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This development is further maintained under the following software publication: https://doi.org/10.14278/rodare.767 A solver for multiphase flows based on the incompressible Eulerian multi-field two-fluid model for the OpenFOAM release of The OpenFOAM Foundationfor numerical simulations of multiphase flows with morphology changes and resolved interfaces. Features: morphology adaptive modeling framework for modelling of dispersed and resolved interfaces based on Eulerian multi-field two-fluid model compact interpolation method according to Cubero et al. (Comput Chem Eng, 2014, Vol. 62, 96-107), including virtual mass numerical drag according to Strubelj and Tiselj (Int J Numer Methods Eng, 2011, Vol. 85, 575-590) to describe resolved interfaces in a volume-of-fluid like manner n-phase partial elimination algorithm for momentum equations to resolve strong phase coupling bubble induced turbulence model of Ma et al. (Phys Rev Fluids, 2017, Vol. 2, 034301) turbulent wall functions of Menter according to Rzehak & Kriebitzsch (Int J Multiphase Flow, 2015, Vol. 68, 135–152) free surface turbulence damping for k-ω SST (symmetric and asymmetric damping, Frederix et al., Nucl Eng Des, 2018, Vol. 333, 122-130) dynamic time step adjustment via PID controller selected test cases: a two-dimensional gas bubble, rising in a liquid, which is laden with micro gas bubbles, and a two-dimensional stagnant stratification of water and oil, sharing a large-scale interface a two-dimensional stratified flow based on WENKA experiment (Stäbler, Ph.D. thesis, 2007)

Stratified flows of water and steam can appear in the primary system of a pressurized water reactor during a hypothetical loss-of-coolant accident. Among others, important safety concerns during cold water injection of the emergency core cooling system include the pressurized thermal shock and the possible formation of a condensation induced water hammer. Both mechanisms could cause significant thermal and mechanical stresses on the components of the primary system. Thorough knowledge of turbulent heat and mass transfer processes near the interface is required for safety analyses of both phenomena. Measurements of industrially relevant turbulent two-phase flows tend to be difficult; therefore computational fluid dynamics simulations represent an important additional analytical tool. The main objective of the present research and development is to advance the capabilities of current state-of-the-art modeling tools towards the simulations of two-phase flow phenomena under realistic reactor conditions. In the present paper, the focus is on turbulence modelling near the gas liquid interface in stratified flows. An isothermal stratified counter-current flow of air and water in a rectangular channel is simulated. Computational domain and boundary conditions are based on the flow conditions in the test section of the WENKA experiment [1]. The validation case considers supercritical stratified flow with Froude number of 2.36 and Reynolds number 12000 for water and 27000 for air. The two-fluid modeling approach with interface compression is used to resolve the interface between the two phases. A consistent momentum interpolation numerical scheme is applied, featuring the partial elimination algorithm to handle the strong interphase drag coupling at a resolved interface. The Unsteady Reynolds Averaged Navier-Stokes (URANS) approach is used to describe turbulent two-phase flow. Modelling of turbulence dissipation at the interface requires a special treatment that includes introduction of additional turbulence damping terms into the k-ω Shear Stress Transport (SST) turbulence equations. Simulations, model and source code development are performed with the open source C++ library OpenFOAM. Simulation results are validated with the measured profiles of volume fraction, velocity and turbulent kinetic energy at two streamwise positions in the test section of the WENKA experiment. Results of the mesh sensitivity study are presented. Furthermore, results of a parametric study reveal that an asymmetric damping approach with a lower coefficient on the liquid side of the interface can improve the prediction of turbulent kinetic energy profiles. [1] Stäbler, T., Meyer, L., Schulenberg, T., & Laurien, E. (2006). Turbulence Structures in Horizontal Two-Phase Flows Under Counter-Current Conditions. Proceedings of FEDSM2006 (pp. 61–66). ASME.

Introduction: We report a case of a lost metal platelet from a radiofrequency ablation probe (VAPR VUE Radiofrequency System, Cool Pulse 90, DePuy, Synthes, Switzerland) in the shoulder joint during elective arthroscopic cuff repair. To the best of our knowledge, this kind of an incident during elective arthroscopy has not been described in the literature so far. In addition, we present an algorithm on how to deal with such an incident. Case Report: A 69-year-old woman underwent an arthroscopic subacromial decompression and rotator cuff repair for a torn supraspinatus tendon. While performing the subacromial decompression and after swapping the portals from lateral to posterior, the metal platelet of the electrocautery device got detached from the instrument and lost in the operation field. Several attempts to visualize the lost platelet with the camera failed. Finally, intraoperative fluoroscopic imaging was used to detect the platelet. To confirm the definitive whereabouts of the platelet, two spinal needles were positioned perpendicular to another under x-ray control, both pointing at the missing platelet. After determining the exact location, the platelet could finally be visualized with the camera and removed. Due to this incident, the operation time was extended extensively, and the patient as well as the theatre team was exposed to an unnecessary amount of radiation. Conclusion: This report indicates that an extraordinary incident such as the detachment of a component of the arthroscopic equipment during surgery is possible and should be kept in mind by the surgeon. Therefore, we believe that it is essential to perform a test of integrity at least at the end of every operation. In addition, we are presenting an algorithm on how to deal with the situation of a lost foreign body during arthroscopy, which can be applied to any joint.

