1,720,957 research outputs found
Ricerca e identificazione morfologica di Strongili broncopolmonari di cervo (Cervus elaphus hippelaphus) e bovino (Bos taurus) nella Regione Valle d’Aosta
Full text linkLe strongilosi broncopolmonari nei ruminanti domestici e selvatici sono sostenute da nematodi del genere Dictyocaulus spp, agenti eziologici della bronchite parassitaria e causa di importanti danni economici in diversi Paesi del mondo.
La conoscenza di questi parassiti, quindi, risulta fondamentale ai fini della salvaguardia del patrimonio zootecnico e faunistico; tuttavia la letteratura disponibile riguardo le strongilosi polmonari, in particolare nei ruminanti selvatici dell’arco alpino, risulta essere limitata.
Uno degli obiettivi di questo studio è, pertanto, quello di fornire un panorama sulla presenza delle strongilosi broncopolmonari nel bovino (Bos taurus) e nel cervo rosso (Cervus elaphus) su territorio nazionale e, in particolare nella Regione Valle d’Aosta. Per la ricerca di Strongili sono stati presi in esame i polmoni di 100 bovini di razza Valdostana e di 104 cervi rossi. I bovini sono risultati tutti negativi, mentre 23 cervi sono risultati positivi per la presenza di Strongili polmonari, con una prevalenza di infezione del 22%.
Altro punto cardine di questa ricerca è rappresentato dall’identificazione su base morfologica della specie di Strongilo rinvenuta nel cervo rosso. Per questo sono state effettuate le misure dei caratteri utili ai fini dell’identificazione morfologica e queste sono state confrontate, sia con la specie riconosciuta da tempo nel cervo rosso, Dictyocaulus eckerti, che con la nuova specie recentemente identificata in Polonia: Dictyocaulus cervi n. sp (Pyziel et al, 2017). Queste due specie si distinguono per le misure di diversi caratteri chiave per l’identificazione morfologica.
I risultati hanno messo in evidenza una corrispondenza tra i valori delle misure degli Strongili polmonari prelevati e quelle riportate per D. cervi, il che permette di avanzare l’ipotesi secondo cui questa specie sia presente anche in Italia.
Questo potrebbe rappresentare, quindi, il primo caso di identificazione di D. cervi n. sp. nel cervo in Italia e non fa altro che confermare la necessità di approfondire la ricerca di questi parassiti per risolvere l’annosa questione relativa alla loro tassonomia.
Nel tempo diversi studi hanno messo in discussione l’ipotesi secondo cui il cervo possa rappresentare un serbatoio di infezione per il bovino (Divina et al, 2000, Pyziel et al, 2015) e i risultati di questa ricerca forniscono un ulteriore supporto alla tesi secondo cui le strongilosi broncopolmonari siano ad eziologia specie-specifica e non via sia, in natura, la possibilità di cross-infezione.
Dai parassiti sono stati, inoltre, prelevati campioni da sottoporre a PCR, al fine di confermare o escludere l’ipotesi avanzata dall’indagine morfologica
Sarcoptic mange in wild carnivores and its co-occurrence with parasitic helminths in the Western Italian Alps
No full textBetween 2001 and 2004, 229 foxes, 36 stone martens and 48 badgers from the western Italian Alps were examined for sarcoptic mange and for gastrointestinal helminths to investigate their prevalence and geographical distribution and to point out the existence of potential interactions among them. Sarcoptic mange was observed in 25.3±2.8% SE of foxes and in 5.6±3.8% SE of stone martens, while no badger was found infected. Helminths belonged to Cestoidea Cyclophillidea (3.0±1.1% SE), Nematoda Trichurida (Capillaria aerophila and Trichuris vulpis: 6.5±1.6% SE; Trichinella britovi: 3.0±1.1% SE), Ascaridida (12.2±2.2% SE) and Strongylida (6.9±1.7% SE). Sarcoptic mange infection and the presence of helminths proved to be associated, with mangy foxes showing significantly higher prevalence of both cestode and nematode (particularly Ascaridida) worms. Moreover, considering three clusters of parasites (S. scabiei, nematodes and cestodes), more foxes than expected hosted simultaneously 2 and 3 taxa. These evidences suggest the existence of some kind of interaction, whose modalities and implications are discussed in this paper
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
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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