Transmission mechanism of antibiotic resistance genes and their differences between water and sediment in the Weihe River Basin.

Antibiotic resistance genes (ARGs) are emerging microbial pollutants that are regulated by many factors and pose potential threats to aquatic environments. In this study, we used network analysis, correlation analysis, and constructed models based on metagenomic sequencing results to explore the spatial patterns, impact mechanisms, transmission risks and differences in ARGs in the water and sediment of the Weihe River Basin. The findings revealed notable disparities in ARGs, mobile genetic elements (MGEs), and bacterial communities. In the sediment, the abundance of ARGs was considerably greater than that in water. Moreover, the percentage of ARGs shared by the two components reached a value of 85.8%. Through network analysis, it was determined that the presence of 16 MGEs and 20 bacterial phyla was strongly associated with ARGs (R2 > 0.7, P < 0.05). The Mantel test showed that abiotic factors including DO, pH, nutrients, and heavy metals played important roles in the distribution of ARGs (P < 0.05). A structural equation model revealed that the key factors influencing the distribution of ARGs in water were bacterial diversity and environmental parameters (standardized effects of -0.730 and -0.667), and those in sediment were bacterial diversity and MGEs (standardized effects of -0.751 and 0.851). Neutral modeling indicated that deterministic processes played an important role in the assembly of ARGs in the water of the Weihe River Basin, and stochastic processes were dominant in the sediment. There was a highly significant positive linear correlation between ARGs and pathogens, and there was more complex co-occurrence in the water than in the sediment (R2 > 0.9, P < 0.05), with stronger migration and transmission occurring. Exploring ARGs in large-scale watersheds is immensely important for elucidating their traits and transmission mechanisms and consequently paving the way for the formulation of efficient strategies to mitigate resistance threats.

Photolysis of dinotefuran and nitenpyram in water and ice phase: Influence mechanism of temperature over photolysis.

Neonicotinoids are widely used pesticides around the world, but the photolysis of neonicotinoids in cold agricultural region are still in blank. This paper aimed to study the influence of cold temperature over photolysis of neonicotinoids. To this end, the photolysis rates and photoproducts of dinotefuran and nitenpyram in water, ice and freeze-thawing condition were determined. Coupled with quantum chemistry calculation, the influence mechanisms of temperature and medium were investigated. The results showed the photolysis rates of neonicotinoids in water condition slightly declined with the lowered temperature due to the photolysis reactions were endothermic reactions. However, the photolysis rates increased by 89.8 %, 59.2 %, 49.4 % and 9.5 % for dinotefuran and nitenpyram in ice and thawing condition, respectively. This phenomenon was posed by the concentration-enhancing effect and change of photo-chemical properties of neonicotinoids in ice condition, which included lowered bond cleavage energy, lowered first excited singlet state energy and expanded light absorption range. The photolysis pathways of the two neonicotinoids did not change in different medium, but the concentration of carboxyl products was relatively higher than that of water condition due to the more amounts of reactive oxygen species in ice medium, which might increase the secondary pollution risk after ice-off in spring due to the higher ecotoxicity to nontarget organism of these photoproducts. The influence of cold temperature and medium change should be considered for the environmental fate and risk assessment of neonicotinoids in cold agricultural region.

Evaluating annual soil carbon emissions under biochar-added farmland subjecting from freeze-thaw cycle.

