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Summary An innovative small transportable lead‐bismuth cooled fast reactor, named SPARK, with rated power of 20 MWth is proposed to operate for 20 years without refueling as a remote power supply. The SPARK core neutronics and thermal‐hydraulics design and preliminary safety analysis were performed in the current study. In order to achieve a compact and light‐weight core design with enhanced transportability and passive safety, the selection of reflector materials, the optimization of fuel assembly design and radial core zoning loading, and the reactivity control system design were accomplished. MgO was selected as the optimal reflector material due to its good neutron reflecting characteristics and low density. The fuel assembly design was optimized to obtain a long lifetime of core and low peak cladding surface temperature. To flatten radial power distribution, 3 radial zones were designed with different fuel pin diameters. A liquid absorber control system was implemented using 6Li‐enriched liquid lithium as the neutron absorber, which significantly reduces the core height. To reduce the initial excess reactivity, fixed absorbers were installed in the scram assemblies for the first half life and then replaced by fixed reflectors for the second half life. Based on the parametric study, the optimized core design was determined, and the core neutronics and thermal‐hydraulics performances were evaluated. The objective core lifetime of 18 effective full power years was fulfilled with the compact and light‐weight core design, and the thermal design constraints were satisfied during the whole life. Both the control and scram systems proved to independently provide sufficient shutdown margins. Using the quasi‐static reactivity balance method, the passive safety characteristics of the optimized core design were analyzed based on 5 anticipated transients without scram. Passive shutdown was achieved due to the negative reactivity feedback. The critical design constraint of the peak cladding surface temperature was satisfied for all transients.

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long noncoding rnas regulate the occurrence and progression of numerous types of cancer, including bladder cancer (Bca). However, the role of long intergenic non-protein coding rna 978 (linc00978) in Bca remains unknown. In the present study, it was identified that the LINC00978 expression level was significantly increased in BCa tissues compared with adjacent normal tissues. By performing cell proliferation, colony formation, Transwell and Matrigel assays, it was demonstrated that LINC00978 knockdown significantly inhibited the proliferation, migration and invasion of Bca cells. conversely, overexpression of linc00978 resulted in opposite effects. Mechanistically, it was demonstrated that linc00978 served as a competing endogenous rna to sponge microrna-4288 (mir-4288), and linc00978 knockdown significantly increased the expression level of miR-4288 in BCa cells. Furthermore, it was demonstrated that the expression of linc00978 was inversely correlated with the mir-4288 expression level in Bca tissues. Furthermore, by performing a rescue assay, it was identified that inhibition of miR-4288 was able to reverse the effects of linc00978 knockdown on proliferation, migration and invasion of Bca cells. collectively, the present study demonstrated that linc00978 promoted Bca progression by sponging mir-4288, suggesting that linc00978 may represent a potential therapeutic target for Bca treatment.