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Vehicle logo recognition using whitening transformation and deep learning
No full textThis paper presents a vehicle logo recognition using a deep convolutional neural network (CNN) method and whitening transformation technique to remove redundancy of adjacent image pixels. Backpropagation algorithm with stochastic gradient descent optimization technique has been deployed to train and obtain weight filters of the networks. Seven layers of our proposed CNN incorporating an input layer, five hidden layers and an output layer have been implemented to capture rich and discriminative information of vehicle logo images. Functioning as the output layer of the network, the softmax classifier is utilized to handle multiple classes of vehicle logo image. For a given vehicle logo image, the network provides the probability for each vehicle manufacturer to which the given logo image belongs. Unlike most of the common traditional methods that employ handcrafted visual features, our proposed method is able to automatically learn and extract high-level features for the classification task. The extracted features are discriminative sufficiently to perform well in various imaging conditions and complex scenes. We validate our proposed method by utilizing a public vehicle logo image dataset, which comprises 10,000 and 1500 vehicle logo images for training and validation objective, respectively. Experimental results based on our proposed method outperform other existing methods in terms of the computational cost and overall classification accuracy of 99.13%. © 2018, Springer-Verlag London Ltd., part of Springer Nature
Year Five Pupils’ Number Sense and Algebraic Thinking: the Mediating Role of Symbol and Pattern Sense
No full textThis study mainly focused on the relationship between number sense and algebraic thinking. Previous studies have provided evidence that number sense plays an important role in developing algebraic thinking. The role of symbol and pattern sense are yet to discover in relation to number sense and algebraic thinking. The purpose of this study was to identify the mediating effects of symbol sense and pattern sense in year five pupils’ relationship between number sense and algebraic thinking. To do so, two mathematics tests were carried out among 720 year five pupils in the district of Malacca, Malaysia. The collected data were analysed using a partial least squares-struc-tural equation modeling approach. The data collected were analysed using SPSS 22.0 and SmartPLS 3.0. Results demonstrated that symbol sense and pattern sense are good mediators between year five pupils’ number sense and algebraic thinking. This result of this study supports the past studies related to the role of number sense, symbol and pattern sense in developing algebraic thinking. The presented study provides suggestions as intervention to increase students’ making sense ability in numbers, symbols and patterns to develop algebraic thinking. © 2019, Adam Marszalek Publishing House. All rights reserved
Simultaneous determination of ethanol and methanol in alcohol free malt beverages, energy drinks and fruit juices by gas chromatography
No full textA simple, sensitive, and direct method to decide if "alcohol-free" beverages, energy drinks and fruit juices could result in positive "alcohol alerts" based on the use of the gas chromatography with a flame ionization detector (GC- FID) has been developed. The chromatographic conditions such as injection volume and split ratios were optimized in order to increase the sample throughput and sensitivity. Unlike other conventional methods which also employ laborious sample preparations; this method analyzes samples directly without any prior treatment and thus cutting down the sample treatment time, as well as reducing the analysis cost per sample. Additionally, low ethanol concentrations as low as 6 mg/L were detected and quantified; making this method an appropriate technique for routine alcohols analysis in beverages. Optimization of chromatographic conditions gave recoveries in the range of 83.00% to 112.8% with relative standard deviations lower than 9%. The calibration curves were linear over the range from 6.250-200.0 mg/L for methanol and ethanol. The correlation coefficients (r2) were higher than 0.9997. The limits of quantifications (LOQ) are 4.48 mg/L for ethanol and 5.74 mg/L for methanol. A total of 100 domestic and imported labeled "alcohol-free" in Jordan were analyzed for their alcohol content. Concentrations ranged from non-detectable to 14.9 mg/L for ethanol and from non-detectable to 9.38 mg/L for methanol were found in energy drinks. On the other hand, non- quantifiable amounts of alcohols were found in malt beverage as well as fruit juices. © 2019, Asian Journal of Agriculture and Biology
Highly sensitive ethanol sensor based on TiO2 nanoparticles and its photocatalyst activity
