Study on Dynamic Change of Land Usage in Hongta District Based on Sentinel-2

This work utilizes Sentinel-2A L1C remote sensing photographs from the years 2018, 2020, and 2022 to identify the different land use categories in the study area using the support vector machine (SVM) technique. The accuracy of categorization is greater than 90%. This research explores four factors of the dynamic change in land use in Hongta District from 2018 to 2022: the proportion of various types of land;the extent of something like the changing land usage;land use transfer;and the dynamic degree of the change in land use. According to the study's results, the proportion of cultivated and grassland land grew, while the quantity of barren and construction land fell by 1.90 percent, 0.03 percent, and 0.69 percent, respectively. The water system land portion of total area increased by 2.58 percent and 0.13 percent, respectively. After comparing the two research periods, the entire dynamic degree of the second stage is determined to be 3.5 percent lower than that of the first stage, and the pace of land use change is quite sluggish, which may be associated with the worldwide COVID-19 outbreak in 2020. The outcomes of the research may give the natural resources department the knowledge it needs to manage land resources properly. © 2023 SPIE.

Detection and quantification of sars-cov-2 wastewater treatment plants from different cities in chile, towards to a permanent sentinel surveillance.

Background: The quantification of SARS-CoV-2 in wastewater is a tool that allows determining the trend of viral circulation in a particular geographical area. Aim(s): To quantify the SARS-CoV-2 virus in 15 wastewater treatment plants in different Chilean cities to establish a comparison with the variables of: I) Active cases per 100,000 inhabitants;ii) daily positivity (novel cases);and iii) phases of the lockdown strategy. Method(s): SARS-CoV-2 was concentrated from wastewater samples. To obtain the number of virus genomes per liter, absolute quantification was performed using qRT-PCR. Result(s): Between January and June 2021, 253 samples were processed, all of which were positive for the presence of the virus. Likewise, it will be determined that the rate of active cases per 100,000 inhabitants is the variable that best fits the trends obtained with the quantification of the viral load in wastewater. Conclusion(s): The quantification of SARS- CoV-2 in wastewater as a continuous strategy is an efficient tool to determine the trend of the viral circulation in a delimited geographical area and, combined with genomic surveillance, it can constitute an ideal sentinel surveillance alert on future outbreaks.Copyright © 2022, Sociedad Chilena de Infectologia. All rights reserved.

Comprehensive surveillance of acute respiratory infections during the COVID-19 pandemic: a methodological approach using sentinel networks, Castilla y León, Spain, January 2020 to May 2022.

BackgroundSince 1996, epidemiological surveillance of acute respiratory infections (ARI) in Spain has been limited to seasonal influenza, respiratory syncytial virus (RSV) and potential pandemic viruses. The COVID-19 pandemic provides opportunities to adapt existing systems for extended surveillance to capture a broader range of ARI.AimTo describe how the Influenza Sentinel Surveillance System of Castilla y León, Spain was rapidly adapted in 2020 to comprehensive sentinel surveillance for ARI, including influenza and COVID-19.MethodsUsing principles and methods of the health sentinel network, we integrated electronic medical record data from 68 basic surveillance units, covering 2.6% of the regional population between January 2020 to May 2022. We tested sentinel and non-sentinel samples sent weekly to the laboratory network for SARS-CoV-2, influenza viruses and other respiratory pathogens. The moving epidemic method (MEM) was used to calculate epidemic thresholds.ResultsARI incidence was estimated at 18,942 cases per 100,000 in 2020/21 and 45,223 in 2021/22, with similar seasonal fold increases by type of respiratory disease. Incidence of influenza-like illness was negligible in 2020/21 but a 5-week epidemic was detected by MEM in 2021/22. Epidemic thresholds for ARI and COVID-19 were estimated at 459.4 and 191.3 cases per 100,000 population, respectively. More than 5,000 samples were tested against a panel of respiratory viruses in 2021/22.ConclusionExtracting data from electronic medical records reported by trained professionals, combined with a standardised microbiological information system, is a feasible and useful method to adapt influenza sentinel reports to comprehensive ARI surveillance in the post-COVID-19 era.

