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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]

This research aims to assess the influences of the spatial variability of soil parameters on the ground surface and retaining wall deformation induced by braced excavation. A series of anisotropic random fields are generated and used for the finite difference analysis in this paper. A procedure for automating the Monte Carlo simulation is employed to ascertain the influences of coefficient of variation and scale of fluctuation (SOF) of soil stiffness parameters on the excavation-induced responses. In addition, the effects of horizontal SOF and vertical SOF are distinguished in the anisotropic framework. The stochastic results indicate that the presented computational framework is effective in the investigation of excavation-induced deformations. Further probabilistic analyses are performed to evaluate the failure probabilities of surface settlement (SS) and retaining wall deflection (RWD). This study shows the importance of addressing the spatial variability of stiffness parameters for soil and structure problems. A series of modes for SS and RWD are presented with consideration of the effects of weak stiffness regions. The effects of vertical SOF on excavation-induced deformations are larger than those of horizontal SOF. The concept of vertical SOF correlation is proposed to explain that the most scattered result occurs when the vertical SOF is close to the size of the excavation. The research can provide a beneficial reference for advance warning of failure or hazard when performing probabilistic assessment of excavation-induced deformations. [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]

In this study, the actual drainage condition of in situ soft clay is partially drained and the natural soft soil was subjected to long-term uniform cyclic loading. Cyclic triaxial tests were conducted on remoulded samples to analyse the effect of drainage condition on the dynamic behaviour of Ningbo clay. The results showed that when the cyclic stress ratio (CSR) was small, the accumulated axial strain under undrained conditions was larger than that under partially drained conditions; however, when the CSR was high, the accumulated axial strain in the undrained condition reduced. The resilient strain gradually decreased after a large number of cycles under partially drained conditions, while it increased more significantly with an increase in CSR during the experiments under undrained conditions. With increasing cycle numbers, the pore pressure initially increased and then decreased with a peak value under partially drained conditions, while the pore pressure tended to become stable under undrained conditions. On the basis of the test results, equations for permanent axial strain and pore pressure considering the effect of drainage conditions are proposed, which can predict the dynamic responses of in situ subsoils under long-term uniform cyclic loading. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the long-term effectiveness of first-line antiretroviral therapy in HIV/AIDS patients in Southeast China. A total of 450 eligible patients were selected to initiate first-line antiretroviral therapy from February 2005 through August 2009. During the study period from 2009 through 2013, each subject received clinical and laboratory monitoring for effectiveness, safety and toxicity once every 3 months in the first year, and once every 6 months in the following years. The response to first-line antiretroviral therapy was evaluated through body weight gain and immunological and virological outcomes. During the mean follow-up period of 70.86 ± 28.9 months, the overall mortality was 14.2 %. The mean body weight and CD4 counts increased significantly following antiretroviral therapy as compared to baselines across the follow-up period, and the rate of immunological effectiveness was over 85 % in all subjects at 2 to 5 years of treatment. The rate of inhibition of HIV virus was 87.67 %, 89.32 %, 91.73 %, 92.8 % and 91.63 % across the study period. In addition, significant differences were detected after treatment as compared to baselines, and Pearson correlation analysis revealed a positive correlation between immunological effectiveness and viral inhibition. Forty-eight percent of the subjects changed antiretroviral drugs once, and 16.22 % twice, and 31 patients switched from first-line to second-line antiretroviral therapy. Long-term antiretroviral therapy remains effective for treatment of HIV/AIDS, resulting in higher mean body weight, effective viral inhibition and a higher CD4 count. Immunological effectiveness of antiretroviral therapy positively correlates with HIV viral inhibition. [ABSTRACT FROM AUTHOR]

Qiu, Y.; Chen, J.; Su, W.; Huang, J.; Yi, S., and Wu, J., 2020. An approach to determining lateral pressure considering the decay in permeability coefficient with depth and application to the subsea tunnel of Xiamen Metro Line 2. In: Liu, X. and Zhao, L. (eds.), Today's Modern Coastal Society: Technical and Sociological Aspects of Coastal Research. Journal of Coastal Research, Special Issue No. 111, pp. 145–150. Coconut Creek (Florida), ISSN 0749-0208. The determination of lateral pressure on a tunnel face is a paramount concern during the process of replacing cutting tools for a subsea shield tunnel. In conventional methods for the calculation of lateral pressure, the influence of soil permeability has seldom been considered, and the decay in permeability coefficient with depth has been ignored. In this article, an approach for determining the lateral pressure considering the decay in permeability coefficient with depth is put forward. Based on the previous method considering constant permeability coefficient, two different types of decay mode are considered in the proposed approach. For the linear type, the explicit expressions of the resultant thrust are then derived and set up. For the negative exponential type, a numerical method is needed to calculate the lateral pressure. Then the proposed approach is applied to the Subsea Tunnel of Xiamen Metro Line 2. Based on the results of the application, the linear type is recommended for use in considering the decay in soil permeability coefficient with depth, and the corresponding explicit expressions are recommended for calculation of the lateral pressure in engineering practice. [ABSTRACT FROM AUTHOR]