In order to clarify the development characteristics of the Paleogene fault system in Baiyun Sag and deepen the study of sag structure under the ternary coupling control of "preexisting structure, detachment thinning and magmatic intrusion", in this paper, we use the high precision 3D seismic data in depth domain, combined with the methods of structural style identification, quantitative characterization of fault activity and balanced profile evolution to carry out multidimensional research on fault classification, dominant orientation, ordered activity and three-dimensional evolution. The research shows that: (1) There are four levels of faults in Baiyun Sag, including the faults in first-level controlled basin, second-level controlled depression, third-level controlled structural belt and fourth-level controlled trap. There are three dominant directions: NEE, EW and NW. (2) The structural characteristics of Baiyun Sag are significantly different in the west, middle and east. The western part is dominated by high-angle shovel-type depression-controlled faults with two stages and four groups of magmatic intrusion. The central area is characterized by medium-high Angle shovel or seat depression-controlled faults, which can converge with the Moho surface in depth. The eastern area is characterized by the development of gently wave-like low-angle detachment faults, which are invaded by the magma of 2-3 periods, and is a typical "Uplift alternated with depression" structure. (3) There are great differences in activity intensity and activity time among faults of different grades in Baiyun Sag. The controlling effect of faults on deposition appears also as a certain time series. The orderly activity of faults controls the structural evolution and the migration of subsidence center in Baiyun Sag. (4) The Paleogene in Baiyun Sag has undergone five main tectonic evolution stages, namely, initial rifting stage, detachment rifting stage, bottom intrusion rifting stage, fault-depression transition stage and depression stage. Since the Middle Eocene, the structure of Baiyun sag has been transformed from "South fault and north overlying" to "North and south double fault".

Elucidating how the built environment influences urban vitality at the micro-scale is crucial for precisely guiding the implementation direction of refined urban planning in the context of urban renewal on existing land. However, most existing studies have often overlooked the differential mechanisms and nonlinear relationships of the built environment's impact on urban vitality at the micro-scale. This paper takes the central urban area of Xi'an City as the study area, employs multi-source data, and integrates machine learning algorithms with the Shapley Additive Explanations (SHAP) interpretability method at the street and block levels to explore the nonlinear effects of the built environment on urban vitality. The results indicate that: (1) The spatial distribution characteristics of urban vitality in the central urban area of Xi'an City are generally similar at the street and block levels, exhibiting a gradient pattern of decreasing vitality from the center to the periphery. There are slight differences in the distribution of vitality hotspots between the street and block levels, indicating spatial heterogeneity. (2) Among the built environment elements that affect the urban vitality of the central urban area of Xi'an City, global integration makes the highest relative contribution at the street level, whereas at the block level, the number of POI categories is the most influential. (3) The built environment exerts a nonlinear influence on urban vitality in the central urban area of Xi'an City. Among the common core elements affecting the vitality of streets and blocks, factors such as sky openness and subway accessibility exhibit fundamentally consistent threshold effects at both the street and block levels. Conversely, factors like the number of POI categories, floor area ratio, and green visual index show varying effects at these two levels. Built environment factors exert an interactive influence on urban vitality. At the street level, subway accessibility is the dominant element, while at the block level, it is the number of POI categories. Based on these findings, relevant planning suggestions are proposed to enhance the interaction and coordinated development between streets and blocks and to improve urban vitality.

Tourism carries the people's yearning for better life, and the development of county-level tourism has gradually become an important starting point and effective path to promote urban-rural integration, help construction of beautiful China and promote common prosperity. Utilizing the nearest neighbor index, kernel density estimation, gravity model, bivariate spatial autocorrelation, and binary logistic regression, an analysis was conducted on the spatial and temporal distribution of China's top 100 counties in tourism, as well as the correlation factors influencing their advancement and retreat patterns. The data utilized in this research encompassed the panel data of China's top 100 tourism counties spanning from 2019 to 2023. It reveals that: (1) The spatial distribution of the top 100 tourism counties appears "more in the east and fewer in the west," gradually forming a dual-core agglomeration pattern centered around the "one main (Yangtze River Delta) and one secondary (Sichuan-Guizhou)" regions. (2) Various correlation factors, including natural environmental conditions, socio-economic factors, and policy planning, jointly impact the distribution of the top 100 tourism counties. (3) In terms of formation mechanism, tourism resources, geographical agglomeration, economic scale and industrial structure have a significant impact on the pattern of advance and retreat of the top 100 tourism counties.

