• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.10
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• pp.807-815
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• 2014

This study was performed using a laminar flow reactor that could replicate the combustion environment of pulverized coal in a blast furnace. Since a pulverized coal injection system was developed for iron making, the combustion characteristics of pulverized coal have been important in the iron and steel industry. The flame structure, particle temperature, and exhaust gas were investigated for different types of coal. The results of this study demonstrated that the combustion characteristics of coal are influenced by several properties of individual coals. In particular, the CO emission and volatile matter content of individual coals were found to have a strong influence on their combustion characteristics. Thus, this study found the properties of the coals to be significant and focused on the particle temperature and CO and $CO_2$ emissions.

• Parasites, Hosts and Diseases
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• v.35 no.4
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• pp.245-250
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• 1997

The responses of gastric mucosal mast cells (GMMCS) to infection with coccid- ian protozoa, Clptosporinium muris, in mice were examined during primary and challenge infections. Each of three-week-old ICR SPF mice was orally inoculated with a single dose of 2 × 106 oocysts of C. muffs (strain MCR). After oocyst shedding ceased, the mice were orally challenged with a single dose of 2×106 oocysts of the same species. GMMCS reached a peak on days 20-30 postinoculation (Pl) in number, and decreased thereafter. An increase on days 20-30 post-challenge-infection (PCI) was also observed. The mice showed, on the whole, normal profiles of oocyst shedding in droppings. The number of the cells of uninfected control mice remained constant. .Tudging from the above results, it is suggested that mastocytosis correlate with expulsion of C. mans in primary infection and the defense mechanism of challenge infection.

• Journal of the Korean Vacuum Society
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• v.6 no.1
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• pp.61-68
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• 1997

We examined the dependence of the growth of undoped InP epilayer by chloride vapor phase epitaxy on the growth temperature and on the $PCl_3$molar fraction. The growth temperature was varied from $620^{\circ}C$ to $650^{\circ}C$ and the $PCl_3$molar franction from $2.5{\times}10^{-2}$ to $4.5{\times}10^{-2}$. The undoped InP epilayer with hillock free surface was obtained at the growth temperature of $640^{\circ}C$ and at the PCl$_3$molar fraction of $3.0{\times}10^{-2}$. The surface morphology was improved with a decrease of the PCl$_3$molar fraction. The carrier concentration measured by Hall and ECV was less than $1{\times}10^{14}cm^{-3}$. The resistivity of the undoped InP epilayer, measured by using four probe method, showed a high value of <$3.0{\times}10^6{\Omega}\textrm{cm}$.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.16-22
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• 1994

Ninty three species of domestic weeds were collected and screened for antimicrobial, antitumor, antioxidant and herbicidal activities. Among them, few showed antifungal activities. Cuscuta japonica showed inhibitory activity against Alternaria mali, Ambrosia artemisiifolia and Geranium sibiricum against Phytophthora capsici, Aster yomema and Aster pilosus against Phytophthora parasitica. Ambrosia artemisiifolia, Artemisia princeps, Artemisia capillaris, Ludwigia prostrata, Chrysanthemum zawadskii, Bidens frondosa, and Geranium sibiricum showed broad antibacterial activities. Carex chordorhiza, Artemisia capillaris, Persicaria nodosa, Senecio koreanus, Pariicum bisulcatum, Geranium sibiricum showed antiblebbing activity on human chronic leukemia K562 cell, among them, Persicaria nodosa was the strongist. Angelica decursiva, Equisetum arvense, Cimicifuga heracleifolia, Persicaria nodosa, Geranium sibiricum, Oenothera odorata, Cyperus sanguinolentus showed antioxidant activities. Ludwigia prostrata and Peucedanum terebinthaceum showed strong herbicidal activities.

• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.3
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• pp.149-158
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• 2005

This paper describes design, fabrication, and application of the silicon based temperature controllable micro reactor. In order to achieve fast temperature variation and low energy consumption, reaction chamber of the micro reactor was thermally isolated by etching the highly conductive silicon around the reaction chamber. Compared with the model not having thermally isolated structure, the thermally isolated micro reactor showed enhanced thermal performances such as fast temperature variation and low energy consumption. The performance enhancements of the micro reactor due to etched holes were verified by thermal experiment and numerical analysis. Regarding to 42 percents reduction of the thermal mass achieved by the etched holes, approximately 4 times faster thermal variation and 5 times smaller energy consumption were acquired. The total size of the fabricated micro reactor was $37{\times}30{\times}1mm^{3}$. Microchannel and reaction chamber were formed on the silicon substrate. The openings of channel and chamber were covered by the glass substrate. The Pt electrodes for heater and sensor are fabricated on the backside of silicon substrate below the reaction chamber. The dimension of channel cross section was $200{\times}100{\mu}m^{2}$. The volume of reaction chamber was $4{\mu}l$. The temperature of the micro reactor was controlled and measured simultaneously with NI DAQ PCI-MIO-16E-l board and LabVIEW program. Finally, the fabricated micro reactor and the temperature control system were applied to the thermal denaturation and the trypsin digestion of protein. BSA(bovine serum albumin) was chosen for the test sample. It was successfully shown that BSA was successfully denatured at $75^{\circ}C$ for 1 min and digested by trypsin at $37^{\circ}C$ for 10 min.

• Analytical Science and Technology
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• v.17 no.4
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• pp.322-336
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• 2004

The improved derivatization technique of tamoxifen metabolite in human urine is described for the acylation method that they are substituted by derivatization reagent like acyl anhydride for use of gas chromatography/mass spectrometry. The hydroxyl group of tamoxifen metabolite was derivatized by trifluoroacetic anhydride (TFAA), pentafluoroacetic anhydride (PFPA) and heptaflorobutylic anhydride (HFBA). It was investigated to the gas chromatography/mass spectrometry (GC/MS) technique use negative ion chemical ionization (NCI), positive ion chemical ionization (PCI) and electron impact (EI). In acylation of the metabolites of tamoxifen, the effective reaction temperature and time were shown to be at $50^{\circ}C$ for 30 min. The 4-hydroxytamoxifen, which is known to major metabolite of tamoxifen, was not detected in human urine, whileas the hydroxymethoxytamoxifen was detected. We thought that this result was from the single dose of tamoxifen.

• Journal of the Korean Society of Radiology
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• v.17 no.4
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• pp.551-556
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• 2023

Angiography equipment is used to evaluate and treat coronary artery disease. As a common feature of equipment, radiation is used, and function development for dose reduction is being carried out by each company. Therefore, the difference depending on whether DCR installed in angiography equipment is used is analyzed from a radiological point of view to prove the effect. Among 431 patients who underwent coronary artery intervention from March 2021 to February 2023, 250 patients with retrospective data were selected. And than among the 250 subjects obtained, 91 patients used the cardiovascular roadmap function during single-vessel intervention, and 159 patients did not use the roadmap. When DCR was used, total dose area product (34.57 uGy/m² : 69.15 uGy/m²), total air kerma dose (688.47 mGy : 1640.4 mGy), fluoroscopy dose (23.87 uGy/m² : 49.91 uGy/m²) and fluoroscopy time (723.55 s : 366.03 s), total number of images (17 : 26) showed lower values and were statistically significant than those not used. The use of DCR function in single vessel coronary intervention is thought to be radiologically safer as single vessel coronary intervention using dynamic cardiovascular DCR showed lower perspective time and perspective dose than procedures performed without the DCR.

