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1.
National Center for Education Statistics ; 2023.
Article in English | ProQuest Central | ID: covidwho-20237184

ABSTRACT

The "Report on the Condition of Education" is a congressionally mandated annual report from the National Center for Education Statistics (NCES). Using the most recent data available (at the time this report was written) from NCES and other sources, the report contains key indicators on the condition of education in the United States at all levels, from prekindergarten through postsecondary, as well as labor force outcomes and international comparisons. There are core indicators that are updated every year and spotlight indicators that provide in-depth analyses on topics of interest to education agencies, policymakers, researchers, and the public. At the broadest level, the Condition of Education Indicator System is organized into five sections: family characteristics;preprimary, elementary, and secondary education;postsecondary education;population characteristics and economic outcomes;and international comparisons. The Report on the "Condition of Education 2023" encompasses key findings from the Condition of Education Indicator System. The full contents of the Indicator System can be accessed online through the website or by downloading PDFs for the individual indicators. [For "The Condition of Education 2023": At a Glance, see ED628291. For the "Report on the Condition of Education 2022. NCES 2022-144," see ED619870.]

2.
Discontinuity, Nonlinearity, and Complexity ; 12(3):511-537, 2023.
Article in English | Scopus | ID: covidwho-20235204

ABSTRACT

This work considers a new stochastic mathematical model for the transmission dynamics of the coronavirusCOVID-19 by providing the healthy compartment together with the quarantine/isolation compartment. In the deterministic model, global stability conditions of the disease-free equilibrium E0 and the endemic equilibrium E*are derived in terms of the threshold quantity Rd0. Based on the chaotic behavior, we develop and analyze a fourdimensional stochastic COVID-19 epidemic model. Uniqueness, boundedness, and positiveness of the proposed stochastic model are investigated in a biologically feasible region. In terms of the stochastic basic reproduction number Rs0 of the stochastic model, extinction and persistence of the COVID-19 disease are derived. Our theoretical findings are supported by some numerical simulations. The sensitivity of the model with respect to the parameters involved in the system is studied to investigate the most sensitive parameter towards the highest number of infected individuals. We confirm the stability analysis by showing the elasticity of Rs 0 with respect to the variation of each parameter. We present real data of a case study with the first wave of the COVID-19 epidemic in the United Kingdom. We compare our numerical results with the real data. © 2023 L&H Scientific Publishing, LLC. All rights reserved.

3.
Journal of Cases in Educational Leadership ; 26(1):71-81, 2023.
Article in English | ProQuest Central | ID: covidwho-20233809

ABSTRACT

Predominantly white institutions (PWIs) struggle to attract and retain underrepresented faculty. Despite aspirations for diversity, the reality remains that underrepresented faculty are not hired and retained in numbers sufficient to change the institution's demographics. The leadership of PWIs strives for solutions to ameliorate the trend in recruitment, retention, and climate. The issue has gained even more significance recently due to the global coronavirus pandemic when layoffs, non-renewals, and hiring freezes have been widely imposed. This case examines how systemic leadership problems, mindsets, and climates keep PWIs at the status quo, and invites application of leadership and adult learning theories to develop a strategy for improving faculty diversity at PWIs.

