Displaying publications 1 - 20 of 32 in total

Abstract:
Sort:
  1. Fulltext Validation of EuroSCORE II in patients undergoing coronary artery bypass grafting (CABG) surgery at the National Heart Institute, Kuala Lumpur: a retrospective review
    Musa AF, Cheong XP, Dillon J, Nordin RB
    F1000Res, 2018;7:534.
    PMID: 32913630 DOI: 10.12688/f1000research.14760.2
    Background: The European System for Cardiac Operative Risk (EuroSCORE) II was developed in 2011 to replace the aging EUROScore for predicting in-house mortality after cardiac surgery. Our aim was to validate EuroSCORE II in Malaysian patients undergoing coronary artery bypass graft (CABG) surgery at our Institute. Methods: A retrospective single-center study was performed. A database was created to include EuroSCORE II values and actual mortality of 1718 patients undergoing CABG surgery in Malaysia from 1st January to 31st December 2016. The goodness-of-fit of EuroSCORE II was determined by the Hosmer-Lemeshow goodness-of-fit test and discriminatory power with the areas under the receiver operating characteristics (ROC) curve (AUC). Results: Observed mortality rate was 4.66% (80 out of 1718 patients). The median EuroSCORE II value was 2.06% (Inter Quartile Range: 1.94%) (1st quartile: 1.45%, 3rd quartile: 3.39%). The AUC for EuroSCORE II was 0.7 (95% CI 0.640 - 0.759) indicating good discriminatory power. The Hosmer-Lemeshow goodness-of-fit test did not show significant difference between expected and observed mortality in accordance to the EuroSCORE II model (Chi-square = 13.758, p = 0.089) suggesting good calibration of the model in this population. Cross-tabulation analysis showed that there is slight overestimation of EuroSCORE II in low-risk groups (0-10%) and slight underestimation in high-risk groups (>20%). Multivariate logistic regression analysis showed that gender, age, total hospital stay, serum creatinine and critical pre-operative state are significant predictors of mortality post-CABG surgery. Conclusion: This study indicated that the EuroSCORE II is a good predictor of post-operative mortality in the context of Malaysian patients undergoing CABG surgery. Our study also showed that certain independent variables might possess higher weightage in predicting mortality among this patient group. Therefore, it is suggested that EuroSCORE II can be safely used for risk assessment while ideally, clinical consideration should be applied on an individual basis.
  2. Use of Fe₃O₄ Nanoparticles for Enhancement of Biosensor Response to the Herbicide 2,4-Dichlorophenoxyacetic Acid
    Loh KS, Lee YH, Musa A, Salmah AA, Zamri I
    Sensors (Basel), 2008 Sep 18;8(9):5775-5791.
    PMID: 27873839
    Magnetic nanoparticles of Fe₃O₄ were synthesized and characterized using transmission electron microscopy and X-ray diffraction. The Fe₃O₄ nanoparticles were found to have an average diameter of 5.48 ±1.37 nm. An electrochemical biosensor based on immobilized alkaline phosphatase (ALP) and Fe₃O₄ nanoparticles was studied. The amperometric biosensor was based on the reaction of ALP with the substrate ascorbic acid 2-phosphate (AA2P). The incorporation of the Fe₃O₄ nanoparticles together with ALP into a sol gel/chitosan biosensor membrane has led to the enhancement of the biosensor response, with an improved linear response range to the substrate AA2P (5-120 μM) and increased sensitivity. Using the inhibition property of the ALP, the biosensor was applied to the determination of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The use of Fe₃O₄ nanoparticles gives a two-fold improvement in the sensitivity towards 2,4-D, with a linear response range of 0.5-30 μgL-1. Exposure of the biosensor to other toxicants such as heavy metals demonstrated only slight interference from metals such as Hg2+, Cu2+, Ag2+ and Pb2+. The biosensor was shown to be useful for the determination of the herbicide 2, 4-D because good recovery of 95-100 percent was obtained, even though the analysis was performed in water samples with a complex matrix. Furthermore, the results from the analysis of 2,4-D in water samples using the biosensor correlated well with a HPLC method.
  3. Transduser optik hidrogen peroksida berasaskan enzim peroksidase terpegun dalam monolit hibrid sol-gel-kitosan
    Nurul Izzah Ab Rahman, Musa Ahmad
    Sains Malaysiana, 2006;35:7-10.
