Topologically protected modes in dispersive materials: the case of undamped systems

This work extends the theory of topological protection to dispersive systems. This theory has emerged from the field of topological insulators and has been established for continuum models in both classical and quantum settings. It predicts the existence of localised interface modes based on associated topological indices and shows that, when such modes exist, they benefit from enhanced robustness with respect to imperfections. This makes topologically protected modes an ideal starting point for building wave guiding devices. However, in many practical applications such as optics or locally resonant meta-structures, materials are dispersive in the operating frequency range. In this case, the associated spectral theory is less straightforward. This work shows that the existing theory of topological protection can be extended to dispersive settings. We consider time-harmonic waves in one-dimensional systems with no damping

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Cyprus represents one of the most enduring and problematic regional conflicts. Since Cyprus' independence in 1960, the Greek and the Turkish Cypriots have been in conflict, culminating in the arrival of the UN Peace- keeping Force (UNFICYP) in 1964 and the 1974 Turkish invasion. The regional concerns of Greece and Turkey and their proclivity to protect and advance the interests of their related ethnic communities on the island have played serious roles in the maintenance of the conflict. The thesis illustrates the weakness of the international mediation effort and the obstacles to a settlement. Although third parties, such as the UN, the USA and the EU, are pressing the issue, a solution ultimately depends on the four key actors, the two Cypriot communities and Greece and Turkey, coming to a mutually acceptable agreement. More recently, the EU has become involved in the issue because of the intended accession negotiations for Cyprus, and its special relations with Greece - as an EU member - and Turkey, as an EU-membership candidate following the 1999 EU summit in Helsinki. Both the EU and USA calculate that a political federal solution of Cyprus' problems will benefit both Cypriot communities, improve Greek-Turkish relations, and formalize Turkey's European status.http://archive.org/details/internationalmed1094532929NANAHellenic Army author.Approved for public release; distribution is unlimited

