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  1. Fulltext NIR spectroscopic properties of aqueous acids solutions
    Omar AF, Atan H, Matjafri MZ
    Molecules, 2012 Jun 15;17(6):7440-50.
    PMID: 22706373 DOI: 10.3390/molecules17067440
    Acid content is one of the important quality attributes in determining the maturity index of agricultural product, particularly fruits. Despite the fact that much research on the measurement of acidity in fruits through non-destructive spectroscopy analysis at NIR wavelengths between 700 to 1,000 nm has been conducted, the same response towards individual acids is not well known. This paper presents NIR spectroscopy analysis on aqueous citric, tartaric, malic and oxalic solutions through quantitative analysis by selecting a set of wavelengths that can best be used to measure the pH of the solutions. The aquaphotomics study of the acid solutions has generated R² above 0.9 for the measurement of all acids. The most important wavelengths for pH are located at 918-925 nm and 990-996 nm, while at 975 nm for water.
  2. Fulltext Reliability and construct validity of the Bahasa Malaysia version of transtheoretical model (TTM) questionnaire for smoking cessation and relapse among Malaysian adult
    Yasin SM, Taib KM, Zaki RA
    Asian Pac J Cancer Prev, 2011;12(6):1439-43.
    PMID: 22126478
    The transtheoretical model (TTM) has been used as one of the major constructs in developing effective cognitive behavioural interventions for smoking cessation and relapse prevention, in Western societies. This study aimed to examine the reliability and construct validity of the translated Bahasa Malaysia version of TTM questionnaire among adult smokers in Klang Valley, Malaysia. The sample consisted of 40 smokers from four different worksites in Klang Valley. A 26-item TTM questionnaire was administered, and a similar set one week later. The questionnaire consisted of three measures; decisional balance, temptations and impact of smoking. Construct validity was measured by factor analysis and the reliability by Cronbach' s alpha (internal consistency) and test-retest correlation. Results revealed that Cronbach' s alpha coefficients for the items were: decisional balance (0.84; 0.74) and temptations (0.89; 0.54; 0.85). The values for test retest correlation were all above 0.4. In addition, factor analysis suggested two meaningful common factors for decisional balance and three for temptations. This is consistent with the original construct of the TTM questionnaire. Overall results demonstrated that construct validity and reliability were acceptable for all items. In conclusion, the Bahasa Malaysia version of TTM questionnaire is a reliable and valid tool in ass.
  3. Quantitative ultrasound measurement of the calcaneus in Southeast Asian children with thalassemia: comparison with dual-energy X-ray absorptiometry
    Sani FM, Sarji SA, Bilgen M
    J Ultrasound Med, 2011 Jul;30(7):883-94.
    PMID: 21705720
    OBJECTIVES: The purpose of this study was to test the hypothesis that quantitative ultrasound properties of the calcaneus in Southeast Asian children treated for thalassemia have different characteristics than those of their healthy counterparts and thereby can be used for assessing the risk of osteoporosis.

    METHODS: Broadband ultrasound attenuation and the speed of sound were measured from groups of thalassemic and healthy children and compared with bone mineral density (BMD) estimated from dual-energy X-ray absorptiometry to determine intergroup and intragroup dependencies of the measurements and variations with differences in sex and anthropometric characteristics.

    RESULTS: Broadband ultrasound attenuation and speed of sound measurements were found to be independent of sex but dependent on age in the thalassemic children. Consistently, broadband ultrasound attenuation had lower values and the speed of sound had higher values compared with those of the healthy children in each age group. Broadband ultrasound attenuation correlated well with the speed of sound and also with age, weight, and height, but the speed of sound did not show an association with these parameters. Broadband ultrasound attenuation correlated moderately with BMD in the lumbar spine and whole body, but the corresponding association was much weaker for the speed of sound. In the thalassemic children, both broadband ultrasound attenuation and BMD increased with age as they grew older but not fast enough compared with the healthy children, and the risk of osteoporosis was greater at older ages.

