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Sheath blight (SB) is one of the most important rice diseases worldwide. It has been difficult to generate SB resistant rice varieties by relying on traditional breeding because resistance to rice SB is a typical quantitative trait. Two QTLs, qSB-7 and qSB-9 on chromosomes 7 and 9, respectively, with SB resistance have been detected in the indica variety Teqing (TQ). Here, we used TQ as the donor to introduce these two resistance QTLs into different commercial japonica varieties through marker-assisted selection and field screening and disease evaluation. Moreover, we have pyramided these two QTLs in the genetic background of japonica variety WLJ1. SB resistance test results showed that the backcrossed lines carrying each of the two QTLs were significantly more resistant to SB than the controls without either of the QTLs, but were significantly less resistant than the lines carrying both QTLs. In the ‘0–9’ disease rating system, qSB-7 TQ and qSB-9 TQ each reduced disease severity by approximately 1.0, while two QTLs pyramided reduced disease severity by 1.7. These results suggest that there is little genetic interaction between the two QTLs. The backcrossed lines carrying either a single QTL or both showed no significant differences in major agronomic and productivity traits as their recurrent parent, demonstrating the suitability of these two QTLs utilized in these japonica varieties. Moreover, we found that these two SB resistance (SBR) QTLs achieved a significant yield loss reduction (14%) from 22.3% to 7.5% in our experimental field conditions. These results constitute an important advancement in SBR research and will facilitate the utilization of qSB-7 TQ and qSB-9 TQ in developing japonica rice varieties with excellent SB resistance.

The helium-cooled ceramic breeder (HCCB) test blanket module (TBM) is the primary option of the Chinese TBM program. Current progress on the design and R&D for Chinese helium-cooled ceramic breeder TBM (CN HCCB TBM) in China is presented. The main updated design and related R&D of CN HCCB TBM are introduced briefly. The mock-up fabrication and component tests for Chinese test blanket module are being carried out. Recent status of the components and fabrication technology development is also reported. The neutron multiplier Be pebbles, tritium breeder Li4SiO4 pebbles, and structure material CFL-1 are being prepared in the laboratory scale. The fabrication of 1/3 sized mock-up and construction of a He test loop are being carried out. The key technology development is proceeding to the large scale mock-up fabrication and demonstration tests toward on ITER testing.

This study aimed to find out whether dietary carotenoid (CD) supplement could influence the resistance of characins (Hyphessobrycon eques Steindachner) to ammonia stress. Two types of CD and its combination [astaxanthin (AX), β-carotene (BC), 1 : 1 combination of AX and BC (MX)] at three concentrations (10, 20 and 40 mg kg−1) were used resulting in nine pigmented diets. No differences in growth and survival of the fish among treatments were found after 8-week rearing. Experimental and control fish were then exposed to 15 mg total ammonia nitrogen L−1 (stress group) and 0.15 mg total ammonia nitrogen L−1 (normal group) for 72 h, and their blood was withdrawn. No mortality resulted under such TAN concentrations. Serum total antioxidant status (TAS), serum antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidases (GPx)] and serum transaminases [alanine aminotransferase (ALT), aspartate aminotransferase (AST)] were chosen as indices of fish antioxidant capacity or stress resistance. SOD, GPx and AST were affected by the interactions of dietary CD and ammonia stress. The activities of TAS, SOD, GPx and AST increased under the stress. Dietary CD reduced serum SOD, GPx, ALT and AST activities. In conclusion, dietary CD increased the resistance of characins to ammonia stress.

Current progress on the design and R&D of Chinese helium-cooled solid breeder test blanket module, CN HCSB TBM is presented. The updated design on structural, neutronics, thermal-hydraulics and safety analysis has been completed. In order to accommodate the HCSB TBM ancillary system, the design and necessary R&Ds corresponding sub-systems have being developed. Current status on the development of function materials, structure material and the helium test loop are also presented. The Chinese low-activation ferritic/martensitic steels CLF-1, which is the structural material for the HCSB TBM is being manufactured by industry. The neutron multiplier Be and tritium breeder Li4SiO4 pebbles are being prepared in laboratory scale.

