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- PublicationStudies on the physicochemical, biomechanical and biological properties of novel decellularized bovine scaffold for bone regeneration(2024-09)Bone grafting, the second most common transplant practice after blood transfusion, involves significant challenges in transferring xenogeneic donor bone cells to recipients due to potential immunological responses. This study aimed to explore the efficacy of producing bovine cancellous bone scaffolds by preserving the extracellular matrix (ECM) while eliminating native bone cells, comparing their physicochemical, mechanical, and biological properties with demineralized cancellous bone scaffolds. The study was conducted in three phases. In Phase I, cancellous bone blocks harvested from the bovine femoral head were physically cleansed, chemically defatted, and processed into two types of scaffolds: demineralized bovine cancellous bone (DMB) and decellularized bovine cancellous bone (DCC). Both scaffolds were freeze-dried and gamma-radiated. Various analyses, including histology, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy, were performed to evaluate the scaffolds. Recellularization studies was done using human osteoblast cells showed that DCC scaffolds produced a complete acellular ECM with wider pores, retained collagen fibrils, and exhibited better cell attachment, proliferation, and mineralization compared to DMB. In Phase II, the immuno-compatibility of DMB and DCC scaffolds was tested in male Balb/c mice models following peritoneal implantation. The results revealed that DCC scaffolds elicited significantly lower white blood cell counts and systemic inflammation compared to DMB and untreated native bone. Immunotoxicity analyses showed that the DMB group had higher CD4+ counts and increased pro-inflammatory cytokine expression, while the DCC group exhibited a more favourable immune response, with more CD8+ T cells and normal organ morphology, indicating better immuno-compatibility. Phase III focused on the bone regeneration capabilities of DMB and DCC scaffolds in male Sprague-Dawley rat calvarial critical-size defects. The study found that DCC scaffolds significantly promoted new bone formation, with enhanced defect closure and higher bone density observed in micro-CT analyses compared to DMB. DCC sites also demonstrated elevated mRNA levels of osteogenic markers such as osteonectin, osteopontin, and osteocalcin. RAMAN spectroscopy showed an increased abundance of collagen and bone minerals, particularly phosphate ions (PO43-), in DCC scaffolds. In conclusion, the decellularization technique effectively produced an acellular DCC scaffold with minimal ECM damage and superior osteogenic potential in both in vitro and in vivo models. DCC scaffolds demonstrated better immuno-compatibility and greater bone regeneration potential than DMB, making them a promising option for bone grafting applications.
- PublicationDevelopment Of A Formative Assessment Regime For Chinese-english Interpreter Training And Its Effects On Academic Achievement, Motivation, And Collaboration(2024-11)In China’s interpreter training programs, efforts to systematically develop and enact a formative assessment regime has been rarely documented in the extant body of scholarship. To gain a more comprehensive understanding of the applicability and impact of formative assessment regime, the present study adopted a multi-phase approach to explore the development, implementation, and learned lessons of a formative assessment regime in an interpreter training program at Xinyang Agriculture and Forestry University, a focal and representative institution of higher education in China. The researcher recruited 129 second-year interpreter learners, 7 lecturers, and 10 experts as participants in the study. Methodologically, an embedded experimental design was adhered to in the study to comprehensively include the pre-intervention, intervention, and post-intervention phases within a unified research framework. For the pre-, and post-intervention phases, the research used in-depth interview and focus group discussions to obtain viewpoints and understandings of trainees and trainers, and Delphi method for evaluative judgement of the experts. For the intervention phase, mixed-method quasi experimental approach was chosen to examine the effects of the developed formative assessment regime on the academic achievement, motivation, and collaboration in interpreter training, which were measured through a summative interpreting achievement test (SIAT), an interpreter learning motivation questionnaire (ILMQ), and naturalistic observation of classroom conversations respectively.
