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- PublicationA Study Of Selected Housing Issues In The Housing Industry(2004-04)This research has attempted to study and discuss how do these housing issues relate to the existing policies, regulations and also the future concepts, which introduce by the govemment. This is because the most hot-debated housing issues for nowadays are mostly related to provision of housing and the local authorities Although there are rules and laws to be followed throughout the whole process before the starting of one housing project until the completion and handing over to buyers, we must bear in mind that those good laws only work under enforcement. Same with all types of housing policies, which the government has put in effort to solve the existing and also the foreseeing housing issues
- PublicationThe analysis multifrequency tympanometry among Malay children aged 1-4 years old(2025-08)Tympanometry using 226 Hz probe tone is commonly employed as an excellent noninvasive test with high sensitivity and specificity used to assess middle ear function. To increase sensitivity in detecting middle ear pathology, multifrequency tympanometry is recommended. This study investigated multifrequency tympanometry (226 Hz, 678 Hz, and 1000 Hz) in Malay children aged 1–4 years to evaluate middle ear function and to provide preliminary reference values for this population. Using a cross-sectional design, 38 children (76 ears) were recruited from daycare centers and audiology clinics in Kelantan, Malaysia. All participants underwent hearing screening including otoscopy, DPOAE, and screening acoustic reflex testing followed by multifrequency tympanometry. The results of tympanometric parameters showed excellent test–retest reliability across all probe frequencies (226 Hz, 678 Hz and 1000 Hz), as indicated by intraclass correlation coefficients (ICCs). The tympanometry parameters included ear canal volume (ECV), static admittance (SA), tympanometric peak pressure (TPP) and Tympanometric width (TW). Using 226 Hz, ICCs ranged from 0.765 to 0.976, using 678 Hz ICCs ranged from 0.903 to 0.998 and 1000 ranged from 0.821 to 0.979. The Kruskal–Wallis tests showed that ear canal volume (ECV) and static admittance (SA) changed significantly across probe frequencies. Specifically, ECV was higher at 678 Hz compared to 226 Hz, and SA values were significantly different between all frequency pairs. In contrast, tympanometric peak pressure (TPP) did not show any significant differences across frequencies. Correlation using Spearman’s correlation analyses showed that in Malay toddlers aged 1–4 years, ECV and SA slightly increased with age, with the strongest correlation for SA at 678 Hz. In contrast, age had little effect on TPP and TW, as these showed weak and non-significant negative correlations. Indicating the increase in ECV and SA with Age suggests that as Malay toddlers grow, their ear canal size and middle ear compliance also increase. This reflects normal anatomical and physiological development of the middle ear system during early childhood. These findings support the clinical value of tympanometry parameters in identifying middle ear characteristics in young children and provide preliminary reference data specific to the Malay paediatric population. However, larger studies involving diverse ethnic groups are needed to establish comprehensive normative standards
- PublicationEvaluation of the effectiveness of the removable mandibular retractor with slow maxillary expansion compared to the bone-anchored intermaxillary traction with rapid maxillary expansion in the correction of skeletal class iii malocclusion associated with maxillary constriction in growing patients: a randomized controlled trial(2025-08)This randomized controlled trial aimed to evaluate the effectiveness and acceptability of the bone-anchored intermaxillary traction (BAIMT) with rapid maxillary expansion (RME) in comparison with removable mandibular retractor (RMR) with slow maxillary expansion (SME) in the correction of skeletal class III malocclusion associated with a maxillary constriction in terms of treatment time. Moreover, sagittal and transverse skeletal changes, dento-alveolar and soft tissue changes, and Patient-Reported Outcome Measures (PROMs) were also assessed. The final sample consisted of 26 patients (13 males, 13 females), ages ranging 12-15 years who were assigned to two groups randomly: BAIMT with RME group (14 patients, mean age 14.09±1.12 years) and RMR with SME group (12 patients, mean age 13.04±1.46 years). After correction of malocclusion in the sagittal and transverse planes, patients underwent a 3-month retention phase. Lateral and anteroposterior cephalograms and dental casts were taken of all patients participating at two assessment times: before the beginning of the treatment, and at the end of the retention phase. Furthermore, the levels of pain, discomfort, functional impairment, and shyness were evaluated using a standardized questionnaire that was distributed to the patients at five assessment times: (T1) after one day of the beginning of the active treatment, (T2) after one week (T3) after four weeks, (T4) after 3 months, and (T5) after 6 months. Intraclass correlation coefficients (ICCs) were applied to determine the reproducibility of the employed method, i.e. intra-observer reliability (or random error), whereas paired t-tests were applied to determine any systematic error. The data distribution for all study variables was initially tested using the Shapiro-Wilk normality test. Thereafter, Two-sample t-test, or its nonparametric counterpart, the Mann-Whitney U test, was used to detect the significance of the differences between the two groups regarding treatment duration, cephalogram data, and dental cast. For PROM questionnaire data, the Chi-square test was used. For all variables, Intraclass correlation coefficients values were in the range of excellent correlation. The results showed that the duration of both expansion and active treatment phase was significantly lower in BAIMT group compared to the RMR group (p<0.001). Sagittal skeletal and soft tissue analysis showed a significant difference between the two groups only regarding Co-Gn (p=0.039) and ANS-Me (p=0.008) in favor of RMR with SME. However, no significant differences were found between the two groups regarding the variables studied on both the anteroposterior cephalograms and dental casts (p>0.05). Regarding Patient-Reported Outcome Measures assessment, the speech difficulties level was significantly greater in the RMR group compared to the other one only at T1 (p=0.006). In contrast, mandibular movement restriction was significantly greater in the BAIMT with RME group compared to the other one only at T2 (p=0.042). Both BAIMT with RME and RMR with SME are capable of correcting Class III malocclusion associated with a maxillary constriction in growing patients with permanent dentition by making similar skeletal, dental, and soft tissue changes
- PublicationPembangunan Tanah Rezab Melayu: Kajian Kes Negeri Kelantan(1998-02)kajian ini bertujuan untuk melihat pembangunan Tanah Rezab Melayu di Negeri "Kelantan serta meneliti sejauh mana kesan positifnya terhadap pembangunan ekonomi Orang Melayu. Orang Melayu yang dimaksudkan di sini merupakan Orang Melayu Anak Kelantan atau Orang Melayu yang menetap di Negeri Kelantan. Analisis kesan meliputi peningkatan nilai hartanah, pendapatan isirumah, bilangan pekerjaan, pemilikan ruang perniagaan dan perolehan unit pembangunan oleh Orang Melayu. Analisis kajian melibatkan pengumpulan data primer iaitu dari bancian dan pemerhatian tapak dan temuramah serta data sekunder dari bahan-bahan bercetak atau penerbitan-penerbitan dan dokumen-dokumen.
- PublicationInvestigation On Antiproliferative Mechanisms Of Alstonia Angustiloba- Silver Nanoparticles In Skin Squamous Cell Carcinoma(2023-08-15)Traditional methods of nanoparticles synthesis frequently use toxics chemicals and substantial energy, which may have detrimental effects on the environment and human health. Recently, plant-based synthesis of nanoparticles (AgNPs) has emerged as a promising green synthesis method. Herein, we reported the green synthesis of AgNPs using the aqueous extract of A. angustiloba leaves and assessed its antiproliferative mechanisms. Initially, the physiochemical properties of A. angustiloba-AgNPs were characterised using UV–Vis spectrophotometry, FT-IR, FESEM, EDX, TEM, XRD and zeta sizer analyses. The cytotoxicity of A. angustiloba-AgNPs was examined by MTT assays against the A431 cancer cell line. The morphology of the treated cells was examined using fluorescence microscopy and the antiproliferative mechanisms of the nanoparticles in A431 cells were investigated by annexin-FITC/propidium iodide (PI) staining and DNA cell cycle analysis using flow cytometry. The intracellular ROS levels were measured using a commercially available kit. The expression of apoptosis and cell cycle-related proteins was determined by Western blotting. The results of SEM and TEM revealed that the nanoparticles showed a spherical shape with the highest particle size distribution was 11 to 14 nm, while a mean hydrodynamic size of 61.21 ±3.96 nm and a zeta potential value of –18.67 ±3.12 mV that was measured by DLS. Besides that, the XRD pattern showed that metallic Ag has a face-centred cubic structure with the diffraction peak values at 2θ of 38.11°, 44.26°, 64.29°, and 77.07° corresponding to lattice planes at (111), (200), (220), and (311), respectively. FTIR results revealed the presence of –OH, C=C and C-O may serve as a capping and stabilising agent. The nanoparticles inhibited the growth of A431 cells with an IC50 value of 39.58 μg/mL after 72 h of treatment. Meanwhile, the IC50 values for extract alone and commercial AgNPs were 164.3 ug/ml and 16.89 ug/ml, respectively. Further investigation has shown that the nanoparticles induced both apoptosis and cell cycle arrest at S-phase in A431 cancer cells. Western blotting analysis revealed that A. angustiloba-AgNPs decreased the expression of Bcl-2 while increasing the expression of cleaved caspase-3, 9 and Bax. Moreover, the downregulation of cyclin E protein indicated impaired progression in the S phase of the cell cycle. In summary, A. angustiloba-AgNPs inhibit cell proliferation and promote apoptosis in A431 cancer cells through increasing intracellular ROS production and activating the caspase-dependent apoptotic pathway and cell cycle arresting. These preliminary findings provided an insight that A. angustiloba-AgNPs have high anti-neoplastic potential, therefore further pharmacological studies should be conducted to unveil its attractiveness as an anticancer agent.
