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- PublicationEnhancement Of ZnO-Based UV Photodetectors By Incorporating Bi₂O₃, Ag, And Ge Nanostructures Synthesized Using Laser Ablation In Liquid(2025-07)This research enhances the efficiency of UV photodetectors through the synthesis and integration of nanoparticles using laser ablation techniques. The study investigates the effects of bismuth oxide nanosheets (Bi2O3-Nsh), silver nanoparticles (AgNPs), and germanium nanowalls (GeNWs) on ZnO/Si-based UV photodetectors.
- PublicationImproving Forecasting Accuracy For Time Series Data Using Fuzzy Techniques And Wavelet Transform(2025-07)This study focuses on improving the accuracy of stock market forecasting for the Saudi Arabia stock exchange (Tadawul) by employing advanced modeling techniques and adaptive learning approaches. The study utilizes the maximum overlapping discrete wavelet transform (MODWT) in conjunction with various mathematical functions to analyze daily stock price indices data from October 2011 to December 2019.
- PublicationThe Effects Of Nannochloropsis Sp. Methanolic Extract On Prevention Of Dna Damage In L929 Cells(2023-01)Nannochloropsis and Spirulina are some of microalgae species that have been found to have a wide range of biological activities such as antioxidant and anti-DNA damage properties. Unfortunately, there is still lack of study on the effect of both microalgae especially Nannochloropsis species. Hence, this study was carried out to determine the effect of Nannochloropsis sp. extract on prevention of DNA damage in L929 cell line. The phytochemicals of both microalgae were extracted using 100% methanol. The extractions were then screened with HPLC to detect the presence of targeted compounds. HPLC analysis revealed that Nannochloropsis sp. methanolic extracts had caffeic acid, p-Coumaric acid, naringenin and hesperetin while Spirulina sp. methanolic extract had caffeic acid, quercetin and naringenin. The extracts were then tested for Total Phenolic Content (TPC) and Total Flavonoid Content (TFC). Results revealed that the extracts for both TPC and TFC for Nannochloropsis sp. were higher than Spirulina sp. with 58.43 mg GAE/g and 19.64 mg GAE/g, and 79.87 mg QE/g and 11.19 mg QE/g respectively. The study was then proceeded by evaluating the antioxidant activities of the microalgae extracts using DPPH-HPLC analysis. Nannochloropsis sp. methanolic extract exhibit greater percentage of DPPH inhibition compared to Spirulina sp. extract. A negative correlation existed between TPC and TFC with the EC50 of DPPH antioxidant inhibition activity. In this study, Spirulina sp. and Nannochloropsis sp. showed moderate toxicity toward L929 cell lines with IC50 1.701 mg/mL and 1.134 mg/mL respectively. In DNA damage analysis with Nannochloropsis sp., the result revealed that the methanolic extract are able to prevent and reduce DNA damage activity. Thus, microalgae can be proposed as one of alternative form in medical and pharmaceutical industry.
- PublicationNational Culture And Corporate Social Responsibility: A Case Of Saudi Aramco(2025-07)This research explores how national culture changes influence corporate social responsibility (CSR) practices over time in Saudi Arabia. While academic research on CSR has developed considerably, most of this research has been undertaken in developed countries, and the topic remains under researched in the Middle East, particularly in Saudi Arabia. A few studies were carried out in the country to investigate CSR, and its relationship with national culture. However, the contributing factors to CSR, and how its practices might be related to major changes in local culture are overlooked, especially in the context of Saudi Arabia, an economically powerful, originally oil-based economy, transforming rapidly into one that is more diversified, and less dependent on oil.
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- PublicationBiodegradable polyvinyl alcohol (pva) /carboxymethyl cellulose (cmc) halochromic film using natural dye from red cabbage(2024-08-01)The conventional pH indicator film is often synthetic and non-biodegradable, which can contribute to pollution and environmental degradation. In this research, a biodegradable halochromic film was fabricated using natural dye (anthocyanin) from red cabbage, PVA, and CMC and formed into film through the solution casting method. Solid-liquid extraction method was used to extract anthocyanin from red cabbage, and the optimum parameters, such as type of solvent, temperature, and time to extract a higher amount of anthocyanin, were determined. Responsiveness of halochromic film with different amounts of PVA/CMC (100/0, 80/20, 60/40, 40/60, 20/80, 0/100) was determined by using air exposure from different pH buffer solutions (pH 2–pH 12) by observing the colour change within 120 seconds and analysing the total colour difference (ΔE) by using colour analysis software. Characterization of the film was done through FTIR, swelling test, tensile test and reusability test. The finding shows the optimum parameters to extract higher amounts of anthocyanin were a 1:1 ratio of ethanol to distilled water, 70°C of heating, and an extracted duration of 30 minutes. The halochromic film with higher CMC content undergoes a faster and more obvious colour change when air exposure to different pH buffer solutions. The tensile strength and Young’s modulus increase, while elongation at break decreases as CMC content increases. Anthocyanin halochromic film shows a good sensor at pH 2, 11, and 12 as it changes to red at pH 2, green at pH 11 and greenish yellow at pH 12. Halochromic film made from 60% PVA and 40% CMC shows a balance in both colour response time and mechanical properties.
