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Liangshan Prefecture, located at the northeastern edge of the Hengduan Mountain System and within the southern section of the Sichuan-Yunnan tectonic belt in Sichuan Province, China, a region prone to landslides, collapses and debris flows due to its active tectonics, complex topography and significant river erosion. By analysing a dataset of environment factors and geological hazard catalogue, the research uses the Relief algorithm to identify critical influencing factors for each hazard type, selecting 10, 9 and 9 factors for landslides, collapses and debris flows, respectively. Five models are used to assess the vulnerability of these hazards: the Information Value model, the Evidence Weight model, the Logistic Regression model, and both the Evidence Weight-Logistic Regression and the Information Value-Logistic Regression coupled models. The effectiveness of these models is confirmed by confusion matrix and ROC curve analyses, with the combined models showing particularly high accuracy in assessing susceptibility. High risk zones were identified in specific areas and along major fault zones in Liangshan Prefecture. The research provides significant insights into the susceptibility of geological hazards in mountainous and canyon regions, offering a comprehensive approach that goes beyond the limitations of single model applications. This methodology not only provides more accurate and comprehensive results, but also serves as a fundamental reference for geological hazard mitigation and management in Liangshan Prefecture, potentially benefiting similar regions worldwide. [ABSTRACT FROM AUTHOR]

Simple Summary: Gonga Mountains stretch latitudinally and locate at the eastern edge of the Qinghai–Xizang Plateau and the center of Hengduan Mountain Range, a global biodiversity hotspot. In this study, 20 amphibian species from seven families and twelve genera were identified in the Gongga Mountains through field investigation and museum specimen retrieval. For the horizontal dimension, the amphibian species composition in the western slope was significantly different from that in the eastern slope. For the vertical dimension, the amphibian species richness displayed a unimodal pattern, peaking at mid elevation, 3300–3700 vs. 1700–1900 m a.s.l. in the western and eastern slopes, respectively. The maximum species diversity occurred in different types of vegetation, i.e., alpine coniferous forests on the western slope, and evergreen broad-leaf forests and coniferous broad-leaf forests on the eastern slope. This discovery highlights the complex biodiversity in the Hengduan, Mountains and underscores the need for targeted management and protection. Amphibians serve as reliable indicators of ecosystem health and are the most threatened group of vertebrates. Studies on their spatial distribution pattern and threats are crucial to formulate conservation strategies. Gongga Mountains, with a peak at 7509 m a.s.l. and running latitudinally, are in the center of the Hengduan Mountains Range and at the eastern steep edge of the Qinghai–Xizang Plateau, providing heterogeneous habitats and varied niches for amphibians. In this study, we combined 83 days of field work with information from 3894 museum specimens that were collected over the past 80 years, and identified twenty amphibian species belonging to seven families and twelve genera by morphology. Of these species, seven were listed in the threatened categories of the Red List of China's Biodiversity and thirteen were endemic to China. Ten species were found on the plateau side (western slope) and eleven species were found on the other side close to the Sichuan Basin (eastern slope). Only one species was found on both sides, indicating different community structures horizontally. The species richness was unimodal vertically and peaking at mid elevation on both sides, with the maximum number (ten vs. nine) of species occurring at 3300–3700 vs. 1700–1900 m a.s.l. and in different types of vegetation. The elevation span and body length of species distributed on both slopes did not show significant differences. These findings help to understand the horizontal and vertical distribution pattern of amphibian diversity, laying a foundation for future biogeographical and conservation research in this area. [ABSTRACT FROM AUTHOR]

This study examines hourly precipitation data from 128 national meteorological observation stations within the Sichuan Basin (SB) spanning 2002 to 2021, focusing on warm-season (May to September) hourly extreme precipitation (HEP) and its events (HEPEs). Significant spatial variability is observed across the SB regarding thresholds, amount, intensity, and frequency of warm-season HEP. HEP predominantly occurs from mid-July to early August, with a higher probability of peak events in the afternoon during these months. HEPEs starting from midnight to early morning tend to have prolonged durations, whereas, in the afternoon, prompt-duration HEPEs lasting within 3 h are more prevalent. Around the basin, the northwest and northeast regions experience HEPEs with higher precipitation amounts but fewer occurrences. The northwestern region encounters shorter-duration HEPEs with greater rainfall intensity, while the northeastern region records a higher frequency of moderate or weak HEPEs lasting ≥ 13 h. Comparatively, the southwestern basin exhibits a higher frequency of nocturnal HEP events characterized by relatively lower rainfall intensity. The eastern Sichuan parallel ridge-valley area in the southeastern basin demonstrates more frequent HEP occurrences with lower rainfall intensities. Additionally, mountainous regions of the southeastern SB and the southern branch of the eastern Sichuan parallel ridge-valley exhibit lower HEPE amounts but greater numbers of events, primarily characterized by prompt-duration events in the afternoon. These findings unveil the diverse spatiotemporal patterns of warm-season HEP and HEPEs within the SB, highlighting the regional variability across different geographical zones. This study provides insights for managing vital resources and timely natural disaster evacuation. [ABSTRACT FROM AUTHOR]

The assessment of soil health through a robust index system having a sufficient number of indicators is an important step toward sustainable crop production. The present study aimed at establishing a minimum data set (MDS) from soil functional and nutritional attributes using a dual index system to evaluate the soil health of farmlands under wheat (Triticum aestivum)–maize (Zea mays) crop rotation in Yanting County, Sichuan, China. Farms from 10 villages in the study area were selected, out of which three sites were considered healthy/ideal sites and used as a reference for the remaining seven targeted sites, and soil samples were collected at depth of 20 cm from these farms. The MDS indicators were selected by using principal component analysis (PCA) followed by Pearson's correlation on 25 attributes. Based on significant values, eight attributes were retained in the final MDS, including the sucrase level, pH, wilting coefficient, water holding capacity, organic matter, NK ratio, total potassium, and available phosphorus. Based on the results, most of the farmland soils in Yanting County were in a healthy condition, accounting for 61.71% of the surveyed samples, followed by sub-healthy, degraded, and weak soils, accounting for 19.64%, 9.71%, and 8.93%, respectively. The values of most of the indicators at the targeted sites were significantly lower than those at ideal sites. Thus, specific steps should be taken by adding soil organic matter, combined with other fertilizers, to enhance the microbial biomass, enzymatic activities, and other biological activities in the soil. [ABSTRACT FROM AUTHOR]

Introduction: Landslide-dammed lake outburst floods (LLOFs) are common natural disasters in high-mountain regions, posing serious safety threats to residents' livelihoods and properties and causing major damage to engineering facilities. Giant landslides and river damming events commonly occur in the Eastern Tibetan Plateau in southwestern China. Dam failure generate LLOFs that form outburst deposits (ODs). This phenomenon is particularly common in some giant ancient landslide-dammed lakes. Methods: This study conducted a detailed investigation of the sedimentary characteristics of large-scale landslide-dammed lake outburst deposits in the Diexi Reach of the Upper Minjiang River and Tangjiashan Reach of the Tongkou River Basin, West Sichuan Plateau, China. Meanwhile, typical evidence of highenergy ODs was recorded. Results and Discussion: The longitudinal distribution of these ODs is similar to an elongated fan-shaped terrace along the river channel, presenting a distinctive sedimentary disordered -- sub-ordered -- ordered sequence from upstream to downstream. Several typical units of "sedimentary facies" are developed in the OD profiles, such as boulder units deposited by high-energy outburst flood (OF) events and the gravel and sand units representing pulsating-flow sedimentary environments during the recession stage. The grain size frequency curves are bimodal, and the granularity accumulated curves are upward convex, which reflect that the detrital characteristics of the sediment source area are mainly composed of coarse gravel and boulders. This indicates that the coarse gravel sediment gradually become decreased from upstream to downstream. Moreover, the OD hydrodynamic intensity displays a gradual weakening, and sediment sorting is improved. From upstream to the downstream, the mean particle-size and sorting of the ODs gradually decrease. The skewness become larger, and the kurtosis of the ODs is distributed in all the types. In addition, the different combinations of quartz sand surface microtextures indicate the transformation from high-to low-energy impacts over a short distance, which is controlled by flood hydrodynamics and regime. Significance: These sedimentary characteristics of ODs explain the hydrodynamic changes during the propagation of OFs, and are also important records for distinguishing between ODs, and "normal" floods. [ABSTRACT FROM AUTHOR]

The popularization and use of green production technology is the key to promoting the sustainable development of agriculture. Exploring the path of promoting farmers' adoption of green production technology has important theoretical and practical significance for promoting the green transformation of agriculture and realizing the high-quality development of agriculture. This study examined the impact of contract performance on the adoption of green production technology in the farmland transfer market based on the characteristics of green production technology. An empirical test was conducted using survey data from Heilongjiang, Henan, Zhejiang, and Sichuan Provinces, which differ in agricultural resource endowment and economic development. The results demonstrated that farmland area was positively associated with the number of green production technologies adopted by farmers and use of straw returning, subsoiling, and soil testing for formula fertilization technology. Moreover, improving the performance rates of farmland transfer contracts strengthened the promotional effect of operation scale on green production technology adoption. Using either contract execution or dispute resolution rates to measure contract performance promoted the adoption of green production technology, particularly for large-scale farmers. Therefore, in the publicity and promotion of agricultural green production technology, the government should not only formulate differentiated promotion strategies and support policies based on resource endowment, but also focus on the construction of rural legal systems, which are helpful for building and maintaining a good farmland market order and performance environment, and create conditions for the durability and stability of technology adoption. [ABSTRACT FROM AUTHOR]

