1,721,109 research outputs found
Red de investigacion sobre la ictiofauna amazonica : 4° coloquio internacional RIIA : libro de resumenes = Research network on amazonian ichthyofauna : 4th RIIA international conference : book of abstracts
No full textProceedings of the 4th International Conference of the "Research Network on Amazonian Ichthyofauna" (RIIA) September 30 - October 2, 2014 Cochabamba, Bolivia
No full textThis study aimed at describing the normal bony skeleton of Pseudoplatystomapunctifer juveniles to use as a reference when assessing the adequacy of nutritional and environmental conditions in experimental rearing during the early developmental stages and to provide a baseline for characterizing skeletal anomalies that might appear in rearing trials with this species. Fertilized eggs and newly hatched P.punctifer larvae were incubated at 27.8 +/- 0.4 degrees C in two 60-L tanks (50-L water volume) connected to a clear water recirculating system. At 3days post fertilization - dpf (2days post hatching - dph) larvae were reared in three 40-L tanks (30-L water volume; initial n=2700 larvae per tank; 28.3 +/- 0.4 degrees C, pH 6.9 +/- 0.2, dissolved oxygen 8.2 +/- 0.5mgL(-1), N-NO2 0.04 +/- 0.02mgL(-1), N-NH4 0.14 +/- 0.05mgL(-1); 0L:24D photoperiod) and fed as follows: non-enriched Artemia spp. nauplii from 4 to 21 dpf (3-20 dph) and a commercial compound diet from 18 dpf onwards. Pseudoplatystomapunctifer juveniles (23.2 +/- 5.5mm standard length, SL, n=58) were stained with alizarin red and their skeletal structures analysed and identified under stereoscope. Pseudoplatystomapunctifer presents an osseous skeleton typical of catfishes, consisting of a broad and depressed skull containing small eyes, 43-44 vertebrae (44 being the most frequent), a caudal fin complex composed of one epural, five hypurals, one parhypural and two hypurapophyses, dorsal and pectoral fins with spines and anal and adipose fins. The observed occurrence of several skeletal anomalies indicates that the rearing conditions might have been suboptimal
Proceedings of the 4th International Conference of the "Research Network on Amazonian Ichthyofauna" (RIIA) September 30 - October 2, 2014 Cochabamba, Bolivia
No full textThe influence of three commercial diets with different protein and lipid contents (40:14, 45:8, 48:8 protein:lipid - P:L, in % dry weight of diet) on growth performance, survival and the histology of the liver and intestine was analysed in early juveniles of silver arowana, Osteoglossumbicirrhosum, reared in captivity. Individuals (initial wetweight-W-i=1.07 +/- 0.04g; total length-TL= 6.0 +/- 0.17cm) were raised in triplicate (n=12 fish per tank) at 26.2 +/- 0.1 degrees C and fed one of three commercial diets over 60days. At the end of the trial, survival (90.5 +/- 3.3%) and condition factor (0.5 +/- 0.02) were not affected by dietary treatments, whereas specific growth rate, TL and W gain were lower in animals fed the 40P:14L diet. Histological analysis revealed a larger accumulation of lipid droplets in the intestines of the group supplied with the 40P:14L diet, as well as a larger surface of hepatic lipid vacuoles compared to the other treatments, although no signs of steatosis were observed. Juveniles fed the 48P:8L diet displayed the lowest liver lipid accumulation; however, a protein content higher than 45% did not improve growth performance. The intestine and liver lipid accumulation of individuals fed the 45P:8L diet might indicate a more balanced lipidic metabolism. Intestine and liver histologies proved to be useful markers to identify the nutritional condition in juveniles of O.bicirrhosum, even when differences in nutritional composition were subtle (i.e. protein variation of 3%)
Red de investigacion sobre la ictiofauna amazonica : 4° coloquio internacional RIIA : libro de resumenes = Research network on amazonian ichthyofauna : 4th RIIA international conference : book of abstracts
No full text
Proceedings of the 4th International Conference of the "Research Network on Amazonian Ichthyofauna" (RIIA) September 30 - October 2, 2014 Cochabamba, Bolivia
No full textThe aim of this study was to compare the effects of dry and moist diets at weaning on growth, survival and incidence of cannibalism in the Amazon catfish Pseudoplatystoma punctifer. Three moist diets (MCD: moist commercial diet; MCPD: moist commercial peptide enriched diet; BLD: bovine liver enriched diet) and a dry diet (CDD: commercial dry diet) were used to feed fingerlings reared in 40-L tanks (30-L water volume; three replicates per treatment; stocking density: initial 1500 larvae per tank, from 18 days post-fertilization, dpf (17 days post-hatch, dph) onwards 210 juveniles per tank; photoperiod 0L:24D) in a recirculation water system (27.9 +/- 0.5 degrees C). Fish were fed Artemia nauplii at 20% of the larval biomass from 4 to 19days post-fertilization (dpf) and then weaned onto the four experimental diets within 3days in the moist diets and within 6days in the dry diet. At 33 dpf, feeding of groups fed the moist diets was switched to the dry diet within 2days. Results showed higher (58.6 +/- 10%) and lower (4.7 +/- 0.7%) survival rates in BLD and CDD groups, respectively, the latter showing the highest occurrence of type II cannibalism. Although weaning was achieved in all dietary groups, the moist diets MCD and MCPD showed better growth results both in terms of total length and wet weight. This study showed that, among the tested diets, the moist diets seem to be more adequate for early juvenile P.punctifer
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
Red de investigacion sobre la ictiofauna amazonica : 4° coloquio internacional RIIA : libro de resumenes = Research network on amazonian ichthyofauna : 4th RIIA international conference : book of abstracts
No full text- …
