The EAST research program aims to demonstrate steady-state long-pulse advanced high-performance H-mode operations with ITER-like poloidal configuration and RF-dominated heating schemes. Since last IAEA FEC, EAST has been upgraded with all ITER-relevant auxiliary heating and current drive systems, enabling the investigation of plasma profile control by coupling/integration of various combinations. By means of the 4.6 GHz and 2.45 GHz LHCD systems, H-mode can be obtained and maintained at relatively high density, even up to n e ~ 4.5 × 10 19 m-3 , where a current drive effect is still observed. Significant progress has been achieved on EAST, including: i). Demonstration of a steady-state scenario (fully non-inductive with V loop ~ 0.0V at high β P ~ 1.8 and high performance (H 98,y2 > 1.0) in upper single-null (ε ~ 1.6) configuration with the tungsten divertor; ii) Discovery of a stationary ELM-stable H-mode regime with 4.6 GHz LHCD; iii) achievement of ELM suppression in slowly-rotating H-mode plasma with the application of n = 1 and 2 RMPs.

To exploit a new collagen resource from the body wall of tropical sea cucumber, pepsin-solubilized collagen of Stichopus monotuberculatus (PSC-Sm) was isolated and characterized with UV-vis spectra, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), amino acid composition, enzyme-digested peptide maps, Fourier transform infrared spectroscopy (FTIR), maximum transition temperature (Tm ), and solubilities. The maximum absorbance of PSC-Sm was exhibited at 218 nm in UV-vis spectra. The triple helical structure and activity of PSC-Sm could be indicated by FTIR. SDS-PAGE showed that the triple helix of PSC-Sm was formed as (α1 )3 by 3 α1 chain homologous with molecular weight of 137 kDa. The Tm of PSC-Sm and calf skin collagen (CSC) were 30.2 and 35.0 ºC, respectively, which consistent with the result of FTIR that CSC contained more stable triple-helix than PSC-Sm. Peptide maps were different between PSC-Sm and CSC, indicating the differences in their amino acid compositions and sequences. The maximum and minimum solubilities of PSC-Sm were observed at pH 2.0 and 4.0, respectively. A sharp decrease in solubility appeared when NaCl concentration was between 3% and 5%. These results showed that collagen from S. monotuberculatus had the type I collagen characteristics and good thermal stability, and therefore, it could be used as an alternative resource of collagen.

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Hierarchical nitrogen-doped porous graphene/carbon (NPGC) composites were fabricated by a simple and nontemplate method. The morphology characterizations demonstrate that reduced graphene oxide was successfully coated by the carbon derived from glucose, and a well-organized and interpenetrated hierarchical porous structure of NPGC was formed after pyrolysis at 950 °C. Notably, the prepared material, denoted as NPGC-950, has superlarge specific surface area (1510.83 m(2) g(-1)) and relatively high content percentage of pyridinic and graphitic nitrogen. As an efficient metal-free electrocatalyst, NPGC-950 exhibits a high onset potential (0.91 V vs RHE) and a nearly four-electron pathway for oxygen reduction reaction in alkaline solution as well as stronger methanol tolerance and better long-term durability than commercial Pt/C. In view of these excellent features, the obtained hierarchical N-doped metal-free porous carbon material is a promising catalyst for oxygen reduction reaction and could be widely applied in industry.

Recent Experimental Advanced Superconducting Tokamak (EAST) experiments have successfully demonstrated a long-pulse steady-state scenario with improved plasma performance through integrated operation since the last IAEA FEC in 2016. A discharge with a duration over 100 s using pure radio frequency (RF) power heating and current drive has been obtained with the required characteristics for future long-pulse tokamak reactors such as good energy confinement quality (H98y2 ~ 1.1) with electron internal transport barrier inside ρ  <  0.4, small ELMs (frequency ~100–200 Hz), and good control of impurity and heat exhaust with the tungsten divertor. The optimization of X-point, plasma shape, the outer gap and local gas puffing near the low hybrid wave (LHW) antenna were integrated with global parameters of BT and line-averaged electron density for higher current drive efficiency of LHW and on-axis deposition of electron cyclotron heating in the long-pulse operation. More recently, a high βP RF-only discharge (βP ~ 1.9 and βN ~ 1.5, /nGW ~ 0.80, f bs ~ 45% at q95 ~ 6.8) was successfully maintained over 24 s with improved hardware capabilities, demonstrating performance levels needed for the China Fusion Engineering Test Reactor steady-state operation. A higher energy confinement is observed at higher βP and with favorable toroidal field direction. Towards the next goal (⩾400 s long-pulse H-mode operations with ~50% bootstrap current fraction) on EAST, an integrated control of the current density profile, pressure profile and radiated divertor will be addressed in the near future.

Ovarian maturation in crustaceans is temporally orchestrated by two processes: oogenesis and vitellogenesis. The peptide hormone vitellogenesis-inhibiting hormone (VIH), by far the most potent negative regulator of crustacean reproduction known, critically modulates crustacean ovarian maturation by suppressing vitellogenin (VTG) synthesis. In this study, cDNA encoding VIH was cloned from the eyestalk of Pacific white shrimp, Litopenaeus vannamei, a highly significant commercial culture species. Phylogenetic analysis suggests that L. vannamei VIH (lvVIH) can be classified as a member of the type II crustacean hyperglycemic hormone family. Northern blot and RT-PCR results reveal that both the brain and eyestalk were the major sources for lvVIH mRNA expression. In in vitro experiments on primary culture of shrimp hepatopancreatic cells, it was confirmed that some endogenous inhibitory factors existed in L. vannamei hemolymph, brain, and eyestalk that suppressed hepatopancreatic VTG gene expression. Purified recombinant lvVIH protein was effective in inhibiting VTG mRNA expression in both in vitro primary hepatopancreatic cell culture and in vivo injection experiments. Injection of recombinant VIH could also reverse ovarian growth induced by eyestalk ablation. Furthermore, unilateral eyestalk ablation reduced the mRNA level of lvVIH in the brain but not in the remaining contralateral eyestalk. Our study, as a whole, provides new insights on VIH regulation of shrimp reproduction: 1) the brain and eyestalk are both important sites of VIH expression and therefore possible coregulators of hepatopancreatic VTG mRNA expression and 2) eyestalk ablation could increase hepatopancreatic VTG expression by transcriptionally abolishing eyestalk-derived VIH and diminishing brain-derived VIH.

The internal transport barrier (ITB) has been obtained in ELMy H-mode plasmas by neutron beam injection and lower hybrid wave heating on the Experimental Advanced Superconducting Tokamak (EAST). The ITB structure has been observed in profiles of ion temperature, electron temperature, and electron density within ρ<0.5. It was also observed that the ITB formation is stepwise. Due to the ITB formation, the confinement quality H 98y2 increases from 1 to 1.1 and the normalized beta, β N , increases from 1.5 to near 2. The fishbone activity observed during the ITB phase suggests the central safety factor q(0)∼1. Transport coefficients are calculated by particle balance and power balance analysis, showing an obvious reduction after the ITB formation.

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