Impact of stapler versus manual closure techniques on pharyngocutaneous fistula development post-total laryngectomy: A systematic review and meta-analysis.

Pharyngocutaneous fistula (PCF) is a major complication after total laryngectomy, with significant morbidity and mortality. Whether mechanical stapler closure of the pharynx reduces fistula rates compared to hand-sewn techniques remains unclear. We conducted an updated systematic review and meta-analysis to clarify this question. Five databases were systematically searched from inception through November 2023 for studies comparing stapler versus suture closure for fistula outcomes after laryngectomy. Odds ratios (OR) were pooled using random-effects models and fixed-effects models. Subgroup and sensitivity analyses were performed. Risk of bias was appraised using NHLBI tools. Nine studies with 803 patients were included. Mechanical closure significantly reduced fistula incidence versus suture closure (OR = 0.57, 95% CI 0.34-0.95, p = 0.03). Subgroup analysis found that stapling's protective effect varied by patient age, country/region, linear stapler size and female percentage. Stapling reduced fistula odds by 80% in the Turkey subgroup (OR = 0.20, 95% CI 0.09-0.50) but showed no benefit in other regions. Patients <60 years showed an 84% fistula reduction with stapling (OR = 0.17, 95% CI 0.06-0.45), whereas older subgroups did not. Linear stapler size of 60 mm significantly reduced fistula occurrence while 75 mm did not. There was no evidence that low female percentage mitigated stapling benefits. Mechanical stapler closure after total laryngectomy meaningfully reduces the likelihood of postoperative PCF formation compared to hand-sewn closure, especially for patients younger than 60 years old. The absolute risk reduction supports its utility to prevent this complication.

Unlocking the potential of LSTM for accurate salary prediction with MLE, Jeffreys prior, and advanced risk functions.

This article aims to address the challenge of predicting the salaries of college graduates, a subject of significant practical value in the fields of human resources and career planning. Traditional prediction models often overlook diverse influencing factors and complex data distributions, limiting the accuracy and reliability of their predictions. Against this backdrop, we propose a novel prediction model that integrates maximum likelihood estimation (MLE), Jeffreys priors, Kullback-Leibler risk function, and Gaussian mixture models to optimize LSTM models in deep learning. Compared to existing research, our approach has multiple innovations: First, we successfully improve the model's predictive accuracy through the use of MLE. Second, we reduce the model's complexity and enhance its interpretability by applying Jeffreys priors. Lastly, we employ the Kullback-Leibler risk function for model selection and optimization, while the Gaussian mixture models further refine the capture of complex characteristics of salary distribution. To validate the effectiveness and robustness of our model, we conducted experiments on two different datasets. The results show significant improvements in prediction accuracy, model complexity, and risk performance. This study not only provides an efficient and reliable tool for predicting the salaries of college graduates but also offers robust theoretical and empirical foundations for future research in this field.

Prediction of successful weaning from renal replacement therapy in critically ill patients based on machine learning.

BACKGROUND: Predicting the successful weaning of acute kidney injury (AKI) patients from renal replacement therapy (RRT) has emerged as a research focus, and we successfully built predictive models for RRT withdrawal in patients with severe AKI by machine learning. METHODS: This retrospective single-center study utilized data from our general intensive care unit (ICU) Database, focusing on patients diagnosed with severe AKI who underwent RRT. We evaluated RRT weaning success based on patients being free of RRT in the subsequent week and their overall survival. Multiple logistic regression (MLR) and machine learning algorithms were adopted to construct the prediction models. RESULTS: A total of 976 patients were included, with 349 patients successfully weaned off RRT. Longer RRT duration (7.0 vs. 9.6 d, p = 0.002, OR = 0.94), higher serum cystatin C levels (1.2 vs. 3.2 mg/L, p < 0.001, OR = 0.46), and the presence of septic shock (28.1% vs. 41.5%, p < 0.001, OR = 0.63) were associated with reduced likelihood of RRT weaning. Conversely, a positive furosemide stress test (FST) (60.2% vs. 40.7%, p < 0.001, OR = 2.75) and higher total urine volume 3 d before RRT withdrawal (755 vs. 125 mL/d, p < 0.001, OR = 2.12) were associated with an increased likelihood of successful weaning from RRT. Next, we demonstrated that machine learning models, especially Random Forest and XGBoost, achieving an AUROC of 0.95. The XGBoost model exhibited superior accuracy, yielding an AUROC of 0.849. CONCLUSION: High-risk factors for unsuccessful RRT weaning in severe AKI patients include prolonged RRT duration. Machine learning prediction models, when compared to models based on multivariate logistic regression using these indicators, offer distinct advantages in predictive accuracy.

