Historical earthquake investigations in Greece

The active tectonics of the area of Greece and its seismic activity have always been present in the country’s history. Many researchers, tempted to work on Greek historical earthquakes, have realized that this is a task not easily fulfilled. The existing catalogues of strong historical earthquakes are useful tools to perform general SHA studies. However, a variety of supporting datasets, non-uniformly distributed in space and time, need to be further investigated. In the present paper, a review of historical earthquake studies in Greece is attempted. The seismic history of the country is divided into four main periods. In each one of them, characteristic examples, studies and approaches are presented

A CROSS-CORRELATION TECHNIQUE FOR RELOCATION OF SEISMICITY IN THE WESTERN CORINTH RIFT

Local seismological networks provide data that allow the location of microearthquakes which otherwise would be dismissed due to low magnitudes and low signal-to-noise ratios of their seismic signals. The Corinth Rift Laboratory (CRL) network, installed in the western Corinth rift, has been providing digital waveform data since 2000. In this work, a semi-automatic picking technique has been applied which exploits the similarity between waveforms of events that have occurred in approximately the same area of an active fault. Similarity is measured by the crosscorrelation maxi-mum of full signals. Events with similar waveforms are grouped in multiplet clusters using the nearest-neighbour linkage algorithm. Manually located events act as masters, while automatically located events of each multiplet cluster act as slaves. By cross-correlating the P-wave or S-wave segments of a master event with the corresponding segments of each of its slave events, after appropriately aligning their offsets, the measured time-lag at the cross-correlation maximum can be subtracted from the arrival-time of the slave event. After the correction of the arrival-times, a double-difference technique is applied to the modified catalogue to further improve the locations of clusters and distinguish the active seismogenic structures in the tectonically complex Western Corinth rift

Νεολαία και Ευρωπαϊκή Ένωση: Στάσεις, Προσδιοριστικοί Παράγοντες και Διαγενεακές Δυναμικές

