• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1363-1370
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• 2012

In this study, methanol extract and its organic solvent fractions were prepared from Prunus davidiana (Carriere) Franch. fruit. Antioxidative activities, polyphenolic and flavonoid contents, and tyrosinase inhibitory activities were evaluated. Among the fractions, ethyl acetate fraction showed the highest antioxidative activity with $IC_{50}$ values of 5.8 ${\mu}g/mL$ and 88.1 ${\mu}g/mL$ for DPPH radical and nitrite scavenging, respectively, which were comparable to those of ascorbic acid. Further, total flavonoid and polyphenolic contents were highest in the ethyl acetate fraction with $IC_{50}$ values of 244.5 mg/g and 210.2 mg/g, respectively. $IC_{50}$ values for tyrosinase inhibitory activity were 0.310 mg/mL and 0.329 mg/mL for the ethyl acetate and n-butanol fractions, respectively. Based on these results, it is suggested that the ethyl acetate fraction of Prunus davidiana (Carriere) Franch. fruit could be used as a functional material in the food and pharmaceutical industries.

• The Korean Journal of Physiology
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• v.20 no.1
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• pp.1-7
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• 1986

It has been well documented that the peripheral autonomic nervous system plays an important role in exocrine pancreatic secretion. However, the role of the central nervous system in pancreatic function is still obscure even though the central nervous system has been known to control gastrointestinal functions through the autonomic nervous system. Since the reticular formation in the mesencephalone seems to integrate the autonomic function, the present study was undertaken to investigate a possible influence of the reticular formation upon the exocrine pancreatic secretion. Twenty·two albino rats fasted for 24 hours were anesthetized by intraperitoneal injection of urethane in a dose of 1 g/kg, The pancreatic duct was cannulated to collect pancreatic juice and bile juice was diverted to the jejunum. The gastroduodenal junction was ligated to Prevent passage of gastic juice into the duodenum. A pair of electrodes were bilaterally inserted in the reticualr formation of the mesencephalone with aid of a stereotaxic apparatus. When the volume of pancreatic juice secreted for 10 min became constant, the reticular formation was electrically stimulated for 10 min. Parameters of the electical stimulation was 1.3V, 40 Hz and 2 msec. When the pancreatic secretion returned to the level before the electrical stimulation, cervical vagotomy (11 rats) or administration of propranolol (11 rats) in a dose of 0.1 mg/kg through the jugular vein was carried out. Ten minutes after the treatment, the electrical stimulation of the reticular formation was repeated. The brain was fixed by perfusion of 10% formaline solution through the heart, and then placement of the electrode tip was examined histologically. Protein concentration and amylase activity in samples of Pancreatic secretion were measured. The electrical stimulation of the reticular formation significantly increased in volume $({\mu}l/10\;min)$, Protein output $({\mu}g/10\;min)$ and amylase output (U/10 min) in the pancreatic secretion. The stimulatroy effects were not affected by the cervical vagotomy but completely abolished by propranolol. Meantime, it was also observed that both vagotomy and propranolol significantly reduced the pancreatic secretory function. These results indicate that the reticular formation in the mesencephalone may exert a stimulatory effect upon the Pancreatic secretory function not through the vagus nerve but through the sympathetic pathway in anesthetized rats.

• The Korean Journal of Physiology
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• v.22 no.1
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• pp.63-77
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• 1988

