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    The emergence of colistin-resistant Klebsiella pneumoniae strains from swine in Malaysia

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    Objective: Colistin is the last line of therapy for infections caused by multidrug-resistant Gram-negative bacteria. The objective of this study was to determine the phenotypic and genotypic characteristics of colistin-resistant Klebsiella pneumoniae (K. pneumoniae) isolated from swine samples in Malaysia. Methods: A total of 46 swine K. pneumoniae strains isolated from 2013–2015 in Malaysia were analysed for the production of extended-spectrum β-lactamases and carbapenemase. The resistance traits and genetic diversity of these strains were characterised by polymerase chain reaction, conjugation, plasmid analysis, and pulsed-field gel electrophoresis. Results: Nineteen of 46 strains were multidrug resistant while 13 were resistant to colistin. The majority of colistin-resistant strains harboured blaTEM gene (92.3%), followed by blaSHV (69.23%), blaCTXM-1 (38.46%), and blaMCR-1 (23.08%). All three colistin-resistant strains had transferable plasmids and the colistin resistance gene blaMCR-1. Genotyping by pulsed-field gel electrophoresis showed high genetic diversity among the K. pneumoniae and that the colistin-resistant K. pneumoniae strains were heterogenous. Conclusion: It is believed that this is the first report of colistin-resistant K. pneumoniae among swine strains associated with mcr-1 plasmid in Malaysia. Due to the emergence of β-lactam, carbapenem and colistin resistance, the use of colistin in animal husbandry and agriculture should be avoided to prevent treatment failure. © 2019 International Society for Chemotherapy of Infection and Cance

    Analysis of dental services distribution in Malaysia: a geographic information systems – based approach

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    Objective: The aim of this study was to analyse, in detail, the distribution of primary dental clinics in relation to the Malaysian population and relative population wealth, to test the hypothesis that an uneven distribution of dental services exists in Malaysia. Method: This 2016 study located every dental practice in Malaysia (private and public) and mapped these practices against population, using Geographic Information Systems (GIS) tools. Population clusters within 5, 10 and 20 km of a dental clinic were identified, and clinic-to-population ratios were ascertained. Population data were obtained from the Population and Housing Census of Malaysia 2010. Population relative wealth was obtained from the 2014 Report on Household Income and Basic Amenities Survey for Malaysia. The physical address for each dental practice in Malaysia was gathered from the Official Portal of Ministry of Health Malaysia. All data for analysis were extracted from the integrated database in Quantum GIS (QGIS) into Microsoft Excel. Result: The population of Malaysia (24.9 million) was distributed across 127 districts, with 119 (94%) having at least one dental clinic. Sixty-four districts had fewer than 10 dental clinics, and 11.3% of Malaysians did not reside in the catchment of 20 km from any dental clinic. The total dental clinic-to-population ratio was 1:9,000: for public dental clinics it was 1:38,000 and for private clinics it was 1:13,000. Conclusion: Dental services were distributed relative to high population density, were unevenly distributed across Malaysia and the majority of people with the highest inaccessibility to a dental service resided in Malaysian Borneo. © 2018 FDI World Dental Federatio

    A Kernel Bayesian Adaptive Resonance Theory with A Topological Structure

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    This paper attempts to solve the typical problems of self-organizing growing network models, i.e. (a) an influence of the order of input data on the self-organizing ability, (b) an instability to high-dimensional data and an excessive sensitivity to noise, and (c) an expensive computational cost by integrating Kernel Bayes Rule (KBR) and Correntropy-Induced Metric (CIM) into Adaptive Resonance Theory (ART) framework. KBR performs a covariance-free Bayesian computation which is able to maintain a fast and stable computation. CIM is a generalized similarity measurement which can maintain a high-noise reduction ability even in a high-dimensional space. In addition, a Growing Neural Gas (GNG)-based topology construction process is integrated into the ART framework to enhance its self-organizing ability. The simulation experiments with synthetic and real-world datasets show that the proposed model has an outstanding stable self-organizing ability for various test environments. © 2019 World Scientific Publishing Company

    Optimization of conditions for improved solar energy harvesting application by hydrothermally grown TiO2 nanorods

