MyMedR

Displaying all 11 publications

Abstract:

Sort:

Fulltext Car annual vehicle kilometer travelled estimated from car manufacturer data – an improved method

Shabadin, A., Megat Johari, N., Mohamed Jamil, H.

Pertanika Journal of Science & Technology, 2017;25(1):171-180.
MyJurnal

In 2013, 632 602 private cars were involved in road crashes, this amounting to 64% of all road crashes on
Malaysian roads. Risk is often used to quantifying the level of road safety whilst exposure is an essential
component of risk measurement. The calculation of VKT (vehicle kilometre travel) in this study using
odometer reading data obtained from automobile manufacturer is used for cars. This average in 2013
was 24,129 kilometres, the highest recorded in Selangor with 28,575 kilometres and the lowest at
16,342 kilometres a year, in Johor. This method is believed to be reliable with a high yielding number
of samples as well as a good representative set of samples for Malaysia.
The reliability and process capability assessment of suspended growth sewage treatment plant in Melaka, Malaysia

Ishak A, Mohamad E, Hambali A, Johari NL

Water Sci Technol, 2022 Nov;86(9):2233-2247.
PMID: 36378177 DOI: 10.2166/wst.2022.360

This paper presents the promising method of synchronizing the Six Sigma and reliability analyses at 15 sewage treatment plants (STPs) operating in Melaka, Malaysia. Five different suspended growth treatment technologies in various capacities were investigated. The sequential batch reactor (SBR) and extended aeration activated sludge (EAAS) processes, conventional activated sludge (CAS), aerated lagoon (AL), and oxidation pond (OP) were compared using innovative Niku's treatment reliability and Six Sigma process capability method for biological oxygen demand (BOD5), chemical oxygen demand (COD), total suspended solids (TSS), oil and grease (O&G), and ammoniacal nitrogen (NH3-N) effluent parameters and justified the importance of understanding the lognormal behavior of the effluent parameters in interpreting the performance monitoring results and discharge compliance. The results showed that the SBR and EAAS systems relatively fulfilled the highest performance (>95%) compared to conventional systems to ensure the high quality of effluent discharge. Although the whole system is incapable of removing nutrients efficiently, ranging between 42.31% and 90.48%, may lead to eutrophication issues. Process modification and treatment control should become a critical priority in order to reduce variability, improve stability, and increase the efficiency of nutrient removal. These initiatives promote global sustainable development goals (SDGs) 2030 and the domestic water sector transformation (WST) 2040 by treatment cost reduction, improving environmental sustainability and guaranteeing social and health benefits.
Predictors of quality of life among hospitalized geriatric patients with diabetes mellitus upon discharge

Johari N, Manaf ZA, Ibrahim N, Shahar S, Mustafa N

Clin Interv Aging, 2016;11:1455-1461.
PMID: 27799751

PURPOSE: Diabetes mellitus is prevalent among older adults, and affects their quality of life. Furthermore, the number is growing as the elderly population increases. Thus, this study aims to explore the predictors of quality of life among hospitalized geriatric patients with diabetes mellitus upon discharge in Malaysia.
METHODS: A total of 110 hospitalized geriatric patients aged 60 years and older were selected using convenience sampling method in a cross-sectional study. Sociodemographic data and medical history were obtained from the medical records. Questionnaires were used during the in-person semistructured interviews, which were conducted in the wards. Linear regression analyses were used to determine the predictors of each domain of quality of life.
RESULTS: Multiple regression analysis showed that activities of daily living, depression, and appetite were the determinants of physical health domain of quality of life (R(2)=0.633, F(3, 67)=38.462; P<0.001), whereas depression and instrumental activities of daily living contributed to 55.8% of the variability in psychological domain (R(2)=0.558, F(2, 68)=42.953; P<0.001). Social support and cognitive status were the determinants of social relationship (R(2)=0.539, F(2, 68)=39.763; P<0.001) and also for the environmental domain of the quality of life (R(2)=0.496, F(2, 68)=33.403; P<0.001).
CONCLUSION: The findings indicated different predictors for each domain in the quality of life among hospitalized geriatric patients with diabetes mellitus. Nutritional, functional, and psychological aspects should be incorporated into rehabilitation support programs prior to discharge in order to improve patients' quality of life.
Fulltext Childhood burns at the Paediatric Institute Kuala Lumpur

