1,721,037 research outputs found

    Active Tectonics along the South East Offshore Margin of Mt. Etna: New Insights from High-Resolution Seismic Profiles

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    The offshore margin of Mt. Etna has been shaped by Middle Pleistocene to Holocene shortening and extension and, more recently, by gravity-related sliding of the volcanic edifice. These processes have acted contemporaneously although the gravitational component largely prevails over the tectonic one. In order to investigate this issue, we focused on the main role of active tectonics along the south-eastern offshore of Mt. Etna by means of marine high-resolution seismic data. Seismic profiles revealed post-220 ka sedimentary deposits unconformably overlaying the Lower-Middle Pleistocene Etnean clayey substratum and volcanics of the Basal Tholeiitic phase and the Timpe phase. Offshore Aci Trezza-Catania, the architecture of the sedimentary deposits reflects syn-tectonic deposition occurred into “piggy-back” basin setting. Shortening rate was estimated at ~0.5 mm/a since ~220 ka. Asymmetric folding also involves post Last Glacial Maximum deposits, evidencing that compressional deformation is still active. In the continental slope, a belt of normal faults offset the Lower-Middle Pleistocene Etnean clayey substratum and younger deposits, also producing seafloor ruptures. Thrust and fold structures can be related to the recent migration of the Sicilian chain front, while extensional faults are interpreted as part of a major tectonic boundary located in the Ionian offshore of Sicily

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Large Urethro-Vesico-Vaginal Fistula due to a Vaginal Foreign Body in a 22-Year-Old Woman: Case Report and Literature Review

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    In the non-industrialized countries of Africa and Asia obstetric fistulas are more frequently caused by prolonged labour, whereas in countries with developed healthcare systems they are generally the result of complications of gynaecological surgery or, rarely, benign pathologies like inflammation or foreign bodies. A 22-year-old woman was brought to the gynaecology clinic because of foul-smelling vaginal discharge. On pelvic examination a ring-like foreign body was impacted between the anterior and posterior vaginal wall. MRI scan confirmed the presence of a cylindrical foreign body in the vagina and the patient revealed that she had 'involuntarily' inserted a plastic bubble bath cap into the vagina. At surgery removal of the cap was difficult and at the end of the manoeuver evidence of a huge urethro-vesico-vaginal fistula occurred. The patient was discharged with bilateral ureteral stents and suprapubic catheter. After 3 months we performed an end-to-end anastomotic urethroplasty to repair the urethral avulsion and restored the bladder/trigonal and vaginal/cervical defects with 3 layers of sutures; 3 months later the patient had no complaints. Complex genital fistulas represent an extremely debilitating morbidity. In our case, a vaginal approach was successful, but the choice between an abdominal or vaginal approach depends on the surgeon's experience and training

    The bladder-flap ureteral augmentation: An original solution in case of complex distal stricture

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    An original surgical solution for complex stenosis of the distal ureter is presented. A young, single-kidney male patient developed a stricture of the pelvic ureter after ureteroscopy and laser lithotripsy. Surgical repair was planned after the failure of conservative management. The ureter was sectioned prevesically and spatulated; a bladder flap with the same dimensions of the ureteral plate was taken from the anterior wall, and used to augment the ureter; finally an omental flap was wrapped around the reconstructed tract. Further radiological and ureteroscopic controls showed a largely patent reconstructed ureter, and follow up proved a regularly maintained kidney function

    First comparison of subsidence/uplift rates between Copernicus European Ground Motion Service data and long-term MIS 5.5 geological record in Mediterranean regions

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    The European Ground Motion Service (EGMS), a component of the Copernicus Land Monitoring Service, offers a valuable tool for investigating vertical ground motion in coastal regions that are subject to different natural and anthropogenic processes. To conduct effective coastal assessments, it is essential to consider the multiscale interactions of these processes. This review presents a methodology for comparing EGMS Ortho (Level 3) data, based on Sentinel-1, and calibrated with measurements from the Global Navigation Satellite System (GNSS) and long-term rates based on the markers of the Marine Isotope Stage (MIS 5.5; Late Pleistocene). This study examines the Italian and Greek coasts, encompassing a range of geodynamic settings. In stable crustal segments, such as Sardinia, the EGMS Ortho (Level 3) data roughly align with both GNSS and post-MIS 5.5 rates. However, long-term based observed variations are considerably below the current 1 mm/yr EGMS precision. Conversely, in foreland basins, EGMS maps show higher values than GNSS data, which reflect regional interactions between ongoing tectonics and compaction. Local discrepancies between EGMS and GNSS in industrialized areas are attributable to industrial activities, as evidenced by the EGMS subsidence rates (8 mm/yr) observed in Ravenna, which exceed regional long-term estimates (0.8 mm/yr). In seismically active regions, such as Calabria and Sicily (e.g. the Messina Strait), the data reveals complex short- and long-term interactions linked to the seismic cycle. Conversely, in volcanic areas, like Campi Flegrei, Mt. Etna, Santorini and Nisyros, the EGMS data proves most valuable for highlighting complex volcano-tectonic movements. The findings of this study can be extended to other areas worldwide

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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