Computational design of ultra-robust strain sensors for soft robot perception and autonomy.

Compliant strain sensors are crucial for soft robots' perception and autonomy. However, their deformable bodies and dynamic actuation pose challenges in predictive sensor manufacturing and long-term robustness. This necessitates accurate sensor modelling and well-controlled sensor structural changes under strain. Here, we present a computational sensor design featuring a programmed crack array within micro-crumples strategy. By controlling the user-defined structure, the sensing performance becomes highly tunable and can be accurately modelled by physical models. Moreover, they maintain robust responsiveness under various demanding conditions including noise interruptions (50% strain), intermittent cyclic loadings (100,000 cycles), and dynamic frequencies (0-23 Hz), satisfying soft robots of diverse scaling from macro to micro. Finally, machine intelligence is applied to a sensor-integrated origami robot, enabling robotic trajectory prediction (<4% error) and topographical altitude awareness (<10% error). This strategy holds promise for advancing soft robotic capabilities in exploration, rescue operations, and swarming behaviors in complex environments.

A Chinese verb semantic feature dataset (CVFD).

Language is an advanced cognitive function of humans, and verbs play a crucial role in language. To understand how the human brain represents verbs, it is critical to analyze what knowledge humans have about verbs. Thus, several verb feature datasets have been developed in different languages such as English, Spanish, and German. However, there is still a lack of a dataset of Chinese verbs. In this study, we developed a semantic feature dataset of 1140 Chinese Mandarin verbs (CVFD) with 11 dimensions including verb familiarity, agentive subject, patient, action effector, perceptual modality, instrumentality, emotional valence, action imageability, action complexity, action intensity, and the usage scenario of action. We calculated the semantic features of each verb and the correlation between dimensions. We also compared the difference between action, mental, and other verbs and gave some examples about how to use CVFD to classify verbs according to different dimensions. Finally, we discussed the potential applications of CVFD in the fields of neuroscience, psycholinguistics, cultural differences, and artificial intelligence. All the data can be found at https://osf.io/pv29z/ .

Mediation role of anxiety on social support and depression among diabetic patients in elderly caring social organizations in China during COVID-19 pandemic: a cross-sectional study.

BACKGROUND: Diabetes has become a prominent global public health problem, which is an important cause of death, disease burden, and medical and health economic burden. Previous studies have reported that majority of persons diagnosed with diabetes later presented with psychological and mental health diseases. The study aimed to explore the mediation role of anxiety on social support and depression among diabetic patents in elderly caring social organizations (SOs). METHODS: A multi-stage stratified cluster random sampling method was used in this cross-sectional study, and a questionnaire consisting of demographic questionnaire, MSPSS, GAD-7, and CES-D-10 was utilized to gather data. SPSS 22.0 and MPLUS 7.4 were used for statistical analysis. Spearman correlation analysis was employed to investigate correlations of key variables. A generalized linear model was used to exam factors associated with depression. Finally, the mediation effect among study variables was investigated by structural equation modeling (SEM). RESULTS: The average scores of social support, anxiety, and depression were 58.41 ± 14.67, 2.95 ± 3.95, and 7.24 ± 5.53, respectively. The factors of gender, social support, and anxiety were identified as significantly influential factors related to depression among diabetic patients in elderly caring SOs. The effect of social support on depression was significantly mediated by anxiety (ß = -0.467, 95%CI: -0.813 to -0.251). Furthermore, anxiety partially mediated the relationship between family support and depression (ß = -0.112, 95%CI: -0.229 to -0.012), and anxiety functioned as a complete mediator in the effect of significant others' support and depression (ß = -0.135, 95%CI: -0.282 to -0.024). CONCLUSIONS: The indirect effect of social support on depression through anxiety among diabetic patients in elderly caring SOs was elucidated. Social support played a key role in maintaining and regulating their mental health, particularly from family and significant others. Social support provided by both family and significant others exerted an important influence on maintaining and regulating their mental health. In light of this pathway, the elderly caring SOs should enhance the magnitude of social support from these two sources, thereby diminishing the likelihood of experiencing anxiety and depression.

