• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.1
• /
• pp.14-21
• /
• 1997

This experiment was conducted to identify the growth and yield differences in rice cultural types: Broadcasting on flooded paddy surface(BF), drilling on flooded paddy surface(DF), puddled-soil drill seeding(PD), drill seeding on dried paddy flat(DD), and machine transplanting of lO-day old seedling(MT) at National Honam Agricultural Experiment Station in 1995. Among the cultural types of direct seeding, the number of seedling stand showed high in order of DD>BF>DF>PD. Tillering at early growth stage was faster in MT and effective tiller showed higher in MT than in direct seeding. Growth duration from seeding to heading was longer in direct seeding than in MT for 2-13 days of Dongjinbyeo and 10-18 days of Nonganbyeo. Root distribution ratio at the surface soil revealed high in order of BF>DF>PD>DD and MT. Culm wall thickness of 4th internode was thicker in machine transplanting of 10-day old seedling than in direct seeding, and the depth of buried culm showed deep by turns of MT> DD>PD>DF and BF. The height of center gravity and moment related to lodging revealed higher in direct seeding than machine transplanting that resulted high lodging index by turns of BF>DF>DD> PD among the direct seeding cultural type. Lodging was occured seriously in the order of BF>DF>PD>DD =MT in Dongjinbyeo but wasn't significantly different in Nonganbyeo among the cultural type. The yield components and grain yield showed varietal differences but was not significantly different between in MT and in direct seeding, and among cultural types of direct seeding.

• Journal of Chest Surgery
• /
• v.56 no.4
• /
• pp.274-281
• /
• 2023

Background: Patients who require initial venoarterial extracorporeal membrane oxygenation (VA ECMO) support may need to undergo veno-arteriovenous ECMO (VAV ECMO) conversion. However, there are no definitive criteria for conversion to VAV ECMO. We report 9 cases of VAV ECMO at Gyeongsang National University Changwon Hospital, Gyeongsang National University College of Medicine. Methods: Of 158 patients who received ECMO support between January 2017 and June 2019, 82 were supported by initial VA ECMO. We retrospectively reviewed the medical records of 9 patients (7 men and 2 women; age, 53.1±19.4 years) who had differential hypoxia and required VAV ECMO support. Percutaneous transaortic catheter venting was used to detect the differential hypoxia. Results: Among the 82 patients who received VA ECMO support, 9 (10.9%) had differential hypoxia and required conversion to VAV ECMO support. The mean time from VA ECMO support to VAV ECMO support and the mean duration of the VAV support were 2.1±2.2 days and 1.9±1.5 days, respectively. The average peak inspiratory pressure before and after VAV ECMO application was 23.89±3.95 cmH₂O and 20.67±5.72 cmH₂O, respectively, decreasing by an average of 3.2±3.5 cmH₂O (p=0.040). The PaO₂/FiO₂ ratio was kept below 100 mm Hg in survivors and non-survivors for 116±65.4 and 250±124.9 minutes, respectively (p=0.016). Six patients underwent extracorporeal cardiopulmonary resuscitation, of whom 4 survived (67%). The overall survival rate of patients who underwent conversion from VA ECMO to VAV ECMO was approximately 56%. Conclusion: Rapid detection of differential hypoxia is required when VA ECMO is applied, and efficient conversion to VAV ECMO may be critical for patient survival.

