• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.465-474
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• 1996

The study was carried out to determine the proper concentration of plant growth regulator, kinetin on alleviating copper toxicity for two rice cultivars of seed germination. The results were as followings : Soaking treatment of kinetin 10$^{-3}$ M increased the germination rate of both cultivars, Ilpumbyeo and Hyangmibyeo 1 by 92% and 88% as compared with copper treatment (60ppm). But the soaking treatment effect of plant growth regulator, kinetin was not recognized at the kinetin 10$^{-4}$ M and 10$^{-5}$ M. Chlorophyll content of both rices was higher than that of Hyangmibyeo 1. Copper content of Ilpumbyeo was higher in leaf than in seed part. At the 3 days after treatment of copper 60ppm, both cultivars of treatment of kinetin 1O-3M showed the somewhat thin bands at the 35 and 40kDa compared with others. A new protein band pattern was only appeared to kinetin 1O-3M at approximately 54.4kDa(M. W) at the 7 days after treatment of copper 60ppm in llpumbyeo cultivar, SOD activity of copper 60ppm treatment increased in 3DAT, but there were no significant differences in 5 and 7DAT of two cultivars. Free proline contents of copper 60ppm treatment in llpumbyeo were remarkably increased about 4.996$\mu$M. In particular, free proline content of kinetin l0$^{-3}$ M in Ilpumbyeo was 5.008$\mu$M in 3DAT. In case of Hwangmibyeo 1, free proline content of copper 60ppm was 5.825$\mu$M compared with an untreated control showing 2.34l$\mu$M. The effects of kinetin treatment were recognized to promote the root growth and germination rate under copper toxicity(60ppm) condition in both cultivars.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.301-309
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• 1996

Since it has been reported that the depolarization-induced NE release is inhibited by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus, a large body of experimental data on the post-receptor mechanism of this process has been accumulated. But, the post-receptor mechanism of presynaptic $A_1-adenosine$ receptor on the NE release has not been clearly elucidated yet. Therefore, it was attempted to clarify the participation of $K^+-channel$ in the post-receptor mechanisms of the $A_1-adenosine$ receptor-mediated control of NE release in this study. Slices from rat hippocampus were equilibrated with $^3H-norepinephrine$ and the release of the labelled products was evoked by electrical stimulation (3 Hz, 5 $VCm^{-1}$, 2 ms, rectangular pulses), and the influence of various agents on the evoked tritium-outflow was investigated. Adenosine, in concentrations ranging from $1{\sim}30\;{\mu}M$, decreased the NE release in a dose-dependent manner, without affecting the basal rate of release. 4AP $(1{\sim}30{\mu}M)$, a specific A-type $K^+-channel$ blocker, increased the evoked NE release in a dose-related fashion, and the basal rate of release is increased by 10 and $30{\mu}M$. TEA $(1{\sim}10{\mu}\;M)$, a nonspecific $K^+-channel$ blocker, increased the evoked NE release in a dose-dependent manner without affecting basal release. The adenosine effects were significantly inhibites by 3 ${\mu}M$ 4AP and 10 mM TEA treatment. 4AP $(30{\mu}M)-$ and TEA (10 mM)-induced increments of evoked NE release were completely abolished in $Ca^{++} free, but these were recoverd in low $Ca^{++} medium. And the effects of $K^+-channel$ blockers in low $Ca^{++} medium were inhibites and abolishes by $Mg^{++} (4 mM) adding and TTX $(0.3{\mu}M)$ adding medium, respectively. These results suggest that the decrement of the evoked NE-release by $A_1-adenosine$ receptor is mediated by 4AP and TEA sensitive $K^+-channel$.

• Korean journal of applied entomology
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• v.45 no.1 s.142
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• pp.59-66
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• 2006