Ethno-cultural background, bullying and victimization among adolescents

Σκοπός της παρούσας μελέτης ήταν να διερευνήσει το κατά πόσο συνδέεται η εθνο-πολιτισμική προέλευση με τα φαινόμενα του εκφοβισμού και της θυματοποίησης σε έφηβους μαθητές. Ειδικότερα, η έρευνα εξέτασε το πώς το φύλο, η εθνο-πολιτισμική προέλευση των συμμετεχόντων και η εθνο-πολιτισμική σύνθεση των σχολείων σχετίζονται με τον εκφοβισμό και τη θυματοποίηση λόγω-εθνο πολιτισμικής προέλευσης, με τις επιμέρους μορφές τους, καθώς και με την κατανομή των ρόλων των συμμετεχόντων στα φαινόμενα αυτά. Εκατό εξήντα τρεις (163) μαθητές από 5 εθνο-πολιτισμικές ομάδες, οιοποίοι φοιτούσαν σε 2 γυμνάσια του νομού Ροδόπης, ένα υψηλής εθνο-πολιτισμικής ετερότητας και ένα χαμηλής, συμπλήρωσαν ένα ερωτηματολόγιο αυτο-αναφοράς. Τα αποτελέσματα έδειξαν πως τα αγόρια-μέλη της κυρίαρχης εθνο-πολιτισμικής ομάδας παρουσίασαν υψηλότερες συνολικές βαθμολογίες στον εκφοβισμό και στη θυματοποίηση σε σχέση με τα κορίτσια της ίδιας ομάδας. Επίσης, οι χριστιανοί μαθητές ελληνικής εθνοπολιτισμικής προέλευσης σημείωσαν τη χαμηλότερη βαθμολογία σχετικά με τη θυματοποίηση, ενώ οι μουσουλμάνοι τουρκικής εθνο-πολιτισμικής προέλευσης την υψηλότερη. Μεταξύ των 2 σχολείων, στο σχολείο με τη μεγαλύτερη εθνο-πολιτισμικήετερότητα σημειώθηκε υψηλότερη βαθμολογία στον εκφοβισμό και στη θυματοποίηση λόγω εθνο-πολιτισμικής προέλευσης. Αναφορικά με τις επιμέρους μορφές των φαινομένων, οι μαθητές σημείωσαν υψηλή βαθμολογία στη λεκτική και στην έμμεση/κοινωνική μορφή των φαινομένων, με τα αγόρια να εμφανίζουν υψηλότερες βαθμολογίες και στις 3 μορφές του εκφοβισμού. Επίσης, στο σχολείο με τη μεγαλύτερηεθνο-πολιτισμική ετερότητα σημειώθηκε υψηλότερη βαθμολογία σε όλες τις μορφές των φαινομένων. Ως προς τους ρόλους των συμμετεχόντων, στον ρόλο του θύματος τα αγόρια εκπροσωπούνται χαμηλότερα, ενώ στον ρόλο του θύτη-θύματος υψηλότερα εκπροσωπούνται τα κορίτσια. Οι χριστιανοί μαθητές ελληνικής εθνο-πολιτισμικής προέλευσης παρουσίασαν τη μεγαλύτερη εκπροσώπηση στον ρόλο του θύτη, οιμουσουλμάνοι μαθητές τουρκικής εθνο-πολιτισμικής προέλευσης στον ρόλο των θυτώνθυμάτων και οι μουσουλμάνοι πομακικής, ρομανή και απροσδιόριστης εθνοπολιτισμικής προέλευσης στον ρόλο των θυμάτων. Τα ευρήματα συζητούνται ως προς τις παιδαγωγικές τους εφαρμογές.The purpose of this study was to investigate the relationship between ethnic-cultural background and bullying/victimization among adolescent students. In particular, the study examined how gender, ethnic-cultural background and ethnic-cultural school composition were related to bullying/victimization, as well as to its forms and the role assumed by the participants. 163 students from five ethnic-cultural groups attending two junior high schools, one with high and the other with low ethnic diversity, completed a self-report questionnaire. Data analysis revealed that boys, members of the dominant ethnic-cultural group, scored higher in bullying/victimization than girls in the same group. Furthermore, Orthodox Greek students scored lower in victimization, while Muslim Turkish students scored higher. Between the two schools, students attending the school with higher ethnic-cultural diversity scored higher in bullying and victimization. Regarding the forms of bullying/victimization, all students scored higher in verbal and indirect/social bullying, whileboys scored higher in physical bullying as well. Also, students attending the school with higher ethnic-cultural diversity had high scores in all forms of bullying/victimization. Regarding participants' role distribution, boys were less likely to be victims than girls. Orthodox Greek students were more likely to be bullies, Muslim Turkish students were both bullies and victims, while Muslim Pomak, Romany and undefined ethnic-cultural background students were more likely to be victims. Findings are discussed in terms of their pedagogical implication

Theoretical study of the effect of (001) TiO2 anatase support on V2O5

The effect of (001) TiO2 anatase support oil the electronic and catalytic properties of a V2O5 monolayer is analyzed using density functional theory (DFT). The catalyst is represented by both Clusters and periodic slabs. Using two experimentally relevant models of monolayer V2O5/TiO2 (anatase) catalyst, both weak and strong interactions between a V2O5 monolayer and the TiO2 Support have been investigated. In the first model, where if crystallographic (001) V2O5 layer is placed oil top of the (001) TiO2 support, the weak interaction between vanadia and titania does not result in a major reconstruction of the active phase. Nevertheless, the changes ill the electronic properties of the system are evident. The deposition of the vanadia monolayer oil the titania substrate results in Charge redistribution, enhancing the Lewis acidity of vanadium and the chemical hardness above the vanadyl oxygen, and in a shift of the Fermi level to lower binding energies accompanied by a reduction ill the band gap. In the second model, where the (001) titania anatase structure is extended with a VO2 film terminated by half a monolayer of vanadyl oxygen, apart from a similar electronic effect, the strong interaction of the vanadia phase with the titania support resulting from a high order of epitaxy has an important effect oil the Structure of the active phase. Atomic hydrogen adsorption is most favorable oil the vanadyl oxygen of all the investigated surfaces, while the adsorption energy oil this site increases by similar to 10 kJ/mol due to the weak interaction between vanadia and titania and is further increased by similar to 50 kJ/mol as a stronger interaction between the two phases is achieved, all in agreement with the increase in the negative electrostatic potential above the vanadyl site. The observed trends in the reactivity of the oxygen sites ill H adsorption for the different catalyst models are successfully explained in terms of a frontier orbital analysis