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- PublicationIn silico development of dna aptamer-targeting breast cancer soluble pdl-1 (spdl-1) protein(2026-01)This study aimed to develop an aptamer-based bioassay, also known as enzyme-linked oligonucleotide assay (ELONA), for the detection of soluble programmed death-ligand 1 (sPD-L1) by integrating in-silico approaches with experimental validation. sPD-L1 is an important immune-related cancer biomarker; however, conventional antibody-based ELISA methods are limited by high cost, stability issues and batch-to-batch variability. In this work, multiple ssDNA aptamers were generated and systematically screened in- silico using secondary and three-dimensional structure prediction, molecular docking, protein–ligand interaction analysis and molecular dynamics simulations to identify a candidate with favourable binding affinity and complex stability toward PD-L1. The selected aptamer was subsequently validated experimentally using ELONA. The assay demonstrated concentration-dependent and saturable binding of the aptamer to immobilised PD-L1, with a moderate equilibrium dissociation constant (Kd), indicating functional and specific interaction. Overall, the findings confirm the feasibility of combining in-silico guided aptamer selection with experimental ELONA development and support the potential of aptamers as viable alternatives to antibodies in cancer biomarker detection.
- PublicationDetermination of heavy metals in powder and cream blushers from local cosmetic brands using atomic absorption spectroscopy (AAS)(2026-01)Heavy metals have been widely used in the manufacture of cosmetic products, including blusher, which mainly serve as colorants. However, higher concentrations of heavy metals could cause adverse health effects to the consumer such as kidney failure, liver dysfunction and skin irritation especially for long-term exposure. This study aims to analyse the concentration of heavy metals, lead (Pb), cadmium (Cd) and chromium (Cr) in the blusher samples which are powder-based blusher and cream-based blusher among the local brands products. Hence, two different types of formulations from three different local brands were randomly selected from local market. Each sample undergoes homogenisation and wet acid digestion process as the sample preparation procedure. The blusher samples were analysed using atomic absorption spectrophotometer (AAS) in order to determine the concentration of heavy metals in the sample. Due to inconsistency differences in concentration of heavy metals among powder and cream blusher, it prevents a clear comparison of the metal content. The data and results obtained from the study were compared to the established regulatory limit of heavy metals in cosmetic products as outlined by the Association of Southeast Asian Nations (ASEAN) and Malaysian National Pharmaceutical Regulatory Agency (NPRA). As the result, samples A, B, C, Y and Z displayed Pb concentration that above permissible limit, (Pb ≤10 ppm). Cd levels above the allowable limit (Cd ≤1 ppm) were observed among samples C, X and Z. Higher concentrations of Cr were observed in sample A, B, X and Z (Cr is banned). However, the authorities should closely monitor the manufacture of local cosmetic products as exceeding the standard permissible limit of heavy metals could cause adverse health effects to the consumers and may be charged under the Sale of Drugs Act 1952.
- PublicationDetermining the fly and maggot population based on different types of animal meat(2026-02)Necrophagous insects play a crucial role in forensic entomology, particularly in the estimation of post-mortem interval (PMI). Specifically, necrophagous flies have been the focus of relevant studies as they are the earliest colonizer of decomposing carcasses and cadavers. This study focuses on investigating the differences between the necrophagous fly species associated with different types of animal meat, which are pork, lamb, and beef. The experiment was conducted twice during rainy and non-rainy seasons to simultaneously examine the influence of environmental factors, including rainfall, ambient temperature, and humidity. A key finding was the distinct feeding preferences exhibited by Megaselia Scalaris (Diptera: Phoridae) and Sarcophaga sp. (Diptera: Sarcophagidae) exclusively towards beef, while Chrysomya Megacephala were observed to feed on all types of animal meats studied, and Chrysomya Rufifacies feeds on both pork and beef. Additionally, environmental factors played a key role in influencing the decomposition rate and the insect activity, which leads to delayed decomposition and the oviposition of necrophagous flies. However, the findings of this study were limited to identifying the difference in feeding preferences among necrophagous flies, while the underlying causes were yet to be determined.
