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  1. Fabrication and performance evaluation of blood compatible hemodialysis membrane using carboxylic multiwall carbon nanotubes and low molecular weight polyvinylpyrrolidone based nanocomposites
    Irfan M, Irfan M, Idris A, Baig N, Saleh TA, Nasiri R, et al.
    J Biomed Mater Res A, 2019 03;107(3):513-525.
    PMID: 30484939 DOI: 10.1002/jbm.a.36566
    This study focused to optimize the performance of polyethersulfone (PES) hemodialysis (HD) membrane using carboxylic functionalized multiwall carbon nanotubes (c-MWCNT) and lower molecular weight grade of polyvinylpyrrolidone (PVP-k30). Initially, MWCNT were chemically functionalized by acid treatment and nanocomposites (NCs) of PVP-k30 and c-MWCNT were formed and subsequently blended with PES polymer. The spectra of FTIR of the HD membranes revealed that NCs has strong hydrogen bonding and their addition to PES polymer improved the capillary system of membranes as confirmed by Field Emission Scanning Electron Microscope (FESEM) and leaching of the additive decreased to 2% and hydrophilicity improved to 22%. The pore size and porosity of NCs were also enhanced and rejection rate was achieved in the establish dialysis range (<60 kDa). The antifouling studies had shown that NCs membrane exhibited 30% less adhesion of protein with 80% flux recovery ratio. The blood compatibility assessment disclosed that NCs based membranes showed prolonged thrombin and prothrombin clotting times, lessened production of fibrinogen cluster, and greatly suppressed adhesion of blood plasma than a pristine PES membrane. The results also unveiled that PVP-k30/NCs improved the surface properties of the membrane and the urea and creatinine removal increased to 72% and 75% than pure PES membranes. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 513-525, 2019.
  2. Fulltext Genotype Diversity of Newcastle Disease Virus in Nigeria: Disease Control Challenges and Future Outlook
    Bello MB, Yusoff KM, Ideris A, Hair-Bejo M, Peeters BPH, Jibril AH, et al.
    Adv Virol, 2018;2018:6097291.
    PMID: 30631359 DOI: 10.1155/2018/6097291
    Newcastle disease (ND) is one of the most important avian diseases with considerable threat to the productivity of poultry all over the world. The disease is associated with severe respiratory, gastrointestinal, and neurological lesions in chicken leading to high mortality and several other production related losses. The aetiology of the disease is an avian paramyxovirus type-1 or Newcastle disease virus (NDV), whose isolates are serologically grouped into a single serotype but genetically classified into a total of 19 genotypes, owing to the continuous emergence and evolution of the virus. In Nigeria, molecular characterization of NDV is generally very scanty and majorly focuses on the amplification of the partial F gene for genotype assignment. However, with the introduction of the most objective NDV genotyping criteria which utilize complete fusion protein coding sequences in phylogenetic taxonomy, the enormous genetic diversity of the virus in Nigeria became very conspicuous. In this review, we examine the current ecological distribution of various NDV genotypes in Nigeria based on the available complete fusion protein nucleotide sequences (1662 bp) in the NCBI database. We then discuss the challenges of ND control as a result of the wide genetic distance between the currently circulating NDV isolates and the commonest vaccines used to combat the disease in the country. Finally, we suggest future directions in the war against the economically devastating ND in Nigeria.
  3. Developing functionally graded PVA hydrogel using simple freeze-thaw method for artificial glenoid labrum
    Wahab AHA, Saad APM, Harun MN, Syahrom A, Ramlee MH, Sulong MA, et al.
    J Mech Behav Biomed Mater, 2019 03;91:406-415.
