1,149 research outputs found

    Deep active learning for suggestive segmentation of biomedical image stacks via optimisation of Dice scores and traced boundary length

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    Manual segmentation of stacks of 2D biomedical images (e.g., histology) is a time-consuming task which can be sped up with semi-automated techniques. In this article, we present a suggestive deep active learning framework that seeks to minimise the annotation effort required to achieve a certain level of accuracy when labelling such a stack. The framework suggests, at every iteration, a specific region of interest (ROI) in one of the images for manual delineation. Using a deep segmentation neural network and a mixed cross-entropy loss function, we propose a principled strategy to estimate class probabilities for the whole stack, conditioned on heterogeneous partial segmentations of the 2D images, as well as on weak supervision in the form of image indices that bound each ROI. Using the estimated probabilities, we propose a novel active learning criterion based on predictions for the estimated segmentation performance and delineation effort, measured with average Dice scores and total delineated boundary length, respectively, rather than common surrogates such as entropy. The query strategy suggests the ROI that is expected to maximise the ratio between performance and effort, while considering the adjacency of structures that may have already been labelled – which decrease the length of the boundary to trace. We provide quantitative results on synthetically deformed MRI scans and real histological data, showing that our framework can reduce labelling effort by up to 60–70% without compromising accuracy

    Investigation of glutathione S-transferase zeta and the development of sporadic breast cancer

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    BACKGROUND: Certain genes from the glutathione S-transferase superfamily have been associated with several cancer types. It was the objective of this study to determine whether alleles of the glutathione S-transferase zeta 1 (GSTZ1) gene are associated with the development of sporadic breast cancer. METHODS: DNA samples obtained from a Caucasian population affected by breast cancer and a control population, matched for age and ethnicity, were genotyped for a polymorphism of the GSTZ1 gene. After PCR, alleles were identified by restriction enzyme digestion and results analysed by chi-square and CLUMP analysis. RESULTS: Chi-squared analysis gave a χ(2) value of 4.77 (three degrees of freedom) with P = 0.19, and CLUMP analysis gave a T1 value of 9.02 with P = 0.45 for genotype frequencies and a T1 value of 4.77 with P = 0.19 for allele frequencies. CONCLUSION: Statistical analysis indicates that there is no association of the GSTZ1 variant and hence the gene does not appear to play a significant role in the development of sporadic breast cancer

    Do children with neurological disabilities use more inpatient resources: an observational study.

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    BACKGROUND: Advances in healthcare have improved the survival of children with neurological disabilities (ND). Studies in the US have shown that children with ND use a substantial proportion of resources in children's hospitals, however, little research has been conducted in the UK. We aimed to test the hypothesis that children with neurological disabilities use more inpatient resources than children without neurological disabilities, and to quantify any significant differences in resource use. METHODS: A retrospective observational study was conducted, looking at the number of hospital admissions, total inpatient days and the reason for admissions for paediatric inpatients from January 1st to March 31st 2015. Inpatients were assigned into one of three groups: children without ND, children with one ND, and children with more than one ND. RESULTS: The sample population included 942 inpatients (mean age 6y 6mo). Children with at least one ND accounted for 15.3% of the inpatients, 17.7% of total hospital inpatient admission episodes, and 27.8% of the total inpatients days. Neurological disability had a statistically significant effect on total hospital admissions (p < 0.001). Neurological disability also had a statistically significant effect on total inpatient days (p < 0.001). Neurological disability increased the length of inpatient stay across medicine, specialties, and surgery. CONCLUSIONS: Children with ND had more frequent hospital admission episode and longer inpatient stays. We identified a smaller group within this population, with arguably more complex neurological disabilities, children with more than one ND. This group had the highest number of admissions and longest inpatient stays. More frequent hospital admissions and longer inpatient stays may place children with ND at greater risk of the adverse effects of hospitalisations. We recommend further investigations looking at each the effects of the different categories of ND on inpatient resource use, and repeat of this study at a national level and over a longer period of time

    An appropriate tool for entrepreneurial learning in SMEs? The case of the 20Twenty Leadership Programme

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    The 20Twenty Leadership Programme was developed by Cardiff Metropolitan University as an executive education programme to be delivered within South Wales to small businesses. It is funded by the European Social Fund (ESF) and administered by the Welsh European Funding Office and has the key aim of developing SME’s growth potential via a range of leadership and management skills, including a focus on ‘soft’ skills. The focus of this paper is to place the 20Twenty Leadership Programme within the wider context of entrepreneurship policy and SME training initiatives in particular, and then to examine the rationale and delivery methods of the Programme in relation to these. It also reflects on the Programme’s success (or otherwise) to date where possible. Finally, the paper seeks to suggest fruitful areas of further research both in terms of the 20Twenty Leadership Programme itself, but also with regard to evaluation in relation to other parallel programmes, and to SME training initiatives more generally

    Chronic psychosocial and financial burden accelerates 5-year telomere shortening: findings from the Coronary Artery Risk Development in Young Adults Study.

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    Leukocyte telomere length, a marker of immune system function, is sensitive to exposures such as psychosocial stressors and health-maintaining behaviors. Past research has determined that stress experienced in adulthood is associated with shorter telomere length, but is limited to mostly cross-sectional reports. We test whether repeated reports of chronic psychosocial and financial burden is associated with telomere length change over a 5-year period (years 15 and 20) from 969 participants in the Coronary Artery Risk Development in Young Adults (CARDIA) Study, a longitudinal, population-based cohort, ages 18-30 at time of recruitment in 1985. We further examine whether multisystem resiliency, comprised of social connections, health-maintaining behaviors, and psychological resources, mitigates the effects of repeated&nbsp;burden on telomere attrition over 5 years. Our results indicate that adults with high chronic burden do not show decreased telomere length over the 5-year period. However, these effects do vary by level of resiliency, as regression results revealed a significant interaction between chronic burden and multisystem resiliency. For individuals with high repeated&nbsp;chronic burden and low multisystem resiliency (1 SD below the mean), there was a significant 5-year shortening in telomere length, whereas no significant relationships between chronic burden and attrition were evident for those at moderate and higher levels of resiliency. These effects apply similarly across the three components of resiliency. Results imply that interventions should focus on establishing strong social connections, psychological resources, and health-maintaining behaviors when attempting to ameliorate stress-related decline in telomere length among at-risk individuals

    Anticipated impact of the 2009 Four Corners raid and arrests

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    Archaeological looting on United States federal land has been illegal for over a century. Regardless, the activity has continued in the Four Corners region. This paper discusses how the 1979 Archaeological Resources Protection Act (ARPA) can be viewed as sumptuary law, and within a sumptuary context, subversion can be anticipated. An analysis of 1986 and June 2009 federal raids in the Four Corners will exemplify this point by identifying local discourses found in newspapers both before and after each raid, which demonstrate a sumptuary effect. Ultimately, this paper concludes that looting just adapted, rather than halted, after each federal raid and that understanding this social context of continued local justification and validation of illegal digging is a potential asset for cultural resource protection
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