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- PublicationThe mapping of danger zone for suprapectineal screw placement in quadrilateral plate osteosynthesis using 3D printed model(2022)Introduction Open reduction and internal fixation (ORIF) are the gold standard treatment for acetabular injuries, despite risk of intra-articular screw placement where prevention is dependent on intra-operative use of image intensifier and three-dimensional (3D) imagination capacity of the surgeon. There is sparse documentation on safe zones for screw placement at the supra-pectineal region despite it being a common area encountered during osteosynthesis. This study aims to define the safe zones for screw placement at the supra-pectineal region and propose screw trajectories with the help of 3D printed model of the pelvis. Methodology This is a retrospective study using computed tomography (CT) pelvis images from patient’s records in Hospital Universiti Sains Malaysia (HUSM). The inclusion criteria include 18 to 60 years at the time of Computed Tomography (CT) scan regardless of gender. CT scans reported to have abnormalities, pathology or prior instrumentations were excluded from the study. Extracted CT images undergo multistep process of fragmentation and slicing to produce file format which can be 3D printed using the Creality CR-6 max FDM 3D printer. Measurements of the absolute and relative danger zones, as well as the minimal posterior inclination angle were measured. All analyses were conducted using IBM SPSS Statistics 26. The statistical analyses that were used in this study were descriptive statistics and an Independent t-test. Results A total of 30 CT scans were used in this study. The mean (SD) age of patients was 33.50(13.08) years old. A total of 20 scans (66.7%) belonged to male patients, and 10 scans (33.3%) belonged to female patients. Mean difference between gender was statistically significant for length AC (P<0.05) where male patients (Mean=4.89, SD=0.33) lengths were higher than female patients (Mean=4.40, SD=0.47). There were no significant mean differences in other parameters investigated. Conclusion Defining absolute and relative danger zones together with ascertaining safe juxta-articular screw trajectory had made this study a guide for surgeons endeavouring on pelvic or acetabular surgery with the aim of reducing incidence of intra-articular screw insertion, decreasing surgical time, and reducing dependence on image intensifier.
- PublicationImpact of covid-19 infection on maternal and fetal outcome in Hospital Sungai Buloh from 2020-2021(2022)OBJECTIVE: To study the impact of Covid-19 infection on maternal and fetal outcome in Hospital Sungai Buloh. This study was also done to determine factors affecting maternal morbidity in patients with Covid-19 infection in the of presence symptoms and obesity. METHODOLOGY: A retrospective study was conducted at O&G department HSB for a period of 1 year from 1st March 2020 till 1st March 2021 involving 332 pregnant mothers infected with covid-19 infection and babies born which fulfilled the inclusion and exclusion criteria. RESULTS: There were less adverse maternal and fetal outcomes. As for maternal outcome, rate of LSCS was 19.9% (n =66), ICU admission was only 4.5% (n=15), patients requiring mechanical ventilation was 2.4% (n=8) and no maternal death. As for fetal outcome rate preterm delivery was 4.2% (n= 14), low birth weight rate was 3.6% (n=12), stillbirth was 0.9% (n=3), low Apgar Score 3.3% (n=11) and no vertical transmission. However, symptomatic patient had significant association with maternal ICU admission with a likelihood of 32.72 (Adj 95% CI (4.18,256.48), p=0.001. In addition, obese patient has no significant association with maternal ICU admission. CONCLUSION: Although pregnancy increases the susceptibility to complications of Covid-19 infection due to physiological and immunological changes, from this study we found that those pregnant women with Covid-19 who attended HSB experienced less maternal and fetal outcomes such as increased LSCS rates, maternal ICU admission, mechanical ventilation and maternal death, preterm birth, low birth weight, low Apgar score and still birth. However, symptomatic patients had a significant association with maternal ICU admission. This should alert clinicians to identify those who are at risk especially symptomatic to seek treatment earlier and to strictly implement all the recommended preventive measures.
