• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.290-303
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• 2011

The purpose of this study was to introduce the practical model on the enhancement of the divergent and convergent thinking skills through inquiry instruction in science class. In this study, the creative thinking skill has been defined by divergent thinking skill as the narrow sense. In the science field, the problem solving thinking skill is just same as the inquiry thinking skill. Also, the problem solving thinking skill has been defined by convergent thinking skill as the critical thinking skill. This new instruction had been used for the college student in the class of general chemistry laboratory for the one semester. The first results had been founded that the students' divergent thinking skill had been increased significantly. Especially, the skills of recognition of problems, the skills of making hypothesis, and the skills of transformation and interpretation of data had been increased significantly. The second results had been founded that the students' convergent thinking skill had been increased significantly. Especially, the skills of making hypothesis, the skills of transformation and interpretation of data, and the skills of making conclusion and generalization had been increased significantly. The third results had been founded that the students' the creative and problem solving thinking skill had been increased significantly. Especially, the rest of all skills exception the skill of control variables had been increased significantly.

• Journal of Crop Science and Biotechnology
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• v.10 no.2
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• pp.112-116
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• 2007

Kinetin(KN) is an inducer of rice(Oryza sativa L.) defense/stress responses, as evidenced by the induction of inducible secondary metabolite and defense/stress protein markers in leaf. We show a novel light-dependent effect of KN-triggered defense stress responses in rice leaf. Leaf segments treated with KN(100 ${\mu}M$) show hypersensitive-like necrotic lesion formation only under continuous light illumination. Potent accumulation of two phytoalexins, sakuranetin and momilactone A(MoA) by KN that peaks at 48 h after treatment under continuous light is completely suppressed by incubation under continuous dark. Using two-dimensional gel electrophoresis we identified KN-induced changes in ribulose-1, 5-bisphosphate carboxylase/oxygenase, energy- and pathogenesis-related proteins(OsPR class 5 and 10 members) by N-terminal amino acid sequencing and mass spectrometry. These changes were light-inducible and could not be observed in the dark(and control). Present results provide a new dimension(light modulation/regulation) to our finding that KN has a potential role in the rice plant self-defense mechanism.

• Journal of The Korean Association For Science Education
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• v.27 no.4
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• pp.318-327
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• 2007

The purpose of this study is to examine the effects of small-scale chemistry(SSC) laboratory activities implemented in high school chemistry II classes on the students' inquiry process skills and science-related attitudes. For this study, 112 students in the 12th grade were chosen and divided into an experimental and a control group. Seven SSC lab programs that can replace the traditional experiments in chemistry II textbooks were selected and administered to the experimental group while the traditional textbook experiments were administered to the control group. The results showed that there was a significant difference in the enhancement of inquiry process skills between the two groups while no significant difference was found in science-related attitudes. Further analysis showed that the difference in the inquiry process skills came from the basic inquiry process skills. The experimental group students thought that the SSC experiments have many advantages compared to the traditional experiments, e.g., individual work, learning lab and theory in parallel, short experiment time, safety, environmental aspects, etc. These results suggest that the SSC lab programs are valuable in high school chemistry classes and developing and distributing various SSC lab programs is needed to replace the traditional experiments in the current textbooks.

• Journal of Environmental Science International
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• v.17 no.9
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• pp.981-992
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• 2008