4.
Syst Rev ; 12(1): 92, 2023 06 02.
Article in English | MEDLINE | ID: covidwho-20242730

ABSTRACT

BACKGROUND: Intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections play a key role in treating a range of macular diseases. The effectiveness of these therapies is dependent on patients' adherence (the extent to which a patient takes their medicines as per agreed recommendations from the healthcare provider) and persistence (continuation of the treatment for the prescribed duration) to their prescribed treatment regimens. The aim of this systematic review was to demonstrate the need for further investigation into the prevalence of, and factors contributing to, patient-led non-adherence and non-persistence, thus facilitating improved clinical outcomes. METHODS: Systematic searches were conducted in Google Scholar, Web of Science, PubMed, MEDLINE, and the Cochrane Library. Studies in English conducted before February 2023 that reported the level of, and/or barriers to, non-adherence or non-persistence to intravitreal anti-VEGF ocular disease therapy were included. Duplicate papers, literature reviews, expert opinion articles, case studies, and case series were excluded following screening by two independent authors. RESULTS: Data from a total of 409,215 patients across 52 studies were analysed. Treatment regimens included pro re nata, monthly and treat-and-extend protocols; study durations ranged from 4 months to 8 years. Of the 52 studies, 22 included a breakdown of reasons for patient non-adherence/non-persistence. Patient-led non-adherence varied between 17.5 and 35.0% depending on the definition used. Overall pooled prevalence of patient-led treatment non-persistence was 30.0% (P = 0.000). Reasons for non-adherence/non-persistence included dissatisfaction with treatment results (29.9%), financial burden (19%), older age/comorbidities (15.5%), difficulty booking appointments (8.5%), travel distance/social isolation (7.9%), lack of time (5.8%), satisfaction with the perceived improvement in their condition (4.4%), fear of injection (4.0%), loss of motivation (4.0%), apathy towards eyesight (2.5%), dissatisfaction with facilities 2.3%, and discomfort/pain (0.3%). Three studies found non-adherence rates between 51.6 and 68.8% during the COVID-19 pandemic, in part due to fear of exposure to COVID-19 and difficulties travelling during lockdown. DISCUSSION: Results suggest high levels of patient-led non-adherence/non-persistence to anti-VEGF therapy, mostly due to dissatisfaction with treatment results, a combination of comorbidities, loss of motivation and the burden of travel. This study provides key information on prevalence and factors contributing to non-adherence/non-persistence in anti-VEGF treatment for macular diseases, aiding identification of at-risk individuals to improve real-world visual outcomes. Improvements in the literature can be achieved by establishing uniform definitions and standard timescales for what constitutes non-adherence/non-persistence. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42020216205.


Subject(s)
Angiogenesis Inhibitors , Eye Diseases , Ranibizumab , Humans , Angiogenesis Inhibitors/therapeutic use , Ranibizumab/therapeutic use , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Medication Adherence , Eye Diseases/drug therapy
5.
Aims Microbiology ; 9(3):431-443, 2023.
Article in English | Web of Science | ID: covidwho-20231397

ABSTRACT

To minimize health risks, surrogates are often employed to reduce experiments with pathogenic microorganisms and the associated health risk. Due to structural similarities between the enveloped RNA -viruses SARS-CoV-2 and Phi6, the latter has been established as a nonpathogenic coronavirus surrogate for many applications. However, large discrepancies in the UV log-reduction doses between SARS-CoV-2 and Phi6 necessitate the search for a better surrogate for UV inactivation applications. A literature study provided the bacteriophage PhiX174 as a potentially more suitable nonpathogenic coronavirus surrogate candidate. In irradiation experiments, the sensitivity of PhiX174 was investigated upon exposure to UV radiation of wavelengths 222 nm (Far-UVC), 254 nm (UVC), 302 nm (broad-band UVB), 311 nm (narrow-band UVB) and 366 nm (UVA) using a plaque assay. The determined log-reduction doses for PhiX174 were 1.3 mJ/cm2 @ 222 nm, 5 mJ/cm2 @ 254 nm, 17.9 mJ/cm2 @ 302 nm, 625 mJ/cm2 @ 311 nm and 42.5 J/cm2 @ 366 nm. The comparison of these results with published log-reduction doses of SARS-CoV-2 in the same spectral region, led to the conclusion that the bacteriophage PhiX174 exhibits larger log-reduction doses than SARS-CoV-2, nevertheless, it is a better UV-surrogate at 222 nm (Far-UVC), 254 nm (UVC) and 302 nm (UVB) than the often applied Phi6.

6.
Corporate Social Responsibility and Environmental Management ; 2023.
Article in English | Web of Science | ID: covidwho-20231183

ABSTRACT

The Sustainable Development Goals of the United Nation and interest by investors in Environmental, Social and Governance (ESG) investment strategies have caused a rapid shift to the green or renewable energy sector, from traditional or gray (oil, gas, and coal) energy companies. In this study, we examine whether and to what extent, financially speaking, there is a price to pay for investing in renewable energy sector equity. Moreover, we seek to determine whether green investments can be considered a hedge during times of financial stress. We find that alphas from investments in a portfolio of gray (overall energy sector) stocks and versus a portfolio of renewable energy equities during an exogenous, non-financial shock-the COVID-19 pandemic-and during non-crisis periods did not differ statistically. However, the renewable energy index showed higher idiosyncratic volatility than the energy index, as expected. The results are robust to alternative model specifications. From a practical perspective, our results are informative in that they provide insights into the tradeoffs associated with renewable energy investments. In particular, risk-adjusted returns to a renewable energy portfolio may be affected by greater idiosyncratic risk.