Characteristics of atmospheric black carbon and its wet scavenging in Nanning, South China.

Based on in-situ measurement of black carbon (BC) and carbon monoxide (CO), the characteristics of BC emissions and wet scavenging were comprehensively investigated in Nanning, South China. The average annual BC concentration was 1.02 ± 0.53 µg m-3 with higher pollution levels during winter. In winter, a higher net BC/CO (ΔBC/ΔCO) ratio of 3.3 ± 0.3 ng m-3 ppb-1 along with an increased absorption Ångström exponent (AAE) and BC mass from biomass burning (BCbb), indicated a significant contribution of biomass burning to BC emissions. However, emissions from the traffic sector consistently exerted a dominant influence throughout the year. Cluster analysis of backward trajectories identified three types of air masses with distinct origins. Cluster #1 originated from Guangxi province and its vicinity, intermittently influencing the sampling site throughout the year with varying effects between winter and summer. This air mass brought in clean sea breeze in summer whereas transported a higher proportion of BCbb to the site during wintertime due to local open biomass burning. Cluster #3 primarily arrived in autumn and winter (October-December) from polluted central China, resulting in substantially high BC mass at the site. Cluster #2 coincided with the period (January-March) when extensive surface open biomass burning events occurred in Southeast Asia (SEA) regions. These BC aerosols in cluster#2 initially rose to higher altitudes above SEA before being regionally transported, but were significantly scavenged by clouds and precipitation during vertical uplift. The remaining BC exhibited a notably lower BC loss rate on relative humidity (RH) of -0.01 ng m-3 ppb-1 %-1 compared to cluster #1 (-0.03) and cluster #3 (-0.06), corresponding to an average BC transport efficiency of 0.85, 0.73, and 0.53, respectively. Nonetheless, air masses in cluster #2 could still transport considerably high BC mass to Nanning due to dry conditions and less wet scavenging along trajectory pathways. These findings provide valuable insights for policymakers and government officials in regulating and mitigating BC pollution in South China.

Pentraxins in invertebrates and vertebrates: From structure, function and evolution to clinical applications.

The immune system is divided into two broad categories, consisting of innate and adaptive immunity. As recognition and effector factors of innate immunity and regulators of adaptive immune responses, lectins are considered to be important defense chemicals against microbial pathogens, cell trafficking, immune regulation, and prevention of autoimmunity. Pentraxins, important members of animal lectins, play a significant role in protecting the body from pathogen infection and regulating inflammatory reactions. They can recognize and bind to a variety of ligands, including carbohydrates, lipids, proteins, nucleic acids and their complexes, and protect the host from pathogen invasion by activating the complement cascade and Fcγ receptor pathways. Based on the primary structure of the subunit, pentraxins are divided into short and long pentraxins. The short pentraxins are comprised of C-reactive protein (CRP) and serum amyloid P (SAP), and the most important member of the long pentraxins is pentraxin 3 (PTX3). The CRP and SAP exist in both vertebrates and invertebrates, while the PTX3 may be present only in vertebrates. The major ligands and functions of CRP, SAP and PTX3 and three activation pathways involved in the complement system are summarized in this review. Their different characteristics in various animals including humans, and their evolutionary trees are analyzed. The clinical applications of CRP, SAP and PTX3 in human are reviewed. Some questions that remain to be understood are also highlighted.

