• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.821-827
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• 2014

An isotope dilution liquid chromatography tandem mass spectrometry (ID LC-MS/MS) method has been developed and applied to the determination of arsenobetaine (AsB, ${(CH_3)_3}^+AsCH_2COO^-$) from oyster candidate certified reference material (CRM). The exact matching isotope dilution approach was adopted for accurate determination of AsB using $^{13}C_2$-labeled AsB as an internal standard. Efficiencies of different AsB extraction methods were evaluated using a codfish reference material and a simple sonication method was selected as the method of choice for the certification of the oyster candidate CRM. The hydrophilic interaction liquid chromatography (HILIC) combined with electrospray ionization tandem mass spectrometry (ESI/MS/MS) in selected reaction monitoring (SRM) mode was optimized for adequate chromatographic retention and robust quantification of AsB from codfish and oyster samples. By analyzing 12 subsamples taken from each 12 bottles systematically selected from the whole oyster CRM batch, the certified value of AsB was determined as $6.60mg{\cdot}kg^{-1}{\pm}0.31mg{\cdot}kg^{-1}$ and it showed excellent between-bottle homogeneity of less than 0.42%, which is represented by relative standard deviation of 12 bottles from the CRM batch. The major source of uncertainty was the certified value of the AsB standard solution.

• Journal of Environmental Health Sciences
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• v.37 no.2
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• pp.113-123
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• 2011

Objectives: Industrial development in Korea results in a rapid increase in the number of chemicals, some of which may be responsible for toxicity to aquatic ecosystems. In addition, the types of hazardous chemicals included in industrial effluents have gradually increased. Therefore, chemical analysis alone is not enough to assess ecological effects of toxic chemicals in wastewater. Methods: In response to new regulations as whole effluent toxicity (WET) tests for effluent discharge of 15 publicly owned treatment works (POTWs) and 25 industrial effluent treatment plants in Gyeonggi-do, which will be effective from 2011, a necessity of studies emerges that investigates toxicity levels. Results: In case of the public treatment plants, none of them had exceeded the criteria for ecotoxicity. As for individual wastewater discharge facilities, on the other hand, two types were found to exceed the criteria: pulp and paper manufacturing facilities and pharmaceutical manufacturing facilities. For the pulp and paper manufacturing facilities, monitoring results could not help determine the exact toxicant identification. However, Daphnia magna inhibition effect or death was found to leave white plums, suggesting that suspended solids treated and the polymer used in coagulant dose. In case of pharmaceutical manufacturing facilities, the general water quality parameters cannot affect Daphia magna. However, conductivity and salinity can have an effect to be 14,000 ${\mu}s/cm$, 8.1‰ by salts, respectively. Toxicity Identification Evaluation (TIE) and Toxicity Reduction Evaluation (TRE) procedures results appeared to be effective for identifying toxic compounds in $Cl^{-}$ and $SO_4^{2-}$. Conclusions: It is necessary to develop control measures for water treatment chemicals and salts used for processes such as coagulation in individual wastewater discharge facilities in order to achieve the goal to protect aquatic ecosystems in public waters.

• Journal of Korean Elementary Science Education
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• v.23 no.4
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• pp.318-325
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• 2004

The purpose of this study is to improve the experiment of dihydrogen production which was newly added to the 7th curriculum of the elementary science education. For this study, the teachers who had taught 6th grade students were asked about the difficulties they ever had in the dihydrogen production experiment by questionnaire. And the contents of the science textbook and teachers' guide book were analyzed. According to this investigation, the following controversial points were found. First, they didn't have exact explanations about the concentration of hydrochloric acid and the quantity of hydrochloric acid and magnesium in the science textbook and teachers' guide book. Second, the experiment which can show well the nature of dihydrogen was not included because of the safety problem. So this paper presents the ideal condition for the production of dihydrogen and an experimental method to show the nature of dihydrogen. The most ideal condition of dihydrogen production includes 40 mL of 2 molarity hydrochloric acid and 1 g of magnesium. It took 5' 42＆apos; on average to gather two bottles (250 mL) of dihydrogen. In this condition it was possible to reduce the risk of accidents and to economize the materials. This paper proposes the experiment of dihydrogen explosion with a test tube and a film box which is not included in the 7th scince textbook. If teachers show the experiment of dihydrogen explosion with a test tube or film box to students at a class, it will be more interesting for students. And they will be able to help students to understand that dihydrogen can be gathered.

