• The Korean Journal of Pharmacology
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• v.19 no.1
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• pp.15-35
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• 1983

Although it has been well known that ventricular fibrillation is the most important complication during hypothermia, much investigation has failed to show the exact nature of the etiology of ventricular fibrillation. Recently, there has been considerable research on the relationship between sympathetic activity and ventricular fibrillation under hypothermia. Cardiac muscle normally contains a certain amount of norepinephrine and the dramatic effect of this catecholamines on the cardiac muscle is well documented. It is, therefore, conceivable that cardiac catecholamines might exert an influence on the susceptibility of heart muscle to tachycardia, ventricular fibrillation and arrhythmia, under hypothermia. Hypothermia itself is stress enough to increase tonus of sympatheticoadrenal system. The normal heart is supplied by an autonomic innervation and is subjected to action of circulating catecholamines which may be released from the heart. If the reaction of the heart associated with a variable amount of cardiac catecholamines is. permitted to occur in the induction of hypothermia, the action of this agent on the heart has not to be differentiated from the direct effects of cooling. The studies presented in this paper were designed to provide further information about the cardio-physiological effects of reduced body temperature, with special reference to the role of catecholamines in ventricular fibrillation. Healthy cats, weighing about 3 kg, were anesthetized with pentobarbital(30 mg/kg) intraperitoneally. The trachea was intubated and the endotracheal tube was connected to a C.F. Palmer type A.C. respirator. Hypothermia was induced by immersing the cat into a ice water tub and the rate of body temperature lowering was $1^{\circ}C$ per 5 to 8 min. Esophageal temperature and ECG (Lead II) were simultaneously monitored. In some cases the blood pH and serum sodium and potassium were estimated before the experiment. After the experiment the animals were killed and the hearts were excised. The catecholamines content of the cardiac muscle was measured by the method of Shore and Olin (1958). The results obtained are summarized as follows. 1) In control animal the heart rate was slowed as the temperature fell and the average pulse rates of eight animals were read 94/min at $31^{\circ}C$, 70/min at $27^{\circ}C$ and 43/min at $23^{\circ}C$ if esophageal temperature. Ventricular fibrillation was occurred with no exception at a mean temperature of $20.3^{\circ}C(21-l9^{\circ}C)$. The electrocardiogram revealed abnormal P waves in each progressive cooling of the heart. there was, ultimately, a marked delay in the P-R interval, QRS complex and Q-T interval. Inversion of the T waves was characteristic of all animals. The catecholamines content of the heart muscle excised immediately after the occurrence of ventricular fibrillation was about thirty percent lower than that of the pre-hypothermic heart, that is, $1.0\;{\mu}g/g$ wet weight compared to the prehypothermic value of $1.41\;{\mu}g/g$ wet weight. The changes of blood pH, serum sodium and potassium concentration were not remarkable. 2) By the adrenergic receptor blocking agent, DCI(2-3 mg/kg), given intramuscularly thirty minutes before hypothermia, ventricular fibrillation did not occur in one of five animals when their body temperature was reduced even to $16^{\circ}C$. These animals succumbed at that low temperature, and the changes of heart rate and loss of myocardial catecholamines after hypothermia were similar to those of normal animals. The actual effect of DCI preventing the ventricular fibrillation is not predictable. 3) Administration of reserpine(1 mg/kg, i.m.) 24 hours Prior to hypothermia disclosed reduced incidence of ventricular fibrillation, that is, six of the nine animals went into fibrillation at an average temperature of $19.6^{\circ}C$. By reserpine myocardial catecholamines content dropped to $0.045\;{\mu}g/g$ wet weight. 4) Bretylium pretreatment(20 mg/kg, i.m.), which blocks the release of catecholamines, Prevented the ventricular fibrillation under hypothermia in four of the eight cats. The pulse rate, however, was approximately the same as control and in some cases was rather slower. 5) Six cats treated with norepinephrine(2 mg/kg, i.m.) or DOPA(50 mg/kg) and tranylcypromine(10 mg/kg), which tab teen proved to cause significant increase in the catecholamines content of the heart muscle, showed ventricular fibrillation in all animals under hypothermia at average temperature of $21.6^{\circ}C$ and the pulse rate increased remarkably as compared with that of normal. Catecholamines content of cardiac muscle of these animals markedly decreased after hypothermia but higher than control animals. 6) The functional refractory periods of isolated rabbit atria, determined by the paired stimulus technique, was markedly shortened by administration of epinephrine, norepinephrine and isoproterenol. 7) Adrenergic beta-blocking agents, such as pronethalol, propranolol and sotalol(MJ-1999), inhibited completely the shortening of refractory period induced by norepinephrine. 8) Pretreatment with either phenoxftenbamine or phentolamine, an adrenergic alphatlocking agent, did not modify the decrease in refractory period induced by norepinephrine. From the above experiment it is possible to conclude that catecholamines play an important role in producing ventricular fibrillation under hypothermia. The shortening of the refractorf period of cardiac muscle induced by catecholamines mar be considered as a partial factor in producing ventriculr fibrillaton and to be mediated by beta-adrenergic receptor.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.216-224
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• 1998

