Neurocysticercosis in Europe: Still a public health concern not only for imported cases.

Neurocysticercosis (NCC), a parasitic disease caused by the larvae of the cestode Taenia solium, is the most frequent parasitic disease of the central nervous system (CNS) in the world and the leading cause of secondary epilepsy in Central and South America, East and South Asia, and sub-Saharan Africa. It is endemic in many low- and middle-income countries of the world. Due to increased travels and immigration, NCC may be diagnosed also in non-endemic areas. In fact, tapeworm carriers from endemic zones can transmit infection to other citizens or arrive already suffering NCC. This phenomenon, occurred first in USA during the last 30 years, has been also observed in Europe, as well as in Australia, Canada, Israel, Japan and Muslim countries of the Arab World. Actually, concerning Europe, although, in some areas only few cases have been described, nevertheless the prevalence of NCC may be considered increasing, especially in Spain and Portugal. We reviewed the literature on the burden of NCC in Europe, by a search of PubMed regarding papers from 1970 to present. We only considered on PubMed published and available papers in English, French, Italian, and Spanish, the languages understood by the authors. One hundred seventy six cases of NCC have been reported in seventeen European countries (Austria, Belgium, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Netherlands, Sweden, United Kingdom, and Croatia, Norway, Switzerland). A particular epidemic situation is present in Spain and Portugal. In fact, we collected data that show, in Spain, an increasing incidence both in immigrated patients and in those which were born in certain Spanish geographical areas and, in Portugal, prevalence similar to that observed in endemic areas. Globally, it is clear that as a result of increased migrations and travels from endemic regions, NCC is becoming an emerging public health problem in high-income countries, particularly affecting communities where hygiene conditions are poor and sub-sequentially the parasite can spread from human to human through eggs even in absence of a travel to the tropics. NCC is a preventable disease, it derives that it's important to acquire a great consciousness of the epidemiology and to implement accurate surveillance systems

Simultaneous Contralateral Vestibular Schwannoma and Middle Ear Paraganglioma Tumor

To the best of our knowledge, only 2 cases of a simultaneous contralateral vestibular schwannoma (VS) and middle ear paraganglioma (MEP) have previously been reported in literature. We report the third case observed in a 43-year-old male, who presented with an 11-year history of right-sided hearing loss and a 1-year history of left-sided pulsatile tinnitus. A magnetic resonance imaging (MRI) showed a VS on the right side and computer tomography (CT) identified a Fisch type A1 paraganglioma on the left side. The VS was treated using a translabyrinthine approach and the MEP was kept under radiological observation for 1 year. Due to the growth of the MEP (Fisch type A2), it was treated with excision via a retroauricular approach. Our case was very challenging because there was a different and important pathology on each side, both carrying a risk of deafness as a consequence of the disease and/or the treatments

Multiscale properties of polymeric insulating materials: from microscale polarizability to macroscale permittivity

This article presents an innovative and easy way for the calculation of the real part of permittivity for some of the most common insulating materials used for electrical applications, namely: polyethylene (PE), polypropylene (PP), polytetrafluorethylene (PTFE), ethylene-propylene diene monomer (EPDM), polyamide-imide (PAI), and epoxy resin (EP). This is achieved by the implementation and validation of the additivity approach for polarizability, along with the derivation of molecular volumes by means of chemical calculations involving real density of the considered materials. The proposed approach significantly reduces the computational time and effort for the calculation of macroscopic permittivity. Simulated values show good accordance with experimental results, thus validating the approach

Broadband dielectric spectroscopy: A viable technique for aging assessment of low-voltage cable insulation used in nuclear power plants

This paper deals with the study of a non-destructive technique to detect the aging state of cable insulation used in a nuclear environment subjected to radiation and temperature aging. Cable samples were aged under dose rates ranging from 0.42 and 1.06 kGy/h at 55 and 85 °C. The imaginary part of the permittivity at 100 kHz is found to correlate well with mechanical properties, such as elongation at break, which is typically used to diagnose cable insulation, but it is a destructive property and cannot be used on field. It has been demonstrated also that a postirradiation effect occurs even years after aging is stopped, increasing the imaginary permittivity and worsening mechanical properties due to the slow conversion of radicals into oxidized species. The main consequence is that when cable insulation is subjected to a nuclear accident, releasing a huge amount of radiation, the health of cable insulation must be followed also for a long time after the accident occurred, since aging due to oxidation progresses even when the radiation source is switched off

Additive impact on space charge of XLPE-based insulators subjected to radio-chemical aging

This work investigates the development of space charge distribution through by means of the pulsed-electroacoustic method on differently-filled XLPE tapes subjected to radiochemical aging. The contribution of these different fillers on the space charge distribution and its evolution with aging is highlighted and linked with the physical-chemical properties (e.g. oxidation degree) of these materials

Analysis on the impact of additives on space charge behavior of thermally aged XLPE plaques