• Journal of Korean Foot and Ankle Society
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• v.9 no.1
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• pp.99-104
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• 2005

Purpose: The purpose of this study was to investigate usefulness of locking compression plate (LCP) as an open reduction technique by evaluating clinical results obtained from the patients with lateral malleolar fracture treated by internal fixation using LCP after open reduction. Materials and Methods: Among the patients with lateral malleolar fracture, the 28 patients who were treated by internal fixation using Locking compression plate after an open reduction and were able to be followed up for more than 6 months were included in this study. Final postoperative evaluation was done based on the Meyer's clinical and radiologic evaluation system. Results: All cases achieved anatomical reduction and fixation of the reduction postoperatively. 28 minutes were taken meaningly from the incision to the fixation of LCP plate after the anatomical reduction. Everage bony union time was 8.2 weaks, and the result was excellent in 23 cases (82%), good in 5 cases (17%) and poor result was abscent according to the criteria of Meyer et al. One case of post traumatic arthritis and one case of superficial infection on the operation site were found, but non-union, delayed union and malunion were not occurred. Conclusion: The internal fixation after open reduction using LCP is an effective treatment method in treating lateral malleolar fracture of the ankle since it offers advantages including easy application and a greater stability due to its capability of maintaining exact anatomical reduction even though the screw does not penetrate the medial cortex of fibular to add the stability and rigidity of the fixation.

• The Journal of Korean Academic Society of Nursing Education
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• v.19 no.4
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• pp.580-593
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• 2013

Purpose: This study was conducted to develop and implement an educational program for cultural competence in nursing for nursing students, and to evaluate its effects on transcultural self-efficacy, intercultural communication competence, and state anxiety. Methods: A nonequivalent control group pretest-posttest design was used with an experimental group (n=22) and a control group (n=27). Outcome variables were measured by transcultural self-efficacy, intercultural communication competence, and state anxiety before and after the program. The experimental group participated in an educational course for cultural competence in nursing for 14 weeks while the control group did not participate in any course. Chi-square test, Fisher's exact probability test, t-test, MANCOVA, and ANCOVA were performed to analyze the data. Results: The experimental group showed significantly higher posttest scores in the transcultural self-efficacy score (F=19.76, p<.001, partial ${\eta}^2=.34$, observed power .99) and the intercultural communication competence score (F=17.56, p<.001, partial ${\eta}^2=.32$, observed power .98) than that of the control group. The experimental group showed a significantly lower state anxiety score (F=5.30, p=.027, partial ${\eta}^2=.12$, observed power .61) than that of the control group. Conclusions: This educational program was effective on nursing students' cultural competence. Therefore, it is suggested that this program be used for other nursing students. It is also necessary to evaluate its effects after a longer period.

• Journal of Korean Biological Nursing Science
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• v.16 no.1
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• pp.8-16
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• 2014

Purpose: This study determined the effect of inter dental brush education on the dental plaque index, and the degree of halitosis for elementary school students. Methods: The study was performed on a non-equivalent control group, with a pre-test and post-test design. The study was intended for a total of 50 students. They were divided into two groups; an experimental group of 25 students and a control group of 25 students. The experimental group participated in inter dental brush education. The education took about 20 minutes, and was provided once a week, for a total of three weeks. To quantify the effect, the two groups were compared in terms of the dental plaque index and the degree of halitosis. Results: Without inter dental brush education, or a test for homogeneity, in the sense of exact equivalence of the dental plaque index and the degree of halitosis between the experimental and the control group, was supported. (p>.799, p>.876). 1) The first hypothesis, "The experimental group, who participated in inter dental brush education, would reveal a lower dental plaque indices than the control group", was supported (t=5.78, p<.001). 2) The second hypothesis, "The experimental group, who participated in inter dental brush education, would reveal a lower degrees of halitosis than the control group", was supported (t=4.49, p<.001). Conclusion: The proposed inter dental brush education is effective in improving the dental plaque index and the degree of halitosis for elementary school students.

