• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.136-146
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• 1994

To research the effect of chemotaxis of Rhizobia toward the root exudate on nitrogen fixing ability in soybean Rhizobia symbiosis system. Root exudate from seedlings of Glycine max. L was collected aseptic conditions. B. japonicum KCTC 2422 induced the formation of symbiotic nitrogen fixing nodules on the root of soybean plant and possessed motility and chemotaxis toward the 2mM proline. LPN-100 mutant was $Nod^-$, $Che^+$, and LPN-101 was $Che^-$, $Nod^+$ strains. Physiological properties of mutants were similar to parent strain. The crude root exudate was tested for its chemotactic ability using the capillary tube method. Chemotactic responses of RCR 3407 toward crude root exudate were 2.2, 2.6, 2.9, those of KCTC 2422 were 2.3, 2.9, 3.0, respectively. The crude root exudate was fractionated into neutral, cationic and anionic fractions. Chemotactic responses of KCTC 2422 was least with anionic fraction, most with neutral and intermediate with cationic fraction. B. japonicum KCTC 2422 was attracted by carbohydrates, amino acids and carboxylic acid. Carbohydrates and amino acids were good chemoattractants and carboxylic acids were intermediate chemoattractants. The peak concentration was $10^{-3}M$ for ribose, glucose, glutamine, aspartic acid and carboxylic acids, with exception of xylose, arabinose, tryptophan, which elicited maximum responses at $10^{-4}M$. The formation of nodules and nitrogenase activity of soybean inoculated with KCTC 2422 was determined in 7days after inoculation, and those of LPN-101 was detected in 15days after inoculation, but LPN-100 didn't form of nodules in soybean plants.

• Journal of Sensor Science and Technology
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• v.9 no.2
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• pp.96-105
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• 2000

Fiber optic TR-EFPI(total reflected extrtinsic Fabry-Perot interferometric) sensor was developed to measure the strain of structures, such as building, bridge, aircraft, etc. It has been difficult to distinguish the increase and decrease of the strain from the conventional fiber optic EFPI sensor because their signals only have a sinusoidal wave pattern related to the change of strain. Also, the absolute strain could not be measured by the simple fiber optic EFPI sensor. In this study, in order to measure the magnitude of strain with the direction of strain, the fiber optic sensor was simply constructed with the total reflected EFPI sensor probe. This probe was manufactured with a single mode fiber and a mirror coated fiber in a silica glass capillary tube. The output signal of this fiber optic TR-EFPT sensor can give the information about the magnitude and the direction of strain. The loading-unloading test was performed by the universal testing machine with alluminum beam specimen to compare the strain from fiber optic TR-EFPI sensor with the value from electrical strain gauge. In the result of this experiment. the strain from fiber optic TR-EFPI sensor had a good agreement with the values from the electrical strain gauge.

• Journal of Life Science
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• v.27 no.1
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• pp.78-88
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• 2017

Angiogenesis, the formation of new blood vessels, plays an important role in tumor growth and metastasis; therefore, it has become an important target in cancer therapy. Novel anticancer pharmaceutical products that have relatively few side effects or are non-cytotoxic must be developed, and such products may be obtained from traditional herbal medicines. Coptis chinensis Franch. is an herb used in traditional medicine for the treatment of inflammatory diseases and diabetes. However, potential antiangiogenic effects of C. chinensis water extract (CCFWE) have not yet been studied. The purpose of this study was to determine the antiangiogenic effect of CCFWE in order to evaluate its potential for an anticancer drug. We found that the treatment with CCFWE inhibited the major steps of the angiogenesis process, such as the endothelial cell proliferation, migration, invasion, and capillary-like tube formation in response to vascular endothelial growth factor (VEGF), and also resulted in the growth inhibition of new blood vessels in an ex vivo rat aortic ring assay. We also observed that CCFWE treatment arrested the cell cycle at the G0/G1 phase, preventing the G0/G1 to S phase cell cycle progression in response to VEGF. In addition, the treatment reduced the VEGF-induced activation of matrix metalloproteinases 2 and 9. Taken together, these findings indicate that CCFWE should be considered a potential anticancer therapy against pathological conditions where angiogenesis is stimulated during tumor development.

