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Several possible lithosphere–atmosphere–ionosphere coupling mechanisms before earthquake occurrence are presented in the literature. They are described by several models with different interaction channels (e.g., electromagnetic, mechanics, chemical, thermal), sometimes in conflict with each other. In this paper, we search for anomalies six months before the Lushan (China) 2013 earthquake in the three geo-layers looking for a possible view of the couplings and testing if one or another is more reliable to describe the observations. The Lushan earthquake occurred in China's Sichuan province on 20 April 2013, with a magnitude of Mw = 6.7. Despite the moderate magnitude of the event, it caused concern because its source was localized on the southwest side of the same fault that produced the catastrophic Wenchuan event in 2008. This paper applies a geophysical multi-layer approach to search for possible pre-earthquake anomalies in the lithosphere, atmosphere, and ionosphere. In detail, six main increases in the accumulated seismic stress were depicted. Anomalous geomagnetic pulsations were recorded in the Chengdu observatory, sometimes following the increased stress. Atmosphere status and composition were found to be anomalous in several periods before the earthquake, and, spatially, the anomalies seem to appear firstly far from the upcoming earthquakes and later approaching the Longmenshan fault where the Lushan earthquakes nucleated. The Formosat-3 data identified interesting anomalies in the altitude or electron content of the ionospheric F2 peak in correspondence with seismic and atmospheric anomalies 130 days before the earthquake. In addition, the total electron content showed high anomalous values from 12 to 6 days before the earthquake. We compared the anomalies and tried to explain their correspondences in different geo-layers by the lithosphere–atmosphere–ionosphere coupling models. In particular, we identified three possible couplings with different mechanisms: a first, about 130 days before the earthquake, with a fast (order of one day) propagation delay; a second, about 40 days before the earthquake occurrence, with a propagation delay of few days and a third from 2.5 weeks until one week before the event. Such evidence suggests that the geo-layers could interact with different channels (pure electromagnetic or a chain of physical-chemical processes) with specific propagation delays. Such results support the understanding of the preparation for medium and large earthquakes globally, which is necessary (although not sufficient) knowledge in order to mitigate their impact on human life. [ABSTRACT FROM AUTHOR]

In this study, the standard tent used by the China International Medical Team (Sichuan) was used as the research object to study the internal temperature change in medical tents in a low-temperature environment relying on heating equipment. Method: Four temperature sensors were arranged along the horizontal direction at a 1.2 m height in the medical tent, and more sensors were installed at heights of 0.1, 0.2, 0.6, 1.2, 1.8, 2.4, and 2.5 m. A total of 11 temperature sensors were set. Temperature tests were conducted in January and February 2021 in Chengdu, Sichuan Province. During the test, the running time of the heating equipment was controlled in real time according to the temperature change trend. A Kolmogorov–Smirnov(K-S) test was used to verify the reliability of the experimental data. The temperature change trend was used to characterize the influence of the heating and cooling equipment on the temperature change inside the tent. Results: Due to the position angle of the heating equipment and the influence of the external environment, the spatial distribution of the ambient temperature inside the medical tent was obviously uneven. In winter, an electric heater with a heating power of about 2500 W can increase the internal temperature of the tent to 16.7 °C, significantly improving the internal thermal environment of the medical tent. The ambient temperature in the medical tent is positively correlated with the height and the installation position of the heating equipment. Conclusion: Medical tents can maintain the ambient temperature well to meet medical needs with the support of heating equipment with sufficient power. The temperature distribution law of medical tents in this experiment has good guiding significance for the placement angle of heating equipment and the configuration position of medical equipment and provides a reference for the development of thermal insulation materials for medical tents. [ABSTRACT FROM AUTHOR]

To investigate and evaluate the spatial distribution of Zn, Pb and Cd in the soil around a municipal solid waste incineration plant and its ecological risks, Zn, Pb and Cd were analyzed in soil samples around a municipal solid waste incineration plant in Chengdu, Sichuan Province, China. The results revealed that the average content of Zn and Pb did not exceed the soil environmental quality value for the risk control standard for soil contamination of agricultural land (GB15618-2018), but the average content of Cd in the soil was higher than this standard. Multivariate statistical analysis indicated that Cd was the predominant pollutant and had strong correlations with Zn and Pb. The Cd content was most impacted by human activities, which also explained that this municipal solid waste incineration plant has little effect on Zn, Pb and Cd in the surrounding soil. The geo-accumulation index decreased in the order of Cd > Zn > Pb, and the geo-accumulation index of Cd was greater than 5, indicating that the pollution level for Cd was extremely heavy. The comprehensive potential ecological risk index (RI) of various heavy metals was greater than 1200, And the potential ecological risk level of the study area was high. The contribution rate of Cd to RI was relatively large, and Cd pollution should be paid more attention to. [ABSTRACT FROM AUTHOR]

