Design of a plasma discharge circuit for particle wakefield acceleration

Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (10–100 GV m 1), enabling acceleration of electrons to GeV energy in few centimetres. However, the quality of the electron bunches accelerated with this technique is still not comparable with that of conventional accelerators; radiofrequency-based accelerators, in fact, are limited in the accelerating field (10–100 MV m 1) requiring therefore kilometric distances to reach the GeV energies, but can provide very bright electron bunches. Combining high brightness electron bunches from conventional accelerators and high accelerating fields reachable with plasmas could be a good compromise allowing to further accelerate high brightness electron bunches coming from LINAC while preserving electron beam quality. Following the idea of plasma wave resonant excitation driven by a train of short bunches, we have started to study the requirements in terms of plasma for SPARC-LAB [1,2]. In particular, here we focus on the ionization process; we show a simplified model to study the evolution of plasma induced by discharge, very useful to design the discharge circuit able to fully ionize the gas and bring the plasma at the needed temperature and density

Design, Realization, and Test of Ultraviolet-C LED Arrays Suitable for Long-Lasting Irradiation of Biological Samples

We present the electrical and optical design, assembling, and thorough experimental characterization of two compact arrays of short-wavelength ultraviolet (UV-C) light-emitting di-odes (LEDs) suitable for near-field irradiation. Through a combination of technical expedients, we have achieved effective thermal management such that long-lasting irradiations are possible without appreciable deterioration of UV-C emission. We successfully used these compact UV-C LED arrays for long lasting irradiation tests aimed at generating the biosynthesis of defensive metabolites that enhance the resistance of plants and fruits to pathogen attacks. Finally, we comment on the possibility of implementing these compact UV-C sources on robotic systems to make an automated device suitable to reduce pesticide use in agricultural crops

IL-18 receptor marks functional CD8+ T cells in non-small cell lung cancer

IL-18 is an inflammasome-related cytokine, member of the IL-1 family, produced by a wide range of cells in response to signals by several pathogen-or damage-associated molecular patterns. It can be highly represented in tumor patients, but its relevance in human cancer development is not clear. In this study, we provide evidence that IL-18 is principally expressed in tumor cells and, in concert with other conventional Th1 cell-driven cytokines, has a pivotal role in establishing a pro-inflammatory milieu in the tumor microenvironment of human non-small cell lung cancer (NSCLC). Interestingly, the analysis of tumor-infiltrating CD8(+) T cell populations showed that (i) the relative IL-18 receptor (IL-18R) is significantly more expressed by the minority of cells with a functional phenotype (T-bet(+)Eomes(+)), than by the majority of those with the dysfunctional phenotype T-bet(+)Eomes(+) generally resident within tumors; (ii) as a consequence, the former are significantly more responsive than the latter to IL-18 stimulus in terms of IFN gamma production ex vivo; (iii) PD-1 expression does not discriminate these two populations. These data indicate that IL-18R may represent a biomarker of the minority of functional tumor-infiltrating CD8(+) T cells in adenocarcinoma NSCLC patients. In addition, our results lead to envisage the possible therapeutic usage of IL-18 in NSCLC, even in combination with other checkpoint inhibitor approaches

Progettazione, realizzazione e test sperimentali di un illuminatore a LED UV-C

Le lunghezze d’onda comprese tra 200 e 280 nanometri, intervallo spettrale denominato UV-C, sono particolarmente adatte a debellare batteri e virus in quanto tale radiazione spezza i legami proteici e può danneggiare in modo irreversibile le catene del DNA/RNA. Sino a poco tempo fa, le sorgenti UV-C disponibili in commercio erano lampade a gas, basate tipicamente su deuterio, xenon, vapori di mercurio, o eccimeri. Queste lampade funzionano a tensioni piuttosto elevate, sono fragili e hanno tempi di accensione di diversi minuti prima di arrivare a regime ed emettere la potenza nominale. La disponibilità di LED (Light Emitting Diodes, dispositivi a stato solido) che emettono radiazione nell’intervallo dell’UV-C consente oggi di realizzare una “lampada”, basata su una matrice di tali sorgenti, che utilizza un alimentatore a bassa tensione, può essere disegnata in configurazioni geometriche adattabili ad ogni esigenza, si accende istantaneamente ed è meccanicamente molto robusta. In questo Rapporto Tecnico sono illustrati il progetto, la realizzazione e la caratterizzazione di una lampada a LED UV-C e del relativo alimentatore. È inoltre brevemente descritto un esperimento, a scopo fitosanitario, in cui tale lampada è stata utilizzata.Optical radiation with wavelengths between 200 and 280 nanometers, in the UV-C range, is particularly suitable for eradicating bacteria and viruses, as this radiation breaks protein bonds and can irreversibly damage DNA/RNA chains. Until recently, the commercial UV-C sources were gas lamps, typically based on deuterium, xenon, mercury vapor, or excimers. All of these lamps operate at quite high voltages, are fragile and require several minutes of warming up before working at full power. The availability of solid-state LEDs (Light Emitting Diodes) that emit radiation in the UV-C range allows a “lamp” to be made by assembling an array of such light sources, which uses a low-voltage power supply, can be designed in geometric configurations adaptable to any need, turns on/off instantly and is robust. This Technical Report illustrates the work done at ENEA Frascati on the design and assembly of a UVC LED lamp and of its power supply, its characterization and application to a phytosanitary experiment