The damaged area by and the distribution of Japanese gall forming thrips, Ponticulothrips diospyrosi Haga et Okajima (Thysanoptera: Phlaeothripidae) in Korea were surveyed based on the answers of persimmon growers to questionnaire. Seasonal occurrence of each developmental stage was estimated by monitoring the individuals in damaged leaves, and effect of trap site and side of sticky board were studied by yellow sticky traps at three sweet persimmon orchards in Gimhae and Jinju (orchards A and B), Gyeongnam province, Korea in 2005. P. diospyrosi gave damage to astringent persimmon as well as sweet one. The damaged area of persimmon orchard has sharply increased since 2000, reaching 446 ha nationwide; Gyeongnam province was most severely damaged, followed by Gyeongbuk and Jeonnam provinces. Most of the farmers answered that they sprayed insecticides and removed the damaged leaves to control P. diospyrosi. The overwintered adults were observed in the damaged-rolled leaves from mid May and the 1st generation adults from early-mid June. No thrips were observed in the damaged leaves after mid July. Yellow sticky trap data showed that peak adults catch of the overwintered generation was mid May, and that of the 1st generation was mid-late June in Gimhae and late June in Jinju. Sticky traps set at orchard-pine forest border caught significantly more number of the 1st generation adults than those at the orchard center, even though timing of peak catches was not different between the two sites. There was a tendency of more catches on the side of sticky trap facing pine forest than the other side facing orchard center, even though the catches on both sides showed no statistical difference.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.785-795
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• 2018

The International Maritime Organization (IMO) has recognized the risk of hull fouling and announced '2011 Guidelines for the control and management of ship's biofouling to minimize the transfer of invasive aquatic species'and is planning international regulations to enforce them in the future. In this study, to effectively respond to future international regulation, we introduce the case of leading countries related to management of hull fouling and also investigate environmental risk assessment techniques for in-water cleaning. Australia and New Zealand, the leading countries in hull fouling management, have established hull fouling regulations through biological and chemical risk assessment based on in-water cleaning scenarios. Most European countries without their government regulation have been found to perform in-water cleaning in accordance with the IMO's hull fouling regulations. In the Republic of Korea, there is no domestic law for hull fouling organisms, and only approximately 17 species of marine ecological disturbance organisms, are designated and managed under the Marine Ecosystem Law. Since in-water cleaning is accompanied by diffusion of alien species and release of chemical substances into aquatic environments, results from biological as well as chemical risk assessment are performed separately, and then evaluation of in-water cleaning permission is judged by combining these two results. Biological risk assessment created 40 codes of in-water cleaning scenarios, and calculated Risk Priority Number (RPN) scores based on key factors that affect intrusion of alien species during in-water cleaning. Chemical risk assessment was performed using the MAMPEC (Marine Antifoulant Model to Predict Environmental Concentrations), to determine PEC and PNEC values based on copper concentration released during in-water cleaning. Finally, if the PEC/PNEC ratio is >1, it means that chemical risk is high. Based on the assumption that the R/V EARDO ship performs in-water cleaning at Busan's Gamcheon Port, biological risk was estimated to be low due to the RPN value was <10,000, but the PEC/PNEC ratio was higher than 1, it was evaluated as impossible for in-water cleaning. Therefore, it will be necessary for the Republic of Korea to develop the in-water cleaning technology by referring to the case of leading countries and to establish domestic law of ship's hull fouling management, suitable for domestic harbors.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.249-256
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• 1983

The aspect of flowering was investigated in 'Georgia' cut lilies which had four flowers per stem. Concurrently effects of preservative solutions on longevity, petal length, water uptake and fresh weight of cut flowers were examined. 1. Days of opening of the 1st, 2nd and 3rd flower were 1-2 days, 3-4 days and 5-6days after beginning of holding treatment respectively. But the 4th flower was opened 9-10 days after beginning of holding treatment when the 1st and 2nd flowers were wilting or drying. 2. The later the opening of flower in a stem was, the shorter the longevity of flower became. But the effects of preservative solutions on longevity were gradually increased as the opening of flower was late in a stem. 3. Preservative solutions containing sucrose and $AgNO_3$ or HQ were able to increase petal length and longevity of the 3rd and 4th flowers sufficiently like the 1st and 2nd flowers. 4. Petal length, water uptake, fresh weight and longevity of cut lilies held in preservative solution containing sucrose, $AgNO_3$ and HQ were increased significantly compared with others. Solution containing sucrose alone increased longevity but decreased water uptake remarkably and did not increase fresh weight and petal length effectively compared with the control.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.448-453
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• 2014

