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Despite the importance of circadian rhythms in insect behavior, our understanding of circadian activity and the molecular oscillatory mechanism in parasitoid wasp circadian clocks is limited. In this study, behavioral activities expected to be under the control of the endogenous circadian system were characterized in an ectoparasitoid wasp, Pachycrepoideus vindemmiae. Most adults exhibited emergence between late night and early morning, while mating only occurred during the daytime, with a peak at midday. Oviposition had three peaks in the early morning, late day, or early night and late night. Additionally, we identified eight putative clock genes from P. vindemmiae. The quantitative PCR (qPCR) results indicate that most clock genes showed significant rhythmic expressions. Our comparative analysis of clock genes in P. vindemmiae and 43 other parasitoid wasps revealed that none of the wasps possessed the timeless and cry1 genes commonly found in some other insect species, suggesting that the circadian clock system in parasitoid wasps is distinct from that in other non-Hymenoptera insects such as Drosophila. Thus, this study attempted to build the first hypothetical circadian clock model for a parasitoid wasp, thus generating hypotheses and providing a platform for the future functional characterization of P. vindemmiae clock genes as well as those of other parasitoid wasps. Finally, these findings on P. vindemmiae circadian activity will aid the development of effective field release programs for biological control, which can be tested under field conditions.

In ultrasonic vibration assisted grinding (UAG) along the axial direction, the machining process of an abrasive grit is introduced in this paper. During the internal UAG, the critical speed is determined by the amplitude and frequency of ultrasonic vibration. During the surface UAG, the cutting model of an abrasive grit is established and the cutting trace length of an abrasive grit and the grinding force making chips deformation is analyzed in theory. The analysis results show that the cutting trace length is longer by introducing ultrasonic vibration along the axial direction; the grinding force is decreased, the higher vibration amplitude and frequency is helpful to the decrease of the grinding force and the higher grinding wheel speed weakens the contributiveness of ultrasonic vibration to the decrease of the grinding force.

In order to achieve the precise control of the compressed air foam proportioning on the fire engines, in this paper, the PIC microcontroller and the fuzzy control algorithm are used to design the microcontroller-based foam proportioning hybrid fuzzy control system. Taking into account the system cost and ease, we use the software to implement the fuzzy control of DC motor. The controller learns from the experience of skilled operators, and forms fuzzy control rules, finally we identify a number of important control parameters in this paper. The experimental results show that the fuzzy control system can achieve precise control of the mixing ratio