166 research outputs found
Turning Privacy Constraints into Syslog Analysis Advantage
Nowadays, failures in high performance computers (HPC) became the norm rather than the exception [10]. In the near future, the mean time between failures (MTBF) of HPC systems is expected to be too short, and that current failure recovery mechanisms e.g., checkpoint-restart, will no longer be able to recover the systems from failures [1]. Early fail- ure detection is a new class of failure recovery methods that can be beneficial for HPC systems with short MTBF. De- tecting failures in their early stage can reduce their negative effects by preventing their propagation to other parts of the system [3]. The goal of the current work is to contribute to the foun- dation of failure detection techniques via sharing an ongo- ing research with the community. Herein we consider user privacy as the main priority, and then turning the applied constraint for protecting users privacy into an advantage for analyzing the system behavior. We use De-identification, constantification, and hashing to reach this goal. Our ap- proach also contributes to the reproducibility and openness of future research in the field. Via this approach, system ad- ministrators can unwarily share their syslogs with the public domain
Analysis of Node Failures in High Performance Computers Based on System Logs
The growth in size and complexity of HPC systems leads to a rapid increase of their failure rates. In the near future, it is expected that the mean time between failures of HPC systems becomes too short and that current failure recovery mechanisms will no longer be able to recover the systems from failures. Early failure detection is, thus, essential to prevent their destructive effects. Based on measurements of a production system at TU Dresden over an 8-month time period, we study the correlation of node failures in time and space. We infer possible types of correlations and show that in many cases the observed node failures are directly correlated. The significance of such a study is achieving a clearer understanding of correlations between observed node failures and enabling failure detection as early as possible. The results aimed to help system administrators minimize (or prevent) the destructive effects of failures
Lessons learned from spatial and temporal correlation of node failures in high performance computers
In this paper we study the correlation of node failures in time and space. Our study is based on measurements of a production high performance computer over an 8-month time period. We draw possible types of correlations between node failures and show that, in many cases, there are direct correlations between observed node failures. The significance of such a study is twofold: achieving a clearer understanding of correlations between node failures and enabling failure detection as early as possible. The results of this study are aimed at helping the system administrators minimize (or even prevent) the destructive effects of correlated node failures
Reproductive factors and risk of melanoma : a population-based cohort study
Background The association between reproductive factors and risk of cutaneous melanoma (CM) is unclear. We investigated this issue in the Norwegian Women and Cancer cohort study. Objectives To examine the association between the reproductive factors age at menarche, menstrual cycle length, parity, age at first and last birth, menopausal status, breastfeeding duration and length of ovulatory life, and CM risk, overall and by histological subtypes and anatomical site. Methods We followed 165 712 women aged 30-75 years at inclusion from 1991-2007 to the end of 2015. Multivariable Cox regression was used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs). Results The mean age at cohort enrolment was 49 years. During a median follow-up of 18 years, 1347 cases of CM were identified. No reproductive factors were clearly associated with CM risk. When stratifying by histological subtype we observed significant heterogeneity (P = 0 center dot 01) in the effect of length of ovulatory life on the risk of superficial spreading melanoma (HR 1 center dot 02, 95% CI 1 center dot 01-1 center dot 04 per year increase) and nodular melanoma (HR 0 center dot 97, 95% CI 0 center dot 94-1 center dot 01 per year increase). When stratifying by anatomical site, menopausal status (HR 0 center dot 54, 95% CI 0 center dot 31-0 center dot 92, postmenopausal vs. premenopausal) and menstrual cycle length (HR 1 center dot 07, 95% CI 1 center dot 01-1 center dot 13, per day increase) were associated with CM of the trunk, and significant heterogeneity between anatomical sites was observed for menopausal status (P = 0 center dot 04). Conclusions In this large population-based Norwegian cohort study, we did not find convincing evidence of an association between reproductive factors and risk of CM.Peer reviewe
Anthropometric Factors and Cutaneous Melanoma: Prospective Data from the Population-based Janus Cohort
The aim of the present study was to prospectively examine risk of cutaneous melanoma (CM) according to measured anthropometric factors, adjusted for exposure to ultraviolet radiation (UVR), in a large population-based cohort in Norway. The Janus Cohort, including 292,851 Norwegians recruited 1972â2003, was linked to the Cancer Registry of Norway and followed for CM through 2014. Cox regression was used to estimate hazard ratios (HRs) of CM with 95% confidence intervals (CIs). Restricted cubic splines were incorporated into the Cox models to assess possible non-linear relationships. All analyses were adjusted for attained age, indicators of UVR exposure, education, and smoking status. During a mean follow-up of 27 years, 3,000 incident CM cases were identified. In men, CM risk was positively associated with body mass index, body surface area (BSA), height and weight (all ptrends \u3c 0.001), and the exposure-response curves indicated an exponential increase in risk for all anthropometric factors. Weight loss of more than 2 kg in men was associated with a 53% lower risk (HR 0.47, 95% CI: 0.39, 0.57). In women, CM risk increased with increasing BSA (ptrend50.002) and height (ptrend \u3c 0.001). The shape of the height- CM risk curve indicated an exponential increase. Our study suggests that large body size, in general, is a CM risk factor in men, and is the first to report that weight loss may reduce the risk of CM among men
Higher incidence of premenopausal breast cancer in less developed countries; myth or truth?
