A New Flow Equation for Thixotropic Systems

Sohn, Dae-Won,Kim, Eung-Ryul,Hahn, Sang-Joon,Ree, Tai-Kyue Korean Chemical Society 1986 Bulletin of the Korean Chemical Society Vol.7 No.4

Thixotropy is a time-dependent shear-thinning phenomenon. We derived a new thixotropic formula which is based on the generalized viscosity formula of Ree and Eyring, $f={\Sigma}\frac{X_i}{{\alpha}_i}sinh^{-1}$ ($\beta_i{\cdot}{\dot{s}}$) (Refer to the text concerning the notation.) The following is postulated: (1) thixotropy occurs when small flow units attached to a large flow unit separate from the latter under stress (2) elastic energy(${\omega}$) is stored on the large flow unit during the flow process, and (3) the stored energy contributes to decrease the activation energy for flow. A new thixotropic formula was derived by using these postulations, $f={\frac}{X_0{\beta}_0}{\alpha_0}{\dot{s}}+{\frac}{X_1{\beta}_1}{{\alpha}_1}{\dot{s}}+{\frac}{X_2}{{\alpha_x}}sinh^{-1}$[$({\beta}_0)_2$ exp $(-C_2{\dot{s}}^2/RT){\cdot}{\dot{s}}$] f is the shear stress, and s is the rate of shear. In case of concentrated solutions where the Newtonian flow units have little contribution to the viscosity of the system, the above equation becomes, $f=\frac{X_2}{\alpha_2}sinh^{-1}$[$({\beta}_0)_2$ exp $(-C_2{\dot{s}}^2/RT){\cdot}{\dot{s}}$]. In order to confirm these formulas, we applied to TiO2(anatase and rutile)-water, printing ink and mayonnaise systems. Good agreements between the experiment and theory were observed.

F-109 Prevalence of pulmonary and extrapulmonary tuberculosis in patients with systemic rheumatic diseases in Korea: a national health insurance database study

( Dong Won Park ),( Misoo Chang ),( Gun Woo Koo ),( Tai Sun Park ),( Ji-yong Moon ),( Tae-hyung Kim ),( Jang Won Sohn ),( Ho Joo Yoon ),( Dong Ho Shin ),( Eun Woo Nam ),( Sang-heon Kim ) 대한결핵 및 호흡기학회 2016 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.121 No.-

Background: The increased risk of pulmonary tuberculosis (PTB) infection has been revealed among the patients with rheumatic diseases. However, it is not clear whether rheumatic diseases affect the risk of EPTB. We aimed to investigate the prevalence of both pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) in patients with rheumatic diseases. Methods: We performed analysis from the Korean Health Insurance Review and Assessment Service (HIRA) database, spanning the period from January 2012 to December 2012. The database (HIRA-NPS-2012-0090) was based on random sampling of outpatients from whole population. Patients with PTB, EPTB, and rheumatic diseases were identified based on the International Classification of Disease-10 (ICD-10) diagnostic codes. Results: We identified 30,854 (2.17%) patients with rheumatic diseases of 1,422,551 cases, and the prevalence of all forms of TB in patients with rheumatic diseases was about 3.5 times higher than those without rheumatic diseases (1.72% vs. 0.49%, respectively). In addition, prevalence of PTB and EPTB were 1.34% and 0.38% in patients with rheumatic diseases, which were almost 3-5 times higher prevalence of PTB and EPTB in those without rheumatic diseases. Conclusions: This study found that the prevalence of both PTB and EPTB were higher among the patients with rheumatic diseases. Physicians should be alert to the possibility of TB in patients with rheumatic diseases, especially EPTB.