(1) Background: Universities play a crucial role in nurturing healthy habits, and physical activity has emerged as a valuable tool for enhancing the life satisfaction, self-efficacy, and resilience of college students. Therefore, the purpose of this study was to investigate the mediating role of physical activity in the relationship between life satisfaction and self-efficacy as well as resilience among Chinese university students. (2) Method: This study used the Physical Activity Rating Scale (PARS-3), the Self-Efficacy Scale (CGES), the Mental Toughness Scale (CD-RISC), and the Life Satisfaction Scale (CSLSS) to administer questionnaires to 353 university students from two universities in Chengdu, Sichuan Province. Using a random simple sampling method, the data were processed and analyzed using SPSS 22.0 and Excel software. (3) Results: (1) Physical activity exhibited a significant positive correlation with self-efficacy, resilience, and life satisfaction; self-efficacy was significantly and positively related to resilience and life satisfaction; and resilience was significantly and positively related to life satisfaction. (2) Physical activity had a positive predictive effect on life satisfaction (β = 0.2771; 95% confidence interval (CI): 0.1905, 0.3637, 55.51%). (3) Self-efficacy (β = 0.0368; 95% confidence interval (CI): 0.0087, 0.0692, 7.37%) and resilience (β = 0.137; 95% confidence interval (CI): 0.0919, 0.1894, 27.44%) mediated the relationship between physical activity and life satisfaction. Also, the chain-mediating effect of self-efficacy and resilience between physical activity and life satisfaction reached significant levels (β = 0.0483; 95% confidence interval (CI): 0.0279, 0.0745, 9.68%). (4) Conclusion: Active participation in physical activity not only enhanced the life satisfaction of college students but also indirectly impacted their life satisfaction by improving their self-efficacy and resilience. Consequently, this led to an overall improvement in the life satisfaction of college students. [ABSTRACT FROM AUTHOR]

Kiwifruit brown spot caused by Corynespora cassiicola is the most significant fungal disease in Sichuan, resulting in premature defoliation, which had a significant impact on yield and fruit quality. The objective of the study was to determine the occurrence regularity and suitability of kiwifruit brown spot in Sichuan. The occurrence of the disease in the main producing region was continuously monitored, the maximum entropy (MaxEnt) model was used to predict its potential distribution, and the key environmental variables were identified using the jackknife method. The results indicated that kiwifruit brown spot was widely distributed across the entire producing region in Sichuan, predominantly affecting the variety "Hongyang". The incidence (p < 0.01) and disease index (p < 0.05) showed a significant positive correlation with the cultivar, and decreased with the altitude increasing. The average area under the ROC curve (AUC) of 10 replicates was 0.933 ± 0.012, with an accuracy of 84.44% in a field test, confirming the reliability of the predicted results. The highly suitable distribution areas of kiwifruit brown spot were mainly located in the Chengdu and Ya'an regions. The entire Panzhihua region was an unsuitable distribution area, and the entire Pujiang County and Mingshan District were highly suitable distribution areas. The key environmental variables affecting the potential distribution of kiwifruit brown spot included isothermality (24.3–33.7%), minimum temperature in August (16.3–23.6 °C), maximum temperature in July (25.5–31.2 °C), minimum temperature in June (15.6–20.9 °C), precipitation in August (158–430 mm), and average temperature in October (15.6–18.8 °C). This study provides a theoretical basis for the reasonable layout of the cultivar and the precise prevention and control of the disease. [ABSTRACT FROM AUTHOR]

The purpose of this study is to reveal the characteristics and driving factors of cropland change in Sichuan Province. This study summarizes the current status of coordination among croplands, ecosystem protection, and urban expansion in the region and provides suggestions for the rational use and conservation of arable land resources. The research methods include ArcGis spatial analysis and the PLUS model. The results show that: (1) The cropland area in Sichuan Province has been continuously decreasing over the past 21 years, but arable land protection policies have effectively mitigated this situation. (2) With the exception of Chengdu, the reduction of arable land in each city in Sichuan province has gradually balanced out, safeguarding the development of major and lagging cities. (3) "Dual suitability" refers to the conflict between urban development and planting. Moreover, due to the Matthew effect, urban development further promoted the expansion of construction lands, leaving croplands in a weak position in the competition with construction lands. (4) Sichuan Province showed the characteristics of alternating leadership between urbanization of land and population urbanization during the process of urban development occupying cropland. In conclusion, the decreasing trend of croplands in Sichuan Province has gradually improved, and the coordination between cropland, ecosystem, and urban space has been achieved. [ABSTRACT FROM AUTHOR]

