• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.206-213
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• 2013

Glass eels (Anguilla japonica) are caught in the west coast of Korea on their migratory route from the breeding grounds in the Mariana Trench along the North Equatorial Current and the Kuroshio Current. To identify the food source of natural glass eels, we analyzed the stable C and N isotopes of glass eels caught in April 2012 and investigated possible food sources in the survey area. In particular, with respect to the stable C and N isotopes of particulate organic matter, we extended the surveying area to the northern parts of East China Sea as well as the west coast of Korea. The stable C and N isotope ratios of the glass eels caught in the west coast were found to be $-20.7{\pm}0.1$‰ and $5.0{\pm}0.2$‰, respectively. The stable C and N isotope ratios of the particulate organic matter in the west coast of Korea, in which the glass eels are assumed to eat the particulate organic matter as food source, were estimated to be $-24.0{\pm}0.3$‰ and $2.8{\pm}0.4$‰, respectively. Similar data were obtained from the northern part of the East China Sea, $-24.5{\pm}0.5$‰ and $0.8{\pm}0.3$‰. The stable isotope ratios showed values differing from the stepwise increasing rates up the food web in natural aquatic ecosystem, showing that particulate organic matter in the west coast of Korea and East China Sea was not served as the glass eels food source. This result suggested that the glass eels caught in the west coast might not assimilate nutrition from the marine environment during long migration.

• Asian Journal of Atmospheric Environment
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• v.7 no.2
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• pp.120-128
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• 2013

The concentration and composition of particulate matter (PM) in the atmosphere can directly reflect the environmental pollution. The atmospheric pollution in some Cameroonian cities is increasing with the industrial development and urbanization. Air pollution is inherently complex, containing PM of varied size and composition. This PM exists as a dynamic cloud interacting with sunlight and is modified by the meteorology. The reflectometer and the EDXRF spectrometry are applied to determine the concentration of some specific elements at four sites in the city of Yaound$\acute{e}$. The particular aim of the present work is to put in place data base on air pollution in urban area and elaborate regulations on the emissions issued to industrial and vehicle activities. This study provides an overview of the concentration of black carbon and some specific elements in the air, which have impacts on human health. The measurement was done by distinguishing the size of particle. So that, the particle with aerodynamic diameter between $2.5-10{\mu}m$ (so-called coarse particle) and aerodynamic diameter < $2.5{\mu}m$ (so-called fine particle) were considered to obtain more information about levels of the inhalable fraction of the location. The results obtained in four locations of the city of Yaound$\acute{e}$ show that the black carbon concentration is very considerable, the element sulfur is a major pollutant and the concentration of fine particle is very greater. The results obtained of fine and coarse filters range from $5-17{\mu}g/m^3$ and $10-18{\mu}g/m^3$ for the black carbon. S, Cu, Zn, Pb, Cd, As, Se and Hg are the specific findings of this work. The pollutants with a greater concentration are S, Pb, and Zn. These later seem to be non-uniformly, non-regular in some location and high compared to other countries. This work allows us to make a potential relation between pollutants and emission sources. In this framework, some suggestions have been proposed to reduce emissions for an improvement of the air quality in the environment and thus, the one of the city of Yaound$\acute{e}$.

• Journal of Wetlands Research
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• v.17 no.3
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• pp.283-292
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• 2015

The total global emission of $CO_2$ from soils is recognized as one of the largest fluxes in the global carbon cycle. Especially it is necessary to quantify the amount of $CO_2$ emitted by the organic material decomposition processes of microorganisms in the soil, because it becomes one of a factor for determining the carbon stocks in the soil. This study was conducted to estimate the impact of the Korean water deer(Hydropotes inermis)' feces to the soil organic matter. Also, effects of Korean water deer' feces on $CO_2$ emissions of soil and land use pattern dependent $CO_2$ flux quantification are studied. The organic materials in the Korean water deer' feces significantly changed organic matter content of soil and influenced the activity of soil microorganisms, both changing of respiration of the soil and physical chemical components in soil. In particular, C/N ratio and the $CO_2$ flux of soil of four regions (Rice paddy, Fallow ground, Salix koreensis community, Phragmites australis community) showed a statistically highly significant correlation (P<0.01) with the presence or absence of feces. $CO_2$ flux of soil affected by the feces was 2-20 times higher than the soil unaffected by the feces. This study has great significance to quantify the extent of the material circulation and its impact to the terrestrial ecosystem and soil zone throughout Korean water deer' feces. Feces of wildlife can affect soil and soil material circulation.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.753-767
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• 2013

