Unveiling the health impacts of air pollution transport in China.

The transport of atmospheric pollutants plays a pivotal role in regional air pollution, highlighting critical concerns over the unequal health outcomes that arise from such transport. While previous researches predominantly focused on key areas in the battle against air pollution, the intensification of control measures necessitates a national perspective to comprehend the health impacts due to pollution transport. Our study establishes an integrated assessment framework that combine an emission-concentration response surface model with a health impact evaluation model to analyse the nationwide health impacts of PM2.5 and O3 pollution transport across China's 31 provinces. We found that, interprovincial transport of PM2.5 and O3 contributed to 747,000 and 110,000 deaths respectively in 2017, which amounts to 38% and 48% of deaths caused by total anthropogenic emissions. North, East, and Central China together contribute 82% and 69% to the health impacts caused by regional PM2.5 and O3 transport respectively, and the transport among these three regions is also significant. The analysis of interprovincial health impact transport shows that, for PM2.5, the top contributors are Hebei, Shandong, Henan, Anhui, and Jiangsu, with the most affected being Henan, Shandong, Jiangsu, Hebei, and Guangdong. Regarding O3, Shandong, Hebei, Henan, Jiangsu, and Anhui contribute the most, while Henan, Shandong, Hebei, Jiangsu, and Anhui are the most affected. This study can shed lights on regional control strategies by prioritizing control areas based on the health impact of air pollution transport in China.

Integrated Benefits of Synergistically Reducing Air Pollutants and Carbon Dioxide in China.

China's advancements in addressing air pollution and reducing CO2 emissions offer valuable lessons for collaborative strategies to achieve diverse environmental objectives. Previous studies have assessed the mutual benefits of climate policies and air pollution control measures on one another, lacking an integrated assessment of the benefits of synergistic control attributed to refined measures. Here, we comprehensively used coupled emission inventory and response models to evaluate the integrated benefits and synergy degrees of various measures in reducing air pollutants and CO2 in China during 2013-2021. Results indicated that the implemented measures yielded integrated benefits value at 6.7 (2.4-12.6) trillion Chinese Yuan. The top five contributors, accounting for 55%, included promoting non-thermal power, implementing end-of-pipe control technologies in power plants and iron and steel industry, replacing residential scattered coal, and saving building energy. Measures demonstrating high synergies and integrated benefits per unit of reduction (e.g., green traffic promotion) yielded low benefits mainly due to their low application, which are expected to gain greater implementation and prioritization in the future. Our findings provide insights into the effectiveness and limitations of strategies aimed at joint control. By ranking these measures based on their benefits and synergy, we offer valuable guidance for policy development in China and other nations with similar needs.

Air Quality, Health, and Equity Benefits of Carbon Neutrality and Clean Air Pathways in China.

In the pursuit of carbon neutrality, China's 2060 targets have been largely anchored in reducing greenhouse gas emissions, with less emphasis on the consequential benefits for air quality and public health. This study pivots to this critical nexus, exploring how China's carbon neutrality aligns with the World Health Organization's air quality guidelines (WHO AQG) regarding fine particulate matter (PM2.5) exposure. Coupling a technology-rich integrated assessment model, an emission-concentration response surface model, and exposure and health assessment, we find that decarbonization reduces sulfur dioxide (SO2), nitrogen oxides (NOx), and PM2.5 emissions by more than 90%; reduces nonmethane volatile organic compounds (NMVOCs) by more than 50%; and simultaneously reduces the disparities across regions. Critically, our analysis reveals that further targeted reductions in air pollutants, notably NH3 and non-energy-related NMVOCs, could bring most Chinese cities into attainment of WHO AQG for PM2.5 5 to 10 years earlier than the pathway focused solely on carbon neutrality. Thus, the integration of air pollution control measures into carbon neutrality strategies will present a significant opportunity for China to attain health and environmental equality.

Health-Oriented Emission Control Strategy of Energy Utilization and Its Co-CO2 Benefits: A Case Study of the Yangtze River Delta, China.

