A Concurrent Language with a Uniform Treatment of Regions and Locks

A challenge for programming language research is to design and implement multi-threaded low-level languages providing static guarantees for memory safety and freedom from data races. Towards this goal, we present a concurrent language employing safe region-based memory management and hierarchical locking of regions. Both regions and locks are treated uniformly, and the language supports ownership transfer, early deallocation of regions and early release of locks in a safe manner

Συστήματα Διαχείρισης Ποιότητας – Σύγκριση & Αξιολόγηση

Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Τεχνο-Οικονομικά Συστήματα (ΜΒΑ)

The gills and skin microbiota of five pelagic fish species from the Atlantic Ocean

The gills and skin microbiota and microbiome of wild fish remain far more under-investigated compared to that of farmed fish species, despite that these animal-microbe interactions hold the same ecophysiological roles in both cases. In this study, the gills and skin bacterial microbiota profiles and their presumptive bacterial metabolisms were investigated in five open-sea fishes: bullet tuna (Auxis sp.), common dolphinfish (Coryphaena hippurus), Atlantic little tunny (Euthynnus alletteratus), Atlantic bonito (Sarda sarda) and Atlantic white marlin (Kajikia albida). Gills and skin tissues were collected from two to three individuals per species, from specimens caught by recreational trolling during summer of 2019, and their bacterial 16S rRNA gene diversity was analysed by high-throughput sequencing. The gills bacterial communities among the five species were clearly different but not the skin bacterial microbiota. The dominant operational taxonomic units belonged to the Moraxellaceae, Pseudomonadaceae, Rhodobacteraceae, Staphylococcaceae and Vibrionaceae families. Despite the differences in taxonomic composition, the presumptive bacterial metabolisms between the gills and skin of the five fishes investigated here were ≥ 94% similar and were dominated by basic metabolism, most likely reflecting the continuous exposure of these tissues in the surrounding seawater

Colour duplex sonography of temporal arteries before decision for biopsy: a prospective study in 55 patients with suspected giant cell arteritis

Although a temporal artery biopsy is the gold standard for the diagnosis of giant cell arteritis (GCA), there is considerable evidence that characteristic signs demonstrated by colour duplex sonography (CDS) of the temporal arteries may be of diagnostic importance. We aimed to test the hypothesis that CDS can replace biopsy in the algorithm for the approach to diagnose GCA. Bilateral CDS was performed in consecutive patients older than 50 years with clinically suspected GCA, as well as in 15 age- and gender-matched control subjects with diabetes mellitus and/or stroke and 15 healthy subjects, to assess flow parameters and the possible presence of a dark halo around the arterial lumen. Unilateral temporal artery biopsy was then performed in patients with suspected GCA, which was directed to a particular arterial segment in case a halo was detected in CDS. Final diagnoses, after completion of a 3-month follow-up in 55 patients, included GCA (n = 22), polymyalgia rheumatica (n = 12), polyarteritis nodosa, Wegener's, and Adamantiades-Behçet's diseases (n = 3), and neoplastic (n = 8) and infectious diseases (n = 10). A dark halo of variable size (0.7–2.0 mm) around the vessel lumen was evident at baseline CDS in 21 patients (in 12 and 9 uni- or bilaterally, respectively) but in none of the controls. The presence of unilateral halo alone yielded 82% sensitivity and 91% specificity for GCA, whereas the specificity reached 100% when halos were found bilaterally. Blood-flow abnormal parameters (temporal artery diameter, peak systolic blood-flow velocities, stenoses, occlusions) were common in GCA and non-GCA patients, as well as in healthy and atherosclerotic disease-control, elderly subjects. At follow-up CDS examinations performed at 2 and 4 weeks after initiation of corticosteroid treatment for GCA, halos disappeared in all 18 patients (9 and 9, respectively). We conclude that CDS, an inexpensive, non-invasive, and easy-to-perform method, allows a directional biopsy that has an increased probability to confirm the clinical diagnosis. Biopsy is not necessary in a substantial proportion of patients in whom bilateral halo signs can be found by CDS