• Safety and Health at Work
• /
• v.14 no.2
• /
• pp.141-152
• /
• 2023

Objective: We performed a meta-analysis of epidemiological results for the association between occupational exposure as a firefighter and cancer as part of the broader evidence synthesis work of the IARC Monographs program. Methods: A systematic literature search was conducted to identify cohort studies of firefighters followed for cancer incidence and mortality. Studies were evaluated for the influence of key biases on results. Random-effects meta-analysis models were used to estimate the association between ever-employment and duration of employment as a firefighter and risk of 12 selected cancers. The impact of bias was explored in sensitivity analyses. Results: Among the 16 included cancer incidence studies, the estimated meta-rate ratio, 95% confidence interval (CI), and heterogeneity statistic (I²) for ever-employment as a career firefighter compared mostly to general populations were 1.58 (1.14-2.20, 8%) for mesothelioma, 1.16 (1.08-1.26, 0%) for bladder cancer, 1.21 (1.12-1.32, 81%) for prostate cancer, 1.37 (1.03-1.82, 56%) for testicular cancer, 1.19 (1.07-1.32, 37%) for colon cancer, 1.36 (1.15-1.62, 83%) for melanoma, 1.12 (1.01-1.25, 0%) for non-Hodgkin lymphoma, 1.28 (1.02-1.61, 40%) for thyroid cancer, and 1.09 (0.92-1.29, 55%) for kidney cancer. Ever-employment as a firefighter was not positively associated with lung, nervous system, or stomach cancer. Results for mesothelioma and bladder cancer exhibited low heterogeneity and were largely robust across sensitivity analyses. Conclusions: There is epidemiological evidence to support a causal relationship between occupational exposure as a firefighter and certain cancers. Challenges persist in the body of evidence related to the quality of exposure assessment, confounding, and medical surveillance bias.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.11 no.3
• /
• pp.184-191
• /
• 2023

With increasing corrosion in RC (Reinforced Concrete) structures, cracks occurred due to corrosion products and bearing load resistance decreased. In this study, corrosion was induced through an accelerated corrosion test (ICM: Impressed Current Method) with 140 hours of duration, and changes in USV (Ultra-Sonic Velocity), flexural failure load, and corrosion weight were evaluated before and after corrosion test. Three levels of cover depth (20 mm, 30 mm, and 40 mm) were considered, and the initial cracking period increased and the rust around steel decreased with increasing cover depth. In addition, the USV linearly decreased with decreasing cover depth and increasing amount of corrosion. In the flexural loading test, the bending capacity decreased by more than 10% due to corrosion, but a clear correlation could not be obtained since the corrosion ratio was small, so that the effect of slip was greater than that of reduced cross-sectional area of steel due to corrosion. As cover depth increased, the produced corrosion amount and USV changed with a clear linear relationship, and the cracking period due to corrosion could be estimated by the gradient of the measured corrosion current.

• Korean Journal of Radiology
• /
• v.22 no.8
• /
• pp.1253-1265
• /
• 2021

Objective: To investigate the prognostic value of preoperative cardiac magnetic resonance imaging (MRI) for long-term major adverse cardiac and cerebrovascular events (MACCEs) in patients undergoing tricuspid valve (TV) surgery for functional tricuspid regurgitation (TR). Materials and Methods: The preoperative cardiac MR images, New York Heart Association functional class, comorbidities, and clinical events of 78 patients (median [interquartile range], 59 [51-66.3] years, 28.2% male) who underwent TV surgery for functional TR were comprehensively reviewed. Cox proportional hazards analyses were performed to assess the associations of clinical and imaging parameters with MACCEs and all-cause mortality. Results: For the median follow-up duration of 5.4 years (interquartile range, 1.2-6.6), MACCEs and all-cause mortality were 51.3% and 23.1%, respectively. The right ventricular (RV) end-systolic volume index (ESVI) and the systolic RV mass index (RVMI) were higher in patients with MACCEs than those without them (77 vs. 68 mL/m², p = 0.048; 23.5 vs. 18.0%, p = 0.011, respectively). A high RV ESVI was associated with all-cause mortality (hazard ratio [HR] per value of 10 higher ESVI = 1.10, p = 0.03). A high RVMI was also associated with all-cause mortality (HR per increase of 5 mL/m² RVMI = 1.75, p < 0.001). After adjusting for age and sex, only RVMI remained a significant predictor of MACCEs and all-cause mortality (p < 0.05 for both). After adjusting for multiple clinical variables, RVMI remained significantly associated with all-cause mortality (p = 0.005). Conclusion: RVMI measured on preoperative cardiac MRI was an independent predictor of long-term outcomes in patients who underwent TV surgery for functional TR.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.13 no.4
• /
• pp.320-324
• /
• 2008

