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1.
Applied Mathematics and Nonlinear Sciences ; 2022.
Article in English | Web of Science | ID: covidwho-2198284

ABSTRACT

This study uses the event study method to study and analyse the impact of the release of policy information related to the COVID-19 epidemic on the changes in the stock prices of listed companies of property service enterprises in China. The results show that the Hong Kong capital market has been greatly affected by the release of policy information related to the COVID-19 epidemic. Additionally, the study demonstrates that the policy effect of the introduction of policy information related to the COVID-19 epidemic exists in the short term, and that the effectiveness of policy information related to the COVID-19 epidemic will change over time.

2.
International Conference on Transportation and Development 2022, ICTD 2022 ; 6:134-142, 2022.
Article in English | Scopus | ID: covidwho-2050653

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has caused a reduction in business and routine activity and resulted in less motor fuel consumption. Thus, the gas tax revenue is reduced, which is the major funding resource supporting the rehabilitation and maintenance of transportation infrastructure systems. The focus of this study is to evaluate the impact of the COVID-19 pandemic on transportation infrastructure funds in the United States through analyzing the motor fuel consumption data. Machine learning models were developed by integrating COVID-19 scenarios, fuel consumptions, and demographic data. The best model achieves an R2-score of more than 95% and captures the fluctuations of fuel consumption during the pandemic. Using the developed model, we project future motor gas consumption for each state. For some states, the gas tax revenues are going to be 10%-15% lower than the pre-pandemic level for at least one or two years. © 2022 International Conference on Transportation and Development

3.
Maternal-Fetal Medicine ; 2(4):240-243, 2020.
Article in English | EMBASE | ID: covidwho-1612707

ABSTRACT

Fetal cardiac rhabdomyoma is associated with tuberous sclerosis complex (TSC) which is an autosomal dominant hereditary neurocutaneous disease with an incidence of approximately 1 in 5 000 to 10 000 live birth. It is caused by mutations in the TSC1 or TSC2 gene, de novo mutations accounting for approximately 80% of TSC cases, which can involve multiple organs and systems such as the heart, brain, kidney, lung, skin, and so on. Cardiac rhabdomyoma is the most common fetal heart tumor, accounting for about 60% of cases. It is closely related to TSC and may be the only manifestation of TSC which occurs during pregnancy. This study retrospectively analyzed the clinical data of a neonate with TSC diagnosed with fetal cardiac rhabdomyomas and confirmed by amniocentesis prenatal diagnosis as gene testing TSC1 gene positively. The parents had no such mutation. However, due to the influence of the sudden coronavirus disease 2019 (COVID-19) epidemic, the TSC genetic test report was not obtained until 38 weeks of pregnancy. Multiple hypo-pigmented spots (diameter >5 mm) were found immediately after birth. The characteristic cardiac feature of TSC is a rhabdomyoma and the diagnosis of TSC is based upon genetic testing and multiple ultrasound examinations or magnetic resonance imaging. Most patients with TSC have epilepsy, and one-half or more have cognitive deficits and learning disabilities. So rigorous follow-up will continue for the case we reported.

4.
International Eye Science ; 22(1):148-152, 2022.
Article in Chinese | EMBASE | ID: covidwho-1580279

ABSTRACT

AIM: To observe the epidemiological characteristics of myopia among primary school students in Xindu District of Chengdu before and after COVID-19 home isolation period (from Jan.-May 2020). METHODS: Cross-sectional study. A total of 10 153 primary school students from grade 1-6 (age 6-13, three classes per grade) were selected from four primary schools in Xindu District of Chengdu for three consecutive years (2018-2020), by using a random stratified cluster sampling method. All students' visual acuity and spherical equivalent refraction (SE) were measured, a further cycloplegia optometry was conducted for those whose visual acuity was less than 5.0. The SE was recorded and the prevalence of myopia was calculated. Chi-square test was used to compare the difference of prevalence of myopia between different years. One-way Anova was used to compare the difference of SE among different years. RESULTS: There was statistical difference in prevalence of myopia between the three years (2018: 35.98%, 2019: 36.29%, 2020: 42.52%;χ2=39.374, P<0.001). The prevalence of myopia among 6-9 years old students increased significantly in 2020 (P<0.01). They were 2.20 times (6 years old), 2.08 times (7 years old), 1.36 times (8 years old) and 1.24 times (9 years old) of the previous year. Students aged 6-9 years showed an obvious myopic shift in SE in 2020 (P<0.05). The increases were -0.34±0.76D (6 years old), -0.28±0.84D (7 years old), -0.29±1.41D (8 years old) and -0.18±1.35D (9 years old) than the previous year. The prevalence of myopia and SE remained stable among 10-13 years old students in 2018-2020 (P>0.05). CONCLUSION: After the COVID-19 home isolation period, there was a significant myopic shift among students aged 6-9 years old. We should pay more attention to the window period for myopia prevention and control of 6-9 years old.

