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%.Covid-19 pandemic imposes crucial social distancing rules and restriction measures; therefore, the access to facilities and sites, in order to perform on-site inspections, became difficult or not feasible. Greek Atomic Energy Commission (EEAE) adopted remote virtual inspections (RVIs) of facilities and practices applying ionizing radiation and MRI installations, in order to continue discharging its regulatory duty of inspection, effectively. This study presents the experience gained and lessons learnt from the implementation of the RVIs and explores the RVIs perception by the stakeholders. Moreover, the effectiveness and the capability of RVIs to identify “findings”, is assessed by comparing the on-site and the remote inspections outcomes. The presented study showed that RVIs could not replace the on-site inspections, entirely; however, they could support and contribute to the inspection activities and program, in certain circumstances. RVIs were proven to be a valuable tool for the inspection of procedures, documents and records as well as the design and operational conditions of the facilities. The performance of remote verification tests and measurements, although feasible, was challenging, due to the technical issues needed to be resolved in advance. The comparison between remote and on-site inspections outcomes showed that both inspection options had similar capability to identify “findings”, indicating the validity of the RVIs as an inspection methodology in certain inspection thematic areas. The perception of the RVIs was positive and the added value and usefulness was acknowledged by the inspected facilities’ personnel and the EEAE’s inspectors, although the latter mainly considered RVIs as complementary and supportive to the on-site inspections.

The objective of this work is to develop a 4D (3D+T) statistical anatomical atlas of the electrical properties of the upper part of the human head for cerebral electrophysiology and bioimpedance applications.

The atlas was constructed based on 3D magnetic resonance images (MRI) of 107 human individuals and comprises the electrical properties of the main internal structures and can be adjusted for specific electrical frequencies. T1w+T2w MRI images were used to segment the main structures of the head while angiography MRI was used to segment the main artery. The proposed atlas also comprises a time-varying model of arterial brain circulation, based on the solution of the Navier-Stokes equation in the main arteries and their vascular territories.