    PMID: 30684888 DOI: 10.1016/j.jmbbm.2018.12.033
    Intact glenoid labrum is one of passive stabilizer for glenohumeral joint, which have various stiffness at different region. The aim of this study is to develop new artificial glenoid labrum from Polyvinyl Alcohol (PVA) hydrogel, which known as good biomaterial due to its biocompatibility and ability to tailor its modulus. PVA hydrogel was formed using freeze-thaw (FT) method and the stiffness of PVA was controlled by manipulating the concentration of PVA and number of FT cycles. Then, the gradual stiffness was formed using simple diffusion method by introducing the pre-freeze-and-thaw steps. The results showed 20% PVA with three FT cycles suit to highest stiffness of glenoid labrum while 10% PVA with three FT cycles suit to lowest stiffness of glenoid labrum. The functionally graded PVA hydrogel was then developed using the same method by diffusing two mixture (20% PVA and 10% PVA). Mechanical compression test showed, the highest modulus (0.41 MPa) found at the 20% PVA region and lowest modulus (0.1 MPa) found at 10% PVA region. While, at intermediate region, the compressive modulus was in between 20% and 10%, 0.2 MPa. The existence of gradual stiffness was further prove by checking crystallinity of material at each region using Differential Scanning Calorimetry (DSC) and Wide Angle X-ray Diffraction (WAXD). Microstructure of material was obtained from Scanning Electron Microscopy (SEM). This functionally graded PVA hydrogel also able to reduce about 51% of stress at glenoid implant and up to 17% for micromotion at the interfaces. Existence of artificial glenoid labrum could minimize the occurrence of glenoid component loosening.
  4. Fulltext In-hospital mortality of cardiogenic shock complicating ST-elevation myocardial infarction in Malaysia: a retrospective analysis of the Malaysian National Cardiovascular Database (NCVD) registry
    Venkatason P, Zubairi YZ, Wan Ahmad WA, Hafidz MI, Ismail MD, Hadi MF, et al.
    BMJ Open, 2019 05 05;9(5):e025734.
    PMID: 31061031 DOI: 10.1136/bmjopen-2018-025734
    OBJECTIVES: Cardiogenic shock (CS) complicating ST-elevation myocardial infarction (STEMI) carries an extremely high mortality. The clinical pattern of this life threatening complication has never been described in Malaysian setting. This study is to investigate the incidence, clinical characteristics and outcome of STEMI patients with CS in our population.

    DESIGN: A retrospective analysis of STEMI patients from 18 hospitals across Malaysia contributing to the Malaysian National Cardiovascular Database-acute coronary syndrome) registry (NCVD-ACS) year 2006-2013.

    PARTICIPANTS: 16 517 patients diagnosed of STEMI from 18 hospitals in Malaysia from the year 2006 to 2013.

    PRIMARY OUTCOME MEASURES: In-hospital and 30 day post-discharge mortality.

    RESULTS: CS complicates 10.6% of all STEMIs in this study. They had unfavourable premorbid conditions and poor outcomes. The in-hospital mortality rate was 34.1% which translates into a 7.14 times mortality risk increment compared with STEMI without CS. Intravenous thrombolysis remained as the main urgent reperfusion modality. Percutaneous coronary interventions (PCI) in CS conferred a 40% risk reduction over non-invasive therapy but were only done in 33.6% of cases. Age over 65, diabetes mellitus, hypertension, chronic lung and kidney disease conferred higher risk of mortality.

    CONCLUSION: Mortality rates of CS complicating STEMI in Malaysia are high. In-hospital PCI confers a 40% mortality risk reduction but the rate of PCI among our patients with CS complicating STEMI is still low. Efforts are being made to increase access to invasive therapy for these patients.

  5. Sel Stem dalam Perkembangan Darah(Stem Cell in Blood Development)
    Shahrul Hisham Zainal Ariffin, Intan Zarina Zainal Abidin, Sahidan Senafi, Nor Muhammad Mahadi, Rohaya Megat Abdul Wahab, Zaidah Zainal Ariffin
    Sains Malaysiana, 2005;34.
    Stem cells, also known as mother cells are capable of undergoing both cell division and differentiation. The most primitive stem cells are totipotent cells which are capable of producing a complete organism from one cell. There are two types of haemopoietic stem cells depending on their developmental stages known as embryo and adult haemopoietic stem cells. Studies showed that only 0.01-0.05% of total bone marrow cell population consists of haemopoietic stem cells. This small population of stem cells exists in three different sizes with different characteristics. In addition, the microenvironment which contains various regulatory molecules plays an important role in the differentiation of stem cells into specific adult cells.
