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  1. Dissolved nutrients and chlorophyll a status of the Setiu River, Terengganu, Malaysia
    Suhaimi S, Tahir NM, Suriyati S
    Bull Environ Contam Toxicol, 2004 Dec;73(6):1094-100.
    PMID: 15674725
  2. Does telephone lactation counselling improve breastfeeding practices? A randomised controlled trial
    Tahir NM, Al-Sadat N
    Int J Nurs Stud, 2013 Jan;50(1):16-25.
    PMID: 23084438 DOI: 10.1016/j.ijnurstu.2012.09.006
    Exclusive breastfeeding rates in Malaysia remains low despite the implementation of the Baby Friendly Hospital Initiative (BFHI) policy in government hospitals. It has been suggested that any form of postnatal lactation support will lead to an increase in exclusive breastfeeding rates.
  3. A preliminary study of total petrogenic hydrocarbon distribution in Setiu Wetland, southern South China Sea (Malaysia)
    Suratman S, Tahir NM, Latif MT
    Bull Environ Contam Toxicol, 2012 May;88(5):755-8.
    PMID: 22392007 DOI: 10.1007/s00128-012-0574-2
    The distribution of total petrogenic hydrocarbon was investigated in the subsurface water of Setiu Wetland from July to October 2008. The concentration was quantified by UV-fluorescence spectroscopy and ranged from 4 to 121 μg/L (mean 60 ± 41 μg/L). Higher total petrogenic hydrocarbon concentrations were found in area with high boating activities suggesting that the contribution is likely related to fossil fuel combustion. The present study also revealed that the total petrogenic hydrocarbon values are still lower that those reported in Malaysian coastal waters.
  4. Adsorption, desorption, and mobility of metsulfuron methyl in Malaysian agricultural soils
    Abdullah AR, Sinnakkannu S, Tahir NM
    Bull Environ Contam Toxicol, 2001 Jun;66(6):762-9.
    PMID: 11353379
  5. Hydrocarbons in seawater and sediment from the west coast of Peninsular Malaysia
    Abdullah AR, Tahir NM, Wei LK
    Bull Environ Contam Toxicol, 1994 Oct;53(4):618-26.
    PMID: 8000192
  6. Sandbar-regulated hydrodynamic influences on river hydrochemistry at Mengabang Telipot River, Peninsular Malaysia
    Koh MK, Sathiamurthy E, Suratman S, Tahir NM
    Environ Monit Assess, 2012 Dec;184(12):7653-64.
    PMID: 22302401
    Influences of river hydrodynamic behaviours on hydrochemistry (salinity, pH, dissolved oxygen saturations and dissolved phosphorus) were evaluated through high spatial and temporal resolution study of a sandbar-regulated coastal river. River hydrodynamic during sandbar-closed event was characterized by minor dependency on tidal fluctuations, very gradual increase of water level and continual low flow velocity. These hydrodynamic behaviours established a hydrochemistry equilibrium, in which water properties generally were characterized by virtual absence of horizontal gradients while vertical stratifications were significant. In addition, the river was in high trophic status as algae blooms were visible. Conversely, river hydrodynamic in sandbar-opened event was tidal-controlled and showed higher flow velocity. Horizontal gradients of water properties became significant while vertically more homogenised and with lower trophic status. In essence, this study reveals that estuarine sandbar directly regulates river hydrodynamic behaviours which in turn influences river hydrochemistry.
  7. On-line preconcentration and determination of trace metals using a flow injection system coupled to ion chromatography
    Bin Abas MR, Takruni IA, Abdullah Z, Tahir NM
    Talanta, 2002 Nov 12;58(5):883-90.
    PMID: 18968820
    A flow injection (FI) method with on-line preconcentration using a mini-column loaded with 8-hydroxyquinoline immobilized on controlled pore glass (CPG-8HQ) is described for the determination of trace metals by ion chromatography (IC) with pyridine-2-6-dicarboxylic acid (PDCA) as the eluent. Copper, cadmium, lead, zinc, nickel and iron were determined at ppb level after post-column derivatization with 4-(2-pyridylazo)-resorcinol (PAR). The detection limits (3sigma) for the FI/IC system were 8.27, 0.89, 0.09, 0.06, 0.09 and 0.07 g l(-1) for Pb(2+), Cd(2+), Cu(2+) Ni(2+), Zn(2+) and Fe(3+), respectively, using 5 ml sample volume. The method was applied to the analysis of Malaysian natural waters.
