological abnormalities there was a significant association with HPV and BV detected in the same patient (OR = 2,59 CI*: 1,09 to 6,20; p: 0,032) and for the detection of HPV, BV and CI together (OR = 3,58 CI*: 1,06 to 12,15; p: 0,040), however, they didn’t remain independently associated in bivariate analysis. BV and cytological abnormalities were independently associated with HPV infection in adolescents and young women. HPV, BV and CI in cervical smears can indicate high possibility to detect cytological abnormalities in adolescents and young women. / HPV, VB e IC são condições frequentes em adolescentes e mulheres jovens. Estudos têm relatado que VB e IC podem ser cofatores para a aquisição e persistência do HPV, possibilitando o desenvolvimento de anormalidades citológicas precursoras do câncer do colo uterino. Assim, o objetivo desse estudo foi estimar a prevalência de HPV, VB e IC em adolescentes e mulheres jovens e verificar se estas condições estão associadas à detecção de anormalidades citológicas em esfregaços cervicais em adolescentes e mulheres. Foram incluídas amostras de pacientes sexualmente ativas e usuárias do Sistema Único de Saúde (SUS) que realizaram exame citopatológico através do método convencional. Os esfregaços cervicais foram analisados no Centro de Análises Clínicas Rômulo Rocha, da Faculdade de Farmácia/UFG, por profissionais qualificados e seguindo rigoroso controle de qualidade. A detecção de DNA do HPV foi feita por PCR, utilizando os pools de primers PGMY09/PGMY11. O diagnóstico de VB foi realizado a partir da observação da presença de 20% de células indicadoras nos esfregaços cervicais. A IC foi avaliada através da média da contagem do número de leucócitos nos esfregaços cervicais, em cinco campos microscópicos não adjacentes com aumento de 1000X, segundo Castle et al. (2001). Foram realizadas análises estatísticas com modelo de regressão logística hierárquica e controle de variáveis de confusão. A magnitude de associação foi estimada através do cálculo de odds ratio (OR) com intervalos de confiança (IC*) de 95%. Foram incluídas 251 amostras, sendo 54,9% (138/251) de adolescentes com faixa etária entre 15 e 19 anos e 45,1% (113/251) de mulheres jovens com idades entre 20 e 25 anos. Resultados positivos para anormalidades citológicas representaram 9,5% (24/251) do total de esfregaços cervicais. Os diagnósticos de células escamosas atípicas de significado indeterminado (Atypical Squamous Cells of Undetermined Significance – ASC-US) (50,0% 12/24) e lesão intraepitelial escamosa de baixo grau (Low grade Squamous Intraepithelial Lesion - LSIL) (29,1% 7/24) foram mais frequentes. As prevalências totais de HPV, VB e IC foram de 44,2% (111/251), 41,0% (103/251) e 83,2% (209/251), respectivamente. Das variáveis investigadas, VB (OR = 2,46 IC*: 1,26-3,80, p: 0,006) e a detecção de diagnóstico citológico anormal (OR = 1,36 IC*: 1,07-1,74, p: 0,013) foram associadas com a positividade para HPV pela análise multivariada. Considerando a detecção de anormalidades citológicas, houve uma associação significativa com o HPV e VB detectado no mesmo paciente (OR = 2,59 IC*: 1,09-6,20, p: 0,032), bem como para a detecção de HPV, VB e IC em conjunto (OR = 3,58 IC*: 1,06-12,15, p: 0,040), no entanto, eles não permaneceram independentemente associadas na análise bivariada. VB e esfregaço cervical anormal foram independentemente associados a infecção por HPV em adolescentes e mulheres jovens. HPV, VB e IC em esfregaços cervicais pode indicar uma maior possibilidade de detectar anormalidades citológicas em adolescentes e mulheres jovens.

Thesis Ranking of selected soft drinks manufacturers examines the performance of Coca Cola, Pepsi and Kofola through compilation of ranking. Within the thesis there are constucted four rankings based on four different criteria. The supreme criterion of performance is enterprise value obtained using the method of economic value added. Results stemming from compilation of the rankings are formulated as recommendations for potentnial investor in these companies. Results of individual rankings are compared with each other in order to examine the validity of the use of foreign sources of information for evaluation of the selected criteria.

