• The Korean Journal of Ecology
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• v.27 no.6 s.122
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• pp.375-381
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• 2004

We investigate the biological treatment of processed-leachate from SUDOKWON landfill site in Korea by the reed (Phragmites australis)-bed with a continuous flow system. The reed individuals showing superior growth in processed-leachate experiment were selected among the reeds of thirteen natural habitats by means of the comparisons between the removal rates of nutrient salts, eco-physiological responses and growth. The reed-beds (combination of the reed individuals showing superior growth with helper microorganisms) were continuously supplied with processed-leachate. We monitored the effluents that passing through the reed-beds during the experiment period. After five weeks, analysis results of effluent from each reed-bed were as follows; chromaticity, total nitrogen, total phosphorus, biological oxygen demand, chemical oxygen demand, total dissolved solid and salinity decreased $29.5{\sim}36.9\%,\;49.4{\sim}67.2\%,\;42.1{\sim}94.6\%,\;74.5{\sim}88.8\%,\;15.6{\sim}20.8\%,\;17.5{\sim}35.4\%\;and\;15.3{\sim}34.7\%$, respectively. These results represented the substantial improvement of water-quality after passing through reed-bed in a continuous flow system.

• Journal of Ecology and Environment
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• v.30 no.2
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• pp.187-193
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• 2007

Higher plants can be categorized as C3, C4 or CAM according to their photosynthetic pathways, and some succulent plants are known to shift their patterns of photosynthesis from C3 to CAM in response to environmental stresses such as salt treatment or water deficiency. To investigate fundamental photosynthetic patterns and the induction of pattern shifts (C3, CAM, C3-CAM etc.) as a result of environmental stresses, we measured the water content, diurnal changes in pH, net $CO_2$ exchange, transpiration rate, total ionic contents, and osmolality of Kalancoe daigremontiana, Sedum kamschaticum and Sedum sarmentosum which belong to Crassulaceae known as representative CAM plant, after 10 days of drought treatment. S. kamschaticum and S. sarmentosum did not show a significant difference in diurnal pH variation in the treatment and control conditions. However, the pH of drought-treated Kalancoe was low at night and high in the daytime, with a pH value between 4 and 5. Typical CAM plants display a net $CO_2$ exchange that increases at night and decreases in the daytime. Kalancoe displayed the predicted pattern. However, S. kamschaticum and S. sarmentosum showed a photosynthetic pattern more typical of C3 plants, and did not show changes in photosynthetic pattern under drought stress. Kalancoe also showed a transpiration rate typical for CAM pho-tosynthesis, whereas the transpiration rates of S. kamschaticum and S. sarmentosum were in the typical range for C3 photosynthesis. Kalancoe had high total ionic contents during the night, which decreased somewhat during the daytime, whereas S. kamschaticum and S. sarmentosum displayed the opposite pattern. This result is similar to the diurnal patterns of changes in pH in the three plant species, which suggests a relationship between pH and ionic contents. S. sarmentosum showed lower osmolality under drought stress than in the control condition, whereas the osmolality of Kalancoe and S. kamschaticum did not differ between conditions. S. sarmentosum may have maintained internal water content by lowering its osmolality and raising its total ionic contents. In conclusion, Kalancoe displayed the characteristic responses of a typical CAM plant, whereas S. kamschaticum and S. sarmentosum displayed aspects of the C3 photosynthetic pattern under drought conditions. These results suggest that S. kamschaticum and S. sarmentosum (Crassulacea) in Korea overcome drought stress by increasing solute and ionic contents internally rather than changing their photosynthetic pattern from C3 to CAM under drought stress.

