Universiti Sains Malaysia
  • George Town, Pulau Pinang, Malaysia
Recent publications
Objectives: Early access to innovative oncology medicine is crucial to provide better treatment alternatives to patients with cancer. However, innovative oncology medicines often come at higher prices, thus limiting the government’s ability for its universal coverage. Hence an alternative paying mechanism is needed. This study is intended to determine the willingness to pay (WTP) for innovative oncology medicines among Malaysians. Methods: A cross-sectional contingent valuation study on 571 Malaysians was conducted to elicit respondents’ WTP value via bidding game approach. A double-bounded dichotomous choice was used in 3 hypothetical scenarios: innovative diabetes medicine, innovative oncology medicine one-off (IOMO), and innovative oncology medicine insurance. Univariate logistic regression was used to determine the factors affecting respondent’s WTP, whereas the mean WTP value and the factors affecting amount to WTP was determined using a parametric 2-part model. Results: This study received 95% response rate. The mean age of the respondents is 48 years (SD 17) with majority of the respondents female (60.3%) and from ethnic Malay (62%). About 343 (64.7%) of the respondents expressed WTP for IOMO. Those in higher income bracket were willing to pay more for the access of IOMO than the overall WTP mean value (P = .046, coefficient 351.57). Conclusions: More than half of Malaysian are willing to pay for IOMO at mean value of Malaysian Ringgit 279.10 (US dollar 66.77). Collaborative funding mechanisms and appropriate financial screening among the stakeholders could be introduced as methods to expedite the access of innovative oncology medicine among patients with cancer in Malaysia.
Impairment of fish growth and immune system due to stress and disease are major constraints in aquaculture industry. Traditionally, antibiotic was used as prophylactic agent in the health management of aquaculture species. However, antibiotic only provide a temporary solution to the problem of disease outbreak. Over-reliance on antibiotic also has led to the increasing cases of antibiotic resistance among pathogenic bacteria from aquaculture sites and contamination of antibiotic residues into human food chain. Probiotic, prebiotic and symbiotic are therefore suggested as alternatives to prophylactic antibiotic to be used in the aquaculture industry. A potential prophylactic agent is polysaccharide that could be developed into an alternative antibiotic for aquatic animals. In this review paper, definition, sources, and mode of action of polysaccharide are presented. The roles of polysaccharides in fish farming with emphasis on growth improvement, immune system enhancement, disease resistance stimulation in tilapia farming, and the effects of polysaccharides on abiotic stressors are summarized and discussed.
Biofertilizers encompass microorganisms that can be applied to plants, subsequently establishing themselves within the plant's rhizosphere or internal structures. This colonization stimulates plant development by enhancing nutrient absorption from the host. While there is growing literature documenting the applications of microalgae-based and bacterial-based biofertilizers, the research focusing on the effectiveness of consortia formed by these microorganisms as short-term plant biofertilizers is notably insufficient. This study seeks to assess the effectiveness of microalgae-bacterial biofertilizers in promoting plant growth and their potential contribution to the circular economy. The review sheds light on the impact of microalgae-bacterial biofertilizers on plant growth parameters, delving into factors influencing their efficiency, microalgae-bacteria interactions, and effects on soil health. The insights from this review are poised to offer valuable guidance to stakeholders in agriculture, including farmers, environmental technologists, and businesses. These insights will aid in the development and investment in more efficient and sustainable methods for enhancing crop yields, aligning with the Sustainable Development Goals and principles of the circular economy.
