• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.671-676
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• 2015

The aim of this thesis was to develop PBL(Problem-Based-Learning) problems to supply the problems to classes and to confirm the effectiveness of PBL for PBL applications to element design in engineering schools. Modern industrial society needs competent people with abilities in cooperative learning, self-controlling learning, united knowledge application, and creative problem-solving. Universities need to offer opportunities for improving the problem-solving ability and cooperative learning to learners to train competent people that society demands. PBL activity is a proper learning method for the execution of the above offer. The study subjects were 32 sophomore students in H University who took 'Engineering design 1', which is Element design. Five PBL problems were applied to the class for 15 weeks. They wrote and submitted a reflective journal when they finished the every given PBL activity. In addition, they wrote a class evaluation form after the $5^{th}$ PBL problem's activity ended. The study showed that the students experienced the effectiveness of PBL in many fields, such as the comprehension of the studied contents(71.87%), the comprehension of cooperative learning (87.5%), authentic experience, problem-solving skills (90.63%), presentation skills (96.87%), communication ability, self-directed study ability, and confidence (96.87%). The students realized that PBL learning activities are important because students could develop into future intelligent engineers that modern industrial society demands through PBL learning activities.

• The Journal of Korean Medicine
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• v.26 no.2 s.62
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• pp.217-230
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• 2005

Objectives: Chungpaesagan-tang (CPSGT), which is frequently used for treating patients of cerebrovascular disease, has not been reported by clinical doctors concerning the effect of neuronal aptosis caused by brain ischemia. To study the effect of CPSGT on focal cerebral ischemia in normal and diabetic rats and SHR, focal cerebral ischemia was induced by transient MCAO, and after onset CPSGT was administrated. Methods: Rats (Sprague-Dawley) were divided into four groups: sham-operated group, MCA-occluded group, CPSGT­administrated group after MCA occlusion, and normal group. The MCA was occluded by intraluminal method. CPSGT was administrated orally twice (l and 4 hours) after middle cerebral artery occlusion. All groups were sacrificed at 24 hours after the surgery. The brain tissue Was stained with $2\%$ triphenyl tetrazolium chloride (TTC) or $1\%$ cresyl violet solution, to examine effect of CPSGT on ischemic brain tissue. The blood samples were obtained from the heart.~. Tumor necrosis $factor-\alpha$ level and interleukin-6 level of serum was measured from sera using enzyme-linked immunoabsorbent assay (ELISA). Then changes of immunohistochemical expression of $TNF-\alpha$ in ischemic damaged areas were observed. Results: In NC+MCAO+CP and DM+MCAO+CP, CPSGT significantly (p<0.01) decreased the number of neuron cells compared to the control group. CPSGT markedly reduced (p<0.01) the infarct size of the forebrain in distance from the interaural line on cerebral ischemia in diabetic rats. CPSGT significantly reduced the $TNF-\alpha$ expression in penumbra region of damaged hemisphere in diabetic rats. Conclusions: CPSGT had a protective effect on cerebral ischemia in SD rats, especially in diabetic rats compared with normal SD rats.

• Atmosphere
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• v.29 no.4
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• pp.403-416
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• 2019

Precipitation samples were collected at the GAW Stations in Anmyeon-do and Gosan for 10 years (2008-2017) to analyze pH, electrical conductivity and NH₄⁺, Na⁺, K⁺, Mg²⁺, Ca²⁺, SO₄^2-, NO₃^-, Cl^-, and F^- ions. From the analysis, the correlation between pH and rainfall, the composition of precipitation and comparison with other regions, and the results of neutralization characteristics by seasonal and pH were determined. In the comparison of ion balance and conductivity for the validation of analytical data, the correlation coefficients were within the range of 0.996~0.999, implying good linear relationship. The volume-weighted pH of the Anmyeon-do and Gosan areas were 4.7 and 4.9, respectively. The pH of the rainfall was affected by washout and rainout in both areas. The ionic strength of precipitation at Anmyeondo and Gosan were 0.42 ± 0.63 mM and 0.37 ± 0.75 mM, indicating about 27.6% and 35.3% of the total precipitation as per a pure precipitation criterion (10^-4 M), respectively. The composition ratio of ionic species were 44.7% and 57.5% for marine sources (Na⁺, Mg²⁺, Cl^-), 40.6% and 22.2% for the secondary inorganic components (NH₄⁺, nss-SO₄^2-, NO₃^-), and 5.6% and 4.0% for the soil source (nss-Ca²⁺), respectively. The neutralization factor of Anmyeon-do and Gosan were 0.43~0.65 and 0.34~0.48, and the neutralization factors of calcium carbonate were 0.15~0.34 and 0.25~0.30, respectively. Thus, both regions have the highest rate of neutralization caused by ammonia. As pH increased in Anmyeon-do and Gosan, change in calcium carbonate became greater than that in ammonia.

