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One of the major ways of delivering renewable energy generation from large-scale energy bases in northeast, northwest, and northern China, is to bundle the power from wind-photovoltaic-thermal units and then transmit it by alternating current/direct current (AC/DC) systems. The interactions among wind power units, photovoltaic (PV) power units, and high voltage direct current (HVDC) systems make the stability of the interconnected power system more complicated. In this paper, a framework model of wind-PV-thermal-bundled power transmitted by AC/DC systems is constructed based on the mathematical models of thermal power units, wind power units, PV power units, and HVDC transmission systems. Considering the fluctuations of wind power outputs and PV power outputs, a small-signal stability model of an interconnected power system with wind-PV-thermal-bundled power transmitted by AC/DC systems is established based on an existing stability theorem. The interactions among various forms of energy and their impacts on wind-PV-thermal-bundled power transmitted by AC/DC systems are studied through theoretical analysis and dynamic simulation. A sample interconnected power system is used to demonstrate the proposed method. It is shown by simulation results that the wind-PV-thermal-bundled power transmission distance; the electrical distance among wind power units, PV power units, and thermal power units; the grid-connected capacities of wind, PV, and thermal power units; and the power loading ratios of AC lines over DC lines all have various degrees of impacts on the stability of the interconnected power system. [ABSTRACT FROM AUTHOR]

Ammonia control has attracted attention due to the possibility for fine particles (PM 2.5) mitigation. Based on past decade ammonia emissions assessments and future predictions, this study seasonally evaluated the ammonia emissions reduction potential in 2025 and 2030 in Wuhan, a Central China megacity, according to the short-term and long-term predictable policies. Furthermore, combined with the reduction potential, PM 2.5 components observation and thermodynamic model, the effectiveness of implementing ammonia emission control to reduce PM 2.5 by 2025 and 2030 was explored seasonally. Results indicated that the total ammonia emissions are expected to decrease by 19.6–33.9% in 2025 and 2030 under positive reduction scenarios, or increase by 8.9–11.7% in the absence of any intervention. Livestock holds the largest potential for reducing ammonia emissions accounting for 46.4–52.5% of the total. Improvement of human excrement management in rural regions also contributes a 35–37% potential. Despite the implementation of exhaust requirements, ammonia emissions from vehicles in 2030 are expected to continue to increase by 55.3% and 23.5% under the regular (S1) and enhanced (S2) reduction strategy scenarios, respectively. Seasonally, the most potential source of ammonia reduction in spring, summer and fall remains livestock. While in winter, non-agricultural sources dominate the reduction potential. Further results indicated that by ammonia control is expected to decrease PM 2.5 concentration up to 5% (less than 1 μg m−3) in 2025–2030. Despite the better effectiveness in winter, ammonia control won't be an effective way to reduce PM 2.5 in Central China in future, from the management policies and areal ammonia-rich conditions. [Display omitted] • Wuhan's NH 3 emissions cut by 20–35% in 2025–2030 under active reduction scenario. • Livestock has the biggest reduction potential with 50% of the total in next decade. • The potential in nonwinter dominated by agriculture, but non-agriculture in winter. • PM 2.5 will decrease within 5% (<1 μg m−3) in 2025–2030 by ammonia control in Wuhan. [ABSTRACT FROM AUTHOR]

Ammonia control has received increasing attention as a measure to decrease particulate concentrations. Modeling analysis of observation data from central China over the period of September 2015 to August 2016 shows clear asymmetric responses of particulate pH and mass to ammonia emissions. With a change of ±80% of NHx (NH3 + NH4+), the corresponding ΔpH are +0.5 and −3.0, respectively, and the corresponding particulate NH4+ changes are +2.62% and −61.8%, respectively. This asymmetry implies that there is a Critical Total Ammonia Concentration, above which particulate pH and mass are insensitive to ammonia control. Analysis of the observation data suggests that the Critical Total Ammonia Concentration is −25%. The estimated cost for an NHx reduction of 25% is $140 – 320 million for Hubei province, which is the initial cost barrier before ammonia control can effectively affect particulate pH and mass in central China. This cost barrier will increase as NOx and SO2 emissions decrease. Key Points: Only after NHx reduction exceeds 25% can ammonia control effectively reduce the inorganic aerosol massMore NHx reduction will be required to reach the critical point of effective ammonia control as NOx and SO2 emissions decreaseA large enough NHx reduction (60%–80%) renders concurrent reduction of NOx emissions ineffective and even the effect of SO2 emission control is reduced [ABSTRACT FROM AUTHOR]

Residential coal combustion is one of the main sources of ambient polycyclic aromatic hydrocarbons (PAHs). Updating its emission estimation is limited by the shortages of emission factors, especially for them in different particle sizes and from different combustion conditions. PAH emission factors (EFs) for nine size-segregated particle segments emitted from smoldering and flaming combustion of residential coals (four kinds of raw coals (RCs) and three kinds of honeycomb coal briquettes (HCBs)) were obtained in China, using a dilution sampling system. EFs of PAHs for the flaming and smoldering of HCB ranged from 1.32 to 2.04 mg kg−1 and 0.35 to 5.36 mg kg−1, respectively. The EFs of PAHs for RC flaming combustion varied from 0.50 to 218.96 mg kg−1. About 53.5–96.4% and 47.4–90.9% of PAHs concentrated in PM2.1 and PM1.1, respectively. Different fuel types and combustion conditions strongly affected the PAH EFs. The PAH EF for the RC was 0.3 times that for HCB in Guizhou, which implied that PAH EFs for RC combustion were not always higher than those from HCB burning. For different combustion conditions, the PAH EFs from flaming were more than 2.5 times higher than those from smoldering for HCB except in the Anhui region. Results indicated that current PAH EFs may not be universal, which may bias the establishment of control policies for toxic pollutants emitted from domestic coal burning. On average, 73.2 ± 15.5% of total PAH potential toxicity risks were concentrated in submicron particles. More size-segregated PAH EFs for residential coal combustion should be investigated considering combustion conditions with a uniform sampling method in China. [ABSTRACT FROM AUTHOR]

