• Journal of Technologic Dentistry
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• v.20 no.1
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• pp.37-49
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• 1998

The specimens used were Ag-25 Pd-15 Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electric furnace and centrifugal casting machine in Ar atmosphere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age- hardening characteristics of the small Au-containing Ag-Pd-Cu dental alloys were investigated by means of hardness testing. X-ray diffraction and electron microscope observations, electrical resistance, ergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, i.e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the $L1_0$ type face-centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affected by the Cu concentration. In stage II, decomposition of the ${\alpha}$ solid solution to a PdCu ordered phase($L1_0$ type) and an Ag-rich ${\alpha}2$ phase occurred and a discontinuous precipitation occurred at the grain boundary. From the electron microscope study, it was conclued that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipetation procedure was ${\alpha}{\to}{\alpha}+{\alpha}_2+PdCu {\to}{\alpha}_1+{\alpha}_2+PdCu$ at Pd/Cu = 1.7 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

• The Journal of Korean Academic Society of Nursing Education
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• v.5 no.2
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• pp.177-190
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• 1999

This study has been conducted on the basis of the literature review of Nursing Education Research in China from 1990 through August 1998. Its purpose was to support the basic data of nursing education which is risen as major revolutionary of nursing in China and those for exchange of information between Korea-China nursing education. It is retrospective and descriptive research analyzing one hundred eighty articles published in The Journal of China Nursing. The results of the study were as follows. 1. Only 33.3% of the professors of Technical Nursing School who have played of major role of nursing education in China have carried out the study related to nursing education. Baccalaureate program professors have marked 22.2% of all studies, and diploma program professors have done 12.2% of all. Therefore, the professors of above the diploma program have done total 44.4%. It explains that the professors of baccalaureate and diploma programs have done more studies related to nursing education than those of Technical Nursing School. 2. In terms of the study design, most of the studies(38.8%) were case studies introducing the curriculum contents that were done at education institutions. And then, 28.5% were reviewing the articles, and 15.6% were descriptive studies. 3. In terms of the content of the study, 38.3% were relevant to education of Technical Nursing School, 15.0% were about baccalaureate education, and 10.4% is about diploma. 4. To analyze the specific contents of the studies ; a. In baccalaureate program, human resources (professor or teaching), course extension, lab, classes, teaching method, education philosophy, goal of education, evaluation method, and human resource development were included. b. In diploma program, teaching contents evaluation method, teaching method, and educational system were included c. In the technical school, there were qualification of professors , teaching method, evaluation method, opening the courses, teaching contents, goal of education and so on. d. Beyond these, there were practice guidance and appraisement, teaching method, and opening new courses which were not specially indicated as educational curriculum and score management as continuing education. What is above tell us that the study regarding development of university system has been progressed actively and widely. It has been for the effort of revolution which based on the China government force to reform of nursing education process during last 10 years. On the base of the result, we suggest the following questions and the alternatives. 1) Since most articles are case studies related to teaching methods and the others doesn't propose the research method. the study which is applied more exact research method is needed. 2) No study is regarding social change and health policy. Because University program, founded in 1983 is on the beginning point, the research about curriculum have to be taken as a top priority as well as to reflect social needs which are based on social changes and national health policy 3) Only one review article study tells nursing Human resource. To appear in large numbers in nursing manpower, avoid the present hospital nurses training system. Then, the study for manpower development which is able to accomplish in many fields has to be advanced. 4) Most studies did not have literature review processes, so it was impossible for researcher to know the past study tendency and there is no relation among studies as to same subject, the education about research method is needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.213-220
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• 2012

This study was conducted on 4th and 5th grade elementary school students in Daegu, Korea for the purpose of promoting health and proper dietary habits. A children food safety education program was developed and its effects evaluated on 4th and 5th graders (3,932 students for 4th year, 4,438 students for 5th year) at 46 elementary schools, which were under the jurisdiction of the four educational bureaus of Daegu city. Education was conducted in accordance with an education design plan, of which there were two goals, including know the contents of 'special act on children's dietary life safety management' and 'practice proper hand-washing'. 'Special act on children's dietary life safety management' was explained, and the education curriculum included proper hand-washing for prevention of food poisoning, quality certification mark on children's favorite foods, harmful foods such as unsanitary and adulterated foods, and green food zone. Flash songs, PowerPoint, 'glitter burger' notice note, and banner were used as education media. It was found that the awareness level of items related to 'special act on children's dietary life safety management' increased significantly after education (p<0.001). 'Necessity of nutrition education and children's food safety' also increased significantly (p<0.05) after education. Lastly, children answered that they washed their hands more often after education (62.9%) than before (60.7%).