• Journal of radiological science and technology
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• v.29 no.3
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• pp.147-155
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• 2006

The crystal structures of fully dehydrated $K_3Na_8H-A(R_1=0.0478,\;R_2=0.0458\;and\;a=12.257(1){\AA})$ have been studied by single-crystal x-ray diffraction methods in the cubic space group. Pm3m in order to understand the structure of the zeolite as a gas storage medium and the mechanisms based on the encapsulation and decapsulation processes of gas molecules. In the crystal structures of dehydrated $K_3Na_8H-A$, three $K^+$ ions per unit cell are located on the 8-oxygen ring(0.0, 0.4531, 0.4531) and eight $Na^+$ ions per unit cell are located near the centers of 6-oxygen rings. Each $K^+$ ions on the 8-ring is $2.87(2){\AA}$ and $2.79(1){\AA}$ away from two kinds of framework oxygen atoms. These values are more realistic than previously known values in $K_{12}Na-A$. The exact positions of $K^+$ ions are ca. $0.8{\AA}$ away from the centers of the 8-rings which are previously reported as the preferred location of $K^+$ ions. Because the zeolites frameworks are stabilized as the results, more effective controls of gas molecules at encapsulation, decapsulation, and storage are achieved. Additionally, the available storage volumes are also maximized and more volume of gases can be stored in the materials. Therefore, oxygen storage bottles in hospital can be minimized and portable oxygen bottles for patients in emergency can be developed by using the materials.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.134-138
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• 2011

This study was conducted to evaluate the effects of seeding time of ryegrass+hairy vetch on the nutrient contribution and growth of the crops. in order to develop utilization of cover crops as an organic nutrient source in a pear orchard. The study was conducted at a diligent farmer in Boseong in Chonnam, and the both ryegrass and hairy vetch applied on 1) 27 September, 2) 15 October, 3) 8 November, and 4) 10 December of 2008 as a cover crop treatment. Sod culture was refereed as a control. Growth of ryegrass was not affected by seeding time, but hairy vetch had fewer leaf and shoot number as seeding time advanced from September to December, and the similar trend was observed for the dry weight of the crops by seeding time. Seeding of cover crop on September was 2.6 times greater dry weight than those of the sod culture (362 kg/10a). Higher N concentration in cover crops occurred on early seeding time, and estimated N contribution from the cover crops was 16.9 kg/10a, which was 2.6 times greater than those of sod culture. $P_2O_5$ production from the cover crops was the greatest on seeding of October, and $K_2O$ production increased at earlier seeding time.

• Journal of Sericultural and Entomological Science
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• v.52 no.1
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• pp.1-5
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• 2014

This study was performed to determine the whitening effect of organic solvent extracts from the centipede, Scolopendra subspinipes mutilans. We prepared different concentrations (50%, 70% and 100%) of ethanol, methanol, 100% ethyl acetate and water extracts. We tested melanin inhibitory effect and tyrosinase activity using B16/F10 melanoma cell. As a result, treatment of organic solvent extracts is decreased the biosynthesis of melanin and tyrosinase activity to 36 ~ 86%. Especially the 70% ethanol extracts was the most effective in B16/F10 melanoma cells. In the study on melanogenic protein expression, 70% ethanol extracts of Scolopendra subspinipes mutilans blocked glycosylation of tyrosinase. Therefore this result suggests that 70% ethanol extracts could be developed as skin whitening agents.

• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.1005-1014
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• 2019

The purpose of this study is to evaluate the usefulness of coronary computed tomography angiography of coronary artery disease for the purpose fo health screening according to gender and age. In addition the association between hematological factors (Glucose, total cholesterol, visceral fat, body mass index, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL)) and coronary artery disease is investigated. A retrospective analysis of coronary computed tomography angiography with 299 subjects showed that the detection rate of coronary artery disease was higher in men over 50 years of age and it was statistically significant. In particular, the prevalence rate of men (37.9%) was about 2 times higher than that of women (17.0%). Glucose and HDL as hematological factors associated with coronary artery disease were statistically significant. The prevention and management of coronary artery disease seems to require the control of glucose and high density lipoprotein (HDL). Although it is not statistically significant with other hematological factors, the need for management of coronary artery disease was identified. the coronary computed tomography angiography of coronary artery has higher radiation doses than other CT scans. Therefore, for the purpose of screening, coronary computed tomography angiography should be considered in consideration of the sex and age of the examinee, and detection of coronary artery disease through other non-invasive tests should be prioritized over coronary computed tomography angiography.

