Dynamic spillover between traditional energy markets and emerging green markets: Implications for sustainable development

This study employs the time-varying vector parameter autoregression model and Diebold-Yilmaz (2012, 2014) spillover approach to explore the static, net, dynamic and directional spillover effects between China's traditional energy and emerging green markets and the impact of the COVID-19 outbreak on spillover effects. Spillover networks are constructed to observe structural changes in the directional spillover of each target financial market before and after the pandemic's outbreak. Changes in hedging indicators of portfolios composed of two types of markets before and after the outbreak of COVID-19 are compared to provide directional guidance for investors to choose portfolios in the post-pandemic era. We found that the outbreak of the pandemic had a considerable impact on the volatility of various spillover effects of the studied markets. The total spillover level of the system increased rapidly by 18% in the early stages of the pandemic. Green bond was the largest net recipient of volatility spillovers in the whole system, followed by crude oil, while new energy was the largest net contributor of volatility spillovers in the whole system, followed by clean energy. After the outbreak, the hedging effectiveness of portfolios with long positions in traditional energy markets and short positions in emerging green markets improved significantly. In particular, a portfolio with long positions in the crude oil market and short positions in the green bond market is the best risk-hedging portfolio. © 2023 Elsevier Ltd

A more accurate mask detection algorithm based on Nao robot platform and YOLOv7

With the global outbreak of Corona Virus Disease 2019(COVID-19), many countries had made it mandatory for people to wear masks in public places. This paper proposed a novel mask detection algorithm RMPC (Restructing the Maxpool layer and the Convolution layer)-YOLOv7 based on YOLOv7 for detecting whether people wear masks in public places. The RMPC-YOLOv7 algorithm reconstructed the downsampling structure in the original YOLOv7 algorithm. We changed the stacking of the maxpooling layer and the convolutional layer. This enabled the feature information to be fully integrated to achieve the accuracy improvement of the new model. Through comparison experiments, our proposed RMPC-YOLOv7 had was improved 0.9% and 1.2% for mAP0.5 and mAP0.5:0.95, respectively. The experimental results demonstrated the feasibility of RMPC-YOLOv7. © 2023 IEEE.

Expert consensus on diagnosing & treating pediatric surgical diseases during the epidemic period of COVID -19.

Ever since late December 2019, corona virus disease 2019 (COVID -19) has been reported in China. It presents a general trend of a global pandemic. By consulting the relevant Chinese government regulations and the latest publications of COVID -19, more than 20 pediatric surgical specialists from China formulated the Expert Consensus of COVID -19 Prevention and Control Protocol. Suitable for clinical practices, it provides recommendations for children's hospitals and pediatric surgical institutions at domestic and abroad.Copyright © 2020 by the Chinese Medical Association.

One case of novel coronavirus pneumonia complicated with acute appendicitis in children.

Emergent laparoscopic appendectomy was performed for a boy of occult novel coronavirus pneumonia with a presenting symptom of acute appendicitis at Wuhan Children's Hospital. Postoperative lung computed tomography (CT) indicated a round dense shadow with slightly ground-glass-like margins in the dorsal segment of right lower lung. Pharyngeal swab nucleic acid test was positive for 2019-nCoV and thus a definite diagnosis of COVID-19 was made. Prior to the onset, he had close contacts with his grandmother with a definite diagnosis of COVID -19. It proved that intra-family transmission was an important transmission route for pediatric 2019-nCoV infection. In this case, the respiratory symptoms of COVID-19 were not obvious during an early stage. The major symptoms were nausea, vomiting and abdominal pain. For individuals coming from the epidemic area, with a history of exposure and developing acute surgical conditions, preoperative pulmonary CT scan is necessary for screening COVID-19.Copyright © 2020 by the Chinese Medical Association.

