1,354,449 research outputs found
Structure of acid casein gels : a study of gels formed after acidification in the cold
No full textThe structure of acid casein gels was studied by rheology, permeametry, electron microscopy and pulse NMR. Gels were mainly formed by heating at rest of casein solutions acidified in the cold (0- 2 °C). The structure of such gels involves both the spatial distribution of the structural elements and the interaction forces between them. An acid casein gel has an irregular particulate structure. Gelation results from the aggregation of casein particles, which themselves have a complex internal structure due to the association of numerous different casein molecules. Dense areas of coagulated particles are separated by large pores. Gelation at pH=4.6 appears to be subject to an activation Helmholtz energy, which is largely due to the stabilizing effect of the glycomacropeptide part of K-casein. At ageing temperatures above 283 K, the dynamic moduli G' and G'' linearly increase with the logarithm of time. Their absolute values primarily depend on the heterogeneity of the network. The moduli decrease with increasing time scale of measurement. From the effect of variation of experimental conditions (pH, ageing and measuring temperatures, ionic strength and ionic composition) it may be concluded that electrostatic interactions and hydrophobic bonding are involved in keeping the network together. Moreover, Van der Waals attraction, steric interactions and possibly hydrogen bonds may play a part. Differences in the internal structure of the casein particles appear to be paramount in determining differences in the number and character of the interparticle bonds; this was in agreement with results on the spin-spin relaxation time of water protons. Addition of rennet enables gel formation in a much broader range of temperature and pH; the character of the gels changes considerably around pH=5.2
Type I PIPkinases Interact with and Are Regulated by the Retinoblastoma Susceptibility Gene Product—pRB
No full textInositide signaling at the plasma membrane has been implicated in the regulation of numerous cellular processes including cytoskeletal dynamics, vesicle trafficking [1], and gene transcription [2]. Studies have also shown that a distinct inositide pathway exists in nuclei [3], where it may regulate nuclear processes such as mRNA export [4], cell cycle progression [5–8], gene transcription [9], and DNA repair [10]. We previously demonstrated that nuclear PtdIns(4,5)P2 synthesis is stimulated during progression from G1 through S phase [11], although mechanistic details of how cell cycle progression impinges on the regulation of nuclear inositides is unknown. In this study, we demonstrate that pRB, which regulates progression of cells from G1 through S phase [12] interacts both in vitro and in vivo with Type I PIPkinases, the enzymes responsible for nuclear PtdIns(4,5)P2 synthesis. Moreover, this interaction stimulates the activity of Type Iα PIPkinase in an in vitro assay. Using murine erythroleukamia (MEL) cells expressing a temperature-sensitive mutant of large T antigen (LTA), we demonstrate changes in vivo in nuclear PtdIns(4,5)P2 levels that are consistent with the ability of LTA to disrupt pRB/Type I interactions. This study, for the first time, provides a potential mechanism for how cell cycle progression could regulate the levels of nuclear inositides
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
Can(not) take my eyes off it: Attention bias for food in overweight participants
Get PDFObjective: The aim of the current study was to investigate attention biases for food cues, craving and overeating in overweight and healthy weight participants. Specifically, it was tested whether attention allocation processes towards high-fat foods differ between overweight and normal weight individuals and whether selective attention biases for food cues are related to craving and food intake. Design: Eye movements were recorded as a direct index of attention allocation in a sample of 22 overweight/obese and 29 healthy weight female students during a visual probe task with food pictures. In addition, self reported craving and actual food intake during a bogus “taste-test” were assessed. Main outcome measures: Attention biases towards food cues in initial gaze direction, first fixation durations and total dwell time as indexed by recordings of eye-movements. Results: Overweight participants showed an approach-avoidance pattern of attention allocation towards high-fat food: Overweight participants directed their first gaze more often towards food pictures than healthy weight individuals, but subsequently showed reduced maintenance of attention on these pictures. For overweight participants, craving was related to initial orientation towards food. Moreover, overweight participants consumed significantly more snack food than healthy weight participants. Conclusion: Results emphasize the importance of identifying different attention bias components in overweight individuals with regard to craving and subsequent overeating
