Browse publications by year: 2012

  1. Mohamad Hsnul Bolhassan, Noorlidah Abdullah, Vikineswary Sabartnam, Hattori Tsutomu, Sumaiyah Abdullah, Noraswati Mohd Noor Rashid, et al.
    Sains Malaysiana, 2012;41:155-161.
    Macrofungi of the order Polyporales are among the most important wood decomposers and caused economic losses by decaying the wood in standing trees, logs and in sawn timber. Diversity and distribution of Polyporales in Peninsular Malaysia was investigated by collecting basidiocarps from trunks, branches, exposed roots and soil from six states (Johor, Kedah, Kelantan, Negeri Sembilan, Pahang and Selangor) in Peninsular Malaysia and Federal Territory Kuala Lumpur. This study showed that the diversity of Polyporales were less diverse than previously reported. The study identified 60 species from five families; Fomitopsidaceae, Ganodermataceae, Meruliaceae, Meripilaceae, and Polyporaceae. The common species of Polyporales collected were Fomitopsis feei, Amauroderma subrugosum, Ganoderma australe, Earliella scabrosa, Lentinus squarrosulus, Microporus xanthopus, Pycnoporus sanguineus and Trametes menziesii.
    MeSH terms: Malaysia; Polyporaceae; Soil; Trees; Wood; Polyporales; Lentinula; Ganoderma; Fruiting Bodies, Fungal; Coriolaceae; Trametes; Pycnoporus
  2. Yong JW, Xue PS, Zhang CZ
    Sains Malaysiana, 2012;41:149-154.
    Many plants can reproduce both clonally and sexually, and the relative importance between the two modes of reproduction varied among habitats. Clonal diversity and genetic differentiation of the rhizomatous herb, Iris japonica populations, was analyzed by 12 randomly amplified polymorphic DNA markers to determine the extent that reproductive mode varied locally between two habitats, open area of forest edge (OAFE, 2 populations OAFE 1 and OAFE 2) and bamboo forest (BF, 2 populations BF 1 and BF 2) on Jinyun Mountain, southwest China. Total clonal diversity and genetic diversity of I. japonica populations were high. The clonal diversity and genetic diversity of I. japonica populations in BF habitats were lower than those in OAFE habitats. Neighbor-joining tree by Jaccard’s genetic distance showed two genetically distinct groups: OAFE group and BF group. AMOVA indicated that about half of the total variation existed within the four populations, and that genetic differentiation among habitats (BF populations and OAFE populations) was also significant. OAFE habitats were helpful in maintaining clonal diversity and genetic diversity of I. japonica populations than BF habitats. Habitat differences might have distinguished effects on the relative significance of clonal propagation and sexual reproduction, and further have a fatal influence on clonal diversity, genetic diversity and genetic differentiation of I. japonica populations in Jinyun Mountain, southwest China.
  3. Yarmohammadi M, Mostafaei H, Safaei M
    Sains Malaysiana, 2012;41:371-377.
    In this research, the Markov switching autoregressive (MS-AR) model and six different time series modeling approaches are considered. These models are compared according to their performance for capturing the Iranian exchange rate series. The series has dramatic jump in early 2002 which coincides with the change in policy of the exchange rate regime. Our criteria are based on the AIC and BIC values. The results indicate that the MS-AR model can be considered as useful model, with the best fit, to evaluate the behaviors of Iran’s exchange rate.
  4. Zerafat Angiz Langroudi M, Adli Mustafa, Norain Abdul Ghani, Anton Abdulbasah Kamil
    Sains Malaysiana, 2012;41:361-366.
    The Analytic Hierarchy Process (AHP) is a recognised modern approach to solve decision making problems. Initially introduced by Saaty in 1971 as a tool for handling individual decision making situation, the method has since been extended to incorporate groups. In this paper, a new method for AHP group decision making is proposed. The method integrates AHP with a Data Envelopment Analysis (DEA)-based preferential aggregation method. It manipulates the preferential weights and ranking aspect of each decision maker in coming up with an optimisation model that determines the best efficiency score of each alternatives. These efficiency scores are then used to rank the alternatives and determine the group decision weights. A comparative analysis of the method with another AHP group decision making method indicates a similar ‘satisfactory index’ level.