Effect of environmental factors on the concentration distribution of bioaerosols with different particle sizes in an enclosed space

COVID-19 has alerted us about the need to quantify the effect of different environmental factors on the concentration distribution of bioaerosols. An experimental investigation was carried out to evaluate the effect of environmental factors, including air temperature, relative humidity, airflow speed and ultraviolet (UV) radiation, on the potential dispersion risk of bioaerosols in an enclosed space by tracking the Serratia marcescens as the tiny organisms. Research results indicated that the concentration of bioaerosols is the highest at the indoor air temperature of 25°C among the tested conditions (20°C, 25°C, 30°C and 35°C). The particle size of bioaerosols can be influenced by temperature, resulting in changes in the amount of settling. Increasing relative humidity from 50% to 80% and airflow speed from 1.5 m/s to 2.2 m/s have a negative impact on the dispersion of bioaerosols as the amount of particle settlement increases accordingly. As for the UV radiation parameters, a better disinfection efficiency was achieved at a radiation distance of 40 cm in the tested range of 20–50 cm and a radiation exposure time of 30 min in the tested range of 10–50 min. This study delivered novel data for the concentration distribution of bioaerosol under different environmental factors for creating a safe indoor environment. © The Author(s) 2022.

Online preschool education optimization based on edge computing in the era of COVID-19

Under the influence of COVID-19, people's normal life and activities have been limited, such as the education of children, which leads to the emergence of online preschool education. Since online preschool education is large-scale and time-sensitive, the traditional network model cannot satisfy the needs of online education. In this paper, edge computing is adopted to optimize online preschool education, where a task unloading algorithm based on genetic algorithm (TUOGA) is designed to minimize the computing delay of terminal tasks. In order to verify the effectiveness and efficiency of the proposed algorithm, TUOGA is compared with two task offloading algorithms, and simulation results show that the proposed algorithm outperforms them in the aspect of time latency. © 2021 John Wiley & Sons, Ltd.

Intelligent classification of B-line and white lung from COVID-19 pneumonia ultrasound images using radiomics analysis

As two important features of COVID-19 pneumonia ultrasound, the B-line and white lung are easily confused in clinics. To classify the two features, a radiomics analysis technology was developed on a set of ultrasound images collected from patients with COVID-19 pneumonia in the study. A total of 540 filtered images were divided into a training set and a test set in the ratio of 7:3. A machine learning model was proposed to perform automated classification of the B-line and white lung, which included image segmentation, feature extraction, feature screening, and classification. The radiomic analysis was applied to extract 1688 high-throughput features. The principal component analysis (PCA) and the least absolute shrinkage and selection operator (LASSO) were used to perform feature screening for redundancy reduction. The support vector machine (SVM) was utilized to make the final classification. The confusion matrix was used to visualize the prediction performance of the model. In the result, the model with features selected using LASSO outperformed the model with PCA in terms of classification effectiveness. The number of high-throughput features closely related to the classification under the model with LASSO was 11, with the value of AUC, accuracy, specificity, precision and recall being 0.92, 0.92, 0.91, 0.92 and 0.92, respectively. Compared to the model with PCA, the values of the evaluation indicators of the model with LASSO increased by 13.94%, 13.26%, 15.79%, 22.23% and 5.66%, respectively. As a conclusion, the proposed models showed good performance in differentiation of the B-line and white lung, with potential application value in the clinics. © 2022 ACM.

Effect of environmental factors on the concentration distribution of bioaerosols with different particle sizes in an enclosed space

