• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2803-2811
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• 2020

With the aging of nuclear reactors, embrittlement of the reactor pressure vessel (RPV) steel, as a consequence of routine operations, is highly probable. To ensure operational integrity and safety, prediction and mitigation of compromising damage, brought on by pressurized thermal shock (PTS) following an emergency procedure, is of utmost importance. Computational fluid dynamics (CFD) codes can be employed to predict these events and have therefore been an acceptable method for such assessments. In this paper, CFD simulations of a density driven ECC state in the ROCOM facility are analyzed. Obtained numerical results are validated with the experimental measurements. Considerable attention is attributed to the boundary conditions and their influence, specifically outlet definitions, in order to determine and adequately replicate the non-active pumps in the facility. Consequent analyses focused on initial conditions as well as on the temporal discretization and inner iterations. Disparities due to different turbulent modelling approaches are investigated for standard RANS models. Based on observed trends for different cases, a definitive simulation setup has been established, results of which have been ultimately compared to the measurements.

• Korean Journal of Plant Resources
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• v.35 no.6
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• pp.713-719
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• 2022

Platycodon grandiflorum and Glycyrrhiza uralensis contain several bioactive compounds, such as saponin, oleanolic acid, and flavone. P. grandiflorum and G. uralensis have traditionally been used to treat disorders related to blood pressure, diabetes, and counteracting poison, and they have antinociceptive and antiinflammatory properties. However, the validity of complex saponin's vasodilatory effect has not been scientifically investigated. Therefore, this study explores the vasodilatory effect of complex saponin extracted from P. grandiflorum and G. uralensis mixture extract on rabbit carotid arteries. To this end, arterial rings with intact or damaged endothelium were used in an organ bath experiment and contracted by endothelin. Complex saponins, the major active constituents of P. grandiflorum and G. uralensis mixture extract, exhibited a moderate vasodilatory effect on the rabbit's basilar arteries. Therefore, treatment with complex saponin extracted from P. grandiflorum and G. uralensis mixture extract may selectively accelerate cerebral blood flow through basilar arterial dilation. Overall, the findings suggest that the extracted complex saponins can serve as vasodilator sources.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.119-130
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• 1996

We review the factors which regulate the depth and composition of the human airway surface liquid (ASL). These include secretion from airway submucosal glands, ion and fluid transport across the surface epithelium, goblet cell discharge, surface tension and transepithelial gradients in osmotic and hydrostatic pressure. We describe recent experiments in which we have used low temperature scanning electron microscopy of rapidly frozen specimens to detect changes in depth of ASL in response to submucosal gland stimulation. We also present preliminary data in which X-ray microanalysis of frozen specimens has been used to determine the elemental composition of ASL.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.3
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• pp.231-245
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• 2023

In the cosmetics industry, it is important to develop new materials for functional cosmetics such as whitening, wrinkles, anti-oxidation, and anti-aging, as well as technology to increase absorption when applied to the skin. Therefore, in this study, we tried to optimize the nanoemulsion formulation by utilizing response surface methodology (RSM), an experimental design method. A nanoemulsion was prepared by a high-pressure emulsification method using Glabridin as an active ingredient, and finally, the optimized skin absorption rate of the nanoemulsion was evaluated. Nanoemulsions were prepared by varying the surfactant content, cholesterol content, oil content, polyol content, high-pressure homogenization pressure, and cycling number of high-pressure homogenization as RSM factors. Among them, surfactant content, oil content, high-pressure homogenization pressure, and cycling number of high-pressure homogenization, which are factors that have the greatest influence on particle size, were used as independent variables, and particle size and skin absorption rate of nanoemulsion were used as response variables. A total of 29 experiments were conducted at random, including 5 repetitions of the center point, and the particle size and skin absorption of the prepared nanoemulsion were measured. Based on the results, the formulation with the minimum particle size and maximum skin absorption was optimized, and the surfactant content of 5.0 wt%, oil content of 2.0 wt%, high-pressure homogenization pressure of 1,000 bar, and the cycling number of high-pressure homogenization of 4 pass were derived as the optimal conditions. As the physical properties of the nanoemulsion prepared under optimal conditions, the particle size was 111.6 ± 0.2 nm, the PDI was 0.247 ± 0.014, and the zeta potential was -56.7 ± 1.2 mV. The skin absorption rate of the nanoemulsion was compared with emulsion as a control. As a result of the nanoemulsion and general emulsion skin absorption test, the cumulative absorption of the nanoemulsion was 79.53 ± 0.23%, and the cumulative absorption of the emulsion as a control was 66.54 ± 1.45% after 24 h, which was 13% higher than the emulsion.

