• The Korean Journal of Physiology
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• v.18 no.1
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• pp.19-35
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• 1984

Since the first report of Drury and $Szent-Gy{\ddot{o}}rgyi$ in 1929, the inhibitory influences of adenosine on the heart have repeatedly been described by many investigators. These studies have shown that adenosine and adenine nucleotides have overall depressant effects, similar to those of acetylcholine. Heart beats become slow and weak. It is also well known that adenosine is a potent endogenous coronary vasodilator. Many investigations on the working mechanisms of adenosine have been focused mainly on the effects of the coronary blood flow. However, the cellular mechanisms underlying the inhibitory action of adenosine on sinus node are not well understood yet. Thus, this study was undertaken to examine the behavior of rabbit SA node under influence of adenosine. In these series of experiments three kinds of preparations were used: whole atrial pair, left atrial strip, and isolated SA node preparations. The electrical activity of SA node was recorded with conventional glass microelectrodes 30 to 50 $M{\Omega}$. The preparations were superfused with bicarbonate-buffered Tyrode solution of pH 7.35 and aerated with a gas mixture of $3%\;CO_2-97%\;O_2$ at $35^{\circ}C$. In whole atrial pair, adenosine suppressed sinoatrial rhythm in a dose-dependent manner. Effect of adenosine on atrial rate appeared at the concentration of $10^{-5}M$ and was enhanced in parallel with the increase in adenosine concentration. Inhibitory action of adenosine on pacemaker activity was more prominent in the preparation pretreated with norepinephrine, which can steepen the slope of pacemaker potential by increasing permeability of $Ca^{+2}$. Calcium ions in perfusate slowly produced a marked change in sinoatrial rhythm. Elevation of the calcium concentration from 0.3 to 8 mM increased the atrial rate from 132 to 174 beats/min, but over 10 mM $Ca^{+2}$ decreased. The inhibitory effect of adenosine on sinoatrial rhythm developed very rapidly. Atrial rate was recovered promptly from the adenosine-induced suppression by the addition of norepinephrine, but extra $Ca^{+2}$ was less suitable to restore the suppression of atrial rate. Adenosine suppressed also atrial contractility in the same dosage range that restricted pacemaker activity, even in the reserpinized preparation. In isolated SA node preparation, spontaneous firing rate of SA node at $35^{\circ}C$(mean{\pm}SEM, n=16) was $154{\pm}3.3\;beats/min. The parameters of action potentials were: maximum diastolic potential(MDP), $-73{\pm}1.7\;mV: overshoot(OS), $9{\pm}1.4\;mV: slope of pacemaker potential(SPP), $94{\pm}3.0\;mV/sec. Adenosine suppressed the firing rate of SA node in a dose-dependent manner. This inhibitory effect appeared at the concentration of $10^{-6}M$ and was in parallel with the increase in adenosine concentration. Changes in action potential by adenosine were dose-dependent increase of MDP and decrease of SPP until $10^{-4}M$. Above this concentration, however, the amplitude of action potential decreased markedly due to the simultaneous decrease of both MDP and OS. All these effects of adenosine were not affected by pretreatment of atropine and propranolol. Lowering extra $Ca^{2+}$ irom 2 mM to 0.3 mM resulted in a marked decrease of OS and SPP, but almost no change of MDP. However, increase of perfusate $Ca^{2+}$ from 2 mM to 6 or 8 mM produced a prominent decrease of MDP and a slight increase of OS and SPP. Dipyridamole(DPM), which is known to block the adenosine transport across the cell membrane, definately potentiated the action of adenosine. The results of this experiment suggest that adenosine suppressed pacemaker activity and atrial contractility simultaneously and directly, by decreasing $Ca^{2+}-permeability$ of nodal and atrial cell membranes.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.1
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• pp.98-107
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• 2015

Olive flounder contains rich amount of lysine which is required for children's growth. Moreover, it is good foodstuffs for elderly, convalescent and diabetics because of low lipid content and high digestibility. This study was investigated for the purpose of obtaining basic data which can be applied to the processing of olive flounder steak. Olive flounder 100 g were chopped, mixed with vegetable (onion 20%, celery 10%, carrot 15%, garlic 1% of chopped olive flounder meat) and ingredient (bread crumbs 20 g, onion 15 g, celery 10 g, egg 1 ea, tarragon 1/2 t, blanc sauce 20 g, fresh cream 20 mL, salt and pepper pinch). Mixed dough was molded into steak shape ($12{\times}7cm$) and was processed by two types of products, Steak-1 {Roasting for 2 minutes in a frying pan wrapped with olive oil and then vacuum packaging in polyethylene film ($20{\times}30{\times}0.05mm$), and then storage at $-20^{\circ}C$ for 7 days, next thawed and warmed by microwave for 2 minutes} and Steak-2 {vacuum-packaging in polyethylene film ($20{\times}30{\times}0.05mm$), and then storage at $-20^{\circ}C$ for 7 days, after thawed, roasted during 2 minutes in a frying pan wrapped with olive oil}. The factors such as pH, TBA value, amino-N, free amino acid, chemical composition, color value (L, a, b), texture profile, sensory evaluation and viable bacterial count of the olive flounder steak (Steak-1, Steak-2) were measured. From the result of sensory evaluation, Steak-2 showed a bit more high scores than Steak-1 but it was difficult to distinguish significant difference (color, odor, taste, texture and acceptance) between Steak-1 and Steak-2 products.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.175-186
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• 1985