The penultimate deglaciation was characterized by a sub-millennial-scale warm event in the Heinrich Stadial 11(HS11), termed the 134-ka event. However, its precise timing and structure remain poorly constrained due to the lack of high-resolution and precisely dated records. We present an oxygen isotope record of a speleothem with well-developed annual lamina from Zhangjia Cave, located on the north margin of the Sichuan Basin, characterizing Asian summer monsoon (ASM) changes in the 134-ka event, which included an increase excursion of ca. 149 years and decrease excursion of ca. 200 years, inferred from 3.3‰ δ18O variations. This event also divided the weak ASM interval-II (WMI-II), corresponding to HS11, into two stages, the WMI-IIa 132.8–134.1 ka and WMI-IIb 134.4–136.4 ka. With a comparable climatic pattern globally, the 134-ka event is essentially similar to the millennial-scale events in last glacial–deglacial period. Particularly, the observed weak-strong-weak ASM sequence (138.8–132.8 ka) is largely controlled by changes in the Atlantic Meridional Overturning Circulation (AMOC) forced by the meltwater of northern high-latitude ice sheets. Moreover, our results underpin that AMOC, rather than the global ice volume, is more critical to ASM variations during the last two deglaciations. [ABSTRACT FROM AUTHOR]

The Hengduan Mountains Region (HMR) is essential for the future ecological protection, clean energy production, Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern ofmountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices (i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones (regions) is scientifically clarified using geographical detectors. Specifically, the stepwise downscaling pane division method is initially proposed to determine the zoning boundary, alleviating the excessive dependence of the traditional zoning method on subjective experience. Besides, the scheme considers the typical regional characteristics of the complex underlying surface and the high gradient zone of climate-vegetation distribution types in HMR. Consequently, the transition zone with quick climate changes between the plateau temperate and mid-subtropical zones is divided into mountainous subtropics, taking into account the spatial distribution characteristics of climate-vegetation regionalization indices. The regionalization scheme will provide practically theoretical support for agricultural production, ecological protection, major project construction, disaster prevention and relief efforts, and other socioeconomic activities in HMR, serving as a classic case of climate-vegetation regionalization for the alpine and canyon regions with intricate underlying surface, striking regional differences, and lack of ground observations. [ABSTRACT FROM AUTHOR]

Although many studies have investigated the influencing factors of adolescents' Internet gaming addiction, few have investigated the influence factor of exposure to domestic violence, and even fewer have used the General Strain Theory to explain the influence path of exposure to domestic violence on adolescents' Internet gaming addiction. Based on the GST, this study sought to uncover further insights into the effect of exposure to family violence on adolescents' Internet gaming addiction, and the mediating role of social control--specifically, parental attachment--and self-control in the association between exposure to family violence and adolescents' Internet gaming addiction. Adopting a multi-stage cluster random sampling method, we conducted this study with 2,110 adolescents from Liangshan Yi Autonomous Prefecture in Sichuan Province, China. The results suggest that adolescents' exposure to domestic violence directly affects their addiction to Internet games and indirectly affects it by decreasing social control and self-control. The study not only supplements and improves the explanatory framework of General Strain Theory, but makes a significant contribution to research on the causes of Internet gaming addiction. [ABSTRACT FROM AUTHOR]

Objective: To explore the chain-mediated role of sense of career benefit and sense of career mission in the mechanism of psychological flexibility’s effect on nurses’ work engagement. Methods: Adopting the convenience sampling method, 1032 nurses in 10 general hospitals in Sichuan Province were surveyed by questionnaires using the General Information Questionnaire, Sense of Occupational Benefit Scale, Sense of Occupational Mission Scale, Psychological Flexibility Scale, and work engagement Scale in August-October 2022, and the model of the chainedmediated effect was constructed and validated. Results: The total psychological resilience score of nurses in 10 general hospitals in Sichuan Province was (91.29 ± 17.38), the total score of sense of occupational benefit was (137.85 ± 21.02), the total score of sense of occupational mission was (40.27 ± 7.37), and the total score of work engagement was (34.99 ± 9.80). The total score of nurses’ work engagement was positively correlated with the total scores of psychological elasticity, sense of professional benefit, and sense of professional mission (all P < 0.05). The direct effect of psychological elasticity on nurses’ work engagement was significant, with an effect value of 0.321; the chain mediation effects of occupational benefit and occupational mission as separate mediators and the chain mediation effects of the two were 0.039, 0.032, and 0.062, respectively. Conclusion: Nurses’ work engagement in 10 general hospitals in Sichuan province is at a medium level, and occupational benefit and occupational mission play a significant role in the mechanism of the psychological elasticity’s effects on nurses’ work commitment, and the chain mediation effect occupational mission in the mechanism of psychological elasticity is established. The chain mediation effect in the mechanism was established. Managers should pay attention to nurses with low psychological elasticity, improve their sense of occupational benefit, and enhance their sense of occupational mission in order to further promote the enhancement of work engagement. [ABSTRACT FROM AUTHOR]

Deep, unstable slopes are highly developed in mountainous areas, especially in the Minjiang River Basin, Sichuan Province, China. In this study, to reveal their deformation evolution characteristics for stability evaluation and disaster prevention, multi-period optical remote sensing images (2010–2019), SBAS-InSAR data (January 2018–December 2019), and on-site real-time monitoring (December 2017–September 2020) were utilized to monitor the deformation of a large deep-seated toppling, named the Tizicao (TZC) Toppling. The obtained results by different techniques were cross-validated and synthesized in order to introduce the spatial and temporal characteristics of the toppling. It was found that the displacements on the north side of the toppling are much larger than those on the south side, and the leading edge exhibits a composite damage pattern of "collapse failure" and "bulging cracking". The development process of the toppling from the formation of a tensile crack at the northern leading edge to the gradual pulling of the rear edge was revealed for a time span of up to ten years. In addition, the correlation between rainfall, earthquakes, and GNSS time series showed that the deformation of the toppling is sensitive to rainfall but does not change under the effect of earthquakes. The surface-displacement-monitoring method in this study can provide a reference for the evolution analysis of unstable slopes with a large span of deformation. [ABSTRACT FROM AUTHOR]

Southwest China (SWC) possesses complicated topography with frequent geological activities, where heavy precipitation occurs frequently in warm seasons. Few previous studies on extreme precipitation were carried out at hourly scales. In this study, spatiotemporal variations of the extreme hourly precipitation (EHP) over SWC during the warm season of 1981-2020 and the involved mechanisms are investigated. Results show that the threshold and intensity of EHP present similar spatial distribution-lower (higher) in the west (east) part of SWC, while the EHP frequency is opposite. The long-term trend of EHP amount shows a more significant positive tendency than that of hourly precipitation (HP) amount due to synchronous increases in intensity and frequency. The significant increasing trend of EHP occurs in areas above 500-m terrain height, with a weak increasing trend below 500 m (e.g., Chongqing and eastern Sichuan). EHP appears mainly from June to August and exhibits a bimodal distribution in diurnal variation. The mechanism analysis demonstrates that occurrences of EHP are generally accompanied by positive anomalies of temperature, humidity, and geopotential height. Anomalous cyclonic circulation can also be found in the low-level wind field. The westward and northward extension of the western North Pacific subtropical high (WNPSH) as well as temperature rise may be the primary reason for the increase of EHP. For Chongqing and eastern Sichuan, the anticyclone circulation in low-level and the significantly weakened water vapor flux convergence cause poor moisture and dynamic conditions, inhibiting the growth of EHP. SIGNIFICANCE STATEMENT: Heavy precipitation occurs frequently during the warm season in Southwest China (SWC), often causing severe impacts on human safety and economic property. This study analyses spatiotemporal variations of the extreme hourly precipitation (EHP) over SWC during the warm season of 1981-2020 and the involved mechanisms. The increasing trend of EHP far exceeds that of hourly precipitation (HP), especially in areas above 500 m. The westward and northward extension of the western North Pacific subtropical high (WNPSH) and temperature rise may be the main reason for the increase of EHP. For areas below 500 m (e.g., Chongqing and eastern Sichuan), poor moisture and dynamic conditions inhibited the growth of EHP. [ABSTRACT FROM AUTHOR]

