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Reducing the risk of pathogen transmission to transfusion recipients is one of the great concerns in transfusion medicine. Important among the measures suggested to minimize pathogen transmission is pathogen reduction technology (PRT) systems. The Mirasol PRT System for platelets and plasma uses riboflavin and UV light to inhibit both pathogen and white blood cell replication. Pathogen inactivation may accelerate or induce lesions, potentially accounting for reduced viability. The PRT-treated platelets show signs of increased cellular activation, increased metabolism and reduced hemostatic capacity. The purpose of the study was to investigate the effect of PRT on the hemostatic capacity of platelets. Untreated platelets and PRT-treated platelets derived from ten apheresis platelet concentrates (PCs). PCs were divided into equally leading to twenty platelet concentrates that were stored in plasma. All PCs, were evaluated in vitro on days 1, 3, and 5 after collection, for metabolic properties, hemostatic properties, functionality and procoagulant activity. We observed that PRT adversely affected the metabolic and hemostatic profile of platelets in a time-dependent manner. PRT-treated platelets also showed increased activation and procoagulant activity particularly at the end of storage. Thus, PRT led to exhaustion of the hemostatic process especially at the end of the storage time. Well-designed clinical studies are needed to determine whether this in vitro reduced platelet functionality after PRT is reflected in vivo.

Μια από τις μεγαλύτερες προκλήσεις που έχει να αντιμετωπίσει η σύγχρονη ιατρική των μεταγγίσεων, είναι ο περιορισμός του κινδύνου μετάδοσης παθογόνων κατά τη διαδικασία της μετάγγισης. Ανάμεσα στα μέτρα που προτείνονται προκειμένου να επιτευχθεί κάτι τέτοιο, κυρίαρχη θέση κατέχουν τα συστήματα αδρανοποίησης (PRT). Η τεχνολογία Mirasol εφαρμόζεται στην αδρανοποίηση πλάσματος και αιμοπεταλίων όπου η ριβοφλαβίνη σε συνδυασμό με υπεριώδη ακτινοβολία αναστέλλει τον πολλαπλασιασμό των παθογόνων και των λευκών αιμοσφαιρίων. Η διαδικασία της αδρανοποίησης πιθανόν επιταχύνει ή δημιουργεί αλλοιώσεις που ενδεχομένως ευθύνονται για τη μειωμένη βιωσιμότητα των αιμοπεταλίων. Τα επεξεργασμένα αιμοπετάλια παρουσιάζουν ενδείξεις αυξημένης κυτταρικής δραστηριότητας, αύξηση του μεταβολισμού τους και μεταβολές της αιμοστατικής τους ικανότητας. Σκοπός της μελέτης ήταν η διερεύνηση της επίδρασης της αδρανοποίησης στην αιμοστατική ικανότητα των αιμοπεταλίων. Δέκα ασκοί αιμοπεταλίων αφαίρεσης χωρίστηκαν σε ισομεγέθη μερίσματα προκύπτοντας συνολικά είκοσι ασκοί. Από αυτούς οι μισοί αδρανοποιήθηκαν με το σύστημα Mirasol και οι άλλοι μισοί παράμειναν χωρίς επεξεργασία ως μάρτυρες. Τα αιμοπετάλια, αδρανοποιημένα και μη, αξιολογήθηκαν in vitro τις ημέρες 1, 3 και 5 μετά τη συλλογή για μεταβολικές και αιμοστατικές παραμέτρους, λειτουργικότητα και προπηκτική δραστηριότητα. Διαπιστώσαμε ότι η αδρανοποίηση επέδρασε δυσμενώς στο μεταβολικό και αιμοστατικό προφίλ των αιμοπεταλίων με χρονοεξαρτώμενο τρόπο. Τα αδρανοποιημένα αιμοπετάλια εμφάνισαν επίσης αυξημένη ενεργοποίηση και αυξημένη προπηκτική δραστηριότητα ιδιαίτερα στο τέλος της αποθηκευτικής ζωής. Η αδρανοποίηση επομένως οδήγησε σε σε εξάντληση της αιμοστατικής διαδικασίας ειδικά στο τέλος του αποθηκευτικού χρόνου. Είναι απαραίτητη η διενέργεια καλά σχεδιασμένων κλινικών μελετών προκειμένου να διαπιστωθεί αν αυτή η in vitro μειωμένη λειτουργικότητα αντανακλάται και in vivo. Reducing the risk of pathogen transmission to transfusion recipients is one of the great concerns in transfusion medicine. Important among the measures suggested to minimize pathogen transmission is pathogen reduction technology (PRT) systems. The Mirasol PRT System for platelets and plasma