Displacement spectra and displacement modification factors, based on records from Greece

Elastic and inelastic displacement spectra (for periods up to 4.0 s) are derived, using a representative sample of acceleration records from Greece, carefully selected based on magnitude, distance and peak ground acceleration criteria, and grouped into three ground type categories according to the Eurocode 8 (EC8) provisions. The modification factor for the elastic design spectrum adopted in EC8 for accounting for damping is verified herein and is found to be satisfactory in the short to medium period range and less so in the long period range. The equivalent viscous damping ratio concept is also evaluated and is found to lead to underestimation of inelastic displacement spectra. Finally, based on the previously derived elastic and inelastic spectra, equations suitable for design and/or assessment purposes, are proposed for the corresponding displacement modification factors

Realism and Objectivism in Quantum Mechanics

The present study attempts to provide a consistent and coherent account of what the world could be like, given the conceptual framework and results of contemporary quantum theory. It is suggested that standard quantum mechanics can, and indeed should, be understood as a realist theory within its domain of application. It is pointed out, however, that a viable realist interpretation of quantum theory requires the abandonment or radical revision of the classical conception of physical reality and its traditional philosophical presuppositions. It is argued, in this direction, that the conceptualization of the nature of reality, as arising out of our most basic physical theory, calls for a kind of contextual realism. Within the domain of quantum mechanics, knowledge of 'reality in itself', 'the real such as it truly is' independent of the way it is contextualized, is impossible in principle. In this connection, the meaning of objectivity in quantum mechanics is analyzed, whilst the important question concerning the nature of quantum objects is explored.Comment: 20 pages. arXiv admin note: substantial text overlap with arXiv:0811.3696, arXiv:quant-ph/0502099, arXiv:0904.2702, arXiv:0904.2859, arXiv:0905.013

Pathological serosa and node-based classification accurately predicts gastric cancer recurrence risk and outcome, and determines potential and limitation of a Japanese-style extensive surgery for Western patients: A prospective with quality control 10-year follow-up study

UICC classification accurately predicts overall survival but not recurrence-risk. We report here data of overall and first site-specific recurrence following curative surgery useful for the development of recurrence-oriented preventive target therapies. Patients who underwent resection for gastric cancer were stratified according to curability of surgery [curative (R0) vs non-curative resection], extent of surgery [limited (D1) vs extended (D2) node dissection] and pathological nodal/serosal status. The intent-to-treat principle, log-rank test and Cox regression analysis were used for statistical analysis of time-to-event (recurrence, death) endpoints. Curative resection only produced a chance of cure whereas survival was very poor following non-curative resection (P < 0.0001). For D2 R0 subgroup of patients, a pathological serosa and a node state-based classification into three groups, proved to be of clinical implication. Risk of recurrence after a median follow-up of 92 months was low among patients with both serosa and node-negative cancer (first group; 11%), moderate among those with either serosa or node-positive cancer (second group; 53%) and very high among those with both serosa and node-positive cancer (third group; 83%). In multivariate analysis, the relative risks of recurrence and death from gastric cancer among patients in the second and third groups, as compared to those in the first, were 7.07 (95% CI, 2.36–21.17;P  = 0.0002) and 16.19 (95% CI, 5.76–45.54;P < 0.0001) respectively. First site-specific recurrence analysis revealed: low rate of loco-regional recurrence alone (12%), serosa state determinant factor of the site-recurrence (peritoneal for serosa-positive and haematogenous for serosa-negative cancers) and dramatic increase of all types of recurrence by the presence of nodal metastases. Our findings demonstrate that a pathological serosa- and node-based classification is very simple and predicts accurately site-specific recurrence-risks. Furthermore they reveal that risk of recurrence following curative D2 surgery alone is low for serosa- and node-negative cancers, but very high in serosa- and node-positive cancers suggesting the need for new therapeutic strategies in this subgroup of patients. © 2001 Cancer Research Campaign http://www.bjcancer.co

THGEM-based detectors for sampling elements in DHCAL: laboratory and beam evaluation

We report on the results of an extensive R&D program aimed at the evaluation of Thick-Gas Electron Multipliers (THGEM) as potential active elements for Digital Hadron Calorimetry (DHCAL). Results are presented on efficiency, pad multiplicity and discharge probability of a 10x10 cm2 prototype detector with 1 cm2 readout pads. The detector is comprised of single- or double-THGEM multipliers coupled to the pad electrode either directly or via a resistive anode. Investigations employing standard discrete electronics and the KPiX readout system have been carried out both under laboratory conditions and with muons and pions at the CERN RD51 test beam. For detectors having a charge-induction gap, it has been shown that even a ~6 mm thick single-THGEM detector reached detection efficiencies above 95%, with pad-hit multiplicity of 1.1-1.2 per event; discharge probabilities were of the order of 1e-6 - 1e-5 sparks/trigger, depending on the detector structure and gain. Preliminary beam tests with a WELL hole-structure, closed by a resistive anode, yielded discharge probabilities of <2e-6 for an efficiency of ~95%. Methods are presented to reduce charge-spread and pad multiplicity with resistive anodes. The new method showed good prospects for further evaluation of very thin THGEM-based detectors as potential active elements for DHCAL, with competitive performances, simplicity and robustness. Further developments are in course.Comment: 15 pages, 11 figures, MPGD2011 conference proceedin

