ABSTRACT
Triclopyr is a post emergence herbicide used to control woody plants. After application, the excess amount will enter the soil and water bodies and it is present in ppb level thus making extraction very difficult. The extraction of triclopyr 3, 5, 6-trichloro-2-pyridinyl residue from soil, sediment and water samples under different solid phase extraction (SPE) sorbent efficiency was studied for better recovery. Four different SPE sorbents i.e.: Oasis HLB, Water Sep-Pak, Cromabond (cation/anion PS-H+ /OH-), Isolute ENV+ and a series of solvent i.e. potassium dihydrogen phosphate (KH2PO4 0.1M), sodium hydroxide (NaOH 0.2M), potassium hydroxide (KOH 0.5 & 0.6M), ammonium acetate, methanol and water were used as extraction solution. Sample clean-up performance was evaluated using high performance liquid chromatography (HPLC, Agilent 1220 infinity LC) with variable wavelength detector (VWD) 290 nm. Cromabond®H+/OHcolumn with 0.6 M KOH was the most suitable for the clean-up in view of the overall feasibility of the analysis. The highest recovery was 89.32%.
A study was carried out to determine the diversity and enumerate the fauna species related to five pitcher plant species at a selected area in Bukit Setiam Forest, Tatau, Bintulu, Sarawak, Malaysia. At the end of the study, six insect orders together with nematodes and Araneae were detected with different existence abundances and diversity. From the 901 total fauna trapped, 58.82% belonged to the order Hymenoptera, mainly of the ant species, followed by Nematodes (21.64%), Diptera (15.87%), Coleoptera (1.66%), Hemiptera (0.89%), Blattaria (0.44%) and finally, Lepidoptera (0.33%) and Araneae (0.33%). Significant differences (p<0.05) in the composition of insect trapped in pitcher plants were observed for the order Hymenoptera, Diptera, Lepidoptera, Hemiptera and even Nematodes. Meanwhile, no significant difference was observed for Coleoptera, Blattaria and Araneae. There is a strong relationship between fauna and Nepenthes pitcher either as a prey, predator, a mutualistic relationship or parasites or also for a habitat to live or to reproduce.
By using sequences of linear maps on C*-algebras, we consider sets known as Korovkin sets, i.e. sets of the form
{a ε Asd/фn(a) → фo(a), фn(a2)→ фo (a2) = фo (a)2} In this paper we prove that if {фn} is a sequence of weak Kadison maps and '→' means norm, strong or weak convergence, then the Korovkin sets are JC-algebras. Furthermore if we assume that {фn} is a sequence of Schwarz maps or anti-Schwarz maps respectively, then the Korovkin sets become reversible JC-algebras.
Dengan menggunakan beberapa jenis jujukan pemetaan linear {фn} atas aljabar-C*, kita pertimbangkan set yang dikenali sebagai set Korovkin, i.i. set berbentuk {a ε Asd/фn(a) → фo(a), фn(a2)→ фo (a2) = фo (a)2} Dalam kertas ini ditunjukkan bahawa jika {фn} adalah jujukan pemetaan Kadison lemah dan penumpuan '→' menandakan penumpuan norma, kuat atau lemah, maka set Korovkin adalah aljabar-JC. Dengan andaian yang lebih kuat, i.i. {фn} masing-masing jujukan Schwarz atau anti-Schwarz, ditunjukkan bahawa set Korovkin merupakan aljabar-JC berbalik.
Macrobrachium lanchesteri dewasa telah didedahkan selama empat hari di dalam makmal kepada satu siri kepekatan logam kuprum (Cu) dan nikel (Ni). Masa kematian median (LT50) dan kepekatan kematian median (LC50) dikira berdasarkan data kematian yang diperolehi. Di akhir hari yang ke-4, udang yang masih hidup digunakan untuk penentuan biopemekatan logam. Nilai LT50 dan LC50 didapati meningkat dengan pengurangan kepekatan dan masa pendedahan bagi kedua-dua logam (Cu dan Ni). Nilai LC50 untuk 24, 48 dan 96 jam bagi Cu masing-masing adalah 261.6, 171.6 dan 32.3 μg/L dan bagi Ni 30786.3, 28534.7 dan 8056.6 μg/L. Biopemekatan logam Cu dan Ni oleh M. lanchesteri meningkat dengan peningkatan kepekatan pendedahan dan logam Cu didapati lebih toksik terhadap M. lanchesteri berbanding logam Ni.
