EXPLORING THE EFFECTS OF PARAMETER HETEROGENEITY ON THE INTRINSIC DYNAMICS OF HIV/AIDS IN HETEROSEXUAL SETTINGS

2011 ◽  
Vol 04 (01) ◽  
pp. 75-92
Author(s):  
E. T. NGARAKANA-GWASIRA ◽  
C. P. BHUNU ◽  
S. MUSHAYABASA ◽  
S. D. HOVE-MUSEKWA ◽  
W. GARIRA ◽  
...  
Keyword(s):  
Population Heterogeneity ◽  
Transmission Dynamics ◽  
Heterosexual Transmission ◽  
Related Parameter ◽  
Basic Model ◽  
Progression Model ◽  
Mathematical Properties ◽  
Parameter Heterogeneity ◽  
Epidemiological Parameters ◽  
Hiv Aids

A sex-structured staged progression model for heterosexual transmission dynamics of HIV/AIDS in a community to theoretically assess the effects of gender parameter accounting for population heterogeneity is formulated and analyzed. The basic model without this parameter is analyzed, and then extended to include gender heterogeneity in order to explore its role on the transmission dynamics of the disease. Mathematical properties including epidemic thresholds known as reproductive numbers are derived. The models are numerically analysed using some demographic and epidemiological parameters for Zimbabwe. These simulations suggest that the use of identical gender attributes simplifies computation at the expense of reality as it underestimates the size of the epidemic by 5%. This study demonstrates that the use of gender related parameter in the transmission dynamics of HIV gives a better estimate of the prevalence of the epidemic and should be given prominence.

scholarly journals The Dynamic of Heterosexual Transmission of HIV-AIDS Model with Treatment

2017 ◽  
Vol 6 (2) ◽  
Author(s):  
Kehinde Adekunle Bashiru
Keyword(s):  
Mathematical Model ◽  
Equilibrium Points ◽  
Model System ◽  
Transmission Dynamics ◽  
Heterosexual Transmission ◽  
Asymptotically Stable ◽  
Effect Of Treatment ◽  
The Impact ◽  
Disease Free ◽  
Hiv Aids

A Mathematical Model of HIV/AIDS with Heterosexual transmission in the presence of treatment was examine in this paper, it ascertained the impact of treated individuals on the transmission dynamics of HIV/AIDS. Equilibrium points of the model system were found, stability analysis and numerical simulation were carried out, it was discovered that HIV/AIDS can die out with test of time as Ro < 1 . It was observed that the model had a disease free equilibrium which was asymptotically stable for Ro < 1 and unstable for Ro > 1. Graphical representations of the numerical analysis showing the effect of treatment on the model were also presented.

scholarly journals Demographic Features of Identified PLWHA Infected through Commercial and Nonmarital Noncommercial Heterosexual Contact in China from 2015 – 2018: A Retrospective Cross-Sectional Study

2020 ◽  
Author(s):  
Zhilong Dong ◽  
Liying Ma ◽  
Chang Cai ◽  
George Fu Gao ◽  
Fan Lyu
Keyword(s):  
Marital Status ◽  
Educational Level ◽  
Hiv Transmission ◽  
Cross Sectional Study ◽  
Demographic Characteristics ◽  
Heterosexual Transmission ◽  
People Living With Hiv ◽  
Heterosexual Contact ◽  
Cross Sectional ◽  
Hiv Aids

Abstract Background:Understanding the demographic characteristics of people living with HIV/AIDS (PLWHA) infected through commercial heterosexual contact (CHC) or nonmarital noncommercial heterosexual contact (NMNCHC) is important for HIV/AIDS prevention and control.Methods:Cases reported through the Chinese HIV/AIDS Case Reporting System (CRS) from 2015 to 2018 were analyzed. A descriptive and preliminary inferential analysis were performed for those demographic characteristics deemed of interest.Results:Overall, 523,121 identified PLWHA between 2015 and 2018 in the CRS were analyzed. The constituent ratio of heterosexual transmission increased from 66.25% in 2015 to 71.48% in 2018. The proportion of CHC heterosexual transmission decreased from 40.18% in 2015 to 37.99% in 2018, while that of NMNCHC increased from 46.33% in 2015 to 49.02% in 2018. PLWHA infected through NMNCHC were significantly younger than those who were infected through CHC (Student’s t test, P<0.0001), with an average age gap ranging from 5.63 (2015) to 7.46 (2018) years, and the average age of both groups increased annually. The frequency of newly identified PLWHA who were infected through CHC had a remarkable increase among the ages of 65 and above. Gender distribution was significantly different between CHC and NMNCHC (χ2 = 8909.00(2015), 9941.90(2016), 11004.00 (2017), 12836.00(2018), all P < 0.0001), and the ratio of men to women in the NMCHC group was 1.50:1 (2015), 1.51:1 (2016), 1.54:1 (2017), and 1.52:1 (2018), while in the commercial heterosexual contact (CHC) group, these ratios were 11.45:1 (2015), 12.08:1 (2016), 12.53:1 (2017), and 13.28:1 (2018). Marital status was significantly different between CHC and NMNCHC (χ2 = 94.67 (2015), 109.88(2016), 58.18(2017), 152.38(2018), all P < 0.0001). As the educational level improved, the proportion of NMNCHC also increased (Cochran - Armitage test, P<0.0001).Conclusions:We found that heterosexual transmission was the primary mode of HIV transmission in China from 2015 to 2018. PLWHA infected through CHC and NMNCHC had different characteristics in age, gender, marital status, and educational level. The frequency of PLWHA infected through CHC increased substantially in the age group of 65 and above. This study provides useful baseline data for future studies on the heterosexual transmission of HIV in China.