Respiratory syncytial virus surge in 2022 caused by lineages already present before the COVID-19 pandemic.

In 2022, Austria experienced a severe respiratory syncytial virus (RSV) epidemic with an earlier-than-usual start (Weeks 35/2021-45/2022) and increased numbers of pediatric patients in emergency departments. This surge came 2 years after a season with no cases detected as a result of coronavirus disease 2019 nonpharmaceutical interventions. We analyzed epidemiologic patterns and the phylodynamics of RSV based on approximately 30 800 respiratory specimens collected year-round over 10 years from ambulatory and hospitalized patients from 248 locations in Austria. Genomic surveillance and phylogenetic analysis of 186 RSV-A and 187 RSV-B partial glycoprotein sequences collected from 2018 to 2022 revealed that the 2022/2023 surge was driven by RSV-B in contrast to the surge in the 2021/2022 season that was driven by RSV-A. Whole-genome sequencing and phylodynamic analysis indicated that the RSV-B strain GB5.0.6a was the predominant genotype in the 2022/2023 season and emerged in late 2019. The results provide insight into RSV evolution and epidemiology that will be applicable to future monitoring efforts with the advent of novel vaccines and therapeutics.

Pan-Respiratory Disease Surveillance in Southeast Asia: Past, Present and Future

The Global Influenza Surveillance and Response System (GISRS) was established by WHO in 1952 to conduct surveillance for influenza to inform strain selection for seasonal vaccines and to monitor for influenza pandemics. In 2016 WHO initiated a pilot project to add RSV to influenza surveillance platforms;this was disrupted by the SARS CoV-2 pandemic, and SARS CoV-2 was the first pathogen to be incorporated into influenza sentinel surveillance on a wide scale. This resulted in a "GISRS-plus" surveillance network for influenza and SARS CoV-2 that is now being standardized by WHO. In the wake of the SARS CoV-2 pandemic, there is global interest and funding to support pan-respiratory disease surveillance, which could result in expanding influenza/SARS CoV-2 surveillance platforms to include other pathogens and enhancing event- and indicator-based surveillance. Challenges with expanding sentinel surveillance include overburdening sentinel surveillance systems, reduced number of samples collected and loss of data quality for influenza and SARS CoV-2;thus, other types of surveillance for respiratory diseases might also be considered. This talk describes CDC-supported influenza surveillance platforms in Southeast Asia and recent successes and challenges in adding SARS CoV-2 to this surveillance. It discusses potential risks and benefits to GISRS-plus surveillance created by including other pathogens. Finally, it discusses decision-making steps on which methods to use for collecting data on respiratory viruses.Copyright © 2023

Sentinel satellite data monitoring of air pollutants with interpolation methods in Guayaquil, Ecuador

In Ecuador, there is a limitation on air quality monitoring due to the cost of monitoring networks. Although air quality monitoring stations are instruments for air measurement, they do not cover an entire city due to their scope. Satellite remote sensing is now an effective tool to study atmospheric pollutants and has been applied to continuously assess a region and overcome the limitations of fixed stations. Despite the application of satellite data for air quality monitoring, there are some limitations, such as measurement frequency, cloud cover and wide spatial resolution, which do not allow the assessment of air pollution in cities. Therefore, downscaling, applying interpolation methods, is essential for continuous air quality monitoring at smaller scales. For this research, Nitrogen Dioxide (NO2) data from the Sentinel-5 satellite percussor was used in the city of Guayaquil for January–December 2020, which is considered before, during and after the COVID-19 quarantine. This mid-size port city does not have a permanent monitoring network, which prevents us from knowing the air quality. Due to the limitation of pixel size, this study used satellite data to apply interpolation techniques and reduce pixels to assess air quality. Two categories of interpolation were selected: deterministic and stochastic. The empirical Bayesian kriging (EBK) interpolation obtained a R2 of 0.9546, which was superior to the other methods applied. Therefore, the EBK method had the best accuracy for tropospheric NO2 concentration. Finally, the method used in this research can help monitor air quality in cities lacking continuous monitoring networks, as the reduction of the pixel size gives us a better pattern of pollutants.

