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Johor Bahru, Malaysia

Yaakob N.H.,University of Technology Malaysia | Wagiran H.,University of Technology Malaysia | Imam Hossain M.,University of Technology Malaysia | Imam Hossain M.,Bangladesh University | And 3 more authors.
Applied Radiation and Isotopes | Year: 2011

We have investigated the thermoluminescent response and fading characteristics of germanium- and aluminium-doped SiO2 optical fibres. These optical fibres were placed in a solid phantom and irradiated using 6 and 10MV photon beams at doses ranging from 0.02 to 0.24Gy delivered using a linear accelerator. In fading studies, the TL measurements were continued up to 14 days post-irradation. We have investigated the linearity of TL response as a function of dose for Ge-, Al-doped optical fibre and TLD-100 obtained for 6 and 10MV photon irradiations. We have concentrated on doses that represent a small fraction of that delivered to the tumour to establish sensitivity of measurement for peripheral exposures in external beam radiotherapy. © 2011 Elsevier Ltd.

Sahini M.H.,University of Technology Malaysia | Wagiran H.,University of Technology Malaysia | Hossain I.,King Abdulaziz University | Saeed M.A.,University of Technology Malaysia | Ali H.,Hospital Sultan Ismail
Indian Journal of Physics | Year: 2014

This paper reports thermoluminescence characteristics of thermoluminescence dosimetry 100 chips and Yb-Tb-doped optical fibers irradiated with 6 and 10 MV photons. Thermoluminescence response of both dosimeters increases over a wide photon dose range from 0.5 to 4 Gy. Yb-Tb-doped optical fibers demonstrate useful thermoluminescence properties and represent a good candidate for thermoluminescence dosimetry application with ionizing radiation. The results of this fiber have been compared with those of commercially available standard thermoluminescence dosimetry-100 media. Commercially available Yb-Tb-doped optical fibers and said standard media are found to yield a linear relationship between dose- and thermoluminescence signal, although Yb-Tb-doped optical fibers provide only 10 % of the sensitivity of thermoluminescence dosimetry-100. With better thermoluminescence characteristics such as small size (125 μm diameter), high flexibility, easy of handling and low cost, as compared to other thermoluminescence materials, indicate that commercial Yb-Tb-doped optical fiber is a promising thermoluminescence material for variety of applications. © 2014 Indian Association for the Cultivation of Science.

Sahini M.H.,University of Technology Malaysia | Hossain I.,King Abdulaziz University | Wagiran H.,University of Technology Malaysia | Saeed M.A.,University of Technology Malaysia | Ali H.,Hospital Sultan Ismail
Applied Radiation and Isotopes | Year: 2014

Characteristics of the thermoluminescence (TL) responses of Yb- and Yb-Tb-doped optical fibers irradiated with 6. MV photons are reported. The concentration of Yb in the Yb-doped optical fiber was 0.26. mol%; the concentrations of Yb and Tb in the Yb-Tb-doped optical fiber were 0.62 and 0.2. mol%, respectively. The TL dose responses are linear in the dose range 0.5-4. Gy. The radiation sensitivity of the Yb-Tb material is almost two orders of magnitude higher than the sensitivity of the material doped with Yb alone. © 2014 Elsevier Ltd.

Momtaz Y.A.,University Putra Malaysia | Hamid T.A.,University Putra Malaysia | Yusoff S.,Hospital Sultan Ismail | Ibrahim R.,University Putra Malaysia
Gerontology | Year: 2013

Introduction: Research shows marked differences in the prevalence of dementia among different ethnic groups. However, there is a relative dearth of studies focusing on how ethnicity may influence dementia. The main aim of the current study is to test potential mediating effects of depression and level of education on the association between ethnicity and dementia. Methods: The sample for this study, consisting of 2,796 community-dwelling elderly people aged 60 years and older, was drawn from a cross-sectional national survey entitled 'Mental Health and Quality of Life of Older Malaysians'. The Malaysian adapted version of the Geriatric Mental State-Automated Geriatric Examination for Computer-Assisted Taxonomy was used to assess dementia and depression. Data analysis was conducted using IBM SPSS version 19. Results: As expected, the result of the χ2 analysis revealed significant ethnic difference in the prevalence of dementia (χ2 = 58.05, p ≤ 0.001). The results of the mediational analyses revealed that depression (Z = 4.05, p ≤ 0.001) and education (Z = 2.78, p ≤ 0.01) significantly, but partially, mediate the association between ethnicity and dementia. This suggests that disparities of depressive symptoms and education contribute to ethnic difference in the prevalence of dementia. Conclusions: These findings provide more insight into how ethnicity may influence an individual's vulnerability to dementia. The limitations of the study along with implications of the findings and needs for further study are discussed. Copyright © 2012 S. Karger AG, Basel.

Ahmad S.M.,Hospital Sultan Ismail | Syed Aznal S.S.,International Medical University | Tham S.W.,Hospital Besar Melaka
Malaysian Family Physician | Year: 2015

Objective: The objective of this paper was to determine the prevalence of overactive bladder syndrome (OABS) and its risk factors among patients with other gynaecological problems. Methods: This study was conducted on women aged more than 18 years who attended the gynaecology clinic for various diagnoses other than urinary problems at a tertiary hospital in Negeri Sembilan, Malaysia, for a period of 6 months. Data on patient’s profile, symptoms and risk factors for overactive bladder (OAB) were prospectively collected using a structured questionnaire adapted from ICIQ (international consultation on incontinence questionnaire). Exclusion criteria included patients with confirmed diagnosis of stress incontinence or OAB, neurological impairment, gynaecological malignancy and those with a previous history of pelvic radiation. Chi-square test and logistic regression test were used in the statistical analysis. We presented the odds ratio (OR) and 95% confidence interval for each of the OAB symptoms with p-value of 0.05. Results: The prevalence of OAB among the patients (n = 573) in this study was 19.1%. History of giving births to macrosomic babies and presence of utero-vaginal prolapse (UVP) were shown to be significantly associated with OAB in the multivariate analysis. Other factors were advanced age, high parity and menopausal for more than 5 years. More than half of the patients with the symptoms of OAB did not seek treatment, as they did not think it is necessary. Conclusion: It is found that the prevalence of OAB is similar with many other studies conducted elsewhere. It was found to be multifactorial, but was highly significantly related with the presence of UVP, especially cystocoele and history of giving births to macrosomic babies. © Academy of Family Physicians of Malaysia. All Rights Reserved.

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