Research situation and recent research activities of the RDA of Korea were reviewed and summarized for rice nurserybed. Sixty five percent of total 784 weed research items were carried out as rice research while only 6 percent was belonged to nurserybed within rice research. The floristic composition based on the degree of dominance significantly affected by herbicide properties, type of nurserybed and seeding itself. Herbicidal phytotoxicity of currently used several herbicides was greatly dependent upon the covering, absorption, germination, and irrigation regimes. The new safening agent "CGA 123 407" (4,6-dichloro-2-phenyl-pyrimidine) permited the safe application of pretilachlor (2-chloro-2',6-diethyl-N-(2-propoxyethyl) acetanilide) as a pre-emergence herbicide without reducing herbicidal efficacy. Several new herbicides, pyrazolate (4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol-5-yl-p-toluenesulphonate), SL-49 (1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-phenacyloxy-pyrazole) MY-93 (S(1-methyl-1-phenethyl)-piperidine-1-carbathioate) and DPX-84 ((methyl 2- ((4,6-dimethoxypyrimidin-2-yl) amino-carbonyl) aminosulfonylmethyl)) benzolate)) performed satisfactorily in terms of safety and herbicidal efficacy for both surface covered and surface pressed nurserybed after herbicide application and thus expected very significant contributions not only for all kind of nurserybeds but also for direct seeding.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.3
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• pp.162-168
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• 2002

The silica uptake of rice plant(Oryza sativa L.) and a potential capacity of paddy soil as a source of silica supply for rice plant was studied under field experimental condition. Amount of Si from irrigation water, rainfall, which was a source of silica supply, and percolating rate of water through paddy soil profile as a source of silica loss from paddy soil, was investigated. Rice plants were grown in three different conditions, which included Control as non-fertilized, RDA's recommandation(NPK, Urea-Fused phophate-Potassium chloride=$110-45-57kg\;ha^{-1}$) and RDA's recommandation with supplement of silicate fertilizer(NPK+Si, Urea-Fused phosphate-Potassium chloride+Si=$110\;N-45\;P_2O_5-57\;K_2O+267.2\;Si\;kg\;ha^{-1}$). An amount of silica supply from rainfall was $0.5kg\;ha^{-1}$ and average amount of silica supplied from irrigation water $42.5kg\;ha^{-1}$, ranging from $28.1kg\;ha^{-1}$ to $58.8kg\;ha^{-1}$. Silica amount percolated through the soil profile have uniform trend comparatively showing $62.9kg\;ha^{-1}$ in Control, $64.8kg\;ha^{-1}$ in NPK treatment and $62.9kg\;ha^{-1}$ in NPK+Si treatment. Silica uptaked by Rice plant was $335.6kg\;ha^{-1}$ in Control, $406.6kg\;ha^{-1}$ in NPK+Si treatment and $471.1kg\;ha^{-1}$ in NPK+Si treatment. The difference between an amount of Si input(from rainfall, irrigation water and silicate fertilizer) and an amount of Si output(percolated Si in soil, uptaked Si by rice plant) was $357.4kg\;ha^{-1}$ in control, $412.1kg\;ha^{-1}$ in NPK treatment and $238.2kg\;ha^{-1}$ in NPK+Si treatment. Results of our study imply that paddy soil is a potential pool as a source of Si supply during growing periods of rice plant.

