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The predictive capabilities of blade-resolved unsteady Reynolds averaged Navier-Stokes (URANS) and detached eddy simulation (DES), the most commonly used hybrid RANS/large eddy simulation (LES) model, are assessed for hydrokinetic turbine performance and mean and turbulent flows in the intermediate-wake region, and results for a range of tip-speed ratio encompassing design and off-design conditions are analyzed to understand the wake recovery mechanism. The performance predictions compared within 5% of the experimental data. Both URANS and DES models performed reasonably well for the near wake predictions, where the errors were

Background: Information is needed regarding the complex relationships between long-term functional outcomes and health-related quality of life (HRQoL) in Hirschsprung's Disease (HSCR). We describe longterm outcomes across multiple domains, completing a core outcome set through to adulthood. Methods: HSCR patients operated at a single center over a 35-year period (1978-2013) were studied. Patients completed detailed questionnaires on bowel and urologic function, and HRQOL. Patients with learning disability (LD) were excluded. Outcomes were compared to normative data. Data are reported as median [IQR] or mean (SD). Results: 186 patients (median age 28 [18-32] years; 135 males) completed surveys. Bowel function was reduced (BFS 17 [14-19] vs. 19 [19-20], p < 0.0001;eta(2) = 0.22). Prevalence and severity of fecal soiling and fecal awareness improved with age ( p < 0.05 for both). Urinary incontinence was more frequent than controls, most of all in 13-26y females (65% vs. 31%, p = 0.003). In adults, this correlated independently with constipation symptoms (OR 3.18 [1.4-7.5], p = 0.008). HRQoL outcomes strongly correlated with functional outcome: 42% of children demonstrated clinically significant reductions in overall PedsQL score, and poor bowel outcome was strongly associated with impaired QOL (B = 22.7 [12.7- 32.7], p < 0.001). In adults, GIQLI scores were more often impacted in patients with extended segment disease. SF-36 scores were reduced relative to population level data in most domains, with large effect sizes noted for females in General Health (g = 1.19) and Social Wellbeing (g = 0.8). Conclusion: Functional impairment is common after pull-through, but bowel function improves with age. Clustering of poor functional outcomes across multiple domains identifies a need for early recognition and long-term support for these patients. (C) 2021 Elsevier Inc. All rights reserved.

The solution to many engineering problems is obtained through the combination of analytical, computational and experimental methods. In many cases, cost or size constraints limit testing of full-scale articles. Similitude allows observations made in the laboratory to be used to extrapolate the behavior to full-scale system by establishing relationships between the results obtained in a scaled experiment and those anticipated for the full-scale prototype. This paper describes the application of the Buckingham Pi theorem to develop a set of non-dimensional parameters that are appropriate for describing the problem of a distributed load applied to the rostrum of the paddlefish. This problem is of interest because previous research has demonstrated that the rostrum is a very efficient structural system. The ultimate goal is to estimate the response of a complex, bio-inspired structure based on the rostrum to blast load. The derived similitude laws are verified through a series of numerical experiments having a maximum error of 3.39%.

This study describes functional and health-related quality of life (HRQoL) outcomes in patients with Hirschsprung’s disease (HSCR) with associated learning disability or neurodevelopmental delay (LD), completing a core outcome set for HSCR. This was a cross-sectional study from a tertiary pediatric surgery center. Patients treated between 1977 and 2013 were prospectively contacted to complete an outcomes survey. Children under 12 and older patients with LD were assisted to complete these by a proxy. Bowel and urologic function were assessed (Rintala’s BFS and modified DanPSS) along with HRQoL (PedsQL/GIQLI/SF-36). Thirty-two patients with LD were compared to 186 patients with normal cognition. Patients with LD had 76% survival over the follow-up period, compared to 99% in the remainder of the cohort. Poor functional outcomes were common in the patients with LD, considerably higher than cognitively normal patients: with weekly issues withholding stool, soiling and fecal accidents in over half of patients surveyed (44–60%), and urinary incontinence in 46%. Use of permanent stoma was significantly higher (22% vs. 4%; p = 0.001). HRQoL was worse in domains of physical functioning in adults and children but not for social or emotional domains in adults. Subgroup analysis of patients with Down syndrome suggested similar functional results but better QoL. Multivariate analysis demonstrated a dramatically higher incidence of poor continence outcomes in patients with LD (adjusted OR 9.6 [4.0–23]).Conclusions: We provide LD-specific outcomes showing inferior function but similar HRQoL to other patients with HSCR, this is much needed in the counselling of families of these children. What is Known:• Hirschsprung’s disease is commonly associated with syndromes or other anomalies with resultant cognitive impairments.• The outcomes for these patients specifically have been poorly described in the literature. What is New:• Objective functional and quality of life surveys demonstrate significant differences from patients without cognitive impairment.• Patients with learning disability Patients with associated LD were almost ten times more likely to have an associated poor functional outcome, with very little impact on proxy-reported quality of life.