In order to identify the change of tidal characteristics on average in the Asan Bay due to the construction of the Hwaong (Namyang Bay) tidal barrier (HTB), the tide data at Pyongtack (PT) and Anheung (AH) for the periods from 1993 to 2006 were analyzed using the harmonic analysis method, and major and shallow water tidal constituents were compared. The semidiurnal tidal amplitudes at PT increased while those at AH decreased after the tidal barrier construction. In particular, the amplitudes at PT increased abruptly during the period of $2002{\sim}2003$ when HTB was completed. On the other hand, the amplitudes of the diurnal tides at PT and AH showed minimal change. This suggests that the tidal characteristics change in the Asan Bay may be related to the construction of HTB. The cause of this change is different from either blocking the tidal wave propagation by the Keum River tidal barrier or removing 'choking effect' by the Yeongsan River tidal barrier. The $M_4/M_2$ ratio increased and their phase difference decreased after the completion of HTB. Accordingly, these changes may result in increase of tidal range, decrease of the flood duration and increase of the flood current velocity, inducing more sediments into the Asan Bay.

• Korean Circulation Journal
• /
• v.54 no.9
• /
• pp.534-544
• /
• 2024

Background and Objectives: Lipid lowering therapy is essential to reduce the risk of major cardiovascular events; however, limited evidence exists regarding the use of statin with ezetimibe as primary prevention strategy for middle-aged adults. We aimed to investigate the impact of single pill combination therapy on clinical outcomes in relatively healthy middle-aged patients when compared with statin monotherapy. Methods: Using the Korean National Health Insurance Service database, a propensity score match analysis was performed for baseline characteristics of 92,156 patients categorized into combination therapy (n=46,078) and statin monotherapy (n=46,078) groups. Primary outcome was composite outcomes, including death, coronary artery disease, and ischemic stroke. And secondary outcome was all-cause death. The mean follow-up duration was 2.9±0.3 years. Results: The 3-year composite outcomes of all-cause death, coronary artery disease, and ischemic stroke demonstrated no significant difference between the 2 groups (10.3% vs. 10.1%; hazard ratio [HR], 1.022; 95% confidence interval [CI], 0.980-1.064; p=0.309). Meanwhile, the 3-year all-cause death rate was lower in the combination therapy group than in the statin monotherapy group (0.2% vs. 0.4%; p<0.001), with a significant HR of 0.595 (95% CI, 0.460-0.769; p<0.001). Single pill combination therapy exhibited consistently lower mortality rates across various subgroups. Conclusions: Compared to the statin monotherapy, the combination therapy for primary prevention showed no difference in composite outcomes but may reduce mortality risk in relatively healthy middle-aged patients. However, since the study was observational, further randomized clinical trials are needed to confirm these findings.

• Pediatric Infection and Vaccine
• /
• v.14 no.1
• /
• pp.83-90
• /
• 2007

Purpose : Staphylococcal scalded skin syndrome (4S) is a well known disease defined by clinical, microbiological and histological criteria caused by Staphylococcus aureus. This disease is uncommon but has been increasingly recognized. We investigated the clinical features of staphylococcal scalded skin syndrome. Methods : We reviewed retrospectively medical records of 53 patients diagnosis of staphylococcal scalded skin syndrome who were admitted to Changwon Fatima hospital from February 2002 to December 2005. These patients were divided into 3 clinical types; generalized type, intermediate type, abortive type. Age, sex ratio, clinical manifestations, laboratory findings, response to therapy and prognosis were investigated. Result : 1)The mean age of patients was 2.8 years, ranging from 20 days to 7 years. Male-to-female ratio was 1.9:1. 2) By clinical types, 6 patients were in the generalized type (11%), 29 patients in the intermediate type (55%), 18 patients in the abortive type (34%). The coexisting diseases were variable, including conjunctivitis (25 cases), atopic dermatitis (11 cases), otitis media (1 case). On laboratory findings, most of patients didn't have leukocytosis or increased C-reactive protein. 4) A total of fifteen Methicillin Resistant Staphylococcal Aureus (MRSA) strains were isolated from September 2003 through December 2005. Fourteen strains were positive for exfoliative toxin B gene by PCR and negative for enterotoxin, toxic shock syndrome toxin and Panton-Valentine leukocidin genes. 5) The mean duration of admission was 7.3 days. Patients were treated with vancomycin or amoxacillin/clavulanate or ampicillin/sulbactam or cefuroxime without significant sequelaes. Conclusion : Recently, Staphylococcal scalded skin syndrome caused by exfoliative toxin B produced by MRSA in the Changwon area has been increasing.

