• Journal of Chest Surgery
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• v.42 no.2
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• pp.175-183
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• 2009

Background: Mitral valve abnormalities in the pediatric population are rare. Mitral valve replacement or pediatric mitral lesions can cause problems such as a lack of growth potential. There re only limited experiences with mitral valve repair at any institution, so the purpose of his study is to evaluate the outcomes of mitral valve repair n pediatric patients. Material and Method: Sixty-four consecutive children (28 males and 36 females) with a mean age of $5.5{\pm}4.7$ years underwent mitral valve repair for treating their congenital mitral valve disease between January 1996 and December 2005. The patients were divided into two groups: group 1 (34 patients (53.1%)) had isolated disease (mitral anomaly with or without trial septal defect or patent ductus arteriosus) and group 2 (30 patients (46.9%)) had complex disease (mitral anomaly with concurrent intracardiac disease, except atrioventricular septal defect). Result: The overall in-hospital mortality was 6.3%; group 1 had 5.9% mortality and group 2 had 10.0% mortality. The postoperative morbidity was 18.8%; group 1 and 2 had 14.7% and 23.3% postoperative morbidity, respectively, and there as no significant difference among the groups. The median follow-up was 4.6 years range: $0.5{\sim}12.2$ years). The 10-year survival rate was 95.3%. The 10-year freedom from re-operation rate was 76.1% with 10 re-operations. The majority of the functional classifications were annular dilatation and leaflet prolapse. A mean of $2.1{\pm}1.1$ procedures per patient were performed. The echocardiography that was done at the immediate postoperative period showed a significant improvement in the mitral valve function. The follow-up echocardiographic results were significantly improved. However, mitral stenosis newly developed over time, and there ere significant differences according to the repair strategies. Conclusion: The patients who underwent mitral valve repair for congenital mitral anomalies showed good results. The follow-up echocardiography revealed satisfactory short-term and long-term results. Close follow-up is necessary to detect the development of postoperative mitral stenosis or regurgitation.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.165-174
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• 2009

Background: With the advances of cardiac surgery, the demand for an artificial prosthesis has increased, and this has led to the development and utilization of diverse alternative materials. We conducted this research to improve an artificial prosthesis by examining the changes of the physical qualities, the pressure related tensile strength, the change in elasticity and the thermostability of a xenograft valve (porcine) and pericardium (bovine, porcine) based on the type of fixation liquid we used. Material and Method: The xenograft valves and pericardium were assigned into three groups: the untreated group, the fixed with glutaraldehyde (GA) group and the glutaraldehyde with GA+solvent such as ethanol etc. group. The surgeons carried out each group's physical activities. Each group's uniaxial tension and elasticity was measured and compared. Thermostability testing was conducted and compared between the bovine and porcine pericardium fixed with GA group and the GA+solvent group. Result: On the physical activity test in the surgeon's hand, no significant difference between the groups was sensed on palpation. For suture and tension, the GA+solvent group was slightly firmer than the low GA concentration group. In general, the circumferential uniaxial tension and elasticity of the porcine aortic and pulmonary valves were better in the fixed groups than that in the untreated group. There was no significant difference between the GA and GA+solvent groups (p>0.05). Bovine and porcine pericardium also showed no significant difference between the GA group and the GA+solvent group (p>0.05). When comparing between the groups for each experiment, the elasticity tended to be stronger in most of the higher GA concentration group (porcine pulmonary valve, porcine pericardium). On the thermostability testing of the bovine and porcine pericardium, the GA group and the G+solvent group both had a sudden shrinking point at $80^{\circ}C$ that showed no difference (bovine pericardium: p=0.057, porcine pericardium: p=0.227). Conclusion: When fixing xenograft prosthetic devices with GA, adding a solvent did not cause a loss in pressure-tension, tension-elasticity and thermostability. In addition, more functional solvents or cleansers should be developed for developing better xenografts.