- PublicationComputational Design And Synthesis Of Potential Ns2b-Ns3 Dengue Protease Inhibitors(2024-06)DENV2, the type of dengue virus commonly found in Southeast Asia, is a major public health concern. In week 6 of 2024, Malaysia reported with 3,631 dengue cases and 10 deaths due to DENV2, marking a 68.75 % increase from the same period in 2023, as reported by the World Health Organization (WHO). Despite the high number of cases, there is currently no clinically proven drug available to inhibit the virus replication, primarily due to the limited availability of 3D crystal structures of targetable protein-protein interactions for drug activation, including the NS2B-NS3 protease from DENV2 and West Nile virus (WNV). To address this issue, docking and pharmacophore modelling have been used with the ligands from DENV2 NS2B-NS3 protease and West Nile Virus. The Systematic Literature Review (SLR) analysis identified 9 active compounds from 2 types of in vitro DENV NS2B-NS3 protease assays i.e. 21 compound classes from cell-free-based assays and 9 compound classes from cell-based assays. 2 of the 9 scaffolds' molecules were identified as the best pharmacophore model based on their high Area Under the Curve (AUC) and Enrichment Factor (EF) values, which were close to 1 and 100% respectively, and were further used as a model for pharmacophore validation.
- PublicationSynthesis, Characterisation Of Stilbene–Arylcinnamide Hybrids And Cytotoxic Studies Against Lung Cancer Cell A549(2024-07)Numerous anticancer drugs have been designed from natural products. Several compounds derived from nature such as alkaloid, flavonoid, cinnamic acid and stilbene, were reported to possess various biological properties primarily as an anticancer agent. In this study, a total of 24 compounds of a new hybrid series has been designed and synthesised, resulting from the coupling of stilbene and arylcinnamide scaffolds. All synthesised stilbene-arylcinnamide hybrids were obtained in 42-80% yield. Elucidation and characterisation of these hybrids have been validated using Fourier Transform Infrared (FT-IR), Nuclear Magnetic Resonance (NMR) spectroscopy and High-Resolution Mass Spectrometry (HRMS). The cytotoxicity against human lung cancer A549 cell line was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay, using cisplatin as the positive control. Particularly, compounds 66b and 74b have displayed potent activities on A549 cancer cells with IC50 value of 20.0 μM and 19.9 μM, respectively. This result is comparable to cisplatin with IC50 value of 19.9 μM after 72 hrs post-treatment. The structural activity relationship (SAR) analysis revealed that the presence of an isopropyl group attached to para-position of stilbene phenyl ring (ring A) of compounds 66b and 74b was crucial for a good cytotoxic effect on A549 cells. Additionally, 4-methyl group as the substituents on cinnamide phenyl ring (ring C) contributed to an innumerable cancer cell death.
- PublicationAssessment Of Knowledge, Attitude And Practices Towards Arthritis Among Nursing Students In Universiti Sains Malaysia.(2024)Arthritis and other rheumatic disorders were common diseases that caused pain, swelling, and limited mobility. They had an effect on the body's joints and connective tissue. There were over a hundred different types of arthritis, including rheumatoid arthritis, osteoarthritis, and other forms of arthritis or related disorders like gout, lupus, scleroderma, and many others. This research is aimed to assess knowledge, attitude, and practice towards arthritis among nursing students in Universiti Sains Malaysia (USM). A cross-sectional study design was conducted from 1st January 2024 to 31st March 2024 at the School of Health Sciences, USM. A total of 141 nursing students from degree and diploma were recruited via a purposive sampling method. Descriptive statistics and Pearson correlation test were used to analyse data. This study found that most of nursing students have heard about arthritis (94.3%) and their source of knowledge was from books and seminar (59%). The level of knowledge in this study showed that more participants experienced a high level of knowledge, with a mean score of 8.62 (SD = 2.36, range = 0–12). Besides, in this study mostly showed a high level of attitude, with a mean score of 22.14 (SD = 4.6, range = 0–24). The mean score for practice was 1.9 (SD = 0.12, range = 0-2), which indicates a positive practice towards arthritis. In this study, there is an association between level of knowledge and level of attitude with p- value less than 0.05 (p = 0.001), indicating that changes in knowledge levels were accompanied by corresponding changes in attitude levels. This study suggests that some basic knowledge about arthritis should be improved in order for nursing students to better understand everything related to arthritis.
