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1.
2.
Environ Monit Assess ; 195(1): 245, 2022 Dec 29.
Article in English | MEDLINE | ID: mdl-36577815

ABSTRACT

The rapid and accurate acquisition of soil property information, especially the soil salinity (SS), is required for saline soil management in the Yellow River Delta (YRD). In this study, Lijin County and Kenli District were selected as study area. Unmanned aerial vehicle (UAV) multispectral data and soil sample data were acquired from March 25 to 28, 2019. Pearson correlation and gray correlation analyses were first used to screen sensitive spectral bands/indices, which were used for model parameters construction. Three machine learning and one statistical analysis methods were used to construct the SS inversion models. The results found that the gray correlation coefficient value were greater than the Pearson coefficient value for all bands and indices. Based on the gray correlation coefficient, nine sensitive bands and indices were selected to construct 18 model parameters. By comparing the 4 models, it was concluded that the BPNN model had the highest inversion accuracy, and its calibration coefficient of determination (R2) and root mean square error (RMSE) were 0.769 and 1.342, respectively. The validation R2 and RMSE were 0.774 and 1.975, respectively, and the relative prediction deviation (RPD) was 2.963. The SS estimation results based on BPNN model were consistent with those of the field investigation. Rapid and accurate inversion of SS based on UAV multispectral technique was achieved in this study, which provides technical support for regional management.


Subject(s)
Environmental Monitoring , Unmanned Aerial Devices , Soil , Rivers , Salinity , China
3.
Emerg Infect Dis ; 28(8): 1703-1707, 2022 08.
Article in English | MEDLINE | ID: mdl-35820171

ABSTRACT

Although reports of human infection with influenza A(H5N6) increased in 2021, reports of similar H5N6 virus infection in poultry are few. We detected 10 avian influenza A(H5N6) clade 2.3.4.4b viruses in poultry from 4 provinces in China. The viruses showed strong immune-escape capacity and complex genetic reassortment, suggesting further transmission risk.


Subject(s)
Influenza A virus , Influenza in Birds , Influenza, Human , Animals , Birds , China/epidemiology , Humans , Influenza A virus/genetics , Influenza in Birds/epidemiology , Influenza, Human/epidemiology , Phylogeny , Poultry , Reassortant Viruses/genetics
4.
Sensors (Basel) ; 22(11)2022 May 25.
Article in English | MEDLINE | ID: mdl-35684611

ABSTRACT

Rapid and large-scale estimation of soil salt content (SSC) and organic matter (SOM) using multi-source remote sensing is of great significance for the real-time monitoring of arable land quality. In this study, we simultaneously predicted SSC and SOM on arable land in the Yellow River Delta (YRD), based on ground measurement data, unmanned aerial vehicle (UAV) hyperspectral imagery, and Landsat-8 multispectral imagery. The reflectance averaging method was used to resample UAV hyperspectra to simulate the Landsat-8 OLI data (referred to as fitted multispectra). Correlation analyses and the multiple regression method were used to construct SSC and SOM hyperspectral/fitted multispectral estimation models. Then, the best SSC and SOM fitted multispectral estimation models based on UAV images were applied to a reflectance-corrected Landsat-8 image, and SSC and SOM distributions were obtained for the YRD. The estimation results revealed that moderately salinized arable land accounted for the largest proportion of area in the YRD (48.44%), with the SOM of most arable land (60.31%) at medium or lower levels. A significant negative spatial correlation was detected between SSC and SOM in most regions. This study integrates the advantages of UAV hyperspectral and satellite multispectral data, thereby realizing rapid and accurate estimation of SSC and SOM for a large-scale area, which is of great significance for the targeted improvement of arable land in the YRD.