Reducing air pollutants and CO2 emissions from energy utilization is crucial for achieving the dual objectives of clean air and carbon neutrality in China. Thus, an optimized health-oriented strategy is urgently needed. Herein, by coupling a CO2 and air pollutants emission inventory with response surface models for PM2.5-associated mortality, we shed light on the effectiveness of protecting human health and co-CO2 benefit from reducing fuel-related emissions and generate a health-oriented strategy for the Yangtze River Delta (YRD). Results reveal that oil consumption is the primary contributor to fuel-related PM2.5 pollution and premature deaths in the YRD. Significantly, curtailing fuel consumption in transportation is the most effective measure to alleviate the fuel-related PM2.5 health impact, which also has the greatest cobenefits for CO2 emission reduction on a regional scale. Reducing fuel consumption will achieve substantial health improvements especially in eastern YRD, with nonroad vehicle emission reductions being particularly impactful for health protection, while on-road vehicles present the greatest potential for CO2 reductions. Scenario analysis confirms the importance of mitigating oil consumption in the transportation sector in addressing PM2.5 pollution and climate change.

Spatially and Temporally Differentiated NOx and VOCs Emission Abatement Could Effectively Gain O3-Related Health Benefits.

The increasing level of O3 pollution in China significantly exacerbates the long-term O3 health damage, and an optimized health-oriented strategy for NOx and VOCs emission abatement is needed. Here, we developed an integrated evaluation and optimization system for the O3 control strategy by merging a response surface model for the O3-related mortality and an optimization module. Applying this system to the Yangtze River Delta (YRD), we evaluated driving factors for mortality changes from 2013 to 2017, quantified spatial and temporal O3-related mortality responses to precursor emission abatement, and optimized a health-oriented control strategy. Results indicate that insufficient NOx emission abatement combined with deficient VOCs control from 2013 to 2017 aggravated O3-related mortality, particularly during spring and autumn. Northern YRD should promote VOCs control due to higher VOC-limited characteristics, whereas fastening NOx emission abatement is more favorable in southern YRD. Moreover, promotion of NOx mitigation in late spring and summer and facilitating VOCs control in spring and autumn could further reduce O3-related mortality by nearly 10% compared to the control strategy without seasonal differences. These findings highlight that a spatially and temporally differentiated NOx and VOCs emission control strategy could gain more O3-related health benefits, offering valuable insights to regions with severe ozone pollution all over the world.

Emerging role and mechanism of HACE1 in the pathogenesis of neurodegenerative diseases: A promising target.

HACE1 is a member of the HECT domain-containing E3 ligases with 909 amino acid residues, containing N-terminal ankyrin-repeats (ANK) and C-terminal HECT domain. Previously, it was shown that HACE1 is inactive in human tumors and plays a crucial role in the initiation, progression, and invasion of malignant tumors. Recent studies indicated that HACE1 might be closely involved in neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and Huntington's disease. HACE1 interacts with its substrates, including Ras-related C3 botulinum toxin substrate 1 (Rac1), nuclear factor erythroid 2-related factor 2 (Nrf2), tumor necrosis factor receptor (TNFR), and optineurin (OPTN), through which participates in several pathophysiological processes, such as oxidative stress, autophagy and inflammation. Therefore, in this review, we elaborately describe the essential substrates of HACE1 and illuminate the pathophysiological processes by which HACE1 is involved in neurodegenerative diseases. We provide a new molecular target for neurodegenerative diseases.

Unpacking the factors contributing to changes in PM2.5-associated mortality in China from 2013 to 2019.

From 2013 to 2019, a series of air pollution control actions significantly reduced PM2.5 pollution in China. Control actions included changes in activity levels, structural adjustment (SA) policy, energy and material saving (EMS) policy, and end-of-pipe (EOP) control in several sources, which have not been systematically studied in previous studies. Here, we integrate an emission inventory, a chemical transport model, a health impact assessment model, and a scenario analysis to quantify the contribution of each control action across a range of major emission sources to the changes in PM2.5 concentrations and associated mortality in China from 2013 to 2019. Assuming equal toxicity of PM2.5 from all the sources, we estimate that PM2.5-related mortality decreased from 2.52 (95 % confidence interval, 2.13-2.88) to 1.94 (1.62-2.24) million deaths. Anthropogenic emission reductions and declining baseline incidence rates significantly contributed to health benefits, but population aging partially offset their impact. Among the major sources, controls on power plants and industrial boilers were responsible for the highest reduction in PM2.5-related mortality (∼80 %), followed by industrial processes (∼40 %), residential combustion (∼40 %), and transportation (∼30 %). However, considering the potentially higher relative risks of power plant PM2.5, the adverse effects avoided by their control could be ∼2.4 times the current estimation. Our power plant sensitivity analyses indicate that future estimates of source-specific PM2.5 health effects should incorporate variations in individual source PM2.5 effect coefficients when available. As for the control actions, while activity levels increased for most sources, SA policy significantly reduced the emissions in residential combustion and industrial boilers, and EOP control dominated the contribution in health benefits in most sources except residential combustion. Considering the emission reduction potential by source and control actions in 2019, our results suggest that promoting clean energy in residential combustion and enforcing more stringent EOP control in the iron and steel industry should be prioritized in the future.