COVID-19 has alerted us about the need to quantify the effect of different environmental factors on the concentration distribution of bioaerosols. An experimental investigation was carried out to evaluate the effect of environmental factors, including air temperature, relative humidity, airflow speed and ultraviolet (UV) radiation, on the potential dispersion risk of bioaerosols in an enclosed space by tracking the Serratia marcescens as the tiny organisms. Research results indicated that the concentration of bioaerosols is the highest at the indoor air temperature of 25°C among the tested conditions (20°C, 25°C, 30°C and 35°C). The particle size of bioaerosols can be influenced by temperature, resulting in changes in the amount of settling. Increasing relative humidity from 50% to 80% and airflow speed from 1.5 m/s to 2.2 m/s have a negative impact on the dispersion of bioaerosols as the amount of particle settlement increases accordingly. As for the UV radiation parameters, a better disinfection efficiency was achieved at a radiation distance of 40 cm in the tested range of 20–50 cm and a radiation exposure time of 30 min in the tested range of 10–50 min. This study delivered novel data for the concentration distribution of bioaerosol under different environmental factors for creating a safe indoor environment.

Robust Pandemic Control Synthesis with Formal Specifications: A Case Study on COVID-19 Pandemic

Pandemics can bring a range of devastating consequences to public health and the world economy. Identifying the most effective control strategies has been the imperative task all around the world. Various public health control strategies have been proposed and tested against pandemic diseases (e.g., COVID-19). We study two specific pandemic control models: the susceptible, exposed, infectious, recovered (SEIR) model with vaccination control;and the SEIR model with shield immunity control. We express the pandemic control requirement in metric temporal logic (MTL) formulas. We then develop an iterative approach for synthesizing the optimal control strategies with MTL specifications. We provide simulation results in two different scenarios for robust control of the COVID-19 pandemic: one for vaccination control, and another for shield immunity control, with the model parameters estimated from data in Lombardy, Italy. The results show that the proposed synthesis approach can generate control inputs such that the time-varying numbers of individuals in each category (e.g., infectious, immune) satisfy the MTL specifications with robustness against initial state and parameter uncertainties.

Immune response gene expressions in COVID-19 patients associate with disease severity

Background: Dysregulated immune responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are thought to underlie the progression of coronavirus disease 2019 (COVID-19). We sought to further characterize host antiviral and cytokine gene expression in COVID-19 patients based on illness severity. Methods: In this case-control study, we retrospectively analyzed 46 recovered COVID-19 patients and 24 healthy subjects (no history of COVID-19) recruited from the Second People's Hospital of Fuyang City. Blood samples were collected from each study participant for RNA extraction and PCR. We assessed changes in antiviral gene expression between healthy controls and patients with mild/moderate (MM) and severe/critical (SC) disease. Results: We found that type I interferon signaling (IFNA2, TLR8, IFNA1, IFNAR1, TLR9, IRF7, ISG15, APOBEC3G, and MX1) and genes encoding proinflammatory cytokines (IL12B, IL15, IL6, IL12A and IL1B) and chemokines (CXCL9, CXCL11 and CXCL10) were upregulated in patients with MM and SC disease. Moreover, we found that IFNA1, apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G (APOBEC3G), and Fas-associated protein with death domain (FADD) were significantly downregulated (P < 0.05) in the SC group compared to the MM group. We also observed that microRNA (miR)-155 and miR-130a levels were markedly higher in the MM group compared to the SC group. Conclusion: COVID-19 is associated with the activation of host antiviral genes. Induction of the IFN system appears to be particularly important in controlling SARS-CoV-2 infection, as decreased expression of IFNA1, APOBEC3G and FADD genes in SC patients, relative to MM patients, may be associated with disease progression.

A Qualitative Investigation of the Impact of COVID-19 on Macau's Gaining Industry

The purpose of this research note is to investigate the impact of COVID-19 on Macau's gaming industry. In-depth interviews were conducted with representatives of the six casino groups in Macau. The findings reveal that the casino business has been profoundly affected by the limitations on tourist mobility. In terms of casino operations, hygiene measures have been improved and even become a selling point. The pandemic has also led to weird atmosphere in the casinos, which affects both customers and casino management. Casinos have reduced labor costs without laying off employees. Finally, this study indicates that the gaming industry will remain the leading industry in Macau despite Covid-19. At the same time, collaboration and integration with the Guangdong-Hong Kong-Macau Greater Bay Area is the way of the future for Macau.

