1,720,965 research outputs found
Measurement of Purine Derivatives and Creatinine in urine by HPLC. In Estimation of Microbial Protein Supply in Ruminants Using Urinary Purine Derivatives
No full textTwo HPLC methods to measure the purine derivativcs (PD), including allantoin, uric acid, hypoxanthine and xanthine) and creatinine content in urine are described. PD separation and quantification were achieved using two Spherisorb ODS 2 reversed phase columns connected in series (4.6 x 250 mm) and a Spherisorb ODS 2 Waters pre-column and a Perkin Elmer pump with an autosampler. The mobile phase was NH4H2PO4; NH4H2PO4: acetonitrile (80:20), which was used at a flow rate of 0.8 ml/min and the detection wavelength was at 190 nm. The average recoveries of standard compounds added to urine samples were satisfactory (92-106%) and the low detection limits (0.7-3.4 μM) permitted the precise determination of these compounds in urine.
Separation and quantification of crcatinine was achieved using one Spherisorb ODS 2 reversed phase column (4.6 X 250 mm) and one Spherisorb ODS 2 Waters pre-column and a Perkin Elmer pump with an auto sampler. The mobile phase was NH4H2PO4; NH4H2PO4;-acetonitrile (80:20), used at a how rate of 1.00 m1/min and the detection was at 190 nm. The mean recovery (3 measurements) of standard solution added to urine samples was 101%; detection limit was 7.9 μM
Single and Repeated Applications of Cerium Oxide Nanoparticles Differently Affect the Growth and Biomass Accumulation of Silene flos-cuculi L. (Caryophyllaceae)
Full text linkCerium oxide nanoparticles (nCeO2) have a wide variety of applications in industry. Models demonstrated that nCeO2 can reach environmental compartments. Studies regarding the relationships between plants and nCeO2 considered only crop species, whereas a relevant knowledge gap exists regarding wild plant species. Specimens of Silene flos-cuculi (Caryophyllaceae) were grown in
greenhouse conditions in a substrate amended with a single dose (D1) and two and three doses (D2 and D3) of 20 mg kg1 and 200 mg kg1 nCeO2 suspensions, respectively. sp-ICP-MS and ICP-MS data demonstrated that nCeO2 was taken up by plant roots and translocated towards aerial plant fractions. Biometric variables showed that plants responded negatively to the treatments with a shortage in biomass of roots and stems. Although not at relevant concentrations, Ce was accumulated mainly in roots and plant leaves
Apparent Metabolisability of Diets Containing Concentrate, Zostera Noltii or Taraxacum Officinalis in Anas Penelope
Full text linkFour metabolisability trials on captive Wigeons were conducted comparing a complete pelleted diet with others
where Taraxacum officinalis and Zostera noltii were added. The daily dry matter (DM) intake of Wigeons varied
from 54.4 to 65.5 g/day and the amount of nutrients received from the four diets was similar. The nitrogen (N)
content of droppings statistically diminished when Wigeons were fed diets containing Zostera noltii. Correlation
among cell wall components (CWC) of droppings and that of intakes was always highly significant and positive. The
DM metabolisability of the four diets was 42-51 %. The crude protein (CP) metabolisability varied significantly from
21 % for the diet with Taraxacum to 39 % for that with the Zostera collected in June. The metabolizabilities of CWC
also differed significantly among diets. The apparent metabolizabilities of ash with the Zostera diets were
significantly higher when compared to those of two other diets
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
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
- …
