• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1039-1042
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• 2008

In order to increase a functionality, OH value, for a recycled polyol prepared from the glycolysis reaction of a waste polyurethane rigid foam(PUR), the effect of an addition of pentaerythritol(PEN, functionality(f)=4) or sorbitol(SOR, f=6) to the its glycolysis reactor on the prepared polyol functionality and the mechanical properties of the polyurethane prepared using it was investigated. The OH values increased from 2.2 for a virgin to 2.8 for the recycled polyol. There was an increase in the mechanical properties including dimensional stability for PUR prepared using the recycled polyol, in which the increased OHs provided higher crosslinking density during PUR synthesis. In addition, the amount of the recycled polyol in the polyol system increased to from 8 to 20 wt% to give better mechanical properties to the PUR.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.87-95
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• 2020

Generally, occupational safety and particularly construction safety is an intricate phenomenon. Industry professionals have devoted vital attention to enforcing Occupational Safety and Health (OHS) from the last three decades to enhance safety management in construction. Despite the efforts of the safety professionals and government agencies, current safety management still relies on manual inspections which are infrequent, time-consuming and prone to error. Extensive research has been carried out to deal with high fatality rates confronting by the construction industry. Sensor systems, visualization-based technologies, and tracking techniques have been deployed by researchers in the last decade. Recently in the construction industry, computer vision has attracted significant attention worldwide. However, the literature revealed the narrow scope of the computer vision technology for safety management, hence, broad scope research for safety monitoring is desired to attain a complete automatic job site monitoring. With this regard, the development of a broader scope computer vision-based risk recognition system for correlation detection between the construction entities is inevitable. For this purpose, a detailed analysis has been conducted and related rules which depict the correlations (positive and negative) between the construction entities were extracted. Deep learning supported Mask R-CNN algorithm is applied to train the model. As proof of concept, a prototype is developed based on real scenarios. The proposed approach is expected to enhance the effectiveness of safety inspection and reduce the encountered burden on safety managers. It is anticipated that this approach may enable a reduction in injuries and fatalities by implementing the exact relevant safety rules and will contribute to enhance the overall safety management and monitoring performance.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1364-1369
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• 2009

Purpose : To analyze abnormal ventricular activation in childhood congenital heart disease induced by postoperative changes in ventricular volume and pressure and ventricular scar formation using signal-averaged electrocardiography (SAECG). Methods : Fifty-two patients who had undergone open heart surgery (OHS) were enrolled. Patients were divided into the following 3 groups: right ventricular volume overload (atrial septal defect, group1), left ventricular volume overload (ventricular septal defect, group2), and right ventricular pressure overload (tetralogy of Fallot, group 3). The patients were monitored by standard 12-lead ECG and SAECG before and 2 months after the operation. QRS duration, QT and QTc intervals, filtered QRS (f-QRS), high frequency low amplitude potential (HFLA), and root mean square (RMS) voltage in the terminal 40 ms of SAECG were determined. Results : In the preoperative period, group1 showed significant increase in QRS (P=0.011) compared to those of the other 2 groups. In the postoperative period, group3 showed significant increase in the QTc interval (P=0.004) compared to those in the other 2 groups. SAECG parameters showed no significant differences among the groups in the pre- or postoperative period. Of the 52 patients, 12 (23%) in the preoperative period and 21 (40%) in the postoperative period had at least 1 SAECG abnormality. The prevalence of SAECG abnormalities was significantly higher in the postoperative group 2 and group 3 (preoperative: 20% versus postoperative: 28%, P<0.001, preoperative: 14% versus postoperative: 64%, P<0.001, respectively). Conclusion : Abnormal SAECG patterns may be attributed to postoperative scars, OHS itself, and/or ventricular overload.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1183-1194
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• 1998