5.
mBio ; 13(1): e0337721, 2022 02 22.
Article in English | MEDLINE | ID: mdl-35038906

ABSTRACT

Pathogenic coronaviruses are a major threat to global public health. Here, using a recombinant reporter virus-based compound screening approach, we identified small-molecule inhibitors that potently block the replication of severe acute respiratory syndrome virus 2 (SARS-CoV-2). Among them, JIB-04 inhibited SARS-CoV-2 replication in Vero E6 cells with a 50% effective concentration of 695 nM, with a specificity index of greater than 1,000. JIB-04 showed in vitro antiviral activity in multiple cell types, including primary human bronchial epithelial cells, against several DNA and RNA viruses, including porcine coronavirus transmissible gastroenteritis virus. In an in vivo porcine model of coronavirus infection, administration of JIB-04 reduced virus infection and associated tissue pathology, which resulted in improved weight gain and survival. These results highlight the potential utility of JIB-04 as an antiviral agent against SARS-CoV-2 and other viral pathogens. IMPORTANCE The coronavirus disease 2019 (COVID-19), the disease caused by SARS-CoV-2 infection, is an ongoing public health disaster worldwide. Although several vaccines are available as a preventive measure and the FDA approval of an orally bioavailable drug is on the horizon, there remains a need for developing antivirals against SARS-CoV-2 that could work on the early course of infection. By using infectious reporter viruses, we screened small-molecule inhibitors for antiviral activity against SARS-CoV-2. Among the top hits was JIB-04, a compound previously studied for its anticancer activity. Here, we showed that JIB-04 inhibits the replication of SARS-CoV-2 as well as different DNA and RNA viruses. Furthermore, JIB-04 conferred protection in a porcine model of coronavirus infection, although to a lesser extent when given as therapeutic rather than prophylactic doses. Our findings indicate a limited but still promising utility of JIB-04 as an antiviral agent in the combat against COVID-19 and potentially other viral diseases.


Subject(s)
COVID-19 , SARS-CoV-2 , Chlorocebus aethiops , Humans , Animals , Swine , Antiviral Agents/pharmacology , COVID-19/metabolism , Virus Replication , Vero Cells
6.
J Proteomics ; 248: 104354, 2021 09 30.
Article in English | MEDLINE | ID: mdl-34418579

ABSTRACT

Porcine rotavirus (PoRV), particularly group A, is one of the most important swine pathogens, causing substantial economic losses in the animal husbandry industry. To improve understanding of host responses to PoRV infection, we applied isobaric tags for relative and absolute quantification (iTRAQ) labeling coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to quantitatively identify the differentially expressed proteins in PoRV-infected IPEC-J2 cells and confirmed the differentially accumulated proteins (DAPs) expression differences by performing RT-qPCR and Western blot analysis. Herein, in PoRV- and mock-infected IPEC-J2 cells, relative quantitative data were identified for 4724 proteins, 223 of which were DAPs (125 up-accumulated and 98 down-accumulated). Bioinformatics analyses further revealed that a majority of the DAPs are involved in numerous crucial biological processes and signaling pathways, such as metabolic process, immune system process, amino acid metabolism, energy metabolism, immune system, MHC class I peptide loading complex, Hippo signaling pathway, Th1 and Th2 cell differentiation, antigen processing and presentation, and tubule bicarbonate reclamation. The cellular localization prediction analysis indicated that these DAPs may be located in the Golgi apparatus, nucleus, peroxisomal, cytoplasm, mitochondria, extracellular, plasma membrane, and endoplasmic reticulum (ER). Expression levels of three up-accumulated (VAMP4, IKBKE, and TJP3) or two down-accumulated (SOD3 and DHX9) DAPs upon PoRV infection, were further validated by RT-qPCR and Western blot analysis. Collectively, this work is the first time to investigate the protein profile of PoRV-infected IPEC-J2 cells using quantitative proteomics; these findings provide valuable information to better understand the mechanisms underlying the host responses to PoRV infection in piglets. SIGNIFICANCE: The proteomics analysis of this study uncovered the target associated with PoRV-induced innate immune response or cellular damage, and provided relevant insights into the molecular functions, biological processes, and signaling pathway in these targets. Out of these 223 DAPs, the expression levels of three up-accumulated (VAMP4, IKBKE, and TJP3) and two down-accumulated (SOD3 and DHX9) DAPs upon PoRV infection, have been further validated using RT-qPCR and Western blot analysis. These outcomes could uncover how PoRV manipulated the cellular machinery, which could further our understanding of PoRV pathogenesis in piglets.