    CONCLUSIONS: Calcaneal quantitative ultrasound may be used as a diagnostic screening tool for assessing the bone status in thalassemic Southeast Asian children and for deciding whether further dual-energy X-ray absorptiometry is needed, particularly in those who are at a greater risk for osteoporosis as identified by low body weight and height.

  4. Self-efficacy and self-care behavior of Malaysian patients with type 2 diabetes: a cross sectional survey
    Sharoni SK, Wu SF
    Nurs Health Sci, 2012 Mar;14(1):38-45.
    PMID: 22288688 DOI: 10.1111/j.1442-2018.2011.00658.x
    This study investigated the association between self-efficacy and self-care behavior to determine the degree of self-efficacy and to examine differences in self-efficacy according to patient variables, including state of health, of Malaysian patients with type 2 diabetes. The sample comprised 388 patients (respondents). We collected the data from December 2010 to February 2011. We found a significant positive relationship between self-efficacy and self-care behavior (r(s) = 0.481, P < 0.001). The degree of self-efficacy was moderately high (mean = 7.570). We found significant differences between self-efficacy and education level (Wilk's Lambda = 0.918, F[12, 1008] = 2.779, P < 0.05), duration of diabetes (Wilk's Lambda = 0.954, F[8, 736] = 2.264, P < 0.05), other chronic conditions (Wilk's Lambda = 0.967, F[4, 383] = 3.304, P < 0.05) and diabetic complications (Wilk's Lambda = 0.963, F[4, 383] = 3.653, P < 0.05). Self-efficacy can be used as a model to understand self-care behavior. Individualized nursing interventions based on self-efficacy theory should be utilized in high risk diabetic patients so as to assist and improve self-care behavior.
    Study site: Diabetic clinic and the medical, nephrology, orthopedic, and surgery wards, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
  5. Fulltext Simultaneous determination of secondary metabolites from Vinca rosea plant extractives by reverse phase high performance liquid chromatography
    Siddiqui MJ, Ismail Z, Saidan NH
    Pharmacogn Mag, 2011 Apr;7(26):92-6.
    PMID: 21716929 DOI: 10.4103/0973-1296.80662
    Vinca rosea (Apocynaceae) is one of the most important and high value medicinal plants known for its anticancer alkaloids. It is the iota of the isolated secondary metabolites used in chemotherapy to treat diverse cancers. Several high performance liquid chromatography (HPLC) methods have been developed to quantify the active alkaloids in the plant. However, this method may serve the purpose in quantification of V. rosea plant extracts in totality.
  6. Utilization of greenhouse gases through dry reforming: screening of nickel-based bimetallic catalysts and kinetic studies
    Fan MS, Abdullah AZ, Bhatia S
    ChemSusChem, 2011 Nov 18;4(11):1643-53.
    PMID: 22191096
    A series of bimetallic catalysts containing nickel supported over MgO-ZrO2 were tested for activity in the dry reforming of carbon dioxide. A nickel-cobalt bimetallic catalyst gave the best performance in terms of conversion and coke resistance from a range of Ni-X bimetallic catalysts, X=Ca, K, Ba, La, and Ce. The nitrogen-adsorption and hydrogen-chemisorption studies showed the Ni-Co bimetallic supported catalyst to have good surface area with high metal dispersion. This contributed to the high catalytic activity, in terms of conversion activity and stability of the catalyst, at an equimolar methane/carbon dioxide feed ratio. The kinetics of methane dry reforming are studied in a fixed-bed reactor over an Ni-Co bimetallic catalyst in the temperature range 700-800 °C by varying the partial pressures of CH4 and CO2. The experimental data were analyzed based on the proposed reaction mechanism using the Langmuir-Hinshelwood kinetic model. The activation energies for methane and carbon dioxide consumption were estimated at 52.9 and 48.1 kJ mol(-1), respectively. The lower value of CO2 activation energy compared to the activation energy of CH4 indicated a higher reaction rate of CO2, which owes to the strong basicity of nanocrystalline support, MgO-ZrO2.
  7. Population ecology and movement of the American cockroach (Dictyoptera: Blattidae) in sewers
    Tee HS, Saad AR, Lee CY
    J Med Entomol, 2011 Jul;48(4):797-805.