Biomonitor Multispesies Air Tawar (Multispecies Freshwater Biomonitor®) (MFB) menggunakan pengukuran dan analisis pelbagai kelakuan daripada pelbagai jenis organisma akuatik untuk memantau kualiti air dalam ekosistem air tawar. Kajian ini dijalankan di dalam makmal bagi menentukan respons spesifik udang air tawar (Macrobrachium lanchesteri) dan ikan gapi (Poecilia reticulata) terhadap logam berat kadmium (Cd). Kepekatan Cd yang berbeza didedahkan kepada M. lanchesteri (1 ppb dan 10 ppb) dan P. reticulata (100 ppb dan 560 ppb) dan perubahan perilaku setiap organisma direkod dengan MFB selama 2 jam. Hasil yang diperolehi menunjukkan peningkatan respons pergerakan dan ventilasi udang air tawar dan ikan dengan peningkatan kepekatan pendedahan kepada logam Cd. Kajian ini menunjukkan udang memberi respons yang lebih sensitif kepada logam Cd berbanding ikan gapi dan spesies tempatan ini sesuai digunakan sebagai organisma penunjuk untuk MFB.
Masalah pencemaran sumber air tawar dan kesan ketoksikan logam telah mendapat perhatian di serata negara. Dua
spesies organisma air tawar daripada filum moluska Filopaludina sumatrensis dan Corbicula fluminea didedahkan
kepada tiga logam terpilih iaitu arsenik (As) kromium (Cr) dan selenium (Se) pada kepekatan berbeza selama 96 jam di
dalam makmal terkawal. Kadar kematian dinilai serta kepekatan kematian median (LC50) dan masa kematian median
(LT50) dihitung. Nilai LC50 dan LT50 didapati menurun dengan pertambahan masa dan kepekatan pendedahan bagi
kedua-dua spesies dan kesemua logam. Keputusan daripada kajian ini memperlihatkan ketoksikan logam As, Cr dan Se
semakin meningkat dengan peningkatan kepekatan dan masa pendedahan logam kepada F. sumatrensis dan C. fluminea.
Nilai LC50 96 jam As, Cr dan Se bagi F. sumatrensis adalah 4.22, 3.78 dan 45.92 mg/L dan 11.84, 2.23 dan 35.63 mg/L
masing-masing bagi C. fluminea. Keputusan menunjukkan Cr adalah logam paling toksik terhadap F. sumatrensis dan
C. fluminea. Trend ketoksikan logam bagi kedua-dua moluska ini adalah sama iaitu Cr > As > Se.
Twenty (n=20) beef isolates of Escherichia coli O157:H7 were examined for the detection of Shiga- toxin 1 and 2 (stx1 and stx2) genes by multiplex polymerase chain reaction (PCR) and characterized using Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) fingerprinting. All isolates were obtained from the laboratory of Food Science and Biotechnology, University Putra Malaysia, Serdang, Selangor. In the detection of stx1 and stx2 genes, 14 of isolates (14/20) were positive to stx1 and stx2. 5 isolates (5/20) were positive to stx1 and 1 isolate (1/20) was negative by either of stx1 or stx2 genes. Using RAPD-PCR analysis, two oligonucleotides were chosen because they yielded clearly and reproducible band. There were OPAR8 (5’-TGGGGCTGTC-3’) and OPAR20 (5’-ACGGCAAGGA-3’). Subsequently, all 20 isolates of E.coli O157:H7 were subtyped using OPAR8 and OPAR20. Primer OPAR8 produced 8 RAPD-PCR fingerprinting namely P1 to P11. Whereas, OPAR20 produced 16 RAPD-PCR fingerprinting of Q1-Q18. Combination of two primers was analyzed using Unweighted Pair Group Method with Arithmetic mean (UPGMA). Dendogram performed from cluster analysis showed that all the 20 isolates of E.coli O157:H7 differentiated into 20 individual isolates which may suggest the high level of local geographical genetic variation.
