Modelling and Closed-Loop Control of Admissions in a Vaccination Center Through Tropical Algebra

This paper presents the development of a dynamical tropical algebra-based model of a vaccination center, which can be used to control and optimize the admission of users during center's operation. In addition, an analysis of closed-loop control methods designed to maximize the system performance in terms of service rate and minimize users' waiting time, while observing occupancy constraints due to social distancing protocols recommended by sanitary authorities due to Covid epidemic, is presented. © 2023, Brazilian Society for Automatics--SBA.

Exposure to SARS-CoV-2 Aerosols in U.S. Residences: Sample analysis Using Two Detection Criteria

Uniform practices and quality control methods are needed to detect and quantify airborne viruses across sampling and analysis platforms. We compared detection of airborne SARSCoV-2 RNA in residences of individuals with COVID-19 using two commonly used criteria: environmental (at least one SARS-CoV-2-specific gene and internal control amplified by PCR with Ct ≤ 40) and clinical (at least two SARS-CoV-2-specific genes and internal control amplified with Ct ≤ 37). 24-hr total aerosol samples were collected in a self-isolation room and an additional room without manipulating subjects' behavior/activities. Under the environmental criterion, 7/16 samples in primary rooms and 7/15 samples in secondary rooms were positive. Comparable but lower positive sample proportions were observed using the more rigorous clinical criterion: 6/16 primary rooms and 5/15 secondary rooms. A consensus SARS-CoV-2 environmental sampling and analysis framework is needed for comparisons between studies. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

Evaluation of Optimal Mechanical Ventilation Strategies for Schools for Reducing Risks of Airborne Viral Infection

Ventilation systems are one of the most effective strategies to reduce the risk of viral infection transmission in buildings. However, insufficient ventilation rates in crowded spaces, such as schools, would lead to high risks of infection transmission. On the other hand, excessive ventilation rates might significantly increase cooling energy consumption. Therefore, energy-efficient control methods, such as Demand Control Ventilation systems (DCV), are typically considered to maintain acceptable indoor air quality. However, it is unclear if the DCV-based controls can supply adequate ventilation rates to minimize the probability of infection (POI) in indoor spaces. This paper investigates the benefits of optimized ventilation strategies, including conventional mechanical systems (MV) and DCV, in reducing the POI and cooling energy consumption through a detailed sensitivity analysis. The study also evaluates the impact of the ventilation rate, social distancing, and number of infectors on the performance of the ventilation systems. A coupling approach of a calibrated energy model of a school building in Jeddah, KSA, with a validated Wells–Riley model is implemented. Based on the findings of this study, proper adjustment of the DCV set point is necessary to supply adequate ventilation rates and reduce POI levels. Moreover, optimal values of 2 ACH for ventilation rate and 2 m for social distance are recommended to deliver acceptable POI levels, cooling energy use, and indoor CO2 concentration for the school building. Finally, this study confirms that increasing the ventilation rate is more effective than increasing social distancing in reducing the POI levels. However, this POI reduction is achieved at the cost of a higher increase in the cooling energy.

N-Step-Ahead Optimal Control of a Compartmental Model of COVID-19

This paper uses a compartmental model that accounts for some of the main features of the COVID-19 pandemic. Assuming a control that represents the aggregated intensity of non pharmaceutical interventions, such as lockdown in varying degrees and the use of masks and social distancing, this text proposes an N-step-ahead optimal control (NSAOC) method that is easy to calculate and provides a guideline for implementation. The compartmental model is extended to account for vaccination, and the N-step-ahead optimal control is calculated for this case as well. The proposed control is robust to parameter variation in all model parameters, when they are assumed to be normally distributed about nominal values. In addition, the proposed NSAOC is shown to compare favorably with a recently proposed PID-like controller. © 2023, Brazilian Society for Automatics--SBA.

Information-centric networking driven psychology recognition and health conduction of undergraduates

It is considerably significant to recognize the psychology of undergraduates especially during the period of COVID-19 outbreak. This letter proposes an Information-Centric Networking (ICN) driven psychology recognition and health conduction method based on the active data collection mode, that is, all undergraduates submit their psychology data to manger without protest by the special sensor tool. Meanwhile, the involved undergraduates and the management center construct a large network model. In order to support the mobility of undergraduates, this letter exploits ICN paradigm to help the management and transmission of psychology data. In addition, this management center deploys Deep Belief Network (DBN) to analyze the submitted psychology data. Finally, this letter makes a practical simulation on campus, and the experimental results show that the proposed psychology control method not only has good recognition effect but also contributes to health conduction. To be specific, the proposed method can improve about 2.6% psychology recognition accuracy and decrease about 46.5% psychology recognition time. © 2021 John Wiley & Sons, Ltd.