No full textPhoto-catalytic decolorization or adsorption of an aqueous solution of 3 ppm of brilliant cresyl blue (BCB) in a suspension of 0.26 gm/100 ml of TiO 2 metal oxide semiconductor as a catalyst, was achieved by using 200Watts UV lamp from an external source. The disappearance of the original colored dye concentration with irradiation time was monitored using UV-VIS Spectrophotometer. It was found that 74% of BCB dye was degraded after 120 min of irradiation time. In addition, the sensing properties of the TiO 2 films were examined on behalf of numerous concentrations of ethanol in the liquid phase by a straightforward and dependable I–V procedure at normal room conditions. The sensitivity of the sensor was found to be ˜0.052 mAM −1 cm -2 for ethanol. Thus, the degradation rate and the subsequent chemical sensing properties of TiO 2 nanoarchitecture are of immense importance for the functions of TiO 2 structure as a photo-catalyst and chemical sensor. © 2019 Elsevier Gmb
A novel method of determining breast cancer risk using parenchymal textural analysis of mammography images on an Asian cohort
No full textHistorically, breast cancer risk prediction models are based on mammographic density measures, which are dichotomous in nature and generally categorize each voxel or area of the breast parenchyma as 'dense' or 'not dense'. Using these conventional methods, the structural patterns or textural components of the breast tissue elements are not considered or ignored entirely. This study presents a novel method to predict breast cancer risk that combines new texture and mammographic density based image features. We performed a comprehensive study of the correlation of 944 new and conventional texture and mammographic density features with breast cancer risk on a cohort of Asian women. We studied 250 breast cancer cases and 250 controls matched at full-field digital mammography (FFDM) status for age, BMI and ethnicity. Stepwise regression analysis identified relevant features to be included in a linear discriminant analysis (LDA) classifier model, trained and tested using a leave-one-out based cross-validation method. The area under the receiver operating characteristic (AUC) and adjusted odds ratios (ORs) were used as the two performance assessment indices in our study. For the LDA trained classifier, the adjusted OR was 6.15 (95% confidence interval: 3.55-10.64) and for Volpara volumetric breast density, 1.10 (0.67-1.81). The AUC for the LDA trained classifier was 0.68 (0.64-0.73), compared to 0.52 (0.47-0.57) for Volpara volumetric breast density (p < 0.001). The regression analysis of OR values for the LDA classifier also showed a significant increase in slope (p < 0.02). Mammographic texture features derived from digital mammograms are important quantitative measures for breast cancer risk assessment based models. Parenchymal texture analysis has an important role for stratifying breast cancer risk in women, which can be implemented to routine breast cancer screening strategies. © 2019 Institute of Physics and Engineering in Medicine
Mangrove derived Streptomyces sp. MUM265 as a potential source of antioxidant and anticolon-cancer agents
No full textBackground: Colon cancer is the third most commonly diagnosed cancer worldwide, with a commensurately high mortality rate. The search for novel antioxidants and specific anticancer agents which may inhibit, delay or reverse the development of colon cancer is thus an area of great interest; Streptomyces bacteria have been demonstrated to be a source of such agents. Results: The extract from Streptomyces sp. MUM265 - a strain which was isolated and identified from Kuala Selangor mangrove forest, Selangor, Malaysia - was analyzed and found to exhibit antioxidant properties as demonstrated via metal-chelating ability as well as superoxide anion, DPPH and ABTS radical scavenging activities. This study also showed that MUM265 extract demonstrated cytotoxicity against colon cancer cells as evidenced by the reduced cell viability of Caco-2 cell line. Treatment with MUM265 extract induced depolarization of mitochondrial membrane potential and accumulation of subG 1 cells in cell cycle analysis, suggesting that MUM265 exerted apoptosis-inducing effects on Caco-2 cells. Conclusion: These findings indicate that mangrove derived Streptomyces sp. MUM265 represents a valuable bioresource of bioactive compounds for the future development of chemopreventive agents, with particular promise suggested for treatment of colon cancer. © 2019 The Author(s)
Evaluating the physicochemical properties and efficacy of recently expired and aged antivenom products from Thailand and Taiwan
No full textGel filtration chromatography and gel electrophoresis revealed minimal protein degradation in lyophilized antivenoms which were 2-year expired (Hemato Polyvalent, Neuro Polyvalent; Thailand) and 18-year expired (Hemato Bivalent, Neuro Bivalent; Taiwan). All expired antivenoms retained immunological binding activity, and were able to neutralize the hemotoxic or neurotoxic as well as lethal effects of the homologous snake venoms. The findings show that antivenoms under proper storage conditions may remain relatively stable beyond the indicated shelf life. © 2019 Elsevier Lt
