Early-Career Researchers in China during the Pandemic: Qualitative Evidence from a Longitudinal Study

The outbreak of COVID-19 has changed the world in many aspects, and global scientific research has also been challenged. Early-career researchers (ECRs) who just start academic careers are prominently affected by the pandemic. To explore how Chinese ECRs have been affected, longitudinal qualitative interviews were conducted with twenty-four Chinese ECRs from different disciplines and universities in 2020 and 2021. As the results show, Chinese ECRs worry that their future prospects are limited by increased workloads and reduced productivity. However, the new wave of change did not occur for them, and their work resumed its routine and was relatively stable. Over two years, Chinese ECRs got used to working from home and giving online courses, but they were increasingly confused about when the pandemic will end. What bothers ECRs most is the inefficiency of communication and collaboration due to the travel bans, although they became familiar with the online way. © University of Toronto Press, 2023.

Real human close contact-based analysis on COVID-19 combined interventions

COVID-19 has threatened human lives. However, the efficiency of combined interventions on COVID-19 has not been accurately analyzed. In this study, an improved SEIR model considering both real human indoor close contact behaviors and personal susceptibility to COVID-19 was established. Taking Hong Kong as an example, a quantitative efficiency assessment of combined interventions (i.e. close contact reduction, vaccination, mask-wearing, school closures, workplace closures, and body temperature screening in public places) was carried out. The results showed that the infection risk of COVID-19 of students, workers, and non-workers/students were 3.1%, 8.7%, and 13.6%, respectively. The basic reproduction number R0 was equal to 1 when the close contact reduction rate was 59.9% or the vaccination rate reached 89.5%. The results could provide scientific support for interventions on COVID-19 prevention and control. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

Proteomics research of SARS-CoV-2 and COVID-19 disease

Currently, coronavirus disease 2019 (COVID-19) is still spreading in a global scale, exerting a massive health and socioeconomic crisis. Deep insights into the molecular functions of the viral proteins and the pathogenesis of this infectious disease are urgently needed. In this review, we comprehensively describe the proteome of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and summarize their protein interaction map with host cells. In the protein interaction network between the virus and the host, a total of 787 host prey proteins that appeared in at least two studies or were verified by co-immunoprecipitation experiments. Together with 29 viral proteins, a network of 1762 proximal interactions were observed. We also review the proteomics results of COVID-19 patients and proved that SARS-CoV-2 hijacked the host's translation system, post-translation modification system, and energy supply system via viral proteins, resulting in various immune disorders, multiple cardiomyopathies, and cholesterol metabolism diseases. © 2022 the author(s), published by De Gruyter, Berlin/Boston.

Aerosol Transmission and Control of SARS-CoV-2

One fundamental question about any novel pathogen is: how does it transmit? Answering this question will help to protect ourselves from the agent, at least until effective vaccines and antiviral therapies can be developed, especially if it is an agent of moderate to high lethality. Initially, at the start of the Coronavirus disease 2019 (COVID-19) pandemic, more emphasis was placed on handwashing rather than on droplet and aerosol transmission. Although severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2)-infected secretions such as saliva can spread the virus to hands, it became increasing evident that the virus mostly transmitted through close contact (though not necessarily touching), whilst people were breathing, talking, laughing, singing, coughing and sneezing near one another. During such respiratory activities, droplets and aerosols are produced together, and the amount of transmission due to these differentsized liquid particles will likely vary between individuals at different stages of their infection and illness. This question became even more complex as it emerged that viral transmission can occur for several days before symptom onset, and that asymptomatic cases can also shed just as much virus and potentially transmit it just as well as symptomatic cases. This chapter summarizes our understanding of how SARS-CoV-2 transmits and the infection control precautions to reduce this. © 2023 by World Scientific Publishing Co. Pte. Ltd.

Influencing factors and clinical significance of liver function damage in patients diagnosed with COVID-19.