The objective of this review was to assess the evidence on relaxation training for management of paediatric headaches. Our methodology was a rapid review of English-language peer reviewed published literature focused on studies evaluating relaxation training as a primary or adjunct management option for headache in a paediatric population (0 to 18 years of age). Seven studies involving 571 children were included in the review. The quality of evidence was very low using GRADE criteria. Headache frequency, duration, and intensity were the primary outcomes in the included studies. Results for the effects of relaxation training for paediatric headache are inconsistent. Four of the seven studies reported decreased headache frequency, two of the five studies reported decreased headache duration, and two of the six studies reported decreased headache intensity following relaxation training. No adverse events were reported. The current state of the evidence for relaxation training for management of paediatric headache is both inconsistent and of very low quality. High-quality research evaluating the effects of relaxation training for paediatric headaches is required to advance the field.

Bio-structures have been optimized by nature to possess remarkable resiliency and strength yet retain a light-weight composition. The hierarchical geometrical arrangements that are prevalent in bio-structures, coupled with heterogeneous constituents, present uncertainty as to what dictates the structural response. Although computational mechanics experiments give an overall distribution of stresses in the structural system, the underlying details of the stress flow patterns in the structure are hard to identify. This paper discusses the development of software that integrates the results from computational mechanics experiments with advanced mathematical algorithms to capture the stress distribution in a bio-structure subjected to an external load. A fundamental issue addressed in this work is the procedure used to prepare data in appropriate format for the seamless transition from finite element binary database files to an abstract mathematical domain. The robust, platform-independent procedure developed for this transdisciplinary strategy efficiently handles the large datasets produced by the high performance computational mechanics experiments.

Objectives The challenges of bioscience courses such as anatomy and physiology in nursing education are well documented. Virtual reality has recently become accessible and may support student engagement. The purpose of this project was to describe students’ engagement and experiences with virtual reality in a first-year nursing course on anatomy, physiology, and health assessment. Methods We used a cross-sectional design and collected both quantitative and qualitative data. The Exploratory Learning Model guided our work. Results Students perceived their engagement to be higher in virtual reality compared to other teaching methods. Their experiences were positive with students reporting that they found it easy to use, it helped their learning, and they recommended more of it. Conclusions Virtual reality is an accessible tool for supporting student engagement. The Exploratory Learning Model is a useful conceptualization for integrating virtual reality into a course. Future research on the relationship between virtual reality and learning achievements is warranted.

In this paper, we revisit the Lagrangian accumulation process that aggregates the local attribute information along integral curves for vector field visualization. Similar to the previous work, we adopt the notation of the Lagrangian accumulation field or A field for the representation of the accumulation results. In contrast to the previous work, we provide a more in-depth discussion on the properties of A fields and the meaning of the patterns exhibiting in A fields. In particular, we revisit the discontinuity in the A fields and provide a thorough explanation of its relation to the flow structure and the additional information about the flow that it may reveal. In addition, other remaining questions about the A field, such as its sensitivity to the selection of integration time, are also addressed. Based on these new insights, we demonstrate a number of enhanced flow visualizations aided by the accumulation framework and the A fields, including a new A field guided ribbon placement, an A field guided stream surface seeding and the visualization of particle-based flow data. To further demonstrate the generality of the accumulation framework, we extend it to the non-integral geometric curves (i.e., streak lines), which enable us to reveal information about the flow behavior other than those revealed by the integral curves. Finally, we introduce the Eulerian accumulation, which can reveal different flow behaviors than those revealed by Lagrangian accumulation. In summary, we believe that Lagrangian accumulation and the resulting A fields offer a valuable means to investigate flow behavior complementary to the current state-of-the-art techniques.

BACKGROUND & PURPOSE Personal support workers, licensed practical nurses, and registered nurses are the primary care providers in long-term care. Research reporting on how these professions collaborate in long-term is limited. Understanding how collaboration occurs in long-term care may support and improve the care of residents. The purpose of this paper is to describe how personal support workers, licensed practical nurses, and registered nurses enact interprofessional collaboration in long-term care. RESEARCH DESIGN & METHODS A qualitative descriptive study using individual interviews with personal support workers, licensed practical nurses, and registered nurses working in long-term care (n = 13) was conducted. Data was categorized according to competencies from the Canadian Interprofessional Health Collaborative, National Interprofessional Competency Framework and then themes were identified to describe how collaboration is enacted. FINDINGS Analysis revealed that collaboration occurs according to five competencies (interprofessional communication, collaborative leadership, role clarification, team functioning, and patient-centred care). Four themes are presented: chain of command communication, leadership based on resident condition, (mis)understanding of roles, and respect within team functioning. These themes are presented because they are organizational aspects of collaboration as opposed to individual attributes and are, therefore, more helpful for those charged with supporting or improving collaboration within an organization. CONCLUSION Personal support workers, licensed practical nurses, and registered nurses naturally enact interprofessional collaboration is a manner that closely aligns with the Canadian Interprofessional Health Collaborative, National Interprofessional Competency Framework. Strategies to support and improve collaboration in long-term care should align with these competencies and take into account the nuances between personal support workers, licensed practical nurses, and registered nurses.

The authors explore multi-domain outcomes in a cross-sectional cohort study of patients with Hirschsprung's Disease. They identify hitherto unrecognised issues affecting sexual function and fertility specifically in female patients.

