71 research outputs found
Development and validation of safety practices, perceived risk, risk coping and stigma questionnaire among frontline healthcare workers dealing with covid-19 pandemic in Hospital Universiti Sains Malaysia
No full textBackground: Healthcare workers (HCWs) are at higher risk of contracting COVID-19 infection compared to the general population. Safety practices, perceived risk, risk coping strategies and stigma faced by HCWs are important aspects to be investigated to ensure their wellbeing. This study aims to develop and validate Safety Practices, Perceived Risk, Risk Coping and Stigma Questionnaire among HCWs in Hospital Universiti Sains Malaysia (Hospital USM), Malaysia.
Methods: The questionnaire was generated after an extensive literature review. Content validity was done by six experts, followed by face validity with eight HCWs from the Emergency Department, Hospital USM. A cross-sectional study was done among 213 frontline HCWs directly or indirectly involved in managing COVID-19 patients in Hospital USM. Exploratory factor analysis (EFA) and reliability analysis were done.
Findings: Content validity was acceptable with item-level content validity index (I-CVI) ranging from 0.83 to 1.00 and scale-level content validity index (S-CVI) ranging from 0.85 to 1.00. Face validity was acceptable with item-level face validity index (I-FVI) ranging from 0.88 to 1.00 and scale-level face validity index (S-FVI) ranging from 0.85 to 1.00. For EFA, all factor loadings were more than 0.30. The safety practices domain was divided into three subdomains. The perceived risk domain showed three factors, the risk coping domain showed four factors, while the stigma domain revealed two factors. Cronbach’s alpha was acceptable (0.714-0.970) except for the factor dietary change under the risk coping domain which scored 0.479.
Conclusions: The Safety Practices, Perceived Risk, Risk Coping and Stigma Questionnaire is valid. All domains of this questionnaire have good reliability, except for the factor dietary change under the risk coping domain. This validated questionnaire will thoroughly assess HCWs during the COVID-19 pandemic and guide policymakers to plan appropriate interventions if required
Analysis and the methods of reducing vehicle thermal loads
No full textThis report serves as a guide to understanding and analyzing the different methods to reduce the vehicle thermal loads. The project started out with 3 objectives being defined namely to obtained the thermal loads and power requirement, to analyze the different materials used for the car and the vehicle geometry and design which can ultimately reduce this thermal heat load and finally to optimize the vehicle thermal design using all these findings. The base model used is a Nissan Leaf and as geometry was a variable in this experiment, the author generated various 3D CAD car models with varying geometry from 0° to 40° with the aid of Solidworks. The control for this experiment would be the default car model with geometry of -25°. Thermal simulations were carried out on the volume in the cabin interior and the various components via THESEUS-FE software. There was a total of 5 experiments that were be carried out to see find the optimal design that can reduce the thermal load in the vehicle in terms of geometry and materials.
The results showed that vehicles with geometry angles of 10° or more reduced the cabin temperature by about 77% which lead to a significant reduction of heat load of about 62%. The air conditioning system also consumed less power with a reduction of 34% with culminated to an improvement in fuel economy of about 2km/L. The best material which had the lowest temperature rise was found to be Poly Vinyl Chloride (PVC); as such the optimized model was a 10° geometry model that was entirely made out of PVC, which had showed that the heat load in the cabin was insignificant as compared to the default car.Bachelor of Engineering (Mechanical Engineering
Multi-cultural minds in inter and intra negotiation.
No full textNegotiation is commonplace in daily life. However, negotiation is often difficult because even the simplest negotiation is both cognitively and emotionally taxing (Carsten K. W. De Dreu & Van Kleff, 2004). In this age of the global economy, the complexity of negotiation is becoming increasingly important especially in a cross-cultural context.
Our research contributions focus, firstly, on cultural priming and its effects on individuals who possess more than one set of cultural values. This is of much relevance in the context of Singapore, a nation known for its multiracial and multiethnic citizens. Using cultural icons as the means for priming, we first carried out a preliminary test on a dozen Singaporeans to ensure the reliability of the icons before the implementation of the actual priming task. A Singapore-context negotiation task- preceded by a pre negotiation and followed by a post negotiation questionnaire, was used to test the possible influences and implications of multi-cultural minds in inter and intra negotiations. How cultural differences can affect both negotiation processes and outcomes form our second main area of interest in this study.
