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This article discusses a landslide that occurred on the G213 National Highway in Songpan County, Sichuan, China. The landslide, which was triggered by heavy rainfall, led to the closure of the highway for almost 50 days and caused damage to infrastructure. The article provides a detailed analysis of the landslide, including information about the geological setting, climate conditions, and morphology. The study emphasizes the importance of long-term monitoring and disaster prevention measures in landslide-prone areas and provides data that can be used for further research and awareness. [Extracted from the article]

The natural gas resources in the Sichuan Basin are abundant and exhibit various phenomena, for example, mixed sources, mixed maturities and overlapping combinations, resulting in great difficulties in identifying natural gas sources. In this study, several groups of thermal simulation experiments were conducted on various types of kerogens using closed and/or semi‐open systems to investigate the characteristics of the carbon isotope compositions of light hydrocarbon gases derived from different typical kerogens. The results showed that the carbon isotope compositions and variation trends of methane and ethane are controlled by the kerogen type, thermal simulation system and thermal evolution degree. The carbon isotope compositions of light hydrocarbon gases derived from different types of kerogens exhibit some differences with increased thermal evolution degree. When the thermal simulation temperature increases from 320 to 550°C, the methane carbon isotope of typically marine source rocks, mainly type I and type II1 kerogens, is slightly higher than or equivalent to that of ethane. However, the ethane carbon isotope of terrestrial source rocks, primarily types II2 and III kerogens, is significantly heavier than methane. By comparison, the evolution trend of carbon isotope compositions of actual natural gas is well consistent with that of light hydrocarbon gases cracked from thermal simulation experiments with increased thermal evolution degree. These findings are of great importance to identify the source rock of actual natural gas with high thermal maturities, as well as to determine the sources of deep shale gas in the southern Sichuan Basin, the Yuanba gas field and the Puguang gas field. Finally, a fitting method of carbon isotope values of methane and ethane of light hydrocarbon gases can be used to more finely differentiate the sources of natural gas in complex areas with mixed sources, mixed maturities and overlapping combinations. [ABSTRACT FROM AUTHOR]

Simple Summary: The intestinal microbiome structure and diversity of Alpine musk deer in Gansu (origin) and Sichuan (migration) were analyzed in this study using 16S rRNA high-throughput sequencing technology. The study revealed that there were no alterations in the dominant intestinal species between musk deer in the origin and migration areas. However, there were significant differences in their relative abundance. Therefore, specific measures should be implemented for the feeding and management of migratory Alpine musk deer. This study provides a theoretical foundation for expanding artificial populations and reintroducing wild populations. In China, the population of wild musk deer, belonging to the family Moschidae, has drastically decreased in recent years owing to human activities and environmental changes. During the 1990s, artificial breeding of Alpine musk deer was conducted in Xinglong Mountain, Gansu Province, China, and their ex situ conservation was explored for over a decade. Ex situ protection is beneficial for expanding the population of animals and maintaining their genetic diversity; however, it can also induce metabolic diseases and parasitic infections and reduce reproductive capacity. The gut microbiota of animals has a considerable impact on host energy metabolism and immune regulation, thereby playing a crucial role in the overall health and reproductive success of the host. In this study, by comparing the differences in the intestinal microbiome of the musk deer according to their place of origin and migration, the changes in their gut microbiota and the influencing factors were explored to provide a theoretical basis for monitoring the health status of the musk deer. We used 16S rRNA high-throughput sequencing technology to analyze the structure and diversity of the gut microbiota of Alpine musk deer in Gansu (G, place of origin) and Sichuan (S, place of migration). The results showed that the dominant bacteria and genera in the intestinal microbiome of captive musk deer were similar in the places of origin and migration, but significant differences were observed in their relative abundance (p < 0.05). Regarding Firmicutes and Actinobacteria, which are related to plant cellulose digestion, the relative abundance in group G was higher than that in group S; regarding Proteobacteria and Verrucomicrobia, which are related to fat and starch intake, the relative abundance in group S was higher than that in group G; the relative abundance of Bacillus and Clostridium sensu stricto, which are related to fiber digestibility, was higher in group G than in group S; the relative abundance of conditional pathogens Acinetobacter and Escherichia–Shigella was higher in group S than in group G. The results of α and β diversity analysis also showed significant differences between the two groups (p < 0.05). The ACE and Shannon indices of musk deer in group G were considerably higher than those in group S, and the Simpson index of musk deer in group S was greater than that in group G, indicating that the abundance and diversity of intestinal microbiome were higher in musk deer of Gansu than those of Sichuan. Comparison of the changes in the intestinal microbiome of the musk deer according to the place of origin and migration showed that the plant cellulose content in the food of the musk deer, the fat content in the concentrated feed, and changes in the feeding environment have an impact on the intestinal microbiome. Effective monitoring of the health and immunity of the musk deer is crucial for ensuring their overall health, which in turn will aid in formulating a scientific and reasonable management plan for their conservation. [ABSTRACT FROM AUTHOR]

