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Surface fine particulate matter (PM2.5) pollution can be enhanced by feedback processes induced by aerosol-radiation interactions (ARI) and aerosol-cloud interactions (ACI). Many previous studies have reported enhanced PM2.5 concentration induced by ARI and ACI for episodic events in China. However, few studies have examined the changes in the ARI- and ACI-induced PM2.5 enhancements over a long period, though the anthropogenic emissions have changed substantially in the last decade. In this study, we quantify the ARI- and ACI-induced PM2.5 changes for 2013–2021 under different meteorology and emission scenarios using the Weather Research and Forecasting model with Chemistry (WRF-Chem) and investigate the driving factors for the changes. Our results show that in January 2013, when China suffered from the worst PM2.5 pollution, the PM2.5 enhancement induced by ARI in eastern China (5.59 μg m−3) is larger than that induced by ACI (3.96 μg m−3). However, the ACI-induced PM2.5 enhancement shows a significantly smaller decrease ratio (51 %) than the ARI-induced enhancement (75 %) for 2013–2021, making ACI more important for enhancing PM2.5 concentrations in January 2021. Our analyses suggest that the anthropogenic emission reduction plays a key role in this shift. Owing to only anthropogenic emission reduction, the ACI-induced PM2.5 enhancement decreases by 43 % in January and 57 % in July, lower than the decrease ratio of the ARI-induced enhancement (57 % in January and 67 % in July). The primary reason for this phenomenon is that the decrease of ambient PM2.5 for 2013–2021 causes a disproportionately small decrease of liquid water path (LWP) and increase of cloud effective radius (Re) under the condition of high PM2.5 concentration, therefore the surface solar radiation attenuation (and hence boundary layer height reduction) caused by ACI decreases slower than that caused by ARI. Moreover, the lower decrease ratio of the ACI-induced PM2.5 enhancement is dominated by the lower decrease ratio of ACI-induced secondary PM2.5 component enhancement, which is additionally caused by smaller decrease ratio of the air temperature reduction and relative humidity (RH) increase. Our findings reveal that with the decrease of ambient PM2.5, the ACI-induced PM2.5 enhancement inevitably becomes more important, which needs to be considered in the formulation of control policies to meet the national PM2.5 air quality standard.

China is facing the challenge of synergistic reducing air pollutants and CO2 emissions in the coming decades. The coupled emission inventory of air pollutants and CO2 is a prerequisite to designing the synergetic emission reduction strategy. This study compiled China’s emission inventory of air pollutants and CO2 during 2005–2021 (ABaCAS-EI v2.0 dataset) based on a unified emission source framework and uniformed activity. The mitigation policies have decoupled the emissions of air pollutants and CO2 with economic development in China since 2013. In the context of growing activity levels, energy structure adjustment and energy & material saving brought a 7 % drop in the average annual growth rate of CO2 emissions after 2011; on the basis, end-of-pipe control contributed 51 %–98 % of air pollutants emission reductions after 2013. Sectors of industrial boilers and residential fossil combustion, and seven provinces (including Beijing, Tianjin, Shanghai, Jilin, Henan, Sichuan, and Qinghai) have achieved emission reductions of both air pollutants and CO2 during 2013–2021. The declining trends in both sectoral and regional emission ratios of air pollutants to CO2 indicated that the potential for synergistic emission reduction in China has declined from 2013 to 2021. The emission ratios in 2021 show that the residential fossil fuel combustion, iron and steel industry, and transportation have relatively higher co-benefits of SO2, PM2.5, NOx, and VOCs emission reductions when reducing CO2 emissions. Most of the cities with higher potential to synergistically reduce NOx, VOCs, and CO2 emissions are located within the Yangtze River Economic Belt; those with higher potential to co-control SO2 and CO2, and PM2.5 and CO2 are in southern and northeast China, respectively. What’s more, a further deconstruction of sectoral emissions in 2021 has suggested future reduction measures. For example, controlling coal consumption in the energy field; promoting innovative technologies with low air pollutant emission intensities and coal-saving effects in the iron and steel industry; combining coal and carbonate replacing technologies with separated particle control measures in the cement industry; controlling light-duty passenger vehicle, heavy-duty truck, agricultural machinery, and inland water transport in the transport field. Our dataset and analysis can provide insights into future co-control of air pollutants and CO2 emissions for China and other countries with the same demand worldwide. Our ABaCAS-EI v2.0 dataset can be accessed from https://doi.org/10.6084/m9.figshare.21777005.v1 (Li et al., 2022) by species, sector, and province.

