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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
Nutrient preference of Neotropical ant assemblages along a habitat strata gradient and across trophic levels
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In different biome, we installed 10 transects as sampling units (6 × 10 = 60 transects in total) separated by at least 1 km on average. Each transect was 740 m long with 75 sampling points, each separated by 10 m. At each sampling point, we provided one of five liquid food resources into one of three habitat strata (subterranean, epigaeic and arboreal). Hence, within each transect, each resource and strata combination (5 × 3 = 15 combinations) were repeated five times in sequence along each transect. Consequently, there were five pseudoreplicates of the 15 resource/habitat strata combinations per transect (5 pseudoreplicates × 5 resource types × 3 habitat strata = 75 sampling points per transect), giving a total of 750 sampling points per biome (75 sampling points × 10 transects = 750) and 4500 sampling points across the study (750 points × 6 biomes = 4500 points in total).
We placed the food resources in 50-mL Fisher Scientific polypropylene centrifuge tubes that had a 5 cm cotton ball containing 10 ml of solutions in distilled water for each resource type. The solutions were: 1% sodium (NaCl), 20% sugar (CHO, made with sucrose), 20% amino acids (AA, made with unflavoured whey protein isolate which contains L-glutamine and other branched-chain amino acids such as leucine, isoleucine, and valine), lipids (100% extra virgin olive oil, without water), and distilled water as a control. Analogous resource solutions have successfully been used in previous studies (e.g., Fowler et al., 2014; Peters et al., 2014; Guariento et al., 2021; Lasmar et al., 2021).
The placement of the tubes was different for each habitat strata. In the subterranean strata, we placed the tubes in a plastic box (4.5 cm high, 8 cm wide and 15 cm long) with an access hole c. 1.5 cm in diameter on each side. We buried the box c. 20 cm below the soil surface. In the epigaeic strata, we placed the baited tubes horizontally on the ground. For the arboreal strata, we fixed the tubes horizontally c. 2 m above the ground on the tree trunk closest to the sampling point, using a piece of adhesive and a string to keep the tube in place. The placement of the baited tubes began at 7:00 am for each transect except in the Caatinga biome. We delayed the baiting arrangement in Caatinga until 1:00 pm because of morning rainfall that could potentially reduce ant activity. We restricted all of our sampling to take place during only sunny or partially cloudy days and never during rainfall events. We left tubes operating for three hours. After that, we closed the tubes to sample the ants inside. We considered a tube as visited when there was at least one ant individual inside.
To understand whether our baits were representatively sampling from the wider ant community we also sampled with pitfall traps. The pitfall trap data act as a proxy of ant abundance for all 60 of the baiting transects across the six biomes. By comparing ant abundance in pitfall traps and the ant foraging activity recorded by the baited tubes, we would know: (i) whether ants did not visit a bait because they did not occur in this habitat or (ii) whether baits did not attract ants due to methodological issues; (e. g. high ant abundance in pitfall traps but low ant foraging in baiting tubes, possibly indicating a problem with our baiting experiment). Thus, we started the pitfall sampling transects after the baiting experiment to avoid possible ant population depletions caused by pitfall traps (Lasmar et al. 2017). Pitfall transects were placed 20 m away in parallel from the corresponding baiting transects, totalling 60 pitfall transects across the entire study. Pitfall transects were 200 m long and had five sampling points separated by 50 m. At each sampling point, we collected ants at three habitat strata using arboreal, epigaeic and subterranean pitfall traps. Arboreal traps were installed at 1.5 m above the ground, tied in the middle of a tree trunk. Epigaeic traps were installed at the ground level and subterranean traps were buried at 20 cm under the ground. Pitfall traps were 8 cm in diameter and 12 cm in depth, and contained a 200 ml solution of water, salt (0.4%) and liquid soap (0.6%). Arboreal and epigaeic traps had a lid to cover and protect them against rain and sunlight. Subterranean traps were closed with lids and had four lateral holes of c. 1.5.cm in diameter on the sides. All pitfall traps remained in the field operating for 48 h. </p
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
Ecological Drivers and Ant Community Structure in Neotropical Biomes