Black carbon (BC), which is formed from the incomplete combustion of fuel sources (mainly fossil fuel, biofuel and open biomass burning), is a chemically inert optical absorber in the atmosphere. It has significant impacts on global climate, regional air quality and human health. During transportation, its physical and chemical characteristics as well as its sources change dramatically. To investigate the properties of BC (i.e., mass concentration, sources and optical properties) during intra-regional transport between the southern edge of the North China Plain (SE-NCP) and central China (CC), simultaneous BC observations were conducted in a megacity (Wuhan – WH) in CC, in three borderline cities (Xiangyang – XY, Suixian – SX and Hong'an – HA; from west to east) between the SE-NCP and CC, and in a city (Luohe – LH) in the SE-NCP during typical winter haze episodes. Using an Aethalometer, the highest equivalent BC (eBC) mass concentrations and the highest aerosol absorption coefficients (σabs) were found in LH in the SE-NCP, followed by the borderline cities (XY, SX and HA) and WH. The levels, sources, optical properties (i.e., σabs and absorption Ångström exponent, AAE) and geographic origins of eBC were different between clean and polluted periods. Compared with clean days, higher eBC levels (26.4 %–163 % higher) and σabs (18.2 %–236 % higher) were found during pollution episodes due to the increased combustion of fossil fuels (increased by 51.1 %–277 %), which was supported by the decreased AAE values (decreased by 7.40 %–12.7 %). The conditional bivariate probability function (CBPF) and concentration-weighted trajectory (CWT) results showed that the geographic origins of biomass burning (BC bb) and fossil fuel (BC ff) combustion-derived BC were different. Air parcels from the south dominated for border sites during clean days, with contributions of 46.0 %–58.2 %, whereas trajectories from the northeast showed higher contributions (37.5 %–51.2 %) during pollution episodes. At the SE-NCP site (LH), transboundary influences from the south (CC) exhibited a more frequent impact (with air parcels from this direction comprising 47.8 % of all parcels) on the ambient eBC levels during pollution episodes. At WH, eBC was mainly from the northeast transport route throughout the observation period. Two transportation cases showed that the mass concentrations of eBC, BC ff and σabs all increased, from upwind to downwind, whereas AAE decreased. This study highlights that intra-regional prevention and control for dominant sources at each specific site should be considered in order to improve the regional air quality. [ABSTRACT FROM AUTHOR]

Open biomass burning (OBB) has significant impacts on air pollution, climate change and potential human health. OBB has gathered wide attention but with little focus on the annual variation of pollutant emission. Central and eastern China (CEC) is one of the most polluted regions in China. This study aims to provide a state-of-theart estimation of the pollutant emissions from OBB in CEC from 2003 to 2015, by adopting the satellite observation dataset - the burned area product (MCD64Al) and the active fire product (MCD14 ML) - along with local biomass data (updated biomass loading data and high-resolution vegetation data) and local emission factors. The successful adoption of the double satellite dataset for long-term estimation of pollutants from OBB with a high spatial resolution can support the assessing of OBB on regional air quality, especially for harvest periods or dry seasons. It is also useful to evaluate the effects of annual OBB management policies in different regions. Here, monthly emissions of pollutants were estimated and allocated into a 1×1 km spatial grid for four types of OBB including grassland, shrubland, forest and cropland. From 2003 to 2015, the emissions from forest, shrubland and grassland fire burning had an annual fluctuation, whereas the emissions from crop straw burning steadily increased. The cumulative emissions of organic carbon (OC), elemental carbon (EC), methane (CH4), nitric oxide (NOx), non-methane volatile organic compounds (NMVOCs), sulfur dioxide (SO2), ammonia (NH3), carbon monoxide (CO), carbon dioxide (CO2) and fine particles (PM2:5) were 3:64×103, 2:87×102, 3:05×103, 1:82×103, 6:4×103, 2:12×102, 4:67×102, 4:59×104, 9:39×105 and 4:13×103 Gg in these years, respectively. Crop straw burning was the largest contributor for all pollutant emissions, by 84%-96%. For the forest, shrubland and grassland fire burning, forest fire burning emissions contributed the most, and emissions from grassland fire were negligible due to little grass coverage in this region. High pollutant emissions concentrated in the connection area of Shandong, Henan, Jiangsu and Anhui, with emission intensity higher than 100 tons per square kilometer, which was related to the frequent agricultural activities in these regions. Peak emission of pollutants occurred during summer and autumn harvest periods including May, June, September and October, during which ~ 50% of the total pollutant emissions were emitted in these months. This study highlights the importance of controlling the crop straw burning emissions. From December to March, the crop residue burning emissions decreased, while the emissions from forest, shrubland and grassland exhibited their highest values, leading to another small peak in emissions of pollutants. Obvious regional differences in seasonal variations of OBB were observed due to different local biomass types and environmental conditions. Rural population, agricultural output, economic levels, local burning habits, social customs and management policies were all influencing factors for OBB emissions. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to determine the optimal Foley catheter balloon volume (30-mL vs. 80-mL) and the maximum time for cervical ripening (12 hours vs. 24 hours) to improve vaginal delivery rate within 24 hours of induction. Methods: We conducted an open-label, randomized controlled trial in a teaching hospital in China. Women with a term singleton pregnancy, cephalic presentation, intact membrane and an unfavorable cervix (Bishop score <6) were randomly allocated, in 1:1:1:1 ratio, to receive either one of the four treatments: (1) 30-mL balloon for a maximum of 12 hours, (2) 30-mL balloon for a maximum of 24 hours, (3) 80-mL balloon for a maximum of 12 hours, and (4) 80-mL balloon for a maximum of 24 hours. The primary outcome was vaginal delivery within 24 hours. Secondary outcomes included cesarean section rate and maternal/neonatal morbidity. Data were analyzed on a per-protocol basis. Results: Five hundred and four women were recruited and randomized (126 women in each group); nine women did not receive the assigned intervention. More women achieved vaginal delivery within 24 hours in 12-hour Foley catheter groups than in the 24-hour Foley catheter groups (30-mL/12 hours: 54.5%, 30-mL/24 hours: 33.1%, 80-mL/12 hours: 46.4%, 80-mL/24 hours: 24.0%, p < 0.001). Cesarean section rates and the incidence of chorioaminonitis were comparable among four groups. After adjustment for confounding factors, both ripening time and balloon size did not affect the proportion of women delivered vaginally within 24 hours of induction. Conclusion: For women with an unfavorable cervix at term, induction of labor with a Foley catheter is safe and effective. Higher balloon volume (80-mL vs. 30-mL) and longer ripening time (24 hours vs. 12 hours) would not shorten induction to delivery interval or reduce cesarean section rate. Trial Registration: Chinese Clinical trial registry () [ABSTRACT FROM AUTHOR]

