• Journal of the Korean earth science society
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• v.25 no.3
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• pp.194-204
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• 2004

The purpose of this literature review is to investigate what kinds of research have been done about scientific inquiry in terms of scientific argumentation in the classroom context from the upper elementary to the high school levels. First, science educators argued that there had not been differentiation between authentic scientific inquiry by scientists and school scientific inquiry by students in the classroom. This uncertainty of goals or definition of scientific inquiry has led to the problem or limitation of implementing scientific inquiry in the classroom. It was also pointed out that students' learning science as inquiry has been done without opportunities of argumentation to understand how scientific knowledge is constructed. Second, what is scientific argumentation, then? Researchers stated that scientific inquiry in the classroom cannot be guaranteed only through hands-on experimentation. Students can understand how scientific knowledge is constructed through their reasoning skills using opportunities of argumentation based on their procedural skills using opportunities of experimentation. Third, many researchers emphasized the social practices of small or whole group work for enhancing students' scientific reasoning skills through argumentations. Different role of leadership in groups and existence of teachers' roles are found to have potential in enhancing students' scientific reasoning skills to understand science as inquiry. Fourth, what is scientific reasoning? Scientific reasoning is defined as an ability to differentiate evidence or data from theory and coordinate them to construct their scientific knowledge based on their collection of data (Kuhn, 1989, 1992; Dunbar & Klahr, 1988, 1989; Reif & Larkin, 1991). Those researchers found that students skills in scientific reasoning are different from scientists. Fifth, for the purpose of enhancing students' scientific reasoning skills to understand how scientific knowledge is constructed, other researchers suggested that teachers' roles in scaffolding could help students develop those skills. Based on this literature review, it is important to find what kinds of generalizable teaching strategies teachers use for students scientific reasoning skills through scientific argumentation and investigate teachers' knowledge of scientific argumentation in the context of scientific inquiry. The relationship between teachers' knowledge and their teaching strategies and between teachers teaching strategies and students scientific reasoning skills can be found out if there is any.

• Korean Journal of Health Education and Promotion
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• v.19 no.1
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• pp.17-30
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• 2002

BACKGROUND: Back pain is a popular disease in general population as well as in workers. School students handle heavy bag and keep awkward postures during class long time. However, the prevalence of back pain among students and the risk factors associated with back pain are not well known. METHODS: In this study, we assess the frequency of risk factors for back pain among 2,717 high school students. From April 2001 to May 2001, using a self-reported questionnaire, we collected data on occurrence of back pain and potential risk factors for back pain. RESULTS: Fifteen percent of high school students reported having daily back pain for a week or more during the past 12 months. Female students had a higher prevalence of back pain than males(OR=2.22, 95% CI 1.69-2.91). Using a multiple logistic regression model, we found six factors associated with back pain for females; alcohol(OR=1.75, 95% CI 1.26-2.45), depression(OR=1.75, 95% CI 1.84-2.28), poor physical health(OR=2.57, 95% CI 1.84-8.58), obesity(OR=0.29, 95% CI 0.12-0.68), exercise(OR=l.50, 95% CI=1.07-2.16), and good performance(OR=l.50, 95% CI 1.05-2.18). Only alcohol, however, associated with back pain for males(OR=1.70, 95% CI 1.05-2.77) CONCLUSIONS: High school students had a relatively high prevalence of back pain. Students with alcohol consumption had the higher risk for back pain.

• BMB Reports
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• v.53 no.6
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• pp.291-298
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• 2020

Tumor angiogenesis is an essential process for growth and metastasis of cancer cells as it supplies tumors with oxygen and nutrients. During tumor angiogenesis, many pro-angiogenic factors are secreted by tumor cells to induce their own vascularization via activation of pre-existing host endothelium. However, accumulating evidence suggests that vasculogenic mimicry (VM) is a key alternative mechanism for tumor vascularization when tumors are faced with insufficient supply of oxygen and nutrients. VM is a tumor vascularization mechanism in which tumors create a blood supply system, in contrast to tumor angiogenesis mechanisms that depend on pre-existing host endothelium. VM is closely associated with tumor progression and poor prognosis in many cancers. Therefore, inhibition of VM may be a promising therapeutic strategy and may overcome the limitations of anti-angiogenesis therapy for cancer patients. In this review, we provide an overview of the current anti-angiogenic therapies for ovarian cancer and the current state of knowledge regarding the links between microRNAs and the VM process, with a focus on the mechanism that regulates associated signaling pathways in ovarian cancer. Moreover, we discuss the potential for VM as a therapeutic strategy against ovarian cancer.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1184-1193
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• 2015

