PFASs in China's soils: Temporal declines in legacy compounds mask rising threats from substitutes.

Prunus conradinae (subgenus Cerasus, Rosaceae) is a significant germplasm resource of wild cherry blossom in China. To ensure the comprehensiveness of this study, we used a large sample size (12 populations comprising 244 individuals) which involved the fresh leaves of P. conradinae in Eastern, Central, and Southwestern China. We combined morphological and molecular evidence (three chloroplast DNA (cpDNA) sequences and one nuclear DNA (nr DNA) sequence) to examine the population of P. conradinae variation and differentiation. Our results revealed that Central, East, and Southwest China are important regions for the conservation of P. conradinae to ensure adequate germplasm resources in the future. We also found support for a new variant, P. conradinae var. rubrum. We observed high genetic diversity within P. conradinae (haplotype diversity [Hd] = 0.830; ribotype diversity [Rd] = 0.798), with novel genetic variation and a distinct genealogical structure among populations. There was genetic variation among populations and phylogeographic structure among populations and three geographical groups (Central, East, and Southwest China). The genetic differentiation coefficient was the lowest in the Southwest region and the gene exchange was obvious, while the differentiation was obvious in Central China. In the three geographic groups, we identified two distinct lineages: an East China lineage (Central China and East China) and a Southwest China lineage ((Central China and Southwest China) and East China). These two lineages originated approximately 4.38 million years ago (Mya) in the early Pliocene due to geographic isolation. P. conradinae expanded from Central China to East China at 3.32 Mya (95% HPD: 1.12-5.17 Mya) in the Pliocene. The population of P. conradinae spread from East China to Southwest China, and the differentiation time was 2.17 Mya (95% (HPD: 0.47-4.54 Mya), suggesting that the population of P. conradinae differentiated first in Central and East China. The population of P. conradinae experienced differentiation from Central China to Southwest China around 1.10 Mya (95% HPD: 0.11-2.85 Mya) during the early Pleistocene of the Quaternary period. The southeastern region of East China, near Mount Wuyi, likely serves as a refuge for P. conradinae. This study establishes a theoretical foundation for the classification, identification, conservation, and exploitation of germplasm resources of P. conradinae.

Objective: To explore the influencing factors of pregnancy-induced hypertensive disorders in pregnancy (HDP) with organ or system impairment in pregnant women, and to analyze and compare the differences of HDP subtypes in different regions of China. Methods: A total of 27 680 pregnant women with HDP with complete data from 161 hospitals in 24 provinces, autonomous regions and municipalities were retrospectively collected from January 1, 2018 to December 31, 2018. According to their clinical manifestations, they were divided into hypertension group [a total of 10 308 cases, including 8 250 cases of gestational hypertension (GH), 2 058 cases of chronic hypertension during pregnancy] and hypertension with organ or system impairment group [17 372 cases, including 14 590 cases of pre-eclampsia (PE), 137 cases of eclampsia, 2 645 cases of chronic hypertension with PE]. The subtype distribution of HDP in East China (6 136 cases), North China (4 821 cases), Central China (3 502 cases), South China (8 371 cases), Northeast China (1 456 cases), Southwest China (2 158 cases) and Northwest China (1 236 cases) were analyzed. By comparing the differences of HDP subtypes and related risk factors in different regions, regional analysis of the risk factors of HDP pregnant women with organ or system impairment was conducted. Results: (1) The proportions of HDP pregnant women with organ or system impairment in Northeast China (79.05%, 1 151/1 456), Central China (68.42%, 2 396/3 502) and Northwest China (69.34%, 857/1 236) were higher than the national average (62.76%, 17 372/27 680); the proportions in North China (59.18%, 2 853/4 821), East China (60.85%, 3 734/6 136) and South China (59.56%, 4 986/8 371) were lower than the national average, and the differences were statistically significant (all P<0.05). (2) Univariate analysis showed that the proportions of primiparas, non-Han, non-urban household registration, irregular prenatal examination and PE history in the hypertension with organ or system impairment group were higher than those in the hypertension group, and the differences were statistically significant (all P<0.05). Multivariate logistic regression analysis showed that primiparas, non-Han, non-urban household registration, irregular prenatal examination and PE history were independent risk factors for HDP pregnant women with organ or system impairment (all P<0.05). (3) Primipara: the rates of primipara in Northeast China, North China and Southwest China were higher than the national average level, while those in South China, Central China and Northwest China were lower than the national average level. Non-Han nationality: the rates of non-Han nationality in Northeast China, North China and Northwest China were higher than the national average, while those in East China, South China and Central China were lower than the national average. Non-urban household registration: the rates of non-urban household registration in Northeast China, North China, and Southwest China were lower than the national average, while those in East China, Central China were higher than the national average. Irregular prenatal examination: the rates of irregular prenatal examination in North China, South China and Southwest regions were lower than the national average level, while those in Northeast China, Central China and Northwest China were higher than the national average level. History of PE: the incidence rates of PE in Northeast China, North China, South China and Southwest China were lower than the national average level, while those in Central China and Northwest China were higher than the national average level. Conclusions: Primiparas, non-Han, non-urban household registration, irregular prenatal examination, and PE history are risk factors for HDP pregnant women with organ or system impairment. Patients in Northeast, Central and Northwest China have more risk factors, and are more likely to be accompanied by organ or system function damage. It is important to strengthen the management of pregnant women and reduce the occurrence of HDP.

