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For the problem of excessively high divertor heat flux, active impurity seeding is an effective method to radiate the plasma energy reaching the divertor and thus achieve the divertor detachment. Neon is a very effective radiation impurity on many current tokamaks, which is also a candidate species to be applied on ITER. In the EAST 2019 experimental campaign, a series of experiments were performed by seeding a mixture of neon and deuterium (Ne-D2) for detachment and core-edge-divertor integration in H-mode plasmas. The divertor partial detachment with high-confinement core plasma has been achieved by using Ne-D2 seeding in EAST with ITER-like tungsten divertor. Both the plasma stored energy and H 98,y2 > 1.1 are maintained, with the divertor electron temperature, heat flux and the surface temperature near the strike point being all significantly reduced. The differences between Ne-D2 seeding at the scrape-off layer (SOL) upstream and downstream have been experimentally investigated in detail. It is found that impurity seeding at SOL downstream is more beneficial to reducing the divertor electron temperature and peak heat flux. By comparison with experiments using divertor D2 fueling, it is further demonstrated that gas seeding in the SOL downstream will enrich more particles near the strike point, while the seeding in the SOL upstream will influence the entire outer target more evenly. Furthermore, in most of the experiments, gas seeding does not cause obvious toroidal asymmetry in the divertor plasma. However, when D2 is injected in an amount similar to that used to build the plasma, it causes the particle flux near the gas-puff to increase locally, i.e., much more than that at the toroidal location far from the gas-puff location. It is a competition between particle source and transport. When the particle source is stronger, it will naturally increase the local particles. In addition, dedicated experiments with different poloidal distances between impurity seeding and strike point on the radiation ability were carried out. Both experimental results and SOLPS simulation show that the seeding close to the strike point is more conducive to neon ionization and energy radiation.

The compatibility of efficient divertor detachment with high-performance core plasma is vital to the development of magnetically controlled fusion energy. The joint research on the EAST and DIII-D tokamaks demonstrates successful integration of divertor detachment with excellent core plasma confinement quality, a milestone towards solving the critical plasma–wall-interaction (PWI) issue and core-edge integration for ITER and future reactors. In EAST, actively controlled partial detachment with T et,div ∼ 5 eV around the strike point and H 98 > 1 in different H-mode scenarios including the high β P H-mode scenario have been achieved with ITER-like tungsten divertor, by optimizing the detachment access condition and performing detailed experiments for core-edge integration. For active long-pulse detachment feedback control, a 30 s H-mode operation with detachment-control duration being 25 s has been successfully achieved in EAST. DIII-D has achieved actively controlled fully detached divertor with low plasma electron temperature (T et,div ⩽ 5 eV across the entire divertor target) and low particle flux (degree of detachment, DoD > 3), simultaneously with very high core performance (β N ∼3, β P > 2 and H 98 ∼ 1.5) in the high βP scenario being developed for ITER and future reactors. The high-β P high confinement scenario is characterized by an internal transport barrier (ITB) at large radius and a weak edge transport barrier (ETB, or pedestal), which are synergistically self-organized. Both the high-β P scenario and impurity seeding facilitate divertor detachment. The detachment access leads to the reduction of ETB, which facilitates the development of an even stronger ITB at large radius in the high β P scenario. Thus, this strong large radius ITB enables the core confinement improvement during detachment. These significant joint DIII-D and EAST advances on the compatibility of high confinement core and detached divertor show a great potential for achieving a high-performance core plasma suitable for long-pulse operation of fusion reactors with controllable steady-state PWIs.

A new lower tungsten divertor has been developed and installed in the EAST superconducting tokamak to replace the previous graphite divertor with power handling capability increasing from −2 to ∼10 MW m−2, aiming at achieving long-pulse H-mode operations in a full metal wall environment with the steady-state divertor heat flux of ∼10 MW m−2. A new divertor concept, ‘corner slot’ (CS) divertor, has been employed. By using the ‘corner effect’, a strongly dissipative divertor with the local buildup of high neutral pressure near the corner can be achieved, so that stable detachment can be maintained across the entire outer target plate with a relatively lower impurity seeding rate, at a separatrix density compatible with advanced steady-state core scenarios. These are essential for achieving efficient current drive with low-hybrid waves, a low core impurity concentration and thus a low loop voltage for fully non-inductive long-pulse operations. Compared with the highly closed small-angle-slot divertor in DIII-D, the new divertor in EAST exhibits the following merits: (1) a much simpler geometry with integral cassette body structure, combining vertical and horizontal target plates, which are more suitable for actively water-cooled W/Cu plasma facing components, facilitating installation precision control for minimizing surface misalignment, achieving high engineering reliability and lowering the capital cost as well; (2) it has much greater flexibility in magnetic configurations, allowing for the position of the outer strike point on either vertical or horizontal target plates to accommodate a relatively wide triangularity range, δ l = 0.4–0.6, thus enabling to explore various advanced scenarios. A water-cooled copper in-vessel coil has been installed under the dome. Five supersonic molecular beam injection systems have been mounted in the divertor to achieve faster and more precise feedback control of the gas injection rate. Furthermore, this new divertor allows for double null divertor operation and slowly sweeping the outer strike point across the horizontal and vertical target plates to spread the heat flux for long-pulse operations. Preliminary experimental results demonstrate the ‘corner effect’ and are in good agreement with simulations using SOLPS-ITER code including drifts. The EAST new divertor provides a test-bed for the closed divertor concept to achieve steady-state detachment operation at high power. Next step, a more closed divertor, ‘sharp-cornered slot’ divertor, building upon the current CS divertor concept, has been proposed as a candidate for the EAST upper divertor upgrade.

