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  1. Thung WE, Ong SA, Ho LN, Wong YS, Ridwan F, Oon YL, et al.
    J Environ Sci (China), 2018 Apr;66:295-300.
    PMID: 29628097 DOI: 10.1016/j.jes.2017.05.010
    This study demonstrated the potential of single chamber up-flow membrane-less microbial fuel cell (UFML-MFC) in wastewater treatment and power generation. The purpose of this study was to evaluate and enhance the performance under different operational conditions which affect the chemical oxygen demand (COD) reduction and power generation, including the increase of KCl concentration (MFC1) and COD concentration (MFC2). The results showed that the increase of KCl concentration is an important factor in up-flow membrane-less MFC to enhance the ease of electron transfer from anode to cathode. The increase of COD concentration in MFC2 could led to the drop of voltage output due to the prompt of biofilm growth in MFC2 cathode which could increase the internal resistance. It also showed that the COD concentration is a vital issue in up-flow membrane-less MFC. Despite the COD reduction was up to 96%, the power output remained constrained.
    Matched MeSH terms: Waste Water
  2. Chen W, Li H, Hou E, Wang S, Wang G, Panahi M, et al.
    Sci Total Environ, 2018 Sep 01;634:853-867.
    PMID: 29653429 DOI: 10.1016/j.scitotenv.2018.04.055
    The aim of the current study was to produce groundwater spring potential maps using novel ensemble weights-of-evidence (WoE) with logistic regression (LR) and functional tree (FT) models. First, a total of 66 springs were identified by field surveys, out of which 70% of the spring locations were used for training the models and 30% of the spring locations were employed for the validation process. Second, a total of 14 affecting factors including aspect, altitude, slope, plan curvature, profile curvature, stream power index (SPI), topographic wetness index (TWI), sediment transport index (STI), lithology, normalized difference vegetation index (NDVI), land use, soil, distance to roads, and distance to streams was used to analyze the spatial relationship between these affecting factors and spring occurrences. Multicollinearity analysis and feature selection of the correlation attribute evaluation (CAE) method were employed to optimize the affecting factors. Subsequently, the novel ensembles of the WoE, LR, and FT models were constructed using the training dataset. Finally, the receiver operating characteristic (ROC) curves, standard error, confidence interval (CI) at 95%, and significance level P were employed to validate and compare the performance of three models. Overall, all three models performed well for groundwater spring potential evaluation. The prediction capability of the FT model, with the highest AUC values, the smallest standard errors, the narrowest CIs, and the smallest P values for the training and validation datasets, is better compared to those of other models. The groundwater spring potential maps can be adopted for the management of water resources and land use by planners and engineers.
    Matched MeSH terms: Water Resources
  3. Umar Kassim, Omar Mohd Rohim
    MyJurnal
    In accordance upon conservation efforts, this research emphasizes on prevention of
    environmental pollution and considers the elements of sustainable of infrastructure
    construction materials, which is interlocking pavement block. The development of this
    innovative product apply the concept of 3Rs and waste to wealth by using the
    agricultural waste product, coconut shell, where widely available with very minimum
    cost worldwide especially in tropical country such as India, Indonesia, Philippines,
    Thailand and Malaysia. The main objective of this research is to produce an
    environmental friendly product with a good quality, low cost and lightweight known as
    Green Interlocking Pavement (GIP Block). The chemical composition of coconut shell
    ash and ordinary Portland cement being identified and compared to know whether it
    is able to react as a good binder in the mixture or not. The quality of GIP Block
    considered is compressive strength, water absorption and bulk density. All the blocks
    were curing in seven and 28 days before implementing the entire test. The existing
    interlocking pavement used as bench mark and GIP Block 0% of proportion of coconut
    shell ash used as control variables. The specimen of the interlocking pavement
    prepared in this research is 10%, 20% and 30% proportion of coconut shell ash to
    partially replace the quantity of cement. The ratio of the interlocking pavement apply
    in this research is 1:2 which stand for one part cement and two part of sand. The
    findings withdrawn from this research are: first, the chemical characteristic of the
    coconut shell ash and cement. Second, the value of bulk density slightly reduces as the
    percentage of coconut shell ash increases. Third, the additional of coconut shell ash to
    partially replace the quantity of cement in the product reduce the compressive
    strength and increase the percentage of water absorption.
