• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.57-64
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• 2013

Cells can resist and even recover from stress induced by acute hypoxia, whereas chronic hypoxia often leads to irreversible damage and eventually death. Although little is known about the response(s) to acute hypoxia in neuronal cells, alterations in ion channel activity could be preferential. This study aimed to elucidate which channel type is involved in the response to acute hypoxia in rat pheochromocytomal (PC12) cells as a neuronal cell model. Using perfusing solution saturated with 95% $N_2$ and 5% $CO_2$, induction of cell hypoxia was confirmed based on increased intracellular $Ca^{2+}$ with diminished oxygen content in the perfusate. During acute hypoxia, one channel type with a conductance of about 30 pS (2.5 pA at -80 mV) was activated within the first 2~3 min following onset of hypoxia and was long-lived for more than 300 ms with high open probability ($P_o$, up to 0.8). This channel was permeable to $Na^+$ ions, but not to $K^+$, $Ca^+$, and $Cl^-$ ions, and was sensitively blocked by amiloride (200 nM). These characteristics and behaviors were quite similar to those of epithelial sodium channel (ENaC). RT-PCR and Western blot analyses confirmed that ENaC channel was endogenously expressed in PC12 cells. Taken together, a 30-pS ENaC-like channel was activated in response to acute hypoxia in PC12 cells. This is the first evidence of an acute hypoxia-activated $Na^+$ channel that can contribute to depolarization of the cell.

• Journal of Environmental Health Sciences
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• v.47 no.5
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• pp.379-383
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• 2021

This paper discussed environmental health policies for the past and coming decade by reviewing the First Comprehensive Environmental Health Plan (2011~2020) and introducing the Second Comprehensive Environmental Health Plan (2021~2030). The major achievement of the First Comprehensive Environmental Health Plan was the establishment of receptor-oriented environmental health policies. However, the main limitations were insufficient policy support for relief and/or recovery from environmental pollution damage and low public awareness of environmental health policies. The Second Comprehensive Environmental Health Plan presents the following major policy tasks: establish an omnidirectional environment health investigation and monitoring system, provide customized environmental health services, improve the environmental health damage relief and recovery system, and promote regional environmental health policies. The Second Plan has a clear distinction from the First Plan in that it expands the field of environmental health from the prevention and management of environmental risk factors to proactive damage response and recovery, which will effectively contribute to alleviating the burden of environmental disease.

• Journal of Korean Academy of Nursing
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• v.34 no.2
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• pp.213-224
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• 2004

Purpose: This study was aimed to evaluate the effect of progressive muscle relaxation training using biofeedback on perceived stress, stress response, immune response and climacteric symptoms, Method: This was a crossover, pre-post test design, The study subjects are 36 middle-aged women who were selected at 2 public health centers, The independent variable was Biofeedback training for 4 weeks, twice a week and home training for 4 weeks, Dependent variables were perceived stress, stress response, immune response, and climacteric symptoms measured with Hildtch's scale (1996), Result: Progressive muscle relaxation training using biofeedback was not effective in reducing perceived stress, but it was shown to be effective in reducing physiological stress responses such as pulse rate and EMG, Though blood pressure and skin conductance were repeatedly down, and skin temperature slowly increased, there were no statistically significant differences. Progressive muscle relaxation training using biofeedback was not effective in reducing serum cortisol, enhancing immune responses, or decreasing climacteric symptoms. Conclusion: The findings point to a pressing need for further, well-controlled and designed research with consideration in selection of subjects and instruments, frequency of measurements, the sampling method, and intervention modalities.

• Journal of Korean Academy of Nursing
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• v.8 no.2
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• pp.89-102
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• 1978

