Central China Region Research Articles

Genetically- and environmentally-dependent processes drive interspecific and intraspecific divergence in the Chinese relict endemic genus Dipteronia

China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere. Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of central and south-western China allowed their persistence through the late Neogene climate fluctuations. One of these relict lineages is Dipteronia, an oligotypic tree genus with a fossil record extending to the Paleocene. Here, we investigated the genetic variability, demographic dynamics and diversification patterns of the two currently recognized Dipteronia species (Dipteroniasinensis and D.dyeriana). Molecular data were obtained from 45 populations of Dipteronia by genotyping three cpDNA regions, two single copy nuclear genes and 15 simple sequence repeat loci. The genetic study was combined with niche comparison analyses on the environmental space, ecological niche modeling, and landscape connectivity analysis. We found that the two Dipteronia species have highly diverged both in genetic and ecological terms. Despite the incipient speciation processes that can be observed in D. sinensis, the occurrence of long-term stable refugia and, particularly, a dispersal corridor along Daba Shan-west Qinling, likely ensured its genetic and ecological integrity to date. Our study will not only help us to understand how populations of Dipteronia species responded to the tectonic and climatic changes of the Cenozoic, but also provide insight into how Arcto-Tertiary relict plants in East Asia survived, evolved, and diversified.

May–June relative humidity variation recorded by tree ring widths of Pinus armandii Franch since 1863 in the Funiu Mountains, central China

Long-lasting drought records can provide valuable insights into the history of hydroclimate change in central China, but meteorological records are too short to capture long-term variability of the humidity. In this study, we established a tree-ring width chronology of Pinus armandii Franch in the Funiu Mountains region of central China. Correlation analyses showed that tree radial growths were mainly limited by hydrothermal combination in May–June. The results of the moving correlation analysis further showed that the response relationship between tree growth and relative humidity in May–June (RHMJ) was the most stable. This relationship has been reconstructed since 1863. The variance of the reconstructed RHMJ was explained by 41.7% (40.6% after adjusting for degrees of freedom). Over the past 158 years, there were 3 wet periods and 4 dry periods. The spectral analysis revealed that the reconstructed RHMJ exhibited quasi-periods of 2-4a and 31.6a, and cross-spectrum analysis showed that the reconstructed RHMJ may be related to ENSO, PDO, solar activity and the East Asian summer monsoon. The spatial correlation analysis revealed that the reconstructed RHMJ accurately depicted the fluctuations in humidity within the Huanghe-Huaihe Plain. Furthermore, the reconstructed RHMJ exhibited a strong negative correlation with the sea surface temperature (SST) of the subtropical North Pacific, while it displayed a highly significant positive correlation with the SST of the eastern equatorial Pacific from the previous May to the current April. This also indicated a possible link between humidity fluctuations in the Huanghe-Huaihe Plain and the Pacific internal variability in climate system. Therefore, this research aims to expand and complement the existing meteorological records, providing important reference significance for forest management, agriculture, and animal husbandry.

Work status among middle-aged and older individuals in China: the effects on physical and mental health.

China's middle-aged and older population is a rich source of human capital. Therefore, considering the health of this group is important when creating and using human resources. Using data from the nationwide China Health and Retirement Longitudinal Study (CHARLS) 2018 baseline survey of 19,000 adults ages 45 years and older, this study was an objective investigation of the effects of work on the physical and mental health of middle-aged and older adults. We conducted several types of analyses using details of participants' lifestyles and demographic characteristics (living environment, education, financial level, and access to medical services) with work (i.e., employment or volunteer work) as a primary input component of health production to examine their effects on the health status of middle-aged and older individuals. Six primary outcomes were identified: (1) Employment positively affects both the physical and mental health of middle-aged and older people; (2) Employment can influence the physical and mental health of middle-aged and older people through income, cognitive level, and social support networks; (3) Compared to non-self-employment, self-employment dramatically worsens physical health but has no apparent detrimental effects on mental health. Compared to non-agricultural employment, agricultural labor affects both physical and mental health. (4) Employment has more positive physical and mental health effects in Individuals with higher rather than lower levels of education. (5) Employment opportunities in the eastern region are more likely to promote better physical health than those in the central and western regions of China, although the effects on mental health are negative. (6) When considering groups at different ages of the lifespan, the 60-65-year-old group, who are just entering retirement probably benefit more from continuing work. We provide some recommendations to encourage middle-aged and older people to work and utilize their experience, which will enhance their physical and mental well-being and help them in realize their own value and social integration.

