The effects of annealing parameters on crystallinity and surface morphology of RF sputtered zinc oxide nano films were investigated. The structure and morphology of the nano films were dependent on temperature, gas flow rate and time of annealing. The results from atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) showed smooth and uniform growth of c-axis orientation films with an average grain sizes from 10 to 30 nm. Increments of the annealing temperature from 400 to 800°C led to bigger grain size, better crystallinity and also increase of the surface roughness. Moreover, the results showed that the crystallinity was independent of the annealing time up to 40 min after starting the annealing process. Increase in the percentage of oxygen in the O/Ar (mixture of annealing gases) from 50% to 100% results in no changes in AFM results, but XRD revealed that the (100) peak intensity was decreased, the position of (002) peak was slightly shifted towards higher angle and FWHM of (002) peak was improved.
Countering the dangers associated the present extreme climate not only requires continuous improvement of local disaster
prevention engineering infrastructure but also needs an enhanced understanding of the causes of the disasters. This study
investigates the geologic hazard risk of 53 slopeland villages in Pingtung county of southern Taiwan. First, remote sensing
(RS) techniques were utilized to interpret environmental geology and geologic hazard zonation, including dip slope, fault,
landslide and debris flow. GIS map overlay analysis was used to further identify the extent of the geologic hazard zonation.
As a final step, field investigation is used to comprehend geologic, topographic conditions and the geologic hazard risk
specific to each locality. Based on data analysis and field investigation results, this study successfully integrates RS, GIS
and GPS techniques to construct a geologic hazard risk assessment method of slopeland village. The results of this study
can be used to promote support for future disaster prevention and disaster mitigation efforts.
Obesity is a multifactorial disease caused by the interaction of genetic, lifestyle and environmental factors. Common single nucleotide polymorphisms in the recently-described Fat Mass and Obesity-Associated (FTO) gene have been related to body weight and fat mass in humans and genome-wide association studies in several populations have indicated that the FTO rs9939609 variant is associated with obesity. Therefore, the objective of this study was to investigate the association of the FTO rs9939609 variant with obesity among 324 multi-ethnic Malaysians (98 Malays, 158 Chinese, 68 Indians) who attended the Kampar Health Clinic, Perak. With the overall minor A allele frequency (MAF) of 0.199, the distribution of genotypes and alleles was significantly different among ethnicities (MAF highest among Malays), but no association was found for obesity, related anthropometric measurements and gender. Subject with allele A had marginally but significantly higher waist circumference (p=0.015), thus the FTO rs9939609 allele was associated with central obesity [p=0.034 by Chi-square analysis; Odds Ratio (OR)=1.680 (CI=1.036, 2.724; p=0.035)]. However, this association was abolished when adjusted for age, gender and ethnicity (OR=1.455, CI=0.874, 2.42; p=0.149). In conclusion, the MAF of the FTO rs9939609 SNP was low as in other Asian populations and there was no evidence for an involvement of this SNP in obesity and obesity-related traits in this multi-ethnic Malaysian study group.
Adunan polietilena berketumpatan rendah (LDPE)/getah asli cecair (LNR) dalam komposisi 100LDPE/0LNR, 70LDPE/30LNR, 60LDPE/40LNR dan 40LDPE/60LNR telah dihasilkan melalui penyebaran emulsi LDPE dan LNR.. LNR diperolehi melalui tindak balas pemekaan fotokimia ke atas getah asli (NR) dan emulsi LNR disediakan dengan menggunakan natrium dodesil sulfat (SDS) sebagai agen pengemulsi dan 1-heksanol sebagai ko-pengemulsi. Emulsi LDPE dihasilkan dengan cara yang sama menggunakan larutan LDPE dalam karbon tetraklorida, SDS dan 1-heksanol. Adunan LDPE/LNR disediakan melalui pencampuran emulsi LNR dan LDPE. Sifat mekanik adunan LDPE/LNR dianalisis melalui ujian regangan, hentaman dan kekerasan. Sifat mekanik optimum diperhatikan bagi adunan dengan komposisi 60LDPE/40LNR yang memberi nilai tegasan dan terikan yang maksimum. Suhu peralihan kaca, Tg, seperti yang diperolehi daripada analisis kalorimetri imbasan pembezaan (DSC) menunjukkan adunan yang dihasilkan adalah homogen. Kajian morfologi yang dilakukan dengan menggunakan mikroskop imbasan elektron (SEM) juga menunjukkan kehomogenan adunan yang dihasilkan.
