• Journal of Science Education
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• v.47 no.2
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• pp.192-210
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• 2023

This study was intended to develop the plant molecular biology experimental program using Rapid-cycling Brassica rapa (RcBr) based on the teaching steps and teaching methods of the cognitive apprenticeship model and to determine its application effects. In order to improve a subject's cognitive function and expertise on molecular biology experiments, two themes composed of a total 8 class sessions were selected: 'Identification of DFR gene in purple RcBr and non-purple RcBr' and 'Identification of RcBr's genetic polymorphism site using the DNA profiling method'. Research subjects were 18 pre-service teaching majors in biology education of H University in Chungbuk, Korea. The effectiveness of the developed program was verified by analyzing the enhancement of 'cognitive function' related to the use of molecular biology knowledge and technology, and the enhancement of 'domain-general metacognitive abilities.' The effect of the developed program was also determined by analyzing the task flow diagram provided. The developed program was effective in improving the cognitive functions of the pre-service teachers on the use of knowledge and technology of molecular biology experiments. It was especially effective to improve the higher cognitive function of pre-service teachers who did not have the previous experience. The developed program also showed a significant improvement in the task of metacognitive knowledge and in the planning, checking, and evaluation of metacognitive regulation, which are sub-elements of domain-general metacognitive abilities. It was found that the developed program's self-test activity could help the pre-service teachers to improve their metacognitive regulation. Therefore, this developed program turned out to be helpful for pre-service teachers to develop core competencies needed for molecular biology experimental classes. If the teaching and learning materials of the developed program could be reconstructed and applied to in-service teachers or high school students, it would be expected to improve their metacognitive abilities.

• Korean Journal of Ecology and Environment
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• v.56 no.1
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• pp.45-56
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• 2023

In stream ecosystem assessment, RIVPACS, which makes a simple but clear evaluation based on macroinvertebrate community, is widely used. In this study, a preliminary study was conducted to develop a RIVPACS-type model suitable for Korean streams nationwide. Reference streams were classified into two types(upstream and downstream), and a prediction model for macroinvertebrates was developed based on each family. A model for upstream was divided into 7 (train): 3 (test), and that for downstream was made using a leave-one-out method. Variables for the models were selected by non-metric multidimensional scaling, and seven variables were chosen, including elevation, slope, annual average temperature, stream width, forest ratio in land use, riffle ratio in hydrological characteristics, and boulder ratio in substrate composition. Stream order classified 3,224 sites as upstream and downstream, and community compositions of sites were predicted. The prediction was conducted for 30 macroinvertebrate families. Expected (E) and observed fauna (O) were compared using an ASPT biotic index, which is computed by dividing the BMWPK score into the number of families in a community. EQR values (i.e. O/E) for ASPT were used to assess stream condition. Lastly, we compared EQR to BMI, an index that is commonly used in the assessment. In the results, the average observed ASPT was 4.82 (±2.04 SD) and the expected one was 6.30 (±0.79 SD), and the expected ASPT was higher than the observed one. In the comparison between EQR and BMI index, EQR generally showed a higher value than the BMI index.

• Resources Recycling
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• v.31 no.6
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• pp.44-51
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• 2022

In the steelmaking process using an electric arc furnace (EAF), light-burnt dolomite, which is a flux containing MgO, is used to protect refractory materials and improve desulfurization ability. Furthermore, a recarburizing agent is added to reduce energy consumption via slag foaming and to induce the deoxidation effect. Herein, a waste MgO-C based refractory material was used to achieve the aforementioned effects economically. The waste MgO-C refractory materials contain a significant amount of MgO and graphite components; however, most of these materials are currently discarded instead of being recycled. The mass recycling of waste MgO-C refractory materials would be achievable if their applicability as a flux for steelmaking is proven. Therefore, experiments were performed using a target composition range similar to the commercial EAF slag composition. A pre-melted base slag was prepared by mixing SiO₂, Al₂O₃, and FeO in an alumina crucible and heating at 1450℃ for 1 h or more. Subsequently, a mixed flux #2 (a mixture of light-burnt dolomite, waste MgO-C based refractory material, and limestone) was added to the prepared pre-melted base slag and a melting reaction test was performed. Injecting the pre-melted base slag with the flux facilitates the formation of the target EAF slag. These results were compared with that of mixed flux #1 (a mixture of light-burnt dolomite and limestone), which is a conventional steelmaking flux, and the possibility of replacement was evaluated. To obtain a reliable evaluation, characterization techniques like X-ray diffraction (XRD) analysis and X-ray fluorescence (XRF) spectrometry were used, and slag foam height, slag basicity, and Fe recovery were calculated.