Objective: To invetigate the influencing factors and clinical significance of liver function damage (LFD) in patients diagnosed with Corona Virus Disease 2019 (COVID-19). Method(s): The retrospective case-control study was conducted. The clinicopathological data of 51 patients with COVID-19 who were admitted to the Sino-French New City Branch of Tongji Hospital Affiliated to Huazhong University of Science and Technology by the 5th group assisting team from the First Hospital of Jilin University from February 9th to 27th in 2020 were collected. There were 27 males and 24 females, aged from 36 to 86 years, with an average age of 68 years. The treatment modality was according to the diagnostic and therapeutic guideline for COVID-19 (Trial 6th edition) issued by National Health Commission. Observation indicators: (1) clinical data of patients;(2) analysis of liver function index and treatment of LFD;(3) analysis of influencing factors for LFD. Measurement data with normal distribution were represented as Mean+/-SD, and measurement data with skewed distribution were described as M (range). Count data were described as absolute numbers or percentages, and comparison between groups was analyzed using the chi-square test. The Logistic regression method was used for univariate analysis. Result(s): (1) Clinical data of patients: of the 51 patients, 21 were classified as ordinary type of COVID-19, 19 as severe type and 11 as critical type. In terms of medical history, 31 patients suffered from more than or equal to one kind of chronic disease, 20 had no history of chronic disease. Thirteen patients had the drinking history and 38 had no drinking history. Seven patients were hepatitis positive and 44 were hepatitis negative. Five patients had septic shock at admission, 5 had systemic inflammatory response syndrome (SIRS), and 41 had neither shock nor SIRS. The body mass index (BMI), time from onset to admission, temperature, heart rate, respiratory rate of the 51 patients were (24+/-3)kg/m2, (13+/-5)days, 36.5 (range, 36.0-38.1 ), 82 times/minutes (range, 50-133 times/minutes), 20 times/minutes (range, 12-40 times/minutes). The white blood cell count, level of creatinine, and level of b-type natriuretic peptide within 24 hours after admission were 6.3x109/L [range, (2.2-21.7)x109/L], 75 mumol/L (range, 44-342 mumol/L), 214 ng/L (range, 5-32 407 ng/L). (2) Analysis of liver function index and treatment of LFD: the level of alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), direct bilirubin (DBil), indirect bilirubin (IBil), activated partial thromboplastin time (APTT) and prothrombin time (PT) were 31 U/L (range, 7-421 U/L), 29 U/L (range, 15-783 U/L), 36 U/L (range, 13-936 U/L), 76 U/L (range, 41-321 U/L), 4.9 mumol/L (range, 2.6-14.3 mumol/L), 5.8 mumol/L (range, 2.6-23.9 mumol/L), 37.2 s (range, 30.9-77.1 s), 13.9 s (range, 12.5-26.7 s), respectively. The percentages of cases with abnormal ALT, AST, GGT, ALP, DBil, IBil, APTT and PT were 47.1%(24/51), 47.1%(24/51), 35.3%(18/51), 13.7%(7/51), 7.8%(4/51), 2.0%(1/51), 21.6%(11/51), and 19.6%(10/51), respectively. Of the 51 patients, LFD was detected in 10 patients classified as ordinary type, in 9 patients as severe type, and in 10 as critical type, respectively. In the 51 patients, 1 of 22 patients with normal liver function developed respiratory failure and received mechanical ventilation within 24 hours after admission, while 9 of 29 patients with abnormal liver function developed respiratory failure and received mechanical ventilation, showing a significant difference between the two groups (chi2=5.57, P<0.05). (3) Analysis of influencing factors for LFD. Results of univariate analysis showed that clinical classification of COVID-19 as critical type was a related factor for LFD of patients (odds ratio=10.000, 95% confidence interval: 1.050-95.231, P<0.05). Conclusion(s): COVID-19 patients with LFD are more susceptible to develop respiratory failure. The clinical classification of COVID-19 as critic l type is a related factor for LFD of patients.Copyright © 2020 by the Chinese Medical Association.

