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1.
Frontiers in Immunology ; 13:939311, 2022.
Article in English | MEDLINE | ID: covidwho-2022716

ABSTRACT

Background: Owing to the coronavirus disease 2019 (COVID-19) pandemic and the emergency use of different types of COVID-19 vaccines, there is an urgent need to consider the effectiveness and persistence of different COVID-19 vaccines. Methods: We investigated the immunogenicity of CoronaVac and Covilo, two inactivated vaccines against COVID-19 that each contain inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The levels of neutralizing antibodies to live SARS-CoV-2 and the inhibition rates of neutralizing antibodies to pseudovirus, as well as the immunoglobulin (Ig)G and IgM responses towards the spike (S) and nucleocapsid (N) protein of SARS-CoV-2 at 180 days after two-dose vaccination were detected. Results: The CoronaVac and Covilo vaccines induced similar antibody responses. Regarding neutralizing antibodies to live SARS-CoV-2, 77.9% of the CoronaVac vaccine recipients and 78.3% of the Covilo vaccine recipients (aged 18-59 years) seroconverted by 28 days after the second vaccine dose. Regarding SARS-CoV-2-specific antibodies, 97.1% of the CoronaVac vaccine recipients and 95.7% of the Covilo vaccine recipients seroconverted by 28 days after the second vaccine dose. The inhibition rates of neutralizing antibody against a pseudovirus of the SARS-CoV-2 Delta variant were significantly lower compared with those against a pseudovirus of wildtype SARS-CoV-2. Associated with participant characteristics and antibody levels, persons in the older age group and with basic disease, especially a chronic respiratory disease, tended to have lower anti-SARS-CoV-2 antibody seroconversion rates. Conclusion: Antibodies that were elicited by these two inactivated COVID-19 vaccines appeared to wane following their peak after the second vaccine dose, but they persisted at detectable levels through 6 months after the second vaccine dose, and the effectiveness of these antibodies against the Delta variant of SARS-CoV-2 was lower than their effectiveness against wildtype SARS-CoV-2, which suggests that attention must be paid to the protective effectiveness, and its persistence, of COVID-19 vaccines on SARS-CoV-2 variants.

2.
Renewable Energy ; 198:1121-1130, 2022.
Article in English | Scopus | ID: covidwho-2015974

ABSTRACT

The COVID-19 pandemic has pushed up the green finance for renewable energy development. Private investment has been recognized as a dominant driver of the renewable energy industry, an essential and critical step in averting greenhouse gas emissions. Nonetheless, despite the increasing pace, private investment in green finance for renewable development is still restricted to several developed nations, where it is crucial. Prior studies have offered some understanding of the complexities and challenges that investment confronts in this industry, which remains underexplored in the case of China. This study employs the ARDL-PMG model used to examine the public listed companies in Shanghai and Shenzhen during China's 2010–2020 period. This research adds to the body of knowledge by rigorously examining the variables on FDI in renewable energy production in China and how these effects differ depending on the source of investment. Some of these factors include the adoption of national renewable energy legislation, the supply of foreign public money, and the broader economic environment. The findings indicate that worldwide financial assistance, legislative support policies, feed-in tariffs, and economic stability are potent drivers of green finance for developing renewable energy investment in China. Further, this research explains that the impacts of private sector investment and entrepreneurial contextual factors on expenditure vary depending on the source of finance, emphasizing the importance of dissecting investment spreads to fully comprehend private investment decisions in green finance for renewable development. © 2022