This study was carried out to investigate relationships between maximal running time (MRT) and glycogen supercompensation in fast twitch white fibers (white vastus, WV), fast twitch red fibers (red vastus, RV) and slow twitch red fibers (soleus muscle, SM) of endurance-trained rats. Male rats of a Sprague-Dawley strain were divided into the trained groups and untrained groups. Untrained groups were acquired to run on the treadmill 10 minutes for 3 days and remained rest and maintained with mixed diet for 4 weeks. For last 10 days of resting period, the untrained rats were divided into 3 groups i.e. mixed diet (untrained control), high and low carbohydrate (CHO) diet groups. And each group was subdivided into 2 groups, one group was tested for the MRT and the other was sacrificed to measure the blood glucose, blood lactate, glycogen contents of liver and muscles. The experimental groups were trained on treadmill by a modified method of Constable et al. (1984) maintained with mixed diet for 4 weeks. After measurement of MRT of this group, they were also divided into high and low CHO groups and fed with these diet for 2 days and MRT of each group was measured again to see the effect of high or low CHO feeding on the MRT. Each group was maintained with the same diet for next 2 days during which some of the rats were sacrificed at given time intervals for the measurements of blood glucose and lactate, liver and the muscles glycogen. The results were summarized as follows; 1) In the untrained group, there were no significant differences between subgroups in MRT, glycogen conent of SM, RV and WV. But blood glucose concentration and glycogen content of liver of low CHO group were significantly lower than those of mixed diet group. 2) The MRT and glycogen content of SM, RV and WV of trained mixed diet group were significantly increased compared to those of untrained mixed diet group, but there was no significant difference in glycogen content of liver. 3) MRT of trained mixed, high CHO and low CHO groups were $137{\pm}9.8,\;176{\pm}9.8\;and\;129{\pm}7.3\;min$ respectively with the significant difference between them. 4) There were no differences in blood lactate concentrations between the trained high and low CHO groups immediately after maximal running and during recovery period. 5) Glycogen contents in RV and SM of trained high CHO group were significantly increased, and glycogen contents in RV, WV and liver of trained low CHO group were significantly decreased compared to those of trained mixed diet group. 6) Immediately after maximal running, the blood glucose concentrations of trained high CHO and low CHO groups were $73{\pm}4.0\;and\;67{\pm}6.9mg%$ respecitively. The blood glucose of the trained high CHO group was fully recovered within one hour by feeding. But blood glucose concentration of low CHO group was slowly recovered up to $114{\pm}4.1mg%$ after two hours of feeding and maintained. Those values were still significantly lower than that of trained mixed diet group. The synthetic rates of glycogen in liver and muscles during the recovery period followed the similar time course of the blood glucose recoveries in each group. These results suggest that an increase in MRT of trained high CHO group was attributed to the glycogen supercompensation in slow twitch muscle fibers. And a decrease in MRT of trained low CHO may be due to decreased glycogen contents of liver and muscles. The results also suggest that glycogen supercompensation was more evident in slow twitch red fibers of endurance-trained rats and blood glucose is one of the limiting factors of glycogen synthesis.

• The Korean Journal of Physiology
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• v.7 no.2
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• pp.1-8
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• 1973

Though it has been reported by Clements et al. and Avery et al. that the activity of the pulmonary surfactant can be altered by the temperature changes, a conclusive evidence of the effects of temperature on the surfactant system of the lung is yet to come. In the present study, an attempt was made to observe possible effects of a few different degrees of temperature on the activity of the pulmonary surfactant of the rabbit in vivo and in vitro. The rabbit was sacrificed by blood shedding and both lungs were completely removed. The lung washings, obtained by gently lavaging the left lung with saline, was placed at 1) 4C for 1, 5, 10, 15, 30 and 40 days, and 2) 20C for 1, 2, 3, 4, 5 and 7 days for in vitro experiment. For in vivo experiment, the rabbit was placed at 4C for 4, 8, 12 and 24 hours, and the lung lavage was prepared as described above in the in vitro experiment. Tension-area (T-A) diagram of the lung lavage was recorded automatically by a modified. Langmuir-Wilhelmy balance with a synchronized recording system. The surface tensions thus obtained were compared with those of the normal rabbit, and the results are summarized as follows: 1. The maximal surface tension, minimal surface tension and stability index of the normal rabbit lung lavage were $52.5{\pm}2.3\;dynes/cm,\;4.9{\pm}2.3\;dynes/cm$ and 1.65, respectively. 2. In the group where the lung lavage was placed at 4C in vitro, the maximal and minimal surface tensions, and stability index did not show any noticeable changes comparing with the normal values up to 30 days. On the 40th day of the experiment, a tendency of a slight increase in the surface tensions was observed but the change was not significant. 3. When the lung lavage was placed at 20 C in vitro, the maximal surface tension did not show any appreciable change comparing with the normal except on the 7 th day with a slight increase. The minimal surface tension showed an increased value from the 2nd day, and on the 5 th and 7 th experimental day, markedly increased value was observed. The stability index, on the other hand. showed a marked decrease throughout the entire experiment with the value of 0.71 and 0.53 on the 5th and 7 th day, respectively. 4. In the group where the rabbit was placed at 4 C in vivo, the maximal surface tensions and stability index of the lung lavage showed little change from the normal. The minimal surface tension at 12 experimental hour showed a slight increase, but it returned to the normal value at 24 hour.

