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The capacity to extract information and comprehend an unseen environment is critical for mobile robots to navigate. Few surveys has mentioned the combinatorial-non-optimality problem of the traditional visual navigation methods. As computer vision technology has improved in recent years, visual navigation approaches have escalated drastically, particularly after the appearance of the CVPR Embodied AI workshop. However, few studies take these important changes into account. This survey fills this research gap by collecting, analyzing, and summarizing more than 100 recent papers. The majority of them are published within 5 years and are cited over 80 times, which provide more credible results. Based on our thorough comparison, this survey categorizes all visual navigation methods into two styles: geometry style and embodied AI style. This survey examines these two styles from the perspective of input–output. In addition, this survey attempts to provide mathematical formulations for each style. This paper provides a case study to illustrate the methodological paradigm with greatest potential. This methodological paradigm using photo-realistic simulation in the Embodied AI style, which could solve the combinatorial-non-optimality problem. Thereafter, this survey discusses several issues including pros–cons analysis, problem formulation, common framework, task generalization, dynamic environment consideration, sim-to-real, and inspiring approaches, which are all based on the scholars who have cited the method. In the last part, challenges and future trends are summarized. This survey would assist researchers who work on AI-empowered visual navigation systems. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is essential for the physiological processes of plants. However, the specific mechanisms by which different nitrogen forms influence rice blast pathogenesis remain poorly understood. This study used hydroponic assays to explore how ammonium (NH 4 +) and nitrate (NO 3 −) affect rice after inoculation with Magnaporthe oryzae (M. oryzae). The results showed that NH 4 +, compared to NO 3 −, significantly reduced disease severity, fungal growth, fungal hyphae number, the expansion capacity of infectious hyphae, and disease-related loss of photosynthesis. Additionally, NH 4 + enhanced the expression of defense-related genes, including OsPBZ1 , OsCHT1 , OsPR1a , and OsPR10. NH 4 +-treated rice also exhibited higher hydrogen peroxide (H 2 O 2) accumulation and increased antioxidant enzyme activities. Moreover, susceptibility to rice blast disease increased when H 2 O 2 was scavenged, while a reduction in susceptibility was observed with the application of exogenous H 2 O 2. These results suggest that ammonium enhances rice resistance to M. oryzae , potentially through H 2 O 2 accumulation. The findings provide valuable insights into how different nitrogen forms affect plant immunity in rice, which is crucial for controlling rice blast and ensuring stable food production. • How nitrogen forms affect rice blast disease and its underlying mechanism. • Compared with NO 3 − treatment, NH 4 + treatment significantly suppresses the rice blast severity. • Ammonium enhances rice resistance against M. oryzae through associated H 2 O 2 accumulation. [ABSTRACT FROM AUTHOR]

• Fabricate microlens arrays by embedding microspheres into PDMS films. • By scanning and stitching the images, achieve imaging over a large field. • FDTD simulations are used to characterize the cross talk between microspheres. The development of optical microscopy has greatly promoted the progress of biological fields, providing outstanding observation tools for genetics, molecular biology, and bioengineering technology, from the macro- to the micro-scale. Owing to the optical diffraction limit, the imaging resolution of traditional optical microscopy is limited. Recently, the use of microspheres has been demonstrated to aid the capability to realize super-resolution imaging under white light illumination; however, using this approach, the imaging field of view is only a few microns, due to the size of the microspheres. In this paper, we fabricated microlens arrays by embedding microspheres into polydimethylsiloxane (PDMS) films. Using this method, we have successfully achieved parallel imaging under the sub-diffraction-limited resolution using multiple microspheres with a magnification up to ×2.59–×2.99, and the observed results are consistent with finite-difference time-domain (FDTD) simulation results. Furthermore, two imaging modes were developed: the microlens array-based dynamic scanning imaging mode and the stochastic microlens array region imaging overlay reconstruction mode, a surface image of 900 μm2 was presented stitched with 210 images. This study combines the advantages of parallel imaging and dynamic imaging to increase efficiency and observation range. [ABSTRACT FROM AUTHOR]

Abstract Adopting a macroscopic perspective, this study employs intercity cooperation network analysis to assess the institutional performance of the Pearl River Delta's (PRD) integration policy. To assess whether the existing PRD intercity cooperation network is advancing the three objectives of the PRD integration policy in terms of cooperation patterns, actors' involvement, and cooperation fields, this study analyzed news published on the Internet and official government websites. The study concludes that: (1) the Shenzhen-Dongguan-Huizhou sub-region (SDH) and the Zhuhai-Zhongshan-Jiangmen sub-region (ZZJ) are entirely integrated as institutional entities, while Zhaoqing and Yunfu have not been integrated into the Guangzhou-Foshan-Zhaoqing sub-region (GFZ); (2) the PRD integration process remains a government-led administrative process, with market and civil society actors having had little influence on the governance structure; and (3) the primary areas of cooperation involve institutional design and economic development, and secondary functions, such as entertainment, education, and environmental protection, have not been fully undertaken. We also consider that the PRD's institutional spatial structure is a monocentric structure centered on Shenzhen, which is inconsistent with previous studies indicating a functional spatial structure known as a “Polynuclear Urban Region.” Highlights • The institutional spatial structure of Pearl River Delta is monocentric. • Three sub-regions of Pearl River Delta are not fully achieved. • Pearl River Delta integration process is a government-led administrative process. • The primary cooperation fields of Pearl River Delta integration are institutional design and economic development. [ABSTRACT FROM AUTHOR]