Techn. Universiẗat, Diss., 2002--Braunschweig.

Tierärztl. Hochsch., Diss., 2003--Hannover.

Tierärztl. Hochsch., Diss., 2004--Hannover.

Tierärztl. Hochsch., Diss., 2004--Hannover.

Univ., Diss., 2006--Giessen

Η ψηφιακή εποχή έχει διεισδύσει σε όλες τις πτυχές της ανθρώπινης δραστηριότητας και τις μεταμορφώνει με έναν επαναστατικό και πρωτόγνωρο τρόπο. Ένας ιδιαίτερος ευαίσθητος τομέας για εμάς τους Έλληνες, ο πολιτισμός, δεν θα μπορούσε να μείνει ανεπηρέαστος από το κύμα της ψηφιακής εποχής. Η ψηφιακή εποχή έχει μεταμορφώσει τη πολιτιστική κληρονομιά τόσο από άποψη δημιουργίας όσο και από άποψη διατήρησης πολιτισμού. Ενώ κάποτε συλλέγαμε φυσικά αντικείμενα όπως ζωγραφιές, βιβλία και αγάλματα, τώρα πλέον διατηρούμε και ψηφιακές αναπαραστάσεις των πολιτιστικών αντικειμένων. Μέσω των νέων τεχνολογιών της Πληροφορικής και των Επικοινωνιών μπορούν να δημιουργηθούν, ταυτοποιηθούν και να ανακτηθούν τα ψηφιακά αυτά αγαθά. Η πολιτιστική κληρονομιά έχει κερδίσει μεγάλο ενδιαφέρον τα τελευταία χρόνια. Η επιστημονική κοινότητα ερευνά τις πιθανότητες για παροχή κατάλληλων τεχνολογιών για ολοκληρωμένη πρόσβαση στις συλλογές πολιτισμικής κληρονομιάς, ενώ οι οργανισμοί πολιτισμικής κληρονομιάς γίνονται ολοένα πιο πρόθυμοι να συνεργαστούν και να παρέχουν την καλύτερη δυνατή πρόσβαση στις συλλογές τους μέσα από εξατομικευμένη παρουσίαση και πλοήγηση. Ο Σημασιολογικός Ιστός βρίσκεται στο επίκεντρο της προσπάθειας αυτής. Ο Σημασιολογικός Ιστός είναι το επόμενο στάδιο του σημερινού Διαδικτύου κατά το οποίο, τα δεδομένα θα επισημειώνονται με μεταδεδομένα, τα οποία θα επιτρέπουν στις εφαρμογές του Διαδικτύου να προσφέρουν καλύτερες υπηρεσίες αναζήτησης στο χρήστη. Η διπλωματική αυτή πραγματεύεται τη χρήση των τεχνολογιών του Σημασιολογικού Ιστού για την βελτίωση της πρόσβασης σε πολιτισμικά δεδομένα. Έχει ως στόχο την εμβάθυνση στις τεχνολογίες Σημασιολογικού Ιστού, στην ανάπτυξη μιας καινοτόμου εφαρμογής και στην ανάδειξη των πλεονεκτημάτων. Στο δεύτερο κεφάλαιο παρουσιάζεται πως ο Σημασιολογικός Ιστός λύνει το πρόβλημα της συντακτικής συμβατότητας. Συγκεκριμένα, παρουσιάζεται η τεχνολογία της XML και των διάφορων τεχνολογιών γύρω από αυτήν. Στο τρίτο και στο τέταρτο κεφάλαιο παρουσιάζεται πως επιτυγχάνεται η Σημασιολογική Συμβατότητα. Στο τρίτο κεφάλαιο μελετάται το RDF μοντέλο δεδομένων, η μοντελοποίηση δεδομένων στο Σημασιολογικό Ιστό. Παρουσιάζονται οι διάφοροι τρόποι σύνταξης του καθώς και πως γίνεται αναζήτηση σε γράφους RDF με το πρωτόκολλο SPARQL. Στο τέταρτο κεφάλαιο παρουσιάζεται η έννοια της οντολογίας. Παρουσιάζονται διάφορες γλώσσες περιγραφής οντολογιών ενώ μελετάται σε βάθος η OWL. Στο πέμπτο κεφάλαιο παρουσιάζεται ένα σύνολο θησαυρών και οντολογιών που χρησιμοποιούνται περισσότερο από τους οργανισμούς. Παρουσιάζεται η οντολογία SKOS καθώς και μέθοδοι για τη μεταφορά παραδοσιακών θησαυρών στο Σημασιολογικό Ιστό μέσω του SKOS. Τέλος, παρουσιάζεται το CIDOC-CRM ως μία λύση για την ολοκλήρωση θησαυρών ποικιλίας γνωστικών πεδίων. Στο έκτο κεφάλαιο γίνεται μία ανασκόπηση από επιλεγμένα έργα των τελευταίων ετών που χαρακτηρίζονται από την εφαρμογή των τεχνολογιών του Σημασιολογικού Ιστού στο τομέα του Πολιτισμού και της Πολιτισμικής Κληρονομιάς. Τέλος στο έβδομο κεφάλαιο παρουσιάζεται μία εφαρμογή διαχείρισης πολιτιστικών δρώμενων. Επίσης παρουσιάζεται η πρωτοβουλία των Διασυνδεδεμένων Δεδομένων και πως γίνεται η εφαρμογή μας γίνεται μέρος του Σημασιολογικού Ιστού μέσω της πρωτοβουλίας αυτής. / The digital age has influenced every aspect of human activity and has transformed them in a revolutionary, previously unseen way. A special for us Greeks sector, cultural heritage, could not stay unaffected from the wave of the digital age. The Digital age has transformed Cultural Heritage both from the aspect of creation and the aspect of conservation of civilization. While once we collected only physical objects like paintings, books and statues, now we also collect digital representations of cultural objects. Through the new ICTs the objects can be created, authenticated and retrieved. The domain of Cultural Heritage has gained a lot of popularity during the last years. The scientific community researches new possibilities for integrated access of collections of cultural heritage, while the organizations of cultural heritage are increasingly eager to cooperate and provide the best possible access to their collections through personalized presentation and navigation. The Semantic Web stands in the center of this effort. The Semantic Web is the next stage of today’s Internet, in which, data are annotated with metadata that enable novel applications of the Internet to provide better search services to the user. This thesis researches the usage of Semantic Web technologies for the enhancement of the access to cultural data. Its goal is the study of Semantic Web technologies and the development of a novel application to emphasize its advantages. In the second chapter is presented the XML, which is the vehicle of Semantic Web data representations .In the third chapter , the RDF model is presented. Specifically, the various syntaxes of RDF and how RDF graphs are queried. In the fourth chapter the concept of the ontology is studied. Many ontology description languages are presented and OWL is studied more in depth. In the fifth chapter a number of thesaurus and ontologies are presented that are used by many CH organizations. The SKOS ontology is presented as well as the methods employed to migrate legacy thesauri to the Semantic Web. Also, the CIDOC-CRM ontology is presented as a solution for the integration of various domains. In the sixth chapter a review of selected projects of the last years is presented, that are characterized by the application of the technologies of Semantic Web in the sector of Culture and Cultural heritage. In the last chapter an application of cultural events management is presented. The initiative of Linked Data is also presented and how the application becomes a part of the Semantic Web through this initiative.