• Tuberculosis and Respiratory Diseases
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• v.60 no.3
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• pp.330-336
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• 2006

Background : Aquaporins (AQPs) may play a role in the pathogenesis of pulmonary inflammation and edema. This study investigated the role ofAQPs in acute lung injury following bleomycin inhalation in rats. Methods : Sprague-Dawley rats were treated via inhalation with 10 U/kg bleomycin hydrochloride dissolved in 5 ml of normal saline. The control rats were treated with 5 ml normal saline. The animals (n = 6-8 rats per group) were sacrificed at 4, 7, and 14 d. The changes in AQP1, AQP4, and AQP5 expression levels over time were analyzed by Western blotting. The nitrate and nitrite concentrations in the bronchoalveolar lavage fluid (BALF) were measured using a modified Griess reaction. ELISA was used to check cytokines. Results : The respiration rates were significantly higher 4 and 7 days after the bleomycin treatment compared with those of the control rats. The tidal volume was lower in rats at 4 days after the bleomycin treatment, and the wet/dry weights of the lung were significantly higher than those of the control group. The nitrite and nitrate concentrations in the BALF from the rats at 4 days after exposure to bleomycin were greater than those from the saline-treated rats. Immunoblotting studies demonstrated that the AQP1 and AQP4 expression levels were lower in the rats at 4 days. However, the AQP4 expression level was higher at 7 days. The AQP5 expression level increased at 4, 7 and 14 days after the bleomycin treatment. Conclusion : This study demonstrates that AQPs are expressed differently in bleomycin-induced pulmonary edema.

• Progress in Medical Physics
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• v.19 no.2
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• pp.89-94
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• 2008

TomoTherapy has a merit to treat cancer with Intensity modulated radiation and combines precise 3-D imaging from computerized tomography (CT scanning) with highly targeted radiation beams and rotating beamlets. In this paper, we comparing the dose distribution between TomoTherapy and linear accelerator based intensity modulated radiotherapy (IMRT) for 10 Head & Neck patients using TomoTherapy which is newly installed and operated at National Cancer Center since Sept. 2006. Furthermore, we estimate how the homogeneity and Normal Tissue Complication Probability (NTCP) are changed by motion of target. Inverse planning was carried out using CadPlan planning system (CadPlan R.6.4.7, Varian Medical System Inc. 3100 Hansen Way, Palo Alto, CA 94304-1129, USA). For each patient, an inverse IMRT plan was also made using TomoTherapy Hi-Art System (Hi-Art2_2_4 2.2.4.15, TomoTherapy Incorporated, 1240 Deming Way, Madson, WI 53717-1954, USA) and using the same targets and optimization goals. All TomoTherapy plans compared favorably with the IMRT plans regarding sparing of the organs at risk and keeping an equivalent target dose homogeneity. Our results suggest that TomoTherapy is able to reduce the normal tissue complication probability (NTCP) further, keeping a similar target dose homogeneity.

• Investigative Magnetic Resonance Imaging
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• v.4 no.1
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• pp.27-33
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• 2000