The development of local ambient air quality standards: A case study of Hainan Province, China.

The ambient air quality standard (AAQS) is a vital policy instrument for protecting the environment and human health. Hainan Province is at the forefront of China's efforts to protect its ecological environment, with an official goal to achieve world-leading air quality by 2035. However, neither the national AAQS nor the World Health Organization guideline offers sufficient guidance for improving air quality in Hainan because Hainan has well met the former while the latter is excessively stringent. Consequently, the establishment of Hainan's local AAQS becomes imperative. Nonetheless, research regarding the development of local AAQS is scarce, especially in comparatively more polluted countries such as China. The relatively high background values and significant interannual fluctuations in air pollutant concentrations in Hainan present challenges in the development of local AAQS. Our research proposes a world-class local AAQS of Hainan Province by reviewing the AAQS in major countries or regions worldwide, analyzing the influence of different statistical forms, and carefully evaluating the attainability of the standard. In the proposed AAQS, the annual mean concentration limit for PM2.5, the annual 95th percentile of daily maximum 8-h mean (MDA8) concentration limit for O3, and the peak season concentration limit for O3 are set at 10, 120, and 85 µg/m3, respectively. Our study indicates that, with effective control policies, Hainan is projected to achieve compliance with the new standard by 2035. The implementation of the local AAQS is estimated to avoid 1,526 (1,253-1,789) and 259 (132-501) premature deaths attributable to long-term exposure to PM2.5 and O3 in Hainan in 2035, respectively.

Modeling the Formation of Organic Compounds across Full Volatility Ranges and Their Contribution to Nanoparticle Growth in a Polluted Atmosphere.

Nanoparticle growth influences atmospheric particles' climatic effects, and it is largely driven by low-volatility organic vapors. However, the magnitude and mechanism of organics' contribution to nanoparticle growth in polluted environments remain unclear because current observations and models cannot capture organics across full volatility ranges or track their formation chemistry. Here, we develop a mechanistic model that characterizes the full volatility spectrum of organic vapors and their contributions to nanoparticle growth by coupling advanced organic oxidation modeling and kinetic gas-particle partitioning. The model is applied to Nanjing, a typical polluted city, and it effectively captures the volatility distribution of low-volatility organics (with saturation vapor concentrations <0.3 µg/m3), thus accurately reproducing growth rates (GRs), with a 4.91% normalized mean bias. Simulations indicate that as particles grow from 4 to 40 nm, the relative fractions of GRs attributable to organics increase from 59 to 86%, with the remaining contribution from H2SO4 and its clusters. Aromatics contribute much to condensable organic vapors (∼37%), especially low-volatility vapors (∼61%), thus contributing the most to GRs (32-46%) as 4-40 nm particles grow. Alkanes also contribute 19-35% of GRs, while biogenic volatile organic compounds contribute minimally (<13%). Our model helps assess the climatic impacts of particles and predict future changes.

Sources of Organic Aerosol in China from 2005 to 2019: A Modeling Analysis.