    Matched MeSH terms: Water
  4. Khoo LS, Lai PS, Saidin MH, Noor Z, Mahmood MS
    Forensic Sci Int, 2018 Jul;288:242-255.
    PMID: 29783180 DOI: 10.1016/j.forsciint.2018.04.017
    Cadaver body bags are the conventional method to contain a human body or human remains, which includes the use for storage and transportation of the deceased at any crime scene or disaster scene. During disasters, most often than not, the first responders including the police will be equipped with cadaver body bags to do scene processing of human remains and collection of personal belongings at the disaster site. However, in an unanticipated large scale disasters involving hundreds and thousands of fatalities, cadaver body bags supplies may be scarce. The authors have therefore innovated the cling film plastic wrap as an alternative for the cadaver body bag used at the disaster site. The plastic wrap was tested on six different experimental subjects, i.e. both adult and child mannequins; body parts of the mannequin figure (arm and hand); a human adult subject and an unknown dead body. The strengths of the cling film plastic wrap are discussed in comparison with the cadaver body bag in the aspects of costing, weight, duration of the wrap, water and body fluid resistant properties, visibility and other advantages. An average savings of more than 5000% are noted for both adult body wrap and child body wrap compared to the cadaver body wrap. This simply means that the authors can either wrap 25 adult dead bodies or 80 children dead bodies with the cost of 1 cadaver body bag. The cling film plastic wrap has proven to have significant innovation impact for dead body management particularly by the first responders in large scale disasters. With proper handling of dead bodies, first responders can manage the dead with dignity and respect in an overwhelmed situation to facilitate the humanitarian victim identification process later.
    Matched MeSH terms: Water
  5. Babiker, F., Jamal, P., Mirghani, M.E.S., Ansari, A.H.
    MyJurnal
    This study aimed at investigating the presence of alkaloids and other chemical constituents in Datura stramonium (Saikaran, Jimson weed). All parts of the plant were dried, crushed and then underwent extraction by soxhlet and maceration methods. The solvents used in these methods were normal hexane (nonpolar) and ethanol (polar). Thin Layer Chromatography (TLC) and FTIR techniques were used to analyse the chemical components of jimson weed. The results showed the presence of hyoscine in all plant parts while atropine in the seeds only. The best separation was found to be when the solvent system was acetone: water: ammonia (90:07:03). Maceration method is the best and cost effective procedure for extraction.
    Matched MeSH terms: Water
  6. Lee MK, Li X, Yap ACS, Cheung PCK, Tan CS, Ng ST, et al.
    Front Pharmacol, 2018;9:461.
    PMID: 29867469 DOI: 10.3389/fphar.2018.00461
    Lignosus rhinocerotis has a long history of use by the indigenous community within East Asia to treat a range of health conditions including asthma and chronic cough. To date, there is limited scientific evidence to support its therapeutic effects in relieving these airways conditions. In this study, we examined the effects of the different molecular weight fractions [high-molecular-weight (HMW), medium-molecular-weight (MMW), and low-molecular-weight (LMW)] obtained from the cold water sclerotial extract (CWE) of L. rhinocerotis on airways patency using airway segments isolated from Sprague Dawley rat in an organ bath set-up. It is demonstrated that the HMW and MMW fractions exhibited higher efficacy in relaxing the pre-contracted airways when compared to the CWE and LMW fraction. In addition, the HMW fraction markedly supressed carbachol-, 5-hydroxytrptamine-, and calcium-induced airway contractions. CWE demonstrated a lower efficacy than the HMW fraction but it also significantly attenuated carbachol- and calcium-induced airway contractions. Results showed that the bronchorelaxation effect of CWE and fractions is mediated via blockade of extracellular Ca2+ influx. The composition analysis revealed the following parts of carbohydrate and proteins, respectively: HMW fraction: 71 and 4%; MMW fraction: 35 and 1%; and LMW fraction: 22 and 0.3%. Our results strongly suggest that the polysaccharide-protein complex or proteins found in the HMW and MMW fractions is likely to contribute to the bronchorelaxation effect of CWE.
    Matched MeSH terms: Water
  7. Mohd NI, Zain NNM, Raoov M, Mohamad S
    R Soc Open Sci, 2018 Apr;5(4):171500.
