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Enhancing rural resilience is crucial due to the significant vulnerabilities faced by rural areas, such as weak economic foundations, scarce resources, and deficient infrastructure. This paper aims to provide a comprehensive review of rural network resilience (RNR) to underscore its importance in understanding the mechanisms and pathways of rural sustainable development. To establish the theoretical foundations of RNR, we trace the evolution of resilience concepts and their applications across disciplines. The proposed analytical framework integrates evaluation methods from network science to assess RNR's structural characteristics and outlines simulation techniques for predicting resilience under various risk scenarios. Furthermore, the paper examines the key influencing factors that shape RNR within complex rural regional systems, exploring the intricate evolutionary mechanisms involved. To bridge existing research gaps, a synergistic development perspective is introduced, emphasizing the interconnected, multi-layered nature of rural networks across societal, economic, and ecological domains. Additionally, a county-level analytical framework tailored for county-level rural resilience analysis is presented to offer strategic guidance for enhancing RNR and driving sustainable rural revitalization. This transdisciplinary synthesis propels RNR as an emerging field with significant policy implications. [ABSTRACT FROM AUTHOR]

During the Ediacaran–Cambrian transition, a series of stratal continuous and well-preserved siliceous rock and phosphorite assemblages developed in Qingzhen, Guizhou Province, China, facilitating research on the biological evolution, marine chemistry, and palaeoecological environment of this period. Therefore, we investigated the paleontology, trace and rare earth elements, total organic carbon, total sulfur content, and Zn isotopes of the phosphorus-bearing rock series in the Taozichong Formation of the Cambrian period in Qingzhen. Geochemical analysis reveals that the sedimentary rocks in this area were formed in the oxygen-rich seawater environment and were not affected by high-temperature hydrothermal activity. The upwelling ocean current provided abundant rare earth elements and other nutrient elements, as well as conditions for the prosperity of biota in Qingzhen. In addition, the δ66Zn value (−0.21‰–0.41‰ range and 0.17‰ mean) in the Qingzhen phosphorous rock series was much lower than that in seawater, indicating a strong level of biological productivity. The variation trend of δ13C, δ18O, and δ66Zn exhibited four stages and three obvious drift events. The results suggest that climate change during this period led to the intermittent flourishing and extinction of organisms, which triggered the negative drift of δ13C and δ18O in the ocean, resulting in a coordinated response of δ66Zn. The unique ecological environment of the Taozichong Formation in Qingzhen also provides favorable conditions for the population continuation of Ediacaran-type benthic soft-bodied metazoon dominated by discoid fossils, Shaanxilithes, worm fossils, and sponge fossils in the Cambrian strata, as well as participation in the global biological explosion events. The study area provides new insights for rebuilding the global Ediacaran–Cambrian ecosystem during the transition period. [ABSTRACT FROM AUTHOR]

Over the past few years, there has been significant research on applying Transformer models to time series prediction, yielding promising results. Simultaneously, researchers have begun exploring the utilization of Transformers for traffic prediction in order to mitigate the nonlinear spatial–temporal correlation inherent in traffic data. Some of these studies have attempted to characterize spatial–temporal features by incorporating embedding structures, with the goal of improving performance of the model. However, existing methods have not adequately addressed the issue of spatial–temporal correlation. To address these limitations, we propose the Transformer Network with Decoupled Spatial–Temporal Embedding (DSTET) model for traffic flow prediction. The key aspect of our model is its ability to effectively decouple the spatial and temporal embedding through the implementation of the Decoupled Spatial–Temporal Embedding structure. This structure enhances the characterization of spatial–temporal features, ultimately improving the performance of traffic prediction based on the Transformer model. Through experiments conducted on six real-world traffic datasets, our model consistently outperforms multiple baseline models, demonstrating its capability to address the identified problems. Moreover, we substantiate the efficacy of the suggested components via ablation experiments and furnish a thorough analysis of the attention weight matrix to clarify the functioning of the model. [ABSTRACT FROM AUTHOR]