• Journal of Korean Physical Therapy Science
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• v.18 no.1
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• pp.1-10
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• 2011

Purpose: Study on the effect of the use of Proprioceptive Neuromuscular Facilitation(PNF) method by use of the direction and charge regulation which is the advantage of the Thera-band therapy on the walks and balances in old people and comparison with the result after applying the general PNF technique. Method: The study has been performed on 30 females over 65 years old. The study has been done by dividing the object group in 3 patterns, which are number 1, the comparison group of 10, two ones that are applied the PNF technique using Thera-band and third, the ones that are applied only the PNF technique. For the PNF and the Thera-band using PNF, we have divided the group into Combination of Isotonic technique and the Rhythmical stabilization technique according to the patient's acquaintance pattern and applied them to the patient's body. Evaluation was the balancing ability which was calculated by using the BIODEX Balance system / FRT and for the evaluation of walking ability, we have used the speed of walking for 10M / TUG. Result: In the comparison group of 10, the balancing ability and the walking ability did not change much before and after the experiment, which made it possible to compare the group with the other two easily(p>0.05). For the other two groups, we have recognized the enhancement both in the balancing ability and the walking ability, but they did not know much difference between themselves(p<0.05). Conclusion: Though there were not a big difference in the sense of improvement between the Thera-band using PNF and the PNF technique only, we could infer that these two therapy has enhanced much in the walking and balancing ability for people over 65 and through these result we can foresee that not only using the method shown in this study but also by using many advantages of Thera-band, we could diminish the tiredness of healer, enhance the efficiency of exercise in them and also by forming self training program for older people we could help them build the prevention program from falls.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.411-427
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• 2006

This study aimed to recognize characteristics of groundwater flow in fractured bedrocks based on zonal pump-ing tests, slug tests, water quality logs and borehole TV camera logs conducted on two boreholes (NJ-11 and SJ-8) in the city of Naju. Especially, the zonal pumping tests using sin91e Packer were executed to reveal groundwater flow characteristics in the fractured bedrocks with depth. On borehole NJ-11, the zonal pumping tests resulted in a flow dimension of 1.6 with a packer depth of 56.9 meters. It also resulted in lower flow dimensions as moving to shallower packer depths, reaching a flow dimension of 1 at a 24 meter packer depth. This fact indicates that uniform permissive fractures take place in deeper zones at the borehole. On borehole SJ-8, a flow dimension of 1.7 was determined at the deepest packer level (50 m). Next, a dimension of 1.8 was obtained at 32 meters of packer depth, and lastly a dimension of 1.4 at 19 meters of packer depth. The variation of flow dimension with different packer depths is interpreted by the variability of permissive fractures with depth. Zonal pumping tests led to the utilization of the Moench (1984) dual-porosity model because hydraulic characteristics in the test holes were most suitable to the fractured bedrocks. Water quality logs displayed a tendency to increase geothermal temperature, to increase pH and to decrease dissolved oxygen. In addition, there was an increasing tendency towards electrical conductance and a decreasing tendency towards dissolved oxygen at most fracture zones.

