• Applied Biological Chemistry
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• v.39 no.3
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• pp.189-194
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• 1996

The effects of scorpion (Leiurus quinquestriatus hebraeus, Lqh) venom were evaluated on the activities of microsomal $Ca^{2+}-ATPase$ and $Ca^{2+}$ release channel prepared from the epithelial cells of pig airway. Whole venom of Lqh $(120\;{\mu}g/ml)$ increased the activity of microsomal $Ca^{2+}-ATPase$ about 32% in the tight-sealed microsomes and about 28% in the Triton X-100-treated or $Ca^{2+}$ ionophore A23187-treated leaky microsomes. Thapsigargin, a specific antagonist of $Ca^{2+}-ATPase$, inhibited 42% of total ATPase activity and also completely blocked the effects of Lqh venom, suggesting that Lqh venom directly activiates the microsomal $Ca^{2+}-ATPase$. In order to determine if Lqh venom increases the microsomal uptake of $^{45}Ca^{2+}$, Lqh venom was added in the uptake medium. The Lqh venom increased microsomal $^{45}Ca^{2+}$ uptake up to ${\sim}20%$ and the increase was only observed when heparin, an antagonist of $InsP_3$ receptor channel, was added in the uptake medium. Lqh venom in the absence of heparin unexpectedly decreased the rate and the amount of $^{45}Ca^{2+}$ uptake. These results were explained by simultaneous increases in $^{45}Ca^{2+}$ release as well as $^{45}Ca^{2+}$ uptake by Lqh venom. Lqh venom itself increased the release of $^{45}Ca^{2+}$ as much as $^{45}Ca^{2+}$ release by $4\;{\mu}m\;InsP_3$, implying that Lqh venom also activates $InsP_3$ receptor, microsomal $Ca^{2+}$ release channel. Based on these results, we suggest that the Lqh venom consists of at least two components; one activates the $InsP_3$ receptor and the other avates the $Ca^{2+}-ATPase$. Currently we a investigating the chemical and electrophysiological properties of the active components of Lqh venom.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.73-83
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• 1993

The purpose of this study was to evaluate the effect of various acid treatments on dentin bonding. Freshly extracted human teeth were uprightly embedded in self curing acrylic resin, and their occlusal surfaces were grinded to expose flat dentin surfaces. The specimens were divided into 4 groups. Specimens of one group were not treated so as to be a control and those of the other three groups were threated with 10% polyacrylic acid, 10% phosphoric acid, and 10-3 solution(10% citric acid/3% ferric chloride) respectively. Primer, bonding resin and composite resin were applied over the treated dentin surfaces sequentially. All specimens were stored in $37^{\circ}C$ distilled water for 24 hours, then the tensile bond strength was measured and the treated dentin surfaces and fracured dentin surfaces were examined under a scanning electron microscope. The results were as follows: Bond strengths of acid-treated groups were higher than those of the untreated group. In the acid-treated groups, bond strength was found to be the highest in the 10-3 solution group followed by the 10% phosphoric acid group and the 10% polyacrylic acid group(P<0.01). On SEM examination of dentin surfaces, the untreated dentin surface showed a remaining smear layer and closed dentinal tubules. Dentin surfaces treated with 10 % polyacrylic acid showed a clean dentin surface without the smear layer, but showed remaining smear plugs in dentinal tubules. A dentin surface treated with 10% phosphoric acid or 10-3 solution showed open dentinal tubules without the smear layer or smear plugs. On SEM observation of the fractured dentin-resin interface, the untreated group showed that failure occurred in the smear layer. The group treated with 10% polyacrylic acid showed no resin tag remained in the dentinal tubules, but resin tags in the dentinal tubules were observed in the group treated with the 10% phosphoric acid or the 10-3 solution. On the failure mode examination, the higher the bond strength of the group, the higher the frequency of cohesive failure. The coefficient between bond strength and cohesive failure rate was 0.71.

