Repository@USM
Welcome to closed access digital repository of Universiti Sains Malaysia (USM).
This repository contains multiple types of scholarly materials, especially USM theses and exam papers.
To access the full text, please log in with your USM email account.
Research outputs
4950
Projects
0
People
0
Recent Additions
- PublicationVasorelaxant And Antihypertensive Effects Of 3,4,7,2',4'-Pentahydroxyflavone In In Vitro And In Vivo Models(2024-08)Hypertension is one of the chronic medical conditions characterised by consistently high blood pressure exerted against the wall of blood vessels. It has emerged as a major global health concern due to its increasing worldwide prevalence. Although numerous antihypertensive medications are available in the market, many are reported to have low efficacy and frequently come with adverse effects or contraindications. Consequently, the current study was designed to identify a potential antihypertensive agent which could avoid all the issues associated with currently market available medications. Morin, a flavonol which was known for its diverse pharmaceutical properties, was selected to evaluate its vasodilatory and antihypertensive activities using in vitro and in vivo approaches, respectively. The vasodilatory effect of morin and its underlying mechanism were evaluated in vitro using aortic rings assay. The results revealed that morin exerts its vasodilatory effects through multiple mechanisms pathways, including endothelium-dependent and endothelium-independent pathways.
- PublicationIntranasal Delivery Of Andrographolide Nanoparticles For Improvement Of Cognitive Function: In Vitro And In Vivo Evaluation(2024-07)This study explores the neuroprotective potential of andrographolide (ADG), a bioactive compound derived from Andrographis paniculata, and its formulations in various in vitro and in vivo models of neurodegenerative diseases. The present study focuses on the development of a reverse-phase (RP) HPLC method for the quantification of andrographolide (ADG) and neoandrographolide (NEO) in A. paniculata (AP) extract. Through meticulous experimentation, a mobile phase comprising acetonitrile and water (30:70 v/v) was identified as optimal, resulting in sharp peaks and excellent separation of ADG and NEO. The method exhibited good specificity, linearity (r² = 0.999), accuracy (% R.E ≤ 2%), and precision (% RSD ≤ 2%) over a concentration range of 1.0 – 200 μg/ml, complying with US FDA guidelines. Upon development of quantification method, ADG were formulated using single emulsion solvent evaporation method (ADGPNPs and APENPs) and spray drying techniques (NSD NPs, NSD NCs and MSD MNCs). Both the formulation strategies comprising of total 5 formulations were further characterised using SEM, TEM, FTIR, DSC, TGA and XRD. ADGPNPs, APENPs and NSD NPs which were also known to be highly amorphous, have shown a spherical shape with uniform nanoparticles size distribution. Meanwhile, NSD NCs and MSD MNCs which revealed a crystalline nature has a non-uniform size and shape of squares, semi-squares, and rectangle crystals.
- PublicationEvaluation Of Pre-Storage Leucoreduction Effect On Pro And Anti-Tumour Cytokines In Whole Blood During Storage(2024-08)The presence of white blood cells (WBCs) and cytokines in whole blood (WB) during storage may have effect on cancer patients requiring blood transfusions. This study aims to determine the residual of WBCs in WB following leucoreduction and changes in cytokine levels which occur during storage of WB. A total of 31 donors were recruited in this study. Three hundred fifty millilitre of whole blood (WB) was withdrawn from each donor. Half of the blood volume (175 mL) were leucoreduced (LR), while the other half (175 mL) were not leucoreduced and used as a control. Full blood count (FBC) was done using Sysmex KX-21, Japan and residual WBCs subsets were measured using FACSCanto™ II Beckton Dickinson, USA. Cytokines levels from plasma non LR and LR bags on day 0, 10, 20, and 30 days was measured by ELISA method. T-helper (Th) lymphocyte subgroups and gene expression were analysed in the non-LR samples by real-time polymerase chain reaction, respectively. There was a significant difference in the mean of all FBC parameters and residual WBCs subsets between these two groups (p < 0.05). Levels of IL-2 and IL-6 were not detected in both bags during storage. There was a significant difference in TGF-β and IFN-γ between non-LR and LR on day 0 to day 10. TGF-β level showed an increase up to day 30. T-bet, GATA-3, and Foxp3 gene expression were detected in non-LR samples. Leucoreduction demonstrated a significant effect on blood parameters, cytokine levels, and gene expression, emphasizing its importance in WB storage.