Influences of shading and irrigation in summer hot pepper cultivation on the plant growth and mesophyll tissue were investigated. Hot pepper plants were exposed to three shade levels (0, $30{\pm}5$ and $80{\pm}5%$) and irrigated or non-irrigated in greenhouse condition. Plant height and leaf area were highest in 30% shading and stem diameter and fresh and dry weights were highest in no shading. Plant growth was better in rain shelters with irrigation than in those without irrigation. The numbers of hot pepper fruits in the beginning of harvest were 49 in rain shelters without irrigation and shading, 22 in those with irrigation and without shading, 5 in those without irrigation with 30% shading, and 1 in those with irrigation and 30% shading. However, 80% shading showed lowest flower number and flower abscission, resulting in no fruit set, regardless of irritation. This is because carbohydrate translocation from leaves to reproductive organs may be not enough for developing fruits due to the lack of sunlight. The yield of hot pepper tended to be higher in rain shelter with irrigation than in those without irrigation. In optical microscopy observation, the thickness and development of mesophyll tissues decreased as increasing the degree of shading but no effect of irrigation on mesophyll tissues was observed. When stomata were observed with scanning electron microscope (SEM), the shape of stomata was normal but tissues surrounding stomata were slightly wrinkled in plants grown under 30% shading. The large number of abnormal stomata and wrinkled leaves was observed among plants grown in rain shelters with 80% shading. In plants grown in rain shelters without irrigation, tissues surrounding stomata were wrinkled and 10-20% decrease in the number of stomata was observed. Therefore, in hot pepper cultivation in summer with high temperature, shading was not effective for fruit yield and mesophyll tissue development; if shading is unavoidable, high degree of shading is not advisable. Further studies are needed for appropriate cultivar selection and environment-control techniques in hot pepper cultivation in summer with high temperature.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.3
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• pp.249-254
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• 1992

This research was conducted to investigate the effects of fly ash applications on growth and yield parameters of corn (Zea mays L.), and soil chemical properties. Corn height at silking stage, and height and dry matter ratio at harvesting stage were enhanced by applications of fly ashes derived from bituminous coal and anthracite, respectively. Effects of fly ash treatment on growth parameters of corn were varied with kinds and levels of fly ash application and growth periods, but relatively small without revealing a major negative effect as compared to the control. Yield of corn was increased by applying fly ash of anthracite origin, but other yield components were not influenced negatively by fly ash treatment. Soil total carbon contents, cation exchange capacity, and phosphorus contents of soils sampled after harvest of corn were significantly increased by fly ash treatment, although there were slightly different effects according to kinds and levels of fly ash application. Exchangeable cations of soils were varied within an experimental error range. Phosphorus taken up by corn was enhanced by treating fly ash of the bituminous coal to the soil and there were a positive correlation between phosphorus uptake and soil Phosphorus level. Cation uptake by corn was changed a little, but no significant reduction was observed in cation uptake due to fly ash treatment. It seems to be difficult to figure out the mechanism of fly ash effects on growth and nutrient uptake by corn with one year field experiment, however treatment of fly ash enhanced some parameters of growth and yield, and nutrient uptake by corn without revealing any major negative effects. To determine the value of fly ash as a fertilizer source, continuous researches under various soil and crop conditions were considered to be necessary.

• Journal of Yeungnam Medical Science
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• v.15 no.1
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• pp.97-113
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• 1998

The sympathoadrenal system plays an important role in homeostasis in widely varing external environments. Conflicting findings, however, have been reported on its response to hypoxia. We investigated the effect of hypoxia on the sympathoadrenal system in dogs under halothane anesthesia by measuring levels of circulating catecholamines in response to graded hypoxia. Ten healthy mongreal dogs were mechanically ventilated with different hypoxic gas mixtures. Graded hypoxia and reoxygenation were induced by progressively decreasing the oxygen fraction in the inhalation gas mixture from 21%(control) to 15%, 10% and 5% at every 5 minutes, and then reoxygenated with 60% oxygen. Mean arterial pressure, central venous pressure and mean pulmonary arterial pressure were measured directly using pressure transducers. Cardiac output was measured by the thermodilutional method. For analysis of blood gas, saturation and content, arterial and mixed venous blood were sampled via the femoral and pulmonary artery at the end of each hypoxic condition. The concentration of plasma catecholamines was determined by radioenzymatic assay. According to the exposure of graded hypoxia, not only did arterial and mixed venous oxygen tension decreased markedly at 10% and 5% oxygen, but also arterial and mixed venous oxygen saturation decreased significantly. An increased trend of the oxygen extraction ratio was seen during graded hypoxia. Cardiac output, mean arterial pressure and systemic vascular resistance were unchanged or increased slightly. Pulmonary arterial pressure(PAP) and pulmonary vascular resistance(PVR) were increased by 55%, 76% in 10% oxygen and by 82%, 95% in 5% oxygen, respectively(p<0.01). The concentrations of plasma norepinephrine, epinephrine and dopamine increased by 75%, 29%, 24% in 15% oxygen and by 382%, 350%, 49% in 5% oxygen. These data suggest that the sympathetic nervous system was activated to maintain homeostasis by modifying blood flow distribution to improve oxygen delivery to tissues by hypoxia, but hemodynamic changes might be blunted by high concentration of nitrous oxide except PAP and PVR. It would be suggested that hemodynamic changes might not be sensitive index during hypoxia induced by high concentration of nitrous oxide exposure.