X-Linked Retinoschisis (XLRS) is a currently incurable, progressive retinal degeneration that affects approximately 1:20,000 males. Sufferers have a loss of retinal structure and visual acuity, leading to blindness. The condition is caused by mutation of the RS1 gene encoding the retinal-specific protein retinoschisin. Retinoschisin is critical in maintaining the normal, ordered retinal architecture, with deletion in mice models leading to loss of both structure and visual processing, analogous to XLRS sufferers. However, re-introduction of retinoschisin using adeno-associated viral vectors leads to complete rescue in these models. Despite the importance of retinoschisin in maintaining retinal architecture, the mechanism by which it maintains this structure remains unknown. As a result, this study aimed to structurally characterise retinoschisin and XLRS-associated point mutants R141H and H207Q to gain insight into the mechanism of retinoschisin action. To this end, retinoschisin was expressed and purified from HEK 293-EBNA cells and the structure of both monomeric and octameric retinoschisin was investigated using Small-Angle X-Ray Scattering (SAXS) and Cryo-electron microscopy (Cryo-EM). Monomeric retinoschisin was found to adopt an elongated structure that allowed for the tight association of the subunits into a planer propeller structure. However, in solution conditions the octamer also stably self-assembled into a dimer of octamers, for which the structure was solved using cryo-EM. This allowed for construction of a quasi-atomic model, enabling mapping of XLRS-associated point mutations on the complex. Two major classes of mutation were identified, in the intra-octamer and inter-octamer interfaces, suggesting a mechanism of pathology for these mutants. Observation of clustered conservative mutations at the inter-octamer interface suggested the dimer of octamers may be physiologically relevant. Furthermore, comparison of the R141H mutant to the wild-type revealed an additional mutated site in the propeller tips. Here, R141H was suggested to induce a small conformational change and alter an interaction site. Another mutant, H207Q, however, induced a destabilization of the assembled retinoschisin molecule. In conclusion, we purified and structurally characterised human retinoschisin, identifying a new hexadecameric oligomer. The structure of this allowed for identification of distinct classes of mutations on the assembled molecule and a hypothesis of the mechanism of retinoschisin action in the retina.