A Short-Term Traffic Flow Prediction Method for Airport Group Route Waypoints Based on the Spatiotemporal Features of Traffic Flow

To fully leverage the spatiotemporal dynamic correlations in air traffic flow and enhance the accuracy of traffic flow prediction models, thereby providing a more precise basis for perceiving congestion situations in the air route network, a study was conducted on a traffic flow prediction method based on deep learning considering spatiotemporal factors. A waypoint network topology graph was constructed, and a neural network model called graph convolution and self-attention-based long short-term memory neural network (GC-SALSTM) was proposed. This model utilized waypoint flow and network efficiency loss rate as input features, with graph convolution extracting spatial features from the waypoint network. Additionally, a long short-term memory network based on a self-attention mechanism was used to extract temporal features, achieving accurate prediction of waypoint traffic. An example analysis was performed on a typical busy sector of airports in the Central and Southern China region. The effectiveness of adding the network efficiency loss rate as an input feature to improve the accuracy of critical waypoint traffic prediction was validated. The performance of the proposed model was compared with various typical prediction models. The results indicated that, with the addition of the network efficiency loss rate, the root mean square error (RMSE) for eight waypoints decreased by more than 10%. Compared to the historical average (HA), autoregressive integrated moving average (ARIMA), support vector regression (SVR), long short-term memory (LSTM), and graph convolution network and long short-term memory network (GCN-LSTM) models, the RMSE of the proposed model decreased by 11.78%, 5.55%, 0.29%, 2.53%, and 1.09%, respectively. This suggests that the adopted network efficiency loss rate indicator effectively enhances prediction accuracy, and the constructed model exhibits superior predictive performance in short-term waypoint traffic forecasting compared to other prediction models. It contributes to optimizing flight paths and high-altitude air routes, minimizing flight delays and airborne congestion to the greatest extent, thus enhancing the overall efficiency of the entire aviation system.

Climate resilience of urban water systems: A case study of sponge cities in China

Resilience is an important aim of climate adaptation in urban development planning. Since 2015, sponge city (SC) pilot construction in China has highlighted the importance of urban water systems, but has paid insufficient attention to extreme and long-term climate change risks. This paper aims to provide a new method for evaluating the urban water system climate resilience (UWSCR), classify China cities in combination with climate hazards, conduct case studies on SC pilots, and propose ways to improve the UWSCR in SCs. Firstly, Taking heavy rain and drought as hazards, an evaluation index system of UWSCR is established, including engineering resilience (ENR), ecological resilience (ECR) and evolutionary resilience (EVR). A combination model based on the analytic hierarchy process and entropy weight method is used to measure the UWSCR of 27 SC pilot cities and 253 non-pilot cities at or above the prefecture level in China. Secondly, coordinating hazard index and UWSCR index, cities are divided into four types. The results show that the ENR and EVR of SC pilots exhibited an increasing trend from 2010 to 2020 and were greater than those of non-pilots. Among the four types, Resilient Cities and Low Risk Cities with high climate resilience (CR) were mainly distributed in the eastern and central regions of China. High Risk Cities and Vulnerable Cities with low CR were mostly distributed in the central and western regions. Among the cities of high CR, SC pilots accounted for 63.0% of the pilot samples, while non-pilots only accounted for 26.5% of the non-pilot samples. Finally, this paper analyzes the typical cases of SC pilots, and puts forward some suggestions, such as considering the UWSCR systematically and holistically, improving the ECR of UWSCR, making medium-term to long-term adaptation planning and providing differentiated policy support. The originality of this work is to identify four types of cities from the perspective of UWSCR and provide reference for improving the CR of SCs.

Enhancing environmental sustainability in transferred farmlands through rural e-commerce: insights from China.