- ItemMalaysian radiographers administering intraveneous contrast media injection : radiographers' and other healthcare practitioners' perspectives(Pusat Pengajian Sains Perubatan, Universiti Sains Malaysia, 2016-02)Administration of intravenous contrast media (IVCM) injections by radiographers is one of the aspects that could be achieved to enhance patient care. However, Malaysian radiographers cannot perform IVCM injections. The examination requiring IVCM injections are delayed until authorized healthcare practitioners fulfil the task. Consequently, this results in the increment of waiting time and may incite distraction for those practitioners who were concentrating on the other procedures at the same time. Ultimately, it will negatively impact on patient care and service delivery. Therefore, this study was aimed to develop and validate questionnaires concerning obstacles, consequences and possibilities of Malaysian radiographers performing IVCM injections. Also. It was aimed to identify the perceived hindrances and consequences may result from Malaysian radiographers performing IVCM injections, to determine the associated factors of practicing hospital, gender and designation on perceived obstacles and consequences of participants, to determine participants‟ agreement on the inclusion of IVCM administration into radiographers‟ syllabus and provision of IVCM administration and role extension for radiographers by MOH, to examine correlation between participants‟ agreement on the inclusion of IVCM administration into radiographers‟ syllabus and provision of IVCM administration and role extension for radiographers by MOH and yet to determine any significant difference exist between means score for radiographers group andother healthcare practitioners group on inclusion of IVCM administration into radiographers‟ syllabus and provision of IVCM administration and role extension for radiographers by MOH. Cross sectional and qualitative study was conducted using newly designed questionnaires involving seven hundred sixteen (716) participants for which constitute of five hundred twenty five (525) radiographers (R), eighty (80) radiologists (S), fifty eight (58) medical officers (MO) and fifty three (53) state registered nurses (SRN). They were drawn from diagnostic imaging department of thirteen (13) principal government hospitals in the Malaysia, with strategy of convenience sampling and were surveyed using questionnaires. The content validity index (CVI) for two (2) sets of developed tools for R and S, MO, SRN was 0.968 and 0.970 respectively. The reliability test (Cronbach‟s alpha) for internal consistency ranges from 0.735 to 0.824. Descriptive statistics and inferential statistics were used to analyse data. From the total number of participants, 62.3% agreed IVCM administration is not in the syllabus of radiographers training program. 84.8% of participants viewed improvement of radiographers‟ knowledge and skills whilst 69.0% conceded time reducing as the consequences. Overall, 84.4% were in favour of radiographers undertaking IVCM injections. T-test indicated significant difference between means score for radiographers group and other healthcare practitioners group on inclusion of IVCM administration into radiographers‟ syllabus and provision of IVCM administration and role extension for radiographers by Malaysian Ministry of Health (MOH), p<0.001. In conclusion, most of the participants were in favour for radiographers to undertake this role. The major obstacle was IVCM administration is not in syllabus of radiographers training program. An appropriate training concomitant with recognition through regulation for Malaysianradiographers to undertake IVCM injections role therefore is imperative to support their extended role in this field.
- ItemDevelopment Of Ultrasonic Cautery System(Universiti Sains Malaysia, 2021-07-01)The use of piezoelectric element as the primary ultrasonic transducer is prevalent in ultrasonic cautery system. Proper method to characterize an ultrasonic scalpel has become an important design process. In this study, an ultrasonic scalpel prototype was characterized using both finite element modelling and experimental procedures. FEM simulation software, Abaqus was utilized to investigate preloading effects, proper longitudinal mode shape, resonant frequency, and mechanical response due to harmonic excitation. Experimental modal and harmonic analyses were used for experimental validation. The simulated results were in accordance to the theoretical calculation for the preloading effects, where sufficient compressive stress of 27 MPa was imposed onto the piezoceramic rings and an internal stress developed within the bolt approached 190 MPa. Modal analysis detected a resonant frequency at 47740 Hz with a dominant longitudinal mode shape. For harmonic analysis, simulated result suggested 76.85 microns of mechanical displacement amplitude while experimental procedure measured 54 microns. The results concluded that the ultrasonic scalpel was successfully characterized.