- PublicationProportion of non-deletional alpha thalassaemia in Hospital Tengku Ampuan Rahimah (HTAR), Klang, Selangor(2022)Introduction: Alpha (α) thalassaemia, caused by deletional and non-deletional mutations of the α-globin gene, is one of the most common haemoglobin genetic abnormalities. Non-deletional determinants of alpha thalassaemia produces highly unstable variants which are difficult to detect and may lead to HbH disease or even haemoglobin Bart hydrops fetalis syndrome when compounded with deletional mutations. Objective: This study aims to provide data on the proportion of non-deletional alpha thalassaemia at Hospital Tengku Ampuan Rahimah (HTAR), Klang, Selangor, to compare the haematological parameters (Hb, RBC, MCH, MCV, MCHC) of non-deletional alpha thalassaemia with the deletional variant and to determine the agreement between Capillary Electrophoresis and High-Performance Liquid Chromatography in detecting non-deletional alpha thalassaemia established by molecular analysis. Methods: A cross-sectional study involving data extraction from the HTAR haematology laboratory registry on confirmed thalassaemia cases via DNA analysis from January 2017 to December 2019. Haematological parameters and haemoglobin analysis results were obtained from the laboratory database. Samples were segregated into three groups according to the number of mutated genes. Results: We identified a total of 479 cases of alpha thalassaemia, from which 98 (20.5%) were non-deletional type. Among these, 75 (76.5%) were heterozygous Hb CS, 17 (17.3%) heterozygous Hb Adana, 3 (3.1%) heterozygous Hb QS and 1 (1.0%) case each of compound heterozygous Hb CS and Hb Adana (αCSα/αCD59α), compound heterozygous Hb CS and -3.7kb deletion (αCSα /-α3.7) and compound heterozygous of Hb CS and SEA deletion (αCSα/--SEA). In the single and double gene mutated groups, there was no significant difference of haematological parameters between both variants. In the third group, due to the very small number of sample size, statistical analysis was not done. Among the non-deletional variants, there was significant association between Hb, MCH and MCHC parameters and the number of mutated alpha genes. A total of 77 samples out of the 98 non-deletional cases showed positive findings on CE. However, of these 77 samples, only 40 samples underwent HPLC as the second screening method of haemoglobin analysis and from which 5 (12.5%) samples were detected by HPLC. Conclusion: This study showed that Hb CS is the most common non-deletional α thalassaemia in HTAR, Klang. We identified that Hb, MCH and MCHC may help as an effective screening tool for non-deletional alpha thalassaemia. We also revealed that there is a significant association between CE and HPLC in detecting Hb CS, and that CE is superior to HPLC.
- PublicationIn Vitro Antibacterial Activity Of Acanthus Ilicifolius-silver Nanoparticles Against Selected Bacteria(2018)Silver nanoparticles (AgNPs) has gained attention due to their wide application in various area such as medical, food industry and material sciences. Among medical uses of this nanoparticles is as antimicrobial agent against pathogenic bacteria. AgNPs produced by green biosynthesis approach using plant extracts as reducing agent is less harmful and economical in comparison with physical and chemical methods. In this study, plant material was collected and identified as Acanthus ilicifolius Wallich, N and was being used to prepare the plant aqueous extract which later being used to synthesis AgNPs. Ratio of 1: I 0 mixtures of I 00 mg/mL of aqueous extract and 5 mM of si lver nitrate was incubated for 24 hours at 40 °C with 150 rpm in incubator shaker.The formation of silver nanoparticles was monitored by colour changes and was characterised by UV-Vis spectrometry fo llowed by zeta (potential) sizer analyses. The UV-Vis spectrum of AgNPs showed maximal absorption at 440 while zeta (potential) sizer analyses revealed the average size of synthesized AgNPs was 94 nm with zeta potential value of -4.08 mV which the AgNPs quite unstable. Antibacterial activities of synthesised A. ilicifolius-AgNPs by well diffusion method on S. aureus, B. cereus, E. coli and P. aeruginosa showed an inhibition zone (in millimeter, mm) of 16, 15, 14 and 20 respectively. Minimal inhibitory concentration (MIC) as well as minimal bactericidal concentration (MBC) of this si lver nanoparticles accessed by MTT assay was lower than 0.0781 25 mM on all tested bacteria. Therefore, it is concluded that A. ilicifolius aqueous extract has potential in producing AgNPs by green synthesis approach and may be used as antibacteria l agent against parti cularly on S. aureus, B. cereus, E. coli and P. aeruginosa
