In this paper, a modified SEIR epidemic model incorporating shedding effect is proposed to analyze transmission dynamics of the COVID-19 virus among different individuals' classes. The direct impact of pathogen concentration over susceptible populations through the shedding of COVID-19 virus into the environment is investigated. Moreover, the threshold value of shedding parameters is computed which gives information about their significance in decreasing the impact of the disease. The basic reproduction number ( ) is calculated using the next-generation matrix method, taking shedding as a new infection. In the absence of disease, the condition for the equilibrium point to be locally and globally asymptotically stable with are established. It has been shown that the unique endemic equilibrium point is globally asymptotically stable under the condition . Bifurcation theory and center manifold theorem imply that the system exhibit backward bifurcation at . The sensitivity indices of are computed to investigate the robustness of model parameters. The numerical simulation is demonstrated to illustrate the results.
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http://dx.doi.org/10.1007/s12190-022-01792-1 | DOI Listing |
Sensors (Basel)
January 2025
Laboratory Engineering System, Hassania School of Public Works, Casablanca BP 8108, Morocco.
This paper presents a systematic review that explores the latest advancements in predictive maintenance methods and cybersecurity for solar panel systems, shedding light on the advantages and challenges of the most recent developments in predictive maintenance techniques for solar plants. Numerous important research studies, reviews, and empirical studies published between 2018 and 2023 are examined. These technologies help in detecting defects, degradation, and anomalies in solar panels by facilitating early intervention and reducing the probability of inverter failures.
View Article and Find Full Text PDFSci Rep
January 2025
College of Engineering, Arab Academy for Science, Technology and Maritime Transport, Alexandria, Egypt.
Bladeless wind turbines face operational limitations due to the lock-in phenomenon. This study introduces two novel mechanisms for designing bladeless wind turbines to address this issue, enabling operation across a broad wind speed range from 2 to 10 m/s while ensuring that lock-in conditions are satisfied at any wind speed within this range. The study aims to maintain optimal performance without any decline that is observed in conventional bladeless wind turbines by controlling the turbine's natural frequency through implementing these mechanisms, either by adjusting the effective length of the stand or by incorporating an additional mass in the hollow mast, or both.
View Article and Find Full Text PDFMicroorganisms
December 2024
State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bio-Resources, College of Life Science and Technology, Guangxi University, 100 Daxue Road, Nanning 530004, China.
Integrons, which are genetic components commonly found in bacteria, possess the remarkable capacity to capture gene cassettes, incorporate them into their structure, and thereby contribute to an increase in genomic complexity and phenotypic diversity. This adaptive mechanism allows integrons to play a significant role in acquiring, expressing, and spreading antibiotic resistance genes in the modern age. To assess the current challenges posed by integrons, it is necessary to have a thorough understanding of their characteristics.
View Article and Find Full Text PDFBiomolecules
December 2024
Department of Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, 25123 Brescia, Italy.
Background: Brain calcifications, found in various conditions, may be incidental or crucial for diagnosis. They occur in physiological changes, infections, genetic diseases, neurodegenerative conditions, vascular syndromes, metabolic disorders, endocrine disorders, and primary tumors like oligodendroglioma. While often incidental, their presence can be vital for accurate diagnosis.
View Article and Find Full Text PDFAnalyst
January 2025
Physics and Astronomy, University of Exeter, Exeter, EX4 4QL, UK.
The seed coat plays a pivotal role in seed development and germination, acting as a protective barrier and mediating interac-tions with the external environment. Traditional histochemical techniques and analytical methods have provided valuable insights into seed coat composition and function. However, these methods often suffer from limitations such as indirect chemical signatures and lack of spatial resolution.
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