• Research in Plant Disease
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• v.18 no.3
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• pp.225-230
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• 2012

Bacteriophages of Pectobacterium carotovorum subsp. carotovorum which causes soft rot on diverse vegetables had been isolated from 6 major Chinese cabbage cultivation areas in Korea. In order to isolate bacteriophages, total 15 different strains of P. carotovorum subsp. carotovorum isolated from nation-wide of Korea had been used as a host. When we tested 30 different soil samples individually from Pyeongchang and Taebaek with 15 different strains as a host, Taebek soil samples showed bacteriophage plaques with almost all different indicator strains but Pyeongchang soil samples showed plaques only with P. carotovorum subsp. carotovorum Pcc2 and Pcc3 strains. Especially, P. carotovorum subsp. carotovorum Pcc3 strain was able to produce plaques with almost all soil samples. Thus, this strain can be used as an indicator strain for P. carotovorum subsp. carotovorum bacteriophage screening. Electron microscope observation revealed P. carotovorum subsp. carotovorum bacteriophages isolated in Korea were belonged to three different families, Myoviridae, Siphoviridae and Podoviridae in order Caudovirales.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.669-671
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• 2006

Purpose: Congenital insensitivity to pain with anhidrosis(CIPA) is a rare form of autosomal recessive peripheral sensory neuropathy. Patients with CIPA show loss of pain sensation, which leads to corneal ulcers and opacities, self-mutilation of the tongue and fingertips, as well as fractures with subsequent joint deformities and chronic osteomyelitis. The purpose of this report is to highlight the fact that pressure sores also are a potential complication of CIPA. Methods: This case report describes a patient presenting with pressure sores resulting from CIPA. A 5-year-old boy was referred to our department for the treatment of a $5{\times}5cm$ sacral pressure sore as a result of a hip spica cast applied for the treatment of a left hip joint dislocation. He had a history suggesting CIPA such as multiple bony fractures, mental retardation, recurrent hyperpyrexia, anhidrosis, and clubbing fingers due to oral mutilation. A microscopic examination of the sural nerve showed mainly large myelinated fibers, a few small myelinated fibers and an almost complete loss of unmyelinated fibers. After wound preparation for two weeks, the exposed bone was covered with two local advancement flaps. Results: Two weeks later, complete wound healing was achieved. A 16-month follow-up showed no recurrence. However, the patient presented with a new pressure sore on the left knee due to orthosis for the treatment of the left hip joint dislocation. Conclusion: The early diagnosis of CIPA and special care of pressure sores are important for preventing and treating pressure sores resulting from CIPA.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.533-538
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• 2008

Purpose: Sensory changes in the upper limb are complications of a mastectomy with immediate breast reconstruction with the treatment of breast cancer. The purpose of this study is to clarify whether immediate breast reconstruction worsens the sensory changes. Methods: From March 2004 to December 2005, 20 patients who had a mastectomy with immediate breast reconstruction(reconstruction group) were compared with 23 patients who had a mastectomy alone(control group). All patients had stage I or II breast cancer. The sensory changes were assessed in a blind manner by one examiner that used light touch sensation, static two-point discrimination, pain, vibration, hot and cold temperature perception. The sensory changes were identified along the sensory dermatome for diagnosing the damaged nerves. The following factors and their relationship with the sensory changes were analyzed : age, complications, and the mastectomy method. Results: There was no statistical difference in the static two-point discrimination, pain, vibration, hot and cold temperature perception between the two groups. However, the ability to recognize light touch was significantly better(p=0.045) in the reconstruction group than in the control group. The main site of sensory change was the proximal and medial portion of the upper limb in both groups. At these sites, the mean value of Semmes-Weinstein monofilament was $1.01g/mm^2$(reconstruction group 0.82, control group 1.17) and 2-point discrimination was 51.74(converted to perfect score of 100; reconstruction group 42.50, control group 59.78). The total rate of early complications was found to be significantly lower(p=0.006) in the reconstruction group than in the control group. Conclusion: These findings suggest that an immediate breast reconstructive procedure following a mastectomy is as safe as or safer than a mastectomy alone with respect to postoperative sensory changes of the ipsilateral upper limb.