- PublicationEffect Of Salivary pH On Coating Durability Of Two Different Aesthetic Archwires Coatings(2018)Coated orthodontic archwires have demonstrated partial or full coating loss as early as 21 days of intraoral use. It is suggested that an interaction between the coated archwires and the oral factors such as salivary pH has caused this phenomenon to occur. This study evaluated the effect of pH on the durability of two different aesthetic archwire coatings and observed the surface topography of the coatings. Nickel titanium (NiTi) archwires of 0.0 18" in diameter, readi ly coated with epoxy resin and polytetrafluoroethylene (PTFE) were sectioned into 20 mm segments. All specimens (N = I 02) were divided into six groups; four groups treated with two different pH and two control groups. The pH of artific ial saliva was adjusted to 6.75 and 3.5 using sodium hydrox ide (NaOH) and lactic acid, respectively. Each specimen was immersed in individual test tubes containing 10 ml of modified solution which were sealed and stored in a 37°C water bath for 28 days.After the time elapsed, the specimens were removed and subjected to mechanical stress using an electronic toothbrush for 2 10 seconds. Images were photographed us ing digital single lens reflex (DSLR) camera and coating loss measurement was done using Autodesk® AutoCAD® software. Surface topography of the specimens from each group was evaluated using scann ing electron microscope (SEM). Statistical analysis showed significant (p < 0.001) coating loss was found in epoxy res in groups regardless of their pH value, than that of PTFE groups. SEM revealed rupture, roughness and loss of coating at mult iple locations on the coating s urface.
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- PublicationEffects of graphene oxide coating on the properties of polyurethane nanofiller nanocomposite foams(2022-08-22)In this study, carbon black (CB) and multiwalled carbon nanotube (MWCNT) were used as fillers for the preparation of the polyurethane (PU) nanocomposite foams. The CB and MWCNT loadings were in the range of (1, 2.5, 5, 7.5 phr). Further, graphene oxide (GO) coating was applied on the surface of the PU/CB and PU/MWCNT nanocomposite foams to increase the electrical conductivity which is determined by the surface resistance. The properties of the PU nanocomposite foams were characterised using foam density measurement, scanning electron microscopy (SEM), and surface resistance tests. The foam density of the PU was increased as a result of the increasing loading of CB or MWCNT. Furthermore, the PU/MWCNT nanocomposite foam has a higher density than the PU/CB nanocomposite foam at the same nanofiller loading. The microstructure analysis of the PU nanocomposite foams found that the average cell size is reduced as the filler loading increases. This indicates that the CB and MWCNT can act as cell nucleation sites to promote cell growth. The surface resistance of PU/MWCNT nanocomposite foam is lower than that of PU/CB nanocomposite foams at the same filler loading. Interestingly, the surface resistance of PU nanocomposite foams (formulation PU-MWCNT-5wt%) decreases from 5.8 x 1010 Ω to 1.7 x 108 Ω by the GO coating. This indicates that the GO coating is capable of increasing the electrical conductivity of the PU nanocomposite foam. Overall, the PU nanocomposite foam with dissipative behaviour was successfully produced using a combination of filler (dispersed in the PU matrix) and GO coating method.
- PublicationMapping temperature distribution during 3d printing process of post consumer high density polyethylene(2025-08-11)This study explores the use of 100 % post-consumer HDPE (PC-HDPE) compounded with 30 phr kaolin clay as filament for Fused Deposition Modeling (FDM). The aim of this project is to map real-time thermal distributions during FDM of PC-HDPE with 30 phr Kaolin filler (PC-HDPE/30) and identify nozzle size (0.4 and 0.6 mm), nozzle temperature (200, 220, 240, 260 °C) and bed temperature (60, 70, 80, 90 °C) that minimize shrinkage and warpage. Post-consumer HDPE flakes obtained from shredding of detergent bottles were cleaned, compounded with kaolin clay via a heated two-roll mill, and extruded into 1.75 mm filament. A Creality Ender-3 printer was equipped with an InfiRay T2S Plus thermal camera to map temperatures at the nozzle exit, bead, and build plate. A 4×4×2 full factorial design with three replicates was used to vary nozzle temperature, bed temperature, and nozzle size, shrinkage was calculated from CAD-to-printed volume differences, warpage was measured from average corner heights and all data were analyzed by ANOVA (α = 0.05) in Minitab 18. Based on data obtained and ANOVA analysis, the deposited temperature was highly sensitive to all main effects (P < 0.05). Shrinkage showed a significant interaction between nozzle and bed temperatures (P = 0.009), though neither factor alone was significant. Warpage was significantly influenced by nozzle temperature, bed temperature, and nozzle size (all P < 0.05), with a notable nozzle‑size × nozzle‑temperature interaction. A nozzle temperature of 220–240 °C, a bed temperature of 70–80 °C, and a 0.6 mm nozzle were recommended to minimize shrinkage and warpage.