7.
BMC Urol ; 23(1): 64, 2023 Apr 24.
Article in English | MEDLINE | ID: covidwho-2322806

ABSTRACT

BACKGROUND: Overactive bladder (OAB) is defined as urinary urgency accompanied by frequency and nocturia, with or without urge urinary incontinence (UUI). Vibegron, a selective ß3-adrenergic receptor agonist approved in the US in December 2020, demonstrated efficacy in reducing symptoms of OAB and was safe and well tolerated in the 12-week EMPOWUR trial and its 40-week, double-blind extension trial. The goal of the COMPOSUR study is to evaluate vibegron in a real-world setting to assess patient treatment satisfaction, tolerability, safety, duration of treatment, and persistence. METHODS: This is a 12-month, prospective, observational, real-world study, with an optional 12-month extension to 24 months, in the US assessing adults ≥ 18 years old starting a new course of vibegron. Patients must be previously diagnosed with OAB with or without UUI, symptomatic for ≥ 3 months before enrollment, and receive prior treatment with an anticholinergic, with mirabegron, or with a combination of an anticholinergic and mirabegron. Enrollment is performed by the investigator following exclusion and inclusion criteria guided by US product labeling, reinforcing a real-world approach. Patients complete the OAB Satisfaction with Treatment Questionnaire (OAB-SAT-q) monthly and the OAB Questionnaire short form (OAB-q-SF) and Work Productivity and Activity Impairment Questionnaire (WPAI:US) at baseline and monthly for 12 months. Patients are followed up via phone call, in-person visits, or telehealth (ie, virtual) visits. The primary endpoint is patient treatment satisfaction as determined by the OAB-SAT-q satisfaction domain score. Secondary endpoints include percent positive responses to individual OAB-SAT-q questions, additional OAB-SAT-q domain scores, and safety. Exploratory endpoints include adherence and persistence. DISCUSSION: OAB leads to a significant decrease in quality of life, as well as impairment of work activities and productivity. Persistence with OAB treatments can be challenging, often due to lack of efficacy and adverse effects. COMPOSUR is the first study to provide long-term, prospective, pragmatic treatment data for vibegron in the US and the resultant effect on quality of life among patients with OAB in a real-world clinical setting. Trial registration ClinicalTrials.gov identifier: NCT05067478; registered: October 5, 2021.


Subject(s)
Urinary Bladder, Overactive , Adult , Humans , Adolescent , Urinary Bladder, Overactive/drug therapy , Quality of Life , Prospective Studies , Treatment Outcome , Acetanilides/therapeutic use , Double-Blind Method , Cholinergic Antagonists/therapeutic use , Adrenergic beta-3 Receptor Agonists/therapeutic use , Muscarinic Antagonists/therapeutic use
8.
Dissertation Abstracts International Section A: Humanities and Social Sciences ; 84(8-A):No Pagination Specified, 2023.
Article in English | APA PsycInfo | ID: covidwho-2319073

ABSTRACT

The unprecedented shift to online learning during the COVID-19 pandemic presented a unique opportunity to research adult English language learners' lived experiences of online learning and motivations for persistence. With the growing trend of offering online learning to adult learners and concerns over the high attrition rates associated with this method (Nagel, 2009), it is critical to analyze adult English language learners' lived experiences of online learning and motivations for persistence to inform pedagogical practices that will promote learner retention in online formats. The purpose of this study was to extend the current research through the lens of self-determination theory and the idea that when individuals' basic psychological needs of autonomy, competence, and relatedness are satisfied, intrinsic motivation is promoted (Deci & Ryan, 1985). Research shows learners who are intrinsically motivated undertake learning for inherent satisfaction, become actively engaged, and persist when faced with challenges (Ryan & Deci, 2000b). Using a phenomenological approach, this study was designed to examine the lived experiences of six participants from one adult literacy center located in the Northeastern United States who had participated in online learning for at least 6 months during the COVID-19 pandemic. Findings from a series of semi-structured interviews indicated four major themes: challenges of online learning for adult English language learners, needs of adult English language learners in online learning, benefits of online learning for adult English language learners, and adult English language learners' motivations for persistence. Results show that when considering adult English language learners' basic psychological needs for autonomy, competence, and relatedness as a way to promote motivation, educators should account for learners' unique cultural differences, including backgrounds, attitudes, and goals. (PsycInfo Database Record (c) 2023 APA, all rights reserved)

