• Fire Science and Engineering
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• 제31권1호
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• pp.42-49
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• 2017

The present article reports the tracking characteristics of phenolic resin insulation material due to accelerated degradation. For assessing insulation degradation of the phenolic resin insulation material, experiment samples with equivalent years of 0, 10, 20, 30, and 40 years were produced by conducting accelerated degradation experiments using Arrhenius equation. Subsequently, tracking experiments according to KS C IEC 60112 standard were conducted for the experiment samples that were previously subjected to accelerated degradation. According to the measured results for tracking characteristics of phenolic resin subjected to accelerated degradation, upon dropping of 0.1% ammonium chloride, the risks were shown to increase by 1.38 times for the equivalent life of 10 years; 1.45 times for 20 years; 1.62 times for 30 years; and 1.94 times for 40 years based on the equivalent life of 0 year. Upon dropping of 0.01% ammonium chloride, the risks were shown to increase by 1.39 times for the equivalent life of 10 years; 1.52 times for 20 years; 1.99 times for 30 years; and 5.30 times for 40 years. According to the experimental results, the tracking risk was shown to be higher for longer-duration insulation degradation due to aging. In particular, the risk was observed to be greatly increased in the case of the equivalent life of 40 years. Therefore, it is proposed that the occurrence possibility and the risk of electric fires could be minimized through institutional preparation of recommended replacement period by considering risks such as insulation degradation, etc. due to aging.

• Annals of Clinical Neurophysiology
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• 제5권2호
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• pp.192-196
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• 2003

The Lateral dorsal cutaneous branch of sural nerve (LDCB) is a terminal sensory branch of lower extremities. It can be injured frequently in peripheral nerves. However, the normal data of each component of nerve conduction study (NCS) of were not studied at this time. The Nerve Conduction Study of LDCB adults were assessed for amplitude, area, duration and nerve conduction velocity (NCV) in normal fifty. We also evaluated how age, sex and dexterity affect the various components of NCS. The Mean amplitude of LDCB was $9.45{\pm}1.93{\mu}V$, area was $4.05{\pm}0.55{\mu}V/s$, duration was $1.50{\pm}0.13s$, and NCV was $37.9{\pm}3.09m/s$, respectively. The amplitude of right was $10.1{\mu}V$ in men, $8.65{\mu}V$ in women. The area of right was $3.83{\mu}V/s$ in less than 40 years and $4.24{\mu}V/s$ in older than 40 years. The areas of left was $3.86{\mu}V/s$ in less than 40 years and $4.30{\mu}V/s$ in older than 40 years. The NCV was 39.0 m/s in less than 40 years and 36.7 m/s in older than 40 years. All of above differences were statistically significant. There were no statistically significant differences between right and left NCS. Normal data of LDCB could be applicable in peripheral neuropathy or nerve injury.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1387-1390
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• 2014

Background: The aim of this study was to evaluate trends in incidence of breast cancer in women less than 40 years in Asia. Materials and Methods: Registered cases of female breast cancer age less than 40 years and corresponding person years were ascertained from the CI5plus for 10 registries in Asia for the duration of 1970- 2002. Cases were categorized into three age groups: 16-40, 16-29, and 30-40. The 16-40 age group was adjusted to world age population structure. Joinpoint regression analysis was conducted to determine the annual percent of change (APC) and the average annual percent of change (AAPC) for each age group. Results: A total of 23,661 cases of breast cancer occurred in the 10 registries during the 32 years (1970-2002) of follow-up. The overall age adjusted (16-40 group) breast cancer incidence rate increased from 2.28-4.26 cases per 100,000 population corresponding to an AAPC of 2.6% (95%CI 2.1, 3.0). The trend in incidence for the age group 16-29 increased from 0.45-1.07 corresponding to an AAPC of 2.8% (95%CI 1.9, 3.7). In age group 30 to 40, the incidence ranged from 13.3 in year 1970 to 24.8 in year 2002 corresponding to an AAPC of 2.7% (95% CI 2.3, 3.1). There were two statistically significant changing points in the regression line for the age groups 30-40 and 16-40: one point in the year 1975 with an APC of 6.1 (5.1, 7.1), and the other in 1985 with an APC of 0.4% (0.01, 0.8). Conclusions: Our study proved that: 1) the incidence of breast cancer in young women has increased in Asian population during the study period; 2) the rate of increase was very high during the period of 1980-1990.