The location of Low-Altitude Flight Service Station (LAFSS) is a comprehensive decision work, and it is also a multi-objective optimization problem (MOOP) with constraints. As a swarm intelligence search algorithm for solving constrained MOOP, the Immune Algorithm (IA) retains the excellent characteristics of genetic algorithm. Using some characteristic information or knowledge of the problem selectively and purposefully, the degradation phenomenon in the optimization process can be suppressed and the global optimum can be achieved. However, due to the large range involved in the low-altitude transition flight, the geographical characteristics, economic level and service requirements among the candidate stations in the corridor are quite different, and the operational safety and service efficiency are interrelated and conflict with each other. And all objectives cannot be optimal. Therefore, this article proposes a Modified Immune Algorithm (MIA) with two-layer response to solve the constrained multi-objective location mathematical model of LAFSS. The first layer uses the demand track as the cell membrane positioning pattern recognition service response distance to trigger the innate immunity to achieve the basic requirements of security service coverage. In the second layer, the expansion and upgrading of adjacent candidate sites are compared to the pathogen's effector, and the adaptive immunity is directly or indirectly triggered again through the cloning, mutation and reproduction between candidate sites to realize the multiobjective equilibrium of the scheme. Taking 486,000 km2 of Sichuan Province as an example, MIA for LAFSS is simulated by the MATLAB platform. Based on the Spring open source application framework of Java platform, the cesiumjs map data is called through easyui, and the visualization of site selection scheme is presented with the terrain data of Map World as the background. The experimental results show that, compared with dynamic programming and ordinary immunization, the immune trigger mode of double response and the improved algorithm of operation parameter combination designed by the Taguchi experiment, the total economic cost of location selection is reduced by 26.4%, the service response time is reduced by 25%, the repeat coverage rate is reduced by 29.5% and the effective service area is increased by 17.5%. The security risk, service efficiency and location cost are balanced. The present work is to provide an effective location method for the layout number and location of local transfer flight service stations. For complex scenes with larger scale of low-altitude flight supply and demand and larger terrain changes in the region, the above research methods can be used to effectively split and reduce the dimension. [ABSTRACT FROM AUTHOR]

This article investigates the history of midwifery from the 1920s to 1940s in China through looking at the linkage between modern midwifery and maternal mortality in urban areas. It first shows that people's perceptions of maternal mortality and its causes changed from the nineteenth to the twentieth century, and that a modern form of midwifery service took shape in the Republican era (1912–49) in order for reducing maternal mortality rate and building a strong nation. Evidence from urban areas of Beijing and Sichuan between the 1920s and the 1940s demonstrates that the practice of modern midwifery varied with medical infrastructure and personnel in different places, and that modern midwives in small towns may practise against the rules, taking the initiative to use forceps and perform surgery to save mothers' lives. The relationship between modern midwifery and maternal mortality in the researched period was more complex than medical experts' anticipation. [ABSTRACT FROM AUTHOR]

Background: Heart failure (HF) is a major complication following ischemic heart disease (IHD) and it adversely affects the outcome. Early prediction of HF risk in patients with IHD is beneficial for timely intervention and for reducing disease burden. Methods: Two cohorts, cases for patients first diagnosed with IHD and then with HF (N = 11,862) and control IHD patients without HF (N = 25,652), were established from the hospital discharge records in Sichuan, China during 2015-2019. Directed personal disease network (PDN) was constructed for each patient, and then these PDNs were merged to generate the baseline disease network (BDN) for the two cohorts, respectively, which identifies the health trajectories of patients and the complex progression patterns. The differences between the BDNs of the two cohort was represented as disease-specific network (DSN). Three novel network features were exacted from PDN and DSN to represent the similarity of disease patterns and specificity trends from IHD to HF. A stacking-based ensemble model DXLR was proposed to predict HF risk in IHD patients using the novel network features and basic demographic features (i.e., age and sex). The Shapley Addictive exPlanations method was applied to analyze the feature importance of the DXLR model. Results: Compared with the six traditional machine learning models, our DXLR model exhibited the highest AUC (0.934 ± 0.004), accuracy (0.857 ± 0.007), precision (0.723 ± 0.014), recall (0.892 ± 0.012) and F1 score (0.798 ± 0.010). The feature importance showed that the novel network features ranked as the top three features, playing a notable role in predicting HF risk of IHD patient. The feature comparison experiment also indicated that our novel network features were superior to those proposed by the state-of-the-art study in improving the performance of the prediction model, with an increase in AUC by 19.9%, in accuracy by 18.7%, in precision by 30.7%, in recall by 37.4%, and in F1 score by 33.7%. Conclusions: Our proposed approach that combines network analytics and ensemble learning effectively predicts HF risk in patients with IHD. This highlights the potential value of network-based machine learning in disease risk prediction field using administrative data. [ABSTRACT FROM AUTHOR]

