• Research in Plant Disease
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• v.21 no.2
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• pp.50-57
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• 2015

Control of nematode has become difficult owing to the restricted use of effective soil fumigant, methyl bromide, and other non-fumigant nematicides. Therefore, it is urgently necessary to develop microbial nematicide to replace chemical nematicides. In this study, the 50% aqueous methanol extraction solution of fermentation broths of 2,700 actinomycete strains were tested for their nematicidal activity against second stage of juveniles (J2s) of Meloidogyne incognita. As the results, only the 50% aqueous methanol extraction solution of AN110065, at 20% equivalent to 10% fermentation broth, showed strong nematicidal activity with 78.9% of mortality 24 h after treatment and 94.1% of mortality at 72 h. The 16S rRNA gene sequencing showed that the strain sequence was 99.78% identical to Streptomyces netropsis. The extract of S. netropsis AN110065 fermentation broth was successively partitioned with ethyl acetate and butanol and then the ethyl acetate, butanol and water layers were investigated for their nematicidal activity against the M. incognita. At $1000{\mu}g/ml$, ethyl acetate layer showed the strongest activity of 83.5% of juvenile mortality 72 h after treatment. The pot experiment using the fermentation broth of AN110065 on tomato plant against M. incognita displayed that it evidently suppressed gall formation at a 10-fold diluent treatment. The tomato plants treated with the fermentation broth of S. netropsis AN110065 did not show any phytotoxicity. The results suggest that S. netropsis AN110065 has a potential to serve as microbial nematicide in organic agriculture.

• Journal of Chest Surgery
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• v.39 no.3 s.260
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• pp.208-213
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• 2006

Background: The prevalence of anastomotic complication is related to anastomotic procedure or site in esophageal cancer operation. We studied the anastomotic leakage and stricture related to the anastomotic procedure & site in patients who received the esophageal resection and reconstruction for esophageal cancer. Material and Method: The anastomotic procedure, site and complication of 321 patients who received the esophageal reconstruction from August 1993 to May 2003 were investigated. Mean age was 64.5$\pm$4.9 (37${\~}$94) years, 300 patients ($93.5\%$) were male and 21 patients were female ($6.5\%$). Result: There were 7 anastomotic leakages ($2.2\%$) and no difference in anastomotic site (cervical anastomosis $4.1\%$, thoracic anastomosis $1.6\%$) and procedure (stapler technique $1.6\%$, semi-staple technique $9.1\%$, hand-sewn technique $0.0\%$). There were 52 anastomotic strictures ($16.2\%$), differences in sites (cervical anastomosis $2.7\%$, thoracic anastomosis $20.2\%$) (p < 0.001) and procedure (stapler technique $20.0\%$, semi-stapler technique $3.0\%$, hand-sewn technique $4.7\%$). And the stapler technique showed higher stricture rate (p < 0.001). Conclusion: Anastomotic technique was less related to anastomotic leakage in esophageal reconstruction for esophageal cancer. However, stapler technique had higher stricture rate than other techniques. Therefore, we suggest that the anastomotic technique be improved to reduce anastomotic stricture.

• Journal of Chest Surgery
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• v.38 no.6 s.251
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• pp.403-409
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• 2005

