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Knowledge and visualization of the present-day relationship between earthquakes, active tectonics and crustal deformation is a key to understanding geodynamic processes, and is also essential for risk mitigation and the management of geo-reservoirs for energy and waste. The study of the complexity of the Greek tectonics has been the subject of intense efforts of our working group, employing multidisciplinary methodologies that include detailed geological mapping, geophysical and seismological data processing using innovative methods and geodetic data processing, involved in surveying at various scales. The data and results from these studies are merged with existing or updated datasets to compose the new Seismotectonic Atlas of Greece. The main objective of the Atlas is to harmonize and integrate the most recent seismological, geological, tectonic, geophysical and geodetic data in an interactive, online GIS environment. To demonstrate the wealth of information available in the end product, herein, we present thematic layers of important seismotectonic and geophysical content, which facilitates the comprehensive visualization and first order insight into seismic and other risks of the Greek territories. The future prospect of the Atlas is the incorporation of tools and algorithms for joint analysis and appraisal of these datasets, so as to enable rapid seismotectonic analysis and scenario-based seismic risk assessment.

Posiva Oy carries out research and development on spent nuclear fuel disposal in Finland. The repository will be constructed deep in the crystalline bedrock of Olkiluoto island in Eurajoki. Posiva Oy and ANDRA (France) have cooperated actively in examining methods for revealing properties of granitic bedrock. One of the considered methods was an electromagnetic cross-borehole survey, and RIM measurements were conducted in 2009. Olkiluoto migmatitic bedrock has undergone polyphasic ductile-brittle deformation and resistivity in the bedrock varies strongly in range of tens to tens of thousands of Ωm. Field work was successfully performed in one borehole pair. The results are presented in this paper. The tomographic reconstruction of the borehole section is based on the far-field approximation of the electric field. The results prove that the method can be used between boreholes to delineate and follow sulphide-bearing horizons. The detected low and high resistivity zones and their apparent shapes and orientations are in fair agreement with geological and other geophysical results. The obtained information can be used, for example, in assessing the integrity of the rock mass, as the increased electrical conductivity is often associated with rock mass deformation (clay and water bearing fractures, sulphide and graphite bearing zones).

Prior to the 7/9/1999 M^sub S^ = 5.9 Athens earthquake, regional seismicity has exhibited a power-law increase, of the form ΣΩ = K+A(t^sub c^ - t)^sup n^, where Ω is estimated using an expression log Ω = cM + d and t^sub c^ is the time of the culminating event. Such changes appeared after the 17/8/1999 M7.4 Izmit event. We quantified the performance of the power law vs. the null hypothesis of constant seismic release rates, by defining the curvature C as the ratio of the power law fit RMS/linear fit RMS, so that the smaller C is, the better the power law behaviour. By mapping C, we have established a critical radius of 110 km and observed that the region of correlated accelerating seismic release extended from the N. Aegean, through Euboea and Attica to the SW Peloponnese. A few days prior to the Athens event, min(C) was centred at the epicentral area and numerical simulation yielded t^sub c^ = 1999.676 and predicted M^sub S^ = 5.77. Seismicity rates returned to normal (quasi-constant) after the Athens event. We interpret this effect as critical point behaviour, following remote excitation of a broad area by stress redistribution due to the Izmit event which, at Athens, has triggered `premature' failure of a fault nearing its load bearing capacity. If this is correct, we have documented a case of remote earthquake triggering by another earthquake, as well as insight into the mechanisms producing it. As a corollary, we note that a large event may beget another large event in its broader region of interaction, which may be preceded by characteristic precursory seismicity changes.[PUBLICATION ABSTRACT]

We inquire the statistical nature and dynamics of shallow and deep seismogenesis along major plate margins of the NW Circum-Pacific Belt, by examining whether earthquakes are generated by Poisson processes and are independent (uncorrelated), or by Complex processes and are dependent (correlated). Analysis is based of Non Extensive Statistical Physics and the complete and homogeneous catalogue of the Japan Meteorological Agency for the period 2002-2016.5. Emphasis is given to background seismicity recovered by removing aftershocks with stochastic declustering. Long-term correlation and long-range interaction is mostly weak to moderate in shallow background seismicity. Conversely, deep seismicity is mostly uncorrelated (quasi-Poissonian), particularly in Wadati-Benioff zones. As function of time, shallow background seismicity exhibits persistent weak to moderate correlation; sub-crustal background seismicity is generally quasi-Poissonian but may dynamically transition to moderate-significant in association with temporal clusters of large earthquakes. A universal such effect was observed ahead of the 2011.19 Tohoku mega-earthquake. These results contrast observations along the Pacific-North American transformational plate boundaries of California and Alaska which are generally correlated, suggesting that the geodynamic setting is essential in the development of self-organization and Complexity. Moreover, observations appear consistent with simulations of small-world fault networks in which free boundary conditions at the surface allow for Complexity to develop, while fixed boundary conditions at depth do not.