• Food Science and Preservation
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• v.14 no.1
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• pp.47-53
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• 2007

Soybean curd was mixed with onion powder to develop new foods, and changes in quality characteristics were investigated. The moisture content of onion soybean curd rose as the proportion of onion powder increased Whiteness (as measured by the L value) was high in soybean cud admixed with 0.1% (w/v) onion powder, Redness (the a value) was not significantly altered (the readings were 1.03-1.54) on addition of various onion powder concentrations. Yellowness (the b value) was similarly unaffected (readings 13.00-13.93) when various levels of onion powderwere added. Free sugar analysis showed that glucose was high in soybean curd (67.22 g/100 g) admixed with 0.1% (w/v) onion powder, The main organic acid was tartaric acid, and control organic acids included citric and oxalic acids at high levels. The major free amino acids were L-arginine, ${\gamma}-Amino-n-butyric$ acid, L-histidine, L-glutamic acid, L-serine, L-tyrosine and L-threonine, and amino acid content were high in soybean curd admixed with 0.2% (w/v) onion powder. Major phenolic compounds of onion soybean curd were quercitrin, protocatechuic acid and caffeic acid. The hardness of onion soybean curd was similar to that of the control when onion powder was added to 0.1% or 0.2% (w/v), and decreasedmore onion powder was added. Organoleptic qualities dropped as onion powder levels increased. In summary, onion powder addition to soybean curd is optimal at the 0.2% (w/v) level..

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.315-322
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• 2013

This study was carried out to establish a management program and soil restoration plan through analysis of soil properties and visitor questionnaires in Songrim in Hadong, Korea. Soil bulk density in Songrim was slightly higher in the closed-woodlands ($1.31g/cm^3$) than in the open-woodlands ($1.39g/cm^3$). Soil bulk density in the closed-woodlands was higher in walking trails ($1.74g/cm^3$) than in forest areas ($1.39g/cm^3$), while the rates of pore space were lower in walking trails (42.6%) than in forest areas (50.5%). The soil porosity were lower in the closed-woodlands (34.6%) than in the open-woodlands (42.6%). Soil strength in surface soil was slightly lower in the open-woodlands ($8.5kgf/cm^2$) than in the closed-woodlands ($10.5kgf/cm^2$). The content of organic matter, total nitrogen and exchangeable cations of the woodlands was low compared with the optimum nutrient content for tree growth in Korea forest soil. According to the survey, the objective of visiting in Songrim was to enjoy recreation and landscape views. To conserve pine forest ecosystems in Songrim, the respondents said that it needs to the implement of closed-woodland periods, the establishment of smoking free zone, and the prohibition of garbage throwing and alcohol including disciplinary rules and education. Also the respondents said that pine forest ecosystem in Songrim is relatively sound, but the woodlands require the intensive management to the ecosystem and the introduction of native understory vegetation, such as grasses under pine forest ecosystem. It is recommended to designate the rest-year forest for a proper period in all woodlands to restore the Songrim soil rather than the alternation application between the rest-year for three years or non-rest-year trails, and to open partially the walking trails across the woodlands after the period. In addition, the forest within the woodland is need to designate a long-term rest-year.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1380-1387
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• 2014

The purpose of this study was to develop a mouthwash product with solid fermented oriental medicinal herb (OMH). Solid fermentation of magnolia, liquorice, and cnidium by Phellinus linteus mycelium was carried out successfully when 30% water was added to the medium, whereas 10% brown rice powder was required as an extra nutrient for solid fermentation of mint besides water. The amount of total phenol compounds and DPPH radical scavenging activity of OMH increased significantly (P<0.05) upon solid fermentation. Anti-microbial activities of fermented OMH also increased and were approximately 100-fold greater than those of unfermented samples. Oral pathogens such as Staphylococcus epidermis, Streptococcus pyogenes, Candida albicans, or Streptococcus mutans were used for determination of anti-microbial effects of OMH. Formulation of the mouthwash was developed based on the results of the sensory evaluation. Among seven formulas, the best formula chosen by the sensory evaluation was as follows: mouthwash prepared with 0.075% ethanol extract of solid fermented OMH as a main ingredient, 83.64% hot water extract of mint and clove (100:15, v/v) as a mouthwash base component, and other miscellaneous ingredients, including sodium fluoride, menthol, and surfactants. Data from a consumer's preference test with 30 participants, overall acceptance, and willingness to buy the product developed in this study were all significantly higher for the tested mouthwash compared to mouthwash on the market manufactured with OMH but with a different formula. Duration of freshness of the mouthwash after usage as determined by Breath Checker was not significantly different between the two samples, although the duration of our product was slightly longer than that of the commercial product mentioned above.

