The position of the mental foramen in dentate and edentulous mandibles: clinical and surgical relevance

Background: The knowledge of the exact location of the mental foramen (MF) in dentate and edentulous mandibles is clinically important when constructing complete dentures, performing anaesthetic block of the lower-anterior teeth area and intervening in the MF nearby area. In edentulous mandibles, the bone resorption after teeth loss makes the mental nerve (MN) prone to damage due to the extreme location of the MF very close to the alveolar crest (AC). Chronic compression on the MN may result in pain in the area of MN distribution (ipsilateral face and cheek area) and numbness at the lower lip. The purpose of the current study is to evaluate the exact position of the MF, calculating the distances MF-superior border of the AC and MF-inferior border of the mandible (IBM) in dentate and edentulous mandibles. Materials and methods: One hundred and two (36 edentulous and 66 dentate) adult dry Greek mandibles were studied. Results: In 9 out of 36 edentulous mandibles (25%), the MF was found nearby the AC, while in 27 edentulous mandibles (75%), the MF was located at an average distance 6.4 mm from the AC and 12.6 mm from the IBM. In 38 out of 66 dentate mandibles (57.6%), the MF was located at an average distance 13.6 mm from the AC and 15.2 mm from the IBM. The dental status significantly affected (p = 0.001) the distances MF-AC and MF-IBM. Side symmetry was observed for both dentate and edentulous mandibles (p = 0.39 and p = 0.45). Conclusions: The MF is an important landmark and its location needs to be considered prior to dental implants placement in order to avoid the MN injury and related complications. The position of MF is altered in edentulous mandibles compared with the dentate ones. The MF is a symmetric structure in Greeks

THE HELLENIC NATIONAL TSUNAMI WARNING CENTER: RESEARCH, OPERATIONAL AND TRAINING ACTIVITIES

Το Εθνικό Κέντρο Προειδοποίησης για Τσουνάμι (ΕΚΠΤ) ιδρύθηκε στην Ελλάδα με νόμο, το Σεπτέμβριο του 2010, και λειτουργεί ως ιδιαίτερη μονάδα του Γεωδυναμικού Ινστιτούτο του Εθνικού Αστεροσκοπείου Αθηνών (ΕΑΑ-ΓΙ). Το κέντρο λειτουργεί σε 24/7 βάση και σκοπό έχει την παρακολούθηση της εκδήλωσης τσουνάμι στην Ελλάδα και την ανατολική Μεσόγειο, παρέχοντας μηνύματα προειδοποίησης στη Γενική Γραμματεία Πολιτικής Προστασίας. Από τον Αύγουστο του 2012, το ΕΚΠΤ ενεργεί ως Υποψήφιος Πάροχος Υπηρεσιών Τσουνάμι (CTSP) στο πλαίσιο του Σύστηματος Προειδοποίησης για Τσουνάμι στο Βορειοανατολικό Ατλαντικό, τη Μεσόγειο και τις γειτονικές θάλασσες (NEAMTWS) της IOC/UNESCO. Η λειτουργία του ΕΚΠΤ βασίζεται στο εθνικό δίκτυο σεισμογράφων και παλιρροιογράφων του ΕΑΑ και αξιοποιεί ποικιλία βάσεων δεδομένων, αλγορίθμων και υπολογιστικών εργαλείων. Η συνεργασία με κορυφαία ερευνητικά ιδρύματα, στο πλαίσιο σημαντικών ερευνητικών έργων χρηματοδοτούμενων από την ΕΕ, ενισχύει την επιστημονική κατάρτιση του κέντρου. H εκπαίδευση του προσωπικού που συμμετέχει στην 24-ωρη λειτουργία του κέντρου, διεξάγεται συνεχώς μέσω δοκιμών και ασκήσεων, προκειμένου να διατηρηθεί ένα υψηλό επίπεδο ετοιμότητας και ανταπόκρισης σε περίπτωση έκτακτης ανάγκης. Από τον Αύγουστο του 2012 το ΕΚΠΤ ως επιχειρησιακό κέντρο έχει εκδώσει έγκαιρα 14 μηνύματα προειδοποίησης για πιθανά τσουνάμι μετά από ισχυρούς σεισμούς.The Hellenic National Tsunami Warning Center (HL-NTWC), which is a unit of the Institute of Geodynamics of the National Observatory of Athens (NOA-IG), was officially established in Greece by law in September 2010. It operates a 24/7 tsunami monitoring service for Greece and the eastern Mediterranean Sea, providing warning messages to the General Secretariat for Civil Protection in Greece. Since August 2012, HL-NTWC acts as Candidate Tsunami Service Provider (CTSP) in the framework of the North-Eastern Atlantic, the Mediterranean and connected seas Tsunami Warning System (NEAMTWS) of the IOC/UNESCO providing tsunami messages to a large number of subscribers. The HL-NTWC function is based on the national seismograph and tide gauge networks of NOA-IG and incorporates several data bases, algorithms and computational tools. Collaboration with top class research institutions in the framework of important EC funded tsunami research projects strengthens the scientific background of the center. Tests, exercises and training of the duty officers involved in the 24/7 operation of the HL-NTWC are carried on constantly, in order to maintain a high level of readiness and response in case of emergency. In its operational life since August 2012 the HL-NTWC has timely issued tsunami warning messages for 14 potentially tsunamigenic earthquake events

