• Geophysics and Geophysical Exploration
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• v.9 no.1
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• pp.30-36
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• 2006

Japan's first pilot-scale $CO_2$ sequestration experiment has been conducted in Nagaoka, where 10400 t of $CO_2$ have been injected in an onshore aquifer at a depth of about 1100 m. Among various measurements conducted at the site for monitoring the injected $CO_2$, we conducted time-lapse crosswell seismic tomography between two observation wells to determine the distribution of $CO_2$ in the aquifer by the change of P-wave velocities. This paper reports the results of the crosswell seismic tomography conducted at the site. The crosswell seismic tomography measurements were carried out three times; once before the injection as a baseline survey, and twice during the injection as monitoring surveys. The velocity tomograms resulting from the monitoring surveys were compared to the baseline survey tomogram, and velocity difference tomograms were generated. The velocity difference tomograms showed that velocity had decreased in a part of the aquifer around the injection well, where the injected $CO_2$ was supposed to be distributed. We also found that the area in which velocity had decreased was expanding in the formation up-dip direction, as increasing amounts of $CO_2$ were injected. The maximum velocity reductions observed were 3.0% after 3200 t of $CO_2$ had been injected, and 3.5% after injection of 6200 t of $CO_2$. Although seismic tomography could map the area of velocity decrease due to $CO_2$ injection, we observed some contradictions with the results of time-lapse sonic logging, and with the geological condition of the cap rock. To investigate these contradictions, we conducted numerical experiments simulating the test site. As a result, we found that part of the velocity distribution displayed in the tomograms was affected by artefacts or ghosts caused by the source-receiver geometry for the crosswell tomography in this particular site. The maximum velocity decrease obtained by tomography (3.5%) was much smaller than that observed by sonic logging (more than 20%). The numerical experiment results showed that only 5.5% velocity reduction might be observed, although the model was given a 20% velocity reduction zone. Judging from this result, the actual velocity reduction can be more than 3.5%, the value we obtained from the field data reconstruction. Further studies are needed to obtain more accurate velocity values that are comparable to those obtained by sonic logging.

• Journal of Korean Academy of Nursing
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• v.20 no.3
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• pp.414-429
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• 1990

