1,720,997 research outputs found
Ecopath 30 years : modelling ecosystem dynamics : beyond boundaries with EwE
No full textMarine and coastal ecosystems provide multiple benefits that are fundamental to human wellbeing, but human actions are disrupting and impacting the Earth's ecosystems at an alarming rate. The Ecopath approach was designed to understand the impact of the wide range of anthropogenic pressures that are exerted on the oceans, and of management options for countering these, and it has over the last thirty years grown into a complex and capable modelling framework: "Ecopath with Ecosim" - with Ecospace added on. Exciting new developments of the approach are contributing to address critical and complex issues related to the health of marine ecosystems such as invasion of species, illegal fishing activities, climate change and the development of new activities (e.g., aquaculture and infrastructure development) in coastal areas. This Special Issue presents new findings from selected case studies around the world using advanced features of Ecopath with Ecosim that were presented at the International Conference "Ecopath 30 Years Modelling ecosystem dynamics: beyond boundaries with EwE" (November 2014, Barcelona, Spain). These contributions showcase new capabilities and findings of Ecopath with Ecosim models applications. Together these papers show that a range of diverse ecological, economic, social and governance drivers are often interacting at dynamic and temporal scales to modify marine resources, which underlines that managing marine ecosystems needs a continuous effort to integrate multiple processes
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
Age and growth estimation for the white shrimp, Penaeus setiferus, from the offshore fishery of the northwestern Gulf of Mexico
No full textTime recovery for exploited fish populations based on surplus yield models
Get PDFExploitation, Population dynamics, Mathematical models, Baja California, Mexico, Octopus maya, Epinephelus morio, Haliotis corrugata
Age and growth estimation for the white shrimp, Penaeus setiferus, from the offshore fishery of the northwestern Gulf of Mexico
Get PDFGrowth and seasonal recruitment of Octopus maya on Campeche Bank, Mexico
Get PDFA study of growth and seasonal recruitment of the cephalopod Octopus maya on Campeche Bank, Mexico, was conducted, based on catch at size data sampled from 1983 to 1988. The parameters of a seasonally oscillating version of the von Bertalanffy growth function and total mortality estimates were obtained via the ELEFAN software. It was found that when recruitment occurs early in the year, the growth curve of the next year does not display seasonal oscillations, and conversely. Total mortality estimates ranged from Z = 2.6 to Z = 6.3/year
Population tendencies of a pelagic coastal multispecies fishery: responses to changes of the fishing effort; Tendencias poblacionales de una pesqueria pelagico-costera multiespecifica: respuestas a cambios en el esfuerzo de pesca
No full textTitle and abstract are in English and Spanish; article is in Spanish
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