Displaying publications 1 - 20 of 35 in total

Abstract:
Sort:
  1. Hossain MS, Nik Ab Rahman NN, Balakrishnan V, Alkarkhi AF, Ahmad Rajion Z, Ab Kadir MO
    Waste Manag, 2015 Apr;38:462-73.
    PMID: 25636860 DOI: 10.1016/j.wasman.2015.01.003
    Clinical solid waste (CSW) poses a challenge to health care facilities because of the presence of pathogenic microorganisms, leading to concerns in the effective sterilization of the CSW for safe handling and elimination of infectious disease transmission. In the present study, supercritical carbon dioxide (SC-CO2) was applied to inactivate gram-positive Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis, and gram-negative Escherichia coli in CSW. The effects of SC-CO2 sterilization parameters such as pressure, temperature, and time were investigated and optimized by response surface methodology (RSM). Results showed that the data were adequately fitted into the second-order polynomial model. The linear quadratic terms and interaction between pressure and temperature had significant effects on the inactivation of S. aureus, E. coli, E. faecalis, and B. subtilis in CSW. Optimum conditions for the complete inactivation of bacteria within the experimental range of the studied variables were 20 MPa, 60 °C, and 60 min. The SC-CO2-treated bacterial cells, observed under a scanning electron microscope, showed morphological changes, including cell breakage and dislodged cell walls, which could have caused the inactivation. This espouses the inference that SC-CO2 exerts strong inactivating effects on the bacteria present in CSW, and has the potential to be used in CSW management for the safe handling and recycling-reuse of CSW materials.
  2. Mannan Baig A, Khan NA, Effendi V, Rana Z, Ahmad HR, Abbas F
    Anticancer Drugs, 2017 01;28(1):75-87.
    PMID: 27606721
    Recent reports on acetylcholine muscarinic receptor subtype 3 (CHRM3) have shown its growth-promoting role in prostate cancer. Additional studies report the proliferative effect of the cholinergic agonist carbachol on prostate cancer by its agonistic action on CHRM3. This study shows that the type 1 acetylcholine muscarinic receptor (CHRM1) contributes toward the proliferation and growth of prostate cancer. We used growth and cytotoxic assays, the prostate cancer microarray database and CHRM downstream pathways' homology of CHRM subtypes to uncover multiple signals leading to the growth of prostate cancer. Growth assays showed that pilocarpine stimulates the proliferation of prostate cancer. Moreover, it shows that carbachol exerts an additional agonistic action on nicotinic cholinergic receptor of prostate cancer cells that can be blocked by tubocurarine. With the use of selective CHRM1 antagonists such as pirenzepine and dicyclomine, a considerable inhibition of proliferation of prostate cancer cell lines was observed in dose ranging from 15-60 µg/ml of dicyclomine. The microarray database of prostate cancer shows a dominant expression of CHRM1 in prostate cancer compared with other cholinergic subtypes. The bioinformatics of prostate cancer and CHRM pathways show that the downstream signalling include PIP3-AKT-CaM-mediated growth in LNCaP and PC3 cells. Our study suggests that antagonism of CHRM1 may be a potential therapeutic target against prostate cancer.
  3. Banch TJH, Hanafiah MM, Alkarkhi AFM, Abu Amr SS
    Polymers (Basel), 2019 Aug 14;11(8).
    PMID: 31416151 DOI: 10.3390/polym11081349
    In this study, tannin-based natural coagulant was used to treat stabilized landfill leachate. Tannin modified with amino group was utilized for the treatment process. Central composite design (CCD) was used to investigate and optimize the effect of tannin dosage and pH on four responses. The treatment efficiency was evaluated based on the removal of four selected (responses) parameters; namely, chemical oxygen demand (COD), color, NH3-N and total suspended solids (TSS). The optimum removal efficiency for COD, TSS, NH3-N and color was obtained using a tannin dosage of 0.73 g at a pH of 6. Moreover, the removal efficiency for selected heavy metals from leachate; namely, iron (Fe2+), zinc (Zn2+), copper (Cu2+), chromium (Cr2+), cadmium (Cd2+), lead (Pb2+), arsenic (As3+), and cobalt (Co2+) was also investigated. The results for removal efficiency for COD, TSS, NH3-N, and color were 53.50%, 60.26%, and 91.39%, respectively. The removal of selected heavy metals from leachate for Fe2+, Zn2+, Cu2+, Cr2+, Cd2+, Pb2+, As3+ and cobalt Co2+ were 89.76%, 94.61%, 94.15%, 89.94%, 17.26%, 93.78%, 86.43% and 84.19%, respectively. The results demonstrate that tannin-based natural coagulant could effectively remove organic compounds and heavy metals from stabilized landfill leachate.
