Solid polymer electrolytes: Ion conduction mechanisms and enhancement strategies

Solid polymer electrolytes (SPEs) possess comprehensive advantages such as high flexibility, low interfacial resistance with the electrodes, excellent film-forming ability, and low price, however, their applications in solid-state batteries are mainly hindered by the insufficient ionic conductivity especially below the melting temperatures, etc. To improve the ion conduction capability and other properties, a variety of modification strategies have been exploited. In this review article, we scrutinize the structure characteristics and the ion transfer behaviors of the SPEs (and their composites) and then disclose the ion conduction mechanisms. The ion transport involves the ion hopping and the polymer segmental motion, and the improvement in the ionic conductivity is mainly attributed to the increase of the concentration and mobility of the charge carriers and the construction of fast-ion pathways. Furthermore, the recent advances on the modification strategies of the SPEs to enhance the ion conduction from copolymer structure design to lithium salt exploitation, additive engineering, and electrolyte micromorphology adjustion are summarized. This article intends to give a comprehensive, systemic, and profound understanding of the ion conduction and enhancement mechanisms of the SPEs for their viable applications in solid-state batteries with high safety and energy density

A Review of Advances in Groundwater Evapotranspiration Research

Groundwater evapotranspiration (ETg) is an important component of the hydrological cycle in water-scarce regions and is important for local ecosystems and agricultural irrigation management. However, accurate estimation of ETg is not easy due to uncertainties in climatic conditions, vegetation parameters, and the hydrological parameters of the unsaturated zone and aquifers. The current methods for calculating ETg mainly include the WTF method and the numerical groundwater model. The WTF method often requires data supplementation from the numerical unsaturated model to reduce uncertainty; in addition, it relies on point-monitoring data and cannot solve the spatial heterogeneity of ETg. The ETg calculation module of the numerical groundwater model is set up too simply and ignores the influence from the unsaturated zone and surface cover. Subsequent research breakthroughs should focus on the improvement of WTF calculation theory and the setting up of an aquifer water-table fluctuation monitoring network. The numerical groundwater model should couple the surface remote sensing data with the unsaturated zone model to improve the accuracy of ETg calculation

Identifying the Driving Impact Factors on Water Yield Service in Mountainous Areas of the Beijing-Tianjin-Hebei Region in China

Clarifying the interrelationship between climate and land use/land cover (LULC) changes on water yield in mountainous areas is very urgent due to the dramatic decrease in the water availability of mountainous areas. In this study, the InVEST model was used to calculate the water yield of the mountainous area in Beijing–Tianjin–Hebei region (BTH) from 1980 to 2020, and six scenarios were designed to identify the contribution rates of climate and LULC change on the water yield. The results showed that, in 1980–2020, the water yield in the mountainous area of BTH was the largest in 1990, at 377.95 mm and the smallest in 1980, at 150.49 mm. After 2000, the interannual water yield showed a slightly increasing trend, which was significantly lower than the water yield in 1990, the values ranging from 217.01 mm to 324.65 mm. During the study period, the spatial distribution of the water yield was similar over the years, with high values in the south-central Taihang Mountain (THM) and the northeastern Yanshan Mountain (YSM). The THM was the main water yield area of the mountainous area in BTH. The annual water yield of farmland was the highest, followed by forest land and grassland, while the proportion of volumetric water yield was the largest in forest land with an increasing trend from 1980 to 2020 and the grassland showed a decreasing trend, while that of farmland increased first from 1980 to 2000 and decreased from 2000 to 2020. Climate is the key factor controlling the water yield of the mountainous area in BTH from 1980–2000, 2000 to 2020, and 1980 to 2020. In the period of 2000–2020, the effect of LULC on the water yield is negative, while the effect is positive in 1980–2000 and 1980–2020. The contribution rate of climate to the water yield increases in the THM, Bashang region (BSR) and YSM from the period 1980–2000 to 2000–2020, while that of LULC in those three regions changes from a positive impact in 1980–2000 to a negative impact in 2000–2020, and the contribution rate is also greatly reduced. In the long term, land revegetation will gradually benefit the water yield in the mountainous areas of BTH, including the THM, BSR, and YSM. These results can provide an important scientific and technological reference for the ecological management and protection of water source sites, as well as the planning and utilization of water resources in mountainous areas of BTH

Study on the Evaluation and Assessment of Ecosystem Service Spatial Differentiation at Different Scales in Mountainous Areas around the Beijing–Tianjin–Hebei Region, China