  5. Ibrahim N, Yusrianto E, Zalita Z, Ibrahim Z
    Sains Malaysiana, 2012;41:339-344.
    Ba0.6Sr0.4TiO3 (BST) thin films were prepared on TiO2 buffer layers. The buffer layers were prepared using sol-gel method, followed by annealing process at different temperature from 300 to 550 oC with 50 oC interval for 30 min in air. The microstructure and electrical properties of BST were then investigated. Increasing the annealing temperature increased. The buffer layer thickness BST films prepared on thicker buffer layer showed improved crystallinity. Without the buffer
    layer, BST crystallization cannot occur at 700 oC. However with buffer layer, 700 oC is sufficient for the process to occur. The BST grain size increased with the buffer grains increment. The existence of TiO2 buffer layer increased the current density. The dielectric constant, εr´ and dielectric loss were not affected much by the buffer layer except at frequency around 1 kHz that showed an increment in the εr’ value with the increment of the annealing temperature.
  6. Mosadeghzad Z, Zuriati Zakaria, Asmat A, Gires U, Wickneswari R, Pittayakhajonwut P, et al.
    Sains Malaysiana, 2012;41:333-337.
    Marine fungus Fusarium proliferatum derived from marine sponge collected along Pulau Tinggi, Malaysia was cultivated on Potato Dextrose Broth and incubated for 7 days at 30oC. The liquid cultures were then extracted using ethyl acetate. The crude extract was investigated for its anti-microbial activity and was passed through Sephadex column and the fractions were collected. Reverse phase HPLC was used to monitor the component of crude extract. HPLC guided purification of crude extract resulted in the isolation of linoleic acid, 4-hydroxy phenethyl alcohol, 2,5-furandimethanol and adenosine. Their structures were elucidated by spectroscopic methods.
    MeSH terms: Acetates; Adenosine; Animals; Chromatography, High Pressure Liquid; Fungi; Fusarium; Glucose; Malaysia; Phenylethyl Alcohol; Porifera; Solanum tuberosum; Spectrum Analysis; Linoleic Acid; Complex Mixtures
  7. Tan ES, Aminah Abdullah, Khalid Hamid Musa, Mohammad Yusof Maskat, Maaruf Abd Ghani
    Sains Malaysiana, 2012;41:319-324.
    The effect of solvent type in antioxidant compounds extraction from banana tissues was studied. The solvent system used was pure methanol, ethanol, acetone and their aqueous solution at 50% and 70% concentrations. Comparison among three common cultivars of banana in Malaysia (Berangan, Mas and Raja) had been done and their antioxidant activities were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging system, ferric reducing ability in plasma (FRAP)
    assays and total phenolic content (TPC) assays. Acetone 70% had the strongest antioxidant compounds extraction power as compared to other solvent. All banana samples were found to be low in primary antioxidant but powerful secondary antioxidant source of fruit. The ascending order of banana cultivars in term of their antioxidant activities in all antioxidant assays carried out were Berangan < Mas < Raja. FRAP-TPC assays were highly correlated (R2>0.70) than FRAP-DPPH
    and TPC-DPPH assays due to the same mechanism that occurred in the reaction of FRAP and TPC assays.
    MeSH terms: Acetone; Ethanol; Methanol; Animals; Antioxidants; Biphenyl Compounds; Fruit; Malaysia; Phenols; Picrates; Skates (Fish); Solvents; Musa
  8. Zulfahimi A, Wan Zuhairi W, Raihan M, Sahibin A, Wan Mohd Razi I, Tukimat L, et al.
    Sains Malaysiana, 2012;41:303-312.
