• Clean Technology
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• v.14 no.3
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• pp.176-183
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• 2008

The purpose of this study is to upgrade the catalysts for synthesizing mixed octenes using normal butene and the catalysts for synthesizing $C_9$-aldehyde through hydroformylation of mixed octenes with syngas. The in-line activation method with circulating activating solution was effective for activation of the $NiO/A1_{2}O_3$ catalyst. The reason for catalyst deactivation may be ascribed to physi-sorbed materials or oligomers which block pore entrance and then prevent active sites from participating a reaction. Continuous distillation apparatus was used for separating mixed octenes from dimerization products. When reflux ratio was above 3 : 1, mixed octene fraction of which purity was above 99.57% was obtained. In $C_9$-aldehyde synthesis through hydroformylation of mixed octenes, we investigated a performance of ligand which increased catalyst stability as well as activity of Co catalyst. The results indicated that TPPO, NMP, NDMA, and succinonitrile were suitable ligand for increasing initial activity and reducing loss of Co during catalyst recovery.

• Korean Journal of Plant Resources
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• v.23 no.1
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• pp.47-53
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• 2010

Flowers and shoots of three species of Dendranthema boreale, Dendranthema indicum, Dendranthema zawdskii var. lucidum, were extracted with 80% ethanol by reflux, and polyphenol content, scavenging activity on DPPH and ABTS radicals, ferrous ion chelating effects and inhibition effects on lipid peroxidation were analyzed. Total polyphenol and flavonoid contents were highest in D. zawdskii var. lucidum, especially in the flower part. Scavenging activity on DPPH and ABTS was also highest in D. zawdskii var. lucidum flower with less activity in shoot. Ferrous ion chelating effects was highest with D. boreale flower and lowest in D. zawdskii var. lucidum flower. Inhibition activity on lipid peroxidation was highest in D. zawdskii var. lucidum shoot with 41.01% inhibition activity showing 32 days after reaction, which is higher than synthetic antioxidant BHT. Due to higher antioxidant level and activity of shoot and flower of D. zawdskii var. lucidum is promising material for natural plant antioxidant. It was also shown that antioxidant activity is different according to plant part ever in same plant, and proper plant species should be used for antioxidant after careful studies.

• Resources Recycling
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• v.7 no.3
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• pp.17-26
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• 1998

A study on the recovery of silver and nitric acid in the liquid waste resulted from the mediated electrochemical oxidation(MEO) process was conducted. The removal of silver in the concentrated nitric acid solutions was carried out by the electrodeposition. The removal efficiency more than 98% could be obtained in nitric acid concentrations less than 3 M with the current efficiency of nearly 100%. The experimonts on the evaporation for the recovery of nitric acid were performed as well. At the evaporation factor of 25., the degree of nitric acid recovery in 3.5 M nitric acid solution containing 0.5 to 1.0 mol% NaNO, was 80~90% resulting in 2.8~3.1 M nitric acid. The design factors and operating conditions of the distillation tower were analyzed by using MEH model derived by Maphtali-Sandholm with the throughput of 4 kg/hr for the enrichment of dilute nitric acid solution recovered by evaporation to reuse in the MEO process. The distillation column composed of eleven theoretical stages having the overall tray efficiency of 70% are needed to obtain 1.03 kg/h of 12M nitric acid and 2.97 kg/h of water with feed being introduced to the column at tray 6 from the bottom at the reflux ratio of 0.25, the reboiler with the heat load of 2.7 kW, and the condenser with the cooling load of 0.5 kW.

• Journal of Chest Surgery
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• v.34 no.10
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• pp.763-768
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• 2001