Land surface albedo (LSA) is an important parameter in surface energy balance and global climate change. It has been used in the fields of energy budgets, climate dynamics, and land surface processes. To apply satellite LSA products more widely, the product accuracy needs to be evaluated at different scales and under atmospheric and surface conditions. This study validates and analyzes the errors of the LSA datasets from the Global LAnd Surface Satellites (GLASS) product, the European Space Agency's Earth Observation Envelope Programme (GlobAlbedo), the Quality Assurance for Essential Climate Variables (QA4ECV) project, the Gap-filled Snow-free Bidirectional Reflectance Distribution Function (BRDF) parameters product (MCD43GF), and the Satellite Application Facility on Climate Monitoring (CM SAF) Albedo dataset from the AVHRR data (CLARA-SAL) against the Chinese Ecosystem Research Network (CERN) measurements at different spatiotemporal scales over China from 2005 to 2015. The results show that LSA estimated by GLASS agrees well with the CERN measurements on a continental scale. The GLASS product is characterized by a correlation coefficient of 0.80, a root-mean-square error of 0.09, and a mean absolute error of 0.06. The consistency between GLASS, GlobAlbedo, and CLARA-SAL is slightly lower over the regions with high aerosol optical depth (AOD) (e.g. Sichuan Basin, northern China) and high cloud cover compared with that in regions with lower AOD and low cloud cover. The estimation errors are related to varying atmospheric and surface conditions and increase with increasing AOD and cloud cover and decreasing enhanced vegetation index. Therefore, algorithms under complex atmospheric and surface conditions (e.g. high AOD, sparse vegetation) should be optimized to improve the accuracy of LSA products. [ABSTRACT FROM AUTHOR]

Organic matter pores (OMP) provide significant storage space for hydrocarbons in lower Silurian Longmaxi shales in the Dingshan field of southern Sichuan, China. The distributions of organic matter and the different OMP structure parameters were characterized through Ar-ion polishing, scanning electron microscopy (SEM), and image analysis software for shale samples of different wells. The research results indicated that organic matter has been divided into two categories based on its occurrence, location, and its relationship with authigenic minerals: organic matter in situ and migrated organic matter. OMP for organic matter in situ are mainly micropores mostly arranged isolatedly, while in migrated organic matter pores show larger sizes and higher roundness. The development of OMP in samples is predominantly controlled by the formation pressure. The existence of overpressure alleviated the stress on the rock skeleton, causing the compaction of some migrated organic matters to lag or decrease. This played a positive role in protecting the development of pores in the interior and edge of the rock skeleton, and it can also induce the development of microfractures in shale. The protective effect of formation pressure on organic pores was provided for understanding the exploration and exploitation of Longmaxi shales in the study area. [ABSTRACT FROM AUTHOR]

Due to high oil content and complex composition, Kitchen waste (KW) is refractory for biotreatment and easily causes environmental burden, especially in Sichuan area with greasy cooking habits. To facilitate KW composting, a nitrogen-retaining & decomposing-promoting microbial agent (NRDPMA) was constituted with functional bacteria to decompose refractory substances, retain nutrients, and reduce gas emission. With NRDPMA, high-temperature period was achieved 2 days earlier and extended by 6 days, shorting the process by 15 days. 36.57% less NH 3 and 22.30% less H 2 S were released. The total nitrogen of the compost product was increased by 17.14%. Functional bacteria in NRDPMA (e. g. Bacillus , Pseudomonas , and Oceanobacillus) displayed obvious advantages throughout composting, which reshaped microbial community composition and drove material transformation. PICRUST2 prediction confirmed a higher gene occurrence related to metabolism of lipid, lignocellulose, and nitrogen. The great decomposing and transformation capacity made NRDPMA an alternative to improve the efficiency of composting on recycling such lipid-containing waste. And functional bacteria targeting refractory components should be included for biotreatment of waste. This study should give a new perspective on industrial KW composting. [Display omitted] • 6 days longer high-temperature period with 36.57% less NH 3 and 22.30% less H 2 S. • NRDPMA conserved 17.14% higher nitrogen with 15 days shorter composting period. • Functional bacteria of NRDPMA targeting lipid, starch, and cellulose played a crucial role. • NRDPMA participated in all the composting periods, drove microbial community change. [ABSTRACT FROM AUTHOR]