Ibrahim SB, Omar MB, Gan EC, Rauf A, Johari NB, Yusof HB

Med J Malaysia, 1995 Sep;50(3):221-5.
PMID: 8926898

A prospective study of 94 burned children was carried out from January 1993 to October 1994. Scalding was the predominant cause of injury affecting mainly toddlers between 1 and 3 years old. Ninety-six per cent of the injuries occurred at home. There was 1 death following an 81% flame burns. An intense campaign to make parents aware of the hazards is required as almost all the injuries were preventable.
Fulltext Infant feeding concerns in times of natural disaster: lessons learned from the 2014 flood in Kelantan, Malaysia

Sulaiman Z, Mohamad N, Ismail TA, Johari N, Hussain NH

Asia Pac J Clin Nutr, 2016;25(3):625-30.
PMID: 27440698 DOI: 10.6133/apjcn.092015.08

The flood that hit Kelantan in December 2014 was the worst in Malaysian history. Women and their infants accounted for a large proportion of the people at risk who were badly affected, as almost half of the population in Kelantan was in the reproductive age group. This report serves to raise awareness that breastfeeding mothers and infants are a special population with unique needs during a disaster. Four of their concerns were identified during this massive flood: first, the negative impact of flood on infant nutritional status and their health; second, open space and lack of privacy for the mothers to breastfeed their babies comfortably at temporary shelters for flood victims; third, uncontrolled donations of infant formula, teats, and feeding bottles that are often received from many sources to promote formula feeding; and lastly, misconceptions related to breastfeeding production and quality that may be affected by the disaster. The susceptibility of women and their infant in a natural disaster enhances the benefits of promoting the breastfeeding rights of women. Women have the right to be supported which enables them to breastfeed. These can be achieved through monitoring the distribution of formula feeding, providing water, electricity and medical care for breastfeeding mothers and their infants. A multifaceted rescue mission team involving various agencies comprising of local government, including the health and nutrition departments, private or non-governmental organizations and individual volunteers have the potential to improve a satisfactory condition of women and infants affected by floods and other potential natural disasters.
Fulltext Reconstruction of Secondary Type Congenital Hallux Varus with Modification of the Farmer Technique for Cover of Skin Defect: Report of Three Cases

Sulaiman AR, Munajat I, M-Yusuf H, Nik-Jaffar N, Zarullail NH, Mohd EF, et al.

Malays Orthop J, 2019 Nov;13(3):72-76.
PMID: 31890115 DOI: 10.5704/MOJ.1911.013

The reconstruction of hallux varus deformity involves the release of contracted medial structure and realignment of the phalange, leaving a significant skin defect which requires cover. Farmer described proximal based rotational skin flap from the first web space to cover the defect. This technique may compromise the circulation to the flap and risk to the lateral digital vessels. We modified his technique to address these issues. We report a successful reconstruction using the Farmer's technique on one patient and a modified technique on three patients. We used the excess skin from the extra digit to cover the medial defect. We found this modified technique of skin cover safe without risk of injuring the neurovascular bundle. There was no recurrence of deformity at last foolow-up. All patients were able to wear normal shoes.
Fulltext Microstructural behavior of magnetorheological elastomer undergoing durability evaluation by stress relaxation

Johari MAF, Mazlan SA, Nasef MM, Ubaidillah U, Nordin NA, Aziz SAA, et al.

