Variations in the Spatial Distribution of Smart Parcel Lockers in the Central Metropolitan Region of Tianjin, China: A Comparative Analysis before and after COVID-19

The COVID-19 pandemic has led to a significant increase in e-commerce, which has prompted residents to shift their purchasing habits from offline to online. As a result, Smart Parcel Lockers (SPLs) have emerged as an accessible end-to-end delivery service that fits into the pandemic strategy of maintaining social distance and no-contact protocols. Although numerous studies have examined SPLs from various perspectives, few have analyzed their spatial distribution from an urban planning perspective, which could enhance the development of other disciplines in this field. To address this gap, we investigate the distribution of SPLs in Tianjin's central urban area before and after the pandemic (i.e., 2019 and 2022) using kernel density estimation, average nearest neighbor analysis, standard deviation elliptic, and geographical detector. Our results show that, in three years, the number of SPLs has increased from 51 to 479, and a majority were installed in residential communities (i.e., 92.2% in 2019, and 97.7% in 2022). We find that SPLs were distributed randomly before the pandemic, but after the pandemic, SPLs agglomerated and followed Tianjin's development pattern. We identify eight influential factors on the spatial distribution of SPLs and discuss their individual and compound effects. Our discussion highlights potential spatial distribution analysis, such as dynamic layout planning, to improve the allocation of SPLs in city planning and city logistics.

An Examination of the Spatial Spillover Effects of Tourism Transportation on Sustainable Development from a Multiple-Indicator Cross-Perspective

Tourism is linked to multiple dimensions, such as the economy, society, and environment, and the relationships among its influencing factors are complex, diverse, and overlapping. This study constructed an evaluation index system to measure the degree of coordinated development of tourism, transportation, and the regional economy, then built a tourism-transportation-based Spatial Durbin Model (SDM) regarding the process of the coordinated development of tourism in the Beijing-Tianjin-Hebei region (BTHR) from 2010 to 2020. This paper explains the current status of sustainable tourism development in the BTHR and the impact and spillover effects of transportation on tourism development. The results show that the normalized tourism coordinated development index (NTCDI) of the BTHR increased from 13.61 in 2010 to 18.75 in 2019, then decreased to 14.45 in 2020. The results of SDM show that different transportation modes have different spillover effects on tourism. Specifically, civil aviation transportation has a positive impact and significant spillover on a city's tourism revenue (TR), while high-speed railway transportation has a negative spillover effect. The model results also show that the degree of openness of the city and city economic development level have significant positive effects and spillover effects on tourism development. Finally, the implications of related variables are discussed, and some suggestions are put forward on tourism development in the BTHR. However, there are some limitations in this study. In the future, international cooperation and data sharing will be strengthened, and multivariate methods such as social network analysis, artificial intelligence, and machine learning will be further integrated to achieve accurate simulation and prediction of the spatial spillover effects of tourism transportation.

Influence of COVID-19 prevention and control measures on incidence of notifiable infectious diseases in Jiading district, Shanghai

Objective: To analyze the changes in incidence of notifiable infectious diseases in Jiading district of Shanghai in the context of COVID-19 epidemic. Methods: The incidence data of notifiable infectious disease in Jiading during 2017-2021 were collected for the comparison of the incidence rates before and after the implementation of COVID-19 prevention and control measures. Results: The incidence rate of notifiable infectious diseases in Jiading was 167.59/100000 in 2020, 60.20% lower than the average level during 2017-2019 (421.04/100000) (X2=2424.369, P < 0.001)and the incidence rate was 213.82/100000 in 2021, 49.22% lower than the average level during 2017-2019 (X2=1 578.996, P < 0.001). The incidence of class B and C infectious diseases in 2020 and 2021 were lower than the average incidence during 2017-2019, and the incidence of class B infectious diseases decreased by 38.79% in 2020 and 30.70% in 2021, respectively. The incidence rate of class C decreased by 71.23% in 2020 and 58.76%in 2021, respectively. The incidence rates of intestinal infectious disease, respiratory infectious disease, blood infectious disease and sexually transmitted disease during 2020-2021 were lower than the average levels during 2017-2019, which decreased by 59.27%, 68.02% and 36.52% respectively in 2020, and decreased by 37.96%, 56.37% and 30.51% respectively in 2021. The incidence rates of HFMD in 2020 and 2021 were still highest during 2020-2021 (39.01/100000 and 75.87/100000). Conclusion: The implementation of COVID-19 prevention and control measures had influence on the incidence of notifiable infectious diseases with different transmission routes, especially the respiratory infectious diseases, but the influence on the rank of top five notifiable infectious diseases was not obvious.