• Journal of Gastric Cancer
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• v.6 no.3
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• pp.167-172
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• 2006

Purpose: The laparoscopy assisted gastrectomy has been increasingly reported as the treatment of choice for early gastric cancer. However, expert surgeons, who have performed a conventional open gastrectomy for a long time, tend to have a negative attitude toward laparoscopic procedures. The aim of this study was to determine the learning curve of a laparoscopy assisted distal gastrectomy (LADG) for a surgeon expert in performing an open gastrectomy and to analyze the factors that have an effect on a LADG. Materials and Methods: Between April 2005 and March 2006, 62 patients underwent a LADG with D1+beta lymph-node dissection. The 62 patients were divided into 10 sequential groups with 6 cases in each group (the last group was 8 cases), and the time required to reach the plateau of the learning curve was determined by examining the average operative times of these 10 groups. Other factors, such as sex, BMI, complications, transfusion requirements, the number of retrieved lymph nodes, and change of postoperative hemoglobin level, were also analyzed. Results: With the $5^{th}$ group (after 30 cases), the operative time reached a plateau (average: 170 min/operation). The differences between before the $30^{th}$ case and after the $31^{st}$ case with respect to changes in the postoperative hemoglobin level, the number of retrieved lymph nodes, the transfusion requirements, and the complications rate were not significant. Conclusion: According to an analysis of the operative time, experience with 30 LADGs in patients with early gastric cancer is the point at which the plateau of the learning curve (7 months) is reached. Abundant experience with a conventional open gastrectomy and a well-organized laparoscopic surgery team are important factors in overcoming the learning curie earlier.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.4
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• pp.488-498
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• 2007

The purposes of this study were to: a) provide evidences concerning the effects of emotional leadership b) examine the impacts of emotional leadership on employee-related variables, 'job satisfaction', 'organizational commitment', 'organizational performance' and 'turnover intention', and c) identify a conceptual framework underlying emotional leadership. A survey was conducted from August 23 to November 3, 2005 to collect data from mid-level managers in food service company headquarters (N=219). Statistical analyses were completed using SPSS Win (12.0) for descriptive, reliability, factor and correlation analyses and AMOS (5.0) for confirmatory factor analysis and structural equation modeling. The main results of this study were as follows. First, the managers gave the highest point to their leaders in the emotional leadership competence 'organizational awareness : reading the currents, decision networks, and politics at the organizational level' and gave the lowest point in the emotional leadership competence 'influence: wielding effective tactics for persuasion'. Second, the means of job satisfaction was above the midpoint (3 points). Employees' job satisfaction with 'coworkers' was relatively high. However, the extents of satisfaction with 'payroll' 'promotion', and 'work environment' were relatively low. Third, the organizational commitment was above the midpoint (3 points). In the organizational commitment, 'loyalty' factor was higher than 'commitment' factor. Fourth, the means of organizational performance was above the midpoint. The highest organizational performance variable was 'internal efficiency; trying to reduce cost' and the lowest organizational performance variable was 'internal fairness ; equitable treatment and all are treated with respect with no regard to status and grade'. Fifth, most respondents intended on 'thinking of quitting ; towards turnover process'. Sixth, the test of hypothesis using structural equation modeling found that emotional leadership produced p[Isitive effects on job attitude and job performance. Emotional leadership enhanced job satisfaction and organizational commitment, and in turn, employees' attitude positive effects on organizational performance; emotional leadership also had a direct impact on organizational performance

• Journal of Korean Society of Forest Science
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• v.9 no.1
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• pp.61-74
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• 1969

Forest area in Korea ocupies as much as 68 percent of the total land area, but forest production figure in the statistics is rather trifling: that is about 2 percent of Gross National Production (G.N.P.), on the average. In view of the primary industrial sector, its production only weighs no more than 5 percent of this whole sector. Forest production written above refers only to direct forest income of the whole forest income. For the primary forest products they are in many cases used as raw materials for other interrelated industries. The added value there-from, which arises from round about production Process, in other word, indirect income is of most singnificance. Nevertheless, until nowadays forest production has been merely refered to timber production i, e, direct production but indirect income has never been looked upon. In this regard, calculated indirect forest income by means of input ratio method. The material used were Leontiefls tables of two 1963 and 1966 fiscal years, surveyed and analysed by The Bank of Korea. Indirect forest income calculated were 42,688,200,000 won in 1963 and 74,789,800,000 won in 1966 compared direct forest income of 14,361,000,000 won in 1963 and 17,709,000,000 won in 1966. So far as indirect forest income is considered total forest production indices composed of direct and indirect forest income amount to 8.23% in 1963 and 10.12% in 1966 of Gross National Production. Invisuable forest income which originates from, what we cal, indirect benefit of forestry such as land conservation, flood and drought control, soil run off control, scenic beauty and many others is naturall, not included in the calculation. As already mentioned, primary forest products are, for the most part, utilized as raw materials for other industries, therefore indirect forest income is rather appreciable than direct forest income, contributing for the growth and development of other connected industries. In these points of view, forestry must not be evaluated trifling in deciding industrial importances.