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The intelligent combat of aircraft has become an important research area. This paper studies the 1Vs1 pursuit-evasion game confrontation scenario of the aircraft, aiming to enable the red agent to find the optimal strategy to avoid the blue interception. First, the aircraft is abstracted into an agent, the kinematics model of the aircraft is simplified, and the behavior model of the aircraft with the bait throwing behavior is established. Based on the improved DQN algorithm, with relative distance, line-of-sight angle and azimuth as the state; the reward function design comprehensively considers the time, number of bait throwing, maneuvering time, and miss distance, and proposes an aircraft pursuit-evasion game algorithm (RB-DQN) in a three-dimensional environment. Experimental results show that the algorithm can effectively control the aircraft to complete the escape mission, and has satisfactory generalization.

White clover widely cultivated in China is one of the most important perennial leguminous forages in temperate and subtropical regions. There is a large quantity of white clover seeds imported into China each year for demands of high-quality grass seeds. Seedborne diseases may cause significant economic losses. DNA sequencing technologies allow for the direct estimation of microbial community diversity, avoiding culture-based biases. Therefore, we used 16S rRNA gene sequencing to investigate the bacterial communities in white clover seeds collected from four different countries. The results showed that a total of 484,715 clean reads were obtained for further subsequent analysis. In total, 341, 340, 382, and 297 operational taxonomic units were obtained at 3% distance cutoff in DB, MB, TB, and XB samples, respectively. The richness indexes revealed that TB sample from Argentina had the highest bacterial richness in four samples. Our results demonstrated that Proteobacteria was the dominant phyla in MB, TB, and XB; however, Bacteroidetes was the dominant phyla in DB. The dominant genus of DB was Prevotella (11.9%), while Sphingomonas was the major genus of MB (46.9%), TB (55.08%), and XB (47.2%) samples. These results provide useful information for seedborne diseases and transmission of bacteria from seed to seedling.

Adonis palaestina Boiss. is one of the top three natural sources of red pigment astaxanthin, which has been used as a valuable antioxidant nutraceutical and a feed additive for salmonid fish raising. Since 2004, a blight disease causing significant damage to plants of A. palaestina in Inner Mongolia, China has occurred. The disease caused small, brown lesions on petioles and stems of the host plants. The disease initially appeared in the field as a brown necrosis on lower parts of the plant, and eventually expanded to the whole plant resulting in complete defoliation. The fungus consistently isolated from symptomatic tissues was identified as Phoma adonidicola based on morphological characteristics. Phylogenetic analysis based on LSU (Large Subunit - 28S), ITS (ITS1-5.8S-ITS2 region), and TUB (β-tubulin) showed that the P. adonidicola isolates fall in the same well-supported clade, which is closely related to Stagonosporopsis ajacis. All isolates of P. adonidicola also caused typical spots on inoculated plants, and were successfully reisolated from the symptomatic tissues. The disease of A. palaestina was proposed as spot blight.

We develop a micro-pipette tip-based nucleic acid test (MTNT) for high-throughput sample-to-answer detection of both DNA and RNA from crude samples including cells, bacteria, and solid plants, without the need of sample pretreatment and complex operation. MTNT consists of micro-pipette tips and embedded solid phase nucleic acid extraction membranes, and fully integrates the functions of nucleic acid extraction from crude samples, loop-mediated isothermal amplification (LAMP) of nucleic acids, and visual readout of assays. The total assaying time for DNA or RNA from a variety of crude samples ranges from 90 to 160 min. The limit of detection (LOD) of MTNT is 2 copies of plasmids containing the target nucleic acid fragments of Ebola virus, and 8 CFU of Escherichia coli carrying Ebola virus-derived plasmids. MTNT can also detect CK-19 mRNA from as few as 2 cancer cells without complicated procedures such as RNA extraction and purification. We further demonstrate MTNT in a high-throughput format using an eight-channel pipette and a homemade mini-heater, with a maximum throughput of 40 samples. Compared with other point-of-care (POC) nucleic acid tests (NAT), MTNT could assay both DNA and RNA directly from liquid (cells/bacteria/blood) or solid (plant) samples in a straightforward, sensitive, high-throughput, and containment-free manner, suggesting a considerable promise for low-cost and POC NAT in remote areas.

Structural evolution of bulk undercooled Ni–11.56 at.% Pb monotectic alloy was investigated systematically by using molten glass denucleating combined with superheating cycling. Within the achieved undercooling range 10–286 K, the solidification structures were classified into three categories. When the undercooling was less than 50 K, the structures consisted of coarse dendrites and interdendritic lead phase. With the undercooling increasing into the range of 70–232 K, the dendrite clusters were refined and fine lead particles separated out from the supersaturated primary dendrite arms because of solute trapping. When the undercooling exceeded 242 K, the granular grains formed and fine lead particles homogeneously distributed in the whole sample. The phase selection of high temperature melts was analyzed by adopting steady state nucleation theory. The calculated results shown that undercooled Ni–11.56 at.% Pb monotectic alloy melts solidified in the form of α (Ni) dendrites essentially during the stage of rapid solidification and after recalescence, the interdendritic residual melts solidified in the equilibrium mode. Based on the observation of the solidification structures and the calculated results with BCT dendritic growth model, it was confirmed that the granulation mechanism of the granular grains was owing to the primary dendritic disintegration and subsequent recrystallization.