1,721,186 research outputs found
Crustal movements in northeastern Italy derived from permanent GPS stations
No full textThe horizontal absolute motion vectors of northeastern Italy, obtained from the GPS data of the permanent stations of the Department of Physics of the University of Bologna, are quite similar to the NUVEL1A NNR plate motion model. However, the results indicate that these sites are moving faster than predicted by the model and with azimuths slightly more northward oriented. The directions of absolute motion in the no-net-rotation system confirm the motion of the Adriatic plate in the global circuit where both Africa, Europe and the intervening Adriatic plate are moving north-eastward, although at different velocities and with small variable azimuths which determine relative plate interactions. The motions of the Marina di Ravenna, Medicina and Bologna stations are respectively 30.9, 27.6, and 29.4 mm/yr; Trieste moves at a rate of 27.9 mm/yr. The azimuths have similar values. The data suggest shortening of about 2-to-4 mm/yr between Trieste, located at the leading edge of the Dinarides orogen and the Emilia-Romagna Marina di Ravenna, Medicina and Bologna sites positioned above the Apennines accretionary prism. This can be interpreted either as active thrusting of the Dinarides or/and active thrusting in the Apennines accretionary prism. Seismic reflection profiles and seismicity indicate that both orogens are active, but the Dinarides appear to have slower convergence rates. Active thrusting supports the notion of a lively and retreating subduction beneath the northern Apennines. The height time data of the same sites show subsidence rates of different magnitude: Medicina -2.44 0.05 mm/yr; Marina di Ravenna –10.82 0.04; Bologna –17.93 0.09; Trieste –5.71 0.10. The rates of Marina di Ravenna and Bologna are, to a large extent, of anthropogenic nature. They were induced by groundwater exploitation, which was subjected to control policies only starting from the early 80's. These values indicate faster subsidence close to the depocenter of the Apennines foredeep (Bologna), with lower values above anticlines of the accretionary prism (Medicina). Subsidence in Marina di Ravenna can be interpreted as related to both foredeep subsidence plus sediment loading and natural and anthropogenic compaction in the Po delta area
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Variations on the Author
Full text link“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
Immunocytochemical localization of progesterone receptors in endocrine cells of the human pancreas
No full textProgesterone receptors (PgR) have been immunocytochemically localized in the nuclei of several (40% to 75%) endocrine cells of the human pancreas and in a more variable number of neoplastic cells of 7 of 18 endocrine pancreatic tumors. Conversely the exocrine epithelial cells of the pancreas did not exhibit any PgR immunoreactivity in normal as well as in different pathologic conditions, including pancreatic adenocarcinomas. Estrogen receptors were not detected in any of the pancreatic samples investigated. Double immunocytochemical experiments have documented that PgR immunoreactivity in normal Langerhans islets is a consistent feature of most (75%) glucagon-producing A cells, of approximately 5% to 20% of insulin-producing B cells, and of a variable percentage of pancreatic polypeptide (PP)-producing cells, ranging from 5% to 70%. These figures were not affected by the sex, age, or underlying disease of the patients. The reported findings corroborate previous clinical and experimental evidence indicating that sex steroid hormones may have some regulatory effects on the functional activity of the endocrine pancreas
Immunohistochemical evidence of abnormal expression of the antioncogene-encoded p53 phosphoprotein in Hodgkin's disease and CD30+ anaplastic lymphomas
No full textThe gene encoding p53 phosphoprotein, originally believed to be an oncogene, recently has been proposed as a candidate antioncogene (tumor-suppressor gene). Abnormalities of the p53 gene expression have been demonstrated in different human malignancies including carcinomas and sarcomas, but little information concerning p53 immunoreactivity in human lymphomas is so far available. In this study immunohistochemical staining for p53-protein was performed on frozen- and paraffin-embedded samples from patients with Hodgkin's (HD) and non-Hodgkin's lymphomas (NHL). No p53 immunoreactivity could be demonstrated in any cell type in nonneoplastic lymphoid samples, including germinal center cells in reactive lymph nodes and cortical thymocytes. On the other hand, a significant proportion of p53+ neoplastic cells was observed in 23 of 31 cases of HD and 17 of 68 cases of NHL. All positive lymphoma cases were diagnosed as high-grade or CD30+ anaplastic NHL. The demonstration of abnormal expression of p53 protein in these diseases can contribute to addressing unresolved issues regarding the origin and pathogenesis of HD and CD30+ anaplastic lymphomas
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Full text linkWe 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
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