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1.
Sustainability ; 15(9):7560, 2023.
Article in English | ProQuest Central | ID: covidwho-2312618

ABSTRACT

Financial distress is a research topic in finance that has attracted attention from academia following past financial crises. Although previous studies associate financial distress with several elements, the relationship between distress and ESG has not been broadly explored. This paper investigates these issues by elaborating a Dynamic Network DEA model to address the underlying connections between accounting and financial indicators. Thus, a model that includes profit and loss, balance sheet, and capital and operating expenditures indicators is demonstrated under the dynamic network structure to compute financial-distress efficiency scores. Then, the impact of carryovers is considered for the accurate calculation of efficiency scores for the three substructures. The influence of contextual variables, such as socioeconomic and macroeconomic variables, and whether the firm owns an ESG Risk Score or not, is assessed through a stochastic non-linear model that combines three distinct regression types: Simplex, Tobit, and Beta. The results indicate that firms that hold an ESG Risk Score are less prone to be in financial distress, and Governance Score is negatively associated with financial distress efficiency.

2.
Health Care Manag Sci ; 2023 May 09.
Article in English | MEDLINE | ID: covidwho-2316305

ABSTRACT

The coronavirus infection COVID-19 killed millions of people around the world in 2019-2022. Hospitals were in the forefront in the battle against the pandemic. This paper proposes a novel approach to assess the effectiveness of hospitals in saving lives. We empirically estimate the production function of COVID-19 deaths among hospital inpatients, applying Heckman's two-stage approach to correct for the bias caused by a large number of zero-valued observations. We subsequently assess performance of hospitals based on regression residuals, incorporating contextual variables to convex quantile regression. Data of 187 hospitals in England over a 35-week period from April to December 2020 is divided in two sub-periods to compare the structural differences between the first and second waves of the pandemic. The results indicate significant performance improvement during the first wave, however, learning by doing was offset by the new mutated virus straits during the second wave. While the elderly patients were at significantly higher risk during the first wave, their expected mortality rate did not significantly differ from that of the general population during the second wave. Our most important empirical finding concerns large and systematic performance differences between individual hospitals: larger units proved more effective in saving lives, and hospitals in London had a lower mortality rate than the national average.

3.
Sensors (Basel) ; 23(8)2023 Apr 07.
Article in English | MEDLINE | ID: covidwho-2306248

ABSTRACT

Frequency estimation plays a critical role in vital sign monitoring. Methods based on Fourier transform and eigen-analysis are commonly adopted techniques for frequency estimation. Because of the nonstationary and time-varying characteristics of physiological processes, time-frequency analysis (TFA) is a feasible way to perform biomedical signal analysis. Among miscellaneous approaches, Hilbert-Huang transform (HHT) has been demonstrated to be a potential tool in biomedical applications. However, the problems of mode mixing, unnecessary redundant decomposition and boundary effect are the common deficits that occur during the procedure of empirical mode decomposition (EMD) or ensemble empirical mode decomposition (EEMD). The Gaussian average filtering decomposition (GAFD) technique has been shown to be appropriate in several biomedical scenarios and can be an alternative to EMD and EEMD. This research proposes the combination of GAFD and Hilbert transform that is termed the Hilbert-Gauss transform (HGT) to overcome the conventional drawbacks of HHT in TFA and frequency estimation. This new method is verified to be effective for the estimation of respiratory rate (RR) in finger photoplethysmography (PPG), wrist PPG and seismocardiogram (SCG). Compared with the ground truth values, the estimated RRs are evaluated to be of excellent reliability by intraclass correlation coefficient (ICC) and to be of high agreement by Bland-Altman analysis.


Subject(s)
Algorithms , Respiratory Rate , Reproducibility of Results , Photoplethysmography/methods , Normal Distribution , Signal Processing, Computer-Assisted
4.
Pharmaceutics ; 15(3)2023 Mar 12.
Article in English | MEDLINE | ID: covidwho-2272615

ABSTRACT

The COVID-19 pandemic has brought about unprecedented medical and healthcare challenges worldwide. With the continual emergence and spread of new COVID-19 variants, four drug compound libraries were interrogated for their antiviral activities against SARS-CoV-2. Here, we show that the drug screen has resulted in 121 promising anti-SARS-CoV-2 compounds, of which seven were further shortlisted for hit validation: citicoline, pravastatin sodium, tenofovir alafenamide, imatinib mesylate, calcitriol, dexlansoprazole, and prochlorperazine dimaleate. In particular, the active form of vitamin D, calcitriol, exhibits strong potency against SARS-CoV-2 on cell-based assays and is shown to work by modulating the vitamin D receptor pathway to increase antimicrobial peptide cathelicidin expression. However, the weight, survival rate, physiological conditions, histological scoring, and virus titre between SARS-CoV-2 infected K18-hACE2 mice pre-treated or post-treated with calcitriol were negligible, indicating that the differential effects of calcitriol may be due to differences in vitamin D metabolism in mice and warrants future investigation using other animal models.