• Journal of Climate Change Research
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• v.7 no.1
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• pp.9-17
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• 2016

Climate change affects plant responses on physiological characteristics and growth, and Pinus densiflora, one of the major tree species in Korea, are expected to be particularly vulnerable to rising temperature and increased precipitation. This study was conducted to investigate the effects of an open-field warming and precipitation manipulation on physiological characteristics and growth of P. densiflora seedlings. Seedlings of 2-year-old P. densiflora were planted in April, 2013, in open-field nursery located at Korea University. The air temperature of warmed plots had been set to be $3^{\circ}C$ higher than the control plots using infrared lamps. Precipitation was manipulated to be 30% lower or higher than the control, using transparent panels and drip irrigation. Net photosynthetic rate, total chlorophyll content, seedling height, root collar diameter and biomass were measured from April, 2014 to April, 2015. The increase in new shoot biomass from warming was statistically significant, with the biomass in warmed plots about 2-fold higher than in the control plots in 2014 and 2015. This result might be related to advanced bud burst and increased occurrence of abnormal new shoots in warmed plots. Meanwhile, the results of net photosynthetic rate, total chlorophyll content, seedling height, root collar diameter and total biomass from warming and precipitation manipulation were not statistically significant, but tendencies of lower net photosynthetic rate and higher seedling height and biomass in warmed plots compared to the control were shown. Such might be speculated as results of the extended growth period. When root to shoot (R/S) ratio was calculated from the biomass data obtained in April 2014 and April 2015, increased R/S ratio was observed regardless of the treatments applied. Drought tolerance of P. densiflora and particularly low annual precipitation observed in 2014 were suggested as the possible reasons.

• Journal of Korean Foot and Ankle Society
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• v.25 no.3
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• pp.111-116
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• 2021

Purpose: Variations in the preferred conservative and operative treatment methods for ankle arthritis may be observed in the practice of orthopedic surgeons. This study is based on the Korean Foot and Ankle Society (KFAS) member survey and aims to report the current trend and changes in the management of ankle arthritis over the last few decades. Materials and Methods: A web-based questionnaire containing 24 questions was sent to all KFAS members in July 2021. The questions were mainly related to the preferred techniques and clinical experience in osteotomy, arthrodesis, and total ankle arthroplasty (TAA) for patients with ankle arthritis. Results: Sixty-three out of 550 surgeons (11.5%) responded to the survey. The responses to 6 out of the total of 24 questions (25.0%) achieved the levels needed to reflect a tendency. Answers that showed a tendency were related to the following: a surgical approach for arthrodesis (anterior approach), use of auto-bone graft for arthrodesis (iliac bone), a nonunion rate of more than 10% following arthrodesis, main reason related to unsatisfactory results after arthrodesis (nonunion or delayed union), the main reason to change total ankle prosthesis (unstable supply of prosthesis), the unusualness of revision TAA and conversion of fusion to TAA. Diversity was found in several aspects of treatment (degree of experience and satisfaction in supramalleolar osteotomy, fixation method for arthrodesis, preferred TAA prosthesis and longevity, degree of experinece, annual number of TAA operation. Conclusion: This study proposes updated information with regard to the current trends in the management of ankle arthritis in Korea. Both consensus and variations in the approach to patients with ankle arthritis were identified through this survey. With an increasing preference for TAA, the need for the development of a prosthesis optimized for Koreans and a stable supply of prostheses were the suggestions made by the study.

• Korean Journal of Exercise Nutrition
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• v.24 no.2
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• pp.30-37
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• 2020

[Purpose] The present study investigated the effect of endurance exercise with blood flow restriction (BFR) performed at either 25% maximal oxygen uptake (${\dot{V}}O_2$ max) or 40% ${\dot{V}}O_2$ max) on muscle oxygenation, energy metabolism, and endocrine responses. [Methods] Ten males were recruited in the present study. The subjects performed three trials: (1) endurance exercise at 40% ${\dot{V}}O_2$ max without BFR (NBFR40), (2) endurance exercise at 25% ${\dot{V}}O_2$ max with BFR (BFR25), and (3) endurance exercise at 40% ${\dot{V}}O_2$ max with BFR (BFR40). The exercises were performed for 15 min during which the pedaling frequency was set at 70 rpm. In BFR25 and BFR40, 2 min of pressure phase (equivalent to 160 mmHg) followed by 1 min of release phase were repeated five times (5 × 3 min) throughout 15 minutes of exercise. During exercise, muscle oxygenation and concentration of respiratory gases were measured. The blood samples were collected before exercise, immediately after 15 min of exercise, and at 15, 30, and 60 minutes after completion of exercise. [Results] Deoxygenated hemoglobin (deoxy-Hb) level during exercise was significantly higher with BFR25 and BFR40 than that with NBFR40. BFR40 showed significantly higher total-hemoglobin (total-Hb) than NBFR40 during 2 min of pressure phase. Moreover, exercise-induced lactate elevation and pH reduction were significantly augmented in BFR40, with concomitant increase in serum cortisol concentration after exercise. Carbohydrate (CHO) oxidation was significantly higher with BFR40 than that with NBFR40 and BFR25, whereas fat oxidation was lower with BFR40. [Conclusion] Deoxy-Hb and total Hb levels were significantly increased during 15 min of pedaling exercise in BFR25 and BFR40, indicating augmented local hypoxia and blood volume (blood perfusion) in the muscle. Moreover, low-and moderate-intensity exercise with BFR facilitated CHO oxidation.

