1,720,953 research outputs found
On the spatial and temporal variability of upwelling in the southern Caribbean Sea and its influence on the ecology of phytoplankton and of the Spanish sardine (Sardinella aurita)
Full text linkThe Southern Caribbean Sea experiences a strong upwelling process along the coast from about 61°W to 75.5°W and 10-13°N. In this dissertation three aspects of this upwelling system are examined: (A) A mid-year secondary upwelling that was previously observed in the southeastern Caribbean Sea between June-July, when land based stations show a decrease in wind speed. The presence and effects of this upwelling along the whole southern Caribbean upwelling system were evaluated, as well as the relative forcing contribution of alongshore winds (Ekman Transport, ET) and wind-curl (Ekman Pumping, EP). (B) Stronger upwelling occurs in two particular regions, namely the eastern (63-65°W) and western (70-73°W) upwelling areas. However, the eastern area has higher fish biomass than the western area (78% and 18%, respectively, of the total small pelagic biomass of the southern Caribbean upwelling system). The upwelling dynamics along the southern Caribbean margin was studied to understand those regional variations on fish biomass. (C) The most important fishery in the eastern upwelling area off Venezuela is the Spanish sardine (Sardinella aurita). The sardine artisanal fishery is protected and only takes place up to ~10 km offshore. The effects of the upwelling cycle on the spatial distribution of S. aurita were studied. The main sources of data were satellite observations of sea surface temperature (SST), chlorophyll-a (Chl) and wind (ET and EP), in situ observations from the CARIACO Ocean Time-Series program, sardine biomass from 8 hydroacoustics surveys (1995-1998), and temperature profiles from the World Ocean Atlas 2005 used to calculate the depth of the Subtropical Underwater core (traced by the 22°C isotherm). The most important results of the study were as follows:
(A) The entire upwelling system has a mid-year upwelling event between June-August, besides the primary upwelling process of December-April. This secondary event is short-lived (~5 weeks) and ~1.5°C warmer than the primary upwelling. Together, both upwelling events lead to about 8 months of cooler waters (-3, averaged from the coast to 100 km offshore) in the region. Satellite nearshore wind (~25 km offshore) remained high in the eastern upwelling area (\u3e 6 m s-1) and had a maximum in the western area (~10 m s-1) producing high offshore ET during the mid-year upwelling (vertical transport of 2.4 - 3.8 m3 s-1 per meter of coastline, for the eastern and western areas, respectively). Total coastal upwelling transport was mainly caused by ET (~90%). However, at a regional scale, there was intensification of the wind curl during June as well; as a result open-sea upwelling due to EP causes isopycnal shoaling of deeper waters enhancing the coastal upwelling.
(B) The eastern and western upwelling areas had upwelling favorable winds all year round. Minimum / maximum offshore ET (from weekly climatologies) were 1.52 / 4.36 m3 s-1 per meter, for the western upwelling area; and 1.23 / 2.63 m3 s-1 per meter, for the eastern area. The eastern and western upwelling areas showed important variations in their upwelling dynamics. Annual averages in the eastern area showed moderate wind speeds (6.12 m s-1), shallow 22°C isotherm (85 m), cool SSTs (25.24°C), and phytoplankton biomass of 1.65 mg m-3. The western area has on average stronger wind speeds (8.23 m s-1) but a deeper 22°C isotherm (115 m), leading to slightly warmer SSTs (25.53°C) and slightly lower phytoplankton biomass (1.15 mg m-3). We hypothesize that the factors that most inhibits fish production in the western upwelling area are the high level of wind-induced turbulence and the strong offshore ET.
(C) Hydroacoustics values of Sardinella aurita biomass (sAsardine) and the number of small pelagics schools collected in the eastern upwelling region off northeast Venezuela were compared with environmental variables (satellite products of SST, SST gradients, and Chl -for the last two cruises-) and spatial variables (distance to upwelling foci and longitude-latitude). These data were examined using Generalized Additive Models. During the strongest upwelling season (February-March) sAsardine was widely distributed in the cooler, Chl rich upwelling plumes over the wide (~70km) continental shelf. During the weakest upwelling season (September-October) sAsardine was collocated with the higher Chl (1-3 mg m-3) found within the first 10 km from the upwelling foci; this increases Spanish sardine availability (and possibly the catchability) for the artisanal fishery. These results imply that during prolonged periods of weak upwelling the environmentally stressed (due to food scarceness) Spanish sardine population would be closer to the coast and more available to the fishery, which could easily turn into overfishing. After two consecutive years of weak upwelling (2004-2005) Spanish sardine fishery crashed and as of 2011 has not recovered to previous yield; however during 2004 a historical capture peak occurred. We hypothesize that this Spanish sardine collapse was caused by a combination of sustained stressful environmental conditions and of overfishing, due to the increased catchability of the stock caused by aggregation of the fish in the cooler coastal upwelling cells during the anomalous warm upwelling season
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
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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