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This work aimed to estimate the distribution of the electric field generated by a combined cerebellar and frontal transcranial direct current stimulation (tDCS) for treatment-resistant depression using electromagnetics computational techniques applied to a realistic head human model. Results showed that the stronger electric fields occur mainly in the cerebellum and in DLPFC areas, where the two pairs of electrodes were applied. Furthermore, the study demonstrated that the simultaneous use of the two pairs of electrodes did not imply a lower effectiveness of the tDCS technique, in fact the electric field distributions in the primarily targets of the anatomical regions (i.e., cerebellum and DLPFC) were very similar to when the pairs of electrodes were applied separately.

This study is based on the quantification of the influence of the presence of gold nanoparticles (Au NPs), of their geometry and their distance from cell membrane during time-varying electromagnetic fields cell membrane permeabilization on the pores opening dynamics. Results showed that the combined use of Au NPs and time-varying magnetic field can improve significantly the permeabilization of cell membrane. The presence of Au NPs allowed to reach transmembrane potential values enabling the cell membrane permeabilization only when placed at very short distance, equal to 20 nm. Both geometry and variability of the positioning in proximity of the cell membrane showed a strong influence on the probability of enabling pores opening. Clinical Relevance- This study provides a better comprehension about the mechanisms, still not completely understood, underlying cell membrane permeabilization by combining Au NPs and time-varying magnetic fields.

The feasibility of using time-varying magnetic field as a contactless cells permeabilization method was demonstrated by experimental results, but the underlying mechanism is still poorly understood. In this study a numerical analysis of the transmembrane potential (TMP) at cell membranes during permeabilization by time-varying magnetic fields was proposed, and a first quantification of mechanical stress induced by the magnetic and electric fields and hypothesized to play an important role in the permeabilization mechanism was carried out. TMP values induced by typical in-vitro experimental conditions were far below the values needed for membrane permeabilization, with a strong dependence on distance of the cell from the coil. The preliminary assessment of the mechanical pressure and potential deformation of cells showed that stress values evaluated in conditions in which TMP values were too low to cause membrane permeabilization were comparable to those known to influence the pore opening mechanisms.Clinical Relevance- Results represent a significant step towards a better comprehension of the mechanism underlying cell membrane permeabilization by time-varying magnetic fields.

In recent years the introduction of 5G networks is causing a drastically change of human exposure levels in the radio frequency range. The aim of this paper is on expanding the knowledge on this issue, assessing the exposure levels for a particular case of indoor 5G scenario, where the presence of an Access Point (AP) was simulated. Coupling the traditional deterministic computational method with an innovative stochastic approach, called Polynomial Chaos Kriging, allowed to evaluate the exposure variability of an user considering the 3D beamforming capability of the antenna. The exposure levels, expressed in terms of specific absorption rate (SAR) in specific tissues, showed low values compared to ICNIRP guidelines.

This paper evaluates the dose of exposure to radiofrequency electromagnetic fields (EMF) of people inside a car during vehicle-to-vehicle (V2V) communication operated at 5.9 GHz. The exposure dose is estimated with numerical simulations that make use of detailed and realistic 3D models of the geometry and material of the car and V2V antennas and of the organs and different tissues of an adult phantom at the driver position. The dose of EMF exposure was expressed in terms of the power absorbed by the tissues and organs of the driver and was quantified with the Specific Absorption Rate (SAR). The simulations revealed that SAR was higher in the body regions closer to the emitting antennas (the limbs) and very rapidly decreased with the distance from the antennas. Also, SAR values were observed only in the very superficial tissues, i.e., in the skin and were negligible elsewhere, such as in the muscles, bones and other more profound tissues. SAR values for both the whole-body- and local-body-exposure were well below the ICNIRP general public exposure limit in the 100 kHz-6 GHz frequency range and were equal to 1% and 7% of the limits of exposure for the whole-body and local body regions, respectively.

International audience; This study focused on the evaluation of the electric field induced in the brain grey matter of a 5 years child when exposed to uniform magnetic field at 50 Hz with uncertain orientation. An innovative approach that combines Principal Component Analysis (PCA) and Gaussian process regression (Kriging method) in order to build space-dependent surrogate models was applied and validated. Preliminary results showed the feasibility of the approach.

The exposure of an 8-years child moving in a room to a 4G LTE femtocell with uncertain position was assessed by stochastic dosimetry based on sparse low rank tensor approximation method (sparse LRA). The Specific Absorption Rate (SAR) was estimated in all the possible positions of femtocell and child. Results showed that, for all the possible positions in the room, the exposure values were significantly below the International Commission of Non-Ionizing Radiation Protection (ICNIRP) guidelines for general public exposure. The variation of the distance between femtocell and child influenced greatly the exposure, resulting in Quartile Coefficient of Dispersion value equal to 67%.

This study focused on the evaluation of the electric field induced in a 5 years child tissues exposed to uniform magnetic field at 50 Hz with uncertain orientation. An innovative approach combining Principal Component Analysis and Kriging method was proposed to build space-dependent surrogate model. Preliminary results showed the feasibility of the approach.

Aim of this study is to quantify by means of computational electromagnetic techniques the electric field distribution (E) induced by a specific H-coil (named H4) used for deep Transcranial magnetic stimulation precisely designed for the addiction treatment.