• The Journal of Engineering Geology
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• v.25 no.4
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• pp.557-576
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• 2015

Groundwaters in granite, gneiss, and two-mica granite formations, including faults, in the Hoengseong area are examined to determine the relationship between their uranium and radon-222 contents and rock types. The chemical compositions of 38 groundwater samples and four surface water samples collected in the study area were analyzed. Sixteen of the samples showing high uranium and radon-222 contents were repeatedly analyzed. Surface radioactivities were measured at 30 points. The uranium and radon-222 concentrations in the groundwater samples were in the ranges of 0.02-49.3 μg/L and 20-906 Bq/L, respectively. Four samples for uranium and 35 samples for radon had concentrations exceeding the alternative maximum contaminant level of the US EPA. The chemical compositions of groundwaters indicated Ca(Na)-HCO₃ and Ca(Na)-NO₃(HCO₃+Cl) types. The pH values ranged from 5.71 to 8.66. High uranium and radon-222 contents in the groundwaters occurred mainly at the boundary between granite and gneiss, and in the granite area. The occurrence of uranium did not show any distinct relationship to that of radon-222. The radon-222, an inert gas, appeared to be dissolved in the groundwater of the aquifer after wide diffusion along rock fractures, having been derived from the decay of uranium in underground rocks. The results in this study indicate that groundwater of neutral or weakly alkaline pH, under oxidizing conditions and with a high bicarbonate content is favorable for the dissolution of uranium and uranium complexes such as uranyl or uranyl-carbonate.

• Journal of Environmental Impact Assessment
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• v.28 no.6
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• pp.604-615
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• 2019

In this study, we produce a new type of the algae soil conditioner(ASC) using discarded algae biomass through a composting process and evaluate its nutritional characteristics. As the main ingredient, the ASCs used algae biomass collected through the coagulation-floating method and made by adding a variety of additional supporting materials (sawdust, pearlite, oilcake etc.). ASCs were divided into 0% in blank, 11.7% in ASC1, 21.6% in ASC2, 37.6% in ASC3, 59.5% in ASC4, and composted during 127 days. ASCs showed a sharp increase in temperature by aerobic microbial reaction, and 6~7 high and low temperature peaks were observed. As a result of physicochemical analysis, mineralization proceeded according to decomposing the organic matter and there was a marked increase not only in macronutrients (TN, P₂O₅, K₂O), but also in secondary macronutrients (CaO, MgO). The microbial community change was found in stage 1 (bacteria, filamentous fungi) → stage 2 (actinomycetes, bacteria) → stage 3 (Bacillus sp.), depending on the maturation process. It was estimated that microbial transition was closely related to temperature change and nutritional behavior. The quality of soil conditioner can be determined according to the maturity of compost process, and it was determined that effective microbial activity could be induced by controlling algae biomass below 59.5% in this study. In conclusion, we found out the possibility of manufacturing and utilizing soil conditioner recycled algae biomass and if further technological development is made on the basis it can be used as an effective soil conditioner.

• Journal of Elementary Mathematics Education in Korea
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• v.10 no.1
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• pp.67-87
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• 2006

