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- PublicationInfluence Of Proactive Esg Strategies, Slack Resources, And Collective Brain On Esg Disclosure And Firm Value In Japanese Companies(2025-09)This study explores the influence of proactive ESG strategies and slack resources on ESG disclosure quality and firm value among Japanese firms, based on a crosssectional sample of 107 companies. The results show that both PESGS and slack resources enhance firm value, and that ESG disclosure quality serves as a mediator between PESGS and firm value. The study also introduces the concept of collective brain, which moderates the relationship between slack resources and firm value by facilitating innovation through shared knowledge and skills with cultural diversity among employees of firms.
- PublicationStudy of plastic solid accelerant using fourier transform infrared (FTIR) spectroscopy analysis and chemometric analysis(2026-02)Plastics are commonly present at fire scenes and may act as solid accelerants due to their combustible nature, potentially influencing fire behaviour and forensic interpretation. This study investigated the behaviour of selected plastic products under fire-related conditions using Fourier Transform Infrared Spectroscopy (FTIR) combined with chemometric analysis through Principal Component Analysis (PCA). A total of 20 plastic samples were analyzed using FTIR to obtain baseline spectra of unburnt materials. The samples were then subjected to controlled burning for a fixed duration, followed by FTIR analysis of the burnt residues. Subsequently, a small volume of petrol was applied to the burnt samples and further FTIR analysis was performed to evaluate the effects of accelerant exposure. The FTIR spectra obtained from unburnt, burnt and petrol-exposed samples were interpreted, characterized and compared to assess polymer types as well as changes in functional groups and spectral patterns. PCA was then applied to the FTIR fingerprint region to visualize clustering behaviour among the samples. The results of this study showed that plastic samples exhibited polymer-specific spectral features, allowing grouping based on polymer type. In addition, burning and petrol exposure caused observable spectral changes; however, their characteristic spectral features remained detectable, enabling identification of the polymer type.
- PublicationAuthentication of genuine and fake certificates using machine learning(2026-02)The proliferation of fake academic certificates in Malaysia has poses a crucial threat to the integrity of higher education and the credibility of the national workforce. This study was aimed to differentiate genuine and fake academic certificates by analysing their visual textural features through machine learning-based algorithms. In this study, the original physical certificates were digitalised at four scanning resolutions (100 to 400 DPI) and systematically creating 180 fake samples using nine distinct alteration methods using Adobe® Photoshop® software. Textural information was then extracted using the Gray-Level Co-occurrence Matrix (GLCM) while statistical tests were conducted to investigate the influence of the four scanning resolution and effects of different three conversion methods. The results demonstrated that scanning resolution and conversion methods possessed influence in generating the scanned certificates. Both random forest (RF) and support vector machine (SVM) models were effective for binary classification. However, in the multiclass classification of specific forgery types, the RF model outperformed the SVM. Overall, the research underscored the critical role of scanning resolution in shaping textural feature quality and validated the effectiveness of machine learning algorithms in certificate authentication. By demonstrating the feasibility of automated and scalable detection systems, this study contributed to safeguarding institutional integrity and protecting the value of educational qualifications, offering a practical pathway toward strengthening trust in Malaysia’s academic and professional landscape.
- PublicationDesign, Synthesis, In Silico And In Vitro Evaluations Of New Inhibitors Targeting Human Hypoxia Inducible Factor (Hif) Prolyl Hydroxylase Domain (Phd) Enzymes(2025-09)Hypoxia inducible factor (HIF) prolyl hydroxylase domain (PHD) enzymes play a pivotal role in oxygen sensing and regulation, making them key therapeutic targets for hypoxia-related diseases, including cardiovascular diseases (CVDs), chronic kidney disease (CKD), and anemia. However, current PHD inhibitors suffer from significant limitations, including toxicity, thromboembolic risks, and poor selectivity, necessitating the discovery of safer and more effective alternatives. This research utilises a computational-experimental methodology to discover new PHD inhibitors through the integration of molecular docking, molecular dynamics (MD) simulations, and free energy calculations, QSAR modeling, and experimental validation.
- PublicationMolecular And Cellular Analysis Of Hepg2 Hepatocellular Carcinoma Upon Deubiquitin Enzymes Otub1 And Otub2 Knockdown(2025-08)Hepatocellular carcinoma (HCC) is one of the most prevalent and deadly cancers worldwide. The deubiquitinating enzymes Otubain-1 (OTUB1) and Otubain-2 (OTUB2) have been linked to cancer progression, making them potential therapeutic targets. This study investigates the effects of OTUB1 and OTUB2 knockdown on cell viability, migration, and gene expression pathways in HepG2 cells, aiming to explore their roles in liver cancer.