Background Colistin is an antibiotic used as a last-resort to treat multidrug-resistant Gram-negative bacterial infections. Colistin had been used for a long time in veterinary medicine for disease control and as a growth promoter in food-producing animals. This excessive use of colistin in food animals causes an increase in colistin resistance. This study aimed to determine molecular characteristics of colistin-resistant Escherichia coli in broiler chicken and chicken farm environments. Results Four hundred fifty-three cloacal and farm environment samples were collected from six different commercial chicken farms in Kelantan, Malaysia. E. coli was isolated using standard bacteriological methods, and the isolates were tested for antimicrobial susceptibility using disc diffusion and colistin minimum inhibitory concentration (MIC) by broth microdilution. Multiplex PCR was used to detect mcr genes, and DNA sequencing was used to confirm the resistance genes. Virulence gene detection, phylogroup, and multilocus sequence typing (MLST) were done to further characterize the E. coli isolates. Out of the 425 (94%; 425/453) E. coli isolated from the chicken and farm environment samples, 10.8% (48/425) isolates were carrying one or more colistin-resistance encoding genes. Of the 48 colistin-resistant isolates, 54.2% (26/48) of the mcr positive isolates were genotypically and phenotypically resistant to colistin with MIC of colistin ≥ 4 μg/ml. The most prominent mcr gene detected was mcr-1 (47.9%; 23/48), followed by mcr-8 (18.8%; 9/48), mcr-7 (14.5%; 7/48), mcr-6 (12.5%; 6/48), mcr-4 (2.1%; 1/48), mcr-5 (2.1%; 1/48), and mcr-9 (2.1%; 1/48) genes. One E. coli isolate originating from the fecal sample was found to harbor both mcr-4 and mcr-6 genes and another isolate from the drinking water sample was carrying mcr-1 and mcr-8 genes. The majority of the mcr positive isolates were categorized under phylogroup A followed by phylogroup B1. The most prevalent sequence typing (ST) was ST1771 ( n = 4) followed by ST206 ( n = 3). 100% of the mcr positive E. coli isolates were multidrug resistant. The most frequently detected virulence genes among mcr positive E. coli isolates were ast (38%; 18/48) followed by iss (23%; 11/48). This is the first research to report the prevalence of mcr-4, mcr-5, mcr-6, mcr-7, and mcr-8 genes in E. coli from broiler chickens and farm environments in Malaysia. Conclusion Our findings suggest that broiler chickens and broiler farm environments could be reservoirs of colistin-resistant E. coli , posing a risk to public health and food safety.
As this unmanned aerial vehicle (UAV) has a planned airframe that can carry a 25 kg payload, understanding its structural capabilities, such as its compressive and tensile strengths under different situations, is essential. For the purpose of comprehending the fluid–structure interaction (FSI) of the fuselage, this study designs and analyses the lightweight materials used in the airframe of a complex Gyrodyne UAV. A computer model of a composite airframe for a Gyrodyne UAV is built to examine its durability. An essential factor in the aircraft business is minimizing unnecessary weight, and this FSI study emphasizes the importance of sandwiches and their hybrid combinations in this regard. After the material finalization, around 140 material combinations are tested using an advanced computational composite platform, in which four different lightweight material families are implemented. The fluid load (pressure) is imported into ANSYS workbench 17.2, and the structural airframe is then solved according to the boundary conditions of the application domain. Also, experimental experiments using the high-speed jet facility are run to verify computational improvements. Materials for the airframe of the Gyrodyne UAV have been narrowed down to a final list of contenders. As the work focuses on the FSI analysis, not much computational fluid dynamics (CFD) results were discussed here. Only the imported pressure from the CFD analysis was imposed on to the Gyrodyne UAV to proceed for the FSI analysis.