The basic definition and development strategy of the DEMO plant based on the Chinese fusion power plant (FPP) program are presented briefly. A conceptual design study of fusion HCSB-DEMO reactor with a fusion power of 2550 MW and a neutron wall loading of 2.3 MW/m2 is performed recently. Three sets parameters of core plasma for different DEMO design objectives are proposed. A helium-cooled blanket system with ceramic breeder (Li4SiO4), the structure material of low-activation ferritic steel (LAF/M) and Be neutron multiplier based on Chinese ITER HCSB-TBM design foundation are considered. The design parameters, preliminary analyses and the basic structure as well as development strategy of HCSB-DEMO reactor are introduced.

Testing TBM (Test Blanket Modules) is one of important engineering test objectives in ITER project. China is performing the TBM design and R&D based on Chinese development strategy of fusion DEMO. Helium-cooled test blanket module concept with ceramic breeder for testing on ITER will be one of the basic options in China. The current progress and status on design and R&D of CH HC-SB (Chinese Helium-cooled Solid Breeder) TBM are introduced briefly in this report. The modified designs of HC-SB TBM, related ancillary sub-systems and test strategy on ITER as well as relevant R&D activities are summarized.

The DEMO in China is aimed to demonstrate the safety, reliability and environmental feasibility of the fusion power plants (FPP), meanwhile to demonstrate the feasibility of the prospective economic evaluation of commercial fusion power plants. As known, there is still a long way to go towards an economically competitive commercial power plant, hence DEMO in China is an indispensable step. There are two options of breeding blankets with ceramic and lithium-lead breeders as DEMO blanket concepts under the conditions of meeting the requirement of the neutronics, thermal-hydraulics and mechanics aspects. In this paper, the DEMO blanket development strategy, conceptual design, and related R&D activities, based on China fusion power plants program are presented.

The complexity of the ITER TBM (International Thermonuclear Experimental Reactor Test Blanket Module) and the inventories of radioactive materials involved in its operation require a systematic approach to perform detailed safety analyses during the various stages of the project in order to demonstrate compliance with the safety requirements. A bottom-up methodology based on component level failure mode and effect analysis (FMEA) has been applied to perform the safety analyses for Chinese ITER TBM design with helium-cooled solid breeder (HCSB) concept for testing in ITER device. The main purposes of the work are: to identify important accident initiators, to find out the possible consequences for the TBM deriving from component failures, to identify individual possible causes, to identify mitigating features and systems, to classify accident initiators in postulated initiating events (PIEs), to define the deterministic analyses which allow the possible accident sequences to be quantified, and consequently, to ascertain the fulfillment of ITER safety requirements.

The bulk micro-machining technique is commonly applied to fabricate the silicon micro-cantilever beam. With a micro-probe and special designed fixtures a micro-force testing machine can effectively apply mechanical loading on the beams by bending. This paper is thus aimed at studying the mechanical behavior of single crystal silicon (SCS) micro-cantilever beams by the specific method. The focus is at elucidating failure mechanisms of bent beams since limited studies have been conducted concerning its impact on reliability evaluation. We have fabricated various types of samples that have different lengths and thickness. With various beams in micro-scale, not only the stress–strain relationship can be achieved, but dimension effects on flexural strength, Young’s modulus, and failure strain of MEMS devices can also be precisely evaluated. In addition, locations and failure modes of bent beams are detected by SEM. Based on the microscopic analysis, failure mechanisms are determined for various beams. For reliability analysis purposes it is crucial to determine the location and cause of failure. Data on strength and failure strain as found in the study can be very important for reliability evaluation of SCS such as fatigue life. The testing method can also be easily extended to nano-scale specimens by adding a force magnification lever mechanism.