- ItemPeperiksaan Perkhidmatan Pembantu Setiausaha Pejabat N19 Kertas II : 2 Mei 2019(Universiti Sains Malaysia, 2019-05-02)Tarikh : 2 Mei 2019 (Khamis) Masa : 9.00 Pagi – 11.00 Pagi (2 Jam) Tempat : Kampus Induk & Kampus Kesihatan
- ItemThe Performance Management Of An Externally Imposed Programme: The Case Of A Governmental Organisation(Universiti Sains Malaysia, 2017-08)The main aim of this study is to understand and explain how the AZAM Tani programme was implemented in the case organization, as well as how it was being considered into its performance management system (PMS) given that the organization had been entrusted by the Malaysian government to achieve two different main objectives (i.e. advancing the marketing of agri-food products and improving the living standard of the low income households). Furthermore, the study explains how the externally derived objective vertically coupled among the three hierarchical levels (top, middle, operational level) within the organization, as well as the coupling between the intention and action in relation to the programme. The study employed an interpretative case study method, whereby data were collected through semi-structured interviews with various officers from top, middle and operational levels. Documents were also reviewed to support the generated data from the interviews. The finding of the study is informed by Neo-Institutional Sociology perspective as the theory indicates that an organisation adopts new practices not only due to economic or functional factors, but also because of institutional factors. From the finding, it is revealed that the organisation accepted the programme as a result of coercive pressure from the government. Consequently, the programme was found to be loosely coupled with the organisation’s activities as compromise strategy was employed in the implementation of the programme. The consideration of the programme into the organization’s PMS system was loosely coupled, reflected by its integration in terms of its performance measurement and reporting activities. A further investigation on the implementation of the programme revealed that there are some interdependency between the three hierarchical levels in terms of its performance measures and targets, responsibilities and reporting. However, there were no significant changes to the organisation’s practices thus providing evidence of vertical loose coupling. Horizontal loose coupling was also found as there are poor linkages between the programme’s result orientation, the development of its performance indicators and the usage of its performance information assessment. Since the action of the organisation is limited to the activities of performance measurement and reporting, the implementation of the programme was considered as ceremonial implementation. On overall, the study reveals that the implementation of the programme in the case organization is mainly designed to report on success as the directives, key performance indicators and targets were predetermined and were enforced top down.
- ItemDetermination Of Fracture Toughness In PBGA Packages Using Finite Element And Experimental Methods(Universiti Sains Malaysia, 2006-11)Electronic packages especially the plastic ball grid array (PBGA) has its unique crack failure arising from the soldering process. The existence of moisture absorbed in package from ambient condition causes vapor pressure. During reflow soldering processes (215°C), the moisture absorbed vaporizes and eventually causes popcorn cracking. So, numerical method is used to characterize the fracture resistance in terms of geometric stress intensity factor (SIF). Then, the investigation of fracture toughness on epoxy molding compound (EMC) material provided boundary conditions of package cracking. In this research, Ansys software was used to simulate moisture diffusion and thermal transfer to determine the vapor pressure at the crack region. The vapor pressure loading was applied on PBGA to obtain geometric SIF using modified crack closure integral (MCCI) method. It was found that the increased in vapor pressure and higher delamination size created high geometric SIF. Load-crack edge extension relation obtained from holographic interferometry (HI) method and critical load for D.E.R. 331 as EMC material were used to evaluate fracture toughness. The fracture toughness for D.E.R 331 was found to be 0.488MPa m 1/2. Eventually, the fracture toughness for D.E.R. 331 was compared with PBGA's geometric SIF. A graph with package safety conditions was obtained. From the graph, it can be concluded that the PBGA is typically to be saved during soldering process, where vapor pressure is 1.21 MPa and delarnmatron ratio is less than 0.6. This EP's failure can be controlled through minimizing the effect of vapor pressure and reducin_g die/EMC interface delamination