COVID-19 impact on EuroTravNet infectious diseases sentinel surveillance in Europe.

BACKGROUND: The COVID-19 pandemic resulted in a sharp decline of post-travel patient encounters at the European sentinel surveillance network (EuroTravNet) of travellers' health. We report on the impact of COVID-19 on travel-related infectious diseases as recorded by EuroTravNet clinics. METHODS: Travelers who presented between January 1, 2019 and September 30, 2021 were included. Comparisons were made between the pre-pandemic period (14 months from January 1, 2019 to February 29, 2020); and the pandemic period (19 months from March 1, 2020 to September 30, 2021). RESULTS: Of the 15,124 visits to the network during the 33-month observation period, 10,941 (72%) were during the pre-pandemic period, and 4183 (28%) during the pandemic period. Average monthly visits declined from 782/month (pre-COVID-19 era) to 220/month (COVID-19 pandemic era). Among non-migrants, the top-10 countries of exposure changed after onset of the COVID-19 pandemic; destinations such as Italy and Austria, where COVID-19 exposure peaked in the first months, replaced typical travel destinations in Asia (Thailand, Indonesia, India). There was a small decline in migrant patients reported, with little change in the top countries of exposure (Bolivia, Mali). The three top diagnoses with the largest overall decreases in relative frequency were acute gastroenteritis (-5.3%), rabies post-exposure prophylaxis (-2.8%), and dengue (-2.6%). Apart from COVID-19 (which rose from 0.1% to 12.7%), the three top diagnoses with the largest overall relative frequency increase were schistosomiasis (+4.9%), strongyloidiasis (+2.7%), and latent tuberculosis (+2.4%). CONCLUSIONS: A marked COVID-19 pandemic-induced decline in global travel activities is reflected in reduced travel-related infectious diseases sentinel surveillance reporting.

Understanding Patient Experiences with Overactive Bladder

INTRODUCTION AND OBJECTIVE: Overactive bladder (OAB) is highly prevalent, affecting millions of Americans, and poses a significant symptom burden. The purpose of this study was to understand patient experiences with OAB and the impact of these experiences on OAB treatment. METHOD(S): People with symptoms of OAB were recruited from a tertiary care clinic and from an online health research portal to complete semi-structured interviews regarding their OAB experiences. The interviews were recorded, transcribed, coded, and inductively analyzed to identify emerging themes. RESULT(S): We performed 19 interviews and identified several key themes central to the patient experience, including symptom impact and severity, knowledge, stigma, self-efficacy, and regret. We considered these themes along the following stages of the patient's OAB journey. Symptom Development and Awareness: The routine of self-care is insidious and normalized, making realization of a lifestyle that is centered around voiding less obvious to patients, leading to a delay of care-seeking. Participants noted restrictions on all aspects of life. Adjectives used to describe symptom impact included "annoyance, depression, humiliation and desperation." Care-Seeking: Participants expressed coping behaviors during onset and gradual worsening of symptoms, however many recounted a "sentinel event" that heightened their severity perception and served as a cue to action. Routine primary care visit screenings and friend recommendations were additional cues to action. Reasons for careseeking delay included lack of OAB knowledge, stigma, and embarrassment. Experiences with Therapy: Participants recognized that treatment outcomes depended on their engagement. Some individuals regretted their lack of self-advocacy and self-efficacy. Participants highlighted internal barriers (forgetfulness, doubting treatment effectiveness) and external barriers (comorbidities, COVID- 19) to therapy adherence. Among those with high self-efficacy, fear of treatment failure, calendar tools, and social support networks facilitated treatment compliance (Figure 1). CONCLUSION(S): Living with OAB affects patients physically, mentally, and socially. Gaining a better understanding of OAB experiences can help physicians tailor their practice to meet patients' needs.