Ecosystem services are closely related to human wellbeing—which refers to the basic material conditions required to maintain high standards of quality of life, of health, and of safety and security, as well as good social relationships, and freedom of choice and action—and have a high potential value. The adequate valuation of ecosystem service values (ESV) is now an urgent need for the implementation of policy measures such as ecosystem asset management, ecological compensation and paid use of ecosystem services. Based on the method of ecosystem value equivalent factor per unit area, in this paper we investigated the variability of total ESV spatial distribution and regional differences in the value of 11 ecosystem service types provided by ecosystems in the mountainous areas of the Beijing–Tianjin–Hebei (BTH) region at different spatial scales and discussed the relationship between ESV and land use land cover (LULC). The results show that the total ESVs in 2015 and 2020 in the mountainous areas of BTH region were 5671 × 108 CNY and 6381 × 108 CNY, respectively. The change trend of each ecosystem service value from 2015 to 2020 was dominated by an increase of water supply service, and the maintenance of soil and nutrient cycle services in the mountainous area of BTH and the Yanshan Mountain (YSM). The change patterns of the value of ecosystem service categories in the Taihang Moutain (THM) and Bashang region (BSR) are dominated by an increase in the value of maintained soil and water supply services and a decrease in the value of regulating services. The calculation of ESV can be made more accurate by considering climate and vegetation conditions at the region, ecosystem, county or township scales rather than at grid scale, as, for calculating the interannual variation of total ESV, the spatial scale variability is large. The assessment of ESVs is important from the point of view of planning the use of the environment, of spatial planning, and of nature conservation. The ecosystem service of woodland and water bodies are more prominent compared with other land-use types and construction land and bare land provide the lowest value of service. There is some similarity between the value changes of ecosystem service categories and the distribution of LULC types. This study strengthens the understanding of the spatial scales of different ESV in mountain areas, which is beneficial to ecosystem management policies

Identifying the Driving Impact Factors on Water Yield Service in Mountainous Areas of the Beijing-Tianjin-Hebei Region in China

Clarifying the interrelationship between climate and land use/land cover (LULC) changes on water yield in mountainous areas is very urgent due to the dramatic decrease in the water availability of mountainous areas. In this study, the InVEST model was used to calculate the water yield of the mountainous area in Beijing–Tianjin–Hebei region (BTH) from 1980 to 2020, and six scenarios were designed to identify the contribution rates of climate and LULC change on the water yield. The results showed that, in 1980–2020, the water yield in the mountainous area of BTH was the largest in 1990, at 377.95 mm and the smallest in 1980, at 150.49 mm. After 2000, the interannual water yield showed a slightly increasing trend, which was significantly lower than the water yield in 1990, the values ranging from 217.01 mm to 324.65 mm. During the study period, the spatial distribution of the water yield was similar over the years, with high values in the south-central Taihang Mountain (THM) and the northeastern Yanshan Mountain (YSM). The THM was the main water yield area of the mountainous area in BTH. The annual water yield of farmland was the highest, followed by forest land and grassland, while the proportion of volumetric water yield was the largest in forest land with an increasing trend from 1980 to 2020 and the grassland showed a decreasing trend, while that of farmland increased first from 1980 to 2000 and decreased from 2000 to 2020. Climate is the key factor controlling the water yield of the mountainous area in BTH from 1980–2000, 2000 to 2020, and 1980 to 2020. In the period of 2000–2020, the effect of LULC on the water yield is negative, while the effect is positive in 1980–2000 and 1980–2020. The contribution rate of climate to the water yield increases in the THM, Bashang region (BSR) and YSM from the period 1980–2000 to 2000–2020, while that of LULC in those three regions changes from a positive impact in 1980–2000 to a negative impact in 2000–2020, and the contribution rate is also greatly reduced. In the long term, land revegetation will gradually benefit the water yield in the mountainous areas of BTH, including the THM, BSR, and YSM. These results can provide an important scientific and technological reference for the ecological management and protection of water source sites, as well as the planning and utilization of water resources in mountainous areas of BTH

FGFR1OP tagSNP but Not CCR6 Polymorphisms Are Associated with Vogt-Koyanagi-Harada Syndrome in Chinese Han