• Korean Journal of Environmental Biology
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• v.26 no.4
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• pp.271-278
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• 2008

The differences of several kinds of physiological responses between Commelina communis (C$_3$ plant) and Sedum sarmentosum (CAM plant: Crassulacean Acid metabolism) when both plants were exposed to water stress for 3 weeks were investigated. In case of Commelina it was shown a clear loss of water to 12% in three weeks, but no changes were observed in Sedum. Total chlorophyll content was also reduced to 57% in Commelina but not clear changes of chlorophyll content in Sedum. were observed for three weeks. In chlorophyll fluorescence experiments Fv/Fm ratios were reduced to 19% in Commelina, but no changes were observed in Sedum. There were very sensitive responses according to the different KCl concentrations and the stomatal aperture of epidermal strips was 12.8 ${\mu}m$ at 200 mM KCl in Commelina, but less than 3 ${\mu}m$ was observed at the same KCl concentration in Sedum. In addition, there were no chloroplasts in guard cells of Sedum, but most plants had chloroplasts including Commelina. From the above results, the ability of water stress resistance in Sedum. could be come from slow physiological metabolism including growth and less loss of water through unique stomatal characteristics.

• Culinary science and hospitality research
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• v.22 no.3
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• pp.121-138
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• 2016

This study is intended to present effective career guidance and direction by identifying the various factors involved in the career preparation behavior for the improvement of the employment rate of culinary and foodservice management major field students. This study was established on the hypothesis of a structural relationship that career decision-making self-efficacy develops career maturity and career preparation behavior on the basis of social cognitive career theory, which was verified through empirical analysis. Out of 450 survey responses from by Culinary and Foodservice Management Major Students, a total of 302 questionnaires were used for the final analysis due to missing values and biased responses(response rate: 83.6%). Collected data were identified using SPSS 16.0 and AMOS 5.0. A higher-order factor model was employed (High-order model) before a confirmatory factor analysis, and this study examined its reliability and validity analysis for hypothesis testing. Career decision-making self-efficacy had positive effects on career maturity(t=6.86, p<0.001) and career preparation behavior(t=3.83, p<0.001), and career maturity had positive effects on career preparation behavior (t=2.79, p<0.01). As a result, all hypotheses were accepted. These results confirmed that strengthening students' faith in themselves with competencies is core competencies with career-related issue can be the driving force that can enable students to develop into mature professionals. Therefore, this study suggests an awareness of the importance of career decision-making self efficacy and proposes a need for a systematic and integrated career counseling program that can improve it.

• Journal of Korean Academy of Nursing Administration
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• v.4 no.2
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• pp.289-306
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• 1998

