Provinces In Eastern China Research Articles

Spatial-temporal evolution mechanism and efficiency evaluation of drought resilience system in China

The frequent occurrence of drought events poses significant challenges to regional sustainable development. Assessing regional drought resilience and efficiency is beneficial for governments to allocate disaster relief funds effectively and assist regions in enhancing their disaster resilience capabilities. In this study, we construct a “social-economic-environmental-institutional” drought resilience assessment framework to reveal the temporal and spatial evolution mechanism and spatial autocorrelation of drought resilience, explore the main factors influencing the evolution of this spatial pattern and the strength and interaction mechanisms among such influencing factors. And build a model from the perspective of input and output, use the SBM-DEA model to evaluate the efficiency of drought resistance, and reveal the spatiotemporal heterogeneity of drought resistance in different regions. The results show that China's drought resilience over the past 10 years has increased by an average index value of 13.14%, showing an overall increasing trend. The drought resilience level of coastal provinces in eastern China is relatively higher, while the resilience level in the inland northwest region is relatively lower. China's drought resilience has significant positive spatial correlation, the development of resilience is in a relatively stable spatial pattern. The H–H aggregation area is distributed in the southeastern coastal area, while the L-L aggregation area is distributed in western China, and the east-west difference is significant. Environmental indicators, such as annual average rainfall and annual average temperature, are the main factors causing spatial differentiation in drought resilience in the China, and the interaction between influencing factors is greater than the impact of a single factor. The drought resilience efficiency of provinces in the inland northwest and southeastern coastal areas is relatively high, while that of provinces in the southwest and northeast is relatively low. China's drought resilience efficiency still needs to be improved. Our research findings offer insights into the development of drought resilience in China, providing support for understanding disaster risk assessment and sustainable development.

Research on the Contribution of Regional Digital Financial inclusion Based on PCA-ANN-MLP Algorithm

Digital Financial Inclusion is a hot topic under the theme of China's economy today. Digital Financial Inclusion is an important supplement and extension of traditional Financial inclusion. Its core idea is to reduce the threshold of financial services and ease the financing difficulties of low-income groups, small and micro enterprises, and other vulnerable groups by providing low-cost and efficient financial services to the public. The empirical results of much literature show that digital Financial inclusion has narrowed the gap between the rich and the poor, which plays a vital role in the high-quality development of China's economy. Therefore, it is important to explore it's influencing factors and analyze the influencing mechanism. This study focuses on the three provinces in eastern China and applies the grounded theory approach. Utilizing data from the Peking University database, 17 factors influencing the level of digital inclusive finance are selected. PCA (principal component analysis) is used to reduce dimensions, and ANN-MLP (artificial neural network multi-layer perceptron) algorithm is used to explore the contribution factors of Digital Financial Inclusion, explore important factors, and put forward relevant suggestions. The significance of this study is that taking the three provinces in eastern China as an example, it explores the factors influencing the development of DFI in China, and makes an important contribution to the issue of how to promote the rapid development of digital Financial inclusion in China.

An Empirical Test of the Influence of Rural Leadership on the Willingness to Participate in Public Affairs from the Perspective of Leadership Identification

The participation of villagers in rural public affairs is vital for the sustainable development of rural communities and the improvement of villagers’ quality of life. Various factors, including individual characteristics, village environment, social forces, and national policies, influence villagers’ willingness to participate. However, empirical research on the determinants of villagers’ participation in public affairs often overlooks the role of grassroots leadership. To address this gap, this study proposes a theoretical model examining the relationship between transformational leadership and villagers’ willingness to participate in public affairs. Using a sample of 438 villagers from Jiangsu Province in eastern China, structural equation modeling and regression are employed to analyze the data. The findings indicate that moral modeling, leadership charm, and personalized care directly impact villagers’ willingness to participate in public affairs or indirectly influence it through leadership identification, which acts as a mediator. Furthermore, shared vision enhances the positive relationship between leadership identification and villagers’ awareness of public affairs participation. These findings provide valuable insights for village cadres seeking to promote active participation in public affairs among villagers. Specifically, gaining recognition through virtuous conduct, capabilities, and strong cadre–villager relationships serves as a foundation for influencing villagers’ willingness to participate in public affairs, while shared vision plays a strategic role in mobilizing villagers based on their identification with leaders.

