121 research outputs found

    Flexible Sigmoidoscopy and CT Colonography Screening: Patients' Experience with and Factors for Undergoing Screening-Insight from the Proteus Colon Trial

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    Purpose To compare the acceptability of computed tomographic (CT) colonography and flexible sigmoidoscopy (FS) screening and the factors predicting CT colonographic screening participation, targeting participants in a randomized screening trial. Materials and Methods Eligible individuals aged 58 years (n = 1984) living in Turin, Italy, were randomly assigned to be invited to screening for colorectal cancer with FS or CT colonography. After individuals who had died or moved away (n = 28) were excluded, 264 of 976 (27.0%) underwent screening with FS and 298 of 980 (30.4%) underwent CT colonography. All attendees and a sample of CT colonography nonattendees (n = 299) were contacted for a telephone interview 3-6 months after invitation for screening, and screening experience and factors affecting participation were investigated. Odds ratios (ORs) were computed by means of multivariable logistic regression. Results For the telephone interviews, 239 of 264 (90.6%) FS attendees, 237 of 298 (79.5%) CT colonography attendees, and 182 of 299 (60.9%) CT colonography nonattendees responded. The percentage of attendees who would recommend the test to friends or relatives was 99.1% among FS and 93.3% among CT colonography attendees. Discomfort associated with bowel preparation was higher among CT colonography than FS attendees (OR, 2.77; 95% confidence interval [CI]: 1.47, 5.24). CT colonography nonattendees were less likely to be men (OR, 0.36; 95% CI: 0.18, 0.71), retired (OR, 0.31; 95% CI: 0.13, 0.75), to report regular physical activity (OR, 0.37; 95% CI: 0.20, 0.70), or to have read the information leaflet (OR, 0.18; 95% CI: 0.08, 0.41). They were more likely to mention screening-related anxiety (mild: OR, 6.30; 95% CI: 2.48, 15.97; moderate or severe: OR, 3.63; 95% CI: 1.87, 7.04), erroneous beliefs about screening (OR, 32.15; 95% CI: 6.26, 165.19), or having undergone a recent fecal occult blood test (OR, 13.69; 95% CI: 3.66, 51.29). Conclusion CT colonography and FS screening are well accepted, but further reducing the discomfort from bowel preparation may increase CT colonography screening acceptability. Negative attitudes, erroneous beliefs about screening, and organizational barriers are limiting screening uptake; all these factors are modifiable and therefore potentially susceptible to interventions. (©) RSNA, 2017 Online supplemental material is available for this article

    Motion Planning and Control for Multi Vehicle Autonomous Racing at High Speeds

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    This paper presents a multi-layer motion planning and control architecture for autonomous racing, capable of avoiding static obstacles, performing active overtakes, and reaching velocities above 75 m/sm/s. The used offline global trajectory generation and the online model predictive controller are highly based on optimization and dynamic models of the vehicle, where the tires and camber effects are represented in an extended version of the basic Pacejka Magic Formula. The proposed single-track model is identified and validated using multi-body motorsport libraries which allow simulating the vehicle dynamics properly, especially useful when real experimental data are missing. The fundamental regularization terms and constraints of the controller are tuned to reduce the rate of change of the inputs while assuring an acceptable velocity and path tracking. The motion planning strategy consists of a Fren\'et-Frame-based planner which considers a forecast of the opponent produced by a Kalman filter. The planner chooses the collision-free path and velocity profile to be tracked on a 3 seconds horizon to realize different goals such as following and overtaking. The proposed solution has been applied on a Dallara AV-21 racecar and tested at oval race tracks achieving lateral accelerations up to 25 m/s2m/s^{2}.Comment: Accepted to the 25th IEEE International Conference on Intelligent Transportation Systems (IEEE ITSC 2022

    Performance of a fully automatic lesion detection system for breast DCE-MRI

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    PURPOSE: To describe and test a new fully automatic lesion detection system for breast DCE-MRI. MATERIALS AND METHODS: Studies were collected from two institutions adopting different DCE-MRI sequences, one with and the other one without fat-saturation. The detection pipeline consists of (i) breast segmentation, to identify breast size and location; (ii) registration, to correct for patient movements; (iii) lesion detection, to extract contrast-enhanced regions using a new normalization technique based on the contrast-uptake of mammary vessels; (iv) false positive (FP) reduction, to exclude contrast-enhanced regions other than lesions. Detection rate (number of system-detected malignant and benign lesions over the total number of lesions) and sensitivity (system-detected malignant lesions over the total number of malignant lesions) were assessed. The number of FPs was also assessed. RESULTS: Forty-eight studies with 12 benign and 53 malignant lesions were evaluated. Median lesion diameter was 6 mm (range, 5-15 mm) for benign and 26 mm (range, 5-75 mm) for malignant lesions. Detection rate was 58/65 (89%; 95% confidence interval [CI] 79%-95%) and sensitivity was 52/53 (98%; 95% CI 90%-99%). Mammary median FPs per breast was 4 (1st-3rd quartiles 3-7.25). CONCLUSION: The system showed promising results on MR datasets obtained from different scanners producing fat-sat or non-fat-sat images with variable temporal and spatial resolution and could potentially be used for early diagnosis and staging of breast cancer to reduce reading time and to improve lesion detection. Further evaluation is needed before it may be used in clinical practice

    Isolation of Listeria monocytogenes in a salami producing plant in Piedmont: use of pulsed field gel electrophoresis to trace contaminations

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    The ability of Listeria monocytogenes to survive in different environments and establish persistent contaminations is an important issue for food producers. This study aimed to assess the environmental contamination level in an Italian salami producing plant and to identify possible sources of contamination using pulsed field gel electrophoresis (PFGE) on L. monocytogenes isolates obtained from environmental (n=54) and meat samples (n=9) collected over 9 months. Detection of L. monocytogenes was performed using the UNI EN ISO 11290-1 procedure and every isolate was characterised with PFGE, using AscI and ApaI restriction enzymes. The environmental detection frequencies were constant both in the first (22%) and the second (27%) visit, thus suggesting the presence of strains adapted to the processing plant. Equipments can represent a reservoir of L. monocytogenes from which it can spread into the whole producing plant. The reservoir was documented by PFGE results which showed several persistent strains. Moreover, PFGE proved the cross-contamination between surfaces and semiprocessed products like pastes, which furthermore have been contaminated by L. monocytogenes in 100% of samples in the first two visits and in 33% in the last visit. This study gave evidence that detection methods and PFGE characterisation can be effective tools to detect possible sources and routes of contamination
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