Energy Band Gap Modulation in Nd-Doped BiFeO3/SrRuO3 Heteroepitaxy for Visible Light Photoelectrochemical Activity
No full textThe ability of band offsets at multiferroic/metal and multiferroic/electrolyte interfaces in controlling charge transfer and thus altering the photoactivity performance has sparked significant attention in solar energy conversion applications. Here, we demonstrate that the band offsets of the two interfaces play the key role in determining charge transport direction in a downward self-polarized BFO film. Electrons tend to move to BFO/electrolyte interface for water reduction. Our experimental and first-principle calculations reveal that the presence of neodymium (Nd) dopants in BFO enhances the photoelectrochemical performance by reduction of the local electron-hole pair recombination sites and modulation of the band gap to improve the visible light absorption. This opens a promising route to the heterostructure design by modulating the band gap to promote efficient charge transfer. © 2018 American Chemical Society
Exploring the Electronic Properties of Ribonucleic Acids Integrated Within a Schottky-Like Junction
No full textDeoxyribonucleic acid (DNA), being the main biomolecule of life, has been studied extensively in terms of its electronic properties, charge transport mechanisms and potential use in nano-electronic devices. The ability of DNA to self-replicate, self-assemble and mediate charge transfer has made it an interesting molecule to multidisciplinary researchers. However, not much attention has been given to ribonucleic acid (RNA), which is an equally important biomolecule that shares some common features with DNA. Elucidation of RNA’s electronic behavior could provide more information regarding its electronic properties, potentially offering a new biomolecule for application in bioelectronics. In this work, RNA samples integrated within two metal electrodes were subjected to positive and negative bias potentials and their resulting current profiles were investigated. Interestingly, current rectification similar to electric field-induced semi-conductive behavior of conventional Schottky junctions was observed for all RNA samples tested, indicating highly characteristic RNA-specific Schottky profiles. A non-linear profile was observed from the current–voltage (I–V) characteristics of gold (Au)-RNA-Au structures showing resemblance to metal-DNA structures investigated previously. Various solid-state parameters such as turn-on voltage, shunt resistance, series resistance and ideality factor were also calculated to further understand the biomaterial’s solid-state behavior. These results successfully demonstrated the exciting observation of the semi-conductive-like behavior of RNA which could be utilized as a tool in molecular electronics. © 2019, The Minerals, Metals & Materials Society
Entamoeba infections and associated risk factors among migrant workers in peninsular Malaysia
No full textThe influx of low skilled migrant workers to Malaysia from low socio-economic countries where gastrointestinal parasitic infections are prevalent has raised concerns about transmission to the local population. Three methods for detection (serology, microscopy and molecular techniques) were utilized to identify Entamoeba infections amongst the targeted cohort and determine risk factors associated with infection. Serological screening of 484 migrant workers from five working sectors in Peninsular Malaysia using IgG4 ELISA based on the rPPDK antigen showed an overall seroprevalence of 7.4% (n = 36; CL95 = 5.3–10.1%) with only one factor statistically associated with seropositivity of anti-amoebic antibodies, i.e. years of residence in Malaysia (χ21 = 4.007, p = 0.045). Microscopic examination of 388 faecal samples for protozoan cysts and trophozoites showed a slightly higher prevalence (11.6%; n=45; CL95: 8.4–14.8%). Meanwhile, amplification of the 16S rDNA gene detected two species i.e. Entamoeba dispar (23/388; 5.9%; CL95: 3.6–8.3%) and E. histolytica (11/388; 2.8%; CL95: 1.2–4.5%) and mixed infections with both parasites in only three samples (3/388; 0.8%; CL95: 0.2–2.2%). Entamoeba dispar infection was significantly associated with those employed in food and domestic services (χ24 = 12.879, p = 0.012). However, none of the factors affected the prevalence of E. histolytica infection. Despite the low prevalence of E. histolytica in faecal samples of the study cohort, the presence of this pathogenic parasite still poses potential public health risks and calls for tighter control strategies based on better availability of chemotherapeutic treatment and accessibility to appropriate health education. © 2019, Malaysian Society for Parasitology. All rights reserved