Combining petrological and geochronological data we were able to show that rocks in south Naxos completed a full blueschist-/greenschist-facies metamorphic loop in about 10 Myr, distinctly faster than hitherto believed. We show that the high-pressure rocks reached peak pressure (16.3±0.9 kbar - 619 ±32°C) between 40.5±1.0 and 38.3±0.5 Ma and were re-equilibrated in the middle crust (3.8±1.1 kbar - 384±30 °C) under greenschist-facies metamorphism during in the Oligocene ~32 Ma. Our data indicate that this exhumation occurred at rates of 7.4±4.6 km Ma-1. Therefore, the Oligocene greenschist-facies overprint of the blueschist-facies rocks from south Naxos is unrelated to the Miocene amphibolite-/greenschist-facies metamorphism observed in Naxos. / Genom att kombinera petrologiska och geokronologiska data kan vi visa att bergarter på södra Naxos fullföljt en fullständig blåskiffer-/grönskiffer-facies metamorfisk loop på 10 Ma. Detta är mycket snabbare änn vad man tidigare trott. Vi visar att högtrycks bergarter nådde maximalt tryck (16.3±0.9 kbar - 619 ±32°C) mellan 40.5±1.0 och 38.3±0.5 Ma och var åter i jämnvikt i mitten av jordskorpan (3.8±1.1 kbar - 384±30 °C) under grönskiffer-facies metamorfism under Oligocen vid ~32 Ma.Våra data visar att exhumeringen skedde med hastigheter av 7.4±4.6 km Ma-1. Därför är den Oligocena grönskiffer-facies ersättningen av blåskiffer-facies på södra Naxos ej relaterad till den Miocena amfibolit-/grönskiffer-facies som observerats på Naxos. / En combinant les données pétrologiques et géochronologiques, nous avons été en mesure de montrer que les roches du Sud Naxos ont effectué un trajet complet en métamorphisme schiste bleue/schiste vert en 10 Ma, distinctement plus rapide que ce qui était admis jusqu’alors. Nous montrons que les roches de haute pression ont atteint un pic de pression (16.3±0.9 kbar - 619 ±32°C) entre 40.5±1.0 et 38.3±0.5 Ma et ont été rééquilibrées en croûte moyenne (3.8±1.1 kbar - 384±30 °C) en métamorphisme de facies schiste vert pendant l’Oligocène ~32 Ma. Nos données indiquent que cette exhumation a une vitesse de 7.4±4.6 km Ma-1. Par conséquent, la surimpression des roches de haute pression en métamorphisme de facies schiste vert dans le sud de Naxos n’est pas à relier au métamorphisme de facies amphibolite/schiste vert du Miocène observé à Naxos.

acase@tulane.edu

Introduction: Cardiac cell-cell junctions play important roles in maintaining cardiac integrity linking single cardiomyocytes into a single functioning syncytium. There are three main types of cell junctions in the heart: gap junctions (GJ), desmosomes (D) and adherens junctions (AJ). Mutations in the proteins which make-up these junctions are known to cause arrhythmogenic right ventricular cardiomyopathy (ARVC). Pathological features include progressive replacement of right ventricular cardiac muscle with fibrofatty tissue. This can lead to heart failure and life threatening arrhythmias. During normal development of the mammalian heart, protein components of AJ and D gradually fuse to form composite junctions at the intercalated discs, also called areae compositae (singular, area composita, AC). In contrast, the adult heart of lower vertebrates, including the zebrafish, may have few or no AC type junctions. The detailed structure of cardiomyocyte cell-cell junctions in the adult zebrafish heart remain poorly defined and their role in normal development, growth and response to injury have yet to be studied. This thesis will examine the hypothesis that localisation and distribution of myocardial cell-cell junction proteins are crucial in normal myocardial development and in endogenous cardiac regeneration and repair following injury. This will be achieved by understanding the normal development of cell-cell junction proteins in zebrafish from embryonic to adulthood. These findings will then be analysed in comparison to cell-cell junction proteins localisation and distribution in early and late mammalian (mouse and human) myocardium. Once a normal pattern of cell-cell junction proteins will be established, the localisation of cell-cell junction proteins in plakologbin mutant zebrafish model for cardiomyopathy will be studied to understand the distribution and localisation of these proteins in disease manifestation. This model will then be used to test if localisation of cell-cell junction proteins plays an important in cardiac repair following injury by using embryonic laser injury model, this will be further tested by drug intervention study to investigate underlying pathways such as Wnt signalling pathway. Methods: Myocardial cell-cell junctions were assessed using immunohistochemistry in embryonic, juvenile and adult zebrafish hearts and in foetal and adult human hearts. The Plakoglobin mutant zebrafish line (UAS:Gal-4:Plakoglobin Naxos; named as PGNx) was characterised using various functional and morphological assessments including histology, echocardiography and MRI scanning. Similar studies were undertaken in PGNx mutants at different developmental stages. A pharmacological intervention study, using a GSK-3 inhibitor, was carried out in PGNx mutants followed by cardiac structural and functional assessments. Laser-induced cardiac trauma was used to assess the response to injury and repair in normal and PGNx embryos following treatment with the GSK3 inhibitor drug. Results: Cell-cell junction patterning in the embryonic, juvenile and adult zebrafish heart shows a characteristic pearl string appearance of desmoplakin and β-catenin labelled distinct disc shaped AJ. Human foetal heart showed small distinct D and AJ, while the adult human heart had features consistent with AC type junctions. PGNx fish showed reduced ventricle ejection fraction, dilatation of the atrium, reduced amplitude of wall motion and ventricle relaxation velocity compared to age-matched controls. Echocardiography and MRI imaging confirmed severe atrial dilatation and restrictive ventricle physiology in adult fish. The cell-cell junction proteins were over-expressed in the zebrafish PG mutant (PGNx) hearts compared to age-matched controls. Drug studies using a GSK-3β inhibitor showed complete recovery of cardiac function and partial recovery of heart structure. Cardiac injury studies, using laser, showed failure of repair in PGNx embryos compared to age-matched controls. The GSK3 inhibitor failed to improve the functional response following heart laser injury. Conclusions: Cell-cell junctions are distributed abundantly around cardiomyocytes in the zebrafish heart during early development and into adulthood. In contrast to previous studies in adult mammalian heart, there was no evidence of AC type junctions in adult zebrafish cardiomyocytes. The mutant zebrafish line showed restrictive cardiac physiology and abnormal cardiac structure confirming the key role played by plakoglobin in the normal heart development. This is further supported by evidence showing failure of repair in PGNx mutant embryos after injury. Drug treatment with a GSK-3 inhibitor highlights a potentially novel therapeutic pathway for treatment of ARVC involving Wnt signalling.

