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Zeugodacus cucurbitae (Coquillett) is a highly damaging agricultural pest in many tropical and subtropical countries around the world and high temperatures usually affect its survival. To clarify the effect of short-term high temperatures on the survival and lifespan of Z. cucurbitae, newly emerged adults of three consecutive generations (F1, F2, and F3) were exposed to 25 °C, 33 °C, 37 °C, 41 °C, or 45 °C treatments for 1 h. The effect of these temperatures on survival and lifespan was evaluated using biological indicators such as lifespan and pupation rate. Then, to study the molecular regulatory mechanism of the lifespan of Z. cucurbitae after short-term high-temperature treatment, we exposed the newly emerged adults to 25 °C or 45 °C treatments for 1 h and used siRNA to interfere with the expression of the vitellogenin receptor (VgR) gene in the female to study the effect of the VgR gene on the lifespan of Z. cucurbitae. The results showed that the survival rate, lifespan, pupae weight, pupation rate, and emergence rate of Z. cucurbitae decreased with increased temperature, while the female sex ratio of offspring increased. The heat resistance of females was higher than that of males. Interference with the expression of the VgR gene resulted in shortening of the female’s lifespan by approximately 60% after exposure to 25 °C or 45 °C treatments for 1 h, which indicated involvement of the VgR gene in the regulation of Z. cucurbitae lifespan. This study provides a reference to guide integrated control of Z. cucurbitae in high-temperature seasons.

After running for about 59 000 h, the tubes at the intermediate mixing header of the furnace water wall leaked in an ultra-supercritical boiler. Preliminary analyses show that the primary crack may be initiated from two kinds of crack. One kind of crack is the dense transverse cracks in the external walls of the fireside, and the other one is the crack in adjacent H-shaped fin fillet weld. In order to figure out the initiation of the primary crack, the macroscopic morphology, chemical composition, microstructure, Vickers hardness and fracture morphology observation were conducted on the sample tube. The oriented dimples in the primary crack indicate that the crack propagates from the external side to the inner side. The erosive metal loss at fireside surfaces of tubes adjacent to the initial cracking shows significant differences. It is indicated that the primary crack is initiated from one side connected with the H-shape fin fillet weld crack. Based on comprehensive analyses of material quality of the sample tube and boiler operation data, it can be concluded that the wall temperature of water wall tubes changes with the frequent and large fluctuation of boiler load due to peak regulation operation, which is the root cause of fatigue cracking of H-shape fin fillet weld.

Big data in education is characterized by high dimensions, incompleteness and increment.In view of the characteristics of big data in education, in this paper, we propose: (1) incremental update algorithm of differential information based on incomplete decision table (2) design and construct MIX_FP tree to realize effective reduction of high-dimensional attributes. Experimental results verify that the algorithm has good operation efficiency and spatial performance, providing an effective method for attribute reduction of big data in education, and providing a new research idea for the research of attribute reduction algorithm based on rough set theory and its application in the field of learning and analysis.

Based on the data sources of OMI data and haze data in North China, this paper studies the spatial distribution characteristics of SO2 column amounts in North China from 2015 to 2017, and compares the relationship between SO2 column amounts and haze. Corresponding analysis reveals the objective regularity of its existence. The results revealed that: 1) spatially, the value of SO2 column is distributed higher in south and lower in north. In time, the amount of SO2 column is characterized by winter > autumn > spring > summer; 2) during the haze event, SO2 increased first and then decreased. The correlation analysis between the monthly average concentration of SO2 and the frequency of haze weather, showed that there is a high correlation between the SO2 concentration and the frequency of haze occurrence, and there is consistency in the space-time distribution; 3) The haze in North China is affected by meteorological and climatic factors and human activities. Coordination within the region is an important means to control air quality. To clarify the spatial and temporal distribution of SO2 during the haze weather in North China is conductive to smooth progress of haze events control in North China.

In this paper, the Cartesian products on fuzzy soft set are defined, and the fuzzy soft relations can be presented based on the Cartesian products, including uni-int decision relation and level fuzzy soft relation. By using these new concepts an unt-int decision making method based on fuzzy soft set is constructed to selects a fuzzy set of optimum elements from the alternatives. Finally, an example in reality is applied to illustrate the algorithm of the method successfully, and the validity also be discussed.