1,721,060 research outputs found
Coi re magi e con le stelle
No full textCoi re magi e con le stelle / Francesco Sapori. - [S. l.] : Società editrice di Novissima, stampa 1935
Dedica manoscritta dell\u27autore: Alle loro Eccellenze / Emilio e Nina Bodrero, / tutti i cari augurii dell\u27amico: / Francesco Sapori / ROMA, 1934 : A XIII
https://galileodiscovery.unipd.it/discovery/fulldisplay?context=L&vid=39UPD_INST:VU1&search_scope=MyInst_and_CI&tab=Everything&docid=alma99001019453020604
L’«Adorazione dei Magi» e il suo cartone della Pinacoteca Vaticana
No full textIl saggio è incentrato sulla Adorazione dei magi e il suo cartone della Pinacoteca Vaticana, già attribuiti a Raffaellino del Colle e ora a Giorgio Vasari e bottega negli anni Quaranta del '500
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
Thiol-functionalized magnetic nanoparticles for static and dynamic removal of Pb(II) ions from waters
No full textThe synthesis of magnetite (Fe 3 O 4 ) nanoparticles (NPs) and the functionalization by means of a silane derivative (3-mercaptopropyl) trimethoxysilane (MPTMS) as a way for heavy metal capture, i.e., Pb 2+ ions, has been investigated. A direct reaction between the active thiol organosilane molecule and the surface of the magnetite nanoparticle is described. The coated nanoparticles, presenting an average diameter of about 20 nm, have been extensively characterized from the morphological, chemical, and physical point of view. The capture of Pb 2+ ions from aqueous solution has been performed both in static and dynamic mode, using in both cases a configuration of commercial NdFeB permanent magnets. The amount of heavy metal captured by the magnetic NPs as a function of time, as well as its fraction recovered by an EDTA solution, have been measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). The Pb 2+ capture from a spiked water solution (5 mg/L) is very fast, reaching 91% in static conditions after only 10 min. Furthermore, dynamic data also demonstrated the possibility to apply the toxic heavy metal capture method to large volumes
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
Phytoestrogens in soy-based meat substitutes: comparison of different extraction methods for the subsequent analysis by liquid chromatography-tandem mass spectrometry
No full textThis paper presents the development of an efficient extraction procedure followed by a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/ MS) method for the determination of five phytoestrogens (genistein, daidzein, formononetin, biochanin A, and coumestrol) in soy-based meat substitutes. Phytoestrogens are considered endocrine disrupting compounds, and their quantification is important in soy-based products, whose diffusion is increasing nowadays. The HPLC-MS/MS method, with electrospray ionization (ESI) source, was optimized to obtain high specificity and sensitivity, as well as rapidity of the analysis. Three extraction techniques were applied to soy burgers and compared: ultrasound assisted extraction, ultrasound assisted extraction followed by solid phase extraction and the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) methodology. Both ultrasound assisted extraction and QuEChERS proved to be suitable for the determination of phytoestrogens, showing high recoveries, in the range of 86% to 99% and 75% to 105%, respectively. Matrix effect was evaluated, and ion suppression was observed for coumestrol and formononetin, demonstrating the importance of matrix effect assessment when complex samples are analyzed by HPLC-ESI-MS. The complete analytical protocols provided limits of detection and quantitation in soy-burgers at the ng g−1 level for all the considered phytoestrogens. Some soy burger samples were analyzed by both ultrasound assisted extraction and QuEChERS followed by HPLC-MS/MS. High concentration levels of daidzein and genistein (2-59 μgg−1 and 2- 72 μg g−1, respectively) were found; formononetin was in the range of 5 to 26 ng g−1, while biochanin A and coumestrol were under the limit of quantitation in all samples. The results obtained with the two different sample treatment were in good agreement, proving the precision and accuracy of the described techniques
Determination of cadmium(II), copper(II), manganese(II) and nickel(II) species in Antarctic seawater with complexing resins
Full text linkThe strong species of cadmium(II), copper(II), manganese(II) and nickel(II) in an Antarctic seawater sample are investigated by a method based on the sorption of metal ions on complexing resins. The resins compete with the ligands present in the sample to combine with the metal ions. Two resins with different adsorbing strengths were used. Very stable metal complexes were investigated with the strong sorbent Chelex 100 and weaker species with the less strong resin, Amberlite CG-50. Strong species were detected for three of the considered metal ions, but not for Mn(II). Cu(II) is completely linked to species with a side reaction coefficient as high as log αM(I)=11.6 at pH=7.3. The ligand concentration was found to be similar to that of the metal ion, and the conditional stability constant was around 1020 M−1. In the considered sample, only a fraction of the metal ions Cd(II) and Ni(II) is bound to the strong ligands, with side reaction coefficients equal to log αM(I)=5.5 and 6.5 at pH=7.3 for Cd(II) and Ni(II), respectively. These findings were confirmed by the test with the weaker sorbent Amberlite G-50. It can be calculated from the sorption equilibria that neither Mn(II) nor Ni(II) is adsorbed on Amberlite CG-50 under the considered conditions and, in fact, only a negligible fraction of Mn(II) and Ni(II) was adsorbed. A noticeable fraction of Cd(II) was adsorbed on Amberlite CG-50, meaning that cadmium(II) is partially linked to weak ligands, possibly chloride, while no copper(II) was adsorbed on this resin, confirming that copper(II) is only combined in strong species. These results are similar, but not identical, to those obtained for other seawater samples examined in previous investigations
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
Investigation of the metal species in seawater by sorption of the metal ion on complexing resins with different sorbing properties
No full textThe distribution of some metal ions in seawater samples among different species was investigated by the resin titration (RT)
procedure, based on the separation of the metal ion on resins with different sorbing properties. Two complexing resins were
used for the titration of four metal ions (Cu(II), Cd(II), Ni(II) and Mn(II)): Amberlite CG 50 and Chelex 100. The first one is a
weak resin, able to sorb only the metal ion combined in weak complexes, or free, while Chelex 100 is a strongly sorbing resin,
able to sorb also the metal ion combined in strong complexes. The concentration of the total metal ion completely sorbed
and/or in equilibrium with the resin is obtained by RT. Also the reaction coefficient, i.e. the fraction of total to free metal ion
in the solution phase, in the presence of the resin, can be calculated. By comparing the titration with the two resins, three
groups of species for each metal ion can be detected. For each of these, the reaction coefficients are evaluated, or at least their
limiting values. For example, the complexes detected with Chelex 100 in the seawater samples here examined had very high
reaction coefficients: in the case of copper in one Ligurian Sea sample at pH = 7.1, log α(M(I)) = 9.7 was found, for a complex
concentration corresponding to 62% of the total metal ion. The rest of Cu(II) was linked to complexes with log α(M(I)) near to
1, weak enough to be dissociated and sorbed on Amberlite CG 50. The proportion of the groups of complexes was different in
the different samples examined, while the reaction coefficients were similar
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