Straw biochar is a commonly recognized agricultural amendment that can improve soil quality and reduce carbon emissions while sequestering soil carbon. However, the mechanisms underlying biochar's effects on annual soil carbon emissions in seasonally frozen soil areas and intrinsic drivers have not been clarified. Here, a 2-y field experiment was conducted to investigate the effects of different biochar dosages (0, 15, and 30, t ha-1; B0 (CK), B15, and B30, respectively) on carbon emissions (CO2 and CH4) microbial colony count, and soil-environment factors. The study period was the full annual cycle, including the freeze-thaw period (FTP) and the crop growth period (CP). Structural equation modeling (SEM) was developed to reveal the key drivers and potential mechanisms of biochar on carbon emissions. Biochar application reduced soil carbon emissions, with the reduction rate positively related to the biochar application rate (B30 best). During FTP, the reduction rate was 11.5% for CO2 and 48.2% for CH4. During CP, the reduction rate was 17.9% for CO2 and 34.5% for CH4. Overall, compared with CK, B30 treatment had a significant effect on reducing total soil carbon emissions (P < 0.05), with an average decrease of 16.7% during the two-year test period. The study also showed that for soils with continuous annual cycles (FTP and CP), carbon emissions were best observed from 10:00-13:00. After two years of freeze-thaw cycling, biochar continued to improve soil physical and chemical properties, thereby increasing soil microbial colony count. Compared with B0, the B30 treatment significantly increased the total colony count by 74.3% and 263.8% during FTP and CP (P < 0.05). Structural equation modeling (SEM) indicated that, with or without biochar application, the soil physicochemical properties directly or indirectly affected soil CO2 and CH4 emission fluxes through microbial colony count. The total effects of biochar application on CO2 emission fluxes were 0.50 (P < 0.05) and 0.64 (P < 0.01), respectively, but there was no significant effect on CH4 emission fluxes (P > 0.05). Among them, soil water content (SWC), soil temperature (ST) and soil organic carbon (SOC) were the main environmental determinants of CO2 emission fluxes during the FTP and CP. The total effects were 0.57, 0.65, and 0.53, respectively. For CH4, SWC, soil salinity (SS) and actinomycete colony count were the main environmental factors affecting its emission. The total effects were 0.50, 0.45, 0.44, respectively. For freeze-thaw alternating soils, the application of biochar is a feasible option for addressing climate change through soil carbon sequestration and greenhouse gas emissions mitigation. Soil water-heat-salt-fertilization and microbial communities are important for soil carbon emissions as the reaction matrix and main participants of soil carbon and nitrogen biochemical transformation.

Influence of E-consultation on the Intention of First-Visit Patients to Select Medical Services: Results of a Scenario Survey.

BACKGROUND: E-consultation is expected to improve the information level of patients, affect patients' subsequent judgments of medical services, and guide patients to make a reasonable medical selection in the future. Thus, it is important to understand the influence mechanism of e-consultation on patients' medical selection. OBJECTIVE: This study aims to explore the changes in first-visit patients' understanding of disease and medical resources after e-consultation as well as the choice of follow-up medical services. METHODS: Patients' medical selection before and after e-consultation was compared using a scenario survey. Based on the service characteristics of the e-consultation platform, representative simulation scenarios were determined, and parallel control groups were set up considering the order effect in comparison. Finally, a total of 4 scenario simulation questionnaires were designed. A total of 4164 valid questionnaires were collected through the online questionnaire collection platform. Patients' perception of disease severity, evaluation of treatment capacity of medical institutions, selection of hospitals and doctors, and other outcome indicators were tested to analyze the differences in patients' evaluation and choice of medical services before and after e-consultation. Additionally, the results' stability was tested by regression analysis. RESULTS: In scenario 1 (mild case), before e-consultation, 14.1% (104/740) of participants considered their conditions as not serious. After e-consultation, 69.5% (539/775) of them considered their diseases as not serious. Furthermore, participants' evaluation of the disease treatment capacity of medical institutions at all levels had improved after using e-consultation. In scenario 3 (severe case), before e-consultation, 54.1% (494/913) of the participants believed their diseases were very serious. After e-consultation, 16.6% (157/945) considered their diseases were very serious. The evaluation of disease treatment capacity of medical institutions in nontertiary hospitals decreased, whereas that of tertiary hospitals improved. In both mild and severe cases, before e-consultation, all of the participants were inclined to directly visit the hospital. After e-consultation, more than 71.4% (553/775) of the patients with mild diseases chose self-treatment, whereas those with severe diseases still opted for a face-to-face consultation. After e-consultation, patients who were set on being treated in a hospital, regardless of the disease severity, preferred to select the tertiary hospitals. Of the patients with mild diseases who chose to go to a hospital, 25.7% (57/222) wanted to consult online doctors face-to-face. By contrast, 56.4% (506/897) of the severe cases wanted to consult online doctors face-to-face. CONCLUSIONS: E-consultation can help patients accurately enhance their awareness of the disease and guide them to make a more reasonable medical selection. However, it is likely that e-consultation makes online medical services centralized. Additionally, the guiding effect of e-consultation is limited, and e-consultation needs to be combined with other supporting systems conducive to medical selection to play an improved role.