    Kajian pemegunan enzim peroksidase dalam membran hibrid sol-gel-kitosan untuk penyediaan transduser optik hidrogen peroksida telah dilakukan dalam pembinaan biosensor. Kajian ini merangkumi pengoptimuman nisbah sol-gel-kitosan, pencirian enzim dalam larutan bebas dan pemegunan enzim dalam hibrid sol-gel-kitosan serta penciriannya. Spektrum serapan bagi setiap pencirian ditentukan menggunakan Spektrofotometer uL-Nampak. Hasil kajian menunjukkan aktiviti enzim tidak berubah selepas pemegunan. Nisbah optimum hibrid sol-gel-kitosan adalah 4:6. Nilai sisihan piawai relatif (RSD) untuk kebolehulangan kaedah ini adalah 2.71% dan 3.76%, masing-masingnya untuk enzim bebas dan enzim terpegun.
  4. Fulltext The role of religion in mitigating the COVID-19 pandemic: the Malaysian multi-faith perspectives
    Tan MM, Musa AF, Su TT
    Health Promot Int, 2022 Feb 17;37(1).
    PMID: 33928389 DOI: 10.1093/heapro/daab041
    Social distancing is crucial in breaking the cycle of transmission of COVID-19. However, many religions require the faithful to congregate. In Malaysia, the number of COVID-19 cases spiked up from below 30 in February 2020 to more than a thousand a month later. The sudden increase was mostly linked to a large Islamic gathering attended by 16,000 near the capital, Kuala Lumpur. Another large COVID-19 cluster was from a church gathering in Kuching, Sarawak. Within a few weeks, Malaysia became the worst hit country by COVID-19 in Southeast Asia. While religious leaders have advised social distancing among their congregants, the belief that "God is our shield" is often cited for gathering. There is a need to promote sound decision-making among religious adherents so that they will not prioritize their loyalty to the subjective interpretation of religion over evidence-based medicine. Malaysia, a multi-cultural and multi-faith country, is an example of how religious beliefs could strongly influence health behaviours at individual and community levels. In this article, we detail the religious aspects of COVID-19 prevention and control in Malaysia and discuss the possible role of religious organizations in encouraging sound decision-making among religious adherents in mitigating this crisis. We make recommendations on how to promote a partnership between the healthcare system and religious organizations, and how religion and faith could be integrated into health promotion channels and resources in the response of COVID-19 and future communicable diseases.
  5. Fulltext The Malay version of SF-36 health survey instrument: testing data quality, scaling assumptions, reliability and validity in post-coronary artery bypass grafting (CABG) surgery patients at the National Heart Institute (Institut Jantung Negara-IJN), Kuala Lumpur
    Musa AF, Yasin MSM, Smith J, Yakub MA, Nordin RB
    Health Qual Life Outcomes, 2021 Feb 09;19(1):50.
    PMID: 33563262 DOI: 10.1186/s12955-020-01658-9
    BACKGROUND: The Short Form 36 (SF-36) is a scoring system comprising of 36 items categorized into eight constructs corresponding to patients' health-related quality of life. It has been used extensively in various countries on different sub-populations and used to indicate the health status and help to ascertain the effect of clinical interventions on the particular population.

    OBJECTIVE: To examine the psychometric properties of the Malay version of SF-36 (Malay SF-36) summated rating scales and validate the scale among post-coronary artery bypass grafting surgery (CABG) patients at the National Heart Institute (IJN), Kuala Lumpur.

    METHODS: Five hundred and nine post-CABG patients at the IJN, Malaysia completed the questionnaires between 1 July and 31 December 2017. Psychometric tests endorsed by the "International Quality of Life Assessment Project" were utilised.

    RESULTS: The data quality was excellent with a high questionnaire completion rate (100%). As hypothesized, the ordering of item means within scales was clustered. In unison, scaling assumptions were satisfied. Good discriminant validity was shown between subsets of patients with various levels of health status. Notwithstanding, there were probably translation issues of the Physical Functioning scale which showed small ceiling effects. We clearly observed high ceiling and floor effects in both Role Physical and Role Emotional scale most probably attributed to the dichotomous style of their choice of responses. Cronbach alpha values of the eight scales ranged from 0.73 to 0.90, showing good internal consistency reliability. Confirmatory Factor Analysis (CFA) confirmed the 8-factor solution and Composite Reliability revealed internal consistency reliability except for Vitality and Social Functioning. Based on the Average Variance Extracted (AVE), convergent validity was adequate except for two domains. Discriminant Validity is good for the eight constructs as the √AVE are generally higher than the correlation coefficients between the latent constructs.