Based on the data of 41 cities in the Yangtze River Delta from 2008 to 2019, this paper constructs Poisson model and negative binomial model to evaluate the impact of land and business environment on the location of new digital enterprises. The empirical results show that the level of business environment plays a significant role in location choic of new digital enterprises, while the single low-price industrial land strategy is ineffective in attracting digital enterprises. With the improvement of the business environment, the strategy of selling industrial land at a low price still has a driving effect on new digital enterprises. The level of business environment has a negative spatial spillover effect on the location of new enterprises. Compared to the "low price competition" strategy, the business environment is more attractive to digital enterprises, and a reasonable land price can attract enterprises to enter.

To study the air quality and changes in the classroom, in the spring semester, the air quality of a university in Shaoxing (duration of 100 min, with population density of 0.32~0.39 m^-2) was tested and intervened. The environmental data were recorded every 5 minutes, including indoor and outdoor temperature, relative humidity and CO₂ concentration. The volatile organic compounds (VOCs) were sampled and the indoor air quality was evaluated. The field measurement results showed that the average indoor temperature in the classroom was 17.8~29.2 ℃, the average indoor relative humidity was 34.5%~91.0%, and the average concentrations of CO₂ and total volatile organic compounds (TVOC) were 921.6×10^-6~1 805.2×10^-6 and 330×10^-9~682×10^-9, respectively. The intervention experiment showed that the satisfaction and acceptability of the respondents (graduate students) with air quality were significantly reduced when the CO₂ volume concentration reached 2 296×10^-6. Within the temperature range of 17~31 ℃, the CO₂ emission rate of human body increases by 0.56 L·h^-1 with every 1 ℃ increase in temperature. In order to maintain the indoor CO₂ concentration at 1 000×10^-6, the per capita ventilation rate needs to be increased by 0.25 L·s^-1.

The study of particle motion in relativistic state and the Born-Infeld model in nonlinear electrodynamics theory are directly related to a class of Dirichlet problem of mean curvature equation in Minkowski space. In this paper, we use the bifurcation method to study the existence of \mathrm{\epsilon }-shaped connected component of positive solutions for such problems, and thus obtain the existence and multiplicity of the corresponding positive solutions. The conclusions generalize and improve the related results of the existing work.

The n-dimensional hyperbolic-parabolic coupled equations from thermalelasticity were studied, and the large time asymptotic property of their solutions were characterized. First, a special diagonalization procedure was used to obtain the asymptotic expressions for the energy. Subsequently, the large time decay estimates of this energy and its asymptotic profile were obtained by using the WKB analysis and the Fourier analysis.

This paper primarily investigates the efficient numerical approximation of a coupled system of Navier-Stokes equations and the elastic bending energy model of lipid vesicles. To accurately and effectively solve this complex system, a fully decoupled, linear, second-order time-accurate method based on the time-dependent auxiliary variable approach is proposed. The pressure projection method is employed to decouple the computation of the velocity field and pressure field in the Navier-Stokes equations. The detailed implementation of the algorithm is presented in this paper, and the energy stability and uniqueness of the discrete scheme are rigorously proved theoretically. To further enforce the consistency between the original energy and the modified energy, a simple and effective energy correction technique is introduced. The accuracy and energy stability of the proposed numerical scheme are validated through two-dimensional numerical experiments.

This study utilizes the fifth-generation reanalysis data (ERA5) from the European Centre for Medium-Range Weather Forecasts (ECMWF) to investigate the vertical transport characteristics of ozone over the Qinghai-Tibet Plateau across different seasons and their impact on ozone distribution. Through statistical and composite analysis methods, the results indicate that in summer, ozone over the plateau primarily exhibits an upward transport pattern, with a vertical flux of approximately 1×10?⁹ kg·m?2·s?1. In winter, the transport direction reverses, showing a downward transport from the stratosphere to the near-surface, with a flux of about 3×10?⁹ kg·m?2·s?1. Spatially, in summer, ozone concentration at the same altitude increases gradually with latitude. In winter, ozone concentration increases with latitude above 300 hPa, whereas below 300 hPa, it exhibits the opposite trend. Regarding seasonal variations, from summer to winter, the high ozone concentration region shrinks and shifts southward. Furthermore, this study reveals that the downward vertical transport of ozone in winter is a key mechanism leading to the south-high, north-low distribution of tropospheric ozone over the plateau, while the upward transport of low-concentration ozone in summer is a critical factor contributing to the ozone valley in this region. These findings provide important scientific insights into the spatiotemporal distribution of ozone over the Qinghai-Tibet Plateau and its underlying dynamical mechanisms.