- PublicationMental Health Literacy Among Tertiary Education Students: Perspectives From University Students And Educators(2024-07)University students’ perspectives on mental health issues remain scarce despite the growing prevalence of mental illness among this population. Using a qualitative approach, this thesis explored students' perceptions and beliefs about mental health and mental illness, mental health help-seeking, as well as educators' perspectives on students' mental health literacy and their roles and challenges in supporting students' mental health. Virtual or face-to-face interviews using a semi-structured interview guide were conducted independently among university students and educators between December 2021 to July 2022. All interviews were audio-recorded, transcribed verbatim and analysed using thematic analysis. Sixteen university students and twelve educators were interviewed. Most student informants related mental health to an individual's thoughts, emotions and behaviours, while a minority equated 'mental health' with 'mental illness'. Students perceived socio-environmental factors as the primary cause of mental illness. Nearly all informants expressed positive attitudes and willingness to help people with mental illness.
- PublicationDiffusion tensor imaging and fibre tractography of leukoaraiosis.(2016)Diffusion tensor imaging (DTI) is an important technique in magnetic resonance imaging (MRI) which is utilized in brain imaging . DTI detects and measures mobility of water molecules in biological cells. It also provides scalar indices which is mean diffusivity (MD) and fractional anisotropy (FA). Futhermore, the neuron fibre bundles can be visualized by using special technique in DTI, namely fibre tractography. Leukoaraiosis is a type of abnormal appearance in the white area of human brain and this region appears hyperintense on T2- weighted and fluid attenuation inversion recovery (FLAIR) magnetic resonance (MR) images. It is commonly found in normal elderly which is related to ischemic stroke and cerebrovascular disease. The objective of this study is to reconstruct the DTI parametric maps and fibre tractography and measure the DTI values and number of fibres in corpus callosum(CC) and corticospinal tract(CST). It is also to compare the FA and MD values obtained between right and left of CST. The subject had leukoaraiosis at right side frontal white matter region and data analysis was acquired by using commercial software, NordicICE Version 2.3.13. MD. FA, and colour coded FA maps and fibre tractography were constructed. Region of interest were located at corpus callosum and at right and left side of corticospinal tract. For CST no differences was found for MD and FA values at both sides. Fibre tractography showed right CST have 17.4% lesser number of fibers compared to left CST. Whereas, for corpus callosum the MD value is 96.52 ± 30.34 and FA is 0.56 ± 0.19 with 11451 number of fibres. In conclusion, DTI parametric maps and fibre tractography has been reconstructed, DTI values and number of fibres in CC and CST also can be measured. The comparison of DTI values between right and left side of CST was successfully obtained.
Most viewed
- ItemDevelopment Of Various Modified Maize Cob As Adsorbents For Methylene Blue Dye Wastewater Treatment(Universiti Sains Malaysia, 2013-07)The adsorption of basic dye, Methylene Blue (MB) onto raw maize cob (RMC), acid modified maize cob (AMMC), ferric oxide (Fe3O4), raw maize cob impregnated with ferric oxide (RMC-Fe3O4) and acid modified maize cob impregnated with ferric oxide (AMMC-Fe3O4) have been investigated in this study. The effects of pH, adsorbent dosage, initial dye concentration, contact time and temperature on dye concentration removal and COD reduction were investigated by screening process and optimized by response surface methodology (RSM). All the effects showed statistical significance and the adsorption process using AMMC-Fe3O4 showed the highest effectiveness among the five adsorbents. The adsorption process using AMMC-Fe3O4 obtained the highest percentage of dye concentration removal (99.63%) and COD reduction (99.48%) at the optimum conditions with 0.75 g/100 mL of adsorbent dosage, pH 10.31, 156 mg/L of initial dye concentration for 36 minutes under 38.40 oC. The kinetic experimental data were analyzed using four kinetic equations which include pseudo-first-order model, pseudo-second-order model, external diffusion model and intraparticle diffusion model to determine the mechanism of adsorption and potential rate-controlling step. All five adsorbents showed the best fit with pseudo-second-order kinetic model. The experimental equilibrium data were tested on three isotherm models which included Langmuir isotherm, Fruendlich isotherm, and Temkin isotherm.