The Contribution of the Internet to Promoting Mental Health for Older Adults: Cross-Sectional Survey in China.

BACKGROUND: Health is an important topic for everyone and essential to high-quality economic and social development. Recently, some researchers have suggested that older adults' internet use may have a health effect. OBJECTIVE: This study specifically aims to clarify the relationship between internet use and the mental health of older adults, for which other surveys present contradictory results. METHODS: Data were obtained from the China Longitudinal Aging Social Survey conducted in 2018. A total of 6648 participants were included. Mental health was assessed by the 12-item Center for Epidemiological Studies Depression Scale. Ordinary least squares regression was adopted to explore the relationship between internet use (independent variable) and the mental health of older adults. Robustness analysis, sensitivity analysis, and heterogeneity analysis were conducted in detail to verify the empirical result. A mediating effect analysis was further conducted to discover the effect mechanism between the dependent and independent variables. RESULTS: It was found that internet use and smartphone use can significantly improve the mental health of older adults (ordinary least squares, ß=.075; P<.001). After endogenous and robustness tests were conducted, the aforementioned conclusion remained robust. In particular, participation in voluntary activities played a mediating role in the relationship between internet use and the mental health of older adults. In addition, younger subjective age enhanced the positive effect of internet use on the mental health of older adults. CONCLUSIONS: Internet users showed higher levels of mental health among Chinese older adults. To improve the mental health of older adults, the government should not only cultivate the ability to use the internet but also encourage greater participation in voluntary activities among older adults.

The effective subsidy policies for new energy vehicles considering both supply and demand sides and their influence mechanisms: An analytical perspective from the network-based evolutionary game.

The development of new energy vehicles (NEVs) cannot be separated from the support of subsidy policies. However, the effectiveness of different subsidy policies remains to be verified. To investigate a more effective way of NEV subsidy and maximize the effect of subsidy policies, this study proposes two subsidy strategies, namely, consistent subsidy and adaptive subsidy, and constructs a network-based evolutionary game model for NEV diffusion. The effects of different subsidy policies are then comprehensively evaluated from the supply and demand sides, and their internal influence mechanisms are further investigated. Results show that: 1) from the supply side, subsidy for both policy achieves the highest NEV diffusion, but subsidy for enterprises is more efficient; 2) from the demand side, NEV diffusion increases NEV sales in the same proportion. Surprisingly, the increase in NEV diffusion rate benefits traditional vehicle manufacturers by expanding their average market demand; 3) from the cost-benefit analysis, the adaptive subsidy is more efficient than consistent subsidy; 4) The higher the initial benefits of NEV enterprises, the higher the level of NEV diffusion. The government should implement the adaptive subsidy and focus on providing subsidies to NEV enterprises to increase the NEV diffusion rate and achieve efficient resource allocation.

Characteristics of greenhouse gas emissions from farmland soils based on a structural equation model: Regulation mechanism of biochar.

Greenhouse gas (GHG) emissions from soil carbon and nitrogen cycles during freeze-thaw cycles (FTCs) provide positive feedback to climate warming. Biochar is a new type of soil conditioner that shows potential in soil GHG emissions reduction. To explore the mechanisms of the effects of biochar on soil GHG emissions in seasonally frozen soil areas, this study focused on farmland soil in the Songnen Plain. Variations in soil environmental factors, available carbon and nitrogen and microbial biomass were analyzed using an indoor simulation of soil FTCs. A structural equation model (SEM) was established to reveal the key driving factors and potential mechanism of biochar on soil GHG emissions under FTCs. The results showed that biochar increased carbon dioxide (CO2) emissions by 3.40% and methane (CH4) absorption by 2.52% and decreased nitrous oxide (N2O) emissions by 35.90%. SEM showed that soil temperature (ST) was the main environmental factor determining CO2 emissions and that soil moisture (SM) was the main environmental factor determining CH4 and N2O emissions. Soil available carbon and nitrogen and microbial biomass are important for soil GHG emissions as the reaction substrates and main participants in the biochemical transformation of soil carbon and nitrogen, respectively. This study showed that the application of biochar in farmland is a feasible choice to address climate change in the long term via soil carbon sequestration and GHG emissions reduction. The research results provide a theoretical basis and scientific guidance for soil GHG emissions reduction during FTCs in middle to high latitudes.

