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- PublicationIn vitro antioxidative evaluation of plukenetia volubilis aqueous extract in ovarian aging process(2025-01)Ovarian aging is the aging process related to the decline in ovarian cellular function primarily driven by oxidative stress which affects hormonal production, resulting in reduced fertility and hormonal dysfunction in women. Although there are many medications have been developed to increase fertility and reproductive hormones such as clomiphene citrate and gonadotropins, they can cause short- and long-term effects on women. Plukenetia volubilis (Sacha Inchi) is a plant that originated from Northwestern Brazil and Peru and has proven to contain high antioxidant contents such as tocopherols and phenolic compounds. Therefore, our study aims to evaluate the antioxidative potential of P. volubilis aqueous extract in combating oxidative stress during the ovarian aging process using in vitro models. This study assesses the total phenolic content of P. volubilis aqueous extract via total phenolic content (TPC) assay, its radical scavenging ability via DPPH assay, and its protective effects on granulosa cells (COV434) subjected to oxidative stress via MTT assay. Ascorbic acid is used as a standard antioxidant to compare the results. As a result, the TPC assay confirms the presence of significant phenolic content in the extract where the phenolic contents increase as the concentration increases from 0.2 mg/ml to 15 mg/ml. Next, The DPPH assay shows the increase of DPPH radical scavenging with the IC50 value of 2.27 mg/ml. P. volubilis aqueous extract also shows a significant radical scavenging activity when compared to ascorbic acid (p = 0.009). Additionally, the MTT assay reveals the significant protective effects of the extract against hydrogen peroxide-induced oxidative stress in COV434 cells when compared to ascorbic acid (p = 0.089) with the EC50 value of 23.82 mg/ml. This is proven by increasing cell viability when treated with P. volubilis aqueous extract. Overall, the findings successfully underscore the promise of P. volubilis as a natural antioxidant to mitigate oxidative stress-related ovarian aging
- PublicationAssesment of monocyte phagocytosis in the presence of synovial-fluid-derived exosomes from osteoarthritis patients(2025-01)Osteoarthritis (OA) is a degenerative joint disease characterised by cartilage degradation, inflammation, and joint dysfunction, and monocytes play an important role in its pathogenesis via phagocytosis and inflammatory regulation. This study investigated the effect of synovial fluid-derived exosomes from OA patients on monocyte phagocytic activity. Synovial fluid (SF) was harvested from OA patients undergoing total knee arthroplasty, and exosomes were isolated by ultracentrifugation. Monocytes from healthy donor were cultured for 24 and 48 hours at different exosome concentrations (1:10, 1:20, and 1:40). Then, pHrodo™ Green E. coli conjugates were used to measure monocyte phagocytosis, which was quantified by flow cytometry. The findings demonstrated a significant increase in monocyte phagocytic activity upon exosome treatment, indicating a modulatory effect. These findings provide insight into the interaction between exosomes and monocyte in OA pathogenesis, underlining the possibility of exosome-based treatments to manage this degenerative illness
- PublicationThe detection of multidrug-resistant klebsiella pneumoniae using polymerase chain reaction(2025-01)Multidrug-resistant Klebsiella pneumoniae (MDR-Kp) is a major worldwide medical concern, particularly in healthcare settings because it is resistant to multiple antibiotics. This resistance is caused by enzymes such as beta-lactamases and carbapenems, which limit treatment options and increase mortality rates. Polymerase chain reaction (PCR) was used in this study as a fast and accurate way to detect genetic markers for bacterial identification and resistance genes. The study aimed to use PCR for detection of 16S ribosomal RNA (16sRNA), beta-lactamase TEM (blaTEM), cefotaximase-M-1(CTXM-1) and New Delhi metallo-beta-lactamase 1(NDM-1) in K. pneumoniae. Archived samples were collected from the INFORMM Biobank, cultured under aseptic conditions and their DNA was extracted using the boiling method. PCR was performed with specific primers and 2% agarose gel electrophoresis was used to visualize the amplified products. The results showed successful amplification of 16sRNA gene (100%) in all isolates confirming the bacterial identity. The blaTEM and CTXM-1 genes were detected in 78.9% and 89.4% of K. pnuemoniae isolates respectively, while non-specific bands were observed during NDM-1 amplification for majority (69%) of the isolates. The study demonstrates that PCR is an effective method for rapidly identifying MDP-Kp and its resistance genes
