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Heavy Metals Leaching Behaviour Assessment of Palm Oil Clinker
No full textTechnical benefit of incorporation of Palm Oil Clinker (POC) in cement-based applications has been proven in recent studies. The aim of this work was to assess the heavy metal leaching behavior to ensure environmental safety of using POC in cement-based applications. The chemical composition, morphology, total organic carbon (TOC) and mineralogy were determined using XRF, FESEM, TOC analyzers and XRD to select appropriate chemical reagents for complete digestion. HNO3, HF and HClO4 were used for digestion of POC to measure heavy metal content using ICP-MS. The chemical reagents CH3COOH, NH2OH-HCl, H2O2+CH3COONH4 and HF+HNO3+HCl were used for extraction of acid soluble, reducible, oxidizable and residual fractions of heavy metals in POC, respectively. The leaching toxicity of the POC was investigated by the USEPA 1311 TCLP method. The result showed the presence of Be, V, Cr, Ni, Cu, Zn, As, Se, Ag, Cd, Ba and Pb with levels of 5.13, 11.02, 2.65, 1.93, 45.43, 11.84, 15.07, 0, 0, 81.97 and 1.76 mg/kg, respectively, in POC. The leaching value in mg/L of As (4.56), Cu(1.05), Be (0.89), Zn(0.51), Ba(0.26), Ni (0.17), V(0.15), Cr(0.001) and Se (0.001) is found well below the standard limit of risk. Risk assessment code (RAC) analysis confirms the safe incorporation of POC in cement-based applications
Public opinion on renewable energy technologies and climate change in Peninsular Malaysia
No full textThe development of renewable energy policies is necessary to ensure secure and sustainable energy supplies at reasonable costs and to address issues related to global climate change. Since the year 2000 in Malaysia (time of the 8th Malaysian Plan), renewable energy has been included as a key fifth element in the country's fuel policy along with hydro, coal, gas, and oil, and a target of obtaining 5% of the total energy supply from renewable sources was set, although it has not yet been reached. This work explores public opinions regarding climate change and renewable energy in Peninsular Malaysia. Probability sampling and a stratified technique were used to conduct a survey with subjects aged 20 years and over with higher education qualifications. The results showed that the majority of Malaysians are concerned about climate change and have heard about renewable energy. However, only two out of five people in Peninsular Malaysia have used renewable energy products. This finding can be explained by the high price of renewable energy products, lack of knowledge about government policies, and ineffective programs and initiatives
Developing Facilities Management (FM) competencies for Malaysia: reference from international practice
No full textPurpose: The purpose of this paper is to investigate the significance of facilities management (FM) competency levels from three different stages, namely, strategic, tactical and operational levels, to propose a set of FM competencies for an enhanced FM industry in Malaysia. Design/methodology/approach: The overall focus for this paper is to discuss on the area for each level of competencies for asset and facilities management (AFM). This is done through a questionnaire survey focusing on the competency areas posed by FM companies in Malaysia and a comparison review of all FM levels as outlined by the international professional bodies, namely, International Facility Management Association, British Institute of Facilities Management and Royal Institute of Chartered Surveyors. This paper also looks at formulating a holistic framework for an effective AFM for the benefit of FM industry in general and Malaysian FM industry specifically. Findings: The findings indicate that among the significant factors for the respective strategic, tactical and operational practice of FM are strategic: managing change, benchmarking and strategic facilities planning; tactical: risk management, emergency preparedness, FM technology, service-level agreement and supply management; and operational: space planning and management. This study also proposes a set of holistic FM competency areas which can be implemented by the FM industry in Malaysia. Originality/value: This research sets a baseline for a set of FM competencies, an area of FM which has not been regulated in the FM practice in Malaysia
Development Framework for Agro-Based Industries in Secondary Cities of Sindh Province, Pakistan: SWOT Analysis of Ten-Year Perspective and Medium-Term Development Framework Plans
No full textThe study intended to explore planning strategies gaps in ten-year perspective and medium-term development framework plans for agro-based industrial development in secondary cities of Sindh Province, Pakistan. Document review and key informant interviews survey techniques were used for data collection. A total of 30 interviews were conducted from agro-based officials. The SWOT analysis technique was applied for data analysis. The results revealed the weaknesses of high priority for textile and sugar industries, lack of planning strategies for agro-based development in secondary cities, dependency on federal government for development funds and absence of finances to implement plans. The threats were unavailability of strategic agro-based infrastructure facilities in secondary cities, centralized planning system, cross border threats such as the war in Afghanistan and migration of Afghan refugees, weak law and order situation and diversion of development budget for defense activities. The study suggests decentralization of powers and robust planning strategies in the development plans to strengthen secondary cities of Sindh Province economically
