• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.13-26
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• 1968

To establish the most efficient method of nitrogen and phosphorus fertilization in paddy rice a series of internationally coordinated research using $N^{15}\;P^{32}$ isotopes were carried out from the year 1962 through 1967, supervised by the Joint FAO/IAEA Division of Atomic Energy in Agriculture under the auspicies of FAO, UN. In Korea College of Agriculture, Seoul National University had been participated in the Coordinated Research Programme from the year 1963 through the last year, arid the results obtained through the six years' researches are summarized as follows: 1. In the application of superphosphate broadcasting or placement at the surface of paddy as basal dressing was most efficient. 2. Split or late application of superphosphate did not affect the grain yield of the rice, but its efficiency in the rice plant uptake was less than in the case of basal dressing of whole amounts. 3. The contents of available soil phoshorus of the experimental sites in Korea were above 60 ppm, and the efficiency of phosphorus utilization of the rice from the fertilizer was approximately 10 per cent. The grain yield response of the rice to phosphorus application in Korea was rather small comparing to those of other countries. 4. The nitrogen uptake of the rice plants from the fertilizer was most efficient when the fertilizer was applied at the time of ear prime growth. However, the most efficient utilization of nitrogen did not necessarily accompany the maximum yield of the rice and basic application of adequate amount of nitrogen was required to secure proper number of panicles. 5. In the application of nitrogenous fertilizer shallow placement at 5 cm depth was most efficient. The effect of split application of nitrogen was not so noticeable. It seemed due to the fact that total application amount of nitrogen, 60 kg N/ha, was smaller than that of usual dosage in Korea. 6. The efficiency of nitrogen utilization of the rice from the fertilizer was about 40 percent in Korea, and the yield reponse of the rice plant to nitrogen application was remarkable comparing to those of other countries, showing the marked differences in the fertilizer efficiency and grain yield according to the application method. 7. The nitrogen uptake of the rice plant was not likely affected by the time and the rate of phosphorus application whereas the efficiency of phosphorus utilization was affected to some degree by the method of nitrogen application.

• Journal of Chest Surgery
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• v.41 no.1
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• pp.12-24
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• 2008

Background: It is currently thought that tissue valve degeneration is related to an animal's immune response, which is mainly due to cell surface ${\alpha}$-Gal epitopes. Cell surface ${\alpha}$-Gal epitopes are known to be degraded by the enzyme called green coffee bean ${\alpha}$-Galactosidase. It is also well known that ${\alpha}$-Gal epitopes are immunologically stained by Griffonia Simplicifolia isolectin type B4. We know that many commercially available tissue valves are made of aortic valves and pericardial tissue of pig. So, we investigated whether ${\alpha}$-Gal epitopes of the aortic valve and pericardial tissue of a pig can be removed by green coffee bean ${\alpha}$-Galactosidase, and we did so by comparing immunologic staining of the tissues before and after the enzyme treatment. Material and method: After treating fresh porcine aortic valve and pericardial tissue with green coffee bean ${\alpha}$-Galactosidase at concentrations of 0.5 unit/mL, 1.0 unit/mL, 2.0 unit/mL, respectively, under the condition of pH 6.5, temperature. $4^{\circ}C$ and 24 hours of incubation, each sample was stained with Griffonia Simplicifolia isolectin type B4 immunpfluorescent labeling. We then examined whether the ${\alpha}$-Gal epitopes were reduced or abolished in each consecutive. concentration of green coffee bean ${\alpha}$-Galactosidase by comparing the degree of the Griffonia Simplicifolia isolectin B4 staining in each sample. Result: In the pig aortic valve tissue, a 1.0 unit/mL concentration of green coffee bean ${\alpha}$-Galactosidase at pH 6.5, $4^{\circ}C$ and reaction for 24 hours was enough for complete removal of ${\alpha}$-Gal epitopes from the cell sur face on the immunostaining with Griffonia Simplicifolia isolectin B4. On the other hand, more ${\alpha}$-Gal epitopes were present in the pig pericardial tissue on Griffonia Simplicifolia isolectin B4 staining before the enzyme treatment, and 1.0 unit/mL of galactosidase was not sufficient for complete removal of ${\alpha}$-Gal from the tissue. 2.0 units/mL of green coffee bean ${\alpha}$-Galactosidase was needed to completely remove the ${\alpha}$-Gal epitopes from the pericardial tissue on immunostaining. Conclusion: The ${\alpha}$-Gal epitopes of the pig's aortic valve and pericardial tissue were successfully stained with Griffonia Simplicifolia isolectin B4. We could remove nearly all the ${\alpha}$-Gal epitopes using green coffee bean ${\alpha}$-Galactosidase at the concentration of 1.0 unit/mL in the aortic valve. Of pig, and 2.0 unit/mL was need to nearly completely remove all the ${\alpha}$-Gal epitopes in the pericardial tissue of pig under the condition of pH 6.5, $4^{\circ}C$ and 24 hours of reaction time. In the near future, removal of ${\alpha}$-Gal epitapes in the pig's aortic valve and pericardial tissue will become a powerful tool for the improvement of the tissue valve durability. It needs to be determined if ${\alpha}$-galactosidase treated pig tissue is immune to human anti-Gal antibody or anit-Gal mooclonal antibodies.

