New results of Hominoid research in the Carpathian Basin

Within the dynamic tectonic realm of the Carpathian Basin five succesive primate first appearance events has documented: Griphopithecus darwini and Pliopithecus (ca. 15 M years), Dryopithecus carinthiacus (ca. 12.5 M years), Dryopithecus brancoi (= Rudapithecus hungaricus) and Anapithecus hernyaki (ca. 10 M years), Mesopithecus pentelici (between 8 and 5.5 M years), and Dolicopithecus sp.(terminal Miocene and middle Pliocene). In 1998 an associated femoral remains of adult Anapithecus were discovered at Rudabánya. RUD-184 has a large and almost perfectly spherical head, a very long, antero-posteriorly compressed neck and a robust, curved shaft with a pronounced gluteal line. A new cranium of Rudapithecus (= Dryopithecus brancoi), RUD-200 ("Gabi") were found in 1999 at Rudabánya. RUD-200 is the first Dryopithecus cranial specimen preserving large portions of the face and neurocranium with direct bone to bone contact. It shares the same great ape characters found in other Dryopithecus from Rudabánya and elsewhere in Europe (dental proportions, labiolingually thick incisors, compressed canines, elongated postcanines, no cingula, reduced premolar cusp heteromorphy, large brain, high root of zygomatic, no subarcuate fossa). It also shares African ape characters seen in other Dryopithecus specimens (laterally facing malar surface, stepped subnasal floor, mildly elongated subnasal clivus, elongated cranium, prominent entoglenoid, fused articular and tympanic temporal, subtle but distinct supraorbital torus, supratoral sulcus, projecting glabella, small but inferiorly placed frontal sinus widest at or below nasion in ethmoidal region and thin enamel with high dentine penetrance)

Fatigue stress resistance of some composite materials for dental fillings

The paper investigates fatigue stress resistance of some originally made composite materials based on Bis-GMA resin with fluoridated glass and YbF3. The material was used to fill in the cavities in teeth extracted for orthodontic reasons. For laboratory tests a mastication simulator was used. The tooth samples were placed in special holders with resin and exposed to cyclic mechanical loads (100 000 cycles) in order to assess their resistance to fatigue stress. The influence of repeatable mechanical loads on the teeth and the structure of the material were investigated. Additionally, the impact of cyclic loads on fluoride release from the composite materials was estimate

Υπολογισμός της μαγνονικής δομής ζωνών περιδικά δομημένων μαγνητικών υλικών με τη μέθοδο των επιπέδων κυμάτων

Στην εργασία αυτή μελετώνται οι σχέσεις διασποράς για τη διάδοση των κυμάτων σπιν σε διδιάστατες περιοδικές δομές μαγνητικών υλικών λύνοντας τη γραμμική εξίσωση κίνησης της μαγνήτισης Landau – Lifshitz για συγκεκριμένο ενεργό πεδίο που προκαλείται από διπολικές αλληλεπιδράσεις και αλληλεπιδράσεις ανταλλαγής. Παρατίθενται τα απαραίτητα στοιχεία για το χαρακτηρισμό της διάδοσης των κυμάτων σπιν και λύνεται η εξίσωση Landau – Lifshitz για μαγνητοστατικά κύματα σπιν. Εξάγονται οι εξισώσεις ιδιοτιμών και ιδιοανυσμάτων της μαγνήτισης λύνοντας την εξίσωση Landau – Lifshitz χρησιμοποιώντας ανάπτυξη σε επίπεδα κύματα και ανάλυση Fourier για δύο διαφορετικές περιοδικές δομές κυλίνδρων εμβαπτισμένων σε μαγνητικό μητρικό υλικόIn this thesis we study the dispersion relations for the propagation of spin waves in two - dimensional periodic structures of magnetic materials by solving the linearized Landau – Lifshitz equation of motion of the magnetization for an effective field caused by dipolar and exchange interactions. We provide an overview of the necessary ingredients to describe the propagation of spin waves and discuss the solution of the Landau – Lifshitz equation for magnetostatic spin waves. We consider two different periodic structures of cylinders embedded in a magnetic material and the magnetic dynamics are studied using a plane wave method. By expanding the spatial variation of the magnetization and the material properties into plane waves, the equation of motion is transformed into an algebraic system of equations and the magnetization is deduced from the solution of an eigenvalue proble