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Objective: Wearable ultrasound is emerging as a new paradigm of real-time imaging in freely moving humans and has wide applications from cardiovascular health monitoring to human gesture recognition. However, current wearable ultrasound devices have typically employed pulse-echo imaging which requires high excitation voltages and sampling rates, posing safety risks, and requiring specialized hardware. Our objective was to develop and evaluate a wearable ultrasound system based on time delay spectrometry (TDS) that utilizes low-voltage excitation and significantly simplified instrumentation. Methods: We developed a TDS-based ultrasound system that utilizes continuous, frequency-modulated sweeps at low excitation voltages. By mixing the transmit and receive signals, the system digitizes the ultrasound signal at audio frequency (kHz) sampling rates. Wearable ultrasound transducers were developed, and the system was characterized in terms of imaging performance, acoustic output, thermal characteristics, and applications in musculoskeletal imaging. Results: The prototype TDS system is capable of imaging up to 6 cm of depth with signal-to-noise ratio of up to 42 dB at a spatial resolution of 0.33 mm. Acoustic and thermal radiation measurements were within clinically safe limits for continuous ultrasound imaging. We demonstrated the ability to use a 4-channel wearable system for dynamic imaging of muscle activity. Conclusion: We developed a wearable ultrasound imaging system using TDS to mitigate challenges with pulse echo-based wearable ultrasound imaging systems. Our device is capable of high-resolution, dynamic imaging of deep-seated tissue structures and is safe for long-term use. Significance: This work paves the way for low-voltage wearable ultrasound imaging devices with significantly reduced hardware complexity.

In this article, we report the results from two test campaigns conducted to evaluate the feasibility of implementing a commercially available optical fiber-based distributed sensing technology for Quench Detection (QD) purposes. We successfully characterized the temperature response and sensitivity achievable by this technique when using a bare single mode fiber within a cryogen free cooling system operating in the temperature range from 4 K to 300 K. A fiber was also incorporated into a sample featuring an High-Temperature Superconductor (HTS) stack mounted onto an extruded Aluminum slotted-core cable. Quench-like events were triggered by locally lowering the critical current using the magnetic field produced by a set of permanent magnets placed near the center of the stack. The experiments were carried out at 77 K by cooling the sample through the central channel of the Aluminum core with a forced flow of liquid nitrogen. The test results indicate the viability of this technology as a suitable alternative for QD in long-length HTS cables and motivate further work to develop distributed sensing systems able to work in the conditions foreseen for HTS fusion coils.

Numerous conductor designs for pulsed magnets based on High Temperature Superconductors (HTS), featuring stacks of tapes are currently being proposed. A major contribution to the AC losses is expected to be given by hysteresis losses. Several numerical models have been developed for the computation of hysteresis losses, however the lack of experimental data in conditions relevant for the coil operation did not allow extensive validation of those models. Here, we present the AC loss tests performed on HTS conductor with transport current in conditions of partial or full field penetration. After the validation of a numerical model on those data, we analyze the losses expected during the operation of the EU DEMO CS coil, assessing possible analytical formulations for the calculation of hysteresis losses in DEMO-relevant conditions.

The 1144 Iron-Based Superconductors (IBSC), characterized by the A1AE1Fe4As4 chemical composition (A = Alkaline, AE = Alkaline-Earth), has gained significant interest in the recent years due to their crystalline structure characterized by an intrinsic modulation of the strain along the c-axis and by the proneness in forming crystalline defects with a positive impact on flux pinning. Moreover, it has been proved that the compound is compatible with the cost-effective powder-in-tube (PIT) manufacturing process. In our recent experiments, we have showed that the A1AE1Fe4As4 structure can be tailored to obtain a 1144 compound characterized by different (AxAE1-x)(AEyA1-y)Fe4As4 chemical formulae without any depression in the critical temperature value. On the other hand, it has been recently shown that the doping with selected elements on both A and AE sites has a clear influence on the pinning and the grain boundary properties of poly-crystalline samples. In this work we report the results of the extensive magnetic characterization performed on pristine Ca1K1Fe4As4 and doped (AxCa1-x)(AEyK1-y)Fe4As4 with Ba as dopant on the K site and either La or Na as dopant on the Ca site. In particular, the magnetization hysteresis loops recorded at different temperatures M(H, T) and the critical current density dependences extracted from the M(H) using the Bean model, Jc(B, T), have been analyzed in order to assess the effect of aliovalent doping on the quality of the produced samples in terms of grain boundary properties and pinning efficiency.