• Korean Journal of Veterinary Research
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• v.25 no.1
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• pp.7-17
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• 1985

Many investigators have been pursuing various attempts so far to produce hepatitis B surface antigen(HBsAg) vaccines using the techniques such as isolation from plasma of chronic HBsAg carrier, recombinant DNA technique or preparation of synthetic peptides specific for immunogenic determinants. Hepatitis B virus can not grow on any cell lines by the tissue culture technique at the present time. The plasma of chronic HBsAg carrier is expensive and its source is limited. The HBsAg from the recombinant DNA technique gave still very low yield. Another approach, therefore, has been initiated to develop a synthetic hepatitis B virus vaccine. The possible use of several distinct synthetic vaccines in prophylaxis can be facilitated by availability of full synthetic immunogens. Peptides synthesized for potential application as antiviral vaccines have been mostly tested in the form of conjugates with carrier proteins, although the free synthetic peptide can be immunogenic. To understand basic knowledges on the antigenicity and immunogenicity of a synthetic peptide specific for major immunogenic determinant of HBsAg, a nonapeptide, $H_2N^{139}Cys-Thr-Lys-Pro-Thr-Asp-Gly-^{146}Asn-Aba$ COOH, which corresponds to HBsAg amino acid residues 139 to 147, was synthesized by the Merrifield's solid-phase method with a slight modification. The antigenicity and immunogenicity of this specific synthetic peptide were examined comparing with purified plasma-derived natural HBsAg. The results obtained are as follows; 1. The peptide synthesized showed the identical amino acid composition to the theoretical value. The degree of purification and molecular weight were acertained by methods of high performance liquid chromatography and mass spectrometry. 2. Using m-maleimidobenzoyl-N-hydroxysuccinimide ester as a conjugating agent, the synthetic peptide was conjugated to rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin. Their conjugation yields were 8.3, 9.5, 15.8, 13.5, and 11.2%, respectively. 3. The natural HBsAg was purified from plasma of chronic HBsAg carrier. By the electron microscopic observation of the purified natural HBsAg preparation, no Dane particles were observed and the preparation showed negative DNA polymerase activity. 4. Antigenicity of the synthetic peptide and the plasma-derived natural HBsAg was determined by competition radioimmunoassay using $^{125}I$-natural HBsAg. Their 50% inhibitions appeared as $90{\mu}g/ml$ and $0.12{\mu}g/ml$ for the synthetic peptide and the natural HBsAg, respectively. This indicates that the former was about 750-fold less antigenic than the latter. 5. Immunogenicity of the synthetic peptide was determined by administering the peptide-carrier conjugates into rabbits with and without Freund's complete adjuvant. Regardless the carrier proteins and adjuvant, positive immune responses to the synthetic peptide were observed. The higher antibody titers, however, were shown in the groups administered with Freund's complete adjuvant. 6. Immunizing dose 50% in mice of the various peptide-carrier conjugates was 5.47, 6.00, 65.16, 31.25 and $13.03{\mu}g/dose$ for rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin, respectively, while the natural HBsAg showed $0.65{\mu}g/dose$. 7. It was postulated that homologous proteins prefer to heterologous ones as the carriers.

• The Korean Journal of Petroleum Geology
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• v.2 no.2 s.3
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• pp.51-57
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• 1994

