1,721,020 research outputs found
Lo studio delle funzioni esecutive nel ritardo mentale e nelle difficoltà di apprendimento
No full textStudio sperimentale del comportamento di un nuovo modello di opera stabilizzatrice del manto nevoso
No full textIl lavoro illustra i risultati sperimentali e numerici per lo studio di un nuovo tipo di opera stabilizzatrice del manto nevoso "ombrello da neve". La ricerca è stata sviluppata con una sperimentazione in vera grandezza nel corso della quale è stato monitorato il comportamento dell'ombrello da neve sollecitato dal manto nevoso per un intero inverno
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
Correlati neurofisiologici dell’empatia per il dolore
No full textIl dolore è una complessa esperienza soggettiva, spiacevole sia dal punto di vista sensoriale che da quello emotivo, e legata ad un danno reale o potenziale dell’organismo. Il dolore ha una valenza protettiva consentendo ad esempio la messa in atto di comportamenti di evitamento, ed in questo senso è strettamente legato al sistema motorio. L’esperienza del dolore consta di componenti discriminative sensoriali (e.g. valutazione della sede, della durata e dell’intensità della sensazione), distinte da quelle affettivo-motivazionali (analisi di spiacevolezza, fastidio, turbamento indotto dalla sensazione provata). L’esperienza del dolore è rappresentata in due grandi gruppi di strutture nervose, che nel loro insieme costituiscono la matrice per il dolore. Un gruppo è dedicato alla rappresentazione degli aspetti sensoriali, l’altro a quelli emozionali del dolore.
L’empatia implica che un dato stato percettivo, motorio o emozionale di un certo individuo attivi rappresesentazioni neurali corrispondenti in un altro individuo che osserva quello stato. Questo fenomeno ha un fondamentale ruolo sociale perche consente lo scambio inter-individuale di esperienze, credenze, scopi e stati interni. Le neuroscienze cognitive hanno affrontato il tema dell’empatia per il dolore solo molto recentemente. Il presente contributo si basa sulle principali ricerche sperimentali nell’uomo, riguardanti i correlati neurali dell’osservazione e dell’immaginazione, sia implicita che esplicita, del dolore altrui, con particolare riferimento al ruolo del sistema sensorimotorio. Si dimostrerà come la rappresentazione del dolore altrui implichi l’attivazione di molte delle strutture neurali chiamate in gioco durante il dolore provato in prima person
Biocompatibility and integrin-mediated adhesion of human osteoblasts to poly(DL-lactide-co-glycolide) copolymers
No full textThe biocompatibility of polylactic acid (PLA) and polyglycolic acid (PGA) copolymers, employed in manufacturing bone-graft substitutes, is affected by their chemical composition, molecular weight and cell environment, and by the methods of polymerization and processing. Their in vitro bioactivity on human osteoblasts has been investigated very little. We first evaluated the behavior of primary human osteoblasts cultured in close contact with 75:25 and 50:50 PLA-PGA copolymers for 14 days adopting a cell culture system that allowed us to evaluate the influence of direct contact, and of factors released from polymers. The copolymers had no negative influence on cell morphology, cell viability and proliferation. Alkaline phosphatase (ALP) activity and osteocalcin production were also not affected. The initial adhesion of osteoblasts on implant surfaces requires the contribution of integrins, acting as a primary mechanism regulating cell-extracellular matrix (ECM) interactions. We observed that adhesion of osteoblasts to PLA-PGA copolymers, 2h after plating, was reduced by approximately 70% by antibodies capable to block integrin beta(1) and alpha(5)beta(1) complex and only by approximately 30% by an anti-integrin alpha(v) antibody. Therefore, beta(1) integrins may represent a predominant adhesion receptor subfamily utilized by osteoblasts to adhere to PLA-PGA copolymers. These materials do not show any negative influence on cell proliferation and differentiation
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
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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