89 research outputs found

    PETROLOGY, GEOCHEMISTRY AND GEOTECTONIC SETTING OF THE TITAROS OPHIOLITE AND ASSOCIATED PELAGONIAN BASEMENT ROCKS IN THE AREA NW OF MT. OLYMPOS, GREECE

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    To οφιολιθικό σύμπλεγμα του όρους Τίταρος στην περιοχή ΒΔ του Ολύμπου βρίσκεται επωθημένο σε Περμο-Αιθανθρακοφόρους γρανιτικούς ορθογνεύσιους και άγνωστης ηλικίας αμφιβολίτες στο ανατολικό περιθώριο της Πελαγονικής μάζας. Αποτελείται από μανδυακό περιδοτίτη χαρτσβουργιτικής σύστασης με κατά τόπους εμφανίσεις χρωμίτη και ένα καλά ανεπτυγμένο μαγματικό θάλαμο με κυκλικές ενότητες σωρειτικών πετρωμάτων δουνίτη-λερζόλιθου-βερλίτη-πυροξενίτη που μεταβαίνουν σε συμπαγείς γάββρους με φωλιές πλαγιογρανιτών και διαβασικές φλέβες στα ανώτερα τμήματα τους. Χημικές αναλύσεις ορυκτών και ολικού πετρώματος φανερώνουν συνθήκες γένεσης του οφιόλιθου σε ένα καθαρά ωκεάνειο περιβάλλον επάνω από μία ζώνη κατάδυσης πλάκας και την περιστασιακή συμμετοχή τηγμάτων προερχόμενων από καταδυθέντα ιζήματα. Οι αμφιβολίτες του κρυσταλλικού υπόβαθρου δείχνουν σαφή χημική συγγένεια προς θολεϊίτες εσωτερικού πλάκας με μια ελαφρά επίδραση από ρευστά καταδυόμενης πλάκας. Εφελκυστικές γραμμώσεις ορυκτών και κινηματικοί δείκτες στους ορθογνεύσιους και αμφιβολίτες υποδηλώνουν φορά μετακίνησης του οφιόλιθου προς τα ΑΝΑ. Προτείνεται ότι οι βασαλτικοί πρωτόλιθοι των αμφιβολιτών τοποθετήθηκαν κατά τη διαμπερή ρήξη του Α. περιθωρίου της Πελαγονικής στο Περμο-Τριαδικό η οποία και κατέληξε στη μετέπειτα δημιουργία του ωκεανού του Βαρδάρη. Ο οφιόλιθος του Τίταρου σχηματίσθηκε όταν ο ωκεανός του Βαρδάρη άρχισε να κλείνει μέσω μιας διαδικασίας ενδο-ωκεάνειας κατάδυσης πλάκας με φορά προς τα ΒΑ και επακόλουθη τοποθέτηση του προς τα ΝΑ επάνω στο Α. περιθώριο της Πελαγονικής, πιθανόν κατά το Κατώτερο Κρητιδικό.The Titaros ophiolite in Greece is a coherent thrust sheet of oceanic rocL· that lies atop Permo-Carboniferous granitic orthogneisses and amphibolites of unknown age of the eastern Pelagonian margin in the area NW of Mt. Olympos. It comprises a harzburgite tectonite mantle sequence with chromite mineralisation and a welldeveloped magma chamber with cyclic units ofdunite-lherzolite-wehrlite-pyroxenite that pass upwards into massive gabbros cut by diabase dykes and locally containing plagiogranite ponds. Ophiolite mineral and whole-rock chemistry are strongly in favour of a supra-subduction zone origin in a purely oceanic setting with the occasional brawny signature of melts from subducted sediments. By contrast, the basement amphibolites display a clear within-plate tholeiitic affinity with a slight imprint of subduction-zone fluids. Mineral stretching lineations and kinematics indicators of the orthogneisses and amphibolites suggest a consistent transport direction to the WSW. It is proposed that the basaltic protoliths of the amphibolites were emplaced during Permo-Triassic rifting of the eastern Pelagonian margin that led to the subsequent formation of the Vardar Ocean. The Titaros ophiolite was formed during closure of the Vardar Ocean via northeast-directed intra-oceanic subduction and subsequent obduction towards the southwest onto the eastern Pelagonian margin, probably in the Lower Cretaceous

    Amyand's hernia-a vermiform appendix presenting in an inguinal hernia: a case series

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    <p>Abstract</p> <p>Introduction</p> <p>A vermiform appendix in an inguinal hernia, inflamed or not, is known as Amyand's hernia. Here we present a case series of four men with Amyand's hernia.</p> <p>Case presentations</p> <p>We retrospectively studied 963 Caucasian patients with inguinal hernia who were admitted to our surgical department over a 12-year period. Four patients presented with Amyand's hernia (0.4%). A 32-year-old Caucasian man had an inflamed vermiform appendix in his hernial sac (acute appendicitis), presenting as an incarcerated right groin hernia, and underwent simultaneous appendectomy and Bassini suture hernia repair. Two patients, Caucasian men aged 36 and 43 years old, had normal appendices in their sacs, which clinically appeared as non-incarcerated right groin hernias. Both underwent a plug-mesh hernia repair without appendectomy. The fourth patient, a 25-year-old Caucasian man with a large but not inflamed appendix in his sac, had a plug-mesh hernia repair with appendectomy.</p> <p>Conclusion</p> <p>A hernia surgeon may encounter unexpected intraoperative findings, such as Amyand's hernia. It is important to be prepared and apply the appropriate treatment.</p