Background: Fundamental etiologic differences have been suggested to cause earlier onset of breast cancer in less developed countries (LDCs) than in more developed countries (MDCs). We explored this hypothesis using world-wide breast cancer incidence data. Methods: We compared international age-standardized incidence rates (ASR) of pre- (<50 years) and postmenopausal (â„50 years) breast cancers as well as temporal trends in ASRs of pre-and postmenopausal breast cancer among selected countries during 1975â2008. We used joinpoint log-linear regression analysis to estimate annual percent changes (APC) for premenopausal and postmenopausal breast cancer in the northern Europe and in Black and White women population in the US. Results: Premenopausal breast cancers comprised a substantially higher proportion of all incident breast cancers in LDCs (average 47.3%) compared to MDCs (average 18.5%). However, the ASR of premenopausal breast cancer was consistently higher in MDCs (29.4/100,000) than LDCs (12.8/100,000). The ASR of postmenopausal cancer was about five-fold higher in the MDCs (307.6/100,000) than the LDCs (65.4/100,000). The APC of breast cancer in Denmark was substantially higher in postmenopausal (1.33%) than premenopausal cancer (0.98%). Higher incidence of breast cancer among the white than black women in the US was pertained only to the postmenopausal cancer. Conclusion: The substantial and consistent lower age-specific incidence of breast cancer in LDCs than in MDCs contradicts the theory of earlier onset. Demographic differences with fewer old women in LDCs and lower prevalence of risk factors of postmenopausal cancer are the most likely explanation to the lower mean age at diagnosis in these countries
Predictors of sun protection behaviours and sunburn among Australian adolescents
BACKGROUND: Excessive sun exposure and sunburn increase individuals' risk of skin cancer. It is especially important to prevent sunburn in childhood due to the higher relative risk of skin cancer across the life span compared to risk associated with sunburn episodes experienced later in life. This study examined demographic and attitudinal factors associated with engagement in a range of sun protection behaviours (wearing a hat, wearing protective clothing, staying in the shade, and staying indoors during the middle of the day) and the frequency of sunburn among Western Australian adolescents to provide insights of relevance for future sun protection campaigns. METHODS: Cross-sectional telephone surveys were conducted annually with Western Australians between 2005/06 and 2014/15. The results from 4150 adolescents aged 14-17 years were used to conduct a path analysis of factors predicting various sun protection behaviours and sunburn. RESULTS: Significant primary predictors of the sun protection behaviours included in the study were skin type (sun sensitivity), gender, tanning-related attitudes and behaviours, and perceived relevance of public service advertisements that advocate sun protection. Of the four sun protection behaviours investigated, staying in the shade and staying indoors during the middle of the day were associated with a lower frequency of sunburn. CONCLUSION: There is a particular need to target sun protection messages at adolescent males who are less likely to engage in the most effective sun protection behaviours and demonstrate an increased propensity to experience sunburn. The results suggest that such future sun protection messages should include a focus on the importance of staying in the shade or indoors during periods of high UV radiation to increase awareness of the efficacy of these methods of avoiding skin cancer
Circulating insulinâlike growth factor I in relation to melanoma risk in the European prospective investigation into cancer and nutrition