    PMID: 29765632 DOI: 10.1098/rsos.171500
    A new cloud point methodology was successfully used for the extraction of carcinogenic pesticides in milk samples as a prior step to their determination by spectrophotometry. In this work, non-ionic silicone surfactant, also known as 3-(3-hydroxypropyl-heptatrimethylxyloxane), was chosen as a green extraction solvent because of its structure and properties. The effect of different parameters, such as the type of surfactant, concentration and volume of surfactant, pH, salt, temperature, incubation time and water content on the cloud point extraction of carcinogenic pesticides such as atrazine and propazine, was studied in detail and a set of optimum conditions was established. A good correlation coefficient (R2 ) in the range of 0.991-0.997 for all calibration curves was obtained. The limit of detection was 1.06 µg l-1 (atrazine) and 1.22 µg l-1 (propazine), and the limit of quantitation was 3.54 µg l-1 (atrazine) and 4.07 µg l-1 (propazine). Satisfactory recoveries in the range of 81-108% were determined in milk samples at 5 and 1000 µg l-1, respectively, with low relative standard deviation, n = 3 of 0.301-7.45% in milk matrices. The proposed method is very convenient, rapid, cost-effective and environmentally friendly for food analysis.
    Matched MeSH terms: Water
  8. Sharif Hossain ABM, Uddin MM, Fawzi M, Veettil VN
    Data Brief, 2018 Apr;17:1245-1252.
    PMID: 29845096 DOI: 10.1016/j.dib.2018.02.053
    The nano-cellulose derived nano-biofilm keeps a magnificent role in medical, biomedical, bioengineering and pharmaceutical industries. Plant biomaterial is naturally organic and biodegradable. This study has been highlighted as one of the strategy introducing biomass based nano-bioplastic (nanobiofilm) to solve dependency on petroleum and environment pollution because of non-degradable plastic. The data study was carried out to investigate the nano-biopolymer (nanocellulose) based nano-biofilm data from corn leaf biomass coming after bioprocess technology without chemicals. Corn leaf biomass was used to produce biodegradable nano-bioplastic for medical and biomedical and other industrial uses. Data on water absorption, odor, pH, cellulose content, shape and firmness, color coating and tensile strength test have been exhibited under standardization of ASTM (American standard for testing and materials). Moreover, the chemical elements of nanobiofilm like K+, CO3--, Cl-, Na+ showed standard data using the EN (166).
    Matched MeSH terms: Water
  9. Tan, Chin Yong, Galaz, German Bueno, Shapawi, Rossita
    MyJurnal
    This study was conducted to investigate the effects of dietary inclusion of Spirulina platensis on growth performance and hematological parameters of juvenile Asian sea bass (Lates calcarifer) reared in a freshwater culture system. Five experimental diets were prepared by replacing fish meal protein with the microalga at replacement levels of 5% (SP5), 10% (SP10), 20% (SP20) and 30% (SP30), and the substitution effect was compared with a control diet (Con) in which fish meal was the sole protein. Fish were stocked in net cages placed in a 150-ton tank with a stocking density of 20 fish per cage. After 8 weeks of feeding trial, the fish did not show any significant differences in growth performance but numerically higher weight gain and specific growth rate were achieved in the fish stock fed diet SP10 compared to other treatments. Feed conversion ratio and survival rate of fish were significantly affected by the inclusion of Spirulina in the diets. Except for crude ash content, whole-body proximate composition of the experimental fish was also significantly influenced by the diets. Regarding the effects of diets on blood parameters, only hematocrit, hemaglobin, HDL-c and AST were significantly affected by the inclusion of Spirulina in the diets. This study demonstrated that Spirulina could replace up to 10% of FM protein in practical diets of juvenile Asian sea bass without negative effects on growth performance. However, replacement of fish meal with Spirulina meal at 5% might be considered for commercial use considering a significant decrease in survival above this value.
    Matched MeSH terms: Fresh Water
  10. Sharif Hossain ABM, Uddin MM, Veettil VN, Fawzi M
    Data Brief, 2018 Apr;17:162-168.