CMC_v2: Towards More Accurate COVID-19 Detection with Discriminative Video Priors

This paper presents our solution for the 2nd COVID-19 Competition, occurring in the framework of the AIMIA Workshop at the European Conference on Computer Vision (ECCV 2022). In our approach, we employ the winning solution last year which uses a strong 3D Contrastive Mixup Classification network (CMC_v1) as the baseline method, composed of contrastive representation learning and mixup classification. In this paper, we propose CMC_v2 by introducing natural video priors to COVID-19 diagnosis. Specifically, we adapt a pre-trained (on video dataset) video transformer backbone to COVID-19 detection. Moreover, advanced training strategies, including hybrid mixup and cutmix, slice-level augmentation, and small resolution training are also utilized to boost the robustness and the generalization ability of the model. Among 14 participating teams, CMC_v2 ranked 1st in the 2nd COVID-19 Competition with an average Macro F1 Score of 89.11%. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Boosting COVID-19 Severity Detection with Infection-Aware Contrastive Mixup Classification

This paper presents our solution for the 2nd COVID-19 Severity Detection Competition. This task aims to distinguish the Mild, Moderate, Severe, and Critical grades in COVID-19 chest CT images. In our approach, we devise a novel infection-aware 3D Contrastive Mixup Classification network for severity grading. Specifically, we train two segmentation networks to first extract the lung region and then the inner lesion region. The lesion segmentation mask serves as complementary information for the original CT slices. To relieve the issue of imbalanced data distribution, we further improve the advanced Contrastive Mixup Classification network by weighted cross-entropy loss. On the COVID-19 severity detection leaderboard, our approach won the first place with a Macro F1 Score of 51.76%. It significantly outperforms the baseline method by over 11.46%. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Fund ESG performance and downside risk: Evidence from China

Whether responsible investing reduces portfolio risk remains open to discussion. We study the relationship between ESG performance and downside risk at fund level in the Chinese equity mutual fund market. We find that fund ESG performance is positively associated with fund downside risk during the period between July 2018 and March 2021, and that the positive relationship weakens during the COVID-19 pandemic. We propose three channels through which fund ESG performance could affect fund downside risk: (i) the firm channel in which the risk-mitigation effect of portfolio firms' good ESG practices could be manifested at fund level, (ii) the diversification channel in which the portfolio concentration of high ESG-rated funds could amplify fund downside risk, and (iii) the flow channel in which funds' better ESG performance may attract greater investor flows that could reduce fund downside risk. We show evidence that the observed time-varying relationship between fund ESG performance and downside risk is driven by the relative force of the three channels. © 2023 Elsevier Inc.

Bayesian Network Model of China's Financial Risk Under COVID-19 Based on Grey Clustering

The panic caused by COVID-19 and the stagnation of business activities induced the continuous breeding of China's financial risks. This paper considers the COVID-19 and economic indexes as nodes to establish the Bayesian topology of financial risk. The liquidity, sovereign, and stock market risks are mainly considered to evaluate the financial risk. Based on the risk characteristics, the central interval trapezoidal possibility functions are designed, then the grey clustering model is used to classify the financial risk into four different levels. The possibility distribution of financial risk levels under different COVID-19 index levels is inferenced through the Bayesian network. Finally, each node's monthly time series data from October 2019 to May 2021 is used to learn by NETICA software, and the conditional probability of each node and the possibility of financial risk are deduced. It is concluded that liquidity risk and sovereign risk are more sensitive to COVID-19, while the stock market risk is not very sensitive to it.

