617 research outputs found

    Assessment of deep inspiration breath hold (DIBH) amplitude and reduction in cardiac dose in left breast cancer patients

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    Introduction The primary aim of this study was to examine the impact of deep inspiration breath-hold (DIBH) amplitude on subsequent mean heart dose and V30 during radiotherapy. The secondary aim was to investigate if patient age influenced DIBH amplitude. Method A retrospective study of 30 patients with left-sided breast cancer was completed. Patient were randomly selected from the total number of patients dual scanned in free breathing (FB) and DIBH over a 2-year period. Plans were retrospectively virtually simulated and statistical analysis performed. Results All patients achieved decreased V30 and mean cardiac dose using DIBH. A positive correlation was found between DIBH amplitude and cardiac V30 dose reduction (p=0.007, R=0.48). Ratio of amplitude increase from FB to DIBH and cardiac V30 reduction was positively correlated and statistically significant (p=0.04, R=0.38); Ratio of amplitude increase of at least 15 times FB achieved 100% V30 dose reduction, however this was also achieved with ratio increase as low as 6.25 times FB. A statistically significant positive correlation was identified between DIBH amplitude and mean cardiac dose reduction (p=0.003, R=0.523). No correlation was found between patient age and amplitude ratio increase (p=0.602, R=-0.099) Conclusion A 100% reduction in cardiac V30 can be achieved with a DIBH amplitude increase of 15 times FB. A full reduction can also be achieved at much lower levels (6.25 times FB in current study); however there appears to be no pre-determining patient factors to identify this. DIBH amplitudes of 1cm-4cm reduce cardiac mean dose by at least 50%

    Popular critiques of consultancy and a politics of management learning?

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    In this short article, I argue that popular business discourse on the role of management consultancy in the promotion and translation of management ideas is often critical, informed by more or less implicit ethical and political concerns with employee security, equity, openness and the transparency and legitimacy of responsibility. These concerns are, in part, ‘sayable’ because their object is seen as a scapegoat for management. Nevertheless, combined with the popular form of their expression, they can support and legitimize critical studies of management learning, a discipline which otherwise has become overly concerned with processual and situational phenomena at the expense of broader political dynamics and of the content and consequences of management and management knowledg

    Objectively measured physical activity and fat mass in a large cohort of children

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    Background Previous studies have been unable to characterise the association between physical activity and obesity, possibly because most relied on inaccurate measures of physical activity and obesity. Methods and Findings We carried out a cross sectional analysis on 5,500 12-year-old children enrolled in the Avon Longitudinal Study of Parents and Children. Total physical activity and minutes of moderate and vigorous physical activity (MVPA) were measured using the Actigraph accelerometer. Fat mass and obesity (defined as the top decile of fat mass) were measured using the Lunar Prodigy dual x-ray emission absorptiometry scanner. We found strong negative associations between MVPA and fat mass that were unaltered after adjustment for total physical activity. We found a strong negative dose-response association between MVPA and obesity. The odds ratio for obesity in adjusted models between top and the bottom quintiles of minutes of MVPA was 0.03 (95% confidence interval [CI] 0.01-0.13, p-value for trend < 0.0001) in boys and 0.36 (95% CI 0.17-0.74, p-value for trend = 0.006) in girls. Conclusions We demonstrated a strong graded inverse association between physical activity and obesity that was stronger in boys. Our data suggest that higher intensity physical activity may be more important than total activity

    Give us a game : evaluating the opportunities that exist for English footballers to play in the English Premier League

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    The purpose of this study was to provide a detailed, large-scale retrospective analysis of the number of English footballers that have been developed to play in the English Premier League (EPL) over twenty seasons. Unlike previous research, we examined appearance data as opposed to percentage of squad data enabling a more accurate representation of English players appearing in the EPL. The findings revealed a steady decline in the number and proportion of appearances made by English players in the EPL throughout the twenty season period. However, the results also indicated that the rate of decline had abated since the inception of UEFA's home-grown rule. The results support the view that opportunities for indigenous players have diminished since the EPL's inception. Given the short-term, results-focused culture that prevails in the EPL, this would appear to present a major challenge for governing bodies, particularly those working in elite player development. Discussion surrounding how these challenges might be met is presented