Background: The rates of preterm birth in Chinese women and the potential effects of differing environments are poorly understood. Aim: To determine the rate of preterm birth in Chinese women in China, Hong Kong and Western Australia. Methods: The rates of preterm birth were obtained from records of 26 611 pregnancies in Jiangsu Province in mainland China, 48 976 pregnancies in Hong Kong and 185 798 pregnancies in Western Australia. Results: Preterm birth rates increased from 2.6 and 2.9% in urban and rural Jiangsu Province, respectively, and 2.5% in China-born women in Western Australia who required an interpreter; to 4.9% in China-born women in Western Australia who did not require an interpreter; to 5.6% in non-resident Chinese women in Hong Kong; and 7.6% for women resident in Hong Kong. Within Western Australia, the rate of preterm birth was significantly less in women who were born in China and declared themselves to be Chinese (4.4%) than Caucasians (7.8%), other women who declared themselves to be 'Asian' (8.7%) and women of Aboriginal heritage (14.5%). Conclusions: The rate of preterm birth in China is relatively low but appears to differ in Chinese women in other environments. Differences between traditional Chinese and contemporary Western lifestyles, possibly including smoking and sexual practices, may contribute to the different rates of preterm birth. Further research in this area may provide avenues for the prevention of preterm birth and also help to prevent a possible rise in this complication of pregnancy as Chinese society continues on the path of economic and social reform. [ABSTRACT FROM AUTHOR]

• Heritage trees of the major cities in the Yangtze River basin region included 310 species. • Tangible and cultural values of heritage trees represented close connections between humans and nature. • Heritage tree species composition differed among geographical locations. The negative consequences of increased urbanization on native biological and cultural diversity have received considerable research attention. Biological and cultural diversity can be sustained by counteracting various processes of floristic homogenization and by reestablishing connections between humans and nature. However, effective instruments to help people reconnect with nature can be lacking, especially in cities. Green spaces provide cultural, aesthetic, and ecological services and can represent a critical component of native plant diversity in urban environments. We examined the species composition of heritage trees and the tangible and cultural values of these trees in 11 major cities in the Yangtze River basin of China. Our analysis explored the similarities of three arboreal types, namely heritage trees, urban greening components, and natural plant communities. Heritage tree species are diverse, containing 310 recorded species representing 159 genera and 64 families. Their tangible and cultural values are mainly medicinal (221 species), followed by timber (186), culture (134), traditional courtyard planting (131) and food (124). Notable geographical differences in heritage tree species composition identified in our analysis could be explained by cities adopting mostly species native to the locality or province. Heritage tree assemblages were similar in composition to undisturbed natural plant communities, and the two populations experienced comparable progressive decline with geographical distance. Urban greening components indicated negligible decline in similarity beyond the 1000 km threshold, indicating common sharing of exotic species across disparate locations. Heritage tree species associated with notable tangible and cultural values, superior genetic constitution, and adaptation to local growth conditions present suitable candidates for urban planting to improve tree performance and urban biodiversity. Their long history of association with local culture and rich cultural values can be enlisted to strengthen the connections of urban communities to nature and history, and to promote nature conservation within cities. Given increasing biological and biocultural homogenization, especially in urban areas, protecting heritage trees and using them in urban greening can slow this trend and enrich stocks of urban biodiversity. [ABSTRACT FROM AUTHOR]

Accelerated eutrophication in lakes reduces the number of submerged macrophytes and alters the residues of glyphosate and its degradation products. However, the effects of submerged macrophytes on the fate of glyphosate remain unclear. We investigated eight lakes with varying trophic levels along the middle and lower reaches of the Yangtze River in China, of which five lakes contained either glyphosate or aminomethylphosphate (AMPA). Glyphosate and AMPA residues were significantly positively correlated with the trophic levels of lakes (P < 0.01). In lakes, glyphosate is degraded through the AMPA and sarcosine pathways. Eight shared glyphosate-degrading enzymes and genes were observed in different lake sediments, corresponding to 44 degrading microorganisms. Glyphosate concentrations in sediments were significantly higher in lakes with lower abundances of soxA (sarcosine oxidase) and soxB (sarcosine oxidase) (P < 0.05). In the presence of submerged macrophytes, oxalic and malonic acids secreted by the roots of submerged macrophytes increased the abundance of glyphosate-degrading microorganisms containing soxA or soxB (P < 0.05). These results revealed that a decrease in the number of submerged macrophytes in eutrophic lakes may inhibit glyphosate degradation via the sarcosine pathway, leading to a decrease in glyphosate degradation and an increase in glyphosate residues. soxA and soxB promote glyphosate degradation via the sarcosine pathway. The abundances of soxA and soxB in sediments play a decisive role in determining the residual amount of glyphosate in lakes at different trophic levels. Submerged macrophytes increase the abundance of glyphosate-degrading microorganisms containing soxA or soxB. The results presented here indicate that the decline of submerged macrophytes is the primary cause of the increased glyphosate residues in eutrophic lakes. This study reveals the primary causes of increased glyphosate residues in eutrophic lakes and helps devise strategies for minimizing the accumulation of glyphosate in lakes. [Display omitted] • Residues of glyphosate + AMPA increased with lake eutrophication (P < 0.01). • Eight common glyphosate-degrading genes were detected in different lake sediments. • Glyphosate degradation was significantly affected by soxA and soxB (P < 0.05). • Plant root exudates could regulate microorganisms containing soxA and soxB. • Decline of submerged macrophytes leads to residual glyphosate in eutrophic lakes. [ABSTRACT FROM AUTHOR]

