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Background: Acute liver injury is a common pathological feature of various clinical diseases, and prolonged liver damage can lead to fibrosis and even liver failure. Studies have reported that the vagus nerve can repair liver injury through the regulation of the cholinergic anti-inflammatory pathway. However, there is limited research on the regulation of interleukin-22 and its role in liver injury. This study aimed to investigate the regulatory effect of vagus nerve receptor α7nAChR on interleukin-22 and whether this regulatory axis can protect against liver injury., Methods: Rats and the human liver cell line L-02 were treated with carbon tetrachloride to simulate acute liver injury. The experimental groups were divided as follows: control group, model group, model + PNU282987 group, model + MLA group, and MLA group. After the intervention, blood samples, liver tissues, and cells were collected to assess liver function (AST, ALT), inflammation (TNF-α, IL-6,), α7nAChR and interleukin-22 concentrations, apoptosis levels (Bax, BCL-2), and proliferation markers (Ki-67, PCNA) using quantitative real time PCR, Western blot, immunohistochemistry and ELISA., Results: The results indicated that carbon tetrachloride intervention led to compensatory increases in interleukin-22 while inhibition of α7nAChR decreased interleukin-22 concentrations and exacerbated the injury marked by high levels of AST, ALT and TNF-α,IL-6. Exogenous administration of a vagus nerve agonist alleviated liver injury and was accompanied by an increase in interleukin-22 levels. In rescue experiments, simultaneous inhibition of vagus nerve receptors and administration of exogenous interleukin-22 reduced liver injury and significantly enhanced liver regeneration. Conversely, activation of vagus nerve receptors while inhibiting interleukin-22 aggravated liver injury., Conclusion: This study confirms that vagus nerve receptor α7nAChR can promote liver regeneration and protect against carbon tetrachloride-induced liver injury by regulating interleukin-22., 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 © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Smart electromagnetic interference (EMI) shielding materials with adjustable shielding efficiency (SE) hold immense importance in the field of wearable and switchable EMI shielding. However, existing materials often suffer from a constrained tunability range and inadequate stability. In this study, a highly stretchable conductive framework is fabricated by integrating Ni-doped laser-induced graphene (LIG/Ni) with silicone. Through meticulous manipulation of the LIG scanning trajectory and Ni nanoparticle (NP) deposition parameters, ordered and dense conductive pathways were formed. This ordered structure preserves the graphene's structural coherence and conductivity along the axis perpendicular to stretching, while graphene parallel to the stretching direction forms random connections, resulting in the effective regulation of electrical conductivity. Under a 200% strain, the electrical conductivity dropped to a minimum of 1.07 S/cm, and the average SE in the X-band was reduced to 2.33 dB. Upon strain release, the conductive network rapidly reconfigured, boosting conductivity to 63.6 S/m and an enhanced SE of 68.12 dB. With its highly reversible conductive network, this composite exhibits exceptional cycling stability and an expansive range of adjustable SE, thereby holding immense practical value for versatile electromagnetic protection applications.

Metabolism of Branched-chain amino acids (BCAAs) is essential for the nutrient necessities in mammals. Catalytic enzymes serve to direct the whole-body BCAAs oxidation which involve in the development of various metabolic disorders. The reprogrammed metabolic elements are also responsible for malignant oncogenic processes, and favor the formation of distinctive immunosuppressive microenvironment surrounding different cancers. The impotent immune surveillance related to BCAAs dysfunction is a novel topic to investigate. Here we focus on the BCAA catalysts that contribute to metabolic changes and dysregulated immune reactions in cancer progression. We summarize the current knowledge of BCAA catalyzation, highlighting the interesting roles of BCAA metabolism in the treatment of cancers., 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 © 2024 Elsevier Inc. All rights reserved.)