• Journal of Chest Surgery
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• v.38 no.12 s.257
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• pp.807-814
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• 2005

Background: Cardiopulmonary bypass is an essential process to maintain circulation for saving life during the cardiac surgery, But it is a process in which systemic inflammation was evoked inevitably because of the exposure of blood to foreign surface. The injuries to distal organs during the cardiopulmonary bypass were resulted from systemic inflammation and the disturbances of micro-circulations in the organs. We designed this study to research the effects of leukocyte depletion from pump-oxygenator priming solution on the systemic inflammation, and the micro-circulation of gastric mucosa that is suggested by the gastric mucosal $CO_{2}$ partial pressure and acidity. Material and Method: The dogs were divided into three groups according to the different pump-oxygenator priming solutions; non-hemic crystalloid solution; leukocyte-depleted homologous blood; and non leukocyte-depleted homo-logous blood. Each priming solution group contained five dogs. In all three groups, 2 hours of cardiopulmonary bypass, and 4 consecutive hours of general anesthesia was maintained on the mechanical ventilation. Each dog was evaluated for the gastric mucosal pH, $CO_{2}$ partial Pressure, arterial pH, $CO_{2}$ partial pressure, the exhaled air $CO_{2}$ partial pressure and the level of IL-8 on before the cardiopulmonary bypass, 1 hour after the cardiopulmonary bypass, 2 hours after the cardiopulmonary bypass, 2 hours after the restoration of normal circulation, and 4 hours after the restoration of normal circulation after the cardiopulmonary bypass. The levels of IL-8 were measured with ELISA (enzyme linked immunosorbent assay) technique. Result: 1. There were significant differences of gastric mucosal $CO_{2}$ partial pressure between the leukocyte-depleted homologous blood group and other two groups(vs non leukocyte-depleted homologous blood group; P=0.02, vs non-hemic crystalloid solution group; P=0,01). 2. The gastric mucosal pH of leukocyte-depleted homologous blood group was significantly different from non leukocyte-depleted homologous blood group (p=0.01). 3. The levels of IL-8, which examine the systemic inflammation, showed signi- ficantly better results in leukocyte-depleted homologous blood group and non-hemic crystalloid solution group than non leukocyte-depleted homologous blood group (p=0.01, 0.01). Conclusion: Based upon these results, we concluded that the leukocyte depletion from the pump-oxygenator priming solution has a beneficial effects in reducing systemic inflammation and the preserving of gastric mucosal micro-circulation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.1
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• pp.1-7
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• 2002

To study the increased resistance in fish against Vibrio vulnificus known as an important agent of vibrio septicemia in human, we analyzed specific and nonspecific immune response in flounder after administration of V. vulnificus bacterins by oral route. It contained the comparison of antibody concentrations in the sera of flounder after oral administration by two different protocols with uncoated heat killed bacterin of V vulnificus (UHKB, 20 mg/kg body weight), i.e., 4 weeks continuously (group 4W) and taking 2 weeks resting period between the 1st and last week of administration (group 1-2-1W). Even though, 1-2-1W group showed significantly increased level of specific antibody in serum, it did not reach to that of 4W group. Certainly, flounder vaccinated twice a week for four weeks (20 mg/kg b.w.) showed increased concentration of specific antibody against V. vulnificus at week 2 after last administration by oral route and maintained throughout the experimental period. It also was confirmed by the increased numbers of specific antibody secreting cells (SASC) in the leukocytes isolated from the splenocytes of the flounder of 4W group at week 1 after last administration until the end of experimental period. However, enteric, acid-resistant film coated heat killed bacterin (ECHB) did not show both greater immune reaction for antibody production and faster elimination of a challenge dose of V. vulnificus compared with those of the UHKB. These results suggested that UHKB administered by oral route was very effective method to prevent the contamination of V vulnificus in flounder, and did not show the increased antigenicity by coating the surface with acid-resistant film.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.762-767
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• 2009