After releasing the Air Pollution Prevention Control and Action Plan (APPC) in China since 2013, the role of source emission control strategies and meteorological conditions on the reduction of air pollutants has received wide attention. Using an Aethalometer (AE31), equivalent black carbon (eBC) was monitored for 5.5-year after the APPC at Wuhan, a megacity in Central China, to identify its levels, sources, and variations trends. eBC varied in the range of 0.03–12.3 μg m−3, with the highest and lowest values in January (1.98 ± 1.70 μg m−3) and July (0.87 ± 0.61 μg m−3), respectively. The Kolmogorov-Zurbenk (KZ) filter and multiple-linear-regression were adopted to isolate the impacts of source emission control strategies and meteorological conditions on eBC variation. A long-term linear trend showed that emission-related reduction (7.79% yr−1) rather than meteorology-related reduction (4.51% yr−1) dominated the decreasing of eBC in the past years. Combining the KZ filter and Aethalometer model, the trends of eBC from fossil fuel combustion (eBC ff) and biomass burning (eBC bb) were calculated. eBC bb and eBC ff both showed decreasing trends with the reduction rates of 7.78% yr−1 and 7.76% yr−1, respectively. Backward trajectory analysis indicated that the air masses transported to the observational site from different regions in China all showed decreasing trend (1.64–18.7% yr−1) for eBC due to both the reduction from eBC bb (5.74–16.0% yr−1) and eBC ff (7.38–19.7% yr−1), suggesting the positive role of pollution control measures in migrating air pollution across China. • Human efforts dominate the reduction of black carbon. • Biomass burning and fossil fuel both contribute to the reduction of black carbon. • Black carbon reduction is joint efforts of local and regional prevention and control. [ABSTRACT FROM AUTHOR]

Objective: To analyze the initial effect following the relaxation of China's population control policy on the cesarean delivery (CD) rate using the 10-Group Classification System (TGCS).Methods: A retrospective study included all deliveries at a center in Nanjing, China, during 2014-2015. The deliveries were classified using the TGCS. The obstetric populations and the CD rates in each group were compared between 2014 and 2015.Results: Overall, 11 006 deliveries were analyzed. The overall CD rate increased from 28.3% (1623/5737) in 2014 to 33.8% (1782/5269) in 2015 (P<0.001). The largest contributor to the overall CD rate-accounting for approximately one-third of all CDs-were nulliparous women with a single cephalic term pregnancy and induced labor or prelabor CD (group 2); the CD rate in this group increased from 27.2% to 31.4%. Moreover, the proportion of women with a single cephalic term pregnancy with previous CD (group 5) steeply increased from 6.4% to 10.4% of all deliveries; the CD rate in this group during 2014-2015 was 76.6%.Conclusion: With China ending its one-child policy, the characteristics of the obstetric population changed. Women with a single cephalic term pregnancy with previous CD were the largest contributor to the CD rate increase. [ABSTRACT FROM AUTHOR]

Mitigation of ozone in urban agglomerations of developing countries remains challenging, due partly to inadequate knowledge of the relative importance of local sources versus transboundary transport, aggravated by lack of synchronous measurements of ozone and precursors. Here we investigate the spatial-temporal characteristics of ozone and its precursors measured synchronously at five cities of Wuhan City Cluster (WCC) in Central China during the high-ozone months of May–June 2018, facilitated by multiple models of different complexities. We find substantial cross-city diversities in the measured maximum daily averaged 8-h (MDA8) ozone, nitrogen oxides (NO x = NO + NO 2), volatile organic compounds (VOCs), VOCs/NO x ratios, and ozone formation potentials of VOCs, which are tied to distinctive local emission sources. GEOS-Chem simulations suggest that local anthropogenic emissions contribute 26.8–29.5% of ozone in each city averaged over May–June 2018, with higher values during ozone episodes (up to 32.0%). Transboundary transport from non-WCC Asian regions (18.5–19.2%) contributes much more than cross-city transport within WCC (2.5–3.1%) to ozone concentrations in the five cities. The contributions of background ozone from non-Asian anthropogenic emissions and global natural sources reach 48.9–51.6%. Thus local mitigation actions alone can substantially reduce city-level ozone; whereas the majority of ozone must be mitigated by country-wide or worldwide collaborations. Collaborations within an urban agglomeration alone may not effectively mitigate ozone. • Distinct city-level characteristics in ozone and precursors are found. • Substantial variabilities are found in photochemical formation of ozone across the cities and days. • Removing a city's local anthropogenic emissions alone can effectively mitigate ozone pollution. [ABSTRACT FROM AUTHOR]