- PublicationDetection of 9-BP deletion in coii/trnalys intergenic region of mitochondrial DNA among Melanau ethnic group(2026-02)Mitochondria are essential organelles in organism responsible for cellular energy production, which is necessary for metabolic reactions. It has its own genetic material called mitochondrial DNA (mtDNA) and has interesting features such as maternal inheritance, high mutation rate, high copy number and lack of recombination. MtDNA has been applied in forensic identification to solve forensic cases and is also used in population genetics studies. One of the mtDNA polymorphisms used in population genetics studies is located between cytochrome c oxidase II (COII) and lysine tRNA (tRNALys) genes, consisting of the two copies of a 9-bp tandem repeat sequence (CCCCCTCTA). Deletion of on copy in this tandem is used as a characteristic for mtDNA haplogroup B. This study aimed to detect the presence of the 9-bp deletion in the COII/tRNALys intergenic region of mitochondrial DNA among Melanau individuals through PCR amplification and agarose gel electrophoresis. Genomic DNA was extracted from the whole blood samples and assessed for quality and quantity to ensure sufficient DNA for downstream analysis. PCR amplification of the target region was performed using primers 8215F and 8385R. The findings show that 24 Melanau individuals (20%) had 9-bp deletion, and this distribution is supported by the previous studies that 9-bp deletion is frequently observed in the population of mainland southeastern Asia, Island southeast Asia and Southwest Asian.
- PublicationDevelopment of latent fingermarks at extremely low temperature(2026-02)Fingermarks are a crucial form of forensic evidence due to their persistence and individuality. However, their stability can be affected by environmental exposure and substrate characteristics. Criminals may attempt to conceal evidence by subjecting it to extreme conditions such as freezing, making the recovery of usable fingermarks a significant forensic challenge due to residue degradation and condensation effects. This study investigated the development of latent fingermarks on various substrates, including food (apple and orange), five types of plastics (HDPE, PET, polypropylene, polystyrene and LDPE), metal and glass after exposure to −20°C in the freezer for one week. The study was conducted in two phases; a preliminary experiment to assess surface changes and identify effective development methods for fresh sebaceous fingermarks, and a main experiment to evaluate development performance after freezing. Eight development techniques were examined: non-magnetic powder, magnetic powder, SPR, Sudan Black, Amido Black, Crystal Violet, Oil Red O and ninhydrin. Sudan Black, Oil Red O and magnetic powder consistently showed higher effectiveness in the preliminary phase for most tested substrates. Results from the main experiment indicated that latent fingermarks could still be developed after being frozen at −20°C for one week. However, a general reduction in quality and ridge detail was observed. Fingermark quality was influenced by substrate type and development technique. Non-porous substrates such as plastic, metal and glass retained ridge detail longer than food substrates, which exhibited faster degradation due to higher moisture content. These findings provide valuable insight into the effects of extreme cold exposure on fingermark development and support the improvement of protocols for latent fingermark visualisation and preservation in cold or frozen environments.
Most viewed
- ItemPengurusan Krisis Dan Proses Membuat Pertimbangan (Sensemaking) Oleh Pengamal Perhubungan Awam Di Malaysia: Kajian Kes Krisis Halal Cadbury(Universiti Sains Malaysia, 2017-10)Objektif utama kajian ini adalah untuk memahami dan menerangkan proses sensemaking oleh pengamal perhubungan awam semasa krisis organisasi yang dicetuskan oleh media sosial termasuk tiga objektif khusus; (1) untuk mengenal pasti peranan pengamal perhubungan awam semasa krisis organisasi yang dicetuskan oleh media sosial (2) untuk memahami cara pengamal perhubungan awam memberi makna terhadap media sosial semasa krisis organisasi dan (3) untuk mengenal pasti kepentingan sensemaking dalam mempengaruhi Kitaran Perlakuan Komunikasi (Communication-behavior-cycle) semasa pengamal perhubungan awam mengendalikan krisis organisasi. Kajian ini mengaplikasikan kaedah kualitatif dengan reka bentuk kajian kes.
- PublicationOptimization Of Optical And Radar Satellite Data In Google Earth Engine For Monitoring Oil Palm Changes In Tropical River Basins(2023-09)Accurate mapping of oil palm plantations is crucial for planning agricultural best management practices. Google Earth Engine (GEE), a cloud-based computing platform, allowing users to process multi-source satellite images more quickly and effectively. In fact, it is difficult to distinguish oil palm from other crops using only optical satellites due to the issue of cloud cover in tropical regions. Unfortunately, there is only little scientific understanding about how various satellite images within GEE can be helpful for mapping oil palm plantations. Hence, this study aims to determine the optimal combination of open-source optical and radar satellite data for mapping oil palm plantations in tropical river basins using the Muda River Basin (MRB) and the Johor River Basin (JRB) as test sites. First, the two machine learning classifiers available in GEE, random forest (RF) and support vector machine (SVM), were compared to identify which is the most effective classifier for mapping oil palm plantations. Then, eight different data combinations have been constructed from the satellite images and indices such as C-band Sentinel-1, L-band PALSAR2, Landsat8, Sentinel-2, topographic, Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), etc. Lastly, the optimal data combination was employed to project future oil palm distribution using the CA-Markov approach. The findings demonstrate that RF outperformed SVM in mapping oil palm plantations in both river basins.
