• Korean Journal of Poultry Science
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• v.15 no.1
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• pp.1-19
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• 1988

A study was carried out to investigate meat production ability of Korean native Ogol fowl (Natural Monument No, 265). The aims of this study were to provide basal data necessary for preserve of purebred and improvement of meat production ability of this breed. A total 300 chickens were used in this study. All the chickens were ad libitum fed broiler starter during period from 0 to 4 weeks of age and broiler finisher during period from 5 to 16 weeks of age. The investigated items are as follows; body weight; growth rate: weight of edible end inedible parts; and body shape components. The results obtained are summarized as follows. 1. Average body weight in male, female, and unsexed, of native Ogol fowls were $659.0{\pm}154.9$, $588.3{\pm}68.0$ and $623.7{\pm}121.9$ at 8 weeks of age, and $938.1{\pm}72.6$, $810{\pm}104.4$ and $874.1{\pm}109.4$g at 10 weeks of age, respectively. 2. The growth rates, unsexed, during periods 2~4, 4~6, 6~8 and 8~10 weeks of age were 166, 106, 41 and 40%, respectively. 3. The growth pattern of total edible parts in both sexes were highly significant by weeks. Total weight of edible parts in male and female were $395.4{\pm}$ and $355.6{\pm}42.0$g at 8 weeks of age, $597.5{\pm}$47.2 and $518.7{\pm}98.5$69.7g at 10 weeks of age. Percentage of total edible parts, unsexed, were 60~63% of body weight during periods from 8 to 10 weeks of age. 4. Edible giblet, unsexed, at age of 8 and 10 weeks were 4~6% of body weight. 5. Percentage of body weight of inedible part were on the decreased by weeks. The amount of blood blooded, feather plucked, inedible viscera and total inedible parts, unsexed, at 8 weeks of age were 4, 7, 12 and 31% of live body weight, respectively. 6. Except breast angle and shank diameter, the other body shape components significantly grew from 2 to 10 weeks of age. Different between male and female at 8 weeks of age were significant in breast girth, keel length, drumstick girth and shank diameter. 7. In both sexes, highly significant differences were found in the correlation coefficients between live body weight and several other body shape component, i. e., breast girth, drumstick girth, and edible part.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.118-127
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• 1985

The grain temperature is a crucial factor determining the deterioration rate of stored grain. Therefore, it is used to be predicted in order to evaluate the various stored methods rapidly and inexpensively. In this study, a mathematical model was developed to simulate the temperatures of grain stored in a cylinderical bin. It was formulated for the two dimensional heat transfer by the finite difference method. Then, it was verified statistically using the actual test deta and the predicted. The changes of grain temperature were analyed using the simulated data of one year for a safe stoarge and the following results were obtained: 1. Simulation model developed by the finite difference method was validated with the actual and the predicted grain temperatures and it's result showed that it could predict the grain temperature of storage bin reasonably well. 2. Grain temperature near the wall of storage bin were changed with $6-7^{\circ}C$ higher then average atmospheric temperature from June to September. Therefore, the parts of stored grain near the wall is supposed to be deteriorated fast. 3. When the dimension of bin diameter is about the same as the bed height, the changes of grain temperature of radial direction was higher than the verticals. 4. The predicted temperature showed that the grain temperature of which were from the end of April to mid October were higher than the safe storage limit at Yusung, Korea.