A novel design of the three-step Langmuir probe (TSLP) array has been developed to investigate the zonal flow (ZF) physics in the HL-2A tokamak. Three TSLP arrays are applied to measure the three-dimensional (3D) features of ZFs. They are separated by 65 mm in the poloidal and 800 mm in the toroidal directions, respectively. The 3D properties of the geodesic acoustic mode (GAM) ZFs are presented. The poloidal and toroidal modes of the radial electric fields of the GAM perturbations are simultaneously determined in the HL-2A tokamak for the first time. The modes have narrow radial wave numbers (kr ρi = 0.03–0.07) and short radial scale lengths (2.4–4.2 cm). High coherence of both the GAM and the ambient turbulence separated by toroidal 22.5 ◦ along a magnetic field line is observed, which contrasts with the high coherence of the GAM and the low coherence of the ambient turbulence apart from the field line. The nonlinear three wave coupling between the turbulent fluctuations and the ZFs is a plausible mechanism for flow generation. The skewness and kurtosis spectra of the probability distribution function of the potential perturbations are contrasted with the corresponding bicoherence for the first time, which support the three wave coupling mechanism.

Recent experiment results from the HL-2A tokamak are presented in this paper. Supersonic molecular beam injection (SMBI) with liquid nitrogen temperature propellant is used. Low temperature SMBI can form hydrogen clusters that penetrate into the plasma more deeply and efficiently. Particle diffusion coefficient and convection velocity (D = 0.5?1.5?m2?s?1 and Vconv < 40?m?s?1, respectively) are obtained at the plasma periphery using modulated SMBI. Multi-probe measurements reveal the m = 0?1, n = 0 symmetries of directly measured low frequency (7?9?kHz) electric potential and field are simultaneously observed for the first time. Impurity transport is determined with the laser blow-off system and transport code. A disruption predictor has been derived based on MHD activity observations and statistical analysis. Sawtooth characteristics during ECRH are investigated and coupling between m = 1 and m/n = 2/1 modes is studied. Detachment features of HL-2A divertor are numerically and experimentally studied using the code SOLPS5.0 and measured data. The long divertor legs and thin divertor throats in HL-2A pose MHD shaping problems resulting in momentum losses even at low densities and strongly enhanced main chamber losses.

Preliminary design and analysis for China helium-cooled solid breeder (CH HC-SB) test blanket module (TBM) for testing in ITER device have been carried out recently. In this paper, the design description, the performance analysis and the related ancillary systems for CH TBM are given. The key features of the design are based upon the breeder-outside-tube (BOT) concept, on the use of solid breeder ceramic material, of helium as coolant and tritium purge gas, of ferrite–martensite steel as structural material and of beryllium as neutron multiplier. Results show that the proposed TBM concept has the advantages of higher tritium breeding ratio (TBR), simple structure design and engineering feasibility.

Two experiment campaigns were conducted on the HL-2A tokamak in 2003 and 2004 after the first plasma was obtained at the end of 2002. Progresses in many aspects have been made, especially in the divertor discharge and feedback control of plasma configuration. Up to now, the following operation parameters have been achieved: Ip = 320 kA, Bt = 2.2 T and discharge duration Td = 1580 ms. With the feedback control of plasma current and horizontal position, an excellent repeatability of the discharge has been achieved. The tokamak has been operated at both limiter configuration and single null (SN) divertor configuration. The HL-2A SN divertor configuration is simulated with the MHD equilibrium code SWEQU. When the divertor configuration is formed, the impurity radiation in the main plasma decreases remarkably.

Recent experimental results from the HL-1M tokamak and progress in the HL-2A project are presented in this paper. In HL-1M, strong fishbone instability was observed during off-axis electron cyclotron resonance heating (ECRH). This is the first observation of fishbone instability purely driven by energetic electrons produced by ECRH. The molecular beam injection (MBI) was first proposed and demonstrated in HL-1M. Recently, new results of the MBI experiment were obtained by increasing the pressure of the gas. A stair-shaped density increment was obtained with high-pressure multi-pulse MBI just like the density evolution behaviour during multi-pellet injection. It is shown that injected particles penetrated into the core region of the plasma. HL-2A is a divertor tokamak constructed at SWIP based on the original ASDEX main components. The mission of the HL-2A project is to explore the physics issues involved in an advanced tokamak. For the first phase, divertor (edge plasma) and confinement research will be emphasized. The major parameters of HL-2A are R = 1.65 m, a = 0.4 m, Bt = 2.8 T, IP = 0.48 MA. The main parameters and characteristics of the subsystems such as power supply, pumping, diagnostics and auxiliary heating are presented in this paper. The first plasma of HL-2A was obtained at the end of 2002.

