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PACS:47.51.+a, 47.27.Gs, 47.27.tb ; An inert dynamically passive scalar in a constant density fluid forced by a statistically homogeneous field of turbulence has been investigated using the results of a 2563 grid direct numerical simulation. Mixing characteristics are characterized in terms of either principal curvatures or mean and Gauss curvatures. The most probable small-scale scalar geometries are flat and tilelike isosurfaces. Preliminary correlations between flow and scalar small-scale structures associate highly curved saddle points with large-strain regions and elliptic points with vorticity-dominated zones. The concavity of the scalar profiles along the isosurface normal coordinate xn correlates well with negative mean curvatures, Gauss curvatures displaying any sign, which correspond to scalar minima, tiles, or saddle points; on the other hand, convexity along xn is associated with positive mean curvatures, Gauss curvatures ranging from negative to positive signs, featuring maxima, tiles, or saddle points; inflection points along xn correlate well with small values of the mean curvature and zero or negative values of kg, corresponding to plane isosurfaces or saddle points with curvatures of equal and opposite signs. Small values of the scalar gradient are associated with elliptic points, either concave or convex (kg>0), for both concave and convex scalar profiles along xn. Large values of the scalar gradient (or, equivalently, scalar fluctuation dissipation rates) are generally connected with small values of the Gauss curvature (either flat or moderate-curvature tilelike local geometries), with both concave and convex scalar profiles along xn equally probable. Vortical local flow structures correlate well with small and moderate values of the scalar gradient, while strain-dominated regions are associated with large values. ; A part of this work has been performed under the auspices of the INTAS project 353 of the European Union. Juan Hierro would like to thank the Spanish Government and the Fulbright Commission for their support to spend one year at the Johns Hopkins University. The financial support of the DGA to the Computational Fluid Mechanics Group of the University of Zaragoza/LITEC is also acknowledged. ; Peer reviewed

An experimental and numerical study has been performed to improve the understanding of the air/liquid interaction in an air-blasted breaking water sheet. This research is focused in the near field close to the exit slit, because it is in this region where instabilities develop and grow, leading to the sheet breakup. In the experiments, several relevant parameters were measured including the sheet oscillation frequency and wavelength, as well as the droplet size distribution and the amplification growth rate. The flow was also investigated using linear instability theory. In the context of existing papers on instability analysis, the numerical part of this work presents two unique features. First, the air boundary layer is taken into account, and the effects of air and liquid viscosity are revealed. Second, the equations are solved for the same parameter values as those in the experiments, enabling a direct comparison between calculations and measurements; although qualitatively the behaviour of the measured variables is properly described, quantitative agreement is not satisfactory. Limitations of the instability analysis in describing this problem are discussed. From all the collected data, it is confirmed that the oscillation frequency strongly depends on the air speed due to the near-nozzle air/water interaction. The wave propagates with accelerating interface velocity which in our study ranges between the velocity of the water and twice that value, depending on the air velocity. For a fixed water velocity, the oscillation frequency varies linearly with the air velocity. This behaviour can only be explained if the air boundary layer is considered. ; This project has been partially supported by the Comision Interministerial de Ciencia y Tecnolog a of the Spanish Government under contract AMB96-0427-C03- 01, and the Direccion General de Estudios Superiores under contracts PB96-0739- C03-03 and BFM2000-1328. The authors want to thank the referees for their insightful comments. ; Peer reviewed

Introduction Surgical oncology is a defined specialty within the European Board of Surgery within the European Union of Medical Specialists (UEMS). Variation in training and specialization still occurs across Europe. There is a need to align the core knowledge needed to fulfil the criteria across subspecialities in surgical oncology. Material and methods The core curriculum, established in 2013, was developed with contributions from expert advisors from within the European Society of Surgical Oncology (ESSO), European Society for Radiotherapy and Oncology (ESTRO) and European Society of Medical Oncology (ESMO) and related subspeciality experts. Results The current version reiterates and updates the core curriculum structure needed for current and future candidates who plans to train for and eventually sit the European fellowship exam for the European Board of Surgery in Surgical Oncology. The content included is not intended to be exhaustive but, rather to give the candidate an idea of expectations and areas for in depth study, in addition to the practical requirements. The five elements included are: Basic principles of oncology; Disease site specific oncology; Generic clinical skills; Training recommendations, and, lastly; Eligibility for the EBSQ exam in Surgical Oncology. Conclusions As evidence-based care for cancer patients evolves through research into basic science, translational research and clinical trials, the core curriculum will evolve, mature and adapt to deliver continual improvements in cancer outcomes for patients.