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Nighttime semantic segmentation is an important but challenging research problem for autonomous driving. The major challenges lie in the small objects or regions from the under-/over-exposed areas or suffer from motion blur caused by the camera deployed on moving vehicles. To resolve this, we propose a novel hard-class-aware module that bridges the main network for full-class segmentation and the hard-class network for segmenting aforementioned hard-class objects. In specific, it exploits the shared focus of hard-class objects from the dual-stream network, enabling the contextual information flow to guide the model to concentrate on the pixels that are hard to classify. In the end, the estimated hard-class segmentation results will be utilized to infer the final results via an adaptive probabilistic fusion refinement scheme. Moreover, to overcome over-smoothing and noise caused by extreme exposures, our model is modulated by a carefully crafted pretext task of constructing an exposure-aware semantic gradient map, which guides the model to faithfully perceive the structural and semantic information of hard-class objects while mitigating the negative impact of noises and uneven exposures. In experiments, we demonstrate that our unique network design leads to superior segmentation performance over existing methods, featuring the strong ability of perceiving hard-class objects under adverse conditions. [ABSTRACT FROM AUTHOR]

High-density cities are growing in number and importance due to globalisation, significantly contributing to local, regional, and worldwide economies. It is progressively becoming clear that the high-density features of cities are associated with the frequency of disasters. As more than half of the world's population currently resides in cities, the study of high-density cities is evolving into an academic topic. In this study, the WoSCC (Web of Science Core Collection) and CiteSpace software were used to visualise and analyse the development history, current status, hotspots, and trends in high-density city research. We analysed a total of 377 valid articles spanning 2001 to 2022. This research aimed to illustrate the trajectory of high-density city development and to summarise the field's research hotspots and development history after entering the 21st century. It is hoped that this study will provide a theoretical reference and development direction for the future development of the field of high-density city research. Our results indicate that more publications have used the relevant keywords over time and that the research has overall trended from general to specific, noticeably changing in response to urban modernisation. Academic study in this area is still in its early stage. Instead of an inherent urge to spontaneously advance due to academic output, the research field has primarily grown in response to urban problems. COVID-19 has also hastened urban infill, further impacting existing high-density communities' urban environments, transportation infrastructure, and economies. The global epidemic has added urgency to research on high-density cities, and new content and directions are being developed. Assessing the hazards of high urban density while maximising its economic role is a significant part of academic research on high-density cities at this stage and will remain so in the future. [ABSTRACT FROM AUTHOR]

Along with the increase in modern industry, original facilities and cultures have disappeared progressively, leading to the disappearance of traditional values. However, from the perspective of the stewardship of industrial heritage, preservation is vital for Western Europe, where the Industrial Revolution emerged firstly, and it has leading technology in terms of the advanced stewardship of industrial heritage protection. Meanwhile, there is a large market for industrial heritage growth in China, but its stewardship began later. Horizontal and vertical research into the stewardship of the industrial heritage of these two regions offers a review of the developed industrial regions and experiences for developing industrial regions in their future expansion. By analysing the values and dilemmas and the features of the legal, administrative, and fund guarantee systems, this paper summarizes the advanced expertise of the stewardship of industrial heritage in Western Europe and China and proposes strategies based on them. [ABSTRACT FROM AUTHOR]

Next-generation wireless communication requires antennas with excellent performance and low-profile structures. A low-profile broadband dual-polarized base station antenna array with an artificial magnetic conductor (AMC) reflector and cross-polarization suppression structures is proposed. Cross-polarization is effectively suppressed by introducing the structures among the antenna elements with almost no impact on the other antenna performances, and the cross-polarization suppression mechanism is analyzed theoretically. The AMC reflector reduces the antenna profile only $0.12\lambda _{0}$ ($\lambda _{0}$ is the free-space wavelength at 4 GHz). Prototypes of the antenna element and the five-element antenna array are fabricated, and the simulated and measured results indicate that both achieve good performance over the entire operating frequency band. The antenna array has high isolation (>28 dB), a wide operating bandwidth (3.14–5.32 GHz, 51.5%), and stable radiation performances (XPD >29 dB, gain >15 dBi, FBR >37 dB). The proposed antenna array with good performance and a low profile may be a candidate for 5G communication applications. [ABSTRACT FROM AUTHOR]

This article presents a broadband dual-polarized dipole antenna for LTE/5G base station, which consists of loop dipoles, T-shaped cross-feeding lines, L-shaped parasitic elements, and metallic cylinders. As a result, the test results show good achievement of wide band (48.6%, 2.21–3.63 GHz), stable gain (8.3 dBi) and high port-to-port isolation (>30 dB). In addition, good cross-polarization discrimination (XPD) (>30 dB) and stable radiation pattern ( 65.5 ∘ ± 5.5 ∘ ) on horizontal plane are realized over the band by employing a rectangular box-shaped reflector. Furthermore, with simple structure, this antenna can provide partial reference for the design of LTE/5G base station antennas. [ABSTRACT FROM AUTHOR]

Angelica muliensis (Apiaceae), a new species from Sichuan Province, southwest China, is described and illustrated. The new species resembles A. biserrata, but differs in the shapes of the leaflets and sheaths, umbel number and size and especially mericarp features. The diagnostic characters of these two species are presented and compared. [ABSTRACT FROM AUTHOR]

Ostericum palustre is a critically Endangered species endemic to Europe and was described as the type-species of the genus Ostericum (Apiaceae). The complete chloroplast genome of O. palustre was reported for the first time, which suggested a circle quadripartite structure of 154923 bp in length comprising the large single-copy region (LSC) of 84750 bp, the small single-copy region (SSC) of 19752 bp, and a pair of inverted regions (IRs) of 25209 bp. There were totally 127 genes including 4 rRNAs, 37 tRNAs, and 82 protein-coding genes. In the phylogenetic analyses, O. palustre was very close to Pterygopleurum neurophyllum but distant from Angelica species, which coincided with the result of ITS sequences analysis. This study provided a significant genetic resource and will be helpful to systematic research and effective conservation. [ABSTRACT FROM AUTHOR]