• Journal of Chest Surgery
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• v.41 no.5
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• pp.591-597
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• 2008

Background: Pulmonary endarterectomy is widely accepted as a treatment for chronic thromboembolic pulmonary hypertension. Based on our experiences, we sought to find ways to reduce perioperative complications and to improve surgical outcomes in patients undergoing pulmonary endarterectomy. Material and Method: This study was designed as a retrospective analysis of 20 patients with pulmonary hypertension who underwent pulmonary endarterectomy between January 1998 and March 2008. All patients presented with chronic dyspnea. Deep vein thrombosis (DVT) was the major cause of chronic pulmonary thromboembolism (55%). Seventeen patients (85%) underwent inferior vena cava (IVC) filter placement. Thirteen patients underwent surgery under total circulatory arrest, while the others underwent surgery while on low flow cardiopulmonary bypass. Concomitant tricuspid annuloplasty was done in 6 patients (66%) whose tricuspid regurgitation was as severe as grade IV/IV. The mean follow-up duration was $45{\pm}32$ months. Result: Using of University of California, San Diego (UCSD), thromboembolism classification, 4 patients (20%) were type 1, 8 patients (40%) were type II, and 8 patients (40%) were type III. Right ventricular systolic pressure was reduced significantly from $77{\pm}29$ mmHg to $37{\pm}19$ mmHg after pulmonary endarterectomy (p<0.001). The degree of tricuspid regurgitation and the NYHA functional class were all improved postoperatively. Reperfusion edema occurred in 7 cases (35%). The incidence of reperfusion edema was higher in the UCSD type III group than in the other group (25% vs 50%, p=0.25) and the length of postoperative intensive care unit stay was longer in type III group ($5{\pm}2$ days vs $9{\pm}7$ days, p=0.07). The early mortality rate was 10%, and the late mortality rate was 15% (n=3); one death was due to progression of underlying non-Hodgkin's lymphoma, and the other deaths were related to recurrent thromboembolism and persistent pulmonary hypertension, respectively. Conclusion: Pulmonary endarterectomy, as a curative surgical method for treating chronic thromboernbolic pulmonary hypertension, should be performed aggressively in patients diagnosed with chronic thromboembolic pulmonary hypertension, and an effort should be made to reduce the frequency of perioperative complications and to improve surgical outcomes.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.2
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• pp.136-143
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• 2015

Gotjawal areas have the unique ecosystem and we need to approach as the inhabit of animals to conserve Gotjawal. This study was conducted in Hangyeong-myeon Cheongsu-ri located in the western part of Jeju Island belonging to Hangyeong Andeok Gotjawal Zone and Jocheon-eup Seonheul-ri located in the eastern part of Jeju Island belonging to Jocheon Hamdeok Gotjawal Zone. Survey on advent of the birds was done twice a month from February 2013 to December 2014. A total of 66 species and 4,140 individuals in two Gotjawals were observed during the survey period. In Seonheul Gotjawal area, 53 species and 1,907 individuals were observed while it was 49 species and 2,233 individuals in Cheongsu Gotjawal area. The number of species between two Gotjawal areas was not significantly different, but the number of individuals between two Gotjawal areas was significantly different. Thirty-six species were found in both Gotjawal areas as common species and the index of similarity was 0.7. A total of 23 species were classified as the residents, 15 species as the winter visitors, 16 species as the passage migrants, 11 species as the summer visitors, and 2 species as the vagrant. Twelve species as legally protected birds including the natural monument and the endangered species were found and 8 species were found in Seonheul Gotjawal area while it was 10 species in Cheongsu Gotjawal area. The species that directly using a wetland or food resources related to water were 12 in the Seonheul and 6 species were observed in the Cheongsu Gotjawal area, but there is no significant difference between two Gotjawal areas. However, the number of individuals in Seonheul Gotjawal area was significantly higher than in that of in Cheongsu Gotjawal area. We need to research the wetlands and micro climatic condition existing in Gotjawal forests to find the cause of difference of two areas and this difference must be considered as an important indicator for the protection of Gotjawal forests.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.358-383
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• 2015