A Network for Detecting Facial Features during the COVID-19 Epidemic

The new coronavirus can spread through respiratory droplets, and wearing a mask correctly can effectively prevent the virus from spreading. However, the current detection algorithms are based on unobstructed faces, which affects the detection task when wearing a mask. To solve these problems, a facial feature detection algorithm based on Mtcnn+Mobilenet+GDBT in complex scenes is proposed. First, it can detect whether to wear a mask and the fatigue state of the face. Second, it can set different thresholds according to the facial characteristics of different people, and initialize the characteristics of different frames in 5 seconds. The innovation of our paper: the self-adaption characteristics for every person, it avoids measuring everyone by one standard, which is of great significance to the popularization of the product. Then train a dataset of masks and feature points containing 708 images. The experimental results show that compared with the traditional detection network, the new network can effectively detect facial features in the context of the epidemic. The loss we adopt is Focal loss. The lowest loss of net is 0.01 nearly. The feature of this paper is that before the outbreak of the new crown epidemic, the relevant model only designed the detection method of whether or not to wear the mask. On the basis of wearing the mask on the face, there is no research on the algorithm for judging the facial movements such as fatigue and drowsiness. This work adopts a two-step method, using the mature face detection network mtcnn, first detects the face, and then sends it into the mobilenet network for classification and monitoring status. This makes the model parameters smaller and the accuracy higher. Even if it is divided into two steps, the lightweight network of mobilenet can run smoothly on terminal devices, especially mobile devices. As for the fatigue detection system, the extraction of fatigue features with occlusions on the face has not been circulated on the network. Therefore, our team's innovation in fatigue detection based on facial occlusions such as masks has realized more dimensional detection, with stronger robustness and smaller limitations. In the future, it can be used in areas with severe influenza virus, factories, and sterile environments. It will be able to make judgments on the mask wearing conditions of on-site personnel through real-time images collected by the camera and remind people to wear masks correctly. During the epidemic, it is equipped with an on-board video system, which automatically records the driver's facial state. If fatigue performance such as frequent blinking is detected, the monitoring system will immediately issue an alarm to ensure safety. © 2021 ACM.

Investigation on and Protective Measures and Exposure Risks for the People Related to Medical Waste Disposal during the COVID-19 Epidemic

During the COVID-19, the production of medical waste increased sharply, which brought a challenge to the capacity of China's medical waste disposal and the protection of the group that received, transported and disposed of medical waste. In order to study the potential risks and protection measures against exposure for the workers in the collection, transportation, temporary storage, and disposal of medical waste, ninety staff members from a typical medical waste disposal center in Zhejiang Province were selected as the research objects to study the personal protection level of staff in different types of work, as well as the influence of items or locations at risk of infection on their choice of protective measures. The results show that among the 90 surveyed people, 98.9% of the staff wore medical respirators or full-face masks and half-masks during the work, 87.5% of the staff wore work clothes, 79.6% of the staff wore labor protection cap, 64.8% of workers chose to wear rubber gloves and protective boots for protection, and goggles (55.7%) and protective clothing (33.0%) were also worn when they were closely contact with medical waste. At the end of a single task, 100% of the respondents chose to wash their hands with running water, soap, quick disinfectant or 0.3%-0.5% iodophor disinfectant or bathe, and 94.3% of the respondents disinfected their personal work items;all respondents would take protective measures such as washing hands, disinfecting items, ventilating after returning home. The personal protection measures taken by different staff were mainly related to the items or locations that were exposed to risk of infection during the work process. Among them, the staff who were in contact with high-risk items, turnover containers (barrels) or the outer surface and inner wall of disposable packaging containers were more inclined to a higher level of protective measures. This research indicates that there is a significant difference between the qualified rate of protection and the type of work for the staff in this survey (P0.05). In the future, more detailed and specific policies and regulations should be formulated, and the management and training of the employees should be strengthened to increase their awareness of prevention and reduce the risk of occupational exposure. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