Organic aerosol (OA) is a key component of fine particulate matter (PM2.5) and affects the human health and leads to climate change. With strict control measures for air pollutants during the last decade, the OA concentration in China declined slowly, while its sources remain unclear. In this study, we simulate the primary OA (POA) and secondary OA (SOA) concentrations from 2005 to 2019 with a state-of-the-art air quality model, Community Multiscale Air Quality (CMAQ, version 5.3.2) coupled with a Two-Dimensional Volatility Basis Set (2D-VBS) module, and a long-term emission inventory of full-volatility organic compounds in China and conduct source apportionment and sensitivity analysis. The simulation results show that, from 2005 to 2019, the OA concentration in China decreased from 24.0 to 12.8 µg/m3 with most of the reduction from POA. The OA pollution from residential biomass burning declined 75% from 2005 to 2019, while it is still the major OA source in China. OA pollution from VCP increased by more than 2-fold and became the largest SOA source in China. From 2014 to 2019, the NOx control in China slightly offset the decrease of SOA concentration due to elevated oxidation capacity.

Extreme Emission Reduction Requirements for China to Achieve World Health Organization Global Air Quality Guidelines.

A big gap exists between current air quality in China and the World Health Organization (WHO) global air quality guidelines (AQG) released in 2021. Previous studies on air pollution control have focused on emission reduction demand in China but ignored the influence of transboundary pollution, which has been proven to have a significant impact on air quality in China. Here, we develop an emission-concentration response surface model coupled with transboundary pollution to quantify the emission reduction demand for China to achieve WHO AQG. China cannot achieve WHO AQG by its own emission reduction for high transboundary pollution of both PM2.5 and O3. Reducing transboundary pollution will loosen the reduction demand for NH3 and VOCs emissions in China. However, to meet 10 µg·m-3 for PM2.5 and 60 µg·m-3 for peak season O3, China still needs to reduce its emissions of SO2, NOx, NH3, VOCs, and primary PM2.5 by more than 95, 95, 76, 62, and 96% respectively, on the basis of 2015. We highlight that both extreme emission reduction in China and great efforts in addressing transboundary air pollution are crucial to reach WHO AQG.

Drivers of High Concentrations of Secondary Organic Aerosols in Northern China during the COVID-19 Lockdowns.

During the COVID-19 lockdown in early 2020, observations in Beijing indicate that secondary organic aerosol (SOA) concentrations increased despite substantial emission reduction, but the reasons are not fully explained. Here, we integrate the two-dimensional volatility basis set into a state-of-the-art chemical transport model, which unprecedentedly reproduces organic aerosol (OA) components resolved by the positive matrix factorization based on aerosol mass spectrometer observations. The model shows that, for Beijing, the emission reduction during the lockdown lowered primary organic aerosol (POA)/SOA concentrations by 50%/18%, while deteriorated meteorological conditions increased them by 30%/119%, resulting in a net decrease in the POA concentration and a net increase in the SOA concentration. Emission reduction and meteorological changes both led to an increased OH concentration, which accounts for their distinct effects on POA and SOA. SOA from anthropogenic volatile organic compounds and organics with lower volatility contributed 28 and 62%, respectively, to the net SOA increase. Different from Beijing, the SOA concentration decreased in southern Hebei during the lockdown because of more favorable meteorology. Our findings confirm the effectiveness of organic emission reductions and meanwhile reveal the challenge in controlling SOA pollution that calls for large organic precursor emission reductions to rival the adverse impact of OH increase.

Yinma Jiedu Granule attenuates LPS-induced acute lung injury in rats via suppressing inflammation level.

ETHNOPHARMACOLOGICAL RELEVANCE: Yinma Jiedu Granule (YMJD) is a traditional Chinese patent medicine (CPM), which has been proved to have anti-inflammatory effects and therapeutical effects on obstructive pulmonary disease. AIM OF STUDY: The purpose of the current investigation is to find out if YMJD can alleviate acute lung injury (ALI) induced by lipopolysaccharide (LPS) in rats and its underlying mechanisms. MATERIALS AND METHODS: Rats were treated with either vehicle or YMJD for 14 consecutive days, and 2 h after the last administration, the rat model of ALI was induced by the intratracheal instillation of LPS. High performance liquid chromatography (HPLC) was applied for the fingerprint analysis of YMJD. The efficacy and molecular mechanisms were investigated. RESULTS: The results showed that treatment with YMJD improved the general state of rats, reduced weight loss and serum lactate (LA) levels, attenuated pulmonary edema and pathological damage of the lung tissue. Moreover, we found that YMJD effectively decreased the infiltration of white blood cells (WBC), lymphocytes (LYM), mononuclear cells (MON) and neutrophils (NEUT) in bronchoalveolar lavage fluid (BALF), reduced the concentration of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) and inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in the lung tissue. Additionally, we found that YMJD could significantly increase the activity of superoxide dismutase (SOD) and reduce the malondialdehyde (MDA) level in the lung tissue. By employing RNA-sequencing, we have identified that JAK2/STAT1 is an important pathway that is involved in the lung protection of YMJD, and further Western blot assay verified that YMJD could effectively inhibit the activation of the JAK2/STAT1 pathway. CONCLUSIONS: YMJD could attenuate LPS-induced ALI through suppressing inflammation and oxidative stress in the lung tissue of rats, associating with the inhibition of JAK2/STAT1 activation. These findings provide evidence for the clinical use of YMJD for treatment of inflammatory pulmonary diseases like ALI.