• Journal of Korean Traditional Oncology
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• v.11 no.1
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• pp.105-118
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• 2006

Two of the essential processes required for metastasis are neoangiogenesis and tumor cell invasion of basement membranes (BM) and extracellular matrix (ECM). Recently, data showed that herbs removing blood stasis has an anti-angiogenic effects. Tonifying vital Qi and eliminating pathogenic factor was a basic modality in Oriental oncology. In this study, we investigated several Qi and Blood tonics for potent angiogenic inhibitors. Methanol extracts of samples inhibited the proliferation of ECV-304 at the concentration of 100 ${\mu}g/m{\ell}$. Zizyphi Fructus, Glycyrrhizae Radix, Angelicae Gigantis Radix decreased the gelatinolytic activity of MMP-9 from ECV-304, at the concentration of 100 ${\mu}g/m{\ell}$ in gelatin zymography. In in vitro invasion assay, herbs inhibited the invasion activity of ECV-304 by 53% of control (Ginseng Radix), 39% (Zizyphi Fructus), 36% (Angelicae Gigantis Radix), 25% (Glycyrrhizae Radix). Ginseng Radix inhibited the capillary-like tube formation of ECV-304 at the concentration of 160 ${\mu}g/m{\ell}$, Angelicae Gigantis Radix and Paeoniae Radix Alba inhibited at the concentration of 320 ${\mu}g/m{\ell}$. These results indicated that Ginseng Radix, Glycyrrhizae Radix, and Angelicae Gigantis Radix could be considered as potent angiogenic inhibitiors.

• Analytical Science and Technology
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• v.14 no.5
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• pp.432-441
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• 2001

An automated on-line portable preconcentration-short column gas chromatograph was developed, which used preconcentrator using adsorption tube with Tenax-GR and Curie-point heating. The developed system operated with 3 steps of processing, preconcentration, thermal desorption, and analysis and cleaning, and could continued operating within 1~2 min cycle. The recoveries of preconcentrator for toluene was ranged between $94.7{\pm}6.6%$ and $103.8{\pm}3.1%$ with less than 7% of RSD. For benzene, toluene and xylene(BTX) standard gas test, IDL was 41, 49, $472ng/m^3$ benzene, toluene and o-xylene, respectively. The BTX mixture was analyzed within 30 sec with baseline separation by the system equipped with 4 m long capillary column. The deficiency of separation power caused by short column was solved by the control of sample injection volume and inlet/outlet pressure ratio. The automated portable preconcentration-short column gas chromatograph system was found to be useful for the continuous air monitoring of BTX at ppb levels in ambient air.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2011.06a
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• pp.277-277
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• 2011

본 논문은 $CO_2$ 히트펌프용 모세관의 기초 설계자료를 제공하기 위해서 모세관 길이 예측에 대해서 이론 및 실험적으로 조사하였다. 본 연구에서 고려된 작동변수로는 증발온도, 가스냉각기 냉각압력, 냉매유량, 모세관의 관경 등이다. 몇몇연구자들의 자료를 바탕으로 $CO_2$ 모세관 길이를 예측할 수 있는 수학적 모델식을 작성하였다. 그리고 단열 모세관 팽창장치내 $CO_2$의 증발온도, 냉매유량, 냉각압력 등에 대해서 실험한 결과, Fig. 1에 나타낸 것처럼, 모세관 길이가 증가할수록 증발온도는 감소하는 것을 알 수 있다. 그리고 증발온도에 대한 실험값과 예측값의 비교 결과, 실험값이 예측값보다 약간 높게 나타났다. $CO_2$냉매가 모세관내를 통과할 때 플래쉬 가스(flash gas)의 발생으로 인해 액상의 양보다 기상의 양이 많아지고 액상의 압력강하보다 기상의 압력강하가 휠씬 더 크기 때문이다. 또한 증발온도에 대한 실험값과 예측값은 6.5~9.9% 이내에서 좋은 일치를 보였다. Fig. 2에 나타낸 것처럼, 모세관 길이가 증가할수록 냉매유량은 감소하는 것을 알 수 있다. 이는 전술한 바와 같이 모세관 길이가 증가할수록 냉매 압력강하가 더욱더 증가하기 때문이다. 그리고 냉매유량에 대한 실험값과 예측값의 비교 결과, 실험값이 예측값보다 약간 높게 나타났다. 이는 전술한 증발온도와 동일한 이유로 실제 $CO_2$냉매가 모세관내를 통과할 때 플래쉬 가스의 발생량이 많아지기 때문이다. 또한 냉매유량에 대한 실험값과 예측값은 0.64~10.9% 이내에서 좋은 일치를 보였다. Fig. 3에 나타낸 것처럼, 모세관 길이가 증가할수록 냉각압력은 증가하는 것을 알 수 있다. 이는 증발온도가 일정한 경우 모세관 길이가 증가할수록 냉매유량이 감소하여 압축기 토출측 온도(압력)가 상승하기 때문이다. 그리고 냉각압력에 대한 실험값과 예측값의 비교 결과, 실험값이 예측값보다 약간 낮게 나타났으며 실험값과 예측값은 1.04~3.7% 이내에서 좋은 일치를 보였다. 따라서 본 연구에서는 수송기계용 $CO_2$ 열펌프 단열 모세관에 대한 기초설계 자료로서, 냉각압력, 증발온도, 모세관 직경, 냉매유량 등의 조건으로부터 모세관 길이를 계산해낼 수 있는 예측 상관식을 제안하였다.