The Qiantang River has received the attentions of many researchers. A large number of organic micropollutants have been detected, which may cause physiological, biochemical, and toxicological effects in aquatic organisms and threaten ecological conditions and human health. However, studies on the human-derived aromatic hydrocarbon receptor (AhR) effects of organic micropollutants in surface waters of the Qiantang River are still limited. This study was conducted to explore the pollution status of organic micropollutants in the surface water of Hangzhou section of Qiantang River through target chemistry, in vitro bioassay, and the toxicity contribution of AhR effects based on the iceberg model, in order to assess the toxicity risk of surface water of Qiantang River to AhR effects from human sources. Targeted chemical analysis detected four categories of organic micropollutants∶ pesticides, phthalates, perfluorinated compounds and polycyclic aromatic hydrocarbons. The results of chemical analysis showed that the average concentration of perfluorinated compounds was 109.52 ng?L^-1, which was the highest cumulative concentration of pollutants detected at each site, and its cumulative concentration ranged from 219.02 to 3 645.54 ng?L^-1. In particular, perfluorooctanoic acid (PFOA) is the main pollutant found in perfluorinated compounds in this study. In vitro bioassays showed a dose-dependent increase in the level of transcriptional activity of human-derived AhR receptors with strong transcriptional activity. Particularly, the transcriptional activity level of Fuchun River (80 REF) was 21.53 times higher than that of the blank control group, and Puyang River and Qibao had already shown significant AhR effects under the condition of no enrichment. The equivalent concentration range of the AhR effect in surface water extracts from Qiantang River was 17.61~46.17 ng?L^-1B[a]P-EQ, which was higher than the limit value of 4.20 ng?L^-1B[a]P-EQ for surface water proposed by the European Union Water Framework Directive. Calculation of the toxicity contribution ratio showed that the main contribution was from polycyclic aromatic hydrocarbons (37.03%~88.15%), followed by pesticides (5.08%~14.30%), and phthalates (2.62%~9.21%). Chrysene (Chr) was the major contributor to AhR mediated activity, followed by benzo[a]anthracene (BaA) and benzo[b]fluoranthene (BbF). In conclusion, the data in this article showed that surface water extracts from the Qiantang River significantly activated the AhR effect. This study provides new insights into the toxic effects of mixed pollutants and human health risk assessment.

In this paper, seven species of Carex are newly reported for provincial distribution of China. C. alterniflora is newly recorded from Anhui province, and C. speciosa and C. pergracilis are newly recorded from Guizhou province. C. wuyishanensis and C. borealifujianica are newly recorded from Zhejiang province. C. wuyishanensis, C. aequialta and C. jinfoshanensis are newly recorded from Hunan province. In Flora of Zhejiang (Vol 7), C. tianmushanica was mis-identified as C. kiangsuensis, whereas the specimens of C. kiangsuensis collected from Mt. Kuocang in Linhai was mis-identified as C. pisiformis. C. dolichostachya, a species distributed in China's Taiwan and Japan, was mis-identified in the Chinese mainland. The specimens from Zhejiang should be identified as C. foraminatiformis. Cyperus eragrotis, a naturalized species of the family Cyperaceae, was discovered from Zhejiang during the botanical survey of wetlands and is newly recorded in China VI.

The plants of the genus Rubus (Rosaceae) are economically important as fruit crops, medicines and ornamental plants. During the course of identifying the specimens of Rubus in Sichuan province, two species and two varieties, namely R. amabilis var. microcarpus, R. delavayi, R. inopertus var. echinocalyx and R. reflexus, were discovered as new distribution records in Sichuan province. R. reflexus var. hui is treated as a synonym of R. reflexus var. reflexus. The discovery of these new records enriches the germplasm resources of Sichuan province and provides the basic information for the compilation of Flora of Sichuan and for the study on inventory of plant diversity in Sichuan province.