1,720,974 research outputs found
Prevalenza, qualità e frequenza dell’attività motoria praticata dagli studenti della Scuola Media di 1° grado in diverse realtà regionali italiane.
No full textViral production in the Gulf of Trieste (Northern Adriatic Sea): preliminary results using different methodological approaches.
No full textAlthough the temporal and spatial variability of virioplankton in the northernmost part of the Adriatic Sea
has been repeatedly explored suggesting that viruses constitute an extremely dynamic component of the
plankton community and hypothesizing their importance in marine food webs and mucilage events, there is
still no information about viral replication rates. Hence, the contribution of viruses to bacterial mortality and
the cycling of organic matter in this part of the Adriatic basin are still not fully comprehended. Assessment of
the role of viral lysis requires a robust means of estimating viral production. Since, up to now, none of the
available methods evolved to a state of a standard yet, in this preliminary study 3 different experimental
approaches were simultaneously assayed (viral production estimated by radiotracer incorporation method
[TdR], dilution technique for the estimate of viral production in already infected bacteria [DIL] and serial
dilution method in manipulated phage-host assemblage [SER]). The present study provided the first
evidence of viral production rates in this study area, that resulted in comprising between ∼3.5–15×108
viruses L−1 h−1 and critically faced up the results obtained by different techniques with the consideration
that they suffer from different biases. Based on TdR and DIL viral proliferation estimates, viral lysis was
responsible for the loss of 54 to 95% of the bacterial standing stock, while the viral-induced mortality by SER
(325%d−1) was likely consistently overestimated. These results indicate that viral lysis is a significant factor
for prokaryotic mortality suggesting its implication as an important pathway for the cycling of dissolved
organic matter in the Gulf of Trieste
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
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
Attività batterica all’interfaccia acqua-sedimento in una stazione costiera del Golfo di Trieste. Biol Mar Medit
No full textOrganic matter degradative potential of Halomonas glaciei isolated from frazil ice in the Ross Sea (Antarctica)
No full textLarge-scale spatial distribution of virioplankton in the adriatic sea: Testing the trophic state control hypothesis
No full textLittle is known concerning environmental factors that may control the distribution of virioplankton on large spatial scales. In previous studies workers reported high viral levels in eutrophic systems and suggested that the trophic state is a possible driving force controlling the spatial distribution of viruses. In order to test this hypothesis, we determined the distribution of viral abundance and bacterial abundance and the virus-to-bacterium ratio in a wide area covering the entire Adriatic basin (Mediterranean Sea). To gather additional information on factors controlling viral distribution on a large scale, functional microbial parameters (exoenzymatic activities, bacterial production and turnover) were related to trophic gradients. At large spatial scales, viral distribution was independent of autotrophic biomass and all other environmental parameters. We concluded that in contrast to what was previously hypothesized, changing trophic conditions do not directly affect virioplankton distribution. Since virus distribution was coupled with bacterial turnover times, our results suggest that viral abundance depends on bacterial activity and on host cell abundance
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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