A phytochemical investigation of the stem bark of Calophyllum canum resulted in the isolation of a new xanthone dimer identified as biscaloxanthone (1), together with four compounds; trapezifoliaxanthone (2), trapezifolixanthone A (3), taraxerone (4) and taraxerol (5). The structures of these compounds were determined via spectroscopic methods of IR, UV, MS and NMR (1D and 2D). The cytotoxicity of compounds 1-3 were screened against A549, MCF-7, C33A and 3T3L1 cell lines, wherein weak cytotoxic activities were observed (IC50 > 50 ?m). 2020 Walter de Gruyter GmbH, Berlin/Boston 2020...

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Given the rapid development of dehazing image algorithms, selecting the optimal algorithm based on multiple criteria is crucial in determining the efficiency of an algorithm. However, a sufficient number of criteria must be considered when selecting an algorithm in multiple foggy scenes, including inhomogeneous, homogenous and dark foggy scenes. However, the selection of an optimal real-time image dehazing algorithm based on standardised criteria presents a challenge. According to previous studies, a standardisation and selection framework for real-time image dehazing algorithms based on multi-foggy scenes is not yet available. To address this gap, this study proposes a new standardisation and selection framework based on fuzzy Delphi (FDM) and hybrid multi-criteria analysis methods. Experiments are also conducted in three phases. Firstly, the image dehazing criteria are standardised based on FDM. Secondly, an evaluation experiment is conducted based on standardised criteria and nine r.....

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This paper introduces the concept of triangular citation that combines direct citation, co-citation and bibliographic coupling, and defines three kinds of literature used in triangular citation, namely, original Literature A, intermediary Literature B and following Literature C. Taking citation data from the CNKI database as the experimental sample, it was found that there are triangular citations in the actual citation network, with a high coverage rate. Additionally, the authors analyzed the triangular citation sample data from the different perspectives of reference time, literature type, impact factor, interdisciplinary citation, and the author's self-citation, thereby finding the external characteristics of literature and internal trends of citation in the triangular citation. Additionally, it was concluded that the literature between A and C has an "indirect citation"mechanism. The citation characteristics of the two, i.e., A and C, are different from the direct citation relation.....

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Driver behavior is a concerning issue in the area of intelligent transportation system (ITS). Driver behavior is a significant key player in a wide range of unpleasant events during the ride, such as accidents or crashes, traffic congestion, harsh braking, and acceleration/deceleration. Influencing factors of driver behavior have been explored in several studies. It is imperative to investigate these factors in order to provide a comprehensive analysis and to categorize them on the basis of a coherent taxonomy. With that, this study conducted a systematic review on prior studies that focused on bus driver behavior, particularly in the ITS. This study also established a taxonomy on the topic of driver behavior in multiple areas of ITS and their classifications. Different databases, namely ScienceDirect, Web of Science, and IEEE Explore, were utilized to obtain relevant articles from 2008 to 2021 (15 April). Several filtering and scanning stages were performed according to the exclusion/.....

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The Logistic Regression Model (LRM) is successful in many fields due to its capability of predicting and describing the relationship between binary response variables and one or more independent variables. However, the prediction results of this model are still not accurate enough due to error terms, regardless of their existence in the model. To overcome this problem and, at the same time, produce more accurate and efficient predictive model values, the bootstrap approach was proposed. Unfortunately, this approach did not receive any attention, especially for this model. This study aims to introduce the bootstrap approach to LRM and investigate the performance of the proposed models using data on wound healing using jellyfish collagen. The results revealed that the proposed model generated smaller values of MSE and RMSE, as well as shorter confidence intervals, compared with the existing LRM. These results proved that the proposed model could produce an estimated value that is more ac.....

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The study aimed at developing and evaluating a simple green electrochemistry experimental kit named Lectrofun 2.0. Lectrofun 2.0 is an educational kit equipped with a module built with the criteria of user-friendly, cost-effective, and laboratory free. The basic concept of electrochemistry was introduced through a guided learning approach via the module. The objectives of this research were to (1) develop Lectrofun 2.0 module using green chemicals, recyclable and easily accessible materials and (2) evaluate the module effectiveness in terms of student achievement/understanding of the Electrochemistry topic. This is a Design and Development Research (DDR) using the ADDIE model as an instructional design model. The development phase involves the first objective of the study, while the evaluation phase involves the second objective. Total of 46 respondents of pre-post tests were involved in evaluating effectiveness of Lectrofun 2.0 in terms of student achievement/understanding of the topi.....

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The pandemic of Covid-19 has caused a shift of paradigm of education, from face-to-face to e-learning. E-learning leads to an escalation in digitalization of handwritten documents because it requires submission of homework and assignments through online. To help teachers in checking digitalized handwritten homework, this paper proposes an automatic checking system based on a convolutional neural network (CNN) for handwritten numeral recognition. The CNN is used to recognize four arithmetic operations in mathematical questions consisting of addition, deduction, multiplication and division. The performance CNN in handwritten numeral recognition have been optimized in terms of activation function and gradient descent algorithm. The proposed CNN is also trained and tested with the MNIST handwritten data set. The experimental results show that the recognition accuracy the improved CNN improves to a certain extent as compared to before optimization. ? 2021 The Authors. Published by Elsevier .....

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Oral tradition refers to the dissemination of cultural materials through oral or oral discourse. Elements like history, literature, and other cultural heritage are transmitted across generations. However, limited scholarly attention has been devoted to mapping the overview of this research area. Thus, this study addresses the shortcoming by mapping the current trend of the study on oral tradition. The data extracted from Scopus database has been analysed using bibliometric analysis. The search using keywords related to oral tradition has extracted about 486 documents over 100 years for publication analysis. The research productivity is reported together along with document and source type, language, country/region, active institution publishing, author, subject area, keyword and publication distribution of citation analysis. The data of 132 years has shown an increament of development rate of literature on the oral tradition from 1888 until 2020. The results show that various studies h.....

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Recent years, the top 3 of world's export products were monopolized by Electronic and Electrical sector. In Malaysia, Electronic and Electrical is the main contributor of export since 1980s. However, the export performance of Malaysian Electronic and Electrical is often affected by several issues including competitors, financial crisis and global pandemic crisis. Hence, this article aims to investigate the relationship between Malaysian electronic and electrical export value and exchange rate using Bayesian method to fit a two components normal mixture model. Bayesian parameter estimation method is getting popular in time series data analysis due to its asymptotic properties which is then furnishes reliable results. Through Bayesian analysis, the finding reveals that there is a positive relationship between Malaysian electronic and electrical export value with exchange rate. Meanwhile, Malaysian Electronic and Electrical export price increase when there is an appreciation of exchange r.....

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This needs analysis was conducted to gauge the extent to which a 5E Inquiry-Based Science Teaching Module is required by primary science teachers. A review of the literature indicates that questionnaires were prevalently used to elicit teachers' view on the needs for certain teaching materials such as modules. Accordingly, a questionnaire was developed and it consists of three pre-determined constructs, namely (a) Teacher's knowledge, (b) Teacher's skill, (c) Teacher's needs (towards a teaching module). The questionnaire has sufficient validity and reliability to be used as a research instrument. The questionnaire was then formatted in an online survey and sent to WhatsApp groups of primary science teachers. After two-week duration, 62 science teachers responded to the online questionnaire. Analysis of the data indicates that the corresponding self-reported means for Teacher's knowledge, Teacher's skills, and Teacher's needs for a teaching module are 3.77, 3.78, and 4.23 respectively. .....

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