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- PublicationEpitaxial Growth Of Iii-V Nitrides Based Light Emitting Diodes By Metal Organic Chemical Vapor Deposition(2023-03)This research aims to improve the performance of indium gallium nitride (InGaN) based LEDs and to demonstrate a working aluminum gallium nitride (AlGaN) based LEDs through metal organic chemical vapour deposition epitaxy. The effect of gallium nitride (GaN) nucleation growth temperature, superlattice period, and indium composition on InGaN based LED performance was studied. It was found that growing GaN nucleation at 570°C reduced threading dislocations (TDs) in the overgrown GaN layer (which served as the LED base layer). At 570°C nucleation, larger 3D growths (islands) formed, promoting dislocation inclination, and thus reducing TDs. Subsequently, 20 periods of In0.04Ga0.96N/GaN SLs led to reasonable V-pits size. This increased holes injection into the multiquantum well and hence, improved the LED performance. This research also attempted to find out factors which limit the use of GaN substrates in InGaN based LEDs development over sapphire substrates, particularly pattern sapphire substrate (PSS), which is widely used in many studies, including in this research.
- ItemMAT 101- Calculus November 2006(Universiti Sains Malaysia, 2006-11)UNIVERSITI SAINS MALAYSIA First Semester Examination Academic Session 2006/2007 October/November 2006 MAT 101- Calculus [Kalkulus] Duration : 3 hours [Masa : 3 jam] Please check that this examination paper consists of SIX pages of printed material before you begin the examination. [Sila pastikan bahawa kertas peperiksaan ini mengandungi ENAM muka surat yang bercetak sebelum anda memulakan peperiksaan ini.] Instructions : Answer all four [4] questions. [Arahan : Jawab semua empat [4] soalan.]
- PublicationMeneroka Interaksi Pelajar Terhadap Hafalan Al-qur'an Menggunakan Aplikasi Mudah Alih Berasaskan Teknik Loci, Pengulangan Jarak, Dan Pengetulan Kandungan(2022-06)Permasalahan utama yang dihadapi oleh pelajar dalam proses pembelajaran hafalan al-Qur’an di Kulliyyah Usuluddin dan Sains Qur’an (KUSQ), Universiti Islam Antarabangsa Sultan Abdul Halim Mu’adzam Shah (UniSHAMS) adalah mereka tidak dapat menyempurnakan hafalan sebanyak lima juzuk dalam setiap semester seterusnya mereka tidak akan dibenarkan mengambil peperiksaan akhir dan dikira gagal. Pencapaian hafalan pelajar dengan menggunakan kaedah konvensional adalah hanya pada tahap sederhana serta memuaskan, malah ada yang gagal dalam menyempurnakan hafalan mengikut muqarrar (silibus) yang ditetapkan, kurang bermotivasi dalam usaha melakukan hafalan, tidak dapat melakukan hafalan dengan penuh istiqamah (konsisten), mudah bosan semasa melakukan hafalan serta kurang keyakinan diri untuk melakukan proses tasmi’ (memperdengarkan) di hadapan pensyarah. Kualiti hafalan al-Qur’an adalah bergantung kepada kaedah dan proses pembelajaran yang dilakukan selain disiplin yang tinggi oleh penghafaz al-Qur’an. Kajian ini dijalankan adalah bertujuan untuk meneroka pengalaman dan persepsi pelajar menggunakan aplikasi teknologi mudah alih berbantukan teknik hafalan dan gamifikasi dalam proses hafalan al-Qur’an sebagai kaedah alternatif menggantikan kaedah konvensional pembelajaran hafalan al-Qur’an. Reka bentuk kajian ini menggunakan kaedah kualitatif dan jenis kajian kes dipilih berdasarkan sampel seramai tujuh orang pelajar Semester 1 di KUSQ, UniSHAMS
- ItemA comparison between the glidescope and the mccoy laryngoscope in manikin model with manual in-line stabilization technique.(Pusat Pengajian Sains Perubatan, 2011)Intubation of the trachea in patients with cervical spine injury is a challenging situation. Such acute trauma that requires direct laryngoscopy is accomplished with a standard manoeuvre of manual in-line stabilization technique. Unfortunately this technique creates unnecessary cause of difficult airway. Ideally intubation should be easy, fast and cause minimal cervical spine movement in cases of head and neck injury. There is a hope of indirect laryngoscopy with the GlideScope to achieve these goals. We did a study comparing the GlideScope with the McCoy laryngoscopes in manual in line stabilization (MILS) technique in manikins. This prospective and cross over study involved a total number of 4 7 participants who were anaesthetic resident. Following a brief didactic instruction on the GlideScope and the McCoy each participant took tum performing laryngoscopy and intubation with each device. They were evaluated for each device on their success rate of intubation, mean intubation time, glottic score improvement and their preferences oflaryngoscopy. We