The improved high-performance polymer cement mortar (PCM) and glass fiber reinforced plastic (GFRP) system reinforcement was used in the research to strengthen and repair the masonry structure, so as to improve its bond stress, anchoring force, and integral performance without changing the original structure and further study the shear performance of masonry structure strengthened by the combination of the two. The optimum ratio of improved high-performance PCM was determined by analyzing the bend-press ratio of PCM test block. Improved high-performance PCM and GFRP were combined to strengthen the damaged masonry wall, and a five-piece masonry wall composed of “improved high-performance PCM+ with or without GFRP+ different original wall failure modes before reinforcement” was designed. Through diagonal loading shear test, the shear strength, vertical displacement, horizontal relative displacement, and failure models of masonry walls were obtained, and the effects of five different reinforcement methods and different materials on shear strength, stiffness, ductility, and failure modes of masonry walls were studied. The results show that compared with the unreinforced original wall, the shear strength of the masonry wall reinforced with the improved O4PCM is 43.5% higher, and its stiffness is also greatly improved, but the failure mode is still brittle failure; the shear strength of masonry walls strengthened by O4PCM and GFRP is 6.5% higher than that of masonry walls strengthened by O4PCM alone, and the stiffness is also increased. Its failure mode changes from brittle failure to ductile failure; with a failure mode of ductile failure, the shear strength of masonry walls strengthened by P4PCM and GFRP and that strengthened by P6PCM and GFRP are 4.8% and 12.7% higher than that strengthened by O4PCM and GFRP, respectively, and the stiffness is also increased compared with that strengthened by O4PCM and GFRP. After experimental comparison, it is the best scheme to strengthen masonry wall with improved P6PCM and GFRP.

In this paper, the well-known shifted Grunwald–Letnikov formula is revisited to solve the two-dimensional fractional boundary value problems (FBVPs) with non-smooth solution. Both stability analysi...

Lipin 1 is an intracellular protein acting as a phosphatidic acid phosphohydrolase enzyme controlling lipid metabolism. Human recessive mutations in LPIN1 cause recurrent, early-onset myoglobinuria, a condition normally associated with muscle pain and weakness. Whether and how lipin 1 deficiency in humans leads to peripheral neuropathy is yet unclear. Herein, two novel compound heterozygous mutations in LPIN1 with neurological disorders, but no myoglobinuria were identified in an adult-onset syndromic myasthenia family. The present study sought to explore the pathogenic mechanism of LPIN1 in muscular and neural development. Methods: The clinical diagnosis of the proband was compared to the known 48 cases of LPIN1 recessive homozygous mutations. Whole-exome sequencing was carried out on the syndromic myasthenia family to identify the causative gene. The pathogenesis of lipin 1 deficiency during somitogenesis and neurogenesis was investigated using the zebrafish model. Whole-mount in situ hybridization, immunohistochemistry, birefringence analysis, touch-evoke escape response and locomotion assays were performed to observe in vivo the changes in muscles and neurons. The conservatism of the molecular pathways regulated by lipin 1 was evaluated in human primary glioblastoma and mouse myoblast cells by siRNA knockdown, drug treatment, qRT-PCR and Western blotting analysis. Results: The patient exhibited adult-onset myasthenia accompanied by muscle fiber atrophy and nerve demyelination without myoglobinuria. Two novel heterozygous mutations, c.2047A>C (p.I683L) and c.2201G>A (p.R734Q) in LPIN1, were identified in the family and predicted to alter the tertiary structure of LPIN1 protein. Lipin 1 deficiency in zebrafish embryos generated by lpin1 morpholino knockdown or human LPIN1 mutant mRNA injections reproduced the myotomes defects, a reduction both in primary motor neurons and secondary motor neurons projections, morphological changes of post-synaptic clusters of acetylcholine receptors, and myelination defects, which led to reduced touch-evoked response and abnormalities of swimming behaviors. Loss of lipin 1 function in zebrafish and mammalian cells also exhibited altered expression levels of muscle and neuron markers, as well as abnormally enhanced Notch signaling, which was partially rescued by the specific Notch pathway inhibitor DAPT. Conclusions: These findings pointed out that the compound heterozygous mutations in human LPIN1 caused adult-onset syndromic myasthenia with peripheral neuropathy. Moreover, zebrafish could be used to model the neuromuscular phenotypes due to the lipin 1 deficiency, where a novel pathological role of over-activated Notch signaling was discovered and further confirmed in mammalian cell lines.