• The Korean Journal of Pharmacology
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• v.15 no.1_2 s.25
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• pp.29-37
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• 1979

The tension-length relationships and reactivity of vascular smooth muscle in longitudinal strips from portal vein ana in helical strips from thoracic aorta and pulmonary artery of normotensive control and cadmium-hypertensive rabbits were studied in vitro. 1. The mean arterial pressures of non-poisoned control rabbits was $87.0{\pm}4.7 mmHg$. However, Cd-poisoned group revealed the significant increase in pressure by $109.04{\pm}2.8 mmHg$ (p<0.005). 2. By tension-length studies, strips from portal vein of Cd-poisoned group stretched a greater percent increase in length in response to an applied resting force from 0.25 to 5 g than did those from non-poisoned group. On the contrary, strips from thoracic aorta of Cd-poisoned group showed less compliant than those from control, i.e. the former underwent a less percent increase in length than the latter. Passive tension-length relations of pulmonary artery was unaffected by Cd-hypertension. 3. The force of contraction(active tension) was significantly lowered in strips from aorta of Cd-hypertensive group throughout the range of $0.5{\sim}2g$ passive tension. However, there was no significant difference in the development of active tension of portal vein or pulmonary artery of both groups. 4. The $K^+$-contraction in the portal vein, aorta and pulmonary artery of Cd-poisoned group made no difference in the active force from those of control group. 5. The force of contraction in the strips from aorta of Cd-poisoned group was significanty decreased compared to that of control. The results suggested that the alterations in vascular reactivity to contracting substances and in distensibility to passive tension were induced in the Cd-hypertensive rabbits.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.609-622
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• 2019

When the surfactant is dissolved in an aqueous solution, it forms aggregate called micelles (<20 nm) in the solution, and micelles can form the solubilized formulation by supporting the active ingredient therein. Swollen micelles are formulations capable of carrying larger amounts of active ingredient than conventional solubilized formulations at 50~100 nm. Unlike liposomes or nanoemulsions, which require a separate process such as high pressure emulsification, Swollen micelle is a more efficient method of solubilization and particle formation from a productive point of view. In this study, stabilization experiments on swollen micelle formulations were carried out using poloxamer 407, and then optimized formulation experiments for tocopheryl acetate components were performed using Response Surface Methodology (RSM). Tocopheryl acetate, a surfactant that affects solubilization and an active substance, were set as a factor and the correlation between them was confirmed. As the evaluation method, stability and particle size distribution and size were confirmed by temperature and time, and the structure and shape of the swollen micelle carrying the active ingredient were confirmed by FIB. These results show that poloxamer 407 0.500%, octyldodeceth-16 0.387% and tocopheryl acetate 0.945% are the most optimized prescriptions for swollen micelle stabilized with tocopheryl acetate.

• Journal of Acupuncture Research
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• v.24 no.1
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• pp.13-28
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• 2007

Objectives : Clinical character of chronic tension-type headache is bilateral, moderate intensity, persistent and chronic, repeating disease and CTTH is a common prevalent disease, but pathophysiology and likely mechanism remain unclear. It impedes subjective quality of life. The purpose of this research is to examine the effect of sa-am acupuncture method for chronic tension-type headache. Methods : In this randomized, single blind, placebo-controlled study, we compared active acupuncture with sham acupuncture for the treatment of chronic tension-type headache. Volunteers who satisfied the requirements were enrolled in study. Evaluation of chronic tension-type headache was measured by VAS and Headache Disability Inventory(HDI), Six point Linkert Scale before and after treatments. Results : 26 subjects finished study. There were not difference between two groups on age, sex, weight, height, blood pressure, pulse, respiratory rate, Byeonjeung, sunrise of treatment. In change of VAS, there were not difference between two groups on before treatment. Before treatment per visit, VAS of 6th and 7th visit were significantly decreased in active acupuncture(each p=0.039, p=0.008) and were not decreased in sham acupuncture. In change of VAS on a withdrawing needling after treatment, VAS of 1st, 2nd, 6th and 7th visit were significantly decreased in active acupuncture (each p=0.001, 0.038, 0.035, 0.008) and VAS of 2nd, 4th and 5th, 6th visit were significantly decreased in sham acupuncture(each p=0.033, 0.032, 0.035, 0.031). In change of VAS on 2hrs after treatment, VAS of 4th and 5th, 6th visit were significantly decreased in active acupuncture(each p=0.014, 0.023, 0.027) and 5th visit were significantly decreased in sham acupuncture(each p=0.004, 0.009). In change of VAS on 4hrs after treatment, VAS of 4th and 5th, 6th visit were significantly decreased in active acupuncture(each p=0.018, 0.011, 0.015) and 5th, 6th visit were significantly decreased in sham acupuncture(each p=0.020, 0.015). In change of VAS on the next day after treatment, VAS of 3th and 4th and 5th, 6th visit were significantly decreased in active acupuncture(each p=0.032, 0.011, 0.005, 0.012) and 4th, 5th visit were significantly decreased in sham acupuncture(each p=0.001, 0.012). In change of VAS according to a current time(before treatment, after a withdrawing needling, 2hrs, 4hrs, the next day), total score of VAS was decreased more active acupuncture group than sham acupuncture group, but there were no statistical significance compared with sham acupuncture group. In change of HDI score, after treatment was decreased than before treatment in two group, but there were no statistical significance compared with two group. In change of Six point Linkert scale score, after treatment was decreased than before treatment in two group on 6th, 7th visit(active acupuncture 6th 7th each p=0.002, 0.003, sham acupuncture 6th 7th each 0.003, 0.009), but there were no statistical significance compared with tow group. Conclusion : Sa-am acupuncture treatment is effective to improve the symptoms and quality of life in patients with chronic tension-type headache.