Background: Internet addiction, defined as uncontrolled behaviour resulting from the use of the Internet without the influence of addictive substances, which can seriously impair academic, occupational and social functioning. Non-suicidal self-injury, defined as self-injurious behaviour without the intent to die, and its addictive characteristics are similar to those of Internet addiction. Currently, there is a lack of research on the relationship between non-suicidal self-injury and Internet addiction. The purpose of this study was to examine the relationship between non-suicidal self-injury and internet addiction among college students and the role of self-concealment in this relationship. Methods: In this study, data were collected online between December 2022 and January 2023 from 600 university students in Chengdu, Sichuan Province, China, using purposive sampling. The questionnaires included the Non-Suicidal Self-Injury Inventory (NSSI), the Self-Concealment Scale (SCS) and the Internet Addiction Test (IAT). Results: A total of 573 valid questionnaires were recovered, with a valid recovery rate of 95.50%. Conclution: The results suggest that self-concealment plays a partial mediating role between non-suicidal self-injury and internet addiction among college students. The authors emphasized the importance of internet addiction. In order to reduce the occurrence of internet addiction, schools should provide targeted interventions to promote the psychological health of college students' internet addictive behaviours. [ABSTRACT FROM AUTHOR]

At 12:52 (local time, UTC + 08:00) on September 5, 2022, an earthquake of magnitude 6.6 occurred in Luding of the Sichuan Province (southwest China). Combined with the empirical relationship between magnitude and global–local source parameters, the hybrid source model of the Luding earthquake was applied. In a simulation, the source model was mainly described by global source parameters and local source parameters. Based on the empirical relationship between global source parameters and magnitude, we obtained the mean values of global source parameters. In combination with the standard deviation given by the empirical formula, the source parameters satisfying the mean value and standard deviation were generated based on the modified truncated normal distribution function. The observation points were selected considering the various geological conditions and orientations, and then, they were generated based on the acceleration waveforms of the selected observation points using the finite-fault approach through the dynamic corner frequency. Next, their values were used to calculate the acceleration response spectra of these target points. Then, the source model corresponding to the 5% damped pseudospectral acceleration (PSA) with the minimum residual of the average response spectra was selected and is finally set as the optimal source model for the Luding earthquake in China. Finally, the slip distributions of two models were compared, the response spectra were obtained, and the impacts of the two source models on the simulation results were investigated. The results verified the reliability of the source model estimated in this study and showed that the influence of the source model on the simulation results is mainly present in the short period. In addition, the results indicate that the method obtained in this study can be used to quickly predict the source model for earthquake scenarios. [ABSTRACT FROM AUTHOR]

The origin of cosmic rays can be deciphered by accurately measuring the components and energy spectrum in the knee region. Study of Extensive air shower (EAS) relies on information provided by secondary high energy hadrons, which generate evaporation neutrons when they interact with matter in the environment. In the early 21st century, the electron–neutron detector (EN-detector) was developed at the Institute for Nuclear Research of the Russian Academy of Science (INR RAS). The PRImary Spectrum Measurement Array (PRISMA) project was introduced to enhance the array capabilities of cosmic ray composition separation and improve measurement accuracy. Within the framework of Chinese–Russian cooperation, at the Large High Altitude Air Shower Observatory (LHAASO) at Mt. Haizi (4400 m a.s.l.) in Daocheng, Sichuan province, China, a proposal was launched to establish the EN-Detector Array (ENDA) composed of 400 detectors in area of 10000 m to measure cosmic rays up to 300 PeV. In China, in 2018, a cluster, having 16 EN-detectors, was built at Tibet University (TU, 3700 m a.s.l.) in Lhasa, Tibet, to test specification of the array, and later it was moved to the Yangbajing (YBJ) Cosmic Ray Observatory (4300 m a.s.l.) in Tibet. Since 2019, another cluster so called ENDA-16 has started running at LHAASO, and here we give the first result of thermal neutron distribution. After gaining experience from these previous works, in April 2023, we successfully extended ENDA to ENDA-64 composed of 64 EN-detectors in area of 1000 m at LHAASO to measure cosmic rays from 400 TeV to 20 PeV. Here we describe installation and running status of ENDA-64 and present first results of thermal neutron distributions at different locations and hybrid detection of cosmic ray by using ENDA and LHAASO. [ABSTRACT FROM AUTHOR]

Fermentation is the key process required for developing the characteristic properties of cigar tobacco leaves, complex microorganisms are involved in this process. However, the microbial fermentation mechanisms during the fermentation process have not been well-characterized. This study investigated the dynamic changes in conventional chemical composition, flavor compounds, and bacterial community during the fermentation of cigar tobacco leaves from Hainan and Sichuan provinces in China, as well as the potential roles of bacteria. Fermentation resulted in a reduction of conventional chemical components in tobacco leaves, with the exception of a noteworthy increase in insoluble protein content. Furthermore, the levels of 10 organic acids and 19 amino acids showed a significant decrease, whereas the concentration of 30 aromatic substances exhibited a unimodal trend. Before fermentation, the bacterial community structures and dominant bacteria in Hainan and Sichuan tobacco leaves differed significantly. As fermentation progressed, the community structures in the two regions became relatively similar, with Delftia, Ochrobactrum, Rhodococcus, and Stenotrophomonas being dominant. Furthermore, a total of 12 functional bacterial genera were identified in Hainan and Sichuan tobacco leaves using bidirectional orthogonal partial least squares (O2PLS) analysis. Delftia, Ochrobactrum, and Rhodococcus demonstrated a significant negative correlation with oleic acid and linoleic acid, while Stenotrophomonas and Delftia showed a significant negative correlation with undesirable amino acids, such as Ala and Glu. In addition, Bacillus showed a positive correlation with benzaldehyde, while Kocuria displayed a positive correlation with 2-acetylfuran, isophorone, 2, 6-nonadienal, and β-damascenone. The co-occurrence network analysis of microorganisms revealed a prevalence of positive correlations within the bacterial network, with non-abundant bacteria potentially contributing to the stabilization of the bacterial community. These findings can improve the overall tobacco quality and provide a novel perspective on the utilization of microorganisms in the fermentation of cigar tobacco leaves. [ABSTRACT FROM AUTHOR]

Maoxian Country in Sichuan Province, China is a quake-prone mountainous area. Within 300 km of it, there have been more than ten strong earthquakes higher than Ms6.0 on record. The nearest one is the Diexi Earthquake of 1933, 8.7 km from Maoxian County. A catastrophic scale landslide, the Xinmo landslide, took place on the steep cataclinal slope of Xinmo Village on June 24, 2017. Shear failure happened to the phyllite layer of rich fissures during the landslide. In this paper, shaking table tests have been conducted on the Xinmo landslide as a prototype, and a non-contact deformation measurement based on the digital image correlation (DIC) technique has been made to analyze the dynamic response and deformation of the slope under accumulated seismic actions. As the results, stress amplification is found at the end of joints on the potential slide face. Failure starting from the middle of the potential slide face in the beginning extends upwards and downwards along the face, and leads to a steep tension crack on the top of the slope and a buckling failure of radial-arc cracks at the foot. A semi-steep radial crack in buckling part has a shear failure. The tensile stress amplification on the discontinuous face contributes to the failure accumulation of it and asymptotic failure of the slope. It proposed that the closure and downward displacement of tensile crack on the top of slope, buckling phenomenon at the foot of slope and shear failure of semi-steep crack are all the bad omens of landsliding. [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 development of a farmland transfer market and the spatial characteristics of transfer plots are crucial factors influencing chemical input reduction in agricultural production with relation to the endowment of fragmented agricultural land resources. Through a theoretical discussion, this study analyzed the heterogeneity of transfer plots' spatial characteristics and their effect on the intensity of chemical input in agricultural production in the process of farmland transfer. Plot-level survey data from the Heilongjiang, Henan, Zhejiang, and Sichuan provinces were used for empirical analysis. The results indicated that the values of pesticide and fertilizer input in the large plot group were CNY 10.154 and CNY 8.679 lower than those in the small plot group, respectively. Additionally, compared with non-adjacent plots, the per-unit area input was CNY 2.396 and CNY 6.691 lower in adjacent plots. This indicated that plot area expansion and location adjacence significantly reduced the intensity of pesticide application and fertilizer input in the plots. Simultaneously, location linkage reduced chemical input in agricultural production in small plots; however, the difference was unnoticeable in large plots. This study provides a theoretical basis for promoting farmland integration in China as well as introduces a specialized method for reducing agricultural chemical usage. [ABSTRACT FROM AUTHOR]

Diarrhea caused by enterotoxigenic Escherichia coli (ETEC) infections poses a significant challenge in global pig farming. To address this issue, the study was conducted to identify and characterize 19 ETEC isolates from fecal samples of diarrheic pigs sourced from large-scale farms in Sichuan Province, China. Whole-genome sequencing and bioinformatic analysis were utilized for identification and characterization. The isolates exhibited substantial resistance to cefotaxime, ceftriaxone, chloramphenicol, ciprofloxacin, gentamicin, ampicillin, tetracycline, florfenicol, and sulfadiazine, but were highly susceptible to amikacin, imipenem, and cefoxitin. Genetic diversity among the isolates was observed, with serotypes O22:H10, O163orOX21:H4, and O105:H8 being dominant. Further analysis revealed 53 resistance genes and 13 categories of 195 virulence factors. Of concern was the presence of tet(X4) in some isolates, indicating potential public health risks. The ETEC isolates demonstrated the ability to produce either heat-stable enterotoxin (ST) alone or both heatlabile enterotoxin (LT) and ST simultaneously, involving various virulence genes. Notably, STa were linked to human disease. Additionally, the presence of 4 hybrid ETEC/STEC isolates harboring Shiga-like toxin-related virulence factors, namely stx2a, stx2b, and stx2e-ONT-2771, was identified. IncF plasmids carrying multiple antimicrobial resistance genes were prevalent, and a hybrid ETEC/STEC plasmid was detected, highlighting the role of plasmids in hybrid pathotype emergence. These findings emphasized the multidrug resistance and pathogenicity of porcine-origin ETEC strains and the potential risk of epidemics through horizontal transmission of drug resistance, which is crucial for effective control strategies and interventions to mitigate the impact on animal and human health. [ABSTRACT FROM AUTHOR]