Soil contamination has continuously increased worldwide, thus the remediation for the contaminated soils has risen steadily. However, the consideration of ecological safety for the remediated soils and their agricultural uses has been very limited. Therefore, this study was to investigate the influences of selected environmentally-friendly agricultural materials, organic by-product fertilizer (OF), charcoal (CC), and biochar (BC), as soil conditioners for improving poor chemical properties of fuel-oil removed soil by land farming technique. Two different remediated soils, remediated soil A (RSA) and remediated soil B (RSB), were selected. Soil texture of both RSA and RSB was sandy loam. The chemical properties of RSA and RSB were as follows: soil pHs of 8.5 and 8.7, soil organic matter contents of 7.4 and 5.5g $kg^{-1}$, total nitrogen contents of 0.26 and 0.10g $kg^{-1}$, available phosphorus concentrations of 7.2 and 4.4mg $kg^{-1}$, and exchangeable calcium concentrations of 14.8 and $11.7cmol_c$ $kg^{-1}$, respectively. Results of the properties were not reached for the optimal values for cultivating crops that were recommended by National Academy of Agricultural Science at Rural Development Administration in Korea. However, after applying OF, CC, and BC, the chemical properties of soils were selectively improved, which were that soil organic matter content and available phosphorus concentration increased, whereas the soil pH were not changed. In particular, the chemical properties were positively changed more with the application of 5.0% biochar. Thus, continuous management of the remediated soils with applying the eco-friendly agricultural materials can improve the quality of reme-diated soils.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.119-124
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• 2015

In this study, we sought to evaluate the growth characteristics and seed productivities of domestic tall fescue that were cultivated with differing combinations of drill widths and nitrogen-application rates in early spring; the examination was conducted at the National Institute of Animal Science, RDA, from 2013 to 2014. The main plots were three widths of 15 cm, 30 cm, and 45 cm, and the subplots were subject to nitrogen-application rates in early spring of 45 kg/ha, 90 kg/ha, 135 kg/ha, and 180 kg/ha. The growth and development characteristics did not vary by treatment in terms of drill width and early-spring nitrogen application. Tall fescue Purumi showed a stable seed productivity of two tons or greater when the drill width was set at 15 cm and 90 kg/ha of nitrogen was applied in early spring. The narrower the drill width, the greater the numbers of both the ears and seeds, while the length of the ear was longer when the drill width was wider. Regarding the influence of the drill width and early-spring nitrogen application on the productivity of seed-producing straw, the dry matter productivity was higher when the drill width was narrower; however, no particular trend was observed with respect to different amounts of fertilizer. The average production amount of the first round of straw after seed gathering was 6,920 kg/ha. The second round produced an average 8,134 kg/ha of dry matter.

• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.17-31
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• 1982

A physician assumes toward his patient the obligation to use such reasonable care and skill as is commonly possessed and exercised by physicians in the same general line of practice in the same or similar localities and to use his best judgment at the times. Medical disputes between physicians and patients are, ever more increased in these days as human body, happens to cause a variety of changes in body unlike the function of machine. Such increased trends of medical disputes became a problem in common across the word under the influence of affluent living standard, high consciousness of life value and right by today's people. The aim of this dissertation is oriented to forming a physician's responsibilities in medicalcare accidents arising between physicians and patients. A general physician, for example, has not been negligent merely because, a specialist might have treated the patient with greater skill and knowledge. However, the fact that a physician may have acted to the best of his ability will not avoid legal problems for damages resulting from substandard treatment, that is the degree of care and skill which is to be expected of the ordinary practitioner in his field of practice. The duty of a physician who is, or holds himself out to be, a specialist is greater in the field of his specialty than one who is a general physician. A patient's consent to routine medical procedures is implied from the fact that patient comes to the physician with a medical problem and voluntarily submits to the procedures. For the more serious medical procedures and for major operations, however, it is preferable for the physician to have the patient's consent in writing, to facilitate proof of the consent in the event of a dispute or litigation. Suppose that mistakes on the part of physicians are likely to be blamed in all cases of malpractice. Then it will create a sort of shrinkage in activities of medical treatment. There should be some limitation on excessive application of 'The thing speaks for itself' on mistakes by physicians and availablity of cause and effect. It is a matter of complicity as well as a matter of importance to draw a definite boundary on responsibilities of physician. A series of further research on this particular aspect is strongly urged.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.4
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• pp.318-324
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• 2017

