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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
Lepidosperma undetermined
No full text<i>2.2. Lepidosperma sp. Flinders Chase resinous exudates foraged by honey bees to produce propolis</i> <p> In the north west coastal De Mole River area of Kangaroo Island honey bees were observed collecting resin from <i>Lepidosperma</i> sp. Flinders Chase. Resin samples were collected from plants (Fig. 2S) and bee legs and, also, freshly deposited propolis was collected from nearby beehives. 1 H NMR spectral analyses of ethanol extracts of the resin samples and S 2 type propolis showed that they closely matched in constituent profile indicating that the plant was the botanical source of the resin collected by the bees to produce the propolis sample from the hive (Fig. 3).</p> <p> TLC analytical (Fig. 1S) and 1 H NMR spectral profiles of 73 <i>Lepidosperma</i> sp. Flinders Chase resin samples collected over KI showed two distinct patterns for the distribution of quantities of the compounds <b>1</b> to <b>3</b>, and <b>6</b> and <b>7.</b> For 60 samples one pattern was observed that showed variations for <b>1</b>, <b>3,</b> and <b>6</b> from rich to depleted and that <b>7</b> was always a minor constituent over all samples. These plant resin samples came from plants widely distributed over KI and isolated yields for compounds <b>1</b>, <b>3</b>, <b>6</b> and <b>7</b> were 4%, 12%, 10% and 0.5% respectively.</p> <p> a Measured in CDCl relative to TMS.</p> <p> 3 b Measured in CD OD relative to TMS.</p> <p> 3</p> <p> For 13 plant samples collected from Cape Borda and Stunsail Boom exposed coastal locations another pattern was observed that showed only compounds <b>2</b> and <b>3</b> as major constituents with isolated yields of 18% and 16% respectively.</p> <p> Compound <b>1</b> is the methyl ester of 3-phenyl-2-(<i>E</i> -cinnamoyloxy) propanoic acid. The free acid form, commonly known as <i>O</i> -(<i>trans</i> -cinnamoyl)-L- <i>β</i> -phenyllactic acid, has been much studied is the past as a substrate for the zinc-containing metalloenzyme carboxypeptidase A (Awazu et al., 1967). Recent interest is focused on <i>β</i> -phenyllactic acid which exhibits broad spectrum antimicrobial activity and is also of current interest as a food additive as an alternative to antibiotics for food preservation (Chaudhari and Gokhale, 2016). <i>β</i> -Phenyllactic acid has been found in honey at levels of 100–800 mg /kg.</p> <p> 3-(8- <i>E</i> -Methoxy-8-oxo-3,7-dimethyloct-2-enyl)-4-hydroxy- <i>E</i> -cinnamic acid (<b>2</b>) and 3-(<i>E</i> -6,7-dihydroxy-3,7-dimethyloct-2-enyl)-4-hydroxy- <i>E</i> -cinnamic acid (<b>3</b>) appear to be metabolites of 3-geranyl-4- hydroxy- <i>E</i> -cinnamic acid where, from position 6 of the geranyl group, the group is oxidized. Both of these metabolic modifications are uncommon and no similar structures were found. By contrast, metabolites of 3-geranyl-4-hydroxycinnamic acid from <i>Chrysothamnus pulchellus</i> (Asteraceae) were hydroxylated at the allylic 4-positions on the geranyl group (Jakupovic et al., 1990).</p> <p> Known stilbene, 2-prenyl-3,5-dihydroxy- <i>E</i> -stilbene (<b>6</b>) was previously isolated from <i>Glycyrrhiza flavescens</i> (Fabaceae) (Kusano et al., 2002) and, also, the known stilbene 2-prenyl-3-methoxy-5-hydroxy- <i>E</i> -stilbene (<b>7</b>), was previously isolated from <i>Lonchocarpus violaceus</i> (Fabaceae) (Delle Monache et al., 1977) and <i>Cajanus cajan</i> (Fabaceae) (He et al., 2019) (Fig. 4).</p>Published as part of <i>King, Douglas I., Hamid, Kaiser, Tran, Van H., Duke, Rujee K. & Duke, Colin C., 2021, Kangaroo Island propolis types originating from two Lepidosperma species and Dodonaea humilis, pp. 1-11 in Phytochemistry (112800) (112800) 188</i> on pages 4-5, DOI: 10.1016/j.phytochem.2021.112800, <a href="http://zenodo.org/record/8259223">http://zenodo.org/record/8259223</a>
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
Lepidosperma viscidum R. Br.
