• Journal of the Korean Society of Earth Science Education
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• v.12 no.1
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• pp.109-118
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• 2019

The purpose of this study was to investigate the effects of experience as a science experiment assistant teacher on the science instruction anxiety and the science teaching efficacy beliefs of elementary pre-service teachers in a small scale school. For this study, 21 elementary pre-service teachers were selected and then they worked as science experiment assistant teachers in small scale schools for about 10 months. They were tested the science instruction anxiety and the science teaching efficacy beliefs in before and after. After analyzing the tests results, some pre-service teachers were interviewed. The results of this study are as follows. The experiences as science experiment assistant teachers positively influenced on reducing the science instruction anxiety to elementary pre-service teachers. The experiences also had positive effects on reducing both state anxiety and trait anxiety, which are the sub-factors of science instruction anxiety. In addition, the science teaching efficacy beliefs and its sub-factor, the self-efficacy in science teaching, had positive impacts, but the experiences did not have a positive impact on the outcome expectancy. The effects of the experience as a science experiment assistant teacher were different according to the personal experiences and cognitions of pre-service teachers.

• Biomedical Science Letters
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• v.10 no.3
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• pp.219-230
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• 2004

This experiment was performed to examine the in vitro and in vivo affects of the two different haplotype strains of mice, BALB/c and C3H/HeN infected with Echinostoma hortense, and the manifestation of the profiles of cytokine in the splenocytes. In the in vitro experiment, the two mice's splenocytes were divided and stimulated with antigen of crude extracts and the antigen of excretory and secretory products of an adult warm and the manifestation of cytokine mRNA was verified with RT-PCR. As a result, the two different strains of mice both strongly manifested the Th2 cytokine rather than the Thl cytokine and in the case of the Th2 cytokine, the BALB/c mice manifested more strongly than the C3H/HeN mice. In the experiment using the ELISA method, the protem cytokine manifestation had the same result as the mRNA experiment. In the in vivo experiment, the mice was infected via oral route with the metacercaria of the Echinostoma hortense and the manifestation of cytokine was verified by RT-PCR and ELISA and the results were the same as the in vitro experiment. Therefore, in the two strains of BALB/c and C3H/HeN, the C3H/HeN showed a higher susceptivity to the Echinostoma hortense.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.1
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• pp.53-56
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• 2001

Barley Yellow Dwarf Virus (BYDV), an aphid-borne luteovirus, is a major plant pathogenic disease causing a huge economic loss in the grain production of a wide range of Gramineae species throughout the world. It has been recently reported that BYDV also occurred frequently in wheat field of Korea. Here, we performed to develop the detection and classification methods of BYDV strains that were accomplished by reverse transcription-polymerase chain reaction (RT-PCR). Since there are high variations among BYDV strains, three pairs of primers were designed to detect BYDV strains such as PAV (Vic-PAV and CN-PAV) and MAV (primer A) simultaneously, specifically Vic-PAV(primer B), and MAV (primer C) based on the genomic RNA sequences of BYDV strains previously published. The validity of the primers was confirmed using several BYDV strains obtained from CIMMYT. Though three BYDV strains were able to be detected using primer A, PCR products were not distinguished between two PAV strains. It was possible to separate them with a restriction enzyme, EcoRI, whose restriction site was present in the amplified DNA fragment from Vic-PAV, but not from CN-PAV.

• Journal of Korean Elementary Science Education
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• v.33 no.1
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• pp.181-194
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• 2014

The purpose of this study was to analyze the difference between eye movements according to science achievement of elementary school students on measuring tasks. Science achievement was graded by the results of Korea national achievement test conducted in 2012. As an assessment tool to check measuring task, two measuring measure problems from TSPS(Test of Science Process Skill; developed in 1994) which were suitable for eye tracking system were adopted. The subjects of this study were 3 underachievers and 3 overachievers from 6th grade who agreed to participate in the research. SMI was used to collect EMD (eye movement data). Experiment 3.2 and BeGaze 3.2 programs were used to plan experiment and analyze EMD. As a result, eye movements of participants in measuring task did not show the path to the common gaze by groups. To solve the problem of using specific measuring strategies related to the correct answer. Underachiever who failed in measuring tasks don't have enough measurement capabilities and lack eye movement through the area of interest for cognitive thinking. These results show that elementary school science curriculum dealing with measuring have to reflect a lot of step-by-step learning requires.

