Crustal strain in central Greece from repeated GPS measurements in the interval 1989-1997

A 66-station GPS network spanning central Greece, first observed in 1989, has been occupied fully on three occasions: June 1989, October 1991 and May 1993. Subsets of this network bounding the Gulf of Korinthos have also been occupied in June 1995, October 1995, May 1996 and September/October 1997. The first three occupations were processed using a fiducial GPS methodology, whereas later surveys were processed using CODE precise orbits. Combination of data from different surveys to yield smooth site velocities requires global network translations at each epoch to compensate for errors in the realization of the reference frame. This method provides a posteriori estimates of the relative coordinate errors and reference frame noise. Only one earthquake, the 1995 June 15 Egion event, has caused significant local coseismic displacement, and its effects on the interseismic velocity field are removed using an elastic dislocation model. We constrain the orientation of the 100 yr triangulation—GPS velocity estimates of Davies et al. (1997) using 14 sites common to the two networks. The goodness of fit of this transformation indicates that the short-term and 100 yr geodetic estimates of deformation are highly compatible. We infer that short-term geodetic studies are capable of determining longer-term deformation rates provided that transient, local effects can be modelled. From the combined velocity field, we estimate principal strains and rigid-body rotation rates at points on a regular grid using data from neighbouring sites. Strain rates are high within the Gulf of Korinthos and much lower elsewhere. The extension rate across the Gulf of Korinthos increases from east to west. Comparison of the extension rate with historical and recent rates of seismic release of strain reveals significant medium-term seismic hazard in the western Gulf of Korinthos, and may also indicate long-term aseismic strai

Geodetic strain of Greece in the interval 1892-1992

A first-order triangulation of Greece was carried out in the 1890s. Reoccupation, using Global Positioning System receivers, of 46 of the 93 original markers yielded estimates of the deformation of the region over the intervening interval. Broad regions have similar geodetic strain over the 100-year time span. Strain north of the Gulf of Korinthos is predominantly north-south extension, though with a significant east-west component. The central Peloponnisos is relatively stable, whereas the gulfs of the southern Peloponnisos are all characterized by uniaxial east-west extension. The seismic expression of strain for the entire region, calculated from the seismic moment tensors of earthquakes of MS ≥ 5.8 during the past 100 years, accounts for only 20-50% of the geodetically determined strain. At a scale of 50-100 km, the fraction of the strain that is expressed seismically varies much more than this range. In particular, whereas seismic strain in the eastern Gulf of Korinthos over the past 100 years is commensurate with the geodetic strain, there is rapid extension across the western Gulf of Korinthos (∼0.3 μstrain yr-1), with negligible seismic strain for the 100 year period prior to 1992. The Egion earthquake of June 1995 in the western Gulf of Korinthos released only a small proportion (≤20%) of the elastic strain that had accumulated in that region. The observed distribution of displacements can be explained by the relative rotation of two plates with a broad accommodation zone between them, but it is equally consistent with the deformation that would be expected of a sheet of fluid moving toward a low-pressure boundary at the Hellenic Trench. A simple calculation implies that if the region does behave as a fluid, then its effective viscosity is ∼1022-1023 Pa s. Such viscosities are consistent with the deformation of a lithosphere obeying a rheological law similar to that obtained for olivine in the laboratory

Geodetic strain of Greece in the interval 1892-1992

A first-order triangulation of Greece was carried out in the 1890s. Reoccupation, using Global Positioning System receivers, of 46 of the 93 original markers yielded estimates of the deformation of the region over the intervening interval. Broad regions have similar geodetic strain over the 100-year time span. Strain north of the Gulf of Korinthos is predominantly north-south extension, though with a significant east-west component. The central Peloponnisos is relatively stable, whereas the gulfs of the southern Peloponnisos are all characterized by uniaxial east-west extension. The seismic expression of strain for the entire region, calculated from the seismic moment tensors of earthquakes of MS ≥ 5.8 during the past 100 years, accounts for only 20-50% of the geodetically determined strain. At a scale of 50-100 km, the fraction of the strain that is expressed seismically varies much more than this range. In particular, whereas seismic strain in the eastern Gulf of Korinthos over the past 100 years is commensurate with the geodetic strain, there is rapid extension across the western Gulf of Korinthos (∼0.3 μstrain yr-1), with negligible seismic strain for the 100 year period prior to 1992. The Egion earthquake of June 1995 in the western Gulf of Korinthos released only a small proportion (≤20%) of the elastic strain that had accumulated in that region. The observed distribution of displacements can be explained by the relative rotation of two plates with a broad accommodation zone between them, but it is equally consistent with the deformation that would be expected of a sheet of fluid moving toward a low-pressure boundary at the Hellenic Trench. A simple calculation implies that if the region does behave as a fluid, then its effective viscosity is ∼1022-1023 Pa s. Such viscosities are consistent with the deformation of a lithosphere obeying a rheological law similar to that obtained for olivine in the laboratory

An Integrated Platform for Skin Cancer Heterogenous and Multilayered Data Management

Electronic health record (EHR) systems improve health care services by allowing the combination of health data with clinical decision support features and clinical image analyses. This study presents a modular and distributed platform that is able to integrate and accommodate heterogeneous, multidimensional (omics, histological images and clinical) data for the multi-angled portrayal and management of skin cancer patients. The proposed design offers a layered analytical framework as an expansion of current EHR systems, which can integrate high-volume molecular -omics data, imaging data, as well as relevant clinical observations. We present a case study in the field of dermatology, where we attempt to combine the multilayered information for the early detection and characterization of melanoma. The specific architecture aspires to lower the barrier for the introduction of personalized therapeutic approaches, towards precision medicine. The paper describes the technical issues of implementation, along with an initial evaluation of the system and discussion. © 2021, Springer Science+Business Media, LLC, part of Springer Nature