    [Sel stem juga dikenali sebagai sel induk berupaya untuk menjalani kedua-dua proses pembahagian dan pembezaan sel. Sel stem yang paling primitif iaitu sel totipoten berupaya untuk membentuk satu organisma lengkap daripada satu sel. Sel stem hemopoietik terdiri daripada dua jenis bergantung kepada peringkat perkembangan individu iaitu sel stem hemopoietik embrio dan dewasa. Kajian mendapati hanya 0.01-0.05% daripada keseluruhan populasi sel sumsum tulang berupaya bertindak sebagai sel stem hemopoietik. Daripada julat yang kecil ini sel stem hemopoietik wujud dalam tiga saiz yang mempunyai ciri yang berbeza. Selain daripada itu mikrosekitaran yang mempunyai molekul-molekul regulatori yang berbeza-beza juga memainkan peranan yang penting dalam pembezaan sel stem kepada sel-sel matang yang spesifik].
  6. Effect of ZnO addition on structural properties of ZnO-PANi/carbon black thin films
    Siti Fariza Mat Tahir, Mohammad Hafizuddin Haji Jumali, Norhashimah Ramli, Izura Izzuddin, Muhammad Yahaya, Muhamad Mat Salleh, et al.
    Sains Malaysiana, 2012;41:1001-1004.
    The aim of this project was to investigate the effect of ZnO addition on the structural properties of ZnO-PANi/carbon black thin films. The sol gel method was employed for the preparation of ZnO sol. The sol was dried for 24 h at 100°C and then annealed at 600°C for 5 h. XRD characterization of the ZnO powder showed the formation of wurtzite type ZnO
    crystals. The ZnO powder were mixed into PANi/carbon black solution which was dissolved into M-Pyrol, N-Methyl-2-Pyrrolidinone (NMP) to produce a composite solution of ZnO-PANi/carbon black. The weight ratio of ZnO were 4 wt%, 6 wt% and 8 wt%. The composite solutions were deposited onto glass substrates using a spin-coating technique to fabricate
    ZnO-PANi/carbon black thin films. AFM characterization showed the decreasing of average roughness from 7.98 nm to 2.23 nm with the increment of ZnO addition in PANi/carbon black films. The thickness of the films also decreased from 59.5 nm to 28.3 nm. FESEM image revealed that ZnO-PANi/carbon black thin films have changed into agglomerated
    surface morphology resulting in the increment of porosity of the films.
  7. Prestasi penyahikatan pelarut dengan menggunakan kaedah reka bentuk eksperimen
    Khairul Rijal Jamaludin, Norhamidi Muhammad, Mohd Nizam Ab. Rahman, Murtadhahadi, Sri Yulis M. Amin, Sufizar Ahmad, et al.
    Sains Malaysiana, 2009;38.
    Proses penyahikatan pelarut telah diterima dengan meluas dalam proses pengacuanan suntikan logam (MIM) berdasarkan kemampuannya meningkatkan proses penyahikatan. Bahan pengikat boleh larut yang dikeluarkan dari jasad anum akan menghasilkan liang-liang yang akan membantu meningkatkan kadar penyahikatan terma. Kertas ini membentangkan pengoptimuman proses penyahikatan pelarut dengan menggunakan kaedah Taguchi. Pengaruh pembolehubah penyahikatan pelarut seperti suhu pelarut, taburan saiz partikel, beban serbuk dan tekanan penyuntikan juga dibincangkan. Dua jenis serbuk SS316L digunakan dalam kajian ini iaitu serbuk pengatoman gas dan pengatoman air. Kajian ini mendapati bahawa suhu pelarut memainkan peranan yang sangat penting dalam proses penyahikatan
    pelarut dan menyumbang sebanyak 91.602% (bagi serbuk pengatoman gas) dan 84.978% (bagi serbuk pengatoman air) terhadap kadar pengeluaran bahan pengikat. Bagaimanapun, taburan saiz partikel serbuk hanya menyumbangkan sebanyak 6.638% dan 12.228% bagi serbuk pengatoman gas dan pengatoman air masing-masing terhadap kadar pengeluaran bahan pengikat. Suhu pelarut menunjukkan tahap signifikan yang sangat tinggi iaitu α = 0.005 bagi kedua-dua jenis serbuk tersebut. Walau bagaimanapun, taburan saiz partikel serbuk SS316L menunjukkan tahap signifikan yang sederhana iaitu α = 0.025 dan α = 0.01 bagi kedua-dua padatan serbuk tersebut.
