Shifts in forms of knowledge and power in the field of education administration through reforms in greek educational policy, in the context of broader directions and european policies

This thesis examines changes in the governing of the Greek educational system, in the context of Europeanised and globalised discourse on education, through a critical approach grounded in the Sociology of Education and Educational Policy. We inquire into the ways in which the Heads of Education Directorates (HEDs) in Greece respond to the governance discourse which is implemented in the Greek educational system. The empirical research was carried out in the period between 2012 and 2015, and the data produced come from three sources: •Text analysis.•Semi-structured interviews.•Questionnaires. Addressing changes in education administration in Greece, in the context of Europeanisation and globalisation, we aim to analyse, on the one hand, the specific policies through which the educational authorities attempt to institute new forms of administrative practice and, on the other hand, the new forms of knowledge and power inscribed in the daily work of professionals within this field. Using discourse analysis techniques we have developed a set of in-depth analysis tools to trace the forms of governance discourse produced and reproduced in the field of education administration. The study uses the concepts of discourse and governmentality from the theory of Foucault and the theory of symbolic control and totally pedagogised society of Bernstein. One of the key findings of this study refers to the Official Recontextualising Field, which controls the rules of distribution, recontextualisation and assessment of knowledge. As a consequence of the dominant discourse on governance, this field has been strengthened as well as extended by the intrusion of experts from other fields, such as the economy, the culture, the legal studies and the entire field of public administration. Such experts become the agents for the transmission of new forms of power-knowledge within the field of education administration, transforming the roles of educational professionals and altering their practices. The instrumental and performative models of New Public Management and the competitive character that is attributed to the evaluation forms which are adopted in the field of education blur the image of schools as institutions with particular needs and political-social importance. Educational executives are expected to operate as self-regulated individuals, in order to achieve pre-specified targets, defined by agencies external to the field of education and under the control of state authorities.Η παρούσα διδακτορική διατριβή αφορά στη διερεύνηση του είδους των αλλαγών που λαμβάνουν χώρα σε σχέση με τη διακυβέρνηση του ελληνικού εκπαιδευτικού συστήματος στο πλαίσιο του μεταρρυθμιστικού προγράμματος του «Νέου Σχολείου» και ειδικά στις διαδικασίες επιλογής και τα προγράμματα επιμόρφωσης και πιστοποίησης της διοικητικής επάρκειας των Διευθυντών Πρωτοβάθμιας και Δευτεροβάθμιας Εκπαίδευσης (Δ.