"Low-lying" posterior communicating artery (PCoA) aneurysms require great attention in surgical clipping due to their distinct anatomical characteristics. In this study, we propose an easy method to immediately recognize "low-lying" PCoA aneurysms in neurosurgical practice. A total of 89 cases with "low-lying" PCoA aneurysms were retrospectively analyzed. All patients underwent preoperative digital subtraction angiography (DSA) examinations and microsurgical clipping. Cases were classified into the "low-lying" and regular groups based on intraoperative findings. The distance- and angle-relevant parameters that reflected the relative location of the aneurysms and tortuosity of the internal carotid artery were measured using 3D-DSA images. The data were sequentially integrated into a mathematical analysis to obtain the prediction model. Finally, we proposed a novel mathematical formula to preoperatively predict the existence of "low-lying" PCoA aneurysms with great accuracy. Neurosurgeons might benefit from this model, which enables them to directly identify "low-lying" PCoA aneurysms and make appropriate surgical decisions accordingly., (© 2024. The Author(s).)

Key Message: Calcium polypeptide plays a key role during cadmium stress responses in rice, which is involved in increasing peroxidase activity, modulating pectin methylesterase activity, and regulating cell wall by reducing malondialdehyde content. Cadmium (Cd) contamination threatens agriculture and human health globally, emphasizing the need for sustainable methods to reduce cadmium toxicity in crops. Calcium polypeptide (CaP) is a highly water-soluble small molecular peptide acknowledged for its potential as an organic fertilizer in promoting plant growth. However, it is still unknown whether CaP has effects on mitigating Cd toxicity. Here, we investigated the effect of CaP application on the ability to tolerate toxic Cd in rice. We evaluated the impact of CaP on rice seedlings under varying Cd stress conditions and investigated the effect mechanism of CaP mitigating Cd toxicity by Fourier transform infrared spectroscopy (FTIR), fluorescent probe dye, immunofluorescent labeling, and biochemical analysis. We found a notable alleviation of Cd toxicity by reduced malondialdehyde content and increased peroxidase activity. In addition, our findings reveal that CaP induces structural alterations in the root cell wall by modulating pectin methylesterase activity. Altogether, our results confirm that CaP not only promoted biomass accumulation but also reduced Cd concentration in rice. This study contributes valuable insights to sustainable strategies for addressing Cd contamination in agricultural ecosystems., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Esophageal malignancies have a high morbidity rate worldwide, and minimally invasive surgery has emerged as the primary approach for treating esophageal cancer. In recent years, there has been increasing discussion about the potential of employing inflatable mediastinoscopic and laparoscopic approaches as an option for esophagectomy. Building on the primary modification of the inflatable mediastinoscopic technique, we introduced a secondary modification to further minimize surgical trauma., Methods: We conducted a retrospective analysis of patients who underwent inflatable mediastinoscopy combined with laparoscopic esophagectomy at the Second Affiliated Hospital of Naval Medical University from March 2020 to March 2023. The patients were allocated to the following two groups: the traditional (primary modification) group, and the secondary modification group. Operation times, intraoperative bleeding, and postoperative complications were compared between the groups., Results: The procedure was successfully performed in all patients, and conversion to open surgery was not required in any case. There were no statistically significant differences in the surgical operation time, intraoperative bleeding, number of dissected lymph nodes, and rate of postoperative anastomotic leakage between the two groups. However, a statistically significant difference was observed in the length of the mobilized esophagus between the two groups. The mobilization of esophagus to the level of diaphragmatic hiatus via the cervical incision was successfully achieved in more patients in the secondary modification group than the primary modification group., Conclusions: Inflatable mediastinoscopy combined with single-incision plus one-port laparoscopic esophagectomy is a safe and effective surgical procedure. The use of a 5-mm flexible endoscope, ultra-long five-leaf forceps, and LigaSure Maryland forceps facilitates esophageal mobilization and lymph node dissection through a single cervical incision., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-24-309/coif). The authors have no conflicts of interest to declare., (2024 Journal of Thoracic Disease. All rights reserved.)

