A Survey of Multi-Agent Cross Domain Cooperative Perception

Intelligent unmanned systems for ground, sea, aviation, and aerospace application are important research directions for the new generation of artificial intelligence in China. Intelligent unmanned systems are also important carriers of interactive mapping between physical space and cyberspace in the process of the digitization of human society. Based on the current domestic and overseas development status of unmanned systems for ground, sea, aviation, and aerospace application, this paper reviewed the theoretical problems and research trends of multi-agent cross-domain cooperative perception. The scenarios of multi-agent cooperative perception tasks in different areas were deeply investigated and analyzed, the scientific problems of cooperative perception were analyzed, and the development direction of multi-agent cooperative perception theory research for solving the challenges of the complex environment, interactive communication, and cross-domain tasks was expounded.

Role of Government and Regulatory System of Medical Waste Recycling and Transportation Based on Game Theory

At the beginning of 2020, the COVID-19 broke out in China, and the use of medical supplies surged in various regions of China, resulting in an increase in the amount of medical waste. Against this background, the illegal industrial chain behind the medical waste has attracted more and more attention. This paper analyses the reasons for the emergence of the medical waste industry chain and the role of government supervision in the medical waste recycling system, and establishes the game relationship between manufacturers who can use medical waste as raw materials under the role of government supervision to choose raw materials. Finally, the setting of the government reward and penalty amount in the four numerical intervals and the corresponding game decisions of the manufacturers are obtained, to solve the problem of medical waste flow downstream of the industrial chain by changing the total yield of manufacturers. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Performance of urea-mediated dissociation in reducing false-positive of 2019-nCoV IgM test

Objective: To investigate the interference factors causing false-positive result of novel coronavirus IgM antibody detected by gold immunochromatography assay (GICA) and enzyme-linked immunosorbent assay (ELISA). Methods: A total of 71 serum from different pathogen infections and related chronic diseases patients were collected from the Affiliated Hospital of North Sichuan Medical College from January 22, 2020 to February 15, 2020. GICA and ELISA were used to detect 2019-nCoV IgM in 71 serum, including 5 influenza A virus (Flu A) IgM positive serum, 5 influenza B virus (Flu B) IgM positive serum, 5 Mycoplasma pneumonia (MP) IgM positive serum, 5 Legionella pneumophila (LP) IgM positive serum, 29 rheumatoid factor (RF) IgM positive serum, 5 hypertension patients serum, 5 diabetes mellitus patients serum, 6 human immunodeficiency virus (HIV) infection patients serum and 6 COVID-19 patients serum. The interference factors causing false positive results of the two methods were analyzed, and urea dissociation test was employed to dissociate the 2019-nCoV IgM positive serum using the best dissociation concentration. Statistical analyses were performed by SPSS, version 19.0. Results: 2019-nCoV IgM was positive in 18 cases of middle-high level RF-IgM positive serum and 6 cases of 2019-nCoV-infected serum detected by two methods, and the other 47 serum were negative. When the dissociation concentration of urea was 6 mol/L, 2019-nCoV IgM was negative in 17 cases of middle-high level RF-IgM positive serum and positive in 6 cases of 2019-nCoV-infected serum detected by GICA. When the urea dissociation concentration was 4 mol/L, dissociation time was 10 min and the avidity index<0.46 was set as negative, 2019-nCoV IgM was negative in 15 cases of middle-high level RF-IgM positive serum and positive in 6 cases of 2019-nCoV-infected serum detected by ELISA. Conclusion: The middle-high level of RF-IgM could cause false positive results of 2019-nCoV IgM detected by GICA and ELISA, and the urea dissociation test would be helpful for reducing the probability of false-positive results of 2019-nCoV IgM test.

[Biosafety in andrology laboratories during the outbreak of COVID-19]

The novel coronavirus disease 2019 (COVID-19) broke out in December 2019 and has been rapidly escalating throughout the world. Clinical findings show that the patients with either symptomatic or asymptomatic COVID-19 can be a potential source of infection. Although respiratory droplets and close contact are considered to be the main routes of transmission, there is the possibility of aerosol transmission in a relatively closed environment. The nucleic acid of the novel coronavirus can be detected in nasopharyngeal swabs, sputum and other lower respiratory tract secretions, blood, feces, urine and so on, but whether it exists in the semen has not been confirmed. It is reported that the novel coronavirus may affect the testis that highly expresses angiotensin-converting enzyme 2 (ACE2) and theoretically the semen is a possible carrier of the virus considering the fact that it is discharged from the same channel as the urine. Andrology laboratorians are exposed to most of the specimens above, including semen, and some open operations in the laboratory increase the risk of aerosol generation. Therefore, corresponding protective procedures are necessitated in andrology laboratories to reduce the risk of infection during the outbreak of COVID-19. Based on the knowledge and experience available as regards the pandemic and the characteristics of the work in the andrology laboratory, we summarize some biosafety points for andrology laboratorians to attend to during the outbreak of COVID-19.

Analysis of Urban Greenway Planning Strategies by the Orientation of Healthy City

In the first half-year of 2020, the COVID-19 (Coronavirus disease 2019) outbreak spread rapidly around the world. Under the impact of the crisis of Public Health Emergency, the development of healthy cities and people's lives must be experienced a tough test, and it will trigger the thinking and practice of urban construction as well. Taking the construction of Nanning greenway system as an example, and trying to discuss the route and the significance of healthy cities construction by greenway supporting, we came up with suggestions for greenway construction by the orientation of the concept healthy city. © The Authors, published by EDP Sciences, 2020.

Detection of 2019-nCoV nucleic acid in different specimens from confirmed COVID-19 cases during hospitalization and after discharge

Objective: To investigate the positive rates of 2019-nCoV nucleic acid in different specimens from confirmed COVID-19 cases during hospitalization and after discharge. Methods: Patients with confirmed COVID-19 were enrolled from designated hospitals. Nasal swabs, throat swabs, and specimens of stool, urine and blood were collected during hospitalization. After the patients were discharged, nasal swabs, throat swabs and stool specimens were collected during follow-up. Real-time RT-PCR was used to detect 2019-nCoV nucleic acid. Results: This study involved 25 confirmed COVID-19 cases. During hospitalization, all patients tested positive in both nasal and throat swab 2019-nCoV nucleic acid tests, and nine of them (36.00%) were positive in stool specimen test. Urine and blood specimen test results were all negative. Nasal swabs, throat swabs and stool specimens were collected from each patient 7 d and 14 d after discharge. Two patients (8.00%) tested positive for 2019-nCoV nucleic acid again in nasal and throat swab tests on 7 d, while all stool specimen tests were negative. No 2019-nCoV nucleic acid was detected in nasal swabs, throat swabs or stool samples on 14 d. Conclusions: 2019-nCoV nucleic acid was detected in stool samples of confirmed COVID-19 cases during hospitalization. Nasal and throat swab nucleic acid tests turned positive again in some patients after discharge.