Sci Rep, 2021 May 25;11(1):10936.
PMID: 34035434 DOI: 10.1038/s41598-021-90484-0

The widespread use of magnetorheological elastomer (MRE) materials in various applications has yet to be limited due to the fact that there are substantial deficiencies in current experimental and theoretical research on its microstructural durability behavior. In this study, MRE composed of silicon rubber (SR) and 70 wt% of micron-sized carbonyl iron particles (CIP) was prepared and subjected to stress relaxation evaluation by torsional shear load. The microstructure and particle distribution of the obtained MRE was evaluated by a field emission scanning electron microscopy (FESEM). The influence of constant low strain at 0.01% is the continuing concern within the linear viscoelastic (LVE) region of MRE. Stress relaxation plays a significant role in the life cycle of MRE and revealed that storage modulus was reduced by 8.7%, normal force has weakened by 27%, and stress performance was reduced by 6.88% along approximately 84,000 s test duration time. This time scale was the longest ever reported being undertaken in the MRE stress relaxation study. Novel micro-mechanisms that responsible for the depleted performance of MRE was obtained by microstructurally observation using FESEM and in-phase mode of atomic force microscope (AFM). Attempts have been made to correlate strain localization produced by stress relaxation, with molecular deformation in MRE amorphous matrix. Exceptional attention was focused on the development of molecular slippage, disentanglement, microplasticity, microphase separation, and shear bands. The relation between these microstructural phenomena and the viscoelastic properties of MRE was diffusely defined and discussed. The presented MRE is homogeneous with uniform distribution of CIP. The most significant recent developments of systematic correlation between the effects of microstructural deformation and durability performance of MRE under stress relaxation has been observed and evaluated.
Exploring Malaysian mothers' plans on sleeping arrangement with their newborn

Chang CT, Shunmugam P, Abdul Aziz NA, Abdul Razak NS, Johari N, Mohamad N, et al.

J Paediatr Child Health, 2020 Mar;56(3):426-431.
PMID: 31654469 DOI: 10.1111/jpc.14646

AIM: Bed sharing is defined as a newborn sleeping in the same bed with an adult. Bed sharing may put the newborn at risk of suffocation due to accidental smothering.
METHODS: This was a quasi-experimental study conducted in a tertiary referral hospital. Healthy post-delivery Malaysian mothers were randomly selected and enrolled into the control or the intervention group. On the day of discharge, mothers in the intervention group were interviewed face-to-face in the post-natal ward on their plans for sleeping arrangement with their newborn. After the interview, mothers were advised not to bed share with their newborn and were given an educational leaflet on safe sleeping practices. One week after discharge, mothers in both groups were interviewed over the telephone regarding their actual sleeping arrangements with their newborn using the same questionnaire. Logistic regression was performed to determine factors associated with reduced bed sharing.
RESULTS: A total of 94 mothers and 95 mothers were recruited to the control and intervention group, respectively. The baseline bed-sharing prevalence was similar between groups: 60.6% in the control group and 61.1% in the interventional group. The proportion of mothers who bed shared with their newborn reduced from 61.1 to 37.9% after the intervention (P
Fulltext An Insight into Amorphous Shear Band in Magnetorheological Solid by Atomic Force Microscope

Johari MAF, Sarman AM, Mazlan SA, U U, Nordin NA, Abdul Aziz SA, et al.

Materials (Basel), 2021 Aug 05;14(16).
PMID: 34442907 DOI: 10.3390/ma14164384

Micro mechanism consideration is critical for gaining a thorough understanding of amorphous shear band behavior in magnetorheological (MR) solids, particularly those with viscoelastic matrices. Heretofore, the characteristics of shear bands in terms of formation, physical evolution, and response to stress distribution at the localized region have gone largely unnoticed and unexplored. Notwithstanding these limitations, atomic force microscopy (AFM) has been used to explore the nature of shear band deformation in MR materials during stress relaxation. Stress relaxation at a constant low strain of 0.01% and an oscillatory shear of defined test duration played a major role in the creation of the shear band. In this analysis, the localized area of the study defined shear bands as varying in size and dominantly deformed in the matrix with no evidence of inhibition by embedded carbonyl iron particles (CIPs). The association between the shear band and the adjacent zone was further studied using in-phase imaging of AFM tapping mode and demonstrated the presence of localized affected zone around the shear band. Taken together, the results provide important insights into the proposed shear band deformation zone (SBDZ). This study sheds a contemporary light on the contentious issue of amorphous shear band deformation behavior and makes several contributions to the current literature.
Fulltext Temperature Dependent on Mechanical and Rheological Properties of EPDM-Based Magnetorheological Elastomers Using Silica Nanoparticles

Rashid RZA, Yunus NA, Mazlan SA, Johari N, Aziz SAA, Nordin NA, et al.

