38 research outputs found

    FIELD OBSERVATIONS OF THE 2015 (NOVEMBER 17, MW 6.4) LEFKAS (IONIAN SEA, WESTERN GREECE) EARTHQUAKE IMPACT ON NATURAL ENVIRONMENT AND BUILDING STOCK OF LEFKAS ISLAND

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    Την Τρίτη 17 Νοεμβρίου 2015 στις 09:10:07 (τοπική ώρα) εκδηλώθηκε σφοδρή σεισμική δόνηση μεγέθους Mw 6.4, βάθους περί τα 7χλμ και με επίκεντρο σε απόσταση 20 χλμ νοτιοδυτικά της πόλης της Λευκάδας. Η σεισμική δραστηριότητα στην περιοχή ήταν ουσιαστικά αναμενόμενη σε μεσοπρόθεσμη κλίμακα μετά τον σεισμό της Λευκάδας το 2003 και τους σεισμούς της Κεφαλονιάς το 2014. Στον ενδιάμεσο χώρο οι γεωτεκτονικές δυνάμεις δεν είχαν εκτονωθεί μετά τους σεισμούς του 1948 με αποτέλεσμα την εκδήλωση του πρόσφατου σεισμού, που έγινε αισθητός σε όλη τη Λευκάδα και την ευρύτερη περιοχή προκαλώντας το θάνατο 2 και τον τραυματισμό 8 κατοίκων, εκτεταμένες δευτερογενείς επιπτώσεις στο περιβάλλον και βλάβες στα κτίρια και τις υποδομές του νησιού. Οι δευτερογενείς επιπτώσεις στη δυτική Λευκάδα διακρίθηκαν σε εδαφικές ρωγμές, αστοχίες πρανών και ρευστοποίηση. Πρωτογενείς επιπτώσεις δεν παρατηρήθηκαν. Κτιριακές βλάβες σημειώθηκαν κυρίως σε οικισμούς στο βύθισμα Δράγανου-Αθάνιου στη νοτιοδυτική Λευκάδα. Από τα κτίρια, που έχουν κατασκευαστεί χωρίς αντισεισμικό σχεδιασμό, τα πετρόκτιστα κτίρια και οι ιστορικές και μνημειακές κατασκευές υπέστησαν τις σοβαρότερες βλάβες, ενώ τα παραδοσιακά κτίρια με διπλό δομικό σύστημα ανάληψης φορτίων συμπεριφέρθηκαν ικανοποιητικά. Τα κτίρια με οπλισμένο σκυρόδεμα επηρεάστηκαν όχι τόσο από το σεισμό αλλά από τις δευτερογενείς επιπτώσεις του στο περιβάλλον.On Tuesday, November 17, 2015 at 07:10:07 (UTC) a strong earthquake struck Lefkas Island (Ionian Sea, Western Greece) with magnitude Mw 6.4, depth of about 7 km and epicenter located 20 km southwest of Lefkas town. The seismic activity in the region was essentially expected after the 2003 Lefkas earthquake and the 2014 Cephalonia earthquakes. Between these earthquake affected areas, the tectonic stresses were not released after the 1948 Lefkas earthquakes. Instead, they were intensifying and accumulating until the generation of the 2015 event. It was felt in Lefkas and the surrounding region and caused the death of 2 people, the injury of 8 others, earthquake environmental effects (EEE) and damage to buildings and infrastructure. Secondary EEE were observed in western Lefkas and included ground cracks, slope movements and liquefaction. Primary effects were not detected in the field. Buildings damage were mainly observed in villages of Dragano-Athani graben in southwestern Lefkas. Among structures constructed with no seismic provisions, the stone masonry buildings and monumental structures suffered most damage, while the traditional buildings with dual structural system performed relatively well. Reinforced-concrete buildings were affected not so much by the earthquake itself but by the generation of secondary effects