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    In this study, using the optimum annealing temperature and time for hydrothermally grown TiO 2 nanorods, photooxidation of water at different pH values of the electrolyte solution is investigated. The composition, crystallinity and topographic studies of films, sintered at different temperatures of 200–500 °C for 2 h and annealed for 1–4 h at 400 °C, were evaluated by X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and field emission scanning electron microscopy. The sintering at high temperature and for longer time demonstrates an increase in crystallinity, but at the same time agglomeration of nanorods for prolonged heating and at high temperature leads to cracking at the surface of the films. Further, UV–Vis spectroscopic studies revealed prolonged heating and high-temperature sintering resulted in a red shift in light absorption edge of the films. The chronoamperometric measurement results under regular interrupted chopping revealed that the sample annealed at 400 °C for 2 h gives the best photoelectrochemical response with photocurrent density of 522 µA cm − 2 using 0.5M NaOH. The chronoamperometric response under different pH values of 13.7, 7.2 and 2.5 proved that TiO 2 gives the best response under a basic pH of 13.7 and the least under acidic media. The electrochemical impedance studies provided an insight into the charge transfer mechanism under dark and illumination with R ct value of 1188.8 Ω under dark and 164.5 Ω under light conditions for the film annealed at 400 °C for 2 h. [Figure not available: see fulltext.]. © 2019, Iranian Chemical Society

    Economic Burden of ESRD to the Malaysian Health Care System

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    Introduction: Prevalence of chronic kidney disease (CKD) in Malaysia is 9.07% of the total population, of which 0.36% are at stage 5 CKD or end-stage renal disease (ESRD). Public-private partnership has improved accessibility of renal replacement therapies (RRT), especially dialysis, in Malaysia, but the economic burden of the existing RRT financing mechanism, which is predominantly provided by the public sector, has never been quantified. Methods: Primary data were collected through a standardized survey, and secondary data analysis was used to derive estimates of the ESRD expenditure. Results: Total annual expenditure of ESRD by the public sector has grown 94% within a span of 7 years, from Malaysian Ringgit [MYR] 572 million (US dollars [USD] 405 million, purchasing power parity [PPP] 2010) in 2010 to MYR 1.12 billion (USD 785 million, PPP 2016) in 2016. The total ESRD expenditure in 2010 constituted 2.95% of the public sector's total health expenditure, whereas in 2016, the proportion has increased to 4.2%. Only 6% of ESRD expenditure was spent on renal transplantation, and the remaining 94% was spent on dialysis. Conclusion: The share of ESRD expenditure in total health expenditure for the public sector is considered substantial given only a small proportion of the population is affected by the disease. The rapid increase in expenditure relative to the national total health expenditure should warrant the relevant authorities about sustainability of the existing financing mechanism of ESRD and the importance to institutionalize more drastic preventive measures. © 2019 International Society of Nephrolog

    The execution of the green building project in klang valley, Malaysia: A pilot study

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    Execution of the green building project specifically among the housing developers in Malaysia is still at its infancy. As of August 2016, there are only 16 housing projects certified by the Green Building Index (GBI) under the category of Residential New Construction (RNC) since the assessment systems established in 2010. The authors address this issue in the context of the factors affecting the execution of the green building project among the housing developers in Klang Valley. A pilot study by using questionnaire survey was conducted among 30 housing developers from 10 different zones divided by the Ministry of Housing and Local Government, Malaysia. This paper aimed to report the results of the reliability test of the designed questionnaire. The results based on the Cronbach’s Alpha analysis showed that the items used in the questionnaire were reliable and obtained an acceptable level of internal consistency, which were relevant for the main study. The pilot study revealed that only 9 out of 30 respondents had the completed or ongoing green building projects. The findings exposed the level of knowledge, emotion, value, attitude, behavior and the potential factors affecting the execution of the green building projects among the housing developers in Klang Valley. © Universiti Putra Malaysia Press

    Dynamics and binding interactions of peptide inhibitors of dengue virus entry

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    In this study, we investigate the binding interactions of two synthetic antiviral peptides (DET2 and DET4) on type II dengue virus (DENV2) envelope protein domain III. These two antiviral peptides are designed based on the domain III of the DENV2 envelope protein, which has shown significant inhibition activity in previous studies and can be potentially modified further to be active against all dengue strains. Molecular docking was performed using AutoDock Vina and the best-ranked peptide-domain III complex was further explored using molecular dynamics simulations. Molecular mechanics-Poisson–Boltzmann surface area (MM-PBSA) was used to calculate the relative binding free energies and to locate the key residues of peptide–protein interactions. The predicted binding affinity correlated well with the previous experimental studies. DET4 outperformed DET2 and is oriented within the binding site through favorable vdW and electrostatic interactions. Pairwise residue decomposition analysis has revealed several key residues that contribute to the binding of these peptides. Residues in DET2 interact relatively lesser with the domain III compared to DET4. Dynamic cross-correlation analysis showed that both the DET2 and DET4 trigger different dynamic patterns on the domain III. Correlated motions were seen between the residue pairs of DET4 and the binding site while binding of DET2 results in anti-correlated motion on the binding site. This work showcases the use of computational study in elucidating and explaining the experiment observation on an atomic level. © 2019, Springer Nature B.V