HNRNPA2B1 and HNRNPR stabilize ASCL1 mRNA in neuroblastoma, but whether their regulatory effects depend on m6A modification and whether their function involves ASCL1 remain unknown. This study investigated the m6A-dependent binding of HNRNPA2B1 and HNRNPR to ASCL1 and subsequent regulation, as well as the expression, clinical significance, and function of HNRNPA2B1 and HNRNPR in neuroblastoma. We revealed that METTL14 mediated ASCL1 m6A modification to stabilize ASCL1. HNRNPA2B1 and HNRNPR significantly enriched ASCL1 mRNA by binding to the 5' and 3' untranslated regions, respectively, and METTL14 knockdown reduced this enrichment. Mutations in m6A sites in the untranslated regions of ASCL1 mRNA considerably decreased probe capacity to engage HNRNPA2B1 and HNRNPR. HNRNPR interacts with IGF2BP1, and knocking down either impaired binding to ASCL1 mRNA. HNRNPA2B1 and HNRNPR knockdown suppressed neuroblastoma cell growth and invasion, while ASCL1 overexpression restored these effects. The high HNRNPA2B1 and HNRNPR expression in neuroblastoma correlated with ASCL1 expression. Thus, HNRNPA2B1 and HNRNPR bind and stabilize ASCL1 mRNA in an m6A-dependent manner to promote neuroblastoma progression. This study not only discovered a new mechanism underlying the high ASCL1 expression in neuroblastoma but also identified the HNRNPA2B1/HNRNPR/ASCL1 axis as a promising target for inhibiting neuroblastoma progression., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose: A novel 18 F-radiolabeled somatostatin analogue, [Al 18 F]NODA-MPAA-HTA, was synthesized and evaluated for positron emission tomography (PET) imaging of Neuroendocrine tumors (NETs). [Al 18 F]NODA-MPAA-HTA was designed and synthesized by conjugating 18 F nuclide with a modified KE108 peptide, a somatostatin analog with high affinity for all five subtypes of somatostatin receptors (SSTR 1-5), through coupling a bifunctional chelator (NODA) to target somatostatin receptor (SSTR) positive tumors., Methods: The amino group of KE108 peptide, a SSTRs-targeting pharmacophore, was conjugated with the carboxyl group of NODA by a condensation reaction to obtain the labeling precursor of [Al 18 F]NODA-MPAA-HTA, in which its precursor was obtained through Fmoc solid-phase methods. A novel methodology for Al 18 F labeling of chelating agent-biomolecule conjugates was used to synthesize [Al 18 F]NODA-MPAA-HTA. In vitro stabilities of [Al 18 F]NODA-MPAA-HTA were evaluated by incubating it in saline or bovine serum for 2 h. Ex vivo biodistribution and in vivo imaging of [Al 18 F]NODA-MPAA-HTA were further investigated to evaluate its SSTRs targeting ability and feasibility for the diagnosis of NETs using PET imaging., Results: [Al 18 F]NODA-MPAA-HTA was synthesized using a one-step 18 F-AlF labeling procedure resulting in moderate radiochemical yield (60-80 %, non-decay corrected) and high radiochemical purity (>95 %). It exhibited good hydrophilicity and excellent stability in vitro, with a molar activity of 122 GBq/μmol. At 30 min and 60 min, the uptake of [Al 18 F] NODA-MPAA-HTA by HEK293-SSTR2 cells was 5.47 ± 0.97 %/105 cells and 12.11 ± 0.32 %/105 cells, respectively. The affinity of [Al 18 F]NODA-MPAA-HTA for SSTR2 was determined to be 8.77 ± 1.14 nM. In micro-PET imaging of HEK293-SSTR2 tumor-bearing mice, [Al 18 F]NODA-MPAA-HTA showed high tumor uptake of radioactivity and a high tumor-to-muscle ratio. Biodistribution results confirmed that radioactivity uptake in the tumor was significantly higher than that in the muscle by more than five-fold (P<0.001). Furthermore, the relatively low bone uptake of [Al 18 F]NODA-MPAA-HTA suggested that defluorination did not occur in vivo. These preliminary results provide experimental evidence for further study of Al 18 F-labeled somatostatin analogues as tumor probes for PET imaging of NETs., Conclusion: Fluorine-18 is widely used as a radionuclide for the production of radiopharmaceuticals for positron emission tomography (PET). Due to its short half-life (T1/2,109.8 min), its ease of production will facilitate the widespread dissemination of this radiopharmaceutical. A high-quality [Al 18 F]NODA-MPAA-HTA was synthesized with satisfactory yield. This radiopharmaceutical demonstrated higher tumor uptake and better tumor-to-muscle contrast, resulting to excellent image quality. These findings suggest that the novel 18 F-labeled somatostatin analogue, [Al 18 F]NODA-MPAA-HTA, is a promising tool for PET imaging of NETs., 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 The Author(s). Published by Elsevier B.V. All rights reserved.)

