19672 research outputs found
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Determinants of credit card misuse among Gen Y consumers in urban Malaysia
No full textPurpose: The concept of “buy now pay later” leads Malaysian Generation Y (Gen Y) to excessively use their credit cards for spending. To gauge the extent of this worrisome scenario, the purpose of this paper is to attempt to investigate the factors, including credit attitudes, knowledge on credit card, materialism, social norm and self-efficacy, that influence credit card misuse amongst Gen Y in Malaysia. Design/methodology/approach: The authors have collected responses from a total of 501 respondents in two urban areas in Malaysia and estimated six multiple regression models to test five hypotheses. Findings: The results suggest that credit card knowledge and self-efficacy are negatively related to credit card misuse amongst Gen Y in Malaysia. In contrast, positive relationships were found to exist between credit card attitudes, materialism and social norm and the dependent variable. Research limitations/implications: In this study, the authors limit the data collection to the two biggest urban areas in Malaysia, namely, Klang Valley and Ipoh. Practical implications: For the regulator’s perspective, the results can be used to understand the alarming indebtedness behaviour amongst working members of Gen Y and outline appropriate and effective policies to reduce their serious indebtedness. Financial service providers, however, can collaborate with regulators to curb credit card misuse amongst Gen Y, so that the latter can avoid high bad debt from line of credit facilities and bankruptcy. Originality/value: The study’s findings will further enrich the existing literature on the factors affecting the credit card misuse, especially for the unique Gen Y cohort in Malaysia
Self-plasticizing membrane based on Co(II)-porphyrin modified with silver nanoparticles for thiocyanate detection
No full textA novel potentiometric anion-selective self-plasticizing polymeric membrane based on 5,10,15,20-tetrakis-(4-methoxyphenyl)-21H,23H-porphyrin cobalt(II) (CoTMeOPP)-silvernanoparticle- modified glassy carbon electrode (GCE) was examined for use in the detection of thiocyanate anions. The membrane was characterized by X-ray diffraction (XRD) analysis, field-emission electron microscopy, UV-visible diffused reflectance spectroscopy, and fluorescence spectroscopy. The prepared ion-selective sensor exhibited a positive Nernstian response and deviated from the classical Hofmeister selective pattern with a significantly sensitive and enhanced response towards the thiocyanate anion. It exhibited a rapid response of 3 s with a low detection limit of 9.55 × 10-8 M within the concentration range from 1 × 10-1 to 1 × 10-7 M. The sensor also showed a high selectivity for the thiocyanate anion over a variety of anions. The influence of the additives was studied and this sensor was successfully applied to the potentiometric titration of silver nitrate and the direct determination of the amount of thiocyanate anions in a wide array of samples of river water, ex-mine lake sediment, human saliva, and fish
Analysis of Water Treatment by Moringa oleifera Bioflocculant Prepared Via Supercritical Fluid Extraction
No full textIn this study, we used supercritical fluid extraction to prepare Moringa oleifera as a bioflocculant and studied its efficacy in water treatment. Relative to the conventional solvent extraction method, supercritical fluid extraction produced 42% more bioflocculant and was a more efficient method with both time (about seven hours less) and cost savings (about USD30 less). The bioflocculant produced via supercritical fluid extraction was also smaller (18±5 µm) and more similar in size (Coefficient of Variation, CV = 28%) as opposed to conventional solvent extraction (23±8 µm, CV = 35%). It was able to reduce more than 95% of turbidity and up to 60% bacterial population. Its performance in reducing selected heavy metals from water samples was also generally better than aluminium sulfate or alum. Our study showed that with the exception of cost restrictions, M. oleifera bioflocculant produced via supercritical fluid extraction has the potential to replace alum in water treatment plants
A high efficient dual-output rectifier for piezoelectric energy harvesting
