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Oreocharis leveilleana Fedde was collected in Ta-pin in 1910 and published in 1911. The collected location was verified within western Luodian County, Guizhou Province, China. However, there have been no records of the species’ collection for more than 100 years since then. After extensive investigations by our research team on the type locality and its surrounding areas, we found that it is widely distributed in western Luodian County and eastern Wangmo County, Guizhou Province, China. During further research on the original literature, type specimens and type locality of O. leveilleana, the taxonomic position of O. leveilleana, which was once treated as a synonym of O. auricula (S.Moore) C.B.Clarke, was found to have a taxonomic problem. Through morphological research combined with geographical distribution analysis, it has been determined that it should belong to the genus Petrocodon Hance and it is the same species as P. coccineus (C.Y.Wu ex H.W.Li) Yin Z.Wang. According to the regulations and suggestions of the 2018 "International Code of Nomenclature for Algae, Fungi, and Plants (Shenzhen Code)", we propose and confirm a new combination – Petrocodon leveilleanus (Fedde) X.X.Bai & F.Wen and treat P. coccineus as a synonym of the new combination. Due to its unique bright red flowers within Petrocodon, its original Chinese name has been retained.

Many studies have demonstrated that arbuscular mycorrhizal fungi (AMF) and deficit irrigation (DI) have positive effects on the fruit yield or quality. This study aims to test whether the watermelon sugar content and yield can be improved by appropriate amounts of AMF and DI methods and to clarify the underlying physiological mechanism. Diploid and triploid watermelon cultivars and their pumpkin rootstock-grafted seedlings were treated with AMF, DI and DI + AMF in a randomised complete block design with five replications. The results showed that DI significantly reduced the relative water content (RWC), PN, alkaline α-galactosidase activity, but increased the insoluble acid invertase (IAI), sucrose synthase (SuSy) and sucrose phosphate synthase (SPS) activities compared with the well-watered (WW) treatment, which led to a decrease in the fruit yield and an increase in the fruit sugar content. Although the AMF improved the RWC, PN and alkaline α-galactosidase, IAI, SuSy and SPS activities in all the watermelon lines under both the DI and WW conditions, the improvement magnitude of these parameters was more pronounced in the pumpkin-root watermelon lines than the corresponding own-root watermelon lines, especially under the DI condition. The integrated application of AMF and DI increased the fruit yield to a level similar to the WW value in the pumpkin-root watermelon lines and sugar content to an optimal level in all the watermelon lines.

Two-phase flow (Gas-liquid) in pipelines is widely present in many fields, such as nuclear industry, chemical industry, and petroleum transportation. Compared with single-phase flow, the density, pressure, and momentum flux in two-phase flow change greatly in the flow. When flowing through a valve, elbows, tees, and other components, a pulsating force is induced, which is termed as the “flow-induced force.” Flow-induced force causes pipeline vibration. If the vibration frequency is close to the natural frequency of the pipeline, a resonance phenomenon occurs that can further increase the vibration amplitude of the pipeline and consequently cause fatigue damage to the pipeline system. Therefore, research on flow-induced force is of great significance for the safe design and operation of pipelines. In this paper, the research progress on the mechanism, influencing factors, and calculation models of flow-induced force was reviewed. The results show that the change of momentum flux is the dominant factor in causing flow-induced force. The pressure fluctuations, pulsation of the liquid slug, and the volatile liquid wave also contribute to force fluctuation. This study aims to establish a complete theoretical system of flow-induced force mechanism that shows varying wave characteristics with different flow patterns. Most of the current studies focus on single horizontal pipe or riser pipe. With the development of deep-sea oil and gas, demand on gathering and transportation-riser pipeline systems is increased, making it a great engineering significance to study the flow-induced force in a variety of pipeline-riser systems. The empirical and theoretical models are gradually established. The ability of CFD software to simulate flow field and excitation force offers numerous advantages. Therefore, research on the accuracy of CFD software calculation results and the comparison and optimization of effective CFD calculation simulation methods will have important scientific research value for development in the future. This article comprehensively summarized the current research status of gas-liquid two-phase internal flow excitation, which can provide guidance for further related research.

Many studies have demonstrated that brassinolide improves the drought tolerance of plants. This study aims to test whether the drought tolerance of chrysanthemums can be improved by brassinolide and to clarify the underlying physiological mechanism. An own-root chrysanthemum and a corresponding grafted-root line (Artemisia annua rootstock) were treated with brassinolide under three water levels in a randomised complete block design with five replications. The results showed that brassinolide increased the relative water content, net photosynthetic rate, chlorophyll (Chl) fluorescence parameters, Rubisco, ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase and monodehydroascorbate reductase activities, ascorbate/dehydroascorbate, glutathione/oxidised glutathione and dry mass, and reduced the H2O2 content in the own-root and grafted-root chrysanthemums, especially under drought stresses. The magnitude of the changes to the parameters was greater in the own-root line than in the corresponding grafted-root line under brassinolide treatment. The above parameters showed significant differences (P < 0.05) between the brassinolide chrysanthemums and the corresponding non-brassinolide chrysanthemums under drought stresses. This might be the physiological mechanism of improved drought tolerance by brassinolide in chrysanthemums. [ABSTRACT FROM AUTHOR]