    PMID: 21845938
    The population size, age-class structure, and movement of the American cockroach, Periplaneta americana (L.) (Dictyoptera: Blattidae), were studied in three sewers in Penang, Malaysia, from September 2008 to October 2009. Eighteen to 20 glass-jar traps (two per manhole) were deployed for a 24-h period during each sampling occasion at each sewer. Adults and nymphs were active throughout the study period, with an average monthly trap catch of 57-97 adults and 79-99 nymphs. The mean proportions of adults and nymphs at the three sewers ranged from 0.47 to 0.57. Of the 2177 male and 2717 female cockroaches marked and released over the three sewers, recapture rates were 29.4-45.8 and 30.8-47.0%, respectively. The proportion of marked males and females did not differ significantly from the proportion of recaptured marked males and females. However, the mean number of times a marked female was recaptured was significantly greater than that of males. Of the 783 males and 1,030 females that were marked and recaptured, 19.4 and 24.7%, respectively, had moved between manholes, and significantly more females than males moved between manholes. Of the 406 recaptured marked adults that moved between manholes, 90.4% moved a distance of 2-20 m from their initial release site; one male moved 192 m, the longest distance recorded. Trap catch on each sampling occasion was positively correlated with daily mean temperature. The number of cockroach movements between manholes also was correlated with the mean daily minimum temperature.
  8. Fulltext Determination of ammonium ion using a reagentless amperometric biosensor based on immobilized alanine dehydrogenase
    Tan LL, Musa A, Lee YH
    Sensors (Basel), 2011;11(10):9344-60.
    PMID: 22163699 DOI: 10.3390/s111009344
    The use of the enzyme alanine dehydrogenase (AlaDH) for the determination of ammonium ion (NH(4)(+)) usually requires the addition of pyruvate substrate and reduced nicotinamide adenine dinucleotide (NADH) simultaneously to effect the reaction. This addition of reagents is inconvenient when an enzyme biosensor based on AlaDH is used. To resolve the problem, a novel reagentless amperometric biosensor using a stacked methacrylic membrane system coated onto a screen-printed carbon paste electrode (SPE) for NH(4)(+) ion determination is described. A mixture of pyruvate and NADH was immobilized in low molecular weight poly(2-hydroxyethyl methacrylate) (pHEMA) membrane, which was then deposited over a photocured pHEMA membrane (photoHEMA) containing alanine dehydrogenase (AlaDH) enzyme. Due to the enzymatic reaction of AlaDH and the pyruvate substrate, NH(4)(+) was consumed in the process and thus the signal from the electrocatalytic oxidation of NADH at an applied potential of +0.55 V was proportional to the NH(4)(+) ion concentration under optimal conditions. The stacked methacrylate membranes responded rapidly and linearly to changes in NH(4)(+) ion concentrations between 10-100 mM, with a detection limit of 0.18 mM NH(4)(+) ion. The reproducibility of the amperometrical NH(4)(+) biosensor yielded low relative standard deviations between 1.4-4.9%. The stacked membrane biosensor has been successfully applied to the determination of NH(4)(+) ion in spiked river water samples without pretreatment. A good correlation was found between the analytical results for NH(4)(+) obtained from the biosensor and the Nessler spectrophotometric method.
  9. Fulltext Chest imaging features of patients afflicted with Influenza A (H1N1) in a Malaysian tertiary referral centre
    Bux S, Mohd Ramli N, Ahmad Sarji S, Kamarulzaman A
    Biomed Imaging Interv J, 2010 Oct-Dec;6(4):e35.
    PMID: 21611071 MyJurnal DOI: 10.2349/biij.6.4.e35
    This is a retrospective descriptive study of the chest imaging findings of 118 patients with confirmed A(H1N1) in a tertiary referral centre. About 42% of the patients had positive initial chest radiographic (CXR) findings. The common findings were bi-basal air-space opacities and perihilar reticular and alveolar infiltrates. In select cases, high-resolution computed tomography (CT) imaging showed ground-glass change with some widespread reticular changes and atelectasis.
