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The high voltage Padova test facility (HVPTF) is an experimental device for the study of HV insulation in vacuum, in support of the realization of the prototype of a neutral beam injector for International Thermonuclear Experimental Reactor (ITER), named megavolt ITER injector and concept advancement (MITICA). The facility investigates the physical phenomena underlying voltage holding in vacuum, in particular the mechanisms causing breakdowns and the electrode conditioning process. At HVPTF, inside a high vacuum chamber, two stainless steel electrodes, separated by a few centimeters gap, can achieve HV values for a maximum potential difference of 800 kV. During the voltage conditioning of the electrodes, current MicroDischarges (MDs) and high-energy X-rays are observed and analyzed. In this work, we present a characterization of the MD dynamics occurring during the conditioning process, with the aim to gain information on the reason of the growing difference between the current contributions measured by the two electrodes. The analysis will be performed due to two new X-rays detectors recently installed: an lutetium yttrium orthosilicate (LYSO) and a LaBr3(Ce) scintillating crystal. The new diagnostics indeed provide the fine dynamics of a single MD, recording energy and time of each single detected X-ray. In particular, we compare the MD dynamics at the beginning and at the end of the conditioning process and try to give a preliminary interpretation of the observations.

ITER envisages the use of two heating neutral beam injectors plus an optional one as part of the auxiliary heating and current drive system, to reach the desired performances during its various phases of operation. The 16.5 MW expected neutral beam power per injector is several notches higher than worldwide existing facilities.In order to enable such development, a Neutral Beam Test Facility (NBTF) was established at Consorzio RFX, exploiting the synergy of two test beds, called SPIDER and MITICA. SPIDER is dedicated developing and char-acterizing large efficient negative ion sources at relevant parameters in ITER-like conditions: source and accel-erator located in the same vacuum where the beam propagates, immunity to electromagnetic interferences of multiple radio-frequency (RF) antennas, avoidance of RF-induced discharges on the outside of the source. Three years of experiments on SPIDER have addressed to the necessary design modifications to enable full perfor-mances. The source is presently under a long shut-down phase to incorporate learnings from the experimental campaign, in particular events/issues occurred during operation, which led to the identification of improvement opportunities/necessities (e.g. RF discharges, local burns, water leaks, other damages, configuration/design upgrades to maximize chances/margin to quest target parameters).Parallelly, developments on MITICA, the full-scale prototype of the ITER Neutral Beam Injector (NBI) featuring a 1 MV accelerator and ion neutralization, are underway including manufacturing of the beam source, accel-erator and the beam line components, while power supplies and auxiliary plants, already installed, are under final testing and commissioning.Integration, commissioning and tests of the 1 MV power supplies are essential for this first-of-kind system, unparalleled both in research and industry field. 1.2 MV dc insulating tests of high voltage components were successfully completed. The integrated test to confirm 1 MV output by combining invertor systems, DC gener-ators and transmission lines extracted errors/accidents in some components. To realize a concrete system for ITER, said events have been addressed and solutions for the repair and the improvement of the system were developed.Hence, NBTF is emerging as a necessary facility, due to the large gap with existing injectors, effectively dedicated to identify issues and find solutions to enable successful ITER NBI operations in a time bound fashion. The lessons learned during the implementation on NBTF and future perspectives are here discussed.

Both commercial and experimental antibacterial urinary catheters were investigated for their efficacy in preventing planktonic growth and biofilm formation of Escherichia Coli bacteria in a synthetic urine solution. Experimental antibacterial catheters having thin (2O, or Zn/Ag2O in polydimethylsiloxane (PDMS) binder all exhibited significant antimicrobial activity, outperforming traditional commercial antibacterial catheters. All experimental catheters prevented planktonic growth of bacteria and did not exhibit biofilm formation during a six-day test period using a colony forming unit (CFU) measurement method. On the other hand, the best performing commercial catheters demonstrated efficacy for only 3 days in planktonic growth tests and formed multiple bacterial colonies in CFU measurements. The Zn/Ag2O/PDMS experimental catheter was the only catheter observed to produce hydrogen peroxide, a reactive oxygen species known to inhibit biofilm formation; lack of detectable hydrogen peroxide production by the Ag2O/PDMS and Ag/Ag2O/PDMS experimental catheters suggests that bactericidal action most likely arises from release of silver ions present in the PDMS coatings.

