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  1. Analysis and optimization of flocculation activity and turbidity reduction in kaolin suspension using pectin as a biopolymer flocculant
    Ho YC, Norli I, Alkarkhi AF, Morad N
    Water Sci Technol, 2009;60(3):771-81.
    PMID: 19657173 DOI: 10.2166/wst.2009.303
    The performance of pectin in turbidity reduction and the optimum condition were determined using Response Surface Methodology (RSM). The effect of pH, cation's concentration, and pectin's dosage on flocculating activity and turbidity reduction was investigated at three levels and optimized by using Box-Behnken Design (BBD). Coagulation and flocculation process were assessed with a standard jar test procedure with rapid and slow mixing of a kaolin suspension (aluminium silicate), at 150 rpm and 30 rpm, respectively, in which a cation e.g. Al(3+), acts as coagulant, and pectin acts as the flocculant. In this research, all factors exhibited significant effect on flocculating activity and turbidity reduction. The experimental data and model predictions well agreed. From the 3D response surface graph, maximum flocculating activity and turbidity reduction are in the region of pH greater than 3, cation concentration greater than 0.5 mM, and pectin dosage greater than 20 mg/L, using synthetic turbid wastewater within the range. The flocculating activity for pectin and turbidity reduction in wastewater is at 99%.
    Matched MeSH terms: Water Purification/methods*
  2. Study of evaluation of groundwater in Gadilam basin using hydrogeochemical and isotope data
    Prasanna MV, Chidambaram S, Shahul Hameed A, Srinivasamoorthy K
    Environ Monit Assess, 2010 Sep;168(1-4):63-90.
    PMID: 19609693 DOI: 10.1007/s10661-009-1092-5
    Gadilam river basin has gained its importance due to the presence of Neyveli Lignite open cast mines and other industrial complexes. It is also due to extensive depressurization of Cuddalore aquifer, and bore wells for New Veeranam Scheme are constructed downstream of the basin. Geochemical indicators of groundwater were used to identify the chemical processes that control hydrogeochemistry. Chemical parameters of groundwater such as pH, electrical conductivity, total dissolved solids, sodium (Na(+)), potassium (K(+)), calcium (Ca(+)), magnesium (Mg(+)), bicarbonate (HCO(-)(3)), sulfate (SO(-)(4)), phosphate (PO(-)(4)), and silica (H(4)SiO(4)) were determined. Interpretation of hydrogeochemical data suggests that leaching of ions followed by weathering and anthropogenic impact controls the chemistry of the groundwater. Isotopic study reveals that recharge from meteoric source in sedimentary terrain and rock-water interaction with significant evaporation prevails in hard rock region.
    Matched MeSH terms: Environmental Monitoring/methods*
  3. Simultaneous determination of ofloxacin and ornidazole in pharmaceutical preparations by capillary zone electrophoresis
    See KL, Elbashir AA, Saad B, Ali AS, Aboul-Enein HY
    Biomed Chromatogr, 2009 Dec;23(12):1283-90.
    PMID: 19488980 DOI: 10.1002/bmc.1251
    A simple, rapid and validated capillary electrophoretic method has been developed for the separation and determination of ofloxacin and ornidazole in pharmaceutical formulations with detection at 230 nm. Optimal conditions for the quantitative separations were investigated. Analysis times shorter than 4 min were obtained using a background electrolyte solution consisting of 25 mmol/L phosphoric acid adjusted with 1 M Tris buffer to pH 8.5, with hydrodynamic injection of 5 s and 20 kV separation voltage. The validation criteria for accuracy, precision, linearity and limits of detection and quantitation were examined and discussed. An excellent linearity was obtained in concentration range 25-250 microg/mL. The detection limits for ofloxacin and ornidazole were 1.03 +/- 0.11 and 1.80 +/- 0.06 microg/mL, respectively. The proposed method has been applied for the analysis of ofloxacin and ornidazole both individually and in a combined dosage tablet formulation. The proposed validated method showed recoveries between 96.16 and 105.23% of the nominal contents.
    Matched MeSH terms: Electrophoresis, Capillary/methods*
  4. Locally advanced anourological verrucous carcinoma: a multidisciplinary approach
    Koh PS, Roslani AC, Leow M, Ng CL, Lee GE
    Tech Coloproctol, 2009 Mar;13(1):101.
