1,720,970 research outputs found
Response of European sea bass (Dicentrarchus labrax) to graded levels of methionine (total sulfur amino acids) in soya protein-based semi-purified diets
No full textThe dietary methionine (Met) and total sulfur amino acid (TSAA) requirements of European sea bass (Dicentrarchus labrax) (initial body weight 134 (sd 02) g) were estimated in a 12-week dose-response experiment. Seven isonitrogenous (76% DM) and isoenergetic (gross energy, 212MJ/kg DM) diets, based on soya protein and crystalline l-amino acids containing graded levels of l-Met (16-162g/kg) at a constant cysteine (4g/kg) level and a fish meal-based diet, were fed each to triplicate groups of fifty fish kept in 250 litre tanks in a thermoregulated (2305C) seawater system. The Met and TSAA-deficient diet resulted in higher mortality, impaired feed intake and growth relative to the other treatments (P<001). No signs of lens opacity due to limiting Met intake were observed and no feed intake or growth depression occurred at the highest level of dietary TSAA. Met and TSAA requirements for optimal N deposition or weight gain as fitted with the broken-line model resulted in estimated values of 80 and 120g/kg diet (for example, 18 and 27% dietary protein) and 91 and 131g/kg diet (for example, 20 and 30% dietary protein), respectively. Plasma levels of Met, homocysteine and cysteine increased in response to excess dietary TSAA, corroborating requirement estimates from growth data. N gain resulted in a linear function of TSAA consumption at marginal Met (TSAA) intake. The TSAA intake needed to maintain N balance resulted in a value of 200mg TSAA/kg average body weight 075 per d, which represents 23% of the total (maintenance+accretion) requirement
Response of sea bass to graded levels of total sulphur amino acids in semipurified diets
No full textWelfare and quality of farmed trout fed high plant protein diets. 1. Growth performance and quality traits.
No full textThis study was performed to evaluate the effects of high levels of inclusion of plant protein sources to replace fish
meal in rainbow trout (O. mykiss) diets on growth performance and quality characteristics. Two isoproteic (44.8%)
and isolipidic (19.6%) extruded diets were fed to eight groups of trout (IBW 106.6g) for 103 days. Diet FM, containing
only fish meal as protein source, was used as control treatment and compared to diet PV80, where a plant
protein mix (pea protein concentrate and wheat gluten) was included to replace 80% of fish meal protein. Growth
performance (FBW: 318.5g; SGR: 1.06%) and feed to gain ratio (0.79) of the fish were not affected by dietary treatment
(p>0.05). Dry matter and protein ADCs, measured in vivo after stripping, resulted higher in fish fed the high
vegetable protein diet relative to the fish meal one (p<0.05). Trout fed diet PV80 were characterised by higher agility
index (2.02 vs 1.72, p<0.05), carcass yield (91.95 vs 91.18%, p<0.05), lower hepatosomatic index (0.74 vs 1.07%,
p<0.05) and viscerosomatic index (8.04 vs 8.82%, p<0.05) but higher mesenteric fat index (3.08 vs 2.88%, p<0.05)
relative to FM fed trout. No significant effect was observed in terms of fillet yield (59.28 vs 6.41%, p<0.05). Feeding
diet PV80 resulted in a significant reduction of fillet pH 48h post mortem (5.56 vs 6.44, p<0.05) while no reduction
was observed in fillet of trout fed the FM diet (6.56, p>0.05). Higher dry matter (28.2 vs 26.8g/100g, p<0.01) and
hydroxyproline (0.79 vs 1.31mg/g, p<0.01) content as a measure of total collagen, was observed in fillets of trout fed
PV80 diet relative to the control ones. According to these data, also post mortem firmness measured by the Shear
force of raw muscle resulted higher in fish fed the plant protein based diet (4.06 vs 3.30N, p<0.05). The firmness
reduction observed 48h post mortem (4.24 vs 2.95N, p<0.05) resulted not affected by the dietary treatment.
In summary, data show that even if the growth performance of rainbow trout fed a diet in which fish meal was
largely replaced by high quality plant proteins resulted similar, some major quality traits such as dressing out, fillet
composition and texture can be significantly affected by dietary treatment
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
L'allevamento della sogliola (Solea solea): sintesi dei risultati ottenuti nello svezzamento ed accrescimento dei giovanili.
No full textViene illustrata una sintesi dei risultati conseguiti nell'ambito delle ricerche co-finanziate da ARSIA regione Toscana sull'allevamento di Solea solea con particolare riferimento agli effetti di alcune variabili gestionali sulla performance zootecnica nelle fasi di svezzamento e successivo accrescimento dei giovanili .
La sperimentazione ha avuto luogo presso gli impianti di Orbetello Pesca Lagunare s.r.l. (GR) ed ha utilizzato giovanili ottenuti da riproduzione controllata operata su scala pilota presso il medesimo impianto dal 1998.
Grazie alla tecnica del co-feeding e all'utilizzo di microdiete complete di nuova generazione, questa delicata fase dell'allevamento dei giovanili condotta a temperature comprese tra 16 e 22°C, ha consentito per la prima volta di ottenere tassi di crescita e sopravvivenza particolarmente incoraggianti. Già nella fase di svezzamento, la densità di confinamento rappresenta una delle variabili più importanti nel condizionare gli esiti dell'allevamento. Anche nelle successive fasi di allevamento dei giovanili svezzati la crescita è risultata densità-dipendente mentre la mortalità si è mantenuta a livelli trascurabili in assenza di gravi eventi patologici.
In regime termico controllato e con densità iniziali non superiori a 150 ind/m2 è possibile ottenere i primi soggetti di taglia minima commerciale (>100 g) dopo circa 600 giorni dalla schiusa con tassi di sopravvivenza elevati e densità finali pari al 200% di copertura della vasca. La sperimentazione ha consentito per la prima volta di concludere il ciclo di allevamento della sogliola con una produzione pilota di circa 0,4 T di soggetti di taglia commerciale a segnalare l'adattabilità della specie alle condizioni di allevamento intensivo e nuove opportunità di diversificazione delle produzioni per l'Acquacoltura marina toscana
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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