A Seakeeping Analysis Method for T-Craft

AbstractThe Transformable-Craft (T-Craft) is an innovative vessel serving as a connector between sea base and beachheads. When operatingat seas, the T-Craft is a surface effect ship (SES) with compartmented air cushions. To analysis the seakeeping performance of the T-Craft SES, a high efficient 2D/2.5D analytical model has been developed by combining the one dimensional waveequation for solving aerodynamics of pressurized cushion air with the STF/2.5D method for solving hydrodynamics of demihulls at low/high speeds. To enhance the computational efficiency, the entire model is linearized except the dynamics of air leakage, which is strongly nonlinear and inappropriate for linearization. Results obtained from the proposed seakeeping analysis model show reasonable agreement with experimental data, while the proposed model hascompetitiveness in the computational efficiency as compared with some 3D models from public works

High-Order Sliding Mode-Based Synchronous Control of a Novel Stair-Climbing Wheelchair Robot

For the attitude control of a novel stair-climbing wheelchair with inertial uncertainties and external disturbance torques, a new synchronous control method is proposed via combing high-order sliding mode control techniques with cross-coupling techniques. For this purpose, a proper controller is designed, which can improve the performance of the system under conditions of uncertainties and torque perturbations and also can guarantee the synchronization of the system. Firstly, a robust high-order sliding mode control law is designed to track the desired position trajectories effectively. Secondly, considering the coordination of the multiple joints, a high-order sliding mode synchronization controller is designed to reduce the synchronization errors and tracking errors based on the controller designed previously. Stability of the closed-loop system is proved by Lyapunov theory. The simulation is performed by MATLAB to verify the effectiveness of the proposed controller. By comparing the simulation results of two controllers, it is obvious that the proposed scheme has better performance and stronger robustness

Smooth Muscle-specific Expression of Calcium-independent Phospholipase A2 (iPLA2 ) Participates in the Initiation and Early Progression of Vascular Inflammation and Neointima Formation

Background: The role of iPLA 2 β as a regulator of inflammatory signaling and neointima formation is unknown. Result: Smooth muscle-specific expression of iPLA 2 β exacerbates proinflammatory cytokine production, macrophage infiltration, and neointima formation. Conclusion: Smooth muscle-specific iPLA 2 β participates in the initiation and early progression of vascular inflammation and neointima formation. Significance: iPLA 2 β may represent a novel therapeutic target for attenuating vascular inflammation and restenosis

Mastering Complex Control in MOBA Games with Deep Reinforcement Learning

We study the reinforcement learning problem of complex action control in the Multi-player Online Battle Arena (MOBA) 1v1 games. This problem involves far more complicated state and action spaces than those of traditional 1v1 games, such as Go and Atari series, which makes it very difficult to search any policies with human-level performance. In this paper, we present a deep reinforcement learning framework to tackle this problem from the perspectives of both system and algorithm. Our system is of low coupling and high scalability, which enables efficient explorations at large scale. Our algorithm includes several novel strategies, including control dependency decoupling, action mask, target attention, and dual-clip PPO, with which our proposed actor-critic network can be effectively trained in our system. Tested on the MOBA game Honor of Kings, our AI agent, called Tencent Solo, can defeat top professional human players in full 1v1 games.Comment: AAAI 202

Helicobacter pylori infection increases the risk of thyroid nodules in adults of Northwest China

BackgroundThyroid nodules (TNs) are very common in the adults of Northwest China. The role of Helicobacter pylori (H. pylori) infection in TNs is poorly investigated and even with controversial conclusions. Our study aimed at highlighting the relationship between H. pylori infection and the risk of TNs.Methods9,042 individuals were enrolled with thyroid ultrasonography and 14C-urea breath test (14C-UBT). Baseline characteristics and relevant covariates were obtained, including basic and laboratory indicators. After applying the exclusion criteria, 8,839 patients were included and divided into 2 groups: a cross-sectional study of single follow-up (n=8,711) and a retrospective cohort study of multiple follow-ups for 5 years (n=139).ResultsThe prevalence of H. pylori infection and TNs was 39.58% and 47.94% in the adults of Northwest China, respectively. The prevalence of TNs was significantly higher among H. pylori-positive individuals than those without infection (52.55% vs. 44.92%, p<0.01). The result of binary logistic regression revealed that the crude odds ratio (OR) was 1.624 (95% CI 1.242~2.123) in Model 1 without adjustment compared to H. pylori-negative group, and was also positive in Model 2, 3, and 4 (Model 2: OR=1.731, 95% CI 1.294~2.316; Model 3: OR=2.287, 95% CI 1.633~3.205; Model 4: OR=2.016, 95% CI 1.390~2.922) after the adjustment. The data of 5-year follow-up showed that the annual incidence of TNs was significantly higher in individuals with persistent H. pylori infection than non-infected counterparts (all p<0.05).ConclusionsH. pylori is an independent risk factor for TNs in the adults of Northwest China