Crop water footprints and their driving mechanisms show regional differences

A Cross-Sectional Nationwide Study on Accessibility and Availability of Neonatal care Resources in Hospitals of China: Current Situation, Mortality and Regional Differences: Neonatal Care Resources and Newborn Mortality in China.

Local and inter-regional contributions to PM2.5 nitrate and sulfate in China

Distribution profiles of per- and poly fluoroalkyl substances (PFASs) and their re-regulation by ocean currents in the East and South China Sea

BackgroundThe epidemiological features of Guillain-Barré syndrome (GBS) were different in different areas; a comparison of the disease was needed to identify the variation and prognosis. We compare the epidemiological features of GBS in different areas in China.MethodA total of 1,191 patients were included. Information was collected in patients diagnosed with GBS and its variants in middle and south China, and then retrospectively reviewed. The patients were divided into four different regions: East China (n = 441), Center China (n = 566), South China (n = 77), and Southwest China (n = 107). These subregions are mainly divided by climate and geographical location. These data were compared with data from a study in East China (Shandong, n = 150) and Northeast China (Changchun, n = 750).ResultsPatients from the south and southwest China were younger than other regions (P = 0.000). A summer peak and an autumn peak were found in northern China, but more patients in winter and spring days in other areas (P = 0.000). Upper respiratory tract infection (URTI) was the preceding event of GBS patients in all regions but rarer in central China (P = 0.001). The proportion of axonal subtype was higher in central and southwest China than in other regions (P = 0.001). Patients in southwest China were more served at nadir and have the longest hospital stay (P = 0.003 and P = 0.000).ConclusionThe difference between seasonal variation and preceding events was found in different regions in China; clinical features differ among regions in China.

Perfluoroalkyl acids (PFAAs) in the aquatic food web of a temperate urban lake in East China: Bioaccumulation, biomagnification, and probabilistic human health risk

Black carbon pollution in China from 2001 to 2019: Patterns, trends, and drivers

With the acceleration of urbanization, ozone (O3) pollution has become increasingly serious in many Chinese cities. This study analyzes the temporal and spatial characteristics of O3 based on monitoring and meteorological data for 366 cities and national weather stations throughout China from 2016 to 2020. Least squares linear regression and Spearman’s correlation coefficient were computed to investigate the relationships of O3 with various pollution factors and meteorological conditions. Global Moran’s I and the Getis–Ord index Gi* were adopted to reveal the spatial agglomeration of O3 pollution in Chinese cities and characterize the temporal and spatial characteristics of hot and cold spots. The results show that the national proportion of cities with an annual concentration exceeding 160 μg·m−3 increased from 21.6% in 2016 to 50.9% in 2018 but dropped to 21.5% in 2020; these cities are concentrated mainly in Central China (CC) and East China (EC). Throughout most of China, the highest seasonal O3 concentrations occur in summer, while the highest values in South China (SC) and Southwest China (SWC) occur in autumn and spring, respectively. The highest monthly O3 concentration reached 200 μg·m−3 in North China (NC) in June, while the lowest value was 60 μg·m−3 in Northeast China (NEC) in December. O3 is positively correlated with the ground surface temperature (GST) and sunshine duration (SSD) and negatively correlated with pressure (PRS) and relative humidity (RHU). Wind speed (WIN) and precipitation (PRE) were positively correlated in all regions except SC. O3 concentrations are significantly differentiated in space: O3 pollution is high in CC and EC and relatively low in the western and northeastern regions. The concentration of O3 exhibits obvious agglomeration characteristics, with hot spots being concentrated mainly in NC, CC and EC.