A catheter coating consisting of polydimethylsiloxane (PDMS) mixed with powdered metals silver and zinc has been investigated. The coating is easily applicable to existing silicone devices and effective in inhibiting the formation of biofilm. Following manufacturing of the coating, its surface materials characteristics were analyzed through scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). The antibacterial properties of the coating were investigated by applying a thin film to the surface of a standard silicone catheter. A unique coating formulation of zinc and silver was found to inhibit biofilm and planktonic growth of E. coli over a six-day period, seemingly related to the release of heavy metal ions, generation of electric fields, hydrogen peroxide formation or combinations of these effects. Open-circuit cell potential for a zinc and silver foil was measured to be 1.2 V and 0.97 V within a deionized (DI) water and urine solution, respectively. Zone of inhibition experimental results suggest the possibility of silver ion diffusion when using mixed metals since bacteria formation is inhibited beyond the sample edge. Hydrogen peroxide measurements were taken over a period of 13 days for all samples. Samples containing zinc were found to produce hydrogen peroxide, a known antimicrobial agent. Wettability measurements of samples showed that the introduction of active materials lead to an increase of hydrophilicity, potentially affecting bacterial adhesion.

This contribution describes the recent experimental results obtained at the high voltage (HV) Padova test facility (HVPTF), the laboratory able to carry out HV tests in vacuum up to 800 kVdc/1mA with a holding time of several hours per experimental session and aimed at developing the voltage holding capability of the Megavolt ITer Injector & Concept Advance (MITICA) accelerator, the prototype for the International Thermonuclear Experimental Reactor (ITER) neutral beam injector (NBI). The experiments described in this article refer to a double polarity symmetric configuration, a sphere-to-sphere electrode with an inter-electrode vacuum gap of 30 mm. The results showed that the onset of microdischarges can be ascribed to a mutual exchange of charged particles between specific accumulation points on electrode supports and the vacuum vessel rather than to a direct interaction between the spherical electrodes. The outcome of these experiments is reported and analyzed with both analytical and numerical models.

The High Voltage Padova Test Facility (HVPTF) is an experimental device for investigating HV insulation in vacuum, in support of the realization of MITICA, the prototype of a neutral beam injector for ITER. The facility investigates the physical phenomena underlying voltage holding in vacuum, such as the mechanisms causing breakdowns and the electrode conditioning process, along with testing technical solutions to increase the breakdown threshold. Inside a high vacuum chamber, two stainless steel electrodes, separated by a few centimetres gap, can achieve HV values up to 400 kV each. The conditioning process consists of the gradual increase of the breakdown voltage in time, until the system achieves a saturation value. Between two consecutive breakdown events, current micro-discharges involving the electrodes are observed; high energy X-rays (up to hundreds of keV) and a global increase of gas emission (in particular H2 and CO2 are detected by the Residual Gas Analyser) are measured in correspondence to the current events. Three new Xrays detectors have been recently installed: a small LYSO (4 × 4 × 20 mm3), a LaBr3 (1" x 3/4") and a thin YAP (1"x 2 mm) scintillating crystals, coupled to photomultipliers. They all are small sized scintillators, with very fast pulses (40-100 ns) in order to minimize pile-up effects during the high intensity discharges. However, the high Z and densities guarantee a full energy absorption of the X-rays (they can measure up to 500 keV), with a significant probability, in spite of the small sizes. Energy resolutions are less than 9%. In this contribution we present a characterization of the micro-discharge dynamics occurring during the conditioning phase, focusing on the new details uncovered via the new diagnostics.

This study aims at providing a systematic and critical review on the state of the art of life cycle applications from the circular economy point of view. In particular, the main objective is to understand how researchers adopt life cycle approaches for the measurement of the empirical circular pathways of agri-food systems along with the overall lifespan. To perform the literature review, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol was considered to conduct a review by qualitative synthesis. Specifically, an evaluation matrix has been set up to gather and synthesize research evidence, by classifying papers according to several integrated criteria. The literature search was carried out employing scientific databases. The findings highlight that 52 case studies out of 84 (62% of the total) use stand-alone life cycle assessment (LCA) to evaluate the benefits/impacts of circular economy (CE) strategies. In contrast, only eight studies (9.5%) deal with the life cycle costing (LCC) approach combined with other analyses while no paper deals with the social life cycle assessment (S-LCA) methodology. Global warming potential, eutrophication (for marine, freshwater, and terrestrial ecosystems), human toxicity, and ecotoxicity results are the most common LCA indicators applied. Only a few articles deal with the CE assessment through specific indicators. We argue that experts in life cycle methodologies must strive to adopt some key elements to ensure that the results obtained fit perfectly with the measurements of circularity and that these can even be largely based on a common basis.

This study aims at providing a systematic and critical review on the state-of-the-art of life cycle applications from the circular economy point of view. In particular, the main objective is to un-derstand how researchers adapt life cycle approaches for the measurement of the empirical cir-cular pathways of agri-food systems along the overall lifespan. To perform the literature review, PRISMA protocol was considered to conduct a review by qualitative synthesis. Specifically, an evaluation matrix has been set up to gather and synthesize research evidence, by classifying pa-pers according to several integrated criteria. The literature search was carried out employing scientific databases. Findings evidence that the most common circularity topics are about closed-loop production systems, i.e. nutrient recovery for agricultural purposes, production of renewable energy, valorization of residues and wastes as fertilizers, food waste, and agro-wastes recycling for agriculture. To evaluate the benefits/impacts of CE strategies, Life Cycle Assess-ment (LCA) proved to be the most common methodology applied by authors, as it can help to meet the main CE requirements slowing and closing resource loops.