The thesis attempts to address Orthodox Church concerns about the Protestant nature and ethos of the ecumenical movement, as it is encountered in the World Council of Churches, by examining Orthodox theological contributions to ecclesiology. This preliminary work is undertaken, as a first step, to establish points of dialogue with the theology of liberation and wider critical theories, in the search for a liberating ecumenism. At the same time, and in a second step (to follow the epistemology of the theology of liberation), this Orthodox theology is placed in a critical dialogue with the theology of liberation in the search for liberating ecclesiological perspectives that can contribute to the movement in ecumenism. This uneasy dialogue helps to recover absent epistemologies from ongoing ecumenical dialogues by re-reading orthodoxies, both ecumenical and ecclesiological, from a liberationist paradigm, and sets ecclesiology within the wider framework of contributions from critical theory. This dialogue between Orthodox theology and the theology of liberation helps to construct an ecclesiology that liberates ecumenism by setting ecclesiology and the ecumenical movement in the wider context of social movements. This thesis calls the ecumenical movement to ‘another possible world’ influenced by people-centred ecclesiologies, which transgresses the canonical boundaries in the ecumenical movement. To be ecumenical implies an Orthodox content to ecclesiology, otherwise the ecumenical movement is open to charges of pan-Protestantism. It is by embracing Orthodoxy that the ecumenical movement can move beyond hegemonic colonial projects and find a liberating praxis. This thesis proposes a dialogue that reflects the structure of the Final Report of the Special Commission on Orthodox Participation in the World Council of Churches. However, it engages with Orthodox ecclesiology and ecumenical histories from the perspective of the theology of liberation in the search for a liberating ecumenism and proposes a praxis that develops movement in the ecumenical and the ecclesiological through developing an ecclesiology from different peripheries of the Church.

Cette thèse est un travail en mathématiques appliquées. Elle aborde quelques problèmes en analyse d'images et utilise des outils mathématiques spécifiques.<br /><br />L'objectif des deux premières parties de cette thèse <br /> est de proposer un modèle pour décomposer une image f en trois composantes : f=u+v+w.<br />La première composante, u, contient l'information géométrique. On peut la considérer comme une esquisse de l'image originale f.<br />La seconde composante, v, contient l'information texture.<br />La troisième composante, w, contient le bruit présent dans l'image originale.<br />Notre approche repose sur l'utilisation d'espaces mathématiques <br />adaptés à chaque composante: l'espace BV des fonctions à variations bornées pour u, un espace G proche du dual de BV pour les textures, et un espace de Besov d'exposant négatif E pour le bruit.<br />Nous effectuons l'étude mathématique complète des différents modèles que nous proposons.<br />Nous illustrons notre approche par de nombreux exemples, et donnons deux applications concrètes : une première en restauration d'images RSO, et une seconde en compression d'images.<br /><br /><br />Dans la troisième et dernière partie de cette thèse, nous nous intéressons <br />spécifiquement à la composante texturée.<br />Nous proposons un algorithme de classification supervisée pour les images texturées. L'approche utilisée est basée sur l'utilisation de la méthode des contours actifs et d'un terme d'attache aux donnés spécifiques au textures. Ce dernier est construit à partir d'une transformée en paquets d'ondelettes. Nous obtenons ainsi une fonctionnelle, dont le minimum correspond à la classification cherchée. Nous résolvons numériquement ce problème à l'aide d'un système couplé d'EDP que nous plongeons dans un schéma dynamique. Nous illustrons notre démarche par de nombreux exemples numériques. Nous effectuons également l'étude théorique de la fonctionnelle de classification.