Numerous research reports have substantiated the role of stressful life events in relation to the onset of health changes. The relationship tends to hold across different age groups. Theoretically, adolescence has been considered a developmental crisis period of great stress, impoverished coping skills and high vulnerability to biological, social and psychological demands. The research problem addressed by this study was to examine the relationships between stressful life events and health symptom patterns, and the effect of two variables, coping and social, support, theoretically considered to mediate the relationship between stress and health symptoms in adolescents. The following five hypotheses were tested in this research : 1. Health symptoms are positively related to stressful life events in adolescents, 2. Health symptoms are negatively related to coping in adolescents, 3. Health symptoms are negatively related to social support in adolescents, 4. When coping is controlled, the relationship between health symptoms and stressful life events will decrease, and 5. When social support is controlled, the relationship between health symptoms and stressful life events will increase. The study subjects consisted of 1090 high school students of the metropolitan city of Seoul. The following sampling procedure was used : 1. Of the 169 high schools in nine school administrative districts in the city, a proportional sample of ten schools was selected. 2. One class from each of the freshman and sophomore was randomly selected and all the students who were in the sampled class were used as the study sample. The study was limited to freshman and sophomore adolescents, aged 15 to 18(mean＝16.6). Of the 1090 subjects 688(63%) were boys and 402(37%) were girls. An Adolescent Inventory of Stressful Life Events, a Health Symptom Questionnaire and an Adolescent Coping Inventory were adapted for this study. The Norbeck Social Support questionnaire was utilized to collect the data on perceived social support. Five high school teachers in the areas of school health and counselling reviewed the items of each questionnaire for content validity. A pilot study was undertaken to ascertain reliability. Fifty three high school students responded to the questionnaires and gave their opinions on the items. For stressful life events, health symptoms, coping, and social support, the Cronbach's alpha's on the study were .70, .94, .77, and .76, respectively. Research assistants attended all the sampled classes with the school proctor to explain the purpose and procedures of the study to the students. The questionnaires along with a ballpoint pen were distributed to the students who were asked to complete each item. The research assistants left the ballpoint pen with the students as a gift for their cooperation. An average of 50 minutes was required to complete the questionnaires. Using an SPSS, the first, three hypotheses were tested using Gamma, a measure of association for ordinal variables. Partial gamma was used to test the fourth and fifth hypotheses. Patterns of elaboration described by Babbie were selected to interpret the relationship of the three variable analyses. The significance of gamma was determined by Chisquare at a .05 level of significance. There was a positive relationship between health symptoms and stressful life events(Gamma＝.35, p＝.000). Thus the first hypothesis was supported. Unexpectedly, coping was positively related with health symptoms(Gamma＝.13, p＝.000). That is, the higher the coping levels, the greater number of health problems. The third hypothesis, the higher the level of social support, the fewer the health symptoms, was not accepted in this adolescent study group. When coping was controlled, under the condition of low coping the association between health symptoms and stressful life events increased significantly to a partial gamma of .39, and under the condition of high coping it was .30. According to the elaboration model, when one partial relationship is the same or greater than the original and the other is smaller, the control variable should be considered to be specifying the conditions. When social support was controlled the relationship between stressful life events and health symptoms increased under the condition of low social support, but with high social support, the relationship decreased. Both partial gamma were statistically significant at .05 level(.43 and .26 relatively). It can be interpreted that stressful life events are strongly and positively related to health symptoms under the condition of low social support, however this relationship can not be expected with high social support. Thus, the last two hypotheses were conditionally sustained. In this study, the relationships between stressful life events and health symptoms, and the specified me diating roles of coping and social support were found to have statistical interaction. This finding supports the theoretical position of this study. It suggests that stressful life events would create high susceptability to biological social and psychological health symptoms and coping and social support buffering the relationship between stressful life events and health symptom. The findings of this study have implications for nursing practice. When adolescents are confronted with non-developmental life events that are perceived as stressful, nurses should recognize the evidence of the stress-buffering effect of coping and social support on health symptoms and utilize the diverse sources of social support that are readily available to adolescents.

• The korean journal of orthodontics
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• v.37 no.2 s.121
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• pp.98-113
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• 2007

Objective: The purpose of this study was to evaluate the displacement pattern and the stress distribution shown on a finite element model 3-D visualization of a dry human skull using CT during the retraction of upper anterior teeth. Methods: Experimental groups were differentiated into 8 groups according to corticotomy, anchorage (buccal: mini implant between the maxillary second premolar and first molar and second premolar reinforced with a mini Implant, palatal: mini implant between the maxillary first molar and second molar and mini implant on the midpalatal suture) and force application point (use of a power arm or not). Results: In cases where anterior teeth were retracted by a conventional T-loop arch wire, the anterior teeth tipped more postero-inferiorly and the posterior teeth moved slightly in a mesial direction. In cases where anterior teeth were retracted with corticotomy, the stress at the anterior bone segment was distributed widely and showed a smaller degree of tipping movement of the anterior teeth, but with a greater amount of displacement. In cases where anterior teeth were retracted from the buccal side with force applied to the mini implant placed between the maxillary second premolar and the first molar to the canine power arm, it showed that a smaller degree of tipping movement was generated than when force was applied to the second premolar reinforced with a mini implant from the canine bracket. In cases where anterior teeth were retracted from the palatal side with force applied to the mini implant on the midpalatal suture, it resulted in a greater degree of tipping movement than when force was applied to the mini implant between the maxillary first and second molars. Conclusion: The results of this study verifies the effects of corticotomies and the effects of controlling orthodontic force vectors during tooth movement.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.1
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• pp.209-224
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• 2020