3.
Frontiers in Immunology ; 13:967716, 2022.
Article in English | MEDLINE | ID: covidwho-2002494

ABSTRACT

Background: The Omicron SARS-CoV-2 variant has spread quickly worldwide due to its effects on virus transmission and vaccine effectiveness. Interferon(IFN) has been shown to have a protective effect against SARS-CoV because of its broad antiviral activity. This study aimed to analyze the treatment effects of IFN alpha-2b spray in virus clearance of the Omicron SARS-CoV-2 variant. Methods: We examined the effectiveness and safety of IFN alpha-2b spray in Shanghai, China, with participants infected with the Omicron SARS-CoV-2 variant in an open, prospective cohort study from April 16th to May 5th, 2022. Results: A total of 871 confirmed patients were enrolled in this study. Four hundred and thirteen patients were allocated to the IFN alpha-2b spray group, and 458 patients were allocated to the control group. The viral shedding time was significantly different between experimental group and control group (11.90 vs.12.58, P <0.05). In the experimental group, the median administration time since the first positive test for SARS-CoV-2 was three days, ranging from 0 to 15 days. There was no obvious adverse effect associated with the spray of IFN alpha-2b. The univariate Cox regression analysis revealed that the administration time since the first positive test <=3 days was a protective factor associated with viral shedding time (HR 0.81 95% CI 0.74-0.87, P <0.05). Subgroup analysis showed that the viral shedding time was 10.41 (4.00-16.00) days in the <=3 days group, which was significantly less than that in the control group (12.58, 95% CI: 7.00-19.15, P <0.0001) and in the >3 days group (13.56, 95%CI: 7.00-22.25, P <0.0001). Conclusions: IFN alpha-2b spray shortened the viral shedding time of the Omicron SARS-CoV-2 variant when administrated within three days since the first positive test for SARS-CoV-2.

4.
Chinese Journal of Microbiology and Immunology (China) ; 42(1):16-22, 2022.
Article in Chinese | EMBASE | ID: covidwho-1928714

ABSTRACT

Objective To detect the serum levels of SARS-CoV-2-specific IgM and IgG antibodies in patients infected with SARS-CoV-2 and recipients of inactivated vaccine in different periods for understanding their variation patterns in vivo. Methods Chemiluminescence immunoassay was used to detect the levels of SARS-CoV-2-specific IgM and IgG antibodies in 144 serum samples of 44 COVID-19 patients, 381 serum samples of 118 asymptomatic infected cases and 398 serum samples of 273 inactivated vaccine recipients collected at different periods. The results were statistically analyzed together with basic characteristics and vaccination status. Results The positive rates of IgM antibody in COVID-19 patients, asymptomatic infected cases and inactivated vaccine recipients were 52. 27% (23 / 44), 23. 73% (28 / 118) and 14. 29% (39 / 273). The positive rate of IgM antibody was higher in COVID-19 patients than in asymptomatic infected cases and vaccine recipients (χ2 = 12. 106, P = 0. 001;χ2 = 34. 755, P<0. 001). The positive rates of IgG antibody in the three populations were 100. 00% (44 / 44), 97. 46% (115 / 118) and 98. 81% (166 / 168), and the differences were not statistically significant (χ2 = 2. 944, P = 0. 229). In COVID-19 patients, the concentration of IgM antibody in <40 years old group was lower than that in ≥40 years old group (Waldχ2 = 6. 609, P = 0. 010), and the concentration of IgG antibody in patients with vaccination was higher than that in patients without vaccination (Waldχ2 = 12. 402,P<0. 001). In asymptomatic infected cases, the concentration of IgG antibody was higher in people with vaccination than in those without vaccination (Waldχ2 = 4. 530, P = 0. 033). In SARS-CoV-2 vaccine recipients, the concentration of IgG antibody in <40 years old group was higher than that in ≥40 years old group (Waldχ2 = 9. 565, P = 0. 002). Dynamic analysis of antibody levels showed that from week 1 to week 9, the concentrations of IgM and IgG antibodies in COVID-19 patients were higher than those in asymptomatic infected cases and vaccine recipients. Conclusions The concentrations of IgM and IgG antibodies in COVID-19 patients were higher than those in asymptomatic infected cases and inactivated vaccine recipients. COVID-19 patients aged ≥40 years had higher level of IgM antibody. COVID-19 patients and asymptomatic infected cases who had received vaccination had higher concentration of IgG antibody. Inactivated vaccine showed good immunogenicity after whole course of immunization, and the IgG antibody level in <40 years old group was higher.