No full textIn this paper, a high efficient active NMOS dual-output rectifier for piezoelectric energy harvesting (PEH) in CMOS technology is proposed. The rectifier adopts a cross-coupled active NMOS topology producing two output DC voltages. A DC-DC combiner at the rectifier's output is employed to sum the output DC voltages which improves the effective Voltage Conversion Efficiency (VCE) and Power Conversion Efficiency (PCE). Simulated on a standard 65-nm CMOS technology, the proposed rectifier achieves a VCE > 98% across a connected output load of Rrec > 9 kΩ and a peak PCE of ∼84% for Rrec = 12 kΩ. Compared to conventional piezoelectric rectifiers, the PCE of the proposed rectifier is significantly improved with comparative VCE performance
Plasticized solid polymer electrolyte based on natural polymer blend incorporated with lithium perchlorate for electrical double-layer capacitor fabrication
No full textA plasticized solid polymer electrolyte system is prepared using polymer blend of methyl cellulose–potato starch with lithium perchlorate (LiClO4) as dopant salt and glycerol as plasticizer. Transport properties of the electrolytes are investigated using electrical impedance spectroscopy (EIS). By applying a method proposed by Arof et al. which was found to be suitable for both Arrhenius and Vogel–Tammann–Fulcher (VTF) type of electrolytes, the number density (n), diffusion coefficient (D), and mobility (μ) of ions are found to be influenced by the concentration of glycerol. From ion and electron transference number analysis, it is verified that ions are the main charge carriers. Linear sweep voltammetry (LSV) verifies the suitability of the most conductive electrolyte to be employed in the carbon-based symmetric electrical double-layer capacitor (EDLC) fabrication. The EDLC has been tested using the galvanostatic charge–discharge and cyclic voltammetry (CV) techniques. The specific capacitance (Csp) of the electrode using CV at a sweep rate of 2 mV s−1 is found to be 61.58 F g−1. The EDLC has been tested for 1000 charge–discharge cycles with the highest Csp value of 28.04 F g−1. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
Co-occurrence of acute ophthalmoplegia (without ataxia) and idiopathic intracranial hypertension
No full textBackground: Acute ophthalmoparesis without ataxia was designated as ‘atypical Miller Fisher syndrome’ as it presents with progressive, relatively symmetrical ophthalmoplegia, but without ataxia nor limb weakness, in the presence of anti-GQ1b antibody. Idiopathic intracranial hypertension is characterized by signs of raised intracranial pressure occurring in the absence of cerebral pathology, with normal composition of cerebrospinal fluid and a raised opening pressure of more than 20 cmH2O during lumbar puncture. We aim to report a rare case of acute ophthalmoplegia with co-occurrence of raised intracranial pressure. Case Description: A 28-year-old gentleman with body mass index of 34.3 was referred to us for management of double vision of 2 weeks duration. His symptom started after a brief episode of upper respiratory tract infection. His best corrected visual acuity was 6/6 OU. He had bilateral sixth nerve palsy worse on the left eye and bilateral hypometric saccade. His deep tendon reflexes were found to be hyporeflexic in all four limbs. No sensory or motor power deficit was detected, and his gait was normal. Plantar reflexes were downwards bilaterally and cerebellar examination was normal. Both optic discs developed hyperaemia and swelling. Magnetic resonance imaging of brain was normal and lumbar puncture revealed an opening pressure of 50 cmH2O. Anti-GQ1b IgG and anti-GT1a IgG antibody were tested positive. Conclusion: Acute ophthalmoparesis without ataxia can present with co-occurrence of raised intracranial pressure. It is important to have a full fundoscopic assessment to look for papilloedema in patients presenting with Miller Fisher syndrome or acute ophthalmoparesis without ataxia. © The Author(s) 2018
Curved text detection in blurred/non-blurred video/scene images
No full textText detection in video/images is challenging due to the presence of multiple blur caused by defocus and motion. In this paper, we present a new method for detecting texts in blurred/non-blurred images. Unlike the existing methods that use deblurring or classifiers, the proposed method estimates degree of blur in images based on contrast variations in neighbor pixels and a low pass filter, which results in candidate pixels for deblurring. We consider gradient values of each pixel as the weight for the degree of blur. The proposed method then performs K-means clustering on weighted values of candidate pixels to get text candidates irrespective of blur types. Next, Bhattacharyya distance is used to extract symmetry property of texts to remove false text candidates, which provides text components. Further, the proposed method fixes bounding box for each text component based on the nearest neighbor criteria and direction of the text component. Experimental results on defocus, motion, non-blurred images and standard datasets of curved text show that the proposed method outperforms the existing methods. © 2019, Springer Science+Business Media, LLC, part of Springer Nature
