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The massive use of antibiotics has led to the escalation of microbial resistance in aquatic environment, resulting in an increasing concern regarding antibiotic resistance genes (ARGs), posing a serious threat to ecological safety and human health. In this study, surface water samples were collected at eight sampling sites along the Yangtze River Estuary. The seasonal and spatial distribution patterns of 10 antibiotics and target genes in two major classes (sulfonamides and tetracyclines) were analyzed. The findings indicated a high prevalence of sulfonamide and tetracycline resistance genes along the Yangtze River Estuary. Kruskal-Wallis analysis revealed significant seasonal variations in the abundance of all target genes. The accumulation of antibiotic resistance genes in the coastal area of the Yangtze River Estuary can be attributed to the influence of urban instream runoff and the discharge of effluents from wastewater treatment plants. ANISOM analysis indicated significant seasonal differences in the microbial community structure. VPA showed that environmental factors contribute the most to ARG variation. PLS-PM demonstrate that environmental factors and microbial communities pose direct effect to ARG variation. Analysis of driving factors influencing ARGs in this study may shed new insights into the mechanism of the maintenance and propagation of ARGs.

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The potentially toxic elements (PTEs), Cu, Pb, Zn, Cd, Cr, Hg and As in the water from the Beibu Gulf, were investigated to reveal the contaminant characteristics and assess the risks to human health. The results showed that the concentration of PTEs in the Beibu Gulf varies significantly both seasonally and spatially, with higher concentrations in summer and in the northern and southern gulf. Terrestrial inputs and local anthropogenic discharge are responsible for the higher level in the northern gulf, and the transportation of water masses is also an important factor for the higher concentrations in the southern gulf. Ecological risk assessment suggested that Hg is the main ecological risk factor. The health risk assessment revealed that dermal exposure to PTEs in the gulf presents potentially carcinogenic health effects for humans. This study provides new insight into the transport of PTEs over a large area of the Beibu Gulf.

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Coastal waters are important sources of volatile halocarbons, which are important in atmospheric chemistry. Here, in May (spring) and October (autumn) 2020, we studied the surface, bottom, and sediment-pore seawater concentrations, atmospheric mixing ratios, and sea-to-air fluxes of the three primary short-lived atmospheric halocarbons (CH3I, CH2Br2, and CHBr3) in the East China Sea (ECS). The highest concentrations of the three short-lived halocarbons occurred in coastal waters, such as the Changjiang estuary and Zhejiang coastal waters, reflecting the influence of excessive anthropogenic inputs on the distributions of these gases. Interestingly, the aqueous levels of these gases seemed to be lower compared to previous measurements in this oceanic region, probably due to reduced contributions from local anthropogenic emission sources. The concentrations of CH3I, CH2Br2, and CHBr3 in pore water were significantly higher than those in bottom water, suggesting that sediment could be a source of these short-lived halocarbons. Additionally, the atmospheric mixing ratios of these gases occasionally increased in coastal areas. An air-mass back trajectory analysis showed this was due to continental anthropogenic sources and emissions from enriched waters. The atmospheric mixing ratios of these halocarbons exhibited significant seasonal variability, with significant correlations among atmospheric CH3I, CH2Br2, and CHBr3 in spring, but not in autumn. The sea-to-air fluxes of CH3I, CH2Br2, and CHBr3 indicated that the ECS is a source of these gases. Seasonal differences in CH3I and CH2Br2 fluxes were driven by changes in wind speed and sea surface temperature, while CHBr3 flux changes were associated with changes in its surface seawater concentration.