5.
6th IEEE International Conference on Data Science in Cyberspace, DSC 2021 ; : 635-639, 2021.
Article in English | Scopus | ID: covidwho-1831756

ABSTRACT

Advanced Persistent Threat (APT) attack activities with the theme of COVID-19 and vaccine are also growing rapidly. The target of APT attack has gradually expanded from government agencies to vaccine manufacturers, medical industry and so on. What's more, APT groups have a strict organizational structure and professional division of labor and malware delivered by the same APT groups are similar. Classifying malware samples into known APT groups in time can minimize losses as soon as possible and keep relevant industries vigilant. In our paper, we proposed a multi-classification method of APT malware based on Adaboost and LightGBM. We collect real APT malware samples that have been delivered by 12 known APT groups. The API call sequence of each APT malware is obtained through the sandbox. For the relationship between adjacent APIs, we use TF-IDF algorithm combined with bi-gram. Then, Adaboost algorithm is used to select out the important API features, which form the target feature subset. Finally, we use the above subset combined with LightGBM ensemble algorithm to train multiple classifiers, named Ada-LightGBM. The experimental results show that our method is superior to the single Adaboost and LightGBM method. The classifier has good recognition performance for the test samples. © 2021 IEEE.

6.
Blood ; 138:2712, 2021.
Article in English | EMBASE | ID: covidwho-1582150

ABSTRACT

Introduction: Amid the current COVID-19 pandemic, the highest mortality rates are among the elderly and immunocompromised. Multiple myeloma (MM) patients are immunocompromised and often are elderly. Not only do MM patients develop more frequent infections, but it is one of the leading causes of death for these patients. This population develops more severe COVID-19 due to various mechanisms that impair their ability to fight infection. This also reduces their ability to generate immunity from vaccination, as has been demonstrated by their diminished responses to vaccines for various respiratory illnesses. It follows that while phase III trial results for mRNA1273 and BNT162b2 COVID-19 vaccines showed an efficacy of 94-95% against even mild infection with this virus, the efficacy has been shown to be lower among MM patients. We recently evaluated patients' antibody responses to vaccination for COVID-19 by measuring anti-spike IgG levels in patient serum from before vaccination (baseline) and two weeks after dose 2 (D2W2) of vaccination with mRNA-1273 or BNT162b2, and found that most MM patients have impaired responses (Stampfer et al., Leukemia 2021). Patients who received mRNA-1273 vaccine had higher antibody levels than those who were vaccinated with BNT162b2, and specific clinical and myeloma-related characteristics predicted vaccine responsiveness. In the current study, we are monitoring anti-spike IgG antibody levels at Dose 2 Week 8 (D2W8) and Dose 2 Week 16 (D2W16) post-mRNA vaccination among these patients and in age-matched healthy controls to investigate antibody decay. Methods: Participants in the trial included MM patients (n=91) at the Berenson Cancer Center, and age-matched healthy controls (n=27). Healthy subjects were not known to be immunocompromised or currently receiving immunosuppressive therapy. Vaccination was done outside of the clinic and subjects provided copies of their CDC-issued COVID-19 vaccination cards to confirm dosing dates. Sera from vaccinated individuals were drawn at baseline (0-60 days prior to first vaccine dose) and at intervals following their second dose (14-21, 56-70, and 112-126 days post-vaccination). Background levels were determined from the clinic's serum bank of healthy subjects drawn pre-April 2019. Using an ELISA-based assay that detects IgG antibodies to SARS-CoV-2 spike protein, we determined Anti-SARS-CoV-2 spike ectodomain serum antibody levels and quantified them in IU/mL based on the WHO International Standard 20/136. Results: We analyzed the patient and control populations, and specifically for those classified as responders from our original published study (D2W2 >50 IU/mL). All controls but only 70% of patients (64/91) were classified as responders, so this responder-specific analysis was only relevant for patients. There was a significant decline in anti-SARS-CoV-2 spike antibodies from D2W2 to D2W8 for both patients and controls;D2W16 results are pending. Median values dropped from 283.1 IU/mL to 90.9 IU/mL among patients, and 893.6 IU/mL to 354.4 IU/mL among controls. Median antibody levels among patients classified as responders dropped from 482.9 IU/mL to 145.5 IU/mL (p <0.0001). We also found that the D2W8 value for patients was significantly lower than that of controls (90.9 IU/mL vs 354.4 IU/mL, p<0.0001), as well as among the responder group (145.5 IU/mL vs 354.4 IU/mL, p=0.0005). A cutoff of <147 IU/mL has previously been associated with an increased risk for breakthrough infections. Spike antibody levels of 50% of patients who responded and 64.8% of all patients were <147 IU/mL at D2W8, whereas only 7.4% of controls were <147 IU/mL (p<0.0001). Conclusions: The markedly lower anti-spike antibody levels among MM patients compared to healthy controls at week 8 post-vaccination indicate that they remain at high risk for breakthrough infections. Combined with their rapid decline in anti-spike antibody levels over only a 6-week period, this indicates that even MM patients who responded initially to vaccination are likely to require boosters sooner tha healthy individuals. This immunocompromised population remains at high risk even following vaccination and should continue to maintain social distancing precautions during periods of high local SARS-CoV-2 transmission. Disclosures: No relevant conflicts of interest to declare.

