SCOPUS 1999-2004
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Item Exopolysaccharide-producing lactic acid bacteria strains from traditional thai fermented foods: Isolation, identification and exopolysaccharide characterization(1999) T. Smitinont; C. Tansakul; S. Tanasupawat; S. Keeratipibul; L. Navarini; M. Bosco; P. Cescutti; T. Smitinont; Natl. Ctr. for Genet. Eng./Biotech., Natl. Sci./Technol. Devmt. Agency, Rajdhevee, Bangkok 10400, 73/1 Rama VI Road, Thailand; email: thita@biotec.or.thLactic Acid Bacteria (LAB) isolated from various traditional Thai fermented foods were screened for exopolysaccharides (EPS) production. From 104 isolates, two rod-shaped and five coccal-shaped LAB were able to produce EPS from sucrose on solid media. However, only the cocci were capable of producing EPS in liquid media and these were identified as Pediococcus pentosaceus. Pediococcus pentosaceus strains AP-1 and AP-3 produced EPS in high yield. In liquid media containing sucrose as carbon source, the amount of EPS produced by AP-1 and AP-3 strains was 6.0 and 2.5 g/L, respectively. The isolated and purified EPSs were chemically characterized. On the basis of sugar composition, methylation analysis and nuclear magnetic resonance spectroscopy, both the EPSs were shown to belong to the same dextran class. In particular, both EPSs differed from linear dextran by branching through 3,6-di-Osubstituted _-d-glucopyranosyl residues. The EPS from P. pentosaceus AP-3 was characterized by a relatively higher degree of branching and by a higher molecular weight than that from P. pentosaceus AP-1.Item Student attitudes to learning business statistics: Comparison of online and traditional methods(International Forum of Educational Technology and Society,National Taiwan Normal University, 2004) Pannee Suanpang; Peter Petocz; Walter Kalceff; P. Suanpang; Faculty of Science and Technology, Rajabhat Suan Dusit University, Bangkok, 10300, Thailand; email: dtechpannee@yahoo.comWorldwide, electronic learning (E-learning) has become an important part of the education agenda in the last decade. The Suan Dusit Rajabhat University (SDRU), Thailand has made significant efforts recently to use Internet technologies to enhance learning opportunities. The results reported here are part of a pioneering study to determine the effectiveness of a new online learning course in the subject "Business Statistics". This paper compares two groups of students, one studying using a traditional lecture-based approach, and the other studying using e-learning. The comparison is based on students' attitudes towards statistics measured using a validated questionnaire, both before and after the 16-week course, and for each of the modes of study. Comparisons are also made with students studying by distance, although the numbers in these groups are too small for sensible statistical analysis. The questionnaire data are augmented by material from interviews and other student reports of their experience. The results showed highly significant differences in attitudes towards statistics between the students studying online and the students using a traditional approach.Item Ultrastructural alterations in the liver and kidney of white sea bass, Lates calcarifer, in acute and subchronic cadmium exposure(2004) Suchada Thophon; Prayad Pokethitiyook; Kashane Chalermwat; E. Suchart Upatham; Somphong Sahaphong; P. Pokethitiyook; Department of Biology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; email: grpph@mahidol.ac.thUltrastructural alterations in the liver and kidney of 3-month-old white sea bass, Lates calcarifer, after cadmium exposure were studied by transmission electron microscopy (TEM). One group of fish was exposed to a cadmium concentration of 10 mg/L (acute) for 96 h in a static system, and another group was exposed to cadmium concentrations of 0.8 and 3 mg/L cadmium (subchronic) for 3 months in a recirculation closed system. Ultrastructural alterations observed in the hepatocytes included mitochondrial condensation, swelling, and lysis. The rough endoplasmic reticulum (RER) showed dilation, fragmentation, and vesiculation. After subchronic exposure there were numerous large lipid droplets and abundant stored glycogen. Ultrastructural alterations observed in the proximal tubules of the kidney included nuclear degeneration, condensation, and massive swelling of the mitochondria; RER fragmentation and vesiculation. Disorganized brush borders and increased numbers of large hydropic vacuoles and lysosomes were also observed. © 2004 Wiley Periodicals, Inc.