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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
Embryodød hos Norsk Rødt Fe : subklinisk endometritt og paternal innvirkning på tidlig embryoutvikling
Full text linkThe productivity in the dairy cattle industry is highly dependent on fertility. In the last decades, an alarming decrease in the reproductive capacity has been detected in most dairy cattle breeds. Subfertility in dairy cattle is multifactorial, and the most common mechanism for failure of pregnancy is embryo loss which occurs within the first 42 days of gestation. Embryo survival depends both on the environment in the reproductive tract of the mother, and the quality of the embryo as such. Hence, embryo loss may be attributable to any negative impact along the developmental axis and determined by both maternal and paternal impact.
Norwegian red (NR) is notable for its good reproductive performance, which is probably a result of emphasis on fertility and health traits in the breeding program since the 1970’s. With the implementation of genomic selection in the breeding strategy, interest in new phenotypes that can add information on fertility and health has been increasing. The strategy also has a new focus on embryo production, which requires a high level of knowledge concerning all aspects of the embryo.
The overall aim for this thesis was to gain knowledge about factors affecting embryo loss in NR. To do this, specific knowledge gaps related to both maternal and paternal aspect were targeted. In the cow, we provided information about cytological endometritis (CYTO) at artificial insemination (AI) in NR through a prospective cohort field trial of 1,648 cows in 116 herds, using the cytotape technique. Here, prevalence, effect on fertility and embryo loss, and risk factors for the condition was reported. This was complemented by a heritability estimate for the condition using data from the same population. Further, we investigated the uterine microbiota at AI in NR using a smaller study population from one herd. To investigate the paternal contribution to the early embryo, we performed a transcriptome study of embryos derived from bulls with high and low field fertility, respectively.
The prevalence of CYTO was 28% at AI, when the condition was defined by a 3% cutoff of the proportion of polymorphonuclear cells in cytological smears. The prevalence was higher than previously described at AI in other breeds. We reported a negative association between pregnancy incidence to first AI and CYTO. However, the overall pregnancy incidence to first AI was high, suggesting that the biological effect of this condition appears to be modest in comparison with results from other breeds. We speculate that an advantageous uterine immunology or perhaps certain traits in the microbiota could be the explanation for this outcome. The detected risk factors for CYTO were AI personnel, interval from calving to first AI, vaginal mucus condition, red blood cells in sample, barn type, and season. Late embryo loss and fetal loss was not associated with CYTO at first AI, suggesting that decreased fertility in CYTO positive cows is a result of either early embryo loss or fertilization failure.
CYTO detected at AI was indicated to be heritable in NR by a trait definition of 5% polymorphonuclear cells. The heritability estimate was 0.04 and comparable to estimates of other diseases and disorders included in the total merit index for NR. Hence, CYTO can be considered as a new phenotype for fertility. With future development of a more feasible method to diagnose CYTO, it has the potential to be used for breeding purposes.
The uterine endometrial microbiota at AI was investigated at a superficial level with a cytobrush sample, and at a deep level with a biopsy sample. The microbiota from both sites was compared to the findings in vaginal swabs. In the biopsy samples, we found a high relative abundance of Oscillospiraceae UCG-005, Bacteroidetes_vadinHA17, Ruminococcus, Bacteroides, Alysiella and four different genera of the family Lachnospiraceae. These taxa were barely present in the other sample types, and not present in the negative extraction control. Streptococcus was highly abundant in both cytobrush and vaginal swabs, and Escherichia-Shigella was detected in mainly the vaginal swabs. The cytobrush samples and the vaginal swabs shared a similar taxonomic composition, suggesting that vaginal swabs may suffice to describe the surface-layer uterine microbiota at estrus. Interestingly, Fusobacteriota, which is associated with the development of metritis and purulent vaginal discharge, and a common finding in the uterine microbiota in other breeds, was not detected in any of the sample types. The biopsy samples were qualitatively different and more even than that of cytobrush and vaginal swab samples. We hypothesize that the deep layer endometrial microbiota might be associated with diseases and disorders in the uterus, even when superficial layer microbiota does not show such a correlation.
Embryos derived from bulls of high or low field fertility had a differing gene expression in genes linked to cholesterol metabolism, cytokine signaling, regulation of apoptosis, adhesion and attachment in placental development, formation of tight junctions, and regulation of redox activity. These are all processes or pathways that are known to be crucial for embryo development at the blastocyst stage and around attachment.
The collected results presented in this thesis are valuable as we continue to explore the underlying mechanisms of fertility in dairy cattle. For NR, the results are applicable for breeding and management recommendations, as well as in herd health investigations. This contributes to maintaining the current status of NR as a high fertility breed, and possible future improvements.Produktivitet i melkeindustrien er i høy grad avhengig av dyrenes fruktbarhet. I løpet av de siste tiårene, har det blitt rapportert en markert nedgang i reproduktive resultater hos de fleste melkeraser. Lav fruktbarhet hos melkeku skyldes flere faktorer, og den vanligste årsaken til uteblitt drektighet er embryodød de første 42 dagene etter paring. Embryoets overlevelse er avhengig av både miljø i morens reproduksjonsorganer og kvaliteten av embryoet selv. Embryodød kan derfor skyldes enhver negativ innvirkning langs hele utviklingsaksen og påvirkes av både maternale og paternale aspekter.
Norsk Rødt Fe (NR) er en rase med svært god fruktbarhet. Dette er sannsynligvis et resultat av avlsprogrammets vektlegging av egenskaper koblet til fertilitet helt siden 1970-årene. Med implementering av genomisk seleksjon i avlsstrategien, har man sett en øket interesse for nye fenotyper som kan inkluderes i avlsarbeidet. I den nye strategien satses det også på embryoproduksjon. Dette krever et høyt nivå av kunnskap om alle aspekter av embryoutvikling.