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Biomass burning (BB) is an important source of atmospheric persistent organic pollutants (POPs) across the world. However, there are few field-based regional studies regarding the POPs released from BB. Due to the current limitations of emission factors and satellites, the contribution of BB to airborne POPs is still not well understood. In this study, with the simultaneous monitoring of BB biomarkers and POPs based on polyurethane foam-based passive air sampling technique, we mapped the contribution of BB to polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the Indo-China Peninsula. Spearman correlations between levoglucosan and 16 PCBs (rs = 0.264-0.767, p < 0.05) and 2 OCPs (rs = 0.250-0.328, p < 0.05) confirmed that BB may facilitate POP emissions. Source apportionment indicated that BB contributed 9.3% to the total PCB and OCP mass. The high contribution of positive matrix factorization-resolved BB to PCBs and OCPs was almost consistent with their concentration distributions in the open BB season but not completely consistent with those in the pre-monsoon and/or monsoon seasons. Their contribution distributions may reflect the use history and geographic distribution in secondary sources of POPs. The field-based contribution dataset of BB to POPs is significant in improving regional BB emission inventories and model prediction.

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N2O is among the most potent greenhouse gases. In this study, we investigated one of the important N2O production hotspots, the continental margins. We looked at N2O spatiotemporal distributions in situ as well as the potential contributions of nitrification and denitrification to N2O production in sediment cores from the Bohai and South Yellow Seas. Real-time PCR and shotgun metagenomics sequencing were used to analyze the microbial communities related to N2O production. The results showed that N2O concentrations roughly decreased with depth-a trend that was consistent throughout the year and showed no significant seasonal variations. When all the research stations along the continental margin were considered, the estuary exhibited the lowest average N2O concentration. Moreover, nitrification was identified as the main process responsible for N2O production in estuary areas. This study demonstrates that spatial, as opposed to temporal, heterogeneity is the primary factor influencing N2O concentration differences in sediments.

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Neonicotinoid insecticides (NNIs) have been widely used to control insect pests, while their environmental residues and associated hazardous impacts on human and ecosystem health have attracted increasing attention worldwide. In this study, we examined the current levels and associated spatial and temporal patterns of NNIs in multiple environmental media across China. Concentrations of NNIs in surface water, sediment, and soil were in the range of 9.94-755 ng·L-1, 0.07-8.30 ng·g-1 DW, and 0.009-356 ng·g-1 DW, respectively. The high levels of NNIs in surface water, such as in Yangtze River (755 ng·L-1), North River (539 ng·L-1), Nandu River (519 ng·L-1), and Minjiang River (514 ng·L-1), were dominated by imidacloprid, thiamethoxam, and acetamiprid due to their extensive use. The levels of NNIs in sediments were relatively low, and the highest concentration (8.30 ng·g-1 DW) was observed in Dongguan ditch. Sediment-water exchange calculated from fugacity fraction indicated that NNIs in sediment can be released back into the water due to their high solubility and low KOW. Soils from agricultural zones contained the largest residual NNIs, with imidacloprid concentrations in cultivated soil reaching 119 ng·g-1 DW. The calculated leaching potential showed that clothianidin has the highest migration potential to deep soil or groundwater. The monitored data of NNIs presented a decreasing trend from 2016 to 2018, which might be caused by the implementation of relevant control policies for NNI applications. The high levels of NNIs mainly occurred in southern China due to frequent agricultural activities and warm and humid meteorological conditions. The results from this study improve our understanding of the pollution levels and environmental behavior of NNIs in different environmental media across China and provide new knowledge that is needed for making future control policies for NNIs production and application.

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Animal sociality plays a crucial organisational role in evolution. As a result, understanding the factors that promote the emergence, maintenance, and diversification of animal societies is of great interest to biologists. Climate is among the foremost ecological factors implicated in evolutionary transitions in social organisation, but we are only beginning to unravel the possible mechanisms and specific climatic variables that underlie these associations. Ambient temperature is a key abiotic factor shaping the spatio-temporal distribution of individuals and has a particularly strong influence on behaviour. Whether such effects play a broader role in social evolution remains to be seen. In this review, we develop a conceptual framework for understanding how thermal effects integrate into pathways that mediate the opportunities, nature, and context of social interactions. We then implement this framework to discuss the capacity for temperature to initiate organisational changes across three broad categories of social evolution: group formation, group maintenance, and group elaboration. For each category, we focus on pivotal traits likely to have underpinned key social transitions and explore the potential for temperature to affect changes in these traits by leveraging empirical examples from the literature on thermal and behavioural ecology. Finally, we discuss research directions that should be prioritised to understand the potentially constructive and/or destructive effects of future warming on the origins, maintenance, and diversification of animal societies.