This study started from the question of whether the preference of corporate recruitment can be achieved without any difference between the start-up experiencer and the general job seekers. Therefore, the purpose of the study is to identify the factors related to start-ups that affect the preference of job seekers for companies, and to analyze the differences in the factors related to start-ups between general job seekers and job seekers with start-up experience. Third, it is to see the difference in the preference for employment between job seekers with start-up experiences and general job seekers. The independent variables of the research model were entrepreneurship, motivation for start-up (job search), and characteristics of the job seekers (founder). The dependent variables were job preference, and the moderating variables were presented as job seekers' classification (job seekers with start-up experience vs. general job seekers). The subjects of the study were personnel managers of 100 companies with more than 5 years of establishment and 100 new companies with less than 5 years of establishment. The questionnaire was distributed in two types, and 189 respondents, including 101 job seekers with start-up experiences and 88 general job seekers, were finally used for analysis. The results of the study were as follows. First, as a result of multiple regression analysis on both experienced start-up experiencers and general job seekers, only entrepreneurship had an effect on preference for recruitment. Second, the moderating effect of job seekers' classification was found only in the relationship between motivation for start-up and preference for employment. Third, the result of multiple regression analysis based on the start-up experiencers showed that the relationship between the motivation for start-up, the preference for recruitment, the characteristics of founders and the preference for recruitment was statistically significant. On the other hand, the characteristics of the founder and the preference for employment were rejected. Fourth, the results of the study based on general job seekers showed that the motivation for job search decreased the preference for employment. The study did not provide the results of differences in recognition between different industries, traditional enterprises and venture businesses due to the limitation of small examples. There is no clear definition of start-up experiencers either. However, it is meaningful to suggest the implications of what preparations should be made when the start-up experiencers close their start-ups and turn their career into employment and to help them to accurately recognize the importance of entrepreneurship. It also provides the preference of the general job seekers for the company, the preparation for successful employment, and the implications for the direction of the future start-up revitalization.

• Korean Journal of Environment and Ecology
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• v.26 no.2
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• pp.273-282
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• 2012

This study has estimated Gyeongju National Park's natural environment and cultural relic value in the same way and then been performed to compare the size of the value. Representative method to measure environmental property is contingent valuation methods, CVM. The variables and estimated models adopted for the calculation were same and the respondents were asked by distinguishing between the amount which they would pay to preserve the natural environment and that which they were willing to pay to preserve the cultural relics. As the result, WTP(Willing to pay), the amount that they were willing to pay to preserve the natural environment of Gyeongju National Park was 17,838 won per person and that to preserve the cultural relics appeared to be 316,248 won per person. Based on this, it was estimated that the value of the natural environment with which Gyeongju National Park provided annual visitors was 47 billion won and that the annual value of the cultural relics was 845.7 billion. If the natural environment and the cultural relics value elements are united, it can be estimated that the natural environment and cultural relic value got at the time of people's first visit to Gyeongju National Park is 334,086 won and that the annual value is 893.4 billion won. In this study, the value of the cultural relics has been estimated 18 times higher than that of the natural environment. This reason was that visitors judged that a total of 66 cultural properties including 11 national treasures, 23 treasures, 13 historic places, one historic sites and scenic spot and 18 local cultural properties, etc. which were distributed in Gyeongju National Park were worth far more than the natural environment. Based on the result of this study, the operating management plan of Gyeongju National Park should include a differentiated operation strategy through consultation with relevant experts by taking into account characteristics of the physical components.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.360-367
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• 2015

The present study investigated the habitats of Korean fir trees (Abies koreana E. H. Wilson) on Mt. Baekwun (Baekwun-san), determined the current distribution, quantified the contribution of biological and non-biological environmental factors affecting the distribution, derived actual and potential habitats, presented a plan for the establishment of protected areas, applied RCP 8.5 climate change scenario to analyze the effects of climate change on the future distribution of Korean fir trees, and predicted future potential habitats. According to the results of the study, 3,325 Korean fir trees (DBH >= 2.5 cm) inhabited Mt. Baekwun, and their distribution area was approximately 150 ha. Populations of Korean fir trees were confirmed to exist at an altitude of 900 m above sea level and were distributed up to 1,200 m. Based on potential distribution, areas appropriate for habitation by Korean fir trees were analyzed to be 450 ha, three times the current distribution area, with a focus on Sang Peak (Sang-bong), Eokbul Peak (Eokbul-bong), Ddari Peak (Ddari-bong), and Dosol Peak (Dosol-bong). The forest stands near Sang Peak, the main peak, were evaluated as those with the most appropriate potential for the habitation of Korean fir trees, and populations of the trees tended to prefer the northern slope rather than the southern slope. When climate change scenario RCP 8.5 was applied and future potential distribution was analyzed, the habitats were expected to decrease in area to 20 ha by 2050, with a focus on Sang Peak, and areas appropriate for habitation were predicted not to exist by 2080. Judging from such results, as global warming accelerates, the habitats of Korean fir trees are clearly expected to move from lowlands to highlands.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1249-1256
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• 2016