  8. Fluorescence studies of selected 2-alkylaminopyrimidines
    Abdullah Z, Tahir NM, Abas MR, Aiyub Z, Low BK
    Molecules, 2004 Jun 30;9(7):520-6.
    PMID: 18007451
    The reactions of 2-chloropyrimidine with methylamine, ethylamine and piperidine gave the corresponding 2-N-methylamino-, 2-N-ethylamino- and 2N- piperidinopyrimidines, respectively. The fluorescence properties of these alkylamino derivatives in chloroform, ethyl acetate, carbon tetrachloride, acetone, ether, ethanol and methanol were studied. All the alkylamino derivatives showed the highest fluorescence intensity in polar protic solvents; thus 2-N-methylaminopyrimidine (highest fluorescence intensity at 377 nm when excited at 282 nm) and 2-N-ethylaminopyrimidine (highest fluorescence intensity at 375 nm, when excited at 286 nm) showed the highest fluorescence in methanol. In ethanol, 2-N-piperidinopyrimidine showed a fluorescence peak at 403 nm when excited at 360 nm and in chloroform it fluoresced at 392 nm when excited at 356 nm.
  9. Distribution and sources of lipid compound series in sediment cores of the southern South China Sea
    Tahir NM, Pang SY, Simoneit BR
    Environ Sci Pollut Res Int, 2015 May;22(10):7557-68.
    PMID: 25752627 DOI: 10.1007/s11356-015-4184-5
    Three short sediment cores from inner continental shelf of the southern South China Sea (5-50 km) off Terengganu were analyzed for lipid contents (i.e., homologous aliphatic compounds and sterols) using gas chromatography-mass spectrometry. The concentrations of the total aliphatic hydrocarbons (TAHs) ranged from 0.152 to 6.91 μg/g dry weight. The n-alkane distribution was from nC₁₃ to nC₃₆, with a carbon preference index (CPI₁₃₋₃₅) from 1.08 to 4.28 and a carbon number maximum (Cmax), depending on a sample, at 31 or 18. In addition, a strong odd-to-even carbon number predominance was observed in nC₂₅-nC₃₅ range. The distribution of the n-alkanoic acids and n-alkanols in all samples exhibited an even-to-odd carbon number predominance and ranged from C₁₀ to C₂₆ and from C₁₂ to C₃₄, respectively. The n-alkanols were dominated by the long-chain homologs with Cmax at 22; on the other hand, the n-alkanoic acid distributions showed a predominance of short-chain homologs with a Cmax at 16. The total sterol concentrations ranged from 0.41 to 3.57 μg/g dry weight. Cholesterol was most abundant at the offshore stations, whereas sitosterol was dominant at near-shore station. Pentacyclic triterpenoids such as friedelin and taraxerol α- and β-amyrins, which are known biomarkers for higher plants, were detected at all stations with a dilution trend offshore. In conclusion, the marine sediments off southern Terengganu can still be considered uncontaminated, where the compound sources are biogenic from terrestrial plants superimposed with a marine productivity input.
  10. Classification of intelligence quotient via brainwave sub-band power ratio features and artificial neural network
    Jahidin AH, Megat Ali MS, Taib MN, Tahir NM, Yassin IM, Lias S
    Comput Methods Programs Biomed, 2014 Apr;114(1):50-9.
    PMID: 24560277 DOI: 10.1016/j.cmpb.2014.01.016
    This paper elaborates on the novel intelligence assessment method using the brainwave sub-band power ratio features. The study focuses only on the left hemisphere brainwave in its relaxed state. Distinct intelligence quotient groups have been established earlier from the score of the Raven Progressive Matrices. Sub-band power ratios are calculated from energy spectral density of theta, alpha and beta frequency bands. Synthetic data have been generated to increase dataset from 50 to 120. The features are used as input to the artificial neural network. Subsequently, the brain behaviour model has been developed using an artificial neural network that is trained with optimized learning rate, momentum constant and hidden nodes. Findings indicate that the distinct intelligence quotient groups can be classified from the brainwave sub-band power ratios with 100% training and 88.89% testing accuracies.
  11. Surfactants in the sea-surface microlayer and atmospheric aerosol around the southern region of Peninsular Malaysia
    Jaafar SA, Latif MT, Chian CW, Han WS, Wahid NB, Razak IS, et al.
    Mar Pollut Bull, 2014 Jul 15;84(1-2):35-43.