For continuous development of professional nursing to the powerful professional organization, it is essential that the public understand and help nursing. This research was done to identify the image of nurses and factors that determine that image. The study subjects were 97 admitted patients 95 family members of patients who were admitted to a university hospital and a general hospital in Seoul and 164 parents of stutents in elemantary, middle, high schools in Seoul. The total numbers of subjects was 356. The researcher collected the data from April 13.1998 to April 20.1998. The Research tool was developed by the researcher following a literature review. Cronbach ${\alpha}$ for the tool of the image of nurses was 0.9397 and Cronbach a for the tool for determinants of the image was 0.8764. The obtained data were processed by SPSS (Statistical Package for Social Science) and the results are as follows : 1. The mean score for the image of nurses was 90.40${\pm}$15.15(range 47${\sim}$138) indicating a positive response. 2. Analysis of the image of nurses : Four factors were identified traditional. social. professional and personal image. The mean score for traditional image was 3.27. the second highest score. and for social image. 2.95. the lowest score. The mean score for professional image score was 3.48. the highest score. and for personal image, 3.20. a lower score. 3. The image of nurses according to respondents There were significant differences for traditional. social, professional. personal factors between subject groups. A more positive responses was found in the patients and patient' families as a compared to the students' parents. 4. Image of nurses related general characteristics : There was a significant difference for age and school graduation. More negative responses were found in the 31${\sim}$40 years old age group and in the higher educated group. 5. Image of nurses related to experience of nurses The respondents showed a more negative image when their experience related to nurses through the mass media, as a compared to the experiences of having talked with patient who had been admitted to hospital. For the social image factor. a more negative attitude was revealed for those who had the experience of patient who had been admitted to hospital as compared to other factors. 6. Determinants of image of nurses : There were three factors that were named subjective. administrative and media . The mean for the subjective factor score was 3.85. the highest score of the three factors. The mean for the administrative factor score was 3.53. And the mean for the media factor score was 3.27. 7. Determinants of image of nurses according to respondents group : There were no significant differences(F= 1.95, P= .14) Consequently the result showed a low social image of nurses. So. nurses must work to improve the social image of nurses through scientific approaches and by monitoring the mass media for correct descriptions of nurses. Also. it is necessary that excellent education for service and politeness be continually provided in order to positively effect the personal image field. It is also importent to raise the expectations of the recipients of nursing care by having a strategy for the determinants of the image of nurses that allows nurses to personnally develop professionally.

• Journal of Music and Human Behavior
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• v.13 no.2
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• pp.1-16
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• 2016

The purpose of this study was to examine how primary school teachers use music for classroom teaching and management and how they perceive the effects of using music in their classroom. A total of 190 questionnaires were collected from primary school teachers and 119 responses were analyzed after excluding four responses from music teachers who are not in charge of a classroom. The results demonstrated that a greater number of respondents reported the use of music for classroom teaching than for classroom management. With regard to music use for classroom management, teachers most often attempted to enhance positive emotions of their students by playing children's songs. For classroom teaching, music was frequently used to increase students' motivation for learning. Also, while first through third grade teachers tended to use music frequently for both classroom teaching and management, fourth through sixth grade teachers mainly used music for teaching. Although most of the respondents perceived the positive influence of music on their children, they reported difficulties in using music in their classrooms. Respondents indicated the needs for music-related training or provision of materials to support teachers for effectively using music. Future studies are needed to develop music resource materials that could be readily utilized by teachers in a variety of contexts in primary school.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.128-133
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• 2017

To determine the optimum water temperature (a temperature which minimizes metabolic activities and stress in fish) for long distance transportation of red-spotted grouper (Epinephelus akaara), by evaluating the behavior, survival and physiological and hematological responses to variable water temperature conditions (9, 12, 15, 18 and $21^{\circ}C$) for 48 hours. Fish exposed to $9^{\circ}C$ died at 48 hours exposure, but those exposed to 12, 15, 18 and $21^{\circ}C$ treatment groups all survived. Fish in the 15, 18 and $21^{\circ}C$ exposure groups exhibited normal swimming, while those exposed to $12^{\circ}C$ were observed to be stationary at the bottom of the tank. The plasma cortisol and glucose concentration were higher in fish exposed to $12^{\circ}C$ than at other temperature conditions. The fish in the 12 and $15^{\circ}C$ groups had significantly higher hematocrit (Ht) and hemoglobin (Hb) than those in the 18 and $21^{\circ}C$ groups (P<0.05). Levels of aspartate aminotransferase (AST), $NH_3$ and osmolality showed a pattern similar to the levels of plasma cortisol, while alanine aminotransferase (ALT) and total protein did not significantly vary among the experimental groups. These results indicate that the optimum water temperature for long distance transportation of the red-spotted grouper is $15^{\circ}C$.