Hydrophobic coating is of great interest to enhance the corrosion resistance of magnesium alloy implants, which always suffer from rapid corrosion that leads to the failing application under physiological conditions. Plasma-polymerized fluorocarbon (C−F) coating has been widely studied as a substrate protection layer; however, the precise control of the deposition rate of C−F coating with fluorinated alkanes has been a challenge. In this study, a thin, uniform, pinhole-free, polymerlike, and hydrophobic C−F coating was successfully prepared using acetylene (C 2 H 2 ) as a crosslinking agent, which endows the coating with tunable properties of deposition rate by incorporation of unsaturated bonds. Electrochemical corrosion and in vitro immersion test demonstrated that the C−F coating significantly slows down the corrosion rate of MgZnMn in phosphate-buffered saline solution at 37 °C. Furthermore, an additional layer of PPAam was deposited on the C−F coating to eliminate the adverse effect of C−F surface on cytocompatibility. Thus, such a stacked coating imparts MgZnMn with a significantly improved corrosion resistance and promotes cell adhesion and viability. Therefore, the strategy of acetylenemediated C−F-based coating shows a great potential for tailoring ideal surface functionalities of magnesium-based medical devices.

The Lower Triassic Feixianguan (飞仙关) Formation oolitic shoal reservoir in the Sichuan (四川) basin (Southwest China) is currently an exploration and research highlight in China. The reservoir is widely believed to be formed mainly by burial dissolution and/or dolomitization on the basis of primary intergranular pores. In this study, through a comprehensive geological study on the whole basin, the dissolution and dolomitization are suggested not to be the fundamental factor of reservoir formation and there thus may be a possible new fundamental mechanism-the preservation of primary intergranular pores, i.e., the retention diagenesis. Based on this, a complex and multi-stage reservoir evolution and formation model is proposed. In the model, the depositional environment is the basis of reservoir initial formation. Subsequently, early compaction and shallow burial cementation result in the primary reservoir differentiation. Then, multi-stage burial dissolution alters and adjusts the reservoir. Because the last stage gaseous hydrocarbons have little diagenetic impact, the reservoir is formed finally. Therefore, this study presents a possible new fundamental mechanism and evolution model for the reservoir formation. The results can be applied in the regional reservoir predication and shaping exploration strategies, and provide reference for the study of shoal reservoirs in other areas. KEY WORDS: carbonate reservoir, oolitic shoal, primary intergranular pore, retention diagenesis, burial dissolution, dolomitization, Lower Triassic Feixianguan Formation, Sichuan basin.

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Background： The campaign to establish the national sanitary city has been launched across major places in Guizhou Province, which leads to the extensive use of insecticide to eradicate the disease-carrier Musca domestica found everywhere while keeping the cleanliness of environment.Methods: In order to perceive the resistance of houseflies to the commonly used organophosphate insecticides in 7 housefly populations belonging to Guizhou province (China), the susceptibility bioassays, detection of resistance-associated mutations, and the carboxylesterase activity assay were conducted.Results: The bioassays exhibited 142.16~303.54-fold to dichlorvos (DDVP) and 122.13~363.98-fold to temephos. The molecular analysis unveiled mutant ACE gene at loci of 260, 342 and 407 in all populations, which led to high frequencies at 27.4~73.8% of 260L, 59.1~76.7% of 342A, 23.7~40.9% of 342V, and 83.4~100.0% of 407Y, with inclusion of 8 genotypes and 10 mutant combinations. Further analysis of mutations showed a linkage disequilibrium of L/V+A+Y at locus 260 & 342, indicating a significant association with the DDVP resistance. The Hardy-Weinberg equilibrium test demonstrated that the observed ACE heterozygosity mostly exceeded 0.5 and deviated from the equilibrium. In the fixation index, an insignificant differentiation was noted among the 7 housefly populations. Conclusions: However, further research should concentrate on the use of insecticides to avoid the abuse of insecticides, and to regularly monitor the resistance of houseflies using novel methods.

Link prediction for complex networks is a research hotspot. The main purpose is to predict the unknown edge according to the structure of the existing network. However, the edges in realworld networks are often sparsely distributed, and the number of unobserved edges is usually far greater than that of observed ones. Considering the weak performance of traditional link prediction algorithms under the above situation, this paper puts forward a novel link prediction algorithm called network adjacency matrix blocked-compressive sensing (BCS). Firstly, the diagonal blocks were subjected to sparse transformation with the network adjacency matrix; Next, the measurement matrix was rearranged into a new measurement matrix using the sorting operator; Finally, the subspace pursuit (SP) algorithm was introduced to solve the proposed algorithm. Experiments on ten real networks show that the proposed method achieved higher accuracy and consumed less time than the baseline methods.