• The Bulletin of The Korean Astronomical Society
• /
• v.40 no.1
• /
• pp.58.1-58.1
• /
• 2015

Gravitational-wave has been predicted by Einstein's general relativity in 1916, but its direct detection has failed to date despite of the persistent efforts in the last fifty years in the ground-based gravitational wave detectors. In the centennial year of the birth of general relativity, 'advanced LIGO', one of the most promising Earth-based gravitational wave detectors, plans to start commissioning for the successful discovery of gravitational waves. In addition, a pathfinder satellite of eLISA project, a space-based GW antenna by European Space Agency (ESA), will be launched in the mid of this year. In this talk, we review the current status of gravitational waves detection experiments and discuss its scientific impacts and the possibility of opening the new age of astronomy.

• Journal of Acupuncture Research
• /
• v.19 no.3
• /
• pp.126-137
• /
• 2002

Objective : There is accumulating data that cardiovascular diseases, including hypertension, cerebro-vascular accident, coronary heart disease, relate to atherosclerotic changes. Increased serum levels of lipids could play a role in these circumstances. the SDPTG(the second derivative of photoplethysmogram waveform) is noninvasive methods for evaluating the pulse wave and is correlated with age and other risk factors for atherosclerosis. Methods : To study the effects of serum lipid levels on the SDPTG in the middle-age adults, data on serum lipid levels and the SDPTG were collected in 80 healthy middle age with varying serum lipid concentrations. Biological vascular age was assessed using the SDPTG. the SDPTG consists of an a, b, c, and d wave in systole and an e wave in diastole; an SDPTG aging index(Al) was calculated as (b-c-d-e)/a. Results : Serum triglyceride, total cholesterol, total lipid, phospholipid, HDL cholesterol levels were respectively and significantly correlated with SDPTG Al. Serum lipid levels and blood pressure are age-dependent and the SDPTG is blood pressure-dependent. Restricting analysis to age and blood pressure yield strong positive correlations between serum triglyceride, total lipid levels and SDPTG Al, but no correlations between serum total cholesterol, phospholipid levels and SDPTG Al. Conclusion : The results of this study suggest that preventive acupuncture programs or herbal medications for reducing serum lipid, especially triglyceride, levels in middle-age should include a evaluation of biological vascular aging with the second derivative of photoplethysmogram waveform.

• Journal of Family Resource Management and Policy Review
• /
• v.19 no.4
• /
• pp.19-33
• /
• 2015

The purpose of this study is to explain. It also examines and compares factors influencing life satisfaction among the middle-aged at various income levels. The data source for this study was the third additional wave and the fourth wave of the Korean Retirement and Income The study sample consisted of 1,723 middle-aged (age 50-64) individuals. The data analysis methods included the chi-square test, ANOVA, and multiple regression analysis. The results were as follows. First, there was a positive relationship between old age preparation and life satisfaction. Second, it was found that old age preparations (physical, emotional, social, financial) and life satisfaction show meaningful relationships among the income levels. Third, old age preparation was found to have different meaningful impacts on life satisfaction among the income levels. The results of this study verify the degree of the relationship between old age preparation and life satisfaction and the different impact factors relating to old age preparation for life satisfaction among the income levels.

• Journal of Biomedical Engineering Research
• /
• v.28 no.4
• /
• pp.530-538
• /
• 2007

Magnetocardiography (MCG) is a device to measure the magnetic field from the heart. It is a noninvasive device and takes only few minutes to record magnetocardiogram from a subject. In this study, we compared the difference of MCG data recorded from 56 normal subjects in early twenties (28 males and 28 females, mean $age=21.0{\pm}1.6$ years) and 36 elderly subjects (20 males and 16 females, mean $age=61.9{\pm}6.9$ years) for the analysis of the age and gender difference. A total of 24 parameters used in the analysis were derived from QRS complex, R-wave, T-wave, and ST-T period. As a result, seven parameters including maximum current angle and map angle showed the significant difference (p<0.01 and p<0.05, respectively) between young males and young females. Significant difference (p<0.05) between elderly males and elderly females was found from a parameter, pole distance at T-wave peak. In the comparison of age difference, seven parameters regarding current moment, pole distance, and dynamics showed the significant difference between young and elderly males. Eight parameters also showed significant difference (p<0.05) between two younger and elderly female groups. Results showed that parameters regarding current moment, pole distance, and dynamics might be changed when people get older. In conclusion, gender and age difference should be considered when MCG data are analyzed for certain parameters.

