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    Quantum coherence and entanglement partitions for two driven quantum dots inside a coherent micro cavity

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    We explore the coherence and entanglement of two separated quantum dots placed in an open microcavity. The generated entanglement and coherence depend crucially on the two-exciton decay and the initial coherence intensity. The phenomena of sudden death and sudden birth entanglement are observed. © 2019 Elsevier B.V

    Molecular Characterization of Multidrug-Resistant and Extended-Spectrum Beta-Lactamase-Producing Klebsiella pneumoniae Isolated from Swine Farms in Malaysia

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    Aims: The high prevalence of multidrug resistance (MDR) and extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae associated with nosocomial infections has caused serious therapeutic challenges. The objectives of this study were to determine the genotypic and phenotypic characteristics of K. pneumoniae strains isolated from Malaysian swine farms and the transferability of ESBL genes by plasmids. Results: A total of 50 K. pneumoniae strains were isolated from 389 samples, which were collected from healthy and unhealthy pigs (swine rectum and oral cavities), healthy farmers (human rectum, urine, and nasal cavities), farm's environment, and animal feeds from seven Malaysian swine farms. Antimicrobial susceptibility analysis of these 50 K. pneumoniae strains showed that the majority (86%) were resistant to tetracycline, while 44% and 36% of these strains were MDR and ESBL producers, respectively. PCR and DNA sequencing of the amplicons showed the occurrence of blaTEM (15/18), blaSHV (15/18), blaCTX-M-1 group (7/18), and blaCTX-M-2 group (2/18), while only class 1 integron-encoded integrase was detected. Conjugation experiments and plasmid analysis indicated that the majority of the ESBL genes were plasmid encoded and the plasmids in 11 strains were conjugative. Genotyping by pulsed-field gel electrophoresis and repetitive extragenic palindrome-polymerase chain reaction (REP-PCR) showed that these 50 strains were genetically diverse with 44 pulsotypes and 43 REP-PCR subtypes. Conclusions: ESBL-producing K. pneumoniae strains showed high resistance to tetracycline as this antibiotic is used for prophylaxis and therapeutic purposes at the swine farms. The findings in this study have drawn attention to the issue of increasing MDR in animal husbandry and it should be taken seriously to prevent the spread and treatment failure due to antimicrobial resistance. © Copyright 2019, Mary Ann Liebert, Inc., publishers 2019

    Comparative study of the circumferential and volumetric analysis between conventional casting and three-dimensional scanning methods for transtibial socket: A preliminary study

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    Transtibial prosthetic sockets can be fabricated either by the conventional way, which involve using plaster of Paris bandages for casting. This will include modifications through hand, scanning and digital imaging of software. The aim of this study is to determine the circumferential profiles and conduct a volumetric analysis of a conventional socket that has fabrication using biosculptor technology. In doing this, a male transtibial amputee, age 28 years old with stable health condition was studied, where circumferential measurements were taken at intervals of 1 cm from the distal end of the residual limb to the medial tibial plateau level. Furthermore, the interior volume of both sockets and residuum were determined directly using water displacement method. A comparative value for the calculation of volume was also carried out using engineering mathematical equations. From these measurements, a total surface bearing transtibial sockets was fabricated to compare the changes of circumferential values of both sockets. The finding shows a percentage of the difference between the volume of the residual limb and conventional sockets to be 6.09%, whereas the biosculptor fabrication socket was 7.84% using the water displacement method. A comparison of circumferential profiles and volumetric analysis findings on the contrary showed that socket fabricated using the biosculptor technology is interchangeable with the conventional socket with more advantages, where biosculptor technology produces cheaper sockets and faster process with digital function in the procedure, unlike the conventional manual technique. © IMechE 2018

    Ethnic differences in the prevalence, socioeconomic and health related risk factors of knee pain and osteoarthritis symptoms in older Malaysians