    PMID: 24930738 DOI: 10.1016/j.marpolbul.2014.05.047
    This study was conducted to determine the composition of surfactants in the sea-surface microlayer (SML) and atmospheric aerosol around the southern region of the Peninsular Malaysia. Surfactants in samples taken from the SML and atmospheric aerosol were determined using a colorimetric method, as either methylene blue active substances (MBAS) or disulphine blue active substances (DBAS). Principal component analysis with multiple linear regressions (PCA-MLR), using the anion and major element composition of the aerosol samples, was used to determine possible sources of surfactants in atmospheric aerosol. The results showed that the concentrations of surfactants in the SML and atmospheric aerosol were dominated by anionic surfactants and that surfactants in aerosol were not directly correlated (p>0.05) with surfactants in the SML. Further PCA-MLR from anion and major element concentrations showed that combustion of fossil fuel and sea spray were the major contributors to surfactants in aerosol in the study area.
  12. Distribution, sources and potential health risks of polycyclic aromatic hydrocarbons (PAHs) in PM2.5 collected during different monsoon seasons and haze episode in Kuala Lumpur
    Sulong NA, Latif MT, Sahani M, Khan MF, Fadzil MF, Tahir NM, et al.
    Chemosphere, 2019 Mar;219:1-14.
    PMID: 30528968 DOI: 10.1016/j.chemosphere.2018.11.195
    This study aimed to determine the distribution and potential health risks of polycyclic aromatic hydrocarbons (PAHs) in PM2.5 collected in Kuala Lumpur during different monsoon seasons. The potential sources of PM2.5 were investigated using 16 priority PAHs with additional of biomass tracers namely levoglucosan (LV), mannosan (MN) and galactosan (GL). This study also investigated the cytotoxic potential of the extracted PAHs towards V79-4 cells. A high-volume air sampler (HVS) was used to collect PM2.5 samples for 24 h. PAHs were extracted using dichloromethane (DCM) while biomass tracers were extracted by a mixture of DCM/methanol (3:1) before analysis with gas chromatography-mass spectrometry (GC-MS). The cytotoxicity of the PAHs extract was determined by assessing the cell viability through the reduction of tetrazolium salts (MTT). The results showed that the total mean ± SD concentrations of PAHs during the southwest (SW) and northeast (NE) monsoons were 2.51 ± 0.93 ng m-3 and 1.37 ± 0.09 ng m-3, respectively. Positive matrix factorization (PMF) using PAH and biomass tracer concentrations suggested four potential sources of PM2.5; gasoline emissions (29.1%), natural gas and coal burning (28.3%), biomass burning (22.3%), and diesel and heavy oil combustion (20.3%). Health risk assessment showed insignificant incremental lifetime cancer risk (ILCR) of 2.40E-07 for 70 years of exposure. MTT assay suggested that PAHs extracts collected during SW monsoon have cytotoxic effect towards V79-4 cell at the concentrations of 25 μg mL-1, 50 μg mL-1, 100 μg mL-1 whereas non-cytotoxic effect was observed on the PAHs sample collected during NE monsoon.
  13. Intraoperative blood loss and blood transfusion requirement among liver transplant recipients: A national single-center experience 2020
    Yusop MF, Tahir NM, Azim SMSS, Kamaruzaman AA, Hata NRM, Kugaan A, et al.
    Asian J Transfus Sci, 2023;17(2):251-255.
    PMID: 38274975 DOI: 10.4103/ajts.ajts_38_21
    BACKGROUND: Liver transplantation (LT) is a complicated surgical procedure with high risk for massive intraoperative blood loss due to pre-existing coagulopathy, portosystemic shunts with collateral circulations, and splenomegaly. The transfusion service will direct most of their resources toward LT programs with great impact on cost. The purpose of this study was to evaluate single center transfusion strategies and to identify the risk factors associated with the intraoperative blood loss and blood transfusion.

    METHODS: The study includes 18 patients who underwent LT at Hospital Selayang between January 2020 and December 2020. Retrospective analysis of data included preoperative assessment of coagulopathy, intraoperative blood loss, and blood component transfusion.

    RESULTS: The mean age in the study group was 36.4 ± 12.68 years. The mean intraoperative blood loss was 4450 ± 1646 ml requiring 4.17 ± 3.3 packed red blood cell (PRBC) units, 7.56 ± 5.5 platelet units, and 9.50 ± 6.0 fresh-frozen plasma units. The independent risk factor for high blood loss (HBL) group was lower preoperative platelet count and it is statistically significant (P = 0.024). The HBL group is associated with higher usage of PRBC (P = 0.024) and platelet units (P = 0.031) and it is statistically significant. The length of stay (LOS) in intensive care unit (ICU) averaging 8.6 ± 4.95 days, and there is no significant differences comparing the HBL and LBL group (P = 0.552). The mortality <90 days for all recipients was 22.2%.