Findings concerning joint gains revealed new and interesting directions for further research. However, other results were not conclusive about any distinctive orientations towards specific sets of cultural values and ideals made through priming
SUSTAINING COMPETITIVE ADVANTAGE IN THE OIL PALM INDUSTRY: SWOT ANALYSIS OF IOI CORPORATION
No full textIOI Corporation, or commonly referred to as IOI, is one of Malaysia's home grown business conglomerates which started off from humble beginnings in industrial gas manufacturing. Today IOI Group is a global organization with over 150,000 hectares of plantations where 98% are planted with oil palm; 12 palm oil mills across Malaysia; three CPO refineries with total capacity of 1.8 million MT/yr located in Peninsular and East Malaysia, and Rotterdam in the Netherlands; the largest oleochemical plants in Asia; and specialty fats plants across the world in the Netherlands, the United States, Egypt, Canada, and Malaysia (source: IOI Annual Report 2009).The Group’s plantation business strong growth in a short span of 24 years since 1983 was achieved through acquisitions and distinctive plantation management practices which emphasizes on continuous improvements in yields and cost efficiencies. As a major player in the oil palm industry, which is the third biggest contributor to the Malaysian economy (,Economic Report 2007/2008), IOI corporation faces many challenges to sustain its competitiveness. What strategic moves must IOI take to remain tops in this oil palm industry? This paper seeks to provide a perspective on how IOI Corporation can sustain its competitiveness by undertaking a SWOT Analysis the corporation. A diagnosis of the corporation is made after the SWOT analysisCompetitiveness, SWOT Anlaysis, Oil palm industry, Case study
Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO)-mediated de novo synthesis of glycolate-based polyhydroxyalkanoate in Escherichia coli
No full textRibulose-1,5-bisphosphate (RuBP) carboxylase/oxygenase (RuBisCO) generates 2-phosphoglycolate (2PG) as one of the metabolites from the Calvin-Benson-Bassham (CBB) cycle. In this study, we focused on the fact that glycolate (GL) derived from 2PG can be incorporated into the bacterial polyhydroxyalkanoate (PHA) as the monomeric constituent by using the evolved PHA synthase (PhaC1(Ps)STQK). In this study, the function of the RuBisCO-mediated pathway for GL-based PHA synthesis was evaluated using Escherichia coli JW2946 with the deletion of glycolate oxidase gene (Delta glcD) as the model system. The genes encoding RuBisCO, phosphoribulokinase and 2PG phosphatase (PGPase) from several photosynthetic bacteria were introduced into E. coli, and the cells were grown on xylose as a sole carbon source. The functional expression of RuBisCO and relevant enzymes was confirmed based on the increases in the intracellular concentrations of RuBP and GL. Next, PHA biosynthetic genes encoding PhaC1(Ps)STQK, propionyl-CoA transferase and 3-hydroxybutyryl(3HB)-CoA-supplying enzymes were introduced. The cells accumulated poly(GL-co-3HB)s with GL fractions of 7.8-15.1 mol%. Among the tested RuBisCOs, Rhodosprium rubrum and Synechococcus elongatus PCC7942 enzymes were effective for P(GL-co-3HB) production as well as higher GL fraction. The heterologous expression of PGPase from Synechocystis sp. PCC6803 and R. rubrum increased GL fraction in the polymer. These results demonstrated that the RuBisCO-mediated pathway is potentially used to produce GL-based PHA in not only E. coli but also in photosynthetic organisms. (C) 2019, The Society for Biotechnology, Japan. All rights reserved
Direct Measurement of the Contents, Thickness, and Internal Pressure of Molybdenum Disulfide Nanoblisters
No full textNanoblisters have attracted attention due to their ability to controllably modulate the properties of two-dimensional materials. The accurate measurement or estimation of their properties is nontrivial and largely based on Hencky’s theory. However, these estimates require a priori knowledge of material properties and propagate large errors. Here we show, through a systematic atomic force microscopy study, several strategies that lead to vastly enhanced characterization of nanoblisters. First, we find that nanoblisters may contain both liquid and gas, resolving an ongoing debate in the literature. Second, we demonstrate how to definitively determine the membrane thickness of a nanoblister and show that Hencky’s theory can only reliably predict membrane thicknesses for small aspect ratios and small membrane thicknesses. Third, we develop a novel technique to measure the internal pressures of nanoblisters, which quantitatively agrees with Hencky’s theory but carries a 1 order smaller propagated error.Full Tex
Integration of Yolov8 and Paddleocr for car plate recognition system in diverse environments: Malaysia
No full textAn efficient car plate recognition system is significant for traffic management. However, diverse environmental factors such as poor illumination and different weather conditions, may pose challenges to car plate recognition. The efficiency of object detection and character recognition serves as a route map toward accomplishing desired outcomes within these constraints. This study devises a car plate recognition system by integrating the new variant of You-Only-Look-Once, i.e. YOLOv8, for car plate detection and PaddleOCR for extraction and recognition of the detected car plate. A self-collected database containing more than 600 car plates is collected and employed to assess the efficacy of the developed system. In this study, comprehensive experiments are carried out to assess the effectiveness of the developed system under different environmental conditions in Malaysia, including normal (day), nighttime, and rainy conditions. The empirical results exhibit the superior performance of the proposed system across diverse conditions. In conclusion, we can deduce that the proposed system is able to demonstrate robustness and reliability in car plate recognition, even under challenging environmental conditions. The integration of YOLOv8 and PaddleOCR in the car plate recognition system allows efficient detection and recognition of car plates, effectively dealing with occlusions and complex backgrounds. In future work, the system will be tested under a broader array of environmental conditions encountered in other countries, including foggy, dusty, snowfall environments, etc., to fortify its robustness in real-world scenarios. © 2025 Taylor's University. All rights reserved