Black ginseng (BG) obtained by a 9-fold steaming process of Panax ginseng has been reported to have anti-oxidative, anti-obesity, and anti-diabetes effects. The current study evaluated the protective effect of BG by steaming time in an HCl/ethanol-induced acute gastritis model. BG was divided into four samples according to steaming-drying processing (Gin1, Gin3, Gin6, and BG). High performance liquid chromatography analysis, free radical scavenging activity, and total phenol and flavonoid contents were examined in ginseng and four BG samples. Compared with ginseng, BG showed a stronger radical scavenging effect and higher contents of total phenol and flavonoids. To evaluate the anti-gastritic effect of BG, mice were distributed into five groups: normal mice (N), acute gastritic mice with distilled water (CON), acute gastritic mice with 100 mg/kg of ginseng (Gin0), acute gastritic mice with 100 mg/kg of BG (BG), and acute gastritic mice with 10 mg/kg of sucralfate (SC). After 1 hour of pre-treatment with water, extracts (Gin0 and BG), or drug (SC), experimental groups except for N were orally administered 0.5 mL of 150 mM HCl/60% ethanol (v/v) mixture. Blood was collected 1 hour later from the heart, and gastric tissue was harvested. Reactive oxygen species (ROS) levels were measured in serum, and related protein expression was examined by Western blot assay. In HCl/ethanol-induced acute gastritic mice, treatment with ginseng or BG improved mucosal damage in the histological evaluation. The serum ROS level significantly decreased in the BG-treated group compared with the CON group. Furthermore, expression of inflammatory cytokines significantly decreased in the BG-treated group compared with the CON group. Based on these results, antioxidant and anti-gastritic activities of ginseng were enhanced by streaming-drying processing, in part due to an increase in biological active compounds.

• Asia pacific journal of information systems
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• v.21 no.1
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• pp.1-27
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• 2011