    Challenges to evidence synthesis and identification of data gaps in human biomonitoring

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    The increasing number of human biomonitoring (HBM) studies undertaken in recent decades has brought to light the need to harmonise procedures along all phases of the study, including sampling, data collection and analytical methods to allow data comparability. The first steps towards harmonisation are the identification and collation of HBM methodological information of existing studies and data gaps. Systematic literature reviews and meta-analyses have been traditionally put at the top of the hierarchy of evidence, being increasingly applied to map available evidence on health risks linked to exposure to chemicals. However, these methods mainly capture peer-reviewed articles, failing to comprehensively identify other important, unpublished sources of information that are pivotal to gather a complete map of the produced evidence in the area of HBM. Within the framework of the European Human Biomonitoring Initiative (HBM4EU) initiative—a project that joins 30 countries, 29 from Europe plus Israel, the European Environment Agency and the European Commission—a comprehensive work of data triangulation has been made to identify existing HBM studies and data gaps across countries within the consortium. The use of documentary analysis together with an up-to-date platform to fulfil this need and its implications for research and practice are discussed

    Diagnostic techniques for inflammatory eye disease: past, present and future: a review

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    Investigations used to aid diagnosis and prognosticate outcomes in ocular inflammatory disorders are based on techniques that have evolved over the last two centuries have dramatically evolved with the advances in molecular biological and imaging technology. Our improved understanding of basic biological processes of infective drives of innate immunity bridging the engagement of adaptive immunity have formed techniques to tailor and develop assays, and deliver targeted treatment options. Diagnostic techniques are paramount to distinguish infective from non-infective intraocular inflammatory disease, particularly in atypical cases. The advances have enabled our ability to multiplex assay small amount of specimen quantities of intraocular samples including aqueous, vitreous or small tissue samples. Nevertheless to achieve diagnosis, techniques often require a range of assays from traditional hypersensitivity reactions and microbe specific immunoglobulin analysis to modern molecular techniques and cytokine analysis. Such approaches capitalise on the advantages of each technique, thereby improving the sensitivity and specificity of diagnoses. This review article highlights the development of laboratory diagnostic techniques for intraocular inflammatory disorders now readily available to assist in accurate identification of infective agents and appropriation of appropriate therapies as well as formulating patient stratification alongside clinical diagnoses into disease groups for clinical trials

    Staurolite-forming reactions in the eastern Dalradian rocks of Scotland

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    Data on mineral and rock compositions along with textural relations are used to deduce the staurolite-forming reactions in eastern Dalradian rocks in Scotland. Initially staurolite is formed as a product of the breakdown of the assemblage chloritoid +quartz in iron-rich metapelites. With increase in grade the iron-rich rocks are succeeded by more magnesium-rich ones and staurolite is formed as a product of the breakdown of the assemblage chloritoid +chlorite+muscovite. © 1979 Springer-Verlag

    Blueschist-to-greenschist transition and the P-T path of prasinites from the Lavrion area, Greece

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    The Lavrion area is part of the Attic-Cycladic massif. Blue amphibole analyses revealed that they are glaucophane or ferroglaucophane. Ca-amphiboles are characterized as actinolite or actinolitic hornblende. The Ps component of epidotes from the glaucophane-bearing rocks varies from 25.42-30.89%, whereas the Ps component of epidotes from the greenschist assemblages ranges from 23.81-26.88%. Chlorites show narrow compositional variations of ferromagnesian ratios (Xmg=0.48-0.53). Albites are almost pure Ab100. The K-feldspar present has a low Ab content. The evolution of the prasinites studied is characterized by the progressive transformation of eclogite facies (?) rocks through epidote blueschists into greenschists. A P-T path for the prasinites is presented indicating epidote blueschist facies at P-T conditions of around 7.0-7.5 kbar and 300-340°C. Pressures of 4.0-4.5 kbar and temperatures around 340-360°C are estimated for the subsequent overprint in the greenschist facies. The path EBS to GS conditions followed under nearly isothermal uplift

    Blueschist-to-greenschist transition and the P-T path of prasinites from the Lavrion area, Greece

    No full text
    The Lavrion area is part of the Attic-Cycladic massif. Blue amphibole analyses revealed that they are glaucophane or ferroglaucophane. Ca-amphiboles are characterized as actinolite or actinolitic hornblende. The Ps component of epidotes from the glaucophane-bearing rocks varies from 25.42-30.89%, whereas the Ps component of epidotes from the greenschist assemblages ranges from 23.81-26.88%. Chlorites show narrow compositional variations of ferromagnesian ratios (Xmg=0.48-0.53). Albites are almost pure Ab100. The K-feldspar present has a low Ab content. The evolution of the prasinites studied is characterized by the progressive transformation of eclogite facies (?) rocks through epidote blueschists into greenschists. A P-T path for the prasinites is presented indicating epidote blueschist facies at P-T conditions of around 7.0-7.5 kbar and 300-340°C. Pressures of 4.0-4.5 kbar and temperatures around 340-360°C are estimated for the subsequent overprint in the greenschist facies. The path EBS to GS conditions followed under nearly isothermal uplift
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