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    19316 research outputs found

    Heavy metals (Cr, Pb, Cd, Ni) in aerosols emitted from electronic cigarettes sold in Malaysia

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    While past studies have detected heavy metals in aerosols emitted from electronic cigarettes (ECIG), they have provided little information detailing the practical implications of the findings to the Malaysian population due to variations between products. The aims of this study were to analyse heavy metals of interest (HMOI) in the aerosols emitted from selected ECIG and to evaluate potential health risks by referring to the permissible daily exposure (PDE) from inhalational medications defined by the United States Pharmacopeia Chapter 232. All four HMOI were detected in aerosols emitted from the selected ECIG in Sarawak. Among the four, Cr was present at the highest median levels (6.86 ng/m3), followed by Ni (0.30 ng/m3), Pb (0.19 ng/m3) and Cd (0.01 ng/m3). Five out of 100 combinations (5%) of ECIG and ECIG liquids were found to emit Cr that exceed the recommended PDE. Future studies examining more heavy metal variants, using a larger sample size and different analytical techniques to compare various ECIGs are recommended. © 2019, © 2019 Taylor & Francis Group, LLC

    Bundled plastic optical fiber based sensor for ECG signal detection

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    This study demonstrates the development of a novel low-cost bundled plastic optical fiber (POF) displacement sensor for the measurement of amplitude and frequency of heart rate signal. A compact optical setup is developed in the laboratory for use in the testing. It consists of a fiber optic transmitter, fiber optic bundled probe and photodiode detector, and an electrocardiogram (ECG) simulator as a heart rate signal. The sensitivity of the sensor is found to be 4.6 mV/mm, and thus it is capable of measuring heart rate from 30 bpm to 300 bpm (for the amplitude of ECG at 0.5, 1.0 and 2.0 mV) with linearity of more than 99 %.The results demonstrate that the proposed fiber optic based heart rate sensor is not only easy-to-make, cost-effective and robust but also offers sensitive, stable and high precision heart beat measurements. © 2019 Elsevier Gmb

    Financial Literacy and Retirement Planning among Government Officers in Malaysia

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    This study examines the level of financial literacy, financial behaviour and retirement planning behaviour and its dynamics among Malaysian government officers involving 320 employees working in the federal government administrative centre in Putrajaya and Kuala Lumpur using a questionnaire. Findings show high level of financial literacy, good financial behaviour but a mediocre in retirement planning behaviour, and only education and personal income positively influence financial literacy. Age and gender of officers do not influence financial literacy. Furthermore, financial literacy does not correlate with retirement planning and neither does it mediate the relationship between financial behaviour and retirement planning. © 2019, © 2019 Taylor & Francis Group, LLC

    United in Fight against prOstate cancer (UFO) registry: first results from a large, multi-centre, prospective, longitudinal cohort study of advanced prostate cancer in Asia

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    Objectives: To document the management of advanced prostate cancer including diagnosis, prognosis, treatment, and care, in real-world practice in Asia using the United in Fight against prOstate cancer (UFO) registry. Patients and Methods: We established a multi-national, longitudinal, observational registry of patients with prostate cancer presenting to participating tertiary care hospitals in eight Asian countries. A total of 3636 eligible patients with existing or newly diagnosed high-risk localised prostate cancer (HRL), non-metastatic biochemically recurrent prostate cancer (M0), or metastatic prostate cancer (M1), were consecutively enrolled and are being followed-up for 5 years. Patient history, demographic and disease characteristics, treatment and treatment decisions, were collected at first prostate cancer diagnosis and at enrolment. Patient-reported quality of life was prospectively assessed using the European Quality of Life-five Dimensions, five Levels (EQ-5D-5L) and Functional Assessment of Cancer Therapy for Prostate Cancer questionnaires. In the present study, we report the first interim analysis of 2063 patients enrolled from study start (15 September 2015) until 18 May 2017. Results: Of the 2063 enrolled patients, 357 (17%), 378 (19%), and 1328 (64%) had HRL, M0 or M1 prostate cancer, respectively. The mean age at first diagnosis was similar in each group, 56% of all patients had extracapsular extension of their tumour, 28% had regional lymph node metastasis, and 53% had distant metastases. At enrolment, 62% of patients had at least one co-morbidity (mainly cardiovascular disease or diabetes), 91.8% of M1 patients had an Eastern Cooperative Oncology Group performance score of <2 and the mean EQ-5D-5L visual analogue score was 74.6–79.6 across cohorts. Treatment of M1 patients was primarily with combined androgen blockade (58%) or androgen-deprivation therapy (either orchidectomy or luteinising hormone-releasing hormone analogues) (32%). Decisions to start therapy were mainly driven by treatment guidelines and disease progression. Decision to discontinue therapy was most often due to disease progression (hormonal drug therapy) or completion of therapy (chemotherapy). Conclusion: In the UFO registry of advanced prostate cancer in Asia, regional differences exist in prostate cancer treatment patterns that will be explored more deeply during the follow-up period; prospective follow-up is ongoing. The UFO registry will provide valuable descriptive data on current disease characteristics and treatment landscape amongst patients with prostate cancer in Asia. © 2019 The Authors BJU International Published by John Wiley & Sons Ltd on behalf of BJU Internationa