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.23-30
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• 1968

Tissue homogenates of 12 kinds of human cancer tissues were incubated separately in medium containing $C^{14}-1-glucose$ and $C^{14}-6-glucose$ as a substrate in order to observe the oxidative pathway of glucose in the tumor tissues. At the end of 3 hours incubation in the Dubnuff metabolic shaking incubator, respiratory $CO_2$ samples trapped by alkaling which was placed in the center well of incubation flask were analysed for total $CO_2$ production rates and their radioactivities. The tissue homogenate samples after incubation were analyzed for their concentrations of glucose, lactate and pyruvate. Calculations were made on the glucose consumption rate and accumulation rates of lactate and pyruvate. Fractionation of oxidative pathway of glucose was carried out by calculating $C^{14}O_2 yields from C-1 and C-6 carbon of glucose. The following results were obtained. 1. In 12 kinds of human cancer, total $CO_2$ production rates were less than $8{\mu}M/gm$ except 2 cases. These lower values impressed that oxidative metabolism in the tumor tissues generally inhibited as compared with that in normal tissues. On the other hand, fractions of $CO_2$ derived from glucose to total $CO_2$ production rates (RSA) were less than 10% in every case. These facts showed that oxidation of glucose into $CO_2$ was remarkably inhibited in the tumor tissues. 2. Factions of glucose disappeared into $CO_2\;(RGD_{CO_2})$, lactate $(RGD_L)$, pyruvate $(RGD_P)$ to glucose consumption rates were as follows. $RGD_{CO_2}$ were less than 2% in cases of in this experiment and $RGD_L$ showed more than 5% except in 2 cases. These facts showed that anaerobic degradation of glucose into 3 carbon compounds was easily proceeded but further degradation into $CO_2$ via the TCA cycle was greatly inhibited resulting in accumulation of lactate. There are large variation in values of $RGD_P$ in different kinds of tumor tissue but relatively higher values in $RGD_{CO_2}$ were obtained in the tumor tissues as compared with those of normal tissues. 3. The oxidative pathway of glucose in tumor tissues were analyzed from the values of RSA which were obtained in $C^{14}-1\;and\;C^{14}-6-glucose$ incubation experiments. It was found that 3% of $CO_2$ derived from glucose were oxidized via the principal EMP-TCA cycle and the remainder were via alternate pathway such as HMP in the liver cancer and values in other cancer tissues were as follows; 4% in the tongue cancer, 6% in the colon cancer, 6% in the lung cancer, 9% in the stomach cancer, 11% in the ovarian cancer, 12% in the neck tumor, 22% in the uterine cancer, 22% in the bladder tumor, 32% in the spindle cell sarcoma and 65% in the brain tumor. These values except later 2 cases showed less than 30% which is the lowest value among the normal tissues. Even in the brain tumor in which showed highest value in the tumor group. It is reasonable to suppose that this fraction was remarkably decreased because values in normal brain tissue was more than 90%. From the above data, it was concluded that in tumor tissues, oxidation of glucose via TCA cycle was greatly inhibited but correlation between degree of inhibited oxidation of glucose via TCA cycle and malignancy of tumor were not clarified in this experiments.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.827-838
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• 2017

Twenty male soccer players volunteered as the experimental subjects. The subjects were randomly assigned to the "Winter training with Cornus officinalis extract intake group"(WCI; n=10) and "Winter training group"(WT; n=10). The variables of blood fatigue substance, muscle damage and liver function where measured in all the subjects before the start of the Cornus officinalis intake after at the end of the 4 weeks winter training. Winter training program was proceeded with 6 days a week for 4 weeks. Exercise intensity was measured using the HRR(70~95%). Changes in the heart rate were also measured with the Polar. WCI group were ingested 80 mL of Cornus officinalis extract after every breakfast and dinner for 4 weeks. The test data were analyzed by paired t-test, and independent t-test(%diff), and the alpha level of p<.05 was set for all tests of significance. Lactate in WCI group had significantly decreased, and the changes between the groups were significantly lower in the WCI group than in the WT group. Ammonia in WCI group had significantly increased. CK in WCI group had significantly decreased. LDH in both group had significantly decreased. AST in WCI group had significantly decreased, and the changes between the groups were significantly lower in the WCI group than in the WT group. ALT in WCI group had significantly decreased. In conclusion, the results of this study show that Cornus officinalis extract seem to have a positive influence on blood fatigue substance, muscle damage and liver function. Therefore Cornus officinalis extract is considered to be able to contribute an ergogenic aids.