• Journal of Service Research and Studies
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• v.13 no.1
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• pp.186-200
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• 2023

This study aims to improve the usability of the white cane, which is walking equipment that most local visually impaired people use and carry when going out, and to contribute to the prevention of safety accidents and the walking rights of visually impaired people by providing improvement and resolution measures for the problems identified. Also, this study is a study on the visually impaired, primarily targeting the 1st to 2nd degree visually impaired people, who cannot go out on their own without walking equipment such as a white cane, corresponding to 20% among approximately 250,000 blind and low vision people in the Korean population. In the study process, the concept has been developed from the user's point of view in order that the white cane becomes a real help in the walking step of the visually impaired and the improvement of usability of the white cane, the main walking equipment for the visually impaired, are done by problem identification through the Double Diamond Model of Design Thinking (Empathize → Define → Ideate → Prototype → Test (verify)). As a result of the investigation in the process of Empathy, a total of five issues was synthesized, including an increase in the proportion of the visually impaired people, an insufficient workforce situation to help all the visually impaired, an improvement and advancement of assistive devices essential for the visually impaired, problems of damage, illegal occupation, demolition, maintenance about braille blocks, making braille block paradigms for the visually impaired and for everyone. In Ideate and Prototype steps, situations derived from brainstorming were grouped and the relationship were made through the KJ method, and specific situations and major causes were organized to establish the direction of the concept. The derived solutions and major functions are defined in four categories, and representative situations requiring solutions and major functions are organized into two user scenarios. Ideas were visualized by arranging the virtual Persona and Customer Journey Map according to the situation and producing a prototype through 3D modeling. Finally, in the evaluation, the final concept derived is a device such a smart cane for guidance for the visually impaired as ① a smart cane emphasizing portability + ② compatibility with other electronic devices + ③ a product with safety and convenience.

• Korean Journal of Ecology and Environment
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• v.55 no.1
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• pp.10-18
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• 2022

This study analyzed the relationship between the community structure of benthic macroinvertebrates and habitat changes in open estuaries among the sites included in the national estuary monitoring program. The estuary survey was conducted under the "Guidelines for Investigation and Evaluation of Biometric Networks" and classified by sea area, 80 places in the East Sea, 102 places in the South Sea, and 19 places in the West Sea were investigated. In a total of 201 open estuaries, benthic macroinvertebrates were identified with 4 phyla, 9 classes, 41 orders, 139 families, 269 species and 196 species in the East Sea, 182 species in the South Sea, and 90 species in the West Sea. The highest population densities were Insecta in the East Sea, the Malacostraca in the South Sea, and the Annelida in the West Sea. Through SIMPER analysis, species contributing to the similarity of benthic macroinvertebrates communities in each sea area were identified. Some species greatly influenced the similarity of clusters. The benthic community in the East Sea was affected by the salinity, so the contribution rate of freshwater species was high. On the other hand, the benthic communities of the South and West Seas showed species compositions are influenced by the substrate composition. As results, the benthic macroinvertebrate community in Korean estuaries was impacted by salinity and substrate simultaneously, and the close relationship with geographical distance was not observed. The result of this study is expected to be used to respond to environmental changes by identifying and predicting changes in the diversity and distribution of benthic macroinvertebrates in Korea estuaries.

• Annals of Clinical Microbiology
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• v.22 no.1
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• pp.9-13
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• 2019

Background: The isolation of carbapenemase-producing Enterobacteriaceae (CPE) has become increasingly common. Continuous surveillance for these organisms is essential because their infections are closely related to outbreaks of illness and are associated with high mortality rates. The aim of this study was to develop and evaluate multiplex PCR as a means of detecting several important CPE genes simultaneously. Methods: We aimed to develop a multiplex PCR that could detect seven CPE genes simultaneously. The multiplex PCR was composed of seven primer sets for the detection of KPC, IMP, VIM, NDM-1, GES, OXA-23, and OXA-48. We designed different PCR product sizes of at least 100 bp. We evaluated the performance of this new test using 69 CPE-positive clinical isolates. Also, we confirmed the specificity to rule out false-positive reactions by using 71 carbapenem-susceptible clinical strains. Results: A total of 69 CPE clinical isolates showed positive results and were correctly identified as KPC (N=14), IMP (N=13), OXA-23 (N=12), OXA-48 (N=11), VIM (N=9), GES (N=5), and NDM (N=5) by the multiplex PCR. All 71 carbapenem-susceptible clinical isolates, including Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa, showed negative results. Conclusion: This multiplex PCR can detect seven CPE genes at a time and will be useful in clinical laboratories.