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Pan evaporation (EVP) is an important element of the hydrological cycle and exhibits a close relationship with climate change. In this study, the generalized regression neural network (GRNN) model and extreme gradient boosting (Xgboost) model were applied to estimate the monthly EVP. The spatiotemporal distributions of EVP and influencing factors in China and eight subregions from 1961 to 2017 were analyzed. The root mean square error (RMSE) of all GRNN models was approximately 10%, and the Nash-Sutcliffe efficiency (NSE) coefficient was larger than 0.94 in different subregions. The annual mean EVP in all subregions and throughout China showed decreasing trends before 1993, while EVP increasing trends occurred in East China (EC), South China (SC), Southwest China (SWC), west of Northwest China (WNC), and throughout China after 1994. Subsequently, the variable importance in projection (VIP) between EVP and climatic factors obtained by partial least squares (PLS) regression and the relative contribution calculated by Xgboost stepwise regression analysis (SRA) were used to investigate the climatic parameter sensitivity to EVP. The results indicated that the combined effects of the vapor pressure deficit (VPD), sunshine duration (SSD), and wind speed (WIN) were the main reasons for the variations in EVP across China. At the seasonal scale, SSD, WIN, relative humidity (RHU), and VPD were the most sensitive climatic factors to EVP in different seasons. In addition, the Pacific decadal oscillation (PDO) index showed a significant negative correlation with EVP, and the El Niño 3.4 (N3.4) and East Atlantic/Western Russia (EA/WR) indices revealed positive correlations in most regions from 1961 to 1993, while the North Atlantic oscillation (NAO) was negatively correlated with EVP. Moreover, N3.4 and Atlantic multidecadal oscillation (AMO) were positively correlated with EVP from 1994 to 2017. Finally, the yearly number of heatwave events (HWN) was highly correlated with EVP because of the high VPD and SSD levels during the heatwave event periods.

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Coastal heavy metal pollution has become an important topic for seafood safety and marine environmental protection. Unlike toxic heavy metals such as cadmium or chromium, copper is essential for oysters' growth but can inhibit their immune response to exotic stress when going above normal levels. Oysters with high copper levels can easily accumulate and transfer abnormal amounts of copper to upper trophic levels, and generate health risks for humans. This study investigated the spatiotemporal variability and health risk of copper levels in cultured oysters (Crassostrea rivularis) sampled from 23 harbors, bays, or estuaries along the northern South China Sea during 1989-2015. Overall, oyster copper concentrations in the study area ranged from 0.9 to 1897.0 µg/g wet weight with a mean of 210.0 (± 143.6) µg/g and a median of 89.3 µg/g. Although oyster copper levels in the southern China provinces of Guangdong, Guangxi, and Hainan showed an overall decrease during 1989-2015, they stayed relatively low since 1996 and increased slightly after 2010. Oyster copper levels in Guangdong were significantly higher than in Hainan and Guangxi. In Guangdong, oyster copper levels were highest in the Pearl River Estuary, followed by west Guangdong and east Guangdong. The health risk of copper exposure through oyster consumption increased in 2011-2015 compared with in 2006-2010. It is recommended that the human daily intake of cultured oysters in the study area should be reduced by half to minimize copper exposure. This study suggested that copper is one of the most important heavy metal contaminants in coastal and estuarine ecosystems of the northern South China Sea.

