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On December 4, 2020, a massive high-locality landslide occurred at Qingliu Village, Li County, Sichuan Province, China (UTC + 8). This event resulted in a landslide deposit of approximately 34.8 × 104 m3, causing the destruction of two roads and several houses on the hillslope and blocking a downstream river. Extensive field investigations, UAV photography, borehole drilling, and GNSS monitoring were conducted after the landslide. Additionally, a PFC3D numerical simulation was used to reproduce the movement of the landslide after calibrating its meso-strength parameters. Based on the motion and deposit characteristics, the landslide is divided into a major sliding zone (comprising the source zone, impact-shoveling zone, and deposition zone) and a landslide-affected zone. The primary triggering factor for the Qingliu landslide is the slope mass damage caused by frequent preceding earthquakes. On the other side, the direct triggers are continuous rainfall and upslope meltwater, which increased the weight and further weakened the strength of the slope mass. The landslide initiation involves the formation of a tensile crack in the major sliding zones, followed by the shoveling of loose debris by the displaced landslide mass, and then termination with the striking at the slope foot and damming a river. This study offers valuable insights into the evolutionary processes of high-locality landslides. [ABSTRACT FROM AUTHOR]

Feldspar alteration is among the most important processes in clastic rocks during diagenesis, but uncertainty remains about the factors that control feldspar diagenesis under subsurface conditions. Hence, the Upper Triassic Xujiahe formation of the Western Sichuan Basin were examined by an integrated petrographic, mineralogical and geochemical approach to unravel the causes and effects of feldspar diagenesis, with implication for mass transfer and openness of the geochemical system. The sandstones at various depths demonstrate three distinct, separate diagenetic behaviors of detrital feldspar within a single formation including (1) the complete dissolution of both plagioclase and K-feldspar in the upper member; (2) conservation of abundant detrital feldspar grains with minor albitization or overgrowths within the lower member of depths greater than 5 km; and (3) complete disappearance of K-feldspar within the uppermost horizons of the lower member, while plagioclase have survived in significant amounts. The exceptional disappearance of K-feldspar is the result of selective dissolution of K-feldspar during burial, accompanied by illite cementation and substantial K transfer at a scale of tens of meters. It is apparent that the clay diagenesis in the overlying mudstones, rather than porewater chemistry, is the major control of the reactivity of K-feldspar in adjacent deeply buried sandstones. [ABSTRACT FROM AUTHOR]

Background: Few studies on molecular epidemiology have studied people with newly diagnosed HIV infection and ART Failure Patients at the same time in rural China. With more serious HIV epidemic than in other provinces in China, Sichuan is an area suitable for this study. Objective: To analyze the characteristics of HIV-1 molecular networks and factors related to network entry among newly diagnosed HIV infection and ART Failure Patients in three county-level cities (A, B, C) in Sichuan Province, to provide scientific basis for accurate prevention and control. Methods: Nested PCR amplification method was used to amplify HIV-1 pol gene region of 530 blood samples, Sequencer 4.9 was used to edit, clean and splice the gene sequence, Bioedit correction, Fastree 2.1.8 and Figtree 1.4.2 to construct evolutionary tree and determine genotype. HyPhy2.2.4 and Cytoscape 3.6.1 software were used to construct molecular network. Logistic regression analysis was applied. Results: 523(98.68%) pol sequences were obtained, and a total of 518 valid sequences with basic information came into the final analyses. A total of 6 genotypes were detected, namely CRF01_AE (320,61.78%), CRF07_BC (149,28.76%), B (30,5.79%), CRF08_BC (11, 2.12%), CRF55_01B (6, 1.16%) and C (2, 0.39%). 186 of 518(35.91%) sequences entered the network at a genetic distance of 0.8%, forming 42 propagation clusters. "High-risk transmitters"(connected with two and more) accounted for 21.62%. Logistic regression showed that≥50 years old (OR = 2.474) were more risky than 18–49 years old, CRF07_BC sub-type (OR = 0.174) were less risky than CRF01_AE sub-type, B sub-type (OR = 6.698) is higher risky than CRF01_AE sub-type, and District B (OR = 0.077) less risky than that of A city. Conclusion: The sources of HIV infection in rural Sichuan are diversified and complicated. The prevention and control of HIV infection in Sichuan Province should focus on strengthening the long-term dynamic detection of elderly population, B strain sub-type, and in City A. [ABSTRACT FROM AUTHOR]

A new Chinese ant species Carebara laeviceps sp. nov. is described based on the major and minor workers. This species is most similar to C. lusciosa (Wheeler, 1928) due to a spineless propodeum, the absence of horns, and a smooth head capsule. It is distinguished by the following features: (1) antenna 10-segmented; (2) katepisternum rugose-reticulate; (3) in major workers, lateral sides of head in full-face view parallel; (4) metanotal groove distinct, anterodorsal corner forming an acute tooth behind metanotal groove. Moreover, an updated key to Chinese Carebara species is presented based on major workers, with a checklist comprising a total of 36 Chinese Carebara species and subspecies. Morphological structures and scanning electron micrographs of the newly discovered species’ minor and major workers are provided. [ABSTRACT FROM AUTHOR]

Melanoseris kangdingensis, a new species native to western Sichuan, China, is firstly described and illustrated, and its conservation status is also assessed. It bears resemblance to M. macrantha and M. bracteata in terms of morphology; however, there are distinguishing characteristics in terms of their leaf structure, presence of bracts, hairiness of involucre, number of florets, and length of both stamen tube and achene’s beak. [ABSTRACT FROM AUTHOR]

The security of natural gas supply and demand has always been an important topic, and as a result, analyzing and predicting the supply and demand of natural gas has received considerable attention from researchers. Numerous studies have extensively researched the supply and demand of natural gas. The main purpose of this study is to explore the supply‐demand balance mechanism for natural gas security. A system dynamics model is constructed to assess the supply and demand of natural gas in Sichuan Province, China. A new system dynamics model based on domestic gas, production gas, ecological environment and natural gas supply is proposed. The study considers four scenarios: natural development, economic priority development, environmental priority development and coordinated development. The results show that the rapid economic development has led to an excessive environmental carrying capacity, a larger gap between natural gas supply and demand, a decline in the quality of life of residents, and even affected the energy security of Sichuan Province and China. The findings also show that people's overprotection of the environment can lead to slow economic development, which prevents it from achieving its desired goals. The coordinated development scenario in this paper not only ensures the production of natural gas and the quality of life of residents, but also is an optimal scheme with low energy consumption and pollution. According to the research conclusions, considering the overall situation of China's energy security and the situation in Sichuan Province, the author proposes reforms from the supply and demand sides of natural gas. [ABSTRACT FROM AUTHOR]

The rural centralized residence (RCR), a policy that guides rural households to reside in centralized residential communities or central villages, has been widely implemented in China and other developing countries to promote rural development. RCR can effectively improve local public facilities and stimulate more local business opportunities, thus affecting the migration decisions of rural household members. Using a large household‐level survey data set from Sichuan province, China, we estimated the causal effects of RCR on rural labor migration via the instrumental variable approach while controlling for the within‐town contiguous‐villages group fixed effects. We found that on average the proportion of household members that are migrant workers decreases by 17.2 percentage points if households choose to embrace RCR. Additional analyses on the mechanisms indicate that RCR increases local employment opportunities, decreases search and transportation expenses for local jobs, and leads to increased satisfaction with local supporting facilities. [ABSTRACT FROM AUTHOR]

Few studies have tested the influence of climatic factors on yields by adjusting sowing dates at both low and high altitudes. We investigated the influence of the synergistic effects of temperature and solar radiation by conducting field experiments using different rice varieties and sowing dates in the low-altitude plains of Chongzhou and the high-altitude mountainous region of Hanyuan, Sichuan Province, China, in 2017 and 2018. The results showed that from transplanting to maturity, biomass yield and grain yield were significantly (p < 0.01) correlated with the average daily temperature and solar radiation. The Hanyuan site experienced higher solar radiation and lower temperature than those of Chongzhou, which contributed to higher dry matter accumulation (DMA) and crop growth rate values pre- and post-anthesis and more panicles per m2, leading to higher biomass yields and grain yields at Hanyuan. The rice sowed earlier was subjected to higher solar radiation and lower temperature at Chongzhou and Hanyuan, resulting in increased DMA post-anthesis, panicles per m2, and spikelet filling, improving biomass yield and grain yield. These results indicate that the high potential yield from the early sowing date in the high-altitude region was primarily due to increased solar radiation and decreased temperatures. [ABSTRACT FROM AUTHOR]

