A phytochemical investigation of the bark of Alseodaphne peduncularis (Wall. Ex. Ness) Meissn (Lauraceae) has resulted in the isolation of a known aporphine alkaloid; boldine (1). The isolation and purification of the alkaloids were achieved using column chromatography (CC) and preparative thin layer chromatography (PTLC). The structural elucidation was performed by spectral methods mainly 1D and 2D NMR, IR, UV and MS, and in comparison with data from other literature...

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The isolation and purification of the leaves extract of Alseodaphne corneri Kosterm yielded four alkaloids; norisocorydine 1, isocorydine 2, 2-norobamegine 3 and obamegine 4. This phytochemical study involves extraction, separation by using various chromatographic methods and structural determination by spectroscopic technique such as ultraviolet spectroscopy (UV), infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR) including 1D-NMR (1H, 13C and DEPT), 2D-NMR (COSY, NOESY, HMQC/HSQC, and HMBC) and mass spectrometry (MS). The IC50 value of antiplasmodial activity for isocorydine 2 and obamegine 4 are 0.50 μmolL-1 and 0.14 μmolL-1 respectively...

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A phytochemical study on the leaf extract of Alseodaphne corneri Kosterm involving extraction, separation by using various chromatographic methods and structural determination by spectroscopic technique such as ultraviolet spectra (UV), infrared spectra (IR), nuclear magnetic resonance (NMR) and mass spectra (MS) was carried out. The isolation and purification from the leaves of Alseodaphne corneri Kosterm yielded two aporphines: norlirioferine and lirioferine...

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The objectives of this study are to extract and isolate the alkaloids from two species of Alseodaphne; Alseodaphne peduncularis (Wall. ex Nees) Meisn from Kluang- Mersing, Johor and Alseodaphne corneri Kosterm from University Malaya, Kuala Lumpur. The extraction process of the plant material started by cold percolation process using hexane to remove non-polar organic compounds, waxes and fats. The plant material then re-extracted by dichloromethane using soxhlet extractor followed by acid-base extraction to get the alkaloid crude extract. The isolation and purification of alkaloids from the crude extract were done by using various chromatographic techniques including column chromatography and preparative thin layer chromatography. The elucidation of the isolated alkaloids were determine by using various spectroscopic methods such as 1D NMR (1H, 13C and DEPT) and 2D NMR (COSY, HMQC and HMBC), ultraviolet (UV), infrared (IR) and mass spectrometry (MS). The structures were further confirm.....

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The main objective of this research is to compute the nonabelian tensor squares of some Bieberbach groups with elementary abelian 2-groups point groups, C2×C2 for both abelian and nonabelian cases. This is qualitative research where the computational method for polycyclic groups is used to determine the nonabelian tensor squares of four Bieberbach groups with point group C2 × C2. The findings show that the structures of the nonabelian tensor squares of some of these groups for both abelian and nonabelian cases are found split while some are found non-split. The formulas of the abelian cases of the nonabelian tensor squares of the groups lead to the construction of the formulations of the nonabelian tensor squares of arbitrary dimension. Furthermore, for the nonabelian cases, the presentations of the nonabelian tensor squares of the other two groups are given and it was shown that the nonabelian tensor squares can be written as a direct product with the nonabelian exterior square as o.....

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Delphi method which is a technique and structured approach used to review and collect opinions of a group of experts, has its own weaknesses. The Fuzzy Delphi Method (FDM), derived from modifications of Delphi Method introduced by Kaufman and Gupta in 1988, is considered by many researchers as more superior in providing evidence of human linguistic system (which is the signature of Delphi Technique). In this paper, FDM was used to assess the key components and contents of an instructional module based on multiple intelligences (MI-Based Instructional Module). This development phase is part of a project to develop a MI-Based Instructional Module for 4 years old preschool children in Malaysia. This phase involves the views of 10 experts who are experienced in teaching preschool children and have deep knowledge in early childhood education. It is a rigorous statistical analysis to validate the validity of abstract concept of the MI-Based Instructional Module. Experts are required to valid.....

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This study aimed to explore and enlist factors of academic stress among primary school students. A qualitative exploratory research which utilized focus group interviews as a mean of collecting data was carried out. A total of 80 primary school students were selected from two public primary schools in Kuala Lumpur and one private primary school in Selangor. Students were divided into groups of 10 students each for focus group interviews. The data was analyzed using Interpretative Phenomenological Analysis (IPA). Results from analysis revealed six superordinate themes of academic stress among primary school students; (1) Teachers related stress, (2) Family and home environment related stress, (3) School related stress, (4) Stress arise from hectic schedule, (5) Stress due to excessive leisure activities and (6) Peers related stress. There were also fourteen sub-themes. As a conclusion, some of the academic stress issues experienced by primary school students were common issues.....

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