Background: The high pressure zone(HPZ) at the gastroesophageal junction is an important barrier for prevention of gastroesophageal reflux. Smooth muscle layers in the lower esophageal sphincter mainly contributes to HPZ at the throacoabdominal junction. The purpose of this study was to investigate the manometric characteristics of the thora-coabdominal junction in patients after surgical removal of the lower esophageal sphincter. Material and Method: Twenty two patients with prior esophagogastrectomy(10 Ivor-Lewis method and 12 left thoracotomy) and 30 normal adults(control group) were studied manometrically. Result: Esophageal manometry showed a HPZ and pressure inversion points distal to the anastomosis in 12 of 22 patients(2 of 10 patients with Ivor-Lewis method and 10 of 12 patients with left thoracotomy) and a HPZ in 30 of 30 normal adults. The location of HPZ front nostril was not significant different between the two groups(42.5$\pm$0.9cm in patients and 43.9$\pm$2.1cm in the control), while the length of HPZ was shorter in patients than in the control(2.13$\pm$0.6cm vs 2.83$\pm$0.59cm). By SPT and RPT, pressures of HPZ at rest were lower in patients(13.78$\pm$1.63mmHg, 28.58$\pm$6.06mmHg) than in control(20.3$\pm$4.95mmHg, 42.80$\pm$15.91mmHg). The HPZ relaxed partially in response to deglutition(84.4% in patient, 90.5% in control group) and contracted in response to increased intra- abdominal pressure induced by leg lifts(HPZ/ Intra-abdominal pressure= 1.81$\pm$0.23 in patient, 2.13$\pm$ 0.58 in control group).

• Pediatric Infection and Vaccine
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• v.22 no.3
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• pp.194-200
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• 2015

Purpose: Urinary tract infection (UTI) is a common bacterial infection in children and Escherichia coli is a predominant pathogen. The purpose of this study is to evaluate phylogenetic groups and virulence factors of E. coli causing UTI in children in Korea. Methods: From October 2010 to April 2013, urinary E. coli strains were isolated from the 33 pediatric patients of UTI. Multiplex polymerase chain reactions were performed to evaluate the phylogenetic groups and 5 virulence factor genes (fimH, sfa, papA, hylA, and cnf1) of E. coli. Distribution of molecular characteristics of E. coli was analyzed by clinical diagnosis and accompanying vesicoureteral reflux (VUR). Results: Most (84.8%) uropathogenic E. coli were belonged to phylogenetics group B2 and the others (15.2%) were belonged to group D. The virulence factors were distributed as: fimH (100%), sfa (100%), hylA (63.6%), cnfI (63.6%), and papA (36.4%). According to clinical diagnosis, phylogenetic distribution of E. coli strain was 92.3% of B2 and 7.7% of D in acute pyelonephritis and 57.1% of B2 and 42.9% of D in cystitis. Distribution of virulence factors was similar in both groups. In patients with acute pyelonephritis, phylogenetic distribution was similar in VUR and non-VUR group, but proportion of papA genes were lower in VUR group than that of non-VUR group (43.8% vs. 20.0%, P=0.399). Conclusions: This study provides current epidemiologic molecular data of E. coli causing pediatric UTI in Korea and will be a fundamental for understanding the pathogenesis of pediatric UTI.

• Childhood Kidney Diseases
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• v.9 no.1
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• pp.69-75
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• 2005

Purpose : The most important management of congenital hydronephrosis consists of the early diagnosis and evaluation of the pathologic abnormalities of congenital hydronephrosis. This study was conducted to investigate the different causes of hydronephrosis and its clinical outcome. Methods : 54 live neonates who were hospitalized and diagnosed with congenital hydronephrosis at Chungnam National University Hospital from Aug. 1998 to Aug. 2003 were retrospectively analyzed. Results : Hydronephrosis(renal pelvic AP diameter $gt;5 mm) was postnatally detected in 54 cases(2.1%) among 2,539 neonates who were hospitalized from Aug. 1998 to Aug. 2003. There were three times more males than females. Additional imaging studies revealed that ureteropelvic junction obstruction was the most common postnatal diagnosis(48.7%), followed by multicystic dysplastic kidney, vesicoureteral reflux and duplication kidney with ureterocele. Spontaneous regression of hydronephrosis was revealed in 25 renal units(75.8% ) of mild hydronephrosis, 14 renal units of moderate hydronephrosis and 1 renal unit of severe hydronephrosis. Operative correction were carried out in 14 renal units(70%) of severe hydronephrosls. Conclusion : The most common established cause of congenital hydronephrosis in this study was ureteropelvic junction obstruction. There are many cases of spontaneous regression in mild to moderate congenital hydronephrosis. Urinary tract infections occur in many neonates with hydronephrosis. Therefore, early detection and evaluation of congenital hydronephrosis and continuous follow-up at regular intervals are necessary for conservation of renal function. (J Korean Soc Pediatr Nephrol 2005;9:69-75)

• Childhood Kidney Diseases
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• v.17 no.2
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• pp.127-131
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• 2013