We study different aspects of perturbatively renormalized quantum gauge theories in the presence of non-trivial background Lorentzian metrics and background connections. First, we show that the proof of nilpotency of the renormalized interacting BRST charge can be reduced to the cohomological analysis of the classical BRST differential. This result guarantees the self-consistency of a class of local, renormalizable field theories with vanishing 'gauge anomaly'' at the quantum level, such as the pure Yang-Mills theory in four dimensions. Self-consistency here means that the algebra of gauge invariant observables can be constructed as the cohomology of this charge. Second, we give a proof of background independence of the Yang-Mills theory. We define background independent observables in a geometrical formulation as flat sections of a cohomology algebra bundle over the manifold of background configurations, with respect to a flat connection which implements background variations. We observe that background independence at the quantum level is potentially violated. We, however, show that the potential obstructions can be removed by a finite renormalization. Third, we construct the advanced/retarded Green's functions and Hadamard parametrices for linearized Yang-Mills and Einstein equations in general linear covariant gauges. They play an essential role in formulating gauge theories in curved spacetimes. Finally, we study a superconformal gauge theory in three dimensions (the ABJM theory) which is conformally coupled to a curved background. The superconformal symmetry of this theory is described by a conformal symmetry superalgebra on manifolds which admit twistor spinors. By analyzing the relevant cohomology class of an appropriate BV-BRST differential, we show that the full superalgebra is realized at the quantum level.

Le potassium (K+) est impliqué dans la régulation de l’excitabilité cellulaire, la régulation du cycle cellulaire, la viabilité cellulaire, la neuroprotection et le maintien des fonctions microgliales et oligodendrocytaires. Le dysfonctionnement des canaux potassiques, décrit dans plusieurs maladies neurodégénératives comme la Maladie d’Alzheimer (MA), la sclérose en plaques (SEP), la maladie de Parkinson et la maladie de Huntington, pourrait être une potentiel cible thérapeutique. Les mécanismes toxiques sous-jacents de ces pathologies neurodégénératives impliquent des oxystérols, dérivés oxydés du cholestérol, et des acides gras en relation avec le métabolisme peroxysomal. Le 7-cétocholestérol (7KC), le 24S-hydroxycholestérol (24S-OHC) et l'acide tétracosanoïque (C24: 0), souvent trouvés à des taux élevés au niveau du cerveau et dans le plasma de patients atteints de maladies neurodégénératives (MA, maladie de Nieman-Pick, SEP, maladie de Parkinson, maladie de Huntington et X-ALD conduisent une rupture de l’équilibre Redox qui aboutirait à la neurodégénérescence. Dans ce contexte, il est intéressant de déterminer l’éventuelle connexion entre environnement lipidique et homéostasie potassique. L’étude in vitro a été réalisée sur des olygodendrocytes murins 158N et les cellules microgliale BV-2. Nous avons montré que la lipotoxicité du 7KC, 24S-OHC et C24:0 implique une rétention du K+ faisant intervenir les canaux potassium voltage dépendant (Kv). Ces résultats ont montré que l'inhibition des canaux Kv conduisant à une augmentation la [K+]i contribue à la cytotoxicité du 7KC, 24S-OHC et C24:0. Nous nous sommes focalisés sur le canal Kv3.1b. La retention du K+ induite par les oxystérols (7KC et 24S-OHC) serait sous le contrôle de Kv3.1b. L’étude clinique réalisée sur du plasma de MA a révélé une corrélation négative entre le taux d’acide docosahexaénoïque (DHA) et la concentration de K+. Chez les souris transgéniques J20, modèle de la MA, l’étude de la topographie d’expression de Kv3.1b et d’Abcd3, au niveau de l’hippocampe et du cortex, a montré une baisse de l’expression de ces deux marqueurs. Dans leur ensemble, les résultats obtenus ont établi des relations entre lipotoxicité, métabolisme peroxysomal et altération de l’homéostasie potassique dans la neurodégénérescence et suggèrent une possible modulation de l’expression et de l’activité de kv3.1b dans la physiopathologie des maladies neurodégénératives. / Potassium (K+) is involved in the regulation of cellular excitability, cell cycle regulation, cell viability, neuroprotection and maintenance of microglial and oligodendrocytic functions. Potassium dysfunction, described in several neurodegenerative diseases such as Alzheimer's Disease (AD), multiple sclerosis (MS), Parkinson's disease and Huntington's disease, may be a potential therapeutic target. The underlying toxic mechanisms of these neurodegenerative pathologies involve oxysterols, which are oxidized cholesterol derivatives, and fatty acids including those associated with peroxisomal metabolism. 