    PMID: 29877503 DOI: 10.1016/j.dib.2017.12.046
    The nanocellulose derived biodegradable plant biomaterial as nano-coating can be used in the medical, biomedical cosmetics, and bioengineering products. Bio-plastic and some synthetic derived materials are edible and naturally biodegradable. The study was conducted to investigate edible nano-biopolymer based nano-coating of capsules and drugs or other definite biomedical materials from corn leaf biomass. Corn leaf biomass was used as an innovative sample to produce edible nano-coating bioplastic for drug and capsule coating and other industrial uses. The data show the negligible water 0.01% absorbed by bio-plastic nanocoating. Odor represented by burning test was under the completely standard based on ASTM. Moreover, data on color coating, tensile strength, pH, cellulose content have been shown under standard value of ASTM (American standard for testing and materials) standard. In addition to that data on the chemical element test like K+,


    CO


    3


    -
    -


    , Cl-, Na+ exhibited positive data compared to the synthetic plastic in the laboratory using the EN (166)) standardization. Therefore, it can be concluded that both organic (cellulose and starch) based edible nano-coating bioplastic may be used for drug and capsule coating as biomedical and medical components in the pharmaceutical industries.
    Matched MeSH terms: Water
  11. Bilad MR, Azizo AS, Wirzal MDH, Jia Jia L, Putra ZA, Nordin NAHM, et al.
    J Environ Manage, 2018 Oct 01;223:23-28.
    PMID: 29885561 DOI: 10.1016/j.jenvman.2018.06.007
    Microalgae technology, if managed properly, has promising roles in solving food-water-energy nexus. The Achilles' heel is, however, to lower the costs associated with cultivation and harvesting. As a favorable technique, application of membrane process is strongly limited by membrane fouling. This study evaluates performance of nylon 6,6 nanofiber membrane (NFM) to a conventional polyvinylidene fluoride phase inverted membrane (PVDF PIM) for filtration of Chlorella vulgaris. Results show that nylon 6,6 NFM is superhydrophilic, has higher size of pore opening (0.22 vs 0.18 μm) and higher surface pore density (23 vs 18 pores/μm2) leading to higher permeance (1018 vs 493 L/m2hbar) and better fouling resistant. Such advantages help to outperform the filterability of PVDF PIM by showing much higher steady-state permeance (286 vs 120 L/m2hbar), with comparable biomass retention. In addition, unlike for PVDF PIM, imposing longer relaxation cycles further enhances the performance of the NFM (i.e., 178 L/m2hbar for 0.5 min and 236 L/m2hbar for 5 min). Overall findings confirm the advantages of nylon 6,6 NFM over the PVDF PIM. Such advantages can help to reduce required membrane area and specific aeration demand by enabling higher flux and lowering aeration rate. Nevertheless, developments of nylon 6,6 NFM material with respect to its intrinsic properties, mechanical strength and operational conditions of the panel can still be explored to enhance its competitiveness as a promising fouling resistant membrane material for microalgae filtration.
    Matched MeSH terms: Water Purification
  12. Eweis AH, Yap AU, Yahya NA
    J Mech Behav Biomed Mater, 2017 10;74:183-188.
    PMID: 28605721 DOI: 10.1016/j.jmbbm.2017.06.004
    This study investigated the effect of food simulating liquids on visco-elastic properties of bulk-fill restoratives using dynamic mechanical analysis. One conventional composite (Filtek Z350 [FZ]), two bulk-fill composites (Filtek Bulk-fill [FB] and Tetric N Ceram [TN]) and a bulk-fill giomer (Beautifil-Bulk Restorative [BB]) were evaluated. Specimens (12 × 2 × 2mm) were fabricated using customized stainless steel molds. The specimens were light-cured, removed from their molds, finished, measured and randomly divided into six groups. The groups (n = 10) were conditioned in the following mediums for 7 days at 37°C: air (control), artificial saliva (SAGF), distilled water, 0.02N citric acid, heptane, 50% ethanol-water solution. Specimens were assessed using dynamic mechanical testing in flexural three-point bending mode and their respective mediums at 37°C and a frequency range of 0.1-10Hz. The distance between the supports were fixed at 10mm and an axial load of 5N was employed. Data for elastic modulus, viscous modulus and loss tangent were subjected to ANOVA/Tukey's tests at significance level p < 0.05. Significant differences in visco-elastic properties were observed between materials and mediums. Apart from bulk-fill giomer, elastic modulus was the highest after conditioning in heptane. No apparent trends were noted for viscous modulus. Generally, loss tangent was the highest after conditioning in ethanol. The effect of food-simulating liquids on the visco-elastic properties of bulk-fill composites was material and medium dependent.
