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Exploring the response of spatial and temporal characteristics of ecological quality change to aridity on the Qinghai–Tibet Plateau (QTP) can provide valuable information for regional ecological protection, water resource management, and climate change adaptation. In this study, we constructed the Remote Sensing Ecological Index (RSEI) and Standardized Precipitation Evapotranspiration Index (SPEI) based on the Google Earth Engine (GEE) platform with regional characteristics and completely analyzed the spatial and temporal variations of aridity and ecological quality on the QTP in the years 2000, 2005, 2010, 2015, and 2020. Additionally, we explored the responses of ecological quality to aridity indices at six different time scales. The Mann–Kendall test, correlation analysis, and significance test were used to study the spatial and temporal distribution characteristics of meteorological aridity at different time scales on the QTP and their impacts on the quality of the ecological environment. The results show that the ecological environmental quality of the QTP has a clear spatial distribution pattern. The ecological environment quality is significantly better in the south-east, while the Qaidam Basin and the west have lower ecological environment quality indices, but the overall trend of environmental quality is getting better. The Aridity Index of the QTP shows a differentiated spatial and temporal distribution pattern, with higher Aridity Indexes in the north-eastern and south-western parts of the plateau and lower Aridity Indexes in the central part of the plateau at shorter time scales. Monthly, seasonal, and annual-scale SPEI values showed an increasing trend. There is a correlation between aridity conditions and ecological quality on the QTP. The areas with significant positive correlation between the RSEI and SPEI in the study area were mainly concentrated in the south-eastern, south-western, and northern parts of the QTP, where the ecological quality of the environment is more seriously affected by meteorological aridity.

Parental involvement may influence the subjective well-being of primary school students, but the specific mechanisms remain unclear. This study explores the mechanisms between parental involvement and primary school students’ subjective well-being. The current study investigated 340 fifth and sixth grade students and their parents from a primary school using the Parental Education Involvement Behavior Scale, the Well-Being Scale, the Sense of Security Scale, and the Learning Self-Regulation Scale. We found that (1) sense of security plays a complete mediating role between parental involvement and primary school students’ subjective well-being; (2) autonomous motivation has a marginal mediating effect between parental involvement and subjective well-being of primary school students; and (3) sense of security and autonomous motivation play a chain mediating role between parents’ educational involvement and primary school students’ well-being. In conclusion, parental involvement appears to contribute to primary school children’s subjective well-being, and this effect may be mediated individually and sequentially by the children’s sense of security and autonomous motivation.

For Si/C anodes, achieving excellent performance with a simple fabrication process is still an ongoing challenge. Herein, we report a green, facile and scalable approach for the in situ synthesis of Si@C anodes during the electrode manufacturing process by partially carbonizing Si nanoparticles (Si NPs) and dual polymers at a relatively low temperature. Due to the proper mass ratio of the two polymer precursors and proper carbonization temperature, the resultant Si-based anode demonstrates a typical Si@C core–shell structure and has strong mechanical properties with the aid of dual-interfacial bonding between the Si NPs core and carbon shell layer, as well as between the C matrix and the underlying Cu foil. Consequently, the resultant Si@C anode shows a high specific capacity (3458.1 mAh g−1 at 0.2 A g−1), good rate capability (1039 mAh g−1 at 4 A g−1) and excellent cyclability (77.94% of capacity retention at a high current density of 1 A g−1 after 200 cycles). More importantly, the synthesis of the Si@C anode is integrated in situ into the electrode manufacturing process and, thus, significantly decreases the cost of the lithium-ion battery but without sacrificing the electrochemical performance of the Si@C anode. Our results provide a new strategy for designing next-generation, high-capacity and cost-effective batteries.

Raman spectroscopy is widely used for qualitative and quantitative analysis of trace components in scientific fields such as food safety monitoring, drug testing, environmental monitoring, etc. In addition to its demonstrated advantages of fast response, non-destructive, and non-polluting characteristics, fast online Raman detection is drawing growing attention for development. To achieve this desirable capability, hollow core optical fibers are employed as a common transmission channel for light and fluid in the Raman sensor. By enhancing the interaction process between light and matter, the detection sensitivity is improved. At the same time, the Raman spectroscopy signal light collection efficiency is significantly improved. This article summarizes enhancement techniques reported for Raman sensors, followed by a detailed review on fiber-based Raman sensor techniques including theoretical analyses, fabrication, and application based on hollow core photonic crystal fibers and capillary-based hollow core fibers. The prospects of using these fibers for Raman spectroscopy are discussed.