Chlorella vulgaris (ChV), sejenis alga hijau unisel telah dilaporkan mempunyai khasiat kesihatan pada penyakit tertentu termasuk kanser. Objektif utama kajian ialah untuk mengukur dan menilai kesan antioksidan dan antitumor ekstrak air panas ChV ke atas sel kanser hepar yang dijalankan secara in vivo dan in vitro. Asai DPPH yang dijalankan menunjukkan peratus pengautan ChV yang tinggi. Dalam kajian in vivo, tikus Wistar jantan (200-250 g) dibahagikan kepada lapan kumpulan: tikus kawalan (diet normal), tikus diaruh kanser hepar (diet kurang kolin + 0.1% etionin dalam air minuman) atau singkatannya CDE, tikus diberi rawatan ChV pada tiga dos berbeza (50, 150 dan 300 mg/kg berat badan) dan tikus CDE diberi rawatan ChV pada tiga dos berbeza. Sampel darah dan tisu diambil dari semua kumpulan tikus pada minggu 0, 4, 8 dan 12 untuk penentuan kadar proliferasi dan apoptosis sel untuk melihat kesan antitumor ChV. Peratus pembentukan nodul praneoplasia adalah tinggi pada tikus diaruh kanser hepar (CDE) tetapi ChV pada semua dos berjaya mengurangkannya. Pertambahan jumlah sel kanser semasa hepatokarsinogenesis ditunjukkan dengan peningkatan proliferasi hepatosit yang signifikan (p<0.05) pada tikus CDE berbanding kawalan tetapi ChV pada semua dos berjaya mengurangkan proliferasi secara signifikan (p<0.05). Peratus apoptosis sel didapati meningkat secara signifikan (p<0.05) pada tikus CDE, tetapi peningkatan yang lebih ketara berlaku pada tikus CDE diberi ChV (300 mg/kg berat badan). Dalam kajian in vitro pula, aktiviti antitumor ekstrak air panas ChV telah ditentukan dengan melihat perubahan dalam proliferasi dan apoptosis sel kanser hepar HepG2 yang dikultur di makmal. Ekstrak air panas ChV berjaya menurunkan kadar proliferasi sel HepG2 dengan signifikan secara berkadar terus dengan dos yang digunakan dengan nilai IC50 1.6 mg/ml. Hasil analisis TUNEL pula menunjukkan ekstrak air panas ChV berjaya mengaruh apoptosis dalam sel HepG2. Keputusan ini disokong oleh hasil pemblotan Western dengan peningkatan pengekspresan protein P53 dan protein proapoptosis BAX dan Kaspase-3. Daripada hasil-hasil kajian, dapatlah dicadangkan bahawa ChV berpotensi tinggi sebagai antioksidan serta berupaya memberi kesan antitumor kepada kanser hepar pada kajian in vivo dan in vitro.
Fifty three samples of different types of imported and locally produced drinks consumed in the central zone of Malaysia were analyzed using gamma-ray spectrometry system equipped with a high purity germanium (HPGe) detector. The activity concentrations of the natural radionuclides 238U, 232Th and 40K present in the studied samples were measured and the radium equivalent activities Raeq were calculated. In addition, the radiation hazard index (HI) was calculated. The
average concentrations of 238U, 232Th and 40K were 0.69 ± 7×10¯4 ,1.3 ± 8×10¯4 and 20.52 ± 6×10¯4 Bq/Kg, respectively. The values of Raeq were between 0.002 and 10.0 Bq/kg. The HI were between 0.002 and 0.03, which is below one (the higher limit of HI). The results obtained were compared to the standard accepted international values and found to be within the acceptable limits.
