1,721,075 research outputs found
Per il profilo biografico e artistico del pittore fiammingo Jacob de Hase, maestro di Cerquozzi.
No full textRicordato dalle fonti di letteratura critica come artista di grande fama e primo maestro di Michelangelo Cerquozzi, Jacob de Hase, pittore d’Anversa che all’inizio del XVII secolo si trasferì a Roma, è ancora pressoché sconosciuto. Una sola opera è stata finora a lui attribuita: la Cattura di Cristo di collezione privata, firmata sulla lama di un soldato in primo piano. In questo studio, si analizza il testamento dell’artista, nel quale si citano alcune opere di sua esecuzione, e si propone l’attribuzione di un Martirio di San Bartolomeo (riportante una firma, di incerta lettura, sopra la lama di un aguzzino in primo piano). Inoltre, alcuni documenti inediti, rintracciati in diversi archivi romani, permettono di ricostruire l’attività economica del fiammingo, che per testamento distribuì ingentissime somme di denaro: parallelamente all’attività artistica (la sua bottega ospitò molti allievi-garzoni come Jan Snellinck e Antoon van Os), fu promotore di diversi investimenti finanziari, talora in società con illustrissime personalità come Federico Cesi.Jacob was born and trained in Antwerp, but at the beginning of the 17th century he moved to Rome where he lived for more than thirty years until his death. He is remembered by sources of critical literature as an artist of great fame and first master of Michelangelo Cerquozzi, but little is known of him yet. Only one work has so far been attributed to him: Capture of Christ from a private collection, signed on the blade of a soldier in the foreground. In the artist's will, analized in this study, some works of art executed by him are mentioned, although none are known yet. In this regard, the present study proposes the attribution to Jacob of a Martyrdom of Saint Bartholomew (bearing a signature, of uncertain reading, above the blade of a persecutor in the foreground). In addition, some unpublished documents, found in various Roman archives, allow us to reconstruct the economic activity of the Flemish, who by his will distributed huge sums of money: in parallel with the artistic activity (his workshop hosted many pupils-apprentices such as Jan Snellinck and Antoon van Os), he was the promoter of various financial investments, sometimes in partnership with illustrious personalities such as Federico Cesi
La discrezione di Chieppio, la baldanza di Rubens
No full textAbile e discreto segretario di Stato, Annibale Chieppio ebbe la funzione di mediatore tra il duca Vincenzo Gonzaga e il pittore Pietro Paolo Rubens durante gli otto anni di soggiorno italiano del fiammingo. Il saggio ricostruisce il rapporto tra il funzionario mantovano e il maestro d'Anversa attraverso la lettura di documenti editi e inediti, rivelando l'abilità diplomatica dell'uomo di Stato e la scaltrezza dell'artista, proponendo ipotesi sul contesto storico delle missioni che il duca affidò al giovane fiammingo per tramite del suo discreto segretario.An able and discreet secretary of state, Annibale Chieppio acted as mediator between Duke Vincenzo Gonzaga and the painter Pietro Paolo Rubens during the Flemish artist's eight-year stay in Italy. The essay reconstructs the relationship between the Mantuan functionary and the Antwerp master through the reading of published and unpublished documents, revealing the statesman's diplomatic skill and the artist's shrewdness, proposing hypotheses on the historical context of the missions that the duke entrusted to the young Flemish through his discreet secretary
Peter Paul Rubens e gli arciduchi delle Fiandre meridionali: storia di una committenza attraverso la ricostruzione documentaristica e iconografica delle collezioni della corte di Bruxelles
Full text linkNella lunga e fortunata carriera di Peter Paul Rubens, un ruolo fondamentale fu determinato dal rapporto che ebbe con gli arciduchi Alberto VII d’Asburgo e l’Infanta Isabella Clara Eugenia, divenuti governatori delle Fiandre meridionali, sotto l’egida del re di Spagna, di cui fu pittore di corte, agente d’arte, consigliere politico e ambasciatore. Tutte queste circostanze costituiscono la premessa fondamentale di questo studio, che ha per obiettivo l’indagine sistematica della produzione rubensiana commissionata dalla corte di Bruxelles durante gli anni di governo di Alberto VII e Isabella di Spagna. In particolare, l’analisi stilistica e iconografica è stata interpretata secondo i criteri di una precisa volontà di propaganda diplomatica volta a supportare le scelte politiche degli arciduchi, legati alla corte spagnola e, quindi, aderenti alla spiritualità controriformistica dettata dalla Chiesa, ma d’altro canto impegnati nella lotta contro i tentativi di conquista territoriale da parte delle rivoltose Fiandre settentrionali, riunite della neonata e indipendente Repubblica delle Provincie Unite. Il rinvenimento di alcuni importanti documenti archivistici ha inoltre contribuito a conoscere meglio un periodo poco noto nella biografia di Rubens, ossia gli anni italiani, chiarificando l’ambiente intellettuale fortemente cattolico frequentato dal pittore fin dagli anni giovanili, che indubbiamente costituì una fondamentale agevolazione per il suo ingresso alla corte fiamminga una volta tornato in patria
Differential effect of calsequestrin ablation on structure and function of fast and slow twitch skeletal fibers.