BACKGROUND: Polymorphisms of the CC chemokine receptor 6 (CCR6) and FGFR10P tagSNP (locus close to CCR6) at 6q27 have recently been reported to be associated with the susceptibility to several immune-related diseases. This study was designed to determine the association of CCR6 and FGFR10P (tag)SNPs with Vogt-Koyanagi-Harada (VKH) syndrome, an autoimmune disease directed against melanocytes, in two independent Chinese Han populations. METHODOLOGY/PRINCIPAL FINDINGS: A total of 601 VKH patients and 725 healthy controls from two Chinese Han populations were genotyped by the polymerase chain reaction-restriction fragment length polymorphism method. Hardy-Weinberg equilibrium was tested using the χ(2) test. Genotype frequencies were estimated by direct counting. Allele and genotype frequencies were compared between patients and controls using the χ(2) test. The frequency of the A allele of rs2301436 was significantly higher both in Cohort 1 and Cohort 2 as compared with two separate controls (P = 0.044; P = 0.049, respectively). The significance was lost after Bonferroni correction in both cohorts (Pc = 0.516; Pc = 0.392, respectively). The frequency of the A allele was significantly higher in the combined patient group as compared with all controls before and after Bonferroni correction (P = 0.005, Pc = 0.025). The genotype and allele frequencies of rs3093024, rs6902119, rs3093023 and rs968334 were not different between patients with VKH and healthy controls based on analysis either for both cohorts or for the patients and controls in total. Analysis according to extra ocular clinical findings including headache, alopecia and poliosis, vitiligo and tinnitus did not show any association of the five polymorphisms with these parameters. CONCLUSION: These results suggest that the rs2301436 tagSNP of FGFR10P is positively associated with susceptibility to VKH syndrome in the tested Chinese Han populations. No association was found for the tested CCR6 SNPs

Effect of WeChat-based intervention on food safety knowledge, attitudes and practices among university students in Chongqing, China: a quasi-experimental study

Background: Food safety is of global importance and has been of concern in university settings in recent years. However, effective methods to conduct food safety education are limited. This study aims to evaluate the effects of an intervention on food safety knowledge, attitudes and practices (KAP) by social media, WeChat, among university students. Methods: A quasi-experimental study was conducted in Chongqing, China. Two departments were recruited randomly from a normal university and a medical university. One department from each university was randomly selected as the intervention group and the other as the control group. All freshmen students in each selected department were chosen to participate in this study. One thousand and twenty-three students were included at baseline, and 444 students completed the study. This intervention was conducted through food safety-related popular science articles with an average of three articles per week released by WeChat official accounts called "Yingyangren" for two months to the intervention group. No intervention was conducted in the control group. An independent t-test was used to test statistical differences in the food safety KAP scores between the two groups. A paired t-test was used to test statistical differences in the food safety KAP scores between before and after the intervention. And quantile regression analysis was conducted to explore the difference between the two groups across the quantile levels of KAP change. Results: After the intervention, compared with control group, participants in the intervention group did not score significant higher on knowledge (p = 0.98), attitude (p = 0.13), and practice (p = 0.21). And the scores of food safety knowledge and practices slightly improved after the intervention both in the intervention group (p = 0.01 and p = 0.01, respectively) and in the control group (p = 0.0003 and p = 0.0001, respectively). Additionally, the quantile regression analysis showed that the intervention had no effect on improving the food safety KAP scores. Conclusions: The intervention using the WeChat official account had limited effects on improving the food safety KAP among the university students. This study was an exploration of food safety intervention using the WeChat official account; valuable experience can be provided for social media intervention in future study. Trial registration: ChiCTR-OCH-14004861

Effect of WeChat-based intervention on food safety knowledge, attitudes and practices among university students in Chongqing, China: a quasi-experimental study

Abstract Background Food safety is of global importance and has been of concern in university settings in recent years. However, effective methods to conduct food safety education are limited. This study aims to evaluate the effects of an intervention on food safety knowledge, attitudes and practices (KAP) by social media, WeChat, among university students. Methods A quasi-experimental study was conducted in Chongqing, China. Two departments were recruited randomly from a normal university and a medical university. One department from each university was randomly selected as the intervention group and the other as the control group. All freshmen students in each selected department were chosen to participate in this study. One thousand and twenty-three students were included at baseline, and 444 students completed the study. This intervention was conducted through food safety-related popular science articles with an average of three articles per week released by WeChat official accounts called "Yingyangren" for two months to the intervention group. No intervention was conducted in the control group. An independent t-test was used to test statistical differences in the food safety KAP scores between the two groups. A paired t-test was used to test statistical differences in the food safety KAP scores between before and after the intervention. And quantile regression analysis was conducted to explore the difference between the two groups across the quantile levels of KAP change. Results After the intervention, compared with control group, participants in the intervention group did not score significant higher on knowledge (p = 0.98), attitude (p = 0.13), and practice (p = 0.21). And the scores of food safety knowledge and practices slightly improved after the intervention both in the intervention group (p = 0.01 and p = 0.01, respectively) and in the control group (p = 0.0003 and p = 0.0001, respectively). Additionally, the quantile regression analysis showed that the intervention had no effect on improving the food safety KAP scores. Conclusions The intervention using the WeChat official account had limited effects on improving the food safety KAP among the university students. This study was an exploration of food safety intervention using the WeChat official account; valuable experience can be provided for social media intervention in future study. Trial registration ChiCTR-OCH-14004861