1,721,002 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
Current and novel tools in the health assessment of large whales
Full text linkDissertation (Ph.D.) University of Alaska Fairbanks, 2021Alaskan marine ecosystems are undergoing unprecedented change and species are facing increasingly variable and potentially inhospitable habitats. As top predators, marine mammals serve an important role as sentinels of ecosystem health. With their high site fidelity, abundant numbers, coastal presence and role as a top predator, humpback whales (Megaptera novaeangliae) provide a meaningful view into current ecosystem conditions and processes. In order to tap into their usefulness as bioindicators the basic physiology of humpback whales needs to be understood. Physiological indices can provide valuable information about fecundity, survival, health and population age structuring which is fundamental to cetacean research and population management. However, such information is often difficult to obtain from wild cetaceans as they surface infrequently and often live in remote or logistically challenging locations. As such, few methods currently exist for the assessment of physiological parameters of free ranging, large cetaceans. This dissertation paired existing methods of physiological examination with novel approaches in order to better understand the basic physiology and overall health of humpback whales. Specifically, six enzyme immunoassays were validated for use in humpback whales for progesterone, testosterone, cortisol, corticosterone, aldosterone and DHEA-S, an algorithm termed "Morphometer" was developed to automate the process of measuring and analyzing morphometric measurements, and hormones and body condition metrics were paired to determine whether pregnancy status can be detected from aerial photographs. This project seeks to lay the groundwork for long term monitoring of humpback whales that can provide critical information to managers. By using baseline physiological indices and tools to rapidly analyze these metrics that I developed here, managers and researchers will be able to analyze current and future samples within a longitudinal context and make management decisions based on more accurate biological information for these populations.Alaska Whale Foundation (AWF) and the Lindblad Expeditions-National Geographic Conservation FundGeneral introduction -- Chapter 1: Testosterone trends within and across seasons in male humpback whales (Megaptera novaeangliae) from Hawaii and Alaska -- Chapter 2: Corticosterone in central north Pacific male humpback whales (Megaptera novaeangliae): pairing sighting histories with endocrine markers to assess stress -- Chapter 3: Automated pixel-based tool for morphometric assessment of large whale populations -- Chapter 4: Aerial sonogram: pairing endocrine markers with morphometrics to detect reproductive state in humpback whales (Megaptera novaeangliae) -- General conclusion -- Appendix
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
Population dynamics of Pacific herring and humpback whales, Sitka Sound, Alaska 1981-2011
Full text linkDissertation (Ph.D.) University of Alaska Fairbanks, 2015Humpback whales are a major predator in Sitka Sound, possibly consuming as much as a half-ton of Pacific herring per day. These large migratory baleen whales congregate in Sitka Sound to feed on schools of Pacific herring which spawn in April. In recent decades humpback whale abundance has increased tremendously in Sitka Sound after recovering from near extinction due to commercial whaling. In order to assess the long-term impact on herring by humpback whales, I estimated humpback whale abundance from 1981 to 2011. To do so I developed a Bayesian mark-recapture method for small sample sizes. I also modified a multi-strata Hilborn model to account for sporadic availability of whales in Sitka Sound. The multi-million dollar sac roe fishery in Sitka Sound is managed by the Alaska Department of Fish and Game (ADF&G) with an Age-Structured Assessment model (ASA). I modified the standard ASA model by including the humpback whale abundance estimates as a covariate for herring natural mortality. I found that there is no significant effect of humpback whales on herring mortality. In fact, both Pacific herring and humpback whale abundance have increased together, reaching their maximum values in 2011. This suggests that some other factor, perhaps better marine survival for both species, is driving their upwards trend
Considering predation by humpback whales in the mystery of the failed recovery of Pacific herring in Prince William Sound, Alaska
Full text linkThesis (M.S.) University of Alaska Fairbanks, 2011In Prince William Sound (PWS) in the early 1990s, biomass of an important forage species, Pacific herring (Clupea pallasii), crashed and has since failed to recover. This thesis explores the role that predation by humpback whales (Megaptera novaeangliae) may have in limiting this recovery. This was done by modeling the historic (1980-2009) relationship between these two species using existing data. Mark-recapture estimates of abundance were combined to form the first time series of humpback whale abundance for this area. This time series was then integrated into the age-structured assessment model used by Alaska Department of Fish and Game to manage herring biomass in PWS by adding annual estimates of humpback whale abundance as a covariate to herring mortality. The current (2009) humpback whale population estimate was 191 (SE 32) representing a rate of increase of 4.5% annually. Humpback whale abundance helped to explain variation in mortality of older (ages 5+) herring only, with humpback whales accounting for as much as one-third of all mortality in these ages. However, retrospective analyses of the updated model show that recruitment, and not predation on adult herring, is the most influential factor limiting the recovery of herring in PWS.Exxon Valdez Oil Spill Trustee Council, Cooperative Institute for Arctic Research, National Oceanic and Atmospheric Administration cooperative agreement NA17RJ1224 with the University of Alaska1. First historical time series of estimated humpback whale (Megaptera novaeangliae) abundance in Prince William Sound -- 2. The ecological importance of humpback whale predation on herring biomass in Prince William Sound as determined by model covariation
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
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