Awareness and needs of parents regarding pediatric infectious diseases in kindergartens in Chenghua District of Chengdu

Objective: To understand the awereness and health needs of parents in regards to infectious diseases in kindergartens in Chengdu, and to provide a reference for carrying out targeted health education on infectious diseases. Methods: The parents of kindergarten children in Chenghua District of Chengdu was selected by convenient sampling, and a self-designed questionnaire was used. Results: The rate of awareness among parents regarding pediatric infectious diseases was 42.0%, among which the awareness rate of "treatment measures following a dog bite" was the highest (99.6%), and "the awareness rate of infectious disease classifications in China" was the lowest (26.7%). The awareness rate was related to family role, education level, occupation and income level (X2=10.81, 71.81, 93.78, 25.17, P < 0.05). The survey examined the demand for knowledge regarding pediatric infectious disease prevention and control, and revealed that parents primarily obtained such information from the school class group (85.5%). The most desirable way of obtaining relevant information was from information provided by professional institutions (96.6%), the infectious disease that parents most wanted to know about was the 2019 novel coronavirus (91.9%), and the most desirable time to acquire knowledge about infectious diseases depended on the seasonal arrangement of infectious diseases (67.5%). Conclusion: The awareness rate of parents about children's infectious diseases is in the middle level, and the channels for acquiring the knowledge about infectious diseases are relatively limited. Schools can carry out targeted health education in order to raise the awareness rate of parents of preschool children about children's infectious diseases.

Comparison of clinical manifestations, liver function, and antibody levels between omicron variant infection patients vaccinated and not vaccinated with COVID-19 vaccine

Objective: To compare the clinical manifestations, liver function, and antibody levels between Omicron variant infection patients vaccinated and not vaccinated with COVID-19 vaccine. Methods: Totally 430 convalescent COVID-19 patients infected with Omicron variant in Tianjin were selected, including 150 patients vaccinated with Corona Vaccine(Sinovac group), 185 patients vaccinated with BBIBP-CorV(Beijing biological group), 41 patients vaccinated with Ad5-nCoV vaccine(CanSino group), 16 patients vaccinated with Anhui Zhifei, Changchun Bio, Lanzhou Bio, Shandong Bio, other adenovirus vector vaccines or mixed vaccination(other group), and 38 unvaccinated patients(unvaccinated group). The clinical manifestations, liver function indexes [alanine aminotransferase(ALT), aspartate aminotransferase(AST), total bilirubin(TB), albumin(ALB), total protein(TP), lactate dehydrogenase(LDH)], and antibody levels(IgG, IgM)were compared retrospectively. Results: There was no statistical difference in the sex composition ratio among groups(P > 0.05). The age of the Beijing biological group was significantly lower than that of other groups, and the proportion of time less than 3 months from the last vaccination to admission in the Beijing biological group and CanSino group was significantly higher than that in the Sinovac group and other groups(all P < 0.01). A total of 110 children aged less than 16 years were enrolled, including 7, 88, 0, 1 and 14 cases in the Sinovac group, Beijing biological group, CanSino group, other group, and unvaccinated group, respectively. There were 6 asymptomatic cases, 13 moderate cases, 91 mild cases and 0 severe case. There was no significant difference in the abnormal rate of ALT between Beijing biological group and unvaccinated group(P > 0.05), but the abnormal rates of ALT were higher in the Sinovac group and CanSino group than in the unvaccinated group and Beijing biological group(all P < 0.05). The abnormal rate of AST in the unvaccinated group was higher than that in other groups(P < 0.05). There were no significant differences in AST, TP or TB among the groups(all P > 0.05). The levels of ALT were higher in the Sinovac group and CanSino group than in Beijing biological Group and unvaccinated group, the level of ALB in the unvaccinated group was lower than that in the other groups, and the level of LDH in the Beijing biological group was higher than those in the Sinovac group and CanSino group(both P < 0.05). The IgG and IgM antibody levels of the unvaccinated group were significantly lower than those of the Sinovac group, Beijing biological group and CanSino group(all P < 0.05). Conclusions: Omicron variant infection patients vaccinated with BBIBP-CorV are younger and have a higher proportion of mild conditions, which can protect the liver function of patients to a certain extent. Patients vaccinated with different COVID-19 vaccines can produce higher levels of IgG and IgM antibodies than the unvaccinated patients.