ASPO effect (Preventive and Compulsory Social Isolation) in the atmosphere of the southwest of the province of Buenos Aires, Argentina

In 2020, Argentina implemented Preventive and Compulsory Social Isolation (ASPO) in the context of the global pandemic caused by the COVID-19 virus. This historical event has led to a decline in economic activities and the movement of the population. Current studies show a decrease in greenhouse gases harmful to health in the atmosphere due to health measures applied to contain the virus. Southwest Buenos Aires (Argentine Republic) is not exempt from these effects. The article aims to analyze the variations of the NO2 levels in pre-pandemic scenarios and during the pandemic. These results indicated a gradual decrease of NO2 related to the decrease in traffic and anthropogenic activities throughout the region, with a significant impact in big cities.

Breast Cancer-Related Lymphedema and its Relationship to Major Landmark Trials in Surgical Oncology and Radiation Oncology

INTRODUCTION: Many landmark trials have challenged the need for extensive axillary surgery and radiation in breast cancer patients. De-escalation of axillary treatment could potentially result in less breast cancer-related lymphedema (BCRL). Our study aims to define the incidence and trends of BRCL over the last 15 years. METHOD(S): Since 2005, our institution has prospectively screened breast cancer patients for lymphedema during and after treatment with a Perometer. 2,334 women diagnosed with breast cancer with baseline arm volume measurements and at least 2 follow-up measurements were divided into 3 cohorts based on date of surgery (Cohort 1: 2005-2010, Cohort 2:2011-2016, Cohort 3: 2016-2022). The cohorts were selected to coincide with publications of the landmark trials NSABP B-32, ASCOG Z0011, ASCOG Z1071, and EORTC 10981-22023 AMAROS which demonstrated safety in reducing the number of axillary lymph node dissections (ALND). Lymphedema was defined as a relative volume change of 10% or greater from preoperative baseline at least 3 months post-operatively. In cases of bilateral surgery, the weight-adjusted arm volume change equation was utilized. Cohort, age, BMI, axillary surgery type, chemotherapy timing, radiation type, and surgery type were all included in the multivariate analysis. RESULT(S): The overall incidence of BCRL was 12.8%, with a 29.6% incidence for those undergoing ALND and a 6.4% incidence for those undergoing sentinel lymph node biopsy. While the number of ALND performed decreased between cohorts (Figure 1), there was no significant difference in BCRL between assigned cohorts (HR 1.02 (95% CI [0.69, 1.51], p=0.930 for cohort 3 vs cohort 1). On multivariate analysis, significant associations with development of BCRL were identified with older age (HR 1.02;95% CI [1.01, 1.03], p=0.002), higher BMI (HR 1.05;95% CI [1.04, 1.07], p< 0.0001) and ALND (HR increased the risk of (HR 3.67;95% CI [2.62, 5.13], p< .0001). Regional lymph node radiation was not significantly associated with BCRL. CONCLUSION(S): Despite a reduction in the number of ALND performed over time, we did not see a dramatic reduction in the incidence of BCRL. Interestingly, between cohort 2 and cohort 3 there was a stable incidence of ALND which could be related to the COVID pandemic with an increase in more advanced cancers and a decrease in the ability to screen patients for BCRL during that time period.

Changes in NO2 and O3 levels due to the pandemic lockdown in the industrial cities of Tehran and Arak, Iran using Sentinel 5P images, Google Earth Engine (GEE) and statistical analysis.

Air pollution has very damaging effects on human health. In recent years the Coronavirus disease (COVID-19) pandemic has created a worldwide economic disaster. Although the consequences of the COVID-19 lockdowns have had severe effects on economic and social conditions, these lockdowns also have also left beneficial effects on improving air quality and the environment. This research investigated the impact of the COVID-19 lockdown on NO2 and O3 pollutants changes in the industrial and polluted cities of Arak and Tehran in Iran. Based on this, the changes in NO2 and O3 levels during the 2020 lockdown and the same period in 2019 were investigated in these two cities. For this purpose, the Sentinel-5P data of these two pollutants were used during the lockdown period from November 19 to December 05, 2020, and at the same time before the pandemic from November 19 to December 05, 2019. For better results, the effect of climatic factors such as rain and wind in reducing pollution was removed. The obtained results indicate a decrease in NO2 and O3 levels by 3.5% and 6.8% respectively in Tehran and 20.97% and 5.67% in Arak during the lockdown of 2020 compared to the same time in 2019. This decrease can be caused by the reduction in transportation and socio-economic and industrial activities following the lockdown measures. This issue can be a solid point to take a step toward controlling and reducing pollution in non-epidemic conditions by implementing similar standards and policies in the future.