The use of cell lines such as Madin-Darby Canine Kidney (MDCK) and African Green Monkey Kidney (Vero) cells in
influenza vaccine production is much advocated presently as a safer alternative to chicken embryonated eggs. It is
thus essential to understand the influenza virus replication patterns in these cell lines prior to utilizing them in vaccine
production. The infectivity of avian influenza A virus (A/Chicken/Malaysia/5858/2004) H5N1 in MDCK and Vero cell
lines was first assessed by comparing the cytopathic effect (CPE) caused by the virus infection. The viral loads in both
of the infected media and cells were also compared. The results showed that both of the MDCK and Vero cells began to
exhibit significant CPE (p<0.05) after 48 h post-infection (h p.i). The MDCK cell line was more susceptible to the virus
infection compared to Vero cell line throughout the incubation period. A higher viral load was also detected in the host
cells compared to their respective culturing media. Interestingly, after reaching its maximum titer at 48 h p.i, the viral
load in MDCK cells declined meanwhile the viral load in Vero cells increased gradually and peaked at 120 h p.i. Overall,
both cell lines support efficient H5N1 virus replication. While the peak viral loads measured in the two cell lines did
not differ much, a more rapid replication was observed in the infected MDCK samples. The finding showed that MDCK
cell line might serve as a more time-saving and cost-effective cell culture-based system compared to Vero cell line for
influenza vaccine production.
In this study, heavy metal data (including four geochemical fractions) from offshore and intertidal sediments collected off the west coast of Peninsular Malaysia were analyzed using factor analysis. A similarity was found when comparing between offshore and intertidal sediments, where out of the 20 variables, five factors (resistant Cu, total Cu, resistant Pb, total Pb and total Zn) could be clearly selected on the basis of their high loadings as derived by factor analysis in both sediment sampling areas. However, the statistical outputs based on the present study using factor analysis cannot be practically acceptable mainly because the resistant fractions are not of anthropogenic origins and ecotoxicologists are more concern on the anthropogenic ones. Only a modification using a specific normalizing agent such as the nonresistant fraction, should be tested to show feasibility of the contribution of anthropogenic sources in the two sampling areas. However, a more comprehensive metal monitoring data should be compiled to complement the results obtainable from factor analysis, before a valid Malaysian Marine Sediment Pollution Index or Sediment Quality Guidelines, can be proposed to be established.
A study was conducted to differentiate fractionated components of lard namely lard olein (LO) and lard stearin (LS) from other common animal fats. Lard fractions and animal fats were analyzed using differential scanning calorimetry (DSC), elemental analyzer–isotope ratio mass spectrometry (EA-IRMS), gas chromatography mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR). Overlay of FTIR spectra did not help to pinpoint any characteristic feature to distinguish either LO or LS from other animal fats, but overlay of DSC cooling curves helped a successful discrimination. The determination of δ13C from EA-IRMS showed that the values corresponding to the fractionated components of lard were significantly (p<0.05) different from those of the other common animal fats. GC-MS analysis showed that direct comparison of overall fatty acid data was not able to discriminate LO and LS from other animal fats, but the application of principal component analysis (PCA) to fatty acid data helped a successful discrimination.
Loji rawatan kumbahan (STP) sedia ada khususnya di Malaysia tidak direka untuk menyingkirkan bahan farmaseutik yang
tergolong dalam kategori bahan cemar baru muncul. Oleh kerana farmaseutik yang hadir dalam persekitaran akuatik
ialah pada kepekatan yang sangat rendah iaitu dalam julat bahagian per bilion dan trilion, satu kaedah pengekstrakan
dan analisis yang peka perlu dibangunkan. Dalam kajian ini, kaedah analisis berdasarkan pengekstrakan fasa pepejal
(SPE) diikuti dengan kromatografi cecair-spektrometri jisim masa penerbangan (LC-TOF-MS) menggunakan mod pengionan
secara semburan elektro positif telah berjaya dibangunkan untuk menentukan kehadiran sepuluh farmaseutik terpilih
dalam air kumbahan dan air sungai. Farmaseutik yang dikaji termasuk acetaminophen, theophylline, caffeine, metoprolol,
sulfamethoxazole, carbamazepine, prednisolone, ketoprofen, norgestrel dan simvastatin. Kaedah SPE menggunakan
langkah pengekstrakan tunggal yang menggunakan isi padu sampel yang rendah sebanyak 100 mL dan pelarut elusi
yang minimum telah berjaya dicapai. Peratus perolehan semula untuk kesemua farmaseutik dalam sampel air sungai
berada dalam julat 54-99% manakala bagi sampel efluen STP pula berada dalam julat 57-96%. Jangka masa analisis
LC-TOF-MS termasuk masa imbangan adalah selama 25 min dengan menggunakan suntikan sampel 20 μL. Prosedur SPE
bersama-sama dengan kaedah analisis yang telah dibangunkan menghasilkan had kuantifikasi (LOQ) dalam lingkungan
0.031-0.882 μg/L untuk sampel STP dan 0.030-0.926 µg/L untuk sampel air sungai.