Regional development issues can be reflected in land use and addressed through land use restructuring. It is commonly recognized that strengthening the role of small towns in the coordinated and sustainable development of counties, towns, and villages is effective in solving land use problems. However, relevant studies do not focus on the county space and lack scale extensions to reflect the role and status of small towns. In this paper, an analytical framework is developed and some research hypotheses are proposed from the perspective of "Scale-Space" interaction. Then, a county in central China is used as a case study to reveal the mechanism of rural land use restructuring by comparing the changes in land use structure in different locations in recent years. The study finds that under the constraint of the basic principle of "Requisition-Compensation Balance", the county has reorganized the spatial and landscape pattern of the countryside through extensive "demolition of the old" and "construction of the new". Among them, towns that are distant from the county center, while improving their cohesion, give full play to their role as regional sub-centers, and are expected to become an important force driving urbanization in the future. [ABSTRACT FROM AUTHOR]

Large infrastructure projects play a crucial role in regional development but can also negatively impact cultivated-land protection. This study focuses on the role of local governments in land-use conflicts and the rebalancing of land-use structures during large infrastructure construction. Using the construction of a reservoir in the Huaihe River as a case study, the research examines the evolution of government attention and the process of township local governments promoting land-use adjustment. The findings reveal that local governments go through a process of "Create–Reinforce–Adjust–Delivery" in their attention to reservoir construction to maximize their interests. Attention fluctuates in terms of reservoir construction, cultivated-land protection, and immigration-development assistance. Biased land-use decisions were made at different stages, leading to four stages of rebalancing efforts: "Generation–Challenge–Marked effect–Continuous negative impact". This process provides insights into land-use decision-making and the rebalancing of land-use structure. The study suggests that the superior government should guide local governments to enhance attention to cultivated-land protection through laws and policies, while local governments should focus on the quality protection of cultivated land and mitigate the negative impact of rebalancing efforts. [ABSTRACT FROM AUTHOR]

Accurate forecasting of traffic flow is crucial for intelligent traffic control and guidance. It is very challenging to forecast the traffic flow due to the high non‐linearity, complexity and dynamicity of the data. Most existing forecasting methods focus on designing complicated graph neural network architectures to capture the spatio‐temporal features of traffic data with the help of predefined graphs. However, traffic data exhibit a strong spatial dependency, which means that there are often complex correlations between nodes in a road network topology graph. Moreover, the spatial correlations of the road network change over time. To capture the properties of the road network topology graph, a novel spatio‐temporal adaptive graph convolutional networks model (STAGCN) based on deep learning is proposed. Utilize adaptive graph generation block to capture the static and dynamic structures of the traffic road network respectively, and they are integrated to construct an adaptive road network topology graph. Then the spatio‐temporal features of the traffic data are captured using spatio‐temporal convolution blocks. Experiments were conducted on publicly available traffic datasets for freeway traffic in California, USA, and the results showed that the prediction accuracy of the STAGCN model outperformed multiple baseline methods. [ABSTRACT FROM AUTHOR]

Karst bauxite is a major source of aluminum and contains high concentrations of trace elements such as Li, Ga, Sc, and rare earth elements (REEs). It is regarded as a potential non-conventional REE source due to the increasing demand for REEs. This study provides new mineralogical and geochemical evidence of a Lindai bauxite deposit in central Guizhou Province, aiming to analyze the genesis of REE minerals and reveal the forms of REEs occurring in these deposits. The results indicate that a large number of detrital and authigenic rare-earth phosphate minerals, including monazite and xenotime, were identified. In terms of their genesis, the authigenic monazite was mainly precipitated under alkaline and reducing conditions, whereas the authigenic xenotime was formed in acidic and reducing conditions. The mineralogical evidence detected by scanning electron microscopy with energy dispersive spectrometry (SEM-EDS) and a TESCAN Integrated Mineral Analyzer (TIMA) suggests that the REEs in the Lindai bauxite exhibit multiple forms, including rare-earth phosphate minerals (monazite and xenotime) and REE scavenging by hematite and anatase phases. Among them, the anatase controls some LREE (such as La, Ce, and Pr) distributions in addition to monazite, whereas the hematite also controls relatively large amounts of Sm, Eu, and HREE (such as Gd, Tb, Dy, Ho, Er, Tm, and Lu) distributions. According to the calculation of the percentage of REE-bearing mineral phases obtained by a TIMA analysis, REE scavenging by hematite accounted for 93.28% of all forms of REEs, REE scavenging by anatase accounted for 5.88%, monazite accounted for 0.67%, and xenotime accounted for 0.17%. This study provides new evidence of the forms of REEs occurring in Carboniferous karst bauxite in central Guizhou Province. [ABSTRACT FROM AUTHOR]

China's higher education has entered the stage of a universal system, enrolling over 50% of students, and the Chinese government takes its high-quality oriented development as its educational goal. However, as the largest developing country in the world, the regional inequality is still a major obstacle to the equitable development of higher education in China. With the 1270 higher education institutions listed by the Chinese Ministry of Education in 2021 as the research objects, the degree of regional inequality of higher education development (HED), and its influencing factors, was visualized after being calculated by geo-statistical methods, such as geographical detectors. The results show that, first, HED in China shows regional linkage and hierarchical connection in high-value regions in the input and outcome dimensions. Second, the input dimension is still the leading factor restricting current HED in China. At the local scale, the geographical stratification characteristics of the four dimensions are evident. The restriction of the educational process covers a wide range and is concentrated in areas with the high-value regions of HED. The innovation of the research is the analysis of the geographical stratification of mechanisms, which identifies regional differences in the factors affecting HED in China. [ABSTRACT FROM AUTHOR]

An active area of study under the dual carbon target, which is based on automatic identification systems (AIS), is the emission inventory of pollutants from ships. Data compression is required because there is currently so much data that it has become difficult to transmit, process, and store it. A trajectory simplification method considering the ship sailing state and acceleration rate of change is developed in this paper to assure the validity of the compressed data used in the emission inventory analysis. By carefully examining the integral relationship between acceleration and pollution emissions, the algorithm constructs an acceleration rate of change function for data compression and categorizes AIS data by ship navigation status. By dynamically altering the amount of acceleration change, the developed function can stabilize the pollutant emission calculation error and adaptively calculate the threshold value. The experimental results show that the emission calculation error of the proposed algorithm is only 0.185% when the compression rate is 90.28%. [ABSTRACT FROM AUTHOR]

Deprivation and dependence are the main signs of poverty, and elimination of both constitutes a major means of poverty alleviation. The foremost goal of China's targeted poverty alleviation strategy (TPAS) and the sustainable livelihood analysis framework (SLAF) was thus the elimination of deprivation and dependence. Together, TPAS and SLAF form a poverty alleviation mechanism that provides an opportunity to conduct a systematic analysis of TPAS implementation that achieved world‐renowned results in poverty alleviation. In this study, we comprehensively compare the changes in households and villages in a poor county before and after the implementation of TPAS; furthermore, we use a multilevel model to analyze the mechanism behind the functioning of the "Household‐Village" multilevel structure in the poverty alleviation process. The TPAS implemented a comprehensive livelihood system for poor households, whereby multidimensional deprivation was eliminated by supplementing livelihood capitals. Acquisition‐oriented assistance policies were offered to different groups to build customized paths of poverty alleviation, which ultimately helped poor households break through poverty and achieve sustainable livelihoods. This study highlights the close connection between the various components of the livelihood system, provides new research ideas for the study of China's TPAS and presents a reference template for the promotion of China's poverty alleviation programs. [ABSTRACT FROM AUTHOR]

DNA methyltransferase 3A (DNMT3A) has been regarded as a potential epigenetic target for the development of cancer therapeutics. A number of DNMT3A inhibitors have been reported, but most of them do not have good potency, high selectivity and/or low cytotoxicity. It has been suggested that a non-conserved region around the target recognition domain (TRD) loop is implicated in the DNMT3A activity under the allosteric regulation of the ATRX-DNMT3-DNMT3L (ADD) domain, but the molecular mechanism of the regulation of the TRD loop on the DNMT3A activity needs to be elucidated. In this study, based on the reported crystal structures, the dynamics of the TRD loop in different multimerization with/without the bound guest molecule, namely the ADD domain or the DNA molecule, was investigated using conventional molecular dynamics (MD) and umbrella sampling simulations. The simulation results illustrate that the TRD loop exhibits relatively higher flexibility than the other components in the whole catalytic domain (CD), which could be well stabilized into different local minima through the binding with either the ADD domain or the DNA molecule by forming tight hydrogen-bond and salt-bridge networks involving distinct residues. Moreover, the movement of the TRD loop away from the catalytic loop upon activation could be triggered simply by the detachment of the ADD domain, but not necessarily induced by the ADD domain relocation on the CD. All these dynamic structural details could be a supplement to the previously reported crystal structure, which underlines the importance of the structural flexibility for the critical residues in the TRD loop, arousing more interest in the rational design of novel DNMT3A inhibitors targeting this region. [ABSTRACT FROM AUTHOR]

In the process of ship's ocean transportation, the monitoring of crew's work completion is a very important part in the ship safety management, and using indoor positioning technology can improve the construction of ship management system. However, the current indoor positioning technology is not ideal in the engine room environment in the face of the complex electromagnetic environment and spatial structure. In order to improve the positioning accuracy, this paper proposes a Bluetooth indoor positioning strategy for ship cabin based on hierarchical area (BSSH) for deploying and dividing the regions requiring indoor positioning and combines Bluetooth Low Energy (BLE) with Bluetooth fingerprint positioning technology. Processing the fingerprint library by using region hierarchy and proximity classification algorithms to obtain reliable results in the ship environment, the results show that better Beacon deployment and hierarchical area algorithms can lead to a localization accuracy of 80.38%. [ABSTRACT FROM AUTHOR]

In ocean voyages, cabin indoor localization plays a considerably important role in ship safety management. Due to the special structure of ships and the influence of internal and external environment, the mainstream indoor positioning technology nowadays is not ideal for positioning inside the cabin. In order to improve the positioning accuracy, this article proposes an adaptive K -value-based cabin indoor positioning algorithm. The algorithm constructs a fingerprint library by collecting Received Signal Strength Indication data and carries out filtering; matches fingerprint information by adaptive K -values during the localization process, while using double K -nearest neighbor to reduce the influence of outlier points on the final localization; and finally uses the multi-point mass center method to determine the final localization results. The experimental results in the automated cabin laboratory show that the average positioning error of the algorithm is 1.74 m, which can well meet the cabin indoor positioning requirements. Graphical abstract [ABSTRACT FROM AUTHOR]

Structure-based drug design depends on the detailed knowledge of the three-dimensional (3D) structures of protein–ligand binding complexes, but accurate prediction of ligand-binding poses is still a major challenge for molecular docking due to deficiency of scoring functions (SFs) and ignorance of protein flexibility upon ligand binding. In this study, based on a cross-docking dataset dedicatedly constructed from the PDBbind database, we developed several XGBoost-trained classifiers to discriminate the near-native binding poses from decoys, and systematically assessed their performance with/without the involvement of the cross-docked poses in the training/test sets. The calculation results illustrate that using Extended Connectivity Interaction Features (ECIF), Vina energy terms and docking pose ranks as the features can achieve the best performance, according to the validation through the random splitting or refined-core splitting and the testing on the re-docked or cross-docked poses. Besides, it is found that, despite the significant decrease of the performance for the threefold clustered cross-validation, the inclusion of the Vina energy terms can effectively ensure the lower limit of the performance of the models and thus improve their generalization capability. Furthermore, our calculation results also highlight the importance of the incorporation of the cross-docked poses into the training of the SFs with wide application domain and high robustness for binding pose prediction. The source code and the newly-developed cross-docking datasets can be freely available at https://github.com/sc8668/ml%5fpose%5fprediction and https://zenodo.org/record/5525936, respectively, under an open-source license. We believe that our study may provide valuable guidance for the development and assessment of new machine learning-based SFs (MLSFs) for the predictions of protein–ligand binding poses. [ABSTRACT FROM AUTHOR]

Fossil plants from the carbonaceous shale of upper part of the Lower Carboniferous Jiujialu Formation in Lindai bauxite deposit fill a gap regarding the distribution of Early Carboniferous flora in Central Guizhou Province. Here the Lindai plant assemblage is systematically described, and its composition and geological age are discussed. Research demonstrates that 9 species in 6 genera of the fossil plants are discovered in this study, and they belong to lycopsids, sphenopsids and ferns, respectively. Based on the analysis of the floral composition, the geological age of the Lindai plant assemblage belongs to the Early Carboniferous Viséan. The discovery of Lindai plant assemblage not only provides a new fossil evidence to restrict the age of bauxite deposits in Lower Carboniferous Jiujialu Formation of Central Guizhou Province, but also has great significance to further research the palaeoecological setting and floral evolution during the Early Carboniferous. [ABSTRACT FROM AUTHOR]

The identification and optimization of lead compounds are inalienable components in drug design and discovery pipelines. As a powerful computational approach for the identification of hits with novel structural scaffolds, structure-based virtual screening (SBVS) has exhibited a remarkably increasing influence in the early stages of drug discovery. During the past decade, a variety of techniques and algorithms have been proposed and tested with different purposes in the scope of SBVS. Although SBVS has been a common and proven technology, it still shows some challenges and problems that are needed to be addressed, where the negative influence regardless of protein flexibility and the inaccurate prediction of binding affinity are the two major challenges. Here, focusing on these difficulties, we summarize a series of combined strategies or workflows developed by our group and others. Furthermore, several representative successful applications from recent publications are also discussed to demonstrate the effectiveness of the combined SBVS strategies in drug discovery campaigns. [ABSTRACT FROM AUTHOR]

The Zunyi manganese deposits, which formed during the Middle to Late Permian period and are located in northern Guizhou and adjacent areas, are the core area of a series of large‐medium scale manganese enrichment minerogenesis in the southern margin and interior of the Yangtze platform, Southern China. This study reports the universal enrichment of rare earth elements (REEs) in Zunyi manganese deposits and examines the enrichment characteristics, metallogenic environment and genesis of REEs. The manganese ore bodies present stratiform or stratoid in shape, hosted in the silicon–mud–limestones of the Late Permian Maokou Formation. The manganese ores generally present lamellar, massive, banded and brecciated structures, and mainly consist of rhodochrosite, ropperite, tetalite, capillitite, as well as contains paragenetic gangue minerals including pyrite, chalcopyrite, rutile, barite, tuffaceous clay rock, etc. The manganese ores have higher ΣREE contents range from 158 to 1138.9 ppm (average 509.54 ppm). In addition, the ΣREE contents of tuffaceous clay rock in ore beds vary from 1032.2 to 1824.5 ppm (average 1396.42 ppm). The REEs from manganese deposits are characterized by La, Ce, Nd and Y enriched, and existing in the form of independent minerals (e.g., monazite and xenotime), indicating Zunyi manganese deposits enriched in light rare earth elements (LREE). The Ceanom ratios (average –0.13) and lithofacies and paleogeography characteristics indicate that Zunyi manganese deposits were formed in a weak oxidation‐reduction environment. The (La/Yb)ch, Y/Ho, (La/Nd)N, (Dy/Yb)N, Ce/Ce* and Eu/Eu* values of samples from the Zunyi manganese deposits are 5.53–56.92, 18–39, 1.42–3.15, 0.55–2.20, 0.21–1.76 and 0.48–0.86, respectively, indicating a hydrothermal origin for the manganese mineralization and REEs enrichment. The (δ13CV‐PDB (−0.54 to −18.1%) and (δ18OSMOW (21.6 to 26.0%) characteristics of manganese ores reveal a mixed source of magmatic and organic matter. Moreover, the manganese ore, tuffaceous clay rock and Emeishan basalt have extremely similar REE fractionation characteristic, suggesting REEs enrichment and manganese mineralization have been mainly origin from hydrothermal fluids. [ABSTRACT FROM AUTHOR]

The study of multi-dimensional expansion of urban space (MEUS) addresses the laws of urban spatial expansion from all directions and angles. Using Nanjing as an example, this paper constructs multi-temporal, urban three-dimensional models based on RS and GIS technology and then conducts qualitative and quantitative analysis of MEUS using plot ratio change maps and MEUS quantitative index for built-up areas. Based especially on the concept of volume growth contribution rate, this paper analyzes the characteristics of MEUS in different stages. The results show that in 2000–2004, planar expansion played the main role, the internal potential development (IPD) intensity of the urban built-up areas was relatively large, and the volume growth contribution rate was low; in 2004–2008, planar expansion accelerated, and IPD slowed down; in 2008–2012, planar expansion slowed while IPD intensity increased; the contribution rates of volume growth of urban IPD for the three periods were 22.21%, 24.51% and 73.38%, respectively. This study expands the research perspective of urban spatial expansion, and the adopted methods are instructive and meaningful for MEUS research. In addition, the results of this study will deepen the understanding of MEUS laws and help improve scientific decision-making for urban planning and urban land use management. [ABSTRACT FROM AUTHOR]

In this paper, the artificial neural network (ANN) model was used to evaluate the degree of intensive urban land use in Nanjing City, China. The construction and application of the ANN model took into account the comprehensive, spatial and complex nature of urban land use. Through a preliminary calculation of the degree of intensive land use of the sample area, representative sample area selection and using the back propagation neural network model to train, the intensive land use level of each evaluation unit is finally determined in the study area. Results show that the method can effectively correct the errors caused by the limitations of the model itself and the determination of the ideal value and weights when the multifactor comprehensive evaluation is used alone. The ANN model can make the evaluation results more objective and practical. The evaluation results show a tendency of decreasing land use intensity from the core urban area to the periphery and the industrial functional area has relatively low land use intensity compared with other functional areas. Based on the evaluation results, some suggestions are put forward, such as transforming the mode of urban spatial expansion, strengthening the integration and potential exploitation of the land in the urban built-up area, and strengthening the control of the construction intensity of protected areas. [ABSTRACT FROM AUTHOR]

Stratiform baryte deposits are widespread in Cambrian and Devonian strata in China and around the world. In this article, the authors studied the sulfur isotopic features and forming mechanism of the stratiform baryte deposits occurring within the Upper Devonian cherts of the Zhenning-Ziyun county, Guizhou province, located in the Southwestern margin of the Yangtze Platform. The sulfur isotopic data from 18 baryte ore samples of the Leji section of Zhenning county are presented herein with values that range from +41.9‰ to +68.4‰ (AVG = +59.9‰). The δ34S values of the baryte ore from the Mohao section of Ziyun county are stable and show a narrow range from +41.3‰ to +47.0‰ (AVG = +44.0‰). In the Luocheng section of Ziyun county, the δ34S values of the baryte ore vary from +27.6‰ to +36.4‰ (AVG = +32.7‰). The δ34S values of all samples are higher than those of the coeval seawater sulfates (+25‰). The scanning electron microscope analysis indicates that spherical, dumbbell-shaped, clavate bacterial and bacteria-like fossils were observed, as well as the irregular schistose and framboid forms of Fe oxides that occur around the surfaces of baryte grains and inter-grains. Fe oxides take irregular schistose and framboid forms. These findings imply the significant concentration of heavy sulfur related to the seawater sulfates with the action of bacterial sulfate reduction in a closed basin. In addition, the trend of the δ34S value of baryte ores is gradually decreasing from the Leji to Mohao and Luocheng sections, which suggests that Leji area is located in the deepwater area of the restricted rift basin, and in a more closed depositional environment. [ABSTRACT FROM PUBLISHER]

The Leishan-Rongjiang antimony ore field (LAOF) is in a unique geotectonic location in the uplift between the Youjiang and Xiangzhong basins. This paper focuses on two representative deposits in the LAOF: the Bameng and Peize antimony (Sb) deposits. We analyzed fluid inclusions (FIs) in stibnite and coexisting quartz, as well as the sulfur isotopic composition of stibnite, to better understand the nature of the ore-forming fluid and the metallogenic process. The FIs data from samples of the stibnite and coexisting quartz indicate that the ore-forming fluids were characterized by low-temperature (150-210 °C), low-salinity (1.5 wt%-6.0 wt% NaCl equiv.), and low-density (0.872-0.961 g/cm). The δS values of stibnite (−8.21‰ to 3.76‰, average = −6.30‰) fall in between the sulfur isotopic compositions of the mantle and of biogenic sulfur in sedimentary rocks. However, the δS values (−4.41‰ to +0.04‰, average = −2.49‰) of the ore-forming fluids are generally closer to the sulfur isotopic composition of the mantle source, indicating that the sulfur in the LAOF was mainly sourced from the mantle, but with possible involvement of biogenic sulfur. In addition, FIs petrography and ore deposit geology show that fluid boiling resulted from an abrupt decrease in pressure, which may have triggered the precipitation of stibnite. We conclude that low-temperature, dilute hydrothermal fluids with mixed origins migrated along the regional fault and interacted with the wall rock, extracting the ore-forming materials. Then, the ore-forming fluids were injected into the fault fracture zones. [ABSTRACT FROM AUTHOR]

Urbanization reflects the overall behavior of human society; thus, characterization of its associated spatial and temporal trends has been extensively researched. This study examines the process of urban expansion in the Huaihe River Basin (HRB) which is a key transition region within China’s urban system. In order to grasp the urban expansion process in different temporal sequences objectively, rapidly, and accurately, we used remote sensing data to assess the urban expansion in time and space. Urban expansion rules were defined for the urban area, urbanization intensification, extended dynamic degree, and spatial pattern. The research findings show that the urban area expansion speed was at medium level throughout the entire HRB and within each province. Presently, the formation of a whole urban agglomeration or urban system is not complete in the HRB; urban expansion in the HRB displayed space-time disequilibrium tendencies during 1998–2013. [ABSTRACT FROM AUTHOR]

Iodine was relatively enriched in the sedimentary phosphorite that formed during the Doushantuo period of Late Ediacaran, South China, especially in the Central of Guizhou Province, Southwest China. The resources of the associated iodine in the phosphorite are extremely high. The analysis and test of elements such as iodine in the phosphorus-bearing rock series reveal that iodine occurs only in the phosphorite and the iodine has positive correlation with PO and CaO which are the main components of apatite, while has negative correlation with major oxides including MgO, NaO, FeO, TiO and KO, which showed that the iodine is mainly rich in phosphorite. Meanwhile, it was observed that the iodine content is the highest in the gray-white clastic phosphorite, but is relatively low in the gray-black carbonaceous phosphorite. Discussion of the sedimentary environment in the research area showed that the gray, gray-white nest-like, particle-like, and fragmental algae-enriched phosphorite feature the most abundant iodine element, with the average content of 59 mg kg and the maximum value of 98 mg kg. The compacted blocky phosphorite deposited in the neritic marine basin facies only has trace iodine, maybe due to the impact on the iodine absorption caused by the inhibition of algae propagation under anaerobic and reduction conditions. Results of correlation analysis illustrate that the relationship between iodine and the number of algae was suggested. Based on the aforementioned regulations and conditions for the iodine concentration in the phosphorite of the Late Edicanran Doushantuoian, the main iodine-enriched of ore, ore type, and facies belt were considered biogenic apatite, clastic phosphorite, and neritic marine platform facies, respectively. [ABSTRACT FROM AUTHOR]

In the study of the phosphate-bearing stratum at the bottom of the Cambrian system, the authors found that there occurred carbon isotope negative anomalies in the Taozichong section phosphate-bearing stratum in Qingzhen, Guizhou Province; they can be correspondingly compared with other synsedimentary carbon isotope negative anomalies both at home and abroad. The results showed that there occurred three negative anomalies of carbon isotopes in the Neoproterozoic-Early Cambrian Taozichong Formation, indicating that the temporal palaeo-oceanographical environment changed significantly, in which there happened two times of intensive carbon isotope variation, corresponding to creature extinction. Meanwhile, it is believed that the carbon isotope negative anomalies in phosphorites were caused by the ascending water mass of ocean current with the negative carbon isotopic composition of deep-ocean hydrothermal deposits. [ABSTRACT FROM AUTHOR]

The evolution of the global sulfur isotope curve was plotted based on the δ 34S values of evaporates resultant from oceanic evaporation. In the long period of geological history the δ 34S values showed obvious peaks for three times during the process of ancient oceans’ sulfur isotope evolution, namely the Early Cambrian (+30‰), the Late Devonian (+25‰) and the Permian-Triassic transition interval (+17‰), but the causes of the abnormal rise of sulfur isotopic values during the geological period are still in question. In this paper, 18 samples collected from a large Devonian barite deposit from Zhenning County were analyzed to determine their δ 34S values, revealing that the 18 samples have very high δ 34S values (δ 34S=41.88‰–+68.39‰), with an average close to 56.30‰, which are higher than the isotopic values of contemporary sulfates (+17‰–+25‰). A comparative analysis was conducted of the emerging of high δ 34S barite deposits (from Cambrian and Devonian) and the δ 34S variation curves of the ancient oceans. The results indicate that the time when the obvious peaks of δ 34S values appeared and the time of massive sedimentation of high δ 34S barite deposits are very close to each other, which, in our opinion, is not a coincidence. There may exist some correlations between the sulfur isotope evolution of ancient oceans during the diverse periods of geological history and the massive sedimentation of high δ 34S barite deposits. Therefore, it is inferred that perhaps it was the massive sedimentation of high δ 34S barites that caused the sharp rise of δ 34S values in a short period of time. [ABSTRACT FROM AUTHOR]

Eight phenyl imidazolinone derivatives were synthesized from N2-(2,4-dimethylphenyl)-N1-methyformamidine (DPMF) via scaffold-hopping method using the ring-closure approach. The prepared compounds were verified using 1H and 13C NMR and HRMS spectroscopies. The structure of compound 3c was confirmed by single-crystal X-ray diffraction analysis. The mean plane of the phenyl and imidazolinone moieties was almost coplanar with an angle of 8.85(4)°. In the crystal, molecules were interlinked with intermolecular hydrogen bonds (N–H···O and C–H···O), generating a network structure. Additionally, compound 3f displayed the highest insecticidal activity (86.7%) against Plutella xylostella at 600 mg/L, which was significantly higher than the insecticidal activity (23.0%) of DPMF. Also, compound 3d displayed good fungicidal activities against Phytophthora capsici, Phytophthora sojae, and Phytophthora infestans. Density functional theory (DFT) calculations were performed to explain the insecticidal and fungicidal activities of phenyl imidazolidin-2-one derivatives, especially potent compounds 3f and 3d. Moreover, the binding modes of compounds 3a–h and DPMF against octopamine receptor of Plutella xylostella were studied by homology modeling and molecular docking. Therefore, a preliminary structure–activity relationship (SAR) was derived and discussed. These results encourage the exploration of novel insecticides and fungicides based on DPMF. [ABSTRACT FROM AUTHOR]

The Nibao gold deposit, which includes both fault-controlled and strata-bound gold orebodies, constitutes an important part of the Yunnan–Guizhou–Guangxi "Golden Triangle" region. Defining the mineralization age of these gold orebodies may provide additional evidence for constraining the formation ages of low-temperature orebodies and their metallogenic distribution in South China. Petrographic studies of gold-bearing pyrites and ore-related quartz veins indicate that these pyrites coexist with quartz or filled in vein-like quartz, which suggests a possible genetic relationship between the two from Nibao gold deposit. Minerals chemistry shows that Rb and Sr are usually hosted in fluid inclusions in quartz ranging from 0.0786 to 2.0760 ppm and 0.1703 to 2.1820 ppm, respectively. The Rb–Sr isotopic composition of gold-bearing quartz-hosted fluid inclusions from the Nibao gold deposit were found to have Rb–Sr isochron ages of 142 ± 3 and 141 ± 2 Ma for both fault-controlled and strata-bound orebodies, respectively, adding more evidence to previous studies and thus revealing a regional gold mineralization age of 148–134 Ma. These results also confirm the Middle-Late Yanshanian mineralizing events of Carlin-type gold deposits in Yunnan, Guizhou, and Guangxi Provinces of Southwest China. In addition, previous studies indicated that antimony deposits in the region which were formed at ca. 148–126 Ma have a close affinity with gold deposits. This illustrates that the regional low-temperature hydrothermal gold mineralization is related in space and time to the Yanshanian (ca. 146–115 Ma) magmatic activity. Specifically, the large-scale gold and antimony mineralization are considered to be inherently related to mantle-derived mafic and ultramafic magmatic rocks associated with an extensional tectonic environment. Based on the initial 87Sr/86Sr ratios of 0.70844 ± 0.00022 (2σ) and 0.70862 ± 0.00020 (2σ) for gold-bearing quartz veins from fault-controlled and strata-bound gold orebodies, respectively, at the Nibao gold deposit, as well as the C, H, O, and S isotopic characteristics of gold deposits located in the Golden Triangle region, we suggest that the mantle-derived material can be involved in the formation of the Nibao gold deposit and that the ore-forming fluid can be derived from a mixed crust–mantle source. [ABSTRACT FROM AUTHOR]

The article focuses on a study that investigates geochemistry characteristics of Nibao super large gold deposits from Guizhou Province, China and its geologic significance. The study reveals that hydrothermal precipitation prompted the initial formation of Nibao gold deposits and subsequent low-temperature hydrothermal processes resulted in gold remobilization in ore-forming materials. Also the study shows that the Nibao gold deposits have sedimentary hydrothermal alteration characteristics.

The article presents a study to investigate the ZhuXi vanadium deposit from eastern Guizhou, China by using sedimentology, trace element geochemistry and isotope geochemistry. Topics discussed include carbon isotope value of vanadium, trace element geochemical characteristics of vanadium ore, and rare earth elements content in vanadium ore. Other topics discussed include distribution of vanadium ore in sandstone, siltstone, and silty mudstone.