Quench caused by electromechanical instabilities is a major concern in high-temperature superconducting (HTS) magnets, and quench detection methods, alternative to common voltage-based systems, are currently under study. In this work, we describe the experimental design and set-up, and we report the results of studies carried out on a cable equipped with bismuth strontium calcium copper oxide (BSCCO) tapes. The sample layout comprises an aluminum slotted core, cooled via a forced flow of liquid nitrogen in the central channel, and liquid nitrogen cooled termination. To trigger a quench in a well-defined position within the stack, a localized small magnetic field is employed to reduce the critical current density in the central zone of the cable. Various configuration of sensors including temperature sensors, voltage taps, and fiber Bragg grating (FBG) are installed, with the final aim of developing a fast and reliable quench detection set-up for the stacked-tapes HTS cable. It is shown that the response for both temperature and FBG signals are comparable for what concerns sensitivity and velocity, and both follow the voltage evolution in time. All in all, the developed setup with the multi-sensor allowed characterizing the electrical and thermal aspects of an HTS slotted-core superconducting cable during a localized magneto-thermal quench.

To protect the Toroidal Field Coils (TFC) of the EU DEMO tokamak, in case it will be realized with low temperature superconducting (LTS) materials, a reliable and fast quench detection system (QDS) is required. Although these TFC coils are operated in static mode, voltages across their winding pack (WP) will be generated during machine operation due to the presence of dynamic magnetic fields. Two sources of magnetic coupling, responsible for noisy signals on the quench detection circuitry in a Fast Plasma Disruption scenario, are here considered and analyzed. Due to the high electromagnetic noise environment, the co-wound (CW) technology must be adopted for the quench sensors and an aligned and twisted layout (CWA&T) is necessary due to the magnetic interaction with the superconductor (SC) strand helicity. The poloidal component of the plasma current is responsible for a noisy signal on the CW and a strategy for signal compensation will be suggested and the contribution evaluated numerically. The signal induced on a SC cable due to the helicity can be compensated adopting a CWA&T configuration. The twist pitch length (TP) of the CWA&T is a critical parameter for a proper noise compensation. Since it is challenging to obtain a reliable TP length from a numerical simulation, we here propose an experimental approach to assess the proper TP length. There is not a constraint on the TP length from the poloidal plasma current induced signal and we can conclude that a single TP, optimized for helicity compensation, will be sufficient.

In many advanced applications, such as Tokamak fusion reactors, the twisted stacked tape cable (TSTC) configuration based on high-temperature-superconducting (HTS) tapes is one of the most promising one. Among the various designs proposed for the European DEMOnstration Fusion Power Plants (DEMO) magnets, several options include conductors based on the HTS-TSTC technology, especially for an Insert of the Central Solenoid (CS). An important main design criterion to be fulfilled by superconducting magnets in operation is related to the temperature margin, which should be lower than a given threshold. For a pulsed magnet as the CS, properly determining its value is only possible with a reliable knowledge of the instantaneous losses entering the superconducting cable. Previous works presented an analytical formulation for the computation of instantaneous magnetisation losses in a HTS-TSTC conductor during a generic cycle of transport current and external magnetic field in phase with each other. Further validation of these formulae is presented by comparison with a 2D numerical model. A complete analysis of a plasma scenario is impossible with this formulation, considering that transport current and external magnetic field are not jointly in phase during the plasma breakdown. This work presents an extension of the previously developed analytical formulae to the more realistic case where the magnetic field and the transport current are not in phase with each other. The new formulae are validated in a case study of technical interest, by comparison with a 1D numerical model suited for the computation of magnetisation losses in these conductors.

Bi-2212 superconducting round wire is one of the candidates for the development of magnets with fields largely above 20 T. One of the most crucial aspects is the possible wire degradation occurring in the cabling process, a mandatory step to achieve a very high current and essential for high field magnets. Here we report a general study on the performance's behaviour of Bi-2212 round wires following a deformation similar to that arising during the cabling assembly. Furthermore, we propose a preliminary 2D Finite Element Model to simulate the mechanical deformation that can be valuable to gain useful information for the development of high-quality cables. In the end, Bi-2212 wires we made and test don't show degradation, consistently with the results of the proposed model which confirms the reliability of the adopted assumptions.

This paper presents a practical parameterization of the critical surface of the 0.82-mm diameter Nb3Sn strands used for the Toroidal Field coils of the Italian Divertor Tokamak Test Facility. The critical current has been measured by means of a Walters Spring device as a function of uniaxial applied strain (±0.5% intrinsic strain) at different field (up to 14 T) and in the temperature range comprised between 4.5 K and 10 K. The experimental results have been analyzed in the framework of the ITER-2008 parameterization and the Extrapolative Scaling Expression, by using a multi-step approach for the data fitting. The accuracy of the scaling laws provides an accurate parameterization of the critical surface in terms of field, temperature and strain, to be used for the characterization and production follow-up of the DTT qualification samples and coils.