In this study, the feasibility of using vegetable oil extracted from tropical crop seed as a biodiesel feedstock was investigated by producing biodiesel and analysing the quality parameters as a transport fuel. In order to produce biodiesel efficiently, two step reaction process(pre-treatment and transesterificaion) was required because the tropical crop oil have a high content of free fatty acids. To determine the suitable acid catalyst for the pre-esterification, three kinds of acid catalysts were tested and sulfuric acid was identified as the best catalyst. After constructing the experimental matrix based on RSM and analysing the statistical data, the optimal pre-treatment conditions were determined to be 26.7% of methanol and 0.982% of sulfuric acid. Trans-esterification experiments of the pre-esterified oil based on RSM were carried out, then discovered 1.24% of KOH catalyst and 22.76% of methanol as the optimal trans-esterification conditions. However, the quantity of KOH was higher than the previously established KOH concentration of our team. So, we carried out supplemental experiment to determine the quantity of catalyst and methanol. As a result, the optimal transesterification conditions were determined to be 0.8% of KOH and 16.13% of methanol. After trans-esterification of tropical crop oil, the produced biodiesel could meet the major quality standard specifications; 100.8% of FAME, 0.45 mgKOH/g of acid value, 0.00% of water, 0.04% of total glycerol, $4.041mm^2/s$ of kinematic viscosity(at $40^{\circ}C$).

• Radiation Oncology Journal
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• v.17 no.4
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• pp.299-306
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• 1999

Purpose : The human genetic disorder ataxia-telangiectasia (AT) is a multisystem disease characterized by extreme radiosensitivity. The recent identification of the gene mutated in AT, ATM, and the demonstration that it encodes a homologous domain of phosphatidylinositol 3-kinase (PI3-K), the catalytic subunit of an enzyme involved in transmitting signals from the cell surface to the nucleus, provide support for a role of this gene in signal transduction. Although ionizing radiation was known to induce c-fos transcription, nothing is known about how ATM or PKCI mediated signal transduction pathway modulates the c-fos gene transcription and gene expression. Here we have studied the effect of PKCI on radiation sensitivity and c-fos transcription in normal and AT cells. Materials and Methods: Normal (LM217) and AT (AT5BIVA) cells were transfected with PKCI expression plasmid and the overexpression and integration of PKCI was evaluated by northern blotting and polymerase chain reaction, respectively. 5 Gy of radiation was exposed to LM and AT cells transfected with PKCI expression plasmid and cells were harvested 48 hours after radiation and investigated apoptosis with TUNEL method. The c-fos transcription activity was studied by performing CAT assay of reporter gene after transfection of c-fos CAT plasmid into AT and LM cells. Results: Our results demonstrate for the first time a role of PKCI on the radiation sensitivity and c-fos expression in LM and AT cells. PKCI increased radiation induced apoptosis in LM cells but reduced apoptosis in AT cells. The basal c-fos transcription activity is 70 times lower in AT cells than that in LM cells. The c-fos transcription activity was repressed by overexpression of PKCI in LM cells but not in AT cells. After induction of c-fos by Ras protein, overexpression of PKCI repressed c-fos transcription in LM cells but not in AT cells Conclusion: Overexpression of PKCI increased radiation sensitivity and repressed c-fos transcription in LM cells but not in AT cells. The results may be a. reason of increased radiation sensitivity of AT cells. PKCI may be involved in an ionizing radiation induced signal transduction pathway responsible for radiation sensitivity and c-fos transcription. The data also provided evidence for novel transcriptional difference between LM and AT cells.

• Progress in Medical Physics
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• v.19 no.1
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• pp.73-79
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• 2008