    Amang or tin tailing is commonly found in the vicinity of disused mining area and responsible in downgrading the water quality, landscape and mechanical behaviour of soils. It was generated from extraction process of separating valuable metal from particular ore. This paper presents the geotechnical characteristics of amang-contaminated clay soil. The geotechnical properties of uncontaminated soils were studied in order to compare to that of amangcontaminated soils. The base soil used in this study represents completely weathered horizon of metasedimentary rock. Meanwhile, tin tailing sample was taken from the disused mine at Sungai Lembing, Pahang. The geotechnical characterisations of base soil and contaminated soils were determined based on consistency index, compaction behaviour, hydraulic conductivity and undrained shear strength (UU tests). Contaminated soil samples were prepared by adding 5, 10 and 20% of tailing, based on dry weigh of the studied base soil. The results from the particle size distribution analysis showed that residual soil from metasedimentary rock comprised 42.6% clay, 32.2% silt and 25.2% sand whilst tailing was dominated by 98% of sand fraction. XRD analysis indicated the presence of quartz, kaolinite and muscovite minerals in the studied soil. The specific gravity of soil used is 2.67 and the pH is 3.88. Tailing found to have higher specific gravity of 3.37. The consistency index of contaminated soils showed that liquid limit, wL and plastic limit, wP decreased with the increase in the percentage of tailing added to the soil samples. The value of maximum dry density, dry max increased while optimum moisture content decreased due to the increase in tailing content in soil sample. The permeability of contaminated soil also increased with the increase in tailing
    contents ranged from 19.8 cm/hr to 23.8 cm/hr. The undrained shear strength, Cu, of contaminated soil decreased from 646 kPa (5% of tailing) to 312 kPa (20% of tailing) suggesting that the presence of tailing has influenced the geotechnical properties on the studied soil.
  9. Parris B, Jaman R, Latiff A
    Sains Malaysiana, 2012;41:299-301.
    A new species of fern, Oreogrammitis translucens, is described and illustrated from Maliau Basin Conservation Area, Sabah, Malaysia.
    MeSH terms: Malaysia; Polypodiaceae; Ferns
  10. Muhammad Ibrahim, Kyung HH, Sang KH, Young SZ, Seung OH
    Sains Malaysiana, 2012;41:285-291.
    Anthropogenically disturbed soils have unique properties. In most of the ecosystems, especially under disturbed soil conditions, the soil properties are controlled by the accumulated materials. However, the equilibrium between the already present soil mass and the accumulated soil mass is very fragile and is affected by many factors. There are diversity of views about their identification and interpretations. This paper reports on the physico-chemical properties of the investigated
    sites under different texture soil accumulate. Three sites namely Chung-nam university field (Site-I), Chung-buk Geosan (Site-II) and Yong-in (Site-III) were investigated for diversity in physico-chemical properties. In situ and ex situ physical and chemical properties were determined and comparisons were made for soil profiles examined at three sites. The classification of disturbed soils largely depends upon the system followed for classification. The objectives of this paper
    were to compare the properties of the disturbed soils and to classify for further research investigations of such soils. Abrupt change in electrical conductivity at Site-III was recorded ranged between 10.7 dS m–1 and 1.1 dS m–1 below 20 cm depth. Sudden and abrupt changes in infiltration rates at all sites were also calculated. The data suggested that the soil texture of the accumulated soil had also affected the properties of the underlying soil. Apparently, the difference in the properties seems to be the result of overlying soil accumulates with different texture. The disturbed soils need to be studied in detail and groupings be made on the basis of genesis and similarities.
  11. MD Yeamin Hossain, MD Abu Sayed Jewel, Fulanda B, Ferdous Ahamed, Sharmeen Rahman, Saleha Jasmine, et al.
    Sains Malaysiana, 2012;41:277-284.