The types, grades and distribution features of geoheritage in China: An inventory

Spatial-temporal characteristics and transfer modes of rural homestead in China

The burning of crop residues emits large quantities of atmospheric aerosols. Published studies have developed inventories of emissions from crop residue burning based on statistical data. In contrast, this study used satellite-retrieved land-cover data (1 km × 1 km) as activity data to compile an inventory of atmospheric pollutants emitted from the burning of crop residues in China in {dy2015}. The emissions of PM10, PM2.5, VOCs, NOx, SO2, CO, and NH3 from burning crop straw on nonirrigated farmland in China in 2015 were 610.5, 598.4, 584.4, 230.6, 35.4, 3329.3, and 36.1 Gg (1 Gg = 109 g), respectively; the corresponding emissions from burning paddy rice residues were 234.1, 229.7, 342.3, 57.5, 57.5, 1122.1, and 21.5 Gg, respectively. The emissions from crop residue burning showed large spatial and temporal variations. The emissions of particulate matter and gaseous pollutants from crop residue burning in nonirrigated farmland were highest in east China, particularly in Shandong, Henan, Anhui, and Sichuan provinces. Emissions from burning paddy rice residue were highest in east and central China, with particularly high levels in Shandong, Jiangsu, Zhejiang, and Hunan provinces. The monthly variations in atmospheric pollutant emissions were similar among different regions, with the highest levels observed in October in north, northeast, northwest, east, and southwest China and in June and July in central and south China. The developed inventory of emissions from crop residue burning is expected to help improve air quality models by providing high-resolution spatial and temporal data.

This study focuses on 55 shrinking cities selected by the urban shrinkage index using data about the urban population of 250 prefecture-level Chinese cities from 2012 to 2017. It analyzes the theoretical impacts of urban shrinkage on haze pollution and the spatial distribution and autocorrelation of urban shrinkage. The spatial error model (SEM) and the fully modified least squares (FMOLSs) regression are used to empirically examine the impacts of urban shrinkage on haze pollution at national and regional levels. The results indicate that shrinking cities showed spatial agglomeration and that northeast China had the largest number of shrinking cities. Nationwide, urban shrinkage reduced haze pollution. An increase in the proportion of secondary industries, economic development, and built-up areas intensified haze pollution, while an increase in the green area in parks alleviated such pollution. Regionally, except for west China, the impacts of urban shrinkage on haze pollution were significantly negative. Urban shrinkage in central China had the greatest impacts on haze, followed by northeast China and east China. Haze pollution was intensified by the increase in the proportion of secondary industries in east, central and west China, alleviated by economic development in east and west China, slowed down by the increase in green area in parks in northeast, east and west China, and aggravated by the rise in built-up areas in northeast, central, and west China. Targeted suggestions are proposed herein to reduce haze pollution, adapt to urban shrinkage and build quality small cities based on local conditions.

Per- and polyfluoroalkyl substances (PFAS) are a large family of synthetic fluorinated chemicals. Studies using multiple analytical approaches to evaluate PFAS-contaminated soils are still limited, potentially leading to an underestimation of PFAS pollution. This study introduced a stepwise analytical workflow for a comprehensive assessment of organofluorine, integrating total fluorine (TF) determination, extractable organofluorine (EOF) analysis, PFAS target analysis, and PFAS precursor oxidative conversion assay. The workflow was applied to ten field soil samples collected from aqueous film-forming foam (AFFF)-contaminated sites. The sum target PFAS concentration (∑PFAS) ranged from 51.8 to 23200ng/g dry weight. Perfluorooctanesulfonic acid was the predominant PFAS, accounting for 13%-82% (mean value: 53%) of the ∑PFAS. Target PFAS accounted for 1%-80% of the EOF in the soil samples, and the integration of oxidative conversion revealed additional EOF contributions ranging from 0% to 31%. However, a considerable proportion (20%-94%) of unknown organofluorine still persists after combining targeted PFAS analysis and oxidative conversion, likely due to non-oxidizable PFAS, incomplete conversion of unknown PFAS precursors, and persistence of ultra-short chain PFAS post oxidative conversion. In addition, a significant positive correlation was observed between oxidative conversion and EOF results, but not with PFAS target analysis, suggesting that oxidative conversion may better represent the organofluorine burden in AFFF-impacted soils. Our findings indicate that TF analysis is unsuitable for tracing PFAS contamination in soils. Instead, combining oxidative conversion with routine PFAS target analysis is recommended to comprehensively assess PFAS contamination in soils.