  8. Cloning and analysis of pyrG gene encoding orotidine 5-monophosphate decarboxylase of Aspergillus Oryzae strain S1
    Oh SSL, Leong JM, Abdul Munir Abdul Murad, Farah Diba Abu Bakar, Nor Muhammad Mahadi
    Sains Malaysiana, 2011;40.
    In this study, the pyrG gene which encodes for orotidine 5-monophosphate decarboxylase (OMP decarboxylase) of Aspergillus oryzae strain S1 was cloned and analysed. This 1.8kb A. oryzae pyrG encompasses the 5’-regulatory flanking region (465 bp), open reading frame (899 bp) and 3’-regulatory region (475 bp). The pyrG contained one intron at position 623-687 bp based on the AUGUSTUS and FGENESH (SoftBerry) analysis corresponding to the intron present in the pyrG of A. oryzae (Accession Number: Y13811). In silico analysis showed that the enzyme encoded by the A. oryzae S1 pyrG gene has a theoretical molecular weight of 30.28 kDa and theoretical pI value of 5.92. This enzyme is hydrophilic, located in a region outside of the transmembrane and it functions in the cytoplasm. Five motives such as N-glycosylation site, protein kinase C (PKC) phosphorylation site, casein kinase II (CK-2) phosphorylation site, N-myristolation site and orotidine 5-monophoshate decarboxylase active site have been identified in the pyrG amino acid sequence. The three dimensional structure of this enzyme generated via protein homology modeling using the bioinformatic software, Swiss Model, shows that OMP decarboxylase is a protein with an α/ß barrel structure possessing 8 ß-strands surrounded by 9 α-helices. The amino acid residues involved in the active site have been identified and it is located on one of the ß-strands. The pyrG DNA sequence will be used for the complementation of a pyrG auxotroph mutant of A. oryzae.
  9. Microwave-induced zinc chloride activated palm kernel shell for dye removal
    Muhammad Abbas Ahmad Zaini, Tan Wee Meng, Mohd. Johari Kamaruddin, Siti Hamidah Mohd Setapar, Mohd. Azizi Che Yunus
    Sains Malaysiana, 2014;43:1421-1428.
    This work is aimed to determine the characteristics of activated carbons derived from palm kernel shell (PKS) by microwave-induced zinc chloride activation for dye removal. Activation was performed in a microwave oven at power intensity of 70% for 10 min. The same procedures were repeated for activation using recycled ZnCl2 solution from the first activation. The activated carbons were characterized according to surface area, morphology, functional groups and batch adsorption. The yield for the first activation was 70.7% with surface area of 858m2/g. It was found that the activated carbon prepared using the recycled ZnCl2 still possesses good surface area for methylene blue removal. The adsorption behaviour of the continuous system was well fitted to and could be satisfactorily described by the Yoon and Nelson model.
  10. Fulltext Public facilities guidelines calculator for sustainable housing development
    Norainah Abdul Rahman, Nor Ashikin Ab Manan, Nor Liza Saad, Kamariah Abdullah, Nur Shaffiqa Muhammad Soffian, Aizazi Lutfi Ahmad
    Jurnal Inovasi Malaysia, 2018;1(2):125-144.
    MyJurnal
    Planning guidelines are important tools in controlling the development of housing projects in urban and rural areas to ensure sustainable development (a development that meets the needs of the present, without compromising the ability of future generations in meet their own needs). Planning guidelines are used by local planning authorities (PBPT) to ensure uniformity, comfort and safety in land use activities to achieve effective housing development projects which meet the needs of the communities and create a comfortable living environment. The local planning authorities have developed a set of planning guidelines to be adhered to in all development projects in Malaysia. The main problem of the existing planning guidelines is that they are prepared in the form of reports which are not user friendly. In order to address this problem, a digital version of planning guidelines called the Public Facilities Guidelines Calculator for Sustainable Housing Development is invented. The main objective of this invention is to develop a digital version of planning guidelines which are more user friendly to help the users in accessing the ‘exact’ information ‘easily’ and in an ‘express’ manner (3E’s). The calculator is hoped to be able to provide assistance to town planners, consultants, land developers, and students in preparing the development layout which fulfils the development requirements for planning permission applications. Additionally, the calculator is expected to ease the job of local authorities in determining whether the proposed development layout is aligned with the planning guidelines so that timely planning permission can be issued.