The beneficial effects of transcranial direct current stimulation (tDCS) has been demonstrated, but the neuroscientific community is working to increase its efficiency. A promising line of advancement may be reducing the inter-individual variability of the response through the personalization of the stimulation, adapted to fit the structural and functional features of individual subjects. In this paper, we approach the personalization of stimulation parameters using modeling, a powerful tool to test montages enabling the optimization of brain's targeting.

Focus on the late preterm birth (LPB) and critical congenital heart defects (CCHD) Data on outcomes of CCHD specifically in late preterm infants are exceedingly scarce. The preterm newborn with associated complex CHD presents many intricate problems to clinicians who take care (neonatologist, cardiologist, cardiothoracic surgeon). Therapies used for the preterm neonate without heart disease frequently need to be altered in the presence of heart disease and those needed for management of heart disease may need to be altered because of prematurity. The population of newborn born preterm is at higher risk for postoperative death and short and long term complications than term newborn with the same CHD and the causes of this are multifactorial. Technical issue related to small cardiac structure, immaturity of other organ systems, decreased nutritional and cardiac reserve, increased risks of bleeding, abnormal chest wall mechanics after sternotomy can all together account for this epidemiologic data. In past years these findings were related in particular to low-birth weight infants and conventional management was oriented to await a threshold weight in order to reduce bypass-related morbidities. From 1990 rates of LPB have risen and now account for 75% of all preterm births. Whether late preterm infants with CHD, who may be only marginally more immature than their term counterparts, remain at risk for adverse outcome in unclear. Some recent papers do demonstrate the independent effect of LPB on mortality and morbidity if a CHD is present and this issue emerge as an important factor for a correct counseling. Natarajan have observed that the weight at surgical intervention was significantly lower and age higher in the late preterm infants compared to those delivered at term. Late preterm infants had significantly higher rates of NEC and seizures, with a greater risk of supplemental oxygen and tube feeding at discharge. Costello have examined mortality and morbidity stratified by gestational age, reporting for LPB group with CHD an hospital mortality rate of 16.4% compared to 2.6-8% in the term group. The exact mechanism of this vulnerability remains unclear although functional immaturity of the lung and the brain are plausible aetiologies. Altered intrinsic cardiac mechanism could play a role in adverse outcome of late preterm with CHD. Gestational age at delivery can be a risk factor over which clinicians might have some control. Before birth the challenge is planning the time and the place for the delivery of a foetus with CHD. After birth the challenge is not waiting for obtain an arbitrary correct weight for surgery but working in a complex team to discuss each case in order to maximize outcome. Domande inerenti la relazione del Dott. Stefano Fiocchi

As only few studies have addressed biological effects of radiofrequency energy absorption of novel wireless technologies in living body, we set out 1) to design and test a unique Wi-Fi exposure system and 2) to investigate the effects of single 60 min Wi-Fi electromagnetic field (EMF) exposure on neurophysiological brain function assessed by recording spontaneous scalp EEG (sEEG) and 3) on human cognitive performance assessed in a computerized version of Psychomotor Vigilance Task (PVT). Specific absorption rate (SAR) were modeled with commercial simulation platforms, using whole-body, realistic, positioned, sitting human voxel models (female/male) and was found to 1W input over 10g 227.67/103.68mW/kg on forehead skin, 27.02/16.01mW/kg on grey matter, 11.57/7.33mW/kg on white matter. Twenty-five healthy volunteers participated in two experimental sessions (genuine or sham EMF irradiation) in a double-blind design. sEEG data were collected from midline electrodes while subjects were watching a silent documentary clip. In a different experiment, 19 healthy volunteers participated performing PVT, where reaction time (RT) data were registered. Normalized SAR indicated differences between genders. During exposure, sEEG spectral components in the alpha band revealed significant Irradiation × Gender interaction (p = 0.04) with no further differences in the post hoc analyses. According to RT data, PVT results did not reveal any significant Gender or Irradiation effects. Although the present results do not support any adverse effects of acute Wi-Fi EMF exposure on sEEG or PVT measures, further investigation will be needed to provide conclusive evidence in the matter of possible gender-related differences.

In this paper we present a tool for the intelligent retrieval of past cases to support Insulin Dependent Diabetes Mellitus patients therapy revision. This tool was designed for assisting physicians during periodical monitoring visits. Each case is represented through i) a collection of features that describe the patient's clinical state at the decision time, i.e. the control visit, ii) the decision taken in terms of therapy revision and iii) the outcome obtained on the metabolic control during the following monitoring period. A new case is first classified into a protypical monitoring situation, and then similar cases are retrieved and shown to the user. This tool is fully integrated in a Web-based distributed system for Diabetes Management, developed within in the EU project T-IDDM.

This paper outlines the methodologies that can be used to perform an intelligent analysis of diabetic patients' data, realized in a distributed management context. We present a decision-support system architecture based on two modules, a Patient Unit and a Medical Unit, connected by telecommunication services. We stress the necessity to resort to temporal abstraction techniques, combined with time series analysis, in order to provide useful advice to patients; finally, we outline how data analysis and interpretation can be cooperatively performed by the two modules.