ABSTRACT
Since the outbreak of COVID-19, there have been hundreds of millions of confirmed cases in the world, and people can strongly perceive the risk of infection with the virus in their daily lives, which has seriously affected people's life and travel, thus hindering the development of all sectors of society, especially the transportation sector. Taking China as an example, since the outbreak of the pandemic, China's overall public transportation passenger volume has decreased by about 37%, seriously affecting the normal running of the public transit. Therefore, the ways of ensuring the normal running of the public transport system during the pandemic has become the focus of this paper. In order to solve this problem, this paper constructed a SEM model based on pandemic risk perception, analyzed the impact of public transit pandemic prevention strategies (TPS) on risk perception (RP) and travel mode use according to the personal trip survey data in Harbin, China during the pandemic. The results showed that people's risk perception had a significant negative impact on car usage and transit usage. In other words, people's risk perception of virus infection had a great impact on travel, especially on the use of public transit. The transit pandemic prevention strategy had a significant negative impact on risk perception, and had a significant positive impact on people's use of transit. This showed that in the current pandemic outbreak period, the transit pandemic prevention strategy proposed by the Harbin authorities cannot effectively reduce transit usage, and can provide proven and effective transit pandemic prevention strategies. This provided an important support for ensuring the normal running of the public transit system and guiding the sustainable development of public transit during the outbreak of the pandemic.
ABSTRACT
Changzhou, a typical industrial city located in the center of the Yangtze River Delta (YRD) region, has experienced serious air pollution in winter. However, Changzhou still receives less attention compared with other big cities in YRD. In this study, a four-month PM2.5 sampling campaign was conducted in Changzhou, China from 1 November 2019, to 1 February 2020. The period covers the entire wintertime and includes first week of the Level 1 response stage of the lockdown period due to the outbreak of COVID-19. The mean PM2.5 concentrations were 67.9 +/- 29.0 mu gm(-3), ranging from 17.4 to 157.4 mu gm(-3). Secondary inorganic ions were the most abundant species, accounting for 37 and 50% during the low and high PM2.5 pollution periods, respectively. Nitrogen oxidation ratio (NOR) during the high PM concentration level period was twice the low PM concentration period whereas sulfur oxidation ratio (SOR) showed a less significant increase. This represents that nitrate formation is potentially the predominant factor controlling the occurrence of PM pollution. The analysis of NOR, SOR as functions of relative humidity (RH) and ozone (O-3) concentrations suggest that the sulfate formation was mainly through aqueous-phase reaction, while nitrate formation was driven by both photochemistry and heterogeneous reaction. And, excess ammonium could promote the formation of nitrate during the high PM period, indicating that ammonia gas played a critical role in regulating nitrate. Furthermore, a special period-Chinese New Year overlapping first week of COVID-19 lockdown period, offered a precious window to study the impact of human activity pattern changes on air pollution variation. During the special period, the average PM2.5 mean concentration was 60.4 mu gm(-3), which did not show in a low value as expected. The declines in nitrogen oxide (NOx) emissions led to rapid increases in O-3 and atmospheric oxidizing capacity, as well as sulfate formation. The chemical profiles and compositions obtained during different periods provide a scientific basis for establishing efficient atmospheric governance policies in the future.
ABSTRACT
The outbreak of SARS-CoV-2 has emphasized the value of point-of-care diagnostics, as well as reliable and cost-effective serological antibody tests, to monitor the viral spread and contain pandemics and endemics. Here, we present a three-dimensional (3D) nanofluidic device for rapid and multiplexed detection of viral antibodies. The device is made from poly(methyl methacrylate) and contains 3D fluidic channels with nanoscale topography variations on the millimeter length scale, enabled by combining gray-scale e-beam lithography and nanoimprint lithography. It works with capillary pumps only and does not require a complex microfluidic setup and pumps, which hinder the widespread usage of micro- and nanofluidic devices. The device is designed to size dependently immobilize particles from a multiparticle mixture at predefined positions in nanochannels, resulting in distinct trapping lines. We show that it can be used as an on-chip fluorescence-linked immunosorbent assay for highly specific and sensitive multiplexed detection of serological antibodies against different viral proteins. Further test flexibility is demonstrated by on-bead color multiplexing for simultaneous detection of IgG and IgM antibodies in convalescent human serum. The particle sorting is further leveraged to enable concurrent detection of anti-spike (SARS-CoV-2) and anti-hemagglutinin (influenza A) antibodies. The device's applications can be further extended to detect a large variety of diseases simultaneously in a reliable and straightforward manner.
ABSTRACT
Background: To analyze the clinical features of convalescent individuals with novel coronavirus-infected pneumonia (novel coronavirus pneumonia) at rehabilitation station in Wuhan. Methods: 712 patients in the convalescence period of novel coronavirus pneumonia isolated and observed at the rehabilitation station were investigated by collecting their basic data, clinical syndrome features, and tongue manifestations. The clinical syndrome features were analyzed based on guidelines of Diagnosis and Treatment Plan for Novel Coronavirus-infected Pneumonia (National Health Commission of the People's Republic of China, 7th Trial Edition). Results: Cough (24.86%), chest tightness and shortness of breath (23.17%), and fatigue (16.57%) were the main symptoms of patients in the convalescence period of novel coronavirus pneumonia. Their tongue appearance was mostly characterized by redness (88.65%), thick coating (67.25%), greasy coating (49.78%) and white coating (76.86%). Conclusion: Compared with the ordinary / mild patients, cough and anorexia symptoms were more common in the severe / critical patients. In convalescent patients, red and fat tongue with thick greasy fur were common.
ABSTRACT
As a newly epidemic, 2019 coronavirus disease (COVID-19) with a concentrated outbreak poses a great challenge to medical treatment. The severe and critical patients are complex complicatied with the psychological problems, and the medical staff are overworked and under tremendous psychological pressure. The surgeon participated in emergency medical rescue could provide professional treatment for the patients combined with surgical diseases, as well as specialized training for the non-surgeon crew, to reduce surgical-related mortality. With the advantages of good team consciousness, strong aseptic concept and good psychological quality, the surgeons can quickly adapt to and carry out rescue work under the premise of good self-protection. Surgeons need to develop critical care management concepts and focus on the critical care support equipment. Some suggestions are put forward for the standardized training of resident surgeons to cultivate compound talents. It is hoped that this article can lead to the thinking of how to participate in the emergency medical rescue of infectious diseases among surgeons and provide some enlightenment for future surgical education.