In this paper, an efficient algorithm is presented by adopting the extrapolation technique to improve the accuracy of finite difference schemes for two-dimensional space-fractional diffusion equations with non-smooth solution. The popular fractional centered difference scheme is revisited and the stability and error estimation of numerical solution are given in maximum norm. Based on the analysis of leading singularity of exact solution for the underlying problem, the extrapolation technique and numerical correction method are exploited to enhance the accuracy and convergence rate of the computation. Two numerical examples are provided to validate the theoretical prediction and efficiency of the algorithm. It is shown that, by using the proposed algorithm, both accuracy and convergence rate of numerical solutions can be significantly improved and the second-order accuracy can even be recovered for the equations with large fractional orders.

Interest in the development of grid-level energy storage systems has increased over the years. As one of the most popular energy storage technologies currently available, batteries offer a number of high-value opportunities due to their rapid responses, flexible installation, and excellent performances. However, because of the complexity, multifunctionality, and wide deployment of power grids, trade-offs in battery performance exist, especially when considering economics, environmental effects, and safety. Therefore, establishing a comprehensive assessment of battery technologies is an urgent undertaking. In this work, we present an analysis of rough sets to evaluate the integration of battery systems (e.g., lead–acid batteries, lithium-ion batteries, nickel/metal–hydrogen batteries, zinc–air batteries, and Na–S batteries) into a power grid. Specifically, technological properties, economic significance, environmental effects, and safety of these battery systems are evaluated on the basis of rough set theory. In addition, some perspectives are provided to promote the development of battery technologies for grid-level energy storage.

In this paper, we mainly investigate the fractional spectral collocation discretization of optimal control problem governed by a space-fractional diffusion equation. Existence and uniqueness of the solution to optimal control problem is proved. The continuous first order optimality condition is derived. The eigenfunctions of two classes of fractional Strum–Liouville problems are used as basis functions to approximate state variable and adjoint state variable, respectively. The fractional spectral collocation scheme for the control problem is constructed based on ‘first optimize, then discretize’ approach. Note that the solutions of fractional differential equations are usually singular near the boundary, a generalized fractional spectral collocation scheme for the control problem is proposed based on ‘first optimize, then discretize’ approach. A projected gradient algorithm is designed based on the discrete optimality condition. Numerical experiments are carried out to verify the effectiveness of the proposed numerical schemes and algorithm.

Civil aircraft emissions during landing and takeoff (LTO) are important air pollutant sources, but have been given insufficient attention in China. Accurate estimation of these emissions is limited by a lack of important parameters, such as detailed flight information and the dynamic time in climb and approach modes during LTO that are dependent on mixing layer height (MLH). We developed a flight-time/flight-height relationship using real-time height information in Aircraft Meteorological Data Relay data, and then calculated the actual time for each flight in those two modes based on the actual MLH from meteorological observation. Hourly emissions of civil aircraft were then estimated based on the database of each flight. Total emissions of NOx, CO, SO2, HC and PM from LTO cycles of domestic flights in China during 2015 were 37.78 Gg, 30.25 Gg, 12.00 Gg, 2.38 Gg and 0.75 Gg, respectively. Substantial monthly, daily and hourly variations of emissions due to the flight schedule as well as MLH were calculated. Large differences were found between the new estimation and emissions calculated based on traditional method. Compared with the emissions estimated based on default parameter obtained from International Civil Aviation Organization, the average difference of annual emission among airports with new estimation for various pollutants was approximately 30.3% in climb mode and 81.4% in approach mode; compared with the emissions estimated based on the method proposed by China National Guide, the average difference of annual emission among airports were 37.4% (NOx), 8.4% (CO), 73.1% (HC) and 58.1% (PM) during LTO process. The monthly airport-specific emissions per LTO were also proposed. These can provide necessary and meaningful support for the revision of the values in National Guide.