Analysis of the aeromagnetic data aquired by US Navy in the year 1969 permits us to predict a new sedimentary basin, Heugsan Basin, south of the known Gunsan Basin in Block Ⅱ. The basin appears to consist of three sub-basins trending NNW-SSE. The results of our analysis provide not only an independent assessment of the Gunsan Basin, but also new important information on the tectonic origin and mechanism for the two basins as well as for the entire region. The basin forming tectonic style is interpreted as rhombochasm associated with double overstepped left-lateral wrench faults. From the magnetic evidence, a few NE-SW trending major onshore faults are extended to the study area. We also interpreted the nature of the faults to be left-lateral wrenches. This new gross structural style is consistent with the results of recent Yeongdong Basin analysis by Lee. The senses of fault movement are also supported by the paleomagnetic evidence that the Philippine Sea had experienced an 80-degree clockwise rotation since the Eocene. Based on a 2 $\frac{1}{2}$ model study the probable maximum thickness of the sediments in the Gunsan Basin is approximately 7500 meters. We believe that the new Heugsan Basin was left unidentified because a high velocity layer may be overlying the basin. Because the overall structural configuration of the Heugsan Basin appears to be favorable for hydrocarbon accumulation, a detailed airborne magnetic survey is recommended in the area in order to verify the magnetic expression of this thick basin. A detailed subsequent marine gravity survey is also recommended in order to delineate the sedimentary section and to acquire supplemental data to the magnetic method only if an overlying high velocity layer is confirmed. Otherwise a high energy source seismic survey may be more effective.

• The Korean Journal of Nuclear Medicine
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• v.33 no.4
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• pp.422-429
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• 1999

Purpose: The measurement of radiation absorbed dose is useful to predict the response after I-131 labeled metaiodobenzylguanidine (MIBG) therapy and determine therapy dose in patients with unresectable or malignant pheochromocytoma. We estimated the absorbed dose in tumor tissue after high dose I-131 MIBG in a patient with pheochromocytoma using a gamma camera and Medical Internal Radiation Dose (MIRD) formula. Materials and Methods: A 64-year old female patient with pheochromocytoma who had multiple metastases of mediastinum, right kidney and periaortic lymph nodes, received 74 GBq (200 mCi) of I-131 MIBG. We obtained anterior and posterior images at 0.5, 16, 24, 64 and 145 hours after treatment. Two standard sources of 37 and 74 MBq of I-131 were imaged simultaneously. Cummulated I-131 MIBG uptake in tumor tissue was calculated after the correction of background activity, attenuation, system sensitivity and count loss at a high count rate. Results: The calculated absorbed radiation dose was 32-63 Gy/ 74 GBq, which was lower than the known dose for tumor remission (150-200 Gy). follow-up studies at 1 month showed minimally reduced tumor size on computed tomography, and mildly reduced I-131 MIBG uptake. Conclusion: We estimated radiation absorbed dose after therapeutic I-131 MIBG using a gamma camera and MIRD formula, which can be peformed in a clinical nuclear medicine laboratory. Our results suggest that the measurement of radiation absorbed dose in I-131 MIBG therapy is feasible as a routine clinical practice that can guide further treatment plan. The accuracy of dose measurement and correlation with clinical outcome should be evaluated further.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.3
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• pp.187-194
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• 1985

This field experiment was carried out to determine the effects of thirteen different fertilizer levels of nitrogen(N), phosphorus($P_2O_5$) and potassium($K_2O$) on the content of crude protein, crude fiber, mineral constituents of product and tree growth forest pasture with 40-50% shading. The experiment was arranged as a randomized block design and performed in the suburban forest of Suweon in 1984. The results obtained are summarized as follows: 1. Crude protein content and total protein yield were higher in the plot of 28 and 42kg $N/_{10a}$, regardless of $P_2O_5\;and\;K_2O$ level, while those were the lowest in zero fertilizer and N-zero fertilizer plots. 2. The contents of lignin and silica were significantly low in the high N fertilizer level, and the contents of NDF, ADF, cellulose and hemicellulose were not affected by different fertilizer levels. However, the content of crude fiber tended to be low with high N, regardless of $P_2O_5\;and\;K_2O$. 3. The contents of N,K and $SiO_2$ of grasses were influenced by different fertilizer levels. However, those of P,Ca,Ma and Na showed little differences. 4. The recovery percentage of NPK was higher in the plot of standard fertilizer level with 28-20-24 kg/10a, and higher recovery percentage was observed in $K_2O$, followed by N and $P_2O_5$ in that order. 5. The growth of tree was increased as the level of N fertilizer was increased, but no such trend was noted by $P_2O_5\;and\;K_2O$ levels. 6. Crude protein, crude fiber, some mineral contituents of grasses, and growth of tree were influenced by N level, regardless of $P_2O_5\;and\;K_2O$. And the optimum fertilizer level of $N-P_2O_5-K_2O$ seemed to be 28-20-24 kg/10a for the production of grasses with higher quality and more yield in the forest.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.39-44
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• 2014

