Themes of drawing and digital context: student engagement with theory and practice using the tool of the integrated learning portfolio

This article presents a reflective visual narrative documenting the learning encounters of BA (Hons) Surface Design undergraduates using the Integrated Learning Portfolio (ILP) tool in Year one. Theoretical themes of drawing, digital drawing design practice, and visual design research experientially blended the physical and the virtual learning tools, environments and collaborative culture through this integrated first year route. Parallel theory and practice on specific themes such as ‘drawing lines within the urban landscape’, ‘creating shadow silhouettes’, ‘using the body as a tool for drawing’, and ‘cultivating fortuitous accidents in drawing practice’, created a conceptual space for students to evaluate the future relevance of these drawing experiences within the context of their design programme

Abstractions and Analyses of Grid Games

In this paper, we define various combinatorial games derived from the NQueens Puzzle and scrutinize them, particularly the Knights Game, using combinatorial game theory and graph theory. The major result of the paper is an original method for determining who wins the Knights Game merely from the board\u27s dimensions. We also inspect the Knights Game\u27s structural similarities to the Knight\u27s Tour and the Bishops Game, and provide some historical background and real-world applications of the material

Functional assessment for acute stroke trials: properties, analysis, and application

A measure of treatment effect is needed to assess the utility of any novel intervention in acute stroke. For a potentially disabling condition such as stroke, outcomes of interest should include some measure of functional recovery. There are many functional outcome assessments that can be used after stroke. In this narrative review, we discuss exemplars of assessments that describe impairment, activity, participation, and quality of life. We will consider the psychometric properties of assessment scales in the context of stroke trials, focusing on validity, reliability, responsiveness, and feasibility. We will consider approaches to the analysis of functional outcome measures, including novel statistical approaches. Finally, we will discuss how advances in audiovisual and information technology could further improve outcome assessment in trials

The Inverse Redshift-Space Operator: Reconstructing Cosmological Density and Velocity Fields

We present the linear inverse redshift space operator which maps the galaxy density field derived from redshift surveys from redshift space to real space. Expressions are presented for observers in both the CMBR and Local Group rest frames. We show how these results can be generalised to flux--limited galaxy redshift surveys. These results allow the straightforward reconstruction of real space density and velocity fields without resort to iterative or numerically intensive inverse methods. As a corollary to the inversion of the density in the Local Group rest frame we present an expression for estimating the real space velocity dipole from redshift space, allowing one to estimate the Local Group dipole without full reconstruction of the redshift survey. We test these results on some simple models and find the reconstruction is very accurate. A new spherical harmonic representation of the redshift distortion and its inverse is developed, which simplifies the reconstruction and allows analytic calculation of the properties of the reconstructed redshift survey. We use this representation to analyse the uncertainties in the reconstruction of the density and velocity fields from redshift space, due to only a finite volume being available. Both sampling and shot-noise variance terms are derived and we discuss the limits of reconstruction analysis. We compare the reconstructed velocity field with the true velocity field and show that reconstruction in the Local Group rest frame is preferable, since this eliminates the major source of uncertainty from the dipole mode. These results can be used to transform redshift surveys to real space and may be used as part of a full likelihood analysis to extract cosmological parameters.Comment: 13 pages (Latex), 6 postscript figures included, accepted for publication in MNRA

Use of a 3-item short-form version of the Barthel Index for use in stroke: systematic review and external validation

Background and Purpose—There may be a potential to reduce the number of items assessed in the Barthel Index (BI), and shortened versions of the BI have been described. We sought to collate all existing short-form BI (SF-BI) and perform a comparative validation using clinical trial data. Methods—We performed a systematic review across multidisciplinary electronic databases to find all published SF-BI. Our validation used the VISTA (Virtual International Stroke Trials Archive) resource. We describe concurrent validity (agreement of each SF-BI with BI), convergent and divergent validity (agreement of each SF-BI with other outcome measures available in the data set), predictive validity (association of prognostic factors with SF-BI outcomes), and content validity (item correlation and exploratory factor analyses). Results—From 3546 titles, we found 8 articles describing 6 differing SF-BI. Using acute trial data (n=8852), internal reliability suggested redundancy in BI (Cronbach α, 0.96). Each SF-BI demonstrated a strong correlation with BI, modified Rankin Scale, National Institutes of Health Stroke Scale (all ρ≥0.83; P<0.001). Using rehabilitation trial data (n=332), SF-BI demonstrated modest correlation with quality of life measures Stroke Impact Scale and 5 domain EuroQOL (ρ≥0.50, P<0.001). Prespecified prognostic factors were associated with SF-BI outcomes (all P<0.001). Our factor analysis described a 3 factor structure, and item reduction suggested an optimal 3-item SF-BI comprising bladder control, transfer, and mobility items in keeping with 1 of the 3-item SF-BI previously described in the literature. Conclusions—There is redundancy in the original BI; we have demonstrated internal and external validity of a 3-item SF-BI that should be simple to use

Psychological problems in stroke: prevalence, risk factors, and assessment in the pre-stroke state