The issue of farmers neglecting environmental concerns in transferred farmlands poses a serious challenge, contradicting the long-term ecological goals of establishing resource-efficient and environment-friendly agriculture. Amidst the pivotal trend of moderately scaled agricultural operations, rural e-commerce holds promise as a catalyst and driving force for enhancing long-term environmental governance of transferred lands. The effectiveness and mechanisms of this potential, however, remain to be empirically examined. This study gathers panel data on environmental positive and negative externalities from six provinces in China, spanning the period from 2013 to 2022, encompassing 6372 farmers. A quasi-natural experiment of farmers' e-commerce participation is designed using difference-in-differences methodology (DID), propensity score matching (PSM), and moderating models. The primary findings are as follows: E-commerce participation increases farmers' positive environmental inputs on transferred lands, such as water-saving irrigation, adoption of social services, and preservation of traditional varieties. Simultaneously, it decreases negative environmental inputs, such as the consumption of fertilizers, pesticides, and agricultural films. The environmental sustainability effects of e-commerce vary across the eastern, central, and western regions of China. E-commerce has a more pronounced impact on agricultural social services and chemical pollutants in the eastern and central regions, while its influence is more significant on water-saving irrigation and variety preservation in the western region. Land transfer forms and supply order contracts do not directly promote farmers' environmentally friendly cultivation practices. Instead, they catalyze the environmental effects of e-commerce through a significant positive interaction term. These conclusions hold after matching for e-commerce participation propensity, while passing sensitivity tests, parallel trend tests, and placebo tests. Consequently, rural e-commerce, without compromising farmers' income, enhances the proactiveness of farmers in environmental conservation, transforms agricultural management practices, and effectively reduces rural non-point source pollution. Policy recommendations include reducing institutional barriers to rural e-commerce participation at the national level, encouraging the establishment of region-specific agricultural environmental sustainability goals, and leveraging the rural e-commerce industry chain to establish a nationwide environmental credit database and incentive mechanism.

Source reduction and innovation: Can sustainable finance assist in mitigating haze pollution?

In the context of China's pursuit of an ecological civilization, controlling haze pollution (HP) and enhancing environmental quality occupy a pivotal role. Addressing this issue, this study utilizes a dataset spanning from 2006 to 2020, encompassing 278 Chinese cities, to examine the impact and mechanisms of sustainable finance on HP management. This research innovatively constructs a Sustainable Finance Index and employs fixed effects models, mediation effect models, and spatial Durbin models for comprehensive empirical analysis. The findings indicate a significant negative relationship between sustainable finance and HP, with pronounced effects in cities experiencing severe haze, cities in the central and eastern regions of China, and non-provincial boundary cities. Mechanism analysis reveals that sustainable finance curtails urban haze formation through the optimization of energy consumption structure, enhancement of energy efficiency, and advancement of environmental technologies. This is primarily achieved through pollution source reduction and innovation effects. Additionally, the study uncovers a spatial spillover effect of sustainable finance in mitigating HP, peaking within a 500-km radius. This research not only provides new insights into the role of sustainable finance in the construction of ecological civilization but also offers empirical support for policymakers and stakeholders in formulating clean production policies, enhancing both the academic dialogue and practical policymaking in environmental management and sustainable development.

Evaluation of Two Momentum Control Variable Schemes in Radar Data Assimilation and Their Impact on the Analysis and Forecast of a Snowfall Case in Central and Eastern China

To evaluate the impact of different momentum control variable (CV) schemes (CV5, the momentum control variable option with ψχ and CV7, the momentum control variable option with UV) on radar data assimilation (DA) in weather research and forecasting model data-assimilation (WRFDA) systems, a heavy snowfall in central and eastern regions of China, which started on 6 February 2022, was taken as a case in this study. The results of the wind-field increments from the single observation tests indicated that the wind-field increments had a larger range of influence when stream function and velocity potential (ψχ) were used as momentum control variables in CV5. Some spurious increments were also generated in the wind-field analysis, since CV5 tended to maintain the integrated value of the wind field. When U-wind and V-wind were used as control variables in CV7, the wind-field increments had a smaller impact range, and there was less dependence among different locations on the wind increments. For the heavy snow case, the CV7 schemes displayed some improvements in simulating the composite reflectivity compared to the other two experiments, since the composite reflectivity in the CV5 and control experiments were overestimated to some level. It was also found that the RMSEs were lower in the CV7 compared to those in the CV5 in the short-term forecasts during the data-assimilation cycles. Results also indicated that the CV7 had a more significant effect on the 6 h accumulated precipitation forecasts. Meanwhile, the experiment Exp_CV7 achieved the best ETS and FSS scores among the three groups of experiments, while Exp_CV5 appeared to be generally superior to the CTRL. In summary, the precipitation of Exp_CV7 yielded the rainfall intensity and location most close to the observation compared to those from both the CTRL and Exp_CV5 experiments.