Background: From Sept. 1985 to Sept. 1997, 2,000 cases of open heart surgery(OHS) were performed in the Department of Thoracic & Cardiovascular Surgery, Pusan Paik Hospital, College of Medicine, Inje University. Material and Method: Among the total of 2,000 cases of OHS, 1532 cases were congenital heart disease(CHD) and 468 cases were acquired heart disease(AHD). The age distribution was 9 days(4.0kg) to 68 years in CHD and 11 to 66 years in AHD. In 1532 cases of CHD, there were 1403 acyanotic cases and 129 cyanotic cases. Result: The CHD cases consisted of 940 ventricular septal defects(61.4%), 324 atrial septal defects(21.1%), 112 tetralogy of Fallot(7.3%), 46 pulmonary stenosis(3%), 38 endocardial cushion defects(2.5%), 15 valsalva sinus ruptures(1%), 4 transposition of great arteries (0.3%), 4 double outlet right ventricles(0.3%), and etc. Corrective operations were applied for congenital heart disease with a result of 3.1% hospital mortality. Of 468 AHD, 381 cases were valvular heart diseases, 48 ischemic heart diseases, 12 cardiac tumors, 8 annuloaortic ectasias, 16 dissecting aortic aneurysms and etc. In the 381 valvular heart diseases, there were 226 single valve replacements(36 aortic valve replacements(AVR), 188 mitral valve replacements(MVR), and 2 tricuspid valve replacements(TVR), among these were 71 cases of double valve replacements(AVR & MVR), 54 cases of MVR with tricuspid valve annuloplasty(TVA), and 18 cases of AVR, MVR with TVA. The total implanted prosthetic valves were 466. In MVR, 123 St. Jude Medical valves, 90 Carpentier-Edwards valves, 65 CarboMedics valves, 42 Sorin valves and 16 other valves were used. In AVR, 68 St. Jude Medical valves, 36 CarboMedics valves, 14 Carpentier-Edwards valves and 9 other valves were used. Coronary Artery Bypass Surgery(CABG) were performed in 48 cases. The patterns of bypass graft were 14 patients of single vessel graft, 21 patients of two vessels graft, 10 patients of three vessels graft and 3 patients of four vessels graft. Conclusion: The hospital operation mortality rate of congenital acyanotic, cyanotic and acquired heart diseases were 2.0%, 15.5%, and 5.1% respectively. The overall mortality rate was 3.6%(72/2,000).

• Journal of Chest Surgery
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• v.31 no.9
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• pp.867-872
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• 1998

Background: The fixed dose regimen with activated coagulation time(ACT) is the most commonly employed method for determining the required dosage of heparin and protamine during cardiopulmonary bypass(CPB). Material and Method: We performed a prospective study on a fixed dose regimen for analyzing adequate dosages of heparin and protamine, the incidence of heparin resistance and heparin-induced thrombocyt openia, factors affecting ACT during CPB, and changes of ACT during aprotinin usage. 300 units/kg of heparin were administered to patients, and ACTs were measured after 5 mins. ACTs were checked at 10 mins and 30 mins after the onset of CPB, and then at 30 min intervals thereafter. If the measured ACT was under 400 secs, we added 100 units/kg of heparin. The heparin was reversed with 1 mg of protamine for each 100 units administered. If the measured ACT was longer than 130 secs 30 mins after protamine administration or if there was definitive evidence of a coagulation defect, we administered a further 0.5 mg/kg of protamine. Result: We studied 80 patients(50 adults and 30 children) who underwent open heart surgery(OHS) at Seoul National University Hospital. Preoperative ACT was 114.3${\pm}$19.3 secs in adults, and 119.5${\pm}$18.2 secs in children. There were no differences in preoperative ACT due to age, body weight, body surface area, or sex. The preoperative ACT was not influenced by a positive past history of OHS. Ten adults(20%) and 3 pediatric patients(10%) needed additional doses of heparin to maintain the ACT above 400 secs. Additional protamine administration was needed in 9 adults(18%) and 10 children(33%). Heparin resistance was found in only two adults. Heparin-induced thrombocytopenia was detected in 2 adults and 1 child. During CPB, ACT was prolonged. 12 adult patients received a low dose of aprotinin and showed longer celite activated ACT compared to the control group.The kaolin activated ACT showed a lower tendency than the celite activated ACT in aprotinin users. Conclusion: In conclusion, fixed dose regimen of heparin and protamine can be used without significant problems, but the incidence of need of additional dosage remains unsatisfactory.