P-148 Mediastinal lymph node metastasis without liver or lung involvement after curative resection of colon cancer

( Dong Won Park ),( Ji Hee Min ),( Gun Woo Koo ),( Yeonkyung Park ),( Tai Sun Park ),( Ji-yong Moon ),( Sang-heon Kim ),( Tae-hyung Kim ),( Jang Won Sohn ),( Ho Joo Yoon ) 대한결핵 및 호흡기학회 2017 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.124 No.-

Colon cancer usually spreads the regional lymph nodes, liver, lung, bone and brain. Metastasis to mediastinal lymph node without pulmonary and hepatic metastasis from colon cancer is very rare. Here, we report a case with multiple metastasis to mediastinal lymph nodes without any other organ involvement after curative resection of colon cancer. A 47 year-old man presented with abdominal pain, and colonoscopic biopsy were consistent with the diagnosis of colon adenocarcinoma. Subsequently, right hemicolectomy was performed, and histopathology revealed moderately to poorly differentiated adenocarcinoma of right colon with perineural and lymph vascular invasion, and metastatic involvement of 9 out of 22 regional lymph nodes. There was no distant metastasis on computed tomography scans of chest and abdomen, and the patient received chemotherapy with folinic acid, fluorouracil and oxaliplatin (FOLFOX). Two and a half years later, multiple enlarged mediastinal lymph nodes without lung and liver metastasis were observed on chest and abdomen computed tomography, and were extirpated by video-assisted thoracoscopic surgery. Pathology was consistent with the diagnosis of metastatic colonic primary adenocarcinoma. This case report suggests that the mediastinum should be considered as a possible metastatic site from colon cancer, even without evidence of lung and liver metastasis.

P-89 Emergency department visits by lung cancer patients in Korea

( Dong Won Park ),( Gun Woo Koo ),( Tai Sun Park ),( Ji-yong Moon ),( Sang-heon Kim ),( Tae-hyung Kim ),( Ho Joo Yoon ),( Dong Ho Shin ),( Jang Won Sohn ) 대한결핵 및 호흡기학회 2016 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.121 No.-

Background: We aimed to determine the frequency and main causes of emergency consultations and the predicting factors for hospital admissions and deaths. Methods: We reviewed retrospectively all the cases of ED visit for six months, from July 2014 to December 2014, in three university hospitals: Hanyang University Hospital and Chung-Ang University Hospital in Seoul, and Chungbuk National University Hospital in Cheongju using National Emergency Department Information System Database (NEDIS). We identified cases with lung cancer and performed descriptive statistics and logistic regressions analysis. Results: Of all 62,369 ED visits, there were 292 ED visit (0.47%) by 216 patients with lung cancer. Among them, 76.4% had only one ED visit in study period. The main reasons for consultation were respiratory symptoms (36.8%) and fatigue/alteration of the general state (12.7%), and pain (12.4%). ED visit leads to hospital admission in 74.9% and hospital death in 25.1% of lung cancer patients. In multivariate analysis, the main independent predictor factors of hospitalization are diagnostic phase of lung cancer (odd ratio 9.3) and the transfer from another hospital (odd ratio 4.9). The palliative phase with best supportive care alone (odd ratio 5.2) and abnormal heart rate at the time of ED visit (odd ratio 2.4) are statistically associated with death during hospitalization. Conclusions: Our study shows that ED visit is a frequent but clinically important event for patients with lung cancer.

돌출부를 지닌 전극의 전기도금시스템에 대한 이론적 이차 전류분포 해석

손태원,주재백,Sohn, Tai-Won,Ju, Jeh-Beck 한국전기화학회 2009 한국전기화학회지 Vol.12 No.4

돌출부를 지니고 있는 전극의 전기도금 공정에 대한 이론적 이차 전류분포에 대하여 고찰하였다. 전극이 모두 전도체인 경우(Case 1)와 돌출부위만 전도체인 경우(Case 2) 두 가지 경우에 대하여 인가전위, 이온교환 전류밀도와 용액의 비전도도의 비인 $\xi$값, aspect ratio의 영향 등에 대하여 살펴보았다. 그 결과 인가 전위와 $\xi$값이 증가할수록 전류분포는 불균등화가 심화됨을 알 수 있었다. Aspect ratio가 작아질수록 전류분포가 보다 균등화되며 Case 2의 경우가 Case 1의 경우 보다 균등도가 좋아짐을 알 수 있었다. 돌출부위가 다양한 모양으로 이루진 전극에 대해서도 이 모델을 적용한 결과 전극 표면에 따른 국부 전류분포를 동시에 계산할 수 있음을 알 수 있었고 이 경우에도 이전과 마찬가지로 $\xi$값이 감소할수록 전류분포의 균등도가 좋아짐을 알 수 있었다. Theoretical calculations for the secondary current distributions for the electrode with a projection part in electroplating were performed. Two kinds of electrodes were considered. One is a electrode with the overall conducting surfaces(Case 1) and the other is an electrode in which only a projection part has a conducting surface(Case 2). The effects of applied potential, the ratio of ion exchange current to conductivity, $\xi$ and the aspect ratio on the current distribution were examined. The increase of applied current or the value of $\xi$ decreased the uniformity of current distribution. The small value of aspect ratio resulted the more uniform current distribution and Case 2 showed the better uniformity than Case 2. When this model was applied into an electrode with various projection parts, the local current distribution along the electrode surface were obtained successfully. In this case, the decrease of $\xi$ also increase the uniformity of current distribution as seen previously.

