Eduardo Suarez

This study presents a comprehensive benchmarking of six commercially available peak expiratory flow meters (PFMs), using a precise experimental spirometric test bench. Eight peak expiratory flows (PEF) ranging from 59.40 to 688.80 L/min at three frequencies, were systematically applied to each device. Through a series of controlled tests, the devices’ precision, accuracy, linearity, inter-device variability, and dynamic response were meticulously evaluated across their full measurement range. Results reveal distinct performance characteristics among models, with some demonstrating high precision and accuracy in intermediate flow ranges, whereas others exhibited significant deviations at lower or higher flows. Inter-device variability was minimal except for specific models at lower flow rates. Dynamic response at varying frequencies indicated negligible impact on device readings. This benchmarking provides valuable insights for clinicians and researchers selecting appropriate PFMs for respiratory assessments.

Transcranial static magnetic stimulation has shown the capacity to decrease systematically the cortical excitability in the treatment of epilepsy. Nevertheless, the application of these therapies to non-focal epilepsies is limited. This paper investigates on the numerical evaluation of promising strategies based on the application of static magnetic fields with multiple magnets on children. Results show that a ten-magnet configuration on the child’s head generates a magnetic flux density of 0.10 T in more than 70% of the brain cortex and more than 0.05 T in deep areas near the brain’s base. Conversely, the interaction between individual magnetic fields leads to regions of lower flux density, suggesting that not only the number of magnets, but also their relative position and orientation, are critical parameters. Thus, based on image diagnosis, it is possible to define a personalising procedure and develop an effective therapy of global epilepsy that penetrates sufficiently into the brain´s volume.

Spirometry is one of the most effective and widely used techniques for analysing human respiratory conditions and diseases. However, traditional spirometry equipment is limited in its ability to simulate pathological conditions beyond normal breathing, and standardization guidelines for testing procedures may unintentionally hinder progress in developing novel respiratory devices. This research presents the design of a flexible spirometry bench capable of simulating a broader range of pulmonary behaviours, from resting breathing to forced spirometry and even cough-induced airflow, enabling the development and testing of respiratory devices. The key components include pneumatic cylinders simulating lung volumes, a motor-driven actuation system controlling piston movements, and a spirometer recording air volume and flow. A Programmable Logic Controller (PLC) coordinates the actuators, sensors, and other control mechanisms, ensuring precision and reliability during experiments. Three types of tests were conducted: (1) reproducing periodic quiet breathing conditions using two predefined sinusoidal data sets, (2) acquiring a real spirometric curve from a patient, and (3) imposing a forced expiratory manoeuvre as input. The repeatability results, with the standard deviation not exceeding 0.1 and the coefficient of variation below 0.7%, highlight the high accuracy in reproducing curves. Maximum relative errors close to 1% were obtained for all analysed parameters during all tests performed. The test bench provides a flexible, high-precision platform for pulmonary research. Its wide operational range, precise control, and ability to replicate various respiratory scenarios make it a valuable tool for advancing respiratory health studies and supporting new therapeutic technologies by simulating real-life conditions.

Purpose: There are still many challenges for modelling a thrombus migration process in aneurysms. The main novelty of the present research lies in the modelling of aneurysm clot migration process in a realistic cerebral aneurysm, and the analysis of forces suffered by clots inside an aneurysm, through transient FSI simulations. Methods: The blood flow has been modelled using a Womersley velocity profile, and following the Carreau viscosity model. Hyperelastic Ogden model has been used for clot and isotropic linear elastic model for the artery walls. The FSI coupled model was implemented in ANSYS® software. The hemodynamic forces suffered by the clot have been quantified using eight different clot sizes and positions inside a real aneurysm. Results: The obtained results have shown that it is almost impossible for clots adjacent to aneurysm walls, to leave the aneurysm. Nevertheless, in clots positioned in the centre of the aneurysm, there is a real risk of clot migration. The risk of migration of a typical post-coiling intervention clot in an aneurysm, in contact with the wall and occupying a significant percentage of its volume is very low in the case studied, even in the presence of abnormally intense events, associated with sneezes or impacts. Conclusions: The proposed methodology allows evaluating the clot migration risk, vital for evaluating the progress after endovascular interventions, it is a step forward in the personalized medicine, patient follow-up, and helping the medical team deciding the optimal treatment. Graphical