The paper examines pre-combustion carbon capture technology (PreCCS) for liquefied natural gas (LNG) propelled shipping from thermodynamics and energy efficiency perspectives. Various types of LNG reformers and CCS units are considered. The steam methane reformer (SMR) was found to be 20% more energy efficient than autothermal (ATR) and methane pyrolysis (MPR) reactors. Pressure swing adsorption (PSA) had a lower energy requirement than membrane separation (MEM), cryogenic separation (CS), and amine absorption (AA) in pre-combustion carbon capture, with PSA needing 0.18 kWh/kg CO2. An integrated system combining SMR and PSA was proposed using waste heat recovery (WHR) from the engine, assuming similar efficiency for LNG and H2 operation, and cooling and liquefying of the CO2 by the LNG. The SMR-PSA system without WHR had an overall efficiency of 33.4% (defined as work at the propeller divided by the total LNG energy consumption). This was improved to 41.7% with WHR and gave a 65% CO2 emission reduction. For a higher CO2 reduction, CCS from the SMR heater could additionally be employed, giving a maximum CO2 removal rate of 86.2% with 39% overall energy efficiency. By comparison, an amine-based post-engine CCS system without reforming could reach similar CO2 removal rates but with 36.6% overall efficiency. The advantages and disadvantages and technology readiness level of PreCCS for onboard operation are discussed. This study offers evidence that pre-combustion CCS can be a serious contender for maritime propulsion decarbonization. Graphical Abstract
Objective Since unexpected COVID-19 has been causing massive losses worldwide, preventive measures have been emergency provided to curb the expansion of the epidemic and cut off transmission routes. However, there is a lack of studies that comprehensively address COVID-19 infection prevention measures. This aims to provide a comprehensive evaluation framework to identify the factors impacting COVID-19 infection prevention. Meanwhile, categorizing factors into individual, social, environmental, and technological dimensions and uncovering their interrelationships and level of importance are indeed novelties of this study. Methods An integration of fuzzy logic and decision-making trial and evaluation laboratory (DEMATEL) is utilized, and data was collected from a panel of professional experts in Malaysia. Using a cause-effect relationship diagram, the fuzzy DEMATEL method evaluates the causal relationships between factors. Results Findings showed that environmental factors play the most significant roles in preventing COVID-19 infection, followed by technology, individual, and social factors. Getting vaccinated is the most crucial factor in the environmental dimension in cutting the spread of COVID-19. Telehealth, the use of personal protective equipments (PPEs), and the adoption of social distancing are the most important measures in technology, individual and social dimensions, respectively. Conclusions This study offered valuable insights for policymakers and healthcare professionals in designing and implementing effective strategies to prevent pandemic disease transmission. Findings can be practically applied to optimize and prioritize infection prevention measures, assign resources more effectively, and guide evidence-based decision-making in the face of evolving pandemic situations. This process involves the active commitment of all parties, including governments, medical health executives, and citizens.
Erectile dysfunction (ED) is a pervasive problem among men, often shrouded in silence and stigma. This manuscript analysed the National Health and Morbidity Survey 2019 data to identify the prevalence of moderate to severe ED among men aged 18 and above in Malaysia and describe its associated factors. Self-administered questionnaire on ED utilised a locally validated International Index of Erectile Function. Variables on sociodemographics, risky lifestyles and comorbidities were obtained via an interviewer-administered questionnaire. The prevalence was determined using complex sampling analysis, and logistic regression was used to determine the associated factors of ED. A sample of 2403 men aged ≥ 18 participated, with a moderate to severe ED prevalence was 31.6% (95% CI 28.8, 34.6). The mean (± SD) of the total score of IIEF-5 for overall respondents was 18.16 (± 4.13). Multiple logistic regression analysis revealed a significant association between moderate to severe ED among men aged 60 years and above, single or divorcee, men without formal, primary, and secondary education, non-government employees, unemployed, and retiree, as well as physically inactive men. Focused public health interventions are necessary to improve education in sexual health, increase health promotion programs, and promote healthy ageing across the population.
