• Journal of Preventive Medicine and Public Health
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• v.33 no.4
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• pp.402-408
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• 2000

Objectives : To investigate possible seasonal patterns of pre-term birth in Korea. Methods : A total number of 2,669,357 single live births reported to the National Statistical Office from 1995 to 1998 were analyzed. Composite monthly cohorts of ongoing pregnancies were constructed for each month of the year and the probability of pre-term birth was estimated. Results : Increases in the probability of a pre-term birth occurred during winter for the birth of first child and during summer for the birth of second or later child. This seasonal variation was similar among groups divided by sex, residency, age of mother, and education of mother. Conclusions : These findings suggests that some environmental factors related to season may partially explain the incidence of premature births.

• The korean journal of orthodontics
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• v.26 no.2 s.55
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• pp.125-139
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• 1996

The author obtained some useful information for the class III treatment from long term observation on the growing patients with class III malocclusion. 8 patients were selected for this study and presentation. From these observation so far my conclusions might be as follows: First in the early correction of the anterior crossbite, considerable forward growth changes were observed in the maxilla Second, as for the growth modification of jaws by orthopedic treatment only limited effects were recognized from the long-term observation Thrid, at early age of patients with anterior crossbite, any data couldn't make me predict the stability after treatment on the long-term basis. Fortunately, however, genial angle showed a marginal possibility of it prediction. Fourth, at an advanced age/ retraction orthopedic force on the mandible and the rapid change in the mandibular position may cause some trouble in the T.M.joint. Finally, the followings are recommendable. As for the anterior crossbite, correct it early as possible, and use orthopedic force under the age of ten. Do not enter the phase II treatment directly. Just wait and observe until the growth were almost completed, focusiong on some important factors such as airway problem, tongue position, and third molar development. Of course, these factors may have some effects on the mandibular growth. for the female, at the age of around 14 years old and the male, around 17 years old, make a final decision whether the patients will continue to be treated orthodontically or surgically Thereby, (I think) the relapse and retreatment problem after treatemnt we have observed so far might be minimized. Furthermore, the active treatment time may be also reduced.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.285-288
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• 1999

Creep is a major parameter to represent long-term behavior of concrete structures concerning serviceability and durability. The effect of creep is recently taking account into crack resistance analysis of early-age concrete concerning durability evaluation. Since existing creep prediction models were proposed to predict creep for hardened concrete, most of them cannot consider effectively the information on microstructure formation and hydration developed in the early-age concrete. In this study, creep tests for early-age concrete made of the type I cement and the type V cement are carried out respectively and creep prediction models are evaluated for the prediction of creep behavior in early-age concrete. A creep prediction model is modified for the prediction of creep in early-age concrete and also verified by comparing prediction results with results of creep tests on early-age concrete.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.647-652
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• 2015

Background: Lung cancer was one of the most common cancers in both men and women all over the world. In this study, we aimed to clarify who could survive after long term chemotherapy in patients with advanced non-small cell lung cancer (NSCLC). Methods: We enrolled 186 patients with stage IV NSCLC after long term chemotherapy from Jun 2006 to Nov 2014 diagnosed in Jiangsu Cancer Hospital. Multiple variables like age, gender, smoking, histology of adenocarcinoma and squamous-cell cancer, number of metastatic sites, metastatic sites (e.g. lung, brain, bone, liver and pleura), hemoglobin, lymphocyte rate (LYR), Change of LYR during multiple therapies, hypertension, diabetes, chronic bronchitis, treatments (e.g.radiotherapy and targeted therapy) were selected. For consideration of factors influencing survival and response for patients with advanced NSCLC, logistic regression analysis and Cox regression analysis were used in an attempt to develop a screening module for patients with elevated survival after long term chemotherapy become possible. Results: Of the total of 186 patients enrolled, 69 survived less than 1 year (short-term group), 45 one to two years, and 72 longer than 3 years (long-term group). For logistic regression analysis, the short-term group was taken as control group and the long-term group as the case group. We found that age, histology of adenocarcinoma, metastatic site (e.g. lung and liver), treatments (e.g. targeted therapy and radiotherapy), LYR, a decreasing tendency of LYR and chronic bronchitis were individually associated with overall survival by Cox regression analysis. A multivariable Cox regression model showed that metastatic site (e.g. lung and liver), histology of adenocarcinoma, treatments (e.g. targeted therapy and radiotherapy) and chronic bronchitis were associated with overall survival. Thus metastatic site (e.g. lung and liver) and chronic bronchitis may be important risk factors for patients with advanced NSCLC. Gender, metastatic site (e.g. lung and liver), LYR and the decreasing tendency of LYR were significantly associated with long-term survival in the individual-variable logistic regression model (P<0.05). On multivariate logistic regression analysis, gender, metastatic site (e.g. lung and liver) and the decreasing tendency of LYR associated with long-term survival. Conclusions: In conclusion, female patients with stage IV adenocarcinoma of NSCLC who had decreasing tendency of LYR during the course therapy and had accepted multiple therapies e.g. more than third-line chemotherapy, radiotherapy and/or targeted therapy might be expected to live longer.