Water footprint approach in measuring the potential of bioenergy production from agricultural products

Abstract Promoting the supply of energy from biomass to reduce the emission of greenhouse gases has resulted in focusing on the production of important products from the perspective of energy and, ultimately, increasing water consumption. Therefore, in the present study, an index called water footprint was used to investigate the link between water and bioenergy. For this purpose, information related to grain maize crops was collected in the study plains of Fujian Province in eastern China. Based on the calculations, it was found that the water footprint of maize products in the province was equal to 3,728 m3/ton on average, and the water footprint of its biomass was estimated to be 219.6 m3/ton. Moreover, the investigation of the water footprint of maize biomass energy showed that the highest and lowest water footprints per unit of energy are found in Ningde and Zhangzhou, respectively. It was also found that the plains of Zhangzhou, Ningde and Xiamen have little priority for biomass production because the water footprint of their biomass energy is less than 900 MJ/m3. On the other hand, Nanping and Putian plains with bioenergy water footprints between 1,500 and 1,800 MJ/m3 have high priority for using maize biomass for energy production.

Research on identification of the hydraulic and structural vibration sources in a tubular pumping station

The hydraulic and structural vibration sources of pumping station are investigated in current research. Based on a vertical shaft tubular pumping station project in an eastern province of China, a three-dimensional fluid-solid coupling model of the pumping station is established, including the fluid in the flow channel, concrete structure, and hydraulic machinery. Two-way fluid-structure interaction (FSI) method is used to calculate the coupled vibration responses of the pumping station. Based on the FSI simulation results, the hydraulic and structural vibration sources of the pumping station are explored from the frequency perspective based on the Fourier transform theory and the vibration energy transmission perspective based on the time-delayed transfer entropy method. Research results show that the fluid pulsation generated by the rotation of the impeller is the main hydraulic vibration source, and the rotating impeller is the main structural vibration source that causes the vibration of the unit and the concrete structure. This research could provide a scientific basis for structural vibration control, vibration reduction, and isolation design of the pumping station.

Prediction model with multi-point relationship fusion via graph convolutional network: A case study on mining-induced surface subsidence.

Accurate prediction of surface subsidence is of significance for analyzing the pattern of mining-induced surface subsidence, and for mining under buildings, railways, and water bodies. To address the problem that the existing prediction models ignore the correlation between subsidence points, resulting in large prediction errors, a Multi-point Relationship Fusion prediction model based on Graph Convolutional Networks (MRF-GCN) for mining-induced subsidence was proposed. Taking the surface subsidence in 82/83 mining area of Yuandian No. 2 Mine in Anhui Province in eastern China as an example, the surface deformation data obtained from 250 InSAR images captured by Sentinel-1A satellite from 2018 to 2022, combined with GNSS observation data, were used for modeling. The deformation pattern of each single observation point was obtained by feeding their deformation observation data into the LSTM encoder, after that, the relationship graph was created based on the correlation between points in the observation network and MRF-GCN was established. Then the prediction results came out through a nonlinear activation function of neural network. The research shows that the R2R2 value of MRF-GCN model was 0.865 0, much larger than that of Long-Short Term Memory (LSTM) and other conventional models, while mean square error (MSE) of MRF-GCN model was 1.59 899, much smaller than that of LSTM and other conventional models. Therefore, the MRF-GCN model has better prediction accuracy than other models and can be applied to predicting surface subsidence in large areas.

In vitro antifungal susceptibility profile and genotypic characterization of clinical Aspergillus isolates in Eastern China on behalf of Eastern China Invasive Fungi Infection Group.