Growing needs, inadequate supply along with health and religious issues are reasons for the increase in the demand for an alternative source of gelatine in the food and pharmaceutical industries. This study was conducted to optimize the process for producing halal-compliance gelatine from chicken waste; chicken shank and toes (CST). Double extraction process employed produced gelatine which was vitreous, lightweight and gossamer in appearance. Gelatine yield was 9.52%(w/w) with a pH of 3.85, moisture content of 7.17%, total protein content of 93.77%, total fat content of 0.93% and total ash of 1.57%. The Bloom strength of the CST gelatine (148.33 ± 5.51) was found to be slightly lower than the commercially available bovine gelatine (BS) (169.33 ± 58.53) (P > 0.05). Amino acid analysis showed that the CST gelatine (91.38 ± 1.01%) was comparable to BS gelatine (90.65 ± 1.56%)(P > 0.05). Double extraction has been shown to successfully increase the surface area to volume ratio of CST waste resulting in increased yield in gelatine and protein with lower total fat content obtained. The test results obtained showed that the CST gelatine produced through this method complies with pharmaceutical standards.
Thirteen formulations of cinnamaldehyde/non-ionic surfactant/water system nanoemulsions were prepared using highpressure homogenisation. The result showed that varying the cinnamaldehyde/surfactant ratio had effect significantly
(p<0.05) to mean droplet diameter, polidispersity index, ζ-potential, turbidity and whiteness index, while no significant
effect (p>0.05) to viscosity. The mean droplet diameter ranged from 50.48 to 106.4 nm, polydispersity index from 0.06 to
0.28 and ζ-potential from -4.11 to -6.98 mV. The smallest droplet size was produced using 5% cinnamaldehyde and 5%
Tween 80. Response surface for droplet diameter showed that the higher the cinnamaldehyde and surfactant concentrations,
the larger the droplet diameter, polydispersity index and whiteness index. However, the ζ-potential increased as the
cinnamaldehyde concentration decreased and Tween 80 increased. Increasing the cinnamaldehyde concentration led
to an increase in turbidity. Formulation of 5% cinnamaldehyde and 6.23% Tween 80 gave no observable separation of
the nanoemulsion with minimum droplet size, polidispersity index, viscosity, turbidity, whiteness index and maximum
ζ-potential in modulus. The stability of the optimum formulation was sustained for 10 days upon storage at 4°C. The
values of droplet diameter, PDI and ζ-potential were 55.50 nm, 0.08 and -5.38 mV, respectively.
A ZnO gas sensor was successfully prepared by RF sputtering. The maximum sensitivity of the sensor for vinegar test application was at 400oC. The ZnO based sensor showed good sensitivity for vinegar test in the concentration range of 4% to 9%. The work reveals the ability of using ZnO gas sensor to determine the acid concentrations of the vinegars for food requirements.
Three novel ruthenium(II) complexes of the general formula [Ru(II)(bpy)2
L]2+ were synthesized, where L =
1,10-phenanthroline derivatives of position 2 imidazole having 3,4-didecyloxy-phenyl (ddip), 3,4-ditetradecyloxy-phenyl
(dtip) and 3,4-dihexadecyloxy-phenyl (dhip). All complexes were characterized by elemental analysis, 1
H-NMR and ESI-MS.
Their photophysical properties have also been studied by UV-visible spectroscopy and fluorescence spectroscopy. The
complexes exhibit Ru(II) metal centered emission at approximately 610 nm in acetonitrile solution at room temperature. DNA
binding studies were carried out by UV-visible titration, luminescence titration and viscosity studies. The results indicated
that [Ru(bpy)2
(ddip)]2+ binds to CT-DNA by partial intercalation mode, while [Ru(bpy)2
(dtip)]2+ and [Ru(bpy)2
(dhip)]2+
bind intercalatively via extended ligands.