• Radiation Oncology Journal
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• v.16 no.3
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• pp.291-301
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• 1998

Purpose : A retrospective study was conducted comparing single daily fraction (SDF) thoracic radiotherapy (TRT) with twice daily (BID) TRT to determine the potential benefit of BID TRT in limited-stage small cell lung cancer (SCLC). Endpoints of the study were response. survival, pattern of failure, and acute toxicity. Materials and Methods : Between November 1989 to December 1996, 78 patients with histologically proven limited-stage SCLC were treated at the Department of Therapeutic Radiology, Chungnam National University Hospital. Of these, 9 were irradiated for palliative intent, and 1 had recurrent disease. Remaining 68 patients were enrolled in this study. There were 26 patients with a median age of 58 years, and 22 (85$\%$) ECOG performance score of less than 1 in SDF TRT. There were 42 patients with a median age of 57 years, and 36 (86$\%$) ECOG performance score of less than 1 in BID TRT By radiation fractionation regimen, there were 26 in SDF TRT and 42 in BID TRT. SDF TRT consisted of 180 cGy, 5 days a week. BID TRT consisted of 150 cGy BID, 5 days a week in 13 of 42 and 120 cGy BID, in 29 of 42. And the twice daily fractions were separated by at least 4 hours. Total radiotherapy doses were between 5040 and 6940 cGy (median, 5040 cGy) in SDF TRT and was between 4320 and 5100 cGy (median, 4560 cGy) in BID TRT. Prophylactic cranial irradiation (PCI) was recommended for patients who achieved a CR. The recommended PCI dose was 2500 cGy/10 fractions. Chemotherapy consisted of CAV (cytoxan 1000 mg/$m^2$, adriamycin 40 mg/$m^2$, vincristine 1 mg/$m^2$) alternating with VPP (cisplatin 60 mg/$m^2$, etoposide 100 mg/$m^2$) every 3 weeks in 25 (96$\%$) of SDF TRT and in 40 (95$\%$) of BID TRT. Median cycle of chemotherapy was six in both group. Timing for chemotherapy was sequential in 23 of SDF TRT and in 3 BID TRT, and concurrent in 3 of SDF TRT and in 39 of BID TRT Follow-up ranged from 2 to 99 months (median, 14 months) in both groups. Results : Of the 26 SDF TRT, 9 (35$\%$) achieved a complete response (CR) and 14 (54$\%$) experienced a partial response (PR). Of the 42 BID TRT, 18 (43$\%$) achieved a CR and 23 (55$\%$) experienced a PR. There was no significant response difference between the two arms (p=0.119). Overall median and 2-year survival were 15 months and 26.8$\%$, respectively. The 2-year survivals were 26.9$\%$ and 28$\%$ in both arm, respectively (p=0.51). The 2-rear survivals were 35$\%$ in CR and 24.2$\%$ in PR, respectively. The grade 2 to 3 esophageal toxicities and grade 2 to 4 neutropenias were more common in BID TRT (p=0.028 0.003). There was no difference in locoregional and distant metastasis between the two arms (p=0 125 and 0.335, respectively). The most common site of distant metastasis was the brain. Conclusion : The median survival and 2-year survival were 17 months and 20.9$\%$ in SDF TRT with sequential chemotherapy, and 15 months and 28$\%$ in BID TRT with concurrent chemotherapy, respectively. We did not observe a substantial improvement of long-term survival in the BID TRT with concurrent chemotherapy compared with standard schedules of SDF TRT with sequential chemotherapy. The grade 2 to 3 esophageal toxicities and glade 2 to 4 neutropenias were more common in BID TRT with concurrent chemotherapy. Although the acute toxicities were more common in BID TRT with concurrent chemotherapy than SDF TRT with sequential chemotherapy, a concurrent chemotherapy and twice daily TRT was feasible. However further patient accrual and long-term follow up are needed to determine the potential benefits of BID TRT in limited-stage SCLC.