• Journal of the Korean Society of School Health
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• v.12 no.1
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• pp.131-141
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• 1999

The purpose of this study was to serve as a basis for the planning of oral health education and the development of an oral health-promotion program for patients who visited dental clinics by examining how much dental hygienists offered oral health education to adult patients at dental clinics. A parent group was selected, being made up of 1,600 dental hygienists who registered with the Dental Hygienist Association and worked in Seoul. The questionnaire survey was carried out and an ${\chi}^2-test$ was made using the data collected from 218 subjects to determine how their practice of oral health education was different according to certain general characteristics(the sort of organization for which they worked, age, the term of their service, and the mean number of patients per day). As a result, the following findings were obtained: 1. Thees general characteristics made the following differences to the content of oral health, education: The sort of organization for which the subjects worked made a significant difference in the following tooth brushing instruction (p<0.05), the effect of oral prophylaxis or education about aftereffects (p<0.05), the regular examination of prosthesis (p<0.05), smoking-prohibition education (p<0.05), and the prevention poor-quality fillings (p<0.01). The mean number of patients per day made significant differences to the regular examination of prosthesis (p<0.05) and the prevention poor-quality fillings (p<0.01). But no significant disparity was generated by age or the term of service. 2. The general characteristics made the following differences to education about nutrition and diet counseling: The sort of organization for which the subjects worked had a significant effect just on the importance of a balanced menu (p<0.05). Age made significant differences in advice for vitamin, mineral, protein or other nutrients (p<0.01), and the importance of balanced menu (p<0.001). The term of service made significant differences in the importance of balanced menu (p<0.01), and advice for nutrients including vitamin, mineral or protein (p<0.01). 3. The general characteristics made the following differences to the recommendation and use of oral hygiene aids: The sort of oragnization for which they worked made significant differences only to a gingival massager and water pick (p<0.05). No significant difference was produced by age, the term of service or the mean number of patients per day. 4. The use of educational media for oral health was different according to the general characteristics: The use of pamphlets or booklets significantly varied depending on the organization for which they worked and with the mean number of patients per day (p<0.05). The use of slides or slide projectors was significantly affected by age (p<0.05). But no significant disparity was yielded by the term of service. 5. The general characteristics made the following difference as to whether a continued oral management system was carried out or not: The sort of organization for which they worked had very a significant effect on this result (p<0.001), and no significant disparity was made by age, the term of service or the mean number of patients per day. 6. The place where oral health education was giver differed according to the following general characteristics: The sort of organization for which they worked made very a significant difference as to the use of an examination room's dental unit chair or waiting room (p<0.01), and to the use of an oral health education room or reception counter (p<0.001). The term of service had a significant effect on the use of a counseling room (p<0.01). And the mean number of patients per day made significant differences in the use of a dental unit chair or reception counter (p<0.05), and to the use of an oral health education room or waiting room (p<0.01).

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.16 no.2
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• pp.80-88
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• 2013

Purpose: To identify the predictive factors of long-term therapeutic response or resistance to lamivudine treatment in children and adolescents with chronic hepatitis B. Methods: Eighty one children and adolescents with chronic hepatitis B were included, who received lamivudine treatment for at least 6 months. Their condition was monitored for at least 12 months (12-88 months) thereafter. Twenty one (25.9%) were preschool children ($age{\leq}6$). For patients who had developed HBeAg seroconversion or breakthrough, univariate and multivariate analyses were used to identify the effects of age, gender, pretreatment alanine aminotransferase (ALT) and hepatitis B virus DNA levels. Results: HBeAg seroconversion occurred in 49 (60.5%) of the 81 patients after the initiation of the lamivudine therapy. In 65 patients whom were monitored for over 24 months, the seroconversion rate was significantly higher in younger patients (p=0.040), especially in those patients of preschool age ($age{\leq}6$, p=0.031). The seroconversion rate was significantly higher in higher pretreatment ALT (p=0.003). The breakthrough occurred in 21 (25.9%) of the 81. The breakthrough rate was lower in younger aged patients ($age{\leq}6$), and with higher pretreatment ALT levels, but no significant difference. Conclusion: Younger age is a good predictor of HBeAg seroconversion in children with long-term lamivudine treatment as well as high pretreatment ALT levels.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.465-466
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• 2010

