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1.
Applied Economics Letters ; 30(12):1685-1691, 2023.
Article in English | ProQuest Central | ID: covidwho-20238811

ABSTRACT

Bitcoin market had a significant momentum phenomenon before the launch of Futures, and then it turned into an insignificant reversal effect. After Covid-19 appeared, the momentum effect and reversal effect disappeared. The advent of bitcoin futures has increased how investors respond to information. With the outbreak of COVID-19, investor interest in Bitcoin as a safe-haven asset has increased the effectiveness of the price. We estimate the speed of signal diffusion in the bitcoin market, and the results support that effective response to information is the essential mechanism for the disappearance of momentum effect.

2.
Int J Intercult Relat ; 96: 101843, 2023 Sep.
Article in English | MEDLINE | ID: covidwho-20239243

ABSTRACT

We present a framework for studying the spillover effect of negative foreign COVID-19 news on attitudes towards immigration. Our framework proposes that exposure to negative COVID-19 news from foreign countries can activate negative associations with foreigners, reduce positive attitudes towards them, and increase perceived threat, ultimately leading to decreased support for immigration. We conducted three studies to test this framework. Study 1 found that exposure to negative COVID-19 news about a foreign country increased negative valence associations with that country. Study 2 showed that exposure to more negative COVID-19 news about foreign countries was associated with lower acceptance of immigration policies in real life. Study 3 replicated the spillover effect of negative news exposure using a scenario manipulation. The effects of negative news exposure on immigration policy acceptance in both Studies 2 and 3 were mediated by changes in foreigner attitudes and intergroup threat. Our results demonstrate the important spillover effect of negative foreign COVID-19 news exposure on immigration attitudes and highlight the association perspective as a foundation for understanding attitude changes during the COVID-19 pandemic.

3.
ACS Sens ; 8(5): 2096-2104, 2023 05 26.
Article in English | MEDLINE | ID: covidwho-2327385

ABSTRACT

The large-scale pandemic and fast evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have triggered an urgent need for an efficient and sensitive on-site nucleic acid testing method with single-nucleotide polymorphism (SNP) identification capability. Here, we report a multiplexed electrical detection assay based on a paperclip-shaped nucleic acid probe (PNprobe) functionalized field-effect transistor (FET) biosensor for highly sensitive and specific detection and discrimination of SARS-CoV-2 variants. The three-stem structure of the PNprobe significantly amplifies the thermodynamic stability difference between variant RNAs that differ in a single-nucleotide mutation. With the assistance of combinatorial FET detection channels, the assay realizes simultaneously the detection and identification of key mutations of seven SARS-CoV-2 variants, including nucleotide substitutions and deletions at single-nucleotide resolution within 15 min. For 70 simulated throat swab samples, the multiplexed electrical detection assay shows an identification accuracy of 97.1% for the discrimination of SARS-CoV-2 variants. Our designed multiplexed electrical detection assay with SNP identification capability provides an efficient tool to achieve scalable pandemic screening.


Subject(s)
COVID-19 , Humans , COVID-19/diagnosis , Polymorphism, Single Nucleotide , SARS-CoV-2/genetics , Nucleic Acid Probes , Nucleotides
4.
Applied Economics ; 55(17):1972-1989, 2023.
Article in English | ProQuest Central | ID: covidwho-2289000

ABSTRACT

To understand the effect of liquidity on asset pricing, this study constructs a boundedly rational asset pricing model, introducing market liquidity and heterogeneous beliefs. Based on our model, we conduct empirical tests using the S&P 500 index from 1991 to 2021 and the CSI 500 index from 2007 to 2021. We find that market liquidity significantly influences investors' expectations and belief switching. When market liquidity is scarce, fundamentalists in both markets expect the price to converge more quickly to its fundamental value, whereas chartists perceive that the price deviates from its fundamental value less rapidly. Lack of liquidity mitigates the investors' original switching strategy, resulting in positive feedback as a net effect. Moreover, the S&P 500 index is efficient, whereas the CSI 500 index is slightly undervalued in the long run. Both markets exhibit large fluctuations and inefficiency during short periods such as the 2008 financial crisis and COVID-19 pandemic. As such, safeguards should be implemented against sudden shocks and the resulting price deviation and market inefficiency.

