• Title/Summary/Keyword: reflux ratio

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Effects of Extraction Condition on Extraction Efficiency of Rubiadin in Adventitious Roots of Noni (Morinda citrifolia) (추출조건이 노니 부정근에 함유된 rubiadin의 추출 효율에 미치는 영향)

  • Kim, Myong-Ki;Jeong, Cheol-Seung;Shin, Yong-Kook;Park, Kyong-Hee;Lee, Woon-Jang;Lee, Eun-Jung;Paek, Kee-Yoeup
    • Horticultural Science & Technology
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    • v.28 no.4
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    • pp.685-690
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    • 2010
  • Rubiadin, a major compound of noni ($Morinda$ $citrifolia$) adventitious root, is highly valued in pharmaceutical industry due to hepatoprotective activity. To dissect rubiadin's effective extraction condition, extraction process of noni adventitious roots was performed with different solvent types, ratio of water to methanol (water, 20, 40, 60, 80, and 100% of methanol), extraction time, and extraction method. In contrast, we also developed a reverse- phase HPLC assay method to determine rubiadin from noni adventitious roots. The HPLC assay of rubiadin was performed by C-18 column using a gradient solvent system of methanol and water with UV detector at 280 nm. The extraction efficiency of different types of solvents were increased in order of methanol (0.08%) > ethanol (0.05%) > acetonitrile (0.03%) > acetone (0.02%) and methylene chloride (0.02%). The results of rubiadin extraction using different solvents showed that 1 hour of ultrasonic extraction was effective in order of 60% methanol (0.21%) > 80% methanol (0.13%) > 100% methanol (0.07%), 40% methanol (0.07%) and 2 hours of reflux extraction was effective in order of 60% methanol (0.21%) > 40% methanol (0.17%) > 80% methanol (0.14%). To compare the extraction efficiency of rubiadin according to the extraction methods and time for high rubiadin content, the extracts of rubiadin in noni adventitious roots were isolated with the methods of ultrasonic extraction, shaking extraction and reflux extraction. Rubiadin extracted from the methods of ultrasonic waves and shaking displayed the highest contents at 8 and 24 hours, respectively.

Fabrication of Mono-Dispersed Ultrafine BaTiO$_3$ Powder Using Microwave (마이크로파를 이용한 초미세 균일 분산 BaTiO$_3$ 분말 제조)

  • 김현상;최광진;이상균;김영대;심상준;우경자;김경림;조영상
    • Journal of the Korean Ceramic Society
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    • v.36 no.4
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    • pp.343-353
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    • 1999
  • Microwave(2.45 GHz) was used as energy source in hydrothermal reaction to fabricate ultrafine BaTiO3 powder. Using microwave of 700 W, crytal BaTiO3 began to fom after 5 min in microwave-autoclave sys-tem. The crystallinity was not noticeably increased with increasing longer reaction time than 10 min. On the other hand in microwave-reflux system crytal BaTiO3 began to form after 15min and the crystallinity was not noticeably increased with increasing longer reaction time than 1hr,. In either case particle size dis-tribution was considerably uniform due to the effect of homogeneous heating by microwave. In addition mi-crowave heating gave an extremely small degree of particle agglomeration compared to electric heating. Av-erage sizes of as-synthesized powders were 30-60nm. Ba/Ti ratio in sol played an important role in det-ermining the particle size. It seems that excess barium forms different phases such as Ba(OH)2 which makes thin layer on the surface of BaTiO3 powder. This thin layer would inhibit the agglomeration of Ba-TiO3 powders and keep the small grain size. In microwave-autoclave system tetragonal-BaTiO3 was formed directly by the reaction of only 15 min. In the case of microwave-reflux system tetragonal-BaTiO3 was formed by driyng over 25$0^{\circ}C$.