• Tuberculosis and Respiratory Diseases
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• v.56 no.5
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• pp.523-531
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• 2004

Background : Bronchoscopy in patients on mechanical ventilation is being performed much more frequently. However, there is little data on the changes in physiologic parameters and no established mechanical ventilation protocol during bronchoscopy. A decreasing or the removal of positive end-expiratory pressure (PEEP) during bronchoscopy may precipitate severe hypoxemia and/or derecruitment. Methods : Our standardized mechanical ventilation protocol, without changing the PEEP level, was used during bronchoscopy. The physiological parameters were measured during the bronchoscopic procedure. Results : During bronchoscopy, respiratory acidosis, elevation of peak pressure, elevation of heart rate and auto-PEEP were developed, but were reversible changes. Procedure-related gross barotraumas or other severe complications did not developed. Conclusion : No serious complications developed during bronchoscopy under our standardized mechanical ventilation protocol when the PEEP level remained unchanged. The procedure time should be kept to a minimum to decrease the exposure time to undesirable physiological changes.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.773-780
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• 1999

Background: It has been demonstrated that brief periods of calcium depletion and repletion (calcium-free preconditioning, CP) have cardioprotective effects as seen in ischemic preconditioning(IP) which enhances the recovery of post-ischemic contractile dysfunction and reduces the incidence of reperfusion-induced arrhythmia or infarct size after a prolonged ischemia. In the present study, we tested this paradoxical phenomenon in isolated rabbit hearts. Material and Method: Hearts isolated from New Zealand white rabbits(1.5∼2.0 Kg body weight) were perfused with Tyrode solution using the Langendorff technique. After stabilizing the baseline hemodynamics, the hearts were subjected to 45 minutes of global ischemia followed by 120 minutes of reperfusion with IP(IP group, n=7) or without IP (ischemic control group, n=7). IP was induced by a single episode of 5 minutes global ischemia and 10 minutes reperfusion. In the CP group(n=7), the hearts were subjected to perfusion with Tyrode solution with calcium depletion for 5 minutes and repletion for 10 minutes, and 45 minutes of ischemia and 120 minutes of reperfusion. Left ventricular function including developed pressure, dP/dt, heart rate, left ventricular end-diastolic pressure and coronary flow was measured. Infarct size was determined by staining with 1% triphenyltetrazolium chloride and planimetry. Data were analyzed by a one-way analysis of variance and Tukey's post-hoc test. Result: In comparison with the ischemic control group, IP significantly enhanced the recovery of the left ventricular function including the left ventricular developed pressure, contractility, and coronary flow; in contrast, these functional parameters of the CP group tended to be lower than those of the ischemic control group. However, the infarct size was significantly reduced by IP or CP(p<0.05). Conclusion: These results suggest that in isolated Langendorff-perfused rabbit heart model, CP(induced by single episode of 5 minutes calcium depletion and 10 minutes repletion) could not improve the post-ischemic contractile dysfunction(after a 45-minute global ischemia) but it has an infarct size-limiting effect.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.1
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• pp.253-270
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• 2023

Research on investment determinants of accelerators, which are attracting attention by greatly improving the survival rate of startups by providing professional incubation and investment to startups at the same time, is gradually expanding. However, previous studies do not have a theoretical basis in developing investment determinants in the early stages, and they use factors of angel investors or venture capital, which are similar investors, and are still in the stage of analyzing importance and priority through empirical research. Therefore, this study verified for the first time in Korea the discrimination and effectiveness of investment determinants using accelerator investment determinants developed based on the business model innovation framework in previous studies. To this end, we first set the criteria for success and failure of startup investment based on scale-up theory and conducted a survey of 22 investment experts from 14 accelerators in Korea, and secured valid data on a total of 97 startups, including 52 successful scale-up startups and 45 failed scale-up startups, were obtained and an independent sample t-test was conducted to verify the mean difference between these two groups by accelerator investment determinants. As a result of the analysis, it was confirmed that the investment determinants of accelerators based on business model innovation framework have considerable discrimination in finding successful startups and making investment decisions. In addition, as a result of analyzing manufacturing-related startups and service-related startups considering the characteristics of innovation by industry, manufacturing-related startups differed in business model, strategy, and dynamic capability factors, while service-related startups differed in dynamic capabilities. This study has great academic implications in that it verified the practical effectiveness of accelerator investment determinants derived based on business model innovation framework for the first time in Korea, and it has high practical value in that it can make effective investments by providing theoretical grounds and detailed information for investment decisions.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.662-673
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• 1999