Η παρούσα έκθεση πραγματεύεται τις ελληνικές στάσεις απέναντι στην ευρωπαϊκή ολοκλήρωση, με ιδιαίτερη έμφαση στην νεολαία. Από τη λεπτομερή ανάλυση πρωτογενών δεδομένων εντοπίστηκαν διακριτές διαφορές μεταξύ των γενεών, ανάμεσα στα άτομα ηλικίας κάτω και άνω των 35 ετών, τόσο στην εξέλιξη όσο και στους προσδιοριστικούς παράγοντες των στάσεων απέναντι στην Ευρωπαϊκή Ένωση (ΕΕ).Πρώτον, οι νέοι Έλληνες είναι γενικά πιο θετικά διακείμενοι απέναντι στην ΕΕ και πιο αισιόδοξοι για το μέλλον της σε σύγκριση με τις ομάδες μεγαλύτερης ηλικίας. Η εθνική (ελληνική) τους ταυτότητα δεν έρχεται σε αντίθεση με την ευρωπαϊκή : και οι δύο συνυπάρχουν και είναι αμφότερα σημαντικές για το πώς οι νέοι αξιολογούν τις μελλοντικές προοπτικές τους. Αντιθέτως, ο βαθμός στον οποίο οι νέοι είναι ευχαριστημένοι συνολικά από τη ζωή τους στην Ελλάδα επηρεάζει, σε μεγάλο βαθμό, τον τρόπο που βλέπουν την ΕΕ.Δεύτερον, οι νέοι Έλληνες έχουν απόλυτη συνείδηση ​​των ελλείψεων της ευρωπαϊκής ενοποίησης, όπως αυτές εκδηλώθηκαν στον χειρισμό της οικονομικής κρίσης. Συγκεκριμένα, θεωρούν ότι η ΕΕ έχει επωφεληθεί δυσανάλογα από την ελληνική ένταξη και όχι το αντίστροφο και είναι επικριτικοί για τον χειρισμό της κρίσης τόσο από τις ελληνικές κυβερνήσεις, όσο και από την ΕΕ.Τρίτον, μολαταύτα, οι νέοι στην Ελλάδα αρνούνται να συμμετάσχουν σε παιχνίδια απόδοσης ευθυνών για το ποιός έκανε τί και πότε. Αντιθέτως, επικεντρώνονται σε συγκεκριμένες δημόσιες πολιτικές, αναμένοντας ότι η ΕΕ θα συνεχίσει να βοηθά τη χώρα τους στο χειρισμό διεθνικών προβλημάτων, όπως η κλιματική αλλαγή και η μετανάστευση, και υποστηρίζοντας  τις μεταρρυθμίσεις της ελληνικής δημόσιας διοίκησης σύμφωνα με τις βέλτιστες πρακτικές της ΕΕ.Τέταρτον, οι νέοι Έλληνες απέχουν πολύ από το εγωιστικό στερεότυπο της μεγιστοποίησης της ατομικής ωφέλειας. Η στάση τους προς την ΕΕ επηρεάζεται έντονα από αυτό που θεωρούν ότι είναι συμφέρον της χώρας και όχι από τις προσωπικές τους οικονομικές συνθήκες. Οι νέοι επίσης αποδέχονται εμφατικά την προσωπική ευθύνη για την αντιμετώπιση συλλογικών προβλημάτων.Τέλος, οι στάσεις για την ευρωπαϊκή ενοποίηση επηρεάζονται από πολύ συγκεκριμένους στόχους πολιτικής. Η υποστήριξη στην ΕΕ συμβαδίζει με θετικές στάσεις απέναντι στην ιδιωτική επιχείρηση, την επιχειρηματικότητα, τις πολιτικές υπέρ της ανάπτυξης, τη μείωση της ανισότητας και του αυταρχισμού. Εκείνοι που βλέπουν την κρίση ως ευκαιρία υποστηρίζουν την περαιτέρω ολοκλήρωση, έχοντας επίγνωση του γεγονότος ότι οι κρίσεις μας επιτρέπουν να επανεκτιμήσουμε λάθη του παρελθόντος και να χαράξουμε νέες προοπτικές για το μέλλον. Το κεντρικό συμπέρασμα της έκθεσης, οπως προκύπτει από τη διεξοδική ανάλυση πρωτογενών δεδομένων, είναι ότι οι καλές πολιτικές, και όχι μόνον η καλή πολιτική, αποτελεί τον αποτελεσματικότερο τρόπο για να εδραιωθεί η ευρωπαϊκή προοπτική της Ελλάδας.Institutions, Decisions and Collective Behaviou

Resting State fMRI in the moving fetus: A robust framework for motion, bias field and spin history correction

There is growing interest in exploring fetal functional brain development, particularly with Resting State fMRI. However, during a typical fMRI acquisition, the womb moves due to maternal respiration and the fetus may perform large-scale and unpredictable movements. Conventional fMRI processing pipelines, which assume that brain movements are infrequent or at least small, are not suitable. Previous published studies have tackled this problem by adopting conventional methods and discarding as much as 40% or more of the acquired data. In this work, we developed and tested a processing framework for fetal Resting State fMRI, capable of correcting gross motion. The method comprises bias field and spin history corrections in the scanner frame of reference, Combined with slice to volume registration and scattered data interpolation to place all data into a consistent anatomical space. The aim is to recover an ordered set of samples suitable for further analysis using standard tools such as Group Independent Component Analysis (Group ICA). We have tested the approach using simulations and in vivo data acquired at 1.5 T. After full motion correction, Group ICA performed on a population of 8 fetuses extracted 20 networks, 6 of which were identified as matching those previously observed in preterm babies

Punctate White Matter Lesions Associated With Altered Brain Development And Adverse Motor Outcome In Preterm Infants.