Senescent HUVECs-secreted exosomes trigger endothelial barrier dysfunction in young endothelial cells
No full textAccumulation of senescent endothelial cells can cause endothelium dysfunction which eventually leads to agerelated vascular disorders. The senescent-associated secretory phenotype (SASP) cells secrete a plethora of soluble factors that negatively influence the surrounding tissue microenvironment. The present study sought to investigate the effects of exosomes, which are nano-sized extracellular vesicles known for intercellular communications secreted by SASP cells on young endothelial cells. Exosomes were isolated from the condition media of senescent human umbilical vein endothelial cells (HUVECs) and then confirmed by the detection of exosome specific CD63 and CD9 expressions, electron microscopy and acetylcholinesterase assay. The purified exosomes were used to treat young HUVECs. Exposure to exosomes repressed the expression of adherens junction proteins including vascular endothelial (VE)-cadherin and beta-catenin, decreased cell growth kinetics and impaired endothelial migration potential of young endothelial cells. These findings suggest that senescent HUVECs-secreted exosomes could disrupt barrier integrity that underpins endothelial barrier dysfunction in healthy young endothelial cells. © 2019, Leibniz Research Centre for Working Environment and Human Factors. All rights reserved
Preliminary Techno–Environment–Economic Evaluation of an Innovative Hybrid Renewable Energy Harvester System for Residential Application
No full textA technical, environmental, and economic feasibility study for a patented hybrid renewable energy harvester system for residential application is conducted in this paper. This system can be mounted on top of an existing residential building to provide electricity from renewable sources. The system is characterized by its V-shaped roof guide vane (VRGV) that directs and augments airflow into the wind turbine, to enhance the rotational and power generation performance of the wind turbines in low wind speed areas. Furthermore, the VRGV increases the installation area for the solar photovoltaic panels and expand the rainwater collection area for the building, and facilitates natural ventilation and prevents excessive solar radiation into the room. The environment-economic evaluation of the system is conducted based on the life-cycle cost (LCC) in terms of low carbon and economic cost-effectiveness. The evaluation of the system with dimensions of 15 m (L) × 16 m (W) × 17.05 m (H) showed that the annual energy generated is 21.130 MWh. Annual low-carbon benefit of the system is estimated to be 11.894 t. The cumulative net present value (NPV) of the system in the life cycle time (20 years) is $52,207.247, with the consideration of a discount rate of 8%; also, the cash flow breakeven occurs in the 11th year. It is important to note that the carbon payback period (CPP) of the system is five years. © 2019 by the authors
Students’ perceptual quality standards for judging knowledge quality: Development and validation of a perceived e-learning knowledge quality scale
No full textThis study examines the factors contributing towards eLearning knowledge quality based on students’ perspective and presents a 5-dimensional scale to evaluate knowledge quality (KQ). It is an extension of our previously published research which had proposed a novel conceptual KQ model. In this paper, we attempt to quantify knowledge quality (KQ), as opposed to adapting data quality (DQ) and information quality (IQ) measurement tools. A qualitative-quantitative sequential mixed-method design was used for the instrument validation. Data was collected at two levels, undergraduate and postgraduate respectively. Exploratory and confirmatory factor analysis confirmed the 5 dimensional second-order perceived eLearning KQ model – comprising of 33 sub-dimensions. The scale is inclusive of five key dimensions (Intrinsic KQ, Contextual KQ, Representational KQ, Accessible KQ, and Actionable KQ) as measures of quality of knowledge gained from eLearning content. The proposed dimensions are the benchmarks that provide insight to educators and administrators in developing and enhancing e-learning content. © The Author(s) 2017