uses riboflavin and UV light to inhibit both pathogen and white blood cell replication. Pathogen inactivation may accelerate or induce lesions, potentially accounting for reduced viability. The PRT-treated platelets show signs of increased cellular activation, increased metabolism and reduced hemostatic capacity. The purpose of the study was to investigate the effect of PRT on the hemostatic capacity of platelets. Untreated platelets and PRT-treated platelets derived from ten apheresis platelet concentrates (PCs). PCs were divided into equally leading to twenty platelet concentrates that were stored in plasma. All PCs, were evaluated in vitro on days 1, 3, and 5 after collection, for metabolic properties, hemostatic properties, functionality and procoagulant activity. We observed that PRT adversely affected the metabolic and hemostatic profile of platelets in a time-dependent manner. PRT-treated platelets also showed increased activation and procoagulant activity particularly at the end of storage. Thus, PRT led to exhaustion of the hemostatic process especially at the end of the storage time. Well-designed clinical studies are needed to determine whether this in vitro reduced platelet functionality after PRT is reflected in vivo.

BACKGROUND: The haemostatic activity of platelet concentrates (PCs) treated with pathogen reduction technology (PRT) remains a subject of debate. Our aim was to investigate the effect of Mirasol PRT on the haemostatic properties of PCs stored in plasma. MATERIAL AND METHODS: Untreated and Mirasol-treated platelets stored in plasma and derived from ten split double-dose apheresis PCs were evaluated in vitro on days 1, 3 and 5 post collection for functionality, microparticle procoagulation activity (MPA), endogenous thrombin potential (ETP), and haemostatic profile using rotational thromboelastometry (ROTEM). RESULTS: P-selectin expression was significantly higher in Mirasol-treated platelets compared with untreated counterparts on days 3 and 5 (p=0.003 and p=0.002, respectively). Clot strength, as shown by EXTEM maximum clot firmness (MCF), was significantly lower in the Mirasol-treated platelets at all time points (days 1, 3, 5) than in untreated platelets (p=0.009, p

Social Media have a great impact on different aspects of people's lives and especially young age groups labelled as ‘digital natives’. Although researchers in the field of Computer-Assisted Language Learning (CALL) have unsurprisingly attempted to explore how both educational and non-educational social technologies (ST) could be employed to enhance language learning, the integration of social technologies in kindergarten-6th grade (K-6) education has received inadequate attention compared to research entailing teenagers or tertiary education students as the exploration of literature of the last two decades indicate. One reason for this is, most probably, the fact that children under the age of 13, are legally bound not to use social media. The present study sets out to explore students’ attitudes as well as benefits and challenges towards a synergy of age-appropriate, educational-oriented technologies in the context of a three-month intervention in a pre-intermediate level group of three 10-year-old male English as a Foreign Language (EFL) learners in Cyprus. Thematic analysis of students’ interviews, focus groups, observations and usage of age-appropriate technologies revealed students’ overall positive attitude towards these technologies, as well as challenges that need to be taken into consideration in the use of these technologies. The dissertation concludes with a discussion of findings and implications for further research. Completed