A Type System for Unstructured Locking that Guarantees Deadlock Freedom without Imposing a Lock Ordering

Deadlocks occur in concurrent programs as a consequence of cyclic resource acquisition between threads. In this paper we present a novel type system that guarantees deadlock freedom for a language with references, unstructured locking primitives, and locks which are implicitly associated with references. The proposed type system does not impose a strict lock acquisition order and thus increases programming language expressiveness.Comment: In Proceedings PLACES 2010, arXiv:1110.385

Ανάπτυξη portal και απεικόνιση χωρικών σημειακών μετρήσεων σε περιβάλλον Google Maps με χρήση τεχνολογιών ανοικτού κώδικα

64 σ.Αντικείμενο της διπλωματικής είναι η ανάπτυξη ενός portal που αφορά στην ιστοσελίδα του Κέντρου Εκτίμησης Φυσικών Κινδύνων και Προληπτικού Σχεδιασμού ΕΜΠ, και η ανάπτυξη μιας δικτυακής εφαρμογής για την απεικόνιση περιβαλλοντικών μετρήσεων στα χαρτογραφικά υπόβαθρα που διαθέτει η google. Για την υλοποίηση χρησιμοποιούνται ελεύθερο λογισμικό καθώς και δωρεάν υπηρεσίες που δοσπόζουν αυτή την περίοδο στο διαδίκτυο. Γίνεται χρήση ελεύθερου λογισμικού για την βάση δεδομένων, για την διαχείριση περιεχομένου της ιστοσελίδας και για την απεικόνιση των μετρήσεων σε γραφήματα (MySQL, Joomla! cms και Simile Timeplot αντίστοιχα), ενώ χρησιμοποιείται η υπηρεσία google maps api για την αλληλεπίδραση με τα υπόβαθρα google maps. Για τον προγραμματισμό χρησιμοποιούνται οι γλώσσες php, javascript, ενώ αξιοποιείται η τεχνολογία ασύγχρονης μεταφοράς δεδομένων XML για την απεικόνιση των δεδομένων από τη MySQL. Η ανεξαρτησία της εφαμογής από το είδος την μετρήσεων που μπορεί να διαχειριστεί, επεκτείνει τη δυνατότητα αξιοποίησής της, πέρα από την απεικόνιση περιβαλλοντικών μετρήσεων.The objective of this Thesis is the creation of the Centre’s for the Assessment of Natural Hazards and Proactive Planning, portal as well as the development of a web application to display environmental measurements in cartographic frameworks that Google provides. Free software and free web services are used for the development. MySQl for the DataBase, Joomla! for the content management, Simele TimePlot for the timelines and google maps api. The application is written in php and javascript using the Ajax tecnology for the asynchronous dislay of the data. The independence from the kind of measurements, extends the applications usability beyond the representation of environmental data.Κωνσταντίνος Π. Παπασπύρο