In the last years, the number of freely available Linked and Open Data datasets has multiplied into tens of thousands. The numbers of applications taking advantage of it, however, have not. Thus, large portions of potentially valuable data remain unexploited and are inaccessible for lay users. Therefore the upfront investment in releasing data in the first place is hard to justify. The lack of applications needs to be addressed in order not to undermine efforts put into Linked and Open Data. In existing research, strong indicators can be found that the dearth of applications is due to a lack of pragmatic, working architectures supporting these applications and guiding developers. In this thesis, a new architecture for the integration and application of Linked and Open Data is presented. Fundamental design decisions are backed up by two studies: firstly, based on real-world Linked and Open Data samples, characteristic properties are identified. A key finding is the fact that large amounts of structured data display tabular structures, do not use clear licensing and involve multiple different file formats. Secondly, following on from that study, a comparison of storage choices in relevant query scenarios is made. It includes the de-facto standard storage choice in this domain, Triples Stores, as well as relational and NoSQL approaches. Results show significant performance deficiencies of some technologies in certain scenarios. Consequently, when integrating Linked and Open Data in scenarios with application-specific entities, the first choice of storage is relational databases. Combining these findings and related best practices of existing research, a prototype framework is implemented using Java 8 and Hibernate. As a proof-of-concept it is employed in an existing Linked and Open Data integration project. Thereby, it is shown that a best practice architectural component is introduced successfully, while development effort to implement specific program code can be simplified. Thus, the present work provides an important foundation for the development of semantic applications based on Linked and Open Data and potentially leads to a broader adoption of such applications.

Face au danger de la désinformation et de la prolifération de fake news (fausses nouvelles) sur le Web, la notion de véracité des données constitue un enjeu crucial. Dans ce contexte, il devient essentiel de développer des modèles qui évaluent de manière automatique la véracité des informations. De fait, cette évaluation est déjà très difficile pour un humain, en raison notamment du biais de confirmation qui empêche d’évaluer objectivement la fiabilité des informations. De plus, la quantité d'informations disponibles sur le Web rend cette tâche quasiment impossible. Il est donc nécessaire de disposer d'une grande puissance de calcul et de développer des méthodes capables d'automatiser cette tâche.Dans cette thèse, nous nous concentrons sur les modèles de découverte de la vérité. Ces approches analysent les assertions émises par différentes sources afin de déterminer celle qui est la plus fiable et digne de confiance. Cette étape est cruciale dans un processus d'extraction de connaissances, par exemple, pour constituer des bases de qualité, sur lesquelles pourront s'appuyer différents traitements ultérieurs (aide à la décision, recommandation, raisonnement…). Plus précisément, les modèles de la littérature sont des modèles non supervisés qui reposent sur un postulat : les informations exactes sont principalement fournies par des sources fiables et des sources fiables fournissent des informations exactes.Les approches existantes faisaient jusqu'ici abstraction de la connaissance a priori d'un domaine. Dans cette contribution, nous montrons comment les modèles de connaissance (ontologies de domaine) peuvent avantageusement être exploités pour améliorer les processus de recherche de vérité. Nous insistons principalement sur deux approches : la prise en compte de la hiérarchisation des concepts de l'ontologie et l'identification de motifs dans les connaissances qui permet, en exploitant certaines règles d'association, de renforcer la confiance dans certaines assertions. Dans le premier cas, deux valeurs différentes ne seront plus nécessairement considérées comme contradictoires ; elles peuvent, en effet, représenter le même concept mais avec des niveaux de détail différents. Pour intégrer cette composante dans les approches existantes, nous nous basons sur les modèles mathématiques associés aux ordres partiels. Dans le second cas, nous considérons des modèles récurrents (modélisés en utilisant des règles d'association) qui peuvent être dérivés à partir des ontologies et de bases de connaissances existantes. Ces informations supplémentaires peuvent renforcer la confiance dans certaines valeurs lorsque certains schémas récurrents sont observés. Chaque approche est validée sur différents jeux de données qui sont rendus disponibles à la communauté, tout comme le code de calcul correspondant aux deux approches. / The notion of data veracity is increasingly getting attention due to the problem of misinformation and fake news. With more and more published online information it is becoming essential to develop models that automatically evaluate information veracity. Indeed, the task of evaluating data veracity is very difficult for humans. They are affected by confirmation bias that prevents them to objectively evaluate the information reliability. Moreover, the amount of information that is available nowadays makes this task time-consuming. The computational power of computer is required. It is critical to develop methods that are able to automate this task.In this thesis we focus on Truth Discovery models. These approaches address the data veracity problem when conflicting values about the same properties of real-world entities are provided by multiple sources.They aim to identify which are the true claims among the set of conflicting ones. More precisely, they are unsupervised models that are based on the rationale stating that true information is provided by reliable sources and reliable sources provide true information. The main contribution of this thesis consists in improving Truth Discovery models considering a priori knowledge expressed in ontologies. This knowledge may facilitate the identification of true claims. Two particular aspects of ontologies are considered. First of all, we explore the semantic dependencies that may exist among different values, i.e. the ordering of values through certain conceptual relationships. Indeed, two different values are not necessary conflicting. They may represent the same concept, but with different levels of detail. In order to integrate this kind of knowledge into existing approaches, we use the mathematical models of partial order. Then, we consider recurrent patterns that can be derived from ontologies. This additional information indeed reinforces the confidence in certain values when certain recurrent patterns are observed. In this case, we model recurrent patterns using rules. Experiments that were conducted both on synthetic and real-world datasets show that a priori knowledge enhances existing models and paves the way towards a more reliable information world. Source code as well as synthetic and real-world datasets are freely available.