9.
Elife ; 122023 05 04.
Article in English | MEDLINE | ID: covidwho-2313571

ABSTRACT

The COVID-19 global pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has infected hundreds of millions of individuals. Following COVID-19 infection, a subset can develop a wide range of chronic symptoms affecting diverse organ systems referred to as post-acute sequelae of SARS-CoV-2 infection (PASC), also known as long COVID. A National Institutes of Health-sponsored initiative, RECOVER: Researching COVID to Enhance Recovery, has sought to understand the basis of long COVID in a large cohort. Given the range of symptoms that occur in long COVID, the mechanisms that may underlie these diverse symptoms may also be diverse. In this review, we focus on the emerging literature supporting the role(s) that viral persistence or reactivation of viruses may play in PASC. Persistence of SARS-CoV-2 RNA or antigens is reported in some organs, yet the mechanism by which they do so and how they may be associated with pathogenic immune responses is unclear. Understanding the mechanisms of persistence of RNA, antigen or other reactivated viruses and how they may relate to specific inflammatory responses that drive symptoms of PASC may provide a rationale for treatment.


Subject(s)
COVID-19 , Post-Acute COVID-19 Syndrome , United States , Humans , RNA, Viral , SARS-CoV-2 , Disease Progression
10.
J Clin Immunol ; 2023 May 06.
Article in English | MEDLINE | ID: covidwho-2313515

ABSTRACT

PURPOSE: COVID-19 infection in immunodeficient individuals can result in chronically poor health, persistent or relapsing SARS-CoV-2 PCR positivity, and long-term infectious potential. While clinical trials have demonstrated promising outcomes using anti-SARS-CoV-2 medicines in immunocompetent hosts, their ability to achieve sustained viral clearance in immunodeficient patients remains unknown. We therefore aimed to study long-term virological outcomes in patients treated at our centre. METHODS: We followed up immunocompromised inpatients treated with casirivimab-imdevimab (Ronapreve) between September and December 2021, and immunocompromised patients who received sotrovimab, molnupiravir, nirmatrelvir/ritonavir (Paxlovid), or no treatment from December 2021 to March 2022. Nasopharyngeal swab and sputum samples were obtained either in hospital or in the community until sustained viral clearance, defined as 3 consecutive negative PCR samples, was achieved. Positive samples were sequenced and analysed for mutations of interest. RESULTS: We observed sustained viral clearance in 71 of 103 patients, none of whom died. Of the 32/103 patients where sustained clearance was not confirmed, 6 died (between 2 and 34 days from treatment). Notably, we observed 25 cases of sputum positivity despite negative nasopharyngeal swab samples, as well as recurrence of SARS-CoV-2 positivity following a negative sample in 12 cases. Patients were then divided into those who cleared within 28 days and those with PCR positivity beyond 28 days. We noted lower B cell counts in the group with persistent PCR positivity (mean (SD) 0.06 (0.10) ×109/L vs 0.22 (0.28) ×109/L, p = 0.015) as well as lower IgA (median (IQR) 0.00 (0.00-0.15) g/L vs 0.40 (0.00-0.95) g/L, p = 0.001) and IgM (median (IQR) 0.05 (0.00-0.28) g/L vs 0.35 (0.10-1.10) g/L, p = 0.005). No differences were seen in CD4+ or CD8+ T cell counts. Antiviral treatment did not impact risk of persistent PCR positivity. CONCLUSION: Persistent SARS-CoV-2 PCR positivity is common among immunodeficient individuals, especially those with antibody deficiencies, regardless of anti-viral treatment. Peripheral B cell count and serum IgA and IgM levels are predictors of viral persistence.