    The seasonal abundance, dynamics and composition of the filamentous Cyanobacteria Planktothrix spp. was studied over a 1-year period in two storm-water-fed earthen fishponds in Rajshahi city, northwestern Bangladesh. Sampling was conducted monthly using plankton net (25 μm mesh size) and the samples preserved in 5% formalin. Water quality parameters including water temperature, transparency, pH, dissolved oxygen (DO), biological oxygen demand (BOD),
    free carbon dioxide (CO2), nitrite-nitrogen (NO2-N), nitrate-nitrogen (NO3-N), ammonium (NH4
    +), oxidation reduction index (rH2) were recorded during each sampling. Two species; Planktothrix agardhii and Planktothrix rubescens were identified during the study with P. agardhii recording higher abundance (p<0.05) all year round. The Planktothrix cell density was highest during March: 3.06×106 cells/L and 1.23×106 cells/L in Pond-1 and 2, respectively. The abundance of P. agardhii was relatively higher in spring. The cell densities increased with increasing temperature, pH, and nutrient concentration. Lower cell densities were recorded during periods of high BOD. The results of this study provide a useful guide for aquaculturists and other environmental scientists for the management of the cyanotoxin producing algal blooms of Planktothrix spp. in fertilized fish ponds and other aquatic habitats.
  12. Tham L, Roslindar Nazar
    Sains Malaysiana, 2012;41:1643-1649.
    A steady laminar mixed convection boundary layer flow about an isothermal solid sphere embedded in a porous medium filled with a nanofluid has been studied for both cases of assisting and opposing flows. The transformed boundary layer equations were solved numerically using an implicit finite-difference scheme. Three different types of nanoparticles, namely Cu, Al2O3 and TiO2 in water-based fluid were considered. Numerical solutions were obtained for the skin friction coefficient, the velocity and temperature profiles. The features of the flow and heat transfer characteristics for various values of the nanoparticle volume fraction and the mixed convection parameters were analyzed and discussed.
    MeSH terms: Aluminum Oxide; Hot Temperature; Temperature; Porosity; Friction; Convection; Nanoparticles; Physical Phenomena
  13. Wan Rosli W, Nurhanan A, Aishah M
    Sains Malaysiana, 2012;41:1565-1570.
    Nutrient composition and sensory investigation of butter biscuits incorporated with various levels of grey oyster mushroom (Pleurotus sajor-caju, PSC) powder were studied. The biscuits were formulated with either 0, 2, 4 or 6% of PSC powder to partially replacing wheat flour. Results showed butter biscuit formulated with 6% PSC powder significantly (p≤ 0.05) recorded the highest protein content (6.94%) as compared to control (6.50%). Meanwhile, the addition of 2% PSC powder in biscuit does not affect the fat content (20.71%) compared to control (20.52%). Both biscuit containing 4% and 6% PSC powder recorded 5.34 g/ 100 g and 5.52 g/ 100 g total dietary fibre (TDF), respectively and significantly higher (p≤0.05) than control biscuit (4.84 g/ 100 g). Biscuits formulated with 4% and 6% PSC powder had significantly higher β-glucan concentration at 0.72 and 0.79 g/ 100 g than control biscuit (0.66 g/ 100 g). In the sensory evaluation, biscuits incorporated with 2% PSC powder had the highest scores for all sensory attributes except for crispiness and flavor. Butter biscuit containing 4% PSC powder had score values of 5.5 and 4.5 for crispiness and flavor, respectively. The present study suggested that incorporation of PSC powder up to 4% to replace wheat flour improved crispiness and flavour, increased concentration of protein, dietary fibre and β-glucan but did not affect the fat content of butter biscuit.
  14. Ghanthimathi S, Aminah Abdullah, Salmijah S, Ujang T, Nurul Izzah A
    Sains Malaysiana, 2012;41:1557-1564.
