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Sizes and number concentrations are critical parameters for the impact of atmospheric particles on climate and human health. However, comprehensive studies focusing on size‐resolved particle number (PN) emissions from various sectors are scarce. This study aims to fill this research gap by developing sectoral size‐resolved PN emissions for major species including sulfate, organic mass (OM), and black carbon (BC). The size‐resolved emission profiles derived from various measurements in the literature were integrated with a particle mass emission inventory (EI) for 13 major sectors in the Yangtze River Delta region of China as a case study. The particle number size distribution (PNSD) of emitted particles exhibited two distinct peaks: one at approximately 10 nm and the other in the range of 40–60 nm. The primary contributors to PN emissions in the region in 2017 were power plants, gasoline vehicles, diesel vehicles, and cooking sources. In terms of species, OM dominated PN emissions, followed by primary sulfate and then BC. A regional size‐resolved aerosol model employing the size‐resolved PN EI developed here (referred to as the BIN‐SPE experiment) provided reasonably accurate temporal variations of the total PN concentration and captured the PNSD within the size range of 10–300 nm. Uncertainty analysis of sectoral PN emissions across size ranges was carried out and the performance of the BIN‐SPE experiment was compared with those of three commonly used PN emission parameterizations. Our model evaluations highlight future needs for in‐depth investigations into more advanced size‐resolved emissions and secondary OM formation mechanisms. Plain Language Summary: Various sources such as power plants, vehicles, cooking, and others emit numerous small particles. Quantifying their sizes and number emissions is crucial for understanding atmospheric particle number size distribution and its impacts on climate and health. However, few studies comprehensively address sectoral size‐resolved particle number emissions, with most focusing on global scales or single source. This study couples size‐resolved emission profiles reported in literature for 13 major sectors with mass emission inventories to quantify sectoral size‐resolved particle number emissions with speciation for the Yangtze River Delta region in China. The particle number emissions exhibit a bimodal distribution with peaks at approximately 10 and 40–60 nm. Primary contributors are power plants, gasoline vehicles, diesel vehicles, and cooking sources. In terms of species, organic matter dominates particle number emissions, followed by primary sulfate and black carbon. Notably, the peak in emissions with sizes less than 20 nm reconciles the disparity between modeled and observed distributions. To the best of our knowledge, this study represents the first comprehensive examination of sectoral particle number emissions with speciation in China. The method and data sets utilized in this study can be employed to quantify particle number emissions in other regions and are instrumental for impact assessments. Key Points: An emission profile‐based method is applied to quantify sectoral size‐resolved particle number emissions with speciationVehicles, power plants, and cooking dominate bimodal particle number emissions, with organics and primary sulfate as major speciesProminent particle number emissions with sizes less than 20 nm substantially reduce model‐observation disparities [ABSTRACT FROM AUTHOR]

Background: To explore the association between radiation after surgery and the 5-year overall survival (OS) and 5-year cancer-specific survival (CSS) in patients with Wilms tumor. Methods: In this cohort study, 1564 participants were identified from the Surveillance, Epidemiology, and End Results (SEER) database. The univariate and multivariable COX proportional risk model as well as competitive risk model were used to explore the covariates associated with 5-year OS and 5-year CSS of patients with Wilms tumor and the correlation between radiation after surgery and 5-year OS or 5-year CSS of patients with Wilms tumor, respectively. The Kaplan-Meier curves of participants were plotted. Results: The median follow-up was 126.00 (84.00, 178.00) months. Patients receiving surgery had higher 5-year survival probability than those not receiving surgery, while participants receiving radiation after surgery showed poor 5-year survival than those not. After adjusting for covariates including age and SEER stage, increased risk of 5-year overall mortality in patients with Wilms tumor [hazard ratio (HR) = 1.62, 95% confidence interval (CI): 1.10–2.41). After the adjustment for confounding factors including age, SEER stage and ethnicity, increased risk of 5-year cancer-specific mortality of patients with Wilms tumor was observed in those receiving radiation after surgery (HR = 1.77, 95%CI: 1.13–2.79). Conclusion: Radiation after surgery was associated with poor prognosis of patients with Wilms tumor, which indicated that the clinicians should assess whether the patient was suitable for using radiation after surgery. [ABSTRACT FROM AUTHOR]

Recent experiments have revealed a vital nucleation process of iodic acid (HIO 3) and iodous acid (HIO 2) under marine boundary layer conditions. However, HIO 3 –HIO 2 nucleation may not effectively drive the observed rapid new particle formation (NPF) in certain coastal regions influenced by urban air masses. Dimethylamine (DMA) is a promising basic precursor to enhance nucleation considering its strong ability to stabilize acidic clusters and the wide distribution in marine atmosphere, while its role in HIO 3 –HIO 2 nucleation remains unrevealed. Hence, a method combining quantum chemical calculations and Atmospheric Cluster Dynamics Code (ACDC) simulations was utilized to study the HIO 3 –HIO 2 –DMA nucleation process. We found that DMA can preferentially accept the proton from HIO 3 as a basic precursor in the most stable configurations of HIO 3 –HIO 2 –DMA clusters. Kinetically, the participation of DMA in the cluster formation pathways of the iodine oxoacid system could be significant at the 10 -1 to 1 pptv level of [DMA]. Furthermore, DMA can enhance the cluster formation rates of the HIO 3 –HIO 2 system in marine and polar regions near DMA sources more than 10 3 -fold. Compared to the classical nucleation mechanism, the HIO 3 –HIO 2 –DMA mechanism exhibits strong nucleation ability, worthy of consideration as a promising mechanism in marine and polar regions rich in amine sources. The newly proposed HIO 3 –HIO 2 –DMA ternary mechanism might provide an explanation for some missing fluxes of atmospheric iodine particles. [ABSTRACT FROM AUTHOR]

Recent experiment (He et al, 2021, Science) revealed a vital nucleation process of iodic acid (HIO3) and iodous acid (HIO2) under the marine boundary layer conditions. However, HIO3-HIO2 nucleation cannot effectively derive the observed rapid new particle formation (NPF) in broad marine regions. Dimethylamine (DMA) is a promising basic precursor to enhance nucleation considering its strong ability to stabilize acidic clusters and the wide distribution in marine atmosphere, while its role in HIO3-HIO2 nucleation remains unrevealed. Hence, a method combining quantum chemical calculations and Atmospheric Cluster Dynamics Code (ACDC) simulations was utilized to study the HIO3-HIO2-DMA nucleation process. We found that DMA can compete with HIO2 to accept the proton from HIO3 as a basic precursor in the most stable configurations of HIO3-HIO2-DMA clusters. DMA can significantly enhance the cluster formation rates of HIO3-HIO2 kinetically for more than 103-fold in regions with abundant amine and scarce iodine based on combined factors of high nucleation ability and high concentration of DMA. Furthermore, the iodine oxoacids nucleation enhanced by DMA may explain the sources of rapid NPF events under different conditions corresponding to multiple ocean regions, which can provide important inspirations to understand the frequent and intensive NPF events in broad marine regions. [ABSTRACT FROM AUTHOR]