Explore the vast range of titles available.

This paper introduces a novel architecture for optimizing radiation shielding using a genetic algorithm with dynamic penalties and a custom parallel computing architecture. A practical example focuses on minimizing the Total Ionizing Dose for a silicon slab, considering only the layer number and the total thickness (additional constraints, e.g., cost and density, can be easily added). Genetic algorithm coupled with Geant4 simulations in a custom parallel computing architecture demonstrates convergence for the Total Ionizing Dose values. To address genetic algorithm issues (premature convergence, not perfectly fitted search parameters), a Total Ionizing Dose Database Vault object was introduced to enhance search speed (data persistence) and to preserve all solutions’ details independently. The Total Ionizing Dose Database Vault analysis highlights boron carbide as the best material for the first layer for neutron shielding and high-Z material (e.g., Tungsten) for the last layers to stop secondary gammas. A validation point between Geant4 and MCNP was conducted for specific simulation conditions. The advantages of the custom parallel computing architecture introduced here, are discussed in terms of resilience, scalability, autonomy, flexibility, and efficiency, with the benefit of saving computational time. The proposed genetic algorithm-based approach optimizes radiation shielding materials and configurations efficiently benefiting space exploration, medical devices, nuclear facilities, radioactive sources, and radiogenic devices.

The use of neural electrodes to stimulate the Peripheral Nervous System (PNS) of upper limb amputees is giving promising results in restoring tactile feedback. The same interfaces could be used to record the motor activity originated from the brain and transferred to the muscles. In this paper, the possibility to control a prosthetic hand by means of neural signals acquired through tf-LIFE4 electrodes implanted in a human subject was investigated. A Support Vector Machine (SVM) algorithm was adopted to classify two common demanded grasps. The obtained classes were converted into reference positions for a position-and-slippage control strategy that guarantees to perform stable grasps with a prosthetic hand avoiding slippage events. The achieved results showed an accuracy of the classifier higher than 90% and a success rate of the control strategy equal to 100%.

Thermal neutron detection plays a crucial role in numerous scientific and technical applications such as nuclear reactor physics, particle accelerators, radiotherapy, materials analysis and space exploration. There are several challenges associated with the accurate identification and quantification of thermal neutrons. The present work proposes a detailed characterization of a Timepix3 (TPX3) detector equipped with a Lithium Fluoride ( 6 LiF) converter in order to study its response to thermal neutrons that are identified through the 6 Li(n, α ) 3 H reaction. The TPX3-based test system has been installed at the HOTNES facility in ENEA and the analysis highlighted its excellent performance showing high effectiveness in the identification of neutrons through morphological analysis of tracks produced by alpha and triton particles, after accurate discrimination from the gamma background. With the use of Monte Carlo simulations, it has been demonstrated that the main contribution is due to tritons and its signal can be used effectively in the identification of thermal neutrons obtaining an efficiency of 0.9 % for 25 meV neutrons. This allows the TPX3 to have important applications as an environmental monitor for thermal neutrons. This monitoring system can be simply realized and is easy to manage because of its compact size and its digital acquisition that allows a real-time analysis.

A fundamental requirement for assistive robots is to guarantee a safe and human-like way to perform their tasks. In particular, the ability to realize smooth movements and obtain a stable grasp is of primary importance. In this perspective, this paper aims at studying human grasping and developing a bio-inspired method for power-grip posture prediction and finger trajectory planning for a robotic hand. The developed method is based on neuroscientific assumptions and experimental evidence coming from the observation of the human behavior during power grip. It is based on the minimization of a suitably defined function to identify the optimal grasp configuration and the choice of a logarithmic spiral trajectory for moving the fingers. The behavior of ten different subjects during the grasping action has been analyzed with the CyberGlove motion capture data glove. A common thumb posture has been observed and has been introduced in the grasping algorithm. The algorithm performance has been tested on an anthropomorphic robotic hand by means of simulation trials. The results demonstrate the effectiveness of the approach and pave the way for the implementation on a real robotic hand.

Daily activities are characterized by an increasing interaction with smart machines that present a certain level of autonomy. However, the intelligence of such electronic devices is not always transparent for the end user. This study is aimed at assessing the quality of the remote control of a mobile robot whether the artefact exhibits a human-like behavior or not. The bioinspired behavior implemented in the robot is the well-described two-thirds power law. The performance of participants who teleoperate the semiautonomous vehicle implementing the biological law is compared to a manual and nonbiological mode of control. The results show that the time required to complete the path and the number of collisions with obstacles are significantly lower in the biological condition than in the two other conditions. Also, the highest percentage of occurrences of curvilinear or smooth trajectories are obtained when the steering is assisted by an integration of the power law in the robot’s way of working. This advanced analysis of the performance based on the naturalness of the movement kinematics provides a refined evaluation of the quality of the Human-Machine Interaction (HMI). This finding is consistent with the hypothesis of a relationship between the power law and jerk minimization. In addition, the outcome of this study supports the theory of a CNS origin of the power law. The discussion addresses the implications of the anthropocentric approach to enhance the HMI.