New organotin(IV) sec-butylpropyldithiocarbamate complexes have been sucÂcessfully synthesized by the reaction between N-sec-butyl-N-propylamine, carbon disulfide and organotin(IV) chloride (dimethyltin(IV), dibutyltin(IV) and triphenyltin(lV) chloride) using in-situ method. All the complexes have been characterized using elemental analysis, gravimetric analysis, infrared and NMR (1H and I3C) spectroscopy. Elemental and gravimetric analyses showed that the complexes agree with the suggested formulae, R2Sn[S2CN( sÂC4H9)(C3H7)]2 dan R‘3Sn[S2CN(s-C4H9)(C3H7)] (R = CH3 or R = C4H9; R' = C6H5 The presence of the v(C = N) and v(C = S) bands in the infrared spectra confirmed the presence of dithiocarbamate ligand in that complex. The 13C NMR spectra for all the complexes showed a resonance in the region 196.22 - 200.62 ppm, which is attributed to the carbon atom of NCS2 group. The dimethyltin(lV) sec-butylpropyldithiocarbamate, Me2Sn(SBPDtc)2 was recrystallized from CHCl3 and the structure had been determined using X-ray crystallography analysis. The structure of Me2Sn[s-C4H9)(C3H7)]2 is found to be in the monoclinic system with space group P21/n, a = 14.358(2), b = 10.6956(18), c = 17.323(3) Ã…; α = 90°, β = 99.765(4)°, γ = 90°. The complex is six-coordinated with the tin atom bonded by two dimethyl groups in cis positions and two chelating sec-butylpropyldithiocarbamates in bidentate mode.
Kompleks baru organostanum(IV) sek-butilpropilditiokarbamat telah berjaya disediakan melalui tindak balas di antara N-sek-butil-N-propilamina, karbon disulfida dan sebatian dimetilstanum(lv), dibutilstanum(IV) dan trifenilstanum(IV) klorida menggunakan kaedah in-situ. Kesemua kompleks telah dicirikan menggunakan analisis unsur, analisis gravimetri, spektroskopi inframerah dan spektroskopi resonans magnet nukleus 1H dan 13C. Analisis unsur (CHNS) dan gravimetri menunjukkan sebatian yang disintesis bersetuju dengan formula yang dicadangkan, iaitu R2Sn[S2CN(s-C4H9)(C3H7)]2 dan R'3Sn[S2CN(s-C4H9)(C3H7] (R = CH3 atau C4H9; R' = C6H5). Kehadiran jalur serapan v(C ---- N) dan v(C ---- S) pada spektrum inframerah menunjukkan kehadiran ligan ditiokarbamat dalam sebatian yang disediakan. Spektrum RMN I3C bagi ketiga-tiga kompleks menunjukkan resonan N13CS2 terletak pada julat 196.22- 200.61 ppm. Kompleks dimetilstanum(1V) sekÂbufilpropilditiokarbamat telah berjaya dihablurkan menggunakan pelarut kloroform. Kajian kristalograji sinar-X menunjukkan hablur Me2Sn[s-ÂC4H9)(C5H7)]2 bersistem monoklinik dengan kumpulan ruang P21/n, a = 14.358(2), b = 10.6956(18), c = 17.323(3) Ã…; α = 90°, β= 99.765(4)°, γ = 90°. Kompleks membentuk geometri enam koordinat dengan atom pusat stanum yang berikat dengan dua kumpulan metil pada kedudukan sis dan mengkelat secara bidentat dengan ligan sek-butil propilditiokarbamat.