Η Νάξος παρουσιάζει την ιδιαιτερότητα της διατήρησης μεγάλου αριθμού βυζαντινών ναών, πολλοί από τους οποίους χρονολογούνται στην πρώτη χιλιετία και, επομένως, προσφέρεται για τη μελέτη της εξέλιξης από την παλαιοχριστιανική στη μεσοβυζαντινή αρχιτεκτονική. Μετά από συνοπτική αναφορά στην μέχρι σήμερα έρευνα, την ιστορία και την τοπογραφία του νησιού, εξετάζονται συνολικά εξήντα πέντε μνημεία, με έμφαση σε όσα χρονολογούνται από το τέλος της παλαιοχριστιανικής περιόδου (μέσα 7ου αι.) έως την εποχή κατά την οποία αποκρυσταλλώθηκαν τα χαρακτηριστικά της μεσοβυζαντινής αρχιτεκτονικής (μέσα 11ου αι.). Στα τριάντα τέσσερα αυτά μνημεία αφιερώνεται ειδικό λήμμα, με περιγραφή, ανάλυση της οικοδομικής ιστορίας και βιβλιογραφία, το οποίο συνοδεύεται από σχέδια σε ενιαία κλίμακα 1:100, τις περισσότερες φορές πρωτότυπα. Η τεκμηρίωση των υπολοίπων μνημείων γίνεται συνοπτικότερα. Στη συνέχεια, γίνεται σύνθεση των παρατηρήσεων ως προς την τυπολογία, την κατασκευή, τις μορφές και τη χρονολόγηση των μνημείων, ούτως ώστε να διατυπωθούν τα τελικά συμπεράσματα, που αφορούν στην εξέλιξη της βυζαντινής ναοδομίας στο νησί, την ένταξη του φαινομένου στο πλαίσιο της βυζαντινής αρχιτεκτονικής και στην ιστορική του ερμηνεία. Τα συμπεράσματα της εργασίας συνοψίζονται στα ακόλουθα: 1. Μέχρι τα μέσα του 9ου αιώνος, η ναξιακή ναοδομία παρακολουθεί τη γενικότερη πορεία της αρχιτεκτονικής, αλλά καθορίζεται σε μεγάλο βαθμό από τις περιορισμένες οικονομικές και τεχνικές δυνατότητες που επιφέρει η ιστορική συγκυρία. Μετά από ένα κενό, που ταυτίζεται με την περίοδο της Αραβοκρατίας στην Κρήτη, αρχίζει μία περίοδος ανάκαμψης, που, ως τα μέσα του 11ου αιώνος, προσδιορίζεται από το παρελθόν, με ελάχιστα νέα στοιχεία. Μετά από τα μέσα του 11ου αιώνος, τα στοιχεία αυτά επικρατούν, ώστε να διαμορφωθεί ένα νέο ύφος, με χαρακτήρα λαϊκό και καταγωγή από την τοπική παράδοση, η οποία έχει ως αφετηρία την αρχιτεκτονική της όψιμης παλαιοχριστιανικής περιόδου. Οι επιδράσεις από την επίσημη αρχιτεκτονική του Βυζαντίου περιορίζονται σε ελάχιστα μνημεία. 2. Η ναξιακή ναοδομία δεν αποτελεί φαινόμενο τοπικό, αλλά μέρος μιας ευρύτερης ενότητας, τα γνωρίσματά της οποίας δεν οφείλονται σε συνειδητές κοινές μορφολογικές και αισθητικές επιλογές αλλά έχουν προκύψει από τη μετάπλαση των χαρακτηριστικών της παλαιοχριστιανικής αρχιτεκτονικής, στο πλαίσιο μιας μακρόχρονης εξελικτικής διαδικασίας. 3. Καθοριστικοί παράγοντες για την εξέλιξη της ναοδομίας στη Νάξο είναι: α) Η εμφάνιση της αραβικής απειλής στο δεύτερο μισό του 7ου αιώνος, β) Η κάμψη της επιθετικότητας των Αράβων στα μέσα του 8ου αιώνος και η σχετική ανάκαμψη του Βυζαντίου στο Αιγαίο, κατά την περίοδο που εν πολλοίς συμπίπτει με την Εικονομαχία, κατά τη διάρκεια της οποίας κτίζεται μεγάλος αριθμός ναών, γ) Η κατάληψη της Κρήτης από τους Άραβες, που συνεπάγεται μία περίοδο μεγάλης ανασφάλειας στο Αιγαίο και πιθανό έλεγχο ορισμένων νησιών. Ένα από αυτά ήταν και η Νάξος, η οποία μαρτυρείται πως ήταν υποτελής σε αυτούς κατά το έτος 904, δ) Η ανακατάληψη της Κρήτης από την Αυτοκρατορία και η αποκατάσταση της ειρήνης στο Αιγαίο, ε) Η πολιτική των Κομνηνών για τα