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Savanna is a widespread vegetation in dry-hot valley region, southwest China. However, the litterfall dynamic and their relations with meteorological factors are poorly understood. In the study, the litterfall dynamic of savanna ecosystem was monitored, and the relationships between litterfall dynamic and main meteorological factors were analyzed in Yuanjiang, Yunnan Province, southwest China. The results showed that the annual total litterfall yield was 2 142.7 kg⋅hm-2. Leaf litter accounted for 72.9% (1 561.5 kg⋅hm-2) of the total litterfall, and the branch, bark, flower & fruit, pieces were 284.9, 18.9, 172.4 and 105.0 kg⋅hm-2, which accounted for 13.3%, 0.9%, 8.1% and 4.9%, respectively. The monthly dynamic of litterfall yield showed mono-peak in October, namely, most plants shed leaves in October when the air temperature and precipitation decreased sharply. According to the correlation analysis with climate factors, the monthly litterfall productions were negatively correlated with mean air temperature, maximum air temperature, minimum air temperature, monthly precipitation and soil moisture content (P<0.01), which showed that monthly precipitation was the primary limiting factor affecting the monthly litterfall yield. [ABSTRACT FROM AUTHOR]

According to Split Hopkinson Pressure Bar (SHPB) test signal characteristic with high noise, short lasting time, mutant fast,the Hilbert-Huang transform (HHT) analysis technique was used to de-noise testing signal on the coal impact failure. The intrinsic mode function (IMF) components and its' frequency spectrum and the energy percentages of IMF components were got by using empirical mode decomposition (EMD) decomposition to measure coal impact damage SHPB test signal. Thus the high frequency noises were effectively separated out from the original signal by the low-pass filtering. Through the comparison of original signal and de-noised signal characteristic by using fast Fourier transform (FFT) spectrum and Morlet spectrum analysis, the qualitative conclusion that the HHT method could be used in coal impact damage SHPB testing signal de-noising were obtained. From the calculation of the denoised signal noise ratios and energy percentages, it was indicated that the de-noised signals were fully retained the signals' transient non-stationary featured and the de-noising effect was obvious by HHT method in quantitative description. The HHT method, which is applied for coal impact damage SHPB testing signal de-noising, is simple and can obtain reliable results. [ABSTRACT FROM AUTHOR]

Objective: To determine the effect of activation of specific anti-tumor cytotoxic T lymphocytes (CTL) and the ability of cross-presentation in vitro by fusion of HLA-A2+ human dendritic cells (DCs) with HLA-A2- melanoma cells., Methods: The HLA-A2+ human dendritic cells and HLA-A2- melanoma cells were fused by PEG and were cultivated in complete RPMI1640 media containing FCS (10%) and GM-CSF for 24-48 h, and then co-cultured fusion cells with Melan-A specific T cells. HLA-A2- melanoma cells were negative control,While T2 cells and DC+Pts were positive control. The activation of anti-tumor CTL elicited by the fusion cells was detected by intracellular cytokine staining., Results: The immature DC could express CD80, CD83, CD86, HLA-DR, and HLA-ABC,but the mature DC induced by TNF-alpha, PGE-2, and CD40L further highly expressed above molecules. The rate of specific CTL cells primed by the fusion cells was 16.72%+/-4.26%, negative control was 0.21%+/-1.84%,and positive control was 28.60%+/-5.67%. The CTL from vaccine by fusing DC and LAR6 induced lysis of HLA-A2+ LAR1 cells., Conclusion: The HLA-A2 restricted specific anti-tumor CTL can be induced in vitro by fusion of HLA-A2+ human dendritic cells with HLA-A2- melanoma cells.