Retinal prosthesis is regarded as the most feasible method for the blind caused by retinal diseases such as retinitis pigmentosa (RP) or age related macular degeneration (AMD). Recently Korean consortium launched for developing retinal prosthesis. One of the prerequisites for the success of retinal prosthesis is the optimization of the electrical stimuli applied through the prosthesis. Since electrical characteristics of degenerate retina are expected to differ from those of normal retina, we performed voltage stimulation experiment both in normal and degenerate retina to provide a guideline for the optimization of electrical stimulation for the upcoming prosthesis. After isolation of retina, retinal patch was attached with the ganglion cell side facing the surface of microelectrode arrays (MEA). $8{\times}8$ grid layout MEA (electrode diameter: $30{\mu}m$, electrode spacing: $200{\mu}m$, and impedance: $50k{\Omega}$ at 1 kHz) was used to record in-vitro retinal ganglion cell activity. Mono-polar electrical stimulation was applied through one of the 60 MEA channel, and the remaining channels were used for recording. The electrical stimulus was a constant voltage, charge-balanced biphasic, anodic-first square wave pulse without interphase delay, and 50 trains of pulse was applied with a period of 2 sec. Different electrical stimuli were applied. First, pulse amplitude was varied (voltage: $0.5{\sim}3.0V$). Second, pulse duration was varied $(100{\sim}1,200{\mu}s)$. Evoked responses were analyzed by PSTH from averaged data with 50 trials. Charge density was calculated with Ohm's and Coulomb's law. In normal retina, by varying the pulse amplitude from 0.5 to 3V with fixed duration of $500{\mu}s$, the threshold level for reliable ganglion cell response was found at 1.5V. The calculated threshold of charge density was $2.123mC/cm^2$. By varying the pulse duration from 100 to $1,200{\mu}s$ with fixed amplitude of 2V, the threshold level was found at $300{\mu}s$. The calculated threhold of charge density was $1.698mC/cm^2$. Even after the block of ON-pathway with L-(1)-2-amino-4-phosphonobutyric acid (APB), electrical stimulus evoked ganglion cell activities. In this APB-induced degenerate retina, by varying the pulse duration from 100 to $1200{\mu}s$ with fixed voltage of 2 V, the threshold level was found at $300{\mu}s$, which is the same with normal retina. More experiment with APB-induced degenerate retina is needed to make a clear comparison of threshold of charge density between normal and degenerate retina.

• Journal of Navigation and Port Research
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• v.42 no.4
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• pp.245-252
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• 2018

A method of transmitting an alert signal in case of man-overboard (MOB) systems in a small fishing vessel navigating within coastal area is being operated as VHF-DSC equipment via a distress alert button and V-P ass Equipment via alert button or beacon separation. However, a small fishing vessel with a couple of crews on board is an inappropriate way to alert a man-overboard condition. However, internationally, MOB equipment using VHF-DSC, AIS, and Bluetooth technologies is used to transmit alert signals directly to the mother ship and other radio stations. In order to analyze the performance and technology of the MOB equipment operating in foreign countries, it was confirmed that the alarm signal can be received within a maximum of one nautical mile when the MOB device is on the water surface. An MOB device that meets domestic conditions needs to send an alarm signal to a station within the VHF communication range. However, in order to reduce the false alert signal, it is most appropriate to operate the VHF-DSC radio equipment installed on the ship remotely. Analysis of various technologies connecting the MOB and the VHF-DSC revealed that the Bluetooth system has advantages such as device miniaturization. When an emergency signal is transmitted from the MOB device, it can be received by a dedicated receiver and recognized through an external input terminal of the VHF-DSC equipment generating its own alarm. If the emergency situation cannot be processed at the mother ship, a distress alert is sent to all radio stations via VHF-DSC for response under emergencies faced by small fishing vessels.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1081-1090
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• 2017

The purpose of this study was to develop a functional porridge prepared with mulberry leaf and mulberry fruit powder, which can ameliorate hypertension. The experiment was designed according to the central composite design. For optimization of the mixture ratio of mulberry leaf powder (MLP) and mulberry fruit powder (MFP), the independent variables were defined as MLP (X1) and MFP (X2) and the dependent variables were defined as K (Y1), Na (Y2), ${\gamma}$-aminobutyric acid (GABA) (Y3), cyanidin-3-glycoside (C3G) (Y4), rutin (Y5), and flavonoid (Y6). The optimal MLP to MFP mixture ratio according to the response surface method were 5.41 g of MLP and 2.65 g of MFP. The amounts of K, Na, GABA, C3G, rutin, and flavonoid in the optimal MLP and MFP mixture were 1,844.22 mg/100 g, 52.74 mg/100 g, 139.98 mg/100 g, 1,134.89 mg/100 g, 101.56 mg/100 g, and 201.28 mg/100 g, respectively. The amounts of Ca, K, Mg, and Na in the functional porridge at this optimal point were 27.66 mg/100 g, 131.32 mg/100 g, 19.57 mg/100 g, and 3.59 mg/100 g, respectively. Overall, this functional porridge can help reduce hypertension.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.217-225
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• 2004

This study was carried out to reduce the loss of frozen dough quality during frozen storage. Using response surface method, ascorbic acid 160.4 ppm, L-cysteine 63.1 ppm, and SSL 0.6% were found to be optimum, with xanthan gum 0.3% (formula A) and Ultra tex-3 5% (formula B) added as cryoprotectants. During frozen storage at $-20^{\circ}C$, control rapidly deteriorated after 4 weeks, while formulas A and B showed slight deterioration with immutable quality after 10 weeks.