1,721,039 research outputs found
Determination of free L- and D-alanine in hydrolysed protein fertilisers by capillary electrophoresis
No full textThe objective of this study was to determine the degree of racemisation of hydrolysed protein fertilisers (HPFs) using an inexpensive and easy to handle analytical method for qualitative control of the products. Using a polyacrylamide coated capillary and a run buffer containing 0.1 M Tris-borate+2.5 mM EDTA-Na2+0.1% sodium dodecylsulfate+10 mM β-cyclodextrin a quantitative separation of D- and L-alanine (Ala) was made from an not treated HPF sample derivatised with dansyl chlorine by capillary electrophoresis. The D-Ala:[D-Ala+L-Ala] ratio, called degree of racemisation (RD), was calculated. The analysis of ten commercial HPFs has shown that more than 60% of HPFs have an RD ≥40%, while only one product has shown an RD <5%. These results showed that most of the HPFs on the market are obtained with strong hydrolytic processes and high contents of D-amino acids are probably less effective as plant nutrients or even potentially dangerous to plants. © 2002 Elsevier Science B.V. All rights reserved
Identification of organic matter from peat, leonardite and lignite fertilisers using humification parameters and electrofocusing
No full textThe organic matter extracted from peats (P), leonardites (Le) and lignites (Li) was characterised by humification parameters and electrofocusing (EF). The degree of humification and the humification index might be used to distinguish P from Le and Li, but not Le from Li because they showed overlapped values, while the humification rate could be used only for the identification of Le and EF profiles of P, Le and Li fertilisers revealed different band patterns: P samples did not show bands in the region with isoelectric point, pI>4.4; Le samples showed very intense bands in the region with pI>4.4; Li samples showed a very different band pattern with poorly resolved bands in the region with pI>3.8. P, Le and Li samples can be distinguished by combining humification parameters and EF. © 2002 Elsevier Science Ltd. All rights reserved
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
Effects of the rate of protein hydrolysis and spray concentration on growth of potted kiwifruit (Actinidia deliciosa) plants
No full textProducts obtained by hydrolysis of proteins have been recently used as foliar fertilisers in several fruit growing areas. In this study we have assessed the effects of the rate of protein hydrolysis and that of the N concentration in the sprayed solution on the vegetative growth of potted kiwifruit plants. Protein hydrolysates were obtained by enzymatic hydrolysis of "peptone from gelatine". The four fractions obtained (with nominal molecular weights of < 1, 1-3, 3-10 and > 10 kDa), the unhydrolysed peptone and the peptone hydrolysed but not subjected to separation were sprayed at three different concentrations (240, 400 and 800 mg N L-1). Each product was sprayed five times at ten day intervals. Control, untreated, plants and plants treated with urea were present as well. After one month from the first treatment application, the fractions with lowest nominal molecular weights stimulated, especially at lowers rates, shoot growth. The application at highest rate of the fractions with nominal molecular weight 3-10 kDa and > 10 kDa induced shoot growth and biomass increments higher than those caused by urea sprays. The hydrolysed-unfractionated peptone, regardless the rate applied, adversely affected vegetative growth and canopy biomass after two months from the beginning of treatment application, while the unhydrolysed peptone stimulated in the short term vegetative growth when applied at highest rate and performed better than urea. Root growth and biomass linearly increased with the rate of organic N when applied with fraction of 1-3 kDa and > 10 kDa. Data of nitrogen concentrations and content in leaves suggest that vegetative growth effects of the products evaluated are not only due to increase of N nutrition
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
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