Displaying all 14 publications

Abstract:
Sort:
  1. Kamarudin SH, Abdullah LC, Aung MM, Ratnam CT
    Polymers (Basel), 2020 Nov 06;12(11).
    PMID: 33171889 DOI: 10.3390/polym12112604
    New environmentally friendly plasticized poly(lactic acid) (PLA) kenaf biocomposites were obtained through a melt blending process from a combination of epoxidized jatropha oil, a type of nonedible vegetable oil material, and renewable plasticizer. The main objective of this study is to investigate the effect of the incorporation of epoxidized jatropha oil (EJO) as a plasticizer and alkaline treatment of kenaf fiber on the thermal properties of PLA/Kenaf/EJO biocomposites. Kenaf fiber was treated with 6% sodium hydroxide (NaOH) solution for 4 h. The thermal properties of the biocomposites were analyzed using a differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). It must be highlighted that the addition of EJO resulted in a decrease of glass transition temperature which aided PLA chain mobility in the blend as predicted. TGA demonstrated that the presence of treated kenaf fiber together with EJO in the blends reduced the rate of decomposition of PLA and enhanced the thermal stability of the blend. The treatment showed a rougher surface fiber in scanning electron microscopy (SEM) micrographs and had a greater mechanical locking with matrix, and this was further supported with Fourier-transform infrared spectroscopy (FTIR) analysis. Overall, the increasing content of EJO as a plasticizer has improved the thermal properties of PLA/Kenaf/EJO biocomposites.
  2. Jatau AI, Aung MM, Kamauzaman TH, Chedi BA, Sha'aban A, Rahman AF
    J Intercult Ethnopharmacol, 2016 Mar 2;5(2):191-7.
    PMID: 27104042 DOI: 10.5455/jice.20160223105521
    Many studies have been conducted in health-care settings with regards to complementary and alternative medicine (CAM) use among patients. However, information regarding CAM use among patients in the emergency department (ED) is scarce. The aim of this article was to conduct a systematic review of published studies with regards to CAM use among the ED patients. A literature search of published studies from inception to September 2015 was conducted using PubMed, Scopus, and manual search of the reference list. 18 studies that met the inclusion criteria were reviewed. The prevalence rate of CAM use among ED patients across the studies ranged of 1.4-68.1%. Herbal therapy was the sub-modality of CAM most commonly used and frequently implicated in CAM-related ED visits. Higher education, age, female gender, religious affiliation, and chronic diseases were the most frequent factors associated with CAM use among the ED patients. Over 80% of the ED physicians did not ask the patients about the CAM therapy. Similarly, 80% of the ED patients were ready to disclose CAM therapy to the ED physician. The prevalence rate of CAM use among patients at ED is high and is growing with the current increasing popularity, and it has been a reason for some of the ED visits. There is a need for the health-care professionals to receive training and always ask patients about CAM therapy to enable them provide appropriate medical care and prevent CAM-related adverse events.
  3. Rayung M, Aung MM, Su'ait MS, Chuah Abdullah L, Ahmad A, Lim HN
    ACS Omega, 2020 Jun 23;5(24):14267-14274.
    PMID: 32596563 DOI: 10.1021/acsomega.9b04348
    Biobased polymers are useful materials in substituting conventional petroleum-derived polymers because of their good properties, ready availability, and abundance in nature. This study reports a new jatropha oil-based gel polymer electrolyte (GPE) for use in dye-sensitized solar cells (DSSCs). The GPE was prepared by mixing jatropha oil-based polyurethane acrylate (PUA) with different concentrations of lithium iodide (LiI). The GPE was characterized by infrared spectroscopy, thermal analysis, lithium nuclear magnetic resonance analysis, electrochemical analysis, and photocurrent conversion efficiency. The highest room-temperature ionic conductivity of 1.88 × 10-4 S cm-1 was obtained at 20 wt % of LiI salt. Additionally, the temperature-dependent ionic conductivity of the GPE exhibited Arrhenius behavior with an activation energy of 0.42 eV and a pre-exponential factor of 1.56 × 103 S cm-1. The electrochemical stability study showed that the PUA GPE was stable up to 2.35 V. The thermal stability of the gel electrolyte showed an improvement after the addition of the salt, suggesting a strong intermolecular interaction between PUA and Li, which leads to polymer-salt complexation, as proven by Fourier transform infrared spectroscopy analysis. A DSSC has been assembled using the optimum ionic conductivity gel electrolyte which indicated 1.2% efficiency under 1 sun condition. Thus, the jatropha oil-based GPE demonstrated favorable properties that make it a promising alternative to petroleum-derived polymer electrolytes in DSSCs.