• Journal of Menopausal Medicine
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• 제24권3호
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• pp.176-182
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• 2018

Objectives: Menopause is associated with adverse metabolic changes in plasma lipoprotein and inflammation markers. Estrogens have beneficial effects on lipid metabolism and inflammation. Isoflavones (ISO) have structurally similar to estradiol. Our objective was analize the effect of soy-ISO on serum lipid and inflammatory markers (sP-selectin and sCD40L) in postmenopausal women. Methods: A 12-week randomized, double-blind, placebo-controlled intervention with soy-ISO (50 mg, twice daily) was conducted in 35 healthy postmenopausal women (55-72 years old). The women were divided in 2 groups: 20 were allocated to soy-ISO, and 15 to a placebo group. Results: The changes of total cholesterol (TC), triglycerides, low-density lipoproteins-cholesterol (LDL-C), high-density lipoprotein-cholesterol, Apo-A1, sP-selectin and sCD40L in 2 groups before and after 12-week treatment showed no statistical significance. In subgroup analysis, soy-ISO supplementation significantly decreased the levels of TC, LDL-C and sCD40L in women under 65 years old, and with null effects on serum lipid and inflammation markers in women over 65 years old. Conclusions: Soy-ISO did not significantly favorable effects on the lipid profile and inflammatory markers in postmenopausal women. However, in women under 65 years of age, soy-ISO significantly decreased the TC, LDL-C and sCD40L, whereas, no effects on lipid profile and inflammation markers in women over 65 years old were observed.

• Clinical and Experimental Reproductive Medicine
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• 제46권3호
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• pp.119-124
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• 2019

Objective: It is widely accepted that aging decreases women's fertility capacity. The aim of this study was to assess correlations between maternal age and the morphokinetic parameters and cleavage pattern of embryos. Methods: The morphokinetics of embryos derived from women < 30, 30-35, 36-40, and > 40 years of age were compared retrospectively in terms of time of second polar body extrusion, time of pronuclei appearance, time of pronuclei fading, and time of two to eight discrete cells (t2-t8). Furthermore, abnormal cleavage patterns such as uneven blastomeres at the two-cell stage, cell fusion (Fu), and trichotomous mitoses (TM) were assessed. Results: Only t5 occurred later in women aged 36-40 and > 40 years when compared with those aged < 30 and 30-35 years (p< 0.001). Other morphokinetic timing parameters, as well the presence of uneven blastomeres, were comparable between the groups (p> 0.05). However, Fu and TM were more common in women aged > 40 years than in younger women (p< 0.001). Conclusion: Maternal age was correlated with the cleavage pattern of embryos. Therefore, evaluating embryo morphokinetics may contribute to optimal embryo selection, thereby increasing fertility in patients with advanced maternal age.

• Journal of the Korea Convergence Society
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• 제13권2호
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• pp.93-101
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• 2022

Based on the nutritional component analysis data of the Rural Development Administration, the change in the main nutrients of vegetables for 40 years from 1981 to 2021 was investigated. Nutrients that showed a decreasing tendency during the investigation period in fruit vegetables were calcium, iron, thiamine, riboflavin, and ascorbic acid, etc. In root vegetables, it tended to decrease in calcium, thiamine, riboflavin, niacin, and ascorbic acid, etc. In leaf vegetables, it tended to decrease in iron, niacin, and ascorbic acid, etc. In leaf and stem vegetables, it tended to decrease in energy, phosphorus, iron, thiamine, riboflavin, niacin, and ascorbic acid, etc. In particular, it has been confirmed that vitamin reductions such as thiamine, riboflavin, niacin, and ascorbic acid, which have important meanings in vegetable intake, have occurred in vegetables over the past 40 years.

• Korean Journal of Clinical Laboratory Science
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• 제44권1호
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• pp.1-6
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• 2012

Hepatitis A virus (HAV) is an epidemiologically important virus with a worldwide distribution. It causes acute hepatitis in humans. HAV infection is often subclinical or asymptomatic in children; however, symptomatic acute infections become more common with age. In this study, we investigated the prevalence of anti-HAV among hospital workers in Jeonbuk province. 447 (127 males, 320 females) persons were included in the study from January to June, 2011. Anti-HAV (total and IgM) in the sample serum was measured by VIDAS Hepatitis A (bioMerieux, France), and IgM positive samples were tested in terms of their serum alanine aminotransferase (ALT) levels by a HITACHI 7600-010 automatic analyzer (HITACHI, Japan). The overall prevalence of total anti-HAV was 45.9% (205/447), and rate for males (60.6%) was higher than that for females (40%). According to the age group, the prevalence rates of total anti-HAV were 20% (1/5) in those under 20 years old, 11.3% (18/160) in those 20-29 years, 49.7% (71/143) in those 30-39 years, 86.5% (83/96) in those 40-49 years, 92.9% (26/28) in those 50-59 years, and 40% (6/15) in those over 60 years old. The total prevalence of anti-HAV IgM was 0.8% (4/447), and rate for males (1.6%) was higher than that for females (0.6%). Through this study, we determined the prevalence of anti-HAV among hospital workers in Jeonbuk province. The prevalence of the HAV antibody overall was low in hospital workers under 40 years old and in those over 60 years old. Therefore, an improvement in sanitary conditions and hygiene and vaccinations against HAV in this population are recommended.