In an attempt to cope with widespread, dynamic, and accelerating changes in both internal and external business environments, companies often utilize information technologies such as SCM(Supply Chain Management). To date, SCM research has mainly focused on the effects of dynamic factors on SCM success and emphasized adoption strategies and critical success factors. Consequently, the effects of more static factors such as interdependency between SCM partners have been largely ignored. The purpose of this study, therefore, is to examine the effects of both dynamic and static factors on SCM performance by controlling for information quality and partnership quality. The five factors examined in this study include innovative ness, mutual dependency, quality of information, partnership quality, and SCM performance. All factors were examined from the perspective of part suppliers, except the mutual dependency which was examined from two aspects: supplier's dependency on customer and customer's dependency on supplier. Data was collected through five hundred survey questionnaires distributed to the part supplier companies that have implemented SCM systems for at least one year. As a result, a total of 170 valid responses were obtained. A structural equation research model was fitted using SAS 9.1.3 and SMART-PLS 2.0. The results of this study can be summarized as follows. First, innovativeness positively affected SCM information quality. SCM partnership quality, and ultimately SCM performance. The path coefficient between innovativeness and information quality was 0.387, with a t-value of 3.528. Innovativeness also had a positively direct effect on partnership quality. The path coefficient was 0.351 with a t-value of 3.366. The total effect of innovativeness on partnership quality was significant, although its indirect effect on partnership quality by altering information quality was negligible. The total indirect effect of innovativeness on SCM performance by affecting information quality and partnership quality was significant with a p-value of 0.014. Innovativeness played an important role in determining SCM performance. Second, mutual dependency showed no significant effect on SCM information quality. This result contradicts the earlier assertion that the more dependent two companies are, the more accurate and timely the information they exchange ought to be. This study showed that this may not be the case; a partner may provide information of poor quality even when it is strongly dependent on the other. Mutual dependency showed significant effect on partnership quality. However, when the mutual dependency perceived by suppliers was divided into two parts, one being a supplier's dependency on its customer company and the other being a customer's dependency on the supplier, the latter showed a significant impact on the perceived SCM partnership quality. This result indicates that a customer company can hardly improve the partnership quality perceived by suppliers by making them more dependent. It improves only when the suppliers perceive that their partners, typically having more bargaining power, are more dependent on them. The overall effect of mutual dependency of any kind on SCM performance, however, was not significant. Although mutual dependency has been mentioned as an important static factor influencing almost every aspect of cooperation on a supply chain, its influences may not be as significant as it was initially perceived to be. Third, the correlation between information quality and partnership quality was 0.448 with a p-value of less than 0.001. Information quality had a path coefficient of 0.256 to partnership quality with a t-value of 2.940. The quality of information exchanged between partners may have an impact on their partnership quality. Fourth, information quality also had a significant impact on SCM performance with a path coefficient of 0.325 with a t-value of 3.611. In this study, SCM performance was divided into four categories: product quality, cost saving, service quality, and order fulfillment. Information quality has Significant impacts on product quality, cost saving and service quality, but not on order fulfillment. Fifth, partnership quality, as expected, had a significant impact on SCM performance. The path coefficient was 0.403 with a t-value of 3.539. Partnership quality, like information quality, had positive impacts on product quality, cost saving and service quality, but showed no impact on order fulfillment. It seemed that order fulfillment is the hardest category of performance that SCM can satisfy. One major limitation of this study is that it surveyed only the suppliers. To better understand the dual aspects of SCM, it is important to survey both suppliers and the assemblers, especially in pairs. This research, to our best knowledge, was the first attempt to study the level of dependency between the two groups by measuring the dual aspects of SCM and studying mutual dependency from the categories of suppliers and assemblers each.. In the future, a more comprehensive and precise measurement of SCM characteristics needs to be achieved by examining from both the supplier's and assembler's perspectives.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.2
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• pp.53-62
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• 2013

Land-use/cover changes not only amplify or alleviate influence of climate changes but also they are representative factors to affect environmental change along with climate changes. Thus, the use of land-use/cover changes scenario, consistent climate change scenario is very important to evaluate reliable influences by climate change. The purpose for this study is to predict and analyze the future urban growth considering social and economic scenario from RCP scenario suggested by the 5th evaluation report of IPCC. This study sets land-use/cover changes scenario based on storyline from RCP 4.5 and 8.5 scenario. Urban growth rate for each scenario is calculated by urban area per person and GDP for the last 25 years and regression formula based on double logarithmic model. In addition, the urban demand is predicted by the future population and GDP suggested by the government. This predicted demand is spatially distributed by the urban growth probability map made by logistic regression. As a result, the accuracy of urban growth probability map is appeared to be 89.3~90.3% high and the prediction accuracy for RCP 4.5 showed higher value than that of RCP 8.5. Urban areas from 2020 to 2050 showed consistent growth while the rate of increasing urban areas for RCP 8.5 scenario showed higher value than that of RCP 4.5 scenario. Increase of urban areas is predicted by the fact that famlands are damaged. Especially RCP 8.5 scenario indicated more increase not only farmland but also forest than RCP 4.5 scenario. In addition, the decrease of farmland and forest showed higher level from metropolitan cities than province cities. The results of this study is believed to be used for basic data to clarify complex two-way effects quantitatively for future climate change, land-use/cover changes.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.148-152
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• 2004