The High Voltage Padova Test Facilities (HVPTF) is a R&D project focused on understanding the physical processes behind breakdown and micro-discharges in high-voltage insulation, as well as developing new diagnostics, models, and operational modes to address these challenges and aid in the stable operation of MITICA. The X-rays produced during breakdown have a spectrum that extends from low energy (keV) up to several hundreds of keV and a flux that can reach 106 photons/cm2s. This paper shows the development and preliminary results of a newly designed X-Ray diagnostic based on Gas Electron Multiplier (SXR-GEM). This detector is able to stand very high rate (> MHz) in single photon counting mode and can cover the energy range from 3-50 keV. The XR-GEM detector is equipped with anodic pads (256 pads 6x6 mm2) readout with a new data acquisition system called GEMINI, which gives the possibility to obtain a counting rate of several MHz and sub-ms time resolution together with mm spatial resolution. Preliminary measurement shows that this kind of diagnostic is able to reconstruct the time evolution of the discharge at very high rates and to provide X-rays imaging.

To reach fusion conditions and control the plasma configuration in ITER, the next step in tokamak fusion research, two neutral beam injectors (NBIs) will supply 16.5 MW each, by neutralizing accelerated negative hydrogen or deuterium ions. The requirements of ITER NBIs (40A/1 MeV D- ions for ≤1 h, 46A/870 keV H- ions for ≤1000 s) have never been simultaneously attained. So in the Neutral Beam Test Facility (NBTF, Consorzio RFX, Italy) the operation of the full-scale ITER NBI prototype (MITICA) will be tested and optimised up to full performances, focussing on accelerator (including voltage holding), beam optics, neutralisation, residual ion removal. The NBTF includes also the full-scale prototype of the ITER NBI source with 100 keV particle energy (SPIDER), for early investigation of: negative ion production and extraction, source uniformity, negative ion current density and beam optics. This paper will describe the main results of the first two years of SPIDER operation, devoted to characterizing plasma and beam parameters, including investigation of RF-plasma coupling efficiency and magnetic filter field effectiveness in reducing co-extracted electrons. SPIDER is progressing towards the first caesium injection, which aims at increasing the negative ion density. A major shutdown, planned for 2021, to solve the issues identified during the operation and to carry out programmed modifications, will be outlined. The installation of each MITICA power supply and auxiliary system is completed; in-vessel mechanical components are under procurement by Fusion for Energy (F4E). Integration, commissioning and test of the power supplies, procured by F4E and QST, as the Japanese Domestic Agency (JADA), will be presented. In particular, 1.0MV insulating tests were carried out step-by-step and successfully completed. In 2020 integrated tests of the power supplies on the accelerator dummy load started, including the assessment of their resilience to accelerator grid breakdowns using a short-circuit device located in vacuum. The aggressive programme, to validate the NBI design at NBTF and to meet ITER schedule (requiring NBIs in operation in 2032), will be outlined. Unfortunately, in 2020 the coronavirus disease infection affected the NBTF activities. A solution to proceed with integrated power tests despite the coronavirus is presented.

This topical review gathers the last updates concerning caesium-free negative ion sources presented during the $$63{\mathrm {rd}}$$ Course of the International school of Quantum Electronics of the Ettore Majorana Foundation and European collaborative works related to these lectures. Hence, beyond the frame of this course this topical review addresses both theoretical and experimental work performed during these last few years and complexities represented by the conception of a negative ion source ranging from the creation of negative ions to their neutralization.

The reliability of HV insulation across a single gap, in vacuum and low-pressure gas, is known to be a critical issue to be addressed in the development and realization of the electrostatic accelerator for the ITER Neutral Beam Injector (NBI). This paper describes recent experimental results obtained at the High Voltage Padova Test Facility (HVPTF) with the aim of developing an adequate high-voltage insulation system for the MITICA accelerator, the prototype for the ITER NBI. The experiments were carried out on a double-polarity configuration, using sphere-to-sphere electrodes, separated by 30 mm gap. The results showed that the onset of microdischarges is not solely dependent on the cathodic electric field, but also depends on the applied voltage, which determines the energy of the emitted electrons hitting the anode. Furthermore, this phenomenon seems to be dependent on a mutual exchange of charged particles between specific accumulation points on both electrode surfaces. The outcome of these experiments is reported and analyzed with both analytical and numerical models.