Microarray gene expression profiling in colorectal (HCT116) and hepatocellular (HepG2) carcinoma cell lines treated with Melicope ptelefolia leaf extract reveals transcriptome profiles exhibiting anticancer activity
No full textBackground. We have previously reported anticancer activities of Melicope ptelefolia (MP) leaf extracts on four different cancer cell lines. However, the underlying mechanisms of actions have yet to be deciphered. In the present study, the anticancer activity of MP hexane extract (MP-HX) on colorectal (HCT116) and hepatocellular carcinoma (HepG2) cell lines was characterized through microarray gene expression profiling. Methods. HCT116 and HepG2 cells were treated with MP-HX for 24 hr. Total RNA was extracted from the cells and used for transcriptome profiling using Applied Biosystem GeneChipTM Human Gene 2.0 ST Array. Gene expression data was analysed using an Applied Biosystems Expression Console and Transcriptome Analysis Console software. Pathway enrichment analyses was performed using Ingenuity Pathway Analysis (IPA) software. The microarray data was validated by profiling the expression of 17 genes through quantitative reverse transcription PCR (RT-qPCR). Results. MP-HX induced differential expression of 1,290 and 1,325 genes in HCT116 and HepG2 cells, respectively (microarray data fold change, MA_FC ≥ ±2.0). The direction of gene expression change for the 17 genes assayed through RT-qPCR agree with the microarray data. In both cell lines, MP-HX modulated the expression of many genes in directions that support antiproliferative activity. IPA software analyses revealed MP-HX modulated canonical pathways, networks and biological processes that are as- sociated with cell cycle, DNA replication, cellular growth and cell proliferation. In both cell lines, upregulation of genes which promote apoptosis, cell cycle arrest and growth inhibition were observed, while genes that are typically overexpressed in diverse human cancers or those that promoted cell cycle progression, DNA replication and cellular proliferation were downregulated. Some of the genes upregulated by MP-HX include pro-apoptotic genes (DDIT3, BBC3, JUN), cell cycle arresting (CDKN1A, CDKN2B), growth arrest/repair (TP53, GADD45A) and metastasis suppression (NDRG1). MP-HX downregulated the expression of genes that could promote anti-apoptotic effect, cell cycle progression, tumor development and progression, which include BIRC5, CCNA2, CCNB1, CCNB2, CCNE2, CDK1/2/6, GINS2, HELLS, MCM2/10 PLK1, RRM2 and SKP2. It is interesting to note that all six top-ranked genes proposed to be cancer- associated (PLK1, MCM2, MCM3, MCM7, MCM10 and SKP2) were downregulated by MP-HX in both cell lines. Discussion. The present study showed that the anticancer activities of MP-HX are exerted through its actions on genes regulating apoptosis, cell proliferation, DNA replication and cell cycle progression. These findings further project the potential use of MP as a nutraceutical agent for cancer therapeutics
Comparative genomic analysis of ten clinical Streptococcus pneumoniae collected from a Malaysian hospital reveal 31 new unique drug-resistant SNPs using whole genome sequencing
No full textBackground: Streptococcus pneumoniae or pneumococcus is a leading cause of morbidity and mortality worldwide, specifically in relation to community-acquired pneumonia. Due to the overuse of antibiotics, S. pneumoniae has developed a high degree of resistance to a wide range of antibacterial drugs. Methods: In this study, whole genome sequencing (WGS) was performed for 10 clinical strains of S. pneumoniae with different levels of sensitivity to standard antibiotics. The main objective was to investigate genetic changes associated with antibiotic resistance in S. pneumoniae. Results: Our results showed that resistant isolates contain a higher number of non-synonymous single nucleotide polymorphisms (SNPs) as compared to susceptible isolates. We were able to identify SNPs that alter a single amino acid in many genes involved in virulence and capsular polysaccharide synthesis. In addition, 90 SNPs were only presented in the resistant isolates, and 31 SNPs were unique and had not been previously reported, suggesting that these unique SNPs could play a key role in altering the level of resistance to different antibiotics. Conclusion: Whole genome sequencing is a powerful tool for comparing the full genome of multiple isolates, especially those closely related, and for analysing the variations found within antibiotic resistance genes that lead to differences in antibiotic sensitivity. We were able to identify specific mutations within virulence genes related to resistant isolates. These findings could provide insights into understanding the role of single nucleotide mutants in conferring drug resistance
Soil erosion assessment on hillslope of GCE using RUSLE model