• The reliable multi-year biomass burning emission variation was explored. • Emission factors for some ignored biomass types was proposed. • The moving of high emission for biomass burning from 2003 to 2014 was clear identified. Social-economic analysis was added to assess the high emission variation and analyze the policy implication quantitatively. Biomass burning (BB) has significant impacts on air quality, climate and human health. In China, the BB emission has changed substantially over the past decades while the multi-year variation held high uncertainty and the driving forces have addressed little attention. Here, this research aimed to conduct a comprehensive and systematic analysis of BB variation in China and provided precise and targeted BB emission reduction suggestions. The moving of high emission for BB from 2003 to 2014 was clearly identified, by the view of reliable emission estimation and anthropogenic impacts. Multiple satellite products, field survey, time varying biomass loading data and measured emission factors were adopted to better estimating BB emission and reducing the uncertainty. Social-economic analysis was added to assess the anthropogenic impacts on high emission variation quantitatively. Results showed that the cumulative BB emissions of OC, EC, CH 4 , NO X , NMVOC, SO 2 , NH 3 , CO, CO 2 , PM 2.5 and PM 10 during 2003-2014 were 1.6 × 104, 5.64 × 103, 3.57 × 104, 1.7 × 104, 5.44 × 104, 2.96 × 103, 6.77 × 103, 6.5 × 105, 1.15 × 107, 5.26 × 104 and 6.04 × 104 Gg, respectively. Crop straw burning (in-field and domestic) in northeast China plain (NEP), north China plain (NCP), northern arid and semiarid region and loess plateau were the key sources, averagely contributed 73% for all the pollutants emission. While domestic straw burning and firewood burning in Sichuan basin (SB), Yunnan-Guizhou plateau and southern China were main contributors, averagely accounting for 70% of all the pollutants emission. On regional level, high emissions were mainly found in SB, NCP and NEP. Temporally, high emissions were mainly found in crop sowing harvesting and heating seasons. From 2003 to 2014, the BB emission for different biomass species has changed significantly in different regions. High emission has gradually moved from SB to NCP and NEP. Firewood burning and domestic straw burning emission decreased by 47% and 14% in SB, respectively. In-field straw burning emission increased by 52% and 231% in NCP and NEP respectively and domestic straw burning emission increased by 62% in NEP. Emissions from heating season have decreased while emissions in corn harvest season were continuously increased. Analysis of Environmental kuznets curve, agricultural productivity level, human burning habits, rural energy structure and local control policies revealed the internal human driving strength of the variation for BB emission. The unbalanced development of social economy and the policy bias were primary drivers of limiting the BB management. BB emission will alleviate in NCP and aggravate in NEP. For the further emission reduction, effective measures for corn sources management, straw returning and rural energy utilization should be systematically considered. This research provides a clear evidence for the multi-year variation pattern of BB emissions, which is critical for pollution prediction, air quality modeling and targeted mitigation strategies for the key regions of China. [ABSTRACT FROM AUTHOR]

The contributions to aerosols and major chemical compositions (e.g. water-soluble ions-WSIs) from residential coal combustion (RCC) are still now existing large uncertainty in air quality modeling. The lake of reliable emission inventories for primary WSIs from RCC in China with measured emission factors (EFs) adopted is a major obstacle. With simulating burning test and dilution sampling method, this study detected the emission factors of nine size-segregated aerosols (0.43–10 μm) and associated WSIs emission factors from residential honeycomb briquettes and chunk coal burning, considering smoldering and flaming combustion status. Then a 1 km × 1 km grid cell-based emission inventory of RCC, including size-segregated particles and associated WSIs in China was established. The contributions of RCC to ambient fine particles were estimated by GEOS-Chem model. Results indicated that compared with anthracite coal combustion emission, bituminous coal burning emission can reduce the EFs of particles, while may increase the EFs of WSIs. The averaged EF of WSIs from honeycomb coal combustion was found 1.15 times higher than those for chunk coal burning. The total emission amounts of NH 4 +, Na+, K+, Mg2+, Ca2+, Cl−, NO 3 − and SO 4 2− in PM 2.1 from residential coal combustion in 2015 were 1915.3, 101.8, 1180.8, 50.1, 96.8, 4956.1, 552.4 and 7430.3 t, respectively, totally accounting for 2.03% of PM 2.1. SO 4 2− was the most important WSIs in fine particles released from RCC, occupied by 45.6% of the total WSIs. GEOS-Chem simulation indicated that RCC emission in China averagely accounted for 25.7% of ambient PM 2.5 and 7.1% for sulfate. Our results show that RCC emission is an important source for primary PM 2.5 and sulfate, suggesting the primary emission of WSI should be included in air quality modeling. More EFs monitoring of RCC of different types and regions in China should be conducted, for updating emission inventory and optimizing modeling results. Image 1 • Emission factors of water-soluble ions from domestic coal burning were obtained. • Honeycomb coal flaming and smoldering burning condition were considered. • Emission inventory for ions in PM 1.1 and PM 2.1 from domestic coal burning were established. • Contributions of PM 2.5 and ions from domestic coal burning were simulated by GEOS-Chem model. [ABSTRACT FROM AUTHOR]

Understanding of nitrous acid (HONO) production is crucial to photochemical studies, especially in polluted environments like eastern China. In-situ measurements of gaseous and particulate compositions were conducted at a rural coastal site during the 2018 spring Ozone Photochemistry and Export from China Experiment (OPECE). This data set was applied to investigate the recycling of reactive nitrogen through daytime heterogeneous HONO production. Although HONO levels increase during agricultural burning, analysis of the observation data does not indicate more efficient HONO production by agricultural burning aerosols than other anthropogenic aerosols. Box and 1-D modeling analyses reveal the intrinsic relationships between nitrogen dioxide (NO 2 ), particulate nitrate (pNO 3 ), and nitric acid (HNO 3 ), resulting in comparable agreement between observed and simulated HONO concentrations with any one of the three heterogeneous HONO production mechanisms, photosensitized NO 2 conversion on aerosols, photolysis of pNO 3 , and conversion from HNO 3 . This finding underscores the uncertainties in the mechanistic understanding and quantitative parametrizations of daytime heterogeneous HONO production pathways. Furthermore, the implications for reactive nitrogen recycling, ozone (O 3 ) production, and O 3 control strategies vary greatly depending on the HONO production mechanism. On a regional scale, the conversion of HONO from pNO 3 can drastically enhance O 3 production, while the conversion from NO 2 can reduce O 3 sensitivity to NOx changes in polluted eastern China.

