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【Objective】 Cadmium is a heavy metal commonly seen in contaminated soils. Its uptake and translocation in plants depends on many factors. In this paper, we investigated the effect of soil Cd content on Cd uptake and its subsequent translocation and accumulation in two maize varieties. 【Method】 The experiment was conducted in a field, with Zhengdan 985 (ZD) and Xiangyu 335 (XY) varieties used as the model plants. Cd content in the soil varied from 0.16 mg/kg (CK) to 15.76 mg/kg. In each treatment, we measured the enrichment and translocation of Cd to each tissue organ and analyzed the correlation between soil Cd content and Cd content in different tissues and organs of the two varieties. 【Result】 In all treatments, Cd was mainly accumulated in the roots, leaves and bracts, followed by stalk and ear axis. Cd content in the seeds was 0.08%~5.12%, the lowest compared with that in other organs. Cd content in the seeds of ZD increased with the increase in soil Cd content, while the maximum Cd content in the seeds of XY was 0.26 mg/kg when the soil Cd content was 6.71 mg/kg. Analysis showed that the strongest enriching organ of ZD and XY was roots and the weakest was seeds. The enrichment of Cd in stems, leaves and bracts varied with soil Cd content, though there was a varietal difference. When soil Cd content was the same, the translocation of Cd in root-to-leaf and root-to-bud was the strongest, though there were a varietal difference and soil Cd effect. Cd content in the roots, stem, leaves, bract, rachis and seeds were significantly correlated with soil Cd content, with the correlation coefficient for the root, stem and leaf being 0.973, 0.961 and 0.963, respectively. 【Conclusion】 Distribution, enrichment and translocation of Cd in maize were affected by soil Cd content and the maize variety. Both ZD and XY grew healthily; there was only a limited Cd accumulation in their seeds when soil Cd content was 1.70~15.76 mg/kg, though the XY was more productive when soil Cd content was 1.70~6.71 mg/kg.

This paper proposes an improved YOLOv5 model based on the EfficientNet‐B0 backbone, EIoU loss function, and dynamic convolution operator, which was evaluated using the NEU‐DET dataset. The results show that compared with the traditional YOLOv5 model, the proposed improvement achieves a higher detection accuracy with fewer model parameters, resulting in a more lightweight architecture. Using the EfficientNet‐B0 backbone not only enhances the detection performance but also reduces the parameter count of the model, thereby, effectively improving computational efficiency. The enhanced EIoU loss function provided a more accurate assessment of the quality of the detected bounding boxes than the traditional CIoU loss function. Additionally, the dynamic convolution operator utilized in the neck module enhances the representation capability of the feature map while reducing computational overhead. The simulation results demonstrate that the proposed improved model achieves higher mean average precision (mAP) values and requires fewer parameters for the NEU‐DET dataset, thereby, highlighting its promising practical applications. [ABSTRACT FROM AUTHOR]

Introduction: The oxygen reduction reaction (ORR) is a crucial determinant of the energy transformation capacity of fuel cells. This study investigates the performance of N and B dual-doped carbon in ORR. Methods: Six models using density functional theory (DFT) are developed to compare the performance of different doping strategies. A highly efficient dual-doped carbon ORR catalyst (S-850-1) is synthesized from Saccharina japonica , containing 4.54 at% N and 1.05 at% B atom. Results: Electrochemical analysis reveals that S-850-1 significantly outperforms the nitrogen mono-doped carbon S-850, exhibiting a higher half-wave potential of 0.861 V and a greater limited current density of −5.60 mA cm⁻2, compared to S-850's 0.838 V and −5.24 mA cm⁻2. Furthermore, S-850-1 surpasses the performance of 20% Pt/C, demonstrating enhanced durability and exceptional resistance to CO and methanol. The 1.40 V open circuit voltage produced by S-850-1 when integrated into a Zn-air battery can power an LED light. Discussion: Both theoretical and practical evaluations validate the excellent ORR performance of nitrogen and boron dual-doped carbon, as evidenced by the agreement between the electrochemical results and DFT calculations. This work not only extends the range of ORR catalysts derived from biomass but also provides guidance on creating and producing affordable, effective catalysts that utilize natural resources. [ABSTRACT FROM AUTHOR]