    The New Malay Woman’s jiwa as a Postcolonial Structure of Feeling

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    Women from newly liberated postcolonial societies have produced fiction and non-fiction work with a critical view on women’s inferior status and discriminatory cultural practices that powerfully resonate with contemporary feminist opinions. However, their views are parallel insofar as an understanding of ‘women’ remains unproblematised. In this article, ‘women’ and ‘feminism’ are unpacked from a domestic cosmopolitan lens, particularly from the perspective of the postcolonial woman’s spirit of openness to the other. The postcolonial subject in question is the New Malay Woman, a cultural construction in the early years of Malaysia’s independence, a female figure formed through her critique of modernity and encounters with transnationalism. But it is through the New Malay Woman’s soul or jiwa, explicated in the essays and semi-autobiographical fiction of Malay women writers in the 1960s, that we find ‘structures of feeling’ overcoming facile parallels and temporal distances between the early postcolonial woman and contemporary feminist wherever she might be. It is hoped that from explicating the ‘structures of feeling’ that the meaning of ‘women’ and ‘emancipation’ as articulated by early postcolonial women writers is better understood. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group

    Characterization of MOSkin detector for in vivo dose verification during Cobalt-60 high dose-rate intracavitary brachytherapy

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    In vivo dosimetry in high dose-rate (HDR) intracavitary brachytherapy (ICBT) is important for assessing the true dose received by surrounding organs at risk during treatment. It also serves as part of the treatment delivery quality assurance and verification program with the use of a suitable dosimeter. Such a dosimeter should be characterized under brachytherapy conditions before clinical application to ensure the accuracy of in vivo measurement. In this study, a MOSFET-based detector, MOSkin, was calibrated and characterized under HDR Cobalt-60 (Co-60) brachytherapy source. MOSkin possessed the major advantages of having small physical and dosimetric sizes of 4.8 × 10 −6 mm 3 with the ability to provide real-time measurements. Using solid water and polymethyl methacrylate (PMMA) phantom, the detectors’ reproducibility, linearity, angular and distance dependency was tested for its suitability as an in vivo detector. Correction factors to account for differences in depth measurements were determined. The MOSkin detector showed a reliable response when tested under Co-60 brachytherapy range of doses with an excellent linearity of R 2 = 0.9997 and acceptable reproducibility. A phantom verification study was also conducted to verify the differences between MOSkin responses and treatment planning (TPS) calculated doses. By taking into account several correction factors, deviations ranging between 0.01 and 0.4 Gy were found between MOSkin measured and TPS doses at measurement distance of 20–55 mm. The use of MOSkin as the dosimeter of choice for in vivo dosimetry under Co-60 brachytherapy condition is feasible. © 2019 Associazione Italiana di Fisica Medic

    Secure and Energy-Efficient Data Aggregation Method Based on an Access Control Model

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    Wireless sensor networks (WSNs) consist of a large number of sensor nodes that are distributed to capture the information about an area of interest. In WSN, many of the secure data aggregation works are conducted without addressing the authentication process. It is challenging to implement authentication while preserving the energy consumption in the network. The previous research that focus on these issues have several limitations, such as sharing the security key and the key length with a base station node, and not much attention is given to enhance the authentication of the Medium Access Control (MAC) server. This makes the data aggregation network are exposed to malicious activities. This paper presents a new protocol to address the security and energy issue in Wireless Sensor Network (WSN). This newly developed protocol is named Secure and Energy-Efficient Data Aggregation (SEEDA), which is the extension of SDAACA protocol. The proposed protocol aims to enhance authentication by generating a random value and random timestamp with a secret key. The base station node will verify the fake aggregated data when the packets are received using the generated key earlier. Furthermore, the attacks are detected and prevented by utilizing secure node authentication, data fragmentation algorithms, fully homomorphic encryption, and access control model. The secure node authentication algorithm prevents attacks from accessing the network. To avoid network delays, the base station node utilizes the distance information between the participating nodes. To ensure the reliability of our proposed method, we simulate two well-known attacks, called Sybil and sinkhole attacks. Several experimental scenarios are conducted to observe their effect. Evaluation metrics such as malicious activity detection rate, energy consumption, end-to-end delay, and resilience time are measured. The performance of the proposed protocol is compared with SDA, SDAT, SDALFA, EESSDA, SDAACA, and EESDA, which is a widely used protocol in the area of secure data aggregation. The simulation results show that the proposed SEEDA method outperforms the existing scheme with 98.84% malicious nodes detection rate, 3.04 joules for energy consumption, the maximum delay of 0.038 seconds, and the resilient time 0.054, 0.075 seconds when 8%,16% of malicious nodes affecting the network. © 2013 IEEE

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