5.
J Med Virol ; : e28258, 2022 Oct 27.
Article in English | MEDLINE | ID: covidwho-2244711

ABSTRACT

Waning antibody levels against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the emergence of variants of concern highlight the need for booster vaccinations. This is particularly important for the elderly population, who are at a higher risk of developing severe coronavirus disease 2019 (COVID-19) disease. While studies have shown increased antibody responses following booster vaccination, understanding the changes in T and B cell compartments induced by a third vaccine dose remains limited. We analyzed the humoral and cellular responses in subjects who received either a homologous messenger RNA(mRNA) booster vaccine (BNT162b2 + BNT162b2 + BNT162b2; ''BBB") or a heterologous mRNA booster vaccine (BNT162b2 + BNT162b2 + mRNA-1273; ''BBM") at Day 0 (prebooster), Day 7, and Day 28 (postbooster). Compared with BBB, elderly individuals (≥60 years old) who received the BBM vaccination regimen display higher levels of neutralizing antibodies against the Wuhan and Delta strains along with a higher boost in immunoglobulin G memory B cells, particularly against the Omicron variant. Circulating T helper type 1(Th1), Th2, Th17, and T follicular helper responses were also increased in elderly individuals given the BBM regimen. While mRNA vaccines increase antibody, T cell, and B cell responses against SARS-CoV-2 1 month after receiving the third dose booster, the efficacy of the booster vaccine strategies may vary depending on age group and regimen combination.

6.
J Med Virol ; 2022 Sep 19.
Article in English | MEDLINE | ID: covidwho-2236120

ABSTRACT

Messenger RNA (mRNA) vaccines are promising alternatives to conventional vaccines in many aspects. We previously developed a lipopolyplex (LPP)-based mRNA vaccine (SW0123) that demonstrated robust immunogenicity and strong protective capacity against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in mice and rhesus macaques. However, the immune profiles and mechanisms of pulmonary protection induced by SW0123 remain unclear. Through high-resolution single-cell analysis, we found that SW0123 vaccination effectively suppressed SARS-CoV-2-induced inflammatory responses by inhibiting the recruitment of proinflammatory macrophages and increasing the frequency of polymorphonuclear myeloid-derived suppressor cells. In addition, the apoptotic process in both lung epithelial and endothelial cells was significantly inhibited, which was proposed to be one major mechanism contributing to vaccine-induced lung protection. Cell-cell interaction in the lung compartment was also altered by vaccination. These data collectively unravel the mechanisms by which the SW0123 protects against lung damage caused by SARS-CoV-2 infection.

7.
Sustainability ; 14(17):10664, 2022.
Article in English | MDPI | ID: covidwho-2006186

ABSTRACT

(1) Background: The teaching profession has become more challenging due to the increased use of information technology, which potentially increases psychological distress among teachers. This study aimed to determine the prevalence of depression, anxiety, and stress among school teachers in Malaysia during the period of the COVID-19 pandemic and its associated sociodemographic factors. (2) Methods: A cross-sectional study was conducted among primary and secondary school teachers in Malaysia. A validated DASS-21 questionnaire was used for mental health screening, and the study was conducted online during the pandemic period. (3) Results: The percentages of respondents with mild, moderate, severe, and extremely severe depression were 12%, 9.7%, 4.7%, and 3.1%, respectively. Those with mild, moderate, severe, and extremely severe anxiety accounted for 11.5%, 12.3%, 6.3%, and 6%, respectively. Those with mild, moderate, severe, and very severe stress accounted for 12.8%, 12%, 5.3%, and 2.5%, respectively. Perceived overworking was significantly greater during the pandemic compared to before the pandemic. Significant experience in teaching, and less perceived overworking before and during the pandemic were associated with better mental health. (4) Conclusions: Periodic mental health screening for teachers may be beneficial in preventing mental health disorders and improving the quality of student education. A full assessment and innovation of the curriculum and workload should be implemented.

