1,721,216 research outputs found
A. CrespI, F. Stella, G. Zuccala, Commentario breve al Codice penale
No full textA. CrespI, F. Stella, G. Zuccala, Commentario breve al Codice penale. In: Revue internationale de droit comparé. Vol. 40 N°3, Juillet-septembre 1988. pp. 663-664
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
Pacemaker biologico : cellule staminali embrionali murine vs. cellule staminali cardiache adulte
Full text linkRecent progress in stem cell research makes it possible to use them in cardiac therapy. Our aim was to characterize the pacemaker current (If) and HCN channels distribution in murine embryonic stem cells and cardiac adult mesoangioblasts following differentiation towards a pacemaker-like phenotype. Mouse embryonic stem cells (mESCs) are pluripotent stem cells and they were differentiated through formation of embryoid bodies (EBs). A fraction of these cells exhibited action potentials characterized by a slow diastolic depolarization typical of pacemaker myocytes and expressed the If current. Immunofluorescence analysis revealed that both the HCN1 and HCN4 isoforms of the pacemaker channel are expressed. Rhythmic cells responded to β-adrenergic and muscarinic agonists: isoproterenol accelerated and acetylcholine slowed spontaneous rate. Accordingly, β1- and β2-adrenergic, and M2-muscarinic receptors were detected by immunofluorescence. Cardiac mesoangioblasts are vessel-associated clonogenic, self-renewing progenitor cells identified in the post-natal murine heart, which can be induced to differentiate into cardiac myocytes. A subpopulation of cardiac mesoangioblasts induced to differentiate in vitro into cardiomyocytes acquires a phenotype with specific pacemaker cells properties, such as the presence of If current and the expression of the HCN4 isoform of pacemaker channels. As in native cardiac pacemaker cells, f-channel modulation by autonomic transmitters, in these cells, contributes to control of spontaneous rate. These results show that both of these cell types express proteins which underlie generation and modulation of heart rhythm, and can represent a potential substrate for a biological pacemaker
THE NOVEL DESMOSOMAL PROTEIN POF1B IS ESSENTIAL FOR CELL-CELL ADHESION STRENGTH
Full text linkPOF1B is a candidate gene for premature ovarian failure (POF); it is mainly expressed in polarized epithelial tissues, but its function in these tissues and the relationship with the disorder are unknown. In polarized epithelial MDCK cells the human stably expressed POF1B showed a tight junction localization that was lost by the POF1B R329Q variant associated with POF. Although the apico-basal polarity markers and ultrastructure of the tight junctions were maintained in cells expressing the mutant, tight junction assembly, as well as the organization of the monolayer appeared altered. Moreover, cells expressing the POF1B R329Q variant showed defects in ciliogenesis and cystogenesis as a result of misorientation of primary cilia and mitotic division. All of these defects were explained by interference of the mutant with the content and organization of F-actin at the junctions. Subsequently, by means of morphological and biochemical criteria we documented that POF1B is actually a desmosome- associated protein. Both in Caco-2 human intestinal cells and in stratified HaCaT keratinocyte cell lines, indeed, endogenous POF1B colocalized with desmoplakin and plakophilin 2 at the desmosomal plaque and in cytoplasmic particles aligned along intermediate filaments. POF1B co-fractionated with desmosomes and intermediate filament components and showed properties characteristic of desmosomes (i.e. detergent insolubility and calcium independence). Furthermore, POF1B was required for desmosome assembly and function, as the stable downregulation of the protein in HaCaT cells caused a decrease in desmosome number and size, and these desmosomes had very weak electron dense plaques. Among the cell-cell adhesion structures, desmosomes are the most essential for mechanical coupling. The reduced capability of POF1B-silenced keratinocytes to respond to mechanical stress revealed the protein's crucial role in these junctions. Moreover, altered desmosomes in POF1B- downregulated keratinocytes were associated with altered cell proliferation and differentiation. The localization of POF1B in simple and stratified epithelia, as well as its relocation to desmosomes in human skin tumors, further indicated the protein's role in desmosome function, and suggested its involvement in human diseases associated with impairment of these junctions
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
1961-1990 high-resolution monthly precipitation climatologies for Italy