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Estuary is an important route for the transport of terrestrial contaminants to the ocean. Its unique hydrodynamic properties may influence the fate and distribution of pollutants. Previous studies have shown that severe pollution because of antibiotics has occurred in many inland surface waterbodies; however, the behavior of antibiotic residuals remains poorly understood in estuarine environments. In this study, the occurrence and spatiotemporal distribution of seven selected antibiotics (i.e., sulfamethazine, sulfamethoxazole, trimethoprim, ofloxacin, ciprofloxacin, erythromycin, and roxithromycin) in a tidal river were investigated through one continuous and four synoptic sampling events. Results show that the concentrations of most antibiotics are in the nanogram per liter level, except for trimethoprim with the highest concentration up to 12,440 ng L-1 during the wet season. Except for sulfamethazine, the other six antibiotics showed high concentrations (i.e., > 100 ng L-1) in at least one sampling campaign. Different temporal distribution patterns of these antibiotics indicated that they were mainly controlled by source loading, flow condition, and discharge amounts. Spatial distribution indicated that the main pollution source of trimethoprim was located in lower reaches, while the other six antibiotics mainly came from the upstream sources. Based on the theoretical dilution line, erythromycin and roxithromycin degraded in the tidal river, whereas the other five types of antibiotics showed a conservative behavior. Tide has important effects on the spatial distribution of antibiotics, especially those with a wide concentration range, in estuarine environments. Furthermore, risk assessment based on the calculated risk quotients showed that five types of antibiotics pose high risks to aquatic organisms. These observations provided new insight into the distribution and transport of common antibiotics in estuarine environments.

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Despite governmental efforts toward the development of policies, funds, and technologies, the inherent characteristics of rural solid waste (RSW) discharge have led to great difficulties in RSW pollution control. However, establishing a realistic management strategy requires greater knowledge of RSW generation. Therefore, the RSW of 72 typical towns and villages from 12 provinces of China was analyzed for physicochemical characteristics, as well as its spatiotemporal distribution. The largest proportion of kitchen waste, coal ash, plastic, and paper of RSW was 33.70% ± 17.87%, 26.50% ± 17.61%, 13.48% ± 5.68%, and 10.75% ± 5.75%, respectively, in 2015. Although RSW had the potential for composting, it was still necessary to pay special attention to heavy metals pollution of RSW. The spatiotemporal distributions of RSW components were extremely non-homogenous, and significant variations existed in the kitchen residue, coal ash, plastic, and paper because of differences in economic growth, climatic changes, dietary habits, energy consumption structure, and consumer preferences. No obvious differences in RSW components were observed between villages and market towns. Overall, RSW treatment and management approaches should be considered based on local conditions of RSW generation.

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In China, ozone pollution shows an increasing trend and becomes the primary air pollutant in warm seasons. Leveraging the air quality monitoring network, a random forest model is developed to predict the daily maximum 8-h average ozone concentrations ([O3]MDA8) across China in 2015 for human exposure assessment. This model captures the observed spatiotemporal variations of [O3]MDA8 by using the data of meteorology, elevation, and recent-year emission inventories (cross-validation R2 = 0.69 and RMSE = 26 µg/m3). Compared with chemical transport models that require a plenty of variables and expensive computation, the random forest model shows comparable or higher predictive performance based on only a handful of readily-available variables at much lower computational cost. The nationwide population-weighted [O3]MDA8 is predicted to be 84 ± 23 µg/m3 annually, with the highest seasonal mean in the summer (103 ± 8 µg/m3). The summer [O3]MDA8 is predicted to be the highest in North China (125 ± 17 µg/m3). Approximately 58% of the population lives in areas with more than 100 nonattainment days ([O3]MDA8>100 µg/m3), and 12% of the population are exposed to [O3]MDA8>160 µg/m3 (WHO Interim Target 1) for more than 30 days. As the most populous zones in China, the Beijing-Tianjin Metro, Yangtze River Delta, Pearl River Delta, and Sichuan Basin are predicted to be at 154, 141, 124, and 98 nonattainment days, respectively. Effective controls of O3 pollution are urgently needed for the highly-populated zones, especially the Beijing-Tianjin Metro with seasonal [O3]MDA8 of 140 ± 29 µg/m3 in summer. To the best of the authors' knowledge, this study is the first statistical modeling work of ambient O3 for China at the national level. This timely and extensively validated [O3]MDA8 dataset is valuable for refining epidemiological analyses on O3 pollution in China.