Monitoring for megalocytivirus infection was conducted for ten months from March to December in 2013 in 15 aquatic farms culturing, red sea bream, rock bream, rock fish and black sea bream around Tongyoung coastal area in Korea, to assess spatial and temporal variability of detection prevalence, and to explore possible links with seawater temperature. In nested-PCR targeted major capsid protein (MCP) gene, asymptomatic megalocytivirus infection was detected in the externally healthy farmed fish with a significant prevalence in range from 0 to 58.3% for ten months. Higher prevalence of megalocytivirus (46.7% - 57.1%) was observed in high water temperature season from September to November than that in other months with lower prevalence of 0.0% to 20.0%. Even though an acute infection of megalocytivirus was occurred in rock bream (positive in the first PCR) with high mortality in one of fifteen farms, there was no expansion or transmission of the disease to the rock fish and red sea bream culturing in net cage just proximal to the rock bream cage in which disease outbreaked. Nucleotide sequence analysis of the cloned MCP gene isolated asymptomatically infected rock fish revealed that the megalocytivirus in this study was clustered together with the rock bream iridovirus (RBIV) under the subgroup II of the genus megalocytivirus (Iridoviridae), which is known to be the major megalocytivirus strain in Korea. The typical histopathological signs were not found in the spleen of rock fish asymptomatically infected by megalocytivirus. Experimental infection of rock bream with the spleen homogenate of the rock fish infected asymptomatically did not induce any mortality unlike the homogenate of infected rock bream with hih mortlity. However, these results may suggest that the asymptomatic infection of megalocytivirus in other fish species can be a potential risk threatening aquaculture industries as a transmission factor of megalocytivirus to susceptible fish species, especially rock bream.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.6
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• pp.1662-1672
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• 2016

To address physicochemical factors of yellow clay for removing Cochlodinium polykrikoides blooms, the correlation of removal efficiency with mineralogical characteristics of yellow clay collected from various areas was surveyed. Yellow clay from different localities showed the wide range of chemical compositions $SiO_2$ : 43~71%, $Al_2O_3$ : 13~26%, $Fe_2O_3$ : 5~14%, MgO : 0.4~1.8%, $K_2O$ : 0.6~3.3%, L.O.I.(Loss of Ignition) : 4.5~15%. The mineral compositions of yellow clay were mainly consisted of quartz and feldspar including small amounts of kaolinite, chlorite, and Fe-oxides. The result of size analysis showed that $6{\Phi}(31{\sim}16{\mu}m)$ and $7{\Phi}(16{\sim}8{\mu}m)$ were dominated sizes. The zeta-potential were in the range of -4.1~-20.7mV(average -13.7). As increasing removal efficiency of C. polykrikoides, contents of $Al_2O_3$, $Fe_2O_3$ and L.O.I. in yellow clay increased, whereas $SiO_2$ content decreased. Furthermore, the amounts of silt mineral and small particle were high when the removal efficiency was high. According to factor analysis using principle component analysis, two components of factor 1 and factor 2 showed 79% of the total variance, which is related to cohesion and adsorption. Inducing cell lysis of C. polykrikoides by cohension and adsorption between C. polykrikoides and yellow clay.

• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.31-36
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• 1989

The second-order rate constants for the nucleophilic substitution reactions of para-substituted benzyl nitrates with para-substituted anilines in acetonitrile were conductometrically determined. Hammett ${\rho}$x and ${\rho}$y values and Bronsted ${\beta}$ values were obtained from these kinetic data. The reactions of Benzyl nitrates with the series of anilines showed linear Hammett plots with negative slopes. For the change of substituents in the benzyl nitrates, nonlinear Hammett plots with a concave upwards curve were obtained. We applied the potential energy surface and the quantum mechanical models in order to examine the transition state variations caused by changes in substituents on the nucleophile and the substrate. The results showed that the reaction was proceeded via the $S_{N}2$-type reaction mechanism in which the extent of bond-formation was greatly changed depending on the property of the substituents in substrate.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.3
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• pp.413-426
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• 2005