Staying proper with your personal protective equipment: How to don and doff.

INTRODUCTION: The global COVID-19 pandemic highlighted the importance of protecting frontline healthcare workers from novel respiratory infections while also exposing the limited instruction that medical students receive on proper donning of personal protective equipment (PPE) and more importantly the safe doffing of contaminated PPE to minimize their risk of nosocomial infection. The best methods of providing this kind of instruction have not yet been determined. METHODS: Anesthesiology interns and CA-1 residents were trained on proper PPE donning and doffing for AGPs using a methodology based on Miller's pyramid and following a "knows-knows how-shows-does" progression. Participants donned PPE without instruction and were sprayed with Glo Germ® to identify areas of contamination, after which they received both video and in-person instruction on best practices for donning and doffing PPE for AGPs. Following instruction, they again donned PPE and were sprayed with Glo Germ® to identify areas of contamination. RESULTS: 54 participants completed the study. Before training, overall donning compliance was 60% and overall doffing compliance was 48%. Overall, 70% were contaminated after PPE doffing, with 46% having multiple sites of contamination. After training, donning compliance increased by nearly 30% (P < 0.001), doffing compliance increased by over 20% (P < 0.001), and overall contamination decreased by nearly 30% (P = 0.029), with multiple-site contamination decreasing to only 6% (P = 0.013). DISCUSSION: While best methods for providing instruction regarding topics such as PPE donning and doffing have not yet been determined, we have demonstrated that the underlying knowledge base from medical school regarding proper donning and doffing for respiratory isolation is insufficient for preventing self-contamination, and that Miller's pyramid-based training using both video and in-person instruction combined with task execution by learners can improve compliance with PPE donning and doffing protocols and more importantly decrease skin contamination among a group of early training anesthesiology residents.

Research Progress of Residual Chlorine in Wastewater Effluent: Domestic Guideline Values, Monitoring and Control Methods

In China, chlorine-containing disinfectants are widely used in wastewater treatment. As pathogenic microorganisms are inactivated, residual chlorine concentration in wastewater effluent increase, posing ecological risks. During the COVID-19 pandemic, chlorine-containing disinfectants have been widely used, increasing residual chlorine problems. This study compared the guideline values of residual chlorine in various domestic and international discharge standards, summarized and analyzed the research progress of residual chlorine monitoring and control methods, and provide some suggestions for the formulation and revision of residual chlorine limits in pollutant discharge standards. The results show that: (1) The guideline values of residual chlorine were stipulated in some domestic discharge standards. As stipulated in Discharge Standard of Water Pollutants for Medical Organizations, the concentration of total residual chlorine in directly discharged hospital effluent should be lower than 0.5 mg/L. The integrated wastewater discharge standards of Beijing and Shanghai stipulated that the total residual chlorine concentration of all directly discharged wastewater should be lower than 0.5 mg/L. However, there are no guideline values of residual chlorine in the disinfected effluent of the WWTP (wastewater treatment plant). (2) Standard methods for monitoring residual chlorine included N, N-diethyl-1, 4-phenylenediamine titration and spectrophotometry. In recent years, instrumental analysis methods and sensor methods have also been developed rapidly for residual chlorine monitoring. (3) The residual chlorine control methods included chemical dechlorination with sulfur dioxide and sulfite as dechlorinating agents, activated carbon and reducing metal materials. As for the enlightenment, it is suggested that China should include the residual chlorine limit in the discharge standards of WWTP in the future, and pay attention to the development of residual chlorine monitoring and control methods and the formulation of the corresponding standards. © 2022 Editorial Board, Research of Environmental Sciences. All rights reserved.

Consume Machine Learning Integration Algorithms to Predict COVID-19 Infection

In the context of the emerging coronavirus pneumonia epidemic becoming a global epidemic, nucleic acid testing as a as a precise prevention and control method has been universally recognized, but because the scope of the test is too big and the production process is complicated, the kits produced by biological companies are difficult to use widely, for this reason I develop some machine learning integrated algorithms which can forecast whether a man is infected with COVID-19 based on three highly accessible features. This method can predict whether a person has been infected with COVID-19 based only on three indicators: heart rate, blood oxygen level, and body surface temperature, and we use several tree integration. We used several tree integration algorithms such as Random Forest, XGBoost, and GBM, and its accuracy, recall, and F1 score obtained 100% accuracy on the test set, which has been better than the current nucleic acid detection methods, proving that this method can be theoretically used as an accurate, convenient, and efficient self-detection method. © 2022 IEEE.

