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In order to improve the lateral static stability of underwater glider under ocean current, premised on certain gliding efficiency, the appropriate hydrofoil swept angle and vertical tail aspect-ratio parameters are designed and numerical simulation method is used to analyze their influence on lateral static navigation performance under conditions of diving and floating. The results show that increasing the hydrofoil swept angle in a certain range has a positive effect on the lateral static stability of underwater glider in different gliding conditions, and increasing the vertical tail aspect-ratio has a dual effect on the lateral static stability in different gliding conditions. The method provides a theoretical basis for the design of hydrodynamic parameters of underwater glider sailing under different working conditions.

Underwater glider is developed for the application of marine variables observation by changing the net buoyancy as a driving force. It has many advantages, such as gliding with high efficiency, less power consumption, low noise, no pollution and so on. An accurate buoyancy adjusting method which used for underwater glider based on the volume change of interior gas is introduced in this paper. Besides, the buoyancy adjusting system using this method of the self-developed OUC underwater glider is described in detail. And we obtain the relation among the volume of external bladder, interior gas pressure and temperature by a measurement experiment. Finally, the comparative experiment between the interior calculation and the actual measurement of the volume of external bladder is performed simultaneously. The experimental results show that the buoyancy of glider can be accurately measured by the system, therefore successfully proving the validity of the buoyancy adjusting method.

The DNA methyltransferase (DNMT) inhibitory drugs such as 5-azacytidine induce DNA hypomethylation by inhibiting DNA methyltransferases. While clinically effective, DNMT inhibitors are not curative. A combination with cytotoxic drugs might be beneficial, but this is largely unexplored. In the present study, we analyzed potential synergisms between cytotoxic drugs and 5-azacytidine in acute myeloid leukemia (AML) and non-small cell lung cancer (NSCLC) cells. Lung cancer and leukemia cell lines were exposed to low doses of 5-azacytidine with varying doses of cytarabine or etoposide for AML cells (U937 and HL60) as well as cisplatin or gemcitabine for NSCLC cells (A549 and HTB56) for 48 h. Drug interaction and potential synergism was analyzed according to the Chou-Talalay algorithm. Further analyses were based on soft agar colony formation assays, active caspase-3 staining and BrdU incorporation flow cytometry. To identify effects on DNA methylation patterns, we performed genome wide DNA methylation analysis using 450K bead arrays. Azacytidine at low doses was synergistic with cytotoxic drugs in NSCLC and in AML cell lines. Simultaneous exposure to 5-azacytidine with cytotoxic drugs showed strong synergistic activity. In colony formation assays these synergisms were repeatedly verified for 5-azacytidine (25 nM) with low doses of anticancer agents. 5-azacytidine neither affected the cell cycle nor increased apoptosis. 450K methylation bead arrays revealed 1,046 CpG sites in AML and 1,778 CpG sites in NSCLC cells with significant DNA hypomethylation (24-h exposure) to 5-azacytidine combined with the cytotoxic drugs. These CpG-sites were observed in the candidate tumor-suppressor genes MGMT and THRB. Additional incubation time after 24-h treatment led to a 4.1-fold increase of significant hypomethylated CpG-sites in NSCLC cells. These results suggest that the addition of DNA demethylating agents to cytotoxic anticancer drugs exhibits synergistic activity in AML and NSCLC. Dysregulation of an equilibrium of DNA methylation in cancer cells might increase the susceptibility for cytotoxic drugs.

Song, D.; Guo, T.; Sun, W.; Jiang, Q., and Yang, H., 2018. Using an active disturbance rejection decoupling control algorithm to improve operational performance for underwater glider applications. The underwater glider is a large time-delaying, time-varying, nonlinear, and strong coupling control system that allows for various submarine environmental monitoring applications. To solve the coupling problem between pitch angle and velocity, improve control accuracy, and reduce settling time for energy consumption for the glider, a dynamic surface decoupling control (DSDC) algorithm based on the active disturbance rejection control (ADRC) is described in this paper. By importing the dynamic surface decoupling control law and first-order low-pass filter to improve control precision and reduce the number of calculations, a decoupling algorithm based on ADRC was used to solve the coupled control problem for an underwater glider. Combining the mathematical equation for motion and the kinematic equation f...

Underwater glider is a long-range autonomous underwater vehicle for oceanographic research that propels them through the ocean by changing their buoyancy. Balance parameters usually obtained through experiments. These kind of inaccurate parameters have a great influence on gliders gliding. In this article, a balance parameters calculation method of underwater glider based on BP neural network is presented. This study aims to find one of the most suitable balance parameters to improve the control effect of vehicles. Three steps are put forward to implement this approach. First, do at least two groups of pitch adjusting tests in the water and record the related data at the same time. Second, extract data and data preprocessing. Finally, use the BP Neural Network model to calculate balance parameters. The results of Qian-dao Lake test show that these parameters are appropriate and this calculation method is feasible. A further sea trial continues.