The epidemiological pattern of seasonal influenza in four sentinel sites in Iraq.

Introduction: Influenza is an acute viral infection with significant morbidity and mortality. It occurs annually each winter, which is called seasonal influenza, and is preventable through safe vaccine. Aim: The aim of this work is to know the epidemiological pattern of patients with seasonal influenza in Iraqi sentinel sites. Methods: A cross-sectional study was carried out on records of patients who attended four sentinel sites and registered to have influenza-like illness (ILI) or severe acute respiratory infection (SARI), and laboratory investigated. Results: The total number of cases was 1124; 36.2% of them aged 19-39 years; 53.9% were female; 74.9% lived in urban areas; 64.3% diagnosed as ILI; and 35.7% as SARI; 15.9% had diabetes, 12.7% had heart disease, 4.8% had asthma, 3% had a chronic lung disease, and 2% had hematological disease; 94.6% did not get influenza vaccine. About COVID-19 vaccine, 69.4% were not vaccinated, 3.5% got only one dose, and 27.1% completed two doses. Only the SARI cases needed admission; among them, 95.7% were cured. 6.5% were diagnosed with influenza-A virus, 26.1% had COVID-19, and 67.5% were negative. Among those with influenza, 97.3% had H3N2 subtype and 2.7% had H1N1 pdm09. Conclusions: The percentage of influenza virus in Iraq is relatively small. The age, classification of case (ILI or SARI), having diabetes, heart disease, or immunological disease, and taking COVID-19 vaccine have a significant association with influenza. Recommendations: It is needed for similar sentinel sites in other health directorates and for rising health education about seasonal influenza and its vaccine.

Genomic Surveillance of SARS-CoV-2 in Healthcare Workers: A Critical Sentinel Group for Monitoring the SARS-CoV-2 Variant Shift.

SARS-CoV-2 genome surveillance is important for monitoring risk groups and health workers as well as data on new cases and mortality rate due to COVID-19. We characterized the circulation of SARS-CoV-2 variants from May 2021 to April 2022 in the state of Santa Catarina, southern Brazil, and evaluated the similarity between variants present in the population and healthcare workers (HCW). A total of 5291 sequenced genomes demonstrated the circulation of 55 strains and four variants of concern (Alpha, Delta, Gamma and Omicron-sublineages BA.1 and BA.2). The number of cases was relatively low in May 2021, but the number of deaths was higher with the Gamma variant. There was a significant increase in both numbers between December 2021 and February 2022, peaking in mid-January 2022, when the Omicron variant dominated. After May 2021, two distinct variant groups (Delta and Omicron) were observed, equally distributed among the five Santa Catarina mesoregions. Moreover, from November 2021 to February 2022, similar variant profiles between HCW and the general population were observed, and a quicker shift from Delta to Omicron in HCW than in the general population. This demonstrates the importance of HCW as a sentinel group for monitoring disease trends in the general population.

An assessment of the current epidemiological and laboratory capacities for influenza-like illnesses and severe acute respiratory infection surveillance, Yemen 2022.

Background and Objectives: We aim to re-activate influenza sentinel surveillance system in Yemen after disruption related to repurposing for COVID-19 pandemic. WHO Country Office (CO) in collaboration with Yemen's Ministry of Public Health and Population (MOPH&P) jointly conducted an assessment mission to assess the current situation of the influenza sentinel surveillance system and assess its capacity to detect influenza epidemics and monitor trends in circulating influenza and other respiratory viruses of epidemic and pandemic potential. This study presents the results of the assessment for three sentinel sites located in Aden, Taiz, and Hadramout/Mukalla. Methodology: A mixed methods approach was used to guide the assessment process and to help achieve the objectives. Data were collected as follows: desk review of the sentinel sites records and data; interviews with stakeholders, including key informants and partners; and direct observation through field visits to the sentinel sites, MOPH&P and the Central Public Health Laboratory (CPHL). Two assessment checklists were used: assessment of sentinel sites for SARI surveillance, and checklist for assessment of availability of SARI sentinel surveillance. Results and Conclusion: COVID-19 has affected health systems and services, and this was demonstrated in this assessment. The influenza sentinel surveillance system in Yemen is not effectively functional; however, there is plenty of room for improvement if investment in the system's restructuring, training, building technical and laboratory capacities, and conducting continuous and regular supervision visits.