    Probing the atmosphere of HD189733b with the Na I and K I lines

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    High spectral resolution transmission spectroscopy is a powerful tool to characterize exoplanet atmospheres. Especially for hot Jupiters, this technique is highly relevant, due to their high altitude absorption e.g. from resonant sodium (Na I) and potassium (K I) lines. We resolve the atmospheric K I-absorption on HD189733b with the aim to compare the resolved K I -line and previously obtained high resolution Na I-D-line observations with synthetic transmission spectra. The line profiles suggest atmospheric processes leading to a line broadening of the order of 10 km/s for the Na I-D-lines, and only a few km/s for the K I-line. The investigation hints that either the atmosphere of HD189733b lacks a significant amount of K I or the alkali lines probe different atmospheric regions with different temperature, which could explain the differences we see in the resolved absorption lines

    Temperature and wavelength drift tolerant WDM transmission and routing in on-chip silicon photonic interconnects

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    We demonstrate a temperature and wavelength shift resilient silicon transmission and routing interconnect system suitable for multi-socket interconnects, utilizing a dual-strategy CLIPP feedback circuitry that safeguards the operating point of the constituent photonic building blocks along the entire on-chip transmission-multiplexing-routing chain. The control circuit leverages a novel control power-independent and calibration-free locking strategy that exploits the 2nd derivative of ring resonator modulators (RMs) transfer function to lock them close to the point of minimum transmission penalty. The system performance was evaluated on an integrated Silicon Photonics 2-socket demonstrator, enforcing control over a chain of RM-MUX-AWGR resonant structures and stressed against thermal and wavelength shift perturbations. The thermal and wavelength stress tests ranged from 27 degrees C to 36 degrees C and 1309.90 nm to 1310.85 nm and revealed average eye diagrams Q-factor values of 5.8 and 5.9 respectively, validating the system robustness to unstable environments and fabrication variations. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreemen

    Spastic paraplegia preceding PSEN1-related familial Alzheimer's disease.

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    Introduction: We investigated the frequency, neuropathology, and phenotypic characteristics of spastic paraplegia (SP) that precedes dementia in presenilin 1 (PSEN1) related familial Alzheimer's disease (AD). Methods: We performed whole exome sequencing (WES) in 60 probands with hereditary spastic paraplegia (HSP) phenotype that was negative for variants in known HSP-related genes. Where PSEN1 mutation was identified, brain biopsy was performed. We investigated the link between HSP and AD with PSEN1 in silico pathway analysis and measured in vivo the stability of PSEN1 mutant γ-secretase. Results: We identified a PSEN1 variant (p.Thr291Pro) in an individual presenting with pure SP at 30 years of age. Three years later, SP was associated with severe, fast cognitive decline and amyloid deposition with diffuse cortical plaques on brain biopsy. Biochemical analysis of p.Thr291Pro PSEN1 revealed that although the mutation does not alter active γ-secretase reconstitution, it destabilizes γ-secretase-amyloid precursor protein (APP)/amyloid beta (Aβn) interactions during proteolysis, enhancing the production of longer Aβ peptides. We then extended our analysis to all 226 PSEN1 pathogenic variants reported and show that 7.5% were associated with pure SP onset followed by cognitive decline later in the disease. We found that PSEN1 cases manifesting initially as SP have a later age of onset, are associated with mutations located beyond codon 200, and showed larger diffuse, cored plaques, amyloid-ring arteries, and severe CAA. Discussion: We show that pure SP can precede dementia onset in PSEN1-related familial AD. We recommend PSEN1 genetic testing in patients presenting with SP with no variants in known HSP-related genes, particularly when associated with a family history of cognitive decline

    Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

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    PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

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    PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Thrombosis in vasculitis: from pathogenesis to treatment

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    Kawasaki disease: Current aspects on aetiopathogenesis and therapeutic management

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    Kawasaki disease (KD) is a vasculitis that affects mainly children of 6 months to 4 years old. It is important to be early recognised so as to limit the inflammatory cascade that may lead to aneurysmatic dilatations of coronary arteries. The causative agent of KD has not been still indentified and the aetiopathogenetic theories are based on epidemiologic, laboratory and histological data. The management of the disease is divided according to the clinical stage and patients' follow up should be continued for years after the disease onset. The exact period is determined by the risk level of the KD. © 2011 Elsevier B.V
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