Subject(s)
Proteome , Rotavirus , Animals , Cell Line , Chromatography, Liquid , Epithelial Cells , Swine , Tandem Mass Spectrometry
7.
Environ Sci Pollut Res Int ; 28(38): 52887-52900, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34021455

ABSTRACT

The Dawen River Watershed (DRW), an important sub-basin of the Yellow River, has been experiencing substantial climatic and anthropogenic stresses. Identifying how stressors relate to shifts in vegetation growth is critical for maintaining the health and stability of its regional ecosystems. To address this, we constructed a 20-year dataset (1999-2018) reflecting changes in satellite-based normalized difference vegetation index (NDVI), climate variables, and land use in the DRW. We then used time series, principal component, and partial correlation analyses to detect spatial and temporal patterns in vegetation dynamics over time, as well as linkages with temperature, precipitation, and anthropogenic activities. Over 20 years, the DRW exhibited a warming-greening trend and experienced four regime shifts in its climate-vegetation system, roughly centered on 2001, 2006, 2013, and 2016. Both the average and maximum NDVI increased in all seasons, likely due to favorable changes in seasonal climatic conditions. Temperature was the dominant factor promoting vegetative growth in spring, autumn, and throughout the growing season. Precipitation had a considerable positive effect on the average NDVI during the summer. Spatial analyses indicated that 67.94% of the study area exhibited significant increase in NDVI values over time, mainly locating in the mountains and in Dongping County; Significant NDVI decrease was generally located in the urban expansion areas around cities and counties. Land cover types and annual growth cycles appeared to govern spatial patterns and the extent of variation in vegetation growth, followed by land use-related drivers and climate anomalies. These findings offer an insight on appropriate ecological management and climatic adaptation within the Dawen River Watershed.


Subject(s)
Ecosystem , Rivers , China , Climate Change , Environmental Monitoring , Seasons , Temperature
8.
Ying Yong Sheng Tai Xue Bao ; 32(4): 1393-1405, 2021 Apr.
Article in Chinese | MEDLINE | ID: mdl-33899408

ABSTRACT

In recent years, soil salinization in the Yellow River Delta under the effects of hydrology, climate and human activities have become increasingly prominent. Based on the 20 Landsat series images of Hekou, Kenli, Dongying districts and Lijin County of Dongying City selected from 1985 to 2018, numerical regression correction method was used to perform image spectral consistency conversion. The partial least squares regression method was used to construct quantitative inversion models of soil salt content. The soil salt content of the study area were retrieved by the best salt prediction model. The temporal and spatial characteristics of soil salt changes in the Yellow River Delta were analyzed. The results showed that the soil salt inversion model constructed with 10 sensitive spectral indices performed higher prediction accuracy, with coefficient of determination R2=0.769 and RMSE=1.125 for calibration, R2=0.752 and RMSE=1.203 for validation, and relative prediction deviation (RPD)=2.08. Using the measured soil salt data in 2016 to verify the inversion accuracy of the model, the correlation between the measured value and the inverted value was 0.7279. The model was used to map the soil salinity of the Yellow River Delta based on 20 images from 1985 to 2018. The abnormal soil salinity retrieval values was all less than 10%. During the study period, the soil salinity showed an overall trend of rising first and then falling which was lowest in 1985 (3.14 g·kg-1) and highest in 1995 (5.86 g·kg-1). Spatially, the area of heavily saline soil and saline soil in the study area decreased, and that of mildly and moderately saline soil significantly increased (66.6%). The total area of saline soil showed an increasing trend. The effects of hydrological and climatic conditions on soil salinity exhibited hysteresis. The increases of temperature promoted soil salinity, with the relationship between the soil salinity and the average temperatures in the past six months and one year being significantly correlated (R=0.507 and 0.538). Soil salinity did not correlate with regional precipitation, and was most affected by the Yellow River streamflow in the previous season (R=-0.543).