Evaluating the influence of financial investment in compulsory education on the health of Chinese adolescents: a novel approach.

BACKGROUND: With China's aging and declining fertility rate, the importance of population quality is increasing. As the main force of the labor market in the future, the Chinese government tries to promote the development of adolescents by increasing the financial investment in compulsory education, so as to improve the future population quality of China and enhance the national competitiveness. Therefore, the aim of this study was to investigate the relationship between financial investment in compulsory education and the health of Chinese adolescents. METHODS: This study specifically uses data obtained from China Education Panel Survey (CEPS). The data were nationally representative, which covered families, schools, and communities. For the CEPS data obtained, the 2013-2014 school year was the baseline, and two cohorts of 7th and 9th graders were the starting point of the survey. In the 2014-2015 school year, 8th-grade students who participated in the baseline survey (7th-grade students in the 2013-2014 school year) were followed up. Since the second period only began to investigate the data on financial investment in compulsory education, this article uses the data from the 2014-2015 academic year for research. OLS and Ordered Probit models were used to investigate the impact of financial investment in compulsory education on adolescent health. RESULTS: With the doubling of financial investment in compulsory education, self-rated health increased by 0.021, frequency of illness decreased by 0.03, the number of sick leave days decreased by 0.207, and depression decreased by 0.191. The heterogeneity analysis shows that compared to only-child, high-income and nonagricultural groups, the financial investment in compulsory education has a greater impact on the health of adolescents with the characteristics of agriculture hukou, non-only-child and low-income families. Further analysis of the impact mechanism shows that financial investment in compulsory education exerts a significant influence on the health of adolescents by easing family budget constraints, improving school sports facilities, and increasing the expected return of health investment and social capital. CONCLUSIONS: Financial investment in compulsory education can enhance the health of adolescents, and vulnerable groups benefit more, which is conducive to promoting health equity.

Exploring the influence mechanism of dissolved organic matter on the bioavailability and thyroid hormone disrupting effect of zinc: A case study of effluents from galvanizing plants.

The effect of dissolved organic matter (DOM) on metal bioavailability and toxicity is a complex process. Effluents from galvanizing plants containing large amounts of DOM and Zn were selected to investigate the potential influence and mechanism of DOM on Zn bioavailability and its role in inducing thyroid hormone disrupting effects. Thyroid hormone disrupting effects were evaluated using a recombinant thyroid hormone receptor ß gene yeast assay. The results suggest that Zn could be the main metal contributor to the toxic effects. Then, Zn-binding characteristics with different fluorescent components of DOM were analyzed using three-dimensional excitation emission matrix fluorescence spectroscopy (3DEEM) and revealed that Zn was more susceptible to interactions with fulvic-like materials. Furthermore, DOM altered the cellular biouptake and compartmentalization processes of Zn by downregulating Zn transmembrane transport-related genes (ZRT1, ZRT2 and ZAP1) and upregulating detoxification-related genes (COT1 and ZRC1), thus altering thyroid toxicity. These results provide comprehensive insights into the influence and mechanism of DOM on bioavailability and thyroid toxicity of Zn and suggest that the influence is associated with complex physical, chemical and biological processes, indicating that more refined medium constraints along with subtle biological reactions should be considered when predicting the bioavailability and toxicity of Zn in environmental water samples.

Effect of Uneven Electrostatic Forces on the Dynamic Characteristics of Capacitive Hemispherical Resonator Gyroscopes.

The hemispherical resonator gyroscope (HRG) is a typical capacitive Coriolis vibratory gyroscope whose performance is inevitably influenced by the uneven electrostatic forces caused by the uneven excitation capacitance gap between the resonator and outer base. First, the mechanism of uneven electrostatic forces due to the significantly uneven capacitance gap in that the non-uniformity of the electrostatic forces can cause irregular deformation of the resonator and further affect the performance and precision of the HRG, was analyzed. According to the analyzed influence mechanism, the dynamic output error model of the HRG was established. In this work, the effect of the first four harmonics of the uneven capacitance gap on the HRG was investigated. It turns out that the zero bias and output error, caused by the first harmonic that dominates mainly the amplitude of the uneven capacitance gap, increase approximately linearly with the increase of the amplitude, and periodically vary with the increase of the phase. The effect of the other three harmonics follows the same law, but their amplitudes are one order of magnitude smaller than that of the first one, thus their effects on the HRG can be neglected. The effect of uneven electrostatic forces caused by the first harmonic on the scale factor is that its nonlinearity increases approximately linearly with the increase of the harmonic amplitude, which was analyzed in depth. Considering comprehensively the zero bias, the modification rate of output error, and scale factor nonlinearity, the tolerance towards the uneven excitation capacitance gap was obtained.

