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Linear cultural heritage—a heritage system spanning time and space—is a large-scale cultural settlement that accommodates various heritage types. Here, we comprehensively explored the Straight Road (Zhidao) of the Qin Dynasty in Shaanxi Province, China, as a gene of traditional cultural connotations and geographical features, and provided holistic conservation strategies and effective utilization paths. From an ecological security pattern perspective, 4399.89 km2 of ecological sources and 19 ecological nodes were identified based on the importance of four ecosystem services—carbon sequestration and oxygen release, water conservation, habitat maintenance, and soil retention. Then, 45 ecological corridors with a total length of 2938.49 km were determined using the minimum cumulative resistance model. The intersections of ecological corridors were distinguished and the key areas of cultural landscape construction were extracted by taking into account the spatial distribution of existing relics as well as the spatial network relationship of prohibited-development areas and existing gray corridors (roads), blue corridors (rivers), and green ecological corridors (shade zones, green belts, recreational greenways). A plan was proposed to construct 98.45 km2 of new parks (country parks: 28.38 km2, forest parks: 70.07 km2) and 101.26 km of new landscape corridors (urban type: 32.08 km, countryside type: 26.49 km, ecological type: 42.69 km). Multilevel landscape complexes should be built to form a functional and networked ecological–cultural spatial structure system. Findings of this study could provide ecological ideas for promoting the reservation and active utilization of linear cultural-heritage corridors on a regional scale. [ABSTRACT FROM AUTHOR]

The optimal allocation of educational resources has been a hot issue, and exploring the accessibility of educational facilities in poor mountainous areas helps to reasonably plan the layout of educational facilities and promote the balanced development of education. Taking the rocky desertification area in Yunnan, Guangxi, and Guizhou (YGGRD) as the study area, based on the POI data of educational facilities in the YGGRD in 2000, 2010 and 2019, this study explored the evolution of the accessibility of educational facilities in the YGGRD through raster accessibility. And the influencing factors were analyzed by the ordinary least square method (OLS) and geographically weighted regression model (GWR), and evaluated the model through cross validation. The results show that the overall accessibility of educational facilities improved significantly from 2000 to 2019. Educational facilities mainly have good accessibility and average accessibility. Poor accessibility areas are concentrated in the interprovincial border regions, and the boundary effect is significant. County accessibility, population density and rural per capita disposable income have a great impact on the accessibility of educational facilities in the YGGRD. It is suggested to strengthen the construction of educational facilities in the interprovincial border regions, relocate and integrate villages, and improve the education quality of township schools to improve the supply of rural educational resources. [ABSTRACT FROM AUTHOR]

Aiming at the particularity of a multiple-stage closed-loop gear transmission system for 3D circular braiding machine, the model of gear transmission system in radial braiding machine was simplified. The non-linear dynamic equations of a n-elements closed-loop gear transmission system with symmetrical structure including static transmission error, the random disturbance of meshing damping and backlash were considered. For convenience of calculation n = 3, the equations were solved numerically by using Runge-Kutta. The dynamic transmission error(DTE) with different backlash, dynamic meshing forces with and without the random disturbance of meshing damping, the amplitude of dynamic transmission error at n = 1000 r/min and b = 2.65 × 10−5 m, root mean square(RMS) of DTE and the mean value of DTE of the first pair of gears were analyzed. The simulation results show that different backlash and the random disturbance of meshing damping have a great influence on the dynamic displacement error and meshing force of the gear pair, and RMS and the mean value of DTE changes at different rotational speeds. The results will provide a reference for realizing the smoothness of the closed-loop gear transmission system with symmetrical structure for 3D braiding machine and have great practical significance for improving the braiding quality. [ABSTRACT FROM AUTHOR]

Chinese herbs are a useful resource bank for natural drug development, and have attracted considerable attention to exploit quorum sensing inhibitors (QSIs). This study was designed to screen QSIs from raw Chinese herb materials. Of the 38 common herbs examined, the ethanol extract of Campsis grandiflora flower had the strongest QSI activity. The C. grandiflora flower ethanol extract (CFEE) was purified by HPD600, and the QSI activities were examined in further detail. CFEE inhibited violacein production of Chromobacterium violaceum 026 in a dose-dependent manner, and inhibit the swarming abilities of Escherichia coli K-12 and Pseudomonas aeruginosa PAO1. Furthermore, CFEE could inhibited biofilm formation and destroyed mature biofilms of E. coli K-12 and P. aeruginosa PAO1. The composition of CFEE was determined by UPLC-MS/MS to distinguish active QSI compounds, and 21 compounds were identified. In addition to gallic acid and caffeic acid, two organic acids, malic acid and succinic acid, were confirmed for the first time to have autoinducer type 1 QSI activities. Therefore, CFEE is a potential QSI that could be used as a novel antimicrobial agent and should be considered for medicinal development. [ABSTRACT FROM AUTHOR]