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Objective The aims of this study were to investigate the antibiotic resistance, disinfectant resistance and their associations in 302 Salmonella enterica Typhimurium (S. Typhimurium) isolates from retail meats, food animals and humans. Methods Antibiotic susceptibility testing was performed according to the Kirby-Bauer disk diffusion method. The minimal inhibitory concentrations (MICs) of disinfectants were determined by broth microdilution method, and disinfectant resistance genes were detected by polymerase chain reaction (PCR) amplification. Results Antibiotic susceptibility testing demonstrated that 96.03% (290/302) of S. Typhimurium isolates were resistant to at least one antibiotic and 79.80% (241/302) were multidrug resistant (MDR). Tested isolates showed the highest resistance to streptomycin (78.81%, 238/302), followed by compound sulphonamides (78.15%, 236/302), tetracycline (75.50%, 228/302) and ampicillin (71.85%, 217/302). All isolates were sensitive to cefepime and imipenem. The resistance of S. Typhimurium from food to compound sulphonamides, tetracycline, ampicillin, nalidixic acid, and gentamicin were significantly higher than those from human and animal origin (P1 024 mg/L, respectively. In addition, the frequency of resistance to PVP-I, BC and TCS was observed significantly higher in food and animal isolates than human isolates (P

Based on the tectonic evolution and depositional characteristics of Central–West African Rift System and regional geologic background, the characteristics of oil and gas accumulation in the Termit rift superimposed basin were examined, and the factors controlling oil and gas accumulation there were discussed. The Termit basin is a rift superimposed basin formed by two stages of rifting in the early Cretaceous and Paleogene, where the Yogou Formation marine source rock is widespread. The two sets of reservoirs, the first member of the Paleogene Sokor Formation and the Cretaceous Yogou Formation, dominated by quartz sandstone, have relatively good porosity-permeability characteristics. They can form multiple sets of favorable caprock-reservoir assemblage below the regional caprock of the second member of Paleogene Sokor Formation. It is found that fault pattern and oil and gas migration pattern control the oil and gas accumulation patterns in the basin, including “Y-shaped” hydrocarbon migration and accumulation in the Araga graben, “multi-step” vertical hydrocarbon migration and accumulation in the Dinga faulted terrace, and the “composite” hydrocarbon migration and accumulation in the Fana transfer zone. Hydrocarbon enrichment in this basin was controlled by tectonic evolution of rift basins, that is, fault belts formed during the two stages of rifting controlled the horizontal distribution of oil and gas, while favorable reservoir-caprock assemblages in the sequences formed in the late rifting stage controlled the vertical hydrocarbon enrichment. Key words: Niger, Termit basin, rift superimposed basin, hydrocarbon accumulation, controlling factor

RGB-D image saliency detection refers to the addition of depth information in traditional 2D images to extract significant objects. However, for current saliency detection models, most of them focus on the saliency objects themselves, but ignore the background content. Therefore, this paper proposes a novel saliency detection model that takes depth information into consideration of both background and foreground to extract salient area. Firstly, the foreground noise is removed by the background measurement mechanism of the image boundary information and the background seed is selected from the boundary superpixels to calculate a background-based saliency map. Secondly, the input image is constructed into a graph, and the depth information is introduced into the graph. The foreground seeds are obtained by using clues such as color, depth and position, and the foreground-based saliency map is calculated. Finally, the background and foreground map are merged to obtain the initial saliency map, the cell optimization is performed, and the iterative propagation is performed to obtain the final saliency map. The comparison experiments are carried out on three RGB-D image saliency detection datasets LFSD, NJU-400 and NJU-2000. The experimental results show that the proposed method is effective and improves the accuracy.