Background Rheumatoid arthritis (RA) is a chronic and progressive autoimmune disease that mainly affects joints. Bone erosion and bone destruction are the characteristic features of RA.1 The mechanism of bone destruction is not fully understood at present. The decrease of apoptosis of human fibroblast-like synoviocytes (FLSs) originating from mesenchymal is involved in the occurrence and development of bone destruction in RA.2 Exosomes are important mediators of biological information and play a part in the occurrence and development of various diseases including RA.3 Objectives The aim of study was to find whether exosomes participate in the pathogenesis of bone destruction in RA. Methods plasma was collected from 10 healthy people and 20 RA patients. According to Sharp-van der Heijde score (SHS), patients were divided into two groups named bone destruction group and non bone destruction group. Exosomes were extracted by Total Exosome Isolation reagent and confirmed by transmission electron microscope and western blot. The internalisation of exosomes was detected by immunofluorescence. Normal FLSs were stimulated with exosomes. Flow cytometry was utilised to detect the alteration of cell cycle and apoptosis rate. The cell proliferation was determined by CCK-8 assay. Apotosis proteins (Bax, BCL-2 and caspase-3) were examined by western blot. The concentrations of TNF-α and IL-1 in the cell supernatants were measured by enzyme-linked immunosorbent assay (ELISA). High-throughput sequencing was used to detect the expression of miRNAs in exosomes. Results There is no difference between exosomes of normal people and RA patients in promoting cell proliferation. However, the exosomes of RA patients can prohibit the cell apoptosis and promote the release of TNF-α and IL-1 from FLSs more effectively. Of these two RA groups, the abilities of bone destruction group exosomes are higher. The expressions of Bcl-2 and caspase-3 in bone destruction group are also significantly higher than that in the non bone destruction group and the normal group. Inversely the expression of Bax in bone destruction group is lower. Additionally, exsomal miR-92a are significantly over expressioned in bone destruction group. Conclusions The study showed that exosomes in the serum of RA patients can prohibit the apoptosis of FLSs and enhance the secretion of inflammatory cytokines to promote bone destruction. Exosomes play an important role in the pathogenesis of RA. Exosomes can be used as a potential predictor for early bone destruction. References [1] Muller-Ladner U, Pap T, Gay RE, Neidhart M, Gay S. Mechanisms of disease: the molecular and cellular basis of joint destruction in rheumatoid arthritis. Nat Clin Pract Rheumatol2005;1(2):102–10. [2] Lee DM, Kiener HP, Agarwal SK, Noss EH, Watts GF, Chisaka O, et al. Cadherin-11 in synovial lining formation and pathology in arthritis. ;Science 2007315 (5814):1006–10. [3] Schorey JS, Bhatnagar S. Exosome function: from tumour immunology to pathogen biology ;Traffic 20089 (6):871–81. Acknowledgements This work was supported by grants from Top Six Types of Talents Financial Assistance of Jiangsu Province Grant (BRA2016527), The Natural Science Foundation of China under Grant (81671616), The Natural Science Foundation of China under Grant (81471603). Disclosure of Interest None declared

We study the light output, light collection efficiency and signal timing of a variety of organic scintillators that are being considered for the upgrade of the hadronic calorimeter of the CMS detector. The experimental data are collected at the H2 test-beam area at CERN, using a 150 GeV muon beam. In particular, we investigate the usage of over-doped and green-emitting plastic scintillators, two solutions that have not been extensively considered. We present a study of the energy distribution in plastic-scintillator tiles, the hit efficiency as a function of the hit position, and a study of the signal timing for blue and green scintillators. We study the light output, light collection efficiency and signal timing of a variety of organic scintillators that are being considered for the upgrade of the hadronic calorimeter of the CMS detector. The experimental data are collected at the H2 test-beam area at CERN, using a 150 GeV muon beam. In particular, we investigate the usage of over-doped and green-emitting plastic scintillator, two solutions that have not been extensively considered. We present a study of the energy distribution in plastic-scintillator tiles, the hit efficiency as a function of the hit position, and a study of the signal timing for blue and green scintillators.