본 연구에서는 물순환의 재생이나 보전에 필수적인 유역 물순환의 정량화와 유역변화의 영향예측을 위해 개발된 WEP (Water and Energy Transfer Process) 모형의 국내 유역에 내한 적용성을 검토하고, 청계천 유역의 물순환 양상을 모의하였다. WEP 모형은 복잡한 토지이용이 이루어지고 있는 도시하천 유역에 내한 물순환의 정량화를 목적으로 일본의 토목연구소 (PWRI; Public Works Research Institute), 과학기술진흥사업단, Jia 박사 등에 의해 공동으로 개발되었으며 지표면 및 비포화 토양층의 물${\cdot}$열 플럭스 계산, 하도흐름의 추적계산 및 지하수 유동계산, 격자내 토지이용의 불균질성 반영 등이 가능한 물리적인 기반의 공간 분포형 모형 (Physically Based Spatially Distributed)이다. 모형을 적용한 청계천 유역 (유로연장 13.75 km, 유역 면적 $50.96km^2$)은 전체 토지이용중 도시지역이 $75.9\%$를 차지하고, 유역내 인구가 120만명에 이르는 도시유역으로 높은 불투수 면적비율, 인공계 물순환 요소의 영향 등의 도시 유역 특성이 물순환의 구조 전반에 미치는 영향에 대한 연구가 부족하였다. WEP 모형 적용 결과, 모의 기간 동안의 하천 유출량은 실측치에 근사한 값을 나타내었으며 유역의 물순환 양상을 모의할 수 있었다. 청계천 유역은 전형적인 도시 유역의 특성을 보여주었는데, 강우시의 직접유출이 크고, 강우의 유출에 대한 반응이 빠르며, 증발산의 경우는 산림지역보다 도시지역이 상대적으로 적은 것으로 분석되었다. 이번 연구를 통하여 WEP 모형이 유역 물순환 해석에 적절한 모형임을 확인할 수 있었으면, 향후 청계천 유역의 물리적 특성에 대한 매개변수와 인공계 물순환 자료의 보완을 통해 보다 향상된 모의가 가능할 것으로 판단된다. 하였던 Cd과 Mg이 Ca 및 Ca과 vitamin D의 동시(同時) 급여(給與)로 감소(減少)하였고 Cu는 전체적(金體的)으로 변화(變化)가 없었으며 Zn은 Cd 급여(給與)로 감소(減少)하였으나 Ca과 vitamin D의 급여(給與)에 의하여 증가(增加)하였고 Ca은 Ca과 viamin D의 급여(給輿)로 유의(有意)하게 증가(增加)하였다. 신장(腎臟)중의 무기질(無機質) 함량(含量)은 Cd급여(給輿)로 Cu, Mg은 감소(滅少)하였으나 Ca, Zn은 변화(變化)가 없었고 Ca 및 Ca과 Vitamin D의 급여(給與)로 Cd, CU, Zn은 증가(增加)하였다.ce area)는 수술 전100.8$\pm$25.6 mm/$m^{2}$에서 79.3$\pm$ 15.8 mm/$m^{2}$로 감소한 소견을 보였다. 승모판 성형술은 전 승모판엽 탈출증이 있는 두 환아에서 동시에 시행하였다. 수술 후 1년 내 시행한 심초음파에서 모든 환아에서 단지 경등도 이하의 승모판 폐쇄 부전 소견을 보였다. 수술 후 조기 사망은 없었으며, 합병증으로는 유미흉이 한 명에서 있었다. 술 후 10개월째 허혈성 확장성 심근증이 호전되지 않아 Dor 술식을 시행한 후 사망한 예를 제외한 나머지 6명은 특이 증상 없이 정상 생활 중이다 결론: 좌관상동맥 페동맥이상 기시증은 드물기는 하나, 영유아기에 심근경색 및 허혈성 심근증 또는 선천성 승모판 폐쇄 부전등을 초래하는 심각한 선천성 심질환이다. 그러나 진단 즉시 직접 좌관상동맥-대동맥 이식술로 수술적 교정을 해줌으로써 좋은 성적을 기대할 수 있음을 보여주었다.특히 교사들이 중요하게 인식하는 해방적 행동에 대한 목표를 강조하여 적용할 필요가 있음을 시사하고 있다.교하여 유의한 차이가 관찰되지 않았다. 또한 HSP 환자군에서도 $IL1RN^{*}2$ allele 빈도와 carriage