In the present paper, a new type of DC arc plasma torch is disclosed. The principles of the new magnetic and fluid dynamic controlled large orifice long discharge tunnel plasma torch is discussed. Large area uniformity is achieved through the externally applied magnetic field which stabilizes the arc jet and the proper magnetic and fluid dynamic control which guarantees the dynamic mixing of gases before impinging on to the substrate. The 100 kW high power jet which is newly developed based on the experience of the low power model is equipped with a Φ120 mm orifice torch, and is capable of depositing diamond films over a substrate area of Φ110 mm at a growth rate as high as 40 μm/h, and can be operated in gas recycling mode, which allows 95% of the gases to be recycled. It is demonstrated that the new type DC plasma torch can be easily scaled-up to an even higher power jet. It is estimated that even by the 100 kW Jet, the cost for tool grade diamond films can be as low as less than $4/carat.

The knife edge technique is commonly used to measure tightly focused optical spot profiles with sub-wavelength or nano-meter resolutions. In this paper, we demonstrate a micro scanning knife edge system by using the CMOS-MEMS technology. The scanning actuator, the photodetector, and the signal conditioning circuit, are all integrated and fabricated in the same device by the TSMC 0.35 µm 2P4M technology. The mechanical and electrical properties of various components in the system were characterized. Measurement of focused optical spot profiles at different wavelength and numerical apertures were successfully demonstrated.

Artificial neural networks (ANNs) are increasingly being applied in geophysical data interpretation largely due to the fact that they have been shown to be universal function approximators. However, as ANNs act like "black boxes", there is concern about their reliability. An understanding of the learning of BP neural networks for certain kinds of function approximation can be archived by utilizing the concepts of impulse response from the signal theory. This naturally leads to an algorithm for seismic wavelet extraction constrained by well information. This algorithm is verified with synthetic and real data.

Abstract In this paper we present a data-driven joint inversion of seismic and well data. Rather than using a theoretical operator, we learn the forward operator using a BP neural network trained by the data set with well data as input and seismic recordings near the well as desired output. Then, we start the inversion by inputing the initial model of each trace into the trained BP network and propagating the output errors backward through the network iteratively to modify the input stratum model. The inversion is verified and its robustness analyzed using synthetic data. A field case involving a migrated seismic section and two wells was inverted to obtain the desired pseudo-log sonic and density profiles. The research results show that the technique can perform multiparameter inversion constrained with multiple wells, and deal with complex nonlinear problems. Introduction The strategy of seismic inversion is commonly in looking for an optimal geophysical model which minimizes the residuals between the model responses and observed data. The responses of the model are conventionally calculated by a theoretical forward operator, such as a convolution or wave equation operator1,2. Artificial neural networks(ANN) have recently attracted a great deal of attention for their ability to "learn," or "estimate" the mapping operator from training data which describe the mapping relationship. Among neural networks for function approximation, the feed forward network trained by error back propagation (BP)3 algorithm is one of the most effective and popular neural networks. It has been shown that the BP neural network with one hidden layer is a universal function approximator 4. In the learning of the BP (error back-propagation) neural network, the output error is propagated backward through the network to modify the link weights of the network, and the mapping relationship between the input and desired output vectors is encoded in the weights with a distributed form. Linen and Kinderman5 have shown that the same mechanism of the weight learning can also be applied to update the input of the network to iteratively invert the input parameter model of the network. In their approach, the output errors of the network are ascribed to the input errors of the network, rather than the weight errors. The iterative inversion of a BP network is, thus, to search the input signals in the input space to minimize the output errors, while the learning of it is to find a set of weights in the weight space to minimize the output errors Hoskins and Hwang6 apply the iterative inversion technique to their adaptive controllers. They learn the forward model of the plant, and perform the iterative inversion to generate control commands. They conclude that the proposed control approach allows the controllers to respond on line to changes in plant dynamics. Here, we apply the technique to the joint inversion of well-log and seismic data. We first learn the forward operator using a BP network trained by the data set consisting of well data as input and seismic recordings located at or near the well as desired output. Then upon the trained BP network, we iteratively invert seismic recordings into the stratum parameters trace by trace. As the approximation of the forward operator is adaptively driven by well-log and seismic data and there are no assumptions about the operator and the medium, the inversion can be nonlinear with a high degree of complexity.