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Vertebral Venous Congestion That May Mimic Vertebral Metastasis on Contrast-Enhanced Chest Computed Tomography in Chemoport Inserted Patients

  • Jeong In Shin;Choong Guen Chee;Min A Yoon;Hye Won Chung;Min Hee Lee;Sang Hoon Lee
    • Korean Journal of Radiology
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    • v.25 no.1
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    • pp.62-73
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    • 2024
  • Objective: This study aimed to determine the prevalence of vertebral venous congestion (VVC) in patients with chemoport insertion, evaluate the imaging characteristics of nodular VVC, and identify the factors associated with VVC. Materials and Methods: This retrospective single-center study was based on follow-up contrast-enhanced chest computed tomography (CT) of 1412 adult patients who underwent chemoport insertion between January 2016 and December 2016. The prevalence of venous stenosis, reflux, and VVC were evaluated. The imaging features of nodular VVC, including specific locations within the vertebral body, were analyzed. To identify the factors associated with VVC, patients with VVC were compared with a subset of patients without VVC who had been followed up for > 3 years without developing VVC after chemoport insertion. Toward this, a multivariable logistic regression analysis was performed. Results: After excluding 333 patients, 1079 were analyzed (mean age ± standard deviation, 62.3 ± 11.6 years; 540 females). The prevalence of VVC was 5.8% (63/1079), with all patients (63/63) demonstrating vertebral venous reflux and 67% (42/63) with innominate vein stenosis. The median interval between chemoport insertion and VVC was 515 days (interquartile range, 204-881 days). The prevalence of nodular VVC was 1.5% (16/1079), with a mean size of 5.9 ± 3.1 mm and attenuation of 784 ± 162 HU. Nodular VVC tended to be located subcortically. Forty-four patients with VVC underwent CT examinations with contrast injections in both arms; the VVC disappeared in 70% (31/44) when the contrast was injected in the arm contralateral to the chemoport site. Bevacizumab use was independently associated with VVC (odds ratio, 3.45; P < 0.001). Conclusion: The prevalence of VVC and nodular VVC was low in patients who underwent chemoport insertion. Nodular VVC was always accompanied by vertebral venous reflux and tended to be located subcortically. To avoid VVC, contrast injection in the arm contralateral to the chemoport site is preferred.

Optimization of biodiesel production via methyl acetate reaction from cerbera odollam

  • Dhillon, Sandip Singh;Tan, Kok Tat
    • Advances in Energy Research
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    • v.4 no.4
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    • pp.325-337
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    • 2016
  • Cerbera Odollam (sea mango) is a proven promising feedstock for the production of biodiesel due to its high oil content. Fatty acid methyl esters (FAME) were produced as the final reaction product in the transesterification reflux condensation reaction of sea mango oil and methyl acetate (MA). Potassium methoxide was used as catalyst to study its reacting potential as a homogeneous base catalyst. The initial part of this project studied the optimum conditions to extract crude sea mango oil. It was found that the content of sea mango sea mango oil was 55%. This optimum amount was obtained by using 18 g of grinded sea mango seeds in 250 ml hexane. The extraction was carried out for 24 hours using solvent extraction method. Response surface methodology (RSM) was employed to determine the optimum conditions of the reaction. The three manipulated variables in this reaction were the reaction time, oil to solvent molar ratio, and catalyst wt%. The optimum condition for this reaction determined was 5 hours reaction time, 0.28 wt% of catalyst and 1:35 mol/mol of oil: solvent molar ratio. A series of test were conducted on the final FAME product of this study, namely the FTIR test, GC-FID, calorimeter bomb and viscometer test.

Isolation and Characterization of Acidic Polysaccharides Activating Complement System from the Hot Water Extracts of Pteridium aquilinum var. latiusculum (고사리 열수 추출물로부터 보체계 활성화 산성 다당의 분리 및 특성)