Characterization of Damping and Beating Effects Within the Aggregate Power Demand of Heterogeneous Thermostatically Controlled Loads

2015 ◽  
Author(s):  
Donald J. Docimo ◽  
Hosam K. Fathy
Keyword(s):  
Population Heterogeneity ◽  
Parameter Distribution ◽  
Population Parameter ◽  
Control Input ◽  
Power Demand ◽  
Response Dynamics ◽  
Parameter Heterogeneity ◽  
Thermostatically Controlled Loads ◽  
Aggregate Dynamics

This paper presents an analysis of the damping and beating effects within the aggregate power demand of heterogeneous thermostatically controlled loads (TCLs). Demand response using TCLs is an appealing method to enable higher levels of penetration of intermittent renewable resources into the electric grid. Previous literature covers the benefits of TCL population heterogeneity for control purposes, but the focus is solely on the damping observed in these systems. This work is, to the best of the authors’ knowledge, the first to characterize the combined damping and beating response of power demand versus the level of TCL population parameter heterogeneity. The forced aggregate dynamics of TCLs have been shown to be bilinear when set point temperature adjustment is used as a control input. This motivates the paper’s use of free response dynamics, which are linear, to characterize both the damping and beating phenomena. A stochastic parameter distribution is applied to the homogeneous power demand solution, furnishing an analytic expression for aggregate power demand. The resulting analysis shows that increasing parameter heterogeneity increases damping and shortens the beat period.

scholarly journals Optimal Control of HIV/AIDS in the Workplace in the Presence of Careless Individuals

2014 ◽  
Vol 2014 ◽  
pp. 1-19 ◽  
Author(s):  
Baba Seidu ◽  
Oluwole D. Makinde
Keyword(s):  
Optimal Control ◽  
Optimal Control Problem ◽  
Control Problem ◽  
Control Strategies ◽  
Nonlinear Dynamical System ◽  
Basic Reproductive Number ◽  
Reproductive Number ◽  
Nonlinear Dynamical ◽  
Basic Model ◽  
Hiv Aids

A nonlinear dynamical system is proposed and qualitatively analyzed to study the dynamics of HIV/AIDS in the workplace. The disease-free equilibrium point of the model is shown to be locally asymptotically stable if the basic reproductive number,R0, is less than unity and the model is shown to exhibit a unique endemic equilibrium when the basic reproductive number is greater than unity. It is shown that, in the absence of recruitment of infectives, the disease is eradicated whenR0<1, whiles the disease is shown to persist in the presence of recruitment of infected persons. The basic model is extended to include control efforts aimed at reducing infection, irresponsibility, and nonproductivity at the workplace. This leads to an optimal control problem which is qualitatively analyzed using Pontryagin’s Maximum Principle (PMP). Numerical simulation of the resulting optimal control problem is carried out to gain quantitative insights into the implications of the model. The simulation reveals that a multifaceted approach to the fight against the disease is more effective than single control strategies.

Soft computing framework for modelling transmission dynamics of HIV/AIDS under combined use of male and female condoms in heterosexual populations of Taraba State

2020 ◽  
Vol 26 (1) ◽  
Author(s):  
B.Y. Baha
Keyword(s):  
Genetic Algorithm ◽  
Soft Computing ◽  
Female Condom ◽  
Sub Saharan Africa ◽  
Transmission Dynamics ◽  
Male And Female ◽  
Combined Use ◽  
Computing Framework ◽  
Female Condoms ◽  
Hiv Aids

The widespread of HIV/AIDS has continued to constitute serious health and socioeconomic challenges for more than two decades, especially in sub-Saharan Africa. A permanent cure for this pandemic is not yet established and the issue of abstinence or faithfulness to sexual partners seems to be very difficult. This study used Genetic Agorithm of Soft Computing Framework for Modelling Transmission Dynamics of HIV/AIDS under combined use of male and female condoms in heterosexual populations of Taraba State. A total of 761 questionnaires were distributed to HIV/AIDS patients in the three senatorial zones of Taraba State. The researcher identified four set of terminals as independent variables: Never used condom, Used condom occasionally, Used condom most of the time, and Used condom all of the time. These values were converted to binary and coded as chromosomes into three fold: Male use of condom, Female use of condom, and Male and Female use of condom. The coded chromosomes of each category formed set of target values into the simulation of the Genetic algorithm. The simulation revealed that eradication of HIV/AIDS is obtainable in 6 generations with the use of male condom, 4 generations with the use of female condom and 2 generations with the use of both male and female condoms. The study also revealed that 56.4% of the respondents were female, 34.6% were male, 61.23% never used condom and 22.34% used condom all the times. This shows that there is no awareness on the use of female condom in Taraba State and probably the neighbouring states or Nigeria at large. The study recommended, among others, the use of both male and female condoms together as the best measure to achieve HIV/AIDS eradication in finite time.Keywords: Genetic Algorithm, HIV/AIDS transmission, Male and Female Condoms, Soft computing, Taraba StateVol. 26, No. 1, June 2019

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