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- ItemControl, Regulations And Legitimacy Of An Islamic Bank: An Indonesian Case Study(Universiti Sains Malaysia, 2014-01)This is a research about an Islamic bank in Indonesia that has managed to maintain its existence and grown over the two decades of its operation in Indonesia. The purpose of this research is to understand how the bank gains and maintains its legitimacy from its diverse stakeholders, specifically in terms of the way the bank is regulated/controlled and how the external control mechanism influences the bank’s internal practices of the bank. This research also reviews the history of banking, in general, as well as of Islamic banking in Indonesia to obtain a contextual understanding of the issues This research uses a case study approach informed by the new institutional sociology (NIS) and legitimacy theory. The NIS theory is used to analyse how the Islamic bank responds to pressure and influence from the stakeholders. The legitimacy theory is used to analyse how the Islamic bank gains and maintains its legitimacy from the stakeholders. Data were generated from 24 interviews with the management of the bank and as the regulators as well as from documentary evidence and observations. This research found that the bank faced various pressures and influences with the most critical pressure coming from the regulator through control and regulations. However, the pressures are sometimes conflicting; with investors demanding high profit while the public expect the bank to play a social role. The bank finds innovative ways to respond to such conflicting pressures, and, as a result, gains legitimacy from its stakeholders.
- PublicationSimulation study of biodiesel production via transesterification process from waste cooking oil(2021-06-01)Biodiesel is an environmental-friendly and alternative liquid fuel that can be used to substitute conventional diesel. It can be produced by a variety of feed stocks such as animal fats, non-edible oils and by-product of the refining vegetable oils. Biodiesel becomes a spotlight as a renewable fuel that is non-toxic and is biodegradable. It is usually synthesised by the transesterification of vegetable oil or animal fat with short chain alcohol such as methanol or ethanol. Its high oxygen content makes it a better choice for diesel engines. Waste cooking oil is one of the feedstocks that can be converted into biodiesel. Therefore, in this simulation study, waste cooking oil has been used as the raw material that reacted with methanol. This study was done by using Matlab software to observe how the operating conditions affect on the yield, conversion and selectivity of biodiesel. It was found that the temperature of 60 ̊C exhibited the highest yield of methyl ester. Oil to alcohol ratio of 1:15 gives the highest yield at 59%and catalyst weight of 1.4 wt % leads to the maximum yield of biodiesel. The simulation results obtained reasonable with the literature results and within the range studied by the previous researchers.
- ItemPengetahuan Dan Tingkah Laku Pengguna Dadah Secara Suntikan (IDU) Yang Mengikut Program Pertukaran Jarum Dan Alat Suntikan (NSEP) Di Pulau Pinang(Universiti Sains Malaysia, 2017-07)Kajian kualitatif ini dijalankan bagi meningkatkan tahap kualiti dan keberkesanan penyampaian perkhidmatan dalam Program Pertukaran Jarum dan Alat Suntikan (NSEP) kepada pengguna dadah secara suntikan (IDU). Objektif kajian ini meliputi: (1) mengenal pasti ciri-ciri sosiodemografi IDU yang terlibat dalam NSEP; (2) meneroka pengetahuan IDU yang terlibat dalam NSEP berkaitan HIV/AIDS, HCV, VCT dan NSEP; (3) meneroka bentuk tingkah laku IDU yang terlibat dalam NSEP berkaitan dengan tingkah laku suntikan dan tingkah laku hubungan seks; (4) menganalisis halangan dan cabaran IDU dalam mengamalkan tingkah laku pengurangan risiko; dan (5) mencadangkan strategi atau peranan yang boleh dipraktikkan oleh pekerja sosial dalam meningkatkan lagi keberkesanan NSEP ke arah pembentukan tingkah laku pengurangan risiko dalam kalangan IDU. Kajian ini telah dijalankankan di Pulau Pinang dengan melibatkan seramai 20 orang responden. Kaedah temu bual mendalam berlandaskan panduan temu bual separa berstruktur telah digunakan dalam proses pengumpulan data. Penemuan kajian mendapati dalam konteks pengetahuan bahawa: (1) IDU mempunyai pengetahuan mengenai HIV/AIDS yang baik; (2) IDU tidak mempunyai pengetahuan mengenai HCV yang baik; (3) IDU mempunyai pengetahuan mengenai VCT yang baik; dan (4) IDU mempunyai pengetahuan yang baik mengenai NSEP. Dalam konteks tingkah laku menyuntik dadah dan hubungan seks pula, didapati bahawa: (1) tingkah laku penggunaan jarum dan picagari adalah secara amalan pengurangan risiko; (2) tingkah laku menggunakan pad alkohol adalah secara amalan pengurangan risiko; (3) penggunaan kapas adalah secara amalan pengurangan risiko; (4) tidak menggunakan tourniquet secara amalan pengurangan risiko; (5) mengamalkan pemilihan urat berbanding arteri; (6) mengamalkan penukaran kawasan anggota badan bagi tujuan menyuntik dadah; (7) tidak mengamalkan penyimpanan jarum dan alat suntikan yang telah digunakan di tempat yang selamat; dan (8) IDU tidak aktif dalam tingkah laku hubungan seks.