Corona strategy: what goals, what goals? [German]

In this report, three options for a long-term corona strategy are discussed developed and analyzed comparatively. In the case of option A ("The long dance with the virus"), politics continues to be exclusively oriented at the "intensive care bed threshold". Since this is currently far below, the restrictions can initially be relaxed much faster and more extensively than with the others options. A resurgence in new infections is tolerated, but the restrictions must be lifted and will be exacerbated again as case numbers approach the peak levels of March 2020. With option B ("descent until tracking"), the restrictions are controlled in such a way that the number of new infections is falling steadily. From this point, the strategy is limited to keeping the regional infection rate at a low level through intensive tracking and quarantine until the pandemic may one day be ended by a vaccine With option C ("Corona-free Germany from autumn"), the previous strict restrictions are retained in order to continue the fall in new infections observed in April at the same rate of decrease. New restrictions are being introduced at the external borders: goods traffic is to flow unhindered, but strict quarantine regulations apply to passenger traffic. In this way, it should be possible to be stable without new infections from autumn and thus to be able to lift all corona restrictions in Germany.

Information quality evaluation of corona virus disease 2019 direct online reporting in Guangzhou

Objective: To evaluate the quality of direct online reporting of corona virus disease 2019 (COVID-19), sum up experience, find existing problems, identify influencing factors, and suggest improvement measures to better guide future epidemic information reporting.

Research progress on characteristics, epidemiology and control measure of SARS-CoV-2 Delta VOC

COVID-2019 has become a global pandemic, and a variety of SARS-CoV-2 variants have emerged with the continuous evolution and variation. SARS-CoV-2 Delta VOC (B.1.617.2) has the characteristics of strong transmission, short incubation period of infection, high pathogenicity and rapid disease progression, which has gradually become the main epidemic strain in India and even in the world, leading to countries and regions of the epidemic rebound. In this paper, the current epidemic characteristics and core control measures of SARS-CoV-2 Delta VOC was reviewed.

Risk assessment of public health emergencies concerned in the mainland of China, June 2021

Objective: To assess the risk of public health emergencies, both the indigenous ones and the imported ones, which might occur in the mainland of China in June 2021. Methods: An internet based expert counsel was conducted to analyze the surveillance data of public health emergencies and priority communicable diseases in China reported through different channels, and the experts in all provincial centers for disease control and prevention attended this video conference. Results: Generally speaking, it is predicted that the incidence of public health emergencies would be similar in June with May. The risk of imported cases and secondary infections of COVID-19 would continue to exist, but would be controllable. It is the high incidence season of severe fever with thrombocytopenia syndrome and most cases would be sporadic, however, the risk of cluster exits especially in previous epidemic areas. The incidences of food poisoning caused by toxic animal or plant or poisonous mushroom would increase significantly, and the incidences of food poisoning caused by microbe would be high. The earthquake-stricken areas such as Yunnan and Qinghai should further strengthen post-disaster public health responses. The potential flood-stricken areas predicted by the meteorological department need to pay attention to the risks of water-borne, food-borne and vector-borne diseases that may increase after the disaster. Conclusion: Special attention should be paid to COVID-19, and general attention should be paid to severe fever with thrombocytopenia syndrome, food poisoning and natural disaster.

Impact of COVID-19 control measures on the spread of influenza

Objective: To analyze the effects of respiratory control measures before and after COVID-19 epidemic on influenza virus.

Construction of SEIQCR epidemic model and its application in the evaluation of public health interventions on COVID-19 in Guangzhou. (Special Issue: Spatio-temporal dynamics analysis, risk assessment and emergency management for COVID-19 epidemic.) [Chinese]

Objective To develop a dynamic model of susceptible(S), exposed people in the latent period(E), infective(I), quarantined(Q), confirmed(C), and recovered(R)(SEIQCR)to evaluate the role of interventions and control the coronavirus disease 2019(COVID-19)epidemic in Guangzhou. Methods Based on the SEIR propagation dynamics model, the modules of "quarantined" and "confirmed" cases were added to establish a new SEIQCR model. The epidemic data in Guangzhou from Jan. 13 to Mar. 17, 2020 were fitted to obtain the parameters of SEIQCR model. Results The number of predicted cases based on these parameters was highly consistent with the actual incidence(R2=0.93). Time-dependent reproduction number declined rapidly with the implementation of first level response to COVID-19, indicating that local transmission was effectively controlled. Conclusion The preventative and control measures were effective. Local government should continue strictly implementing the isolation system and cut off the transmission channels to curb the transmission of COVID-19. The SEIQCR model can provide methodological reference for intervention assessment in other regions.