  • O, Byeong-Mi;Gwon, Mi-Hyang;Na, Gyeong-Su
    • The Korean Journal of Food And Nutrition
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    • v.7 no.3
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    • pp.159-168
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    • 1994
  • From the hot water extract of bracken(Pteridium aquilinum var. latiusculum), a Korean win edible plant, anti-complementary acidic polysaccharides were Isolated. Crude polysaccharide fraction(HPA-1) was obtain ed by methanol reflux, ethanol precipitation, dialysis, and lyophilization. HPA-1 contained 81.80% of total sugar, 30.40% of uronic acid, and 15.60cA of protein. HPA 1 was purified consecutively by cetavlon fractionation and chromatography including ion exchange nth DEAE-Sepharose CL 6B and gel permeation with Sephadex G-100 and Sepharose CL-6B. HPA-2- IVa and HPA-Va-2 were nearly homogeneous on HPLC and had 500,000 and 560,000 daltons of molecular weights, respectively. HPA-2-Wa consisted of fucose, galacturonic acid, and glucuronic acid at the molar ratio of 1.40 : 0.97 : 1.88. HPA-2-Va 2 was composed of rhamnose, galactose, and galacturonic acid at the molar ratio of 1.00 : 1.38 : 1.39. The polysaccharides were found to activate the C3 component both In the presence and In the absence of Ca2+ through the crossed-immunoelectrophoresis suggesting that those Involved in both classical and alternative complement pathway.

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The Effect of Nasal Steroid Spray on Contact Granuloma of Larynx (접촉성 육아종 치료에 비강 스테로이드 분무가 미치는 영향)

  • Lee, GilJoon;Ahn, Dongbin;Sohn, Jin Ho
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.29 no.2
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    • pp.79-82
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    • 2018
  • Background and Objectives : Laryngeal contact granuloma is benign inflammatory disease induced by excessive mechanical contact of larynx such as endotracheal intubation, voice abuse, laryngeal microsurgery as well as laryngopharygeal reflux. Because it is caused by various risk factors, multiple treatment modalities are required. The purpose of study is to evaluate treatment effect of topical steroid through nasal cavity in contact granuloma. Materials and Method : Fifty-two patients were enrolled in this study with exception of intubation granuloma. Patients were classified with four groups (Proton pump inhibitor (PPI), Nasal steroid spray (SPR), PPI+SPR, Observation) according to treatment modality. Results : Patients who treated with PPI (Odds ratio 2.45, p=0.03) and combination of PPI and SPR (Odds ratio 2.88, p<0.01) had significantly better response than patients who not treated with medical therapy. Conclusion : Combination therapy of nasal steroid spray and PPI is effective for contact granuloma of larynx and considered as a treatment of choice rather than PPI only treatment.

Esophageal Cancer and Sex Hormones (식도암과 성호르몬)

  • Yu Jin Kim
    • Journal of Digestive Cancer Research
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    • v.11 no.2
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    • pp.61-65
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    • 2023
  • Globally, esophageal cancer is the seventh most common cancer, and the male-to-female ratio in esophageal adenocarcinoma (EAC) is significantly imbalanced at 4:1 to 8:1. Obesity, reflux, and smoking are known risk factors for this sex difference; however, fully explaining this remains challenging. Studies have investigated the link between exogenous sex hormones and esophageal cancer occurrence. A meta-analysis revealed a lower risk of EAC in female who had undergone hormone replacement therapy. Androgen-deprivation therapy in patients with prostate cancer was associated with a decreased risk of EAC. Tissue-based studies have reported varied results regarding the relationship between estrogen receptor expression and survival in female patients with esophageal squamous cell carcinoma (ESCC). Circulating hormone studies have suggested that higher testosterone and luteinizing hormone levels decreased EAC risk in men, and free testosterone was inversely correlated in female with ESCC. However, a high androgen-estrogen ratio in male patients with EAC was linked to increased odds of EAC. Sex hormones influence carcinogenesis, affecting cell proliferation, differentiation, metabolism, inflammation, and cell death. The studies were limited by the small sample size and varying hormone measurement methods; thus, future studies with definitive conclusions on the association between esophageal cancer and sex hormones are warranted.