No full textHigh-resolution monthly precipitation climatologies for Italy are presented. They are based on 1961-1990 precipitation normals obtained from a quality-controlled dataset of about 6200 stations covering the Italian surface and part of the Northern neighbouring regions. The study area corresponds to the Italian administrative boundaries and includes the trans-national portions of Po basin which is the major water resource for Northern Italy. High-resolution climatologies are calculated by means of a local weighted linear regression (LWLR) of precipitation versus elevation: for each cell of a smoothed 30-arc second resolution Digital Elevation Model (DEM) the regression is performed considering the 15 stations with the highest weight. The station weights are expressed as the product of several weighting factors in the form of Gaussian functions in which the distances and the level of similarity between the station cells and the considered DEM grid cell in terms of orographic features are taken into account. In order to properly apply this procedure to the complex Italian domain, the coefficients regulating the decrease of the weighting factors are locally optimised by an iterative method. At each point of a 1°x1° resolution grid covering the study area, the normals of the stations in the range of 200 km are recursively computed and the optimal values of the coefficients are those which minimise the error estimators. Optimised coefficients are then estimated for the high-resolution grid interpolating the 1°x1° grid results by inverse distance weighting (IDW) and they are used to produce the climatologies. The performance of the model is evaluated by comparing, with a leave-one-out approach, the precipitation normals computed for each station to the corresponding observed values in terms of mean error (BIAS), mean absolute error (MAE) and root mean square error (RMSE). The results are then compared with those provided by other interpolation approaches, such as IDW and regression kriging (RK) with elevation as predictor. IDW exhibits the largest MAEs and RMSEs in any month (9.5 and 14.2 mm as monthly average), LWLR and RK are quite comparable in summer, while LWLR performs significantly better in winter. Mean monthly MAEs and RMSEs are 8 and 11.8 mm for LWLR, and 8.3 and 12 mm for RK. LWLR monthly precipitation maps show the finest spatial detail, nevertheless IDW and RK maps could be useful supports to detect and correct possible outliers in LWLR results
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
1961-1990 high-resolution monthly precipitation climatologies for Italy
Full text linkHigh-resolution monthly precipitation climatologies for Italy are presented. They are based on 1961-1990 monthly precipitation normals obtained from a quality-controlled observational dataset of about 6200 stations covering the whole Italian surface and part of the Northern neighbouring regions. The climatologies are computed by means of a weighted local linear regression of precipitation versus elevation: for each cell of a smoothed 30-arc second resolution grid the regression is performed considering the 15 stations with the highest weight. The station weights are expressed as the product of several weighting factors in the form of Gaussian functions in which the distances and the level of similarity between the station cells and the considered grid cell in terms of orographic features are taken into account. The performance of this approach is evaluated by comparing, with a leave-one-out approach, the precipitation normals computed for each station to the corresponding observed values in terms of mean error (BIAS), mean absolute error (MAE) and root mean square error (RMSE), both in absolute and relative form. In order to properly apply this procedure to the complex Italian domain, the coefficients regulating the decreasing of the weighting factors are locally optimised by an iterative method. At each point of a 1°x1° resolution grid covering the whole study area, the normals of the stations in the range of 200 km are recursively computed and the optimal values of the coefficients are those which minimise the error estimators. Optimised coefficients are then estimated for the high-resolution grid interpolating by inverse distance weighting (IDW) the 1°x1° grid results and they are used to produce the climatologies. This procedure allows to obtain lower errors than simpler approaches, such as IDW of the station normals: the MAE for reconstructed normals turns out to be about 8 mm corresponding to about 10% in relative terms
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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