Aspergillus species is a widespread environmental mould that can cause aspergillosis. The purpose of this study was to investigate the antifungal susceptibility profile and genotypic characterization of clinical Aspergillus isolates from different provinces in Eastern China. The data included the antifungal susceptibility distributions with eight common antifungal drugs, cyp51A gene mutations of triazole-resistant Aspergillus fumigatus sensu stricto, and the genotypic relationships among the A. fumigatus sensu stricto isolates based on microsatellite typing. A. fumigatus sensu lato was the most common clinical Aspergillus species (n=252), followed by A. flavus (n=169), A. terreus (n=37), A. niger (n=29), and A. nidulans (n=4). The modal minimum effective concentration values of micafungin and anidulafungin were lower than those of caspofungin for all Aspergillus species. The in vitro efficacy of isavuconazole was similar to that of voriconazole against most Aspergillus species. Sequencing revealed cyp51A gene mutations TR34/L98H, TR34/L98H/S297T/F495I, and TR46/Y121F/T289A in four triazole-resistant A. fumigatus sensu stricto. Phylogenetic analyses using microsatellite markers of A. fumigatus sensu stricto revealed that 211 unique genotypes clustered into two clades. The data demonstrate the diversity of clinically relevant Aspergillus species in Eastern China. Routine antifungal susceptibility testing should be performed to monitor the antifungal resistance and guide clinical therapy.

Spatial-temporal patterns and influencing factors for pulmonary tuberculosis transmission in China: an analysis based on 15 years of surveillance data.

Profiting from a series of anti-tuberculosis programs in China, the number of tuberculosis (TB) cases has diminished dramatically in the past decades. However, long-term spatial-temporal variations, regional trends of prevalence, and mechanisms of determinant factors remain unclear. Age-period-cohort analysis and Bayesian space-time hierarchy statistics were conducted to identify high-risk populations and areas in mainland China, and the geographical detector model was used to evaluate the important drivers of the disease. The prevalence of pulmonary TB has declined from 73.3/100,000 in 2004 to 55.45/100,000 in 2018. A bimodal distribution was found in age groups, and the birth cohorts before 1978 had relative higher risk. The high-risk areas were mainly distributed in western China and south-central China, and several provinces in eastern China showed a potential increasing trend, including Beijing, Shanghai, Liaoning, and Guangdong province. The index of night light (Q = 0.46), the population density (Q = 0.41), PM10 (Q = 0.38), urbanization rate (Q = 0.32), and PM 2.5 (Q = 0.31) contributed substantially to the spatial distribution of pulmonary tuberculosis. The identifications of epidemic patterns, high-risk areas and influence factors would help design targeted intervention measures to achieve milestones of the end TB strategy.

Relationship between aging population, birth rate and disposable income per capita in the context of COVID-19.

The outbreak of the COVID-19 in early 2020 and the recurring epidemic in later years have disturbed China's economy. Moreover, China's demographic dividend has been disappearing due to its fastest aging population and declining birth rate. The birth rates in eastern provinces of China are much lower than those of the western provinces. Considering the impacts of the COVID-19 and aging population, this paper focused on the relationship between birth rate and the disposable income and tried to find effective measures to raise China's birth rate. We discovered through regression analysis that the link between per capita disposable income and birth rate is initially "reverse J" and later "inverted J", indicating that per capita disposable income will influence the birth rate. Women's employment rate and educational level are negatively correlated with the birth rate. To raise the fertility rate in China, it is necessary to increase the marriage rate and the willingness to have children by raising the per capita disposable income and introducing effective tax relief policies.

On the Colonial Expansion of Tsarist Russia and the Railway Construction in Eastern Province of China

On the Colonial Expansion of Tsarist Russia and the Railway Construction in Eastern Province of China

Dynamical Analyses of a Supercell Tornado in Eastern China Based on a Real-Data Simulation

