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The combination of high-performance materials and simplified multilayer fabrication processes can promote the rapid and high-quality development of memristors. In this work, we proposed wide-bandgap semiconductor silicon carbide (SiC)-based memristors fabricated entirely by electron beam evaporation technology. The Cu/SiC/Pt structure was fabricated on a 2-inch intrinsic silicon substrate, which can achieve a transition from volatility to non-volatility. Devices had a low and symmetric switching voltage of ±0.5 V, an endurance of >200 cycles, a retention of >103 s, an ON/OFF ratio of ∼103, and can achieve at least 6 different stable resistance states. The combined effects of traps and Cu conductive filaments caused the current to change abruptly during switching, while also possessing excellent synaptic plasticity and pulse programming ability. Our work demonstrated that wide-bandgap semiconductor SiC is a promising candidate for advanced memristors. [ABSTRACT FROM AUTHOR]

The benchmarking of CO2 emissions serves as the foundation for the accurate assessment of the environmental impact of air traffic. To calculate the environmental benchmarks of arrival traffic flows with Point Merge System (PMS) patterns, this study proposes a 4D trajectory optimization method that combines data-driven and optimal control models. First, the predominant arrival routes of traffic flows are identified using the trajectory spectral clustering method, which provides the horizontal reference for 4D trajectory optimization. Second, an optimal control model for vertical profiles with point merging topology is established, with the objective of minimizing the fuel–time cost. Finally, considering the complex structure of the PMS, a flexible and adaptable genetic algorithm-based vertical profile nonlinear optimization model is created. The experimental results demonstrate that the proposed method is adaptable to variations in aircraft type and cost index parameters, enabling the generation of different 4D trajectories. The results also indicate an environmental efficiency gap of approximately 10% between the actual CO2 emissions of the arrival traffic flow example and the obtained benchmark. With this benchmark trajectory generation methodology, the environmental performance of PMSs and associated arrival aircraft scheduling designs can be assessed on the basis of reliable data. [ABSTRACT FROM AUTHOR]

The accuracy of registration in image stitching task directly affects the performance of subsequent stages. Traditional registration methods rely heavily on the quality of the features when calculating the homography matrix, resulting in alignment failures in low‐texture or low‐overlap scenes due to extracting insufficient features. On the other hand, existing DNN‐based methods for homography estimation are more robust in multiple scenes but previous work usually employs an overly simple convolutional network structure to directly regress the homography, ignoring the redundant information contained in the feature maps so that their prediction accuracy is inferior to the traditional methods in simple scenarios. To overcome the disadvantages of the two methods, a Multi‐scale structure is proposed to extract feature maps at three scales and design two modules to handle the matrix prediction respectively. The DFA‐T module analyzes semantic information on the high‐level features to accomplish coarse‐grained alignment while the Contextual Correlation module on the bottom level to accomplish more accurate alignment. Experiments demonstrate that this method provides more accurate alignment results than the existing state‐of‐the‐art DNN‐based methods and outperforms traditional algorithms with more stable results in some extreme scenarios. [ABSTRACT FROM AUTHOR]

SUMMARY: C4 plants partition photosynthesis enzymes between the bundle sheath (BS) and the mesophyll (M) cells for the better delivery of CO2 to RuBisCO and to reduce photorespiration. To better understand how C4 photosynthesis is regulated at the transcriptional level, we performed RNA‐seq, ATAC‐seq, ChIP‐seq and Bisulfite‐seq (BS‐seq) on BS and M cells isolated from maize leaves. By integrating differentially expressed genes with chromatin features, we found that chromatin accessibility coordinates with epigenetic features, especially H3K27me3 modification and CHH methylation, to regulate cell type‐preferentially enriched gene expression. Not only the chromatin‐accessible regions (ACRs) proximal to the genes (pACRs) but also the distal ACRs (dACRs) are determinants of cell type‐preferentially enriched expression. We further identified cell type‐preferentially enriched motifs, e.g. AAAG for BS cells and TGACC/T for M cells, and determined their corresponding transcription factors: DOFs and WRKYs. The complex interaction between cis and trans factors in the preferential expression of C4 genes was also observed. Interestingly, cell type‐preferentially enriched gene expression can be fine‐tuned by the coordination of multiple chromatin features. Such coordination may be critical in ensuring the cell type‐specific function of key C4 genes. Based on the observed cell type‐preferentially enriched expression pattern and coordinated chromatin features, we predicted a set of functionally unknown genes, e.g. Zm00001d042050 and Zm00001d040659, to be potential key C4 genes. Our findings provide deep insight into the architectures associated with C4 gene expression and could serve as a valuable resource to further identify the regulatory mechanisms present in C4 species. Significance Statement: C4 plants have better light‐use efficiency than C3 as they partition photosynthetic enzymes between the bundle sheath and the mesophyll cells to concentrate CO2 around RuBisCO. To understand the regulatory mechanisms behind this process, we investigated chromatin and regulatory differentiation between bundle sheath and mesophyll cells in maize leaves and found that chromatin accessibility coordinates with epigenetic features to fine‐tune cell type‐preferentially enriched gene expression. [ABSTRACT FROM AUTHOR]