1,720,960 research outputs found
Relevance of different apolipoprotein content in binding of homocysteine to plasma lipoproteins
No full textBackground and Aims: In plasma the atherogenic thiol homocysteine (Hcy) circulates either free or bound to proteins (Pb-Hcy). The present study sets out to evaluate the lipoprotein-Hcy (LP-Hcy) binding in vivo and the possible influence of different apolipoprotein content in this binding, being lipoprotein oxidation a possible mechanism of Hcy-induced damage. Methods and Results: In 34 healthy subjects we assayed fasting plasma lipoprotein and correspondent apolipoprotein (apo A-I, apo A-II, apo C-II, apo C-III, apo B, apo(a) and apo E content, and Hcy bound to different plasma protein fractions; moreover ten subjects underwent an oral methionine load in order to evaluate possible dynamic modifications of Pb-Hcy and LP-Hcy after induction of hyperhomocysteinemia. Pb-Hcy (mean values 9.22+/-1.7 mumol/L) represented about 78% of total plasma Hcy (mean values 11.8+/-1.8 mumol/L). Pb-Hcy distribution between the different fractions was as follows (mumol/L): VLDL = 0.25+/-0.08 (2.7%); LDL = 0.88+/-0.22 (9.5%);HDL = 1.40+/-0.36 (15.2%);fractions with density greater than 1.21 g/mL (Lipoprotein-Free Protein Fraction, LPDS) = 6.7+/-1.2 (72.6%). Hcy/protein ratios (nmol/mg of protein) in each protein fraction were: VLDL = 0.32+/-0.19, LDL = 0.43+/-0.37, HDL = 0.26+/-0.18, LPDS < 0.1, thus suggesting a higher binding capacity for Hcy by VLDL and LDL. These data were confirmed by the higher increase in Hcy content in LDL and VLDL (76 and 90%, respectively vs 36% and 3.1% for HDL and LPDS fractions) after hyperhomocysteinemia. Lp-Hcy binding significantly correlated with the apo B content of VLDL and LDL and Apo A-I content of HDL. Conclusions: An important fraction of plasma Hcy circulates bound to LP (about 27% of Pb-Hcy); VLDL and LDL show the highest binding capacity for Hcy, probably due to their content in Apo B, a possible high capacity binding site for Hcy. (C)2003, Medikal Press
Riciclo di amianto inertizzato termicamente in impasti da grès porcellanato.
No full textNella presente ricerca si è valutata la possibilità di riciclare amianto inertizzato termicamente con torcia al plasma, in impasti da grès porcellanato. Il materiale inertizzato, denominato INERTAM, è costituito per circa 50% da una fase amorfa. Il restante 50% è costituito da fasi cristalline fra le quali prevale la gehlenite-akermanite (ca. 36% del totale). Considerando il carattere refrattario dell'INERTAM, si è ritenuto opportuno sostituirlo ai materiali, quali le sabbie, che negli impasti ceramici svolgono una funzione smagrante e strutturale. Partendo da un impasto da grès porcellanato commerciale, scelto come riferimento, è stato preparato un nuovo impasto, sostituendo il 2.5% di sabbia feldspatica con l'1%di INERTAM.Il nuovo impasto ha messo in evidenza caratteristiche migliori rispetto al materiale standard, presentando a 1220°C, valori di assorbimento d'acqua inferiori, 0,82%, e un ritiro lineare di 7,9%. Le analisi al microscopio elettronico a scansione (SEM), dei provini sinterizzati, hanno evidenziato una microstruttura più omogenea e meno porosa rispetto a quella dell'impasto standard
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
Relevance of different apolipoprtein content in homocysteine binding to plasma lipoproteins
No full textBackground and aims: In plasma, homocysteine (Hcy) circulates free or bound to proteins (Pb-Hcy). Our study sets out to assess the lipoprotein-Hcy (LP-Hcy) binding in vivo and the possible influence of different apolipoprotein content in this binding. Methods: In 34 healthy subjects fasting plasma lipoprotein (Sequential ultra-centrifugation) and correspondent apolipoprotein (apo A-I, apo A-II, apo C-II, apo C-III, apo B, apo(a) and apo E) content (Immunoturbidimetric assay), and Hcy (HPLC) bound to different plasma protein fractions were assessed; ten subjects underwent a methionine oral load in order to evaluate Pb-Hcy and LP-Hcy modifications after induction of hyperhomocysteinemia (HHcy). Results: Pb-Hcy (mean values 9.22±1.7 mol/L) resulted 78% of total plasma Hcy (mean values 11.8±1.8 mol/L). Pb-Hcy distribution between the different fractions was as follows (mol/L): VLDL= 0.25 ± 0.08 (2.7 %); LDL= 0.88 ± 0.22 (9.5 %); HDL =1.40 ± 0.36 (15.2 %), Lipoprotein-Free Protein Fraction (LPDS) = 6.7 ± 1.2 (72.6 %). Hcy/protein ratios (mol / g of protein) of each protein fraction were: VLDL= 0.32 ± 0.19, LDL= 0.43 ± 0.37, HDL= 0.26 ± 0.18, LPDS < 0.1, this suggesting a higher binding capacity for Hcy of VLDL and LDL. This data was confirmed by the higher increase in Hcy content in LDL and VLDL (+76 and +90%, respectively vs. +36% and +3.1 % for HDL and LPDS fractions) after HHcy. Lp-Hcy binding significantly correlated with the apo B content of VLDL and LDL and Apo A-I content of HDL. Conclusions: An important fraction of Hcy circulates bound to LP (about 27% of Pb-Hcy); VLDL and LDL show the highest binding capacity for Hcy; this may be due to content in Apo B, a possible high capacity binding site for Hcy (great availability of free cysteine and lysine residuals)
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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