알코올중독증 환자의 대뇌 국소혈류량 변화

이정태(Chung Tai Lee),손형선(Hyung-Sun Sohn),성양숙(Yang-Sook Sung),양문정(Mun-Jung Yang),채정호(Jeong-Ho Chae),박원명(Won-Myong Bahk),김광수(Kwang-Soo Kim),유태열(Tae-Yul Lew) 한국중독정신의학회 1998 중독정신의학 Vol.2 No.1

The purpose of this study was to investigate the effect of chronic alcohol intake to regional cerebral blood flow in the patients with alcohol dependence by single photon emission computerized tomography (SPECT). The subjects were detoxified alcoholic inpatients (n=10) diagnosed as alcohol dependence by DSM-IV criteria and control group (n=8). The regions of interest (ROIs) were drawn in frontal lobe (3 ROIs), temporal lobe (3 ROIs), parietal lobe (3 ROIs), occipital lobe (1 ROI), and thalamus (1 ROI). We compared data from chronic alcoholic patients to those from controls about cerebral asymmetry indices and regional cerebral blood flow (rCBF) indices measured from each ROI. The results were as follows:1) There were significant differences in asymmetry indices of thalamus with alcoholic patients and control group (p<0.05). 2) rCBF indices of alcoholic patients were significantly higher than those of control group in left posterior temporal cortex, right posterior parietal cortex and right thalamus (p<0.05), and tended strongly to be higher than those of control group in right posterior temporal cortex, left posterior parietal cortex and left superior lateral frontal cortex. The result of increased rCBF in cerebral cortex and thalamus of detoxified inpatients with alcohol dependence suggested that there may exist a significant association between alcohol dependence and frontothalamic circuitry as brain reward system. In comparison of rCBF in both hemispheres, rCBF in right thalamus was observed to increase, which is possibly associated with impulsivity and change of affective status. Further research on the change of rCBF according to the duration after alcohol withdrawal is warranted.

Risk factors of reintubation in patients receiving post-extubation nasal high flow therapy

( Yoomi Yeo ),( Tai Sun Park ),( Min Ju Jo ),( Ji-yong Moon ),( Tae-hyung Kim ),( Sung Jun Chung ),( Hyun Lee ),( Dong Won Park ),( Sang Heon Kim ),( Jang Won Sohn ),( Ho Joo Yoon ) 대한결핵 및 호흡기학회 2019 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.127 No.-

Background: Use of nasal high-low therapy (NHF) after extubation was known to lower reintubation rate. However, there are still patients undergoing reintubation despite of post-extubation NHF therapy. Purpose: The purpose of this study was to evaluate the risk factors of reintubation in patients receiving post-extubation NHF therapy. Methods: From January 2018 to June 2019, patients who underwent mechanical ventilation and NHF after extubation at Hanyang University Guri Hospital were analyzed retrospectively. All patients received adequate sedation and planned extubation was performed after passing spontaneous awakening test and spontaneous breathing test (SBT). Reintubation was performed in cases of followings: hemodynamic instability, a deterioration of neurologic status, or signs of persisting or worsening respiratory failure. Results: Of 20 patients, 6 (30%) were underwent reintubation. Patients who received reintubation had lower BMI (20.1 ± 3.4 vs. 23.4 ± 2.6, p = 0.03) compared to those who did not. There were no significant differences in age, sex, comorbidities, APACHE II score at ICU admission and day of extubation, duration of SBT, and PaO2/FiO2 ratio just before extubation. The kinds of sedatives used during mechanical respiration, the use of neuromuscular blockers, and the use of steroids prior to extubation also did not differ. However, low BMI did not show statistical significance in predicting reintubation risk in multivariate analysis (OR = 0.655, p = 0.059). Conclusion: The frequency of reintubation may be high in patients with low BMI in patients receiving NHF therapy after extubation.