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Objective: To explore the characteristics regarding temporal, spatial and spatiotemporal distribution on severe fever with thrombocytopenia syndrome (SFTS) in Henan province. Methods: Surveillance data related to SFTS was collected in Henan province, from year 2014 to 2016. Descriptive method was used to analyze the distribution of SFTS. 1.7.0 software related to the Public health geographic information system (PHGIS), was applied to draw the spatial distribution map of SFTS. Chi-square test was used to compare the different incidence rates. Results: A total of 2 781 SFTS cases, including 34 deaths, were reported in Henan province from 2014 to 2016, with an average annual fatality rate as 1.22%. There were statistically significant differences for the incidence rates of SFTS between different years (P<0.01). Cases were mainly concentrated from April to October, which accounted for 96.66% of the total number, with the incidence peak seen in May. Incidence rates of SFTS in spring, summer, autumn were higher than that in winter. The cases were scattering around in 26 counties of 8 cities. Xinyang city reported 2 714 cases, accounting for 97.59% of the total number of cases in the province. The average annual incidence rate in Xinyang city was 17.22 per 100 000, much higher than that for the whole Henan province (0.98 per 100 000), with statistically significant difference (P<0.01). Six counties reported having death cases, that accounted for 23.08% of the total number of counties, reported to have death cases. Two kinds of incidence patterns of SFTS were noticed in Henan province, with aggregation in some local regions or sporadic in individual counties. The number of counties with reporting cases increased annually. The epidemic area was expanding and gradually spreading from south to north areas of the province. Conclusions: SFTS was characterized with both temporal and spatial clusters in Henan province. Effective prevention and control measures should be made in accordance with the spatiotemporal distribution and the trend on SFTS.

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Long-term spatiotemporal trends and health risk assessment of oyster arsenic levels in the coastal waters of northern South China Sea were investigated in order to help improve the quality and safety control and sustainable aquaculture for mollusks in China. Cultured oysters (Crassostrea rivularis) collected from the waters of 23 bays, harbors, and estuaries along the coast of northern South China Sea from 1989 to 2012 were examined for spatial patterns and long-term temporal trends of oyster arsenic levels. Single-factor index and health risk assessment were used to quantify arsenic exposure to human health through oyster consumption. Overall, arsenic was detected in 97.4% of the oyster samples, and oyster arsenic levels were non-detectable-2.51 mg/kg with an average of 0.63 ± 0.54 mg/kg. Oyster arsenic levels in the coastal waters of northern South China Sea showed an overall decline from 1989 to 2012, remained relatively low since 2005, and slightly increased after 2007. Oyster arsenic levels in Guangdong coastal waters were much higher with more variation than in Guangxi and Hainan coastal waters, and the long-term trends of oyster arsenic levels in Guangdong coastal waters dominated the overall trends of oyster arsenic levels in the coastal waters of northern South China Sea. Within Guangdong Province, oyster arsenic levels were highest in east Guangdong coastal waters, followed by the Pearl River estuary and west Guangdong coastal waters. Single-factor index ranged between 0.27 and 0.97, and average health risk coefficient was 3.85 × 10-5, both suggesting that oyster arsenic levels in northern South China Sea are within the safe range for human consumption. However, long-term attention should be given to seafood market monitoring in China and the risk of arsenic exposure to human health through oyster consumption.

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Three-dimensional live cell imaging of the interaction of T cells with antigen-presenting cells (APCs) visualizes the subcellular distributions of signaling intermediates during T cell activation at thousands of resolved positions within a cell. These information-rich maps of local protein concentrations are a valuable resource in understanding T cell signaling. Here, we describe a protocol for the efficient acquisition of such imaging data and their computational processing to create four-dimensional maps of local concentrations. This protocol allows quantitative analysis of T cell signaling as it occurs inside live cells with resolution in time and space across thousands of cells.