• Pediatric Infection and Vaccine
• /
• v.31 no.1
• /
• pp.83-93
• /
• 2024

Purpose: Since the start of the coronavirus disease 2019 (COVID-19) pandemic, various variants of concern have emerged. We divided the representative COVID-19 mutation period into four waves and aimed to analyze the clinical and laboratory features of children with COVID-19 from pre-mutation wave to the middle of omicron wave. Methods: We retrospectively reviewed the medical records of hospitalized patients aged ≤19 years with laboratory confirmed COVID-19. Clinical and laboratory findings during pre-mutation (February 1st 2020 to September 30th 2020), alpha/beta (October 1st 2020 to May 31st 2021), delta (June 1st 2021 to October 31st 2021), and omicron (November 1st 2021 to May 31st 2022) waves were compared. Results: Among total 827 patients, 163 (19.7%) were asymptomatic, and the frequency of fever and cough was 320 (38.7%) and 399 (48.2%), respectively. The proportion of fever ≥38.5℃ was observed to be high during the omicron wave in the age group under 12 years. Lymphopenia was observed highly in the omicron wave in the age group under 12 years, and in the delta wave in the age group older than 12 years. Neutropenia was highly observed in the delta wave in the 0-4 years age group. Conclusions: There were distinct characteristics during all epidemic waves of COVID-19. Children with COVID-19 had more frequent persistent fever during delta wave and children during the omicron wave had a higher peak fever.

• Journal of Fashion Business
• /
• v.12 no.4
• /
• pp.28-45
• /
• 2008

The purpose of this study is to diagnose actual condition of preference of hair-styling, hair-styling techniques, management, grasping a consumer's consciousness, etc with women living in a city. The survey was gotten to a feminine customer who visited the ten of beauty-shops in shopping center. And statistical data about the actual condition of hair-styling preference realities, hair-styling method and style management was entered into the SPSS statistics analysis system. In brief, be as follows by the results of study. There showed significant difference that noted in hair-style information and basis alternative a beauty salon, there were able to know people whose age is from 20's to 40's got mainly an influence of public media very much and from 40's to 50's got mainly an influence of people around them. Basis alternative of a beauty salon showed significant difference to follow age categories. It appeared that introducing from people around them have a effect on the 20's and 30's, and 40's got an influence of convenience of traffic, and 50's got mainly the shortest distance. In an attitude toward a hair style, especially toward hair cut, a case to do hair cut was most a lot of in own selections, and its result was independent of age categories. The reason that wants to give a chance was most a lot of thinking without an age. Preference length of hair cut showed a significant difference according to age. In permanent section, own selections appeared most regardless of age. And in the permanent motive, also, to have a change appeared most regardless of age. And people had a preference natural to role up to setting regardless of age in permanent wave. In hair color section, women whose age is 20's, 30's, 40's had a motive for a change, on the other hand, 50's and their senior had a motive for a gray hair. Women of all over the age almost knew a fashion color, and they had a preference brown color. In a preference way along a hair color kind, there was a significant difference according to age, also. 20's and 30's did mainly 'semi-permanent coating' and 40's and 50's did mainly 'permanent hair color'. In a attitude about a hair-style management, the more age is young, the more a period is long term. And the more age is old, the more the outlay for price of cut is expensive. But, on the contrary, permanent price showed that the more age is young, the more the outlay for price of permanent is expensive. In hair color, the more age is old, the more a period is short and the more price is low.

