1,721,058 research outputs found
The Unique Crystallization Behavior of Buffalo Milk Fat
No full textA full comprehension of milk fat crystallization is important for the structural development of dairy products such as butter, ice cream, and cheese. The influence of triacylglycerol (TAG) composition on the dynamic of milk fat crystallization and the nanostructure of the formed crystals was investigated using two chemically different types of milk fat, namely buffalo and cow milk fats (BMF; CMF). The TAG composition was determined using liquid chromatography and mass spectrophotometry (LCMS), whereas differential scanning calorimetry (DSC), small- and wide-angle X-ray scattering (SAXS and WAXS), and polarized light microscopy (PLM) were used to characterize the crystallization behavior of the two milk fats. A total of 37 TAG species were identified in both BMF and CMF, but in different proportions. In particular, BMF was found to have a higher amount of low-molecular-weight TAGs in comparison to CMF. This difference in chemical composition explains the different kinetics of polymorphic transformation in the two samples. Specifically, it clarifies the delay in the nucleation of the β′-polymorph in BMF in comparison to CMF. BMF also showed a higher nucleation rate due to its higher proportion of saturated TAGs and higher melting range. Finally, this work presents a novel interpretation of the mechanism of formation of the β-polymorph (53 Å), which has recently become the subject of a vivid debate in milk fat crystallization studies
Interactions of flavonoids with lipidic mesophases
No full textAlong having various health benefits, flavonoids are increasingly being recognized as potent antioxidants and anticancer compounds. However, despite significant efforts over the last few decades to develop novel delivery systems providing higher drug bioavailability, many biofunctional aspects are still unsolved. In this chapter, we review the current knowledge on flavonoid–lipid interactions and elucidate in particular their influence on lipidic self-assembled mesophases. The interactions of flavonoids with phospholipid-based planar membranes and monoglycerides-based curved membranes are presented in detail; the main structural changes in these self-assemblies are summarized, and the correlation between membranes’ structure and function is discussed. Based on those considerations, especially the importance of membrane curvature and possible biological implications are highlighted
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
Non-equilibrium formation of the cubic Pn3m phase in a monoolein/water system
No full textTime-resolved small-angle X-ray diffraction experiments have been carried out to
investigate the transformation from the cubic gyroid Ia3d to the cubic diamond Pn3m phase.
The transition was induced by rapid addition of water to a monoolein/water system changing
the initial water concentration of 26% w/w to excess of water conditions. The transformation
proceeds in two steps: at the beginning, the two cubic mesophases have a strongly differing
lipid/water composition and are accompanied by an intermediate phase. This phase vanishes
as the ratio of cell parameters exceeds 1.50. Thereafter, the transition continues by a direct
nearly isoareal transformation of the cubic minimal surfaces. Lateral area per lipid molecule,
molecular shape and principle curvatures are about the same in this regime
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