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PURPOSE: To evaluate the association among suicide behaviors, high-risk behaviors, coping style, and psychological adjustment (i.e., depressive symptomatology, internalizing and externalizing behavior problems) in homeless and non-homeless adolescent males (aged 16 to 19 years). METHODS: Data were obtained from 100 homeless youth accessing an emergency shelter (Ottawa, ON). The comparison group was comprised of 70 youth accessing local community drop-in centers that lived with their parent(s)/guardian(s) and had never stayed in a shelter. Data were analyzed using Chi-square, Student's t-tests, and regression statistics. RESULTS: Relative to non-homeless youth, homeless youth were more likely to report drug, alcohol, and tobacco use, legal problems, academic difficulties, and mental health problems. Homeless youth presented with a higher prevalence of suicidal ideation, past suicide attempts, depressive symptomatology, and internalizing and externalizing behavior problems. Disengagement coping was a predictor of suicidal ideation, past attempts, depressive symptoms and both internalizing and externalizing behavior problems in homeless youth. CONCLUSIONS: Relative to non-homeless youth, findings indicate that homeless youth reported greater use of a disengaging coping style and are at greater risk for high-risk behaviors, past suicide attempts, and clinically elevated levels of depressive symptoms and behavior problems. [ABSTRACT FROM AUTHOR]

Patient-specific finite element (FE) models can assess the impact of mitral valve (MV) repair on the complex MV anatomy and function. However, FE excessive time requirements hamper their use for surgical planning; mass-spring models (MSMs) represent a more approximate approach but can provide almost real-time simulations. On this basis, we implemented MSMs of three healthy MVs from cardiac magnetic resonance (cMR) imaging to simulate the systolic MV closure, including the in vivo papillary muscles and annular kinematics, and the anisotropic and non-linear mechanical response of MV tissues. To test MSM reliability we compared the systolic peak configurations computed by MSMs and FE: mismatches by less than twice the in-plane cMR image resolution were detected over 75% of the leaflets’ surface, independently of the MSM mesh refinement and of the specific MV anatomy. Data on MSMs time-efficiency and data from the comparison of MSMs vs. FE models suggest that MSM could represent a suitable trade-off between almost real-time simulations and reliability when computing MV systolic configuration, with the potential to be used in a clinical setting either as a support to the decisional process or as a virtual training tool. [ABSTRACT FROM AUTHOR]

Bicuspid aortic valve (BAV), i.e. the fusion of two aortic valve cusps, is the most frequent congenital cardiac malformation. Its progression is often characterized by accelerated leaflet calcification and aortic wall dilation. These processes are likely enhanced by altered biomechanical stimuli, including fluid-dynamic wall shear stresses (WSS) acting on both the aortic wall and the aortic valve. Several studies have proposed the exploitation of 4D-flow magnetic resonance imaging sequences to characterize abnormal in vivo WSS in BAV-affected patients, to support prognosis and timing of intervention. However, current methods fail to quantify WSS peak values. On this basis, we developed two new methods for the improved quantification of in vivo WSS acting on the aortic wall based on 4D-flow data. We tested both methods separately and in combination on synthetic datasets obtained by two computational fluid-dynamics (CFD) models of the aorta with healthy and bicuspid aortic valve. Tests highlighted the need for data spatial resolution at least comparable to current clinical guidelines, the low sensitivity of the methods to data noise, and their capability, when used jointly, to compute more realistic peak WSS values as compared to state-of-the-art methods. The integrated application of the two methods on the real 4D-flow data from a preliminary cohort of three healthy volunteers and three BAV-affected patients confirmed these indications. In particular, quantified WSS peak values were one order of magnitude higher than those reported in previous 4D-flow studies, and much closer to those computed by highly time- and space-resolved CFD simulations. [ABSTRACT FROM AUTHOR]