Introduction: Preeclampsia is a disease with an unknown pathogenesis and is one of the leading causes of maternal and perinatal morbidity. At present, early identification of high-risk groups for preeclampsia and timely intervention with aspirin is an effective preventive method against preeclampsia. This study aims to develop a robust and effective preeclampsia prediction model with good performance by machine learning algorithms based on maternal characteristics, biophysical and biochemical markers at 11-13 +  6 weeks' gestation, providing an effective tool for early screening and prediction of preeclampsia., Methods: This study included 5116 singleton pregnant women who underwent PE screening and fetal aneuploidy from a prospective cohort longitudinal study in China. Maternal characteristics (such as maternal age, height, pre-pregnancy weight), past medical history, mean arterial pressure, uterine artery pulsatility index, pregnancy-associated plasma protein A, and placental growth factor were collected as the covariates for the preeclampsia prediction model. Five classification algorithms including Logistic Regression, Extra Trees Classifier, Voting Classifier, Gaussian Process Classifier and Stacking Classifier were applied for the prediction model development. Five-fold cross-validation with an 8:2 train-test split was applied for model validation., Results: We ultimately included 49 cases of preterm preeclampsia and 161 cases of term preeclampsia from the 4644 pregnant women data in the final analysis. Compared with other prediction algorithms, the AUC and detection rate at 10% FPR of the Voting Classifier algorithm showed better performance in the prediction of preterm preeclampsia (AUC=0.884, DR at 10%FPR=0.625) under all covariates included. However, its performance was similar to that of other model algorithms in all PE and term PE prediction. In the prediction of all preeclampsia, the contribution of PLGF was higher than PAPP-A (11.9% VS 8.7%), while the situation was opposite in the prediction of preterm preeclampsia (7.2% VS 16.5%). The performance for preeclampsia or preterm preeclampsia using machine learning algorithms was similar to that achieved by the fetal medicine foundation competing risk model under the same predictive factors (AUCs of 0.797 and 0.856 for PE and preterm PE, respectively)., Conclusions: Our models provide an accessible tool for large-scale population screening and prediction of preeclampsia, which helps reduce the disease burden and improve maternal and fetal outcomes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Xu, Wang, Wang, Tang, Duan, Zhao, Zheng and Hu.)

Ammonia control has attracted attention due to the possibility for fine particles (PM 2.5 ) mitigation. Based on past decade ammonia emissions assessments and future predictions, this study seasonally evaluated the ammonia emissions reduction potential in 2025 and 2030 in Wuhan, a Central China megacity, according to the short-term and long-term predictable policies. Furthermore, combined with the reduction potential, PM 2.5 components observation and thermodynamic model, the effectiveness of implementing ammonia emission control to reduce PM 2.5 by 2025 and 2030 was explored seasonally. Results indicated that the total ammonia emissions are expected to decrease by 19.6-33.9% in 2025 and 2030 under positive reduction scenarios, or increase by 8.9-11.7% in the absence of any intervention. Livestock holds the largest potential for reducing ammonia emissions accounting for 46.4-52.5% of the total. Improvement of human excrement management in rural regions also contributes a 35-37% potential. Despite the implementation of exhaust requirements, ammonia emissions from vehicles in 2030 are expected to continue to increase by 55.3% and 23.5% under the regular (S1) and enhanced (S2) reduction strategy scenarios, respectively. Seasonally, the most potential source of ammonia reduction in spring, summer and fall remains livestock. While in winter, non-agricultural sources dominate the reduction potential. Further results indicated that by ammonia control is expected to decrease PM 2.5 concentration up to 5% (less than 1 μg m -3 ) in 2025-2030. Despite the better effectiveness in winter, ammonia control won't be an effective way to reduce PM 2.5 in Central China in future, from the management policies and areal ammonia-rich conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Outdoor air pollution causes millions of premature deaths annually worldwide. Sulfate is a major component of particulate pollution. Winter sulfate observations in China show both high concentrations and an accumulation mode with a modal size >1 μm. However, we find that this observed size distribution cannot be simulated using classical gaseous and aqueous phase formation (CSF) or proposed aerosol-processing formation (APF) mechanisms. Specifically, the CSF simulation underestimates sulfate concentrations by 76% over megacities in China and predicts particle size distributions with a modal size of ∼0.35 μm, significantly smaller than observations. Although incorporating the APF mechanism in the atmospheric chemical model notably improves sulfate concentration simulation with reasonable parameters, the simulated sulfate particle size distribution remains similar to that using the CSF mechanism. We further conduct theoretical analyses and show that particles with diameters <0.3 μm grow rapidly (2-3 s) to 1 μm through the condensation of sulfuric acid in fresh high-temperature exhaust plumes, referred to as in-source formation (ISF). An ISF sulfate source equivalent to 15% of sulfur emissions from fossil fuel combustion largely explains both observed size distributions and mass concentrations of sulfate particles. The findings imply that ISF is a major source of wintertime micron-sized sulfate in China and underscore the importance of considering the size distribution of aerosols for accurately assessing the impacts of inorganic aerosols on radiative forcing and human health.