Heavy haze pollution during the COVID-19 lockdown in the Beijing-Tianjin-Hebei region, China.

To investigate the characteristics of particulate matter with an aerodynamic diameter less than 2.5 µm (PM2.5) and its chemical compositions in the Beijing-Tianjin-Hebei (BTH) region of China during the novel coronavirus disease (COVID-19) lockdown, the ground-based data of PM2.5, trace gases, water-soluble inorganic ions, and organic and elemental carbon were analyzed in three typical cities (Beijing, Tianjin, and Baoding) in the BTH region of China from 5-15 February 2020. The PM2.5 source apportionment was established by combining the weather research and forecasting model and comprehensive air quality model with extensions (WRF-CAMx). The results showed that the maximum daily PM2.5 concentration reached the heavy pollution level (>150 µg/m3) in the above three cities. The sum concentration of SO42-, NO3- and NH4+ played a dominant position in PM2.5 chemical compositions of Beijing, Tianjin, and Baoding; secondary transformation of gaseous pollutants contributed significantly to PM2.5 generation, and the secondary transformation was enhanced as the increased PM2.5 concentrations. The results of WRF-CAMx showed obviously inter-transport of PM2.5 in the BTH region; the contribution of transportation source decreased significantly than previous reports in Beijing, Tianjin, and Baoding during the COVID-19 lockdown; but the contribution of industrial and residential emission sources increased significantly with the increase of PM2.5 concentration, and industry emission sources contributed the most to PM2.5 concentrations. Therefore, control policies should be devoted to reducing industrial emissions and regional joint control strategies to mitigate haze pollution.

Analysis on the use of antiviral drugs for COVID-19 in Tianjin Haihe hospital from 2020 to 2021

Objective: To investigate and analyze the clinical classification and medication status of confirmed COVID-19 patients admitted to Tianj in Haihe Hospital, providing reference for rational use of antiviral drugs for COVID-19. Method: The sales volume and consumption sum of antiviral drugs for COVID-19 patients in Tianjin Haihe Hospital from January 21, 2020 to January 21, 2021 were collected for statistical analysis of DDDS, DDC, B/A and other indicators. Investigate the clinical classification of patients and the use of antiviral drugs, and evaluate the rationality of the use of antiviral drugs by referring to the COVID-19 Diagnosis and Treatment Protocol.

Analysis of air pollution characteristics, transport pathways and potential source areas identification in Beijing before, during and after the COVID-19 outbreak

A series of lockdown measures in response to the Corona Virus Disease 2019 (COVID-19) outbreak resulted in a drop in anthropogenic emissions and changes in concentrations of PM2.5 and O-3. Backward trajectories analysis, cluster analysis, potential source contribution function (PSCF) and concentration weighted trajectory (CWT) technologies were conducted to reveal the characteristics and potential source areas of pollutants in Beijing before the COVID-19 outbreak (BCO period), during the outbreak (COB period) and after the outbreak (ACO period), as well as the contemporaneous period in 2019 (CCO period), which is critical for exploring the efficient control measures and making policy. The results indicated that despite the significant reduction in anthropogenic emissions during the epidemic, the PM2.5 concentrations increased by 1.0% caused by unfavorable meteorological conditions. O-3 concentrations increased by 174.8% compared to that during the BCO period due to the increased temperature and inappropriate precursor reduction ratios. A considerable decrease of NO3- in PM2.5 was observed under the influence of significant reductions in vehicle emissions during the lockdown. The cluster analysis revealed that short-range transport played a significant role in the accumulation of local PM2.5 pollution, while long-range northwest airflows contributed more to O-3 accumulation, and weakened as the season changed. The PSCF and CWT analysis demonstrated that potential source areas of PM2.5 were mostly located in the central and southern Hebei, the southwestern Shandong in the CCO period, and expanded to central Inner Mongolia and northern Shanxi in the COB period. These areas were highly compatible with the high emission areas of the emission inventory statistics. After the outbreak, the source areas of O-3 were centered in the Beijing-Tianjin-Hebei region and Shandong province, with a radial dispersion in all directions, while they were distributed in the central Mongolia and Inner Mongolia during the other periods.

