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Atomistic simulations have progressively attracted attention in the study of physical-chemical properties of innovative nanomaterials. GROMACS and LAMMPS are currently the most widespread open-source software for molecular dynamics simulations thanks to their good flexibility, numerous functionalities and responsive community support. Nevertheless, the very different formats adopted for input and output files are limiting the possibility to transfer GROMACS simulations to LAMMPS. In this article, we present GRO2LAM, a modular and open-source Python 2.7 code for rapidly translating input files and parameters from GROMACS to LAMMPS format. The robustness of the tool has been assessed by comparing the simulation results obtained by GROMACS and LAMMPS, after the format conversion by GRO2LAM. Specifically, three nanoscale configurations of interest in both engineering and biomedical fields are studied, namely a carbon nanotube, an iron oxide nanoparticle, and a protein immersed in water. In perspective, GRO2LAM may be the first step to achieve a full interoperability between molecular dynamics software. This would allow to easily exploit their complementary potentialities and post-processing functionalities. Moreover, GRO2LAM could facilitate the cross-check of simulation results, guaranteeing the reproducibility of molecular dynamics models and testing their robustness. Graphical Abstract GRO2LAM, a modular and open-source Python code for rapidly translating input files and parameters from GROMACS to LAMMPS format.

Background: Ultrasound-guidance has become the routine method for internal jugular vein (IJV) catheterization reducing dramatically failure and complication rates for central venous port (CVP) placement., Aims: The aim of this study was to determine the safety and efficacy of ultrasound-guided IJV CVP placement in elderly oncologic patients., Methods: Between January 2013 and December 2015, 101 elderly oncological patients underwent right IJV CVP placement under ultrasound-guidance. The length of catheter introduction ranged from 18 to 21 cm. Intraoperative fluoroscopy (IF) was always performed intraoperatively. Chest X-ray (CXR) was always performed 30 min after the end of the procedure., Results: The morbidity rate was 1.98%; two arterial punctures were reported with one self-limiting hematoma. Two patients (1.98%) had catheter misplacements, recognized by intraoperative IF. No patients (0%) experienced pneumothorax (PNX), confirmed at CXR. Patients were all discharged at maximum 6 h from the procedure., Discussion: The risk of catheter misplacement, PNX, and arterial/nerve puncture remains present with this technique. Lower rates of catheter misplacement have been reported after right IJV puncture, probably for its straight vertical course. Our results are in accordance with literature (1 counter-lateral subclavian vein and 1 counter-lateral internal jugular vein misplacements). All misplacements were detected intraoperatively. The PNX rates after cannulation of the IJV vary between 0.0 and 0.5%. We had no PNX occurrence., Conclusion: Ultrasonography (US) has improved safety and effectiveness of port system placements. While routine post-procedural CXR seems avoidable, IF should be considered mandatory.