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An overview is presented of the progress since 2021 in the construction and scientific programme preparation of the Divertor Tokamak Test (DTT) facility. Licensing for building construction has been granted at the end of 2021. Licensing for Cat. A radiologic source has been also granted in 2022. The construction of the toroidal field magnet system is progressing. The prototype of the 170 GHz gyrotron has been produced and it is now under test on the FALCON facility. The design of the vacuum vessel, the poloidal field coils and the civil infrastructures has been completed. The shape of the first DTT divertor has been agreed with EUROfusion to test different plasma and exhaust scenarios: single null, double null, X-divertor and negative triangularity plasmas. A detailed research plan is being elaborated with the involvement of the EUROfusion laboratories.

Net erosion of plasma-facing materials was investigated at the low-field-side (outer) strike-point area of the ASDEX Upgrade (AUG) divertor during H-mode discharges with small and frequent ELMs. To this end, Au and Mo marker samples with different surface morphologies and geometries were exposed to plasmas using the DIM-II divertor manipulator. The results were compared to existing erosion and deposition patterns from various L- and H-mode experiments, in the latter case the main difference was the size and frequency of the ELMs.We noticed that increasing surface roughness reduces net erosion but less than what is the case in L-mode. On the other hand, net-erosion rates in H-mode are generally 2–5 times higher than the corresponding L-mode values, in addition to which exposure in H-mode conditions results in strong local variations in the poloidal and toroidal erosion/deposition profiles. The latter observation we associate with the large migration length, on the order of several cm, of the eroded material, resulting in strong competition between erosion and re-deposition processes especially at poloidal distances > 50 mm from the strike point. Considerable net erosion was measured throughout the analysed poloidal region unlike in L-mode where the main erosion peak occurs in the vicinity of the strike point. We attribute this qualitative difference to the slow decay lengths of the plasma flux and electron temperature in the applied H-mode scenario.Both erosion and deposition require detailed analyses at the microscopic scale and the deposition patterns may be drastically different for heavy and light impurities. Generally, the rougher the surface the more material will accumulate on locally shadowed regions behind protruding surface features. However, rough surfaces also exhibit more non-uniformities in the quality or even integrity of marker coatings produced on them, thus complicating the analyses of the experimental data.We conclude that local plasma parameters have a huge impact on the PFC erosion rates and, besides incident plasma flux, surface morphology and its temporal evolution have to be taken into account for quantitative estimates of erosion rates and PFC lifetime under reactor-relevant conditions.

In this work, we discuss the exposures of polycrystalline tungsten (W) and nanostructured W coatings to high energy (~30÷300eV) medium-flux D (~1020m-2s-1) deuterium plasmas of the linear machine GyM at an overall fluence of 1024m-2. The energy and particle flux are tailored to that of charge-exchange neutrals at the vessel main chamber of present-day tokamaks and expected in ITER. Scanning Electron Microscopy measurements show the formation of surface nanostructures that are found to strongly depend on the W morphology and crystallinity, as well as on the energy of the ion species. The obtained nanostructures are few nanometres deep and similar to the one obtained after exposure of bulk W to divertor-like conditions. Dedicated annealing experiments are performed on selected samples, showing that the nanostructures developed on W coatings are thermally stable up to their recrystallisation temperature. The development of micrometric-sized blisters is also observed and found to strongly depend on the features of the W coatings, the substrate and the applied bias voltage.

The influence of surface roughness on the sputter yield was investigated as a function of the angle of incidence. In this work, nm-smooth and rough samples with roughnesses on the µm length scale were produced by depositing thin Fe and W films on smooth and rough Si substrates via magnetron sputtering. The surface morphology of the samples was determined by atomic force microscopy. The samples were exposed to a 6 keV D3+ ion beam (2 keV/D) under various angles of incidence ranging from 0° to 75° with respect to the surface normal to fluences of the order of 1022 D/m2. The layer thickness was measured by Rutherford backscattering spectrometry (RBS) before and after erosion. The resulting sputter yields were compared to simulations performed with SDTrimSP (static and dynamic) and SDTrimSP-3D (static), showing good qualitative agreement in all cases, as well as agreement with literature data at normal incidence. This constitutes the first experimental benchmark of SDTrimSP-3D. A discrepancy in the value of the sputter yield for smooth W at normal incidence was observed between the SDTrimSP simulations and the experimental values obtained in this work and found in literature. Analogous experiments were performed to study the sputter yield at normal incidence of 2 keV/D on smooth Au and 6 keV He on smooth W. These sputter yields were also compared to SDTrimSP simulations and literature, showing good agreement in all cases. Keywords: Sputtering, SDTrimSP, Roughness