As air quality has improved rapidly in recent years, the public has become more interested in whether a famous snow peak, Yaomei Feng on the Tibetan Plateau, can be seen from Chengdu, a megacity located on the western plain of the Sichuan Basin, east of the plateau. Therefore, a threshold-method-based forecasting system for snow peak sighting was developed in this study. Variables from numerical models, including cloud–water mixing ratio, cloud cover over snow peak, water mixing ratio, PM2.5 concentration, and ground solar radiation, were used in the snow peak sighting forecast system. Terrain occlusion rate of each model grid was calculated. Monte Carlo simulations were applied for threshold determination. A WRF-CMAQ hindcast was conducted for 2020, owing to insufficient observation data, hindcast results on the snow peak sighting were compared with posts collected from social media. Estimations showed that the snow peak sighting forecast system performed well in reflecting the monthly trend of snow peak sightings, and the hindcast results matched the daily observations, especially from May to August. Accuracy of the snow peak sighting forecast model was 78.9%, recall value was 57.1%, and precision was 24.4%. [ABSTRACT FROM AUTHOR]

Unlike a modern archaeological excavation of a Buddhist hoard, this article focuses on a collection of free-standing Buddhist images retrieved from at least four unofficial and intermittent excavations between 1882 and the 1950s. The excavation site in question is associated with the former site of Wanfosi, a historical monastery that has been destroyed and rebuilt multiple times from the early Tang to late Qing. By examining various sources, including antiquarian scholarships, local gazetteers, pre-modern maps, and important Buddhist images found within the hoard, I aim to provide essential information that pertains to modern archaeology. This article seeks to address issues such as the accurate identification of the excavation location, the provenance of all materials from a single Buddhist hoard, the historical lineage of the monastery from which insights are gathered into the image cache, and the noteworthy observation that the preservation of the pre-Tang images occurred long before the final burial. [ABSTRACT FROM AUTHOR]

This paper reports on a large-scale landslide with a movement of 48 thousand m3 of soil and rock that occurred in Sichuan, China. This catastrophic landslide occurred in Aidai village, Ganluo County, at 12:44 on 14 August 2019, blocking a section of the railway between Lianghong station and Aidai station. This landslide resulted in 12 deaths and five people missing. This report describes the preliminary investigation, the rescue activity, topographic survey and analysis as well as the main predisposing and triggering factors. The combined effects of steep topography, continuous rainstorms, floods eroding the foothills of the mountain and human activity were the main influencing factors that triggered this landslide. To reduce the possibility of casualties resulting from large geological disasters, such as landslides and mudslides, in this region in the future, some recommendations are proposed to systematically reduce potential human casualties and economic losses. [ABSTRACT FROM AUTHOR]

Painted stone carvings from Pujiang Museum in Chengdu were excavated from the Ming tombs near to Chengdu Metro Line 7. The Ming burial sites were the eunuch graves of the Shu King, and their tomb was constructed mostly of stone and decorated with paintings and carvings on its surface, which are of great value. However, during their burial, these painted stone carvings suffered significant salt damage. In this research, we performed optical microscope (OM) analysis, Raman spectra (RAM), ion chromatography (IC) analysis, X-ray fluorescence spectroscopy (XRF), X-ray powder diffraction (XRD), and petrographic microscopy (PM) to clarify the salt composition and influence. According to the results, the majority of the salt on the painted layer is CaSO4·2H2O. Before excavation, interaction between acid rain, soil, and groundwater created salt efflorescence on the paint layer's surface. The deterioration of the paint layer caused by gypsum was divided into two stages: before excavation and during in situ preservation. This research provides a foundation for the removal and prevention of salt efflorescence. [ABSTRACT FROM AUTHOR]