Catheter associated urinary tract infection (CAUTI) is a widespread complication within hospitals and nursing homes. A potential treatment is to use a biofilm-inhibiting catheter. In this paper, methods for creating a biofilm retardant catheter coating using silver, silver oxide, and/or zinc particles combined with polydimethylsiloxane (PDMS) are described. The coating was first applied to the outside surface of the catheter and then tested for its antimicrobial properties with respect to preventing planktonic and biofilm growth of Escherichia coli. A comparison of our “in house” created catheters was then made with commercially available antimicrobial urinary catheters.

High voltage (HV) insulation across a single gap in vacuum and low-pressure gas is a critical issue in relation to the development and realization of the electrostatic accelerator for the ITER neutral beam injector (NBI) (Toigo et al 2017 New J. Phys. 19 085004). The present paper describes and analyzes the recent experimental results obtained at the High Voltage Padova Test Facility (HVPTF), the laboratory aimed at supporting the development of the prototype for the ITER NBI (De Lorenzi et al 2011 Fusion Eng. Des. 86 742-5). A voltage up to 800kV(DC) was achieved in the HVPTF during the experimental campaigns with a sphere-plane configurations having variable gap length (from 30 to 150 mm) and pressure ranging from high vacuum (10(-7) mbar) to 10(-3) mbar in argon. Such an experimental campaign represents one of the few examples where voltages higher than 500-550 kV DC are sustained by a single vacuum gap between electrodes (Rohrbach 1971 CERN Report 71-5) and therefore constitutes additional experience to improve the knowledge of voltage holding across large vacuum gaps. The results in high vacuum indicate that at the beginning of voltage conditioning the breakdown events occur at the same cathodic electric field irrespective of the electrode geometry. However, after sufficient conditioning time, the breakdown voltage distribution seems to depend also on the electric field at the anode and on the total voltage between electrodes. A benchmark between a numerical tool previously developed to predict the voltage holding in high vacuum (voltage holding prediction model, VHPM (Pilan et al 2011 Fusion Eng. Des. 86 742-5)) and the experimental results is also reported and discussed.

Of Mediterranean countries, Italy represents the second largest producer of olive oil, with about 14% of total world production, and represents the largest consumer worldwide, with 20.8% of total world consumption. Olive cultivation is mostly confined to southern regions, which overall account for about 80% of national olive oil production. In Calabria, olive growing plays a significant economic role, particularly in rural contexts, although olive growers have to face different problems such as high production costs, low productivity and low levels of mechanization of agricultural practices. However, many olive farms produce high-quality olive oil, thanks to both more efficient farming management and the adoption of product and process innovations. This paper aims to assess the long-term feasibility of different olive-growing systems in the Calabrian region (southern Italy) by means of joint use of a life cycle costing (LCC) approach and dynamic evaluation methods. The economic analysis allowed us to recognize the main hotspots within the product life of each system analyzed, useful to identify potential enhancements to the production process and to give rise to greater levels of profitability. Our results highlighted a suitable level of economic viability for almost all systems investigated, in particular when public subsidies from the European Union were considered. Our research could be useful to suggest the adoption of possible improvement strategies for corporate decision-making processes, to achieve appropriate economic sustainability performance.

Catheter acquired urinary tract infection (CAUTI) is a significant problem in the medical community. Interdisciplinary teams have coordinated to address this problem, yet there is still a need for an adequate solution. In this study, we investigate an electricidal solution by adopting electrochemically active materials that can be incorporated into a urinary catheter. Zinc and silver oxide powders deposited in the form of patterned electrodes on a thermoplastic substrate are shown to illustrate electricidal properties in urine, including the ability to produce electric fields, pH increases, as well as, formation of hydrogen peroxide. The newly developed samples show promising results for killing planktonic E. coli in a controlled setting.

Heating neutral beam (HNB) injectors, necessary to achieve burning conditions and to control plasma instabilities in ITER, are characterized by such demanding parameters that a neutral beam test facility (NBTF) dedicated to their development and optimization is being realized in Padua (Italy) with direct contributions from the Italian government (through Consorzio RFX as the host entity) and the ITER international organization (with kind contributions from the ITER domestic agencies of Europe, Japan and India) and technical and scientific support from various European laboratories and universities. The NBTF hosts two experiments: SPIDER, devoted to ion source optimization for the required source performance, and MITICA, the full-size prototype of the ITER HNB, with an ion source identical to SPIDER. This paper gives an overview of the progress towards NBTF realization, with particular emphasis on issues discovered during this phase of activity and on solutions adopted to minimize the impact on the schedule and maintain the goals of the facilities. The realization of MITICA is well advanced; operation is expected to start in 2023 due to the long procurement time of the in-vessel mechanical components. The beam source power supplies, operating at 1 MV, are in an advanced phase of realization; all high-voltage components have been installed and the complex insulation test phase began in 2018. At the same time, construction and installation of SPIDER plant systems was successfully completed with their integration into the facility. The mechanical components of the SPIDER ion source were installed inside the vessel and connected to the plants. Integrated commissioning with the control, protection and safety systems ended positively and the first experimental phase has begun. The first results of the SPIDER experiment, with data from operational diagnostics, and the plans for the 1 MV insulation tests on the MITICA high-voltage components are presented.