No full textWe sampled ants along ten transects in each biome that were spatially separated by at least 1 km across the study (n = 60). We measured both species richness and assessed two niche dimensions - their diet and foraging habitat strata - related to five different liquid food resources at three habitat strata. Transects were 740 m long and presented 75 sampling points, separated by 10 m from each other. We placed 50 ml fisher tubes containing one of five liquids resources soaked in 5 cm cotton balls. Liquid resources were made by a solution of (distilled water/volume): 1% sodium (NaCl), 20% sugar (made with sucrose), 20% amino acids (made with unflavoured whey protein isolate) and 100% lipids (extra virgin olive oil) and 100% distilled water, as a control. Along the transects, we alternated one of the five liquid baits at one of three habitat strata (arboreal, epigaeic and subterranean, see details in Lasmar et al., 2023) totalling 4,500 baited tubes. The baited tubes placement started at 7:00 am for each transect, except in the Caatinga biome due to morning rainfall events. All baits remained operating for 3 h. Since distilled water baits were infrequently visited by ants (see Lasmar et al. 2023), we excluded such baits when categorizing the niche of ants. We, therefore, had a combination of 12 niche aspects related to the diet and foraging habits of ants across habitat strata (4 bait types × 3 habitat strata) and five replications of each of niche aspects per transect.We identified all collected ant workers into genera following Baccaro et al. (2015), and whenever possible to species and to morphospecies using the relevant literature (data in Lasmar et al., 2022) and/or matching individuals with the ant reference collection at the ‘Laboratório de Ecologia de Formigas’ of the Universidade Federal de Lavras (UFLA) and Entomological Collection Padre Jesus Santiago Moure of Universidade Federal do Paraná (UFPR). Voucher specimens are deposited in the reference collection of both collections at UFLA and UFPR.Measuring ecological driversNet primary productivity and Habitat HeterogeneityNet primary productivity (NPP) was obtained from MODIS NPP data, which represents the annual average of 2000 – 2015 years (MOD17, from NASA Earth Observation System). This is available in the repository at the University of Montana (www.ntsg.umt.edu/) at 1 km spatial resolution. The data obtained was an improved version of MOD17, which cleans cloud-contaminated pixels and considers the difference between gross primary productivity and autotrophic respiration (Zhao and Running 2010).In a parallel transect, 20 m apart from each baiting transect, we measured habitat attributes at five sampling points 50 m apart from each other to create a heterogeneity index. Details are in Appendix 1. As productivity is generally correlated with habitat heterogeneity, we checked for collinearity using the "corrplot" function from the 'corrplot' package in R (Wei and Simko, 2021). We found that more productive regions were also more heterogeneous (R = 0.65). Therefore, we solely considered net primary productivity data for the analyses as it better encompasses the area of our transects.Contemporary and past climate and stability over geological time-scalesTo accurately represent the current and past climate conditions, we used data from various sources. For the current climate, we extracted for each of our 60 transects the mean annual temperature (°C), annual precipitation (mm), temperature seasonality (standard deviation in °C of annual mean temperature) and precipitation seasonality (coefficient of variation of annual precipitation) from Worldclim2 dataset with a spatial resolution of 1 km grid cells and measures between 1970 to 2000 (Fick and Hijmans 2017). We ensured that our current climate data from Worldclim2 closely matched the weather data from the nearest climatic station measured from 1970 until the date we carried out the samplings of each biome (see Lasmar et. al., 2021a). This alignment indicated that our sampling was not conducted during extreme weather conditions and that the Worldclim2 data accurately represented both the local weather during at the time of sampling and the long-term climate trends.For past climate data, we obtained the current corresponding ecological drivers (mean annual temperature, annual precipitation, temperature seasonality and precipitation seasonality) at various time points. These time points included the last glacial maximum (21 ka; Karger et al. 2017) at 1 km of resolution, the last interglacial in the Pleistocene (c. 130 ka; Otto-Bliesner et al., 2006), the early Pleistocene (c. 787 ka. Brown et al., 2018), and the Pliocene (c. 3.3 Ma; Dolan et al., 2015) - all last three at 5 km of resolution. All past climate data were downloaded on PaleoClim.org (Brown et al., 2018). To assess the collinearity between current and past climate variables, we employed the corrplot function from the ‘corrplot’ package in R (Wei and Simko, 2021). All current climate variable representations were highly correlated with their past correspondents (i.e., r > 0.80; Appendix 1, Fig. S2-S5), indicating that at least in a range of c. 3.3 Ma, geographical variation in temperature, precipitation and their seasonality of our sampled regions remained almost the same. Thus, we solely considered current climate data for the analyses.For each transect, we also obtained the climatic stability over geological time-scales data from Herrando-Moraira et al. (2022) study, with 5 km of resolution and corrected for the collinearity of climatic variables and the sea level variation across history. The climatic stability index was created by extracting the standard deviation (SD) as an estimate of the amount of variation of 14 climatic variables available in PaleoClim.org across 12 time periods, from Pliocene (3.3 Ma) to the present. Then, it was summed the SD values of all 14 variables and this value was normalized from 0 to 1 (i.e., 0 completely stable; 1 most unstable).</p
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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