• Toxicological Research
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• v.24 no.3
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• pp.227-233
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• 2008

To detect lead ions using electrochemical voltammetric analysis, Infrared Photo-Diode Electrode(IPDE) was applied via cyclic and square wave stripping voltammetry. Lead ions were deposited at 0.5 V(versus Ag/AgCl) accumulation potential. Instrumental measurements systems were made based on a simple and compact detection system. The stripping voltammetric and cyclic voltammetric optimal parameters were searched. The results yielded a cyclic range of $40{\sim}240mgl^{-1}$ Pb(II) and a square wave stripping working range of $0.5{\sim}5.00mgl^{-1}$ Pb(II). The relative standard deviation at 2 and 4 $mgl^{-1}$ Pb(II) was 0.04% and 0.02%(n=15), respectively, using the stripping voltammetric conditions. The detection limit was found to be 0.05 $mgl^{-1}$ with a 40 sec preconcentration time. Analytical interference ions were also evaluated. The proposed method was applied to determine lead ions in various samples.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.75-75
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• 2022

Traditional agriculture mostly focused on activity in the field, but current agriculture faces problems such as reduction of agricultural inputs, labor shortage and so on. Accordingly, traditional agricultural experiments generally considered the simple treatment effects, but current agricultural experiments need to consider the several and complicate treatment effects. To analyze such several and complicate treatment effects, data collection has the first priority. Remote sensing is a quite effective tool to collect information in agriculture, and recent easier availability of UAVs (Unmanned Aerial Vehicles) enhances the effectiveness. LAI (Leaf Area Index) is one of the most important information for evaluating the condition of crop growth. In this study, we utilized UAV with multispectral camera to evaluate plant-based LAI of sweetcorn in a small-scale field experiment and discussed the feasibility of a new experimental design to analyze the several and complicate treatment effects. The plant-based SR measured by UAV showed the highest correlation coefficient with LAI measured by a canopy analyzer in 2018 and 2019. Application of linear mix model showed that plant-based SR data had higher detection power due to its huge number of data although SR was inferior to evaluate LAI than the canopy analyzer. The distribution of plant-based data also statistically revealed the border effect in treatment plots in the traditional experimental design. These results suggest that remote sensing with UAVs has the advantage even in a small-scale experimental plot and has a possibility to provide a new experimental design if combined with various analytical applications such as plant size, shape, and color.

• Journal of the Korean Society of Earth Science Education
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• v.4 no.1
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• pp.43-56
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• 2011

The purpose of this study is to examine the effects of small group inquiry skills on improving science process skills and attitudes toward science in elementary school science. The research questions of this study were as follows. First, effects of small group inquiry skills on improving science process skills in elementary school science. Second, effects of small group inquiry skills on improving attitudes toward science in elementary school science. The subjects of this study is two classes from 6th grade elementary classes in Busan. The experiment class practiced small group inquiry skills, while the control class practiced self inquiry. To verify the effect of the experiment, ANOVA was conducted. The main findings of this study are as follows. First, the small group inquiry skills gave a significant influence on increasing the science process skills, including the basic science process skills and the integrated science process skills, of students. Especially, among subordinate factors of science process skills between groups, it was effective to increase abilities of observing, reasoning, interpreting data, formulating hypothesis. It is necessary for teachers to make an effort to teach according to steps of the small group inquiry skills and to support inquiry activities, in order to increasing the science process skills. However, frequency of additional lessons have a little influence on increasing the science process skills. Second, there is meaningful change in the attitudes toward science for those who studied the small group inquiry skills. Also, they affected subordinate factors of the attitudes toward science, like the attitudes toward science inquiry, the happiness about science class. This study shows that the small group inquiry skills give a positive influence on the science process skills and attitudes toward science in elementary school science.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.681-689
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• 2023