The Impact of Cross-Border Mergers and Acquisitions on Corporate Organisational Resilience: Insights from Dynamic Capability Theory

Utilising panel data from Chinese listed companies between 2008 and 2020, this study employs propensity score matching (PSM) in conjunction with a multi-temporal difference-in-differences (DID) model to examine the causal impacts of cross-border mergers and acquisitions (M&As) on the organisational resilience of enterprises. The findings reveal that while cross-border M&As augment company risk-taking and short-term financial volatility, they also bolster long-term growth, thereby enhancing overall organisational resilience. Cross-border M&As are particularly beneficial for bolstering organisational resilience in state-owned enterprises, non-manufacturing firms, and companies located in the eastern and central regions of China. Moreover, adhering to the principles of corporate social responsibility and possessing substantial market power are found to enhance the impact of cross-border M&As on organisational resilience. The results of this research hold important practical implications for companies seeking to improve organisational resilience and achieve sustainable development.

Synergistic effects of pollutant control: Evidence from China's sulfur dioxide emission control policy

This study investigates the impact of China's national sulfur dioxide emission control policies on carbon dioxide emissions. Using the difference-in-difference-in-differences (DDD) estimation method, we analyze the synergistic effects of environmental regulations on pollution control and carbon emission reduction. Empirical findings demonstrate that sulfur dioxide emission regulations have a significant effect on reducing firms' carbon dioxide emissions, primarily through energy conservation measures. Furthermore, results reveal variations in the effectiveness of these regulations across different types of firms and regions. Specifically, state-owned and large-scale firms, along with those situated in the eastern and central regions of China, exhibit greater energy-saving and emission-reducing effects in response to the regulations. Notably, these regulations lead to unexpected energy savings and emission reductions without compromising output, highlighting improvements in energy efficiency as a key driver. These findings underscore the importance of recognizing the potential synergies between pollutant control policies and carbon emission reduction goals. To maximize these positive effects, policymakers should prioritize strategies to enhance energy efficiency and tailor environmental regulations to suit the unique characteristics of firms and regions. Overall, this study contributes valuable insights to the development of effective environmental policies in the context of carbon peaking and neutrality objectives of China.

Children's dietary patterns and dietary networks in five regions in China

To analyze the dietary patterns and dietary networks of children in China, explore regional differences in dietary habits in each region. The subjects of the study were children aged 3-17(n=5824) in North Coast Economic Zone, Northeast, Central China, East Coast Economic Zone and Southwest Economic Zone who participated in the China Health and Nutrition Survey. The dietary pattern was obtained by factor analysis. Using mutual information, a measure to detect both linear and non-linear correlations between food groups constructed the dietary networks. Factor analysis resulted in five dietary patterns. Pattern 1 was related to high intakes of wheat and other cereals, pattern 2 was related to high intakes of fruits, milk, eggs and fast foods, pattern 3 was associated with high intakes of tubers, snacks, cakes, beverages and fast foods. The Northeast, Central China and North Coast Economic Zone regions had higher pattern 1 score. Pattern 2 scored higher for North Coast Economic Zone and East Coast Economic Zone regions. Pattern 3 scores in the Northeast region were higher than North Coast Economic Zone and East Coast Economic Zone regions. North Coast Economic Zone, Central China and Southwest Economic Zone regions had focused networks. The network of Northeast and East Coast Economic Zone regions were multiple. All regions were characterized by vegetables, or cereals as the hub. The dietary patterns and networks of children in the five regions of China exhibit regional differences.

