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    Pengaruh Mirza Basyiruddin Mahmud Ahmad dalam tafsiran Al-Quran dan penyebaran ajaran Qadiani di Sumatera, Indonesia (Influence of Mirza Basyiruddin Mahmud Ahmad in Quranic Interpretation and Spreading of Qadiani Teaching in Sumatera, Indonesia)

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    Mirza Basyiruddin Mahmud Ahmad is the second caliph of Jemaat Ahmadiyyah Qadiani, who tried to develop his thoughts in understanding the Qur’an to the whole world including the Island of Sumatra. Basyiruddin’s thoughts have caused controversy while believing the death of Jesus and prophethood of Mirza Ghulam Ahmad. This article aims to examine the influence of these ideas in Sumatra. Regions that were the focus of the study are Aceh, West Sumatra and North Sumatra. This study used the method of library research and interviews. The results of this study found that Basyiruddin’s thoughts were opposed by public, prominent scholars and government, because of contradiction to the fundamentals of Islamic religion. Therefore, these thoughts did not have a significant effect to the whole Sumatra. © 2019, Academy of Islamic Studies, Dept of Islamic History and Civilization, University of Malaya. All rights reserved

    Application of solar quiet (Sq) current in determining mantle conductivity-depth structure in Malaysia

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    The mantle electrical conductivity-depth structure of Malaysia was determined for the first time using solar quiet day ionospheric current (Sq) variations. Spherical harmonic analysis (SHA) was employed to separate the external and internal field contribution to the Sq variations. A transfer function was applied in estimating the conductivity-depth profile for the paired of external and internal coefficients of the SHA. We observed a downward increase in electrical conductivity with initial magnitude of 0.0065 S/m at a depth of ∼ 56 km which gradually rose to 0.0106 and 0.0140 S/m at 118 and 180 km. Subsequently, the conductivity profile rose to about 0.0228 S/m at 380 km (near the base of the upper mantle) and reached 0.0260 S/m at 435 km, after which a sharp steep increase was observed at 450 km with conductivity profile of 0.0278 S/m. Consequently, the conductivity profile increases significantly to about 0.1367 S/m at a depth of 973 km and reached its peak value 0.1975 S/m at the depth of 1097 km in the lower mantle with no indication of leveling off. An evidence of discontinuity was observed near 390–460 km and 675–746 km. A slight increase in conductivity values at depth between 150 and 300 km corresponds to the region of unusual global low velocity zone with high electrical conductivity. The conductivity profile showed a less steep increase above 450 km below which a steep increase was observed. The present profile showed the deepest penetration depth which may be attributed to the influence of equatorial electrojet current (EEJ) that is actively supported by the conductive properties of the Earth's interior within the study region. © 2018 Elsevier Lt

    The Yield Prediction of Synthetic Fuel Production from Pyrolysis of Plastic Waste by Levenberg–Marquardt Approach in Feedforward Neural Networks Model

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    The conversion of plastic waste into fuel by pyrolysis has been recognized as a potential strategy for commercialization. The amount of plastic waste is basically different for each country which normally refers to non-recycled plastics data; consequently, the production target will also be different. This study attempted to build a model to predict fuel production from different non-recycled plastics data. The predictive model was developed via Levenberg-Marquardt approach in feed-forward neural networks model. The optimal number of hidden neurons was selected based on the lowest total of the mean square error. The proposed model was evaluated using the statistical analysis and graphical presentation for its accuracy and reliability. The results showed that the model was capable to predict product yields from pyrolysis of non-recycled plastics with high accuracy and the output values were strongly correlated with the values in literature. © 2019 by the authors

    Bond strength of the interface between normal concrete substrate and GUSMRC repair material overlay

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    This study investigated the interfacial bond strength between a new Green Universiti Sains Malaysia Reinforced Concrete (GUSMRC)as a repair material and the existing normal concrete substrate (NC)using two methods of surface treatment: grooving and sandblasting. The bond strength was evaluated via the slant shear, splitting tensile, and pull-off strength tests at 7, 28, and 90 days. The results showed that the bond strength of the NC/GUSMRC composite was extremely high, especially with the sandblasting surface treatment. The slant shear results showed that the specimens with sandblasting surface treatment showed almost 1.5 times higher slant shear strength than the strength of those with the grooving surface treatment at the three tested ages. The splitting strengths of the sandblasted samples were 8.3%, 20.7%, and 18.5% higher than the strengths of the grooved samples at 7, 28, and 90 days, respectively. Similarly, the pull-off strengths of the sandblasted specimens were 2.3%, 10%, and 14.5% higher at 7, 28, and 90 days, respectively. The bond strength increased as the age of the composite increased. Therefore, GUSMRC has great potential in the rehabilitation of RC structures. © 2019 Elsevier Lt