The concept of 'carbon footprint' has been developed as a means of quantifying the specific emissions of the greenhouse gases (GHGs) that cause global warming. Although there are still neither clear definitions of the term nor rules for units or the scope of its estimation, it is broadly accepted that the carbon footprint is the total amount of GHGs, expressed as $CO_2$ equivalents, emitted into the atmosphere directly or indirectly at all processes of the production by an individual or organization. According to the ISO/TS 14067, the carbon footprint of a product is calculated by multiplying the units of activity of processes that emit GHGs by emission factor of the processes, and by summing them up. Based on this, 'carbon labelling' system has been implemented in various ways over the world to provide consumers the opportunities of comparison and choice, and to encourage voluntary activities of producers to reduce GHG emissions. In the agricultural sector, as a judgment basis to help purchaser with ethical consumption, 'low-carbon agricultural and livestock products certification' system is expected to have more utilization value. In this process, the 'cradle to gate' approach (which excludes stages for usage and disposal) is mainly used to set the boundaries of the life cycle assessment for agricultural products. The estimation of carbon footprint for the entire agricultural and forestry sector should take both removals and emissions into account in the "National Greenhouse Gas Inventory Report". The carbon accumulation in the biomass of perennial trees in cropland should be considered also to reduce the total GHG emissions. In order to accomplish this, tower-based flux measurements can be used, which provide a direct quantification of $CO_2$ exchange during the entire life cycle. Carbon footprint information can be combined with other indicators to develop more holistic assessment indicators for sustainable agricultural and forestry ecosystems.

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.129-143
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• 1993

The objective of this study is to understand the status of the water pollution in rural areas and to furnish a basic material for the management of the water pollution in rural areas. For this purpose, the Bokha river basin, Ichon-Gun, Kyungki-Do considering as a typical agricultural area was selected as a representative experimental watershed. The characteristics of water pollution in streams of the Bokha river basin was revealed by investigating and analyzing data collected for the source of pollution, water qualities in reaches of the stream, the degree of contribution to the river contamination by pollution mass produced from each source, and the status of the self-purification at the main stream. The most important source of the water pollution in investigated watershed was livestock, and the next important one were in the order of population, land use, and industry. The water quality of the Bokha river was relatively favorable judging from the BOD and COD concentration, however since the concentration of T-N and T-P showed significantly large values, it was concluded that the river was seriously contaminated by the nutrient material. The main cause of the river contamination was proved due to livestock waste. For the T-N, both land use and livestock were much more contributied to the pollution than any other source, which characterized the typical water pollution of rural areas. Run-off ratios for the Bokha river tributaries to the main stream were changed according to the similar trend to the variation of discharges in the branch streams. For the value of the self-purification constant at the main stream, it showed smaller value in the downstream reach than the middle-stream and upstream reaches, where could possibly have smaller reoxidation action due to slower velocity and deeper water depth.

• The Journal of Engineering Geology
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• v.28 no.3
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• pp.411-429
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• 2018

Daeyoung mine (also called "Daema mine") produced gold and silver from mainly gold- and silver-bearing quartz veins. The mine tailings are a waste hazard, but most of the tailings were swept away or dispersed throughout the area around the mine long before the tailing dump areas were transformed into agricultural land. Soil liner and protection facilities, such as retaining walls, were constructed in the mine area to prevent the loss of tailings. The content of the tailings is 3,424.41~3,803.61 mg/kg, which exceeds the safety standard by a factor of 45. In addition, contamination was detected near agricultural areas and in the sediments in downstream drainage channels. A high level of As contamination was concentrated near the waste tailings yard; comparaable levels were detected in agricultural areas close to streams that ran through the waste dump yard, whereas the levels were much lower in areas far from the streams. The contamination in stream sediments showed a gradual decrease with distance from the mine waste yard. Based on these contamination patterns, we concluded that there are two main paths that affect the spread of contaminants: (1) loss of mine waste, and (2) the introduction of mine waste into agricultural areas by floods after transportation by streams. The agricultural areas contaminated by mass inflow of mine waste can act as contamination sources themselves, affecting other agricultural areas through the diffusion of contaminants. At present, although the measured effect in minimal, sediments in streams are contaminated by exposed mine waste and surface liners. It is possible for contaminants to diffuse or spread into nearby areas if heavy elements trapped in soil grains in contaminated agricultural areas leach out as soil solution or contaminant particles during diffusion into the water supply.

• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.16-34
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• 2015

Impervious covers(IC) are artificial structures, such as driveways, sidewalks, building's roofs, and parking lots, through which water cannot infiltrate into the soil. IC is an environmental concern because the pavement materials seal the soil surface, decreasing rainwater infiltration and natural groundwater recharge, and consequently disturb the hydrological cycle in a watershed. Increase of IC in a watershed can cause more frequent flooding, higher flood peaks, groundwater drawdown, dry river, and decline of water quality and ecosystem health. There has been an increased public interest in the institutional adoption of LID(Low Impact Development) and GI(Green Infrastructure) techniques to address the adverse impact of IC. The objectives of this study were to construct the modeling site for a samll urban watershed with the Storm Water Management Model(SWMM), and to evaluate the effect of various LID techniques on the control of rainfall runoff processes and non-point pollutant load. The model was calibrated and validated using the field data collected during two flood events on July 17 and August 11, 2009, respectively, and applied to a complex area, where is consist of apartments, school, roads, park, etc. The LID techniques applied to the impervious area were decentralized rainwater management measures such as pervious cover and green roof. The results showed that the increase of perviousness land cover through LID applications decreases the runoff volume and pollutants loading during flood events. In particular, applications of pervious pavement for parking lots and sidewalk, green roof, and their combinations reduced the total volume of runoff by 15~61 % and non-point pollutant loads by TSS 22~72 %, BOD 23~71 %, COD 22~71 %, TN 15~79 %, TP 9~64 % in the study site.

• Journal of Hospice and Palliative Care
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• v.4 no.2
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• pp.122-129
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• 2001

Purpose : After Acquired Immunodeficiency Syndrome (AIDS) is known to be a fatal disease, efforts and studies are made to determine the cause, treatment method and method of preventing infection. However, no treatment method is present and vaccine development has not been made. Therefore, the most effective treatment method is prevention, and almost 100% prevention is possible when correct preventive measures are taken. We suggest effective prevention education by comparing knowledge and attitude of those unmarried men who had sexual encounters with prostitutes (high risk group) and those with no sexual encounters with prostitutes (low risk group). Methods : From January 1, 2000 to June 30, 2000, a survey was done in 516 unmarried soldiers and college students. With the collected data, chi-square test was used to compare and analyze the demographic characteristic, knowledge on AIDS, and attitude on AIDS between the high risk group and low risk group. One-way ANOVA test was used to compare and analyze the scores on knowledge between these two groups. Results : Among 516 unmarried men, 256 men (49.6%) fell into the high risk group and 260 men (50.4%) into the low risk group. Both groups showed that they heard of AIDS during their middle school years. The main route of obtaining knowledge on AIDS was through TV programs with 124 men(48.4%) in the high risk group and 167 men (64.2%) in the low risk group (P=0.002). Among 20 items, the average score on knowledge was $13.9{\pm}1.9$ in the high risk group and $14.1{\pm}1.8$ in the low risk group with no statistical difference between these two groups (P=0.191). Two items showed statistical significance in the low risk group compared with the high risk group; these were the item of AIDS being transmitted through transfusion (P=0.014) and through mosquitoes (P=0.009). As for attitude, statistical significance was present in the item stating that AIDS patients should be isolated in the high risk group compared with the low risk group (P=0.029). Conclusions : The present study showed that both the high risk group and low risk group obtained knowledge on AIDS through TV. No statistical difference was present between the two groups other than the high risk group showed statistically high results in two items on knowledge and one item on attitude. Thus, these results showed that exposure to AIDS can be lowered with better knowledge and the attitude of those with a low risk of infection was more positive.

