1,721,026 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Fish Farm Inspections and Sampling Procedures: The Mediterranean Point of View
Get PDFMarine Mediterranean aquaculture meant as intesive rearing system for zootechnical production has known a recent development extremely fast.The development of efficacious breeding protocols, the availability of artificial feeding more and more efficient and some principles adopted in facing diseases have lead the growth of an industrial rearing system.If we consider the health management approach within the context of this this complex productive scenario there is the need to discriminate between, at least, two main different groups of farms that are extremely different and caracterised by peculiar health/disease management issues.First of all there are to be considered the hatcheries, this kind of farm are caracterised by having an extremely high level of technology and control of the water that; in these system biosecurity measures are generally high and the water quality parameters are kept monitored constantly.Secondly there are to be considered all the farms that undergo to the category of “ongrowing”. These kind of rearing activities, once obtained the seed / juveniles provide them feeding till the juveniles have reached the market size. Within this group sea cages have affirmed as the best ones both for economical and technological/environmental aspects.Sanitary issues to be managed, their evolution, related control strategies and analytical tools are, in this complex, quite different but all are linked to a common data: they are part of a framework that need to be considered firstly.In this presentation, mainly based on pictures, different aspects of clinical inspection/sampling protocols are described
ANALISI ISTOPATOLOGICA E BIOMOLECOLARE DELLA WINTER DISEASE in SPARUS AURATA
Get PDFGilthead sea bream Sparus aurata is one of the most important fish reared in coastal lagoon with ”valliculture” in the Mediterranean area. During cold periods it is affected by a metabolic syndrome termed “Winter disease” which causes a mortality rate reaching, in some cases, 60% in the North of
Italy.An experiment was conduct to analyse the adaptative response to low temperatures using three kind of analysis techniques. This experimental trial was based on a case-control scheme. Seabreams were divided into two main groups: seabreams in the “case” tank were exposed to low temperature, whereas for those in the “control” tank temperature was constantly warm. Tissue samplings were
carried out through acute and chronic phase. A first analysis with Microarray technology was performed to reveal the differences of gene expression between fish reared at low temperature and controls. Secondly was performed Real-Time
RT-PCR to validate Microarray results and evaluate the differences of gene expression during the experiment. Lastly were evaluate histological analysis of the skin and the cephalic kidney samples during the experimental protocol, and other tissues such as gill, liver, spleen and kidney were collected and analysed after a recovery phase at the end of the experiment. Biomolecular analysis demonstrates that there is an up-regulation of genes belonging to pathways
such as energetic metabolism and lipid metabolism in liver and a down-regulation of genes belonging to immunitary response. In gills up-regulated genes belong to very different pathways involved in apoptosis, ROS scavenger and lipidic methabolism, moreover down-regulated genes belong to the immunitary response pathway. Histopatological analysis demonstrate a different distribution of melanomacrophage centres in cephalic kidney and a greater severity of lesions
affecting fish exposed to low temperature. It is the first time that cold response was analysed with both biomolecular and histological techniques in Sparus aurata to understand the aetiopathogenesis of Winter Stress Syndrome
Piscine orthoreovirus: Distribution, characterization and experimental infections in salmonids
Get PDFPiscine orthoreovirus (PRV) belongs to the family Reoviridae and is most closely related to the genus Orthoreovirus. Piscine orthoreovirus are causative agents of emerging diseases for salmonid aquaculture worldwide. This viral species currently counts three different subtypes, each one with preferential host. PRV-1 is the causative agent of heart and skeletal muscle inflammation (HSMI) in Atlantic salmon (Salmo salar) and is associated with jaundice syndrome in farmed Chinook salmon (Oncorhynchus tshawytscha). PRV-2 causes erythrocytic inclusion body syndrome (EIBS) in Coho salmon (Oncorhynchus kisutch). PRV-3 causes heart pathology resembling HSMI in Rainbow trout (Onchorynchus mykiss). In Europe only PRV-1 and PRV-3 are present PRV-3 was firstly discovered in 2013 in Norway during disease outbreaks affecting farmed Rainbow trout. The first series of experimental trials were performed to assess its pathogenicity and pathogenesis in Rainbow trout and Atlantic salmon.The Norwegian PRV-3 isolate has been further characterized analyzing its genome and antigenic features. An experimental infection study with purified virus demonstrated that PRV-3 infection in Rainbow trout induces pathological heart lesions similar to HSMI, and thus fulfil causative relationship. Furthermore, the infection upregulates IFN production and induces a specific antibodyresponse in later phases. In late 2017 the presence of PRV-3 was also reported in different countries in Europe including Scotland, Germany, France, Italy and Denmark. Interestingly, these viral isolates appear to be genetically distinct from the Norwegian isolate leading to the proposition of two separate clades within PRV-3 viral type (PRV-3a and PRV-3b). PRV-1 is prevalent in farmed Atlantic salmon in sea water in Europe. The prevalence of the virus has been investigated in wild salmon stocks to expand the knowledge of its epidemiology. PRV can induce a systemic antiviral immune response, which may affect the outcome of a secondary virus infection. Infectious haematopoietic necrosis virus (IHNV) causes major challenges to the Atlantic salmon industry in Canada, requiring the implementation of DNA vaccination to control the disease. IHNV is not present in Atlantic salmon farmed in Europe and feared as a major risk for the aquaculture industry, and therefore we have assessed the potential interaction of these two pathogens in Atlantic salmon in the co-challenge trial
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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