Chloride-ion batteries (CIBs) have drawn growing attention in large-scale energy storage applications owing to their comprehensive merits of high theoretical energy density, dendrite-free characteristic, and abundance of chloride-containing materials. Nonetheless, cathodes for CIBs are plagued by distinct volume effect and sluggish Cl - diffusion kinetics, leading to inferior rate capability and short cycling life. Herein, an unconventional Ni 5 Ti-Cl LDH is reported with a high nickel ratio as a cathode material for CIB. The reversible capacity of Ni 5 Ti-Cl LDH retains 127.9 mAh g -1 over 1000 cycles at a large current density of 1000 mA g -1 , which exceeds that of ever reported CIBs, with extraordinary low volume change of 1.006% during a whole charge/discharge process. Such superior Cl-storage performance is attributed to synergetic contributions consisting of high redox activity from Ni 2+ /Ni 3+ and pinning Ti that restrains local structural distortion of LDH host layers and enhances adsorption intensity of chloride atoms during the reversible Cl - intercalation/de-intercalation in LDH gallery, which are revealed by a comprehensive study including X-ray photoelectron spectroscopy, kinetic investigations, and DFT calculations. This work provides an effective strategy to design low-cost LDHs materials for high-performance CIBs, which are also applicable to other types of halide-ion batteries (e.g., fluoride-ion and bromide-ion batteries)., (© 2023 Wiley-VCH GmbH.)

Layered double hydroxides (LDHs) have been intensively investigated as promising cathodes for the new concept chloride ion battery (CIB) with multiple advantages of high theoretical energy density, abundant raw materials and unique dendrite-free characteristics. However, driven by the great compositional diversity, a complete understanding of interactions between metal cations, as well as a synergetic effect between metal cations and lattice oxygen on LDH host layers in terms of the reversible Cl-storage capability, is still a crucial but elusive issue. In this work, we synthesized a series of chloride-inserted trinary Mo x -doped NiCo 2 -Cl LDH ( x = 0, 0.1, 0.2, 0.3, 0.4, and 0.5) with gradient oxygen vacancies as enhanced cathodes toward CIBs. The combination of advanced spectroscopic techniques and theoretical calculations reveals that the Mo dopant facilitates oxygen vacancy formation and varies the valence states of coordinated transition metals, which can not only tune the electronic structure effectively and promote Cl-ion diffusion, but improve the redox activity of LDHs. The optimized Mo 0.3 NiCo 2 -Cl LDH delivers a reversible discharge capacity of 159.7 mA h g -1 after 300 cycles at 150 mA g -1 , which is almost a triple enhancement compared to that of NiCo 2 Cl LDH. The superior Cl-storage of trinary Mo 0.3 NiCo 2 Cl LDH is attributed to the reversible intercalation/deintercalation of chloride ions in the LDH gallery along with the oxidation state changes in Ni 0 /Ni 2+ /Ni 3+ , Co 0 /Co 2+ /Co 3+ and Mo 4+ /Mo 6+ couples. This simple vacancy engineering strategy provides critical insights into the significance of the chemical interaction of various components on LDH laminates and aims to effectively design more LDH-based cathodes for CIBs, which can even be extended to other halide-ion batteries like fluoride ion batteries and bromide ion batteries.