The Sichuan Basin, located on the eastern margin of the Tibetan Plateau, is an intracontinental basin that developed in the Yangtze Block. The Cambrian–Silurian strata in this basin have enormous exploration potential in terms of natural gas, but their structural evolution during the Cambrian–Silurian remains controversial. Based on wells, seismic profiles, aeromagnetic data, and previous research results, this study investigated the structures related to the Leshan–Longnvsi palaeo‐uplift and the activity of the Cambrian–Silurian basement faults, revealing the activity of the extensional process during the Cambrian–Silurian. The results of this study were as follows: (1) the flattening of the bottom of the Permian strata in seismic profiles located in the Leshan–Longnvsi palaeo‐uplift revealed a large number of normal faults, grabens, and horsts in the Cambrian–Silurian strata, indicating that the Leshan–Longnvsi palaeo‐uplift was an extensional structure during the Cambrian–Silurian period; (2) balanced cross‐sections and strata isopach maps showed that all seven basement faults in the basin were normal faults during the Cambrian–Silurian; (3) Sichuan Basin was in an extensional setting during the Cambrian–Silurian; (4) seven basement faults controlled the extensional process during the Cambrian–Silurian in the Sichuan Basin. [ABSTRACT FROM AUTHOR]

• GNSS and GRACE/GFO are jointly inverted without any external a priori constraints. • Joint inverted TWS changes can better quantify extreme drought and flood in SCP. • Drought propagation time shows an increasing trend from southwest to northeast SCP. • Drought and flood recovery time in western SCP is relatively long during 2020–2022. The Global Navigation Satellite System (GNSS) surface deformation measurement and Gravity Recovery and Climate Experiment (GRACE)/GRACE Follow-on (GFO) satellite gravimetry provide complementary strengths in estimating terrestrial water storage (TWS) changes, which helps quantify the evolutions of extreme floods and droughts. We implemented a joint inversion framework that only incorporates the contributions of GNSS and GRACE/GFO to recover the TWS changes for monitoring extreme floods and droughts in the Sichuan Province of China (SCP). The performance of TWS changes from the joint inversion is evaluated through closed-loop simulation and independent hydrometeorological data (i.e., precipitation (P), evapotranspiration (ET), and runoff (R)) based on the water balance equation (named P-ET-R) in the spatio-temporal domains. The simulation analysis results show that joint inversion presents better performance in recovering TWS changes than GNSS-only and GRACE/GFO-only solutions in the spatio-temporal scales. The measured joint inversion results reveal more spatial details of TWS changes than GNSS-only and GRACE/GFO-only solutions and present better correlations with GLDAS- and ERA5-derived P-ET-R (0.77 vs. 0.79) than GNSS-only (0.49 vs. 0.54) and GRACE/GFO-only (0.61 vs. 0.68) in the spatial domain. Meanwhile, the joint inversion results effectively characterize the spatio-temporal dynamics of extreme floods and droughts in SCP during 2020–2022, the average TWS surpluses are 33.61 and 32.86 mm in 2020 and 2022 flood events and the average TWS deficits are −36.78 and −63.87 mm in 2021 and 2022 drought events. In addition, the drought propagation time generally presents an increasing trend from southwestern to northeastern SCP. Furthermore, the average and minimum recovery time of drought and flood in the Sichuan basin is longer than those in the western mountains during 2020–2022. The proposed approach provides an effective estimation strategy for recovering reliable TWS changes for the investigation of extreme floods and droughts in regions where GNSS stations are distributed. [ABSTRACT FROM AUTHOR]

• Alveolar echinococcosis has caused severe morbidity and mortality in endemic areas. • Prevention of the disease is challenging on the Qinghai-Tibet Plateau in China. • A control program of deworming owned dogs was implemented in Tibetan communities. • Human prevalence was reduced but there was no impact on the prevalence in intermediate hosts. Human alveolar echinococcosis (AE) is considered a neglected zoonotic disease by the World Health Organization (WHO). The causative pathogen, Echinococcus multilocularis , lives as an adult tapeworm in the intestinal tract of canines. AE was identified as an emerging public health issue in Tibetan communities of Shiqu County 20 years ago. On St. Lawrence Island, Alaska (USA), in the 1980s peri-domestic transmission of E. multilocularis was controlled by regular deworming of owned dogs over a 10-year period. In Tibetan communities, on the Tibetan Plateau, control of E. multilocularis transmission is challenging due to the continental setting, complex epidemiology, disease ecology, geography, and socio-cultural factors. However, a control programme based on deworming owned dogs using praziquental (PZQ) has been carried out since 2006. Assessment was conducted in townships where baseline data were available 10 years prior. Purging of dogs by oral administration of arecoline was used to measure E. multilocularis prevalence, trapping small mammals around communities was employed to assess the change in infection of pikas and voles, and analysis of human AE abdominal ultrasound-based data was used to understand the change in prevalence in the past decade. In all three evaluated townships, the E. multilocularis prevalence in owned dogs was significantly (P < 0.01) reduced from 7.23% (25/346) during 2000–2003 to 0.55% (1/181) in 2016. Human AE ultrasound-based prevalence (adjusted for age and sex) in five evaluated townships decreased significantly (P < 0.01) from 6.25% (200/3,198) during 2000–2002 to 3.67% (706/19,247) during 2015–2017. The 2016 prevalence of E. multilocularis metacestodes in small mammal intermediate hosts was not significantly different from the prevalence in 2008. The control programme was effective in reducing E. multilocularis infection in owned dogs and human AE prevalence, but did not significantly impact infection in wildlife intermediate hosts. [ABSTRACT FROM AUTHOR]

Unusual sedimentary deposits such as stromatolites, thrombolites, dendrolites, and giant ooids are widely distributed in the Permian–Triassic boundary (PTB) successions of shallow platform facies worldwide. These microbial fabrics, however, are rarely present in the same section. The genesis of these PTB microbialites and the oceanographic conditions linking to the end-Permian mass extinction still remain disputed despite intense study. Here, we report a stromatolite-dendrolite-thrombolite-giant ooid association from the PTB beds of the Yudongzi section on the northwestern margin of the Yangtze Platform, South China, which was situated in low latitudes during the Permian-Triassic (P-Tr) transition. The Yudongzi microbialites rest on an irregular contact with underlying Permian bioclastic limestone and are comprised of lower bedded stromatolite, digitate dendrolite, upper bedded stromatolite, and thrombolite units. The bedded stromatolite is characterized by undulating laminated structures and various amalgamated and layered clots. The digitate dendrolite is made up of digitate-like branches, formed by clots distributed in an arched arrangement, and characterized by abundant branching dendroids. The thrombolite displays distinct clotted textures that comprise a mixture of dark-colored microbial fabric and light-colored interstitial sediment. In microbialite, columnar structures identified as Gakhumella -like calcimicrobe are very abundant. Each individual of Gakhumella -like structure has densely arranged segments forming a columnar- to fan-shaped micro-structure. Single segments are arch-shaped and form a thin chamber between segments. Coccoid-like, bacterial clump-like, and other spheroidal aggregates are also commonly present and suggestive of a biogenetic origin for the Yudongzi microbialites. Moreover, distinct aragonite crystal fans are also for the first time found in the PTB microbialites in South China, suggesting that the fans may have resulted from high inorganic carbon concentrations, and thus high levels of carbonate dioxide in the seawater. The Yudongzi microbialites are capped by shelly grainstone and a massive giant oolite, implying that the demise of the Yudongzi microbialites may be due to destruction by strong wave currents in a high energy setting. Some ooids are coated unevenly by micritic laminae (or envelopes) indicating the possibility of a microbe-related origin. These microbial-coated giant ooids, together with the massive microbialites, may imply the long-term of microbial bloom in the oceans immediately after the end-Permian extinction. The co-existence of abundant Gakhumella-like microorganisms and oxygen-dependent invertebrates, together with some coccoid-like spheroids, aragonite cement crystal fans, and pyrite framboids indicative of oxygen-poor conditions, implies that oxygenation state of the PTB microbialites is much more complex than previously recognized, demonstrating need for continued multidisciplinary examination of facies changes associated biotic mass extinction. [Display omitted] • PTB microbialite complex comprises bedded stromatolite, digitate dendrolite, thrombolite and giant ooids. • Microbial fabrics include undulating laminated structures, digitate-like branches, and clotted textures. • Ooids are coated by micritic laminae indicating the possibility of a microbe-related origin. • Columnar structures identified as Gakhumella are very abundant and belong to the benthic Pleurocapsale cyanobacteria. • Aragonite crystal fans are distinct, and may have resulted from high bicarbonate in the seawater. [ABSTRACT FROM AUTHOR]

Two upper Middle Permian palaeosols, consisting of coal and pyrite intercalated with a 20 cm thick limestone, were found near Mount Emei in the SW Sichuan Basin, China. The macro- and micromorphology and physico-chemical properties, in conjunction with the mineralogical composition of the palaeosol horizons were investigated. This type of palaeosol is common within the Permian intertidal facies of the Upper Yangtze Craton. The section reflects fluctuations within the range of 0–25 m in relative sea-level, with the depositional environment changing from shallow-marine to littoral, followed by tidal-flat to littoral, and finally to continental volcanic rocks, based on a combination of palaeopedological and carbonate microfacies analyses. Such short-term relative sea-level fluctuations in late Middle Permian times in the SW Sichuan Basin of South China are consistent with the long-term falling trend on a global scale in late Middle Permian times, and may be related to regionally variable subsidence and global cooling. The combination of coastal palaeosol and carbonate microfacies analyses is proposed as an additional tool for estimating the amplitude of sea-level changes. [ABSTRACT FROM AUTHOR]

Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China, where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification, and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone, oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of "depositional fabricselithologyemicrofacies", an association between a fore mound, mound framework, and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions (TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound, exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions (TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain lateral comparison profile and seismic reflection structures in the 2D seismic section, which can provide references for future worldwide exploration. Microbial mounds with larger buildups and thicker vertical reservoirs are typically targeted on the windward margin, while small-sized microbial mounds and flats with better lateral connections are typically focused on the leeward margin. [ABSTRACT FROM AUTHOR]

On October 10 and November 3, 2018, two successive landslides occurred at Baige village, the border between Sichuan Province and Tibet Autonomous Region, in China, which totally dammed the Jinsha River on both occasions. Due to the rapid rise in water level in the "10·10" dammed lake, on October 12, the landslide dam breached naturally with the peak breach flow of about 10,000 m3/s. The residual landslide dam was stacked by the subsequent landslide on November 3, resulting in an even larger dammed lake. Fortunately, the height from the water level in the lake to the dam crest made it possible to construct a spillway to drain the water in the dammed lake to a relatively low level. On November 12, the drainage process began with the peak breach flow of 31,000 m3/s. In this study, based on the detailed records of the breach process of the "11·03" Baige landslide dam and using the developed physically based numerical method, a back analysis was conducted. The numerical method was developed based on the overtopping-induced breach mechanism of landslide dams. An iterative time step algorithm was used to simulate the breach evolution and the hydrograph coupling. The major highlights of the numerical method are the consideration of the breach mechanism of landslide dam, such as the breach morphology evolution process along the streamwise and transverse directions, as well as the variation of soil erodibility with depth and the influence of the presence and absence of a spillway. Comparison of the measured and the calculated results indicated that the numerical method developed in this study can reproduce reasonable breach hydrograph and breach evolution process. The sensitivity analysis showed that the soil erodibility coefficient and the residual dam height significantly influenced the landslide dam breaching process. In addition, it was determined that constructing a spillway before landslide dam breaching is an effective flood hazard mitigation measure for large dammed lakes. However, the availability of the construction conditions and the shape of the spillway should be judged comprehensively according to the rising rate of water level and construction capacity. [ABSTRACT FROM AUTHOR]

The tight sandstones of the Upper Triassic Xujiahe Formation are important gas reservoirs in the western part of the Sichuan Basin, China. However, their diagenesis and the factors controlling diagenetic processes are poorly constrained. The petrological and geochemical nature of diagenetic minerals of the Xujiahe sandstone reservoirs was analysed from 105 core samples of three wells in the Xinchang Gas Field. The lower member, Xu‐2, sandstones have an average framework composition of Q65F16R19, and 47% of the total lithic fragments are volcanic rock fragments (VRFs). In contrast, the upper member, Xu‐4, sandstones have an average framework composition of Q53F0R47 with a near absence of feldspar and VRFs. The main phase of carbonate cementation in the Xu‐2 sandstones is mesogenetic ferroan dolomite, whereas in the Xu‐4 sandstones, it is intergranular poikilotopic calcite. A fair amount (0.97% in bulk rock and 29% in clay fraction) of authigenic kaolinites appear in the Xu‐4 sandstones, but they are completely absent in the Xu‐2 sandstones. The observed textural occurrence of kaolinites, in combination with the positive relationship between δ13C and δ18O in the calcite cements, suggests that meteoric water flushed the Xu‐4 sandstones, resulting in the dissolution of feldspar to a negligible amount. Quartz cementation is more extensive (1.4 vol%) in the Xu‐2 sandstones than in the Xu‐4 sandstones (0.4 vol%). The fluid inclusions within the quartz cements in the Xu‐2 sandstones have a higher homogenization temperature interval (84–217°C) than those in the Xu‐4 sandstones (81–147°C), indicating that quartz cementation continued to affect the Xu‐2 sandstones during deep burial but ceased relatively early in the Xu‐4 sandstones. High‐intensity chlorite authigenesis, feldspar overgrowth, and albitization occur only in the Xu‐2 sandstones, suggesting that the source of these sandstones was primarily from the alteration of VRFs during late‐stage diagenesis. These clear variations in diagenetic features between the Xu‐2 and Xu‐4 members were most likely controlled by the significant variations in their depositional environments (marine vs. non‐marine) and in the original framework compositions. [ABSTRACT FROM AUTHOR]

Combined elemental and isotopic geochemistry of dolomites in the lower Cambrian Longwangmiao Formation, eastern Sichuan Basin with petrographic observations has been investigated to determine the origin of these dolomites. Our data show that these dolomites are mostly located in the middle and upper parts of the Longwangmiao Formation, and most of them commonly occur as crystalline dolostones, whereas they less commonly occur as a dolograinstone. The dolomite contents of the dolostones range from 64 to 97%. The Mg/Ca ratios of these dolomites vary from 0.6 to 1.2, with an average of 0.8. These criteria divide the Longwangmiao dolomites into two types, according to either a positive correlation (type-A) or negative correlation (type-B), which exist between the MgO and CaO contents. Type-A dolomite consists of micritic-to-fine crystals (< 50 μm) of dull-to-no cathodoluminescence. It occurs in association with evaporites and relicts, and has no direct or indirect evidence of formation from carbonate precursors. These features suggest that the type-A dolomite has a parasyngenetic, evaporitic, and near-surface origin. Type-B dolomite consists mainly of medium-to-coarse (50–250 μm) crystals of zoned to uniform, red, or brown luminescence associated with relict textures. High Na concentrations, low Sr concentrations, and Sr/Ca ratios lower than those of type-A seem to indicate that the salinity of the dolomitizing fluid is similar to that of hypersaline seawater. The strongly positive correlation between δ13C and δ18O values, with the occurrence of karst caves and vugs, shows that the Type-B dolomite has been modified by meteoric water. Estimates from δ18O values suggest precipitation at depths of approximately 308 m. These proxies demonstrate that type-B dolomite formed during burial from seepage–reflux of hypersaline seawater, with a minor influence of meteoric water. Type-A dolomite is characterized by micropores and has a low permeability ranging from 0.00195 to 45.00262 × 10−3 μm2, with an average of 0.03730 × 10−3 μm2. It is volumetrically abundant throughout the region, and thus, it represents a potential gas reservoir. High-quality hydrocarbon reservoirs in the region are closely related to type-B dolomite, which is likely to occur in banks at the margins between open and restricted platforms. [ABSTRACT FROM AUTHOR]

The Silurian strata in the Sichuan Basin hold significant exploration potential for shale gas, yet their interrelationships require further investigation. Utilising well data, seismic profiles and existing research, this study examines the structural characteristics of the Sichuan Basin during the Silurian, unconformity distribution characteristics between the Silurian and Permian strata and the extent of Silurian stratum denudation. It then analyses the structural evolution of the basin during the Silurian. The findings of this study include the following: (1) the Leshan–Longnvsi palaeo-uplift expanded from both northwest to southeast and southwest to northeast during the Silurian, whereas the eastern and southern Sichuan depressions migrated south-eastwards. (2) Three angular unconformity areas developed around the Leshan–Longnvsi palaeo-uplift, with the unconformity between the Silurian and Permian strata representing a disconformity. The extent of denudation of the Silurian strata increased from the core of the Leshan–Longnvsi palaeo-uplift to its periphery and decreased around the three angular unconformities. (3) The continuous Leshan–Longnvsi palaeo-uplift controlled the structural evolution of the Sichuan Basin in an extensional dynamic setting during the Silurian. The tensile stress from the passive continental margin at the western edge of the South China Block gradually propagated into the block, affecting Sichuan Basin deposits and Leshan–Longnvsi palaeo-uplift development. • During the Silurian, the Leshan–Longnvsi paleo-uplift expanded from northwest to southeast and from southwest to northeast. • The unconformity between the Silurian and Permian strata is mainly a disconformity, with three angular unconformity areas. • Continuous Leshan–Longnvsi paleo-uplift controlled the structural evolution of the Sichuan Basin during the Silurian. [ABSTRACT FROM AUTHOR]

The marine organic-rich shale of the Longmaxi Formation in the Dingshan area, southeast Sichuan, was studied using scanning electron microscopy (SEM), nitrogen adsorption/desorption and methane isothermal adsorption, mainly emphasizing the nanometer pore structure of organic matter (OM) and its effect on methane adsorption. The results show that the organic-rich shale with high total organic carbon (TOC) content in the high mature stage mainly develops a large number of inkbottle-shaped pores with sizes of 3-50 nm, which provide more effective adsorption sites and storage space for methane adsorption and enhance the adsorption ability of methane. [ABSTRACT FROM AUTHOR]