    CONCLUSION: The scoring for the Malay SF-36 based on the summated ratings method was proven to be valid to be applied in our local clinical population. The CFA, fitness estimates, reliability and validity assessments suggest that the Malay version of SF36 is a valid and reliable instrument. However, further work is warranted to further refine the convergent validity and reliability of some scales.

  6. Quantitative determination of ammonium ion in aqueous environment using Riegler’s solution and artificial neural network
    Tan LL, Musa Ahmad, Lee YH
    Sains Malaysiana, 2011;40:1105-1113.
    A quantitative analysis has been conducted to determine the concentration of ammonium (NH4+) ion in solution by using Ultraviolet-visible spectrophotometry method and artificial neural network (ANN). Riegler’s reagent was used to form Riegler-NH4+ complex. The characterisations of Riegler’s reagent in solution such as photostability, pH effect, reagent concentration, dynamic range and reproducibility were conducted. The colour change of the Riegler’s reagent after reaction with NH4+ was yellow to red. The Riegler’s reagent responds linearly to NH4+ ion concentration in the range of 1-7 ppm with optimum response at pH7. Satisfactory reproducibility (2.0-2.8%) were obtained with this reagent. The effect of interfering ions that may contain in the leachate on the determination of NH4+ ion was also studied. The application of ANN enabled the extension of the useful dynamic concentration range of NH4+ ion to 1–24 ppm. The best ANN architecture for Riegler-NH4+ complex was built from 29 hidden neurons, 21,389 epochs number and 0.001% learning rate which produced sum square error (SSE) value of 0.0483 with an average calibration error of 1.4136.
  7. Prob Bolehbuang Berasaskan Gentian Optik untuk Analisis Ion Al (III) di dalam Air (Optical Fibre Based Disposable Probe to Analyze Al(III) Ion in Water)
    Musa Ahmad, Narayanaswamy R
    Sains Malaysiana, 1996;25.
    Optical fibre has been used in this study to guide a light from the light source to the probe. A disposable type probe developed in this study consist of a reagent Chrome Azurol S (CAS) immobilised on a polymeric support (XAD-2) which has been coupled to a fibre end using nylon mesh. This sensor was regenerable using fluoride solution with a limit of detection of 1.0 ´ 10-5 M, high reproducibility (relative error of < 5.0%) and can be used for Al(III) determination in water at concentration range of 1.3 ´ 10-5 M - 7.0 ´ 10-4 M. The results obtained using this sensor is comparable to the well established method such as atomic absorption spectrophotometry using graphite furnace. EDTA, phosphate, oxalate, tartrate, Cu(II), Fe(III), Be(II) and Ca(III) were found to interfere during Al(III) determination in water.
    Gentian optik telah digunakan di dalam kajilidikan ini sebagai pemandu cahaya daripada sumber cahaya kepada prob. Prob jenis bolehbuang yang dibina dalam kajian ini terdiri daripada reagen Chrome Azurol S (CAS) yang telah dipegunkan di atas penyokong polimer (XAD-2) dan dipegang olehjaring nilon. Penderia ini boleh dijanakan semula menggunakan larutan fluorida, mempunyai had pengesaran 1.0 ´ 10-5 M, kebolehulangan yang tinggi (ralat relatif < 5.0%) dan boleh digunakan untuk penentuan Al(III) dalam air pada julat kepekatan 1.3 ´ 10-5 M - 7.0 ´ 10-4 M. Keputusan analisis yang diperolehi menggunakan penderia ini adalah bolehbanding dengan kaedah yang telah diterima umum seperti spektrofotometri serapan atom mertggunakan relau grafit. EDTA, fosfat, oksalat, tartrat, Cu(II), Fe(III), Be(II) dan Ca(III) didapati menganggu semasa penentuan Al(III) di dalam air.
  8. Fulltext Primary osteosarcoma of the sphenoid wing in a middle-aged woman with extensive intracranial extension: A case report
    Ong WF, Musa AT, Ooi LW, Karim NKA
    J Taibah Univ Med Sci, 2021 Dec;16(6):943-947.