Angelica sylvestris L. is the type species of the genus Angelica L., which was considered as one of the largest and most complicated groups in the family Apiaceae. The complete chloroplast genome of A. sylvestris was determined for the first time, and revealed a circle quadripartite structure of 146,910 bp in length comprising a large single-copy region (LSC) of 93,503 bp, a small single-copy region (SSC) of 17,833 bp and a pair of inverted regions (IRs) of 17,787 bp each. Based on the reported chloroplast genomes of Apioideae, phylogenetic analyses suggested that A. sylvestris was located in the Angelica group together with most Angelica species, which coincided with previous molecular systematic research. [ABSTRACT FROM AUTHOR]

A broadband dual-polarized base station antenna is proposed in this paper. The antenna consists of loop cross-dipoles, Y-shaped coupling feeding lines, and a metal box reflector. An equivalent circuit model including a signal flow diagram is established to analyze the mechanism of the proposed antenna in detail. Moreover, the Y-shaped coupling feeding lines are introduced to control the coupling with the antenna to achieve broadband and good impedance matching. The prototype of the antenna is fabricated and measured. The measured results show that the antenna with simple structures can operate at the band of 3.2–5.22 GHz (48%) with high port-to-port isolation (35 dB) and stable gain (9 ± 1 dBi). The measured results show good agreement with simulated results, especially in cross-polarization discrimination ratio (>27 dB) and the half power beam width (61° ± 3° at the E-plane, 68° ± 3° at the H-plane). In summary, the proposed antenna could be a good candidate for 5G sub-6 GHz base station applications. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Nitrogen‐containing polymers have found a wide myriad of applications in materials science and other different areas, and have attracted much attention towards the development of new synthetic methods. Ring‐opening metathesis polymerization represents an area of great versatility and potential for the synthesis of highly functionalized polymers with low dispersity and control over molecular weight and architecture complexity. Expanding the scope of monomers through the incorporation of nitrogen atoms would further expand their utilities. In this work, a controlled synthesis of polymers with in‐chain enamide moiety through ring‐opening metathesis polymerization was developed by utilizing azetine derivatives as the monomers. Relatively short synthetic routes were designed and generated a panel of five monomers. The polymerization exhibited living characteristics, as linear relationship between molecular weights and degrees of polymerization and relatively narrow molar mass distributions were observed, which was further confirmed by successful diblock copolymers formation through sequential addition of two monomers. The resulting polymers that contain the enamide moiety within the backbone exhibited good stability and underwent facile degradation under acidic conditions. [ABSTRACT FROM AUTHOR]

• A sandwich structure of C@Si@G is put out. • Every C@Si fiber is wrapped by single layer G (graphene) to constrain the volume expansion of Si (silicon). • Natural cocoon silk is applied as carbon-sourced substrate. • The as-prepared flexible C@Si@G composite is directly used as Li-ion anode without Copper foil (current collector). • The C@Si@G anode possesses an excellent discharge capacity of 1070 mAh g−1 at 0.2 A g−1 after 300 cycles. The commercial application of silicon is still impeded by poor conductivity and significant volume change. In this work, a C@Si@G composite was synthesized by a facile chemical solution reaction and carbonization procedure with cocoon silk as a natural carbon source. This composite has a sandwich structure, where Si nanoparticles as a sandwich middle layer and graphene (G) as an out layer. And it possesses the advantages of flexible, nitrogen-doped and is environmentally friendly. The optimized C@Si@G-15 composite is used as a self-supporting anode without a current collector, and it shows a reversible discharge capacity of 972 mAh g−1after 120 cycles at 1 A g−1 and a relatively high capacity of 1070 mAh g−1 after 300 cycles at 200 mA g−1, demonstrating the effect of coating the N-doped carbonized silk and the graphene synergistically to improve electrical connectivity and to constrain the pulverization of Si nanoparticles. Hence, it delivers great potential for application on wearable devices. [ABSTRACT FROM AUTHOR]

Ostericum citriodorum is a traditional Chinese medicinal herb endemic to Southeast and South China, but now is becoming very rare because of rapid habit loss. The complete chloroplast genome of O. citriodorum was sequenced herein and suggested that the complete chloroplast genome was 155,919 bp in length, comprising the large single-copy (LSC) region of 85,393 bp, the small single-copy (SSC) region of 19,760 bp, and a pair of inverted regions (IRs) of 25,383 bp. Totally 127 genes were distributed in the whole genome, including 4 rRNAs, 37 tRNAs, and 81 protein coding genes. The G + C content of this chloroplast genome was 38%. Phylogenetic inference revealed that O. citriodorum was accompanied with Pterygopleurum neurophyllum and sister to O. palustre , indicating a close relationship between Ostericum and Pterygopleurum ., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Angelica sylvestris L. is the type species of the genus Angelica L., which was considered as one of the largest and most complicated groups in the family Apiaceae. The complete chloroplast genome of A. sylvestris was determined for the first time, and revealed a circle quadripartite structure of 146,910 bp in length comprising a large single-copy region (LSC) of 93,503 bp, a small single-copy region (SSC) of 17,833 bp and a pair of inverted regions (IRs) of 17,787 bp each. Based on the reported chloroplast genomes of Apioideae, phylogenetic analyses suggested that A. sylvestris was located in the Angelica group together with most Angelica species, which coincided with previous molecular systematic research., Competing Interests: No potential conflict of interest was reported by the authors., (© 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)