Purpose: To determine the electronic spin relaxation times, $T_{le}$, of three commercially available Gd-chelated MR contrast agents, Gd-DTPA, Gd-DTPA-BMA and Gd-DOTA, using Electron Paramagnetic Resonance(EPR) technique. Material and Methods: The paramagnetic MR contrast agents, Gd-DTFA(Magnevist) , Gd-DTFA-BMA(OMNISCAN) and Gd-DOTA(Dotarem), were used for this study, The EPR spectra of these contrast agents, which were prepared 2:1 methanol/water solution, were obtained at low temperatures, from $-160^{\circ}C~20^{\circ}C$. The glassy-state EPR spectra for these contrast agents were then fitted by the simulation spectra generated with different zero-field splitting (ZFS) parameters by a computer simulation program 'GEN', which generates the EPR powder spectrum using a given ZFS in $3{\times}3$ tensor. Finally, the spin relaxation times of the contrast agents were then determined from the $T_{2e}$, D, and E values of the best simulation spectra using the McLachlan's theory of average relaxation rate. Results: The electronic transverse spin relaxation times, $T_{2e}'s$, of Gd-DTPA, Gd-DTPA-BMA and Gd-DOTA were 0.113ns, 0.147ns and 1.81ns respectively. The g-values were 1.9737, 1.9735 and 1.9830 and the electronic spin relaxation times, $T_{1e}'s$, were 18.70ns, 33.40ns and $1.66{\mu}s$, respectively. Conclusion: The results of these studies reconfirm that the paramagnetic MR contrast agents with larger ZFS parameters should have shorter $T_{1e}'s$. Among three contrast agents used for this study, Gd-DOTA chelated with cyclic ligand structure shows better electronic property then the others with linear structure. Thus, it is concluded that the exact determination of ZFS parameters is the important factor in evaluating relaxation enhancement effect of the agents and in developing new contrast agents.

• Clinical and Experimental Pediatrics
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• v.49 no.8
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• pp.870-874
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• 2006

Purpose : Popular use of fetal ultrasonography has increased to detect congenital hydronephrosis(CH) which is the most common anomaly prenatally detected. We'd like to determine the frequency and clinical characteristics of prenatally diagnosed CH and outcome of ureteropelvic junction stenosis(UPJS). Methods : The records of births between January 1994 and June 2003 in Chonnam National University Hospital(CNUH), and the records of children who were diagnosed with CH in the Department of Pediatrics of CNUH during the above period, were retrospectively analyzed. In the patients with UPJS, the initial anterior posterior diameters of renal pelvis(APD) were compared between the spontaneous regression (SR) and operation group(OP). In the SR group, sequential regression rates of APD were estimated. Results : Among a total 9,076 births, 231(2.54 percent) patients with 293 renal units were diagnosed as CH and 19(6.78 percent) renal units spontaneously regressed 3 days after birth. In 228 children(56 bilateral; 172 unilateral; total 284 renal units) diagnosed with CH in the department of pediatrics of CNUH, male(71.9 percent) and left kidney(69.2 percent) predilection were found and 78.1 percent of CH were caused by UPJS. The initial APD of the SR group(121 units) in UPJS was $7.8{\pm}6.28mm$, which was significantly smaller than the APD($26.8{\pm}12.14mm$) of the OP group(25 unit)(P<0.05). In the SR group, 81 percent spontaneously regressed within one year. Conclusions : In CH, male and left kidney predilection were found. UPJS was the most common cause of CH and initial APD in UPJS at 3 days of age was a good prognostic indicator. Close monitoring should be done for at least one year because most SR in UPJS regressed spontaneously within one year.

• Clinical and Experimental Pediatrics
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• v.50 no.5
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• pp.476-483
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• 2007

Purpose : The objective of this study was to assess ventricular function by tissue Doppler imaging (TDI) in children with congenital heart disease (CHD) who have been undergoing open heart surgery (OHS) using cardiopulmonary bypass. We tried to compare the parameters of tissue Doppler imaging before and after OHS in patients with congenital heart disease. Methods : This study was conducted on 32 patients with CHD after OHS from January 2005 to December 2005 at Kyungpook National University hospital. Patients who underwent 2-D echocardiography before and after their OHS. All patients were divided into three groups, left ventricular volume overloading group (group 1), and right ventricular volume overloading group (group 2), and right ventricular pressure overloading group (group 3). The TDIs were examined before and 1 to 3 months after OHS. Peak early diastolic (E), and peak late diastolic (A) velocity of transmitral flow were measured by pulsed wave Doppler examination. Peak systolic (Sm), peak early diastolic (Em), and peak late diastolic (Am) velocity in apical 4-chamber and 2-chamber views were measured by TDI. The author calculated E/Em ratio. Results : The patients were 14 boys and 18 girls and the average age of patients was 2 years and 3 months. The congenital heart diseases which have to get OHS were ventricular septal defect (13 cases), atrial septal defect (7), atrioventricular septal defect (3), isolated pulmonary stenosis (2) and tetralogy of Fallot (7). There were significant decrease of Sm, Em, Am measured on tricuspid annulus and E/Em measured on mitral annulus in apical 4 chamber view (P<0.05). Conclusion : This study showed significant decrease of Sm, Em, Am measured on tricuspid annulus and E/Em measured on mitral annulus in apical 4 chamber view after OHS. These changes might be due to the effects of cardiopulmonary bypass in OHS and/or hemodynamic changes after correction of congenital heart disease. To clarify these changes, further study on more patients is needed.