The aim of the present randomized controlled clinical trial was to compare the use of donkey milk-derived fortifier (DF) with commercial bovine milk-derived fortifier (BF) in very preterm or very low-birth-weight newborns, in terms of feeding tolerance. The trial included 156 newborns born at

Jarosite is a dangerous waste derived from the hydrometallurgical route of zinc production, and it cannot be safely disposed of due to its acidic pH and the risk of toxic metal leaching. A new process at laboratory scale for the utilization of jarosite sludges is proposed, with the aim to obtain cast iron and an inert slag, using blast furnace sludges as reducing agent. Jarosite-reducing agent mixes were reduced in a muffle furnace at 1500 °C for 15 min. Two reducing agents were used: pure graphite (as control) and blast furnace sludges. Two CaO concentrations (5, 15%wt. on jarosite mass) and four equivalent C concentrations (7.5, 15, 30, 60%wt. on jarosite mass) were analysed. Cast iron was obtained from all of the mixes, but the highest reduction yield was obtained at 15%wt. equivalent C. The slag obtained from the control batch had a fully crystalline structure, while the one related to the sample with BF sludges showed an incipient vitrified structure, that could prevent the leaching of hazardous elements. The best process parameters to profitably obtain cast iron and a glassy slag are 15% of equivalent C, 5% CaO and blast furnace sludges as reducing agent.

Objectives Evaluation of the reliability and the validity of the Italian version of the Bus Story Test (I-BST), providing normative data in Italian children. Methods A total of 552 normally developing children (278 males and 274 females) aged 3; 6 to 9; 0 years, were enrolled. Test-retest, intra- and inter-rater reliability were analysed on a sample of respectively 145, 178 and 178 children. Normative data were gathered from all the enrolled children and estimate centiles according to the CG-LMS method provided. The children were divided into 11 age classes of six months each; percentile scores and standard error measurement were analysed in children from age class 4; 0-4; 5 years to age class 8; 6-811 years. Age effects on I-BST were analysed. Results Results showed high test-retest, intra- and inter-rater reliability scores. A significant age effect on I-BST scores emerged from the ANOVA test analysis; in particular, as age increases, so do I-BST scores. Conclusion The I-BST is a reliable and valid tool. The availability of normative data for Italian speaking children may help clinicians during clinical assessment.

At high de voltage (>100 kV) and with long gap (>10−3m) (p

The contact potential across the head-disk interface is investigated. AC voltage was applied to the disk surface using a mercury connector located at the top of the spindle, keeping the recording head grounded. The acoustic emission (AE) and touchdown sensor (TDS) amplitude was measured as a function of the DC offset voltage to determine the contact potential across the head-disk interface at which the AE and TDS signals, respectively, becomes a minimum. The contact potential across the head-disk interface is studied as a function of temperature, relative humidity, and wear of the head-disk interface.

Localized heating has been observed in unexpected positions on anodic surfaces in a multi-electrode device insulated by vacuum gaps. In double polarity experiments, a counter-intuitive behavior of current-voltage characteristic has also been observed. The phenomena could depend on a cascade effect of charged particles exchanged between electrodes and on a mutual correlation of particle trajectories between electrode surfaces occurring during the high voltage conditioning phase. Attractors regions ascribed to regenerative processes of charged particles between cathode and anode have been identi fi ed thanks to numerical simulations The position of the attractors depends only on electrode shape and the ratios of applied voltages. This fi nding suggests new perspectives in neutrons sources applications, where recurrent impacts of focused high energy hydrogen isotopes take place on solid hydride targets supported by metallic electrodes insulated by vacuum gaps.

High Voltage Padova Test Facility (HVPTF) is an experimental device realized to investigate the in vacuum high voltage insulation aspects in support of MITICA, the neutral beam injector prototype for ITER. Moreover, the experiment aims to give a contribution on the understanding of the voltage holding in vacuum, as a physical phenomenon. The two stainless steel electrodes, with few cms of gap in a high vacuum chamber, achieve a saturation breakdown value after about ten hours. A highly time resolved X-rays diagnostic has been recently installed in the device, measuring the X events (single events are detected) produced during the high voltage (up to 400 kV) conditioning: high energy peaks are observed in correspondence to the current peaks collected by the electrodes. This contribution presents a characterization of the current and the X-rays events in terms of frequency, amplitude and their occurrence with respect to the tension between the electrodes.

