1,721,290 research outputs found
Blood-based biomarkers in psychiatric diseases
No full textIdentification of blood-based biomarkers for psychiatric disease risk and development has emerged as an important area of translational research in medicine, offering a means to supplement or replace current interview-based methods for psychiatric diagnosis. The aim of this thesis is to assess the utility of genome-wide blood transcriptome profiling for the prediction, diagnosis and treatment of patients with psychiatric diseases. Some parts of this work are of a more methodological nature and geared towards the discovery of blood-based biomarkers and gene networks, while others consider mechanistic and translational implications. Overall, this work contributes to understanding the pathophysiology of major psychiatric diseases and to the development of new biomarkers and treatments. Part I discusses the current transition from interview-based psychiatric diagnostics towards genomic-based interventions (Chapter 1) prior to introducing experimental methodologies (Chapter 2) and statistical approaches (Chapter 3) that may provide favorable translational avenues for blood biomarker discovery in psychiatry. Part II contains four investigations (summarized in Chapter 4) that apply genome-wide transcriptome profiling of patient blood samples in pursuit of blood-based biomarkers and gene networks implicated in posttraumatic stress disorder (Chapter 5), acute psychological stress (Chapter 6), methamphetamine-associated psychosis (Chapter 7) and treatment response in bipolar disorder (Chapter 8). Part III proposes a set of rules or postulates for accelerating the identification of reliable and accurate blood-based biomarkers in patients with psychiatric diseases (Chapter 9
Systematic review of blood transcriptome profiling in neuropsychiatric disorders: guidelines for biomarker discovery
No full textIntroduction: The utility of blood for genome-wide gene expression profiling and biomarker discovery has received much attention in patients diagnosed with major neuropsychiatric disorders. While numerous studies have been conducted, statistical rigor and clarity in terms of blood-based biomarker discovery, validation, and testing are needed.Methods: We conducted a systematic review of the literature to investigate methodological approaches and to assess the value of blood transcriptome profiling in research on mental disorders. We were particularly interested in statistical considerations related to machine learning, gene network analyses, and convergence across different disorders.Results: A total of 108 peripheral blood transcriptome studies across 15 disorders were surveyed: 25 studies used a variety of machine learning techniques to assess putative clinical viability of the candidate biomarkers; 11 leveraged a higher-order systems-level perspective to identify gene module-based biomarkers; and nine performed analyses across two or more neuropsychiatric phenotypes. Notably, ~50% of the surveyed studies included fewer than 50 samples (cases and controls), while ~75% included less than 100.Conclusions: Detailed consideration of statistical analysis in the early stages of experimental planning is critical to ensure blood-based biomarker discovery and validation. Statistical guidelines are presented to enhance implementation and reproducibility of machine learning and gene network analyses across independent studies. Future studies capitalizing on larger sample sizes and emerging next-generation technologies set the stage for moving the field forwards
The Life and Legacy of Andreas Vesalius’s Fabrica and Being an Author in the Renaissance
No full texthttps://rdc.reed.edu/v1/resources/3a0924ec-e225-47dd-932f-0395e2c6c2a5/thumb/128.jpgTo better understand the relationship between the advent of the Gutenberg press and the so-called scientific revolution of the fifteenth and sixteenth centuries, this thesis tracks Andreas Vesalius’s De humani corporis fabrica libri septem’s life, from the author’s inspiration for writing the text through its publication, examining its impact on the field of anatomy and medicine both immediately after its publication and in subsequent centuries to understand the impact a single author and text can have on a field. As he was one of the first generations to grow up with the printing press, Vesalius was able to take advantage of printing and publishing in his early life to establish a name for himself. While studying anatomy, he realized several errors in the works of Galen, prompting the realization that physicians rarely question what they believe to be established anatomical facts. This prompted Vesalius to undertake human cadaveric dissection to empirically observe human anatomy. In the Fabrica, Vesalius shared his findings and corrections and advocated for physicians to question medical authorities by dissecting human cadavers themselves and verify these texts in pursuit of anatomical truth. The Fabrica included several detailed woodcut images showcasing human anatomy that were read in tandem with the text, setting a precedent for all future anatomy texts. The success of the Fabrica immediately changed Vesalius’s life and career as he became an imperial physician to Emperor Charles V. The work was prolifically pirated and plagiarized, contributing to its popularity and impact. After Vesalius’s death, the Fabrica continued to change the field of medicine, prompting an “anatomical renaissance”, inspiring several subsequent texts, and heralding pedagogical changes to how medicine was learned and practiced. Today, historians credit Andreas Vesalius with reviving interest in the field of anatomy, and he is remembered as the founder of modern anatomy, with his Fabrica having successfully changed the world
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
Incoherence in regime complexes: a sentiment analysis of EU-IMF surveillance
Full text linkThe proliferation of international institutions means that states can be subject to multiple, overlapping and potentially incoherent international obligations. The regime complexity literature draws attention to this problem but says little about its character and causes. This article investigates whether and why two key components of the international economic surveillance regime – the International Monetary Fund (IMF) and the European Union (EU) – impose conflicting obligations on the same states. Based on a comparative sentiment analysis of more than 400 surveillance documents and using differences in tone as a proxy for incoherence, our results show that the IMF was more pessimistic about member states’ economic policies before the global financial crisis but less so thereafter. Our results point towards the importance of discretionary authority rather than the distribution of power, with the EU and IMF responding to different rules with differing degrees of intensity, leading to incoherent assessments of member states’ economic policies. \ud
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Keywords: international institutions; EU; IMF; regime complexity; international economic surveillance; sentiment analysi
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
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