• Journal of Korean Institute of Industrial Engineers
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• 제40권6호
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• pp.555-567
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• 2014

Over 40 years, the domestic manufacturing industry of Korea played the vital role in creating national wealth, employment and innovation in its economy. In 2011, industrial products made up 99.7 percent of exports, and formed 31.2 percent of GDP. Given those facts, the research of manufacturing systems engineering for higher manufacturing efficiency and its industrial applications have been essential for Korea's economic growth. In this paper, for celebrating the 40th anniversary of the foundation of Korea institute of industrial engineers (KIIE), the research results and its industrial applications of KIIE are reviewed and summarized in the area of manufacturing systems engineering over past 40 years. Directions of future manufacturing system and the role of industrial engineers for our continuous economic growth are also mentioned.

• Journal of dental hygiene science
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• 제9권2호
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• pp.231-239
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• 2009

The study distributed the total 210 questionnaires to women of childbearing age in Seoul, Gyeonggi and North Chungcheng from March 26, 2008 to April 16, 2008 and made them draw up them directly. The study applied 208 copies excepting two copies not suitable to data process to data analysis. The purpose of the study was to investigate/analyze awareness of dental treatment, oral health conditions and oral health management during the period of pregnancy and to serve the analyzed data as basic data of oral health education program development to improve expectant mothers' behaviors of oral health management: 1. According to the survey by age with regard to a question 'Should expectant mothers take dental treatment during the period of pregnancy?', women of 18~29 years old (41.9%) and more than 50 years old (52.0%) answered 'They should not take dental treatment'. Women of 30~39 years old (53.6%) and 40~49 years old (54.7%) answered 'They should take dental treatment'. According to pregnant experience, expectant mothers (63.9%) and women with their parity (46.3%) answered 'They should take dental treatment'. 34.8% women without their parity answered 'They should take dental treatment' and 34.8% women with Out their parity answered 'They should not take dental treatment'(p < 0.05). 2. According to the survey by age with regard to a question 'Do you brush your teeth lifter having morning sickness during the period of pregnancy?', women of 18~29 years old (67.3%), 30~39 years old (47.3%) answered 'Brush my teeth' and women of 40~49 years old (51.0%) and more than 50 years old (52.0%) answered 'Don't brush my teeth'(p < 0.001). According to pregnant experience, expectant mothers (72.2%) and women with their parity (43.0%) answered 'Brush my teeth'(p < 0.05). 3. With regard to a question 'Are oral aid hygiene supplies required?', women of 18~29 years old (47.3%) and 30~39 years old (46.4%) answered 'Required' and women of 40~49 years old (41.5%) and more than 50 years old (48.0%) answered 'do not know'(p < 0.05). 4. According to the survey by age with regard to a question 'What are you anxious about during the period of dental treatment?', women of more than 50 years old (56.0%) answered 'Expenses' and women of 18~29 years old (39.2%), 30~39 years old (44.6%) and 40~49 years old (41.5%) answered 'Pain'(p < 0.05). According to pregnant experience, expectant mothers answered 'Pain (38.9%), abort ion (27.8%) and expenses (22.2%)' and women with their parity, answered 'Pain (45.0%), expenses (22.8%) and abortion (14.8%). Women without their parity answered 'Expenses (52.2%) and pain (13.0%)'(p < 0.05).

• Journal of Chest Surgery
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• 제33권6호
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• pp.507-511
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• 2000

Background: The prognosis for young patients generally considered to be poor. The purpose of this study was to determined whether the clinical characteristics and the survival rate in young lung cancer patients after surgical treatment differs from that in older patients. Material and Method: Of 526 patients, 28(5.3%) were 30 to 40 years old. We studied the clinical characteristics and prognosis of 28 patients aged 40 years or less(Group 1), in whom primary lung cancer was diagnosed and operated between 1990 and 1997, and compared them with those 498 patients aged more than 40 years(Group 2). Result: The differences in sex ratio that were higher for women in Group 1, but there was no significant difference (p=0.297). The percentages for smokers and symptoms in Group 1 were significantly less than in Group 2.(p=0.049, p=0.008). Adenocarcinoma was significantly more common (p=0.018) and squamous cell diagnosed was diagnosed as stage IIIb or stage IV in 9 patients(32.1%), while 12.0% of the patients older than 40 years of age had either stage IIIb or stage IV(p=0.002). The 5-year survival rate was 41.3% in Group 1 ; 37.7% in Group 2, and the median survival time was 24.3 months in Group 1 ; 27.0 months is Group 2. There were no significant difference in survival between two age groups(p=0.808). Conclusion: Younger patients have more adenocarcinoma, however have less squamous cell carcinoma, less symptoms and less smoking history. Although younger patients tended to have more advanced disease and less complete resection rate, the recurrence and the long term survival in these patients did not differ that of older patients.