The objective of this study was to investigate the effect of sesame monoculture and sesame in rotation (SR) with maize. soybean. barley or rye on reduction of injury by continous cropping in sesame. Field studies were conducted for 3-years (1995~1997) at the experimental field of the Crop Experiment Station. Compared to CS (continuous sesame). SR treatments turned out to keep more organic matter and higher exchangeable cation concentrations in soils. BS (barley and sesame in a 1-year rotation) and RS (rye and sesame in a 1-yea r rotation) treatments had significantly greater available $P_2O_5$ contents in soils than CS, MS (maize and sesame in a 3-year rotation) and SbS (soybean a nd sesame in a 3-year rotation). The pH of the soils under different treatments were not significantly different. SR treatments exhibited significantly lower bulk density and higher pore space than CS. Soil microbial biomass C (SMBC) and N (SMBN) were determined by the chloroform fumigation-extraction method. SMBC and SMBN were significantly higher in soils under BS and RS than those under CS, but only during the 1 year of monitoring. MS and SbS treatments resulted in higher SMBC and SMBN than CS. The occurrence of injury by disease of sesame is the important primary factor of injury by continous cropping, but the disease occurrence with rotation did not decrease in th is experiment. Under CS treatment, the growth and grain of sesame was significantly lower than those under other treatments. Compared to CS, the increments of grain yield of sesame were 68, 63, 57 and 51% for MS, RS, SbS and BS, respectively in the first harvest. In the second harvest, they were 24% for MS, 28% for RS, 20% for SbS and 19% for BS. The average increase ratios during the two years were 41, 41, 34, and 33% for MS, RS, SbS and BS, respectively.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.841-849
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• 1996

Quality changes in carrot during storage were studied to investigate the efficiency, cooling properties and the washing and storage effects of hydrocooling method. As a result of plotting the nondimensionalized carrot temperature versus cooling time, its cooling rate coefficient was shown $-0.0171min^{-1}{\sim}-0.0121min^{-1}\;(R^{2}=0.99{\sim}0.95)$, and $-0.141min^{-1}{\sim}-0.0038min^{-1}\;(R^{2}=0.98{\sim}0.92)$ in package condition7. Rate of weight loss and change in moisture content of carrot were not significantly different by treatment conditions during storage at $5^{\circ}C$. During storage at $15^{\circ}C$, however, weight loss of hydrocooled carrot was lower than that of non-treated carrot from the 30th to 40th day. Especially, PE was more effective than tray for packaging hydrocooled carrots. Carrot pretreated wish sterilizing agent, packed with PE vinyl film and with residual water removed after hydrocooling showed a lower decaying-rate than any other carrots. Changes in Hunter L and b values of hydrocooled carrot were slower than those of non-treated one. The carotenoids contents of stored carrot $(0.736{\sim}0.780mg%)$ decreased to $9{\sim}43%$ after 40 days of storage at $5^{\circ}C$ and before 20 days of storage at $15^{\circ}C$. It could be presumed that the addition of sterilizing agent reduced the initial level of overall microbial and coliform counts and their growth rate during storage.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.357-370
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• 1982