La bussola solare ENEA in archeoastronomia. Rilievi di orientamento nella grotta di Tiberio a Sperlonga

La bussola solare elettronica brevettata da ENEA è uno strumento compatto, automatico, accurato (risoluzione migliore di un primo d’arco, pari a 0,016 gradi) e veloce (fornisce l’orientamento in pochi secondi). La bussola ENEA è stata già usata con successo per rilevamenti di orientamento in Antartide (in collaborazione con INGV), per il controllo della movimentazione e dell’orientamento dell’asse di rotazione degli specchi delle centrali solari a concentrazione (in collaborazione con D.D. s.r.l.), e per la progettazione di meridiane. In questo rapporto presentiamo l’uso della bussola ENEA nelle misure di orientamento di alcune strutture della Grotta di Tiberio adiacente alla Villa appartenuta nel I secolo d.C. all’imperatore romano Tiberio, presso l’area annessa al Museo Archeologico Nazionale di Sperlonga, in provincia di Latina. Le misure di orientamento sono finalizzate a verificare se tali strutture presentino una direzione privilegiata rispetto a particolari eventi astronomici, collegati al moto apparente del Sole.The Electronic solar compass, patented by ENEA, is compact, automatic, accurate (the orientation/azimuth is determined with a resolution better than 0.016°), and fast (it provides the orientation in few seconds). The ENEA compass has been successfully used for orientation measurements in Antarctica (in collaboration with INGV), for handling the movement and checking the rotation axis orientation of the mirrors in the concentrated solar power plants (in collaboration with D.D. srl,), and for the design of sundials. In this report, we exploit the ENEA solar compass in archeoastronomy, specifically in orientation measurements of some structures at the Grotta di Tiberio, a cave adjacent to the Villa of the emperor Tiberius (1st century AD) located in the archaeological site nearby the National Archaeological Museum of Sperlonga, in the province of Latina. The measures are aimed at verifying whether these structures provide references to particular astronomical events, connected to the apparent motion of the Sun

Self-amplified spontaneous emission for a single pass free-electron laser

SPARC (acronym of "Sorgente Pulsata ed Amplificata di Radiazione Coerente", i.e. Pulsed and Amplified Source of Coherent Radiation) is a single pass free-electron laser designed to obtain high gain amplification at a radiation wavelength of 500 nm. Self-amplified spontaneous emission has been observed driving the amplifier with the high-brightness beam of the SPARC linac. We report measurements of energy, spectra, and exponential gain. Experimental results are compared with simulations from several numerical codes

Impact of Aetiological Treatment on Conventional and Multiplex Serology in Chronic Chagas Disease

The main criterion for treatment effectiveness in Chagas Disease has been the seronegative conversion of previously reactive serology, generally achieved many years post-treatment. The lack of reliable tests to ensure parasite clearance and to examine the effect of treatment is the main difficulty in evaluating treatment for chronic Chagas disease. Decreases of conventional and non-conventional serological titers can be useful tools to monitor the early impact of treatment. We serially measured changes in antibody levels, including seronegative conversion as well as declines in titers in 53 benznidazole-treated and 89 untreated chronically T. cruzi-infected subjects. Seronegative conversion as well as decreases of titers was significantly higher in treated compared with untreated patients. A strong concordance was found between decreases of titers of conventional and non-conventional serologic tests post-treatment, reaffirming the findings. When seronegative conversion plus decreases of titers were considered altogether, the impact of treatment was higher, in a shorter follow-up period than previously considered. New tools for monitoring the effectiveness of treatment of chronic Chagas disease are necessary, and the results showed in this study is a contribution to researchers and physicians who assist patients suffering from this disease

Status of the SPARC-X Project

SPARC-X is a two branch project consisting in the SPARC test facility dedicated to the development and test of critical subsystems such as high brightness photoinjector and a modular expandable undulator for SASE-FEL experiments at 500 nm with seeding, and the SPARX facility aiming at generation of high brilliance coherent radiation in the 1.5-13 nm range, based on the achieved expertise. The projects are supported by MIUR (Research Department of Italian Government) and Regione Lazio. SPARC has completed the commissioning phase of the photoinjector in November 2006. The achieved experimental results are here summarized together with the status of the second phase commissioning plans. The SPARX project is based on the generation of ultra high peak brightness electron beams at the energy of 1 and 2 GeV generating radiation in the 1.5-13 nm range. The construction is at the moment planned in two steps starting with a 1 GeV Linac. The project layout including both RF-compression and magnetic chicane techniques has been studied

Overview of the FTU results

Since the 2018 IAEA FEC Conference, FTU operations have been devoted to several experiments covering a large range of topics, from the investigation of the behaviour of a liquid tin limiter to the runaway electrons mitigation and control and to the stabilization of tearing modes by electron cyclotron heating and by pellet injection. Other experiments have involved the spectroscopy of heavy metal ions, the electron density peaking in helium doped plasmas, the electron cyclotron assisted start-up and the electron temperature measurements in high temperature plasmas. The effectiveness of the laser induced breakdown spectroscopy system has been demonstrated and the new capabilities of the runaway electron imaging spectrometry system for in-flight runaways studies have been explored. Finally, a high resolution saddle coil array for MHD analysis and UV and SXR diamond detectors have been successfully tested on different plasma scenarios