    Matched MeSH terms: Water
  13. Matsuguma Y, Takada H, Kumata H, Kanke H, Sakurai S, Suzuki T, et al.
    Arch Environ Contam Toxicol, 2017 Aug;73(2):230-239.
    PMID: 28534067 DOI: 10.1007/s00244-017-0414-9
    Microplastics (<5 mm) were extracted from sediment cores collected in Japan, Thailand, Malaysia, and South Africa by density separation after hydrogen peroxide treatment to remove biofilms were and identified using FTIR. Carbonyl and vinyl indices were used to avoid counting biopolymers as plastics. Microplastics composed of variety of polymers, including polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethyleneterphthalates (PET), polyethylene-polypropylene copolymer (PEP), and polyacrylates (PAK), were identified in the sediment. We measured microplastics between 315 µm and 5 mm, most of which were in the range 315 µm-1 mm. The abundance of microplastics in surface sediment varied from 100 pieces/kg-dry sediment in a core collected in the Gulf of Thailand to 1900 pieces/kg-dry sediment in a core collected in a canal in Tokyo Bay. A far higher stock of PE and PP composed microplastics in sediment compared with surface water samples collected in a canal in Tokyo Bay suggests that sediment is an important sink for microplastics. In dated sediment cores from Japan, microplastic pollution started in 1950s, and their abundance increased markedly toward the surface layer (i.e., 2000s). In all sediment cores from Japan, Thailand, Malaysia, and South Africa, the abundance of microplastics increased toward the surface, suggesting the global occurrence of and an increase in microplastic pollution over time.
    Matched MeSH terms: Water
  14. Maiangwa J, Mohamad Ali MS, Salleh AB, Rahman RNZRA, Normi YM, Mohd Shariff F, et al.
    PeerJ, 2017;5:e3341.
    PMID: 28533982 DOI: 10.7717/peerj.3341
    The dynamics and conformational landscape of proteins in organic solvents are events of potential interest in nonaqueous process catalysis. Conformational changes, folding transitions, and stability often correspond to structural rearrangements that alter contacts between solvent molecules and amino acid residues. However, in nonaqueous enzymology, organic solvents limit stability and further application of proteins. In the present study, molecular dynamics (MD) of a thermostable Geobacillus zalihae T1 lipase was performed in different chain length polar organic solvents (methanol, ethanol, propanol, butanol, and pentanol) and water mixture systems to a concentration of 50%. On the basis of the MD results, the structural deviations of the backbone atoms elucidated the dynamic effects of water/organic solvent mixtures on the equilibrium state of the protein simulations in decreasing solvent polarity. The results show that the solvent mixture gives rise to deviations in enzyme structure from the native one simulated in water. The drop in the flexibility in H2O, MtOH, EtOH and PrOH simulation mixtures shows that greater motions of residues were influenced in BtOH and PtOH simulation mixtures. Comparing the root mean square fluctuations value with the accessible solvent area (SASA) for every residue showed an almost correspondingly high SASA value of residues to high flexibility and low SASA value to low flexibility. The study further revealed that the organic solvents influenced the formation of more hydrogen bonds in MtOH, EtOH and PrOH and thus, it is assumed that increased intraprotein hydrogen bonding is ultimately correlated to the stability of the protein. However, the solvent accessibility analysis showed that in all solvent systems, hydrophobic residues were exposed and polar residues tended to be buried away from the solvent. Distance variation of the tetrahedral intermediate packing of the active pocket was not conserved in organic solvent systems, which could lead to weaknesses in the catalytic H-bond network and most likely a drop in catalytic activity. The conformational variation of the lid domain caused by the solvent molecules influenced its gradual opening. Formation of additional hydrogen bonds and hydrophobic interactions indicates that the contribution of the cooperative network of interactions could retain the stability of the protein in some solvent systems. Time-correlated atomic motions were used to characterize the correlations between the motions of the atoms from atomic coordinates. The resulting cross-correlation map revealed that the organic solvent mixtures performed functional, concerted, correlated motions in regions of residues of the lid domain to other residues. These observations suggest that varying lengths of polar organic solvents play a significant role in introducing dynamic conformational diversity in proteins in a decreasing order of polarity.
    Matched MeSH terms: Water
  15. Tan SA, Goya L, Ramanathan S, Sulaiman SF, Alam M, Navaratnam V
    Food Res Int, 2014 Oct;64:387-395.