- ItemAnalysis of harmonics current minimization on power distribution system using voltage phase shifting concept(2007)Non linear loads such as switch mode power supply and adjustable speed drive in three phase three wires power distribution system can causes line current system distorted. The non linear loads on three phases three wires power distribution system were produced dominantly 5-th and 7-th order harmonic currents. Increasing of harmonics current on electric power distribution system leads to degradation of system performance. To reducing the harmonics current on power distribution system should be minimized the 5-th and 7-th order harmonics current components. The minimization process of harmonic current is accomplished by voltage phase angle shifting on the two branches of non-linear load system, where the different phase angle between both of branches should be300 . Because of 5-th order harmonic current component is negative sequence and 7-th order harmonic current component is positive sequence, therefore these harmonic current components on the line system are opposite each other. Base on this concept, the phase shifter designing to harmonic minimization is “Double Symmetric Zig-zag Autotransformer”. The experimentation results for harmonic current minimization in three phase three wires power distribution system using this voltage phase angle shifting concept. It shows that the total current harmonic distortion on the line current system can be reduced from 30.03 % become 10.2 %. This value is fulfill the IEEE standard 519-1992 recommended, where the IEEE standard 519-1992 allows the maximum limits for total current harmonic distortion containing in power distribution system is bellow than 20 %. The advantage of this concept is simply and practice, because it is only required electromagnetic circuit and does not require sensor and control and the electronic components. Beside this, The Double Symmetric Zig-zag Autotransformer harmonic reducer has low rating kVA, smaller size, low losses and higher efficiency.
- ItemSimulations For Steam Methane Reforming Over Ni/Al2O3 Catalyst In A Fixed Bed Reactor And A Membrane Reactor(Universiti Sains Malaysia, 2021-07-01)The limitations of steam methane reforming (SMR) process in fixed bed reactor (FBR) is thermodynamic equilibrium constraint and the requirement of high operating temperature. Membrane reactor (MR) have huge application potential for the equilibrium limited, endothermic SMR process due to the simultaneous withdrawal of reaction product, H2. The steady-state behavior of SMR process in FBR and MR are examined by developing a 1-D, pseudo-homogeneous mathematical modelling framework that operates at isothermal and isobaric mode. The calculation procedures was performed using MATLAB and both of the reactor models were validated against experimental data. Comparative SMR performance assessment in terms of methane conversion (XCH4, H2 yield and selectivity of CO (SCO) and CO2 (SCO2) between FBR and MR were accordingly conducted. The increasing temperature has positive impact on XCH4 and H2 yield, but at temperature above 650 ℃, the positive impact of H2 removal in MR becomes less significant compared to FBR. Besides, SCO2 and SCO are only affected by temperature in which increasing temperature promotes the reverse water gas shift reaction, resulting in the increase of SCO. For FBR, SCO exceeds SCO2 at around 590 ℃ while for MR, SCO exceeds SCO2 at around 610 ℃. Next, the effect of increasing reaction pressure show an opposite trend for MR and FBR, in MR, higher XCH4 is obtained when pressure increases due to the increase of H2 partial pressure driving force but in FBR, higher pressure is not favoured. In addition, methane inlet flow rate higher than 0.03 kmol/h suppressed the positive impact of H2 removal in MR while lower permeation zone pressure (Pperm) and higher sweep gas flow rate improve the reaction performance in MR.
- PublicationArtificial neural network for gas-oil flow pattern recognition using capacitance tomography data(2009-04-01)The technique to recognize the oil and gas flow pattern in a pipe is needed in the oil and gas industry to monitoring the condition of the oil and gas pipe system. Any mistake or malfunction may lead to serious loss and endanger the workers and environments. Generally there are lots of flow pattern such as Empty, Full, Stratified, Bubble, Core and Annular. The Electrical Capacitance Tomography (ECT) technique is used to take the cross sectional data of the pipe. The Artificial Neural Networks (ANNs) is used to recognize the flow patterns. This project uses the Multilayer Perceptron (MLP) as the ANNs model. The MLP is trained, validated, and tested with the ECT data. The ECT data is divided into three groups, training, validation, and testing. The Matlab software is used to build the MLP architecture. The learning algorithms used for this project is the Levenberg-Marquardt algorithms and the Quasi-Newton algorithms. Result show that trained MLP is able to give a percentage of accuracy of 99.102% in oil and gas flow pattern recognition. This shows that the MLP is suitable to be used in the oil and gas flow pattern recognition.