Effects of occupant behavior and ventilation on exposure to respiratory droplets in the indoor environment

To quantify the risk of the transmission of respiratory infections in indoor environments, we systematically assessed exposure to talking- and breathing-generated respiratory droplets in a generic indoor environment using computational fluid dynamic (CFD) simulations. The flow field in the indoor environment was obtained with SST k-ω model and Lagrangian method was used to predict droplet trajectories, where droplet evaporation was considered. Droplets can be categorized into small droplets (initial size ≤30 μm or ≤10 μm as droplet nuclei), medium droplets (30–80 μm) and large droplets (>100 μm) according to the exposure characteristics. Droplets up to 100 μm, particular the small ones, can contribute to both short-range and long-range airborne routes. For the face-to-face talking scenario, the intake fraction and deposition fractions of droplets on the face and facial mucosa of the susceptible were up to 4.96%, 2.14%, and 0.12%, respectively, indicating inhalation is the dominant route. The exposure risk from a talking infector decreases monotonically with the interpersonal distance, while that of nasal-breathing generated droplets maintains a relatively stable level within 1.0 m. Keeping an angle of 15° or above with the expiratory flow is efficient to reduce intake fractions to <0.37% for small droplets. Adjusting the orientation from face-to-face to face-to-back can reduce exposure to small droplets by approximately 88.0% during talking and 66.2% during breathing. A higher ventilation rate can reduce the risk of exposure to small droplets but may increase the risk of transmission via medium droplets by enhancing their evaporation rate. This study would serve as a fundamental research for epidemiologist, healthcare workers and the public in the purpose of infection control. © 2023 Elsevier Ltd

Conversational head movement decreases close-contact exposure to expired respiratory droplets

People constantly move their heads during conversation, as such movement is an important non-verbal mode of communication. Head movement alters the direction of people's expired air flow, therefore affecting their conversational partners' level of exposure. Nevertheless, there is a lack of understanding of the mechanism whereby head movement affects people's exposure. In this study, a dynamic meshing method in computational fluid dynamics was used to simulate the head movement of a human-shaped thermal manikin. Droplets were released during the oral expiration periods of the source manikin, during which it was either motionless, was shaking its head or was nodding its head, while the head of a face-to-face target manikin remained motionless. The results indicate that the target manikin had a high level of exposure to respiratory droplets when the source manikin was motionless, whereas the target manikin's level of exposure was significantly reduced when the source manikin was shaking or nodding its head. The source manikin had the highest level of self-exposure when it was nodding its head and the lowest level of self-exposure when its head was motionless. People's level of exposure during close contact is highly variable, highlighting the need for further investigations in more realistic conversational scenarios. Copyright © 2022 Elsevier B.V.

When Evil Calls: Targeted Adversarial Voice over IP Network

As the COVID-19 pandemic fundamentally reshaped the remote life and working styles, Voice over IP (VoIP) telephony and video conferencing have become a primary method of connecting communities together. However, little has been done to understand the feasibility and limitations of delivering adversarial voice samples via such communication channels. In this paper, we propose TAINT-Targeted Adversarial Voice over IP Network, the first targeted, query-efficient, hard label black-box, adversarial attack on commercial speech recognition platforms over VoIP. The unique channel characteristics of VoIP pose significant new challenges, such as signal degradation, random channel noise, frequency selectivity, etc. To address these challenges, we systematically analyze the structure and channel characteristics of VoIP through reverse engineering. A noise-resilient efficient gradient estimation method is then developed to ensure a steady and fast convergence of the adversarial sample generation process. We demonstrate our attack in both over-the-air and over-the-line settings on four commercial automatic speech recognition (ASR) systems over the five most popular VoIP Conferencing Software (VCS). We show that TAINT can achieve performance that is comparable to the existing methods even with the addition of VoIP channel. Even in the most challenging scenario where there is an active speaker in Zoom, TAINT can still succeed within 10 attempts while staying out of the speaker focus of the video conference. © 2022 Owner/Author.

