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A computational campaign was carried out at the Department of Astronautical, Electrical and Energy Engineering of Sapienza University of Rome aiming at the assessment of RELAP5-3D© capabilities for subchannel analysis. More specifically, the investigation involved a lead-bismuth-eutectic–cooled wire-spaced fuel pin bundle and compared simulation outcomes with experimental data coming from the NAtural CIrculation Experiment-Upgraded (NACIE-UP) facility, hosted at ENEA Brasimone Research Center. Thermal-hydraulic nodalization of the facility was developed with detailed subchannel modeling of the fuel pin simulator (FPS). Three different methodologies for the subchannel simulation were investigated, increasing step by step the complexity of the thermal-hydraulic model. In the simplest approach, the subchannels were modeled one by one. In addition, mass transfer between them was considered thanks to multiple cross junction components, realizing the hydraulic connection between adjacent subchannels. In this case, mass transfer depends on the pressure gradient and hydraulic resistance only, ignoring the turbulent mixing promoted by the wire-wrapped subassembly. Simulation results were not satisfactory, and an improvement was introduced in the second approach. In this case, several control variables calculate at each time step the energy transfer between adjacent control volumes associated with the turbulent mixing induced by the wires. This energy is transferred using ad hoc heat structures (HSs), where the boundary conditions are calculated by the control variables. The present model highlighted good capabilities in the prediction of the radial temperature distribution within the FPS, considerably reducing disagreement with experimental data. Finally, the influence of radial conduction within the fluid domain was assessed, introducing further HSs. Although this most complex model provided the best estimation of the experimental acquisition, the improvements given by radial conduction were not so relevant to justify the correspondent increase of the computational cost. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate the association between cancer patients' ability to share information about their illness with their social network and attachment style dimensions, alexithymia, and quality of life. We hypothesised that ability to share information about one's cancer with family, friends, and medical teams would be positively associated with quality of life and secure attachment and negatively associated with alexithymia., Methods: Forty-five cancer patients were recruited from the Psycho-oncology Unit of the San Camillo-Forlanini Hospital in Rome. We collected anamnestic data and self-report data on social sharing ability, quality of life, alexithymia, and attachment., Results: Sharing with family (B = 4.66; SE = 1.82; β = .52; SE = 0.20; t(41) = 2.6; P = .0143) was the only predictor of global health status, and attachment security was the only predictor of mean social sharing (B = 0.25; SE = 0.06; β = .63; SE = 0.14; t(41) = 4.4; P < .0001)., Conclusions: Encouraging patients to share information about their experience of cancer may help to improve their quality of life. Attachment security seems to promote social sharing. Psychological assessments of cancer patients should cover both ability to share information about one's cancer with family and attachment security., (Copyright © 2016 John Wiley & Sons, Ltd.)

Background: Aim of the study was to prospectively assess the relation between atrial fibrillation, cognitive impairment, frailty and disability in older patients with chronic heart failure ., Methods: Three hundred thirty-one ambulatory community-living patients aged 70 years and older (mean 78 ± 6; range 70-93; 43% women) in stable conditions and optimized therapy were enrolled in seven heart failure cardiology clinics. Cognitive impairment was defined by a corrected Mini Mental State Examination score less than 24. Gait speed was used as marker of frailty and measured on a 4 m distance at usual pace., Results: Ninety-eight patients (30%) were on atrial fibrillation at enrolment and 20 (6%) had a history of paroxysmal/persistent atrial fibrillation. Patients with atrial fibrillation were more frequently women with severe valvular disease, preserved left ventricular ejection fraction and less frequently on beta-blockers. At multivariable analyses, atrial fibrillation emerged as independently related to cognitive impairment [odds ratio (OR) 1.909 (1.072-3.397); P = 0.028], as well as to reduced gait speed [OR 4.366 (2.104-9.060); P < 0.001]. Furthermore, atrial fibrillation was significantly associated with disability in either basic or instrumental activities of daily living. No differences were found in mortality and morbidity., Conclusion: Among patients with chronic heart failure, those with atrial fibrillation present a high prevalence of frailty, cognitive impairment and disability. The hypothetical mechanisms by which atrial fibrillation and heart failure may affect these conditions are multiple and further studies are warranted. However, screening for these variables in clinical practice is simple and inexpensive and may allow better strategies for intervention in this high-risk population.