7-ketocholesterol (7KC), 24S-hydroxycholesterol (24S-OHC) and tetracosanoic acid (C24:0), often found at increased levels in the brain and plasma of patients with neurodegenerative diseases (Nieman-Pick disease, MS, Parkinson's disease, Huntington's disease and X-ALD) lead to a breakdown of the redox equilibrium leading to neurodegeneration. In this context, it is interesting to determine the possible connection between the lipid environment and potassium homeostasis The in vitro study was carried out on 158N murine oligodendrocytes and microglial BV-2 cells. We have shown that the lipotoxicity of 7KC, 24S-OHC and C24:0 implies retention of K+ involving the voltage dependent potassium channels (Kv). These results have shown that inhibition of Kv channels lead to an increase in [K +] i contributing to the cytotoxicity of 7KC, 24S-OHC and C24:0. The retention of K+ induced by oxysterols (7KC and 24S-OHC) would be under the control of Kv3.1b. A clinical study, on plasma of patients with Alzheimer’s disease, revealed a negative correlation between docosahexaenoic acid (DHA) and K+ concentration. In the J20 mice, a transgenic model of Alzheimer’s disease, the expression of Kv3.1b and Abcd3 was decreased in the hippocampus and cortex. Overall, the results obtained established relationships between lipotoxicity, peroxisomal metabolism and potassium homeostasis in neurodegeneration and suggest a possible modulation of the expression and activity of kv3.1b in the pathophysiology of neurodegenerative diseases. So, modulation of Kv3.1 could constitute a new therapeuthic approach against some neurodegenerative diseases.

Bakgrund: För att relativvärderingar inte skall bli missvisande sätts krav på att de jämförda bolagen faktiskt är tillräckligt lika för att tillåta en jämförelse. I praktiken väljs generellt bolag inom samma bransch, medan teorin förespråkar för att skillnader i finansiella variabler som bland annat tillväxt och risk måste kontrolleras för. Tidigare forskning har oftast endast studerat hur de finansiella variablerna påverkar multipelvärdet. Relativvärdering påverkas dock även av pågående marknadstrender, förutsatt att dessa trender influerar börsvärdet. Andra variabler än branschtillhörighet och finansiella sådana kan således påverka värdet och därmed även behöva kontrolleras för, innan en relativvärdering utförs. Hållbarhetsarbete är en sådan trend som vuxit sig väldigt stark på senare tid. Hållbarhetsarbete i allmänhet och ESG-betyg i synnerhet är områden som ännu inte är helt kartlagda, speciellt vad gäller deras påverkan på ett företags värdering. Syfte: Studiens syfte är att analysera om det föreligger några samband mellan ESG-betyg och multipelvärden samt hur dessa samband i så fall ser ut och varför, för svenska stora och medelstora bolag listade på Nasdaq Stockholm Large och Mid Cap. Metod: Studien har utförts med en kvantitativ strategi, där samband mellan ESG-betyg och multipelvärden undersökts för årsskiftet 2020/2021, genom multipla regressionsanalyser. Totalt 151 svenska bolag med erhållna ESG-betyg har analyserats genom att deras multipelvärden för fyra olika multiplar använts som beroende variabler, samt där ESG-betyg och ett antal finansiella kontrollvariabler utgjort oberoende variabler i regressionerna. Underlaget till studien har utgjorts av data från databasen Refinitiv samt årsredovisningar. Slutsats: Resultatet visar att ett statistiskt signifikant negativt samband föreligger mellan ESG-betyg och multipelvärden. Att lägre betyg går hand i hand med högre värdering och vice versa, är fallet genomgående för såväl Mid Cap som Large Cap. / Background: In order for relative valuation not to be misleading, it is required that the companies compared are in fact sufficiently equal to allow a comparison. In practice, these companies are generally chosen within the same industry, while theory advocates that differences in financial variables such as growth and risk are more important and must be controlled for. Previous research has mostly only studied how these financial variables affect the value of multiples. However, relative valuation is also affected by ongoing market trends, provided that these trends influence market value. Variables other than financial ones and industry affiliation may thus affect the value and have to be controlled for, before a relative valuation using multiples is performed. Sustainability is one such trend that has grown tremendously strong in recent times. Sustainability work in general and ESG scores in particular are areas that have not yet been fully mapped, especially in terms of their impact on a company’s valuation. Purpose: The purpose of this study is to analyze