Clustering distribution of COVID-19 in Wenzhou from January to March 2020 based on spatiotemporal analysis. (Special Issue: Spatio-temporal dynamics analysis, risk assessment and emergency management for COVID-19 epidemic.) [Chinese]

Objective: To explore the spatiotemporal distribution of COVID-19 in Wenzhou and to provide theoretical basis for the formulation of preventive and control measures.

Influence factors of COVID-19 in Shandong Province based on geographically weighted generalized linear model. (Special Issue: Spatio-temporal dynamics analysis, risk assessment and emergency management for COVID-19 epidemic.) [Chinese]

Objective: To explore the related influence factors of coronavirus diseases 2019(COVID-19)in Shandong Province and understand the regional distribution characteristics of the epidemic situation, and to provide a scientific basis for guiding prevention and control strategies.

Epidemic dynamics of COVID-19 in Xinyang City, Henan Province. (Special Issue: Spatio-temporal dynamics analysis, risk assessment and emergency management for COVID-19 epidemic.) [Chinese]

Objective: To explore epidemic dynamics of coronavirus disease 2019 (COVID-19) in Xinyang City so as to provide scientific basis for optimizing the prevention and control strategies and evaluating the effects of intervention.

Investigation and analysis of the characteristics of a family cluster of coronavirus disease 2019 in Zibo. (Special Issue: Spatio-temporal dynamics analysis, risk assessment and emergency management for COVID-19 epidemic.) [Chinese]

Objective: To investigate a family cluster of coronavirus disease 2019(COVID-19)in Zibo, so as to analyze the characteristics of the epidemic.

The Impact of COVID-19 on Online Games: Machine Learning and Difference-in-Difference

By intervening in people’s behavior, governments in several nations have established a variety of strategies to slow down the spread of COVID-19 pandemic. At the same time, it has a different impact on everyone. Data from the Steam platform online games between January 2018 and February 2021 was used for this project’s analysis. Through the difference-in-difference model in Synthetic Control Methods to quantify and analyze, crucial positive effect on Steam’s online players during COVID-19 and the increase of the number of online players and the released games of the platform in 2020 had been found. The machine learning prediction model was created using the daily totals of the online gaming players of the most popular games on the site. The Ridge regression, whose R squared reached 0.805, had been demonstrated by the experimental results that it got the best performance. Simultaneously, this work found the features of the COVID-19 pandemic and the features of the human mobility, which helps to build a great majority of the predictive models. © 2022, Springer Nature Singapore Pte Ltd.

A new stage for healthy China: new characteristics and urgency of public health

Building a strong public health system has become an urgent task in the new era. Based on more than eight years of systematic research, we believe that five aspects need to be prioritized for a strong system. First, we should change the perspective on public health, using the word "gonggong jiankang" to replace "gonggong weisheng" and the word "gonggong jiankang tixi" to replace "gonggong weisheng tixi", to lead the public health system development. Second, we should develop a suitable public health system and continuously improve the health capacity for governance. Third, we should make it clear that the goal of building a strong system is not far-fetched, and we need to consolidate the existing institutional advantages of China's public health system: when encountering major problems, we can maintain a unified goal and mobilize the whole society to cooperate effectively to accomplish the goal. However, we need to make up for shortcomings one by one, especially to solve the key problem of lacking a strong coordination mechanism in daily work. Fourth, we should pursue excellence and consolidate the "suitable" mechanism proven in the process of coping with the COVID-19, so that efficient mechanisms to deal with major issues can be used in routine work, and efforts should be made to consolidate the advantages of prevention and control of infectious diseases and emergency response, so as to achieve the balanced development of regions categories and units. Finally, it is necessary to strengthen the coordination of government and research institutions, in the aspects of technological innovation, talent team building and accurate consulting services, and work together to pursue a suitable and strong system to realize the modernization of the health system and capacity for governance.