Materials (Basel), 2022 Mar 31;15(7).
PMID: 35407889 DOI: 10.3390/ma15072556

Temperature is one of the most influential factors affecting the performance of elastomer matrix in magnetorheological elastomer (MRE). Previous studies have utilized silica as a reinforcing filler in polymer composite and as a coating material in MRE to improve the thermal stability of the base material. However, the usage of silica as an additive in the thermal stability of MRE has not been explored. Thus, in this study, the effect of silica as an additive on the temperature-dependent mechanical and rheological properties of ethylene propylene diene monomer (EPDM)-based MREs was investigated by using 30 wt.% carbonyl iron particles (CIPs) as the main filler, with different contents of silica nanoparticles (0 to 11 wt.%). The microstructure analysis was examined by using field-emission scanning electron microscopy (FESEM), while the thermal characterizations were studied by using a thermogravimetric analyzer and differential scanning calorimetry. The tensile properties were conducted by using Instron Universal Testing Machine in the absence of magnetic field at various temperatures. Meanwhile, the rheological properties were analyzed under oscillatory loadings in the influence of magnetic field, using a rotational rheometer at 25 to 65 °C. The results revealed that the temperature has diminished the interfacial interactions between filler and matrix, thus affecting the properties of MRE, where the tensile properties and MR effect decrease with increasing temperature. However, the presence of silica capable improved the thermal stability of EPDM-based MRE by enhancing the interactions between filler and matrix, thus reducing the interfacial defects when under the influence of temperature. Consequently, the incorporation of silica nanoparticles as an additive in EPDM-based MRE requires more exploration, since it has the potential to sustain the properties of MRE devices in a variety of temperature conditions. Thus, the study on the temperature-dependent mechanical and rheological properties of MRE is necessary, particularly regarding its practical applications.
Fulltext The Effect of Microparticles on the Storage Modulus and Durability Behavior of Magnetorheological Elastomer

Johari MAF, Mazlan SA, Nordin NA, Ubaidillah U, Aziz SAA, Nazmi N, et al.

Micromachines (Basel), 2021 Aug 11;12(8).
PMID: 34442570 DOI: 10.3390/mi12080948

This paper presents the effect of the micro-sized particles on the storage modulus and durability characteristics of magnetorheological elastomers (MREs). The initial phase of the investigation is to determine any associations among the microparticles' weight percent fraction (wt%), structure arrangement, and the storage modulus of MRE samples. In order to carry out this, both isotropic and anisotropic types of MRE samples consisting of the silicone rubber matrix and 50, 60, 70, 75, and 80 wt% microparticles of carbonyl iron fractions are prepared. It is identified from the magneto-rheometer that the increase in storage modulus and decrease in linear viscoelastic region limit are observed in varying consistency depending on wt% and particle arrangement. The consistency of this dependency feature is highlighted by superimposing all of the graphs plotted to create the proposed the samples' behavior model. In response to increasing magnetic stimulation, a sample of 70 wt% microparticles with an isotropic arrangement is found to be significant and stable. The experimentally defined fraction is then used for the durability test as the second phase of the investigation. During this phase, the durability evaluation is subjected to stress relaxation for an extended period of time. After undergoing durability testing, storage modulus performance is decreased by 0.7-13% at various magnetic stimulation levels. This result directly indicates that the storage modulus characteristics of different forms of MRE are sensitive to the different iron particle fractions' and microparticles' alignment. Therefore, important treatments to alter the storage modulus can be undertaken before the practical implementation to accommodate any desired performance of MRE itself and MRE application systems.

Filters

Please provide feedback to Administrator ([email protected])

External Links