• Journal of Chest Surgery
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• v.34 no.6
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• pp.454-464
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• 2001

Background: It has been recognized that systemic inflammatory reaction and oxygen free radical formed by activated leukocyte in the procedure of cardiopulmonary bypass(CPB) frequently produce postoperative cardiac and pulmonary dysfunction. The purpose of this study was to evaluate the efficacy of leukocyte-depleting filters in the cardiopulmonary bypass circuit for patients undergoing open heart surgery(OHS). Material and method: The study involved 15 patients who underwent OHS with a Leukoguard-6 leukocyte filter placed in the arterial limbs of the bypass circuit(filter group, n=15) and 15 patients who did not have the filter(control group, n=15). We analyzed the differences between the groups in intraoperative changes of peripheral blood leukocyte and platelet counts, pre- and postbypass changes of malondialdehyde(MDA), troponin-T(TnT), 5'-nucleotidase(5'-NT) in coronary sinus blood, spontaneous recovery rate of heart beat after CPB, pre-and postoperative cardiac index(Cl) and pulmonary vascular resistance(PVR), and the amounts of postoperative bleeding and sternal wound complication. Result: During CPB, total leukocyte count of the filter group(9,567$\pm$ 842/㎣) was significantly less than that of the control group(13,573+1,167/㎣) (p<0.01), but there was no significant difference in platelet count between the groups. Postoperative levels of MDA(3.78+0.32 $\mu$mol/L vs 5.86+0.65 $\mu$mo1/L, p<0.01), TnT(0.40$\pm$0.04 ng/mL vs 0.59$\pm$0.08 ng/mL, p<0.05) and 5'-NT(3.88$\pm$0.61 U/L vs 5.80$\pm$0.90 U/L, p<0.05) were all significantly lower in the filter group than the control group. Postoperative Cl was higher in the filter group than the control group(3.26$\pm$0.18 L/$m^2$min vs 2.75$\pm$0.17 L/$m^2$/min, p=0.05). PVR of the filter group was lower than that of the control group(65.87$\pm$7.59 dyne/sec/cm$^{5}$ vs 110.80+12.22 dyne/sec/cm$^{5}$ , p<0.01). Spontaneous recovery rate of heart beat in the filter group was higher than that in the control group(12 patients vs 8 patients, p<0.05). Postoperative wound infection occurred in one case in the filter group and 4 case in the control group(p<0.05). Postoperative 24 hour blood loss of the filter group was more than that of the control group (614$\pm$107 mL vs 380+71 mL, p=0.05).

• Clinical and Experimental Reproductive Medicine
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• v.34 no.1
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• pp.49-56
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• 2007

Objective: To evaluate the effect of short coasting, by withdrawing both gonadotropins and GnRH agonist (GnRHa), on the prevention in severe ovarian hyperstimulation syndrome(OHSS) without compromising pregnancy outcome. Method: Thirty-seven women who had been coasted during COH for IVF were coasted when $\geq$20 follicles > 15 mm with serum E$_2$ level of 4,000 pg/ml were detected. Coasting was initiated for one or two days depending on the status of follicle on ultrasound and serum E$_2$ level. Both gonadotropin and GnRHa were withheld for coasting. Retrospective study was carried and changes of serum E$_2$ levels, number of oocytes retrieved, fertilization rate, pregnancy rate were compared and analyzed. Results: The mean serum E$_2$ level fell from 6,993 pg/ml on the onset of coasting to 3,396 pg/ml on the day of hCG administration. The mean number of oocytes retrieved and fertilization rate were 15.7 and 70.0%, respectively. Fifteen patients were pregnant (40.6%) and implantation rate was 15.2%. Twenty-six (70.3%) patients were coasted for one day and 11 (29.7%) were coasted for two days. The mean decrease rate of serum E$_2$ level was 43% in one day coasting group and 15% (1$^{st}$ day) and 81% (2$^{nd}$ day) in two day coasting group. The pregnancy outcome was similar between the two groups. After coasting, no severe or moderate OHSS occurred in any patients and mild OHSS occurred in 3(8.1%) patients. Conclusions: Coasting for one or two days can be used successfully in the prevention of OHSS without compromising IVF cycle outcome.

• Journal of Agricultural Extension & Community Development
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• v.21 no.4
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• pp.1007-1028
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• 2014

This study aimed to explore the direction of development of agricultural safety and health system in Korea based on experience on Farmers' Occupational Health Services (FOHS) of Finland. In Finland additional and specialized Occupational Health Services (OHS) for self-employed farmers were developed and have been conducted by municipal primary health care centers with cooperation of National Centre for Agricultural Health (NCAH) of Finnish Institute of Occupational Health, Social Insurance Institute (SII) and Farmers' Social Insurance Institution (FSII). Based on the study, in order to activate the FOHS in Korea, the analysis results could suggest the development of four prerequisites. Firstly, center for farmers' safety and health like NCAH, which conducts surveillance on health and safety status, standardization of intervention contents and epidemiological research is needed in national institution. Secondly, development of evaluation tools with lower cost and difficulty like walk-through survey for checking status of systems of safety in the farms is needed. Thirdly, farmers' occupational health insurance which will be initiated on near future should be connected to preventive intervention programs like FOHS. Lastly, training and qualification of more local occupational health experts and units is needed.