    PMID: 34899138 DOI: 10.1016/j.jtumed.2021.07.007
    Primary osteosarcomas involving the base of the skull in middle-aged patients are rare. We describe the case of a 59-year-old Asian woman presenting with lethargy, epistaxis, left maxillary and mandibular pain, and headache. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a large left greater sphenoid wing tumour with extensive local infiltration and intracranial extension. The tumour was diagnosed as osteosarcoma based on histological examination. In this report, we discuss the clinical presentations, radiological features, and imaging differential diagnoses of this case.
  9. Potensi reagen fenilfluoron sebagai penunjuk pH untuk pembangunan sensor optik pH
    Rosmawani Mohammad, Musa Ahmad, Jamaluddin Mohd Daud
    Sains Malaysiana, 2007;36:33-38.
    Potensi larutan reagen fenilfluoron untuk digunakan sebagai bahan reagen bagi pembangunan sensor optik pH dibincangkan dalam kajian ini. Reagen ini dipilih kerana ia belum pernah dilaporkan sebelum ini untuk digunakan sebagai bahan reagen bagi pembangunan sensor optik pH. Berdasarkan kajian larutan yang telah dijalankan, julat rangsangan linear pH bagi reagen fenilfluoron ialah antara pH 4–11. Perubahan warna dapat diperhatikan, iaitu warna kuning dalam asid kuat, warna oren dalam asid lemah serta bes lemah dan warna ungu dalam bes kuat. Perubahan warna yang berlaku adalah lebih kurang 5 saat. Reagen fenilfluoron mempunyai kestabilan foto yang baik dengan nilai RSD 0.33% untuk tempoh kajian selama 95 hari. Nilai RSD bagi kebolehulangan pada pH 2, pH 7 dan pH 12 adalah masing-masingnya sebanyak 2.6%, 0.9% dan 1.4%. Pemerhatian ini menunjukkan fenilfluoron mempunyai potensi yang baik untuk digunakan sebagai bahan reagen bagi pembangunan sensor optik pH.
  10. Peningkatan kesensitifan sensor Al(iii) optik dengan menggunakan manik terkandung polimer
    Faiz Bukhari Mohd Suah, Musa Ahmad, Lee YH
    Sains Malaysiana, 2016;45:1795-1805.
    Sensor Al(III) optik berasaskan prinsip pengukuran pantulan dengan menggunakan manik polimer terkandung polimer (PIMs) terpegun telah dibangunkan. Manik PIMs terpegun yang disediakan dalam kajian ini mengandungi manik poli(vinil klorida) (PVC), Aliquat 336, diositil pthalat (DOP) dan reagen eriokrom sianin R (ESR). Sensor yang menggunakan manik PIMs terpegun ini menunjukkan rangsangan yang lebih tinggi berbanding dengan sensor yang tidak menggunakan manik PIMs. Masa rangsangan sensor pula ditetapkan selepas 3 min dengan nilai pH optimum 6.0. Sensor Al(III) optik ini memberikan rangsangan linear pada julat 5.56×10-5 - 3.52×10-4 molL-1, dengan nilai had pengesanan terendah (LOD) yang dikira ialah 3.41×10-5 molL-1. Kajian validasi nilai ion Al(III) bagi beberapa sampel air semula jadi yang ditambah dengan ion Al(III) menggunakan sensor Al(III) optik yang dibangunkan dalam kajian ini, menunjukkan tiada perbezaan secara signifikan pada nilai ion Al(III) yang diperoleh apabila dibandingkan dengan keputusan yang diperoleh menggunakan spektrofotometer serapan atom konvensional.
  11. Penghibridan Bahan Sol-gel dan Kitosan sebagaiMatriks untuk Bahan Penderia Kimia (Hybridisation of Sol-Gel and Chitosan as Matrix for Chemical Sensing Material
    Musa Ahmad, Lau MY
    Sains Malaysiana, 2005;34.
    This study focused on the development and optimization of a hybrid material formed from sol-gel and chitosan which could be used as a chemical sensing material. It is hoped that this new matrix can overcome certain weaknesses in sol­gel and chitosan materials. Dip-coating technique was used to prepare the film on microscope glass slide which functioned as a solid support. For optimization purposes, thymol blue was chosen as a pH indicator and was entrapped in the film. The film was characterized using uv-Visible Spectrophotometer. Morphology studies of the surface of the film were carried out using Scanning Electron Microscope (SEM). Results indicated that the most suitable solgel: chitosan ratio for hybrid formation was 60:40 after considering the surface morphology of the film, leaching, response time and also the intensities of the spectrum. Besides that, the results also show that the pH indicator could be successfully entrapped inside the hybrid film and would still retain its chemical behavior just as in solution. The sensing material was found to have good repeatability when reacted with buffer solution and showed RSD values of 4.24 % and 5.96 % in buffer solution at pH 2.0 and pH 11.0, respectively. The entrapped indicator also showed good photo stability with RSD of 5.35 % for the duration of 8 hours. However; the reproducibility of the hybrid film was quite low with a RSD value of 18.40 % and 31.22 % at wavelength of 500 nm and 600 nm, respectively due to leaching.