Abstract: Based on well correlation, division of sedimentary facies and microfacies, core observation, and analysis of rock thin sections, the authors comparatively analyzed the sedimentation and diagenesis of the oolitic beaches in the Puguang and Yuanba areas of northeastern Sichuan Basin, and expounded their control on reservoirs. In the Puguang area the oolitic beach is thick and lateral migration distance is short, intervals overlaid one another, while in the Yuanba area the oolitic beach is thin and lateral migration distance is long. The two areas both experienced various types of diagenesis. There happened intense early dissolution and wide-spread dolomitization in the oolitic beach of the Puguang area, where type-I reservoirs of high porosity and permeability are developed. In the Yuanba area, strong compaction and pressure dissolution, and late burial cementation led to the development of type-III reservoirs of low porosity and permeability. The main factors that control the sedimentation and diagenesis are paleotopography and changes in sea level. Sedimentation controls the distribution and thickness of reservoir, and diagenesis determines the porosity formation and evolution and ultimately the reservoir quality. [Copyright &y& Elsevier]

[Display omitted] • Evolution of asphaltene-adsorbed aromatics is retarded compared to free ones. • Asphaltene-occluded aromatics profiles respond insignificantly to thermal stress. • Distributions of occluded aromatics are probably thermodynamically controlled. • Steric hindrance imposes a kinetic barrier on the reaction of trapped molecules. The thermal evolution of components trapped in matrix of asphaltenes is supposed to be retarded, as compared to the free ones. Studying the geochemical evolution of trapped polycyclic aromatic hydrocarbons (PAHs) may provide insight for the characterization of high-maturity organic matter. The discrepancies in the thermal evolution between free and trapped (asphaltene-adsorbed/occluded) PAHs (phenanthrene, chrysene, pyrene, and their methylated isomers) were studied by thermal maturation (gold tubes, 300 ∼ 400 °C) experiments on a low-maturity solid bitumen from the Sichuan Basin, southwestern China. The results show that the thermal evolution of asphaltene-adsorbed PAHs is retarded compared to that of free ones. This is attributed to slight differences in reaction kinetics due to steric hindrance by the asphaltene structure. The asphaltene matrix appears to act as a reaction inhibitor leading to a retardation of the thermal evolution of the methylphenanthrene index (MPI) in asphaltene-adsorbed hydrocarbons. This could provide a possibility for maturity assessment of high-maturity organic matter. The thermal evolution of asphaltene-occluded PAHs in the experiments resulted in thermodynamically controlled isomer distributions of occluded methylphenanthrenes and methylchrysenes. However, the occluded methylpyrene isomers were hardly affected by thermal stress. They probably retained their original distributions and may serve as source indicators. [ABSTRACT FROM AUTHOR]

• Thermal evolution of biomarkers trapped by asphaltene structure is distinctly delayed compared with that of free biomarkers. • The potential chemical conversion between asphaltene-occluded n -alkanes and n -alkenes may be related to the different metastable equilibrium of the system. • Steranes and terpanes occluded by asphaltenes can preserve the original characteristics of the diagenesis stage during thermal maturation. • The occlusion space formed by asphaltene aggregates presumably restricts the transformation of active biomarkers during the thermal evolution. Asphaltene-trapped (adsorbed or occluded) biomarkers are considered a valid source of information for crude oil with severe secondary alterations. However, thermal stress might change asphaltene-trapped hydrocarbons to some extent. Therefore, it is indispensable to investigate the thermal evolution behavior of asphaltene-trapped biomarkers. In this study, low-maturity bitumen from the Kuangshanliang area of the Sichuan Basin (China) was selected as a sample. The thermal evolution behavior of free and asphaltene-trapped saturated biomarkers was investigated by thermal simulation experiments. The results revealed, in addition to normal biomarkers, also a series of even carbon number n -alk-(1)-enes in asphaltene-occluded hydrocarbons. All of them were hardly influenced by secondary alterations. Moreover, due to the restriction of macromolecular structure, the thermal evolution of asphaltene-trapped biomarkers lags behind that of free biomarkers. Most biomarker parameters of occluded hydrocarbons changed little with increasing maturity. In particular, the distributions of occluded terpanes or steranes retained the characteristics of early diagenesis of organic matter, even if they suffered from strong thermal alteration. [ABSTRACT FROM AUTHOR]