    PMID: 19288239 DOI: 10.1007/s10151-009-0464-8
    Matched MeSH terms: Urologic Surgical Procedures, Male/methods*
  5. Quantitative determination of propranolol by ultraviolet HPLC in human plasma
    Salman SA, Sulaiman SA, Ismail Z, Gan SH
    Toxicol. Mech. Methods, 2010 Mar;20(3):137-42.
    PMID: 20128736 DOI: 10.3109/15376511003602112
    Many previous published methods for the quantitative determination of propranolol (PRN) in human plasma have poor recoveries and were not validated according to the FDA guideline. The aim of this study is to develop a simple HPLC method for detecting PRN in human plasma and to validate it so that it can be applied to a clinical study. Chromatographic separation was achieved using a mixture of a mobile phase consisting of 160 ml water, 180 ml methanol, 70 ml acetonitrile, 2.5 ml acetic acid, and 125 microl triethylamine (v/v). The pH of the whole mixture was adjusted to 3.4. A flow rate of 0.5 ml/min was employed throughout with a 15 microl injection volume. Detection was done using a UV detector at 291 nm. The validated method was linear for concentrations ranging from 15-180 ng/ ml with a good separation and specificity for both PRN and its internal standard, oxprenolol (OXP), with excellent recoveries, precision, and accuracies. The limit of detection (LOD) and limit of quantification (LOQ) were 1 and 10 ng/ml, respectively. The stability studies demonstrated that PRN is stable in the autosampler vials and also up to 3.5 months. To the authors' knowledge, the recovery, that ranged between 97.9-102.7%, is the highest among all previously reported methods that used HPLC with UV detection. The developed and validated method for PRN analysis is excellent and applicable to a clinical study.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
  6. Rapid and direct determination of glyphosate, glufosinate, and aminophosphonic acid by online preconcentration CE with contactless conductivity detection
    See HH, Hauser PC, Ibrahim WA, Sanagi MM
    Electrophoresis, 2010 Jan;31(3):575-82.
    PMID: 20119968 DOI: 10.1002/elps.200900380
    Rapid and direct online preconcentration followed by CE with capacitively coupled contactless conductivity detection (CE-C(4)D) is evaluated as a new approach for the determination of glyphosate, glufosinate (GLUF), and aminophosphonic acid (AMPA) in drinking water. Two online preconcentration techniques, namely large volume sample stacking without polarity switching and field-enhanced sample injection, coupled with CE-C(4)D were successfully developed and optimized. Under optimized conditions, LODs in the range of 0.01-0.1 microM (1.7-11.1 microg/L) and sensitivity enhancements of 48- to 53-fold were achieved with the large volume sample stacking-CE-C(4)D method. By performing the field-enhanced sample injection-CE-C(4)D procedure, excellent LODs down to 0.0005-0.02 microM (0.1-2.2 microg/L) as well as sensitivity enhancements of up to 245- to 1002-fold were obtained. Both techniques showed satisfactory reproducibility with RSDs of peak height of better than 10%. The newly established approaches were successfully applied to the analysis of glyphosate, glufosinate, and aminophosphonic acid in spiked tap drinking water.
    Matched MeSH terms: Electrophoresis, Capillary/methods*
  7. Evaluation of groundwater quality and its suitability for drinking and agricultural use in Thanjavur city, Tamil Nadu, India
    Nagarajan R, Rajmohan N, Mahendran U, Senthamilkumar S
    Environ Monit Assess, 2010 Dec;171(1-4):289-308.
    PMID: 20072811 DOI: 10.1007/s10661-009-1279-9
    As groundwater is a vital source of water for domestic and agricultural activities in Thanjavur city due to lack of surface water resources, groundwater quality and its suitability for drinking and agricultural usage were evaluated. In this study, 102 groundwater samples were collected from dug wells and bore wells during March 2008 and analyzed for pH, electrical conductivity, temperature, major ions, and nitrate. Results suggest that, in 90% of groundwater samples, sodium and chloride are predominant cation and anion, respectively, and NaCl and CaMgCl are major water types in the study area. The groundwater quality in the study site is impaired by surface contamination sources, mineral dissolution, ion exchange, and evaporation. Nitrate, chloride, and sulfate concentrations strongly express the impact of surface contamination sources such as agricultural and domestic activities, on groundwater quality, and 13% of samples have elevated nitrate content (>45 mg/l as NO(3)). PHREEQC code and Gibbs plots were employed to evaluate the contribution of mineral dissolution and suggest that mineral dissolution, especially carbonate minerals, regulates water chemistry. Groundwater suitability for drinking usage was evaluated by the World Health Organization and Indian standards and suggests that 34% of samples are not suitable for drinking. Integrated groundwater suitability map for drinking purposes was created using drinking water standards based on a concept that if the groundwater sample exceeds any one of the standards, it is not suitable for drinking. This map illustrates that wells in zones 1, 2, 3, and 4 are not fit for drinking purpose. Likewise, irrigational suitability of groundwater in the study region was evaluated, and results suggest that 20% samples are not fit for irrigation. Groundwater suitability map for irrigation was also produced based on salinity and sodium hazards and denotes that wells mostly situated in zones 2 and 3 are not suitable for irrigation. Both integrated suitability maps for drinking and irrigation usage provide overall scenario about the groundwater quality in the study area. Finally, the study concluded that groundwater quality is impaired by man-made activities, and proper management plan is necessary to protect valuable groundwater resources in Thanjavur city.