Industrial applications feature a huge variety of different flow patterns, such as bubbly flow, slug flow or annular flow. Thereby a broad range of flow morphologies and different physical scales is involved. With the objective of reproduction of occurring phenomena with one single multi-fluid solver, we present an Euler-Euler-approach, which combines a number of different methods for treatment of the partial aspects. The implementation into OpenFOAM is always with focus on sustainable research, including a state-of-the-art IT concept. A segregated approach is used for treatment of the phase momentum equations, phase fraction equations and the pressure equation, featuring a consistent momentum interpolation scheme (Cubero et al., 2014). To fulfil the kinematic condition at resolved interfaces between different continuous phases, the latter may be coupled either by an isotropic (Strubelj and Tiselj, 2011) or by an anisotropic drag. In both cases, the immensely strong phase coupling requires an adapted numerical method. State and evolution of bubble size distribution in disperse phase context is solved with either class or moment methods. The overall objective is to take interactions between the all different aspects, such as disperse phases, resolved interfaces and turbulence with effects on momentum and mass transfer into account.

Fragestellung: Im Rahmen proximaler Humerusfrakturen sind neurovaskuläre Begleitverletzungen des unmittelbar benachbarten Plexus brachialis sowie der Arteria axillaris mit einer Prävalenz von 0,14 % bzw. 0,09 % eine Rarität, haben jedoch erhebliche Auswirkungen auf die Wahl [zum vollständigen Text gelangen Sie über die oben angegebene URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2018)

Industrial applications feature a huge variety of different flow patterns, such as bubbly flow, slug flow or annular flow. Thereby the issue of a big range of different physical scales is involved. With the objective of reproduction of occurring phenomena with one single multifluid solver, we present an Euler-Euler-approach, which combines a number of different methods for treatment of the partial aspects. The implementation into OpenFOAM is always with focus on sustainable research, including a state-of-the-art IT concept. A segregated approach is used for treatment of the phase momentum equations, phase fraction equations and the pressure equation, featuring a consistent momentum interpolation scheme (Cubero et al., 2014). To fulfill the kinematic condition at resolved interfaces between different continuous phases, the latter may be coupled either by an isotropic (Strubelj and Tiselj, 2011) or by an anisotropic drag. In both cases, the immensely strong phase coupling requires an adapted numerical method. State and evolution of bubble size distribution in disperse phase context is solved with either class or moment methods. The overall objective is to take interactions between the all different aspects, such as disperse phases, resolved interfaces and turbulence with effects on momentum and mass transfer into account.

Fragestellung: Zahlreiche Nahttechniken zur arthroskopischen Rekonstruktion der Rotatorenmanschette sind bis heute in der Literatur beschrieben worden. Ziel der vorliegenden Studie war, die biomechanischen Eigenschaften von 3 selbst-anziehenden ("self-cinching") Nahttechniken zu vergleichen.[zum vollständigen Text gelangen Sie über die oben angegebene URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2016)

The sequencing of the human genome and technological advances in DNA sequencing have led to a revolution with respect to DNA sequencing and its potential to diagnose genetic disorders. However, requests for open access to genomic data must be balanced against the guiding principles of the Common Rule for human subject research. Unfortunately, the risks to patients involved in genomic studies are still evolving and as such may not be clear to learned and well-intentioned scientists. Central to this issue are the strategies that enable human participants in such studies to remain anonymous, or de-identified. The wealth of genomic data on the Internet in genomic data repositories and other databases has enabled de-identified data to be broken and research subjects to be identified. The security of de-identification neglects the fact that DNA itself is an identifying element. Therefore, it is questionable whether data security standards can ever truly protect the identity of a patient, under the current conditions or in the future. As Big Data methodologies advance, additional sources of data may enable the re-identification of patients enrolled in next-generation sequencing (NGS) studies. As such, it is time to re-evaluate the risks of sharing genomic data and establish new guidelines for good practices. In this commentary, I address the challenges facing federally funded investigators who need to strike a balance between compliance with federal (US) rules for human subjects and the recent requirement for open access/sharing of data from National Institute for Health (NIH)-funded studies involving human subjects.