The widespread escalation of bacterial resistance threatens the safety of the food chain. To investigate the resistance characteristics of E. coli strains isolated from disinfected tableware against both disinfectants and antibiotics, 311 disinfected tableware samples, including 54 chopsticks, 32 dinner plates, 61 bowls, 11 cups, and three spoons were collected in Chengdu, Sichuan Province, China to screen for disinfectant- (benzalkonium chloride and cetylpyridinium chloride) and tigecycline-resistant isolates, which were then subjected to antimicrobial susceptibility testing and whole genome sequencing (WGS). The coliform-positive detection rate was 51.8% (161/311) and among 161 coliform-positive samples, eight E. coli strains were multidrug-resistant to benzalkonium chloride, cetylpyridinium chloride, ampicillin, and tigecycline. Notably, a recently described mobile colistin resistance gene mcr-10 present on the novel IncFIB-type plasmid of E. coli EC2641 screened was able to successfully transform the resistance. Global phylogenetic analysis revealed E. coli EC2641 clustered together with two clinically disinfectant- and colistin-multidrug-resistant E. coli strains from the US. This is the first report of mcr-10-bearing E. coli detected in disinfected tableware, suggesting that continuous monitoring of resistance genes in the catering industry is essential to understand and respond to the transmission of antibiotic resistance genes from the environment and food to humans and clinics. [ABSTRACT FROM AUTHOR]

Sichuan Basin is one of the most densely populated areas in China and the world. Human activities have great impact on the air quality. In order to understand the characteristics of overall air pollutants in Sichuan Basin in recent years, we analyzed the concentrations of six air pollutants monitored in 22 cities during the period from January 2015 to December 2020. During the study period, the annual average concentrations of CO, NO2, SO2, PM2.5 and PM10 all showed a clear downward trend, while the ozone concentration was slowly increasing. The spatial patterns of CO and SO2 were similar. High-concentration areas were mainly located in the western plateau of Sichuan Basin, while the concentrations of NO2 and particulate matter were more prominent in the urban agglomerations inside the basin. During the study period, changes of the monthly average concentrations for pollutants (except for O3) conformed to the U-shaped pattern, with the highest in winter and the lowest in summer. In the southern cities of the basin, secondary sources had a higher contribution to the generation of fine particulate matter, while in large cities inside the basin, such as Chengdu and Chongqing, air pollution had a strong correlation with automobile exhaust emissions. The heavy pollution incidents observed in the winter of 2017 were mainly caused by the surrounding plateau terrain with typical stagnant weather conditions. This finding was also supported by the backward trajectory analysis, which showed that the air masses arrived in Chengdu were mainly from the western plateau area of the basin. The results of this study will provide a basis for the government to take measures to improve the air quality in Sichuan Basin. [ABSTRACT FROM AUTHOR]

Earthquakes have catastrophic effects on the affected population, especially in undeveloped countries or regions. Minimizing the impact and consequences of earthquakes involves many decisions and disaster relief operations that should be optimized. A critical disaster management problem is to construct shelters with reasonable capacity in the right locations, allocate evacuees, and provide relief materials to them within a reasonable period. This study proposes a bi-objective hierarchical model with two stages, namely, the temporary shelter stage and the short-term shelter stage. The proposed objectives at different stages are to minimize the evacuation time, maximize the suitability based on qualitative factors, and minimize the number of sites while considering the demand, capacity, utilization, and budget constraints. The performance evaluation of the emergency shelter was carried out by fuzzy-VIKOR, and the most ideal location of the shelter was determined through multiple standards. Emergency management organizations can benefit from the collective expertise of multiple decision-makers because the proposed method uses their knowledge to automate the location and allocation process of shelters. In the case of Chengdu, Sichuan Province, China, the results of using this hybrid approach provide the government with a range of options. This method can realize the trade-off between efficiency and cost in the emergency shelter location and material distribution, and realize reliable solutions in disaster emergencies. [ABSTRACT FROM AUTHOR]

As a southwestern province of China, Sichuan is confronted with geographical disparities in access to healthcare professionals because of its complex terrain, uneven population distribution and huge economic gaps between regions. With 10-year data, this study aims to explore the county-level spatial disparities in access to different types of healthcare professionals (licensed doctors, registered nurses, pharmacists, technologists and interns) in Sichuan using temporal and spatial analysis methods. The time-series results showed that the quantity of all types of healthcare professionals increased, especially the registered nurses, while huge spatial disparities exist in the distribution of healthcare professionals in Sichuan. The local Moran's I calculations showed that high–high clusters (significantly high healthcare professional quantity in a group of counties) were detected in Chengdu (capital of Sichuan) and relatively rich areas, while low–low clusters (significantly low healthcare professional quantity in a group of counties) were usually found near the mountain areas, namely, Tsinling Mountains and Hengduan Mountains. The findings may deserve considerations in making region-oriented policies in educating and attracting more healthcare professionals to the disadvantaged areas. [ABSTRACT FROM AUTHOR]