This study was conducted to investigate the effect of the addition of lactic acid bacteria (LAB) and chlorella on the change of nutritive value, quality and microbes regarding the mixture silage of Italian ryegrass and hairy vetch (IRG-HV silage). The content of crude protein of IRG-HV silage in only the LAB treatment was not different as compared to the control. However, the content of crude protein significantly increased in the treatment of LAB with chlorella, compared to both the control and LAB treatments (p<0.05). Acid detergent fiber, neutral detergent fiber, total digestible nutrient and in vitro dry matter digestibility of IRG-Alfalfa silage were not significantly different in all treatments. Further, the pH of IRG-HV silage in only the LAB treatment was not different as compared to control, but decreased in both LAB and chlorella treatments (p<0.05). The content of lactic acid in the LAB treatment increased as compared to the control, and also significantly increased in the LAB treatment with chlorella (p<0.05). In addition, the number of LAB in LAB treatment increased as compared to the control, and significantly also increased in the LAB treatment with chlorella (p<0.05). Therefore, we suggest that IRG-HV silage improved with addition of both LAB and chlorella.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.1-7
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• 2017

Cobalt silicide was used as a counter electrode in order to confirm its reliability in dye-sensitized solar cell (DSSC) devices. 100 nm-Co/300 nm-Si/quartz was formed by an evaporator and cobalt silicide was formed by vacuum heat treatment at $700^{\circ}C$ for 60 min to form approximately 350 nm-CoSi. This process was followed by etching in $80^{\circ}C$-30% $H_2SO_4$ to remove the cobalt residue on the cobalt silicide surface. Also, for the comparison against Pt, we prepared a 100 nm-Pt/glass counter electrode. Cobalt silicide was used for the counter electrode in order to confirm its reliability in DSSC devices and maintained for 0, 168, 336, 504, 672, and 840 hours at $80^{\circ}C$. The photovoltaic properties of the DSSCs employing cobalt silicide were confirmed by using a simulator and potentiostat. Cyclic-voltammetry, field emission scanning electron microscopy, focused ion beam scanning electron microscopy, and energy dispersive spectrometry analyses were used to confirm the catalytic activity, microstructure, and composition, respectively. The energy conversion efficiency (ECE) as a function of time and ECE of the DSSC with Pt and CoSi counter electrodes were maintained for 504 hours. However, after 672 hours, the ECEs decreased to a half of their initial values. The results of the catalytic activity analysis showed that the catalytic activities of the Pt and CoSi counter electrodes decreased to 64% and 57% of their initial values, respectively(after 840 hours). The microstructure analysis showed that the CoSi layer improved the durability in the electrolyte, but because the stress concentrates on the contact surface between the lower quartz substrate and the CoSi layer, cracks are formed locally and flaking occurs. Thus, deterioration occurs due to the residual stress built up during the silicidation of the CoSi counter electrode, so it is necessary to take measures against these residual stresses, in order to ensure the reliability of the electrode.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.8-9
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• 2011