The physics experiments on the HL-2A tokamak have been focused on confinement improvement, particle and thermal transport, zonal flow and turbulence, filament characteristics, energetic particle induced modes and plasma fuelling efficiency since 2008. ELMy H-mode discharges are achieved in a lower density regime using a combination of NBI heating with ECRH. The power threshold is found to increase with a decrease in density, almost independent of the launching order of the ECRH and NBI heating power. The pedestal density profiles in the H-mode discharges are measured. The particle outward convection is observed during the pump-out transient phase with ECRH. The negative density perturbation (pump-out) is observed to propagate much faster than the positive one caused by out-gassing. The core electron thermal transport reduction triggered by far off-axis ECRH switch-off is investigated. The coexistence of low frequency zonal flow (LFZF) and geodesic acoustic mode (GAM) is observed. The dependence of the intensities of LFZFs and GAMs on the safety factor and ECRH power is identified. The 3D spatial structures of plasma filaments are measured in the boundary plasma and large-scale structures along a magnetic field line analysed for the first time. The beta-induced Alfvén eigenmodes (BAEs), excited by large magnetic islands (m-BAE) and by energetic electrons (e-BAE), are observed. The results for the study of fuelling efficiency and penetration characteristics of supersonic molecular beam injection (SMBI) are described.

Significant experimental advances have been made on the HL-2A tokamak along with substantial improvement and development of the hardware. A spontaneous particle transport barrier has been observed in Ohmic discharges without any external momentum input. The barrier was evidenced by a density perturbation study using modulated supersonic molecular beam injection (SMBI) and microwave reflectometry. The new features of the non-local transport effect induced with SMBI have been analysed. The three-dimensional spectral structures of the low frequency zonal flow, the geodesic acoustic mode (GAM) and the quasi-mode-like low frequency fluctuations have been observed simultaneously for the first time. In addition, the spectral structure of the density fluctuations of GAM was also identified. The e-fishbone instability excited by energetic electrons deviated from Maxwellian distribution has been investigated via a 10-channel CdTe hard x-ray detector. It was found that the e-fishbone was correlated with the existence of energetic electrons of 30–70 keV. The MHD experiment has indicated that the suppression of m/n = 2/1 tearing modes may be sustained by ECRH modulation at a frequency of about 10 Hz.

International audience; The effects of intraperitoneal injections or pellet implantations of luteinizing hormone-releasing hormone analogues, des-Gly10-[D-ALA6]-LH-RH-ethylamide (LRH-Aa) or des-Gly10-[D-Trp6]-LH-RH-ethylamide (LRH-At), respectively, and the combination of these treatments with pimozide, a dopamine antagonist, on serum gonadotropin (GtH) and ovulation in goldfish held at 18–20°C were investigated. Injections of LRH-Aa (0.1 μg/g body weight) or pellet implants of LRH-At (25 and 125 μg/fish) alone increased serum GtH levels, but were relatively ineffective for inducing ovulation in goldfish (≅ 25% rate of occurrence). Pimozide greatly potentiated the GtH release response to LRH-Aa injections or LRH-At pellet implantations. A high rate of occurrence of ovulation (87%) was observed within 24 h when pimozide was injected prior to or with the first of two injections of LRH-Aa, or following implantations of LRH-At pellets that give continuous release of LRH-At. These results are consistent with the idea that dopamine acts directly at the pituitary level as a GtH release-inhibitory factor in goldfish.