- ItemRole of repeat head computed tomography in the management of mild traumatic brain injury patients with a positive initial head ct.(Pusat Pengajian Sain Perubatan, Universiti Sains Malaysia, 2010)The advent of computed tomography (CT) has revolutionized the approach to mild traumatic brain injured (MTBI) patients. CT scan has now become standard practice in the initial management of MTBI patients. Those with a positive initial head CT not requiring surgical intervention will be warded for continuous neurological observation. As a routine, a repeat head CT is frequently ordered within 24 to 48 hours, even without any clinical neurological deterioration in patients condition. The logic of this practice is questionable as convincing evidence is lacking. Indiscriminate ordering of radiological tests puts a strain on the healthcare system, especially so in Malaysia since less than 30 government hospitals nationwide are equipped with CT scans. Therefore, the objective of this study is to evaluate the role of routine repeat head CT in providing useful information that leads to a neurosurgical intervention. This is a prospective observational study of MTBI patients admitted to the Neurosurgical ward, Sultanah Aminah Hospital, Johor Bahru from 1st June 2008 to 30th September 2009. A total of 279 patients was included in the study after meeting the inclusion criteria. MTBI is defined as Glasgow Coma Scale (GCS) score of 13, 14 or 15, with at least one of the following; head trauma with loss of consciousness lasting < 30 minutes; Glasgow Coma Scale score of 13 or more; post-traumatic amnesia lasting < 24 hours; any mental alteration at time of injury; and/or any transient or persistent neurological signs. A head CT is considered positive if there was a suspicion or clear evidence of an intracranial pathology. The result of the first head CT were obtained from the radiological report from this hospital's radiologist, or when not available, from the attending neurosurgeon's interpretation as documented in the case notes. The patient's demographic data, initial neurological examination findings, and biochemical analyses were documented. Neurological status was also documented until discharge. The results of the repeat head CT scan were obtained from the radiological report from the hospital's radiologist or from the attending neurosurgeon's notes. These were categorized as improved, unchanged or worsened. Any other additional neuroradiologic imaging or neurosurgical interventions were noted until discharge. Patients were divided into two groups, one with an unchanged or improving repeat head CT (n = 217) while the other with a worsened repeat head CT (n = 62). 31 patients received urgent surgical intervention after the repeat head CT was done. In all cases, neurological deterioration preceded and prompted an urgent repeat head CT. When the 62 patients with the worsened repeat head CT were compared to the other 217 patients, they were found to have significant statistical correlation with older age ( ~ 65 years old) (p value< 0.001), lower GCS on admission (p value= 0.003), associated symptoms of headache (p value= 0.019), multiple lesion on initial head CT (p value = 0.001), haemoglobin levels on admission (p value = 0.009), longer hospital stay (p value< 0.001), higher mortality rate (p value= 0.001), higher risk to undergo surgical intervention (p value < 0.001) and higher risk for neurological deterioration (p value < 0.001 ). There was no significant difference on gender, ethnic groups, mechanism of injury, other associated symptoms on admission, types of intracranial injury on initial head CT, types of skull fracture sustained and International Normalized Ratio levels. On applying multiple logistic regression, three factors were found to independently predict a worse repeat head CT. This includes age 2: 65 years old, GCS of less than 15 (i.e. 13 or 14) and multiple lesions on initial head CT. The role of a repeat head CT in MTBI patients with a positive initial head CT have been evaluated in this study. Without a clinical neurological deterioration, a repeat head CT did not change the surgical outcome of patients. Patients with a GCS of 13 - 15 can be easily observed and assessed in the neurosurgical ward, therefore it is unnecessary to order a repeat head CT in all MTBI patients. Due vigilance is warranted in those with risk factors for a worsening repeat head CT.
- ItemFactors Influencing Continuance Usage Intention Of E-Filing System Among Taxpayers In Malaysia(Universiti Sains Malaysia, 2014-02)In this current competitive environment, it is important for businesses to accentuate on continuance usage as the key for long term growth. It has been argued that the longer a business can keep a customer, the greater the revenue can be earned from that customer and the cost of serving the customer also declines. Malaysian Government has spent huge amount of money in developing the e-Filing system which is receiving much attention and there has been an upward trend in the adoption of the system among taxpayers in the first five years. However, while initial acceptance of information system (IS) is very important toward realizing IS success but its eventual success depend on its continued use rather than first-time use. In this vein, investigating the continuance usage intention of e-filing system is deemed to be important because as more citizens use the e-filing system the more operation and management cost can be reduced. As such, the purpose of this study was to examine the continuance usage intention of the e-filing system among taxpayers in Malaysia based on three important individual beliefs which is trust in the system, personality and optimism bias. The sample size comprises 731 taxpayers from the urban states of Peninsular Malaysia which comprises Penang, Perak, Selangor, Kuala Lumpur and Johor were collected and analyzed using Structural Equation Modeling (SEM).