1,720,959 research outputs found
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
Stock enhancement of local populations of blacklip abalone (Haliotis rubra Leach) in New South Wales, Australia
Full text linkThis thesis examines the release and long-term (>2 years) survival and growth of hatchery-reared larval and juvenile blacklip abalone (Haliotis rubra Leach), on natural coastal reefs in New South Wales (NSW), Australia. Abalone are demersal, relatively sedentary, marine molluscs, that support important commercial, recreational and indigenous fisheries in numerous locations around the world. This thesis was developed in response to substantial depletions of local populations of H. rubra along >250 km of the NSW coast and the ineffectiveness of traditional fisheries management strategies to arrest these declines. These failures stem from demographic processes, common to haliotids, that limit their ability to re-establish populations that have been subject to substantial decline. A series of laboratory and field experiments were designed and conducted to examine a range of factors, and their interactions, that can have substantial affects on the success of releasing hatchery-reared H. rubra to natural reefs. The principal finding was that successful stock enhancement of local populations can be achieved, and the greatest value of a stock enhancement strategy is likely to be gained where the primary management objective is rebuilding depleted natural populations. Methodology, baseline targets and other recommendations are provided that would aid implementation of a stock enhancement management strategy to complement current traditional fisheries management approaches. The objectives of the research in this thesis were to: 1) investigate factors affecting the settlement, metamorphosis and early growth of H. rubra larvae; 2) batch-tag larvae and juveniles to enable their identification when recaptured; 3) develop and test methods for the successful release of larvae and juveniles; 4) develop a monitoring strategy to estimate the abundance of released abalone through time; 5) quantify long-term survival and growth to provide minimum targets for stock enhancement; 6) determine the impact of releasing juveniles on wild populations; 7) provide a bio-economic analysis and; 8) provide recommendations for the implementation of a stock enhancement management strategy for H. rubra in NSW.
The release of larvae to natural reefs requires them to be exposed to a number of handling and transport processes. In laboratory experiments conducted in this thesis, greater proportions (commonly >75%) of larvae settled, metamorphosed and grew to larger sizes when exposed to settlement substrata for longer periods of time (>24 hours). There was a lower settlement response in the presence of water flow, although the addition of gamma-aminobutyric acid (GABA) increased the proportion of larvae that settled within short periods of time, i.e. 25 - 100% more in ≤60 sec.. Larvae were resistant to simulated handling and transport processes, indicating their utility for stock enhancement.
The tagging of larvae and juveniles is fundamental to assessing the success of an enhancement program. Hatchery-reared H. rubra larvae and juveniles were successfully batch-tagged. The tagging procedures provided an indelible mark, enabling the identification of individuals once recaptured, and unambiguous differentiation from wild conspecifics. Successful batch-tagging was also critical for the assessment of subsequent field experiments undertaken in this thesis. Larvae were batch-tagged with the epi-fluorescent dye, calcein. Laboratory experiments demonstrated that the tagged larval shell was clearly visible in the spire of juvenile shells after >250 days. The recapture of tagged and released larvae from natural reefs, >500 days after release, confirmed the persistence of this tag. A reliable and cost-effective method for batch-tagging juveniles was through the use of a commercial diet that resulted in the distinctive blue-green colouration of the shell. The presence of this blue-green colouration differentiated released juveniles from those in naturally occurring populations, could be observed with the naked eye, without the need for a UV light source, and persisted on the spire of individuals for >900 days.
Methods of releasing H. rubra larvae and juveniles were developed and tested in a series of laboratory and field experiments. A deployment pump that included a pressurised container and hose, was used to successfully release larvae to natural reefs. The addition of GABA and refrigeration during simulated transport, and the stage of release from the deployment pump, significantly affected the number of larvae delivered through the pump. The release of larvae to physical shelters on the reef significantly increased the numbers that settled, and their survivorship. There was added complexity in the process of releasing juveniles than with that for larvae. The use of a deployment device (PVC tube, ~300 x 125 x 65 mm), that was securely placed onto the substratum, was integral to the successful release of juveniles. Use of these devices in a standard release protocol ensured the limited physical handling of juveniles and provided a simple, cost effective and efficient method for the release of large numbers to areas of natural reef.
