RANS simulations of a 3D sheet-vortex cavitation

On marine propellers, cavitation appearance and development is critical for performance and erosion considerations. Behind a ship, the propeller experiences all kinds of cavitation types, varying from sheet and bubbles to tip vortex cavitation. When a cavitation analysis is required, two methods are available: experimental or numerical. To find the optimum propeller that fits into different configurations and requirements, designers need accurate predictions within reasonable time. The experimental method is typically used at the end of a design process to verify performance. Therefore, quick and accurate numerical predictions are essential at different stages in the design process, to evaluate performance and cavitation patterns. Mathematical methods range from basic panel codes to the more complex ones, derived from the Navier-Stokes equations. Methods like DES and LES require large meshes and small time steps which makes their usability limited. The most practical viscous numerical method available at the moment in industry is Reynolds Average Navier-Stokes (RANS). The current paper will present the results of a RANS simulation of a 2D sheet cavity and a 3D sheet-tip vortex cavitation. Accurate results of these basic simulations are steps towards the end goal, cavitating propeller simulations. In this method the viscous effects are taken into account with aid of a two equation turbulence model, which results in a reasonably fast approach due to reasonably grids requirements. It is concluded that the RANS method can predict complex 3D sheet-vortex cavitation development and shedding. In addition, it is appropriate for industrial use because it achieves reasonably quick and accurate results. As a next step in the research project, the cavitation development on a propeller will be analyzed with this method.http://deepblue.lib.umich.edu/bitstream/2027.42/84248/1/CAV2009-final49.pd

Preoperative CA125 Significantly Improves Risk Stratification in High-Grade Endometrial Cancer

Advanced stage; Endometrial cancer; OutcomeEtapa avançada; Càncer d'endometri; ResultatEtapa avanzada; Cáncer de endometrio; ResultadoPatients with high-grade endometrial carcinoma (EC) have an increased risk of tumor spread and lymph node metastasis (LNM). Preoperative imaging and CA125 can be used in work-up. As data on cancer antigen 125 (CA125) in high-grade EC are limited, we aimed to study primarily the predictive value of CA125, and secondarily the contributive value of computed tomography (CT) for advanced stage and LNM. Patients with high-grade EC (n = 333) and available preoperative CA125 were included retrospectively. The association of CA125 and CT findings with LNM was analyzed by logistic regression. Elevated CA125 ((>35 U/mL), (35.2% (68/193)) was significantly associated with stage III-IV disease (60.3% (41/68)) compared with normal CA125 (20.8% (26/125), [p < 0.001]), and with reduced disease-specific—(DSS) (p < 0.001) and overall survival (OS) (p < 0.001). The overall accuracy of predicting LNM by CT resulted in an area under the curve (AUC) of 0.623 (p < 0.001) independent of CA125. Stratification by CA125 resulted in an AUC of 0.484 (normal), and 0.660 (elevated). In multivariate analysis elevated CA125, non-endometrioid histology, pathological deep myometrial invasion ≥50%, and cervical involvement were significant predictors of LNM, whereas suspected LNM on CT was not. This shows that elevated CA125 is a relevant independent predictor of advanced stage and outcome specifically in high-grade EC

Virtual Reality Aggression Prevention Therapy (VRAPT) versus Waiting List Control for Forensic Psychiatric Inpatients:A Multicenter Randomized Controlled Trial

Many forensic psychiatric inpatients have difficulties regulating aggressive behavior. Evidence of effective aggression treatments is limited. We designed and investigated the effectiveness of a transdiagnostic application of a virtual reality aggression prevention training (VRAPT). In this randomized controlled trial at four Dutch forensic psychiatric centers, 128 inpatients with aggressive behavior were randomly assigned to VRAPT (N = 64) or waiting list control group (N = 64). VRAPT consisted of 16 one-hour individual treatment sessions twice a week. Assessments were done at baseline, post-treatment and at 3-month follow-up. Primary outcome measures were aggressive behavior observed by staff and self-reported aggressive behavior. Analysis was by intention to treat. This trial was registered in the Dutch Trial Register (NTR, TC = 6340). Participants were included between 1 March 2017, and 31 December 2018. Compared to waiting list, VRAPT did not significantly decrease in self-reported or observed aggressive behavior (primary outcomes). Hostility, anger control, and non-planning impulsiveness improved significantly in the VRAPT group compared to the control group at post-treatment. Improvements were not maintained at 3-month follow-up. Results suggest that VRAPT does not decrease aggressive behavior in forensic inpatients. However, there are indications that VRAPT temporarily influences anger control skills, impulsivity and hostility