This study is to recognize a problem in the practice of performance assessment in elementary school, and to find out some suggestive points for improvement of teaching·learning method in elementary mathematics through assessment by reducing time restriction according to assessment through the practice of self-assessment, peer-assessment and observation, and then by reflecting the results of assessment on teaching learning plan. For that, the questions of study set up are as follows ; 1. How should self-assessment and peer-assessment be applied to in elementary mathematics assessment? 2. How should the time for 'let's play an interesting game' be managed for assessment of elementary mathematics? 3. How should the results of assessment be reflected on the Process of teaching and learning of mathematics? To solve these problems, a researcher of this thesis performed self-assessment, peer-assessment on 40 students of second grade under her charge as a class teacher, and applied observation in the time management process for 'let's play an interesting game' for a semester. self-assessment was made by mathematics journal, self-assessment chart, peer-assessment was by the analysis of conversation record among students in the situations of assessment, and observation was by observation of activity when playing with the results data of play analyzed. the concrete methods of application as follows ; First, mathematics journal was applied $1{\sim}2$ times by each unit with reconstruction into the level of second grade on the basis of the preceding-study models. Second, peer-assessment was applied to the unit-assessment time and the play-activities time by the method of recording·analyzing the contents of conversation among students in the process of assessment. Third, mathematical attitude & dispositions of students making use of the self- assessment table were examined referring to the teaching learning plan. Fourth, the time management for 'let's play an interesting game' was made through the prior recognition of play method and the joyful play-activities by use of the play-plate. Assessment depended on analysis of play-activities results of students making use of an observation form. Fifth, the results of self-assessment, peer-assessment, and observation were analyzed, and then they were made use of as self-observation data, of teacher her/his self, or teaching·learning improvement data. Students' self-assessment datum (mathematics diary, self-assessment sheets, conversation contents in the process of assessment) and observation materials (check lists, Play-activity result materials, conversation contents in the process of play) obtained in the process of application was analyzed as follows ; 1. From the practice of self-assessment in form of mathematics journal, I could obtain not only datum showing how much students was understanding the learning aims by unit time and to any degree they reached but also information about their response to learning datum and favorable type of learning. 2. Assessment by self-assessment chart was useful in planning the mathematics teaching learning process because it helps ascertain mathematical attitude & dispositions of students. 3. Through the application of peer-assessment, students had the opportunity of communicating with other students looking back on his/her explaining process, and teachers could obtain basic materials for assessment of students. 4, In case of time management for 'let's play an interesting game', there was natural extension of play made through time-security by prior looking into the method of play-activity, and then, for a remained time, by making children play a new game. 5, I could easily record the activities of students by use of the observation. form, and make use of it as basic data for descriptive assessment. 6, Each kinds of data obtained from the results of assessment was helpful for securing self-observation materials in the process of teaching learning and for their betterment in mathematics subject. However, because they were in the second grade of elementary school and there was an individual difference, some students could not make use of mathematics diary or self-assessment form properly. In case of these students, assessment data would be obtained through interview or observation. And for effective operation of play, its purpose & method and matters that demand special attention when play-acting should be clearly guided. Also, when applying an effective play in addition to play activities in textbook, to lessons, interesting mathematics lessons could be guided.

• Applied Microscopy
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• v.29 no.1
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• pp.25-41
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• 1999

The experiment was performed to study the morphological responses of the renal glomeruli of the mice after administration of 5-fluorouracil or mitomycin C. 5-fluorouracil (60 mg/kg) or mitomycin-C $(400{\mu}g/kg)$ were injected subcutaneously to the animals every other day, and animals were sacrificed at 4 days or 7 days following the first injections. Pieces of tissues were observed with a JEM 100CX-II electron microscope. The observed results were as follows: 1. In the fourth day following the first injection of 5-fluorouracil or mitomycin C, components of the renal glomeruli of the mice are looked compact since they were filled with the widened the mesangium, and showed narrowing lumen of glomerular capillaries and of urinary spaces. The changes were more significant in the mitomycin C treated mice. 2. In the 5-fluorouracil treated mice, morphological changes of glomeruli were generally recovered in the seventh day, whereas the glomeruli of the mitomycin C treated mice have not shown general recovery. 3. In the fourth and seventh days following the first injection of mitomycin C, in the renal glomeruli of the mice, swollen endothelial cells, and protruded mesangeal cells into the capillary lumen are frequently observed. 4. In the fourth day following the first injection of mitomycin C, in the glomerular basal lamina of the mice, the electron densities of the lamina rara interna and the lamina rara externa were similar to the density of the lamina densa and the expanded lamina rara interna were often seen. From the above results, it is suggested that the cytotoxic effects of the mitomycin C on renal glomeruli are more severe as compared with those of 5-fluorouracil.