1,720,961 research outputs found
Milk coagulation ability of Rendena and Holstein-Friesian cattle breeds
Full text linkAim of this study was to compare Holstein-Friesian (HF) and Rendena (RE) cattle breeds for milk coagulation and composition traits predicted by mid-infrared spectroscopy using official milk recording samples of 28 single-breed dairy herds of northeast Italy. Individual milk samples (n = 3,622) from 1,786 cows were analyzed for rennet coagulation time (RCT, min), curd firmness (a30, mm), and composition traits. A linear mixed model was used to study the effect of breed and environmental factors on RCT and a30. Breed was the most important source of variation for coagulation traits. In particular, milk from RE coagulated earlier and showed a firmer curd than milk from HF cows. Rennet coagulation time was shortest at the beginning of lactation, and a30 was better at the beginning and end of lactation. In conclusion, RE produced milk more suitable for cheese processing than that of HF. Clotting characteristics of RE breed should be considered when developing strategies useful for the valorization of this local genetic resource
Heritability of milk β-hydroxybutyrate and its genetic association with milk yield and fat-to-protein ratio in Italian Holstein cows
No full textA comparison of milk clotting characteristics and quality traits of Rendena and Holstein-Friesian cows
No full textMilk coagulation properties (MCP) and composition, as predicted by mid-infrared spectroscopy (MIRS), were compared between Rendena (RE) local breed and Holstein- Friesian (HF) cows using 4614 individual milk samples from 28 single-breed herds. Records of rennet coagulation time (RCT, min), curd firmness (a30, mm), daily milk yield and quality traits were analysed using a linear mixed model which included fixed effects of breed, herd-test-date nested within breed, lactation stage, parity, and two-way interactions between the main effects. Random effects were cow nested within breed and residual. Milk from RE coagulated 2.1 min earlier and showed a firmer curd by 4.8 mm than that of HF cows (P<0.05). Milk yield (+9.7 kg/d) and fat content (+0.22 g/100 g) were greater for HF than RE (P<0.05), while protein (+0.05 g/100 g) and casein (+0.06 g/100 g) contents were greater in milk from RE cows (P<0.05). Rennet coagulation time was shortest at the beginning of lactation, and a30 was firmest at the beginning and end of lactation. Results from this study suggest that milk of RE is more suitable for cheese processing than that of HF cows. Milk clotting characteristics of the local breed should be taken into account when developing strategies useful for its valorisation
Effect of microparticulated whey proteins on milk coagulation properties
Full text linkThe enhancement of milk coagulation properties (MCP) and the reuse of whey produced by the dairy industry are of great interest to improve the efficiency of the cheese-making process. Native whey proteins (WP) can be aggregated and denatured to obtain colloidal microparticulated WP (MWP). The objective of this study was to assess the effect of MWP on MCP; namely, rennet coagulation time (RCT), curd-firming time, and curd firmness 30 min after rennet addition. Six concentrations of MWP (vol/vol; 1.5, 3.0, 4.5, 6.0, 7.5, and 9.0%) were added to 3 bulk milk samples (collected and analyzed during 3 d), and a sample without MWP was used as control. Within each day of analysis, 6 replicates of MCP for each treatment were obtained, changing the position of the treatment in the rack. For control samples, 2 replicates per day were performed. In addition to MCP, WP fractions were measured on each treatment during the 3 d of analysis. Milk coagulation properties were measured on 144 samples by using a Formagraph (Foss Electric, Hillerod, Denmark). Increasing the amount of MWP added to milk led to a longer RCT. In particular, significant differences were found between RCT of the control samples (13.5 min) and RCT of samples with 3.0% (14.6 min) or more MWP. A similar trend was observed for curd-firming time, which was shortest in the control samples and longest in samples with 9.0% MWP (21.4 min). No significant differences were detected for curd firmness at 30 min across concentrations of MWP. Adjustments in cheese processing should be made when recycling MWP, in particular during the coagulation process, by prolonging the time of rennet activity before cutting the curd
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
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