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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
Genetisk karakterisering av fettsyresammensetning i melk
Get PDFBovine milk is a highly regarded food source. Still, some milk fatty acids may have unfavourable health effects and can influence manufacturing properties of dairy products. Individual milk fatty acids show moderate heritabilities, and better knowledge of the underlying genes may be used to speed up the genetic progress of the traits and provide dairy products of higher quality and nutritional value. In this thesis, mutations underpinning variation in bovine milk fat composition in Norwegian Red cattle was explored, with emphasis on fatty acids produces de novo in the mammary gland, and the two dominant acids in bovine milk, palmitic (C16:0) and oleic acid (C18:1cis9).
Paper I established the calibration equations to predict the fatty acid profiles from Fourier- transform infrared spectroscopy (FTIR) data used to estimate variance components for individual and groups of fatty acids. Most major fatty acids were predicted rather accurately. Short and medium length saturated acids were, in general, more heritable than longer and unsaturated acids. A genome-wide association analysis performed on both individual acids and groups of acids revealed a region on chromosome 13 with strong influence on levels of the even chain fatty acids C4:0 to C14:0. The association was first thought to be related to the gene acyl-CoA synthetase 2 (ACSS2), but subsequent fine-mapping highlighted another close- by gene; nuclear receptor coactivator 6 (NCOA6).
Paper II aimed to further explore the genetic basis of the de novo synthesised acids, extending the analysis with a larger data set, imputed sequence variants and mammary gene expression data. Progestagen Associated Endometrial Protein (PAEP) on Bos taurus autosome (BTA)11 was strongly associated with the content of the shortest acid C4:0, acetoacetyl-CoA synthetase (AACS) on BTA17 was associated with the content of C4:0 and C6:0. NCOA6 on BTA13 was associated with acids of intermediate chain lengths (especially C8:0), whereas fatty acid synthase (FASN) was mainly associated with the longest acid, C14:0. All suggested positional candidate genes were expressed in the bovine udder during lactation.
Paper III focused on C16:0 and C18:1cis-9, possibly having opposing effects on human cardiovascular health and relevance for dairy manufacturing properties. A set of variants within and close to PAEP on BTA11 shown to affect the ratio between the two acids were identified. The variants were further shown associated with PAEP gene expression and levels of the translated protein β-lactoglobulin. Breeders may use the Paper III findings to promote milk with a healthier fatty acid profile and positive effect on cheese-making properties.Kumelk er regnet som en god human ernæringskilde. Samtidig kan nivået av enkelte fettsyrer i melk ha uheldige helsekonsekvenser, i tillegg til å kunne påvirke meieriprodukters produksjonsegenskaper. Studier har vist at konsentrasjonen av melkefettsyrer er arvbar, og bedre kunnskap om de underliggende gener og varianter vil kunne utnyttes i avl for å kunne oppnå genetisk fremgang for denne egenskapen. I denne avhandlingen ble mutasjoner med påvirkning på fettsyresammensetningen i melk undersøkt, med fokus på syrer syntetisert de novo i jur, og de to vanligste fettsyrene i melk; palmitinsyre (C16:0) og oljesyre (C18:1cis9).
Artikkel I etablerte kalibreringslikningene nødvendig for å predikere fettsyreprofiler og beregne fettsyrenes arvbarhet ved bruk av FTIR-spektra. De fleste frekvente melkefettsyrer ble predikert med tilstrekkelig nøyaktighet. Mettede fettsyrer med kort og medium kjedelengde hadde generelt høyere arvbarhet en lengre og umettede syrer. En assosiasjonsstudie, utført med både fettsyregrupper og individuelle fettsyrer, pekte mot en region på kromosom 13 med sterk effekt på nivået av de likekjedede fettsyrene C4:0 til C14:0. Genet acyl-CoA synthetase 2 (ACSS2) ble først pekt ut som det beste kandidatgenet, men videre finkartlegging pekte mot det nærliggende genet nuclear receptor coactivator 6 (NCOA6).