Genotyping, virulence genes and drug resistance of MRSA strains isolated from skin and soft tissue infection in Tianjin

OBJECTIVE: To investigate and analyze the genotyping, virulence genes and drug-resistant genes of methicillin resistant Staphylococcus aureus (MRSA) strains isolated from skin and soft tissue infections in this area. METHODS: The skin secretions of 204 patients with skin and soft tissue infections in the Fifth Central Hospital of Tianjin between Jan. 2019 and Dec. 2020 were collected, and MRSA strains identified as non-repetitive strains were isolated. The Staphylococcal cassette chromosome mec (SCCmec) and Staphylococcal protein A gene (spa) genotyping and Panton-valentine leukocidin (PVL) gene carrying status were analyzed among the MRSA strains, and their relationship with drug resistance was analyzed. RESULTS: Totally 82 strains of S. aureus were isolated from the skin secretions of 204 patients with skin and soft tissue infections, including 44 strains of MRSA (53.66%). The most common SCCmec genotype was genotype III (accounting for 84.09%) and the most common spa genotype was genotype t030 (accounting for 84.09%). PVL genes encoding virulence factors were amplified in 5 strains (11.36%). The drug resistance rates of 44 MRSA strains to vancomycin and compound sulfamethoxazole were 0.00%, and all the strains were drug-resistant to penicillin. Different SCCmec and spa genotypes were highly resistant to erythromycin, cefazolin, clindamycin and levofloxacin, but the differences in drug resistance rates of different SCCmec genotypes to clindamycin and levofloxacin were significant (P < 0.05). The resistance rates of strains with PVL positive genes to chloramphenicol, gentamicin and tetracycline were significantly higher than those with PVL negative genes (P < 0.05). CONCLUSION: Strains carrying SCCmec III and spa t030 genotypes may be the dominant strains of MRSA in skin and soft tissue infections in this area. Spa genotypes and PVL gene have certain impact on drug resistance of MRSA, and the isolated MRSA strains are all sensitive to vancomycin and compound sulfamethoxazole, which can provide a reference for anti-MRSA treatment in this area.

Significant reduction in atmospheric organic and elemental carbon in PM2.5 in 2+26 cities in northern China.

To better understand the change characteristics and reduction in organic carbon (OC) and elemental carbon (EC) in particulate matter (PM) with a diameter of ≤2.5 µm (PM2.5) driven by the most stringent clean air policies and pandemic-related lockdown measures in China, a comprehensive field campaign was performed to measure the carbonaceous components in PM2.5 on an hourly basis via harmonized analytical methods in the Beijing-Tianjin-Hebei and its surrounding region (including 2 + 26 cities) from January 1 to December 31, 2020. The results indicated that the annual average concentrations of OC and EC reached as low as 6.6 ± 5.7 and 1.8 ± 1.9 µg/m3, respectively, lower than those obtained in previous studies, which could be attributed to the effectiveness of the Clean Air Action Plan and the impact of the COVID-19-related lockdown measures implemented in China. Marked seasonal and diurnal variations in OC and EC were observed in the 2 + 26 cities. Significant correlations (p < 0.001) between OC and EC were found. The annual average secondary OC levels level ranged from 1.8-5.4 µg/m3, accounting for 37.7-73.0% of the OC concentration in the 2 + 26 cities estimated with the minimum R squared method. Based on Interagency Monitoring of Protected Visual Environments (IMPROVE) algorithms, the light extinction contribution of carbonaceous PM to the total amount reached 21.1% and 26.0% on average, suggesting that carbonaceous PM played a less important role in visibility impairment than did the other chemical components in PM2.5. This study is expected to provide an important real-time dataset and in-depth analysis of the significant reduction in OC and EC in PM2.5 driven by both the Clean Air Action Plan and COVID-19-related lockdown policies over the past few years, which could represent an insightful comparative case study for other developing countries/regions facing similar carbonaceous PM pollution.

Addressing External Shock in Urban Agglomeration: Implications From the Transmission Pattern of COVID-19 in the Beijing-Tianjin-Hebei Area.

