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To correct the angular rate measurement error of MEMS gyroscopes for tactical missile, this paper proposes use of dynamics correspondence between the rudder control torque and the missile body attitude to build the state equation of system, which is more realistic and precise than the description for the actual missile attitude change with low-pass filter. In order to avoid errors in the linearization for nonlinear equations and reduce the filtering computation complexity, the Interlaced Kalman Filtering is applied to achieve the pseudo-linear state equation with coupling terms, which effectively reduce the computation complexity. Finally, the semi-physical simulation with the three-axis MEMS IMU and Electro-Servo verified that the algorithm significantly improved the angular rate measurement accuracy of the low-precision MEMS gyroscope.

In this study, the Agrobacterium tumefaciens-mediated transformation method for Ganderma weberianum has been established. Driven by the cauliflower mosaic virus (CaMV) 35S promoter, the hygromycin phosphotransferase (hpt), β-glucuronidase (uidA), and enhanced green fluorescent protein (egfp) genes have been efficiently expressed in transgenic mycelia and spores. The transformation system was composed of the growing mycelia, A. tumefaciens strain GV3101, and the expression vector pBI-H1, harboring the CaMV 35S promoter and selective hpt marker. The genetic transformation of G. weberianum was achieved through co-cultivation of Agrobacterium lawn and fungal mycelia at 28 °C on yeast extract agar (YEA) medium. Stable genetic transformants were obtained through successive hygromycin B selections and single spore isolation. Over 80 % of transformants showed genetic stability even after ten rounds of subculturing. The simple and efficient genetic transformation method is a useful tool for molecular genetics analyses and gene manipulation of G. weberianum.

Pancreatic cancer is notorious for its difficult diagnosis at early stage and poor recurrence-free prognosis. This study aimed to investigate the possible involvement of Oct4 and Nanog in pancreatic cancer. The high expressions of Oct4 and Nanog in human pancreatic cancer tissues were found to indicate a worse prognostic value of patients. The pancreatic cancer stem cells (PCSCs) that isolated from PANC-1 cell line by flow cytometry exhibited high expressions of Oct4 and Nanog. To investigate whether Oct4 and Nanog play crucial role in maintaining the stemness of PCSCs, double knockdown of Oct4 and Nanog demonstrated that Oct4 and Nanog significantly reduced proliferation, migration, invasion, chemoresistance, and tumorigenesis of PCSCs in vitro and in vivo. The altered expression of the genes related to pancreatic carcinogenesis, metastasis, drug resistance and epithelial-mesenchymal transdifferentiation (EMT) might affect the biological characteristics of PCSCs. Our results suggest that Oct4 and Nanog may serve as a potential marker of prognosis and a novel target of therapy for pancreatic cancer.

To explore the altered expressions of embryonic stem-related genes Oct4 and Nanog in pancreatic cancer stem cells (CSCs).The uni-cell suspension of human pancreatic cancer cell line PANC-1 was prepared and incubated with CD24 and CD44 antibodies. Flow cytometer was used to separate CD24(+)CD44(+) pancreatic cancer stem cells. Tumor cell spheres were observed under light microscope. Then CSCs were induced to differentiate with 10% fetal bovine serum and the expressions of CD24 and CD44 re-evaluated by flow cytometer. Finally the cells were divided into 2 groups, group 1: CD24(+)CD44(+) and group 2: non-separated group. RT-PCR (reverse transcription-polymerase chain reaction) and Q-PCR (quantitative-polymerase chain reaction) were used to examine the transcriptions of Oct4 and Nanog in CSCs. The immunofluorescence was employed to examine the expressions of Oct4 and Nanog. Chemo-sensitivity to gemcitabine was determined by CCK8 assay in each group.About 1%-3% CD24(+)CD44(+) CSCs were separated from cell line PANC-1. The sorted cells were cultured in a stem cell culture medium to observe the spheroid-forming capacity. And they showed a higher colony-forming efficiency than the unsorted cells [(122 ± 6)‰, P0.05]. When cultured in medium with serum, these cells gradually returned to the status of parental cells with a low expression of CD24 and CD44. Both Oct4 and Nanog were highly expressed in CD24(+)CD44(+) stem cells. And the CD24(+)CD44(+) subgroup demonstrated a higher resistance to gemcitabine.Subpopulation cells CD44(+)CD24(+) have the properties of tumor stem cells. The up-regulated levels of Oct4 and Nanog may be highly correlated with the multi-potency and a higher drug-resistance of pancreatic CSCs.