    [Penyelidikan ini difokuskan kepada pembangunan dan pengoptimuman bahan hibrid antara sol-gel dan kitosan untuk membentuk suatu matriks baru bagi penyediaan bahan penderia kimia yang dapat mengatasi kekurangan tertentu dalam bahan sol-gel danjuga kitosan. Teknik penyalutan celup telah digunakan untuk penyediaan filem nipis di atas penyokong slaid kaca mikroskop. Untuk tujuan pengoptimuman, timol biru dipilih sebagai penunjuk pH dan dipegunkan di dalam filem. Filem nipis dicirikan menggunakan Spektrofotometer UL-Nampak. Kajian morfologi ke atas permukaan filem pula dilakukan dengan menggunakan Mikroskop Imbasan Elektron (MIE). Keputusan yang diperolehi menunjukkan bahawa nisbah sol-gel:kitosan yang paling sesuai ialah 60:40 dengan mempertimbangkan dari segi morfologi permukaan filem, kelarutresapan, masa rangsangan dan juga keamatan spektrum. Selain itu, keputusan menunjukkan bahawa penunjuk pH berjaya dipegunkan dalam filem hibrid sol-gel-kitosan dan mampu mengekalkan sifat kimianya sebagaimana dalam larutan. Bahan penderia kimia ini didapati mempunyai kebolehulangan yang baik apabila bertindak dengan larutan penimbal dan menunjukkan nilai RSD yang baik iaitu 4.24% dan 5.96% dalam larutan penimbal pH 2.0 dan pH 11.0, masing-masingnya. Penunjuk pH terpegun turut menunjukkan kestabilan foto yang baik (RSD = 5.35%) untuk tempoh 8 jam. Walau bagaimanapun, kebolehasilan filem agak rendah dengan RSD yang bernilai 18.40% dan 31.22 % pada panjang gelombang 550 nm dan 600 nm masing-masing akibat daripada kelarut resapan].
  12. Penggunaan jaringan neural tiruan untuk analisis kuantitatif ion Al (III) berasaskan pengecaman corak spektrum serapan
    Tan LL, Musa Ahmad
    Sains Malaysiana, 2008;37.
    Analisis kuantitatif telah dilakukan untuk menentukan kepekatan ion aluminium (Al3+) dalam larutan dengan menggunakan kaedah spektrofotometri UL-Nampak dan jaringan neural tiruan (ANN). Reagen morin telah digunakan untuk membentuk kompleks morin-Al(III). Pencirian terhadap reagen dalam larutan termasuk analisis kestabilan foto reagen, kesan pH, kesan kepekatan, masa rangsangan, julat kepekatan dinamik dan kebolehulangan telah dilakukan. Penggunaan ANN telah berupaya memanjangkan julat kepekatan dinamik ion Al3+ sehingga julat kepekatan 1-13 ppm.
  13. Penggunaan Jaringan Neural Tiruan bagi menentukan Kekeruhan air berdasarkan Pencaman Corak Spektrum Pantulan (The use of Artificial Neural Network for Determination of Water Turbidity based on Pattern Recognition of the Reflectance Spectrum)
    Mohd. Azwani Shah Mat Lazim, Musa Ahmad, Zuriati Zakaria, Mohd. Nasir Taib
    Sains Malaysiana, 2005;34.
    Artificial neural network (ANN) was used in this study to determine water turbidity by using back propagation algorithm. Three wavelengths which represent reflectance intensity for eight standard samples were used as training input. The finding from the study shows that the trained network with number of epochs of 250,000 and learning rate of 0.001 gave the lowest sum of squared error (SSE) of 0.04. ANN was able to predict the turbidity of water based on the pattern recognition of the reflectance spectrum. The architecture of optimized ANN used in this study was 3:25:1. The average prediction error was 0.02.