• Journal of the Korean Society of Radiology
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• v.5 no.6
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• pp.409-413
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• 2011

An X-ray tube used an X-ray fluorescence analysis system has a low X-ray photon intensity which results in reducing measurement accuracy and increasing exposure time. These shortages can be overcame by using a monocapillary optics. A monocapillary optics was optimally designed for focusing the characteristic X-ray of tungsten (8.4 keV). The monocapillary optics can achieve a gain of 10 at the least. The monocapillary optics was fabricated by using puller and pyrex glass, raw material. In fabrication, a weigh of 45g and a temperature of $650^{\circ}$ was loaded. The total fabrication time was 460 minutes. The fabricated capillary had 87 mm in length and maximum diameter of 300 ${\mu}m$ and minimum diameter of 192 ${\mu}m$. When the fabricated monocapillary optics is applied to an X-ray fluorescence analysis system, the detection accuracy for soft elements, for example sulfur (S), will be improved.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.2
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• pp.113-119
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• 2006

Brazing is an important manufacturing process in the fabrication of Heavy Water Reactor fuel rods, in which bearing and spacer pads are joined to Zircaloy-4 cladding tubes. The physical vapor deposition(PVD) technique is currently used to deposit metallic Be on the surfaces of pads as a filler metal. Amorphous Zr-Be binary alloys which are manufactured by rapid solidification process are under developing to substitute the conventional PVD-Be coating. In the present study, brazed joint with PVD and amorphous alloys of $Zr_{1-x}Be_{x}(0.3{\le}x{\le}0.5)$ as filler metals are compared by mechanism, microstructure and hardness. The thickness of brazed joint with amorphous alloys became much smaller than that of PVD-Be. The erosion of base metal did not occur in the brazed joint with amorphous alloys. The brazing mechanism for PVD-Be seems to be Be diffusion into Zr-4 with capillary action resulting from eutectic reaction while that for amorphous alloys are associated with the liquid phase formation in the brazed joint. The brazed joint microstructure with PVD-Be consists of dendrite while that with amorphous alloys is globular. The $Zr_{0.7}Be_{0.3}$ alloy shows the smooth interface with little erosion in the base metal and is recommended a most suitable brazing filler metal for Zircaloy-4.

• Journal of Chest Surgery
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• v.2 no.2
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• pp.167-167
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• 1969

