AUV-Aided Optical-Acoustic Hybrid Data Collection Based on Deep Reinforcement Learning.

Autonomous underwater vehicles (AUVs)-assisted mobile data collection in underwater wireless sensor networks (UWSNs) has received significant attention because of their mobility and flexibility. To satisfy the increasing demand of diverse application requirements for underwater data collection, such as time-sensitive data freshness, emergency event security as well as energy efficiency, in this paper, we propose a novel multi-modal AUV-assisted data collection scheme which integrates both acoustic and optical technologies and takes advantage of their complementary strengths in terms of communication distance and data rate. In this scheme, we consider the age of information (AoI) of the data packet, node transmission energy as well as energy consumption of the AUV movement, and we make a trade-off between them to retrieve data in a timely and reliable manner. To optimize these, we leverage a deep reinforcement learning (DRL) approach to find the optimal motion trajectory of AUV by selecting the suitable communication options. In addition to that, we also design an optimal angle steering algorithm for AUV navigation under different communication scenarios to reduce energy consumption further. We conduct extensive simulations to verify the effectiveness of the proposed scheme, and the results show that the proposed scheme can significantly reduce the weighted sum of AoI as well as energy consumption.

Effect of Powder on Tribological and Electrochemical Properties of Nylon 66 and Ultra-High Molecular Weight Polyethylene in Water and Seawater Environments.

Polymer materials are used increasingly in marine machinery and equipment; their tribological properties and effect on the water environment have garnered significant attention. We investigate the effect of water or seawater environment containing powder on tribology and electrochemistry of polymer materials. A friction test involving nylon 66 (PA66) and an ultrahigh molecular weight polyethylene (UHMWPE) pin-disc (aluminum alloy) is performed in seawater or water with/without polymer powder, and the solution is analyzed electrochemically. The results show that the tribological properties of the UHMWPE improved by adding the powder to the solution, whereas the PA66 powder demonstrates abrasive wear in a pure water environment, which elucidates that the synergistic effect of powder and seawater on UHMWPE reduces the wear, and the synergistic effect of pure water and powder aggravates the wear. The results of electrochemical experiments show that after adding powder in the friction and wear tests, the powder can protect the pin by forming a physical barrier on the surface and reducing corrosion, and the changes are more obvious in seawater with powder in it. Through electrochemical and tribological experiments, the synergistic effect of solution environment and powder was proved.

LncRNA LINC00958 Activates mTORC1/P70S6K Signalling Pathway to Promote Epithelial-Mesenchymal Transition Process in the Hepatocellular Carcinoma.

The study aimed to investigate the influence of LINC00958 on the EMT process of hepatocellular carcinoma (HCC). In our study, The LINC00958 was up-regulated in HCC tissues and cell lines. LINC00958 silencing inhibited cell proliferation, migration, and EMT process of HCC. The analysis of TCGA and StarBase showed that NUDT19 was a direct target of LINC00958 and was positively regulated by LINC00958. Besides, NUDT19 activated mTORC1/P70S6K signalling pathway. Both NUDT19 overexpression and mTORC1 activator MYH1485 reversed the inhibitory effect of LINC00958 silencing on proliferation, migration, and EMT process of HCC. In conclusion, LINC00958 silencing inhibited the proliferation, migration, and EMT process of HCC via inhibiting NUDT19 mediated mTORC1/P70S6K signalling pathway.

Changes in peripheral blood inflammatory factors (TNF-α and IL-6) and intestinal flora in AIDS and HIV-positive individuals.

OBJECTIVE: In this study, we investigated the changes in peripheral blood inflammatory factors and intestinal flora in acquired immune deficiency syndrome (AIDS) and human immunodeficiency virus (HIV)-positive individuals (AIDS/HIV patients), and explored the relationships among intestinal flora, peripheral blood inflammatory factors, and CD4+ T lymphocytes. METHODS: Thirty blood and stool samples from an AIDS group and a control group were collected. The levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were determined by enzyme-linked immunosorbent assay (ELISA), and the number of CD4+ T lymphocytes by a FACSCount automated instrument. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the messenger RNA (mRNA) levels of Bifidobacterium, Lactobacillus, Escherichia coli, Enterococcus faecalis, and Enterococcus faecium. Correlations among intestinal flora, inflammatory factor levels, and CD4+ T lymphocyte values were evaluated using the Spearman correlation coefficient. RESULTS: The levels of TNF-α and IL-6 in the AIDS group were higher than those in the control group, while the number of CD4+ T lymphocytes was lower. The amounts of Bifidobacterium and Lactobacillus in the AIDS group were significantly lower than those in control group, while the amounts of E. coli, E. faecalis, and E. faecium were much higher. The amounts of Bifidobacterium and Lactobacillus were negatively correlated with the content of TNF-α and IL-6 and the CD4+ T lymphocyte count, while those correlations were reversed for E. coli, E. faecalis, and E. faecium. CONCLUSIONS: The intestinal microbiota of AIDS/HIV patients were disordered, and there was a correlation between the amount of intestinal flora and the number of CD4+ T lymphocytes and the levels of TNF-α and IL-6.