Pulmonary atresia with intact ventricular septum is morphologically heterogeneous, and the surgical outcome remains suboptimal compared to other complex congenital heart defects. We evaluated the long-term results for repair of pulmonary atresia with intact ventricular septum, Material and Method: Between January 1992 and June 2004, 38 patients underwent repair of pulmonary atresia with intact ventricular septum. The average age was 18 days $(2\~382\;days)$. The average Z-value of the tricuspid annulus diameter was -3.1$(-5.6\~0.8)$. Thirteen $(36\%)$ patients had right ventricle-to-coronary artery fistulas, and $4(11\%)$ patients had right ventricle-dependent coronary circulation. Average follow-up was 55 months $(3\;months\~2.2\;years)$, Result: Twenty-four patients under-went initial right ventricle (RV) decompression and 14 patients underwent systemic-to-pulmonary arterial shunt only. The average size of the tricuspid annulus of the patients who underwent RV decompression was significantly larger than that of the patients who underwent systemic-to-pulmonary arierial shunt only (Z-value -2.2 vs. -4.8, p=0.000). There were $5(13\%)$ early and 1 late deaths. Early deaths occurred in 3 patients who had undergone RV decompression, and in 2 patients who had undergone systemic-to-pulmonary arterial shunt only (p=1.0). Biventricular repair was achieved in $12(32\%)$ patients, single ventricular repair in $8(21\%)$, and one and a half ventricular repair in $4(l1\%)$ patients. Nine $(24\%)$ patients are waiting for the definitive repair. Kaplan-Meier survival at 5 and 8 years was $83.2\%$, respectively. Conclusion: Most of the deaths occurred after the initial palliation. Overall long-term survival was satisfactory. Early mortality should be reduced with careful preoperative evaluation and proper surgical strategy.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.806-812
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• 1999

Background: Selection of reconstruction route in esophageal cancer surgery is based on the patient's status, characteristics of tumor, surgeon's preference and experience. Of the various routes, it has been documented that subcutaneous or substernal route may prolong operation time and may be vulnerable to postoperative respiratory complications. This study was designed to evaluate whether the selection of reconstruction route affects the surgical outcomes. Material and Method: Of 131 patients who have undergone resection and reconstruction for esophageal cancer, posterior mediastinal route(Group I, n=34), substernal route (Group II, n=31), and subcutaneous route(Group III, n=21) were retrospectively reviewed in 86 patients. Results of early operations and morbidities were compared between the groups. Result: There was a male prevalence(79 of males vs. 7 of females). There were 81 squamous cell cancers and 5 adenocarcinomas. There were no differences between groups in weight, height, age, cancer staging and location, and in the preoperative anesthetic risk evaluation and pulmonary function test(p=NS). Postoperative mechanical ventilation time was longer in Group I(20.6 hours) than in Group II(7.8 hours) or III(3.4 hours)(p=0.005). Duration of stay in the intensive care unit was prolonged in Group III(6.4 days) compared to Group I (3.9 days) or II(3.1 days)(p=0.043). No differences were noted in the duration of hospital stay between the groups(p=NS). Blood transfusion was needed in 30 out of 34 patients in Group I compared to 14/31 in Group II or 15/21 in Group III(p=0.001). The mean amount of transfusion for each patient was also higher in Group I(3,833 mL) than in Group II(1535 mL) or Group III(1419 mL)(p=0.04), but there was no difference in the inreoperation due to bleeding. Ea ly mortality rate was substantially higher in Group I(17.6%) but the differences between the groups were insignificant(p=NS). Although sepsis was a more prevalent cause of death in Group I, it was not related to anastomotic leak. Other morbidities did not differ between the groups(p=NS). Conclusion: In above results show that the reconstruction route does not affect the outcome of esophageal cancer surgery. We believe that the selection of reconstruction route can be based on the surgeon's preference and experience.

• Journal of Chest Surgery
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• v.30 no.6
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• pp.591-597
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• 1997

Cardiopulmonary bypass in children is associated with capillary leak which results in an increase in total body water after open heart surgery The purpose of these studies was to assess the cardiopulmonary effects of modified ultrafiltration after pediatric open heart surgery Study h: Twenty-six consecutive children aged 0.1 ~ 10 years(median 7 months) underwent cardiac operation inc rporating modified ultrafiltration. After completion of cardiopulmonary bypass, modified ultrafiltration was commenced at the flow rate of 100~ 15011min for 3 ~ 14 min. After modified ultrafiltration, elevation of hematocrit(28.3% $\pm$ 3.6% vs. 33.8olo $\pm$ 4.Ooloi p < 0.001), increased systolic 1)loots Pressure(66.7 $\pm$ 11.2mmHg vs. 76.2$\pm$ 11.BmmHg, p < 0.02), and decreased central venous pressure(7.8 $\pm$ 3.7mmHg vs. 6.9$\pm$ 2.gmmHg, p<0.001) were observed. Study B: Twenty-six children who underwent cardiac operation with the diagnosis of VSD under 2 years were assigned to control(n= 14) or modified ultrafiltration(n= 12). Peak inspiratory pressure checked immediately after operation was significantly lower in modified ultrafiltration group than in control group(20.0$\pm$ 2.4 cmH20 vs.22.4$\pm$ 2.3cmH20, p < 0.03). Modified ultrafiltration after cardiopillmonary bypass in children improves early homodynamics and pulmonary mechanics, and represents an excellent option for perioperative managemen of accumulation of fluid in the tissues. We will continually employ the modified ultrafiltration technique in pediatric cardiac operations.

