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2.
Sci Rep ; 13(1): 19292, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37935815

RESUMEN

In this study, a deterministic model for the dynamics of Marburg virus transmission that incorporates the impact of public health education is being formulated and analyzed. The Caputo fractional-order derivative is used to extend the traditional integer model to a fractional-based model. The model's positivity and boundedness are also under investigation. We obtain the basic reproduction number [Formula: see text] and establish the conditions for the local and global asymptotic stability for the disease-free equilibrium of the model. Under the Caputo fractional-order derivative, we establish the existence-uniqueness theory using the Banach contraction mapping principle for the solution of the proposed model. We use functional techniques to demonstrate the proposed model's stability under the Ulam-Hyers condition. The numerical solutions are being determined through the Predictor-Corrector scheme. Awareness, as a form of education that lowers the risk of danger, is reducing susceptibility and the risk of infection. We employ numerical simulations to showcase the variety of realistic parameter values that support the argument that human awareness, as a form of education, considerably lowers susceptibility and the risk of infection.


Asunto(s)
Epidemias , Marburgvirus , Humanos , Educación en Salud , Número Básico de Reproducción , Escolaridad
3.
Math Biosci Eng ; 20(6): 10174-10199, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-37322928

RESUMEN

In this study, we examine the impact of vaccination and environmental transmission on the dynamics of the monkeypox. We formulate and analyze a mathematical model for the dynamics of monkeypox virus transmission under Caputo fractional order. We obtain the basic reproduction number, the conditions for the local and global asymptotic stability for the disease-free equilibrium of the model. Under the Caputo fractional order, existence and uniqueness solutions have been determined using fixed point theorem. Numerical trajectories are obtained. Furthermore, we explored some of the sensitive parameters impact. Based on the trajectories, we hypothesised that the memory index or fractional order could use to control the Monkeypox virus transmission dynamics. We observed that if the proper vaccination is administrated, public health education is given, and practice like personal hygiene and proper disinfection spray, the infected individuals decreases.


Asunto(s)
Desinfección , Monkeypox virus , Humanos , Número Básico de Reproducción , Educación en Salud , Vacunación
4.
Front Public Health ; 11: 1101436, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36875378

RESUMEN

In this study, a mathematical model for studying the dynamics of monkeypox virus transmission with non-pharmaceutical intervention is created, examined, and simulated using real-time data. Positiveness, invariance, and boundedness of the solutions are thus examined as fundamental features of mathematical models. The equilibrium points and the prerequisites for their stability are achieved. The basic reproduction number and thus the virus transmission coefficient ℜ0 were determined and quantitatively used to study the global stability of the model's steady state. Furthermore, this study considered the sensitivity analysis of the parameters according to ℜ0. The most sensitive variables that are important for infection control are determined using the normalized forward sensitivity index. Data from the United Kingdom collected between May and August 2022, which also aid in demonstrating the usefulness and practical application of the model to the spread of the disease in the United Kingdom, were used. In addition, using the Caputo-Fabrizio operator, Krasnoselskii's fixed point theorem has been used to analyze the existence and uniqueness of the solutions to the suggested model. The numerical simulations are presented to assess the system dynamic behavior. More vulnerability was observed when monkeypox virus cases first appeared recently as a result of numerical calculations. We advise the policymakers to consider these elements to control monkeypox transmission. Based on these findings, we hypothesized that another control parameter could be the memory index or fractional order.


Asunto(s)
Mpox , Humanos , Reino Unido , Número Básico de Reproducción , Control de Infecciones
5.
Partial Differ Equ Appl Math ; 6: 100455, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36277845

RESUMEN

This paper proposes a new fractal-fractional age-structure model for the omicron SARS-CoV-2 variant under the Caputo-Fabrizio fractional order derivative. Caputo-Fabrizio fractal-fractional order is particularly successful in modelling real-world phenomena due to its repeated memory effect and ability to capture the exponentially decreasing impact of disease transmission dynamics. We consider two age groups, the first of which has a population under 50 and the second of a population beyond 50. Our results show that at a population dynamics level, there is a high infection and recovery of omicron SARS-CoV-2 variant infection among the population under 50 (Group-1), while a high infection rate and low recovery of omicron SARS-CoV-2 variant infection among the population beyond 50 (Group-2) when the fractal-fractional order is varied.