Owing to the development of modern science, prolonging man's life, the sudden increase of population and betterment of the standard of living has increased health needs. In order to fulfill these health needs, more active plans for developing health should be made. Health education is one of the methods at hand that can improve the health behavior of the community and the individual through the contact of individuals with their groups. Proper understanding of the characteristics of the sampled group and participation of individuals within the community for the development of their health plan are needed for efficient health education. This study was attempted for the purpose of presenting some data helpful for pre-paring the fundamentals of a health education plan that can improve personal health maintenance practice of a community through efficient health education by investigating the relationship between the response of subjects to personal health maintenance practice and selected decisive factors in personal health maintenance practice. The subjects for this study were a systematic sample of 120 housewives selected from 600 housewives from B Zone Apt. Younhi-3-Dong in Seoul. Data was collected for 4 days from May 16th to May 19th, 1578 through personal interviews with questionnaires by well trained interviewers. Percentage, t-test and stepwise multiple regression analysis by use of EDPS were employed for statistical analysis. Results of this study can be summarized : 1. General characteristics of subjects Subjects over 20 and below 40 years of age formed 62.5% of the toed and the rest were subjects of 40 years and upward. 76.7% of the subjects have less than 4 children. 51.3% of the subjects had completed at least the senior high school course. 2. The response of subjects to personal health maintenance practice. Ratios of personal health maintenance practice to the maximum score for each category are as follows; 84.1% in the category of population and family planning, which was the highest ratio; 82.4% in the prevention of accidents; 68.0% in control of communicable disease; 67.8% in personal health care and habits of daily life, 64.3% in mental health and 52.5% in control of parasites, which was the lowest. 3. The response of subjects to selected decisive factors. in personal health maintenance practice. The arithmetic mean of the score for each decisive factor was as follows: the mutual relation between family members marked 18.33, which is under 73,3% of the maximum score; the degree of interest in health marked 34.48, 70.0% of the maximum score: the degree of utilization and demand for health care facilities marked 25.79 or 64.5% of the maximum score and health maintenance of the family marked 11.58, 43.6% of the maximum score. 4. The relationship between personal health maintenance practice and general characteristics of subjects. 1) There was a significant difference in the numbers of children. (t = 1.83, d.f. =117, p< 0.1) 2) There was a significant difference in the contact rates with mass-media, (t = 5.02, d.f. = 118, p< 0,05) 5. The multiple correlation between personal health maintenance practice and their selected decisive factors. 1) The factor“the degree of interest in health”could account for personal health maintenance practice in 43.6% of the sample. (R = 0.6602, R²= 0,4359, F = 91.1678, p< 0.001) 2) When the factor,“health maintenance of family”is added to this, it accounts for 51.2% of personal health maintenance practice. (R = 0.7158, R²= 0.5124, F = 61.4653, p< 0.001) 3) When the factor,“mutual relations between family members”is also included, it accounts for 53.7% of personal health maintenance practice. (R = 0.7324, R²= 0.5365, F = 44.7509, p< 0.001) 4) When the factor, “the degree of utilization and demand for health care facilities”is included, it accounts for 55.1% of personal health maintenance practice. (R = 0.7421, R²= 0.5507, F = 35.2430, p< 0.001).

• International Journal of High-Rise Buildings
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• v.1 no.1
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• pp.37-51
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• 2012

New generation of tall and complex buildings systems are now introduced that are reflective of the latest development in materials, design, sustainability, construction, and IT technologies. While the complexity in design is being overcome by the availability and advances in structural analysis tools and readily advanced software, the design of these buildings are still reliant on minimum code requirements that yet to be validated in full scale. The involvement of the author in the design and construction planning of Burj Khalifa since its inception until its completion prompted the author to conceptually develop an extensive survey and real-time structural health monitoring program to validate all the fundamental assumptions mad for the design and construction planning of the tower. The Burj Khalifa Project is the tallest structure ever built by man; the tower is 828 meters tall and comprises of 162 floors above grade and 3 basement levels. Early integration of aerodynamic shaping and wind engineering played a major role in the architectural massing and design of this multi-use tower, where mitigating and taming the dynamic wind effects was one of the most important design criteria established at the onset of the project design. Understanding the structural and foundation system behaviors of the tower are the key fundamental drivers for the development and execution of a state-of-the-art survey and structural health monitoring (SHM) programs. Therefore, the focus of this paper is to discuss the execution of the survey and real-time structural health monitoring programs to confirm the structural behavioral response of the tower during construction stage and during its service life; the monitoring programs included 1) monitoring the tower's foundation system, 2) monitoring the foundation settlement, 3) measuring the strains of the tower vertical elements, 4) measuring the wall and column vertical shortening due to elastic, shrinkage and creep effects, 5) measuring the lateral displacement of the tower under its own gravity loads (including asymmetrical effects) resulting from immediate elastic and long term creep effects, 6) measuring the building lateral movements and dynamic characteristic in real time during construction, 7) measuring the building displacements, accelerations, dynamic characteristics, and structural behavior in real time under building permanent conditions, 8) and monitoring the Pinnacle dynamic behavior and fatigue characteristics. This extensive SHM program has resulted in extensive insight into the structural response of the tower, allowed control the construction process, allowed for the evaluation of the structural response in effective and immediate manner and it allowed for immediate correlation between the measured and the predicted behavior. The survey and SHM programs developed for Burj Khalifa will with no doubt pioneer the use of new survey techniques and the execution of new SHM program concepts as part of the fundamental design of building structures. Moreover, this survey and SHM programs will be benchmarked as a model for the development of future generation of SHM programs for all critical and essential facilities, however, but with much improved devices and technologies, which are now being considered by the author for another tall and complex building development, that is presently under construction.