    PMID: 30011665 DOI: 10.1016/j.foodres.2014.06.040
    Extract from papaya leaves, a waste material from fruit farms in Malaysia was previously reported to possess remarkable antioxidative activities. In this study, papaya leaf extract was separated into fractions of different polarities [petroleum ether (PE), ethyl acetate (EA), n-butanol (NB) and water (W) fractions]. The aim of this research was to determine the most active fraction in terms of its chemopreventive effects towards oxidative stress and the chemical constituents involved. The cytoprotective nature of the papaya fractions was observed against t-BOOH-induced oxidative stress on HepG2 liver cell line. ROS assay indicated that only PE and EA effectively reduced the increment of radical due to the pro-oxidant, t-BOOH. Nevertheless, PE was a stronger ROS scavenger by demonstrating ROS reducing activity in a dose-dependent manner to the basal level. This fraction was also found to inhibit cell death caused by t-BOOH toxicity, attenuating lactate dehydrogenase enzyme leakage by more than 90% (p<0.05). In addition, gene expression of phase II antioxidant enzymes (hmox-1 and nqo-1) and their transcription factor (nrf-2) were shown to be upregulated upon PE treatment during a time-course study. A GC-MS fingerprint of the active fraction was subsequently obtained with standardization using the marker compound; α-tocopherol, a well known antioxidant. However, this pure compound was not as effective as its corresponding PE concentrations in ROS reduction. Hence, PE of papaya leaf extract was a strong antioxidant and cytoprotectant with tremendous potential to be harnessed into the next therapeutic remedy against oxidative stress of the liver.
    Matched MeSH terms: Water
  16. Thavamoney N, Sivanadian L, Tee LH, Khoo HE, Prasad KN, Kong KW
    J Food Sci Technol, 2018 Jul;55(7):2523-2532.
    PMID: 30042568 DOI: 10.1007/s13197-018-3170-6
    This study investigated the recovery of phytochemical antioxidants in Dacryodes rostrata fruit using different extraction solvents. The effects of solvent of varying polarities with sequential extraction method on the recovery of phenolics, flavonoids, carotenoids and anthocyanins from different parts of the fruit (seed, pulp and peel) were determined. Their antioxidant activities were further determined using DPPH radical, ferric reducing antioxidant power (FRAP), hydroxyl radical scavenging, superoxide anion radical scavenging and phosphomolybdenum method. Dacryodes Rostrata seed had the highest total phenolic content with 50% ethanol as the most efficient extraction solvent. The highest total flavonoid content was obtained in ethyl acetate extract of fruit pulp, whereas peel extracted with hexane and 50% ethanol was the highest in total carotenoid content and total anthocyanin content, respectively. The seed extracted with 50% ethanol exhibited the strongest DPPH radical scavenging activity. Iron chelating activity measured by FRAP assay was the best in seed extracts, particularly in those polar extracts derived from water and 50% ethanol. Antioxidant activities of 50% ethanol extract of D. rostrata seed was the highest when determined by FRAP and phosphomolydenum assays. However, the influence of extraction solvents is not distinctly shown by hydroxyl radical and superoxide anion radical scavenging activities. This is the first report on the effect of various extraction solvents on the recovery of phytochemicals in D. rostrata fruit parts and the seed of D. rostrata is a potential source of polar antioxidants.
    Matched MeSH terms: Water
  17. Faizalhakim, A.S., Nurhidayu, S., Norizah, K.
    MyJurnal
    Rainfall-runoff information is critical for water resource and river basin management. Runoff can be estimated by using two methods; gauged method (direct measurement) and ungauged method (indirect formula and equation). The in-situ measurement provides real-time and accurate yet required time-consuming operation and inaccessibility topography. Therefore, the runoff estimation modelling and equation was developed to overcome the limitation of in-situ measurement. SCS-CN is a simple model of ungauged method, where runoff volume (Q) resulting from rainfall (P) is formulated using equation of (Q= (P-Ia) 2 / (P-Ia + S). It was known as the best technique to be adopted for large basin study where time and manpower also accessibility are limited. SCS-CN method also is widely use in prediction software as it taken into consideration of the effects of soil, properties, land cover and antecedent moisture. Curve Number is well developed in USA for the agriculture purpose with many investigations to validate and calibrate the values of curve number. It was applied in numerous river basins in temperate and other regions e.g. US, Argentina, India, China, South Korea, Palestine and Malaysia. However, the reliability of the CN in the tropics is doubtable due to different land use characteristics, soil type, climate, geological features and rainfall pattern and variability. Based on the reviewed conceptual and applications of SCS-CN in temperate and tropics, numerous studies found the SCS-CN method is reliable and practical for runoff estimation in tropics region.