Properly addressing external shocks in urban agglomeration is critical to sustaining the complex regional system. The COVID-19 pandemic has been widely acknowledged as an unintended external shock, but the temporal and spatial transmission patterns are largely ignored. This study analyzed the temporal and spatial transmission patterns of COVID-19 at the macro, meso, and micro levels, and proposes a conceptual model for regional comprehensive risk calculation, taking the Beijing-Tianjin-Hebei (BTH) area as the focus region. Our results showed that 1) at the temporal scale, the epidemic in the BTH area experienced stages of rapid increase, gradual decrease, and stabilization, and the first wave of the epidemic was under control from 23 February 2020; 2) at the spatial scale, confirmed cases were largely distributed at the terminal of the migration network, with closely interconnected cities in the BTH area, including Beijing, Tianjin, Tangshan, and Langfang, holding the highest comprehensive epidemic risk, thus requiring special attention for epidemic prevention and control. Finally, a "two-wheels" conceptual framework was built to discuss implications for future policies for addressing external shocks. Our proposed framework consists of an isolation wheel, which involves information sharing from the holistic perspective, and a circulation wheel, which emphasizes stakeholder involvement from the individual perspective. The findings of this study provide a knowledge basis for epidemic prevention and control as well as useful implications for addressing external shocks in the future.

Impact of the COVID-19 Epidemic on Population Mobility Networks in the Beijing-Tianjin-Hebei Urban Agglomeration from a Resilience Perspective

As an important symbol and carrier of regional social and economic activities, population mobility is a vital force to promote the re-agglomeration and diffusion of social and economic factors. An accurate and timely grasp on the impact of the COVID-19 epidemic on population mobility between cities is of great significance for promoting epidemic prevention and control and economic and social development. This study proposes a theoretical framework for resilience assessment, using centrality and nodality, hierarchy and matching, cluster, transmission, and diversity to measure the impact of the COVID-19 epidemic on population mobility in the Beijing-Tianjin-Hebei (BTH) urban agglomeration in 2020-2022, based on the migration data of AutoNavi and social network analysis. The results show that the COVID-19 epidemic had different impacts on the population network resilience of the BTH urban agglomeration based on the scale and timing. During the full-scale outbreak of the epidemic, strict epidemic prevention and control measures were introduced. The measures, such as social distancing and city and road closure, significantly reduced population mobility in the BTH urban agglomeration, and population mobility between cities decreased sharply. The population mobility network's cluster, transmission, and diversity decreased significantly, severely testing the network resilience. Due to the refinement of the epidemic control measures over time, when a single urban node was impacted, the urban node did not completely fail, and consequently it had little impact on the overall cluster, transmission, and diversity of the population mobility network. Urban nodes at different levels of the population mobility network were not equally affected by the COVID-19 epidemic. The findings can make references for the coordination of epidemic control measures and urban development. It also provides a new perspective for the study of network resilience, and provides scientific data support and a theoretical basis for improving the resilience of BTH urban agglomeration and promoting collaborative development.

VARIATION OF SATELLITE-DERIVED AEROSOL OPTICAL DEPTH OVER CHINA BEFORE AND AFTER THE COVID-19 PANDEMIC

Due to the Coronavirus Disease (COVID-19) pandemic, the human activities in China and even in the world were reduced in 2020, which also caused the variation of the atmospheric environment, especially atmospheric aerosol emissions. In this paper, the MODIS level-3 gridded atmosphere monthly global joint product in 2019 and 2020 were collected and processed. After preliminary analysis, we found that MODIS annual aerosol optical depth (AOD) over China in 2020 is generally lower than in 2019. In some regions such as Beijing-Tianjin-Hebei and Yangtze River Delta, AOD values dropped the most in February. However, in some months and regions, AOD in 2020 is even higher than in 2019. More studies are still ongoing. © 2021 IEEE.