  4. Mudri NH, Abdullah LC, Aung MM, Salleh MZ, Awang Biak DR, Rayung M
    Polymers (Basel), 2020 Jul 03;12(7).
    PMID: 32635384 DOI: 10.3390/polym12071494
    Crude jatropha oil (JO) was modified to form jatropha oil-based polyol (JOL) via two steps in a chemical reaction known as epoxidation and hydroxylation. JOL was then reacted with isocyanates to produce JO-based polyurethane resin. In this study, two types of isocyanates, 2,4-toluene diisocyanate (2,4-TDI) and isophorone diisocyanate (IPDI) were introduced to produce JPUA-TDI and JPUA-IPDI respectively. 2,4-TDI is categorised as an aromatic isocyanate whilst IPDI is known as a cycloaliphatic isocyanate. Both JPUA-TDI and JPUA-IPDI were then end-capped by the acrylate functional group of 2-hydroxyethyl methacrylate (HEMA). The effects of that isocyanate structure were investigated for their physico, chemical and thermal properties. The changes of the functional groups during each synthesis step were monitored by FTIR analysis. The appearance of urethane peaks was observed at 1532 cm-1, 1718 cm-1 and 3369 cm-1 while acrylate peaks were detected at 815 cm-1 and 1663 cm-1 indicating that JPUA was successfully synthesised. It was found that the molar mass of JPUA-TDI was doubled compared to JPUA-IPDI. Each resin showed a similar degradation pattern analysed by thermal gravimetric analysis (TGA). For the mechanical properties, the JPUA-IPDI-based coating formulation exhibited a higher hardness value but poor adhesion compared to the JPUA-TDI-based coating formulation. Both types of jatropha-based polyurethane acrylate may potentially be used in an ultraviolet (UV) curing system specifically for clear coat surface applications to replace dependency on petroleum-based chemicals.
  5. Mudri NH, Abdullah LC, Aung MM, Biak DRA, Tajau R
    Polymers (Basel), 2021 Jul 28;13(15).
    PMID: 34372093 DOI: 10.3390/polym13152490
    Jatropha oil-based polyol (JOL) was prepared from crude Jatropha oil via an epoxidation and hydroxylation reaction. During the isocyanation step, two different types of diisocyanates; 2,4-toluene diisocyanate (2,4-TDI) and isophorone diisocyanate (IPDI), were introduced to produce Jatropha oil-based polyurethane acrylates (JPUA). The products were named JPUA-TDI and JPUA-IPDI, respectively. The success of the stepwise reactions of the resins was confirmed using 1H nuclear magnetic resonance (NMR) spectroscopy to support the Fourier-transform infrared (FTIR) spectroscopy analysis that was reported in the previous study. For JPUA-TDI, the presence of a signal at 7.94 ppm evidenced the possible side reactions between urethane linkages with secondary amine that resulted in an aryl-urea group (Ar-NH-COO-). Meanwhile, the peak of 2.89 ppm was assigned to the α-position of methylene to the carbamate (-CH2NHCOO) group in the JPUA-IPDI. From the rheological study, JO and JPUA-IPDI in pure form were classified as Newtonian fluids, while JPUA-TDI showed non-Newtonian behaviour with pseudoplastic or shear thinning behaviour at room temperature. At elevated temperatures, the JO, JPUA-IPDI mixture and JPUA-TDI mixture exhibited reductions in viscosity and shear stress as the shear rate increased. The JO and JPUA-IPDI mixture maintained Newtonian fluid behaviour at all temperature ranges. Meanwhile, the JPUA-TDI mixture showed shear thickening at 25 °C and shear thinning at 40 °C, 60 °C and 80 °C. The master curve graph based on the shear rate for the JO, JPUA-TDI mixture and JPUA-IPDI mixture at 25 °C, 40 °C, 60 °C and 80 °C was developed as a fluid behaviour reference for future storage and processing conditions during the encapsulation process. The encapsulation process can be conducted to fabricate a self-healing coating based on a microcapsule triggered either by air or ultra-violet (UV) radiation.