The composition and carbon isotope distribution of shale gas from the Longmaxi Formation in the Dingshan area were measured, and their responses to thermal maturity (Ro) were analyzed. The results show that the shale gas is mainly composed of methane (97.98–98.99%), ethane, propane and nonhydrocarbon gases (N2 and CO2) and is an organic high temperature oil-type cracked gas. The wetness value [(C2+C3)/(C1+C2+C3) × 100%] ranges from 0.39% to 0.74%. The early (Ro > 1.3%) residual kerogen and crude oil cracking gas was mixed with the late (Ro > 2.0%) secondary cracking gas, resulting in the full inversion of the carbon isotope sequence (δ13C1 > δ13C2 > δ13C3). [ABSTRACT FROM AUTHOR]

The main geological factors controlling the accumulation and yield of marine‐facies shale gas reservoirs are the focus of the current shale gas exploration and development research. In this study, the Wufeng‐Longmaxi Formation in the Dingshan area of southeast Sichuan was investigated. Shale cores underwent laboratory testing, which included the evaluation of total organic carbon (TOC), vitrinite reflectance (Ro), whole‐rock X‐ray diffraction (XRD), pore permeability, and imaging through field emission scanning electron microscopy (FE‐SEM). Based on the results of natural gamma ray spectrum logging, conventional logging, imaging logging, and seismic coherence properties, the exploration and development potential of shale gas in the Dingshan area have been discussed comprehensively. The results showed that (1) layer No. 4 (WF2‐LM4) of the Wufeng‐Longmaxi Formation has a Th/U ratio <2 and a Th/K ratio of 3.5‐12. Graptolites and pyrite are relatively abundant in the shale core, indicating sub‐high‐energy and low‐energy marine‐facies anoxic reducing environments. (2) The organic matter is mainly I‐type kerogen with a small amount of II1‐type kerogen. There is a good correlation among TOC, Ro, gas content, and brittle minerals; the fracturing property (brittleness) is 57.3%. Organic and inorganic pores are moderately developed. A higher pressure coefficient is correlated with the increase in porosity and the decrease in permeability. (3) The DY1 well of the shale gas reservoir was affected by natural defects and important late‐stage double destructive effects, and it is poorly preserved. The DY2 well is located far from the Qiyueshan Fault. Large faults are absent, and upward fractures in the Longmaxi Formation are poorly developed. The well is affected by low tectonic deformation intensity, and it is well preserved. (4) The Dingshan area is located at the junction of the two sedimentary centers of Jiaoshiba and Changning. The thickness of the high‐quality shale interval (WF2‐LM4) is relatively small, which may be an important reason for the unstable production of shale gas thus far. Based on the systematic analysis of the geological factors controlling high‐yield shale gas enrichment in the Dingshan area, and the comparative analysis with the surrounding typical exploration areas, the geological understanding of marine shale gas enrichment in southern China has been improved. Therefore, this study can provide a useful reference for shale gas exploration and further development. [ABSTRACT FROM AUTHOR]

Large quantities of saddle dolomite, dolomite, calcite, celestite, fluorite, barite, quartz, and pyrite occur as fracture fillings in the fourth member of the Middle Triassic Leikoupo Formation in the Yuanba area, northeast Sichuan. They were found either as single mineral or mineral assemblages. The properties, origin, and evolution of the fluids from which these fracture fillings were precipitated were studied using a variety of methods, including polarized light microscopy, cathodoluminescence microscopy, fluid inclusions, and stable isotope analysis. Homogenization temperatures of the liquid–gas inclusions trapped within the dolomite ranged from 112 to 138 °C. Based on this temperature range and the oxygen isotope data, the δ18O values of the fluids from which the dolomite precipitated were determined to be between −5‰ and 7‰ (Standard Mean Ocean Water). The study suggests that the fracture‐filling dolomite, ubiquitous in the fourth member of the Middle Triassic Leikoupo Formation in the study area, was produced from high‐temperature, high‐salinity brines. These brines were interpreted to have originated from the mixtures of hot brines trapped in rock formations and hydrothermal fluids from deep sources and to have become enriched in strontium during diagenesis. [ABSTRACT FROM AUTHOR]

In recent years, significant efforts have been directed towards extracting deep shale gas (SG) in Luzhou. Understanding the factors influencing the accumulation and preservation of SG in the section extending from the Upper Ordovician Wufeng (WF) Formation (Fm) through the Lower Silurian Longmaxi (LMX) Fm is crucial for its large‐scale, profitable development. The shale layers in the LMX Fm located in the Luzhou‐Zigong area in the southern part of the Sichuan Basin have undergone unique geological processes, including deep deposition, intensive uplift, erosion and deformation. The Luzhou block, situated in the low‐fold zone in southern Sichuan between the southern slope of the paleo‐uplift in central Sichuan and the down‐warping fold zone in south‐eastern Sichuan, was studied using seismic, well‐log, drilling and core analysis and test data to understand its tectonic, sedimentary, reservoir and fracture characteristics and identify the principal factors controlling gas accumulation in this area. The study found that SG in the Luzhou block is primarily distributed in the WF Fm through the Longyi1 sub‐member. Class I continuous reservoirs, 2.6–20.3 m in thickness, are mainly found in the Longyi11–13 sublayers and those with large continuous thickness produced high yields during tests. Gentle anticlinal zones and wide, gentle tectonic structures with relatively high‐pressure coefficients have formed in this area. High‐angle fractures (HACs) in this area tend to accumulate free gas and, therefore, facilitate the accumulation and production of SG. The study concludes that the continuous thickness of Class I reservoirs and natural HACs controlled by the centre of the deep‐water continental shelf are the primary factors controlling SG accumulation in the Luzhou block. [ABSTRACT FROM AUTHOR]

Yibin Yacai is one of the most popular pickled vegetables in Sichuan made from special local stem mustard via spontaneous fermentation. The final quality of the Yibin Yacai product depends on every manufacturing process that affects the microbial communities during fermentation. In this study, the effects of brown sugar addition and fermentation time on physicochemical quality, flavor, and microbial communities of Yibin Yacai under five different fermentation conditions were investigated. The brown sugar addition can effectively increase the activities of microorganisms such as Lactobacillus and Debaryomyces , resulting in an increase in lactic acid content, sweet amino acids and umami amino acids. Furthermore, fermentation time plays a critical role in determining their physicochemical quality and flavor. The Yibin Yacai samples fermented for 5 years present the highest content of reducing sugar, amino acid nitrogen, esters, aldehydes, and olefins, while having the lowest salinity. These results indicate that the brown sugar addition and fermentation time could significantly influence the physicochemical and flavor qualities of the Yibin Yacai by tuning microbial communities during fermentation. These findings reveal the importance of controlling manufacturing processes for traditionally fermented Yibin Yacai and provide a new perspective on the technological innovation of fermented Yibin Yacai. • Yibin Yacai is one of the four pickled vegetables in Sichuan. • A correlation analysis of metabolomics and microbe was performed. • Brown sugar addition and fermentation time affect the quality of Yibin Yacai. • Brown sugar addition enriches the fermented flavor of Yibin Yacai. • Yibin Yacai fermented with brown sugar for five years has the best quality. [ABSTRACT FROM AUTHOR]

Giardia duodenalis and Cryptosporidium spp. are common gastrointestinal protozoa in mammals. Many studies have been conducted on the distribution of G. duodenalis and Cryptosporidium spp. genotypes in sheep and cattle. However, in China, information about molecular characterization and genetic analysis of G. duodenalis and Cryptosporidium spp. in goats is limited. In this study, 342 fecal samples from adult goats were collected from 12 farms in Sichuan Province, China. The occurrence of G. duodenalis and Cryptosporidium spp. in adult goats was 14.9% (51/342) and 4.7% (16/342), respectively. All G. duodenalis were identified as assemblage E, with two novel genotypes (assemblages E17 and E18) being detected at the beta-giardin (bg) locus. Based on three loci—beta-giardin (bg), triose phosphate isomerase (tpi), and glutamate dehydrogenase (gdh)—multilocus sequence typing revealed three novel multilocus genotypes (MLGs) of assemblage E (MLG-E1, E2, E3 (sc)). Small Subunit (SSU) rRNA-based PCR identified two Cryptosporidium species, namely C. xiaoi (11/16) and C. suis (5/16). This study is not only the first to report C. suis infection in adult goats in China but is also the first to use the MLG approach to identify G. duodenalis in adult goats. [ABSTRACT FROM AUTHOR]

Pternopetalum porphyronotum, a new species from Dafengding Nature Reserve, Sichuan Province, China, is proposed and described. Diagnostic morphological characters, full description and detailed illustrations are provided. Pternopetalum porphyronotum is quite different from the other known species of this genus by the following 2 characters: the 1‐pinnate leaves and the abaxially purple–red leaflets (paler along the edge). A comparison between the new species and the two most similar congeners P. subalpinum and P. gracillimum are presented. The novelty was found only on two cliffs in the much human‐affected outskirst of the nature reserve and is asessed as Critically Endangered (CR). [ABSTRACT FROM AUTHOR]