I artikkel II ble den genetiske bakgrunnen for de novo-syntetiserte fettsyrer videre studert. Analysen identifiserte sterke assosiasjoner mellom genene Progestagen Associated Endometrial Protein (PAEP) og acetoacetyl-CoA synthetase (AACS) og innhold av C4:0- C6:0, NCOA6 og syrer med mellomlang kjedelengde (C6:0-C12:0) og fatty acid synthase (FASN) ble funnet sterkt assosiert til innhold av C14:0. Alle foreslåtte kandidatgener ble funnet uttrykt i jur.
Artikkel III fokuserte på C16:0 og C18:1cis9, de to mest frekvente fettsyrene i melk, som har betydning for både human helse og melkeproduksjonsegenskaper. Det ble identifiserte et sett varianter i og nær genet PAEP på kromosom 11, med motsatt effekt på palmitin og oljesyre. De samme variantene ble også assosiert til redusert ekspresjon av PAEP og redusert nivå av det translaterte proteinet β-lactoglobulin. Funnene fra artikkel III kan utnyttes til å avle frem melkekyr med sunnere melkefettsyreprofil og positive effekter på melkens ysteegenskaper
Identification and characterisation of genes associated with milk fatty acid composition
No full textSammendrag
Selv om helseeffekten av melkekonsum er omdiskutert, består helmelk av en betydelig fraksjon
mettede fettsyrer som i seg selv har vist seg å være forbundet med hjertesykdom og overvekt.
Tidligere studier i Norsk Rødt Fe har påvist en rekke områder i genomet (QTLer) som påvirker
fettsyresammensetningen i melk. To av de mest aktuelle områdene på henholdsvis kromosom
13 og kromosom 26 fra storfegenomet, ble valgt ut. Ved bruk av systematisk søk etter SNPer,
genotyping av utvalgte markører, samt assosiasjonskartlegging i områdene, håpet man å finne
individuelle gener og helst kausale mutasjoner assosiert med fettsyresammensetning i melk.
Både enkelt-SNP-analyser og haplotypeanalyser tyder på at en polymorfisme i genet "nuclear
receptor coactivator 6" (NCOA6) er ansvarlig for variasjonen korte fettsyrer syntetisert de novo
på kromosom 13. Tidligere studier har plukket ut "acyl-CoA synthetase short-chain family
member 2" (ACSS2) som det mest sannsynlige kandidatgenet for denne QTLen, noe data i
denne oppgaven ikke viser. Ingen av de genotypede SNPene i NCOA6 viste seg å gi en åpenbar
funksjonell endring i form av eksempelvis endret aminosyresammensetning. Videre studier er
derfor nødvendig for om mulig å avklare om SNPene som er studert kan forårsake andre
funksjonsendringer.
På kromosom 26 ble det funnet svake og inkonsekvente signaler, noe som mest sannsynlig
skyldes en kombinasjon av at de kausale mutasjoner segregerer i for lav frekvens, og at det
eksisterer flere QTLer som kan påvirke egenskapene som er undersøkt. Det er derfor nødvendig
å genere et større datamateriale for å med større nøyaktighet avdekke om QTL er reel og hva
den eventuelt underliggende årsaken til en slik QTL kan være. Abstract
The health effect of milk consumption is disputed, but milk does contain a significant amount of
saturated fatty acids associated with heart disease and obesity.
Earlier studies in Norwegian Red Cattle have identified a number of QTLs associated with milk
fatty acid composition. Two of the most promising areas from chromosome 13 and 26 from the
bovine genome were selected for further analysis, hoping to find individual genes and if possible
causal mutations associated with milk fatty acid composition.
The results of this thesis suggest that a polymorphism in the gene nuclear receptor coactivator 6
(NCOA6) is responsible for observed variation in short chain fatty acids synthesized de novo on
chromosome 13. Earlier studies have pointed out acyl-CoA synthetase short-chain family
member 2 (ACSS2) as a candidate in the area, but results in this thesis do not support this. None
of the examined SNPs were identified as obvious causal mutations, and further study is needed
to examine the cause of the variation.
On chromosome 26, weak and inconsistent signals were found. Further studies where larger
datasets is utilized is probably needed to resolve if the QTLs observed were real and what the
underlying cause might be
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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