The adhesion of tungsten dust is measured on plasma-exposed and non-exposed tungsten substrates with the electrostatic detachment method. Tungsten substrates of comparable surface roughness have been exposed to the deuterium plasmas of the GyM linear device and the argon plasmas of rf glow discharges under conditions which invariably modify the surface composition due to physical sputtering. The adhesion has been systematically characterized for different spherical nearly monodisperse dust populations. Independent of the dust size, an approximate 50% post-exposure reduction of the average and spread of the adhesive force has been consistently observed and attributed to surface chemistry modifications. Keywords: Dust adhesion, Pull-off force, Dust remobilization, Electrostatic detachment, Adsorbates, Sputtering

The use of tin (Sn) as a liquid metal for plasma facing components has been recently proposed as a solution to the high heat load issue on the divertor target plates in nuclear fusion reactors. Due to its low vapor pressure, low reactivity with hydrogen and good resilience to neutron impact, tin is a good candidate as plasma facing component. However its high atomic number poses concerns about plasma contamination.In this paper two fundamental aspects have been investigated: deuterium retention and erosion fluxes from the Sn surface towards the plasma. The samples were exposed to plasma inside the linear machine GyM in magnetic cusp configuration. This setup permits to expose free liquid specimens without the need for the Capillary Porous System. Moreover it permits to lower the magnetic field in order to increase Sn Larmor radius and consequently limit Sn re-deposition in erosion experiments.Ex-situ analyses by ion beam diagnostics on solid samples exposed to deuterium plasma have proved that the amount of retained atomic deuterium is very low, approximately 0.18 at% estimated by Nuclear Reaction Analysis and 0.25 at% estimated by Elastic Recoil Detection Analysis.In the framework of erosion studies, the spectroscopic parameter S/XB was evaluated in Ar plasma for the SnI line at 380.1 nm by Optical Emission Spectroscopy and mass loss measurements in the 5–11 eV Te range, at a density ne ∼ 1.5 × 1011 cm−3. An average value of 150 ± 23 was obtained. Keywords: Liquid metals, Deuterium retention, Erosion, Double-cusp magnetic configuration, Ion beam diagnostics, S/XB spectroscopic parameter

The first experimental determination of the pull-off force for tungsten dust adhered to tungsten surfaces is reported. Dust deposition is conducted with gas dynamics methods in a manner that mimics sticking as it occurs in the tokamak environment. Adhesion measurements are carried out with the electrostatic detachment method. The adhesion strength is systematically characterized for spherical micron dust of different sizes and planar surfaces of varying roughness. The experimental pull-off force is nearly two orders of magnitude smaller than the predictions of contact mechanics models, but in strong agreement with the Van der Waals formula. A theoretical interpretation is provided that invokes the effects of nanometer-scale surface roughness for stiff materials such as tungsten.