• Microbiology and Biotechnology Letters
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• v.28 no.2
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• pp.97-104
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• 2000

Screening of Biologically Active Essential Oils from Ligusticum tenuissimum. Kim, Min-Hae, Young-Gil Kim, Jin-Ha Lee, Keo-Pyo Hong, Jung-Ki Hong, Young-Joon Kong, and Hyeon-Yong Lee*. Division of Food and Biotechnology, Kangwon National University, Chunchon 200-701, Korea, 1 Regional Crop Development Station, Kangwon Agricultural Research & Extension Services, Chunchon 200-150, Korea-The biological activities of the crude essential oils from Ligusticum tenuissimum and the control(phthalic anhydride) were compared. About 60% of the growth of MCF7, A549, and Rep3B cells were inhibited by adding 1.0 mg/ml of the crude essential oils and below 40% was observed by the control. Cytotoxicity on human normal lung cell(IMR90) was scored as 34.4% for the crude oil and 26.4% for control, respectively. It was found that the crude essential oils were more effective than the control in anti mutagenecity tested by both Rec-assay and CRG V79 cells. The growth of human T-cell(Jurkat) was enhanced up to 1.21 times by adding the crude essential oil compared with the control. 50% of a-glucosidase activity was inhibited by both the crude essential oil and the control. ACE activities were inhibited 80.1 % and 65.3% by adding 1.0 mg/ml of the crude oil and the control, respectively. The higher enhancement of glutathione-S-transferase activity was observed in the crude oil than those in the control: 301 % v.s 234% at 1.0 mg/ml of the treatment. Thrombolytic activity was measured as 42.9% and 28.6% for the crude oil and the standard, respectively. The effect of the oil on the nerve cells PCI2, was observed as follows: the neurite of PCl2 cells was lengthened up to 255 /-lm longer than 205 /-lm of control. The number of neurite-bearing cells were about two times higher than control. The survival ratio of the crude essential oil was also increased up to 56.4% which was about two fold higher than in control.

• The Korean Society of Law and Medicine
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• v.18 no.2
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• pp.163-194
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• 2017

Coronary artery disease has increased in Korea as the country enters the aged society. It is well known that the incidence of coronary artery disease is related to aging, hypertension, diabetes, hyperlipidemia, and dietary habit. For effective treatment of significant coronary stenosis, close coordination between cardiac surgery and cardiology team is essential. Especially cardiologists' decision whether to do the stent placement or CABG is very important because the cardiologists usually start to consult the patients for their treatment. Recently, non-surgical interventions(that is stent placement) in cardiology field have dramatically increased as the national insurance system removed the limitation of the number of stents deployed. However, accidents are often caused by inappropriate use of stents, especially in patients with triple coronary disease or left main disease with heavy coronary calcifications. Another aspect of stent placement is to cope with an emergency case in the event of coronary rupture or pericardial tamponade during coronary interventions without cardiac surgeons. In the past two years, the Korea Consumer Agency (Consumer Dispute Coordination Committee) analyzed eight cases of medical dispute settlement. Only two hospitals were manned with both cardiologists and cardiac surgeons. Seven patients died of procedures of stenting and five patients died on the day of the procedure. Among the 8 cases, 5 cases showed 3 vessel disease and the rest of the cases had either severe calcification, complete occlusion or poor coronary antomies for stenting According to a 2017 national data registry of coronary stenting, less than 3 drug-eluting stents were implanted in 98% of all patients. In 2015, the number of stent procedures was 38,922, and approximately in 800 (2%) cases, more than four stents were used per patient. We emphasize that it is necessary to seriously consider the cost-benefit analysis between stent and CABG. The patient has the right to choose the right procedure by asking the liability of 'instruction explanation obligation'. He should be well informed of the pros and cons of both procedures to avoid overuse of stent. It can be solved by intimate discussion of individual cases with the cardiac surgeon and the patient. Unilateral dialogue with the patient, forceful restriction on the number of stenting, lack of surgeon's backup in difficult cases should all be avoided. It is also necessary to solve the problem not only at the hospital level, such as multidisciplinary integrated medical care, but also a nationwide solution such as expanding cardiac surgeons as essential personnel to public officials.