Xu, Hai
Dong, Xing
Zhang, Zhen
Yang, Ming
Wu, Xiangyang
Liu, Hongcui
Lao, Qiaocong
Li, Chunqi
Highlights • DBP inhibits neutrophils formation in transgenic zebrafish embryos. • DBP inhibits macrophage formation and phagocytosis in zebrafish embryos. • DBP up-regulates the transcript levels of T cell-related gene. Abstract This study set out to understand the immune-toxic effects of dibutyl phthalate (DBP) using transgenic, albino or AB line zebrafish. Zebrafish embryos were exposed to different concentrations of DBP, and the immune cells formation, phagocytosis ability were measured after a short-term exposure to DBP for 6 h post-fertilization (hpf) to 72 or 96 hpf. Exposure to DBP was found to inhibit the neutrophils and macrophage formation in a concentration-dependent manner. The ability of macrophage phagocytosis was all decreased after exposure to DBP, indicating the occurrence of immunotoxicity. The respiratory burst was induced, and the transcription levels of T/B cell-related genes rag1/2 were up-regulated. The overall results indicate that DBP in aquatic environment greatly influence the immune system in fish, and zebrafish embryos can serve as a reliable model for the developmental immunotoxicity of toxic-chemicals.
Xu, Hai
Liu, Bin
Lan, Jianghu
Sheng, Enguo
Che, Shuai
Xu, Sheng
Knowledge of peatland initiation, accumulation, and decline or cessation is critical in understanding peatland development and the related carbon source/sink effect. In this study, we investigated the development of three peat profiles along the eastern margin of the Tibetan Plateau (ETP) and compared the results with those of our previous work along this transect. Our work showed that the initiation over the northern ETP is later and the slowdown/cessation earlier than in the middle to southern ETP. The timing of optimum peatland formation over the northern ETP lags the Holocene climatic optimum. These spatio-temporal differences are likely to be related to the intensity of Asian summer monsoon. Our work suggests that some peatlands along the ETP transect have returned or are now returning their previously captured carbon to the atmosphere and thus act as carbon sources. Some peatlands still have net accumulation at present, but the rates have been reduced concomitant with the decreasing summer monsoon intensity. We speculate that more of the previously stored carbon in the ETP peatlands will be re-emitted to the atmosphere if the aridity continues, as might occur under a continuous global-warming scenario. [All rights reserved Elsevier].
Xu, Hai
Hang, Lu Bin
Cai, Jin
Fu, Zhi Yu
Zhang, Peng Ju
Cheng, Wu Shan
Traditionally compliant mechanism is difficult to achieve decoupling features, because of lack of definite theory and its deformability character. Whereas its counterpart - many rigid mechanisms with decoupling property have been designed and the method of mechanism design with decoupling feature is constructed. In this paper, an effective method to build equivalent transformation between rigid decoupling mechanism and compliant mechanism with decoupling property is proposed, and also applied to design new a decoupling rigid mechanism with 3-DOF. Finally, the decoupling features of the micro motion platform was verified through FEM analysis software ANSYS because of difficulty of compliant mechanism analysis.