Driver behavior refers to the actions and attitudes of individuals behind the wheel of a vehicle. Poor driving behavior can have serious consequences, including accidents, injuries, and fatalities. One of the main disadvantages of poor driving behavior is the increased risk of road accidents, higher insurance premiums, fines, and even criminal charges. The primary aim of our study is to detect driver behavior early with high-performance scores. The publicly available smartphone motion sensor data is utilized to conduct our study experiments. A novel LR-RFC (Logistic Regression Random Forest Classifier) method is proposed for feature engineering. The proposed LR-RFC method combines the logistic regression and random forest classifier for feature engineering from the motion sensor data. The original smartphone motion sensor data is input into the LR-RFC method, generating new probabilistic features. The newly extracted probabilistic features are then input to the applied machine learning methods for predicting driver behavior. The study results show that the proposed LR-RFC approach achieves the highest performance score. Extensive study experiments demonstrate that the random forest achieved the highest performance score of 99% using the proposed LR-RFC method. The performance is validated using k-fold cross-validation and hyperparameter optimization. Our novel proposed study has the potential to revolutionize the early detection of driver behavior to avoid road accidents.
Purpose This study aims to determine the percentage depth dose (PDD) of a phantom material made from soy-lignin bonded Rhizophora spp. particleboard coated with a gloss finish by using Monte Carlo Geant4 Application for Tomographic Emission (GATE) simulation. Materials and Methods The particleboard was fabricated using a hot pressing technique at target density of 1.0 g·cm ⁻³ and the elemental fraction was recorded for the simulation. The PDD was simulated in the GATE simulation using the linear accelerator Elekta Synergy model for the water phantom and Rhizophora phantom, and the results were compared with the experimental PDD performed by several studies. Beam flatness and beam symmetry were also measured in this study. Results The simulated PDD for Rhizophora and water was in agreement with the experimental PDD of water with overall discrepancies of 0% to 8.7% at depth ranging from 1.0 to 15.0 cm. In the GATE simulation, all the points passed the clinical 3%/3 mm criterion in comparison with water, with the final percentage of 2.34% for Rhizophora phantom and 2.49% for the water phantom simulated in GATE. Both the symmetries are all within the range of an acceptable value of 2.0% according to the recommendation, with the beam symmetry of the water phantom and Rhizophora phantom at 0.58% and 0.28%, respectively. Conclusions The findings of this study provide the necessary foundation to confidently use the phantom for radiotherapy purposes, especially in treatment planning.
Background and aim Primarily, this study compares the efficacy of probiotic and acceptance and commitment therapy (ACT) in alleviating the severity of alcohol craving and alcohol use disorder (AUD) among patients who had undergo two weeks of in-patient detoxification. Secondarily, this study compares the efficacy of probiotic and ACT in mitigating the severity of comorbid depression and anxiety symptoms; decreasing serum level of pro-inflammatory cytokines, such as interleukin 1β (IL-1β), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α); changing the event-related potential in electroencephalogram (EEG) and restoring microbiota flora in the gut of AUD patients. Methods and analysis Initially, during Phase I of the study, the serum level of IL-1β, IL-6 and TNF-α; ERP changes in the EEG and fecal microbiota content will be compared between 120 AUD patients and 120 healthy controls. Subsequently in Phase II of the study, 120 AUD patients will be randomized by stratified permuted block randomization into the probiotic, ACT and placebo groups in a 1:1:1 ratio. Participants in the probiotic and placebo groups will be administered one sachet per day of Lactobacillus spp . probiotic and placebo, respectively for 12 weeks. While those in the ACT group will receive one session per week of ACT for 8 weeks. Outcome measures will be administered at four timepoints, such as t 0 = baseline assessment prior to intervention, t 1 = 8 weeks after intervention began, t 2 = 12 weeks after intervention and t 3 = 24 weeks after intervention. Primary outcomes are the degrees of alcohol craving, alcohol withdrawal during abstinence and AUD. Secondary outcomes to be assessed are the severity of co-morbid depression and anxiety symptoms; the serum levels of IL-1β, IL-6 and TNF-α; changes in ERP and fecal microbiota content. Trial registration number NCT05830708 (ClinicalTrials.gov). Registered on April 25, 2023.