• Journal of the Korean Applied Science and Technology
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• v.31 no.2
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• pp.255-264
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• 2014

This study was performed to elucidate the biochemical mechanism of metabolism on reducing blood lipid, by oral administration of egg yolk in rats. A total of 36 Sprague Dawley male rats were randomized into four treatment groups, according to a randomized block design. Each group was further divided into three repeat cages, with each repeat cage comprising of 3 rats. The animals were orally administered with egg yolk once a day, while feeding the same purified pellet diet for 6 weeks. The four treatment groups were: C(control, saline 1.0 g), T1(pork belly oil 1.0 g), T2(egg yolk 1.0 g), T3(pork belly oil 1.0 g and egg yolk 1.0 g alternating every week). The measured parameters in each group are listed as follows in the order of highest to the lowest: daily average gain of body weight(T1>T3>T2>C); blood triglyceride and total cholesterol(T1>C>T3>T2) HDL-C (T2>C>T3>T1); and LDL-C (T1>T3>C>T2). AST and ALT, which are the index of liver function, were the highest in T1 but was lowest in T2. The weights of the liver, spleen, and kidney, except for the abdominal fat, showed no significant difference. The weight of abdominal fat was the highest in T1, but there were no significant difference among C, T2, and T3. The HMG-CoA reductase activity was the highest in T1 followed by T3, C but T2 was lowest. The daily fecal excretions of the total sterol, neutral sterol and acid sterol was highest in T2 but lowest in T1. The results of this study show that the egg consumption reduces the blood lipid through facilitation of fecal excretions of sterols and inhibition of enzyme activity in cholesterol biosynthesis, in the liver of animal and human.

• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1378-1384
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• 2005

Purpose : We hypothesized dexrazoxane(DXR) and pentoxifylline(PTX) may prevent myocardial damage in adriamycin(ADR)-induced cardiomyopathic rat model. We also investigated their effects on the myocardial apoptosis and fibrosis in ADR induced cardiomyopathy. Methods : The six-week old female Spregue-Dawley rats were divided into control group(CNT, n=4), ADR group(n=6), ADR+DXR group(DXR, n=5), ADR+PTX group(PTX, n=6), ADR+DXR+PTX group(DXPT, n=5). ADR(5 mg/week, twice) was administrated intravenously to rats except CNT group to induce cardiomyopathy. The PTX(50 mg/kg/day) was administered daily from day-0 to Day-21. The DXR(100 mg/kg) was administered 30 minutes before each ADR injection. On day 21, the rats were sacrificed and the degree of histopathologic changes of hypercontraction band necrosis, cytoplasmic vacuolar change and fibrosis were scored. Immunohistochemical staining for Bcl-2 expression and RT-PCR for $TNF-{\alpha}$ and CTGF were performed. Results : Histopathological scores of myocardial damage were significantly higher in ADR rats than CNT rats(P<0.05), and significantly lower in DXPT rats than ADR rats(P<0.01). Myocardial fibrosis was prevented in both PTX rats and DXPT rats. The expression of Bcl-2 was weaker in ADR rats than that in CNT rats(P<0.05), and stronger in both DXR and DXPT rats than that in ADR rats (P<0.05). $TNF-{\alpha}$ concentration of ADR rats was not different from that of treated groups. Conclusion : DXR prevented myocyte apoptosis with increased Bcl-2 expression, and PTX prevented myocardial fibrosis in ADR induced cardiomyopathic rats. The combination therapy of DXR and PTX showed prevention of cardiomyopathy in ADR induced cardiomyopathy rat model.