This study examined how to produce new methods of copper (II) sulfate crystallization by using a small-scale chemistry tool such as small-scale reaction surface and petri dish. The making of copper(II) sulfate is included in the 5th grade elementary science textbooks. Various copper(II) compounds were reacted with a 2 M sulfuric acid solution. The result of this study is as follows: Seven small amounts of copper(II) compounds were reacted with a few drops of 2 M sulfuric acid solution at room temperature to make a copper(II) sulfate crystal of triclinic shape. Using the petri dish method, a copper(II) sulfate crystal could be identified within one hour of reacting copper(II) hydroxide, copper(II) carbonate, copper(II) nitrate, copper(II) perchlorate, cupric(II) formate from a few drops of 2 M sulfuric acid solution at room temperature. When using the lap top method for copper(II) perchlorate, cupric formate, a proper crystal could be identified within one hour as well. SSC methods were used for the first time to make a copper sulfate crystal via chemical reaction. We can make a copper(II) sulfate crystal using a simple method which is easier, safer and saves time in class. And since a small quantity of chemicals are being used in SSC chemical methods, waste is greatly reduced. This lessens the amount of environmental problems caused by the experiment. This can be helpful in preserving nature. In addition the cost of chemical and laboratory equipment is greatly reduced because it uses material that we find in our daily lives. There will be continued study of small-scale methods such as improvement of new programs, study and training of teachers, and securing SSC tools. I would like to suggest such as SSC methods are applicable in elementary School Science. I would like it to become a wide spread program.

• Journal of Microbiology and Biotechnology
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• v.20 no.1
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• pp.21-29
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• 2010

The phenolic compounds are a major contaminant class often found in industrial wastewaters and the biological treatment is an alternative tool commonly employed for their removal. In this sense, monitoring microbial community dynamics is crucial for a successful wastewater treatment. This work aimed to monitor the structure and activity of the bacterial community during the operation of a laboratory-scale continuous submerged membrane bioreactor (SMBR), using PCR and RT-PCR followed by denaturing gradient gel electrophoresis (DGGE) and 16S rRNA libraries. Multivariate analyses carried out using DGGE profiles showed significant changes in the total and metabolically active dominant community members during the 4-week treatment period, explained mainly by phenol and ammonium input. Gene libraries were assembled using 16S rDNA and 16S rRNA PCR products from the fourth week of treatment. Sequencing and phylogenetic analyses of clones from the 16S rDNA library revealed a high diversity of taxa for the total bacterial community, with predominance of Thauera genus (ca. 50%). On the other hand, a lower diversity was found for metabolically active bacteria, which were mostly represented by members of Betaproteobacteria (Thauera and Comamonas), suggesting that these groups have a relevant role in the phenol degradation during the final phase of the SMBR operation.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.771-780
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• 2010

The purpose of this study is to examine the effects of PBL (Problem-based Learning) strategy applied to the "Inorganic Chemistry Laboratory" class. Especially, the changes in 'self-directed learning ability' and 'attitudes toward science' of undergraduate students were examined. In addition, perception on PBL problem and the PBL classes were investigated. The results of this study were as follows: First, after the course, 'self-directed learning ability' and 'attitude toward science' of students were significantly improved (p < .05). There were significant improvements in every sub-categories except 'self-confidence as a learner' for 'self directed learning ability' and every sub-categories except 'usefulness of science' for 'attitude toward science'. Second, the students expressed that PBL strategy provided opportunities to learn self-directively and responsibly, but the process of defining the problem was difficult. Finally on the survey toward PBL strategy, the students responded that PBL problems were authentic and helpful to learn problem solving ability. In conclusion, PBL laboratory course is effective for developing self-directed learning ability and positive attitude toward science.

• Analytical Science and Technology
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• v.24 no.6
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• pp.435-442
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• 2011

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants (BFRs) which have taken much interest recently due to their potential hazardous effects to human body and ecosystem. Many countries and European community prohibits the usage of certain BFRs in electronics and electronic devices (e.g. RoHS). In this perspectives, Korea Research Institute of Standards and Science (KRISS) has designed and practiced proficiency testing programs based on the ISO/IEC 17043 in order to assist laboratory accreditation activities. The programs for interlaboratory comparisons include congeners of PBDE (PBDE-154, 183, 206, 209) in high impact polystyrene (HIPS). A sample bottle that contains 10 g granular HIPS was distributed to 35 participating laboratories and the test results were calculated by the statistical procedure using z-scores to evaluate performance of each laboratory. The results and the laboratory's performance were discussed.