11.
Frontiers in Built Environment ; 9, 2023.
Article in English | Web of Science | ID: covidwho-2309730

ABSTRACT

Indoor residents are constantly exposed to dynamic microbiota that have significant health effects. In addition to hand hygiene, cleaning, and disinfection, antimicrobial coatings (AMCs) can prevent the spread of infectious diseases in public areas. The sustainable use of antimicrobial-coated products requires an assessment of their pros and cons for human health and the environment. The toxicity and resistance risks of AMCs have been considered, but large-scale genetic studies on the microbial community compositions and resistomes of AMCs are scarce. The use of an AMC can reduce the total number of microbes on a surface but poses the risk of dysbiosis, microbial imbalance, such as the polarized growth of metallophilic, metal- and antimicrobial-resistant, and other survivor bacteria, and the overall reduction of microbial diversity. Loss of diversity may lead to the enrichment of harmful bacteria and an increased risk of communicable or immunological non-communicable inflammatory diseases (NCDs). In public buildings, such as kindergartens and nursing homes for the elderly, the use of AMCs is likely to increase due to epidemics and pandemics in recent years. Therefore, comprehensive metagenomic research is needed to monitor the effects of AMCs on indoor microbial community compositions and functions. Although the determination of good indoor microbiota and homeostasis is difficult, microbial communities that have health-protective or harmful effects can and should be identified using a metagenomic sequencing approach before the large-scale implementation of AMCs.

12.
Journal of the European Economic Association ; 2023.
Article in English | Web of Science | ID: covidwho-2308664

ABSTRACT

This study proposes a real-time estimate of inattention, based on micro-level data. I show that a simple specification that estimates the persistence of a forecaster's deviation from the mean provides a direct estimate of parameters of information frictions according to prominent models of expectations. The new estimate can also be interpreted as a hybrid measure of both information frictions and behavioral frictions. Using the new specification, I revise several key findings documented in the previous literature. I find higher levels of inattention and document new forms of variations over time and across variables, horizons, individuals, and types of agents. I also report new results from long-run forecasts and document an unprecedented response to COVID-19.

13.
Computation ; 11(3), 2023.
Article in English | Web of Science | ID: covidwho-2308322

ABSTRACT

This article formulates and analyzes a discrete-time Human immunodeficiency virus type 1 (HIV-1) and human T-lymphotropic virus type I (HTLV-I) coinfection model with latent reservoirs. We consider that the HTLV-I infect the CD4(+)T cells, while HIV-1 has two classes of target cells-CD4(+)T cells and macrophages. The discrete-time model is obtained by discretizing the original continuous-time by the non-standard finite difference (NSFD) approach. We establish that NSFD maintains the positivity and boundedness of the model's solutions. We derived four threshold parameters that determine the existence and stability of the four equilibria of the model. The Lyapunov method is used to examine the global stability of all equilibria. The analytical findings are supported via numerical simulation. The impact of latent reservoirs on the HIV-1 and HTLV-I co-dynamics is discussed. We show that incorporating the latent reservoirs into the HIV-1 and HTLV-I coinfection model will reduce the basic HIV-1 single-infection and HTLV-I single-infection reproductive numbers. We establish that neglecting the latent reservoirs will lead to overestimation of the required HIV-1 antiviral drugs. Moreover, we show that lengthening of the latent phase can suppress the progression of viral coinfection. This may draw the attention of scientists and pharmaceutical companies to create new treatments that prolong the latency period.

14.
J Math Biol ; 86(5): 65, 2023 03 30.
Article in English | MEDLINE | ID: covidwho-2311810

ABSTRACT

The perception of susceptible individuals naturally lowers the transmission probability of an infectious disease but has been often ignored. In this paper, we formulate and analyze a diffusive SIS epidemic model with memory-based perceptive movement, where the perceptive movement describes a strategy for susceptible individuals to escape from infections. We prove the global existence and boundedness of a classical solution in an n-dimensional bounded smooth domain. We show the threshold-type dynamics in terms of the basic reproduction number [Formula: see text]: when [Formula: see text], the unique disease-free equilibrium is globally asymptotically stable; when [Formula: see text], there is a unique constant endemic equilibrium, and the model is uniformly persistent. Numerical analysis exhibits that when [Formula: see text], solutions converge to the endemic equilibrium for slow memory-based movement and they converge to a stable periodic solution when memory-based movement is fast. Our results imply that the memory-based movement cannot determine the extinction or persistence of infectious disease, but it can change the persistence manner.


