1,721,115 research outputs found
The genetics of cognition in Schizophrenia
Full text linkBackground: Cognitive impairment is a well-documented feature of schizophrenia and a major determinant of functional outcomes. Cognitive function may be assessed by measuring mean performance measures on cognitive tasks or by measuring variability in performance across tasks or trials of a task that make up a cognitive test battery. Previous research has demonstrated that both cognitive ability and schizophrenia are highly heritable, and that there is a genetic contribution to cognitive impairment in schizophrenia. However, insights into the genetic determinants of cognitive function in schizophrenia remain limited. The overarching aim of the study is to extend current understanding of cognitive impairment in schizophrenia by using previously under-researched or novel metrics of cognitive performance. First, the significance of the phenotype, within-individual variability (WIV) in cognitive performance, was examined in a South African study of people living with schizophrenia. Second, data from the UK Biobank was used to investigate the common genetic determinants of WIV. Third, genetically informed factors corresponding to broad cognitive abilities were used to explore the overlap between the latent cognitive factors, schizophrenia, and schizophrenia symptom dimensions. Methods: A narrative review of the key literature on the clinical, neural, and genetic correlates of WIV was conducted. Multivariable linear regression analyses were then used to assess the relationship between WIV in cognitive performance and selected demographic and clinical variables in 544 people with schizophrenia and 861 matched controls from a South African case-control study. To explore the common genetic basis of WIV, a genome-wide association study (GWAS) of reaction time variability, a measurement of across-task WIV, was conducted in 404,302 individuals from the UK Biobank, a large population-based cohort. Linkage disequilibrium score regression was used to assess the genetic correlations between reaction time variability and selected neuropsychiatric traits, including schizophrenia. Lastly, Genomic Structural Equation Modelling was applied to cognitive data from the UK Biobank to derive latent factors corresponding to broad dimensions of cognitive function. The overlap between the latent cognitive factors, schizophrenia, and schizophrenia symptom dimensions was explored using a variety of statistical approaches, including bivariate MiXeR, the conjunctional false discovery rate method, and polygenic risk score analysis. Results: On a phenotypic level, increased WIV in performance speed across cognitive tests was significantly associated with a diagnosis of schizophrenia, older age, a lower level of education, and a lower score on the global assessment of functioning scale. The GWAS of reaction time variability yielded 161 genome-wide significant single nucleotide polymorphisms distributed across 7 loci, implicating genes involved in synaptic function and neural development. Reaction time variability showed a significant genetic correlation with several traits, including a positive correlation with schizophrenia. Lastly, three latent factors (visuo-spatial, verbal analytic and decision/reaction time) underlying the genetic correlations between the UK Biobank cognitive tests were identified. There was evidence of substantial polygenic overlap between each cognitive factor and schizophrenia but despite the extensive overlap, most significant loci shared between each latent cognitive factor and schizophrenia showed unique patterns of association with the respective factor. Biological annotation of the shared loci implicated gene-sets related to neurodevelopment and neuronal function. Conclusions: The significant relationship between measurements of WIV in performance speed and schizophrenia as well as global functioning in the disorder supports the use of WIV as a measure of cognitive dysfunction in schizophrenia. This thesis demonstrates that reaction time variability is heritable, has a positive genetic correlation with schizophrenia, and that genes associated with reaction time variability have similar biological functions to those affected in schizophrenia. Lastly, substantial overlap in the common genetic influences of latent cognitive factors and schizophrenia was demonstrated. This research suggests that genes related to neurodevelopment and neuronal function underpin cognitive deficits in schizophrenia
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
- …
