• Korean Journal of Environment and Ecology
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• v.32 no.5
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• pp.469-477
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• 2018

Hanabusaya asiatica is an endemic species whose distribution is limited in the mid-eastern part of the Korean peninsula. Due to its narrow range and small population, it is necessary to protect its habitats by identifying it as Key Biodiversity Areas (KBAs) adopted by the International Union for Conservation of Nature (IUCN). In this paper, we estimated potential natural habitats for H. asiatica using maximum entropy model (MaxEnt) and identified candidate sites for KBA based on the model results. MaxEnt is a machine learning algorithm that can predict habitats for species of interest unbiasedly with presence-only data. This property is particularly useful for the study area where data collection via a field survey is unavailable. We trained MaxEnt using 38 locations of H. asiatica and 11 environmental variables that measured climate, topography, and vegetation status of the study area which encompassed all locations of the border region between South and North Korea. Results showed that the potential habitats where the occurrence probabilities of H. asiatica exceeded 0.5 were $778km^2$, and the KBA candidate area identified by taking into account existing protected areas was $1,321km^2$. Of 11 environmental variables, elevation, annual average precipitation, average precipitation in growing seasons, and the average temperature in the coldest month had impacts on habitat selection, indicating that H. asiatica prefers cool regions at a relatively high elevation. These results can be used not only for identifying KBAs but also for the reference to a protection plan for H. asiatica in preparation of Korean reunification and climate change.

• Environmental and Resource Economics Review
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• v.23 no.4
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• pp.719-746
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• 2014

This study attempts to estimate the value of the water quality improvement by deriving the equilibrium price of the water pollutant emission permit for the imaginary water pollutant emission trading market. It is reasonable to say that there is already an implicit social agreement for the unit value of water pollutant, when the government set the Total Water Pollutant Loading System for the major river basin as a part of the Comprehensive Measures for Water Management, particularly for the Nakdong River Basin. Therefore, we can derive the unit value of water pollutant emission, which is already implied in the pollution allowance for each city or county by the Total Water Pollutant Loading System. Once estimated, it will be useful to the economic assessment of the water quality related projects. An imaginary water pollutant emission trading system for the Nakdong River Basin, where Total Water Pollutant Loading System is already effective, is constructed for the estimation of the equilibrium price of water pollutant permit. By estimating marginal abatement cost curve or each city or county, we can compute the equilibrium price of the permit and then it is regarded as the economic value of the water pollutant. The marginal net benefit function results from the relationship between the emission and the benefit, and then the equilibrium price of permit comes from constructing the excess demand function of the permit by using the total allowable permit of the local government entity. The equilibrium price of the permit would be estimated to be $1,409.3won/kg{\cdot}BOD$. This is within reasonable boundary compared for the permit price compared to foreign example. This permit price would be applied to calculate for the economic value of the water quality pollutants, and also be expected to use directly for the B/C analysis of the business involved with water quality change.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.275-282
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• 2018

Miscanthus species are known as a genus of eco-friendly and low-maintenance cost ornamental grasses. Plug and cutting methods were tested for multi-propagation of most promising ornamental Miscanthus species in greenhouse and field plot. The plug formation period with three different cell sizes with four cultivars (M. sinensis 'Andersson', 'Strictus', 'Gracillimus', 'Variegatus') were evaluated the seedling development stages with two irrigation types of the over-head and the bottom watering in greenhouse and field plot afterward during 2015-2016 season. In seedling plug test, the size of tray cell affected the plug formation. Bottom irrigation resulted positively on plant height, weight, root and tiller development compared with the over-head irrigation. Plug cell size affected the plant growth in the field after transplanting. All of the 3 Miscanthus species showed higher rates of successful propagation at the lower nodes before inflorescence formation (vegetative growth stage). To analyze the survival factors of M. xgiganteus cutting, the cutting time, node part, and culm diameter were tested as independent variables with the binary logistic model. The survival probability was influenced by node part and culm diameter significantly. The third and fifth node parts showed 0.12 (8X higher failure probability) and 0.02 (50X higher failure probability) times less survival probability. It means the survival probability will be increased by using older and lower part of cuttings during a vegetative growth stage before inflorescences of M. xgiganteus.