This study takes the landscape space of traditional Tibetan villages in western Sichuan as the research object, and three national-level traditional villages of different Tibetan clans in Gyatso, Amdo and Baima Tibet were selected as samples. Using the fractal theory, combined with counting-box dimension measurement and spatial analysis methods, it comparatively analyzes the fractal characteristics of their landscape space and their influencing factors. The study finds that the landscape space of these villages has certain fractal characteristics, which are characterized by self-similarity and irregularity. The fractal characteristics of different villages are influenced by various factors such as geographic location, natural conditions, religious beliefs, folk costumes, etc., showing differences and diversity. There is a certain correlation between the fractal dimension and the distribution of landscape elements and spatial patterns, which can be used to describe the complexity and diversity of landscape space pattern. The article believes that the fractal theory provides a new perspective and method for analyzing the landscape space of traditional Tibetan villages, which helps to reveal its intrinsic formation mechanism and cultural connotation and provides new insights for the protection of traditional village heritage and the maintenance of cultural traditions. Meanwhile, the study also points out the limitations and shortcomings of the fractal theory in the study of traditional villages and puts forward directions and suggestions for future research.
Background Lifestyle modifications involving diet and exercise are recommended for patients diagnosed with obesity and type 2 diabetes mellitus (T2DM). The purpose of this review was to systematically evaluate the effects of combined aerobic exercise and diet (AEDT) on various cardiometabolic health-related indicators among individuals with obesity and T2DM. Methodology A comprehensive search of the PubMed/Medline, Web of Science, Scopus, Science Direct, Cochrane, and Google Scholar databases was conducted for this meta-analysis. The Cochrane risk of bias tool was used to evaluate eligible studies, and the GRADE tool was used to rate the certainty of evidence. A random-effects model for continuous variables was used, and the results were presented as mean differences or standardised mean differences with 95% confidence intervals. Results A total of 16,129 studies were retrieved; 20 studies were included, and data were extracted from 1,192 participants. The findings revealed significant improvements in body mass index, body weight, waist circumference, systolic blood pressure, diastolic blood pressure, total cholesterol, triglycerides, fasting blood glucose, fasting plasma insulin, glycated hemoglobin, leptin, interleukin-6, C-reactive protein, and adiponectin (p < 0.05) compared to the standard treatment (ST) group. No significant differences were observed between the AEDT and ST groups in fat mass, hip circumference, waist-to-hip ratio, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and tumor necrosis factor-alpha. The present findings are based on low- to moderate-quality evidence. Conclusions AEDT may be a critical behavior for holistic cardiometabolic health-related benefits as a contemporary anti-obesity medication due to its significant positive impact on patients with obesity and T2DM. Nevertheless, further robust evidence is necessary to determine whether AEDT is an effective intervention for lowering cardiovascular and metabolic risk factors among individuals with obesity and T2DM.
The spatiotemporal accuracy of microscale magnetophoresis has improved significantly over the course of several decades of development. However, most of the studies so far were using magnetic microbead composed of nanosphere particle for magnetophoretic actuation purpose. Here, we developed an in-house method for magnetic sample analysis called quadrupole magnetic steering control (QMSC). QMSC was used to study the magnetophoretic behavior of polystyrene microbeads decorated with iron oxide nanospheres-coated polystyrene microbeads (IONSs-PS) and iron oxide nanorods-coated polystyrene microbeads (IONRs-PS) under the influence of a quadrupole low field gradient. During a 4-s QMSC experiment, the IONSs-PS and IONRs-PS were navigated to perform 180° flip and 90° turn formations, and their kinematic results (2 s before and 2 s after the flip/turn) were measured and compared. The results showed that the IONRs-PS suffered from significant kinematic disproportion, translating a highly uneven amount of kinetic energy from the same magnitude of magnetic control. Combining the kinematic analysis, transmission electron microscopy micrographs, and vibrating sample magnetometry measurements, it was found that the IONRs-PS experienced higher fluid drag force and had lower consistency than the IONSs-PS due to its extensive open fractal nanorod structure on the bead surface and uneven magnetization, which was attributed to its ferrimagnetic nature.
