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An alternative local electrostatic gyrokinetic eigenvalue code is developed for the ion-temperature-gradient-driven mode, the trapped-electron mode (TEM), and the electron-temperature-gradient (ETG)-driven mode. It numerically solves the linear eigenvalue problem for the electrostatic drift waves in the Fourier transformed space and benchmarks well with the HD-7 code and FULL code. The linear ETG and TEM instabilities in the electron thermal internal transport barrier (eITB) with dominant electron heating in experimental advanced superconducting tokamak are analyzed by using this code. The linear analysis results are consistent with that from the critical electron-temperature-gradient threshold analysis. Moreover, the sensitivity of ETG and TEM instabilities to parameters during the eITB formation has been investigated. For the typical eITB discharge, it is found that the instability of ETG mode is more sensitive to the stabilizing effect of the electron–ion temperature ratio (τe), while the instability of TEM is more sensitive to the destabilizing effect of η e . In addition, mixing length estimation of the turbulent transport in the eITB is also discussed, which suggests that the TEM may be saturated by other nonlinear effects than the resonance broadening. [ABSTRACT FROM AUTHOR]

The investigation of the two-dimensional (2D) linear ion-temperature-gradient (ITG) mode in toroidal plasma is carried out in ballooning mode representation. A novel approach to solve the radial envelope structure is proposed by constructing radial differential eigenequation. The important lemma (∂ ω / ∂ θ k) | θ k = 0 = 0 is proved and employed to construct a numerically solvable eigenequation. We have developed a numerical solver which gives the 2D solution consistent with the results obtained by the gyrokinetic global simulation code. Our newly proposed method presents an alternative solution to the 2D ITG eigenvalue problem. [ABSTRACT FROM AUTHOR]

In the IFMIF-DONES facility of the future, the back-plate behind the Li target will receive strong irradiation from high-energy neutrons. The potential use of the back-plate for material specimens is attractive with respect to providing complementary irradiation data for Eurofer. In this work, DPA (displacement per atom) and gas production rates as well as DPA gradients and temperature distributions have been studied for the center segment of the back-plate, using both a nominal beam and a reduced beam footprint. It is shown that specimens can be produced with high DPA in similar conditions to the DEMO first-wall. Based on the size of the SSTT (small specimen test technology) specimens, the limited number of samples obtainable from the adopted arrangement scheme is driven by a major constraint: the thickness of the back-plate. A parametric study of the back-plate's thickness provides an alternative arrangement scheme; thus, the DPA and gradient of the specimens are remarkably improved. [ABSTRACT FROM AUTHOR]

Integration of safety aspects in IFMIF-DONES design is a main objective of EUROfusion and European Commission projects. IFMIF-DONES will be a radioactive facility of the first category, and stringent safety objectives must be achieved and demonstrated. A very low acceptable risk for the worker, the public and the environment is the main principle in the design phase. The progress of safety activities is performed iteratively as detailed engineering develops, taking into account the uniqueness of the facility: a high-power deuterons accelerator (125 mA, 40 MeV), a target of flowing liquid lithium, traps for activation products, a dedicated-design module for irradiated samples, a massive shielding cooled room with confinement function, and a number of conventional systems with safety functions. Several phases are developed: (i) identification of sources and materials at risk, radioactive and nonradioactive, subject to potential mobilization, (ii) failure mode analysis and effects of systems, starting at the functional level, and support with probabilistic analysis, (iii) identification of scenarios leading to unacceptable risk if unmitigated, (iv) proposal of layers of defense by means of safety-credited components and design features, (v) deterministic analysis of scenarios in support of requirements, and (vi) definition and demonstration of safety requirements charged to components. [ABSTRACT FROM AUTHOR]

Mounting evidence demonstrates a close relationship between sleep disturbance and mood disorders, including major depression disorder (MDD) and bipolar disorder (BD). According to the classical two-process model of sleep regulation, circadian rhythms driven by the light–dark cycle, and sleep homeostasis modulated by the sleep–wake cycle are disrupted in mood disorders. However, the exact mechanism of interaction between sleep and mood disorders remains unclear. Recent discovery of the glymphatic system and its dynamic fluctuation with sleep provide a plausible explanation. The diurnal variation of the glymphatic circulation is dependent on the astrocytic activity and polarization of water channel protein aquaporin-4 (AQP4). Both animal and human studies have reported suppressed glymphatic transport, abnormal astrocytes, and depolarized AQP4 in mood disorders. In this study, the "glymphatic dysfunction" hypothesis which suggests that the dysfunctional glymphatic pathway serves as a bridge between sleep disturbance and mood disorders is proposed. [ABSTRACT FROM AUTHOR]

Cu+ -modified SBA-15 (Cu+/SBA-15 , SBA-15 refers well-ordered hexagonal mesoporous silica) was prepared for adsorption of tetracycline (TC) by the pH adjusting reduction method. Some Cu+ species (Cu2O) are aggregated on the outside surface of SBA-15, and the other Cu+ species are highly dispersed in SBA-15 via ≡Si-O-Cu. Its adsorption mechanism was firstly studied via comparison with CuO/SBA-15. The TC adsorption kinetic of Cu+/SBA-15 fitted the pseudo-second-order model well. The adsorption isotherms at 293, 303, and 313 K were determined and modeled with Langmuir and Freundlich equations, and the Qmax of Cu+/SBA-15 for TC calculated from Langmuir model could reach 961.54 mg/g at 313 K. Its good adsorption performance for TC is associated with the high surface area of SBA-15, highly dispersed Cu+ species, and mesoporous structure. The adsorption of Cu+/SBA-15 for TC is an endothermic process, and adsorption heat is 66.88 kJ·mol−1 , which implies that the adsorption process of Cu+/SBA-15 for TC is weak chemisorption. The adsorption mechanism of Cu+/SBA-15 was mainly explored via comparing with CuO/SBA-15 by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) spectroscopy analysis. Besides the coordination complexation of Cu+ with NH2 radical of TC, the π -complexation between Cu+ , and the benzene ring of TC improved the adsorption capacity of Cu+/SBA-15 for TC comparing with CuO/SBA-15 and showed a dominant role for TC adsorption. [ABSTRACT FROM AUTHOR]