Background : Pressure-controlled ventilation (PCV) is frequently used recently as the initial mode of mechanical ventilation in the patients with respiratory failure. Theoretically, because of its high initial inspiratory flow, pressure-controlled ventilation has lower peak inspiratory pressure and improved gas exchange than volume-controlled ventilation (VCV). But the data from previous studies showed controversial results about the gas exchange. Moreover, the comparison study between PCV and VCV with various inspiration : expiration time ratios (I : E ratios) is rare. So this study was performed to compare the respiratory mechanics and gas exchange between PCV and VCV with various I : E raitos. Methods : Nine patients receiving mechanical ventilation for respiratory failure were enrolled. They were ventilated by both PCV and VCV with various I : E ratios (1 : 2, 1 : 1.3 and 1.7 : 1). $FiO_2$, tidal volume, respiratory rate and external positive end-expiratory pressure (PEEP) were kept constant throughout the study. After 20 minutes of each ventilation mode, arterial blood gas, airway pressures, expired $CO_2$ were measured. Results : In both PCV and VCV, as the I : E ratio increased, the mean airway pressure was increased, and $PaCO_2$ and physiologic dead space fraction were decreased. But P(A-a)$O_2$ was not changed. In all three different I : E ratios, peak inspiratory pressure was lower during PCV, and mean airway pressure was higher during PCV. But $PaCO_2$ level, physiologic dead space fraction and P(A-a)$O_2$ were not different between PCV and VCV with three different I : E ratios. Conclusion : There was no difference in gas exchange between PCV and VCV under the same tidal volume, frequency and I : E ratio.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.363-373
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• 2010

"Curve number" (CN) indicates the runoff potential of an area. The US Soil Conservation Service (SCS)'s CN method is a simple, widely used, and efficient method for estimating the runoff from a rainfall event in a particular area, especially in ungauged basins. The use of soil maps requested from end-users was dominant up to about 80% of total use for estimating CN based rainfall-runoff. This study introduce the use of soil maps with respect to hydrologic and watershed management focused on hydrologic soil group and a case study resulted in assessing effective rainfall and runoff hydrograph based on SCS-CN method in a small watershed. The ratio of distribution areas for hydrologic soil group based on detailed soil map (1:25,000) of Korea were 42.2% (A), 29.4% (B), 18.5% (C), and 9.9% (D) for HSG 1995, and 35.1% (A), 15.7% (B), 5.5% (C), and 43.7% (D) for HSG 2006, respectively. The ratio of D group in HSG 2006 accounted for 43.7% of the total and 34.1% reclassified from A, B, and C groups of HSG 1995. Similarity between HSG 1995 and 2006 was about 55%. Our study area was located in Sosu-myeon, Goesan-gun including an approx. 44 $km^2$-catchment, Chungchungbuk-do. We used a digital elevation model (DEM) to delineate the catchments. The soils were classified into 4 hydrologic soil groups on the basis of measured infiltration rate and a model of the representative soils of the study area reported by Jung et al. 2006. Digital soil maps (1:5,000) were used for classifying hydrologic soil groups on the basis of soil series unit. Using high resolution satellite images, we delineated the boundary of each field or other parcel on computer screen, then surveyed the land use and cover in each. We calculated CN for each and used those data and a land use and cover map and a hydrologic soil map to estimate runoff. CN values, which are ranged from 0 (no runoff) to 100 (all precipitation runs off), of the catchment were 73 by HSG 1995 and 79 by HSG 2006, respectively. Each runoff response, peak runoff and time-to-peak, was examined using the SCS triangular synthetic unit hydrograph, and the results of HSG 2006 showed better agreement with the field observed data than those with use of HSG 1995.