    Matched MeSH terms: Environmental Monitoring/methods
  8. Assay and stability-indicating micellar electrokinetic chromatography method for the simultaneous determination of valacyclovir, acyclovir and their major impurity guanine in pharmaceutical formulations
    Al Azzam KM, Saad B, Makahleah A, Aboul-Enein HY, Elbashir AA
    Biomed Chromatogr, 2010 May;24(5):535-43.
    PMID: 19739243 DOI: 10.1002/bmc.1323
    A micellar electrokinetic chromatography (MEKC) method for the simultaneous determination of the antiviral drugs acyclovir and valacyclovir and their major impurity, guanine, was developed. The influences of several factors (surfactant and buffer concentration, pH, applied voltage, capillary temperature and injection time) were studied. Using tyramine hydrochloride as internal standard, the analytes were all separated in about 4 min. The separation was carried out in reversed polarity mode at 28 degrees C, 25 kV and using hydrodynamic injection (15 s). The separation was effected in a fused-silica capillary 100 microm x 56 cm and a background electrolyte of 20 mM citric acid-1 M Tris solution (pH 2.75), containing 125 mM sodium dodecyl sulphate and detection at 254 nm. The method was validated with respect to linearity, limit of detection and quantification, accuracy, precision and selectivity. Calibration curves were linear over the range 0.1-1 microg/mL (guanine) and from 0.1 to 120 microg/mL for both valacyclovir and acyclovir. The relative standard deviations of intra- and inter-day migration times and corrected peak areas were less than 5.0%. The proposed method was successfully applied to the determination of the analytes in tablets and creams. From the previous study it is concluded that the stability-indicating method developed for acyclovir and valacyclovir can be used for analysis of the drug in various stability samples.
    Matched MeSH terms: Chromatography, Micellar Electrokinetic Capillary/methods*
  9. Respirometric analysis of activated sludge models from palm oil mill effluent
    Damayanti A, Ujang Z, Salim MR, Olsson G, Sulaiman AZ
    Bioresour Technol, 2010 Jan;101(1):144-9.
    PMID: 19734044 DOI: 10.1016/j.biortech.2009.08.034
    Activated sludge models (ASMs) have been widely used as a basis for further model development in wastewater treatment processes. Values for parameters to be used are vital for the accuracy of the modeling approach. A continuous stirred tank reactor (CSTR), as open respirometer with continuous flow for 20 h is used in ASMs. The dissolved oxygen (DO) profile for 11 days was monitored. It was found the mass transfer coefficient K(La) is 0.3 h(-1) during lag and start feed phase and 0.01 h(-1) during stop feed phase, while the heterotrophic yield coefficient Y(H) is 0.44. Some of the chemical oxygen demand (COD) fractionations of palm oil mill effluent (POME) using respirometric test in ASM models are S(s) 50 mg/L, S(I) 16,600 mg/L, X(S) 25,550 mg/L, and X(I) 2,800 mg/L. The comparison of experimental and ASM1 from OUR concentration is found to fit well.
    Matched MeSH terms: Water Purification/methods*
  10. Comparison of the load at fracture of Turkom-Cera to Procera AllCeram and In-Ceram all-ceramic restorations
    AL-Makramani BM, Razak AA, Abu-Hassan MI
    J Prosthodont, 2009 Aug;18(6):484-8.
    PMID: 19694015
    PURPOSE: This study investigated the occlusal fracture resistance of Turkom-Cerafused alumina compared to Procera AllCeram and In-Ceram all-ceramic restorations.