Nitrogen isotopes suggest agricultural and non-agricultural sources contribute equally to NH3 and NH4+ in urban Beijing during December 2018.

Agricultural and non-agricultural sources emission contribute to atmospheric ammonia (NH3) and particulate ammonium (NH4+). However, our understanding on the sources of NH3 and NH4+ in PM2.5 (particles smaller than 2.5 µm) during the winter period in the urban atmosphere is limited. Here, we measured the concentrations and stable nitrogen isotopic composition (δ15N) of NH3 and NH4+ in parallel during December 2018 in urban Beijing to assess the non-agricultural and agricultural sources contributions to NH3 and NH4+ in ambient air based on the Chemical Transport Model (CTM), a Bayesian isotope mixing model (SIMMR), and the δ15N signatures that we developed. Our study found weekly NH4+ and NH3 concentrations were on average 2.5 ± 1.4 µg m-3 and 3.8 ± 1.7 µg m-3, respectively during December 2018. Weekly concentration weighted δ15N(NH4+) values ranged from 4.5‰ to 13.7‰ with an average value of 8.2 ± 3.9‰ during December 2018. After accounting for nitrogen isotopic fractionation from NH3 gas to NH4+ conversion, initial δ15N(NH3) values ranged from -22.5‰ to -12.8‰ with an average value of -17.4 ± 3.5‰. Further, weekly measured δ15N(NH3) values ranged from -22.2‰ to -10.2‰ (after correction) with an average value of -15.6 ± 5.3‰ during December 2018. Results from two different isotope-based method showed non-agricultural sources contributed 31.2%-63.1%, with an average value of 47.5 ± 14.6%, to NH4+ and 32.3%-71.2%, with an average of 53.4 ± 16.1%, to ambient NH3 during December 2018 in Beijing. Results from CMAQ-ISAM suggest non-agricultural sources contributed on average 66.2 ± 1.9% to ambient NH4+ and 66.4 ± 1.9% to ambient NH3 during December 2018. Results from this study suggest that agricultural and non-agricultural sources nearly equally contributed to NH3 and NH4+ in urban Beijing during December 2018 with an uncertainty range of 13%-19% between isotope-based methods and CTM method.

The comparison of the efficacy and safety of fractional 1064 nm Nd:YAG picosecond laser and nonablative fractional 1565 nm laser in the treatment of enlarged pores: A prospective split-face study.

BACKGROUND AND OBJECTIVES: To compare the efficacy and safety of fractional 1064 nm Nd:YAG picosecond laser and nonablative fractional 1565 nm laser in the treatment of enlarged pores. STUDY DESIGN/MATERIALS AND METHODS: Twenty patients received five monthly treatments at months 0, 1, 2, 3, and 4 and were followed up at months 5, 6, and 7. All patients were treated by fractional 1064 nm Nd:YAG picosecond laser (FxPico) on the left face, and nonablative fractional 1565 nm laser (ResurFx) on the right face as a control. RESULTS: For the 19 patients who completed the study, both sides demonstrated significant improvement on pore counts (p < 0.01), while there was no significant difference between the two sides 3 months after the final treatment (p = 0.092). Excellence rate on the FxPico side (57.9%) was significantly better than the ResurFx side (36.8%) (p < 0.05). Sebum secretion and porphyrin value significantly decreased on both sides after five treatments and there was a higher reduction of sebum level on the ResurFx side. There was no difference between the two therapies in terms of overall satisfaction. Pain of treatment for the ResurFx side (average VAS 4.45 ± 1.60) is significantly higher than that for the FxPico side (average visual analog scale [VAS] 1.48 ± 1.36) (p < 0.001). Erythema, edema, and petechiae were common adverse effects and were mild to moderate. There was significantly higher incidence of hyperpigmentation for the ResurFx side (52.6%) compared with that for the FxPico side (5.3%) (p < 0.001). CONCLUSION: Fractional 1064 nm Nd:YAG picosecond laser and nonablative fractional 1565 nm laser both are effective, efficient, and safe treatment regimens for enlarged pores, while fractional 1064 nm Nd:YAG picosecond laser has better clinical response with less treatment pain, shorter recovery period and much lower induction of hyperpigmentation.