• Journal of Chest Surgery
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• v.40 no.6 s.275
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• pp.399-406
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• 2007

Background: Ischemia-reperfusion injury related to unsuccessful myocardial protection affects postoperative ventricular function and mortality during open-heart surgery. We prospectively compared the effects of administration of histidine-tryptophan-ketoglutarate (HTK) solution and cold blood cardioplegia (CBC) on myocardial protection and clinical outcome in patients undergoing mitral valve surgery. Material and Method: Seventy patients with mitral regurgitation (MR) undergoing mitral valve surgery were randomly divided into the HTK group (n=31) and the CBC group (n=31 ): eight patients were excluded. Perioperative hemodynamics, cardiac medications, pacing, postoperative outcomes and complications were recorded during the hospital stay. All patients received follow-up for at least 6 months postoperatively for morbidity and mortality. Resuか: There were no significant differences in the hemodynamics between the groups during the study period, except for the mean pulmonary artery pressure (MPAP), PCWP and CVP that were lower in the HTK group at 15 min after weaning of CBP. There were no differences for inotropic support and pacing during the 12 hrs postoperatively between the groups. CK-MB values on day 1 and day 2 were $77{\pm}54$ and $41{\pm}23$ for the HTK group and $70{\pm}69$ and $44{\pm}34$ for the CBC group, respectively (p=NS). Postoperative clinical outcomes were similar in both groups for at least 6 months during the follow-up period. Conclusion: These results suggest that the use of HTK solution is as safe as cold blood cardioplegia in terms of myocardial protection.

• Journal of Chest Surgery
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• v.40 no.2 s.271
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• pp.83-89
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• 2007

Background: The surgical repair of an isolated coarctation of the aorta, without complex cardiac anomalies, has improved, with very good results. However, despite the success of surgical repair, many long-term complications, such as hypertension, re-coarctation and an aortic aneurysm, still exist. Material and Method: Between 1991 and 2006, 50 patients diagnosed with an isolated coarctation of the aorta were reviewed retrospectively. The incidence of re-coarctation and hypertension were compared with respect to age and surgical methods. Result: There were no early & late mortality, or post operative aortic aneurysms. Hypertension developed in 11 patients (22%). A greater number of patients in the child/adult group had hypertension (52.4%) than in the neonate/infant group (0%). With respect to the surgical methods, the patients in the graft interposition group suffered more hypertension (88.9%) than those in the EEEA (extended end to end anastomosis) group (5.3%). Post operative re-coarctation developed in 2 out of the 29 patients (6.9%) in the neonate/infant group and 2 out of the 21 patients (9.5%) in the child/adult group, but without any statistical difference. There were no statistical differences between the operative type-related groups. Conclusion: Even though the surgical outcomes have greatly improved, an isolated coarctation of the aorta still has many long-term problems, such as hypertension and re-coarctation. An isolated coarctation is accepted as a systemic vascular dysfunction, and often progresses to other cardiovascular diseases. Therefore, patients with a coarctation of the aorta have to be carefully followed-up, and aggressive management must be given when required.