Aluminium in drinking water comes from natural sources and the alum used as coagulant in the water treatment process. Exposure to aluminium has been implicated in dialysis dementia, Parkinson and Alzheimer’s disease. Drinking water containing aluminium was considered to be one of the main sources of Al intake into human body. For this reason, the removal of aluminium from drinking water is vital to our health. In this study, removal of aluminium was carried out by using a chelating resin. To achieve the purpose, two chelating resin iontosorb oxin (IO) and polyhydroxamic acid (PHA) were used. The effects of concentration, pH, stirring time and resin amount was investigated. The concentration range varied between 10 and 500 ppb, pH range was between 2 and 12, stirring time between 5 and 60 minutes, and resin amount between 100 and 1500 mg. The optimum conditions of these resins were determined in a batch system. The results obtained showed that the optimum condition to remove aluminium for polyhydroxamic acid and iontosorb was pH 5-8 and pH 4-9; concentration range between 50-500 ppb, and 150-500 ppb, resin amount 200 mg and the stirring time was 20 minutes, respectively.
Magnetic paper were prepared via the in situ synthesis method with ferrites in the presence of polyethylenimine (PEI). In this work, the thermomechanical pulp (TMP) fibers were used due to low percentage of collapse lumen and the large lumen size for optimum loading degree. Four cycles of the reaction were performed on the TMP fibers with pH values of 4-10. It was found that variation of pH value played an important role in the loading degree of pulp during synthesis process. The magnetic, morphological and structural properties of the magnetic paper obtained were reported. At the
optimum pH of 6.0, saturation magnetization was found to be 3.08 emu/g, remainance magnetization was 0.11 emu/g and coercive force was 12.64 Oe. The optimum loading degree was found to be 23.25%.
Veronica scutellata L. occurs in moist and wet habitats, such as ponds, marshes and other wetlands. This study was conducted on this species to examine its mineral element uptake status in terms of interactions between soil and plant. Experimental materials were taken from the Southern coast of Black Sea at coordinates 40º36’N and 31º16’E at an altitude of 1400 m above sea level from Bolu – Turkey; using standard methods and plant (root, stem and leaf parts) and soil mineral element measurements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, Ni and Zn) were done. During the study, ICP-OES was employed for the measurement of mineral elements. It was observed that considerable amounts of B, Ca, K, Mg, Mn, Na and Zn are accumulated by the plant.
Polymer gel electrolytes (PGEs) based on 49% methyl-grafted natural rubber (MG49) were first prepared by dissolving ammonium triflate (NH4CF3SO3) in propylene carbonate (PC) by various molar concentrations of NH4CF3SO3 to obtain liquid electrolytes and were characterized by AC electrical impedance spectroscopy (EIS) measurements to study their conducting behaviour. The liquid electrolyte with optimum conductivity (0.7M) was then gelled with MG49 and their conductivity was also studied. The highest conductivity of liquid electrolyte was 3.6×10-3 Scm-1 and 2.9×10-2 Scm-1 for PGEs. The molecular interactions between components of NH4CF3SO3, PC, and MG49 have been observed by ATR-FTIR spectroscopy study. The downshifting of C=O stretching frequency of PC from 1785 cm-1 to 1780 cm-1 and NH4+ band from 1634 cm-1 to 1626 cm-1 that has been obtained by spectroscopic data in addition of NH4CF3SO3 confirmed the complexation occurrence. Interaction between NH4CF3SO3 and MG49 has also been investigated. This study is focused on the interactions between components in the PGE system and relates them with their conducting behavior.
In the original ElGamal signature scheme and it’s variants, two secret integers-private key and one-time secret key are required to produce a signature on a message, m. The private key of a system will be used throughout the life of the system whereas the one-time secret key only be used once and must be regenerated (different one-time secret key) when signing different message. This paper introduces a new version of ElGamal signature that eliminates the use of one-time secret key. This property will make all attacks, aiming at revealing the one-time secret key irrelevant. The scheme also can be regarded as ‘a right notion of signature scheme’ because we use only one secret key to sign messages.