8.
Clin Transl Immunology ; 11(8): e1403, 2022.
Article in English | MEDLINE | ID: covidwho-2003593

ABSTRACT

Objective: Despite the high vaccine efficacy of mRNA COVID-19 vaccines, there are individuals who developed excessive reactogenic and/or allergic responses after the first mRNA dose and were considered ineligible for further mRNA doses. CoronaVac, an inactivated SARS-CoV-2 vaccine, is recommended in Singapore as an alternative. Methods: Individuals, ineligible for further mRNA vaccines (BNT162b2 or mRNA-1273) because of excessive reactive responses to prime mRNA vaccination, were recruited and offered two doses of CoronaVac as booster vaccination 38-224 days post their mRNA vaccine dose. Individuals who did not develop any excessive reactive responses after the prime mRNA vaccination were also recruited and given another mRNA vaccine as booster vaccination. Blood samples were collected at days 0, 21 and 90 post first CoronaVac dose and mRNA dose, respectively, for analysis. Results: We showed that two CoronaVac booster doses induced specific immunity in these mRNA vaccine-primed individuals. Although the spike-specific antibody response was lower, their memory B cell response against the receptor-binding domain (RBD) of the spike protein was similar, compared with individuals who received two BNT162b2 injections. The spike-specific memory T cell response also increased following CoronaVac booster doses. However, specific immunity against the Omicron variant was low, similar to individuals with two BNT162b2 doses. Conclusion: Our findings showed that while mRNA vaccine-primed individuals can opt for two subsequent doses of CoronaVac, an additional dose may be necessary to achieve protection, especially against newly emerging immune escape variants such as Omicron.

9.
Ocean & Coastal Management ; 225:106230, 2022.
Article in English | ScienceDirect | ID: covidwho-1851895

ABSTRACT

Global maritime supply chain (MSC) faces increasing risks of uncertainty in the post COVID-19 era, ports disruptions and congestion are becoming common. To ensure high reliability of container shipping network, this paper study on the issue of locating hub ports and allocating non-hub ports (spokes) to hubs, meanwhile backup hub ports. An extended container shipping hub-and-spoke network design problem (HSN) is investigated, considering the failure and congestion of hubs, a 0–1 nonlinear programming model is developed for minimizing the transportation cost. Furthermore, we simulate container shipping network using Asia-Europe trade data, and propose the approach of particle swarm optimization (PSO) to solve the model. The experimental results show that path replacement cost and congestion cost affect the network design to a great extent, and backup hub ports could improve the reliability of global container shipping networks for capacity scheduling and allocation. This study can provide certain useful managerial insights for the liner company's daily operation, and design flexible container shipping HSN to ensure maximum efficiency after the COVID-19 irruption.

10.
Annu Rev Biochem ; 91: 1-32, 2022 06 21.
Article in English | MEDLINE | ID: covidwho-1759478

ABSTRACT

Cryo-electron microscopy (cryo-EM) continues its remarkable growth as a method for visualizing biological objects, which has been driven by advances across the entire pipeline. Developments in both single-particle analysis and in situ tomography have enabled more structures to be imaged and determined to better resolutions, at faster speeds, and with more scientists having improved access. This review highlights recent advances at each stageof the cryo-EM pipeline and provides examples of how these techniques have been used to investigate real-world problems, including antibody development against the SARS-CoV-2 spike during the recent COVID-19 pandemic.


Subject(s)
COVID-19 , Pandemics , Cryoelectron Microscopy/methods , Humans , SARS-CoV-2 , Single Molecule Imaging
11.
Comput Ind Eng ; 161: 107591, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1347536

ABSTRACT

Governments have been challenged to provide timely medical care to face the COVID-19 pandemic. The aim of this research is to propose a novel inventory pooling model to help determine order sizes and safety inventories in local hospital warehouses. The current study attempts to portray the availability of pharmaceutical items in public hospitals facing COVID-19 challenges. Different from previous studies, this research builds upon the consecrated theory of inventory pooling, extending it to pandemic circumstances where the intractability of kurtosis and skewness in inventory models are critical issues for making sure that medicines have high availability at a low cost. These effects on the total cost of inventory are explored and compared to a supply system with no consolidation. A continuous-review model is assumed with allocation rules for centralization and regular transshipment given different skewness and kurtosis structures for the demand, describing them by the copula method. This method models a multivariate demand considering that the marginal distributions of the demand can be specified by the Generalized Additive Model for Location, Scale and Shape, which offers advantages to model demands considering virtually any marginal statistical distribution. Numerical simulations and an illustrative example show that distributions of demands with more negative skewness and high kurtosis favor to a greater extent obtaining lower total costs with regular supply transshipment systems. Our study points out important considerations for supply chain decision makers when having demands with skewness and kurtosis patterns.