• Journal of Plant Biotechnology
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• v.35 no.1
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• pp.87-94
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• 2008

Porcine epidemic diarrhea virus (PEDV) is an infectious and highly contagious virus of swine. In order to develop the transgenic tobacco culture cells producing PEDV antigen protein, four vectors expressing PEDV spike protein (SP) gene under the control of a CaMV 35S promoter were constructed. Four fragments of the SP region of PEDV, SP1 (444 bp, 1487-1930 bp), SP2 (1.7 kb, 2300-3987 bp), SP3 (1.4 kb, 1559-2950 bp), and SP4 (2.6 kb, 9-2643 bp) were amplified by PCR and then C-MYC tag was fused to the end of each SP gene, respectively. These cassettes are inserted into the pCAMBIA2300 (named as 35S::SP1-M, 35S::SP2-M 35S::SP3-M, and 35S::SP4-M, respectively). Tobacco (cv. BY-2) cultured cells were transformed by co-cultivation with Agrobacterium tumefaciens harboring expression vector. We selected kanamycin-resistant calli and checked for the presence of the introduced SP gene using PCR, resulting 70% of them showed the foreign gene. We selected the lines with high-level expression of PEDV antigen protein based on dot blot analysis. Southern blot analysis confirmed that the PEDV SP gene was integrated into the genome of the tobacco cultured cells. Northern blot analysis showed that the introduced gene was highly expressed in transgenic cultured cells. Transgenic tobacco cultured cells-derived antigen induced immunogenicity in mice as determined by a plaque reduction neutralization assay. These results suggest that the vectors expressing PEDV spike protein gene in this study will be useful for the development of transgenic plants and cultured cells producing PEDV antigene protein.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.3
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• pp.119-130
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• 2015

Impacts of Argo temperature assimilation on the analysis fields in the East Sea is investigated by using DAESROM, the East Sea Regional Ocean Model with a 3-dimensional variational assimilation module (Kim et al., 2009). Namely, we produced analysis fields in 2009, in which temperature profiles, sea surface temperature (SST) and sea surface height (SSH) anomaly were assimilated (Exp. AllDa) and carried out additional experiment by withdrawing Argo temperature data (Exp. NoArgo). When comparing both experimental results using assimilated temperature profiles, Root Mean Square Error (RMSE) of the Exp. AllDa is generally lower than the Exp. NoArgo. In particular, the Argo impacts are large in the subsurface layer, showing the RMSE difference of about $0.5^{\circ}C$. Based on the observations of 14 surface drifters, Argo impacts on the current and temperature fields in the surface layer are investigated. In general, surface currents along the drifter positions are improved in the Exp. AllDa, and large RMSE differences (about 2.0~6.0 cm/s) between both experiments are found in drifters which observed longer period in the southern region where Argo density was high. On the other hand, Argo impacts on the SST fields are negligible, and it is considered that SST assimilation with 1-day interval has dominant effects. Similar to the difference of surface current fields between both experiments, SSH fields also reveal significant difference in the southern East Sea, for example the southwestern Yamato Basin where anticyclonic circulation develops. The comparison of SSH fields implies that SSH assimilation does not correct the SSH difference caused by withdrawing Argo data. Thus Argo assimilation has an important role to reproduce meso-scale circulation features in the East Sea.