Effect of losses in an active device and harmonic network on the efficiency of Class F and inverse Class F power amplifiers
No full textHigh frequency class F and inverse class F power
amplifiers obtain high efficiency of dc to ac power conversion, by reducing the overlap of voltage and current waveforms at the output of the active device, to ensure that the power dissipated in the resistance Ron of the active device is minimised. In this paper the active device is modelled as a switch in series with resistance Ron 0 to 5Ω. For ideal switch voltage / current waveforms and equal dc input power for both amplifiers the efficiency of power conversion is compared. To confirm the predicted results ideal lossless load harmonic networks using lumped elements were designed to meet all frequency conditions of the two amplifiers. These networks were done used in Advanced Design System (ADS) software for Ron=0, 2 and 4 Ω. The predicted efficiency for 2Ω and 4 Ω were 80% and 60% and the obtained simulation efficiency were 83.2% and 65.5% for class F amplifier. For the inverse class F amplifier the predicted efficiency was 87.3% and 74.5% and for the simulation results it was 87.26% and 74.4%. Above predicted and simulated results show that the resistance Ron has less effect on the efficiency of inverse class F than for class F amplifier. As lumped elements can not be used at high frequencies they were replaced initially with lossless transmission lines and then by microstrip lines to also investigate also how copper and dielectric losses affect the efficiency of power conversion
Investigation of the intrinsic mechanism of drug resistance in multiple myeloma
No full textThe focus of this thesis was to evaluate the mechanisms whereby myeloma cells develop intrinsic resistance with a focus on resistance in the context of bortezomib treatment. The aims of this thesis were to examine multidrug resistance pumps as a mechanism of resistance in MM, to investigate the contribution of p53 signalling perturbations in resistance mechanism in MM, to study the AMPK pathway as an alternative target to overcome MM resistance and finally to characterise myeloma resistance to bortezomib treatment using 2D-DIGE analysis.
Focussing on bortezomib resistance models, we found that that overexpression of P-gp attenuates bortezomib activity. Bortezomib is a P-gp substrate and a combination of P-gp inhibitor and bortezomib is able to overcome resistance. Bortezomib is also able to downregulate the expression and function of P-gp. Our findings therefore suggest that combination of a P-gp inhibitor and bortezomib in P-gp positive myeloma would be a reasonable treatment combination to extend use of the drug.
We have shown that p53 apoptotic signalling pathways can be accentuated when bortezomib is combined with a Mdm2 inhibitor. In p53 WT cells, nutlin-3 in combination with bortezomib generates additive toxicity in MM cells but is highly synergistic in epithelial models and p53-mutated cell lines. This synergy persists in the presence of BMSCs. This observation has implications more so in epithelial cancers and p53 mutated cancers where single agent bortezomib activity is mild. We have also shown that bortezomib-treated patients who had high expression of nutlin-3-suppressed genes had significantly shorter progression-free (p=0.001, log-rank test) and overall survival (p=0.002, log-rank test) compared to those with low expression levels.
AMPK activation is promising as an anticancer pathway and may also be a chemoprevention target. Metformin and AICAR, which activate this pathway, both have demonstrated useful preclinical anticancer properties and have a good therapeutic index in patients. We explored mechanism of cell death and showed that AICAR was able to activate the apoptotic pathway. These agents also synergise with glycolysis inhibitors to further increase cytotoxicity in cancer cells.
Identification of proteins whose expression is altered in differing states of sensitivity and resistance provides candidates for better understanding of resistance mechanisms so we also investigated bortezomib resistance in cellular models using proteomic techniques and isolated and identified several novel proteins which may play a role in this phenomenon. Our findings are mechanistically consistent since two of the identified proteins Hsp70 and caspase-3 are known in the literature to be affected by bortezomib treatment
Patterns of sex worker-client contacts and their implications for the persistence of sexually transmitted infections.
No full textSex workers (SWs) and their clients are often identified as being central in transmission of sexually transmitted infections (STIs). Little is known about how patterns of contact between SWs and their clients influence the persistence of STIs. We developed an individual-based simulation model to explore how variation in number of client contacts per SW, whether clients repeatedly visited the same SW, and the relative sizes of the SW and client populations influence the endemic prevalence of gonorrhea and herpes simplex virus type 2 infection. Persistence of either infection was more likely if clients visited many different SWs, regardless of variation in the SW-client contact rate, and also resulted in a higher endemic prevalence in both populations and a greater likelihood of persistence of infection at lower levels in the general population. The size of the SW population (relative to the total population) was found to be most important in determining the overall prevalence of infection
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