• The Journal of Korean Society for School & Community Health Education
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• v.4
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• pp.21-41
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• 2003

The purposes of this study were to ; first, investigate High School Teachers health promotion behavior types; second, explore the effects High School Teachers perceived benefits and perceived barriers have on their health promotion behavior ; third, suggest a desirable course that will increase teachers health. To this end, this researcher conducted a survey on health promotion behavior, perceived benefits, and perceived barriers to 329 High School teachers working in Goyang-si, Gyonggi-do. The results of the survey are as follows: Health Promotion Behavior A closer look at high school teachers health promotion behavior shows that male teachers, compared with female teachers, more actively promote their health. However, female teachers are more aware of their personal hygiene and disease risks. Older teachers, rather than younger teachers, are more willing to promote their health through better eating habits and more frequent exercise. A comparison between married and single teachers revealed that married teachers promote their health through better eating habits, and single teachers receive less stress and are better at managing their stress. Teachers working in technical high schools are better at managing their stress and personal hygiene than academic high schools teachers. Teachers working after 8 o'clock show better health promotion behavior through proper eating habits, stress management, regular exercise, disease prevention: however, teachers working before 7:30 are poor at managing their stress. Teachers not teaching supplementary lessons and not supervising night self-study are better at managing their stress, exercise schedule, and disease prevention than teachers who are. Perceived Benefits, Perceived Barriers, and Health Promotion Behavior A Comparison between male and female teachers shows that female teachers firmly believe improved eating habits and regular exercises would greatly enhance their health. However, female teachers felt more discomfort in their working environment and in utilizing medical institutes. Teachers in the 20s and 40s perceived health benefits through regular lifestyle and exercise. Teachers with less experience feel more pressure from their work environment. Teachers below their 30s feel more dissatisfaction towards using medical facilities. Teachers working in Technical High Schools are more aware of promoting their health through regular health checkups, exercise, and lifestyle ; however, teachers from Academic High Schools feel more pressure from their work environment. Teachers not performing supplementary lessons and supervising night self-study sessions are more willing to go through regular health checkups than those performing them. Also, teachers with supplementary lessons and night self-study supervisions claimed lack of leisure time, pressure from work environment, and inconvenience in using medical facilities a deterrent to promoting their health behavior. The Relationship between Health Promotion Behavior, Perceived Benefits, and Perceived Barriers The correlation ratio between Health Promotion Behavior and Perceived Benefits shows a positive relationship. The results show that High School teachers believed regular health checkups are necessary in maintaining their health. This research shows that teachers consider the following factors important in the order shown ; regular lifestyle and exercise, prevention of geriatric diseases, improving ones eating habits. In short, teachers who are more aware of the importance of regular health checkups are also more aware of the importance of promoting their health. The correlation ratio between Health Promotion Behavior and Perceived Barriers shows negative relationship. High School Teachers believe that lack of leisure activity, pressure from work environment, familys financial burden, fear of diseases, inconvenience in using medical facilities are a deterrent in promoting their health behavior. In other words, teachers with less leisure time and negative pressures from their work environment were less active in promoting their health behavior. This study shows that High School teachers will be able to promote their health behavior by maintaining regular health checkups, lifestyle, exercise, and preventing geriatric diseases. However, teachers believed that insufficient leisure time and negative pressure from their work environment acted as a deterrent to maintaining their health behavior. Most High School teachers believe they are at present healthy, and they were actively engaged in Preventative Health Promotion. The result of this study demonstrates that External factors have a large impact on teachers, which in turn acts negatively on their Health Promotion Behavior. In order to guarantee teachers health promotion behavior, systematic health checkups and increased leisure time, improvement in their work environment are necessary. Teachers also need to take a more active interest in their health.