νησιά του Αιγαίου. / Among the numerous churches preserved on the island of Naxos, a considerable number dates back to the first millennium. Therefore, Naxos offers an ideal opportunity for studying the evolution from Early-Christian to Middle-Byzantine architecture. After a brief account of the relevant bibliography as well as the history and topography of the island, sixty-five churches are examined, with emphasis to those which date from the end of the Early-Christian period (mid 7th century) to the time by which Middle-Byzantine architecture had acquired its main characteristics (mid 11th century). For each of these thirty-four churches there is a special entry, which includes a description, an account of its building history and bibliographical references. Each entry is followed by drawings on a scale of 1:100, in most cases original. The documentation of the remaining churches is less detailed. The comparative study of remarks on typology, construction, architectural forms and chronology, leads to the final conclusions on the evolution of church architecture, its integration to the general context of Byzantine architecture and its historical interpretation. The general conclusions sum up as follows: 1. Until the mid 9th century, church architecture in Naxos follows the current architectural advances, but is to a great extent defined by the economic and technical decline caused by historic circumstances. After a gap in construction, which coincides with the period of the Arab occupation of Crete, a period of prosperity follows, when church architecture, until the mid 11th century, is defined by the past and very few new characteristics are introduced. After the second half of the 11th century, these new elements prevail, and, thus, a new architectural style is created. The new style is informal in character and derives from local tradition, which, in turn, traces its origins back to the architecture of the post-Justinian era. The formal architecture of Byzantium has a very limited impact, which is apparent only in rare cases. 2. Church architecture in Naxos is not a local phenomenon, but forms part of a wider context, whose common features do not derive from conscious morphological and aesthetic choices, but have resulted from the long evolutionary process Early-Christian architecture underwent. 3. The evolution of church architecture in Naxos is defined by: a) The emergence of the menace of the Arabs in the second half of the 7th century, b) The attenuation of the Arab aggression in the mid-8th century and the relative rise of the Byzantine Empire in the Aegean, during a period which mostly coincides with Iconoclasm, when a large number of churches is built on the island, c) The conquest of Crete by the Arabs and, possibly, their control of some islands, which provokes a period of great insecurity in the Aegean. One of them is Naxos, which in the year 904 is mentioned to be subject to taxation to the Arabs, d) The re-conquest of Crete by the Empire and the re-establishment of peace in the Aegean, e) The policy of the Komnenoi for the Aegean islands.

