2,129 research outputs found

    Independent predictors of breast malignancy in screen-detected microcalcifications: biopsy results in 2545 cases

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    Background: Mammographic microcalcifications are associated with many benign lesions, ductal carcinoma in situ (DCIS) and invasive cancer. Careful assessment criteria are required to minimise benign biopsies while optimising cancer diagnosis. We wished to evaluate the assessment outcomes of microcalcifications biopsied in the setting of population-based breast cancer screening. Methods: Between January 1992 and December 2007, cases biopsied in which microcalcifications were the only imaging abnormality were included. Patient demographics, imaging features and final histology were subjected to statistical analysis to determine independent predictors of malignancy. Results: In all, 2545 lesions, with a mean diameter of 21.8 mm (s.d. 23.8 mm) and observed in patients with a mean age of 57.7 years (s.d. 8.4 years), were included. Using the grading system adopted by the RANZCR, the grade was 3 in 47.7%; 4 in 28.3% and 5 in 24.0%. After assessment, 1220 lesions (47.9%) were malignant (809 DCIS only, 411 DCIS with invasive cancer) and 1325 (52.1%) were non-malignant, including 122 (4.8%) premalignant lesions (lobular carcinoma in situ, atypical lobular hyperplasia and atypical ductal hyperplasia). Only 30.9% of the DCIS was of low grade. Mammographic extent of microcalcifications >15 mm, imaging grade, their pattern of distribution, presence of a palpable mass and detection after the first screening episode showed significant univariate associations with malignancy. On multivariate modeling imaging grade, mammographic extent of microcalcifications >15 mm, palpable mass and screening episode were retained as independent predictors of malignancy. Radiological grade had the largest effect with lesions of grade 4 and 5 being 2.2 and 3.3 times more likely to be malignant, respectively, than grade 3 lesions. Conclusion: The radiological grading scheme used throughout Australia and parts of Europe is validated as a useful system of stratifying microcalcifications into groups with significantly different risks of malignancy. Biopsy assessment of appropriately selected microcalcifications is an effective method of detecting invasive breast cancer and DCIS, particularly of non-low-grade subtypes.G Farshid, T Sullivan, P Downey, P G Gill, and S Pieters

    Using Jungian Personality Types for Teaching Teamwork in a Software Engineering Capstone Course

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    Contains fulltext : 231320.pdf (Publisher’s version ) (Closed access)SIGCSE'2

    Estimating the burden of disease attributable to diabetes in South Africa in 2000

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    Objectives. To estimate the burden of disease attributable to diabetes by sex and age group in South Africa in 2000. Design. The framework adopted for the most recent World Health Organization comparative risk assessment (CRA) methodology was followed. Small community studies used to derive the prevalence of diabetes by population group were weighted proportionately for a national estimate. Populationattributable fractions were calculated and applied to revised burden of disease estimates. Monte Carlo simulation-modelling techniques were used for uncertainty analysis. Setting. South Africa. Subjects. Adults 30 years and older. Outcome measures. Mortality and disability-adjusted life years (DALYs) for ischaemic heart disease (IHD), stroke, hypertensive disease and renal failure. Results. Of South Africans aged ≥ 30 years, 5.5% had diabetes which increased with age. Overall, about 14% of IHD, 10% of stroke, 12% of hypertensive disease and 12% of renal disease burden in adult males and females (30+ years) were attributable to diabetes. Diabetes was estimated to have caused 22 412 (95% uncertainty interval 20 755 - 24 872) or 4.3% (95% uncertainty interval 4.0 - 4.8%) of all deaths in South Africa in 2000. Since most of these occurred in middle or old age, the loss of healthy life years comprises a smaller proportion of the total 258 028 DALYs (95% uncertainty interval 236 856 - 290 849) in South Africa in 2000, accounting for 1.6% (95% uncertainty interval 1.5 - 1.8%) of the total burden. Conclusions. Diabetes is an important direct and indirect cause of burden in South Africa. Primary prevention of the disease through multi-level interventions and improved management at primary health care level are needed

    Exoten in de Nederlandse avifauna: integratie of concurrentie?