  4. Abu Amr SS, Alkarkhi AFM, Alslaibi TM, Abujazar MSS
    Data Brief, 2018 Aug;19:951-958.
    PMID: 29900392 DOI: 10.1016/j.dib.2018.05.111
    Although landfilling is still the most suitable method for solid waste disposal, generation of large quantity of leachate is still considered as one of the main environmental problem. Efficient treatment of leachate is required prior to final discharge. Persulfate (S2O82-) recently used for leachate oxidation, the oxidation potential of persulfate can be improved by activate and initiate sulfate radical. The current data aimed to evaluate the performance of utilizing Al2SO4 reagent for activation of persulfate to treat landfill leachate. The data on chemical oxygen demand (COD), color, and NH3-H removals at different setting of the persulfate, Al2SO4 dosages, pH, and reaction time were collected using a central composite design (CCD) were measured to identify the optimum operating conditions. A total of 30 experiments were performed, the optimum conditions for S2O82-/Al2SO4 oxidation process was obtained. Quadratic models for chemical oxygen demand (COD), color, and NH3-H removals were significant with p-value 
  5. Syimir Fizal AN, Sohrab Hossain M, Alkarkhi AFM, Oyekanmi AA, Hashim SRM, Khalil NA, et al.
    Heliyon, 2019 Aug;5(8):e02368.
    PMID: 31485542 DOI: 10.1016/j.heliyon.2019.e02368
    Understanding the tanker driver hazard awareness on chemical exposure is important to ensure that they are fortified with the appropriate information regarding the risk of their occupation. This present study was conducted to determine the awareness of the petrol tanker driver on the chemical exposure during transportation petroleum product. The assessment on hazardous awareness of the petrol tank driver was conducted through questionnaire survey. Wherein, the questionnaire was designed with considering the variables of age of the driver, working experience, working hours in a day and knowledge on chemical hazard presence in the petroleum oil. A reliability test of Cronbach's Alpha was performed to validate the questionnaire and the Chi-Square test was conducted to determine the correlation among the studied variables. The findings of the present study revealed that the drivers who are frequently come into direct contact with petrol cannot identify the spillage had occurred during working. The study identified that there is an urgency to conduct training on safe handling of petroleum oil in order to eliminate the risk of chemical hazards exposure to the tanker driver.
  6. Chang SH, Teng TT, Ismail N, Alkarkhi AF
    J Hazard Mater, 2011 Jun 15;190(1-3):197-204.
    PMID: 21493005 DOI: 10.1016/j.jhazmat.2011.03.025
    The objectives of this work were to select suitable design parameters and optimize the operating parameters of a soybean oil-based bulk liquid membrane (BLM) for Cu(II) removal and recovery from aqueous solutions. The soybean oil-based BLM consists of an aqueous feed phase (Cu(II) source), an organic membrane phase (soybean oil (diluent), di-2-ethylhexylphosphoric acid (D2EHPA) (carrier) and tributylphosphate (phase modifier)) and an aqueous stripping phase (sulfuric acid solution (H(2)SO(4))). Effects of design parameters (stirring condition and stripping/membrane to feed/membrane interface area ratio) of soybean oil-based BLM on the Cu(II) removal and recovery from aqueous solutions were investigated and the suitable parameters were selected for further studies. Optimization of the operating parameters (D2EHPA concentration, H(2)SO(4) concentration, stirring speed, temperature and operating time) of soybean oil-based BLM for maximum percentage (%) recovery of Cu(II) was then conducted using Response Surface Methodology and the optimum parameters were determined. A regression model for % recovery was developed and its adequacy was evaluated. The experimental % recovery obtained under the optimum operating conditions was compared with the predicted one and they were found to agree satisfactorily with each other.