Recent concern regarding price and availability of fossil fuels has spurred the interest in alternative sources for farm crop drying. Among the available options such as biomass energy, wind power, nuclear energy and solar energy etc., the increasing attention is being directed to the utilization of heat from solar energy especially for farm crop drying. Even though solar energy is dispersed over a large land area and only a relatively small amount of energy can be simply collected, the advantages of solar energy is that the energy is free, non-polluting. The study reported here was designed to help supply the informations for the development of simple and relatively inexpensive solar warehouse for farm crop drying and storage. Specifically, the objectives of this study were to determine the performance of the solar collector fabricated, to compare solar supplemented heat drying with natural air drying and to develop a simulation model of temperature in stored grain, which can be used to study the effects due to changes in ambient air temperature. For those above objectives, solar collector was fabricated from available materials. Corrugated steel galvanized sheet, painted flat black, was used as absorbers and clear 0.2mm polyethylene sheet was the cover material. The warehouse for rough rice drying and storage was constructed with concrete block, and the solar collector was used as the roof of warehouse instead of original roofing system of it. The results obtained in this study were as follows: 1. The thermal efficiency of the solar collector was average 26 percent and the overall heat transfer coefficient of the collector was approximately $25kJ/hr.m^2\;^{\circ}K$. 2. Solar heated air was sufficient to dry one cubic meter of rough rice from 23.5 to 15.0 percent in 7 days and natural air was able to dry the same amount of rough rice from 20.0 to 5 percent in l2 days. 3. Drying with solar heat reduced the required drying time to dry the same amount of rough rice into a half compared to natural air drying, but overdrying problems of the bottom layer were so severe that these problems should be thoroughly analyzed. 4. Simulation model of temperature in stored grain was developed and the results of predicted temperature agreed well with test results. 5. Based on those simulated temperature, changes in the grain-temperature were a large at the points of the wallside and the damage of the grain would be severe at the contact area of wall.

• Journal of Mushroom
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• v.15 no.3
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• pp.129-133
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• 2017

Oyster mushroom is a type of mushroom that is commonly cultivated and consumed in Korea. P. ostreatus 'Suhan' is a preferred cultivar for many mushroom farmers because it has a dark pileus and thick stipe. However, as it is very sensitive to environmental conditions, farmers consistently demand an alternative cultivar. To develop a new cultivar, the parental strains KMCC01680 ('Suhan') and KMCC00478 ('Gosol') were selected from various collected P. ostreatus strains by cultivating genetic resources. P. ostreatus 'Heuksol' was developed by the method of Mon-Mon crossing between monokaryotic strains derived from 'Suhan' and 'Gosol'. Thirty strains of 174 crossed strains were initially selected by cultivation experiments. After bulk cultivation tests, 'Heuksol' was selected. The nuclear DNA profile of 'Heuksol' was similar to those of the parental strains, 'Suhan' and 'Gosol', when RAPD (random amplified polymorphic DNA) primers and UPF (Universal PCR Fingerprinting) 2, 3, and 4 were used. The optimum temperature for mycelial growth was $30^{\circ}C$ for 'Heuksol', but medium-high temperatures were also appropriate, especially $13-20^{\circ}C$. The fruiting body production per bottle (1,100 mL) was approximately 140.8 g. When compared to the control strain 'Suhan', the thickness of the stipe of 'Heuksol' was greater than that of 'Suhan' (13.5 mm vs 9.4 mm). The pileus diameter of 'Heuksol' was similar to that of 'Suhan' and the pileus thickness of 'Heuksol' and 'Suhan' was 19.7 mm and 21.8 mm, respectively. 'Heuksol' had more a productive stipe number than 'Suhan' and the pileus of 'Heuksol' was dark gray, even at high temperatures. Therefore, it was suggested that this new cultivar, 'Heuksol', could provide an alternative to 'Suhan' and contribute to the profit of oyster mushroom farms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.496-502
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• 2005