6.
Mediators Inflamm ; 2022: 7138756, 2022.
Article in English | MEDLINE | ID: covidwho-2001956

ABSTRACT

Resveratrol is a naturally occurring stilbene phytoalexin phenolic compound, which has been extensively studied on its biological activity. It has been widely accepted that resveratrol possesses anti-inflammatory and antiviral activities. In this review, we summarize the anti-inflammatory dosages and mechanism and antiviral mechanism of resveratrol. Since viral infections are often accompanied by inflammation, we propose that the NF-κB signaling pathway is a key and common molecular mechanism of resveratrol to exert anti-inflammatory and antiviral effects. For future studies, we believe that resveratrol's anti-inflammatory and antiviral mechanisms can consider the upstream signaling molecules of the NF-κB signaling pathway. For resveratrol antivirus, future studies can be conducted on the interaction of resveratrol with key proteins or important enzymes of the virus. In addition, we also think that the clinical application of resveratrol is very important. In short, resveratrol is a promising anti-inflammatory and antiviral drug, and research on it needs to be expanded.


Subject(s)
NF-kappa B , Stilbenes , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , NF-kappa B/metabolism , Resveratrol , Stilbenes/pharmacology , Stilbenes/therapeutic use
7.
Nurse Educ Pract ; 63: 103354, 2022 Aug.
Article in English | MEDLINE | ID: covidwho-2000636

ABSTRACT

AIM: The primary goal of this analysis is to determine the effectiveness of blended learning versus traditional face-to-face teaching in nursing education from the three aspects of knowledge, skills and satisfaction. BACKGROUND: With the rapid development of health care, traditional teaching has been unable to meet the learning needs of nursing education. With the development of Internet technology, blended learning seems to be a new available choice to solve the current predicament. However, the effectiveness of blended learning is still controversial. In addition, most studies have primarily evaluated the teaching effect unilaterally. DESIGN: Systematic review and meta-analysis. METHODS: We searched PubMed, Embase, Web of Science, CINAHL and the Cochrane Library for publications in English from inception to April 2021. Two researchers independently screened the eligibility of each publication and extracted the data. The Cochrane risk-of-bias tool and the MINORS (methodological items for non-randomized studies) were used to evaluate the quality of the studies. The statistical heterogeneity was analyzed by the meta-regression and subgroup analysis. Publication bias was assessed by Egger's test. RESULTS: The search strategy identified a total of 3682 potentially relevant articles. We finally included 13 randomized controlled trials (RCTs) and 12 quasi-experimental studies (QRs), with a total of 2706 nursing students. The meta-analysis results showed that blended learning is more effective than traditional teaching in terms of knowledge, skill performance and learning satisfaction (SMD=0.64, z = 3.237, p = 0.001; SMD = 0.37, z = 2.58, p = 0.010; SMD = 0.32, z = 2.347, p = 0.019). Egger's test showed no significant publication bias. In addition, sensitivity analysis suggested that the results are relatively reliable. Through subgroup analysis and meta regression, we found that although the heterogeneity could not be significantly reduced or eliminated, the publication year, the study design and the duration of the intervention time and the number of items in the intervention may be the potential factors affecting heterogeneity of knowledge and learning satisfaction. CONCLUSIONS: The research results showed that blended learning may be an effective teaching strategy and appears to have excellent long-term developmental potential. Although its initial construction may require specific investment to improve the teaching resources and standardize the design of blended learning, in the long term, this new teaching strategy can not only improve nursing students' professional ability and learning satisfaction but also save nursing education resources to promote the balanced development of nursing education. The results of this study can lay a foundation for establishing standardized blended teaching strategies and evaluation indicators in the future.


Subject(s)
Education, Distance , Education, Nursing , Students, Nursing , Clinical Competence , Education, Distance/methods , Education, Nursing/methods , Humans , Learning , Teaching
8.
Axioms ; 11(8):415, 2022.
Article in English | MDPI | ID: covidwho-1997504

ABSTRACT

A monetary model is established to introduce that bitcoin does have the characteristics of a price rise when the economic situation is terrible under high risk aversion. At this time, Bitcoin has the property of a safe-haven asset, and when economic conditions are good and risk aversion is low, Bitcoin has a pro-cyclical nature. At this time, Bitcoin has a stronger property as a medium of exchange. To show the movement law of the bitcoin price, we make a logarithmic linearization of the model and simulation, and the result is consistent with the theoretical analysis. To better understand the role of bitcoin in the real economy, several standard portfolio models are used to measure the similarities and differences between gold and bitcoin in an investment portfolio. After the outbreak of COVID-19, bitcoin has shown stronger safe-haven asset properties.