Det overordnede målet for denne avhandlingen var å innhente kunnskap om faktorer som påvirker embryodød hos NR. For å oppnå dette, rettet vi fokus mot spesielle kunnskapshull relatert til både maternal og paternal innvirkning. Hos mordyret, presenterte vi ny informasjon om cytologisk endometritt (CYTO) ved kunstig sædoverføring (KS) hos NR. Data ble samlet inn i felt fra 1648 kyr i 116 besetninger med hjelp av cytotape og brukt til en prospektiv kohortstudie. Her rapporterte vi prevalens, effekt på fertilitet og embryo død, og risikofaktorer koblet til tilstanden. Dette ble videre komplettert med en beregning av estimert arvbarhet for CYTO med data fra den samme populasjonen. Videre undersøkte vi uterin mikrobiota ved KS hos NR i en mindre studiepopulasjon fra én besetning. For å undersøke det paternale bidraget i tidlig embryoutvikling, gjennomførte vi en transkriptomstudie av embryo med opphav fra okser med henholdsvis høy eller lav feltfruktbarhet.
Prevalensen for CYTO var 28% ved KS når tilstanden ble definert ved en grense på 3% av polymorfonukleære celler i celleutstryk. Den rapporterte prevalensen var høyere enn det som tidligere har blitt beskrevet ved KS for andre raser. Vi fant en negativ assosiasjon mellom drektighet etter første KS, og CYTO. Til tross for dette, var den totale drektighetsinsidensen etter første KS høy, hvilket indikerer at den biologiske effekten av denne tilstanden hos NR tilsynelatende er moderat sammenlignet med andre raser. Basert på disse funnene, har vi diskutert om resultatene kan være koblede til en fordelaktig uterin immunologi, eller muligvis spesielle trekk i uterin mikrobiota hos NR. Risikofaktorer for CYTO var inseminør, intervall fra kalving til første KS, karakteristika ved vaginal utflod, røde blodlegemer i prøven, fjøstype og sesong. Sen embryodød og fosterdød var ikke assosiert med CYTO ved første KS, hvilket indikerer at forstyrrelser i fertiliteten hos CYTO positive kyr er et resultat av enten tidlig embryodød eller uteblitt fertilisasjon.
CYTO ved AI er tilsynelatende arvelig hos NR når egenskapen blir definert ved en grense på 5% polymorfonukleære celler. Arvbarheten ble estimert til 0.04, hvilket kan sammenlignes med andre tilstander og sykdommer som blir inkludert i samlet avlsverdi for NR. CYTO kan bli betraktet som en ny fenotype for fertilitet. Under forutsetning av at det utvikles en mer gjennomførbar metode for å diagnostisere CYTO, har egenskapen potensiale til å bli brukt i avlsprogrammet for NR.
Den uterine mikrobiotaen ved KS ble undersøkt i overfladisk endometrium med en cytobrush prøve, samt i dypere endometrium med en biopsi. Mikrobiota fra både overfladisk og dyp prøve ble sammenlignet med funn fra vaginalsvaber. I biopsiprøvene ble de funnet en høy relativ tilstedeværelse av Oscillospiraceae UCG-005, Bacteroidetes_vadinHA17, Ruminococcus, Bacteroides, Alysiella og fire forskjellige genera av familien Lachnospiraceae. Disse taxa var nesten ikke til stede i de andre prøvetypene, og ble ikke funnet i negative ekstraksjonskontroller. Streptococcus forekom i høye relative mengder i både cytobrush-prøvene og vaginalsvaber, og Escherichia-Shigella ble detektert hovedsakelig i vaginalsvabere. Cytobrush-prøvene og vaginalsvabrene hadde lignende taksonomisk sammensetning, hvilket indikerer at det kan være tilstrekkelig å samle en vaginalsvaber for å bestemme overfladisk uterin mikrobiota ved brunst. Et interessant resultat fra studien viste også at Fusobacteriota, som er assosiert med utvikling av metritt og purulent vaginal utflod, og et vanlig funn i uterin mikrobiota hos andre raser, ikke ble funnet i noen av prøvetypene i vår studie. Biopsiprøvene var kvalitativt forskjellige og hadde en mer jevn fordeling av de forskjellige taxa, sammenlignet med cytobrush-prøvene og vaginalsvabrene. Vi spekulerer på om mikrobiota fra dyp endometrium kan være assosiert med sykdommer og tilstand i uterus selv i de tilfeller hvor man ikke ser en slik korrelasjon med mikrobiota fra overfladisk endometrium.
Embryo med opphav fra okser med høy eller lav feltfruktbarhet hadde forskjeller i genekspresjon i gener som er koblet til kolesterolmetabolisme, cytokinsignalisering, regulering av apoptose, embryoets innbinding til uterusveggen ved utvikling av placenta, utvikling av av tight junctions, og regulering av redoks-aktivitet. Disse biokjemiske prosessene er kjente for sin essensielle rolle i embryoutvikling rundt blastocyststadiet og rundt tiden da embryoet fester seg til endometriet.
De samlede resultatene presentert i denne avhandlingen vil være verdifulle for videre forskingen på mekanismer som påvirker fruktbarhet hos melkeku. For NR, er resultatene nyttige ved anbefalinger rundt avl og stell, i tillegg til besetningsutredninger. Dette bidrar til å opprettholde nåværende status hos NR som en rase med høy fruktbarhet, samt videre forbedring av fruktbarheten.Geno S
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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