• Journal of the Korean Wood Science and Technology
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• v.34 no.4
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• pp.37-45
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• 2006

Recently, wood-framed houses has been built in the Korea for pension. Wood is good material for human healthy, while the construction lumbers are treated with preservative such as CCA (chromated copper arsenate), which contain some toxic elements for human body. However, if the waste woody biomass treated with various heavy metals, which has been collected from house construction or demolition, was fired in the field, and incinerated or landfilled after mass collection, such components will result in the toxic air pollutants in the burning or land fills, and spreaded into other areas. So the careful selection of wood and chemicals are required in advance for house construction, in particular, for environment-friendly housings. Therefore, this study was carried out to determine the content of toxic heavy metals in woody materials such as domestic hinoki and imported hemlock treated with CCA for housing materials, and the post-treated wood components such as organic fertilizer, sludge, dry-distilled charcoal and carbonized charcoal, to be returned finally into soil. The results are as follows. 1) The chemical analysis of toxic trace elements in various solid biomass required accurate control and management of laboratory environment, and reagents and water used, because of the error of data due to various foreign substances added in various processing and transporting steps. So a systematic analyzers was necessary to monitor the toxic pollutants of construction materials. 2) In particular, the biomass treated with industrial biological or thermal conditions such as sludge or charcoals was not fully dissolvable after third addition of $HNO_3$ and HF. 3) The natural woody materials such as organic fertilizer, sludge. and charcoals without any treatment of preservatives or heavy metal components were nontoxic in landfill because of the standard of organic fertilizers, even after thermal or biological treatments. 4) The CC A-treated wood for making the construction wood durable should not be landfilled, because of its higher contents of toxic metals than the criterion of organic fertilizer for agriculture or of natural environment. So the demolished waste should be treated separately from municipal wastes.

• Sleep Medicine and Psychophysiology
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• v.7 no.1
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• pp.43-50
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• 2000

Objectives: Obstructive sleep apnea syndrome(OSAS) is known to be associated with the changes of autonomic nervous system (ANS). Nasal continuous positive airway pressure(nCPAP) treatment was found to correct abnormal ANS changes in OSAS but it remains to be further clarified. We aimed to assess the effects of nCPAP on ANS manifested on electrocardiogram, using spectrum analysis in the subjects with OSAS. Methods: Digital polysomnography was performed in 18 patients with OSAS(mean age $43.7{\pm}16.6$ years ; 17 males, 1 female ; mean respiratory disturbance index (RDI) $48.6{\pm}20.9$) for one baseline and another CPAP nights. From each night, 300 continuous beats of ECGs without artifact were chosen from both stage 2 sleep and REM sleep and they were used for power spectrum analysis. We compared between baseline and CPAP nights the heart rate variability including VLF(very low frequency power), LF (low frequency power), HF(high frequency power), R-R means, R-R variance, and LF/HF ratio, using Wilcoxon signed ranks test. Results: In all patients, nCPAP proved to be effective in relieving apneas and snoring. During nCPAP night compared with baseline night, decreases in VLF(p<0.05), LF(p<0.01), and R-R variance(p<0.05) were found in stage 2 sleep, and decreased LF(p<0.05) was found in REM sleep. No significant differences in each sleep stage were found in other variables between the two nights. Conclusion: Our findings suggest that OSAS increases the activity of sympathetic nervous system and nCPAP application effectively decreases the activity. And nCPAP does not appear to influence the parasympathetic nervous activity in OSAS.