Το παρόν πόνημα αποτελεί μια προσπάθεια καταγραφής του λεξικού του Φιλωτίτικου ιδιώματος της Νάξου. Επιπλέον είναι εμπλουτισμένο με εισαγωγή που περιγράφει τη διάλεκτο σε όλα τα επίπεδα ανάλυσης της γλώσσας (μορφολογία, σύνταξη, φωνολογία, λεξικό). / This assignment constitutes an attempt of recording the dialectical lexicon of Filoti, a village of the island of Naxos. In addition, it has an introduction that describes the dialect in all level of linguistics (morphology, syntax, phonology, lexicon).

No description available.

No description available.

Cette thèse a pour objectif de caractériser les circulations de fluides en contexte d’effondrement d’un prisme d’accrétion crustal. Le Metamorphic Core Complex (MCC) de Naxos comprend un système de détachement/décollement caractérisé par mylonites, ultramylonites, cataclasites et failles normales dont les relations géométriques témoignent du litage rhéologique de la croûte continentale. La chimie des inclusions fluides déterminée par l’analyse microthermométrique, la spectroscopie RAMAN, l’ablation laser couplée à l’analyse spectroscopique (LA-ICP-MS), le « crush-leach », et les signatures isotopiques C et H des inclusions fluides permettent d’identifier trois grands types de fluides (1) des fluides salés riche en métaux, ii) des fluides aquo-carboniques en équilibre avec les encaissants métamorphiques, et iii) des fluides aqueux, probablement d’origine météorique. Ces données indiquent que la croûte est subdivisée en deux réservoirs séparés par la transition fragile-ductile. Les fluides météoriques circulent en association avec la déformation fragile de la croûte supérieure alors que les fluides salés et les fluides aquo-carboniques circulent en relation avec la déformation ductile. La géométrie de ces réservoirs évolue lors de la formation du MCC, conjointement avec l’exhumation et le refroidissement des roches métamorphiques. Le passage des roches du réservoir ductile au réservoir fragile est associée à un changement depuis un gradient géothermique élevé (60-100°C/km) vers un gradient géothermique plus faible (35-60°C/km). La transition fragile-ductile correspond ainsi à la fois à une limite rhéologique corrélée à une limite thermique et une limite de perméabilité. / The aim of this thesis is to characterize fluid circulations in the context of the collapse of a crustal accretionary belt. The Naxos Metamorphic Core Complex comprises a detachment/decollement system characterized by mylonites, ultramylonites, cataclasites and normal faults with structural relationships reflecting the rheological layering at the crustal scale. Fluid inclusion chemistry is determined by microthermometry, Raman spectroscopy; laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), crush-leach and stable isotopes (C and H) analyses. These data characterize three different types of fluids: (1) high salinity fluids with a high metal content and high Th, (2) aqueous-carbonic fluids in equilibrium with the wall rocks and (3) aqueous probably surface-derived fluids. These data indicate that the crust is subdivided into two crustal reservoirs separated by the brittle/ductile transition. Surface-derived aqueous fluids circulate in association with the brittle deformation within the upper crust whereas aqueous-carbonic and high salinity fluids circulate in relation with ductile deformation. The characteristics of the trapped fluids indicate that as rocks have passed through the ductile/brittle transition they undergo a drastic change in geothermal gradient from 60 to 100°C/km within a lithostatic pressure regime to 35-60°C/km within a hydrostatic pressure regime. This implies that the fluid circulations are closely related to the rheological layering within the crust and its evolution during crustal extension. The ductile/brittle transition corresponds to a rheological boundary correlated to a thermal boundary and impermeable cap.

Urbanization in the Sikeliot apoikiai was the catalyst to the creation and reinforcement of polis identity from soon after the point of initial settlement onwards. A main priority of the Greek settlers was to first layout the foundations for an urban grid, and within this grid to designate space for ritual practice, later monumentalized during the Archaic and Classical periods following the growth of the polis. A diachronic and geographical survey of urbanization and of the religious architecture, art, and votives dating to the Archaic and Classical periods illustrates this; this survey centers around seven major Greek settlements in Sicily: Naxos, Megara Hyblaea, Syracuse, Himera, Gela, Akragas, and Selinus. While the process of urbanization also occurred on the Greek mainland, it was not prior to the phenomenon taking place in Sicily, rendering the Sikeliot poleis simply as imitations of mainland poleis as once argued; rather urbanization in Sicily occurred over a timeline parallel to that of the mainland. The development of Sikeliot trends and even prototypes in temple architecture and urban planning confirm this in the material evidence. There is also no evidence of the apoikiai in Sicily ever adopting poliadic deities, a traditional quality of polis identity within mainland poleis. Their polis identities were not rooted in the cult practice of poliadic deities, but in cult practice itself, which fostered a collective consciousness among polis inhabitants by virtue of shared ritual practice, reinforced by the monumentalization of religious space; cult practice is what affirmed and reaffirmed their polis identity. / Thesis / Master of Arts (MA)