    Matched MeSH terms: Water Resources
  18. 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 
    Matched MeSH terms: Water Pollutants, Chemical
  19. Nor Azman, A.R., Saub, R., Raja Latifah, R.J.
    Malaysian Dental Journal, 2015;37(1):24-29.
    MyJurnal
    This study was conducted on Royal Malaysian Navy submariners who were having training in France. It was designed to compare the oral health experiences and practices while under water and on land. Methods Eightysix Royal Malaysian Navy (RMN) submariners, who had undergone at least one cycle (288 hours) of under water training, were selected to participate in a self-administered questionnaire survey. Results Seven percent of the respondents reported oro-facial pain and discomfort; 9.3% reported bleeding gums and 12.8% experienced halitosis while under water. Of those experience oral problems, 82% reported disruption of their daily activities while under water. The study showed that 82.5% of them brush their teeth at least twice a day and 94.2% rinse after meals when there were under water. Meanwhile studies on land showed that 90.7% of them brush their teeth at least twice a day and 96.5% rinse after meals. Flossing was not practiced by most of the respondents. Conclusion It is concluded that brushing and rinsing are practiced regularly by submariners regardless whether they are on land or under water but flossing is not a common practice both on land and under water. Dental emergencies, such as toothache, TMJ pain and discomfort do occur during submarine operations and disrupt their daily activities. This might poses a threat to submarine operations.
    Matched MeSH terms: Water
  20. Ang TF, Salleh AB, Normi YM, Leow TC
    3 Biotech, 2018 Jul;8(7):314.
    PMID: 30023146 DOI: 10.1007/s13205-018-1333-9
    Artificial metalloenzymes are unique as they combine the good features of homogeneous and enzymatic catalysts, and they can potentially improve some difficult catalytic assays. This study reports a method that can be used to create an artificial metal-binding site prior to proving it to be functional in a wet lab. Haloalkane dehalogenase was grafted into a metal-binding site to form an artificial metallo-haloalkane dehalogenase and was studied for its potential functionalities in silico. Computational protocols regarding dynamic metal docking were studied using native metalloenzymes and functional artificial metalloenzymes. Using YASARA Structure, a simulation box covering template structure was created to be filled with water molecules followed by one mutated water molecule closest to the metal-binding site to metal ion. A simple energy minimization step was subsequently run using an AMBER force field to allow the metal ion to interact with the metal-binding residues. Long molecular dynamic simulation using YASARA Structure was performed to analyze the stability of the metal-binding site and the distance between metal-binding residues. Metal ions fluctuating around 2.0 Å across a 20 ns simulation indicated a stable metal-binding site. Metal-binding energies were predicted using FoldX, with a native metalloenzyme (carbonic anhydrase) scoring 18.0 kcal/mol and the best mutant model (C1a) scoring 16.4 kcal/mol. Analysis of the metal-binding site geometry was performed using CheckMyMetal, and all scores for the metalloenzymes and mutant models were in an acceptable range. Like native metalloenzymes, the metal-binding site of C1a was supported by residues in the second coordination shell to maintain a more coordinated metal-binding site. Short-chain multihalogenated alkanes (1,2-dibromoethane and 1,2,3-trichloropropane) were able to dock in the active site of C1a. The halides of the substrate were in contact with both the metal and halide-stabilizing residues, thus indicating a better stabilization of the substrate. The simple catalytic mechanism proposed is that the metal ion interacted with halogen and polarized the carbon-halogen bond, thus making the alpha carbon susceptible to attack by nucleophilic hydroxide. The interaction between halogen in the metal ion and halide-stabilizing residues may help to improve the stabilization of the substrate-enzyme complex and reduce the activation energy. This study reports a modified dynamic metal-docking protocol and validation tests to verify the metal-binding site. These approaches can be applied to design different kinds of artificial metalloenzymes or metal-binding sites.
    Matched MeSH terms: Water
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