12.
Nat Commun ; 12(1): 3661, 2021 06 16.
Article in English | MEDLINE | ID: covidwho-1275912

ABSTRACT

SARS-CoV-2, the virus responsible for COVID-19, has caused a global pandemic. Antibodies can be powerful biotherapeutics to fight viral infections. Here, we use the human apoferritin protomer as a modular subunit to drive oligomerization of antibody fragments and transform antibodies targeting SARS-CoV-2 into exceptionally potent neutralizers. Using this platform, half-maximal inhibitory concentration (IC50) values as low as 9 × 10-14 M are achieved as a result of up to 10,000-fold potency enhancements compared to corresponding IgGs. Combination of three different antibody specificities and the fragment crystallizable (Fc) domain on a single multivalent molecule conferred the ability to overcome viral sequence variability together with outstanding potency and IgG-like bioavailability. The MULTi-specific, multi-Affinity antiBODY (Multabody or MB) platform thus uniquely leverages binding avidity together with multi-specificity to deliver ultrapotent and broad neutralizers against SARS-CoV-2. The modularity of the platform also makes it relevant for rapid evaluation against other infectious diseases of global health importance. Neutralizing antibodies are a promising therapeutic for SARS-CoV-2.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antibodies, Neutralizing/immunology , Antibodies, Viral/chemistry , SARS-CoV-2/immunology , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/genetics , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/chemistry , Antibodies, Viral/immunology , Antibody Specificity , Apoferritins/chemistry , Biological Availability , Epitope Mapping , Humans , Immunoglobulin G/immunology , Male , Mice, Inbred BALB C , Mice, Inbred C57BL , Protein Engineering/methods , Protein Subunits/chemistry , Spike Glycoprotein, Coronavirus/immunology , Tissue Distribution
13.
Virus Res ; 286: 198074, 2020 09.
Article in English | MEDLINE | ID: covidwho-611212

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel human coronavirus causing the pandemic of severe pneumonia (Coronavirus Disease 2019, COVID-19). SARS-CoV-2 is highly pathogenic in human, having posed immeasurable public health challenges to the world. Innate immune response is critical for the host defense against viral infection and the dysregulation of the host innate immune responses probably aggravates SARS-CoV-2 infection, contributing to the high morbidity and lethality of COVID-19. It has been reported that some coronavirus proteins play an important role in modulating innate immunity of the host, but few studies have been conducted on SARS-CoV-2. In this study, we screened the viral proteins of SARS-CoV-2 and found that the viral ORF6, ORF8 and nucleocapsid proteins were potential inhibitors of type I interferon signaling pathway, a key component for antiviral response of host innate immune. All the three proteins showed strong inhibition on type I interferon (IFN-ß) and NF-κB-responsive promoter, further examination revealed that these proteins were able to inhibit the interferon-stimulated response element (ISRE) after infection with Sendai virus, while only ORF6 and ORF8 proteins were able to inhibit the ISRE after treatment with interferon beta. These findings would be helpful for the further study of the detailed signaling pathway and unveil the key molecular player that may be targeted.


Subject(s)
Betacoronavirus/genetics , Host-Pathogen Interactions/genetics , Interferon-beta/genetics , NF-kappa B/genetics , Nucleocapsid Proteins/genetics , Viral Proteins/genetics , Betacoronavirus/immunology , Coronavirus Nucleocapsid Proteins , Gene Expression Regulation , Genes, Reporter , HEK293 Cells , Host-Pathogen Interactions/immunology , Humans , Immunity, Innate , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/immunology , Interferon-beta/immunology , Luciferases/genetics , Luciferases/metabolism , NF-kappa B/immunology , Nucleocapsid Proteins/immunology , Phosphoproteins , Plasmids/chemistry , Plasmids/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Response Elements , SARS-CoV-2 , Sendai virus/genetics , Sendai virus/immunology , Signal Transduction , Transfection/methods , Viral Proteins/immunology
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