    [Jaringan neural tiruan (ANN) dengan lagoritma perambatan balik (BP) telah digunakan dalam kajian ini untuk menentukan kekeruhan air. Tiga panjang gelombang yang mewakili serapan bagi lapan sampel telah dipilih sebagai imput latihan. Hasil kajian menunjukkan bagi jaringan terlatih dengan bilangan ulangan latihan 250,000 dan kadar pembelajaran 0.001 telah memberikan nilai SSE yang terendah iaitu 0.04. Dalam kajian ini jaringan ANN didapati boleh menentu dan meramalkan nilai kekeruhan sample air berdasarkan corak serapan pantulan. Arkitektur yang sesuai bagi kajian ini adalah 3:25:1. Purata ralat ramalan adalah 0.02].
  14. Pembangunan sensor optik pH berasaskan reagen kurkumin terpegun dalam matriks hibrid sol-gel/kitosan melamin
    Rosmawani Mohammad, Musa Ahmad, Jamaluddin Mohd Daud
    Sains Malaysiana, 2009;38.
    Sensor optik pH berasaskan reagen kurkumin terpegun dalam matriks hibrid sol-gel/kitosan melamin telah dibangunkan dalam kajian ini. Sensor optik pH ini memberikan rangsangan linear pada julat pH 9-13 (R2 = 0.9846). Seterusnya, nilai RSD kebolehulangan adalah 7.38% - 9.65%, manakala nilai RSD kebolehasilan pula adalah 2.18% - 4.72%. Kestabilanfoto yang baik bagi reagen kurkumin terpegun diperolehi apabila filem disimpan dalam persekitaran gelap dengan nilai RSD 3.69% untuk tempoh kajian 3 minggu. Tiada kesan histerisis diperhatikan apabila sensor digunakan untuk mengukur pH dalam kitaran pH 2-12-2. Masa rangsangan sensor adalah 10-20 saat. Penentuan nilai pH bagi beberapa sampel sebenar menggunakan sensor pH yang dihasilkan dalam kajian ini menunjukkan tiada perbezaan secara signifikan pada nilai pH yang diperolehi apabila dibandingkan dengan keputusan yang diperolehi menggunakan meter pH.
  15. Molecularly imprinted polymer for recognition of p-Xylene in organic medium
    Norlaili Abu Bakar, Musa Ahmad, Rusli Daik
    Sains Malaysiana, 2008;37:233-237.
    Molecularly imprinted polymer (MIP) based on acrylate monomer was prepared at 80°C for 5 hours using p-xylene and ethylene glycol dimethacrylate (EGDMA) as a template and crosslinking agent respectively. The polymer obtained was washed with a mixture of acetic acid and methanol (1:4) and dried in the vacuum oven at 80°C. FTIR spectrum showed that all the templates were leached out from polymer during excessive washing and drying stage. The rebinding test result showed that the MIP was bonded with the analyte in the presence of organic solvents as shown by FTIR spectroscopy. The SEM micrograph showed that non-imprinted polymer (NIP) had no cavity as compared to MIP.
  16. Kesan penambahan surfaktan tak-ionik kepada kompleks Al(III)-morin dalam penentuan aluminium (III) akues secara spektrofotometri
    Faiz Bukhari Mohd Suah, Musa Ahmad, Lee YH
    Sains Malaysiana, 2016;45:1807-1814.
    Dalam kajian ini, kesan surfaktan tak-ionik terhadap kompleks Al(III)-morin telah dijalankan. Surfaktan tak-ionik didapati telah meningkatkan bacaan serapan kompleks Al(III)-morin. Penambahan triton X-100 kepada kompleks Al(III)-morin telah membolehkan penentuan ion Al(III) dalam kuantiti submikrogram pada pH4.00 dijalankan. Bacaan serapan maksimum adalah pada 425 nm dengan serapan molar, ε, 9.31 × 103 l.mol-1cm-1. Graf kalibrasi bagi penentuan ion Al(III) adalah linear daripada 0.03 hingga 2.0 μg mL-1 dengan had pengesanan 0.015 μg mL-1 telah diperoleh dalam kajian ini. Sisihan ralat relatif (r.s.d) ialah 2.2% bagi kepekatan Al(III) 1.0 μg mL-1. Kesan penambahan ion lain terhadap kompleks Al(III)-morin turut dijalankan dan didapati ion Cu(II), Zn(II) dan Pb(II) memberi gangguan yang lebih berbanding ion-ion lain.