Preterm infants who develop neurodevelopmental impairment do not always have recognized abnormalities on cerebral ultrasound, a modality routinely used to assess prognosis. In a high proportion of infants, MRI detects punctate white matter lesions that are not seen on ultrasonography. To determine the relation of punctate lesions to brain development and early neurodevelopmental outcome we used multimodal brain MRI to study a large cohort of preterm infants. Punctate lesions without other focal cerebral or cerebellar lesions were detected at term equivalent age in 123 (24.3%) (59 male) of the 506 infants, predominantly in the centrum semiovale and corona radiata. Infants with lesions had higher gestational age, birth weight, and less chronic lung disease. Punctate lesions showed a dose dependent relation to abnormalities in white matter microstructure, assessed with tract-based spatial statistics, and reduced thalamic volume (p < 0.0001), and predicted unfavourable motor outcome at a median (range) corrected age of 20.2 (18.4-26.3) months with sensitivity (95% confidence intervals) 71 (43-88) and specificity 72 (69-77). Punctate white matter lesions without associated cerebral lesions are common in preterm infants currently not regarded as at highest risk for cerebral injury, and are associated with widespread neuroanatomical abnormalities and adverse early neurodevelopmental outcome

Comparing cost-effectiveness of surface water flood management interventions in a UK catchment

This is the final published version. Available from Wiley via the DOI in this record.Despite significant consequences caused by recent events, surface water flooding has historically been of lower priority relative to fluvial and coastal risks in UK flood management. Legislation and research proposes a variety of innovative interventions to address this; however, widespread application of these remains a challenge due to a number of institutional, economic, and technical barriers. This research applies a framework capable of fast and high-resolution assessment of intervention cost-effectiveness as an opportunity to improve available evidence and encourage uptake of interventions through analysing permutations of type, scale, and distribution in urban catchments. Fast assessment of many scenarios is achieved using a cellular automata flood model and a simplified representation of interventions. Conventional and green strategies are examined across a range of design standard and high-magnitude rainfall events in an urban catchment. Results indicate high-volume rainwater capture interventions demonstrate a significant reduction in estimated annual damage costs, and localised surface water drainage interventions exhibit high cost-effectiveness for damage reduction. Analysis of performance across a wide range of return periods enhances available evidence for option comparison decision support and provides a basis for future resilience assessment of interventions.Engineering and Physical Sciences Research Council (EPSRC

Cortical morphology at birth reflects spatiotemporal patterns of gene expression in the fetal human brain.

Funder: Royal Children's Hospital Foundation; funder-id: http://dx.doi.org/10.13039/100014607Funder: FP7 Ideas: European Research Council (); Grant(s): 319456Interruption to gestation through preterm birth can significantly impact cortical development and have long-lasting adverse effects on neurodevelopmental outcome. We compared cortical morphology captured by high-resolution, multimodal magnetic resonance imaging (MRI) in n = 292 healthy newborn infants (mean age at birth = 39.9 weeks) with regional patterns of gene expression in the fetal cortex across gestation (n = 156 samples from 16 brains, aged 12 to 37 postconceptional weeks [pcw]). We tested the hypothesis that noninvasive measures of cortical structure at birth mirror areal differences in cortical gene expression across gestation, and in a cohort of n = 64 preterm infants (mean age at birth = 32.0 weeks), we tested whether cortical alterations observed after preterm birth were associated with altered gene expression in specific developmental cell populations. Neonatal cortical structure was aligned to differential patterns of cell-specific gene expression in the fetal cortex. Principal component analysis (PCA) of 6 measures of cortical morphology and microstructure showed that cortical regions were ordered along a principal axis, with primary cortex clearly separated from heteromodal cortex. This axis was correlated with estimated tissue maturity, indexed by differential expression of genes expressed by progenitor cells and neurons, and engaged in stem cell differentiation, neuron migration, and forebrain development. Preterm birth was associated with altered regional MRI metrics and patterns of differential gene expression in glial cell populations. The spatial patterning of gene expression in the developing cortex was thus mirrored by regional variation in cortical morphology and microstructure at term, and this was disrupted by preterm birth. This work provides a framework to link molecular mechanisms to noninvasive measures of cortical development in early life and highlights novel pathways to injury in neonatal populations at increased risk of neurodevelopmental disorder

Automated processing pipeline for neonatal diffusion MRI in the developing Human Connectome Project