• Journal of Korean Biological Nursing Science
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• v.15 no.4
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• pp.237-246
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• 2013

Purpose: A few Korean studies have reported that low urine acidity and hyperuricemia are related to metabolic syndrome. Therefore, we evaluated the relationships between urine pH, serum Uric Acid (UA), and metabolic risk factors in university students. Methods: Data were obtained from student health examinations in one university. Participants were 3,412 male and 4,214 female students. Descriptive statistics, t-test, logistic regressions and multiple logistic regression using SPSS version 18.0 were performed. Results: No significant relationship was found between metabolic risk factors and urine pH. From the univariate analysis, serum UA was significantly higher in obese ($BMI{\geq}25$), elevated blood pressure ($SBP{\geq}130$ and $DBP{\geq}85$), and higher triglyceride (${\geq}150$) groups for males and in obese, higher triglyceride and fasting blood sugar (${\geq}100$), and lower HDL-cholesterol (<50) groups for females. From the results of multivariate analysis, age, BMI, and triglyceride were significantly related to serum UA in males, BMI and HDL-cholesterol were significantly related to serum UA in females. Conclusion: Although there was no significant relationship between urinary pH and metabolic risk factors, significant associations between some of the metabolic risk factors and serum UA were found in the young adult population. Further studies are required to know the exact pathway between serum UA and metabolic syndrome.

• Journal of the Korea Institute of Building Construction
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• v.12 no.3
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• pp.347-357
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• 2012

While it is generally possible to install curved panels manufactured in a factory within the permitted error range on an irregular surface frame of concrete or steel, it is difficult and expensive. Freeform architecture is thus designed and constructed differently from formal buildings. In order to more easily and inexpensively actualize freeform architecture, Building Information Modeling (hereinafter referred to as BIM) has recently been applied in the construction industry. However, the related research and case analyses are not sufficient to identify the implications and contributions of freeform buildings in future similar projects. Therefore, this research will study design and construction methods for freeform surfaces, particular the concrete surface frame of freeform buildings based on BIM, focused on the Tri-Bowl project. This study attempts to analyze the pros and cons of each method for the concrete surface frame of the Tri-Bowl, and then presents the lessons learned and implications related to the design and construction process of the freeform architecture. Several implications for design and construction of concrete surface frame of the freeform building, the Tri-Bowl, are found. The first is that manufacturing and installation of a curved concrete frame is precisely performed based on the exact numerical values of materials and installation made using BIM 3D technologies, such as CATIA and Rhino. The second is that close and continuous collaboration among the different participants in the construction of the Tri-Bowl allowed them to cope with virtual conditions. The third is that design and construction processes have changed, and high quality of the surface frame of a freeform building is required.

• Journal of Korean Academy of Nursing
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• v.41 no.2
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• pp.245-255
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• 2011

Purpose: This study was conducted to examine the effects of simulation-based education regarding care in a cardio-pulmonary emergency care as related to knowledge, clinical performance ability, and problem solving process in new nurses. Methods: An equivalent control group pre-post test experimental design was used. Fifty new nurses were recruited, 26 nurses for the experimental group and 24 nurses for the control group. The simulation-based cardio-pulmonary emergency care education included lecture, skill training, team-based practice, and debriefing, and it was implemented with the experimental group for a week in May, 2009. Data were analyzed using frequency, ratio, chi-square, Fisher's exact probability and t-test with the SPSS program. Results: The experimental group who had the simulation-based education showed significantly higher know-ledge (t=5.76, p<.001) and clinical performance ability (t=5.86, p<.001) for cardio-pulmonary emergency care compared with the control group who had traditional education but problem solving process was not included (t=1.11, p=.138). Conclusion: The results indicate that a simulation-based education is an effective teaching method to improve knowledge and clinical performance ability in new nurses learning cardio-pulmonary emergency care. Further study is needed to identify the effect of a simulation-based team discussion on cognitive outcome of clinical nurses such as problem solving skills.

• Journal of Korean Academy of Nursing
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• v.40 no.2
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• pp.151-160
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• 2010

Purpose: The purpose of this study was to evaluate the effects of teaching method using Standardized Patients (SPs) on nursing competence, self-directed learning readiness, and problem solving ability-focusing on subcutaneous insulin injection. Methods: This research was a nonequivalent control group non-synchronized post-test design. The subjects consisted of 62 junior nursing students at E University. Scenarios to train SPs and checklists to evaluate the students' competence were developed by our research team. The experimental group (n=31) participated in the teaching class using SPs. The control group (n=31) received traditional practice education. The collected data were analyzed with descriptive analysis, $\chi^2$/Fisher's exact test, t-test, Pearson's correlation coefficient, and Cronbach's $\alpha$ using SPSS WIN 14.0 Program. Results: The mean scores of competence, self-directed learning readiness, and problem solving were significantly higher in the experimental group than the control group. Conclusion: As confirmed by this research findings, the teaching method using SPs was more effective than the traditional method to improve junior nursing students' competence, self-directed learning readiness, and problem solving. Therefore, It is necessary to develop a various of scenarios and to testify their effectiveness.