• Journal of Chest Surgery
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• v.32 no.7
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• pp.603-612
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• 1999

Background : It has been documented that brief repetitive periods of ischemia and reperfusion (ischemic preconditioning, IP) enhances the recovery of post-ischemic contractile function and reduces infarct size after a longer period of ischemia. Many mechanisms have been proposed to explain this process. Recent studies have suggested that transient increase in the intracellular calcium may have triggered the activation of protein kinase C(PKC); however, there are still many controversies. Accordingly, the author performed the present study to test the hypothesis that preconditioning with high concentration of calcium before sustained subsequent ischemia(calcium preconditioning) mimics IP by PKC activation. Material and Method : The isolated hearts from the New Zealand White rabbits(1.5∼2.0 kg body weight) Method: The isolated hearts from the New Zealand White rabbits(1.5∼2.0 kg body weight) were perfused with Tyrode solution by Langendorff technique. After stabilization of baseline hemodynamics, the hearts were subjected to 45-minute global ischemia followed by a 120-minute reperfusion with IP(IP group, n=13) or without IP(ischemic control, n=10). IP was induced by single episode of 5-minute global ischemia and 10-minute reperfusion. In the Ca2+ preconditioned group, perfusate containing 10(n=10) or 20 mM(n=11) CaCl2 was perfused for 10 minutes after 5-minute ischemia followed by a 45-minute global ischemia and a 120-minute reperfusion. Baseline PKC was measured after 50-minute perfusion without any treatment(n=5). Left ventricular function including developed pressure(LVDP), dP/dt, heart rate, left ventricular end-diastolic pressure(LVEDP) and coronary flow(CF) was measured. Myo car ial cytosolic and membrane PKC activities were measured by 32P-${\gamma}$-ATP incorporation into PKC-specific pepetide. The infarct size was determined using the TTC (tetrazolium salt) staining and planimetry. Data were analyzed using one-way analysis of variance(ANOVA) variance(ANOVA) and Tukey's post-hoc test. Result: IP increased the functional recovery including LVDP, dP/dt and CF(p<0.05) and lowered the ascending range of LVEDP(p<0.05); it also reduced the infarct size from 38% to 20%(p<0.05). In both of the Ca2+ preconditioned group, functional recovery was not significantly different in comparison with the ischemic control, however, the infarct size was reduced to 19∼23%(p<0.05). In comparison with the baseline(7.31 0.31 nmol/g tissue), the activities of the cytosolic PKC tended to decrease in both the IP and Ca2+ preconditioned groups, particularly in the 10 mM Ca2+ preconditioned group(4.19 0.39 nmol/g tissue, p<0.01); the activity of membrane PKC was significantly increased in both IP and 10 mM Ca2+ preconditioned group (p<0.05; 1.84 0.21, 4.00 0.14, and 4.02 0.70 nmol/g tissue in the baseline, IP, and 10 mM Ca2+ preconditioned group, respectively). However, the activity of both PKC fractions were not significantly different between the baseline and the ischemic control. Conclusion: These results indicate that in isolated Langendorff-perfused rabbit heart model, calcium preconditioning with high concentration of calcium does not improve post-ischemic functional recovery. However, it does have an effect of limiting(reducing) the infart size by ischemic preconditioning, and this cardioprotective effect, at least in part, may have resulted from the activation of PKC by calcium which acts as a messenger(or trigger) to activate membrane PKC.