Results from the last FTU campaigns on the deuterium large (wrt FTU volume) pellet REs suppression capability, mainly due to the induced burst MHD activity expelling REs seed are presented for discharges with 0.5 MA and 5.3T. Clear indications of avalanche multiplication of REs following single pellet injection on 0.36 MA flat-top discharges is shown together with quantitative indications of dissipative effects in terms of critical electrical field increase due to fan-like instabilities. Analysis of large fan-like instabilities on post-disruption RE beams, that seem to be correlated with low electrical field and background density drops, reveal their strong RE energy suppression capability suggesting a new strategy for RE energy suppression controlling large fan instabilities. We demonstrate how such density drops can be induced using modulated ECRH power on post-disruption beams.

Considerable variations in the incidence of psychosis have been observed across countries, in terms of age, gender, immigration status, urbanicity and socioeconomic deprivation. To evaluate the incidence rate of first-episode psychosis in a large area of north-eastern Italy and the distribution of the above-mentioned risk factors in individuals with psychoses. Epidemiologically based survey. Over a 3-year period individuals with psychosis on first contact with services were identified and diagnosed according to ICD-10 criteria. In total, 558 individuals with first-episode psychosis were identified during 3,077,555 person-years at risk. The annual incidence rate per 100,000 was 18.1 for all psychoses, 14.3 for non-affective psychoses and 3.8 for affective psychoses. The rate for all psychoses was higher in young people aged 20-29 (incidence rate ratio (IRR) = 4.18, 95% CI 2.77-6.30), immigrants (IRR = 2.26, 95% CI 1.85-2.75) and those living in the most deprived areas (IRR = 2.09, 95% CI 1.54-2.85). The incidence rate in our study area was lower than that found in other European and North American studies and provides new insights into the factors that may increase and/or decrease risk for developing psychosis.

Most studies on gender and psychosis have focused on gender differences at illness onset or on the long-term outcome, whereas little is known about the impact of gender on the first years after psychosis onset. A total of 185 first episode psychosis (FEP) patients were followed for 5 years after psychosis onset, and gender differences were explored in psychopathology (PANSS), needs for care (CAN), and insight (SAI-E). Male patients showed more negative symptoms than females over time, whereas female patients showed higher levels of depressive symptoms than males throughout the study period. In addition, female patients presented more functioning unmet needs for care, but higher levels of insight into illness than males. Therapy and rehabilitative programs for FEP patients should be gender-targeted, as gender has proved to impact on psychopathology, needs for care, and insight in the very first years following psychosis onset.

Microrecordings of three neurons were obtained at the target site in three patients with trigeminal autonomic cephalalgias who were implanted with deep brain stimulators in the posterior hypothalamus. Two patients had chronic cluster headache, one short unilateral neuralgiform headache with conjunctival injection and tearing. Average firing rate was around 24 spikes/s. All neurons were firing randomly, and for most of the recordings in tonic fashion. In one patient, tactile stimulation of the ophthalmic branch, contralateral to the recording site, decreased the firing rate. Neuronal activity in these patients was similar to that reported in animal studies of the posterior hypothalamus. Positioning deep brain stimulators in the posterior hypothalamus may offer a tool to better characterise the activity of this part of the brain in humans.

Two patients with uncontrollable aggressive behaviour underwent the placement of stimulating leads in the posterior hypothalamus (pHyp). One patient had also multifocal refractory epilepsy. Microrecordings were obtained in both patients during surgery under general anaesthesia. Firing rate, interspike intervals and oscillatory discharge patterns were analysed in 14 neurons. A mean discharge rate of 19 Hz, and oscillatory activity at 7–8 Hz were recorded in the first patient with aggressiveness and epilepsy. In the second patient the mean firing rate was 10 Hz, with evidence of both tonic and random firing patterns. Previous studies in patients with cluster headache showed that a discharge rate around 20 Hz and lack of a specific rhythmic pattern were the most consistent characteristics of neuronal discharge in this area. Our present findings therefore would suggest that the pattern of discharge of neurons in the pHyp should be evaluated with reference to the presence of concurrent pathology.