It is shown that the Magnetotelluric (MT) impedance tensor admits an anti-symmetric generalized eigenvalue - eigenstate decomposition consistent with the anti-symmetry of electric and magnetic fields referred to the same coordinate frame: this is achieved by anti-diagonalization through rotation by 2x2 complex operators of the SU(2) rotation group. The eigenstates comprise simple proportional relationships between linearly polarized eigenvalues of the input magnetic and output electric field along the locally resistive and conductive propagation path into the Earth, respectively mediated by the maximum and minimum characteristic values of the tensor (eigen-impedances). It is shown from first principles that the eigen-impedances are expected to be positive real (passive) functions, analytic in the entire lower-half complex frequency plane and with singularities confined on the positive imaginary frequency axis. Insofar as the impedance tensor is generated by isometric transformation of the eigen-impedances, it is also passive. The expected passivity is an effective means of appraising measured tensors for compliance with the basic tenets of the MT method: it can be violated only in the presence of sources in the Earth. In addition to extrinsic effects (e.g. noise), it is demonstrated with examples, that such sources may be secondary large or small scale inductive phenomena generated by realistic conductivity configurations. However, they may not be time-independent effects taking place in a passive induction context, such as steady-state current channelling, galvanic distortion and electric field reversals. In general, to assert whether violation of passivity has occurred, it is necessary to decompose the impedance tensor, refer it to its intrinsic coordinate frame and evaluate the compliance of the eigen-impedances with their expected analytic properties

BackgroundVariation exists in practice pertaining to bowel preparation before minimally invasive colorectal surgery. A survey of EAES members prioritized this topic to be addressed by a clinical practice guideline.ObjectiveThe aim of the study was to develop evidence-informed clinical practice recommendations on the use of bowel preparation before minimally invasive colorectal surgery, through evidence synthesis and a structured evidence-to-decision framework by an interdisciplinary panel of stakeholders.MethodsThis is a collaborative project of EAES, SAGES, and ESCP. We updated a previous systematic review and performed a network meta-analysis of interventions. We appraised the certainty of the evidence for each comparison, using the GRADE and CINeMA methods. A panel of general and colorectal surgeons, infectious diseases specialists, an anesthetist, and a patient representative discussed the evidence in the context of benefits and harms, the certainty of the evidence, acceptability, feasibility, equity, cost, and use of resources, moderated by a GIN-certified master guideline developer and chair. We developed the recommendations in a consensus meeting, followed by a modified Delphi survey.ResultsThe panel suggests either oral antibiotics alone prior to minimally invasive right colon resection or mechanical bowel preparation (MBP) plus oral antibiotics; MBP plus oral antibiotics prior to minimally invasive left colon and sigmoid resection, and prior to minimally invasive right colon resection when there is an intention to perform intracorporeal anastomosis; and MBP plus oral antibiotics plus enema prior to minimally invasive rectal surgery (conditional recommendations); and recommends MBP plus oral antibiotics prior to minimally invasive colorectal surgery, when there is an intention to localize the lesion intraoperatively (strong recommendation). The full guideline with user-friendly decision aids is available in https://app.magicapp.org/#/guideline/LwvKej.ConclusionThis guideline provides recommendations on bowel preparation prior to minimally invasive colorectal surgery for different procedures, using highest methodological standards, through a structured framework informed by key stakeholders.Guideline registration number PREPARE-2023CN045.

Text simplification is crucial in bridging the comprehension gap in today’s information-rich environment. Despite advancements in English text simplification, languages with intricate grammatical structures, such as Greek, often remain under-explored. The complexity of Greek grammar, characterized by its flexible syntactic ordering, presents unique challenges that hinder comprehension for native speakers, learners, tourists, and international students. This paper introduces a comprehensive dataset for Greek text simplification, containing over 7500 sentences across diverse topics such as history, science, and culture, tailored to address these challenges. We outline the methodology for compiling this dataset, including a collection of texts from Greek Wikipedia, their annotation with simplified versions, and the establishment of robust evaluation metrics. Additionally, the paper details the implementation of quality control measures and the application of machine learning techniques to analyze text complexity. Our experimental results demonstrate the dataset’s initial effectiveness and potential in reducing linguistic barriers and enhancing communication, with initial machine learning models showing promising directions for future improvements in classifying text complexity. The development of this dataset marks a significant step toward improving accessibility and comprehension for a broad audience of Greek speakers and learners, fostering a more inclusive society.

According to the 2020 Annual Report for Atmosphere [3], this rate has varied between 42 and 55 percent over the last five years, which is consistent with the peer review study cited above. The 10th Anniversary Special Issue featured 18 peer-reviewed papers that could be categorized broadly into four topical areas, (a) societal impacts and modelling, (b) sub-seasonal and seasonal climate variability, (c) synoptic meteorology and case studies, and (d) instrumentation and operational techniques. The system is automated and ingests forecast data, but human forecasters can adjust the warnings. Since 2005, an analysis of the heat warnings in four cities has shown no trend, but does show variability consistent with severe heat waves. The surface temperature anomalies (STA) typically had an associated quadrupole structure that correlated to each NAO dipole tilt, which then had an influence on the temperature advection patterns as well.