The timing of reproduction influences key evolutionary and ecological processes in wild populations. Variation in reproductive timing may be an especially important evolutionary driver in the marine environment, where the high mobility of many species and few physical barriers to migration provide limited opportunities for spatial divergence to arise. Using genomic data collected from spawning aggregations of Pacific herring (Clupea pallasii) across 1600 km of coastline, we show that reproductive timing drives population structure in these pelagic fish. Within a specific spawning season, we observed isolation by distance, indicating that gene flow is limited over our study area. These results emphasize the importance of considering both seasonal and spatial variation in spawning when delineating management units for herring. On several chromosomes, we detected linkage disequilibrium extending over Mb, suggesting the presence of chromosomal rearrangements. Spawning phenology was highly correlated with polymorphisms in several genes, in particular SYNE2, which influences the development of retinal photoreceptors in vertebrates. SYNE2 is likely within a chromosomal rearrangement in Pacific herring and is also associated with spawn timing in Atlantic herring (Clupea harengus). The observed genetic diversity likely underlies resource waves provided by spawning herring. Given the ecological, economic and cultural significance of herring, our results support that conserving intraspecific genetic diversity is important for maintaining current and future ecosystem processes.

The timing of reproduction influences key evolutionary and ecological processes in wild populations. Variation in reproductive timing may be an especially important evolutionary driver in the marine environment, where the high mobility of many species and few physical barriers to migration provide limited opportunities for spatial divergence to arise. Using genomic data collected from spawning aggregations of Pacific herring (Clupea pallasii) across 1600 km of coastline, we show that reproductive timing drives population structure in these pelagic fish. Within a specific spawning season, we observed isolation by distance, indicating that gene flow is limited over our study area. These results emphasize the importance of considering both seasonal and spatial variation in spawning when delineating management units for herring. On several chromosomes, we detected linkage disequilibrium extending over Mb, suggesting the presence of chromosomal rearrangements. Spawning phenology was highly correlated with polymorphisms in several genes, in particular SYNE2, which influences the development of retinal photoreceptors in vertebrates. SYNE2 is likely within a chromosomal rearrangement in Pacific herring and is also associated with spawn timing in Atlantic herring (Clupea harengus). The observed genetic diversity likely underlies resource waves provided by spawning herring. Given the ecological, economic and cultural significance of herring, our results support that conserving intraspecific genetic diversity is important for maintaining current and future ecosystem processes.

Περίληψη: Ο ανθρώπινος εγκέφαλος, ως ένα από τα πολυπλοκότερα βιολογικά συστήματα και αδιάσπαστο κομμάτι των καθημερινών μας πράξεων, έχει αποτελέσει, τις τελευταίες δεκαετίες, αντικείμενο μελέτης για την κατανόηση βασικών λειτουργιών του και, πιο συγκεκριμένα, τον εντοπισμό θεμελιωδών δυσλειτουργιών και διαταραχών αυτού. Για το λόγο αυτό, πολλά είναι εκείνα τα συστήματα που έχουν εφευρεθεί για την χωρική και χρονική απεικόνιση της δραστηριότητας του ανθρωπίνου εγκεφάλου. Η Μαγνητοεγκεφαλογραφία (ΜΕΓ) αποτελεί μία μη - επεμβατική νευροαπεικονιστική μέθοδο για την ανίχνευση της χωρικής πληροφορίας του εγκεφάλου μέσω της καταγραφής του μαγνητικού πεδίου, το οποίο παράγεται από την ηλεκτρική εγκεφαλική δραστηριότητα. Στην παρούσα διπλωματική