A Novel Passive Back-Support Exoskeleton With a Spring-Cable-Differential for Lifting Assistance.

Lower back injuries are the most common work-related musculoskeletal disorders. As a wearable device, a back-support exoskeleton (BSE) can reduce the risk of lower back injuries and passive BSEs can achieve a low device weight. However, with current passive BSEs, there is a problem that the user must push against the device when lifting the leg to walk, which is perceived as particularly uncomfortable due to the resistance. To solve this problem, we propose a novel passive BSE that can automatically distinguish between lifting and walking. A unique spring-cable-differential acts as a torque generator to drive both hip joints, providing adequate assistive torque during lifting and low resistance during walking. The optimization of parameters can accommodate the asymmetry of human gait. In addition, the assistive torque on both sides of the user is always the same to ensure the balance of forces. By using a cable to transmit the spring force, we placed the torque generator on the person's back to reduce the weight on the legs. To test the effectiveness of the device, we performed a series of simulated lifting tasks and walking trials. When lifting a load of 10 kg in a squatting and stooping position, the device was able to reduce the activation of the erector spinae muscles by up to 41%. No significant change in the activation of the leg and back muscles was detected during walking.

The DEAD-box RNA helicase ZmRH48 is required for the splicing of multiple mitochondrial introns, mitochondrial complex biosynthesis, and seed development in maize.

RNA helicases participate in nearly all aspects of RNA metabolism by rearranging RNAs or RNA-protein complexes in an adenosine triphosphate-dependent manner. Due to the large RNA helicase families in plants, the precise roles of many RNA helicases in plant physiology and development remain to be clarified. Here, we show that mutations in maize (Zea mays) DEAD-box RNA helicase 48 (ZmRH48) impair the splicing of mitochondrial introns, mitochondrial complex biosynthesis, and seed development. Loss of ZmRH48 function severely arrested embryogenesis and endosperm development, leading to defective kernel formation. ZmRH48 is targeted to mitochondria, where its deficiency dramatically reduced the splicing efficiency of five cis-introns (nad5 intron 1; nad7 introns 1, 2, and 3; and ccmFc intron 1) and one trans-intron (nad2 intron 2), leading to lower levels of mitochondrial complexes I and III. ZmRH48 interacts with two unique pentatricopeptide repeat (PPR) proteins, PPR-SMR1 and SPR2, which are required for the splicing of over half of all mitochondrial introns. PPR-SMR1 interacts with SPR2, and both proteins interact with P-type PPR proteins and Zm-mCSF1 to facilitate intron splicing. These results suggest that ZmRH48 is likely a component of a splicing complex and is critical for mitochondrial complex biosynthesis and seed development.

Factors related to the internal social capital of elderly-caring social organizations: a cross-sectional study in Chongqing, China.

BACKGROUND: Aging has given birth to the demand for high-quality elderly care service and social organizations (ESOs) are gradually taking on a supportive role in the field of elderly care services.. In view of this, our study is designed to examine influencing factors of social capital within the elderly-caring social organizations. METHOD: The study was conducted in four districts of Chongqing Province and a multi-stage random sampling method was used to sample 80 ESOs as subjects for the research. Through a meticulously crafted questionnaire, we gathered valuable data on internal social capital, basic information about the organization, and other variables. Univariate and Binary Logistic Regression analysis were performed on the data to explore the factors associated with social capital within the elderly-caring social organizations using IBM SPSS version 26.0. RESULT: The results showed that 67(83.8%) OF ESOs surveyed were A-type institutions and 13(16.3%) B-type institutions. Among them, 49(61.3%) institutions covered an area of more than 50m2.The institutions of ≤ 2 years were 33(41.3%), 21(26.3%) were established for ≤ 3 ≤ 8 years, and residual 26(32.5%) were institutions ˃ 8 years old. ESOs that possessed 4-6 management employees were 52.422 times more likely to score high for social support (p<0.05, OR = 52.422). Accommodating special care objects and hiring 16-30 employees were significantly linked to the shared language and shared vision dimension (p<0.001, OR = 0.8) and (p<0.05, OR = 8.672), respectively. and the overall social capital dimension (p<0.01, OR = 0.221) (p<0.05, OR = 5.730). CONCLUSION: ESOs with different basic conditions have different amounts of social capital. Factors such as the presence of special care and volunteer staff, a certain number of full-time staff as well as types of services rendered are accompanied with the higher internal social capital of ESOs.