• Research in Community and Public Health Nursing
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• v.11 no.1
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• pp.231-244
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• 2000

Parish nursing is a community health nursing role developed in 1983 by Lutheran Chaplain Granger Westberg. An increasing emphasis on holistic care, personal responsibility for a healthy lifestyle, and changes in healthcare delivery systems have undoubtedly facilitated the establishment of an innovative nursing role in the community. Parish nurses are functioning in a variety of church congregations of various denominations. The parish nurse is a educator, a personal health counselor, a coordinator of volunteers. The parish nurses helps people relate to the complexed medical care system and assists people to integrate faith and health. The purpose of this study is to investigate what the korean parishioners want in parish nursing and what type of role expectation from parish nurse. The subjects were 1138 parishioners of 23 churches of various denominations in nationwide Korea. Data were collected by self-reported question naires from Feb 4 to June 25. 1999. The data were analyzed by using percentage. frequency. $x^2-test$. multiple Response set with SPSS program. The results are as follows: 1. Desired parish nursing contents by parish nurses are: psychological counselling(23.4%) out of private counselling. stress management(21.1 %) out of private health education. Emergency care(14.1%) out of group health education. Blood Pressure check-ups (19.0%) out of Health check ups. home visiting(44.9%) out of patient visiting method. B T. pulse, respiration and blood pressure check(15.0%) in Care to serve in home visiting. spiritual preparation to accept the death(41.7%) in hospice care, advices to choice of medical treatment using guide(50.1%) in introducing and guiding of health care facilities, pray(21.7%) in spiritual care' faith support. 2. Desired Health Teaching Content According to Period of Clients by Parish Nurse are: Vaccination(22.5%) in infant and toddler health management. sexual education(25.3%) in adolescent health management. prenatal care (29.5%) in pregnant health management. osteoporosis prevention and management (22.4%) in Middle aged health management. dementia prevention and management(25.5%) in elderly health management. 3. The expectant role from parish nurse is spiritual care faith support(14.1%). patient visiting care(13.2%), hospice care(12.9%), private counseling(12.8%), health check ups (11.1 %), volunteer organization and training out of believer(11.0%), private health education (9.3%), group health education (8.3%). 4. In Necessity of Performing Parish Nursing according to Region, Most(over 95%) responded that nursing program is needed. so there is no significance between regions. In Performing Parish Nursing in their church, Most(92.2%) responded they want to perform program. 5. In case of performing parish nursing, 52% out of the subjects responded they want to participated in parish nursing volunteer's activity, for example. to be in active to be a companion to chat(42.1%), necessity support (25.3%), donation support(25.0%), exercise support(18.2%), vehicles support (9.9%). As a result. in holistic care and spiritual care, the need of parish nursing and the role expectation from parish nurse are very high among korean believers. Therefore, I suggest parish nursing centering around Taegu and Kyungbuk province should be extended to nationwide. For extending parish nursing program. more active advertisement and research is needed. After performing parish nursing program through out the country, further comparative research between regions should be practiced and Korean parish nursing program will be developed and activated.

• The korean journal of orthodontics
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• v.37 no.5
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• pp.351-363
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• 2007

The aim of this study was to evaluate pulp and periodontal changes following rapid tooth retraction by periodontal distraction after bone undermining surgery in young adult dogs. Methods: Alter extraction of second premolars, the interseptal bone mesial to the upper 3rd premolar was undermined. After activating the distraction appliance at 0.5 mm/day for six days, the dogs were sacrificed at 0, 1, 3, 5, 7, and 9 weeks during the consolidation period. Tissue changes of periodontium and pulp were evaluated radiologically, histologically, and immunohistochemically. Results: Digital subtraction radiography showed active bone formation in the stretched periodontal ligament from 0 - 4 weeks. Resorption of the alveolar bone, appearance of osteoclasts, and infiltration of inflammatory cells were observed just after the activation period at the pressure side, and distinctive bone formation was seen in the tension side of the periodontal ligament from 1 week. New bone formation was active at 1 - 3 weeks. The expression of calcitonin gene-related peptide in the experimental group was increased at the alveolar bone and pulp, and periodontal ligament at the pressure side from 0 - 1 week, and it decreased after 5 weeks to become similar to that of the control group. Conclusions: The results showed that rapid tooth movement using periodontal distraction can be new form of orthodontic tooth movement for accelerating normal bone formation.