• Laboratory Medicine Online
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• v.1 no.2
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• pp.100-104
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• 2011

Background: Malaria is a problematic disease in Korea, and microscopic examination of Giemsa-stained blood smear has been used as the gold standard for its diagnosis. However, this technique is time-consuming and has low sensitivity in samples with low numbers of malarial parasites (<20 parasites/μL). Here, we evaluated the performance characteristics of the LG Advansure^TM Malaria P.f./P.v. real-time QPCR (LG life sciences, Korea). Methods: Blood samples from 173 persons who visited Korea University Ansan Hospital were evaluated. QPCR was performed in 73 malaria patients and 100 healthy subjects by using the LG Advansure Malaria P.f./P.v. real-time QPCR^R kit, and the results were compared with those of microscopy. The detection limit of this kit was determined by serial dilution of Plasmodium-infected blood with normal blood (blood not infected with Plasmodium). Results: Among the 73 patients that were microscopically confirmed to have malaria (Plasmodium vivax infection, N=70, P. falciparum infection, N=3), 69 patients were diagnosed with P. vivax infection and 3 were diagnosed with P. falciparum infection by LG Advansure^TM Malaria P.f./P.v. realtime QPCR. Both the tests indicated absence of infection in the 100 healthy subjects. The detection limit of LG Advansure^TM Malaria P.f./P.v. real-time QPCR was 0.1 parasite/μL. Conclusions: LG Advansure^TM Malaria P.f./P.v. real-time QPCRis a very sensitive and specific technique and can be used as a confirmatory test for malaria.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2335-2347
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• 2023

As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm³ to 4.14 g/cm³, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm³, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm³ with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.

• Journal of the Korean Society of International Agriculture
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• v.31 no.4
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• pp.428-436
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• 2019

As the main objective of rice breeding programs, rice eating quality is one of critical factors directly determining the market price and the consumer preference. However, the genetic complexity of eating quality and the difficulty in accurate evaluation often constrain improvement of the eating quality in rice breeding programs. In addition, given that the rice eating quality of current cultivars has already reached some high-level, diversifying of genetic resources are demanded more than ever to improve the rice eating quality. In this study, we developed a recombinant inbred lines (RILs) population derive from Wandoaengmi6, a japonica-type Korean weedy rice with high eating quality and a high degree of glossiness of cooked rice. Year-to-year correlations between the traits in three years were shown normal distribution for major agronomic traits and physicochemical characteristics. After evaluating tested traits related to eating quality procedure, a total of ten lines were ultimately selected from the population. Increasement of the taste of cooked rice (TA) and the overall eating quality (OE) were confirmed in the selected lines, which are caused by alleles derived from Wandoaengmi6 without any linkage drag. These results indicate that the utility of wide genomic resources in Korean landrace could be of application in various rice breeding programs and countermeasure to contribute to properly response to climate change.

• Korean Journal of Plant Resources
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• v.36 no.5
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• pp.435-445
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• 2023

The aim of this study was to explore the effects of vinegar extract from seed of common buckwheat (Fagopyrum esculentum Moench) and seed of tartary buckwheat (F. tataricum Gaertner) on acute ethanol-induced hangover in Sprague-Dawley rats. Vinegar extract from buckwheat is rich choline, quercetin and its glycoside, rutin known as flavonoid antioxidants. The test extract containing buckwheat was proven to alleviate hangovers through a significant reduction in the concentration of alcohol and acetaldehyde in the context of an alcohol-induced hangover model. Hepatic alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) activities were significantly higher in buckwheat vinegar-treated rats than in ethanol-treated rats. Moreover, tartary buckwheat vinegar upregulated antioxidant enzyme such as superoxide dismutase and Catalase activities in liver tissues. These results suggest that buckwheat vinegar extract could alleviate ethanol-induced hangover symptoms by elevating activities related to hepatic ethanol-metabolizing enzymes against ethanol induced metabolites, and in particular, tartary buckwheat should be further developed to be a novel anti-hangover material.