Subject(s)
Rivers , Soil , China , Humans , Hydrology , Salinity , Sodium Chloride
9.
Front Cell Dev Biol ; 9: 736649, 2021.
Article in English | MEDLINE | ID: mdl-35111745

ABSTRACT

Recent studies have reported that T-cell differentiation protein 2 (MAL2) is an important regulator in cancers. Here, we downloaded data from multiple databases to analyze MAL2 expression and function in pan-cancers, especially in ovarian cancer (OC). Gene Expression Profiling Interactive Analysis (GEPIA) databases was used to examine MAL2 expression in 13 types of cancer. Kaplan-Meier plotter database was used to analyze the overall survival rate of MAL2 in pan-cancers. The Catalog of Somatic Mutations in Cancer (COSMIC), cBioPortal, and UCSC databases were used to examine MAL2 mutation in human cancers. Metascape, STRING, and GeneMANIA websites were used to explore MAL2 function in OC. Furthermore, ggplot2 package and ROC package were performed to analyze hub gene expression and undertake receiver operating characteristic (ROC) analysis. Drug sensitivity of MAL2 in OC was examined by the GSCALite database. In order to verify the results from databases above, real-time quantitative polymerase chain reaction (qRT-PCR) and western blotting were conducted to detect the expression of MAL2 in OC cells. CRISPR/Cas9 system was used to knockout the MAL2 gene in the OC cell lines HO8910 and OVCAR3, using specific guide RNA targeting the exons of MAL2. Then, we performed proliferation, colony formation, migration, and invasion assays to investigate the impact of MAL2 in OC cell lines in vivo and in vitro. Epithelial-mesenchymal transition (EMT)-associated biomarkers were significantly altered in vitro via western blotting and qRT-PCR. Taken together, we observed that MAL2 was remarkably dysregulated in multiple cancers and was related to patient overall survival (OS), mutation, and drug sensitivity. Furthermore, experimental results showed that MAL2 deletion negatively regulated the proliferation, migration, invasion, and EMT of OC, indicating that MAL2 is a novel oncogene that can activate EMT, significantly promote both the proliferation and migration of OC in vitro and in vivo, and provide new clues for treatment strategies.

10.
bioRxiv ; 2021 Jun 04.
Article in English | MEDLINE | ID: mdl-32995798

ABSTRACT

Pathogenic coronaviruses represent a major threat to global public health. Here, using a recombinant reporter virus-based compound screening approach, we identified several small-molecule inhibitors that potently block the replication of the newly emerged severe acute respiratory syndrome virus 2 (SARS-CoV-2). Among them, JIB-04 inhibited SARS-CoV-2 replication in Vero E6 cells with an EC50 of 695 nM, with a specificity index of greater than 1,000. JIB-04 showed in vitro antiviral activity in multiple cell types against several DNA and RNA viruses, including porcine coronavirus transmissible gastroenteritis virus. In an in vivo porcine model of coronavirus infection, administration of JIB-04 reduced virus infection and associated tissue pathology, which resulted in improved weight gain and survival. These results highlight the potential utility of JIB-04 as an antiviral agent against SARS-CoV-2 and other viral pathogens.

11.
PLoS One ; 15(8): e0237878, 2020.
Article in English | MEDLINE | ID: mdl-32833966

ABSTRACT

Land subsidence monitoring provides information required when developing land use plans and allows for proactive management of subsidence issues. However, it has been challenging to accurately detect land subsidence areas, especially those under waterbodies. This study evaluated the applicability of integrated use of the optical Landsat-8 OLI and microwave Sentinel-1A TOPSAR imagery to delineate subsidence areas and quantify subsidence rates in a typical coal mining area of North China Plain. An Enhanced Modified Normalized Difference Water Index (E-MNDWI) was combined with Short BAseline Subset-Interferometric Synthetic Aperture Radar (SBAS-InSAR) image to monitor underwater and dry ground subsidence. The results demonstrated that the method could delineate underwater and dry ground subsidence and quantify its rates accurately. The proposed method estimated subsidence area corresponded to 34.8% (16.7 km2) of the study area. The size of underwater subsidence areas was substantial and accounted for 43.7% of the subsidence areas. Seasonal underwater subsidence areas were generally distributed in the vicinity of perennial ones. Dry ground subsidence covered 9.4 km2 of the study area and generally occurred in urban and rural residential areas with the maximum subsidence of up to 80.1 mm/year. This study demonstrates the efficiency and capacity of integrating optical and microwave images to monitor the subsidence progresses, which thus can help develop effective rehabilitation policy and strategy to mitigate the impacts of land subsidence.