Transportation Activity Patterns of Chinese Population during the COVID-19 Epidemic

In order to understand the travel frequency and transportation modes of the Chinese population during the COVID-19 epidemic, the travel information of 8330 residents in 31 provinces from February 25th to March 14th, 2020 was collected, and the factors influencing the travel frequency and transportation mode were analyzed. According to the severity of the epidemic, 31 provinces were classified, and the difference in residents' transportation modes under different grades were analyzed and compared with those in non-epidemic periods. The results show that: (1) During the COVID-19 epidemic, 75.1% of people had travel activities, among which 5.5% took several trips per day and 17.6% took fewer than one trip per week. Public transportation and taxi with higher risk of infection were chosen by 6.3% and 4.0% of the population, respectively. (2) The travel frequency and transportation modes of Chinese residents during the COVID-19 outbreak may be affected by demographic variables, such as gender, age, urban and rural areas, regions, local or nearby suspected/confirmed cases, and the severity of the epidemic in the provinces. The travel frequency and transportation modes of people in some provinces such as Tibet Autonomous Region and Qinghai Province were less affected by the epidemic, while the travel frequency and transportation modes of residents in Hubei Province changed the most compared with the non-epidemic period. (3) During the COVID-19 epidemic, the proportion of Chinese residents who chose to walk and travel by car (taxi and private car) was much higher than during the non-epidemic period, while the proportion of people who chose public transportation and bicycles or electric bicycle was lower than during the non-epidemic period. This study found that the travel frequency and transportation modes of the Chinese population changed dramatically due to the COVID-19 epidemic. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

Ventilation Frequency and Duration of Chinese Population Opening Window during the COVID-19 Epidemic

Confined spaces increase the chance of aerosol infection, and window ventilation plays an important role in reducing the risk of infection and maintaining the fresh air required for human health. In order to analyze the window opening patterns of people in different regions during the COVID-19 outbreak, information on the frequency and duration of window ventilation and the demographic information were obtained through an electronic questionnaire survey, which surveyed 7784 subjects in 31 provinces in China. The ventilation behavior of different population and the main influencing factors were then analyzed. The results shows that: (1) During the COVID-19 epidemic, 99.7% of the subjects opened windows for ventilation;Among them, 69.2% of the subjects had more than two times of daily ventilation, and 38.2% had more than three times of daily ventilation, indicating a significant difference in ventilation frequency between different groups. (2) The daily ventilation duration of residents in each region was in the range of 93-126 min, and the ventilation duration for residents in the affected areas was longer. Compared with the non-epidemic period, the ventilation time of residents in all regions decreased significantly during the epidemic period. (3) The influencing factors of ventilation behavior of Chinese population during the epidemic mainly included the epidemic related factors and non-epidemic related factors. Among them, the epidemic related factors included control measures in the community and the distribution of hospitals around the community. The ventilation frequency was higher for the population, who resided in communities with epidemic control measures and nearby designated hospitals. The non-epidemic related factors included the type of dwelling, floor and ambient temperature. Compared with the units or apartments, the ventilation frequency of people living in bungalows was higher than those living in units or apartments. (4) Residents living in the middle floor of a flat or apartment building had the longest ventilation time, while those living on the lower floor had the shortest ventilation time. The window ventilation frequency and duration were positively correlated with the ambient temperature, that is, the ventilation frequency and duration of residents in areas with higher ambient temperature were higher than those in areas with lower ambient temperature. This study indicates that 99.7% of the residents had window ventilation behavior, and the daily ventilation time in various regions was in the range of 93-126 min during the COVID-19 epidemic, which was shorter than that during the non-epidemic period. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

Protective Behavior of Chinese Population Wearing Masks during the COVID-19 Epidemic