Subject(s)
Communicable Diseases , Epidemics , Humans , Computer Simulation , Models, Biological , Communicable Diseases/epidemiology , Basic Reproduction Number , Disease Susceptibility/epidemiology
15.
Resources Policy ; 82, 2023.
Article in English | Scopus | ID: covidwho-2292259

ABSTRACT

As a precious metal and investment commodity, gold has been signified to be important for risk management, diversification, and hedging. The gold market has undergone considerable structural changes in the facet of the pandemic and other geopolitical developments, attracting the interest of investors. Thus, it is crucial to look into how these structural changes affect the efficiency of the market. Accordingly, the study examines and compares the evolution of the gold market efficiency in three major economies from January 1, 2018, to August 31, 2022: India, USA, and Brazil. For this, we first decompose the time series using Loess Smoother's Seasonal and Trend Decomposition and then employ a multifractal detrended fluctuation analysis approach. The estimates are strengthened by the alternative approach of the rolling window method of wild bootstrap automatic variance ratio. The findings indicate a considerable decline in the efficiency of the gold returns across three economies, with the highest decline in India, followed by USA and Brazil. Notably, during covid and post covid periods, India and USA show persistence in small fluctuations, while Brazil displays persistent behavior in large fluctuations. Thereby, the market panic makes the gold market unstable, and its use as a safe haven is "erratic”. © 2023 Elsevier Ltd

16.
Oriental Journal of Chemistry ; 37(2):285-294, 2021.
Article in English | ProQuest Central | ID: covidwho-2299927

ABSTRACT

This review highlights origin, symptoms, diagnosis, causative agents, mode of transmission and persistence of coronavirus disease (COVID-19) through human activities. In the current scenario researchers, doctors and scientists are striving to combat the transmission of COVID-19 among society. Origin and growth of pandemic has raised the serious concern to address the causative agents, mode of transmission, persistence, preventive measures, diagnosis and possibilities of treatment. The broad-spectrum antiviral antiphrastic, complementary and alternative medicines are currently proposed for possible eradication of the pandemic. The current world is relying on, prevention and control of infection through sanitization and quarantine and onwards waiting for appropriate virucidal agents, sanitizers and strategic vaccination and immunization to combat the pandemic of SARS-CoV-2. Eradication of COVID-19 under stringent guidelines of WHO regarding social practices, intensive care, administration of complementary medicines and innovation of vaccines are under active considerations across the world to combat the pandemic.

17.
Social and Personality Psychology Compass ; 2023.
Article in English | Scopus | ID: covidwho-2299881

ABSTRACT

Graduating during COVID-19, the Class of 2020 had difficulty pursuing their future goals. This research examined the likelihood of academic and career goal change early in the pandemic, disparities in persistence by socioeconomic status (SES), and how psychological resources mitigated goal change during the early stages of the pandemic. This 4-year study surveyed students in the Class of 2020 eight times from their first week in college (Fall 2016) to their last semester before graduation (Spring 2020;N = 115;20% below middle SES, 80% middle SES or above). Even in the first weeks of COVID-19, a quarter of students changed goals. Lower SES students were less likely to persist in their post-graduation plans. Nevertheless, students who entered college with a vivid image of their future were more likely to have secured a graduate school or job prospect prior to COVID-19, and, in turn, were less likely to change goals. © 2023 John Wiley & Sons Ltd.

18.
Mathematics ; 11(8):1806, 2023.
Article in English | ProQuest Central | ID: covidwho-2298655

ABSTRACT

When an individual with confirmed or suspected COVID-19 is quarantined or isolated, the virus can linger for up to an hour in the air. We developed a mathematical model for COVID-19 by adding the point where a person becomes infectious and begins to show symptoms of COVID-19 after being exposed to an infected environment or the surrounding air. It was proven that the proposed stochastic COVID-19 model is biologically well-justifiable by showing the existence, uniqueness, and positivity of the solution. We also explored the model for a unique global solution and derived the necessary conditions for the persistence and extinction of the COVID-19 epidemic. For the persistence of the disease, we observed that Rs0>1, and it was noticed that, for Rs<1, the COVID-19 infection will tend to eliminate itself from the population. Supplementary graphs representing the solutions of the model were produced to justify the obtained results based on the analysis. This study has the potential to establish a strong theoretical basis for the understanding of infectious diseases that re-emerge frequently. Our work was also intended to provide general techniques for developing the Lyapunov functions that will help the readers explore the stationary distribution of stochastic models having perturbations of the nonlinear type in particular.