The satisfaction of elderly people with elderly caring social organizations and its relationship with social support and anxiety during the COVID-19 pandemic: a cross-sectional study.

BACKGROUND: With the deepening of China's aging population, higher demands have been placed on the supply of elderly care services. As one of the main sources of providing elderly care services, the quality of service provided by elderly caring social organizations (SOs) directly affects the quality of life of the elderly. In recent years, mental health issues among the elderly have become increasingly prominent, especially with the onset of the COVID-19 pandemic. Necessitating the need to pay much more attention to the social support and mental health of this population. This study, therefore, explores the mediating role of institutional satisfaction between the social support and anxiety levels of elderly people in Chongqing's elderly caring SOs. METHOD: This study employed a multi-stage stratified random sampling method to survey 1004 service recipients in elderly caring social organizations from July to August 2022. The self-made sociodemographic questionnaire, institutional satisfaction questionnaire, MSPSS, and GAD-7 were used to collect data on sociodemographic characteristics, institutional satisfaction, social support, and anxiety levels of older adults. Exploratory Factor Analysis and Cronbach's alpha were used to test construct validity and scale reliability, respectively. Data features were described with One-Way Analysis of Variance, while Multiple Linear Regression and Structural Equation Modeling were used to evaluate relationships between social support, institutional satisfaction, and anxiety levels. RESULTS: The average institutional satisfaction score for elderly people in elderly caring SOs was 48.14 ± 6.75. Specifically, the satisfaction score for environmental quality and the satisfaction score for service quality were 16.63 ± 2.56 and 31.52 ± 4.76, respectively. In terms of socio-demographic variables, the presence of visits from relatives, personal annual average income, and self-rated health status all have significant effects on anxiety. Elders who receive visits from relatives have lower levels of anxiety compared to those who do not. Personal annual average income and self-rated health status are negatively correlated with anxiety levels. Social support had significant positive effect on institutional satisfaction, while institutional satisfaction had significant negative effect on anxiety. Institutional satisfaction partially mediated the relationship between social support and anxiety. CONCLUSIONS: Our research demonstrates that improving the quality of organizational services in elderly caring SOs and increasing institutional satisfaction among the elders has significant potential for reducing anxiety levels among the elderly. Additionally, the social support by visits from family members cannot be overlooked. We encourage increasing the frequency of family visits through various means to enhance the support provided to elderly individuals.

Ceftazidime/Avibactam for the Treatment of Carbapenem-Resistant Pseudomonas aeruginosa Infection in Lung Transplant Recipients.

Background: Experience of ceftazidime-avibactam (CAZ/AVI) for carbapenem-resistant Pseudomonas aeruginosa (CRPA) infection in recipients after lung transplantation (LT) is relatively limited. Methods: A retrospective observational study was conducted on lung transplant recipients receiving CAZ/AVI therapy for CRPA infection. The primary outcomes were the 14-day and 30-day mortality. The secondary outcomes were clinical cure and microbiological cure. Results: Among 183 LT recipients, a total of 15 recipients with CRPA infection who received CAZ/AVI therapy were enrolled in this study. The mean age of recipients was 54 years and 73.3% of recipients were male. The median time from infection onset to initiation of CAZ/AVI treatment was 4 days (IQR, 3-7) and the mean duration of CAZ/AVI therapy was 10 days. CAZ/AVI was mainly administered as monotherapy in LT recipients (80%). Among these eligible recipients, 14-day and 30-day mortality were 6.7% and 13.3%, respectively. The clinical cure and microbiological cure rates of CAZ/AVI therapy were 53.3% and 60%, respectively. Three recipients (20%) experienced recurrent infection. In addition, the mean lengths of ICU stay and hospital stay were 24 days and 35 days, respectively, among LT recipients. Conclusion: CAZ/AVI may be an alternative and promising regimen for CRPA eradiation in lung transplant recipients.

