ABSTRACT
In this study, we theoretically propose a surface plasmon resonance (SPR) biosensor composed of a plasmonic gold film, double negative (DNG) metamaterial, graphene-MoS2-COOH Van der Waals heterostructures and gold nanoparticles (Au NPs). We use a novel scheme of Goos-Hanchen (GH) shift to study the biosensing performances of our proposed plasmonic biosensor. The calculation results show that, both an extreme low reflectivity of 8.52x10(-10) and significantly enhanced GH sensitivity of 2.1530x10(7) mu m/RIU can be obtained, corresponding to the optimal configuration: 32 nm Au film/120 nm metamaterial/4-layer graphene/4-layer MoS2-COOH. In addition, there is a theoretically excellent linear response between the concentration of target analytes (SARS-CoV-2 and S protein) and the change in differential GH shift. Our proposed biosensor promises to be a useful tool for performing the novel coronavirus detection.
ABSTRACT
Persuasive information developed by smartphone applications is a potential tool that can be utilized in order to increase the effectiveness of the impact of pricing strategies on triggering sustainable travel mode choice behavior. In order to address the joint impacts of pricing strategies and persuasive information on habitual automobile commuters' travel mode shift responses, a stated-preference survey was conducted in Beijing's inner district, from which over 1000 responses were collected. Four separate multivariable multilevel logistic regression models were estimated for more and less habitual automobile commuters when subjected to congestion pricing and reward strategies. The model estimation results showed that the influence of persuasive information was more effective in promoting travel mode shifts among more habitual automobile commuters with regard to reward strategies compared to congestion pricing. The results also showed that the impact of sociodemographic characteristics, commuter travel characteristics, the amount of congestion pricing or monetary award, and types of persuasive information on travel mode shift decisions under these strategies were deemed to be significantly different between more and less habitual automobile commuters. These findings suggest that more effective reward strategies can be explored by providing personalized and differentiated travel feedback information (e.g., pollution emission information and physical activity information), particularly for less habitual automobile commuters. This study also provides some degree of insight regarding the question as to how to design future congestion pricing, i.e., with respect to formulating differentiated charge rates according to the travel characteristics of habitual automobile commuters, as well as in developing complementary persuasive information that focuses on addressing public acceptability and fairness rather than travel feedback information.
ABSTRACT
Coronavirus Disease-2019 (COVID-19) has been a major public health issue all over the world, placing a significant burden on available healthcare resources. The most common types of COVID-19 are the mild and common forms. Although the proportion of the severe-critical types is smaller, the rate of death is significantly higher and the medical resources required tend to be greater. Thus, a variety of scores based on other disease and COVID-19 were used to assess the risk of poor prognosis on the COVID-19, including the common scores for community-acquired pneumonia, sepsis and viral pneumonia. Unfortunately, the above scores often lacked an adequate description of the applicable population or were at high risk of bias with unknown applicability. Therefore, the article summarized the existing scores, aiming to provide a reference for clinical prognostic risk assessment.
Subject(s)
COVID-19 , Pneumonia, Viral , Humans , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Prognosis , Risk Assessment , SARS-CoV-2ABSTRACT
Recent pandemic outbreak of the corona-virus disease 2019 (COVID-19) has raised widespread concerns about the importance of the bioaerosols. Bioaerosols are an important part of atmospheric aerosols. Due to its physico-chemical properties and inherent biological characteristics, bioaerosols play a key role in global ecosystem, climate change, air quality and public health. A large number of studies have been focused on the sampling and detection techniques of bioaerosols, disinfection protection, effects on health and environment. However, little is known about the source characteristics of bioaerosols. Therefore, the research status of airborne microbes source was focused, and the progress on the emission characteristics of natural and anthropogenic source of bioaerosols in the past 20 years was comprehensively summarized. Combined with our study, the main factors affecting the source emission and transport process were also highlighted, such as biogeographic regions, land-use types, and environmental factors. Subsequently, the various source analysis methods of current bioaerosols were discussed. Finally, the future work prospects of bioaerosols source characteristics were prospected. It is expected to provide reference for in-depth understanding of the source and transmission change mechanism of bioaerosols, and to better evaluate the level of atmospheric microbial pollution and monitor the aerosol transmission of pathogens. © 2021, Editorial Department of Journal of Earth Sciences and Environment. All right reserved.