potential relationships between ESG scores and values of multiples, how these relationships look and why, for large and medium-large Swedish companies listed on the Nasdaq Stockholm Large and Mid Cap lists. Methodology: A quantitative approach was used for the study, where the relationship between ESG scores and values of multiples was examined for the turn of the year 2020/2021, through multiple regression analyzes. A total of 151 Swedish companies, with published ESG scores, were analyzed using their multiples’ values for four different multiples as dependent variables in the regressions. ESG scores and a number of financial control variables constituted the independent variables in said regressions. The basis for the study has consisted of data from the Refinitiv database and annual reports. Conclusions: The results show that there is a statistically significant negative relationship between ESG scores and the values of multiples. The fact that lower ESG scores go hand in hand with higher valuations and vice versa, is the case throughout for both Mid Cap as well as Large Cap.

In May 1856 the EFS (the Swedish Evangelical Mission Society), influenced by the new evangelism-movement, was established as an “internal mission” within the Church of Sweden. During the same period the “new evangelism” revival movement established regional organizations in order to coordinate the movement in different parts of the country. These regional organizations consisted of the movement’s local mission societies in a province or part of a province of Sweden. This study will focus on democracy and theological identity in the EFS through an analysis of how the regional organizations acted, what role they played, how the EFS was influenced by them and how the EFS decided to establish its own regional organization. One result of the earlier tensions between the regional mission organizations and the EFS was the establishment of the independent organizations Mission Covenant Church of Sweden (Svenska Missionsförbundet) (1878-) and Mission Society of Bible faithful Friends (Missionssällskapet Bibeltrogna Vänner) (1911-). This investigation looks into 17 of 36 regional mission organizations that existed. The time frame of the investigation is from the establishment of the EFS in 1856 to the establishment of the regional structure of the EFS in 1922. The EFS changed over time. The change of society and wishes from the movement’s local mission societies and regional mission organizations were agents in this transformation. An important result of this research is that this transformation of the EFS proceeded at a slow pace and with the preservation of the EFS’s theological identity.

In this thesis we study novel higher order total variation-based variational methods for digital image reconstruction. These methods are formulated in the context of Tikhonov regularisation. We focus on regularisation techniques in which the regulariser incorporates second order derivatives or a sophisticated combination of first and second order derivatives. The introduction of higher order derivatives in the regularisation process has been shown to be an advantage over the classical first order case, i.e., total variation regularisation, as classical artifacts such as the staircasing effect are significantly reduced or totally eliminated. Also in image inpainting the introduction of higher order derivatives in the regulariser turns out to be crucial to achieve interpolation across large gaps. First, we introduce, analyse and implement a combined first and second order regularisation method with applications in image denoising, deblurring and inpainting. The method, numerically realised by the split Bregman algorithm, is computationally efficient and capable of giving comparable results with total generalised variation (TGV), a state of the art higher order method. An additional experimental analysis is performed for image inpainting and an online demo is provided on the IPOL website (Image Processing Online). We also compute and study properties of exact solutions of the one dimensional total generalised variation problem with L^{2} data fitting term, for simple piecewise affine data functions, with or without jumps . This gives an insight on how this type of regularisation behaves and unravels the role of the TGV parameters. Finally, we introduce, study and analyse a novel non-local Hessian functional. We prove localisations of the non-local Hessian to the local analogue in several topologies and our analysis results in derivative-free characterisations of higher order Sobolev and BV spaces. An alternative formulation of a non-local Hessian functional is also introduced which is able to produce piecewise affine reconstructions in image denoising, outperforming TGV.