Association of Depressive and Anxiety Symptoms With Risk of Cardiovascular Disease in Middle-Aged and Older Chinese Women.

The objective of this study was to estimate the association of depressive and anxiety symptoms with the risk of cardiovascular disease (CVD) in middle-aged and older Chinese women and to further evaluate whether the association was influenced by sociodemographic factors. This cross-sectional study included 9544 women aged 40 to 70 years from the eastern, central, and western regions of China in 2018. Logistic regression models were utilized to examine odds ratios (ORs) and their 95% confidence intervals (CIs) for depressive and anxiety symptoms with CVD risk. Depressive (OR = 1.89) and anxiety symptoms (OR = 1.55) were independently associated with an increased risk of CVD after adjusting for potential confounders. Stratified analyses found that depressive symptoms were only significantly associated with higher risk of CVD in women aged over 50 years and with lower levels of education and household income, whereas anxiety symptoms were only significantly associated with an elevated risk of CVD in women aged 60 to 70 years, and living in rural areas, and with lower levels of education and household income. Our findings emphasize the improvement of recognizing and managing depressive and anxiety symptoms to reduce the risk of CVD in middle-aged and older women, particularly in older women of low socioeconomic status.

Diurnal variation in short‐ and long‐duration precipitation within the Dabie Mountain region in Central China

AbstractDiurnal variation in regional precipitation in Central and East China has been broadly identified in previous study. This study focused on clarifying not only the differences in the diurnal variation concerning the local precipitation occurred in the Dabie Mountain (DBM) region and the regional precipitation occurred through the middle‐lower reaches of the Yangtze River Basin, but also the association mechanism between diurnal variation in local precipitation with differing duration and diurnal modulation of ambient circulations driven by large‐scale background synoptic force or local‐scale orographic force of the DBM. It was found that cases of short duration precipitation (SDP, duration <6 h) and cases of long duration precipitation (LDP, duration ≥6 h) exhibit vastly different patterns of diurnal variations. Further investigation revealed that the primary pattern of the ambient circulation responsible for SDP and LDP is the recycling transformation between a closed cyclonic circulation to a cyclonic wind shear, and the recycling movement of a closed cyclonic circulation in the lower troposphere respectively. Although the diurnal variation in LDP exhibited greater orographic regional differences between the west slope (WS) region and the east slope (ES) region in comparison with that of SDP, topographical sensitivity experiments of the DBM and detailed analysis of background synoptic systems associated with LDP indicated that this regional orographic difference shows closer association with eastward propagation of background synoptic systems than orographic effects of the DBM. Respective strengthening of upward vertical motion at different levels of the troposphere during diurnal variation in SDP and LDP cases provide substantial evidences to reconfirm the close association with orographic force in lower the troposphere for SDP cases and background synoptic force in middle troposphere for LDP cases. Further quantitative diagnosis also confirmed that the orographic effects of the DBM is conducive to cause marked differences in the diurnal variation in SDP cases between the WS region and the ES region via adjustment of the upslope wind over the former and the circumventing wind over the latter.

Entrepreneurial spirit: A catalyst on the road to green and sustainable development——A theoretical analysis based on dynamic games and empirical tests from Chinese data

Environmental protection and sustainable development are now profoundly ingrained in the public consciousness in the modern era of the global green revolution. First, this paper uses an evolutionary game model to theoretically analyse the impact of environmental regulation and green finance on enterprises by dissecting the game behaviour between local governments, banks and enterprises. Then, we incorporate entrepreneurial spirit into the model to determine whether entrepreneurial spirit accelerates the achievement of green sustainability objectives. Environmental regulation and green finance are found to contribute substantially to the innovation of green technologies by local enterprises, while entrepreneurial spirit accelerates this process. Finally, we empirically test the findings based on a prefecture-level panel dataset from 2007 to 2020. We find that green finance has a positive impact in Central and Western cities of China, while Eastern cities are in greater need for government environmental regulation controls. For entrepreneurial spirit, the incentive effect of entrepreneurial spirit on the level of green technology innovation is more significant in Central and Western regions of China. This paper enriches the field of research on entrepreneurial spirit and regional green sustainable development by providing empirical evidence for the evaluation of environmental regulatory and green financing policy impacts.