  6. Taung Mai LL, Aung MM, Muhamad Saidi SA, H'ng PS, Rayung M, Jaafar AM
    Polymers (Basel), 2021 Jun 30;13(13).
    PMID: 34209121 DOI: 10.3390/polym13132177
    The use of bio-based polymers in place of conventional polymers gives positives effects in the sense of reduction of environmental impacts and the offsetting of petroleum consumption. As such, in this study, jatropha oil was used to prepare epoxidized jatropha oil (EJO) by the epoxidation method. The EJO was used to prepare a shape memory polymer (SMP) by mixing it with the curing agent 4-methylhexahydrophthalic anhydride (MHPA) and a tetraethylammonium bromide (TEAB) catalyst. The resulting bio-based polymer is slightly transparent and brown in color. It has soft and flexible properties resulting from the aliphatic chain in jatropha oil. The functionality of SMP was analyzed by Fourier transform infrared (FTIR) spectroscopy analysis. The thermal behavior of the SMP was measured by thermogravimetric analysis (TGA), and it showed that the samples were thermally stable up to 150 °C. Moreover, the glass transition temperature characteristic was obtained using differential scanning calorimetry (DSC) analysis. The shape memory recovery behavior was investigated. Overall, EJO/MHPA was prepared by a relatively simple method and showed good shape recovery properties.
  7. Chai KL, Aung MM, Noor IM, Lim HN, Abdullah LC
    Sci Rep, 2022 Jan 07;12(1):124.
    PMID: 34997013 DOI: 10.1038/s41598-021-03965-7
    Jatropha oil-based polyurethane acylate gel polymer electrolyte was mixed with different concentrations of tetrabutylammonium iodide salt (TBAI). The temperature dependences of ionic conductivity, dielectric modulus and relaxation time were studied in the range of 298 to 393 K. The highest ionic conductivity of (1.88 ± 0.020) × 10-4 Scm-1 at 298 K was achieved when the gel contained 30 wt% of TBAI and 2.06 wt% of I2. Furthermore, the study found that conductivity-temperature dependence followed the Vogel-Tammann Fulcher equation. From that, it could be clearly observed that 30 wt% TBAI indicated the lowest activation energy of 6.947 kJ mol-1. By using the fitting method on the Nyquist plot, the number density, mobility and diffusion coefficient of the charge carrier were determined. The charge properties were analysed using the dielectric permittivity, modulus and dissipation factor. Apart from this, the stoke drag and capacitance were determined.
  8. Jatau AI, Aung MM, Kamauzaman TH, Rahman AF
    Drugs Real World Outcomes, 2015 10 23;2(4):387-395.
    PMID: 26689834 DOI: 10.1007/s40801-015-0045-2
    BACKGROUND: Data on the prevalence of adverse drug event (ADE)-related emergency department (ED) visits in developing countries are limited. Malaysia is located in South-East Asia, and, to our knowledge, no information exists on ADE-related ED visits.

    OBJECTIVE: The objective of this study was to determine the prevalence, preventability, severity, and outcome of drug-related ED visits.

    METHODOLOGY: A cross-sectional study was conducted in consenting patients who visited the ED of Hospital Universiti Sains Malaysia over a 6-week period. The ED physician on duty determined whether or not the visit was drug related according to set criteria. Other relevant information was extracted from the patient's medical folder by a clinical pharmacist.