This paper presents a mesh generation strategy that facilitates the numerical simulation of ice accretion on realistic aircraft configurations by automating the deformation of surface and volume meshes in response to the evolving ice shape. The discrete surface evolution algorithm is based on a face-offsetting strategy that uses an eigenvalue decomposition to determine 1) the nodal offset direction and 2) a null space in which the quality of the surface mesh is improved via point redistribution. A fast algebraic technique is then used to propagate the computed surface deformations into the surrounding volume mesh. Due to inherent limitations in the icing model employed here, there is no intent to present a tool to predict three-dimensional ice accretions but, instead, to demonstrate a meshing strategy for surface evolution and mesh deformation that is appropriate for aircraft icing applications. In this context, sample results are presented for a complex glaze-ice accretion on a rectangular-planform wing ...

This paper documents the predictive capability of rotating blade-resolved unsteady Reynolds averaged Navier-Stokes (URANS) and Improved Delayed Detached Eddy Simulation (IDDES) computations for tidal stream turbine performance and intermediate wake characteristics. Ansys/Fluent and OpenFOAM simulations are performed using mixed-cell, unstructured grids consisting of up to 11 million cells. The thrust, power and intermediate wake predictions compare reasonably well within 10% of the experimental data. For the wake predictions, OpenFOAM performs better than Ansys/Fluent, and IDDES better than URANS when the resolved turbulence is triggered. The primary limitation of the simulations is under prediction of the wake diffusion towards the turbine axis, which in return is related to the prediction of turbulence in the tip-vortex shear layer. The shear-layer involves anisotropic turbulent structures, thus, hybrid RANS/LES models, such as IDDES, are preferred over URANS. Unfortunately, IDDES fails to accurately predict the resolved turbulence in the near-wake region due to the modeled stress depletion issue.

Detailed blast propagation and evolution through multiple structures representing an urban environment were simulated using the code Loci/BLAST, which employs an overset meshing strategy. The use of overset meshes simplifies mesh generation by allowing meshes for individual component geometries to be generated independently. Detailed blast propagation and evolution through multiple structures, wave reflection and interaction between structures, and blast loadings on structures were simulated and analyzed. Predicted results showed good agreement with experimental data generated by the US Army Engineer Research and Development Center. Loci/BLAST results were also found to compare favorably to simulations obtained using the Second-Order Hydrodynamic Automatic Mesh Refinement Code (SHAMRC). The results obtained demonstrated that blast reflections in an urban setting significantly increased the blast loads on adjacent buildings. Correlations of computational results with experimental data yielded valuable insights into the physics of blast propagation, reflection, and interaction under an urban setting and verified the use of Loci/BLAST as a viable tool for urban blast analysis.

We propose a segmentation method for vector fields that employs the accumulated geometric and physical attributes along integral curves to classify their behavior. In particular, we assign to a given spatio-temporal position the attribute value associated with the integral curve initiated at that point. With this attribute information, our segmentation strategy first performs a region classification. Then, connected components are constructed from the derived classification to obtain an initial segmentation. After merging and filtering small segments, we extract and refine the boundaries of the segments. Because points that are correlated by the same integral curve have the same or similar attribute values, the proposed segmentation method naturally generates segments whose boundaries are better aligned with the flow direction. Therefore, additional processing is not required to generate other geometric descriptors within the segmented regions to illustrate the flow behaviors. We apply our method to a number of synthetic and CFD simulation data sets and compare their results with existing methods to demonstrate its effectiveness.

A key design factor impacting the use of electrical power to drive aircraft systems and subsystems is energy efficiency. With the design of an all-electric, hybrid ice protection system, energy consumption can be reduced to a large extent. The hybridization is achieved through an intentional partitioning of the ice at the stagnation line by melting via surface heating and ice shedding in the unheated regions of the airfoil surface via an electromechanical deicing system based on piezoelectric multilayer actuators. To further reduce energy consumption, the adhesion forces between the ice and the airfoil surface can be reduced using an ultrasmooth, nanostructured surface with water- and ice-repellent properties that encourages ice shedding. Experimental investigations, performed in a laboratory-scale icing wind tunnel for a small-scale configuration, reveal that the hybrid approach for ice protection reliably sheds the ice accreted on the airfoil surface. Compared with an all-thermoelectric system for ice p...

A 54-year-old gentleman presented with pulmonary oedema secondary to anterolateral papillary muscle (PPM) rupture and acute mitral regurgitation subsequent to myocardial ischaemia (MI). Angiography revealed complete occlusion of the first obtuse marginal (OM1) branch of the circumflex coronary artery and a 70% occlusion of the left anterior descending (LAD) coronary artery. Operatively, unusual anatomy was noted; an accessory head was attached superiorly to the anterior lateral PPM. This gave rise to chordae that were subsequently attached to the posterior second (P2) scallop. Additionally, the P2 scallop was deficient in chordae from the posteromedial PPM, thus, loss of this accessory head led to severe mitral regurgitation. We review the PPM anatomy and pathological context of PPM rupture and ischaemic mitral regurgitation.