In recent years, advancements in industries such as aerospace, military weaponry, automobiles, locomotives, and shipbuilding have led to a surge in the demand for bent and rolled components, along with increasingly stringent requirements for rolling precision. However, the traditional hydraulic cylinder feeding solution has hindered further enhancements in the accuracy of rolled profile contours. Additionally, owing to variations in profile specifications, material properties, and an assortment of random factors during the forming process, the applicability of existing forming formulas remains limited, rendering them suitable only for profile processing under specific circumstances. To address these challenges, servo electric cylinders have been introduced as a replacement for traditional hydraulic cylinders, and the mechanical structure of a four-roll bending machine has been re-engineered. This innovation has demonstrated the feasibility of employing servo electric cylinders in four-roll CNC bending machines for profile bending, resulting in higher control precision and faster response times, ultimately providing a comprehensive design solution for four-roll CNC bending machines. In response to the limited universality of existing forming formulas, the actual R (profile forming curvature) and d (servo electric cylinder feed) values from the four-roll CNC bending machine have been utilized, and curve fitting methods have been implemented as the foundation for the automatic control model. This approach offers a high degree of universality, making it suitable for a wide range of applications. Moreover, as the number of trials increased, forming precision progressively improved., (© 2023. Springer Nature Limited.)

Blind signatures have been widely applied when privacy preserving is required, and the delegation of blind signature rights and a proxy blind signature (Proxy-BS) become necessary when the signer cannot sign. Existing Proxy-BS schemes are based on traditional cryptographically hard problems, and they cannot resist quantum attacks. Moreover, most current Proxy-BS schemes depend on public key infrastructure (PKI), which leads to high certificate storage and management overhead. To simplify key management and resist quantum attacks, we propose a post-quantum secure identity-based proxy blind signature (ID-Proxy-BS) scheme on a lattice using a matrix cascade technique and lattice cryptosystem. Under the random oracle model (ROM), the security of the proposed scheme is proved. Security shows that the proposed scheme assures security against quantum attacks and satisfies the correctness, blindness, and unforgeability. In addition, we apply the ID-Proxy-BS scheme on a lattice to e-voting and propose a quantum-resistant proxy e-voting system, which is resistant to quantum attacks and achieves the efficiency of e-voting.

Chloride ion batteries (CIBs) have drawn growing attention as attractive candidates for large-scale energy storage technology because of their high theoretical energy densities (2500 W h L -1 ), dendrite-free characteristics and abundance of chloride-containing materials available worldwide. However, the further development of CIBs is greatly limited by sluggish Cl - diffusion and distinct structural variation of cathode materials, resulting in severe decayed capacity and inferior rate performance. Metal-organic framework (MOF) materials possess regular pores/channels and flexible structural designability to accommodate charge carrier ions, but the application of MOFs in anion-type batteries has not been reported. Here, we demonstrate the first example of Ni(dpip) with two different opening sizes of tubular channels serving as the cathode for high performance CIBs. The Ni-based MOF exhibited a stable reversible capacity of 155 mA h g -1 with an admirable low capacity decay of 0.026% per cycle over 500 cycles and superior kinetics with a 10 -10 cm 2 s -1 average diffusion coefficient for chloride ions as well. The high performance of the Ni(dpip) cathode results from the synergetic redox couples of Ni metal nodes and N-ligands, the unique double-channel structure for reversible Cl-storage, and the low chloride diffusion energy barrier. This work switches on the new application of MOF-based materials as cathodes for CIBs., Competing Interests: The authors have declared no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Ozone (O 3 ) is an important greenhouse gas in the atmosphere. Stratospheric ozone protects human beings, but high near-surface ozone concentrations threaten environment and human health. Owing to the uneven distribution of ground-monitoring stations and the low time resolution of polar orbiting satellites, it is difficult to accurately evaluate the refinement and synergistic pollution of near-surface ozone in China. Besides, atmospheric circulation patterns also affect ozone concentrations greatly. In this study, a new generation of geostationary satellite is used to estimate the hourly near-surface ozone concentration with a spatial resolution of 0.05°. First, the Pearson correlation coefficient and maximum information coefficient were used to study the correlation between the top of atmospheric radiation (TOAR) of Himawari-8 satellite and O 3 concentration; seven TOAR channels were selected. Second, based on an interpretable deep learning model, the hourly ozone concentration in China from September 2015 to August 2021 was obtained using the TOAR-O 3 model. Finally, the self-organizing map method was used to determine six major summer weather circulation patterns in China. The results showed that (1) the near-surface O 3 concentration can be accurately estimated; the R 2 (RMSE: μg/m 3 ) values of the daily, monthly, and annual tenfold cross validation results were 0.91 (12.74), 0.97 (5.64), and 0.98 (1.75), respectively. The feature importance of the model showed that the temperature, TOAR, and boundary layer height contributed 38 %, 22 %, and 13 %, respectively. (2) The O 3 concentration showed obvious spatiotemporal difference and gradually increased from 10:00 to 15:00 (Beijing time) every day. In most areas of China, O 3 concentration had increased significantly. (3) The O 3 concentration in northern China was the highest under the circulation pattern of the Meiyu front over the Yangtze River Delta, while in southern China, it was the highest under the circulation pattern of the northeast cold vortex controlling most of 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. Published by Elsevier B.V.)