    A LabVIEW module to promote undergraduate research in control of AC servo motors of robotics manipulator

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    This paper presents a project-based learning pedagogy for undergraduate mechanical engineering students which integrates traditional hardware-based laboratory with LabVIEW to control the angular position, velocity, and acceleration of AC servo motors of a six-degree of freedom manipulator. The proposed experimental modules have been proved to be very effective in assisting teams of undergraduate students within the Department of Mechanical, Materials and Manufacturing Engineering at the University of Nottingham, Malaysia Campus, who have used the modules in designing a new mechanical structure of a robot during their capstone design project. The proposed pedagogy inspired undergraduate students to publish their first paper based on the outcomes of their project. The focus on this paper is to present how the students' learning experience has been significantly enforced and their role in developing the modules introduced in this paper. Three modules are presented; the first configures a timer to generate a signal that drives the servo motors. The second drives the servo motor to a specific angular position with a constant angular velocity. Finally, the third is used to control the servo motor to follow any desired angular position, velocity, and acceleration. © 2019 Wiley Periodicals, Inc

    Lightweight authentication technique for secure communication of edge/fog data-centers

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    Edge computing has significantly enhanced the capabilities of cloud computing. Edge data-centres are used for storing data of the end-user devices. Secure communication between the legitimate edge data-centres during the load balancing process has attracted industrial and academic researchers. Recently, Puthal et al. have proposed a technique for authenticating edge datacenters to enable secure load balancing. However, the resource-constraint nature of the edge data-centres is ignored. The scheme is characterized by complex computation and memory intensive cryptographic protocol. It is also vulnerable to key escrow attack because the secret key used for encrypting and decrypting of the communicated messages is been created by the trusted cloud datacenter. Additionally, the key sharing phase of their algorithm is complex. Therefore, to address the highlighted challenges, this paper proposed a lightweight key escrow-less authentication algorithm that will ensure secure communication of resource-constrained edge data-centres during the load balancing process. The security capability of the proposed scheme has been formally evaluated using the automatic cryptographic analytical tool ProVerif. The relatively low computation and communication costs of the proposed scheme compared to the benchmark schemes proved that it is lightweight, thus suitable for resource-constrained edge datacenters. © 2020 SERSC

    Temperature and doping effects on the transport properties of SrIn2P2 Zintl compound

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    In this paper, we present and discuss temperature and doping effects on the electrical and thermal transport properties of SrIn2P2 Zintl phase along the [100] and [001] crystallographic directions. The calculations were performed by using the full-potential linearized augmented plane wave method in conjunction with Boltzmann's transport theory and Bardeen-Shockley's deformation potential with the carrier relaxation time and effective mass approximations. We calculated the band effective masses inside two energy windows of 125 meV; one above the fundamental conduction band minimum (FCBM) and the second below the valence band maximum (VBM). The calculated band effective masses exhibit a noticeable anisotropy and demonstrate that the n-type SrIn2P2 transport properties are better than those of the p-type one over the considered charge-carrier concentration range at room-, intermediate- and high-temperature, due to the proximity of the secondary conduction band minimums to the FCBM (∼58 meV). The n-type SrIn2P2 has a considerable Seebeck coefficient (429 μV/K), an extremely low electrical resistivity (0.90 mΩcm), and a relatively small lattice thermal conductivity (1.12 Wm−1K−1), which yield a figure of merit ZT of 0.87 for an electron concentration of 3.0 × 1019 cm−3 at 900 K. These results make SrIn2P2 a hopeful n-type thermoelectric material if we can further reduce its lattice thermal conductivity. © 2019 Elsevier B.V