  10. Fulltext Visceral leishmaniasis (kala-azar) and malaria coinfection in an immigrant in the state of Terengganu, Malaysia: A case report
    Ab Rahman AK, Abdullah FH
    J Microbiol Immunol Infect, 2011 Feb;44(1):72-6.
    PMID: 21531357 DOI: 10.1016/j.jmii.2011.01.014
    Malaria is endemic in Malaysia. Leishmaniasis is a protozoan infection rarely reported in Malaysia. Here, a 24-year-old Nepalese man who presented with prolonged fever and hepatosplenomegaly is reported. Blood film examination confirmed a Plasmodium vivax malaria infection. Despite being adequately treated for malaria, his fever persisted. Bone marrow examination showed presence of Leishman-Donovan complex. He was successfully treated with prolonged course of amphotericin B. The case highlights the importance of awareness among the treating physicians of this disease occurring in a foreign national from an endemic region when he presents with fever and hepatosplenomegaly. Coinfection with malaria can occur although it is rare. It can cause significant delay of the diagnosis of leishmaniasis.
  11. Fulltext Two-stage surgery for a large cervical dumbbell tumour in neurofibromatosis 1: a case report
    Mohd Ariff S, Joehaimey J, Ahmad Sabri O, Abdul Halim Y
    Malays Orthop J, 2011 Nov;5(3):24-7.
    PMID: 25279032 MyJurnal DOI: 10.5704/MOJ.1111.003
    Spinal neurofibromas occur sporadically and typically occur in association with neurofibromatosis 1. Patients afflicted with neurofibromatosis 1 usually present with involvement of several nerve roots. This report describes the case of a 14- year-old child with a large intraspinal, but extradural tumour with paraspinal extension, dumbbell neurofibroma of the cervical region extending from the C2 to C4 vertebrae. The lesions were readily detected by MR imaging and were successfully resected in a two-stage surgery. The time interval between the first and second surgery was one month. We provide a brief review of the literature regarding various surgical approaches, emphasising the utility of anterior and posterior approaches.
  12. Empirical analysis of gross vehicle weight and free flow speed and consideration on its relation with differential speed limit
    Saifizul AA, Yamanaka H, Karim MR
    Accid Anal Prev, 2011 May;43(3):1068-73.
    PMID: 21376903 DOI: 10.1016/j.aap.2010.12.013
    Most highly motorized countries in the world have implemented different speed limits for light weight and heavy weight vehicles. The heavy vehicle speed limit is usually chosen to be lower than that of passenger cars due to the difficulty for the drivers to safely maneuver the heavy vehicle at high speed and greater impact during a crash. However, in many cases, the speed limit for heavy vehicle is set by only considering the vehicle size or category, mostly due to simplicity in enforcement. In this study, traffic and vehicular data for all vehicle types were collected using a weigh-in-motion system installed at Federal Route 54 in Malaysia. The first finding from the data showed that the weight variation for each vehicle category is considerable. Therefore, the effect of gross vehicle weight (GVW) and category of heavy vehicle on free flow speed and their interaction were analyzed using statistical techniques. Empirical analysis results showed that statistically for each type of heavy vehicle, there was a significant relationship between free flow speed of a heavy vehicle and GVW. Specifically, the results suggest that the mean and variance of free flow speed decrease with an increase GVW by the amount unrelated to size and shape for all GVW range. Then, based on the 85th percentile principle, the study proposed a new concept for setting the speed limit for heavy vehicle by incorporating GVW where a different speed limit is imposed to the heavy vehicle, not only based on vehicle classification, but also according to its GVW.
  13. Effect of autohydrolysis and enzymatic treatment on oil palm (Elaeis guineensis Jacq.) frond fibres for xylose and xylooligosaccharides production
    Sabiha-Hanim S, Noor MA, Rosma A
    Bioresour Technol, 2011 Jan;102(2):1234-9.