The chemical properties and nitrite scavenging ability were analyzed which on a citron (Citrus junos) of 4 kinds purchased in different regions [Namhae (I, II), Tongyoung and Koheung] in Korea. Four kinds of organic acids were determined. Citric acid contents in flesh and peel of citron were $10.2\pm0.14\~17.7\pm0.17\;g/100g$. The organic acid content was the highest in citron purchased from Koheung. Total mineral content in citron was in a range of $2,844.3\~4,022.4$ mg/100 g, the potassium content was the highest in the range of $1,332.4\pm2.31\~2,308.5{\pm}3.25\;mg/l00g$. The major free amino acid from citron were proline, asparagine and glutamic acid. And the highest in peel of citron purchased from Tongyoung by 326.9 mg/100 g. However, the kinds and contents of chemical components in citron were somewhat different among various regions. The electron donating ability using DPPH method of citron juice was more than $80.0\%$ at the concentration of $0.1\~0.2\%$ and it was stronger by increased the juice concentration in the reaction mixture. SOD-like activity showed $10.2\pm0.50\~20.1\pm0.77\%$ at the concentration of $0.01\~0.2\%$. The nitrite scavenging ability was pH and sample concentration dependent. It was the highest at the pH 1.2 and more than $73\%$ in $0.1\~0.2\%$ citron juice. On the contrary in all concentration of added citron juice lower than $27\%$ at pH 4.2.

• Childhood Kidney Diseases
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• v.11 no.2
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• pp.203-211
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• 2007

Purpose : We attempted to compare the independent factors such as age, sex, C-reactive protein(CRP), and white blood cell count(WBC) in children with radiologic studies and assess the necessity of performing voiding cystourethrography(VCUG). Method : 98 children who have been diagnosed their first time febrile urinary tract infection from Janurary 2002 to Januray 2005 were enrolled. In all patient, the duration of fever which occurred before and after treatment was recorded, and CRP, WBC, $^{99m}Tc$-2,3-dimercaptosuccinic acid($^{99m}Tc$-DMSA) renal scans, renal ultrasound and VCUG were analyzed. Results : Of the 98 children diagnosed with urinary tract infection(UTI), 52 were male and 46 were female. 18 had abnormalities in VCUG, 17 had abnormalities in kidney ultrasound, and 20 had partial defects or diffuse uptake decrease in $^{99m}Tc$-DMSA renal scans. There were no significant relationship between incidence of radiologic abnormalities and age. The risk of renal scar was significantly higher in children who had a longer febrile period before treatment than in those with shorter period. Both CRP and WBC were significantly elevated in children with the radiological abnormalities. A positive of $^{99m}Tc$-DMSA renal scans and renal ultrasound were highly associated with vesicoureteral reflux(VUR). Conclusion : If there are abnormalities in the kidney ultrasound and $^{99m}Tc$-DMSA renal scan of a child with initial UTI, a VCUG is recommended. Even in cases without abnormal findings in $^{99m}Tc$-DMSA renal scan and renal ultrasound, clinical data such as CRP and WBC should be assessed, and VCUG should be Performed for the undetected VUR.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.8-15
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• 2007

Conjugated linoleic acid (CLA) was chemically synthesized using the alkaline isomerization method of com oil. CLA-TG was synthesized by reaction with sodium methoxide. Five different treatments were devised based on differences in the amount of CLA-TG added into the pressed han. for controls, 10% of pork back fat among the total component was only added without any CLA-TG. For the first treatment, 5% of CLA-TG among the lard component added into the press ham was replaced. For the 2nd, 3rd and 4th treatments, 10%, 15% and 20% of CLA-TG was respectively replaced. Pressed ham manufactured using CLA-TG was vacuum packaged and then stored for 1, 7, 14, 21 and 28 days at $4^{\circ}C$. Samples were analyzed for chemical composition, physico-chemical properties (pH, color), and texture characteristics. Typical chemical composition characteristics (moisture, crude protein, crude fat) were not significantly different between controls and CLA-TG treatment groups. Crude fat content of CLA-TG treatment groups was significantly lower than that of controls (p<0.05). pH values of controls was higher than that of CLA-TG treatment groups. The pH of control and CLA-TG treatment groups increased significantly as the storage period increased (p<0.05). Meat color (CIE $L^*,\;b^*$) of CLA-TG treatment groups was higher than that of controls. $a^*$ values were decreased by replacement of CLA-TG, but appeared to be unaffected by storage length. There was no significant difference in texture between controls and CLA-TG treatment groups. Based on these findings, we conclude that the physico-chemical properties and texture characteristics of manufactured pressed ham were not affected by CLA-TG addition. Also, our results indicate that high-quality pressed ham can be manufactured with CLA accumulation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.655-661
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• 1995

