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Neuromorphic computing is promising to become a future standard in low-power AI applications. The integration between new neuromorphic hardware and traditional microcontrollers is an open challenge. In this paper, we present an interface board and a communication protocol that allows communication between different devices, using a microcontroller unit (Arduino Due) in the middle. Our compact printed circuit board (PCB) links different devices as a whole system and provides a power supply for the entire system using batteries as the power supply. Concretely, we have connected a Dynamic Vision Sensor (DVS128), SpiNNaker board and a servo motor, creating a platform for a neuromorphic robotic system controlled by a Spiking Neural Network, which is demonstrated on the task of intercepting incoming objects. The data rate of the implemented interface board is 24.64 k symbols/s and the latency for generating commands is about 11ms. The complete system is run only by batteries, making it very suitable for robotic applications.

Intensity measurements represent a well-established method to determine the sound power of an emitting object. The principal strength of this technique relies upon the possibility of performing the measurements in situ, with no special required conditions concerning the surrounding sound field. Commercially available sound intensity probes rely on two phase-matched microphones properly spaced concerning the desired frequency range. Given the physical and mathematical principles behind the intensity method, phase differences between the signals assume a crucial role. This report aims to study the possibility of designing a cost-effective acoustic phase calibrator to extract the intrinsic phase mismatch of standard class-1 microphones. A phase calibrator has been designed to identify phase mismatches between the microphones and provide the required corrections at specific frequencies. Numerical acoustical Finite Element Method (FEM). models of the calibrator configurations have been implemented. The results of the numerical models have lately led to three calibrator prototypes that have been produced by 3D-printing and tested. They have shown good results when compared to a commercially available and much more expensive acoustic coupler.

Multirotors are gaining great importance in the layout of innovative and more agile mobility. In this framework, a possible solution to developing an aircraft complying with the stringent size requirements characterizing this type of application may be a coaxial rotor configuration. To exploit several possibilities linked to coaxial rotors, a scaled experimental model is designed to evaluate the performances of the counter-rotating propeller system, specifically regarding the distance between the two propellers. Both thrust and noise are considered as parameters of interest. Two brushless motors are deployed, whereas the propellers’ angular velocity, in terms of rounds per minute (rpm), is controlled by an external control system. Tests are conducted on both single isolated propellers as well as on the counter-rotating system: the two propellers and their respective motors are characterized regarding the thrust. Furthermore, a comparison with a numerical model is performed. Noise evaluation on the single propeller shows a motor contribution prevalence at a low rpm range (1140–1500 rpm) and a propeller prevalence for angular velocities higher than 1860 rpm. By varying the distances between the propellers, a sensitivity analysis is performed with the aim of identifying the optimum configuration, taking into account both noise and thrust performances.

Introduction: Complete denervation of transplanted heart exerts protective effect against postoperative atrial fibrillation; various degrees of autonomic denervation appear also after transection of ascending aorta during surgery for aortic aneurysm. Objective: This study aimed to evaluate if the level of cardiac denervation obtained by resection of ascending aorta could exert any effect on postoperative atrial fibrillation incidence. Methods: We retrospectively analysed the clinical records of 67 patients submitted to graft replacement of ascending aorta (group A) and 132 with aortic valve replacement (group B); all episodes of postoperative atrial fibrillation occurred during the 1-month follow-up have been reported. Heart Rate Variability parameters were obtained from a 24-h Holter recording; clinical, echocardiographic and treatment data were also evaluated. Results: Overall, 45% of patients (group A 43%, group B 46%) presented at least one episode of postoperative atrial fibrillation. Older age (but not gender, abnormal glucose tolerance, ejection fraction, left atrial diameter) was correlated with incidence of postoperative atrial fibrillation. Only among a subgroup of patients with aortic transection and signs of greater autonomic derangement (heart rate variability parameters below the median and mean heart rate over the 75th percentile), possibly indicating more profound autonomic denervation, a lower incidence of postoperative atrial fibrillation was observed (22% vs. 54%). Conclusion: Transection of ascending aorta for repair of an aortic aneurysm did not confer any significant protective effect from postoperative atrial fibrillation in comparison to patients with intact ascending aorta. It could be speculated that a limited and heterogeneous cardiac denervation was produced by the intervention, creating an eletrophysiological substrate for the high incidence of postoperative atrial fibrillation observed.

Objective: A precise characterization of erectile dysfunction (ED) of vascular origin has not yet been achieved, although cavernous peak systolic velocity (PSV) is generally considered a major parameter. Nevertheless the penile dynamic color Doppler is invasive and linked to several complications. The intima-media thicknesses (IMT) of cavernosal artery would add to the predictive value of vasculogenic ED risk and outcomes. We also hypothesized the existence of a correlation between IMT cavernosal artery and IMT carotid arteries. This study seeks to evaluate these hypotheses with our experience, investigating the predictive accuracy of carotid and cavernosal Doppler ultrasound findings for discriminating patients with vasculogenic ED. Material and methods: A total of 59 subjects (32 vasculogenic ED patients - group A - and 27 no vasculogenic ED patients - group B) were evaluated in our andrological center from September 2012 to June 2013 and enrolled in the study. All subjects underwent medical history, erectile function domain of the International Index of Erectile Function, physical examination, routine and sex hormone blood tests, and high resolution dynamic color Doppler ultrasound evaluation of carotid and penile districts and valutation of IMT in both districts. Results: The values of cavernosal artery IMT in group A were higher than in group B (0,28 ± 0,06 mm vs 0,17 ± 0,07 mm). Even the values of carotid artery IMT in vasculogenic ED group were higher than in no vasculogenic ED group (0,74 ± 0,14 mm vs 0,59 ± 0,11 mm). The cavernosal IMT showed a moderate (r = 0.61) positive linear correlation (p < 0.001) with the carotid artery IMT. Conclusions: An increased cavernous IMT might predict ED of vascular origin with more accuracy than PSV and could be a sensitive predictor also for systemic atherosclerosis at an earlier phase.