Inhibition of CXCR2 enhances CNS remyelination via modulating PDE10A/cAMP signaling pathway.

CXC chemokine receptor 2 (CXCR2) plays an important role in demyelinating diseases, but the detailed mechanisms were not yet clarified. In the present study, we mainly investigated the critical function and the potential molecular mechanisms of CXCR2 on oligodendrocyte precursor cell (OPC) differentiation and remyelination. The present study demonstrated that inhibiting CXCR2 significantly enhanced OPC differentiation and remyelination in primary cultured OPCs and ethidium bromide (EB)-intoxicated rats by facilitating the formation of myelin proteins, including PDGFRα, MBP, MAG, MOG, and Caspr. Further investigation identified phosphodiesterase 10A (PDE10A) as a main downstream protein of CXCR2, interacting with the receptor to regulate OPC differentiation, in that inhibition of CXCR2 reduced PDE10A expression while suppression of PDE10A did not affect CXCR2. Furthermore, inhibition of PDE10A promoted OPC differentiation, whereas overexpression of PDE10A down-regulated OPC differentiation. Our data also revealed that inhibition of CXCR2/PDE10A activated the cAMP/ERK1/2 signaling pathway, and up-regulated the expression of key transcription factors, including SOX10, OLIG2, MYRF, and ZFP24, that ultimately promoted remyelination and myelin protein biosynthesis. In conclusion, our findings suggested that inhibition of CXCR2 promoted OPC differentiation and enhanced remyelination by regulating PDE10A/cAMP/ERK1/2 signaling pathway. The present data also highlighted that CXCR2 may serve as a potential target for the treatment of demyelination diseases.

An acid rain-friendly NH3 control strategy to maximize benefits toward human health and nitrogen deposition.

Ammonia (NH3) abatement remains controversial in China owing to its effectiveness in reducing PM2.5 pollution and nitrogen deposition but with the potential risk of promoting acid rain formation, necessitating scientific guidance. Here, we propose a novel method for designing an NH3 control strategy to mitigate both air pollution and nitrogen deposition without significantly exacerbating acid rain. This method involves extending the response surface model (RSM) to deposition using a delicately developed polynomial response function of deposition (i.e., dep-RSM). The Yangtze River Delta (YRD) dep-RSM application reveals that 16 out of 41 cities have NH3 control potentials from 15 % to 71 %. Excellent NH3 control potentials have been noted between April and June (78 %-92 %). From 2013 to 2017, the effective SO2 and NOx control significantly reduced wet sulfur and oxidized nitrogen deposition, providing considerable NH3 abatement potentials (15 %-24 %) to further reduce PM2.5 and nitrogen deposition by up to 2 % and 9 %, respectively, without acid rain exacerbation (the wet neutralization factor was maintained). Additionally, 57 % and 73 % NH3 emission reduction potentials were obtained under acid rain constraints with 75 % and 86 % reductions in the other precursors to reduce the average PM2.5 concentration below 25 and 15 µg/m3, and an additional 8408 and 14,459 premature deaths could only be avoided at an extra cost of 8.7 and 19.7 billion CNY, respectively. Meanwhile, the N deposition considerably reduced by 10 and 13 kgN/ha·yr. However, the YRD region could still simultaneously obtain substantial amounts of PM2.5 and N deposition mitigation using the strategy proposed herein. The expanded optimization system can be directly adopted by policymakers to implement coordinated control in regions or countries facing the same NH3 control conundrum.