Nitrogen used to reduce the power load onto the divertor in tokamak fusion devices (JET, AUG) has the drawback of ammonia formation. Non-negligible quantity of tritiated ammonia could be a serious concern for ITER, since it cannot be reduced through the presently designed fuel cycle loop.In this paper we report a study of the production of ND3 as a function of the electron temperature (Te) and neutral pressure in a N2/D2 plasma mixture in the linear machine GyM. The nitrogenized compounds were monitored by Optical Emission Spectroscopy (OES) and Mass Spectrometry (MS). Measurements were performed at different values of Te ranging from 3eV to 6eV by varying the microwave power (2.45GHz, up to 0.6kW cw) that sustains the plasma, and for different neutral pressure at a constant ratio of nitrogen and deuterium partial pressures. The effect of introduction of He or Ar in the N2/D2 mixtures has been also investigated.The ND3 produced during plasma experiments has been quantified with a dedicated setup based on an in-line LN2 trap and Liquid Ion Chromatography (LIC).Mass-spectrometry results showed that ND3 is formed only during the plasma phase of the experiment while LIC showed that ammonia production increases with Te and with the total neutral pressure. Optical Emission Spectroscopy confirms the presence of ND species in all the cases studied. The addition of He and Ar in the N2/D2 plasma, not modifing Te and ne, causes a reduction of ammonia formation, that is negligible in the case of Ar addition, while in the case of He reaches 80%. This suggests that He modifies the physical chemical process occurring at the wall, where the adsorbed He inhibits the reactions leading to ammonia formation at the metallic surface of the vessel. These results confirm the active role of a metallic surface in ammonia production and indicate He injection as a promising solution to limit the formation of the tritiated ammonia in the N seeded plasma of ITER. Keywords: Nitrogen seeding, Ammonia, Optical spectroscopy, Chromatography, Mass Spectrometer

Iron-tungsten (Fe-W) mixed films were exposed to the low flux deuterium plasma of GyM in order to study the behavior of the sputtering yield with the ion fluence and temperature of the samples. From literature, it is known that an increase of the former lowers the Fe-W layers’ sputtering yield as a consequence of the preferential sputtering of Fe leading to an enrichment in W of the outermost layers. An opposite trend was instead found for the latter probably due to the inter-diffusion of Fe and W (effective from 200 °C) resulting in the suppression of the W enrichment. Moreover, from 500 °C, also W segregation to the surface occurs. What is missing from literature is a systematic investigation of the role of temperature on W enrichment. In this work, dedicated experiments in GyM were carried out to fill this gap. After exposure, W enrichment was evaluated by Rutherford Backscattering Spectrometry (RBS) and inferred from measuring the eroded thickness of the samples using RBS and profilometer. Concerning the Fe-W sputtering yield as a function of fluence, it decreases by a factor of ∼3 between the lowest (3.0×1022D+m−2) and the highest fluence (9.0×1023D+m−2) values considered. The other main result is that, at the lowest fluence, the exposure at room temperature leads to an erosion of the Fe-W samples more pronounced than that associated to the exposure at 500 °C.

Translation articles: G. Savarese, P. Costanzo, J.G.F. Cleland, E. Vassallo, D. Ruggiero, G. Rosano, P. Perrone-Filardi «A Meta-Analysis Reporting Effects of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers in Patients Without Heart Failure» J Am Coll Cardiol 2013;61(2):131-42; http://dx.doi.org/10.1016/j.jacc.2012.10.011

Hearing loss is the most common sensory impairment globally and can affect all ages. It can be classified into two categories, conductive and sensorineural, though both conditions may coexist. Various causes may be responsible for hearing loss including congenital, infectious, inflammatory and neoplastic. Imaging will help detect or exclude such causes and in combination with the medical history and clinical findings, enable the necessary treatment to be initiated. Imaging also provides an accurate pre-operative anatomical road map for the surgeons to ensure the best possible surgical outcomes. The aim of this educational review is to present a range of common and rare diseases causing hearing loss and provide a brief explanation of the best imaging modalities for each. It also discusses briefly some important anatomical variants which the radiologists should highlight in their report to help prevent inadvertent post-operative complications., Competing Interests: Declarations Conflict of interest Ferdinando Caranci serves as an editorial board member for La Radiologia Medica. The other authors have no conflicts of interest to disclose. Ethical standards statement All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards., (© 2024. Italian Society of Medical Radiology.)