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- ItemMold filling simulation for injection molding of natural rubber compound in glove fabrication(2017-07)Rubber injection molding is a process whereby a rubber mix is injected into a closed mold where the material is shaped to the desired geometry. The aim of the study was to observe and understand the behavior of the mold filling of natural rubber compound in injection molding. The numerical studies on mold filling of glove fabrication in injection molding were carried out. Injection moldings with natural rubber compounds having sections with thickness of 0.4, 0.5 and 0.6 mm have been prepared. CADMOULD software was used in the simulation with the Cross viscosity model. The effects of variation in process parameters such as temperature, location of gate, and viscosity on its mold filling were studied. A CADMOULD is employed to investigate appropriate rubber behavior during curing and viscosity model, respectively. Vulcanization at different quantities of gate have advantages in curing thin sections adjacent to thick ones because of their superior reversion resistance. Increase in temperature resulted in higher flow rate due to increase in viscosity. Cure time is highly dependent on injection temperature and the art of injection molding is to inject at the highest possible temperature consistent with freedom from scorch. The injection temperature of natural rubber depends on the injection molding machine variables such as barrel temperature. The simulation results are in good conformity and the strength of CADMOULD Rubber in handling mold filling in glove fabrication problems is proved to be excellent.
- ItemPengoptimuman, penulen dan pencirian enzim mannanase daripada aspergillus niger USM F4 melalui pemfermentasian substret pepejal (SSF) dengan menggunakan isirong kelapa sawit sebagai substrat.(2009-05)From the 9 isolates of fungi that were screened, the isolate USM F4 was found capable to produce higher mannanase activity than the other 8 of fungal isolates. The colony and microscopic morphologies identification showed that this fungal was very identical to Aspergillus niger. The production of mannanase by A. niger USM F4 was futher optimised based on the cultural conditions and fermentation medium in two main systems; flask and tray systems. The optimisation of cultural conditions and fermentation medium consisted physical and chemical parameters. The conditions in a 250 ml flask were 80% (v/w) water ~ontent, particle size of substrate ::::; 0.5 mm, inoculum size of 1 x 10 7 spore/ml, 1 Og of substrate quantity, incubated at 30±2°C, without mixing effect, with the addition of 2% (w/w) molases and 4% (w/w) ammonium nitrate and with the cultivation time of 5 days. Under the optimum conditions, the maximum production of mannanase activity was 433.84 ± 0.40 U/g substrate. There was an increment of about 54% after optimisation compared with before optimisation (281.97 U/g substrate). For tray system, two sizes were tested those were 27x 19x6 em and 4 Sx40x7 em. For the tray size of 27x19x6 em, almost the same conditions for a flask system were requested; 0.4 em substrate thickness (100 g substrate quantity), 80% (v/w) water content, particle size of substrate :S 0.5 mm, inoculum size of 1 x 107 spore/ml, incubated at 30±2°C, without mixing effect, with the addition of 2% (w/w) molases and 4% (w/w) ammonium nitrate and with the cultivation time of 5 days. For the other tray size (4Sx40x7 em), the optimised cultural conditions and fermentation medium were 0.5 em substrate thickness (400 g substrate quantity), 80% (v/w) water content, particle size of substrate:::; 0.5 mm, inoculum size of 1 x 107 spore/ml, incubated at 30±2°C, need to mix for every 24 hours, with the addition of 2% (w/w) molases and 4% (w/w) ammonium nitrate and with the cultivation time of5 days. A total mannanase production was 701.53 ± 0.82 U/g substrate (for the tray size of 27x19x6 em) and 918.68 ± 1.59 U/g substrate (for the size of 45x40x7 em). Compared to a flask system, the increment was about 62% (for the tray size of 27x19x6 em) and 112% (for the tray size of 4Sx40x7 em). A crude mannanase was purified by ultrafiltration, Superdex 75 gel filtration chromatography and QSepharose Fast Flow anion exchange chromatography. The purified mannanase was homogenous on SDS-PAGE. The purified mannanase had a specific activity of 196.42 U/mg, with 0.55% recovery and overall purification of 4-fold. The molecular mass of purified mannanase estimated by SDS-PAGE was about 47.4 kD. The optimal pH and temperature for purified and crude mannanase activity was 4.0 and 60°C, respectively. Both enzymes were stable at pH 4.0 and temperature of 60°C until 30 minutes. Chemicals and anions such asS~+, Zn2+, Fe3+, Cu2+, Ca2+, Mn2+, Al3+, Na+, K+, M!f+, EDTA, 2- mercaptoethanol and SDS at the concentration of 1.0 mM inhibited the purified mannanase activity. Overall, sodium dodecyl sulfate (SDS) became the most inhibitor component compared to other metal anions and chemicals. Mannanase activity was highly specific towards locust bean gum (LBG) at the concentration of0.5% (w/v).