• Journal of Yeungnam Medical Science
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• v.1 no.1
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• pp.67-87
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• 1984

The earliest memories and dreams have been investigated in many aspects; biological, psychological, statistical, and psychotherapeutic, in psychiatric field. The approach methods to these psychic contents are innumerable according to the schools, the collector's attitudes to these materials, the collecting methods and the variable factors of the reporter. In this study the author attempted to compare the distribution of the aggression and dependency themes in these psychic contents among groups of different sexes and clinical diagnoses. In this purpose the author devised new scales, the Aggression and the Dependency Scales for the earliest memories and dreams which are composed of 12-theme classes, according to 3 aspects of the ego attitudes and 4 degrees of the intensity of drives. The scales were tested on a series of the earliest memories and dreams from 100 male medical students by two raters. The interrater reliabilities, measured by kappa method, were all significant at better than the .001 level. The author collected the reports of the earliest memories and dreams from 293 schizophrenics (161 males and 132 females) and 301 neurotics (164 males and 137 females) who were either outpatients or inpatients of 5 general hospitals and 2 private neurospychiatric clinics and from 310 controls (169 males and 141 females) who were either students, housewives or employees in Taegu area during the periods from March to August, 1980 and from April to August, 1983. The author compared the contents of the earliest memories and dreams from these 3 clinical groups on the newly devised scales and the results could be summarized as follows: In general, the contents of the earliest memories showed more differences among diagnostically different groups, while the contents of dreams showed more differences among sexually different groups. The dependency themes were more frequent than the aggression thems in all groups. The aggression themes were more frequent in dreams than in the earliest memories. Of the earliest memory themes, the distribution of the aggression themes was different among clinical groups, i.e., most frequent in schizophrenics, next in neurotics, and least in controls. The distribution of the dependency themes was in reverse order. Attitudes of being attacked were more frequent in schizophrenics. Observing attitudes of dependency need were more frequent in neurotics while gratifying attitudes were more frequent in controls. Highest degrees of aggression and delpendency were more frequent in neurotics. In the distribution of the dream themes, there were some differences among male and female schizophrenics. Aggression themes, especially active and the highest degree of aggression, were more frequent in male sclizophrenics, while dependency themes, especially frustrated themes, were more frequent in female schizophrenics. Among 3 clinical groups, observing attitudes of dependency need were more frequent in female groups, while gratifying attitudes were more frequent in male groups.

• Journal of agricultural medicine and community health
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• v.41 no.4
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• pp.205-216
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• 2016

Objectives: We compared the difference of lipid, insulin resistance and metabolic markers based on HCV RNA in Korean adults.Methods: This was a cross-sectional study of 222 subjects visited the health promotion center of Pusan nationaluniversity hospital from 2004 to 2007. Subjects were anti-HCV antibody positive and were performed RT-PCR for HCV RNA. The HCV RNA (+) group were 85 subjects, HCV RNA (-) control group were 115 subjects, and the HCV RNA (-) but past positive group were 22 subjects. We performed anthropometry, anti-HCV, RT-PCR, plasma concentrations of insulin, total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglyceride.Results: BMI, waist circumference, blood pressure, fasting plasma glucose, triglyceride, HDL cholesterol, insulin resistance such as HOMA-IR and QUICKI were not significantly different between HCV RNA positive and negative groups. The serum total cholesterol and LDL cholesterol level were significantly lower in the HCV RNA positive group than in the negative group ($186.24{\pm}37.63$ vs $197.22{\pm}37.23$ mg/dl, p=0.041, $111.66{\pm}34.06$ vs $121.38{\pm}35.50$ mg/dl, p=0.042). After adjusting age and sex, high total cholesterol (${\geq}200mg/dl$) (adjusted OR=0.51, 95%CI 0.28-0.94, p=0.03) and high LDL cholesterol (${\geq}130mg/dl$) (adjusted OR=0.46, 95%CI 0.24~0.87, p=0.02) were inversely associated with being HCV RNA positive (p<0.05). Conclusion: The serum total cholesterol and LDL-cholesterol level were significantly lower in HCV RNA (+) group than in HCV RNA (-) group, but not in HCV RNA (-) but past positive group. Prospective cohort studies are needed to clarify the relationship between HCV RNA and metabolic markers.