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To investigate the environmental fate of 3 main hexabromocyclododecane diastereoisomers (α-, ß-, and γ-HBCDs), samples from various environmental media, including outdoor settled dust, soil, sediment, plant tissues (holly, cypress and pine) and marine species (shrimp, crab and fish) were obtained around an expanded polystyrene material manufacturing plant in Tianjin, China. The 3 main HBCD diastereoisomers were detected with the total concentrations ranging from 328 to 31,752 ng/g dry weight (dw), 2.91-1730 ng/g dw, 23.5-716 ng/g dw, 3.45-2494 ng/g dw, and 0.878-44.8 ng/g dw in the dust, soil, sediment, plant tissues, and marine species, respectively. This indicated that a point source of HBCDs could bring wide impact on its vicinal environment. A significant increasing trend of HBCDs concentrations was noted, as indicated by 12.9-41.6% of increasing rates in total concentrations of HBCDs at four sediment sites in the past five years. The diastereoisomer profiles were sorted into 3 groups: dust, soil and sediment, which had no statistical difference from commercial EPS-products (p > 0.05); plant tissues, which showed a moderate increase of α-isomer (22.9 ± 3.3%); and marine species, which were dominated by α-isomer (62.6 ± 2.8%). For α- and ß-isomers, the results of enantiomeric analysis showed a preferential accumulation of the (+)-enantiomer in part of plant tissues and all marine organisms (p < 0.05). However, there was no enantioselectivity of the 3 isomers in dust, soil, and sediment samples (p > 0.05). Besides, marine food web magnification is observed for HBCDs, with trophic magnification factors close to 2. The daily intakes of HBCDs were estimated to be 0.058-5.84 ng/kg-bw/day for local residents through dust and soil ingestion and 0.048-8.43 ng/kg-bw/day for Tianjin citizens through seafood consumption.

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Objective To explore the characteristics regarding temporal,spatial and spatiotemporal distribution on severe fever with thrombocytopenia syndrome (SFTS) in Henan province.Methods Surveillance data related to SFTS was collected in Henan province,from year 2014 to 2016.Descriptive method was used to analyze the distribution of SFTS.1.7.0 software related to the Public health geographic information system (PHGIS),was applied to draw the spatial distribution map of SFTS.Chi-square test was used to compare the different incidence rates.Results A total of 2 781 SFTS cases,including 34 deaths,were reported in Henan province from 2014 to 2016,with an average annual fatality rate as 1.22％.There were statistically significant differences for the incidence rates of SFTS between different years (P＜0.01).Cases were mainly concentrated from April to October,which accounted for 96.66％ of the total number,with the incidence peak seen in May.Incidence rates of SFTS in spring,summer,autumn were higher than that in winter.The cases were scattering around in 26 counties of 8 cities.Xinyang city reported 2 714 cases,accounting for 97.59％ of the total number of cases in the province.The average annual incidence rate in Xinyang city was 17.22 per 100 000,much higher than that for the whole Henan province (0.98 per 100 000),with statistically significant difference (P＜0.01).Six counties reported having death cases,that accounted for 23.08％ of the total number of counties,reported to have death cases.Two kinds of incidence patterns of SFTS were noticed in Henan province,with aggregation in some local regions or sporadic in individual counties.The number of counties with reporting cases increased annually.The epidemic area was expanding and gradually spreading from south to north areas of the province.Conclusions SFTS was characterized with both temporal and spatial clusters in Henan province.Effective prevention and control measures should be made in accordance with the spatiotemporal distribution and the trend on SFTS.

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Objective To explore the characteristics regarding temporal,spatial and spatiotemporal distribution on severe fever with thrombocytopenia syndrome (SFTS) in Henan province.Methods Surveillance data related to SFTS was collected in Henan province,from year 2014 to 2016.Descriptive method was used to analyze the distribution of SFTS.1.7.0 software related to the Public health geographic information system (PHGIS),was applied to draw the spatial distribution map of SFTS.Chi-square test was used to compare the different incidence rates.Results A total of 2 781 SFTS cases,including 34 deaths,were reported in Henan province from 2014 to 2016,with an average annual fatality rate as 1.22％.There were statistically significant differences for the incidence rates of SFTS between different years (P＜0.01).Cases were mainly concentrated from April to October,which accounted for 96.66％ of the total number,with the incidence peak seen in May.Incidence rates of SFTS in spring,summer,autumn were higher than that in winter.The cases were scattering around in 26 counties of 8 cities.Xinyang city reported 2 714 cases,accounting for 97.59％ of the total number of cases in the province.The average annual incidence rate in Xinyang city was 17.22 per 100 000,much higher than that for the whole Henan province (0.98 per 100 000),with statistically significant difference (P＜0.01).Six counties reported having death cases,that accounted for 23.08％ of the total number of counties,reported to have death cases.Two kinds of incidence patterns of SFTS were noticed in Henan province,with aggregation in some local regions or sporadic in individual counties.The number of counties with reporting cases increased annually.The epidemic area was expanding and gradually spreading from south to north areas of the province.Conclusions SFTS was characterized with both temporal and spatial clusters in Henan province.Effective prevention and control measures should be made in accordance with the spatiotemporal distribution and the trend on SFTS.