Tornadoes are extremely destructive natural disasters, and East China has become a high-incidence area for tornadoes in China in recent years. On 7 July 2013, an EF2-intensity tornado occurred in Gaoyou County, Jiangsu Province in eastern China, within a supercell storm near a Meiyu frontal system. To investigate the dynamical process of the tornado, a numerical simulation was performed using four one-way nested grids within the Advanced Regional Prediction System (ARPS). Data from a nearby operational S-band Doppler radar are assimilated using a 4D ensemble Kalman filter (4DEnKF) at 5 min intervals. Forecasts are run with a nested 50 m grid, capturing the tornado embedded within the supercell storm with a reasonable agreement with observations. The tornadogenesis processes within the simulation results are analyzed in detail, including the three-dimensional evolution of the tornado vortex. It is found that a cold surge within the rear flank downdraft region plays a key role in instigating tornadogenesis when the leading edge of the cold surge approaches a near-ground convergence center located underneath the main updraft, and the enhancement of the convergence center caused by the descending of the low-level mesocyclone is the direct cause of the rapid increase in tornado vorticity. Backward trajectories are calculated based on model output, and the origins of the parcels feeding the intensifying tornado vortex are identified. It is found that parcels from the mid-level of the rear flank downdraft region follow the cold surge, descending to the ground under the influence of the downdraft in the cold surge, and then entering the convergence center, merging into the core of the tornado and being lifted up. Vertical profiles of the mass and vorticity fluxes into the core of the tornado vortex are examined, and it is found that the near-ground airflow contributes significantly to the growth of the tornado vorticity, with the contribution increasing as it gets closer to the ground.

Petrophysical Acoustic Characterization of Weathered Granite: A Case Study of Mesozoic Granites in the Coastal Area of Fujian Province, China

In recent years, with the exploration and development of granite buried-hill oil and gas reservoirs, petrophysics research has played an important role in the study of reservoir characteristics and fluid identification. Through analysis of the relationship between the fluid-bearing petrophysical parameters and the reservoir, the seismic response changes caused by reservoir fluid changes can be determined. Mesozoic granites in the coastal area of Fujian Province in eastern China were investigated as the research object of this project. The mineral composition, density, porosity, P-wave velocity, and S-wave velocity of the granite were measured and analyzed by X-ray diffraction, rock density, rock porosity, and rock acoustics methods. Therefore, the granite’s petrophysical properties, fluid response characteristics, and gas sensitivity parameters were analyzed. The result of the study shows that the granite is predominantly monzogranite. According to the type of reservoir space assemblage, the samples can be divided into two types: those containing fracture-dissolution pores and those containing only dissolution pores. All the samples were characterized by medium to high densities and low to extra-low porosity. There was a linear correlation between the P-wave velocity and S-wave velocity under gas and water-saturated conditions. Factors such as P-wave to S-wave velocity ratio, Poisson’s ratio, Lame coefficient, and other parameters of the samples were analyzed, and the threshold values that distinguished the water and gas-saturated states of the samples were measured and determined. In addition, there were negative correlations between the P- and S-wave velocities and porosity. The sensitivities of the petrophysical parameters to the gas capacity from high to low are Ip2 − 2.03 Is2, λ − 0.03 μ, λ, λ/μ, E − 2.03 μ, σ, K/μ, K, Ip, Vp/Vs, Vp, E, μ, Vs, and Is. For granite-buried hill reservoirs, the variation ranges of the parameters, such as the density, porosity, and P-wave velocity, of the fracture-dissolution pore granite samples were larger than those of the dissolution pore samples. The bulk parameters (Ip, Vp, K, λ) and combination parameters (Ip2 − 2.03 Is2, K/μ, λ− 0.03 μ, E − 2.03 μ, λ/μ) of the dissolution pore samples were more sensitive to the gas capacity. The results of this study provide a basis for the geophysical identification of granite-buried hill reservoirs.

The Quantified and Major Influencing Factors on Spatial Distribution of Soil Organic Matter in Provincial-Scale Farmland—A Case Study of Shandong Province in Eastern China

Soil organic matter (SOM) is an important component of soil and plays an important role in improving the soil’s physical and chemical properties. Ascertaining the spatial distribution of soil organic matter and its main controlling factors in the context of provincial scale farming is of important guiding significance for soil carbon sequestration, emission reduction and sustainable utilization. Using 257 soil profiles from the second soil survey in Shandong Province, GIS, we applied geostatistical methods to study the spatial distribution characteristics of SOM in topsoil. In addition, correlation and regression analyses were used to explore the main controlling factors over the spatial variation of SOM. The results showed that the mean amount of SOM in Shandong province ranged from 1.20–74.90 g·kg−1, with a coefficient of variation of 73.52%, which is a medium level of variation. The distribution of SOM in the study area was patchy, with higher levels of organic matter in the central, eastern, and northern parts, and lower levels of organic matter in the south-west. The comprehensive explanatory ability of all factors reached 52.30%. Soil type and parent material were the main controlling factors for the spatial variability of SOM in the Shandong Province, followed by soil texture and land use type, with topography and climatic factors having relatively little influence.