PM2.5 is an important indicator reflecting changes in air quality. In recent years, affected by climate change and human activities, the problem of environmental pollution has become more and more prominent. In this study, the PM2.5 data from 2000 to 2018 obtained by satellite remote sensing inversion algorithm were selected to analyze the temporal and spatial distribution of PM2.5 in China. The results show that the areas with higher PM2.5 concentrations were mainly in the North China, the Sichuan Basin, and the Tarim Basin. The areas with a significant increase in PM2.5 were mainly in the Northeast China, while the areas with a significant decrease were mainly in the Sichuan Basin and southeastern Gansu. The change of PM2.5 in southern China was not significantly correlated with the change of population and economy, while PM2.5 in Northeast China increases with the increase of population and economy. In 2000, 2005, 2010, and 2015, the proportion of the population polluted by PM2.5 was 8.65%, 7.2%, 22.99%, and 9.75%, respectively. The year with the highest percentage (37.63%) of population when air quality reached EXCELLENT was 2015. When the PM2.5 spatial cluster number was six, it can better reflect the PM2.5 spatial distribution state. The places with large changes in PM2.5 spatial clustering were mainly in the Northeast China, Sichuan Basin, and Tarim Basin, which were also areas with large changes in PM2.5. This study provides an important reference for atmospheric environmental monitoring and protection. • The temporal and spatial variation patterns of PM2.5 in China from 2000 to 2018 were obtained. • The relationship between PM2.5 and population and GDP was obtained. • The change rule of the population affected by PM2.5 was obtained. • We used cluster analysis method to obtain PM2.5 spatial clustering status. [ABSTRACT FROM AUTHOR]

Background: Although diagnosis and treatment services for tuberculosis (TB) are provided free of charge in most countries, direct non-medical and indirect costs due to absenteeism, also place a significant burden on patients and their families. Sichuan Province has the second highest incidence of TB in China, with an incidence of approximately 100 cases per 100 000 people. However, there are limited research on out-of-pocket expenditure (OOPE) and its influencing factors in TB patients in Sichuan Province. Methods: A retrospective cross-sectional study was conducted on TB patients in designated medical institutions for TB in Sichuan Province from 2017-2021. A face-to-face questionnaire was conducted to obtain the information related to hospitalization of patients, and the multi-level regression model was used to analyse the factors that influence OOPE and total out-of-pocket expenditure (TOOPE) of TB patients. Results: A total of 2644 patients were investigated, and 74.24% of TB patients and their families experienced catastrophic total costs due to TB. The median total cost was 9223.37 CNY (1429.98 USD), in which the median direct and indirect costs of TB patients were 10185.00 CNY (1579.07 USD) and 2400.00 CNY (372.09 USD), respectively, and indirect costs contributed to 43% of total costs. The median OOPE and TOOPE costs were 6024.00 CNY (933.95 USD) and 11890.50 CNY (1843.49 USD), respectively. OOPE and TOOPE had common influencing factors including whether the patient's family had four or more members, a history of hospitalization, combination with other types of TB, the number of visits before diagnosis, and co-occurrence with chronic disease. Conclusions: The OOPE and TOOPE for TB patients and their families in Sichuan Province are still heavy. In the long run, it is necessary to strengthen education and awareness campaigns on TB related knowledge, disseminate basic medical knowledge to the public, improve healthcare-seeking behavior, and enhance the healthcare infrastructure to improve the accuracy of TB diagnosis and reduce the significant OOPE and TOOPE faced by TB patients and their families in Sichuan Province. [ABSTRACT FROM AUTHOR]

• The pellicle-forming related microbes in traditional home-made Chinese paocai were first identified through metagenomic sequencing. • The pellicle formation related microorganisms mainly belonged to six genus, including Kazachstani a, Lactobacillus, Pichia , Candida , Lachancea and Saccharomyces. • Baijiu was effective to restrain the pellicle and improve the flavor of paocai. The occurrence of pellicle on the surface of paocai brine is a common undesirable phenomenon during the multi-rounds of paocai fermentation, which is mainly caused by the growth of microorganisms related to pellicle formation. But the detailed information on these microorganisms and volatile components produced by them, as well as the changes of the microorganisms during the process of paocai recovery, are still rare in the literature. Therefore, the purpose of this study was (1) to analyze the pellicle formation related microorganisms by comparing the differential microorganisms in initial brine and the brine when pellicle occurred through metagenomic sequencing technology, (2) to explore the changes of microorganisms in the fermentation system after addition Baijiu and/or salt, and (3) to further detect the VOCs in paocai samples by gas chromatography-mass spectrometry (GC–MS). The relationship between VOCs and the selected marker microorganisms was also determined. The results showed that the diversity of fungi was increased when pellicle formed, the pellicle formation related microorganisms mainly belonged to six genus, including Kazachstani a, Lactobacillus, Pichia , Candida , Lachancea , and Saccharomyces. Apart from the unknown function and basic life activities of microorganisms, the metabolic activities of these pellicle formation related microorganisms were mainly carbohydrate transport and metabolism, and amino acid transport and metabolism. The growth of pellicle formation related microorganisms could be inhibited by adding Baijiu (1.5% v/v), but the addition of salt (7% salt (w/v) did not promote this inhibitory effect. Through PCA analysis, it was found that the VOCs of paocai were significantly affected by adding Baijiu and Baijiu and salt. The undesirable smell at the beginning of pellicle formation may be related to Propanoic acid, hexyl ester, 1,3-Dimethyl-1-cyclohexene, Oxime-, methoxy-phenyl- and Phenylethyl Alcohol. [ABSTRACT FROM AUTHOR]

The Xinjie layered intrusion is one of a number of major ultramafic-mafic bodies hosting Fe-Ti-V deposits and Cu-Ni-PGE sulfide deposits in the Pan-Xi (Panzhihua-Xichang) area of the Sichuan Province, SW China. The Xinjie ultramafic-mafic layered intrusion, genetically related to the Permian plume-related Emeishan flood basalts, consists of three lithological cycles, each representing a sequence from ultramafic to mafic-felsic composition. The basal part of the intrusion is composed of three lithological units, namely, the Marginal Unit (MU), Peridotite Unit (PeU) and Pyroxenite Unit (PyU). In the present study, three major PGE-mineralised Cu-Ni sulfide layers were discovered within the Marginal and Pyroxenite Units. The major base-metal sulfides (BMS) comprise chalcopyrite, pyrrhotite, and pentlandite. Detailed microscopic and microprobe analyses revealed the presence of the sperrylite and Pd-Pt-Bi-Te minerals (merenskyite, moncheite, and michenerite). These PGMs are commonly associated with the BMS, or magnetite coexisting with BMS in the PGE-enriched layers. The 1:1 substitution between Pt and Pd, as well as between Te and Bi, confirms the complete solid-solution series between moncheite and merenskyite. The textural association of the PGMs with BMS and Fe-Ti oxides (magnetite) suggests that the PGMs may have crystallised slightly later than the hosting magnetite and BMS. The formation of magnetite may have played an important role in producing the sulfur-saturated melt and the PGEs thus concentrated in the sulfide liquid during the crystallisation history. It is therefore suggested that the Cu-Ni-PGE-bearing layers in the basal part of the Xinjie intrusion were generated by magma evolution processes. [ABSTRACT FROM AUTHOR]

Under hot, deep-basin conditions, hydrogen-to-carbon ratios of residual kerogen are low. Whether ubiquitous water in sedimentary environments contributes hydrogen directly to hydrocarbon gas formation through organic-inorganic interactions is, therefore, critical for natural gas generation. Accordingly, we conducted laboratory experiments on immature to overmature kerogens at 300–600°C and 700 bar to examine the chemical interactions between kerogens and fluid under varying redox states and hydrothermal conditions. Mineral buffers, comprised of magnetite-hematite, nickel‑nickel oxide, cobalt‑cobalt oxide, and molybdenum‑molybdenum trioxide, were added to the experiments to control the redox state of the fluid from geologically reasonable to generally excessive values. The kerogens and mineral buffers were spatially isolated using double-capsule techniques to prevent contact catalysis. Our results indicated that chemical interactions between kerogens and water depended strongly on the kerogen thermal maturity and fluid redox state. The chemical interactions of overmature kerogens with reducing water were stronger than those of immature kerogens, which could be ascribed to the weaker competitive transfer of hydrogen from organics to organics than from water to organics. Unexpectedly high amounts of hydrocarbon gas were generated by incorporating water-derived hydrogen in the pyrolysis of overmature kerogens, and the yields increased under low to high reducing fluid conditions for a given temperature. Along with the increasing thermal maturity, residual kerogen eventually became ineffective for hydrocarbon gas generation through reduction reactions. Demethylation, bridge bond cleavage reaction, aromatic structure ring opening reactions in residual kerogen and subsequent redox reaction of intermediate products with reducing fluids is evidenced as the possible reaction mechanisms. The produced hydrocarbon gas under f H 2 level of oilfield water is characterized by high dryness (99 mol%) and more-enriched 13C in CH 4 compared with precursors. Natural gas deep within the Sichuan and Appalachian basins with similar characteristics suggests that our simulated organic–inorganic interactions could occur widely under natural conditions. Consequently, a potentially prolific source of natural gas may be formed by the overmature source rocks in the deep basin and fluid redox should be considered for gas potential evaluation of overmature source rocks. • The influence of fluid redox and kerogen thermal maturity on the reactions of kerogens and water. • Overmature kerogen forms hydrocarbon gas by incorporating water-derived hydrogen. • Organic–inorganic interactions facilitate incorporation of water-derived hydrogens. • Reducing fluid conditions enhance hydrogen transfer efficiency of such interactions. [ABSTRACT FROM AUTHOR]