    RESULTS: Of the 434 consenting patients, 133 (30.6 %; 95 % confidence interval [CI] 26-35 %) visits were determined to be ADE related; 55.5 % were considered preventable, 11.3 % possibly preventable, and 33.1 % not preventable. Severity was classed as mild in 1.5 %, moderate in 67.7 %, and severe in 30.8 %. The most common ADEs reported were drug therapeutic failure (55.6 %) and adverse drug reactions (32.3 %). The most frequently implicated drugs were antidiabetics (n = 31; 23.3 %), antihypertensives (n = 28; 21.1 %), antibiotics (n = 13; 9.8 %), and anti-asthmatics (n = 11; 8.3 %). A total of 93 patients (69.9 %) were admitted to the ED for observation, 25 (18.8 %) were discharged immediately after consultation, and 15 (11.3 %) were admitted to the ward through the ED.

    CONCLUSION: The prevalence of ADE-related ED visits was high; more than one-half of the events were considered preventable and one-third was classed as severe. As such, preventive measures will minimize future occurrences and increase patient safety.
  9. Saalah S, Abdullah LC, Aung MM, Salleh MZ, Awang Biak DR, Basri M, et al.
    Polymers (Basel), 2021 Mar 05;13(5).
    PMID: 33807622 DOI: 10.3390/polym13050795
    Nowadays, there is a significant trend away from solvent-based polyurethane systems towards waterborne polyurethane dispersions due to government regulations requiring manufacturers to lower total volatile organic compounds, as well as consumer preference for more environmentally friendly products. In this work, a renewable vegetable oil-based polyol derived from jatropha oil was polymerized with isophorone diisocyanate and dimethylol propionic acid to produce anionic waterborne polyurethane dispersion. Free standing films with up to 62 wt.% bio-based content were successfully produced after evaporation of water from the jatropha oil-based waterborne polyurethane (JPU) dispersion, which indicated good film formation. The chemical and thermo-mechanical properties of the JPU films were characterized. By increasing the OH numbers of polyol from 161 mgKOH/g to 217 mgKOH/g, the crosslinking density of the JPU was significantly increased, which lead to a better storage modulus and improved hydrophobicity. Overall, JPU produced from polyol having OH number of 217 mgKOH/g appears to be a promising product for application as a binder for wood and decorative coatings.
  10. Tuan Naiwi TSR, Aung MM, Ahmad A, Rayung M, Su'ait MS, Yusof NA, et al.
    Polymers (Basel), 2018 Oct 12;10(10).
    PMID: 30961067 DOI: 10.3390/polym10101142
    Polyurethane acrylate (PUA) from vegetable oil has been synthesized and prepared for solid polymer electrolyte. Polyol has been end-capped with Toluene 2,4-Diisocyanate (TDI) followed by hydroxylethylmethylacrylate (HEMA) in a urethanation process to produce PUA. The mixtures were cured to make thin polymeric films under UV radiation to produce excellent cured films which exhibit good thermal stability and obtain high ionic conductivity value. 3 to 15 wt. % of ethylene carbonate (EC) mixed with 25 wt. % LiClO₄ was added to PUA to obtain PUA electrolyte systems. PUA modified with plasticizer EC 9 wt. % achieved the highest conductivity of 7.86 × 10-4 S/cm, and relatively improved the linear sweep voltammetry, transference number and dielectric properties. Fourier Transform Infrared Spectroscopy (FTIR) and dielectric analysis were presented. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), followed by X-ray Diffraction (XRD) and morphology have been studied. The addition of plasticizer to the polyurethane acrylate shows significant improvement in terms of the conductivity and performance of the polymer electrolyte.
  11. Wafa SW, Shahril MR, Ahmad AB, Zainuddin LR, Ismail KF, Aung MM, et al.
    PMID: 27146199 DOI: 10.1186/s12955-016-0474-y
    Research suggests that physical activity plays a role to improve health related- quality of life (QoL), however studies examining the association between physical activity and HRQOL are limited in the paediatric literature. The aim of this study is to explore the relationship between physical activity and HRQoL among Malaysian children.
  12. Ibrahim MS, Naing NN, Abd Aziz A, Makhtar M, Mohamed Yusoff H, Esa NK, et al.
    Int J Environ Res Public Health, 2022 Dec 10;19(24).