Provincial Maternal and Child Information System in Inner Mongolia, China: Descriptive Implementation Study.

After the implementation of 2- and 3-child policies, the rising proportion of high-age and high-risk pregnancies put enormous pressure on maternal and child health (MCH) services for China. This populous nation with an increasing population flow imperatively required the support of large-scale information systems for management. Municipal MCH information systems were commonly applied in developed cities of eastern provinces in China. However, implementation of provincial MCH information systems in relatively low-income areas is lacking. In 2020, the implementation of a regional maternal and child information system (RMCIS) in Inner Mongolia filled this gap. This paper aimed to demonstrate the construction process and evaluate the implementation effect of an RMCIS in improving the regional MCH in Inner Mongolia. We conducted a descriptive study for the implementation of an RMCIS in Inner Mongolia. Based on the role analysis and information reporting process, the system architecture design had 10 modules, supporting basic health care services, special case management, health support, and administration and supervision. Five-color management was applied for pregnancy risk stratification. We collected data on the construction cost, key characteristics of patients, and use count of the main services from January 1, 2020, to October 31, 2022, in Inner Mongolia. Descriptive analysis was used to demonstrate the implementation effects of the RMCIS. The construction and implementation of the RMCIS cost CNY 8 million (US $1.1 million), with a duration of 13 months. Between 2020 and 2022, the system recorded 221,772 registered pregnant women, with a 44.75% early pregnancy registry rate and 147,264 newborns, covering 278 hospitals and 225 community health care centers in 12 cities. Five-color management of high-risk pregnancies resulted in 76,975 (45.45%) pregnancies stratified as yellow (general risk), 36,627 (21.63%) as orange (relatively high risk), 156 (0.09%) as red (high risk), and 3888 (2.30%) as purple (infectious disease). A scarred uterus (n=28,159, 36.58%), BMI≥28 (n=14,164, 38.67%), aggressive placenta praevia (n=32, 20.51%), and viral hepatitis (n=1787, 45.96%) were the top factors of high-risk pregnancies (yellow, orange, red, and purple). In addition, 132,079 pregnancies, including 65,018 (49.23%) high-risk pregnancies, were registered in 2022 compared to 32,466 pregnancies, including 21,849 (67.30%) high-risk pregnancies, registered in 2020. The implementation of an RMCIS in Inner Mongolia achieved the provincial MCH data interconnection for basic services and obtained both social and economic benefits, which could provide valuable experience to medical administration departments, practitioners, and medical informatics constructors worldwide.

Analysis of Consumers’ Willingness to Pay for Honey in China

Although China is the largest honey producer in the world, domestic consumption is relatively low. Therefore, this study aims to conduct a detailed investigation of honey consumption in the Chinese mainland and identify the main factors determining it. The survey data are from 960 respondents in Jiangxi Province in eastern China. The results showed that respondents mostly prefer an intense flavor (46.46%) and that the color is less important (35.94%). Regarding the types of honey, most respondents prefer runny honey (50.83%) rather than set honey (22.81%). The most common way of buying honey is by a direct sale from beekeepers (44.90%). Most of the respondents have confidence in the quality of domestic honey (87.40%), and the majority consume honey because it is a healthy and nutritious food (74.48%). The results of Fisher’s discriminant analysis indicated that the most important attributes are taste and consistency (of the intrinsic attributes) and price (of the extrinsic attributes), which are the most common reasons for purchasing. These findings provide a better understanding of honey consumption in the Chinese mainland, and they can provide guidance for developing marketing strategies and increasing the level of consumer satisfaction.