벼-자운영 윤작재배에서 돈분액비 시용이 토양화학성에 미치는 영향

강세원(Se-Won Kang),서동철(Dong-Cheol Seo),서영진(Young-Jin Seo),이상규(Sang-Gyu Lee),최익원(Ik-Won Choi),전원태(Weon-Tai Jeon),강위금(Ui-Gum Kang),손보균(Bo-Kyoon Sohn),허종수(Jong-Soo Heo),조주식(Ju-Sik Cho) 한국토양비료학회 2012 한국토양비료학회지 Vol.45 No.2

벼-자운영 윤작재배에서 돈분액비의 수준별 투입이 토양화학성에 미치는 영향을 조사하였다. 시기별 토양내 주요 성분의 함량은 다소 차이는 있지만 돈분액비의 투입과 자운영의 토양 혼입으로 인해 전반적으로 유기물, 질소, 유효인산, 칼륨, 칼슘 및 마그네슘의 함량이 돈분액비 투입 23일 후까지 점점 증가하는 경향이었으며, 벼 생육이 진행될수록 토양내 질소, 유효인산, 칼륨, 칼슘 및 마그네슘의 함량이 감소하는 경향을 나타내었다. 처리구별 토양내 주요 성분의 함량은 전반적으로 돈분액비의 투입량이 많을수록 유기물, 질소, 유효인산, 칼륨, 칼슘 및 마그네슘의 함량이 높은 함량을 나타내었으며, 이에 따라 벼의 생산량도 돈분액비의 투입량에 따라 유의성 있게 증가하는 경향을 나타내어 APLM 0 처리구 대비 APLM 100 처리구에서 약 5.3% 증수효과를 보였다. 따라서 벼-자운영 윤작재배 실험 중 돈분액비의 수준별 투입은 수확량을 증대시키고 토양내에 다양한 영양분을 공급함으로써 토양의 질을 향상시킬 뿐만 아니라, 화학비료를 대체할 수 있는 방안이 될 수 있을 것으로 판단된다. This study was conducted to investigate the effect of liquid pig manure application on soil chemical properties in rice?Chinese milkvetch rotation. Field experiment was designed with APLM 0 (Chinese milkvetch + Liquid pig manure 0 L m<SUP>-2</SUP>), APLM 50 (Chinese milkvetch + Liquid pig manure 1.8 L m<SUP>-2</SUP>), APLM 75 (Chinese milkvetch + Liquid pig manure 2.7 L m<SUP>-2</SUP>) and APLM 100 (Chinese milkvetch + Liquid pig manure 3.6 L m<SUP>-2</SUP>), respectively. The concentration of O.M, T-N, Avail. P₂O5, K, Ca and Mg at different liquid pig manure levels in soil were generally high in the order of APLM 100 > APLM 75 〉 APLM 50 〉 APLM 0. Especially, T-N concentration of soil in APLM 100 was 1.4 times higher than APLM 0. The yield of rice in APLM 100 was 636 kg 10a<SUP>-1</SUP> (increasing yield 5.3%) compared with APLM 0 in rice-Chinese milkvetch crop rotation. Therefore, application of liquid pig manure was useful in rice? Chinese milkvetch crop rotation.