- PublicationFabrication and characterization of electrospinning biodegradable fabric layer for face mask application(2022-08-19)The increased use of 3-ply facemasks has raised concerns about the pollution they cause to the environment. The non-biodegradability of current 3-ply facemasks is highlighted because it is difficult to manage the waste and much more pollution is created when facemasks are discarded. Several studies have been conducted in order to improve the filtration layer on a consistent basis by using biodegradable polymers as an alternative. The present study aimed to fabricate polylactic acid (PLA), poly (butylene adipate-co terephthalate) (PBAT) and PLA/PBAT fibre mat layers. The effect of different needle sizes on the properties and morphology of PLA and PBAT fibre mats was identified by using the Scanning Electron Microscope (SEM) tabletop, ImageJ and Universal Tensile Machine (UTS). In addition, the effect of single and binary solvents was investigated to produce PLA/PBAT fibre mat layer. Results showed that small size needles produced small-diameter fibres. The best needles to use for the fabrication of the PLA and PBAT fibre mats are 25G and 23G, respectively based on the fibre diameter and tensile properties. A 25G needle produced the smallest diameter and compact fibre mat. However, a 21G needle produced a PLA fibre mat with the highest tensile strength and Young’s modulus. On the other hand, a 25G needle is the best needle size to produce a PBAT fibre mat with good tensile properties. Binary solvents using DCM and DMF produced continuous and thinner fibres and showed higher tensile properties compared to the single solvent system.
- ItemCrash recovery support for variable strength t-way test generation strategy(2016-06-01)Often, the biggest challenge in software testing relates to the fact that it is not feasible to test for all the input parameters exhaustively owing to constraints in costs, resources and time. Considering these factors, software testers must appropriately sample the test cases in order to best utilize the resources at hand. Within the context of Combinatorial Testing, testers often resort to t-way test generation strategy (where t indicates the strength of interaction). Empirical evidence in the literature indicated that t-way test generation strategy has managed to minimize the test cases significantly whilst maintaining the fault detection capability of the testing process. Much useful progress has been achieved as far as the development of t-way test generation strategy is concerned. Nevertheless, some issues remain especially in the context of addressing ever increasing complexity and size of software (i.e. lines of code) resulting into high number of interaction among input parameters. Firstly, the test generation can be painstakingly long, interruption is expensive as the whole generation process needs to be restarted from scratch. Time and efforts will also be wasted. Secondly, existing strategies commit too early on selection of the best value of input parameters when sampling of the test cases. For this reason, these strategies were less sufficient in terms of generating optimal test suite size. Here, to enhance the t-way testing capability, there is also a need to consider variable-strength strategy. This approach is often favored because of the compromise in terms of test suite size as the strategy focuses testing where it has the most potential value which usually is associated with a risk analysis and priority. In order to address these issues, this research develops a variable-strength (VS) interaction t-way test generation strategy, called Test Suite Generator with Crash Recovery support (TSGCR). Unlike existing strategies, TSGCR adopts Multilevel Greedy algorithm, which delays choosing the best value until it satisfies certain rules. To provide a reliable operation, TSGCR also permits crash recovery support integrated as part of the strategy itself. As the test generation can potentially be long lasting processes (i.e. due to large selection of input parameters and values), TSGCR tolerates involuntary transaction failures (e.g. such as power failure or system errors) or voluntary execution suspension (e.g. to give ways for other computations) enabling restoration of state and data to the last consistent state. To evaluate the competitiveness of TSGCR, the test generator is tested with uniform and mixed input parameters and the performance (in terms of the generated test suite size) is compared with existing variable strength t-way test generation strategies using well-known standard benchmark configurations (based on six sets of experiments). Benchmarking results showed that for VS interaction configurations for uniform input parameters, TSGCR is able to get seven Δ with 0 value, i.e. similar value to the best solution obtained by other strategies, seven Δ with +ve values, i.e. able to get the best solution; from fourteen out of forty four experimental results. While for VS interaction configurations for mixed input parameters, TSGCR is able to get twenty seven Δ with 0 value, eight Δ with +ve values; from thirty five out of forty one experimental results. Hence, the results demonstrated that TSGCR produces competitive results as far as the size of the test suite is concerned against most existing strategies.