No full text2.3. F type propolis and its botanical source from L. viscidum A plant source foraged by honey bees to produce propolis on Kangaroo Island was found to be the resinous exudate of Lepidosperma sp. Montebello (Duke et al., 2017). The resinous exudates from other species of Lepidosperma genus collected on KI and south-east South Australia were compared by TLC and 1 H NMR analysis with propolis samples. A close match was found for both TLC (Supplementary data, Fig. 3S) and 1 H NMR spectra profiles (Fig. 5) between resin from L. viscidum (Fig. 4S) and propolis samples rich in 1 H NMR signals characteristic of flavanones, designated as F type propolis. F type propolis is relatively uncommon on KI (18 out of 2602 samples) and relatively common in south-east South Australia (4 out of 11 samples). This frequency of appearance is consistent with the uncommon occurrence of L. viscidum on KI and its common occurrence in the areas in South Australia from where F-type propolis samples were collected. L. viscidum resinous leaf and leaf base ethanol extract from Seal Bay, KI, was fractionated by normal-phase short column vacuum chromatography and fractions of sufficient purity were characterised by 1 H and 13 C NMR spectra and mass spectrometry resulting in the identification of five compounds 4, 5, 8, 9 and 10. Chemistry of L. viscidum resin is markedly different from that previously observed in another propolis resin sourced from Lepidosperma genus on Kangaroo Island (Duke et al., 2017; Abu-Mellal et al., 2012). This propolis type has resin sourced from Lepidosperma sp. Montebello, with chemistry extensively investigated (Duke et al., 2017; Abu-Mellal et al., 2012). The compounds isolated from resins of that species are predominantly C- and O-prenylated hydroxystilbenes or derivatives thereof, many with piceatannol as base structure. By comparison, L. viscidum resin appears to be predominantly 6- or 8-methyl or dimethyl polyhydroxyflavanones 8, 9 and 10 (Fig. 6); 1 H NMR spectra of less pure fractions also suggests the presence of some O-methylated flavanones. Notably, prenylation appears to be less common in L. viscidum resin compounds, with the exception of the two dihydrochalcones, 4 and 5, isolated. Compounds similar to 4 and 5 without the 4-hydroxyprenyl substituent, 4,2 ′,4 ′ -trihydroxydihydrochalcone (davidigenin) (Jensen et al., 1977) and 4,2 ′ -dihydroxy-4 ′ -methoxydihydrochalcone (Kostrzewa-Susłow and Janeczko, 2012) have 1 H and 13 C NMR spectral results that show good partial concordance with 4 and 5. The most similar structure to 5 reported was 3 ′ -prenyl-4,2 ′ -dihydroxy-4 ′ -methoxydihydrochalcone (Awouafack et al., 2010). The stereoisomer identified in 4 and 5 was the E configuration. This configuration is reported to be predominant in terminally-hydroxylated prenyl groups in natural products (Erasto et al., 2004; Nguyen et al., 2012). Compounds 4 and 5 are previously undescribed: a number of 3 ′ -prenyl hydroxydihydrochalcones have been reported from natural sources but no 5 ′ -prenylated structures to date. These 3 ′ -prenyl hydroxydihydrochalcones have been isolated from genera Angelica (Apiaceae) (Luo et al., 2012a), Artocarpus (Moraceae) (Jamil et al., 2008), Bacopa (Plantaginaceae) (Suresh et al., 2010), Broussonetia (Moraceae) (Luo et al., 2012b), Eriosema (Fabaceae) (Awouafack et al., 2008, 2010) and Lonchocarpus (Fabaceae) (Borges-Arg´aez et al., 2009), none of these genera being closely related to the Cyperaceae. Limited information on biological activity of these compounds exists, but one is a reported strong free radical scavenger by the DPPH assay (Jamil et al., 2008) and another has been observed to inhibit aromatase (Luo et al., 2012b). The molecular weight of compounds identified as 5,7,4 ′ -trihydroxy- 6,8-dimethylflavanone (farrerol) (8), 5,7,3 ′,5 ′ -tetrahydroxy-6,8-dimethylflavanone (9) and 5,7,3 ′,5 ′ -tetrahydroxy-6-methylflavanone (10) was determined by mass spectrometry. Close matches with literature 13 C NMR and 1 H NMR spectra enabled identification of the structures of these known compounds: farrelol (8) (Lai et al., 2016); 9 (Lou et al., 2015); 10 (Yi et al., 2002; Zhang et al., 2018). Farrerol (8) has a long history in the literature and has been isolated from plants from a widespread number of genera (Lai et al., 2016). Compound 9 has previously been isolated from Rhododendron dauricum (Ericaceae) (Wang et al., 2015) as per farrerol, and 10 from the conifer Pseudotsuga sinensis (Pinaceae) (Yi et al., 2002; Zhang et al., 2018). Neither species belong to families closely related to the Cyperaceae. No reports of biological activity for these compounds were found (Wang et al., 2015; Yi et al., 2002; Zhang et al., 2018). F type propolis and its resin source L. viscidum are a promising source of a diverse range of flavanones of potentially useful biological activity, and of farrerol, a compound of intense pharmaceutical interest (Dai et al., 2016) and long-term traditional use (Chen et al., 2009).Published as part of King, Douglas I., Hamid, Kaiser, Tran, Van H., Duke, Rujee K. & Duke, Colin C., 2021, Kangaroo Island propolis types originating from two Lepidosperma species and Dodonaea humilis, pp. 1-11 in Phytochemistry (112800) (112800) 188 on page 6, DOI: 10.1016/j.phytochem.2021.112800, http://zenodo.org/record/825922
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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