7.
Management Science ; : 31, 2021.
Article in English | Web of Science | ID: covidwho-1486635

ABSTRACT

We formulate a dynamic no-arbitrage asset pricing model for equities and corporate bonds, featuring time variation in both risk aversion and economic uncertainty. The joint dynamics among cash flows, macroeconomic fundamentals, and risk aversion accommodate both heteroskedasticity and non-Gaussianity. The model delivers measures of risk aversion and uncertainty at the daily frequency. We verify that equity variance risk premiums are very informative about risk aversion, whereas credit spreads and corporate bond volatility are highly correlated with economic uncertainty. Our model-implied risk premiums outperform standard instruments for predicting asset excess returns. Risk aversion is substantially correlated with consumer confidence measures and in early 2020 reacted more strongly to new COVID cases than did an uncertainty proxy.

8.
Procedia Comput. Sci. ; 183:768-775, 2021.
Article in English | Scopus | ID: covidwho-1213475

ABSTRACT

In the fight against the Covid-19, social distancing has proven to be a very effective measure to mitigate the spread of the disease. As resumption of work, production and classes accelerates, it is necessary to limit people's social distance to reduce the rate of the virus spread. To solve this problem, a method for monitoring social distancing based on SSD object detection technology is proposed in this study. This method utilizes SSD300 model to detect people in a video or picture, and labels a Red Line as warning on the people whose distances are less than the default one, implementing real-time social distancing monitoring, and the mAP reaches 88.44%. © 2021 The Authors. Published by Elsevier B.V.

9.
Proc. - IEEE Int. Conf. Bioinform. Biomed., BIBM ; : 2005-2008, 2020.
Article in English | Scopus | ID: covidwho-1075727

ABSTRACT

Background and Objective: The Coronavirus Disease 2019 pandemic situation is remaining severe worldwide. A single outbreak data source is not adequate for comprehensive analyses of the response to the pandemic. Such analyses need to seek proper integration of epidemic data for subsequent statistical analyses. Methods: 1) Considering reputations of publishers, activities, public users' accessibility, and retrievable historical data among several platforms, the World Health Organization (WHO), the US Centers for Disease Control (CDC), and Baidu's Real-time Epidemics (BRE) websites were selected as our data sources. 2) Data for 32 weeks until August 15th, 2020, were followed, including the US cumulative confirmed cases (CCCs), cumulative death cases (CDCs), cumulative discharged or cured cases (CD\vert CCs), daily new infective confirmed cases (DNCCs), and daily new death cases (DNDCs). 3) Estimators for the weekly current active infected confirm cases (CACs) and the weekly COVID19 fatal rate in the US hospitals (WFRUSH) were derived. Graphic display modules demonstrated the risks associated with demographic data. Results: 1) CCCs reached 5,285,546 cases in the US on August 15th, 2020, which initially climbed from the 9th-11th week;the CDCs were 167,546. The fatality rate initially climbed from the 12th-13th week, but fast turned over to decrease from the 18th week, then gradually flattened out near 3.17% till the mid of August 2020. 2) The WFRUSH first rose sharply at the 10th-11th week and started to decline in the 12th week, although there was a repeated smaller fluctuation in the 13th-14th week, during the generally downward process. 3) The US demographic characteristics and CDCs showed that the proportion of fatal cases in the senior Americans (age group over 65) accounted was 78.8%, about 4 (3.83) times the proportions of the other age groups. Supposed the death cases of seniors, directly caused by the COVID-19 rather than caused by the fundamental diseases, the \gamma value of the seniors, a ratio between the senior CDCs proportion over the senior population proportion was 4.81. Such a \gamma value for seniors, indicated a much higher fatality risk than other age groups. Conclusion: Integrative capture data from the publicly web-published COVID-19 statistics helps extend analyzable data and estimate or derive new-useful indicators CACs, WFRUSH, and \gamma value for the demographic group. As of the including the working population age of over 45, would have a much higher fatality rate than younger ages. It seemed necessary to study further if these death were caused directly by the COVID-19. Additionally, the African Americans, and male Americans, had relatively higher fatality rates. These high risks require more attention to strengthening health prevention;including the working-age population, even although the WFRUSH as a more appropriate and vital indication becomes stable to a low level after July 2020, meaning the clinical interventions and treatments were improved, or the virus fatality power was declined. © 2020 IEEE.