Objective: Congenital chylothorax (CC) is an uncommon congenital disease. The objective of this study was to analyze the clinical features, treatment, and outcome of infants with CC in a Chinese tertiary medical center., Methods: CC was defined as a non-traumatic pleural effusion with ≥ 80% lymphocytes detected before birth or within 28 days after birth. Clinical data were collected in CC infants discharged from June 2017 to March 2021., Results: A total of 24 CC infants were discharged during the study period, accounting for 67% of congenital pleural effusions. The median gestational age at birth was 36 +4  weeks (range 29 +5 -41 weeks) and the birth weight was 3025 g (range 1850-4250 g). Twenty-one infants were diagnosed antenatally. The median gestational age at the time of diagnosis was 30 +3  weeks (range 24-36 +6  weeks). Nine infants presented with hydrops fetalis; 18 were bilateral. Prenatal interventions were performed in 13 fetuses. Nine infants (38%) had birth asphyxia. Compared with the infants without hydrops fetalis, the infants with CC and hydrops fetalis had lower Apgar scores at 1 and 5 min (P < 0.05) and a lower gestational age at birth (P < 0.05). Postnatally, 17 infants required continuous pleural drainage for 10 days (range 2-30 days). Analysis of the pleural effusion showed a higher cell count, lymphocyte fraction, and protein content after enteral feeding (P < 0.05). Fifteen infants required mechanical ventilation; 9 did not require any respiratory support. Ten infants received a delayed feeding strategy and 17 received a medium-chain triglyceride (MCT) formula. Only 1 infant received octreotide therapy. Twenty-one infants survived and 3 died. The main cause of death was pulmonary dysplasia. The duration of hospital stay in survivors was 21.5 days (range 10-43) days. For infants with CC and hydrops fetalis, prenatal therapy shortened the duration of pleural drainage and the length of hospital stay (P < 0.05)., Conclusion: CC is the most common cause of congenital pleural effusions. The poor prognosis is mainly associated with prematurity, hydrops fetalis, and pulmonary dysplasia. Prenatal intervention may improve the outcome of infants with hydrops fetalis., (© 2022. The Author(s).)

Ammonia emission reduction is increasingly being considered one of the control measures to mitigate wintertime fine particulate matter (PM 2.5 ) pollution. Three wintertime observations from 2012 to 2018 in Wuhan, China, were analyzed to examine the effectiveness of ammonia control in wintertime PM 2.5 reduction based on the critical total ammonia concentration (CTAC, i.e., the inflection point of effective ammonia control for PM 2.5 mass reduction based on the asymmetric response of PM 2.5 to ammonia control). The CTAC gradually approached 0% (immediate effectiveness), with values of -26% in 2012, -23% in 2015, and -9% in 2018. At the observed ambient conditions, there were significant positive correlations of the CTAC with sulfate and total nitrate changes, in contrast to the negative correlation of the CTAC with total ammonia change. An approximately 10% total ammonia reduction could offset the decline in CTAC attributed to a 30-40% sulfate or 20-30% total nitrate reduction in Wuhan. This study indicates that the combined control of SO 2 + NO x (NO+NO 2 ) remains the preferred way to reduce inorganic particles in Central China at present, despite a tendency of the ambient chemical state moving towards effective ammonia control. However, as the CTAC approaches 0%, the effectiveness of ammonia and NO x reduction measures targeting wintertime PM 2.5 can greatly exceed that observed during the 2012-2018 period in Central China., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The International Symposium on Lipid Science and Health (ISLSH) has been organized annually by the Oil Crops Research Institute of Chinese Academy of Agricultural Sciences (OCRI-CAAS) since 2016. The purpose of the symposium was to bring together the leading lipid science and health researchers throughout the world to discuss the current state of knowledge as well as research needs with respect to chemistry and beneficial health properties of lipids. The Fifth International Symposium on Lipid Science and Health was held on October 2020 in Wuhan, Hubei, China. Speakers from China, the United States, Australia, Finland, and other countries delivered wonderful presentations. The presentations covered such diverse topics as lipid profiling and characterization, lipid preparation and modification, lipid improvement and regulation, and lipid nutrition and health. As a record of the symposium proceedings, this special issue comprises a selection of 27 papers from oral presentations and poster contributions and is prefaced by this introduction.

Introduction: In clinical practice, the ideal time at which to perform a Frozen-thawed Embryo Transfer (FET) after a failed In-vitro Fertilization-embryo Transfer (IVF-ET) is still unclear to most practicing physicians. In addition, physicians often delay the introduction of FET due to concerns on the possible residual effects of ovarian hyperstimulation, which may interfere with the regular menstrual cycle. Moreover, given that most of the published studies on the topic are retrospective with contradictory findings, it is crucial to provide evidence-based randomized control guides for clinical practice., Methods/analysis: The study is a randomized, non-inferiority, parallel-group, controlled trial that will enroll a total of 732 women undergoing their first FET after a failed fresh embryo transfer (ET) cycle. The participants will then be randomized into two groups based on a computer-generated randomized list. The two groups include: (i) an immediate group were FET will be carried out during the first menstrual cycle after a failed fresh ET cycle and (ii) a delayed group where FET will be carried out during the second menstrual cycle after a failed fresh ET cycle. Primary outcomes will be defined as viable pregnancies with fetal heartbeats, diagnosed through pelvic ultrasonography after twelve weeks of gestation., Ethics and Dissemination: The study was approved by the Ethics Committee of the Assisted Reproductive Medicine at the Affiliated Hospital of Shandong University of Traditional Chinese Medicine (SDTCM/E-2020.2.01). In addition, written informed consent will be obtained from all the participants before the study. The results of this trial will be disseminated in a peer-reviewed journal., Discussion: Currently, there is no consensus with regard to the duration after which the effects of ovarian stimulation are observed after a failed fresh ET and the optimal time required to begin FET. Moreover, no randomized controlled trial exists that compares the ongoing pregnancy rates after immediate versus delayed FET following a failed fresh ET cycle. Therefore, it is important to conduct a well-designed randomized trial to determine whether it is necessary to delay FET for at least one menstrual cycle after the failure of fresh ET., Clinical Trial Registration: ChiCTR2000033313 (http://www.chictr.org.cn/enIndex.aspx)., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Liu, Dong, Wang, Zheng, Song, Wang and Song.)

