1,305 research outputs found

    Geometric realizations of generalized algebraic curvature operators

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    We study the 8 natural GL equivariant geometric realization questions for the space of generalized algebraic curvature tensors. All but one of them is solvable; a non-zero projectively flat Ricci antisymmetric generalized algebraic curvature is not geometrically realizable by a projectively flat Ricci antisymmetric torsion free connection

    Applying a User-centred Approach to Interactive Visualization Design

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    Analysing users in their context of work and finding out how and why they use different information resources is essential to provide interactive visualisation systems that match their goals and needs. Designers should actively involve the intended users throughout the whole process. This chapter presents a user-centered approach for the design of interactive visualisation systems. We describe three phases of the iterative visualisation design process: the early envisioning phase, the global specification hase, and the detailed specification phase. The whole design cycle is repeated until some criterion of success is reached. We discuss different techniques for the analysis of users, their tasks and domain. Subsequently, the design of prototypes and evaluation methods in visualisation practice are presented. Finally, we discuss the practical challenges in design and evaluation of collaborative visualisation environments. Our own case studies and those of others are used throughout the whole chapter to illustrate various approaches

    “It’s hard to tell”. The challenges of scoring patients on standardised outcome measures by multidisciplinary teams: a case study of Neurorehabilitation

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    Background Interest is increasing in the application of standardised outcome measures in clinical practice. Measures designed for use in research may not be sufficiently precise to be used in monitoring individual patients. However, little is known about how clinicians and in particular, multidisciplinary teams, score patients using these measures. This paper explores the challenges faced by multidisciplinary teams in allocating scores on standardised outcome measures in clinical practice. Methods Qualitative case study of an inpatient neurorehabilitation team who routinely collected standardised outcome measures on their patients. Data were collected using non participant observation, fieldnotes and tape recordings of 16 multidisciplinary team meetings during which the measures were recited and scored. Eleven clinicians from a range of different professions were also interviewed. Data were analysed used grounded theory techniques. Results We identified a number of instances where scoring the patient was 'problematic'. In 'problematic' scoring, the scores were uncertain and subject to revision and adjustment. They sometimes required negotiation to agree on a shared understanding of concepts to be measured and the guidelines for scoring. Several factors gave rise to this problematic scoring. Team members' knowledge about patients' problems changed over time so that initial scores had to be revised or dismissed, creating an impression of deterioration when none had occurred. Patients had complex problems which could not easily be distinguished from each other and patients themselves varied in their ability to perform tasks over time and across different settings. Team members from different professions worked with patients in different ways and had different perspectives on patients' problems. This was particularly an issue in the scoring of concepts such as anxiety, depression, orientation, social integration and cognitive problems. Conclusion From a psychometric perspective these problems would raise questions about the validity, reliability and responsiveness of the scores. However, from a clinical perspective, such characteristics are an inherent part of clinical judgement and reasoning. It is important to highlight the challenges faced by multidisciplinary teams in scoring patients on standardised outcome measures but it would be unwarranted to conclude that such challenges imply that these measures should not be used in clinical practice for decision making about individual patients. However, our findings do raise some concerns about the use of such measures for performance management

    Treatment sequences and drug costs from diagnosis to death in multiple myeloma

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    Novel therapies for multiple myeloma (MM) have improved patient survival, but their high costs strain healthcare budgets. End-of-life phases of treatment are generally the most expensive, however, these high costs may be less justifiable in the context of a less pronounced clinical benefit. To manage drug expenses effectively, detailed information on end-of-life drug administration and costs are crucial. In this retrospective study, we analysed treatment sequences and drug costs from 96 MM patients in the Netherlands who died between January 2017 and July 2019. Patients received up to 16 lines of therapy (median overall survival: 56.5 months), with average lifetime costs of €209 871 (€3111/month; range: €3942–€776 185) for anti-MM drugs. About 85% of patients received anti-MM treatment in the last 3 months before death, incurring costs of €20 761 (range: €70–€50 122; 10% of total). Half of the patients received anti-MM treatment in the last 14 days, mainly fully oral regimens (66%). End-of-life treatment costs are substantial despite limited survival benefits. The use of expensive treatment options is expected to increase costs further. These data serve as a reference point for future cost studies, and further research is needed to identify factors predicting the efficacy and clinical benefit of continuing end-of-life therapy.</p

    Genome-wide estimation of gender differences in the gene expression of human livers: Statistical design and analysis

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    BACKGROUND: Gender differences in gene expression were estimated in liver samples from 9 males and 9 females. The study tested 31,110 genes for a gender difference using a design that adjusted for sources of variation associated with cDNA arrays, normalization, hybridizations and processing conditions. RESULTS: The genes were split into 2,800 that were clearly expressed (expressed genes) and 28,310 that had expression levels in the background range (not expressed genes). The distribution of p-values from the 'not expressed' group was consistent with no gender differences. The distribution of p-values from the 'expressed' group suggested that 8 % of these genes differed by gender, but the estimated fold-changes (expression in males / expression in females) were small. The largest observed fold-change was 1.55. The 95 % confidence bounds on the estimated fold-changes were less than 1.4 fold for 79.3 %, and few (1.1%) exceed 2-fold. CONCLUSION: Observed gender differences in gene expression were small. When selecting genes with gender differences based upon their p-values, false discovery rates exceed 80 % for any set of genes, essentially making it impossible to identify any specific genes with a gender difference

    A systematic review of the literature on digital transformation: insights and implications for strategy and organizational change

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    In this article we provide a systematic review of the extensive yet diverse and fragmented literature on digital transformation (DT), with the goal of clarifying boundary conditions to investigate the phenomenon from the perspective of organizational change. On the basis of 279 articles, we provide a multi-dimensional framework synthesizing what is known about DT and discern two important thematical patterns: DT is moving firms to malleable organizational designs that enable continuous adaptation, and this move is embedded in and driven by digital business ecosystems. From these two patterns, we derive four perspectives on the phenomenon of DT: technology impact, compartmentalized adaptation, systemic shift and holistic co-evolution. Linking our findings and interpretations to existing work, we find that the nature of DT is only partially covered by conventional frameworks on organizational change. On the basis of this analysis, we derive a research agenda and provide managerial implications for strategy and organizational change.info:eu-repo/semantics/publishedVersio

    New technologies for 3D realization in Art and Design practice

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    As digital design technologies become ever more widespread, CAD-CAM, virtual and rapid prototyping techniques are increasingly being exploited by creative practitioners working in areas outside the industrial design and engineering contexts in which these technologies are currently predominantly employed. This review paper aims to critically examine work by artists, craft practitioners, and designer-makers who creatively engage with these new and rapidly emerging technologies and, by doing so, extend their own practice and push at the boundaries of art and design disciplines. Historic precedents for new 3D technologies in the fine and applied arts are identified, and writing by Heidegger, Baudrillard, and Virilio informs the critical review of work by art and design practitioners in sculpture, metalwork, jewellery, and ceramics. The discussion reflects on relationships between art and technology and physical and virtual making, and concludes by pointing to the possibility of new “hybrid” forms of practice which bridge the gap between physical and virtual design worlds. The paper closes by suggesting that the notion of “truth to materials” in the arts and crafts might now be extended to one of “truth to virtual materials”, as practitioners creatively negotiate relationships between digital cause and physical effect
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