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    Knee pain is often underreported, underestimated and undertreated. This study was conducted to estimate the prevalence, burden and further identify socioeconomic factors influencing ethnic differences in knee pain and symptoms of OA among older adults aged 55 years and over in Greater Kuala Lumpur (the capital city of Malaysia). The sample for the Malaysian Elders Longitudinal Research (MELoR) was selected using stratified random sampling, by age and ethnicity from the electoral rolls of three parliamentary constituencies. Information on knee pain was available in 1226 participants, mean age (SD) 68.96 (1.57) years (409 Malay, 416 Chinese, 401 Indian). The crude and weighted prevalence of knee pain and self-reported knee OA symptoms were 33.3% and 30.8% respectively. There were significant ethnic differences in knee pain (crude prevalence: Malays 44.6%, Chinese 23.5% and Indians 31.9%, p<0.001). The presence of two or more non-communicable diseases (NCD) attenuated the increased risk of knee pain among the ethnic Indians compared to the ethnic Chinese. The prevalence of knee pain remained significantly higher among the ethnic Malays after adjustment for confounders. While the prevalence of knee pain in our older population appears similar to that reported in other published studies in Asia, the higher prevalence among the ethnic Malays has not previously been reported. Further research to determine potential genetic susceptibility to knee pain among the ethnic Malays is recommended. © 2019 Mat et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

    Yield and quality of amaranth and water spinach as affected by organic fertilizers and legume residues

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    Amaranth (Amaranthus paniculatus) and water spinach (Ipomoea reptans) grown after legume residues with organic fertilizers are helpful to improve their yield and quality. Therefore, a study was carried out at the net house of the University of Malaya, Malaysia in pot assay from November 2014 to June 2015. Amaranth and water spinach were grown after yard long bean (YLB), bush bean (BB) and winged bean (WB) with VC+YLB, COM+YLB and FP+YLB; VC+BB, COM+BB and FP+BB; VC+WB, COM+WB and FP+WB treatments whereas legume was grown with VC, COM and FP treatments in complete randomized design. The highest biomass yield (889.81 g/m 2 ) and leaf number (15.67) of amaranth was observed in VC+YLB treatment. Maximum protein content (2.16 g/100g) was observed when amaranth was grown with VC+BB. Fe, Ca and Mg content of amaranth was also higher in VC+YLB treatment. Amaranth after YLB grown with VC showed superior performance among the treatments. For water spinach, the highest biomass yield (674.69g/m 2 ) and maximum leaf number (34.67) was observed in VC+WB treatment. Protein content of water spinach was highest (1.92 g/100g) in VC+WB treatment. Fe, Ca and Mg content in water spinach was also higher in VC+WB treatment for water spinach grown after winged bean. The biomass of bean showed a positive linear relationship with the growth and yield of amaranth and water spinach in all the treatments and rotations. The study has shown that the use of vermincompost with legume crop rotations has the potential to significantly increase yield in amaranth and water spinach. © 2019, Pakistan Agricultural Scientists Forum. All rights reserved

    Population pharmacokinetic meta-analysis of individual data to design the first randomized efficacy trial of vancomycin in neonates and young infants

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    OBJECTIVES: In the absence of consensus, the present meta-analysis was performed to determine an optimal dosing regimen of vancomycin for neonates. METHODS: A 'meta-model' with 4894 concentrations from 1631 neonates was built using NONMEM, and Monte Carlo simulations were performed to design an optimal intermittent infusion, aiming to reach a target AUC0-24 of 400 mg·h/L at steady-state in at least 80% of neonates. RESULTS: A two-compartment model best fitted the data. Current weight, postmenstrual age (PMA) and serum creatinine were the significant covariates for CL. After model validation, simulations showed that a loading dose (25 mg/kg) and a maintenance dose (15 mg/kg q12h if 89% of the treated patients. CONCLUSIONS: The results of a population meta-analysis of vancomycin data have been used to develop a new dosing regimen for neonatal use and to assist in the design of the model-based, multinational European trial, NeoVanc. © The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: [email protected]

    The practice of professional learning community in trust schools, transformation schools and high performing schools in Selangor Malaysia