Urinomas can occur after renal trauma or perforation of the collecting system during an endosurgical procedure. However, spontaneous urinomas are very rare. Here we report a case of a spontaneous perinephric urinoma following the removal of a Foley catheter in an 18-year-old girl with acute kidney injury caused by septic shock. The patient had been treated for septic shock, acute kidney injury, and acute respiratory distress syndrome, and had a Foley catheter in place for seven days. After Foley catheter removal, the patient complained of consistent voiding difficulty. An abdominal computed tomography scan showed a large amount of left perinephric fluid, and the aspirated fluid included urothelial cells, confirming the diagnosis of a urinoma. The urinoma was successfully treated by insertion of a double-J stent into the left ureter. This report discusses the available literature on urinomas, and their clinical features, diagnosis, and treatment.

• Journal of Life Science
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• v.12 no.1
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• pp.87-95
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• 2002

It was observed that the hot water extract of the leaves of Capsicum annuum L., a Korean edible plant, had a potent anti-complementary activity. Crude polysaccharide fraction(CAL-0) was obtained by methanol reflux, ethanol precipitation, dialysis and lyophilization. CAL-0 contained 51.8% of total sugar, 8.2% of uronic acid and 16.8% of protein, and consisted of mainly arabinose, galactose and glucose as neutral sugars and galacturonic acid as uronic acid. The anti-complementary activity of CAL-0 decreased greatly by periodate oxidation, but was not changed by pronase treatment. Also, the anti-complementary activity of CAL-0 was reduced partially in the absence of the $Ca^{2+}$ ion. The crude polysaccharide CAL-0 was found to activate the C3 component both in the presence and in the absence of $Ca^{2+}$ through the crossed-immunoelectrophoresis suggesting that those involved in both classical and alternative complement pathway CAL-0 was further separated to an unabsorbed fraction(CAL-1) and six absorbed fractions(CAL-2longrightarrowCAL-7) on DEAE Sepharose CL-6B ion exchange column. Among them four major fractions in activity and yield were obtained, and consisted mainly of arabinose, galactose and glucose with various molar ratios. The major fraction, CAL-2, was purified to give a high molecular fraction(CAL-2-I) and a low molecular fraction(CAL-2-II) on Sepharose CL-6B column. The anti-complementary activity of CAL-2-I, a molecular weight of about 61,000, was higher than it of CAL-2-II.-II.

• Allergy, Asthma & Immunology Research
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• v.10 no.6
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• pp.591-613
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• 2018

Chronic cough is common in the community and causes significant morbidity. Several factors may underlie this problem, but comorbid conditions located at sensory nerve endings that regulate the cough reflex, including rhinitis, rhinosinusitis, asthma, eosinophilic bronchitis, and gastroesophageal reflux disease, are considered important. However, chronic cough is frequently non-specific and accompanied by not easily identifiable causes during the initial evaluation. Therefore, there are unmet needs for developing empirical treatment and practical diagnostic approaches that can be applied in primary clinics. Meanwhile, in referral clinics, a considerable proportion of adult patients with chronic cough are unexplained or refractory to conventional treatment. The present clinical practice guidelines aim to address major clinical questions regarding empirical treatment, practical diagnostic tools for non-specific chronic cough, and available therapeutic options for chronic wet cough in children and unexplained chronic cough in adults in Korea.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.486-491
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• 2019

Phenolic compounds and antioxidant activities of ethanol extracts from barley sprouts were evaluated in this study. Barley sprouts were extracted using water and ethanol in various concentration (25, 50, and 75%) using reflux extraction methods. Ultra performance liquid chromatography (UPLC) analysis showed that barley sprouts are mainly composed of rutin, gallic acid, ferulic acid, and ${\rho}$-coumaric acid. The 75% ethanol extracts had higher total polyphenol contents ($44.01{\pm}1.32mg/g$) and total flavonoid contents ($102.96{\pm}2.49mg/g$). 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity ($EC_{50}$ value: $1.65{\pm}0.02mg/mL$) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical scavenging activity ($EC_{50}$ value: $1.67{\pm}0.02mg/mL$) of the 75% ethanol extracts of barley sprouts were found to be the most effective. The 75% ethanol extracts of barley sprouts exhibited a strong reducing activity and ferric reducing antioxidant activity. As a result, the 75% ethanol extracts of barley sprouts showed stronger antioxidant activity than other extracts.