Intellectual disability, a genetically and clinically varied disorder and is a significant health problem, particularly in less developed countries due to larger family size and high ratio of consanguineous marriages. In the current genetic study, we investigate and find the novel disease causative factors in the four Pakistani families with severe type of non-syndromic intellectual disability. For genetic analysis whole-exome sequencing (WES) and Sanger sequencing was performed. I-TASSER and Cluspro tools were used for Protein modeling and Protein–protein docking. Sanger sequencing confirms the segregation of novel homozygous variants in all the families i.e., c.245 T > C; p.Leu82Pro in SLC50A1 gene in family 1, missense variant c.1037G > A; p.Arg346His in TARS2 gene in family 2, in family 3 and 4, nonsense mutation c.234G > A; p.Trp78Term and missense mutation c.2200G > A; p.Asp734Asn in TBC1D3 and ANAPC2 gene, respectively. In silico functional studies have found the drastic effect of these mutations on protein structure and its interaction properties. Substituted amino acids were highly conserved and present on highly conserved region throughout the species. The discovery of pathogenic variants in SLC50A1, TARS2, TBC1D1 and ANAPC2 shows that the specific pathways connected with these genes may be important in cognitive impairment. The decisive role of pathogenic variants in these genes cannot be determined with certainty due to lack of functional data. However, exome sequencing and segregation analysis of all filtered variants revealed that the currently reported variants were the only variations from the respective families that segregated with the phenotype in the family.
Chronic rhinosinusitis with nasal polyps (CRSwNP) is a persistent inflammation of the sinonasal mucosa. CRSwNP treatments are associated with inconsistent efficacy and recurrence of symptoms. Dynorphin 1-17 (DYN 1-17) and its fragments have been shown to modulate the immune response in various inflammatory conditions. This study aimed to investigate the effect of different pH and degrees of inflammation on DYN 1-17 metabolism in human CRSwNP tissues. DYN 1-17 was incubated with grade 3 and grade 4 inflamed tissues of CRSwNP patients at pH 5.5 and pH 7.4 over a range of incubation periods. The resulting fragments were identified using an ultra-performance liquid chromatography (UPLC) system coupled to quadrupole-time of flight (QTOF) mass spectrometry based on their accurate mass. The rate of DYN 1-17 fragmentation was slower at pH 5.5 in comparison to pH 7.4. The extent and rate of metabolism of DYN 1-17 were much lower in grade 3 inflamed tissue (31–32 fragments) than in grade 4 (34–41 fragments). N-Terminal fragments (DYN 1-15, 1-11, 1-10, and 1-6) were metabolized slower at pH 5.5 as compared to pH 7.4. DYN 1-12, 1-8, 2-10, 4-10, 5-10, and 8-14 were only observed under the inflammatory pH while DYN 5-17 and 6-17 were only identified upon incubation with grade 4 CRSwNP tissues. DYN 1-17 metabolism was significantly affected by the pH level and the severity of the inflammation of CRSwNP tissues, indicating the potential roles of DYN 1-17 and its fragments in modulating the inflammatory response and their avenue as therapeutics in future studies.
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27,436 members
Tiem Leong Yoon
  • School of Physics
Zhari Ismail
  • Discipline of Pharmaceutical Chemistry
Mohd Rizal Arshad
  • School of Electrical and Electronic Engineering
Hasni Arsad
  • Advanced Medical and Dental Institute (AMDI)
Arman Zaharil Mat Saad
  • Reconstructive Sciences Unit
Jalan Sungai Dua, 11800, George Town, Pulau Pinang, Malaysia
Head of institution
Professor Dr. Faisal Rafiq Mahamd Adikan