Six species of Lathrobium Gravenhorst, 1802 from the Emei Shan, Sichuan, are described and illustrated: L. iunctum Assing & Peng sp. n., L. coniunctum Assing & Peng sp. n., L. conexum Assing & Peng sp. n., L. ensigerum Assing & Peng sp. n., L. hastatum Assing & Peng sp. n., and L. bisinuatum Assing & Peng sp. n. Based on their primary and secondary sexual characters, they represent two distinct lineages, each of them comprising three species. A key to the species recorded from the Emei Shan is provided. [ABSTRACT FROM AUTHOR]

Three new species of the genus Lathrobium Gravenhorst, 1802 from Sichuan Province, Southwest China are described and illustrated: L. acutissimum sp. n., L. hailuogouense sp. n. and L. labahense sp. n. A checklist of Chinese Lathrobium is provided. [ABSTRACT FROM AUTHOR]

Topography is a critical factor that determines the characteristics of regional soil formation. Small-scale topographic changes are referred to microtopographies. In hilly mountainous regions, the redistribution of water and soil materials caused by microtopography is the main factor affecting the spatial heterogeneity of soil and the utilization of land resources. In this study, the influence of microtopography on pedogenesis was investigated using soil samples formed from mudstones with lacustrine facies deposition in the middle of the Sichuan Basin. Soil profiles were sampled along the slopes at the summit, shoulder, backslope, footslope, and toeslope positions. The morphological, physicochemical, and geochemical attributes of profiles were analyzed. The results showed that from the summit to the toeslope, soil thickness increased significantly and profile configuration changed from A–C to A–B–C. The total contents of Ca and Na decreased at the summit, backslope, and footslope, while the total contents of Al, Fe and Mg showed an opposite trend. On the summit and shoulder of the hillslope, weathered materials were transported away by gravity and surface erosion, exposing new rocks. As a result, soil development in these areas was relatively weak. In flat areas such as the footslope and toeslope with sufficient water conditions, the addition of weathered components and the prolonged contact between water, soil, and sediment led to further chemical weathering, resulting in highly developed characteristics. Microtopography may influence physicochemical properties, chemical weathering, and redistribution of water and materials, causing variations in pedogenic characteristics at different slope positions. [ABSTRACT FROM AUTHOR]

Objective To analyze the incidence trend of cancer from 2015 to 2020 in Sichuan Province and provide a reference for prevention and control of cancer. Methods Based on the cancer-related case information data on the Homepage of medical records in Sichuan Province from 2015 to 2020, the crude incidence rate was calculated, and the average annual change percentage (AAPC) of incidence rates was analyzed with Joinpoint 4.2.0.1. Results The new cancer cases in Sichuan Province increased from 181 490 in 2015 to 276 770 in 2020, and the incidence rate increased from 198. 57/105 in 2015 to 304.76/105 in 2020. From 2015 to 2020, the average annual percentage change (AAPC) was 7.514%, 6.751%, 8.611%, 4.713%, and 6.838%, respectively. The incidence of cancer in the Chengdu Plain Economic Zone and the Northwest Sichuan Ecological Economic Zone showed a rising trend, AAPC values with statistical significancebeing 7.549% and 9. 668%, respectively. From 2015 to 2020, the incidence rate of lung cancer, colorectal cancer, breast cancer, cervical cancer and prostate cancer in Sichuan Province showeda rising trend, with AAPC values of 11.220% (95% CI; 5.866-16.845), 6.606% (95% CI: l.395-13.202), 6.322% (95% CI: 1.411-11.472), 5.765% (95% CI: l.431-10.284) and 13. 222% (95% CI : 7.396-19.364), respectively. Conclusion The incidence of cancer in Sichuan Province shows a rising trend, and the prevention and control situation is grim. Lung cancer, digestive system cancer, breast cancer, cervical cancer and prostate cancer are the dominant cancer types in Sichuan Province, and specific prevention, control and screening should be strengthened. [ABSTRACT FROM AUTHOR]

Simple Summary: The genus Diploderma Hallowell, 1861 (Squamata, Agamidae), currently consists of 46 species, which are distributed across East Asia (inclusive of Japan) and the northern part of the Indochinese Peninsula, primarily inhabiting dry valley regions in Western China. This article introduces a novel species of Diploderma based on its unique morphological features and molecular evidence, discovered in the lower valley of the Dadu River in Sichuan Province, Western China. Phylogenetic analysis using ND2 data suggests that this new taxon is distinct from its congeners. Morphologically, the new species can be differentiated from other Diploderma species by an assemblage of 46 specific characteristics. Principal component analysis (PCA) further demonstrates that this new species is clearly distinguishable from its closest relative, D. splendidum. Given these multiple lines of evidence, we describe this species from the lower Dadu River valley as a newly identified species, D. daduense sp. nov. This discovery brings the total number of recognized species within the genus Diploderma to 47. This study describes a novel species of Diploderma (Squamata, Agamidae) from the lower valley of the Dadu River of the Sichuan Province of Western China based on its distinct morphological features and molecular evidence. D. daduense sp. nov. can be distinguished from its congeners by its tympanum concealed; head mainly green-yellow, supplemented by black; skin folds under the nuchal and dorsal crest obviously present in adult males only, its vertebral crest discontinuous between nuchal and dorsal sections with a distinct gap; transverse gular fold present but not obvious in some individuals; gular spot absent in both sexes; dorsolateral stripes green-yellow anteriorly, cyan in the center and blurry off-white posteriorly in adult males, the upper edge of dorsolateral stripes strongly jagged in adult males; no radial stripes around the eyes; inner-lip coloration smoky-white, and the coloration of the tongue and oral cavity as a light-flesh color in life; bright green-yellow transverse stripes on dorsal body in males; black patches are evenly distributed along the vertebral line between the dorsolateral stripes from the neck to the base of the tail in males; beech-brown or gray-brown line along the vertebral line with heart-shaped or diamond-shaped black patches on the dorsal body in females; and supratemporals fewer than four on at least one side. The phylogenetic tree based on mitochondrial ND2 sequences indicates that D. daduense sp. nov. forms an independent clade with strong support 1/100 in ML bootstrap/Bayesian posterior probability and is the sister group to D. splendidum. At the inter-species level, the p-distance is at least 6.95%, further confirming that an independent species had been identified. Our work raises the number of species within the genus Diploderma to 47. [ABSTRACT FROM AUTHOR]

Rapid and accurate identification of landslides is an essential part of landslide hazard assessment, and in particular it is useful for land use planning, disaster prevention, and risk control. Recent alternatives to manual landslide mapping are moving in the direction of artificial intelligence—aided recognition of these surface processes. However, so far, the technological advancements have not produced robust automated mapping tools whose domain of validity holds in any area across the globe. For instance, capturing historical landslides in densely vegetated areas is still a challenge. This study proposed a deep learning method based on Light Detection and Ranging (LiDAR) data for automatic identification of historical landslides. Additionally, it tested this method in the Jiuzhaigou earthquake-hit region of Sichuan Province (China). Specifically, we generated a Red Relief Image Map (RRIM), which was obtained via high-precision airborne LiDAR data, and on the basis of this information we trained a Lightweight Attention U-Net (LAU-Net) to map a total of 1949 historical landslides. Overall, our model recognized the aforementioned landslides with high accuracy and relatively low computational costs. We compared multiple performance indexes across several deep learning routines and different data types. The results showed that the Multiple-Class based Semantic Image Segmentation (MIOU) and the F1_score of the LAU-Net and RRIM reached 82.29% and 87.45%, which represented the best performance among the methods we tested. [ABSTRACT FROM AUTHOR]