Glutamine Induced High-Quality Perovskite Film to Improve the Efficiency of NIR Perovskite Light-Emitting Diodes.

Formamidine lead iodide (FAPbI3 ) is an important material for realizing high-performance near-infrared light-emitting diodes (NIR-LEDs). However, due to the uncontrollable growth of solution-processed films which usually causes low coverage, and poor surface morphology, the development of FAPbI3 -based NIR-LEDs is hindered, restraining its potential industrial applications. In this work, by employing glutamine (Gln) in perovskite precursor, the quality of FAPbI3 film is improved significantly. Due to the ameliorated solution process by the organic additive, the film coverage over the substrate is substantially enhanced. Meanwhile, the trap state of grain is largely reduced. Consequently, NIR perovskite LEDs are demonstrated with a maximum external quantum efficiency (EQE) of 15% with the emission peak at 795 nm, which is four times higher than the device with pristine perovskite film.

Contrasting Near-Surface Ozone Pollution in Wet and Dry Year over China.

The near-surface ozone concentration was evaluated in two typical years with contrasting climatic impacts over the China region induced by El Niño-Southern Oscillation, which had either dry conditions (drought) with intense solar radiation and higher temperatures or wet conditions with opposite meteorological conditions. Surface ozone was observed to aggravate notably by 30% over Northern China in summer and by 50% over Eastern China in autumn in the dry year compared to the wet year. The ozone aggravation was found to be mainly ascribed to the reduced precipitation (relative humidity), enhanced solar radiation and increased temperature rather than primary emission (indicated by carbon monoxide). The health impacts showed the mortality attributable to ozone sharply increased by ~55% in Guangdong while the number of cases dying from ozone-related respiratory diseases per 100,000 population at risk was elevated by ~41% and ~17% for Guangdong (in the Pearl River Delta) and Jiangsu (in the Yangtze River Delta) province (two regions that have been reported to be highly influenced by surface ozone in China), respectively, in the dry year relative to the wet year, indicative of the significant adverse health effects of ozone aggravation. These results highlight the essential contribution of climate anomalies to surface ozone pollution. Efforts to suppress ozone aggravation can be beneficial to public health if extreme drought is predicted, and reasonable policy is implemented.

A novel passive shoulder exoskeleton for assisting overhead work.

Shoulder exoskeletons (SEs) can assist the shoulder joint of workers during overhead work and are usually passive for good portability. However, current passive SEs face the challenge that their torque generators are often attached to the human arm, which adds a significant amount of weight to the user's arms, resulting in additional energy consumption of the user. In this paper, we present a novel passive SE whose torque generator is attached to the user's back and assists the shoulder joint through Bowden cables. Our approach greatly reduces the weight on the user's arms and can accommodate complex shoulder joint movements with simple and lightweight mechanical structure based on Bowden cables. In addition, to match the nonlinear torque requirements of the shoulder joint, a unique spring-cam mechanism is proposed as the torque generator. To verify the effectiveness of the device, we conducted a usability test based on muscle activations of 10 healthy subjects. When assisting overhead work, the SE significantly reduced the mean and maximum electromyography signals of the shoulder-related muscles by up to 25%. The proposed SE contributes to further research on passive SE design to improve usability, especially in terms of reducing weight on human arms.

Clinical Application of Submental Island Flaps in Repair and Reconstruction of Head and Neck Tumors: Retrospective Review of a Single-Center Experience.