On 4 September 2010 an earthquake of magnitude 7.1 on the Richter scale occurred on the Canterbury Plains in the South Island of New Zealand. The Canterbury Plains are an area of extensive groundwater and spring fed surface water systems. Since the September earthquake there have been several thousand aftershocks (Fig. 1), the largest being a 6.3 magnitude quake which occurred close to the centre of Christchurch on 22February 2011. This second quake caused extensive damage to the city of Christchurch including the deaths of 189 people. Both of these quakes had marked hydrological impacts. Water is a vital natural resource for Canterburywith groundwater being extracted for potable supply and both ground and surface water being used extensively for agricultural and horticultural irrigation.The groundwater is of very high quality so that the city of Christchurch (population approx. 400,000) supplies untreated artesian water to the majority of households and businesses. Both earthquakes caused immediate hydrological effects, the most dramatic of which was the liquefaction of sediments and the release of shallow groundwater containing a fine grey silt-sand material. The liquefaction that occurred fitted within the empirical relationship between distance from epicentre and magnitude of quake described by Montgomery et al. (2003). . It appears that liquefaction resulted in development of discontinuities in confining layers. In some cases these appear to have been maintained by artesian pressure and continuing flow, and the springs are continuing to flow even now. In spring-fed streams there was an increase in flow that lasted for several days and in some cases flows remained high for several months afterwards although this could be linked to a very wet winter prior to the September earthquake. Analysis of the slope of baseflow recession for a spring-fed stream before and after the September earthquake shows no change, indicating no substantial change in the aquifer structure that feeds this stream.A complicating factor for consideration of river flows was that in some places the liquefaction of shallow sediments led to lateral spreading of river banks. The lateral spread lessened the channel cross section so water levels rose although the flow might not have risen accordingly. Groundwater level peaks moved both up and down, depending on the location of wells. Groundwater level changes for the two earthquakes were strongly related to the proximity to the epicentre. The February 2011 earthquake resulted in significantly larger groundwater level changes in eastern Christchurch than occurred in September 2010. In a well of similar distance from both epicentres the two events resulted in a similar sized increase in water level but the slightly slower rate of increase and the markedly slower recession recorded in the February event suggests that the well may have been partially blocked by sediment flowing into the well at depth. The effects of the February earthquake were more localised and in the area to the west of Christchurch it was the earlier earthquake that had greater impact. Many of the recorded responses have been compromised, or complicated, by damage or clogging and further inspections will need to be carried out to allow a more definitive interpretation. Nevertheless, it is reasonable to provisionally conclude that there is no clear evidence of significant change in aquifer pressures or properties. The different response of groundwater to earthquakes across the Canterbury Plains is the subject of a new research project about to start that uses the information to improve groundwater characterisation for the region. Montgomery D.R., Greenberg H.M., Smith D.T. (2003) Stream flow response to the Nisqually earthquake. Earth & Planetary Science Letters 209 19-28.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.328-332
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• 2009

A new malting barley variety, "Oreum", was developed from the a cross between 'Kinuyutaka' and 'Samdobori' at the Honam Agricultural Research Institute (HARI) in 2006. An elite line, YMB2077-2B-24-1-2, was selected in 2003 and designated as 'Milyang132'. It showed good agronomic performance in the regional adaptation yield trials (RYT) from 2004 to 2006, and was released with the name of "Oreum" having high yielding and BaYMV resistance. The average heading and maturing dates of "Oreum" were April 18 and May 24, which were 2 days later than 'Jinyang', a leading variety, at RYT. "Oreum" had longer culm length (75 cm), more spikes per $m^2$ (990), and lighter 1,000 grain weight (35.2 g) than those of 'Jinyang' in paddy field conditions. It was showed resistance to BaYMV at the regions of Naju, Jinju and Milyang but moderate resistance at Iksan. However, the response to other environmental stresses of was similar to 'Jinyang' The yield potential of "Oreum" was about 5.43 MT/ha, 4.93 MT/ha in upland and paddy fields which was about 80%, 35% higher than Jinyang in the regional adaptation yield trials (RYT), respectively. It has good malting quality including high grain assortment, germination capacity ratio, water sensitivity and high the malt production and the extract and short filtration speed than those of 'Jinyang'.