As one of the most malicious cancers, pancreatic cancer is difficult to treat due to the lack of effective early diagnosis. Therefore, it is urgent to find reliable diagnostic and predictive markers for the early detection of pancreatic cancer. In recent years, the detection of circulating cell-free DNA (cfDNA) methylation in plasma has attracted global attention for non-invasive and early cancer diagnosis. Here, we carried out a genome-wide cfDNA methylation profiling study of pancreatic ductal adenocarcinoma (PDAC) patients by methylated DNA immunoprecipitation coupled with high-throughput sequencing (MeDIP-seq). Compared with healthy individuals, 775 differentially methylated regions (DMRs) located in promoter regions were identified in PDAC patients with 761 hypermethylated and 14 hypomethylated regions; meanwhile, 761 DMRs in CpG islands (CGIs) were identified in PDAC patients with 734 hypermethylated and 27 hypomethylated regions (p-value < 0.0001). Then, 143 hypermethylated DMRs were further selected which were located in promoter regions and completely overlapped with CGIs. After performing the least absolute shrinkage and selection operator (LASSO) method, a total of eight markers were found to fairly distinguish PDAC patients from healthy individuals, includingTRIM73,FAM150A,EPB41L3,SIX3,MIR663,MAPT,LOC100128977, andLOC100130148. In conclusion, this work identified a set of eight differentially methylated markers that may be potentially applied in non-invasive diagnosis of pancreatic cancer.

Intermediate crack (IC) debonding failure is one of the common bending failure forms of fiber-reinforced polymer (FRP)-strengthened reinforced concrete (RC) beams. In this paper, a new prediction model for IC debonding in FRP-strengthened RC beams is proposed based on fracture mechanics and cohesive zone model (CZM), which takes into account the coupling effect of many parameters and has the advantages of high precision and simple expression. The nonlinear behavior of FRP-strengthened RC beams and the influence of flexural cracks are reasonably considered in this model, whereas all existing analytical models based on the CZM neglect this effects. To verify the accuracy of this model, we established a database containing 248 test data from the existing literature. By comparing the differences between the predicted and experimental results, we analyzed the causes of the error and established a semiempirical model. To test the reliability of the model, it is evaluated using the database constructed in this paper together with four representative strength models. The results show that the semiempirical model has a high accuracy.

Rural residential coal combustion (RRCC) has detrimental effects on air quality, climate, and human health. There are large uncertainties regarding emissions from RRCC owing to the lack of consideration of several key factors (e.g. combination modes of coal and stoves, combustion modes, and high temporal resolution). In this study, we provided a new estimation framework for RRCC emissions through a case study in the Beijing-Tianjin-Hebei (BTH) region, China. The emission estimations were improved according to four aspects, namely (1) coal-specific and stove-specific coal consumption was calculated based on face-to-face field interviews of 6700 valid volunteers/households covering 288 villages in 50 counties; (2) the influences of combustion modes (flaming and smoldering modes) on emissions were considered; (3) emissions of different fuel-stove combinations were estimated based on coal, stove, and combustion mode-specific RRCC consumption and localised emission factors; and (4) a method for emission estimation with high temporal resolution (1 h) was developed. The results indicated that RRCC emitted 413.6 kt SO2, 55.7 kt NOx, 5717.3 kt CO, 149.4 kt VOCs, 167.1 kt PM2.5, 18.2 kt EC, 32.5 kt OC, and 8.2 kt NH3 in 2016. The combination of bituminous coal and an advanced coal stove was the most significant contributor (20.7–71.8%) to various pollutant emissions. Coal combusted under the flaming mode contributed to most (81.9%) of the total coal consumption, and thus emitted the majority (50.8–99.8%) of pollutants, except for VOCs. Meanwhile, that under the smoldering mode only accounted for 18.1% of the total consumption, but contributed 49.2% and 74.7% of the CO and VOCs emissions, respectively. Two clear emission peaks occurred at approximately 7:00–9:00 and 18:00–20:00. The detailed coal consumption and emissions with high temporal and spatial resolution can provide sound data for further research on rural environmental issues and scientific support to pollution control strategies.

