1,720,983 research outputs found
Enrichment and characterisation of the skeletal stem cell population
No full textThroughout the world, the average population age is increasing and, in many areas, nearly a quarter of the population will be over the age of 65 within the next 15 years, 40% of the total NHS budget is spent on people over the age of 65. The UK spends to £13 billion on musculoskeletal treatments, a cost which will increase as the population over 65 also increases. Skeletal stem cells are a rare cell population within the bone marrow, which facilitate bone repair and homeostasis. With no identified markers capable of isolating skeletal stem cells, characterisation, understanding, and subsequent use is limited. Understanding these cells within the skeletal system may help us understand disease states, the causes and, importantly, offer therapeutic solutions.This thesis approached the study of skeletal stem cells from two alternative angles. The first, a marker discovery direction using aptamers (synthetic binding ligands, normally nucleic acid based) to identify and exploit potential skeletal stem cell-specific markers. The second approach using current enrichment techniques and the application of Drop-Seq to characterise the enriched cell gene expression profiles at a single cell level. Aptamer selection was first applied against a bonederived cell line, SAOS-2, to ensure a robust methodology was established before the use of precious primary human skeletal tissue. The SAOS-2 selection proved successful, providing ten aptamers which preferentially bound to the SAOS-2 cells over a counter selection target of the Raji cell line. Unfortunately, when carrying out the same aptamer selection method using bone marrow and foetal femur samples unwanted amplification took place within all the attempted selections, resulting in failure of selection. This was narrowed down to amplification products from the cell that was not detected in QC steps.The use of enrichment markers provided a population (STRO-1BRIGHT+ CD146+) highly enriched for Colony Forming Units - Fibroblastic (CFU-F) capacity. This population was too small for use with Drop-Seq. STRO-1+ CD146+ cells were therefore analysed instead. The analysis highlighted four main cell types within the population, monocytes, lymphocytes, erythrocyte progenitors and CXC chemokine ligand (CXCL) 12-abundant reticular (CAR) cells.The failure of the aptamer selection against the primary cells presented a setback to the characterisation of the skeletal stem cells. However, with a redesign of the primers and aptamer pool, this methodology should prove fruitful. The identification of the CAR cells is highly intriguing as these cells are studied within the haematopoietic stem cell field, as the CAR cells act as regulatory cells of the haematopoietic stem cells. The CAR cells have been shown to be multipotent, differentiating into adipocytes, chondrocytes and osteocytes, and are a rare population. These characteristics are shared with the characteristics attributed to the skeletal stem cell, and therefore the identification of the CAR cells from a population enriched for the skeletal stem cells suggests a relationship between these cells, whether the SSCs are the CAR cells or are closely related is unclear at this point, with further protein localisation studies this may be elucidated
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
Hans Urs von Balthasar's Theology of the Holy Saturday: Christological and Eschatological Aspects of "Descenoit ad infera".
No full textThis thesis discusses Hans Urs von Balthasar"s theology of Holy Saturday. In the first part, I provide a short overview of Balthasar"s life and seminal works. I confine myself to those themes of his theology that are important for our profound pre-understanding of his interpretation of Lord"s descent into hell. A thorough look on Balthasar"s Decendit ad infera scheme opens up into a wider discussion, both from contemporary theologians, and from the author of the thesis himself. The debate is contextualized by a closer examination of the history of interpretation of the corresponding article of the Apostles" Creed. The historical synopsis reviews both biblical and patristic sources, and describes its encapsulation in major Christian traditions (Eastern Orthodox, Roman Catholic, Lutheran, and Reformed). Powered by TCPDF (www.tcpdf.org
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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