    MATERIALS AND METHODS: Sixmaster dies were duplicated from the prepared maxillary first premolar tooth using nonprecious metal alloy (Wiron 99). Ten copings of 0.6 mm thickness were fabricated from each type of ceramic, for a total of thirty copings. Two master dies were used for each group, and each of them was used to lute five copings. All groups were cemented with resin luting cement Panavia F according to manufacturer's instructions and received a static load of 5 kg during cementation. After 24 hours of distilled water storage at 37 degrees C, the copings were vertically compressed using a universal testing machine at a crosshead speed of 1 mm/min.

    RESULTS: The results of the present study showed the following mean loads at fracture: Turkom-Cera (2184 +/- 164 N), In-Ceram (2042 +/- 200 N), and Procera AllCeram (1954 +/- 211 N). ANOVA and Scheffe's post hoc test showed that the mean load at fracture of Turkom-Cera was significantly different from Procera AllCeram (p < 0.05). Scheffe's post hoc test showed no significant difference between the mean load at fracture of Turkom-Cera and In-Ceram or between the mean load at fracture of In-Ceram and Procera AllCeram.

    CONCLUSION: Because Turkom-Cera demonstrated equal to or higher loads at fracture than currently accepted all-ceramic materials, it would seem to be acceptable for fabrication of anterior and posterior ceramic crowns.

    Matched MeSH terms: Dental Stress Analysis/methods
  11. 980-nm laser therapy versus varicose vein surgery in racially diverse Penang, Malaysia
    Lakhwani MN, Dadlani NI, Wong YC
    ANZ J Surg, 2009 May;79(5):352-7.
    PMID: 19566516 DOI: 10.1111/j.1445-2197.2009.04888.x
    Chronic venous disorders are conditions of increasing prevalence in the developing world, and venous ulceration is the terminal sequel. Currently there are only limited data on all aspects of this from Southeast Asia. The aim of the present study was to assess differences in the demography and outcome between varicose vein surgery (VVS) and the relatively new endovenous laser therapy (EVT) in patients from Penang, Malaysia.
    Matched MeSH terms: Laser Therapy/methods*
  12. A comparative study on the membrane based palm oil mill effluent (POME) treatment plant
    Ahmad AL, Chong MF, Bhatia S
    J Hazard Mater, 2009 Nov 15;171(1-3):166-74.
    PMID: 19573986 DOI: 10.1016/j.jhazmat.2009.05.114
    The discharge of palm oil mill effluent (POME) causes serious pollution problems and the membrane based POME treatment is suggested as a solution. Three different designs, namely Design A, B and C distinguished by their different types and orientations of membrane system are proposed. The results at optimum condition proved that the quality of the recovered water for all the designs met the effluent discharge standards imposed by the Department of Environment (DOE). The economic analysis at the optimum condition shows that the total treatment cost for Design A was the highest (RM 115.11/m(3)), followed by Design B (RM 23.64/m(3)) and Design C (RM 7.03/m(3)). In this study, the membrane system operated at high operating pressure with low membrane unit cost is preferable. Design C is chosen as the optimal design for the membrane based POME treatment system based on the lowest total treatment cost.
    Matched MeSH terms: Water Purification/methods*
  13. Measuring organic carbon, nutrients and heavy metals in rivers receiving leachate from controlled and uncontrolled municipal solid waste (MSW) landfills
    Yusof N, Haraguchi A, Hassan MA, Othman MR, Wakisaka M, Shirai Y
    Waste Manag, 2009 Oct;29(10):2666-80.
    PMID: 19564103 DOI: 10.1016/j.wasman.2009.05.022
    Since landfilling is the common method of waste disposal in Malaysia, river water is greatly exposed to the risk of contamination from leachate unless proper leachate management is carried out. In this study, leachates from three different types of landfills, namely active uncontrolled, active controlled and closed controlled, were characterized, and their relationships with river water chemistry were examined monthly for a year. The influence of leachate on river water chemistry from each type of landfill depended on many factors, including the presence of a leachate control mechanism, leachate characteristics, precipitation, surface runoff and the applied treatment. The impact of leachate from an active uncontrolled landfill was the highest, as the organic content, NH(4)(+)-N, Cd and Mn levels appeared high in the river. At the same time, influences of leachate were also observed from both types of controlled landfills in the form of inorganic nitrogen (NH(4)(+)-N, NO(3)(-)-N and NO(2)(-)-N) and heavy metals (Fe, Cr, Ni and Mn). Improper treatment practice led to high levels of some contaminants in the stream near the closed controlled landfill. Meanwhile, the active controlled landfill, which was located near the coastline, was exposed to the risk of contamination resulting from the pyrite oxidation of the surrounding area.