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    This study aims to identify the level of Professional Learning Community (PLC) in 3 different types of school namely in Selangor. A total of 450 Malay language teachers from 42 schools in Selangor were involved as respondents in this study. This quantitative study uses survey methods for the purpose of data collection. Data were collected through a set of questionnaires which was developed through Fuzzy Delphi method based on the consensus of 12 experts. The quantitative data collected were analyzed using SPSS version 23.0 and SEM PLS 3.0. This study conveys the level of PLC practice of Malay language teachers in Selangor and the outcome is high for each PLC dimension through overall average score (Min = 3.92, SP = 0.509). In addition, the findings also show that there is a substantial relationship across dimensions of PLC. Finally, it is hoped that the findings of this study will have a positive impact on the implementation of PLC in Malaysian schools as well as for the improvement of student learning outcome. © 2019 SERSC

    Neuronal transcriptomic responses to Japanese encephalitis virus infection with a special focus on chemokine CXCL11 and pattern recognition receptors RIG-1 and MDA5

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    Japanese encephalitis virus (JEV) causes central nervous system neuronal injury and inflammation. A clear understanding of neuronal responses to JEV infection remains elusive. Using the Affymetrix array to investigate the transcriptome of infected SK-N-MC cells, 1316 and 2737 dysregulated genes (≥ 2/−2 fold change, P < 0.05) were found at 48 hours post-infection (hpi) and 60 hpi, respectively. The genes were mainly involved in anti-microbial responses, cell signalling, cellular function and maintenance, and cell death and survival. Among the most highly upregulated genes (≥ 10 folds, P < 0.05) were chemokines CCL5, CXCL11, IL8 and CXCL10. The upregulation and expression of CXCL11 were confirmed by qRT-PCR and immunofluorescence. Pathogen recognition receptors retinoic acid-inducible gene-1 (RIG-1) and melanoma differentiation-associated protein 5 (MDA5) were also upregulated. Our results strongly suggest that neuronal cells play a significant role in immunity against JEV. CXCL11, RIG-1 and MDA5 and other cytokines may be important in neuropathogenesis

    Optimisation and biological activities of bioceramic robocast scaffolds provided with an oxygen-releasing coating for bone tissue engineering applications

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    Hypoxia is one of the major challenges after scaffold implantation which can lead to cell necrosis and bacterial infection. Using of supplemental oxygen can increase the cell proliferation, encourage the cell differentiation and prevent the infections. Developing an engineered scaffold with a sustained oxygen release is an outstanding way for addressing the challenges of oxygen deficiency. In this study, the bioceramic scaffolds were fabricated from biphasic calcium phosphate (BCP) powder with the composition of 60% hydroxyapatite (HA) and 40% beta-tricalcium phosphate (β-TCP). The Robocasting technique was utilised for producing a porous structure comprising interpenetrated ceramic rods in a 3-dimensional tetragonal mesh. The scaffold was modelled by the finite element method (FEM) for computing the stress fields and predicting their mechanical performance. Calcium peroxide (CPO), as an oxygen-producing and antimicrobial biomaterial, was mixed with a polycaprolactone (PCL) solution and was coated on the scaffolds by the dip-coating method. The coating layer possessed three different percentages of CPO (1, 3 and 5 wt%). The oxygen-releasing profile proved that this design of coating-scaffold could be effective as a system of oxygen delivery. According to the antibacterial investigations, releasing of CPO from the scaffolds could inhibit the growth of E. coli and S. aureus. SBF tests confirmed that the coated scaffolds because of CPO particles on their surface presented superior apatite precipitation in comparison with the uncoated one. The differentiated osteoblastic function was monitored by measuring the alkaline phosphatase (ALP) activity. The coated BCP scaffolds with 3% and 5% CPO exhibited higher ALP activity compared to the other samples. The results demonstrated that the proposed bioceramic-based scaffolds containing oxygen-generating coating could be optimised to supply an antibacterial performance, ideal mechanical properties, improved ALP activity and higher apatite formation ability. Therefore, these scaffolds can be a promising candidate for applying in bone tissue engineering

    Integrative biomarkers of biologic aging in HIV

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