This article investigates the space charge properties of XLPE-based materials characterized by different concentration and types of additives and fillers inside the polymeric compound. Materials were aged under three different temperatures (87 °C, 110 °C and 130 °C) for 24, 18 and 12 months, respectively. Space charge profiles of both unaged and aged materials were obtained through the Pulsed Electro Acoustic (PEA) method. Additives and fillers are proven to significantly impact the space charge behavior of the insulating material both in the unaged and aged states. The impact of antioxidants, together with their kinetics under thermal aging conditions, is analyzed and claims an effective containment of the degradation kinetics, keeping the accumulated space charge to low values

Impact of additives and fillers on space charge behavior of polyethylene insulation: investigation and modeling

Diagnostic measurements on electrically insulating materials are a compulsory step to assure an acceptable service life of the electrical equipment. In particular, this paper focuses on the consequences of the implementation of several concentrations of antioxidants (Irganox® 1076 and Irganox® PSS02) inside Si-XLPE matrices. Thermally Stimulated Depolarization Current (TSDC) measurements were carried out on pure and filled samples to obtain information about the space charge behavior and trap distribution of the specimens. Postprocessing based on Randal-Wilkins model highlighted additive impact on Si-XLPE properties. Similar trap depth and different trap density values were found in samples with different concentrations of the same additive, suggesting a close correlation between the energy levels of localized states and the used antioxidants

Multi scale aging assessment of low-voltage cables subjected to radio-chemical aging: Towards an electrical diagnostic technique

In this article, the aging behavior of nuclear-grade low voltage cables, characterized by different geometries and insulation compositions, is investigated. Cables were subjected to radio-chemical aging at different dose rates (7 Gy/h, 66 Gy/h and 400 Gy/h), in order to simulate typical aging environments inside nuclear plants. The changes of insulation properties due to aging are investigated at different scales, aiming at highlighting possible correlations between molecular-scale properties and global macroscopic material behavior (e.g., mechanical and electrical ones). Microscale material behavior is investigated by means of FTIR spectroscopy and oxidation induction time (OIT) measurements, in order to evaluate material composition changes and material resistance to oxidation, respectively. On the other side, mechanical and electrical macroscopical properties are examined through tensile stress and dielectric spectroscopy measurements. It is found that aging is deeply influenced by the effect of additives (e.g. antioxidants) inside the insulation. In particular, the presence of antioxidants delays oxidation process allowing material modifications during the early aging states to be evaluated. Dielectric spectroscopy is demonstrated to properly follow all the stages of the degradation process, confirming its appropriateness as a non-destructive condition monitoring technique for cables. Finally, the evolution with aging of the dielectric response is associated with the variations of the considered chemical and mechanical properties, allowing the derivation of correlation master curves

Effects of Graphene Coatings on hindering Space Charge injection in Epoxy Resin

The reliability of epoxy resins (and dielectrics in general) employed for HVDC applications is significantly affected by space charge accumulation in the insulating material. Several methods have been tested to limit the injection and accumulation of space charge. In this work, planar specimens featuring graphene coatings were tested. Measurements of space charge accumulation, conductivity and permittivity at different temperatures (from 30°C to 60°C) and fields (from 30 kV/mm to 50 kV/mm) were carried out on epoxy specimens with and without coatings. Results show accumulation of space charge for low fields and temperatures in the reference specimens, while a reduction can be noticed with a layer of graphene coating. On the other hand, at higher fields or temperatures, the effect is reversed

Towards a Kinetic Modeling of the Changes in the Electrical Properties of Cable Insulation During Radio-Thermal Ageing in Nuclear Power Plants. Application to Silane-Crosslinked Polyethylene

The radio-thermal ageing of silane-crosslinked polyethylene (Si-XLPE) was studied in air under different γ dose rates (6.0, 8.5, 77.8, and 400 Gy·h-1) at different temperatures (21, 47, and 86 °C). The changes in the physico-chemical and electrical properties of Si-XLPE throughout its exposure were determined using Fourier transform infrared spectroscopy coupled with chemical gas derivatization, hydrostatic weighing, differential scanning calorimetry, dielectric spectroscopy and current measurements under an applied electric field. From a careful analysis of the oxidation products, it was confirmed that ketones are the main oxidation products in Si-XLPE. The analytical kinetic model for radio-thermal oxidation was thus completed with relatively simple structureproperty relationships in order to additionally predict the increase in density induced by oxidation, and the adverse changes in two electrical properties of Si-XLPE: The dielectric constant ε' and volume resistivity R. After having shown the reliability of these new kinetic developments, the lifetime of Si-XLPE was determined using a dielectric end-of-life criterion deduced from a literature compilation on the changes in R with ε' for common polymers. The corresponding lifetime was found to be at least two times longer than the lifetime previously determined with the conventional end-of-life criterion, i.e., the mechanical type, thus confirming the previous literature studies that had shown that fracture properties degrade faster than electrical properties