Overexpression of a MYB Family Gene, OsMYB6, Increases Drought and Salinity Stress Tolerance in Transgenic Rice

MYB transcription factors have been demonstrated to play key regulatory roles in plant growth, development and abiotic stress response. However, knowledge concerning the involvement of rice MYB genes in salinity and drought stress resistance are largely unknown. In the present study, we cloned and characterized the OsMYB6 gene, which was induced by drought and salinity stress. Subcellular localization of OsMYB6-YFP fusion protein in protoplast cells indicated that OsMYB6 was localized in the nucleus. Overexpression of OsMYB6 in rice did not suggest a negative effect on the growth and development of transgenic plants, but OsMYB6-overexpressing plants showed increased tolerance to drought and salt stress compared with wild-type plants, as are evaluated by higher proline content, higher CAT and SOD activities, lower REL and MDA content in transgenic plants under drought and salt stress conditions. In addition, the expression of abiotic stress-responsive genes were significantly higher in OsMYB6 transgenic plants than that in wild-type plants under drought and salt stress conditions. These results indicate that OsMYB6 gene functions as a stress-responsive transcription factor which plays a positive regulatory role in response to drought and salt stress resistance, and may be used as a candidate gene for molecular breeding of salt-tolerant and drought-tolerant crop varieties

Air cushion barge platform for offshore wind turbine and its stability at a large range of angle

One of typical bases for floating offshore wind turbines is the barge platform that has merits of simpler structure and lower costs, but disadvantages of significant responses in waves. In order to improve the hydrodynamic performance of the barge platforms, in this paper a novel Air cushion Barge Platform (ACBP) is proposed, into which multiple air chambers are incorporated to mitigate the wave loads and reduce the dynamic motions due to waves. However, the existing analytical method is not suitable for evaluating the righting moment and stability of the ACBP at large angles. To address this issue, a new analytical method is developed, which can be used to quickly calculate its righting moment and evaluate its stability in the whole range of trim angles, including very large one with possible emergence of the platform bottom and so with air leakage from a few chambers before capsized. The newly proposed analytical method is calibrated by the CFD results, and then is employed for investigating the static and dynamic stability of the ACBP for two typical designs

Identification and Characterization of the Lamprey High-Mobility Group Box 1 Gene

High-mobility group box 1 (HMGB1), a highly conserved DNA-binding protein, plays an important role in maintaining nucleosome structures, transcription, and inflammation. We identified a homolog of HMGB1 in the Japanese lamprey (Lampetra japonica). The Lampetra japonica HMGB1 gene (Lj-HMGB1) has over 70% sequence identity with its homologs in jawed vertebrates. Despite the reasonably high sequence identity with other HMGB1 proteins, Lj-HMGB1 did not group together with these proteins in a phylogenetic analysis. We examined Lj-HMGB1 expression in lymphocyte-like cells, and the kidneys, heart, gills, and intestines of lampreys before and after the animals were challenged with lipopolysaccharide (LPS) and concanavalin A (ConA). Lj-HMGB1 was initially expressed at a higher level in the heart, but after treatment with LPS and ConA only the gills demonstrated a significant up-regulation of expression. The recombinant Lj-HMGB1 (rLj-HMGB1) protein bound double-stranded DNA and induced the proliferation of human adenocarcinoma cells to a similar extent as human HMGB1. We further revealed that Lj-HMGB1 was able to induce the production of tumor necrosis factor-α (TNF-α), a pro-inflammatory mediator, in activated human acute monocytic leukemia cells. These results suggest that lampreys use HMGB1 to activate their innate immunity for the purpose of pathogen defense