Australian Journal of Basic and Applied Sciences

September 2022


Analysis of an SEIR model with the vertical transmission on transmission and spread of hepatitis B in Ghana

Kwaafo Akoto Awuah-Mensaha, Ute Muellerb, Steven Richardsonc

ABSTRACT: Lack of good quality information about hepatitis B (HB) is a major hindrance to policy direction and comprehensive implementation of interventions to prevent and control the disease in the endemic region of Sub-Saharan Africa (SSA), particularly Ghana. A SEIR deterministic compartmental model which incorporates latent period and vertical transmission, and applied to HB incidence data was used to examine the transmission and spread of HB in order to inform policy decision on prevention and control of the disease in a population. The model parameters were estimated by a unique hybrid optimisation method involving Genetic Algorithm and Levenberg Marquardt Algorithm using MATLAB (version R2018a). Based on the estimated parameters, the epidemiological threshold parameter R_0 was calculated to determine the prediction of the disease. The model was found to have a disease-free equilibrium that is globally asymptotically stable when the epidemiological threshold parameter R_0≤1, and an unique endemic equilibrium that is asymptotically stable when R_0>1. Stability of the model was discussed in terms of proportions of the state variables, where disease eradication or persistence meant the total infected proportions e+i vanished or uniformly persisted respectively with time. The threshold parameter, based on the estimated parameters, was calculated to be R_0=1.6854, which indicated that HB persists in the population. The endemic equilibrium state Q^*=(0.5741,0.0706,0.3553) was stable with total infected proportion 0.4.3 of the population uniformly persisting with time. Vertical transmission was found to be the major drive to transmission and spread of HB, compared with other parameters, and achieving a herd immunity threshold H=0.4067 of the population would keep the disease under control. The study also revealed that latent period is important in modelling HB.

[ FULL TEXT PDF 1-11 ] DOI: 10.22587/ajbas.2022.16.9.1


Different approaches for using Shalstab model to support climatic risk management in power transmission assets: Case study in a transmission line located in Serra do Mar Paranaense, Brazil

Jéssica Gerente, Edna Lindaura Luiz, Francisco Caruso Gomes Junior, Lucas Antonio Providelo, Guilherme Marchiori, Feliphe Augusto de Lima Andreoli, Daniel Colinques Palfi

ABSTRACT: The goal of this paper is to evaluate the usage of the Shalstab model in the diagnoses of the susceptibility to movements of mass in a Brazilian region through which a transmission line passes. The model is considered using two approaches: i) the classic approach, that is, obtaining a level of the terrain’s risk from the log(q/t) ratio and, ii) an approach based in relation to the critical daily rainfall values required to determine a rupture. For the parametrization of the geotechnical values required as Shalstab input, a spatialised approach was adopted which considers the lithological variability, since the study area it is located in an ancient fold belt structure. The movement of mass scars used for the validation of results indicate that the model’s risk level approach can identify the susceptible areas with a good accuracy. In relation to the critical amount of rainfall to cause ruptures in the study area, precipitations above 100mm/day are dangerous for around 10% of the study area. This precipitation value is very common in the region, which indicates the need for attention, since the transmission line’s structures may be hit by ruptures, passage zones and the deposition of movements of mass occurring there.

[ FULL TEXT PDF 12-21 ] DOI: 10.22587/ajbas.2022.16.9.2


Perception towards Psychological Flexibility Treatment by Parents of Young People with Chronic Pain

Jia Hang Lim, Sook Huey Lee

ABSTRACT: Chronic pain in young people leads to the suffering of the individual and their family members. It has become a significant concern as it causes negative consequences for adolescents. A questionnaire study was conducted to better understand parental attitudes toward such intervention for themselves and their chronic pain children. The study aims to understand parental perception towards such intervention for themselves and their children with chronic pain. This study is in line with the "Pain as the 5th Vital Sign" program promoted by the Malaysian Ministry of Health in 2008 to ensure that patients' pain is effectively managed. Parents were recruited via purposeful sampling and completed a web-based questionnaire. The questionnaire consisted of brief descriptions of ACT for chronic pain and asked parents to rate their preferences for treatment modes, perception of the effectiveness of the program, and their motivation and barriers to joining the proposed program. Descriptive analysis of 48 participants showed that parents preferred face-to-face (79.2%) compared to the online method (20.8%), individual sessions (52.1%) compared to group sessions (47.9%), and continuous (72.9%) compared to intermittent (25%) sessions. Most participants (62.6%) believed the treatment would be effective. A high percentage (91.7%) of participants reported being motivated to attend the program. The findings contribute to the lack of studies dealing with intervention for adolescents suffering from chronic pain in Malaysia. This study suggests that Malaysian parents of children with chronic pain conditions are open to ACT intervention targeting psychological flexibility and a contextualized treatment protocol should be developed and tested.

[ FULL TEXT PDF 22-27 ] DOI: 10.22587/ajbas.2022.16.9.3