  7. Yusup Y, Kayode JS, Alkarkhi AFM
    MethodsX, 2018;5:448-453.
    PMID: 30090703 DOI: 10.1016/j.mex.2018.05.003
    The southern South China coastal oceans within the South East Asian region are much lacking in the perception of the surface energy budget and evaporation over the ocean waters in response to climatic changes. The eddy covariance method was used to measure the energy fluxes, microclimate variables, and surface water temperature from November 2015 to October 2017 at the Straits of Malacca, South China Sea; Pulau Pinang, Malaysia, situated at latitude 5°28'06″N, and longitude 100°12'01″E. This work focused on the methodological approach to the air-sea energy fluxes data collection and analysis. In this regard, the method applied for the direct measurements and analysis of energy fluxes and other meteorological parameters in the site is considered and reported. •The paper summarizes the analysis of energy fluxes, microclimate variables, and surface water temperature data in a tropical coastal ocean station using the eddy covariance method.•The methodological approach illustrates the method of analysis applied in this study which can be compared and used for similar studies in other places.•The reproducible data analysis technique matches similar comparative methods such as Matlab and Python.
  8. Yusup Y, Kayode JS, Alkarkhi AFM
    Data Brief, 2018 Aug;19:1477-1481.
    PMID: 30229020 DOI: 10.1016/j.dib.2018.06.020
    Air-sea flux exchanges influence the climate condition and the global carbon-moisture cycle. It is imperative to understand the fundamentals of the natural systems at the tropical coastal ocean and how the transformation takes place over the time. Hence, latent and sensible heat fluxes, microclimate variables, and surface water temperature data were collected using eddy covariance instruments mounted on a platform at a tropical coastal ocean station from November 2015 to October 2017. The research data is to gain the needful knowledge of the energy exchanges in the tropical climatic environment to further improve predictive algorithms or models. Therefore, it is intended that this data report will offer appropriate information for the Monsoonal, and diurnal patterns of latent (LE) and sensible (H) heats and hence, establish the relationship between microclimate variables on the energy fluxes at the peninsular Malaysian tropical coastal ocean.
  9. Yusup Y, Kayode JS, Alkarkhi AFM
    Data Brief, 2018 Dec;21:13-17.
    PMID: 30310834 DOI: 10.1016/j.dib.2018.09.108
    Data on the micrometeorological parameters and Energy Fluxes at an intertidal zone of a Tropical Coastal Ocean was carried out on an installed eddy covariance instruments at a Muka head station in the north-western end of the Pinang Island (5°28'06''N, 100°12'01''E), Peninsula Malaysia. The vast source of the supply of energy and heat to the hydrologic and earth׳s energy cycles principally come from the oceans. The exchange of energies via air-sea interactions is crucial to the understanding of climate variability, energy, and water budget. The turbulent energy fluxes are primary mechanisms through which the ocean releases the heat absorbed from the solar radiations to the environment. The eddy covariance (EC) system is the direct technique of measuring the micrometeorological parameters which allow the measurement of these turbulent fluxes in the time scale of half-hourly basis at 20 Hz over a long period. The data being presented is the comparison of the two-year seasonality patterns of monsoons variability on the measured microclimate variables in the southern South China Sea coastal area.
  10. Yahya S, Moghavvemi M, Almurib HA
    Sensors (Basel), 2012;12(6):6869-92.