High-resolution, multi-frequency and time-varying anatomical atlases of resistivity, conductivity and relative permittivity were created and evaluated using a forward problem solver for EIT. The atlas was successfully used to simulate electrical impedance tomogralems in cerebral electrophysiology and bioimpedance do not have analytical solutions for nontrivial geometries and require a 3D model of the head and its electrical properties for solving the associated PDEs numerically. Ideally, the model should be made with patient-specific information. In clinical practice, this is not always the case and an average head model is often used. click here Also, the electrical properties of the tissues might not be completely known due to natural variability. Anatomical atlases are important tools for in silico studies on cerebral circulation and electrophysiology that require statistically consistent data, e.g., machine learning, sensitivity analyses, and as a benchmark to test inverse problem solvers.Spoof plasmonic metamaterials enable the transmission of electromagnetic energies with strong field confinement, opening new pathways to the miniaturization of devices for modern communications. The design of active, reconfigurable, and nonlinear devices for the efficient generation and guidance, dynamic modulation, and accurate detection of spoof surface plasmonic signals has become one of the major research directions in the field of spoof plasmonic metamaterials. In this article, we review recent progress in the studies on spoof surface plasmons with a special focus on the active spoof surface plasmonic devices and systems. Different design schemes are introduced, and the related applications including reconfigurable filters, high-resolution sensors for chemical and biological sensing, graphene-based attenuators, programmable and multi-functional devices, nonlinear devices, splitters, leaky-wave antennas and multi-scheme digital modulators are discussed. The presence of active SSPPs based on different design schemes makes it possible to dynamically control electromagnetic waves in real time. The promising future of active spoof plasmonic metamaterials in the communication systems is also speculated.The Orsay Proton therapy Center (ICPO) has a long history of intracranial radiotherapy using both double scattering (DS) and pencil beam scanning (PBS) techniques, and is actively investigating a promising modality of spatially fractionated radiotherapy using proton minibeams (pMBRT). This work provides a comprehensive comparison of the organ-specific secondary neutron dose due to each of these treatment modalities, assessed using Monte Carlo (MC) algorithms and measurements. A MC model of a universal nozzle was benchmarked by comparing the neutron ambient dose equivalent, H*(10), in the gantry room with respective measurements obtained using a WENDI-II counter. The secondary neutron dose was evaluated for clinically relevant intracranial treatments of patients of different age groups, in which secondary neutron doses were scored in anthropomorphic phantoms merged with the patients’ images. The MC calculated H*(10) values showed a reasonable agreement with the measurements and followed the expected tendency, in which PBS yields the lowest dose, followed by pMBRT and DS. Our results for intracranial treatments show that pMBRT yielded a higher secondary neutron dose for organs closer to the target volume, while organs situated furthest from the target volume received a greater quantity of neutrons from the passive scattering beam line. To the best of our knowledge, this is the first study to realistically quantify the secondary neutron dose contribution of clinical pMBRT treatments. The method established in this study will enable epidemiological studies of the long-term effects of intracranial treatments at ICPO, notably radiation-induced second malignancies.In 2021, the ICRP initiated the revision of the general recommendations of the system of Radiation Protection, and part of it will focus on dose quantities. The recently published ICRP Publication 147 and ICRU Report 95 have described the extent of the proposed modifications and paved the way for the strategy to be adopted. These revisions would seek to simplify, improve the accuracy and extend the field of use of dose quantities. While the Radiological Protection Working Group (RPWG) of the World Nuclear Association (WNA) recognises the notable improvement in the estimation of the protection quantities and the usefulness of such changes for the medical and research sector, the benefits of the proposed new system seem very limited for the nuclear industry and industries involving naturally occurring radioactive materials (NORM). The complexity associated with changing a long standing and robust system and the risk incurred by the human factor seem unjustified bearing in mind the likely cost.In this study, the electronic properties of J50N2200 (benzodithiophene-alt-benzotriazole NDI-bithiophene) interface before and after fluorination/chlorination were investigated based on the first-principles density functional theory (DFT). The results reveal that the donor (D) and acceptor (A) molecules exhibit direct band gap whether to be fluorinated/chlorinated or not, and the six DA pairs constructed all display indirect band gap. Next, for the fluorinated/chlorinated D molecule J50, the slope of total density of states (TDOS) curve edge at the highest occupied molecular orbital (HOMO) energy level enlarges, indicating high electron locality; the fluorination/chlorination of the A molecule N2200 reduces the slope of the TDOS at the HOMO level, and the electron delocalization strengthens. Then, the difference ΔE1 of the lowest unoccupied molecular orbital (LUMO) levels between D and A, the difference ΔE2 of HOMO levels between D and A, and the difference ΔE3 between the HOMO level of the D and the LUMO level of the A were calculated about the DA complexes. The consequences present that by using fluorine/chlorine (F/Cl) substitution at J50, ΔE1 and ΔE2 both decrease, and ΔE3 increases; for N2200, both ΔE1 and ΔE2 increase, and ΔE3 decreases. Since the higher open circuit voltage (VOC) is directly proportional to ΔE3, again ΔE1 and ΔE2 afford the driving force for charge transport, these expose that the fluorination/chlorination of J50 is beneficial to obtain the higherVOC, meanwhile, the F/Cl replacement in N2200 facilitates the separation of excitons. In addition, by the Bader charge analysis, the F/Cl substitution at D in DA blends will promote the intramolecular charge transfer and enhance the molecular polarity; moreover, the substitution at A will improve the intermolecular charge transfer and the dipole electric field may be enhanced. Finally, the details also depend on the type of element and the position of substitution.Motivated by the recent experimental discovery of C6N7 monolayer, we show that C6N7 monolayer co-doped with C atom is a Dirac half-metal by employing first-principle density functional theory calculations. The structural, mechanical, electronic and magnetic properties of the co-doped C6N7 are investigated by both the PBE and HSE06 functionals. Pristine C6N7 monolayer is a semiconductor with almost isotropic electronic dispersion around the Γ point. As the doping of the C6N7 takes place, the substitution of an N atom with a C atom transforms the monolayer into a dilute magnetic semiconductor, with the spin-up channel showing a band gap of 2.3 eV , while the spin-down channel exhibits a semimetallic phase with multiple Dirac points. The thermodynamic stability of the system is also checked out via AIMD simulations, showing the monolayer to be free of distortion at 500 K. The emergence of Dirac half-metal in carbon nitride monolayer via atomic doping reveals an exciting material platform for designing novel nanoelectronics and spintronics devices.Two-dimensional (2D) materials such as MoS2 have extrodinary properties and significant application potential in electronics, optoelectronics, energy storage, bioengineering, etc. To realize the numerous application potential, it is needed to modulate the structure and properties of these 2D materials, for which ion beam irradiation has obvious advantages. This research adopted classical molecular dynamics simulations to study the sputtering of atoms in 2D MoS2, defect formation and the control rule under Ar ion beam irradiation, considering the influence of ion irradiation parameters (i.e., ion beam energy, ion dose), layer number of 2D MoS2, substrate. Furthermore, the uniaxial mechanical performance of the ion-irradiated nanostructures was investigated for actual applications loading with mechanical stress/strain. This research could provide important theoretical support for fabricating high-performance 2D MoS2-based nanodevices by ion beam irradiation method.