6.
Comput Math Methods Med ; 2022: 6502598, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36158132

RESUMEN

Coinfection of Ebola virus and malaria is widespread, particularly in impoverished areas where malaria is already ubiquitous. Epidemics of Ebola virus disease arise on a sporadic basis in African nations with a high malaria burden. An observational study discovered that patients in Sierra Leone's Ebola treatment centers were routinely infected with malaria parasites, increasing the risk of death. In this paper, we study Ebola-malaria coinfections under the generalized Mittag-Leffler kernel fractional derivative. The Banach fixed point theorem and the Krasnoselskii type are used to analyse the model's existence and uniqueness. We discuss the model stability using the Hyers-Ulam functional analysis. The numerical scheme for the Ebola-malaria coinfections using Lagrange interpolation is presented. The numerical trajectories show that the prevalence of Ebola-malaria coinfections ranged from low to moderate depending on memory. This means that controlling the disease requires adequate knowledge of the past history of the dynamics of both malaria and Ebola. The graphical dynamics of the detection rate indicate that a variation in the detection rate only affects the following compartments: individuals that are latently infected with the Ebola, Ebola virus afflicted people who went unnoticed, individuals who have been infected with the Ebola virus and have been diagnosed with the disease, and persons undergoing Ebola virus therapy.


Asunto(s)
Coinfección , Ebolavirus , Epidemias , Fiebre Hemorrágica Ebola , Malaria , Coinfección/epidemiología , Fiebre Hemorrágica Ebola/complicaciones , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/terapia , Humanos , Malaria/complicaciones , Malaria/diagnóstico , Malaria/epidemiología
7.
Healthc Anal (N Y) ; 2: 100114, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37520617

RESUMEN

In this paper, we study a Caputo-Fabrizio fractional order epidemiological model for the transmission dynamism of the severe acute respiratory syndrome coronavirus 2 pandemic and its relationship with Alzheimer's disease. Alzheimer's disease is incorporated into the model by evaluating its relevance to the quarantine strategy. We use functional techniques to demonstrate the proposed model stability under the Ulam-Hyres condition. The Adams-Bashforth method is used to determine the numerical solution for our proposed model. According to our numerical results, we notice that an increase in the quarantine parameter has minimal effect on the Alzheimer's disease compartment.

8.
Saf Health Work ; 7(4): 284-292, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27924230

RESUMEN

BACKGROUND: In Ghana, fire incidents have become a regular occurrence, with thousands of lives and millions of dollars lost every year. Hardly a day passes without news of a fire outbreak in some part of Ghana, causing fear and panic among the people. This generates much discussion centering on rumors relating to politics, sabotage, misfortune, religious differences, etc. This article seeks to discuss the trend of fire incidents occurring in Ghana from 2000 to 2013 and the different ways to prevent these incidents. METHODS: The pattern of fire incidence in Ghana as a whole as well as in each region is discussed. The study took into consideration the causes, mechanisms, as well as preventive measures against the fire menace. Data were obtained from the head office of Ghana's national fire service. RESULTS: It was noticed that in general the rate of fire incidence increased each year. This increase was attributed to several factors: rate of population growth and industrialization, unstable electricity, urbanization, negligence, illegal electrical connection, etc. The cause of fire was categorized into domestic, industrial, vehicular, institutional, electrical, commercial, bush, and others. Among these causes, domestic fire accounted for 41% of the total number of fire incidents in the country. CONCLUSION: Finally, this study presents several recommendations to help prevent and mitigate fire incidents in Ghana.