PM 2.5 (fine particulate matter with aerodynamics diameter <2.5 μm) is the most important component of air pollutants, and has a significant impact on the atmospheric environment and human health. Using satellite remote sensing aerosol optical depth (AOD) to explore the hourly ground PM 2.5 distribution is very helpful for PM 2.5 pollution control. In this study, Himawari-8 AOD, meteorological factors, geographic information, and a new deep forest model were used to construct an AOD-PM 2.5 estimation model in China. Hourly cross-validation results indicated that estimated PM 2.5 values were consistent with the site observation values, with an R 2 range of 0.82-0.91 and root mean square error (RMSE) of 8.79-14.72 μg/m³, among which the model performance reached the optimum value between 13:00 and 15:00 Beijing time (R 2  > 0.9). Analysis of the correlation coefficient between important features and PM 2.5 showed that the model performance was related to AOD and affected by meteorological factors, particularly the boundary layer height. Deep forest can detect diurnal variations in pollutant concentrations, which were higher in the morning, peaked at 10:00-11:00, and then began to decline. High-resolution PM 2.5 concentrations derived from the deep forest model revealed that some cities in China are seriously polluted, such as Xi 'an, Wuhan, and Chengdu. Our model can also capture the direction of PM 2.5 , which conforms to the wind field. The results indicated that due to the combined effect of wind and mountains, some areas in China experience PM 2.5 pollution accumulation during spring and winter. We need to be vigilant because these areas with high PM 2.5 concentrations typically occur near cities., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Aerosol optical depth (AOD) has been widely used to estimate the near-surface PM 2.5 (fine particulate matter with particle size less than 2.5 μm). However, the total-column AOD obtained by passive remote sensing instruments can neither distinguish the contribution of AOD in various altitude layers nor obtain the vertical PM 2.5 concentration. In this study, we compared several AOD-PM 2.5 models including Extra Trees (ET), Random Forest (RF), Deep Neural Network (DNN), and Gradient Boosting Regression Tree (GBRT), and analyzed the corresponding results using AOD of different altitudes and auxiliary data from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). The results indicate that the ET model performs best in terms of the model effectiveness and feature interpretation on the training dataset. We conclude that the feature importance of the bottom layer AOD is higher than that of the upper and total column AOD. The results showed that regional differences existed in the optimal height of the AOD-PM 2.5 correlation in study area. The results of cross-validation indicate that ET manages the most appealing overall performance with an R 2 (RMSE) of 0.85 (17.77 μg/m 3 ). Regarding the 729 sites involved in this study, 73% had R 2  > 0.7, and the region or season with higher AOD feature importance achieves better model performance. The results of the AOD-PM 2.5 model in each layer were corrected using the AOD weight, to obtained the PM 2.5 vertical concentrations from 2015 to 2019. The results highlight that the high PM 2.5 concentration area is primarily near the ground and decreases with height. Additionally, the PM 2.5 vertical concentration in Beijing-Tianjin-Hebei (-1.80 μg/m 3 , P < 0.001), Central China (-1.62 μg/m 3 , P < 0.001), and Pearl River Delta (-0.66 μg/m 3 , P < 0.001) show an apparent downward trend. We believe that the vertical distribution analysis of PM 2.5 can provide meaningful information for studying air pollution., 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 © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)