No toxic reaction observed after 2-week repeated administration of recombinant whole human anti-SARS-CoV-2 monoclonal antibody 2811 injection in rhesus monkeys

OBJECTIVE To find out whether 2811 will cause toxic reactions in animals, and determine the safe dose of without any toxic reactions and the relationship between the dose, time of administration and results of the toxicity test. METHODS Thirty healthy rhesus monkeys were selected and randomly divided into 3 groups, 1 O in each group (half males and half females), namely, the solvent control group, 2811 100 and 400 mg* kg-1 groups, respectively. The solvent control group was iv given 0.9% sodium chloride injection, while the experimental groups were iv given 2811 100 and 400 mg* kg-1 , respectively, once every 6 days, 3 times in 2 weeks, and allowed to recover for 9 weeks after drug withdrawal. During the test, the body weight, food intakes, body temperatures, ophthalmology, blood pressure, electrocardiograms, blood routine, anticoagulation, blood biochemistry, electrolytes, urine, systemic anatomy, organ weight and coefficient were observed, while histopathology and immunology tests were performed. At the same time, the anti-drug antibody (ADA) and plasma concentrations were determined, and toxikinetic parameters were analyzed. RESULTS During the experiment, the observation of general symptoms, body mass, food intakes, body temperatures, ophthalmology, blood pressure, electrocardiograms, blood routine, anticoagulation, blood biochemistry, electrolytes, urine, organ weight and coefficient, histopathology and immunology of animals in each dose group showed no significant changes related to the tested animals. ADA was not detected in any of the groups. Plasma drug concentrations in 2B11 100 and 400 mg* kg-1 groups were basically consistent and proportional to the dose, so was the ratio of peak concentration and exposure. 2B11 injection showed linear kinetics in vivo. CONCLUSION Under the conditions set in this test, the 2-week repeated administration toxicity test of 2B11 in rhesus monkeys is safe, and no clinical adverse reactions are observed at the dose level of 400 mg*kg-1, which provides reference for the follow-up clinical study of 2B11. Copyright © 2022 Chinese Journal of Pharmacology and Toxicology. All rights reserved.

Analysis of the world oil and gas exploration situation in 2021

The global exploration investment, new oil and gas discoveries, exploration business adjustment strategies of oil companies in 2021, and future favorable exploration domains are systematically analyzed using commercial databases such as IHS and public information of oil companies. It has been found that the world oil and gas exploration situation in 2021 has continued the downturn since the outbreak of COVID-19. The investment and drilling workload decreased slightly, but the success rate of exploration wells, especially deepwater exploration wells, increased significantly, and the newly discovered reserves increased slightly compared with last year. Deep waters of the passive continental margin basins are still the leading sites for discovering conventional large and medium-sized oil and gas fields. The conventional oil and gas exploration in deep formations of onshore petroliferous basins has been keeping a good state, with tight/shale oil and gas discoveries made in Saudi Arabia, Russia, and other countries. While strengthening the exploration and development of local resources, national, international, and independent oil companies have been focusing on major overseas frontiers using their advantages, including risk exploration in deep waters and natural gas. Future favorable exploration directions in the three major frontiers, the global deep waters, deep onshore formations, and unconventional resources, have been clarified. Four suggestions are put forward for the global exploration business of Chinese oil companies: first, a farm in global deepwater frontier basins in advance through bidding at a low cost and adopt the “dual exploration model” after making large-scale discoveries;second, enter new blocks of emerging hot basins in the world through farm-in and other ways, to find large oil and gas fields quickly;third, cooperate with national oil companies of the resource host countries in the form of joint research and actively participate exploration of deep onshore formations of petroliferous basins;fourth, track tight/shale oil and gas cooperation opportunities in a few countries such as Saudi Arabia and Russia, and take advantage of mature domestic theories and technologies to farm in at an appropriate time. © 2022 Research Institute of Petroleum Exploration & Development, PetroChina

Using Deep Learning to Identify Linguistic Features that Facilitate or Inhibit the Propagation of Anti- and Pro-Vaccine Content on Social Media