  11. Haid daripada perspektif sains dan Maqasid Syariah
    Nur Asmadayana Hasim, Mohd Izhar Ariff Mohd Kashim, Mohammad Zaini Yahaya, Muhammad Adib Samsudin, Rozida Khalid, Rizafizah Othaman
    Sains Malaysiana, 2016;45:1879-1885.
    Setiap kejadian semula jadi merupakan rahmat dan memberi kemaslahatan kepada manusia termasuklah pendarahan haid dalam kalangan wanita. Haid merupakan suatu proses yang unik dan terancang yang melibatkan tiga fasa utama iaitu fasa haid, fasa folikel dan fasa luteal. Objektif penyelidikan ini ialah untuk mengkaji dan menghubungkaitkan kebaikan haid daripada perspektif sains dan maqasid syariah. Kajian ini dijalankan dengan menggunakan ulasan literatur secara deskriptif. Kajian mendapati bahawa perubahan hormon, warna darah dan faktor fiziokimia lain memberi kesan terhadap kenormalan kitaran haid. Darah haid juga dikenal pasti mempunyai agen antimikrob terutamanya terhadap bakteria E. coli dan bakteria Gram-negatif lain. Hal ini bertepatan dengan maqasid syariah memelihara jiwa kerana haid mampu juga memelihara kesihatan wanita. Selain itu, kajian lepas menemukan bahawa darah haid terdiri daripada sel stem yang boleh digunakan dalam aktiviti klinikal pada masa akan datang. Maqasid syariah melindungi keturunan juga dapat dilihat dengan kehadiran haid yang sering digunakan bagi menjangkakan waktu subur bagi merancang kehamilan. Hikmah Islam melarang mendekatkan diri (bersetubuh) dengan wanita yang sedang haid adalah satu rahmat yang besar, kerana wanita yang sedang haid biasanya mempunyai kelaziman gejala prahaid (PMS) yang melibatkan isu kesihatan. Oleh itu, haid daripada perspektif sains adalah bertepatan dengan maqasid syariah.
  12. Blood plasma in food from islam and science perspectives
    Mohd izhar ariff mohd kashim, Nur asmadayana hasim, Rizafizahothaman, Mohammad zaini yahaya, Rozida khalid, Muhammad adibsamsudin, et al.
    Sains Malaysiana, 2017;46:1779-1787.
    Makanan dan minuman yang halal dan baik merupakan tuntutan dalam Islam. Pada zaman serba moden ini, timbul
    kebimbangan terhadap status halal plasma darah yang digunakan secara meluas terutamanya dalam industri makanan.
    Objektif penyelidikan ini ialah untuk mengkaji kegunaan, kebaikan dan keburukan plasma darah serta pandangan ulama
    mengenai isu ini. Kajian ini dijalankan dengan menggunakan ulasan kepustakaan secara deskriptif. Kajian mendapati
    bahawa plasma darah mempunyai kemampuan melarut dan pengemulsi yang tinggi, kelikatan yang rendah serta
    kemampuan untuk membentuk gel yang kuat. Selain itu, plasma darah boleh menambah baik tekstur dan menjadi pengikat
    dalam penghasilan produk makanan moden. Ia juga merupakan alternatif protein yang murah bagi pengganti lemak dalam
    penghasilan produk daging rendah lemak. Walau bagaimanapun, kajian mendapati plasma darah mengandungi pelbagai
    mikroorganisma dan hasilan metabolisme yang berkemungkinan merbahaya akibat daripada toksin dan protein darah.
    Kini, terdapat pelbagai kaedah pengesanan yang boleh dijalankan untuk mengesan plasma darah dalam makanan bagi
    menentukan status halal. Terdapat dua pandangan berkenaan hukum penggunaan plasma darah, pandangan pertama
    bersependapat, penggunaan plasma darah dalam produk makanan adalah harus jika telah berlaku proses istihalah
    yang sempurna. Manakala pandangan kedua, mengharamkan plasma darah kerana ia adalah proses tidak sempurna
    (istihalah fasidah). Oleh itu, penentuan hukum terhadap istihalah dalam penghasilan plasma darah mestilah menepati
    kehendak syariat Islam di samping memastikan hukum berkaitan isu ini tidak ketinggalan zaman.
