1,721,007 research outputs found
Ride to cell wall: Arabidopsis XTH11, XTH29 and XTH33 exhibit different secretion pathways and responses to heat and drought stress
No full textThe xyloglucan endotransglucosylase/hydrolases (XTHs) are enzymes involved in cell wall assembly and growth regulation, cleaving and re-joining hemicellulose chains in the xyloglucan–cellulose network. Here, in a homologous system, we compare the secretion patterns of XTH11, XTH33 and XTH29, three members of the Arabidopsis thaliana XTH family, selected for the presence (XTH11 and XTH33) or absence (XTH29) of a signal peptide, and the presence of a transmembrane domain (XTH33). We show that XTH11 and XTH33 reached, respectively, the cell wall and plasma membrane through a conventional protein secretion (CPS) pathway, whereas XTH29 moves towards the apoplast following an unconventional protein secretion (UPS) mediated by exocyst-positive organelles (EXPOs). All XTHs share a common C-terminal functional domain (XET-C) that, for XTH29 and a restricted number of other XTHs (27, 28 and 30), continues with an extraterminal region (ETR) of 45 amino acids. We suggest that this region is necessary for the correct cell wall targeting of XTH29, as the ETR-truncated protein never reaches its final destination and is not recruited by EXPOs. Furthermore, quantitative real-time polymerase chain reaction analyses performed on 4-week-old Arabidopsis seedlings exposed to drought and heat stress suggest a different involvement of the three XTHs in cell wall remodeling under abiotic stress, evidencing stress-, organ- and time-dependent variations in the expression levels. Significantly, XTH29, codifying the only XTH that follows a UPS pathway, is highly upregulated with respect to XTH11 and XTH33, which code for CPS-secreted proteins
LYCOPENE DIET SUPPLEMENTATION DECREASES OXYSTEROLS AS IMPROVES ANEMIC STATUS DESPITE NO EFFECTS ON INFLAMMATION IN AGING WITH CKD
No full text
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
Bioactive Compounds and Antioxidant Activities in Different Fractions of Mango Fruits (Mangifera indica L., Cultivar Tommy Atkins and Keitt)
No full textThis study aims to describe and compare the distribution of bioactive compounds, the fatty acids profiles, and the TEAC hydrophilic and lipophilic antioxidant activities in different fruit fractions (pulp, peel, and kernel) of two mango cultivars (Tommy Atkins and Keitt). All fractions are sources of health‐promoting bioactive compounds. Regardless of cultivars, pulp had the highest content of phytosterols (~150 mg/100 g dw), peels ranked first for pentaciclic triterpenes (from 14.2 to 17.7 mg/100 g dw), tocopherols, carotenoids, and chlorophylls, and kernels for phenolic compounds (from 421.6 to 1464.8 mg/100 g dw), flavonoids, condensed tannins, as well as hydrophilic and lipophilic antioxidant activities. Differences between the two cultivars were evidenced for ascorbic acid, which showed the highest levels in the peels and kernels of Keitt and Tommy Atkins fruits, respectively. Similarly, the concentration of dehydroascorbic acid was higher in the pulp of Tommy Atkins than Keitt. The highest percentage of saturated fatty acids was observed in pulp (~42%) and kernels (~50%), monounsaturated fatty acids in kernels (up to 41%), and polyunsaturated fatty acids in peels (up to 52%). Our results add information to the current knowledge on nutraceuticals’ distribution in different fractions of mango fruit, supporting its consumption as a healthy fruit and suggesting the great potential value of peels and kernels as sources of novel ingredients. Indeed, mango by‐products generated during agronomic‐to‐industrial processing not only causes a significant environmental impact, but economic losses too. In this scenario, boosting research on conventional recovery methods offers eco‐friendly solutions. However, green, novel biorefinery technologies may offer eco‐friendly and profitable solutions, allowing the recovery of several more profitable by‐products, sustaining their continuous growth since many bioactive compounds can be recovered from mango by‐products that are potentially useful in the design of innovative nutraceutical, cosmeceutical, and pharmaceutical formulations
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
- …