With rapid rural urbanization and new rural construction, the commercial energy consumption of rural residents shows a trend of rapid growth, and China's rural areas are also faced with environmental challenges brought by the increase of commercial energy consumption. China's commercial energy consumption behavior of rural residents has also undergone tremendous changes. However, scholars have neglected the research on rural residents' commercial energy consumption intention from a micro perspective. Therefore, this study takes the 5 villages in Chengdu out of the 100 representative villages in the Sichuan province as examples. From the perspective of the head of a family of permanent rural residents, extended planned behavior theory, exploratory factor analysis, and structural equation modeling are used to explore the influencing factors of rural resident commercial energy consumption intention and their relationship. Findings show that subjective norm, perceived behavioral control (PBC), and habit significantly affect residents' behavioral intention. Habits significantly influence subjective norms and PBC. Therefore, in the new rural construction, rural residents are the main body and participants of energy consumption. Local government departments should plan reasonably according to the needs and characteristics of residents, constantly improve commercial energy infrastructure, improve service level, and further strengthen farmers' attitude and satisfaction toward commercial energy. Moreover, they should increase the publicity and education of commercial energy, advocate green housing, and promote energy saving consumption reduction, and sustainable development in new rural areas. [ABSTRACT FROM AUTHOR]

• Particle characteristics of clay rock derived soils were analyzed. • A determination method of multi-mineral sand particles (MSPs) was established. • MSP content in shale-derived soils was higher than that in mudstone-derived soils. • Characteristics of clay rock soils lie on the process of diagenesis and pedogenesis. Multi-mineral sand particles (MSPs), commonly found in upland soils, can change the erosion properties, structure, moisture level, porosity, and permeability of soil; however, their effects are generally neglected in previous studies. In this study, we explored the morphology using scanning electron microscopy (SEM), particle size distribution (PSD), aggregation state, and mineralogy of soils derived from two types of clay rocks containing MSPs: shale and mudstone. The results showed that: (1) small lamellate bodies formed granules and blocks in a face-to-face or side-to-side manner and that the aggregation particles ranged from several to tens of microns in diameter, which increased gradually in a downslope direction; (2) the sand content in shale- and mudstone-derived soils decreased from 41.0% and 31.3%, respectively, on the summit to 19.6% and 18.4%, respectively, on the toeslope, whereas their clay content increased from 23.3% and 20.2% to 45.0% and 38.9%, respectively; (3) regarding the aggregation states of soil particles, the content of 0.25–2 mm MSPs in the shale- and mudstone-derived soils decreased from 62.9% and 45.2%, respectively, on the summit to 7.1% and 1.4%, respectively, on the toeslope, with averages of 42.3% and 20.8%, respectively. The content of 0.25–2 mm aggregates in the shale- and mudstone-derived soils increased from 9.1% and 6.2%, respectively, on the summit to 44.4% and 21.1%, respectively, on the toeslope, with averages of 21.5% and 14.2%, respectively; and (4) the mineralogy of the clay rock-derived soils and MSPs was generally dominated by illite, montmorillonite, vermiculite and calcite, which was similar to the mineralogy of the parent rocks. Therefore, a large amount of MSPs was found in clay rock-derived soils whose particle characteristics were determined by the environment of diagenesis and the physical weathering of pedogenesis. [ABSTRACT FROM AUTHOR]

It is unclear about the mutual impact of COVID-19 related psychological stress and infection on mental health of adolescent and youth students. This study aimed to explore the mutual impact of COVID-19 related psychological stress and infection on mental health problems among students. This study was conducted from December 14, 2022 to February 28, 2023 in Sichuan, China. Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, PTSD Checklist for DSM-5, Insomnia Severity Index, and Internet Addiction Test were used. Participants were grouped by COVID-19 infection and psychological stress level. The differences among groups were compared, and logistic regression analysis was used to investigate risk factors for depression, anxiety, PTSD and insomnia among groups. Of 90,118 participants, 82,873 (92.0 %) finished the questionnaires and were included in the study. Of 82,873 participants, 33,314 (40.2 %) reported to be infected with COVID-19. Participants had depression symptoms (38.1 %), anxiety symptoms (31.8 %), PTSD (33.9 %), insomnia (34.0 %), and internet addiction (60.3 %). Compared with participants uninfected with low psychological stress level, the risk for symptoms of depression, anxiety, PTSD and insomnia increased by 9.6 %, 12.3 %, 6.6 %, and 12.0 % in participants infected with low psychological stress level (p < 0.001), 106.8 %, 125.9 %, 125.2 %, and 95.7 % in participants uninfected with high psychological stress level (p < 0.001), and 147.3 %, 161.1 %, 158.7 %, and 141.0 % in participants infected with high psychological stress level (p < 0.001). This study is a cross-sectional design, and no causal associations should be inferred. Infection status was based on self-report of participants with infectious symptoms. COVID-19 related psychological stress and infection per se have mutually overlapping impacts on mental health problems among students. Further health policies and psychosocial interventions should be developed to reduce mutually overlapping impact and improve the long-term mental health among students. • It is unclear about the mutual impact of COVID-19 infection and psychological stress on individuals' mental health • This study supports the mutual overlapping theory (MOT) of COVID-19 infection and psychological stress • The overlap of COVID-19 infection and psychological stress may cause more severe mental health problems • Health policies and interventions should be developed for reducing the impact of infection and psychological stress [ABSTRACT FROM AUTHOR]

When the thermal maturity of the Longmaxi Formation in the southern Sichuan Basin is too high, the pore structure of shale becomes poor. Therefore, to investigate the effect of organic matter thermal maturity on shale pore structure, a study was conducted. Using the Longmaxi Formation shale in the southern Sichuan Basin as an example, the intrinsic relationship between shale porosity, pore structure parameters, organic matter laser Raman maturity, and organic matter graphitization degree was examined using X-ray photoelectron spectroscopy, particle helium porosity measurement, organic matter micro-laser Raman spectroscopy, and gas adsorption experiments. The results indicate that thermal maturity is the macroscopic manifestation of the graphitization degree of organic matter, and the correlation coefficient between the two is 0.85. A thermal maturity of 3.5% (with a corresponding organic matter graphitization degree of 17%) aligns with the highest values of shale porosity, pore volume, and pore-specific surface area across all pore size conditions. The evolution model of shale pore structure can be divided into two stages. The first stage is characterized by a thermal maturity between 2.0% and 3.5% (with a corresponding degree of graphitization of organic matter between 0% and 17%). During this stage, the number and connectivity of micro-macropores increase with increasing thermal maturity. The second stage is marked by a thermal maturity between 3.5% and 4.3% (with a corresponding degree of graphitization of organic matter between 17% and 47.32%). Basement faults are present, leading to abnormally high thermal maturity, poor preservation conditions, continuous generation of micropores, better connectivity, and a reduced number of pores. Medium macropores with good connectivity suffer from gas loss in the fracture network, leading to the collapse and disappearance of pores. The results mentioned in the statement have an important guiding role in the efficient exploration of shale gas in the Longmaxi Formation in the southern Sichuan Basin. [ABSTRACT FROM AUTHOR]

The novel HLA‐C*08:242 allele was identified in an individual from the Sichuan province of China. [ABSTRACT FROM AUTHOR]

The Emeishan large igneous province (ELIP) is among the prominent large igneous provinces in the world and has been associated with mantle plume activity. In this study we investigated the impact of the Emeishan mantle plume on generating the sedimentary rock suites of the eastern Sichuan Basin. We present petrology, detrital zircon U – Pb ages, trace elements, and Hf isotopic compositions of the Middle-Late Permian sedimentary sequences in the Huayingshan region to constrain the provenance and characterize the depositional response to the Emeishan mantle plume activity. The detrital zircon U – Pb ages of the Middle Permian Maokou Formation indicate that terrigenous detritus was mainly sourced from the Kangdian paleoland in the southwestern margin of South China. Detrital zircon grains from the bottom of the Late Permian Longtan Formation yield a lower intercept age of 257 ± 28 Ma, interpreted as the contemporaneous metamorphism related to the ELIP magma. The detrital zircon U – Pb ages of the middle part of the Longtan Formation are characterized by unimodal age spectra with a peak at 259 Ma. Provenance analysis indicates that the Longtan Formation was mainly sourced from the Emeishan volcanic rocks in the Huayingshan region. We propose that the Kangdian paleohigh may have been regionally uplifted as the result of the pre-eruption rise of the Emeishan mantle plume in the late Middle Permian. Moreover, this paleohigh was translated into a denuded zone and provided voluminous detritus into the eastern Sichuan Basin. In the early Late Permian, the ELIP magmas upwelled and outpoured from the Huayingshan fault, and flowed past the peripheral rocks to the low terrain in the Huayingshan region. The ELIP volcanic rocks in the Huayingshan region underwent intense post-eruption erosion, resulting in the deposition of voluminous volcanic detritus in the eastern Sichuan Basin. [ABSTRACT FROM AUTHOR]

