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Helseovervåking i lakseoppdrett : en viktig del av helsestyringen
Get PDFMortality represents a major challenge in the salmon farming industry. In Norway
the mortality in the marine phase of the salmon production cycle has been 15-20%
annually the recent years. This situation is not sustainable for the fish, the farmers
or society. To prevent mortality throughout the production cycle, fish-groups at risk
of deteriorating health must be identified early, regarding both disease development
and stage in the production cycle. Hence, robust population health monitoring
methods are needed, which will provide farmers with information to make
knowledge-based decisions to improve fish health.
The aim of the thesis was to investigate monitoring methods that can be used to
improve fish health management in salmon farming. This was approached through
four studies investigating mortality patterns, cause-specific mortality classification,
gill mucous cell count and gill mucus microbial composition, respectively, as
potential factors relevant to monitoring fish health status in salmon farming.
Mortality patterns in salmon farming were investigated through a retrospective
study of fish-groups from two commercial fish farming companies, describing the
cause-specific mortality during the production cycle and investigating sources of
variation in mortality between the hatchery, marine farm, and the fish-group. Most
of the variation in mortality was attributed to the fish-group. Based on the
information from the cause-specific mortality registrations, smolt-related mortality
was found to be the major cause of death during the first six months of production,
while handling and treatment was the overall dominating cause of death in the full
production cycle. However, this varied extensively between the fish-groups.
The second study further explored the system of cause-specific mortality and
suggested a unique classification code. A system for classifying causes of mortality
based on underlying cause was created for salmon farming inspired by the human
mortality classification system. The proposed standard has a three-level hierarchical
structure of mortality causes. This accommodates different levels of details when
mortality causes are registered and enhance the information possible to retrieve
from the system.
To target early responses of the immune system, variation in gill mucous cell count
was studied as a potential method of monitoring health status. Salmon presmolt
from six commercial hatcheries was sampled and mucous cells were histologically
quantified based on certain criteria. The counts varied among both fish and farms.
When “farm” was included as an independent variable in a regression model the
proportion of variation in mucous cell counts explained by the model was twice as
high compared to when only fish size was included. This indicates that the variation
depends on farm-related factors.
A subset of the fish (from four recirculating aquaculture system (RAS) facilities)
included in the study of mucous cells was also sampled for gill mucus for microbial
composition analyses using 16S rRNA gene sequencing. Quantification of extracted
bacterial DNA in the gill mucus samples showed low levels in general, but fish from
one farm had considerably more bacterial DNA compared to the others. Samples
from the same farm were also compositionally different based on beta diversity
metrics, compared to the others as one group. Assessed by the Shannon index as an
outcome in a regression model, sources of variation attributed most variation to the
individual fish, suggesting gill microbial structure was linked to the individual fish.
No associations between gill microbial diversity and specific production parameters
were detected.
In conclusion, cause-specific mortality classification was found to identify important
causes of mortality in the production cycle, thus providing farmers with substantial
health information with limited effort and at little cost. The tool can further be
applied at desired level of detail and adapted to the needs of each farmer. Novel
methods of gill mucous cell count and microbial composition identifies variation
among farms and individual fish for the different measured parameters. This
variation can potentially be exploited to detect early signs of reduced health in the
fish. However, further studies are necessary to establish the causal association
between these factors and fish health before they can be used in systematic
monitoring of health in salmon farming.Dødelighet i oppdrettsnæringen er en stor utfordring i dag. Norsk lakseoppdrett har de siste årene hatt mellom 15 og 20% dødelighet i sjøfasen. Dette er ikke bærekraftig, hverken for fisken, oppdretterne eller samfunnet. For å forebygge dødelighet gjennom produksjonssyklusen må fiskegrupper som har økt risiko for dårligere helse identifiseres tidlig. Derfor er robuste overvåkingsmetoder på populasjonsnivå nødvendige, det vil gi oppdretterne nyttig informasjon for å kunne ta kunnskapsbaserte avgjørelser i arbeidet med å forbedre helsesituasjonen til fisken.
Målet med doktorgraden var å undersøke overvåkingsmetoder som kan brukes til å forbedre helsestyringen i oppdrettsnæringen. Dette ble gjort ved å undersøke mulige faktorer som kan gi informasjon om helsestatus, henholdsvis dødelighetsmønster, årsaks-spesifikk dødelighetsklassifisering, slimceller på gjellene og mikrobiell sammensetting på gjellenes slimlag
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
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
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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