εργασία μελετώνται οι ΜΕΓ καταγραφές παιδιών με αναγνωστικές δυσκολίες (Reading Difficulties Group - RD) και παιδιών χωρίς εγκεφαλικές διαταραχές (Non Impaired Group - NI). Με σκοπό την ανίχνευση και τον περιορισμό της μη – εγκεφαλικής δραστηριότητας γίνεται χρήση της μεθόδου των Ανεξάρτητων Συνιστωσών (Independent Component Analysis - ICA). Ως αποτέλεσμα της συγκεκριμένης μεθόδου είναι η εξαγωγή των στατιστικά ανεξάρτητων συνιστωσών (Independent Components – ICs), περιλαμβάνοντας είτε εγκεφαλική είτε μη - εγκεφαλική δραστηριότητα. Στην συνέχεια, δομείται ο γράφος λειτουργικής συνδεσιμότητας (Functional Connectivity Graph – FCG), μέσω της μετρικής καθυστέρησης φάσης (Phase Lag Index - PLI), η οποία αναπαριστά τον συγχρονισμό φάσης μεταξύ δύο σημάτων. Προκειμένου να εξασφαλιστεί η διατήρηση των σημαντικότερων συνδέσεων (significant links) μεταξύ των κόμβων του κάθε FCG, υπολογίζεται η μετρική της καθολικής αποδοτικότητας κόστους (Global Cost Efficiency - GCE). Εν συνεχεία, στο πεδίο μελέτης συμπεριλαμβάνεται ο υπολογισμός των Rich Club τοπολογιών, με στόχο την ανάδειξη κόμβων με υψηλό ποσοστό πληροφορίας και εκτιμώνται στατιστικές διαφορές πάνω στις τοπολογίες αυτών μεταξύ των δύο ομάδων. Οι στατιστικά σημαντικές διαφορές, που προέκυψαν μεταξύ των δύο υπό μελέτη ομάδων συγκεντρώνονται, κυρίως, στην πάνω από τον μετωπιαίο λοβό πλευρά και αριστερά πάνω από το βρεγματικό και κροταφικό λοβό. Αυτά τα στοιχεία έρχονται σε συμφωνία με προηγούμενες μελέτες, εφόσον στις συγκεκριμένες περιοχές εδράζονται τα κύρια κέντρα του λόγου. Επομένως, η χρήση ΜΕΓ και ο συνδυασμός συγχρονισμού φάσης και Rich Club τοπολογιών ίσως βοηθήσει μελλοντικά στην μη επεμβατική ανάδειξη δυσλειτουργιών και κατά συνέπεια στην διάγνωση αναγνωστικών δυσκολιών. Summarization: The human brain, as one of the most complex biological systems and an inseparable part of our daily actions, has been the object of study over the last few decades to understand its basic functions and, more specifically, to identify its fundamental dysfunctions and disorders. For this reason, there are many systems that have been invented for spatial and temporal imaging of human brain activity. Magnetoencephalography (MEG) is a non-invasive neuroimaging method for detecting spatial information of the brain by recording the magnetic field, generated by electrical activity of the brain. In this thesis are studied the MEG recordings, that were obtained from children with Reading Difficulties (RD Group) and from Non-Impaired children (NI Group). In order to detect and restrict non-cerebral activity, the Independent Component Analysis (ICA) is used. As a result of this method is the export of Independent Components (ICs), that represent cerebral or non-cerebral activity. After that the Functional Connectivity Graph (FCG) is built, through the Phase Lag Index (PLI), which represents the phase synchronization between two signals. In order to ensure the maintenance of the most significant links between the nodes of each FCG, the Global Cost Efficiency (GCE) is calculated. Moreover, in the field of study is also included the estimation of Rich Club topologies, aiming at the pointing out of nodes with high rate of information and the statistical differences on topologies between the two groups are estimated. The statistically significant differences, that occurred between the two groups are mainly appeared above the frontal lobe side and on the left side above the parietal and temporal lobe. These elements are in agreement with previous studies, since the main language centres are located in these areas. Therefore, the use of MEG, in combination with phase synchronization and Rich Club topologies may help in the future in non-invasive pointing out of disorders and consequently in the diagnosis of reading difficulties.