10.
Zhonghua Wei Chang Wai Ke Za Zhi ; 24(4): 359-365, 2021 Apr 25.
Article in Chinese | MEDLINE | ID: covidwho-827753

ABSTRACT

Objective: Pelvic high-resolution magnetic resonance imaging (MRI) has now become a standard method for evaluating the efficacy of neoadjuvant treatment for locally advanced rectal cancer (LARC). However, this traditional morphological qualitative assessment method based on T2-weighted imaging (T2WI) is not effective in predicting pathological complete remission (pCR). The purpose of this study is to investigate whether combining the magnetic resonance tumor regression grade (mrTRG) with apparent diffusion coefficient (ADC) can improve diagnostic value for pCR after preoperative neoadjuvant chemoradiotherapy (nCRT) of LARC. Methods: This was a diagnostic study. Clinicopathological data of 134 LARC patients who received nCRT and radical surgery in the First Affiliated Hospital of Kunming Medical University from January 2017 to December 2019 were retrospectively analyzed. All the patients underwent MRI which included T2WI and DWI sequences before and 8 weeks after nCRT. Two radiologists independently drew ROIs on T2WI and DWI to estimate mrTRG stage and calculate the mean ADC value. Receiver operating characteristics (ROC) method was applied to evaluate the predict value of mrTRG combined with mean ADC value for pCR. Results: Of 134 LARC patients, 85 were male and 49 were female with median age of 58 (28-82) years. After nCRT, MRI suggested 21 patients (15.7%) had clinical complete remission (cCR), e.g. mrTRG stage 1-2. Postoperative pathology revealed 31 (23.1%) patients had pCR. The evaluations of mrTRG and ADC value by the two readers were highly consistent, and the intra-group correlation coefficients were 0.83 (95% CI: 0.703-0.881) and 0.96 (95% CI: 0.989-0.996), respectively. There was a negative correlation between mrTRG and pCR (r(s)=-0.505, P<0.01), and a positive correlation between mean ADC value and pCR (r(s)=0.693, P<0.01). The ROC curve showed that mrTRG alone had a medium predictive value for pCR, with an area under the curve (AUC) of 0.832 (95% CI: 0.743-0.921); the mean ADC value had a higher predictive value for pCR, with AUC of 0.906 (95% CI: 0.869-0.962). The predictive value of the combined model of mrTRG and ADC value for pCR was significantly better than that of mrTRG alone (P=0.015), and the AUC was 0.908 (95% CI: 0.849-0.968). Conclusion: Both mrTRG and mean ADC value can be non-invasive methods to predict the efficacy of nCRT for LARC. Combining the mean ADC value with mrTRG can result in better pCR prediction.


Subject(s)
Neoadjuvant Therapy , Rectal Neoplasms , Aged , Aged, 80 and over , Chemoradiotherapy , Diffusion Magnetic Resonance Imaging , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Rectal Neoplasms/drug therapy , Rectal Neoplasms/therapy , Retrospective Studies , Treatment Outcome
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