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The Water-Cooled Lithium–Lead blanket concept is a candidate breeding blanket concept for the EU DEMO reactor and it is going to be tested as one of the Test Blanket Modules (TBM) inside the ITER reactor. A major safety issue for its design is the interaction between PbLi and water caused by a tube rupture in the breeding zone, the so-called in-box LOCA (Loss of Coolant Accident) scenario. This issue has been investigated in the framework of FP8 EUROfusion Project Horizon 2020 and is currently ongoing in FP9 EUROfusion Horizon Europe, defining a strategy for addressing and solving WCLL in-box LOCA. This paper discusses the efforts pursued in recent years to deal with this key safety issue, providing a general view of the approach, a timeline, research and development, and experimental activities. These are conducted to master dominant phenomena and processes relevant to safety aspects during the postulated accident, to enhance the predictive capability and reliability of selected numerical tools, and to validate and qualify models and codes and the procedures for their applications, including coupling and chains of codes.

The WCLL Breeding Blanket of DEMO and the Test Blanket Module (TBM) of ITER require accurate R&D activities, i.e., concept validation at a relevant scale and safety demonstrations. In view of this, the strategic objective of the Water Loop (WL) facility, belonging to the W-HYDRA experimental platform planned at C.R. Brasimone of ENEA, is twofold: to conduct R&D activities for the WCLL BB to validate design performances and to increase the technical maturity level for selection and validation phases, as well as to support the ITER WCLL Test Blanket System program. Basically, the Water Loop facility will have the capability to investigate the design features and performances of scaled-down or portions of breeding blanket components, as well as full-scale TBM mock-ups. It is a large-/medium-scale water coolant plant that will provide water coolant at high pressure and temperature. It is composed by single-phase primary (designed at 18.5 MPa and 350 °C) and secondary (designed at 2.5 MPa and 220 °C) systems thermally connected with a two-phase tertiary loop acting as an ultimate heat sink (designed at 6 bar and 80 °C). The primary loop has two main sources of power: an electrical heater up to about 1 MWe, installed in the cold side, downstream of the pump and upstream of the test section, and an electron beam gun acting as a heat flux generator. The WL has unique features and is designed as a multi-purpose facility capable of being coupled with the LIFUS5/Mod4 facility to study PbLi/water reaction at a large scale. This paper presents the status of the Water Loop facility, highlighting objectives, design features, and the analyses performed.

Within the EUROfusion roadmap for the technological development of the European-DEMOnstration (EU-DEMO) reactor, a key point has been identified in the discontinuous operation (pulse-dwell-pulse) of the machine. Water Cooled Lithium Lead (WCLL) Breeding Blanket (BB) Primary Heat Transfer Systems (PHTSs) adopt technology and components commonly used in nuclear fission power plants, whose performances could be negatively affected by the above mentioned pulsation, as well as by low-load operation in the dwell phase. This makes mandatory a full assessment of the functional feasibility of such components through accurate design and validation. For this purpose, ENEA Experimental Engineering Division at Brasimone R.C. aims at realizing STEAM, a water operated facility forming part of the multipurpose experimental infrastructure Water cooled lithium lead -thermal-HYDRAulic (W-HYDRA), conceived to investigate the water technologies applied to the DEMO BB and Balance of Plant systems and components. The experimental validation has the two main objectives of reproducing the DEMO operational phases by means of steady-state and transient tests, as well as performing dedicated tests on the steam generator aiming at demonstrating its ability to perform as intended during the power phases of the machine. STEAM is mainly composed of primary and secondary water systems reproducing the thermodynamic conditions of the DEMO WCLL BB PHTS and power conversion system, respectively. The significance of the STEAM facility resides in its capacity to amass experimental data relevant for the advancement of fusion-related technologies. This capability is attributable to the comprehensive array of instruments with which the facility will be equipped and whose strategic location is described in this work. The operational phases of the STEAM facility at different power levels are presented, according to the requirements of the experiments. Furthermore, a preliminary analysis for the definition of the control strategy for the OTSG mock-up was performed. In particular, two different control strategies were identified and tested, both keeping the primary mass flow constant and regulating the feedwater mass flow to follow a temperature set-point in the primary loop. The obtained numerical results yielded preliminary feedback on the regulation capability of the DEMO steam generator mock-up during pulsed operation, showing that no relevant overtemperature jeopardized the facility integrity, thanks to the high system responsivity to rapid load variations.