On September 5, 2022 (local time), a magnitude 6.6 earthquake was reported to have occurred in Luding County, Sichuan Province, Southwest China. In this simulation, a widely used stochastic finite-fault model was used to analyze how the source models affect the near-fault earthquake ground motion simulations of the 2022 Mw 6.6 Luding earthquake in China. Seven different slip models, one of them obtained from common fault parameters and random distributed slip amount, were used to yield the best match with the recordings. The simulated earthquake ground motions calculated in the frequency band of 0.05–20 Hz were compared with the observed values in both the time and frequency domains. Twelve acceleration observation stations located near the fault plane were selected in our simulation for comparison. The average H/V curves were estimated using the available acceleration records to consider the local site effect at each selected station. The research results indicate that none of the source models adopted in this study fully estimate the observed values at all the selected ground-motion stations. The simulated values of some slip models underestimate the level of the Fourier amplitude spectrum at frequencies above 6 Hz. The underestimation may be attributed to the directivity effect, which may produce a higher amplitude of observed ground motion in the high-frequency band. All the slip models show similar average model deviations except for the random slip model. Finally, the peak ground accelerations and peak ground velocities were predicted at these selected near-fault observation stations. The results indicate that the peak accelerations and velocities obtained from seven slip models correlate well with each other, but are slightly lower than the recorded values at most stations. In addition, the synthetized results calculated from the random and inverted slip models can be the same level only if a greater stress drop is adopted in the random model. [ABSTRACT FROM AUTHOR]

Degradation in farmland quality owing to overuse emphasizes the current need for the adoption of protective technologies to ensure food security and sustainable resource utilization. This study employs plot survey data from Heilongjiang, Henan, Zhejiang, and Sichuan provinces in China to investigate how the spatial attributes of transferred plots influence the current adoption of farmland protection methods, such as deep tillage and straw-returning. Findings reveal that larger or interconnected transferred plots significantly increase the likelihood of farmers adopting conservation tillage technologies. However, the influence of the plot's location on technology adoption varies among different plots. As the farmland transfer market expands, the spatial features of these plots emerge as critical determinants in the use of protective technologies. This underscores the pressing need for an integrated farmland transfer trading system and strengthened policy measures promoting land consolidation to foster widespread adoption of these conservation strategies. [ABSTRACT FROM AUTHOR]

Dynamic monitoring and evaluation of vegetation ecological quality (VEQ) is indispensable for ecological environment management and sustainable development. Single-indicator methods that have been widely used may cause biased results due to neglect of the variety of vegetation ecological elements. We developed the vegetation ecological quality index (VEQI) by coupling vegetation structure (vegetation cover) and function (carbon sequestration, water conservation, soil retention, and biodiversity maintenance) indicators. The changing characteristics of VEQ and the relative contribution of driving factors in the ecological protection redline areas in Sichuan Province (EPRA), China, from 2000 to 2021 were explored using VEQI, Sen's slope, Mann-Kendall test, Hurst index, and residual analysis based on the XGBoost (Extreme gradient boosting regressor). The results showed that the VEQ in the EPRA has improved over the 22-year study period, but this trend may be unsustainable in the future. Temperature was the most influential climate factor. And human activities were the dominant factor with a relative contribution of 78.57% to VEQ changes. This study provides ideas for assessing ecological restoration in other regions, and can provide guidance for ecosystem management and conservation. [ABSTRACT FROM AUTHOR]

Natural fractures are of paramount importance in storing carbon in shale oil reservoirs, where ultra-low porosity and permeability necessitate their essentiality for enhanced oil recovery. Therefore, comprehensively clarifying the characteristics of natural fractures in shale oil reservoirs is imperative. This paper focuses on investigating the microscopic features of natural fractures in organic-rich continental shale oil reservoirs that are commonly found in the Lower Jurassic strata of the Sichuan Basin, employing them as a representative example. Multiple methods were utilized, including mechanical testing, Kaiser testing, multi-scale CT scanning (at 2 mm, 25 mm, and 100 mm scales), and a numerical simulation of fluid seepage in fracture models. The results revealed that the in situ stress of the target seam displays the characteristic of σH > σv > σh, with σv and σh being particularly similar. The relatively high lateral stress coefficient (ranging from 1.020 to 1.037) indicates that the horizontal stresses are higher than the average level. Although the 2 mm CT scan provides a more detailed view of fractures and connected pores, it primarily exhibited more pore information due to the high resolution, which may not fully unveil additional information about the fractures. Thus, the 25 mm shale core is a better option for studying natural fractures. The tortuosity of the different fractures indicated that the morphology of larger fractures is more likely to remain stable, while small-scale fractures tend to exhibit diverse shapes. The simulations demonstrated that the stress sensitivity of fracture permeability is approximately comparable across different fracture scales. Therefore, our research can enhance the understanding of the properties of natural fractures, facilitate predicting favorable areas for shale oil exploration, and aid in evaluating the carbon storage potential of shale oil reservoirs. [ABSTRACT FROM AUTHOR]

The summer precipitation over the southeastern Tibetan Plateau (SETP) exhibits significant diurnal variability, with a notable peak before midnight. This study investigates how thermally forced circulations regulate the diurnal precipitation over the SETP, using surface rain‐gauge observations and high‐resolution reanalysis data from June to August during 2015–2019. Water vapor supply and precipitation onset in the afternoon are associated with the upslope winds and upward motions of the mountain–plains solenoid (MPS) between the SETP and nearby lowlands (the Sichuan Basin and Yunnan–Guizhou Plateau). After sunset, the sustained easterly and stronger southerly winds below 500 hPa transport abundant moisture from the rainy lowlands to the SETP. The findings suggest that these winds are mainly due to the larger zonal continental‐scale thermally forced circulation combined with the meridional large‐scale MPS before midnight and the meridional small‐scale MPS after midnight. Plain Language Summary: The summer rainfall over the southeastern Tibetan Plateau (SETP) is crucial to the hydrological cycle of both the SETP and nearby regions. However, it remains unclear why the rainfall over the SETP mostly occurs at night due to limited observations. This study aims to investigate the role of thermally driven winds in diurnal rainfall during summer (June–August) over the SETP, using high‐resolution reanalysis data and surface rain‐gauge observations. The results show that the strong upward motions and low‐level upslope winds of the thermally forced mountain‐valley wind systems (MVWS) between the SETP and the lowlands (Sichuan Basin and Yunnan–Guizhou Plateau) help to trigger the precipitation and transport moisture in the afternoon. After sunset, thermally forced circulations, including the east–west continental‐scale thermal circulation between the Asian continent and its adjacent ocean, the north–south large‐scale MVWS between the Yunnan–Guizhou Plateau and its southern plain, and the north–south small‐scale MVWS between the SETP and its southern slope, help maintain horizontal winds from the rainy lowlands, transporting abundant moisture to facilitate the rainfall over the SETP at night. Key Points: Thermally forced circulations greatly impact the diurnal cycle of summer precipitation over the southeastern Tibetan Plateau (SETP)Daytime rainfall over this region is associated with the upward motions and upslope winds of the mountain–plains solenoidMulti‐scale thermal circulations are responsible for moisture transport of nighttime rainfall over the SETP [ABSTRACT FROM AUTHOR]

(1) Background: The tense relationship between man and land makes transferring farmland rights in the market critical for improving agricultural production efficiency and promoting large-scale agricultural management. (2) Methods: This study considers the impact of the spatial characteristics of farmland plots on the economies of scale of farmers in terms of farmland use and heterogeneity. The effect of plots' area and location on the directional flow of plots in the farmland transfer market from the perspective of matching supply and demand is also investigated. An empirical test is conducted on farmer actions and plot characteristics data based on surveys from 2015 and 2018 in the Chinese provinces of Heilongjiang, Henan, Zhejiang, and Sichuan. (3) Results: The plots' area and location affect economies of scale for different potential transfer plots. This leads to large plots and adjacent plots in the market transferring to large-scale households, while scattered small plots mainly transfer to ordinary households. (4) Conclusions: The fixed spatial characteristics of the plots determine the scattered circulation of farmland in the transfer market, hindering the centralized utilization of farmland and restricting efficiency in farmland transfer market allocation. The findings from the context of China are similar to what has been found elsewhere. This suggests the need for a unified trading platform for farmland transfer and strengthening the mutual transformation of land and agricultural machinery. [ABSTRACT FROM AUTHOR]