Incidence and case fatality rates of cardiovascular diseases in urban and rural community-dwelling populations in eastern, central and western regions of China

Objective: To evaluate the incidence and case fatality rate of cardiovascular disease (CVD) among populations in urban and rural communities in eastern, central and western regions of China. Methods: The present study was based on the data of the Prospective Urban and Rural Epidemiology (PURE)-China cohort, which enrolled participants who had at least one follow-up visit and complete information on age and sex. Information on baseline demographics, cardiovascular risk factors, and prevention and treatment for CVD were collected. CVD and mortality events were documented using the standardized case report form of the PURE Global Study to assess the incidence and case fatality rate of CVD among populations in urban and rural communities in eastern, central and western China. Results: This study included a total of 47 262 community-dwelling participants (age: (51.1±9.6) years; female, n=27 529, 58.2%) from 115 urban and rural communities in 12 provinces across the eastern, central, and western regions of China. Over a follow-up period of 11.9 (9.5, 12.6) years, 2 686 deaths and 5 873 cardiovascular events were documented. The incidence of CVD was 11.90 (95%CI: 11.60-12.21)/1 000 person-years. A significant difference in CVD incidence was observed across regions (Ptrend<0.001), which was highest in the western provinces (13.99 (95%CI: 13.33-14.65)/1 000 person-years), intermediate in the eastern provinces (11.92 (95%CI: 11.52-12.33)/1 000 person-years), and lowest in the central provinces (8.87 (95%CI: 8.25-9.50)/1 000 person-years). The 1-year case fatality rate of CVD demonstrated an increasing trend from eastern to western regions (eastern: 10.20% (95%CI: 6.95-14.73); central: 13.50% (95%CI: 9.90-18.14); western: 18.62% (95%CI: 14.95-22.94); Ptrend<0.001). Moreover, the incidence of major CVD was consistently higher in rural areas compared with urban areas across eastern (P<0.001), central (P=0.01) and western (P<0.001)_regions, respectively. The 1-year case fatality rate in rural areas was also significantly higher compared with that in urban areas in both eastern (P<0.001) and western regions (P=0.02). Conclusions: The incidence and case fatality rate of CVD were high among middle-aged population in China, especially those in western regions with low socioeconomic levels and in rural areas.

Construction and application of the "Internet + public health service" supply evaluation index system.

To construct an index system for evaluating the supply of Internet+ public health services, and to provide a practical tool for assessing the supply of Internet+ public health services in an objective and scientific manner. The research team drafted the index system framework by combing the literature. The Delphi method was used to determine the content and weight of the index through two rounds of expert consultations. At the same time, the Cronbach coefficient and factor analysis were adopted to test the reliability and validity. What's more, the analytic hierarchy process and the TOPSIS method were applied to analyze the empirical data of 15 counties and cities in the eastern, central, and western regions of China. The constructed indicator system includes 3 first-level indicators, 6 second-level indicators and 29 third-level indicators. Through reliability and validity tests, the stability and practicability of the index system are demonstrated in empirical research. The evaluation index system constructed in this article can be applied to the performance evaluation of Internet + public health service.

Does digital economy development affect urban environment quality: Evidence from 285 cities in China.

The impact of the digital economy (DE) on urban environmental quality (EQ) is a critical aspect of China's economic development. This study investigates the impact of DI on urban EQ using the data from prefecture-level cities spanning the period from 2011 to 2021 and updates some disparate conclusions of related studies. It is discovered that a non-linear correlation exists between DE and urban EQ. Currently, DE can effectively improve local city EQ. This conclusion remains valid even after robustness tests and endogeneity treatment. The impact of DE on improving EQ can be classified as the impact of technological innovation, industrial upgrading, resource allocation, infrastructure construction, environmental governance, and changes in public lifestyle. Heterogeneity analysis reveals that the influence of DE is particularly pronounced in cities located in central and eastern regions of China, those with higher levels of administrative management, resource-based urban areas, and those with more stringent environmental regulations.