    A question answering system in hadith using linguistic knowledge

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    Question answering system aims at retrieving precise information from a large collection of documents. This work presents a question answering method to apply on Hadith in order to provide an informative answer corresponding to the user's query. Hadith englobes stories and qualification of the prophet Muhammad (PBSL). It also includes the sayings of his companions and their disciples. The problem with current methods is that they fail to capture the meaning when comparing a sentence and a user's query; hence there is often a conflict between the extracted sentences and user's requirements. However, our proposed method has successfully tackled this problem through: (1) avoiding extract a passage whose similarity with the query is high but whose meaning is different. (2) Computing the semantic and syntactic similarity of the sentence-to-sentence and sentence-to-query. (3) Expanding the words in both the query and sentences to tackle the fundamental problem of term mismatch between sentences and the user's query. Furthermore, in order to reduce redundant Hadith texts, the proposed method uses the greedy algorithm to impose diversity penalty on the sentences. The experimental results display that the proposed method is able to improve performance compared with the existing methods on Hadith datasets. © 2019 Elsevier Lt

    Clustering and Tracking the Stability of Biological CVD Risk Factors in Adolescents: The Malaysian Health and Adolescents Longitudinal Research Team Study (MyHeARTs)

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    Background: Cardiovascular disease (CVD) risk factors tend to cluster and progress from adolescence to young adulthood. Reliable and meaningful clustering of CVD risk factors is essential to circumvent loss of information. Tracking adverse and high-risk profiles of adolescents is hoped to curb CVD progression later in life. The study aims to investigate the clustering of biological CVD risk factor among adolescents in Malaysia and the transitions between clusters over time. Method: The Malaysian Health and Adolescents Longitudinal Research Team study (MyHeARTs) examined school students aged 13 in 2012 and re-examined them in 2014 and 2016. In a two-stage stratified cluster sampling, 1,361 students were recruited, of which, 1,320 had complete data. In the follow-up, there were 881 and 637 students in 2014 and in 2016, respectively. Pearson's correlation coefficients were used to identify and remove highly correlated CVD risk factors. All risk factors were standardized into z-scores. The hierarchical and non-hierarchical (k-means) cluster analyses were used to classify students into high, medium and low risk clusters in each screening year. The tracking and stability of cluster transitions through cross-classification were enumerated with Pearson's inter-age correlations and percentages. Results: Three significant clusters of high, medium and low risk groups were derived from the clustering of eight biological CVD risk factors. The transitions between risk clusters from one screening year to the other were categorized as either stagnant, improved or adverse. The number of students who had adverse transitions increased from 15.5% (13–15 year) to 19.5% (15–17 year), 13.8 to 18.2% among the girls and 19.9 to 22.8% among the boys. For girls, the number of them who remained at high risk over the two transition periods were about the same (13.6 vs. 13.8%) whereas for boys, the percentage reduced from 14.6 to 12.3%. Conclusion: Over time, more than 12% of adolescents remained in the high risk cluster. There were sizable adverse transitions over time as more adolescents appear to be shifting toward an increased risk of having CVD. Collaborative and constant measures should be taken by parents, school, health promotion boards and policy makers to curb the multiplicative effect of clustering CVD risk factors among adolescents. © Copyright © 2020 Thangiah, Chinna, Su, Jalaludin, Al-Sadat and Majid

    Actinide and non-actinide production from UO2 fuel in W-SMR: Effects of gadolinium burnable absorber

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    Burnable neutron absorbers are used for efficient reactivity control especially in light and heavy water reactors. Effect of gadolinium burnable absorber (GdBA) on reactivity, actinide and non-actinide content of nuclear waste was investigated. Westinghouse small modular reactor (W-SMR) was studied using MCNPX 2.7 code integrated with CINDER90 for the calculations. Positive reactivity swing was observed in fuel assemblies with GdBA rods. The concentration of actinides was relatively higher in FA without GdBA rod compared to those with GdBA rods. The net activity of 241Pu and 239Np were respectively higher compared to other isotopes of plutonium and neptunium and slightly larger in FAs with GdBA rods. However, a significant increase on the concentration of non-actinide inventory was observed which increased with the number of GdBA rods. Therefore, the use of GdBA for reactivity control should be limited to avoid unrealistic reactivity swing and increased non-actinides content of the spent fuel. © 2019 Elsevier Lt

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