found that the success rate of intubation was 91.5% among the McCoy laryngoscope and 87.2% among the GlideScope users. Statistically these figures were not significant with p value of0.727. The McCoy laryngoscope intubations were faster than the GlideScope. The mean times of intubation were 24.4 second ±SD 15.97 and 35.3 second ±SD 17.56, respectively. The p value was significant (p value <0.001). The modified Cormack Lehane Score (CLS) in class I and II were greater with the GlideScope (72.3%) than the McCoy (46.8%). The CLS at moderate class of glottis IIIb to lila was improved for 60% and class lila to II for 73%. Among the participants, their preference of laryngoscope was almost the same where 53.2% had chosen the McCoy while another 46.8% of them favoured the GlideScope. In this study using manikins, mean intubation time was significantly faster in the McCoy group. On the other hand, the glottic score and dental trauma complications were found to be improved significantly in the GlideScope users. There was no significant difference in the success rate and easiness of intubation. Both laryngoscopes were being equally preferred among the participants. Overall, the GlideScope performance has comparable efficacy with the McCoy in this difficult airway, except it conferred greater improvement in the glottis score view. Unfortunately this did not facilitate intubation faster and easier than the McCoy. The GlideScope may be a good alternative for managing the difficult airway but clinical trials evaluating its use on patients with an actual difficult airway are needed.
- PublicationForensic profiling of proprietary pseudoephedrine precursors and oxidative products in tandem with chemometric analysis(2023-09)Pseudoephedrine (PSE) precursors are rampantly abused for the illicit production of synthetic drugs. Clandestine chemists can access this substance either from illegal sources or clandestinely extracted from proprietary formulations despite efforts from manufacturers to limit the PSE’s re-extraction. While the reduction reaction of PSE will produce methamphetamine (MA), the oxidation reaction will afford methcathinone (MET), a new psychoactive stimulant (NPS). MET is currently gaining attention as a possible replacement for MA drugs; however, there is a minimal report in the scientific literature regarding the analysis of this substance, particularly regarding its organic and isotopic profiles, which may limit the forensic community's ability to detect and regulate this substance. Initial studies involved optimisation of PSE extraction from various proprietary sources, followed by characterisation and forensic profiling of the extracted PSE products. Acid-base extraction proved to be the most viable method to obtain considerably pure PSE. Subsequently, five different sources of simulated PSE precursors were oxidised following two clandestine synthetic routes, namely chromate and manganate routes. The synthesised oxidative products were then forensically characterised, followed by an examination of their organic and isotopic profiles. Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy and gas chromatography-mass spectrometry (GC-MS) were used for organic impurity profiling, while isotope ratio mass spectrometry (IRMS) profiles 13C:12C and 15N:14N stable isotopes. The chromate and manganate routes produce compounds specific to U1 (RT 5.701, m / z 51, 77, 105, 91, and 207) and U3 (RT 9.013, m/z 70, 85, 117). Additionally, unreacted PSE was found in all the samples from the manganate route. Isotope analysis of 13C:12C and 15N:14N ratios differentiated the samples by the synthetic route and precursor sources with a nitrogen isotope, providing the best results. Data from ATR-FTIR spectra and GC-MS chromatograms were used in conjunction with chemometric analysis, namely hierarchical cluster analysis (HCA), principal component analysis (PCA), and linear discriminant analysis (LDA), to investigate the sources of precursors and the synthetic routes used. The best grouping results are obtained from LDA, where all PSE samples extracted from different sources are traced back to the source, and MET are successfully differentiated based on their synthetic routes and sources of PSE precursor used. Based on the FTIR data set, LDA recorded the correct classification rate for PSE and MET samples of 90.0% and 78.6%, respectively, while for GC-MS datasets, LDA recorded a correct classification rate of 100% for PSE and 95.2% for the MET samples. Forensic chemical profiling in tandem with chemometric analysis is beneficial in advocating the type of precursor and synthetic route used for drug manufacturing in illicit laboratories.