6.
Bioorganic Chemistry ; 112:104889, 2021.
Article in English | MEDLINE | ID: covidwho-1208969

ABSTRACT

The emerging COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has raised a global catastrophe. To date, there is no specific antiviral drug available to combat this virus, except the vaccine. In this study, the main protease (M<sup>pro</sup>) required for SARS-CoV-2 viral replication was expressed and purified. Thirty-six compounds were tested as inhibitors of SARS-CoV-2 M<sup>pro</sup> by fluorescence resonance energy transfer (FRET) technique. The half-maximal inhibitory concentration (IC<sub>50</sub>) values of Ebselen and Ebsulfur analogs were obtained to be in the range of 0.074-0.91 muM. Notably, the molecules containing furane substituent displayed higher inhibition against M<sup>pro</sup>, followed by Ebselen 1i (IC<sub>50</sub> = 0.074 muM) and Ebsulfur 2k (IC<sub>50</sub> = 0.11 muM). The action mechanism of 1i and 2k were characterized by enzyme kinetics, pre-incubation and jump dilution assays, as well as fluorescent labeling experiments, which suggested that both compounds covalently and irreversibly bind to M<sup>pro</sup>, while molecular docking suggested that 2k formed an SS bond with the Cys145 at the enzymatic active site. This study provides two very potent scaffolds Ebsulfur and Ebselen for the development of covalent inhibitors of M<sup>pro</sup> to combat COVID-19.

7.
Kongzhi Lilun Yu Yingyong/Control Theory and Applications ; 38(1):130-136, 2021.
Article in Chinese | Scopus | ID: covidwho-1069945

ABSTRACT

Since the outbreak of COVID-19, lung diseases have attracted more attention. The characteristics and diagnosis of lung sounds become an important part of pulmonary pathology. The existing works for lung sound analysis mainly aim to classify the types of abnormal lung sounds. There are few studies focusing on the classification of lung diseases. Moreover, a single classification model cannot take advantage of the train data from multiple sources due to privacy leakage concerns, and it is difficult for complex models to classify in real time. Therefore, this paper proposes a model for classifying lung diseases based on ensemble knowledge distillation. Firstly, Mel-spectrum features were extracted from lung sounds, and then multiple binary convolutional neural network models were established as teacher models. Finally, a simplified multi-class student model will learn the knowledge of multiple teacher models through the technology of ensemble knowledge distillation. Our experiments show that the student model reduces 79% of the parameters and improves the prediction efficiency by 20% than teacher model while achieving a predictive accuracy of 95%. Under the same condition, the student model only incurs 6% of the time that is used by the state-of-the-art MobileNet-v3-small model. Thus, our model has potential to be deployed in real world for real-time diagnosis of the lung diseases. © 2021, Editorial Department of Control Theory & Applications South China University of Technology. All right reserved.

8.
Chinese Journal of Contemporary Pediatrics ; 22(4):294-298, 2020.
Article in Chinese | EMBASE | ID: covidwho-736852

ABSTRACT

Objective: To study the clinical features of children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Methods: A retrospective analysis was performed for the clinical data of 13 children with SARS-CoV-2 infection who hospitalized in a Changsha hospital. Results: All 13 children had the disease onset due to family aggregation. Of the 13 children, 2 had no symptoms, and the other 11 children had the clinical manifestations of fever, cough, pharyngeal discomfort, abdominal pain, diarrhea, convulsions, or vomiting. As for clinical typing, 7 had mild type, 5 had common type, and 1 had severe type. The median duration of fever was 2 days in 6 children. All 13 children had normal levels of peripheral blood lymphocyte counts, immunoglobulins, CD4, CD8, and interleukin-6. The median time to clearance of SARS-CoV-2 was 13 days in the nasopharyngeal swabs of the 13 children. Three children presented false negatives for RT-PCR of SARS-CoV-2. SARS-CoV-2 RNA remained detectable in stools for 12 days after the nasopharyngeal swab test yielded a negative result. Abnormal CT findings were observed in 6 children. All 13 children were cured and discharged and they were normal at 2 weeks after discharge. Conclusions: Intra-family contact is the main transmission route of SARS-CoV-2 infection in children, and there is also a possibility of fecal-oral transmission. Mild and common types are the major clinical types in children with SARS-CoV-2 infection, and cytokine storm is not observed. Children with SARS-CoV-2 infection tend to have a good short-term prognosis, and follow-up is needed to observe their long-term prognosis. Multiple nucleic acid tests should be performed for patients with SARS-CoV-2 infection and their close contacts by multiple site sampling.

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