- PublicationAssessment of nursing informatics competency level among bedside nurses in Prince Mohammed bin Abdul-Aziz Hospital, Riyadh, Saudi Arabia(2025-01)Advanced clinical technology is widely used by nurses in today's healthcare settings, requiring the possession of sufficient informatics knowledge and skills. Nursing competency in this field is now essential, considering the increasing focus on patient safety and care quality through informatics. The purpose of this research is to evaluate the level of Nursing Informatics (NI) competency and determine the factors influencing this competency among bedside nurses in Prince Mohammed bin Abdul-Aziz Hospital (PMAH). The study adopts a descriptive, correlational, cross-sectional approach involving 196 nurses at PMAH. Utilizing the Nursing Informatics Competency Assessment Tool (NICAT), developed by Alphonsa Rahman in 2015, the research assesses bedside nurses' informatics competency. Additionally, the questionnaire gathers demographic data. The data was entered into SPSS 25 software, and correlation analysis was carried out. The average level of competency across all categories was significantly tilted toward 'Competent, Very Competent, and Expert' (74%), with a substantially lower percent in 'Novice or Advanced Beginner' (26%). Educational level was identified as significantly correlated with the level of nursing informatics competency (NIC) (P = 0.047). However, age, gender, years of nursing experience, and use of the health information system showed no significant correlation with NIC level. These findings underscore the significance of nursing informatics competency within healthcare organizations, as it determines nurses’ ability to effectively utilize available health information systems, thereby enhancing healthcare quality and improve patient safety.
- Publicationhe effects of scorodocarpus borneensis against drug-induced nephrotoxicity(2025-02)Diabetes mellitus is a chronic metabolic disorder characterised by insufficient insulin production or impaired insulin utilisation, leading to persistent hyperglycaemia. If left unmanaged, it can result in severe complications, including diabetic nephropathy, a progressive kidney disorder commonly associated with long-term diabetes. While metformin is a standard treatment for controlling blood glucose levels, its side effects, such as diarrhoea, vomiting, and lactic acidosis, have raised concerns, emphasizing the need for safer alternatives. Therefore, the aim of the study the effects of Kulim fruit aqueous extracts against diabetic nephropathy-induced Sprague-Dawley rats. The effect of Kulim fruit extract was studied on Vero cells and the diabetic nephropathy- induced Sprague -Dawley rats. The proliferation assay result of Kulim fruit extract obtained shown not significant percentage of cell viability when compared to metformin (p>0.05), might be due to lab technical settings. In this study, the induction of the type 2 diabetes was carried out using high-fat diet (HFD) for 4 weeks followed by injection of 55mg/kg of STZ for one week. The animals were divided into 4 groups with sample size of n=3, which were normal control, diabetic control, metformin-treated (150mg/kg) and Kulim fruit extract- treated (1000mg/kg) group. The effects of the Kulim fruit extract on serum creatine level shown significant different between treated and untreated group (p<0.05). The effects of Kulim fruit extract on blood urea nitrogen (BUN) shown significant different between treated and untreated group (p<0.05). The histopathological study shows promising effects in treating diabetic nephropathy when compared to untreated diabetic nephropathy by assessing the morphology of the glomerulus, Bowman’s space and tubules in kidney organ. The findings may provide valuable insights into Kulim fruit extract as a natural therapeutic alternative for diabetic nephropathy, offering a safer complementary approach to conventional treatments. Hence, the long term-impact of Kulim fruit extract in diabetic nephropathy model must be studied over a longer period
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- PublicationDesign of a retrofit inferarm cruthes(2008-04-01)The walking stick is a great aid when the person had an accident and his walking is impaired. It provides steadiness and stability, allowing the user to get around pretty well. By the way, for a person that unable to walk, the easiest way to help them to get around is using a wheelchair. It would help them hanging around easily with no burden to walk. But, wheelchair is not able to use in all aspect. For example, the user can't use the wheelchair to go up the staircase. Furthermore, if a person always sits on the wheelchair s without exercise, the bones of legs will get weaker. The main objective of this project is to design a crutch that can assist the disable or leg's injury person to climb up the staircase. It would help to prevent further damage or accidents when the user climbs up the staircase. Besides, the user is able to maintain proper posture, relieves damaging. stress, and reduces the overall chance of injury when climbing staircase. The project has completed with 3D solid modeling of the designed crutches with SolidWork 2007. Furthermore. COSMOS analysis was done on the critical parts of the designed crutches to make sure the factor of safety required was achieved.