10.
Int J Mol Sci ; 23(9)2022 Apr 27.
Article in English | MEDLINE | ID: covidwho-1847340

ABSTRACT

In this study, humidified air dielectric barrier discharge (DBD) plasma was used to inactivate Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and bacteriophages in biofilms containing DNA, NaCl, carbohydrates, and proteins. The humidified DBD plasma was very effective in the inactivation of microbes in the (≤1.0 µm) biofilms. The number of surviving E. coli, S. aureus, and bacteriophages in the biofilms was strongly dependent on the constituent and thickness of the biofilms and was greatly reduced when the plasma treatment time increased from 5 s to 150 s. Our analysis shows that the UV irradiation was not responsible for the inactivation of microbes in biofilms. The short-lived RONS generated in the humidified air DBD plasma were not directly involved in the inactivation process; however, they recombined or reacted with other species to generate the long-lived RONS. Long-lived RONS diffused into the biofilms to generate very active species, such as ONOOH and OH. This study indicates that the geminated NO2 and OH pair formed due to the homolysis of ONOOH can cause the synergistic oxidation of various organic molecules in the aqueous solution. Proteins in the biofilm were highly resistant to the inactivation of microbes in biofilms, which is presumably due to the existence of the unstable functional groups in the proteins. The unsaturated fatty acids, cysteine-rich proteins, and sulfur-methyl thioether groups in the proteins were easily oxidized by the geminated NO2 and OH pair.


Subject(s)
Bacteriophages , Escherichia coli Infections , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Biofilms , Escherichia coli/physiology , Humans , Nitrogen Dioxide , Staphylococcus aureus/physiology
11.
Front Vet Sci ; 9: 820625, 2022.
Article in English | MEDLINE | ID: covidwho-1809643

ABSTRACT

Infectious bronchitis virus (IBV) is the first coronavirus discovered in the world, which is also the prototype of gamma-coronaviruses. Nowadays, IBV is widespread all over the world and has become one of the causative agent causing severe economic losses in poultry industry. Generally, it is believed that the viral replication and immune evasion functions of IBV were modulated by non-structural and accessory proteins, which were also considered as the causes for its pathogenicity. In this study, we summarized the current knowledge about the immune evasion functions of IBV non-structural and accessory proteins. Some non-structural proteins such as nsp2, nsp3, and nsp15 have been shown to antagonize the host innate immune response. Also, nsp7 and nsp16 can block the antigen presentation to inhibit the adapted immune response. In addition, nsp13, nsp14, and nsp16 are participating in the formation of viral mRNA cap to limit the recognition by innate immune system. In conclusion, it is of vital importance to understand the immune evasion functions of IBV non-structural and accessory proteins, which could help us to further explore the pathogenesis of IBV and provide new horizons for the prevention and treatment of IBV in the future.

12.
Vet Microbiol ; 264: 109299, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1559479

ABSTRACT

Porcine deltacoronavirus (PDCoV) is an emerging porcine enteric coronavirus that causes severe diarrhea in piglets and results in serious economic losses. There are no effective vaccines and antiviral drugs to prevent and treat PDCoV infection currently. Griffithsin (GRFT) is a lectin with potent antiviral activity against enveloped viruses because of its ability to specifically bind N-linked high-mannose oligosaccharides. GRFT has been reported to possess antiviral activity against severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and porcine epidemic diarrhea virus (PEDV). Here, we first confirmed the antiviral activity of GRFT against PDCoV in vitro. The infected cells (%) and virus titers were significantly decreased at concentration 1 µg/mL or above of GRFT. Time-course experiments revealed that GRFT inhibits PDCoV infection at the adsorption and penetration step. GRFT binding to PDCoV spike (S) protein on the surface wraps the virus and blocks its entry. The outstanding antiviral potency indicates that GRFT has the potential value as a candidate drug for the prevention and treatment of PDCoV infection.


Subject(s)
Deltacoronavirus , Plant Lectins , Animals , Antiviral Agents/pharmacology , Cell Culture Techniques/veterinary , Coronavirus Infections/drug therapy , Coronavirus Infections/veterinary , Deltacoronavirus/drug effects , Plant Lectins/pharmacology , Swine , Swine Diseases/drug therapy
13.
Cell Prolif ; 54(9): e13091, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1320384