BACKGROUND: The diamondback moth (DBM) Plutella xylostella has developed resistance to almost all insecticides used to control it. Populations of DBM in temperate regions mainly migrate from annual breeding areas. However, the distribution pattern of insecticide resistance of DBM within the context of long-distance migration remains unclear. RESULTS: In this study, we examined the frequency of 14 resistance mutations for 52 populations of DBM collected in 2010, 2011, 2017 and 2018 across China using a high-throughput KASP genotyping method. Mutations L1041F and T929I conferring pyrethroid resistance, and mutations G4946E and E1338D conferring chlorantraniliprole resistance were near fixation in most populations, whereas resistant alleles of F1020S, M918I, A309V and F1845Y were uncommon or absent in most populations. Resistance allele frequencies were relatively stable among different years, although the frequency of two mutations decreased. Principal component analysis based on resistant allele frequencies separated a southern population as an outlier, whereas the immigrants clustered with other populations, congruent with the migration pattern of northern immigrants coming from the Sichuan area of southwestern China. Most resistant mutations deviated from Hardy–Weinberg equilibrium due to a lower than expected frequency of heterozygotes. The deviation index of heterozygosity for resistant alleles was significantly higher than the index obtained from single nucleotide polymorphisms across the genome. These findings suggest heterogeneous selection pressures on resistant mutations. CONCLUSION: Our results provide a picture of resistant mutation patterns in DBM shaped by insecticide usage and migration of this pest, and highlight the widespread distribution of resistance alleles in DBM. [ABSTRACT FROM AUTHOR]

It is well documented that temperatures higher than 400 ℃ can significantly lower rock strength due to thermally induced decomposition and microcracks. However, rock strength increase under temperatures 25–400 ℃ has also been reported. It remains elusive whether thermal strengthening does exist or it is just an illusion caused by rock heterogeneity. To uncover such a mystery, we carried out triaxial compression tests on Sichuan marble under 25–200 ℃. Rock heterogeneity was at a low level and data dispersion was limited in our experiment. We managed to observe a clear trend of strength increase with temperature, justifying the existence of thermal strengthening in Sichuan marble. To unveil the mechanism of thermal strengthening, five factors, as predominant and comprehensive as we could concern, were investigated. After careful examination and analysis, thermal expansion was inferred to be the main reason leading to the thermal strengthening in Sichuan marble. The mechanism may lie in tighter compaction between mineral grains due to thermal expansion. Since thermal expansion is a physical process that can occur in all crystalline rocks upon heating, thermal strengthening holds a high potential to be a general property of crystalline rocks in the moderate temperature range. To our best knowledge, this study is the first to explicitly confirm the existence of thermal strengthening and comprehensively investigate the underlying mechanisms. The findings provide a new understanding of the thermal effect on rock strength, which may aid rock engineering design under a thermo-mechanical coupling working condition. Highlights: Triaxial compression tests were performed on Sichuan marble specimens in the temperature range 25–200 ℃. Rock heterogeneity was at a low level and thermal strengthening in Sichuan marble was confirmed. Thermal expansion is inferred to be the leading factor of thermal strengthening in Sichuan marble after a comprehensive investigation. [ABSTRACT FROM AUTHOR]

Wasabi (Eutrema japonicum), also known as Japanese horseradish, is a perennial herb widely used in Japanese cuisine for its special flavour. The health-promoting phytochemicals and antioxidant capacity of four organs (leaf, petiole, rhizome, and root) of two cultivars (Chuankui--1 and Chuankui--2) of wasabi from two producing areas, Leibo and Guangyuan in Sichuan Province, China, were investigated in this study. The results showed that leaves were rich in pigments, soluble protein, ascorbic acid, and total phenolics and had the highest antioxidant capacity. Soluble sugars were highest in the petioles and were 1.1- to 5-fold higher than those in the other three organs. Glucosinolates and glucosinolate breakdown products (GBPs) were the most abundant in rhizomes, and their maximum values were 271.61 mmol kg-1 DW and 249.78 mmol kg-1 DW, respectively. The rhizomes of Chuankui--1 in Leibo and the leaves of Chuankui--1 in Guangyuan were superior in terms of glucosinolates and GBPs. These findings provide new insights that will aid the use of wasabi cultivars; they also have implications for the environmental characteristics needed to obtain better quality wasabi products. In the future, metabolome and transcriptome can be used to analyze the potential mechanism of differences among typical varieties, origins and parts. [ABSTRACT FROM AUTHOR]

Land-use change is an important research topic in global environmental change. Analyzing land-use change and its driving factors can aid in the evaluation of the current and the determination of future land-use policies. This study took Mao County, Southwest China, as the study area and used the land-use change and statistical data surveyed in 2009 and 2019. With the help of geographic information system technology, a land-use transfer matrix was used to comprehensively analyze the characteristics of spatiotemporal differentiation of land use, while the driving mechanism was analyzed by constructing the influencing factors using a geographical detector model. The results showed that the change in land use in Mao County was drastic. The increasing land types included orchards, grasslands, built-up lands, and water bodies, whereas the decreasing land types included croplands, forestlands, and unused lands. The main driving factors of land-use transition depended on the type of land-use change. Elevation, distance from the county government, and population were the main driving factors of land-use change. Road density, distance from the river, distance from the town/township government, and gross domestic product also affected land-use change to a certain extent, whereas relief and slope had less impact. [ABSTRACT FROM AUTHOR]

Earthquakes have occurred frequently in western China (Sichuan, Tibet, etc.) while the complex site conditions in western regions bring great uncertainty to the seismic performance of isolated high-speed railroad bridges (HSRBs). By studying the relationship between structure-dependent and structure-independent seismic intensity measures, soil site conditions are taken into account in the probabilistic seismic demand model (PSDM), which is applied to analyze the failure probability of the isolated HSRB under different site conditions. Based on the design parameters and test results of a typical isolated HSRB in western region, the analysis of the finite element model of the structure was performed. Probabilistic seismic demand models of the isolated HSRB were developed. The seismic fragility curves of the isolated HSRBs were obtained and the failure probabilities under different site conditions were compared and analyzed. The evaluation of the failure probability that the failure probability of the isolated HSRBs in the site area with seismic intensity of 9 is 35.84% and 78.19% under the soil site categories D and E, respectively. Therefore, the seismic spectrum characteristics of the soil site are an important factor affecting the seismic response of isolated HSRB structures. This study provides a more effective modified PSDM for seismic performance assessment of isolated HSRBs under the different site conditions. [ABSTRACT FROM AUTHOR]

Landslide is regarded as one of the most prevalent and destroying geological hazards in natural terrain areas. Reliable landslide susceptibility analysis procedures are vital for policymakers to manage the regional-scale landslide risk. In the framework of physically based modelling analysis, the infinite slope model is commonly used to assess the surficial landslide susceptibility with deterministically defined geotechnical and geological parameters. This work aims to develop a user-friendly geographic information system (GIS) extension tool called the GIS-FORM landslide prediction toolbox using the Python programming language to consider the possible uncertainties in the physically based landslide susceptibility analysis in seismic areas. We implement the first-order reliability method (FORM) algorithm to calculate the probability of infinite slope failures. The proposed toolbox can produce some regional hazard distribution maps of different indexes, such as the factor of safety (FoS), reliability index (RI), and failure probability (Pf). Furthermore, the toolbox enables coseismic landslide displacement prediction using either the direct Newmark integration method and/or the empirical formula method. Outputs of the GIS-FORM landslide prediction analysis are verified using published data in the literature. Further, it is also successfully employed for landslide susceptibility analysis of the Ms 7.0 Jiuzhaigou earthquake in Sichuan Province, China. Without loss of generality, the GIS-FORM landslide prediction toolbox can serve for the rapid hazard mapping of earthquake-induced regional landslides where uncertainties in geological and geotechnical parameters should be considered. [ABSTRACT FROM AUTHOR]

Comprehensive, spatially explicit understanding of N loss from N input in China's maize (Zea mays L.) belt is needed to improve N management and develop N loss mitigation measures for specific locations. However, accurate estimation of N loss remains uncertain mainly because of spatial heterogeneity of emission factors (EFs) and activity data. Here, we built random‐forest models to predict EFs for each N loss pathway (dinitrogen, nitric oxide, nitrous oxide and ammonia emissions, nitrate leaching, and N runoff) considering soil and climate factors. We then used location‐ and crop‐specific activity data to understand N loss and surplus on a 1‐ × 1‐km grid. Results showed that the N surplus and total N loss averaged 135.4 (95% confidence interval [CI], 36.6–261.5) and 87.6 (95% CI, 32.9–162.5) kg N ha–1, respectively, and nitrate leaching and ammonia emissions were primary loss pathways. There was a significant correlation between N surplus and total N loss in spatial distribution, and regions with high N surplus and total N loss were mainly in the northern China Plain and Sichuan Basin, while regions with low surplus and loss could be found in Heilongjiang and Jilin provinces. Our results are beneficial to understand specific crop N budget and develop location‐specific N management strategies. Core Ideas: A spatially explicit assessment of N loss from N input was mapped in China's maize belt.The N surplus and total N loss averaged 135.4 and 87.6 kg N ha‐1, respectively.High N surplus and total N loss was recorded in the northern China Plain and Sichuan Basin. [ABSTRACT FROM AUTHOR]