  13. Sedimentologi batuan enapan daratan kumpulan gagau (usia kapur awal) di Hulu Sungai Chichir, Terengganu Darul Iman, Malaysia
    Khor WC, Mohd Shafeea Leman, Muhammad Ashahadi Dzulkafli, Kamal Roslan Mohamed, Che Aziz Ali, Jasmi Ab Talib
    Sains Malaysiana, 2017;46:2315-2323.
    Jujukan batuan sedimen Kapur Awal Kumpulan Gagau di kawasan sekitar hulu Sungai Chichir dibentuk oleh batu pasir
    berpebel masif, batu lumpur masif dan lapisan tebal batu pasir dengan pelbagai struktur sedimen serta fosil. Jujukan ini
    boleh dibahagikan kepada tujuh fasies dengan mekanisme pengenapan berbeza. Berdasarkan asosiasi antara pelbagai
    fasies sedimen dapat ditafsirkan bahawa jujukan ini telah terenap dalam pelbagai sekitaran dataran aluvium termasuk
    alur sungai utama, sungai berliku, sungai berburai dan dataran banjir. Fosil yang ditemui memberikan usia Kapur
    Awal kepada jujukan ini. Bukti kehadiran tanah atas di kawasan ini mencerahkan harapan untuk penemuan pelbagai
    fosil hidupan daratan, khususnya fauna vertebrat serta dinosaur yang lebih baik dan lengkap.
  14. Control of microbiologically influenced corrosion using ultraviolet radiation
    Akrima Abu Bakar, Muhammad Khairool Fahmy Mohd Ali, Norhazilan Md. Noor, Nordin Yahaya, Mardhiah Ismail, Ahmad Safuan A. Rashid
    Sains Malaysiana, 2017;46:1323-1331.
    Baram Delta Operation had been producing oil and gas since 1960's and serious pipelines failure was reported in the year of 2005. The final investigation has concluded that one of the species of bacteria that has been identified to cause microbiologically influenced corrosion, specifically known as sulfate reducing bacteria (SRB) was found to be one of the potential contributing factors to the incidents. This work investigates the potential use of ultraviolet (UV) radiation to inhibit the SRB consortium that was cultivated from the crude oil in one of the main trunk lines at Baram Delta Operation, Sarawak, Malaysia. The impact of UV exposure to bio-corrosion conditions on carbon steel coupon in certain samples for 28 days was discussed in this study. The samples were exposed to UV radiation based on variations of parameters, namely: time of UV exposure; and power of UV lamp. The significant changes on the amount of turbidity reading and metal loss of the steel coupon were recorded before and after experiment. The results showed that SRB growth has reduced rapidly for almost 90% after the UV exposure for both parameters as compared to the abiotic samples. Metal loss values were also decreased in certain exposure condition. Additionally, field emission scanning electron microscopy (FESEM) coupled with energy dispersive spectroscopy (EDS) was performed to observe the biofilm layer formed on the metal surface after its exposure to SRB. The evidence suggested that the efficiency of UV treatment against SRB growth could be influenced by the particular factors studied
  15. Origin of formation water salinity variation and its geological significance in Chang 9 Stratum, Jiyuan Oilfield
    Hua Yang, Jinhua Fu, Yujiang Shi, Yumei Cheng, Haitao Zhang, Zhiqiang Mao, et al.
    Sains Malaysiana, 2016;45:9-18.
    The origin of formation water salinity variation in Chang 9 stratum, Jiyuan oilfield, Ordos basin is studied here. 91 formation water samples show that water salinity is characterized by a wide range and a complex plane distribution. In order to find out the main cause of such distribution complexity and reveal the relationship between formation water and evolution of reservoir traps, core data, chemical analysis result of formation water and log data are analyzed from perspectives of diagenesis and tectonism. And then, their characteristics are presented as the followings. In high salinity area, tuffaceous mudstone interlayer is found growing. Besides, the condition of Na++K+ is opposite to that of Ca2+, for its rate of concentration increase slows down with total salinity accumulating. In low salinity area, while, with fracture and faults developing, some formation water of CaCl2 type turns into MgCl2, NaHCO3 or Na2SO4 type. The cause is thus proposed to be composed of two aspects. One covers tuff alteration and later diagenesis for the high salinity. To be specific, montmorillonite, developed from tuff alteration, absorbs cation selectively and then ions migrate, during which more Na++K+ get lost, while more Ca2+ reserved. Afterwards, those reserved Ca2+ get released with montmorillonite transforming to illite, which results in a loss of Na++K+ and accumulation of Ca2+. Lots of ions are released into formation water during that process and later diagenetic process, which leads to the high water salinity. The other aspect is the development of faults and fractures, through which, the upper low salinity formation water gets connected. And that is the main cause of low salinity. At last, geological significance is discussed from two angles. Firstly, tuff alteration and later diagenesis are pivotal to reservoir reconstruction; and secondly, faults and fractures play an important role in oil transportation and storage.