  17. Fulltext Intracranial metastatic neuroblastoma mimicking subdural empyema: an interesting case
    Hairuddin NF, Musa AT, Abdullah MS
    Malaysian Journal of Paediatrics and Child Health, 2016;22(1):66-70.
    MyJurnal
    Neuroblastoma is usually presented with abdominal distension. However, central nervous system manifestations of neuroblastoma are uncommon. In this case report, patient presented with uncommon presentation of neuroblastoma and the diagnostic dilemma.
  18. Factor Structure of the Spiritual Well-Being Scale: Cross-Cultural Comparisons Between Jordanian Arab and Malaysian Muslim University Students in Jordan
    Musa AS
    J Transcult Nurs, 2016 Mar;27(2):117-25.
    PMID: 24867886 DOI: 10.1177/1043659614537305
    This study reported the differences in factor structure of the Spiritual Well-Being Scale (SWBS) among Jordanian Arab and Malaysian Muslim participants and further examined its validity and reliability. A convenience sample of 553 Jordanian Arab and 183 Malaysian Malay Muslim university students was recruited from governmental universities in northern Jordan. The findings of this study revealed that this scale consists of two factors for the Jordanian Arab group, representing the "Religious Well-Being" and the "Existential Well-Being" subscales, and consists of three factors for the Malaysian group, representing the "Affiliation/Meaning and Purpose," "Positive Existential Well-Being/God Caring and Love," and "Alienation/Despair" subscales. In conclusion, the factor structure of the SWBS for both groups in this study was psychometrically sound with evidence of acceptable to good validity and reliability. Furthermore, this study supported the multidimensional nature of the SWBS and the earlier notion that ethnicity shapes responses to this scale.
  19. Extending the range of an optical vanadium(v) sensor based on immobilized fatty hydroxamic acid in poly (methyl methacrylate) using artificial neural network
    Azizul Isha, Nor Azah Yusof, Musa Ahmad, Dedy Suhendra, Wan Md. Zin Wan Yunus, Zulkarnain Zainal
    Pertanika Journal of Science & Technology, 2007;15(2):121-130.
    MyJurnal
    An artificial neural network (ANN) was applied for the determination of V(V) based on immobilized fatty hydroxamic acid (FHA) in poly(methyl methacrylate) (PMMA). Spectra obtained from the V(V)-FHA complex at single wavelengths was used as the input data for the ANN. The V(V)-FHA complex shows a limited linear dynamic range of V(V) concentration of 10 - 100 mg/ L. After training with ANN, the linear dynamic range was extended with low calibration error. A three layer feed forward neural network using backpropagation (BP) algorithm was employed in this study. The input layer consisted of single neurons, 30 neurons in hidden a layer and one output neuron was found appropriate for the multivariate calibration used. The network were trained up to 10000 epochs with 0.003 % learning rate. This reagent also provided a good analytical pedormance with reproducibility characters of the method yielding relative standard deviation (RSD) of 9.29% and 7.09% for V(V) at concentrations of 50 mg/ L and 200 mg/ L, respectively. The limit of detection of the method was 8.4 mg/ L.
  20. Equation modeling of Sembulan river, Sabah, as a case study using backward stepwise multiple linear regression
    Rita Sundari, Musa Ahmad, Lee YH
    Sains Malaysiana, 2006;35:67-73.
    An equation modeling on Sembulan river, Sabah, Malaysia, has been undertaken using a backward stepwise multiple linear regression. A good performance has been obtained using a log transformation on water quality data designated as predictors and dependent variable. The regression model is in accordance with the ANOVA result. The temperature, biochemical oxygen demand (BOD), Echerichia Coli, Pb and nitrate were described as continuous predictors, while the river location (downstream, municipal and upstream) was designated as independent string grouping variable, and the chemical oxygen demand (COD) was set up as the dependent variable. The string grouping variable was converted to its dummy variable, which in turn led to design of a three-equation model with respect to river location. The results show that BOD has a strong effect on COD, while Pb and nitrate show less effect on COD. The temperature gives little negative effect on COD, while other variables such as pH, salinity and Cd are excluded from the river modeling since they induce insignificant effects based on backward criterion probability of F-value ≥ 0.100. Using the general linear model with LSD mode, it is revealed that predictor(s) show a remarkable discriminant effect between upstream and municipal/downstream on the 0.05 level. The most effect came from salinity indicated by the canonical discriminant function based on Wilks’ lambda.
Related Terms
    Try searching for something
Filters
Contact Us

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

External Links