1,721,017 research outputs found
Russell Duncan ? Anna Mohagen Family History
Get PDFPhotocopy of handwritten genealogy of the Duncan and Mohagen families with autobiographies of Russell (born William Russell Duncan) and Anna Mohagen Duncan
The measurement of dimethylsulphide precursors in marine and terrestrial flora
No full textFlow injection apparatus was designed based on the use of selective reaction chemistry and sulphur specific flame photometric detection. The performance of two reaction systems was assessed using seven synthesised dimethylsulphonium compounds (dimethylsulphonio propionate (DMSP), dimethylsulphonio-2-methyl propionate, S-methyl methionine (SMM), dimethylsulphonio acetate, dimethylsulphonio butanoate, dimethylsulphonio pentanoate, dimethylsulphonio choline). Base hydrolysis was found to be selective towards dimethylsulphonio propionate, whilst sodium tetrahydridoborate (borohydride) gave a virtually equal response to all seven compounds.Two HPLC instruments were developed based on the reaction chemistries and detection systems employed in the flow injection apparatus. The chromatographic separation of the seven synthesized DMS precursor compounds on both anion- and cation-exchange media was evaluated for the identification of DMS precursors. This apparatus provides the basis for the first reliable identification of DMS precursor compounds at trace levels. The 3σ detection limit employing base hydrolysis is 1.29 x 10-7 mol(DMSP) dm-3 (200 μl injected), corresponding to an absolute injected mass of 3.5 ng (DMSP).Macroalgae, microalgae, flowering plants, barley and cyanobacteria were analysed for DMS precursor compounds. DMSP was identified as being present in a wide range of flora at concentrations of between 2.9 μmol kg-1 fresh weight (FW) and 29.4 mmol kg-1 FW. The instability of DMSP towards enzymatic and chemical breakdown requires particular attention to be given to sample collection and storage. An extraction method was developed involving 2% HC1 to deactivate DMSP- consuming enzymes and to slow chemical hydrolysis. The results constitute the first direct sulphur specific measurements of DMSP at trace levels. In macroalgae, levels ranged from 0.0010 to 29.4 mmol(DMSP) kg-1 FW. For plankton levels between 0.82 to 158 μmol(DMSP) mg(chl'a')-1 were recorded. SMM was found in cabbage and parsley (74.32±7.00 and 16.11 ± 0.78 μmol kg-1 FW respectively) and these results constitute the first direct measurements of SMM at trace levels.</p
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
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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