Synergetic PM2.5 and O3 control strategy for the Yangtze River Delta, China.

PM2.5 concentrations have dramatically reduced in key regions of China during the period 2013-2017, while O3 has increased. Hence there is an urgent demand to develop a synergetic regional PM2.5 and O3 control strategy. This study develops an emission-to-concentration response surface model and proposes a synergetic pathway for PM2.5 and O3 control in the Yangtze River Delta (YRD) based on the framework of the Air Benefit and Cost and Attainment Assessment System (ABaCAS). Results suggest that the regional emissions of NOx, SO2, NH3, VOCs (volatile organic compounds) and primary PM2.5 should be reduced by 18%, 23%, 14%, 17% and 33% compared with 2017 to achieve 25% and 5% decreases of PM2.5 and O3 in 2025, and that the emission reduction ratios will need to be 50%, 26%, 28%, 28% and 55% to attain the National Ambient Air Quality Standard. To effectively reduce the O3 pollution in the central and eastern YRD, VOCs controls need to be strengthened to reduce O3 by 5%, and then NOx reduction should be accelerated for air quality attainment. Meanwhile, control of primary PM2.5 emissions shall be prioritized to address the severe PM2.5 pollution in the northern YRD. For most cities in the YRD, the VOCs emission reduction ratio should be higher than that for NOx in Spring and Autumn. NOx control should be increased in summer rather than winter when a strong VOC-limited regime occurs. Besides, regarding the emission control of industrial processes, on-road vehicle and residential sources shall be prioritized and the joint control area should be enlarged to include Shandong, Jiangxi and Hubei Province for effective O3 control.

Identify Bitter Peptides by Using Deep Representation Learning Features.

A bitter taste often identifies hazardous compounds and it is generally avoided by most animals and humans. Bitterness of hydrolyzed proteins is caused by the presence of bitter peptides. To improve palatability, bitter peptides need to be identified experimentally in a time-consuming and expensive process, before they can be removed or degraded. Here, we report the development of a machine learning prediction method, iBitter-DRLF, which is based on a deep learning pre-trained neural network feature extraction method. It uses three sequence embedding techniques, soft symmetric alignment (SSA), unified representation (UniRep), and bidirectional long short-term memory (BiLSTM). These were initially combined into various machine learning algorithms to build several models. After optimization, the combined features of UniRep and BiLSTM were finally selected, and the model was built in combination with a light gradient boosting machine (LGBM). The results showed that the use of deep representation learning greatly improves the ability of the model to identify bitter peptides, achieving accurate prediction based on peptide sequence data alone. By helping to identify bitter peptides, iBitter-DRLF can help research into improving the palatability of peptide therapeutics and dietary supplements in the future. A webserver is available, too.

Responses of nitrogen and sulfur deposition to NH3 emission control in the Yangtze River Delta, China.

NH3 emission control has proven to be of great importance in reducing PM2.5 concentrations in China, while how it affects nitrogen/sulfur (N/S) deposition is still unclear. This study expanded the response surface model method to quantify the responses of N/S deposition to the emission control of precursors (NOx, SO2, NH3, VOCs and primary PM2.5) in the Yangtze River Delta, China. NH3 control was found to have higher efficiency in reducing N/S deposition than NOx and SO2 alone. The reduced N deposition response to NH3 emission control was higher in the northern part of the YRD region, whereas oxidized N deposition decreased sharply in the region with a low N critical load. Synergetic effect was found in reducing N deposition when we controlled the NH3 and NOx emissions simultaneously. Compared with the sum effect of individual NH3 and NOx emission control, the extra benefits from the synergy controls accounted for 4.4% (1.23 kg N·ha-1·yr-1) of the total N deposition, of which 81% came from the oxidized N deposition. The YRD region could receive the largest synergetic effect with a 1:1 ratio of NOx:NH3 emission reduction. The NH3 emission control increases the dry deposition of acid substances and worsens acid rain though it reduces the wet S/oxidized N deposition. These findings highlight the effectiveness of NH3 emission control and suggest a multi-pollutant control strategy for reducing N/S deposition. The response surface model method for deposition also provides a reference for other regions in China and other countries.