Dimerization of 30Kc19 protein in the presence of amphiphilic moiety and importance of Cys-57 during cell penetration

Park, Hee Ho,Sohn, Youngsoo,Yeo, Ji Woo,Park, Ju Hyun,Lee, Hong Jai,Ryu, Jina,Rhee, Won Jong,Park, Tai Hyun WILEY-VCH Verlag 2014 BIOTECHNOLOGY JOURNAL Vol.9 No.12

<P>Recently, the recombinant 30Kc19 protein, originating from silkworm hemolymph of <I>Bombyx mori</I> has attracted attention due to its cell-penetrating property and potential application as a protein delivery system. However, this observation of penetration across cell membrane has raised questions concerning the interaction of the protein-lipid bilayer. Here, we report a dimerization propensity of the 30Kc19 protein in the presence of amphiphilic moieties; sodium dodecyl sulfate (SDS) or phospholipid. Native PAGE showed that the 30Kc19 monomer formed a dimer when SDS or phospholipid was present. In the glutathione-<I>S</I>-transferase (GST) pull-down assay, supplementation of the 30Kc19 protein to mammalian cell culture medium showed dimerization and penetration; due to phospholipids at the cell membrane, the main components of the lipid bilayer. Mutagenesis was performed, and penetration was observed by 30Kc19 C76A and not 30Kc19 C57A, which meant that the presence of cysteine at position 57 (Cys-57) is involved in dimerization of the 30Kc19 at the cell membrane during penetration. We anticipate application of the native 30Kc19 protein with high cell-penetrating efficiency for delivery of cargos to various cell types. The intracellular cargo delivery using the 30Kc19 protein is a non-virus derived (e.g. TAT) delivery method, which can open up new approaches for the delivery of therapeutics in bioindustries, such as pharma- and cosmeceuticals.</P>

리튬-철 산화물 전극의 제조 및 전류전위 순환 특성에 관한 연구

정원중,주재백,손태원,Jeong Won-Joong,Ju Jeh-Beck,Sohn Tai-Won 한국전기화학회 1999 한국전기화학회지 Vol.2 No.3

본 연구에서는 리튬전지 내 양극 재료로서 리튬-철계 산화물의 응용가능성을 모색하기 위하여 여러 제조방법에 따라 변화되는 전기화학적 특성을 고찰하고자 하였다. 철산화물에 대한 기본적인 양극 전기화학적 특성을 관찰하기 위해 철판, 철분말을 산화시켜 제작한 전극과 FeOOH 분말로 제작한 전극을 전류전위 순환실험을 실행하였다. 그 결과 철판과 FeOOH분말 전극의 경우 거의 리튬 층간의 산화-환원 반응이 일어나지 않음을 알 수 있었으며 철 분말의 산화물 전극에서는 리튬이온의 환원반응 피크는 보이나 산화반응은 거의 관찰되지 않았다. 또한 출발 물질 $FeCl_3-6H_2O,\;NaOH.\;LiOH$를 혼합하여 저온으로 가열하여 층상의 $LiFeO_2$를 합성하였으며, 출발 물질의 조성비를 바꾸어 그 영향을 조사하였다. 그 결과 NaOH의 첨가량이 증가할수록 전극의 용량과 효율은 감소하나 용량의 감소율은 작아짐을 알 수 있었다. $NaOH/FeCl_3/LiOH$의 몰 비를 2/1/7로 조성하여 합성하였을 때 가장 큰 용량을 보였으나 효율은 30회 순환 후 급격히 감소하였다. Various types of iron oxide based materials as a cathode of lithium secondary battery have been prepared and their electrochemical characteristics have been also observed. In order to understand the fundamental characteristics of iron oxide electrode, three kinds of iron oxides such as iron oxides formed by direct oxidation of iron plate or iron powders and FeOOH powders were tested with cyclic voltammetry. The oxidation and reduction peaks due to the reaction of intercalation and deintercalation were not observed for the iron oxide prepared with iron plate and FeOOH powders. In case of iron oxide prepared from iron powders, only one reduction peak was observed. A layered form of $LiFeO_2$ was synthesized directly from $FeCl_3\cdot6H_2O,\;NaOH\;and\;LiOH$ and LiOH by hydrothermal reaction. The effect of NaOH on the electrode performance was examined. When increasing NaOH, it provides the electrode with less discharge capacity and efficiency, however, decreasing rate of discharge capacity became smaller. $LiFeO_2$ synthesized with the molar ratio of $NaOH/FeCl_3/LiOH$, 2/1/7 showed the largest capacity, but the discharging efficiency was sharply decreased after 30 cycles.