    Limits on contact interactions and leptoquarks at HERA

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    High-precision HERA data corresponding to a luminosity of around 1 fb-1 have been used in the framework of eeqq contact interactions (CI) to set limits on possible high-energy contributions beyond the Standard Model to electron-quark scattering. Measurements of the inclusive deep inelastic cross sections in neutral and charged current ep scattering were considered. The analysis of the ep data has been based on simultaneous fits of parton distribution functions including contributions of CI couplings to ep scattering. Several general CI models and scenarios with heavy leptoquarks were considered. Improvements in the description of the inclusive HERA data were obtained for a few models. Since a statistically significant deviation from the Standard Model cannot be established, limits in the TeV range were set on all models considered. © 2019 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the »https://creativecommons.org/licenses/by/4.0/» Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI

    COP negotiations and Malaysian climate change roadmap: a comparative assessment using a dynamic environmental model

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    This study critically evaluates two COP proposals on Malaysia that have been under consideration to reduce climate damage. A top-down disaggregation framework deploying an “Empirical Regional Downscaling Dynamic Integrated Model of Climate and the Economy” is used to evaluate the local government climate roadmap and Malaysia’s emissions reduction agendas under COP21 and subsequently COP22 proposals. The findings show that the costs from climate damage over the period 2010–2110 under the Malaysian Optimal Climate Action scenario will amount to MYR5,483 (US1589)billion.ThecommensurateclimatedamagecostsundertheCOP21andCOP22scenariowouldbeMYR5,264(US1589) billion. The commensurate climate damage costs under the COP21 and COP22 scenario would be MYR5, 264 (US1526) billion. Thus, the effective proposal for reducing climate damage in Malaysia over the period 2010–2110 is the COP22 time-adjusted COP21 proposal but there are a number of macroeconomic cost implications for savings and consumption that policy makers must address before acting. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature

    The influence of age-associated comorbidities on responses to combination antiretroviral therapy in older people living with HIV

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    Introduction: Multiple comorbidities among HIV-positive individuals may increase the potential for polypharmacy causing drug-to-drug interactions and older individuals with comorbidities, particularly those with cognitive impairment, may have difficulty in adhering to complex medications. However, the effects of age-associated comorbidities on the treatment outcomes of combination antiretroviral therapy (cART) are not well known. In this study, we investigated the effects of age-associated comorbidities on therapeutic outcomes of cART in HIV-positive adults in Asian countries. Methods: Patients enrolled in the TREAT Asia HIV Observational Database cohort and on cART for more than six months were analysed. Comorbidities included hypertension, diabetes, dyslipidaemia and impaired renal function. Treatment outcomes of patients ≥50 years of age with comorbidities were compared with those <50 years and those ≥50 years without comorbidities. We analysed 5411 patients with virological failure and 5621 with immunologic failure. Our failure outcomes were defined to be in-line with the World Health Organization 2016 guidelines. Cox regression analysis was used to analyse time to first virological and immunological failure. Results: The incidence of virologic failure was 7.72/100 person-years. Virological failure was less likely in patients with better adherence and higher CD4 count at cART initiation. Those acquiring HIV through intravenous drug use were more likely to have virological failure compared to those infected through heterosexual contact. On univariate analysis, patients aged <50 years without comorbidities were more likely to experience virological failure than those aged ≥50 years with comorbidities (hazard ratio 1.75, 95% confidence interval (CI) 1.31 to 2.33, p < 0.001). However, the multivariate model showed that age-related comorbidities were not significant factors for virological failure (hazard ratio 1.31, 95% CI 0.98 to 1.74, p = 0.07). There were 391 immunological failures, with an incidence of 2.75/100 person-years. On multivariate analysis, those aged <50 years without comorbidities (p = 0.025) and age <50 years with comorbidities (p = 0.001) were less likely to develop immunological failure compared to those aged ≥50 years with comorbidities. Conclusions: In our Asia regional cohort, age-associated comorbidities did not affect virologic outcomes of cART. Among those with comorbidities, patients <50 years old showed a better CD4 response. © 2019 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society