Mental health in China: exploring the impacts of built environment, work environment, and subjective perception.

The shifting living and working conditions have profound impacts on the residents' mental health. However, current research in this field has not remarkable investigated. This study used the China Labor-force Dynamic Survey (CLDS) dataset from 2018 and relied on a regression model to examine the effects of the built environment, work environment, and subjective perception on the mental health of Chinese citizens. It also considers the circumstances of both migrants and local residents. This study revealed significant correlations between mental health and greening space rate, road network density, commuting time, work feelings, community trust, economic satisfaction, and other factors. Additionally, the mental health of local residents was shown to be significantly affected by community security, while it shows no significance in migrants. Furthermore, a significant spatial autocorrelation was found in terms of mental health within the central and eastern regions of China. The findings of this study offer valuable insights that can be used to facilitate measures aimed at improving the mental health of residents and promoting the development of healthy cities.

"Iron Ion Relative Weathering Index": A New Index for Identifying the Weathering Degree in Red Sandstone.

The red bed region in west central and southern China is affected by hot and humid climate, where sandstone is intensely weathered. The weathered hazardous rocks seriously threaten the road and slope, making it challenging to protect the Danxia red bed. After considering the red sandstone's material composition and the local area's main weathering effects. We noticed that iron ions in red sandstone are susceptible to weathering, which leads to changes in the valence and content of iron ions. This study attempts to establish a new chemical weathering index called the "iron ion relative weathering index" (IRWI) to classify the weathering degree of red sandstone. This paper mainly explores the changes of physical characteristics (mineral composition, physical indicator, microstructure, and pore structure) from the surface to the interior of red sandstone in the actual environment and their correlation with IRWI. The study on the correlation between the physical indicators such as longitudinal wave velocity, resistivity, density, water absorption, and IRWI reveals that they have the same trends and are closely related to the weathering degree. The shallow weathering zone of Chishui red sandstone is divided into strong, medium, and slight weathering zones. Microscopically, the cementation and pore distribution of the red sandstone are consistent with the characteristics of the weathering zone. Therefore, IRWI not only is a reliable chemical quantitative method in indicating the weathering of red sandstone but also takes into account the controlling role of iron in the color development of red beds, which provides a new research idea for the quantitative identification of weathering degree and color mechanism of red sandstone.

Intern-Nursing Students' Knowledge of Vascular Catheter-Associated Infections and Its Associated Factors: A Cross-Sectional Survey in China.

Medical personnel contact with the patient closely, and their knowledge of vascular catheter-associated infections (VCAIs) is closely related to the prevention of VCAIs. Researchers mainly pay attention to the VCAIs knowledge of doctors and nurses but rarely pay attention to the nursing students in the hospital internship stage. To investigate the current situation of knowledge of intern-nursing students in VCAIs, and analyze its influencing factors. 843 intern-nursing students were selected from 10 hospitals in five regions of eastern, western, southern, northern, and central China from June 26 to July 31, 2023, using a two-stage random sampling method. A self-designed questionnaire with good reliability and validity was used to investigate their knowledge of VCAIs, and t-test, multiple linear regression analysis, and Welch t-test were used to analyze the collected data by using SPSS Statistics 26.0 (IBM Corp., Armonk, NY). Intern nursing students' mean score of VCAIs knowledge was 48.66 (SD=15.77), with a score below 60 (unqualified) accounting for 75.4%, a score of 60-79 (qualified) accounting for 19.7%, a score of 80-89 (good) accounting for 3.6%, and a score of above 90 accounting for 1.3%. Students who attended VCAIs training three or more times had higher scores than those who did not attend training (B: 4.706, p=0.001), knowledge scores of students with a bachelor's degree or above were higher than those with junior college degree or below (B: 8.479, p<0.001), students who interned in tertiary hospitals had higher scores than those practicing in secondary hospitals (B:12.381, p<0.001) and scores of students in hospital training were significantly higher than study independently (B:4.116, p=0.007). Intern-nursing students have a relatively low level of knowledge about VCAIs. It is recommended to strengthen clinical systematic and standardized training, improve the knowledge mastery level of intern-nursing students, and enhance their ability to handle VCAIs.