Varying numbers of acute wheezing cases presenting to paediatric emergency during the COVID-19 pandemic

Acute wheezing in children due to underlying asthma or airways hypersensitivity (including allergic rhinitis) can be exacerbated by infectious and non-infectious causes. Of the infectious causes, seasonal rhinoviruses are the most common. Particulate airborne pollutants (PM2.5, PM10) can also play a role. During the COVID-19 pandemic, we observed changes in the pattern of paediatric emergency department (PED) presentations for acute wheezing. In this retrospective observational cohort study, data was extracted for children (0-18 years) presenting to the PED during 2018-2021, whose illness episodes were coded as 'asthma' or 'viral induced wheeze', along with their age, ethnicity, gender, and clinical outcomes, from hospital databases. The Figure shows the number of PED presentations for acute wheezing during 2018-2021, with annotations to explain the changing patterns. The number of cases presenting during the pandemic years 2020-2021 were similar to those in 2018-2019 in the same months, except for April-June 2020, July-August 2020, November 2020 and January-March 2021. Decreases in PED presentations coincided with periods of enforced national and local lockdowns, likely due to parental reluctance to expose their children to SARS-CoV-2 in a hospital setting. In addition, fluctuations in the incidence of rhinovirus infections, as shown by national sentinel surveillance data, likely contributed to changes in case numbers. Higher and lower incidence of rhinovirus infections tended to increase and decrease the number of presentations, respectively. Surprisingly, the level of airborne particulates (PM2.5, PM10) showed no correlation with these PED presentations for acute wheezing.

Comparative retrieval approaches for concentrated Suspended Particulate Matter (CSPM) detection in the Ganges using Sentinel-2 and Cloud Computing

In this paper, there are four distinct models utilized for the retrieval of CSPM from the Sentinel 2A/2B satellite imageries by using cloud computing techniques. In this study, a comparative analysis of different CSPM models was carried out at three different sites (Haridwar, Varanasi, and Hooghly). The study reveals that there are significant changes in CSPM in the Ganges in three different periods such as pre, during, and post-COVID. Noteworthy, fewer anthropogenic activities have generated important transformations in aquatic environments during the COVID. © 2023 IEEE.

27th National IMI Congress

The proceedings contain 25 papers. The topics discussed include: altitude effect on melanoma epidemiology in the Veneto region: a pilot study;novel predisposition genes double a decreasing CDKN2A mutation rate: five years of (tele)- counselling and gene panel testing for hereditary melanoma within the Italian melanoma intergroup;genetic profiling of atypical deep penetrating NEVI (DPN);ultra-high frequency ultrasound monitoring of melanomas arising in congenital melanocytic nevi: a case series;a segmentation algorithm for skin melanoma regression;impact of the COVID-19 pandemic on primitive melanoma diagnoses at the IDI-IRCCS of Rome;a novel-algorithm combining static and dynamic features to identify melanoma in digital dermoscopy monitoring;and non-sentinel lymph node detection meanwhile sentinel lymph node biopsy in not-complete lymph node dissection era: a new technique for better staging and treating melanoma patients.

Changes in the Distribution of Air Pollutants (Carbon Monoxide) during the Control of the COVID-19 Pandemic in Jakarta, Surabaya, and Yogyakarta, Indonesia