A monitoring strategy was developed and tested to enable accurate estimates of the abundance and therefore survival of released H. rubra ,of a variety of life history stages, to be measured. The abundance of H. rubra juveniles is difficult to accurately assess on natural reef because of their cryptic distribution among complex topography in rocky habitat. As a consequence, the precision and relative accuracy of methods to sample released abalone was examined in a series of field experiments, and included the dispersal of juveniles from deployment devices. The most accurate and precise estimates of the number of H. rubra surviving were detected using methods that disturbed the habitat, i.e. turning over boulders, within a release location, and multiple sampling approaches were required to measure the abundance of abalone of different sizes. For larvae, the collection of boulders provided more accurate estimates of abundance than samples taken using a venturi-lift. For juveniles, thorough searching of boulder substratum and more replicates provided more accurate estimates of abundance. Further, stratified sampling among habitats after natural disturbance revealed greater densities of H. rubra in 'solid habitat', and spatially stratified sampling indicated juveniles can disperse up to 10 m from their release point in <8 days.
The success of a stock enhancement strategy is determined by the net value it adds to a population. This necessitates estimates of the long-term survival and growth of released individuals, the impact released individuals have on the extant population, and the bio-economic feasibility of an enhancement strategy. Rates of survival and growth varied substantially among releases and locations. However, the long-term survival of batch-tagged and released larvae and juveniles demonstrated that local populations of abalone could be enhanced with significantly greater numbers of juveniles surviving at multiple release locations than at control locations after >2 years. The release of juveniles had no detectable affect on the mean total number of wild conspecifics or wild recruits over these time scales. Long-term survival of released larvae and juveniles was generally low (4% and where growth rates were higher than average rates reported in this research, or beach price exceeded $AUD 34.kg-1.
Low rates of long-term survival of larvae suggests their large-scale release is unlikely to provide a viable stand alone option to successfully enhance local populations of H. rubra. The survival and growth of released juveniles, to replicate locations, demonstrated that depleted local populations of H. rubra in NSW can be enhanced, and that a stock enhancement program can complement the NSW Abalone Fishery management strategy. The success of any large-scale stock enhancement program will be determined by the definition of its objectives. Outcomes from this thesis suggest that the greatest value of a stock enhancement strategy will be gained where its primary objective is to rebuild depleted populations, rather than optimise commercial yield through the release of individuals to overcome recruitment limitation or to harvest released individuals at a larger size. The decision to implement such a program, including explicit description of its primary objective, is required to be made among well-informed representatives of all stakeholders. Further, this decision needs to be made with a thorough understanding of the current biological structure of the populations, including the nature of population depletions, the economic status of the fishery and in light of current, complementary and alternative management arrangements that may provide comparative increases in net value
Batch-tagging blacklip abalone (Haliotis rubra) for identification of hatchery-reared individuals on natural coastal reefs in New South Wales, Australia
No full textThe identification of hatchery-reared larvae and juveniles is fundamental to assessing the success of their release when restocking. Hatchery-reared Haliotis rubra larvae and juveniles were successfully batch-tagged with distinct and persistent marks, enabling unambiguous differentiation from wild conspecifics when recaptured. Larvae were batch-tagged with the epifluorescent dye calcein. Experiments demonstrated that the batch-tagged larval shell was clearly visible in the spire of juvenile shells after 260 days. The recapture of batch-tagged and released larvae from natural reefs after 533 days at liberty also confirmed the persistence of this tag. A reliable and cost-effective method for batch-tagging juveniles was achieved with the use of an artificial diet that resulted in a distinctive blue-green coloration of the shell. This coloration differentiated released juveniles from wild conspecifics, was easily observed with the naked eye, and persisted on the spire of individuals for 777 days at liberty. These batch-tagging protocols allow large numbers of H. rubra larvae and juveniles to be distinctly tagged for long periods of time, enabling reliable estimation of survival after release and individual growth. It is likely that these techniques could also be applied to other abalone species
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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