We evaluated the influence of Daphnia grazing on water clarity in Onondaga Lake, New York, by testing 2 related hypotheses: (1) that the high clarity (Secchi disk depth [SD]) events observed in 18 years of a 27-year record were occurrences of the clear water phase (CWP) associated with elevated levels of Daphnia grazing, and (2) that reductions in minerogenic (i.e., inorganic) particle concentrations and the accompanying reductions in light scattering (quantified by b m ) due to grazing contributed importantly to the SD signatures of the CWPs. Our analysis is based on a 27-year record of the Daphnia population, SD, and the concentration of chlorophyll a (Chl- a ), as well as shorter-term characterizations of minerogenic particle concentrations in the lake and application of an optical theory-based SD model previously tested for the lake. The first hypothesis is supported by (a) the consistency of seasonal patterns of Chl- a , SD, and Daphnia biomass, (b) the consistency of Daphnia biomass maxima with literature values associated with the CWP, (c) the positive relationships demonstrated between interannual differences in Daphnia biomass (and estimated grazing rates) and peak SD and duration of high clarity events, and (d) because during CWPs, estimated grazing rates exceed by a wide margin reasonable maximum values of phytoplankton growth rates. The second hypothesis is supported by (a) demonstration that the minerogenic particle sizes responsible for b m (and so its influence on SD) are within the size range subject to Daphnia grazing, and (b) application of the SD model, in the context of SD and Chl- a observations, showing that a reduction in b m is necessary to explain the high SD values observed during CWPs. Finally, a review of the growing literature on the contribution of b m to the overall particle scattering coefficient in various lakes suggests that minerogenic particles are often important to the SD signature of CWPs.

In this investigation, we examine wear of thermal flying height control sliders as a function of DC bias voltage across the head–disk interface, relative humidity, and lubricant type. Wear tests were conducted using two different experimental setups, a load/unload tester, and a spin-stand tester with relative humidity control. Head wear was determined by measuring the change in the heater touch-down power (ΔTDP) before and after wear testing. After wear testing, selected recording heads were examined using atomic force microscopy and time of flight secondary ion mass spectrometry to investigate wear and deposit formation in the read/write region. Our results show that the polarity of the head–disk interface bias voltage and the relative humidity influence deposit formation and wear in the read/write region of recording heads.

SPIDER is one of two projects of the ITER Neutral Beam Test Facility under construction in Padova, Italy, at the Consorzio RFX premises. It will have a 100 keV beam source with a full-size prototype of the radiofrequency ion source for the ITER neutral beam injector (NBI) and also, similar to the ITER diagnostic neutral beam, it is designed to operate with a pulse length of up to 3600 s, featuring an ITER-like magnetic filter field configuration (for high extraction of negative ions) and caesium oven (for high production of negative ions) layout as well as a wide set of diagnostics. These features will allow a reproduction of the ion source operation in ITER, which cannot be done in any other existing test facility. SPIDER realization is well advanced and the first operation is expected at the beginning of 2018, with the mission of achieving the ITER heating and diagnostic NBI ion source requirements and of improving its performance in terms of reliability and availability. This paper mainly focuses on the preparation of the first SPIDER operations - integration and testing of SPIDER components, completion and implementation of diagnostics and control and formulation of operation and research plan, based on a staged strategy

The ITER Neutral Beam Test Facility (NBTF), called PRIMA (Padova Research on ITER Megavolt Accelerator), is hosted in Padova, Italy and includes two experiments: MITICA, the full-scale prototype of the ITER heating neutral beam injector, and SPIDER, the full-size radio frequency negative-ions source. The NBTF realization and the exploitation of SPIDER and MITICA have been recognized as necessary to make the future operation of the ITER heating neutral beam injectors efficient and reliable, fundamental to the achievement of thermonuclear-relevant plasma parameters in ITER. This paper reports on design and R&D carried out to construct PRIMA, SPIDER and MITICA, and highlights the huge progress made in just a few years, from the signature of the agreement for the NBTF realization in 2011, up to now - when the buildings and relevant infrastructures have been completed, SPIDER is entering the integrated commissioning phase and the procurements of several MITICA components are at a well advanced stage