Technologies based on High Temperature Superconductors (HTS) are evolving rapidly toward maturity. Within the magnetic confinement fusion environment, several projects are demonstrating the possibility to integrate HTS in the coil systems. With respect to Low Temperature Superconducting (LTS) technologies, HTS could allow extending the operating space of fusion coils, either at higher temperatures, or at higher magnetic field levels, and in any case with larger operating margins. Different perspectives and development strategies are proposed, depending on whether HTS is considered a technology to completely substitute LTS, or to integrate and extend its performance range. A fundamental common requirement is the assessment of the layout, the feasibility, and performance demonstration of high-current conductors. Starting from the results achieved with the Al-slotted core cable-in-conduit conductor, and with a view on existing concepts for standard copper and aluminum cables, we have designed a new HTS sector-cable concept, to allow a flexible conductor design and a robust industrial processing. Several trials have been carried out, to verify the manufacturing approach, using either Al- or Cu-based stabilizers. Prototype sub-cables have been characterized at 77 K and self-field, as a necessary step toward the final target of a CICC operating stably with 60 kA at 4.2 K and 18 T, that is presently of interest for the EU-DEMO Central Solenoid Coil.

The Divertor Tokamak Test facility (DTT) is being constructed in the Research Centre of ENEA Frascati. This nuclear fusion device is devoted to tackle the power exhaust issue in the view of future fusion power plant. The conceptual design and the performances of the DTT superconducting magnet feeders, with NbTi cables, are evaluated based on coupled electromagnetic and structural analyses. We here present a preliminary structural assessment of the feeder clamps. We have considered the self-field condition and the higher force per unit length on feeder paths as evaluated from a 3D EM simulation. The stress state is evaluated by means of a 2D model with plane stress with thickness formulation. Further, the bolt dimension and class, together with the distance between two clamps, is provided in both self-field and maximum force per unit length conditions.

The European post-ITER fusion demonstrator reactor (DEMO) design activities have been ongoing for several years in the framework of the EUROfusion Consortium. The designs proposed for the DEMOnstration Fusion Power Plants (DEMO) magnets include options based on high-temperature superconducting (HTS) technology, namely as an Insert in the Central Solenoid (CS). This work describes the development of tools for the calculation of magnetisation losses in a twisted-stacked HTS cable, which represents one of the most promising configurations of HTS fusion Cable-in-Conduit conductors (CICC). This geometry cannot be tackled with the straightforward application of 1D or 2D models, given their inability to describe the twisting of the tape stacks. However, the methodology proposed in this work allows one to treat the twisting of the conductors by discretizing them in a set of straight pieces. A set of analytical equations is developed to compute the instantaneous power losses in the slab approximation. This fast, easy-to-use, open-access tool, can be employed for the computation of AC losses in the central solenoid modules of a tokamak. In particular, we have applied the model to study the HTS insert of the DEMO central solenoid.

ABSTRACTIntroductionFallopian tube carcinoma (FC) as a single entity is a rare disease. Although its diagnosis is increasing thanks to the widespread use of prophylactic salpingectomy, there are no clinical trials exclusively designed for FC.Areas CoveredThis review aims at identifying the most promising trials and future therapeutic pathways in the setting of FC.Expert OpinionHot topics in FC treatment include the consequences of using PARP inhibitors (PARPi) as first-line therapy, ways to overcome platinum resistance, and the role of immunotherapy. Patient selection is a key point for future development of target therapies. Next-generation sequencing (NGS) is one of the most investigated technologies both for drug discovery and identification of reverse mutations, involved in resistance to PARPi and platinum. New, promising molecular targets are emerging. Notwithstanding the disappointing outcomes when used by itself, immunotherapy in FC treatment could still have a role in combination with other agents, exploiting synergistic effects at the molecular level. The development of cancer vaccines is currently hampered by the high variability of tumor neoantigens in FC. Genomic profiling could be a solution, allowing the synthesis of individualized vaccines.

Advanced ceramics printed with photon-based additive manufacturing deals with anisotropic mechanical properties from the layer-by-layer manufacturing. Motivated by the success in using highly filled transparent slurries containing nanoparticles for powder-based two-photon-polymerization (2PP) for advanced ceramic printing, this works approach is the transfer to Xolography, a volumetric additive manufacturing technology based on linear two-photon excitation and without recoating steps. This paper reports the results of a preliminary investigation optimizing the photocurable slurry to the requirements of Xolography in terms of transparency, over a significantly larger mean free path, compared to 2PP. A feedstock filled with 70 % weight fraction of ceramic particles (∼30 vol%) exhibiting an exceptionally high degree of transparency in the relevant wavelength range of 400–800 nm was prepared from 5 nm zirconia nanoparticles. The high transparency of the photocurable slurry is attributed to the near-monomodal particle size distribution of the zirconia nanoparticles used.