Subject(s)
Environmental Monitoring , Groundwater , China , Geography , Microwaves , Optical Imaging , Remote Sensing Technology , Satellite Imagery
12.
Transbound Emerg Dis ; 67(3): 1364-1370, 2020 May.
Article in English | MEDLINE | ID: mdl-31793242

ABSTRACT

From 2010, porcine epidemic diarrhea virus (PEDV) variants caused sequential outbreaks of disease in Asia and the United States. In this retrospective study, 49 complete spike (S) gene sequences were obtained from PEDV strains collected in China from 2014 to 2016. We observed that variant PEDV strains with novel insertions, deletions, and multiple S gene recombination types were present in China. In addition, mixed infections involving different variant strains were observed in some areas. Based on phylogenetic and recombination analyses, we determined that the newly emerged PEDV variants potentially originated via recombination between the earliest Chinese G1 genogroup strain, JS-2004-2 and earlier Korean pandemic strains. These findings provide important information for understanding ongoing PEDV outbreaks and suggest that novel variants make it more difficult to prevent PEDV infection.


Subject(s)
Coronavirus Infections/veterinary , Porcine epidemic diarrhea virus/genetics , Swine Diseases/virology , Animals , China/epidemiology , Coronavirus Infections/epidemiology , Coronavirus Infections/virology , Disease Outbreaks/veterinary , Genotype , Phylogeny , Retrospective Studies , Swine , Swine Diseases/epidemiology
13.
Vet Microbiol ; 239: 108455, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31767073

ABSTRACT

Clathrin-mediated endocytosis is a mechanism used for the invasion of cells by a variety of viruses. Mortalin protein is involved in a variety of cellular functions and plays a role in viral infection. In this study, we found that mortalin significantly inhibited the replication of porcine epidemic diarrhea virus (PEDV) through restricting virus entry. Mechanistically, a biochemical interaction between the carboxyl terminus of mortalin and clathrin heavy chain (CLTC) was been found, and mortalin could induce CLTC degradation through the proteasomal pathway, thereby inhibiting the clathrin-mediated endocytosis of PEDV into host cells. In addition, artificial changes in mortalin expression affected the cell entry of transferrin, further confirming the above results. Finally, we confirmed that this host-mounted antiviral mechanism was broadly applicable to other viruses, such as vesicular stomatitis virus (VSV), rotavirus (RV), and transmissible gastroenteritis virus (TGEV), which use the same clathrin-mediated endocytic to entry. These results reveal a new function of mortalin in inhibiting endocytosis, and provide a novel strategy for treating PEDV infections.


Subject(s)
Clathrin/metabolism , Endocytosis/physiology , HSP70 Heat-Shock Proteins/metabolism , Host Microbial Interactions/physiology , Porcine epidemic diarrhea virus/physiology , Virus Internalization , Virus Replication/physiology , Animals , Cell Line , Chlorocebus aethiops , Down-Regulation/physiology , Gene Silencing , HSP70 Heat-Shock Proteins/genetics , HeLa Cells , Humans , RNA, Small Interfering/metabolism , Vero Cells
14.
Environ Sci Pollut Res Int ; 26(28): 28817-28828, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31377928