- ItemMST 564 - Statistical Reliability - Oktober 2004(Universiti Sains Malaysia, 2004-10)
- ItemEffects Of Repetitive Uncontrolled Temperature Exposure On The Quality Of Packed Red Blood Cells(Universiti Sains Malaysia, 2019)Packed Red Blood Cells (PRBC) must be transfused within 30 minutes upon removal from blood refrigerator and the PRBC should not be hold in the ward where the storage temperature is not controlled. Untransfused blood which returned to the blood bank shall be discarded unless it is kept in an appropriate condition and temperature. Intermittent storage outside allowable temperature range often leads to destruction of the PRBC unit. This was a cross sectional study performed to determine the PRBC warming rates and the quality of PRBC upon repetitive exposure to uncontrolled temperature after 30 minutes and 4 hours. In this study four PRBC units (228 mL ± 37mL) collected from eligible volunteer subjects were equivalently split into two units, producing eight smaller units PRBC (±130mL) which then assigned into two groups; control and experimental group. Eight units of PRBC from both control and experimental group were tested on day 1, day 7, day 14 and day 35 of storage for haemoglobin level, haematocrit, haemolysis rate, potassium, lactate dehydrogenase (LDH), pH and sterility. The PRBC warming rate upon exposure to uncontrolled temperature were monitored and recorded. All PRBCs achieved desired quality requirement from national guideline from day 1 to day 35 for haematocrit, haemolysis rate, and sterility. However, none of the PRBC units met the standard requirement (>45g/unit) for haemoglobin starting day 14 to day 35. No significant changes observed for all PRBC’s quality over repetitive exposure to uncontrolled temperature in 35 days in experimental group (P<0.05). There was also no evidence of bacterial contamination in PRBC at the end of their shelf life.
- ItemSynthesis And Characterization Of Black Silicon By Silver-Assisted Chemical Etching For Solar Cell(Universiti Sains Malaysia, 2021-03)Crystalline silicon (c-Si) suffers from poor light absorption due to its indirect band gap and high reflection from its surface (about 35% in the visible region). This problem can be solved by texturing the surface of c-Si wafer to reduce its broadband reflection. Black silicon (b-Si) or nanotextured c-Si, has a huge potential for applications in solar cell due to its superior broadband light absorption within 300-1100 nm wavelength region. In this work, two-step metal-assisted chemical etching (MACE) is used to synthesize b-Si by combining low-annealing temperature of silver (Ag) film and short duration of etching of the c-Si wafer. For the b-Si fabrication, p-type (100) c-Si wafers are deposited with 15 nm Ag film using radio frequency (RF) sputtering process. Subsequently, the Ag film is annealed at low temperatures (200-230ᵒC) for 40 min in nitrogen (N2) ambient, producing Ag nanoparticles (NPs). Then, the c-Si wafers with the Ag NPs are etched in a solution containing hydrofluoric acid:hydrogen peroxide:deionized water (HF:H2O2:DI H2O) for a short duration (35-180 s). Effects of etching time, etchant volume ratio and annealing temperature towards surface morphological and optical properties by using atomic force microscope (AFM), field emission scanning electron microscope (FESEM) and UV-Vis-NIR (within 300-1100 nm wavelength region) of b-Si are then investigated. From the investigation, the b-Si with the lowest broadband reflection is produced by annealing at 230ᵒC for 40 min and etched for 70 s using HF:H2O2:DI H2O (1:5:10 by volume). The lowest reflection of the b-Si wafer is 3% at wavelength of 600 nm, with weighted average reflection (WAR) of 8%. The b-Si demonstrates average width and height of about 50-100 nm and 300-400 nm respectively for the nanotextures. For solar cell fabrication, the b-Si is diffused with phosphoric acid (H3PO4) and 2-butanol using temperatures between 850 to 950oC for 20 min to form front n+ emitter. The emitter is characterized using Hall effect measurement. Ag and aluminium (Al) are thermally evaporated on the front and rear surfaces respectively to form electrical contacts. From current-voltage measurement, the b-Si solar cells demonstrate short-circuit current density (Jsc) of 20 mA/cm2, open-circuit voltage (Voc) of 423 mV and fill factor (FF) of 25.4%. This corresponds to conversion efficiency (η) of 5.2%. On the other hand, the planar c-Si reference solar cells exhibit Jsc of 7 mA/cm2, Voc of 390 mV and FF of 21.7%. The low conversion efficiency of the solar cells is contributed by high shading loss due to the front metal fingers and poor quality of p-n junction formation.
- ItemMAT 122 - Persamaan Pembezaan - Mac 2005(Universiti Sains Malaysia, 2005-03)