  16. Phytochemical and biological evaluation of Defatted seeds of Jatropha Curcas
    Ul Haq MN, Wazir SM, Ullah F, Khan RA, Shah MS, Khatak A
    Sains Malaysiana, 2016;45:1435-1442.
    In this study, the antimicrobial, antioxidant, phytotoxic and phytochemical properties of defatted seeds of Jatropha curcas were evaluated. A crude methanolic extract of defatted seeds was tested against three fungal strains - Aspergillus niger, Aspergillus flavus and Aspergillus fumigatus - and five bacteria: Escherichia coli and Klebsiella pneumoniae (Gram negative) and Micrococcus luteus, Bacillus subtilis and Staphylococcus aureus (Gram positive). The methanolic extract was diluted in dimethylsulfoxide to final concentrations of 1, 2, 3, 4 and 5 mg/10 mL. The largest zones of inhibition against K. pneumoniae, M. luteus and B. subtilis were achieved using the concentration of 5 mg/10 mL. The concentration of 1 mg/10 mL was most effective against S. aureus and E. coli. In a 1, 1-diphenyl-2-picrylahydrazyl (DPPH) radical scavenging assay, the 5 mg/10 mL concentration of the Jatropha seed extract showed the strongest activity. Higher concentrations of the Jatropha seed extract (10 mg/50 mL and 5 mg/50 mL) significantly inhibited the germination of radish seeds and had negative effects on radish seedling relative water content, shoot length, root length, seedling fresh weight and seedling dry weight (p<0.05). Phytochemical analyses of the defatted seeds detected alkaloids (7.3%), flavonoids (0.39%) and soluble phenolics (mg gallic acid equivalents/g extract). Based on these results, it was inferred that J. curcas seeds contain active ingredients that are effective against pathogenic microbes and therefore could be used to formulate drugs to treat various diseases.
  17. Influence of hydrochloric acid volume on the growth of titanium dioxide (TiO2) nanostructures by hydrothermal method
    Noor Kamalia Abd Hamed, Noor Sakinah Khalid, Fatin Izyani Mohd Fazli, Muhammad Luqman Mohd Napi, Nafarizal Nayan, Mohd Khairul Ahmad
    Sains Malaysiana, 2016;45:1669-1673.
    Titanium dioxide (TiO2
    ) with various morphologies has been successfully synthesized by a simple hydrothermal method
    at 150o
    C for 10 h using titanium butoxide (TBOT) as a precursor, deionized (DI) water and hydrochloric acid (HCl) on
    a fluorine-doped tin oxide (FTO) substrate. The influences of HCl volume on structural and morphological properties
    of TiO2
    have been studied using x-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM),
    respectively. The result showed that several morphologies such as microsphere, microrods, nanorods and nanoflowers
    were obtained by varying the volume of hydrochloric acid. The crystallinity of titanium dioxide enhanced with the
    increasing of hydrochloric acid volume.
  18. Effects of soaking in glycerol and conventional solvents on the grinding of kempas wood (koompassia malaccensis)
    Poh Lee Loh, Noor Azlina Abdul Ghani, Nabilah Suhaili, Zetty Shafiqa Othman, Muhammad Rahimi Yusop, Rizafizah Othaman, et al.
    Sains Malaysiana, 2018;47:1123-1129.