Abstract Objective First-line therapy for metastatic squamous cell carcinoma of the head and neck (R/M HNSCC) has been revolutionized by the introduction of anti-checkpoint monoclonal antibodies, which have shown a significant improvement in overall survival (OS) gaining approval in a first line setting. Efficacy and safety of first-line weekly chemotherapy, compared to 3-weeks treatment, was retrospectively evaluated in a frail patient population with R/M HNSCC with the aim to evaluate its role as part of a personalized first-line approach. Methods A total of 124 patients with locally incurable R/M HNSCC receiving weekly (21) or three-weekly (103) chemotherapy plus cetuximab in a first line setting from December 2010 to September 2020 were retrospectively reviewed. Treatment outcomes in terms of objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and toxicities were analysed. Results Patients in the three-week subgroup were ECOG PS 0 (39) and 1 (64) while patients in weekly group (21) were all PS 2. No significant differences were reported in terms of age, sex, smoking and previous alcohol abuse considering the two distinct subgroups. Moreover, no statistically significant difference was found in PFS and OS between the two treatment subgroups. The response rate was 35% (36 patients) and 34% (7 patients) in three-week and weekly treatment group, respectively. Seventy patients (68%) in the three-week group experienced chemotherapy-related toxicities, predominantly G3. In the weekly group a predominantly low-grade toxicity was found in a lower number of patients (52%). Conclusion The weekly schedule appears to be an active and safe strategy in frail patients with R/M HNSCC. Based on these data, a weekly schedule could be considered as a first line treatment in all frail patients excluded from pembrolizumab treatment and a study on the combination of weekly chemotherapy and immunotherapy should be performed.

Recent R&D activities in nuclear fusion have identified the DEMO reactor as the ITER successor, aiming at demonstrating the technical feasibility of fusion plants, along with their commercial exploitation. However, the pulsed operation of the machine causes an “unconventional” operation of the system, posing unique challenges to the functional feasibility of the steam generator, for which it is necessary to define and qualify a reference configuration for DEMO. In order to facilitate the transitions between different operational regimes, the Once Through Steam Generator (OTSG) is considered to be a suitable choice for the DEMO primary heat transfer systems, being characterized by lower thermal inertia with respect to the most common U-tube steam generators. In this framework, the ENEA has undertaken construction of the STEAM facility at Brasimone R.C., aiming at characterizing the behavior of the DEMO OTSG and related water coolant systems in steady-state and transient conditions. A dedicated OTSG mock-up has been conceived and designed, adopting a scaling procedure, keeping the height 1:1 of the DEMO OTSGs. The conceptual design has been supported by RELAP5/Mod3.3 thermal-hydraulic calculations. CFD and FEM codes have been used for fluid-dynamic analyses and mechanical stress analyses, respectively, in specific parts of the component.

In the framework of the EUROfusion Horizon Europe Programme, ENEA and its linked third parties are in charge of the conceptual design of the steam generators belonging to EU DEMO WCLL Breeding Blanket Primary Heat Transfer Systems (BB PHTSs). In particular, in 2021, design activities and supporting numerical simulations were carried out in order to achieve a feasible and robust preliminary concept design of the Once Through Steam Generators (OTSGs), selected as reference technology for the DEMO Balance of Plant at the end of the Horizon 2020 Programme. The design of these components is very challenging. In fact, the steam generators have to deliver the thermal power removed from the two principal blanket subsystems, i.e., the First Wall (FW) and the Breeding Zone (BZ), to the Power Conversion System (PCS) for its conversion into electricity, operating under plasma pulsed regime and staying in dwell period at a very low power level (decay power). Consequently, the OTSG stability and control represent a key point for these systems’ operability and the success of a DEMO BoP configuration with direct coupling between the BB PHTS and the PCS. In this paper, the authors reported and critically discussed the FW and BZ steam generators’ thermal-hydraulic and mechanical design, the developed 3D CAD models, as well as the main results of the stability analyses and the control strategy to be adopted.

The water-cooled lead lithium breeding blanket (WCLL BB) is one of two BB candidate concepts to be chosen as the driver blanket of the EU-DEMO fusion reactor. Research activities carried out in the past decade, under the umbrella of the EUROfusion consortium, have allowed a quite advanced reactor architecture to be achieved. Moreover, significant efforts have been made in order to develop the WCLL BB pre-conceptual design following a holistic approach, identifying interfaces between components and systems while respecting a system engineering approach. This paper reports a description of the current WCLL BB architecture, focusing on the latest modifications in the BB reference layout aimed at evolving the design from its pre-conceptual version into a robust conceptual layout. In particular, the main rationale behind design choices and the BB’s overall performances are highlighted. The present paper also gives an overview of the integration between the BB and the different in-vessel systems interacting with it. In particular, interfaces with the tritium extraction and removal (TER) system and the primary heat transfer system (PHTS) are described. Attention is also paid to auxiliary systems devoted to heat the plasma, such as electron cyclotron heating (ECH). Indeed, the integration of this system in the BB will strongly impact the segment design since it envisages the introduction of significant cut-outs in the BB layout. A preliminary CAD model of the central outboard blanket (COB) segment housing the ECH cut-out has been set up and is reported in this paper. The chosen modeling strategy, adopted loads and boundary conditions, as well as obtained results, are reported in the paper and critically discussed.