• Journal of Veterinary Science
• /
• v.22 no.1
• /
• pp.3.1-3.13
• /
• 2021

Background: Multifidus muscle stiffness decreases in patients with lumbar intervertebral disk herniation; however, age-related changes in humans have not been reported. Objectives: The reliability of ultrasound shear wave elastography in dogs, and changes in the shear elastic modulus of the thoracolumbar multifidus muscle with aging in dogs, were investigated. Methods: Twelve beagle dogs were divided into 2 groups based on the age of onset of intervertebral disk herniation: young (aged not exceeding 2 years; 1.3 ± 0.6 years old, n = 5) and adult (4.9 ± 1.2 years old, n = 7). The shear elastic modulus of the multifidus muscle, from the thirteenth thoracic spine to the fourth lumbar spine, was measured using ultrasound shear wave elastography. The length, cross-sectional area and muscle to fat ratio of the multifidus muscle, and the grade of intervertebral disk degeneration, were assessed using radiographic and magnetic resonance imaging examinations. Results: The length and cross-sectional area of the multifidus muscle increased caudally. In the young group, the shear elastic modulus of the multifidus muscle of the thirteenth thoracic spine was less than that of the third lumbar spine. In the adult group, the shear elastic modulus of the multifidus muscle of first and third lumbar spine was lower than that of the same site in the young group. Conclusions: Ultrasound can be used to measure shear wave elastography of the thoracolumbar multifidus in dogs. If the multifidus muscle stiffness decreases, we should consider age-related change.

• Journal of Genetic Medicine
• /
• v.19 no.2
• /
• pp.100-104
• /
• 2022

The gene encoding solute carrier family 9 member 6 (SLC9A6) on Xq26.3 is associated with Christianson syndrome (CS) mimicking Angelman syndrome. In CS, developmental and epileptic encephalopathy (DEE) appears in about 20%, and DEE with spike-and-wave activation in sleep (SWAS) is reported only in several cases. A 10-year-old boy with DEE showed multidrug resistant focal seizures from 6 months of age. He had progressive microcephaly, regression, global developmental delay without speech, hyperkinesia, and truncal ataxia; he had a long thin face, esotropia, and happy demeanor. Brain magnetic resonance imaging demonstrated cerebellar atrophy. Electroencephalogram at 7.5 years of age showed nearly continuous diffuse paroxysms in slow wave sleep. The seizures were responsive to corticosteroids for a while. Trio whole exome sequencing exhibited a likely pathogenic variant of SLC9A6 in the proband and his asymptomatic mother: c.1194dup (p.Leu399AlafsTer12). This is a rare case report of CS with DEE-SWAS in a Korean patient.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.11 no.2
• /
• pp.22-31
• /
• 1991

Various types of ultrasonic techniques have been used for the estimation of compressive strength of concrete structures. However, conventional ultrasonic velocity method using only longitudial wave cannot be determined the compressive strength of concrete structures with accuracy. In this paper, by using the introduction of multiple parameter, e. g. velocity of shear wave, velocity of longitudinal wave, attenuation coefficient of shear wave, attenuation coefficient of longitudinal wave, combination condition, age and preservation method, multiple regression analysis method was applied to the determination of compressive strength of concrete structures. The experimental results show that velocity of shear wave can be estimated compressive strength of concrete with more accuracy compared with the velocity of longitudinal wave, accuracy of estimated error range of compressive strength of concrete structures can be enhanced within the range of ${\pm}$10% approximately.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.9 no.1
• /
• pp.59-68
• /
• 2005

Background and purpose: Cardiovascular disease will undoubtedly rise along with the aging of the 'baby-boom' generation. The purpose of this study is to find the new index of the cardiovascular aging. Methods: The effects of aging on the heart and the arterial system are surveyed in the point of structure and function. Results: Arterial stiffening is due to the fatiguing effects of periodic stress on the arterial wall and is the main reason for increasing pulse wave velocity. The systolic hypertension is caused by the early return of wave reflection. The increased after-load by the arterial change leads to the development of left ventricular hypertrophy. The reduction in left ventricular compliance cause the impairments of the diastolic function. In contrast to the lower limb, aging effect in the upper limb are almost due to the ascending aortic pressure wave and the reflected wave from the lower limb. Conclusion: We have the following points. (1) The change of physiological pulse pattern by age can be explained by the early returning of reflected wave. (2) The atrial pulse in old age are generated by the left ventricular hypertrophy.