Impact of Meteorological Conditions and Human Activities on Air Quality During the COVID-19 Lockdown in Northeast China

During the lockdown implemented to curb the spread of COVID-19, human activities have drastically reduced, providing a valuable opportunity to study and compare the impact of meteorological conditions and human activities on air quality. In this study, large-scale weather circulation, local meteorological conditions, and the impact of human activities are comprehensively considered, and changes in the concentration of major air pollutants in the northeast during this period are systematically studied. The large-scale weather circulation patterns that mainly affect the northeast region are divided into nine types by using the T-mode Principal components analysis objective circulation classification method. It is found that the northeast region is located at the edge of weak high pressure (Types 1, 2, and 7) and at the rear of high pressure (Type 4) and has higher concentrations of PM2.5, NO2, SO2, and CO;in cyclonic weather systems, low vortices (Types 3 and 5) and under the influence of the updraft (Type 6) in front of the trough, the ozone concentration is higher. The changes in the concentrations of PM2.5, NO2, CO, SO2, and O-3 in the three cities, namely Shenyang, Changchun, and Harbin, during the lockdown period are compared, and it is found that the concentrations of PM2.5, NO2, CO, and SO2 have a tendency to first decrease and then increase, while the changes of O-3 concentration are cyclical and increased significantly during this period. This demonstrates that pollutants such as PM2.5, NO2, CO, and SO2 are more susceptible to human activities and local meteorological conditions, and changes in O-3 concentration are more closely related to changes in weather circulation types. Finally, the FLEXPART-WRF model is used to simulate the pollution process of nine circulation types, which confirms that particulate pollution in the northeast is mainly affected by local emissions and local westward sinking airflow.

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.

An Industrial Heat Source Extraction Method: BP Neural Network Using Temperature Feature Template

Aiming at the problem of insufficient quantity and spatial refinement in the extraction of industrial heat source from annual scale thermal anomaly data, a neural network industrial heat source extraction method based on temperature feature template is proposed by using VIIRS active fire data. This study took Beijing-Tianjin-Hebei and its surrounding areas as the study area, Firstly, according to the spatial aggregation characteristics of industrial heat sources, the heat source objects were divided by the OPTICS algorithm. Secondly, according to the thermal radiation characteristics of the heat sources, the temperature characteristic template of industrial heat sources and non-industrial heat sources were constructed. Finally, the BP neural network was used to extract industrial heat source objects using the temperature feature template and heat source statistical characteristics as parameters. The results show that: (1) the extraction precision of industrial heat source of the neural network algorithm of temperature feature template proposed in this paper reached 96.31%. Compared with time filtering and logistic regression methods, the extraction precision of industrial heat sources was improved by 8.45% and 7.53%, respectively;(2) From 2015 to 2020, the number of industrial heat sources in the six provinces and cities in Beijing-Tianjin-Hebei and its surrounding areas decreased by 27.46%. The number of industrial heat source objects and heat anomalies in Hebei Province decreased by 8.06% and 7.44% annually, respectively, which was the largest decrease compared with other provinces and cities. The concentration of industrial heat sources in Shandong and Tianjin increased by 25.72% and 86.64%, respectively, indicating that the industrial transformation and upgrade policies in the two places have achieved remarkable results;(3) Tangshan, Handan, Lvliang, and Changzhi accounted for 31.37% of the total industrial heat sources in the study area, which are the main cities in Beijing-Tianjin-Hebei and its surrounding areas. The degree of industrial heat source accumulation and energy consumption in seven cities such as Linfen and Taiyuan was higher than those in other cities;The degree of industrial heat source accumulation and energy consumption in 11 cities such as Beijing and Zhoukou was lower than those in other cities;(4) From January to May 2020, the number of industrial heat anomalies in Beijing-Tianjin-Hebei and its surrounding areas remained unchanged or increased compared with the same period in 2019 and 2021. The COVID-19 had no significant impact on the industrial heat source in the study area. The number of industrial heat anomalies in Wuhan in January and February 2020 decreased by more than 66.67% compared with that in the same period in 2019 and 2021, the number of industrial heat anomalies from March to May 2020 was lower than that in the same period of 2019. The COVID-19 has had a significant impact on industrial heat sources in Wuhan from January to May 2020. This study reflects the current situation and trend of industrial heat source development in Beijing-Tianjin-Hebei and its surrounding areas, which provides a valuable reference for the formulation and adjustment of relevant policies such as reducing energy consumption and improving secondary industry concentration. © 2022, Science Press. All right reserved.