Background: The psychological impact of stroke is well recognised as being of clinical importance. Historically, this field has received less attention than the physical consequences of stroke, but work designed to develop our understanding of post-stroke psychology is now well underway. Much of the current research of post-stroke psychology is overly limited however; little attention has been paid to the potential impact of the pre-stroke state on post-stroke psychology. As a consequence, fundamental information in relation to the pre-stroke state is lacking, ranging from the prevalence and relevant risk associations of various psychological and physical conditions, to the validity and optimal use of pre-stroke state assessment methods. The purpose of this thesis is to improve our understanding of the pre-stroke state in relation to these under-researched areas. Method: I conducted a series of studies designed to improve our understanding of the pre-stroke state in the areas of prevalence, risk association, and method of assessment. Specifically, I conducted a diagnostic test accuracy study to evaluate the psychometric properties of two informant questionnaires that can be used to assess pre-stroke cognition: the Informant Questionnaire for Cognitive Decline in the Elderly (IQCODE) and Acquired Dementia 8 (AD8). I conducted a systematic review and meta-analyses to establish pre-stroke depression prevalence and investigate its association with post-stroke depression. Based on the findings of this, I explored the potential use of informant tools for pre-stroke depression assessment by comparing the diagnostic test accuracy of the Stroke Aphasic Depression Questionnaire (SADQ) against the Geriatric Depression Scale (GDS), and the diagnostic test accuracy of the best performing informant questionnaire against that of medical records. I conducted secondary analysis of existing data held in two databases to investigate pre-stroke functioning and pre-stroke frailty. The Anglia Stroke Clinical Network Evaluation Study database was utilised to assess the validity of the pre-stroke modified Rankin Scale (mRS) as a measure of function and explore if reported predictive validity of the tool could be influenced by differences in post-stroke care pathway. The Glasgow Royal Infirmary research database was used to investigate the prevalence of pre-stroke frailty, the validity of a Frailty Index for pre-stroke frailty assessment, and a risk association between pre-stroke frailty and acute post-stroke cognition. Findings: I found that the IQCODE and AD8 are valid tools for assessing pre-stroke cognition. However, when utilised at recommended published cut-points the IQCODE is more specific, while the AD8 is more sensitive to cognitive impairment. There is also potential that application of differing cut-points could improve performance when used in a pre-stroke context. My systematic review and meta-analysis suggested that pre-stroke depression prevalence is around 17% and its presence significantly increases odds of post-stroke depression. In addition, there is evidence that the most commonly used method to assess pre-stroke depression, patient medical records, is likely to lack sensitivity to pre-stroke depression. I explored the use of the SADQ and GDS informant tools for assessment of pre-stroke depression. I found that both tools are valid measures of pre-stroke depression, but the GDS has favourable diagnostic test accuracy properties in comparison to the SADQ; comparative test accuracy performance with medical records is inconclusive, but seems to favour the GDS. Pre-stroke mRS evaluation suggests it has moderate validity as a measure of pre-stroke functioning and has predictive validity that could not be accounted for by differences in care pathway. Pre-stroke frailty prevalence is around 28%, rising to ~80% if the pre-frailty state is considered, and the Frailty Index is a valid measure of pre-stroke frailty that can be completed in almost all stroke patients. Pre-stroke frailty also has an association with lower acute post-stroke cognition that is independent of other established risk factors. Conclusions: In conclusion these findings develop our overall understanding of the pre-stroke state. The IQCODE and AD8 are both valid tools for assessment of pre-stroke cognition; however, they demonstrate contrasting strengths when employed at their recommended cut-points and these cut-points may not be the most optimal when these tools are utilised for pre-stroke assessment. Pre-stroke depression appears prevalent, existing in around one in six stroke patients, and it increases the odds of patients experiencing post-stroke depression. It is possible that informant assessment for detection of pre-stroke depression can outperform patient medical records and the GDS appears to outperform the SADQ in the pre-stroke context; however further work is required to confirm this. The pre-stroke mRS is a valid measure of function but has only moderate validity overall and may not be ideally suited to assessment of function in a pre-stroke context. Pre-stroke frailty may exist in around one quarter of stroke patients, and utilisation of a Frailty index approach appears to be valid. The presence of pre-stroke frailty may also contribute to the poor cognitive performance often observed in patients following acute stroke based on an independent association with lower cognitive performance; hence identification of pre-stroke frailty could be of importance to our understanding of post-stroke psychology

Turbulence Chemistry Interaction via Eddy Dissipation Model for Scramjet Analysis and Design

This paper considers the Eddy Dissipation Model to address the combustion process inside scramjet engines designed to operate at high flight Mach numbers. The aim is to demonstrate the most appropriate use of the model for design purposes. To this end, two hydrogen-fueled experimental scramjet configurations with different fuel injection approaches are studied numerically. In the case of parallel fuel injection, it is demonstrated that relying on estimates of ignition delay from a one-dimensional kinetics program can greatly improve the use of the EDM. In the second case, the transverse injection of hydrogen resulted in an overall good agreement of the model with experimental pressure traces except in the vicinity of the injection location. Overall, the EDM appears to be a suitable tool for scramjet combustor design incorporating a parallel or transverse fuel injection mechanism

Optical/Near-Infrared Imaging of Infrared-Excess Palomar-Green QSOs

Ground-based high spatial-resolution (FWHM < 0.3-0.8") optical and near-infrared imaging (0.4-2.2um) is presented for a complete sample of optically selected Palomar-Green QSOs with far-infrared excesses at least as great as those of "warm" AGN-like ultraluminous infrared galaxies (L_ir/L_big-blue-bump > 0.46). In all cases, the host galaxies of the QSOs were detected and most have discernable two-dimensional structure. The QSO host galaxies and the QSO nuclei are similar in magnitude at H-band. H-band luminosities of the hosts range from 0.5-7.5 L* with a mean of 2.3 L*, and are consistent with those found in ULIGs. Both the QSO nuclei and the host galaxies have near-infrared excesses, which may be the result of dust associated with the nucleus and of recent dusty star formation in the host. These results suggest that some, but not all, optically-selected QSOs may have evolved from an infrared-active state triggered by the merger of two similarly-sized L* galaxies, in a manner similar to that of the ultraluminous infrared galaxies.Comment: Aastex format, 38 pages, 4 tables, 10 figures. Higher quality figures are available in JPG forma