Orientador: Katia Denise Saraiva Bresciani / Banca: Carlos Noriyuki Kaneto / Banca: Solange Maria Gennari / Banca: Sílvia Helena Venturoli Perri / Banca: Jancarlo Ferreira Gomes / Resumo: Os objetivos deste trabalho foram comparar os métodos de diagnóstico por ensaio imunoenzimático (ELISA) de captura e reação em cadeia da polimerase (nested-PCR) à análise morfológica utilizando a técnica de centrífugo-flutuação em água-éter seguida de coloração de Kinyoun modificada (microscopia) para estimar a taxa de eliminação de oocistos de Cryptosporidium spp. na população de gatos domiciliados na zona urbana do Município de Araçatuba, São Paulo. O potencial zoonótico do coccídio isolado em fezes deste hospedeiro foi investigado por meio de caracterização molecular. Um total de 138 amostras fecais foi colhido de forma aleatória simples e proporcional à população de gatos de cada uma das sete áreas censitárias pertencentes à zona urbana do município. Não houve discordância entre ELISA de captura e microscopia (p = 1,0000) nem entre nested-PCR e microscopia (p = 0,1094); entretanto, o grau de concordância variou de substancial (Kappa = 0,7948) a moderado (Kappa = 0,4647), respectivamente, entre estes métodos. Especificidade da nested-PCR e do ELISA de captura foi semelhante; entretanto, a nested-PCR apresentou menor sensibilidade, justificada pela associação entre a intensidade da densidade óptica e a amplificação da subunidade 18S do rRNA. Detectamos oocistos de Cryptosporidium spp. em 9,4% das amostras por pelo menos dois métodos diagnósticos. Com intervalo de 95% de confiança, estimamos que a taxa de eliminação de oocistos desse protozoário na população felina do município variou de 4,5% a 14,3%. Todos os isolados sequenciados apresentaram 100% de similaridade com Cryptosporidium felis. Concluímos que gatos domiciliados possam contribuir para a contaminação ambiental de um município, ainda que C. felis não seja o principal agente etiológico da criptosporidiose em seres humanos / Abstract: The aim of this work was to compare the diagnostic methods by capture enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (nested-PCR) to morphological analysis using the technique of flotation in water-ether followed by modified Kinyoun staining (microscopy) to estimate the shedding rate of Cryptosporidium spp. in stool samples of cats domiciled in urban area of municipality of Araçatuba, São Paulo State. Zoonotic potential of coccidian isolated in feces was investigated by molecular characterization. A total of 138 stool samples were collected random and proportionally from to cat population in each of the seven census areas belonging to the urban area. There was no disagreement between capture ELISA and microscopy (p = 1.0000) or between nested-PCR and microscopy (p = 0.1094); however, the degree of agreement varied from substantial (Kappa = 0.7948) to moderate (Kappa = 0.4647), respectively, in these diagnostic methods. Specificity of nested-PCR and ELISA capture were similar; however, the nested-PCR showed lower sensitivity, justified by the association between the intensity of the optical density and amplification of 18S rRNA subunit. We detected Cryptosporidium spp. in 9.4% of the samples by at least two diagnostic methods. With the 95% confidence, we estimate that shedding rate of Cryptosporidium oocysts ranged from 4.5% to 14.3% in the feline population of Araçatuba. All isolates sequenced showed 100% similarity with Cryptosporidium felis. We conclude that cats domiciled can contribute to environmental contamination of a municipality, although C. felis is not the primary etiologic agent of cryptosporidiosis in humans / Doutor