The effect of the systemic immune-inflammation index on conversion time of virus nucleic acid turning negative in COVID-19 patients

Objective: To investigate the effect of the systemic immune-inflammation index(SII) on the conversion time of virus nucleic acid turning negative in patients with coronavirus disease 2019(COVID-19).

Evolution of Urban Construction Land Structure Based on Information Entropy and Shift-Share Model: An Empirical Study on Beijing-Tianjin-Hebei Urban Agglomeration in China

Urban agglomerations are important carriers of the current world economic development and economic center of gravity shift, while urban construction land structure reflects and influences the functions and development directions of urban agglomerations and cities within them. It is significant to study the characteristics of urban construction land structure in urban agglomerations. Based on information entropy model and shift-share model, this study discusses and analyzes the evolution characteristics and spatial allocation differences of urban construction land structure in Beijing-Tianjin-Hebei urban agglomeration, and simulates the spatial allocation differences with the help of GIS technology. The empirical research results show that from, 2006 to 2017, the overall structure of urban construction land in Beijing-Tianjin-Hebei urban agglomeration changes alternately between “orderly” and “disorderly”, and finally the overall development was slightly disordered. Furthermore, there are significant differences in the competitiveness of different types of land in different cities. Among them, green land, public facilities land, and road traffic land show obvious replenishment effect, which are mainly distributed in Handan-Zhangjiakou northwestern Hebei, Tianjin-Cangzhou in the eastern coast, Baoding-Xingtai in central and southern Hebei, while industrial land and storage land, which are mainly distributed in Beijing-Tangshan-Langfang around the capital and Shijiazhuang-Handan-Hengshui in central and southern Hebei, show obvious crowding-out effect. In addition, the temporal changes and spatial allocation differences of urban construction land structure are influenced by many factors, such as economic development, industrial structure, population size, etc. Therefore, it is suggested that the coordinated development of urban agglomerations should adhere to the principle of “differentiated development before coordinated development, local coordinated development before overall coordinated development”.

Exploration for the application scope of interactive digital media in the prevention and control of COVID-19 epidemic in the community: interactive digital media design plan for garbage classification in Jingxianli community as an example

In the continuous prevention and control of the COVID-19 epidemic, community work has become an important basic unit for epidemic prevention and control. The prevention and control of the epidemic is inseparable from the maintenance of the community's health environment. Whether garbage can be properly and timely handled is the key to epidemic prevention and control. This research is based on the national and Tianjin municipal garbage classification policies, and analyzes the problems and difficulties of community waste classification during the epidemic period, and explores the auxiliary interactive design plan of garbage classification suitable for the "Jingxianli"community under the background of community epidemic prevention and control. © COPYRIGHT SPIE. Downloading of the is permitted for personal use only.

Persistent high PM2.5 pollution driven by unfavorable meteorological conditions during the COVID-19 lockdown period in the Beijing-Tianjin-Hebei region, China.

Lockdown measures to curtail the COVID-19 pandemic in China halted most non-essential activities on January 23, 2020. Despite significant reductions in anthropogenic emissions, the Beijing-Tianjin-Hebei (BTH) region still experienced high air pollution concentrations. Employing two emissions reduction scenarios, the Community Multiscale Air Quality (CMAQ) model was used to investigate the PM2.5 concentrations change in this region. The model using the scenario (C3) with greater traffic reductions performed better compared to the observed PM2.5. Compared with the no reductions base-case (scenario C1), PM2.5 reductions with scenario C3 were 2.70, 2.53, 2.90, 2.98, 3.30, 2.81, 2.82, 2.98, 2.68, and 2.83 µg/m3 in Beijing, Tianjin, Shijiazhuang, Baoding, Cangzhou, Chengde, Handan, Hengshui, Tangshan, and Xingtai, respectively. During high-pollution days in scenario C3, the percentage reductions in PM2.5 concentrations in Beijing, Tianjin, Shijiazhuang, Baoding, Cangzhou, Chengde, Handan, Hengshui, Tangshan, and Xingtai were 3.76, 3.54, 3.28, 3.22, 3.57, 3.56, 3.47, 6.10, 3.61, and 3.67%, respectively. However, significant increases caused by unfavorable meteorological conditions counteracted the emissions reduction effects resulting in high air pollution in BTH region during the lockdown period. This study shows that effective air pollution control strategies incorporating these results are urgently required in BTH to avoid severe pollution.