- ItemThe 2nd International conference on prevention & management of chronic conditions(Pusat Pengajian Sains Perubatan, Universiti Sains Malaysia, 2011)This study explored the educational needs of home-based stroke patients and family caregivers in the Kelantan state located at the northern part of the Malaysia Peninsular. This study used a qualitative approach guided by a theoretical framework, "Stroke Care Community Model" developed for this research. This study was in two phases. Phase 1 involved semistructured interviews with stroke patients, family caregivers and key members from health professionals. Phase 1 established the educational activities currently received and needed by patients and families. Phase 2 involved presenting the findings from Phase 1 to the previously interviewed health professionals through focus groups and individual interviews with the aim of establishing priorities and processes to develop education strategies for home-based stroke patients and their families. The fmdings revealed that the provision of information and education does not meet the needs of many patients and families. The educational needs are on a wide range of topics on stroke and stroke care. The findings also revealed some needs are religiously and culturally bound around prayer and traditional healthcare practice such as traditional massage. Therefore, there is a need to take the knowledge of what makes a difference to health outcomes of patients and families in a western context and work with this, utilising what is important in the culture of people at a local level. The next step to progress addressing educational needs requires a structured approach involving the formation of a multidisciplinary stroke team that incorporates cultural and religious practice.
- ItemPeperiksaan Perkhidmatan Penolong Pegawai Keselamatan KP29 Kertas II 19 Julai 2017 (Teori)(Universiti Sains Malaysia, 2017-07-19)Tarikh : 19 Julai 2017 (Rabu) Masa : 9.00 pagi – 11.30 pagi (2 ½ jam) Tempat : Kampus Induk
- ItemThermoforming process simulation of Stretchable electronic circuit(2018-05)Thermoforming is a well-known manufacturing process where a polymer sheet is heated to pliable condition at the forming temperature and stretched into a specific shape in a mould and finally trimmed to obtain a usable product. Thermoforming process is used widely in industry because of its cost-effective manufacturing process. The main objective of this project is to study the effect of the thermoforming process and parameter on the thickness distributions of the thermoforming product by using ANSYS Polyflow simulation. ANSYS Polyflow simulation is used to study the overall thermoforming process to save time and reduce the cost used to produce any prototype product. Mould with different shapes which are corner edge (3mm fillet) and sharp edge are used and simulated to obtain the best thickness distribution on the product. Mould with corner edge (3mm fillet) reduced and distributed the stress more evenly on the product. Therefore, the value of the thickness at the inside corner (critical corner) has been reduced. Grid analysis is performed on the thermoforming product with and without printed circuit. The result showed that the substrate elongated more without the printed circuit on it. The deformation of the substrate with printed circuit embedded on it is much lower. However, the substrate is able to well deform with the printed circuit according to the shape of the mould. Larger area stretch ratio is found at the critical corner and lower sidewall. Higher elongation occurred as the depth of draw increased. Therefore, the thickness distributions are reduced and increased the area stretch ratio as the depth of draw increased. In conclusion, the understanding and technique of thermoforming process on the lighting part has been fully developed.
- PublicationKombinasi rangkaian neural buatan dengan model linear: aplikasinya dalam Sains Kesihatan(2024-05)Pembangunan metodologi yang mengintegrasikan model linear dan rangkaian neural buatan dalam bidang sains kesihatan adalah suatu pendekatan yang menarik untuk meningkatkan kualiti pemodelan berserta ramalan. Kajian sebelum ini cenderung memberi penekanan kepada teknik tunggal, yang terbukti tidak mencukupi secara komprehensif. Justeru, terdapat keperluan secara statistik yang lebih holistik yang menggabungkan beberapa teknik, seperti model LiReNN, untuk meningkatkan ketepatan dalam pemodelan sains kesihatan. Kajian ini bertujuan untuk membangunkan model regresi linear dengan rangkaian neural yang menumpukan kepada kecekapan, tahap kompetensi, membuat peramalan, dan mengesahkan ketepatan model, serta mempermudah proses analisis data melalui antara muka pengguna grafik (GUI). Pendekatan gabungan ini melibatkan penggunaan butstrap, regresi linear, dan rangkaian neural hadapan suapan berbilang lapisan, disokong oleh GUI. Ketepatan kaedah dinilai melalui nilai MSE.net dan R2, menunjukkan peningkatan yang signifikan dalam ketepatan, keberkesanan, dan kecekapan analisis data. Hasil ini membantu dalam pembangunan metodologi penyelidikan yang lebih kukuh, menyokong keputusan yang lebih tepat, dan menyediakan penggunaan GUI yang lebih interaktif. Pendekatan ini meningkatkan keberkesanan aplikasi pemodelan LiReNN, membolehkan pengguna untuk mencapai hasil optimum tanpa keperluan kepada pengetahuan mendalam dalam pengaturcaraan atau analisis data. Secara keseluruhan, pendekatan ini tidak hanya meningkatkan ketepatan dan kecekapan analisis data, tetapi juga menyediakan antara muka pengguna yang lebih mesra pengguna dan efisien melalui penggunaan GUI.