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Artemisinin resistance in Plasmodium falciparum threatens the remarkable efficacy of artemisinin-based combination therapies worldwide. Thus, greater insight into the resistance mechanism using monitoring tools is essential. The ring-stage survival assay is used for phenotyping artemisinin-resistance or decreased artemisinin sensitivity. Here, we review the progress of this measurement assay and explore its limitations and potential applications.

The isotope Xe-135 has a large thermal neutron absorption cross section and is considered to be the most important fission product. A very small amount of such neutron poison may significantly affect the reactor reactivity since they will absorb the neutrons from chain reaction, therefore monitoring their atomic density variation during reactor operation is extremely important. In a molten reactor system, Xe-135 is entrained in the liquid fuel and continuously circulates through the core where the neutron irradiation functions and the external core where only nuclei decay occurs, at the same time, an off-gas removal system operates for online removing Xe-135 through helium bubbling. These unique features of MSR complicate the Xe-135 dynamic behaviors, and the calculation method applied in the solid fuel reactor system is not suitable. From this point, we firstly analytically deduce the nuclei evolution law of Xe-135 in the flowing salt with an off-gas removal system functioning. A study of Xe-135 dynamic behavior with the core power change, shutdown, helium bubbling failure and startup then is conducted, and several valuable conclusions are obtained for MSR design.

MSR (Molten salt reactor) is a reactor with the fission material dissolved in the fluoride salt as the fuel, which continuously circulates through the primary loop. The liquid fuel makes the online refueling and reprocessing be possible, consequently, more fuel cycle options would be presented due to the introduction of various refueling fuel type and reprocessing mode (continuous / batch reprocessing) comparing with that of the solid fuel reactor systems. It is important to evaluate all the possible fuel cycle options and screen out the promising ones to narrow the R&D activities of TMSR (Thorium-based Molten-Salt Reactor nuclear energy system) program. In this study, we firstly established a screening and decision-making framework, then conducted an initial evaluation work and identified the potential promising fuel cycle options. Synthesizing the goal of TMSR program and technology readiness, we proposed a “Three-steps” fuel cycle development strategy with the aim for gradually increasing the thorium resource utilization while considering the challenges of the reprocessing technology.