Ε.) που επιλέχθηκαν το 2010. Ειδικότερα, εξετάζονται οι μορφές γνώσης και εξουσίας που παράγονται, διαμορφώνονται και πραγματώνονται υπό την επίδραση του λόγου της Ευρωπαϊκής Ένωσης και άλλων υπερεθνικών φορέων σε σχέση με τα καθήκοντα και το έργο των Δ.Ε. και ερευνώνται τα πρότυπα ταυτότητας που θεωρούνται θεμιτά γι’ αυτά τα επαγγελματικά στελέχη. Κεντρικός στόχος της διατριβής είναι η μελέτη των αλλαγών και των μετατοπίσεων που λαμβάνουν χώρα στο πεδίο του συμβολικού ελέγχου και η επίδρασή τους στις σχέσεις των επαγγελματιών της εκπαίδευσης μεταξύ τους, με το ευρύτερο περιβάλλον του σχολείου, με τη διοικητική δομή και ιεραρχία καθώς και με την ίδια τη γνώση. Το ερευνητικό σχέδιο εστιάζει, επίσης, στις πρακτικές παιδαγωγικής και αξιολόγησης, που υιοθετούνται και πριμοδοτούνται από τα διοικητικά στελέχη της εκπαίδευσης στο πεδίο της καθημερινής διοικητικής και εκπαιδευτικής πράξης. Τα δεδομένα προέρχονται από εμπειρική έρευνα που εκπονήθηκε την περίοδο 2012-2015 μέσω: •Ανάλυσης εγγράφων.•Ημιδομημένων συνεντεύξεων.•Ερωτηματολόγιων.Η προσέγγισή μας εντάσσεται στην κοινωνιολογία της γνώσης και της εκπαιδευτικής πολιτικής. Χρησιμοποιώντας τεχνικές ανάλυσης λόγου αναπτύσσουμε ένα σύνολο εργαλείων ανάλυσης εις βάθος, για να ανιχνεύσουμε τις μορφές του λόγου για τη διακυβέρνηση που παράγονται και αναπαράγονται στο πεδίο της διοίκησης της εκπαίδευσης. Η μελέτη αξιοποιεί τις έννοιες του λόγου και της κυβερνησιμότητας από τη θεωρία του Foucault και τη θεωρία του συμβολικού ελέγχου και της καθολικά παιδαγωγημένης κοινωνίας του Bernstein. Ένα από τα βασικά ευρήματα της παρούσας διατριβής αφορά στο Επίσημο Πεδίο Αναπλαισίωσης, το οποίο ενισχύεται αλλά και διευρύνεται με την είσοδο ειδικών από άλλα πεδία, όπως αυτό της οικονομίας, του πολιτισμού, της νομικής επιστήμης και της ευρύτερης δημόσιας διοίκησης, οι οποίοι αναλαμβάνουν να μεταφέρουν και να μεταδώσουν στα στελέχη της εκπαίδευσης νέες μορφές εξουσίας-γνώσης. Οι νέες αυτές μορφές διαχέονται μέσω ενός παιδαγωγικού λόγου στο χώρο της διοίκησης της εκπαίδευσης, που έχει ως αποτέλεσμα την ενσωμάτωση και αφομοίωση του ευρωπαϊκού και παγκόσμιου λόγου για τη διακυβέρνηση της εκπαίδευσης ως λόγου με κύρος και επιρροή στους επαγγελματίες του πεδίου του συμβολικού ελέγχου. Τα εργαλειακά και επιτελεστικά πρότυπα του Νέου Διοικητισμού και ο ανταγωνιστικός χαρακτήρας που αποδίδεται στις μορφές αξιολόγησης που εισάγονται στο πεδίο της εκπαίδευσης θολώνουν την εικόνα του σχολείου ως χώρου με ιδιαίτερες ανάγκες και πολιτική-κοινωνική σημασία. Οι επαγγελματίες καλούνται να λειτουργήσουν αυτορρυθμιζόμενοι, επιδιώκοντας την επίτευξη συγκεκριμένων στόχων που προσδιορίζονται από πεδία εξωτερικά της εκπαίδευσης και κάτω από τον έλεγχο της κρατικής εξουσίας