Segmented Hellenic slab rollback driving Aegean deformation and seismicity

The NE dipping slab of the Hellenic subduction is imaged in unprecedented detail using teleseismic receiver function analysis on a dense 2-D seismic array. Mapping of slab geometry for over 300 km along strike and down to 100 km depth reveals a segmentation into dipping panels by along-dip faults. Resolved intermediate-depth seismicity commonly attributed to dehydration embrittlement is shown to be clustered along these faults. Large earthquakes occurrence within the upper and lower plate and at the interplate megathrust boundary show a striking correlation with the slab faults suggesting high mechanical coupling between the two plates. Our results imply that the general slab rollback occurs here in a differential piecewise manner imposing its specific stress and deformation pattern onto the overriding Aegean plate

TheoryGuru: A Mathematica Package to Apply Quantifier Elimination Technology to Economics

We consider the use of Quantifier Elimination (QE) technology for automated reasoning in economics. There is a great body of work considering QE applications in science and engineering but we demonstrate here that it also has use in the social sciences. We explain how many suggested theorems in economics could either be proven, or even have their hypotheses shown to be inconsistent, automatically via QE. However, economists who this technology could benefit are usually unfamiliar with QE, and the use of mathematical software generally. This motivated the development of a Mathematica Package TheoryGuru, whose purpose is to lower the costs of applying QE to economics. We describe the package's functionality and give examples of its use.Comment: To appear in Proc ICMS 201

Slab segmentation controls the interplate slip motion in the SW Hellenic subduction: New insight from the 2008Mw 6.8 Methoni interplate earthquake

We present an integrated approach of the seismic structure and activity along the offshore SW Hellenic subduction from combined observations of marine and land seismic stations. Our imaging of the slab top topography from teleseismic receiver function analysis at ocean bottom seismometers supports a trenchward continuation of the along-dip slab faults beneath the Peloponnesus. We further show that their morphostructural control accounts for the backstepping of the thrust contact of the Mediterranean Ridge accretionary wedge over the upper plate. Local seismic activity offshore SW Peloponnesus constrained by ocean bottom seismometer observations reveals a correlation with specific features of the forearc: the Matapan Troughs. We study the Mw6.8 14.02.2008 interplate earthquake offshore SW Peloponnesus and show that its nucleation, rupture zone, and aftershocks sequence are confined to one slab panel between two adjacent along-dip faults and are thus controlled by not only the offshore slab top segmentation but also the upper plate sea-bottom morphology

Virulence factors and antibiotic susceptibility in enterococci isolated from oral mucosal and deep infections

This study evaluates the presence of virulence factors and antibiotic susceptibility among enterococcal isolates from oral mucosal and deep infections. Forty-three enterococcal strains from oral mucosal lesions and 18 from deep infections were isolated from 830 samples that were sent during 2 years to Oral Microbiology, University of Gothenburg, for analysis. The 61 strains were identified by 16S rDNA, and characterized by the presence of the virulence genes efa A (endocarditis gene), gel E (gelatinase gene), ace (collagen binding antigen gene), asa (aggregation substance gene), cyl A (cytolysin activator gene) and esp (surface adhesin gene), tested for the production of bacteriocins and presence of plasmids. MIC determination was performed using the E-test method against the most commonly used antibiotics in dentistry, for example, penicillin V, amoxicillin and clindamycin. Vancomycin was included in order to detect vancomycin-resistant enterococci (VRE) strains. Sixty strains were identified as Enterococcus faecalis and one as Enterococcus faecium. All the virulence genes were detected in more than 93.3% (efa A and esp) of the E. faecalis strains, while the presence of phenotypic characteristics was much lower (gelatinase 10% and hemolysin 16.7%). Forty-six strains produced bacteriocins and one to six plasmids were detected in half of the isolates. Enterococcal strains from oral infections had a high virulence capacity, showed bacteriocin production and had numerous plasmids. They were generally susceptible to ampicillins but were resistant to clindamycin, commonly used in dentistry, and no VRE-strain was found