This study was conducted to get basic information of dry matter production and agronomic characteristics for increasing grain ripening in rice cultivar with large grains. Three cultivars which have different grain size were used. Of the two large grain cultivars, SR7796-3-1-5-1-l(SR7796F$_{7}$) had long culm and SR11269-13-3-4-2(SR11269F$_{6}$) had short culm. On the other hand, Tamjinbyeo was recommended cultivar had medium size of grain and culm. LAI was highest in Tamjinbyeo, followed by the SR11269F$_{6}$ and SR7796F$_{7}$, LAI decrement was higher in large grain cultivars than that of Tamjinbyeo after 20days after heading. Total dry weight(TDW) of areal part was highest in SR11269F$_{6}$, followed by the Tamjinbyeo and SR7796F$_{7}$. Dry weight (DW) of stem (leaf sheath+culm) at harvesting stage was decreased 15%, 12% in Tamjinbyeo, SR11269F$_{6}$, respectively, but was increased 5% in SR7796F$_{7}$ compared to heading stage. In distribution rate of each organ to TDW, distribution rate of leaf blade was low in large grain cultivar, but that of stem in Tamjinbyeo, SR7796F$_{7}$ and SR11269F$_{6}$ was 36%, 38% and 42%, respectively. In canopy architecture leaf blade weight was the highest 30~40cm, 40~50cm and 70~8Ocm above the ground in SR11269F$_{6}$, Tamjinbyeo and SR7796F$_{7}$, respectively. Range of panicle distribution in the canopy was 40cm in Tamjinbyeo, and was 70cm in large-grain cultivars. The results suggest that it has to take a growing interest in developing culture method for increasing LAI during growth stage, especially, around heading, in keeping green leaf till ripening stage and also in growing unformly plant within rice hill in large grain cultivars.cultivars.ltivars.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.2
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• pp.145-154
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• 2004

The objective of this experiment was to suggest the optimum cutting height for turf type mixtures{Kentucky bluegrass(Newport) 40％ + tall fescue(Rebell Jr) 20％ + perennial ryegrass (Palmer Ⅱ) 10% + redtop(Barricuda) 10％ + red fescue(Salem) 10% + creeping bentgrass(Crenshaw) IO%}. The fields trials were conducted from 1998 to 2001 at Chungnam National University in order to evaluate the dry matter yield and quality on the cutting heights(3, 4, and 5cm). With increasing the cutting height, the average DM yields of turf type mixtures over 3-year significantly increased, therefore the average total DM yields were obtained 11,158, 12,143 and 13,181㎏/ha at cutting height 3, 4 and 5cm(p<0.05), respectively. The CP content and OMO decreased(p<0.05), whereas the fiber contents slightly increased with increasing the cutting height. The average CPDM and DDM yields were obtained 2,012 and 8,621㎏, 2,097 and 9,461㎏, and 2,298 and 9,951㎏ at cutting height 3, 4, and 5㎝(p<0.05), respectively. The botanical compositions of Kentucky bluegrass and tall fescue were maintained high as 30 ∼ 36％, but that of perennial ryegrass was maintained low as 10-15%. Most of other species were low, but redtop and creeping bentgrass among the other species made up 8∼10％ and 7 ∼ 8% of botanical composition at the last 6th cutting time in 2001, respectively. In general, the level of cutting height of turf type mixtures was not more closely associated with botanical composition. The results of this experiment indicated that a 5㎝ of cutting height of turf type mixtures sown by extensive method would seemed adequate.