• Journal of Science Education
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• v.38 no.2
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• pp.302-316
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• 2014

The purpose of this study is to devise a Small-Scale Chemistry (SSC) lab program for primary school learners and to examine its effects on science learning achievement. In addition, it will be examined whether the type of learning groups affects the achievement or not. The participants in the current study were 173 6th graders from 6 classes of Y elementary school in Changwon city, Gyeongnam. Three classes(86) were assigned to the experimental group and the other three, the comparative group after checking the pre-homogeneity between the two groups through t-test on the scores of the science mid-term exam. We conducted five experimental sessions on the Acid and Base in the science textbook for the sixth graders. The students of one experimental class worked in pairs and another class worked individually, but the students of the comparative classes were divided into groups of six(one group with pair, another group with individual work in the SSC program, and the other group conducting the traditional experiment with groups of six students). The data were analyzed by t-test and ANOVA. The results showed that experimental learning using individual work in the SSC program compared to traditional experimental learning was effective in improving science learning achievement. also it was indicated that the teachers could reduce their burden of preparing for classes and of school hours when they utilized the SSC laboratory learning program. Teachers could also actively support students' experimental activities in employing the program. Based on the results, we suggest that the development of the SSC laboratory learning program is meaningful in the sense that this program can help elementary schoolers to improve science learning achievements more than the existing traditional experimental methods.

• Biomedical Science Letters
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• v.2 no.2
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• pp.223-229
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• 1996

HLA-B27 gene, one of the HLA-class I molecule, is strongly associated with ankylosing spondylitis. It has been most frequently used as a disease-correlated HLA gene by clinicians. In most laboratories, conventional HLA-B27 typing is still performed by cell cytotoxicity tests or fluorescence serology with specific antibodies. In this study, DNA typing method for HLA-B27 was developed by using group specific Polymerase Chain Reaction (PCR). Four HLA-B27 cell lines (HOM-2, JESTHOM, WT24 and BTB) and fifty six B27 Korean individuals defined by serology were used. The results of control cell and B-27 positive individual samples were correlated well with the data which was performed by serological method. All of B27 positive PCR products gave positive signals on Southern blot hybridization with B27 specific probe. This study shows that the HLA-B27 DNA typing is a relatively simple, fast and practical tool for the determination of the HLA-B27 gene in routine clinical laboratory work.

• Biomedical Science Letters
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• v.4 no.1
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• pp.11-25
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• 1998

The HLA genes located in the short arm of chromosome 6 specify heterodimeric glycoproteins involved in the regulation of the immune response. Recently, in the elucidation of HLA polymorphism, serological and cellular typing methods have been replaced by DNA typing using polymerase chain reaction (PCR). The purpose of this study was to establish the HLA DNA typing methods and determine gene frequencies of HLA molecules in Koreans. PCR-SSP (sequence specific primers) and PCR-RFLP (restriction fragment length polymorphism) techniques were used for the analysis of HLA-A, -B, -C, DRBl genes and HLA-DQAl, DQBl, DPBl genes, respectively. The results of B-lymphoblastoid cells used for control experiment were consistent with the previous data identified in the 11th International Histocompatibility Workshop. Seventeen, 23, 16, 8, 16, 13 and 37 types of HLA-A, B, C, DQAl, DQBl, DPBl and DRBl alleles were found, respectively, in a total of unrelated 120 Korean individuals. The most frequent HLA alleles were $A^*$02 (27.0%), B$^*$40 (17.6%), Cw$^*$01 (19.2%), DQAl$^*$0301 (32.1%), DQBl$^*$0303 (12.9%), DPBl$^*$0501 (31.3%) and DRBl$^*$1501 (9.2%) among Koreans. This study shows that DNA typing method using PCR technique is a relatively simple, fast and practical tool for the determination of the HLA-class I and II genes. Moreover, the data of HLA gene frequencies could be useful for the Korean database before clinical applications, including organ and unrelated bone marrow transplantation, anthropological study, disease association and individual identification.