Purpose: Muons are characterized by a strong penetrating ability and can travel through thousands of meters of rock, making them ideal to image large volumes and substances typically impenetrable to, for example, electrons and photons. The feasibility of 3D image reconstruction and material identification based on a cosmic ray muons tomography (MT) system with triangular bar plastic scintillator detectors has been verified in this paper. Our prototype shows potential application value and the authors wish to apply this prototype system to 3D imaging. In addition, an MT experiment with the same detector system is also in progress. Methods: A simulation based on GEANT4 was developed to study cosmic ray muons' physical processes and motion trails. The yield and transportation of optical photons scintillated in each triangular bar of the detector system were reproduced. An image reconstruction algorithm and correction method based on muon scattering, which differs from the conventional PoCA algorithm, has been developed based on simulation data and verified by experimental data. Results: According to the simulation result, the detector system's position resolution is below 1 ~ mm in simulation and 2 mm in the experiment. A relatively legible 3D image of lead bricks in size of 20 cm × 5 cm × 10 cm used our inversion algorithm can be presented below 1× 10⁴ effective events, which takes 16 h of acquisition time experimentally. Conclusion: The proposed method is a potential candidate to monitor the cosmic ray MT accurately. Monte Carlo simulations have been performed to discuss the application of the detector and the simulation results have indicated that the detector can be used in cosmic ray MT. The cosmic ray MT experiment is currently underway. Furthermore, the proposal also has the potential to scan the earth, buildings, and other structures of interest including for instance computerized imaging in an archaeological framework.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.2
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• pp.281-290
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• 1993

This experiment was designed to evaluate the effect of degree of unsaturation (Experiment 1) and the chain length of constituent fatty acids of dietary fats (Experiment 2) on-3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activities in the liver and small intestine of chicks. Chicks were fed experimental diets for 10 days and then killed for the determination of the HMG-CoA reductase activities in the intestinal epithelial cell and hepatic microsomes. The hepatic HMG-CoA reductase activity showed the highest value in chicks fed the tallow-containing diet. Chicks fed diets containing safflower or coconut oil resulted in a significantly lower intestinal HMG-CoA reductase activity in comparison with those fed the olive oil-containing diet. The hepatic HMG-CoA reductase activity was significantly higher when fat-free and trilaurin were fed than when any other triglycerides were fed. This activity showed the lowest value in the chicks fed the diet containing tristearin. The HMG-CoA reductase activities in the jejunum and ileum were significantly or tended to be higher when trilaurin was fed than when any other triglycerides were fed. Except when trilaurin was fed, the presence of saturated fat in the diet did not have a significant effect on the intestinal HMG-CoA reductase activity, unlike the effect shown when a highly unsaturated fat was added to the diet. There was no significant correlation between the HMG-CoA reductase activities of the liver and intestinal, and the HMG-CoA reductase activity and cholesterol content of the intestinal epithelial cells.

• Journal of The Korean Association For Science Education
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• v.21 no.3
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• pp.566-579
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• 2001

The purpose of this study was to investigate students' actual thinking processes during conceptual change about free fall. To do this, middle school students were made an interview designed based on a teaching model using thought experiment. From the study, it was found that strategy for generating cognitive conflict by suggesting opposite views was not effective. However, many students changed their prior conceptions when new explanatory hypothesis, which explained why heavy object and light object fall equally, was introduced. And finally, even though students realized that the changed idea did not accord with the real world, they could easily solve that problem by observing demonstration designed to show the effect of air resistance.