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Few population studies are available on epidemiological indexes of hereditary ataxias. An investigation on the prevalence rate of these movement disorders is in progress for the Veneto region, the main area of northeast Italy with a population of 4,490,586 inhabitants. The first results of this epidemiological survey concern the province of Padua, which numbers 845,203 residents (January 1, 2002). The prevalence rate of inherited ataxias has been estimated at 93.3 cases per million inhabitants. The most common types appeared to be the autosomal dominant forms, namely spinocerebellar ataxia type 1 and 2, with a prevalence of 24 per 1,000,000. In the same population, with a prevalence rate of 6 per 1,000,000, Friedreich's ataxia was defined as the prominent recessive autosomal form. There were very rare cases of ataxia telangiectasia, ataxia with vitamin E deficiency and cerebellar ataxia with congenital muscular dystrophy, a recently identified autosomal recessive disease. [ABSTRACT FROM AUTHOR]

Copyright of Santo: Rivista Francescana di Storia Dottrina Arte is the property of Associazione Centro Studi Antoniani and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Santo: Rivista Francescana di Storia Dottrina Arte is the property of Associazione Centro Studi Antoniani and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingegneria Ferroviaria is the property of Ingegneri Ferroviari and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The construction of MITICA, the full-size prototype of the ITER Heating Neutral Beam Injectors (HNBs) is in progress at the Neutral Beam Test Facility (NBTF) located in Padova, Italy. The design of the central control (CODAS) and interlock (CIS) systems is progressing taking into account the requirements coming from the MITICA plant units, in terms of number and type of interface signals, data sampling frequency values, operating states, protection actions and required reaction times and reliability. As the HNBs will be ITER components, additional requirements derive from the ITER plant control design handbook that specifies the design criteria and standard technologies to be applied to ITER plant systems. A distinction must be made in MITICA between plant units that will be part of the HNB, such as the power supply systems, and plant units that are auxiliaries, such as the gas and vacuum system. In the NBTF these components shall interface with MITICA CODAS and CIS, whereas in ITER they will be autonomous plant systems providing services to the HNB. The distinction reported above suggests defining the architecture of MITICA Instrumentation and Control (I&C) as split into the following functional blocks: i) HNB plant system including components that will be part of the HNB; ii) Service plant system including all operational plant units that need control in the NBTF but are implemented outside the ITER HNB; iii) Diagnostics plant system; iv) Central I&C (CODAS and CIS). The paper presents the requirements for MITICA CODAS and CIS and derives from these the system architecture. The design of CODAS and CIS is discussed with reference to the lesson learned in the implementation of SPIDER CODAS and CIS (the NBTF ion source test bed) and to the technologies suitable for the implementation. [ABSTRACT FROM AUTHOR]

The ITER Neutral Beam Test Facility (NBTF) is currently under construction at Consorzio RFX, Padova, Italy. The NBTF includes two experimental devices: SPIDER for the study of the ion source and MITICA for the development of the full-size HNB prototype. Even if the two experiments share many architectural aspects in their Control and Data Acquisition System (CODAS), there are nevertheless some significant differences because MITICA must adhere to ITER's directives for plant control design. This paper describes the architecture of the MITICA timing system that represents one of the first examples of integration of IEEE1588 timing functions in fusion research medium-scale experiments. [ABSTRACT FROM AUTHOR]

The ITER Heating Neutral Beam (HNB) source prototype SPIDER (Source for the Production of Ions of Deuterium Extracted from a Radio frequency plasma), hosted at the Neutral Beam Test Facility (NBTF) in Padova, Italy, has recently started operating with evaporated caesium in the source. This moves the primary H − production mechanism from volume to surface processes, increasing the extracted H − current while decreasing the co-extracted electron current. As in volume operation, the beam exhibits inhomogeneities across the vertical profile due to magnetic drifts, a result of the transverse filter field, which is vital for reducing the electron temperature near the extraction region. To minimise the occurrence of electrical discharges, SPIDER has been operated with a diminished number of extraction apertures to minimise the vessel pressure/ion source pressure ratio by means of a mask, which reduces the gas flow conductance between the source and the vessel. Therefore, it has been possible to directly measure the current of individual beamlets, due to the increased room between the beamlets, using the non-invasive Beamlet Current Monitor (BCM) diagnostic. Using measurements of five individual beamlets the homogeneity of the SPIDER H − beam has been assessed, in a range of operating conditions with caesium in the source. The dependence of the beam homogeneity on source parameters (bias, filter field, RF power) has been observed, while increasing the Cs evaporation rate and unbalancing the power of the RF generators have proven to be effective at mitigating the beam inhomogeneity. • Direct measurement of the accelerated current of five SPIDER beamlets. • Observation of beam current non-uniformity on the beamlet scale. • Effect of electrode biasing on the vertical beam current uniformity. • Comparison to beamlet current calculated from IR calorimetry. [ABSTRACT FROM AUTHOR]