    PMID: 20797853 DOI: 10.1016/j.biortech.2010.08.017
    Oil palm (Elaeis guineensis Jacq.) is one of the most important commercial crops for the production of palm oil, which generates 10.88 tons of oil palm fronds per hectare of plantation as a by-product. In this study, oil palm frond fibres were subjected to an autohydrolysis treatment using an autoclave, operated at 121 °C for 20-80 min, to facilitate the separation of hemicelluloses. The hemicellulose-rich solution (autohydrolysate) was subjected to further hydrolysis with 4-16 U of mixed Trichoderma viride endo-(1,4)-β-xylanases (EC 3.2.1.8) per 100 mg of autohydrolysate. Autoclaving of palm fronds at 121°C for 60 min (a severity factor of 2.40) recovered 75% of the solid residue, containing 57.9% cellulose and 18% Klason lignin, and an autohydrolysate containing 14.94% hemicellulose, with a fractionation efficiency of 49.20%. Subsequent enzymatic hydrolysis of the autohydrolysate with 8 U of endoxylanase at 40 °C for 24 h produced a solution containing 17.5% xylooligosaccharides and 25.6% xylose. The results clearly indicate the potential utilization of oil palm frond, an abundantly available lignocellulosic biomass for the production of xylose and xylooligosaccharides which can serve as functional food ingredients.
  14. Fulltext Management of severe subglottic stenosis secondary to trauma: case to case comparison of resection anastomosis versus cartilage augmentation
    Asha'ari ZA, Islah W, Ahmad R, Suzina SA
    Med J Malaysia, 2010 Jun;65(2):157-9.
    PMID: 23756806 MyJurnal
    We studied two similar cases of severe subglottic stenosis secondary to trauma with different treatment modalities. One had laryngotracheal reconstruction with cartilage augmentation and the other had laryngotracheal resection anastomosis. We wish to compare the two popular choices of surgery for laryngotracheal stenosis from two cases with similar nature and severity thus highlighting the complexity of managing severe subglottic stenosis in adult.
  15. Study on the removal of pesticide in agricultural run off by granular activated carbon
    Jusoh A, Hartini WJ, Ali N, Endut A
    Bioresour Technol, 2011 May;102(9):5312-8.
    PMID: 21232934 DOI: 10.1016/j.biortech.2010.12.074
    In this batch study, the adsorption of malathion by using granular activated carbon with different parameters due to the particle size, dosage of carbons, as well as the initial concentration of malathion was investigated. Batch tests were carried out to determine the potential and the effectiveness of granular activated carbon (GAC) in removal of pesticide in agricultural run off. The granular activated carbon; coconut shell and palm shells were used and analyzed as the adsorbent material. The Langmuir and Freundlich adsorption isotherms models were applied to describe the characteristics of adsorption behavior. Equilibrium data fitted well with the Langmuir model and Freundlich model with maximum adsorption capacity of 909.1mg/g. The results indicate that the GAC could be used to effectively adsorb pesticide (malathion) from agricultural runoff.
  16. Single-trial subspace-based approach for VEP extraction
    Kamel N, Yusoff MZ, Hani AF
    IEEE Trans Biomed Eng, 2011 May;58(5):1383-93.
    PMID: 21177154 DOI: 10.1109/TBME.2010.2101073
    A signal subspace approach for extracting visual evoked potentials (VEPs) from the background electroencephalogram (EEG) colored noise without the need for a prewhitening stage is proposed. Linear estimation of the clean signal is performed by minimizing signal distortion while maintaining the residual noise energy below some given threshold. The generalized eigendecomposition of the covariance matrices of a VEP signal and brain background EEG noise is used to transform them jointly to diagonal matrices. The generalized subspace is then decomposed into signal subspace and noise subspace. Enhancement is performed by nulling the components in the noise subspace and retaining the components in the signal subspace. The performance of the proposed algorithm is tested with simulated and real data, and compared with the recently proposed signal subspace techniques. With the simulated data, the algorithms are used to estimate the latencies of P(100), P(200), and P(300) of VEP signals corrupted by additive colored noise at different values of SNR. With the real data, the VEP signals are collected at Selayang Hospital, Kuala Lumpur, Malaysia, and the capability of the proposed algorithm in detecting the latency of P(100) is obtained and compared with other subspace techniques. The ensemble averaging technique is used as a baseline for this comparison. The results indicated significant improvement by the proposed technique in terms of better accuracy and less failure rate.