Application development on mobile terminals for indoor navigation

234 σ.Ο ακριβής εντοπισμός θέσης σε εσωτερικούς χώρους και η πλοήγηση σε αυτούς αποτελεί τα τελευταία χρόνια ένα δημοφιλή και εξελισσόμενο κλάδο των ασύρματων τηλεπικοινωνιών, με μεγάλη ποικιλία εφαρμογών στους τομείς της βιομηχανίας, της υγείας, της ασφάλειας, αλλά και σε πολλούς άλλους τομείς της καθημερινής ανθρώπινης δραστηριότητας. Η περιορισμένη έκταση των εσωτερικών χώρων, αλλά και οι ιδιαιτέρως απρόβλεπτες και δυσμενείς συνθήκες διάδοσης των σημάτων σε αυτούς, οι οποίες καθιστούν τα γνωστά συστήματα εντοπισμού θέσης εξωτερικών χώρων ανεπαρκή για εντοπισμό σε εσωτερικούς χώρους, αποτελούν πρόκληση για τους σχεδιαστές. Έχει προταθεί ένας μεγάλος αριθμός συστημάτων εντοπισμού θέσης εσωτερικού χώρου και πλοήγησης, καθώς και ένα μεγάλο εύρος τεχνολογιών και μεθόδων εντοπισμού που αφορούν αυτά. Σημαντικός παράγοντας για την ανάπτυξη τέτοιων συστημάτων ήταν η εμφάνιση έξυπνων συσκευών κινητής τηλεφωνίας, γνωστών και ως smartphones και ειδικότερα καινοτόμων λειτουργικών συστημάτων όπως το Android. Το Android είναι ένα λογισμικό ανοιχτού κώδικα, το οποίο υποστηρίζεται πλήρως από την εταιρεία Google. Στο λογισμικό αυτό μπορεί οποιοσδήποτε χρήστης να αναπτύξει τη δική του εφαρμογή σύμφωνα με τις ανάγκες αλλά και τις επιθυμίες του. Έτσι, στα πλαίσια της συγκεκριμένης διπλωματικής εργασίας αναπτύχθηκε σε λειτουργικό Android OS ένα σύστημα πλοήγησης σε εσωτερικό χώρο. Στο σύστημα αυτό, θεωρείται δεδομένη η θέση του χρήστη, ο οποίος με τη χρήση κατάλληλων αλγορίθμων δρομολόγησης μπορεί να οδηγηθεί στον προορισμό του. Επίσης, παρέχονται χρήσιμες πληροφορίες στον χρήστη είτε κατά την διάρκεια της πλοήγησης είτε κατά την επεξεργασία της εφαρμογής. Η διπλωματική εργασία χωρίζεται σε 6 κεφάλαια. Στο πρώτο κεφάλαιο πραγματοποιείται μία βιβλιογραφική επισκόπηση των γνωστών μεθόδων και συστημάτων εντοπισμού θέσης σε εξωτερικούς και εσωτερικούς χώρους. Στο δεύτερο κεφάλαιο παρουσιάζονται οι αλγόριθμοι εύρεσης ελάχιστης απόστασης. Στο τρίτο κεφάλαιο, περιγράφονται τα χαρακτηριστικά, οι δυνατότητες, οι εκδόσεις και άλλες χρήσιμες πληροφορίες του λειτουργικού Android OS. Το τέταρτο κεφάλαιο ασχολείται με την περιγραφή των λειτουργιών της εφαρμογής και δίνονται κάποια παραδείγματα τρεξίματος του αλγορίθμου δρομολόγησης. Στο πέμπτο κεφάλαιο δίνεται μια αναλυτική περιγραφή του συστήματος που αναπτύχθηκε. Τέλος, στο έκτο κεφάλαιο, παρουσιάζονται πιθανές μελλοντικές βελτιστοποιήσεις και επεκτάσεις της εφαρμογής. Στο παράρτημα μπορεί κανείς τα βασικά τμήματα του κώδικα της εφαρμογής.In the past few years, accurate indoor positioning and navigation constitute one of the most popular and evolving applications of wireless telecommunications, with a great variety of commercial applications in the sectors of industry, health, safety, but also in a lot of other sectors of human activities. The limited extent of indoor spaces, but also especially the unpredicted and unfavorable propagation conditions of signals make the well-known outdoor positioning systems insufficient for indoor positioning. This is a technical challenge for the system designers. A large number of indoor positioning and navigation systems have been proposed, as well as a great range of technologies and methods of localization that concern these. An important factor for the development of such systems was the emergence of intelligent mobile devices known as smartphones and especially innovative operating systems such as Android. The Android is an open source software, which is fully supported by the company Google. In this software any user is able to develop his own application in accordance with his needs and desires. The scope of this diploma thesis is to develop an indoor navigation application for Android terminals. This application exploits the existing positioning systems and navigates the user to his destination. Also, vocal messages are generated while using the application. This diploma thesis consists of 6 chapters. The first chapter contains a literature review of outdoor and indoor positioning methods and systems. The second chapter presents a review of the existing routing algorithms. Chapter 3 includes the characteristics, the capabilities, the versions and other useful information about Android OS. The fourth chapter describes in detail the developed application and presents some generated examples of the routing algorithm. The fifth chapter contains a thorough description of the exploited routing algorithm. Future expansions and optimizations of the application are presented in chapter 6. Finally, in the appendix one can find the basic parts of the programming code.Κωνσταντίνος Δ. Παπασπύρο

