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Local symmetry dynamics in one-dimensional aperiodic lattices: a numerical study
Get PDFA unifying description of lattice potentials generated by aperiodic one-dimensional sequences is proposed in terms of their local reflection or parity symmetry properties. We demonstrate that the ranges and axes of local reflection symmetry possess characteristic distributional and dynamical properties which can be determined for every aperiodic binary lattice. A striking aspect of such a property is given by the return maps of sequential spacings of local symmetry axes, which typically traverse few-point symmetry orbits. This local symmetry dynamics allows for a classification of inherently different aperiodic lattices according to fundamental symmetry principles. Illustrating the local symmetry distributional and dynamical properties for several representative binary lattices, we further show that the renormalized axis spacing sequences follow precisely the particular type of underlying aperiodic order. Our analysis thus reveals that the long-range order of aperiodic lattices is characterized in a compellingly simple way by its local symmetry dynamics
Μελέτη της έκφρασης της ανθρώπινης ριβονουκλεάσης κ και πιθανών ισομορφών της σε διάφορους ιστούς
Get PDFΣτόχος της παρούσας διατριβής ήταν η μελέτη της έκφρασης της ανθρώπινης ριβονουκλεάσης κ και πιθανών ισομορφών της σε διάφορους ιστούς. Στα πλαίσια της έρευνας αυτής απομονώθηκε και μελετήθηκε μια νέα εναλλακτική ισομορφή, η ανθρώπινη ριβονουκλεάση κ-02
Molecular dynamics simulations and MM-PBSA binding free energy estimation in GK241-sPLA2 GIIA complex
No full textΘαλής – ΤΕΙ Καβάλας - Nanocapillary: Αναφορά Υάλων - MIS 375233
Get PDFΗ παρούσα τελική αναφορά των υάλων αφορά την παρουσίαση του χαρακτηρισμού των ύαλων στα πλαίσια του έργου Nanocapillary Θαλής του ΤΕΙ Ανατολικής Μακεδονίας και Θράκης και συγκεκριμένα του vycor 7930 και του CPG – 80.
Κατά το προαναφερθέν χρονικό διάστημα μελετήθηκαν και χαρακτηρίστηκαν δύο από τις σημαντικότερες κατηγορίες υάλων. Η μία αποτελεί τις πορώδεις υάλους Vycor και συγκεκριμένα του Vycor 7930 και η δεύτερη τς Υάλους Ελεγχόμενου Μεγέθους Πόρων (Control Porous Glasses – CPG). Η χρήση των πορωδών υλικών είναι εξόχως σημαντική για ένα πολύ μεγάλο φάσμα εφαρμογών. Τόσο το Vycor όσο και το CPG μπορούν να χρησιμοποιηθούν στην βιομηχανία ή και την ιατρική. Μερικές από τις εφαρμογές τους είναι η κατάλυση, η τεχνολογία μεμβρανών, ο διαχωρισμός αερίων, η τεχνολογία πετρελαίου κ.α. Ο πλήρης χαρακτηρισμός τους θα δώσει την γνώση, για περαιτέρω χρησιμοποίηση τους. Ο χαρακτηρισμός των πορωδών υλικών απαιτεί την συλλογή μιας σειράς μετρήσεων που αφορούν το πορώδες, την ειδική επιφάνεια, την κατανομή του μεγέθους, το σχήμα, την διάταξη και την επιφανειακή γεωμετρία των πόρων. Ο καθορισμός όλων αυτών των παραμέτρων απαιτεί την εφαρμογή τεχνικών όπως η ποροσιμετρία αζώτου και υδραργύρου, η ηλεκτρονική μικροσκοπία (SEM), η περίθλαση των ακτίνων – Χ (XRD) και η μικρογωνιακή σκέδαση ακτίνων – Χ (SAXS). Τέλος για τον πληρέστερο χαρακτηρισμό τους και κυρίως για την μελέτη της αλληλεπίδρασης του πορώδους με αέρια, υλοποιήθηκε πείραμα ρόφησης διβρομομεθανίου σε vycor
Globigerinoides ruber (w) morpho-specific response on past SSS and SST changes inferred from stable isotopes and geochemical proxies (Mg/Ca, Ba/Ca): A Gulf of Mexico Perspective
Get PDFBioconcentration of Cd and Ni in various tissues of two marine bivalves living in different habitats and exposed to heavily polluted seawater
Get PDFTwo marine bivalves, Mytilus galloprovincialis and Callista chione, were exposed to various concentrations of cadmium and nickel (0.5, 1.0, 2.5 and 20 ppm), for 20 days, plus 10 days’ depuration period, in a laboratory experiment. Animals from each experimental condition were dissected and the bioaccumulation and distribution of Cd and Ni were determined in their gills, mantles and remaining bodies. The concentrations of Fe and Zn were also measured. Heavy metal tolerance, bioconcentration and distribution of heavy metals in tissues were considerably different in M. galloprovincialis and C. chione: (i) both animals were tolerant to Ni pollution, even at the highest concentration used; (ii) C. chione was more tolerant to Cd; (iii) M. galloprovincialis was a better Cd and Ni accumulator, with the exception of the highest Cd concentration tested, where C. chione accumulated more Cd; (iv) Fe and Zn levels were much more affected in M. galloprovincialis; (v) in general, accumulation and distribution of Ni and Cd in the tissues were metal-, species- and time of exposure- dependent; (vi) significant amounts of heavy metals remained in the tissues after 10 days’ depuration. Our results support a hypothesis for a two competing processes mechanism for metal accumulation and detoxification
Parallel patterns and trends in functional structures in extinct island mammals
Get PDFEndemic mammalian species on islands are generally known to have followed a different evolutionary pathway than their mainland relatives. General patterns, such as body size trends, have been described regularly. However, most island mammal species are unique and each of them is adapted to a specific local niche as part of an equally specific ecological assemblage. Therefore, comparing island species across taxa, islands and time is inherently
dangerous without understanding the adaptational value of the studied feature in the compared taxa and without taking the ecological setting of the taxa into account. In this contribution, general and recurring patterns are described per taxon. Some features, like body mass change and sturdy limbs, are relatively general, whereas most features, like bone fusions and change of orbital axis, occur only in a very few taxa. Some features are even contradictory, such as brain size and degree of hypsodonty, with each taxon having its own particular design. In conclusion, general patterns are more often than not just trends and need to be applied with caution