ABSTRACT

A review of energy subsidy research from a bibliometric perspective was conducted. Based on the bibliometric method, a statistical analysis of energy subsidy-related publications from 1997 to 2016 was undertaken using the Science Citation Index (SCI) and Social Science Citation Index (SSCI) databases. A total of 1182 publications were retrieved, with a significant increase in the number of publications observed after 2006. The majority of these publications were within the disciplines of Energy & Fuels and Environmental Science & Ecology. Although the USA and China contributed the most papers, authors from 96 countries were involved in the various studies. The USA was the center of global collaborations, while other countries/territories mainly conducted bilateral or regional collaborations in their research activities. Five of the top 11 most productive institutes were from China, followed by the USA. The frequency of collaborations among institutes was relatively low. However, the institute-keyword 2-mode network showed that institutes had great potential to cooperate on a number of common topics. Five major themes were identified from the co-keywords analysis: general renewable energy research, bio-energies, sustainability, subsidies, and welfare. The findings, as a complement to previous conventional reviews, will be useful in future energy subsidy research.


Subject(s)
Publications/statistics & numerical data , Renewable Energy , Bibliometrics , China , Databases, Factual , Humans
15.
Sci Total Environ ; 663: 198-205, 2019 May 01.
Article in English | MEDLINE | ID: mdl-30711586

ABSTRACT

Domestic trade flourishes with economic development and the spatial separation of production and consumption. Therefore, the prosperity of trade is accompanied by the transfer of pollution from the demand side to the supply side, which could potentially worsen the environmental quality of the supply side. Despite a large number of studies on the pollution haven hypothesis in international trade, little attention has been paid to testing the hypothesis in domestic trade. Here, combining a multiregional input-output analysis and a gravity model of trade in China, we provide an empirical test to address this problem for the first time. We also assess the factors affecting the SO2 emissions embodied in trade, including population, economic development, coal consumption, distance, and environmental regulations. We found that domestic trade contributed approximate one third of the total SO2 emissions in China, and interprovincial transfers of SO2 embodied in trade were significantly determined by the population, economic development, coal consumption of the trade pairs, as well as their distance. SO2 emission mitigation policies, such as emission reduction target and sulfur dioxide control zone, has a more significant influence on the direct transfer of SO2 emission via direct bilateral trade, while their effects were largely offset by indirect trade (through third-party transfers). Our results do not support the pollution haven hypothesis existed in domestic trade in China during 2007-2012. Our paper sets an example and provides a reference for the domestic pollution transfer problem from an econometric perspective. Further attempts on testing pollution haven hypothesis in consideration of various pollutants are still needed to arrive at a robust conclusion.

17.
PLoS One ; 13(4): e0196198, 2018.
Article in English | MEDLINE | ID: mdl-29677214

ABSTRACT

Coal mining has led to increasingly serious land subsidence, and the reclamation of the subsided land has become a hot topic of concern for governments and scholars. Soil quality of reclaimed land is the key indicator to the evaluation of the reclamation effect; hence, rapid monitoring and evaluation of reclaimed land is of great significance. Visible-near infrared (Vis-NIR) spectroscopy has been shown to be a rapid, timely and efficient tool for the prediction of soil organic carbon (SOC). In this study, 104 soil samples were collected from the Baodian mining area of Shandong province. Vis-NIR reflectance spectra and soil organic carbon content were then measured under laboratory conditions. The spectral data were first denoised using the Savitzky-Golay (SG) convolution smoothing method or the multiple scattering correction (MSC) method, after which the spectral reflectance (R) was subjected to reciprocal, reciprocal logarithm and differential transformations to improve spectral sensitivity. Finally, regression models for estimating the SOC content by the spectral data were constructed using partial least squares regression (PLSR). The results showed that: (1) The SOC content in the mining area was generally low (at the below-average level) and exhibited great variability. (2) The spectral reflectance increased with the decrease of soil organic carbon content. In addition, the sensitivity of the spectrum to the change in SOC content, especially that in the near-infrared band of the original reflectance, decreased when the SOC content was low. (3) The modeling results performed best when the spectral reflectance was preprocessed by Savitzky-Golay (SG) smoothing coupled with multiple scattering correction (MSC) and first-order differential transformation (modeling R2 = 0.86, RMSE = 2.00 g/kg, verification R2 = 0.78, RMSE = 1.81 g/kg, and RPD = 2.69). In addition, the first-order differential of R combined with SG, MSC with R, SG together with MSC and R also produced better modeling results than other pretreatment combinations. Vis-NIR modeling with specific spectral preprocessing methods could predict SOC content effectively.