No full textA new method for obtaining the C factor (i.e., vegetation cover and management factor) of the RUSLE model is proposed. The method focuses on the derivation of the C factor based on the vegetation density to obtain a more reliable erosion prediction. Soil erosion that occurs on the hillslope along the highway is one of the major problems in Malaysia, which is exposed to a relatively high amount of annual rainfall due to the two different monsoon seasons. As vegetation cover is one of the important factors in the RUSLE model, a new method that accounts for a vegetation density is proposed in this study. A hillslope near the Guthrie Corridor Expressway (GCE), Malaysia, is chosen as an experimental site whereby eight square plots with the size of 8 × 8 and 5 × 5 m are set up. A vegetation density available on these plots is measured by analyzing the taken image followed by linking the C factor with the measured vegetation density using several established formulas. Finally, erosion prediction is computed based on the RUSLE model in the Geographical Information System (GIS) platform. The C factor obtained by the proposed method is compared with that of the soil erosion guideline Malaysia, thereby predicted erosion is determined by both the C values. Result shows that the C value from the proposed method varies from 0.0162 to 0.125, which is lower compared to the C value from the soil erosion guideline, i.e., 0.8. Meanwhile predicted erosion computed from the proposed C value is between 0.410 and 3.925tha-1yr-1 compared to 9.367 to 34.496tha-1yr-1 range based on the C value of 0.8. It can be concluded that the proposed method of obtaining a reasonable C value is acceptable as the computed predicted erosion is found to be classified as a very low zone, i.e. less than 10tha-1yr-1 whereas the predicted erosion based on the guideline has classified the study area as a low zone of erosion, i.e., between 10 and 50tha-1yr-1
Performance Evaluation of Maximum Power Point Tracking Approaches and Photovoltaic Systems
No full textThis paper elaborates a comprehensive overview of a photovoltaic (PV) system model, and compares the attributes of various conventional and improved incremental conductance algorithms, perturbation and observation techniques, and other maximum power point tracking (MPPT) algorithms in normal and partial shading conditions. Performance evaluation techniques are discussed on the basis of the dynamic parameters of the PV system. Following a discussion of the MPPT algorithms in each category, a table is drawn to summarize their key specifications. In the performance evaluation section, the appropriate PV module technologies, atmospheric effects on PV panels, design complexity, and number of sensors and internal parameters of the PV system are outlined. In the last phase, a comparative table presents performance-evaluating parameters of MPPT design criterion. This paper is organized in such a way that future researchers and engineers can select an appropriate MPPT scheme without complication
Evaluation of Solvent-Free Microwave Extraction Conditions on Essential Oils from Allium cepa Through Chemometric Analysis
No full textBackground: The feasibility of applying methods or the extraction of Allium cepa essential oils using solvent-free microwave extraction (SFME) has been compared to hydro-distillation (HD) process. Parameters of extraction were investigated using a rational design of experiment screening. Objective: To screen the important factors that may influence the quantity and/or quality of the extracts derived from Allium cepa Method: A no. of 13 experiments were performed based on the screening process. The key parameters, such as power (350/500 W), size of the sample (chopped/sliced), quantity (500/1000 g), time of extraction (25/50 min.) and water ratio (20/50 mL) were selected based on the limitation of the instrument. The essential oils derived from Allium cepa were characterized by GC-MS analysis. Results: The commonly collected constituents via SFME and HD are 3,4-Dimethylthiophene, Disul-fide, methyl propyl, Dithiolane, 2,4-Dimethyl-5,6-dithia-2,7-nonadienal, 4,6-Diethyl-1,2,3,5-tetrathiolane, 5,7-Diethyl-1,2,3,4,6-pentathiepane (sulfur-containing compounds) and Methoxyacetic acid, cyclopentyl ester, 2-Propenoic acid, 2-methyl-, octyl ester (fatty acid esters). Conclusion: A pragmatic relationship between the variations of extraction parameters has been studied. Results suggested and verified that among the factors, Power and time of extraction influence the process of extraction significantly
Sucrose enhanced stigmasterol production in callus cultures of Wedelia biflora (L.) D.C
No full textCallus culture method was used to extract stigmasterol in mass amount. The current study aims to enhance the production of stigmasterol by manipulation of sucrose concentrations in Murashige and Skoog (MS) media. A combination of 2 mg NAA L-1 (an auxin) and 2.5 mg 6-benzylaminopurine (BAP) L-1 (a cytokinin) in MS medium was the best concentration to stimulate callus formation from stem explants of W. biflora with the fastest response (10 d), the highest biomass of callus (55 mg dry weight) and the best callus characteristic (green and compact). Application of 4% (w/v) sucrose in MS medium enhanced callus formation along with callus biomass and stigmasterol production (88 mg g-1) compared with the control (58.3 mg g-1) and in vivo grown stem (53.4 mg g-1). Production of stigmasterol from W. biflora with reduced production time and cost is now possible with the methods obtained from the current study