19.
Mathematics ; 11(8):1851, 2023.
Article in English | ProQuest Central | ID: covidwho-2297164

ABSTRACT

At the beginning of the COVID-19 pandemic, the entire world was waiting for a medical solution (for example, vaccines) in order to return to normality. Sanitary restrictions changed our consumption behaviors and feelings. Therefore, this paper analyzes the stochastic properties of consumer sentiment during the COVID-19 episode and the appearance of vaccines against the virus in December 2020 in the United States of America. This study adds a new dimension to the literature because it is the first research paper that uses advanced methodologies based on fractional integration and fractional cointegration analysis to understand the statistical properties of these time series and their behavior in the long term. The results using fractional integration methodologies exhibit a high degree of persistence, finding behavior of mean reversion during the pandemic episode. Therefore, the shock duration in consumer sentiment will be transitory, recovering to its previous trend in the short run. Focusing on the cointegrating part, we arrive at two main conclusions. First, an increase in total vaccination produces a positive reaction or impact on the behavior of consumers. On the other hand, an increase in new COVID-19 cases negatively affects the behavior of the consumer.

20.
J Infect ; 86(6): 574-583, 2023 06.
Article in English | MEDLINE | ID: covidwho-2303587

ABSTRACT

BACKGROUND: Heterologous COVID vaccine priming schedules are immunogenic and effective. This report aims to understand the persistence of immune response to the viral vectored, mRNA and protein-based COVID-19 vaccine platforms used in homologous and heterologous priming combinations, which will inform the choice of vaccine platform in future vaccine development. METHODS: Com-COV2 was a single-blinded trial in which adults ≥ 50 years, previously immunised with single dose 'ChAd' (ChAdOx1 nCoV-19, AZD1222, Vaxzevria, Astrazeneca) or 'BNT' (BNT162b2, tozinameran, Comirnaty, Pfizer/BioNTech), were randomised 1:1:1 to receive a second dose 8-12 weeks later with either the homologous vaccine, or 'Mod' (mRNA-1273, Spikevax, Moderna) or 'NVX' (NVX-CoV2373, Nuvaxovid, Novavax). Immunological follow-up and the secondary objective of safety monitoring were performed over nine months. Analyses of antibody and cellular assays were performed on an intention-to-treat population without evidence of COVID-19 infection at baseline or for the trial duration. FINDINGS: In April/May 2021, 1072 participants were enrolled at a median of 9.4 weeks after receipt of a single dose of ChAd (N = 540, 45% female) or BNT (N = 532, 39% female) as part of the national vaccination programme. In ChAd-primed participants, ChAd/Mod had the highest anti-spike IgG from day 28 through to 6 months, although the heterologous vs homologous geometric mean ratio (GMR) dropped from 9.7 (95% CI (confidence interval): 8.2, 11.5) at D28 to 6.2 (95% CI: 5.0, 7.7) at D196. The heterologous/homologous GMR for ChAd/NVX similarly dropped from 3.0 (95% CI:2.5,3.5) to 2.4 (95% CI:1.9, 3.0). In BNT-primed participants, decay was similar between heterologous and homologous schedules with BNT/Mod inducing the highest anti-spike IgG for the duration of follow-up. The adjusted GMR (aGMR) for BNT/Mod compared with BNT/BNT increased from 1.36 (95% CI: 1.17, 1.58) at D28 to 1.52 (95% CI: 1.21, 1.90) at D196, whilst for BNT/NVX this aGMR was 0.55 (95% CI: 0.47, 0.64) at day 28 and 0.62 (95% CI: 0.49, 0.78) at day 196. Heterologous ChAd-primed schedules produced and maintained the largest T-cell responses until D196. Immunisation with BNT/NVX generated a qualitatively different antibody response to BNT/BNT, with the total IgG significantly lower than BNT/BNT during all follow-up time points, but similar levels of neutralising antibodies. INTERPRETATION: Heterologous ChAd-primed schedules remain more immunogenic over time in comparison to ChAd/ChAd. BNT-primed schedules with a second dose of either mRNA vaccine also remain more immunogenic over time in comparison to BNT/NVX. The emerging data on mixed schedules using the novel vaccine platforms deployed in the COVID-19 pandemic, suggest that heterologous priming schedules might be considered as a viable option sooner in future pandemics. ISRCTN: 27841311 EudraCT:2021-001275-16.


Subject(s)
COVID-19 , Vaccines , Adult , Female , Humans , Male , COVID-19 Vaccines , ChAdOx1 nCoV-19 , BNT162 Vaccine , Pandemics , Single-Blind Method , COVID-19/prevention & control , Vaccination , Immunity , Immunoglobulin G , Antibodies, Viral
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