Titanium dioxide (TiO2), porphyrin and TiO2 coated with dye porphyrin thin films were prepared on Quartz Crystal Microbalance (QCM) using sol-gel dip coating method and were tested for sensing of volatile organic compounds (VOCs). The porphyrin used was 5,10,15,20-tetraphenyl-21H,23H-porphine manganese (III) chloride (MnTPPCl). The sensing sensitivity was based on the change in the fundamental frequency of the QCM upon exposure towards six vapor samples, namely ethanol, acetone, cyclohexane, toluene, o-xylene and 2-propanol. It was found that all the thin films were sensitive towards all the vapors. However, the TiO2 coated MnTPPCl thin film exhibit the most sensitive and has good selectivity property.
Kanji Dioscorea pentaphylla telah diubah suai dengan pensulfatan dan peneutralan bagi menghasilkan natrium
kanji sulfat. Tindak balas pensulfatan dilakukan dengan asid sulfurik dalam etanol dan air pada suhu 0o
C. Darjah
penukargantian dikira berdasarkan peratus karbon dan sulfur yang ditentukan menggunakan penganalisis unsur CHNS.
Natrium kanji sulfat yang mempunyai darjah penukargantian dan peratus nisbah berat hasil yang tinggi dipilih dan
dicirikan dengan spektrum transformasi Fourier inframerah (FT-IR) dan profil pembelauan sinar-X (XRD). Kehadiran
dua puncak getaran regangan C-O-S dan S=O dalam spektrum FT-IR dan puncak berbeza yang terhasil dalam corak
difraktogram XRD membuktikan tindak balas berlaku pada struktur kanji. Sifat termal juga ditentukan dengan kalorimeter
pengimbas pembezaan (DSC) dan analisis termogravimetri (TGA). Natrium kanji sulfat yang dihasilkan mempunyai
kestabilan termal yang baik kerana mempunyai suhu penguraian pada 265o
C. Natrium kanji sulfat ini sesuai dijadikan
bahan tambahan dalam penghasilan hidrogel, organogel dan filem dengan sifat anionik kerana degradasi tidak terjadi
di bawah suhu ini.
Satu kajian telah dijalankan untuk menguji kesan sitotoksik dan aktiviti antibakteria ekstrak metanol dari bahagian berbeza tumbuhan Phyllanthus gracilipes dan P. columnaris. Pengekstrakan dilakukan pada suhu bilik dan menggunakan alat-radas Soxhlet untuk menghasilkan 22 ekstrak. Ujian fitokimia ke atas ekstrak Soxhlet menunjukkan kehadiran saponin dalam semua ekstrak manakala steroid terdapat dalam ekstrak semua bahagian P. gracilipes dan 3 daripada ekstrak P. columnaris. Ujian sitotoksik ke atas kultur sel Vero menunjukkan hanya empat ekstrak yang sitotoksik dengan nilai LC50 di bawah 20 μg/mL iaitu ekstrak suhu bilik kulit-batang P. gracilipes, ekstrak Soxhlet kayu-batang dan daun P. gracilipes serta ekstrak suhu bilik kayu-akar P. columnaris. Ekstrak suhu bilik dan Soxhlet kayu-batang P. gracilipes serta semua ekstrak suhu bilik P. columnaris merencat pertumbuhan 13 pencilan Staphylococcus aureus Rintang-Metisillin (MRSA) yang diuji.
This study investigated the elemental composition of pathological and normal nails, according to different age groups
and genders. The nail elemental composition was analyzed by using Laser Induced Breakdown Spectroscopy (LIBS)
technique. A Q-switched Nd:YAG laser at 1064 nm with output energy of 100 mJ, pulse duration of 6 ns and repetition
rate of 1 Hz was fired to the human nails sample. The laser pulse ablated the target sample surface and produced plasma
plume with characteristic spectral line comprising sample’s elemental composition. The plasma emission spectrum of
nail samples were captured by fibre optic detection device and spectrometer equipped with ASEQ Spectra Software for
elemental analysis. The elements detected in nails were Mg, Al, Ca, P, Ti, K and Na. Classification of nails into different
age groups and genders demonstrate efficient results if compared with Dietary Reference Intakes (DRI). The results
indicate that Ca, Al, Ti, P and K composition were higher among female. However, Mg and Na were higher among
male. The results also show that Ca and K element decline as the age increase in both genders. The pathological nails’
elemental compositions were also noticeably related to the nail disorder condition itself. It is proven that LIBS could be
a possible method for analyzing the nails and identification of various nail disorders.