    Matched MeSH terms: Refuse Disposal/methods*
  14. Treatment of Terasil Red R dye wastewater using H2O2/pyridine/Cu(II) system
    Lim CL, Morad N, Teng TT, Ismail N
    J Hazard Mater, 2009 Aug 30;168(1):383-9.
    PMID: 19303709 DOI: 10.1016/j.jhazmat.2009.02.061
    The H(2)O(2)/pyridine/Cu(II) advanced oxidation system was used to assess the efficiency of the treatment of a 1 g L(-1) Terasil Red R dye solution. This system was found to be capable in reducing the concentration of chemical oxygen demand (COD) of the dye solution up to 90%, and achieving 99% in decolorization at the optimal concentration of 5.5mM H(2)O(2), 38 mM pyridine and 1.68 mM Cu(II). The final concentration of COD was recorded at 117 mg L(-1) and color point at 320 PtCo. Full 2(4) factorial design and the response surface methodology using central composite design (CCD) were utilized in the screening and optimization of this study. Treatment efficiency was found to be pH independent. The amount of sludge generation was in the range of 100-175 mg L(-1) and the sludge produced at the optimal concentration was 170 mg L(-1).
    Matched MeSH terms: Water Purification/methods
  15. Validation of LC for the determination of alpha-mangostin in mangosteen peel extract: a tool for quality assessment of Garcinia mangostana L
    Yodhnu S, Sirikatitham A, Wattanapiromsakul C
    J Chromatogr Sci, 2009 Mar;47(3):185-9.
    PMID: 19298703
    Mangosteen, Garcinia mangostana L., is known as the "Queen of fruits" and can be cultivated in the tropical rainforest such as Malaysia, Indonesia, and Thailand. Compounds isolated from the fruit peel of mangosteen contain abundant xanthones (especially alpha-mangostin). It has been used as traditional medicine such as anti-inflammatory and antibacterial and is popularly applied to cosmetic and pharmaceutical products. However, there is little information for quality and quantity determination of alpha-mangostin in mangosteen. Thus, the aim of this study was to set up a validated and stability-indicated isocratic reverse-phase high-performance liquid chromatographic (HPLC) method for quality control and quantity determination of a-mangostin from mangosteen peel extract. The assay was fully validated and shown to be linear (r(2) > 0.999), sensitive (LOD = 0.02 microg/mL and LOQ = 0.08 microg/mL), accurate (intra-day was between 98.1-100.8%, inter-day was between 90.0-101.3%), precise (intra-day variation < or = 1.8%, inter-day variation < or = 4.3%), specific, and with good recovery. Total analysis was approximately 8 min. The finalized method is also a stability-indicating assay. The present method should be useful for analytical research and for routine quality control analysis of alpha-mangostin in mangosteen peel extract and products of mangosteen.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
  16. Radiological monitoring: terrestrial natural radionuclides in Kinta District, Perak, Malaysia
    Lee SK, Wagiran H, Ramli AT, Apriantoro NH, Wood AK
    J Environ Radioact, 2009 May;100(5):368-74.
    PMID: 19299052 DOI: 10.1016/j.jenvrad.2009.01.001
    Natural background gamma radiation and radioactivity concentrations were investigated from 2003 to 2005 in Kinta District, Perak, Malaysia. Sample locations were distant from any 'amang' processing plants. The external gamma dose rates ranged from 39 to 1039 nGy h(-1). The mean external gamma dose rate was 222+/-191 nG yh(-1). Small areas of relatively enhanced activity were located having external gamma dose rates of up to 1039+/-104 nGy h(-1). The activity concentrations of (238)U, (232)Th and (40)K were analyzed by using a high-resolution co-axial HPGe detector system. The activity concentration ranges were 12-426 Bq kg(-1) for (238)U, 19-1377 Bq kg(-1) for (232)Th and <19-2204 Bq kg(-1) for (40)K. Based on the radioactivity levels determined, the gamma-absorbed dose rates in air at 1m above the ground were calculated. The calculated dose rates and measured dose rates had a good correlation coefficient, R of 0.94. To evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity, the gamma-absorbed dose rate and the mean population weighted dose rate were calculated. An isodose map for the Kinta District was also produced.
    Matched MeSH terms: Radiation Monitoring/methods
  17. Remediation of sulfidic wastewater by catalytic oxidation with hydrogen peroxide
    Ahmad N, Maitra S, Dutta BK, Ahmad F
    J Environ Sci (China), 2009;21(12):1735-40.