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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
Author, publisher and bookseller : a tripartite synergy in Nigerian book industry
Get PDFThis work is about the roles of Author, Publisher and Bookseller in Book development in
Nigeria. The paper started by delving into the history of Book Publishing in Nigeria after
which it proceeded by defining who an author, a publisher, and a bookseller is and
expatiated on the indispensable roles of these key actors in Nigerian Book Industry and in
the emerging Information Society. Furthermore, the various constraints to book
development were identified while the paper advised on how the Book Industry can be
further promoted in Nigeria. However, the paper concluded and made recommendations
on how the Book sector can help in enhancing scholarship in the country
The Thursday Murder Club: Launching a megabrand author - a publishing case study
Get PDFIn 2020, the Christmas book charts in the UK made headlines: Barack Obama’s eagerly awaited autobiography, The Promised Land, was beaten to the top spot by The Thursday Murder Club by Richard Osman, a debut cosy crime novel set in a retirement village. Not only did Osman’s book beat the former US president’s expected bestseller, it also broke records, becoming the fastest-selling debut crime novel of all time. Although Osman has a certain level of fame in the UK from his TV appearances on shows such as Pointless, his celebrity status does not entirely explain the novel’s huge sales. This article tracks the acquisition, publication, and promotion journey of The Thursday Murder Club in order to understand the industry and cultural context of its success and to interrogate the role of celebrity in the creation of author brands. The findings suggest that the unexpected scale of the success of the book owed to a number of factors, including in-depth editing by the novel’s agent, editor, and author to tighten up the plot, an extensive and strategic promotional campaign, the pandemic (which drove interest in the book’s genre and themes), and the quality of the writing. We find that the book’s success was accentuated by Osman’s celebrity status rather than being entirely reliant on it. This research adds to the growing scholarship on celebrity authorship by means of an in-depth case study and provides insight into the processes behind publishing a ‘celebrity’ book and launching a megabrand author
CO 2 -enhanced oil recovery and CO 2 capture and storage: An environmental economic trade-off analysis
No full textCO 2 enhanced oil recovery can play a significant role in stimulating carbon capture and storage because of additional oil revenues generated. However, it also leads to additional greenhouse gas emissions. We estimate the global warming potential of different CO 2 capture scenarios with and without enhanced oil recovery. During a 10 year period in which oil and electricity are produced without CO 2 being captured, the global warming potential is 11 MtCO 2 equivalents. We show that if CO 2 is captured and used for 15 years of enhanced oil recovery, the global warming potential decreases to 3.4 MtCO 2 equivalents. This level is 100% higher compared to the scenario in which the captured CO 2 would be stored in an offshore aquifer instead. If the capture of CO 2 is stopped when the oil reservoir is depleted, the global warming potential resulting from 10 years electricity production is 6 MtCO 2 equivalents. However, if CO 2 is stored in the depleted reservoir, the global warming potential is six times lower during that period. Electricity production and oil refining are the main contributors to the global warming potential. The net present value analysis indicates that for CO 2 prices lower than or equal to 15 €/t and oil prices greater than or equal to 115 €/t, it is most profitable to capture CO 2 for enhanced oil recovery only. Because of the low CO 2 price considered, large incomes from oil production are required to stimulate CO 2 capture. The environmental economic trade-off analysis shows that if CO 2 -enhanced oil recovery is followed by CO 2 capture and storage, costs increase, but the net present value remains positive and the global warming potential is reduced. Authorities could use these outcomes to support the development of economic mechanisms for shared investments in CO 2 capture installations and to mandate both oil producer and large CO 2 emitting firms to store CO 2 in depleted oil fields
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