Second order linear two-point boundary value problems were solved using extended cubic B-spline interpolation method. Extended cubic B-spline is an extension of cubic B-spline consisting of one shape parameter, called λ. The resulting approximated analytical solution for the problems would be a function of λ. Optimization of λ was carried out to find the best value of λ that generates the closest fit to the differential equations in the problems. This method approximated the solutions for the problems much more accurately compared to finite difference, finite element, finite volume and cubic B-spline interpolation methods.
A high-order uniform Cartesian grid compact finite difference scheme for the Goursat problem is developed. The basic idea of high-order compact schemes is to find the compact approximations to the derivatives terms by differentiating centrally the governing equations. Our compact scheme will approximate the derivative terms by involving the higher terms and reducing the number of grid points. The compact finite difference scheme is given for general form of the Goursat problem in uniform domain and illustrates the performance by applying a linear problem. Numerical experiments have been conducted with the new scheme and encouraging results have been obtained. In this paper we present the compact finite difference scheme for the Goursat problem. With the aid of computational software the scheme was programmed for determining the relative errors of linear Goursat problem.
We study and discuss the effect of thermal slip on steady free convection flow of a viscous, incompressible micropolar fluid past a vertical moving plate in a saturated porous medium. The effect of viscous dissipation is incorporated in the energy equation. The associated partial differential equations are transformed into a system of ordinary differential equations using similarity transformations generated by a group method and this system is then solved numerically. The effect of controlling parameters on the dimensionless velocity, angular velocity and temperature as well as friction factor, couple stress factor and heat transfer rate are shown graphically and discussed in detail. It is found that the dimensional velocity and angular velocity decrease whilst the temperature increases with velocity slip parameter. It is further found that thermal slip decreases the dimensional velocity and temperature but increases the dimensional angular velocity. Data from published work and our results are found to be in good agreement.
A combined similarity-numerical solution of the magnetohydrodynamic boundary layer slip flow of an electrically conducting non-Newtonian power-law nanofluid along a heated radiating moving vertical plate is explored. Our nanofluid model incorporates the influences of the thermophoresis and the Brownian motion. The basic transport equations are made dimensionless first and then suitable similarity transformations are applied to reduce them into a set of nonlinear ordinary differential equations with the associated boundary conditions. The reduced equations are then solved numerically. Graphical results for the non-dimensional flow velocity, the temperature and the nanoparticles volume fraction profiles as well as for the friction factor, the local Nusselt and the Sherwood numbers are exhibited and examined for various values of the controlling parameters to display the interesting aspects of the solutions. It was found that the friction factor increases with the increase of the magnetic field (M), whilst it is decreased with the linear momentum slip parameter (a). The linear momentum slip parameter (a) reduces the heat transfer rates and the nanoparticles volume fraction rates. Our results are compatible with the existing results for a special case.
Four areas of Malaysia were selected for the study of filamentous micro fungi occupying soil habitats. Ampang, Kota Bharu, Bandar Melaka, and Kuantan were examined for micro-fungi species content and diversity of isolates. Species recovered from the soils of Malaysia, represent 63 genera and four classes, according to current concepts of fungal taxonomy (Clements and Shear, 1964; Domsch and Gams, 1980). Most isolates belonged to the imperfect fungal class Deuteromycetes, a few species represented the Zygomycetes, and only isolated incidents of Mastigomycetes and Ascomycetes were found occupying the soil of these regions.
Empat kawasan di Malaysia di pilih untuk penyelidikan pembiakan mikrofungi dipermukaan tanah. Kawasan-kawasan kajian yang mengandungi berbagai-bagai species mikro-fungi tersebut ialah Ampang, Kota Bharu, Bandar Melaka, dan Kuantan. Mengikut pengelasan konsep fungi (Clements dan Shear, 1964; Domish dan Gams, 1980) species mikro-fungi yang ditemui dipermukaan tanah Malaysia terdiri dari 63 "genera" dan empat kelas. Kebanyakannya terdiri dari kelas "Deuteromycetes", sebilangannya mewakili kelas "Zygomycetes", dan cuma sebilangan kecil sahaja terdiri dari kelas "Mastigomycetes" dan "Ascomycetes ".
