Prysmian Group (Italy)

As High Voltage Direct Current (HVDC) technology becomes increasingly important for the integration of large-scale renewable energy sources and to ensure efficient long-distance power transmission, an accurate assessment of insulation performance is necessary to maintain system reliability and minimize fault risks. In this scenario, the measurement of space charge in dielectric materials is useful for optimizing insulation systems for HVDC equipments. The Pulsed Electro-Acoustic (PEA) method is one of the most widely used techniques for space charge analysis, but distortions introduced by the measurement system significantly affect the accuracy of the acquired signals. Among the various factors influencing the acquisition of the space charge profile is the convolution process between the signal and the measuring cell, which is characterized by its own transfer function. Therefore, signal deconvolution is essential for accurately reconstructing the space charge distribution. This paper presents a comparative review of the deconvolution techniques suggested by researchers in the field of PEA measurement. Theoretical principles, advantages, and limitations of methods such as Fourier and Wiener deconvolution are analyzed, along with advanced solutions based on Laplace and Short Time Fourier Transforms. Furthermore, the techniques have been implemented and tested in a MATLAB environment for practical comparison. The results demonstrate how the choice of technique influences the quality of the reconstructed signal, providing optimal selection criteria for different experimental conditions.

Space charge accumulation in High Voltage Direct Current (HVDC) cables is a critical issue that can affect insulation performance and system reliability. The IEEE 1732 standard provides a recommended practice for space charge measurement using the Pulsed Electro-Acoustic (PEA) method. The aim of the recommendation relying on three-hour interval spot measurements to assess electric field stabilization. However, this approach may not fully capture the dynamic behavior of the electric field, potentially leading to overestimated test durations or misinterpretations due to altered data. This paper proposes a statistical approach to evaluate electric field stabilization based on frequent data acquisition and statistical trend analysis. The proposed method is compared with the IEEE 1732 standard, demonstrating its potential to improve measurement accuracy.

Starting from a 2D finite element formulation for the computation of eddy currents in and around a submarine HVDC cable, we describe a procedure for extracting the sea and seabed return impedance parameters to be used in a network description of the system. A model order reduction approach, known as the Cauer Ladder Network method, is applied to extract a network representation of the earth return impedance of an HVDC submarine cable in a realistic scenario. In this work, the proposed method is described in detail, and the obtained numerical results are compared with well-known analytical formulas, showing how the extracted equivalent circuit approximates the reference results within acceptable tolerance.

IntroductionBisphenol A (BPA) is a common contaminant widely used in many industrial sectors. Because of its wide use and dispersion, it can be accumulated in living human bodies through both oral assumption and nondietary routes. BPA exhibits hormone-like properties, falling under the class of endocrine disruptors; therefore, it can alter relevant physiological functions. In particular, in women, it can affect folliculogenesis and therefore reproduction, contributing not only to infertility, but also to endometriosis and premature puberty.MethodsWe conducted a multicenter study on 91 women undergoing a first in vitro fertilization (IVF) treatment in the Campania region (Southern Italy). We investigated the presence and concentration of BPA in serum and follicular fluids to assess the effects of airborne BPA contamination. The analysis was conducted on 32 women living in a low environmental impact (LEI) area, from the Sele Valley River and Cilento region, and 59 women living in a high environmental impact (HEI) area, the so-called “Land of Fires”, a highly contaminated territory widely exposed to illegal waste practices.ResultsA higher average BPA content in both blood serum and follicular fluid was revealed in the HEI group when compared with the LEI group. In addition, we revealed higher average BPA content in blood serum than in folliclular fluid in the HEI area, with opposite average content in the two fluids in the LEI zone. In addition, our results also showed a lack of correlation between BPA content in follicular and serum fluids both in the overall population and in the HEI and LEI groups, with peculiar trends in different subsets of women.ConclusionFrom our results, we revealed a heterogeneity in the distribution of BPA content between serum and follicular fluid. Further studies are needed to unravel the bioaccumulation mechanisms of BPA in highly polluted and nonpolluted areas.

The Lattice Energy Converter (LEC) is a relatively simple gas-metal device that is able to directly generate an electric voltage and current by an unexplained mechanism, possibly related to LENR. Due to its simplicity and high reproducibility, the LEC is a very interesting experiment that may provide insights into LENR phenomena, as well as potentially being a practical new solid-state energy source. This paper describes a successful replication of a Lattice Energy Converter (LEC) and a number of experiments and observations made to investigate the nature of the effect and its electrical characteristics, and to exclude the presence of artefacts and conventional explanations. Compared to a control device, the active LEC was able to generate a stable voltage in excess of 300 mV and a current up to a few microamperes. These results are consistent with previous data published by the inventors and other replicators, so the good reproducibility of the device is confirmed. The primary and most interesting effect happening inside the device is the apparent ionization of the gas between the electrodes, allowing a significant current to flow through an otherwise insulating gap. The spontaneous voltage is instead a secondary effect, due to the presence of a bimetallic pair in contact with an ionized conductive medium, forming a kind of gas-phase battery.