    CONCLUSION: The preoperative platelet count for is the most important factor associated with HBL in LT procedure. The usage of PRBC and platelet units was statistically higher in the HBL group. Comparing HBL and LBL patients, there is no difference in terms of the LOS in ICU postoperatively. A larger sample size would be needed in view of relatively small sample size.

  14. BTEX compositions and its potential health impacts in Malaysia
    Latif MT, Abd Hamid HH, Ahamad F, Khan MF, Mohd Nadzir MS, Othman M, et al.
    Chemosphere, 2019 Dec;237:124451.
    PMID: 31394440 DOI: 10.1016/j.chemosphere.2019.124451
    This study aims to determine the composition of BTEX (benzene, toluene, ethylbenzene and xylene) and assess the risk to health at different sites in Malaysia. Continuous monitoring of BTEX in Kuala Lumpur City Centre, Kuala Terengganu, Kota Kinabalu and Fraser Hill were conducted using Online Gas Chromatograph. For comparison, BTEX at selected hotspot locations were determined by active sampling method using sorbent tubes and Thermal Desorption Gas Chromatography Mass Spectrometry. The hazard quotient (HQ) for non-carcinogenic and the life-time cancer risk (LTCR) of BTEX were calculated using the United States Environmental Protection Agency (USEPA) health risk assessment (HRA) methods. The results showed that the highest total BTEX concentrations using continuous monitoring were recorded in the Kuala Lumpur City Centre (49.56 ± 23.71 μg/m3). Toluene was the most dominant among the BTEX compounds. The average concentrations of benzene ranged from 0.69 ± 0.45 μg/m3 to 6.20 ± 3.51 μg/m3. Measurements using active sampling showed that BTEX concentrations dominated at the roadside (193.11 ± 114.57 μg/m3) in comparison to petrol station (73.08 ± 30.41 μg/m3), petrochemical industry (32.10 ± 13.13 μg/m3) and airport (25.30 ± 6.17 μg/m3). Strong correlations among BTEX compounds (p<0.01, r>0.7) at Kuala Lumpur City Centre showed that BTEX compounds originated from similar sources. The values of HQ at all stations were <1 indicating the non-carcinogenic risk are negligible and do not pose threats to human health. The LTCR value based on benzene inhalation (1.59 × 10-5) at Kuala Lumpur City Centre were between 1 × 10-4 and 1 × 10-5, representing a probable carcinogenic risk.
  15. Physicochemical factors and their potential sources inferred from long-term rainfall measurements at an urban and a remote rural site in tropical areas
    Khan MF, Maulud KNA, Latif MT, Chung JX, Amil N, Alias A, et al.
    Sci Total Environ, 2018 Feb 01;613-614:1401-1416.
    PMID: 29898507 DOI: 10.1016/j.scitotenv.2017.08.025
    Air pollution can be detected through rainwater composition. In this study, long-term measurements (2000-2014) of wet deposition were made to evaluate the physicochemical interaction and the potential sources of pollution due to changes of land use. The rainwater samples were obtained from an urban site in Kuala Lumpur and a highland-rural site in the middle of Peninsular Malaysia. The compositions of rainwater were obtained from the Malaysian Meteorological Department. The results showed that the urban site experienced more acidity in rainwater (avg=277mm, range of 13.8 to 841mm; pH=4.37) than the rural background site (avg=245mm, range of 2.90 to 598mm; pH=4.97) due to higher anthropogenic input of acid precursors. The enrichment factor (EF) analysis showed that at both sites, SO42-, Ca2+ and K+ were less sensitive to seawater but were greatly influenced by soil dust. NH4+ and Ca2+ can neutralise a larger fraction of the available acid ions in the rainwater at the urban and rural background sites. However, acidifying potential was dominant at urban site compared to rural site. Source-receptor relationship via positive matrix factorisation (PMF 5.0) revealed four similar major sources at both sites with a large variation of the contribution proportions. For urban, the major sources influence on the rainwater chemistry were in the order of secondary nitrates and sulfates>ammonium-rich/agricultural farming>soil components>marine sea salt and biomass burning, while at the background site the order was secondary nitrates and sulfates>marine sea salt and biomass burning=soil components>ammonia-rich/agricultural farming. The long-term trend showed that anthropogenic activities and land use changes have greatly altered the rainwater compositions in the urban environment while the seasonality strongly affected the contribution of sources in the background environment.
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