1,721,004 research outputs found
Reetablering av laks i Vefsna. Årsrapport 2015
Full text linkEspen Holthe, Arne J. Jensen, Marius Berg, Gunnbjørn Bremset & Jan Gunnar Jensås 2016. Reetablering av laks i Vefsna. Årsrapport 2015. - NINA Rapport 1245. 37 s.
Veterinærinstituttet (VI) og Norsk institutt for naturforskning (NINA) har på oppdrag fra Statkraft Energi AS i fellesskap ansvaret for evalueringen av tiltak som utføres i Vefsna i forbindelse med reetablering av fiskebestandene av laks og sjøørret etter bekjempelsestiltak for å fjerne parasitten Gyrodactylus salaris fra vassdraget. Oppdraget har en varighet på fem år (2014-2018), og dette er den andre årsrapporten fra prosjektet.
Arbeidet omfatter: 1) analyse av rognutleggingen, inkludert kartlegging av overlevelse av utlagt rogn, 2) ungfiskundersøkelser på utvalgte stasjoner i vassdraget, 3) registrering og analyse av livshistorieparametere på tilbakevandrende voksen laks og 4) gytefiskregistreringer (ved drivtellinger).
Overlevelsen hos den utsatte rogna fram til den klekker og forlater Witlock-Vibert boksen var i gjennomsnitt 98,2 % for 100 utlagte bokser, dette vurderes som et meget godt resultat.
Det ble utført tetthetsberegninger av ungfisk på ni stasjoner i Vefsna nedenfor Laksforsen. Tett-heten av ungfisk, både laks og ørret, var i 2014 og 2015 betydelig lavere enn på 1970-tallet, før G. salaris ble påvist i vassdraget, mens veksten var bedre enn på 1970-tallet. Begge disse faktorene viser at vassdraget foreløpig ikke er fullrekruttert, og at det er plass for betydelig flere fisk i elva.
All utsatt fisk ble merket med fargestoffet Alizarin på øyerognstadiet. Dette fargestoffet kan på senere livsstadier detekteres i otolittene, og dermed kan utsatt fisk skilles fra naturlig produsert fisk. Deteksjon av Alizarinmerke i otolitter viste at andelen av utsatt laks blant årsyngelen i Vefsna var 57,9 %, mens andelen utsatt laks blant ettåringene var 14,3 %. Andelen merkede lakseunger med alder to år (2+) var på 23,9 %, hos samme årsklasse i 2014 var merkeandelen 56,1 %. Ut fra disse andelene er det grunn til å tro at utsettingene av foret og ufôret yngel har hatt godt tilslag i Vefsna. Hos årsyngelen dominerte det utsatte materialet, og sammen med smoltutset-tingene som gjennomføres er det sannsynlig at utsatt materiale fra genbanken vil dominere i voksenfiskbestanden de nærmeste årene.
Laksens tilvekst i sjøen var bedre for naturlig produsert enn for utsatt fisk, men likevel dårligere enn på 1970-tallet. Otolittundersøkelser av 67 voksne laks i 2015 viste at 53,7 % var utsatt. I årsklassene av voksen laks som kan spores til reetableringsprosjektet ut fra aldersanalyser, var 35 av 44 individer (79,5 %) merket.
I oktober 2015 ble det under gytefisktelling registrert 862 voksne laks, 1780 voksne sjøørret og 190 umodne sjøørret på elvestrekningen mellom Laksforsen (øvre vandringshinder) og Kvalfor-sen. De største mengdene gytelaks var i de to øverste vassdragsavsnittene, og spesielt stor forekomst av laks ble registrert i vassdragsavsnittet mellom Laksforsen og Nedre Laksforsen (52 % av alle observasjoner). I øvrige vassdragsavsnitt varierte registreringene mellom 31 og 79 individer, noe som tilsvarer tettheter mellom 10 og 40 laks per kilometer elvestrekning. Smålaks var den klart største størrelsesgruppen fulgt av mellomlaks (henholdsvis 73 og 23 % av registeringene). Sammenlignet med høsten 2014 ble det registrert nesten dobbelt så mye voksen laks og nesten tre ganger så mye voksen sjøørret. Mengden umoden sjøørret var imidlertid betydelig lavere i 2015 sammenlignet med 2014, noe som skyldes en reduksjon i antall ungfisk av sjøørret som følge av utryddingstiltakene i 2011 og 2012.The Norwegian Veterinary Institute (VI) and Norwegian Institute for Nature Research (NINA) have the joint responsibility for evaluating measures to reestablish the populations of Atlantic salmon and anadromous brown trout in the River Vefsna following the removal of the parasite Gyrodactylus salaris from the watershed. The present report is the second annual report form this project.
This work included: 1) analyzing survival of eggs and alevins following stocking of eggs in the river, 2) quantitative electrofishing for fry and parr at nine localities in the river, 3) analyzing age and marine growth of adult Atlantic salmon, and 4) recording the spawning population of Atlantic salmon and sea trout by drift diving.
The mean survival of eggs stocked in the river was estimated at 98.2%, for 100.000 stocked eggs in 2015, the result is considered very good.
In 2014 and 2015, the densities of juvenile fish, both Atlantic salmon and brown trout, were con-siderably lower than during the 1970s, i.e. before G. salaris was detected in the river, while the growth rate was higher than during the 1970s. Both these parameters demonstrate that the river is still far from fully recruited by juvenile fish.
Eggs of all stocked fish were marked with Alizarin. Detection of Alizarin marks in otoliths showed that the overall amount of stocked juvenile salmon at 0+ age was 57.9%, while the proportion of stocked juvenile salmon at 1+ age was 14.3%. These proportions indicate that the stocked salmon eggs and unfed fry have had good survival in Vefsna. In the 0+ population, stocked fish dominated. Together with the transfer of smolts carried out in the years from 2013, it is likely that stocked material from the gene bank will dominate in the adult salmon population in the next years.
The growth rate the first year at sea was higher for wild than for cultivated individuals of Atlantic salmon. This growth was, however, lower than for wild salmon caught during the 1970s. Otolith analyzes of 67 adult salmon in 2015 showed a marked share of 53.7%. In adult fish that can be traced back to the restoration program, by age, 35 out of 44 individuals (79.5%) had Alizarin marks in their otoliths.
In October 2015, a total of 862 adult salmon, 1780 mature and 190 immature sea trout were observed during a drift diving survey between the waterfalls Laksforsen (migration barrier) and Kvalforsen. The highest occurrence and density of adult salmon was recorded in the uppermost 5 km, and in particular inside the river stretch between Laksforsen and Nedre Laksforsen (52% of all observations). Compared to the previous autumn there were recorded almost twice as many adult salmon and almost three times as many mature sea trout. Immature sea trout, how-ever, were at only a 10 percent level compared to the previous year. The most likely explanation for this significant decline is that some year classes of sea trout were eradicated of the rotenone treatment some years ago.© Norsk institutt for naturforskning. Publikasjonen kan siteres fritt med kildeangivelse
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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