No full textWe compared structure and function of EDL and Soleus muscles in adult (4-6 m) mice lacking both Calsequestrin (CASQ) isoforms, the main SR Ca2+-binding proteins. Lack of CASQ induced ultrastructural alterations in ~30% of Soleus fibers, but not in EDL. Twitch time parameters were prolonged in both muscles, although tension was not reduced. However, when stimulated for 2 sec at 100 hz, Soleus was able to sustain contraction, while in EDL active tension declined by 70-80%. The results presented in this paper unmask a differential effect of CASQ1&2 ablation in fast versus slow fibers. CASQ is essential in EDL to provide large amount of Ca2+ released from the SR during tetanic stimulation. In contrast, Soleus deals much better with lack of CASQ because slow fibers require lower Ca2+ amounts and slower cycling to function properly. Nevertheless, Soleus suffers more severe structural damage, possibly because SR Ca2+ leak is more pronounced
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
Structural Adaptation of the Excitation–Contraction Coupling Apparatus in Calsequestrin1-Null Mice during Postnatal Development
Full text linkThe precise arrangement and peculiar interaction of transverse tubule (T-tubule) and sarcoplasmic reticulum (SR) membranes efficiently guarantee adequate contractile properties of skeletal muscle fibers. Fast muscle fibers from mice lacking calsequestrin 1 (CASQ1) are characterized by the profound ultrastructural remodeling of T-tubule/SR junctions. This study investigates the role of CASQ1, an essential component of calcium release units (CRUs), in the postnatal development of muscle fibers. By using CASQ1-knockout mice, we examined the maturation of CRUs and the involvement of different junctional proteins in the juxtaposition of the membrane system. Our morphological investigation of both wild-type (WT) and CASQ1-null extensor digitorum longus (EDL) fibers, from 1 week to 4 months of age, yielded noteworthy findings. Firstly, we observed that the absence of CASQ1 hindered the full maturation of CRUs, despite the correct localization of key junctional components (ryanodine receptor, dihydropyridine receptor, and triadin) to the junctional SR in adult animals. Furthermore, analysis of protein expression profiles related to T-tubule biogenesis and organization (junctophilin 1, amphiphysin 2, caveolin 3, and mitsugumin 29) demonstrated delayed progression in their expression during postnatal development in the absence of CASQ1, suggesting the impaired maturation of CRUs. The absence of CASQ1 directly impacts the proper assembly of CRUs during development and influences the expression and coordination of other proteins involved in T-tubule biogenesis and organization
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
Lessons from calsequestrin-1 ablation in vivo: much more than a Ca2+ buffer after all
No full textCalsequestrin type-1 (CASQ1), the main sarcoplasmic reticulum (SR) Ca(2+) binding protein, plays a dual role in skeletal fibers: a) it provides a large pool of rapidly-releasable Ca(2+) during excitation-contraction (EC) coupling; and b) it modulates the activity of ryanodine receptors (RYRs), the SR Ca(2+) release channels. We have generated a mouse lacking CASQ1 in order to further characterize the role of CASQ1 in skeletal muscle. Contrary to initial expectations, CASQ1 ablation is compatible with normal motor activity, in spite of moderate muscle atrophy. However, CASQ1 deficiency results in profound remodeling of the EC coupling apparatus: shrinkage of junctional SR lumen; proliferation of SR/transverse-tubule contacts; and increased density of RYRs. While force development during a twitch is preserved, it is nevertheless characterized by a prolonged time course, likely reflecting impaired Ca(2+) re-uptake by the SR. Finally, lack of CASQ1 also results in increased rate of SR Ca(2+) depletion and inability of muscle to sustain tension during a prolonged tetani. All modifications are more pronounced (or only found) in fast-twitch extensor digitorum longus muscle compared to slow-twitch soleus muscle, likely because the latter expresses higher amounts of calsequestrin type-2 (CASQ2). Surprisingly, male CASQ1-null mice also exhibit a marked increased rate of spontaneous mortality suggestive of a stress-induced phenotype. Consistent with this idea, CASQ1-null mice exhibit an increased susceptibility to undergo a hypermetabolic syndrome characterized by whole body contractures, rhabdomyolysis, hyperthermia and sudden death in response to halothane- and heat-exposure, a phenotype remarkably similar to human malignant hyperthermia and environmental heat-stroke. The latter findings validate the CASQ1 gene as a candidate for linkage analysis in human muscle disorders
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