• Journal of Sericultural and Entomological Science
• /
• v.26 no.2
• /
• pp.11-15
• /
• 1984

To save the labour reguired for separation of copulated moth during egg Production, some of the chemicals available at the market were on screen test for easy separation of copulated moth of silkworm. The obtained results are summarized as following. 1. In a separation ratio of copulated moth along with a treating time, TCTFE(Trichloro-trifluoroethane) completely separated the copulated moth in 10 minutes. The combinations of TCTFE plus Acetone (87.5 : 12.5 V/V) and TCTFE plus Acetic acid (50 : 50 V/V) take 25minutes for the complete separation of copulated moth. Use of Acetic acid solution only makes 100% separation of copulated moth in one hour and foully minutes and non$.$treatment shows only 47.5% of separation in three and half hours. On the other hand. There is no statistical significance between TCTFE Plus Acetone and control in the egg productivity. 2. The combination of TCTFE Plus Acetone (87.5 : 12.5 V/V) does not infuluence the egg productivity of the moth, showing 443 grains for an average number of egg per moth out of which 417 grains are for the number of fertilized eggs while control shows 452 grains for an avarage number of egg/moth and 428 grains for the number of fertilized eggs. However a sing1e use of TCTFE and Acetic acid shows less egg productivity and number of ferilized eggs per moth, respectively as compared to those of the control. In particular, a single use of acetic acid makes an increase of number of non-egg prodncible moth and it seems to be brought due to a chemical damage. 3. In a rearing test of the egg laid by the chemical treated moth, there are no differences among the treatments in all of the useful characters of the larvae; larval duration, survival rate, cocoon yield, single cocoon weight, single cocoon shell weight and cocoon shell ratio. In these regards, it is recognized that TCTFE can be practically used for the separation of copulated moth and the combination of TCTFE and Acetone promote its efiectiveness on the separation of copulated moth.

• Childhood Kidney Diseases
• /
• v.5 no.2
• /
• pp.125-135
• /
• 2001

Purpose : Efforts to predict long-term outcome of focal segmental glomerulosclerosis(FSCS) have been made but have yielded conflicting results. Reports are rare especially in Pediatric patients. In this study, we reviewed the predictable prognostic factors in patients of FSGS Method : Fifty children who diagnosed as biopsy-proven FSGS at department of pediatrics at Yonsei university were studied retrospectively. Based on medical records, response to treatment and pathologic slides, we compared normal renal function group and decreased renal function group, assessed the factors affecting renal survival and progression to renal failure. Results : The mean age at onset was 8 1/12 years, sex ratio was 2.3 : 1, and the mean duration of follow-up was 7 1/12 years. The overall renal survival rate was $34\%$ at 5 years, $8\%$ at 10 years Five-year survival rate was $74\%$ in normal renal function group and $27\%$ in decreased renal function group. Between the two groups, there were no significant differences in age at onset, sex ratio, amount of proteinuria, incidence of hematuria and hypertension, mesangial hypercellularity. Decreased renal function group showed higher serum creatinine level, poor response to treatment, higher percent of glomeruli with sclerosis, moderate to severe tubulointerstitial change and vascular change(P<0.05). The prognostic factors of renal survival rate were same as above and incidence of hypertension also affected renal survival( P<0.05). The progression rate to renal failure did not show statistically significant factor. Conclusion : We reviewed the factors affecting long-term outcome of FSGS. Serum creatinine level, steroid responsiveness, and the degree of glomerulosclerosis were significant prognostic factors. (J Korean Soc Pediatr Nephrol 2001 ;5 : 125-35)