  17. Experiences from a medical students' well-being workshop
    Yusoff MS, Rahim AF
    Med Educ, 2009 Nov;43(11):1108-9.
    PMID: 19874520 DOI: 10.1111/j.1365-2923.2009.03474.x
  18. Characteristics of supported nano-TiO2/ZSM-5/silica gel (SNTZS): photocatalytic degradation of phenol
    Zainudin NF, Abdullah AZ, Mohamed AR
    J Hazard Mater, 2010 Feb 15;174(1-3):299-306.
    PMID: 19818556 DOI: 10.1016/j.jhazmat.2009.09.051
    Photocatalytic degradation of phenol was investigated using the supported nano-TiO(2)/ZSM-5/silica gel (SNTZS) as a photocatalyst in a batch reactor. The prepared photocatalyst was characterized using XRD, TEM, FT-IR and BET surface area analysis. The synthesized photocatalyst composition was developed using nano-TiO(2) as the photoactive component and zeolite (ZSM-5) as the adsorbents, all supported on silica gel using colloidal silica gel binder. The optimum formulation of SNTZS catalyst was observed to be (nano-TiO(2):ZSM-5:silica gel:colloidal silica gel=1:0.6:0.6:1) which giving about 90% degradation of 50mg/L phenol solution in 180 min. The SNTZS exhibited higher photocatalytic activity than that of the commercial Degussa P25 which only gave 67% degradation. Its high photocatalytic activity was due to its large specific surface area (275.7 m(2)/g), small particle size (8.1 nm), high crystalline quality of the synthesized catalyst and low electron-hole pairs recombination rate as ZSM-5 adsorbent was used. The SNTZS photocatalyst synthesized in this study also has been proven to have an excellent adhesion and reusability.
  19. Scavenging behaviour of meranti sawdust in the removal of methylene blue from aqueous solution
    Ahmad A, Rafatullah M, Sulaiman O, Ibrahim MH, Hashim R
    J Hazard Mater, 2009 Oct 15;170(1):357-65.
    PMID: 19464117 DOI: 10.1016/j.jhazmat.2009.04.087
    Meranti (Philippine mahogany) sawdust, an inexpensive material, showed strong scavenging behaviour through adsorption for the removal of methylene blue (MB) from aqueous solution. Batch studies were performed to evaluate and optimize the effects of various parameters such as contact time, pH, initial dye concentrations and adsorbent dosage. Langmuir, Freundlich and Temkin isotherms were used to analyze the equilibrium data at different temperatures. The experimental data fitted well with the Langmuir adsorption isotherm, indicating thereby the mono layer adsorption of the dye. The monolayer sorption capacity of meranti sawdust for MB was found to be 120.48, 117.64, 149.25 and 158.73 mg/g at 30, 40, 50 and 60 degrees C, respectively. Thermodynamic calculations showed that the MB adsorption process is endothermic and spontaneous in nature. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model. The results indicated that the meranti sawdust could be an alternative material in place of more costly adsorbents used for dye removal.
  20. Isolation and characterization of oil palm constitutive promoter derived from ubiquitin extension protein (uep1) gene
    Masura SS, Parveez GK, Ismail I
    N Biotechnol, 2010 Sep 30;27(4):289-99.
    PMID: 20123048 DOI: 10.1016/j.nbt.2010.01.337
    The ubiquitin extension protein (uep1) gene was identified as a constitutively expressed gene in oil palm. We have isolated and characterized the 5' region of the oil palm uep1 gene, which contains an 828 bp sequence upstream of the uep1 translational start site. Construction of a pUEP1 transformation vector, which contains gusA reporter gene under the control of uep1 promoter, was carried out for functional analysis of the promoter through transient expression studies. It was found that the 5' region of uep1 functions as a constitutive promoter in oil palm and could drive GUS expression in all tissues tested, including embryogenic calli, embryoid, immature embryo, young leaflet from mature palm, green leaf, mesocarp and meristematic tissues (shoot tip). This promoter could also be used in dicot systems as it was demonstrated to be capable of driving gusA gene expression in tobacco.
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