Two groups of esophagus graft were done in canine esophagus in 34 adult mongrel dogs. For the first group segmental replacement graft was done with fresh autologous pericardium tube, and for the second, patch graft was done utilizing fresh autologous pericardium, fresh homologous pericardium,and dacron piece. All eight dogs in the first segmental replacement graft group died 2 to 5 days after operation with severe empyema caused by anastomosis disruption. Among 26 patch graft dogs 2 died during operation and 7 died 13 to 18 days after operation. For the 17 long-term patch grafted survivors esophagography and postoperative weight check were done. Postoperative stool was collected and examined for dacron patch excretion. One, two, three, and four months postoperative long-term survivors were sacrificed to obtain specimens in each group respectively and the following observations were made.I. Survival; Autologous pericardium patch group showed no mortality but in homologous pericardium and dacron patch group only two thirds were long-term survivors. II. Postoperative swallowing; There was no case which demonstrated postoperative dysphagia. About half of the cases showed postoperative weight increase and in only 3 cases weight decrease followed operation. III. Dacron patch was excreted in the stool 8 to 23 days after operation. Animals which excreted dacron patch up to 9 days after operation all died of empyema due to anastomosis disruption.IV. Postoperative esophagogram; All esophagograms in each group showed no leakage of barium, no passage disturbances and no remarkable stenotic signs.V. Morphological findings; [A] Macroscopical findings; In one month group specimens of each group dense adhesion with surrounding structures was noted and luminal surface was smooth with contraction of the patched area. In two month groups anastomosis sutures were still exposed but patched area showed lesser abnormality. In three to four months groups sutures were covered completely and patched area showed only very slight signs of contraction. [B] Microscopic findings; In one month group luminal surface of the replaced tissue [transplanted tissue] showed almost complete epithelial covering that is composed of several layers of squamous cells with no evidence of keratinization. Basement membrane was also well distinct throughout. Slight to minimal inflammatory cells comprising of large mononuclears, lymphocytes and plasma cells were observed in the subepithelial fibrous stroma consisted entirely of loose fibrous tissue containing many newly formed capillaries and fibroblastic proliferation. Scattered suture granulomas were found, few of which became acutely inflamed. In two months group repairing process progressed with lesser degree of inflammatory cell infiltration and young capillary proliferation. Fibrous tissue was more matured showing even focal collagenization.Suture granuloma persisted but with lesser reactive changes. Epithelial covering was that of a mature non-keratinizing stratified squamous epithelium. In three and four months groups the replaced area showed essentially similar histological findings. However, subepithelial stroma still consisted entirely of connective tissue without evidence of smooth muscle regeneration. In this group, inflammatory cell infiltration was minimal or negligible. Among these patch materials autologous pericardium group showed the most satisfactory repairing process.The above mentioned results may signify the feasibility of autogenous pericardium patch graft in clinical esophageal surgery.

• Journal of Chest Surgery
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• v.2 no.2
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• pp.168-186
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• 1969

Two groups of esophagus graft were done in canine esophagus in 34 adult mongrel dogs. For the first group segmental replacement graft was done with fresh autologous pericardium tube, and for the second, patch graft was done utilizing fresh autologous pericardium, fresh homologous pericardium,and dacron piece. All eight dogs in the first segmental replacement graft group died 2 to 5 days after operation with severe empyema caused by anastomosis disruption. Among 26 patch graft dogs 2 died during operation and 7 died 13 to 18 days after operation. For the 17 long-term patch grafted survivors esophagography and postoperative weight check were done. Postoperative stool was collected and examined for dacron patch excretion. One, two, three, and four months postoperative long-term survivors were sacrificed to obtain specimens in each group respectively and the following observations were made. I. Survival; Autologous pericardium patch group showed no mortality but in homologous pericardium and dacron patch group only two thirds were long-term survivors. II. Postoperative swallowing; There was no case which demonstrated postoperative dysphagia. About half of the cases showed postoperative weight increase and in only 3 cases weight decrease followed operation. III. Dacron patch was excreted in the stool 8 to 23 days after operation. Animals which excreted dacron patch up to 9 days after operation all died of empyema due to anastomosis disruption. IV. Postoperative esophagogram; All esophagograms in each group showed no leakage of barium, no passage disturbances and no remarkable stenotic signs. V. Morphological findings; [A] Macroscopical findings; In one month group specimens of each group dense adhesion with surrounding structures was noted and luminal surface was smooth with contraction of the patched area. In two month groups anastomosis sutures were still exposed but patched area showed lesser abnormality. In three to four months groups sutures were covered completely and patched area showed only very slight signs of contraction. [B] Microscopic findings; In one month group luminal surface of the replaced tissue [transplanted tissue] showed almost complete epithelial covering that is composed of several layers of squamous cells with no evidence of keratinization. Basement membrane was also well distinct throughout. Slight to minimal inflammatory cells comprising of large mononuclears, lymphocytes and plasma cells were observed in the subepithelial fibrous stroma consisted entirely of loose fibrous tissue containing many newly formed capillaries and fibroblastic proliferation. Scattered suture granulomas were found, few of which became acutely inflamed. In two months group repairing process progressed with lesser degree of inflammatory cell infiltration and young capillary proliferation. Fibrous tissue was more matured showing even focal collagenization. Suture granuloma persisted but with lesser reactive changes. Epithelial covering was that of a mature non-keratinizing stratified squamous epithelium. In three and four months groups the replaced area showed essentially similar histological findings. However, subepithelial stroma still consisted entirely of connective tissue without evidence of smooth muscle regeneration. In this group, inflammatory cell infiltration was minimal or negligible. Among these patch materials autologous pericardium group showed the most satisfactory repairing process. The above mentioned results may signify the feasibility of autogenous pericardium patch graft in clinical esophageal surgery.