As a physical means to block virus infection, masks can stop the spread of pathogens through droplets, and have a two-way protection. Wearing masks is of great significant for the public to prevent the risk of novel coronavirus infection and maintain basic human health. In order to find out the mask wearing behavior of Chinese residents during the COVID-19 epidemic, this study analyzed the behavioral characteristics of residents wearing masks in China's 31 provinces, and discussed the differences of the behavior of wearing masks of the groups in various potential infection risk on the basis of the survey on environmental exposure behavior patterns of Chinese population during COVID-19 epidemic. The results show that: (1) During the COVID-19 epidemic, more than 99% of Chinese people wore masks outside their homes, which was significantly higher than that of non-epidemic period (16.05%);the highest proportion (100%) was the medical staff and the group who had extensive contact with people. (2) Residents mainly had three main patterns to wear masks, i.e., only surgical masks, only disposable surgical masks, and only surgical masks and disposable surgical masks, accounting for more than 60% of a total 31 mask wearing patterns. (3) During the COVID-19 epidemic, there were significant differences in the proportion of wearing masks among different occupational groups, people belonging to different groups and people in different epidemical areas. (4) During the COVID-19 epidemic, the replacement frequency of masks worn by Chinese residents was usually 4 and 24 hours, respectively. (5) The proportion of people wearing masks outside was positively correlated with the severity of the COVID-19 epidemic. Although there were differences of the epidemic distribution characteristics and control measures in different places, the proportion of residents wearing masks is high. Specifically, the proportion of people wearing masks in their living areas with no suspected cases was higher than that with suspected cases, indicating that there may be a certain interaction between the behavior of wearing masks and changes in epidemics. This study indicates that during the prevention and control of the COVID-19 epidemic, the mask wearing behavior of Chinese people was generally good. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.

Handwashing Behavior of Chinese Population during the COVID-19 Epidemic

Direct contact and droplet transmission are the main routes of novel coronavirus transmission. Reasonable handwashing behavior is an effective prevention and control measure to cut off the exposure routes and reduce the risk of virus infection, which may play an important role in the prevention and control of novel coronavirus pneumonia (COVID-19) epidemic. In this study, an electronic questionnaire was used to investigate the handwashing behavior and handwashing time of 8330 adults in 31 provinces in China during February 25th to March 14th, 2020, and the factors affecting hand-washing behavior in different exposure scenarios were then analyzed. The results show that the proportion and duration of hand-washing by women and urban residents were higher than that of men and rural residents, respectively. People were more likely to wash their hands in general exposure scenarios, while in scenarios with high risk of viral infections, such as after coughing or sneezing and after touching others, the proportion of handwashing was the lowest, 73.6% and 83.9%, respectively, indicating that the virus transmission routes and protection measures of this population need to be understood in depth. In terms of handwashing time, according to the standards of handwashing time (20 s) stipulated by WHO, only 41.7% of the population could reach the qualified level (that is more than 20 s), and the passing rate of urban residents' handwashing time was significantly higher than that in rural areas (42.0% vs. 39.7%). In general, the handwashing proportion of the people who went out was higher than those who never went out. Whether there were suspected and confirmed cases in the residential areas during the epidemic period had a significant impact on residents' handwashing behavior. However, the passing rate of handwashing time for the residents in the regions with the most severe epidemic was the lowest (37.2%), while the passing rate of handwashing time for the residents in the regions with the least epidemic was the highest (43.6%), indicating that the residents' hand-washing behavior may be affected by the epidemic and other factors. This study indicates that compared with non-epidemic period, the incidence of handwashing behavior among Chinese residents during the epidemic period increased, and the qualified rate of handwashing time was improved. However, the rate was still low. Thus, people's awareness of handwashing behavior should be improved, and the protective measures should be implemented scientifically. More attention should be paid to the anti-epidemic effect of handwashing when formulating relevant polices and personal protection. © 2020, Editorial Board, Research of Environmental Sciences. All right reserved.