In this paper, an integrated system is proposed which can evaluate both the early-age properties and durability performance of concrete structures. This integrated system starts with a hydration model which considers both Portland cement hydration and chemical reactions of supplementary cementing materials (SCM). Based on the degree of hydration of cement and mineral admixtures, the amount of reaction products, the early age heat evolution, chemically bound water, porosity, the early age short-term mechanical behaviors, shrinkage and early-age creep are evaluated as a function of curing age and curing conditions. Furthermore, the durability aspect, such as carbonation of blended concrete and chloride attack, are evaluated considering both the material properties and surrounding environments. The prediction results are verified through experimental results.

• Journal of Chest Surgery
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• v.14 no.4
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• pp.369-380
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• 1981

In this department 504 cases of valve replacement were done since 1968 to the end of October 1981. Since October 31, 1978 to the end of October 1981 ,333 Ionescu-Shiley bovine pericardial xenograft bioprosthetic cardiac valves were replaced in 265 patients. There were 149 males and 116 female. Ages ranged from 2 to 63 years with 25 cases under 15 years of age. Among 265 cases of Ionescu valve replacement there were 157 MVR, 36 VAR, 6 TVR, 45 MVR+ AVR, 16 MVR+TVR and 5 MVR+AVR+TVR cases with mortality of 5.7%, 8.3%, 16.7%, 8.9%, 18.8% and 20% for each group respectively. Over all mortality rate in 265 Ionescu valve replacement cases was 7.9% with 21 total deaths. Main causes of operative deaths were due to LCOS in 7, bleeding in 5, arrhythmia in 3, air embolism in 2,and heart block in 2 cases. There were 12 late complications with 6 deaths. Over all long-term survival rate was 89.8%. MVR showed the highest long-term survival rate with 92.4%, and MVR+AVR+TVR the lower with 80% lower with 80%.Average follow-up period was 14 month duration. Twenty five congenital anomaly cases were operated with Ionescu-valve replacement that consisted of 7 VSD+AI, and 5 Ebstein anomaly cases with over all operative mortality of 16% and late mortality of 14.3% among 21 operative survivors. There were 25 Ionescu valve replacement cases in pediatric patients under the age of 15 years, with 4 operative deaths. Fourteen MVR, 7 AVR, and 3 TVR cases were found. Even though long-term follow-up study was short in postoperative period with total of 33~.0 months among 244 operative survivors ranging one to 36 months, the late survivors showed beneficial long-term results two thromboembolic episodes in 244 patients were found. More cases and longer term follow-up study are warranted for valve replacement in pediatric and TVR cases with Ionescu-valves which have advantageous hemodynamic structures compared with other bio-prosthetic heart valves.

• Journal of Labour Economics
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• v.43 no.2
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• pp.75-107
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• 2020

Using the data from 1980 to 2017, I show the long-term trends in the gender wage gap in Korea and analyze factors using decomposition method. It tended to decline until the 1990s, but gradually slowed after the 2000s. Gelbach(2016)'s decomposition method is used as an alternative rather than Blinder-Oaxaca decomposition. The results show that the proportion of explanation of traditional factors, such as age, education, firm size, industry and occupation, are continuously decreasing in explaining the gender wage gap. Expecially, the proportion of explanation of age and that of education have decreased, and that of industry tended to decrease in the 1990s but to increase after the 2000s.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.545-548
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• 2006

This study has been carried out to examine the properties of concrete according to replacement ratio and curing method of fly ash, in order to increase utilization of it. As the result of experiments, the 7 days of early age strength presented around 20MPa, up to 20% of replacement ratio, which is almost the same strength as non-replacement. However, when the replacement ratio was 30%, the strength was decreased to 16MPa, as 20% reduction compared to the non-replacement condition. In 365 days of long term aging, the strength was 5% higher, up to 20% of the replacement ratio, due to the pozzolanic reaction of fly ash. When the replacement ratio was 30%, it presented similar strength development as the non-replacement condition. Steam curing and autoclave curing increased the short age strength, regardless of the replacement ratio of fly ash; however, they don't have an effect on increasing the 365 days of long term strength. Water curing showed high strength development after 28 days, 51.81MPa, which is around 30% higher than air curing, 38.9MPa, steam curing, 38.6MPa, and autoclave curing, 39MPa. Therefore, water curing was examined as one of the very effective curing methods for developing long term strength of concrete.