Food labeling can influence, sometimes facilitate, changes in consumer diets to support environmental sustainability and in response to climate change. However, a significant impediment to this dietary shift may arise from the consumers' tendency to underestimate the environmental impact of their food choices and from their limited knowledge about sustainable certifications. These aspects are influenced by the characteristics and geographical affiliations of individuals. In such a context, the aim of this research has been to identify the main factors that drive the food purchasing frequency and the changes in food consumption associated with consumers' concerns about climate change and interest in sustainable food certifications by comparing different food products and countries (Italy, France, Germany, Denmark, the USA, and China). A cross-country survey was conducted on 6500 consumers of various food products. The obtained mean scores were then compared, using generalized linear mixed-effect models, to evaluate the associations between the consumers' food purchasing frequency, the importance of sustainable certifications, and changes in food consumption due to climate change concerns. Much of the variation in food consumption, purchasing behaviors, and interest in sustainable certifications was found to depend on such factors as age, gender, and country of origin. Indeed, Chinese consumers exhibited a heightened interest in sustainable food certifications, yet their consumption scores for all food products overall were higher. Conversely, adult and elderly Danish consumers demonstrated a decrease in the consumption of cheeses, meat, fruits, and vegetables, and their interest scores in all sustainable food certifications were lower. Despite the challenges posed by various consumers' interests and minimal changes in food consumption patterns, our findings suggest that sustainable certifications present a promising avenue for straightforward interventions to promote the adoption of sustainable diets and to address climate change., (© 2024. The Author(s).)

Objectives: The aim of this pilot trial is evaluating the preliminary effectiveness of two in-hospital interventions in the maintenance of motor performance in children/adolescents undergoing hematopoietic stem cell transplantation (HSCT). Secondary objectives investigated the interventions' feasibility, impact on fatigue and to what degree the subjects' maintained their ankle dorsiflexion range of movement (ROM), functional mobility, muscle strength and flexibility., Methods: This trial included 5- to 18-year-old participants, affected by oncological and non-oncological diseases during hospitalisation for autologous/allogenic HSCT. The subjects were assigned to an exercise group (EG), or a counselling group based on a cluster model based on inpatient timeframe. The EG subjects performed strengthening, stretching and aerobic exercises for 30 min/5 days a week. Both groups followed rehabilitation counselling indications (RCI), 7 days a week., Results: Forty-nine participants were enrolled (median age = 12.9 years) (EG n = 36). In both groups the participants maintained their baseline motor performance and ankle ROM, and the children/adolescents and parents reduced their levels of fatigue. However, the interventions were not effective in maintaining strength., Conclusion: In maintaining the subjects' motor performance, the RCI results are significant because they pave the way for the application in clinical practice contexts where there are poor rehabilitation resources. Clinical Trials registration NCT03842735., (© 2022 John Wiley & Sons Ltd.)

Background: Catheter-based or surgical procedures in patients with long-standing persistent atrial fibrillation (LSPAF) remain a challenge. As a result, different approaches including hybrid (surgical and endocardial) ablation have been developed. Bachmann's bundle (BB) is a mainly epicardial structure capable of sustaining arrhythmic reentry that could be involved in the development and perpetuation of atrial fibrillation. We investigated the efficacy and safety of an adjunctive BB ablation in LSPAF patients undergoing hybrid ablation., Methods: In a two-arm non-randomized study, consecutive LSPAF patients undergoing epicardial isolation of pulmonary veins with left atrial posterior wall (box lesion) with (n = 30, BB group) and without additional BB ablation (n = 30, CONV group) were enrolled in the study. All patients underwent an endocardial procedure within 6 weeks post-surgery to assess for potential lesion gaps and additional atrial substrate modification. The primary endpoint was freedom from AF through 12 months of follow-up., Results: The two-staged hybrid ablation was successfully completed in all patients. One-year freedom from atrial arrhythmias recurrence rates was 96.6% in the BB group vs 76.6% in the CONV group (p = 0.025). At procedure completion, 30 (100%) and 17 (56%) patients had a spontaneous cardioversion in BB and CONV group, respectively (p < 0.001). No significant differences in quality of life or complication rates were observed., Conclusions: This initial experience shows, for the first time, that adjunctive BB ablation in the setting of hybrid ablation for LSPAF is a feasible and effective approach in increasing maintenance of sinus rhythm without increasing complication rates., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