    Fish is one of the most important sources of arsenic exposure in human diet and the Food Safety and Quality Division, Ministry of Health since 2007 has required routine monitoring of total arsenic in seafoods such as fish. This study describes an improved extraction method of total arsenic in fish using microwave assisted acid digestion procedure before being analysed by inductively coupled plasma mass spectrometry (ICP-MS). The parameters studied were pre-treatment of sample, digestion temperature, time programme and the chemicals (HNO3/H2O2) used. Arsenic contents in fish samples under these conditions were compared using the standards additions technique. Microwave assisted acid digestion method with a combination of ultrapure concentrated nitric acid (HNO3) to concentrated hydrogen peroxide (H2O2) at a ratio of 7 mL: 1 mL, run time of 25 min and digestion temperature of 200°C with no pre-treatment was found to have recovery of 100.7% as compared to other digestion procedure where the recovery were 115.5, 111.6 and 101.8%. Validation using certified reference material (CRM) of fish tissue (DORM-3) showed a recovery of 101.4 ± 2.5% for total arsenic from the CRM.
  15. Mahanem Matnoor, Nani Rahayu Mohd. Radzuan
    Sains Malaysiana, 2012;41:1549-1556.
    Gynura procumbens (GP) adalah sejenis tumbuhan herba yang digunakan bagi merawat pelbagai jenis penyakit seperti rheumatoid, darah tinggi, masalah ginjal dan juga diabetes. Diabetes Mellitus (DM) adalah sejenis penyakit kronik dan salah satu komplikasi penyakit ini ialah masalah kesuburan dan libido. Kajian ini dijalankan untuk mengenal pasti potensi ekstrak GP dalam mengatasi masalah kesuburan dalam kalangan pesakit diabetes. Ekstrak metanol GP dengan fraksi etil asetat digunakan dalam kajian ini. Aruhan diabetes dilakukan dengan suntikan dadah Streptozotosin sebanyak 55 mg/kg berat tikus secara intravena. Empat kumpulan tikus teraruh diabetes dirawat dengan 50 mg/kg GP (n=12), 300 mg/kg GP (n=12) dan 300 mg/kg metformin (n=12). Kumpulan ke-empat adalah kumpulan diabetik tanpa sebarang rawatan dan dijadikan kawalan negatif (n=12) dan satu kumpulan tikus normal yang diberi air suling dijadikan kawalan normal (n=12). Satu minggu selepas rawatan, enam ekor tikus daripada setiap kumpulan diuji kelakuan seksual sebelum dikorbankan untuk kajian kesuburan. Ujian yang sama dilakukan ke atas baki haiwan dalam setiap kumpulan pada minggu kedua rawatan. Pada semua dos rawatan, ekstrak GP menunjukkan kesan anti-hiperglisemia sebagaimana kumpulan metformin. Rawatan dengan dos rendah GP (50 mg/kg) selama dua minggu mencatatkan bilangan sperma yang paling tinggi iaitu sebanyak (35.52 ± 6.54) × 106 sperma berbanding kawalan diabetik, (23.72 ± 5.12) × 106 sperma. Kumpulan ini turut mencatatkan peratus jumlah pergerakan sperma gred a (paling progresif) yang tinggi iaitu sebanyak 38.41% berbanding 12.79% bagi kumpulan kawalan diabetik. Tikus yang dirawat dengan GP turut menunjukkan peningkatan kesan libido dengan tempoh pendam pemanjatan dikurangkan dan bilangan pemanjatan meningkat berbanding tikus kawalan diabetik. Kajian ini menunjukkan ekstrak metanol GP dengan fraksi etil asetat ini mampu meningkatkan kesuburan dan libido tikus diabetik pada dos yang rendah (50 mg/kg) serta dalam tempoh yang singkat.
  16. Latiff A
    Sains Malaysiana, 2012;41:1503-1508.
    Morphological description of seeds of Parthenocissus and Ampelopsis is given and followed by a discussion of its taxonomic significance.
    MeSH terms: Seeds; Vitaceae; Ampelopsis
  17. Jashim Uddin M, Pop I, Md. Ismail A
    Sains Malaysiana, 2012;41:1475-1482.