The optimal choice of the planetary boundary layer (PBL) parameterization scheme is of particular interest and urgency to a wide range of scholars, especially for many works involving models. At present, there have been many works to evaluate the PBL schemes. However, little research has been conducted into a more comprehensive and systematic assessment of the performance capability of schemes in key regions of China, especially when it comes to the differences in the mechanisms of the schemes themselves, primarily because there is scarcely sufficient observational data, computer resources, and storage support to complete the work. In this companion paper (i.e., Part 1), four typical schemes (i.e., YSU, ACM2, BL, and MYJ) are selected to systematically analyze and evaluate near-surface meteorological parameters, PBL vertical structure, PBL height (PBLH), and turbulent diffusion coefficient (TDC) in five key regions of China (i.e., North China Plain, NCP; Yangtze River Delta, YRD; Sichuan Basin, SB; Pearl River Delta, PRD and Northwest Semi-arid region, NS) in different seasons (i.e., January, April, July, and October). The differences in the simulated 2 m temperatures between the nonlocal closure schemes are mainly affected by the downward shortwave radiation, but to compare the nonlocal closure schemes with the local closure schemes, the effect of sensible heat flux needs to be further considered. The 10 m wind speed is under the influence of factors like the momentum transfer coefficient and the integrated similarity functions at night. The wind speeds are more significantly overestimated in the plains and basin, while less overestimated or even underestimated in the mountains, as a result of the effect on topographic smoothing in the model. Moreover, the overestimation of small wind speeds at night is attributable to the inapplicability of the Monin–Obukhov similarity theory (MOST) at night. The model captures the vertical structure of temperature well, while the wind speed is outstandingly overestimated below 1000 m, largely because of the TDC. The difference between the MOST and the mixing length theory, PBLH, and Prandtl number is cited as the reason for the difference between the TDC of the YSU and ACM2 schemes. The TDCs of the BL and MYJ schemes are affected by the mixing length scale, which of BL is calculated on the basis of the effect of buoyancy, while MYJ calculates it with the consideration of the effect of the total turbulent kinetic energy. The PBLH of the BL scheme is better than the other schemes because of the better simulation results of temperature. In general, to select the optimal scheme, it is necessary to offer different options for different regions with different focuses (heat or momentum). The first focus is on the temperature field. The BL scheme is recommended for January in the NCP region, especially for Beijing, and the MYJ scheme is better for the other 3 months. The ACM2 scheme would be a good match for the YRD region, where the simulation differences between the four schemes are small. The topography of the SB region is more complex, but for most of the areas in the basin, the MYJ scheme is proposed, and if more stations outside the basin are involved, the BL scheme is recommended. The MYJ scheme is applied to the PRD region in January and April, and the BL scheme in July and October. The MYJ scheme is counseled for the NS region. The second focus is the wind field. The YSU scheme is recommended if the main concern is the near-surface layer, and the BL scheme is suggested if focusing on the variation in the vertical direction. The final evaluation of the parameterization scheme and uncertainties will lay the foundation for the improvement of the modules and forecasting of the GRAPES_CUACE regional model developed independently in China. [ABSTRACT FROM AUTHOR]

Classic heatstroke (CHS) is a life-threatening illness characterized by extreme hyperthermia, dysfunction of the central nervous system and multiorgan failure. Accurate predictive models are useful in the treatment decision-making process and risk stratification. This study was to develop and externally validate a prediction model of survival for hospitalized patients with CHS. In this retrospective study, we enrolled patients with CHS who were hospitalized from June 2022 to September 2022 at 3 hospitals in Southwest Sichuan (training cohort) and 1 hospital in Central Sichuan (external validation cohort). Prognostic factors were identified utilizing least absolute shrinkage and selection operator (LASSO) regression analysis and multivariate Cox regression analysis in the training cohort. A predictive model was developed based on identified prognostic factors, and a nomogram was built for visualization. The areas under the receiver operator characteristic (ROC) curves (AUCs) and the calibration curve were utilized to assess the prognostic performance of the model in both the training and external validation cohorts. The Kaplan‒Meier method was used to calculate survival rates. A total of 225 patients (median age, 74 [68–80] years) were included. Social isolation, self-care ability, comorbidities, body temperature, heart rate, Glasgow Coma Scale (GCS), procalcitonin (PCT), aspartate aminotransferase (AST) and diarrhea were found to have a significant or near-significant association with worse prognosis among hospitalized CHS patients. The AUCs of the model in the training and validation cohorts were 0.994 (95% [CI], 0.975–0.999) and 0.901 (95% [CI], 0.769–0.968), respectively. The model's prediction and actual observation demonstrated strong concordance on the calibration curve regarding 7-day survival probability. According to K‒M survival plots, there were significant differences in survival between the low-risk and high-risk groups in the training and external validation cohorts. We designed and externally validated a prognostic prediction model for CHS. This model has promising predictive performance and could be applied in clinical practice for managing patients with CHS. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) caused by Fusarium species, seriously threatens the safety of wheat (Triticum aestivum) production. Resistant cultivars and fungicides are frequently used to control these FHB pathogens. However, Fusarium species have been adapting the current FHB control approaches in a manner that raises concern for future FHB control strategies, which could lead to a greater risk of FHB outbreaks. In this study, a total of 521 strains of Fusarium were isolated from Sichuan province of China, to investigate the diversity of Fusarium species and the genes associated with their adaptation. Seven species were identified based on molecular markers and morphological analysis. The virulence assays showed that Fusarium asiaticum (Fa) and Fusarium graminearum (Fg) were the two major causal agents of FHB, with high virulence and more frequent isolates. Fungicide resistance analysis showed that four isolates had developed the resistance to carbendazim, and four isolates had developed the resistance to tebuconazole. Of note, two point-mutation variants (F200Y and E198Q) occurred in the β2-tubulin gene, leading to the carbendazim resistance. The landscape of genomic diversity was analyzed through whole-genome sequencing, revealing a total of 182,811 and 430,733 variants (including: single nucleotide polymorphisms, SNP, insertion and deletion, Indel, and structure variation, SV) among the Fa and Fg isolates, respectively. In addition, potential alterations in gene function (15.22%) were predicted among Fg variants. These alterations offer potential helps for the Fusarium species to adapt to various managements of FHB, which may increase risks in developing fungicide-resistant isolates. However, these annotated genetic variants are valuable resources for further genetic and genomic studies, as well as potential markers to assist disease risk assessment. [ABSTRACT FROM AUTHOR]

Adsorbed gas is an important component of shale gas. The methane adsorption capacity of shale determines the composition of shale gas. In this study, the methane adsorption capacity of marine, transitional, and lacustrine shales in the Sichuan Basin was analyzed through its isothermal adsorption, mineral composition, water content, etc. The results show that the methane adsorption capacity of marine (Qiongzhusi Formation and Longmaxi Formation), transitional (Longtan Formation), and lacustrine (Xujiahe Formation and Ziliujing Formation) shales is significantly different. The Longtan Formation has the strongest methane adsorption capacity. This is primarily related to its high organic matter and organic matter type III content. The methane adsorption capacity of the lacustrine shale was the weakest. This is primarily related to the low thermal evolution degree and the high content of water-bearing clay minerals. Smectite has the highest methane adsorption capacity of the clay minerals, due to its crystal structure. The water content has a significant effect on methane adsorption largely because water molecules occupy the adsorption site. Additionally, the temperature and pressure in a specific range significantly affect methane adsorption capacity. [ABSTRACT FROM AUTHOR]

In this study, we apply an agent-based modeling approach to understand individual visitors' multidestination travel patterns and the spatial spillover effects in visitor flows as an aggregate outcome. Based on previous literature, we specify three hypothetic visitor categories (global optimizers, sequential optimizers, and radial optimizers) according to visitors' attraction selection rules. We conduct an ABM simulation with a sample of 341 Chinese cities as destinations and 1,990 attractions to measure the degree of spillover between destinations by observing the frequency with which visitors traveling across destination boundaries visited attractions in other destinations. The simulation results demonstrate slightly different spillover effects based on visitor type and highlight three regions with particularly strong spillover effects: the Bohai Rim region, the Yangtze River Delta region, and the Sichuan and Chongqing region. These results appear consistent with those of exploratory spatial data analysis in a validation check. Lastly, policy implications are provided. [ABSTRACT FROM AUTHOR]

Rock destruction under high-temperature conditions is a key issue for nuclear waste treatment projects, underground coal gasification, and improvement of the use of geothermal energy for heating. Therefore, in this study, various methods and techniques were integrated to study the changes in mechanical properties, mineral composition, and microscopic fracture characteristics of Sichuan sandstone treated at 600°C. First, the fracture toughness and indirect tensile strength of untreated sandstones and high-temperature treated sandstones were tested by the MTS testing machine, and the double-K model (DKFM) was used to estimate the unstable fracture toughness. Then, the diffraction spectra of sandstone were analyzed with an X-ray diffractometer to determine the mineral composition change after heat treatment. Finally, the microscopic features of sandstone were observed through a scanning electron microscope (SEM) and optical microscope. The results show the following. (1) There is no significant change in the tensile strength and fracture toughness of Sichuan sandstone treated at 600°C. (2) The brittleness of Sichuan sandstone decreases and the ductility increases after high-temperature treatment. (3) The unstable fracture toughness value Kun obtained by the double-K model (DKFM) is significantly larger than the apparent fracture toughness value Kif. (4) After treatment at 600°C, the clay minerals in the sandstone changed significantly. Kaolinite is dehydroxylated to metakaolinite, which may increase the ductility of the rock. [ABSTRACT FROM AUTHOR]