    Effect of Manganese on Co–Mn/CNT Bimetallic Catalyst Performance in Fischer–Tropsch Reaction

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    Cobalt (Co) catalyst is supported by carbon nanotubes (CNT) using a strong electrostatic adsorption (SEA) method. To promote activity and selectivity as well as find the optimum loading percentage and its effect on catalyst performance, manganese (Mn) has been added to the Co/CNT catalyst. Samples were characterized by a scanning electron microscope (SEM-EDX), transmission electron microscope (TEM), hydrogen temperature programmed reduction (H2-TPR), Zeta potential, Brunauer-Emmett-Teller (BET) analysis, X-ray diffraction (XRD), and X-ray spectroscopy (XPS). TEM images illustrated an intake of metal particles which were highly dispersed, having a narrow particle size distribution of 6-8 nm to the external and internal CNT support. H2-TPR showed a lower temperature reduction with Mn at 420 °C for Fischer-Tropsch synthesis (FTS) reaction. The Co-Mn/CNT catalyst performance test for FTS was performed at a temperature of 240 °C in a fixed-bed micro-reactor at a pressure of 2.0 MPa. The addition of manganese resulted in a lower methane selectivity and a higher C5+ product with an optimum percentage of 5% of manganese. CO conversion was 86.6% and had a C5+ selectivity of 81.5%, which was higher than the catalysts obtained using only Co on pretreated CNT. © 2019 by the authors

    Risk of concentrations of major air pollutants on the prevalence of cardiovascular and respiratory diseases in urbanized area of Kuala Lumpur, Malaysia

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    Rapid urbanisation in Malaysian cities poses risks to the health of residents. This study aims to estimate the relative risk (RR) of major air pollutants on cardiovascular and respiratory hospitalisations in Kuala Lumpur. Daily hospitalisations due to cardiovascular and respiratory diseases from 2010 to 2014 were obtained from the Hospital Canselor Tuanku Muhriz (HCTM). The trace gases, PM10 and weather variables were obtained from the Department of Environment (DOE) Malaysia in consistent with the hospitalisation data. The RR was estimated using a Generalised Additive Model (GAM) based on Poisson regression. A “lag” concept was used where the analysis was segregated into risks of immediate exposure (lag 0) until exposure after 5 days (lag 5). The results showed that the gases could pose significant risks towards cardiovascular and respiratory hospitalisations. However, the RR value of PM10 was not significant in this study. Immediate effects on cardiovascular hospitalisations were observed for NO2 and O3 but no immediate effect was found on respiratory hospitalisations. Delayed effects on cardiovascular and respiratory hospitalisations were found with SO2 and NO2. The highest RR value was observed at lag 4 for respiratory admissions with SO2 (RR = 1.123, 95% CI = 1.045–1.207), followed by NO2 at lag 5 for cardiovascular admissions (RR = 1.025, 95% CI = 1.005–1.046). For the multi-pollutant model, NO2 at lag 5 showed the highest risks towards cardiovascular hospitalisations after controlling for O3 8 h mean lag 1 (RR = 1.026, 95% CI = 1.006–1.047), while SO2 at lag 4 showed highest risks towards respiratory hospitalisations after controlling for NO2 lag 3 (RR = 1.132, 95% CI = 1.053–1.216). This study indicated that exposure to trace gases in Kuala Lumpur could lead to both immediate and delayed effects on cardiovascular and respiratory hospitalisations

    The mediating effects of product returns on the relationship between green capabilities and closed-loop supply chain adoption

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    This research explores the mediating effects of product returns on the relationship between a firm's green capabilities and its adoption of closed-loop supply chain. Green capability is characterized in terms of product recovery, supply chain integration, and environmentally friendly manufacturing. A structural equation model using survey data drawn from ISO 14001 certified manufacturers in Malaysia is used to test the research hypotheses. The results reveal that recovery and integration capabilities positively influence product returns, while manufacturing and integration capabilities and product returns influence closed loop supply chain adoption. The results also indicate that the volume, type, timing, and quality of product returns partially mediate relationships between recovery and integration capabilities and closed-loop supply chain adoption. The findings highlight the importance of taking into account the complexities of product returns as part of efforts to increase the effects of green capabilities on closed-loop supply chain adoption

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