    PMID: 22969326 DOI: 10.3390/s120606869
    Research on joint torque reduction in robot manipulators has received considerable attention in recent years. Minimizing the computational complexity of torque optimization and the ability to calculate the magnitude of the joint torque accurately will result in a safe operation without overloading the joint actuators. This paper presents a mechanical design for a three dimensional planar redundant manipulator with the advantage of the reduction in the number of motors needed to control the joint angle, leading to a decrease in the weight of the manipulator. Many efforts have been focused on decreasing the weight of manipulators, such as using lightweight joints design or setting the actuators at the base of the manipulator and using tendons for the transmission of power to these joints. By using the design of this paper, only three motors are needed to control any n degrees of freedom in a three dimensional planar redundant manipulator instead of n motors. Therefore this design is very effective to decrease the weight of the manipulator as well as the number of motors needed to control the manipulator. In this paper, the torque of all the joints are calculated for the proposed manipulator (with three motors) and the conventional three dimensional planar manipulator (with one motor for each degree of freedom) to show the effectiveness of the proposed manipulator for decreasing the weight of the manipulator and minimizing driving joint torques.
  11. Khan MK, Abbas F, Godil DI, Sharif A, Ahmed Z, Anser MK
    Environ Sci Pollut Res Int, 2021 Oct;28(39):55579-55591.
    PMID: 34138439 DOI: 10.1007/s11356-021-14686-9
    Without enhancing the quality of the environment, the goals of sustainable development remain unachievable. In order to minimize the damage to the planet, sustainable practices need to be considered. This study is conducted to identify some of the drivers behind the increasing sustainability issues and tried to investigate the impact of natural resources, financial development, and economic growth on the ecological footprint in Malaysia from the year 1980-2019 by utilizing the dynamic simulated autoregressive distribution lag approach. It was identified that financial development, economic growth, and natural resources are the determinants behind the upsurge of the ecological footprint as all three show a positive and significant effect on ecological footprint. However, in the long run, the presence of the Environmental Kuznets Curve hypothesis was also validated in Malaysia. Therefore, it is recommended to increase awareness among the public regarding the adoption of sustainable practices in everyday life and to use green technologies that offer maximum efficiency and minimum damage to the environment in commercial and domestic activities. Finally, based on the research results, a comprehensive policy framework was proposed which could allow the Malaysian economy to attain the objectives of Sustainable Development Goals (SDGs) 7, 8, and 13.
  12. Fatemeh, S. R., Saifullah, R., Abbas, F. M. A., Azhar, M. E.
    MyJurnal
    The influence of variety (Cavendish and Dream), stage of ripeness (green and ripe) and parts (pulp and peel) on antioxidative compounds and antioxidant activity of banana fruit was investigated. The TPC and TFC ranged widely from 75.01 to 685.57 mg GAE/100 g and 39.01 to 389.33 mg CEQ/100 g of dry matter respectively. Cavendish banana flour contained higher TPC and TFC compared to Dream variety. TPC and TFC values of banana peel were higher than those of banana pulp. Also, green banana showed higher TPC and TFC values than those of ripe fruit. Radical scavenging activities (inhibition of DPPH) of the extracts ranged from 26.55 to 52.66%. Although Dream banana peel extracts appeared to have low TPC and TFC, its antioxidant activities were ranked moderate to high. This implies that antioxidative compounds other than phenolics and flavonoids were probably responsible for inhibition of DPPH.
  13. Ng, K. F., Abbas, F. M. A., Tan, T. C., Azhar, M. E.
    MyJurnal
    Proximate composition, pH and amylose content of ripe Cavendish banana flour (RBF) prepared in this study were compared with all-purpose wheat flour (WF). RBF was found to be significantly (P < 0.05) higher in total carbohydrates and minerals content, while significantly (P < 0.05) lower in protein and fat contents compared with those of WF. Wheat-ripe banana composite flours (W-RBF) prepared by partial substitution of WF with RBF were assessed for swelling power, solubility, pasting properties and gel textural properties. Granular swelling of RBF occurred at a higher temperature compared to that of WF, suggesting that more energy and water were required to cook WF-RBF as the presence of soluble carbohydrates would compete for water and this would eventually delay starch hydration and granular expansion during cooking. Higher substitution with RBF led to higher soluble carbohydrates content, and increase in solubility index of WF-RBF. Partial substitution with RBF also resulted in significant (P < 0.05) decrease in pasting properties. A higher substitution of WF with RBF could reduce starch gelatinisation during cooking and retrogradation owing to the reduction of available starch in WF-RBF. All WF-RBF gels were significantly (P < 0.05) firmer and less sticky compared to WF gels.