    Experimental and Monte Carlo evaluation of Eclipse treatment planning system for lung dose calculations

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    BackgroundIn this study the accuracy of a pencil beam based treatment planning system (TPS) was evaluated for lung dose calculations by comparison with measurement and the Monte Carlo (MC) method.AimIn the current study we assessed the performance of the Eclipse treatment planning system in the thorax region by ionization chamber measurements and Monte Carlo calculations. We examined two analytic methods: modified Batho (MB) and equivalent tissue-air ratio “ETAR” methods for thorax region irradiations. For Monte Carlo calculations in the thorax phantom, we modelled a Varian Clinac 2100EX linac. After benchmarking our model with water phantom measurements we used this model for thorax phantom calculations.Materials/Methods8 and 15 MV photon beams of Varian 21EX linac were used for irradiations. Using MANP4C Monte Carlo code, the geometry of the linac head was simulated. After commissioning “MC” beam models, lung doses were calculated by the Monte Carlo (MC) method. Irradiation cases were: (1) posterior fields of single lung with field sizes of 4×4 and 10×10cm2 (2) lateral fields of thorax with 4×4 and 10×10cm2 field sizes.ResultsTPS calculations involving ETAR and MB methods were in close agreement with Monte Carlo results and measurements for a 10×10 cm2 field size at both energies. For a field size of 4×4cm2 the maximum differences in local dose between TPS calculations and measurement were +33% (MB) and +28% (ETAR). Also, they ignored lung dose reduction due to lateral electronic equilibrium for small field size. Similar results would be expected for other TPSs implementing these algorithms. MC calculations were in excellent agreement with measurement, showing local differences of no more than 2% for all measured points.ConclusionsOur study findings showed great differences between both analytical methods and measurements for 4×4cm2 field sizes for points in the lung. Our study recommends using the MC method for small-field lung dose calculations

    Investigation of Van Gogh-like 2 mRNA Regulation and Localisation in Response to Nociception in the Brain of Adult Common Carp (Cyprinus carpio)

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    The Van Gogh-like 2 (vangl2) gene is typically associated with planar cell polarity pathways, which is essential for correct orientation of epithelial cells during development. The encoded protein of this gene is a transmembrane protein and is highly conserved through evolution. Van Gogh-like 2 was selected for further study on the basis of consistent regulation after a nociceptive stimulus in adult common carp and rainbow trout in a microarray study. An in situ hybridisation was conducted in the brain of mature common carp (Cyprinus carpio), 1.5 and 3 h after a nociceptive stimulus comprising of an acetic acid injection to the lips of the fish and compared with a saline-injected control. The vangl2 gene was expressed in all brain regions, and particularly intensely in neurons of the telencephalon and in ependymal cells. In the cerebellum, a greater number (P = 0.018) of Purkinje cells expressed vangl2 after nociception (n=7) compared with controls (n = 5). This regulation opens the possibility that vangl2 is involved in nociceptive processing in the adult fish brain and may be a novel target for central nociception in vertebrates

    Intellectual Property and Public Health – A White Paper

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    On October 26, 2012, the University of Akron School of Law’s Center for Intellectual Property and Technology hosted its Sixth Annual IP Scholars Forum. In attendance were thirteen legal scholars with expertise and an interest in IP and public health who met to discuss problems and potential solutions at the intersection of these fields. This report summarizes this discussion by describing the problems raised, areas of agreement and disagreement between the participants, suggestions and solutions made by participants and the subsequent evaluations of these suggestions and solutions. Led by the moderator, participants at the Forum focused generally on three broad questions. First, are there alternatives to either the patent system or specific patent doctrines that can provide or help provide sufficient incentives for health-related innovation? Second, is health information being used proprietarily and if so, is this type of protection appropriate? Third, does IP conflict with other non-IP values that are important in health and how does or can IP law help resolve these conflicts? This report addresses each of these questions in turn
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