Cannabidiol (CBD) exhibits neuroprotective, anti-inflammatory, and immunomodulatory properties, making it a promising candidate for addressing inflammatory skin disorders like atopic dermatitis. This study aimed to (i) investigate CBD's impact on lymphocyte proliferation and lymphocyte viability; (ii) assess in vitro cytotoxicity U937 cells (a human promonocytic cell line) of CBD/cytotoxicity of CBD on U937 cells; (iii) provide insights into CBD immunomodulatory potential, and (iv) evaluate suitability of CBD for treating inflammatory skin conditions. To this aim PBMCs from healthy donors were cultured with mitogen and two different CBD doses (0.1 and 1 mg/ml), assessing B and T cell proliferation through flow cytometry. CBD inhibited mitogen-induced lymphocyte proliferation, reducing the percentage of proliferating T and B cells. Notably, both CBD doses did not exhibit cytotoxicity on lymphocytes as revealed by viability assessment. We also analysed the effect of CBD on U937 cells using an optical microscopy approach. Interestingly, the higher dose of CBD exerted a cytotoxic effect on U937 cells, while the lower dose was well tolerated. We analysed the effect of an adjuvant treatment for atopic dermatitis with a CBD-containing cleansing cream in reducing itch. Notably, the treatment with the CBD-containing cleansing cream significantly reduced itch in patients suffering from atopic dermatitis. These findings affirm CBD's immunomodulatory characteristics, emphasizing its potential therapeutic application in inflammatory skin disorders.

This paper is focused on the measurement of space charge in flat specimens deriving from a cable subjected to the Pre-Qualification (PQ) test. In particular, before starting the PQ test and after finishing them, the flat specimens have been taken from the cable. This with the aim to evaluate the effect of PQ test on the space charge accumulation phenomenon. The PEA cell has been used for the space charge detection, while the Standard IEEE 1732-2017 has been followed for the measurement procedure. For both unaged and aged specimens, the space charge and the related electric field distribution have been reported in the paper. Measurement results highlight that the more accentuated electric field distortion has been observed during the test carried out on the aged specimen stressed under positive polarity.

In this work, a prototype of a new PEA cell configuration has been built and its principle of operation investigated and described. The reasons that led the authors to this work are due to the fact that the traditional cell still presents some issues. In particular, it known that that for cable specimens the reflection phenomenon and the signal attenuation are the main responsible factors that affecting the main output signal. Concerning the acoustic wave attenuation phenomenon, it was found that the signal magnitude can increase by replacing the metallic ground electrode with a polymeric acoustic coupler and the PVDF absorber with a metallic block. Based on this, after a description of the classic and the new PEA cell structure, in the present paper the acoustic wave behavior in the sensor/absorber interface has been simulated by means of a previously developed model. Simulation results show that in the new PEA cell the signal sensed by piezoelectric sensor is doubled in comparison with that detected in the traditional configuration. However, in the first experimental test carried out with the built PEA cell prototype in a model cable specimen it has been observed that the magnitude of the space charge profile needs to be further improved.

This paper extends a recent demonstration of a 2-line side 15-mode spatial division multiplexing network node. The node is based on fifteen 2 × 2 wavelength cross-connects (WXCs) to direct up to six 5 Tb/s, 15-mode, spatial super channels (SSCs). For this demonstration, we consider full add and drop, full express and partial add and drop network scenarios. The WXCs were made using three commercial 4 × 16 wavelength cross-connects, which were reprogrammed to each implement five identical 2 × 2 WXCs. The network node is demonstrated using a 6.1 km, 15-mode, multi-mode fiber (MMF) with a standard cladding diameter of 125 μm. This is the first field-deployed MMF and is installed in an underground tunnel in the city of L'Aquila, Italy. We further extend the network node to support up to 20 SSCs for a throughput per line side of 100 Tb/s. It is shown that the MIMO requirements for this type of systems is strongly dependent on the differential delays of the different modes propagating within the network node.

The Spritztube (ST) is an extraglottic airway device developed for humans. The aim of the study was to design an ST for rabbits and to evaluate its feasibility. The study was divided into two phases. Phase I: anatomical study on 12 rabbit cadavers to design 2 STs (8 and 10 Ch, external diameter) for rabbits. Phase II: fourteen privately owned rabbits were anaesthetised, and intubation was attempted using a ST. Tube size, the method for confirming the correct positioning, the number of attempts, the time needed for the correct positioning of the ST and complications were recorded. The ST placement was feasible in all rabbits. The positioning of the ST was completed in 2.1 ± 1 attempts in 43 ± 21.4 s. A correct placement was confirmed by the visualisation of the proximal cuff at visual inspection of the oral cavity (14/14), by the detection of the airflow (9/14 rabbits) and by the visualisation of a capnographic wave (14/14 rabbits). Only one rabbit developed respiratory distress after the ST placement. The results of the present study allowed designing a ST specific for rabbits which was used a supraglottic airway device for the maintenance of isoflurane anaesthesia in spontaneously breathing rabbits.