1,720,964 research outputs found
Rilievi immunoistochimici e batteriologici sul tessuto muscolare di bovini affetti da Pleuropolmonite contagiosa bovina (PPCB)
No full textThe muscular tissue of 42 cattle affected by contagious bovine pleuropneumonia (CBPP) has been examined bacteriologically and immunohistochemically for the presence of Mycoplasma mycoides subsp. mycoides. All cases were bacteriologycally negative. The presence of M.mycoides was immunohistochemically detectable in 16 cases. On the basis of our results, pathogenetical and meat inspection aspects are discusse
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
Histological and immunohistochemical findings in thoracic lymph nodes of cattle with contagious bovine pleuropneumonia (CBPP).
No full textHISTOLOGICAL AND IMMUNOHISTOCHEMICAL FINDINGS IN THORACIC LYMPH NODES OF CATTLE WITH CONTAGIOUS BOVINE PLEUROPNEUMONIA (CBPP)
E. Scanziani, S. Paltrinieri*, M. Boldini**, G. Mandelli, V. Grieco, C. Monaci**
Istituto di Anatomia Patologica Veterinaria e Patologia Aviare - Milano; * Istituto di Patologia Generale Veterinaria - Milano; ** Istituto Zooprofilattico Sperimentale della Lombardia e dell’Emilia - Brescia
Introduction
Since the 1550 the contagious bovine pleuropneumonia (CBPP) spred all of the world. The prophilaxis and the increasing knowledges of the aetiology and the pathogenesis of the disease led to a decrease of the prevalence of the CBPP with a complete eradication from many countries: it was eradicated from the USA in 1982 and from Australia in 1967. In this century the CBPP was confined in some endemic african countries. In Europe some outbreaks of this disease occured in 1958 in Portugal (Ferronha et al. 1990) and between 1980 and 1984 in Spain, Portugal and France. At the end of 1990 the CBPP has been diagnosed in Lombardy, Northern Italy (Guadagnini et al., 1991). The clinico-pathological findings of CBPP are not specific: similar patterns of fibrinous pleuropneumonia are detectable in diseases such as the IBR, non specific mycoplasmosis etc... (Mandelli, 1989). The isolation and identification of Mycoplasma mycoides subsp. mycoides from infected animals is the only one reliable diagnostic test, but have many methodological problems (Al Aubaidi and Fabricant, 1970 Cottral 1978). Serological diagnosis is hampered either by false positive cattles due to cross-reactivity between Mycoplasma mycoides subsp. mycoides and other mycoplasmas or false negative animals in early and late phases of the disease.
Recently Mycoplasma mycoides subsp. mycoides antigen has been detected in the tissues by immunofluorescence (Ferronha et al., 1988) and immunohistochemistry (Ferronha et al. 1990; Scanziani et al. 1991a; Scanziani et al., 1991b): the localisation and the pattern of the positivity was variable with the evolutive step of the disease: in the acute phase antigens were detectable in alveolar macrophages as well as in the interlobular septa where a diffuse and weak positivity was found; with chronicity a strong positivity was found in the macrophages of fibrotic septa and in the follicular center of the broncho-alveolar associated lymphoid tissue (BALT). Necrotic debris in sequestra as well as the macrophages on their walls were strongly positive (Scanziani et al., 1991).
The lymph nodes only in the acute cases show gross pathological lesions: lymphoid hyperplasia and ectasia of the sinuses with a large number of macrophages were histologically detectable in the acute cases, while follicular hyperplasia with a large germinal center and fibrosis were present with chronicity. Large necrosis are rarely detectable: most frequently histology showed necrotic debris in the sinuses. In preliminary studies we detected Mycoplasma mycoides subsp. mycoides antigens in the lymph nodes (Scanziani et al. 1991a; Scanziani et al., 1991b)
The present work was assesed to study histological lesions and to detect the presence and localization of Mycoplasma mycoides subsp. mycoides antigens in thoracic lymph nodes of cattle affected by CBPP and to compare the results with bacteriological and serological positivity.
Matherial and methods
Animals
For the present study XX adult Holstein-Freisian cattle at slaughtering were selected. They came from 5 dairy herds on wich CBPP were present. All the animals were affected by CBPP: the diagnosis was based on the presence of tipical lung lesions and on the isolation of M.mycoides from the lungs.
For each animal macroscopic lesions of the lungs and thoracic lymph nodes were recorded at slaughtering. Furthermore the lungs and the thoracic lymph nodes were sampled for bacteriological and histological analysis. On the basis of macroscopic and histological lesions of the lungs each case was classified as acute, subacute or chronic. The thoracic lymph nodes of five cattle that had no pulmnary lesions, that were bacteriologically negative for M.mycoides and belonged to herds in which CBPP was not present were also sampled as controls.
Serology
Bacteriology
Coltural examination for mycoplasma was carried ut by plating on Difco PPLO agar (Difco----) medium supplemented with horse serum (xx per cent), yest extract (yy per cent), glucose, tallium acetate and penicillin. In addition the samples were homogeneized (10 per cent w/v) in Difco PPLO broth supplemented as for the solid medium. Three serial 10-fold dilutions were then made in the medium and subcultured on the solid medium after two days (?). The isolated mycoplasma were identified by biochamical tests, growth inhibition test and direct immunofluorescence.
Histology and immunohistochemistry
The samples of the lungs and of the thoracic lymhp nodes were fixed in 10% formalin and routinely embedded in paraffin. 5mm thick sections were then stained with haematoxilin and eosin and withthe avidin-biotin-peroxidase complex (ABC) procedure (Hsu et al. 1981), using commercial immunoperoxidase kits (Vectastain Elite; Vector Laboratories): sections were deparafiined, treated with 0,5 per cent hydrogen peroxide in methanol for 20 minutes, and rehydrated. They were then incubated at 4°C for 18 hours with a 1:20000 dilution of a policlonal rabbit antiserum against M. mycoides subsp. mycoides (kindly provided by Prof. M.C.D. De Lage of the Laboratorio Nazionale della Ricerca Veterinaria of Lisbona). After washing, the secions were covered with a secondary antibody biotinylated goat anti-rabbit immunoglobulin, and left at room temperature for 30 minutes. The peroxidase-conjugate ABC was allowed to react at room temperature for 30 minutes. Sectins were incubated with diaminobenzidine-hydrogen peroxide for seven minutes, washed in tap water and counterstained with Mayer’s haematoxilin. For each sample a negative control was made by replacing the primary antibody with normal rabbit serum. Known negative and positive control sections were included in each assay.
Results
Pathological findings
All the animals showed typical macrscopic lesions of CBPP. 13 animals had acute lung lesions with fibrinous interstitial pleuropneumonia with marmorization, mainly in the basal lobe, and lymph nodes were frequently affected, with enlarged (up than 10 times the normal size) and edematous lymph nodes and with a yellow coloured perilymphonodal fluid; 12 cases showed subacute lung lesions with a more evident marmorization of the acute lesions: thoracic lymph nodes tributaries of hte affected areas wererenlarged and slightly edematous; 28 animals had chronic lung lesions with sequestra and fibrosis: only some of this cases showed chronic lesions in the lymph nodesthat were moderately enlarged.
Lymph node histology
In the acute cases the marginal sinuses were ectasic and filled by lymph macrphages and granulocytes; macrophages were also detectable in the medullary sinuses.
In the subacute cases macrophages were presnt in the sinuses and mainly in the medullary sinuses: mild hyperplasia of the follicular germinal centers was also present in some cases
The germinal centers of the follicles was e
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
- …