Incidence and Risk Factors for Blood Stream Infection in Mechanically Ventilated COVID-19 Patients

It is widely known that blood stream infections (BSIs) in critically ill patients may affect mortality, length of stay, or the duration of mechanical ventilation. There is scarce data regarding blood stream infections in mechanically ventilated COVID-19 patients. Preliminary studies report that the number of secondary infections in COVID-9 patients may be higher. This retrospective analysis was conducted to determine the incidence of BSI. Furthermore, risk factors, mortality, and other outcomes were analyzed. The setting was an Intensive Care Unit (ICU) at a University Hospital. Patients suffering from SARS-CoV-2 infection and requiring mechanical ventilation (MV) for >48 h were eligible. The characteristics of patients who presented BSI were compared with those of patients who did not present BSI. Eighty-four patients were included. The incidence of BSI was 57%. In most cases, multidrug-resistant pathogens were isolated. Dyslipidemia was more frequent in the BSI group (p < 0.05). Moreover, BSI-group patients had a longer ICU stay and a longer duration of both mechanical ventilation and sedation (p < 0.05). Deaths were not statistically different between the two groups (73% for BSI and 56% for the non-BSI group, p > 0.05). Compared with non-survivors, survivors had lower baseline APACHE II and SOFA scores, lower D-dimers levels, a higher baseline compliance of the respiratory system, and less frequent heart failure. They received anakinra less frequently and appropriate therapy more often (p < 0.05). The independent risk factor for mortality was the APACHE II score [1.232 (1.017 to 1.493), p = 0.033]

Hypoxia-Inducible Factor 2α Mutation-Related Paragangliomas Classify as Discrete Pseudohypoxic Subcluster

Recently, activating mutations of the hypoxia-inducible factor 2α gene (HIF2A/EPAS1) have been recognized to predispose to multiple paragangliomas (PGLs) and duodenal somatostatinomas associated with polycythemia, and ocular abnormalities. Previously, mutations in the SDHA/B/C/D, SDHAF2, VHL, FH, PHD1, and PHD2 genes have been associated with HIF activation and the development of pseudohypoxic (cluster-1) PGLs. These tumors overlap in terms of tumor location, syndromic presentation, and noradrenergic phenotype to a certain extent. However, they also differ especially by clinical outcome and by presence of other tumors or abnormalities. In the present study, we aimed to establish additional molecular differences between HIF2A and non-HIF2A pseudohypoxic PGLs. RNA expression patterns of HIF2A PGLs (n = 6) from 2 patients were compared with normal adrenal medullas (n = 8) and other hereditary pseudohypoxic PGLs (VHL: n = 13, SDHB: n = 15, and SDHD: n = 14). Unsupervised hierarchical clustering showed that HIF2A PGLs made up a separate cluster from other pseudohypoxic PGLs. Significance analysis of microarray yielded 875 differentially expressed genes between HIF2A and other pseudohypoxic PGLs after normalization to adrenal medulla (false discovery rate 0.01). Prediction analysis of microarray allowed correct classification of all HIF2A samples based on as little as three genes (TRHDE, LRRC63, IGSF10; error rate: 0.02). Genes with the highest expression difference between normal medulla and HIF2A PGLs were selected for confirmatory quantitative reverse transcriptase polymerase chain reaction. In conclusion, HIF2A PGLs show a characteristic expression signature that separates them from non-HIF2A pseudohypoxic PGLs. Unexpectedly, the most significantly differentially expressed genes have not been previously described as HIF target genes