- ItemThe Determinants Of Corporate Social Disclosure In The Annual Reports Of Malaysian Construction Companies: An Application Of Stakeholder Theory(Universiti Sains Malaysia, 2013-04)This study seeks to investigate the motivations that make the Malaysian construction publicly listed companies voluntarily provide social and environmental information in their annual reports. The first objective of this research is to examine the level of corporate social disclosures present in 2010 Malaysian construction listed companies’ annual reports. The second objective, is the application of Ullmann’s (1985) stakeholder framework, which contains three dimensions namely stakeholder power; strategic posture; and economic performance, to determine their ability to explain why these companies disclose voluntarily social and environmental information in their annual reports. Companies without a 2010 annual reports are omitted from the construction companies listed on the Bursa Malaysia to create a sample of 107 companies. Data was collected to measure components of corporate social disclosure, and proxies for Ullmann’s three-dimensional stakeholder framework were applied. This study examines the level of corporate social disclosures in relation to creditor stakeholder power represented by return on equity; investors’ stakeholder power represented by government shareholders and foreign shareholders and employee stakeholder power represented by employee share ownership. Evidence shows that both creditor and government shareholders (measures investor power), and employee share ownership does empower stakeholder pressure regarding the quantity and quality of corporate social disclosures. In contrast, foreign shareholders were an insignificant proxy and did not serve in explaining the level of corporate social disclosure in the companies’ annual report. The results also find that companies displaying a more active strategic posture towards social and environmental issues disclose higher quantity and quality of corporate social disclosure information than companies displaying a less active posture to these issues. Companies employ strong corporate governance mechanisms to, strategically, manage their relationship with their stakeholders through disclosing voluntary social and environmental information. The presence of corporate social responsibility committee in the companies’ board structure is also evidence of strategic posture, but only in quantity of corporate social disclosure. Companies with higher economic performance disclose a greater amount of corporate social disclosure information than, companies with lower economic performance. Economic performance represented by average return on assets. The results showed that larger companies are significantly associated with higher levels of corporate social disclosures.
- PublicationBuilding a clock for analog to digital converter timing test(2010-04-01)This thesis presents the building of a low-cost, high precision clock for the ADC timing test. There are sixteen clock stimuli required to drive the ADC chip. The 40-pin device-under-test (DUT) ADC is having a resolution as high as 12-bit. The frequency of the designed clock is 2 MHz and the voltage level is 3.3V. The proposed approach utilizes the use of simple digital logic gates to perform all the sixteen clock generation. In short, the circuit is divided into three parts; constant frequency ring oscillator, duty cycle adjustment circuit and voltage regulation circuit. Extra care is emphasized in selecting the most appropriate logic gates for circuit as different family and manufacturer of the gates leads to different results. In the proposed methodology, the model is built on a printed circuit board for a more stable performance. The test methodology was verified in simulation using MULTISIM as well as in hardware. Results show that the proposed methods in generating clocks are easy and accurate. The concept involved in the whole circuit is not complicated and easy to be comprehended. Besides, a 6-bit digital counter is constructed as the supplementary circuitry to test the digital-to-analog converter (DAC). The DAC is meant to translate back the digital output from the ADC to the analog output. Comparison between the DAC analog output and the original analog input is essential to verify the performance of the ADC. As a conclusion, the proposed clock design is the best options compared to others.
- ItemPublic Perception On Aedes Albopictus Mosquitoes, Fitness Cost To Insecticides Exposure And Its Activity Pattern In Penang Residential Areas(Universiti Sains Malaysia, 2017-05)A study was carried on Aedes albopictus mosquito in residential areas and its fitness cost in response to the insecticide exposure. The study to evaluate the current knowledge level on Aedes mosquitoes and dengue among Penang residence in urban Sg. Dua and sub-urban Batu Maung involved 202 respondents mainly on the observation of general Aedes' mosquito behaviour and its preventive measure, and lifestyle (on usage of artificial light) in changing the behaviour of Aedes mosquitoes. There is a direct link between the knowledge of the Aedes biting frequency with human lifestyle on the light use. However, the level of knowledge is poor on Aedes mosquitoes and dengue in both urban and sub-urban respondents. Following the survey, to investigate the effects of malathion and permethrin insecticides on the life history of Ae. albopictus mosquitoes were chosen for subsequent studies. The female mosquitoes were exposed to sub-lethal concentration of 1.5% malathion and 0.2% permethrin using WHO adult bioassay and female survivors were evaluated for their fitness parameters. We discovered 0.2% permethrin have significantly more effects on the fitness cost of Ae. albopictus, even though had developed resistance towards permethrin. Permethrin has decrease the fecundity, shorten the development periods on each larval stages and influence the sex ratio with more emerge male of Ae. albopictus. Regarding the increasing concern on the current activity of Ae. albopictus and Cx. quinquefasciatus mosquitoes in the residential areas, 24 hour trapping was conducted at urban Sg. Dua and sub-urban Batu Maung residence area using two different traps; BG- Sentinel Trap and CDC Fay-Prince Light Trap. CDC Fay-Prince light traps was most effective in trapping Cx. quinquefasciatus.