Molecular epidemiology analysis of fowl adenovirus detected from apparently healthy birds in eastern China

BackgroundFowl adenovirus is of major concern to the poultry industry worldwidely. In order to monitor the prevalent status of Fowl adenovirus in China, a total of 1920 clinical samples from apparently healthy birds in the 25 sites of poultry flocks, Slaughterhouse and living bird markets from 8 provinces in eastern China were collected and detected by PCR, sequencing, and phylogenetic analysis.ResultsThe epidemiological survey showed that Fowl adenoviruses were detected in living bird markets, and circulating in a variety of fowl species, including chickens, ducks, goose and pigeons. Among the 1920 clinical samples, 166 samples (8.65%) were positive in the fowl adenovirus PCR detection. In this study, totally all the 12 serotypes (serotypes of 1, 2, 3, 4, 5, 6, 7, 8A, 8B, 9, 10 and 11) fowl adenoviruses were detected, the most prevalent serotype was serotype 1. Phylogenetic analysis indicated that 166 FAdVs of 12 serotypes were divided into 5 fowl adenovirus species (Fowl aviadenovirus A, B, C, D, E).ConclusionsIn the epidemiological survey, 8.65% of the clinical samples from apparently healthy birds were positive in the fowl adenovirus PCR detection. Totally all the 12 serotypes fowl adenoviruses were detected in a variety of fowl species, which provided abundant resources for the research of fowl adenoviruses in China. The newly prevalent FAdV serotypes provides valuable information for the development of an effective control strategy for FAdV infections in fowls.

How does the turnover intention of village clinic doctors change after China's new health care system reform? A comparison based on three surveys in a province in eastern China.

This study aims to analyze the changes in village clinic doctors' turnover intention following the new health care system reform (NHCSR). All the data were obtained from three surveys conducted in 2012, 2015, and 2018 in a province in eastern China. Descriptive analysis and analysis of variance (ANOVA) were used to analyze the changes in village clinic doctors' turnover intention. The mean scores of village clinic doctors' turnover intention were 2.87 ± 1.07, 2.76 ± 1.12, and 2.99 ± 1.14 in 2012, 2015, and 2018, respectively, with a significant difference (F = 3.60, P = 0.03). During the 3 years, the turnover intention scores of village clinic doctors who were male, aged 40 years and below, secondary technical school graduates, had the qualifications to practice as village clinic doctors, and were under village-township integrated management first decreased and then increased. The turnover intention scores of village clinic doctors with medical practitioner qualifications increased; however, the scores, decreased for those without village-township integrated management. The turnover intention of village clinic doctors has increased, and the possible reasons for this phenomenon include changes in the demographic characteristics of village clinic doctors and policy factors. The government should pay more attention to the problems that village clinic doctors consider of urgent concern, such as the treatment of income and pension insurance, and provide greater career development and training opportunities for village clinic doctors to maintain their motivation and stability.

Source apportionment of river water pollution in a typical agricultural city of Anhui Province, eastern China using multivariate statistical techniques with APCS–MLR

The deterioration of the surface water environment has become a serious challenge for water resources management due to increasing anthropogenic disturbance. Water resources protection requires control of potential pollution sources. In this study, 99 water samples were collected from a river in a typical agricultural city of Anhui Province in eastern China, and these samples were analyzed in terms of pH, electrical conductivity, and the concentrations of F−, Cl−, SO42−, Na+, K+, Mg2+, Ca2+, As, Cr, Cu, Zn, and Pb. Cluster analysis, co-occurrence network analysis, and principal component analysis/factor analysis were conducted to qualitatively identify the potential sources of river water pollution in the study area. An absolute principal component score–multiple linear regression receptor model was used to quantitatively evaluate the contribution of each source to water quality parameters. The results showed that all observed water quality indices met the quality criteria specified in the Chinese drinking water standards, except for pH, ρ(F−), ρ(SO42−), and ρ(As). The heat map showed that the frequent recharge of pollutants from the tributaries during the wet season was the main reason for the deterioration of water quality. Five sources of river water pollution were identified, and their contribution ratios in a descending order were as follows: the geogenic process (24%) > agricultural activities (21%) > poultry farming sources (17%) > domestic pollution (9%) > transportation pollution (5%). Therefore, controlling pollution from agricultural activities, strengthening the regulation of livestock farming, and improving the sewage network are the recommended strategies for improving the quality of surface water resources in this area.