• Journal of Korean Medical classics
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• v.13 no.2 s.17
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• pp.174-188
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• 2000

The meaning of Tiangui(天癸) in $Suwen{\cdot}Shanggutianzhenlun\;素問{\cdot}上古天眞論$ is very important because it has the cause of 'having a child' and it shows the signs to being healthy. But until now there have been many arguments about what the correct meaning of Tiangui is. The most important thing in these arguments is to compare and analyze Neijing(內經) commentators' views, and to understand differences between their views. So I compared and analyzed by focusing on Neijing(內經) text, the other books with explanatory notes, and other commentators' views, and, after that. I got the following results. 1. On the meaning of Tian(天), Wangbing(王氷) and Mashi(馬蒔) considered that it is inborn. Zhangjiecong(張志聽) considered it as the Yang(陽) producing Yin(陰) Zhangjiebin(張介賓) regarded it as the Yang(陽) of Gua symbol. On the meaning of the Gui(癸). Zhangjiebin(張介賓) said that it is Yin qi(陰氣) which is the prior step to Xing(形). Mashi(馬蒔) and Zhangzhicong(張志聽) said that it is spirit or Jingxue(spiritual sanguine) which is the concrete constituents in our body. 2. On the relation bet ween Tian(天) and Gui(癸), Mashi(馬蒔) and Zhangzhicong(張志聽) said that Gui(癸) is made from Tian(天), and Zhangjiebin(張介賓) said that Tian is intrinsic in Gui(癸). 3. On the relation between Tiangui(天癸) and Jingxue(精血), Yangshangshan(楊上善). Wangbing(王氷), and Zhangjiebin(張介賓) regarded Tiangui(天癸) as a concrete matter which is the prior step to becoming Jingxue(精血). Mashi(馬蒔) and Zhangjiecong(張志聽) considered Tiangui(天癸) as a concrete matter. Mashi(馬蒔) considered Tiangui(天癸) as Jing(精)which is directly related to pregnancy. Zhangjiecong(張志聽) regarded Tiangui(天癸) as Jingxue(精血) which controls general physiology of men and women. 4. On the function of Tiangui(天癸), Yangshangshan(楊上善) and Wangbing(王氷) considered that Tiangui (天癸) has relation to menstruation. pregnancy. and, production and extinction of Jing(精). Zhangjiecong(張志聽) argued that Tiangui(天癸) strengthens and warms muscle and derma. and controls differential physiology between men and women, and said that the maintenance of its activity is based on the acquired spirit of food. A book of 『Huangti Neijing Yanjiu Dacheng(黃帝內經硏究大成)』 said that the function of Tiangui(天癸) is to promote generation, to develop the second sexual symbol, and to make growing and aging in body. It also said that Tiangui(天癸) has some relation to kidney and other organs, Chong Meridian, Ren Meridian, Du Meridian, and Dai Meridian. 5. Other commentators of 『Neijing(內經)』 accepted the meaning of Tiangui(天癸) as the prior step of both man's spiritual overflowing and woman's menstruation. 6. On the relation between Tiangui(天癸). and, Cheng and Ren Meridians, Yangshangshan(楊上善) and Zhangjiecong(張志聽) said that Tiangui(天癸) has direct relation with two meridians. Wangbing(王氷) said that Tiangui(天癸) and two meridians have no direct relation. Now I compared commentaors' views of Tiangui(天癸) and studied the differences between their views. I concluded that on the concept of Tiangui(天癸), Zhangjiebin(張介賓)'s explanations express well its connotative meaning. And on the function of Tiangui (天癸), Zhangjiecong(張志聽)'s explanations are excellent because he organized well his seniors' views, and extended its meaning by showing Neijing(內經)'s phrases related to Chong and Ren Meridians. Also, Mashi(馬蒔) suggested that if Tiangui(天癸) comes earlier than normal. people will die soon. But I think that more studies on male and female bodies are needed as to Mashi(馬蒔)'s argument.