Beijing, the capital of China, suffers from severe atmospheric aerosol pollution; nevertheless, a comprehensive study of the constituents and sources of PM1 is still lacking, and the differences between PM1 and PM2.5 are still unclear. In this study, an intensive observation was conducted to reveal the pollution characteristics of PM1 and PM2.5 in Beijing in autumn. Positive matrix factorization (PMF), backward trajectories and a potential source contribution function (PSCF) model were used to identify the source categories and source areas of PM1 and PM2.5. The results showed that the average concentrations of PM1 and PM2.5 reached 78.20μg/m3 and 95.47μg/m3 during the study period, respectively. PM1 contributed greatly to PM2.5. The PM1/PM2.5 value increased from 73.6% to 90.1% with PM1 concentration growing from 150μg/m3. Higher secondary inorganic aerosol (SIA) proportions (31.3%-70.8%) were found in PM1. The higher fraction of SIA, OC, EC and typical elements in PM1 illustrated that anthropogenic components accumulated more in smaller size particles. Three typical weather patterns causing the heavy pollution in autumn were found as follows: (1) Siberian high and uniform high pressure field, (2) cold front and low-voltage system, and (3) uniform low pressure field. A PMF analysis indicated that secondary aerosols and coal combustion, vehicle, industry, biomass burning, and dust were the important sources of PM, accounting for 53.8%, 8.0%, 13.0%, 13.2% and 12.0% of PM1, respectively, and for 47.5%, 9.9%, 12.4%, 8.4% and 21.8% of PM2.5, respectively. The HYSPLIT and chemical components analysis indicated the potential contribution from biomass burning and fertilization ammonia emissions to PM1 in autumn. The source areas were similar for PM1 and PM1-2.5 under general polluted conditions, but during the heavily polluted periods, the source areas were distributed in farther regions from Beijing for PM1 than for PM1-2.5.

This paper presents a numerical scheme for optimal control problem governed by a time-fractional diffusion equation based on a Legendre pseudo-spectral method for space discretization and a finite ...

Motor vehicles are recognised as important contributors to urban air pollution. However, few studies have focused on their contribution from the point of view of regional transport. To address this gap, the validated WRF-CAMx-PSAT modelling system was applied to quantitatively evaluate the impact of vehicular emissions on air pollution in the Beijing-Tianjin-Hebei (BTH) region of China in 2014. We found that although motor vehicle is a near-surface source, it can significantly influence the air quality through regional transmission, especially with respect to atmospheric PM2.5 and NO3− during haze days. The fraction of non-local emissions to the overall vehicular emission contribution was 45.2% and 60.3% for PM2.5 and NO3−, respectively. Furthermore, the regional transport of vehicular emissions played an increased significant role in contributing toward air pollution on haze days. The contribution of non-local vehicular emissions to atmospheric PM2.5 and NO3− from non-haze to haze days increased by 38% and 27%, respectively. An 8.01 times change in the per unit (104 ton) vehicular emission contribution (PVEC) of non-local emissions from non-haze to haze days for NO3− indicated that the control of non-local vehicular emissions can be more effective for the mitigation of NO3− pollution, as compared to the mitigation of undifferentiated emissions from different sources. An obvious power function relationship was found between the PVEC and transport distance. Attenuation index was defined to analyse the degree of attenuation of pollutants with distance. An obvious decrease in the attenuation coefficient from non-haze to haze days for NO3− indicated that the regional transport of NO3− was more prominent on haze days from vehicular emission. Thus, this study can provide new knowledge for understanding the environmental impact of vehicular emissions. In addition, the results can provide a scientific basis for formulating effective regional coordination control strategies for air pollution.