There is hot debate on whether there is a Paleo-Tethyan suture within Qiangtang and on how the suture extends in central Tibet. In situ Hf and U–Pb isotopes, and rare earth element (REE) analyses of zircons, together with bulk chemistry, have helped us identify a significant, and previously unknown stage of subduction-related magmatism along the southern part of the eastern Qiangtang block, north of the Shuanghu suture, central Tibet. SHRIMP and LA-ICP-MS zircon U–Pb data demonstrate that the magmatism started as early as 275 Ma, lasted until 248 Ma, and took place at the same time as blueschist and eclogite were forming in the central Qiangtang high- to ultrahigh-pressure metamorphic belt (QMB). The positive eHf(t) values of the magmatic zircons range from 9.71 to 16.73, and indicate derivation of magma from a relatively uncontaminated, depleted mantle. Variations in eHf(t) values and the REE patterns of magmatic zircons, combined with substantial heterogeneities in the whole-rock chemistry, suggest that the arc-related magmatism occurred in pulses, and was long-lived. The present data can be interpreted in terms of a history of progressive subduction during the Early Permian and Early Triassic, during which time continental fragments of EQ affinity were tectonically eroded and subducted into the mantle, along with the subducted oceanic slab. The temporal and spatial correlations between the arc-like volcanic belt and the high-pressure metamorphic belt suggest a Late Paleozoic ocean (Paleo-Tethys) existed between the western and eastern Qiangtang blocks, and that the ocean was closed by northwards subduction.

An Sn3.5Ag4Ti(Ce, Ga) active solder is used for joining ZnS–SiO 2 ceramic sputtering targets with copper backing plates at 250 °C in air. Direct soldering using the Sn3.5Ag4Ti(Ce, Ga) metal filler has been found to be a reliable and simple technique for ZnS–SiO 2 ceramic bonding with ZnS–SiO 2 and copper. The shear strengths for ZnS–SiO 2 /ZnS–SiO 2 and ZnS–SiO 2 /Cu joints are 6.5 and 5.2 MPa, respectively. The bonding mechanism is described, with emphasis placed on the action of a rare earth element (Ce) and the active metal reaction. The interfacial reaction between Sn3.5Ag4Ti(Ce, Ga) filler metal and copper at temperatures ranging from 120 to 200 °C is conducted and discussed.

Weibull distribution life prediction theory is proposed for analyzing fault diagnosis of scraper conveyor in this paper. The scraper conveyor of coal mining mechanization is one of the important equipments in coal producing process, which may be damaged in the operation of the equipment malfunction or failure and its equipment life is very short. Therefore, the timely working state monitoring system of the scraper conveyor can effectively protect the equipment safe and reliable operation to prevent accidents. Simulation results show the life of scraper conveyor can be analyzed with Weibull distribution life prediction theory to reflect the distribution of the fault, and the fault condition is calculated to prolong the scraper conveyor life. Keywords-life prediction; Weibull distribution; scraper conveyor; failure diagnostic

In coal shearer monitoring system, the early detecting of fault is key technique for preventing the shearer fail. In this paper, the improved support vector machine theory is introduced to detected shearer fault under the mine underground, the improved algorithm based on support vector machine theory is analyzed, the multiple fault classifier is used to judge the fault types of coal shearer. The temperature fault types of coal shearer are reconstructed. Simulation results verify the validity of this method for early detecting fault under strong noise background in the coal shearer monitoring system.

The activation behavior of amorphous Fe90Zr10 and Fe87.8Zr10Co2Al0.2 alloy ribbons and the effect of surface impregnation with KNO3 on the catalytic activity of Fe87.8Zr10Co2Al0.2 have been studied under the condition of ammonia systhesis. The changes of both the bulk structure and the surface state during activation have been investigated by XRD, AES, SAM, XPS and SEM. No activity was detected initially on as-received ribbon surface because the surface was covered by an oxide layer of Zr and Fe. With in situ activation the catalytic activity of the ribbon surface increased gradually, which is closely related to the reduction of Fe oxide, the crystallization of amorphous precursors and the enhancement of the surface area of the ribbons. Impregnation with KNO3 on stream on the ribbon surface could further cause a significant increase of activity, which is expected due to the decomposition of KNO3 into oxide of potassium during in situ activation. The strong surface enrichment of Al was observed on the surface of activated catalyst. The surface structure of active Fe87.8Zr10Co2Al0.2 consists of α-Fe particles and oxides of K, Al and Zr.

Based on the relative relationships between the traffic volumes of intersections, the method of cluster analysis is adopted to classify the intersections in this article. The method is verified through data from the road network of Chang Chun city. This achievement can help us to solve the problem of predicting the traffic volume of the nondetector intersections. It makes it possible to realize the traffic flow guidance in the cites which don't have enough intersections equipped with detectors. Meanwhile it can provide a theory to decide the strategic intersections and to run the strategic intersections with more attention.