The condition of the Coronavirus Disease 2019 (COVID-19) pandemic in 2020 characterizing DKI Jakarta, Surabaya, and Yogyakarta Provinces which have a high population density in 2019, necessitates implementing Large-Scale Social Restrictions (LSSR) to control or break the chain of the spread of COVID-19. The LSSR policy that limits community activities, be it business activities, transportation, and the industrial sector, will impact social activities and the environment due to the reduced intensity of community activities. Therefore, this study aimed to determine changes in the carbon monoxide (CO) levels in Jakarta, Surabaya and Yogyakarta during the prepandemic and during the pandemic. The method used is the tropospheric CO concentration extracted from the Sentinel-5P satellite data. The CO data were retrieved and calculated using Google Earth Engine. The COVID-19 pandemic reduced CO level by 19.7%, 14.9%, and 21%, respectively. The paired t-test shows no significant difference from before the COVID-19 pandemic, with a significance of 0.05. The highest pre-pandemic average and total CO concentration levels were 0.042 and 1.0198 mol/m2 in Yogyakarta, respectively, whereas the lowest during the pandemic were 0.02845 and 0.6828 mol/m2 in Surabaya. Overall, the three cities have a weak relationship between CO level and precipitation as well as temperatures and CO level © 2023, Journal of Ecological Engineering.All Rights Reserved.

Surface Subsidence Characteristics and Causes in Beijing (China) before and after COVID-19 by Sentinel-1A TS-InSAR

Surface subsidence is a serious threat to human life, buildings and traffic in Beijing. Surface subsidence is closely related to human activities, and human activities in Beijing area showed a decreasing trend during the Corona Virus Disease 2019 (COVID-19). To study surface subsidence in Beijing before and after the COVID-19 outbreak and its causes, a total of 51 Sentinel-1A SAR images covering Beijing from January 2018 to April 2022 were selected to derive subsidence information by Time Series Interferometry Synthetic Aperture Radar (TS-InSAR). The results of surface subsidence in Beijing demonstrate that Changping, Chaoyang, Tongzhou and Daxing Districts exhibited the most serious subsidence phenomenon before the COVID-19 outbreak. The four main subsidence areas form an anti-Beijing Bay that surrounds other important urban areas. The maximum subsidence rate reached −57.0 mm/year. After the COVID-19 outbreak, the main subsidence area was separated into three giant subsidence funnels and several small subsidence funnels. During this period, the maximum subsidence rate was reduced to −43.0 mm/year. Human activity decrease with the COVID-19 outbreak. This study effectively analysed the influence of natural factors on surface subsidence after excluding most of the human factors. The following conclusions are obtained from the analysis: (1) Groundwater level changes, Beijing's geological structure and infrastructure construction are the main reasons for surface subsidence in Beijing. (2) Seasonal changes in rainfall and temperature indirectly affect groundwater level changes, thereby affecting surface subsidence in the area. (3) The COVID-19 outbreak in early 2020 reduced the payload of Beijing's transportation facilities. It also slowed down the progress of various infrastructure construction projects in Beijing. These scenarios affected the pressure on the soft land base in Beijing and reduced the surface subsidence trend to some extent. © 2023 by the authors.

Integral Assessment of Atmospheric Air Quality in the Largest Cities of Russia Based on TROPOMI (Sentinel-5P) Data for 2019–2020

This paper considers the level of atmospheric air pollution of the 20 largest cities in Russia in 2019–2020. The data used for the study is initially collected by a TROPOMI instrument (on the Sentinel-5P satellite), including measurements of carbon monoxide, formaldehyde, nitrogen dioxide, sulfur dioxide, and aerosol (aerosol index). The measurements were obtained using the cloud-based platform, Google Earth Engine, which presents L3 level data available for direct analysis. The Tropomi Air Quality Index (TAQI) integrates available TROPOMI measurements into a single indicator. The calculation results showed that most of the cities under consideration (15 out of 20) have a low or higher than usual level of pollution. Formaldehyde (35.7%) and nitrogen dioxide (26.4%) play the main role in the composition of pollution particles. A significant share is occupied by sulfur dioxide (16.4%). The contribution of carbon monoxide and aerosol averages 10.8 and 10.6%, respectively. Air pollution in cities is caused by both natural (wildfires, dust storms) and anthropogenic (seasonal migrations of the population, restrictions due to the COVID-19 pandemic) factors. Estimating atmospheric pollution levels in urban areas using an integral index based on remote data (such as TAQI) can be considered as a valuable information addition to existing ground-based measuring systems within the multisensory paradigm.