The process of deep texturization of the crystalline silicon surface is intimately related to its promising diverse applications, such as bactericidal surfaces for integrated lab-on-chip devices and absorptive optical layers (black silicon-BSi). Surface structuring by a maskless texturization appeals as a cost-effective approach, which is up-scalable for large-area production. In the case of silicon, it occurs by means of reactive plasma processes (RIE-reactive-ion etching) using fluorocarbon CF 4 and H 2 as reaction gases, leading to self-assembled cylindrical and pyramidal nanopillars. The mechanism of silicon erosion has been widely studied and described as it is for the masked RIE process. However, the onset of the erosion and the reaction kinetics leading to defined maskless patterning have not been unraveled to date. In this work, we specifically tackle this issue by analyzing the results of three different RIE recipes, specifically designed for the purpose. The mechanism of surface self-nanopatterning is revealed by deeply investigating the physical chemistry of the etching process at the nanoscale and the evolution of surface morphology. We monitored the progress in surface patterning and the composition of the etching plasma at different times during the RIE process. We confirm that nanopattering issues from a net erosion, as contributed by chemical etching, physical sputtering, and by the synergistic plasma effect. We propose a qualitative model to explain the onset, the evolution, and the stopping of the process. As the RIE process is started, a high density of surface defects is initially created at the free silicon surface by energetic ion sputtering. Contextually, a polymeric overlayer is synthesized on the Si surface, as thick as 5 nm on average, and self-aggregates into nanoclusters. The latter phenomenon can be explained by considering that the initial creation of surface defects increases the activation energy for surface diffusion of deposited CF and CF 2 species and prevents them from aggregating into a continuous Volmer-Weber polymeric film. The clusterization of the polymer provides the self-masking effect since the beginning, which eventually triggers surface patterning. Once started, the maskless texturing proceeds in analogy with the masked case, that is, by combined chemical etching and ion sputtering, and ceases because of the loss of ion energy. In the case of CF 4 /H 2 RIE processes at 10% of H 2 and by supplying 200 W of RF power for 20 min, nanopillars of 200 nm in height and 100 nm in width were formed. We therefore propose that a precise assessment of surface defect formation and density in dependence on the initial RIE process parameters can be the key to open a full control of outcomes of maskless patterning., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Background: Multisystem inflammatory syndrome in children (MIS-C) is a rare life-threatening clinical condition that can develop in patients younger than 21 years of age with a history of infection/exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The cardiovascular system is a main target of the inflammatory process that frequently causes myocardial dysfunction, myopericarditis, coronary artery dilation, hypotension, and shock. Multisystem inflammatory syndrome in children-associated myocarditis is usually characterized by fever, tachycardia, non-specific electrocardiogram abnormalities, and left ventricular dysfunction, but serious tachyarrhythmias may also occur. We report two cases of patients with MIS-C-associated myocarditis who developed severe bradycardia., Case Summary: Two female adolescents with recent history of coronavirus disease 2019 (COVID-19) were initially hospitalized for long-lasting high-grade fever and severe gastrointestinal symptoms. Both patients were diagnosed with MIS-C-associated myocarditis for elevation of markers of myocardial injury (mean highly-sensitive cardiac troponin 2663 pg/mL, mean N-terminal-pro-brain natriuretic peptide 5097 pg/mL) and left ventricular dysfunction, which was subsequently confirmed by cardiac magnetic resonance. Both patients developed a severe sinus bradycardia (lowest heart rate 36 and 42, respectively), which appeared refractory to the treatment with intravenous Methylprednisolone and Immunoglobulins, despite a clinical and biochemical improvement. The use of Anakinra (a recombinant interleukin-1 receptor antagonist), was associated with a rapid improvement of cardiac rhythm and excellent clinical outcome at 6 months of follow-up., Discussion: In patients with MIS-C-associated myocarditis, a continuous cardiac monitoring is mandatory to promptly identify potential conduction abnormalities. Adolescents may present bradycardia as a rhythm complication. We experienced a rapid recovery after treatment with Anakinra, to be considered as add-on therapy in cases refractory to standard anti-inflammatory treatment., (© The Author(s) 2021. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Introduction: The transmission rates severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from children to adults are unclear due to a lack of controlled conditions. Materials and Methods: We investigated the occurrence of SARS-CoV-2 transmission among 12 discordant child-parent pairs in our ward. In each hospital isolation room, caregivers and children lived in close contact during the entire hospitalization period. Results: A total of 136 swab-positive children (mean age, 3.6 ± 4.9 median age, 1; IQR 0-6.2, range 0.1-17) attended by their caregivers were hospitalized. Of those, 12/136 (8.8%, mean age, 6.1 ± 5.3 median age, 4.5) were attended by caregivers who were swab and serology negative at admission despite previous close contact with positive children at home. Three children were completely dependent on their mothers, one of whom was being breastfed. The mean duration of overall exposure to the index case was 20.5 ± 8.2 days. Conclusion: None of the infected children transmitted SARS-CoV-2 infection to their caregivers, raising the hypothesis of a cluster of resistant mothers or of limited transmission from children to adults despite prolonged exposure and close contact. These data might provide reassurance regarding school openings and offer the chance of investigating SARS-CoV-2 variants in the future under the same quasi-experimental conditions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Nunziata, Poeta, Vassallo, Continisio, Lo Vecchio, Guarino and Bruzzese.)