Characteristics and source apportionment of some halocarbons in Hangzhou, eastern China during 2021

In recent years, eastern China has been identified as an important contributor to national and global emissions of halocarbons, some of which are ozone depletion substances (ODSs) that delay the recovery of the stratospheric ozone layer. However, the most recent characteristics and sources of halocarbons in eastern China remain unclear. Thus, hourly atmospheric observations of halocarbons were conducted in Hangzhou throughout 2021. The results showed that methylene chloride (CH2Cl2) was the most abundant halocarbon (2207 (25 %–75 % quantile: 1116–2848) ppt; parts per trillion) followed by chloromethane (CH3Cl) (912 (683–1043) ppt), and 1,2-dichloroethane (CH2ClCH2Cl) (596 (292–763) ppt). Then, backward trajectory and potential source contribution function (PSCF) analysis show that the emission hot spots of halocarbons were concentrated in adjacent cities in Zhejiang and neighboring provinces in eastern China. Moreover, based on positive matrix factorization (PMF) analysis, industrial emission (38.7 %), solvent usage (32.6 %), and the refrigeration sector and biomass burning (23.7 %) were the main sources of halocarbons (observed in this study). This study reveals high concentrations and potential sources of halocarbons in eastern China, which are important for studying the recovery of the ozone layer.

Molecular surveillance of artemisinin resistance-related Pfk13 and pfcrt polymorphisms in imported Plasmodium falciparum isolates reported in eastern China from 2015 to 2019

BackgroundArtemisinin-based combination therapy (ACT) has been recommended as the first-line treatment by the World Health Organization to treat uncomplicated Plasmodium falciparum malaria. However, the emergence and spread of P. falciparum resistant to artemisinins and their partner drugs is a significant risk for the global effort to reduce disease burden facing the world. Currently, dihydroartemisinin-piperaquine (DHA-PPQ) is the most common drug used to treat P. falciparum, but little evidence about the resistance status targeting DHA (ACT drug) and its partner drug (PPQ) has been reported in Shandong Province, China.MethodsA retrospective study was conducted to explore the prevalence and spatial distribution of Pfk13 and Pfcrt polymorphisms (sites of 72–76, and 93–356) among imported P. falciparum isolates between years 2015–2019 in Shandong Province in eastern China. Individual epidemiological information was collected from a web-based reporting system were reviewed and analysed.ResultsA total of 425 P. falciparum blood samples in 2015–2019 were included and 7.3% (31/425) carried Pfk13 mutations. Out of the isolates that carried Pfk13 mutations, 54.8% (17/31) were nonsynonymous polymorphisms. The mutant alleles A578S, Q613H, C469C, and S549S in Pfk13 were the more frequently detected allele, the mutation rate was the same as 9.7% (3/31). Another allele Pfk13 C580Y, closely associated with artemisinin (ART) resistance, was found as 3.2% (2/31), which was found in Cambodia. A total of 14 mutant isolates were identified in Western Africa countries (45.2%, 14/31). For the Pfcrt gene, the mutation rate was 18.1% (77/425). T76T356 and T76 were more frequent in all 13 different haplotypes with 26.0% (20/77) and 23.4% (18/77). The CVIET and CVIKT mutant at loci 72–76 have exhibited a prevalence of 19.5% (15/77) and 3.9% (3/77), respectively. The CVIET was mainly observed in samples from Congo (26.7%, 4/15) and Mozambique (26.7%, 4/15). No mutations were found at loci 97, 101 and 145. For polymorphisms at locus 356, a total of 24 isolates were identified and mainly from Congo (29.2%, 7/24).ConclusionThese findings indicate a low prevalence of Pfk13 in the African isolates. However, the emergence and increase in the new alleles Pfcrt I356T, reveals a potential risk of drug pressure in PPQ among migrant workers returned from Africa. Therefore, continuous molecular surveillance of Pfcrt mutations and in vitro susceptibility tests related to PPQ are necessary.