The detection of the formation of pore pressure while drilling is of great importance to ensure safe drilling operations. At present, the dc-exponent concept is mainly used to detect pore pressure while drilling. The dc-exponent concept is based on the theory of shale compaction, which is limited when used in carbonate rocks. A mechanical specific energy (MSE)-based method is proposed to detect pore pressure in deep, complex intervals. The method is based on the theory that the energy consumed by the bit to break and remove a unit volume of rock can reflect the effective stress and pore pressure of the rock in situ. In this paper, a torque and weight on bit (WOB) transfer model is proposed for estimating the downhole torque and WOB using drill string mechanics. Meanwhile, the rotary speed and torque of the positive displacement motors under compound drilling are considered, and the model of total MSE under compound drilling is modified. The MSE-based method was used to estimate the pore pressure in a region in western Sichuan, and there is a good agreement between the detected and measured pore pressure. The results demonstrate that the accurate computed MSE-based method is useful in detecting pore pressure in deep complex intervals. [ABSTRACT FROM AUTHOR]

The Luchedu rock avalanche (LRA) that occurred in 1935 at the junction of Sichuan and Yunnan in Southwest China is a disaster chain of the rock slide, debris avalanche, and river blocking induced by heavy rainfall. The rock slide originated from the wedge formed by sheet metamorphic rocks on the fault zone on the left bank of the Jinsha River. After breaking away from the slope, the wedge disintegrated and cracked rapidly, forming debris and causing them to flow in fluidization along a 7.3 km path. After the obvious entrainment process and curve superelevation in the proximal area, the deposition reached 50.5 × 10 6 m3 in the distal area. The sedimentary structure of clasts has typical stratification characteristics. The types of sedimentary facies include carapace facies, body facies, and mixed facies. Inside the sedimentary structure, dense shear zones, liquefied intercalations, jigsaw structures, and directional arrangement of particles are observed. Through a detailed geological survey and DEM spatial analysis, the avalanche entrainment rate of LRA was determined as 1.2. The morphological fluctuation of basement lithology and gully path plays an important role in the long-distance movement. The rock fragments formed by metamorphic rocks with a primary schistosity structure can effectively reduce the energy loss in the internal shear process and significantly promote the laminar flow movement in the distal region of the avalanche. Therefore, as a giant rock avalanche formed by the evolution of specific metamorphic rocks, LRA results from the combination of macrohydrodynamics and microrock failure properties. [ABSTRACT FROM AUTHOR]

With the continuous increase in the amount of mulch film, "white pollution" caused by plastic fragments (PF) has seriously affected agricultural production progress and poses a great threat to the safety and health of the agricultural environment. In the present study, PFs collected from 20 mulched agricultural farmlands in Sichuan Province were investigated. The PFs were separated and screened following the density flotation method. Optical microscopy was used to assess the fragments' distribution, abundance, color, size, and morphology, and Raman spectroscopy was used to identify the types. In addition, through the analysis of a questionnaire survey, a random forest (RF) model was conducted to assess the effects of environmental factors on the amount of PF. The results showed that the abundance of PFs was the highest in Lade Town, Zigong City, reaching 1158.33 ± 52.04 particles kg−1. Meanwhile, PFs were less abundant in Foyin Town, Luzhou City, with 50.00 ± 25.00 particles kg−1; the morphology features of PF in the cultivated soil were mainly transparent (60.06%) and flaky-like (83.41%), with sizes < 5 mm (63.61%). In total, 75% of the representative PFs were PE PFs, while PVC PFs were 25%. The RF model indicated that there were significant effects due to the total mulch film amount, annual precipitation, and planting pattern on the number of derived residues (PF). This study provides data indicating the urgent need to prevent and control plastic pollution in mulch farming, specifically in the soils of Sichuan Province. [ABSTRACT FROM AUTHOR]

Shidaguan slope (hereinafter short for SDG slope) is an unstable rock slope with an area of 30.78 × 104 m2 and a deformation depth of 30–70 m in Maoxian County, Sichuan Province, China. Three seismometers (P2–P4) with high sensitivity were installed at different locations on the unstable part of the slope. P2 and P3 were almost at the same elevation (2221 m and 2247 m), while P4 was the lowest (at 2140 m). Another seismometer (P1) sat in a stable location at a higher elevation (2373 m). Ninety-nine shallow earthquakes were analyzed. According to the peak acceleration ratios of three seismometers (P2–P4) on the unstable part and another seismometer (P1) on the stable part, the points at lower elevations showed greater seismic amplification (with the amplification coefficient of 2.64–3.51) than one at a higher elevation. In addition, points at relatively thinner part (23 m thick) of unstable slope showed greater seismic amplification than ones at thick part (60–75 m thick). The same rule was also found in studying the site-epicenter azimuth and earthquake magnitude data. Based on the relationship between amplification coefficient and resistivity and rock core, the seismic response amplification was affected by the lithofacies difference. The lithofacies with resistivity values of 50–100 Ω m and RQD values of 0–50% incurred seismic response amplification, which was restrained by the below lithofacies with resistivity values of 10–50 Ω m and ROD values of 0%. When building on slope areas, the lithofacies difference should be taken into full consideration. [ABSTRACT FROM AUTHOR]

Terrestrial red beds are extensively developed in the Upper Jurassic of the Sichuan Basin, southern China, where few fossils have been documented. Recently, abundant silicified wood specimens were found in the central Sichuan Basin, but no plant foliage fossils have been recorded from the same strata. Here, we report the first leafy shoot fossils collected from the red beds of the Upper Jurassic Penglaizhen Formation in Shehong City, central Sichuan Basin. Based on careful comparisons with potential Mesozoic conifer fossils, they were assigned to Pagiophyllum, an extinct conifer taxon of the family Cheirolepidicaceae. The generic classification agreed with the palaeovegetation features of the Penglaizhen Formation which were represented by gymnosperms of Araucariaceae (Agathoxylon‐type wood) and Cheirolepidiaceae (Brachyoxylon‐type wood). The non‐coexistence between the leafy shoot fossil and the petrified wood depicted a unique process of fossil preservation, which may be related to the palaeo‐flood events in this area. The palaeoclimate background during the Late Jurassic of Shehong was suggested to be a hot and semi‐arid or arid condition, supported by the Classopollis‐dominated (75–90%) pollen assemblage from the Penglaizhen Formation. The fossil foliage was collected from lacustrine or fluvial sediments. This suggests that the rainy season is a key factor in the development of regional lakes or rivers and flood events, which offered a suitable local environment for plant growth and helped construct a more complex ecological system, allowing a variety of creatures to survive in the central Sichuan Basin area. [ABSTRACT FROM AUTHOR]

Understanding the regional distribution characteristics of ecological service values (ESV) and their driving factors can provide background information and scientific basis for regional environmental protection policy. This paper adopted the revised equivalent factor method to calculate the ESV of Sichuan province in 2015 and 2020, and the spatial distribution and variation characteristics of the ESV were identified accordingly. Then, the structural equation model (SEM) was used to explore the effects of socioeconomic factors on ESVs in Sichuan Province. The results show that the ESV in Sichuan Province increased by 2521.45 million USD during the period, an increase of approximately 0.67%. The western area had higher ESV values compared to the eastern area, with eastern Sichuan showing a downward trend and the cities in western Sichuan showing an upward trend. The factors of population, affluence, and science and technology can indirectly affect ESV through affecting land use and cover, and this indirect effect is stronger than the direct effect on regional ESV. Among them, the effect of population is the strongest, followed by affluence, and science and technology is the weakest. The result of this paper also suggests that it is necessary to propose differentiated ecological protection policies in eastern and western Sichuan Province to achieve the coordinated development of society, economy, and environment. [ABSTRACT FROM AUTHOR]

A quantitative understanding of changes in water resources is crucial for local governments to enable timely decision-making to maintain water security. Here, we quantified natural-and human-induced influences on the terrestrial water storage change (TWSC) in Sichuan, Southwest China, with intensive water consumption and climate variability, based on the data from the Gravity Recovery and Climate Experiment (GRACE) and its Follow-on (GRACE-FO) during 2003–2020. We combined the TWSC estimates derived from six GRACE/GRACE-FO solutions based on the uncertainties of each solution estimated from the generalized three-cornered hat method. Metrics of correlation coefficient and contribution rate (CR) were used to evaluate the influence of precipitation, evapotranspiration, runoff, reservoir storage, and total water consumption on TWSC in the entire region and its five economic regions. The results showed that a significant improvement in the fused TWSC was found compared to those derived from a single model. The increase in regional water storage with a rate of 3.83 ± 0.54 mm/a was more influenced by natural factors (CR was 53.17%) compared to human influence (CR was 46.83%). Among the factors, the contribution of reservoir storage was the largest (CR was 42.32%) due to the rapid increase in hydropower stations, followed by precipitation (CR was 35.16%), evapotranspiration (CR was 15.86%), total water consumption (CR was 4.51%), and runoff (CR was 2.15%). Among the five economic regions, natural influence on Chengdu Plain was the highest (CR was 48.21%), while human influence in Northwest Sichuan was the largest (CR was 61.37%). The highest CR of reservoir storage to TWSC was in Northwest Sichuan (61.11%), while the highest CRs of precipitation (35.16%) and evapotranspiration (15.86%) were both in PanXi region. The results suggest that TWSC in Sichuan is affected by natural factors and intense human activities, in particular, the effect of reservoir storage on TWSC is very significant. Our study results can provide beneficial help for the management and assessment of regional water resources. [ABSTRACT FROM AUTHOR]