  14. Alkarkhi AF, Lim HK, Yusup Y, Teng TT, Abu Bakar MA, Cheah KS
    J Environ Manage, 2013 Jun 15;122:121-9.
    PMID: 23570974 DOI: 10.1016/j.jenvman.2013.03.010
    The ability of aluminum coagulant extracted from red earth to treat Terasil Red R (disperse) and Cibacron Red R (reactive) synthetic dye wastewater was studied. The effects of extractant concentration, soil-to-volume of extractant ratio, and the types of extracting agents (NaOH vs. KCl) on the concentration of aluminum extracted were also investigated. In addition, the efficiency of extracted aluminum was compared with aluminum sulfate, in terms of its capability to reduce the chemical oxygen demand (COD) and to remove synthetic color. Factorial design was applied to determine the effect of selected factors on the amount of aluminum extracted from red earth (i.e., pH, dose of coagulant, type of coagulant on COD reduction, and color removal). It was found that only selected factors exhibited a significant effect on the amount of aluminum extracted from red earth. It was also determined that all factors and their interactions exhibited a significant effect on COD reduction and color removal when applying the extracted aluminum in a standard coagulation process. The results were also compared to aluminum sulfate. Furthermore, NaOH was found to be a better extractant of aluminum in red earth than KCl. Therefore, the best extracting conditions for both extractants were as follows: 2 M NaOH and in a 1:5 (soil/volume of extractant) ratio; 1 M KCl and 1:5 ratio. In treating synthetic dye wastewater, the extracted coagulant showed comparable treatment efficiency to the commercial coagulant. The extracted coagulant was able to reduce the COD of the dispersed dye by 85% and to remove 99% of the color of the dispersed dye, whereas the commercial coagulant reduced 90% of the COD and removed 99% of the color of the dispersed dye. Additionally, the extracted coagulant was able to reduce the COD of the reactive dye by 73% and to remove 99% of the color of the reactive dye. However, the commercial coagulant managed to reduce the COD of the reactive dye by 94% and to remove 96% of the color for the reactive dye.
  15. Alkarkhi AFM, Alqaraghuli WAA, Yusup Y, Abu Amr SS, Mahmud MN, Dewayantoa N
    Data Brief, 2019 Jun;24:103894.
    PMID: 31011604 DOI: 10.1016/j.dib.2019.103894
    This article presents data relating to the changes in absorbance of glucose during the acid hydrolysis of sugarcane bagasse using sulphuric acid. This dataset also contains the moisture content, volatile matter, and fixed carbon of the sugarcane bagasse. The results of the analysis of variance (ANOVA) and the interaction plots between reaction time, temperature, and ratio are also presented. The data revealed that absorbance of glucose is increasing by increasing the temperature and time. Moreover, the best ratio for the highest absorbance of glucose was achieved at 1:20.
  16. Ulutaş K, Abujayyab SKM, Abu Amr SS, Alkarkhi AFM, Duman S
    Theor Appl Climatol, 2023;152(1-2):801-812.
    PMID: 37016660 DOI: 10.1007/s00704-023-04420-5
    Different health management strategies may need to be implemented in different regions to cope with diseases. The current work aims to evaluate the relationship between air quality parameters and the number of new COVID-19 cases in two different geographical locations, namely Western Anatolia and Western Black Sea in Turkey. Principal component analysis (PCA) and regression model were utilized to describe the effect of environmental parameters (air quality and meteorological parameters) on the number of new COVID-19 cases. A big difference in the mean values for all air quality parameters has appeared between the two areas. Two regression models were developed and showed a significant relationship between the number of new cases and the selected environmental parameters. The results showed that wind speed, SO2, CO, NOX, and O3 are not influential variable and does not affect the number of new cases of COVID-19 in the Western Black Sea area, while only wind speed, SO2, CO, NOX, and O3 are influential parameters on the number of new cases in Western Anatolia. Although the environmental parameters behave differently in each region, these results revealed that the relationship between the air quality parameters and the number of new cases is significant.