Dialysis in double-pass cross-flow rectangular membrane modules with external recycle for improved performance

  • Yeh, Ho-Ming
    • Membrane and Water Treatment
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    • v.2 no.2
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    • pp.75-89
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    • 2011
  • The predicting equations for mass transfer rate in cross-flow rectangular dialyzers with double flow and recycle, have been derived by mass balances. The recycling operation has two conflicting effects. One is the desirable effect of the increase in fluid velocity, resulting in an increased mass transfer coefficient. The other is the undesirable effect of the reduction in concentration difference due to remixing, resulting in decreased mass-transfer driving force. In contrast a single-pass device without recycling, considerable improvement in mass transfer is achieved if the cross-flow rectangular dialyzer of same size is operated with double pass and external recycling. It is concluded that recycle can enhance mass transfer, especially for larger reflux ratio.

Urinary Protein and Enzyme Excretion of Spot Urine in Children with Vesicoureteral Reflux (방광요관 역류증 환아의 단회뇨에서 요단백 및 효소 배설 측정)

  • Yoon, Jung-Rim;Koo, Ja-Wook
    • Childhood Kidney Diseases
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    • v.13 no.1
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    • pp.56-62
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    • 2009
  • Purpose : The aim of this study was to evaluate the clinical usefulness of measurement of ${\beta}_2$ microglobulin (${\beta}_2$ MG), N-acetyl-$\beta$-D-glucosaminidase (NAG) of spot urine samples as indices of renal tubular damage and microalbumin of spot urine samples as a parameter of glomerular damage in children with vesicoureteral reflux (VUR) or renal defects. Methods : We studied 91 children with previous UTI. The children were classified as 62 children without VUR and renal defects (group I), 10 children with VUR, without renal defects (group II), and 19 children with VUR and renal defects (group III). Patients having VUR were separated according to the degree of VUR (mild VUR: VUR grade I-III, severe VUR: VUR grade IV-V). Urinary excretion of ${\beta}_$ microglobulin (${\beta}_2$ MG), microalbumin, N-acetyl-$\beta$-D-glucosaminidase (NAG), creatinine were measured in samples of morning urine specimens. Children with VUR or renal defects detected by voiding cystourethrography (VCUG) and DMSA renal scan were investigated. Results : Microalbumin/Cr ratio of spot urine was significantly increased in group III compared group I ($42.3{\pm}27.2\;mg/gCr$ vs $25.2{\pm}10.9\;mg/gCr$, P<0.05). NAG/Cr ratio of spot urine was significantly increased in group II compared group I ($3.70{\pm}23.4\;mg/gCr$ vs $18.7{\pm}12.7\;mg/gCr$, P<0.05). There was no statistically significant difference of ${\beta}_2$ MG/Cr ratio among three groups. Conclusion : Urinary microalbumin excretion of morning urine sample may be a simple and reliable clinical indicators for early identification of renal damage in children with VUR and renal defects. Urinary microalbumin excretion may be useful marker to predict the the severity of VUR.

Preparation of Ferroelectric (YbxY1-x)MnO3 Thin Film by Sol-Gel Method (졸-겔법에 의한 (YbxY1-x)MnO3강유전체 박막제조)

  • 강승구;이기호
    • Journal of the Korean Ceramic Society
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    • v.41 no.2
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    • pp.170-175
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    • 2004
  • The ferroelectric (Y $b_{x}$ $Y_{1-x}$)Mn $O_3$ thin films were fabricated by sol-gel method using Y-acetate, Yb-acetate, and Mn-acetate as raw materials. The stable (Y $b_{x}$ $Y_{1-x}$)Mn $O_3$ precursor solution (sol) was prepared through the reflux process with acetylaceton as a catalyst and coated on Si(100) substrate by spin coating. The heat treatment temperature and, Rw ($H_2O$/alkoxide moi ratio) dependence on crystallinity of thin films were studied. The lowest temperature for obtaining YbMn $O_3$phase and the optimum heat-treatment conditions were proved as at 7$50^{\circ}C$ and 80$0^{\circ}C$, respectively. The hexagonal YbMn $O_3$with c-axis preferred orientation could be obtained at Rw=1 condition. The remanent polarization for the thin films of x=0 or 1 was about 200 nC/㎤ while, for the specimens ot 0< x< 1, were 50∼100 nC/$\textrm{cm}^2$.