• Radiation Oncology Journal
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• v.30 no.3
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• pp.140-145
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• 2012

Purpose: Combined chemoradiotherapy is standard management for locally advanced non-small cell lung cancer (LA-NSCLC), but standard treatment for elderly patients with LA-NSCLC has not been confirmed yet. We evaluated the feasibility and efficacy of concurrent chemoradiotherapy (CCRT) for elderly patients with LA-NSCLC. Materials and Methods: Among patients older than 65 years with LA-NSCLC, 36 patients, who underwent CCRT were retrospectively analyzed. Chemotherapy was administered 3-5 times with 4 weeks interval during radiotherapy. Thoracic radiotherapy was delivered to the primary mass and regional lymph nodes. Total dose of 54-59.4 Gy (median, 59.4 Gy) in daily 1.8 Gy fractions and 5 fractions per week. Results: Regarding the response to treatment, complete response, partial response, and no response were shown in 16.7%, 66.7%, and 13.9%, respectively. The 1- and 2-year overall survival (OS) rates were 58.2% and 31.2%, respectively, and the median survival was 15 months. The 1- and 2-year progression-free survivals (PFS) were 41.2% and 19.5%, respectively, and the median PFS was 10 months. Regarding to the toxicity developed after CCRT, pneumonitis and esophagitis with grade 3 or higher were observed in 13.9% (5 patients) and 11.1% (4 patients), respectively. Treatment-related death was not observed. Conclusion: The treatment-related toxicity as esophagitis and pneumonitis were noticeably lower when was compared with the previously reported results, and the survival rate was higher than radiotherapy alone. The results indicate that CCRT is an effective in terms of survival and treatment related toxicity for elderly patients over 65 years old with LA-NSCLC.

• Journal of Preventive Medicine and Public Health
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• v.28 no.4 s.51
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• pp.795-807
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• 1995

This study was carried out from 1993 to 1994 in the small industries in Incheon. The objectives of this study was in order to estimate the quitting rate, to identify its relating factors and to propose effective quitting management policy in the small industries. The results were as follows ; 1. The quitting rate of 266 study workers was 42.1%(112 workers). 2. Age, working duration, position, marrital status were significant difference between the quitting group and the non - quitting group. In the quitting group, mean age was young, working duration was short, general employees and unmarried workers were many compared with the non - quitting group. 3. In the industry characteristics, total assets, total assets, sales per person, establishment duration and occupational health and safely status were significant difference between the quitting group and the non - quitting group. In the quitting group, total assets, total sales and sales per person were little, establishment duration of company was short and occupational health and safety status were poor compared with the non - quitting group. 4. In the quitting group, worker's response to employer's disposal about health and safety was more passive and the relation to employer with employee was significantly poor compared with the non - quitting group. 5. Multiple logistic regression analysis of quitting against family income per person, working duration, relation to employer with employee, occupational health and safety status in industry, worker's response to employer's disposal about health and safety and sales per person was done. Working duration, occupational health and safety status, worker's response to employer'1 disposal about health and safety were significant explainatory variables for quitting. Above results showed that the quitting rate was high and it was significant difference between the quitting group and non : quitting group according to characteristics of workers and of industries. Especially, it suggested that working duration, occupational health and safety status and worker's response to employer's disposal about health and safety were significant quitting factor. Therefore, it should be reflected in the quitting management and the policy of steady employment.

• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.16-22
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• 1995

This study was designed to investigate the antibody production to sheep red blood cells(SRBC) and proliferation of mitogen-stimulated spleen cells in Balb/c mice which received cadmium chloride. The mice were divided into three independent groups which were one control and two experimental groups by the cadmium treatment or not. No specific treatment was done for the control group. One of two experimental groups, which is called 'pre-treatment group' in this paper, was subcutaneously injected with low dose of cadmium chloride(0.5 mg/kg/day) for 5 consecutive days before the primary SRBC immunization. The other called 'non-pretreatment group' was only pretreated with normal saline. Both experimental groups were intraperitoneally injected with high dose of cadmium chloride(5 mg/kg) 8 hours before the primary immunization. Mice were intraperitoneally immunized twice with 2% SRBC suspension containing $10^8$ cells. The results obtained were as follows, 1. The PFG responses to SRBC were significantly increased in two experimental groups, cadmium pretreatment and non-pretreatment compared with that of control group(p<0.05). 2. The total antibody titers to SRBC in cadmium treated groups were similar to that of control group, but titers of IgG antibody were significantly elevated(p<0.01). 3. The proliferation response of spleen lymphocytes to various mitogens was suppressed in proportion to the concentration of cadmium and the degree of cadmium accumulation in liver was increased in the cadmium treated groups. These results suggest that cadmium chloride could affect on mouse immune response, especially its cell mediated immune response could be decreased while its humoral immune response could be increased, which may not be influenced by the administration methods or pretreatment of cadmium to mouse.

• Structural Monitoring and Maintenance
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• v.1 no.4
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• pp.371-392
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• 2014

Long-span cable-supported bridges are flexible structures vulnerable to unsymmetric loadings such as railway traffic and strong wind. The torsional dynamic response of long-span cable-supported bridges under running trains and/or strong winds may deform the railway track laid on the bridge deck and affect the running safety of trains and the comfort of passengers, and even lead the bridge to collapse. Therefore, it is eager to figure out the torsional dynamic response of long-span cable-supported bridges under running trains and/or strong winds. The Tsing Ma Bridge (TMB) in Hong Kong is a suspension bridge with a main span of 1,377 m, and is currently the world's longest suspension bridge carrying both road and rail traffic. Moreover, this bridge is located in one of the most active typhoon-prone regions in the world. A wind and structural health monitoring system (WASHMS) was installed on the TMB in 1997, and after 17 years of successful operation it is still working well as desired. Making use of one-year monitoring data acquired by the WASHMS, the torsional dynamic responses of the bridge deck under rail traffic and strong winds are analyzed. The monitoring results demonstrate that the differences of vertical displacement at the opposite edges and the corresponding rotations of the bridge deck are less than 60 mm and $0.1^{\circ}$ respectively under weak winds, and less than 300 mm and $0.6^{\circ}$ respectively under typhoons, implying that the torsional dynamic response of the bridge deck under rail traffic and wind loading is not significant due to the rational design.

• Journal of muscle and joint health
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• v.24 no.3
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• pp.217-226
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• 2017

Purpose: The aim of this study was to identify the effects of Tai Chi training program on physical fitness, stress response and ego-resiliency in nursing students. Methods: 28 nursing students of D metropolitan city participated in non-equivalent control group pre- and post-test group test in quasi experimental design with written consent. Fourteen participants in the control group who did usual activities and 14 experimental participants who promised to participate 24 Tai Chi training sessions for 12 weeks. Both groups completed pre- and post-test measurement for physical fitness, a questionnaire regarding their stress response and ego-resiliency. Each 60-minute Tai Chi session was consisted of 5-minute warm up, 10-minute meditation, 40-minute Tai Chi, and 5-minute finishing exercise. Results: After 12 weeks, participants in the Tai Chi group reported significantly higher score in muscle endurance (t=3.77, p=.001), leg muscular strength (t=2.14, p=.042), and balance (t=2.12, p=.044) compared to the control group. The Tai Chi group recorded significantly lower score than the control group on stress response (t=2.75, p=.011). Conclusion: The findings highlight the importance of Tai Chi for a reduction in stress response and promotion in physical fitness in nursing students. Applying Tai Chi training to nursing program will help nursing students to have better academic performance.