Ammonia (NH3) emitted from motor vehicles is a by-product of measures taken to reduce emissions of other pollutants (e.g. NOx and CO) and has potentially important environmental impacts. NH3 levels can be impacted by various emission standards. However, there is a lack of investigations of the influences from the implementation of different vehicular emission standards on long-term changes in NH3 emissions. To fill this gap, we estimated the inter-annual NH3 emissions of light-duty gasoline vehicles (LDGVs) under different emission standards (State 0 to State V) from 1999 to 2017 and investigated the emission change characteristics under the rapidly developing Chinese economy. Results showed that the NH3 emissions from LDGVs had a sharp, 42-fold increase (from 1.8 Gg to 77.9 Gg). However, NH3 emissions per capita have begun to decrease with increases in socioeconomic development, presenting an inverted U-shaped tendency as a function of per capita GDP. Further exploration indicated that the decline in emission factors, as determined by upgrades in emission standards, was the decisive factor in promoting the downward trend in per capita emissions. This suggests that continuously upgrading emission standards has offset the increase in NH3 emissions due to the rapid growth of motor vehicles. Quantitative scenario analysis showed a two-stage impact of emission standards on NH3 emissions: emissions would decrease 77% (48%–90% for different years) if State I and State II were not implemented; while if none of standards were upgraded (State III to State V), NH3 emissions would increase 118% (13%–224% for different years), 2–6 times the impacts from the growth of vehicle population and the decline of vehicle kilometres traveled. The data and findings in this study can provide scientific support for understanding air pollution in urban areas and for formulating further vehicle pollution mitigation measures in China and other countries.

Beijing, the capital of China, suffers from severe atmospheric aerosol pollution; nevertheless, a comprehensive study of the constituents and sources of PM

Multi-year (1999–2014) vehicular unregulated pollutants emissions in China, including SO 2 , CH 4 , N 2 O, NH 3 , Indeno(1,2,3- cd )pyrene (IPY), Benzo( k )fluoranthene (BkF), Benzo( b )fluoranthene (BbF), Benzo( a )pyrene (BaP), dioxins and furans, were estimated based on emission factors calculated by COPERT. The inter-annual trends, correlation with GDP and population, spatial distribution characteristics, contributions from various vehicle types for the ten pollutants emissions were analyzed. Results showed that the emissions of the above ten pollutants changed from approximately 576.9 Gg, 130.0 Gg, 8.1 Gg, 2.1 Gg, 1.0 Mg, 1.1 Mg, 1.4 Mg, 0.5 Mg, 7.4 g and 15.6 g in 1999 to 193.8 Gg, 171.1 Gg, 79.1 Gg, 117.8 Gg, 3.5 Mg, 6.7 Mg, 6.8 Mg, 2.9 Mg, 37.6 g and 79.1 g in 2014, respectively. Implementation of stringent sulfur content limit during the past decade reduced approximately 94.4% of the SO 2 emission in 2014. CH 4 and N 2 O increased from 1999 to 2011, but began to decrease since 2012; NH 3 emission had the highest annual average change rate (35.5%) from 1999 to 2014; PAHs, dioxins and furans increased continuously during the past decade. The vehicular emissions were higher in Guangdong, Shandong, Henan, Jiangsu, Zhejiang and Hebei. Good linear correlation between vehicular emissions and GDP was found (except SO 2 ); in the provinces/municipalities with higher population density, the emission density was also larger, indicating more significant vehicular emissions' potential damage on human health. HDT and PC, PC and MC, PC and BUS were the major contributors to SO 2 , CH 4 , N 2 O emissions, respectively. In 2014, PC was the dominant contributor to NH 3 emission; PC, BUS and HDT had higher fraction in the total IPY and BaP emissions; HDT was the major contributor to BkF and BbF emissions. In addition, the uncertainties of estimated emissions were also analyzed based on Monte Carlo simulation.