The realization of the ITER Neutral Beam Test Facility (NBTF) and the start the experimental phase are important tasks of the fusion roadmap, since the target requirements of injecting to the plasma a beam of Deuterium atoms with a power up to 16.5 MW, at 1MeV of energy and with a pulse length up to 3600s have never been reached together before. The ITER NBTF, called PRIMA (Padova Research on ITER Megavolt Accelerator), is hosted in Padova, Italy; it includes two experiments: MITICA, the full-scale prototype of the ITER injector and SPIDER, the full-size negative ion source. The realization promoted by the ITER organization is carried out with the contribution of the European Union, channeled through the Joint Undertaking for ITER (F4E), of the Consorzio RFX which hosts the Test Facility, the Japanese and the Indian ITER Domestic Agencies (JADA and INDA) and several European laboratories, such as IPP-Garching, KIT-Karlsruhe, CCFECulham, CEA-Cadarache. The early start of operation of PRIMA experiments is urgent because sufficient experimental time is necessary to face and solve the issues related to the achievement of the desired performance in time for the ITER operation, requiring NBI since the beginning. Substantial progresses have been recently achieved: the buildings construction, begun in October 2012, has been completed by the end of 2015 and the installation of some components has been started since the end of 2014. The SPIDER realization is well advanced: the installation phase is proceeding in good agreement with the general plan; it is expected to be almost completed by the end of 2016. In parallel, the commissioning of the SPIDER power supply (PS) and auxiliary plant systems is being proceeding. Tests at full power and remote control are planned, including also those addressed to reproduce the grid breakdowns and to test the relevant protections. The design of the MITICA injector components was completed in 2015their procurement is being made through a number of tenders, some of them already launched. The HV Power Supply system of the MITICA 1MV accelerator, provided by JADA, was delivered on site in December 2015. The challenging installation of these components, including the step-up transformers and the SF6 gas insulated transmission line, started soon after and will go on throughout 2016. The present phase, with the PRIMA buildings continuously filled with new components, with the installation activities progressing and with also the commissioning and testing phase starting represents a substantial step forward toward the main target. The paper will describe the main challenges the Project Team has dealt during this phase and the important feedback derived for the ITER HNB systems both from the technical and the organizational standpoints.

In the framework of the program for the construction-in Padova, Italy-of the first prototype of the International Thermonuclear Experimental Reactor 1 MeV-16 MW negative neutral beam injector (NNBI), an R&D activity on voltage holding in vacuum has been initiated since 2009, aimed at supporting the design, construction, and development of the NNBI accelerator. For this purpose, the high-voltage Padova test facility, designed to operate up to 800 kV, has been built, in parallel to the development of a multivoltage multielectrode voltage holding prediction model (VHPM). This paper focuses on the results of the experimental campaign (up to 270 kV) carried out on a number of electrostatic configurations, aimed at validating the VHPM under a well-controlled condition. The prediction capability of the model is partially confirmed. This result makes it worthwhile to review the physical basis of the model-based on the Cranberg-Slivkov clump theory-while also taking into consideration an alternative breakdown initiation mechanism.

Zebra mussels have invaded many lakes in the United States and could be a useful tool for monitoring responses of aquatic biota to changes in mercury loading. The goal of the present study was to evaluate zebra mussels for use as a biomonitor of mercury contamination by comparing zebra mussel mercury concentrations between a lake with only indirect atmospheric mercury contamination (Otisco Lake, NY, USA) and a lake that was directly contaminated by mercury discharges (Onondaga Lake, NY, USA). Zebra mussels were sampled in both the spring and fall of 2004 and 2005. Total mercury (THg) concentrations in zebra mussels were approximately seven times greater in Onondaga Lake than in Otisco Lake, and water column mercury concentrations differed by an order of magnitude between the two lakes. Seasonal differences resulted in significantly higher zebra mussel THg concentrations during the fall for both lakes. There was also significant variation among different sampling sites in Onondaga Lake. Mussel methylmercury concentrations averaged 53% of THg concentrations but were highly variable. Strong relationships between water column THg and zebra mussel THg suggest that zebra mussels are a good indicator of aquatic mercury concentrations and could be used as an effective biomonitor of mercury contamination in aquatic ecosystems. Environ. Toxicol. Chem. 2013;32:638–643. © 2012 SETAC

The effect of slider bias voltage and humidity on wear at the head/disk interface is investigated. Wear of thermal flying height control sliders is studied as a function of head/disk bias voltage, relative humidity, and heater power. The electrostatic force and the contact potential at the head/disk interface is monitored before and after head wear using the noncontact Kelvin probe method.

This paper reports the main results of the RFX-mod fusion science activity since the last 2014 IAEA Fusion Energy Conference. The RFX-mod device is characterized by a unique flexibility in terms of accessible magnetic configurations. Axisymmetric and helically shaped Reversed-field pinch equilibria have been studied, along with tokamak plasmas in a wide range of q(a) regimes (spanning from 4 down to 1.2 values). The full range of magnetic configurations in between the two, the so-called ultra low-q ones, has been explored, with the aim of studying specific physical issues common to all equilibria, such as, for example, the density limit phenomenon. The powerful RFX-mod feedback control system has been exploited for MHD control, which allowed to extend the range of experimental parameters, as well as to induce specific magnetic perturbations for the study of 3D effects. In particular, transport, edge and isotope effect in 3D equilibria have been investigated, along with runaway mitigations through induced magnetic perturbations. The first transitions to H-mode in circular and D-shaped tokamak plasmas have been obtained thanks to an active modification of the edge electric field through a polarized electrode. The experiments are supported by intense modelling with 3D MHD, gyrokinetic, guiding center and transport codes. Proposed modifications to the RFX-mod device, which will enable further contributions to the solution of key issues in the roadmap to ITER and DEMO, are also briefly presented.