    Glycerol, the main by-product in biodiesel manufacturing, is a useful and environment-friendly solvent for many organic
    and inorganic substrates. This study investigates the effects of soaking using glycerol, silicone oil, dimethyl sulfoxide
    (DMSO) and Organosolv (1:1 water: ethanol) on energy consumption in the process of grinding kempas wood and on
    the particle size of ground kempas. Kempas wood chips were soaked in various solvents at 90°C for 1 h. The structural
    characterisation of untreated and treated kempas was analysed using CHNS, ATR-FTIR and XRD. Meanwhile, the grinding
    energy was calculated based on power per unit time while particle size was analysed using nested column sieves. Glycerol
    has high stability, good compatibility with other chemicals and is environmentally friendly. Glycerol-soaked kempas
    consumed less energy which led to energy saving of up to 0.015 W h and exhibited the smallest average particle size
    (263 µm) close to that of untreated kempas due to glycerol lubricating properties. Therefore, glycerol can be used as
    an alternative to conventional solvents in reducing the grinding energy consumption and particle size of lignocellulosic
    biomass.
  19. Mechanical and bioactive properties of mullite reinforced pseudowollastonite biocomposite
    Farah ‘Atiqah Abdul Azam, Roslinda Shamsudin, Zalita Zainuddin, Muhammad Azmi Abdul Hamid, Min Hwei Ng, Rashita Abdul Rashid
    Sains Malaysiana, 2018;47:2141-2149.
    Bioactive composites consist of pseudowollastonite and mullite synthesized from natural resources was developed for
    bone implant applications. To realize such applications, a mechanical test of these composites and in vitro bioactivity in
    SBF solution were studied. The present paper reports pseudowollastonite synthesized from the rice husk ash and limestone
    reinforced with 10, 20 and 30 wt. % of mullite. Influence of sintering temperature, phase composition, morphology towards
    mechanical properties of various pseudowollastonite-mullite (PSW-M) composites was examined prior to the bioactivity
    test. It was found that pseudowollastonite with the addition of 20 wt. % of mullite sintered at 1150°C gave the best result
    for diametral tensile strength (DTS) and hardness with the value of 8.8 ± 0.15 MPa and 3.79 ± 0.13 GPa, respectively.
    The obvious increment in the mechanical strength was due to the formation of liquid phase CaAl2
    O3
    during sintering at
    1150°C. In addition, the formation of fibrous apatite (HA) layer of amorphous calcium phosphate (ACP) with Ca/P ratio
    1.8 on PSW20M sample confirmed the good bioactivity of the composite.
  20. Transforming growth factor beta 3 induced human adipose-derived stem cells for auricular chondrogenesis
    Siti Nurhadis Che Omar, Kien-Hui Chua, Bee See Goh, Muhammad Azhan Ubaidah, Lokman Saim, Khairul Anuar Khairoji, et al.
    Sains Malaysiana, 2018;47:2349-2358.
    The limitation of self-repair and proliferation capacity of chondrocytes in cartilage reconstruction lead to alternative
    search of cell source that can improve the auricular regeneration. Human adipose-derived stem cells (HADSC) are an
    alternative cell source that have unique characteristics to self-renew and differentiate into various tissues making it
    suitable for cell therapy and tissue engineering. This study aimed to examine the chondrogenic differentiation potential of
    (HADSC) in monolayer culture by the presence of different transforming growth factor beta’s, TFG-β1, -β2 and -β3. HADSC
    at passage 3 (1.5 × 105 cell/mL) were cultured in chondrogenic medium containing 5 ng/mL of different transforming
    growth factor beta’s, TFG-β1, -β2 and -β3 for 7, 14 and 21 days. Data analysis was evaluated based on the growth
    rate of cells, cells morphological changed, production of collagen type II and glycosaminoglycan sulphate (sGAG). The
    quantitative RT-PCR was carried out to determine the chondrogenic, fibrogenic and hypertrophic gene expression levels.
    Differentiation of HADSC into chondrocytes using TFG-β indicates the occurrence of the chondrogenesis process. The best
    chondrogenic differentiation was observed in HADSC induced by TFG-β3 through the chondrocytes-like cells morphology
    with cells aggregation and high production of proteoglycan matrices compared to other TGF-βs groups. Additionally,
    the expression of chondrocytes-specific genes such as Type II collagen, Aggrecan core protein, Elastin and Sox 9 was
    high. In conclusion, this study has showed that TGF-β3 is the potential growth factor in producing chondrogenic cells
    for auricular cartilage tissue engineering.
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