Insulinâlike growth factorâI (IGFâI) regulates cell proliferation and apoptosis, and is thought to play a role in tumour development. Previous prospective studies have shown that higher circulating concentrations of IGFâI are associated with a higher risk of cancers at specific sites, including breast and prostate. No prospective study has examined the association between circulating IGFâI concentrations and melanoma risk. A nested caseâcontrol study of 1,221 melanoma cases and 1,221 controls was performed in the European Prospective Investigation into Cancer and Nutrition cohort, a prospective cohort of 520,000 participants recruited from 10 European countries. Conditional logistic regression was used to estimate odds ratios (ORs) for incident melanoma in relation to circulating IGFâI concentrations, measured by immunoassay. Analyses were conditioned on the matching factors and further adjusted for age at blood collection, education, height, BMI, smoking status, alcohol intake, marital status, physical activity and in women only, use of menopausal hormone therapy. There was no significant association between circulating IGFâI concentration and melanoma risk (OR for highest vs lowest fifth = 0.93 [95% confidence interval [CI]: 0.71 to 1.22]). There was no significant heterogeneity in the association between IGFâI concentrations and melanoma risk when subdivided by gender, age at blood collection, BMI, height, age at diagnosis, time between blood collection and diagnosis, or by anatomical site or histological subtype of the tumour (Pheterogeneityâ„0.078). We found no evidence for an association between circulating concentrations of IGFâI measured in adulthood and the risk of melanoma
Evaluating the effectiveness of abbreviated breast MRI (abMRI) interpretation training for mammogram readers: a multi-centre study assessing diagnostic performance, using an enriched dataset
This is the final version. Available on open access from BMC via the DOI in this recordAvailability of data and materials:
The dataset generated and analysed during the current study is not yet publicly available because it is currently being developed into a publicly shareable format. Instead, it is available from the corresponding author on reasonable request.BACKGROUND: Abbreviated breast MRI (abMRI) is being introduced in breast screening trials and clinical practice, particularly for women with dense breasts. Upscaling abMRI provision requires the workforce of mammogram readers to learn to effectively interpret abMRI. The purpose of this study was to examine the diagnostic accuracy of mammogram readers to interpret abMRI after a single day of standardised small-group training and to compare diagnostic performance of mammogram readers experienced in full-protocol breast MRI (fpMRI) interpretation (Group 1) with that of those without fpMRI interpretation experience (Group 2). METHODS: Mammogram readers were recruited from six NHS Breast Screening Programme sites. Small-group hands-on workstation training was provided, with subsequent prospective, independent, blinded interpretation of an enriched dataset with known outcome. A simplified form of abMRI (first post-contrast subtracted images (FAST MRI), displayed as maximum-intensity projection (MIP) and subtracted slice stack) was used. Per-breast and per-lesion diagnostic accuracy analysis was undertaken, with comparison across groups, and double-reading simulation of a consecutive screening subset. RESULTS: 37 readers (Group 1: 17, Group 2: 20) completed the reading task of 125 scans (250 breasts) (total = 9250 reads). Overall sensitivity was 86% (95% confidence interval (CI) 84-87%; 1776/2072) and specificity 86% (95%CI 85-86%; 6140/7178). Group 1 showed significantly higher sensitivity (843/952; 89%; 95%CI 86-91%) and higher specificity (2957/3298; 90%; 95%CI 89-91%) than Group 2 (sensitivity = 83%; 95%CI 81-85% (933/1120) p < 0.0001; specificity = 82%; 95%CI 81-83% (3183/3880) p < 0.0001). Inter-reader agreement was higher for Group 1 (kappa = 0.73; 95%CI 0.68-0.79) than for Group 2 (kappa = 0.51; 95%CI 0.45-0.56). Specificity improved for Group 2, from the first 55 cases (81%) to the remaining 70 (83%) (p = 0.02) but not for Group 1 (90-89% p = 0.44), whereas sensitivity remained consistent for both Group 1 (88-89%) and Group 2 (83-84%). CONCLUSIONS: Single-day abMRI interpretation training for mammogram readers achieved an overall diagnostic performance within benchmarks published for fpMRI but was insufficient for diagnostic accuracy of mammogram readers new to breast MRI to match that of experienced fpMRI readers. Novice MRI reader performance improved during the reading task, suggesting that additional training could further narrow this performance gap.National Institute for Health Research (NIHR
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