The objective of this study consists of facilitating seafood consumption by increasing its intake opportunities for consumer through analysis of sliced raw fish. A study on sliced raw fish consumption was conducted on 630 citizens of Busan(252 men and 378 women), attending high school and university, and employedas housekeepers and salaried employees. The goal of the study was to assess the attitude and degree of satisfaction obtained from eating sliced raw fish and ultimately to promote greater seafood consumption. A self-administered questionnaire was used to record the results. The results were as follows : About sixty percent of the respondents appeared to like or not to be reluctant to eating sliced raw fish. The main reasons for favoring sliced raw fish were its taste and nutritious effects. All ages liked sliced raw fish, but teenaged women, on average, tend to dislike sliced raw fish. The most preferred sliced raw fish was flounder. Most of the panelists preferred korean rock fish, and red sea bream due to their ordinary muscle. Sliced raw fish of the 2nd and 3rd variety were the most popular. For most of the sliced raw fish, the own-price elasticity came out to be relatively low. This can be explained by the fact that sliced raw fish is characteristically purchased based more on quality and freshness, than on price. SINGSINGWHE(SSW)-fresh sliced raw fish should be stored at 0$^{\circ}C$ for no longer than 10hrs. Taste, nutritional value and low price have the potential to promote the consumption of seafood. Factors which can reduce the consumption of sliced raw fish were safety due to Vibrio septicemia, rainy day, indistinct origin, and high rices. To promote sliced raw fish consumption, the subjects recommended the quality improvement and low price.

• Korean Journal of Health Education and Promotion
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• v.26 no.3
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• pp.75-83
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• 2009

Objectives: This study aims to examine if the follow-up management service by National Health Insurance (NHI) for obesity persons leads to significant modification of the lifestyle and change of health status. Methods: Of persons who underwent health screening and were classified as obesity after periodic health screening by NHI in 2004, persons who took the follow-up management service were selected as case group and persons who took no service were selected as control group. The DW database of NHI was used to explore the effect of the follow-up management service on the modification of lifestyle and health status. Chi-square tests and t-tests, pairs t-tests were conducted with SAS 9.1 to examine the differences of health promotion effect between case vs. control group. Results: It was shows that of lifestyle behaviors, only exercise is significantly improved for case group compared with control group as the effect of the follow-up management service by NHI (2.11%p) (p=0.0435). Further, morbidity rate for control group was 2.05% higher than that of case group (p=0.0002). These results indicate that persons who received the follow-up management service better maintained their health significantly than persons who did not. Conclusion: The present study shows that the appropriate follow-up management services need to be provided for maximaizing potential effect of periodic health screening by NHI.

• Korean Journal of Construction Engineering and Management
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• v.19 no.4
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• pp.70-81
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• 2018

Claims in the construction industry can have a serious impact on the profitability of the project or can even result in project failure if it fails to take appropriate prevention. In order to properly prevent and respond to the potential claims and legal disputes throughout the project execution, it is necessary to continuously accumulate informations and clearly define the roles and responsibilities of the important activities systematically. Based on these needs, this study develops and verifies the project information management system(PMIS) that can prevent and respond possible claims for construction projects. Developed system includes such management modules as schedule, cost, PM/CM, design, collaboration, and claims. The system was validated by adopting it to the practical projects. The results showed that information systems tailored to the construction claim need to elevate users' familiarity to be more useful. Besides, the system can be more functional when used by both owners and contractors.

• Preventive Nutrition and Food Science
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• v.15 no.3
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• pp.213-220
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• 2010

To examine the potential of Terminalia chebula as a whitening agent, we measured antioxidant activity using DPPH$\cdot$, ABTS${\cdot}^+$ assays and ferric-reducing antioxidant power (FRAP) assays, and depigmenting activity using B16F10 melanoma cells. The intracellular reactive oxygen species (ROS) level was monitored by $H_2DCFDA$ fluorescence labeling, and melanin contents in B16F10 melanoma cells by 960 $J/m^2$ dose of UVA-induced oxidative stress. The radical-scavenging activities of T. chebula extract (TCE) were measured in terms of $EC_{50}$ values using DPPH$\cdot$, ABTS${\cdot}^+$ assays and FRAP value were 280.0 ${\mu}g/mL$, 42.2 ${\mu}g/mL$ and 113.1 ${\mu}mol$ $FeSO_4{\cdot}7H_2O/g$, respectively. We found that ROS and melanin concentrations were reduced by TCE treatments of 25 ${\mu}g/mL$ under UVA-induced oxidative stress. Tyrosinase activity and melanin contents in $\alpha$-melanocyte stimulating hormone (MSH)-induced melanoma cells both decreased dose-dependently in the treatment groups. TCE similarly reduced melanogenesis in B16F10 melanoma cells stimulated by $\alpha$-MSH as compared to arbutin as a positive control. T. chebula may prove to be a useful therapeutic agent for hyperpigmentation and an effective component in skin whitening and.or lightening cosmetics.