Subject(s)
Carbon/analysis , Soil/chemistry , Spectroscopy, Near-Infrared/methods , China , Coal Mining , Least-Squares Analysis , Models, Statistical
18.
Sci Total Environ ; 578: 542-550, 2017 Feb 01.
Article in English | MEDLINE | ID: mdl-27847182

ABSTRACT

The Western Jianghan Plain (WJHP) lies in the middle reaches of the Yangtze River. It has been impacted by anthropogenic activities during the past decades. The long-term variations of the WJHP's regional aquifer's hydrochemistry and groundwater quality have not been previously assessed. Sixteen physiochemical parameters at 29 monitoring wells within the Western Jianghan Plain were monitored during 1992-2010 and analyzed with multiple approaches. The confined groundwater is predominantly of the HCO3-Ca-Mg type with Cl-, SO42-, NH4-N, and NO3-N showing remarkable spatial variations. Correlation analysis was used to identify the origins and contamination sources of groundwater. The seasonal Mann-Kendall test revealed that pH, NO3-N, and Cl- concentrations at 27, 26 and 15 wells, respectively, exhibited significant increasing trends during 1992-2010. The increase of pH may be attributed to CO2 degassing caused by extensive groundwater extraction. Regional average NO3-N concentrations of groundwater increased coincidently with the increased use of fertilizer, which suggests that nitrate pollution is caused by agricultural activities. Abnormally high values of Cl- and SO42- at some wells were induced by industrial chemicals. In addition, the similarity of the temporal variations of the regional average of pH, NH4-N, and NO3-N concentrations in groundwater with those in the Yangtze River at the outlet of the Three Gorges Reservoir (TGR) suggests that the variations of these parameters in the WJHP is partly due to water storage by the TGR. This study presents an analysis of temporal variations of groundwater quality in the WJHP that reveals a relation between the creation of the TGR and downstream groundwater quality. This paper's findings provide clues for measures that could be taken to protect the groundwater quality of the WJHP's aquifer.


Subject(s)
Environmental Monitoring , Groundwater/chemistry , Nitrates/analysis , Water Pollutants, Chemical/analysis , China , Time Factors , Water Pollution , Water Wells
19.
Carbohydr Polym ; 130: 364-71, 2015 Oct 05.
Article in English | MEDLINE | ID: mdl-26076637

ABSTRACT

The removal of bisphenol-AF (BPAF) from aqueous solutions onto chitosan-modified zeolite (Ch-Z) in the absence and presence of sodium cholate (NaC) was investigated. It was found that NaC significantly increased the adsorption capacity of Ch-Z for BPAF. At an initial concentration of 100 µmol/L, the removal of BPAF by adsorption onto Ch-Z with NaC was more than ninefold higher than without NaC, and the maximum removal was achieved at a Ch-Z dosage of 1g/L with a NaC concentration of 1.68 mmol/L. Besides, batch studies were performed to evaluate the effects of various experimental parameters on the removal of BPAF. Kinetic studies and adsorption isotherms indicated that the adsorption process of BPAF onto Ch-Z with NaC could be expressed by a pseudo second-order model and the Freundlich isotherm model, respectively. For the enhanced removal, an interaction mechanism was proposed involving the co-effect of BPAF and NaC adsorbed onto Ch-Z.


Subject(s)
Benzhydryl Compounds/chemistry , Benzhydryl Compounds/isolation & purification , Chitosan/chemistry , Phenols/chemistry , Phenols/isolation & purification , Sodium Cholate/chemistry , Water Pollutants, Chemical/analysis , Water Purification/methods , Zeolites/chemistry , Adsorption , Hydrogen-Ion Concentration , Kinetics , Thermodynamics
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