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The occurrence and fate of 50 pharmaceuticals and personal care products (PPCPs) were investigated in the surface water of Jiulong River estuary in the southeast of China in spring, wet season, summer, autumn and winter. Results demonstrated a wide distribution of PPCPs in Jiulong River estuary, where 34 PPCPs were detected at least once and 5 PPCPs were detected in all the samples, including caffeine, diclofenac, metoprolol, methyl paraben, and propyl paraben. Spatial and seasonal variations were observed. Special emphasis was placed on the PPCP fate in the estuary. Most PPCPs showed a non-conservative behavior in the estuary, while the non-steroidal anti-inflammatory drugs and bisphenol A showed a pseudo-conservative behavior. The non-conservative and pseudo-conservative behavior was attributed to the combination of the seawater dilution, the introduction of PPCPs via the sewage water, and the physical, chemical, or biological removal processes. Furthermore, PPCP concentrations showed drastic variations in the turbidity maximum zones. To our best knowledge, this is the first work to indicate the pseudo-conservative behavior of PPCPs in the estuary, and to show the drastic variations of PPCPs in the turbidity maximum zone. In addition, the ratio of labile to conservative PPCPs was calculated to track the source of untreated sewage contamination. Results showed a significantly higher ratio compared to the average value in WWTP effluents, indicating the ubiquitous discharge of untreated domestic wastewater in Jiulong River estuary. In addition, the high ratio of bisphenol A to conservative PPCPs implied the potential input of untreated industrial wastewater in Jiulong River estuary.

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Objective To investigate the spatiotemporal expansion and risk factors of scrub typhus (ST) in Shandong,Jiangsu and Anhui provinces.Methods Based on the reported cases in Shandong and Jiangsu from 2006 to 2013,and Anhui from 2008 to 2013 epidemiological characteristics of ST and associated environmental factors were analyzed,using the panel negative binomial regression model.Results A total of 2 968,2 331 and 3 447 ST cases were respectively reported in Shandong,Jiangsu and Anhui during 2006-2013,with the average annual incidence rates as 0.39,0.38 and 0.94 per 100 000 population.Uptrend in Shandong and Jiangsu,but a slight rollback seen in Anhui were observed.Expansion of natural foci was found in the 3 provinces,with affected counties accounted for 38.0％,48.2％ and 46.5％ in Shandong,Jiangsu and Anhui,respectively in 2013.Cases were clustered in autumn but with a peak of single epidemic appeared in October or November,in all the 3 provinces.More female and elderly patients were seen,than in the other age groups,in all the 3 provinces.Majority of the cases were farmers,with an increasing trend in incidence,in all these provinces,followed by housekeepers in Shandong and preschool children in Anhui.The risk factors of transmission in all the 3 provinces were negatively associated with the monthly precipitation,and showing an "inverted-U" pattern in association with monthly temperature.A positive relationship between the risk of transmission and monthly relative humidity was found in Shandong and Jiangsu provinces.However,an "inverted-U" pattern between the risk of transmission and the monthly sunshine hour,appeared in Shandong and Anhui provinces.The incidence of Scrub typhus in Shandong was also positively related to the coverage of forest.Conclusion Surveillance programs and health education measures should focus on the warm and moist areas in all the 3 provinces,and also on forestry areas in Shandong.Health education and prevention on mite-bite should be targeted,especially on high-risk populations as the elderly and farmers,in the 3 provinces.Housekeepers in Shandong and children in Anhui should also be under special concern.