Influence of ammonium nitrate on the crystallisation of ammonium sulfate.

This study aims to explore the influence mechanism of ammonium nitrate produced by ozone denitrification on the crystallisation of ammonium sulfate, a by-product of ammonia desulfurisation. The laser method was used to study the influence of ammonium nitrate on the solubility and metastable zone width of ammonium sulfate. An experiment on the influence of ammonium nitrate on the particle size of ammonium sulfate was designed, and the influence mechanism was explored through scanning electron microscopy and X-ray diffraction. The findings showed that the addition of ammonium nitrate increased the size and aspect ratio of ammonium sulfate crystals. The addition of ammonium nitrate inhibited the dissolution of ammonium sulfate and widened its metastable zone. The addition of ammonium nitrate covered the active sites of crystal nucleus growth, which inhibited the formation of crystal nuclei to a certain extent, and crystal growth dominated the crystallisation process. Moreover, the addition of ammonium nitrate induced the preferred orientation of the specific crystal plane of ammonium sulfate, and the addition of a small concentration of ammonium nitrate decreased the crystallinity of ammonium sulfate. The research results can provide a reference for crystallisation optimisation and quality improvement of ammonium sulfate in the ammonia desulfurisation process.

Issues and Perspectives for the Study of Disruptive Clinician Behavior.

This article discusses issues and perspectives related to the study of disruptive clinician behavior (DCB) to improve patient safety and healthcare professionals' work environments. Multiple terminologies and ambiguous definitions have resulted in conceptual confusion in studies on DCB. In addition, subjective classifications have led the attributes of DCB to overlap and fluctuate. Therefore, we share Rosenberg's definition of DCB as "any inappropriate behavior, confrontation, or conflict, ranging from verbal abuse to physical and sexual harassment." It is recommended that DCB be understood as a hierarchical structure identified through statistical analysis of field survey data. Furthermore, a recurring list of items is duplicated across existing studies on DCB triggers, contributing factors, and influences. These items can be organized into separate path models based on their mutual relationships. Given these assumed models, we believe that further studies on DCB can shift toward elucidating the mechanisms of occurrence and impact. Finally, based on the path models, we recommend improving healthcare professionals' psychological and social states through a policy shift from "zero-tolerance" to "to err is human" as a priority issue for DCB prevention and countermeasures.

Green space exposure and Chinese residents' physical activity participation: empirical evidence from a health geography perspective.

Background: With continuous efforts made to promote the strategic goals of carbon neutrality and carbon peak, it is crucial to meet the growing and diversified needs of the public for fitness by practicing the concept of green development and promote the combination of national fitness and ecological civilization. Methods: To achieve this purpose, an OLS regression model was applied to estimate the role of green space exposure in Chinese residents' participation in physical activity and its underlying mechanisms, using the microdata from the China General Social Survey (CGSS) data and the Provincial Vegetation Cover Index (NDVI) matched macrostatistical data. Results: The empirical results show that green space exposure significantly increases the probability of residents' physical activity participation, and creating a green environment is conducive to creating a favorable physical activity environment for residents. Also, the core conclusions still hold after the year-by-year regression test is passed and the endogeneity problem is addressed. As revealed by mechanistic studies, green space exposure has indirect effects on the physical activity participation of residents through the independent mediating roles of reducing carbon emissions and promoting social interaction. According to heterogeneity results, males, those in marriage, and urban dweller groups are more inclined to perform physical activity in green spaces. Conclusion: The results show that the exposure of green space can help increase the probability of residents' participation in physical exercise, and can that it achieved through two channels: reducing carbon emissions and enhancing social interaction. It is necessary to further strengthen the protection of the ecological lifestyle, give full play to the advantages of greenness and low-carbon, and create favorable conditions for the green development of a new model of national fitness.

The influence mechanism of resource sharing on tourism industry innovation.