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Objective: To evaluate the efficacy and safety of lopinavir/ritonavir (LPV/r) and arbidol in treating patients with coronavirus disease 2019 (COVID-19) in the real world. Methods: The clinical data of 178 patients diagnosed with COVID-19 admitted to Guangzhou Eighth People's Hospital from January 20 to February 10, 2020 were retrospectively analyzed. According to patient's antiviral treatment regimens, 178 patients were divided into 4 groups including LPV/r group (59 patients), arbidol group (36 patients), LPV/r plus arbidol combination group (25 patients) and the supportive care group without any antiviral treatment (58 patients). The primary end point was the negative conversion time of nucleic acid of 2019 novel coronavirus (2019-nCoV) by pharyngeal swab. Results: The baseline parameters of 4 groups before treatment was comparable. The negative conversion time of viral nucleic acid was (10.20±3.49), (10.11±4.68), (10.86±4.74), (8.44±3.51) days in LPV/r group, arbidol group, combination group, and supportive care group respectively (F=2.556, P=0.058). There was also no significant difference in negative conversion rate of 2019-nCoV nucleic acid, the improvement of clinical symptoms, and the improvement of pulmonary infections by CT scan (P>0.05). However, a statistically significant difference was found in the changing rates from mild/moderate to severe/critical type at day 7 (χ(2)=9.311, P=0.017), which were 24%(6/25) in combination group, 16.7%(6/36) in arbidol group, 5.4%(3/56) in LPV/r group and 5.2%(3/58) in supportive care group. Moreover, the incidence of adverse reactions in three antiviral groups was significantly higher than that in supportive care group (χ(2)=14.875, P=0.002). Conclusions: Antiviral treatment including LPV/r or arbidol or combination does not shorten the negative conversion time of 2019-nCoV nucleic acid nor improve clinical symptoms. Moreover, these antiviral drugs cause more adverse reactions which should be paid careful attention during the treatment.
Subject(s)
COVID-19 Drug Treatment , HIV Infections , HIV Infections/drug therapy , Humans , Indoles , Lopinavir/adverse effects , Retrospective Studies , Ritonavir/adverse effects , SARS-CoV-2ABSTRACT
Objective To systematically summarize the clinical features of coronavirus disease 2019 (COVID-19) in children. Methods PubMed, Embase, Web of Science, The Cochrane Library, CNKI, Weipu Database, and Wanfang Database were searched for clinical studies on COVID-19 in children published up to May 21, 2020. Two reviewers independently screened the articles, extracted data, and assessed the risk of bias of the studies included. A descriptive analysis was then performed for the studies. Related indices between children with COVID-19 and severe acute respiratory syndromes (SARS) or Middle East respiratory syndrome (MERS) were compared. Results A total of 75 studies were included, with a total of 806 children with COVID-19. The research results showed that the age of the children ranged from 36 hours after birth to 18 years, with a male-female ratio of 1.21: 1. Similar to SARS and MERS, COVID-19 often occurred with familial aggregation, and such cases accounted for 74.6% (601/806). The children with COVID-19, SARS, and MERS had similar clinical symptoms, mainly fever and cough. Some children had gastrointestinal symptoms. The children with asymptomatic infection accounted for 17.9% (144/806) of COVID-19 cases, 2.5% (2/81) of SARS cases, and 57.1% (12/21) of MERS cases. The children with COVID-19 and MERS mainly had bilateral lesions on chest imaging examination, with a positive rate of lesions of 63.4% (421/664) and 26.3% (5/19) respectively, which were lower than the corresponding positive rates of viral nucleic acid detection, which were 99.8% and 100% respectively. The chest radiological examination of the children with SARS mainly showed unilateral lesion, with a positive rate of imaging of 88.9% (72/81), which was higher than the corresponding positive rate of viral nucleic acid detection (29.2%). Viral nucleic acid was detected in the feces of children with COVID-19 or SARS, with positive rates of 60.2% (56/93) and 71.4% (5/7) respectively. The children with COVID-19 had a rate of severe disease of 4.6% (31/686) and a mortality rate of 0.1% (1/806), the children with SARS had a rate of severe disease of 1.5% (1/68) and a mortality rate of 0%, and those with MERS had a rate of severe disease of 14.3% (3/21) and a mortality rate of 9.5% (2/21). Conclusions Children with COVID-19 have similar symptoms to those with SARS or MERS, mainly fever and cough. Asymptomatic infection is observed in all three diseases. Children with COVID-19 or SARS have milder disease conditions than those with MERS. COVID-19 in children often occurs with familial aggregation. Epidemiological contact history, imaging examination findings, and viral nucleic acid testing results are important bases for the diagnosis of COVID-19.