1,721,079 research outputs found
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
Role of Stress-Related Dopamine Transmission in Building and Maintaining a Protective Cognitive Reserve
No full textThis short review presents the hypothesis that stress-dependent dopamine (DA) transmission contributes to developing and maintaining the brain network supporting a cognitive reserve. Research has shown that people with a greater cognitive reserve are better able to avoid symptoms of degenerative brain changes. The paper will review evidence that: (1) successful adaptation to stres-sors involves development and stabilization of effective but flexible coping strategies; (2) this process requires dynamic reorganization of functional networks in the adult brain; (3) DA transmission is amongst the principal mediators of this process; (4) age-and disease-dependent cognitive impairment is associated with dysfunctional connectivity both between and within these same networks as well as with reduced DA transmission
k-dense Communities in the Internet AS-Level Topology Graph
No full textExtracting a set of well connected subgraphs as communities from the Internet
AS-level topology graph is crucially important for assessing the performance
of protocols and routing algorithms, for designing ecient networks, and for
evaluating the impact of failures. In addition, these dense zones of the Internet
AS-level topology graph enable to individuate which business classes of ASs are
interested in interconnecting with each other. A huge number of community
extraction algorithms have been proposed in the literature, including the k-
core decomposition and the k-dense community detection algorithms. Both
algorithms are computationally ecient, however the k-dense is able to discover
more well-connected communities.
In this paper we investigate the structure of the Internet by exploiting an ecient
algorithm for extracting k-dense communities from the Internet AS-level topology
graph.The analyses showed that the most well-connected communities consist of
a small number of ASs characterized by a high level of clusterization, although
they tend to direct a lot of their connections to ASs outside the community.
In addition these communities are mainly composed of ASs that participate at
the Internet Exchange Points (IXPs) and have a worldwide geographical scope.
Regarding k-max-dense ASs we found that they play a primary role in the Internet
connectivity since they are involved in a huge number of Internet connections
(42% of Internet connections). We also investigated the properties of three classes
of k-max-dense ASs: Content Delivery Networks, Internet Backbone Providers
and Tier-1. Specically, we showed that CDNs and IBPs heavily exploit IXPs
by participating in many of them and connecting to many IXP participant ASs.
On the other hand, we found that a high percentage of connections originated by
Tier-1 ASs are likely to involve national ASs which do not participate at IXPs
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
Paesaggio e rappresentazione di aree archeologiche in una valle andina (Chacas – Perù)
No full textIl lavoro illustra alcuni dei risultati ottenuti durante i rilievi archeologici eseguiti nell'area della Valle di Chacas (Ancash- Perù) a partire dal 1996. Nel contesto di tali studi, al tradizionale rilievo è stato associato il rilievo topografico e fotogrammetrico delle strutture presenti volto anche a rappresentare i principali caratteri morfologici dell'area. L'analisi integrata delle informazioni raccolte consente da una parte di documentare i resti degli insediamenti e gli oggetti rinvenuti attraverso tecniche topografiche rigorose e dall'altra di indagare il rapporto esistente tra uomo e ambiente nelle aree andine in funzione dei diversi piani ecologici individuati
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