Objective: The aim of the present study was to investigate whether 25-hydroxyvitamin D (25(OH)D) status at 24-28 weeks is associated with blood lipids and pregnancy outcomes in patients with gestational diabetes mellitus (GDM)., Design: We performed an observational cohort study., Setting: The study was conducted in China., Participants: A total of 261 pregnant women diagnosed with GDM at 24-28 weeks of gestation in our hospital were included between June 2015 and December 2017. According to the levels of 25(OH)D, the women were divided into the G1 (<20 ng/mL) and G2 (≥20 ng/mL) groups. The levels of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), TG/HDL-c and TC/HDL-c ratios were obtained from medical records. Pregnancy outcomes included gestational weeks of birth and delivery mode. Newborn information included birth weight and body length. Differences between groups were tested with adjusted multiple linear regression., Results: The serum levels of 25(OH)D (14.1±3.4 ng/mL vs 28.5±6.5 ng/mL, p<0.001), TC (5.3±0.9 vs 5.6±0.8, p=0.006), HDL-c (1.8±0.4 vs 1.9±0.4, p=0.046) and LDL-c (2.5±0.6 vs 2.7±0.7, p=0.015) in the G2 group were significantly higher than those in G1 group, while TG/HDL-c ratios (1.43±0.7 vs 1.26±0.7, p=0.035) were significantly higher in the G1 group. Moreover, we failed to find a significant difference in pregnancy outcomes of mothers and newborns among the two groups (p>0.05). In models adjusting for maternal age, parity, height, blood pressure, socioeconomic status, educational attainment, pre-pregnancy body mass index, season and gestational age, maternal 25(OH)D was associated with TG/HDL-c ratios (B=-0.016; 95% CI= -0.025 to -0.006)., Conclusion: We found that there was no relationship between vitamin D and pregnancy/neonatal outcomes in our study. Maternal 25(OH)D at 24-28 weeks was inversely associated with TG/HDL-c ratios., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Petrochemical industry (PI) is an important emission sector of anthropogenic volatile organic compounds (VOCs). The health impacts of VOCs from PI have caused a wide attention by both scientists and publics. In this study, compositions, sources and health risks of VOCs at a typical petrochemical industrial park along the middle reach of Yangtze River were studied. The total VOC concentrations were in the range of 5.59 to 541 ppbv with a mean value of 54.8 ppbv. Alkanes (41.4 ± 15.7%) were the predominant group, followed by alkenes (19.9 ± 18.3%), OVOCs (14.7 ± 9.26%), halo hydrocarbon (11.2 ± 6.42%), aromatics (8.17 ± 5.08%), and acetylene (4.54 ± 2.80%). Compound-specific health risk results showed that acrolein and 1,3-butadiene had the highest non-carcinogenic risk (expressed by hazard ratio, HR: 22.8) and carcinogenic risk (expressed by lifetime cancer risk, LCR: 6.7 × 10 -3 ), respectively. Positive matrix factorization (PMF) model identified four VOC sources including fuel evaporation, industrial sources, ethylene industry and regional background with the average contributions of 35.6%, 12.0%, 26.5% and 25.9%, respectively. The receptor-originated approach combining the PMF model and conventional methods (HR and LCR) was used to assess the source-specific health risks. The non-cancer risks of four VOC sources were above safe level with regional background contributing most (38.3% or 4.91) to HR. The cancer risks of the four sources were below the tolerable level (<10 -4 ) and regional background also contributed most, with relative contribution of 58.4% (or 10 - ) to LCR. Our results are conductive to the formulation of countermeasures to reduce human exposure to ambient VOCs at petrochemical industrial parks in China.4.22 ) to LCR. Our results are conductive to the formulation of countermeasures to reduce human exposure to ambient VOCs at petrochemical industrial parks in China., (Copyright © 2019. Published by Elsevier B.V.)

Airborne fungi are a primary component of bioaerosols and proved to impact human health and climatic change. Deoxyribonucleic acid (DNA) is the essential component of most living organisms with relatively stable physicochemical properties. Little is known about day-night and pollution-episode differences of DNA mass ratio and fungal community in fine particles (PM 2.5 ) during serious winter haze events in China. Here we collected twenty-nine PM 2.5 samples every day and night during an entire winter haze evolution process in a megacity of Central China, Wuhan. DNA extraction and high-throughput sequencing methods were adopted to analyze fungal community. Results showed that mass ratio of DNA in PM 2.5 (R D/P %) changed with pollution process and showed significant negative correlations with PM 2.5 concentration (r = -0.72, P < 0.05) and temperature (r = -0.74, P < 0.05). R D/P became lower (4.40 × 10 -4 %) after haze episodes than before (7.16 × 10 -4 %). R D/P of night-samples (1.98 × 10 -4 -4.97 × 10 -4 %) were all lower than those for day-samples (3.05 × 10 -4 -9.99 × 10 -4 %) for the same period. The fungal species richness became much lower (76 operational taxonomic units (OTUs)) after haze episodes than before (198 OTUs). The species richness of night-samples (119-537 OTUs) were all higher than those of day-samples (71-198 OTUs) for the same period. The OTUs specially owned by night-samples were also more than those by day-samples. Fungal community diversity showed random variations. The fungal community composition of each sample was classified from phylum to genus level. Pathogenic fungi accounted for 8.60% of the entire fungal community. The significantly enriched fungal taxa in the night-sample group (29 taxa) were also much more than that in the day-sample group (9 taxa), which could explain the higher species richness of airborne fungi community in the night during the haze evolution episodes. These findings may serve as an important reference or inspiration to other aerosol studies focusing on human health and behavior of aerosols in the atmosphere., (Copyright © 2019 Elsevier B.V. All rights reserved.)