The modified RFX is a very flexible device used for a variety of control schemes for MHD instabilities and for advanced reverse field pinch scenarios. Relative to the previous machine, RFX-mod has a thin Cu shell with vertical field penetration time τS, lowered from 450 to 50 ms and shell/plasma proximity from b/a ≤ 1.24-1.1. Toroidal equilibrium is feedback-controlled and new power supplies provide better Bφ control. Newly designed graphite tiles protect the vessel from localized power deposition. A mesh of 192 external saddle coils, supervised by a digital feedback system, controls radial fields due to field errors and MHD modes. The paper presents an overview of the very encouraging results obtained using both new and 'standard' advanced operational modes in the current range 0.3-1 MA. A dramatic improvement of plasma performance was obtained by using the saddle coils to cancel all the radial field components, an operation mode dubbed virtual shell (VS). The toroidal voltage was lowered by more than 25% and the pulse length was tripled, up to 7 times the τS. Steady-state RFP pulses are now limited only by the applied volt-seconds. The improved magnetic boundary also has an effect on the tearing modes underlying the sustainment of the RFP, whose core amplitude is more than halved. The VS combined with new schemes for the active rotation of the MHD dynamo modes has allowed us to obtain reliable and well-controlled long RFP pulses in the MA current range. This results in a 100% increase in the particle and energy confinement time relative to the previous experiment and opens the possibility of exploring the machine performance in the 2 MA design range. © 2007 IAEA.

In Calabria Region (Southern Italy), the province of Cosenza represents an important area for figs growing belonging to cultivar 'Dottato' that is used to produce the quality-branded dried figs “Fichi di Cosenza” PDO (protected designation of origin). In the last years, due to a significant increase of dried figs consumption, a growth of public subsidies aimed to introduce innovative practices in figs orchards has occurred. The present paper aims to evaluate the economic sustainability of investments in fig tree farms, by integrating life cycle costing (LCC) methodology with specific economic indicators. Furthermore, a comparison between fig orchards and other local and profitable permanent crops has been carried out, on the basis of all economic results. The analysis allowed to account for all costs during the whole lifetime of investments, by rationalizing the corporate decision-making process for the choice between different alternatives. Results showed the economic viability of 'Dottato' fig investments and a suitable level of profitability. In this context, figs production could represent an important small-scale agro-food supply chain useful to the improvement of rural economy and to enhancement of local quality food.

The interplay between sheared E x B flows and turbulence has been experimentally investigated in the edge region of the Extrap-T2R reversed field pinch experiment. Electrostatic fluctuations are found to rule the momentum balance equation representing the main driving term for sheared flows which counterbalances anomalous viscous damping. The driving role of electrostatic fluctuations is proved by the spatial structure of the Reynolds stress and by the time behaviour of the mean energy production term which supports the existence of an energy exchange from the small scales of turbulence to the larger scales of the mean flow.

The results leading to the identification of coherent structures emerging from the background turbulence in the edge region of the reversed field pinch experiments EXTRAP-T2R and RFX are reviewed. These structures have traits of vortices in velocity field and blobs in density, and the reconstruction of their spatial structure and of their time evolution is discussed focusing on the analysis tools applied. The role of these structures in the particle anomalous transport is addressed, showing that their collisions can contribute up to 50% the total particle losses.This process is shown to be responsible for bursts in particle flux and it is found to set a characteristic collision time, which is in agreement with the statistical properties of laminar times for particle flux bursts. © 2006 The Royal Swedish Academy of Sciences.

Coherent structures emerging from the background turbulence have been detected by electrostatic measurements in the edge region of two Reversed Field Pinch experiments, RFX (Padua) and Extrap-T2R (Stockholm). Measurements have been performed by arrays of Langmuir probes which allowed simultaneous measurements of temperature, potential and density to be carried out. These structures have been interpreted as a dynamic balance of dipolar and monopolar vortices, whose relative population are found to depend on the local mean E × B flow shear. The contribution to the anomalous transport of these structures has been investigated and it has been found that the corresponding diffusion coeffcient accounts up to 50% of the total diffusivity. The experimental findings indicate that the diffusion coeffcient associated to the coherent structures depends on the relative population of the two types of vortices and is minimum when the two populations are equal. An interpretative model is proposed to explain this feature.