The developing Human Connectome Project is set to create and make available to the scientific community a 4-dimensional map of functional and structural cerebral connectivity from 20 to 44 weeks post-menstrual age, to allow exploration of the genetic and environmental influences on brain development, and the relation between connectivity and neurocognitive function. A large set of multi-modal MRI data from fetuses and newborn infants is currently being acquired, along with genetic, clinical and developmental information. In this overview, we describe the neonatal diffusion MRI (dMRI) image processing pipeline and the structural connectivity aspect of the project. Neonatal dMRI data poses specific challenges, and standard analysis techniques used for adult data are not directly applicable. We have developed a processing pipeline that deals directly with neonatal-specific issues, such as severe motion and motion-related artefacts, small brain sizes, high brain water content and reduced anisotropy. This pipeline allows automated analysis of in-vivo dMRI data, probes tissue microstructure, reconstructs a number of major white matter tracts, and includes an automated quality control framework that identifies processing issues or inconsistencies. We here describe the pipeline and present an exemplar analysis of data from 140 infants imaged at 38-44 weeks post-menstrual age

The Corinth Rift Laboratory, Greece (CRL): A Multidisciplinary Near Fault Observatory (NFO) on a Fast Rifting System

The western rift of Corinth (Greece) is one of the most active tectonic structures of the euro-mediterranean area. Its NS opening rate is 1.5 cm/yr ( strain rate of 10-6/yr) results into a high microseismicity level and a few destructive, M>6 earthquakes per century, activating a system of mostly north dipping normal faults. Since 2001, monitoring arrays of the European Corinth Rift Laboratory (CRL, www.crlab.eu) allowed to better track the mechanical processes at work, with short period and broad band seismometers, cGPS, borehole strainmeters, EM stations, …). The recent (300 kyr) tectonic history has been revealed by onland (uplifted fan deltas and terraces) and offshore geological studies (mapping, shallow seismic, coring), showing a fast evolution of the normal fault system. The microseismicity, dominated by swarms lasting from days to months, mostly clusters in a layer 1 to 3 km thick, between 6 and 9 km in depth, dipping towards north, on which most faults are rooting. The diffusion of the microseismicity suggests its triggering by pore pressure transients, with no or barely detected strain. Despite a large proportion of multiplets, true repeaters seem seldom, suggesting a minor contribution of creep in their triggering, although transient or steady creep is clearly detected on the shallow part of some majors faults. The microseismic layer may thus be an immature, downward growing detachment, and the dominant rifting mechanism might be a mode I, anelastic strain beneath the rift axis , for which a mechanical model is under development. Paleoseismological (trenching, paleoshorelines, turbidites), archeological and historical studies completed the catalogues of instrumental seismicity, motivating attempts of time dependent hazard assessment. The Near Fault Observatory of CRL is thus a multidisciplinary research infrastructure aiming at a better understanding and modeling of multiscale, coupled seismic/aseismic processes on fault systems.Grant for Researchers (CC) ID 188753

How to use the world's scarce selenium resources efficiently to increase the selenium concentration in food

The world's rare selenium resources need to be managed carefully. Selenium is extracted as a by-product of copper mining and there are no deposits that can be mined for selenium alone. Selenium has unique properties as a semi-conductor, making it of special value to industry, but it is also an essential nutrient for humans and animals and may promote plant growth and quality. Selenium deficiency is regarded as a major health problem for 0.5 to 1 billion people worldwide, while an even larger number may consume less selenium than required for optimal protection against cancer, cardiovascular diseases and severe infectious diseases including HIV disease. Efficient recycling of selenium is difficult. Selenium is added in some commercial fertilizers, but only a small proportion is taken up by plants and much of the remainder is lost for future utilization. Large biofortification programmes with selenium added to commercial fertilizers may therefore be a fortification method that is too wasteful to be applied to large areas of our planet. Direct addition of selenium compounds to food (process fortification) can be undertaken by the food industry. If selenomethionine is added directly to food, however, oxidation due to heat processing needs to be avoided. New ways to biofortify food products are needed, and it is generally observed that there is less wastage if selenium is added late in the production chain rather than early. On these bases we have proposed adding selenium-enriched, sprouted cereal grain during food processing as an efficient way to introduce this nutrient into deficient diets. Selenium is a non-renewable resource. There is now an enormous wastage of selenium associated with large-scale mining and industrial processing. We recommend that this must be changed and that much of the selenium that is extracted should be stockpiled for use as a nutrient by future generations