The effects of prenatal caffeine exposure were examined on the morphological development and early development of reflexes in the mice pups, and further, the anxiety was also studied in the weaned mice using the plus-maze test. It was found that the postnatal body weight gain of the treated pups declined significantly. The normal eye-opening and hair appearance were also affected in the pups due to caffeine treatment. Measurement of early development of sensory motor reflexes in the pups showed that during the first week, caffeine had significantly stimulated the righting reflex, cliff avoidance and rotating reflexes with interaction between age and treatment doses. It was found in the plus-maze test that caffeine had significantly reduced the percentages of time spent as well as the entries into the open arms indicating for an anxiogenic action of caffeine in the young adult mouse. Also, caffeine stimulated the locomotor activity in the mouse as exemplified by an increase in the total number of arm entries in the plusÂmaze task. The present data support the basic conclusion that prenatal caffeine has a direct in utero action on the reflexes of the developing mouse pups and the anxiogenic action produced in them is longer lasting in nature.
Kajian ini menilai potensi ekstrak pewarna kaliks Hibiscus Sabdariffa L. (rosel) sebagai bahan sensor. Dalam kajian ini, sensor pH dibangunkan menggunakan ekstrak warna kemerahan semulajadi dalam kelopak rosel, delfinidin-3-sambubiosida yang dipegunkan dalam kertas turas gentian kaca. Dalam larutan bebas, ekstrak rosel dicirikan menggunakan spektrofotometer UL-nampak untuk mengkaji kesan pH, kepekatan ekstrak, masa ransangan keadaan mantap, analisis kebolehulangan dan analisis kestabilan foto. Ekstrak rosel terpegun dicirikan dengan menggunakan spektrofotometer pantulan untuk mengkaji kesan pH, masa ransangan keadaan mantap, analisis kebolehulangan, analisis kestabilan foto dan kajian histerisis. Hasil kajian menunjukkan bahawa ekstrak bahan semulajadi boleh digunakan sebagai bahan sensor dalam pembinaan sensor optik pH.
Kajian ini bertujuan untuk memetakan kes kemortalan bayi mengikut daerah di Semenanjung Malaysia bagi tahun 1991 hingga 2000. Penganggaran risiko relatif berdasarkan kaedah Bayes empirik telah digunakan dalam kajian ini. Tiga kaedah penganggaran parameter dihuraikan iaitu kaedah momen, kaedah kebolehjadian maksimum dan kaedah penganggaran gabungan momen dan kebolehjadian maksimum. Keteguhan anggaran parameter yang diperoleh diuji menggunakan kaedah Bootstrap. Hasil kajian mendapati jurang antara kawasan berisiko rendah dengan kawasan berisiko tinggi adalah lebih besar pada awal dekad 2000 berbanding pada awal dekad 1990-an walaupun pada dasarnya kadar mortaliti bayi secara keseluruhannya adalah semakin berkurangan pada peringkat nasional. Kawasan pantai timur Semenanjung Malaysia masih pada takuk yang sama iaitu masih berada dalam kategori berisiko tinggi sepanjang tempoh yang dikaji. Seterusnya, gambaran terdapatnya tompokan risiko juga turut terpapar dalam peta yang dihasilkan. Berdasarkan kaedah Bootstrap, parameter-parameter yang dianggarkan dalam kajian ini adalah teguh.
Time series analysis and forecasting has become a major tool in many applications in air pollution and environmental management fields. Among the most effective approaches for analyzing time series data is the model introduced by Box and Jenkins, ARIMA (Autoregressive Integrated Moving Average). In this study we used Box-Jenkins methodology to build ARIMA model for monthly ozone data taken from an Automatic Air Quality Monitoring System in Kemaman station for the period from 1996 to 2007 with a total of 144 readings. Parametric seasonally adjusted ARIMA (0,1,1) (1,1,2)12 model was successfully applied to predict the long-term trend of ozone concentration. The detection of a steady statistical significant upward trend for ozone concentration in Kemaman is quite alarming. This is likely due to sources of ozone precursors related to industrial activities from nearby areas and the increase in road traffic volume.