Microearthquake study of the broader Thessaloniki area (Northern Greece)

A temporary network of twelve portable digital seismological stations was operated around the city of Thessaloniki (Northern Greece) for a period of 19 months (from July 2001 to April 2002 and from October 2002 to August 2003), providing data that enabled the study of the interconnection between microseismicity and active tectonics in the area. During the operation period 277 microearthquakes that were recorded in more than four stations were accurately located and 64 fault plane solutions were determined. Seismic activity is associated with ENE-WSW, E-W and ESE-WNW striking normal faults and is nearly confined to the first 15 km, thus defining the seismogenic layer in the study area. The mean orientation of the axis of maximum extension (T-axis) is NS to NNE-SSW, determined from fault plane solutions, in agreement with the regional extensional stress pattern, which strikes perpendicular to the orientation of the main WNW-ESE active faults of the area

Bribing to Queue-Jump: An experiment on cultural differences in bribing attitudes among Greeks and Germans

We study the role of culture on bribing attitudes in a new dynamic bribery game, where the purpose of bribing is to receive a service earlier by bribing to queue-jump. Our queue-jumping game allows us to distinguish between two classes of bribes: (i) queue-jumping bribes, which aim to increase the briber's expected earnings by jumping the queue, and (ii) counter bribes, which aim to maintain the briber's expected earnings by upholding the current order in the queue. In a laboratory experiment, comprised of four treatments that differ in the number of Greeks and Germans in each group, we analyze both cross-cultural and inter-cultural differences in bribing attitudes. In our cross-cultural treatments, we find that Greeks tend to bribe more often than Germans, but only in the early periods of the game. As time progresses, the Germans quickly catch-up, bribing as often as the Greeks. However, the observed differences in bribe rates in the early periods of the game are driven by queue-jumping bribes rather than counter-bribes. As the ratio of counter-bribes to queue-jumping bribes is significantly lower among Greeks relative to Germans, bribing to queue-jump is more profitable in the Greek groups. In our inter-cultural treatments, we find that minorities, irrespective of nationality, bribe less, despite there are no prospects for monetary or reputational gains. We interpret this result as evidence of outgroup favoritism by minority groups

Microearthquake study of the broader Thessaloniki area (Northern Greece)

A temporary network of twelve portable digital seismological stations was operated around the city of Thessaloniki (Northern Greece) for a period of 19 months (from July 2001 to April 2002 and from October 2002 to August 2003), providing data that enabled the study of the interconnection between microseismicity and active tectonics in the area. During the operation period 277 microearthquakes that were recorded in more than four stations were accurately located and 64 fault plane solutions were determined. Seismic activity is associated with ENE-WSW, E-W and ESE-WNW striking normal faults and is nearly confined to the first 15 km, thus defining the seismogenic layer in the study area. The mean orientation of the axis of maximum extension (T-axis) is NS to NNE-SSW, determined from fault plane solutions, in agreement with the regional extensional stress pattern, which strikes perpendicular to the orientation of the main WNW-ESE active faults of the area

Observations from the March 2021 Thessaly Earthquakes: an earthquake engineering perspective for masonry structures

Two strong earthquakes hit Thessaly region on March 3rd, 2021 (Mw = 6.3) and on March 4th, 2021 (Mw = 6.1). The epicentres of the earthquakes were located at approximately 23 and 29 km respectively NW of Larissa, one of the most populous cities in Greece. Several aftershocks followed thereafter. Although no injuries were recorded, several structures suffered significant damage close to the epicentre, while some others collapsed. Approximately 300 residents of the village of Damasi were transferred to temporary settlements and tents. The event occurred during the COVID19 lockdown and created significant stress and disruption to residents. This paper focuses on the earthquake swarm itself as well as the damages observed in residential buildings, schools, and churches in the earthquake-stricken region. The earthquakes mainly impacted low-rise domestic masonry buildings, while the more modern reinforced concrete structures built following the recent seismic regulations were almost unaffected. The typology of buildings in the region, together with photographs demonstrating the extent of damage are presented herein. Despite the rather satisfactory performance of modern buildings in recent earthquakes in Greece, the preliminary investigations from the Thessaly Earthquakes showed that there is still a significant level of vulnerability in existing masonry building stock constructed using traditional methods and materials. This issue could re-emerge in future earthquakes striking other rural areas of Greece, something that needs to be addressed systematically in the future