• Journal of Korea Water Resources Association
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• v.51 no.1
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• pp.11-18
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• 2018

The climate change impacts on hydrological components and water balance in Jeju Island were evaluated using multiple climate models and watershed model, SWAT-K. To take into account the uncertainty of the future forecast data according to climate models, climate data of 9 GCMs were utilized as weather data of SWAT-K for future period (2010-2099). Using the modeling results of the past (1992-2013) and the future period, the hydrological changes of each year were analyzed and the precipitation, runoff, evapotranspiration and recharge were increasing. Compared with the past, the change in the runoff was the largest (up to 50% increase) and the evapotranspiration was relatively small (up to 11% increase). Monthly results show that the amount of evapotranspiration and the amount of recharge are greatly increased as the amount of precipitation increases in August and September, while the amount of evapotranspiration decreases in the same period. January and December showed the opposite tendency. As a result of analyzing future water balance changes, the ratio of runoff, evapotranspiration, and recharge to rainfall did not change much, but compared to the past, the runoff rate increased up to 4.3% in the RCP 8.5 scenario, while the evapotranspiration rate decreased by up to 3.5%. Based on the results of other researchers and this study, it is expected that rainfall and runoff will increase gradually in the future under the assumption of present climate change scenarios. Especially summer precipitation and runoff are expected to increase. As a result, the amount of groundwater recharge in Jeju Island will increase.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.71-78
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• 2000

Preferential flow has recently been the subject of increasing interest because these phenomena contribute to solute transport in soils. Commonly, preferential flow paths are associated with macropores or highly structured soils. We presented an analysis of the measured breakthrough curves (BTCs) of $Cl^-$ and $Cu^{2+}$ ions to test the occurrence of preferential flow in soils using miscible displacement technique under steady flow conditions. We also analyzed soil water retention curves and from this curves induced cumulative pore size distribution of undisturbed soils, which sampled from Ap1, B1, and C horizons of Songjeong series soils (the fine loamy, mesic family of Typic Hapludults). In this study, miscible displacement experiment on C horizon was excluded, because it is structureless sandy loam with saturated hydraulic conductivity of $5.2cmhr^{-1}$. The saturated hydraulic conductivity of Ap1 horizon was $2.0cmhr^{-1}$, which was about 7 times higher than that of B1 horizon ($0.27cm hr^{-1}$). Cumulative pore size distribution predicted that Ap1 horizon had more macropores (pore diameter larger than $49{\mu}m$, equivalent to -6 kpa of soil matric potential) than B1 horizon. The hydrodynamic dispersion coefficient from chloride BTCs was estimated as $1.3cm^2hr^{-1}$ for B1 and $34cm^2hr^{-1}$ for Ap1 horizon. However the retardation factors of B1 and Ap1 horizon were significantly different, i.e. 1 and 0.6, respectively, which means that there was distinct partition between mobile water and immobile phase in Ap1 horizon. The copper retardation effect of Ap1 horizon was less than that of B1 horizon, even though cation exchange capacity of Ap1 horizon was higher than that of B1 horizon. Thus, breakthrough curves of $Cl^-$ and $Cu^{2+}$ obviously showed the probability that preferential flow would occur in Ap1 horizon.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.274-279
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• 2006

The exact estimation of crop evapotranspiration containing reference or potential evapotranspiration is necessary for decision of crop water requirements. This study was carried out for the evaluation and application of various meteorological elements used for the calculation of reference evapotranspiration (RET) by FAO Penman-Monteith (PM) model. Meteorological elements including temperature, net radiation, soil heat flux, albedo, relative humidity, wind speed measured by meteorological instruments are required for RET calculation by FAO PM model. The average of albedo measured for crop growing period was 0.20, ranging from 0.12 to 0.23, and was slightly lower than 0.23. Determinant coefficients by measured albedo and green grass albedo were 0.97, 0.95 and standard errors were 0.74, 0.80 respectively. Usefulness of deductive regression models was admitted. To assess an influence of soil heat flux (G) on FAO PM, RET with G=0 was compared with RETs using G at 5cm soil depth ($G_{5cm}$) and G at surface ($G_{0cm}$). As the results, RET estimated by G=0 was well agreed with RET calculated by measured G. Therefore, estimated net radiation, G=0 and albedo of green grass could be used for RET calculation by FAO PM.