Anti-vaccine content is rapidly propagated via social media, fostering vaccine hesitancy, while pro-vaccine content has not replicated the opponent's successes. Despite this dis-parity in the dissemination of anti- and pro-vaccine posts, linguistic features that facilitate or inhibit the propagation of vaccine-related content remain less known. Moreover, most prior machine-learning algorithms classified social-media posts into binary categories (e.g., misinformation or not) and have rarely tackled a higher-order classification task based on divergent perspectives about vaccines (e.g., anti-vaccine, pro-vaccine, and neutral). Our objectives are (1) to identify sets of linguistic features that facilitate and inhibit the propagation of vaccine-related content and (2) to compare whether anti-vaccine, pro-vaccine, and neutral tweets contain either set more frequently than the others. To achieve these goals, we collected a large set of social media posts (over 120 million tweets) between Nov. 15 and Dec. 15, 2021, coinciding with the Omicron variant surge. A two-stage framework was developed using a fine-tuned BERT classifier, demonstrating over 99 and 80 percent accuracy for binary and ternary classification. Finally, the Linguistic Inquiry Word Count text analysis tool was used to count linguistic features in each classified tweet. Our regression results show that anti-vaccine tweets are propagated (i.e., retweeted), while pro-vaccine tweets garner passive endorsements (i.e., favorited). Our results also yielded the two sets of linguistic features as facilitators and inhibitors of the propagation of vaccine-related tweets. Finally, our regression results show that anti-vaccine tweets tend to use the facilitators, while pro-vaccine counterparts employ the inhibitors. These findings and algorithms from this study will aid public health officials' efforts to counteract vaccine misinformation, thereby facilitating the delivery of preventive measures during pandemics and epidemics. © 2022 IEEE.

Visual Analysis of the National Characteristics of the COVID-19 Vaccine Based on Knowledge Graph

The aim is to construct a country-dimension knowledge graph of COVID-19 vaccines from the information of COVID-19 vaccines and to analyze the leading countries of vaccine R&D by combining the advantages of easy operation and intuitive feeling of knowledge graph visualization, to provide a reference for Chinese vaccine R&D departments and international cooperation. In this paper, through data collection, based on entity extraction and relationship construction, a knowledge graph of country dimensions was established by specifying the central vaccine R&D countries and vaccine distribution, and multidimensional microdata such as word frequency and betweenness centrality were combined to analyze the national characteristics of the COVID-19 vaccine. The analysis of the knowledge graph of the country dimension of the COVID-19 vaccine shows that countries with robust technology and economies, such as the US and China, choose to develop vaccine distribution independently, countries with advanced economies, such as Saudi Arabia, decide to purchase vaccine distribution, and less developed countries, such as South Africa and Latin America, need international aid for vaccines or purchase low-cost vaccines. This paper constructs the correlation between nodes and nodes of the COVID-19 vaccine with the help of a knowledge graph, systematically and comprehensively reveals the research mainstay and distribution model of the COVID-19 vaccine from the national level, and provides rationalized suggestions for international cooperation in vaccine R&D in China. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

The link between genetic variation and variability in vaccine responses: a narrative review

Vaccines are one of the biggest successes in modern history and are particularly important in light of the multiple ongoing epidemics. Recently, vaccines have protected peoples' health and lives around the world during the coronavirus disease 2019 pandemic. Different types of vaccines have their own characteristics and advantages and are used in the context of different epidemics. Responses to vaccination are also different, and can include adverse reactions and absent responses. These individual differences are thought to be influenced by host genes. In this review, we first discuss vaccine types and characteristics. Second, we discuss different responses to vaccination, primarily focusing on the association between genetic variation and inter-individual differences.