    Two dimensional steady laminar boundary layer flow of a nanofluid over a convectively heated vertical flat plate with linear momentum slip boundary condition has been studied numerically. The governing boundary layer equations are non-dimensionalized and transformed into a two point boundary value problem of coupled nonlinear ordinary differential equations in similarity variable before being solved numerically. The resulting equations with corresponding boundary conditions have been solved numerically by Maple 13 which uses Runge-Kutta-Fehlberg fourth- fifth order numerical algorithm for solving nonlinear ordinary boundary value problems. Our analysis reveals that the similarity solution is possible if the convective heat transfer coefficient is directly proportional to x–1/4, where x is the axial distance from the leading edge of the plate. Solutions depend on the seven parameters: Prandtl number, buoyancy ratio, Brownian motion, thermophoresis, Lewis number, momentum slip and convective heat transfer. The effects of the governing parameters on the flow and heat transfer characteristics have been shown graphically and discussed. Comparisons of the present numerical solution with the existing results in the literature are made and our results are in very good agreement. Results for the skin friction factor, the reduced Nusselt and the Sherwood numbers are provided in tabular form for various values of the convective heat transfer parameter. It is found that the skin friction coefficint reduces with the momentum slip and the buoyancy ratio parameters whilst it enhances with the convective heat transfer parameter. It is also found that mass transfer rate enhances with the Lewis number and the convective heat transfer parameter whilst it falls with the thermophoresis parameter.
  18. Shahriza S, Ibrahim J, Shahrul Anuar M
    Sains Malaysiana, 2012;41:1431-1435.
    The breeding activities of the Dwarf Toad, Ingerophrynus parvus were observed under natural conditions at Sungai Junjong, Kulim, Kedah, Peninsular Malaysia for a period of 12 months. Breeding parameters, such as calling activities, amplecant pairs, eggs deposition and presence of tadpoles were examined every week in each month. Pearson correlation was used to analyse the relationship between rainfall and each breeding parameter. The results showed positive relationships between rainfall and calling activities (r=0.74), between rainfall and amplexus activities (r=0.52), and between rainfall and spawning activities (0.81).
    MeSH terms: Animals; Breeding; Bufonidae; Eggs; Larva; Malaysia; Physiological Phenomena
  19. Lee TT, Kamisah Osman
    Sains Malaysiana, 2012;41:1301-1307.
    Tajuk Elektrokimia didapati sukar dipelajari kerana konsep abstrak yang melibatkan tahap perwakilan makroskopik, mikroskopik dan simbolik. Kajian lepas menunjukkan bahawa animasi dan simulasi menggunakan teknologi maklumat dan komunikasi (TMK) boleh membantu pelajar membayangkan dan seterusnya memperkuatkan pemahaman mereka dalam mempelajari tajuk kimia yang abstrak. Ekoran daripada itu, modul multimedia interaktif dengan agen pedagogi (MMIAP) yang dinamakan Makmal EK (Elektrokimia) dibangunkan dalam usaha membantu pelajar dalam mempelajari Elektrokimia. Reka bentuk penyiasatan kuasi eksperimen dengan ujian pra/pos kumpulan kawalan tidak setara dijalankan dalam usaha untuk menilai keberkesanan MMIAP Makmal EK terhadap pemahaman konsep pelajar dalam mempelajari elektrokimia. Seramai 127 orang pelajar tingkatan empat dari dua buah sekolah menengah terlibat dalam kajian ini. Setiap sekolah mempunyai sebuah kumpulan rawatan dan sebuah kumpulan kawalan yang diajar oleh guru kimia yang sama. Ujian pencapaian pra dan pos diberikan untuk menilai pemahaman konsep Elektrokimia pelajar sebelum dan selepas mempelajari kimia. Hasil kajian menunjukkan bahawa intervensi seperti yang direkabentuk dalam kajian menghasilkan perbezaan yang bererti antara kumpulan kawalan dan kumpulan rawatan dalam memahami konsep Elekotrokimia.
    MeSH terms: Animals; Autonomic Nervous System Diseases; Thoracica; Diabetic Neuropathies; Fenofibrate; Multimedia
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