9.
J Hazard Mater ; 307: 302-11, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26799221

RESUMEN

The risks associated with dust explosions still exist in industries that either process or handle combustible dust. This explosion risk could be prevented or mitigated by applying the principle of inherent safety (moderation). This is achieved by adding an inert material to a highly combustible material in order to decrease the ignition sensitivity of the combustible dust. The presented paper deals with the experimental investigation of the influence of adding an inert dust on the minimum ignition energy and the minimum ignition temperature of the combustible/inert dust mixtures. The experimental investigation was done in two laboratory scale equipment: the Hartmann apparatus and the Godbert-Greenwald furnace for the minimum ignition energy and the minimum ignition temperature test respectively. This was achieved by mixing various amounts of three inert materials (magnesium oxide, ammonium sulphate and sand) and six combustible dusts (brown coal, lycopodium, toner, niacin, corn starch and high density polyethylene). Generally, increasing the inert materials concentration increases the minimum ignition energy as well as the minimum ignition temperatures until a threshold is reached where no ignition was obtained. The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%.

10.
J Hazard Mater ; 304: 73-83, 2016 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-26546706

RESUMEN

The minimum ignition temperatures (MIT) of hybrid mixtures have been investigated by performing several series of tests in a modified Godbert-Greenwald furnace. Five dusts as well as three perfect gases and three real were used in different combinations as test samples. Further, seven mathematical models for prediction of the MIT of dust/air mixtures were presented of which three were chosen for deeper study and comparison with the experimental results based on the availability of the input quantities needed and their applicability. Additionally, two alternative models were proposed to calculate the MIT of hybrid mixtures and were validated against the experimental results. A significant decrease of the minimum ignition temperature of either the gas or the vapor as well as an increase in the explosion likelihood could be observed when a small amount of dust which was either below its minimum explosible concentration or not ignitable itself at that particular temperature was mixed with the gas. The various models developed by Cassel, Krishma and Mitsui to predict the MIT of dust were in good agreement with the experimental results as well as the two models proposed to predict the MIT of hybrid mixtures were also in agreement with the experimental value.

11.
J Hazard Mater ; 301: 314-26, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26378364

RESUMEN

Investigations on the minimum ignition temperatures (MIT) of hybrid mixtures of dusts with gases or solvents were performed in the modified Godbert-Greenwald (GG) furnace. Five combustible dusts and six flammable gases (three ideal and three real) were used. The test protocol was according to EN 50281-2-1 for dust-air mixtures whereas in the case of gases, solvents and hybrid mixtures this standard was used with slight modification. The experimental results demonstrated a significant decrease of the MIT of gas, solvent or dust and an increase in the likelihood of explosion when a small amount of dust, which was either below the minimum explosion concentration or not ignitable by itself, was mixed with gas and vice versa. For example, the MIT of toluene decreased from 540°C to 455°C when small amount of lycopodium was added. It was also confirmed that a hybrid mixture explosion is possible even when both dust and vapour or gas concentrations are respectively lower than their minimum explosion concentration (MEC) and lower explosion limit (LEL). Another example is CN4, the MEC of which of 304 g/m(3) decreased to 37 g/m(3) when propane was added, even though the concentrations of the gas was below its LEL.

12.
Saf Health Work ; 6(2): 146-50, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26106516

RESUMEN

Occupational health and safety (OHS) is a broad field of professional practice, which involves specialists from different disciplines including but not limited to engineers, occupational health physicians, physical and biological scientists, economists, and statisticians. The preventive systems required to ensure workers are protected from injuries and illnesses dwell heavily on engineers; however, the extent to which the engineer can go regarding planning and implementing preventive measures is dependent on specific legal requirements, leadership commitment from the company, organization, and nation. The objective of this paper is to identify the areas of opportunities for improvements in OHS management in Ghana with regard to the nation's legal requirements, commitment of the Ghana government, and Ghanaian leadership as well as appropriate structuring of Ghanaian institutions responsible for monitoring and managing OHS in Ghana. This paper identified Ghana's fragmented legal requirements concerning OHS, which are under different jurisdictions with unclear responsibilities and accountabilities. The paper also highlights the training needs of Ghanaian academic institutions regarding OHS. Among other recommendations made including structuring of Ghanaian institutions to manage OHS in line with the ILO-OSH 2001, this paper aligns the recommendations with the articles and elements of International Labour Organization convention number 155 and OHSAS 18001 elements.

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