Risk perception, anxiety, and depression among hospital pharmacists during the COVID-19 pandemic: The mediating effect of positive and negative affect

This study investigated the impacts of risk perception of COVID-19 on anxiety and depression symptoms among hospital pharmacists in China. We conducted a cross-sectional study with hospital pharmacists during the COVID-19 pandemic in China. Some 4,219 hospital pharmacists completed an online survey including demographic questions, risk perception of COVID-19, General Anxiety Disorder-7, Patient Health Questionnaire-9, and Positive and Negative Affect Schedule. Multivariate regression and mediation analyses were conducted. The results indicated that 41.9% and 29.4% of hospital pharmacists experienced mild to severe levels of anxiety and depression symptoms, respectively. In older age, a higher level of risk perception of COVID-19, and negative affect experience were risk factors, whereas positive affect experience was a protective factor for anxiety and depression symptoms among pharmacists. Experience of positive and negative affect mediated the relationship between risk perception of COVID-19 and anxiety and depression among hospital pharmacists in China. Timely mental health services need to be provided for hospital pharmacists during the COVID-19 pandemic.

Evaluation of Long-Term Modeling Fine Particulate Matter and Ozone in China During 2013-2019

Air quality in China has been undergoing significant changes due to the implementation of extensive emission control measures since 2013. Many observational and modeling studies investigated the formation mechanisms of fine particulate matter (PM2.5) and ozone (O-3) pollution in the major regions of China. To improve understanding of the driving forces for the changes in PM2.5 and O-3 in China, a nationwide air quality modeling study was conducted from 2013 to 2019 using the Weather Research and Forecasting/Community Multiscale Air Quality (WRF/CMAQ) modeling system. In this study, the model predictions were evaluated using the observation data for the key pollutants including O-3, sulfur dioxide (SO2), nitrogen dioxide (NO2), and PM2.5 and its major components. The evaluation mainly focused on five major regions, that is , the North China Plain (NCP), the Yangtze River Delta (YRD), the Pearl River Delta (PRD), the Chengyu Basin (CY), and the Fenwei Plain (FW). The CMAQ model successfully reproduced the air pollutants in all the regions with model performance indices meeting the suggested benchmarks. However, over-prediction of PM2.5 was noted in CY. NO2, O-3,O- and PM2.5 were well simulated in the north compared to the south. Nitrate (NO3-) and ammonium (NH4+) were the most important PM2.5 components in heavily polluted regions. For the performance on different pollution levels, the model generally over-predicted the clean days but underpredicted the polluted days. O-3 was found increasing each year, while other pollutants gradually reduced during 2013-2019 across the five regions. In all of the regions except PRD (all seasons) and YRD (spring and summer), the correlations between PM2.5 and O-3 were negative during all four seasons. Low-to-medium correlations were noted between the simulated PM2.5 and NO2, while strong and positive correlations were established between PM2.5 and SO2 during all four seasons across the five regions. This study validates the ability of the CMAQ model in simulating air pollution in China over a long period and provides insights for designing effective emission control strategies across China.

Impact of the COVID-19 pandemic on patients receiving intravitreal injections

We analyzed the economic benefits versus safety risks of sharing anti-vascular endothelial growth factor (VEGF) vials during the coronavirus disease (COVID-19) pandemic. This single-center retrospective study analyzed the data of patients with neovascular age-related macular degeneration (nAMD), proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO) who received anti-VEGF between January 2016 and July 2021 at Renmin Hospital, Wuhan University, China. Costs were compared of the two protocols of intravitreal injections (IVIs) of ranibizumab, aflibercept and conbercept after (i) splitting the vial content for use in two patients and after (ii) disposal of the remaining vial content after use in a single patient, with the COVID-19 outbreak considered as the demarcation point. The incidence rates of post-injection endophthalmitis (PIE) preand post-outbreak were analyzed. The mean cost of a single IVI increased by 33.3%, from 3917.67±71.69 to 5222.67±84.98 Chinese Yuan during the pandemic. The incidences of IVI-related culture-positive PIE were 0.0134% (3 in 22448) and 0.0223% (1 in 4479), respectively, before and after the pandemic (P=0.6532). We conclude that vial sharing of IVIs in a large clinical institution is not associated with increased PIE risk and can significantly reduce the cost of therapy. © 2022