    PMID: 36554487 DOI: 10.3390/ijerph192416601
    During the initial phase of the coronavirus disease 2019 (COVID-19) pandemic, there was a critical need to create a valid and reliable screening and surveillance for university staff and students. Consequently, 11 medical experts participated in this cross-sectional study to judge three risk categories of either low, medium, or high, for all 1536 possible combinations of 11 key COVID-19 predictors. The independent experts' judgement on each combination was recorded via a novel dashboard-based rating method which presented combinations of these predictors in a dynamic display within Microsoft Excel. The validated instrument also incorporated an innovative algorithm-derived deduction for efficient rating tasks. The results of the study revealed an ordinal-weighted agreement coefficient of 0.81 (0.79 to 0.82, p-value < 0.001) that reached a substantial class of inferential benchmarking. Meanwhile, on average, the novel algorithm eliminated 76.0% of rating tasks by deducing risk categories based on experts' ratings for prior combinations. As a result, this study reported a valid, complete, practical, and efficient method for COVID-19 health screening via a reliable combinatorial-based experts' judgement. The new method to risk assessment may also prove applicable for wider fields of practice whenever a high-stakes decision-making relies on experts' agreement on combinations of important criteria.
  13. Mahachai V, Vilaichone RK, Pittayanon R, Rojborwonwitaya J, Leelakusolvong S, Maneerattanaporn M, et al.
    J Gastroenterol Hepatol, 2018 Jan;33(1):37-56.
    PMID: 28762251 DOI: 10.1111/jgh.13911
    Helicobacter pylori (H. pylori) infection remains to be the major cause of important upper gastrointestinal diseases such as chronic gastritis, peptic ulcer, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. H. pylori management in ASEAN: the Bangkok consensus report gathered key opinion leaders for the region to review and evaluate clinical aspects of H. pylori infection and to develop consensus statements, rationales, and grades of recommendation for the management of H. pylori infection in clinical practice in ASEAN countries. This ASEAN Consensus consisted of 34 international experts from 10 ASEAN countries, Japan, Taiwan, and the United States. The meeting mainly focused on four issues: (i) epidemiology and disease association; (ii) diagnostic tests; (iii) management; and (iv) follow-up after eradication. The final results of each workshop were presented for consensus voting by all participants. Statements, rationale, and recommendations were developed from the available current evidence to help clinicians in the diagnosis and treatment of H. pylori and its clinical diseases.
  14. Gaisberger H, Fremout T, Kettle CJ, Vinceti B, Kemalasari D, Kanchanarak T, et al.
    Conserv Biol, 2021 Dec 05.
    PMID: 34865262 DOI: 10.1111/cobi.13873
    Tree diversity in Asia's tropical and subtropical forests is central to nature-based solutions. Species vulnerability to multiple threats, which affect provision of ecosystem services, is poorly understood. We conducted a region-wide, spatially explicit assessment of the vulnerability of 63 socioeconomically important tree species to overexploitation, fire, overgrazing, habitat conversion, and climate change. Trees were selected for assessment from national priority lists, and selections were validated by an expert network representing 20 countries. We used Maxent suitability modeling to predict species distribution ranges, freely accessible spatial data sets to map threat exposures, and functional traits to estimate threat sensitivities. Species-specific vulnerability maps were created as the product of exposure maps and sensitivity estimates. Based on vulnerability to current threats and climate change, we identified priority areas for conservation and restoration. Overall, 74% of the most important areas for conservation of these trees fell outside protected areas, and all species were severely threatened across an average of 47% of their native ranges. The most imminent threats were overexploitation and habitat conversion; populations were severely threatened by these factors in an average of 24% and 16% of their ranges, respectively. Our model predicted limited overall climate change impacts, although some study species were likely to lose over 15% of their habitat by 2050 due to climate change. We pinpointed specific natural areas in Borneo rain forests as hotspots for in situ conservation of forest genetic resources, more than 82% of which fell outside designated protected areas. We also identified degraded areas in Western Ghats, Indochina dry forests, and Sumatran rain forests as hotspots for restoration, where planting or assisted natural regeneration will help conserve these species, and croplands in southern India and Thailand as potentially important agroforestry options. Our results highlight the need for regionally coordinated action for effective conservation and restoration.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links