Lime bordeaux mixture (LBM) and lime sulfur mixture (LSM) are representative environmental friendly organic materials for prevention of insect pests in South Korea. Recently, those have been widely used as an alternative for chemical pesticides in eco-friendly farms. However, South Korea has not established even recommendation of LBM and LSM considering the stability of heavy metals in soil. The aim of this study was to evaluate the accumulation of hazardous heavy metals in soil and plant with long-term application of LBM and LSM. Firstly, we investigated the amount of LBM and LSM used per year in several eco-friendly farms to determine a standard application rate of both materials. The pepper plant was grown on the pot in greenhouse for 14 weeks. Both materials were applied at 0, 1, 3, and 9 times of standard application rates (2.56 and $1.28L\;ha^{-1}$ of LBM and LSM per year, respectively). Dry matter yield of pepper and heavy metals (As, Cd, Cu, Hg, Ni, Pb, and Zn) concentration in soil and pepper plant were measured after 14 weeks. Yield of pepper plant did not significantly chang with up to application rate of 1 times, thereafter it markedly decreased with more than 3 times. With increasing LBM and LSM application, the concentration of Cu and Zn in soil significantly increased. Especially, Zn concentration in pepper significantly increased with increasing application rates of both materials. This might resulted in significant decrease in dry matter yield of pepper. The concentrations of those heavy metals in soil did not exceed safety levels ($150mg\;kg^{-1}$ for Cu and $300mg\;kg^{-1}$ for Zn) established by the Korean Soil Environmental Conservation Act as well as concentration of heavy metals in pepper plant by Korean Ministry of Food and Drug Safety. However, particular attention should be paid for heavy metal safety and crop productivity when using LBM and LSM in the organic farm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.597-606
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• 2016

This is descriptive research to understand the constipation rate of elementary school students due to their differences in cognition of their eating habits, hours of exercise/physical activity, stress, and school restroom environment in accordance with the matter of constipation, as well as the factors related to the constipation rate. A total of 741 students (grade3-6) from six elementary schools in Jeollanam-do were targeted; the survey was conducted from April 30th to May 12th, 2014. The frequency, percentage, ${\chi}^2$ test, independent t-test, and bivariate logistic regression analysis were conducted. The constipation rate was 23.9%, and there were factors related to the constipation rate, such as restroom preference, matter of defecation during breaks, number of meals per day, number of breakfasts skipped, size of the meal, hours of institute class, hours of internet use, stress, and cognition of school restroom environment. In particular, students with 'high' stress had a 5.44 times higher rate of constipation than students with 'low' stress. As subjective symptoms are limited in diagnosing constipation, a detailed medical examination and physical checkup should be included in the process of understanding the constipation rate, as well as in education and management to prevent elementary school students from having constipation.

• Journal of the Korean earth science society
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• v.32 no.4
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• pp.422-434
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• 2011

The purpose of this research is to investigate the actual conditions of primary school science teaching and ways to improve it. In elementary science teaching, teachers themselves tend to have science misconceptions and insufficient science content knowledge. Experienced teachers argued that it could be hard for elementary teachers with lack of science content knowledge to provide their students with meaningful learning experiences of science. Based on the general characteristics of elementary teaching and the awareness of elementary teachers' insufficient science content knowledge, we explored the real situation of the elementary science classroom. We conducted open-ended interviews with teachers and focus group discussions on a regular basis to analyze and compare classes of five primary school teachers. Data analysis focused on why elementary students avoid science classes in upper grades of elementary school and why elementary science classes always need hands-on activities. We also discussed ways to turn hands-on investigation into minds-on investigation by connecting it to important ideas in science. Based on the results, we suggested ways to improve inservice teacher training such as designing supplementary in-service training focused on content knowledge for primary school teachers, setting up professional exchange or collaboration between primary and secondary teachers, and introducing subject-specialized teachers for the fifth and sixth graders of primary school. In particular, considering elementary teachers' insufficient science content knowledge, employing science subject matter specialists in the elementary school could be a useful strategy.

• Journal of The Korean Association For Science Education
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• v.40 no.4
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• pp.415-427
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• 2020

This study aims to understand science education conducted in North Korea by analyzing the PCK components shown in two science teacher's guidebooks: (1) Guidebook for 1^st grade elementary school and (2) Guidebook for 1^st grade middle school. These were published after 2013, when "the first 12-year Universal Compulsory Curriculum" was implemented in North Korea. The analysis shows that both elementary and middle school guidebooks had the highest percentage of content in "Knowledge of Subject Matter", followed by "Knowledge of Instructional Strategies in Science" and "Knowledge of Science Curriculum". On the other hand, "Knowledge of Assessment in Science" and "Knowledge of Students" were significantly low in content. Within the "Knowledge of Subject Matter", both elementary and middle schools had the highest proportion of content in "Concepts and Theories", along with "Experiments and Inquiries" that was also significantly higher than other PCK components. Science teacher's guidebooks in North Korea advocates constructivist teaching style by using "discussions" as the main activity when conveying scientific concepts and theories to students or conducting scientific inquiry classes. Furthermore, "Knowledge of Instructional Strategies in Science" was mainly focused on guiding the "Instruction sequence and method" from the "Topic-specific Strategies", while only a small part of the "Subject-specific Strategies" was being presented. Also, Science teacher's guide books in North Korea included only a few theoretical elements of science education in both the general outline and the particular sections of guidebooks. "Knowledge of Science Curriculum" was mainly composed of "Lesson Objectives" with some inclusion of "Vertical Articulation" and "Horizontal Articulation". "Knowledge of Assessment in Science" and "Knowledge of Students" accounted for a small portion compared to the science teacher's guidebooks in South Korea.