A moment magnitude (M w) 5.0 earthquake hit Qiaojia, Yunnan, China on 18 May 2020. Its hypocentre is only approximately 20 km away from the Baihetan reservoir, the second largest hydropower station in China. The Baihetan Reservoir is located at the junction of multiple fault zones on the eastern boundary of the Sichuan-Yunnan rhombic block, an area with high background seismic activity. The Baihetan Reservoir was planned to be impounded in April 2021 and the M w 5.0 earthquake occurred during its water-retaining. Thus, it is critical to investigate the seismogenesis of the Qiaojia M w 5.0 main shock and evaluate the risk of inducing earthquakes near the Baihetan Reservoir after impoundment. In this study, we built a complete and accurate earthquake catalogue to analyse seismicity in the reservoir area before and after the M w 5.0 Qiaojia earthquake. We adopted a machine learning-based seismic phase picker, PhaseNet, to automatically detect seismic picks from continuous raw seismic data. Seismic phase picks were associated and located using sequential earthquake association and location methods, including REAL, VELEST and hypoDD. We eventually obtained high-precision locations of 1640 earthquakes by the hypoDD. The distribution of earthquake locations indicates that a concealed fault nearly vertical to the surface accommodated the M w 5.0 Qiaojia main shock. The majority of its aftershocks is located within a narrow depth range of 8–13 km, indicating that the stresses in the hypocentral area were concentrated near the hypocentre of the M w 5.0 earthquake. Along with focal mechanism solutions, we suggested that the M w 5.0 Qiaojia earthquake is more likely a tectonic earthquake. However, we cannot exclude the possibility that earthquakes could be induced after the impoundment of Baihetan Reservoir, because the identified concealed fault is located in the middle of many large fault zones and only 20 km away from the Baihetan Reservoir. [ABSTRACT FROM AUTHOR]

Background: The Alphapapillomavirus 9 (α-9 HPV) is a member of the Alphapapillomavirus genus and Papillomaviridae family. These viruses are almost all carcinogenic HPV, which is closely related to 75% of invasive cervical cancer worldwide, and has a high prevalence in Sichuan. The carcinogenic function is mainly realized by its E6 oncoprotein. Methods: Cell samples were collected by cervical scraped for HPV detecting and typing. HPV-16, HPV-31, HPV-33, HPV-52, HPV-58 5 α-9 genus HPV subtype positive samples were selected, their E6 gene was sequenced and analyzed. The positive selection sites of HPV E6 genes were estimated by PAML 4.8 server. The secondary and tertiary structure of E6 protein were predicted by PSIPred and Swiss-model. The T-cell antigen epitopes of E6 protein were predicted by IEDB. Results: α-9 HPV has a high prevalence in Sichuan, China. From 2012 to 2017, 18,067 cell cervical samples were collected, and 3135 were detected with α-9 HPV infection. Among which, 250 cases HPV-16 E6, 96 cases HPV-31 E6, 216 cases HPV-33 E6, 288 cases HPV-52 E6 and 405 cases HPV-58 E6 were successfully amplified, 17, 6, 6, 13, and 4 non-synonymous nucleotide mutations were respectively detected in HPV-16, 31, 33, 52, and 58 E6, 7 positive selection sites of α-9 HPV E6 were selected out (D32E of HPV-16 E6, K35N, K93N and R145I of HPV-33 E6, K93R of HPV-52 E6, K93N and R145K of HPV-58 E6). The structure and antigen epitopes of E6 protein with amino acid substitution differ from those of wild-type E6 protein, especially for the mutation located in the E6 positive selection site. Conclusions: HPV E6 nucleotide non-synonymous mutation in the positive selection site influence the protein structure and decrease the antigen epitopes affinity of the E6 protein overall, making it more difficult for the HPV-infected cells to be detected by the immune system, and enhancing the HPV adaptability to the environment. Mutations influence the validity of HPV clinical diagnostic probes, the polymorphism analysis of α-9 HPV E6 enrich the data of HR-risk HPV in Sichuan China, and the detection probes designed with the polymorphism data in mind can improve the efficiency of clinical detection; Mutations influence epitopes affinity, the association of E6 polymorphism and epitope affinity can improve the design of therapeutic vaccine with good immunity and high generality antigen epitope; The above study all provide a good theoretical basis for the prevention and treatment of HPV-related diseases. [ABSTRACT FROM AUTHOR]

Objectives: To investigate nurses' behavioral intention toward caring for COVID-19 patients on mechanical ventilation, as well as the factors affecting their intention. Background: COVID-19 patients undergoing mechanical ventilation have many care needs and pose more challenges for nurses, which might adversely affect nurses' intention toward caring behavior. Methods: A cross‐sectional study was conducted by using simple random sampling to recruit 598 nurses from five tertiary hospitals in Sichuan Province, China. The participants responded to an online questionnaire that included questions on demographic characteristics; the Attitude, Subjective Norms, and Behavioral Intention of Nurses toward Mechanically Ventilated Patients (ASIMP) questionnaire; the Nursing Professional Identity Scale (NPIS); and the Compassion Fatigue-Short Scale (CF-Short Scale). ANOVA, Spearman correlation analysis, and multiple linear regression were performed to analyze the data. Results: The mean total behavioral intention score was 179.46 (± 14.83) out of a total score of 189.00, which represented a high level of intention toward caring for patients on mechanical ventilation. Multiple linear regression revealed that subjective norms (β = 0.390, P<0.001), perceived behavioral control (β = 0.149, P<0.001), professional identity (β = 0.101, P = 0.009), and compassion fatigue (β = 0.088 P = 0.024) were significant predictors of nurses' behavioral intention. Conclusions: Most nurses have a positive behavioral intention to care for COVID-19 patients undergoing mechanical ventilation. The findings in this study provide some insight for developing effective and tailored strategies to promote nurses' behavioral intention toward caring for ventilated patients under the pandemic situation. [ABSTRACT FROM AUTHOR]

High loadings of nitrate (NO3-) in the aerosol over China significantly exacerbate the air quality and pose a great threat to ecosystem safety through dry–wet deposition. Unfortunately, limited ground-level observation data make it challenging to fully reflect the spatial pattern of NO3- levels across China. Until now, long-term monthly particulate NO3- datasets at a high resolution were still missing, which restricted the assessment of human health and ecosystem safety. Therefore, a unique monthly NO3- dataset at 0.25 ∘ resolution over China during 2005–2015 was developed by assimilating surface observations, satellite products, meteorological data, land use types and other covariates using an ensemble model combining random forest (RF), gradient-boosting decision tree (GBDT), and extreme gradient-boosting (XGBoost) methods. The new developed product featured an excellent cross-validation R2 value (0.78) and relatively lower root-mean-square error (RMSE: 1.19 µgNm-3) and mean absolute error (MAE: 0.81 µgNm-3). Besides, the dataset also exhibited relatively robust performance at the spatial and temporal scales. Moreover, the dataset displayed good agreement with (R2=0.85 , RMSE=0.74 µgNm-3 , and MAE=0.55 µgNm-3) some unlearned data collected from previous studies. The spatiotemporal variations in the developed product were also shown. The estimated NO3- concentration showed the highest value in the North China Plain (NCP) (3.55±1.25 µgNm-3); followed by the Yangtze River Delta (YRD) (2.56±1.12 µgNm-3), Pearl River Delta (PRD) (1.68±0.81 µgNm-3), and Sichuan Basin (1.53±0.63 µgNm-3), and the lowest one in the Tibetan Plateau (0.42±0.25 µgNm-3). The higher ambient NO3- concentrations in the NCP, YRD, and PRD were closely linked to the dense anthropogenic emissions. Apart from the intensive human activities, poor terrain condition might be a key factor for the serious NO3- pollution in the Sichuan Basin. The lowest ambient NO3- concentration in the Tibetan Plateau was contributed by the scarce anthropogenic emission and favourable meteorological factors (e.g. high wind speed). In addition, the ambient NO3- concentration showed a marked increasing tendency of 0.10 µgNm-3yr-1 during 2005–2014 (p<0.05), while it decreased sharply from 2014 to 2015 at a rate of -0.40 µgNm-3yr-1 (p<0.05). The ambient NO3- levels in Beijing–Tianjin–Hebei (BTH), YRD, and PRD displayed gradual increases at a rate of 0.20, 0.11, and 0.05 µgNm-3yr-1 (p<0.05) during 2005–2013, respectively. The gradual increases in NO3- concentrations in these regions from 2005 to 2013 were due to the fact that the emission reduction measures during this period focused on the reduction of SO2 emission rather than NOx emission and the rapid increase in energy consumption. Afterwards, the government further strengthened these emission reduction measures and thus caused the dramatic decreases in NO3- concentrations in these regions from 2013 to 2015 (p<0.05). The long-term NO3- dataset over China could greatly deepen the knowledge about the impacts of emission reduction measures on air quality improvement. The monthly particulate NO3- levels over China during 2005–2015 are open access at 10.5281/zenodo.3988307 (Li et al., 2020c). [ABSTRACT FROM AUTHOR]