BACKGROUND: Based on our cadaveric study findings and the clinical practice, the improved submental island flaps (SIF) used on a case series to reconstruct postoperative defects were reviewed and analyzed, to summarize the technical operation of flap cutting and propose the anterograde anatomical technique of point-line-plane alignment. METHODS: The cadaveric study was carried out first and a case series of about 23 head and neck tumor cases that underwent one-stage SIF repair were reviewed and followed up. The intraoperative anatomy, the technical essentials for vascular pedicle protection and submandibular lymph nodes treatment, and the rational design of flap incisions were analyzed and described. RESULTS: Most patients (21/23, 91.3%), comprising 19 males and 4 females with a mean age of 59 years, recovered completely from the application of SIFs in the repair and reconstruction of head and neck tumors; Only 2 patients experienced partial flap necrosis, which resolved following a local dressing change. The predominant donor site complication was transitory paralysis of the mandibular marginal branch of the facial nerve (MMBFN) (3/23, 13.0%), and the donor site was closed in one stage without skin grafting. The hair growth on skin flaps was not an issue for male patients requiring postoperative radiotherapy. CONCLUSIONS: SIF is a viable choice for correcting abnormalities of the head and neck tumor with the convenience of flap cutting and the effectiveness of the repair. In addition, it permits simultaneous treatment of the lymph nodes in the region I.

[Investigating the Pollutants of Marine Shipping Emissions Along the East China Sea by Combining in-situ Measurements and Automatic Identification System].

Marine shipping emissions have important impacts on air quality and climate. This type of anthropogenic emission remains largely unclear due to complex vessel types and activities. A coastal site near the Ningbo-Zhoushan port along the East China Sea was selected for this study, representing one of the hotspot regions globally with the most intensive shipping activities, in combination with vessels for both domestic and international transportation. Long-term temporal variations in key gaseous and particulate pollutants were obtained at the site using in-situ measurements, and the vessel speed associated with each classified vessel type was obtained according to the automatic identification system (AIS). In combination of backward trajectories, we were able to identify the periods predominated by the surrounding vessel emissions (in warm seasons, dominated by vessels in full operation or idle mode) or influenced by continental outflow (in cold season). We found that emissions of sulphur dioxide (SO2), nitrogen oxides (NOx), and black carbon (BC) aerosol were highly correlated with high-speed vessels, whereas carbon monoxide (CO) was likely related to lower operation speed. The total particulate matter (PM) was not directly linked to vessel activities. The enhancement factor in operation mode compared to that in idle mode was approximately 1-4 for most pollutants. This direct ambient observation of the emissions from a range of mixed vessel types may provide a basis for evaluating the shipping emission inventory.

Evaluation of the CAMS reanalysis for atmospheric black carbon and carbon monoxide over the north China plain.

Black carbon (BC) and carbon monoxide (CO) at different model levels from the Copernicus Atmosphere Monitoring Service (CAMS) reanalysis were comprehensively evaluated against observations performed simultaneously on both surface and mountain sites in winter and summer in the North China Plain for the first time. CAMS could capture the seasonal difference in BC and CO emission on both sites but showed significant and persistent biases. Biases were high on the surface site and low on the mountain site for both seasons, implying the uncertainties in emission inventories used in the CAMS reanalysis which may have more influence near source. Biases were reduced and the correlation coefficient of CAMS BC with observed BC increased when two datasets were compared on a daily basis, which suggests daily or longer time averaged CAMS BC could be more suitable for trend analysis. Although CAMS could generally reproduce the distinct diurnal variation of BC and CO on both sites, the inaccurate representation of the daily evolution of planetary boundary layer (PBL) in model may bring more uncertainties to the concentration biases on surface from midnight to early morning. BC hydrophilic ratio from CAMS displayed large biases compared to observations with no seasonal difference on both sites, which was probably resulted from the initial emission state of BC hygroscopicity for all source types in model. Uncertainties in the removal processes and the simplified aging processes in model could further induce uncertainty in modelling BC hydrophilic ratio in the CAMS. These results could not only be referenced for the improvement on CAMS reanalysis but also facilitate model or trend analysis of BC and CO pollution by utilizing the CAMS reanalysis product from both short- and long-term perspectives, which will be beneficial to both the mitigation and policy-making on primary emissions in China.