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Superconducting (SC) tokamak JT-60SA plays an essential role in fusion research and development by supporting and complementing the ITER project, providing directions to the DEMO design activity and fostering next generation scientists and engineers. Since the short circuit incident at the terminal joints of equilibrium field coil #1 during the integrated commissioning (IC) in March 2021, both EU and JA implementing agencies (IAs) have examined how to ensure safe operation of JT-60SA by mitigating the risk of possible discharge occurrence inside the cryostat. Based on the experience of the global Paschen tests, the IAs have established a strategy of risk mitigation measures, which is a combination of (i) reinforcement of insulation, (ii) avoiding unnecessary voltage application to the coil systems and (iii) immediate de-energization of the coils when deteriorated vacuum conditions are detected. Thanks to the considerable efforts of the Integrated Project Team members, the IC restarted in May 2023. After confirmation of the SC state of the coil systems (TF, EF and CS), the coil energization test and the plasma operation phase 1 (OP-1) started. The first plasma was successfully achieved on 23 October 2023 with a limited value of voltage and current applied to the coils. The plasma configuration control was also confirmed with low plasma current and low auxiliary heating power conditions. Based on the IO–F4E–QST collaboration, activities of JT-60SA have been shared with the IO and provided an important lesson for ITER assembly and commissioning, and will provide an outstanding contribution to fusion research at large. After OP-1, maintenance & enhancement phase 1 (M/E-1) starts from January 2024, in which in-vessel components are installed, and heating and diagnostic systems are extensively upgraded to allow a high power heating experiment planned in OP-2. In order to make the best use of JT-60SA, a newly organized JT-60SA experiment team will refine the research plan for the future high heating power operation phase.

Recently, experiments on basic plasma physics issues for solving future problems in fusion energy have been performed on a Large Helical Device. There are several problems to be solved in future devices for fusion energy. Emerging issues in burning plasma are: alpha-channeling (ion heating by alpha particles), turbulence and transport in electron dominant heating helium ash exhaust, reduction of the divertor heat load. To solve these problems, understanding the basic plasma physics of (1) wave–particle interaction through (inverse) Landau damping, (2) characteristics of electron-scale (high- k ) turbulence, (3) ion mixing and the isotope effect, and (4) turbulence spreading and detachment, is necessary. This overview discusses the experimental studies on these issues and turbulent transport in multi-ion plasma and other issues in the appendix.

Improvements in electron cyclotron resonance heating (ECRH) and current drive (ECCD) predictions are important issues for the design and control of high-performance fusion plasmas in future devices, where these should play a more important role as actuators than in devices to date. A newly developed EC-prediction package based on the quasioptical ray tracing code PARADE revealed in JT-60SA that (i) the radial profiles of both EC power deposition and driven current are broadened and (ii) the net driven current is increased by a few kA/MW, in comparison with conventional predictions due to dissipative diffractive propagation (DDP). The mechanism of DDP is as follows: EC wave beam obliquely passing through the resonant surface is dissipated non-uniformly on its beam cross section, so that the beam trajectory shifts gradually and thus the resonant position also shifts, resulting in the broadened power deposition profile. This novel ECCD and ECRH prediction package based on PARADE is applicable not only to JT-60SA but other existing devices and even, future devices.

Sharp waves (SPWs) are irregular waves that originate in field CA3 and spread throughout the hippocampus when animals are alert but immobile or as a component of the sleep EEG. The work described here used rat hippocampal slices to investigate the factors that initiate SPWs and govern their frequency. Acute transection of the mossy fibers reduced the amplitude but not the frequency of SPWs, suggesting that activity in the dentate gyrus may enhance, but is not essential for, the CA3 waves. However, selective destruction of the granule cells and mossy fibers by in vivo colchicine injections profoundly depressed SPW frequency. Reducing mossy fiber release with an mGluR2 receptor agonist or enhancing it with forskolin respectively depressed or increased the incidence of SPWs. Collectively, these results indicate that SPWs can be triggered by constitutive release from the mossy fibers. The waves were not followed by large after-hyperpolarizing potentials and their frequency was not strongly affected by blockers of various slow potassium channels. Antagonists of GABA-B mediated IPSCs also had little effect on incidence. It appears from these results that the spacing of SPWs is not dictated by slow potentials. However, modeling work suggests that the frequency and variance of large mEPSCs from the mossy boutons can account for the temporal distribution of the waves. Together, these results indicate that constitutive release from the mossy fiber terminal boutons regulates the incidence of SPWs and their contribution to information processing in hippocampus.

Abstract Background Para-aortic lymph node (PALN) metastases from primary pelvic malignancies are often treated with resection, but recurrence is common. We report toxicity and oncologic outcomes for patients with PALN metastases from gastrointestinal and gynecologic malignancies treated with resection and intraoperative electron radiotherapy (IORT). Methods We retrospectively identified patients with recurrent PALN metastases who underwent resection with IORT. All patients were included in the local recurrence (LR) and toxicity analyses. Only patients with primary colorectal tumors were included in the survival analysis. Results There were 26 patients with a median follow up of 10.4 months. The rate of para-aortic local control (LC) was 77% (20/26 patients) and the rate of any cancer recurrence was 58% (15/26 patients). Median time from surgery and IORT to any recurrence was 7 months. The LR rate for those with positive/close margins was 58% (7/12 patients) versus 7% (1/14 patients) for those with negative margins (p = 0.009). 15% (4/26 patients) developed surgical wound and/or infectious complications, 8% (2/26 patients) developed lower extremity edema, 8% (2/26 patients) experienced diarrhea, and 19% (5/26 patients) developed an acute kidney injury. There were no reported nerve injuries, bowel perforations, or bowel obstructions. For patients with primary colorectal tumors (n = 19), the median survival (OS) was 23 months. Conclusions We report favorable LC and acceptable toxicity for patients receiving surgical resection and IORT for a population that has historically poor outcomes. Our data show disease control rates similar to literature comparisons for patients with strong risk factors for LR, such as positive/close margins.

Abstract Alternating electric fields have been successfully applied to cancer cells in-vitro to disrupt malignant progression and this antimitotic therapy has now been proven to be efficacious in Phase II and Phase III randomized clinical trials of patients with glioblastoma. With additional clinical trials ongoing in a number of other malignancies, there is a crucial need for a better understanding of the radiographic predictors of response and standardization of surveillance imaging interpretation. However, many radiologists have yet to become familiarized with this emerging cancer therapy and there is little active investigation to develop prognostic or predictive imaging biomarkers. This article provides an overview of the pre-clinical data that elucidate the biologic mechanisms of alternating electric fields as a cancer therapy. Results from clinical trials in patients with glioblastoma are then reviewed while elaborating on the several limitations to adoption of this promising line of treatment. Finally, a proposal for the development of imaging markers as a means of overcoming some of these limitations is made, which may improve treatment utilization by augmenting patient selection not only in glioblastoma, but also other malignant conditions for which this therapy is currently being evaluated.