In response to the Strategic call for the "Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area, the Yangtze River Economic Belt is adjusting the agricultural industry structure, optimizing the input - output ratio, and ensuring stable and sustainable agricultural production. Based on the combination of the three-stage Data Envelopment Analysis (DEA) model and cluster analysis, this study examined the Yangtze River Economic Belt from 2008 to 2018 to measure its agricultural production efficiency and to analyze its temporal and spatial characteristics. Studies showed that exogenous environmental factors significantly (P <5%) impacted agricultural production efficiency in the Yangtze River Economic Zone, and there were temporal and spatial differences. These included; (T) after excluding environmental factors, the overall agricultural production efficiency of the Yangtze River Economic Zone had improved. Sichuan Province and Jiangsu Province were at the forefront of efficiency, whereas the agricultural production efficiency of Shanghai had declined obviously. (2) The agricultural production efficiency of the Yangtze River Economic Belt varied year by year, with fluctuating development. The middle reaches of the Yangtze River had advanced agricultural production efficiency more than the upstream and downstream regions, and the agricultural production efficiency of the individual provinces did not match their economic and social development. (3) Increases in labor, land, irrigation, and other input factors increased agriculture production efficiency, and there was no correlation between fiscal investment, per capita gross domestic product (GDP) and agricultural production efficiency, while the disaster-affected area had a significantly negative impact on agricultural production efficiency. [ABSTRACT FROM AUTHOR]

The typological and scientific analysis of bronze artefacts has been widely applied to the issue of local production versus important, which can be further linked to the long‐distance trade exchange and movement of raw materials, technology and people. Bronze artefacts bearing stylistic features of different regional origins have been discovered at the site of Moutuo in Sichuan, south‐west China. This study investigates the metal provenance of these artefacts by using the impurity patterns of the Oxford system. By combining the Pb isotopic data, it is feasible to distinguish the locally produced objects from those importations. This study contributes a detailed case study to the wider question of the movement of metal in south‐west China between the Late Bronze Age and Early Iron Age. [ABSTRACT FROM AUTHOR]

The Bayueshan (BYS) tunnels are adjacent tunnels which comprise key engineering structures important for Yurong highway from Chongqing to Sichuan, China. The tunnels were established crossing over the old goafs of a coal mine. The tunnels have been damaged three times between 2014 and 2016. To evaluate the reasons for the damage, fast Lagrangian analysis of continua in three dimensions ( FLAC 3 D ) was used to simulate the underground coal-mine excavation yearly from 2012 to 2015. The simulation results show that the subsidence of the ground surface increased annually. The maximum subsidence of the left tunnel was 505 mm and that of the right tunnel was 512 mm. The excavation led to increase in the tunnels' stress concentration. The simulations further show that uneven horizontal displacement and subsidence were the major factors in inducing tunnel construction defects. Poor geological conditions, water, and vehicle dynamic loads were also important factors that induced damage. Several engineering suggestions for ways to maintain the tunnels are given in this paper, and the research provides a reference for safety evaluation for tunnels crossing over an old goaf. [ABSTRACT FROM AUTHOR]

Background: Variations in human papillomavirus (HPV) E6 and E7 have been shown to be closely related to the persistence of the virus and the occurrence and development of cervical cancer. Long control region (LCR) of HPV has been shown multiple functions on regulating viral transcription. In recent years, there have been reports on E6/E7/LCR of HPV-16 and HPV-58, but there are few studies on HPV-52, especially for LCR. In this study, we focused on gene polymorphism of the HPV-52 E6/E7/LCR sequences, assessed the effects of variations on the immune recognition of viral E6 and E7 antigens, predicted the effect of LCR variations on transcription factor binding sites and provided more basic date for further study of E6/E7/LCR in Chengdu, China. Methods: LCR/E6/E7 of the HPV-52 were amplified and sequenced to do polymorphic and phylogenetic analysis. Sequences were aligned with the reference sequence by MEGA 7.0 to identify SNP. A neighbor-joining phylogenetic tree was constructed by MEGA 7.0, followed by the secondary structure prediction of the related proteins using PSIPRED 4.0. The selection pressure of E6 and E7 coding regions were estimated by Bayes empirical Bayes analysis of PAML 4.9. The HLA class-I and II binding peptides were predicted by the Immune Epitope Database server. The B cell epitopes were predicted by ABCpred server. Transcription factor binding sites in LCR were predicted by JASPAR database. Results: 50 SNP sites (6 in E6, 10 in E7, 34 in LCR) were found. From the most variable to the least variable, the nucleotide variations were LCR > E7 > E6. Two deletions were found between the nucleotide sites 7387–7391 (TTATG) and 7698–7700 (CTT) in all samples. A deletion was found between the nucleotide sites 7287–7288 (TG) in 97.56% (40/41) of the samples. The combinations of all the SNP sites and deletions resulted in 12 unique sequences. As shown in the neighbor-joining phylogenetic tree, except for one belonging to sub-lineage C2, others sequences clustered into sub-lineage B2. No positive selection was observed in E6 and E7. 8 non-synonymous amino acid substitutions (including E3Q and K93R in the E6, and T37I, S52D, Y59D, H61Y, D64N and L99R in the E7) were potential affecting multiple putative epitopes for both CD4+ and CD8+ T-cells and B-cells. A7168G was the most variable site (100%) and the binding sites for transcription factor VAX1 in LCR. In addition, the prediction results showed that LCR had the high probability binding sites for transcription factors SOX9, FOS, RAX, HOXA5, VAX1 and SRY. Conclusion: This study provides basic data for understanding the relation among E6/E7/LCR mutations, lineages and carcinogenesis. Furthermore, it provides an insight into the intrinsic geographical relatedness and biological differences of the HPV-52 variants, and contributes to further research on the HPV-52 therapeutic vaccine development. [ABSTRACT FROM AUTHOR]

In recent years, a series of earthquakes have occurred in Sichuan province, southwest China. On April 20, 2013, 1013 landslides were triggered in the Lushan earthquake within the research area of 1215.87 km2. On August 8, 2017, 821 landslides were induced in the Jiuzhaigou earthquake within the study area of 541.61 km2. The slope, aspect, elevation, distance to the river, distance to fault, stratum lithology, curvature, and PGA as evaluation factors were chosen to research the distribution characteristics of coseismic landslides. The relationship between influence factors and distribution of coseismic landslides were analyzed using landslide area density (LAD), defined as the ratio between the coseismic landslides area and the total area under the specific classification of eight factors, and landslide number density (LND), interpreted as the number of landslides per square kilometer affected by an earthquake. Both the LAD and LND curves show the common correlations between distribution characteristics of coseismic landslides and the classification of eight factors. The high density of coseismic landslides was found at locations where the valley evolves from U-shaped to V-shaped, along slopes with an inclination between 20 and 50°. Due to the effect of river cutting erosion and human engineering activities, massive coseismic landslides appeared within the scope of 200 m from the river system. Eight hundred sixty small shallow coseismic landslides were found less than 3 km from the seismogenic fault in both earthquakes. Both concave and convex terrain has the same effect of promoting coseismic landslides. The strata of the Carboniferous and Cretaceous are more prone to coseismic landslides occurrence. In the event of another earthquake of similar magnitude in southwest China in the future, the research results can quickly predict the distribution of coseismic landslides and provide a scientific basis for emergency rescue. [ABSTRACT FROM AUTHOR]

Under the background of China getting old before getting rich, the elderly service, as a public project, should be coordinated with the degree of aging and economic level to avoid the improper allocation of public resources. This article aims to investigate whether an insufficient or overthreshold phenomenon exists in China. Firstly, based on the "active aging theory," the elderly service index is constructed, and then matching and coordination models are proposed to obtain coordination degrees among aging, the elderly service, and the economy. In terms of coordination, elderly service-aging is at a low level and elderly service-economic level shows an agglomeration of high in the east and low in the west, while the elderly service-aging-economic level is quite different among provinces. In provinces with high coordination (e.g., Beijing and Guangdong), the elderly services are appropriate. In comparison, in provinces with low coordination, the elderly services may either lag behind the aging degree (e.g., Sichuan) or exceed the local economic level (e.g., Shannxi). Therefore, the development of aging services should focus on coordination rather than quantification and scale. Considering the regional heterogeneity, we can formulate soft constraints allowing a lower minimum limit and greater flexibility range. [ABSTRACT FROM AUTHOR]