Background: Outcomes of catheter ablation (CA) among patients with nonparoxysmal atrial fibrillation (AF) are largely disappointing., Objective: We sought to evaluate the feasibility, effectiveness, and safety of a single-stage stepwise endo-/epicardial approach in patients with persistent/longstanding-persistent AF., Methods: We enrolled 25 consecutive patients with symptomatic persistent (n = 4) or longstanding-persistent (n = 21) AF and at least one prior endocardial procedure, who underwent CA using an endo-/epicardial approach. Our anatomical stepwise protocol included multiple endocardial as well as epicardial (Bachmann's bundle [BB] and ligament of Marshall ablations) components, and entailed ablation of atrial tachycardias emerging during the procedure. The primary outcome was freedom from any AF/atrial tachycardia episode after a 3-month blanking period. The secondary outcome was patients' symptom status during follow-up., Results: The stepwise endo-/epicardial approach allowed sinus rhythm restoration in 72% of patients, either directly (n = 6, 24%) or after AF organization into atrial tachycardia (n = 12, 48%). BB's ablation was commonly implicated in arrhythmia termination. After a median follow-up of 266 days (interquartile range, 96 days), survival free from AF/atrial tachycardia was 88%. Antiarrhythmic drugs could be discontinued in 22 patients (88%). As compared to baseline, more patients were asymptomatic at 9-month follow-up (0% vs. 56%, p = .02). Five patients (20%) developed mild medical complications, whereas one subject (4%) had severe kidney injury requiring dialysis., Conclusion: A single-stage endo-/epicardial CA resulted in favorable rhythm and symptom outcomes in a cohort of patients with symptomatic persistent/longstanding-persistent AF and one or more prior endocardial procedures. Epicardial ablation of BB was commonly implicated in procedural success., (© 2021 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.)

Variation in clinical practice affects veno-occlusive disease management, mainly in patients who undergo allogeneic hematopoietic stem cell transplantation. Disputes about diagnostic criteria, treatment, and prophylaxis, due to the lack of high-quality data, are at the base of this variability. With the aim of limiting inconsistency in clinical care, thus improving both patient outcomes and data collection reliability, the Italian Society of Stem cell transplant (Gruppo Italiano Trapianto Midollo Osseo e Terapia Cellulare) launched a collaborative effort to formulate recommendations based on integration of available evidence and expert's consensus. A systematic method, according to US National Institute of Health guidelines and Italian National System for Guidelines, was used. Twenty-nine recommendations were approved with a strong (20) or weak (9) level of agreement, while 26 were rejected. In particular, the panel pointed out the need to achieve an early diagnosis, encouraging the adoption of European Society for Blood and Marrow Transplantation criteria and the prompt use of ultrasonography. Moreover, our experts strongly recommended in favor of prophylactic use of ursodeoxycholic acid. As soon as a veno-occlusive disease diagnosis is established, treatment with defibrotide should be started for at least 21 days. A number of areas of uncertainty, particularly concerning risk stratification and use of diagnostic tools such as elastography has been identified and discussed., Competing Interests: The authors declare no funding or conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)