• Natural Product Sciences
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• v.13 no.1
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• pp.33-39
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• 2007

Eleven polyhydroxyursane triterpenoids (PHUTs) were tested to determine their cytoprotective, immunosuppressive and anti-inflammatory effects. To compare the bioactivities of $19{\alpha}$-hydroxyursane-type triterpenoids {23-hydroxytormentic acid (6), its methyl ester (7), tormentic acid (8), niga-ichigoside $F_1$ (9),euscaphic acid (10) and kaji-ichigoside $F_1$ (11)} of the Rosaceae crude drugs (Rubi Fructus and Rosa rugosae Radix) with PHUTs possessing no $19{\alpha}-hydroxyl$ of Centella asiatica (Umbelliferae), the four PHUTs, asiaticoside (1), madecassoside (2), asiatic acid (3), and madecassic acid (4) were isolated from C. asiatica and 23-hydroxyursolic acid (5) from Cussonia bancoensis. Cytoprotective effects were assessed by measuring cell viabilities against cisplatin-induced cytotoxocity in $LLC-PK_1$, cells (proximal tubule, pig kidney) to determine whether these agents have protective effects against nephrotoxicity caused by cisplatin. The inhibitory effect of 11 PHUTS on nitric oxide (NO) and prostaglandin $E_2\;(PGE_2)$ were evaluated by measuring nitrite accumulation in lipopolysaccharide (LPS)-induced macrophage RAW 264.7 cells, and their anti-inflammatory effects were tested in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema model. Six MHUTs (compounds 1, 2, 4, 6, 10, and 11) exhibited higher cell viabilities during cisplatin-induced cytotoxicity testing even at a concentration of $200\;{\mu}g/ml$ than cisplatin only-treated group, suggesting that ese compounds have the potentcytoprotective efffcts. Compounds 1 and 3 of the C. asiatica and niga-ichigoside $F_1$ exhibited no inhibitory effect on NO and/or $PGE_2$ production whereas other PHUTs produced mild to significant NO and/or $PGE_2$ production.The four compounds (2, 5, 9, and 10) potently inhibited mouse ear edema induced by TPA whereas two compounds (1 and 3) had no activity in this test. These results suggest that many PHUTs are potentchemopreventives. Structure-activity relationship (SAR) was also discussed in each assay with regard to the significant role of OHs at the position of 2, 3, 6, 19, and 23 and to the glycoside linkage at the 28-carboxyl.

• Clinical and Experimental Reproductive Medicine
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• v.22 no.2
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• pp.171-181
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• 1995

Ovarian hyperstimulation syndrome(OHSS) is one of the well-known complication of controlled ovarian hyperstimulation(COH). Though there have been numerous measures to prevent the occurrence of OHS, it has not been completely preventable until now. The fluid shift from the intravascular space to the third space is due to decreased oncotic pressure of the serum. The objective of this study was to evaluate if IV administration of 20% albumin in those patients with OHSS risk can make prevention of severe OHSS. We retrospectively analysed 70 patients undergoing IVF-ET who had serum peak estradiol($E_2$) level of >2,500 pg/ml and/or the number of oocytes retrieved over 20. The treatment group(n=39) received albumin while the control group(n=31) did not. After 40 grams of human albumin diluted in 1,000 ml of 0.9% sodium chloride solution, the treatment group received half of the fluid during oocyte retrieval, the remainder in the recovery suite. The results were as follows; There were significant differences in the levels of serum peak $E_2$ and number of oocytes retrieved between the two groups(p<0.05). However, there were no significant differences in the incidence of OHSS and pregnancy rate or multifetal pregnancy rate. In conclusion, administration of albumin to OHSS risk patients did not reduce the rate of OHSS in IVF-ET. However, if we consider the fact that there were differences in the level of peak serum $E_2$ and oocyte numbers, further prospective study may be needed.