The development of the concept of "sharing" in the era of the digital economy has promoted significant changes in the innovation mechanism of the tourism industry. This article takes 31 provinces (municipalities and districts) in China as the research object, and collect four types of tourism statistics. Inspired by resource-based theory and dynamic capability theory, the article builds a research model of resource sharing for tourism industry innovation, proposes relevant hypotheses, discusses the influence mechanism of tourism industry innovation, and uses a fixed effects model and intermediary mechanism model for empirical test. The results show that the constructed model has good explanatory power and adaptability. Resource sharing can significantly drive tourism industry innovation, and the conclusion is robust. Tourism industry marketization, innovation ability, and competitiveness play an intermediary role in resource sharing to promote tourism industry innovation. The influence of resource sharing on tourism industry innovation has regional heterogeneity. The article aims to reveal the influence mechanism of resource sharing on tourism industry innovation under the digital economy, and the research conclusions can provide references for various provinces (municipalities and districts) to improve regional industrial innovation ability.

Studying tourism development and its impact on carbon emissions.

Analyzing the influence of tourism on carbon emission has significant implications for promoting the sustainable development of tourism. Based on the panel data of 31 tourist cities in China from 2005 to 2022, this study utilizes a structural equation model to explore the carbon reduction effect of tourism development and its influencing mechanism. The results show that: (1) The overall carbon emission efficiency of tourism cities first decreased and then increased, rised to a peak of 0.923 in 2022. (2) Tourism development has a significant positive impact on carbon emission efficiency, and there are three influence paths: tourism → environmental regulation → carbon emission efficiency, tourism → environmental regulation → industrial structure → carbon emission efficiency, and tourism → industrial structure → carbon emission efficiency. (3) The influence of tourism development on carbon emission efficiency mainly depends on the direct effect, and the development of tourism also indirectly affect the industrial structure. Environmental regulation also mainly depends on the direct effect on carbon emission efficiency. (4) Foreign direct investment lead to the reduction of carbon emission efficiency in both direct and indirect aspects.

Neglected negative effect of carbon quantum dots (CQDs) entering the ocean on marine organisms living in different water layers.

Carbon quantum dots (CQDs) are well dispersed in water, but their potential risks in the marine environment have not been described. This study characterized CQDs and investigated their biological effects (including growth, photosynthesis and behavioural changes) in three marine organisms living in different water layers (the surface phytoplankton Phaeodactylum tricornutum and zooplankton Artemia salina and the benthic coral Zoanthus sp. at the bottom). The results showed that over 78 % of CQDs were suspended in seawater after 96 h. The biomass and photosynthesis of P. tricornutum were significantly affected, with a maximum reduction of 89.49 % in algal cells. CQDs accumulated in the intestinal tract of A. salina, reducing grazing and filtration rates by up to 71.88 % and 89.46 %, respectively. In contrast, CQD exposure had irreversible effects on the tentacle expansion behaviour of Zoanthus sp. This study helps clarify the environmental effects and ecological risks associated with the release of CQDs into the ocean.

Influence mechanism of green finance on regional emission reduction.

The implementation of green finance is crucial in achieving a reduction in regional emissions. As such, understanding how green finance affects regional emission reduction is essential. Using provincial panel data from 2008 to 2019, we employed the fixed effects model to examine the impact of green finance on regional emission reduction. The empirical results reveal the following: (1) Green finance has a negative effect on sulfur dioxide intensity, and the development of green finance can significantly reduce the emission of regional pollutants. (2) Among the different instruments of green finance, green credit and green investment exhibit more substantial emission reduction effects than green securities and green insurance. (3) The mechanism by which green finance affects regional emission reduction is mainly through the advanced industrial structure and green technology innovation. (4) The development of green finance shows geographical discrepancies: The eastern region of China is more effective in reducing emissions than the central and western regions. To fully maximize the role of green finance in emission reduction, this paper offers pertinent suggestions for strengthening the green financial system, improving the advanced industrial process, increasing investment in green energy technology, and formulating specific development tactics that consider the prominent characteristics of distinct regions.

Impact of National Centralized Drug Procurement policy on chemical pharmaceutical enterprises' R&D investment: a difference-in-differences analysis in China.