• Journal of Chest Surgery
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• v.36 no.11
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• pp.820-827
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• 2003

Background: Mitral valve repair rather than replacement for mitral regurgitation (MR) offers a number of well-accepted benefits. However, the surgical results of repair for mitral valve endocarditis remain largely unknown. Material and Method: Fourteen patients who underwent mitral valve repair for MR caused by mitral valve endocarditis from April 1995 through October 2001 were reviewed retrospectively. There were 9 male patients and mean age was 32$\pm$10 years. Four patients had previous embolism and 2 had active infections. The grade of MR were III in 6 patients and IV in 8. Operatively, mitral annuloplasty was performed in 12 patients and various valvuloplasty techniques were applied in all patients. One patient had immediate valve replacement due to residual MR after weaning of cardiopulmonary bypass. Result: There was no early operative death. Early postoperative transthoracic echocardiography revealed no or grade I of MR and no or mild mitral stenosis in 13 patients. After the mean follow-up of 36 months, there was no late death, and no or grade I of MR in 11 patients (84.6%) and no or mild mitral stenosis in 12 patients (92.3%). Reoperation required in one patient (7.1%). The cumulative freedom from recurrent MR and valve-related reoperation at 5 years were 91$\pm$9% and 75$\pm$22%, respectively. Conclusion: This study suggests that mitral valve repair for mitral regurgitation caused by endocarditis offers good early and intermediate survival and functional improvement without reinfection, and it is an attractive alternative to valve replacement in selective patients with bacterial endocariditis.

• Food Science of Animal Resources
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• v.28 no.1
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• pp.45-50
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• 2008

This study was conducted to investigate the effect of different maturity scores [2 (bull), 2 (steer), 3-9 (cow)] and the number of extractions on water extract from Hanwoo shank bones (arm, fore shank, round and hind shank) with regard to sensory traits (white color, aroma, taste, overall acceptability). The white color of water extract from Hanwoo shank bones of maturity score 2 (bull and steer) was lighter than with maturity scores of 3-9 (cow) (p<0.05). The aroma of water extract from Hanwoo shank bones of maturity score 2 (bull and steer) was stronger than with other maturity scores 3-9 (cow) except for maturity score 5 (p<0.05). The taste and overall acceptability of water extract from Hanwoo shank bones of maturity score 2 (bull and steer) were higher than with maturity scores of 3-9 (cow) (p<0.05). The white color, aroma, taste and overall acceptability of water extract from Hanwoo shank bones of all maturity scores significantly decreased as the number of extractions (from 2nd to 4th) increased (p<0.05). In conclusion, there were significant differences between maturity scores 2 and maturity scores 3-9 (cow) with regard to sensory traits. Further studies need to address whether different maturity scores affect the price of shank bones in the meat industry.

• Journal of Chest Surgery
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• v.36 no.11
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• pp.812-819
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• 2003

Background: Left ventricular dysfunction is one of the important prognostic factors of early mortality and long-term survival after valve operation. We studied the intermediate term results of mitral valve reconstruction in patients with moderate to severe left ventricular dysfunction. Material and Method: Forty four patients who underwent mitral valve reconstruction with a left ventricular ejection fraction (EF) of <45% or less (20∼45%) from April 1995 through July 2001 were reviewed retrospectively. Ages ranged from 10 to 67 years (46∼14 years) and 32 patients were in NYHA class III-IV. The mitral valve diseases were regurgitation (MR) in 28 patients, stenosis(MS) in 10, and mixed lesion in 5. The etiologies of mitral valve disease were rheumatic in 20 patients, degenerative in 14, ischemic in 5, annular dilatation in 2, congenital in 2, and endocarditis in 1. Operatively, all patients had annuloplasty and/or various valvuloplasty techniques, and a total of 52 procedures were concomitantly performed. Total cardiopulmonary bypass and aortic crossclamp time were 160$\pm$57 minutes and 112$\pm$45 minutes respectively. Result: Two operative deaths occurred as a result of left ventricular failure (4.5%). After the mean follow-up of 39 months (range, 10∼83 months), there was no late death. Transthoracic echocardiography revealed no or grade I of MR in 29 patients (72.5%) and no or mild MS in 35 patients (87.5%). The actuarial survival at 5 years was 100%. Four patients required mitral valve replacement due to progressive mitral valvular disease. The actuarial freedom from valve-related reoperation at 5 years was 84$\pm$9%. Conclusion: This study suggests that mitral valve reconstruction in patients with moderate to severe left ventricular dysfunction offers good early and intermediate survival and acceptable freedom from valve-related reoperation, and it is the strategy for effective management for these patients.