ABSTRACT

OBJECTIVES: Recent studies have shown the presence of SARS-CoV-2 in the tissues of clinically recovered patients and persistent immune symptoms in discharged patients for up to several months. Pregnant patients were shown to be a high-risk group for COVID-19. Based on these findings, we assessed SARS-CoV-2 nucleic acid and protein retention in the placentas of pregnant women who had fully recovered from COVID-19 and cytokine fluctuations in maternal and foetal tissues. MATERIALS AND METHODS: Remnant SARS-CoV-2 in the term placenta was detected using nucleic acid amplification and immunohistochemical staining of the SARS-CoV-2 protein. The infiltration of CD14+ macrophages into the placental villi was detected by immunostaining. The cytokines in the placenta, maternal plasma, neonatal umbilical cord, cord blood and amniotic fluid specimens at delivery were profiled using the Luminex assay. RESULTS: Residual SARS-CoV-2 nucleic acid and protein were detected in the term placentas of recovered pregnant women. The infiltration of CD14+ macrophages into the placental villi of the recovered pregnant women was higher than that in the controls. Furthermore, the cytokine levels in the placenta, maternal plasma, neonatal umbilical cord, cord blood and amniotic fluid specimens fluctuated significantly. CONCLUSIONS: Our study showed that SARS-CoV-2 nucleic acid (in one patient) and protein (in five patients) were present in the placentas of clinically recovered pregnant patients for more than 3 months after diagnosis. The immune responses induced by the virus may lead to prolonged and persistent symptoms in the maternal plasma, placenta, umbilical cord, cord blood and amniotic fluid.


Subject(s)
Cytokines/analysis , Placenta/virology , RNA, Viral/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Viral Proteins/isolation & purification , Adult , Amniotic Fluid/chemistry , COVID-19/pathology , Female , Fetal Blood/chemistry , Humans , Infant, Newborn , Macrophages/immunology , Nucleic Acid Amplification Techniques , Placenta/immunology , Pregnancy , RNA, Viral/blood , RNA, Viral/genetics , SARS-CoV-2/isolation & purification , Viral Proteins/blood
14.
Chaos ; 30(12): 123135, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-1003384

ABSTRACT

The rapid spread of COVID-19 worldwide presents a great challenge to epidemic modelers. Model outcomes vary widely depending on the characteristics of a pathogen and the models. Here, we present a logistic model for the epidemic spread and divide the spread of the novel coronavirus into two phases: the first phase is a natural exponential growth phase that occurs in the absence of intervention and the second phase is a regulated growth phase that is affected by enforcing social distancing and isolation. We apply the model to a number of pandemic centers. Our results are in good agreement with the data to date and show that social distancing significantly reduces the epidemic spread and flattens the curve. Predictions on the spreading trajectory including the total infections and peak time of new infections for a community of any size are made weeks ahead, providing the vital information and lead time needed to prepare for and mitigate the epidemic. The methodology presented here has immediate and far-reaching applications for ongoing outbreaks or similar future outbreaks of other emergent infectious diseases.


Subject(s)
COVID-19/epidemiology , COVID-19/transmission , Models, Biological , Pandemics , SARS-CoV-2 , Humans , Logistic Models
15.
Infect Drug Resist ; 13: 2637-2640, 2020.
Article in English | MEDLINE | ID: covidwho-703759

ABSTRACT

METHODS: Forty-four COVID-19 patients (severe/critical: N = 8, non-severe: N = 36) were examined by next generation sequencing (NGS) of nasopharyngeal test paper to observe the effect of novel coronavirus infection to the microbial composition in upper airway. RESULTS: In these nasopharyngeal test paper samples, 38 kinds of bacteria, 10 kinds of viruses except SARS-CoV-2, nine kinds of fungi and three kinds of atypical pathogens had been found. There was some difference in microbial composition in the upper airway between severe and non-severe cases. SUMMARY: These results are important for us to study the effect of SARS-CoV-2 on the local microbial composition of upper airway and prevent opportunistic infection in severe patients.

16.
J. Sch. Publ. ; 4(51):273-273–291, 2020.
Article in English | ELSEVIER | ID: covidwho-656461

ABSTRACT

This paper describes actions recently taken by the government, scholarly publishers, and researchers to face the COVID-19 challenge in China. By promulgating new policies and funding new programs, the Chinese government at all levels has provided huge support for research on COVID-19. Guided by the new policies, Chinese scholarly book publishers have published 124 new titles on the subject of the coronavirus. Journal publishers have put out numerous calls for papers and launched open access platforms for COVID-19 research. Chinese researchers have produced 2021 English-language papers and 2837 Chinese papers on COVID-19. These activities have the potential to affect scholarly publishing in China and around the world in multiple ways: 1) by establishing a more reasonable academic evaluation system in China;2) by bringing about a more balanced relationship between Chinese scholarly publishers' profit motive and their commitment to social welfare;and 3) by altering the communication channels that Chinese researchers use and the publishing choices they make.

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