Objective: This study aimed to evaluate the impact of the National Centralized Drug Procurement (NCDP) policy on chemical pharmaceutical enterprises' R&D investment and provide references for improving NCDP policy design and encouraging innovation in the pharmaceutical industry. Methods: Using the panel data of 102 Shanghai and Shenzhen A-share listed enterprises from 2016 to 2022 under the chemical pharmaceutical classification of Shenwan in Wind database as the research sample, this study developed difference-in-differences (DID) models on bid-winning and bid-non-winning enterprises, respectively, to evaluate the impact of NCDP policy on their R&D investment. In addition, this study tested the heterogeneity of bid-winning enterprises based on the bid success rate, the decline of drug price, and enterprise size. Results: The NCDP policy could encourage chemical pharmaceutical companies to increase R&D investment, but the low bid success rate and excessive drug price reduction would reduce their R&D enthusiasm, especially for small- and medium-sized enterprises. Discussion: It is suggested that the NCDP policy should be further improved: first, revise the bidding rule of the NCDP policy and increase the bid success rate so that more enterprises can win bids, and second, to solve the problem of excessive drug price reduction, evaluate the rationality of bid-winning prices, and introduce a two-way selection mechanism between medical institutions and supply enterprises. Integrate pharmacoeconomic evaluation into the NCDP rules to form a benign competition among enterprises. Third, attention should be paid to supporting policies for small- and medium-sized enterprises. By increasing procurement volume, shortening payment time limits, and increasing the proportion of advance payments, enterprises' cash flow shortages can be alleviated, thus achieving fairness and inclusiveness in the implementation of the NCDP policy.

Analysis of change process of NPP dominated by human activities in Northwest Hubei, China, from 2000 to 2020.

Clarifying the spatial distribution of the impact of different human disturbance activities on the net primary productivity (NPP) in regions with single climatic conditions is of considerable importance to ecological protection. Time-series NPP from 2000 to 2020 was simulated in Northwest Hubei, China, and the effects of the climate and human activities on the NPP changes were separated. Research results showed that from 2000 to 2020, the NPP change with an area of 10,166.63 km2 in Northwest Hubei is influenced by climate and human activities. Among them, human activities account for as high as 84.53%. From 2000 to 2020, the NPP in Northwest Hubei showed a slight upward trend at a rate of 1.61 g C m-2 year-1. The significantly increased NPP accounted for 21.4% of the total, which was mainly distributed in north of Northwest Hubei. And the farming of cultivated land led to the increase of NPP in west as well as the reduced human distribution in cultivated land, which was scattered in forests. Only 6.67% of the total area demonstrated a significantly decreased NPP, which was distributed mainly in the central affected by the expansion of rural-urban land and change of broad-leaved forests to shrubs and in southeast regions of Northwest Hubei caused by the increase in potential evapotranspiration. This study refined the driving factors of spatial heterogeneity of NPP changes in Northwest Hubei, which is conducive to rational planning of terrestrial ecosystem protection measures.

Relationship between negative air ion and PM2.5 in Quercus variabilis under natural conditions.

In recent years, PM2.5 pollution has become a most important source of air pollution. Prolonged exposure to high PM2.5 concentrations can give rise to severe health issues. Negative air ion (NAI) is an important indicator for measuring air quality, which is collectively known as the 'air vitamin'. However, the intricate and fluctuating meteorological conditions and vegetation types result in numerous uncertainties in the correlation between PM2.5 and NAI. In this study, we collected data on NAI, PM2.5, and meteorological elements through positioning observation during the period of June to September in 2019 and 2020 under the condition of relatively constant leaf area in Quercus variabilis forest, a typical forest in warm temperate zones. We investigated the spatiotemporal variation of PM2.5 and NAI under consistent meteorological conditions, established the correlation between PM2.5 and NAI, and explicated the impact mechanism of PM2.5 on NAI in natural conditions. The results showed that NAI decreased exponentially with the increases in natural PM2.5, with a significant negative correlation (y=1148.79x-0.123). The decrease rates of NAI in PM2.5 concentrations of 0-20, 20-40, 40-80, 80-100 and 100-120 µg·m-3 were 40.1%, 36.2%, 9.4%, 2.4%, 5.1% and 6.8%, respectively. Results of the sensitivity analysis showed that the PM2.5 concentration range of 0-40 µg·m-3 was the sensitive range that affected NAI. Our findings could provide a scientific basis for better understanding the response mechanisms of NAI to environmental factors.