    PMID: 20131606
    Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and ammonia. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-Ray diffraction analysis, scanning electrom microscope and energy dispersive X-ray analysis. The catalyst was quite effective in oxidizing the sulfide by hydrogen peroxide. The effects of sulfide concentration, catalyst loading, H2O2 dosing and temperature on the kinetics of sulfide oxidation were investigated. Kinetic equations and activation energies for the catalytic oxidation reaction were calculated based on the experimental results.
    Matched MeSH terms: Waste Management/methods*
  18. Tissue engineering approach to repair abdominal wall defects using cell-seeded bovine tunica vaginalis in a rabbit model
    Ayele T, Zuki AB, Noorjahan BM, Noordin MM
    J Mater Sci Mater Med, 2010 May;21(5):1721-30.
    PMID: 20135201 DOI: 10.1007/s10856-010-4007-7
    The aim of this study was to engineer skeletal muscle tissue for repair abdominal wall defects. Myoblast were seeded onto the scaffolds and cultivated in vitro for 5 days. Full thickness abdominal wall defects (3 x 4 cm) were created in 18 male New Zealand white rabbits and randomly divided into two equal groups. The defects of the first group were repaired with myoblast-seeded-bovine tunica vaginalis whereas the second group repaired with non-seeded-bovine tunica vaginalis and function as a control. Three animals were sacrificed at 7th, 14th, and 30th days of post-implantation from each group and the explanted specimens were subjected to macroscopic and microscopic analysis. In every case, seeded scaffolds have better deposition of newly formed collagen with neo-vascularisation than control group. Interestingly, multinucleated myotubes and myofibers were only detected in cell-seeded group. This study demonstrated that myoblast-seeded-bovine tunica vaginalis can be used as an effective scaffold to repair severe and large abdominal wall defects with regeneration of skeletal muscle tissue.
    Matched MeSH terms: Tissue Engineering/methods*
  19. A study into salivary-based measurement of human stress subjected to Ellestad stress test protocol
    Lee YK, Za'aba A, Madzhi NK, Ahmad A
    Annu Int Conf IEEE Eng Med Biol Soc, 2009;2009:765-8.
    PMID: 19964239 DOI: 10.1109/IEMBS.2009.5333674
    Previous works on the effects of salivary alpha amylase in respond to various stressors report encouraging findings on it being a good indicator of stress. Ellestad protocol is a clinical procedure to screen for coronary artery disease by introducing exercise induced physical stress. If a salivary based biomarker profile in accordance to a stress test protocol could be established, the critical stress state which disable rational decision making could be ascertained in a standardized procedure. This technique would serve to aid human resource management in times of critical events such as rescue, firefighting or even military, that would potentially prevent unnecessary sacrifice of human lives. In this pilot study with five healthy volunteers performing the Ellestad protocol treadmill, a measurement profile with physiologic and salivary based biomarker is obtained. It is found that the alpha amylase levels or the changes in it as workload changes from resting-walking-running at ease-exhaustive running, is relatively more significant in reflecting the stress state than heart rate and blood pressure. Moreover, it is strongly associated with mood state with correlation coefficient of 0.8 and significance of 0.01.
    Matched MeSH terms: Exercise Test/methods*
  20. Liquefaction of kenaf (Hibiscus cannabinus L.) core for wood laminating adhesive
    Juhaida MF, Paridah MT, Mohd Hilmi M, Sarani Z, Jalaluddin H, Mohamad Zaki AR
    Bioresour Technol, 2010 Feb;101(4):1355-60.
    PMID: 19833509 DOI: 10.1016/j.biortech.2009.09.048
    A study was carried out to produce polyurethane (PU) as a wood laminating adhesive from liquefied kenaf core (LKC) polyols by reacting it with toluene-2,4-diisocyanate (TDI) and 1,4-butanediol (BDO). The LKC polyurethane (LKCPU) adhesive has a molecular weight (MW) of 2666, viscosity of 5370 mPa s, and solids content of 86.9%. The average shear strength of the rubberwood (RW) bonded with LKCPU adhesive was 2.9 MPa. Most of the sheared specimens experienced a total adhesive failure. The formation of air bubbles through the liberation of carbon dioxide was observed to reduce the adhesive penetration and bonding strength which was obviously seen on the sheared specimens. The percentage of catalyst used can be varied based on the usage and working time needed. Nonetheless, the physical properties of LKCPU produced in this work had shown good potential as edge-bonding adhesive.
    Matched MeSH terms: Biotechnology/methods*
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