  17. Yeoh SY, Alkarkhi AF, Ramli SB, Easa AM
    Int J Food Sci Nutr, 2011 Jun;62(4):410-7.
    PMID: 21306189 DOI: 10.3109/09637486.2010.539555
    Yellow alkaline noodles (YAN) prepared by partial substitution of wheat flour with soy protein isolate and treated with microbial transglutaminase (MTG) and ribose were investigated during cooking. Cooking caused an increase in lightness but a decrease in redness and yellowness, pH, tensile strength and elasticity values of noodles. The extents of these changes were influenced by formulation and cross-linking treatments. The pH and lightness for YAN-ribose were lowest but the yellowness and redness were the highest whilst the tensile strength and elasticity values remained moderate. For YAN-MTG, the color and pH values were moderate, but tensile strength and elasticity values were the highest. YAN prepared with both cross-linking agents had physical values between YAN-ribose and YAN-MTG. Although certain sensory parameters showed differences in score, the overall acceptability of all 10-min-cooked YAN was similar. It is possible to employ cross-linking agents to improve physical properties of cooked YAN.
  18. Wai WW, Alkarkhi AF, Easa AM
    J Food Sci, 2009 Oct;74(8):C637-41.
    PMID: 19799660 DOI: 10.1111/j.1750-3841.2009.01331.x
    Response surface methodology (RSM) was carried out to study the effect of temperature, pH, and heating time as input variables on the yield and degree of esterification (DE) as the output (responses). The results showed that yield and DE of extracted pectin ranged from 2.27% to 9.35% (w/w, based on dry weight of durian rind) and 47.66% to 68.6%, respectively. The results also showed that a 2nd-order model adequately fitted the experimental data for the yield and DE. Optimum condition for maximum yield and DE was achieved at 85 degrees C, a time of either 4 or 1 h, and a pH of 2 or 2.5.
  19. Gan CY, Alkarkhi AF, Easa AM
    J Biosci Bioeng, 2009 Apr;107(4):366-72.
    PMID: 19332294 DOI: 10.1016/j.jbiosc.2008.12.007
    D-optimal design was employed to optimize the mixture of cross-linking agents formulation: microbial transglutaminase (MTGase) and ribose, and the processing parameters (i.e. incubation and heating time) in the mixture in order to obtain combined-cross-linked bovine serum albumin gels that have high gel strength, pH close to neutral and yet medium in browning. Analysis of variance (ANOVA) showed that the contribution of quadratic term to the model over the linear was significant for pH and L* value, whereas linear model was significant for gel strength. Optimization study using response surface methodology (RSM) was performed to the mixture components and process variables and the optimum conditions obtained were: MTGase of 1.34-1.43 g/100 mL, ribose of 1.07-1.16 g/100 mL, incubation time of 5 h at 40 degrees C and heating time of 3 h at 90 degrees C.
  20. Alkarkhi AF, Ramli SB, Easa AM
    Int J Food Sci Nutr, 2009;60 Suppl 4:116-25.
    PMID: 19115121 DOI: 10.1080/09637480802609368
    Major (sodium, potassium, calcium, magnesium) and minor elements (iron, copper, zinc, manganese) and one heavy metal (lead) of Cavendish banana flour and Dream banana flour were determined, and data were analyzed using multivariate statistical techniques of factor analysis and discriminant analysis. Factor analysis yielded four factors explaining more than 81% of the total variance: the first factor explained 28.73%, comprising magnesium, sodium, and iron; the second factor explained 21.47%, comprising only manganese and copper; the third factor explained 15.66%, comprising zinc and lead; while the fourth factor explained 15.50%, comprising potassium. Discriminant analysis showed that magnesium and sodium exhibited a strong contribution in discriminating the two types of banana flour, affording 100% correct assignation. This study presents the usefulness of multivariate statistical techniques for analysis and interpretation of complex mineral content data from banana flour of different varieties.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links