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Long- distance migrations of insects contribute to ecosystem functioning but also have important economic impacts when the migrants are pests or provide ecosystem services. We combined radar monitoring, aerial sampling, and searchlight trapping, to quantify the annual pattern of nocturnal insect migration above the densely populated agricultural lands of East China. A total of -9.3 trillion nocturnal insect migrants (15,000 t of biomass), predominantly Lepidoptera, Hemiptera, and Diptera, including many crop pests and disease vectors, fly at heights up to 1 km above this 600 km- wide region every year. Larger migrants (>10 mg) exhibited seasonal reversal of movement directions, comprising northward expansion during spring and summer, followed by southward movements during fall. This north-south transfer was not balanced, however, with southward movement in fall 0.66- that of northward movement in spring and summer. Spring and summer migrations were strongest when the wind had a northward component, while in fall, stronger movements occurred on winds that allowed movement with a southward component; heading directions of larger insects were generally close to the track direction. These findings indicate adaptations leading to movement in seasonally favorable directions. We compare our results from China with similar studies in Europe and North America and conclude that ecological patterns and behavioral adaptations are similar across the Northern Hemisphere. The predominance of pests among these nocturnal migrants has severe implications for food security and grower prosperity throughout this heavily populated region, and knowledge of their migrations is potentially valuable for forecasting pest impacts and planning timely management actions. [ABSTRACT FROM AUTHOR]

To suppress the agglomeration of bare CoNi2S4 during the charging and discharging process, herein, Baoqing lignite has been utilized as the raw material, extracted with KOH and melamine solution, and annealed to nitrogen-doped lignite-based porous carbon (NPC), which was subsequently composited with CoNi2S4 by a facile and efficient hydrothermal method. In the CoNi2S4/nitrogen-doped lignite-based porous carbon composites (CoNi2S4/NPC), CoNi2S4 particles are uniformly dispersed on NPC. The as-prepared CoNi2S4/NPC have displayed excellent electrochemical properties with high specific capacitance and good cycle performance. The composites possess a high specific capacitance of 1534.24 F g−1 at a current density of 4 A g−1. The hybrid supercapacitor assembled by the CoNi2S4/NPC cathode and the activated carbon anode has demonstrated a high energy density of 48.58 Wh kg−1 at 400 W kg−1. Moreover, the capacitance retention of the hybrid supercapacitor is 82.42% after 5000 cycles. [ABSTRACT FROM AUTHOR]

Spodoptera frugiperda is a major agricultural pest that has invaded China since January 2019. Given that most of the individuals present in China carried the diagnostic rice-strain mtDNA (COI -RS), there was no efficient method to distinguish populations of S. frugiperda. In this study, we identified and characterized two variant microsatellite alleles in the mitochondrial NAD6 gene of S. frugiperda retrieved from the National Center for Biotechnology Center GenBank. We then sequenced partial NAD6 genes containing the microsatellite region and the diagnostic COI barcoding gene (used to distinguish the corn-strain and the rice-strain) of 429 invasive S. frugiperda individuals that were collected from the main infested regions in China during 2019–2020. Our data indicates that two kinds of interrupted repeat sequences, (ATA)4T(ATA)3 and (ATA)5T(ATA)3, exist in the microsatellite region which we defined as the deletion type (NAD6 -D), and the insertion type (NAD6 -I) based on the repeat units' differentiation, respectively. The presence of these two microsatellite types in the mtDNA genome of S. frugiperda was further confirmed with the sequencing results in 429 samples. Moreover, NAD6 -I and NAD6 -D types were both present in individuals with COI -RS, while only NAD6 -D type was detected in the COI -CS individuals. Interestingly, the two microsatellite types suggested a possible geographic distribution: the western migratory route (Yunan and Chongqing) was comprised exclusively of NAD6 -I type, while both NAD6 -I and NAD6 -D types were identified in the predicted eastern migration trajectories (Hainan, Guangxi, Shandong, etc.). These results suggested that NAD6 -D and NAD6 -I types may be useful in distinguishing between populations, analyzing the evolutionary mechanism of mtDNA microsatellite polymorphism, inferring the migratory route of S. frugiperda in China, and developing precise and integrated control strategies for S. frugiperda. [ABSTRACT FROM AUTHOR]

Automatic identification and location of farmland pests are an important direction of target detection research. The wide variety of pests and the similarity between pest categories make the automatic identification of farmland pests have some problems, such as high error rate and difficult identification. In order to achieve a better target for automatic identification and location of farmland pests, this paper proposes a lightweight pest detection model, and the network is the EfficientNet proposed by Google, which achieves the detection of 26 pests, the idea based on the classical Yolo target detection algorithm. First of all, features were extracted through the lightweight backbone, and then multiscale feature fusion is performed by PANet; finally, three feature matrices with different sizes were output to predict pests of different sizes. Using CIOU as the loss function of regression prediction better reflects the relative position of the prior box and the real box. The experimental results are compared with other lightweight algorithms, and the results show that the accuracy rate of the algorithm for identification and localization of agricultural pest in this paper is the highest and could reach 93.73%. Moreover, the model is lightweight and can be deployed on low-cost equipment, which reduces the cost of equipment and accurately predicts the status of pests and diseases in farmland. In practice, it is shown that the algorithm can effectively solve the problems of large number of pests, pest accumulation, background interference, and has strong robustness. [ABSTRACT FROM AUTHOR]

Novel core-shell structured CoNi2S4@polydopamine nanocomposites have been successfully developed as advanced electrode materials for supercapacitors. The CoNi2S4 nanoparticles are tightly wrapped by polydopamine, forming a hierarchical core/shell network, which benefits the improvement of the electrochemical properties. The electrochemical performance of the as-prepared materials had been investigated by cyclic voltammetry and galvanostatic charge/discharge tests. Specific capacitances of CoNi2S4 and CoNi2S4@polydopamine are 425 and 725 F g−1 at 10 A g−1 respectively. Electrochemical impedance spectroscopy results suggest that the coating of polydopamine can reduce the charge transfer resistance and increase the diffusion rate of the electrolytic ion efficiently. The superior pseudocapacitive performance of CoNi2S4@polydopamine can be ascribed to the unique core-shell heterostructure and the combined contribution of the electrochemical active CoNi2S4 and the conductive polydopamine. [ABSTRACT FROM AUTHOR]