A study of the mechanical properties of as-received and intraorally exposed single-crystal and polycrystalline orthodontic ceramic brackets

BACKGROUND: Although ceramic brackets have been extensively used for decades in orthodontics there is not till today any study focusing on the possible deterioration of mechanical properties after in vivo ageing. OBJECTIVES: To determine whether the mechanical properties of alumina orthodontic brackets change after intraoral ageing thereby assessing the validity of a theoretical model established for the performance of ceramics in wet environments. MATERIALS AND METHODS: Two alumina brackets, one single crystal (Radiance, American Orthodontics, Sheboygan, WI) and one polycrystalline (Clarity, 3M, St. Paul, MN) were included in this study. Ten brackets for each group were collected from different patients after a minimum of 3-month intraoral exposure, whereas as-received brackets of the same manufacturers were used as controls. The specimens were subjected to Raman spectroscopy and were then embedded in epoxy resin and metallographic ground and polished. The mechanical properties of four groups (radiance control: RAC, radiance-retrieved RAR, clarity control: CLC and clarity-retrieved CLR) were determined using instrumented indentation testing according to ISO 14577-2002. The mechanical properties tested were Martens hardness (HM), indentation modulus (EIT), the ratio of elastic to total work, commonly known as elastic index (ηIT), and fracture toughness (KIC). The numerical results were statistically analysed employing two-way analysis of variance (ANOVA) and Tukey multiple comparison test at a = 0.05. RESULTS: Raman analysis revealed that both brackets are made of a-Al2O3 (corundum). No statistically significant differences were found for HM (N/mm2): RAC = 7249 (1507), RAR = 6926 (1144), CLC = 8052 (1360), CLR = 7390 (2393), or for EIT (GPa): RAC = 141 (27), RAR = 139 (23), CLC = 139 (28), CLR = 131 (47). However, significant differences were identified between the two alumina brackets tested for ηIT (%): RAC = 55.7 (4.2), RAR = 54.0 (3.5), CLC = 62.5 (4.4), CLR = 61.8 (4.7), while KIC was measured only for the polycrystalline bracket (Clarity) because of the complicated fractured pattern of the single-crystal bracket. Both brackets share equal HM and EIT before and after orthodontic intraoral ageing. LIMITATIONS: Whereas the study assessed the changes after intraoral exposure per theoretical model, which describes the reduction of critical stress to induce fracture after wetting, long-term intraoral ageing could have induced more pronounced effects. CONCLUSIONS/IMPLICATIONS: The results of this study indicate that 3 months of intraoral ageing do not change the mechanical properties of single-crystal and polycrystalline orthodontic brackets tested, thus indicating that the Griffith theory may not be applied to the case of manufactured ceramic brackets owing possibly to internal defects

A study of the mechanical properties of as-received and intraorally exposed single-crystal and polycrystalline orthodontic ceramic brackets

Background: Although ceramic brackets have been extensively used for decades in orthodontics there is not till today any study focusing on the possible deterioration of mechanical properties after in vivo ageing. Objectives: To determine whether the mechanical properties of alumina orthodontic brackets change after intraoral ageing thereby assessing the validity of a theoretical model established for the performance of ceramics in wet environments. Materials and methods: Two alumina brackets, one single crystal (Radiance, American Orthodontics, Sheboygan, WI) and one polycrystalline (Clarity, 3M, St. Paul, MN) were included in this study. Ten brackets for each group were collected from different patients after a minimum of 3-month intraoral exposure, whereas as-received brackets of the same manufacturers were used as controls. The specimens were subjected to Raman spectroscopy and were then embedded in epoxy resin and metallographic ground and polished. The mechanical properties of four groups (radiance control: RAC, radiance-retrieved RAR, clarity control: CLC and clarity-retrieved CLR) were determined using instrumented indentation testing according to ISO 14577-2002. The mechanical properties tested were Martens hardness (HM), indentation modulus (EIT), the ratio of elastic to total work, commonly known as elastic index (ηIT), and fracture toughness (KIC). The numerical results were statistically analysed employing two-way analysis of variance (ANOVA) and Tukey multiple comparison test at a = 0.05. Results: Raman analysis revealed that both brackets are made of a-Al2O3 (corundum). No statistically significant differences were found for HM (N/mm2): RAC = 7249 (1507), RAR = 6926 (1144), CLC = 8052 (1360), CLR = 7390 (2393), or for EIT (GPa): RAC = 141 (27), RAR = 139 (23), CLC = 139 (28), CLR = 131 (47). However, significant differences were identified between the two alumina brackets tested for ηIT (%): RAC = 55.7 (4.2), RAR = 54.0 (3.5), CLC = 62.5 (4.4), CLR = 61.8 (4.7), while KIC was measured only for the polycrystalline bracket (Clarity) because of the complicated fractured pattern of the single-crystal bracket. Both brackets share equal HM and EIT before and after orthodontic intraoral ageing. Limitations: Whereas the study assessed the changes after intraoral exposure per theoretical model, which describes the reduction of critical stress to induce fracture after wetting, long-term intraoral ageing could have induced more pronounced effects. Conclusions/Implications: The results of this study indicate that 3 months of intraoral ageing do not change the mechanical properties of single-crystal and polycrystalline orthodontic brackets tested, thus indicating that the Griffith theory may not be applied to the case of manufactured ceramic brackets owing possibly to internal defects. © 2019 The Author(s). Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved