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Nasopharyngeal carcinoma (NPC) is a malignant tumor originating in the nasopharyngeal epithelium with a high incidence in southern China and parts of Southeast Asia. The current treatment methods are mainly radiotherapy and chemotherapy. However, they often have side effects and are not suitable for long‐term exposure. Natural products have received more and more attention in cancer prevention and treatment because of their its high efficiency, low toxic side effects, and low toxicity. Natural products can serve as a viable alternative, and this study aimed to review the efficacy and mechanisms of natural products in the treatment of NPC by examining previous literature. Most natural products act by inhibiting cell proliferation, metastasis, inducing cell cycle arrest, and apoptosis. Although further research is needed to verify their effectiveness and safety, natural products can significantly improve the treatment of NPC. [ABSTRACT FROM AUTHOR]

There are various sedimentary structures developed in the black shales of the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation in Luzhou area, southern Sichuan Basin, southwestern China. In order to evaluate the controlling effects of sedimentary structures on the key parameters of shale reservoir properties, collected classification of sedimentary structures, scanning electron microscope observation, analysis of shale fabric and porosity characteristics, low‐pressure nitrogen adsorption, methane isothermal adsorption, and conventional triaxial compression test were carried out based on shale samples from Wells A‐H1, B‐H1, C‐H1 and D‐H1 in the study area. The sedimentary structures recorded in these shales are categorized into five types: homogeneous bedding, weak horizontal bedding, strong horizontal bedding, discontinuous ripple bedding, and gravel‐bearing massive bedding. In general, the palaeo‐hydrodynamics and oxygen content of water columns were weak when homogeneous bedding shale was deposited. The organic matter is the most abundant and the total organic carbon content is up to 4.01% on average. The average quartz content is 43.5%, and the brittleness index is the highest. The porosity and adsorption capacity were the highest, with an average of 4.57% and 79.5 scf/ton, respectively. Combined with its mechanical properties of low Poisson's ratio and high Young's modulus, homogeneous bedding sedimentary structure is associated with the shale units possessing the highest organic matter abundance, the strongest reservoir property, and the best fracability, which is the priority target for exploration and development of the Wufeng to lower Longmaxi Formation in the Sichuan Basin, southwestern China. [ABSTRACT FROM AUTHOR]

Questions: What are the characteristics of the spatial patterns of soil seed banks (SSBs) at local scales? How does the spatial distribution of SSBs relate to above‐ground vegetation? Location: The piedmont plain of the eastern slope of Gandur mountain, Wuhai, northwestern China. Methods: A plot of 50 m × 50 m square, divided into 100 quadrats (5 m × 5 m) and 100 subquadrats (1 m × 1 m), was prepared to conduct a field survey of vegetation and SSB sampling. We analyzed the spatial pattern of 196 samples at different scales and directions with geostatistical analysis. The relationship between above‐ground vegetation and SSB was quantified by integrating geostatistics, point pattern analysis, and spatial comparison (IGPS). Results: The SSB density in the study area was 404.5 ± 352 seeds·m−2. SSBs of shrub species and herbaceous species Ⅱ (occurring only below‐ground) had a moderate spatial autocorrelation, and their spatial dependence increased with increasing scale. The SSB of herbaceous species Ⅰ (occurring both above‐ground and below‐ground) had great spatial autocorrelation, and its spatial dependence showed an initial decrease and then increased. Furthermore, SSBs showed lower spatial heterogeneity in the prevailing wind direction than in other directions. The spatial patterns of SSBs of shrub species and herbaceous species Ⅰ correlated with shrubs within a specific range, but not with herbs, while the SSB of herbaceous species Ⅱ did not have a spatial relationship with above‐ground vegetation. Conclusion: The spatial pattern of SSBs had scale dependence features, which exhibited clustered distribution at a certain scale, and were significantly correlated with above‐ground shrubs. Therefore, we suggest subsampling larger quadrats with smaller sample units near shrubs in desert areas. Our workflow seems efficient for determining the spatial pattern of SSBs at medium small scale in arid areas. [ABSTRACT FROM AUTHOR]

The Upper Ordovician-Lower Silurian Longmaxi Shale in the Upper Yangtze block represents one of the most important shale gas plays in China. The shale composition, porosity, organic thermal maturity, and methane sorption were investigated at the Qilongcun section in the Dingshan area, southeastern Sichuan Basin. The results show that the Upper Ordovician-Lower Silurian Longmaxi Shale contains: (1) sapropelic I organic matter; (2) a 40-m thick bedded sequence where total organic carbon (TOC) content is > 2%; (3) a 30m thick layer at the base of the Longmaxi Shale with a brittle mineral content higher than 50%; and (4) a mean methane adsorption capacity of 1.80 cm3/g (7 MPa pressure). A positive correlation between TOC and sorbed gas indicates that organic matter content exerts an important control on methane storage capacity. Based on the analysis of the shale reservoir characteristics, the lower member of the Longmaxi Shale can thus be considered a favorable stratum for shale gas exploration and exploitation. It has similar reservoir characteristics with the Longmaxi Shale in the Jiaoshiba area tested with a high-yield industrial gas flow. However, based on tectonic analysis, differences in the level of industrial gas flow between the low-yield study area and the high-yield Jiaoshiba area may result from different tectonic preservation conditions. Evidence from these studies indicates the shale gas potential of the Longmaxi Shale is constrained by the reservoir and preservation conditions. [ABSTRACT FROM AUTHOR]