• The insulation capability of a full silica kapton coated optical fiber in vacuum under DC voltage is about 160kV for 600mm length. • The commercial batteries providing the highest energy density for low power application are Li-SOCl2 battery • The PIC microcontroller proven to be a reliable device with respect to EMI irradiated from Surge pulses as well as it can be a very low power consumption ADC when the IDLE and Standby operational modes are exploited. • A solution to feed electronic devices operating at high voltage in harsh environments (vacuum, risk of discharges, x rays in the nearby,...) in a reliable way consists in enclosing the batteries in a vacuum tight commercial nipple closed by a dedicated feedthrough. • The precise synchronization of fast events within a system of distributed devices can be done with a distributed trigger network when a deterministic time delay is known. The trigger time can be also precisely time stamped by means of a fast transient FPGA recorder provided by a iW-RainboW-G36S board that is kept in sync with a GPS absolute time source with IEEE1588 protocol. ITER is an experimental fusion device and requires two Neutral Beam Injectors (NBIs) for plasma heating and current drive which have to supply a power of 16.5 MW each, delivered by a 1MeV deuterium beam. This D0 beam is generated starting from negative ions, produced inside a RF driven ion source, and accelerated by a Multi-Aperture Multi-Grid electrostatic accelerator insulated in vacuum. MITICA (Megavolt ITER Injector & Concept Advancement) is a full-scale prototype of the ITER Heating Neutral Beams (HNBs), devoted to test and optimize the design, under construction in Padova at the Neutral Beam Test Facility (NBTF) hosted by the Consorzio RFX. One of the most critical requirements in MITICA concerns the capability to withstand the nominal voltage of 1MV on a single long gap (≈1m), which separates the beam source and the vacuum vessel, insulated by vacuum or low pressure gas (10−6-10−3 mbar range) and with large size electrodes. In order to address this issue, a dedicated experimental test campaign exploiting a 1:1 mockup of the MITICA Beam Source will be carried out at NBTF before the installation of the actual Beam Source. During this test campaign, a set of electrical diagnostics will be installed to identify the location of the breakdowns as well as to measure the magnitude of the microdischarge currents (the precursors of vacuum breakdowns), and arc currents to provide useful information to optimize the electrostatic design of the ITER HNB and to validate the numerical models. This paper describes the development and the design of these diagnostics system based on electrical measurements. [ABSTRACT FROM AUTHOR]

• Data streaming implementation and optimization techniques. • Distributed data access for long lasting experiments. • Large signals storage and retrieval tehcniques. The SPIDER experiment is the first of two experiments being held at the ITER Neutral Beam Test Facility in Padova (Italy). SPIDER has been operating since 2018, initially with pulse duration of a few seconds and currently with pulses lasting up to 3000 s. The paper reports the CODAS experience gained after three years of operation. In particular, Data Storage and Data Access adopted strategies will be discussed, that proved to be of high impact in overall system performance and maintainability. Regarding Data Storage strategy, a tradeoff must be defined between the continuous and event driven data acquisition. Continuous data acquisition, i.e. sampling data at a constant frequency, represents the normal operation in short experiments, but can easily lead to an unmanageable amount of data for long lasting experiments. On the other side, Data acquisition at a varying rate, that is increased upon the occurrence of given events leading to an improved signal dynamics, is required for a subset of signals that describe physical phenomena with fast dynamics. Several strategies have been adopted in SPIDER to handle varying rate data acquisition and are discussed here. Considering data access strategy, an important Use Case, especially when the pulse duration is long, is the concurrent access to the pulse file for online analysis and visualization. Concurrent data read and write is supported by MDSplus, the adopted data system, but performance can be affected by the required locks in file access. For this reason it is important to limit as far as possible useless data access. This has been achieved in different ways, such as setting a Region of Interest (ROI) in data access and by the extended usage of on-the-fly resampling in conjunction with the availability in the pulse file of different versions of the same data item, acquired at different sampling speeds. [ABSTRACT FROM AUTHOR]

SPIDER is the full scale prototype for the ITER Heating Neutral Beam source, hosted at the Neutral Beam Test Facility in Padova, Italy. The behavior of the beam must be thoroughly investigated to bring the machine's performance in line with ITER's requirements. In particular, ripples in the beam can affect its divergence. Measuring the AC component of the beam current can therefore help to understand the impact that the oscillations caused by the source power supplies or RF generators have on the beam optics. To minimize the occurrence of electrical discharges, SPIDER was recently operated with a mask designed to close a large number of extraction apertures. As a consequence, the space between each beamlet was substantially increased, allowing for the installation of the Beamlet Current Monitor (BCM) which enables a non-invasive direct measurement of the DC and AC components of the currents of 5 individual beamlets. A first assessment of the beamlet currents' AC components (up to 10 MHz) was performed during SPIDER's first campaign with cesium evaporation. Recurring oscillations were identified in various frequency ranges, with amplitudes reaching up to ∼ 7% of the beamlet current DC value. When possible, the ripples were correlated to oscillations due to the RF oscillators and the beatings caused by their mutual coupling, or to SPIDER's power supply systems. • The AC component of the ion beam in SPIDER was characterized with the BCM diagnostic. • The beam features ripples due to the RF oscillators and their beatings. • Power supply oscillations at multiples of 50 Hz are seen in the plasma and the beam. • A 138.8 kHz ripple caused by the EG power supply can reach very large amplitudes. [ABSTRACT FROM AUTHOR]