Im Rahmen einer experimentellen Vergleichsstudie zweier bildwandlergestützter Navigationssysteme wurde die 3D-bildwandlergestützte Navigation mit der 2D-bildwandlergestützten Navigation zur Pedikelschraubenplatzierung am Modell getestet. Neben der Präzision der Bohrungen in einem postoperativen CT wurden Bildqualität, Genauigkeit des 3D-Scans, Planbarkeit und Umsetzung der Bohrungen bewertet und verglichen. Mit der 3D- Bildwandler- Navigation wurden 38 der 40 Bohrungen exakt platziert (95%). Eine Planung wurde durch einen Softwarefehler der Alpha-Version auf dem Monitor falsch wiedergegeben. Bei einer weiteren Bohrung wurde der Bohrer verkantet, wodurch Bildschirmdarstellung und Realität voneinander abwichen. Daher kam es in einem Fall zu einer lateralen Perforation der Kortikalis im Bereich des Pedikels, im anderen zu einer kaudalen Perforation. Mit der 2D- Bildwandler- Navigation konnten alle 40 Schrauben ohne Pedikelperforation platziert werden. Zwei dieser Schrauben wurden durch die ventrale Kortikalis gebohrt. Beide Verfahren überzeugten durch hohe Präzision und Zuverlässigkeit. 3 der 4 Fehlplatzierungen waren Anwender einer Software bedingt. Eine optimierte Software und verbesserte Instrumente werden diese Fehlerquote weiter reduzieren. Voraussetzung für die 2D-bildwandlergestützten Navigation sind eine gute Bildqualität sowie normale anatomische Gegebenheiten für standardisierte Projektionen. Die neue 3D-bildwandlergestützter Navigation kombiniert die Vorteile der 2D-bildwandlergestützter Navigation und der CT- basierten Navigation mit einer Verringerung der Strahlenbelastung durch den Wegfall des präoperativen CT`s und somit der Einsatzmöglichkeit im akuten Notfall sowie nach intraoperativen Repositionsmanövern. Da kein Matching erforderlich ist, wird insbesondere bei traumatischer Verletzung oder tumorbedingter Veränderung der dorsalen Wirbelstrukturen ein großer Vorteil zur CT- basierten Navigation erwartet. Aufgrund der universellen Einsatzmöglichkeiten eines Bildwandlers wird für diese neue Technologie ein breites Indikationsspektrum angenommen. / An experimental study to compare 2D- and 3D- Computer-Assisted Fluoroscopic Navigation for pedicle screw placement. Each system was evaluated by a post-operative CT and included the comparison of the palpation of the pedicular canal, the image quality and the accuracy of planning and performance. For this purpose 40 screws have been set to 9 models of lumbar spine. Using the 3D-flouroscopy based navigation 38 from 40 (95%) drillings were placed correctly. One mistake was caused by an error of the navigation-software. The second mistake was due to a drilling mistake, the drill was not shown correctly on the monitor because the drill has been canted. Using the 2D-flouroscopy based navigation all screws could be placed correctly at the pedicle, but two times the corpus has been perforated to ventral. Both techniques are precise and reliable. 3 out of 4 mistakes were caused by incorrect handling the instrument. The other mistake happened because of a software-error. If the software and the instruments will be optimised, the amount of mistakes will be reduced in the future. In case of the 2D-flouroscopy based navigation sufficient image quality, normal anatomical structures and defined projections are required. The new 3D-flouroscopy based navigation combines the benefit of 2D-flouroscopy based navigation and CT-based navigation by reducing the radiation exposure and the preoperative planning time. Therefore, this technique is suitable for use in an emergency or intraoperative repositions. Because no matching-procedure is necessary for CT-based navigation, we expect advantages especially in therapy of traumatic injuries or changes at the dorsal structures of spine caused by tumour. Furthermore, the use of fluoroscopic based navigation extends the range of applications/the spectrum of indication for this new technology.