1,720,975 research outputs found
Discovery of novel prognostic tools to stratify high risk stage II colorectal cancer patients utilising digital pathology
Get PDFColorectal cancer (CRC) patients are stratified by the Tumour, Node and Metastasis
(TNM) staging system for clinical decision making. Additional genomic markers have
a limited utility in some cases where precise targeted therapy may be available. Thus,
classical clinical pathological staging remains the mainstay of the assessment of this
disease. Surgical resection is generally considered curative for Stage II patients,
however 20-30% of these patients experience disease recurrence and disease specific
death. It is imperative to identify these high risk patients in order to assess if further
treatment or detailed follow up could be beneficial to their overall survival. The aim
of the thesis was to categorise Stage II CRC patients into high and low risk of disease
specific death through novel image based analysis algorithms.
Firstly, an image analysis algorithm was developed to quantify and assess the
prognostic value of three histopathological features through immuno-fluorescence:
lymphatic vessel density (LVD), lymphatic vessel invasion (LVI) and tumour budding
(TB). Image analysis provides the ability to standardise their quantification and
negates observer variability. All three histopathological features were found to be
predictors of CRC specific death within the training set (n=50); TB (HR =5.7; 95%
CI, 2.38-13.8), LVD (HR =5.1; 95% CI, 2.04-12.99) and LVI (HR =9.9; 95% CI, 3.57-
27.98). Only TB (HR=2.49; 95% CI, 1.03-5.99) and LVI (HR =2.46; 95%CI, 1 - 6.05),
however, were significant predictors of disease specific death in the validation set
(n=134). Image analysis was further employed to characterise TB and quantify intra-tumoural
heterogeneity. Tumour subpopulations within CRC tissue sections were
segmented for the quantification of differential biomarker expression associated with
epithelial mesenchymal transition and aggressive disease.
Secondly, a novel histopathological feature ‘Sum Area Large Tumour Bud’ (ALTB)
was identified through immunofluorescence coupled to a novel tissue phenomics
approach. The tissue phenomics approach created a complex phenotypic fingerprint
consisting of multiple parameters extracted from the unbiased segmentation of all
objects within a digitised image. Data mining was employed to identify the significant
parameters within the phenotypic fingerprint. ALTB was found to be a more
significant predictor of disease specific death than LVI or TB in both the training set
(HR = 20.2; 95% CI, 4.6 – 87.9) and the validation set (HR = 4; 95% CI, 1.5 – 11.1).
Finally, ALTB was combined with two parameters, ‘differentiation’ and ‘pT stage’,
which were exported from the original patient pathology report to form an integrative
pathology score. The integrative pathology score was highly significant at predicting
disease specific death within the validation set (HR = 7.5; 95% CI, 3 – 18.5).
In conclusion, image analysis allows the standardised quantification of set
histopathological features and the heterogeneous expression of biomarkers. A novel
image based histopathological feature combined with classical pathology allows the
highly significant stratification of Stage II CRC patients into high and low risk of
disease specific death
p53 death pathways in cisplatin-damaged primary murine colonocytes and a possible role for hedgehog developmental genes in colon carcinogenesis
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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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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