A computational campaign was carried out at the Department of Astronautical, Electrical and Energy Engineering of Sapienza University of Rome aiming at the assessment of RELAP5-3D© capabilities for subchannel analysis. More specifically, the investigation involved a lead-bismuth-eutectic–cooled wire-spaced fuel pin bundle and compared simulation outcomes with experimental data coming from the NAtural CIrculation Experiment-Upgraded (NACIE-UP) facility, hosted at ENEA Brasimone Research Center. Thermal-hydraulic nodalization of the facility was developed with detailed subchannel modeling of the fuel pin simulator (FPS). Three different methodologies for the subchannel simulation were investigated, increasing step by step the complexity of the thermal-hydraulic model. In the simplest approach, the subchannels were modeled one by one. In addition, mass transfer between them was considered thanks to multiple cross junction components, realizing the hydraulic connection between adjacent subchannels. In this case, mass transfer depends on the pressure gradient and hydraulic resistance only, ignoring the turbulent mixing promoted by the wire-wrapped subassembly. Simulation results were not satisfactory, and an improvement was introduced in the second approach. In this case, several control variables calculate at each time step the energy transfer between adjacent control volumes associated with the turbulent mixing induced by the wires. This energy is transferred using ad hoc heat structures (HSs), where the boundary conditions are calculated by the control variables. The present model highlighted good capabilities in the prediction of the radial temperature distribution within the FPS, considerably reducing disagreement with experimental data. Finally, the influence of radial conduction within the fluid domain was assessed, introducing further HSs. Although this most complex model provided the best estimation of the experimental acquisition, the improvements given by radial conduction were not so relevant to justify the correspondent increase of the computational cost. [ABSTRACT FROM AUTHOR]

The Breeding Blanket (BB) is one of the key components of the European Demonstration (EU-DEMO) fusion reactor. Its main subsystems, the Breeder Zone (BZ) and the First Wall (FW), are cooled by two independent cooling circuits, called Primary Heat Transfer Systems (PHTS). Evaluating the BB PHTS performances in anticipated transient and accident conditions is a relevant issue for the design of these cooling systems. Within the framework of the EUROfusion Work Package Breeding Blanket, it was performed a thermal-hydraulic analysis of the PHTS during transient conditions belonging to the category of “Decrease in Coolant System Flow Rate”, by using Reactor Excursion Leak Analysis Program (RELAP5) Mod3.3. The BB, the PHTS circuits, the BZ Once Through Steam Generators and the FW Heat Exchangers were included in the study. Selected transients consist in partial and complete Loss of Flow Accident (LOFA) involving either the BZ or the FW PHTS Main Coolant Pumps (MCPs). The influence of the loss of off-site power, combined with the accident occurrence, was also investigated. The transient analysis was performed with the aim of design improvement. The current practice of a standard Pressurized Water Reactor (PWR) was adopted to propose and study actuation logics related to each accidental scenario. The appropriateness of the current PHTS design was demonstrated by simulation outcomes.

Objective: The aim of this study was to investigate the association between cancer patients' ability to share information about their illness with their social network and attachment style dimensions, alexithymia, and quality of life. We hypothesised that ability to share information about one's cancer with family, friends, and medical teams would be positively associated with quality of life and secure attachment and negatively associated with alexithymia., Methods: Forty-five cancer patients were recruited from the Psycho-oncology Unit of the San Camillo-Forlanini Hospital in Rome. We collected anamnestic data and self-report data on social sharing ability, quality of life, alexithymia, and attachment., Results: Sharing with family (B = 4.66; SE = 1.82; β = .52; SE = 0.20; t(41) = 2.6; P = .0143) was the only predictor of global health status, and attachment security was the only predictor of mean social sharing (B = 0.25; SE = 0.06; β = .63; SE = 0.14; t(41) = 4.4; P < .0001)., Conclusions: Encouraging patients to share information about their experience of cancer may help to improve their quality of life. Attachment security seems to promote social sharing. Psychological assessments of cancer patients should cover both ability to share information about one's cancer with family and attachment security., (Copyright © 2016 John Wiley & Sons, Ltd.)

Background: Aim of the study was to prospectively assess the relation between atrial fibrillation, cognitive impairment, frailty and disability in older patients with chronic heart failure ., Methods: Three hundred thirty-one ambulatory community-living patients aged 70 years and older (mean 78 ± 6; range 70-93; 43% women) in stable conditions and optimized therapy were enrolled in seven heart failure cardiology clinics. Cognitive impairment was defined by a corrected Mini Mental State Examination score less than 24. Gait speed was used as marker of frailty and measured on a 4 m distance at usual pace., Results: Ninety-eight patients (30%) were on atrial fibrillation at enrolment and 20 (6%) had a history of paroxysmal/persistent atrial fibrillation. Patients with atrial fibrillation were more frequently women with severe valvular disease, preserved left ventricular ejection fraction and less frequently on beta-blockers. At multivariable analyses, atrial fibrillation emerged as independently related to cognitive impairment [odds ratio (OR) 1.909 (1.072-3.397); P = 0.028], as well as to reduced gait speed [OR 4.366 (2.104-9.060); P < 0.001]. Furthermore, atrial fibrillation was significantly associated with disability in either basic or instrumental activities of daily living. No differences were found in mortality and morbidity., Conclusion: Among patients with chronic heart failure, those with atrial fibrillation present a high prevalence of frailty, cognitive impairment and disability. The hypothetical mechanisms by which atrial fibrillation and heart failure may affect these conditions are multiple and further studies are warranted. However, screening for these variables in clinical practice is simple and inexpensive and may allow better strategies for intervention in this high-risk population.