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    Environmental Biology - ol

    Cross-talk between signaling pathways leading to defense against pathogens and insects

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    In nature, plants interact with a wide range of organisms, some of which are harmful (e.g. pathogens, herbivorous insects), while others are beneficial (e.g. growth-promoting rhizobacteria, mycorrhizal fungi, and predatory enemies of herbivores). During the evolutionary arms race between plants and their attackers, primary and secondary immune responses evolved to recognize common or highly specialized features of microbial pathogens (Chisholm et al., 2006), resulting in sophisticated mechanisms of defense

    Bluetooth command and control channel

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    Bluetooth is popular technology for short-range communications and is incorporated in mobile devices such as smartphones, tablet computers and laptops. Vulnerabilities associated with Bluetooth technology led to improved security measures surrounding Bluetooth connections. Besides the improvement in security features, Bluetooth technology is still plagued by vulnerability exploits. This paper explores the development of a physical Bluetooth C&C channel, moving beyond previous research that mostly relied on simulations. In order to develop a physical channel, certain requirements must be fulfilled and specific aspects regarding Bluetooth technology must be taken into consideration. To measure performance, the newly designed Bluetooth C&C channel is executed in a controlled environment using the Android operating system as a development platform. The results show that a physical Bluetooth C&C channel is indeed possible and the paper concludes by identifying potential strengths and weaknesses of the new channel.http://www.elsevier.com/locate/cosehb2016Computer Scienc

    Design of a hybrid command and control mobile botnet

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    The increasing popularity and improvement in capabilities offered by smartphones caught the attention of botnet developers. Now the threat of botnets is moving towards the mobile environment. This study presents the design of a hybrid command and control mobile botnet. The hybrid design explores the efficiency of multiple command and control channels against the following objectives: no single point of failure within the topology, low cost for command dissemination, limited network activities and low battery consumption. The objectives are measured with a prototype that is deployed on a small collection of Android-based smartphones. The results indicate that current mobile technology exhibits all the capabilities needed to create a mobile botnet.http://www.jinfowar.comam2017Computer Scienc

    News discourses on distant suffering: A critical discourse analysis of the 2003 SARS outbreak

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    News carries a unique signifying power, a power to represent events in particular ways (Fairclough, 1995). Applying Critical Discourse Analysis and Chouliaraki's theory on the mediation of suffering (2006), this article explores the news representation of the 2003 global SARS outbreak. Following a case-based methodology, we investigate how two Belgian television stations have covered the international outbreak of SARS. By looking into the mediation of four selected discursive moments, underlying discourses of power, hierarchy and compassion were unraveled. The analysis further identified the key role of proximity in international news reporting and supports the claim that Western news media mainly reproduce a Euro-American centered world order. This article argues that news coverage of international crises such as SARS constructs and maintains the socio-cultural difference between 'us' and 'them' as well as articulating global power hierarchies and a division of the world in zones of poverty and prosperity, danger and safety

    Smartphone data evaluation model : identifying authentic smartphone data

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    Ever improving smartphone technology, along with the widespread use of the devices to accomplish daily tasks, leads to the collection of rich sources of smartphone data. Smartphone data are, however, susceptible to change and can be altered intentionally or accidentally by end-users or installed applications. It becomes, therefore, important to establish the authenticity of smartphone data, confirming the data refer to actual events, before submitting the data as potential evidence. This paper focuses on data created by smartphone applications and the techniques that can be used to establish the authenticity of the data. To identify authentic smartphone data, a better understanding of the smartphone, related smartphone applications and the environment in which the smartphone operates are required. From the gathered knowledge and insight, requirements are identified that authentic smartphone data must adhere to. These requirements are captured in a new model to assist digital forensic professionals with the evaluation of smartphone data. Experiments, involving different smartphones, are conducted to determine the practicality of the new evaluation model with the identification of authentic smartphone data. The presented results provide preliminary evidence that the suggested model offers the necessary guidance to identify authentic smartphone data.http://www.elsevier.com/locate/diinhj2019Computer Scienc

    Reference architecture for android applications to support the detection of manipulated evidence

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    Traces found on Android smartphones form a significant part of digital investigations. A key component of these traces is the date and time, often formed as timestamps. These timestamps allow the examiner to relate the traces found on Android smartphones to some real event that took place. This paper performs exploratory experiments that involve the manipulation of timestamps found in SQLite databases on Android smartphones. Based on observations, specific heuristics are identified that may allow for the identification of manipulated timestamps. To overcome the limitations of these heuristics, a new reference architecture for Android applications is also introduced. The reference architecture provides examiners with a better understanding of Android applications as well as the associated digital evidence. The results presented in the paper show that the suggested techniques to establish the authenticity and accuracy of digital evidence are feasible.http://www.saiee.org.za/DirectoryDisplay/DirectoryCMSPages.aspx?name=Publications#id=1588&dirname=ARJ&dirid=337am2017Computer Scienc
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